diff options
Diffstat (limited to 'Documentation')
457 files changed, 14759 insertions, 6130 deletions
diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX index 708dc4c166e4..2754fe83f0d4 100644 --- a/Documentation/00-INDEX +++ b/Documentation/00-INDEX @@ -64,8 +64,6 @@ auxdisplay/ - misc. LCD driver documentation (cfag12864b, ks0108). backlight/ - directory with info on controlling backlights in flat panel displays -bcache.txt - - Block-layer cache on fast SSDs to improve slow (raid) I/O performance. block/ - info on the Block I/O (BIO) layer. blockdev/ @@ -78,18 +76,10 @@ bus-devices/ - directory with info on TI GPMC (General Purpose Memory Controller) bus-virt-phys-mapping.txt - how to access I/O mapped memory from within device drivers. -cachetlb.txt - - describes the cache/TLB flushing interfaces Linux uses. cdrom/ - directory with information on the CD-ROM drivers that Linux has. cgroup-v1/ - cgroups v1 features, including cpusets and memory controller. -cgroup-v2.txt - - cgroups v2 features, including cpusets and memory controller. -circular-buffers.txt - - how to make use of the existing circular buffer infrastructure -clk.txt - - info on the common clock framework cma/ - Continuous Memory Area (CMA) debugfs interface. conf.py diff --git a/Documentation/ABI/stable/sysfs-bus-vmbus b/Documentation/ABI/stable/sysfs-bus-vmbus index 0c9d9dcd2151..3eaffbb2d468 100644 --- a/Documentation/ABI/stable/sysfs-bus-vmbus +++ b/Documentation/ABI/stable/sysfs-bus-vmbus @@ -1,25 +1,25 @@ -What: /sys/bus/vmbus/devices/vmbus_*/id +What: /sys/bus/vmbus/devices/<UUID>/id Date: Jul 2009 KernelVersion: 2.6.31 Contact: K. Y. Srinivasan <kys@microsoft.com> Description: The VMBus child_relid of the device's primary channel Users: tools/hv/lsvmbus -What: /sys/bus/vmbus/devices/vmbus_*/class_id +What: /sys/bus/vmbus/devices/<UUID>/class_id Date: Jul 2009 KernelVersion: 2.6.31 Contact: K. Y. Srinivasan <kys@microsoft.com> Description: The VMBus interface type GUID of the device Users: tools/hv/lsvmbus -What: /sys/bus/vmbus/devices/vmbus_*/device_id +What: /sys/bus/vmbus/devices/<UUID>/device_id Date: Jul 2009 KernelVersion: 2.6.31 Contact: K. Y. Srinivasan <kys@microsoft.com> Description: The VMBus interface instance GUID of the device Users: tools/hv/lsvmbus -What: /sys/bus/vmbus/devices/vmbus_*/channel_vp_mapping +What: /sys/bus/vmbus/devices/<UUID>/channel_vp_mapping Date: Jul 2015 KernelVersion: 4.2.0 Contact: K. Y. Srinivasan <kys@microsoft.com> @@ -28,112 +28,112 @@ Description: The mapping of which primary/sub channels are bound to which Format: <channel's child_relid:the bound cpu's number> Users: tools/hv/lsvmbus -What: /sys/bus/vmbus/devices/vmbus_*/device +What: /sys/bus/vmbus/devices/<UUID>/device Date: Dec. 2015 KernelVersion: 4.5 Contact: K. Y. Srinivasan <kys@microsoft.com> Description: The 16 bit device ID of the device Users: tools/hv/lsvmbus and user level RDMA libraries -What: /sys/bus/vmbus/devices/vmbus_*/vendor +What: /sys/bus/vmbus/devices/<UUID>/vendor Date: Dec. 2015 KernelVersion: 4.5 Contact: K. Y. Srinivasan <kys@microsoft.com> Description: The 16 bit vendor ID of the device Users: tools/hv/lsvmbus and user level RDMA libraries -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN +What: /sys/bus/vmbus/devices/<UUID>/channels/<N> Date: September. 2017 KernelVersion: 4.14 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: Directory for per-channel information NN is the VMBUS relid associtated with the channel. -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/cpu +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/cpu Date: September. 2017 KernelVersion: 4.14 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: VCPU (sub)channel is affinitized to Users: tools/hv/lsvmbus and other debugging tools -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/cpu +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/cpu Date: September. 2017 KernelVersion: 4.14 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: VCPU (sub)channel is affinitized to Users: tools/hv/lsvmbus and other debugging tools -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/in_mask +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/in_mask Date: September. 2017 KernelVersion: 4.14 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: Host to guest channel interrupt mask Users: Debugging tools -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/latency +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/latency Date: September. 2017 KernelVersion: 4.14 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: Channel signaling latency Users: Debugging tools -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/out_mask +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/out_mask Date: September. 2017 KernelVersion: 4.14 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: Guest to host channel interrupt mask Users: Debugging tools -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/pending +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/pending Date: September. 2017 KernelVersion: 4.14 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: Channel interrupt pending state Users: Debugging tools -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/read_avail +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/read_avail Date: September. 2017 KernelVersion: 4.14 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: Bytes available to read Users: Debugging tools -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/write_avail +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/write_avail Date: September. 2017 KernelVersion: 4.14 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: Bytes available to write Users: Debugging tools -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/events +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/events Date: September. 2017 KernelVersion: 4.14 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: Number of times we have signaled the host Users: Debugging tools -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/interrupts +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/interrupts Date: September. 2017 KernelVersion: 4.14 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: Number of times we have taken an interrupt (incoming) Users: Debugging tools -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/subchannel_id +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/subchannel_id Date: January. 2018 KernelVersion: 4.16 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: Subchannel ID associated with VMBUS channel Users: Debugging tools and userspace drivers -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/monitor_id +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/monitor_id Date: January. 2018 KernelVersion: 4.16 Contact: Stephen Hemminger <sthemmin@microsoft.com> Description: Monitor bit associated with channel Users: Debugging tools and userspace drivers -What: /sys/bus/vmbus/devices/vmbus_*/channels/NN/ring +What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/ring Date: January. 2018 KernelVersion: 4.16 Contact: Stephen Hemminger <sthemmin@microsoft.com> diff --git a/Documentation/ABI/stable/sysfs-devices-node b/Documentation/ABI/stable/sysfs-devices-node index 5b2d0f08867c..3e90e1f3bf0a 100644 --- a/Documentation/ABI/stable/sysfs-devices-node +++ b/Documentation/ABI/stable/sysfs-devices-node @@ -90,4 +90,4 @@ Date: December 2009 Contact: Lee Schermerhorn <lee.schermerhorn@hp.com> Description: The node's huge page size control/query attributes. - See Documentation/vm/hugetlbpage.txt
\ No newline at end of file + See Documentation/admin-guide/mm/hugetlbpage.rst
\ No newline at end of file diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy index 2028f2d093b2..b8465e00ba5f 100644 --- a/Documentation/ABI/testing/ima_policy +++ b/Documentation/ABI/testing/ima_policy @@ -26,7 +26,7 @@ Description: [obj_user=] [obj_role=] [obj_type=]] option: [[appraise_type=]] [permit_directio] - base: func:= [BPRM_CHECK][MMAP_CHECK][FILE_CHECK][MODULE_CHECK] + base: func:= [BPRM_CHECK][MMAP_CHECK][CREDS_CHECK][FILE_CHECK][MODULE_CHECK] [FIRMWARE_CHECK] [KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK] mask:= [[^]MAY_READ] [[^]MAY_WRITE] [[^]MAY_APPEND] diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb index c702c78f24d8..08d456e07b53 100644 --- a/Documentation/ABI/testing/sysfs-bus-usb +++ b/Documentation/ABI/testing/sysfs-bus-usb @@ -189,6 +189,28 @@ Description: The file will read "hotplug", "wired" and "not used" if the information is available, and "unknown" otherwise. +What: /sys/bus/usb/devices/.../(hub interface)/portX/quirks +Date: May 2018 +Contact: Nicolas Boichat <drinkcat@chromium.org> +Description: + In some cases, we care about time-to-active for devices + connected on a specific port (e.g. non-standard USB port like + pogo pins), where the device to be connected is known in + advance, and behaves well according to the specification. + This attribute is a bit-field that controls the behavior of + a specific port: + - Bit 0 of this field selects the "old" enumeration scheme, + as it is considerably faster (it only causes one USB reset + instead of 2). + The old enumeration scheme can also be selected globally + using /sys/module/usbcore/parameters/old_scheme_first, but + it is often not desirable as the new scheme was introduced to + increase compatibility with more devices. + - Bit 1 reduces TRSTRCY to the 10 ms that are required by the + USB 2.0 specification, instead of the 50 ms that are normally + used to help make enumeration work better on some high speed + devices. + What: /sys/bus/usb/devices/.../(hub interface)/portX/over_current_count Date: February 2018 Contact: Richard Leitner <richard.leitner@skidata.com> @@ -236,3 +258,21 @@ Description: Supported values are 0 - 15. More information on how besl values map to microseconds can be found in USB 2.0 ECN Errata for Link Power Management, section 4.10) + +What: /sys/bus/usb/devices/.../rx_lanes +Date: March 2018 +Contact: Mathias Nyman <mathias.nyman@linux.intel.com> +Description: + Number of rx lanes the device is using. + USB 3.2 adds Dual-lane support, 2 rx and 2 tx lanes over Type-C. + Inter-Chip SSIC devices support asymmetric lanes up to 4 lanes per + direction. Devices before USB 3.2 are single lane (rx_lanes = 1) + +What: /sys/bus/usb/devices/.../tx_lanes +Date: March 2018 +Contact: Mathias Nyman <mathias.nyman@linux.intel.com> +Description: + Number of tx lanes the device is using. + USB 3.2 adds Dual-lane support, 2 rx and 2 tx -lanes over Type-C. + Inter-Chip SSIC devices support asymmetric lanes up to 4 lanes per + direction. Devices before USB 3.2 are single lane (tx_lanes = 1) diff --git a/Documentation/ABI/testing/sysfs-class-cxl b/Documentation/ABI/testing/sysfs-class-cxl index 640f65e79ef1..8e69345c37cc 100644 --- a/Documentation/ABI/testing/sysfs-class-cxl +++ b/Documentation/ABI/testing/sysfs-class-cxl @@ -244,3 +244,11 @@ Description: read only Returns 1 if the psl timebase register is synchronized with the core timebase register, 0 otherwise. Users: https://github.com/ibm-capi/libcxl + +What: /sys/class/cxl/<card>/tunneled_ops_supported +Date: May 2018 +Contact: linuxppc-dev@lists.ozlabs.org +Description: read only + Returns 1 if tunneled operations are supported in capi mode, + 0 otherwise. +Users: https://github.com/ibm-capi/libcxl diff --git a/Documentation/ABI/testing/sysfs-class-power b/Documentation/ABI/testing/sysfs-class-power index f85ce9e327b9..5e23e22dce1b 100644 --- a/Documentation/ABI/testing/sysfs-class-power +++ b/Documentation/ABI/testing/sysfs-class-power @@ -1,3 +1,458 @@ +===== General Properties ===== + +What: /sys/class/power_supply/<supply_name>/manufacturer +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports the name of the device manufacturer. + + Access: Read + Valid values: Represented as string + +What: /sys/class/power_supply/<supply_name>/model_name +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports the name of the device model. + + Access: Read + Valid values: Represented as string + +What: /sys/class/power_supply/<supply_name>/serial_number +Date: January 2008 +Contact: linux-pm@vger.kernel.org +Description: + Reports the serial number of the device. + + Access: Read + Valid values: Represented as string + +What: /sys/class/power_supply/<supply_name>/type +Date: May 2010 +Contact: linux-pm@vger.kernel.org +Description: + Describes the main type of the supply. + + Access: Read + Valid values: "Battery", "UPS", "Mains", "USB" + +===== Battery Properties ===== + +What: /sys/class/power_supply/<supply_name>/capacity +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Fine grain representation of battery capacity. + Access: Read + Valid values: 0 - 100 (percent) + +What: /sys/class/power_supply/<supply_name>/capacity_alert_max +Date: July 2012 +Contact: linux-pm@vger.kernel.org +Description: + Maximum battery capacity trip-wire value where the supply will + notify user-space of the event. This is normally used for the + battery discharging scenario where user-space needs to know the + battery has dropped to an upper level so it can take + appropriate action (e.g. warning user that battery level is + low). + + Access: Read, Write + Valid values: 0 - 100 (percent) + +What: /sys/class/power_supply/<supply_name>/capacity_alert_min +Date: July 2012 +Contact: linux-pm@vger.kernel.org +Description: + Minimum battery capacity trip-wire value where the supply will + notify user-space of the event. This is normally used for the + battery discharging scenario where user-space needs to know the + battery has dropped to a lower level so it can take + appropriate action (e.g. warning user that battery level is + critically low). + + Access: Read, Write + Valid values: 0 - 100 (percent) + +What: /sys/class/power_supply/<supply_name>/capacity_level +Date: June 2009 +Contact: linux-pm@vger.kernel.org +Description: + Coarse representation of battery capacity. + + Access: Read + Valid values: "Unknown", "Critical", "Low", "Normal", "High", + "Full" + +What: /sys/class/power_supply/<supply_name>/current_avg +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports an average IBAT current reading for the battery, over a + fixed period. Normally devices will provide a fixed interval in + which they average readings to smooth out the reported value. + + Access: Read + Valid values: Represented in microamps + +What: /sys/class/power_supply/<supply_name>/current_max +Date: October 2010 +Contact: linux-pm@vger.kernel.org +Description: + Reports the maximum IBAT current allowed into the battery. + + Access: Read + Valid values: Represented in microamps + +What: /sys/class/power_supply/<supply_name>/current_now +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports an instant, single IBAT current reading for the battery. + This value is not averaged/smoothed. + + Access: Read + Valid values: Represented in microamps + +What: /sys/class/power_supply/<supply_name>/charge_type +Date: July 2009 +Contact: linux-pm@vger.kernel.org +Description: + Represents the type of charging currently being applied to the + battery. + + Access: Read + Valid values: "Unknown", "N/A", "Trickle", "Fast" + +What: /sys/class/power_supply/<supply_name>/charge_term_current +Date: July 2014 +Contact: linux-pm@vger.kernel.org +Description: + Reports the charging current value which is used to determine + when the battery is considered full and charging should end. + + Access: Read + Valid values: Represented in microamps + +What: /sys/class/power_supply/<supply_name>/health +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports the health of the battery or battery side of charger + functionality. + + Access: Read + Valid values: "Unknown", "Good", "Overheat", "Dead", + "Over voltage", "Unspecified failure", "Cold", + "Watchdog timer expire", "Safety timer expire" + +What: /sys/class/power_supply/<supply_name>/precharge_current +Date: June 2017 +Contact: linux-pm@vger.kernel.org +Description: + Reports the charging current applied during pre-charging phase + for a battery charge cycle. + + Access: Read + Valid values: Represented in microamps + +What: /sys/class/power_supply/<supply_name>/present +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports whether a battery is present or not in the system. + + Access: Read + Valid values: + 0: Absent + 1: Present + +What: /sys/class/power_supply/<supply_name>/status +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Represents the charging status of the battery. Normally this + is read-only reporting although for some supplies this can be + used to enable/disable charging to the battery. + + Access: Read, Write + Valid values: "Unknown", "Charging", "Discharging", + "Not charging", "Full" + +What: /sys/class/power_supply/<supply_name>/technology +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Describes the battery technology supported by the supply. + + Access: Read + Valid values: "Unknown", "NiMH", "Li-ion", "Li-poly", "LiFe", + "NiCd", "LiMn" + +What: /sys/class/power_supply/<supply_name>/temp +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports the current TBAT battery temperature reading. + + Access: Read + Valid values: Represented in 1/10 Degrees Celsius + +What: /sys/class/power_supply/<supply_name>/temp_alert_max +Date: July 2012 +Contact: linux-pm@vger.kernel.org +Description: + Maximum TBAT temperature trip-wire value where the supply will + notify user-space of the event. This is normally used for the + battery charging scenario where user-space needs to know the + battery temperature has crossed an upper threshold so it can + take appropriate action (e.g. warning user that battery level is + critically high, and charging has stopped). + + Access: Read + Valid values: Represented in 1/10 Degrees Celsius + +What: /sys/class/power_supply/<supply_name>/temp_alert_min +Date: July 2012 +Contact: linux-pm@vger.kernel.org +Description: + Minimum TBAT temperature trip-wire value where the supply will + notify user-space of the event. This is normally used for the + battery charging scenario where user-space needs to know the + battery temperature has crossed a lower threshold so it can take + appropriate action (e.g. warning user that battery level is + high, and charging current has been reduced accordingly to + remedy the situation). + + Access: Read + Valid values: Represented in 1/10 Degrees Celsius + +What: /sys/class/power_supply/<supply_name>/temp_max +Date: July 2014 +Contact: linux-pm@vger.kernel.org +Description: + Reports the maximum allowed TBAT battery temperature for + charging. + + Access: Read + Valid values: Represented in 1/10 Degrees Celsius + +What: /sys/class/power_supply/<supply_name>/temp_min +Date: July 2014 +Contact: linux-pm@vger.kernel.org +Description: + Reports the minimum allowed TBAT battery temperature for + charging. + + Access: Read + Valid values: Represented in 1/10 Degrees Celsius + +What: /sys/class/power_supply/<supply_name>/voltage_avg, +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports an average VBAT voltage reading for the battery, over a + fixed period. Normally devices will provide a fixed interval in + which they average readings to smooth out the reported value. + + Access: Read + Valid values: Represented in microvolts + +What: /sys/class/power_supply/<supply_name>/voltage_max, +Date: January 2008 +Contact: linux-pm@vger.kernel.org +Description: + Reports the maximum safe VBAT voltage permitted for the battery, + during charging. + + Access: Read + Valid values: Represented in microvolts + +What: /sys/class/power_supply/<supply_name>/voltage_min, +Date: January 2008 +Contact: linux-pm@vger.kernel.org +Description: + Reports the minimum safe VBAT voltage permitted for the battery, + during discharging. + + Access: Read + Valid values: Represented in microvolts + +What: /sys/class/power_supply/<supply_name>/voltage_now, +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports an instant, single VBAT voltage reading for the battery. + This value is not averaged/smoothed. + + Access: Read + Valid values: Represented in microvolts + +===== USB Properties ===== + +What: /sys/class/power_supply/<supply_name>/current_avg +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports an average IBUS current reading over a fixed period. + Normally devices will provide a fixed interval in which they + average readings to smooth out the reported value. + + Access: Read + Valid values: Represented in microamps + + +What: /sys/class/power_supply/<supply_name>/current_max +Date: October 2010 +Contact: linux-pm@vger.kernel.org +Description: + Reports the maximum IBUS current the supply can support. + + Access: Read + Valid values: Represented in microamps + +What: /sys/class/power_supply/<supply_name>/current_now +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports the IBUS current supplied now. This value is generally + read-only reporting, unless the 'online' state of the supply + is set to be programmable, in which case this value can be set + within the reported min/max range. + + Access: Read, Write + Valid values: Represented in microamps + +What: /sys/class/power_supply/<supply_name>/input_current_limit +Date: July 2014 +Contact: linux-pm@vger.kernel.org +Description: + Details the incoming IBUS current limit currently set in the + supply. Normally this is configured based on the type of + connection made (e.g. A configured SDP should output a maximum + of 500mA so the input current limit is set to the same value). + + Access: Read, Write + Valid values: Represented in microamps + +What: /sys/class/power_supply/<supply_name>/online, +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Indicates if VBUS is present for the supply. When the supply is + online, and the supply allows it, then it's possible to switch + between online states (e.g. Fixed -> Programmable for a PD_PPS + USB supply so voltage and current can be controlled). + + Access: Read, Write + Valid values: + 0: Offline + 1: Online Fixed - Fixed Voltage Supply + 2: Online Programmable - Programmable Voltage Supply + +What: /sys/class/power_supply/<supply_name>/temp +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports the current supply temperature reading. This would + normally be the internal temperature of the device itself (e.g + TJUNC temperature of an IC) + + Access: Read + Valid values: Represented in 1/10 Degrees Celsius + +What: /sys/class/power_supply/<supply_name>/temp_alert_max +Date: July 2012 +Contact: linux-pm@vger.kernel.org +Description: + Maximum supply temperature trip-wire value where the supply will + notify user-space of the event. This is normally used for the + charging scenario where user-space needs to know the supply + temperature has crossed an upper threshold so it can take + appropriate action (e.g. warning user that the supply + temperature is critically high, and charging has stopped to + remedy the situation). + + Access: Read + Valid values: Represented in 1/10 Degrees Celsius + +What: /sys/class/power_supply/<supply_name>/temp_alert_min +Date: July 2012 +Contact: linux-pm@vger.kernel.org +Description: + Minimum supply temperature trip-wire value where the supply will + notify user-space of the event. This is normally used for the + charging scenario where user-space needs to know the supply + temperature has crossed a lower threshold so it can take + appropriate action (e.g. warning user that the supply + temperature is high, and charging current has been reduced + accordingly to remedy the situation). + + Access: Read + Valid values: Represented in 1/10 Degrees Celsius + +What: /sys/class/power_supply/<supply_name>/temp_max +Date: July 2014 +Contact: linux-pm@vger.kernel.org +Description: + Reports the maximum allowed supply temperature for operation. + + Access: Read + Valid values: Represented in 1/10 Degrees Celsius + +What: /sys/class/power_supply/<supply_name>/temp_min +Date: July 2014 +Contact: linux-pm@vger.kernel.org +Description: + Reports the mainimum allowed supply temperature for operation. + + Access: Read + Valid values: Represented in 1/10 Degrees Celsius + +What: /sys/class/power_supply/<supply_name>/usb_type +Date: March 2018 +Contact: linux-pm@vger.kernel.org +Description: + Reports what type of USB connection is currently active for + the supply, for example it can show if USB-PD capable source + is attached. + + Access: Read-Only + Valid values: "Unknown", "SDP", "DCP", "CDP", "ACA", "C", "PD", + "PD_DRP", "PD_PPS", "BrickID" + +What: /sys/class/power_supply/<supply_name>/voltage_max +Date: January 2008 +Contact: linux-pm@vger.kernel.org +Description: + Reports the maximum VBUS voltage the supply can support. + + Access: Read + Valid values: Represented in microvolts + +What: /sys/class/power_supply/<supply_name>/voltage_min +Date: January 2008 +Contact: linux-pm@vger.kernel.org +Description: + Reports the minimum VBUS voltage the supply can support. + + Access: Read + Valid values: Represented in microvolts + +What: /sys/class/power_supply/<supply_name>/voltage_now +Date: May 2007 +Contact: linux-pm@vger.kernel.org +Description: + Reports the VBUS voltage supplied now. This value is generally + read-only reporting, unless the 'online' state of the supply + is set to be programmable, in which case this value can be set + within the reported min/max range. + + Access: Read, Write + Valid values: Represented in microvolts + +===== Device Specific Properties ===== + What: /sys/class/power/ds2760-battery.*/charge_now Date: May 2010 KernelVersion: 2.6.35 diff --git a/Documentation/ABI/testing/sysfs-class-rtc b/Documentation/ABI/testing/sysfs-class-rtc index cf60412882f0..95984289a4ee 100644 --- a/Documentation/ABI/testing/sysfs-class-rtc +++ b/Documentation/ABI/testing/sysfs-class-rtc @@ -43,6 +43,14 @@ Contact: linux-rtc@vger.kernel.org Description: (RO) The name of the RTC corresponding to this sysfs directory +What: /sys/class/rtc/rtcX/range +Date: January 2018 +KernelVersion: 4.16 +Contact: linux-rtc@vger.kernel.org +Description: + Valid time range for the RTC, as seconds from epoch, formatted + as [min, max] + What: /sys/class/rtc/rtcX/since_epoch Date: March 2006 KernelVersion: 2.6.17 @@ -57,14 +65,6 @@ Contact: linux-rtc@vger.kernel.org Description: (RO) RTC-provided time in 24-hour notation (hh:mm:ss) -What: /sys/class/rtc/rtcX/*/nvmem -Date: February 2016 -KernelVersion: 4.6 -Contact: linux-rtc@vger.kernel.org -Description: - (RW) The non volatile storage exported as a raw file, as - described in Documentation/nvmem/nvmem.txt - What: /sys/class/rtc/rtcX/offset Date: February 2016 KernelVersion: 4.6 diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index 025b7cf3768d..bd4975e132d3 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -478,6 +478,7 @@ What: /sys/devices/system/cpu/vulnerabilities /sys/devices/system/cpu/vulnerabilities/meltdown /sys/devices/system/cpu/vulnerabilities/spectre_v1 /sys/devices/system/cpu/vulnerabilities/spectre_v2 + /sys/devices/system/cpu/vulnerabilities/spec_store_bypass Date: January 2018 Contact: Linux kernel mailing list <linux-kernel@vger.kernel.org> Description: Information about CPU vulnerabilities diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-hugepages b/Documentation/ABI/testing/sysfs-kernel-mm-hugepages index e21c00571cf4..fdaa2162fae1 100644 --- a/Documentation/ABI/testing/sysfs-kernel-mm-hugepages +++ b/Documentation/ABI/testing/sysfs-kernel-mm-hugepages @@ -12,4 +12,4 @@ Description: free_hugepages surplus_hugepages resv_hugepages - See Documentation/vm/hugetlbpage.txt for details. + See Documentation/admin-guide/mm/hugetlbpage.rst for details. diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-ksm b/Documentation/ABI/testing/sysfs-kernel-mm-ksm index 73e653ee2481..dfc13244cda3 100644 --- a/Documentation/ABI/testing/sysfs-kernel-mm-ksm +++ b/Documentation/ABI/testing/sysfs-kernel-mm-ksm @@ -40,7 +40,7 @@ Description: Kernel Samepage Merging daemon sysfs interface sleep_millisecs: how many milliseconds ksm should sleep between scans. - See Documentation/vm/ksm.txt for more information. + See Documentation/vm/ksm.rst for more information. What: /sys/kernel/mm/ksm/merge_across_nodes Date: January 2013 diff --git a/Documentation/ABI/testing/sysfs-kernel-slab b/Documentation/ABI/testing/sysfs-kernel-slab index 2cc0a72b64be..29601d93a1c2 100644 --- a/Documentation/ABI/testing/sysfs-kernel-slab +++ b/Documentation/ABI/testing/sysfs-kernel-slab @@ -37,7 +37,7 @@ Description: The alloc_calls file is read-only and lists the kernel code locations from which allocations for this cache were performed. The alloc_calls file only contains information if debugging is - enabled for that cache (see Documentation/vm/slub.txt). + enabled for that cache (see Documentation/vm/slub.rst). What: /sys/kernel/slab/cache/alloc_fastpath Date: February 2008 @@ -219,7 +219,7 @@ Contact: Pekka Enberg <penberg@cs.helsinki.fi>, Description: The free_calls file is read-only and lists the locations of object frees if slab debugging is enabled (see - Documentation/vm/slub.txt). + Documentation/vm/slub.rst). What: /sys/kernel/slab/cache/free_fastpath Date: February 2008 diff --git a/Documentation/RCU/whatisRCU.txt b/Documentation/RCU/whatisRCU.txt index a27fbfb0efb8..65eb856526b7 100644 --- a/Documentation/RCU/whatisRCU.txt +++ b/Documentation/RCU/whatisRCU.txt @@ -1,3 +1,5 @@ +What is RCU? -- "Read, Copy, Update" + Please note that the "What is RCU?" LWN series is an excellent place to start learning about RCU: diff --git a/Documentation/acpi/cppc_sysfs.txt b/Documentation/acpi/cppc_sysfs.txt new file mode 100644 index 000000000000..f20fb445135d --- /dev/null +++ b/Documentation/acpi/cppc_sysfs.txt @@ -0,0 +1,69 @@ + + Collaborative Processor Performance Control (CPPC) + +CPPC defined in the ACPI spec describes a mechanism for the OS to manage the +performance of a logical processor on a contigious and abstract performance +scale. CPPC exposes a set of registers to describe abstract performance scale, +to request performance levels and to measure per-cpu delivered performance. + +For more details on CPPC please refer to the ACPI specification at: + +http://uefi.org/specifications + +Some of the CPPC registers are exposed via sysfs under: + +/sys/devices/system/cpu/cpuX/acpi_cppc/ + +for each cpu X + +-------------------------------------------------------------------------------- + +$ ls -lR /sys/devices/system/cpu/cpu0/acpi_cppc/ +/sys/devices/system/cpu/cpu0/acpi_cppc/: +total 0 +-r--r--r-- 1 root root 65536 Mar 5 19:38 feedback_ctrs +-r--r--r-- 1 root root 65536 Mar 5 19:38 highest_perf +-r--r--r-- 1 root root 65536 Mar 5 19:38 lowest_freq +-r--r--r-- 1 root root 65536 Mar 5 19:38 lowest_nonlinear_perf +-r--r--r-- 1 root root 65536 Mar 5 19:38 lowest_perf +-r--r--r-- 1 root root 65536 Mar 5 19:38 nominal_freq +-r--r--r-- 1 root root 65536 Mar 5 19:38 nominal_perf +-r--r--r-- 1 root root 65536 Mar 5 19:38 reference_perf +-r--r--r-- 1 root root 65536 Mar 5 19:38 wraparound_time + +-------------------------------------------------------------------------------- + +* highest_perf : Highest performance of this processor (abstract scale). +* nominal_perf : Highest sustained performance of this processor (abstract scale). +* lowest_nonlinear_perf : Lowest performance of this processor with nonlinear + power savings (abstract scale). +* lowest_perf : Lowest performance of this processor (abstract scale). + +* lowest_freq : CPU frequency corresponding to lowest_perf (in MHz). +* nominal_freq : CPU frequency corresponding to nominal_perf (in MHz). + The above frequencies should only be used to report processor performance in + freqency instead of abstract scale. These values should not be used for any + functional decisions. + +* feedback_ctrs : Includes both Reference and delivered performance counter. + Reference counter ticks up proportional to processor's reference performance. + Delivered counter ticks up proportional to processor's delivered performance. +* wraparound_time: Minimum time for the feedback counters to wraparound (seconds). +* reference_perf : Performance level at which reference performance counter + accumulates (abstract scale). + +-------------------------------------------------------------------------------- + + Computing Average Delivered Performance + +Below describes the steps to compute the average performance delivered by taking +two different snapshots of feedback counters at time T1 and T2. + +T1: Read feedback_ctrs as fbc_t1 + Wait or run some workload +T2: Read feedback_ctrs as fbc_t2 + +delivered_counter_delta = fbc_t2[del] - fbc_t1[del] +reference_counter_delta = fbc_t2[ref] - fbc_t1[ref] + +delivered_perf = (refernce_perf x delivered_counter_delta) / reference_counter_delta diff --git a/Documentation/bcache.txt b/Documentation/admin-guide/bcache.rst index c0ce64d75bbf..c0ce64d75bbf 100644 --- a/Documentation/bcache.txt +++ b/Documentation/admin-guide/bcache.rst diff --git a/Documentation/cgroup-v2.txt b/Documentation/admin-guide/cgroup-v2.rst index 74cdeaed9f7a..74cdeaed9f7a 100644 --- a/Documentation/cgroup-v2.txt +++ b/Documentation/admin-guide/cgroup-v2.rst diff --git a/Documentation/admin-guide/index.rst b/Documentation/admin-guide/index.rst index 5bb9161dbe6a..48d70af11652 100644 --- a/Documentation/admin-guide/index.rst +++ b/Documentation/admin-guide/index.rst @@ -48,6 +48,7 @@ configure specific aspects of kernel behavior to your liking. :maxdepth: 1 initrd + cgroup-v2 serial-console braille-console parport @@ -60,9 +61,11 @@ configure specific aspects of kernel behavior to your liking. mono java ras + bcache pm/index thunderbolt LSM/index + mm/index .. only:: subproject and html diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 34dac7cef4cf..1beb30d8d7fc 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -106,11 +106,11 @@ use by PCI Format: <irq>,<irq>... - acpi_mask_gpe= [HW,ACPI] + acpi_mask_gpe= [HW,ACPI] Due to the existence of _Lxx/_Exx, some GPEs triggered by unsupported hardware/firmware features can result in - GPE floodings that cannot be automatically disabled by - the GPE dispatcher. + GPE floodings that cannot be automatically disabled by + the GPE dispatcher. This facility can be used to prevent such uncontrolled GPE floodings. Format: <int> @@ -389,15 +389,15 @@ Use software keyboard repeat audit= [KNL] Enable the audit sub-system - Format: { "0" | "1" } (0 = disabled, 1 = enabled) - 0 - kernel audit is disabled and can not be enabled - until the next reboot + Format: { "0" | "1" | "off" | "on" } + 0 | off - kernel audit is disabled and can not be + enabled until the next reboot unset - kernel audit is initialized but disabled and will be fully enabled by the userspace auditd. - 1 - kernel audit is initialized and partially enabled, - storing at most audit_backlog_limit messages in - RAM until it is fully enabled by the userspace - auditd. + 1 | on - kernel audit is initialized and partially + enabled, storing at most audit_backlog_limit + messages in RAM until it is fully enabled by the + userspace auditd. Default: unset audit_backlog_limit= [KNL] Set the audit queue size limit. @@ -472,10 +472,10 @@ for platform specific values (SB1, Loongson3 and others). - ccw_timeout_log [S390] + ccw_timeout_log [S390] See Documentation/s390/CommonIO for details. - cgroup_disable= [KNL] Disable a particular controller + cgroup_disable= [KNL] Disable a particular controller Format: {name of the controller(s) to disable} The effects of cgroup_disable=foo are: - foo isn't auto-mounted if you mount all cgroups in @@ -518,7 +518,7 @@ those clocks in any way. This parameter is useful for debug and development, but should not be needed on a platform with proper driver support. For more - information, see Documentation/clk.txt. + information, see Documentation/driver-api/clk.rst. clock= [BUGS=X86-32, HW] gettimeofday clocksource override. [Deprecated] @@ -587,11 +587,6 @@ Sets the size of memory pool for coherent, atomic dma allocations, by default set to 256K. - code_bytes [X86] How many bytes of object code to print - in an oops report. - Range: 0 - 8192 - Default: 64 - com20020= [HW,NET] ARCnet - COM20020 chipset Format: <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]] @@ -641,8 +636,8 @@ hvc<n> Use the hypervisor console device <n>. This is for both Xen and PowerPC hypervisors. - If the device connected to the port is not a TTY but a braille - device, prepend "brl," before the device type, for instance + If the device connected to the port is not a TTY but a braille + device, prepend "brl," before the device type, for instance console=brl,ttyS0 For now, only VisioBraille is supported. @@ -662,7 +657,7 @@ consoleblank= [KNL] The console blank (screen saver) timeout in seconds. A value of 0 disables the blank timer. - Defaults to 0. + Defaults to 0. coredump_filter= [KNL] Change the default value for @@ -730,7 +725,7 @@ or memory reserved is below 4G. cryptomgr.notests - [KNL] Disable crypto self-tests + [KNL] Disable crypto self-tests cs89x0_dma= [HW,NET] Format: <dma> @@ -746,7 +741,7 @@ Format: <port#>,<type> See also Documentation/input/devices/joystick-parport.rst - ddebug_query= [KNL,DYNAMIC_DEBUG] Enable debug messages at early boot + ddebug_query= [KNL,DYNAMIC_DEBUG] Enable debug messages at early boot time. See Documentation/admin-guide/dynamic-debug-howto.rst for details. Deprecated, see dyndbg. @@ -833,7 +828,7 @@ causing system reset or hang due to sending INIT from AP to BSP. - disable_ddw [PPC/PSERIES] + disable_ddw [PPC/PSERIES] Disable Dynamic DMA Window support. Use this if to workaround buggy firmware. @@ -1025,6 +1020,12 @@ address. The serial port must already be setup and configured. Options are not yet supported. + qcom_geni,<addr> + Start an early, polled-mode console on a Qualcomm + Generic Interface (GENI) based serial port at the + specified address. The serial port must already be + setup and configured. Options are not yet supported. + earlyprintk= [X86,SH,ARM,M68k,S390] earlyprintk=vga earlyprintk=efi @@ -1188,7 +1189,7 @@ parameter will force ia64_sal_cache_flush to call ia64_pal_cache_flush instead of SAL_CACHE_FLUSH. - forcepae [X86-32] + forcepae [X86-32] Forcefully enable Physical Address Extension (PAE). Many Pentium M systems disable PAE but may have a functionally usable PAE implementation. @@ -1247,7 +1248,7 @@ gamma= [HW,DRM] - gart_fix_e820= [X86_64] disable the fix e820 for K8 GART + gart_fix_e820= [X86_64] disable the fix e820 for K8 GART Format: off | on default: on @@ -1341,23 +1342,32 @@ x86-64 are 2M (when the CPU supports "pse") and 1G (when the CPU supports the "pdpe1gb" cpuinfo flag). - hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC) - terminal devices. Valid values: 0..8 - hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs. - If specified, z/VM IUCV HVC accepts connections - from listed z/VM user IDs only. + hung_task_panic= + [KNL] Should the hung task detector generate panics. + Format: <integer> + A nonzero value instructs the kernel to panic when a + hung task is detected. The default value is controlled + by the CONFIG_BOOTPARAM_HUNG_TASK_PANIC build-time + option. The value selected by this boot parameter can + be changed later by the kernel.hung_task_panic sysctl. + + hvc_iucv= [S390] Number of z/VM IUCV hypervisor console (HVC) + terminal devices. Valid values: 0..8 + hvc_iucv_allow= [S390] Comma-separated list of z/VM user IDs. + If specified, z/VM IUCV HVC accepts connections + from listed z/VM user IDs only. keep_bootcon [KNL] Do not unregister boot console at start. This is only useful for debugging when something happens in the window between unregistering the boot console and initializing the real console. - i2c_bus= [HW] Override the default board specific I2C bus speed - or register an additional I2C bus that is not - registered from board initialization code. - Format: - <bus_id>,<clkrate> + i2c_bus= [HW] Override the default board specific I2C bus speed + or register an additional I2C bus that is not + registered from board initialization code. + Format: + <bus_id>,<clkrate> i8042.debug [HW] Toggle i8042 debug mode i8042.unmask_kbd_data @@ -1386,7 +1396,7 @@ Default: only on s2r transitions on x86; most other architectures force reset to be always executed i8042.unlock [HW] Unlock (ignore) the keylock - i8042.kbdreset [HW] Reset device connected to KBD port + i8042.kbdreset [HW] Reset device connected to KBD port i810= [HW,DRM] @@ -1521,7 +1531,8 @@ ima_policy= [IMA] The builtin policies to load during IMA setup. - Format: "tcb | appraise_tcb | secure_boot" + Format: "tcb | appraise_tcb | secure_boot | + fail_securely" The "tcb" policy measures all programs exec'd, files mmap'd for exec, and all files opened with the read @@ -1536,19 +1547,24 @@ of files (eg. kexec kernel image, kernel modules, firmware, policy, etc) based on file signatures. + The "fail_securely" policy forces file signature + verification failure also on privileged mounted + filesystems with the SB_I_UNVERIFIABLE_SIGNATURE + flag. + ima_tcb [IMA] Deprecated. Use ima_policy= instead. Load a policy which meets the needs of the Trusted Computing Base. This means IMA will measure all programs exec'd, files mmap'd for exec, and all files opened for read by uid=0. - ima_template= [IMA] + ima_template= [IMA] Select one of defined IMA measurements template formats. Formats: { "ima" | "ima-ng" | "ima-sig" } Default: "ima-ng" ima_template_fmt= - [IMA] Define a custom template format. + [IMA] Define a custom template format. Format: { "field1|...|fieldN" } ima.ahash_minsize= [IMA] Minimum file size for asynchronous hash usage @@ -1591,7 +1607,7 @@ inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver Format: <irq> - int_pln_enable [x86] Enable power limit notification interrupt + int_pln_enable [x86] Enable power limit notification interrupt integrity_audit=[IMA] Format: { "0" | "1" } @@ -1644,39 +1660,39 @@ 0 disables intel_idle and fall back on acpi_idle. 1 to 9 specify maximum depth of C-state. - intel_pstate= [X86] - disable - Do not enable intel_pstate as the default - scaling driver for the supported processors - passive - Use intel_pstate as a scaling driver, but configure it - to work with generic cpufreq governors (instead of - enabling its internal governor). This mode cannot be - used along with the hardware-managed P-states (HWP) - feature. - force - Enable intel_pstate on systems that prohibit it by default - in favor of acpi-cpufreq. Forcing the intel_pstate driver - instead of acpi-cpufreq may disable platform features, such - as thermal controls and power capping, that rely on ACPI - P-States information being indicated to OSPM and therefore - should be used with caution. This option does not work with - processors that aren't supported by the intel_pstate driver - or on platforms that use pcc-cpufreq instead of acpi-cpufreq. - no_hwp - Do not enable hardware P state control (HWP) - if available. - hwp_only - Only load intel_pstate on systems which support - hardware P state control (HWP) if available. - support_acpi_ppc - Enforce ACPI _PPC performance limits. If the Fixed ACPI - Description Table, specifies preferred power management - profile as "Enterprise Server" or "Performance Server", - then this feature is turned on by default. - per_cpu_perf_limits - Allow per-logical-CPU P-State performance control limits using - cpufreq sysfs interface + intel_pstate= [X86] + disable + Do not enable intel_pstate as the default + scaling driver for the supported processors + passive + Use intel_pstate as a scaling driver, but configure it + to work with generic cpufreq governors (instead of + enabling its internal governor). This mode cannot be + used along with the hardware-managed P-states (HWP) + feature. + force + Enable intel_pstate on systems that prohibit it by default + in favor of acpi-cpufreq. Forcing the intel_pstate driver + instead of acpi-cpufreq may disable platform features, such + as thermal controls and power capping, that rely on ACPI + P-States information being indicated to OSPM and therefore + should be used with caution. This option does not work with + processors that aren't supported by the intel_pstate driver + or on platforms that use pcc-cpufreq instead of acpi-cpufreq. + no_hwp + Do not enable hardware P state control (HWP) + if available. + hwp_only + Only load intel_pstate on systems which support + hardware P state control (HWP) if available. + support_acpi_ppc + Enforce ACPI _PPC performance limits. If the Fixed ACPI + Description Table, specifies preferred power management + profile as "Enterprise Server" or "Performance Server", + then this feature is turned on by default. + per_cpu_perf_limits + Allow per-logical-CPU P-State performance control limits using + cpufreq sysfs interface intremap= [X86-64, Intel-IOMMU] on enable Interrupt Remapping (default) @@ -1699,7 +1715,6 @@ nopanic merge nomerge - forcesac soft pt [x86, IA-64] nobypass [PPC/POWERNV] @@ -1840,30 +1855,29 @@ keepinitrd [HW,ARM] kernelcore= [KNL,X86,IA-64,PPC] - Format: nn[KMGTPE] | "mirror" - This parameter - specifies the amount of memory usable by the kernel - for non-movable allocations. The requested amount is - spread evenly throughout all nodes in the system. The - remaining memory in each node is used for Movable - pages. In the event, a node is too small to have both - kernelcore and Movable pages, kernelcore pages will - take priority and other nodes will have a larger number - of Movable pages. The Movable zone is used for the - allocation of pages that may be reclaimed or moved - by the page migration subsystem. This means that - HugeTLB pages may not be allocated from this zone. - Note that allocations like PTEs-from-HighMem still - use the HighMem zone if it exists, and the Normal + Format: nn[KMGTPE] | nn% | "mirror" + This parameter specifies the amount of memory usable by + the kernel for non-movable allocations. The requested + amount is spread evenly throughout all nodes in the + system as ZONE_NORMAL. The remaining memory is used for + movable memory in its own zone, ZONE_MOVABLE. In the + event, a node is too small to have both ZONE_NORMAL and + ZONE_MOVABLE, kernelcore memory will take priority and + other nodes will have a larger ZONE_MOVABLE. + + ZONE_MOVABLE is used for the allocation of pages that + may be reclaimed or moved by the page migration + subsystem. Note that allocations like PTEs-from-HighMem + still use the HighMem zone if it exists, and the Normal zone if it does not. - Instead of specifying the amount of memory (nn[KMGTPE]), - you can specify "mirror" option. In case "mirror" + It is possible to specify the exact amount of memory in + the form of "nn[KMGTPE]", a percentage of total system + memory in the form of "nn%", or "mirror". If "mirror" option is specified, mirrored (reliable) memory is used for non-movable allocations and remaining memory is used - for Movable pages. nn[KMGTPE] and "mirror" are exclusive, - so you can NOT specify nn[KMGTPE] and "mirror" at the same - time. + for Movable pages. "nn[KMGTPE]", "nn%", and "mirror" + are exclusive, so you cannot specify multiple forms. kgdbdbgp= [KGDB,HW] kgdb over EHCI usb debug port. Format: <Controller#>[,poll interval] @@ -1902,6 +1916,9 @@ kvm.ignore_msrs=[KVM] Ignore guest accesses to unhandled MSRs. Default is 0 (don't ignore, but inject #GP) + kvm.enable_vmware_backdoor=[KVM] Support VMware backdoor PV interface. + Default is false (don't support). + kvm.mmu_audit= [KVM] This is a R/W parameter which allows audit KVM MMU at runtime. Default is 0 (off) @@ -2019,7 +2036,7 @@ * [no]ncqtrim: Turn off queued DSM TRIM. * nohrst, nosrst, norst: suppress hard, soft - and both resets. + and both resets. * rstonce: only attempt one reset during hot-unplug link recovery @@ -2207,7 +2224,7 @@ [KNL,SH] Allow user to override the default size for per-device physically contiguous DMA buffers. - memhp_default_state=online/offline + memhp_default_state=online/offline [KNL] Set the initial state for the memory hotplug onlining policy. If not specified, the default value is set according to the @@ -2377,13 +2394,14 @@ mousedev.yres= [MOUSE] Vertical screen resolution, used for devices reporting absolute coordinates, such as tablets - movablecore=nn[KMG] [KNL,X86,IA-64,PPC] This parameter - is similar to kernelcore except it specifies the - amount of memory used for migratable allocations. - If both kernelcore and movablecore is specified, - then kernelcore will be at *least* the specified - value but may be more. If movablecore on its own - is specified, the administrator must be careful + movablecore= [KNL,X86,IA-64,PPC] + Format: nn[KMGTPE] | nn% + This parameter is the complement to kernelcore=, it + specifies the amount of memory used for migratable + allocations. If both kernelcore and movablecore is + specified, then kernelcore will be at *least* the + specified value but may be more. If movablecore on its + own is specified, the administrator must be careful that the amount of memory usable for all allocations is not too small. @@ -2591,6 +2609,9 @@ emulation library even if a 387 maths coprocessor is present. + no5lvl [X86-64] Disable 5-level paging mode. Forces + kernel to use 4-level paging instead. + no_console_suspend [HW] Never suspend the console Disable suspending of consoles during suspend and @@ -2671,6 +2692,9 @@ allow data leaks with this option, which is equivalent to spectre_v2=off. + nospec_store_bypass_disable + [HW] Disable all mitigations for the Speculative Store Bypass vulnerability + noxsave [BUGS=X86] Disables x86 extended register state save and restore using xsave. The kernel will fallback to enabling legacy floating-point and sse state. @@ -2753,7 +2777,7 @@ [X86,PV_OPS] Disable paravirtualized VMware scheduler clock and use the default one. - no-steal-acc [X86,KVM] Disable paravirtualized steal time accounting. + no-steal-acc [X86,KVM] Disable paravirtualized steal time accounting. steal time is computed, but won't influence scheduler behaviour @@ -2814,7 +2838,7 @@ notsc [BUGS=X86-32] Disable Time Stamp Counter nowatchdog [KNL] Disable both lockup detectors, i.e. - soft-lockup and NMI watchdog (hard-lockup). + soft-lockup and NMI watchdog (hard-lockup). nowb [ARM] @@ -2834,7 +2858,7 @@ If the dependencies are under your control, you can turn on cpu0_hotplug. - nps_mtm_hs_ctr= [KNL,ARC] + nps_mtm_hs_ctr= [KNL,ARC] This parameter sets the maximum duration, in cycles, each HW thread of the CTOP can run without interruptions, before HW switches it. @@ -2975,7 +2999,7 @@ pci=option[,option...] [PCI] various PCI subsystem options: earlydump [X86] dump PCI config space before the kernel - changes anything + changes anything off [X86] don't probe for the PCI bus bios [X86-32] force use of PCI BIOS, don't access the hardware directly. Use this if your machine @@ -3063,7 +3087,7 @@ is enabled by default. If you need to use this, please report a bug. nocrs [X86] Ignore PCI host bridge windows from ACPI. - If you need to use this, please report a bug. + If you need to use this, please report a bug. routeirq Do IRQ routing for all PCI devices. This is normally done in pci_enable_device(), so this option is a temporary workaround @@ -3154,18 +3178,13 @@ force Enable ASPM even on devices that claim not to support it. WARNING: Forcing ASPM on may cause system lockups. - pcie_hp= [PCIE] PCI Express Hotplug driver options: - nomsi Do not use MSI for PCI Express Native Hotplug (this - makes all PCIe ports use INTx for hotplug services). - - pcie_ports= [PCIE] PCIe ports handling: - auto Ask the BIOS whether or not to use native PCIe services - associated with PCIe ports (PME, hot-plug, AER). Use - them only if that is allowed by the BIOS. - native Use native PCIe services associated with PCIe ports - unconditionally. - compat Treat PCIe ports as PCI-to-PCI bridges, disable the PCIe - ports driver. + pcie_ports= [PCIE] PCIe port services handling: + native Use native PCIe services (PME, AER, DPC, PCIe hotplug) + even if the platform doesn't give the OS permission to + use them. This may cause conflicts if the platform + also tries to use these services. + compat Disable native PCIe services (PME, AER, DPC, PCIe + hotplug). pcie_port_pm= [PCIE] PCIe port power management handling: off Disable power management of all PCIe ports @@ -3911,7 +3930,7 @@ cache (risks via metadata attacks are mostly unchanged). Debug options disable merging on their own. - For more information see Documentation/vm/slub.txt. + For more information see Documentation/vm/slub.rst. slab_max_order= [MM, SLAB] Determines the maximum allowed order for slabs. @@ -3925,7 +3944,7 @@ slub_debug can create guard zones around objects and may poison objects when not in use. Also tracks the last alloc / free. For more information see - Documentation/vm/slub.txt. + Documentation/vm/slub.rst. slub_memcg_sysfs= [MM, SLUB] Determines whether to enable sysfs directories for @@ -3939,7 +3958,7 @@ Determines the maximum allowed order for slabs. A high setting may cause OOMs due to memory fragmentation. For more information see - Documentation/vm/slub.txt. + Documentation/vm/slub.rst. slub_min_objects= [MM, SLUB] The minimum number of objects per slab. SLUB will @@ -3948,12 +3967,12 @@ the number of objects indicated. The higher the number of objects the smaller the overhead of tracking slabs and the less frequently locks need to be acquired. - For more information see Documentation/vm/slub.txt. + For more information see Documentation/vm/slub.rst. slub_min_order= [MM, SLUB] Determines the minimum page order for slabs. Must be lower than slub_max_order. - For more information see Documentation/vm/slub.txt. + For more information see Documentation/vm/slub.rst. slub_nomerge [MM, SLUB] Same with slab_nomerge. This is supported for legacy. @@ -4021,6 +4040,48 @@ Not specifying this option is equivalent to spectre_v2=auto. + spec_store_bypass_disable= + [HW] Control Speculative Store Bypass (SSB) Disable mitigation + (Speculative Store Bypass vulnerability) + + Certain CPUs are vulnerable to an exploit against a + a common industry wide performance optimization known + as "Speculative Store Bypass" in which recent stores + to the same memory location may not be observed by + later loads during speculative execution. The idea + is that such stores are unlikely and that they can + be detected prior to instruction retirement at the + end of a particular speculation execution window. + + In vulnerable processors, the speculatively forwarded + store can be used in a cache side channel attack, for + example to read memory to which the attacker does not + directly have access (e.g. inside sandboxed code). + + This parameter controls whether the Speculative Store + Bypass optimization is used. + + on - Unconditionally disable Speculative Store Bypass + off - Unconditionally enable Speculative Store Bypass + auto - Kernel detects whether the CPU model contains an + implementation of Speculative Store Bypass and + picks the most appropriate mitigation. If the + CPU is not vulnerable, "off" is selected. If the + CPU is vulnerable the default mitigation is + architecture and Kconfig dependent. See below. + prctl - Control Speculative Store Bypass per thread + via prctl. Speculative Store Bypass is enabled + for a process by default. The state of the control + is inherited on fork. + seccomp - Same as "prctl" above, but all seccomp threads + will disable SSB unless they explicitly opt out. + + Not specifying this option is equivalent to + spec_store_bypass_disable=auto. + + Default mitigations: + X86: If CONFIG_SECCOMP=y "seccomp", otherwise "prctl" + spia_io_base= [HW,MTD] spia_fio_base= spia_pedr= @@ -4309,7 +4370,8 @@ Format: [always|madvise|never] Can be used to control the default behavior of the system with respect to transparent hugepages. - See Documentation/vm/transhuge.txt for more details. + See Documentation/admin-guide/mm/transhuge.rst + for more details. tsc= Disable clocksource stability checks for TSC. Format: <string> @@ -4387,7 +4449,7 @@ usbcore.initial_descriptor_timeout= [USB] Specifies timeout for the initial 64-byte - USB_REQ_GET_DESCRIPTOR request in milliseconds + USB_REQ_GET_DESCRIPTOR request in milliseconds (default 5000 = 5.0 seconds). usbcore.nousb [USB] Disable the USB subsystem diff --git a/Documentation/admin-guide/mm/concepts.rst b/Documentation/admin-guide/mm/concepts.rst new file mode 100644 index 000000000000..291699c810d4 --- /dev/null +++ b/Documentation/admin-guide/mm/concepts.rst @@ -0,0 +1,222 @@ +.. _mm_concepts: + +================= +Concepts overview +================= + +The memory management in Linux is complex system that evolved over the +years and included more and more functionality to support variety of +systems from MMU-less microcontrollers to supercomputers. The memory +management for systems without MMU is called ``nommu`` and it +definitely deserves a dedicated document, which hopefully will be +eventually written. Yet, although some of the concepts are the same, +here we assume that MMU is available and CPU can translate a virtual +address to a physical address. + +.. contents:: :local: + +Virtual Memory Primer +===================== + +The physical memory in a computer system is a limited resource and +even for systems that support memory hotplug there is a hard limit on +the amount of memory that can be installed. The physical memory is not +necessary contiguous, it might be accessible as a set of distinct +address ranges. Besides, different CPU architectures, and even +different implementations of the same architecture have different view +how these address ranges defined. + +All this makes dealing directly with physical memory quite complex and +to avoid this complexity a concept of virtual memory was developed. + +The virtual memory abstracts the details of physical memory from the +application software, allows to keep only needed information in the +physical memory (demand paging) and provides a mechanism for the +protection and controlled sharing of data between processes. + +With virtual memory, each and every memory access uses a virtual +address. When the CPU decodes the an instruction that reads (or +writes) from (or to) the system memory, it translates the `virtual` +address encoded in that instruction to a `physical` address that the +memory controller can understand. + +The physical system memory is divided into page frames, or pages. The +size of each page is architecture specific. Some architectures allow +selection of the page size from several supported values; this +selection is performed at the kernel build time by setting an +appropriate kernel configuration option. + +Each physical memory page can be mapped as one or more virtual +pages. These mappings are described by page tables that allow +translation from virtual address used by programs to real address in +the physical memory. The page tables organized hierarchically. + +The tables at the lowest level of the hierarchy contain physical +addresses of actual pages used by the software. The tables at higher +levels contain physical addresses of the pages belonging to the lower +levels. The pointer to the top level page table resides in a +register. When the CPU performs the address translation, it uses this +register to access the top level page table. The high bits of the +virtual address are used to index an entry in the top level page +table. That entry is then used to access the next level in the +hierarchy with the next bits of the virtual address as the index to +that level page table. The lowest bits in the virtual address define +the offset inside the actual page. + +Huge Pages +========== + +The address translation requires several memory accesses and memory +accesses are slow relatively to CPU speed. To avoid spending precious +processor cycles on the address translation, CPUs maintain a cache of +such translations called Translation Lookaside Buffer (or +TLB). Usually TLB is pretty scarce resource and applications with +large memory working set will experience performance hit because of +TLB misses. + +Many modern CPU architectures allow mapping of the memory pages +directly by the higher levels in the page table. For instance, on x86, +it is possible to map 2M and even 1G pages using entries in the second +and the third level page tables. In Linux such pages are called +`huge`. Usage of huge pages significantly reduces pressure on TLB, +improves TLB hit-rate and thus improves overall system performance. + +There are two mechanisms in Linux that enable mapping of the physical +memory with the huge pages. The first one is `HugeTLB filesystem`, or +hugetlbfs. It is a pseudo filesystem that uses RAM as its backing +store. For the files created in this filesystem the data resides in +the memory and mapped using huge pages. The hugetlbfs is described at +:ref:`Documentation/admin-guide/mm/hugetlbpage.rst <hugetlbpage>`. + +Another, more recent, mechanism that enables use of the huge pages is +called `Transparent HugePages`, or THP. Unlike the hugetlbfs that +requires users and/or system administrators to configure what parts of +the system memory should and can be mapped by the huge pages, THP +manages such mappings transparently to the user and hence the +name. See +:ref:`Documentation/admin-guide/mm/transhuge.rst <admin_guide_transhuge>` +for more details about THP. + +Zones +===== + +Often hardware poses restrictions on how different physical memory +ranges can be accessed. In some cases, devices cannot perform DMA to +all the addressable memory. In other cases, the size of the physical +memory exceeds the maximal addressable size of virtual memory and +special actions are required to access portions of the memory. Linux +groups memory pages into `zones` according to their possible +usage. For example, ZONE_DMA will contain memory that can be used by +devices for DMA, ZONE_HIGHMEM will contain memory that is not +permanently mapped into kernel's address space and ZONE_NORMAL will +contain normally addressed pages. + +The actual layout of the memory zones is hardware dependent as not all +architectures define all zones, and requirements for DMA are different +for different platforms. + +Nodes +===== + +Many multi-processor machines are NUMA - Non-Uniform Memory Access - +systems. In such systems the memory is arranged into banks that have +different access latency depending on the "distance" from the +processor. Each bank is referred as `node` and for each node Linux +constructs an independent memory management subsystem. A node has it's +own set of zones, lists of free and used pages and various statistics +counters. You can find more details about NUMA in +:ref:`Documentation/vm/numa.rst <numa>` and in +:ref:`Documentation/admin-guide/mm/numa_memory_policy.rst <numa_memory_policy>`. + +Page cache +========== + +The physical memory is volatile and the common case for getting data +into the memory is to read it from files. Whenever a file is read, the +data is put into the `page cache` to avoid expensive disk access on +the subsequent reads. Similarly, when one writes to a file, the data +is placed in the page cache and eventually gets into the backing +storage device. The written pages are marked as `dirty` and when Linux +decides to reuse them for other purposes, it makes sure to synchronize +the file contents on the device with the updated data. + +Anonymous Memory +================ + +The `anonymous memory` or `anonymous mappings` represent memory that +is not backed by a filesystem. Such mappings are implicitly created +for program's stack and heap or by explicit calls to mmap(2) system +call. Usually, the anonymous mappings only define virtual memory areas +that the program is allowed to access. The read accesses will result +in creation of a page table entry that references a special physical +page filled with zeroes. When the program performs a write, regular +physical page will be allocated to hold the written data. The page +will be marked dirty and if the kernel will decide to repurpose it, +the dirty page will be swapped out. + +Reclaim +======= + +Throughout the system lifetime, a physical page can be used for storing +different types of data. It can be kernel internal data structures, +DMA'able buffers for device drivers use, data read from a filesystem, +memory allocated by user space processes etc. + +Depending on the page usage it is treated differently by the Linux +memory management. The pages that can be freed at any time, either +because they cache the data available elsewhere, for instance, on a +hard disk, or because they can be swapped out, again, to the hard +disk, are called `reclaimable`. The most notable categories of the +reclaimable pages are page cache and anonymous memory. + +In most cases, the pages holding internal kernel data and used as DMA +buffers cannot be repurposed, and they remain pinned until freed by +their user. Such pages are called `unreclaimable`. However, in certain +circumstances, even pages occupied with kernel data structures can be +reclaimed. For instance, in-memory caches of filesystem metadata can +be re-read from the storage device and therefore it is possible to +discard them from the main memory when system is under memory +pressure. + +The process of freeing the reclaimable physical memory pages and +repurposing them is called (surprise!) `reclaim`. Linux can reclaim +pages either asynchronously or synchronously, depending on the state +of the system. When system is not loaded, most of the memory is free +and allocation request will be satisfied immediately from the free +pages supply. As the load increases, the amount of the free pages goes +down and when it reaches a certain threshold (high watermark), an +allocation request will awaken the ``kswapd`` daemon. It will +asynchronously scan memory pages and either just free them if the data +they contain is available elsewhere, or evict to the backing storage +device (remember those dirty pages?). As memory usage increases even +more and reaches another threshold - min watermark - an allocation +will trigger the `direct reclaim`. In this case allocation is stalled +until enough memory pages are reclaimed to satisfy the request. + +Compaction +========== + +As the system runs, tasks allocate and free the memory and it becomes +fragmented. Although with virtual memory it is possible to present +scattered physical pages as virtually contiguous range, sometimes it is +necessary to allocate large physically contiguous memory areas. Such +need may arise, for instance, when a device driver requires large +buffer for DMA, or when THP allocates a huge page. Memory `compaction` +addresses the fragmentation issue. This mechanism moves occupied pages +from the lower part of a memory zone to free pages in the upper part +of the zone. When a compaction scan is finished free pages are grouped +together at the beginning of the zone and allocations of large +physically contiguous areas become possible. + +Like reclaim, the compaction may happen asynchronously in ``kcompactd`` +daemon or synchronously as a result of memory allocation request. + +OOM killer +========== + +It may happen, that on a loaded machine memory will be exhausted. When +the kernel detects that the system runs out of memory (OOM) it invokes +`OOM killer`. Its mission is simple: all it has to do is to select a +task to sacrifice for the sake of the overall system health. The +selected task is killed in a hope that after it exits enough memory +will be freed to continue normal operation. diff --git a/Documentation/vm/hugetlbpage.txt b/Documentation/admin-guide/mm/hugetlbpage.rst index faf077d50d42..1cc0bc78d10e 100644 --- a/Documentation/vm/hugetlbpage.txt +++ b/Documentation/admin-guide/mm/hugetlbpage.rst @@ -1,3 +1,11 @@ +.. _hugetlbpage: + +============= +HugeTLB Pages +============= + +Overview +======== The intent of this file is to give a brief summary of hugetlbpage support in the Linux kernel. This support is built on top of multiple page size support @@ -18,53 +26,59 @@ First the Linux kernel needs to be built with the CONFIG_HUGETLBFS automatically when CONFIG_HUGETLBFS is selected) configuration options. -The /proc/meminfo file provides information about the total number of +The ``/proc/meminfo`` file provides information about the total number of persistent hugetlb pages in the kernel's huge page pool. It also displays default huge page size and information about the number of free, reserved and surplus huge pages in the pool of huge pages of default size. The huge page size is needed for generating the proper alignment and size of the arguments to system calls that map huge page regions. -The output of "cat /proc/meminfo" will include lines like: +The output of ``cat /proc/meminfo`` will include lines like:: -..... -HugePages_Total: uuu -HugePages_Free: vvv -HugePages_Rsvd: www -HugePages_Surp: xxx -Hugepagesize: yyy kB -Hugetlb: zzz kB + HugePages_Total: uuu + HugePages_Free: vvv + HugePages_Rsvd: www + HugePages_Surp: xxx + Hugepagesize: yyy kB + Hugetlb: zzz kB where: -HugePages_Total is the size of the pool of huge pages. -HugePages_Free is the number of huge pages in the pool that are not yet - allocated. -HugePages_Rsvd is short for "reserved," and is the number of huge pages for - which a commitment to allocate from the pool has been made, - but no allocation has yet been made. Reserved huge pages - guarantee that an application will be able to allocate a - huge page from the pool of huge pages at fault time. -HugePages_Surp is short for "surplus," and is the number of huge pages in - the pool above the value in /proc/sys/vm/nr_hugepages. The - maximum number of surplus huge pages is controlled by - /proc/sys/vm/nr_overcommit_hugepages. -Hugepagesize is the default hugepage size (in Kb). -Hugetlb is the total amount of memory (in kB), consumed by huge - pages of all sizes. - If huge pages of different sizes are in use, this number - will exceed HugePages_Total * Hugepagesize. To get more - detailed information, please, refer to - /sys/kernel/mm/hugepages (described below). - - -/proc/filesystems should also show a filesystem of type "hugetlbfs" configured -in the kernel. - -/proc/sys/vm/nr_hugepages indicates the current number of "persistent" huge + +HugePages_Total + is the size of the pool of huge pages. +HugePages_Free + is the number of huge pages in the pool that are not yet + allocated. +HugePages_Rsvd + is short for "reserved," and is the number of huge pages for + which a commitment to allocate from the pool has been made, + but no allocation has yet been made. Reserved huge pages + guarantee that an application will be able to allocate a + huge page from the pool of huge pages at fault time. +HugePages_Surp + is short for "surplus," and is the number of huge pages in + the pool above the value in ``/proc/sys/vm/nr_hugepages``. The + maximum number of surplus huge pages is controlled by + ``/proc/sys/vm/nr_overcommit_hugepages``. +Hugepagesize + is the default hugepage size (in Kb). +Hugetlb + is the total amount of memory (in kB), consumed by huge + pages of all sizes. + If huge pages of different sizes are in use, this number + will exceed HugePages_Total \* Hugepagesize. To get more + detailed information, please, refer to + ``/sys/kernel/mm/hugepages`` (described below). + + +``/proc/filesystems`` should also show a filesystem of type "hugetlbfs" +configured in the kernel. + +``/proc/sys/vm/nr_hugepages`` indicates the current number of "persistent" huge pages in the kernel's huge page pool. "Persistent" huge pages will be returned to the huge page pool when freed by a task. A user with root privileges can dynamically allocate more or free some persistent huge pages -by increasing or decreasing the value of 'nr_hugepages'. +by increasing or decreasing the value of ``nr_hugepages``. Pages that are used as huge pages are reserved inside the kernel and cannot be used for other purposes. Huge pages cannot be swapped out under @@ -73,7 +87,7 @@ memory pressure. Once a number of huge pages have been pre-allocated to the kernel huge page pool, a user with appropriate privilege can use either the mmap system call or shared memory system calls to use the huge pages. See the discussion of -Using Huge Pages, below. +:ref:`Using Huge Pages <using_huge_pages>`, below. The administrator can allocate persistent huge pages on the kernel boot command line by specifying the "hugepages=N" parameter, where 'N' = the @@ -86,10 +100,10 @@ with a huge page size selection parameter "hugepagesz=<size>". <size> must be specified in bytes with optional scale suffix [kKmMgG]. The default huge page size may be selected with the "default_hugepagesz=<size>" boot parameter. -When multiple huge page sizes are supported, /proc/sys/vm/nr_hugepages +When multiple huge page sizes are supported, ``/proc/sys/vm/nr_hugepages`` indicates the current number of pre-allocated huge pages of the default size. Thus, one can use the following command to dynamically allocate/deallocate -default sized persistent huge pages: +default sized persistent huge pages:: echo 20 > /proc/sys/vm/nr_hugepages @@ -98,11 +112,12 @@ huge page pool to 20, allocating or freeing huge pages, as required. On a NUMA platform, the kernel will attempt to distribute the huge page pool over all the set of allowed nodes specified by the NUMA memory policy of the -task that modifies nr_hugepages. The default for the allowed nodes--when the +task that modifies ``nr_hugepages``. The default for the allowed nodes--when the task has default memory policy--is all on-line nodes with memory. Allowed nodes with insufficient available, contiguous memory for a huge page will be -silently skipped when allocating persistent huge pages. See the discussion -below of the interaction of task memory policy, cpusets and per node attributes +silently skipped when allocating persistent huge pages. See the +:ref:`discussion below <mem_policy_and_hp_alloc>` +of the interaction of task memory policy, cpusets and per node attributes with the allocation and freeing of persistent huge pages. The success or failure of huge page allocation depends on the amount of @@ -117,51 +132,52 @@ init files. This will enable the kernel to allocate huge pages early in the boot process when the possibility of getting physical contiguous pages is still very high. Administrators can verify the number of huge pages actually allocated by checking the sysctl or meminfo. To check the per node -distribution of huge pages in a NUMA system, use: +distribution of huge pages in a NUMA system, use:: cat /sys/devices/system/node/node*/meminfo | fgrep Huge -/proc/sys/vm/nr_overcommit_hugepages specifies how large the pool of -huge pages can grow, if more huge pages than /proc/sys/vm/nr_hugepages are +``/proc/sys/vm/nr_overcommit_hugepages`` specifies how large the pool of +huge pages can grow, if more huge pages than ``/proc/sys/vm/nr_hugepages`` are requested by applications. Writing any non-zero value into this file indicates that the hugetlb subsystem is allowed to try to obtain that number of "surplus" huge pages from the kernel's normal page pool, when the persistent huge page pool is exhausted. As these surplus huge pages become unused, they are freed back to the kernel's normal page pool. -When increasing the huge page pool size via nr_hugepages, any existing surplus -pages will first be promoted to persistent huge pages. Then, additional +When increasing the huge page pool size via ``nr_hugepages``, any existing +surplus pages will first be promoted to persistent huge pages. Then, additional huge pages will be allocated, if necessary and if possible, to fulfill the new persistent huge page pool size. The administrator may shrink the pool of persistent huge pages for -the default huge page size by setting the nr_hugepages sysctl to a +the default huge page size by setting the ``nr_hugepages`` sysctl to a smaller value. The kernel will attempt to balance the freeing of huge pages -across all nodes in the memory policy of the task modifying nr_hugepages. +across all nodes in the memory policy of the task modifying ``nr_hugepages``. Any free huge pages on the selected nodes will be freed back to the kernel's normal page pool. -Caveat: Shrinking the persistent huge page pool via nr_hugepages such that +Caveat: Shrinking the persistent huge page pool via ``nr_hugepages`` such that it becomes less than the number of huge pages in use will convert the balance of the in-use huge pages to surplus huge pages. This will occur even if -the number of surplus pages it would exceed the overcommit value. As long as -this condition holds--that is, until nr_hugepages+nr_overcommit_hugepages is +the number of surplus pages would exceed the overcommit value. As long as +this condition holds--that is, until ``nr_hugepages+nr_overcommit_hugepages`` is increased sufficiently, or the surplus huge pages go out of use and are freed-- no more surplus huge pages will be allowed to be allocated. With support for multiple huge page pools at run-time available, much of -the huge page userspace interface in /proc/sys/vm has been duplicated in sysfs. -The /proc interfaces discussed above have been retained for backwards -compatibility. The root huge page control directory in sysfs is: +the huge page userspace interface in ``/proc/sys/vm`` has been duplicated in +sysfs. +The ``/proc`` interfaces discussed above have been retained for backwards +compatibility. The root huge page control directory in sysfs is:: /sys/kernel/mm/hugepages For each huge page size supported by the running kernel, a subdirectory -will exist, of the form: +will exist, of the form:: hugepages-${size}kB -Inside each of these directories, the same set of files will exist: +Inside each of these directories, the same set of files will exist:: nr_hugepages nr_hugepages_mempolicy @@ -172,37 +188,39 @@ Inside each of these directories, the same set of files will exist: which function as described above for the default huge page-sized case. +.. _mem_policy_and_hp_alloc: Interaction of Task Memory Policy with Huge Page Allocation/Freeing =================================================================== -Whether huge pages are allocated and freed via the /proc interface or -the /sysfs interface using the nr_hugepages_mempolicy attribute, the NUMA -nodes from which huge pages are allocated or freed are controlled by the -NUMA memory policy of the task that modifies the nr_hugepages_mempolicy -sysctl or attribute. When the nr_hugepages attribute is used, mempolicy +Whether huge pages are allocated and freed via the ``/proc`` interface or +the ``/sysfs`` interface using the ``nr_hugepages_mempolicy`` attribute, the +NUMA nodes from which huge pages are allocated or freed are controlled by the +NUMA memory policy of the task that modifies the ``nr_hugepages_mempolicy`` +sysctl or attribute. When the ``nr_hugepages`` attribute is used, mempolicy is ignored. The recommended method to allocate or free huge pages to/from the kernel -huge page pool, using the nr_hugepages example above, is: +huge page pool, using the ``nr_hugepages`` example above, is:: numactl --interleave <node-list> echo 20 \ >/proc/sys/vm/nr_hugepages_mempolicy -or, more succinctly: +or, more succinctly:: numactl -m <node-list> echo 20 >/proc/sys/vm/nr_hugepages_mempolicy -This will allocate or free abs(20 - nr_hugepages) to or from the nodes +This will allocate or free ``abs(20 - nr_hugepages)`` to or from the nodes specified in <node-list>, depending on whether number of persistent huge pages is initially less than or greater than 20, respectively. No huge pages will be allocated nor freed on any node not included in the specified <node-list>. -When adjusting the persistent hugepage count via nr_hugepages_mempolicy, any +When adjusting the persistent hugepage count via ``nr_hugepages_mempolicy``, any memory policy mode--bind, preferred, local or interleave--may be used. The resulting effect on persistent huge page allocation is as follows: -1) Regardless of mempolicy mode [see Documentation/vm/numa_memory_policy.txt], +#. Regardless of mempolicy mode [see + :ref:`Documentation/admin-guide/mm/numa_memory_policy.rst <numa_memory_policy>`], persistent huge pages will be distributed across the node or nodes specified in the mempolicy as if "interleave" had been specified. However, if a node in the policy does not contain sufficient contiguous @@ -212,7 +230,7 @@ resulting effect on persistent huge page allocation is as follows: possibly, allocation of persistent huge pages on nodes not allowed by the task's memory policy. -2) One or more nodes may be specified with the bind or interleave policy. +#. One or more nodes may be specified with the bind or interleave policy. If more than one node is specified with the preferred policy, only the lowest numeric id will be used. Local policy will select the node where the task is running at the time the nodes_allowed mask is constructed. @@ -222,20 +240,20 @@ resulting effect on persistent huge page allocation is as follows: indeterminate. Thus, local policy is not very useful for this purpose. Any of the other mempolicy modes may be used to specify a single node. -3) The nodes allowed mask will be derived from any non-default task mempolicy, +#. The nodes allowed mask will be derived from any non-default task mempolicy, whether this policy was set explicitly by the task itself or one of its ancestors, such as numactl. This means that if the task is invoked from a shell with non-default policy, that policy will be used. One can specify a node list of "all" with numactl --interleave or --membind [-m] to achieve interleaving over all nodes in the system or cpuset. -4) Any task mempolicy specified--e.g., using numactl--will be constrained by +#. Any task mempolicy specified--e.g., using numactl--will be constrained by the resource limits of any cpuset in which the task runs. Thus, there will be no way for a task with non-default policy running in a cpuset with a subset of the system nodes to allocate huge pages outside the cpuset without first moving to a cpuset that contains all of the desired nodes. -5) Boot-time huge page allocation attempts to distribute the requested number +#. Boot-time huge page allocation attempts to distribute the requested number of huge pages over all on-lines nodes with memory. Per Node Hugepages Attributes @@ -243,22 +261,22 @@ Per Node Hugepages Attributes A subset of the contents of the root huge page control directory in sysfs, described above, will be replicated under each the system device of each -NUMA node with memory in: +NUMA node with memory in:: /sys/devices/system/node/node[0-9]*/hugepages/ Under this directory, the subdirectory for each supported huge page size -contains the following attribute files: +contains the following attribute files:: nr_hugepages free_hugepages surplus_hugepages -The free_' and surplus_' attribute files are read-only. They return the number +The free\_' and surplus\_' attribute files are read-only. They return the number of free and surplus [overcommitted] huge pages, respectively, on the parent node. -The nr_hugepages attribute returns the total number of huge pages on the +The ``nr_hugepages`` attribute returns the total number of huge pages on the specified node. When this attribute is written, the number of persistent huge pages on the parent node will be adjusted to the specified value, if sufficient resources exist, regardless of the task's mempolicy or cpuset constraints. @@ -267,43 +285,58 @@ Note that the number of overcommit and reserve pages remain global quantities, as we don't know until fault time, when the faulting task's mempolicy is applied, from which node the huge page allocation will be attempted. +.. _using_huge_pages: Using Huge Pages ================ If the user applications are going to request huge pages using mmap system call, then it is required that system administrator mount a file system of -type hugetlbfs: +type hugetlbfs:: mount -t hugetlbfs \ -o uid=<value>,gid=<value>,mode=<value>,pagesize=<value>,size=<value>,\ min_size=<value>,nr_inodes=<value> none /mnt/huge This command mounts a (pseudo) filesystem of type hugetlbfs on the directory -/mnt/huge. Any files created on /mnt/huge uses huge pages. The uid and gid -options sets the owner and group of the root of the file system. By default -the uid and gid of the current process are taken. The mode option sets the -mode of root of file system to value & 01777. This value is given in octal. -By default the value 0755 is picked. If the platform supports multiple huge -page sizes, the pagesize option can be used to specify the huge page size and -associated pool. pagesize is specified in bytes. If pagesize is not specified -the platform's default huge page size and associated pool will be used. The -size option sets the maximum value of memory (huge pages) allowed for that -filesystem (/mnt/huge). The size option can be specified in bytes, or as a -percentage of the specified huge page pool (nr_hugepages). The size is -rounded down to HPAGE_SIZE boundary. The min_size option sets the minimum -value of memory (huge pages) allowed for the filesystem. min_size can be -specified in the same way as size, either bytes or a percentage of the -huge page pool. At mount time, the number of huge pages specified by -min_size are reserved for use by the filesystem. If there are not enough -free huge pages available, the mount will fail. As huge pages are allocated -to the filesystem and freed, the reserve count is adjusted so that the sum -of allocated and reserved huge pages is always at least min_size. The option -nr_inodes sets the maximum number of inodes that /mnt/huge can use. If the -size, min_size or nr_inodes option is not provided on command line then -no limits are set. For pagesize, size, min_size and nr_inodes options, you -can use [G|g]/[M|m]/[K|k] to represent giga/mega/kilo. For example, size=2K -has the same meaning as size=2048. +``/mnt/huge``. Any file created on ``/mnt/huge`` uses huge pages. + +The ``uid`` and ``gid`` options sets the owner and group of the root of the +file system. By default the ``uid`` and ``gid`` of the current process +are taken. + +The ``mode`` option sets the mode of root of file system to value & 01777. +This value is given in octal. By default the value 0755 is picked. + +If the platform supports multiple huge page sizes, the ``pagesize`` option can +be used to specify the huge page size and associated pool. ``pagesize`` +is specified in bytes. If ``pagesize`` is not specified the platform's +default huge page size and associated pool will be used. + +The ``size`` option sets the maximum value of memory (huge pages) allowed +for that filesystem (``/mnt/huge``). The ``size`` option can be specified +in bytes, or as a percentage of the specified huge page pool (``nr_hugepages``). +The size is rounded down to HPAGE_SIZE boundary. + +The ``min_size`` option sets the minimum value of memory (huge pages) allowed +for the filesystem. ``min_size`` can be specified in the same way as ``size``, +either bytes or a percentage of the huge page pool. +At mount time, the number of huge pages specified by ``min_size`` are reserved +for use by the filesystem. +If there are not enough free huge pages available, the mount will fail. +As huge pages are allocated to the filesystem and freed, the reserve count +is adjusted so that the sum of allocated and reserved huge pages is always +at least ``min_size``. + +The option ``nr_inodes`` sets the maximum number of inodes that ``/mnt/huge`` +can use. + +If the ``size``, ``min_size`` or ``nr_inodes`` option is not provided on +command line then no limits are set. + +For ``pagesize``, ``size``, ``min_size`` and ``nr_inodes`` options, you can +use [G|g]/[M|m]/[K|k] to represent giga/mega/kilo. +For example, size=2K has the same meaning as size=2048. While read system calls are supported on files that reside on hugetlb file systems, write system calls are not. @@ -313,12 +346,12 @@ used to change the file attributes on hugetlbfs. Also, it is important to note that no such mount command is required if applications are going to use only shmat/shmget system calls or mmap with -MAP_HUGETLB. For an example of how to use mmap with MAP_HUGETLB see map_hugetlb -below. +MAP_HUGETLB. For an example of how to use mmap with MAP_HUGETLB see +:ref:`map_hugetlb <map_hugetlb>` below. -Users who wish to use hugetlb memory via shared memory segment should be a -member of a supplementary group and system admin needs to configure that gid -into /proc/sys/vm/hugetlb_shm_group. It is possible for same or different +Users who wish to use hugetlb memory via shared memory segment should be +members of a supplementary group and system admin needs to configure that gid +into ``/proc/sys/vm/hugetlb_shm_group``. It is possible for same or different applications to use any combination of mmaps and shm* calls, though the mount of filesystem will be required for using mmap calls without MAP_HUGETLB. @@ -332,20 +365,18 @@ a hugetlb page and the length is smaller than the hugepage size. Examples ======== -1) map_hugetlb: see tools/testing/selftests/vm/map_hugetlb.c +.. _map_hugetlb: -2) hugepage-shm: see tools/testing/selftests/vm/hugepage-shm.c +``map_hugetlb`` + see tools/testing/selftests/vm/map_hugetlb.c -3) hugepage-mmap: see tools/testing/selftests/vm/hugepage-mmap.c +``hugepage-shm`` + see tools/testing/selftests/vm/hugepage-shm.c -4) The libhugetlbfs (https://github.com/libhugetlbfs/libhugetlbfs) library - provides a wide range of userspace tools to help with huge page usability, - environment setup, and control. +``hugepage-mmap`` + see tools/testing/selftests/vm/hugepage-mmap.c -Kernel development regression testing -===================================== +The `libhugetlbfs`_ library provides a wide range of userspace tools +to help with huge page usability, environment setup, and control. -The most complete set of hugetlb tests are in the libhugetlbfs repository. -If you modify any hugetlb related code, use the libhugetlbfs test suite -to check for regressions. In addition, if you add any new hugetlb -functionality, please add appropriate tests to libhugetlbfs. +.. _libhugetlbfs: https://github.com/libhugetlbfs/libhugetlbfs diff --git a/Documentation/vm/idle_page_tracking.txt b/Documentation/admin-guide/mm/idle_page_tracking.rst index 85dcc3bb85dc..6f7b7ca1add3 100644 --- a/Documentation/vm/idle_page_tracking.txt +++ b/Documentation/admin-guide/mm/idle_page_tracking.rst @@ -1,4 +1,11 @@ -MOTIVATION +.. _idle_page_tracking: + +================== +Idle Page Tracking +================== + +Motivation +========== The idle page tracking feature allows to track which memory pages are being accessed by a workload and which are idle. This information can be useful for @@ -8,10 +15,14 @@ or deciding where to place the workload within a compute cluster. It is enabled by CONFIG_IDLE_PAGE_TRACKING=y. -USER API +.. _user_api: -The idle page tracking API is located at /sys/kernel/mm/page_idle. Currently, -it consists of the only read-write file, /sys/kernel/mm/page_idle/bitmap. +User API +======== + +The idle page tracking API is located at ``/sys/kernel/mm/page_idle``. +Currently, it consists of the only read-write file, +``/sys/kernel/mm/page_idle/bitmap``. The file implements a bitmap where each bit corresponds to a memory page. The bitmap is represented by an array of 8-byte integers, and the page at PFN #i is @@ -19,8 +30,9 @@ mapped to bit #i%64 of array element #i/64, byte order is native. When a bit is set, the corresponding page is idle. A page is considered idle if it has not been accessed since it was marked idle -(for more details on what "accessed" actually means see the IMPLEMENTATION -DETAILS section). To mark a page idle one has to set the bit corresponding to +(for more details on what "accessed" actually means see the :ref:`Implementation +Details <impl_details>` section). +To mark a page idle one has to set the bit corresponding to the page by writing to the file. A value written to the file is OR-ed with the current bitmap value. @@ -30,9 +42,9 @@ page types (e.g. SLAB pages) an attempt to mark a page idle is silently ignored, and hence such pages are never reported idle. For huge pages the idle flag is set only on the head page, so one has to read -/proc/kpageflags in order to correctly count idle huge pages. +``/proc/kpageflags`` in order to correctly count idle huge pages. -Reading from or writing to /sys/kernel/mm/page_idle/bitmap will return +Reading from or writing to ``/sys/kernel/mm/page_idle/bitmap`` will return -EINVAL if you are not starting the read/write on an 8-byte boundary, or if the size of the read/write is not a multiple of 8 bytes. Writing to this file beyond max PFN will return -ENXIO. @@ -41,21 +53,26 @@ That said, in order to estimate the amount of pages that are not used by a workload one should: 1. Mark all the workload's pages as idle by setting corresponding bits in - /sys/kernel/mm/page_idle/bitmap. The pages can be found by reading - /proc/pid/pagemap if the workload is represented by a process, or by - filtering out alien pages using /proc/kpagecgroup in case the workload is - placed in a memory cgroup. + ``/sys/kernel/mm/page_idle/bitmap``. The pages can be found by reading + ``/proc/pid/pagemap`` if the workload is represented by a process, or by + filtering out alien pages using ``/proc/kpagecgroup`` in case the workload + is placed in a memory cgroup. 2. Wait until the workload accesses its working set. - 3. Read /sys/kernel/mm/page_idle/bitmap and count the number of bits set. If - one wants to ignore certain types of pages, e.g. mlocked pages since they - are not reclaimable, he or she can filter them out using /proc/kpageflags. + 3. Read ``/sys/kernel/mm/page_idle/bitmap`` and count the number of bits set. + If one wants to ignore certain types of pages, e.g. mlocked pages since they + are not reclaimable, he or she can filter them out using + ``/proc/kpageflags``. + +See :ref:`Documentation/admin-guide/mm/pagemap.rst <pagemap>` for more +information about ``/proc/pid/pagemap``, ``/proc/kpageflags``, and +``/proc/kpagecgroup``. -See Documentation/vm/pagemap.txt for more information about /proc/pid/pagemap, -/proc/kpageflags, and /proc/kpagecgroup. +.. _impl_details: -IMPLEMENTATION DETAILS +Implementation Details +====================== The kernel internally keeps track of accesses to user memory pages in order to reclaim unreferenced pages first on memory shortage conditions. A page is @@ -77,7 +94,8 @@ When a dirty page is written to swap or disk as a result of memory reclaim or exceeding the dirty memory limit, it is not marked referenced. The idle memory tracking feature adds a new page flag, the Idle flag. This flag -is set manually, by writing to /sys/kernel/mm/page_idle/bitmap (see the USER API +is set manually, by writing to ``/sys/kernel/mm/page_idle/bitmap`` (see the +:ref:`User API <user_api>` section), and cleared automatically whenever a page is referenced as defined above. diff --git a/Documentation/admin-guide/mm/index.rst b/Documentation/admin-guide/mm/index.rst new file mode 100644 index 000000000000..ceead68c2df7 --- /dev/null +++ b/Documentation/admin-guide/mm/index.rst @@ -0,0 +1,36 @@ +================= +Memory Management +================= + +Linux memory management subsystem is responsible, as the name implies, +for managing the memory in the system. This includes implemnetation of +virtual memory and demand paging, memory allocation both for kernel +internal structures and user space programms, mapping of files into +processes address space and many other cool things. + +Linux memory management is a complex system with many configurable +settings. Most of these settings are available via ``/proc`` +filesystem and can be quired and adjusted using ``sysctl``. These APIs +are described in Documentation/sysctl/vm.txt and in `man 5 proc`_. + +.. _man 5 proc: http://man7.org/linux/man-pages/man5/proc.5.html + +Linux memory management has its own jargon and if you are not yet +familiar with it, consider reading +:ref:`Documentation/admin-guide/mm/concepts.rst <mm_concepts>`. + +Here we document in detail how to interact with various mechanisms in +the Linux memory management. + +.. toctree:: + :maxdepth: 1 + + concepts + hugetlbpage + idle_page_tracking + ksm + numa_memory_policy + pagemap + soft-dirty + transhuge + userfaultfd diff --git a/Documentation/admin-guide/mm/ksm.rst b/Documentation/admin-guide/mm/ksm.rst new file mode 100644 index 000000000000..9303786632d1 --- /dev/null +++ b/Documentation/admin-guide/mm/ksm.rst @@ -0,0 +1,189 @@ +.. _admin_guide_ksm: + +======================= +Kernel Samepage Merging +======================= + +Overview +======== + +KSM is a memory-saving de-duplication feature, enabled by CONFIG_KSM=y, +added to the Linux kernel in 2.6.32. See ``mm/ksm.c`` for its implementation, +and http://lwn.net/Articles/306704/ and http://lwn.net/Articles/330589/ + +KSM was originally developed for use with KVM (where it was known as +Kernel Shared Memory), to fit more virtual machines into physical memory, +by sharing the data common between them. But it can be useful to any +application which generates many instances of the same data. + +The KSM daemon ksmd periodically scans those areas of user memory +which have been registered with it, looking for pages of identical +content which can be replaced by a single write-protected page (which +is automatically copied if a process later wants to update its +content). The amount of pages that KSM daemon scans in a single pass +and the time between the passes are configured using :ref:`sysfs +intraface <ksm_sysfs>` + +KSM only merges anonymous (private) pages, never pagecache (file) pages. +KSM's merged pages were originally locked into kernel memory, but can now +be swapped out just like other user pages (but sharing is broken when they +are swapped back in: ksmd must rediscover their identity and merge again). + +Controlling KSM with madvise +============================ + +KSM only operates on those areas of address space which an application +has advised to be likely candidates for merging, by using the madvise(2) +system call:: + + int madvise(addr, length, MADV_MERGEABLE) + +The app may call + +:: + + int madvise(addr, length, MADV_UNMERGEABLE) + +to cancel that advice and restore unshared pages: whereupon KSM +unmerges whatever it merged in that range. Note: this unmerging call +may suddenly require more memory than is available - possibly failing +with EAGAIN, but more probably arousing the Out-Of-Memory killer. + +If KSM is not configured into the running kernel, madvise MADV_MERGEABLE +and MADV_UNMERGEABLE simply fail with EINVAL. If the running kernel was +built with CONFIG_KSM=y, those calls will normally succeed: even if the +the KSM daemon is not currently running, MADV_MERGEABLE still registers +the range for whenever the KSM daemon is started; even if the range +cannot contain any pages which KSM could actually merge; even if +MADV_UNMERGEABLE is applied to a range which was never MADV_MERGEABLE. + +If a region of memory must be split into at least one new MADV_MERGEABLE +or MADV_UNMERGEABLE region, the madvise may return ENOMEM if the process +will exceed ``vm.max_map_count`` (see Documentation/sysctl/vm.txt). + +Like other madvise calls, they are intended for use on mapped areas of +the user address space: they will report ENOMEM if the specified range +includes unmapped gaps (though working on the intervening mapped areas), +and might fail with EAGAIN if not enough memory for internal structures. + +Applications should be considerate in their use of MADV_MERGEABLE, +restricting its use to areas likely to benefit. KSM's scans may use a lot +of processing power: some installations will disable KSM for that reason. + +.. _ksm_sysfs: + +KSM daemon sysfs interface +========================== + +The KSM daemon is controlled by sysfs files in ``/sys/kernel/mm/ksm/``, +readable by all but writable only by root: + +pages_to_scan + how many pages to scan before ksmd goes to sleep + e.g. ``echo 100 > /sys/kernel/mm/ksm/pages_to_scan``. + + Default: 100 (chosen for demonstration purposes) + +sleep_millisecs + how many milliseconds ksmd should sleep before next scan + e.g. ``echo 20 > /sys/kernel/mm/ksm/sleep_millisecs`` + + Default: 20 (chosen for demonstration purposes) + +merge_across_nodes + specifies if pages from different NUMA nodes can be merged. + When set to 0, ksm merges only pages which physically reside + in the memory area of same NUMA node. That brings lower + latency to access of shared pages. Systems with more nodes, at + significant NUMA distances, are likely to benefit from the + lower latency of setting 0. Smaller systems, which need to + minimize memory usage, are likely to benefit from the greater + sharing of setting 1 (default). You may wish to compare how + your system performs under each setting, before deciding on + which to use. ``merge_across_nodes`` setting can be changed only + when there are no ksm shared pages in the system: set run 2 to + unmerge pages first, then to 1 after changing + ``merge_across_nodes``, to remerge according to the new setting. + + Default: 1 (merging across nodes as in earlier releases) + +run + * set to 0 to stop ksmd from running but keep merged pages, + * set to 1 to run ksmd e.g. ``echo 1 > /sys/kernel/mm/ksm/run``, + * set to 2 to stop ksmd and unmerge all pages currently merged, but + leave mergeable areas registered for next run. + + Default: 0 (must be changed to 1 to activate KSM, except if + CONFIG_SYSFS is disabled) + +use_zero_pages + specifies whether empty pages (i.e. allocated pages that only + contain zeroes) should be treated specially. When set to 1, + empty pages are merged with the kernel zero page(s) instead of + with each other as it would happen normally. This can improve + the performance on architectures with coloured zero pages, + depending on the workload. Care should be taken when enabling + this setting, as it can potentially degrade the performance of + KSM for some workloads, for example if the checksums of pages + candidate for merging match the checksum of an empty + page. This setting can be changed at any time, it is only + effective for pages merged after the change. + + Default: 0 (normal KSM behaviour as in earlier releases) + +max_page_sharing + Maximum sharing allowed for each KSM page. This enforces a + deduplication limit to avoid high latency for virtual memory + operations that involve traversal of the virtual mappings that + share the KSM page. The minimum value is 2 as a newly created + KSM page will have at least two sharers. The higher this value + the faster KSM will merge the memory and the higher the + deduplication factor will be, but the slower the worst case + virtual mappings traversal could be for any given KSM + page. Slowing down this traversal means there will be higher + latency for certain virtual memory operations happening during + swapping, compaction, NUMA balancing and page migration, in + turn decreasing responsiveness for the caller of those virtual + memory operations. The scheduler latency of other tasks not + involved with the VM operations doing the virtual mappings + traversal is not affected by this parameter as these + traversals are always schedule friendly themselves. + +stable_node_chains_prune_millisecs + specifies how frequently KSM checks the metadata of the pages + that hit the deduplication limit for stale information. + Smaller milllisecs values will free up the KSM metadata with + lower latency, but they will make ksmd use more CPU during the + scan. It's a noop if not a single KSM page hit the + ``max_page_sharing`` yet. + +The effectiveness of KSM and MADV_MERGEABLE is shown in ``/sys/kernel/mm/ksm/``: + +pages_shared + how many shared pages are being used +pages_sharing + how many more sites are sharing them i.e. how much saved +pages_unshared + how many pages unique but repeatedly checked for merging +pages_volatile + how many pages changing too fast to be placed in a tree +full_scans + how many times all mergeable areas have been scanned +stable_node_chains + the number of KSM pages that hit the ``max_page_sharing`` limit +stable_node_dups + number of duplicated KSM pages + +A high ratio of ``pages_sharing`` to ``pages_shared`` indicates good +sharing, but a high ratio of ``pages_unshared`` to ``pages_sharing`` +indicates wasted effort. ``pages_volatile`` embraces several +different kinds of activity, but a high proportion there would also +indicate poor use of madvise MADV_MERGEABLE. + +The maximum possible ``pages_sharing/pages_shared`` ratio is limited by the +``max_page_sharing`` tunable. To increase the ratio ``max_page_sharing`` must +be increased accordingly. + +-- +Izik Eidus, +Hugh Dickins, 17 Nov 2009 diff --git a/Documentation/admin-guide/mm/numa_memory_policy.rst b/Documentation/admin-guide/mm/numa_memory_policy.rst new file mode 100644 index 000000000000..d78c5b315f72 --- /dev/null +++ b/Documentation/admin-guide/mm/numa_memory_policy.rst @@ -0,0 +1,495 @@ +.. _numa_memory_policy: + +================== +NUMA Memory Policy +================== + +What is NUMA Memory Policy? +============================ + +In the Linux kernel, "memory policy" determines from which node the kernel will +allocate memory in a NUMA system or in an emulated NUMA system. Linux has +supported platforms with Non-Uniform Memory Access architectures since 2.4.?. +The current memory policy support was added to Linux 2.6 around May 2004. This +document attempts to describe the concepts and APIs of the 2.6 memory policy +support. + +Memory policies should not be confused with cpusets +(``Documentation/cgroup-v1/cpusets.txt``) +which is an administrative mechanism for restricting the nodes from which +memory may be allocated by a set of processes. Memory policies are a +programming interface that a NUMA-aware application can take advantage of. When +both cpusets and policies are applied to a task, the restrictions of the cpuset +takes priority. See :ref:`Memory Policies and cpusets <mem_pol_and_cpusets>` +below for more details. + +Memory Policy Concepts +====================== + +Scope of Memory Policies +------------------------ + +The Linux kernel supports _scopes_ of memory policy, described here from +most general to most specific: + +System Default Policy + this policy is "hard coded" into the kernel. It is the policy + that governs all page allocations that aren't controlled by + one of the more specific policy scopes discussed below. When + the system is "up and running", the system default policy will + use "local allocation" described below. However, during boot + up, the system default policy will be set to interleave + allocations across all nodes with "sufficient" memory, so as + not to overload the initial boot node with boot-time + allocations. + +Task/Process Policy + this is an optional, per-task policy. When defined for a + specific task, this policy controls all page allocations made + by or on behalf of the task that aren't controlled by a more + specific scope. If a task does not define a task policy, then + all page allocations that would have been controlled by the + task policy "fall back" to the System Default Policy. + + The task policy applies to the entire address space of a task. Thus, + it is inheritable, and indeed is inherited, across both fork() + [clone() w/o the CLONE_VM flag] and exec*(). This allows a parent task + to establish the task policy for a child task exec()'d from an + executable image that has no awareness of memory policy. See the + :ref:`Memory Policy APIs <memory_policy_apis>` section, + below, for an overview of the system call + that a task may use to set/change its task/process policy. + + In a multi-threaded task, task policies apply only to the thread + [Linux kernel task] that installs the policy and any threads + subsequently created by that thread. Any sibling threads existing + at the time a new task policy is installed retain their current + policy. + + A task policy applies only to pages allocated after the policy is + installed. Any pages already faulted in by the task when the task + changes its task policy remain where they were allocated based on + the policy at the time they were allocated. + +.. _vma_policy: + +VMA Policy + A "VMA" or "Virtual Memory Area" refers to a range of a task's + virtual address space. A task may define a specific policy for a range + of its virtual address space. See the + :ref:`Memory Policy APIs <memory_policy_apis>` section, + below, for an overview of the mbind() system call used to set a VMA + policy. + + A VMA policy will govern the allocation of pages that back + this region of the address space. Any regions of the task's + address space that don't have an explicit VMA policy will fall + back to the task policy, which may itself fall back to the + System Default Policy. + + VMA policies have a few complicating details: + + * VMA policy applies ONLY to anonymous pages. These include + pages allocated for anonymous segments, such as the task + stack and heap, and any regions of the address space + mmap()ed with the MAP_ANONYMOUS flag. If a VMA policy is + applied to a file mapping, it will be ignored if the mapping + used the MAP_SHARED flag. If the file mapping used the + MAP_PRIVATE flag, the VMA policy will only be applied when + an anonymous page is allocated on an attempt to write to the + mapping-- i.e., at Copy-On-Write. + + * VMA policies are shared between all tasks that share a + virtual address space--a.k.a. threads--independent of when + the policy is installed; and they are inherited across + fork(). However, because VMA policies refer to a specific + region of a task's address space, and because the address + space is discarded and recreated on exec*(), VMA policies + are NOT inheritable across exec(). Thus, only NUMA-aware + applications may use VMA policies. + + * A task may install a new VMA policy on a sub-range of a + previously mmap()ed region. When this happens, Linux splits + the existing virtual memory area into 2 or 3 VMAs, each with + it's own policy. + + * By default, VMA policy applies only to pages allocated after + the policy is installed. Any pages already faulted into the + VMA range remain where they were allocated based on the + policy at the time they were allocated. However, since + 2.6.16, Linux supports page migration via the mbind() system + call, so that page contents can be moved to match a newly + installed policy. + +Shared Policy + Conceptually, shared policies apply to "memory objects" mapped + shared into one or more tasks' distinct address spaces. An + application installs shared policies the same way as VMA + policies--using the mbind() system call specifying a range of + virtual addresses that map the shared object. However, unlike + VMA policies, which can be considered to be an attribute of a + range of a task's address space, shared policies apply + directly to the shared object. Thus, all tasks that attach to + the object share the policy, and all pages allocated for the + shared object, by any task, will obey the shared policy. + + As of 2.6.22, only shared memory segments, created by shmget() or + mmap(MAP_ANONYMOUS|MAP_SHARED), support shared policy. When shared + policy support was added to Linux, the associated data structures were + added to hugetlbfs shmem segments. At the time, hugetlbfs did not + support allocation at fault time--a.k.a lazy allocation--so hugetlbfs + shmem segments were never "hooked up" to the shared policy support. + Although hugetlbfs segments now support lazy allocation, their support + for shared policy has not been completed. + + As mentioned above in :ref:`VMA policies <vma_policy>` section, + allocations of page cache pages for regular files mmap()ed + with MAP_SHARED ignore any VMA policy installed on the virtual + address range backed by the shared file mapping. Rather, + shared page cache pages, including pages backing private + mappings that have not yet been written by the task, follow + task policy, if any, else System Default Policy. + + The shared policy infrastructure supports different policies on subset + ranges of the shared object. However, Linux still splits the VMA of + the task that installs the policy for each range of distinct policy. + Thus, different tasks that attach to a shared memory segment can have + different VMA configurations mapping that one shared object. This + can be seen by examining the /proc/<pid>/numa_maps of tasks sharing + a shared memory region, when one task has installed shared policy on + one or more ranges of the region. + +Components of Memory Policies +----------------------------- + +A NUMA memory policy consists of a "mode", optional mode flags, and +an optional set of nodes. The mode determines the behavior of the +policy, the optional mode flags determine the behavior of the mode, +and the optional set of nodes can be viewed as the arguments to the +policy behavior. + +Internally, memory policies are implemented by a reference counted +structure, struct mempolicy. Details of this structure will be +discussed in context, below, as required to explain the behavior. + +NUMA memory policy supports the following 4 behavioral modes: + +Default Mode--MPOL_DEFAULT + This mode is only used in the memory policy APIs. Internally, + MPOL_DEFAULT is converted to the NULL memory policy in all + policy scopes. Any existing non-default policy will simply be + removed when MPOL_DEFAULT is specified. As a result, + MPOL_DEFAULT means "fall back to the next most specific policy + scope." + + For example, a NULL or default task policy will fall back to the + system default policy. A NULL or default vma policy will fall + back to the task policy. + + When specified in one of the memory policy APIs, the Default mode + does not use the optional set of nodes. + + It is an error for the set of nodes specified for this policy to + be non-empty. + +MPOL_BIND + This mode specifies that memory must come from the set of + nodes specified by the policy. Memory will be allocated from + the node in the set with sufficient free memory that is + closest to the node where the allocation takes place. + +MPOL_PREFERRED + This mode specifies that the allocation should be attempted + from the single node specified in the policy. If that + allocation fails, the kernel will search other nodes, in order + of increasing distance from the preferred node based on + information provided by the platform firmware. + + Internally, the Preferred policy uses a single node--the + preferred_node member of struct mempolicy. When the internal + mode flag MPOL_F_LOCAL is set, the preferred_node is ignored + and the policy is interpreted as local allocation. "Local" + allocation policy can be viewed as a Preferred policy that + starts at the node containing the cpu where the allocation + takes place. + + It is possible for the user to specify that local allocation + is always preferred by passing an empty nodemask with this + mode. If an empty nodemask is passed, the policy cannot use + the MPOL_F_STATIC_NODES or MPOL_F_RELATIVE_NODES flags + described below. + +MPOL_INTERLEAVED + This mode specifies that page allocations be interleaved, on a + page granularity, across the nodes specified in the policy. + This mode also behaves slightly differently, based on the + context where it is used: + + For allocation of anonymous pages and shared memory pages, + Interleave mode indexes the set of nodes specified by the + policy using the page offset of the faulting address into the + segment [VMA] containing the address modulo the number of + nodes specified by the policy. It then attempts to allocate a + page, starting at the selected node, as if the node had been + specified by a Preferred policy or had been selected by a + local allocation. That is, allocation will follow the per + node zonelist. + + For allocation of page cache pages, Interleave mode indexes + the set of nodes specified by the policy using a node counter + maintained per task. This counter wraps around to the lowest + specified node after it reaches the highest specified node. + This will tend to spread the pages out over the nodes + specified by the policy based on the order in which they are + allocated, rather than based on any page offset into an + address range or file. During system boot up, the temporary + interleaved system default policy works in this mode. + +NUMA memory policy supports the following optional mode flags: + +MPOL_F_STATIC_NODES + This flag specifies that the nodemask passed by + the user should not be remapped if the task or VMA's set of allowed + nodes changes after the memory policy has been defined. + + Without this flag, any time a mempolicy is rebound because of a + change in the set of allowed nodes, the node (Preferred) or + nodemask (Bind, Interleave) is remapped to the new set of + allowed nodes. This may result in nodes being used that were + previously undesired. + + With this flag, if the user-specified nodes overlap with the + nodes allowed by the task's cpuset, then the memory policy is + applied to their intersection. If the two sets of nodes do not + overlap, the Default policy is used. + + For example, consider a task that is attached to a cpuset with + mems 1-3 that sets an Interleave policy over the same set. If + the cpuset's mems change to 3-5, the Interleave will now occur + over nodes 3, 4, and 5. With this flag, however, since only node + 3 is allowed from the user's nodemask, the "interleave" only + occurs over that node. If no nodes from the user's nodemask are + now allowed, the Default behavior is used. + + MPOL_F_STATIC_NODES cannot be combined with the + MPOL_F_RELATIVE_NODES flag. It also cannot be used for + MPOL_PREFERRED policies that were created with an empty nodemask + (local allocation). + +MPOL_F_RELATIVE_NODES + This flag specifies that the nodemask passed + by the user will be mapped relative to the set of the task or VMA's + set of allowed nodes. The kernel stores the user-passed nodemask, + and if the allowed nodes changes, then that original nodemask will + be remapped relative to the new set of allowed nodes. + + Without this flag (and without MPOL_F_STATIC_NODES), anytime a + mempolicy is rebound because of a change in the set of allowed + nodes, the node (Preferred) or nodemask (Bind, Interleave) is + remapped to the new set of allowed nodes. That remap may not + preserve the relative nature of the user's passed nodemask to its + set of allowed nodes upon successive rebinds: a nodemask of + 1,3,5 may be remapped to 7-9 and then to 1-3 if the set of + allowed nodes is restored to its original state. + + With this flag, the remap is done so that the node numbers from + the user's passed nodemask are relative to the set of allowed + nodes. In other words, if nodes 0, 2, and 4 are set in the user's + nodemask, the policy will be effected over the first (and in the + Bind or Interleave case, the third and fifth) nodes in the set of + allowed nodes. The nodemask passed by the user represents nodes + relative to task or VMA's set of allowed nodes. + + If the user's nodemask includes nodes that are outside the range + of the new set of allowed nodes (for example, node 5 is set in + the user's nodemask when the set of allowed nodes is only 0-3), + then the remap wraps around to the beginning of the nodemask and, + if not already set, sets the node in the mempolicy nodemask. + + For example, consider a task that is attached to a cpuset with + mems 2-5 that sets an Interleave policy over the same set with + MPOL_F_RELATIVE_NODES. If the cpuset's mems change to 3-7, the + interleave now occurs over nodes 3,5-7. If the cpuset's mems + then change to 0,2-3,5, then the interleave occurs over nodes + 0,2-3,5. + + Thanks to the consistent remapping, applications preparing + nodemasks to specify memory policies using this flag should + disregard their current, actual cpuset imposed memory placement + and prepare the nodemask as if they were always located on + memory nodes 0 to N-1, where N is the number of memory nodes the + policy is intended to manage. Let the kernel then remap to the + set of memory nodes allowed by the task's cpuset, as that may + change over time. + + MPOL_F_RELATIVE_NODES cannot be combined with the + MPOL_F_STATIC_NODES flag. It also cannot be used for + MPOL_PREFERRED policies that were created with an empty nodemask + (local allocation). + +Memory Policy Reference Counting +================================ + +To resolve use/free races, struct mempolicy contains an atomic reference +count field. Internal interfaces, mpol_get()/mpol_put() increment and +decrement this reference count, respectively. mpol_put() will only free +the structure back to the mempolicy kmem cache when the reference count +goes to zero. + +When a new memory policy is allocated, its reference count is initialized +to '1', representing the reference held by the task that is installing the +new policy. When a pointer to a memory policy structure is stored in another +structure, another reference is added, as the task's reference will be dropped +on completion of the policy installation. + +During run-time "usage" of the policy, we attempt to minimize atomic operations +on the reference count, as this can lead to cache lines bouncing between cpus +and NUMA nodes. "Usage" here means one of the following: + +1) querying of the policy, either by the task itself [using the get_mempolicy() + API discussed below] or by another task using the /proc/<pid>/numa_maps + interface. + +2) examination of the policy to determine the policy mode and associated node + or node lists, if any, for page allocation. This is considered a "hot + path". Note that for MPOL_BIND, the "usage" extends across the entire + allocation process, which may sleep during page reclaimation, because the + BIND policy nodemask is used, by reference, to filter ineligible nodes. + +We can avoid taking an extra reference during the usages listed above as +follows: + +1) we never need to get/free the system default policy as this is never + changed nor freed, once the system is up and running. + +2) for querying the policy, we do not need to take an extra reference on the + target task's task policy nor vma policies because we always acquire the + task's mm's mmap_sem for read during the query. The set_mempolicy() and + mbind() APIs [see below] always acquire the mmap_sem for write when + installing or replacing task or vma policies. Thus, there is no possibility + of a task or thread freeing a policy while another task or thread is + querying it. + +3) Page allocation usage of task or vma policy occurs in the fault path where + we hold them mmap_sem for read. Again, because replacing the task or vma + policy requires that the mmap_sem be held for write, the policy can't be + freed out from under us while we're using it for page allocation. + +4) Shared policies require special consideration. One task can replace a + shared memory policy while another task, with a distinct mmap_sem, is + querying or allocating a page based on the policy. To resolve this + potential race, the shared policy infrastructure adds an extra reference + to the shared policy during lookup while holding a spin lock on the shared + policy management structure. This requires that we drop this extra + reference when we're finished "using" the policy. We must drop the + extra reference on shared policies in the same query/allocation paths + used for non-shared policies. For this reason, shared policies are marked + as such, and the extra reference is dropped "conditionally"--i.e., only + for shared policies. + + Because of this extra reference counting, and because we must lookup + shared policies in a tree structure under spinlock, shared policies are + more expensive to use in the page allocation path. This is especially + true for shared policies on shared memory regions shared by tasks running + on different NUMA nodes. This extra overhead can be avoided by always + falling back to task or system default policy for shared memory regions, + or by prefaulting the entire shared memory region into memory and locking + it down. However, this might not be appropriate for all applications. + +.. _memory_policy_apis: + +Memory Policy APIs +================== + +Linux supports 3 system calls for controlling memory policy. These APIS +always affect only the calling task, the calling task's address space, or +some shared object mapped into the calling task's address space. + +.. note:: + the headers that define these APIs and the parameter data types for + user space applications reside in a package that is not part of the + Linux kernel. The kernel system call interfaces, with the 'sys\_' + prefix, are defined in <linux/syscalls.h>; the mode and flag + definitions are defined in <linux/mempolicy.h>. + +Set [Task] Memory Policy:: + + long set_mempolicy(int mode, const unsigned long *nmask, + unsigned long maxnode); + +Set's the calling task's "task/process memory policy" to mode +specified by the 'mode' argument and the set of nodes defined by +'nmask'. 'nmask' points to a bit mask of node ids containing at least +'maxnode' ids. Optional mode flags may be passed by combining the +'mode' argument with the flag (for example: MPOL_INTERLEAVE | +MPOL_F_STATIC_NODES). + +See the set_mempolicy(2) man page for more details + + +Get [Task] Memory Policy or Related Information:: + + long get_mempolicy(int *mode, + const unsigned long *nmask, unsigned long maxnode, + void *addr, int flags); + +Queries the "task/process memory policy" of the calling task, or the +policy or location of a specified virtual address, depending on the +'flags' argument. + +See the get_mempolicy(2) man page for more details + + +Install VMA/Shared Policy for a Range of Task's Address Space:: + + long mbind(void *start, unsigned long len, int mode, + const unsigned long *nmask, unsigned long maxnode, + unsigned flags); + +mbind() installs the policy specified by (mode, nmask, maxnodes) as a +VMA policy for the range of the calling task's address space specified +by the 'start' and 'len' arguments. Additional actions may be +requested via the 'flags' argument. + +See the mbind(2) man page for more details. + +Memory Policy Command Line Interface +==================================== + +Although not strictly part of the Linux implementation of memory policy, +a command line tool, numactl(8), exists that allows one to: + ++ set the task policy for a specified program via set_mempolicy(2), fork(2) and + exec(2) + ++ set the shared policy for a shared memory segment via mbind(2) + +The numactl(8) tool is packaged with the run-time version of the library +containing the memory policy system call wrappers. Some distributions +package the headers and compile-time libraries in a separate development +package. + +.. _mem_pol_and_cpusets: + +Memory Policies and cpusets +=========================== + +Memory policies work within cpusets as described above. For memory policies +that require a node or set of nodes, the nodes are restricted to the set of +nodes whose memories are allowed by the cpuset constraints. If the nodemask +specified for the policy contains nodes that are not allowed by the cpuset and +MPOL_F_RELATIVE_NODES is not used, the intersection of the set of nodes +specified for the policy and the set of nodes with memory is used. If the +result is the empty set, the policy is considered invalid and cannot be +installed. If MPOL_F_RELATIVE_NODES is used, the policy's nodes are mapped +onto and folded into the task's set of allowed nodes as previously described. + +The interaction of memory policies and cpusets can be problematic when tasks +in two cpusets share access to a memory region, such as shared memory segments +created by shmget() of mmap() with the MAP_ANONYMOUS and MAP_SHARED flags, and +any of the tasks install shared policy on the region, only nodes whose +memories are allowed in both cpusets may be used in the policies. Obtaining +this information requires "stepping outside" the memory policy APIs to use the +cpuset information and requires that one know in what cpusets other task might +be attaching to the shared region. Furthermore, if the cpusets' allowed +memory sets are disjoint, "local" allocation is the only valid policy. diff --git a/Documentation/vm/pagemap.txt b/Documentation/admin-guide/mm/pagemap.rst index eafcefa15261..577af85beb41 100644 --- a/Documentation/vm/pagemap.txt +++ b/Documentation/admin-guide/mm/pagemap.rst @@ -1,21 +1,25 @@ -pagemap, from the userspace perspective ---------------------------------------- +.. _pagemap: + +============================= +Examining Process Page Tables +============================= pagemap is a new (as of 2.6.25) set of interfaces in the kernel that allow userspace programs to examine the page tables and related information by -reading files in /proc. +reading files in ``/proc``. There are four components to pagemap: - * /proc/pid/pagemap. This file lets a userspace process find out which + * ``/proc/pid/pagemap``. This file lets a userspace process find out which physical frame each virtual page is mapped to. It contains one 64-bit value for each virtual page, containing the following data (from - fs/proc/task_mmu.c, above pagemap_read): + ``fs/proc/task_mmu.c``, above pagemap_read): * Bits 0-54 page frame number (PFN) if present * Bits 0-4 swap type if swapped * Bits 5-54 swap offset if swapped - * Bit 55 pte is soft-dirty (see Documentation/vm/soft-dirty.txt) + * Bit 55 pte is soft-dirty (see + :ref:`Documentation/admin-guide/mm/soft-dirty.rst <soft_dirty>`) * Bit 56 page exclusively mapped (since 4.2) * Bits 57-60 zero * Bit 61 page is file-page or shared-anon (since 3.5) @@ -33,28 +37,28 @@ There are four components to pagemap: precisely which pages are mapped (or in swap) and comparing mapped pages between processes. - Efficient users of this interface will use /proc/pid/maps to + Efficient users of this interface will use ``/proc/pid/maps`` to determine which areas of memory are actually mapped and llseek to skip over unmapped regions. - * /proc/kpagecount. This file contains a 64-bit count of the number of + * ``/proc/kpagecount``. This file contains a 64-bit count of the number of times each page is mapped, indexed by PFN. - * /proc/kpageflags. This file contains a 64-bit set of flags for each + * ``/proc/kpageflags``. This file contains a 64-bit set of flags for each page, indexed by PFN. - The flags are (from fs/proc/page.c, above kpageflags_read): - - 0. LOCKED - 1. ERROR - 2. REFERENCED - 3. UPTODATE - 4. DIRTY - 5. LRU - 6. ACTIVE - 7. SLAB - 8. WRITEBACK - 9. RECLAIM + The flags are (from ``fs/proc/page.c``, above kpageflags_read): + + 0. LOCKED + 1. ERROR + 2. REFERENCED + 3. UPTODATE + 4. DIRTY + 5. LRU + 6. ACTIVE + 7. SLAB + 8. WRITEBACK + 9. RECLAIM 10. BUDDY 11. MMAP 12. ANON @@ -72,98 +76,111 @@ There are four components to pagemap: 24. ZERO_PAGE 25. IDLE - * /proc/kpagecgroup. This file contains a 64-bit inode number of the + * ``/proc/kpagecgroup``. This file contains a 64-bit inode number of the memory cgroup each page is charged to, indexed by PFN. Only available when CONFIG_MEMCG is set. -Short descriptions to the page flags: - - 0. LOCKED - page is being locked for exclusive access, eg. by undergoing read/write IO - - 7. SLAB - page is managed by the SLAB/SLOB/SLUB/SLQB kernel memory allocator - When compound page is used, SLUB/SLQB will only set this flag on the head - page; SLOB will not flag it at all. +Short descriptions to the page flags +==================================== -10. BUDDY +0 - LOCKED + page is being locked for exclusive access, e.g. by undergoing read/write IO +7 - SLAB + page is managed by the SLAB/SLOB/SLUB/SLQB kernel memory allocator + When compound page is used, SLUB/SLQB will only set this flag on the head + page; SLOB will not flag it at all. +10 - BUDDY a free memory block managed by the buddy system allocator The buddy system organizes free memory in blocks of various orders. An order N block has 2^N physically contiguous pages, with the BUDDY flag set for and _only_ for the first page. - -15. COMPOUND_HEAD -16. COMPOUND_TAIL +15 - COMPOUND_HEAD A compound page with order N consists of 2^N physically contiguous pages. A compound page with order 2 takes the form of "HTTT", where H donates its head page and T donates its tail page(s). The major consumers of compound - pages are hugeTLB pages (Documentation/vm/hugetlbpage.txt), the SLUB etc. - memory allocators and various device drivers. However in this interface, - only huge/giga pages are made visible to end users. -17. HUGE + pages are hugeTLB pages + (:ref:`Documentation/admin-guide/mm/hugetlbpage.rst <hugetlbpage>`), + the SLUB etc. memory allocators and various device drivers. + However in this interface, only huge/giga pages are made visible + to end users. +16 - COMPOUND_TAIL + A compound page tail (see description above). +17 - HUGE this is an integral part of a HugeTLB page - -19. HWPOISON +19 - HWPOISON hardware detected memory corruption on this page: don't touch the data! - -20. NOPAGE +20 - NOPAGE no page frame exists at the requested address - -21. KSM +21 - KSM identical memory pages dynamically shared between one or more processes - -22. THP +22 - THP contiguous pages which construct transparent hugepages - -23. BALLOON +23 - BALLOON balloon compaction page - -24. ZERO_PAGE +24 - ZERO_PAGE zero page for pfn_zero or huge_zero page - -25. IDLE +25 - IDLE page has not been accessed since it was marked idle (see - Documentation/vm/idle_page_tracking.txt). Note that this flag may be - stale in case the page was accessed via a PTE. To make sure the flag - is up-to-date one has to read /sys/kernel/mm/page_idle/bitmap first. - - [IO related page flags] - 1. ERROR IO error occurred - 3. UPTODATE page has up-to-date data - ie. for file backed page: (in-memory data revision >= on-disk one) - 4. DIRTY page has been written to, hence contains new data - ie. for file backed page: (in-memory data revision > on-disk one) - 8. WRITEBACK page is being synced to disk - - [LRU related page flags] - 5. LRU page is in one of the LRU lists - 6. ACTIVE page is in the active LRU list -18. UNEVICTABLE page is in the unevictable (non-)LRU list - It is somehow pinned and not a candidate for LRU page reclaims, - eg. ramfs pages, shmctl(SHM_LOCK) and mlock() memory segments - 2. REFERENCED page has been referenced since last LRU list enqueue/requeue - 9. RECLAIM page will be reclaimed soon after its pageout IO completed -11. MMAP a memory mapped page -12. ANON a memory mapped page that is not part of a file -13. SWAPCACHE page is mapped to swap space, ie. has an associated swap entry -14. SWAPBACKED page is backed by swap/RAM + :ref:`Documentation/admin-guide/mm/idle_page_tracking.rst <idle_page_tracking>`). + Note that this flag may be stale in case the page was accessed via + a PTE. To make sure the flag is up-to-date one has to read + ``/sys/kernel/mm/page_idle/bitmap`` first. + +IO related page flags +--------------------- + +1 - ERROR + IO error occurred +3 - UPTODATE + page has up-to-date data + ie. for file backed page: (in-memory data revision >= on-disk one) +4 - DIRTY + page has been written to, hence contains new data + i.e. for file backed page: (in-memory data revision > on-disk one) +8 - WRITEBACK + page is being synced to disk + +LRU related page flags +---------------------- + +5 - LRU + page is in one of the LRU lists +6 - ACTIVE + page is in the active LRU list +18 - UNEVICTABLE + page is in the unevictable (non-)LRU list It is somehow pinned and + not a candidate for LRU page reclaims, e.g. ramfs pages, + shmctl(SHM_LOCK) and mlock() memory segments +2 - REFERENCED + page has been referenced since last LRU list enqueue/requeue +9 - RECLAIM + page will be reclaimed soon after its pageout IO completed +11 - MMAP + a memory mapped page +12 - ANON + a memory mapped page that is not part of a file +13 - SWAPCACHE + page is mapped to swap space, i.e. has an associated swap entry +14 - SWAPBACKED + page is backed by swap/RAM The page-types tool in the tools/vm directory can be used to query the above flags. -Using pagemap to do something useful: +Using pagemap to do something useful +==================================== The general procedure for using pagemap to find out about a process' memory usage goes like this: - 1. Read /proc/pid/maps to determine which parts of the memory space are + 1. Read ``/proc/pid/maps`` to determine which parts of the memory space are mapped to what. 2. Select the maps you are interested in -- all of them, or a particular library, or the stack or the heap, etc. - 3. Open /proc/pid/pagemap and seek to the pages you would like to examine. + 3. Open ``/proc/pid/pagemap`` and seek to the pages you would like to examine. 4. Read a u64 for each page from pagemap. - 5. Open /proc/kpagecount and/or /proc/kpageflags. For each PFN you just - read, seek to that entry in the file, and read the data you want. + 5. Open ``/proc/kpagecount`` and/or ``/proc/kpageflags``. For each PFN you + just read, seek to that entry in the file, and read the data you want. For example, to find the "unique set size" (USS), which is the amount of memory that a process is using that is not shared with any other process, @@ -171,7 +188,8 @@ you can go through every map in the process, find the PFNs, look those up in kpagecount, and tally up the number of pages that are only referenced once. -Other notes: +Other notes +=========== Reading from any of the files will return -EINVAL if you are not starting the read on an 8-byte boundary (e.g., if you sought an odd number of bytes diff --git a/Documentation/vm/soft-dirty.txt b/Documentation/admin-guide/mm/soft-dirty.rst index 55684d11a1e8..cb0cfd6672fa 100644 --- a/Documentation/vm/soft-dirty.txt +++ b/Documentation/admin-guide/mm/soft-dirty.rst @@ -1,34 +1,38 @@ - SOFT-DIRTY PTEs +.. _soft_dirty: - The soft-dirty is a bit on a PTE which helps to track which pages a task +=============== +Soft-Dirty PTEs +=============== + +The soft-dirty is a bit on a PTE which helps to track which pages a task writes to. In order to do this tracking one should 1. Clear soft-dirty bits from the task's PTEs. - This is done by writing "4" into the /proc/PID/clear_refs file of the + This is done by writing "4" into the ``/proc/PID/clear_refs`` file of the task in question. 2. Wait some time. 3. Read soft-dirty bits from the PTEs. - This is done by reading from the /proc/PID/pagemap. The bit 55 of the + This is done by reading from the ``/proc/PID/pagemap``. The bit 55 of the 64-bit qword is the soft-dirty one. If set, the respective PTE was written to since step 1. - Internally, to do this tracking, the writable bit is cleared from PTEs +Internally, to do this tracking, the writable bit is cleared from PTEs when the soft-dirty bit is cleared. So, after this, when the task tries to modify a page at some virtual address the #PF occurs and the kernel sets the soft-dirty bit on the respective PTE. - Note, that although all the task's address space is marked as r/o after the +Note, that although all the task's address space is marked as r/o after the soft-dirty bits clear, the #PF-s that occur after that are processed fast. This is so, since the pages are still mapped to physical memory, and thus all the kernel does is finds this fact out and puts both writable and soft-dirty bits on the PTE. - While in most cases tracking memory changes by #PF-s is more than enough +While in most cases tracking memory changes by #PF-s is more than enough there is still a scenario when we can lose soft dirty bits -- a task unmaps a previously mapped memory region and then maps a new one at exactly the same place. When unmap is called, the kernel internally clears PTE values @@ -36,7 +40,7 @@ including soft dirty bits. To notify user space application about such memory region renewal the kernel always marks new memory regions (and expanded regions) as soft dirty. - This feature is actively used by the checkpoint-restore project. You +This feature is actively used by the checkpoint-restore project. You can find more details about it on http://criu.org diff --git a/Documentation/admin-guide/mm/transhuge.rst b/Documentation/admin-guide/mm/transhuge.rst new file mode 100644 index 000000000000..7ab93a8404b9 --- /dev/null +++ b/Documentation/admin-guide/mm/transhuge.rst @@ -0,0 +1,418 @@ +.. _admin_guide_transhuge: + +============================ +Transparent Hugepage Support +============================ + +Objective +========= + +Performance critical computing applications dealing with large memory +working sets are already running on top of libhugetlbfs and in turn +hugetlbfs. Transparent HugePage Support (THP) is an alternative mean of +using huge pages for the backing of virtual memory with huge pages +that supports the automatic promotion and demotion of page sizes and +without the shortcomings of hugetlbfs. + +Currently THP only works for anonymous memory mappings and tmpfs/shmem. +But in the future it can expand to other filesystems. + +.. note:: + in the examples below we presume that the basic page size is 4K and + the huge page size is 2M, although the actual numbers may vary + depending on the CPU architecture. + +The reason applications are running faster is because of two +factors. The first factor is almost completely irrelevant and it's not +of significant interest because it'll also have the downside of +requiring larger clear-page copy-page in page faults which is a +potentially negative effect. The first factor consists in taking a +single page fault for each 2M virtual region touched by userland (so +reducing the enter/exit kernel frequency by a 512 times factor). This +only matters the first time the memory is accessed for the lifetime of +a memory mapping. The second long lasting and much more important +factor will affect all subsequent accesses to the memory for the whole +runtime of the application. The second factor consist of two +components: + +1) the TLB miss will run faster (especially with virtualization using + nested pagetables but almost always also on bare metal without + virtualization) + +2) a single TLB entry will be mapping a much larger amount of virtual + memory in turn reducing the number of TLB misses. With + virtualization and nested pagetables the TLB can be mapped of + larger size only if both KVM and the Linux guest are using + hugepages but a significant speedup already happens if only one of + the two is using hugepages just because of the fact the TLB miss is + going to run faster. + +THP can be enabled system wide or restricted to certain tasks or even +memory ranges inside task's address space. Unless THP is completely +disabled, there is ``khugepaged`` daemon that scans memory and +collapses sequences of basic pages into huge pages. + +The THP behaviour is controlled via :ref:`sysfs <thp_sysfs>` +interface and using madivse(2) and prctl(2) system calls. + +Transparent Hugepage Support maximizes the usefulness of free memory +if compared to the reservation approach of hugetlbfs by allowing all +unused memory to be used as cache or other movable (or even unmovable +entities). It doesn't require reservation to prevent hugepage +allocation failures to be noticeable from userland. It allows paging +and all other advanced VM features to be available on the +hugepages. It requires no modifications for applications to take +advantage of it. + +Applications however can be further optimized to take advantage of +this feature, like for example they've been optimized before to avoid +a flood of mmap system calls for every malloc(4k). Optimizing userland +is by far not mandatory and khugepaged already can take care of long +lived page allocations even for hugepage unaware applications that +deals with large amounts of memory. + +In certain cases when hugepages are enabled system wide, application +may end up allocating more memory resources. An application may mmap a +large region but only touch 1 byte of it, in that case a 2M page might +be allocated instead of a 4k page for no good. This is why it's +possible to disable hugepages system-wide and to only have them inside +MADV_HUGEPAGE madvise regions. + +Embedded systems should enable hugepages only inside madvise regions +to eliminate any risk of wasting any precious byte of memory and to +only run faster. + +Applications that gets a lot of benefit from hugepages and that don't +risk to lose memory by using hugepages, should use +madvise(MADV_HUGEPAGE) on their critical mmapped regions. + +.. _thp_sysfs: + +sysfs +===== + +Global THP controls +------------------- + +Transparent Hugepage Support for anonymous memory can be entirely disabled +(mostly for debugging purposes) or only enabled inside MADV_HUGEPAGE +regions (to avoid the risk of consuming more memory resources) or enabled +system wide. This can be achieved with one of:: + + echo always >/sys/kernel/mm/transparent_hugepage/enabled + echo madvise >/sys/kernel/mm/transparent_hugepage/enabled + echo never >/sys/kernel/mm/transparent_hugepage/enabled + +It's also possible to limit defrag efforts in the VM to generate +anonymous hugepages in case they're not immediately free to madvise +regions or to never try to defrag memory and simply fallback to regular +pages unless hugepages are immediately available. Clearly if we spend CPU +time to defrag memory, we would expect to gain even more by the fact we +use hugepages later instead of regular pages. This isn't always +guaranteed, but it may be more likely in case the allocation is for a +MADV_HUGEPAGE region. + +:: + + echo always >/sys/kernel/mm/transparent_hugepage/defrag + echo defer >/sys/kernel/mm/transparent_hugepage/defrag + echo defer+madvise >/sys/kernel/mm/transparent_hugepage/defrag + echo madvise >/sys/kernel/mm/transparent_hugepage/defrag + echo never >/sys/kernel/mm/transparent_hugepage/defrag + +always + means that an application requesting THP will stall on + allocation failure and directly reclaim pages and compact + memory in an effort to allocate a THP immediately. This may be + desirable for virtual machines that benefit heavily from THP + use and are willing to delay the VM start to utilise them. + +defer + means that an application will wake kswapd in the background + to reclaim pages and wake kcompactd to compact memory so that + THP is available in the near future. It's the responsibility + of khugepaged to then install the THP pages later. + +defer+madvise + will enter direct reclaim and compaction like ``always``, but + only for regions that have used madvise(MADV_HUGEPAGE); all + other regions will wake kswapd in the background to reclaim + pages and wake kcompactd to compact memory so that THP is + available in the near future. + +madvise + will enter direct reclaim like ``always`` but only for regions + that are have used madvise(MADV_HUGEPAGE). This is the default + behaviour. + +never + should be self-explanatory. + +By default kernel tries to use huge zero page on read page fault to +anonymous mapping. It's possible to disable huge zero page by writing 0 +or enable it back by writing 1:: + + echo 0 >/sys/kernel/mm/transparent_hugepage/use_zero_page + echo 1 >/sys/kernel/mm/transparent_hugepage/use_zero_page + +Some userspace (such as a test program, or an optimized memory allocation +library) may want to know the size (in bytes) of a transparent hugepage:: + + cat /sys/kernel/mm/transparent_hugepage/hpage_pmd_size + +khugepaged will be automatically started when +transparent_hugepage/enabled is set to "always" or "madvise, and it'll +be automatically shutdown if it's set to "never". + +Khugepaged controls +------------------- + +khugepaged runs usually at low frequency so while one may not want to +invoke defrag algorithms synchronously during the page faults, it +should be worth invoking defrag at least in khugepaged. However it's +also possible to disable defrag in khugepaged by writing 0 or enable +defrag in khugepaged by writing 1:: + + echo 0 >/sys/kernel/mm/transparent_hugepage/khugepaged/defrag + echo 1 >/sys/kernel/mm/transparent_hugepage/khugepaged/defrag + +You can also control how many pages khugepaged should scan at each +pass:: + + /sys/kernel/mm/transparent_hugepage/khugepaged/pages_to_scan + +and how many milliseconds to wait in khugepaged between each pass (you +can set this to 0 to run khugepaged at 100% utilization of one core):: + + /sys/kernel/mm/transparent_hugepage/khugepaged/scan_sleep_millisecs + +and how many milliseconds to wait in khugepaged if there's an hugepage +allocation failure to throttle the next allocation attempt:: + + /sys/kernel/mm/transparent_hugepage/khugepaged/alloc_sleep_millisecs + +The khugepaged progress can be seen in the number of pages collapsed:: + + /sys/kernel/mm/transparent_hugepage/khugepaged/pages_collapsed + +for each pass:: + + /sys/kernel/mm/transparent_hugepage/khugepaged/full_scans + +``max_ptes_none`` specifies how many extra small pages (that are +not already mapped) can be allocated when collapsing a group +of small pages into one large page:: + + /sys/kernel/mm/transparent_hugepage/khugepaged/max_ptes_none + +A higher value leads to use additional memory for programs. +A lower value leads to gain less thp performance. Value of +max_ptes_none can waste cpu time very little, you can +ignore it. + +``max_ptes_swap`` specifies how many pages can be brought in from +swap when collapsing a group of pages into a transparent huge page:: + + /sys/kernel/mm/transparent_hugepage/khugepaged/max_ptes_swap + +A higher value can cause excessive swap IO and waste +memory. A lower value can prevent THPs from being +collapsed, resulting fewer pages being collapsed into +THPs, and lower memory access performance. + +Boot parameter +============== + +You can change the sysfs boot time defaults of Transparent Hugepage +Support by passing the parameter ``transparent_hugepage=always`` or +``transparent_hugepage=madvise`` or ``transparent_hugepage=never`` +to the kernel command line. + +Hugepages in tmpfs/shmem +======================== + +You can control hugepage allocation policy in tmpfs with mount option +``huge=``. It can have following values: + +always + Attempt to allocate huge pages every time we need a new page; + +never + Do not allocate huge pages; + +within_size + Only allocate huge page if it will be fully within i_size. + Also respect fadvise()/madvise() hints; + +advise + Only allocate huge pages if requested with fadvise()/madvise(); + +The default policy is ``never``. + +``mount -o remount,huge= /mountpoint`` works fine after mount: remounting +``huge=never`` will not attempt to break up huge pages at all, just stop more +from being allocated. + +There's also sysfs knob to control hugepage allocation policy for internal +shmem mount: /sys/kernel/mm/transparent_hugepage/shmem_enabled. The mount +is used for SysV SHM, memfds, shared anonymous mmaps (of /dev/zero or +MAP_ANONYMOUS), GPU drivers' DRM objects, Ashmem. + +In addition to policies listed above, shmem_enabled allows two further +values: + +deny + For use in emergencies, to force the huge option off from + all mounts; +force + Force the huge option on for all - very useful for testing; + +Need of application restart +=========================== + +The transparent_hugepage/enabled values and tmpfs mount option only affect +future behavior. So to make them effective you need to restart any +application that could have been using hugepages. This also applies to the +regions registered in khugepaged. + +Monitoring usage +================ + +The number of anonymous transparent huge pages currently used by the +system is available by reading the AnonHugePages field in ``/proc/meminfo``. +To identify what applications are using anonymous transparent huge pages, +it is necessary to read ``/proc/PID/smaps`` and count the AnonHugePages fields +for each mapping. + +The number of file transparent huge pages mapped to userspace is available +by reading ShmemPmdMapped and ShmemHugePages fields in ``/proc/meminfo``. +To identify what applications are mapping file transparent huge pages, it +is necessary to read ``/proc/PID/smaps`` and count the FileHugeMapped fields +for each mapping. + +Note that reading the smaps file is expensive and reading it +frequently will incur overhead. + +There are a number of counters in ``/proc/vmstat`` that may be used to +monitor how successfully the system is providing huge pages for use. + +thp_fault_alloc + is incremented every time a huge page is successfully + allocated to handle a page fault. This applies to both the + first time a page is faulted and for COW faults. + +thp_collapse_alloc + is incremented by khugepaged when it has found + a range of pages to collapse into one huge page and has + successfully allocated a new huge page to store the data. + +thp_fault_fallback + is incremented if a page fault fails to allocate + a huge page and instead falls back to using small pages. + +thp_collapse_alloc_failed + is incremented if khugepaged found a range + of pages that should be collapsed into one huge page but failed + the allocation. + +thp_file_alloc + is incremented every time a file huge page is successfully + allocated. + +thp_file_mapped + is incremented every time a file huge page is mapped into + user address space. + +thp_split_page + is incremented every time a huge page is split into base + pages. This can happen for a variety of reasons but a common + reason is that a huge page is old and is being reclaimed. + This action implies splitting all PMD the page mapped with. + +thp_split_page_failed + is incremented if kernel fails to split huge + page. This can happen if the page was pinned by somebody. + +thp_deferred_split_page + is incremented when a huge page is put onto split + queue. This happens when a huge page is partially unmapped and + splitting it would free up some memory. Pages on split queue are + going to be split under memory pressure. + +thp_split_pmd + is incremented every time a PMD split into table of PTEs. + This can happen, for instance, when application calls mprotect() or + munmap() on part of huge page. It doesn't split huge page, only + page table entry. + +thp_zero_page_alloc + is incremented every time a huge zero page is + successfully allocated. It includes allocations which where + dropped due race with other allocation. Note, it doesn't count + every map of the huge zero page, only its allocation. + +thp_zero_page_alloc_failed + is incremented if kernel fails to allocate + huge zero page and falls back to using small pages. + +thp_swpout + is incremented every time a huge page is swapout in one + piece without splitting. + +thp_swpout_fallback + is incremented if a huge page has to be split before swapout. + Usually because failed to allocate some continuous swap space + for the huge page. + +As the system ages, allocating huge pages may be expensive as the +system uses memory compaction to copy data around memory to free a +huge page for use. There are some counters in ``/proc/vmstat`` to help +monitor this overhead. + +compact_stall + is incremented every time a process stalls to run + memory compaction so that a huge page is free for use. + +compact_success + is incremented if the system compacted memory and + freed a huge page for use. + +compact_fail + is incremented if the system tries to compact memory + but failed. + +compact_pages_moved + is incremented each time a page is moved. If + this value is increasing rapidly, it implies that the system + is copying a lot of data to satisfy the huge page allocation. + It is possible that the cost of copying exceeds any savings + from reduced TLB misses. + +compact_pagemigrate_failed + is incremented when the underlying mechanism + for moving a page failed. + +compact_blocks_moved + is incremented each time memory compaction examines + a huge page aligned range of pages. + +It is possible to establish how long the stalls were using the function +tracer to record how long was spent in __alloc_pages_nodemask and +using the mm_page_alloc tracepoint to identify which allocations were +for huge pages. + +Optimizing the applications +=========================== + +To be guaranteed that the kernel will map a 2M page immediately in any +memory region, the mmap region has to be hugepage naturally +aligned. posix_memalign() can provide that guarantee. + +Hugetlbfs +========= + +You can use hugetlbfs on a kernel that has transparent hugepage +support enabled just fine as always. No difference can be noted in +hugetlbfs other than there will be less overall fragmentation. All +usual features belonging to hugetlbfs are preserved and +unaffected. libhugetlbfs will also work fine as usual. diff --git a/Documentation/vm/userfaultfd.txt b/Documentation/admin-guide/mm/userfaultfd.rst index bb2f945f87ab..5048cf661a8a 100644 --- a/Documentation/vm/userfaultfd.txt +++ b/Documentation/admin-guide/mm/userfaultfd.rst @@ -1,6 +1,11 @@ -= Userfaultfd = +.. _userfaultfd: -== Objective == +=========== +Userfaultfd +=========== + +Objective +========= Userfaults allow the implementation of on-demand paging from userland and more generally they allow userland to take control of various @@ -9,7 +14,8 @@ memory page faults, something otherwise only the kernel code could do. For example userfaults allows a proper and more optimal implementation of the PROT_NONE+SIGSEGV trick. -== Design == +Design +====== Userfaults are delivered and resolved through the userfaultfd syscall. @@ -41,7 +47,8 @@ different processes without them being aware about what is going on themselves on the same region the manager is already tracking, which is a corner case that would currently return -EBUSY). -== API == +API +=== When first opened the userfaultfd must be enabled invoking the UFFDIO_API ioctl specifying a uffdio_api.api value set to UFFD_API (or @@ -101,7 +108,8 @@ UFFDIO_COPY. They're atomic as in guaranteeing that nothing can see an half copied page since it'll keep userfaulting until the copy has finished. -== QEMU/KVM == +QEMU/KVM +======== QEMU/KVM is using the userfaultfd syscall to implement postcopy live migration. Postcopy live migration is one form of memory @@ -163,7 +171,8 @@ sending the same page twice (in case the userfault is read by the postcopy thread just before UFFDIO_COPY|ZEROPAGE runs in the migration thread). -== Non-cooperative userfaultfd == +Non-cooperative userfaultfd +=========================== When the userfaultfd is monitored by an external manager, the manager must be able to track changes in the process virtual memory @@ -172,27 +181,30 @@ the same read(2) protocol as for the page fault notifications. The manager has to explicitly enable these events by setting appropriate bits in uffdio_api.features passed to UFFDIO_API ioctl: -UFFD_FEATURE_EVENT_FORK - enable userfaultfd hooks for fork(). When -this feature is enabled, the userfaultfd context of the parent process -is duplicated into the newly created process. The manager receives -UFFD_EVENT_FORK with file descriptor of the new userfaultfd context in -the uffd_msg.fork. - -UFFD_FEATURE_EVENT_REMAP - enable notifications about mremap() -calls. When the non-cooperative process moves a virtual memory area to -a different location, the manager will receive UFFD_EVENT_REMAP. The -uffd_msg.remap will contain the old and new addresses of the area and -its original length. - -UFFD_FEATURE_EVENT_REMOVE - enable notifications about -madvise(MADV_REMOVE) and madvise(MADV_DONTNEED) calls. The event -UFFD_EVENT_REMOVE will be generated upon these calls to madvise. The -uffd_msg.remove will contain start and end addresses of the removed -area. - -UFFD_FEATURE_EVENT_UNMAP - enable notifications about memory -unmapping. The manager will get UFFD_EVENT_UNMAP with uffd_msg.remove -containing start and end addresses of the unmapped area. +UFFD_FEATURE_EVENT_FORK + enable userfaultfd hooks for fork(). When this feature is + enabled, the userfaultfd context of the parent process is + duplicated into the newly created process. The manager + receives UFFD_EVENT_FORK with file descriptor of the new + userfaultfd context in the uffd_msg.fork. + +UFFD_FEATURE_EVENT_REMAP + enable notifications about mremap() calls. When the + non-cooperative process moves a virtual memory area to a + different location, the manager will receive + UFFD_EVENT_REMAP. The uffd_msg.remap will contain the old and + new addresses of the area and its original length. + +UFFD_FEATURE_EVENT_REMOVE + enable notifications about madvise(MADV_REMOVE) and + madvise(MADV_DONTNEED) calls. The event UFFD_EVENT_REMOVE will + be generated upon these calls to madvise. The uffd_msg.remove + will contain start and end addresses of the removed area. + +UFFD_FEATURE_EVENT_UNMAP + enable notifications about memory unmapping. The manager will + get UFFD_EVENT_UNMAP with uffd_msg.remove containing start and + end addresses of the unmapped area. Although the UFFD_FEATURE_EVENT_REMOVE and UFFD_FEATURE_EVENT_UNMAP are pretty similar, they quite differ in the action expected from the diff --git a/Documentation/admin-guide/pm/intel_pstate.rst b/Documentation/admin-guide/pm/intel_pstate.rst index d2b6fda3d67b..ab2fe0eda1d7 100644 --- a/Documentation/admin-guide/pm/intel_pstate.rst +++ b/Documentation/admin-guide/pm/intel_pstate.rst @@ -145,7 +145,7 @@ feature enabled.] In this mode ``intel_pstate`` registers utilization update callbacks with the CPU scheduler in order to run a P-state selection algorithm, either -``powersave`` or ``performance``, depending on the ``scaling_cur_freq`` policy +``powersave`` or ``performance``, depending on the ``scaling_governor`` policy setting in ``sysfs``. The current CPU frequency information to be made available from the ``scaling_cur_freq`` policy attribute in ``sysfs`` is periodically updated by those utilization update callbacks too. diff --git a/Documentation/admin-guide/pm/sleep-states.rst b/Documentation/admin-guide/pm/sleep-states.rst index 1e5c0f00cb2f..dbf5acd49f35 100644 --- a/Documentation/admin-guide/pm/sleep-states.rst +++ b/Documentation/admin-guide/pm/sleep-states.rst @@ -15,7 +15,7 @@ Sleep States That Can Be Supported ================================== Depending on its configuration and the capabilities of the platform it runs on, -the Linux kernel can support up to four system sleep states, includig +the Linux kernel can support up to four system sleep states, including hibernation and up to three variants of system suspend. The sleep states that can be supported by the kernel are listed below. diff --git a/Documentation/admin-guide/ramoops.rst b/Documentation/admin-guide/ramoops.rst index 4efd7ce77565..6dbcc5481000 100644 --- a/Documentation/admin-guide/ramoops.rst +++ b/Documentation/admin-guide/ramoops.rst @@ -61,7 +61,7 @@ Setting the ramoops parameters can be done in several different manners: mem=128M ramoops.mem_address=0x8000000 ramoops.ecc=1 B. Use Device Tree bindings, as described in - ``Documentation/device-tree/bindings/reserved-memory/admin-guide/ramoops.rst``. + ``Documentation/devicetree/bindings/reserved-memory/ramoops.txt``. For example:: reserved-memory { diff --git a/Documentation/arm/Marvell/README b/Documentation/arm/Marvell/README index b5bb7f518840..56ada27c53be 100644 --- a/Documentation/arm/Marvell/README +++ b/Documentation/arm/Marvell/README @@ -302,19 +302,15 @@ Berlin family (Multimedia Solutions) 88DE3010, Armada 1000 (no Linux support) Core: Marvell PJ1 (ARMv5TE), Dual-core Product Brief: http://www.marvell.com.cn/digital-entertainment/assets/armada_1000_pb.pdf - 88DE3005, Armada 1500-mini 88DE3005, Armada 1500 Mini Design name: BG2CD Core: ARM Cortex-A9, PL310 L2CC - Homepage: http://www.marvell.com/multimedia-solutions/armada-1500-mini/ - 88DE3006, Armada 1500 Mini Plus - Design name: BG2CDP - Core: Dual Core ARM Cortex-A7 - Homepage: http://www.marvell.com/multimedia-solutions/armada-1500-mini-plus/ + 88DE3006, Armada 1500 Mini Plus + Design name: BG2CDP + Core: Dual Core ARM Cortex-A7 88DE3100, Armada 1500 Design name: BG2 Core: Marvell PJ4B-MP (ARMv7), Tauros3 L2CC - Product Brief: http://www.marvell.com/digital-entertainment/armada-1500/assets/Marvell-ARMADA-1500-Product-Brief.pdf 88DE3114, Armada 1500 Pro Design name: BG2Q Core: Quad Core ARM Cortex-A9, PL310 L2CC @@ -324,13 +320,16 @@ Berlin family (Multimedia Solutions) 88DE3218, ARMADA 1500 Ultra Core: ARM Cortex-A53 - Homepage: http://www.marvell.com/multimedia-solutions/ + Homepage: https://www.synaptics.com/products/multimedia-solutions Directory: arch/arm/mach-berlin Comments: + * This line of SoCs is based on Marvell Sheeva or ARM Cortex CPUs with Synopsys DesignWare (IRQ, GPIO, Timers, ...) and PXA IP (SDHCI, USB, ETH, ...). + * The Berlin family was acquired by Synaptics from Marvell in 2017. + CPU Cores --------- diff --git a/Documentation/arm/Atmel/README b/Documentation/arm/Microchip/README index afb13c15389d..a366f37d38f1 100644 --- a/Documentation/arm/Atmel/README +++ b/Documentation/arm/Microchip/README @@ -1,54 +1,54 @@ -ARM Atmel SoCs (aka AT91) -========================= +ARM Microchip SoCs (aka AT91) +============================= Introduction ------------ -This document gives useful information about the ARM Atmel SoCs that are +This document gives useful information about the ARM Microchip SoCs that are currently supported in Linux Mainline (you know, the one on kernel.org). -It is important to note that the Atmel | SMART ARM-based MPU product line is -historically named "AT91" or "at91" throughout the Linux kernel development -process even if this product prefix has completely disappeared from the -official Atmel product name. Anyway, files, directories, git trees, +It is important to note that the Microchip (previously Atmel) ARM-based MPU +product line is historically named "AT91" or "at91" throughout the Linux kernel +development process even if this product prefix has completely disappeared from +the official Microchip product name. Anyway, files, directories, git trees, git branches/tags and email subject always contain this "at91" sub-string. AT91 SoCs --------- Documentation and detailed datasheet for each product are available on -the Atmel website: http://www.atmel.com. +the Microchip website: http://www.microchip.com. Flavors: * ARM 920 based SoC - at91rm9200 + Datasheet - http://www.atmel.com/Images/doc1768.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-1768-32-bit-ARM920T-Embedded-Microprocessor-AT91RM9200_Datasheet.pdf * ARM 926 based SoCs - at91sam9260 + Datasheet - http://www.atmel.com/Images/doc6221.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-6221-32-bit-ARM926EJ-S-Embedded-Microprocessor-SAM9260_Datasheet.pdf - at91sam9xe + Datasheet - http://www.atmel.com/Images/Atmel-6254-32-bit-ARM926EJ-S-Embedded-Microprocessor-SAM9XE_Datasheet.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-6254-32-bit-ARM926EJ-S-Embedded-Microprocessor-SAM9XE_Datasheet.pdf - at91sam9261 + Datasheet - http://www.atmel.com/Images/doc6062.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-6062-ARM926EJ-S-Microprocessor-SAM9261_Datasheet.pdf - at91sam9263 + Datasheet - http://www.atmel.com/Images/Atmel_6249_32-bit-ARM926EJ-S-Microcontroller_SAM9263_Datasheet.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-6249-32-bit-ARM926EJ-S-Embedded-Microprocessor-SAM9263_Datasheet.pdf - at91sam9rl + Datasheet - http://www.atmel.com/Images/doc6289.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/doc6289.pdf - at91sam9g20 + Datasheet - http://www.atmel.com/Images/doc6384.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/DS60001516A.pdf - at91sam9g45 family - at91sam9g45 @@ -56,7 +56,7 @@ the Atmel website: http://www.atmel.com. - at91sam9m10 - at91sam9m11 (device superset) + Datasheet - http://www.atmel.com/Images/Atmel-6437-32-bit-ARM926-Embedded-Microprocessor-SAM9M11_Datasheet.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-6437-32-bit-ARM926-Embedded-Microprocessor-SAM9M11_Datasheet.pdf - at91sam9x5 family (aka "The 5 series") - at91sam9g15 @@ -65,11 +65,11 @@ the Atmel website: http://www.atmel.com. - at91sam9x25 - at91sam9x35 + Datasheet (can be considered as covering the whole family) - http://www.atmel.com/Images/Atmel_11055_32-bit-ARM926EJ-S-Microcontroller_SAM9X35_Datasheet.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-11055-32-bit-ARM926EJ-S-Microcontroller-SAM9X35_Datasheet.pdf - at91sam9n12 + Datasheet - http://www.atmel.com/Images/Atmel_11063_32-bit-ARM926EJ-S-Microcontroller_SAM9N12CN11CN12_Datasheet.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/DS60001517A.pdf * ARM Cortex-A5 based SoCs - sama5d3 family @@ -79,7 +79,7 @@ the Atmel website: http://www.atmel.com. - sama5d35 - sama5d36 (device superset) + Datasheet - http://www.atmel.com/Images/Atmel-11121-32-bit-Cortex-A5-Microcontroller-SAMA5D3_Datasheet.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-11121-32-bit-Cortex-A5-Microcontroller-SAMA5D3_Datasheet.pdf * ARM Cortex-A5 + NEON based SoCs - sama5d4 family @@ -88,7 +88,7 @@ the Atmel website: http://www.atmel.com. - sama5d43 - sama5d44 (device superset) + Datasheet - http://www.atmel.com/Images/Atmel-11238-32-bit-Cortex-A5-Microcontroller-SAMA5D4_Datasheet.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/60001525A.pdf - sama5d2 family - sama5d21 @@ -99,7 +99,7 @@ the Atmel website: http://www.atmel.com. - sama5d27 (device superset) - sama5d28 (device superset + environmental monitors) + Datasheet - http://www.atmel.com/Images/Atmel-11267-32-bit-Cortex-A5-Microcontroller-SAMA5D2_Datasheet.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/DS60001476B.pdf * ARM Cortex-M7 MCUs - sams70 family @@ -112,8 +112,6 @@ the Atmel website: http://www.atmel.com. - sams70q19 - sams70q20 - sams70q21 - + Datasheet - http://www.atmel.com/Images/Atmel-11242-32-bit-Cortex-M7-Microcontroller-SAM-S70Q-SAM-S70N-SAM-S70J_Datasheet.pdf - samv70 family - samv70j19 @@ -122,8 +120,6 @@ the Atmel website: http://www.atmel.com. - samv70n20 - samv70q19 - samv70q20 - + Datasheet - http://www.atmel.com/Images/Atmel-11297-32-bit-Cortex-M7-Microcontroller-SAM-V70Q-SAM-V70N-SAM-V70J_Datasheet.pdf - samv71 family - samv71j19 @@ -135,13 +131,15 @@ the Atmel website: http://www.atmel.com. - samv71q19 - samv71q20 - samv71q21 + + Datasheet - http://www.atmel.com/Images/Atmel-44003-32-bit-Cortex-M7-Microcontroller-SAM-V71Q-SAM-V71N-SAM-V71J_Datasheet.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/60001527A.pdf + Linux kernel information ------------------------ Linux kernel mach directory: arch/arm/mach-at91 -MAINTAINERS entry is: "ARM/ATMEL AT91RM9200 AND AT91SAM ARM ARCHITECTURES" +MAINTAINERS entry is: "ARM/Microchip (AT91) SoC support" Device Tree for AT91 SoCs and boards diff --git a/Documentation/arm/Samsung-S3C24XX/S3C2412.txt b/Documentation/arm/Samsung-S3C24XX/S3C2412.txt index f057876b920b..dc1fd362d3c1 100644 --- a/Documentation/arm/Samsung-S3C24XX/S3C2412.txt +++ b/Documentation/arm/Samsung-S3C24XX/S3C2412.txt @@ -46,7 +46,7 @@ NAND ---- The NAND hardware is similar to the S3C2440, and is supported by the - s3c2410 driver in the drivers/mtd/nand directory. + s3c2410 driver in the drivers/mtd/nand/raw directory. USB Host diff --git a/Documentation/arm/stm32/overview.rst b/Documentation/arm/stm32/overview.rst new file mode 100644 index 000000000000..85cfc8410798 --- /dev/null +++ b/Documentation/arm/stm32/overview.rst @@ -0,0 +1,34 @@ +======================== +STM32 ARM Linux Overview +======================== + +Introduction +------------ + +The STMicroelectronics STM32 family of Cortex-A microprocessors (MPUs) and +Cortex-M microcontrollers (MCUs) are supported by the 'STM32' platform of +ARM Linux. + +Configuration +------------- + +For MCUs, use the provided default configuration: + make stm32_defconfig +For MPUs, use multi_v7 configuration: + make multi_v7_defconfig + +Layout +------ + +All the files for multiple machine families are located in the platform code +contained in arch/arm/mach-stm32 + +There is a generic board board-dt.c in the mach folder which support +Flattened Device Tree, which means, it works with any compatible board with +Device Trees. + +:Authors: + +- Maxime Coquelin <mcoquelin.stm32@gmail.com> +- Ludovic Barre <ludovic.barre@st.com> +- Gerald Baeza <gerald.baeza@st.com> diff --git a/Documentation/arm/stm32/overview.txt b/Documentation/arm/stm32/overview.txt deleted file mode 100644 index a03b0357c017..000000000000 --- a/Documentation/arm/stm32/overview.txt +++ /dev/null @@ -1,33 +0,0 @@ - STM32 ARM Linux Overview - ======================== - -Introduction ------------- - - The STMicroelectronics family of Cortex-M based MCUs are supported by the - 'STM32' platform of ARM Linux. Currently only the STM32F429 (Cortex-M4) - and STM32F746 (Cortex-M7) are supported. - - -Configuration -------------- - - A generic configuration is provided for STM32 family, and can be used as the - default by - make stm32_defconfig - -Layout ------- - - All the files for multiple machine families are located in the platform code - contained in arch/arm/mach-stm32 - - There is a generic board board-dt.c in the mach folder which support - Flattened Device Tree, which means, it works with any compatible board with - Device Trees. - - -Document Author ---------------- - - Maxime Coquelin <mcoquelin.stm32@gmail.com> diff --git a/Documentation/arm/stm32/stm32f429-overview.rst b/Documentation/arm/stm32/stm32f429-overview.rst new file mode 100644 index 000000000000..18feda97f483 --- /dev/null +++ b/Documentation/arm/stm32/stm32f429-overview.rst @@ -0,0 +1,26 @@ +STM32F429 Overview +================== + +Introduction +------------ + +The STM32F429 is a Cortex-M4 MCU aimed at various applications. +It features: + +- ARM Cortex-M4 up to 180MHz with FPU +- 2MB internal Flash Memory +- External memory support through FMC controller (PSRAM, SDRAM, NOR, NAND) +- I2C, SPI, SAI, CAN, USB OTG, Ethernet controllers +- LCD controller & Camera interface +- Cryptographic processor + +Resources +--------- + +Datasheet and reference manual are publicly available on ST website (STM32F429_). + +.. _STM32F429: http://www.st.com/web/en/catalog/mmc/FM141/SC1169/SS1577/LN1806?ecmp=stm32f429-439_pron_pr-ces2014_nov2013 + +:Authors: + +Maxime Coquelin <mcoquelin.stm32@gmail.com> diff --git a/Documentation/arm/stm32/stm32f429-overview.txt b/Documentation/arm/stm32/stm32f429-overview.txt deleted file mode 100644 index 5206822bd8ef..000000000000 --- a/Documentation/arm/stm32/stm32f429-overview.txt +++ /dev/null @@ -1,22 +0,0 @@ - STM32F429 Overview - ================== - - Introduction - ------------ - The STM32F429 is a Cortex-M4 MCU aimed at various applications. - It features: - - ARM Cortex-M4 up to 180MHz with FPU - - 2MB internal Flash Memory - - External memory support through FMC controller (PSRAM, SDRAM, NOR, NAND) - - I2C, SPI, SAI, CAN, USB OTG, Ethernet controllers - - LCD controller & Camera interface - - Cryptographic processor - - Resources - --------- - Datasheet and reference manual are publicly available on ST website: - - http://www.st.com/web/en/catalog/mmc/FM141/SC1169/SS1577/LN1806?ecmp=stm32f429-439_pron_pr-ces2014_nov2013 - - Document Author - --------------- - Maxime Coquelin <mcoquelin.stm32@gmail.com> diff --git a/Documentation/arm/stm32/stm32f746-overview.rst b/Documentation/arm/stm32/stm32f746-overview.rst new file mode 100644 index 000000000000..b5f4b6ce7656 --- /dev/null +++ b/Documentation/arm/stm32/stm32f746-overview.rst @@ -0,0 +1,33 @@ +STM32F746 Overview +================== + +Introduction +------------ + +The STM32F746 is a Cortex-M7 MCU aimed at various applications. +It features: + +- Cortex-M7 core running up to @216MHz +- 1MB internal flash, 320KBytes internal RAM (+4KB of backup SRAM) +- FMC controller to connect SDRAM, NOR and NAND memories +- Dual mode QSPI +- SD/MMC/SDIO support +- Ethernet controller +- USB OTFG FS & HS controllers +- I2C, SPI, CAN busses support +- Several 16 & 32 bits general purpose timers +- Serial Audio interface +- LCD controller +- HDMI-CEC +- SPDIFRX + +Resources +--------- + +Datasheet and reference manual are publicly available on ST website (STM32F746_). + +.. _STM32F746: http://www.st.com/content/st_com/en/products/microcontrollers/stm32-32-bit-arm-cortex-mcus/stm32f7-series/stm32f7x6/stm32f746ng.html + +:Authors: + +Alexandre Torgue <alexandre.torgue@st.com> diff --git a/Documentation/arm/stm32/stm32f746-overview.txt b/Documentation/arm/stm32/stm32f746-overview.txt deleted file mode 100644 index cffd2b1ccd6f..000000000000 --- a/Documentation/arm/stm32/stm32f746-overview.txt +++ /dev/null @@ -1,34 +0,0 @@ - STM32F746 Overview - ================== - - Introduction - ------------ - The STM32F746 is a Cortex-M7 MCU aimed at various applications. - It features: - - Cortex-M7 core running up to @216MHz - - 1MB internal flash, 320KBytes internal RAM (+4KB of backup SRAM) - - FMC controller to connect SDRAM, NOR and NAND memories - - Dual mode QSPI - - SD/MMC/SDIO support - - Ethernet controller - - USB OTFG FS & HS controllers - - I2C, SPI, CAN busses support - - Several 16 & 32 bits general purpose timers - - Serial Audio interface - - LCD controller - - HDMI-CEC - - SPDIFRX - - Resources - --------- - Datasheet and reference manual are publicly available on ST website: - - http://www.st.com/content/st_com/en/products/microcontrollers/stm32-32-bit-arm-cortex-mcus/stm32f7-series/stm32f7x6/stm32f746ng.html - - Document Author - --------------- - Alexandre Torgue <alexandre.torgue@st.com> - - - - - diff --git a/Documentation/arm/stm32/stm32f769-overview.rst b/Documentation/arm/stm32/stm32f769-overview.rst new file mode 100644 index 000000000000..228656ced2fe --- /dev/null +++ b/Documentation/arm/stm32/stm32f769-overview.rst @@ -0,0 +1,35 @@ +STM32F769 Overview +================== + +Introduction +------------ + +The STM32F769 is a Cortex-M7 MCU aimed at various applications. +It features: + +- Cortex-M7 core running up to @216MHz +- 2MB internal flash, 512KBytes internal RAM (+4KB of backup SRAM) +- FMC controller to connect SDRAM, NOR and NAND memories +- Dual mode QSPI +- SD/MMC/SDIO support*2 +- Ethernet controller +- USB OTFG FS & HS controllers +- I2C*4, SPI*6, CAN*3 busses support +- Several 16 & 32 bits general purpose timers +- Serial Audio interface*2 +- LCD controller +- HDMI-CEC +- DSI +- SPDIFRX +- MDIO salave interface + +Resources +--------- + +Datasheet and reference manual are publicly available on ST website (STM32F769_). + +.. _STM32F769: http://www.st.com/content/st_com/en/products/microcontrollers/stm32-32-bit-arm-cortex-mcus/stm32-high-performance-mcus/stm32f7-series/stm32f7x9/stm32f769ni.html + +:Authors: + +Alexandre Torgue <alexandre.torgue@st.com> diff --git a/Documentation/arm/stm32/stm32h743-overview.rst b/Documentation/arm/stm32/stm32h743-overview.rst new file mode 100644 index 000000000000..3458dc00095d --- /dev/null +++ b/Documentation/arm/stm32/stm32h743-overview.rst @@ -0,0 +1,34 @@ +STM32H743 Overview +================== + +Introduction +------------ + +The STM32H743 is a Cortex-M7 MCU aimed at various applications. +It features: + +- Cortex-M7 core running up to @400MHz +- 2MB internal flash, 1MBytes internal RAM +- FMC controller to connect SDRAM, NOR and NAND memories +- Dual mode QSPI +- SD/MMC/SDIO support +- Ethernet controller +- USB OTFG FS & HS controllers +- I2C, SPI, CAN busses support +- Several 16 & 32 bits general purpose timers +- Serial Audio interface +- LCD controller +- HDMI-CEC +- SPDIFRX +- DFSDM + +Resources +--------- + +Datasheet and reference manual are publicly available on ST website (STM32H743_). + +.. _STM32H743: http://www.st.com/en/microcontrollers/stm32h7x3.html?querycriteria=productId=LN2033 + +:Authors: + +Alexandre Torgue <alexandre.torgue@st.com> diff --git a/Documentation/arm/stm32/stm32h743-overview.txt b/Documentation/arm/stm32/stm32h743-overview.txt deleted file mode 100644 index 3031cbae31a5..000000000000 --- a/Documentation/arm/stm32/stm32h743-overview.txt +++ /dev/null @@ -1,30 +0,0 @@ - STM32H743 Overview - ================== - - Introduction - ------------ - The STM32H743 is a Cortex-M7 MCU aimed at various applications. - It features: - - Cortex-M7 core running up to @400MHz - - 2MB internal flash, 1MBytes internal RAM - - FMC controller to connect SDRAM, NOR and NAND memories - - Dual mode QSPI - - SD/MMC/SDIO support - - Ethernet controller - - USB OTFG FS & HS controllers - - I2C, SPI, CAN busses support - - Several 16 & 32 bits general purpose timers - - Serial Audio interface - - LCD controller - - HDMI-CEC - - SPDIFRX - - DFSDM - - Resources - --------- - Datasheet and reference manual are publicly available on ST website: - - http://www.st.com/en/microcontrollers/stm32h7x3.html?querycriteria=productId=LN2033 - - Document Author - --------------- - Alexandre Torgue <alexandre.torgue@st.com> diff --git a/Documentation/arm/stm32/stm32mp157-overview.rst b/Documentation/arm/stm32/stm32mp157-overview.rst new file mode 100644 index 000000000000..62e176d47ca7 --- /dev/null +++ b/Documentation/arm/stm32/stm32mp157-overview.rst @@ -0,0 +1,19 @@ +STM32MP157 Overview +=================== + +Introduction +------------ + +The STM32MP157 is a Cortex-A MPU aimed at various applications. +It features: + +- Dual core Cortex-A7 application core +- 2D/3D image composition with GPU +- Standard memories interface support +- Standard connectivity, widely inherited from the STM32 MCU family +- Comprehensive security support + +:Authors: + +- Ludovic Barre <ludovic.barre@st.com> +- Gerald Baeza <gerald.baeza@st.com> diff --git a/Documentation/arm64/memory.txt b/Documentation/arm64/memory.txt index 671bc0639262..c5dab30d3389 100644 --- a/Documentation/arm64/memory.txt +++ b/Documentation/arm64/memory.txt @@ -86,9 +86,12 @@ Translation table lookup with 64KB pages: +-------------------------------------------------> [63] TTBR0/1 -When using KVM without the Virtualization Host Extensions, the hypervisor -maps kernel pages in EL2 at a fixed offset from the kernel VA. See the -kern_hyp_va macro for more details. +When using KVM without the Virtualization Host Extensions, the +hypervisor maps kernel pages in EL2 at a fixed (and potentially +random) offset from the linear mapping. See the kern_hyp_va macro and +kvm_update_va_mask function for more details. MMIO devices such as +GICv2 gets mapped next to the HYP idmap page, as do vectors when +ARM64_HARDEN_EL2_VECTORS is selected for particular CPUs. When using KVM with the Virtualization Host Extensions, no additional mappings are created, since the host kernel runs directly in EL2. diff --git a/Documentation/block/cmdline-partition.txt b/Documentation/block/cmdline-partition.txt index 525b9f6d7fb4..760a3f7c3ed4 100644 --- a/Documentation/block/cmdline-partition.txt +++ b/Documentation/block/cmdline-partition.txt @@ -1,7 +1,9 @@ Embedded device command line partition parsing ===================================================================== -Support for reading the block device partition table from the command line. +The "blkdevparts" command line option adds support for reading the +block device partition table from the kernel command line. + It is typically used for fixed block (eMMC) embedded devices. It has no MBR, so saves storage space. Bootloader can be easily accessed by absolute address of data on the block device. @@ -14,22 +16,27 @@ blkdevparts=<blkdev-def>[;<blkdev-def>] <partdef> := <size>[@<offset>](part-name) <blkdev-id> - block device disk name, embedded device used fixed block device, - it's disk name also fixed. such as: mmcblk0, mmcblk1, mmcblk0boot0. + block device disk name. Embedded device uses fixed block device. + Its disk name is also fixed, such as: mmcblk0, mmcblk1, mmcblk0boot0. <size> partition size, in bytes, such as: 512, 1m, 1G. + size may contain an optional suffix of (upper or lower case): + K, M, G, T, P, E. + "-" is used to denote all remaining space. <offset> partition start address, in bytes. + offset may contain an optional suffix of (upper or lower case): + K, M, G, T, P, E. (part-name) - partition name, kernel send uevent with "PARTNAME". application can create - a link to block device partition with the name "PARTNAME". - user space application can access partition by partition name. + partition name. Kernel sends uevent with "PARTNAME". Application can + create a link to block device partition with the name "PARTNAME". + User space application can access partition by partition name. Example: - eMMC disk name is "mmcblk0" and "mmcblk0boot0" + eMMC disk names are "mmcblk0" and "mmcblk0boot0". bootargs: 'blkdevparts=mmcblk0:1G(data0),1G(data1),-;mmcblk0boot0:1m(boot),-(kernel)' diff --git a/Documentation/block/null_blk.txt b/Documentation/block/null_blk.txt index 733927a7b501..07f147381f32 100644 --- a/Documentation/block/null_blk.txt +++ b/Documentation/block/null_blk.txt @@ -71,13 +71,16 @@ use_per_node_hctx=[0/1]: Default: 0 1: The multi-queue block layer is instantiated with a hardware dispatch queue for each CPU node in the system. -use_lightnvm=[0/1]: Default: 0 - Register device with LightNVM. Requires blk-mq and CONFIG_NVM to be enabled. - no_sched=[0/1]: Default: 0 0: nullb* use default blk-mq io scheduler. 1: nullb* doesn't use io scheduler. +blocking=[0/1]: Default: 0 + 0: Register as a non-blocking blk-mq driver device. + 1: Register as a blocking blk-mq driver device, null_blk will set + the BLK_MQ_F_BLOCKING flag, indicating that it sometimes/always + needs to block in its ->queue_rq() function. + shared_tags=[0/1]: Default: 0 0: Tag set is not shared. 1: Tag set shared between devices for blk-mq. Only makes sense with diff --git a/Documentation/bpf/bpf_devel_QA.txt b/Documentation/bpf/bpf_devel_QA.txt index 1a0b704e1a38..da57601153a0 100644 --- a/Documentation/bpf/bpf_devel_QA.txt +++ b/Documentation/bpf/bpf_devel_QA.txt @@ -557,6 +557,14 @@ A: Although LLVM IR generation and optimization try to stay architecture pulls in some header files containing file scope host assembly codes. - You can add "-fno-jump-tables" to work around the switch table issue. - Otherwise, you can use bpf target. + Otherwise, you can use bpf target. Additionally, you _must_ use bpf target + when: + + - Your program uses data structures with pointer or long / unsigned long + types that interface with BPF helpers or context data structures. Access + into these structures is verified by the BPF verifier and may result + in verification failures if the native architecture is not aligned with + the BPF architecture, e.g. 64-bit. An example of this is + BPF_PROG_TYPE_SK_MSG require '-target bpf' Happy BPF hacking! diff --git a/Documentation/cgroup-v1/memory.txt b/Documentation/cgroup-v1/memory.txt index a4af2e124e24..3682e99234c2 100644 --- a/Documentation/cgroup-v1/memory.txt +++ b/Documentation/cgroup-v1/memory.txt @@ -262,7 +262,7 @@ When oom event notifier is registered, event will be delivered. 2.6 Locking lock_page_cgroup()/unlock_page_cgroup() should not be called under - mapping->tree_lock. + the i_pages lock. Other lock order is following: PG_locked. diff --git a/Documentation/core-api/atomic_ops.rst b/Documentation/core-api/atomic_ops.rst index fce929144ccd..2e7165f86f55 100644 --- a/Documentation/core-api/atomic_ops.rst +++ b/Documentation/core-api/atomic_ops.rst @@ -111,7 +111,6 @@ If the compiler can prove that do_something() does not store to the variable a, then the compiler is within its rights transforming this to the following:: - tmp = a; if (a > 0) for (;;) do_something(); @@ -119,7 +118,7 @@ the following:: If you don't want the compiler to do this (and you probably don't), then you should use something like the following:: - while (READ_ONCE(a) < 0) + while (READ_ONCE(a) > 0) do_something(); Alternatively, you could place a barrier() call in the loop. @@ -467,10 +466,12 @@ Like the above, except that these routines return a boolean which indicates whether the changed bit was set _BEFORE_ the atomic bit operation. -WARNING! It is incredibly important that the value be a boolean, -ie. "0" or "1". Do not try to be fancy and save a few instructions by -declaring the above to return "long" and just returning something like -"old_val & mask" because that will not work. + +.. warning:: + It is incredibly important that the value be a boolean, ie. "0" or "1". + Do not try to be fancy and save a few instructions by declaring the + above to return "long" and just returning something like "old_val & + mask" because that will not work. For one thing, this return value gets truncated to int in many code paths using these interfaces, so on 64-bit if the bit is set in the diff --git a/Documentation/cachetlb.txt b/Documentation/core-api/cachetlb.rst index 6eb9d3f090cd..6eb9d3f090cd 100644 --- a/Documentation/cachetlb.txt +++ b/Documentation/core-api/cachetlb.rst diff --git a/Documentation/circular-buffers.txt b/Documentation/core-api/circular-buffers.rst index 53e51caa3347..53e51caa3347 100644 --- a/Documentation/circular-buffers.txt +++ b/Documentation/core-api/circular-buffers.rst diff --git a/Documentation/core-api/gfp_mask-from-fs-io.rst b/Documentation/core-api/gfp_mask-from-fs-io.rst new file mode 100644 index 000000000000..e0df8f416582 --- /dev/null +++ b/Documentation/core-api/gfp_mask-from-fs-io.rst @@ -0,0 +1,66 @@ +================================= +GFP masks used from FS/IO context +================================= + +:Date: May, 2018 +:Author: Michal Hocko <mhocko@kernel.org> + +Introduction +============ + +Code paths in the filesystem and IO stacks must be careful when +allocating memory to prevent recursion deadlocks caused by direct +memory reclaim calling back into the FS or IO paths and blocking on +already held resources (e.g. locks - most commonly those used for the +transaction context). + +The traditional way to avoid this deadlock problem is to clear __GFP_FS +respectively __GFP_IO (note the latter implies clearing the first as well) in +the gfp mask when calling an allocator. GFP_NOFS respectively GFP_NOIO can be +used as shortcut. It turned out though that above approach has led to +abuses when the restricted gfp mask is used "just in case" without a +deeper consideration which leads to problems because an excessive use +of GFP_NOFS/GFP_NOIO can lead to memory over-reclaim or other memory +reclaim issues. + +New API +======== + +Since 4.12 we do have a generic scope API for both NOFS and NOIO context +``memalloc_nofs_save``, ``memalloc_nofs_restore`` respectively ``memalloc_noio_save``, +``memalloc_noio_restore`` which allow to mark a scope to be a critical +section from a filesystem or I/O point of view. Any allocation from that +scope will inherently drop __GFP_FS respectively __GFP_IO from the given +mask so no memory allocation can recurse back in the FS/IO. + +.. kernel-doc:: include/linux/sched/mm.h + :functions: memalloc_nofs_save memalloc_nofs_restore +.. kernel-doc:: include/linux/sched/mm.h + :functions: memalloc_noio_save memalloc_noio_restore + +FS/IO code then simply calls the appropriate save function before +any critical section with respect to the reclaim is started - e.g. +lock shared with the reclaim context or when a transaction context +nesting would be possible via reclaim. The restore function should be +called when the critical section ends. All that ideally along with an +explanation what is the reclaim context for easier maintenance. + +Please note that the proper pairing of save/restore functions +allows nesting so it is safe to call ``memalloc_noio_save`` or +``memalloc_noio_restore`` respectively from an existing NOIO or NOFS +scope. + +What about __vmalloc(GFP_NOFS) +============================== + +vmalloc doesn't support GFP_NOFS semantic because there are hardcoded +GFP_KERNEL allocations deep inside the allocator which are quite non-trivial +to fix up. That means that calling ``vmalloc`` with GFP_NOFS/GFP_NOIO is +almost always a bug. The good news is that the NOFS/NOIO semantic can be +achieved by the scope API. + +In the ideal world, upper layers should already mark dangerous contexts +and so no special care is required and vmalloc should be called without +any problems. Sometimes if the context is not really clear or there are +layering violations then the recommended way around that is to wrap ``vmalloc`` +by the scope API with a comment explaining the problem. diff --git a/Documentation/core-api/index.rst b/Documentation/core-api/index.rst index c670a8031786..f5a66b72f984 100644 --- a/Documentation/core-api/index.rst +++ b/Documentation/core-api/index.rst @@ -14,6 +14,7 @@ Core utilities kernel-api assoc_array atomic_ops + cachetlb refcount-vs-atomic cpu_hotplug idr @@ -25,6 +26,8 @@ Core utilities genalloc errseq printk-formats + circular-buffers + gfp_mask-from-fs-io Interfaces for kernel debugging =============================== diff --git a/Documentation/core-api/kernel-api.rst b/Documentation/core-api/kernel-api.rst index ff335f8aeb39..8e44aea366c2 100644 --- a/Documentation/core-api/kernel-api.rst +++ b/Documentation/core-api/kernel-api.rst @@ -39,17 +39,17 @@ String Manipulation .. kernel-doc:: lib/string.c :export: +Basic Kernel Library Functions +============================== + +The Linux kernel provides more basic utility functions. + Bit Operations -------------- .. kernel-doc:: arch/x86/include/asm/bitops.h :internal: -Basic Kernel Library Functions -============================== - -The Linux kernel provides more basic utility functions. - Bitmap Operations ----------------- @@ -80,6 +80,31 @@ Command-line Parsing .. kernel-doc:: lib/cmdline.c :export: +Sorting +------- + +.. kernel-doc:: lib/sort.c + :export: + +.. kernel-doc:: lib/list_sort.c + :export: + +Text Searching +-------------- + +.. kernel-doc:: lib/textsearch.c + :doc: ts_intro + +.. kernel-doc:: lib/textsearch.c + :export: + +.. kernel-doc:: include/linux/textsearch.h + :functions: textsearch_find textsearch_next \ + textsearch_get_pattern textsearch_get_pattern_len + +CRC and Math Functions in Linux +=============================== + CRC Functions ------------- @@ -103,9 +128,6 @@ CRC Functions .. kernel-doc:: lib/crc-itu-t.c :export: -Math Functions in Linux -======================= - Base 2 log and power Functions ------------------------------ @@ -127,15 +149,6 @@ Division Functions .. kernel-doc:: lib/gcd.c :export: -Sorting -------- - -.. kernel-doc:: lib/sort.c - :export: - -.. kernel-doc:: lib/list_sort.c - :export: - UUID/GUID --------- diff --git a/Documentation/core-api/refcount-vs-atomic.rst b/Documentation/core-api/refcount-vs-atomic.rst index 83351c258cdb..322851bada16 100644 --- a/Documentation/core-api/refcount-vs-atomic.rst +++ b/Documentation/core-api/refcount-vs-atomic.rst @@ -17,7 +17,7 @@ in order to help maintainers validate their code against the change in these memory ordering guarantees. The terms used through this document try to follow the formal LKMM defined in -github.com/aparri/memory-model/blob/master/Documentation/explanation.txt +tools/memory-model/Documentation/explanation.txt. memory-barriers.txt and atomic_t.txt provide more background to the memory ordering in general and for atomic operations specifically. diff --git a/Documentation/cpu-freq/core.txt b/Documentation/cpu-freq/core.txt index 978463a7c81e..073f128af5a7 100644 --- a/Documentation/cpu-freq/core.txt +++ b/Documentation/cpu-freq/core.txt @@ -97,12 +97,10 @@ flags - flags of the cpufreq driver ================================================================== For details about OPP, see Documentation/power/opp.txt -dev_pm_opp_init_cpufreq_table - cpufreq framework typically is initialized with - cpufreq_table_validate_and_show() which is provided with the list of - frequencies that are available for operation. This function provides - a ready to use conversion routine to translate the OPP layer's internal - information about the available frequencies into a format readily - providable to cpufreq. +dev_pm_opp_init_cpufreq_table - + This function provides a ready to use conversion routine to translate + the OPP layer's internal information about the available frequencies + into a format readily providable to cpufreq. WARNING: Do not use this function in interrupt context. @@ -112,7 +110,7 @@ dev_pm_opp_init_cpufreq_table - cpufreq framework typically is initialized with /* Do things */ r = dev_pm_opp_init_cpufreq_table(dev, &freq_table); if (!r) - cpufreq_table_validate_and_show(policy, freq_table); + policy->freq_table = freq_table; /* Do other things */ } diff --git a/Documentation/cpu-freq/cpu-drivers.txt b/Documentation/cpu-freq/cpu-drivers.txt index 61546ac578d6..6e353d00cdc6 100644 --- a/Documentation/cpu-freq/cpu-drivers.txt +++ b/Documentation/cpu-freq/cpu-drivers.txt @@ -259,10 +259,8 @@ CPUFREQ_ENTRY_INVALID. The entries don't need to be in sorted in any particular order, but if they are cpufreq core will do DVFS a bit quickly for them as search for best match is faster. -By calling cpufreq_table_validate_and_show(), the cpuinfo.min_freq and -cpuinfo.max_freq values are detected, and policy->min and policy->max -are set to the same values. This is helpful for the per-CPU -initialization stage. +The cpufreq table is verified automatically by the core if the policy contains a +valid pointer in its policy->freq_table field. cpufreq_frequency_table_verify() assures that at least one valid frequency is within policy->min and policy->max, and all other criteria diff --git a/Documentation/cpuidle/sysfs.txt b/Documentation/cpuidle/sysfs.txt index b6f44f490ed7..d1587f434e7b 100644 --- a/Documentation/cpuidle/sysfs.txt +++ b/Documentation/cpuidle/sysfs.txt @@ -40,6 +40,7 @@ total 0 -r--r--r-- 1 root root 4096 Feb 8 10:42 latency -r--r--r-- 1 root root 4096 Feb 8 10:42 name -r--r--r-- 1 root root 4096 Feb 8 10:42 power +-r--r--r-- 1 root root 4096 Feb 8 10:42 residency -r--r--r-- 1 root root 4096 Feb 8 10:42 time -r--r--r-- 1 root root 4096 Feb 8 10:42 usage @@ -50,6 +51,7 @@ total 0 -r--r--r-- 1 root root 4096 Feb 8 10:42 latency -r--r--r-- 1 root root 4096 Feb 8 10:42 name -r--r--r-- 1 root root 4096 Feb 8 10:42 power +-r--r--r-- 1 root root 4096 Feb 8 10:42 residency -r--r--r-- 1 root root 4096 Feb 8 10:42 time -r--r--r-- 1 root root 4096 Feb 8 10:42 usage @@ -60,6 +62,7 @@ total 0 -r--r--r-- 1 root root 4096 Feb 8 10:42 latency -r--r--r-- 1 root root 4096 Feb 8 10:42 name -r--r--r-- 1 root root 4096 Feb 8 10:42 power +-r--r--r-- 1 root root 4096 Feb 8 10:42 residency -r--r--r-- 1 root root 4096 Feb 8 10:42 time -r--r--r-- 1 root root 4096 Feb 8 10:42 usage @@ -70,6 +73,7 @@ total 0 -r--r--r-- 1 root root 4096 Feb 8 10:42 latency -r--r--r-- 1 root root 4096 Feb 8 10:42 name -r--r--r-- 1 root root 4096 Feb 8 10:42 power +-r--r--r-- 1 root root 4096 Feb 8 10:42 residency -r--r--r-- 1 root root 4096 Feb 8 10:42 time -r--r--r-- 1 root root 4096 Feb 8 10:42 usage -------------------------------------------------------------------------------- @@ -78,6 +82,8 @@ total 0 * desc : Small description about the idle state (string) * disable : Option to disable this idle state (bool) -> see note below * latency : Latency to exit out of this idle state (in microseconds) +* residency : Time after which a state becomes more effecient than any + shallower state (in microseconds) * name : Name of the idle state (string) * power : Power consumed while in this idle state (in milliwatts) * time : Total time spent in this idle state (in microseconds) diff --git a/Documentation/crypto/index.rst b/Documentation/crypto/index.rst index 94c4786f2573..c4ff5d791233 100644 --- a/Documentation/crypto/index.rst +++ b/Documentation/crypto/index.rst @@ -20,5 +20,6 @@ for cryptographic use cases, as well as programming examples. architecture devel-algos userspace-if + crypto_engine api api-samples diff --git a/Documentation/dell_rbu.txt b/Documentation/dell_rbu.txt index 0fdb6aa2704c..5d1ce7bcd04d 100644 --- a/Documentation/dell_rbu.txt +++ b/Documentation/dell_rbu.txt @@ -121,10 +121,7 @@ read back the image downloaded. .. note:: - This driver requires a patch for firmware_class.c which has the modified - request_firmware_nowait function. - - Also after updating the BIOS image a user mode application needs to execute + After updating the BIOS image a user mode application needs to execute code which sends the BIOS update request to the BIOS. So on the next reboot the BIOS knows about the new image downloaded and it updates itself. Also don't unload the rbu driver if the image has to be updated. diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst index f7a18f274357..aabc8738b3d8 100644 --- a/Documentation/dev-tools/kasan.rst +++ b/Documentation/dev-tools/kasan.rst @@ -120,7 +120,7 @@ A typical out of bounds access report looks like this:: The header of the report discribe what kind of bug happened and what kind of access caused it. It's followed by the description of the accessed slub object -(see 'SLUB Debug output' section in Documentation/vm/slub.txt for details) and +(see 'SLUB Debug output' section in Documentation/vm/slub.rst for details) and the description of the accessed memory page. In the last section the report shows memory state around the accessed address. diff --git a/Documentation/dev-tools/kselftest.rst b/Documentation/dev-tools/kselftest.rst index e80850eefe13..3bf371a938d0 100644 --- a/Documentation/dev-tools/kselftest.rst +++ b/Documentation/dev-tools/kselftest.rst @@ -151,6 +151,11 @@ Contributing new tests (details) TEST_FILES, TEST_GEN_FILES mean it is the file which is used by test. + * First use the headers inside the kernel source and/or git repo, and then the + system headers. Headers for the kernel release as opposed to headers + installed by the distro on the system should be the primary focus to be able + to find regressions. + Test Harness ============ diff --git a/Documentation/device-mapper/thin-provisioning.txt b/Documentation/device-mapper/thin-provisioning.txt index 4bcd4b7f79f9..3d01948ea061 100644 --- a/Documentation/device-mapper/thin-provisioning.txt +++ b/Documentation/device-mapper/thin-provisioning.txt @@ -264,7 +264,10 @@ i) Constructor data device, but just remove the mapping. read_only: Don't allow any changes to be made to the pool - metadata. + metadata. This mode is only available after the + thin-pool has been created and first used in full + read/write mode. It cannot be specified on initial + thin-pool creation. error_if_no_space: Error IOs, instead of queueing, if no space. diff --git a/Documentation/device-mapper/verity.txt b/Documentation/device-mapper/verity.txt index 89fd8f9a259f..b3d2e4a42255 100644 --- a/Documentation/device-mapper/verity.txt +++ b/Documentation/device-mapper/verity.txt @@ -109,6 +109,17 @@ fec_start <offset> This is the offset, in <data_block_size> blocks, from the start of the FEC device to the beginning of the encoding data. +check_at_most_once + Verify data blocks only the first time they are read from the data device, + rather than every time. This reduces the overhead of dm-verity so that it + can be used on systems that are memory and/or CPU constrained. However, it + provides a reduced level of security because only offline tampering of the + data device's content will be detected, not online tampering. + + Hash blocks are still verified each time they are read from the hash device, + since verification of hash blocks is less performance critical than data + blocks, and a hash block will not be verified any more after all the data + blocks it covers have been verified anyway. Theory of operation =================== diff --git a/Documentation/devicetree/bindings/arm/arm,scmi.txt b/Documentation/devicetree/bindings/arm/arm,scmi.txt new file mode 100644 index 000000000000..5f3719ab7075 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/arm,scmi.txt @@ -0,0 +1,179 @@ +System Control and Management Interface (SCMI) Message Protocol +---------------------------------------------------------- + +The SCMI is intended to allow agents such as OSPM to manage various functions +that are provided by the hardware platform it is running on, including power +and performance functions. + +This binding is intended to define the interface the firmware implementing +the SCMI as described in ARM document number ARM DUI 0922B ("ARM System Control +and Management Interface Platform Design Document")[0] provide for OSPM in +the device tree. + +Required properties: + +The scmi node with the following properties shall be under the /firmware/ node. + +- compatible : shall be "arm,scmi" +- mboxes: List of phandle and mailbox channel specifiers. It should contain + exactly one or two mailboxes, one for transmitting messages("tx") + and another optional for receiving the notifications("rx") if + supported. +- shmem : List of phandle pointing to the shared memory(SHM) area as per + generic mailbox client binding. +- #address-cells : should be '1' if the device has sub-nodes, maps to + protocol identifier for a given sub-node. +- #size-cells : should be '0' as 'reg' property doesn't have any size + associated with it. + +Optional properties: + +- mbox-names: shall be "tx" or "rx" depending on mboxes entries. + +See Documentation/devicetree/bindings/mailbox/mailbox.txt for more details +about the generic mailbox controller and client driver bindings. + +The mailbox is the only permitted method of calling the SCMI firmware. +Mailbox doorbell is used as a mechanism to alert the presence of a +messages and/or notification. + +Each protocol supported shall have a sub-node with corresponding compatible +as described in the following sections. If the platform supports dedicated +communication channel for a particular protocol, the 3 properties namely: +mboxes, mbox-names and shmem shall be present in the sub-node corresponding +to that protocol. + +Clock/Performance bindings for the clocks/OPPs based on SCMI Message Protocol +------------------------------------------------------------ + +This binding uses the common clock binding[1]. + +Required properties: +- #clock-cells : Should be 1. Contains the Clock ID value used by SCMI commands. + +Power domain bindings for the power domains based on SCMI Message Protocol +------------------------------------------------------------ + +This binding for the SCMI power domain providers uses the generic power +domain binding[2]. + +Required properties: + - #power-domain-cells : Should be 1. Contains the device or the power + domain ID value used by SCMI commands. + +Sensor bindings for the sensors based on SCMI Message Protocol +-------------------------------------------------------------- +SCMI provides an API to access the various sensors on the SoC. + +Required properties: +- #thermal-sensor-cells: should be set to 1. This property follows the + thermal device tree bindings[3]. + + Valid cell values are raw identifiers (Sensor ID) + as used by the firmware. Refer to platform details + for your implementation for the IDs to use. + +SRAM and Shared Memory for SCMI +------------------------------- + +A small area of SRAM is reserved for SCMI communication between application +processors and SCP. + +The properties should follow the generic mmio-sram description found in [4] + +Each sub-node represents the reserved area for SCMI. + +Required sub-node properties: +- reg : The base offset and size of the reserved area with the SRAM +- compatible : should be "arm,scmi-shmem" for Non-secure SRAM based + shared memory + +[0] http://infocenter.arm.com/help/topic/com.arm.doc.den0056a/index.html +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt +[2] Documentation/devicetree/bindings/power/power_domain.txt +[3] Documentation/devicetree/bindings/thermal/thermal.txt +[4] Documentation/devicetree/bindings/sram/sram.txt + +Example: + +sram@50000000 { + compatible = "mmio-sram"; + reg = <0x0 0x50000000 0x0 0x10000>; + + #address-cells = <1>; + #size-cells = <1>; + ranges = <0 0x0 0x50000000 0x10000>; + + cpu_scp_lpri: scp-shmem@0 { + compatible = "arm,scmi-shmem"; + reg = <0x0 0x200>; + }; + + cpu_scp_hpri: scp-shmem@200 { + compatible = "arm,scmi-shmem"; + reg = <0x200 0x200>; + }; +}; + +mailbox@40000000 { + .... + #mbox-cells = <1>; + reg = <0x0 0x40000000 0x0 0x10000>; +}; + +firmware { + + ... + + scmi { + compatible = "arm,scmi"; + mboxes = <&mailbox 0 &mailbox 1>; + mbox-names = "tx", "rx"; + shmem = <&cpu_scp_lpri &cpu_scp_hpri>; + #address-cells = <1>; + #size-cells = <0>; + + scmi_devpd: protocol@11 { + reg = <0x11>; + #power-domain-cells = <1>; + }; + + scmi_dvfs: protocol@13 { + reg = <0x13>; + #clock-cells = <1>; + }; + + scmi_clk: protocol@14 { + reg = <0x14>; + #clock-cells = <1>; + }; + + scmi_sensors0: protocol@15 { + reg = <0x15>; + #thermal-sensor-cells = <1>; + }; + }; +}; + +cpu@0 { + ... + reg = <0 0>; + clocks = <&scmi_dvfs 0>; +}; + +hdlcd@7ff60000 { + ... + reg = <0 0x7ff60000 0 0x1000>; + clocks = <&scmi_clk 4>; + power-domains = <&scmi_devpd 1>; +}; + +thermal-zones { + soc_thermal { + polling-delay-passive = <100>; + polling-delay = <1000>; + /* sensor ID */ + thermal-sensors = <&scmi_sensors0 3>; + ... + }; +}; diff --git a/Documentation/devicetree/bindings/arm/cpu-enable-method/nuvoton,npcm750-smp b/Documentation/devicetree/bindings/arm/cpu-enable-method/nuvoton,npcm750-smp new file mode 100644 index 000000000000..8e043301e28e --- /dev/null +++ b/Documentation/devicetree/bindings/arm/cpu-enable-method/nuvoton,npcm750-smp @@ -0,0 +1,42 @@ +========================================================= +Secondary CPU enable-method "nuvoton,npcm750-smp" binding +========================================================= + +To apply to all CPUs, a single "nuvoton,npcm750-smp" enable method should be +defined in the "cpus" node. + +Enable method name: "nuvoton,npcm750-smp" +Compatible machines: "nuvoton,npcm750" +Compatible CPUs: "arm,cortex-a9" +Related properties: (none) + +Note: +This enable method needs valid nodes compatible with "arm,cortex-a9-scu" and +"nuvoton,npcm750-gcr". + +Example: + + cpus { + #address-cells = <1>; + #size-cells = <0>; + enable-method = "nuvoton,npcm750-smp"; + + cpu@0 { + device_type = "cpu"; + compatible = "arm,cortex-a9"; + clocks = <&clk NPCM7XX_CLK_CPU>; + clock-names = "clk_cpu"; + reg = <0>; + next-level-cache = <&L2>; + }; + + cpu@1 { + device_type = "cpu"; + compatible = "arm,cortex-a9"; + clocks = <&clk NPCM7XX_CLK_CPU>; + clock-names = "clk_cpu"; + reg = <1>; + next-level-cache = <&L2>; + }; + }; + diff --git a/Documentation/devicetree/bindings/arm/cpus.txt b/Documentation/devicetree/bindings/arm/cpus.txt index f4a777039f03..29e1dc5d506d 100644 --- a/Documentation/devicetree/bindings/arm/cpus.txt +++ b/Documentation/devicetree/bindings/arm/cpus.txt @@ -185,6 +185,7 @@ described below. "nvidia,tegra186-denver" "qcom,krait" "qcom,kryo" + "qcom,kryo385" "qcom,scorpion" - enable-method Value type: <stringlist> @@ -198,6 +199,7 @@ described below. "actions,s500-smp" "allwinner,sun6i-a31" "allwinner,sun8i-a23" + "allwinner,sun9i-a80-smp" "amlogic,meson8-smp" "amlogic,meson8b-smp" "arm,realview-smp" diff --git a/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt b/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt new file mode 100644 index 000000000000..10bd35f9207f --- /dev/null +++ b/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt @@ -0,0 +1,33 @@ +Hisilicon Hip06 Low Pin Count device + Hisilicon Hip06 SoCs implement a Low Pin Count (LPC) controller, which + provides I/O access to some legacy ISA devices. + Hip06 is based on arm64 architecture where there is no I/O space. So, the + I/O ports here are not CPU addresses, and there is no 'ranges' property in + LPC device node. + +Required properties: +- compatible: value should be as follows: + (a) "hisilicon,hip06-lpc" + (b) "hisilicon,hip07-lpc" +- #address-cells: must be 2 which stick to the ISA/EISA binding doc. +- #size-cells: must be 1 which stick to the ISA/EISA binding doc. +- reg: base memory range where the LPC register set is mapped. + +Note: + The node name before '@' must be "isa" to represent the binding stick to the + ISA/EISA binding specification. + +Example: + +isa@a01b0000 { + compatible = "hisilicon,hip06-lpc"; + #address-cells = <2>; + #size-cells = <1>; + reg = <0x0 0xa01b0000 0x0 0x1000>; + + ipmi0: bt@e4 { + compatible = "ipmi-bt"; + device_type = "ipmi"; + reg = <0x01 0xe4 0x04>; + }; +}; diff --git a/Documentation/devicetree/bindings/arm/mediatek.txt b/Documentation/devicetree/bindings/arm/mediatek.txt index 91d517849483..7d21ab37c19c 100644 --- a/Documentation/devicetree/bindings/arm/mediatek.txt +++ b/Documentation/devicetree/bindings/arm/mediatek.txt @@ -50,6 +50,15 @@ Supported boards: - Reference board variant 1 for MT7622: Required root node properties: - compatible = "mediatek,mt7622-rfb1", "mediatek,mt7622"; +- Reference board for MT7623a with eMMC: + Required root node properties: + - compatible = "mediatek,mt7623a-rfb-emmc", "mediatek,mt7623"; +- Reference board for MT7623a with NAND: + Required root node properties: + - compatible = "mediatek,mt7623a-rfb-nand", "mediatek,mt7623"; +- Reference board for MT7623n with eMMC: + Required root node properties: + - compatible = "mediatek,mt7623n-rfb-emmc", "mediatek,mt7623"; - Reference board for MT7623n with NAND: Required root node properties: - compatible = "mediatek,mt7623n-rfb-nand", "mediatek,mt7623"; diff --git a/Documentation/devicetree/bindings/arm/mediatek/mediatek,audsys.txt b/Documentation/devicetree/bindings/arm/mediatek/mediatek,audsys.txt index 9b8f578d5e19..34a69ba67f13 100644 --- a/Documentation/devicetree/bindings/arm/mediatek/mediatek,audsys.txt +++ b/Documentation/devicetree/bindings/arm/mediatek/mediatek,audsys.txt @@ -6,6 +6,7 @@ The MediaTek AUDSYS controller provides various clocks to the system. Required Properties: - compatible: Should be one of: + - "mediatek,mt2701-audsys", "syscon" - "mediatek,mt7622-audsys", "syscon" - #clock-cells: Must be 1 @@ -13,10 +14,19 @@ The AUDSYS controller uses the common clk binding from Documentation/devicetree/bindings/clock/clock-bindings.txt The available clocks are defined in dt-bindings/clock/mt*-clk.h. +Required sub-nodes: +------- +For common binding part and usage, refer to +../sonud/mt2701-afe-pcm.txt. + Example: -audsys: audsys@11220000 { - compatible = "mediatek,mt7622-audsys", "syscon"; - reg = <0 0x11220000 0 0x1000>; - #clock-cells = <1>; -}; + audsys: clock-controller@11220000 { + compatible = "mediatek,mt7622-audsys", "syscon"; + reg = <0 0x11220000 0 0x2000>; + #clock-cells = <1>; + + afe: audio-controller { + ... + }; + }; diff --git a/Documentation/devicetree/bindings/arm/mediatek/mediatek,ethsys.txt b/Documentation/devicetree/bindings/arm/mediatek/mediatek,ethsys.txt index 6cc7840ff37a..8f5335b480ac 100644 --- a/Documentation/devicetree/bindings/arm/mediatek/mediatek,ethsys.txt +++ b/Documentation/devicetree/bindings/arm/mediatek/mediatek,ethsys.txt @@ -9,6 +9,7 @@ Required Properties: - "mediatek,mt2701-ethsys", "syscon" - "mediatek,mt7622-ethsys", "syscon" - #clock-cells: Must be 1 +- #reset-cells: Must be 1 The ethsys controller uses the common clk binding from Documentation/devicetree/bindings/clock/clock-bindings.txt diff --git a/Documentation/devicetree/bindings/arm/mediatek/mediatek,pciesys.txt b/Documentation/devicetree/bindings/arm/mediatek/mediatek,pciesys.txt index d5d5f1227665..7fe5dc6097a6 100644 --- a/Documentation/devicetree/bindings/arm/mediatek/mediatek,pciesys.txt +++ b/Documentation/devicetree/bindings/arm/mediatek/mediatek,pciesys.txt @@ -8,6 +8,7 @@ Required Properties: - compatible: Should be: - "mediatek,mt7622-pciesys", "syscon" - #clock-cells: Must be 1 +- #reset-cells: Must be 1 The PCIESYS controller uses the common clk binding from Documentation/devicetree/bindings/clock/clock-bindings.txt @@ -19,4 +20,5 @@ pciesys: pciesys@1a100800 { compatible = "mediatek,mt7622-pciesys", "syscon"; reg = <0 0x1a100800 0 0x1000>; #clock-cells = <1>; + #reset-cells = <1>; }; diff --git a/Documentation/devicetree/bindings/arm/mediatek/mediatek,ssusbsys.txt b/Documentation/devicetree/bindings/arm/mediatek/mediatek,ssusbsys.txt index 00760019da00..b8184da2508c 100644 --- a/Documentation/devicetree/bindings/arm/mediatek/mediatek,ssusbsys.txt +++ b/Documentation/devicetree/bindings/arm/mediatek/mediatek,ssusbsys.txt @@ -8,6 +8,7 @@ Required Properties: - compatible: Should be: - "mediatek,mt7622-ssusbsys", "syscon" - #clock-cells: Must be 1 +- #reset-cells: Must be 1 The SSUSBSYS controller uses the common clk binding from Documentation/devicetree/bindings/clock/clock-bindings.txt @@ -19,4 +20,5 @@ ssusbsys: ssusbsys@1a000000 { compatible = "mediatek,mt7622-ssusbsys", "syscon"; reg = <0 0x1a000000 0 0x1000>; #clock-cells = <1>; + #reset-cells = <1>; }; diff --git a/Documentation/devicetree/bindings/arm/npcm/npcm.txt b/Documentation/devicetree/bindings/arm/npcm/npcm.txt new file mode 100644 index 000000000000..2d87d9ecea85 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/npcm/npcm.txt @@ -0,0 +1,6 @@ +NPCM Platforms Device Tree Bindings +----------------------------------- +NPCM750 SoC +Required root node properties: + - compatible = "nuvoton,npcm750"; + diff --git a/Documentation/devicetree/bindings/arm/omap/ctrl.txt b/Documentation/devicetree/bindings/arm/omap/ctrl.txt index ce8dabf8c0f9..f35b77920786 100644 --- a/Documentation/devicetree/bindings/arm/omap/ctrl.txt +++ b/Documentation/devicetree/bindings/arm/omap/ctrl.txt @@ -25,6 +25,7 @@ Required properties: "ti,omap4-scm-padconf-wkup" "ti,omap5-scm-core" "ti,omap5-scm-padconf-core" + "ti,omap5-scm-wkup-pad-conf" "ti,dra7-scm-core" - reg: Contains Control Module register address range (base address and length) diff --git a/Documentation/devicetree/bindings/arm/omap/mpu.txt b/Documentation/devicetree/bindings/arm/omap/mpu.txt index 763695db2bd9..f301e636fd52 100644 --- a/Documentation/devicetree/bindings/arm/omap/mpu.txt +++ b/Documentation/devicetree/bindings/arm/omap/mpu.txt @@ -13,6 +13,13 @@ Required properties: Optional properties: - sram: Phandle to the ocmcram node +am335x and am437x only: +- pm-sram: Phandles to ocmcram nodes to be used for power management. + First should be type 'protect-exec' for the driver to use to copy + and run PM functions, second should be regular pool to be used for + data region for code. See Documentation/devicetree/bindings/sram/sram.txt + for more details. + Examples: - For an OMAP5 SMP system: @@ -36,3 +43,12 @@ mpu { compatible = "ti,omap3-mpu"; ti,hwmods = "mpu"; }; + +- For an AM335x system: + +mpu { + compatible = "ti,omap3-mpu"; + ti,hwmods = "mpu"; + pm-sram = <&pm_sram_code + &pm_sram_data>; +}; diff --git a/Documentation/devicetree/bindings/arm/qcom.txt b/Documentation/devicetree/bindings/arm/qcom.txt index 0ed4d39d7fe1..ee532e705d6c 100644 --- a/Documentation/devicetree/bindings/arm/qcom.txt +++ b/Documentation/devicetree/bindings/arm/qcom.txt @@ -26,6 +26,7 @@ The 'SoC' element must be one of the following strings: msm8996 mdm9615 ipq8074 + sdm845 The 'board' element must be one of the following strings: diff --git a/Documentation/devicetree/bindings/arm/rockchip.txt b/Documentation/devicetree/bindings/arm/rockchip.txt index 326d24bca1a9..1c1d62d03c4f 100644 --- a/Documentation/devicetree/bindings/arm/rockchip.txt +++ b/Documentation/devicetree/bindings/arm/rockchip.txt @@ -50,6 +50,10 @@ Rockchip platforms device tree bindings Required root node properties: - compatible = "firefly,firefly-rk3399", "rockchip,rk3399"; +- Firefly roc-rk3328-cc board: + Required root node properties: + - compatible = "firefly,roc-rk3328-cc", "rockchip,rk3328"; + - ChipSPARK PopMetal-RK3288 board: Required root node properties: - compatible = "chipspark,popmetal-rk3288", "rockchip,rk3288"; @@ -181,10 +185,18 @@ Rockchip platforms device tree bindings Required root node properties: - compatible = "rockchip,rk3399-evb", "rockchip,rk3399"; +- Rockchip RK3399 Sapphire board standalone: + Required root node properties: + - compatible = "rockchip,rk3399-sapphire", "rockchip,rk3399"; + - Rockchip RK3399 Sapphire Excavator board: Required root node properties: - compatible = "rockchip,rk3399-sapphire-excavator", "rockchip,rk3399"; +- Theobroma Systems RK3368-uQ7 Haikou Baseboard: + Required root node properties: + - compatible = "tsd,rk3368-uq7-haikou", "rockchip,rk3368"; + - Theobroma Systems RK3399-Q7 Haikou Baseboard: Required root node properties: - compatible = "tsd,rk3399-q7-haikou", "rockchip,rk3399"; diff --git a/Documentation/devicetree/bindings/arm/samsung/pmu.txt b/Documentation/devicetree/bindings/arm/samsung/pmu.txt index 779f5614bcee..16685787d2bd 100644 --- a/Documentation/devicetree/bindings/arm/samsung/pmu.txt +++ b/Documentation/devicetree/bindings/arm/samsung/pmu.txt @@ -43,6 +43,12 @@ following properties: - interrupt-parent: a phandle indicating which interrupt controller this PMU signals interrupts to. + +Optional nodes: + +- nodes defining the restart and poweroff syscon children + + Example : pmu_system_controller: system-controller@10040000 { compatible = "samsung,exynos5250-pmu", "syscon"; diff --git a/Documentation/devicetree/bindings/arm/samsung/samsung-boards.txt b/Documentation/devicetree/bindings/arm/samsung/samsung-boards.txt index 469ac98ecf8f..14510b215480 100644 --- a/Documentation/devicetree/bindings/arm/samsung/samsung-boards.txt +++ b/Documentation/devicetree/bindings/arm/samsung/samsung-boards.txt @@ -9,7 +9,11 @@ Required root node properties: - "samsung,smdkv310" - for Exynos4210-based Samsung SMDKV310 eval board. - "samsung,trats" - for Exynos4210-based Tizen Reference board. - "samsung,universal_c210" - for Exynos4210-based Samsung board. + - "samsung,i9300" - for Exynos4412-based Samsung GT-I9300 board. + - "samsung,i9305" - for Exynos4412-based Samsung GT-I9305 board. + - "samsung,midas" - for Exynos4412-based Samsung Midas board. - "samsung,smdk4412", - for Exynos4412-based Samsung SMDK4412 eval board. + - "samsung,n710x" - for Exynos4412-based Samsung GT-N7100/GT-N7105 board. - "samsung,trats2" - for Exynos4412-based Tizen Reference board. - "samsung,smdk5250" - for Exynos5250-based Samsung SMDK5250 eval board. - "samsung,xyref5260" - for Exynos5260-based Samsung board. diff --git a/Documentation/devicetree/bindings/arm/shmobile.txt b/Documentation/devicetree/bindings/arm/shmobile.txt index 5c3af7ef0761..d3d1df97834f 100644 --- a/Documentation/devicetree/bindings/arm/shmobile.txt +++ b/Documentation/devicetree/bindings/arm/shmobile.txt @@ -39,8 +39,12 @@ SoCs: compatible = "renesas,r8a7795" - R-Car M3-W (R8A77960) compatible = "renesas,r8a7796" + - R-Car M3-N (R8A77965) + compatible = "renesas,r8a77965" - R-Car V3M (R8A77970) compatible = "renesas,r8a77970" + - R-Car V3H (R8A77980) + compatible = "renesas,r8a77980" - R-Car D3 (R8A77995) compatible = "renesas,r8a77995" @@ -52,11 +56,13 @@ Boards: - APE6-EVM compatible = "renesas,ape6evm", "renesas,r8a73a4" - Atmark Techno Armadillo-800 EVA - compatible = "renesas,armadillo800eva" + compatible = "renesas,armadillo800eva", "renesas,r8a7740" - Blanche (RTP0RC7792SEB00010S) compatible = "renesas,blanche", "renesas,r8a7792" - BOCK-W compatible = "renesas,bockw", "renesas,r8a7778" + - Condor (RTP0RC77980SEB0010SS/RTP0RC77980SEB0010SA01) + compatible = "renesas,condor", "renesas,r8a77980" - Draak (RTP0RC77995SEB0010S) compatible = "renesas,draak", "renesas,r8a77995" - Eagle (RTP0RC77970SEB0010S) @@ -102,19 +108,25 @@ Boards: compatible = "renesas,salvator-x", "renesas,r8a7795" - Salvator-X (RTP0RC7796SIPB0011S) compatible = "renesas,salvator-x", "renesas,r8a7796" + - Salvator-X (RTP0RC7796SIPB0011S (M3N)) + compatible = "renesas,salvator-x", "renesas,r8a77965" - Salvator-XS (Salvator-X 2nd version, RTP0RC7795SIPB0012S) compatible = "renesas,salvator-xs", "renesas,r8a7795" - Salvator-XS (Salvator-X 2nd version, RTP0RC7796SIPB0012S) compatible = "renesas,salvator-xs", "renesas,r8a7796" + - Salvator-XS (Salvator-X 2nd version, RTP0RC77965SIPB012S) + compatible = "renesas,salvator-xs", "renesas,r8a77965" - SILK (RTP0RC7794LCB00011S) compatible = "renesas,silk", "renesas,r8a7794" - SK-RZG1E (YR8A77450S000BE) compatible = "renesas,sk-rzg1e", "renesas,r8a7745" - SK-RZG1M (YR8A77430S000BE) compatible = "renesas,sk-rzg1m", "renesas,r8a7743" - - V3MSK + - Stout (ADAS Starterkit, Y-R-CAR-ADAS-SKH2-BOARD) + compatible = "renesas,stout", "renesas,r8a7790" + - V3MSK (Y-ASK-RCAR-V3M-WS10) compatible = "renesas,v3msk", "renesas,r8a77970" - - Wheat + - Wheat (RTP0RC7792ASKB0000JE) compatible = "renesas,wheat", "renesas,r8a7792" diff --git a/Documentation/devicetree/bindings/arm/stm32.txt b/Documentation/devicetree/bindings/arm/stm32.txt index 05762b08a7bb..6808ed9ddfd5 100644 --- a/Documentation/devicetree/bindings/arm/stm32.txt +++ b/Documentation/devicetree/bindings/arm/stm32.txt @@ -7,3 +7,4 @@ using one of the following compatible strings: st,stm32f469 st,stm32f746 st,stm32h743 + st,stm32mp157 diff --git a/Documentation/devicetree/bindings/arm/sunxi/smp-sram.txt b/Documentation/devicetree/bindings/arm/sunxi/smp-sram.txt new file mode 100644 index 000000000000..082e6a9382d3 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/sunxi/smp-sram.txt @@ -0,0 +1,44 @@ +Allwinner SRAM for smp bringup: +------------------------------------------------ + +Allwinner's A80 SoC uses part of the secure sram for hotplugging of the +primary core (cpu0). Once the core gets powered up it checks if a magic +value is set at a specific location. If it is then the BROM will jump +to the software entry address, instead of executing a standard boot. + +Therefore a reserved section sub-node has to be added to the mmio-sram +declaration. + +Note that this is separate from the Allwinner SRAM controller found in +../../sram/sunxi-sram.txt. This SRAM is secure only and not mappable to +any device. + +Also there are no "secure-only" properties. The implementation should +check if this SRAM is usable first. + +Required sub-node properties: +- compatible : depending on the SoC this should be one of: + "allwinner,sun9i-a80-smp-sram" + +The rest of the properties should follow the generic mmio-sram discription +found in ../../misc/sram.txt + +Example: + + sram_b: sram@20000 { + /* 256 KiB secure SRAM at 0x20000 */ + compatible = "mmio-sram"; + reg = <0x00020000 0x40000>; + #address-cells = <1>; + #size-cells = <1>; + ranges = <0 0x00020000 0x40000>; + + smp-sram@1000 { + /* + * This is checked by BROM to determine if + * cpu0 should jump to SMP entry vector + */ + compatible = "allwinner,sun9i-a80-smp-sram"; + reg = <0x1000 0x8>; + }; + }; diff --git a/Documentation/devicetree/bindings/arm/tegra.txt b/Documentation/devicetree/bindings/arm/tegra.txt index 7f1411bbabf7..32f62bb7006d 100644 --- a/Documentation/devicetree/bindings/arm/tegra.txt +++ b/Documentation/devicetree/bindings/arm/tegra.txt @@ -9,6 +9,12 @@ following compatible values: nvidia,tegra20 nvidia,tegra30 + nvidia,tegra114 + nvidia,tegra124 + nvidia,tegra132 + nvidia,tegra210 + nvidia,tegra186 + nvidia,tegra194 Boards ------------------------------------------- @@ -26,8 +32,18 @@ board-specific compatible values: nvidia,cardhu nvidia,cardhu-a02 nvidia,cardhu-a04 + nvidia,dalmore nvidia,harmony + nvidia,jetson-tk1 + nvidia,norrin + nvidia,p2371-0000 + nvidia,p2371-2180 + nvidia,p2571 + nvidia,p2771-0000 + nvidia,p2972-0000 + nvidia,roth nvidia,seaboard + nvidia,tn7 nvidia,ventana toradex,apalis_t30 toradex,apalis_t30-eval diff --git a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra186-pmc.txt b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra186-pmc.txt index 078a58b0302f..5a3bf7c5a7a0 100644 --- a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra186-pmc.txt +++ b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra186-pmc.txt @@ -3,6 +3,7 @@ NVIDIA Tegra Power Management Controller (PMC) Required properties: - compatible: Should contain one of the following: - "nvidia,tegra186-pmc": for Tegra186 + - "nvidia,tegra194-pmc": for Tegra194 - reg: Must contain an (offset, length) pair of the register set for each entry in reg-names. - reg-names: Must include the following entries: @@ -10,6 +11,7 @@ Required properties: - "wake" - "aotag" - "scratch" + - "misc" (Only for Tegra194) Optional properties: - nvidia,invert-interrupt: If present, inverts the PMU interrupt signal. diff --git a/Documentation/devicetree/bindings/arm/xilinx.txt b/Documentation/devicetree/bindings/arm/xilinx.txt index 1f7995357888..b9043bc35c14 100644 --- a/Documentation/devicetree/bindings/arm/xilinx.txt +++ b/Documentation/devicetree/bindings/arm/xilinx.txt @@ -5,3 +5,59 @@ shall have the following properties. Required root node properties: - compatible = "xlnx,zynq-7000"; + +Additional compatible strings: + +- Xilinx internal board cc108 + "xlnx,zynq-cc108" + +- Xilinx internal board zc770 with different FMC cards + "xlnx,zynq-zc770-xm010" + "xlnx,zynq-zc770-xm011" + "xlnx,zynq-zc770-xm012" + "xlnx,zynq-zc770-xm013" + +- Digilent Zybo Z7 board + "digilent,zynq-zybo-z7" + +--------------------------------------------------------------- + +Xilinx Zynq UltraScale+ MPSoC Platforms Device Tree Bindings + +Boards with ZynqMP SOC based on an ARM Cortex A53 processor +shall have the following properties. + +Required root node properties: + - compatible = "xlnx,zynqmp"; + + +Additional compatible strings: + +- Xilinx internal board zc1232 + "xlnx,zynqmp-zc1232-revA", "xlnx,zynqmp-zc1232" + +- Xilinx internal board zc1254 + "xlnx,zynqmp-zc1254-revA", "xlnx,zynqmp-zc1254" + +- Xilinx internal board zc1275 + "xlnx,zynqmp-zc1275-revA", "xlnx,zynqmp-zc1275" + +- Xilinx internal board zc1751 + "xlnx,zynqmp-zc1751" + +- Xilinx 96boards compatible board zcu100 + "xlnx,zynqmp-zcu100-revC", "xlnx,zynqmp-zcu100" + +- Xilinx evaluation board zcu102 + "xlnx,zynqmp-zcu102-revA", "xlnx,zynqmp-zcu102" + "xlnx,zynqmp-zcu102-revB", "xlnx,zynqmp-zcu102" + "xlnx,zynqmp-zcu102-rev1.0", "xlnx,zynqmp-zcu102" + +- Xilinx evaluation board zcu104 + "xlnx,zynqmp-zcu104-revA", "xlnx,zynqmp-zcu104" + +- Xilinx evaluation board zcu106 + "xlnx,zynqmp-zcu106-revA", "xlnx,zynqmp-zcu106" + +- Xilinx evaluation board zcu111 + "xlnx,zynqmp-zcu111-revA", "xlnx,zynqmp-zcu111" diff --git a/Documentation/devicetree/bindings/ata/ahci-platform.txt b/Documentation/devicetree/bindings/ata/ahci-platform.txt index f4006d3c9fdf..c760ecb81381 100644 --- a/Documentation/devicetree/bindings/ata/ahci-platform.txt +++ b/Documentation/devicetree/bindings/ata/ahci-platform.txt @@ -30,7 +30,6 @@ compatible: Optional properties: - dma-coherent : Present if dma operations are coherent - clocks : a list of phandle + clock specifier pairs -- resets : a list of phandle + reset specifier pairs - target-supply : regulator for SATA target power - phys : reference to the SATA PHY node - phy-names : must be "sata-phy" diff --git a/Documentation/devicetree/bindings/bus/nvidia,tegra20-gmi.txt b/Documentation/devicetree/bindings/bus/nvidia,tegra20-gmi.txt index 3e21eb822811..c1e70621799b 100644 --- a/Documentation/devicetree/bindings/bus/nvidia,tegra20-gmi.txt +++ b/Documentation/devicetree/bindings/bus/nvidia,tegra20-gmi.txt @@ -73,7 +73,7 @@ Example with two SJA1000 CAN controllers connected to the GMI bus. We wrap the controllers with a simple-bus node since they are all connected to the same chip-select (CS4), in this example external address decoding is provided: -gmi@70090000 { +gmi@70009000 { compatible = "nvidia,tegra20-gmi"; reg = <0x70009000 0x1000>; #address-cells = <2>; @@ -84,7 +84,6 @@ gmi@70090000 { reset-names = "gmi"; ranges = <4 0 0xd0000000 0xfffffff>; - bus@4,0 { compatible = "simple-bus"; #address-cells = <1>; @@ -109,7 +108,7 @@ gmi@70090000 { Example with one SJA1000 CAN controller connected to the GMI bus on CS4: -gmi@70090000 { +gmi@70009000 { compatible = "nvidia,tegra20-gmi"; reg = <0x70009000 0x1000>; #address-cells = <2>; @@ -120,7 +119,6 @@ gmi@70090000 { reset-names = "gmi"; ranges = <4 0 0xd0000000 0xfffffff>; - can@4,0 { reg = <4 0 0x100>; nvidia,snor-mux-mode; diff --git a/Documentation/devicetree/bindings/clock/imx6sll-clock.txt b/Documentation/devicetree/bindings/clock/imx6sll-clock.txt new file mode 100644 index 000000000000..fee849d5fdd1 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/imx6sll-clock.txt @@ -0,0 +1,36 @@ +* Clock bindings for Freescale i.MX6 SLL + +Required properties: +- compatible: Should be "fsl,imx6sll-ccm" +- reg: Address and length of the register set +- #clock-cells: Should be <1> +- clocks: list of clock specifiers, must contain an entry for each required + entry in clock-names +- clock-names: should include entries "ckil", "osc", "ipp_di0" and "ipp_di1" + +The clock consumer should specify the desired clock by having the clock +ID in its "clocks" phandle cell. See include/dt-bindings/clock/imx6sll-clock.h +for the full list of i.MX6 SLL clock IDs. + +Examples: + +#include <dt-bindings/clock/imx6sll-clock.h> + +clks: clock-controller@20c4000 { + compatible = "fsl,imx6sll-ccm"; + reg = <0x020c4000 0x4000>; + interrupts = <GIC_SPI 87 IRQ_TYPE_LEVEL_HIGH>, + <GIC_SPI 88 IRQ_TYPE_LEVEL_HIGH>; + #clock-cells = <1>; + clocks = <&ckil>, <&osc>, <&ipp_di0>, <&ipp_di1>; + clock-names = "ckil", "osc", "ipp_di0", "ipp_di1"; +}; + +uart1: serial@2020000 { + compatible = "fsl,imx6sl-uart", "fsl,imx6q-uart", "fsl,imx21-uart"; + reg = <0x02020000 0x4000>; + interrupts = <GIC_SPI 26 IRQ_TYPE_LEVEL_HIGH>; + clocks = <&clks IMX6SLL_CLK_UART1_IPG>, + <&clks IMX6SLL_CLK_UART1_SERIAL>; + clock-names = "ipg", "per"; +}; diff --git a/Documentation/devicetree/bindings/clock/intc_stratix10.txt b/Documentation/devicetree/bindings/clock/intc_stratix10.txt new file mode 100644 index 000000000000..9f4ec5cb5c6b --- /dev/null +++ b/Documentation/devicetree/bindings/clock/intc_stratix10.txt @@ -0,0 +1,20 @@ +Device Tree Clock bindings for Intel's SoCFPGA Stratix10 platform + +This binding uses the common clock binding[1]. + +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt + +Required properties: +- compatible : shall be + "intel,stratix10-clkmgr" + +- reg : shall be the control register offset from CLOCK_MANAGER's base for the clock. + +- #clock-cells : from common clock binding, shall be set to 1. + +Example: + clkmgr: clock-controller@ffd10000 { + compatible = "intel,stratix10-clkmgr"; + reg = <0xffd10000 0x1000>; + #clock-cells = <1>; + }; diff --git a/Documentation/devicetree/bindings/clock/renesas,cpg-mssr.txt b/Documentation/devicetree/bindings/clock/renesas,cpg-mssr.txt index f1890d0777a6..773a5226342f 100644 --- a/Documentation/devicetree/bindings/clock/renesas,cpg-mssr.txt +++ b/Documentation/devicetree/bindings/clock/renesas,cpg-mssr.txt @@ -22,7 +22,9 @@ Required Properties: - "renesas,r8a7794-cpg-mssr" for the r8a7794 SoC (R-Car E2) - "renesas,r8a7795-cpg-mssr" for the r8a7795 SoC (R-Car H3) - "renesas,r8a7796-cpg-mssr" for the r8a7796 SoC (R-Car M3-W) + - "renesas,r8a77965-cpg-mssr" for the r8a77965 SoC (R-Car M3-N) - "renesas,r8a77970-cpg-mssr" for the r8a77970 SoC (R-Car V3M) + - "renesas,r8a77980-cpg-mssr" for the r8a77980 SoC (R-Car V3H) - "renesas,r8a77995-cpg-mssr" for the r8a77995 SoC (R-Car D3) - reg: Base address and length of the memory resource used by the CPG/MSSR @@ -32,8 +34,8 @@ Required Properties: clock-names - clock-names: List of external parent clock names. Valid names are: - "extal" (r8a7743, r8a7745, r8a7790, r8a7791, r8a7792, r8a7793, r8a7794, - r8a7795, r8a7796, r8a77970, r8a77995) - - "extalr" (r8a7795, r8a7796, r8a77970) + r8a7795, r8a7796, r8a77965, r8a77970, r8a77980, r8a77995) + - "extalr" (r8a7795, r8a7796, r8a77965, r8a77970, r8a77980) - "usb_extal" (r8a7743, r8a7745, r8a7790, r8a7791, r8a7793, r8a7794) - #clock-cells: Must be 2 diff --git a/Documentation/devicetree/bindings/clock/rockchip,rk3328-cru.txt b/Documentation/devicetree/bindings/clock/rockchip,rk3328-cru.txt index e71c675ba5da..904ae682ea90 100644 --- a/Documentation/devicetree/bindings/clock/rockchip,rk3328-cru.txt +++ b/Documentation/devicetree/bindings/clock/rockchip,rk3328-cru.txt @@ -32,6 +32,7 @@ clock-output-names: - "clkin_i2s" - external I2S clock - optional, - "gmac_clkin" - external GMAC clock - optional - "phy_50m_out" - output clock of the pll in the mac phy + - "hdmi_phy" - output clock of the hdmi phy pll - optional Example: Clock controller node: diff --git a/Documentation/devicetree/bindings/clock/silabs,si544.txt b/Documentation/devicetree/bindings/clock/silabs,si544.txt new file mode 100644 index 000000000000..b86535b80920 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/silabs,si544.txt @@ -0,0 +1,25 @@ +Binding for Silicon Labs 544 programmable I2C clock generator. + +Reference +This binding uses the common clock binding[1]. Details about the device can be +found in the datasheet[2]. + +[1] Documentation/devicetree/bindings/clock/clock-bindings.txt +[2] Si544 datasheet + https://www.silabs.com/documents/public/data-sheets/si544-datasheet.pdf + +Required properties: + - compatible: One of "silabs,si514a", "silabs,si514b" "silabs,si514c" according + to the speed grade of the chip. + - reg: I2C device address. + - #clock-cells: From common clock bindings: Shall be 0. + +Optional properties: + - clock-output-names: From common clock bindings. Recommended to be "si544". + +Example: + si544: clock-controller@55 { + reg = <0x55>; + #clock-cells = <0>; + compatible = "silabs,si544b"; + }; diff --git a/Documentation/devicetree/bindings/clock/st,stm32mp1-rcc.txt b/Documentation/devicetree/bindings/clock/st,stm32mp1-rcc.txt new file mode 100644 index 000000000000..fb9495ea582c --- /dev/null +++ b/Documentation/devicetree/bindings/clock/st,stm32mp1-rcc.txt @@ -0,0 +1,60 @@ +STMicroelectronics STM32 Peripheral Reset Clock Controller +========================================================== + +The RCC IP is both a reset and a clock controller. + +RCC makes also power management (resume/supend and wakeup interrupt). + +Please also refer to reset.txt for common reset controller binding usage. + +Please also refer to clock-bindings.txt for common clock controller +binding usage. + + +Required properties: +- compatible: "st,stm32mp1-rcc", "syscon" +- reg: should be register base and length as documented in the datasheet +- #clock-cells: 1, device nodes should specify the clock in their + "clocks" property, containing a phandle to the clock device node, + an index specifying the clock to use. +- #reset-cells: Shall be 1 +- interrupts: Should contain a general interrupt line and a interrupt line + to the wake-up of processor (CSTOP). + +Example: + rcc: rcc@50000000 { + compatible = "st,stm32mp1-rcc", "syscon"; + reg = <0x50000000 0x1000>; + #clock-cells = <1>; + #reset-cells = <1>; + interrupts = <GIC_SPI 5 IRQ_TYPE_NONE>, + <GIC_SPI 145 IRQ_TYPE_NONE>; + }; + +Specifying clocks +================= + +All available clocks are defined as preprocessor macros in +dt-bindings/clock/stm32mp1-clks.h header and can be used in device +tree sources. + +Specifying softreset control of devices +======================================= + +Device nodes should specify the reset channel required in their "resets" +property, containing a phandle to the reset device node and an index specifying +which channel to use. +The index is the bit number within the RCC registers bank, starting from RCC +base address. +It is calculated as: index = register_offset / 4 * 32 + bit_offset. +Where bit_offset is the bit offset within the register. + +For example on STM32MP1, for LTDC reset: + ltdc = APB4_RSTSETR_offset / 4 * 32 + LTDC_bit_offset + = 0x180 / 4 * 32 + 0 = 3072 + +The list of valid indices for STM32MP1 is available in: +include/dt-bindings/reset-controller/stm32mp1-resets.h + +This file implements defines like: +#define LTDC_R 3072 diff --git a/Documentation/devicetree/bindings/clock/sunxi-ccu.txt b/Documentation/devicetree/bindings/clock/sunxi-ccu.txt index 4ca21c3a6fc9..460ef27b1008 100644 --- a/Documentation/devicetree/bindings/clock/sunxi-ccu.txt +++ b/Documentation/devicetree/bindings/clock/sunxi-ccu.txt @@ -20,6 +20,7 @@ Required properties : - "allwinner,sun50i-a64-ccu" - "allwinner,sun50i-a64-r-ccu" - "allwinner,sun50i-h5-ccu" + - "allwinner,sun50i-h6-ccu" - "nextthing,gr8-ccu" - reg: Must contain the registers base address and length @@ -31,6 +32,9 @@ Required properties : - #clock-cells : must contain 1 - #reset-cells : must contain 1 +For the main CCU on H6, one more clock is needed: +- "iosc": the SoC's internal frequency oscillator + For the PRCM CCUs on A83T/H3/A64, two more clocks are needed: - "pll-periph": the SoC's peripheral PLL from the main CCU - "iosc": the SoC's internal frequency oscillator diff --git a/Documentation/devicetree/bindings/clock/ti/davinci/da8xx-cfgchip.txt b/Documentation/devicetree/bindings/clock/ti/davinci/da8xx-cfgchip.txt new file mode 100644 index 000000000000..1e03dce99a8f --- /dev/null +++ b/Documentation/devicetree/bindings/clock/ti/davinci/da8xx-cfgchip.txt @@ -0,0 +1,93 @@ +Binding for TI DA8XX/OMAP-L13X/AM17XX/AM18XX CFGCHIP clocks + +TI DA8XX/OMAP-L13X/AM17XX/AM18XX SoCs contain a general purpose set of +registers call CFGCHIPn. Some of these registers function as clock +gates. This document describes the bindings for those clocks. + +All of the clock nodes described below must be child nodes of a CFGCHIP node +(compatible = "ti,da830-cfgchip"). + +USB PHY clocks +-------------- +Required properties: +- compatible: shall be "ti,da830-usb-phy-clocks". +- #clock-cells: from common clock binding; shall be set to 1. +- clocks: phandles to the parent clocks corresponding to clock-names +- clock-names: shall be "fck", "usb_refclkin", "auxclk" + +This node provides two clocks. The clock at index 0 is the USB 2.0 PHY 48MHz +clock and the clock at index 1 is the USB 1.1 PHY 48MHz clock. + +eHRPWM Time Base Clock (TBCLK) +------------------------------ +Required properties: +- compatible: shall be "ti,da830-tbclksync". +- #clock-cells: from common clock binding; shall be set to 0. +- clocks: phandle to the parent clock +- clock-names: shall be "fck" + +PLL DIV4.5 divider +------------------ +Required properties: +- compatible: shall be "ti,da830-div4p5ena". +- #clock-cells: from common clock binding; shall be set to 0. +- clocks: phandle to the parent clock +- clock-names: shall be "pll0_pllout" + +EMIFA clock source (ASYNC1) +--------------------------- +Required properties: +- compatible: shall be "ti,da850-async1-clksrc". +- #clock-cells: from common clock binding; shall be set to 0. +- clocks: phandles to the parent clocks corresponding to clock-names +- clock-names: shall be "pll0_sysclk3", "div4.5" + +ASYNC3 clock source +------------------- +Required properties: +- compatible: shall be "ti,da850-async3-clksrc". +- #clock-cells: from common clock binding; shall be set to 0. +- clocks: phandles to the parent clocks corresponding to clock-names +- clock-names: shall be "pll0_sysclk2", "pll1_sysclk2" + +Examples: + + cfgchip: syscon@1417c { + compatible = "ti,da830-cfgchip", "syscon", "simple-mfd"; + reg = <0x1417c 0x14>; + + usb_phy_clk: usb-phy-clocks { + compatible = "ti,da830-usb-phy-clocks"; + #clock-cells = <1>; + clocks = <&psc1 1>, <&usb_refclkin>, <&pll0_auxclk>; + clock-names = "fck", "usb_refclkin", "auxclk"; + }; + ehrpwm_tbclk: ehrpwm_tbclk { + compatible = "ti,da830-tbclksync"; + #clock-cells = <0>; + clocks = <&psc1 17>; + clock-names = "fck"; + }; + div4p5_clk: div4.5 { + compatible = "ti,da830-div4p5ena"; + #clock-cells = <0>; + clocks = <&pll0_pllout>; + clock-names = "pll0_pllout"; + }; + async1_clk: async1 { + compatible = "ti,da850-async1-clksrc"; + #clock-cells = <0>; + clocks = <&pll0_sysclk 3>, <&div4p5_clk>; + clock-names = "pll0_sysclk3", "div4.5"; + }; + async3_clk: async3 { + compatible = "ti,da850-async3-clksrc"; + #clock-cells = <0>; + clocks = <&pll0_sysclk 2>, <&pll1_sysclk 2>; + clock-names = "pll0_sysclk2", "pll1_sysclk2"; + }; + }; + +Also see: +- Documentation/devicetree/bindings/clock/clock-bindings.txt + diff --git a/Documentation/devicetree/bindings/clock/ti/davinci/pll.txt b/Documentation/devicetree/bindings/clock/ti/davinci/pll.txt new file mode 100644 index 000000000000..36998e184821 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/ti/davinci/pll.txt @@ -0,0 +1,96 @@ +Binding for TI DaVinci PLL Controllers + +The PLL provides clocks to most of the components on the SoC. In addition +to the PLL itself, this controller also contains bypasses, gates, dividers, +an multiplexers for various clock signals. + +Required properties: +- compatible: shall be one of: + - "ti,da850-pll0" for PLL0 on DA850/OMAP-L138/AM18XX + - "ti,da850-pll1" for PLL1 on DA850/OMAP-L138/AM18XX +- reg: physical base address and size of the controller's register area. +- clocks: phandles corresponding to the clock names +- clock-names: names of the clock sources - depends on compatible string + - for "ti,da850-pll0", shall be "clksrc", "extclksrc" + - for "ti,da850-pll1", shall be "clksrc" + +Optional properties: +- ti,clkmode-square-wave: Indicates that the the board is supplying a square + wave input on the OSCIN pin instead of using a crystal oscillator. + This property is only valid when compatible = "ti,da850-pll0". + + +Optional child nodes: + +pllout + Describes the main PLL clock output (before POSTDIV). The node name must + be "pllout". + + Required properties: + - #clock-cells: shall be 0 + +sysclk + Describes the PLLDIVn divider clocks that provide the SYSCLKn clock + domains. The node name must be "sysclk". Consumers of this node should + use "n" in "SYSCLKn" as the index parameter for the clock cell. + + Required properties: + - #clock-cells: shall be 1 + +auxclk + Describes the AUXCLK output of the PLL. The node name must be "auxclk". + This child node is only valid when compatible = "ti,da850-pll0". + + Required properties: + - #clock-cells: shall be 0 + +obsclk + Describes the OBSCLK output of the PLL. The node name must be "obsclk". + + Required properties: + - #clock-cells: shall be 0 + + +Examples: + + pll0: clock-controller@11000 { + compatible = "ti,da850-pll0"; + reg = <0x11000 0x1000>; + clocks = <&ref_clk>, <&pll1_sysclk 3>; + clock-names = "clksrc", "extclksrc"; + ti,clkmode-square-wave; + + pll0_pllout: pllout { + #clock-cells = <0>; + }; + + pll0_sysclk: sysclk { + #clock-cells = <1>; + }; + + pll0_auxclk: auxclk { + #clock-cells = <0>; + }; + + pll0_obsclk: obsclk { + #clock-cells = <0>; + }; + }; + + pll1: clock-controller@21a000 { + compatible = "ti,da850-pll1"; + reg = <0x21a000 0x1000>; + clocks = <&ref_clk>; + clock-names = "clksrc"; + + pll0_sysclk: sysclk { + #clock-cells = <1>; + }; + + pll0_obsclk: obsclk { + #clock-cells = <0>; + }; + }; + +Also see: +- Documentation/devicetree/bindings/clock/clock-bindings.txt diff --git a/Documentation/devicetree/bindings/clock/ti/davinci/psc.txt b/Documentation/devicetree/bindings/clock/ti/davinci/psc.txt new file mode 100644 index 000000000000..dae4ad8e198c --- /dev/null +++ b/Documentation/devicetree/bindings/clock/ti/davinci/psc.txt @@ -0,0 +1,71 @@ +Binding for TI DaVinci Power Sleep Controller (PSC) + +The PSC provides power management, clock gating and reset functionality. It is +primarily used for clocking. + +Required properties: +- compatible: shall be one of: + - "ti,da850-psc0" for PSC0 on DA850/OMAP-L138/AM18XX + - "ti,da850-psc1" for PSC1 on DA850/OMAP-L138/AM18XX +- reg: physical base address and size of the controller's register area +- #clock-cells: from common clock binding; shall be set to 1 +- #power-domain-cells: from generic power domain binding; shall be set to 1. +- clocks: phandles to clocks corresponding to the clock-names property +- clock-names: list of parent clock names - depends on compatible value + - for "ti,da850-psc0", shall be "pll0_sysclk1", "pll0_sysclk2", + "pll0_sysclk4", "pll0_sysclk6", "async1" + - for "ti,da850-psc1", shall be "pll0_sysclk2", "pll0_sysclk4", "async3" + +Optional properties: +- #reset-cells: from reset binding; shall be set to 1 - only applicable when + at least one local domain provides a local reset. + +Consumers: + + Clock, power domain and reset consumers shall use the local power domain + module ID (LPSC) as the index corresponding to the clock cell. Refer to + the device-specific datasheet to find these numbers. NB: Most local + domains only provide a clock/power domain and not a reset. + +Examples: + + psc0: clock-controller@10000 { + compatible = "ti,da850-psc0"; + reg = <0x10000 0x1000>; + #clock-cells = <1>; + #power-domain-cells = <1>; + #reset-cells = <1>; + clocks = <&pll0_sysclk 1>, <&pll0_sysclk 2>, + <&pll0_sysclk 4>, <&pll0_sysclk 6>, <&async1_clk>; + clock_names = "pll0_sysclk1", "pll0_sysclk2", + "pll0_sysclk4", "pll0_sysclk6", "async1"; + }; + psc1: clock-controller@227000 { + compatible = "ti,da850-psc1"; + reg = <0x227000 0x1000>; + #clock-cells = <1>; + #power-domain-cells = <1>; + clocks = <&pll0_sysclk 2>, <&pll0_sysclk 4>, <&async3_clk>; + clock_names = "pll0_sysclk2", "pll0_sysclk4", "async3"; + }; + + /* consumer */ + dsp: dsp@11800000 { + compatible = "ti,da850-dsp"; + reg = <0x11800000 0x40000>, + <0x11e00000 0x8000>, + <0x11f00000 0x8000>, + <0x01c14044 0x4>, + <0x01c14174 0x8>; + reg-names = "l2sram", "l1pram", "l1dram", "host1cfg", "chipsig"; + interrupt-parent = <&intc>; + interrupts = <28>; + clocks = <&psc0 15>; + power-domains = <&psc0 15>; + resets = <&psc0 15>; + }; + +Also see: +- Documentation/devicetree/bindings/clock/clock-bindings.txt +- Documentation/devicetree/bindings/power/power_domain.txt +- Documentation/devicetree/bindings/reset/reset.txt diff --git a/Documentation/devicetree/bindings/clock/ti/divider.txt b/Documentation/devicetree/bindings/clock/ti/divider.txt index 35a6f5c7e5c2..9b13b32974f9 100644 --- a/Documentation/devicetree/bindings/clock/ti/divider.txt +++ b/Documentation/devicetree/bindings/clock/ti/divider.txt @@ -75,6 +75,9 @@ Optional properties: - ti,invert-autoidle-bit : autoidle is enabled by setting the bit to 0, see [2] - ti,set-rate-parent : clk_set_rate is propagated to parent +- ti,latch-bit : latch the divider value to HW, only needed if the register + access requires this. As an example dra76x DPLL_GMAC H14 divider implements + such behavior. Examples: dpll_usb_m2_ck: dpll_usb_m2_ck@4a008190 { diff --git a/Documentation/devicetree/bindings/clock/ti/mux.txt b/Documentation/devicetree/bindings/clock/ti/mux.txt index 2d0d170f8001..eec8994b9be8 100644 --- a/Documentation/devicetree/bindings/clock/ti/mux.txt +++ b/Documentation/devicetree/bindings/clock/ti/mux.txt @@ -48,6 +48,9 @@ Optional properties: zero - ti,set-rate-parent : clk_set_rate is propagated to parent clock, not supported by the composite-mux-clock subtype +- ti,latch-bit : latch the mux value to HW, only needed if the register + access requires this. As an example, dra7x DPLL_GMAC H14 muxing + implements such behavior. Examples: diff --git a/Documentation/devicetree/bindings/crypto/fsl-sec4.txt b/Documentation/devicetree/bindings/crypto/fsl-sec4.txt index 76aec8a3724d..3c1f3a229eab 100644 --- a/Documentation/devicetree/bindings/crypto/fsl-sec4.txt +++ b/Documentation/devicetree/bindings/crypto/fsl-sec4.txt @@ -415,12 +415,27 @@ Secure Non-Volatile Storage (SNVS) Low Power (LP) RTC Node value type: <u32> Definition: LP register offset. default it is 0x34. + - clocks + Usage: optional, required if SNVS LP RTC requires explicit + enablement of clocks + Value type: <prop_encoded-array> + Definition: a clock specifier describing the clock required for + enabling and disabling SNVS LP RTC. + + - clock-names + Usage: optional, required if SNVS LP RTC requires explicit + enablement of clocks + Value type: <string> + Definition: clock name string should be "snvs-rtc". + EXAMPLE sec_mon_rtc_lp@1 { compatible = "fsl,sec-v4.0-mon-rtc-lp"; interrupts = <93 2>; regmap = <&snvs>; offset = <0x34>; + clocks = <&clks IMX7D_SNVS_CLK>; + clock-names = "snvs-rtc"; }; ===================================================================== @@ -543,6 +558,8 @@ FULL EXAMPLE regmap = <&sec_mon>; offset = <0x34>; interrupts = <93 2>; + clocks = <&clks IMX7D_SNVS_CLK>; + clock-names = "snvs-rtc"; }; snvs-pwrkey@020cc000 { diff --git a/Documentation/devicetree/bindings/display/bridge/adi,adv7511.txt b/Documentation/devicetree/bindings/display/bridge/adi,adv7511.txt index 0047b1394c70..2c887536258c 100644 --- a/Documentation/devicetree/bindings/display/bridge/adi,adv7511.txt +++ b/Documentation/devicetree/bindings/display/bridge/adi,adv7511.txt @@ -14,7 +14,13 @@ Required properties: "adi,adv7513" "adi,adv7533" -- reg: I2C slave address +- reg: I2C slave addresses + The ADV7511 internal registers are split into four pages exposed through + different I2C addresses, creating four register maps. Each map has it own + I2C address and acts as a standard slave device on the I2C bus. The main + address is mandatory, others are optional and revert to defaults if not + specified. + The ADV7511 supports a large number of input data formats that differ by their color depth, color format, clock mode, bit justification and random @@ -70,6 +76,9 @@ Optional properties: rather than generate its own timings for HDMI output. - clocks: from common clock binding: reference to the CEC clock. - clock-names: from common clock binding: must be "cec". +- reg-names : Names of maps with programmable addresses. + It can contain any map needing a non-default address. + Possible maps names are : "main", "edid", "cec", "packet" Required nodes: @@ -88,7 +97,12 @@ Example adv7511w: hdmi@39 { compatible = "adi,adv7511w"; - reg = <39>; + /* + * The EDID page will be accessible on address 0x66 on the I2C + * bus. All other maps continue to use their default addresses. + */ + reg = <0x39>, <0x66>; + reg-names = "main", "edid"; interrupt-parent = <&gpio3>; interrupts = <29 IRQ_TYPE_EDGE_FALLING>; clocks = <&cec_clock>; diff --git a/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt new file mode 100644 index 000000000000..f5725bb6c61c --- /dev/null +++ b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt @@ -0,0 +1,133 @@ +Cadence DSI bridge +================== + +The Cadence DSI bridge is a DPI to DSI bridge supporting up to 4 DSI lanes. + +Required properties: +- compatible: should be set to "cdns,dsi". +- reg: physical base address and length of the controller's registers. +- interrupts: interrupt line connected to the DSI bridge. +- clocks: DSI bridge clocks. +- clock-names: must contain "dsi_p_clk" and "dsi_sys_clk". +- phys: phandle link to the MIPI D-PHY controller. +- phy-names: must contain "dphy". +- #address-cells: must be set to 1. +- #size-cells: must be set to 0. + +Optional properties: +- resets: DSI reset lines. +- reset-names: can contain "dsi_p_rst". + +Required subnodes: +- ports: Ports as described in Documentation/devicetree/bindings/graph.txt. + 2 ports are available: + * port 0: this port is only needed if some of your DSI devices are + controlled through an external bus like I2C or SPI. Can have at + most 4 endpoints. The endpoint number is directly encoding the + DSI virtual channel used by this device. + * port 1: represents the DPI input. + Other ports will be added later to support the new kind of inputs. + +- one subnode per DSI device connected on the DSI bus. Each DSI device should + contain a reg property encoding its virtual channel. + +Cadence DPHY +============ + +Cadence DPHY block. + +Required properties: +- compatible: should be set to "cdns,dphy". +- reg: physical base address and length of the DPHY registers. +- clocks: DPHY reference clocks. +- clock-names: must contain "psm" and "pll_ref". +- #phy-cells: must be set to 0. + + +Example: + dphy0: dphy@fd0e0000{ + compatible = "cdns,dphy"; + reg = <0x0 0xfd0e0000 0x0 0x1000>; + clocks = <&psm_clk>, <&pll_ref_clk>; + clock-names = "psm", "pll_ref"; + #phy-cells = <0>; + }; + + dsi0: dsi@fd0c0000 { + compatible = "cdns,dsi"; + reg = <0x0 0xfd0c0000 0x0 0x1000>; + clocks = <&pclk>, <&sysclk>; + clock-names = "dsi_p_clk", "dsi_sys_clk"; + interrupts = <1>; + phys = <&dphy0>; + phy-names = "dphy"; + #address-cells = <1>; + #size-cells = <0>; + + ports { + #address-cells = <1>; + #size-cells = <0>; + + port@1 { + reg = <1>; + dsi0_dpi_input: endpoint { + remote-endpoint = <&xxx_dpi_output>; + }; + }; + }; + + panel: dsi-dev@0 { + compatible = "<vendor,panel>"; + reg = <0>; + }; + }; + +or + + dsi0: dsi@fd0c0000 { + compatible = "cdns,dsi"; + reg = <0x0 0xfd0c0000 0x0 0x1000>; + clocks = <&pclk>, <&sysclk>; + clock-names = "dsi_p_clk", "dsi_sys_clk"; + interrupts = <1>; + phys = <&dphy1>; + phy-names = "dphy"; + #address-cells = <1>; + #size-cells = <0>; + + ports { + #address-cells = <1>; + #size-cells = <0>; + + port@0 { + reg = <0>; + #address-cells = <1>; + #size-cells = <0>; + + dsi0_output: endpoint@0 { + reg = <0>; + remote-endpoint = <&dsi_panel_input>; + }; + }; + + port@1 { + reg = <1>; + dsi0_dpi_input: endpoint { + remote-endpoint = <&xxx_dpi_output>; + }; + }; + }; + }; + + i2c@xxx { + panel: panel@59 { + compatible = "<vendor,panel>"; + reg = <0x59>; + + port { + dsi_panel_input: endpoint { + remote-endpoint = <&dsi0_output>; + }; + }; + }; + }; diff --git a/Documentation/devicetree/bindings/display/bridge/renesas,dw-hdmi.txt b/Documentation/devicetree/bindings/display/bridge/renesas,dw-hdmi.txt index 3a72a103a18a..a41d280c3f9f 100644 --- a/Documentation/devicetree/bindings/display/bridge/renesas,dw-hdmi.txt +++ b/Documentation/devicetree/bindings/display/bridge/renesas,dw-hdmi.txt @@ -14,6 +14,7 @@ Required properties: - compatible : Shall contain one or more of - "renesas,r8a7795-hdmi" for R8A7795 (R-Car H3) compatible HDMI TX - "renesas,r8a7796-hdmi" for R8A7796 (R-Car M3-W) compatible HDMI TX + - "renesas,r8a77965-hdmi" for R8A77965 (R-Car M3-N) compatible HDMI TX - "renesas,rcar-gen3-hdmi" for the generic R-Car Gen3 compatible HDMI TX When compatible with generic versions, nodes must list the SoC-specific diff --git a/Documentation/devicetree/bindings/display/bridge/tda998x.txt b/Documentation/devicetree/bindings/display/bridge/tda998x.txt index 24cc2466185a..1a4eaca40d94 100644 --- a/Documentation/devicetree/bindings/display/bridge/tda998x.txt +++ b/Documentation/devicetree/bindings/display/bridge/tda998x.txt @@ -27,6 +27,9 @@ Optional properties: in question is used. The implementation allows one or two DAIs. If two DAIs are defined, they must be of different type. + - nxp,calib-gpios: calibration GPIO, which must correspond with the + gpio used for the TDA998x interrupt pin. + [1] Documentation/sound/alsa/soc/DAI.txt [2] include/dt-bindings/display/tda998x.h diff --git a/Documentation/devicetree/bindings/display/bridge/thine,thc63lvd1024.txt b/Documentation/devicetree/bindings/display/bridge/thine,thc63lvd1024.txt new file mode 100644 index 000000000000..37f0c04d5a28 --- /dev/null +++ b/Documentation/devicetree/bindings/display/bridge/thine,thc63lvd1024.txt @@ -0,0 +1,60 @@ +Thine Electronics THC63LVD1024 LVDS decoder +------------------------------------------- + +The THC63LVD1024 is a dual link LVDS receiver designed to convert LVDS streams +to parallel data outputs. The chip supports single/dual input/output modes, +handling up to two LVDS input streams and up to two digital CMOS/TTL outputs. + +Single or dual operation mode, output data mapping and DDR output modes are +configured through input signals and the chip does not expose any control bus. + +Required properties: +- compatible: Shall be "thine,thc63lvd1024" +- vcc-supply: Power supply for TTL output, TTL CLOCKOUT signal, LVDS input, + PPL and digital circuitry + +Optional properties: +- powerdown-gpios: Power down GPIO signal, pin name "/PDWN". Active low +- oe-gpios: Output enable GPIO signal, pin name "OE". Active high + +The THC63LVD1024 video port connections are modeled according +to OF graph bindings specified by Documentation/devicetree/bindings/graph.txt + +Required video port nodes: +- port@0: First LVDS input port +- port@2: First digital CMOS/TTL parallel output + +Optional video port nodes: +- port@1: Second LVDS input port +- port@3: Second digital CMOS/TTL parallel output + +Example: +-------- + + thc63lvd1024: lvds-decoder { + compatible = "thine,thc63lvd1024"; + + vcc-supply = <®_lvds_vcc>; + powerdown-gpios = <&gpio4 15 GPIO_ACTIVE_LOW>; + + ports { + #address-cells = <1>; + #size-cells = <0>; + + port@0 { + reg = <0>; + + lvds_dec_in_0: endpoint { + remote-endpoint = <&lvds_out>; + }; + }; + + port@2{ + reg = <2>; + + lvds_dec_out_2: endpoint { + remote-endpoint = <&adv7511_in>; + }; + }; + }; + }; diff --git a/Documentation/devicetree/bindings/display/exynos/exynos5433-decon.txt b/Documentation/devicetree/bindings/display/exynos/exynos5433-decon.txt index fc2588292a68..775193e1c641 100644 --- a/Documentation/devicetree/bindings/display/exynos/exynos5433-decon.txt +++ b/Documentation/devicetree/bindings/display/exynos/exynos5433-decon.txt @@ -19,7 +19,8 @@ Required properties: clock-names property. - clock-names: list of clock names sorted in the same order as the clocks property. Must contain "pclk", "aclk_decon", "aclk_smmu_decon0x", - "aclk_xiu_decon0x", "pclk_smmu_decon0x", clk_decon_vclk", + "aclk_xiu_decon0x", "pclk_smmu_decon0x", "aclk_smmu_decon1x", + "aclk_xiu_decon1x", "pclk_smmu_decon1x", clk_decon_vclk", "sclk_decon_eclk" - ports: contains a port which is connected to mic node. address-cells and size-cells must 1 and 0, respectively. @@ -34,10 +35,14 @@ decon: decon@13800000 { clocks = <&cmu_disp CLK_ACLK_DECON>, <&cmu_disp CLK_ACLK_SMMU_DECON0X>, <&cmu_disp CLK_ACLK_XIU_DECON0X>, <&cmu_disp CLK_PCLK_SMMU_DECON0X>, + <&cmu_disp CLK_ACLK_SMMU_DECON1X>, + <&cmu_disp CLK_ACLK_XIU_DECON1X>, + <&cmu_disp CLK_PCLK_SMMU_DECON1X>, <&cmu_disp CLK_SCLK_DECON_VCLK>, <&cmu_disp CLK_SCLK_DECON_ECLK>; clock-names = "aclk_decon", "aclk_smmu_decon0x", "aclk_xiu_decon0x", - "pclk_smmu_decon0x", "sclk_decon_vclk", "sclk_decon_eclk"; + "pclk_smmu_decon0x", "aclk_smmu_decon1x", "aclk_xiu_decon1x", + "pclk_smmu_decon1x", "sclk_decon_vclk", "sclk_decon_eclk"; interrupt-names = "vsync", "lcd_sys"; interrupts = <0 202 0>, <0 203 0>; diff --git a/Documentation/devicetree/bindings/display/panel/panel-common.txt b/Documentation/devicetree/bindings/display/panel/panel-common.txt index 557fa765adcb..5d2519af4bb5 100644 --- a/Documentation/devicetree/bindings/display/panel/panel-common.txt +++ b/Documentation/devicetree/bindings/display/panel/panel-common.txt @@ -38,7 +38,7 @@ Display Timings require specific display timings. The panel-timing subnode expresses those timings as specified in the timing subnode section of the display timing bindings defined in - Documentation/devicetree/bindings/display/display-timing.txt. + Documentation/devicetree/bindings/display/panel/display-timing.txt. Connectivity diff --git a/Documentation/devicetree/bindings/display/renesas,du.txt b/Documentation/devicetree/bindings/display/renesas,du.txt index c9cd17f99702..7c6854bd0a04 100644 --- a/Documentation/devicetree/bindings/display/renesas,du.txt +++ b/Documentation/devicetree/bindings/display/renesas,du.txt @@ -13,6 +13,7 @@ Required Properties: - "renesas,du-r8a7794" for R8A7794 (R-Car E2) compatible DU - "renesas,du-r8a7795" for R8A7795 (R-Car H3) compatible DU - "renesas,du-r8a7796" for R8A7796 (R-Car M3-W) compatible DU + - "renesas,du-r8a77965" for R8A77965 (R-Car M3-N) compatible DU - "renesas,du-r8a77970" for R8A77970 (R-Car V3M) compatible DU - "renesas,du-r8a77995" for R8A77995 (R-Car D3) compatible DU @@ -47,20 +48,21 @@ bindings specified in Documentation/devicetree/bindings/graph.txt. The following table lists for each supported model the port number corresponding to each DU output. - Port0 Port1 Port2 Port3 + Port0 Port1 Port2 Port3 ----------------------------------------------------------------------------- - R8A7743 (RZ/G1M) DPAD 0 LVDS 0 - - - R8A7745 (RZ/G1E) DPAD 0 DPAD 1 - - - R8A7779 (R-Car H1) DPAD 0 DPAD 1 - - - R8A7790 (R-Car H2) DPAD 0 LVDS 0 LVDS 1 - - R8A7791 (R-Car M2-W) DPAD 0 LVDS 0 - - - R8A7792 (R-Car V2H) DPAD 0 DPAD 1 - - - R8A7793 (R-Car M2-N) DPAD 0 LVDS 0 - - - R8A7794 (R-Car E2) DPAD 0 DPAD 1 - - - R8A7795 (R-Car H3) DPAD 0 HDMI 0 HDMI 1 LVDS 0 - R8A7796 (R-Car M3-W) DPAD 0 HDMI 0 LVDS 0 - - R8A77970 (R-Car V3M) DPAD 0 LVDS 0 - - - R8A77995 (R-Car D3) DPAD 0 LVDS 0 LVDS 1 - + R8A7743 (RZ/G1M) DPAD 0 LVDS 0 - - + R8A7745 (RZ/G1E) DPAD 0 DPAD 1 - - + R8A7779 (R-Car H1) DPAD 0 DPAD 1 - - + R8A7790 (R-Car H2) DPAD 0 LVDS 0 LVDS 1 - + R8A7791 (R-Car M2-W) DPAD 0 LVDS 0 - - + R8A7792 (R-Car V2H) DPAD 0 DPAD 1 - - + R8A7793 (R-Car M2-N) DPAD 0 LVDS 0 - - + R8A7794 (R-Car E2) DPAD 0 DPAD 1 - - + R8A7795 (R-Car H3) DPAD 0 HDMI 0 HDMI 1 LVDS 0 + R8A7796 (R-Car M3-W) DPAD 0 HDMI 0 LVDS 0 - + R8A77965 (R-Car M3-N) DPAD 0 HDMI 0 LVDS 0 - + R8A77970 (R-Car V3M) DPAD 0 LVDS 0 - - + R8A77995 (R-Car D3) DPAD 0 LVDS 0 LVDS 1 - Example: R8A7795 (R-Car H3) ES2.0 DU diff --git a/Documentation/devicetree/bindings/display/sunxi/sun6i-dsi.txt b/Documentation/devicetree/bindings/display/sunxi/sun6i-dsi.txt new file mode 100644 index 000000000000..6a6cf5de08b0 --- /dev/null +++ b/Documentation/devicetree/bindings/display/sunxi/sun6i-dsi.txt @@ -0,0 +1,93 @@ +Allwinner A31 DSI Encoder +========================= + +The DSI pipeline consists of two separate blocks: the DSI controller +itself, and its associated D-PHY. + +DSI Encoder +----------- + +The DSI Encoder generates the DSI signal from the TCON's. + +Required properties: + - compatible: value must be one of: + * allwinner,sun6i-a31-mipi-dsi + - reg: base address and size of memory-mapped region + - interrupts: interrupt associated to this IP + - clocks: phandles to the clocks feeding the DSI encoder + * bus: the DSI interface clock + * mod: the DSI module clock + - clock-names: the clock names mentioned above + - phys: phandle to the D-PHY + - phy-names: must be "dphy" + - resets: phandle to the reset controller driving the encoder + + - ports: A ports node with endpoint definitions as defined in + Documentation/devicetree/bindings/media/video-interfaces.txt. The + first port should be the input endpoint, usually coming from the + associated TCON. + +Any MIPI-DSI device attached to this should be described according to +the bindings defined in ../mipi-dsi-bus.txt + +D-PHY +----- + +Required properties: + - compatible: value must be one of: + * allwinner,sun6i-a31-mipi-dphy + - reg: base address and size of memory-mapped region + - clocks: phandles to the clocks feeding the DSI encoder + * bus: the DSI interface clock + * mod: the DSI module clock + - clock-names: the clock names mentioned above + - resets: phandle to the reset controller driving the encoder + +Example: + +dsi0: dsi@1ca0000 { + compatible = "allwinner,sun6i-a31-mipi-dsi"; + reg = <0x01ca0000 0x1000>; + interrupts = <GIC_SPI 89 IRQ_TYPE_LEVEL_HIGH>; + clocks = <&ccu CLK_BUS_MIPI_DSI>, + <&ccu CLK_DSI_SCLK>; + clock-names = "bus", "mod"; + resets = <&ccu RST_BUS_MIPI_DSI>; + phys = <&dphy0>; + phy-names = "dphy"; + #address-cells = <1>; + #size-cells = <0>; + + panel@0 { + compatible = "bananapi,lhr050h41", "ilitek,ili9881c"; + reg = <0>; + power-gpios = <&pio 1 7 GPIO_ACTIVE_HIGH>; /* PB07 */ + reset-gpios = <&r_pio 0 5 GPIO_ACTIVE_LOW>; /* PL05 */ + backlight = <&pwm_bl>; + }; + + ports { + #address-cells = <1>; + #size-cells = <0>; + + port@0 { + #address-cells = <1>; + #size-cells = <0>; + reg = <0>; + + dsi0_in_tcon0: endpoint { + remote-endpoint = <&tcon0_out_dsi0>; + }; + }; + }; +}; + +dphy0: d-phy@1ca1000 { + compatible = "allwinner,sun6i-a31-mipi-dphy"; + reg = <0x01ca1000 0x1000>; + clocks = <&ccu CLK_BUS_MIPI_DSI>, + <&ccu CLK_DSI_DPHY>; + clock-names = "bus", "mod"; + resets = <&ccu RST_BUS_MIPI_DSI>; + #phy-cells = <0>; +}; diff --git a/Documentation/devicetree/bindings/dma/brcm,bcm2835-dma.txt b/Documentation/devicetree/bindings/dma/brcm,bcm2835-dma.txt index baf9b34d20bf..b6a8cc0978cd 100644 --- a/Documentation/devicetree/bindings/dma/brcm,bcm2835-dma.txt +++ b/Documentation/devicetree/bindings/dma/brcm,bcm2835-dma.txt @@ -74,8 +74,8 @@ Example: bcm2835_i2s: i2s@7e203000 { compatible = "brcm,bcm2835-i2s"; - reg = < 0x7e203000 0x20>, - < 0x7e101098 0x02>; + reg = < 0x7e203000 0x24>; + clocks = <&clocks BCM2835_CLOCK_PCM>; dmas = <&dma 2>, <&dma 3>; diff --git a/Documentation/devicetree/bindings/dma/mtk-hsdma.txt b/Documentation/devicetree/bindings/dma/mtk-hsdma.txt new file mode 100644 index 000000000000..4bb317359dc6 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/mtk-hsdma.txt @@ -0,0 +1,33 @@ +MediaTek High-Speed DMA Controller +================================== + +This device follows the generic DMA bindings defined in dma/dma.txt. + +Required properties: + +- compatible: Must be one of + "mediatek,mt7622-hsdma": for MT7622 SoC + "mediatek,mt7623-hsdma": for MT7623 SoC +- reg: Should contain the register's base address and length. +- interrupts: Should contain a reference to the interrupt used by this + device. +- clocks: Should be the clock specifiers corresponding to the entry in + clock-names property. +- clock-names: Should contain "hsdma" entries. +- power-domains: Phandle to the power domain that the device is part of +- #dma-cells: The length of the DMA specifier, must be <1>. This one cell + in dmas property of a client device represents the channel + number. +Example: + + hsdma: dma-controller@1b007000 { + compatible = "mediatek,mt7623-hsdma"; + reg = <0 0x1b007000 0 0x1000>; + interrupts = <GIC_SPI 98 IRQ_TYPE_LEVEL_LOW>; + clocks = <ðsys CLK_ETHSYS_HSDMA>; + clock-names = "hsdma"; + power-domains = <&scpsys MT2701_POWER_DOMAIN_ETH>; + #dma-cells = <1>; + }; + +DMA clients must use the format described in dma/dma.txt file. diff --git a/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt b/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt index 9cbf5d9df8fd..cf5b9e44432c 100644 --- a/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt +++ b/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt @@ -15,6 +15,10 @@ Required properties: the secure world. - qcom,controlled-remotely : optional, indicates that the bam is controlled by remote proccessor i.e. execution environment. +- num-channels : optional, indicates supported number of DMA channels in a + remotely controlled bam. +- qcom,num-ees : optional, indicates supported number of Execution Environments + in a remotely controlled bam. Example: diff --git a/Documentation/devicetree/bindings/dma/renesas,rcar-dmac.txt b/Documentation/devicetree/bindings/dma/renesas,rcar-dmac.txt index 891db41e9420..61315eaa7660 100644 --- a/Documentation/devicetree/bindings/dma/renesas,rcar-dmac.txt +++ b/Documentation/devicetree/bindings/dma/renesas,rcar-dmac.txt @@ -18,6 +18,7 @@ Required Properties: Examples with soctypes are: - "renesas,dmac-r8a7743" (RZ/G1M) - "renesas,dmac-r8a7745" (RZ/G1E) + - "renesas,dmac-r8a77470" (RZ/G1C) - "renesas,dmac-r8a7790" (R-Car H2) - "renesas,dmac-r8a7791" (R-Car M2-W) - "renesas,dmac-r8a7792" (R-Car V2H) @@ -25,7 +26,9 @@ Required Properties: - "renesas,dmac-r8a7794" (R-Car E2) - "renesas,dmac-r8a7795" (R-Car H3) - "renesas,dmac-r8a7796" (R-Car M3-W) + - "renesas,dmac-r8a77965" (R-Car M3-N) - "renesas,dmac-r8a77970" (R-Car V3M) + - "renesas,dmac-r8a77980" (R-Car V3H) - reg: base address and length of the registers block for the DMAC diff --git a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt index f3d1f151ba80..9dc935e24e55 100644 --- a/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt +++ b/Documentation/devicetree/bindings/dma/renesas,usb-dmac.txt @@ -11,6 +11,7 @@ Required Properties: - "renesas,r8a7794-usb-dmac" (R-Car E2) - "renesas,r8a7795-usb-dmac" (R-Car H3) - "renesas,r8a7796-usb-dmac" (R-Car M3-W) + - "renesas,r8a77965-usb-dmac" (R-Car M3-N) - reg: base address and length of the registers block for the DMAC - interrupts: interrupt specifiers for the DMAC, one for each entry in interrupt-names. diff --git a/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.txt b/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.txt new file mode 100644 index 000000000000..f237b7928283 --- /dev/null +++ b/Documentation/devicetree/bindings/dma/snps,dw-axi-dmac.txt @@ -0,0 +1,41 @@ +Synopsys DesignWare AXI DMA Controller + +Required properties: +- compatible: "snps,axi-dma-1.01a" +- reg: Address range of the DMAC registers. This should include + all of the per-channel registers. +- interrupt: Should contain the DMAC interrupt number. +- interrupt-parent: Should be the phandle for the interrupt controller + that services interrupts for this device. +- dma-channels: Number of channels supported by hardware. +- snps,dma-masters: Number of AXI masters supported by the hardware. +- snps,data-width: Maximum AXI data width supported by hardware. + (0 - 8bits, 1 - 16bits, 2 - 32bits, ..., 6 - 512bits) +- snps,priority: Priority of channel. Array size is equal to the number of + dma-channels. Priority value must be programmed within [0:dma-channels-1] + range. (0 - minimum priority) +- snps,block-size: Maximum block size supported by the controller channel. + Array size is equal to the number of dma-channels. + +Optional properties: +- snps,axi-max-burst-len: Restrict master AXI burst length by value specified + in this property. If this property is missing the maximum AXI burst length + supported by DMAC is used. [1:256] + +Example: + +dmac: dma-controller@80000 { + compatible = "snps,axi-dma-1.01a"; + reg = <0x80000 0x400>; + clocks = <&core_clk>, <&cfgr_clk>; + clock-names = "core-clk", "cfgr-clk"; + interrupt-parent = <&intc>; + interrupts = <27>; + + dma-channels = <4>; + snps,dma-masters = <2>; + snps,data-width = <3>; + snps,block-size = <4096 4096 4096 4096>; + snps,priority = <0 1 2 3>; + snps,axi-max-burst-len = <16>; +}; diff --git a/Documentation/devicetree/bindings/dma/stm32-dma.txt b/Documentation/devicetree/bindings/dma/stm32-dma.txt index 0b55718bf889..c5f519097204 100644 --- a/Documentation/devicetree/bindings/dma/stm32-dma.txt +++ b/Documentation/devicetree/bindings/dma/stm32-dma.txt @@ -62,14 +62,14 @@ channel: a phandle to the DMA controller plus the following four integer cells: 0x1: medium 0x2: high 0x3: very high -4. A 32bit mask specifying the DMA FIFO threshold configuration which are device - dependent: - -bit 0-1: Fifo threshold +4. A 32bit bitfield value specifying DMA features which are device dependent: + -bit 0-1: DMA FIFO threshold selection 0x0: 1/4 full FIFO 0x1: 1/2 full FIFO 0x2: 3/4 full FIFO 0x3: full FIFO + Example: usart1: serial@40011000 { diff --git a/Documentation/devicetree/bindings/arm/altera/socfpga-eccmgr.txt b/Documentation/devicetree/bindings/edac/socfpga-eccmgr.txt index 4a1714f96bab..5626560a6cfd 100644 --- a/Documentation/devicetree/bindings/arm/altera/socfpga-eccmgr.txt +++ b/Documentation/devicetree/bindings/edac/socfpga-eccmgr.txt @@ -231,3 +231,38 @@ Example: <48 IRQ_TYPE_LEVEL_HIGH>; }; }; + +Stratix10 SoCFPGA ECC Manager +The Stratix10 SoC ECC Manager handles the IRQs for each peripheral +in a shared register similar to the Arria10. However, ECC requires +access to registers that can only be read from Secure Monitor with +SMC calls. Therefore the device tree is slightly different. + +Required Properties: +- compatible : Should be "altr,socfpga-s10-ecc-manager" +- interrupts : Should be single bit error interrupt, then double bit error + interrupt. +- interrupt-controller : boolean indicator that ECC Manager is an interrupt controller +- #interrupt-cells : must be set to 2. + +Subcomponents: + +SDRAM ECC +Required Properties: +- compatible : Should be "altr,sdram-edac-s10" +- interrupts : Should be single bit error interrupt, then double bit error + interrupt, in this order. + +Example: + + eccmgr { + compatible = "altr,socfpga-s10-ecc-manager"; + interrupts = <0 15 4>, <0 95 4>; + interrupt-controller; + #interrupt-cells = <2>; + + sdramedac { + compatible = "altr,sdram-edac-s10"; + interrupts = <16 4>, <48 4>; + }; + }; diff --git a/Documentation/devicetree/bindings/eeprom/at24.txt b/Documentation/devicetree/bindings/eeprom/at24.txt index abfae1beca2b..61d833abafbf 100644 --- a/Documentation/devicetree/bindings/eeprom/at24.txt +++ b/Documentation/devicetree/bindings/eeprom/at24.txt @@ -41,12 +41,16 @@ Required properties: "nxp", "ramtron", "renesas", + "rohm", "st", Some vendors use different model names for chips which are just variants of the above. Known such exceptions are listed below: + "nxp,se97b" - the fallback is "atmel,24c02", "renesas,r1ex24002" - the fallback is "atmel,24c02" + "renesas,r1ex24128" - the fallback is "atmel,24c128" + "rohm,br24t01" - the fallback is "atmel,24c01" - reg: The I2C address of the EEPROM. diff --git a/Documentation/devicetree/bindings/fpga/lattice-machxo2-spi.txt b/Documentation/devicetree/bindings/fpga/lattice-machxo2-spi.txt new file mode 100644 index 000000000000..a8c362eb160c --- /dev/null +++ b/Documentation/devicetree/bindings/fpga/lattice-machxo2-spi.txt @@ -0,0 +1,29 @@ +Lattice MachXO2 Slave SPI FPGA Manager + +Lattice MachXO2 FPGAs support a method of loading the bitstream over +'slave SPI' interface. + +See 'MachXO2ProgrammingandConfigurationUsageGuide.pdf' on www.latticesemi.com + +Required properties: +- compatible: should contain "lattice,machxo2-slave-spi" +- reg: spi chip select of the FPGA + +Example for full FPGA configuration: + + fpga-region0 { + compatible = "fpga-region"; + fpga-mgr = <&fpga_mgr_spi>; + #address-cells = <0x1>; + #size-cells = <0x1>; + }; + + spi1: spi@2000 { + ... + + fpga_mgr_spi: fpga-mgr@0 { + compatible = "lattice,machxo2-slave-spi"; + spi-max-frequency = <8000000>; + reg = <0>; + }; + }; diff --git a/Documentation/devicetree/bindings/gpu/arm,mali-utgard.txt b/Documentation/devicetree/bindings/gpu/arm,mali-utgard.txt index ad876548ab5d..c1f65d1dac1d 100644 --- a/Documentation/devicetree/bindings/gpu/arm,mali-utgard.txt +++ b/Documentation/devicetree/bindings/gpu/arm,mali-utgard.txt @@ -10,6 +10,7 @@ Required properties: * And, optionally, one of the vendor specific compatible: + allwinner,sun4i-a10-mali + allwinner,sun7i-a20-mali + + allwinner,sun8i-h3-mali + allwinner,sun50i-h5-mali + amlogic,meson-gxbb-mali + amlogic,meson-gxl-mali diff --git a/Documentation/devicetree/bindings/gpu/brcm,bcm-v3d.txt b/Documentation/devicetree/bindings/gpu/brcm,bcm-v3d.txt new file mode 100644 index 000000000000..c907aa8dd755 --- /dev/null +++ b/Documentation/devicetree/bindings/gpu/brcm,bcm-v3d.txt @@ -0,0 +1,28 @@ +Broadcom V3D GPU + +Only the Broadcom V3D 3.x and newer GPUs are covered by this binding. +For V3D 2.x, see brcm,bcm-vc4.txt. + +Required properties: +- compatible: Should be "brcm,7268-v3d" or "brcm,7278-v3d" +- reg: Physical base addresses and lengths of the register areas +- reg-names: Names for the register areas. The "hub", "bridge", and "core0" + register areas are always required. The "gca" register area + is required if the GCA cache controller is present. +- interrupts: The interrupt numbers. The first interrupt is for the hub, + while the following interrupts are for the cores. + See bindings/interrupt-controller/interrupts.txt + +Optional properties: +- clocks: The core clock the unit runs on + +v3d { + compatible = "brcm,7268-v3d"; + reg = <0xf1204000 0x100>, + <0xf1200000 0x4000>, + <0xf1208000 0x4000>, + <0xf1204100 0x100>; + reg-names = "bridge", "hub", "core0", "gca"; + interrupts = <0 78 4>, + <0 77 4>; +}; diff --git a/Documentation/devicetree/bindings/gpu/samsung-scaler.txt b/Documentation/devicetree/bindings/gpu/samsung-scaler.txt new file mode 100644 index 000000000000..9c3d98105dfd --- /dev/null +++ b/Documentation/devicetree/bindings/gpu/samsung-scaler.txt @@ -0,0 +1,27 @@ +* Samsung Exynos Image Scaler + +Required properties: + - compatible : value should be one of the following: + (a) "samsung,exynos5420-scaler" for Scaler IP in Exynos5420 + (b) "samsung,exynos5433-scaler" for Scaler IP in Exynos5433 + + - reg : Physical base address of the IP registers and length of memory + mapped region. + + - interrupts : Interrupt specifier for scaler interrupt, according to format + specific to interrupt parent. + + - clocks : Clock specifier for scaler clock, according to generic clock + bindings. (See Documentation/devicetree/bindings/clock/exynos*.txt) + + - clock-names : Names of clocks. For exynos scaler, it should be "mscl" + on 5420 and "pclk", "aclk" and "aclk_xiu" on 5433. + +Example: + scaler@12800000 { + compatible = "samsung,exynos5420-scaler"; + reg = <0x12800000 0x1294>; + interrupts = <0 220 IRQ_TYPE_LEVEL_HIGH>; + clocks = <&clock CLK_MSCL0>; + clock-names = "mscl"; + }; diff --git a/Documentation/devicetree/bindings/hwmon/gpio-fan.txt b/Documentation/devicetree/bindings/hwmon/gpio-fan.txt index 439a7430fc68..2becdcfdc840 100644 --- a/Documentation/devicetree/bindings/hwmon/gpio-fan.txt +++ b/Documentation/devicetree/bindings/hwmon/gpio-fan.txt @@ -11,7 +11,7 @@ Optional properties: must have the RPM values in ascending order. - alarm-gpios: This pin going active indicates something is wrong with the fan, and a udev event will be fired. -- cooling-cells: If used as a cooling device, must be <2> +- #cooling-cells: If used as a cooling device, must be <2> Also see: Documentation/devicetree/bindings/thermal/thermal.txt min and max states are derived from the speed-map of the fan. diff --git a/Documentation/devicetree/bindings/hwmon/ltc2990.txt b/Documentation/devicetree/bindings/hwmon/ltc2990.txt new file mode 100644 index 000000000000..f92f54029e84 --- /dev/null +++ b/Documentation/devicetree/bindings/hwmon/ltc2990.txt @@ -0,0 +1,36 @@ +ltc2990: Linear Technology LTC2990 power monitor + +Required properties: +- compatible: Must be "lltc,ltc2990" +- reg: I2C slave address +- lltc,meas-mode: + An array of two integers for configuring the chip measurement mode. + + The first integer defines the bits 2..0 in the control register. In all + cases the internal temperature and supply voltage are measured. In + addition the following input measurements are enabled per mode: + + 0: V1, V2, TR2 + 1: V1-V2, TR2 + 2: V1-V2, V3, V4 + 3: TR1, V3, V4 + 4: TR1, V3-V4 + 5: TR1, TR2 + 6: V1-V2, V3-V4 + 7: V1, V2, V3, V4 + + The second integer defines the bits 4..3 in the control register. This + allows a subset of the measurements to be enabled: + + 0: Internal temperature and supply voltage only + 1: TR1, V1 or V1-V2 only per mode + 2: TR2, V3 or V3-V4 only per mode + 3: All measurements per mode + +Example: + +ltc2990@4c { + compatible = "lltc,ltc2990"; + reg = <0x4c>; + lltc,meas-mode = <7 3>; /* V1, V2, V3, V4 */ +}; diff --git a/Documentation/devicetree/bindings/i2c/i2c-rcar.txt b/Documentation/devicetree/bindings/i2c/i2c-rcar.txt index a777477e4547..4a7811ecd954 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-rcar.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-rcar.txt @@ -13,7 +13,9 @@ Required properties: "renesas,i2c-r8a7794" if the device is a part of a R8A7794 SoC. "renesas,i2c-r8a7795" if the device is a part of a R8A7795 SoC. "renesas,i2c-r8a7796" if the device is a part of a R8A7796 SoC. + "renesas,i2c-r8a77965" if the device is a part of a R8A77965 SoC. "renesas,i2c-r8a77970" if the device is a part of a R8A77970 SoC. + "renesas,i2c-r8a77995" if the device is a part of a R8A77995 SoC. "renesas,rcar-gen1-i2c" for a generic R-Car Gen1 compatible device. "renesas,rcar-gen2-i2c" for a generic R-Car Gen2 or RZ/G1 compatible device. diff --git a/Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt b/Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt index 224390999e81..fc7e17802746 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt @@ -13,6 +13,7 @@ Required properties: - "renesas,iic-r8a7794" (R-Car E2) - "renesas,iic-r8a7795" (R-Car H3) - "renesas,iic-r8a7796" (R-Car M3-W) + - "renesas,iic-r8a77965" (R-Car M3-N) - "renesas,iic-sh73a0" (SH-Mobile AG5) - "renesas,rcar-gen2-iic" (generic R-Car Gen2 or RZ/G1 compatible device) diff --git a/Documentation/devicetree/bindings/i2c/i2c-synquacer.txt b/Documentation/devicetree/bindings/i2c/i2c-synquacer.txt new file mode 100644 index 000000000000..72f4a2f0fedc --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c-synquacer.txt @@ -0,0 +1,29 @@ +Socionext SynQuacer I2C + +Required properties: +- compatible : Must be "socionext,synquacer-i2c" +- reg : Offset and length of the register set for the device +- interrupts : A single interrupt specifier +- #address-cells : Must be <1>; +- #size-cells : Must be <0>; +- clock-names : Must contain "pclk". +- clocks : Must contain an entry for each name in clock-names. + (See the common clock bindings.) + +Optional properties: +- clock-frequency : Desired I2C bus clock frequency in Hz. As only Normal and + Fast modes are supported, possible values are 100000 and + 400000. + +Example : + + i2c@51210000 { + compatible = "socionext,synquacer-i2c"; + reg = <0x51210000 0x1000>; + interrupts = <GIC_SPI 165 IRQ_TYPE_LEVEL_HIGH>; + #address-cells = <1>; + #size-cells = <0>; + clock-names = "pclk"; + clocks = <&clk_i2c>; + clock-frequency = <400000>; + }; diff --git a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt index 23e3abc3fdef..c88919480d37 100644 --- a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt +++ b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt @@ -4,6 +4,13 @@ Required properties: - compatible: atmel,maxtouch + The following compatibles have been used in various products but are + deprecated: + atmel,qt602240_ts + atmel,atmel_mxt_ts + atmel,atmel_mxt_tp + atmel,mXT224 + - reg: The I2C address of the device - interrupts: The sink for the touchpad's IRQ output diff --git a/Documentation/devicetree/bindings/input/elan_i2c.txt b/Documentation/devicetree/bindings/input/elan_i2c.txt index ee3242c4ba67..d80a83583238 100644 --- a/Documentation/devicetree/bindings/input/elan_i2c.txt +++ b/Documentation/devicetree/bindings/input/elan_i2c.txt @@ -14,6 +14,7 @@ Optional properties: - pinctrl-0: a phandle pointing to the pin settings for the device (see pinctrl binding [1]). - vcc-supply: a phandle for the regulator supplying 3.3V power. +- elan,trackpoint: touchpad can support a trackpoint (boolean) [0]: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt [1]: Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt diff --git a/Documentation/devicetree/bindings/interrupt-controller/amlogic,meson-gpio-intc.txt b/Documentation/devicetree/bindings/interrupt-controller/amlogic,meson-gpio-intc.txt index a83f9a5734ca..89674ad8a097 100644 --- a/Documentation/devicetree/bindings/interrupt-controller/amlogic,meson-gpio-intc.txt +++ b/Documentation/devicetree/bindings/interrupt-controller/amlogic,meson-gpio-intc.txt @@ -9,11 +9,12 @@ number of interrupt exposed depends on the SoC. Required properties: -- compatible : must have "amlogic,meson8-gpio-intc” and either - “amlogic,meson8-gpio-intc” for meson8 SoCs (S802) or - “amlogic,meson8b-gpio-intc” for meson8b SoCs (S805) or - “amlogic,meson-gxbb-gpio-intc” for GXBB SoCs (S905) or - “amlogic,meson-gxl-gpio-intc” for GXL SoCs (S905X, S912) +- compatible : must have "amlogic,meson8-gpio-intc" and either + "amlogic,meson8-gpio-intc" for meson8 SoCs (S802) or + "amlogic,meson8b-gpio-intc" for meson8b SoCs (S805) or + "amlogic,meson-gxbb-gpio-intc" for GXBB SoCs (S905) or + "amlogic,meson-gxl-gpio-intc" for GXL SoCs (S905X, S912) + "amlogic,meson-axg-gpio-intc" for AXG SoCs (A113D, A113X) - interrupt-parent : a phandle to the GIC the interrupts are routed to. Usually this is provided at the root level of the device tree as it is common to most of the SoC. diff --git a/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt b/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt index 0a57f2f4167d..3ea78c4ef887 100644 --- a/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt +++ b/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt @@ -57,6 +57,20 @@ Optional occupied by the redistributors. Required if more than one such region is present. +- msi-controller: Boolean property. Identifies the node as an MSI + controller. Only present if the Message Based Interrupt + functionnality is being exposed by the HW, and the mbi-ranges + property present. + +- mbi-ranges: A list of pairs <intid span>, where "intid" is the first + SPI of a range that can be used an MBI, and "span" the size of that + range. Multiple ranges can be provided. Requires "msi-controller" to + be set. + +- mbi-alias: Address property. Base address of an alias of the GICD + region containing only the {SET,CLR}SPI registers to be used if + isolation is required, and if supported by the HW. + Sub-nodes: PPI affinity can be expressed as a single "ppi-partitions" node, @@ -99,6 +113,9 @@ Examples: <0x0 0x2c020000 0 0x2000>; // GICV interrupts = <1 9 4>; + msi-controller; + mbi-ranges = <256 128>; + gic-its@2c200000 { compatible = "arm,gic-v3-its"; msi-controller; diff --git a/Documentation/devicetree/bindings/interrupt-controller/st,stm32-exti.txt b/Documentation/devicetree/bindings/interrupt-controller/st,stm32-exti.txt index edf03f09244b..136bd612bd83 100644 --- a/Documentation/devicetree/bindings/interrupt-controller/st,stm32-exti.txt +++ b/Documentation/devicetree/bindings/interrupt-controller/st,stm32-exti.txt @@ -5,11 +5,14 @@ Required properties: - compatible: Should be: "st,stm32-exti" "st,stm32h7-exti" + "st,stm32mp1-exti" - reg: Specifies base physical address and size of the registers - interrupt-controller: Indentifies the node as an interrupt controller - #interrupt-cells: Specifies the number of cells to encode an interrupt specifier, shall be 2 - interrupts: interrupts references to primary interrupt controller + (only needed for exti controller with multiple exti under + same parent interrupt: st,stm32-exti and st,stm32h7-exti") Example: diff --git a/Documentation/devicetree/bindings/iommu/renesas,ipmmu-vmsa.txt b/Documentation/devicetree/bindings/iommu/renesas,ipmmu-vmsa.txt index 1fd5d69647ca..ffadb7c6f1f3 100644 --- a/Documentation/devicetree/bindings/iommu/renesas,ipmmu-vmsa.txt +++ b/Documentation/devicetree/bindings/iommu/renesas,ipmmu-vmsa.txt @@ -11,6 +11,8 @@ Required Properties: the device is compatible with the R-Car Gen2 VMSA-compatible IPMMU. - "renesas,ipmmu-r8a73a4" for the R8A73A4 (R-Mobile APE6) IPMMU. + - "renesas,ipmmu-r8a7743" for the R8A7743 (RZ/G1M) IPMMU. + - "renesas,ipmmu-r8a7745" for the R8A7745 (RZ/G1E) IPMMU. - "renesas,ipmmu-r8a7790" for the R8A7790 (R-Car H2) IPMMU. - "renesas,ipmmu-r8a7791" for the R8A7791 (R-Car M2-W) IPMMU. - "renesas,ipmmu-r8a7793" for the R8A7793 (R-Car M2-N) IPMMU. @@ -19,7 +21,8 @@ Required Properties: - "renesas,ipmmu-r8a7796" for the R8A7796 (R-Car M3-W) IPMMU. - "renesas,ipmmu-r8a77970" for the R8A77970 (R-Car V3M) IPMMU. - "renesas,ipmmu-r8a77995" for the R8A77995 (R-Car D3) IPMMU. - - "renesas,ipmmu-vmsa" for generic R-Car Gen2 VMSA-compatible IPMMU. + - "renesas,ipmmu-vmsa" for generic R-Car Gen2 or RZ/G1 VMSA-compatible + IPMMU. - reg: Base address and size of the IPMMU registers. - interrupts: Specifiers for the MMU fault interrupts. For instances that diff --git a/Documentation/devicetree/bindings/iommu/rockchip,iommu.txt b/Documentation/devicetree/bindings/iommu/rockchip,iommu.txt index 2098f7732264..6ecefea1c6f9 100644 --- a/Documentation/devicetree/bindings/iommu/rockchip,iommu.txt +++ b/Documentation/devicetree/bindings/iommu/rockchip,iommu.txt @@ -14,6 +14,11 @@ Required properties: "single-master" device, and needs no additional information to associate with its master device. See: Documentation/devicetree/bindings/iommu/iommu.txt +- clocks : A list of clocks required for the IOMMU to be accessible by + the host CPU. +- clock-names : Should contain the following: + "iface" - Main peripheral bus clock (PCLK/HCL) (required) + "aclk" - AXI bus clock (required) Optional properties: - rockchip,disable-mmu-reset : Don't use the mmu reset operation. @@ -27,5 +32,7 @@ Example: reg = <0xff940300 0x100>; interrupts = <GIC_SPI 16 IRQ_TYPE_LEVEL_HIGH>; interrupt-names = "vopl_mmu"; + clocks = <&cru ACLK_VOP1>, <&cru HCLK_VOP1>; + clock-names = "aclk", "iface"; #iommu-cells = <0>; }; diff --git a/Documentation/devicetree/bindings/ipmi/npcm7xx-kcs-bmc.txt b/Documentation/devicetree/bindings/ipmi/npcm7xx-kcs-bmc.txt new file mode 100644 index 000000000000..3538a214fff1 --- /dev/null +++ b/Documentation/devicetree/bindings/ipmi/npcm7xx-kcs-bmc.txt @@ -0,0 +1,39 @@ +* Nuvoton NPCM7xx KCS (Keyboard Controller Style) IPMI interface + +The Nuvoton SOCs (NPCM7xx) are commonly used as BMCs +(Baseboard Management Controllers) and the KCS interface can be +used to perform in-band IPMI communication with their host. + +Required properties: +- compatible : should be one of + "nuvoton,npcm750-kcs-bmc" +- interrupts : interrupt generated by the controller +- kcs_chan : The KCS channel number in the controller + +Example: + + lpc_kcs: lpc_kcs@f0007000 { + compatible = "nuvoton,npcm750-lpc-kcs", "simple-mfd", "syscon"; + reg = <0xf0007000 0x40>; + reg-io-width = <1>; + + #address-cells = <1>; + #size-cells = <1>; + ranges = <0x0 0xf0007000 0x40>; + + kcs1: kcs1@0 { + compatible = "nuvoton,npcm750-kcs-bmc"; + reg = <0x0 0x40>; + interrupts = <0 9 4>; + kcs_chan = <1>; + status = "disabled"; + }; + + kcs2: kcs2@0 { + compatible = "nuvoton,npcm750-kcs-bmc"; + reg = <0x0 0x40>; + interrupts = <0 9 4>; + kcs_chan = <2>; + status = "disabled"; + }; + };
\ No newline at end of file diff --git a/Documentation/devicetree/bindings/leds/leds-cr0014114.txt b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt new file mode 100644 index 000000000000..4255b19ad25c --- /dev/null +++ b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt @@ -0,0 +1,54 @@ +Crane Merchandising System - cr0014114 LED driver +------------------------------------------------- + +This LED Board is widely used in vending machines produced +by Crane Merchandising Systems. + +Required properties: +- compatible: "crane,cr0014114" + +Property rules described in Documentation/devicetree/bindings/spi/spi-bus.txt +apply. In particular, "reg" and "spi-max-frequency" properties must be given. + +LED sub-node properties: +- label : + see Documentation/devicetree/bindings/leds/common.txt +- linux,default-trigger : (optional) + see Documentation/devicetree/bindings/leds/common.txt + +Example +------- + +led-controller@0 { + compatible = "crane,cr0014114"; + reg = <0>; + spi-max-frequency = <50000>; + #address-cells = <1>; + #size-cells = <0>; + + led@0 { + reg = <0>; + label = "red:coin"; + }; + led@1 { + reg = <1>; + label = "green:coin"; + }; + led@2 { + reg = <2>; + label = "blue:coin"; + }; + led@3 { + reg = <3>; + label = "red:bill"; + }; + led@4 { + reg = <4>; + label = "green:bill"; + }; + led@5 { + reg = <5>; + label = "blue:bill"; + }; + ... +}; diff --git a/Documentation/devicetree/bindings/leds/leds-lm3601x.txt b/Documentation/devicetree/bindings/leds/leds-lm3601x.txt new file mode 100644 index 000000000000..a88b2c41e75b --- /dev/null +++ b/Documentation/devicetree/bindings/leds/leds-lm3601x.txt @@ -0,0 +1,45 @@ +* Texas Instruments - lm3601x Single-LED Flash Driver + +The LM3601X are ultra-small LED flash drivers that +provide a high level of adjustability. + +Required properties: + - compatible : Can be one of the following + "ti,lm36010" + "ti,lm36011" + - reg : I2C slave address + - #address-cells : 1 + - #size-cells : 0 + +Required child properties: + - reg : 0 - Indicates a IR mode + 1 - Indicates a Torch (white LED) mode + +Required properties for flash LED child nodes: + See Documentation/devicetree/bindings/leds/common.txt + - flash-max-microamp : Range from 11mA - 1.5A + - flash-max-timeout-us : Range from 40ms - 1600ms + - led-max-microamp : Range from 2.4mA - 376mA + +Optional child properties: + - label : see Documentation/devicetree/bindings/leds/common.txt + +Example: +led-controller@64 { + compatible = "ti,lm36010"; + #address-cells = <1>; + #size-cells = <0>; + reg = <0x64>; + + led@0 { + reg = <1>; + label = "white:torch"; + led-max-microamp = <376000>; + flash-max-microamp = <1500000>; + flash-max-timeout-us = <1600000>; + }; +} + +For more product information please see the links below: +http://www.ti.com/product/LM36010 +http://www.ti.com/product/LM36011 diff --git a/Documentation/devicetree/bindings/leds/leds-sc27xx-bltc.txt b/Documentation/devicetree/bindings/leds/leds-sc27xx-bltc.txt new file mode 100644 index 000000000000..dddf84f9c7ea --- /dev/null +++ b/Documentation/devicetree/bindings/leds/leds-sc27xx-bltc.txt @@ -0,0 +1,41 @@ +LEDs connected to Spreadtrum SC27XX PMIC breathing light controller + +The SC27xx breathing light controller supports to 3 outputs: +red LED, green LED and blue LED. Each LED can work at normal +PWM mode or breath light mode. + +Required properties: +- compatible: Should be "sprd,sc2731-bltc". +- #address-cells: Must be 1. +- #size-cells: Must be 0. +- reg: Specify the controller address. + +Required child properties: +- reg: Port this LED is connected to. + +Optional child properties: +- label: See Documentation/devicetree/bindings/leds/common.txt. + +Examples: + +led-controller@200 { + compatible = "sprd,sc2731-bltc"; + #address-cells = <1>; + #size-cells = <0>; + reg = <0x200>; + + led@0 { + label = "red"; + reg = <0x0>; + }; + + led@1 { + label = "green"; + reg = <0x1>; + }; + + led@2 { + label = "blue"; + reg = <0x2>; + }; +}; diff --git a/Documentation/devicetree/bindings/mailbox/hisilicon,hi3660-mailbox.txt b/Documentation/devicetree/bindings/mailbox/hisilicon,hi3660-mailbox.txt new file mode 100644 index 000000000000..3e5b4537407d --- /dev/null +++ b/Documentation/devicetree/bindings/mailbox/hisilicon,hi3660-mailbox.txt @@ -0,0 +1,51 @@ +Hisilicon Hi3660 Mailbox Controller + +Hisilicon Hi3660 mailbox controller supports up to 32 channels. Messages +are passed between processors, including application & communication +processors, MCU, HIFI, etc. Each channel is unidirectional and accessed +by using MMIO registers; it supports maximum to 8 words message. + +Controller +---------- + +Required properties: +- compatible: : Shall be "hisilicon,hi3660-mbox" +- reg: : Offset and length of the device's register set +- #mbox-cells: : Must be 3 + <&phandle channel dst_irq ack_irq> + phandle : Label name of controller + channel : Channel number + dst_irq : Remote interrupt vector + ack_irq : Local interrupt vector + +- interrupts: : Contains the two IRQ lines for mailbox. + +Example: + +mailbox: mailbox@e896b000 { + compatible = "hisilicon,hi3660-mbox"; + reg = <0x0 0xe896b000 0x0 0x1000>; + interrupts = <0x0 0xc0 0x4>, + <0x0 0xc1 0x4>; + #mbox-cells = <3>; +}; + +Client +------ + +Required properties: +- compatible : See the client docs +- mboxes : Standard property to specify a Mailbox (See ./mailbox.txt) + Cells must match 'mbox-cells' (See Controller docs above) + +Optional properties +- mbox-names : Name given to channels seen in the 'mboxes' property. + +Example: + +stub_clock: stub_clock@e896b500 { + compatible = "hisilicon,hi3660-stub-clk"; + reg = <0x0 0xe896b500 0x0 0x0100>; + #clock-cells = <1>; + mboxes = <&mailbox 13 3 0>; +}; diff --git a/Documentation/devicetree/bindings/mailbox/mailbox.txt b/Documentation/devicetree/bindings/mailbox/mailbox.txt index be05b9746c69..af8ecee2ac68 100644 --- a/Documentation/devicetree/bindings/mailbox/mailbox.txt +++ b/Documentation/devicetree/bindings/mailbox/mailbox.txt @@ -23,6 +23,11 @@ Required property: Optional property: - mbox-names: List of identifier strings for each mailbox channel. +- shmem : List of phandle pointing to the shared memory(SHM) area between the + users of these mailboxes for IPC, one for each mailbox. This shared + memory can be part of any memory reserved for the purpose of this + communication between the mailbox client and the remote. + Example: pwr_cntrl: power { @@ -30,3 +35,26 @@ Example: mbox-names = "pwr-ctrl", "rpc"; mboxes = <&mailbox 0 &mailbox 1>; }; + +Example with shared memory(shmem): + + sram: sram@50000000 { + compatible = "mmio-sram"; + reg = <0x50000000 0x10000>; + + #address-cells = <1>; + #size-cells = <1>; + ranges = <0 0x50000000 0x10000>; + + cl_shmem: shmem@0 { + compatible = "client-shmem"; + reg = <0x0 0x200>; + }; + }; + + client@2e000000 { + ... + mboxes = <&mailbox 0>; + shmem = <&cl_shmem>; + .. + }; diff --git a/Documentation/devicetree/bindings/memory-controllers/ti/emif.txt b/Documentation/devicetree/bindings/memory-controllers/ti/emif.txt index 621b41c79faa..44d71469c914 100644 --- a/Documentation/devicetree/bindings/memory-controllers/ti/emif.txt +++ b/Documentation/devicetree/bindings/memory-controllers/ti/emif.txt @@ -3,7 +3,9 @@ EMIF - External Memory Interface - is an SDRAM controller used in TI SoCs. EMIF supports, based on the IP revision, one or more of DDR2/DDR3/LPDDR2 protocols. This binding describes a given instance -of the EMIF IP and memory parts attached to it. +of the EMIF IP and memory parts attached to it. Certain revisions +of the EMIF controller also contain optional ECC support, which +corrects one bit errors and detects two bit errors. Required properties: - compatible : Should be of the form "ti,emif-<ip-rev>" where <ip-rev> @@ -11,6 +13,8 @@ Required properties: compatible should be one of the following: "ti,emif-am3352" "ti,emif-am4372" + "ti,emif-dra7xx" + "ti,emif-keystone" - phy-type : <u32> indicating the DDR phy type. Following are the allowed values @@ -22,6 +26,7 @@ Required properties: - ti,hwmods : For TI hwmods processing and omap device creation the value shall be "emif<n>" where <n> is the number of the EMIF instance with base 1. +- interrupts : interrupt used by the controller Required only for "ti,emif-am3352" and "ti,emif-am4372": - sram : Phandles for generic sram driver nodes, @@ -71,3 +76,9 @@ emif: emif@4c000000 { sram = <&pm_sram_code &pm_sram_data>; }; + +emif1: emif@4c000000 { + compatible = "ti,emif-dra7xx"; + reg = <0x4c000000 0x200>; + interrupts = <GIC_SPI 105 IRQ_TYPE_LEVEL_HIGH>; +}; diff --git a/Documentation/devicetree/bindings/mfd/aspeed-lpc.txt b/Documentation/devicetree/bindings/mfd/aspeed-lpc.txt index 69aadee00d5f..34dd89087cff 100644 --- a/Documentation/devicetree/bindings/mfd/aspeed-lpc.txt +++ b/Documentation/devicetree/bindings/mfd/aspeed-lpc.txt @@ -176,3 +176,24 @@ lhc: lhc@20 { compatible = "aspeed,ast2500-lhc"; reg = <0x20 0x24 0x48 0x8>; }; + +LPC reset control +----------------- + +The UARTs present in the ASPEED SoC can have their resets tied to the reset +state of the LPC bus. Some systems may chose to modify this configuration. + +Required properties: + + - compatible: "aspeed,ast2500-lpc-reset" or + "aspeed,ast2400-lpc-reset" + - reg: offset and length of the IP in the LHC memory region + - #reset-controller indicates the number of reset cells expected + +Example: + +lpc_reset: reset-controller@18 { + compatible = "aspeed,ast2500-lpc-reset"; + reg = <0x18 0x4>; + #reset-cells = <1>; +}; diff --git a/Documentation/devicetree/bindings/mips/mscc.txt b/Documentation/devicetree/bindings/mips/mscc.txt new file mode 100644 index 000000000000..ae15ec333542 --- /dev/null +++ b/Documentation/devicetree/bindings/mips/mscc.txt @@ -0,0 +1,43 @@ +* Microsemi MIPS CPUs + +Boards with a SoC of the Microsemi MIPS family shall have the following +properties: + +Required properties: +- compatible: "mscc,ocelot" + + +* Other peripherals: + +o CPU chip regs: + +The SoC has a few registers (DEVCPU_GCB:CHIP_REGS) handling miscellaneous +functionalities: chip ID, general purpose register for software use, reset +controller, hardware status and configuration, efuses. + +Required properties: +- compatible: Should be "mscc,ocelot-chip-regs", "simple-mfd", "syscon" +- reg : Should contain registers location and length + +Example: + syscon@71070000 { + compatible = "mscc,ocelot-chip-regs", "simple-mfd", "syscon"; + reg = <0x71070000 0x1c>; + }; + + +o CPU system control: + +The SoC has a few registers (ICPU_CFG:CPU_SYSTEM_CTRL) handling configuration of +the CPU: 8 general purpose registers, reset control, CPU en/disabling, CPU +endianness, CPU bus control, CPU status. + +Required properties: +- compatible: Should be "mscc,ocelot-cpu-syscon", "syscon" +- reg : Should contain registers location and length + +Example: + syscon@70000000 { + compatible = "mscc,ocelot-cpu-syscon", "syscon"; + reg = <0x70000000 0x2c>; + }; diff --git a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt index 50bf611a4d2c..13e70409e8ac 100644 --- a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt +++ b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt @@ -12,6 +12,7 @@ Required properties: - "amlogic,meson-gxbb-mmc" - "amlogic,meson-gxl-mmc" - "amlogic,meson-gxm-mmc" + - "amlogic,meson-axg-mmc" - clocks : A list of phandle + clock-specifier pairs for the clocks listed in clock-names. - clock-names: Should contain the following: "core" - Main peripheral bus clock @@ -19,6 +20,7 @@ Required properties: "clkin1" - Other parent clock of internal mux The driver has an internal mux clock which switches between clkin0 and clkin1 depending on the clock rate requested by the MMC core. +- resets : phandle of the internal reset line Example: @@ -29,4 +31,5 @@ Example: clocks = <&clkc CLKID_SD_EMMC_A>, <&xtal>, <&clkc CLKID_FCLK_DIV2>; clock-names = "core", "clkin0", "clkin1"; pinctrl-0 = <&emmc_pins>; + resets = <&reset RESET_SD_EMMC_A>; }; diff --git a/Documentation/devicetree/bindings/mmc/bluefield-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/bluefield-dw-mshc.txt new file mode 100644 index 000000000000..b0f0999ea1a9 --- /dev/null +++ b/Documentation/devicetree/bindings/mmc/bluefield-dw-mshc.txt @@ -0,0 +1,29 @@ +* Mellanox Bluefield SoC specific extensions to the Synopsys Designware + Mobile Storage Host Controller + +Read synopsys-dw-mshc.txt for more details + +The Synopsys designware mobile storage host controller is used to interface +a SoC with storage medium such as eMMC or SD/MMC cards. This file documents +differences between the core Synopsys dw mshc controller properties described +by synopsys-dw-mshc.txt and the properties used by the Mellanox Bluefield SoC +specific extensions to the Synopsys Designware Mobile Storage Host Controller. + +Required Properties: + +* compatible: should be one of the following. + - "mellanox,bluefield-dw-mshc": for controllers with Mellanox Bluefield SoC + specific extensions. + +Example: + + /* Mellanox Bluefield SoC MMC */ + mmc@6008000 { + compatible = "mellanox,bluefield-dw-mshc"; + reg = <0x6008000 0x400>; + interrupts = <32>; + fifo-depth = <0x100>; + clock-frequency = <24000000>; + bus-width = <8>; + cap-mmc-highspeed; + }; diff --git a/Documentation/devicetree/bindings/mmc/jz4740.txt b/Documentation/devicetree/bindings/mmc/jz4740.txt new file mode 100644 index 000000000000..7cd8c432d7c8 --- /dev/null +++ b/Documentation/devicetree/bindings/mmc/jz4740.txt @@ -0,0 +1,38 @@ +* Ingenic JZ47xx MMC controllers + +This file documents the device tree properties used for the MMC controller in +Ingenic JZ4740/JZ4780 SoCs. These are in addition to the core MMC properties +described in mmc.txt. + +Required properties: +- compatible: Should be one of the following: + - "ingenic,jz4740-mmc" for the JZ4740 + - "ingenic,jz4780-mmc" for the JZ4780 +- reg: Should contain the MMC controller registers location and length. +- interrupts: Should contain the interrupt specifier of the MMC controller. +- clocks: Clock for the MMC controller. + +Optional properties: +- dmas: List of DMA specifiers with the controller specific format + as described in the generic DMA client binding. A tx and rx + specifier is required. +- dma-names: RX and TX DMA request names. + Should be "rx" and "tx", in that order. + +For additional details on DMA client bindings see ../dma/dma.txt. + +Example: + +mmc0: mmc@13450000 { + compatible = "ingenic,jz4780-mmc"; + reg = <0x13450000 0x1000>; + + interrupt-parent = <&intc>; + interrupts = <37>; + + clocks = <&cgu JZ4780_CLK_MSC0>; + clock-names = "mmc"; + + dmas = <&dma JZ4780_DMA_MSC0_RX 0xffffffff>, <&dma JZ4780_DMA_MSC0_TX 0xffffffff>; + dma-names = "rx", "tx"; +}; diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt b/Documentation/devicetree/bindings/mmc/mmc.txt index 467cd7b147ce..f5a0923b34ca 100644 --- a/Documentation/devicetree/bindings/mmc/mmc.txt +++ b/Documentation/devicetree/bindings/mmc/mmc.txt @@ -19,6 +19,8 @@ Optional properties: - wp-gpios: Specify GPIOs for write protection, see gpio binding - cd-inverted: when present, polarity on the CD line is inverted. See the note below for the case, when a GPIO is used for the CD line +- cd-debounce-delay-ms: Set delay time before detecting card after card insert interrupt. + It's only valid when cd-gpios is present. - wp-inverted: when present, polarity on the WP line is inverted. See the note below for the case, when a GPIO is used for the WP line - disable-wp: When set no physical WP line is present. This property should @@ -56,6 +58,10 @@ Optional properties: - fixed-emmc-driver-type: for non-removable eMMC, enforce this driver type. The value <n> is the driver type as specified in the eMMC specification (table 206 in spec version 5.1). +- post-power-on-delay-ms : It was invented for MMC pwrseq-simple which could + be referred to mmc-pwrseq-simple.txt. But now it's reused as a tunable delay + waiting for I/O signalling and card power supply to be stable, regardless of + whether pwrseq-simple is used. Default to 10ms if no available. *NOTE* on CD and WP polarity. To use common for all SD/MMC host controllers line polarity properties, we have to fix the meaning of the "normal" and "inverted" diff --git a/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt b/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt index c6558785e61b..8ce49b255974 100644 --- a/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt +++ b/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt @@ -21,7 +21,7 @@ Required Properties: - "rockchip,rk3399-dw-mshc", "rockchip,rk3288-dw-mshc": for Rockchip RK3399 Optional Properties: -* clocks: from common clock binding: if ciu_drive and ciu_sample are +* clocks: from common clock binding: if ciu-drive and ciu-sample are specified in clock-names, should contain handles to these clocks. * clock-names: Apart from the clock-names described in synopsys-dw-mshc.txt @@ -29,7 +29,7 @@ Optional Properties: to control the clock phases, "ciu-sample" is required for tuning high- speed modes. -* rockchip,default-sample-phase: The default phase to set ciu_sample at +* rockchip,default-sample-phase: The default phase to set ciu-sample at probing, low speeds or in case where all phases work at tuning time. If not specified 0 deg will be used. diff --git a/Documentation/devicetree/bindings/mmc/sdhci-omap.txt b/Documentation/devicetree/bindings/mmc/sdhci-omap.txt index 51775a372c06..393848c2138e 100644 --- a/Documentation/devicetree/bindings/mmc/sdhci-omap.txt +++ b/Documentation/devicetree/bindings/mmc/sdhci-omap.txt @@ -4,7 +4,14 @@ Refer to mmc.txt for standard MMC bindings. Required properties: - compatible: Should be "ti,dra7-sdhci" for DRA7 and DRA72 controllers + Should be "ti,k2g-sdhci" for K2G - ti,hwmods: Must be "mmc<n>", <n> is controller instance starting 1 + (Not required for K2G). +- pinctrl-names: Should be subset of "default", "hs", "sdr12", "sdr25", "sdr50", + "ddr50-rev11", "sdr104-rev11", "ddr50", "sdr104", + "ddr_1_8v-rev11", "ddr_1_8v" or "ddr_3_3v", "hs200_1_8v-rev11", + "hs200_1_8v", +- pinctrl-<n> : Pinctrl states as described in bindings/pinctrl/pinctrl-bindings.txt Example: mmc1: mmc@4809c000 { diff --git a/Documentation/devicetree/bindings/mmc/tmio_mmc.txt b/Documentation/devicetree/bindings/mmc/tmio_mmc.txt index 2d5287eeed95..ee978c95189d 100644 --- a/Documentation/devicetree/bindings/mmc/tmio_mmc.txt +++ b/Documentation/devicetree/bindings/mmc/tmio_mmc.txt @@ -26,6 +26,8 @@ Required properties: "renesas,sdhi-r8a7794" - SDHI IP on R8A7794 SoC "renesas,sdhi-r8a7795" - SDHI IP on R8A7795 SoC "renesas,sdhi-r8a7796" - SDHI IP on R8A7796 SoC + "renesas,sdhi-r8a77965" - SDHI IP on R8A77965 SoC + "renesas,sdhi-r8a77980" - SDHI IP on R8A77980 SoC "renesas,sdhi-r8a77995" - SDHI IP on R8A77995 SoC "renesas,sdhi-shmobile" - a generic sh-mobile SDHI controller "renesas,rcar-gen1-sdhi" - a generic R-Car Gen1 SDHI controller diff --git a/Documentation/devicetree/bindings/mtd/fsl-quadspi.txt b/Documentation/devicetree/bindings/mtd/fsl-quadspi.txt index 63d4d626fbd5..483e9cfac1b1 100644 --- a/Documentation/devicetree/bindings/mtd/fsl-quadspi.txt +++ b/Documentation/devicetree/bindings/mtd/fsl-quadspi.txt @@ -39,3 +39,27 @@ qspi0: quadspi@40044000 { .... }; }; + +Example showing the usage of two SPI NOR devices: + +&qspi2 { + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_qspi2>; + status = "okay"; + + flash0: n25q256a@0 { + #address-cells = <1>; + #size-cells = <1>; + compatible = "micron,n25q256a", "jedec,spi-nor"; + spi-max-frequency = <29000000>; + reg = <0>; + }; + + flash1: n25q256a@1 { + #address-cells = <1>; + #size-cells = <1>; + compatible = "micron,n25q256a", "jedec,spi-nor"; + spi-max-frequency = <29000000>; + reg = <1>; + }; +}; diff --git a/Documentation/devicetree/bindings/mtd/marvell-nand.txt b/Documentation/devicetree/bindings/mtd/marvell-nand.txt index c08fb477b3c6..e0c790706b9b 100644 --- a/Documentation/devicetree/bindings/mtd/marvell-nand.txt +++ b/Documentation/devicetree/bindings/mtd/marvell-nand.txt @@ -14,7 +14,10 @@ Required properties: - #address-cells: shall be set to 1. Encode the NAND CS. - #size-cells: shall be set to 0. - interrupts: shall define the NAND controller interrupt. -- clocks: shall reference the NAND controller clock. +- clocks: shall reference the NAND controller clocks, the second one is + is only needed for the Armada 7K/8K SoCs +- clock-names: mandatory if there is a second clock, in this case there + should be one clock named "core" and another one named "reg" - marvell,system-controller: Set to retrieve the syscon node that handles NAND controller related registers (only required with the "marvell,armada-8k-nand[-controller]" compatibles). diff --git a/Documentation/devicetree/bindings/mtd/mtd-physmap.txt b/Documentation/devicetree/bindings/mtd/mtd-physmap.txt index 4a0a48bf4ecb..232fa12e90ef 100644 --- a/Documentation/devicetree/bindings/mtd/mtd-physmap.txt +++ b/Documentation/devicetree/bindings/mtd/mtd-physmap.txt @@ -41,6 +41,13 @@ additional (optional) property is defined: - erase-size : The chip's physical erase block size in bytes. + The device tree may optionally contain endianness property. + little-endian or big-endian : It Represents the endianness that should be used + by the controller to properly read/write data + from/to the flash. If this property is missing, + the endianness is chosen by the system + (potentially based on extra configuration options). + The device tree may optionally contain sub-nodes describing partitions of the address space. See partition.txt for more detail. diff --git a/Documentation/devicetree/bindings/mtd/pxa3xx-nand.txt b/Documentation/devicetree/bindings/mtd/pxa3xx-nand.txt deleted file mode 100644 index d4ee4da58463..000000000000 --- a/Documentation/devicetree/bindings/mtd/pxa3xx-nand.txt +++ /dev/null @@ -1,50 +0,0 @@ -PXA3xx NAND DT bindings - -Required properties: - - - compatible: Should be set to one of the following: - marvell,pxa3xx-nand - marvell,armada370-nand - marvell,armada-8k-nand - - reg: The register base for the controller - - interrupts: The interrupt to map - - #address-cells: Set to <1> if the node includes partitions - - marvell,system-controller: Set to retrieve the syscon node that handles - NAND controller related registers (only required - with marvell,armada-8k-nand compatible). - -Optional properties: - - - dmas: dma data channel, see dma.txt binding doc - - marvell,nand-enable-arbiter: Set to enable the bus arbiter - - marvell,nand-keep-config: Set to keep the NAND controller config as set - by the bootloader - - num-cs: Number of chipselect lines to use - - nand-on-flash-bbt: boolean to enable on flash bbt option if - not present false - - nand-ecc-strength: number of bits to correct per ECC step - - nand-ecc-step-size: number of data bytes covered by a single ECC step - -The following ECC strength and step size are currently supported: - - - nand-ecc-strength = <1>, nand-ecc-step-size = <512> - - nand-ecc-strength = <4>, nand-ecc-step-size = <512> - - nand-ecc-strength = <8>, nand-ecc-step-size = <512> - -Example: - - nand0: nand@43100000 { - compatible = "marvell,pxa3xx-nand"; - reg = <0x43100000 90>; - interrupts = <45>; - dmas = <&pdma 97 0>; - dma-names = "data"; - #address-cells = <1>; - - marvell,nand-enable-arbiter; - marvell,nand-keep-config; - num-cs = <1>; - - /* partitions (optional) */ - }; - diff --git a/Documentation/devicetree/bindings/mtd/sunxi-nand.txt b/Documentation/devicetree/bindings/mtd/sunxi-nand.txt index 5e13a5cdff03..0734f03bf3d3 100644 --- a/Documentation/devicetree/bindings/mtd/sunxi-nand.txt +++ b/Documentation/devicetree/bindings/mtd/sunxi-nand.txt @@ -24,8 +24,8 @@ Optional properties: - allwinner,rb : shall contain the native Ready/Busy ids. or - rb-gpios : shall contain the gpios used as R/B pins. -- nand-ecc-mode : one of the supported ECC modes ("hw", "hw_syndrome", "soft", - "soft_bch" or "none") +- nand-ecc-mode : one of the supported ECC modes ("hw", "soft", "soft_bch" or + "none") see Documentation/devicetree/bindings/mtd/nand.txt for generic bindings. diff --git a/Documentation/devicetree/bindings/net/can/rcar_canfd.txt b/Documentation/devicetree/bindings/net/can/rcar_canfd.txt index 93c3a6ae32f9..ac71daa46195 100644 --- a/Documentation/devicetree/bindings/net/can/rcar_canfd.txt +++ b/Documentation/devicetree/bindings/net/can/rcar_canfd.txt @@ -5,7 +5,9 @@ Required properties: - compatible: Must contain one or more of the following: - "renesas,rcar-gen3-canfd" for R-Car Gen3 compatible controller. - "renesas,r8a7795-canfd" for R8A7795 (R-Car H3) compatible controller. - - "renesas,r8a7796-canfd" for R8A7796 (R-Car M3) compatible controller. + - "renesas,r8a7796-canfd" for R8A7796 (R-Car M3-W) compatible controller. + - "renesas,r8a77970-canfd" for R8A77970 (R-Car V3M) compatible controller. + - "renesas,r8a77980-canfd" for R8A77980 (R-Car V3H) compatible controller. When compatible with the generic version, nodes must list the SoC-specific version corresponding to the platform first, followed by the diff --git a/Documentation/devicetree/bindings/net/dsa/b53.txt b/Documentation/devicetree/bindings/net/dsa/b53.txt index 8acf51a4dfa8..47a6a7fe0b86 100644 --- a/Documentation/devicetree/bindings/net/dsa/b53.txt +++ b/Documentation/devicetree/bindings/net/dsa/b53.txt @@ -10,6 +10,7 @@ Required properties: "brcm,bcm53128" "brcm,bcm5365" "brcm,bcm5395" + "brcm,bcm5389" "brcm,bcm5397" "brcm,bcm5398" diff --git a/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt b/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt index 594982c6b9f9..79bf352e659c 100644 --- a/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt +++ b/Documentation/devicetree/bindings/net/fsl-tsec-phy.txt @@ -6,7 +6,11 @@ the definition of the PHY node in booting-without-of.txt for an example of how to define a PHY. Required properties: - - reg : Offset and length of the register set for the device + - reg : Offset and length of the register set for the device, and optionally + the offset and length of the TBIPA register (TBI PHY address + register). If TBIPA register is not specified, the driver will + attempt to infer it from the register set specified (your mileage may + vary). - compatible : Should define the compatible device type for the mdio. Currently supported strings/devices are: - "fsl,gianfar-tbi" diff --git a/Documentation/devicetree/bindings/net/marvell-pp2.txt b/Documentation/devicetree/bindings/net/marvell-pp2.txt index 1814fa13f6ab..fc019df0d863 100644 --- a/Documentation/devicetree/bindings/net/marvell-pp2.txt +++ b/Documentation/devicetree/bindings/net/marvell-pp2.txt @@ -21,9 +21,10 @@ Required properties: - main controller clock (for both armada-375-pp2 and armada-7k-pp2) - GOP clock (for both armada-375-pp2 and armada-7k-pp2) - MG clock (only for armada-7k-pp2) + - MG Core clock (only for armada-7k-pp2) - AXI clock (only for armada-7k-pp2) -- clock-names: names of used clocks, must be "pp_clk", "gop_clk", "mg_clk" - and "axi_clk" (the 2 latter only for armada-7k-pp2). +- clock-names: names of used clocks, must be "pp_clk", "gop_clk", "mg_clk", + "mg_core_clk" and "axi_clk" (the 3 latter only for armada-7k-pp2). The ethernet ports are represented by subnodes. At least one port is required. @@ -80,8 +81,8 @@ cpm_ethernet: ethernet@0 { compatible = "marvell,armada-7k-pp22"; reg = <0x0 0x100000>, <0x129000 0xb000>; clocks = <&cpm_syscon0 1 3>, <&cpm_syscon0 1 9>, - <&cpm_syscon0 1 5>, <&cpm_syscon0 1 18>; - clock-names = "pp_clk", "gop_clk", "gp_clk", "axi_clk"; + <&cpm_syscon0 1 5>, <&cpm_syscon0 1 6>, <&cpm_syscon0 1 18>; + clock-names = "pp_clk", "gop_clk", "mg_clk", "mg_core_clk", "axi_clk"; eth0: eth0 { interrupts = <ICU_GRP_NSR 39 IRQ_TYPE_LEVEL_HIGH>, diff --git a/Documentation/devicetree/bindings/net/micrel-ksz90x1.txt b/Documentation/devicetree/bindings/net/micrel-ksz90x1.txt index 42a248301615..e22d8cfea687 100644 --- a/Documentation/devicetree/bindings/net/micrel-ksz90x1.txt +++ b/Documentation/devicetree/bindings/net/micrel-ksz90x1.txt @@ -57,6 +57,13 @@ KSZ9031: - txd2-skew-ps : Skew control of TX data 2 pad - txd3-skew-ps : Skew control of TX data 3 pad + - micrel,force-master: + Boolean, force phy to master mode. Only set this option if the phy + reference clock provided at CLK125_NDO pin is used as MAC reference + clock because the clock jitter in slave mode is to high (errata#2). + Attention: The link partner must be configurable as slave otherwise + no link will be established. + Examples: mdio { diff --git a/Documentation/devicetree/bindings/net/renesas,ravb.txt b/Documentation/devicetree/bindings/net/renesas,ravb.txt index c306f55d335b..890526dbfc26 100644 --- a/Documentation/devicetree/bindings/net/renesas,ravb.txt +++ b/Documentation/devicetree/bindings/net/renesas,ravb.txt @@ -18,6 +18,7 @@ Required properties: - "renesas,etheravb-r8a7795" for the R8A7795 SoC. - "renesas,etheravb-r8a7796" for the R8A7796 SoC. + - "renesas,etheravb-r8a77965" for the R8A77965 SoC. - "renesas,etheravb-r8a77970" for the R8A77970 SoC. - "renesas,etheravb-r8a77980" for the R8A77980 SoC. - "renesas,etheravb-r8a77995" for the R8A77995 SoC. diff --git a/Documentation/devicetree/bindings/nvmem/zii,rave-sp-eeprom.txt b/Documentation/devicetree/bindings/nvmem/zii,rave-sp-eeprom.txt new file mode 100644 index 000000000000..d5e22fc67d66 --- /dev/null +++ b/Documentation/devicetree/bindings/nvmem/zii,rave-sp-eeprom.txt @@ -0,0 +1,40 @@ +Zodiac Inflight Innovations RAVE EEPROM Bindings + +RAVE SP EEPROM device is a "MFD cell" device exposing physical EEPROM +attached to RAVE Supervisory Processor. It is expected that its Device +Tree node is specified as a child of the node corresponding to the +parent RAVE SP device (as documented in +Documentation/devicetree/bindings/mfd/zii,rave-sp.txt) + +Required properties: + +- compatible: Should be "zii,rave-sp-eeprom" + +Optional properties: + +- zii,eeprom-name: Unique EEPROM identifier describing its function in the + system. Will be used as created NVMEM deivce's name. + +Data cells: + +Data cells are child nodes of eerpom node, bindings for which are +documented in Documentation/bindings/nvmem/nvmem.txt + +Example: + + rave-sp { + compatible = "zii,rave-sp-rdu1"; + current-speed = <38400>; + + eeprom@a4 { + compatible = "zii,rave-sp-eeprom"; + reg = <0xa4 0x4000>; + #address-cells = <1>; + #size-cells = <1>; + zii,eeprom-name = "main-eeprom"; + + wdt_timeout: wdt-timeout@81 { + reg = <0x81 2>; + }; + }; + } diff --git a/Documentation/devicetree/bindings/opp/kryo-cpufreq.txt b/Documentation/devicetree/bindings/opp/kryo-cpufreq.txt new file mode 100644 index 000000000000..c2127b96805a --- /dev/null +++ b/Documentation/devicetree/bindings/opp/kryo-cpufreq.txt @@ -0,0 +1,680 @@ +Qualcomm Technologies, Inc. KRYO CPUFreq and OPP bindings +=================================== + +In Certain Qualcomm Technologies, Inc. SoCs like apq8096 and msm8996 +that have KRYO processors, the CPU ferequencies subset and voltage value +of each OPP varies based on the silicon variant in use. +Qualcomm Technologies, Inc. Process Voltage Scaling Tables +defines the voltage and frequency value based on the msm-id in SMEM +and speedbin blown in the efuse combination. +The qcom-cpufreq-kryo driver reads the msm-id and efuse value from the SoC +to provide the OPP framework with required information (existing HW bitmap). +This is used to determine the voltage and frequency value for each OPP of +operating-points-v2 table when it is parsed by the OPP framework. + +Required properties: +-------------------- +In 'cpus' nodes: +- operating-points-v2: Phandle to the operating-points-v2 table to use. + +In 'operating-points-v2' table: +- compatible: Should be + - 'operating-points-v2-kryo-cpu' for apq8096 and msm8996. +- nvmem-cells: A phandle pointing to a nvmem-cells node representing the + efuse registers that has information about the + speedbin that is used to select the right frequency/voltage + value pair. + Please refer the for nvmem-cells + bindings Documentation/devicetree/bindings/nvmem/nvmem.txt + and also examples below. + +In every OPP node: +- opp-supported-hw: A single 32 bit bitmap value, representing compatible HW. + Bitmap: + 0: MSM8996 V3, speedbin 0 + 1: MSM8996 V3, speedbin 1 + 2: MSM8996 V3, speedbin 2 + 3: unused + 4: MSM8996 SG, speedbin 0 + 5: MSM8996 SG, speedbin 1 + 6: MSM8996 SG, speedbin 2 + 7-31: unused + +Example 1: +--------- + + cpus { + #address-cells = <2>; + #size-cells = <0>; + + CPU0: cpu@0 { + device_type = "cpu"; + compatible = "qcom,kryo"; + reg = <0x0 0x0>; + enable-method = "psci"; + clocks = <&kryocc 0>; + cpu-supply = <&pm8994_s11_saw>; + operating-points-v2 = <&cluster0_opp>; + #cooling-cells = <2>; + next-level-cache = <&L2_0>; + L2_0: l2-cache { + compatible = "cache"; + cache-level = <2>; + }; + }; + + CPU1: cpu@1 { + device_type = "cpu"; + compatible = "qcom,kryo"; + reg = <0x0 0x1>; + enable-method = "psci"; + clocks = <&kryocc 0>; + cpu-supply = <&pm8994_s11_saw>; + operating-points-v2 = <&cluster0_opp>; + #cooling-cells = <2>; + next-level-cache = <&L2_0>; + }; + + CPU2: cpu@100 { + device_type = "cpu"; + compatible = "qcom,kryo"; + reg = <0x0 0x100>; + enable-method = "psci"; + clocks = <&kryocc 1>; + cpu-supply = <&pm8994_s11_saw>; + operating-points-v2 = <&cluster1_opp>; + #cooling-cells = <2>; + next-level-cache = <&L2_1>; + L2_1: l2-cache { + compatible = "cache"; + cache-level = <2>; + }; + }; + + CPU3: cpu@101 { + device_type = "cpu"; + compatible = "qcom,kryo"; + reg = <0x0 0x101>; + enable-method = "psci"; + clocks = <&kryocc 1>; + cpu-supply = <&pm8994_s11_saw>; + operating-points-v2 = <&cluster1_opp>; + #cooling-cells = <2>; + next-level-cache = <&L2_1>; + }; + + cpu-map { + cluster0 { + core0 { + cpu = <&CPU0>; + }; + + core1 { + cpu = <&CPU1>; + }; + }; + + cluster1 { + core0 { + cpu = <&CPU2>; + }; + + core1 { + cpu = <&CPU3>; + }; + }; + }; + }; + + cluster0_opp: opp_table0 { + compatible = "operating-points-v2-kryo-cpu"; + nvmem-cells = <&speedbin_efuse>; + opp-shared; + + opp-307200000 { + opp-hz = /bits/ 64 <307200000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x77>; + clock-latency-ns = <200000>; + }; + opp-384000000 { + opp-hz = /bits/ 64 <384000000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-422400000 { + opp-hz = /bits/ 64 <422400000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-460800000 { + opp-hz = /bits/ 64 <460800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-480000000 { + opp-hz = /bits/ 64 <480000000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-537600000 { + opp-hz = /bits/ 64 <537600000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-556800000 { + opp-hz = /bits/ 64 <556800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-614400000 { + opp-hz = /bits/ 64 <614400000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-652800000 { + opp-hz = /bits/ 64 <652800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-691200000 { + opp-hz = /bits/ 64 <691200000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-729600000 { + opp-hz = /bits/ 64 <729600000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-768000000 { + opp-hz = /bits/ 64 <768000000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-844800000 { + opp-hz = /bits/ 64 <844800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x77>; + clock-latency-ns = <200000>; + }; + opp-902400000 { + opp-hz = /bits/ 64 <902400000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-960000000 { + opp-hz = /bits/ 64 <960000000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-979200000 { + opp-hz = /bits/ 64 <979200000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1036800000 { + opp-hz = /bits/ 64 <1036800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1056000000 { + opp-hz = /bits/ 64 <1056000000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1113600000 { + opp-hz = /bits/ 64 <1113600000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1132800000 { + opp-hz = /bits/ 64 <1132800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1190400000 { + opp-hz = /bits/ 64 <1190400000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1209600000 { + opp-hz = /bits/ 64 <1209600000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1228800000 { + opp-hz = /bits/ 64 <1228800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1286400000 { + opp-hz = /bits/ 64 <1286400000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1324800000 { + opp-hz = /bits/ 64 <1324800000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x5>; + clock-latency-ns = <200000>; + }; + opp-1363200000 { + opp-hz = /bits/ 64 <1363200000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x72>; + clock-latency-ns = <200000>; + }; + opp-1401600000 { + opp-hz = /bits/ 64 <1401600000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x5>; + clock-latency-ns = <200000>; + }; + opp-1440000000 { + opp-hz = /bits/ 64 <1440000000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1478400000 { + opp-hz = /bits/ 64 <1478400000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x1>; + clock-latency-ns = <200000>; + }; + opp-1497600000 { + opp-hz = /bits/ 64 <1497600000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x4>; + clock-latency-ns = <200000>; + }; + opp-1516800000 { + opp-hz = /bits/ 64 <1516800000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1593600000 { + opp-hz = /bits/ 64 <1593600000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x71>; + clock-latency-ns = <200000>; + }; + opp-1996800000 { + opp-hz = /bits/ 64 <1996800000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x20>; + clock-latency-ns = <200000>; + }; + opp-2188800000 { + opp-hz = /bits/ 64 <2188800000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x10>; + clock-latency-ns = <200000>; + }; + }; + + cluster1_opp: opp_table1 { + compatible = "operating-points-v2-kryo-cpu"; + nvmem-cells = <&speedbin_efuse>; + opp-shared; + + opp-307200000 { + opp-hz = /bits/ 64 <307200000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x77>; + clock-latency-ns = <200000>; + }; + opp-384000000 { + opp-hz = /bits/ 64 <384000000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-403200000 { + opp-hz = /bits/ 64 <403200000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-460800000 { + opp-hz = /bits/ 64 <460800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-480000000 { + opp-hz = /bits/ 64 <480000000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-537600000 { + opp-hz = /bits/ 64 <537600000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-556800000 { + opp-hz = /bits/ 64 <556800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-614400000 { + opp-hz = /bits/ 64 <614400000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-652800000 { + opp-hz = /bits/ 64 <652800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-691200000 { + opp-hz = /bits/ 64 <691200000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-729600000 { + opp-hz = /bits/ 64 <729600000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-748800000 { + opp-hz = /bits/ 64 <748800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-806400000 { + opp-hz = /bits/ 64 <806400000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-825600000 { + opp-hz = /bits/ 64 <825600000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-883200000 { + opp-hz = /bits/ 64 <883200000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-902400000 { + opp-hz = /bits/ 64 <902400000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-940800000 { + opp-hz = /bits/ 64 <940800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-979200000 { + opp-hz = /bits/ 64 <979200000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1036800000 { + opp-hz = /bits/ 64 <1036800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1056000000 { + opp-hz = /bits/ 64 <1056000000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1113600000 { + opp-hz = /bits/ 64 <1113600000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1132800000 { + opp-hz = /bits/ 64 <1132800000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1190400000 { + opp-hz = /bits/ 64 <1190400000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1209600000 { + opp-hz = /bits/ 64 <1209600000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1248000000 { + opp-hz = /bits/ 64 <1248000000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1286400000 { + opp-hz = /bits/ 64 <1286400000>; + opp-microvolt = <905000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1324800000 { + opp-hz = /bits/ 64 <1324800000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1363200000 { + opp-hz = /bits/ 64 <1363200000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1401600000 { + opp-hz = /bits/ 64 <1401600000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1440000000 { + opp-hz = /bits/ 64 <1440000000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1478400000 { + opp-hz = /bits/ 64 <1478400000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1516800000 { + opp-hz = /bits/ 64 <1516800000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1555200000 { + opp-hz = /bits/ 64 <1555200000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1593600000 { + opp-hz = /bits/ 64 <1593600000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1632000000 { + opp-hz = /bits/ 64 <1632000000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1670400000 { + opp-hz = /bits/ 64 <1670400000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1708800000 { + opp-hz = /bits/ 64 <1708800000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1747200000 { + opp-hz = /bits/ 64 <1747200000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x70>; + clock-latency-ns = <200000>; + }; + opp-1785600000 { + opp-hz = /bits/ 64 <1785600000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x7>; + clock-latency-ns = <200000>; + }; + opp-1804800000 { + opp-hz = /bits/ 64 <1804800000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x6>; + clock-latency-ns = <200000>; + }; + opp-1824000000 { + opp-hz = /bits/ 64 <1824000000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x71>; + clock-latency-ns = <200000>; + }; + opp-1900800000 { + opp-hz = /bits/ 64 <1900800000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x74>; + clock-latency-ns = <200000>; + }; + opp-1920000000 { + opp-hz = /bits/ 64 <1920000000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x1>; + clock-latency-ns = <200000>; + }; + opp-1977600000 { + opp-hz = /bits/ 64 <1977600000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x30>; + clock-latency-ns = <200000>; + }; + opp-1996800000 { + opp-hz = /bits/ 64 <1996800000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x1>; + clock-latency-ns = <200000>; + }; + opp-2054400000 { + opp-hz = /bits/ 64 <2054400000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x30>; + clock-latency-ns = <200000>; + }; + opp-2073600000 { + opp-hz = /bits/ 64 <2073600000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x1>; + clock-latency-ns = <200000>; + }; + opp-2150400000 { + opp-hz = /bits/ 64 <2150400000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x31>; + clock-latency-ns = <200000>; + }; + opp-2246400000 { + opp-hz = /bits/ 64 <2246400000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x10>; + clock-latency-ns = <200000>; + }; + opp-2342400000 { + opp-hz = /bits/ 64 <2342400000>; + opp-microvolt = <1140000 905000 1140000>; + opp-supported-hw = <0x10>; + clock-latency-ns = <200000>; + }; + }; + +.... + +reserved-memory { + #address-cells = <2>; + #size-cells = <2>; + ranges; +.... + smem_mem: smem-mem@86000000 { + reg = <0x0 0x86000000 0x0 0x200000>; + no-map; + }; +.... +}; + +smem { + compatible = "qcom,smem"; + memory-region = <&smem_mem>; + hwlocks = <&tcsr_mutex 3>; +}; + +soc { +.... + qfprom: qfprom@74000 { + compatible = "qcom,qfprom"; + reg = <0x00074000 0x8ff>; + #address-cells = <1>; + #size-cells = <1>; + .... + speedbin_efuse: speedbin@133 { + reg = <0x133 0x1>; + bits = <5 3>; + }; + }; +}; diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt index 4e4f30288c8b..c396c4c0af92 100644 --- a/Documentation/devicetree/bindings/opp/opp.txt +++ b/Documentation/devicetree/bindings/opp/opp.txt @@ -82,7 +82,10 @@ This defines voltage-current-frequency combinations along with other related properties. Required properties: -- opp-hz: Frequency in Hz, expressed as a 64-bit big-endian integer. +- opp-hz: Frequency in Hz, expressed as a 64-bit big-endian integer. This is a + required property for all device nodes but devices like power domains. The + power domain nodes must have another (implementation dependent) property which + uniquely identifies the OPP nodes. Optional properties: - opp-microvolt: voltage in micro Volts. @@ -159,7 +162,7 @@ Optional properties: - status: Marks the node enabled/disabled. -- required-opp: This contains phandle to an OPP node in another device's OPP +- required-opps: This contains phandle to an OPP node in another device's OPP table. It may contain an array of phandles, where each phandle points to an OPP of a different device. It should not contain multiple phandles to the OPP nodes in the same OPP table. This specifies the minimum required OPP of the diff --git a/Documentation/devicetree/bindings/pci/hisilicon-histb-pcie.txt b/Documentation/devicetree/bindings/pci/hisilicon-histb-pcie.txt index c84bc027930b..760b4d740616 100644 --- a/Documentation/devicetree/bindings/pci/hisilicon-histb-pcie.txt +++ b/Documentation/devicetree/bindings/pci/hisilicon-histb-pcie.txt @@ -34,6 +34,7 @@ Required properties Optional properties: - reset-gpios: The gpio to generate PCIe PERST# assert and deassert signal. +- vpcie-supply: The regulator in charge of PCIe port power. - phys: List of phandle and phy mode specifier, should be 0. - phy-names: Must be "phy". diff --git a/Documentation/devicetree/bindings/pci/mediatek-pcie.txt b/Documentation/devicetree/bindings/pci/mediatek-pcie.txt index 3a6ce55dd310..20227a875ac8 100644 --- a/Documentation/devicetree/bindings/pci/mediatek-pcie.txt +++ b/Documentation/devicetree/bindings/pci/mediatek-pcie.txt @@ -78,7 +78,7 @@ Examples for MT7623: #reset-cells = <1>; }; - pcie: pcie-controller@1a140000 { + pcie: pcie@1a140000 { compatible = "mediatek,mt7623-pcie"; device_type = "pci"; reg = <0 0x1a140000 0 0x1000>, /* PCIe shared registers */ @@ -111,7 +111,6 @@ Examples for MT7623: 0x83000000 0 0x60000000 0 0x60000000 0 0x10000000>; /* memory space */ pcie@0,0 { - device_type = "pci"; reg = <0x0000 0 0 0 0>; #address-cells = <3>; #size-cells = <2>; @@ -123,7 +122,6 @@ Examples for MT7623: }; pcie@1,0 { - device_type = "pci"; reg = <0x0800 0 0 0 0>; #address-cells = <3>; #size-cells = <2>; @@ -135,7 +133,6 @@ Examples for MT7623: }; pcie@2,0 { - device_type = "pci"; reg = <0x1000 0 0 0 0>; #address-cells = <3>; #size-cells = <2>; @@ -148,6 +145,7 @@ Examples for MT7623: }; Examples for MT2712: + pcie: pcie@11700000 { compatible = "mediatek,mt2712-pcie"; device_type = "pci"; @@ -169,7 +167,6 @@ Examples for MT2712: ranges = <0x82000000 0 0x20000000 0x0 0x20000000 0 0x10000000>; pcie0: pcie@0,0 { - device_type = "pci"; reg = <0x0000 0 0 0 0>; #address-cells = <3>; #size-cells = <2>; @@ -189,7 +186,6 @@ Examples for MT2712: }; pcie1: pcie@1,0 { - device_type = "pci"; reg = <0x0800 0 0 0 0>; #address-cells = <3>; #size-cells = <2>; @@ -210,6 +206,7 @@ Examples for MT2712: }; Examples for MT7622: + pcie: pcie@1a140000 { compatible = "mediatek,mt7622-pcie"; device_type = "pci"; @@ -243,7 +240,6 @@ Examples for MT7622: ranges = <0x82000000 0 0x20000000 0x0 0x20000000 0 0x10000000>; pcie0: pcie@0,0 { - device_type = "pci"; reg = <0x0000 0 0 0 0>; #address-cells = <3>; #size-cells = <2>; @@ -263,7 +259,6 @@ Examples for MT7622: }; pcie1: pcie@1,0 { - device_type = "pci"; reg = <0x0800 0 0 0 0>; #address-cells = <3>; #size-cells = <2>; diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie.txt b/Documentation/devicetree/bindings/pci/qcom,pcie.txt index 3c9d321b3d3b..1fd703bd73e0 100644 --- a/Documentation/devicetree/bindings/pci/qcom,pcie.txt +++ b/Documentation/devicetree/bindings/pci/qcom,pcie.txt @@ -189,6 +189,10 @@ Value type: <phandle> Definition: A phandle to the analog power supply for IC which generates reference clock +- vddpe-3v3-supply: + Usage: optional + Value type: <phandle> + Definition: A phandle to the PCIe endpoint power supply - phys: Usage: required for apq8084 diff --git a/Documentation/devicetree/bindings/pci/rcar-pci.txt b/Documentation/devicetree/bindings/pci/rcar-pci.txt index 76ba3a61d1a3..1fb614e615da 100644 --- a/Documentation/devicetree/bindings/pci/rcar-pci.txt +++ b/Documentation/devicetree/bindings/pci/rcar-pci.txt @@ -1,13 +1,15 @@ * Renesas R-Car PCIe interface Required properties: -compatible: "renesas,pcie-r8a7779" for the R8A7779 SoC; +compatible: "renesas,pcie-r8a7743" for the R8A7743 SoC; + "renesas,pcie-r8a7779" for the R8A7779 SoC; "renesas,pcie-r8a7790" for the R8A7790 SoC; "renesas,pcie-r8a7791" for the R8A7791 SoC; "renesas,pcie-r8a7793" for the R8A7793 SoC; "renesas,pcie-r8a7795" for the R8A7795 SoC; "renesas,pcie-r8a7796" for the R8A7796 SoC; - "renesas,pcie-rcar-gen2" for a generic R-Car Gen2 compatible device. + "renesas,pcie-rcar-gen2" for a generic R-Car Gen2 or + RZ/G1 compatible device. "renesas,pcie-rcar-gen3" for a generic R-Car Gen3 compatible device. When compatible with the generic version, nodes must list the diff --git a/Documentation/devicetree/bindings/arm/ccn.txt b/Documentation/devicetree/bindings/perf/arm-ccn.txt index 43b5a71a5a9d..43b5a71a5a9d 100644 --- a/Documentation/devicetree/bindings/arm/ccn.txt +++ b/Documentation/devicetree/bindings/perf/arm-ccn.txt diff --git a/Documentation/devicetree/bindings/phy/nvidia,tegra20-usb-phy.txt b/Documentation/devicetree/bindings/phy/nvidia,tegra20-usb-phy.txt index a9aa79fb90ed..1aa6f2674af5 100644 --- a/Documentation/devicetree/bindings/phy/nvidia,tegra20-usb-phy.txt +++ b/Documentation/devicetree/bindings/phy/nvidia,tegra20-usb-phy.txt @@ -21,7 +21,9 @@ Required properties : - timer: The timeout clock (clk_m). Present if phy_type == utmi. - utmi-pads: The clock needed to access the UTMI pad control registers. Present if phy_type == utmi. - - ulpi-link: The clock Tegra provides to the ULPI PHY (cdev2). + - ulpi-link: The clock Tegra provides to the ULPI PHY (usually pad DAP_MCLK2 + with pad group aka "nvidia,pins" cdev2 and pin mux option config aka + "nvidia,function" pllp_out4). Present if phy_type == ulpi, and ULPI link mode is in use. - resets : Must contain an entry for each entry in reset-names. See ../reset/reset.txt for details. diff --git a/Documentation/devicetree/bindings/phy/phy-mtk-xsphy.txt b/Documentation/devicetree/bindings/phy/phy-mtk-xsphy.txt new file mode 100644 index 000000000000..e7caefa0b9c2 --- /dev/null +++ b/Documentation/devicetree/bindings/phy/phy-mtk-xsphy.txt @@ -0,0 +1,109 @@ +MediaTek XS-PHY binding +-------------------------- + +The XS-PHY controller supports physical layer functionality for USB3.1 +GEN2 controller on MediaTek SoCs. + +Required properties (controller (parent) node): + - compatible : should be "mediatek,<soc-model>-xsphy", "mediatek,xsphy", + soc-model is the name of SoC, such as mt3611 etc; + when using "mediatek,xsphy" compatible string, you need SoC specific + ones in addition, one of: + - "mediatek,mt3611-xsphy" + + - #address-cells, #size-cells : should use the same values as the root node + - ranges: must be present + +Optional properties (controller (parent) node): + - reg : offset and length of register shared by multiple U3 ports, + exclude port's private register, if only U2 ports provided, + shouldn't use the property. + - mediatek,src-ref-clk-mhz : u32, frequency of reference clock for slew rate + calibrate + - mediatek,src-coef : u32, coefficient for slew rate calibrate, depends on + SoC process + +Required nodes : a sub-node is required for each port the controller + provides. Address range information including the usual + 'reg' property is used inside these nodes to describe + the controller's topology. + +Required properties (port (child) node): +- reg : address and length of the register set for the port. +- clocks : a list of phandle + clock-specifier pairs, one for each + entry in clock-names +- clock-names : must contain + "ref": 48M reference clock for HighSpeed analog phy; and 26M + reference clock for SuperSpeedPlus analog phy, sometimes is + 24M, 25M or 27M, depended on platform. +- #phy-cells : should be 1 + cell after port phandle is phy type from: + - PHY_TYPE_USB2 + - PHY_TYPE_USB3 + +The following optional properties are only for debug or HQA test +Optional properties (PHY_TYPE_USB2 port (child) node): +- mediatek,eye-src : u32, the value of slew rate calibrate +- mediatek,eye-vrt : u32, the selection of VRT reference voltage +- mediatek,eye-term : u32, the selection of HS_TX TERM reference voltage +- mediatek,efuse-intr : u32, the selection of Internal Resistor + +Optional properties (PHY_TYPE_USB3 port (child) node): +- mediatek,efuse-intr : u32, the selection of Internal Resistor +- mediatek,efuse-tx-imp : u32, the selection of TX Impedance +- mediatek,efuse-rx-imp : u32, the selection of RX Impedance + +Banks layout of xsphy +------------------------------------------------------------- +port offset bank +u2 port0 0x0000 MISC + 0x0100 FMREG + 0x0300 U2PHY_COM +u2 port1 0x1000 MISC + 0x1100 FMREG + 0x1300 U2PHY_COM +u2 port2 0x2000 MISC + ... +u31 common 0x3000 DIG_GLB + 0x3100 PHYA_GLB +u31 port0 0x3400 DIG_LN_TOP + 0x3500 DIG_LN_TX0 + 0x3600 DIG_LN_RX0 + 0x3700 DIG_LN_DAIF + 0x3800 PHYA_LN +u31 port1 0x3a00 DIG_LN_TOP + 0x3b00 DIG_LN_TX0 + 0x3c00 DIG_LN_RX0 + 0x3d00 DIG_LN_DAIF + 0x3e00 PHYA_LN + ... + +DIG_GLB & PHYA_GLB are shared by U31 ports. + +Example: + +u3phy: usb-phy@11c40000 { + compatible = "mediatek,mt3611-xsphy", "mediatek,xsphy"; + reg = <0 0x11c43000 0 0x0200>; + mediatek,src-ref-clk-mhz = <26>; + mediatek,src-coef = <17>; + #address-cells = <2>; + #size-cells = <2>; + ranges; + + u2port0: usb-phy@11c40000 { + reg = <0 0x11c40000 0 0x0400>; + clocks = <&clk48m>; + clock-names = "ref"; + mediatek,eye-src = <4>; + #phy-cells = <1>; + }; + + u3port0: usb-phy@11c43000 { + reg = <0 0x11c43400 0 0x0500>; + clocks = <&clk26m>; + clock-names = "ref"; + mediatek,efuse-intr = <28>; + #phy-cells = <1>; + }; +}; diff --git a/Documentation/devicetree/bindings/phy/qcom-qmp-phy.txt b/Documentation/devicetree/bindings/phy/qcom-qmp-phy.txt index dcf1b8f691d5..266a1bb8bb6e 100644 --- a/Documentation/devicetree/bindings/phy/qcom-qmp-phy.txt +++ b/Documentation/devicetree/bindings/phy/qcom-qmp-phy.txt @@ -9,7 +9,8 @@ Required properties: "qcom,ipq8074-qmp-pcie-phy" for PCIe phy on IPQ8074 "qcom,msm8996-qmp-pcie-phy" for 14nm PCIe phy on msm8996, "qcom,msm8996-qmp-usb3-phy" for 14nm USB3 phy on msm8996, - "qcom,qmp-v3-usb3-phy" for USB3 QMP V3 phy. + "qcom,sdm845-qmp-usb3-phy" for USB3 QMP V3 phy on sdm845, + "qcom,sdm845-qmp-usb3-uni-phy" for USB3 QMP V3 UNI phy on sdm845. - reg: offset and length of register set for PHY's common serdes block. diff --git a/Documentation/devicetree/bindings/phy/qcom-qusb2-phy.txt b/Documentation/devicetree/bindings/phy/qcom-qusb2-phy.txt index 42c97426836e..03025d97998b 100644 --- a/Documentation/devicetree/bindings/phy/qcom-qusb2-phy.txt +++ b/Documentation/devicetree/bindings/phy/qcom-qusb2-phy.txt @@ -6,7 +6,7 @@ QUSB2 controller supports LS/FS/HS usb connectivity on Qualcomm chipsets. Required properties: - compatible: compatible list, contains "qcom,msm8996-qusb2-phy" for 14nm PHY on msm8996, - "qcom,qusb2-v2-phy" for QUSB2 V2 PHY. + "qcom,sdm845-qusb2-phy" for 10nm PHY on sdm845. - reg: offset and length of the PHY register set. - #phy-cells: must be 0. @@ -27,6 +27,27 @@ Optional properties: tuning parameter value for qusb2 phy. - qcom,tcsr-syscon: Phandle to TCSR syscon register region. + - qcom,imp-res-offset-value: It is a 6 bit value that specifies offset to be + added to PHY refgen RESCODE via IMP_CTRL1 register. It is a PHY + tuning parameter that may vary for different boards of same SOC. + This property is applicable to only QUSB2 v2 PHY (sdm845). + - qcom,hstx-trim-value: It is a 4 bit value that specifies tuning for HSTX + output current. + Possible range is - 15mA to 24mA (stepsize of 600 uA). + See dt-bindings/phy/phy-qcom-qusb2.h for applicable values. + This property is applicable to only QUSB2 v2 PHY (sdm845). + Default value is 22.2mA for sdm845. + - qcom,preemphasis-level: It is a 2 bit value that specifies pre-emphasis level. + Possible range is 0 to 15% (stepsize of 5%). + See dt-bindings/phy/phy-qcom-qusb2.h for applicable values. + This property is applicable to only QUSB2 v2 PHY (sdm845). + Default value is 10% for sdm845. +- qcom,preemphasis-width: It is a 1 bit value that specifies how long the HSTX + pre-emphasis (specified using qcom,preemphasis-level) must be in + effect. Duration could be half-bit of full-bit. + See dt-bindings/phy/phy-qcom-qusb2.h for applicable values. + This property is applicable to only QUSB2 v2 PHY (sdm845). + Default value is full-bit width for sdm845. Example: hsusb_phy: phy@7411000 { diff --git a/Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt index ed5eb547afc8..64bc5c2a76da 100644 --- a/Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt +++ b/Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt @@ -56,9 +56,9 @@ pins it needs, and how they should be configured, with regard to muxer configuration, drive strength and pullups. If one of these options is not set, its actual value will be unspecified. -This driver supports the generic pin multiplexing and configuration -bindings. For details on each properties, you can refer to -./pinctrl-bindings.txt. +Allwinner A1X Pin Controller supports the generic pin multiplexing and +configuration bindings. For details on each properties, you can refer to + ./pinctrl-bindings.txt. Required sub-node properties: - pins diff --git a/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt index 2c46f30b62c5..9a06e1fdbc42 100644 --- a/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt +++ b/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt @@ -11,6 +11,7 @@ Required properies: "st,stm32f429-pinctrl" "st,stm32f469-pinctrl" "st,stm32f746-pinctrl" + "st,stm32f769-pinctrl" "st,stm32h743-pinctrl" "st,stm32mp157-pinctrl" "st,stm32mp157-z-pinctrl" diff --git a/Documentation/devicetree/bindings/pmem/pmem-region.txt b/Documentation/devicetree/bindings/pmem/pmem-region.txt new file mode 100644 index 000000000000..5cfa4f016a00 --- /dev/null +++ b/Documentation/devicetree/bindings/pmem/pmem-region.txt @@ -0,0 +1,65 @@ +Device-tree bindings for persistent memory regions +----------------------------------------------------- + +Persistent memory refers to a class of memory devices that are: + + a) Usable as main system memory (i.e. cacheable), and + b) Retain their contents across power failure. + +Given b) it is best to think of persistent memory as a kind of memory mapped +storage device. To ensure data integrity the operating system needs to manage +persistent regions separately to the normal memory pool. To aid with that this +binding provides a standardised interface for discovering where persistent +memory regions exist inside the physical address space. + +Bindings for the region nodes: +----------------------------- + +Required properties: + - compatible = "pmem-region" + + - reg = <base, size>; + The reg property should specificy an address range that is + translatable to a system physical address range. This address + range should be mappable as normal system memory would be + (i.e cacheable). + + If the reg property contains multiple address ranges + each address range will be treated as though it was specified + in a separate device node. Having multiple address ranges in a + node implies no special relationship between the two ranges. + +Optional properties: + - Any relevant NUMA assocativity properties for the target platform. + + - volatile; This property indicates that this region is actually + backed by non-persistent memory. This lets the OS know that it + may skip the cache flushes required to ensure data is made + persistent after a write. + + If this property is absent then the OS must assume that the region + is backed by non-volatile memory. + +Examples: +-------------------- + + /* + * This node specifies one 4KB region spanning from + * 0x5000 to 0x5fff that is backed by non-volatile memory. + */ + pmem@5000 { + compatible = "pmem-region"; + reg = <0x00005000 0x00001000>; + }; + + /* + * This node specifies two 4KB regions that are backed by + * volatile (normal) memory. + */ + pmem@6000 { + compatible = "pmem-region"; + reg = < 0x00006000 0x00001000 + 0x00008000 0x00001000 >; + volatile; + }; + diff --git a/Documentation/devicetree/bindings/power/power_domain.txt b/Documentation/devicetree/bindings/power/power_domain.txt index f3355313c020..4733f76cbe48 100644 --- a/Documentation/devicetree/bindings/power/power_domain.txt +++ b/Documentation/devicetree/bindings/power/power_domain.txt @@ -127,7 +127,7 @@ inside a PM domain with index 0 of a power controller represented by a node with the label "power". Optional properties: -- required-opp: This contains phandle to an OPP node in another device's OPP +- required-opps: This contains phandle to an OPP node in another device's OPP table. It may contain an array of phandles, where each phandle points to an OPP of a different device. It should not contain multiple phandles to the OPP nodes in the same OPP table. This specifies the minimum required OPP of the @@ -175,14 +175,14 @@ Example: compatible = "foo,i-leak-current"; reg = <0x12350000 0x1000>; power-domains = <&power 0>; - required-opp = <&domain0_opp_0>; + required-opps = <&domain0_opp_0>; }; leaky-device1@12350000 { compatible = "foo,i-leak-current"; reg = <0x12350000 0x1000>; power-domains = <&power 1>; - required-opp = <&domain1_opp_1>; + required-opps = <&domain1_opp_1>; }; [1]. Documentation/devicetree/bindings/power/domain-idle-state.txt diff --git a/Documentation/devicetree/bindings/power/renesas,rcar-sysc.txt b/Documentation/devicetree/bindings/power/renesas,rcar-sysc.txt index 8690f10426a3..ab399e559257 100644 --- a/Documentation/devicetree/bindings/power/renesas,rcar-sysc.txt +++ b/Documentation/devicetree/bindings/power/renesas,rcar-sysc.txt @@ -17,7 +17,9 @@ Required properties: - "renesas,r8a7794-sysc" (R-Car E2) - "renesas,r8a7795-sysc" (R-Car H3) - "renesas,r8a7796-sysc" (R-Car M3-W) + - "renesas,r8a77965-sysc" (R-Car M3-N) - "renesas,r8a77970-sysc" (R-Car V3M) + - "renesas,r8a77980-sysc" (R-Car V3H) - "renesas,r8a77995-sysc" (R-Car D3) - reg: Address start and address range for the device. - #power-domain-cells: Must be 1. diff --git a/Documentation/devicetree/bindings/power/rockchip-io-domain.txt b/Documentation/devicetree/bindings/power/rockchip-io-domain.txt index 4a4766e9c254..e66fd4eab71c 100644 --- a/Documentation/devicetree/bindings/power/rockchip-io-domain.txt +++ b/Documentation/devicetree/bindings/power/rockchip-io-domain.txt @@ -31,6 +31,8 @@ SoC is on the same page. Required properties: - compatible: should be one of: + - "rockchip,px30-io-voltage-domain" for px30 + - "rockchip,px30-pmu-io-voltage-domain" for px30 pmu-domains - "rockchip,rk3188-io-voltage-domain" for rk3188 - "rockchip,rk3228-io-voltage-domain" for rk3228 - "rockchip,rk3288-io-voltage-domain" for rk3288 @@ -51,6 +53,19 @@ a phandle the relevant regulator. All specified supplies must be able to report their voltage. The IO Voltage Domain for any non-specified supplies will be not be touched. +Possible supplies for PX30: +- vccio6-supply: The supply connected to VCCIO6. +- vccio1-supply: The supply connected to VCCIO1. +- vccio2-supply: The supply connected to VCCIO2. +- vccio3-supply: The supply connected to VCCIO3. +- vccio4-supply: The supply connected to VCCIO4. +- vccio5-supply: The supply connected to VCCIO5. +- vccio-oscgpi-supply: The supply connected to VCCIO_OSCGPI. + +Possible supplies for PX30 pmu-domains: +- pmuio1-supply: The supply connected to PMUIO1. +- pmuio2-supply: The supply connected to PMUIO2. + Possible supplies for rk3188: - ap0-supply: The supply connected to AP0_VCC. - ap1-supply: The supply connected to AP1_VCC. diff --git a/Documentation/devicetree/bindings/pwm/ingenic,jz47xx-pwm.txt b/Documentation/devicetree/bindings/pwm/ingenic,jz47xx-pwm.txt new file mode 100644 index 000000000000..7d9d3f90641b --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/ingenic,jz47xx-pwm.txt @@ -0,0 +1,25 @@ +Ingenic JZ47xx PWM Controller +============================= + +Required properties: +- compatible: One of: + * "ingenic,jz4740-pwm" + * "ingenic,jz4770-pwm" + * "ingenic,jz4780-pwm" +- #pwm-cells: Should be 3. See pwm.txt in this directory for a description + of the cells format. +- clocks : phandle to the external clock. +- clock-names : Should be "ext". + + +Example: + + pwm: pwm@10002000 { + compatible = "ingenic,jz4740-pwm"; + reg = <0x10002000 0x1000>; + + #pwm-cells = <3>; + + clocks = <&ext>; + clock-names = "ext"; + }; diff --git a/Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt b/Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt index f8338d11fd2b..bd23302e84be 100644 --- a/Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt +++ b/Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt @@ -7,6 +7,8 @@ See ../mfd/stm32-lptimer.txt for details about the parent node. Required parameters: - compatible: Must be "st,stm32-pwm-lp". +- #pwm-cells: Should be set to 3. This PWM chip uses the default 3 cells + bindings defined in pwm.txt. Optional properties: - pinctrl-names: Set to "default". @@ -18,6 +20,7 @@ Example: ... pwm { compatible = "st,stm32-pwm-lp"; + #pwm-cells = <3>; pinctrl-names = "default"; pinctrl-0 = <&lppwm1_pins>; }; diff --git a/Documentation/devicetree/bindings/pwm/pwm-sun4i.txt b/Documentation/devicetree/bindings/pwm/pwm-sun4i.txt index 51ff54c8b8ef..2a1affbff45e 100644 --- a/Documentation/devicetree/bindings/pwm/pwm-sun4i.txt +++ b/Documentation/devicetree/bindings/pwm/pwm-sun4i.txt @@ -7,6 +7,8 @@ Required properties: - "allwinner,sun5i-a13-pwm" - "allwinner,sun7i-a20-pwm" - "allwinner,sun8i-h3-pwm" + - "allwinner,sun50i-a64-pwm", "allwinner,sun5i-a13-pwm" + - "allwinner,sun50i-h5-pwm", "allwinner,sun5i-a13-pwm" - reg: physical base address and length of the controller's registers - #pwm-cells: should be 3. See pwm.txt in this directory for a description of the cells format. diff --git a/Documentation/devicetree/bindings/pwm/renesas,pwm-rcar.txt b/Documentation/devicetree/bindings/pwm/renesas,pwm-rcar.txt index 74c118015980..35a3b9761ee5 100644 --- a/Documentation/devicetree/bindings/pwm/renesas,pwm-rcar.txt +++ b/Documentation/devicetree/bindings/pwm/renesas,pwm-rcar.txt @@ -2,6 +2,8 @@ Required Properties: - compatible: should be "renesas,pwm-rcar" and one of the following. + - "renesas,pwm-r8a7743": for RZ/G1M + - "renesas,pwm-r8a7745": for RZ/G1E - "renesas,pwm-r8a7778": for R-Car M1A - "renesas,pwm-r8a7779": for R-Car H1 - "renesas,pwm-r8a7790": for R-Car H2 @@ -9,6 +11,7 @@ Required Properties: - "renesas,pwm-r8a7794": for R-Car E2 - "renesas,pwm-r8a7795": for R-Car H3 - "renesas,pwm-r8a7796": for R-Car M3-W + - "renesas,pwm-r8a77965": for R-Car M3-N - "renesas,pwm-r8a77995": for R-Car D3 - reg: base address and length of the registers block for the PWM. - #pwm-cells: should be 2. See pwm.txt in this directory for a description of @@ -17,13 +20,15 @@ Required Properties: - pinctrl-0: phandle, referring to a default pin configuration node. - pinctrl-names: Set to "default". -Example: R8A7790 (R-Car H2) PWM Timer node +Example: R8A7743 (RZ/G1M) PWM Timer node pwm0: pwm@e6e30000 { - compatible = "renesas,pwm-r8a7790", "renesas,pwm-rcar"; + compatible = "renesas,pwm-r8a7743", "renesas,pwm-rcar"; reg = <0 0xe6e30000 0 0x8>; + clocks = <&cpg CPG_MOD 523>; + power-domains = <&sysc R8A7743_PD_ALWAYS_ON>; + resets = <&cpg 523>; #pwm-cells = <2>; - clocks = <&mstp5_clks R8A7790_CLK_PWM>; pinctrl-0 = <&pwm0_pins>; pinctrl-names = "default"; }; diff --git a/Documentation/devicetree/bindings/pwm/renesas,tpu-pwm.txt b/Documentation/devicetree/bindings/pwm/renesas,tpu-pwm.txt index 1aadc804dae4..d53a16715da6 100644 --- a/Documentation/devicetree/bindings/pwm/renesas,tpu-pwm.txt +++ b/Documentation/devicetree/bindings/pwm/renesas,tpu-pwm.txt @@ -3,10 +3,12 @@ Required Properties: - compatible: should be one of the following. - - "renesas,tpu-r8a73a4": for R8A77A4 (R-Mobile APE6) compatible PWM controller. + - "renesas,tpu-r8a73a4": for R8A73A4 (R-Mobile APE6) compatible PWM controller. - "renesas,tpu-r8a7740": for R8A7740 (R-Mobile A1) compatible PWM controller. + - "renesas,tpu-r8a7743": for R8A7743 (RZ/G1M) compatible PWM controller. + - "renesas,tpu-r8a7745": for R8A7745 (RZ/G1E) compatible PWM controller. - "renesas,tpu-r8a7790": for R8A7790 (R-Car H2) compatible PWM controller. - - "renesas,tpu": for generic R-Car TPU PWM controller. + - "renesas,tpu": for generic R-Car and RZ/G1 TPU PWM controller. - reg: Base address and length of each memory resource used by the PWM controller hardware module. @@ -18,10 +20,10 @@ Required Properties: Please refer to pwm.txt in this directory for details of the common PWM bindings used by client devices. -Example: R8A7740 (R-Car A1) TPU controller node +Example: R8A7740 (R-Mobile A1) TPU controller node tpu: pwm@e6600000 { compatible = "renesas,tpu-r8a7740", "renesas,tpu"; - reg = <0xe6600000 0x100>; + reg = <0xe6600000 0x148>; #pwm-cells = <3>; }; diff --git a/Documentation/devicetree/bindings/reset/renesas,rst.txt b/Documentation/devicetree/bindings/reset/renesas,rst.txt index a8014f3ab8ba..294a0dae106a 100644 --- a/Documentation/devicetree/bindings/reset/renesas,rst.txt +++ b/Documentation/devicetree/bindings/reset/renesas,rst.txt @@ -26,7 +26,9 @@ Required properties: - "renesas,r8a7794-rst" (R-Car E2) - "renesas,r8a7795-rst" (R-Car H3) - "renesas,r8a7796-rst" (R-Car M3-W) + - "renesas,r8a77965-rst" (R-Car M3-N) - "renesas,r8a77970-rst" (R-Car V3M) + - "renesas,r8a77980-rst" (R-Car V3H) - "renesas,r8a77995-rst" (R-Car D3) - reg: Address start and address range for the device. diff --git a/Documentation/devicetree/bindings/reset/st,stm32mp1-rcc.txt b/Documentation/devicetree/bindings/reset/st,stm32mp1-rcc.txt new file mode 100644 index 000000000000..b4edaf7c7ff3 --- /dev/null +++ b/Documentation/devicetree/bindings/reset/st,stm32mp1-rcc.txt @@ -0,0 +1,6 @@ +STMicroelectronics STM32MP1 Peripheral Reset Controller +======================================================= + +The RCC IP is both a reset and a clock controller. + +Please see Documentation/devicetree/bindings/clock/st,stm32mp1-rcc.txt diff --git a/Documentation/devicetree/bindings/rtc/isil,isl12026.txt b/Documentation/devicetree/bindings/rtc/isil,isl12026.txt new file mode 100644 index 000000000000..2e0be45193bb --- /dev/null +++ b/Documentation/devicetree/bindings/rtc/isil,isl12026.txt @@ -0,0 +1,28 @@ +ISL12026 I2C RTC/EEPROM + +ISL12026 is an I2C RTC/EEPROM combination device. The RTC and control +registers respond at bus address 0x6f, and the EEPROM array responds +at bus address 0x57. The canonical "reg" value will be for the RTC portion. + +Required properties supported by the device: + + - "compatible": must be "isil,isl12026" + - "reg": I2C bus address of the device (always 0x6f) + +Optional properties: + + - "isil,pwr-bsw": If present PWR.BSW bit must be set to the specified + value for proper operation. + + - "isil,pwr-sbib": If present PWR.SBIB bit must be set to the specified + value for proper operation. + + +Example: + + rtc@6f { + compatible = "isil,isl12026"; + reg = <0x6f>; + isil,pwr-bsw = <0>; + isil,pwr-sbib = <1>; + } diff --git a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.txt b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.txt index 8ff65fa632fd..c06c045126fc 100644 --- a/Documentation/devicetree/bindings/serial/amlogic,meson-uart.txt +++ b/Documentation/devicetree/bindings/serial/amlogic,meson-uart.txt @@ -21,7 +21,7 @@ Required properties: - interrupts : identifier to the device interrupt - clocks : a list of phandle + clock-specifier pairs, one for each entry in clock names. -- clocks-names : +- clock-names : * "xtal" for external xtal clock identifier * "pclk" for the bus core clock, either the clk81 clock or the gate clock * "baud" for the source of the baudrate generator, can be either the xtal diff --git a/Documentation/devicetree/bindings/serial/mvebu-uart.txt b/Documentation/devicetree/bindings/serial/mvebu-uart.txt index 2ae2fee7e023..b7e0e32b9ac6 100644 --- a/Documentation/devicetree/bindings/serial/mvebu-uart.txt +++ b/Documentation/devicetree/bindings/serial/mvebu-uart.txt @@ -24,7 +24,7 @@ Required properties: - Must contain two elements for the extended variant of the IP (marvell,armada-3700-uart-ext): "uart-tx" and "uart-rx", respectively the UART TX interrupt and the UART RX interrupt. A - corresponding interrupts-names property must be defined. + corresponding interrupt-names property must be defined. - For backward compatibility reasons, a single element interrupts property is also supported for the standard variant of the IP, containing only the UART sum interrupt. This form is deprecated diff --git a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt index ad962f4ec3aa..106808b55b6d 100644 --- a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt +++ b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt @@ -17,6 +17,8 @@ Required properties: - "renesas,scifa-r8a7745" for R8A7745 (RZ/G1E) SCIFA compatible UART. - "renesas,scifb-r8a7745" for R8A7745 (RZ/G1E) SCIFB compatible UART. - "renesas,hscif-r8a7745" for R8A7745 (RZ/G1E) HSCIF compatible UART. + - "renesas,scif-r8a77470" for R8A77470 (RZ/G1C) SCIF compatible UART. + - "renesas,hscif-r8a77470" for R8A77470 (RZ/G1C) HSCIF compatible UART. - "renesas,scif-r8a7778" for R8A7778 (R-Car M1) SCIF compatible UART. - "renesas,scif-r8a7779" for R8A7779 (R-Car H1) SCIF compatible UART. - "renesas,scif-r8a7790" for R8A7790 (R-Car H2) SCIF compatible UART. @@ -41,6 +43,8 @@ Required properties: - "renesas,hscif-r8a7795" for R8A7795 (R-Car H3) HSCIF compatible UART. - "renesas,scif-r8a7796" for R8A7796 (R-Car M3-W) SCIF compatible UART. - "renesas,hscif-r8a7796" for R8A7796 (R-Car M3-W) HSCIF compatible UART. + - "renesas,scif-r8a77965" for R8A77965 (R-Car M3-N) SCIF compatible UART. + - "renesas,hscif-r8a77965" for R8A77965 (R-Car M3-N) HSCIF compatible UART. - "renesas,scif-r8a77970" for R8A77970 (R-Car V3M) SCIF compatible UART. - "renesas,hscif-r8a77970" for R8A77970 (R-Car V3M) HSCIF compatible UART. - "renesas,scif-r8a77980" for R8A77980 (R-Car V3H) SCIF compatible UART. diff --git a/Documentation/devicetree/bindings/soc/mediatek/scpsys.txt b/Documentation/devicetree/bindings/soc/mediatek/scpsys.txt index 76bf45b893fa..d6fe16f094af 100644 --- a/Documentation/devicetree/bindings/soc/mediatek/scpsys.txt +++ b/Documentation/devicetree/bindings/soc/mediatek/scpsys.txt @@ -21,6 +21,8 @@ Required properties: - "mediatek,mt2712-scpsys" - "mediatek,mt6797-scpsys" - "mediatek,mt7622-scpsys" + - "mediatek,mt7623-scpsys", "mediatek,mt2701-scpsys": For MT7623 SoC + - "mediatek,mt7623a-scpsys": For MT7623A SoC - "mediatek,mt8173-scpsys" - #power-domain-cells: Must be 1 - reg: Address range of the SCPSYS unit @@ -28,10 +30,11 @@ Required properties: - clock, clock-names: clocks according to the common clock binding. These are clocks which hardware needs to be enabled before enabling certain power domains. - Required clocks for MT2701: "mm", "mfg", "ethif" + Required clocks for MT2701 or MT7623: "mm", "mfg", "ethif" Required clocks for MT2712: "mm", "mfg", "venc", "jpgdec", "audio", "vdec" Required clocks for MT6797: "mm", "mfg", "vdec" Required clocks for MT7622: "hif_sel" + Required clocks for MT7622A: "ethif" Required clocks for MT8173: "mm", "mfg", "venc", "venc_lt" Optional properties: diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,apr.txt b/Documentation/devicetree/bindings/soc/qcom/qcom,apr.txt new file mode 100644 index 000000000000..bcc612cc7423 --- /dev/null +++ b/Documentation/devicetree/bindings/soc/qcom/qcom,apr.txt @@ -0,0 +1,84 @@ +Qualcomm APR (Asynchronous Packet Router) binding + +This binding describes the Qualcomm APR. APR is a IPC protocol for +communication between Application processor and QDSP. APR is mainly +used for audio/voice services on the QDSP. + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be "qcom,apr-v<VERSION-NUMBER>", example "qcom,apr-v2" + +- reg + Usage: required + Value type: <u32> + Definition: Destination processor ID. + Possible values are : + 1 - APR simulator + 2 - PC + 3 - MODEM + 4 - ADSP + 5 - APPS + 6 - MODEM2 + 7 - APPS2 + += APR SERVICES +Each subnode of the APR node represents service tied to this apr. The name +of the nodes are not important. The properties of these nodes are defined +by the individual bindings for the specific service +- All APR services MUST contain the following property: + +- reg + Usage: required + Value type: <u32> + Definition: APR Service ID + Possible values are : + 3 - DSP Core Service + 4 - Audio Front End Service. + 5 - Voice Stream Manager Service. + 6 - Voice processing manager. + 7 - Audio Stream Manager Service. + 8 - Audio Device Manager Service. + 9 - Multimode voice manager. + 10 - Core voice stream. + 11 - Core voice processor. + 12 - Ultrasound stream manager. + 13 - Listen stream manager. + += EXAMPLE +The following example represents a QDSP based sound card on a MSM8996 device +which uses apr as communication between Apps and QDSP. + + apr@4 { + compatible = "qcom,apr-v2"; + reg = <APR_DOMAIN_ADSP>; + + q6core@3 { + compatible = "qcom,q6core"; + reg = <APR_SVC_ADSP_CORE>; + }; + + q6afe@4 { + compatible = "qcom,q6afe"; + reg = <APR_SVC_AFE>; + + dais { + #sound-dai-cells = <1>; + hdmi@1 { + reg = <1>; + }; + }; + }; + + q6asm@7 { + compatible = "qcom,q6asm"; + reg = <APR_SVC_ASM>; + ... + }; + + q6adm@8 { + compatible = "qcom,q6adm"; + reg = <APR_SVC_ADM>; + ... + }; + }; diff --git a/Documentation/devicetree/bindings/sound/adi,ssm2305.txt b/Documentation/devicetree/bindings/sound/adi,ssm2305.txt new file mode 100644 index 000000000000..a9c9d83c8a30 --- /dev/null +++ b/Documentation/devicetree/bindings/sound/adi,ssm2305.txt @@ -0,0 +1,14 @@ +Analog Devices SSM2305 Speaker Amplifier +======================================== + +Required properties: + - compatible : "adi,ssm2305" + - shutdown-gpios : The gpio connected to the shutdown pin. + The gpio signal is ACTIVE_LOW. + +Example: + +ssm2305: analog-amplifier { + compatible = "adi,ssm2305"; + shutdown-gpios = <&gpio3 20 GPIO_ACTIVE_LOW>; +}; diff --git a/Documentation/devicetree/bindings/sound/atmel-i2s.txt b/Documentation/devicetree/bindings/sound/atmel-i2s.txt new file mode 100644 index 000000000000..735368b8a73f --- /dev/null +++ b/Documentation/devicetree/bindings/sound/atmel-i2s.txt @@ -0,0 +1,47 @@ +* Atmel I2S controller + +Required properties: +- compatible: Should be "atmel,sama5d2-i2s". +- reg: Should be the physical base address of the controller and the + length of memory mapped region. +- interrupts: Should contain the interrupt for the controller. +- dmas: Should be one per channel name listed in the dma-names property, + as described in atmel-dma.txt and dma.txt files. +- dma-names: Two dmas have to be defined, "tx" and "rx". + This IP also supports one shared channel for both rx and tx; + if this mode is used, one "rx-tx" name must be used. +- clocks: Must contain an entry for each entry in clock-names. + Please refer to clock-bindings.txt. +- clock-names: Should be one of each entry matching the clocks phandles list: + - "pclk" (peripheral clock) Required. + - "gclk" (generated clock) Optional (1). + - "aclk" (Audio PLL clock) Optional (1). + - "muxclk" (I2S mux clock) Optional (1). + +Optional properties: +- pinctrl-0: Should specify pin control groups used for this controller. +- princtrl-names: Should contain only one value - "default". + + +(1) : Only the peripheral clock is required. The generated clock, the Audio + PLL clock adn the I2S mux clock are optional and should only be set + together, when Master Mode is required. + +Example: + + i2s@f8050000 { + compatible = "atmel,sama5d2-i2s"; + reg = <0xf8050000 0x300>; + interrupts = <54 IRQ_TYPE_LEVEL_HIGH 7>; + dmas = <&dma0 + (AT91_XDMAC_DT_MEM_IF(0) | AT91_XDMAC_DT_PER_IF(1) | + AT91_XDMAC_DT_PERID(31))>, + <&dma0 + (AT91_XDMAC_DT_MEM_IF(0) | AT91_XDMAC_DT_PER_IF(1) | + AT91_XDMAC_DT_PERID(32))>; + dma-names = "tx", "rx"; + clocks = <&i2s0_clk>, <&i2s0_gclk>, <&audio_pll_pmc>, <&i2s0muxck>; + clock-names = "pclk", "gclk", "aclk", "muxclk"; + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_i2s0_default>; + }; diff --git a/Documentation/devicetree/bindings/sound/brcm,bcm2835-i2s.txt b/Documentation/devicetree/bindings/sound/brcm,bcm2835-i2s.txt index 65783de0aedf..7bb0362828ec 100644 --- a/Documentation/devicetree/bindings/sound/brcm,bcm2835-i2s.txt +++ b/Documentation/devicetree/bindings/sound/brcm,bcm2835-i2s.txt @@ -2,9 +2,8 @@ Required properties: - compatible: "brcm,bcm2835-i2s" -- reg: A list of base address and size entries: - * The first entry should cover the PCM registers - * The second entry should cover the PCM clock registers +- reg: Should contain PCM registers location and length. +- clocks: the (PCM) clock to use - dmas: List of DMA controller phandle and DMA request line ordered pairs. - dma-names: Identifier string for each DMA request line in the dmas property. These strings correspond 1:1 with the ordered pairs in dmas. @@ -16,8 +15,8 @@ Example: bcm2835_i2s: i2s@7e203000 { compatible = "brcm,bcm2835-i2s"; - reg = <0x7e203000 0x20>, - <0x7e101098 0x02>; + reg = <0x7e203000 0x24>; + clocks = <&clocks BCM2835_CLOCK_PCM>; dmas = <&dma 2>, <&dma 3>; diff --git a/Documentation/devicetree/bindings/sound/cs42xx8.txt b/Documentation/devicetree/bindings/sound/cs42xx8.txt index f631fbca6284..8619a156d038 100644 --- a/Documentation/devicetree/bindings/sound/cs42xx8.txt +++ b/Documentation/devicetree/bindings/sound/cs42xx8.txt @@ -16,7 +16,7 @@ Required properties: Example: -codec: cs42888@48 { +cs42888: codec@48 { compatible = "cirrus,cs42888"; reg = <0x48>; clocks = <&codec_mclk 0>; diff --git a/Documentation/devicetree/bindings/sound/fsl,asrc.txt b/Documentation/devicetree/bindings/sound/fsl,asrc.txt index f5a14115b459..1d4d9f938689 100644 --- a/Documentation/devicetree/bindings/sound/fsl,asrc.txt +++ b/Documentation/devicetree/bindings/sound/fsl,asrc.txt @@ -31,14 +31,16 @@ Required properties: it. This property is optional depending on the SoC design. - - big-endian : If this property is absent, the little endian mode - will be in use as default. Otherwise, the big endian - mode will be in use for all the device registers. - - fsl,asrc-rate : Defines a mutual sample rate used by DPCM Back Ends. - fsl,asrc-width : Defines a mutual sample width used by DPCM Back Ends. +Optional properties: + + - big-endian : If this property is absent, the little endian mode + will be in use as default. Otherwise, the big endian + mode will be in use for all the device registers. + Example: asrc: asrc@2034000 { diff --git a/Documentation/devicetree/bindings/sound/fsl,esai.txt b/Documentation/devicetree/bindings/sound/fsl,esai.txt index cacd18bb9ba6..5b9914367610 100644 --- a/Documentation/devicetree/bindings/sound/fsl,esai.txt +++ b/Documentation/devicetree/bindings/sound/fsl,esai.txt @@ -42,6 +42,8 @@ Required properties: means all the settings for Receiving would be duplicated from Transmition related registers. +Optional properties: + - big-endian : If this property is absent, the native endian mode will be in use as default, or the big endian mode will be in use for all the device registers. diff --git a/Documentation/devicetree/bindings/sound/fsl,spdif.txt b/Documentation/devicetree/bindings/sound/fsl,spdif.txt index 38cfa7573441..8b324f82a782 100644 --- a/Documentation/devicetree/bindings/sound/fsl,spdif.txt +++ b/Documentation/devicetree/bindings/sound/fsl,spdif.txt @@ -33,6 +33,8 @@ Required properties: it. This property is optional depending on the SoC design. +Optional properties: + - big-endian : If this property is absent, the native endian mode will be in use as default, or the big endian mode will be in use for all the device registers. diff --git a/Documentation/devicetree/bindings/sound/fsl-sai.txt b/Documentation/devicetree/bindings/sound/fsl-sai.txt index 740b467adf7d..dd9e59738e08 100644 --- a/Documentation/devicetree/bindings/sound/fsl-sai.txt +++ b/Documentation/devicetree/bindings/sound/fsl-sai.txt @@ -28,9 +28,6 @@ Required properties: pinctrl-names. See ../pinctrl/pinctrl-bindings.txt for details of the property values. - - big-endian : Boolean property, required if all the FTM_PWM - registers are big-endian rather than little-endian. - - lsb-first : Configures whether the LSB or the MSB is transmitted first for the fifo data. If this property is absent, the MSB is transmitted first as default, or the LSB @@ -48,6 +45,11 @@ Required properties: receive data by following their own bit clocks and frame sync clocks separately. +Optional properties: + + - big-endian : Boolean property, required if all the SAI + registers are big-endian rather than little-endian. + Optional properties (for mx6ul): - fsl,sai-mclk-direction-output: This is a boolean property. If present, diff --git a/Documentation/devicetree/bindings/sound/mt2701-afe-pcm.txt b/Documentation/devicetree/bindings/sound/mt2701-afe-pcm.txt index e2f7f4951215..560762e0a168 100644 --- a/Documentation/devicetree/bindings/sound/mt2701-afe-pcm.txt +++ b/Documentation/devicetree/bindings/sound/mt2701-afe-pcm.txt @@ -1,7 +1,9 @@ Mediatek AFE PCM controller for mt2701 Required properties: -- compatible = "mediatek,mt2701-audio"; +- compatible: should be one of the followings. + - "mediatek,mt2701-audio" + - "mediatek,mt7622-audio" - interrupts: should contain AFE and ASYS interrupts - interrupt-names: should be "afe" and "asys" - power-domains: should define the power domain diff --git a/Documentation/devicetree/bindings/sound/mt6351.txt b/Documentation/devicetree/bindings/sound/mt6351.txt new file mode 100644 index 000000000000..7fb2cb99245e --- /dev/null +++ b/Documentation/devicetree/bindings/sound/mt6351.txt @@ -0,0 +1,16 @@ +Mediatek MT6351 Audio Codec + +The communication between MT6351 and SoC is through Mediatek PMIC wrapper. +For more detail, please visit Mediatek PMIC wrapper documentation. + +Must be a child node of PMIC wrapper. + +Required properties: + +- compatible : "mediatek,mt6351-sound". + +Example: + +mt6351_snd { + compatible = "mediatek,mt6351-sound"; +}; diff --git a/Documentation/devicetree/bindings/sound/mt6797-afe-pcm.txt b/Documentation/devicetree/bindings/sound/mt6797-afe-pcm.txt new file mode 100644 index 000000000000..0ae29de15bfd --- /dev/null +++ b/Documentation/devicetree/bindings/sound/mt6797-afe-pcm.txt @@ -0,0 +1,42 @@ +Mediatek AFE PCM controller for mt6797 + +Required properties: +- compatible = "mediatek,mt6797-audio"; +- reg: register location and size +- interrupts: should contain AFE interrupt +- power-domains: should define the power domain +- clocks: Must contain an entry for each entry in clock-names +- clock-names: should have these clock names: + "infra_sys_audio_clk", + "infra_sys_audio_26m", + "mtkaif_26m_clk", + "top_mux_audio", + "top_mux_aud_intbus", + "top_sys_pll3_d4", + "top_sys_pll1_d4", + "top_clk26m_clk"; + +Example: + + afe: mt6797-afe-pcm@11220000 { + compatible = "mediatek,mt6797-audio"; + reg = <0 0x11220000 0 0x1000>; + interrupts = <GIC_SPI 151 IRQ_TYPE_LEVEL_LOW>; + power-domains = <&scpsys MT6797_POWER_DOMAIN_AUDIO>; + clocks = <&infrasys CLK_INFRA_AUDIO>, + <&infrasys CLK_INFRA_AUDIO_26M>, + <&infrasys CLK_INFRA_AUDIO_26M_PAD_TOP>, + <&topckgen CLK_TOP_MUX_AUDIO>, + <&topckgen CLK_TOP_MUX_AUD_INTBUS>, + <&topckgen CLK_TOP_SYSPLL3_D4>, + <&topckgen CLK_TOP_SYSPLL1_D4>, + <&clk26m>; + clock-names = "infra_sys_audio_clk", + "infra_sys_audio_26m", + "mtkaif_26m_clk", + "top_mux_audio", + "top_mux_aud_intbus", + "top_sys_pll3_d4", + "top_sys_pll1_d4", + "top_clk26m_clk"; + }; diff --git a/Documentation/devicetree/bindings/sound/mt6797-mt6351.txt b/Documentation/devicetree/bindings/sound/mt6797-mt6351.txt new file mode 100644 index 000000000000..1d95a8840f19 --- /dev/null +++ b/Documentation/devicetree/bindings/sound/mt6797-mt6351.txt @@ -0,0 +1,14 @@ +MT6797 with MT6351 CODEC + +Required properties: +- compatible: "mediatek,mt6797-mt6351-sound" +- mediatek,platform: the phandle of MT6797 ASoC platform +- mediatek,audio-codec: the phandles of MT6351 codec + +Example: + + sound { + compatible = "mediatek,mt6797-mt6351-sound"; + mediatek,audio-codec = <&mt6351_snd>; + mediatek,platform = <&afe>; + }; diff --git a/Documentation/devicetree/bindings/sound/qcom,apq8096.txt b/Documentation/devicetree/bindings/sound/qcom,apq8096.txt new file mode 100644 index 000000000000..aa54e49fc8a2 --- /dev/null +++ b/Documentation/devicetree/bindings/sound/qcom,apq8096.txt @@ -0,0 +1,109 @@ +* Qualcomm Technologies APQ8096 ASoC sound card driver + +This binding describes the APQ8096 sound card, which uses qdsp for audio. + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be "qcom,apq8096-sndcard" + +- qcom,audio-routing: + Usage: Optional + Value type: <stringlist> + Definition: A list of the connections between audio components. + Each entry is a pair of strings, the first being the + connection's sink, the second being the connection's + source. Valid names could be power supplies, MicBias + of codec and the jacks on the board: + Valid names include: + + Board Connectors: + "Headphone Left" + "Headphone Right" + "Earphone" + "Line Out1" + "Line Out2" + "Line Out3" + "Line Out4" + "Analog Mic1" + "Analog Mic2" + "Analog Mic3" + "Analog Mic4" + "Analog Mic5" + "Analog Mic6" + "Digital Mic2" + "Digital Mic3" + + Audio pins and MicBias on WCD9335 Codec: + "MIC_BIAS1 + "MIC_BIAS2" + "MIC_BIAS3" + "MIC_BIAS4" + "AMIC1" + "AMIC2" + "AMIC3" + "AMIC4" + "AMIC5" + "AMIC6" + "AMIC6" + "DMIC1" + "DMIC2" + "DMIC3" += dailinks +Each subnode of sndcard represents either a dailink, and subnodes of each +dailinks would be cpu/codec/platform dais. + +- link-name: + Usage: required + Value type: <string> + Definition: User friendly name for dai link + += CPU, PLATFORM, CODEC dais subnodes +- cpu: + Usage: required + Value type: <subnode> + Definition: cpu dai sub-node + +- codec: + Usage: Optional + Value type: <subnode> + Definition: codec dai sub-node + +- platform: + Usage: Optional + Value type: <subnode> + Definition: platform dai sub-node + +- sound-dai: + Usage: required + Value type: <phandle with arguments> + Definition: dai phandle/s and port of CPU/CODEC/PLATFORM node. + +Example: + +audio { + compatible = "qcom,apq8096-sndcard"; + qcom,model = "DB820c"; + + mm1-dai-link { + link-name = "MultiMedia1"; + cpu { + sound-dai = <&q6asmdai MSM_FRONTEND_DAI_MULTIMEDIA1>; + }; + }; + + hdmi-dai-link { + link-name = "HDMI Playback"; + cpu { + sound-dai = <&q6afe HDMI_RX>; + }; + + platform { + sound-dai = <&q6adm>; + }; + + codec { + sound-dai = <&hdmi 0>; + }; + }; +}; diff --git a/Documentation/devicetree/bindings/sound/qcom,q6adm.txt b/Documentation/devicetree/bindings/sound/qcom,q6adm.txt new file mode 100644 index 000000000000..cb709e5dbc44 --- /dev/null +++ b/Documentation/devicetree/bindings/sound/qcom,q6adm.txt @@ -0,0 +1,33 @@ +Qualcomm Audio Device Manager (Q6ADM) binding + +Q6ADM is one of the APR audio service on Q6DSP. +Please refer to qcom,apr.txt for details of the coommon apr service bindings +used by the apr service device. + +- but must contain the following property: + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be "qcom,q6adm-v<MAJOR-NUMBER>.<MINOR-NUMBER>". + Or "qcom,q6adm" where the version number can be queried + from DSP. + example "qcom,q6adm-v2.0" + + += ADM routing +"routing" subnode of the ADM node represents adm routing specific configuration + +- #sound-dai-cells + Usage: required + Value type: <u32> + Definition: Must be 0 + += EXAMPLE +q6adm@8 { + compatible = "qcom,q6adm"; + reg = <APR_SVC_ADM>; + q6routing: routing { + #sound-dai-cells = <0>; + }; +}; diff --git a/Documentation/devicetree/bindings/sound/qcom,q6afe.txt b/Documentation/devicetree/bindings/sound/qcom,q6afe.txt new file mode 100644 index 000000000000..bdbf87df8c0b --- /dev/null +++ b/Documentation/devicetree/bindings/sound/qcom,q6afe.txt @@ -0,0 +1,172 @@ +Qualcomm Audio Front End (Q6AFE) binding + +AFE is one of the APR audio service on Q6DSP +Please refer to qcom,apr.txt for details of the common apr service bindings +used by all apr services. Must contain the following properties. + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be "qcom,q6afe-v<MAJOR-NUMBER>.<MINOR-NUMBER>" + Or "qcom,q6afe" where the version number can be queried + from DSP. + example "qcom,q6afe" + += AFE DAIs (Digial Audio Interface) +"dais" subnode of the AFE node. It represents afe dais, each afe dai is a +subnode of "dais" representing board specific dai setup. +"dais" node should have following properties followed by dai children. + +- #sound-dai-cells + Usage: required + Value type: <u32> + Definition: Must be 1 + +- #address-cells + Usage: required + Value type: <u32> + Definition: Must be 1 + +- #size-cells + Usage: required + Value type: <u32> + Definition: Must be 0 + +== AFE DAI is subnode of "dais" and represent a dai, it includes board specific +configuration of each dai. Must contain the following properties. + +- reg + Usage: required + Value type: <u32> + Definition: Must be dai id + +- qcom,sd-lines + Usage: required for mi2s interface + Value type: <prop-encoded-array> + Definition: Must be list of serial data lines used by this dai. + should be one or more of the 1-4 sd lines. + + - qcom,tdm-sync-mode: + Usage: required for tdm interface + Value type: <prop-encoded-array> + Definition: Synchronization mode. + 0 - Short sync bit mode + 1 - Long sync mode + 2 - Short sync slot mode + + - qcom,tdm-sync-src: + Usage: required for tdm interface + Value type: <prop-encoded-array> + Definition: Synchronization source. + 0 - External source + 1 - Internal source + + - qcom,tdm-data-out: + Usage: required for tdm interface + Value type: <prop-encoded-array> + Definition: Data out signal to drive with other masters. + 0 - Disable + 1 - Enable + + - qcom,tdm-invert-sync: + Usage: required for tdm interface + Value type: <prop-encoded-array> + Definition: Invert the sync. + 0 - Normal + 1 - Invert + + - qcom,tdm-data-delay: + Usage: required for tdm interface + Value type: <prop-encoded-array> + Definition: Number of bit clock to delay data + with respect to sync edge. + 0 - 0 bit clock cycle + 1 - 1 bit clock cycle + 2 - 2 bit clock cycle + + - qcom,tdm-data-align: + Usage: required for tdm interface + Value type: <prop-encoded-array> + Definition: Indicate how data is packed + within the slot. For example, 32 slot width in case of + sample bit width is 24. + 0 - MSB + 1 - LSB + += EXAMPLE + +q6afe@4 { + compatible = "qcom,q6afe"; + reg = <APR_SVC_AFE>; + + dais { + #sound-dai-cells = <1>; + #address-cells = <1>; + #size-cells = <0>; + + hdmi@1 { + reg = <1>; + }; + + tdm@24 { + reg = <24>; + qcom,tdm-sync-mode = <1>: + qcom,tdm-sync-src = <1>; + qcom,tdm-data-out = <0>; + qcom,tdm-invert-sync = <1>; + qcom,tdm-data-delay = <1>; + qcom,tdm-data-align = <0>; + + }; + + tdm@25 { + reg = <25>; + qcom,tdm-sync-mode = <1>: + qcom,tdm-sync-src = <1>; + qcom,tdm-data-out = <0>; + qcom,tdm-invert-sync = <1>; + qcom,tdm-data-delay <1>: + qcom,tdm-data-align = <0>; + }; + + prim-mi2s-rx@16 { + reg = <16>; + qcom,sd-lines = <1 3>; + }; + + prim-mi2s-tx@17 { + reg = <17>; + qcom,sd-lines = <2>; + }; + + sec-mi2s-rx@18 { + reg = <18>; + qcom,sd-lines = <1 4>; + }; + + sec-mi2s-tx@19 { + reg = <19>; + qcom,sd-lines = <2>; + }; + + tert-mi2s-rx@20 { + reg = <20>; + qcom,sd-lines = <2 4>; + }; + + tert-mi2s-tx@21 { + reg = <21>; + qcom,sd-lines = <1>; + }; + + quat-mi2s-rx@22 { + reg = <22>; + qcom,sd-lines = <1>; + }; + + quat-mi2s-tx@23 { + reg = <23>; + qcom,sd-lines = <2>; + }; + }; +}; diff --git a/Documentation/devicetree/bindings/sound/qcom,q6asm.txt b/Documentation/devicetree/bindings/sound/qcom,q6asm.txt new file mode 100644 index 000000000000..2178eb91146f --- /dev/null +++ b/Documentation/devicetree/bindings/sound/qcom,q6asm.txt @@ -0,0 +1,33 @@ +Qualcomm Audio Stream Manager (Q6ASM) binding + +Q6ASM is one of the APR audio service on Q6DSP. +Please refer to qcom,apr.txt for details of the common apr service bindings +used by the apr service device. + +- but must contain the following property: + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be "qcom,q6asm-v<MAJOR-NUMBER>.<MINOR-NUMBER>". + Or "qcom,q6asm" where the version number can be queried + from DSP. + example "qcom,q6asm-v2.0" + += ASM DAIs (Digial Audio Interface) +"dais" subnode of the ASM node represents dai specific configuration + +- #sound-dai-cells + Usage: required + Value type: <u32> + Definition: Must be 1 + += EXAMPLE + +q6asm@7 { + compatible = "qcom,q6asm"; + reg = <APR_SVC_ASM>; + q6asmdai: dais { + #sound-dai-cells = <1>; + }; +}; diff --git a/Documentation/devicetree/bindings/sound/qcom,q6core.txt b/Documentation/devicetree/bindings/sound/qcom,q6core.txt new file mode 100644 index 000000000000..7f36ff8bec18 --- /dev/null +++ b/Documentation/devicetree/bindings/sound/qcom,q6core.txt @@ -0,0 +1,21 @@ +Qualcomm ADSP Core service binding + +Q6CORE is one of the APR audio service on Q6DSP. +Please refer to qcom,apr.txt for details of the common apr service bindings +used by the apr service device. + +- but must contain the following property: + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be "qcom,q6core-v<MAJOR-NUMBER>.<MINOR-NUMBER>". + Or "qcom,q6core" where the version number can be queried + from DSP. + example "qcom,q6core-v2.0" + += EXAMPLE +q6core@3 { + compatible = "qcom,q6core"; + reg = <APR_SVC_ADSP_CORE>; +}; diff --git a/Documentation/devicetree/bindings/sound/rt274.txt b/Documentation/devicetree/bindings/sound/rt274.txt index e9a6178c78cf..791a1bd767b9 100644 --- a/Documentation/devicetree/bindings/sound/rt274.txt +++ b/Documentation/devicetree/bindings/sound/rt274.txt @@ -26,7 +26,7 @@ Pins on the device (for linking into audio routes) for RT274: Example: -codec: rt274@1c { +rt274: codec@1c { compatible = "realtek,rt274"; reg = <0x1c>; interrupts = <7 IRQ_TYPE_EDGE_FALLING>; diff --git a/Documentation/devicetree/bindings/sound/rt5514.txt b/Documentation/devicetree/bindings/sound/rt5514.txt index 4f33b0d96afe..b25ed08c7a5a 100644 --- a/Documentation/devicetree/bindings/sound/rt5514.txt +++ b/Documentation/devicetree/bindings/sound/rt5514.txt @@ -32,7 +32,7 @@ Pins on the device (for linking into audio routes) for I2C: Example: -codec: rt5514@57 { +rt5514: codec@57 { compatible = "realtek,rt5514"; reg = <0x57>; }; diff --git a/Documentation/devicetree/bindings/sound/rt5616.txt b/Documentation/devicetree/bindings/sound/rt5616.txt index e41085818559..540a4bf252e4 100644 --- a/Documentation/devicetree/bindings/sound/rt5616.txt +++ b/Documentation/devicetree/bindings/sound/rt5616.txt @@ -26,7 +26,7 @@ Pins on the device (for linking into audio routes) for RT5616: Example: -codec: rt5616@1b { +rt5616: codec@1b { compatible = "realtek,rt5616"; reg = <0x1b>; }; diff --git a/Documentation/devicetree/bindings/sound/rt5640.txt b/Documentation/devicetree/bindings/sound/rt5640.txt index 57fe64643050..e40e4893eed8 100644 --- a/Documentation/devicetree/bindings/sound/rt5640.txt +++ b/Documentation/devicetree/bindings/sound/rt5640.txt @@ -22,6 +22,41 @@ Optional properties: - realtek,ldo1-en-gpios : The GPIO that controls the CODEC's LDO1_EN pin. +- realtek,dmic1-data-pin + 0: dmic1 is not used + 1: using IN1P pin as dmic1 data pin + 2: using GPIO3 pin as dmic1 data pin + +- realtek,dmic2-data-pin + 0: dmic2 is not used + 1: using IN1N pin as dmic2 data pin + 2: using GPIO4 pin as dmic2 data pin + +- realtek,jack-detect-source + u32. Valid values: + 0: jack-detect is not used + 1: Use GPIO1 for jack-detect + 2: Use JD1_IN4P for jack-detect + 3: Use JD2_IN4N for jack-detect + 4: Use GPIO2 for jack-detect + 5: Use GPIO3 for jack-detect + 6: Use GPIO4 for jack-detect + +- realtek,jack-detect-not-inverted + bool. Normal jack-detect switches give an inverted signal, set this bool + in the rare case you've a jack-detect switch which is not inverted. + +- realtek,over-current-threshold-microamp + u32, micbias over-current detection threshold in µA, valid values are + 600, 1500 and 2000µA. + +- realtek,over-current-scale-factor + u32, micbias over-current detection scale-factor, valid values are: + 0: Scale current by 0.5 + 1: Scale current by 0.75 + 2: Scale current by 1.0 + 3: Scale current by 1.5 + Pins on the device (for linking into audio routes) for RT5639/RT5640: * DMIC1 diff --git a/Documentation/devicetree/bindings/sound/rt5645.txt b/Documentation/devicetree/bindings/sound/rt5645.txt index 7cee1f518f59..a03f9a872a71 100644 --- a/Documentation/devicetree/bindings/sound/rt5645.txt +++ b/Documentation/devicetree/bindings/sound/rt5645.txt @@ -69,4 +69,4 @@ codec: rt5650@1a { realtek,dmic-en = "true"; realtek,en-jd-func = "true"; realtek,jd-mode = <3>; -};
\ No newline at end of file +}; diff --git a/Documentation/devicetree/bindings/sound/rt5651.txt b/Documentation/devicetree/bindings/sound/rt5651.txt index b85221864cec..a41199a5cd79 100644 --- a/Documentation/devicetree/bindings/sound/rt5651.txt +++ b/Documentation/devicetree/bindings/sound/rt5651.txt @@ -50,7 +50,7 @@ Pins on the device (for linking into audio routes) for RT5651: Example: -codec: rt5651@1a { +rt5651: codec@1a { compatible = "realtek,rt5651"; reg = <0x1a>; realtek,dmic-en = "true"; diff --git a/Documentation/devicetree/bindings/sound/rt5663.txt b/Documentation/devicetree/bindings/sound/rt5663.txt index 497bcfc58b71..23386446c63d 100644 --- a/Documentation/devicetree/bindings/sound/rt5663.txt +++ b/Documentation/devicetree/bindings/sound/rt5663.txt @@ -47,7 +47,7 @@ Pins on the device (for linking into audio routes) for RT5663: Example: -codec: rt5663@12 { +rt5663: codec@12 { compatible = "realtek,rt5663"; reg = <0x12>; interrupts = <7 IRQ_TYPE_EDGE_FALLING>; diff --git a/Documentation/devicetree/bindings/sound/rt5668.txt b/Documentation/devicetree/bindings/sound/rt5668.txt new file mode 100644 index 000000000000..c88b96e7764b --- /dev/null +++ b/Documentation/devicetree/bindings/sound/rt5668.txt @@ -0,0 +1,50 @@ +RT5668B audio CODEC + +This device supports I2C only. + +Required properties: + +- compatible : "realtek,rt5668b" + +- reg : The I2C address of the device. + +Optional properties: + +- interrupts : The CODEC's interrupt output. + +- realtek,dmic1-data-pin + 0: dmic1 is not used + 1: using GPIO2 pin as dmic1 data pin + 2: using GPIO5 pin as dmic1 data pin + +- realtek,dmic1-clk-pin + 0: using GPIO1 pin as dmic1 clock pin + 1: using GPIO3 pin as dmic1 clock pin + +- realtek,jd-src + 0: No JD is used + 1: using JD1 as JD source + +- realtek,ldo1-en-gpios : The GPIO that controls the CODEC's LDO1_EN pin. + +Pins on the device (for linking into audio routes) for RT5668B: + + * DMIC L1 + * DMIC R1 + * IN1P + * HPOL + * HPOR + +Example: + +rt5668 { + compatible = "realtek,rt5668b"; + reg = <0x1a>; + interrupt-parent = <&gpio>; + interrupts = <TEGRA_GPIO(U, 6) GPIO_ACTIVE_HIGH>; + realtek,ldo1-en-gpios = + <&gpio TEGRA_GPIO(R, 2) GPIO_ACTIVE_HIGH>; + realtek,dmic1-data-pin = <1>; + realtek,dmic1-clk-pin = <1>; + realtek,jd-src = <1>; +}; diff --git a/Documentation/devicetree/bindings/sound/sgtl5000.txt b/Documentation/devicetree/bindings/sound/sgtl5000.txt index 9a36c7e2a143..0f214457476f 100644 --- a/Documentation/devicetree/bindings/sound/sgtl5000.txt +++ b/Documentation/devicetree/bindings/sound/sgtl5000.txt @@ -39,7 +39,7 @@ VDDIO 1.8V 2.5V 3.3V Example: -codec: sgtl5000@a { +sgtl5000: codec@a { compatible = "fsl,sgtl5000"; reg = <0x0a>; #sound-dai-cells = <0>; diff --git a/Documentation/devicetree/bindings/sound/simple-card.txt b/Documentation/devicetree/bindings/sound/simple-card.txt index 17c13e74667d..a4c72d09cd45 100644 --- a/Documentation/devicetree/bindings/sound/simple-card.txt +++ b/Documentation/devicetree/bindings/sound/simple-card.txt @@ -86,6 +86,11 @@ Optional CPU/CODEC subnodes properties: in dai startup() and disabled with clk_disable_unprepare() in dai shutdown(). + If a clock is specified and a + multiplication factor is given with + mclk-fs, the clock will be set to the + calculated mclk frequency when the + stream starts. - system-clock-direction-out : specifies clock direction as 'out' on initialization. It is useful for some aCPUs with fixed clocks. diff --git a/Documentation/devicetree/bindings/sound/ti,tas6424.txt b/Documentation/devicetree/bindings/sound/ti,tas6424.txt index 1c4ada0eef4e..eacb54f34188 100644 --- a/Documentation/devicetree/bindings/sound/ti,tas6424.txt +++ b/Documentation/devicetree/bindings/sound/ti,tas6424.txt @@ -6,6 +6,8 @@ Required properties: - compatible: "ti,tas6424" - TAS6424 - reg: I2C slave address - sound-dai-cells: must be equal to 0 + - standby-gpios: GPIO used to shut the TAS6424 down. + - mute-gpios: GPIO used to mute all the outputs Example: diff --git a/Documentation/devicetree/bindings/sound/tscs42xx.txt b/Documentation/devicetree/bindings/sound/tscs42xx.txt index 2ac2f0996697..7eea32e9d078 100644 --- a/Documentation/devicetree/bindings/sound/tscs42xx.txt +++ b/Documentation/devicetree/bindings/sound/tscs42xx.txt @@ -8,9 +8,15 @@ Required Properties: - reg : <0x71> for analog mic <0x69> for digital mic + - clock-names: Must one of the following "mclk1", "xtal", "mclk2" + + - clocks: phandle of the clock that provides the codec sysclk + Example: wookie: codec@69 { compatible = "tempo,tscs42A2"; reg = <0x69>; + clock-names = "xtal"; + clocks = <&audio_xtal>; }; diff --git a/Documentation/devicetree/bindings/sound/tscs454.txt b/Documentation/devicetree/bindings/sound/tscs454.txt new file mode 100644 index 000000000000..3ba3e2d2c206 --- /dev/null +++ b/Documentation/devicetree/bindings/sound/tscs454.txt @@ -0,0 +1,23 @@ +TSCS454 Audio CODEC + +Required Properties: + + - compatible : "tempo,tscs454" + + - reg : <0x69> + + - clock-names: Must one of the following "xtal", "mclk1", "mclk2" + + - clocks: phandle of the clock that provides the codec sysclk + + Note: If clock is not provided then bit clock is assumed + +Example: + +redwood: codec@69 { + #sound-dai-cells = <1>; + compatible = "tempo,tscs454"; + reg = <0x69>; + clock-names = "mclk1"; + clocks = <&audio_mclk>; +}; diff --git a/Documentation/devicetree/bindings/sound/wm8510.txt b/Documentation/devicetree/bindings/sound/wm8510.txt index fa1a32b85577..e6b6cc041f89 100644 --- a/Documentation/devicetree/bindings/sound/wm8510.txt +++ b/Documentation/devicetree/bindings/sound/wm8510.txt @@ -12,7 +12,7 @@ Required properties: Example: -codec: wm8510@1a { +wm8510: codec@1a { compatible = "wlf,wm8510"; reg = <0x1a>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8523.txt b/Documentation/devicetree/bindings/sound/wm8523.txt index 04746186b283..f3a6485f4b8a 100644 --- a/Documentation/devicetree/bindings/sound/wm8523.txt +++ b/Documentation/devicetree/bindings/sound/wm8523.txt @@ -10,7 +10,7 @@ Required properties: Example: -codec: wm8523@1a { +wm8523: codec@1a { compatible = "wlf,wm8523"; reg = <0x1a>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8524.txt b/Documentation/devicetree/bindings/sound/wm8524.txt index 0f0553563fc1..f6c0c263b135 100644 --- a/Documentation/devicetree/bindings/sound/wm8524.txt +++ b/Documentation/devicetree/bindings/sound/wm8524.txt @@ -10,7 +10,7 @@ Required properties: Example: -codec: wm8524 { +wm8524: codec { compatible = "wlf,wm8524"; wlf,mute-gpios = <&gpio1 8 GPIO_ACTIVE_LOW>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8580.txt b/Documentation/devicetree/bindings/sound/wm8580.txt index 78fce9b14954..ff3f9f5f2111 100644 --- a/Documentation/devicetree/bindings/sound/wm8580.txt +++ b/Documentation/devicetree/bindings/sound/wm8580.txt @@ -10,7 +10,7 @@ Required properties: Example: -codec: wm8580@1a { +wm8580: codec@1a { compatible = "wlf,wm8580"; reg = <0x1a>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8711.txt b/Documentation/devicetree/bindings/sound/wm8711.txt index 8ed9998cd23c..c30a1387c4bf 100644 --- a/Documentation/devicetree/bindings/sound/wm8711.txt +++ b/Documentation/devicetree/bindings/sound/wm8711.txt @@ -12,7 +12,7 @@ Required properties: Example: -codec: wm8711@1a { +wm8711: codec@1a { compatible = "wlf,wm8711"; reg = <0x1a>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8728.txt b/Documentation/devicetree/bindings/sound/wm8728.txt index a8b5c3668e60..a3608b4c78b9 100644 --- a/Documentation/devicetree/bindings/sound/wm8728.txt +++ b/Documentation/devicetree/bindings/sound/wm8728.txt @@ -12,7 +12,7 @@ Required properties: Example: -codec: wm8728@1a { +wm8728: codec@1a { compatible = "wlf,wm8728"; reg = <0x1a>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8731.txt b/Documentation/devicetree/bindings/sound/wm8731.txt index 236690e99b87..f660d9bb0e69 100644 --- a/Documentation/devicetree/bindings/sound/wm8731.txt +++ b/Documentation/devicetree/bindings/sound/wm8731.txt @@ -12,7 +12,7 @@ Required properties: Example: -codec: wm8731@1a { +wm8731: codec@1a { compatible = "wlf,wm8731"; reg = <0x1a>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8737.txt b/Documentation/devicetree/bindings/sound/wm8737.txt index 4bc2cea3b140..eda1ec6a7563 100644 --- a/Documentation/devicetree/bindings/sound/wm8737.txt +++ b/Documentation/devicetree/bindings/sound/wm8737.txt @@ -12,7 +12,7 @@ Required properties: Example: -codec: wm8737@1a { +wm8737: codec@1a { compatible = "wlf,wm8737"; reg = <0x1a>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8741.txt b/Documentation/devicetree/bindings/sound/wm8741.txt index a13315408719..b69e196c741c 100644 --- a/Documentation/devicetree/bindings/sound/wm8741.txt +++ b/Documentation/devicetree/bindings/sound/wm8741.txt @@ -21,7 +21,7 @@ Optional properties: Example: -codec: wm8741@1a { +wm8741: codec@1a { compatible = "wlf,wm8741"; reg = <0x1a>; diff --git a/Documentation/devicetree/bindings/sound/wm8750.txt b/Documentation/devicetree/bindings/sound/wm8750.txt index 8db239fd5ecd..682f221f6f38 100644 --- a/Documentation/devicetree/bindings/sound/wm8750.txt +++ b/Documentation/devicetree/bindings/sound/wm8750.txt @@ -12,7 +12,7 @@ Required properties: Example: -codec: wm8750@1a { +wm8750: codec@1a { compatible = "wlf,wm8750"; reg = <0x1a>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8753.txt b/Documentation/devicetree/bindings/sound/wm8753.txt index 8eee61282105..eca9e5a825a9 100644 --- a/Documentation/devicetree/bindings/sound/wm8753.txt +++ b/Documentation/devicetree/bindings/sound/wm8753.txt @@ -34,7 +34,7 @@ Pins on the device (for linking into audio routes): Example: -codec: wm8753@1a { +wm8753: codec@1a { compatible = "wlf,wm8753"; reg = <0x1a>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8770.txt b/Documentation/devicetree/bindings/sound/wm8770.txt index 866e00ca150b..cac762a1105d 100644 --- a/Documentation/devicetree/bindings/sound/wm8770.txt +++ b/Documentation/devicetree/bindings/sound/wm8770.txt @@ -10,7 +10,7 @@ Required properties: Example: -codec: wm8770@1 { +wm8770: codec@1 { compatible = "wlf,wm8770"; reg = <1>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8776.txt b/Documentation/devicetree/bindings/sound/wm8776.txt index 3b9ca49abc2b..01173369c3ed 100644 --- a/Documentation/devicetree/bindings/sound/wm8776.txt +++ b/Documentation/devicetree/bindings/sound/wm8776.txt @@ -12,7 +12,7 @@ Required properties: Example: -codec: wm8776@1a { +wm8776: codec@1a { compatible = "wlf,wm8776"; reg = <0x1a>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8804.txt b/Documentation/devicetree/bindings/sound/wm8804.txt index 6fd124b16496..2c1641c17a91 100644 --- a/Documentation/devicetree/bindings/sound/wm8804.txt +++ b/Documentation/devicetree/bindings/sound/wm8804.txt @@ -19,7 +19,7 @@ Optional properties: Example: -codec: wm8804@1a { +wm8804: codec@1a { compatible = "wlf,wm8804"; reg = <0x1a>; }; diff --git a/Documentation/devicetree/bindings/sound/wm8903.txt b/Documentation/devicetree/bindings/sound/wm8903.txt index afc51caf1137..6371c2434afe 100644 --- a/Documentation/devicetree/bindings/sound/wm8903.txt +++ b/Documentation/devicetree/bindings/sound/wm8903.txt @@ -57,7 +57,7 @@ Pins on the device (for linking into audio routes): Example: -codec: wm8903@1a { +wm8903: codec@1a { compatible = "wlf,wm8903"; reg = <0x1a>; interrupts = < 347 >; diff --git a/Documentation/devicetree/bindings/sound/wm8960.txt b/Documentation/devicetree/bindings/sound/wm8960.txt index 2deb8a3da9c5..6d29ac3750ee 100644 --- a/Documentation/devicetree/bindings/sound/wm8960.txt +++ b/Documentation/devicetree/bindings/sound/wm8960.txt @@ -23,7 +23,7 @@ Optional properties: Example: -codec: wm8960@1a { +wm8960: codec@1a { compatible = "wlf,wm8960"; reg = <0x1a>; diff --git a/Documentation/devicetree/bindings/sound/wm8962.txt b/Documentation/devicetree/bindings/sound/wm8962.txt index 7f82b59ec8f9..dcfa9a3369fd 100644 --- a/Documentation/devicetree/bindings/sound/wm8962.txt +++ b/Documentation/devicetree/bindings/sound/wm8962.txt @@ -24,7 +24,7 @@ Optional properties: Example: -codec: wm8962@1a { +wm8962: codec@1a { compatible = "wlf,wm8962"; reg = <0x1a>; diff --git a/Documentation/devicetree/bindings/sound/wm8994.txt b/Documentation/devicetree/bindings/sound/wm8994.txt index 68c4e8d96bed..4a9dead1b7d3 100644 --- a/Documentation/devicetree/bindings/sound/wm8994.txt +++ b/Documentation/devicetree/bindings/sound/wm8994.txt @@ -59,7 +59,7 @@ Optional properties: Example: -codec: wm8994@1a { +wm8994: codec@1a { compatible = "wlf,wm8994"; reg = <0x1a>; diff --git a/Documentation/devicetree/bindings/thermal/exynos-thermal.txt b/Documentation/devicetree/bindings/thermal/exynos-thermal.txt index 1b596fd38dc4..b957acff57aa 100644 --- a/Documentation/devicetree/bindings/thermal/exynos-thermal.txt +++ b/Documentation/devicetree/bindings/thermal/exynos-thermal.txt @@ -49,19 +49,6 @@ on the SoC (only first trip points defined in DT will be configured): - samsung,exynos5433-tmu: 8 - samsung,exynos7-tmu: 8 -Following properties are mandatory (depending on SoC): -- samsung,tmu_gain: Gain value for internal TMU operation. -- samsung,tmu_reference_voltage: Value of TMU IP block's reference voltage -- samsung,tmu_noise_cancel_mode: Mode for noise cancellation -- samsung,tmu_efuse_value: Default level of temperature - it is needed when - in factory fusing produced wrong value -- samsung,tmu_min_efuse_value: Minimum temperature fused value -- samsung,tmu_max_efuse_value: Maximum temperature fused value -- samsung,tmu_first_point_trim: First point trimming value -- samsung,tmu_second_point_trim: Second point trimming value -- samsung,tmu_default_temp_offset: Default temperature offset -- samsung,tmu_cal_type: Callibration type - ** Optional properties: - vtmu-supply: This entry is optional and provides the regulator node supplying @@ -78,7 +65,7 @@ Example 1): clocks = <&clock 383>; clock-names = "tmu_apbif"; vtmu-supply = <&tmu_regulator_node>; - #include "exynos4412-tmu-sensor-conf.dtsi" + #thermal-sensor-cells = <0>; }; Example 2): @@ -89,7 +76,7 @@ Example 2): interrupts = <0 58 0>; clocks = <&clock 21>; clock-names = "tmu_apbif"; - #include "exynos5440-tmu-sensor-conf.dtsi" + #thermal-sensor-cells = <0>; }; Example 3): (In case of Exynos5420 "with misplaced TRIMINFO register") @@ -99,7 +86,7 @@ Example 3): (In case of Exynos5420 "with misplaced TRIMINFO register") interrupts = <0 184 0>; clocks = <&clock 318>, <&clock 318>; clock-names = "tmu_apbif", "tmu_triminfo_apbif"; - #include "exynos4412-tmu-sensor-conf.dtsi" + #thermal-sensor-cells = <0>; }; tmu_cpu3: tmu@1006c000 { @@ -108,7 +95,7 @@ Example 3): (In case of Exynos5420 "with misplaced TRIMINFO register") interrupts = <0 185 0>; clocks = <&clock 318>, <&clock 319>; clock-names = "tmu_apbif", "tmu_triminfo_apbif"; - #include "exynos4412-tmu-sensor-conf.dtsi" + #thermal-sensor-cells = <0>; }; tmu_gpu: tmu@100a0000 { @@ -117,7 +104,7 @@ Example 3): (In case of Exynos5420 "with misplaced TRIMINFO register") interrupts = <0 215 0>; clocks = <&clock 319>, <&clock 318>; clock-names = "tmu_apbif", "tmu_triminfo_apbif"; - #include "exynos4412-tmu-sensor-conf.dtsi" + #thermal-sensor-cells = <0>; }; Note: For multi-instance tmu each instance should have an alias correctly diff --git a/Documentation/devicetree/bindings/thermal/thermal.txt b/Documentation/devicetree/bindings/thermal/thermal.txt index 1719d47a5e2f..cc553f0952c5 100644 --- a/Documentation/devicetree/bindings/thermal/thermal.txt +++ b/Documentation/devicetree/bindings/thermal/thermal.txt @@ -55,8 +55,7 @@ of heat dissipation). For example a fan's cooling states correspond to the different fan speeds possible. Cooling states are referred to by single unsigned integers, where larger numbers mean greater heat dissipation. The precise set of cooling states associated with a device -(as referred to by the cooling-min-level and cooling-max-level -properties) should be defined in a particular device's binding. +should be defined in a particular device's binding. For more examples of cooling devices, refer to the example sections below. Required properties: @@ -69,15 +68,6 @@ Required properties: See Cooling device maps section below for more details on how consumers refer to cooling devices. -Optional properties: -- cooling-min-level: An integer indicating the smallest - Type: unsigned cooling state accepted. Typically 0. - Size: one cell - -- cooling-max-level: An integer indicating the largest - Type: unsigned cooling state accepted. - Size: one cell - * Trip points The trip node is a node to describe a point in the temperature domain @@ -226,8 +216,6 @@ cpus { 396000 950000 198000 850000 >; - cooling-min-level = <0>; - cooling-max-level = <3>; #cooling-cells = <2>; /* min followed by max */ }; ... @@ -241,8 +229,6 @@ cpus { */ fan0: fan@48 { ... - cooling-min-level = <0>; - cooling-max-level = <9>; #cooling-cells = <2>; /* min followed by max */ }; }; diff --git a/Documentation/devicetree/bindings/timer/nuvoton,npcm7xx-timer.txt b/Documentation/devicetree/bindings/timer/nuvoton,npcm7xx-timer.txt new file mode 100644 index 000000000000..ea22dfe485be --- /dev/null +++ b/Documentation/devicetree/bindings/timer/nuvoton,npcm7xx-timer.txt @@ -0,0 +1,21 @@ +Nuvoton NPCM7xx timer + +Nuvoton NPCM7xx have three timer modules, each timer module provides five 24-bit +timer counters. + +Required properties: +- compatible : "nuvoton,npcm750-timer" for Poleg NPCM750. +- reg : Offset and length of the register set for the device. +- interrupts : Contain the timer interrupt with flags for + falling edge. +- clocks : phandle of timer reference clock (usually a 25 MHz clock). + +Example: + +timer@f0008000 { + compatible = "nuvoton,npcm750-timer"; + interrupts = <GIC_SPI 32 IRQ_TYPE_LEVEL_HIGH>; + reg = <0xf0008000 0x50>; + clocks = <&clk NPCM7XX_CLK_TIMER>; +}; + diff --git a/Documentation/devicetree/bindings/timer/nxp,tpm-timer.txt b/Documentation/devicetree/bindings/timer/nxp,tpm-timer.txt index b4aa7ddb5b13..f82087b220f4 100644 --- a/Documentation/devicetree/bindings/timer/nxp,tpm-timer.txt +++ b/Documentation/devicetree/bindings/timer/nxp,tpm-timer.txt @@ -15,7 +15,7 @@ Required properties: - interrupts : Should be the clock event device interrupt. - clocks : The clocks provided by the SoC to drive the timer, must contain an entry for each entry in clock-names. -- clock-names : Must include the following entries: "igp" and "per". +- clock-names : Must include the following entries: "ipg" and "per". Example: tpm5: tpm@40260000 { diff --git a/Documentation/devicetree/bindings/trivial-devices.txt b/Documentation/devicetree/bindings/trivial-devices.txt index 2e3740f98c41..763a2808a95c 100644 --- a/Documentation/devicetree/bindings/trivial-devices.txt +++ b/Documentation/devicetree/bindings/trivial-devices.txt @@ -75,6 +75,18 @@ maxim,max6621 PECI-to-I2C translator for PECI-to-SMBus/I2C protocol conversion maxim,max6625 9-Bit/12-Bit Temperature Sensors with I²C-Compatible Serial Interface mcube,mc3230 mCube 3-axis 8-bit digital accelerometer memsic,mxc6225 MEMSIC 2-axis 8-bit digital accelerometer +microchip,mcp4017-502 Microchip 7-bit Single I2C Digital POT (5k) +microchip,mcp4017-103 Microchip 7-bit Single I2C Digital POT (10k) +microchip,mcp4017-503 Microchip 7-bit Single I2C Digital POT (50k) +microchip,mcp4017-104 Microchip 7-bit Single I2C Digital POT (100k) +microchip,mcp4018-502 Microchip 7-bit Single I2C Digital POT (5k) +microchip,mcp4018-103 Microchip 7-bit Single I2C Digital POT (10k) +microchip,mcp4018-503 Microchip 7-bit Single I2C Digital POT (50k) +microchip,mcp4018-104 Microchip 7-bit Single I2C Digital POT (100k) +microchip,mcp4019-502 Microchip 7-bit Single I2C Digital POT (5k) +microchip,mcp4019-103 Microchip 7-bit Single I2C Digital POT (10k) +microchip,mcp4019-503 Microchip 7-bit Single I2C Digital POT (50k) +microchip,mcp4019-104 Microchip 7-bit Single I2C Digital POT (100k) microchip,mcp4531-502 Microchip 7-bit Single I2C Digital Potentiometer (5k) microchip,mcp4531-103 Microchip 7-bit Single I2C Digital Potentiometer (10k) microchip,mcp4531-503 Microchip 7-bit Single I2C Digital Potentiometer (50k) diff --git a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt index 0e03344e2e8b..2e9318151df7 100644 --- a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt +++ b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt @@ -76,6 +76,10 @@ Optional properties: needs to make sure it does not send more than 90% maximum_periodic_data_per_frame. The use case is multiple transactions, but less frame rate. +- mux-controls: The mux control for toggling host/device output of this + controller. It's expected that a mux state of 0 indicates device mode and a + mux state of 1 indicates host mode. +- mux-control-names: Shall be "usb_switch" if mux-controls is specified. i.mx specific properties - fsl,usbmisc: phandler of non-core register device, with one @@ -102,4 +106,6 @@ Example: rx-burst-size-dword = <0x10>; extcon = <0>, <&usb_id>; phy-clkgate-delay-us = <400>; + mux-controls = <&usb_switch>; + mux-control-names = "usb_switch"; }; diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt index 0dbd3083e7dd..7f13ebef06cb 100644 --- a/Documentation/devicetree/bindings/usb/dwc3.txt +++ b/Documentation/devicetree/bindings/usb/dwc3.txt @@ -7,6 +7,26 @@ Required properties: - compatible: must be "snps,dwc3" - reg : Address and length of the register set for the device - interrupts: Interrupts used by the dwc3 controller. + - clock-names: should contain "ref", "bus_early", "suspend" + - clocks: list of phandle and clock specifier pairs corresponding to + entries in the clock-names property. + +Exception for clocks: + clocks are optional if the parent node (i.e. glue-layer) is compatible to + one of the following: + "amlogic,meson-axg-dwc3" + "amlogic,meson-gxl-dwc3" + "cavium,octeon-7130-usb-uctl" + "qcom,dwc3" + "samsung,exynos5250-dwusb3" + "samsung,exynos7-dwusb3" + "sprd,sc9860-dwc3" + "st,stih407-dwc3" + "ti,am437x-dwc3" + "ti,dwc3" + "ti,keystone-dwc3" + "rockchip,rk3399-dwc3" + "xlnx,zynqmp-dwc3" Optional properties: - usb-phy : array of phandle for the PHY device. The first element @@ -15,6 +35,7 @@ Optional properties: - phys: from the *Generic PHY* bindings - phy-names: from the *Generic PHY* bindings; supported names are "usb2-phy" or "usb3-phy". + - resets: a single pair of phandle and reset specifier - snps,usb3_lpm_capable: determines if platform is USB3 LPM capable - snps,disable_scramble_quirk: true when SW should disable data scrambling. Only really useful for FPGA builds. diff --git a/Documentation/devicetree/bindings/usb/fcs,fusb302.txt b/Documentation/devicetree/bindings/usb/fcs,fusb302.txt index 472facfa5a71..6087dc7f209e 100644 --- a/Documentation/devicetree/bindings/usb/fcs,fusb302.txt +++ b/Documentation/devicetree/bindings/usb/fcs,fusb302.txt @@ -6,12 +6,6 @@ Required properties : - interrupts : Interrupt specifier Optional properties : -- fcs,max-sink-microvolt : Maximum voltage to negotiate when configured as sink -- fcs,max-sink-microamp : Maximum current to negotiate when configured as sink -- fcs,max-sink-microwatt : Maximum power to negotiate when configured as sink - If this is less then max-sink-microvolt * - max-sink-microamp then the configured current will - be clamped. - fcs,operating-sink-microwatt : Minimum amount of power accepted from a sink when negotiating diff --git a/Documentation/devicetree/bindings/usb/hisilicon,histb-xhci.txt b/Documentation/devicetree/bindings/usb/hisilicon,histb-xhci.txt new file mode 100644 index 000000000000..f4633496b122 --- /dev/null +++ b/Documentation/devicetree/bindings/usb/hisilicon,histb-xhci.txt @@ -0,0 +1,45 @@ +HiSilicon STB xHCI + +The device node for HiSilicon STB xHCI host controller + +Required properties: + - compatible: should be "hisilicon,hi3798cv200-xhci" + - reg: specifies physical base address and size of the registers + - interrupts : interrupt used by the controller + - clocks: a list of phandle + clock-specifier pairs, one for each + entry in clock-names + - clock-names: must contain + "bus": for bus clock + "utmi": for utmi clock + "pipe": for pipe clock + "suspend": for suspend clock + - resets: a list of phandle and reset specifier pairs as listed in + reset-names property. + - reset-names: must contain + "soft": for soft reset + - phys: a list of phandle + phy specifier pairs + - phy-names: must contain at least one of following: + "inno": for inno phy + "combo": for combo phy + +Optional properties: + - usb2-lpm-disable: indicate if we don't want to enable USB2 HW LPM + - usb3-lpm-capable: determines if platform is USB3 LPM capable + - imod-interval-ns: default interrupt moderation interval is 40000ns + +Example: + +xhci0: xchi@f98a0000 { + compatible = "hisilicon,hi3798cv200-xhci"; + reg = <0xf98a0000 0x10000>; + interrupts = <GIC_SPI 69 IRQ_TYPE_LEVEL_HIGH>; + clocks = <&crg HISTB_USB3_BUS_CLK>, + <&crg HISTB_USB3_UTMI_CLK>, + <&crg HISTB_USB3_PIPE_CLK>, + <&crg HISTB_USB3_SUSPEND_CLK>; + clock-names = "bus", "utmi", "pipe", "suspend"; + resets = <&crg 0xb0 12>; + reset-names = "soft"; + phys = <&usb2_phy1_port1 0>, <&combphy0 PHY_TYPE_USB3>; + phy-names = "inno", "combo"; +}; diff --git a/Documentation/devicetree/bindings/usb/qcom,dwc3.txt b/Documentation/devicetree/bindings/usb/qcom,dwc3.txt index bc8a2fa5d2bf..95afdcf3c337 100644 --- a/Documentation/devicetree/bindings/usb/qcom,dwc3.txt +++ b/Documentation/devicetree/bindings/usb/qcom,dwc3.txt @@ -1,54 +1,95 @@ Qualcomm SuperSpeed DWC3 USB SoC controller Required properties: -- compatible: should contain "qcom,dwc3" +- compatible: Compatible list, contains + "qcom,dwc3" + "qcom,msm8996-dwc3" for msm8996 SOC. + "qcom,sdm845-dwc3" for sdm845 SOC. +- reg: Offset and length of register set for QSCRATCH wrapper +- power-domains: specifies a phandle to PM domain provider node - clocks: A list of phandle + clock-specifier pairs for the clocks listed in clock-names -- clock-names: Should contain the following: +- clock-names: Should contain the following: "core" Master/Core clock, have to be >= 125 MHz for SS operation and >= 60MHz for HS operation + "mock_utmi" Mock utmi clock needed for ITP/SOF generation in + host mode. Its frequency should be 19.2MHz. + "sleep" Sleep clock, used for wakeup when USB3 core goes + into low power mode (U3). Optional clocks: - "iface" System bus AXI clock. Not present on all platforms - "sleep" Sleep clock, used when USB3 core goes into low - power mode (U3). + "iface" System bus AXI clock. + Not present on "qcom,msm8996-dwc3" compatible. + "cfg_noc" System Config NOC clock. + Not present on "qcom,msm8996-dwc3" compatible. +- assigned-clocks: Should be: + MOCK_UTMI_CLK + MASTER_CLK +- assigned-clock-rates: Should be: + 19.2Mhz (192000000) for MOCK_UTMI_CLK + >=125Mhz (125000000) for MASTER_CLK in SS mode + >=60Mhz (60000000) for MASTER_CLK in HS mode + +Optional properties: +- resets: Phandle to reset control that resets core and wrapper. +- interrupts: specifies interrupts from controller wrapper used + to wakeup from low power/susepnd state. Must contain + one or more entry for interrupt-names property +- interrupt-names: Must include the following entries: + - "hs_phy_irq": The interrupt that is asserted when a + wakeup event is received on USB2 bus + - "ss_phy_irq": The interrupt that is asserted when a + wakeup event is received on USB3 bus + - "dm_hs_phy_irq" and "dp_hs_phy_irq": Separate + interrupts for any wakeup event on DM and DP lines +- qcom,select-utmi-as-pipe-clk: if present, disable USB3 pipe_clk requirement. + Used when dwc3 operates without SSPHY and only + HS/FS/LS modes are supported. Required child node: A child node must exist to represent the core DWC3 IP block. The name of the node is not important. The content of the node is defined in dwc3.txt. Phy documentation is provided in the following places: -Documentation/devicetree/bindings/phy/qcom-dwc3-usb-phy.txt +Documentation/devicetree/bindings/phy/qcom-qmp-phy.txt - USB3 QMP PHY +Documentation/devicetree/bindings/phy/qcom-qusb2-phy.txt - USB2 QUSB2 PHY Example device nodes: hs_phy: phy@100f8800 { - compatible = "qcom,dwc3-hs-usb-phy"; - reg = <0x100f8800 0x30>; - clocks = <&gcc USB30_0_UTMI_CLK>; - clock-names = "ref"; - #phy-cells = <0>; - + compatible = "qcom,qusb2-v2-phy"; + ... }; ss_phy: phy@100f8830 { - compatible = "qcom,dwc3-ss-usb-phy"; - reg = <0x100f8830 0x30>; - clocks = <&gcc USB30_0_MASTER_CLK>; - clock-names = "ref"; - #phy-cells = <0>; - + compatible = "qcom,qmp-v3-usb3-phy"; + ... }; - usb3_0: usb30@0 { + usb3_0: usb30@a6f8800 { compatible = "qcom,dwc3"; + reg = <0xa6f8800 0x400>; #address-cells = <1>; #size-cells = <1>; - clocks = <&gcc USB30_0_MASTER_CLK>; - clock-names = "core"; - ranges; + interrupts = <0 131 0>, <0 486 0>, <0 488 0>, <0 489 0>; + interrupt-names = "hs_phy_irq", "ss_phy_irq", + "dm_hs_phy_irq", "dp_hs_phy_irq"; + + clocks = <&gcc GCC_USB30_PRIM_MASTER_CLK>, + <&gcc GCC_USB30_PRIM_MOCK_UTMI_CLK>, + <&gcc GCC_USB30_PRIM_SLEEP_CLK>; + clock-names = "core", "mock_utmi", "sleep"; + + assigned-clocks = <&gcc GCC_USB30_PRIM_MOCK_UTMI_CLK>, + <&gcc GCC_USB30_PRIM_MASTER_CLK>; + assigned-clock-rates = <19200000>, <133000000>; + + resets = <&gcc GCC_USB30_PRIM_BCR>; + reset-names = "core_reset"; + power-domains = <&gcc USB30_PRIM_GDSC>; + qcom,select-utmi-as-pipe-clk; dwc3@10000000 { compatible = "snps,dwc3"; diff --git a/Documentation/devicetree/bindings/usb/richtek,rt1711h.txt b/Documentation/devicetree/bindings/usb/richtek,rt1711h.txt new file mode 100644 index 000000000000..09e847e92e5e --- /dev/null +++ b/Documentation/devicetree/bindings/usb/richtek,rt1711h.txt @@ -0,0 +1,17 @@ +Richtek RT1711H TypeC PD Controller. + +Required properties: + - compatible : Must be "richtek,rt1711h". + - reg : Must be 0x4e, it's slave address of RT1711H. + - interrupt-parent : the phandle for the interrupt controller that + provides interrupts for this device. + - interrupts : <a b> where a is the interrupt number and b represents an + encoding of the sense and level information for the interrupt. + +Example : +rt1711h@4e { + compatible = "richtek,rt1711h"; + reg = <0x4e>; + interrupt-parent = <&gpio26>; + interrupts = <0 IRQ_TYPE_LEVEL_LOW>; +}; diff --git a/Documentation/devicetree/bindings/usb/usb-xhci.txt b/Documentation/devicetree/bindings/usb/usb-xhci.txt index c4c00dff4b56..bd1dd316fb23 100644 --- a/Documentation/devicetree/bindings/usb/usb-xhci.txt +++ b/Documentation/devicetree/bindings/usb/usb-xhci.txt @@ -28,7 +28,10 @@ Required properties: - interrupts: one XHCI interrupt should be described here. Optional properties: - - clocks: reference to a clock + - clocks: reference to the clocks + - clock-names: mandatory if there is a second clock, in this case + the name must be "core" for the first clock and "reg" for the + second one - usb2-lpm-disable: indicate if we don't want to enable USB2 HW LPM - usb3-lpm-capable: determines if platform is USB3 LPM capable - quirk-broken-port-ped: set if the controller has broken port disable mechanism diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt index 12e8b3e576b0..36003832c2a8 100644 --- a/Documentation/devicetree/bindings/vendor-prefixes.txt +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt @@ -75,6 +75,7 @@ cnxt Conexant Systems, Inc. compulab CompuLab Ltd. cortina Cortina Systems, Inc. cosmic Cosmic Circuits +crane Crane Connectivity Solutions creative Creative Technology Ltd crystalfontz Crystalfontz America, Inc. cubietech Cubietech, Ltd. @@ -182,6 +183,7 @@ karo Ka-Ro electronics GmbH keithkoep Keith & Koep GmbH keymile Keymile GmbH khadas Khadas +kiebackpeter Kieback & Peter GmbH kinetic Kinetic Technologies kingnovel Kingnovel Technology Co., Ltd. kosagi Sutajio Ko-Usagi PTE Ltd. @@ -225,6 +227,7 @@ motorola Motorola, Inc. moxa Moxa Inc. mpl MPL AG mqmaker mqmaker Inc. +mscc Microsemi Corporation msi Micro-Star International Co. Ltd. mti Imagination Technologies Ltd. (formerly MIPS Technologies Inc.) multi-inno Multi-Inno Technology Co.,Ltd diff --git a/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.txt b/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.txt index 107280ef0025..adc6b76fcb3a 100644 --- a/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.txt +++ b/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.txt @@ -11,6 +11,7 @@ Optional properties: detail please see: Documentation/devicetree/bindings/regmap/regmap.txt. - fsl,ext-reset-output: If present the watchdog device is configured to assert its external reset (WDOG_B) instead of issuing a software reset. +- timeout-sec : Contains the watchdog timeout in seconds Examples: @@ -19,4 +20,5 @@ wdt@73f98000 { reg = <0x73f98000 0x4000>; interrupts = <58>; big-endian; + timeout-sec = <20>; }; diff --git a/Documentation/devicetree/bindings/watchdog/meson-wdt.txt b/Documentation/devicetree/bindings/watchdog/meson-wdt.txt index 8a6d84cb36c9..7588cc3971bf 100644 --- a/Documentation/devicetree/bindings/watchdog/meson-wdt.txt +++ b/Documentation/devicetree/bindings/watchdog/meson-wdt.txt @@ -9,9 +9,13 @@ Required properties: "amlogic,meson8m2-wdt" and "amlogic,meson8b-wdt" on Meson8m2 SoCs - reg : Specifies base physical address and size of the registers. +Optional properties: +- timeout-sec: contains the watchdog timeout in seconds. + Example: wdt: watchdog@c1109900 { compatible = "amlogic,meson6-wdt"; reg = <0xc1109900 0x8>; + timeout-sec = <10>; }; diff --git a/Documentation/devicetree/bindings/watchdog/mtk-wdt.txt b/Documentation/devicetree/bindings/watchdog/mtk-wdt.txt index 5b38a30e608c..859dee167b91 100644 --- a/Documentation/devicetree/bindings/watchdog/mtk-wdt.txt +++ b/Documentation/devicetree/bindings/watchdog/mtk-wdt.txt @@ -11,9 +11,13 @@ Required properties: - reg : Specifies base physical address and size of the registers. +Optional properties: +- timeout-sec: contains the watchdog timeout in seconds. + Example: wdt: watchdog@10000000 { compatible = "mediatek,mt6589-wdt"; reg = <0x10000000 0x18>; + timeout-sec = <10>; }; diff --git a/Documentation/devicetree/bindings/watchdog/nuvoton,npcm-wdt.txt b/Documentation/devicetree/bindings/watchdog/nuvoton,npcm-wdt.txt new file mode 100644 index 000000000000..6d593003c933 --- /dev/null +++ b/Documentation/devicetree/bindings/watchdog/nuvoton,npcm-wdt.txt @@ -0,0 +1,28 @@ +Nuvoton NPCM Watchdog + +Nuvoton NPCM timer module provides five 24-bit timer counters, and a watchdog. +The watchdog supports a pre-timeout interrupt that fires 10ms before the +expiry. + +Required properties: +- compatible : "nuvoton,npcm750-wdt" for NPCM750 (Poleg). +- reg : Offset and length of the register set for the device. +- interrupts : Contain the timer interrupt with flags for + falling edge. + +Required clocking property, have to be one of: +- clocks : phandle of timer reference clock. +- clock-frequency : The frequency in Hz of the clock that drives the NPCM7xx + timer (usually 25000000). + +Optional properties: +- timeout-sec : Contains the watchdog timeout in seconds + +Example: + +timer@f000801c { + compatible = "nuvoton,npcm750-wdt"; + interrupts = <GIC_SPI 47 IRQ_TYPE_LEVEL_HIGH>; + reg = <0xf000801c 0x4>; + clocks = <&clk NPCM7XX_CLK_TIMER>; +}; diff --git a/Documentation/devicetree/bindings/watchdog/sirfsoc_wdt.txt b/Documentation/devicetree/bindings/watchdog/sirfsoc_wdt.txt index 9cbc76c89b2b..0dce5e3100b4 100644 --- a/Documentation/devicetree/bindings/watchdog/sirfsoc_wdt.txt +++ b/Documentation/devicetree/bindings/watchdog/sirfsoc_wdt.txt @@ -5,10 +5,14 @@ Required properties: - reg: Address range of tick timer/WDT register set - interrupts: interrupt number to the cpu +Optional properties: +- timeout-sec : Contains the watchdog timeout in seconds + Example: timer@b0020000 { compatible = "sirf,prima2-tick"; reg = <0xb0020000 0x1000>; interrupts = <0>; + timeout-sec = <30>; }; diff --git a/Documentation/devicetree/bindings/watchdog/sunxi-wdt.txt b/Documentation/devicetree/bindings/watchdog/sunxi-wdt.txt index 62dd5baad70e..ed11ce0ac836 100644 --- a/Documentation/devicetree/bindings/watchdog/sunxi-wdt.txt +++ b/Documentation/devicetree/bindings/watchdog/sunxi-wdt.txt @@ -2,13 +2,19 @@ Allwinner SoCs Watchdog timer Required properties: -- compatible : should be either "allwinner,sun4i-a10-wdt" or - "allwinner,sun6i-a31-wdt" +- compatible : should be one of + "allwinner,sun4i-a10-wdt" + "allwinner,sun6i-a31-wdt" + "allwinner,sun50i-a64-wdt","allwinner,sun6i-a31-wdt" - reg : Specifies base physical address and size of the registers. +Optional properties: +- timeout-sec : Contains the watchdog timeout in seconds + Example: wdt: watchdog@1c20c90 { compatible = "allwinner,sun4i-a10-wdt"; reg = <0x01c20c90 0x10>; + timeout-sec = <10>; }; diff --git a/Documentation/devicetree/overlay-notes.txt b/Documentation/devicetree/overlay-notes.txt index 5175a24d387e..725fb8d255c1 100644 --- a/Documentation/devicetree/overlay-notes.txt +++ b/Documentation/devicetree/overlay-notes.txt @@ -91,13 +91,21 @@ The API is quite easy to use. return value is an error or a cookie identifying this overlay. 2. Call of_overlay_remove() to remove and cleanup the overlay changeset -previously created via the call to of_overlay_apply(). Removal of an overlay -changeset that is stacked by another will not be permitted. +previously created via the call to of_overlay_fdt_apply(). Removal of an +overlay changeset that is stacked by another will not be permitted. Finally, if you need to remove all overlays in one-go, just call of_overlay_remove_all() which will remove every single one in the correct order. +In addition, there is the option to register notifiers that get called on +overlay operations. See of_overlay_notifier_register/unregister and +enum of_overlay_notify_action for details. + +Note that a notifier callback is not supposed to store pointers to a device +tree node or its content beyond OF_OVERLAY_POST_REMOVE corresponding to the +respective node it received. + Overlay DTS Format ------------------ diff --git a/Documentation/doc-guide/parse-headers.rst b/Documentation/doc-guide/parse-headers.rst index 96a0423d5dba..82a3e43b6864 100644 --- a/Documentation/doc-guide/parse-headers.rst +++ b/Documentation/doc-guide/parse-headers.rst @@ -177,14 +177,14 @@ BUGS **** -Report bugs to Mauro Carvalho Chehab <mchehab@s-opensource.com> +Report bugs to Mauro Carvalho Chehab <mchehab@kernel.org> COPYRIGHT ********* -Copyright (c) 2016 by Mauro Carvalho Chehab <mchehab@s-opensource.com>. +Copyright (c) 2016 by Mauro Carvalho Chehab <mchehab+samsung@kernel.org>. License GPLv2: GNU GPL version 2 <http://gnu.org/licenses/gpl.html>. diff --git a/Documentation/clk.txt b/Documentation/driver-api/clk.rst index be909ed45970..511628bb3d3a 100644 --- a/Documentation/clk.txt +++ b/Documentation/driver-api/clk.rst @@ -268,9 +268,19 @@ The common clock framework uses two global locks, the prepare lock and the enable lock. The enable lock is a spinlock and is held across calls to the .enable, -.disable and .is_enabled operations. Those operations are thus not allowed to -sleep, and calls to the clk_enable(), clk_disable() and clk_is_enabled() API -functions are allowed in atomic context. +.disable operations. Those operations are thus not allowed to sleep, +and calls to the clk_enable(), clk_disable() API functions are allowed in +atomic context. + +For clk_is_enabled() API, it is also designed to be allowed to be used in +atomic context. However, it doesn't really make any sense to hold the enable +lock in core, unless you want to do something else with the information of +the enable state with that lock held. Otherwise, seeing if a clk is enabled is +a one-shot read of the enabled state, which could just as easily change after +the function returns because the lock is released. Thus the user of this API +needs to handle synchronizing the read of the state with whatever they're +using it for to make sure that the enable state doesn't change during that +time. The prepare lock is a mutex and is held across calls to all other operations. All those operations are allowed to sleep, and calls to the corresponding API diff --git a/Documentation/driver-api/device_connection.rst b/Documentation/driver-api/device_connection.rst index affbc5566ab0..ba364224c349 100644 --- a/Documentation/driver-api/device_connection.rst +++ b/Documentation/driver-api/device_connection.rst @@ -40,4 +40,4 @@ API --- .. kernel-doc:: drivers/base/devcon.c - : functions: device_connection_find_match device_connection_find device_connection_add device_connection_remove + :functions: device_connection_find_match device_connection_find device_connection_add device_connection_remove diff --git a/Documentation/driver-api/firmware/fallback-mechanisms.rst b/Documentation/driver-api/firmware/fallback-mechanisms.rst index f353783ae0be..d35fed65eae9 100644 --- a/Documentation/driver-api/firmware/fallback-mechanisms.rst +++ b/Documentation/driver-api/firmware/fallback-mechanisms.rst @@ -72,9 +72,12 @@ the firmware requested, and establishes it in the device hierarchy by associating the device used to make the request as the device's parent. The sysfs directory's file attributes are defined and controlled through the new device's class (firmware_class) and group (fw_dev_attr_groups). -This is actually where the original firmware_class.c file name comes from, -as originally the only firmware loading mechanism available was the -mechanism we now use as a fallback mechanism. +This is actually where the original firmware_class module name came from, +given that originally the only firmware loading mechanism available was the +mechanism we now use as a fallback mechanism, which registers a struct class +firmware_class. Because the attributes exposed are part of the module name, the +module name firmware_class cannot be renamed in the future, to ensure backward +compatibility with old userspace. To load firmware using the sysfs interface we expose a loading indicator, and a file upload firmware into: @@ -83,7 +86,7 @@ and a file upload firmware into: * /sys/$DEVPATH/data To upload firmware you will echo 1 onto the loading file to indicate -you are loading firmware. You then cat the firmware into the data file, +you are loading firmware. You then write the firmware into the data file, and you notify the kernel the firmware is ready by echo'ing 0 onto the loading file. @@ -136,7 +139,8 @@ by kobject uevents. This is specially exacerbated due to the fact that most distributions today disable CONFIG_FW_LOADER_USER_HELPER_FALLBACK. Refer to do_firmware_uevent() for details of the kobject event variables -setup. Variables passwdd with a kobject add event: +setup. The variables currently passed to userspace with a "kobject add" +event are: * FIRMWARE=firmware name * TIMEOUT=timeout value diff --git a/Documentation/driver-api/firmware/firmware_cache.rst b/Documentation/driver-api/firmware/firmware_cache.rst index 2210e5bfb332..c2e69d9c6bf1 100644 --- a/Documentation/driver-api/firmware/firmware_cache.rst +++ b/Documentation/driver-api/firmware/firmware_cache.rst @@ -29,8 +29,8 @@ Some implementation details about the firmware cache setup: * If an asynchronous call is used the firmware cache is only set up for a device if if the second argument (uevent) to request_firmware_nowait() is true. When uevent is true it requests that a kobject uevent be sent to - userspace for the firmware request. For details refer to the Fackback - mechanism documented below. + userspace for the firmware request through the sysfs fallback mechanism + if the firmware file is not found. * If the firmware cache is determined to be needed as per the above two criteria the firmware cache is setup by adding a devres entry for the diff --git a/Documentation/driver-api/firmware/request_firmware.rst b/Documentation/driver-api/firmware/request_firmware.rst index cf4516dfbf96..f62bdcbfed5b 100644 --- a/Documentation/driver-api/firmware/request_firmware.rst +++ b/Documentation/driver-api/firmware/request_firmware.rst @@ -17,17 +17,22 @@ an error is returned. request_firmware ---------------- -.. kernel-doc:: drivers/base/firmware_class.c +.. kernel-doc:: drivers/base/firmware_loader/main.c :functions: request_firmware +firmware_request_nowarn +----------------------- +.. kernel-doc:: drivers/base/firmware_loader/main.c + :functions: firmware_request_nowarn + request_firmware_direct ----------------------- -.. kernel-doc:: drivers/base/firmware_class.c +.. kernel-doc:: drivers/base/firmware_loader/main.c :functions: request_firmware_direct request_firmware_into_buf ------------------------- -.. kernel-doc:: drivers/base/firmware_class.c +.. kernel-doc:: drivers/base/firmware_loader/main.c :functions: request_firmware_into_buf Asynchronous firmware requests @@ -41,7 +46,7 @@ in atomic contexts. request_firmware_nowait ----------------------- -.. kernel-doc:: drivers/base/firmware_class.c +.. kernel-doc:: drivers/base/firmware_loader/main.c :functions: request_firmware_nowait Special optimizations on reboot @@ -50,12 +55,12 @@ Special optimizations on reboot Some devices have an optimization in place to enable the firmware to be retained during system reboot. When such optimizations are used the driver author must ensure the firmware is still available on resume from suspend, -this can be done with firmware_request_cache() insted of requesting for the -firmare to be loaded. +this can be done with firmware_request_cache() instead of requesting for the +firmware to be loaded. firmware_request_cache() ------------------------ -.. kernel-doc:: drivers/base/firmware_class.c +------------------------ +.. kernel-doc:: drivers/base/firmware_loader/main.c :functions: firmware_request_cache request firmware API expected driver use diff --git a/Documentation/driver-api/fpga/fpga-bridge.rst b/Documentation/driver-api/fpga/fpga-bridge.rst new file mode 100644 index 000000000000..2c2aaca894bf --- /dev/null +++ b/Documentation/driver-api/fpga/fpga-bridge.rst @@ -0,0 +1,49 @@ +FPGA Bridge +=========== + +API to implement a new FPGA bridge +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +.. kernel-doc:: include/linux/fpga/fpga-bridge.h + :functions: fpga_bridge + +.. kernel-doc:: include/linux/fpga/fpga-bridge.h + :functions: fpga_bridge_ops + +.. kernel-doc:: drivers/fpga/fpga-bridge.c + :functions: fpga_bridge_create + +.. kernel-doc:: drivers/fpga/fpga-bridge.c + :functions: fpga_bridge_free + +.. kernel-doc:: drivers/fpga/fpga-bridge.c + :functions: fpga_bridge_register + +.. kernel-doc:: drivers/fpga/fpga-bridge.c + :functions: fpga_bridge_unregister + +API to control an FPGA bridge +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +You probably won't need these directly. FPGA regions should handle this. + +.. kernel-doc:: drivers/fpga/fpga-bridge.c + :functions: of_fpga_bridge_get + +.. kernel-doc:: drivers/fpga/fpga-bridge.c + :functions: fpga_bridge_get + +.. kernel-doc:: drivers/fpga/fpga-bridge.c + :functions: fpga_bridge_put + +.. kernel-doc:: drivers/fpga/fpga-bridge.c + :functions: fpga_bridge_get_to_list + +.. kernel-doc:: drivers/fpga/fpga-bridge.c + :functions: of_fpga_bridge_get_to_list + +.. kernel-doc:: drivers/fpga/fpga-bridge.c + :functions: fpga_bridge_enable + +.. kernel-doc:: drivers/fpga/fpga-bridge.c + :functions: fpga_bridge_disable diff --git a/Documentation/driver-api/fpga/fpga-mgr.rst b/Documentation/driver-api/fpga/fpga-mgr.rst new file mode 100644 index 000000000000..bcf2dd24e179 --- /dev/null +++ b/Documentation/driver-api/fpga/fpga-mgr.rst @@ -0,0 +1,220 @@ +FPGA Manager +============ + +Overview +-------- + +The FPGA manager core exports a set of functions for programming an FPGA with +an image. The API is manufacturer agnostic. All manufacturer specifics are +hidden away in a low level driver which registers a set of ops with the core. +The FPGA image data itself is very manufacturer specific, but for our purposes +it's just binary data. The FPGA manager core won't parse it. + +The FPGA image to be programmed can be in a scatter gather list, a single +contiguous buffer, or a firmware file. Because allocating contiguous kernel +memory for the buffer should be avoided, users are encouraged to use a scatter +gather list instead if possible. + +The particulars for programming the image are presented in a structure (struct +fpga_image_info). This struct contains parameters such as pointers to the +FPGA image as well as image-specific particulars such as whether the image was +built for full or partial reconfiguration. + +How to support a new FPGA device +-------------------------------- + +To add another FPGA manager, write a driver that implements a set of ops. The +probe function calls fpga_mgr_register(), such as:: + + static const struct fpga_manager_ops socfpga_fpga_ops = { + .write_init = socfpga_fpga_ops_configure_init, + .write = socfpga_fpga_ops_configure_write, + .write_complete = socfpga_fpga_ops_configure_complete, + .state = socfpga_fpga_ops_state, + }; + + static int socfpga_fpga_probe(struct platform_device *pdev) + { + struct device *dev = &pdev->dev; + struct socfpga_fpga_priv *priv; + struct fpga_manager *mgr; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + /* + * do ioremaps, get interrupts, etc. and save + * them in priv + */ + + mgr = fpga_mgr_create(dev, "Altera SOCFPGA FPGA Manager", + &socfpga_fpga_ops, priv); + if (!mgr) + return -ENOMEM; + + platform_set_drvdata(pdev, mgr); + + ret = fpga_mgr_register(mgr); + if (ret) + fpga_mgr_free(mgr); + + return ret; + } + + static int socfpga_fpga_remove(struct platform_device *pdev) + { + struct fpga_manager *mgr = platform_get_drvdata(pdev); + + fpga_mgr_unregister(mgr); + + return 0; + } + + +The ops will implement whatever device specific register writes are needed to +do the programming sequence for this particular FPGA. These ops return 0 for +success or negative error codes otherwise. + +The programming sequence is:: + 1. .write_init + 2. .write or .write_sg (may be called once or multiple times) + 3. .write_complete + +The .write_init function will prepare the FPGA to receive the image data. The +buffer passed into .write_init will be atmost .initial_header_size bytes long, +if the whole bitstream is not immediately available then the core code will +buffer up at least this much before starting. + +The .write function writes a buffer to the FPGA. The buffer may be contain the +whole FPGA image or may be a smaller chunk of an FPGA image. In the latter +case, this function is called multiple times for successive chunks. This interface +is suitable for drivers which use PIO. + +The .write_sg version behaves the same as .write except the input is a sg_table +scatter list. This interface is suitable for drivers which use DMA. + +The .write_complete function is called after all the image has been written +to put the FPGA into operating mode. + +The ops include a .state function which will read the hardware FPGA manager and +return a code of type enum fpga_mgr_states. It doesn't result in a change in +hardware state. + +How to write an image buffer to a supported FPGA +------------------------------------------------ + +Some sample code:: + + #include <linux/fpga/fpga-mgr.h> + + struct fpga_manager *mgr; + struct fpga_image_info *info; + int ret; + + /* + * Get a reference to FPGA manager. The manager is not locked, so you can + * hold onto this reference without it preventing programming. + * + * This example uses the device node of the manager. Alternatively, use + * fpga_mgr_get(dev) instead if you have the device. + */ + mgr = of_fpga_mgr_get(mgr_node); + + /* struct with information about the FPGA image to program. */ + info = fpga_image_info_alloc(dev); + + /* flags indicates whether to do full or partial reconfiguration */ + info->flags = FPGA_MGR_PARTIAL_RECONFIG; + + /* + * At this point, indicate where the image is. This is pseudo-code; you're + * going to use one of these three. + */ + if (image is in a scatter gather table) { + + info->sgt = [your scatter gather table] + + } else if (image is in a buffer) { + + info->buf = [your image buffer] + info->count = [image buffer size] + + } else if (image is in a firmware file) { + + info->firmware_name = devm_kstrdup(dev, firmware_name, GFP_KERNEL); + + } + + /* Get exclusive control of FPGA manager */ + ret = fpga_mgr_lock(mgr); + + /* Load the buffer to the FPGA */ + ret = fpga_mgr_buf_load(mgr, &info, buf, count); + + /* Release the FPGA manager */ + fpga_mgr_unlock(mgr); + fpga_mgr_put(mgr); + + /* Deallocate the image info if you're done with it */ + fpga_image_info_free(info); + +API for implementing a new FPGA Manager driver +---------------------------------------------- + +.. kernel-doc:: include/linux/fpga/fpga-mgr.h + :functions: fpga_manager + +.. kernel-doc:: include/linux/fpga/fpga-mgr.h + :functions: fpga_manager_ops + +.. kernel-doc:: drivers/fpga/fpga-mgr.c + :functions: fpga_mgr_create + +.. kernel-doc:: drivers/fpga/fpga-mgr.c + :functions: fpga_mgr_free + +.. kernel-doc:: drivers/fpga/fpga-mgr.c + :functions: fpga_mgr_register + +.. kernel-doc:: drivers/fpga/fpga-mgr.c + :functions: fpga_mgr_unregister + +API for programming a FPGA +-------------------------- + +.. kernel-doc:: include/linux/fpga/fpga-mgr.h + :functions: fpga_image_info + +.. kernel-doc:: include/linux/fpga/fpga-mgr.h + :functions: fpga_mgr_states + +.. kernel-doc:: drivers/fpga/fpga-mgr.c + :functions: fpga_image_info_alloc + +.. kernel-doc:: drivers/fpga/fpga-mgr.c + :functions: fpga_image_info_free + +.. kernel-doc:: drivers/fpga/fpga-mgr.c + :functions: of_fpga_mgr_get + +.. kernel-doc:: drivers/fpga/fpga-mgr.c + :functions: fpga_mgr_get + +.. kernel-doc:: drivers/fpga/fpga-mgr.c + :functions: fpga_mgr_put + +.. kernel-doc:: drivers/fpga/fpga-mgr.c + :functions: fpga_mgr_lock + +.. kernel-doc:: drivers/fpga/fpga-mgr.c + :functions: fpga_mgr_unlock + +.. kernel-doc:: include/linux/fpga/fpga-mgr.h + :functions: fpga_mgr_states + +Note - use :c:func:`fpga_region_program_fpga()` instead of :c:func:`fpga_mgr_load()` + +.. kernel-doc:: drivers/fpga/fpga-mgr.c + :functions: fpga_mgr_load diff --git a/Documentation/driver-api/fpga/fpga-region.rst b/Documentation/driver-api/fpga/fpga-region.rst new file mode 100644 index 000000000000..f89e4a311722 --- /dev/null +++ b/Documentation/driver-api/fpga/fpga-region.rst @@ -0,0 +1,102 @@ +FPGA Region +=========== + +Overview +-------- + +This document is meant to be an brief overview of the FPGA region API usage. A +more conceptual look at regions can be found in the Device Tree binding +document [#f1]_. + +For the purposes of this API document, let's just say that a region associates +an FPGA Manager and a bridge (or bridges) with a reprogrammable region of an +FPGA or the whole FPGA. The API provides a way to register a region and to +program a region. + +Currently the only layer above fpga-region.c in the kernel is the Device Tree +support (of-fpga-region.c) described in [#f1]_. The DT support layer uses regions +to program the FPGA and then DT to handle enumeration. The common region code +is intended to be used by other schemes that have other ways of accomplishing +enumeration after programming. + +An fpga-region can be set up to know the following things: + + * which FPGA manager to use to do the programming + + * which bridges to disable before programming and enable afterwards. + +Additional info needed to program the FPGA image is passed in the struct +fpga_image_info including: + + * pointers to the image as either a scatter-gather buffer, a contiguous + buffer, or the name of firmware file + + * flags indicating specifics such as whether the image if for partial + reconfiguration. + +How to program a FPGA using a region +------------------------------------ + +First, allocate the info struct:: + + info = fpga_image_info_alloc(dev); + if (!info) + return -ENOMEM; + +Set flags as needed, i.e.:: + + info->flags |= FPGA_MGR_PARTIAL_RECONFIG; + +Point to your FPGA image, such as:: + + info->sgt = &sgt; + +Add info to region and do the programming:: + + region->info = info; + ret = fpga_region_program_fpga(region); + +:c:func:`fpga_region_program_fpga()` operates on info passed in the +fpga_image_info (region->info). This function will attempt to: + + * lock the region's mutex + * lock the region's FPGA manager + * build a list of FPGA bridges if a method has been specified to do so + * disable the bridges + * program the FPGA + * re-enable the bridges + * release the locks + +Then you will want to enumerate whatever hardware has appeared in the FPGA. + +How to add a new FPGA region +---------------------------- + +An example of usage can be seen in the probe function of [#f2]_. + +.. [#f1] ../devicetree/bindings/fpga/fpga-region.txt +.. [#f2] ../../drivers/fpga/of-fpga-region.c + +API to program a FGPA +--------------------- + +.. kernel-doc:: drivers/fpga/fpga-region.c + :functions: fpga_region_program_fpga + +API to add a new FPGA region +---------------------------- + +.. kernel-doc:: include/linux/fpga/fpga-region.h + :functions: fpga_region + +.. kernel-doc:: drivers/fpga/fpga-region.c + :functions: fpga_region_create + +.. kernel-doc:: drivers/fpga/fpga-region.c + :functions: fpga_region_free + +.. kernel-doc:: drivers/fpga/fpga-region.c + :functions: fpga_region_register + +.. kernel-doc:: drivers/fpga/fpga-region.c + :functions: fpga_region_unregister diff --git a/Documentation/driver-api/fpga/index.rst b/Documentation/driver-api/fpga/index.rst new file mode 100644 index 000000000000..c51e5ebd544a --- /dev/null +++ b/Documentation/driver-api/fpga/index.rst @@ -0,0 +1,13 @@ +============== +FPGA Subsystem +============== + +:Author: Alan Tull + +.. toctree:: + :maxdepth: 2 + + intro + fpga-mgr + fpga-bridge + fpga-region diff --git a/Documentation/driver-api/fpga/intro.rst b/Documentation/driver-api/fpga/intro.rst new file mode 100644 index 000000000000..51cd81dbb4dc --- /dev/null +++ b/Documentation/driver-api/fpga/intro.rst @@ -0,0 +1,54 @@ +Introduction +============ + +The FPGA subsystem supports reprogramming FPGAs dynamically under +Linux. Some of the core intentions of the FPGA subsystems are: + +* The FPGA subsystem is vendor agnostic. + +* The FPGA subsystem separates upper layers (userspace interfaces and + enumeration) from lower layers that know how to program a specific + FPGA. + +* Code should not be shared between upper and lower layers. This + should go without saying. If that seems necessary, there's probably + framework functionality that that can be added that will benefit + other users. Write the linux-fpga mailing list and maintainers and + seek out a solution that expands the framework for broad reuse. + +* Generally, when adding code, think of the future. Plan for re-use. + +The framework in the kernel is divided into: + +FPGA Manager +------------ + +If you are adding a new FPGA or a new method of programming a FPGA, +this is the subsystem for you. Low level FPGA manager drivers contain +the knowledge of how to program a specific device. This subsystem +includes the framework in fpga-mgr.c and the low level drivers that +are registered with it. + +FPGA Bridge +----------- + +FPGA Bridges prevent spurious signals from going out of a FPGA or a +region of a FPGA during programming. They are disabled before +programming begins and re-enabled afterwards. An FPGA bridge may be +actual hard hardware that gates a bus to a cpu or a soft ("freeze") +bridge in FPGA fabric that surrounds a partial reconfiguration region +of an FPGA. This subsystem includes fpga-bridge.c and the low level +drivers that are registered with it. + +FPGA Region +----------- + +If you are adding a new interface to the FPGA framework, add it on top +of a FPGA region to allow the most reuse of your interface. + +The FPGA Region framework (fpga-region.c) associates managers and +bridges as reconfigurable regions. A region may refer to the whole +FPGA in full reconfiguration or to a partial reconfiguration region. + +The Device Tree FPGA Region support (of-fpga-region.c) handles +reprogramming FPGAs when device tree overlays are applied. diff --git a/Documentation/driver-api/gpio/driver.rst b/Documentation/driver-api/gpio/driver.rst index 505ee906d7d9..cbe0242842d1 100644 --- a/Documentation/driver-api/gpio/driver.rst +++ b/Documentation/driver-api/gpio/driver.rst @@ -44,7 +44,7 @@ common to each controller of that type: - methods to establish GPIO line direction - methods used to access GPIO line values - - method to set electrical configuration to a a given GPIO line + - method to set electrical configuration for a given GPIO line - method to return the IRQ number associated to a given GPIO line - flag saying whether calls to its methods may sleep - optional line names array to identify lines @@ -143,7 +143,7 @@ resistor will make the line tend to high level unless one of the transistors on the rail actively pulls it down. The level on the line will go as high as the VDD on the pull-up resistor, which -may be higher than the level supported by the transistor, achieveing a +may be higher than the level supported by the transistor, achieving a level-shift to the higher VDD. Integrated electronics often have an output driver stage in the form of a CMOS @@ -382,7 +382,7 @@ Real-Time compliance for GPIO IRQ chips Any provider of irqchips needs to be carefully tailored to support Real Time preemption. It is desirable that all irqchips in the GPIO subsystem keep this -in mind and does the proper testing to assure they are real time-enabled. +in mind and do the proper testing to assure they are real time-enabled. So, pay attention on above " RT_FULL:" notes, please. The following is a checklist to follow when preparing a driver for real time-compliance: diff --git a/Documentation/driver-api/gpio/drivers-on-gpio.rst b/Documentation/driver-api/gpio/drivers-on-gpio.rst index 019483868977..7da0c1dd1f7a 100644 --- a/Documentation/driver-api/gpio/drivers-on-gpio.rst +++ b/Documentation/driver-api/gpio/drivers-on-gpio.rst @@ -75,8 +75,8 @@ hardware descriptions such as device tree or ACPI: it from 1-to-0-to-1. If that hardware does not receive its "ping" periodically, it will reset the system. -- gpio-nand: drivers/mtd/nand/gpio.c is used to connect a NAND flash chip to - a set of simple GPIO lines: RDY, NCE, ALE, CLE, NWP. It interacts with the +- gpio-nand: drivers/mtd/nand/raw/gpio.c is used to connect a NAND flash chip + to a set of simple GPIO lines: RDY, NCE, ALE, CLE, NWP. It interacts with the NAND flash MTD subsystem and provides chip access and partition parsing like any other NAND driving hardware. diff --git a/Documentation/driver-api/index.rst b/Documentation/driver-api/index.rst index 6d8352c0f354..f4180e7c7ed5 100644 --- a/Documentation/driver-api/index.rst +++ b/Documentation/driver-api/index.rst @@ -17,7 +17,9 @@ available subsections can be seen below. basics infrastructure pm/index + clk device-io + device_connection dma-buf device_link message-based @@ -49,6 +51,7 @@ available subsections can be seen below. dmaengine/index slimbus soundwire/index + fpga/index .. only:: subproject and html diff --git a/Documentation/driver-api/infrastructure.rst b/Documentation/driver-api/infrastructure.rst index 6d9ff316b608..bee1b9a1702f 100644 --- a/Documentation/driver-api/infrastructure.rst +++ b/Documentation/driver-api/infrastructure.rst @@ -28,7 +28,7 @@ Device Drivers Base .. kernel-doc:: drivers/base/node.c :internal: -.. kernel-doc:: drivers/base/firmware_class.c +.. kernel-doc:: drivers/base/firmware_loader/main.c :export: .. kernel-doc:: drivers/base/transport_class.c diff --git a/Documentation/driver-api/mtdnand.rst b/Documentation/driver-api/mtdnand.rst index 2a5191b6d445..dcd63599f700 100644 --- a/Documentation/driver-api/mtdnand.rst +++ b/Documentation/driver-api/mtdnand.rst @@ -967,10 +967,10 @@ API functions which are exported. Each function has a short description which is marked with an [XXX] identifier. See the chapter "Documentation hints" for an explanation. -.. kernel-doc:: drivers/mtd/nand/nand_base.c +.. kernel-doc:: drivers/mtd/nand/raw/nand_base.c :export: -.. kernel-doc:: drivers/mtd/nand/nand_ecc.c +.. kernel-doc:: drivers/mtd/nand/raw/nand_ecc.c :export: Internal Functions Provided @@ -982,10 +982,10 @@ marked with an [XXX] identifier. See the chapter "Documentation hints" for an explanation. The functions marked with [DEFAULT] might be relevant for a board driver developer. -.. kernel-doc:: drivers/mtd/nand/nand_base.c +.. kernel-doc:: drivers/mtd/nand/raw/nand_base.c :internal: -.. kernel-doc:: drivers/mtd/nand/nand_bbt.c +.. kernel-doc:: drivers/mtd/nand/raw/nand_bbt.c :internal: Credits diff --git a/Documentation/driver-api/soundwire/error_handling.rst b/Documentation/driver-api/soundwire/error_handling.rst new file mode 100644 index 000000000000..aa3a0a23a066 --- /dev/null +++ b/Documentation/driver-api/soundwire/error_handling.rst @@ -0,0 +1,65 @@ +======================== +SoundWire Error Handling +======================== + +The SoundWire PHY was designed with care and errors on the bus are going to +be very unlikely, and if they happen it should be limited to single bit +errors. Examples of this design can be found in the synchronization +mechanism (sync loss after two errors) and short CRCs used for the Bulk +Register Access. + +The errors can be detected with multiple mechanisms: + +1. Bus clash or parity errors: This mechanism relies on low-level detectors + that are independent of the payload and usages, and they cover both control + and audio data. The current implementation only logs such errors. + Improvements could be invalidating an entire programming sequence and + restarting from a known position. In the case of such errors outside of a + control/command sequence, there is no concealment or recovery for audio + data enabled by the SoundWire protocol, the location of the error will also + impact its audibility (most-significant bits will be more impacted in PCM), + and after a number of such errors are detected the bus might be reset. Note + that bus clashes due to programming errors (two streams using the same bit + slots) or electrical issues during the transmit/receive transition cannot + be distinguished, although a recurring bus clash when audio is enabled is a + indication of a bus allocation issue. The interrupt mechanism can also help + identify Slaves which detected a Bus Clash or a Parity Error, but they may + not be responsible for the errors so resetting them individually is not a + viable recovery strategy. + +2. Command status: Each command is associated with a status, which only + covers transmission of the data between devices. The ACK status indicates + that the command was received and will be executed by the end of the + current frame. A NAK indicates that the command was in error and will not + be applied. In case of a bad programming (command sent to non-existent + Slave or to a non-implemented register) or electrical issue, no response + signals the command was ignored. Some Master implementations allow for a + command to be retransmitted several times. If the retransmission fails, + backtracking and restarting the entire programming sequence might be a + solution. Alternatively some implementations might directly issue a bus + reset and re-enumerate all devices. + +3. Timeouts: In a number of cases such as ChannelPrepare or + ClockStopPrepare, the bus driver is supposed to poll a register field until + it transitions to a NotFinished value of zero. The MIPI SoundWire spec 1.1 + does not define timeouts but the MIPI SoundWire DisCo document adds + recommendation on timeouts. If such configurations do not complete, the + driver will return a -ETIMEOUT. Such timeouts are symptoms of a faulty + Slave device and are likely impossible to recover from. + +Errors during global reconfiguration sequences are extremely difficult to +handle: + +1. BankSwitch: An error during the last command issuing a BankSwitch is + difficult to backtrack from. Retransmitting the Bank Switch command may be + possible in a single segment setup, but this can lead to synchronization + problems when enabling multiple bus segments (a command with side effects + such as frame reconfiguration would be handled at different times). A global + hard-reset might be the best solution. + +Note that SoundWire does not provide a mechanism to detect illegal values +written in valid registers. In a number of cases the standard even mentions +that the Slave might behave in implementation-defined ways. The bus +implementation does not provide a recovery mechanism for such errors, Slave +or Master driver implementers are responsible for writing valid values in +valid registers and implement additional range checking if needed. diff --git a/Documentation/driver-api/soundwire/index.rst b/Documentation/driver-api/soundwire/index.rst index 647e94654752..6db026028f27 100644 --- a/Documentation/driver-api/soundwire/index.rst +++ b/Documentation/driver-api/soundwire/index.rst @@ -6,6 +6,9 @@ SoundWire Documentation :maxdepth: 1 summary + stream + error_handling + locking .. only:: subproject diff --git a/Documentation/driver-api/soundwire/locking.rst b/Documentation/driver-api/soundwire/locking.rst new file mode 100644 index 000000000000..253f73555255 --- /dev/null +++ b/Documentation/driver-api/soundwire/locking.rst @@ -0,0 +1,106 @@ +================= +SoundWire Locking +================= + +This document explains locking mechanism of the SoundWire Bus. Bus uses +following locks in order to avoid race conditions in Bus operations on +shared resources. + + - Bus lock + + - Message lock + +Bus lock +======== + +SoundWire Bus lock is a mutex and is part of Bus data structure +(sdw_bus) which is used for every Bus instance. This lock is used to +serialize each of the following operations(s) within SoundWire Bus instance. + + - Addition and removal of Slave(s), changing Slave status. + + - Prepare, Enable, Disable and De-prepare stream operations. + + - Access of Stream data structure. + +Message lock +============ + +SoundWire message transfer lock. This mutex is part of +Bus data structure (sdw_bus). This lock is used to serialize the message +transfers (read/write) within a SoundWire Bus instance. + +Below examples show how locks are acquired. + +Example 1 +--------- + +Message transfer. + + 1. For every message transfer + + a. Acquire Message lock. + + b. Transfer message (Read/Write) to Slave1 or broadcast message on + Bus in case of bank switch. + + c. Release Message lock :: + + +----------+ +---------+ + | | | | + | Bus | | Master | + | | | Driver | + | | | | + +----+-----+ +----+----+ + | | + | bus->ops->xfer_msg() | + <-------------------------------+ a. Acquire Message lock + | | b. Transfer message + | | + +-------------------------------> c. Release Message lock + | return success/error | d. Return success/error + | | + + + + +Example 2 +--------- + +Prepare operation. + + 1. Acquire lock for Bus instance associated with Master 1. + + 2. For every message transfer in Prepare operation + + a. Acquire Message lock. + + b. Transfer message (Read/Write) to Slave1 or broadcast message on + Bus in case of bank switch. + + c. Release Message lock. + + 3. Release lock for Bus instance associated with Master 1 :: + + +----------+ +---------+ + | | | | + | Bus | | Master | + | | | Driver | + | | | | + +----+-----+ +----+----+ + | | + | sdw_prepare_stream() | + <-------------------------------+ 1. Acquire bus lock + | | 2. Perform stream prepare + | | + | | + | bus->ops->xfer_msg() | + <-------------------------------+ a. Acquire Message lock + | | b. Transfer message + | | + +-------------------------------> c. Release Message lock + | return success/error | d. Return success/error + | | + | | + | return success/error | 3. Release bus lock + +-------------------------------> 4. Return success/error + | | + + + diff --git a/Documentation/driver-api/soundwire/stream.rst b/Documentation/driver-api/soundwire/stream.rst new file mode 100644 index 000000000000..29121aa55fb9 --- /dev/null +++ b/Documentation/driver-api/soundwire/stream.rst @@ -0,0 +1,372 @@ +========================= +Audio Stream in SoundWire +========================= + +An audio stream is a logical or virtual connection created between + + (1) System memory buffer(s) and Codec(s) + + (2) DSP memory buffer(s) and Codec(s) + + (3) FIFO(s) and Codec(s) + + (4) Codec(s) and Codec(s) + +which is typically driven by a DMA(s) channel through the data link. An +audio stream contains one or more channels of data. All channels within +stream must have same sample rate and same sample size. + +Assume a stream with two channels (Left & Right) is opened using SoundWire +interface. Below are some ways a stream can be represented in SoundWire. + +Stream Sample in memory (System memory, DSP memory or FIFOs) :: + + ------------------------- + | L | R | L | R | L | R | + ------------------------- + +Example 1: Stereo Stream with L and R channels is rendered from Master to +Slave. Both Master and Slave is using single port. :: + + +---------------+ Clock Signal +---------------+ + | Master +----------------------------------+ Slave | + | Interface | | Interface | + | | | 1 | + | | Data Signal | | + | L + R +----------------------------------+ L + R | + | (Data) | Data Direction | (Data) | + +---------------+ +-----------------------> +---------------+ + + +Example 2: Stereo Stream with L and R channels is captured from Slave to +Master. Both Master and Slave is using single port. :: + + + +---------------+ Clock Signal +---------------+ + | Master +----------------------------------+ Slave | + | Interface | | Interface | + | | | 1 | + | | Data Signal | | + | L + R +----------------------------------+ L + R | + | (Data) | Data Direction | (Data) | + +---------------+ <-----------------------+ +---------------+ + + +Example 3: Stereo Stream with L and R channels is rendered by Master. Each +of the L and R channel is received by two different Slaves. Master and both +Slaves are using single port. :: + + +---------------+ Clock Signal +---------------+ + | Master +---------+------------------------+ Slave | + | Interface | | | Interface | + | | | | 1 | + | | | Data Signal | | + | L + R +---+------------------------------+ L | + | (Data) | | | Data Direction | (Data) | + +---------------+ | | +-------------> +---------------+ + | | + | | + | | +---------------+ + | +----------------------> | Slave | + | | Interface | + | | 2 | + | | | + +----------------------------> | R | + | (Data) | + +---------------+ + + +Example 4: Stereo Stream with L and R channel is rendered by two different +Ports of the Master and is received by only single Port of the Slave +interface. :: + + +--------------------+ + | | + | +--------------+ +----------------+ + | | || | | + | | Data Port || L Channel | | + | | 1 |------------+ | | + | | L Channel || | +-----+----+ | + | | (Data) || | L + R Channel || Data | | + | Master +----------+ | +---+---------> || Port | | + | Interface | | || 1 | | + | +--------------+ | || | | + | | || | +----------+ | + | | Data Port |------------+ | | + | | 2 || R Channel | Slave | + | | R Channel || | Interface | + | | (Data) || | 1 | + | +--------------+ Clock Signal | L + R | + | +---------------------------> | (Data) | + +--------------------+ | | + +----------------+ + +SoundWire Stream Management flow +================================ + +Stream definitions +------------------ + + (1) Current stream: This is classified as the stream on which operation has + to be performed like prepare, enable, disable, de-prepare etc. + + (2) Active stream: This is classified as the stream which is already active + on Bus other than current stream. There can be multiple active streams + on the Bus. + +SoundWire Bus manages stream operations for each stream getting +rendered/captured on the SoundWire Bus. This section explains Bus operations +done for each of the stream allocated/released on Bus. Following are the +stream states maintained by the Bus for each of the audio stream. + + +SoundWire stream states +----------------------- + +Below shows the SoundWire stream states and state transition diagram. :: + + +-----------+ +------------+ +----------+ +----------+ + | ALLOCATED +---->| CONFIGURED +---->| PREPARED +---->| ENABLED | + | STATE | | STATE | | STATE | | STATE | + +-----------+ +------------+ +----------+ +----+-----+ + ^ + | + | + v + +----------+ +------------+ +----+-----+ + | RELEASED |<----------+ DEPREPARED |<-------+ DISABLED | + | STATE | | STATE | | STATE | + +----------+ +------------+ +----------+ + +NOTE: State transition between prepare and deprepare is supported in Spec +but not in the software (subsystem) + +NOTE2: Stream state transition checks need to be handled by caller +framework, for example ALSA/ASoC. No checks for stream transition exist in +SoundWire subsystem. + +Stream State Operations +----------------------- + +Below section explains the operations done by the Bus on Master(s) and +Slave(s) as part of stream state transitions. + +SDW_STREAM_ALLOCATED +~~~~~~~~~~~~~~~~~~~~ + +Allocation state for stream. This is the entry state +of the stream. Operations performed before entering in this state: + + (1) A stream runtime is allocated for the stream. This stream + runtime is used as a reference for all the operations performed + on the stream. + + (2) The resources required for holding stream runtime information are + allocated and initialized. This holds all stream related information + such as stream type (PCM/PDM) and parameters, Master and Slave + interface associated with the stream, stream state etc. + +After all above operations are successful, stream state is set to +``SDW_STREAM_ALLOCATED``. + +Bus implements below API for allocate a stream which needs to be called once +per stream. From ASoC DPCM framework, this stream state maybe linked to +.startup() operation. + + .. code-block:: c + int sdw_alloc_stream(char * stream_name); + + +SDW_STREAM_CONFIGURED +~~~~~~~~~~~~~~~~~~~~~ + +Configuration state of stream. Operations performed before entering in +this state: + + (1) The resources allocated for stream information in SDW_STREAM_ALLOCATED + state are updated here. This includes stream parameters, Master(s) + and Slave(s) runtime information associated with current stream. + + (2) All the Master(s) and Slave(s) associated with current stream provide + the port information to Bus which includes port numbers allocated by + Master(s) and Slave(s) for current stream and their channel mask. + +After all above operations are successful, stream state is set to +``SDW_STREAM_CONFIGURED``. + +Bus implements below APIs for CONFIG state which needs to be called by +the respective Master(s) and Slave(s) associated with stream. These APIs can +only be invoked once by respective Master(s) and Slave(s). From ASoC DPCM +framework, this stream state is linked to .hw_params() operation. + + .. code-block:: c + int sdw_stream_add_master(struct sdw_bus * bus, + struct sdw_stream_config * stream_config, + struct sdw_ports_config * ports_config, + struct sdw_stream_runtime * stream); + + int sdw_stream_add_slave(struct sdw_slave * slave, + struct sdw_stream_config * stream_config, + struct sdw_ports_config * ports_config, + struct sdw_stream_runtime * stream); + + +SDW_STREAM_PREPARED +~~~~~~~~~~~~~~~~~~~ + +Prepare state of stream. Operations performed before entering in this state: + + (1) Bus parameters such as bandwidth, frame shape, clock frequency, + are computed based on current stream as well as already active + stream(s) on Bus. Re-computation is required to accommodate current + stream on the Bus. + + (2) Transport and port parameters of all Master(s) and Slave(s) port(s) are + computed for the current as well as already active stream based on frame + shape and clock frequency computed in step 1. + + (3) Computed Bus and transport parameters are programmed in Master(s) and + Slave(s) registers. The banked registers programming is done on the + alternate bank (bank currently unused). Port(s) are enabled for the + already active stream(s) on the alternate bank (bank currently unused). + This is done in order to not disrupt already active stream(s). + + (4) Once all the values are programmed, Bus initiates switch to alternate + bank where all new values programmed gets into effect. + + (5) Ports of Master(s) and Slave(s) for current stream are prepared by + programming PrepareCtrl register. + +After all above operations are successful, stream state is set to +``SDW_STREAM_PREPARED``. + +Bus implements below API for PREPARE state which needs to be called once per +stream. From ASoC DPCM framework, this stream state is linked to +.prepare() operation. + + .. code-block:: c + int sdw_prepare_stream(struct sdw_stream_runtime * stream); + + +SDW_STREAM_ENABLED +~~~~~~~~~~~~~~~~~~ + +Enable state of stream. The data port(s) are enabled upon entering this state. +Operations performed before entering in this state: + + (1) All the values computed in SDW_STREAM_PREPARED state are programmed + in alternate bank (bank currently unused). It includes programming of + already active stream(s) as well. + + (2) All the Master(s) and Slave(s) port(s) for the current stream are + enabled on alternate bank (bank currently unused) by programming + ChannelEn register. + + (3) Once all the values are programmed, Bus initiates switch to alternate + bank where all new values programmed gets into effect and port(s) + associated with current stream are enabled. + +After all above operations are successful, stream state is set to +``SDW_STREAM_ENABLED``. + +Bus implements below API for ENABLE state which needs to be called once per +stream. From ASoC DPCM framework, this stream state is linked to +.trigger() start operation. + + .. code-block:: c + int sdw_enable_stream(struct sdw_stream_runtime * stream); + +SDW_STREAM_DISABLED +~~~~~~~~~~~~~~~~~~~ + +Disable state of stream. The data port(s) are disabled upon exiting this state. +Operations performed before entering in this state: + + (1) All the Master(s) and Slave(s) port(s) for the current stream are + disabled on alternate bank (bank currently unused) by programming + ChannelEn register. + + (2) All the current configuration of Bus and active stream(s) are programmed + into alternate bank (bank currently unused). + + (3) Once all the values are programmed, Bus initiates switch to alternate + bank where all new values programmed gets into effect and port(s) associated + with current stream are disabled. + +After all above operations are successful, stream state is set to +``SDW_STREAM_DISABLED``. + +Bus implements below API for DISABLED state which needs to be called once +per stream. From ASoC DPCM framework, this stream state is linked to +.trigger() stop operation. + + .. code-block:: c + int sdw_disable_stream(struct sdw_stream_runtime * stream); + + +SDW_STREAM_DEPREPARED +~~~~~~~~~~~~~~~~~~~~~ + +De-prepare state of stream. Operations performed before entering in this +state: + + (1) All the port(s) of Master(s) and Slave(s) for current stream are + de-prepared by programming PrepareCtrl register. + + (2) The payload bandwidth of current stream is reduced from the total + bandwidth requirement of bus and new parameters calculated and + applied by performing bank switch etc. + +After all above operations are successful, stream state is set to +``SDW_STREAM_DEPREPARED``. + +Bus implements below API for DEPREPARED state which needs to be called once +per stream. From ASoC DPCM framework, this stream state is linked to +.trigger() stop operation. + + .. code-block:: c + int sdw_deprepare_stream(struct sdw_stream_runtime * stream); + + +SDW_STREAM_RELEASED +~~~~~~~~~~~~~~~~~~~ + +Release state of stream. Operations performed before entering in this state: + + (1) Release port resources for all Master(s) and Slave(s) port(s) + associated with current stream. + + (2) Release Master(s) and Slave(s) runtime resources associated with + current stream. + + (3) Release stream runtime resources associated with current stream. + +After all above operations are successful, stream state is set to +``SDW_STREAM_RELEASED``. + +Bus implements below APIs for RELEASE state which needs to be called by +all the Master(s) and Slave(s) associated with stream. From ASoC DPCM +framework, this stream state is linked to .hw_free() operation. + + .. code-block:: c + int sdw_stream_remove_master(struct sdw_bus * bus, + struct sdw_stream_runtime * stream); + int sdw_stream_remove_slave(struct sdw_slave * slave, + struct sdw_stream_runtime * stream); + + +The .shutdown() ASoC DPCM operation calls below Bus API to release +stream assigned as part of ALLOCATED state. + +In .shutdown() the data structure maintaining stream state are freed up. + + .. code-block:: c + void sdw_release_stream(struct sdw_stream_runtime * stream); + +Not Supported +============= + +1. A single port with multiple channels supported cannot be used between two +streams or across stream. For example a port with 4 channels cannot be used +to handle 2 independent stereo streams even though it's possible in theory +in SoundWire. diff --git a/Documentation/driver-api/uio-howto.rst b/Documentation/driver-api/uio-howto.rst index 92056c20e070..fb2eb73be4a3 100644 --- a/Documentation/driver-api/uio-howto.rst +++ b/Documentation/driver-api/uio-howto.rst @@ -711,7 +711,8 @@ The vmbus device regions are mapped into uio device resources: If a subchannel is created by a request to host, then the uio_hv_generic device driver will create a sysfs binary file for the per-channel ring buffer. -For example: +For example:: + /sys/bus/vmbus/devices/3811fe4d-0fa0-4b62-981a-74fc1084c757/channels/21/ring Further information diff --git a/Documentation/driver-api/usb/dwc3.rst b/Documentation/driver-api/usb/dwc3.rst index c3dc84a50ce5..8b36ff11cef9 100644 --- a/Documentation/driver-api/usb/dwc3.rst +++ b/Documentation/driver-api/usb/dwc3.rst @@ -674,9 +674,8 @@ operations, both of which can be traced. Format is:: __entry->flags & DWC3_EP_ENABLED ? 'E' : 'e', __entry->flags & DWC3_EP_STALL ? 'S' : 's', __entry->flags & DWC3_EP_WEDGE ? 'W' : 'w', - __entry->flags & DWC3_EP_BUSY ? 'B' : 'b', + __entry->flags & DWC3_EP_TRANSFER_STARTED ? 'B' : 'b', __entry->flags & DWC3_EP_PENDING_REQUEST ? 'P' : 'p', - __entry->flags & DWC3_EP_MISSED_ISOC ? 'M' : 'm', __entry->flags & DWC3_EP_END_TRANSFER_PENDING ? 'E' : 'e', __entry->direction ? '<' : '>' ) diff --git a/Documentation/driver-api/usb/typec.rst b/Documentation/driver-api/usb/typec.rst index feb31946490b..48ff58095f11 100644 --- a/Documentation/driver-api/usb/typec.rst +++ b/Documentation/driver-api/usb/typec.rst @@ -210,7 +210,7 @@ If the connector is dual-role capable, there may also be a switch for the data role. USB Type-C Connector Class does not supply separate API for them. The port drivers can use USB Role Class API with those. -Illustration of the muxes behind a connector that supports an alternate mode: +Illustration of the muxes behind a connector that supports an alternate mode:: ------------------------ | Connector | diff --git a/Documentation/features/lib/strncasecmp/arch-support.txt b/Documentation/features/core/cBPF-JIT/arch-support.txt index 4f3a6a0e4e68..90459cdde314 100644 --- a/Documentation/features/lib/strncasecmp/arch-support.txt +++ b/Documentation/features/core/cBPF-JIT/arch-support.txt @@ -1,7 +1,7 @@ # -# Feature name: strncasecmp -# Kconfig: __HAVE_ARCH_STRNCASECMP -# description: arch provides an optimized strncasecmp() function +# Feature name: cBPF-JIT +# Kconfig: HAVE_CBPF_JIT +# description: arch supports cBPF JIT optimizations # ----------------------- | arch |status| @@ -16,14 +16,16 @@ | ia64: | TODO | | m68k: | TODO | | microblaze: | TODO | - | mips: | TODO | + | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | - | powerpc: | TODO | + | powerpc: | ok | + | riscv: | TODO | | s390: | TODO | | sh: | TODO | - | sparc: | TODO | + | sparc: | ok | | um: | TODO | | unicore32: | TODO | | x86: | TODO | diff --git a/Documentation/features/core/BPF-JIT/arch-support.txt b/Documentation/features/core/eBPF-JIT/arch-support.txt index 0b96b4e1e7d4..c90a0382fe66 100644 --- a/Documentation/features/core/BPF-JIT/arch-support.txt +++ b/Documentation/features/core/eBPF-JIT/arch-support.txt @@ -1,7 +1,7 @@ # -# Feature name: BPF-JIT -# Kconfig: HAVE_BPF_JIT -# description: arch supports BPF JIT optimizations +# Feature name: eBPF-JIT +# Kconfig: HAVE_EBPF_JIT +# description: arch supports eBPF JIT optimizations # ----------------------- | arch |status| @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | TODO | | sparc: | ok | diff --git a/Documentation/features/core/generic-idle-thread/arch-support.txt b/Documentation/features/core/generic-idle-thread/arch-support.txt index 372a2b18a617..0ef6acdb991c 100644 --- a/Documentation/features/core/generic-idle-thread/arch-support.txt +++ b/Documentation/features/core/generic-idle-thread/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | - | openrisc: | TODO | + | openrisc: | ok | | parisc: | ok | | powerpc: | ok | + | riscv: | ok | | s390: | ok | | sh: | ok | | sparc: | ok | diff --git a/Documentation/features/core/jump-labels/arch-support.txt b/Documentation/features/core/jump-labels/arch-support.txt index ad97217b003b..27cbd63abfd2 100644 --- a/Documentation/features/core/jump-labels/arch-support.txt +++ b/Documentation/features/core/jump-labels/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | TODO | | sparc: | ok | diff --git a/Documentation/features/core/tracehook/arch-support.txt b/Documentation/features/core/tracehook/arch-support.txt index 36ee7bef5d18..f44c274e40ed 100644 --- a/Documentation/features/core/tracehook/arch-support.txt +++ b/Documentation/features/core/tracehook/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | ok | | nios2: | ok | | openrisc: | ok | | parisc: | ok | | powerpc: | ok | + | riscv: | ok | | s390: | ok | | sh: | ok | | sparc: | ok | diff --git a/Documentation/features/debug/KASAN/arch-support.txt b/Documentation/features/debug/KASAN/arch-support.txt index f5c99fa576d3..282ecc8ea1da 100644 --- a/Documentation/features/debug/KASAN/arch-support.txt +++ b/Documentation/features/debug/KASAN/arch-support.txt @@ -17,15 +17,17 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | TODO | + | riscv: | TODO | | s390: | TODO | | sh: | TODO | | sparc: | TODO | | um: | TODO | | unicore32: | TODO | - | x86: | ok | 64-bit only + | x86: | ok | | xtensa: | ok | ----------------------- diff --git a/Documentation/features/debug/gcov-profile-all/arch-support.txt b/Documentation/features/debug/gcov-profile-all/arch-support.txt index 5170a9934843..01b2b3004e0a 100644 --- a/Documentation/features/debug/gcov-profile-all/arch-support.txt +++ b/Documentation/features/debug/gcov-profile-all/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | ok | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | ok | | sparc: | TODO | diff --git a/Documentation/features/debug/kgdb/arch-support.txt b/Documentation/features/debug/kgdb/arch-support.txt index 13b6e994ae1f..3b4dff22329f 100644 --- a/Documentation/features/debug/kgdb/arch-support.txt +++ b/Documentation/features/debug/kgdb/arch-support.txt @@ -11,16 +11,18 @@ | arm: | ok | | arm64: | ok | | c6x: | TODO | - | h8300: | TODO | + | h8300: | ok | | hexagon: | ok | | ia64: | TODO | | m68k: | TODO | | microblaze: | ok | | mips: | ok | + | nds32: | TODO | | nios2: | ok | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | TODO | | sh: | ok | | sparc: | ok | diff --git a/Documentation/features/debug/kprobes-on-ftrace/arch-support.txt b/Documentation/features/debug/kprobes-on-ftrace/arch-support.txt index 419bb38820e7..7e963d0ae646 100644 --- a/Documentation/features/debug/kprobes-on-ftrace/arch-support.txt +++ b/Documentation/features/debug/kprobes-on-ftrace/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | TODO | | sh: | TODO | | sparc: | TODO | diff --git a/Documentation/features/debug/kprobes/arch-support.txt b/Documentation/features/debug/kprobes/arch-support.txt index 52b3ace0a030..4ada027faf16 100644 --- a/Documentation/features/debug/kprobes/arch-support.txt +++ b/Documentation/features/debug/kprobes/arch-support.txt @@ -9,7 +9,7 @@ | alpha: | TODO | | arc: | ok | | arm: | ok | - | arm64: | TODO | + | arm64: | ok | | c6x: | TODO | | h8300: | TODO | | hexagon: | TODO | @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | ok | | s390: | ok | | sh: | ok | | sparc: | ok | diff --git a/Documentation/features/debug/kretprobes/arch-support.txt b/Documentation/features/debug/kretprobes/arch-support.txt index 180d24419518..044e13fcca5d 100644 --- a/Documentation/features/debug/kretprobes/arch-support.txt +++ b/Documentation/features/debug/kretprobes/arch-support.txt @@ -9,7 +9,7 @@ | alpha: | TODO | | arc: | ok | | arm: | ok | - | arm64: | TODO | + | arm64: | ok | | c6x: | TODO | | h8300: | TODO | | hexagon: | TODO | @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | ok | | sparc: | ok | diff --git a/Documentation/features/debug/optprobes/arch-support.txt b/Documentation/features/debug/optprobes/arch-support.txt index 0a1241f45e41..dce7669c918f 100644 --- a/Documentation/features/debug/optprobes/arch-support.txt +++ b/Documentation/features/debug/optprobes/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | - | powerpc: | TODO | + | powerpc: | ok | + | riscv: | TODO | | s390: | TODO | | sh: | TODO | | sparc: | TODO | diff --git a/Documentation/features/debug/stackprotector/arch-support.txt b/Documentation/features/debug/stackprotector/arch-support.txt index 570019572383..74b89a9c8b3a 100644 --- a/Documentation/features/debug/stackprotector/arch-support.txt +++ b/Documentation/features/debug/stackprotector/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | TODO | + | riscv: | TODO | | s390: | TODO | | sh: | ok | | sparc: | TODO | diff --git a/Documentation/features/debug/uprobes/arch-support.txt b/Documentation/features/debug/uprobes/arch-support.txt index 0b8d922eb799..1a3f9d3229bf 100644 --- a/Documentation/features/debug/uprobes/arch-support.txt +++ b/Documentation/features/debug/uprobes/arch-support.txt @@ -9,7 +9,7 @@ | alpha: | TODO | | arc: | TODO | | arm: | ok | - | arm64: | TODO | + | arm64: | ok | | c6x: | TODO | | h8300: | TODO | | hexagon: | TODO | @@ -17,13 +17,15 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | TODO | - | sparc: | TODO | + | sparc: | ok | | um: | TODO | | unicore32: | TODO | | x86: | ok | diff --git a/Documentation/features/debug/user-ret-profiler/arch-support.txt b/Documentation/features/debug/user-ret-profiler/arch-support.txt index 13852ae62e9e..1d78d1069a5f 100644 --- a/Documentation/features/debug/user-ret-profiler/arch-support.txt +++ b/Documentation/features/debug/user-ret-profiler/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | TODO | + | riscv: | TODO | | s390: | TODO | | sh: | TODO | | sparc: | TODO | diff --git a/Documentation/features/io/dma-api-debug/arch-support.txt b/Documentation/features/io/dma-api-debug/arch-support.txt deleted file mode 100644 index e438ed675623..000000000000 --- a/Documentation/features/io/dma-api-debug/arch-support.txt +++ /dev/null @@ -1,31 +0,0 @@ -# -# Feature name: dma-api-debug -# Kconfig: HAVE_DMA_API_DEBUG -# description: arch supports DMA debug facilities -# - ----------------------- - | arch |status| - ----------------------- - | alpha: | TODO | - | arc: | TODO | - | arm: | ok | - | arm64: | ok | - | c6x: | ok | - | h8300: | TODO | - | hexagon: | TODO | - | ia64: | ok | - | m68k: | TODO | - | microblaze: | ok | - | mips: | ok | - | nios2: | TODO | - | openrisc: | TODO | - | parisc: | TODO | - | powerpc: | ok | - | s390: | ok | - | sh: | ok | - | sparc: | ok | - | um: | TODO | - | unicore32: | TODO | - | x86: | ok | - | xtensa: | ok | - ----------------------- diff --git a/Documentation/features/io/dma-contiguous/arch-support.txt b/Documentation/features/io/dma-contiguous/arch-support.txt index 47f64a433df0..30c072d2b67c 100644 --- a/Documentation/features/io/dma-contiguous/arch-support.txt +++ b/Documentation/features/io/dma-contiguous/arch-support.txt @@ -17,11 +17,13 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | TODO | - | s390: | TODO | + | riscv: | ok | + | s390: | ok | | sh: | TODO | | sparc: | TODO | | um: | TODO | diff --git a/Documentation/features/io/sg-chain/arch-support.txt b/Documentation/features/io/sg-chain/arch-support.txt index 07f357fadbff..6554f0372c3f 100644 --- a/Documentation/features/io/sg-chain/arch-support.txt +++ b/Documentation/features/io/sg-chain/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | TODO | | sparc: | ok | diff --git a/Documentation/features/locking/cmpxchg-local/arch-support.txt b/Documentation/features/locking/cmpxchg-local/arch-support.txt index 482a0b09d1f8..51704a2dc8d1 100644 --- a/Documentation/features/locking/cmpxchg-local/arch-support.txt +++ b/Documentation/features/locking/cmpxchg-local/arch-support.txt @@ -9,7 +9,7 @@ | alpha: | TODO | | arc: | TODO | | arm: | TODO | - | arm64: | TODO | + | arm64: | ok | | c6x: | TODO | | h8300: | TODO | | hexagon: | TODO | @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | TODO | + | riscv: | TODO | | s390: | ok | | sh: | TODO | | sparc: | TODO | diff --git a/Documentation/features/locking/lockdep/arch-support.txt b/Documentation/features/locking/lockdep/arch-support.txt index bb35c5ba6286..bd39c5edd460 100644 --- a/Documentation/features/locking/lockdep/arch-support.txt +++ b/Documentation/features/locking/lockdep/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | ok | | mips: | ok | + | nds32: | ok | | nios2: | TODO | - | openrisc: | TODO | + | openrisc: | ok | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | ok | | sparc: | ok | diff --git a/Documentation/features/locking/queued-rwlocks/arch-support.txt b/Documentation/features/locking/queued-rwlocks/arch-support.txt index 627e9a6b2db9..da7aff3bee0b 100644 --- a/Documentation/features/locking/queued-rwlocks/arch-support.txt +++ b/Documentation/features/locking/queued-rwlocks/arch-support.txt @@ -9,21 +9,23 @@ | alpha: | TODO | | arc: | TODO | | arm: | TODO | - | arm64: | TODO | + | arm64: | ok | | c6x: | TODO | | h8300: | TODO | | hexagon: | TODO | | ia64: | TODO | | m68k: | TODO | | microblaze: | TODO | - | mips: | TODO | + | mips: | ok | + | nds32: | TODO | | nios2: | TODO | - | openrisc: | TODO | + | openrisc: | ok | | parisc: | TODO | | powerpc: | TODO | + | riscv: | TODO | | s390: | TODO | | sh: | TODO | - | sparc: | TODO | + | sparc: | ok | | um: | TODO | | unicore32: | TODO | | x86: | ok | diff --git a/Documentation/features/locking/queued-spinlocks/arch-support.txt b/Documentation/features/locking/queued-spinlocks/arch-support.txt index 9edda216cdfb..478e9101322c 100644 --- a/Documentation/features/locking/queued-spinlocks/arch-support.txt +++ b/Documentation/features/locking/queued-spinlocks/arch-support.txt @@ -16,14 +16,16 @@ | ia64: | TODO | | m68k: | TODO | | microblaze: | TODO | - | mips: | TODO | + | mips: | ok | + | nds32: | TODO | | nios2: | TODO | - | openrisc: | TODO | + | openrisc: | ok | | parisc: | TODO | | powerpc: | TODO | + | riscv: | TODO | | s390: | TODO | | sh: | TODO | - | sparc: | TODO | + | sparc: | ok | | um: | TODO | | unicore32: | TODO | | x86: | ok | diff --git a/Documentation/features/locking/rwsem-optimized/arch-support.txt b/Documentation/features/locking/rwsem-optimized/arch-support.txt index 8d9afb10b16e..e54b1f1a8091 100644 --- a/Documentation/features/locking/rwsem-optimized/arch-support.txt +++ b/Documentation/features/locking/rwsem-optimized/arch-support.txt @@ -1,6 +1,6 @@ # # Feature name: rwsem-optimized -# Kconfig: Optimized asm/rwsem.h +# Kconfig: !RWSEM_GENERIC_SPINLOCK # description: arch provides optimized rwsem APIs # ----------------------- @@ -8,8 +8,8 @@ ----------------------- | alpha: | ok | | arc: | TODO | - | arm: | TODO | - | arm64: | TODO | + | arm: | ok | + | arm64: | ok | | c6x: | TODO | | h8300: | TODO | | hexagon: | TODO | @@ -17,14 +17,16 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | TODO | + | riscv: | TODO | | s390: | ok | | sh: | ok | | sparc: | ok | - | um: | TODO | + | um: | ok | | unicore32: | TODO | | x86: | ok | | xtensa: | ok | diff --git a/Documentation/features/perf/kprobes-event/arch-support.txt b/Documentation/features/perf/kprobes-event/arch-support.txt index d01239ee34b3..7331402d1887 100644 --- a/Documentation/features/perf/kprobes-event/arch-support.txt +++ b/Documentation/features/perf/kprobes-event/arch-support.txt @@ -9,7 +9,7 @@ | alpha: | TODO | | arc: | TODO | | arm: | ok | - | arm64: | TODO | + | arm64: | ok | | c6x: | TODO | | h8300: | TODO | | hexagon: | ok | @@ -17,13 +17,15 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | ok | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | ok | - | sparc: | TODO | + | sparc: | ok | | um: | TODO | | unicore32: | TODO | | x86: | ok | diff --git a/Documentation/features/perf/perf-regs/arch-support.txt b/Documentation/features/perf/perf-regs/arch-support.txt index 458faba5311a..53feeee6cdad 100644 --- a/Documentation/features/perf/perf-regs/arch-support.txt +++ b/Documentation/features/perf/perf-regs/arch-support.txt @@ -17,11 +17,13 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | - | s390: | TODO | + | riscv: | TODO | + | s390: | ok | | sh: | TODO | | sparc: | TODO | | um: | TODO | diff --git a/Documentation/features/perf/perf-stackdump/arch-support.txt b/Documentation/features/perf/perf-stackdump/arch-support.txt index 545d01c69c88..16164348e0ea 100644 --- a/Documentation/features/perf/perf-stackdump/arch-support.txt +++ b/Documentation/features/perf/perf-stackdump/arch-support.txt @@ -17,11 +17,13 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | - | s390: | TODO | + | riscv: | TODO | + | s390: | ok | | sh: | TODO | | sparc: | TODO | | um: | TODO | diff --git a/Documentation/features/sched/membarrier-sync-core/arch-support.txt b/Documentation/features/sched/membarrier-sync-core/arch-support.txt index 85a6c9d4571c..dbdf62907703 100644 --- a/Documentation/features/sched/membarrier-sync-core/arch-support.txt +++ b/Documentation/features/sched/membarrier-sync-core/arch-support.txt @@ -40,10 +40,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | TODO | + | riscv: | TODO | | s390: | TODO | | sh: | TODO | | sparc: | TODO | diff --git a/Documentation/features/sched/numa-balancing/arch-support.txt b/Documentation/features/sched/numa-balancing/arch-support.txt index 347508863872..c68bb2c2cb62 100644 --- a/Documentation/features/sched/numa-balancing/arch-support.txt +++ b/Documentation/features/sched/numa-balancing/arch-support.txt @@ -9,7 +9,7 @@ | alpha: | TODO | | arc: | .. | | arm: | .. | - | arm64: | .. | + | arm64: | ok | | c6x: | .. | | h8300: | .. | | hexagon: | .. | @@ -17,11 +17,13 @@ | m68k: | .. | | microblaze: | .. | | mips: | TODO | + | nds32: | TODO | | nios2: | .. | | openrisc: | .. | | parisc: | .. | | powerpc: | ok | - | s390: | .. | + | riscv: | TODO | + | s390: | ok | | sh: | .. | | sparc: | TODO | | um: | .. | diff --git a/Documentation/features/scripts/features-refresh.sh b/Documentation/features/scripts/features-refresh.sh new file mode 100755 index 000000000000..9e72d38a0720 --- /dev/null +++ b/Documentation/features/scripts/features-refresh.sh @@ -0,0 +1,98 @@ +# +# Small script that refreshes the kernel feature support status in place. +# + +for F_FILE in Documentation/features/*/*/arch-support.txt; do + F=$(grep "^# Kconfig:" "$F_FILE" | cut -c26-) + + # + # Each feature F is identified by a pair (O, K), where 'O' can + # be either the empty string (for 'nop') or "not" (the logical + # negation operator '!'); other operators are not supported. + # + O="" + K=$F + if [[ "$F" == !* ]]; then + O="not" + K=$(echo $F | sed -e 's/^!//g') + fi + + # + # F := (O, K) is 'valid' iff there is a Kconfig file (for some + # arch) which contains K. + # + # Notice that this definition entails an 'asymmetry' between + # the case 'O = ""' and the case 'O = "not"'. E.g., F may be + # _invalid_ if: + # + # [case 'O = ""'] + # 1) no arch provides support for F, + # 2) K does not exist (e.g., it was renamed/mis-typed); + # + # [case 'O = "not"'] + # 3) all archs provide support for F, + # 4) as in (2). + # + # The rationale for adopting this definition (and, thus, for + # keeping the asymmetry) is: + # + # We want to be able to 'detect' (2) (or (4)). + # + # (1) and (3) may further warn the developers about the fact + # that K can be removed. + # + F_VALID="false" + for ARCH_DIR in arch/*/; do + K_FILES=$(find $ARCH_DIR -name "Kconfig*") + K_GREP=$(grep "$K" $K_FILES) + if [ ! -z "$K_GREP" ]; then + F_VALID="true" + break + fi + done + if [ "$F_VALID" = "false" ]; then + printf "WARNING: '%s' is not a valid Kconfig\n" "$F" + fi + + T_FILE="$F_FILE.tmp" + grep "^#" $F_FILE > $T_FILE + echo " -----------------------" >> $T_FILE + echo " | arch |status|" >> $T_FILE + echo " -----------------------" >> $T_FILE + for ARCH_DIR in arch/*/; do + ARCH=$(echo $ARCH_DIR | sed -e 's/arch//g' | sed -e 's/\///g') + K_FILES=$(find $ARCH_DIR -name "Kconfig*") + K_GREP=$(grep "$K" $K_FILES) + # + # Arch support status values for (O, K) are updated according + # to the following rules. + # + # - ("", K) is 'supported by a given arch', if there is a + # Kconfig file for that arch which contains K; + # + # - ("not", K) is 'supported by a given arch', if there is + # no Kconfig file for that arch which contains K; + # + # - otherwise: preserve the previous status value (if any), + # default to 'not yet supported'. + # + # Notice that, according these rules, invalid features may be + # updated/modified. + # + if [ "$O" = "" ] && [ ! -z "$K_GREP" ]; then + printf " |%12s: | ok |\n" "$ARCH" >> $T_FILE + elif [ "$O" = "not" ] && [ -z "$K_GREP" ]; then + printf " |%12s: | ok |\n" "$ARCH" >> $T_FILE + else + S=$(grep -v "^#" "$F_FILE" | grep " $ARCH:") + if [ ! -z "$S" ]; then + echo "$S" >> $T_FILE + else + printf " |%12s: | TODO |\n" "$ARCH" \ + >> $T_FILE + fi + fi + done + echo " -----------------------" >> $T_FILE + mv $T_FILE $F_FILE +done diff --git a/Documentation/features/seccomp/seccomp-filter/arch-support.txt b/Documentation/features/seccomp/seccomp-filter/arch-support.txt index e4fad58a05e5..d4271b493b41 100644 --- a/Documentation/features/seccomp/seccomp-filter/arch-support.txt +++ b/Documentation/features/seccomp/seccomp-filter/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | - | parisc: | TODO | - | powerpc: | TODO | + | parisc: | ok | + | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | TODO | | sparc: | TODO | diff --git a/Documentation/features/time/arch-tick-broadcast/arch-support.txt b/Documentation/features/time/arch-tick-broadcast/arch-support.txt index 8052904b25fc..83d9e68462bb 100644 --- a/Documentation/features/time/arch-tick-broadcast/arch-support.txt +++ b/Documentation/features/time/arch-tick-broadcast/arch-support.txt @@ -17,12 +17,14 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | TODO | - | sh: | TODO | + | sh: | ok | | sparc: | TODO | | um: | TODO | | unicore32: | TODO | diff --git a/Documentation/features/time/clockevents/arch-support.txt b/Documentation/features/time/clockevents/arch-support.txt index 7c76b946297e..3d4908fce6da 100644 --- a/Documentation/features/time/clockevents/arch-support.txt +++ b/Documentation/features/time/clockevents/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | ok | | microblaze: | ok | | mips: | ok | + | nds32: | ok | | nios2: | ok | | openrisc: | ok | - | parisc: | TODO | + | parisc: | ok | | powerpc: | ok | + | riscv: | ok | | s390: | ok | | sh: | ok | | sparc: | ok | diff --git a/Documentation/features/time/context-tracking/arch-support.txt b/Documentation/features/time/context-tracking/arch-support.txt index 9433b3e523b3..c29974afffaa 100644 --- a/Documentation/features/time/context-tracking/arch-support.txt +++ b/Documentation/features/time/context-tracking/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | TODO | | sh: | TODO | | sparc: | ok | diff --git a/Documentation/features/time/irq-time-acct/arch-support.txt b/Documentation/features/time/irq-time-acct/arch-support.txt index 212dde0b578c..8d73c463ec27 100644 --- a/Documentation/features/time/irq-time-acct/arch-support.txt +++ b/Documentation/features/time/irq-time-acct/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | .. | - | powerpc: | .. | + | powerpc: | ok | + | riscv: | TODO | | s390: | .. | | sh: | TODO | | sparc: | .. | diff --git a/Documentation/features/time/modern-timekeeping/arch-support.txt b/Documentation/features/time/modern-timekeeping/arch-support.txt index 4074028f72f7..e7c6ea6b8fb3 100644 --- a/Documentation/features/time/modern-timekeeping/arch-support.txt +++ b/Documentation/features/time/modern-timekeeping/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | ok | | mips: | ok | + | nds32: | ok | | nios2: | ok | | openrisc: | ok | | parisc: | ok | | powerpc: | ok | + | riscv: | ok | | s390: | ok | | sh: | ok | | sparc: | ok | diff --git a/Documentation/features/time/virt-cpuacct/arch-support.txt b/Documentation/features/time/virt-cpuacct/arch-support.txt index a394d8820517..4646457461cf 100644 --- a/Documentation/features/time/virt-cpuacct/arch-support.txt +++ b/Documentation/features/time/virt-cpuacct/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | ok | | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | TODO | | sparc: | ok | diff --git a/Documentation/features/vm/ELF-ASLR/arch-support.txt b/Documentation/features/vm/ELF-ASLR/arch-support.txt index 082f93d5b40e..1f71d090ff2c 100644 --- a/Documentation/features/vm/ELF-ASLR/arch-support.txt +++ b/Documentation/features/vm/ELF-ASLR/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | ok | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | - | parisc: | TODO | + | parisc: | ok | | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | TODO | | sparc: | TODO | diff --git a/Documentation/features/vm/PG_uncached/arch-support.txt b/Documentation/features/vm/PG_uncached/arch-support.txt index 605e0abb756d..fbd5aa463b0a 100644 --- a/Documentation/features/vm/PG_uncached/arch-support.txt +++ b/Documentation/features/vm/PG_uncached/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | TODO | + | riscv: | TODO | | s390: | TODO | | sh: | TODO | | sparc: | TODO | diff --git a/Documentation/features/vm/THP/arch-support.txt b/Documentation/features/vm/THP/arch-support.txt index 7a8eb0bd5ca8..5d7ecc378f29 100644 --- a/Documentation/features/vm/THP/arch-support.txt +++ b/Documentation/features/vm/THP/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | .. | | microblaze: | .. | | mips: | ok | + | nds32: | TODO | | nios2: | .. | | openrisc: | .. | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | .. | | sparc: | ok | diff --git a/Documentation/features/vm/TLB/arch-support.txt b/Documentation/features/vm/TLB/arch-support.txt index 35fb99b2b3ea..f7af9678eb66 100644 --- a/Documentation/features/vm/TLB/arch-support.txt +++ b/Documentation/features/vm/TLB/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | .. | | microblaze: | .. | | mips: | TODO | + | nds32: | TODO | | nios2: | .. | | openrisc: | .. | | parisc: | TODO | | powerpc: | TODO | + | riscv: | TODO | | s390: | TODO | | sh: | TODO | | sparc: | TODO | diff --git a/Documentation/features/vm/huge-vmap/arch-support.txt b/Documentation/features/vm/huge-vmap/arch-support.txt index ed8b943ad8fc..d0713ccc7117 100644 --- a/Documentation/features/vm/huge-vmap/arch-support.txt +++ b/Documentation/features/vm/huge-vmap/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | TODO | + | riscv: | TODO | | s390: | TODO | | sh: | TODO | | sparc: | TODO | diff --git a/Documentation/features/vm/ioremap_prot/arch-support.txt b/Documentation/features/vm/ioremap_prot/arch-support.txt index 589947bdf0a8..8527601a3739 100644 --- a/Documentation/features/vm/ioremap_prot/arch-support.txt +++ b/Documentation/features/vm/ioremap_prot/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | TODO | | sh: | ok | | sparc: | TODO | diff --git a/Documentation/features/vm/numa-memblock/arch-support.txt b/Documentation/features/vm/numa-memblock/arch-support.txt index 8b8bea0318a0..1a988052cd24 100644 --- a/Documentation/features/vm/numa-memblock/arch-support.txt +++ b/Documentation/features/vm/numa-memblock/arch-support.txt @@ -9,7 +9,7 @@ | alpha: | TODO | | arc: | .. | | arm: | .. | - | arm64: | .. | + | arm64: | ok | | c6x: | .. | | h8300: | .. | | hexagon: | .. | @@ -17,10 +17,12 @@ | m68k: | .. | | microblaze: | ok | | mips: | ok | + | nds32: | TODO | | nios2: | .. | | openrisc: | .. | | parisc: | .. | | powerpc: | ok | + | riscv: | ok | | s390: | ok | | sh: | ok | | sparc: | ok | diff --git a/Documentation/features/vm/pte_special/arch-support.txt b/Documentation/features/vm/pte_special/arch-support.txt index 055004f467d2..6a608a6dcf71 100644 --- a/Documentation/features/vm/pte_special/arch-support.txt +++ b/Documentation/features/vm/pte_special/arch-support.txt @@ -17,10 +17,12 @@ | m68k: | TODO | | microblaze: | TODO | | mips: | TODO | + | nds32: | TODO | | nios2: | TODO | | openrisc: | TODO | | parisc: | TODO | | powerpc: | ok | + | riscv: | TODO | | s390: | ok | | sh: | ok | | sparc: | ok | diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 75d2d57e2c44..2c391338c675 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -69,31 +69,31 @@ prototypes: locking rules: all may block - i_mutex(inode) -lookup: yes -create: yes -link: yes (both) -mknod: yes -symlink: yes -mkdir: yes -unlink: yes (both) -rmdir: yes (both) (see below) -rename: yes (all) (see below) + i_rwsem(inode) +lookup: shared +create: exclusive +link: exclusive (both) +mknod: exclusive +symlink: exclusive +mkdir: exclusive +unlink: exclusive (both) +rmdir: exclusive (both)(see below) +rename: exclusive (all) (see below) readlink: no get_link: no -setattr: yes +setattr: exclusive permission: no (may not block if called in rcu-walk mode) get_acl: no getattr: no listxattr: no fiemap: no update_time: no -atomic_open: yes +atomic_open: exclusive tmpfile: no - Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on -victim. + Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_rwsem + exclusive on victim. cross-directory ->rename() has (per-superblock) ->s_vfs_rename_sem. See Documentation/filesystems/directory-locking for more detailed discussion @@ -111,10 +111,10 @@ prototypes: locking rules: all may block - i_mutex(inode) + i_rwsem(inode) list: no get: no -set: yes +set: exclusive --------------------------- super_operations --------------------------- prototypes: @@ -217,14 +217,14 @@ prototypes: locking rules: All except set_page_dirty and freepage may block - PageLocked(page) i_mutex + PageLocked(page) i_rwsem writepage: yes, unlocks (see below) readpage: yes, unlocks writepages: set_page_dirty no readpages: -write_begin: locks the page yes -write_end: yes, unlocks yes +write_begin: locks the page exclusive +write_end: yes, unlocks exclusive bmap: invalidatepage: yes releasepage: yes @@ -439,7 +439,10 @@ prototypes: ssize_t (*read_iter) (struct kiocb *, struct iov_iter *); ssize_t (*write_iter) (struct kiocb *, struct iov_iter *); int (*iterate) (struct file *, struct dir_context *); - unsigned int (*poll) (struct file *, struct poll_table_struct *); + int (*iterate_shared) (struct file *, struct dir_context *); + __poll_t (*poll) (struct file *, struct poll_table_struct *); + struct wait_queue_head * (*get_poll_head)(struct file *, __poll_t); + __poll_t (*poll_mask) (struct file *, __poll_t); long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long); long (*compat_ioctl) (struct file *, unsigned int, unsigned long); int (*mmap) (struct file *, struct vm_area_struct *); @@ -470,7 +473,7 @@ prototypes: }; locking rules: - All may block. + All except for ->poll_mask may block. ->llseek() locking has moved from llseek to the individual llseek implementations. If your fs is not using generic_file_llseek, you @@ -480,6 +483,10 @@ mutex or just to use i_size_read() instead. Note: this does not protect the file->f_pos against concurrent modifications since this is something the userspace has to take care about. +->iterate() is called with i_rwsem exclusive. + +->iterate_shared() is called with i_rwsem at least shared. + ->fasync() is responsible for maintaining the FASYNC bit in filp->f_flags. Most instances call fasync_helper(), which does that maintenance, so it's not normally something one needs to worry about. Return values > 0 will be @@ -498,6 +505,9 @@ in sys_read() and friends. the lease within the individual filesystem to record the result of the operation +->poll_mask can be called with or without the waitqueue lock for the waitqueue +returned from ->get_poll_head. + --------------------------- dquot_operations ------------------------------- prototypes: int (*write_dquot) (struct dquot *); diff --git a/Documentation/filesystems/afs.txt b/Documentation/filesystems/afs.txt index c5254f6d234d..8c6ea7b41048 100644 --- a/Documentation/filesystems/afs.txt +++ b/Documentation/filesystems/afs.txt @@ -11,7 +11,7 @@ Contents: - Proc filesystem. - The cell database. - Security. - - Examples. + - The @sys substitution. ======== @@ -230,3 +230,29 @@ If a file is opened with a particular key and then the file descriptor is passed to a process that doesn't have that key (perhaps over an AF_UNIX socket), then the operations on the file will be made with key that was used to open the file. + + +===================== +THE @SYS SUBSTITUTION +===================== + +The list of up to 16 @sys substitutions for the current network namespace can +be configured by writing a list to /proc/fs/afs/sysname: + + [root@andromeda ~]# echo foo amd64_linux_26 >/proc/fs/afs/sysname + +or cleared entirely by writing an empty list: + + [root@andromeda ~]# echo >/proc/fs/afs/sysname + +The current list for current network namespace can be retrieved by: + + [root@andromeda ~]# cat /proc/fs/afs/sysname + foo + amd64_linux_26 + +When @sys is being substituted for, each element of the list is tried in the +order given. + +By default, the list will contain one item that conforms to the pattern +"<arch>_linux_26", amd64 being the name for x86_64. diff --git a/Documentation/filesystems/caching/netfs-api.txt b/Documentation/filesystems/caching/netfs-api.txt index 0eb31de3a2c1..2a6f7399c1f3 100644 --- a/Documentation/filesystems/caching/netfs-api.txt +++ b/Documentation/filesystems/caching/netfs-api.txt @@ -129,20 +129,10 @@ To define an object, a structure of the following type should be filled out: const void *parent_netfs_data, const void *cookie_netfs_data); - uint16_t (*get_key)(const void *cookie_netfs_data, - void *buffer, - uint16_t bufmax); - - void (*get_attr)(const void *cookie_netfs_data, - uint64_t *size); - - uint16_t (*get_aux)(const void *cookie_netfs_data, - void *buffer, - uint16_t bufmax); - enum fscache_checkaux (*check_aux)(void *cookie_netfs_data, const void *data, - uint16_t datalen); + uint16_t datalen, + loff_t object_size); void (*get_context)(void *cookie_netfs_data, void *context); @@ -187,36 +177,7 @@ This has the following fields: cache in the parent's list will be chosen, or failing that, the first cache in the master list. - (4) A function to retrieve an object's key from the netfs [mandatory]. - - This function will be called with the netfs data that was passed to the - cookie acquisition function and the maximum length of key data that it may - provide. It should write the required key data into the given buffer and - return the quantity it wrote. - - (5) A function to retrieve attribute data from the netfs [optional]. - - This function will be called with the netfs data that was passed to the - cookie acquisition function. It should return the size of the file if - this is a data file. The size may be used to govern how much cache must - be reserved for this file in the cache. - - If the function is absent, a file size of 0 is assumed. - - (6) A function to retrieve auxiliary data from the netfs [optional]. - - This function will be called with the netfs data that was passed to the - cookie acquisition function and the maximum length of auxiliary data that - it may provide. It should write the auxiliary data into the given buffer - and return the quantity it wrote. - - If this function is absent, the auxiliary data length will be set to 0. - - The length of the auxiliary data buffer may be dependent on the key - length. A netfs mustn't rely on being able to provide more than 400 bytes - for both. - - (7) A function to check the auxiliary data [optional]. + (4) A function to check the auxiliary data [optional]. This function will be called to check that a match found in the cache for this object is valid. For instance with AFS it could check the auxiliary @@ -226,6 +187,9 @@ This has the following fields: If this function is absent, it will be assumed that matching objects in a cache are always valid. + The function is also passed the cache's idea of the object size and may + use this to manage coherency also. + If present, the function should return one of the following values: (*) FSCACHE_CHECKAUX_OKAY - the entry is okay as is @@ -235,7 +199,7 @@ This has the following fields: This function can also be used to extract data from the auxiliary data in the cache and copy it into the netfs's structures. - (8) A pair of functions to manage contexts for the completion callback + (5) A pair of functions to manage contexts for the completion callback [optional]. The cache read/write functions are passed a context which is then passed @@ -249,7 +213,7 @@ This has the following fields: required for indices as indices may not contain data. These functions may be called in interrupt context and so may not sleep. - (9) A function to mark a page as retaining cache metadata [optional]. + (6) A function to mark a page as retaining cache metadata [optional]. This is called by the cache to indicate that it is retaining in-memory information for this page and that the netfs should uncache the page when @@ -261,7 +225,7 @@ This has the following fields: This function is not required for indices as they're not permitted data. -(10) A function to unmark all the pages retaining cache metadata [mandatory]. + (7) A function to unmark all the pages retaining cache metadata [mandatory]. This is called by FS-Cache to indicate that a backing store is being unbound from a cookie and that all the marks on the pages should be @@ -333,12 +297,32 @@ the path to the file: struct fscache_cookie * fscache_acquire_cookie(struct fscache_cookie *parent, const struct fscache_object_def *def, + const void *index_key, + size_t index_key_len, + const void *aux_data, + size_t aux_data_len, void *netfs_data, + loff_t object_size, bool enable); This function creates an index entry in the index represented by parent, filling in the index entry by calling the operations pointed to by def. +A unique key that represents the object within the parent must be pointed to by +index_key and is of length index_key_len. + +An optional blob of auxiliary data that is to be stored within the cache can be +pointed to with aux_data and should be of length aux_data_len. This would +typically be used for storing coherency data. + +The netfs may pass an arbitrary value in netfs_data and this will be presented +to it in the event of any calling back. This may also be used in tracing or +logging of messages. + +The cache tracks the size of the data attached to an object and this set to be +object_size. For indices, this should be 0. This value will be passed to the +->check_aux() callback. + Note that this function never returns an error - all errors are handled internally. It may, however, return NULL to indicate no cookie. It is quite acceptable to pass this token back to this function as the parent to another @@ -355,30 +339,24 @@ must be enabled to do anything with it. A disabled cookie can be enabled by calling fscache_enable_cookie() (see below). For example, with AFS, a cell would be added to the primary index. This index -entry would have a dependent inode containing a volume location index for the -volume mappings within this cell: +entry would have a dependent inode containing volume mappings within this cell: cell->cache = fscache_acquire_cookie(afs_cache_netfs.primary_index, &afs_cell_cache_index_def, - cell, true); - -Then when a volume location was accessed, it would be entered into the cell's -index and an inode would be allocated that acts as a volume type and hash chain -combination: + cell->name, strlen(cell->name), + NULL, 0, + cell, 0, true); - vlocation->cache = - fscache_acquire_cookie(cell->cache, - &afs_vlocation_cache_index_def, - vlocation, true); - -And then a particular flavour of volume (R/O for example) could be added to -that index, creating another index for vnodes (AFS inode equivalents): +And then a particular volume could be added to that index by ID, creating +another index for vnodes (AFS inode equivalents): volume->cache = - fscache_acquire_cookie(vlocation->cache, + fscache_acquire_cookie(volume->cell->cache, &afs_volume_cache_index_def, - volume, true); + &volume->vid, sizeof(volume->vid), + NULL, 0, + volume, 0, true); ====================== @@ -392,7 +370,9 @@ the object definition should be something other than index type. vnode->cache = fscache_acquire_cookie(volume->cache, &afs_vnode_cache_object_def, - vnode, true); + &key, sizeof(key), + &aux, sizeof(aux), + vnode, vnode->status.size, true); ================================= @@ -408,7 +388,9 @@ it would be some other type of object such as a data file. xattr->cache = fscache_acquire_cookie(vnode->cache, &afs_xattr_cache_object_def, - xattr, true); + &xattr->name, strlen(xattr->name), + NULL, 0, + xattr, strlen(xattr->val), true); Miscellaneous objects might be used to store extended attributes or directory entries for example. @@ -425,8 +407,7 @@ cache to adjust its metadata for data tracking appropriately: int fscache_attr_changed(struct fscache_cookie *cookie); The cache will return -ENOBUFS if there is no backing cache or if there is no -space to allocate any extra metadata required in the cache. The attributes -will be accessed with the get_attr() cookie definition operation. +space to allocate any extra metadata required in the cache. Note that attempts to read or write data pages in the cache over this size may be rebuffed with -ENOBUFS. @@ -551,12 +532,13 @@ written back to the cache: int fscache_write_page(struct fscache_cookie *cookie, struct page *page, + loff_t object_size, gfp_t gfp); The cookie argument must specify a data file cookie, the page specified should contain the data to be written (and is also used to specify the page number), -and the gfp argument is used to control how any memory allocations made are -satisfied. +object_size is the revised size of the object and the gfp argument is used to +control how any memory allocations made are satisfied. The page must have first been read or allocated successfully and must not have been uncached before writing is performed. @@ -717,21 +699,23 @@ INDEX AND DATA FILE CONSISTENCY To find out whether auxiliary data for an object is up to data within the cache, the following function can be called: - int fscache_check_consistency(struct fscache_cookie *cookie) + int fscache_check_consistency(struct fscache_cookie *cookie, + const void *aux_data); This will call back to the netfs to check whether the auxiliary data associated -with a cookie is correct. It returns 0 if it is and -ESTALE if it isn't; it -may also return -ENOMEM and -ERESTARTSYS. +with a cookie is correct; if aux_data is non-NULL, it will update the auxiliary +data buffer first. It returns 0 if it is and -ESTALE if it isn't; it may also +return -ENOMEM and -ERESTARTSYS. To request an update of the index data for an index or other object, the following function should be called: - void fscache_update_cookie(struct fscache_cookie *cookie); + void fscache_update_cookie(struct fscache_cookie *cookie, + const void *aux_data); -This function will refer back to the netfs_data pointer stored in the cookie by -the acquisition function to obtain the data to write into each revised index -entry. The update method in the parent index definition will be called to -transfer the data. +This function will update the cookie's auxiliary data buffer from aux_data if +that is non-NULL and then schedule this to be stored on disk. The update +method in the parent index definition will be called to transfer the data. Note that partial updates may happen automatically at other times, such as when data blocks are added to a data file object. @@ -748,10 +732,11 @@ still possible to uncache pages and relinquish the cookie. The initial enablement state is set by fscache_acquire_cookie(), but the cookie can be enabled or disabled later. To disable a cookie, call: - + void fscache_disable_cookie(struct fscache_cookie *cookie, + const void *aux_data, bool invalidate); - + If the cookie is not already disabled, this locks the cookie against other enable and disable ops, marks the cookie as being disabled, discards or invalidates any backing objects and waits for cessation of activity on any @@ -760,13 +745,15 @@ associated object before unlocking the cookie. All possible failures are handled internally. The caller should consider calling fscache_uncache_all_inode_pages() afterwards to make sure all page markings are cleared up. - + Cookies can be enabled or reenabled with: - + void fscache_enable_cookie(struct fscache_cookie *cookie, + const void *aux_data, + loff_t object_size, bool (*can_enable)(void *data), void *data) - + If the cookie is not already enabled, this locks the cookie against other enable and disable ops, invokes can_enable() and, if the cookie is not an index cookie, will begin the procedure of acquiring backing objects. @@ -777,6 +764,12 @@ ruling as to whether or not enablement should actually be permitted to begin. All possible failures are handled internally. The cookie will only be marked as enabled if provisional backing objects are allocated. +The object's data size is updated from object_size and is passed to the +->check_aux() function. + +In both cases, the cookie's auxiliary data buffer is updated from aux_data if +that is non-NULL inside the enablement lock before proceeding. + =============================== MISCELLANEOUS COOKIE OPERATIONS @@ -823,6 +816,7 @@ COOKIE UNREGISTRATION To get rid of a cookie, this function should be called. void fscache_relinquish_cookie(struct fscache_cookie *cookie, + const void *aux_data, bool retire); If retire is non-zero, then the object will be marked for recycling, and all @@ -833,6 +827,9 @@ If retire is zero, then the object may be available again when next the acquisition function is called. Retirement here will overrule the pinning on a cookie. +The cookie's auxiliary data will be updated from aux_data if that is non-NULL +so that the cache can lazily update it on disk. + One very important note - relinquish must NOT be called for a cookie unless all the cookies for "child" indices, objects and pages have been relinquished first. diff --git a/Documentation/filesystems/ceph.txt b/Documentation/filesystems/ceph.txt index 0b302a11718a..d7f011ddc150 100644 --- a/Documentation/filesystems/ceph.txt +++ b/Documentation/filesystems/ceph.txt @@ -62,6 +62,18 @@ subdirectories, and a summation of all nested file sizes. This makes the identification of large disk space consumers relatively quick, as no 'du' or similar recursive scan of the file system is required. +Finally, Ceph also allows quotas to be set on any directory in the system. +The quota can restrict the number of bytes or the number of files stored +beneath that point in the directory hierarchy. Quotas can be set using +extended attributes 'ceph.quota.max_files' and 'ceph.quota.max_bytes', eg: + + setfattr -n ceph.quota.max_bytes -v 100000000 /some/dir + getfattr -n ceph.quota.max_bytes /some/dir + +A limitation of the current quotas implementation is that it relies on the +cooperation of the client mounting the file system to stop writers when a +limit is reached. A modified or adversarial client cannot be prevented +from writing as much data as it needs. Mount Syntax ============ @@ -137,6 +149,10 @@ Mount Options noasyncreaddir Do not use the dcache as above for readdir. + noquotadf + Report overall filesystem usage in statfs instead of using the root + directory quota. + More Information ================ diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst index cfbc18f0d9c9..48b424de85bb 100644 --- a/Documentation/filesystems/fscrypt.rst +++ b/Documentation/filesystems/fscrypt.rst @@ -191,11 +191,21 @@ Currently, the following pairs of encryption modes are supported: - AES-256-XTS for contents and AES-256-CTS-CBC for filenames - AES-128-CBC for contents and AES-128-CTS-CBC for filenames +- Speck128/256-XTS for contents and Speck128/256-CTS-CBC for filenames It is strongly recommended to use AES-256-XTS for contents encryption. AES-128-CBC was added only for low-powered embedded devices with crypto accelerators such as CAAM or CESA that do not support XTS. +Similarly, Speck128/256 support was only added for older or low-end +CPUs which cannot do AES fast enough -- especially ARM CPUs which have +NEON instructions but not the Cryptography Extensions -- and for which +it would not otherwise be feasible to use encryption at all. It is +not recommended to use Speck on CPUs that have AES instructions. +Speck support is only available if it has been enabled in the crypto +API via CONFIG_CRYPTO_SPECK. Also, on ARM platforms, to get +acceptable performance CONFIG_CRYPTO_SPECK_NEON must be enabled. + New encryption modes can be added relatively easily, without changes to individual filesystems. However, authenticated encryption (AE) modes are not currently supported because of the difficulty of dealing diff --git a/Documentation/filesystems/gfs2-glocks.txt b/Documentation/filesystems/gfs2-glocks.txt index 1fb12f9dfe48..7059623635b2 100644 --- a/Documentation/filesystems/gfs2-glocks.txt +++ b/Documentation/filesystems/gfs2-glocks.txt @@ -100,14 +100,15 @@ indicates that it is caching uptodate data. Glock locking order within GFS2: - 1. i_mutex (if required) + 1. i_rwsem (if required) 2. Rename glock (for rename only) 3. Inode glock(s) (Parents before children, inodes at "same level" with same parent in lock number order) 4. Rgrp glock(s) (for (de)allocation operations) 5. Transaction glock (via gfs2_trans_begin) for non-read operations - 6. Page lock (always last, very important!) + 6. i_rw_mutex (if required) + 7. Page lock (always last, very important!) There are two glocks per inode. One deals with access to the inode itself (locking order as above), and the other, known as the iopen diff --git a/Documentation/filesystems/orangefs.txt b/Documentation/filesystems/orangefs.txt index e2818b60a5c2..f4ba94950e3f 100644 --- a/Documentation/filesystems/orangefs.txt +++ b/Documentation/filesystems/orangefs.txt @@ -21,10 +21,16 @@ Orangefs features include: * Stateless -MAILING LIST -============ +MAILING LIST ARCHIVES +===================== -http://beowulf-underground.org/mailman/listinfo/pvfs2-users +http://lists.orangefs.org/pipermail/devel_lists.orangefs.org/ + + +MAILING LIST SUBMISSIONS +======================== + +devel@lists.orangefs.org DOCUMENTATION @@ -42,12 +48,59 @@ Orangefs versions prior to 2.9.3 would not be compatible with the upstream version of the kernel client. -BUILDING THE USERSPACE FILESYSTEM ON A SINGLE SERVER -==================================================== +RUNNING ORANGEFS ON A SINGLE SERVER +=================================== + +OrangeFS is usually run in large installations with multiple servers and +clients, but a complete filesystem can be run on a single machine for +development and testing. + +On Fedora, install orangefs and orangefs-server. + +dnf -y install orangefs orangefs-server + +There is an example server configuration file in +/etc/orangefs/orangefs.conf. Change localhost to your hostname if +necessary. + +To generate a filesystem to run xfstests against, see below. + +There is an example client configuration file in /etc/pvfs2tab. It is a +single line. Uncomment it and change the hostname if necessary. This +controls clients which use libpvfs2. This does not control the +pvfs2-client-core. + +Create the filesystem. + +pvfs2-server -f /etc/orangefs/orangefs.conf + +Start the server. + +systemctl start orangefs-server + +Test the server. + +pvfs2-ping -m /pvfsmnt + +Start the client. The module must be compiled in or loaded before this +point. + +systemctl start orangefs-client + +Mount the filesystem. + +mount -t pvfs2 tcp://localhost:3334/orangefs /pvfsmnt + -You can omit --prefix if you don't care that things are sprinkled around in -/usr/local. As of version 2.9.6, Orangefs uses Berkeley DB by default, we -will probably be changing the default to lmdb soon. +BUILDING ORANGEFS ON A SINGLE SERVER +==================================== + +Where OrangeFS cannot be installed from distribution packages, it may be +built from source. + +You can omit --prefix if you don't care that things are sprinkled around +in /usr/local. As of version 2.9.6, OrangeFS uses Berkeley DB by +default, we will probably be changing the default to LMDB soon. ./configure --prefix=/opt/ofs --with-db-backend=lmdb @@ -55,35 +108,69 @@ make make install -Create an orangefs config file: +Create an orangefs config file. + /opt/ofs/bin/pvfs2-genconfig /etc/pvfs2.conf - for "Enter hostnames", use the hostname, don't let it default to - localhost. +Create an /etc/pvfs2tab file. + +echo tcp://localhost:3334/orangefs /pvfsmnt pvfs2 defaults,noauto 0 0 > \ + /etc/pvfs2tab + +Create the mount point you specified in the tab file if needed. -create a pvfs2tab file in /etc: -cat /etc/pvfs2tab -tcp://myhostname:3334/orangefs /mymountpoint pvfs2 defaults,noauto 0 0 +mkdir /pvfsmnt -create the mount point you specified in the tab file if needed: -mkdir /mymountpoint +Bootstrap the server. -bootstrap the server: -/opt/ofs/sbin/pvfs2-server /etc/pvfs2.conf -f +/opt/ofs/sbin/pvfs2-server -f /etc/pvfs2.conf + +Start the server. -start the server: /opt/osf/sbin/pvfs2-server /etc/pvfs2.conf -Now the server is running. At this point you might like to -prove things are working with: +Now the server should be running. Pvfs2-ls is a simple +test to verify that the server is running. + +/opt/ofs/bin/pvfs2-ls /pvfsmnt -/opt/osf/bin/pvfs2-ls /mymountpoint +If stuff seems to be working, load the kernel module and +turn on the client core. -If stuff seems to be working, turn on the client core: -/opt/osf/sbin/pvfs2-client -p /opt/osf/sbin/pvfs2-client-core +/opt/ofs/sbin/pvfs2-client -p /opt/osf/sbin/pvfs2-client-core Mount your filesystem. -mount -t pvfs2 tcp://myhostname:3334/orangefs /mymountpoint + +mount -t pvfs2 tcp://localhost:3334/orangefs /pvfsmnt + + +RUNNING XFSTESTS +================ + +It is useful to use a scratch filesystem with xfstests. This can be +done with only one server. + +Make a second copy of the FileSystem section in the server configuration +file, which is /etc/orangefs/orangefs.conf. Change the Name to scratch. +Change the ID to something other than the ID of the first FileSystem +section (2 is usually a good choice). + +Then there are two FileSystem sections: orangefs and scratch. + +This change should be made before creating the filesystem. + +pvfs2-server -f /etc/orangefs/orangefs.conf + +To run xfstests, create /etc/xfsqa.config. + +TEST_DIR=/orangefs +TEST_DEV=tcp://localhost:3334/orangefs +SCRATCH_MNT=/scratch +SCRATCH_DEV=tcp://localhost:3334/scratch + +Then xfstests can be run + +./check -pvfs2 OPTIONS diff --git a/Documentation/filesystems/overlayfs.txt b/Documentation/filesystems/overlayfs.txt index 6ea1e64d1464..961b287ef323 100644 --- a/Documentation/filesystems/overlayfs.txt +++ b/Documentation/filesystems/overlayfs.txt @@ -14,9 +14,13 @@ The result will inevitably fail to look exactly like a normal filesystem for various technical reasons. The expectation is that many use cases will be able to ignore these differences. -This approach is 'hybrid' because the objects that appear in the -filesystem do not all appear to belong to that filesystem. In many -cases an object accessed in the union will be indistinguishable + +Overlay objects +--------------- + +The overlay filesystem approach is 'hybrid', because the objects that +appear in the filesystem do not always appear to belong to that filesystem. +In many cases, an object accessed in the union will be indistinguishable from accessing the corresponding object from the original filesystem. This is most obvious from the 'st_dev' field returned by stat(2). @@ -34,6 +38,19 @@ make the overlay mount more compliant with filesystem scanners and overlay objects will be distinguishable from the corresponding objects in the original filesystem. +On 64bit systems, even if all overlay layers are not on the same +underlying filesystem, the same compliant behavior could be achieved +with the "xino" feature. The "xino" feature composes a unique object +identifier from the real object st_ino and an underlying fsid index. +If all underlying filesystems support NFS file handles and export file +handles with 32bit inode number encoding (e.g. ext4), overlay filesystem +will use the high inode number bits for fsid. Even when the underlying +filesystem uses 64bit inode numbers, users can still enable the "xino" +feature with the "-o xino=on" overlay mount option. That is useful for the +case of underlying filesystems like xfs and tmpfs, which use 64bit inode +numbers, but are very unlikely to use the high inode number bit. + + Upper and Lower --------------- @@ -290,10 +307,19 @@ Non-standard behavior --------------------- The copy_up operation essentially creates a new, identical file and -moves it over to the old name. The new file may be on a different -filesystem, so both st_dev and st_ino of the file may change. +moves it over to the old name. Any open files referring to this inode +will access the old data. + +The new file may be on a different filesystem, so both st_dev and st_ino +of the real file may change. The values of st_dev and st_ino returned by +stat(2) on an overlay object are often not the same as the real file +stat(2) values to prevent the values from changing on copy_up. -Any open files referring to this inode will access the old data. +Unless "xino" feature is enabled, when overlay layers are not all on the +same underlying filesystem, the value of st_dev may be different for two +non-directory objects in the same overlay filesystem and the value of +st_ino for directory objects may be non persistent and could change even +while the overlay filesystem is still mounted. Unless "inode index" feature is enabled, if a file with multiple hard links is copied up, then this will "break" the link. Changes will not be @@ -302,6 +328,7 @@ propagated to other names referring to the same inode. Unless "redirect_dir" feature is enabled, rename(2) on a lower or merged directory will fail with EXDEV. + Changes to underlying filesystems --------------------------------- diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 2a84bb334894..520f6a84cf50 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -515,7 +515,8 @@ guarantees: The /proc/PID/clear_refs is used to reset the PG_Referenced and ACCESSED/YOUNG bits on both physical and virtual pages associated with a process, and the -soft-dirty bit on pte (see Documentation/vm/soft-dirty.txt for details). +soft-dirty bit on pte (see Documentation/admin-guide/mm/soft-dirty.rst +for details). To clear the bits for all the pages associated with the process > echo 1 > /proc/PID/clear_refs @@ -536,7 +537,8 @@ Any other value written to /proc/PID/clear_refs will have no effect. The /proc/pid/pagemap gives the PFN, which can be used to find the pageflags using /proc/kpageflags and number of times a page is mapped using -/proc/kpagecount. For detailed explanation, see Documentation/vm/pagemap.txt. +/proc/kpagecount. For detailed explanation, see +Documentation/admin-guide/mm/pagemap.rst. The /proc/pid/numa_maps is an extension based on maps, showing the memory locality and binding policy, as well as the memory usage (in pages) of @@ -564,7 +566,7 @@ address policy mapping details Where: "address" is the starting address for the mapping; -"policy" reports the NUMA memory policy set for the mapping (see vm/numa_memory_policy.txt); +"policy" reports the NUMA memory policy set for the mapping (see Documentation/admin-guide/mm/numa_memory_policy.rst); "mapping details" summarizes mapping data such as mapping type, page usage counters, node locality page counters (N0 == node0, N1 == node1, ...) and the kernel page size, in KB, that is backing the mapping up. diff --git a/Documentation/filesystems/tmpfs.txt b/Documentation/filesystems/tmpfs.txt index a85355cf85f4..d06e9a59a9f4 100644 --- a/Documentation/filesystems/tmpfs.txt +++ b/Documentation/filesystems/tmpfs.txt @@ -105,8 +105,9 @@ policy for the file will revert to "default" policy. NUMA memory allocation policies have optional flags that can be used in conjunction with their modes. These optional flags can be specified when tmpfs is mounted by appending them to the mode before the NodeList. -See Documentation/vm/numa_memory_policy.txt for a list of all available -memory allocation policy mode flags and their effect on memory policy. +See Documentation/admin-guide/mm/numa_memory_policy.rst for a list of +all available memory allocation policy mode flags and their effect on +memory policy. =static is equivalent to MPOL_F_STATIC_NODES =relative is equivalent to MPOL_F_RELATIVE_NODES diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index 5fd325df59e2..829a7b7857a4 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -856,7 +856,9 @@ struct file_operations { ssize_t (*read_iter) (struct kiocb *, struct iov_iter *); ssize_t (*write_iter) (struct kiocb *, struct iov_iter *); int (*iterate) (struct file *, struct dir_context *); - unsigned int (*poll) (struct file *, struct poll_table_struct *); + __poll_t (*poll) (struct file *, struct poll_table_struct *); + struct wait_queue_head * (*get_poll_head)(struct file *, __poll_t); + __poll_t (*poll_mask) (struct file *, __poll_t); long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long); long (*compat_ioctl) (struct file *, unsigned int, unsigned long); int (*mmap) (struct file *, struct vm_area_struct *); @@ -901,6 +903,17 @@ otherwise noted. activity on this file and (optionally) go to sleep until there is activity. Called by the select(2) and poll(2) system calls + get_poll_head: Returns the struct wait_queue_head that callers can + wait on. Callers need to check the returned events using ->poll_mask + once woken. Can return NULL to indicate polling is not supported, + or any error code using the ERR_PTR convention to indicate that a + grave error occured and ->poll_mask shall not be called. + + poll_mask: return the mask of EPOLL* values describing the file descriptor + state. Called either before going to sleep on the waitqueue returned by + get_poll_head, or after it has been woken. If ->get_poll_head and + ->poll_mask are implemented ->poll does not need to be implement. + unlocked_ioctl: called by the ioctl(2) system call. compat_ioctl: called by the ioctl(2) system call when 32 bit system calls diff --git a/Documentation/fpga/fpga-mgr.txt b/Documentation/fpga/fpga-mgr.txt deleted file mode 100644 index cc6413ed6fc9..000000000000 --- a/Documentation/fpga/fpga-mgr.txt +++ /dev/null @@ -1,199 +0,0 @@ -FPGA Manager Core - -Alan Tull 2015 - -Overview -======== - -The FPGA manager core exports a set of functions for programming an FPGA with -an image. The API is manufacturer agnostic. All manufacturer specifics are -hidden away in a low level driver which registers a set of ops with the core. -The FPGA image data itself is very manufacturer specific, but for our purposes -it's just binary data. The FPGA manager core won't parse it. - -The FPGA image to be programmed can be in a scatter gather list, a single -contiguous buffer, or a firmware file. Because allocating contiguous kernel -memory for the buffer should be avoided, users are encouraged to use a scatter -gather list instead if possible. - -The particulars for programming the image are presented in a structure (struct -fpga_image_info). This struct contains parameters such as pointers to the -FPGA image as well as image-specific particulars such as whether the image was -built for full or partial reconfiguration. - -API Functions: -============== - -To program the FPGA: --------------------- - - int fpga_mgr_load(struct fpga_manager *mgr, - struct fpga_image_info *info); - -Load the FPGA from an image which is indicated in the info. If successful, -the FPGA ends up in operating mode. Return 0 on success or a negative error -code. - -To allocate or free a struct fpga_image_info: ---------------------------------------------- - - struct fpga_image_info *fpga_image_info_alloc(struct device *dev); - - void fpga_image_info_free(struct fpga_image_info *info); - -To get/put a reference to a FPGA manager: ------------------------------------------ - - struct fpga_manager *of_fpga_mgr_get(struct device_node *node); - struct fpga_manager *fpga_mgr_get(struct device *dev); - void fpga_mgr_put(struct fpga_manager *mgr); - -Given a DT node or device, get a reference to a FPGA manager. This pointer -can be saved until you are ready to program the FPGA. fpga_mgr_put releases -the reference. - - -To get exclusive control of a FPGA manager: -------------------------------------------- - - int fpga_mgr_lock(struct fpga_manager *mgr); - void fpga_mgr_unlock(struct fpga_manager *mgr); - -The user should call fpga_mgr_lock and verify that it returns 0 before -attempting to program the FPGA. Likewise, the user should call -fpga_mgr_unlock when done programming the FPGA. - - -To register or unregister the low level FPGA-specific driver: -------------------------------------------------------------- - - int fpga_mgr_register(struct device *dev, const char *name, - const struct fpga_manager_ops *mops, - void *priv); - - void fpga_mgr_unregister(struct device *dev); - -Use of these two functions is described below in "How To Support a new FPGA -device." - - -How to write an image buffer to a supported FPGA -================================================ -#include <linux/fpga/fpga-mgr.h> - -struct fpga_manager *mgr; -struct fpga_image_info *info; -int ret; - -/* - * Get a reference to FPGA manager. The manager is not locked, so you can - * hold onto this reference without it preventing programming. - * - * This example uses the device node of the manager. Alternatively, use - * fpga_mgr_get(dev) instead if you have the device. - */ -mgr = of_fpga_mgr_get(mgr_node); - -/* struct with information about the FPGA image to program. */ -info = fpga_image_info_alloc(dev); - -/* flags indicates whether to do full or partial reconfiguration */ -info->flags = FPGA_MGR_PARTIAL_RECONFIG; - -/* - * At this point, indicate where the image is. This is pseudo-code; you're - * going to use one of these three. - */ -if (image is in a scatter gather table) { - - info->sgt = [your scatter gather table] - -} else if (image is in a buffer) { - - info->buf = [your image buffer] - info->count = [image buffer size] - -} else if (image is in a firmware file) { - - info->firmware_name = devm_kstrdup(dev, firmware_name, GFP_KERNEL); - -} - -/* Get exclusive control of FPGA manager */ -ret = fpga_mgr_lock(mgr); - -/* Load the buffer to the FPGA */ -ret = fpga_mgr_buf_load(mgr, &info, buf, count); - -/* Release the FPGA manager */ -fpga_mgr_unlock(mgr); -fpga_mgr_put(mgr); - -/* Deallocate the image info if you're done with it */ -fpga_image_info_free(info); - -How to support a new FPGA device -================================ -To add another FPGA manager, write a driver that implements a set of ops. The -probe function calls fpga_mgr_register(), such as: - -static const struct fpga_manager_ops socfpga_fpga_ops = { - .write_init = socfpga_fpga_ops_configure_init, - .write = socfpga_fpga_ops_configure_write, - .write_complete = socfpga_fpga_ops_configure_complete, - .state = socfpga_fpga_ops_state, -}; - -static int socfpga_fpga_probe(struct platform_device *pdev) -{ - struct device *dev = &pdev->dev; - struct socfpga_fpga_priv *priv; - int ret; - - priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); - if (!priv) - return -ENOMEM; - - /* ... do ioremaps, get interrupts, etc. and save - them in priv... */ - - return fpga_mgr_register(dev, "Altera SOCFPGA FPGA Manager", - &socfpga_fpga_ops, priv); -} - -static int socfpga_fpga_remove(struct platform_device *pdev) -{ - fpga_mgr_unregister(&pdev->dev); - - return 0; -} - - -The ops will implement whatever device specific register writes are needed to -do the programming sequence for this particular FPGA. These ops return 0 for -success or negative error codes otherwise. - -The programming sequence is: - 1. .write_init - 2. .write or .write_sg (may be called once or multiple times) - 3. .write_complete - -The .write_init function will prepare the FPGA to receive the image data. The -buffer passed into .write_init will be atmost .initial_header_size bytes long, -if the whole bitstream is not immediately available then the core code will -buffer up at least this much before starting. - -The .write function writes a buffer to the FPGA. The buffer may be contain the -whole FPGA image or may be a smaller chunk of an FPGA image. In the latter -case, this function is called multiple times for successive chunks. This interface -is suitable for drivers which use PIO. - -The .write_sg version behaves the same as .write except the input is a sg_table -scatter list. This interface is suitable for drivers which use DMA. - -The .write_complete function is called after all the image has been written -to put the FPGA into operating mode. - -The ops include a .state function which will read the hardware FPGA manager and -return a code of type enum fpga_mgr_states. It doesn't result in a change in -hardware state. diff --git a/Documentation/fpga/fpga-region.txt b/Documentation/fpga/fpga-region.txt deleted file mode 100644 index 139a02ba1ff6..000000000000 --- a/Documentation/fpga/fpga-region.txt +++ /dev/null @@ -1,95 +0,0 @@ -FPGA Regions - -Alan Tull 2017 - -CONTENTS - - Introduction - - The FPGA region API - - Usage example - -Introduction -============ - -This document is meant to be an brief overview of the FPGA region API usage. A -more conceptual look at regions can be found in [1]. - -For the purposes of this API document, let's just say that a region associates -an FPGA Manager and a bridge (or bridges) with a reprogrammable region of an -FPGA or the whole FPGA. The API provides a way to register a region and to -program a region. - -Currently the only layer above fpga-region.c in the kernel is the Device Tree -support (of-fpga-region.c) described in [1]. The DT support layer uses regions -to program the FPGA and then DT to handle enumeration. The common region code -is intended to be used by other schemes that have other ways of accomplishing -enumeration after programming. - -An fpga-region can be set up to know the following things: -* which FPGA manager to use to do the programming -* which bridges to disable before programming and enable afterwards. - -Additional info needed to program the FPGA image is passed in the struct -fpga_image_info [2] including: -* pointers to the image as either a scatter-gather buffer, a contiguous - buffer, or the name of firmware file -* flags indicating specifics such as whether the image if for partial - reconfiguration. - -=================== -The FPGA region API -=================== - -To register or unregister a region: ------------------------------------ - - int fpga_region_register(struct device *dev, - struct fpga_region *region); - int fpga_region_unregister(struct fpga_region *region); - -An example of usage can be seen in the probe function of [3] - -To program an FPGA: -------------------- - int fpga_region_program_fpga(struct fpga_region *region); - -This function operates on info passed in the fpga_image_info -(region->info). - -This function will attempt to: - * lock the region's mutex - * lock the region's FPGA manager - * build a list of FPGA bridges if a method has been specified to do so - * disable the bridges - * program the FPGA - * re-enable the bridges - * release the locks - -============= -Usage example -============= - -First, allocate the info struct: - - info = fpga_image_info_alloc(dev); - if (!info) - return -ENOMEM; - -Set flags as needed, i.e. - - info->flags |= FPGA_MGR_PARTIAL_RECONFIG; - -Point to your FPGA image, such as: - - info->sgt = &sgt; - -Add info to region and do the programming: - - region->info = info; - ret = fpga_region_program_fpga(region); - -Then enumerate whatever hardware has appeared in the FPGA. - --- -[1] ../devicetree/bindings/fpga/fpga-region.txt -[2] ./fpga-mgr.txt -[3] ../../drivers/fpga/of-fpga-region.c diff --git a/Documentation/fpga/overview.txt b/Documentation/fpga/overview.txt deleted file mode 100644 index 0f1236e7e675..000000000000 --- a/Documentation/fpga/overview.txt +++ /dev/null @@ -1,23 +0,0 @@ -Linux kernel FPGA support - -Alan Tull 2017 - -The main point of this project has been to separate the out the upper layers -that know when to reprogram a FPGA from the lower layers that know how to -reprogram a specific FPGA device. The intention is to make this manufacturer -agnostic, understanding that of course the FPGA images are very device specific -themselves. - -The framework in the kernel includes: -* low level FPGA manager drivers that know how to program a specific device -* the fpga-mgr framework they are registered with -* low level FPGA bridge drivers for hard/soft bridges which are intended to - be disable during FPGA programming -* the fpga-bridge framework they are registered with -* the fpga-region framework which associates and controls managers and bridges - as reconfigurable regions -* the of-fpga-region support for reprogramming FPGAs when device tree overlays - are applied. - -I would encourage you the user to add code that creates FPGA regions rather -that trying to control managers and bridges separately. diff --git a/Documentation/gpu/drivers.rst b/Documentation/gpu/drivers.rst index e8c84419a2a1..f982558fc25d 100644 --- a/Documentation/gpu/drivers.rst +++ b/Documentation/gpu/drivers.rst @@ -10,8 +10,10 @@ GPU Driver Documentation tegra tinydrm tve200 + v3d vc4 bridge/dw-hdmi + xen-front .. only:: subproject and html diff --git a/Documentation/gpu/i915.rst b/Documentation/gpu/i915.rst index 41dc881b00dc..055df45596c1 100644 --- a/Documentation/gpu/i915.rst +++ b/Documentation/gpu/i915.rst @@ -58,6 +58,12 @@ Intel GVT-g Host Support(vGPU device model) .. kernel-doc:: drivers/gpu/drm/i915/intel_gvt.c :internal: +Workarounds +----------- + +.. kernel-doc:: drivers/gpu/drm/i915/intel_workarounds.c + :doc: Hardware workarounds + Display Hardware Handling ========================= @@ -249,6 +255,103 @@ Memory Management and Command Submission This sections covers all things related to the GEM implementation in the i915 driver. +Intel GPU Basics +---------------- + +An Intel GPU has multiple engines. There are several engine types. + +- RCS engine is for rendering 3D and performing compute, this is named + `I915_EXEC_RENDER` in user space. +- BCS is a blitting (copy) engine, this is named `I915_EXEC_BLT` in user + space. +- VCS is a video encode and decode engine, this is named `I915_EXEC_BSD` + in user space +- VECS is video enhancement engine, this is named `I915_EXEC_VEBOX` in user + space. +- The enumeration `I915_EXEC_DEFAULT` does not refer to specific engine; + instead it is to be used by user space to specify a default rendering + engine (for 3D) that may or may not be the same as RCS. + +The Intel GPU family is a family of integrated GPU's using Unified +Memory Access. For having the GPU "do work", user space will feed the +GPU batch buffers via one of the ioctls `DRM_IOCTL_I915_GEM_EXECBUFFER2` +or `DRM_IOCTL_I915_GEM_EXECBUFFER2_WR`. Most such batchbuffers will +instruct the GPU to perform work (for example rendering) and that work +needs memory from which to read and memory to which to write. All memory +is encapsulated within GEM buffer objects (usually created with the ioctl +`DRM_IOCTL_I915_GEM_CREATE`). An ioctl providing a batchbuffer for the GPU +to create will also list all GEM buffer objects that the batchbuffer reads +and/or writes. For implementation details of memory management see +`GEM BO Management Implementation Details`_. + +The i915 driver allows user space to create a context via the ioctl +`DRM_IOCTL_I915_GEM_CONTEXT_CREATE` which is identified by a 32-bit +integer. Such a context should be viewed by user-space as -loosely- +analogous to the idea of a CPU process of an operating system. The i915 +driver guarantees that commands issued to a fixed context are to be +executed so that writes of a previously issued command are seen by +reads of following commands. Actions issued between different contexts +(even if from the same file descriptor) are NOT given that guarantee +and the only way to synchronize across contexts (even from the same +file descriptor) is through the use of fences. At least as far back as +Gen4, also have that a context carries with it a GPU HW context; +the HW context is essentially (most of atleast) the state of a GPU. +In addition to the ordering guarantees, the kernel will restore GPU +state via HW context when commands are issued to a context, this saves +user space the need to restore (most of atleast) the GPU state at the +start of each batchbuffer. The non-deprecated ioctls to submit batchbuffer +work can pass that ID (in the lower bits of drm_i915_gem_execbuffer2::rsvd1) +to identify what context to use with the command. + +The GPU has its own memory management and address space. The kernel +driver maintains the memory translation table for the GPU. For older +GPUs (i.e. those before Gen8), there is a single global such translation +table, a global Graphics Translation Table (GTT). For newer generation +GPUs each context has its own translation table, called Per-Process +Graphics Translation Table (PPGTT). Of important note, is that although +PPGTT is named per-process it is actually per context. When user space +submits a batchbuffer, the kernel walks the list of GEM buffer objects +used by the batchbuffer and guarantees that not only is the memory of +each such GEM buffer object resident but it is also present in the +(PP)GTT. If the GEM buffer object is not yet placed in the (PP)GTT, +then it is given an address. Two consequences of this are: the kernel +needs to edit the batchbuffer submitted to write the correct value of +the GPU address when a GEM BO is assigned a GPU address and the kernel +might evict a different GEM BO from the (PP)GTT to make address room +for another GEM BO. Consequently, the ioctls submitting a batchbuffer +for execution also include a list of all locations within buffers that +refer to GPU-addresses so that the kernel can edit the buffer correctly. +This process is dubbed relocation. + +GEM BO Management Implementation Details +---------------------------------------- + +.. kernel-doc:: drivers/gpu/drm/i915/i915_vma.h + :doc: Virtual Memory Address + +Buffer Object Eviction +---------------------- + +This section documents the interface functions for evicting buffer +objects to make space available in the virtual gpu address spaces. Note +that this is mostly orthogonal to shrinking buffer objects caches, which +has the goal to make main memory (shared with the gpu through the +unified memory architecture) available. + +.. kernel-doc:: drivers/gpu/drm/i915/i915_gem_evict.c + :internal: + +Buffer Object Memory Shrinking +------------------------------ + +This section documents the interface function for shrinking memory usage +of buffer object caches. Shrinking is used to make main memory +available. Note that this is mostly orthogonal to evicting buffer +objects, which has the goal to make space in gpu virtual address spaces. + +.. kernel-doc:: drivers/gpu/drm/i915/i915_gem_shrinker.c + :internal: + Batchbuffer Parsing ------------------- @@ -267,6 +370,12 @@ Batchbuffer Pools .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_batch_pool.c :internal: +User Batchbuffer Execution +-------------------------- + +.. kernel-doc:: drivers/gpu/drm/i915/i915_gem_execbuffer.c + :doc: User command execution + Logical Rings, Logical Ring Contexts and Execlists -------------------------------------------------- @@ -312,28 +421,14 @@ Object Tiling IOCTLs .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_tiling.c :doc: buffer object tiling -Buffer Object Eviction ----------------------- - -This section documents the interface functions for evicting buffer -objects to make space available in the virtual gpu address spaces. Note -that this is mostly orthogonal to shrinking buffer objects caches, which -has the goal to make main memory (shared with the gpu through the -unified memory architecture) available. - -.. kernel-doc:: drivers/gpu/drm/i915/i915_gem_evict.c - :internal: - -Buffer Object Memory Shrinking ------------------------------- +WOPCM +===== -This section documents the interface function for shrinking memory usage -of buffer object caches. Shrinking is used to make main memory -available. Note that this is mostly orthogonal to evicting buffer -objects, which has the goal to make space in gpu virtual address spaces. +WOPCM Layout +------------ -.. kernel-doc:: drivers/gpu/drm/i915/i915_gem_shrinker.c - :internal: +.. kernel-doc:: drivers/gpu/drm/i915/intel_wopcm.c + :doc: WOPCM Layout GuC === @@ -359,6 +454,12 @@ GuC Firmware Layout .. kernel-doc:: drivers/gpu/drm/i915/intel_guc_fwif.h :doc: GuC Firmware Layout +GuC Address Space +----------------- + +.. kernel-doc:: drivers/gpu/drm/i915/intel_guc.c + :doc: GuC Address Space + Tracing ======= diff --git a/Documentation/gpu/kms-properties.csv b/Documentation/gpu/kms-properties.csv index 6b28b014cb7d..07ed22ea3bd6 100644 --- a/Documentation/gpu/kms-properties.csv +++ b/Documentation/gpu/kms-properties.csv @@ -98,5 +98,4 @@ radeon,DVI-I,“coherent”,RANGE,"Min=0, Max=1",Connector,TBD ,,"""underscan vborder""",RANGE,"Min=0, Max=128",Connector,TBD ,Audio,“audio”,ENUM,"{ ""off"", ""on"", ""auto"" }",Connector,TBD ,FMT Dithering,“dither”,ENUM,"{ ""off"", ""on"" }",Connector,TBD -rcar-du,Generic,"""alpha""",RANGE,"Min=0, Max=255",Plane,TBD ,,"""colorkey""",RANGE,"Min=0, Max=0x01ffffff",Plane,TBD diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst index f4d0b3476d9c..a7c150d6b63f 100644 --- a/Documentation/gpu/todo.rst +++ b/Documentation/gpu/todo.rst @@ -212,6 +212,24 @@ probably use drm_fb_helper_fbdev_teardown(). Contact: Maintainer of the driver you plan to convert +Clean up mmap forwarding +------------------------ + +A lot of drivers forward gem mmap calls to dma-buf mmap for imported buffers. +And also a lot of them forward dma-buf mmap to the gem mmap implementations. +Would be great to refactor this all into a set of small common helpers. + +Contact: Daniel Vetter + +Put a reservation_object into drm_gem_object +-------------------------------------------- + +This would remove the need for the ->gem_prime_res_obj callback. It would also +allow us to implement generic helpers for waiting for a bo, allowing for quite a +bit of refactoring in the various wait ioctl implementations. + +Contact: Daniel Vetter + idr_init_base() --------------- diff --git a/Documentation/gpu/xen-front.rst b/Documentation/gpu/xen-front.rst new file mode 100644 index 000000000000..d988da7d1983 --- /dev/null +++ b/Documentation/gpu/xen-front.rst @@ -0,0 +1,31 @@ +==================================================== + drm/xen-front Xen para-virtualized frontend driver +==================================================== + +This frontend driver implements Xen para-virtualized display +according to the display protocol described at +include/xen/interface/io/displif.h + +Driver modes of operation in terms of display buffers used +========================================================== + +.. kernel-doc:: drivers/gpu/drm/xen/xen_drm_front.h + :doc: Driver modes of operation in terms of display buffers used + +Buffers allocated by the frontend driver +---------------------------------------- + +.. kernel-doc:: drivers/gpu/drm/xen/xen_drm_front.h + :doc: Buffers allocated by the frontend driver + +Buffers allocated by the backend +-------------------------------- + +.. kernel-doc:: drivers/gpu/drm/xen/xen_drm_front.h + :doc: Buffers allocated by the backend + +Driver limitations +================== + +.. kernel-doc:: drivers/gpu/drm/xen/xen_drm_front.h + :doc: Driver limitations diff --git a/Documentation/hwmon/adm1275 b/Documentation/hwmon/adm1275 index 791bc0bd91e6..39033538eb03 100644 --- a/Documentation/hwmon/adm1275 +++ b/Documentation/hwmon/adm1275 @@ -6,6 +6,10 @@ Supported chips: Prefix: 'adm1075' Addresses scanned: - Datasheet: www.analog.com/static/imported-files/data_sheets/ADM1075.pdf + * Analog Devices ADM1272 + Prefix: 'adm1272' + Addresses scanned: - + Datasheet: www.analog.com/static/imported-files/data_sheets/ADM1272.pdf * Analog Devices ADM1275 Prefix: 'adm1275' Addresses scanned: - @@ -29,11 +33,11 @@ Author: Guenter Roeck <linux@roeck-us.net> Description ----------- -This driver supports hardware monitoring for Analog Devices ADM1075, ADM1275, -ADM1276, ADM1278, ADM1293, and ADM1294 Hot-Swap Controller and Digital -Power Monitors. +This driver supports hardware monitoring for Analog Devices ADM1075, ADM1272, +ADM1275, ADM1276, ADM1278, ADM1293, and ADM1294 Hot-Swap Controller and +Digital Power Monitors. -ADM1075, ADM1275, ADM1276, ADM1278, ADM1293, and ADM1294 are hot-swap +ADM1075, ADM1272, ADM1275, ADM1276, ADM1278, ADM1293, and ADM1294 are hot-swap controllers that allow a circuit board to be removed from or inserted into a live backplane. They also feature current and voltage readback via an integrated 12 bit analog-to-digital converter (ADC), accessed using a @@ -100,11 +104,10 @@ power1_input_lowest Lowest observed input power. ADM1293 and ADM1294 only. power1_input_highest Highest observed input power. power1_reset_history Write any value to reset history. - Power attributes are supported on ADM1075, ADM1276, - ADM1293, and ADM1294. + Power attributes are supported on ADM1075, ADM1272, + ADM1276, ADM1293, and ADM1294. temp1_input Chip temperature. - Temperature attributes are only available on ADM1278. temp1_max Maximum chip temperature. temp1_max_alarm Temperature alarm. temp1_crit Critical chip temperature. @@ -112,4 +115,5 @@ temp1_crit_alarm Critical temperature high alarm. temp1_highest Highest observed temperature. temp1_reset_history Write any value to reset history. - Temperature attributes are supported on ADM1278. + Temperature attributes are supported on ADM1272 and + ADM1278. diff --git a/Documentation/hwmon/hwmon-kernel-api.txt b/Documentation/hwmon/hwmon-kernel-api.txt index 53a806696c64..eb7a78aebb38 100644 --- a/Documentation/hwmon/hwmon-kernel-api.txt +++ b/Documentation/hwmon/hwmon-kernel-api.txt @@ -71,7 +71,8 @@ hwmon_device_register_with_info is the most comprehensive and preferred means to register a hardware monitoring device. It creates the standard sysfs attributes in the hardware monitoring core, letting the driver focus on reading from and writing to the chip instead of having to bother with sysfs attributes. -Its parameters are described in more detail below. +The parent device parameter cannot be NULL with non-NULL chip info. Its +parameters are described in more detail below. devm_hwmon_device_register_with_info is similar to hwmon_device_register_with_info. However, it is device managed, meaning the diff --git a/Documentation/hwmon/lm92 b/Documentation/hwmon/lm92 index 22f68ad032cf..cfa99a353b8c 100644 --- a/Documentation/hwmon/lm92 +++ b/Documentation/hwmon/lm92 @@ -11,10 +11,8 @@ Supported chips: Addresses scanned: none, force parameter needed Datasheet: http://www.national.com/pf/LM/LM76.html * Maxim MAX6633/MAX6634/MAX6635 - Prefix: 'lm92' - Addresses scanned: I2C 0x48 - 0x4b - MAX6633 with address in 0x40 - 0x47, 0x4c - 0x4f needs force parameter - and MAX6634 with address in 0x4c - 0x4f needs force parameter + Prefix: 'max6635' + Addresses scanned: none, force parameter needed Datasheet: http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3074 Authors: diff --git a/Documentation/hwmon/ltc2990 b/Documentation/hwmon/ltc2990 index c25211e90bdc..3ed68f676c0f 100644 --- a/Documentation/hwmon/ltc2990 +++ b/Documentation/hwmon/ltc2990 @@ -8,6 +8,7 @@ Supported chips: Datasheet: http://www.linear.com/product/ltc2990 Author: Mike Looijmans <mike.looijmans@topic.nl> + Tom Levens <tom.levens@cern.ch> Description @@ -16,10 +17,8 @@ Description LTC2990 is a Quad I2C Voltage, Current and Temperature Monitor. The chip's inputs can measure 4 voltages, or two inputs together (1+2 and 3+4) can be combined to measure a differential voltage, which is typically used to -measure current through a series resistor, or a temperature. - -This driver currently uses the 2x differential mode only. In order to support -other modes, the driver will need to be expanded. +measure current through a series resistor, or a temperature with an external +diode. Usage Notes @@ -32,12 +31,19 @@ devices explicitly. Sysfs attributes ---------------- +in0_input Voltage at Vcc pin in millivolt (range 2.5V to 5V) +temp1_input Internal chip temperature in millidegrees Celcius + +A subset of the following attributes are visible, depending on the measurement +mode of the chip. + +in[1-4]_input Voltage at V[1-4] pin in millivolt +temp2_input External temperature sensor TR1 in millidegrees Celcius +temp3_input External temperature sensor TR2 in millidegrees Celcius +curr1_input Current in mA across V1-V2 assuming a 1mOhm sense resistor +curr2_input Current in mA across V3-V4 assuming a 1mOhm sense resistor + The "curr*_input" measurements actually report the voltage drop across the input pins in microvolts. This is equivalent to the current through a 1mOhm sense resistor. Divide the reported value by the actual sense resistor value in mOhm to get the actual value. - -in0_input Voltage at Vcc pin in millivolt (range 2.5V to 5V) -temp1_input Internal chip temperature in millidegrees Celcius -curr1_input Current in mA across v1-v2 assuming a 1mOhm sense resistor. -curr2_input Current in mA across v3-v4 assuming a 1mOhm sense resistor. diff --git a/Documentation/hwmon/nct6775 b/Documentation/hwmon/nct6775 index 76add4c9cd68..bd59834d310f 100644 --- a/Documentation/hwmon/nct6775 +++ b/Documentation/hwmon/nct6775 @@ -36,6 +36,14 @@ Supported chips: Prefix: 'nct6793' Addresses scanned: ISA address retrieved from Super I/O registers Datasheet: Available from Nuvoton upon request + * Nuvoton NCT6795D + Prefix: 'nct6795' + Addresses scanned: ISA address retrieved from Super I/O registers + Datasheet: Available from Nuvoton upon request + * Nuvoton NCT6796D + Prefix: 'nct6796' + Addresses scanned: ISA address retrieved from Super I/O registers + Datasheet: Available from Nuvoton upon request Authors: Guenter Roeck <linux@roeck-us.net> @@ -88,10 +96,10 @@ The mode works for fan1-fan5. sysfs attributes ---------------- -pwm[1-5] - this file stores PWM duty cycle or DC value (fan speed) in range: +pwm[1-7] - this file stores PWM duty cycle or DC value (fan speed) in range: 0 (lowest speed) to 255 (full) -pwm[1-5]_enable - this file controls mode of fan/temperature control: +pwm[1-7]_enable - this file controls mode of fan/temperature control: * 0 Fan control disabled (fans set to maximum speed) * 1 Manual mode, write to pwm[0-5] any value 0-255 * 2 "Thermal Cruise" mode @@ -99,16 +107,16 @@ pwm[1-5]_enable - this file controls mode of fan/temperature control: * 4 "Smart Fan III" mode (NCT6775F only) * 5 "Smart Fan IV" mode -pwm[1-5]_mode - controls if output is PWM or DC level +pwm[1-7]_mode - controls if output is PWM or DC level * 0 DC output * 1 PWM output Common fan control attributes ----------------------------- -pwm[1-5]_temp_sel Temperature source. Value is temperature sensor index. +pwm[1-7]_temp_sel Temperature source. Value is temperature sensor index. For example, select '1' for temp1_input. -pwm[1-5]_weight_temp_sel +pwm[1-7]_weight_temp_sel Secondary temperature source. Value is temperature sensor index. For example, select '1' for temp1_input. Set to 0 to disable secondary temperature control. @@ -116,16 +124,16 @@ pwm[1-5]_weight_temp_sel If secondary temperature functionality is enabled, it is controlled with the following attributes. -pwm[1-5]_weight_duty_step +pwm[1-7]_weight_duty_step Duty step size. -pwm[1-5]_weight_temp_step +pwm[1-7]_weight_temp_step Temperature step size. With each step over temp_step_base, the value of weight_duty_step is added to the current pwm value. -pwm[1-5]_weight_temp_step_base +pwm[1-7]_weight_temp_step_base Temperature at which secondary temperature control kicks in. -pwm[1-5]_weight_temp_step_tol +pwm[1-7]_weight_temp_step_tol Temperature step tolerance. Thermal Cruise mode (2) @@ -133,9 +141,9 @@ Thermal Cruise mode (2) If the temperature is in the range defined by: -pwm[1-5]_target_temp Target temperature, unit millidegree Celsius +pwm[1-7]_target_temp Target temperature, unit millidegree Celsius (range 0 - 127000) -pwm[1-5]_temp_tolerance +pwm[1-7]_temp_tolerance Target temperature tolerance, unit millidegree Celsius there are no changes to fan speed. Once the temperature leaves the interval, fan @@ -143,14 +151,14 @@ speed increases (if temperature is higher that desired) or decreases (if temperature is lower than desired), using the following limits and time intervals. -pwm[1-5]_start fan pwm start value (range 1 - 255), to start fan +pwm[1-7]_start fan pwm start value (range 1 - 255), to start fan when the temperature is above defined range. -pwm[1-5]_floor lowest fan pwm (range 0 - 255) if temperature is below +pwm[1-7]_floor lowest fan pwm (range 0 - 255) if temperature is below the defined range. If set to 0, the fan is expected to stop if the temperature is below the defined range. -pwm[1-5]_step_up_time milliseconds before fan speed is increased -pwm[1-5]_step_down_time milliseconds before fan speed is decreased -pwm[1-5]_stop_time how many milliseconds must elapse to switch +pwm[1-7]_step_up_time milliseconds before fan speed is increased +pwm[1-7]_step_down_time milliseconds before fan speed is decreased +pwm[1-7]_stop_time how many milliseconds must elapse to switch corresponding fan off (when the temperature was below defined range). @@ -159,8 +167,8 @@ Speed Cruise mode (3) This modes tries to keep the fan speed constant. -fan[1-5]_target Target fan speed -fan[1-5]_tolerance +fan[1-7]_target Target fan speed +fan[1-7]_tolerance Target speed tolerance @@ -177,19 +185,19 @@ points should be set to higher temperatures and higher pwm values to achieve higher fan speeds with increasing temperature. The last data point reflects critical temperature mode, in which the fans should run at full speed. -pwm[1-5]_auto_point[1-7]_pwm +pwm[1-7]_auto_point[1-7]_pwm pwm value to be set if temperature reaches matching temperature range. -pwm[1-5]_auto_point[1-7]_temp +pwm[1-7]_auto_point[1-7]_temp Temperature over which the matching pwm is enabled. -pwm[1-5]_temp_tolerance +pwm[1-7]_temp_tolerance Temperature tolerance, unit millidegree Celsius -pwm[1-5]_crit_temp_tolerance +pwm[1-7]_crit_temp_tolerance Temperature tolerance for critical temperature, unit millidegree Celsius -pwm[1-5]_step_up_time milliseconds before fan speed is increased -pwm[1-5]_step_down_time milliseconds before fan speed is decreased +pwm[1-7]_step_up_time milliseconds before fan speed is increased +pwm[1-7]_step_down_time milliseconds before fan speed is decreased Usage Notes ----------- diff --git a/Documentation/hwmon/sht21 b/Documentation/hwmon/sht21 index 47f4765db256..8b3cdda541c1 100644 --- a/Documentation/hwmon/sht21 +++ b/Documentation/hwmon/sht21 @@ -6,13 +6,13 @@ Supported chips: Prefix: 'sht21' Addresses scanned: none Datasheet: Publicly available at the Sensirion website - http://www.sensirion.com/en/pdf/product_information/Datasheet-humidity-sensor-SHT21.pdf + http://www.sensirion.com/file/datasheet_sht21 * Sensirion SHT25 - Prefix: 'sht21' + Prefix: 'sht25' Addresses scanned: none Datasheet: Publicly available at the Sensirion website - http://www.sensirion.com/en/pdf/product_information/Datasheet-humidity-sensor-SHT25.pdf + http://www.sensirion.com/file/datasheet_sht25 Author: Urs Fleisch <urs.fleisch@sensirion.com> diff --git a/Documentation/hwmon/sht3x b/Documentation/hwmon/sht3x index b0d88184f48e..d9daa6ab1e8e 100644 --- a/Documentation/hwmon/sht3x +++ b/Documentation/hwmon/sht3x @@ -5,7 +5,7 @@ Supported chips: * Sensirion SHT3x-DIS Prefix: 'sht3x' Addresses scanned: none - Datasheet: http://www.sensirion.com/fileadmin/user_upload/customers/sensirion/Dokumente/Humidity/Sensirion_Humidity_Datasheet_SHT3x_DIS.pdf + Datasheet: https://www.sensirion.com/file/datasheet_sht3x_digital Author: David Frey <david.frey@sensirion.com> diff --git a/Documentation/i2c/busses/i2c-ocores b/Documentation/i2c/busses/i2c-ocores index c269aaa2f26a..9e1dfe7553ad 100644 --- a/Documentation/i2c/busses/i2c-ocores +++ b/Documentation/i2c/busses/i2c-ocores @@ -2,7 +2,7 @@ Kernel driver i2c-ocores Supported adapters: * OpenCores.org I2C controller by Richard Herveille (see datasheet link) - Datasheet: http://www.opencores.org/projects.cgi/web/i2c/overview + https://opencores.org/project/i2c/overview Author: Peter Korsgaard <jacmet@sunsite.dk> diff --git a/Documentation/i2c/dev-interface b/Documentation/i2c/dev-interface index d04e6e4964ee..fbed645ccd75 100644 --- a/Documentation/i2c/dev-interface +++ b/Documentation/i2c/dev-interface @@ -9,8 +9,8 @@ i2c adapters present on your system at a given time. i2cdetect is part of the i2c-tools package. I2C device files are character device files with major device number 89 -and a minor device number corresponding to the number assigned as -explained above. They should be called "i2c-%d" (i2c-0, i2c-1, ..., +and a minor device number corresponding to the number assigned as +explained above. They should be called "i2c-%d" (i2c-0, i2c-1, ..., i2c-10, ...). All 256 minor device numbers are reserved for i2c. @@ -23,11 +23,6 @@ First, you need to include these two headers: #include <linux/i2c-dev.h> #include <i2c/smbus.h> -(Please note that there are two files named "i2c-dev.h" out there. One is -distributed with the Linux kernel and the other one is included in the -source tree of i2c-tools. They used to be different in content but since 2012 -they're identical. You should use "linux/i2c-dev.h"). - Now, you have to decide which adapter you want to access. You should inspect /sys/class/i2c-dev/ or run "i2cdetect -l" to decide this. Adapter numbers are assigned somewhat dynamically, so you can not @@ -38,7 +33,7 @@ Next thing, open the device file, as follows: int file; int adapter_nr = 2; /* probably dynamically determined */ char filename[20]; - + snprintf(filename, 19, "/dev/i2c-%d", adapter_nr); file = open(filename, O_RDWR); if (file < 0) { @@ -72,8 +67,10 @@ the device supports them. Both are illustrated below. /* res contains the read word */ } - /* Using I2C Write, equivalent of - i2c_smbus_write_word_data(file, reg, 0x6543) */ + /* + * Using I2C Write, equivalent of + * i2c_smbus_write_word_data(file, reg, 0x6543) + */ buf[0] = reg; buf[1] = 0x43; buf[2] = 0x65; @@ -140,14 +137,14 @@ ioctl(file, I2C_RDWR, struct i2c_rdwr_ioctl_data *msgset) set in each message, overriding the values set with the above ioctl's. ioctl(file, I2C_SMBUS, struct i2c_smbus_ioctl_data *args) - Not meant to be called directly; instead, use the access functions - below. + If possible, use the provided i2c_smbus_* methods described below instead + of issuing direct ioctls. You can do plain i2c transactions by using read(2) and write(2) calls. You do not need to pass the address byte; instead, set it through ioctl I2C_SLAVE before you try to access the device. -You can do SMBus level transactions (see documentation file smbus-protocol +You can do SMBus level transactions (see documentation file smbus-protocol for details) through the following functions: __s32 i2c_smbus_write_quick(int file, __u8 value); __s32 i2c_smbus_read_byte(int file); @@ -158,7 +155,7 @@ for details) through the following functions: __s32 i2c_smbus_write_word_data(int file, __u8 command, __u16 value); __s32 i2c_smbus_process_call(int file, __u8 command, __u16 value); __s32 i2c_smbus_read_block_data(int file, __u8 command, __u8 *values); - __s32 i2c_smbus_write_block_data(int file, __u8 command, __u8 length, + __s32 i2c_smbus_write_block_data(int file, __u8 command, __u8 length, __u8 *values); All these transactions return -1 on failure; you can read errno to see what happened. The 'write' transactions return 0 on success; the @@ -166,10 +163,9 @@ what happened. The 'write' transactions return 0 on success; the returns the number of values read. The block buffers need not be longer than 32 bytes. -The above functions are all inline functions, that resolve to calls to -the i2c_smbus_access function, that on its turn calls a specific ioctl -with the data in a specific format. Read the source code if you -want to know what happens behind the screens. +The above functions are made available by linking against the libi2c library, +which is provided by the i2c-tools project. See: +https://git.kernel.org/pub/scm/utils/i2c-tools/i2c-tools.git/. Implementation details diff --git a/Documentation/index.rst b/Documentation/index.rst index 3b99ab931d41..fdc585703498 100644 --- a/Documentation/index.rst +++ b/Documentation/index.rst @@ -45,7 +45,7 @@ the kernel interface as seen by application developers. .. toctree:: :maxdepth: 2 - userspace-api/index + userspace-api/index Introduction to kernel development @@ -89,6 +89,7 @@ needed). sound/index crypto/index filesystems/index + vm/index Architecture-specific documentation ----------------------------------- diff --git a/Documentation/ioctl/botching-up-ioctls.txt b/Documentation/ioctl/botching-up-ioctls.txt index d02cfb48901c..883fb034bd04 100644 --- a/Documentation/ioctl/botching-up-ioctls.txt +++ b/Documentation/ioctl/botching-up-ioctls.txt @@ -73,7 +73,9 @@ will have a second iteration or at least an extension for any given interface. future extensions is going right down the gutters since someone will submit an ioctl struct with random stack garbage in the yet unused parts. Which then bakes in the ABI that those fields can never be used for anything else - but garbage. + but garbage. This is also the reason why you must explicitly pad all + structures, even if you never use them in an array - the padding the compiler + might insert could contain garbage. * Have simple testcases for all of the above. diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt index 84bb74dcae12..a12488d45c40 100644 --- a/Documentation/ioctl/ioctl-number.txt +++ b/Documentation/ioctl/ioctl-number.txt @@ -217,7 +217,6 @@ Code Seq#(hex) Include File Comments 'd' 02-40 pcmcia/ds.h conflict! 'd' F0-FF linux/digi1.h 'e' all linux/digi1.h conflict! -'e' 00-1F drivers/net/irda/irtty-sir.h conflict! 'f' 00-1F linux/ext2_fs.h conflict! 'f' 00-1F linux/ext3_fs.h conflict! 'f' 00-0F fs/jfs/jfs_dinode.h conflict! @@ -247,7 +246,6 @@ Code Seq#(hex) Include File Comments 'm' all linux/synclink.h conflict! 'm' 00-19 drivers/message/fusion/mptctl.h conflict! 'm' 00 drivers/scsi/megaraid/megaraid_ioctl.h conflict! -'m' 00-1F net/irda/irmod.h conflict! 'n' 00-7F linux/ncp_fs.h and fs/ncpfs/ioctl.c 'n' 80-8F uapi/linux/nilfs2_api.h NILFS2 'n' E0-FF linux/matroxfb.h matroxfb @@ -298,7 +296,8 @@ Code Seq#(hex) Include File Comments 0x90 00 drivers/cdrom/sbpcd.h 0x92 00-0F drivers/usb/mon/mon_bin.c 0x93 60-7F linux/auto_fs.h -0x94 all fs/btrfs/ioctl.h +0x94 all fs/btrfs/ioctl.h Btrfs filesystem + and linux/fs.h some lifted to vfs/generic 0x97 00-7F fs/ceph/ioctl.h Ceph file system 0x99 00-0F 537-Addinboard driver <mailto:buk@buks.ipn.de> @@ -329,6 +328,7 @@ Code Seq#(hex) Include File Comments 0xCA 80-BF uapi/scsi/cxlflash_ioctl.h 0xCB 00-1F CBM serial IEC bus in development: <mailto:michael.klein@puffin.lb.shuttle.de> +0xCC 00-0F drivers/misc/ibmvmc.h pseries VMC driver 0xCD 01 linux/reiserfs_fs.h 0xCF 02 fs/cifs/ioctl.c 0xDB 00-0F drivers/char/mwave/mwavepub.h diff --git a/Documentation/kbuild/kconfig-language.txt b/Documentation/kbuild/kconfig-language.txt index f5b9493f04ad..0e966e8f9ec7 100644 --- a/Documentation/kbuild/kconfig-language.txt +++ b/Documentation/kbuild/kconfig-language.txt @@ -198,14 +198,6 @@ applicable everywhere (see syntax). enables the third modular state for all config symbols. At most one symbol may have the "modules" option set. - - "env"=<value> - This imports the environment variable into Kconfig. It behaves like - a default, except that the value comes from the environment, this - also means that the behaviour when mixing it with normal defaults is - undefined at this point. The symbol is currently not exported back - to the build environment (if this is desired, it can be done via - another symbol). - - "allnoconfig_y" This declares the symbol as one that should have the value y when using "allnoconfig". Used for symbols that hide other symbols. diff --git a/Documentation/kbuild/kconfig-macro-language.txt b/Documentation/kbuild/kconfig-macro-language.txt new file mode 100644 index 000000000000..07da2ea68dce --- /dev/null +++ b/Documentation/kbuild/kconfig-macro-language.txt @@ -0,0 +1,242 @@ +Concept +------- + +The basic idea was inspired by Make. When we look at Make, we notice sort of +two languages in one. One language describes dependency graphs consisting of +targets and prerequisites. The other is a macro language for performing textual +substitution. + +There is clear distinction between the two language stages. For example, you +can write a makefile like follows: + + APP := foo + SRC := foo.c + CC := gcc + + $(APP): $(SRC) + $(CC) -o $(APP) $(SRC) + +The macro language replaces the variable references with their expanded form, +and handles as if the source file were input like follows: + + foo: foo.c + gcc -o foo foo.c + +Then, Make analyzes the dependency graph and determines the targets to be +updated. + +The idea is quite similar in Kconfig - it is possible to describe a Kconfig +file like this: + + CC := gcc + + config CC_HAS_FOO + def_bool $(shell, $(srctree)/scripts/gcc-check-foo.sh $(CC)) + +The macro language in Kconfig processes the source file into the following +intermediate: + + config CC_HAS_FOO + def_bool y + +Then, Kconfig moves onto the evaluation stage to resolve inter-symbol +dependency as explained in kconfig-language.txt. + + +Variables +--------- + +Like in Make, a variable in Kconfig works as a macro variable. A macro +variable is expanded "in place" to yield a text string that may then be +expanded further. To get the value of a variable, enclose the variable name in +$( ). The parentheses are required even for single-letter variable names; $X is +a syntax error. The curly brace form as in ${CC} is not supported either. + +There are two types of variables: simply expanded variables and recursively +expanded variables. + +A simply expanded variable is defined using the := assignment operator. Its +righthand side is expanded immediately upon reading the line from the Kconfig +file. + +A recursively expanded variable is defined using the = assignment operator. +Its righthand side is simply stored as the value of the variable without +expanding it in any way. Instead, the expansion is performed when the variable +is used. + +There is another type of assignment operator; += is used to append text to a +variable. The righthand side of += is expanded immediately if the lefthand +side was originally defined as a simple variable. Otherwise, its evaluation is +deferred. + +The variable reference can take parameters, in the following form: + + $(name,arg1,arg2,arg3) + +You can consider the parameterized reference as a function. (more precisely, +"user-defined function" in contrast to "built-in function" listed below). + +Useful functions must be expanded when they are used since the same function is +expanded differently if different parameters are passed. Hence, a user-defined +function is defined using the = assignment operator. The parameters are +referenced within the body definition with $(1), $(2), etc. + +In fact, recursively expanded variables and user-defined functions are the same +internally. (In other words, "variable" is "function with zero argument".) +When we say "variable" in a broad sense, it includes "user-defined function". + + +Built-in functions +------------------ + +Like Make, Kconfig provides several built-in functions. Every function takes a +particular number of arguments. + +In Make, every built-in function takes at least one argument. Kconfig allows +zero argument for built-in functions, such as $(fileno), $(lineno). You could +consider those as "built-in variable", but it is just a matter of how we call +it after all. Let's say "built-in function" here to refer to natively supported +functionality. + +Kconfig currently supports the following built-in functions. + + - $(shell,command) + + The "shell" function accepts a single argument that is expanded and passed + to a subshell for execution. The standard output of the command is then read + and returned as the value of the function. Every newline in the output is + replaced with a space. Any trailing newlines are deleted. The standard error + is not returned, nor is any program exit status. + + - $(info,text) + + The "info" function takes a single argument and prints it to stdout. + It evaluates to an empty string. + + - $(warning-if,condition,text) + + The "warning-if" function takes two arguments. If the condition part is "y", + the text part is sent to stderr. The text is prefixed with the name of the + current Kconfig file and the current line number. + + - $(error-if,condition,text) + + The "error-if" function is similar to "warning-if", but it terminates the + parsing immediately if the condition part is "y". + + - $(filename) + + The 'filename' takes no argument, and $(filename) is expanded to the file + name being parsed. + + - $(lineno) + + The 'lineno' takes no argument, and $(lineno) is expanded to the line number + being parsed. + + +Make vs Kconfig +--------------- + +Kconfig adopts Make-like macro language, but the function call syntax is +slightly different. + +A function call in Make looks like this: + + $(func-name arg1,arg2,arg3) + +The function name and the first argument are separated by at least one +whitespace. Then, leading whitespaces are trimmed from the first argument, +while whitespaces in the other arguments are kept. You need to use a kind of +trick to start the first parameter with spaces. For example, if you want +to make "info" function print " hello", you can write like follows: + + empty := + space := $(empty) $(empty) + $(info $(space)$(space)hello) + +Kconfig uses only commas for delimiters, and keeps all whitespaces in the +function call. Some people prefer putting a space after each comma delimiter: + + $(func-name, arg1, arg2, arg3) + +In this case, "func-name" will receive " arg1", " arg2", " arg3". The presence +of leading spaces may matter depending on the function. The same applies to +Make - for example, $(subst .c, .o, $(sources)) is a typical mistake; it +replaces ".c" with " .o". + +In Make, a user-defined function is referenced by using a built-in function, +'call', like this: + + $(call my-func,arg1,arg2,arg3) + +Kconfig invokes user-defined functions and built-in functions in the same way. +The omission of 'call' makes the syntax shorter. + +In Make, some functions treat commas verbatim instead of argument separators. +For example, $(shell echo hello, world) runs the command "echo hello, world". +Likewise, $(info hello, world) prints "hello, world" to stdout. You could say +this is _useful_ inconsistency. + +In Kconfig, for simpler implementation and grammatical consistency, commas that +appear in the $( ) context are always delimiters. It means + + $(shell, echo hello, world) + +is an error because it is passing two parameters where the 'shell' function +accepts only one. To pass commas in arguments, you can use the following trick: + + comma := , + $(shell, echo hello$(comma) world) + + +Caveats +------- + +A variable (or function) cannot be expanded across tokens. So, you cannot use +a variable as a shorthand for an expression that consists of multiple tokens. +The following works: + + RANGE_MIN := 1 + RANGE_MAX := 3 + + config FOO + int "foo" + range $(RANGE_MIN) $(RANGE_MAX) + +But, the following does not work: + + RANGES := 1 3 + + config FOO + int "foo" + range $(RANGES) + +A variable cannot be expanded to any keyword in Kconfig. The following does +not work: + + MY_TYPE := tristate + + config FOO + $(MY_TYPE) "foo" + default y + +Obviously from the design, $(shell command) is expanded in the textual +substitution phase. You cannot pass symbols to the 'shell' function. +The following does not work as expected. + + config ENDIAN_FLAG + string + default "-mbig-endian" if CPU_BIG_ENDIAN + default "-mlittle-endian" if CPU_LITTLE_ENDIAN + + config CC_HAS_ENDIAN_FLAG + def_bool $(shell $(srctree)/scripts/gcc-check-flag ENDIAN_FLAG) + +Instead, you can do like follows so that any function call is statically +expanded. + + config CC_HAS_ENDIAN_FLAG + bool + default $(shell $(srctree)/scripts/gcc-check-flag -mbig-endian) if CPU_BIG_ENDIAN + default $(shell $(srctree)/scripts/gcc-check-flag -mlittle-endian) if CPU_LITTLE_ENDIAN diff --git a/Documentation/livepatch/shadow-vars.txt b/Documentation/livepatch/shadow-vars.txt index 89c66634d600..ecc09a7be5dd 100644 --- a/Documentation/livepatch/shadow-vars.txt +++ b/Documentation/livepatch/shadow-vars.txt @@ -34,9 +34,13 @@ meta-data and shadow-data: - data[] - storage for shadow data It is important to note that the klp_shadow_alloc() and -klp_shadow_get_or_alloc() calls, described below, store a *copy* of the -data that the functions are provided. Callers should provide whatever -mutual exclusion is required of the shadow data. +klp_shadow_get_or_alloc() are zeroing the variable by default. +They also allow to call a custom constructor function when a non-zero +value is needed. Callers should provide whatever mutual exclusion +is required. + +Note that the constructor is called under klp_shadow_lock spinlock. It allows +to do actions that can be done only once when a new variable is allocated. * klp_shadow_get() - retrieve a shadow variable data pointer - search hashtable for <obj, id> pair @@ -47,7 +51,7 @@ mutual exclusion is required of the shadow data. - WARN and return NULL - if <obj, id> doesn't already exist - allocate a new shadow variable - - copy data into the new shadow variable + - initialize the variable using a custom constructor and data when provided - add <obj, id> to the global hashtable * klp_shadow_get_or_alloc() - get existing or alloc a new shadow variable @@ -56,16 +60,20 @@ mutual exclusion is required of the shadow data. - return existing shadow variable - if <obj, id> doesn't already exist - allocate a new shadow variable - - copy data into the new shadow variable + - initialize the variable using a custom constructor and data when provided - add <obj, id> pair to the global hashtable * klp_shadow_free() - detach and free a <obj, id> shadow variable - find and remove a <obj, id> reference from global hashtable - - if found, free shadow variable + - if found + - call destructor function if defined + - free shadow variable * klp_shadow_free_all() - detach and free all <*, id> shadow variables - find and remove any <*, id> references from global hashtable - - if found, free shadow variable + - if found + - call destructor function if defined + - free shadow variable 2. Use cases @@ -107,7 +115,8 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata, sta = kzalloc(sizeof(*sta) + hw->sta_data_size, gfp); /* Attach a corresponding shadow variable, then initialize it */ - ps_lock = klp_shadow_alloc(sta, PS_LOCK, NULL, sizeof(*ps_lock), gfp); + ps_lock = klp_shadow_alloc(sta, PS_LOCK, sizeof(*ps_lock), gfp, + NULL, NULL); if (!ps_lock) goto shadow_fail; spin_lock_init(ps_lock); @@ -131,7 +140,7 @@ variable: void sta_info_free(struct ieee80211_local *local, struct sta_info *sta) { - klp_shadow_free(sta, PS_LOCK); + klp_shadow_free(sta, PS_LOCK, NULL); kfree(sta); ... @@ -148,16 +157,24 @@ shadow variables to parents already in-flight. For commit 1d147bfa6429, a good spot to allocate a shadow spinlock is inside ieee80211_sta_ps_deliver_wakeup(): +int ps_lock_shadow_ctor(void *obj, void *shadow_data, void *ctor_data) +{ + spinlock_t *lock = shadow_data; + + spin_lock_init(lock); + return 0; +} + #define PS_LOCK 1 void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta) { - DEFINE_SPINLOCK(ps_lock_fallback); spinlock_t *ps_lock; /* sync with ieee80211_tx_h_unicast_ps_buf */ ps_lock = klp_shadow_get_or_alloc(sta, PS_LOCK, - &ps_lock_fallback, sizeof(ps_lock_fallback), - GFP_ATOMIC); + sizeof(*ps_lock), GFP_ATOMIC, + ps_lock_shadow_ctor, NULL); + if (ps_lock) spin_lock(ps_lock); ... diff --git a/Documentation/media/kapi/v4l2-dev.rst b/Documentation/media/kapi/v4l2-dev.rst index 7bb0505b60f1..eb03ccc41c41 100644 --- a/Documentation/media/kapi/v4l2-dev.rst +++ b/Documentation/media/kapi/v4l2-dev.rst @@ -31,7 +31,7 @@ of the video device exits. The default :c:func:`video_device_release` callback currently just calls ``kfree`` to free the allocated memory. -There is also a ::c:func:`video_device_release_empty` function that does +There is also a :c:func:`video_device_release_empty` function that does nothing (is empty) and should be used if the struct is embedded and there is nothing to do when it is released. diff --git a/Documentation/media/uapi/mediactl/media-ioc-enum-entities.rst b/Documentation/media/uapi/mediactl/media-ioc-enum-entities.rst index 45e76e5bc1ea..582fda488810 100644 --- a/Documentation/media/uapi/mediactl/media-ioc-enum-entities.rst +++ b/Documentation/media/uapi/mediactl/media-ioc-enum-entities.rst @@ -89,7 +89,7 @@ id's until they get an error. - - - - Entity type, see :ref:`media-entity-type` for details. + - Entity type, see :ref:`media-entity-functions` for details. - .. row 4 diff --git a/Documentation/media/uapi/mediactl/media-ioc-g-topology.rst b/Documentation/media/uapi/mediactl/media-ioc-g-topology.rst index c8f9ea37db2d..c4055ddf070a 100644 --- a/Documentation/media/uapi/mediactl/media-ioc-g-topology.rst +++ b/Documentation/media/uapi/mediactl/media-ioc-g-topology.rst @@ -205,13 +205,13 @@ desired arrays with the media graph elements. - ``function`` - - Entity main function, see :ref:`media-entity-type` for details. + - Entity main function, see :ref:`media-entity-functions` for details. - .. row 4 - __u32 - - ``reserved``\ [12] + - ``reserved``\ [6] - Reserved for future extensions. Drivers and applications must set this array to zero. @@ -334,7 +334,7 @@ desired arrays with the media graph elements. - __u32 - - ``reserved``\ [9] + - ``reserved``\ [5] - Reserved for future extensions. Drivers and applications must set this array to zero. @@ -390,7 +390,7 @@ desired arrays with the media graph elements. - __u32 - - ``reserved``\ [5] + - ``reserved``\ [6] - Reserved for future extensions. Drivers and applications must set this array to zero. diff --git a/Documentation/media/uapi/mediactl/media-types.rst b/Documentation/media/uapi/mediactl/media-types.rst index f92f10b7ffbd..2dda14bd89b7 100644 --- a/Documentation/media/uapi/mediactl/media-types.rst +++ b/Documentation/media/uapi/mediactl/media-types.rst @@ -7,11 +7,11 @@ Types and flags used to represent the media graph elements .. tabularcolumns:: |p{8.2cm}|p{10.3cm}| -.. _media-entity-type: +.. _media-entity-functions: .. cssclass:: longtable -.. flat-table:: Media entity types +.. flat-table:: Media entity functions :header-rows: 0 :stub-columns: 0 diff --git a/Documentation/media/uapi/rc/keytable.c.rst b/Documentation/media/uapi/rc/keytable.c.rst index e6ce1e3f5a78..217237f93b37 100644 --- a/Documentation/media/uapi/rc/keytable.c.rst +++ b/Documentation/media/uapi/rc/keytable.c.rst @@ -7,7 +7,7 @@ file: uapi/v4l/keytable.c /* keytable.c - This program allows checking/replacing keys at IR - Copyright (C) 2006-2009 Mauro Carvalho Chehab <mchehab@infradead.org> + Copyright (C) 2006-2009 Mauro Carvalho Chehab <mchehab@kernel.org> This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by diff --git a/Documentation/media/uapi/v4l/extended-controls.rst b/Documentation/media/uapi/v4l/extended-controls.rst index d5f3eb6e674a..03931f9b1285 100644 --- a/Documentation/media/uapi/v4l/extended-controls.rst +++ b/Documentation/media/uapi/v4l/extended-controls.rst @@ -3565,7 +3565,7 @@ enum v4l2_dv_it_content_type - HDMI carries 5V on one of the pins). This is often used to power an eeprom which contains EDID information, such that the source can read the EDID even if the sink is in standby/power off. Each bit - corresponds to an input pad on the transmitter. If an input pad + corresponds to an input pad on the receiver. If an input pad cannot detect whether power is present, then the bit for that pad will be 0. This read-only control is applicable to DVI-D, HDMI and DisplayPort connectors. diff --git a/Documentation/media/uapi/v4l/pixfmt-v4l2-mplane.rst b/Documentation/media/uapi/v4l/pixfmt-v4l2-mplane.rst index 337e8188caf1..ef52f637d8e9 100644 --- a/Documentation/media/uapi/v4l/pixfmt-v4l2-mplane.rst +++ b/Documentation/media/uapi/v4l/pixfmt-v4l2-mplane.rst @@ -55,12 +55,14 @@ describing all planes of that format. - ``pixelformat`` - The pixel format. Both single- and multi-planar four character codes can be used. - * - enum :c:type:`v4l2_field` + * - __u32 - ``field`` - - See struct :c:type:`v4l2_pix_format`. - * - enum :c:type:`v4l2_colorspace` + - Field order, from enum :c:type:`v4l2_field`. + See struct :c:type:`v4l2_pix_format`. + * - __u32 - ``colorspace`` - - See struct :c:type:`v4l2_pix_format`. + - Colorspace encoding, from enum :c:type:`v4l2_colorspace`. + See struct :c:type:`v4l2_pix_format`. * - struct :c:type:`v4l2_plane_pix_format` - ``plane_fmt[VIDEO_MAX_PLANES]`` - An array of structures describing format of each plane this pixel @@ -73,24 +75,34 @@ describing all planes of that format. * - __u8 - ``flags`` - Flags set by the application or driver, see :ref:`format-flags`. - * - enum :c:type:`v4l2_ycbcr_encoding` + * - union { + - (anonymous) + - + * - __u8 - ``ycbcr_enc`` - - This information supplements the ``colorspace`` and must be set by + - Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`. + This information supplements the ``colorspace`` and must be set by the driver for capture streams and by the application for output streams, see :ref:`colorspaces`. - * - enum :c:type:`v4l2_hsv_encoding` + * - __u8 - ``hsv_enc`` - - This information supplements the ``colorspace`` and must be set by + - HSV encoding, from enum :c:type:`v4l2_hsv_encoding`. + This information supplements the ``colorspace`` and must be set by the driver for capture streams and by the application for output streams, see :ref:`colorspaces`. - * - enum :c:type:`v4l2_quantization` + * - } + - + - + * - __u8 - ``quantization`` - - This information supplements the ``colorspace`` and must be set by + - Quantization range, from enum :c:type:`v4l2_quantization`. + This information supplements the ``colorspace`` and must be set by the driver for capture streams and by the application for output streams, see :ref:`colorspaces`. - * - enum :c:type:`v4l2_xfer_func` + * - __u8 - ``xfer_func`` - - This information supplements the ``colorspace`` and must be set by + - Transfer function, from enum :c:type:`v4l2_xfer_func`. + This information supplements the ``colorspace`` and must be set by the driver for capture streams and by the application for output streams, see :ref:`colorspaces`. * - __u8 diff --git a/Documentation/media/uapi/v4l/pixfmt-v4l2.rst b/Documentation/media/uapi/v4l/pixfmt-v4l2.rst index 6622938c1b41..826f2305da01 100644 --- a/Documentation/media/uapi/v4l/pixfmt-v4l2.rst +++ b/Documentation/media/uapi/v4l/pixfmt-v4l2.rst @@ -40,9 +40,10 @@ Single-planar format structure RGB formats in :ref:`rgb-formats`, YUV formats in :ref:`yuv-formats`, and reserved codes in :ref:`reserved-formats` - * - enum :c:type:`v4l2_field` + * - __u32 - ``field`` - - Video images are typically interlaced. Applications can request to + - Field order, from enum :c:type:`v4l2_field`. + Video images are typically interlaced. Applications can request to capture or output only the top or bottom field, or both fields interlaced or sequentially stored in one buffer or alternating in separate buffers. Drivers return the actual field order selected. @@ -82,9 +83,10 @@ Single-planar format structure driver. Usually this is ``bytesperline`` times ``height``. When the image consists of variable length compressed data this is the maximum number of bytes required to hold an image. - * - enum :c:type:`v4l2_colorspace` + * - __u32 - ``colorspace`` - - This information supplements the ``pixelformat`` and must be set + - Image colorspace, from enum :c:type:`v4l2_colorspace`. + This information supplements the ``pixelformat`` and must be set by the driver for capture streams and by the application for output streams, see :ref:`colorspaces`. * - __u32 @@ -116,23 +118,33 @@ Single-planar format structure * - __u32 - ``flags`` - Flags set by the application or driver, see :ref:`format-flags`. - * - enum :c:type:`v4l2_ycbcr_encoding` + * - union { + - (anonymous) + - + * - __u32 - ``ycbcr_enc`` - - This information supplements the ``colorspace`` and must be set by + - Y'CbCr encoding, from enum :c:type:`v4l2_ycbcr_encoding`. + This information supplements the ``colorspace`` and must be set by the driver for capture streams and by the application for output streams, see :ref:`colorspaces`. - * - enum :c:type:`v4l2_hsv_encoding` + * - __u32 - ``hsv_enc`` - - This information supplements the ``colorspace`` and must be set by + - HSV encoding, from enum :c:type:`v4l2_hsv_encoding`. + This information supplements the ``colorspace`` and must be set by the driver for capture streams and by the application for output streams, see :ref:`colorspaces`. - * - enum :c:type:`v4l2_quantization` + * - } + - + - + * - __u32 - ``quantization`` - - This information supplements the ``colorspace`` and must be set by + - Quantization range, from enum :c:type:`v4l2_quantization`. + This information supplements the ``colorspace`` and must be set by the driver for capture streams and by the application for output streams, see :ref:`colorspaces`. - * - enum :c:type:`v4l2_xfer_func` + * - __u32 - ``xfer_func`` - - This information supplements the ``colorspace`` and must be set by + - Transfer function, from enum :c:type:`v4l2_xfer_func`. + This information supplements the ``colorspace`` and must be set by the driver for capture streams and by the application for output streams, see :ref:`colorspaces`. diff --git a/Documentation/media/uapi/v4l/v4l2grab.c.rst b/Documentation/media/uapi/v4l/v4l2grab.c.rst index 5aabd0b7b089..f0d0ab6abd41 100644 --- a/Documentation/media/uapi/v4l/v4l2grab.c.rst +++ b/Documentation/media/uapi/v4l/v4l2grab.c.rst @@ -6,7 +6,7 @@ file: media/v4l/v4l2grab.c .. code-block:: c /* V4L2 video picture grabber - Copyright (C) 2009 Mauro Carvalho Chehab <mchehab@infradead.org> + Copyright (C) 2009 Mauro Carvalho Chehab <mchehab@kernel.org> This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt index 6dafc8085acc..a02d6bbfc9d0 100644 --- a/Documentation/memory-barriers.txt +++ b/Documentation/memory-barriers.txt @@ -1920,9 +1920,6 @@ There are some more advanced barrier functions: /* assign ownership */ desc->status = DEVICE_OWN; - /* force memory to sync before notifying device via MMIO */ - wmb(); - /* notify device of new descriptors */ writel(DESC_NOTIFY, doorbell); } @@ -1930,11 +1927,15 @@ There are some more advanced barrier functions: The dma_rmb() allows us guarantee the device has released ownership before we read the data from the descriptor, and the dma_wmb() allows us to guarantee the data is written to the descriptor before the device - can see it now has ownership. The wmb() is needed to guarantee that the - cache coherent memory writes have completed before attempting a write to - the cache incoherent MMIO region. + can see it now has ownership. Note that, when using writel(), a prior + wmb() is not needed to guarantee that the cache coherent memory writes + have completed before writing to the MMIO region. The cheaper + writel_relaxed() does not provide this guarantee and must not be used + here. - See Documentation/DMA-API.txt for more information on consistent memory. + See the subsection "Kernel I/O barrier effects" for more information on + relaxed I/O accessors and the Documentation/DMA-API.txt file for more + information on consistent memory. MMIO WRITE BARRIER @@ -2903,7 +2904,7 @@ is discarded from the CPU's cache and reloaded. To deal with this, the appropriate part of the kernel must invalidate the overlapping bits of the cache on each CPU. -See Documentation/cachetlb.txt for more information on cache management. +See Documentation/core-api/cachetlb.rst for more information on cache management. CACHE COHERENCY VS MMIO @@ -3083,7 +3084,7 @@ CIRCULAR BUFFERS Memory barriers can be used to implement circular buffering without the need of a lock to serialise the producer with the consumer. See: - Documentation/circular-buffers.txt + Documentation/core-api/circular-buffers.rst for details. diff --git a/Documentation/misc-devices/ibmvmc.rst b/Documentation/misc-devices/ibmvmc.rst new file mode 100644 index 000000000000..46ded79554d4 --- /dev/null +++ b/Documentation/misc-devices/ibmvmc.rst @@ -0,0 +1,226 @@ +.. SPDX-License-Identifier: GPL-2.0+ +====================================================== +IBM Virtual Management Channel Kernel Driver (IBMVMC) +====================================================== + +:Authors: + Dave Engebretsen <engebret@us.ibm.com>, + Adam Reznechek <adreznec@linux.vnet.ibm.com>, + Steven Royer <seroyer@linux.vnet.ibm.com>, + Bryant G. Ly <bryantly@linux.vnet.ibm.com>, + +Introduction +============ + +Note: Knowledge of virtualization technology is required to understand +this document. + +A good reference document would be: + +https://openpowerfoundation.org/wp-content/uploads/2016/05/LoPAPR_DRAFT_v11_24March2016_cmt1.pdf + +The Virtual Management Channel (VMC) is a logical device which provides an +interface between the hypervisor and a management partition. This interface +is like a message passing interface. This management partition is intended +to provide an alternative to systems that use a Hardware Management +Console (HMC) - based system management. + +The primary hardware management solution that is developed by IBM relies +on an appliance server named the Hardware Management Console (HMC), +packaged as an external tower or rack-mounted personal computer. In a +Power Systems environment, a single HMC can manage multiple POWER +processor-based systems. + +Management Application +---------------------- + +In the management partition, a management application exists which enables +a system administrator to configure the system’s partitioning +characteristics via a command line interface (CLI) or Representational +State Transfer Application (REST API's). + +The management application runs on a Linux logical partition on a +POWER8 or newer processor-based server that is virtualized by PowerVM. +System configuration, maintenance, and control functions which +traditionally require an HMC can be implemented in the management +application using a combination of HMC to hypervisor interfaces and +existing operating system methods. This tool provides a subset of the +functions implemented by the HMC and enables basic partition configuration. +The set of HMC to hypervisor messages supported by the management +application component are passed to the hypervisor over a VMC interface, +which is defined below. + +The VMC enables the management partition to provide basic partitioning +functions: + +- Logical Partitioning Configuration +- Start, and stop actions for individual partitions +- Display of partition status +- Management of virtual Ethernet +- Management of virtual Storage +- Basic system management + +Virtual Management Channel (VMC) +-------------------------------- + +A logical device, called the Virtual Management Channel (VMC), is defined +for communicating between the management application and the hypervisor. It +basically creates the pipes that enable virtualization management +software. This device is presented to a designated management partition as +a virtual device. + +This communication device uses Command/Response Queue (CRQ) and the +Remote Direct Memory Access (RDMA) interfaces. A three-way handshake is +defined that must take place to establish that both the hypervisor and +management partition sides of the channel are running prior to +sending/receiving any of the protocol messages. + +This driver also utilizes Transport Event CRQs. CRQ messages are sent +when the hypervisor detects one of the peer partitions has abnormally +terminated, or one side has called H_FREE_CRQ to close their CRQ. +Two new classes of CRQ messages are introduced for the VMC device. VMC +Administrative messages are used for each partition using the VMC to +communicate capabilities to their partner. HMC Interface messages are used +for the actual flow of HMC messages between the management partition and +the hypervisor. As most HMC messages far exceed the size of a CRQ buffer, +a virtual DMA (RMDA) of the HMC message data is done prior to each HMC +Interface CRQ message. Only the management partition drives RDMA +operations; hypervisors never directly cause the movement of message data. + + +Terminology +----------- +RDMA + Remote Direct Memory Access is DMA transfer from the server to its + client or from the server to its partner partition. DMA refers + to both physical I/O to and from memory operations and to memory + to memory move operations. +CRQ + Command/Response Queue a facility which is used to communicate + between partner partitions. Transport events which are signaled + from the hypervisor to partition are also reported in this queue. + +Example Management Partition VMC Driver Interface +================================================= + +This section provides an example for the management application +implementation where a device driver is used to interface to the VMC +device. This driver consists of a new device, for example /dev/ibmvmc, +which provides interfaces to open, close, read, write, and perform +ioctl’s against the VMC device. + +VMC Interface Initialization +---------------------------- + +The device driver is responsible for initializing the VMC when the driver +is loaded. It first creates and initializes the CRQ. Next, an exchange of +VMC capabilities is performed to indicate the code version and number of +resources available in both the management partition and the hypervisor. +Finally, the hypervisor requests that the management partition create an +initial pool of VMC buffers, one buffer for each possible HMC connection, +which will be used for management application session initialization. +Prior to completion of this initialization sequence, the device returns +EBUSY to open() calls. EIO is returned for all open() failures. + +:: + + Management Partition Hypervisor + CRQ INIT + ----------------------------------------> + CRQ INIT COMPLETE + <---------------------------------------- + CAPABILITIES + ----------------------------------------> + CAPABILITIES RESPONSE + <---------------------------------------- + ADD BUFFER (HMC IDX=0,1,..) _ + <---------------------------------------- | + ADD BUFFER RESPONSE | - Perform # HMCs Iterations + ----------------------------------------> - + +VMC Interface Open +------------------ + +After the basic VMC channel has been initialized, an HMC session level +connection can be established. The application layer performs an open() to +the VMC device and executes an ioctl() against it, indicating the HMC ID +(32 bytes of data) for this session. If the VMC device is in an invalid +state, EIO will be returned for the ioctl(). The device driver creates a +new HMC session value (ranging from 1 to 255) and HMC index value (starting +at index 0 and ranging to 254) for this HMC ID. The driver then does an +RDMA of the HMC ID to the hypervisor, and then sends an Interface Open +message to the hypervisor to establish the session over the VMC. After the +hypervisor receives this information, it sends Add Buffer messages to the +management partition to seed an initial pool of buffers for the new HMC +connection. Finally, the hypervisor sends an Interface Open Response +message, to indicate that it is ready for normal runtime messaging. The +following illustrates this VMC flow: + +:: + + Management Partition Hypervisor + RDMA HMC ID + ----------------------------------------> + Interface Open + ----------------------------------------> + Add Buffer _ + <---------------------------------------- | + Add Buffer Response | - Perform N Iterations + ----------------------------------------> - + Interface Open Response + <---------------------------------------- + +VMC Interface Runtime +--------------------- + +During normal runtime, the management application and the hypervisor +exchange HMC messages via the Signal VMC message and RDMA operations. When +sending data to the hypervisor, the management application performs a +write() to the VMC device, and the driver RDMA’s the data to the hypervisor +and then sends a Signal Message. If a write() is attempted before VMC +device buffers have been made available by the hypervisor, or no buffers +are currently available, EBUSY is returned in response to the write(). A +write() will return EIO for all other errors, such as an invalid device +state. When the hypervisor sends a message to the management, the data is +put into a VMC buffer and an Signal Message is sent to the VMC driver in +the management partition. The driver RDMA’s the buffer into the partition +and passes the data up to the appropriate management application via a +read() to the VMC device. The read() request blocks if there is no buffer +available to read. The management application may use select() to wait for +the VMC device to become ready with data to read. + +:: + + Management Partition Hypervisor + MSG RDMA + ----------------------------------------> + SIGNAL MSG + ----------------------------------------> + SIGNAL MSG + <---------------------------------------- + MSG RDMA + <---------------------------------------- + +VMC Interface Close +------------------- + +HMC session level connections are closed by the management partition when +the application layer performs a close() against the device. This action +results in an Interface Close message flowing to the hypervisor, which +causes the session to be terminated. The device driver must free any +storage allocated for buffers for this HMC connection. + +:: + + Management Partition Hypervisor + INTERFACE CLOSE + ----------------------------------------> + INTERFACE CLOSE RESPONSE + <---------------------------------------- + +Additional Information +====================== + +For more information on the documentation for CRQ Messages, VMC Messages, +HMC interface Buffers, and signal messages please refer to the Linux on +Power Architecture Platform Reference. Section F. diff --git a/Documentation/networking/filter.txt b/Documentation/networking/filter.txt index a4508ec1816b..fd55c7de9991 100644 --- a/Documentation/networking/filter.txt +++ b/Documentation/networking/filter.txt @@ -169,7 +169,7 @@ access to BPF code as well. BPF engine and instruction set ------------------------------ -Under tools/net/ there's a small helper tool called bpf_asm which can +Under tools/bpf/ there's a small helper tool called bpf_asm which can be used to write low-level filters for example scenarios mentioned in the previous section. Asm-like syntax mentioned here has been implemented in bpf_asm and will be used for further explanations (instead of dealing with @@ -359,7 +359,7 @@ $ ./bpf_asm -c foo In particular, as usage with xt_bpf or cls_bpf can result in more complex BPF filters that might not be obvious at first, it's good to test filters before attaching to a live system. For that purpose, there's a small tool called -bpf_dbg under tools/net/ in the kernel source directory. This debugger allows +bpf_dbg under tools/bpf/ in the kernel source directory. This debugger allows for testing BPF filters against given pcap files, single stepping through the BPF code on the pcap's packets and to do BPF machine register dumps. @@ -483,7 +483,7 @@ Example output from dmesg: [ 3389.935851] JIT code: 00000030: 00 e8 28 94 ff e0 83 f8 01 75 07 b8 ff ff 00 00 [ 3389.935852] JIT code: 00000040: eb 02 31 c0 c9 c3 -In the kernel source tree under tools/net/, there's bpf_jit_disasm for +In the kernel source tree under tools/bpf/, there's bpf_jit_disasm for generating disassembly out of the kernel log's hexdump: # ./bpf_jit_disasm diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 5dc1a040a2f1..35ffaa281b26 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -1390,26 +1390,26 @@ mld_qrv - INTEGER Default: 2 (as specified by RFC3810 9.1) Minimum: 1 (as specified by RFC6636 4.5) -max_dst_opts_cnt - INTEGER +max_dst_opts_number - INTEGER Maximum number of non-padding TLVs allowed in a Destination options extension header. If this value is less than zero then unknown options are disallowed and the number of known TLVs allowed is the absolute value of this number. Default: 8 -max_hbh_opts_cnt - INTEGER +max_hbh_opts_number - INTEGER Maximum number of non-padding TLVs allowed in a Hop-by-Hop options extension header. If this value is less than zero then unknown options are disallowed and the number of known TLVs allowed is the absolute value of this number. Default: 8 -max dst_opts_len - INTEGER +max_dst_opts_length - INTEGER Maximum length allowed for a Destination options extension header. Default: INT_MAX (unlimited) -max hbh_opts_len - INTEGER +max_hbh_length - INTEGER Maximum length allowed for a Hop-by-Hop options extension header. Default: INT_MAX (unlimited) @@ -2126,18 +2126,3 @@ max_dgram_qlen - INTEGER Default: 10 - -UNDOCUMENTED: - -/proc/sys/net/irda/* - fast_poll_increase FIXME - warn_noreply_time FIXME - discovery_slots FIXME - slot_timeout FIXME - max_baud_rate FIXME - discovery_timeout FIXME - lap_keepalive_time FIXME - max_noreply_time FIXME - max_tx_data_size FIXME - max_tx_window FIXME - min_tx_turn_time FIXME diff --git a/Documentation/networking/ppp_generic.txt b/Documentation/networking/ppp_generic.txt index 091d20273dcb..61daf4b39600 100644 --- a/Documentation/networking/ppp_generic.txt +++ b/Documentation/networking/ppp_generic.txt @@ -300,12 +300,6 @@ unattached instance are: The ioctl calls available on an instance of /dev/ppp attached to a channel are: -* PPPIOCDETACH detaches the instance from the channel. This ioctl is - deprecated since the same effect can be achieved by closing the - instance. In order to prevent possible races this ioctl will fail - with an EINVAL error if more than one file descriptor refers to this - instance (i.e. as a result of dup(), dup2() or fork()). - * PPPIOCCONNECT connects this channel to a PPP interface. The argument should point to an int containing the interface unit number. It will return an EINVAL error if the channel is already diff --git a/Documentation/arm/CCN.txt b/Documentation/perf/arm-ccn.txt index 15cdb7bc57c3..15cdb7bc57c3 100644 --- a/Documentation/arm/CCN.txt +++ b/Documentation/perf/arm-ccn.txt diff --git a/Documentation/power/suspend-and-cpuhotplug.txt b/Documentation/power/suspend-and-cpuhotplug.txt index 31abd04b9572..6f55eb960a6d 100644 --- a/Documentation/power/suspend-and-cpuhotplug.txt +++ b/Documentation/power/suspend-and-cpuhotplug.txt @@ -168,7 +168,7 @@ update on the CPUs, as discussed below: [Please bear in mind that the kernel requests the microcode images from userspace, using the request_firmware() function defined in -drivers/base/firmware_class.c] +drivers/base/firmware_loader/main.c] a. When all the CPUs are identical: diff --git a/Documentation/process/2.Process.rst b/Documentation/process/2.Process.rst index ce5561bb3f8e..a9c46dd0706b 100644 --- a/Documentation/process/2.Process.rst +++ b/Documentation/process/2.Process.rst @@ -18,17 +18,17 @@ major kernel release happening every two or three months. The recent release history looks like this: ====== ================= - 2.6.38 March 14, 2011 - 2.6.37 January 4, 2011 - 2.6.36 October 20, 2010 - 2.6.35 August 1, 2010 - 2.6.34 May 15, 2010 - 2.6.33 February 24, 2010 + 4.11 April 30, 2017 + 4.12 July 2, 2017 + 4.13 September 3, 2017 + 4.14 November 12, 2017 + 4.15 January 28, 2018 + 4.16 April 1, 2018 ====== ================= -Every 2.6.x release is a major kernel release with new features, internal -API changes, and more. A typical 2.6 release can contain nearly 10,000 -changesets with changes to several hundred thousand lines of code. 2.6 is +Every 4.x release is a major kernel release with new features, internal +API changes, and more. A typical 4.x release contain about 13,000 +changesets with changes to several hundred thousand lines of code. 4.x is thus the leading edge of Linux kernel development; the kernel uses a rolling development model which is continually integrating major changes. @@ -70,20 +70,19 @@ will get up to somewhere between -rc6 and -rc9 before the kernel is considered to be sufficiently stable and the final 2.6.x release is made. At that point the whole process starts over again. -As an example, here is how the 2.6.38 development cycle went (all dates in -2011): +As an example, here is how the 4.16 development cycle went (all dates in +2018): ============== =============================== - January 4 2.6.37 stable release - January 18 2.6.38-rc1, merge window closes - January 21 2.6.38-rc2 - February 1 2.6.38-rc3 - February 7 2.6.38-rc4 - February 15 2.6.38-rc5 - February 21 2.6.38-rc6 - March 1 2.6.38-rc7 - March 7 2.6.38-rc8 - March 14 2.6.38 stable release + January 28 4.15 stable release + February 11 4.16-rc1, merge window closes + February 18 4.16-rc2 + February 25 4.16-rc3 + March 4 4.16-rc4 + March 11 4.16-rc5 + March 18 4.16-rc6 + March 25 4.16-rc7 + April 1 4.17 stable release ============== =============================== How do the developers decide when to close the development cycle and create @@ -99,37 +98,42 @@ release is made. In the real world, this kind of perfection is hard to achieve; there are just too many variables in a project of this size. There comes a point where delaying the final release just makes the problem worse; the pile of changes waiting for the next merge window will grow -larger, creating even more regressions the next time around. So most 2.6.x +larger, creating even more regressions the next time around. So most 4.x kernels go out with a handful of known regressions though, hopefully, none of them are serious. Once a stable release is made, its ongoing maintenance is passed off to the "stable team," currently consisting of Greg Kroah-Hartman. The stable team -will release occasional updates to the stable release using the 2.6.x.y +will release occasional updates to the stable release using the 4.x.y numbering scheme. To be considered for an update release, a patch must (1) fix a significant bug, and (2) already be merged into the mainline for the next development kernel. Kernels will typically receive stable updates for a little more than one development cycle past their initial release. So, -for example, the 2.6.36 kernel's history looked like: +for example, the 4.13 kernel's history looked like: ============== =============================== - October 10 2.6.36 stable release - November 22 2.6.36.1 - December 9 2.6.36.2 - January 7 2.6.36.3 - February 17 2.6.36.4 + September 3 4.13 stable release + September 13 4.13.1 + September 20 4.13.2 + September 27 4.13.3 + October 5 4.13.4 + October 12 4.13.5 + ... ... + November 24 4.13.16 ============== =============================== -2.6.36.4 was the final stable update for the 2.6.36 release. +4.13.16 was the final stable update of the 4.13 release. Some kernels are designated "long term" kernels; they will receive support for a longer period. As of this writing, the current long term kernels and their maintainers are: - ====== ====================== =========================== - 2.6.27 Willy Tarreau (Deep-frozen stable kernel) - 2.6.32 Greg Kroah-Hartman - 2.6.35 Andi Kleen (Embedded flag kernel) + ====== ====================== ============================== + 3.16 Ben Hutchings (very long-term stable kernel) + 4.1 Sasha Levin + 4.4 Greg Kroah-Hartman (very long-term stable kernel) + 4.9 Greg Kroah-Hartman + 4.14 Greg Kroah-Hartman ====== ====================== =========================== The selection of a kernel for long-term support is purely a matter of a diff --git a/Documentation/process/4.Coding.rst b/Documentation/process/4.Coding.rst index 26b106071364..eb4b185d168c 100644 --- a/Documentation/process/4.Coding.rst +++ b/Documentation/process/4.Coding.rst @@ -58,6 +58,14 @@ can never be transgressed. If there is a good reason to go against the style (a line which becomes far less readable if split to fit within the 80-column limit, for example), just do it. +Note that you can also use the ``clang-format`` tool to help you with +these rules, to quickly re-format parts of your code automatically, +and to review full files in order to spot coding style mistakes, +typos and possible improvements. It is also handy for sorting ``#includes``, +for aligning variables/macros, for reflowing text and other similar tasks. +See the file :ref:`Documentation/process/clang-format.rst <clangformat>` +for more details. + Abstraction layers ****************** diff --git a/Documentation/process/5.Posting.rst b/Documentation/process/5.Posting.rst index c209d70da66f..c418c5d6cae4 100644 --- a/Documentation/process/5.Posting.rst +++ b/Documentation/process/5.Posting.rst @@ -10,8 +10,8 @@ of conventions and procedures which are used in the posting of patches; following them will make life much easier for everybody involved. This document will attempt to cover these expectations in reasonable detail; more information can also be found in the files process/submitting-patches.rst, -process/submitting-drivers.rst, and process/submit-checklist.rst in the kernel documentation -directory. +process/submitting-drivers.rst, and process/submit-checklist.rst in the kernel +documentation directory. When to post @@ -198,8 +198,8 @@ pass it to diff with the "-X" option. The tags mentioned above are used to describe how various developers have been associated with the development of this patch. They are described in -detail in the process/submitting-patches.rst document; what follows here is a brief -summary. Each of these lines has the format: +detail in the process/submitting-patches.rst document; what follows here is a +brief summary. Each of these lines has the format: :: @@ -210,8 +210,8 @@ The tags in common use are: - Signed-off-by: this is a developer's certification that he or she has the right to submit the patch for inclusion into the kernel. It is an agreement to the Developer's Certificate of Origin, the full text of - which can be found in Documentation/process/submitting-patches.rst. Code without a - proper signoff cannot be merged into the mainline. + which can be found in Documentation/process/submitting-patches.rst. Code + without a proper signoff cannot be merged into the mainline. - Co-developed-by: states that the patch was also created by another developer along with the original author. This is useful at times when multiple @@ -226,8 +226,8 @@ The tags in common use are: it to work. - Reviewed-by: the named developer has reviewed the patch for correctness; - see the reviewer's statement in Documentation/process/submitting-patches.rst for more - detail. + see the reviewer's statement in Documentation/process/submitting-patches.rst + for more detail. - Reported-by: names a user who reported a problem which is fixed by this patch; this tag is used to give credit to the (often underappreciated) diff --git a/Documentation/process/adding-syscalls.rst b/Documentation/process/adding-syscalls.rst index 314c8bf6f2a2..0d4f29bc798b 100644 --- a/Documentation/process/adding-syscalls.rst +++ b/Documentation/process/adding-syscalls.rst @@ -360,7 +360,7 @@ First, the entry in ``arch/x86/entry/syscalls/syscall_32.tbl`` gets an extra column to indicate that a 32-bit userspace program running on a 64-bit kernel should hit the compat entry point:: - 380 i386 xyzzy sys_xyzzy compat_sys_xyzzy + 380 i386 xyzzy sys_xyzzy __ia32_compat_sys_xyzzy Second, you need to figure out what should happen for the x32 ABI version of the new system call. There's a choice here: the layout of the arguments @@ -373,7 +373,7 @@ the compatibility wrapper:: 333 64 xyzzy sys_xyzzy ... - 555 x32 xyzzy compat_sys_xyzzy + 555 x32 xyzzy __x32_compat_sys_xyzzy If no pointers are involved, then it is preferable to re-use the 64-bit system call for the x32 ABI (and consequently the entry in diff --git a/Documentation/process/clang-format.rst b/Documentation/process/clang-format.rst new file mode 100644 index 000000000000..6710c0707721 --- /dev/null +++ b/Documentation/process/clang-format.rst @@ -0,0 +1,184 @@ +.. _clangformat: + +clang-format +============ + +``clang-format`` is a tool to format C/C++/... code according to +a set of rules and heuristics. Like most tools, it is not perfect +nor covers every single case, but it is good enough to be helpful. + +``clang-format`` can be used for several purposes: + + - Quickly reformat a block of code to the kernel style. Specially useful + when moving code around and aligning/sorting. See clangformatreformat_. + + - Spot style mistakes, typos and possible improvements in files + you maintain, patches you review, diffs, etc. See clangformatreview_. + + - Help you follow the coding style rules, specially useful for those + new to kernel development or working at the same time in several + projects with different coding styles. + +Its configuration file is ``.clang-format`` in the root of the kernel tree. +The rules contained there try to approximate the most common kernel +coding style. They also try to follow :ref:`Documentation/process/coding-style.rst <codingstyle>` +as much as possible. Since not all the kernel follows the same style, +it is possible that you may want to tweak the defaults for a particular +subsystem or folder. To do so, you can override the defaults by writing +another ``.clang-format`` file in a subfolder. + +The tool itself has already been included in the repositories of popular +Linux distributions for a long time. Search for ``clang-format`` in +your repositories. Otherwise, you can either download pre-built +LLVM/clang binaries or build the source code from: + + http://releases.llvm.org/download.html + +See more information about the tool at: + + https://clang.llvm.org/docs/ClangFormat.html + + https://clang.llvm.org/docs/ClangFormatStyleOptions.html + + +.. _clangformatreview: + +Review files and patches for coding style +----------------------------------------- + +By running the tool in its inline mode, you can review full subsystems, +folders or individual files for code style mistakes, typos or improvements. + +To do so, you can run something like:: + + # Make sure your working directory is clean! + clang-format -i kernel/*.[ch] + +And then take a look at the git diff. + +Counting the lines of such a diff is also useful for improving/tweaking +the style options in the configuration file; as well as testing new +``clang-format`` features/versions. + +``clang-format`` also supports reading unified diffs, so you can review +patches and git diffs easily. See the documentation at: + + https://clang.llvm.org/docs/ClangFormat.html#script-for-patch-reformatting + +To avoid ``clang-format`` formatting some portion of a file, you can do:: + + int formatted_code; + // clang-format off + void unformatted_code ; + // clang-format on + void formatted_code_again; + +While it might be tempting to use this to keep a file always in sync with +``clang-format``, specially if you are writing new files or if you are +a maintainer, please note that people might be running different +``clang-format`` versions or not have it available at all. Therefore, +you should probably refrain yourself from using this in kernel sources; +at least until we see if ``clang-format`` becomes commonplace. + + +.. _clangformatreformat: + +Reformatting blocks of code +--------------------------- + +By using an integration with your text editor, you can reformat arbitrary +blocks (selections) of code with a single keystroke. This is specially +useful when moving code around, for complex code that is deeply intended, +for multi-line macros (and aligning their backslashes), etc. + +Remember that you can always tweak the changes afterwards in those cases +where the tool did not do an optimal job. But as a first approximation, +it can be very useful. + +There are integrations for many popular text editors. For some of them, +like vim, emacs, BBEdit and Visual Studio you can find support built-in. +For instructions, read the appropiate section at: + + https://clang.llvm.org/docs/ClangFormat.html + +For Atom, Eclipse, Sublime Text, Visual Studio Code, XCode and other +editors and IDEs you should be able to find ready-to-use plugins. + +For this use case, consider using a secondary ``.clang-format`` +so that you can tweak a few options. See clangformatextra_. + + +.. _clangformatmissing: + +Missing support +--------------- + +``clang-format`` is missing support for some things that are common +in kernel code. They are easy to remember, so if you use the tool +regularly, you will quickly learn to avoid/ignore those. + +In particular, some very common ones you will notice are: + + - Aligned blocks of one-line ``#defines``, e.g.:: + + #define TRACING_MAP_BITS_DEFAULT 11 + #define TRACING_MAP_BITS_MAX 17 + #define TRACING_MAP_BITS_MIN 7 + + vs.:: + + #define TRACING_MAP_BITS_DEFAULT 11 + #define TRACING_MAP_BITS_MAX 17 + #define TRACING_MAP_BITS_MIN 7 + + - Aligned designated initializers, e.g.:: + + static const struct file_operations uprobe_events_ops = { + .owner = THIS_MODULE, + .open = probes_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, + .write = probes_write, + }; + + vs.:: + + static const struct file_operations uprobe_events_ops = { + .owner = THIS_MODULE, + .open = probes_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, + .write = probes_write, + }; + + +.. _clangformatextra: + +Extra features/options +---------------------- + +Some features/style options are not enabled by default in the configuration +file in order to minimize the differences between the output and the current +code. In other words, to make the difference as small as possible, +which makes reviewing full-file style, as well diffs and patches as easy +as possible. + +In other cases (e.g. particular subsystems/folders/files), the kernel style +might be different and enabling some of these options may approximate +better the style there. + +For instance: + + - Aligning assignments (``AlignConsecutiveAssignments``). + + - Aligning declarations (``AlignConsecutiveDeclarations``). + + - Reflowing text in comments (``ReflowComments``). + + - Sorting ``#includes`` (``SortIncludes``). + +They are typically useful for block re-formatting, rather than full-file. +You might want to create another ``.clang-format`` file and use that one +from your editor/IDE instead. diff --git a/Documentation/process/coding-style.rst b/Documentation/process/coding-style.rst index d98deb62c400..4e7c0a1c427a 100644 --- a/Documentation/process/coding-style.rst +++ b/Documentation/process/coding-style.rst @@ -631,6 +631,14 @@ options ``-kr -i8`` (stands for ``K&R, 8 character indents``), or use re-formatting you may want to take a look at the man page. But remember: ``indent`` is not a fix for bad programming. +Note that you can also use the ``clang-format`` tool to help you with +these rules, to quickly re-format parts of your code automatically, +and to review full files in order to spot coding style mistakes, +typos and possible improvements. It is also handy for sorting ``#includes``, +for aligning variables/macros, for reflowing text and other similar tasks. +See the file :ref:`Documentation/process/clang-format.rst <clangformat>` +for more details. + 10) Kconfig configuration files ------------------------------- diff --git a/Documentation/process/index.rst b/Documentation/process/index.rst index 1c9fe657ed01..37bd0628b6ee 100644 --- a/Documentation/process/index.rst +++ b/Documentation/process/index.rst @@ -52,6 +52,7 @@ lack of a better place. adding-syscalls magic-number volatile-considered-harmful + clang-format .. only:: subproject and html diff --git a/Documentation/process/magic-number.rst b/Documentation/process/magic-number.rst index 00cecf1fcba9..633be1043690 100644 --- a/Documentation/process/magic-number.rst +++ b/Documentation/process/magic-number.rst @@ -157,8 +157,5 @@ memory management. See ``include/sound/sndmagic.h`` for complete list of them. M OSS sound drivers have their magic numbers constructed from the soundcard PCI ID - these are not listed here as well. -IrDA subsystem also uses large number of own magic numbers, see -``include/net/irda/irda.h`` for a complete list of them. - HFS is another larger user of magic numbers - you can find them in ``fs/hfs/hfs.h``. diff --git a/Documentation/process/maintainer-pgp-guide.rst b/Documentation/process/maintainer-pgp-guide.rst index b453561a7148..aff9b1a4d77b 100644 --- a/Documentation/process/maintainer-pgp-guide.rst +++ b/Documentation/process/maintainer-pgp-guide.rst @@ -219,7 +219,7 @@ Our goal is to protect your master key by moving it to offline media, so if you only have a combined **[SC]** key, then you should create a separate signing subkey:: - $ gpg --quick-add-key [fpr] ed25519 sign + $ gpg --quick-addkey [fpr] ed25519 sign Remember to tell the keyservers about this change, so others can pull down your new subkey:: @@ -450,11 +450,18 @@ functionality. There are several options available: others. If you want to use ECC keys, your best bet among commercially available devices is the Nitrokey Start. +.. note:: + + If you are listed in MAINTAINERS or have an account at kernel.org, + you `qualify for a free Nitrokey Start`_ courtesy of The Linux + Foundation. + .. _`Nitrokey Start`: https://shop.nitrokey.com/shop/product/nitrokey-start-6 .. _`Nitrokey Pro`: https://shop.nitrokey.com/shop/product/nitrokey-pro-3 .. _`Yubikey 4`: https://www.yubico.com/product/yubikey-4-series/ .. _Gnuk: http://www.fsij.org/doc-gnuk/ .. _`LWN has a good review`: https://lwn.net/Articles/736231/ +.. _`qualify for a free Nitrokey Start`: https://www.kernel.org/nitrokey-digital-tokens-for-kernel-developers.html Configure your smartcard device ------------------------------- @@ -482,7 +489,7 @@ there are no convenient command-line switches:: You should set the user PIN (1), Admin PIN (3), and the Reset Code (4). Please make sure to record and store these in a safe place -- especially the Admin PIN and the Reset Code (which allows you to completely wipe -the smartcard). You so rarely need to use the Admin PIN, that you will +the smartcard). You so rarely need to use the Admin PIN, that you will inevitably forget what it is if you do not record it. Getting back to the main card menu, you can also set other values (such @@ -494,6 +501,12 @@ additionally leak information about your smartcard should you lose it. Despite having the name "PIN", neither the user PIN nor the admin PIN on the card need to be numbers. +.. warning:: + + Some devices may require that you move the subkeys onto the device + before you can change the passphrase. Please check the documentation + provided by the device manufacturer. + Move the subkeys to your smartcard ---------------------------------- @@ -655,6 +668,20 @@ want to import these changes back into your regular working directory:: $ gpg --export | gpg --homedir ~/.gnupg --import $ unset GNUPGHOME +Using gpg-agent over ssh +~~~~~~~~~~~~~~~~~~~~~~~~ + +You can forward your gpg-agent over ssh if you need to sign tags or +commits on a remote system. Please refer to the instructions provided +on the GnuPG wiki: + +- `Agent Forwarding over SSH`_ + +It works more smoothly if you can modify the sshd server settings on the +remote end. + +.. _`Agent Forwarding over SSH`: https://wiki.gnupg.org/AgentForwarding + Using PGP with Git ================== @@ -692,6 +719,7 @@ should be used (``[fpr]`` is the fingerprint of your key):: tell git to always use it instead of the legacy ``gpg`` from version 1:: $ git config --global gpg.program gpg2 + $ git config --global gpgv.program gpgv2 How to work with signed tags ---------------------------- @@ -731,6 +759,13 @@ If you are verifying someone else's git tag, then you will need to import their PGP key. Please refer to the ":ref:`verify_identities`" section below. +.. note:: + + If you get "``gpg: Can't check signature: unknown pubkey + algorithm``" error, you need to tell git to use gpgv2 for + verification, so it properly processes signatures made by ECC keys. + See instructions at the start of this section. + Configure git to always sign annotated tags ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ diff --git a/Documentation/process/submitting-patches.rst b/Documentation/process/submitting-patches.rst index f7152ed565e5..908bb55be407 100644 --- a/Documentation/process/submitting-patches.rst +++ b/Documentation/process/submitting-patches.rst @@ -761,7 +761,7 @@ requests, especially from new, unknown developers. If in doubt you can use the pull request as the cover letter for a normal posting of the patch series, giving the maintainer the option of using either. -A pull request should have [GIT] or [PULL] in the subject line. The +A pull request should have [GIT PULL] in the subject line. The request itself should include the repository name and the branch of interest on a single line; it should look something like:: diff --git a/Documentation/s390/vfio-ccw.txt b/Documentation/s390/vfio-ccw.txt index 90b3dfead81b..2be11ad864ff 100644 --- a/Documentation/s390/vfio-ccw.txt +++ b/Documentation/s390/vfio-ccw.txt @@ -28,7 +28,7 @@ every detail. More information/reference could be found here: https://en.wikipedia.org/wiki/Channel_I/O - s390 architecture: s390 Principles of Operation manual (IBM Form. No. SA22-7832) -- The existing Qemu code which implements a simple emulated channel +- The existing QEMU code which implements a simple emulated channel subsystem could also be a good reference. It makes it easier to follow the flow. qemu/hw/s390x/css.c @@ -39,22 +39,22 @@ For vfio mediated device framework: Motivation of vfio-ccw ---------------------- -Currently, a guest virtualized via qemu/kvm on s390 only sees +Typically, a guest virtualized via QEMU/KVM on s390 only sees paravirtualized virtio devices via the "Virtio Over Channel I/O (virtio-ccw)" transport. This makes virtio devices discoverable via standard operating system algorithms for handling channel devices. However this is not enough. On s390 for the majority of devices, which use the standard Channel I/O based mechanism, we also need to provide -the functionality of passing through them to a Qemu virtual machine. +the functionality of passing through them to a QEMU virtual machine. This includes devices that don't have a virtio counterpart (e.g. tape drives) or that have specific characteristics which guests want to exploit. For passing a device to a guest, we want to use the same interface as -everybody else, namely vfio. Thus, we would like to introduce vfio -support for channel devices. And we would like to name this new vfio -device "vfio-ccw". +everybody else, namely vfio. We implement this vfio support for channel +devices via the vfio mediated device framework and the subchannel device +driver "vfio_ccw". Access patterns of CCW devices ------------------------------ @@ -99,7 +99,7 @@ As mentioned above, we realize vfio-ccw with a mdev implementation. Channel I/O does not have IOMMU hardware support, so the physical vfio-ccw device does not have an IOMMU level translation or isolation. -Sub-channel I/O instructions are all privileged instructions, When +Subchannel I/O instructions are all privileged instructions. When handling the I/O instruction interception, vfio-ccw has the software policing and translation how the channel program is programmed before it gets sent to hardware. @@ -121,7 +121,7 @@ devices: - The vfio_mdev driver for the mediated vfio ccw device. This is provided by the mdev framework. It is a vfio device driver for the mdev that created by vfio_ccw. - It realize a group of vfio device driver callbacks, adds itself to a + It realizes a group of vfio device driver callbacks, adds itself to a vfio group, and registers itself to the mdev framework as a mdev driver. It uses a vfio iommu backend that uses the existing map and unmap @@ -178,7 +178,7 @@ vfio-ccw I/O region An I/O region is used to accept channel program request from user space and store I/O interrupt result for user space to retrieve. The -defination of the region is: +definition of the region is: struct ccw_io_region { #define ORB_AREA_SIZE 12 @@ -198,30 +198,23 @@ irb_area stores the I/O result. ret_code stores a return code for each access of the region. -vfio-ccw patches overview -------------------------- +vfio-ccw operation details +-------------------------- -For now, our patches are rebased on the latest mdev implementation. -vfio-ccw follows what vfio-pci did on the s390 paltform and uses -vfio-iommu-type1 as the vfio iommu backend. It's a good start to launch -the code review for vfio-ccw. Note that the implementation is far from -complete yet; but we'd like to get feedback for the general -architecture. +vfio-ccw follows what vfio-pci did on the s390 platform and uses +vfio-iommu-type1 as the vfio iommu backend. * CCW translation APIs -- Description: - These introduce a group of APIs (start with 'cp_') to do CCW - translation. The CCWs passed in by a user space program are - organized with their guest physical memory addresses. These APIs - will copy the CCWs into the kernel space, and assemble a runnable - kernel channel program by updating the guest physical addresses with - their corresponding host physical addresses. -- Patches: - vfio: ccw: introduce channel program interfaces + A group of APIs (start with 'cp_') to do CCW translation. The CCWs + passed in by a user space program are organized with their guest + physical memory addresses. These APIs will copy the CCWs into kernel + space, and assemble a runnable kernel channel program by updating the + guest physical addresses with their corresponding host physical addresses. + Note that we have to use IDALs even for direct-access CCWs, as the + referenced memory can be located anywhere, including above 2G. * vfio_ccw device driver -- Description: - The following patches utilizes the CCW translation APIs and introduce + This driver utilizes the CCW translation APIs and introduces vfio_ccw, which is the driver for the I/O subchannel devices you want to pass through. vfio_ccw implements the following vfio ioctls: @@ -236,20 +229,14 @@ architecture. This also provides the SET_IRQ ioctl to setup an event notifier to notify the user space program the I/O completion in an asynchronous way. -- Patches: - vfio: ccw: basic implementation for vfio_ccw driver - vfio: ccw: introduce ccw_io_region - vfio: ccw: realize VFIO_DEVICE_GET_REGION_INFO ioctl - vfio: ccw: realize VFIO_DEVICE_RESET ioctl - vfio: ccw: realize VFIO_DEVICE_G(S)ET_IRQ_INFO ioctls - -The user of vfio-ccw is not limited to Qemu, while Qemu is definitely a + +The use of vfio-ccw is not limited to QEMU, while QEMU is definitely a good example to get understand how these patches work. Here is a little -bit more detail how an I/O request triggered by the Qemu guest will be +bit more detail how an I/O request triggered by the QEMU guest will be handled (without error handling). Explanation: -Q1-Q7: Qemu side process. +Q1-Q7: QEMU side process. K1-K5: Kernel side process. Q1. Get I/O region info during initialization. @@ -263,7 +250,7 @@ Q4. Write the guest channel program and ORB to the I/O region. K2. Translate the guest channel program to a host kernel space channel program, which becomes runnable for a real device. K3. With the necessary information contained in the orb passed in - by Qemu, issue the ccwchain to the device. + by QEMU, issue the ccwchain to the device. K4. Return the ssch CC code. Q5. Return the CC code to the guest. @@ -271,7 +258,7 @@ Q5. Return the CC code to the guest. K5. Interrupt handler gets the I/O result and write the result to the I/O region. - K6. Signal Qemu to retrieve the result. + K6. Signal QEMU to retrieve the result. Q6. Get the signal and event handler reads out the result from the I/O region. Q7. Update the irb for the guest. @@ -289,10 +276,20 @@ More information for DASD and ECKD could be found here: https://en.wikipedia.org/wiki/Direct-access_storage_device https://en.wikipedia.org/wiki/Count_key_data -Together with the corresponding work in Qemu, we can bring the passed +Together with the corresponding work in QEMU, we can bring the passed through DASD/ECKD device online in a guest now and use it as a block device. +While the current code allows the guest to start channel programs via +START SUBCHANNEL, support for HALT SUBCHANNEL or CLEAR SUBCHANNEL is +not yet implemented. + +vfio-ccw supports classic (command mode) channel I/O only. Transport +mode (HPF) is not supported. + +QDIO subchannels are currently not supported. Classic devices other than +DASD/ECKD might work, but have not been tested. + Reference --------- 1. ESA/s390 Principles of Operation manual (IBM Form. No. SA22-7832) diff --git a/Documentation/scheduler/sched-deadline.txt b/Documentation/scheduler/sched-deadline.txt index 8ce78f82ae23..b14e03ff3528 100644 --- a/Documentation/scheduler/sched-deadline.txt +++ b/Documentation/scheduler/sched-deadline.txt @@ -49,7 +49,7 @@ CONTENTS 2.1 Main algorithm ------------------ - SCHED_DEADLINE uses three parameters, named "runtime", "period", and + SCHED_DEADLINE [18] uses three parameters, named "runtime", "period", and "deadline", to schedule tasks. A SCHED_DEADLINE task should receive "runtime" microseconds of execution time every "period" microseconds, and these "runtime" microseconds are available within "deadline" microseconds @@ -117,6 +117,10 @@ CONTENTS scheduling deadline = scheduling deadline + period remaining runtime = remaining runtime + runtime + The SCHED_FLAG_DL_OVERRUN flag in sched_attr's sched_flags field allows a task + to get informed about runtime overruns through the delivery of SIGXCPU + signals. + 2.2 Bandwidth reclaiming ------------------------ @@ -279,6 +283,19 @@ CONTENTS running_bw is incremented. +2.3 Energy-aware scheduling +------------------------ + + When cpufreq's schedutil governor is selected, SCHED_DEADLINE implements the + GRUB-PA [19] algorithm, reducing the CPU operating frequency to the minimum + value that still allows to meet the deadlines. This behavior is currently + implemented only for ARM architectures. + + A particular care must be taken in case the time needed for changing frequency + is of the same order of magnitude of the reservation period. In such cases, + setting a fixed CPU frequency results in a lower amount of deadline misses. + + 3. Scheduling Real-Time Tasks ============================= @@ -505,6 +522,12 @@ CONTENTS 17 - L. Abeni, G. Lipari, A. Parri, Y. Sun, Multicore CPU reclaiming: parallel or sequential?. In Proceedings of the 31st Annual ACM Symposium on Applied Computing, 2016. + 18 - J. Lelli, C. Scordino, L. Abeni, D. Faggioli, Deadline scheduling in the + Linux kernel, Software: Practice and Experience, 46(6): 821-839, June + 2016. + 19 - C. Scordino, L. Abeni, J. Lelli, Energy-Aware Real-Time Scheduling in + the Linux Kernel, 33rd ACM/SIGAPP Symposium On Applied Computing (SAC + 2018), Pau, France, April 2018. 4. Bandwidth management diff --git a/Documentation/scsi/scsi_eh.txt b/Documentation/scsi/scsi_eh.txt index 11e447bdb3a5..1b7436932a2b 100644 --- a/Documentation/scsi/scsi_eh.txt +++ b/Documentation/scsi/scsi_eh.txt @@ -82,24 +82,13 @@ function 1. invokes optional hostt->eh_timed_out() callback. Return value can be one of - - BLK_EH_HANDLED - This indicates that eh_timed_out() dealt with the timeout. - The command is passed back to the block layer and completed - via __blk_complete_requests(). - - *NOTE* After returning BLK_EH_HANDLED the SCSI layer is - assumed to be finished with the command, and no other - functions from the SCSI layer will be called. So this - should typically only be returned if the eh_timed_out() - handler raced with normal completion. - - BLK_EH_RESET_TIMER This indicates that more time is required to finish the command. Timer is restarted. This action is counted as a retry and only allowed scmd->allowed + 1(!) times. Once the - limit is reached, action for BLK_EH_NOT_HANDLED is taken instead. + limit is reached, action for BLK_EH_DONE is taken instead. - - BLK_EH_NOT_HANDLED + - BLK_EH_DONE eh_timed_out() callback did not handle the command. Step #2 is taken. diff --git a/Documentation/security/LSM-sctp.rst b/Documentation/security/LSM-sctp.rst new file mode 100644 index 000000000000..6e5a3925a860 --- /dev/null +++ b/Documentation/security/LSM-sctp.rst @@ -0,0 +1,175 @@ +SCTP LSM Support +================ + +For security module support, three SCTP specific hooks have been implemented:: + + security_sctp_assoc_request() + security_sctp_bind_connect() + security_sctp_sk_clone() + +Also the following security hook has been utilised:: + + security_inet_conn_established() + +The usage of these hooks are described below with the SELinux implementation +described in ``Documentation/security/SELinux-sctp.rst`` + + +security_sctp_assoc_request() +----------------------------- +Passes the ``@ep`` and ``@chunk->skb`` of the association INIT packet to the +security module. Returns 0 on success, error on failure. +:: + + @ep - pointer to sctp endpoint structure. + @skb - pointer to skbuff of association packet. + + +security_sctp_bind_connect() +----------------------------- +Passes one or more ipv4/ipv6 addresses to the security module for validation +based on the ``@optname`` that will result in either a bind or connect +service as shown in the permission check tables below. +Returns 0 on success, error on failure. +:: + + @sk - Pointer to sock structure. + @optname - Name of the option to validate. + @address - One or more ipv4 / ipv6 addresses. + @addrlen - The total length of address(s). This is calculated on each + ipv4 or ipv6 address using sizeof(struct sockaddr_in) or + sizeof(struct sockaddr_in6). + + ------------------------------------------------------------------ + | BIND Type Checks | + | @optname | @address contains | + |----------------------------|-----------------------------------| + | SCTP_SOCKOPT_BINDX_ADD | One or more ipv4 / ipv6 addresses | + | SCTP_PRIMARY_ADDR | Single ipv4 or ipv6 address | + | SCTP_SET_PEER_PRIMARY_ADDR | Single ipv4 or ipv6 address | + ------------------------------------------------------------------ + + ------------------------------------------------------------------ + | CONNECT Type Checks | + | @optname | @address contains | + |----------------------------|-----------------------------------| + | SCTP_SOCKOPT_CONNECTX | One or more ipv4 / ipv6 addresses | + | SCTP_PARAM_ADD_IP | One or more ipv4 / ipv6 addresses | + | SCTP_SENDMSG_CONNECT | Single ipv4 or ipv6 address | + | SCTP_PARAM_SET_PRIMARY | Single ipv4 or ipv6 address | + ------------------------------------------------------------------ + +A summary of the ``@optname`` entries is as follows:: + + SCTP_SOCKOPT_BINDX_ADD - Allows additional bind addresses to be + associated after (optionally) calling + bind(3). + sctp_bindx(3) adds a set of bind + addresses on a socket. + + SCTP_SOCKOPT_CONNECTX - Allows the allocation of multiple + addresses for reaching a peer + (multi-homed). + sctp_connectx(3) initiates a connection + on an SCTP socket using multiple + destination addresses. + + SCTP_SENDMSG_CONNECT - Initiate a connection that is generated by a + sendmsg(2) or sctp_sendmsg(3) on a new asociation. + + SCTP_PRIMARY_ADDR - Set local primary address. + + SCTP_SET_PEER_PRIMARY_ADDR - Request peer sets address as + association primary. + + SCTP_PARAM_ADD_IP - These are used when Dynamic Address + SCTP_PARAM_SET_PRIMARY - Reconfiguration is enabled as explained below. + + +To support Dynamic Address Reconfiguration the following parameters must be +enabled on both endpoints (or use the appropriate **setsockopt**\(2)):: + + /proc/sys/net/sctp/addip_enable + /proc/sys/net/sctp/addip_noauth_enable + +then the following *_PARAM_*'s are sent to the peer in an +ASCONF chunk when the corresponding ``@optname``'s are present:: + + @optname ASCONF Parameter + ---------- ------------------ + SCTP_SOCKOPT_BINDX_ADD -> SCTP_PARAM_ADD_IP + SCTP_SET_PEER_PRIMARY_ADDR -> SCTP_PARAM_SET_PRIMARY + + +security_sctp_sk_clone() +------------------------- +Called whenever a new socket is created by **accept**\(2) +(i.e. a TCP style socket) or when a socket is 'peeled off' e.g userspace +calls **sctp_peeloff**\(3). +:: + + @ep - pointer to current sctp endpoint structure. + @sk - pointer to current sock structure. + @sk - pointer to new sock structure. + + +security_inet_conn_established() +--------------------------------- +Called when a COOKIE ACK is received:: + + @sk - pointer to sock structure. + @skb - pointer to skbuff of the COOKIE ACK packet. + + +Security Hooks used for Association Establishment +================================================= +The following diagram shows the use of ``security_sctp_bind_connect()``, +``security_sctp_assoc_request()``, ``security_inet_conn_established()`` when +establishing an association. +:: + + SCTP endpoint "A" SCTP endpoint "Z" + ================= ================= + sctp_sf_do_prm_asoc() + Association setup can be initiated + by a connect(2), sctp_connectx(3), + sendmsg(2) or sctp_sendmsg(3). + These will result in a call to + security_sctp_bind_connect() to + initiate an association to + SCTP peer endpoint "Z". + INIT ---------------------------------------------> + sctp_sf_do_5_1B_init() + Respond to an INIT chunk. + SCTP peer endpoint "A" is + asking for an association. Call + security_sctp_assoc_request() + to set the peer label if first + association. + If not first association, check + whether allowed, IF so send: + <----------------------------------------------- INIT ACK + | ELSE audit event and silently + | discard the packet. + | + COOKIE ECHO ------------------------------------------> + | + | + | + <------------------------------------------- COOKIE ACK + | | + sctp_sf_do_5_1E_ca | + Call security_inet_conn_established() | + to set the peer label. | + | | + | If SCTP_SOCKET_TCP or peeled off + | socket security_sctp_sk_clone() is + | called to clone the new socket. + | | + ESTABLISHED ESTABLISHED + | | + ------------------------------------------------------------------ + | Association Established | + ------------------------------------------------------------------ + + diff --git a/Documentation/security/SELinux-sctp.rst b/Documentation/security/SELinux-sctp.rst new file mode 100644 index 000000000000..a332cb1c5334 --- /dev/null +++ b/Documentation/security/SELinux-sctp.rst @@ -0,0 +1,158 @@ +SCTP SELinux Support +===================== + +Security Hooks +=============== + +``Documentation/security/LSM-sctp.rst`` describes the following SCTP security +hooks with the SELinux specifics expanded below:: + + security_sctp_assoc_request() + security_sctp_bind_connect() + security_sctp_sk_clone() + security_inet_conn_established() + + +security_sctp_assoc_request() +----------------------------- +Passes the ``@ep`` and ``@chunk->skb`` of the association INIT packet to the +security module. Returns 0 on success, error on failure. +:: + + @ep - pointer to sctp endpoint structure. + @skb - pointer to skbuff of association packet. + +The security module performs the following operations: + IF this is the first association on ``@ep->base.sk``, then set the peer + sid to that in ``@skb``. This will ensure there is only one peer sid + assigned to ``@ep->base.sk`` that may support multiple associations. + + ELSE validate the ``@ep->base.sk peer_sid`` against the ``@skb peer sid`` + to determine whether the association should be allowed or denied. + + Set the sctp ``@ep sid`` to socket's sid (from ``ep->base.sk``) with + MLS portion taken from ``@skb peer sid``. This will be used by SCTP + TCP style sockets and peeled off connections as they cause a new socket + to be generated. + + If IP security options are configured (CIPSO/CALIPSO), then the ip + options are set on the socket. + + +security_sctp_bind_connect() +----------------------------- +Checks permissions required for ipv4/ipv6 addresses based on the ``@optname`` +as follows:: + + ------------------------------------------------------------------ + | BIND Permission Checks | + | @optname | @address contains | + |----------------------------|-----------------------------------| + | SCTP_SOCKOPT_BINDX_ADD | One or more ipv4 / ipv6 addresses | + | SCTP_PRIMARY_ADDR | Single ipv4 or ipv6 address | + | SCTP_SET_PEER_PRIMARY_ADDR | Single ipv4 or ipv6 address | + ------------------------------------------------------------------ + + ------------------------------------------------------------------ + | CONNECT Permission Checks | + | @optname | @address contains | + |----------------------------|-----------------------------------| + | SCTP_SOCKOPT_CONNECTX | One or more ipv4 / ipv6 addresses | + | SCTP_PARAM_ADD_IP | One or more ipv4 / ipv6 addresses | + | SCTP_SENDMSG_CONNECT | Single ipv4 or ipv6 address | + | SCTP_PARAM_SET_PRIMARY | Single ipv4 or ipv6 address | + ------------------------------------------------------------------ + + +``Documentation/security/LSM-sctp.rst`` gives a summary of the ``@optname`` +entries and also describes ASCONF chunk processing when Dynamic Address +Reconfiguration is enabled. + + +security_sctp_sk_clone() +------------------------- +Called whenever a new socket is created by **accept**\(2) (i.e. a TCP style +socket) or when a socket is 'peeled off' e.g userspace calls +**sctp_peeloff**\(3). ``security_sctp_sk_clone()`` will set the new +sockets sid and peer sid to that contained in the ``@ep sid`` and +``@ep peer sid`` respectively. +:: + + @ep - pointer to current sctp endpoint structure. + @sk - pointer to current sock structure. + @sk - pointer to new sock structure. + + +security_inet_conn_established() +--------------------------------- +Called when a COOKIE ACK is received where it sets the connection's peer sid +to that in ``@skb``:: + + @sk - pointer to sock structure. + @skb - pointer to skbuff of the COOKIE ACK packet. + + +Policy Statements +================== +The following class and permissions to support SCTP are available within the +kernel:: + + class sctp_socket inherits socket { node_bind } + +whenever the following policy capability is enabled:: + + policycap extended_socket_class; + +SELinux SCTP support adds the ``name_connect`` permission for connecting +to a specific port type and the ``association`` permission that is explained +in the section below. + +If userspace tools have been updated, SCTP will support the ``portcon`` +statement as shown in the following example:: + + portcon sctp 1024-1036 system_u:object_r:sctp_ports_t:s0 + + +SCTP Peer Labeling +=================== +An SCTP socket will only have one peer label assigned to it. This will be +assigned during the establishment of the first association. Any further +associations on this socket will have their packet peer label compared to +the sockets peer label, and only if they are different will the +``association`` permission be validated. This is validated by checking the +socket peer sid against the received packets peer sid to determine whether +the association should be allowed or denied. + +NOTES: + 1) If peer labeling is not enabled, then the peer context will always be + ``SECINITSID_UNLABELED`` (``unlabeled_t`` in Reference Policy). + + 2) As SCTP can support more than one transport address per endpoint + (multi-homing) on a single socket, it is possible to configure policy + and NetLabel to provide different peer labels for each of these. As the + socket peer label is determined by the first associations transport + address, it is recommended that all peer labels are consistent. + + 3) **getpeercon**\(3) may be used by userspace to retrieve the sockets peer + context. + + 4) While not SCTP specific, be aware when using NetLabel that if a label + is assigned to a specific interface, and that interface 'goes down', + then the NetLabel service will remove the entry. Therefore ensure that + the network startup scripts call **netlabelctl**\(8) to set the required + label (see **netlabel-config**\(8) helper script for details). + + 5) The NetLabel SCTP peer labeling rules apply as discussed in the following + set of posts tagged "netlabel" at: http://www.paul-moore.com/blog/t. + + 6) CIPSO is only supported for IPv4 addressing: ``socket(AF_INET, ...)`` + CALIPSO is only supported for IPv6 addressing: ``socket(AF_INET6, ...)`` + + Note the following when testing CIPSO/CALIPSO: + a) CIPSO will send an ICMP packet if an SCTP packet cannot be + delivered because of an invalid label. + b) CALIPSO does not send an ICMP packet, just silently discards it. + + 7) IPSEC is not supported as RFC 3554 - sctp/ipsec support has not been + implemented in userspace (**racoon**\(8) or **ipsec_pluto**\(8)), + although the kernel supports SCTP/IPSEC. diff --git a/Documentation/security/index.rst b/Documentation/security/index.rst index 298a94a33f05..85492bfca530 100644 --- a/Documentation/security/index.rst +++ b/Documentation/security/index.rst @@ -9,5 +9,7 @@ Security Documentation IMA-templates keys/index LSM + LSM-sctp + SELinux-sctp self-protection tpm/index diff --git a/Documentation/sound/alsa-configuration.rst b/Documentation/sound/alsa-configuration.rst index aed6b4fb8e46..4d83c1c0ca04 100644 --- a/Documentation/sound/alsa-configuration.rst +++ b/Documentation/sound/alsa-configuration.rst @@ -1062,7 +1062,7 @@ output (with ``--no-upload`` option) to kernel bugzilla or alsa-devel ML (see the section `Links and Addresses`_). ``power_save`` and ``power_save_controller`` options are for power-saving -mode. See powersave.txt for details. +mode. See powersave.rst for details. Note 2: If you get click noises on output, try the module option ``position_fix=1`` or ``2``. ``position_fix=1`` will use the SD_LPIB @@ -1133,7 +1133,7 @@ line_outs_monitor enable_monitor Enable Analog Out on Channel 63/64 by default. -See hdspm.txt for details. +See hdspm.rst for details. Module snd-ice1712 ------------------ @@ -2224,6 +2224,13 @@ quirk_alias Quirk alias list, pass strings like ``0123abcd:5678beef``, which applies the existing quirk for the device 5678:beef to a new device 0123:abcd. +use_vmalloc + Use vmalloc() for allocations of the PCM buffers (default: yes). + For architectures with non-coherent memory like ARM or MIPS, the + mmap access may give inconsistent results with vmalloc'ed + buffers. If mmap is used on such architectures, turn off this + option, so that the DMA-coherent buffers are allocated and used + instead. This module supports multiple devices, autoprobe and hotplugging. diff --git a/Documentation/sound/hd-audio/models.rst b/Documentation/sound/hd-audio/models.rst index 1fee5a4f6660..7c2d37571af0 100644 --- a/Documentation/sound/hd-audio/models.rst +++ b/Documentation/sound/hd-audio/models.rst @@ -263,6 +263,8 @@ hp-dock HP dock support mute-led-gpio Mute LED control via GPIO +hp-mic-fix + Fix for headset mic pin on HP boxes STAC9200 ======== diff --git a/Documentation/sound/soc/codec.rst b/Documentation/sound/soc/codec.rst index f87612b94812..8a9737eb7597 100644 --- a/Documentation/sound/soc/codec.rst +++ b/Documentation/sound/soc/codec.rst @@ -139,7 +139,7 @@ DAPM description ---------------- The Dynamic Audio Power Management description describes the codec power components and their relationships and registers to the ASoC core. -Please read dapm.txt for details of building the description. +Please read dapm.rst for details of building the description. Please also see the examples in other codec drivers. @@ -179,12 +179,12 @@ i.e. static int wm8974_mute(struct snd_soc_dai *dai, int mute) { - struct snd_soc_codec *codec = dai->codec; - u16 mute_reg = snd_soc_read(codec, WM8974_DAC) & 0xffbf; + struct snd_soc_component *component = dai->component; + u16 mute_reg = snd_soc_component_read32(component, WM8974_DAC) & 0xffbf; if (mute) - snd_soc_write(codec, WM8974_DAC, mute_reg | 0x40); + snd_soc_component_write(component, WM8974_DAC, mute_reg | 0x40); else - snd_soc_write(codec, WM8974_DAC, mute_reg); + snd_soc_component_write(component, WM8974_DAC, mute_reg); return 0; } diff --git a/Documentation/sound/soc/platform.rst b/Documentation/sound/soc/platform.rst index d5574904d981..c1badea53d3d 100644 --- a/Documentation/sound/soc/platform.rst +++ b/Documentation/sound/soc/platform.rst @@ -23,30 +23,26 @@ The platform DMA driver optionally supports the following ALSA operations:- }; The platform driver exports its DMA functionality via struct -snd_soc_platform_driver:- +snd_soc_component_driver:- :: - struct snd_soc_platform_driver { - char *name; + struct snd_soc_component_driver { + const char *name; - int (*probe)(struct platform_device *pdev); - int (*remove)(struct platform_device *pdev); - int (*suspend)(struct platform_device *pdev, struct snd_soc_cpu_dai *cpu_dai); - int (*resume)(struct platform_device *pdev, struct snd_soc_cpu_dai *cpu_dai); + ... + int (*probe)(struct snd_soc_component *); + void (*remove)(struct snd_soc_component *); + int (*suspend)(struct snd_soc_component *); + int (*resume)(struct snd_soc_component *); /* pcm creation and destruction */ - int (*pcm_new)(struct snd_card *, struct snd_soc_codec_dai *, struct snd_pcm *); + int (*pcm_new)(struct snd_soc_pcm_runtime *); void (*pcm_free)(struct snd_pcm *); - /* - * For platform caused delay reporting. - * Optional. - */ - snd_pcm_sframes_t (*delay)(struct snd_pcm_substream *, - struct snd_soc_dai *); - - /* platform stream ops */ - struct snd_pcm_ops *pcm_ops; + ... + const struct snd_pcm_ops *ops; + const struct snd_compr_ops *compr_ops; + ... }; Please refer to the ALSA driver documentation for details of audio DMA. @@ -66,7 +62,7 @@ Each SoC DAI driver must provide the following features:- 4. SYSCLK configuration 5. Suspend and resume (optional) -Please see codec.txt for a description of items 1 - 4. +Please see codec.rst for a description of items 1 - 4. SoC DSP Drivers diff --git a/Documentation/sphinx/parse-headers.pl b/Documentation/sphinx/parse-headers.pl index a958d8b5e99d..d410f47567e9 100755 --- a/Documentation/sphinx/parse-headers.pl +++ b/Documentation/sphinx/parse-headers.pl @@ -387,11 +387,11 @@ tree for more details. =head1 BUGS -Report bugs to Mauro Carvalho Chehab <mchehab@s-opensource.com> +Report bugs to Mauro Carvalho Chehab <mchehab@kernel.org> =head1 COPYRIGHT -Copyright (c) 2016 by Mauro Carvalho Chehab <mchehab@s-opensource.com>. +Copyright (c) 2016 by Mauro Carvalho Chehab <mchehab+samsung@kernel.org>. License GPLv2: GNU GPL version 2 <http://gnu.org/licenses/gpl.html>. diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index 412314eebda6..eded671d55eb 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -964,32 +964,34 @@ detect a hard lockup condition. tainted: -Non-zero if the kernel has been tainted. Numeric values, which -can be ORed together: - - 1 - A module with a non-GPL license has been loaded, this - includes modules with no license. - Set by modutils >= 2.4.9 and module-init-tools. - 2 - A module was force loaded by insmod -f. - Set by modutils >= 2.4.9 and module-init-tools. - 4 - Unsafe SMP processors: SMP with CPUs not designed for SMP. - 8 - A module was forcibly unloaded from the system by rmmod -f. - 16 - A hardware machine check error occurred on the system. - 32 - A bad page was discovered on the system. - 64 - The user has asked that the system be marked "tainted". This - could be because they are running software that directly modifies - the hardware, or for other reasons. - 128 - The system has died. - 256 - The ACPI DSDT has been overridden with one supplied by the user - instead of using the one provided by the hardware. - 512 - A kernel warning has occurred. -1024 - A module from drivers/staging was loaded. -2048 - The system is working around a severe firmware bug. -4096 - An out-of-tree module has been loaded. -8192 - An unsigned module has been loaded in a kernel supporting module - signature. -16384 - A soft lockup has previously occurred on the system. -32768 - The kernel has been live patched. +Non-zero if the kernel has been tainted. Numeric values, which can be +ORed together. The letters are seen in "Tainted" line of Oops reports. + + 1 (P): A module with a non-GPL license has been loaded, this + includes modules with no license. + Set by modutils >= 2.4.9 and module-init-tools. + 2 (F): A module was force loaded by insmod -f. + Set by modutils >= 2.4.9 and module-init-tools. + 4 (S): Unsafe SMP processors: SMP with CPUs not designed for SMP. + 8 (R): A module was forcibly unloaded from the system by rmmod -f. + 16 (M): A hardware machine check error occurred on the system. + 32 (B): A bad page was discovered on the system. + 64 (U): The user has asked that the system be marked "tainted". This + could be because they are running software that directly modifies + the hardware, or for other reasons. + 128 (D): The system has died. + 256 (A): The ACPI DSDT has been overridden with one supplied by the user + instead of using the one provided by the hardware. + 512 (W): A kernel warning has occurred. + 1024 (C): A module from drivers/staging was loaded. + 2048 (I): The system is working around a severe firmware bug. + 4096 (O): An out-of-tree module has been loaded. + 8192 (E): An unsigned module has been loaded in a kernel supporting module + signature. + 16384 (L): A soft lockup has previously occurred on the system. + 32768 (K): The kernel has been live patched. + 65536 (X): Auxiliary taint, defined and used by for distros. +131072 (T): The kernel was built with the struct randomization plugin. ============================================================== diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index ff234d229cbb..697ef8c225df 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -312,8 +312,6 @@ The lowmem_reserve_ratio is an array. You can see them by reading this file. % cat /proc/sys/vm/lowmem_reserve_ratio 256 256 32 - -Note: # of this elements is one fewer than number of zones. Because the highest - zone's value is not necessary for following calculation. But, these values are not used directly. The kernel calculates # of protection pages for each zones from them. These are shown as array of protection pages @@ -364,7 +362,8 @@ As above expression, they are reciprocal number of ratio. pages of higher zones on the node. If you would like to protect more pages, smaller values are effective. -The minimum value is 1 (1/1 -> 100%). +The minimum value is 1 (1/1 -> 100%). The value less than 1 completely +disables protection of the pages. ============================================================== @@ -516,7 +515,7 @@ nr_hugepages Change the minimum size of the hugepage pool. -See Documentation/vm/hugetlbpage.txt +See Documentation/admin-guide/mm/hugetlbpage.rst ============================================================== @@ -525,7 +524,7 @@ nr_overcommit_hugepages Change the maximum size of the hugepage pool. The maximum is nr_hugepages + nr_overcommit_hugepages. -See Documentation/vm/hugetlbpage.txt +See Documentation/admin-guide/mm/hugetlbpage.rst ============================================================== @@ -668,7 +667,7 @@ and don't use much of it. The default value is 0. -See Documentation/vm/overcommit-accounting and +See Documentation/vm/overcommit-accounting.rst and mm/mmap.c::__vm_enough_memory() for more information. ============================================================== diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt index bb9a0a53e76b..911399730c1c 100644 --- a/Documentation/thermal/sysfs-api.txt +++ b/Documentation/thermal/sysfs-api.txt @@ -255,6 +255,7 @@ temperature) and throttle appropriate devices. 2. sysfs attributes structure RO read only value +WO write only value RW read/write value Thermal sysfs attributes will be represented under /sys/class/thermal. @@ -286,6 +287,11 @@ Thermal cooling device sys I/F, created once it's registered: |---type: Type of the cooling device(processor/fan/...) |---max_state: Maximum cooling state of the cooling device |---cur_state: Current cooling state of the cooling device + |---stats: Directory containing cooling device's statistics + |---stats/reset: Writing any value resets the statistics + |---stats/time_in_state_ms: Time (msec) spent in various cooling states + |---stats/total_trans: Total number of times cooling state is changed + |---stats/trans_table: Cooing state transition table Then next two dynamic attributes are created/removed in pairs. They represent @@ -490,6 +496,31 @@ cur_state - cur_state == max_state means the maximum cooling. RW, Required +stats/reset + Writing any value resets the cooling device's statistics. + WO, Required + +stats/time_in_state_ms: + The amount of time spent by the cooling device in various cooling + states. The output will have "<state> <time>" pair in each line, which + will mean this cooling device spent <time> msec of time at <state>. + Output will have one line for each of the supported states. usertime + units here is 10mS (similar to other time exported in /proc). + RO, Required + +stats/total_trans: + A single positive value showing the total number of times the state of a + cooling device is changed. + RO, Required + +stats/trans_table: + This gives fine grained information about all the cooling state + transitions. The cat output here is a two dimensional matrix, where an + entry <i,j> (row i, column j) represents the number of transitions from + State_i to State_j. If the transition table is bigger than PAGE_SIZE, + reading this will return an -EFBIG error. + RO, Required + 3. A simple implementation ACPI thermal zone may support multiple trip points like critical, hot, diff --git a/Documentation/trace/coresight-cpu-debug.txt b/Documentation/trace/coresight-cpu-debug.txt index 2b9b51cd501e..89ab09e78e8d 100644 --- a/Documentation/trace/coresight-cpu-debug.txt +++ b/Documentation/trace/coresight-cpu-debug.txt @@ -177,11 +177,11 @@ Here is an example of the debugging output format: ARM external debug module: coresight-cpu-debug 850000.debug: CPU[0]: coresight-cpu-debug 850000.debug: EDPRSR: 00000001 (Power:On DLK:Unlock) -coresight-cpu-debug 850000.debug: EDPCSR: [<ffff00000808e9bc>] handle_IPI+0x174/0x1d8 +coresight-cpu-debug 850000.debug: EDPCSR: handle_IPI+0x174/0x1d8 coresight-cpu-debug 850000.debug: EDCIDSR: 00000000 coresight-cpu-debug 850000.debug: EDVIDSR: 90000000 (State:Non-secure Mode:EL1/0 Width:64bits VMID:0) coresight-cpu-debug 852000.debug: CPU[1]: coresight-cpu-debug 852000.debug: EDPRSR: 00000001 (Power:On DLK:Unlock) -coresight-cpu-debug 852000.debug: EDPCSR: [<ffff0000087fab34>] debug_notifier_call+0x23c/0x358 +coresight-cpu-debug 852000.debug: EDPCSR: debug_notifier_call+0x23c/0x358 coresight-cpu-debug 852000.debug: EDCIDSR: 00000000 coresight-cpu-debug 852000.debug: EDVIDSR: 90000000 (State:Non-secure Mode:EL1/0 Width:64bits VMID:0) diff --git a/Documentation/trace/coresight.txt b/Documentation/trace/coresight.txt index 6f0120c3a4f1..1d74ad0202b6 100644 --- a/Documentation/trace/coresight.txt +++ b/Documentation/trace/coresight.txt @@ -187,13 +187,19 @@ that can be performed on them (see "struct coresight_ops"). The specific to that component only. "Implementation defined" customisations are expected to be accessed and controlled using those entries. -Last but not least, "struct module *owner" is expected to be set to reflect -the information carried in "THIS_MODULE". How to use the tracer modules ----------------------------- -Before trace collection can start, a coresight sink needs to be identify. +There are two ways to use the Coresight framework: 1) using the perf cmd line +tools and 2) interacting directly with the Coresight devices using the sysFS +interface. Preference is given to the former as using the sysFS interface +requires a deep understanding of the Coresight HW. The following sections +provide details on using both methods. + +1) Using the sysFS interface: + +Before trace collection can start, a coresight sink needs to be identified. There is no limit on the amount of sinks (nor sources) that can be enabled at any given moment. As a generic operation, all device pertaining to the sink class will have an "active" entry in sysfs: @@ -298,42 +304,48 @@ Instruction 13570831 0x8026B584 E28DD00C false ADD Instruction 0 0x8026B588 E8BD8000 true LDM sp!,{pc} Timestamp Timestamp: 17107041535 -How to use the STM module -------------------------- +2) Using perf framework: -Using the System Trace Macrocell module is the same as the tracers - the only -difference is that clients are driving the trace capture rather -than the program flow through the code. +Coresight tracers are represented using the Perf framework's Performance +Monitoring Unit (PMU) abstraction. As such the perf framework takes charge of +controlling when tracing gets enabled based on when the process of interest is +scheduled. When configured in a system, Coresight PMUs will be listed when +queried by the perf command line tool: -As with any other CoreSight component, specifics about the STM tracer can be -found in sysfs with more information on each entry being found in [1]: + linaro@linaro-nano:~$ ./perf list pmu -root@genericarmv8:~# ls /sys/bus/coresight/devices/20100000.stm -enable_source hwevent_select port_enable subsystem uevent -hwevent_enable mgmt port_select traceid -root@genericarmv8:~# + List of pre-defined events (to be used in -e): -Like any other source a sink needs to be identified and the STM enabled before -being used: + cs_etm// [Kernel PMU event] -root@genericarmv8:~# echo 1 > /sys/bus/coresight/devices/20010000.etf/enable_sink -root@genericarmv8:~# echo 1 > /sys/bus/coresight/devices/20100000.stm/enable_source + linaro@linaro-nano:~$ -From there user space applications can request and use channels using the devfs -interface provided for that purpose by the generic STM API: +Regardless of the number of tracers available in a system (usually equal to the +amount of processor cores), the "cs_etm" PMU will be listed only once. -root@genericarmv8:~# ls -l /dev/20100000.stm -crw------- 1 root root 10, 61 Jan 3 18:11 /dev/20100000.stm -root@genericarmv8:~# +A Coresight PMU works the same way as any other PMU, i.e the name of the PMU is +listed along with configuration options within forward slashes '/'. Since a +Coresight system will typically have more than one sink, the name of the sink to +work with needs to be specified as an event option. Names for sink to choose +from are listed in sysFS under ($SYSFS)/bus/coresight/devices: -Details on how to use the generic STM API can be found here [2]. + root@linaro-nano:~# ls /sys/bus/coresight/devices/ + 20010000.etf 20040000.funnel 20100000.stm 22040000.etm + 22140000.etm 230c0000.funnel 23240000.etm 20030000.tpiu + 20070000.etr 20120000.replicator 220c0000.funnel + 23040000.etm 23140000.etm 23340000.etm -[1]. Documentation/ABI/testing/sysfs-bus-coresight-devices-stm -[2]. Documentation/trace/stm.txt + root@linaro-nano:~# perf record -e cs_etm/@20070000.etr/u --per-thread program +The syntax within the forward slashes '/' is important. The '@' character +tells the parser that a sink is about to be specified and that this is the sink +to use for the trace session. -Using perf tools ----------------- +More information on the above and other example on how to use Coresight with +the perf tools can be found in the "HOWTO.md" file of the openCSD gitHub +repository [3]. + +2.1) AutoFDO analysis using the perf tools: perf can be used to record and analyze trace of programs. @@ -381,3 +393,38 @@ sort example is from the AutoFDO tutorial (https://gcc.gnu.org/wiki/AutoFDO/Tuto $ taskset -c 2 ./sort_autofdo Bubble sorting array of 30000 elements 5806 ms + + +How to use the STM module +------------------------- + +Using the System Trace Macrocell module is the same as the tracers - the only +difference is that clients are driving the trace capture rather +than the program flow through the code. + +As with any other CoreSight component, specifics about the STM tracer can be +found in sysfs with more information on each entry being found in [1]: + +root@genericarmv8:~# ls /sys/bus/coresight/devices/20100000.stm +enable_source hwevent_select port_enable subsystem uevent +hwevent_enable mgmt port_select traceid +root@genericarmv8:~# + +Like any other source a sink needs to be identified and the STM enabled before +being used: + +root@genericarmv8:~# echo 1 > /sys/bus/coresight/devices/20010000.etf/enable_sink +root@genericarmv8:~# echo 1 > /sys/bus/coresight/devices/20100000.stm/enable_source + +From there user space applications can request and use channels using the devfs +interface provided for that purpose by the generic STM API: + +root@genericarmv8:~# ls -l /dev/20100000.stm +crw------- 1 root root 10, 61 Jan 3 18:11 /dev/20100000.stm +root@genericarmv8:~# + +Details on how to use the generic STM API can be found here [2]. + +[1]. Documentation/ABI/testing/sysfs-bus-coresight-devices-stm +[2]. Documentation/trace/stm.txt +[3]. https://github.com/Linaro/perf-opencsd diff --git a/Documentation/trace/events.rst b/Documentation/trace/events.rst index bdf1963ba6ba..a5ea2cb0082b 100644 --- a/Documentation/trace/events.rst +++ b/Documentation/trace/events.rst @@ -520,1550 +520,4 @@ The following commands are supported: totals derived from one or more trace event format fields and/or event counts (hitcount). - The format of a hist trigger is as follows:: - - hist:keys=<field1[,field2,...]>[:values=<field1[,field2,...]>] - [:sort=<field1[,field2,...]>][:size=#entries][:pause][:continue] - [:clear][:name=histname1] [if <filter>] - - When a matching event is hit, an entry is added to a hash table - using the key(s) and value(s) named. Keys and values correspond to - fields in the event's format description. Values must correspond to - numeric fields - on an event hit, the value(s) will be added to a - sum kept for that field. The special string 'hitcount' can be used - in place of an explicit value field - this is simply a count of - event hits. If 'values' isn't specified, an implicit 'hitcount' - value will be automatically created and used as the only value. - Keys can be any field, or the special string 'stacktrace', which - will use the event's kernel stacktrace as the key. The keywords - 'keys' or 'key' can be used to specify keys, and the keywords - 'values', 'vals', or 'val' can be used to specify values. Compound - keys consisting of up to two fields can be specified by the 'keys' - keyword. Hashing a compound key produces a unique entry in the - table for each unique combination of component keys, and can be - useful for providing more fine-grained summaries of event data. - Additionally, sort keys consisting of up to two fields can be - specified by the 'sort' keyword. If more than one field is - specified, the result will be a 'sort within a sort': the first key - is taken to be the primary sort key and the second the secondary - key. If a hist trigger is given a name using the 'name' parameter, - its histogram data will be shared with other triggers of the same - name, and trigger hits will update this common data. Only triggers - with 'compatible' fields can be combined in this way; triggers are - 'compatible' if the fields named in the trigger share the same - number and type of fields and those fields also have the same names. - Note that any two events always share the compatible 'hitcount' and - 'stacktrace' fields and can therefore be combined using those - fields, however pointless that may be. - - 'hist' triggers add a 'hist' file to each event's subdirectory. - Reading the 'hist' file for the event will dump the hash table in - its entirety to stdout. If there are multiple hist triggers - attached to an event, there will be a table for each trigger in the - output. The table displayed for a named trigger will be the same as - any other instance having the same name. Each printed hash table - entry is a simple list of the keys and values comprising the entry; - keys are printed first and are delineated by curly braces, and are - followed by the set of value fields for the entry. By default, - numeric fields are displayed as base-10 integers. This can be - modified by appending any of the following modifiers to the field - name: - - - .hex display a number as a hex value - - .sym display an address as a symbol - - .sym-offset display an address as a symbol and offset - - .syscall display a syscall id as a system call name - - .execname display a common_pid as a program name - - Note that in general the semantics of a given field aren't - interpreted when applying a modifier to it, but there are some - restrictions to be aware of in this regard: - - - only the 'hex' modifier can be used for values (because values - are essentially sums, and the other modifiers don't make sense - in that context). - - the 'execname' modifier can only be used on a 'common_pid'. The - reason for this is that the execname is simply the 'comm' value - saved for the 'current' process when an event was triggered, - which is the same as the common_pid value saved by the event - tracing code. Trying to apply that comm value to other pid - values wouldn't be correct, and typically events that care save - pid-specific comm fields in the event itself. - - A typical usage scenario would be the following to enable a hist - trigger, read its current contents, and then turn it off:: - - # echo 'hist:keys=skbaddr.hex:vals=len' > \ - /sys/kernel/debug/tracing/events/net/netif_rx/trigger - - # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist - - # echo '!hist:keys=skbaddr.hex:vals=len' > \ - /sys/kernel/debug/tracing/events/net/netif_rx/trigger - - The trigger file itself can be read to show the details of the - currently attached hist trigger. This information is also displayed - at the top of the 'hist' file when read. - - By default, the size of the hash table is 2048 entries. The 'size' - parameter can be used to specify more or fewer than that. The units - are in terms of hashtable entries - if a run uses more entries than - specified, the results will show the number of 'drops', the number - of hits that were ignored. The size should be a power of 2 between - 128 and 131072 (any non- power-of-2 number specified will be rounded - up). - - The 'sort' parameter can be used to specify a value field to sort - on. The default if unspecified is 'hitcount' and the default sort - order is 'ascending'. To sort in the opposite direction, append - .descending' to the sort key. - - The 'pause' parameter can be used to pause an existing hist trigger - or to start a hist trigger but not log any events until told to do - so. 'continue' or 'cont' can be used to start or restart a paused - hist trigger. - - The 'clear' parameter will clear the contents of a running hist - trigger and leave its current paused/active state. - - Note that the 'pause', 'cont', and 'clear' parameters should be - applied using 'append' shell operator ('>>') if applied to an - existing trigger, rather than via the '>' operator, which will cause - the trigger to be removed through truncation. - -- enable_hist/disable_hist - - The enable_hist and disable_hist triggers can be used to have one - event conditionally start and stop another event's already-attached - hist trigger. Any number of enable_hist and disable_hist triggers - can be attached to a given event, allowing that event to kick off - and stop aggregations on a host of other events. - - The format is very similar to the enable/disable_event triggers:: - - enable_hist:<system>:<event>[:count] - disable_hist:<system>:<event>[:count] - - Instead of enabling or disabling the tracing of the target event - into the trace buffer as the enable/disable_event triggers do, the - enable/disable_hist triggers enable or disable the aggregation of - the target event into a hash table. - - A typical usage scenario for the enable_hist/disable_hist triggers - would be to first set up a paused hist trigger on some event, - followed by an enable_hist/disable_hist pair that turns the hist - aggregation on and off when conditions of interest are hit:: - - # echo 'hist:keys=skbaddr.hex:vals=len:pause' > \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - - # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger - - # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger - - The above sets up an initially paused hist trigger which is unpaused - and starts aggregating events when a given program is executed, and - which stops aggregating when the process exits and the hist trigger - is paused again. - - The examples below provide a more concrete illustration of the - concepts and typical usage patterns discussed above. - - -6.2 'hist' trigger examples ---------------------------- - - The first set of examples creates aggregations using the kmalloc - event. The fields that can be used for the hist trigger are listed - in the kmalloc event's format file:: - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/format - name: kmalloc - ID: 374 - format: - field:unsigned short common_type; offset:0; size:2; signed:0; - field:unsigned char common_flags; offset:2; size:1; signed:0; - field:unsigned char common_preempt_count; offset:3; size:1; signed:0; - field:int common_pid; offset:4; size:4; signed:1; - - field:unsigned long call_site; offset:8; size:8; signed:0; - field:const void * ptr; offset:16; size:8; signed:0; - field:size_t bytes_req; offset:24; size:8; signed:0; - field:size_t bytes_alloc; offset:32; size:8; signed:0; - field:gfp_t gfp_flags; offset:40; size:4; signed:0; - - We'll start by creating a hist trigger that generates a simple table - that lists the total number of bytes requested for each function in - the kernel that made one or more calls to kmalloc:: - - # echo 'hist:key=call_site:val=bytes_req' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - This tells the tracing system to create a 'hist' trigger using the - call_site field of the kmalloc event as the key for the table, which - just means that each unique call_site address will have an entry - created for it in the table. The 'val=bytes_req' parameter tells - the hist trigger that for each unique entry (call_site) in the - table, it should keep a running total of the number of bytes - requested by that call_site. - - We'll let it run for awhile and then dump the contents of the 'hist' - file in the kmalloc event's subdirectory (for readability, a number - of entries have been omitted):: - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active] - - { call_site: 18446744072106379007 } hitcount: 1 bytes_req: 176 - { call_site: 18446744071579557049 } hitcount: 1 bytes_req: 1024 - { call_site: 18446744071580608289 } hitcount: 1 bytes_req: 16384 - { call_site: 18446744071581827654 } hitcount: 1 bytes_req: 24 - { call_site: 18446744071580700980 } hitcount: 1 bytes_req: 8 - { call_site: 18446744071579359876 } hitcount: 1 bytes_req: 152 - { call_site: 18446744071580795365 } hitcount: 3 bytes_req: 144 - { call_site: 18446744071581303129 } hitcount: 3 bytes_req: 144 - { call_site: 18446744071580713234 } hitcount: 4 bytes_req: 2560 - { call_site: 18446744071580933750 } hitcount: 4 bytes_req: 736 - . - . - . - { call_site: 18446744072106047046 } hitcount: 69 bytes_req: 5576 - { call_site: 18446744071582116407 } hitcount: 73 bytes_req: 2336 - { call_site: 18446744072106054684 } hitcount: 136 bytes_req: 140504 - { call_site: 18446744072106224230 } hitcount: 136 bytes_req: 19584 - { call_site: 18446744072106078074 } hitcount: 153 bytes_req: 2448 - { call_site: 18446744072106062406 } hitcount: 153 bytes_req: 36720 - { call_site: 18446744071582507929 } hitcount: 153 bytes_req: 37088 - { call_site: 18446744072102520590 } hitcount: 273 bytes_req: 10920 - { call_site: 18446744071582143559 } hitcount: 358 bytes_req: 716 - { call_site: 18446744072106465852 } hitcount: 417 bytes_req: 56712 - { call_site: 18446744072102523378 } hitcount: 485 bytes_req: 27160 - { call_site: 18446744072099568646 } hitcount: 1676 bytes_req: 33520 - - Totals: - Hits: 4610 - Entries: 45 - Dropped: 0 - - The output displays a line for each entry, beginning with the key - specified in the trigger, followed by the value(s) also specified in - the trigger. At the beginning of the output is a line that displays - the trigger info, which can also be displayed by reading the - 'trigger' file:: - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active] - - At the end of the output are a few lines that display the overall - totals for the run. The 'Hits' field shows the total number of - times the event trigger was hit, the 'Entries' field shows the total - number of used entries in the hash table, and the 'Dropped' field - shows the number of hits that were dropped because the number of - used entries for the run exceeded the maximum number of entries - allowed for the table (normally 0, but if not a hint that you may - want to increase the size of the table using the 'size' parameter). - - Notice in the above output that there's an extra field, 'hitcount', - which wasn't specified in the trigger. Also notice that in the - trigger info output, there's a parameter, 'sort=hitcount', which - wasn't specified in the trigger either. The reason for that is that - every trigger implicitly keeps a count of the total number of hits - attributed to a given entry, called the 'hitcount'. That hitcount - information is explicitly displayed in the output, and in the - absence of a user-specified sort parameter, is used as the default - sort field. - - The value 'hitcount' can be used in place of an explicit value in - the 'values' parameter if you don't really need to have any - particular field summed and are mainly interested in hit - frequencies. - - To turn the hist trigger off, simply call up the trigger in the - command history and re-execute it with a '!' prepended:: - - # echo '!hist:key=call_site:val=bytes_req' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - Finally, notice that the call_site as displayed in the output above - isn't really very useful. It's an address, but normally addresses - are displayed in hex. To have a numeric field displayed as a hex - value, simply append '.hex' to the field name in the trigger:: - - # echo 'hist:key=call_site.hex:val=bytes_req' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=call_site.hex:vals=bytes_req:sort=hitcount:size=2048 [active] - - { call_site: ffffffffa026b291 } hitcount: 1 bytes_req: 433 - { call_site: ffffffffa07186ff } hitcount: 1 bytes_req: 176 - { call_site: ffffffff811ae721 } hitcount: 1 bytes_req: 16384 - { call_site: ffffffff811c5134 } hitcount: 1 bytes_req: 8 - { call_site: ffffffffa04a9ebb } hitcount: 1 bytes_req: 511 - { call_site: ffffffff8122e0a6 } hitcount: 1 bytes_req: 12 - { call_site: ffffffff8107da84 } hitcount: 1 bytes_req: 152 - { call_site: ffffffff812d8246 } hitcount: 1 bytes_req: 24 - { call_site: ffffffff811dc1e5 } hitcount: 3 bytes_req: 144 - { call_site: ffffffffa02515e8 } hitcount: 3 bytes_req: 648 - { call_site: ffffffff81258159 } hitcount: 3 bytes_req: 144 - { call_site: ffffffff811c80f4 } hitcount: 4 bytes_req: 544 - . - . - . - { call_site: ffffffffa06c7646 } hitcount: 106 bytes_req: 8024 - { call_site: ffffffffa06cb246 } hitcount: 132 bytes_req: 31680 - { call_site: ffffffffa06cef7a } hitcount: 132 bytes_req: 2112 - { call_site: ffffffff8137e399 } hitcount: 132 bytes_req: 23232 - { call_site: ffffffffa06c941c } hitcount: 185 bytes_req: 171360 - { call_site: ffffffffa06f2a66 } hitcount: 185 bytes_req: 26640 - { call_site: ffffffffa036a70e } hitcount: 265 bytes_req: 10600 - { call_site: ffffffff81325447 } hitcount: 292 bytes_req: 584 - { call_site: ffffffffa072da3c } hitcount: 446 bytes_req: 60656 - { call_site: ffffffffa036b1f2 } hitcount: 526 bytes_req: 29456 - { call_site: ffffffffa0099c06 } hitcount: 1780 bytes_req: 35600 - - Totals: - Hits: 4775 - Entries: 46 - Dropped: 0 - - Even that's only marginally more useful - while hex values do look - more like addresses, what users are typically more interested in - when looking at text addresses are the corresponding symbols - instead. To have an address displayed as symbolic value instead, - simply append '.sym' or '.sym-offset' to the field name in the - trigger:: - - # echo 'hist:key=call_site.sym:val=bytes_req' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=hitcount:size=2048 [active] - - { call_site: [ffffffff810adcb9] syslog_print_all } hitcount: 1 bytes_req: 1024 - { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 - { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 - { call_site: [ffffffff8154acbe] usb_alloc_urb } hitcount: 1 bytes_req: 192 - { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 - { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40 - { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 - { call_site: [ffffffff811febd5] fsnotify_alloc_group } hitcount: 2 bytes_req: 528 - { call_site: [ffffffff81440f58] __tty_buffer_request_room } hitcount: 2 bytes_req: 2624 - { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 2 bytes_req: 96 - { call_site: [ffffffffa05e19af] ieee80211_start_tx_ba_session [mac80211] } hitcount: 2 bytes_req: 464 - { call_site: [ffffffff81672406] tcp_get_metrics } hitcount: 2 bytes_req: 304 - { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 - { call_site: [ffffffff81089b05] sched_create_group } hitcount: 2 bytes_req: 1424 - . - . - . - { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1185 bytes_req: 123240 - { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 1185 bytes_req: 104280 - { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 1402 bytes_req: 190672 - { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 1518 bytes_req: 146208 - { call_site: [ffffffffa029070e] drm_vma_node_allow [drm] } hitcount: 1746 bytes_req: 69840 - { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 2021 bytes_req: 792312 - { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 2592 bytes_req: 145152 - { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2629 bytes_req: 378576 - { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2629 bytes_req: 3783248 - { call_site: [ffffffff81325607] apparmor_file_alloc_security } hitcount: 5192 bytes_req: 10384 - { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 5529 bytes_req: 110584 - { call_site: [ffffffff8131ebf7] aa_alloc_task_context } hitcount: 21943 bytes_req: 702176 - { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 55759 bytes_req: 5074265 - - Totals: - Hits: 109928 - Entries: 71 - Dropped: 0 - - Because the default sort key above is 'hitcount', the above shows a - the list of call_sites by increasing hitcount, so that at the bottom - we see the functions that made the most kmalloc calls during the - run. If instead we we wanted to see the top kmalloc callers in - terms of the number of bytes requested rather than the number of - calls, and we wanted the top caller to appear at the top, we can use - the 'sort' parameter, along with the 'descending' modifier:: - - # echo 'hist:key=call_site.sym:val=bytes_req:sort=bytes_req.descending' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=bytes_req.descending:size=2048 [active] - - { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2186 bytes_req: 3397464 - { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1790 bytes_req: 712176 - { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 8132 bytes_req: 513135 - { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 106 bytes_req: 440128 - { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2186 bytes_req: 314784 - { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 2174 bytes_req: 208992 - { call_site: [ffffffff811ae8e1] __kmalloc } hitcount: 8 bytes_req: 131072 - { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 859 bytes_req: 116824 - { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 1834 bytes_req: 102704 - { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 972 bytes_req: 101088 - { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 972 bytes_req: 85536 - { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 3333 bytes_req: 66664 - { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 209 bytes_req: 61632 - . - . - . - { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 - { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 - { call_site: [ffffffff812d8406] copy_semundo } hitcount: 2 bytes_req: 48 - { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 1 bytes_req: 48 - { call_site: [ffffffffa027121a] drm_getmagic [drm] } hitcount: 1 bytes_req: 48 - { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40 - { call_site: [ffffffff811c52f4] bprm_change_interp } hitcount: 2 bytes_req: 16 - { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 - { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 - { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 - - Totals: - Hits: 32133 - Entries: 81 - Dropped: 0 - - To display the offset and size information in addition to the symbol - name, just use 'sym-offset' instead:: - - # echo 'hist:key=call_site.sym-offset:val=bytes_req:sort=bytes_req.descending' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=call_site.sym-offset:vals=bytes_req:sort=bytes_req.descending:size=2048 [active] - - { call_site: [ffffffffa046041c] i915_gem_execbuffer2+0x6c/0x2c0 [i915] } hitcount: 4569 bytes_req: 3163720 - { call_site: [ffffffffa0489a66] intel_ring_begin+0xc6/0x1f0 [i915] } hitcount: 4569 bytes_req: 657936 - { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23+0x694/0x1020 [i915] } hitcount: 1519 bytes_req: 472936 - { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23+0x516/0x1020 [i915] } hitcount: 3050 bytes_req: 211832 - { call_site: [ffffffff811e2a1b] seq_buf_alloc+0x1b/0x50 } hitcount: 34 bytes_req: 148384 - { call_site: [ffffffffa04a580c] intel_crtc_page_flip+0xbc/0x870 [i915] } hitcount: 1385 bytes_req: 144040 - { call_site: [ffffffff811ae8e1] __kmalloc+0x191/0x1b0 } hitcount: 8 bytes_req: 131072 - { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl+0x282/0x360 [drm] } hitcount: 1385 bytes_req: 121880 - { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc+0x32/0x100 [drm] } hitcount: 1848 bytes_req: 103488 - { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state+0x2c/0xa0 [i915] } hitcount: 461 bytes_req: 62696 - { call_site: [ffffffffa029070e] drm_vma_node_allow+0x2e/0xd0 [drm] } hitcount: 1541 bytes_req: 61640 - { call_site: [ffffffff815f8d7b] sk_prot_alloc+0xcb/0x1b0 } hitcount: 57 bytes_req: 57456 - . - . - . - { call_site: [ffffffff8109524a] alloc_fair_sched_group+0x5a/0x1a0 } hitcount: 2 bytes_req: 128 - { call_site: [ffffffffa027b921] drm_vm_open_locked+0x31/0xa0 [drm] } hitcount: 3 bytes_req: 96 - { call_site: [ffffffff8122e266] proc_self_follow_link+0x76/0xb0 } hitcount: 8 bytes_req: 96 - { call_site: [ffffffff81213e80] load_elf_binary+0x240/0x1650 } hitcount: 3 bytes_req: 84 - { call_site: [ffffffff8154bc62] usb_control_msg+0x42/0x110 } hitcount: 1 bytes_req: 8 - { call_site: [ffffffffa00bf6fe] hidraw_send_report+0x7e/0x1a0 [hid] } hitcount: 1 bytes_req: 7 - { call_site: [ffffffffa00bf1ca] hidraw_report_event+0x8a/0x120 [hid] } hitcount: 1 bytes_req: 7 - - Totals: - Hits: 26098 - Entries: 64 - Dropped: 0 - - We can also add multiple fields to the 'values' parameter. For - example, we might want to see the total number of bytes allocated - alongside bytes requested, and display the result sorted by bytes - allocated in a descending order:: - - # echo 'hist:keys=call_site.sym:values=bytes_req,bytes_alloc:sort=bytes_alloc.descending' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=call_site.sym:vals=bytes_req,bytes_alloc:sort=bytes_alloc.descending:size=2048 [active] - - { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 7403 bytes_req: 4084360 bytes_alloc: 5958016 - { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 541 bytes_req: 2213968 bytes_alloc: 2228224 - { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 7404 bytes_req: 1066176 bytes_alloc: 1421568 - { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1565 bytes_req: 557368 bytes_alloc: 1037760 - { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 9557 bytes_req: 595778 bytes_alloc: 695744 - { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 5839 bytes_req: 430680 bytes_alloc: 470400 - { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 2388 bytes_req: 324768 bytes_alloc: 458496 - { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 3911 bytes_req: 219016 bytes_alloc: 250304 - { call_site: [ffffffff815f8d7b] sk_prot_alloc } hitcount: 235 bytes_req: 236880 bytes_alloc: 240640 - { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 557 bytes_req: 169024 bytes_alloc: 221760 - { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 9378 bytes_req: 187548 bytes_alloc: 206312 - { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1519 bytes_req: 157976 bytes_alloc: 194432 - . - . - . - { call_site: [ffffffff8109bd3b] sched_autogroup_create_attach } hitcount: 2 bytes_req: 144 bytes_alloc: 192 - { call_site: [ffffffff81097ee8] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 - { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 - { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 - { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 - { call_site: [ffffffff81213e80] load_elf_binary } hitcount: 3 bytes_req: 84 bytes_alloc: 96 - { call_site: [ffffffff81079a2e] kthread_create_on_node } hitcount: 1 bytes_req: 56 bytes_alloc: 64 - { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8 - { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 bytes_alloc: 8 - { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8 - - Totals: - Hits: 66598 - Entries: 65 - Dropped: 0 - - Finally, to finish off our kmalloc example, instead of simply having - the hist trigger display symbolic call_sites, we can have the hist - trigger additionally display the complete set of kernel stack traces - that led to each call_site. To do that, we simply use the special - value 'stacktrace' for the key parameter:: - - # echo 'hist:keys=stacktrace:values=bytes_req,bytes_alloc:sort=bytes_alloc' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - The above trigger will use the kernel stack trace in effect when an - event is triggered as the key for the hash table. This allows the - enumeration of every kernel callpath that led up to a particular - event, along with a running total of any of the event fields for - that event. Here we tally bytes requested and bytes allocated for - every callpath in the system that led up to a kmalloc (in this case - every callpath to a kmalloc for a kernel compile):: - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=stacktrace:vals=bytes_req,bytes_alloc:sort=bytes_alloc:size=2048 [active] - - { stacktrace: - __kmalloc_track_caller+0x10b/0x1a0 - kmemdup+0x20/0x50 - hidraw_report_event+0x8a/0x120 [hid] - hid_report_raw_event+0x3ea/0x440 [hid] - hid_input_report+0x112/0x190 [hid] - hid_irq_in+0xc2/0x260 [usbhid] - __usb_hcd_giveback_urb+0x72/0x120 - usb_giveback_urb_bh+0x9e/0xe0 - tasklet_hi_action+0xf8/0x100 - __do_softirq+0x114/0x2c0 - irq_exit+0xa5/0xb0 - do_IRQ+0x5a/0xf0 - ret_from_intr+0x0/0x30 - cpuidle_enter+0x17/0x20 - cpu_startup_entry+0x315/0x3e0 - rest_init+0x7c/0x80 - } hitcount: 3 bytes_req: 21 bytes_alloc: 24 - { stacktrace: - __kmalloc_track_caller+0x10b/0x1a0 - kmemdup+0x20/0x50 - hidraw_report_event+0x8a/0x120 [hid] - hid_report_raw_event+0x3ea/0x440 [hid] - hid_input_report+0x112/0x190 [hid] - hid_irq_in+0xc2/0x260 [usbhid] - __usb_hcd_giveback_urb+0x72/0x120 - usb_giveback_urb_bh+0x9e/0xe0 - tasklet_hi_action+0xf8/0x100 - __do_softirq+0x114/0x2c0 - irq_exit+0xa5/0xb0 - do_IRQ+0x5a/0xf0 - ret_from_intr+0x0/0x30 - } hitcount: 3 bytes_req: 21 bytes_alloc: 24 - { stacktrace: - kmem_cache_alloc_trace+0xeb/0x150 - aa_alloc_task_context+0x27/0x40 - apparmor_cred_prepare+0x1f/0x50 - security_prepare_creds+0x16/0x20 - prepare_creds+0xdf/0x1a0 - SyS_capset+0xb5/0x200 - system_call_fastpath+0x12/0x6a - } hitcount: 1 bytes_req: 32 bytes_alloc: 32 - . - . - . - { stacktrace: - __kmalloc+0x11b/0x1b0 - i915_gem_execbuffer2+0x6c/0x2c0 [i915] - drm_ioctl+0x349/0x670 [drm] - do_vfs_ioctl+0x2f0/0x4f0 - SyS_ioctl+0x81/0xa0 - system_call_fastpath+0x12/0x6a - } hitcount: 17726 bytes_req: 13944120 bytes_alloc: 19593808 - { stacktrace: - __kmalloc+0x11b/0x1b0 - load_elf_phdrs+0x76/0xa0 - load_elf_binary+0x102/0x1650 - search_binary_handler+0x97/0x1d0 - do_execveat_common.isra.34+0x551/0x6e0 - SyS_execve+0x3a/0x50 - return_from_execve+0x0/0x23 - } hitcount: 33348 bytes_req: 17152128 bytes_alloc: 20226048 - { stacktrace: - kmem_cache_alloc_trace+0xeb/0x150 - apparmor_file_alloc_security+0x27/0x40 - security_file_alloc+0x16/0x20 - get_empty_filp+0x93/0x1c0 - path_openat+0x31/0x5f0 - do_filp_open+0x3a/0x90 - do_sys_open+0x128/0x220 - SyS_open+0x1e/0x20 - system_call_fastpath+0x12/0x6a - } hitcount: 4766422 bytes_req: 9532844 bytes_alloc: 38131376 - { stacktrace: - __kmalloc+0x11b/0x1b0 - seq_buf_alloc+0x1b/0x50 - seq_read+0x2cc/0x370 - proc_reg_read+0x3d/0x80 - __vfs_read+0x28/0xe0 - vfs_read+0x86/0x140 - SyS_read+0x46/0xb0 - system_call_fastpath+0x12/0x6a - } hitcount: 19133 bytes_req: 78368768 bytes_alloc: 78368768 - - Totals: - Hits: 6085872 - Entries: 253 - Dropped: 0 - - If you key a hist trigger on common_pid, in order for example to - gather and display sorted totals for each process, you can use the - special .execname modifier to display the executable names for the - processes in the table rather than raw pids. The example below - keeps a per-process sum of total bytes read:: - - # echo 'hist:key=common_pid.execname:val=count:sort=count.descending' > \ - /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger - - # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/hist - # trigger info: hist:keys=common_pid.execname:vals=count:sort=count.descending:size=2048 [active] - - { common_pid: gnome-terminal [ 3196] } hitcount: 280 count: 1093512 - { common_pid: Xorg [ 1309] } hitcount: 525 count: 256640 - { common_pid: compiz [ 2889] } hitcount: 59 count: 254400 - { common_pid: bash [ 8710] } hitcount: 3 count: 66369 - { common_pid: dbus-daemon-lau [ 8703] } hitcount: 49 count: 47739 - { common_pid: irqbalance [ 1252] } hitcount: 27 count: 27648 - { common_pid: 01ifupdown [ 8705] } hitcount: 3 count: 17216 - { common_pid: dbus-daemon [ 772] } hitcount: 10 count: 12396 - { common_pid: Socket Thread [ 8342] } hitcount: 11 count: 11264 - { common_pid: nm-dhcp-client. [ 8701] } hitcount: 6 count: 7424 - { common_pid: gmain [ 1315] } hitcount: 18 count: 6336 - . - . - . - { common_pid: postgres [ 1892] } hitcount: 2 count: 32 - { common_pid: postgres [ 1891] } hitcount: 2 count: 32 - { common_pid: gmain [ 8704] } hitcount: 2 count: 32 - { common_pid: upstart-dbus-br [ 2740] } hitcount: 21 count: 21 - { common_pid: nm-dispatcher.a [ 8696] } hitcount: 1 count: 16 - { common_pid: indicator-datet [ 2904] } hitcount: 1 count: 16 - { common_pid: gdbus [ 2998] } hitcount: 1 count: 16 - { common_pid: rtkit-daemon [ 2052] } hitcount: 1 count: 8 - { common_pid: init [ 1] } hitcount: 2 count: 2 - - Totals: - Hits: 2116 - Entries: 51 - Dropped: 0 - - Similarly, if you key a hist trigger on syscall id, for example to - gather and display a list of systemwide syscall hits, you can use - the special .syscall modifier to display the syscall names rather - than raw ids. The example below keeps a running total of syscall - counts for the system during the run:: - - # echo 'hist:key=id.syscall:val=hitcount' > \ - /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger - - # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist - # trigger info: hist:keys=id.syscall:vals=hitcount:sort=hitcount:size=2048 [active] - - { id: sys_fsync [ 74] } hitcount: 1 - { id: sys_newuname [ 63] } hitcount: 1 - { id: sys_prctl [157] } hitcount: 1 - { id: sys_statfs [137] } hitcount: 1 - { id: sys_symlink [ 88] } hitcount: 1 - { id: sys_sendmmsg [307] } hitcount: 1 - { id: sys_semctl [ 66] } hitcount: 1 - { id: sys_readlink [ 89] } hitcount: 3 - { id: sys_bind [ 49] } hitcount: 3 - { id: sys_getsockname [ 51] } hitcount: 3 - { id: sys_unlink [ 87] } hitcount: 3 - { id: sys_rename [ 82] } hitcount: 4 - { id: unknown_syscall [ 58] } hitcount: 4 - { id: sys_connect [ 42] } hitcount: 4 - { id: sys_getpid [ 39] } hitcount: 4 - . - . - . - { id: sys_rt_sigprocmask [ 14] } hitcount: 952 - { id: sys_futex [202] } hitcount: 1534 - { id: sys_write [ 1] } hitcount: 2689 - { id: sys_setitimer [ 38] } hitcount: 2797 - { id: sys_read [ 0] } hitcount: 3202 - { id: sys_select [ 23] } hitcount: 3773 - { id: sys_writev [ 20] } hitcount: 4531 - { id: sys_poll [ 7] } hitcount: 8314 - { id: sys_recvmsg [ 47] } hitcount: 13738 - { id: sys_ioctl [ 16] } hitcount: 21843 - - Totals: - Hits: 67612 - Entries: 72 - Dropped: 0 - - The syscall counts above provide a rough overall picture of system - call activity on the system; we can see for example that the most - popular system call on this system was the 'sys_ioctl' system call. - - We can use 'compound' keys to refine that number and provide some - further insight as to which processes exactly contribute to the - overall ioctl count. - - The command below keeps a hitcount for every unique combination of - system call id and pid - the end result is essentially a table - that keeps a per-pid sum of system call hits. The results are - sorted using the system call id as the primary key, and the - hitcount sum as the secondary key:: - - # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount' > \ - /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger - - # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist - # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 [active] - - { id: sys_read [ 0], common_pid: rtkit-daemon [ 1877] } hitcount: 1 - { id: sys_read [ 0], common_pid: gdbus [ 2976] } hitcount: 1 - { id: sys_read [ 0], common_pid: console-kit-dae [ 3400] } hitcount: 1 - { id: sys_read [ 0], common_pid: postgres [ 1865] } hitcount: 1 - { id: sys_read [ 0], common_pid: deja-dup-monito [ 3543] } hitcount: 2 - { id: sys_read [ 0], common_pid: NetworkManager [ 890] } hitcount: 2 - { id: sys_read [ 0], common_pid: evolution-calen [ 3048] } hitcount: 2 - { id: sys_read [ 0], common_pid: postgres [ 1864] } hitcount: 2 - { id: sys_read [ 0], common_pid: nm-applet [ 3022] } hitcount: 2 - { id: sys_read [ 0], common_pid: whoopsie [ 1212] } hitcount: 2 - . - . - . - { id: sys_ioctl [ 16], common_pid: bash [ 8479] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: bash [ 3472] } hitcount: 12 - { id: sys_ioctl [ 16], common_pid: gnome-terminal [ 3199] } hitcount: 16 - { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 1808 - { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 5580 - . - . - . - { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2690] } hitcount: 3 - { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2688] } hitcount: 16 - { id: sys_inotify_add_watch [254], common_pid: gmain [ 975] } hitcount: 2 - { id: sys_inotify_add_watch [254], common_pid: gmain [ 3204] } hitcount: 4 - { id: sys_inotify_add_watch [254], common_pid: gmain [ 2888] } hitcount: 4 - { id: sys_inotify_add_watch [254], common_pid: gmain [ 3003] } hitcount: 4 - { id: sys_inotify_add_watch [254], common_pid: gmain [ 2873] } hitcount: 4 - { id: sys_inotify_add_watch [254], common_pid: gmain [ 3196] } hitcount: 6 - { id: sys_openat [257], common_pid: java [ 2623] } hitcount: 2 - { id: sys_eventfd2 [290], common_pid: ibus-ui-gtk3 [ 2760] } hitcount: 4 - { id: sys_eventfd2 [290], common_pid: compiz [ 2994] } hitcount: 6 - - Totals: - Hits: 31536 - Entries: 323 - Dropped: 0 - - The above list does give us a breakdown of the ioctl syscall by - pid, but it also gives us quite a bit more than that, which we - don't really care about at the moment. Since we know the syscall - id for sys_ioctl (16, displayed next to the sys_ioctl name), we - can use that to filter out all the other syscalls:: - - # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount if id == 16' > \ - /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger - - # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist - # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 if id == 16 [active] - - { id: sys_ioctl [ 16], common_pid: gmain [ 2769] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: evolution-addre [ 8571] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: gmain [ 3003] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: gmain [ 2781] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: gmain [ 2829] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: bash [ 8726] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: bash [ 8508] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: gmain [ 2970] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: gmain [ 2768] } hitcount: 1 - . - . - . - { id: sys_ioctl [ 16], common_pid: pool [ 8559] } hitcount: 45 - { id: sys_ioctl [ 16], common_pid: pool [ 8555] } hitcount: 48 - { id: sys_ioctl [ 16], common_pid: pool [ 8551] } hitcount: 48 - { id: sys_ioctl [ 16], common_pid: avahi-daemon [ 896] } hitcount: 66 - { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 26674 - { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 73443 - - Totals: - Hits: 101162 - Entries: 103 - Dropped: 0 - - The above output shows that 'compiz' and 'Xorg' are far and away - the heaviest ioctl callers (which might lead to questions about - whether they really need to be making all those calls and to - possible avenues for further investigation.) - - The compound key examples used a key and a sum value (hitcount) to - sort the output, but we can just as easily use two keys instead. - Here's an example where we use a compound key composed of the the - common_pid and size event fields. Sorting with pid as the primary - key and 'size' as the secondary key allows us to display an - ordered summary of the recvfrom sizes, with counts, received by - each process:: - - # echo 'hist:key=common_pid.execname,size:val=hitcount:sort=common_pid,size' > \ - /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/trigger - - # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/hist - # trigger info: hist:keys=common_pid.execname,size:vals=hitcount:sort=common_pid.execname,size:size=2048 [active] - - { common_pid: smbd [ 784], size: 4 } hitcount: 1 - { common_pid: dnsmasq [ 1412], size: 4096 } hitcount: 672 - { common_pid: postgres [ 1796], size: 1000 } hitcount: 6 - { common_pid: postgres [ 1867], size: 1000 } hitcount: 10 - { common_pid: bamfdaemon [ 2787], size: 28 } hitcount: 2 - { common_pid: bamfdaemon [ 2787], size: 14360 } hitcount: 1 - { common_pid: compiz [ 2994], size: 8 } hitcount: 1 - { common_pid: compiz [ 2994], size: 20 } hitcount: 11 - { common_pid: gnome-terminal [ 3199], size: 4 } hitcount: 2 - { common_pid: firefox [ 8817], size: 4 } hitcount: 1 - { common_pid: firefox [ 8817], size: 8 } hitcount: 5 - { common_pid: firefox [ 8817], size: 588 } hitcount: 2 - { common_pid: firefox [ 8817], size: 628 } hitcount: 1 - { common_pid: firefox [ 8817], size: 6944 } hitcount: 1 - { common_pid: firefox [ 8817], size: 408880 } hitcount: 2 - { common_pid: firefox [ 8822], size: 8 } hitcount: 2 - { common_pid: firefox [ 8822], size: 160 } hitcount: 2 - { common_pid: firefox [ 8822], size: 320 } hitcount: 2 - { common_pid: firefox [ 8822], size: 352 } hitcount: 1 - . - . - . - { common_pid: pool [ 8923], size: 1960 } hitcount: 10 - { common_pid: pool [ 8923], size: 2048 } hitcount: 10 - { common_pid: pool [ 8924], size: 1960 } hitcount: 10 - { common_pid: pool [ 8924], size: 2048 } hitcount: 10 - { common_pid: pool [ 8928], size: 1964 } hitcount: 4 - { common_pid: pool [ 8928], size: 1965 } hitcount: 2 - { common_pid: pool [ 8928], size: 2048 } hitcount: 6 - { common_pid: pool [ 8929], size: 1982 } hitcount: 1 - { common_pid: pool [ 8929], size: 2048 } hitcount: 1 - - Totals: - Hits: 2016 - Entries: 224 - Dropped: 0 - - The above example also illustrates the fact that although a compound - key is treated as a single entity for hashing purposes, the sub-keys - it's composed of can be accessed independently. - - The next example uses a string field as the hash key and - demonstrates how you can manually pause and continue a hist trigger. - In this example, we'll aggregate fork counts and don't expect a - large number of entries in the hash table, so we'll drop it to a - much smaller number, say 256:: - - # echo 'hist:key=child_comm:val=hitcount:size=256' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger - - # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist - # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active] - - { child_comm: dconf worker } hitcount: 1 - { child_comm: ibus-daemon } hitcount: 1 - { child_comm: whoopsie } hitcount: 1 - { child_comm: smbd } hitcount: 1 - { child_comm: gdbus } hitcount: 1 - { child_comm: kthreadd } hitcount: 1 - { child_comm: dconf worker } hitcount: 1 - { child_comm: evolution-alarm } hitcount: 2 - { child_comm: Socket Thread } hitcount: 2 - { child_comm: postgres } hitcount: 2 - { child_comm: bash } hitcount: 3 - { child_comm: compiz } hitcount: 3 - { child_comm: evolution-sourc } hitcount: 4 - { child_comm: dhclient } hitcount: 4 - { child_comm: pool } hitcount: 5 - { child_comm: nm-dispatcher.a } hitcount: 8 - { child_comm: firefox } hitcount: 8 - { child_comm: dbus-daemon } hitcount: 8 - { child_comm: glib-pacrunner } hitcount: 10 - { child_comm: evolution } hitcount: 23 - - Totals: - Hits: 89 - Entries: 20 - Dropped: 0 - - If we want to pause the hist trigger, we can simply append :pause to - the command that started the trigger. Notice that the trigger info - displays as [paused]:: - - # echo 'hist:key=child_comm:val=hitcount:size=256:pause' >> \ - /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger - - # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist - # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [paused] - - { child_comm: dconf worker } hitcount: 1 - { child_comm: kthreadd } hitcount: 1 - { child_comm: dconf worker } hitcount: 1 - { child_comm: gdbus } hitcount: 1 - { child_comm: ibus-daemon } hitcount: 1 - { child_comm: Socket Thread } hitcount: 2 - { child_comm: evolution-alarm } hitcount: 2 - { child_comm: smbd } hitcount: 2 - { child_comm: bash } hitcount: 3 - { child_comm: whoopsie } hitcount: 3 - { child_comm: compiz } hitcount: 3 - { child_comm: evolution-sourc } hitcount: 4 - { child_comm: pool } hitcount: 5 - { child_comm: postgres } hitcount: 6 - { child_comm: firefox } hitcount: 8 - { child_comm: dhclient } hitcount: 10 - { child_comm: emacs } hitcount: 12 - { child_comm: dbus-daemon } hitcount: 20 - { child_comm: nm-dispatcher.a } hitcount: 20 - { child_comm: evolution } hitcount: 35 - { child_comm: glib-pacrunner } hitcount: 59 - - Totals: - Hits: 199 - Entries: 21 - Dropped: 0 - - To manually continue having the trigger aggregate events, append - :cont instead. Notice that the trigger info displays as [active] - again, and the data has changed:: - - # echo 'hist:key=child_comm:val=hitcount:size=256:cont' >> \ - /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger - - # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist - # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active] - - { child_comm: dconf worker } hitcount: 1 - { child_comm: dconf worker } hitcount: 1 - { child_comm: kthreadd } hitcount: 1 - { child_comm: gdbus } hitcount: 1 - { child_comm: ibus-daemon } hitcount: 1 - { child_comm: Socket Thread } hitcount: 2 - { child_comm: evolution-alarm } hitcount: 2 - { child_comm: smbd } hitcount: 2 - { child_comm: whoopsie } hitcount: 3 - { child_comm: compiz } hitcount: 3 - { child_comm: evolution-sourc } hitcount: 4 - { child_comm: bash } hitcount: 5 - { child_comm: pool } hitcount: 5 - { child_comm: postgres } hitcount: 6 - { child_comm: firefox } hitcount: 8 - { child_comm: dhclient } hitcount: 11 - { child_comm: emacs } hitcount: 12 - { child_comm: dbus-daemon } hitcount: 22 - { child_comm: nm-dispatcher.a } hitcount: 22 - { child_comm: evolution } hitcount: 35 - { child_comm: glib-pacrunner } hitcount: 59 - - Totals: - Hits: 206 - Entries: 21 - Dropped: 0 - - The previous example showed how to start and stop a hist trigger by - appending 'pause' and 'continue' to the hist trigger command. A - hist trigger can also be started in a paused state by initially - starting the trigger with ':pause' appended. This allows you to - start the trigger only when you're ready to start collecting data - and not before. For example, you could start the trigger in a - paused state, then unpause it and do something you want to measure, - then pause the trigger again when done. - - Of course, doing this manually can be difficult and error-prone, but - it is possible to automatically start and stop a hist trigger based - on some condition, via the enable_hist and disable_hist triggers. - - For example, suppose we wanted to take a look at the relative - weights in terms of skb length for each callpath that leads to a - netif_receieve_skb event when downloading a decent-sized file using - wget. - - First we set up an initially paused stacktrace trigger on the - netif_receive_skb event:: - - # echo 'hist:key=stacktrace:vals=len:pause' > \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - - Next, we set up an 'enable_hist' trigger on the sched_process_exec - event, with an 'if filename==/usr/bin/wget' filter. The effect of - this new trigger is that it will 'unpause' the hist trigger we just - set up on netif_receive_skb if and only if it sees a - sched_process_exec event with a filename of '/usr/bin/wget'. When - that happens, all netif_receive_skb events are aggregated into a - hash table keyed on stacktrace:: - - # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger - - The aggregation continues until the netif_receive_skb is paused - again, which is what the following disable_hist event does by - creating a similar setup on the sched_process_exit event, using the - filter 'comm==wget':: - - # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger - - Whenever a process exits and the comm field of the disable_hist - trigger filter matches 'comm==wget', the netif_receive_skb hist - trigger is disabled. - - The overall effect is that netif_receive_skb events are aggregated - into the hash table for only the duration of the wget. Executing a - wget command and then listing the 'hist' file will display the - output generated by the wget command:: - - $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz - - # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist - # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused] - - { stacktrace: - __netif_receive_skb_core+0x46d/0x990 - __netif_receive_skb+0x18/0x60 - netif_receive_skb_internal+0x23/0x90 - napi_gro_receive+0xc8/0x100 - ieee80211_deliver_skb+0xd6/0x270 [mac80211] - ieee80211_rx_handlers+0xccf/0x22f0 [mac80211] - ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211] - ieee80211_rx+0x31d/0x900 [mac80211] - iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm] - iwl_rx_dispatch+0x8e/0xf0 [iwldvm] - iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi] - irq_thread_fn+0x20/0x50 - irq_thread+0x11f/0x150 - kthread+0xd2/0xf0 - ret_from_fork+0x42/0x70 - } hitcount: 85 len: 28884 - { stacktrace: - __netif_receive_skb_core+0x46d/0x990 - __netif_receive_skb+0x18/0x60 - netif_receive_skb_internal+0x23/0x90 - napi_gro_complete+0xa4/0xe0 - dev_gro_receive+0x23a/0x360 - napi_gro_receive+0x30/0x100 - ieee80211_deliver_skb+0xd6/0x270 [mac80211] - ieee80211_rx_handlers+0xccf/0x22f0 [mac80211] - ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211] - ieee80211_rx+0x31d/0x900 [mac80211] - iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm] - iwl_rx_dispatch+0x8e/0xf0 [iwldvm] - iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi] - irq_thread_fn+0x20/0x50 - irq_thread+0x11f/0x150 - kthread+0xd2/0xf0 - } hitcount: 98 len: 664329 - { stacktrace: - __netif_receive_skb_core+0x46d/0x990 - __netif_receive_skb+0x18/0x60 - process_backlog+0xa8/0x150 - net_rx_action+0x15d/0x340 - __do_softirq+0x114/0x2c0 - do_softirq_own_stack+0x1c/0x30 - do_softirq+0x65/0x70 - __local_bh_enable_ip+0xb5/0xc0 - ip_finish_output+0x1f4/0x840 - ip_output+0x6b/0xc0 - ip_local_out_sk+0x31/0x40 - ip_send_skb+0x1a/0x50 - udp_send_skb+0x173/0x2a0 - udp_sendmsg+0x2bf/0x9f0 - inet_sendmsg+0x64/0xa0 - sock_sendmsg+0x3d/0x50 - } hitcount: 115 len: 13030 - { stacktrace: - __netif_receive_skb_core+0x46d/0x990 - __netif_receive_skb+0x18/0x60 - netif_receive_skb_internal+0x23/0x90 - napi_gro_complete+0xa4/0xe0 - napi_gro_flush+0x6d/0x90 - iwl_pcie_irq_handler+0x92a/0x12f0 [iwlwifi] - irq_thread_fn+0x20/0x50 - irq_thread+0x11f/0x150 - kthread+0xd2/0xf0 - ret_from_fork+0x42/0x70 - } hitcount: 934 len: 5512212 - - Totals: - Hits: 1232 - Entries: 4 - Dropped: 0 - - The above shows all the netif_receive_skb callpaths and their total - lengths for the duration of the wget command. - - The 'clear' hist trigger param can be used to clear the hash table. - Suppose we wanted to try another run of the previous example but - this time also wanted to see the complete list of events that went - into the histogram. In order to avoid having to set everything up - again, we can just clear the histogram first:: - - # echo 'hist:key=stacktrace:vals=len:clear' >> \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - - Just to verify that it is in fact cleared, here's what we now see in - the hist file:: - - # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist - # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused] - - Totals: - Hits: 0 - Entries: 0 - Dropped: 0 - - Since we want to see the detailed list of every netif_receive_skb - event occurring during the new run, which are in fact the same - events being aggregated into the hash table, we add some additional - 'enable_event' events to the triggering sched_process_exec and - sched_process_exit events as such:: - - # echo 'enable_event:net:netif_receive_skb if filename==/usr/bin/wget' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger - - # echo 'disable_event:net:netif_receive_skb if comm==wget' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger - - If you read the trigger files for the sched_process_exec and - sched_process_exit triggers, you should see two triggers for each: - one enabling/disabling the hist aggregation and the other - enabling/disabling the logging of events:: - - # cat /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger - enable_event:net:netif_receive_skb:unlimited if filename==/usr/bin/wget - enable_hist:net:netif_receive_skb:unlimited if filename==/usr/bin/wget - - # cat /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger - enable_event:net:netif_receive_skb:unlimited if comm==wget - disable_hist:net:netif_receive_skb:unlimited if comm==wget - - In other words, whenever either of the sched_process_exec or - sched_process_exit events is hit and matches 'wget', it enables or - disables both the histogram and the event log, and what you end up - with is a hash table and set of events just covering the specified - duration. Run the wget command again:: - - $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz - - Displaying the 'hist' file should show something similar to what you - saw in the last run, but this time you should also see the - individual events in the trace file:: - - # cat /sys/kernel/debug/tracing/trace - - # tracer: nop - # - # entries-in-buffer/entries-written: 183/1426 #P:4 - # - # _-----=> irqs-off - # / _----=> need-resched - # | / _---=> hardirq/softirq - # || / _--=> preempt-depth - # ||| / delay - # TASK-PID CPU# |||| TIMESTAMP FUNCTION - # | | | |||| | | - wget-15108 [000] ..s1 31769.606929: netif_receive_skb: dev=lo skbaddr=ffff88009c353100 len=60 - wget-15108 [000] ..s1 31769.606999: netif_receive_skb: dev=lo skbaddr=ffff88009c353200 len=60 - dnsmasq-1382 [000] ..s1 31769.677652: netif_receive_skb: dev=lo skbaddr=ffff88009c352b00 len=130 - dnsmasq-1382 [000] ..s1 31769.685917: netif_receive_skb: dev=lo skbaddr=ffff88009c352200 len=138 - ##### CPU 2 buffer started #### - irq/29-iwlwifi-559 [002] ..s. 31772.031529: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433d00 len=2948 - irq/29-iwlwifi-559 [002] ..s. 31772.031572: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432200 len=1500 - irq/29-iwlwifi-559 [002] ..s. 31772.032196: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433100 len=2948 - irq/29-iwlwifi-559 [002] ..s. 31772.032761: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433000 len=2948 - irq/29-iwlwifi-559 [002] ..s. 31772.033220: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432e00 len=1500 - .... - - - The following example demonstrates how multiple hist triggers can be - attached to a given event. This capability can be useful for - creating a set of different summaries derived from the same set of - events, or for comparing the effects of different filters, among - other things. - :: - - # echo 'hist:keys=skbaddr.hex:vals=len if len < 0' >> \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - # echo 'hist:keys=skbaddr.hex:vals=len if len > 4096' >> \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - # echo 'hist:keys=skbaddr.hex:vals=len if len == 256' >> \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - # echo 'hist:keys=skbaddr.hex:vals=len' >> \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - # echo 'hist:keys=len:vals=common_preempt_count' >> \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - - The above set of commands create four triggers differing only in - their filters, along with a completely different though fairly - nonsensical trigger. Note that in order to append multiple hist - triggers to the same file, you should use the '>>' operator to - append them ('>' will also add the new hist trigger, but will remove - any existing hist triggers beforehand). - - Displaying the contents of the 'hist' file for the event shows the - contents of all five histograms:: - - # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist - - # event histogram - # - # trigger info: hist:keys=len:vals=hitcount,common_preempt_count:sort=hitcount:size=2048 [active] - # - - { len: 176 } hitcount: 1 common_preempt_count: 0 - { len: 223 } hitcount: 1 common_preempt_count: 0 - { len: 4854 } hitcount: 1 common_preempt_count: 0 - { len: 395 } hitcount: 1 common_preempt_count: 0 - { len: 177 } hitcount: 1 common_preempt_count: 0 - { len: 446 } hitcount: 1 common_preempt_count: 0 - { len: 1601 } hitcount: 1 common_preempt_count: 0 - . - . - . - { len: 1280 } hitcount: 66 common_preempt_count: 0 - { len: 116 } hitcount: 81 common_preempt_count: 40 - { len: 708 } hitcount: 112 common_preempt_count: 0 - { len: 46 } hitcount: 221 common_preempt_count: 0 - { len: 1264 } hitcount: 458 common_preempt_count: 0 - - Totals: - Hits: 1428 - Entries: 147 - Dropped: 0 - - - # event histogram - # - # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active] - # - - { skbaddr: ffff8800baee5e00 } hitcount: 1 len: 130 - { skbaddr: ffff88005f3d5600 } hitcount: 1 len: 1280 - { skbaddr: ffff88005f3d4900 } hitcount: 1 len: 1280 - { skbaddr: ffff88009fed6300 } hitcount: 1 len: 115 - { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 115 - { skbaddr: ffff88008cdb1900 } hitcount: 1 len: 46 - { skbaddr: ffff880064b5ef00 } hitcount: 1 len: 118 - { skbaddr: ffff880044e3c700 } hitcount: 1 len: 60 - { skbaddr: ffff880100065900 } hitcount: 1 len: 46 - { skbaddr: ffff8800d46bd500 } hitcount: 1 len: 116 - { skbaddr: ffff88005f3d5f00 } hitcount: 1 len: 1280 - { skbaddr: ffff880100064700 } hitcount: 1 len: 365 - { skbaddr: ffff8800badb6f00 } hitcount: 1 len: 60 - . - . - . - { skbaddr: ffff88009fe0be00 } hitcount: 27 len: 24677 - { skbaddr: ffff88009fe0a400 } hitcount: 27 len: 23052 - { skbaddr: ffff88009fe0b700 } hitcount: 31 len: 25589 - { skbaddr: ffff88009fe0b600 } hitcount: 32 len: 27326 - { skbaddr: ffff88006a462800 } hitcount: 68 len: 71678 - { skbaddr: ffff88006a463700 } hitcount: 70 len: 72678 - { skbaddr: ffff88006a462b00 } hitcount: 71 len: 77589 - { skbaddr: ffff88006a463600 } hitcount: 73 len: 71307 - { skbaddr: ffff88006a462200 } hitcount: 81 len: 81032 - - Totals: - Hits: 1451 - Entries: 318 - Dropped: 0 - - - # event histogram - # - # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len == 256 [active] - # - - - Totals: - Hits: 0 - Entries: 0 - Dropped: 0 - - - # event histogram - # - # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len > 4096 [active] - # - - { skbaddr: ffff88009fd2c300 } hitcount: 1 len: 7212 - { skbaddr: ffff8800d2bcce00 } hitcount: 1 len: 7212 - { skbaddr: ffff8800d2bcd700 } hitcount: 1 len: 7212 - { skbaddr: ffff8800d2bcda00 } hitcount: 1 len: 21492 - { skbaddr: ffff8800ae2e2d00 } hitcount: 1 len: 7212 - { skbaddr: ffff8800d2bcdb00 } hitcount: 1 len: 7212 - { skbaddr: ffff88006a4df500 } hitcount: 1 len: 4854 - { skbaddr: ffff88008ce47b00 } hitcount: 1 len: 18636 - { skbaddr: ffff8800ae2e2200 } hitcount: 1 len: 12924 - { skbaddr: ffff88005f3e1000 } hitcount: 1 len: 4356 - { skbaddr: ffff8800d2bcdc00 } hitcount: 2 len: 24420 - { skbaddr: ffff8800d2bcc200 } hitcount: 2 len: 12996 - - Totals: - Hits: 14 - Entries: 12 - Dropped: 0 - - - # event histogram - # - # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len < 0 [active] - # - - - Totals: - Hits: 0 - Entries: 0 - Dropped: 0 - - Named triggers can be used to have triggers share a common set of - histogram data. This capability is mostly useful for combining the - output of events generated by tracepoints contained inside inline - functions, but names can be used in a hist trigger on any event. - For example, these two triggers when hit will update the same 'len' - field in the shared 'foo' histogram data:: - - # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \ - /sys/kernel/debug/tracing/events/net/netif_rx/trigger - - You can see that they're updating common histogram data by reading - each event's hist files at the same time:: - - # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist; - cat /sys/kernel/debug/tracing/events/net/netif_rx/hist - - # event histogram - # - # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active] - # - - { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46 - { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76 - { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468 - { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46 - { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52 - { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168 - { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260 - { skbaddr: ffff880064505000 } hitcount: 1 len: 46 - { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32 - { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46 - { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44 - { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168 - { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40 - { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40 - { skbaddr: ffff880064505f00 } hitcount: 1 len: 174 - { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160 - { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76 - { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32 - { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988 - { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46 - { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44 - { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676 - { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107 - { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92 - { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142 - { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220 - { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92 - { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92 - { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675 - { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138 - { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138 - { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184 - { skbaddr: ffff880064504400 } hitcount: 4 len: 184 - { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184 - { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230 - { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196 - { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276 - { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276 - - Totals: - Hits: 81 - Entries: 42 - Dropped: 0 - # event histogram - # - # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active] - # - - { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46 - { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76 - { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468 - { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46 - { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52 - { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168 - { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260 - { skbaddr: ffff880064505000 } hitcount: 1 len: 46 - { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32 - { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46 - { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44 - { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168 - { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40 - { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40 - { skbaddr: ffff880064505f00 } hitcount: 1 len: 174 - { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160 - { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76 - { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32 - { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988 - { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46 - { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44 - { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676 - { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107 - { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92 - { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142 - { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220 - { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92 - { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92 - { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675 - { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138 - { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138 - { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184 - { skbaddr: ffff880064504400 } hitcount: 4 len: 184 - { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184 - { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230 - { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196 - { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276 - { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276 - - Totals: - Hits: 81 - Entries: 42 - Dropped: 0 - - And here's an example that shows how to combine histogram data from - any two events even if they don't share any 'compatible' fields - other than 'hitcount' and 'stacktrace'. These commands create a - couple of triggers named 'bar' using those fields:: - - # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger - # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \ - /sys/kernel/debug/tracing/events/net/netif_rx/trigger - - And displaying the output of either shows some interesting if - somewhat confusing output:: - - # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist - # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist - - # event histogram - # - # trigger info: hist:name=bar:keys=stacktrace:vals=hitcount:sort=hitcount:size=2048 [active] - # - - { stacktrace: - _do_fork+0x18e/0x330 - kernel_thread+0x29/0x30 - kthreadd+0x154/0x1b0 - ret_from_fork+0x3f/0x70 - } hitcount: 1 - { stacktrace: - netif_rx_internal+0xb2/0xd0 - netif_rx_ni+0x20/0x70 - dev_loopback_xmit+0xaa/0xd0 - ip_mc_output+0x126/0x240 - ip_local_out_sk+0x31/0x40 - igmp_send_report+0x1e9/0x230 - igmp_timer_expire+0xe9/0x120 - call_timer_fn+0x39/0xf0 - run_timer_softirq+0x1e1/0x290 - __do_softirq+0xfd/0x290 - irq_exit+0x98/0xb0 - smp_apic_timer_interrupt+0x4a/0x60 - apic_timer_interrupt+0x6d/0x80 - cpuidle_enter+0x17/0x20 - call_cpuidle+0x3b/0x60 - cpu_startup_entry+0x22d/0x310 - } hitcount: 1 - { stacktrace: - netif_rx_internal+0xb2/0xd0 - netif_rx_ni+0x20/0x70 - dev_loopback_xmit+0xaa/0xd0 - ip_mc_output+0x17f/0x240 - ip_local_out_sk+0x31/0x40 - ip_send_skb+0x1a/0x50 - udp_send_skb+0x13e/0x270 - udp_sendmsg+0x2bf/0x980 - inet_sendmsg+0x67/0xa0 - sock_sendmsg+0x38/0x50 - SYSC_sendto+0xef/0x170 - SyS_sendto+0xe/0x10 - entry_SYSCALL_64_fastpath+0x12/0x6a - } hitcount: 2 - { stacktrace: - netif_rx_internal+0xb2/0xd0 - netif_rx+0x1c/0x60 - loopback_xmit+0x6c/0xb0 - dev_hard_start_xmit+0x219/0x3a0 - __dev_queue_xmit+0x415/0x4f0 - dev_queue_xmit_sk+0x13/0x20 - ip_finish_output2+0x237/0x340 - ip_finish_output+0x113/0x1d0 - ip_output+0x66/0xc0 - ip_local_out_sk+0x31/0x40 - ip_send_skb+0x1a/0x50 - udp_send_skb+0x16d/0x270 - udp_sendmsg+0x2bf/0x980 - inet_sendmsg+0x67/0xa0 - sock_sendmsg+0x38/0x50 - ___sys_sendmsg+0x14e/0x270 - } hitcount: 76 - { stacktrace: - netif_rx_internal+0xb2/0xd0 - netif_rx+0x1c/0x60 - loopback_xmit+0x6c/0xb0 - dev_hard_start_xmit+0x219/0x3a0 - __dev_queue_xmit+0x415/0x4f0 - dev_queue_xmit_sk+0x13/0x20 - ip_finish_output2+0x237/0x340 - ip_finish_output+0x113/0x1d0 - ip_output+0x66/0xc0 - ip_local_out_sk+0x31/0x40 - ip_send_skb+0x1a/0x50 - udp_send_skb+0x16d/0x270 - udp_sendmsg+0x2bf/0x980 - inet_sendmsg+0x67/0xa0 - sock_sendmsg+0x38/0x50 - ___sys_sendmsg+0x269/0x270 - } hitcount: 77 - { stacktrace: - netif_rx_internal+0xb2/0xd0 - netif_rx+0x1c/0x60 - loopback_xmit+0x6c/0xb0 - dev_hard_start_xmit+0x219/0x3a0 - __dev_queue_xmit+0x415/0x4f0 - dev_queue_xmit_sk+0x13/0x20 - ip_finish_output2+0x237/0x340 - ip_finish_output+0x113/0x1d0 - ip_output+0x66/0xc0 - ip_local_out_sk+0x31/0x40 - ip_send_skb+0x1a/0x50 - udp_send_skb+0x16d/0x270 - udp_sendmsg+0x2bf/0x980 - inet_sendmsg+0x67/0xa0 - sock_sendmsg+0x38/0x50 - SYSC_sendto+0xef/0x170 - } hitcount: 88 - { stacktrace: - _do_fork+0x18e/0x330 - SyS_clone+0x19/0x20 - entry_SYSCALL_64_fastpath+0x12/0x6a - } hitcount: 244 - - Totals: - Hits: 489 - Entries: 7 - Dropped: 0 + See Documentation/trace/histogram.txt for details and examples. diff --git a/Documentation/trace/ftrace-uses.rst b/Documentation/trace/ftrace-uses.rst index 998a60a93015..00283b6dd101 100644 --- a/Documentation/trace/ftrace-uses.rst +++ b/Documentation/trace/ftrace-uses.rst @@ -12,7 +12,7 @@ Written for: 4.14 Introduction ============ -The ftrace infrastructure was originially created to attach callbacks to the +The ftrace infrastructure was originally created to attach callbacks to the beginning of functions in order to record and trace the flow of the kernel. But callbacks to the start of a function can have other use cases. Either for live kernel patching, or for security monitoring. This document describes @@ -30,7 +30,7 @@ The ftrace context This requires extra care to what can be done inside a callback. A callback can be called outside the protective scope of RCU. -The ftrace infrastructure has some protections agains recursions and RCU +The ftrace infrastructure has some protections against recursions and RCU but one must still be very careful how they use the callbacks. diff --git a/Documentation/trace/ftrace.rst b/Documentation/trace/ftrace.rst index fdf5fb54a04c..6b80ac4bbaae 100644 --- a/Documentation/trace/ftrace.rst +++ b/Documentation/trace/ftrace.rst @@ -224,6 +224,8 @@ of ftrace. Here is a list of some of the key files: has a side effect of enabling or disabling specific functions to be traced. Echoing names of functions into this file will limit the trace to only those functions. + This influences the tracers "function" and "function_graph" + and thus also function profiling (see "function_profile_enabled"). The functions listed in "available_filter_functions" are what can be written into this file. @@ -265,6 +267,8 @@ of ftrace. Here is a list of some of the key files: Functions listed in this file will cause the function graph tracer to only trace these functions and the functions that they call. (See the section "dynamic ftrace" for more details). + Note, set_ftrace_filter and set_ftrace_notrace still affects + what functions are being traced. set_graph_notrace: @@ -277,7 +281,8 @@ of ftrace. Here is a list of some of the key files: This lists the functions that ftrace has processed and can trace. These are the function names that you can pass to - "set_ftrace_filter" or "set_ftrace_notrace". + "set_ftrace_filter", "set_ftrace_notrace", + "set_graph_function", or "set_graph_notrace". (See the section "dynamic ftrace" below for more details.) dyn_ftrace_total_info: @@ -461,9 +466,17 @@ of ftrace. Here is a list of some of the key files: and ticks at the same rate as the hardware clocksource. boot: - Same as mono. Used to be a separate clock which accounted - for the time spent in suspend while CLOCK_MONOTONIC did - not. + This is the boot clock (CLOCK_BOOTTIME) and is based on the + fast monotonic clock, but also accounts for time spent in + suspend. Since the clock access is designed for use in + tracing in the suspend path, some side effects are possible + if clock is accessed after the suspend time is accounted before + the fast mono clock is updated. In this case, the clock update + appears to happen slightly sooner than it normally would have. + Also on 32-bit systems, it's possible that the 64-bit boot offset + sees a partial update. These effects are rare and post + processing should be able to handle them. See comments in the + ktime_get_boot_fast_ns() function for more information. To set a clock, simply echo the clock name into this file:: @@ -543,6 +556,30 @@ of ftrace. Here is a list of some of the key files: See events.txt for more information. + timestamp_mode: + + Certain tracers may change the timestamp mode used when + logging trace events into the event buffer. Events with + different modes can coexist within a buffer but the mode in + effect when an event is logged determines which timestamp mode + is used for that event. The default timestamp mode is + 'delta'. + + Usual timestamp modes for tracing: + + # cat timestamp_mode + [delta] absolute + + The timestamp mode with the square brackets around it is the + one in effect. + + delta: Default timestamp mode - timestamp is a delta against + a per-buffer timestamp. + + absolute: The timestamp is a full timestamp, not a delta + against some other value. As such it takes up more + space and is less efficient. + hwlat_detector: Directory for the Hardware Latency Detector. diff --git a/Documentation/trace/histogram.txt b/Documentation/trace/histogram.txt new file mode 100644 index 000000000000..6e05510afc28 --- /dev/null +++ b/Documentation/trace/histogram.txt @@ -0,0 +1,1995 @@ + Event Histograms + + Documentation written by Tom Zanussi + +1. Introduction +=============== + + Histogram triggers are special event triggers that can be used to + aggregate trace event data into histograms. For information on + trace events and event triggers, see Documentation/trace/events.txt. + + +2. Histogram Trigger Command +============================ + + A histogram trigger command is an event trigger command that + aggregates event hits into a hash table keyed on one or more trace + event format fields (or stacktrace) and a set of running totals + derived from one or more trace event format fields and/or event + counts (hitcount). + + The format of a hist trigger is as follows: + + hist:keys=<field1[,field2,...]>[:values=<field1[,field2,...]>] + [:sort=<field1[,field2,...]>][:size=#entries][:pause][:continue] + [:clear][:name=histname1] [if <filter>] + + When a matching event is hit, an entry is added to a hash table + using the key(s) and value(s) named. Keys and values correspond to + fields in the event's format description. Values must correspond to + numeric fields - on an event hit, the value(s) will be added to a + sum kept for that field. The special string 'hitcount' can be used + in place of an explicit value field - this is simply a count of + event hits. If 'values' isn't specified, an implicit 'hitcount' + value will be automatically created and used as the only value. + Keys can be any field, or the special string 'stacktrace', which + will use the event's kernel stacktrace as the key. The keywords + 'keys' or 'key' can be used to specify keys, and the keywords + 'values', 'vals', or 'val' can be used to specify values. Compound + keys consisting of up to two fields can be specified by the 'keys' + keyword. Hashing a compound key produces a unique entry in the + table for each unique combination of component keys, and can be + useful for providing more fine-grained summaries of event data. + Additionally, sort keys consisting of up to two fields can be + specified by the 'sort' keyword. If more than one field is + specified, the result will be a 'sort within a sort': the first key + is taken to be the primary sort key and the second the secondary + key. If a hist trigger is given a name using the 'name' parameter, + its histogram data will be shared with other triggers of the same + name, and trigger hits will update this common data. Only triggers + with 'compatible' fields can be combined in this way; triggers are + 'compatible' if the fields named in the trigger share the same + number and type of fields and those fields also have the same names. + Note that any two events always share the compatible 'hitcount' and + 'stacktrace' fields and can therefore be combined using those + fields, however pointless that may be. + + 'hist' triggers add a 'hist' file to each event's subdirectory. + Reading the 'hist' file for the event will dump the hash table in + its entirety to stdout. If there are multiple hist triggers + attached to an event, there will be a table for each trigger in the + output. The table displayed for a named trigger will be the same as + any other instance having the same name. Each printed hash table + entry is a simple list of the keys and values comprising the entry; + keys are printed first and are delineated by curly braces, and are + followed by the set of value fields for the entry. By default, + numeric fields are displayed as base-10 integers. This can be + modified by appending any of the following modifiers to the field + name: + + .hex display a number as a hex value + .sym display an address as a symbol + .sym-offset display an address as a symbol and offset + .syscall display a syscall id as a system call name + .execname display a common_pid as a program name + .log2 display log2 value rather than raw number + .usecs display a common_timestamp in microseconds + + Note that in general the semantics of a given field aren't + interpreted when applying a modifier to it, but there are some + restrictions to be aware of in this regard: + + - only the 'hex' modifier can be used for values (because values + are essentially sums, and the other modifiers don't make sense + in that context). + - the 'execname' modifier can only be used on a 'common_pid'. The + reason for this is that the execname is simply the 'comm' value + saved for the 'current' process when an event was triggered, + which is the same as the common_pid value saved by the event + tracing code. Trying to apply that comm value to other pid + values wouldn't be correct, and typically events that care save + pid-specific comm fields in the event itself. + + A typical usage scenario would be the following to enable a hist + trigger, read its current contents, and then turn it off: + + # echo 'hist:keys=skbaddr.hex:vals=len' > \ + /sys/kernel/debug/tracing/events/net/netif_rx/trigger + + # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist + + # echo '!hist:keys=skbaddr.hex:vals=len' > \ + /sys/kernel/debug/tracing/events/net/netif_rx/trigger + + The trigger file itself can be read to show the details of the + currently attached hist trigger. This information is also displayed + at the top of the 'hist' file when read. + + By default, the size of the hash table is 2048 entries. The 'size' + parameter can be used to specify more or fewer than that. The units + are in terms of hashtable entries - if a run uses more entries than + specified, the results will show the number of 'drops', the number + of hits that were ignored. The size should be a power of 2 between + 128 and 131072 (any non- power-of-2 number specified will be rounded + up). + + The 'sort' parameter can be used to specify a value field to sort + on. The default if unspecified is 'hitcount' and the default sort + order is 'ascending'. To sort in the opposite direction, append + .descending' to the sort key. + + The 'pause' parameter can be used to pause an existing hist trigger + or to start a hist trigger but not log any events until told to do + so. 'continue' or 'cont' can be used to start or restart a paused + hist trigger. + + The 'clear' parameter will clear the contents of a running hist + trigger and leave its current paused/active state. + + Note that the 'pause', 'cont', and 'clear' parameters should be + applied using 'append' shell operator ('>>') if applied to an + existing trigger, rather than via the '>' operator, which will cause + the trigger to be removed through truncation. + +- enable_hist/disable_hist + + The enable_hist and disable_hist triggers can be used to have one + event conditionally start and stop another event's already-attached + hist trigger. Any number of enable_hist and disable_hist triggers + can be attached to a given event, allowing that event to kick off + and stop aggregations on a host of other events. + + The format is very similar to the enable/disable_event triggers: + + enable_hist:<system>:<event>[:count] + disable_hist:<system>:<event>[:count] + + Instead of enabling or disabling the tracing of the target event + into the trace buffer as the enable/disable_event triggers do, the + enable/disable_hist triggers enable or disable the aggregation of + the target event into a hash table. + + A typical usage scenario for the enable_hist/disable_hist triggers + would be to first set up a paused hist trigger on some event, + followed by an enable_hist/disable_hist pair that turns the hist + aggregation on and off when conditions of interest are hit: + + # echo 'hist:keys=skbaddr.hex:vals=len:pause' > \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + + # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger + + # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger + + The above sets up an initially paused hist trigger which is unpaused + and starts aggregating events when a given program is executed, and + which stops aggregating when the process exits and the hist trigger + is paused again. + + The examples below provide a more concrete illustration of the + concepts and typical usage patterns discussed above. + + 'special' event fields + ------------------------ + + There are a number of 'special event fields' available for use as + keys or values in a hist trigger. These look like and behave as if + they were actual event fields, but aren't really part of the event's + field definition or format file. They are however available for any + event, and can be used anywhere an actual event field could be. + They are: + + common_timestamp u64 - timestamp (from ring buffer) associated + with the event, in nanoseconds. May be + modified by .usecs to have timestamps + interpreted as microseconds. + cpu int - the cpu on which the event occurred. + + Extended error information + -------------------------- + + For some error conditions encountered when invoking a hist trigger + command, extended error information is available via the + corresponding event's 'hist' file. Reading the hist file after an + error will display more detailed information about what went wrong, + if information is available. This extended error information will + be available until the next hist trigger command for that event. + + If available for a given error condition, the extended error + information and usage takes the following form: + + # echo xxx > /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger + echo: write error: Invalid argument + + # cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/hist + ERROR: Couldn't yyy: zzz + Last command: xxx + +6.2 'hist' trigger examples +--------------------------- + + The first set of examples creates aggregations using the kmalloc + event. The fields that can be used for the hist trigger are listed + in the kmalloc event's format file: + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/format + name: kmalloc + ID: 374 + format: + field:unsigned short common_type; offset:0; size:2; signed:0; + field:unsigned char common_flags; offset:2; size:1; signed:0; + field:unsigned char common_preempt_count; offset:3; size:1; signed:0; + field:int common_pid; offset:4; size:4; signed:1; + + field:unsigned long call_site; offset:8; size:8; signed:0; + field:const void * ptr; offset:16; size:8; signed:0; + field:size_t bytes_req; offset:24; size:8; signed:0; + field:size_t bytes_alloc; offset:32; size:8; signed:0; + field:gfp_t gfp_flags; offset:40; size:4; signed:0; + + We'll start by creating a hist trigger that generates a simple table + that lists the total number of bytes requested for each function in + the kernel that made one or more calls to kmalloc: + + # echo 'hist:key=call_site:val=bytes_req' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + This tells the tracing system to create a 'hist' trigger using the + call_site field of the kmalloc event as the key for the table, which + just means that each unique call_site address will have an entry + created for it in the table. The 'val=bytes_req' parameter tells + the hist trigger that for each unique entry (call_site) in the + table, it should keep a running total of the number of bytes + requested by that call_site. + + We'll let it run for awhile and then dump the contents of the 'hist' + file in the kmalloc event's subdirectory (for readability, a number + of entries have been omitted): + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active] + + { call_site: 18446744072106379007 } hitcount: 1 bytes_req: 176 + { call_site: 18446744071579557049 } hitcount: 1 bytes_req: 1024 + { call_site: 18446744071580608289 } hitcount: 1 bytes_req: 16384 + { call_site: 18446744071581827654 } hitcount: 1 bytes_req: 24 + { call_site: 18446744071580700980 } hitcount: 1 bytes_req: 8 + { call_site: 18446744071579359876 } hitcount: 1 bytes_req: 152 + { call_site: 18446744071580795365 } hitcount: 3 bytes_req: 144 + { call_site: 18446744071581303129 } hitcount: 3 bytes_req: 144 + { call_site: 18446744071580713234 } hitcount: 4 bytes_req: 2560 + { call_site: 18446744071580933750 } hitcount: 4 bytes_req: 736 + . + . + . + { call_site: 18446744072106047046 } hitcount: 69 bytes_req: 5576 + { call_site: 18446744071582116407 } hitcount: 73 bytes_req: 2336 + { call_site: 18446744072106054684 } hitcount: 136 bytes_req: 140504 + { call_site: 18446744072106224230 } hitcount: 136 bytes_req: 19584 + { call_site: 18446744072106078074 } hitcount: 153 bytes_req: 2448 + { call_site: 18446744072106062406 } hitcount: 153 bytes_req: 36720 + { call_site: 18446744071582507929 } hitcount: 153 bytes_req: 37088 + { call_site: 18446744072102520590 } hitcount: 273 bytes_req: 10920 + { call_site: 18446744071582143559 } hitcount: 358 bytes_req: 716 + { call_site: 18446744072106465852 } hitcount: 417 bytes_req: 56712 + { call_site: 18446744072102523378 } hitcount: 485 bytes_req: 27160 + { call_site: 18446744072099568646 } hitcount: 1676 bytes_req: 33520 + + Totals: + Hits: 4610 + Entries: 45 + Dropped: 0 + + The output displays a line for each entry, beginning with the key + specified in the trigger, followed by the value(s) also specified in + the trigger. At the beginning of the output is a line that displays + the trigger info, which can also be displayed by reading the + 'trigger' file: + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active] + + At the end of the output are a few lines that display the overall + totals for the run. The 'Hits' field shows the total number of + times the event trigger was hit, the 'Entries' field shows the total + number of used entries in the hash table, and the 'Dropped' field + shows the number of hits that were dropped because the number of + used entries for the run exceeded the maximum number of entries + allowed for the table (normally 0, but if not a hint that you may + want to increase the size of the table using the 'size' parameter). + + Notice in the above output that there's an extra field, 'hitcount', + which wasn't specified in the trigger. Also notice that in the + trigger info output, there's a parameter, 'sort=hitcount', which + wasn't specified in the trigger either. The reason for that is that + every trigger implicitly keeps a count of the total number of hits + attributed to a given entry, called the 'hitcount'. That hitcount + information is explicitly displayed in the output, and in the + absence of a user-specified sort parameter, is used as the default + sort field. + + The value 'hitcount' can be used in place of an explicit value in + the 'values' parameter if you don't really need to have any + particular field summed and are mainly interested in hit + frequencies. + + To turn the hist trigger off, simply call up the trigger in the + command history and re-execute it with a '!' prepended: + + # echo '!hist:key=call_site:val=bytes_req' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + Finally, notice that the call_site as displayed in the output above + isn't really very useful. It's an address, but normally addresses + are displayed in hex. To have a numeric field displayed as a hex + value, simply append '.hex' to the field name in the trigger: + + # echo 'hist:key=call_site.hex:val=bytes_req' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=call_site.hex:vals=bytes_req:sort=hitcount:size=2048 [active] + + { call_site: ffffffffa026b291 } hitcount: 1 bytes_req: 433 + { call_site: ffffffffa07186ff } hitcount: 1 bytes_req: 176 + { call_site: ffffffff811ae721 } hitcount: 1 bytes_req: 16384 + { call_site: ffffffff811c5134 } hitcount: 1 bytes_req: 8 + { call_site: ffffffffa04a9ebb } hitcount: 1 bytes_req: 511 + { call_site: ffffffff8122e0a6 } hitcount: 1 bytes_req: 12 + { call_site: ffffffff8107da84 } hitcount: 1 bytes_req: 152 + { call_site: ffffffff812d8246 } hitcount: 1 bytes_req: 24 + { call_site: ffffffff811dc1e5 } hitcount: 3 bytes_req: 144 + { call_site: ffffffffa02515e8 } hitcount: 3 bytes_req: 648 + { call_site: ffffffff81258159 } hitcount: 3 bytes_req: 144 + { call_site: ffffffff811c80f4 } hitcount: 4 bytes_req: 544 + . + . + . + { call_site: ffffffffa06c7646 } hitcount: 106 bytes_req: 8024 + { call_site: ffffffffa06cb246 } hitcount: 132 bytes_req: 31680 + { call_site: ffffffffa06cef7a } hitcount: 132 bytes_req: 2112 + { call_site: ffffffff8137e399 } hitcount: 132 bytes_req: 23232 + { call_site: ffffffffa06c941c } hitcount: 185 bytes_req: 171360 + { call_site: ffffffffa06f2a66 } hitcount: 185 bytes_req: 26640 + { call_site: ffffffffa036a70e } hitcount: 265 bytes_req: 10600 + { call_site: ffffffff81325447 } hitcount: 292 bytes_req: 584 + { call_site: ffffffffa072da3c } hitcount: 446 bytes_req: 60656 + { call_site: ffffffffa036b1f2 } hitcount: 526 bytes_req: 29456 + { call_site: ffffffffa0099c06 } hitcount: 1780 bytes_req: 35600 + + Totals: + Hits: 4775 + Entries: 46 + Dropped: 0 + + Even that's only marginally more useful - while hex values do look + more like addresses, what users are typically more interested in + when looking at text addresses are the corresponding symbols + instead. To have an address displayed as symbolic value instead, + simply append '.sym' or '.sym-offset' to the field name in the + trigger: + + # echo 'hist:key=call_site.sym:val=bytes_req' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=hitcount:size=2048 [active] + + { call_site: [ffffffff810adcb9] syslog_print_all } hitcount: 1 bytes_req: 1024 + { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 + { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 + { call_site: [ffffffff8154acbe] usb_alloc_urb } hitcount: 1 bytes_req: 192 + { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 + { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40 + { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 + { call_site: [ffffffff811febd5] fsnotify_alloc_group } hitcount: 2 bytes_req: 528 + { call_site: [ffffffff81440f58] __tty_buffer_request_room } hitcount: 2 bytes_req: 2624 + { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 2 bytes_req: 96 + { call_site: [ffffffffa05e19af] ieee80211_start_tx_ba_session [mac80211] } hitcount: 2 bytes_req: 464 + { call_site: [ffffffff81672406] tcp_get_metrics } hitcount: 2 bytes_req: 304 + { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 + { call_site: [ffffffff81089b05] sched_create_group } hitcount: 2 bytes_req: 1424 + . + . + . + { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1185 bytes_req: 123240 + { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 1185 bytes_req: 104280 + { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 1402 bytes_req: 190672 + { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 1518 bytes_req: 146208 + { call_site: [ffffffffa029070e] drm_vma_node_allow [drm] } hitcount: 1746 bytes_req: 69840 + { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 2021 bytes_req: 792312 + { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 2592 bytes_req: 145152 + { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2629 bytes_req: 378576 + { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2629 bytes_req: 3783248 + { call_site: [ffffffff81325607] apparmor_file_alloc_security } hitcount: 5192 bytes_req: 10384 + { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 5529 bytes_req: 110584 + { call_site: [ffffffff8131ebf7] aa_alloc_task_context } hitcount: 21943 bytes_req: 702176 + { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 55759 bytes_req: 5074265 + + Totals: + Hits: 109928 + Entries: 71 + Dropped: 0 + + Because the default sort key above is 'hitcount', the above shows a + the list of call_sites by increasing hitcount, so that at the bottom + we see the functions that made the most kmalloc calls during the + run. If instead we we wanted to see the top kmalloc callers in + terms of the number of bytes requested rather than the number of + calls, and we wanted the top caller to appear at the top, we can use + the 'sort' parameter, along with the 'descending' modifier: + + # echo 'hist:key=call_site.sym:val=bytes_req:sort=bytes_req.descending' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=bytes_req.descending:size=2048 [active] + + { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2186 bytes_req: 3397464 + { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1790 bytes_req: 712176 + { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 8132 bytes_req: 513135 + { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 106 bytes_req: 440128 + { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2186 bytes_req: 314784 + { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 2174 bytes_req: 208992 + { call_site: [ffffffff811ae8e1] __kmalloc } hitcount: 8 bytes_req: 131072 + { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 859 bytes_req: 116824 + { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 1834 bytes_req: 102704 + { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 972 bytes_req: 101088 + { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 972 bytes_req: 85536 + { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 3333 bytes_req: 66664 + { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 209 bytes_req: 61632 + . + . + . + { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 + { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 + { call_site: [ffffffff812d8406] copy_semundo } hitcount: 2 bytes_req: 48 + { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 1 bytes_req: 48 + { call_site: [ffffffffa027121a] drm_getmagic [drm] } hitcount: 1 bytes_req: 48 + { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40 + { call_site: [ffffffff811c52f4] bprm_change_interp } hitcount: 2 bytes_req: 16 + { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 + { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 + { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 + + Totals: + Hits: 32133 + Entries: 81 + Dropped: 0 + + To display the offset and size information in addition to the symbol + name, just use 'sym-offset' instead: + + # echo 'hist:key=call_site.sym-offset:val=bytes_req:sort=bytes_req.descending' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=call_site.sym-offset:vals=bytes_req:sort=bytes_req.descending:size=2048 [active] + + { call_site: [ffffffffa046041c] i915_gem_execbuffer2+0x6c/0x2c0 [i915] } hitcount: 4569 bytes_req: 3163720 + { call_site: [ffffffffa0489a66] intel_ring_begin+0xc6/0x1f0 [i915] } hitcount: 4569 bytes_req: 657936 + { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23+0x694/0x1020 [i915] } hitcount: 1519 bytes_req: 472936 + { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23+0x516/0x1020 [i915] } hitcount: 3050 bytes_req: 211832 + { call_site: [ffffffff811e2a1b] seq_buf_alloc+0x1b/0x50 } hitcount: 34 bytes_req: 148384 + { call_site: [ffffffffa04a580c] intel_crtc_page_flip+0xbc/0x870 [i915] } hitcount: 1385 bytes_req: 144040 + { call_site: [ffffffff811ae8e1] __kmalloc+0x191/0x1b0 } hitcount: 8 bytes_req: 131072 + { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl+0x282/0x360 [drm] } hitcount: 1385 bytes_req: 121880 + { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc+0x32/0x100 [drm] } hitcount: 1848 bytes_req: 103488 + { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state+0x2c/0xa0 [i915] } hitcount: 461 bytes_req: 62696 + { call_site: [ffffffffa029070e] drm_vma_node_allow+0x2e/0xd0 [drm] } hitcount: 1541 bytes_req: 61640 + { call_site: [ffffffff815f8d7b] sk_prot_alloc+0xcb/0x1b0 } hitcount: 57 bytes_req: 57456 + . + . + . + { call_site: [ffffffff8109524a] alloc_fair_sched_group+0x5a/0x1a0 } hitcount: 2 bytes_req: 128 + { call_site: [ffffffffa027b921] drm_vm_open_locked+0x31/0xa0 [drm] } hitcount: 3 bytes_req: 96 + { call_site: [ffffffff8122e266] proc_self_follow_link+0x76/0xb0 } hitcount: 8 bytes_req: 96 + { call_site: [ffffffff81213e80] load_elf_binary+0x240/0x1650 } hitcount: 3 bytes_req: 84 + { call_site: [ffffffff8154bc62] usb_control_msg+0x42/0x110 } hitcount: 1 bytes_req: 8 + { call_site: [ffffffffa00bf6fe] hidraw_send_report+0x7e/0x1a0 [hid] } hitcount: 1 bytes_req: 7 + { call_site: [ffffffffa00bf1ca] hidraw_report_event+0x8a/0x120 [hid] } hitcount: 1 bytes_req: 7 + + Totals: + Hits: 26098 + Entries: 64 + Dropped: 0 + + We can also add multiple fields to the 'values' parameter. For + example, we might want to see the total number of bytes allocated + alongside bytes requested, and display the result sorted by bytes + allocated in a descending order: + + # echo 'hist:keys=call_site.sym:values=bytes_req,bytes_alloc:sort=bytes_alloc.descending' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=call_site.sym:vals=bytes_req,bytes_alloc:sort=bytes_alloc.descending:size=2048 [active] + + { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 7403 bytes_req: 4084360 bytes_alloc: 5958016 + { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 541 bytes_req: 2213968 bytes_alloc: 2228224 + { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 7404 bytes_req: 1066176 bytes_alloc: 1421568 + { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1565 bytes_req: 557368 bytes_alloc: 1037760 + { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 9557 bytes_req: 595778 bytes_alloc: 695744 + { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 5839 bytes_req: 430680 bytes_alloc: 470400 + { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 2388 bytes_req: 324768 bytes_alloc: 458496 + { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 3911 bytes_req: 219016 bytes_alloc: 250304 + { call_site: [ffffffff815f8d7b] sk_prot_alloc } hitcount: 235 bytes_req: 236880 bytes_alloc: 240640 + { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 557 bytes_req: 169024 bytes_alloc: 221760 + { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 9378 bytes_req: 187548 bytes_alloc: 206312 + { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1519 bytes_req: 157976 bytes_alloc: 194432 + . + . + . + { call_site: [ffffffff8109bd3b] sched_autogroup_create_attach } hitcount: 2 bytes_req: 144 bytes_alloc: 192 + { call_site: [ffffffff81097ee8] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 + { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 + { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 + { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 + { call_site: [ffffffff81213e80] load_elf_binary } hitcount: 3 bytes_req: 84 bytes_alloc: 96 + { call_site: [ffffffff81079a2e] kthread_create_on_node } hitcount: 1 bytes_req: 56 bytes_alloc: 64 + { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8 + { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 bytes_alloc: 8 + { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8 + + Totals: + Hits: 66598 + Entries: 65 + Dropped: 0 + + Finally, to finish off our kmalloc example, instead of simply having + the hist trigger display symbolic call_sites, we can have the hist + trigger additionally display the complete set of kernel stack traces + that led to each call_site. To do that, we simply use the special + value 'stacktrace' for the key parameter: + + # echo 'hist:keys=stacktrace:values=bytes_req,bytes_alloc:sort=bytes_alloc' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + The above trigger will use the kernel stack trace in effect when an + event is triggered as the key for the hash table. This allows the + enumeration of every kernel callpath that led up to a particular + event, along with a running total of any of the event fields for + that event. Here we tally bytes requested and bytes allocated for + every callpath in the system that led up to a kmalloc (in this case + every callpath to a kmalloc for a kernel compile): + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=stacktrace:vals=bytes_req,bytes_alloc:sort=bytes_alloc:size=2048 [active] + + { stacktrace: + __kmalloc_track_caller+0x10b/0x1a0 + kmemdup+0x20/0x50 + hidraw_report_event+0x8a/0x120 [hid] + hid_report_raw_event+0x3ea/0x440 [hid] + hid_input_report+0x112/0x190 [hid] + hid_irq_in+0xc2/0x260 [usbhid] + __usb_hcd_giveback_urb+0x72/0x120 + usb_giveback_urb_bh+0x9e/0xe0 + tasklet_hi_action+0xf8/0x100 + __do_softirq+0x114/0x2c0 + irq_exit+0xa5/0xb0 + do_IRQ+0x5a/0xf0 + ret_from_intr+0x0/0x30 + cpuidle_enter+0x17/0x20 + cpu_startup_entry+0x315/0x3e0 + rest_init+0x7c/0x80 + } hitcount: 3 bytes_req: 21 bytes_alloc: 24 + { stacktrace: + __kmalloc_track_caller+0x10b/0x1a0 + kmemdup+0x20/0x50 + hidraw_report_event+0x8a/0x120 [hid] + hid_report_raw_event+0x3ea/0x440 [hid] + hid_input_report+0x112/0x190 [hid] + hid_irq_in+0xc2/0x260 [usbhid] + __usb_hcd_giveback_urb+0x72/0x120 + usb_giveback_urb_bh+0x9e/0xe0 + tasklet_hi_action+0xf8/0x100 + __do_softirq+0x114/0x2c0 + irq_exit+0xa5/0xb0 + do_IRQ+0x5a/0xf0 + ret_from_intr+0x0/0x30 + } hitcount: 3 bytes_req: 21 bytes_alloc: 24 + { stacktrace: + kmem_cache_alloc_trace+0xeb/0x150 + aa_alloc_task_context+0x27/0x40 + apparmor_cred_prepare+0x1f/0x50 + security_prepare_creds+0x16/0x20 + prepare_creds+0xdf/0x1a0 + SyS_capset+0xb5/0x200 + system_call_fastpath+0x12/0x6a + } hitcount: 1 bytes_req: 32 bytes_alloc: 32 + . + . + . + { stacktrace: + __kmalloc+0x11b/0x1b0 + i915_gem_execbuffer2+0x6c/0x2c0 [i915] + drm_ioctl+0x349/0x670 [drm] + do_vfs_ioctl+0x2f0/0x4f0 + SyS_ioctl+0x81/0xa0 + system_call_fastpath+0x12/0x6a + } hitcount: 17726 bytes_req: 13944120 bytes_alloc: 19593808 + { stacktrace: + __kmalloc+0x11b/0x1b0 + load_elf_phdrs+0x76/0xa0 + load_elf_binary+0x102/0x1650 + search_binary_handler+0x97/0x1d0 + do_execveat_common.isra.34+0x551/0x6e0 + SyS_execve+0x3a/0x50 + return_from_execve+0x0/0x23 + } hitcount: 33348 bytes_req: 17152128 bytes_alloc: 20226048 + { stacktrace: + kmem_cache_alloc_trace+0xeb/0x150 + apparmor_file_alloc_security+0x27/0x40 + security_file_alloc+0x16/0x20 + get_empty_filp+0x93/0x1c0 + path_openat+0x31/0x5f0 + do_filp_open+0x3a/0x90 + do_sys_open+0x128/0x220 + SyS_open+0x1e/0x20 + system_call_fastpath+0x12/0x6a + } hitcount: 4766422 bytes_req: 9532844 bytes_alloc: 38131376 + { stacktrace: + __kmalloc+0x11b/0x1b0 + seq_buf_alloc+0x1b/0x50 + seq_read+0x2cc/0x370 + proc_reg_read+0x3d/0x80 + __vfs_read+0x28/0xe0 + vfs_read+0x86/0x140 + SyS_read+0x46/0xb0 + system_call_fastpath+0x12/0x6a + } hitcount: 19133 bytes_req: 78368768 bytes_alloc: 78368768 + + Totals: + Hits: 6085872 + Entries: 253 + Dropped: 0 + + If you key a hist trigger on common_pid, in order for example to + gather and display sorted totals for each process, you can use the + special .execname modifier to display the executable names for the + processes in the table rather than raw pids. The example below + keeps a per-process sum of total bytes read: + + # echo 'hist:key=common_pid.execname:val=count:sort=count.descending' > \ + /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger + + # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/hist + # trigger info: hist:keys=common_pid.execname:vals=count:sort=count.descending:size=2048 [active] + + { common_pid: gnome-terminal [ 3196] } hitcount: 280 count: 1093512 + { common_pid: Xorg [ 1309] } hitcount: 525 count: 256640 + { common_pid: compiz [ 2889] } hitcount: 59 count: 254400 + { common_pid: bash [ 8710] } hitcount: 3 count: 66369 + { common_pid: dbus-daemon-lau [ 8703] } hitcount: 49 count: 47739 + { common_pid: irqbalance [ 1252] } hitcount: 27 count: 27648 + { common_pid: 01ifupdown [ 8705] } hitcount: 3 count: 17216 + { common_pid: dbus-daemon [ 772] } hitcount: 10 count: 12396 + { common_pid: Socket Thread [ 8342] } hitcount: 11 count: 11264 + { common_pid: nm-dhcp-client. [ 8701] } hitcount: 6 count: 7424 + { common_pid: gmain [ 1315] } hitcount: 18 count: 6336 + . + . + . + { common_pid: postgres [ 1892] } hitcount: 2 count: 32 + { common_pid: postgres [ 1891] } hitcount: 2 count: 32 + { common_pid: gmain [ 8704] } hitcount: 2 count: 32 + { common_pid: upstart-dbus-br [ 2740] } hitcount: 21 count: 21 + { common_pid: nm-dispatcher.a [ 8696] } hitcount: 1 count: 16 + { common_pid: indicator-datet [ 2904] } hitcount: 1 count: 16 + { common_pid: gdbus [ 2998] } hitcount: 1 count: 16 + { common_pid: rtkit-daemon [ 2052] } hitcount: 1 count: 8 + { common_pid: init [ 1] } hitcount: 2 count: 2 + + Totals: + Hits: 2116 + Entries: 51 + Dropped: 0 + + Similarly, if you key a hist trigger on syscall id, for example to + gather and display a list of systemwide syscall hits, you can use + the special .syscall modifier to display the syscall names rather + than raw ids. The example below keeps a running total of syscall + counts for the system during the run: + + # echo 'hist:key=id.syscall:val=hitcount' > \ + /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger + + # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist + # trigger info: hist:keys=id.syscall:vals=hitcount:sort=hitcount:size=2048 [active] + + { id: sys_fsync [ 74] } hitcount: 1 + { id: sys_newuname [ 63] } hitcount: 1 + { id: sys_prctl [157] } hitcount: 1 + { id: sys_statfs [137] } hitcount: 1 + { id: sys_symlink [ 88] } hitcount: 1 + { id: sys_sendmmsg [307] } hitcount: 1 + { id: sys_semctl [ 66] } hitcount: 1 + { id: sys_readlink [ 89] } hitcount: 3 + { id: sys_bind [ 49] } hitcount: 3 + { id: sys_getsockname [ 51] } hitcount: 3 + { id: sys_unlink [ 87] } hitcount: 3 + { id: sys_rename [ 82] } hitcount: 4 + { id: unknown_syscall [ 58] } hitcount: 4 + { id: sys_connect [ 42] } hitcount: 4 + { id: sys_getpid [ 39] } hitcount: 4 + . + . + . + { id: sys_rt_sigprocmask [ 14] } hitcount: 952 + { id: sys_futex [202] } hitcount: 1534 + { id: sys_write [ 1] } hitcount: 2689 + { id: sys_setitimer [ 38] } hitcount: 2797 + { id: sys_read [ 0] } hitcount: 3202 + { id: sys_select [ 23] } hitcount: 3773 + { id: sys_writev [ 20] } hitcount: 4531 + { id: sys_poll [ 7] } hitcount: 8314 + { id: sys_recvmsg [ 47] } hitcount: 13738 + { id: sys_ioctl [ 16] } hitcount: 21843 + + Totals: + Hits: 67612 + Entries: 72 + Dropped: 0 + + The syscall counts above provide a rough overall picture of system + call activity on the system; we can see for example that the most + popular system call on this system was the 'sys_ioctl' system call. + + We can use 'compound' keys to refine that number and provide some + further insight as to which processes exactly contribute to the + overall ioctl count. + + The command below keeps a hitcount for every unique combination of + system call id and pid - the end result is essentially a table + that keeps a per-pid sum of system call hits. The results are + sorted using the system call id as the primary key, and the + hitcount sum as the secondary key: + + # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount' > \ + /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger + + # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist + # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 [active] + + { id: sys_read [ 0], common_pid: rtkit-daemon [ 1877] } hitcount: 1 + { id: sys_read [ 0], common_pid: gdbus [ 2976] } hitcount: 1 + { id: sys_read [ 0], common_pid: console-kit-dae [ 3400] } hitcount: 1 + { id: sys_read [ 0], common_pid: postgres [ 1865] } hitcount: 1 + { id: sys_read [ 0], common_pid: deja-dup-monito [ 3543] } hitcount: 2 + { id: sys_read [ 0], common_pid: NetworkManager [ 890] } hitcount: 2 + { id: sys_read [ 0], common_pid: evolution-calen [ 3048] } hitcount: 2 + { id: sys_read [ 0], common_pid: postgres [ 1864] } hitcount: 2 + { id: sys_read [ 0], common_pid: nm-applet [ 3022] } hitcount: 2 + { id: sys_read [ 0], common_pid: whoopsie [ 1212] } hitcount: 2 + . + . + . + { id: sys_ioctl [ 16], common_pid: bash [ 8479] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: bash [ 3472] } hitcount: 12 + { id: sys_ioctl [ 16], common_pid: gnome-terminal [ 3199] } hitcount: 16 + { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 1808 + { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 5580 + . + . + . + { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2690] } hitcount: 3 + { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2688] } hitcount: 16 + { id: sys_inotify_add_watch [254], common_pid: gmain [ 975] } hitcount: 2 + { id: sys_inotify_add_watch [254], common_pid: gmain [ 3204] } hitcount: 4 + { id: sys_inotify_add_watch [254], common_pid: gmain [ 2888] } hitcount: 4 + { id: sys_inotify_add_watch [254], common_pid: gmain [ 3003] } hitcount: 4 + { id: sys_inotify_add_watch [254], common_pid: gmain [ 2873] } hitcount: 4 + { id: sys_inotify_add_watch [254], common_pid: gmain [ 3196] } hitcount: 6 + { id: sys_openat [257], common_pid: java [ 2623] } hitcount: 2 + { id: sys_eventfd2 [290], common_pid: ibus-ui-gtk3 [ 2760] } hitcount: 4 + { id: sys_eventfd2 [290], common_pid: compiz [ 2994] } hitcount: 6 + + Totals: + Hits: 31536 + Entries: 323 + Dropped: 0 + + The above list does give us a breakdown of the ioctl syscall by + pid, but it also gives us quite a bit more than that, which we + don't really care about at the moment. Since we know the syscall + id for sys_ioctl (16, displayed next to the sys_ioctl name), we + can use that to filter out all the other syscalls: + + # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount if id == 16' > \ + /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger + + # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist + # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 if id == 16 [active] + + { id: sys_ioctl [ 16], common_pid: gmain [ 2769] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: evolution-addre [ 8571] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: gmain [ 3003] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: gmain [ 2781] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: gmain [ 2829] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: bash [ 8726] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: bash [ 8508] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: gmain [ 2970] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: gmain [ 2768] } hitcount: 1 + . + . + . + { id: sys_ioctl [ 16], common_pid: pool [ 8559] } hitcount: 45 + { id: sys_ioctl [ 16], common_pid: pool [ 8555] } hitcount: 48 + { id: sys_ioctl [ 16], common_pid: pool [ 8551] } hitcount: 48 + { id: sys_ioctl [ 16], common_pid: avahi-daemon [ 896] } hitcount: 66 + { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 26674 + { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 73443 + + Totals: + Hits: 101162 + Entries: 103 + Dropped: 0 + + The above output shows that 'compiz' and 'Xorg' are far and away + the heaviest ioctl callers (which might lead to questions about + whether they really need to be making all those calls and to + possible avenues for further investigation.) + + The compound key examples used a key and a sum value (hitcount) to + sort the output, but we can just as easily use two keys instead. + Here's an example where we use a compound key composed of the the + common_pid and size event fields. Sorting with pid as the primary + key and 'size' as the secondary key allows us to display an + ordered summary of the recvfrom sizes, with counts, received by + each process: + + # echo 'hist:key=common_pid.execname,size:val=hitcount:sort=common_pid,size' > \ + /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/trigger + + # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/hist + # trigger info: hist:keys=common_pid.execname,size:vals=hitcount:sort=common_pid.execname,size:size=2048 [active] + + { common_pid: smbd [ 784], size: 4 } hitcount: 1 + { common_pid: dnsmasq [ 1412], size: 4096 } hitcount: 672 + { common_pid: postgres [ 1796], size: 1000 } hitcount: 6 + { common_pid: postgres [ 1867], size: 1000 } hitcount: 10 + { common_pid: bamfdaemon [ 2787], size: 28 } hitcount: 2 + { common_pid: bamfdaemon [ 2787], size: 14360 } hitcount: 1 + { common_pid: compiz [ 2994], size: 8 } hitcount: 1 + { common_pid: compiz [ 2994], size: 20 } hitcount: 11 + { common_pid: gnome-terminal [ 3199], size: 4 } hitcount: 2 + { common_pid: firefox [ 8817], size: 4 } hitcount: 1 + { common_pid: firefox [ 8817], size: 8 } hitcount: 5 + { common_pid: firefox [ 8817], size: 588 } hitcount: 2 + { common_pid: firefox [ 8817], size: 628 } hitcount: 1 + { common_pid: firefox [ 8817], size: 6944 } hitcount: 1 + { common_pid: firefox [ 8817], size: 408880 } hitcount: 2 + { common_pid: firefox [ 8822], size: 8 } hitcount: 2 + { common_pid: firefox [ 8822], size: 160 } hitcount: 2 + { common_pid: firefox [ 8822], size: 320 } hitcount: 2 + { common_pid: firefox [ 8822], size: 352 } hitcount: 1 + . + . + . + { common_pid: pool [ 8923], size: 1960 } hitcount: 10 + { common_pid: pool [ 8923], size: 2048 } hitcount: 10 + { common_pid: pool [ 8924], size: 1960 } hitcount: 10 + { common_pid: pool [ 8924], size: 2048 } hitcount: 10 + { common_pid: pool [ 8928], size: 1964 } hitcount: 4 + { common_pid: pool [ 8928], size: 1965 } hitcount: 2 + { common_pid: pool [ 8928], size: 2048 } hitcount: 6 + { common_pid: pool [ 8929], size: 1982 } hitcount: 1 + { common_pid: pool [ 8929], size: 2048 } hitcount: 1 + + Totals: + Hits: 2016 + Entries: 224 + Dropped: 0 + + The above example also illustrates the fact that although a compound + key is treated as a single entity for hashing purposes, the sub-keys + it's composed of can be accessed independently. + + The next example uses a string field as the hash key and + demonstrates how you can manually pause and continue a hist trigger. + In this example, we'll aggregate fork counts and don't expect a + large number of entries in the hash table, so we'll drop it to a + much smaller number, say 256: + + # echo 'hist:key=child_comm:val=hitcount:size=256' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger + + # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist + # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active] + + { child_comm: dconf worker } hitcount: 1 + { child_comm: ibus-daemon } hitcount: 1 + { child_comm: whoopsie } hitcount: 1 + { child_comm: smbd } hitcount: 1 + { child_comm: gdbus } hitcount: 1 + { child_comm: kthreadd } hitcount: 1 + { child_comm: dconf worker } hitcount: 1 + { child_comm: evolution-alarm } hitcount: 2 + { child_comm: Socket Thread } hitcount: 2 + { child_comm: postgres } hitcount: 2 + { child_comm: bash } hitcount: 3 + { child_comm: compiz } hitcount: 3 + { child_comm: evolution-sourc } hitcount: 4 + { child_comm: dhclient } hitcount: 4 + { child_comm: pool } hitcount: 5 + { child_comm: nm-dispatcher.a } hitcount: 8 + { child_comm: firefox } hitcount: 8 + { child_comm: dbus-daemon } hitcount: 8 + { child_comm: glib-pacrunner } hitcount: 10 + { child_comm: evolution } hitcount: 23 + + Totals: + Hits: 89 + Entries: 20 + Dropped: 0 + + If we want to pause the hist trigger, we can simply append :pause to + the command that started the trigger. Notice that the trigger info + displays as [paused]: + + # echo 'hist:key=child_comm:val=hitcount:size=256:pause' >> \ + /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger + + # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist + # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [paused] + + { child_comm: dconf worker } hitcount: 1 + { child_comm: kthreadd } hitcount: 1 + { child_comm: dconf worker } hitcount: 1 + { child_comm: gdbus } hitcount: 1 + { child_comm: ibus-daemon } hitcount: 1 + { child_comm: Socket Thread } hitcount: 2 + { child_comm: evolution-alarm } hitcount: 2 + { child_comm: smbd } hitcount: 2 + { child_comm: bash } hitcount: 3 + { child_comm: whoopsie } hitcount: 3 + { child_comm: compiz } hitcount: 3 + { child_comm: evolution-sourc } hitcount: 4 + { child_comm: pool } hitcount: 5 + { child_comm: postgres } hitcount: 6 + { child_comm: firefox } hitcount: 8 + { child_comm: dhclient } hitcount: 10 + { child_comm: emacs } hitcount: 12 + { child_comm: dbus-daemon } hitcount: 20 + { child_comm: nm-dispatcher.a } hitcount: 20 + { child_comm: evolution } hitcount: 35 + { child_comm: glib-pacrunner } hitcount: 59 + + Totals: + Hits: 199 + Entries: 21 + Dropped: 0 + + To manually continue having the trigger aggregate events, append + :cont instead. Notice that the trigger info displays as [active] + again, and the data has changed: + + # echo 'hist:key=child_comm:val=hitcount:size=256:cont' >> \ + /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger + + # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist + # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active] + + { child_comm: dconf worker } hitcount: 1 + { child_comm: dconf worker } hitcount: 1 + { child_comm: kthreadd } hitcount: 1 + { child_comm: gdbus } hitcount: 1 + { child_comm: ibus-daemon } hitcount: 1 + { child_comm: Socket Thread } hitcount: 2 + { child_comm: evolution-alarm } hitcount: 2 + { child_comm: smbd } hitcount: 2 + { child_comm: whoopsie } hitcount: 3 + { child_comm: compiz } hitcount: 3 + { child_comm: evolution-sourc } hitcount: 4 + { child_comm: bash } hitcount: 5 + { child_comm: pool } hitcount: 5 + { child_comm: postgres } hitcount: 6 + { child_comm: firefox } hitcount: 8 + { child_comm: dhclient } hitcount: 11 + { child_comm: emacs } hitcount: 12 + { child_comm: dbus-daemon } hitcount: 22 + { child_comm: nm-dispatcher.a } hitcount: 22 + { child_comm: evolution } hitcount: 35 + { child_comm: glib-pacrunner } hitcount: 59 + + Totals: + Hits: 206 + Entries: 21 + Dropped: 0 + + The previous example showed how to start and stop a hist trigger by + appending 'pause' and 'continue' to the hist trigger command. A + hist trigger can also be started in a paused state by initially + starting the trigger with ':pause' appended. This allows you to + start the trigger only when you're ready to start collecting data + and not before. For example, you could start the trigger in a + paused state, then unpause it and do something you want to measure, + then pause the trigger again when done. + + Of course, doing this manually can be difficult and error-prone, but + it is possible to automatically start and stop a hist trigger based + on some condition, via the enable_hist and disable_hist triggers. + + For example, suppose we wanted to take a look at the relative + weights in terms of skb length for each callpath that leads to a + netif_receieve_skb event when downloading a decent-sized file using + wget. + + First we set up an initially paused stacktrace trigger on the + netif_receive_skb event: + + # echo 'hist:key=stacktrace:vals=len:pause' > \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + + Next, we set up an 'enable_hist' trigger on the sched_process_exec + event, with an 'if filename==/usr/bin/wget' filter. The effect of + this new trigger is that it will 'unpause' the hist trigger we just + set up on netif_receive_skb if and only if it sees a + sched_process_exec event with a filename of '/usr/bin/wget'. When + that happens, all netif_receive_skb events are aggregated into a + hash table keyed on stacktrace: + + # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger + + The aggregation continues until the netif_receive_skb is paused + again, which is what the following disable_hist event does by + creating a similar setup on the sched_process_exit event, using the + filter 'comm==wget': + + # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger + + Whenever a process exits and the comm field of the disable_hist + trigger filter matches 'comm==wget', the netif_receive_skb hist + trigger is disabled. + + The overall effect is that netif_receive_skb events are aggregated + into the hash table for only the duration of the wget. Executing a + wget command and then listing the 'hist' file will display the + output generated by the wget command: + + $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz + + # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist + # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused] + + { stacktrace: + __netif_receive_skb_core+0x46d/0x990 + __netif_receive_skb+0x18/0x60 + netif_receive_skb_internal+0x23/0x90 + napi_gro_receive+0xc8/0x100 + ieee80211_deliver_skb+0xd6/0x270 [mac80211] + ieee80211_rx_handlers+0xccf/0x22f0 [mac80211] + ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211] + ieee80211_rx+0x31d/0x900 [mac80211] + iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm] + iwl_rx_dispatch+0x8e/0xf0 [iwldvm] + iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi] + irq_thread_fn+0x20/0x50 + irq_thread+0x11f/0x150 + kthread+0xd2/0xf0 + ret_from_fork+0x42/0x70 + } hitcount: 85 len: 28884 + { stacktrace: + __netif_receive_skb_core+0x46d/0x990 + __netif_receive_skb+0x18/0x60 + netif_receive_skb_internal+0x23/0x90 + napi_gro_complete+0xa4/0xe0 + dev_gro_receive+0x23a/0x360 + napi_gro_receive+0x30/0x100 + ieee80211_deliver_skb+0xd6/0x270 [mac80211] + ieee80211_rx_handlers+0xccf/0x22f0 [mac80211] + ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211] + ieee80211_rx+0x31d/0x900 [mac80211] + iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm] + iwl_rx_dispatch+0x8e/0xf0 [iwldvm] + iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi] + irq_thread_fn+0x20/0x50 + irq_thread+0x11f/0x150 + kthread+0xd2/0xf0 + } hitcount: 98 len: 664329 + { stacktrace: + __netif_receive_skb_core+0x46d/0x990 + __netif_receive_skb+0x18/0x60 + process_backlog+0xa8/0x150 + net_rx_action+0x15d/0x340 + __do_softirq+0x114/0x2c0 + do_softirq_own_stack+0x1c/0x30 + do_softirq+0x65/0x70 + __local_bh_enable_ip+0xb5/0xc0 + ip_finish_output+0x1f4/0x840 + ip_output+0x6b/0xc0 + ip_local_out_sk+0x31/0x40 + ip_send_skb+0x1a/0x50 + udp_send_skb+0x173/0x2a0 + udp_sendmsg+0x2bf/0x9f0 + inet_sendmsg+0x64/0xa0 + sock_sendmsg+0x3d/0x50 + } hitcount: 115 len: 13030 + { stacktrace: + __netif_receive_skb_core+0x46d/0x990 + __netif_receive_skb+0x18/0x60 + netif_receive_skb_internal+0x23/0x90 + napi_gro_complete+0xa4/0xe0 + napi_gro_flush+0x6d/0x90 + iwl_pcie_irq_handler+0x92a/0x12f0 [iwlwifi] + irq_thread_fn+0x20/0x50 + irq_thread+0x11f/0x150 + kthread+0xd2/0xf0 + ret_from_fork+0x42/0x70 + } hitcount: 934 len: 5512212 + + Totals: + Hits: 1232 + Entries: 4 + Dropped: 0 + + The above shows all the netif_receive_skb callpaths and their total + lengths for the duration of the wget command. + + The 'clear' hist trigger param can be used to clear the hash table. + Suppose we wanted to try another run of the previous example but + this time also wanted to see the complete list of events that went + into the histogram. In order to avoid having to set everything up + again, we can just clear the histogram first: + + # echo 'hist:key=stacktrace:vals=len:clear' >> \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + + Just to verify that it is in fact cleared, here's what we now see in + the hist file: + + # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist + # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused] + + Totals: + Hits: 0 + Entries: 0 + Dropped: 0 + + Since we want to see the detailed list of every netif_receive_skb + event occurring during the new run, which are in fact the same + events being aggregated into the hash table, we add some additional + 'enable_event' events to the triggering sched_process_exec and + sched_process_exit events as such: + + # echo 'enable_event:net:netif_receive_skb if filename==/usr/bin/wget' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger + + # echo 'disable_event:net:netif_receive_skb if comm==wget' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger + + If you read the trigger files for the sched_process_exec and + sched_process_exit triggers, you should see two triggers for each: + one enabling/disabling the hist aggregation and the other + enabling/disabling the logging of events: + + # cat /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger + enable_event:net:netif_receive_skb:unlimited if filename==/usr/bin/wget + enable_hist:net:netif_receive_skb:unlimited if filename==/usr/bin/wget + + # cat /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger + enable_event:net:netif_receive_skb:unlimited if comm==wget + disable_hist:net:netif_receive_skb:unlimited if comm==wget + + In other words, whenever either of the sched_process_exec or + sched_process_exit events is hit and matches 'wget', it enables or + disables both the histogram and the event log, and what you end up + with is a hash table and set of events just covering the specified + duration. Run the wget command again: + + $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz + + Displaying the 'hist' file should show something similar to what you + saw in the last run, but this time you should also see the + individual events in the trace file: + + # cat /sys/kernel/debug/tracing/trace + + # tracer: nop + # + # entries-in-buffer/entries-written: 183/1426 #P:4 + # + # _-----=> irqs-off + # / _----=> need-resched + # | / _---=> hardirq/softirq + # || / _--=> preempt-depth + # ||| / delay + # TASK-PID CPU# |||| TIMESTAMP FUNCTION + # | | | |||| | | + wget-15108 [000] ..s1 31769.606929: netif_receive_skb: dev=lo skbaddr=ffff88009c353100 len=60 + wget-15108 [000] ..s1 31769.606999: netif_receive_skb: dev=lo skbaddr=ffff88009c353200 len=60 + dnsmasq-1382 [000] ..s1 31769.677652: netif_receive_skb: dev=lo skbaddr=ffff88009c352b00 len=130 + dnsmasq-1382 [000] ..s1 31769.685917: netif_receive_skb: dev=lo skbaddr=ffff88009c352200 len=138 + ##### CPU 2 buffer started #### + irq/29-iwlwifi-559 [002] ..s. 31772.031529: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433d00 len=2948 + irq/29-iwlwifi-559 [002] ..s. 31772.031572: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432200 len=1500 + irq/29-iwlwifi-559 [002] ..s. 31772.032196: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433100 len=2948 + irq/29-iwlwifi-559 [002] ..s. 31772.032761: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433000 len=2948 + irq/29-iwlwifi-559 [002] ..s. 31772.033220: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432e00 len=1500 + . + . + . + + The following example demonstrates how multiple hist triggers can be + attached to a given event. This capability can be useful for + creating a set of different summaries derived from the same set of + events, or for comparing the effects of different filters, among + other things. + + # echo 'hist:keys=skbaddr.hex:vals=len if len < 0' >> \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + # echo 'hist:keys=skbaddr.hex:vals=len if len > 4096' >> \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + # echo 'hist:keys=skbaddr.hex:vals=len if len == 256' >> \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + # echo 'hist:keys=skbaddr.hex:vals=len' >> \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + # echo 'hist:keys=len:vals=common_preempt_count' >> \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + + The above set of commands create four triggers differing only in + their filters, along with a completely different though fairly + nonsensical trigger. Note that in order to append multiple hist + triggers to the same file, you should use the '>>' operator to + append them ('>' will also add the new hist trigger, but will remove + any existing hist triggers beforehand). + + Displaying the contents of the 'hist' file for the event shows the + contents of all five histograms: + + # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist + + # event histogram + # + # trigger info: hist:keys=len:vals=hitcount,common_preempt_count:sort=hitcount:size=2048 [active] + # + + { len: 176 } hitcount: 1 common_preempt_count: 0 + { len: 223 } hitcount: 1 common_preempt_count: 0 + { len: 4854 } hitcount: 1 common_preempt_count: 0 + { len: 395 } hitcount: 1 common_preempt_count: 0 + { len: 177 } hitcount: 1 common_preempt_count: 0 + { len: 446 } hitcount: 1 common_preempt_count: 0 + { len: 1601 } hitcount: 1 common_preempt_count: 0 + . + . + . + { len: 1280 } hitcount: 66 common_preempt_count: 0 + { len: 116 } hitcount: 81 common_preempt_count: 40 + { len: 708 } hitcount: 112 common_preempt_count: 0 + { len: 46 } hitcount: 221 common_preempt_count: 0 + { len: 1264 } hitcount: 458 common_preempt_count: 0 + + Totals: + Hits: 1428 + Entries: 147 + Dropped: 0 + + + # event histogram + # + # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active] + # + + { skbaddr: ffff8800baee5e00 } hitcount: 1 len: 130 + { skbaddr: ffff88005f3d5600 } hitcount: 1 len: 1280 + { skbaddr: ffff88005f3d4900 } hitcount: 1 len: 1280 + { skbaddr: ffff88009fed6300 } hitcount: 1 len: 115 + { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 115 + { skbaddr: ffff88008cdb1900 } hitcount: 1 len: 46 + { skbaddr: ffff880064b5ef00 } hitcount: 1 len: 118 + { skbaddr: ffff880044e3c700 } hitcount: 1 len: 60 + { skbaddr: ffff880100065900 } hitcount: 1 len: 46 + { skbaddr: ffff8800d46bd500 } hitcount: 1 len: 116 + { skbaddr: ffff88005f3d5f00 } hitcount: 1 len: 1280 + { skbaddr: ffff880100064700 } hitcount: 1 len: 365 + { skbaddr: ffff8800badb6f00 } hitcount: 1 len: 60 + . + . + . + { skbaddr: ffff88009fe0be00 } hitcount: 27 len: 24677 + { skbaddr: ffff88009fe0a400 } hitcount: 27 len: 23052 + { skbaddr: ffff88009fe0b700 } hitcount: 31 len: 25589 + { skbaddr: ffff88009fe0b600 } hitcount: 32 len: 27326 + { skbaddr: ffff88006a462800 } hitcount: 68 len: 71678 + { skbaddr: ffff88006a463700 } hitcount: 70 len: 72678 + { skbaddr: ffff88006a462b00 } hitcount: 71 len: 77589 + { skbaddr: ffff88006a463600 } hitcount: 73 len: 71307 + { skbaddr: ffff88006a462200 } hitcount: 81 len: 81032 + + Totals: + Hits: 1451 + Entries: 318 + Dropped: 0 + + + # event histogram + # + # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len == 256 [active] + # + + + Totals: + Hits: 0 + Entries: 0 + Dropped: 0 + + + # event histogram + # + # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len > 4096 [active] + # + + { skbaddr: ffff88009fd2c300 } hitcount: 1 len: 7212 + { skbaddr: ffff8800d2bcce00 } hitcount: 1 len: 7212 + { skbaddr: ffff8800d2bcd700 } hitcount: 1 len: 7212 + { skbaddr: ffff8800d2bcda00 } hitcount: 1 len: 21492 + { skbaddr: ffff8800ae2e2d00 } hitcount: 1 len: 7212 + { skbaddr: ffff8800d2bcdb00 } hitcount: 1 len: 7212 + { skbaddr: ffff88006a4df500 } hitcount: 1 len: 4854 + { skbaddr: ffff88008ce47b00 } hitcount: 1 len: 18636 + { skbaddr: ffff8800ae2e2200 } hitcount: 1 len: 12924 + { skbaddr: ffff88005f3e1000 } hitcount: 1 len: 4356 + { skbaddr: ffff8800d2bcdc00 } hitcount: 2 len: 24420 + { skbaddr: ffff8800d2bcc200 } hitcount: 2 len: 12996 + + Totals: + Hits: 14 + Entries: 12 + Dropped: 0 + + + # event histogram + # + # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len < 0 [active] + # + + + Totals: + Hits: 0 + Entries: 0 + Dropped: 0 + + Named triggers can be used to have triggers share a common set of + histogram data. This capability is mostly useful for combining the + output of events generated by tracepoints contained inside inline + functions, but names can be used in a hist trigger on any event. + For example, these two triggers when hit will update the same 'len' + field in the shared 'foo' histogram data: + + # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \ + /sys/kernel/debug/tracing/events/net/netif_rx/trigger + + You can see that they're updating common histogram data by reading + each event's hist files at the same time: + + # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist; + cat /sys/kernel/debug/tracing/events/net/netif_rx/hist + + # event histogram + # + # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active] + # + + { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46 + { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76 + { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468 + { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46 + { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52 + { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168 + { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260 + { skbaddr: ffff880064505000 } hitcount: 1 len: 46 + { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32 + { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46 + { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44 + { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168 + { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40 + { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40 + { skbaddr: ffff880064505f00 } hitcount: 1 len: 174 + { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160 + { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76 + { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32 + { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988 + { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46 + { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44 + { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676 + { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107 + { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92 + { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142 + { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220 + { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92 + { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92 + { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675 + { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138 + { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138 + { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184 + { skbaddr: ffff880064504400 } hitcount: 4 len: 184 + { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184 + { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230 + { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196 + { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276 + { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276 + + Totals: + Hits: 81 + Entries: 42 + Dropped: 0 + # event histogram + # + # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active] + # + + { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46 + { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76 + { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468 + { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46 + { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52 + { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168 + { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260 + { skbaddr: ffff880064505000 } hitcount: 1 len: 46 + { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32 + { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46 + { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44 + { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168 + { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40 + { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40 + { skbaddr: ffff880064505f00 } hitcount: 1 len: 174 + { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160 + { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76 + { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32 + { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988 + { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46 + { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44 + { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676 + { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107 + { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92 + { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142 + { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220 + { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92 + { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92 + { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675 + { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138 + { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138 + { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184 + { skbaddr: ffff880064504400 } hitcount: 4 len: 184 + { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184 + { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230 + { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196 + { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276 + { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276 + + Totals: + Hits: 81 + Entries: 42 + Dropped: 0 + + And here's an example that shows how to combine histogram data from + any two events even if they don't share any 'compatible' fields + other than 'hitcount' and 'stacktrace'. These commands create a + couple of triggers named 'bar' using those fields: + + # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger + # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \ + /sys/kernel/debug/tracing/events/net/netif_rx/trigger + + And displaying the output of either shows some interesting if + somewhat confusing output: + + # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist + # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist + + # event histogram + # + # trigger info: hist:name=bar:keys=stacktrace:vals=hitcount:sort=hitcount:size=2048 [active] + # + + { stacktrace: + _do_fork+0x18e/0x330 + kernel_thread+0x29/0x30 + kthreadd+0x154/0x1b0 + ret_from_fork+0x3f/0x70 + } hitcount: 1 + { stacktrace: + netif_rx_internal+0xb2/0xd0 + netif_rx_ni+0x20/0x70 + dev_loopback_xmit+0xaa/0xd0 + ip_mc_output+0x126/0x240 + ip_local_out_sk+0x31/0x40 + igmp_send_report+0x1e9/0x230 + igmp_timer_expire+0xe9/0x120 + call_timer_fn+0x39/0xf0 + run_timer_softirq+0x1e1/0x290 + __do_softirq+0xfd/0x290 + irq_exit+0x98/0xb0 + smp_apic_timer_interrupt+0x4a/0x60 + apic_timer_interrupt+0x6d/0x80 + cpuidle_enter+0x17/0x20 + call_cpuidle+0x3b/0x60 + cpu_startup_entry+0x22d/0x310 + } hitcount: 1 + { stacktrace: + netif_rx_internal+0xb2/0xd0 + netif_rx_ni+0x20/0x70 + dev_loopback_xmit+0xaa/0xd0 + ip_mc_output+0x17f/0x240 + ip_local_out_sk+0x31/0x40 + ip_send_skb+0x1a/0x50 + udp_send_skb+0x13e/0x270 + udp_sendmsg+0x2bf/0x980 + inet_sendmsg+0x67/0xa0 + sock_sendmsg+0x38/0x50 + SYSC_sendto+0xef/0x170 + SyS_sendto+0xe/0x10 + entry_SYSCALL_64_fastpath+0x12/0x6a + } hitcount: 2 + { stacktrace: + netif_rx_internal+0xb2/0xd0 + netif_rx+0x1c/0x60 + loopback_xmit+0x6c/0xb0 + dev_hard_start_xmit+0x219/0x3a0 + __dev_queue_xmit+0x415/0x4f0 + dev_queue_xmit_sk+0x13/0x20 + ip_finish_output2+0x237/0x340 + ip_finish_output+0x113/0x1d0 + ip_output+0x66/0xc0 + ip_local_out_sk+0x31/0x40 + ip_send_skb+0x1a/0x50 + udp_send_skb+0x16d/0x270 + udp_sendmsg+0x2bf/0x980 + inet_sendmsg+0x67/0xa0 + sock_sendmsg+0x38/0x50 + ___sys_sendmsg+0x14e/0x270 + } hitcount: 76 + { stacktrace: + netif_rx_internal+0xb2/0xd0 + netif_rx+0x1c/0x60 + loopback_xmit+0x6c/0xb0 + dev_hard_start_xmit+0x219/0x3a0 + __dev_queue_xmit+0x415/0x4f0 + dev_queue_xmit_sk+0x13/0x20 + ip_finish_output2+0x237/0x340 + ip_finish_output+0x113/0x1d0 + ip_output+0x66/0xc0 + ip_local_out_sk+0x31/0x40 + ip_send_skb+0x1a/0x50 + udp_send_skb+0x16d/0x270 + udp_sendmsg+0x2bf/0x980 + inet_sendmsg+0x67/0xa0 + sock_sendmsg+0x38/0x50 + ___sys_sendmsg+0x269/0x270 + } hitcount: 77 + { stacktrace: + netif_rx_internal+0xb2/0xd0 + netif_rx+0x1c/0x60 + loopback_xmit+0x6c/0xb0 + dev_hard_start_xmit+0x219/0x3a0 + __dev_queue_xmit+0x415/0x4f0 + dev_queue_xmit_sk+0x13/0x20 + ip_finish_output2+0x237/0x340 + ip_finish_output+0x113/0x1d0 + ip_output+0x66/0xc0 + ip_local_out_sk+0x31/0x40 + ip_send_skb+0x1a/0x50 + udp_send_skb+0x16d/0x270 + udp_sendmsg+0x2bf/0x980 + inet_sendmsg+0x67/0xa0 + sock_sendmsg+0x38/0x50 + SYSC_sendto+0xef/0x170 + } hitcount: 88 + { stacktrace: + _do_fork+0x18e/0x330 + SyS_clone+0x19/0x20 + entry_SYSCALL_64_fastpath+0x12/0x6a + } hitcount: 244 + + Totals: + Hits: 489 + Entries: 7 + Dropped: 0 + + +2.2 Inter-event hist triggers +----------------------------- + +Inter-event hist triggers are hist triggers that combine values from +one or more other events and create a histogram using that data. Data +from an inter-event histogram can in turn become the source for +further combined histograms, thus providing a chain of related +histograms, which is important for some applications. + +The most important example of an inter-event quantity that can be used +in this manner is latency, which is simply a difference in timestamps +between two events. Although latency is the most important +inter-event quantity, note that because the support is completely +general across the trace event subsystem, any event field can be used +in an inter-event quantity. + +An example of a histogram that combines data from other histograms +into a useful chain would be a 'wakeupswitch latency' histogram that +combines a 'wakeup latency' histogram and a 'switch latency' +histogram. + +Normally, a hist trigger specification consists of a (possibly +compound) key along with one or more numeric values, which are +continually updated sums associated with that key. A histogram +specification in this case consists of individual key and value +specifications that refer to trace event fields associated with a +single event type. + +The inter-event hist trigger extension allows fields from multiple +events to be referenced and combined into a multi-event histogram +specification. In support of this overall goal, a few enabling +features have been added to the hist trigger support: + + - In order to compute an inter-event quantity, a value from one + event needs to saved and then referenced from another event. This + requires the introduction of support for histogram 'variables'. + + - The computation of inter-event quantities and their combination + require some minimal amount of support for applying simple + expressions to variables (+ and -). + + - A histogram consisting of inter-event quantities isn't logically a + histogram on either event (so having the 'hist' file for either + event host the histogram output doesn't really make sense). To + address the idea that the histogram is associated with a + combination of events, support is added allowing the creation of + 'synthetic' events that are events derived from other events. + These synthetic events are full-fledged events just like any other + and can be used as such, as for instance to create the + 'combination' histograms mentioned previously. + + - A set of 'actions' can be associated with histogram entries - + these can be used to generate the previously mentioned synthetic + events, but can also be used for other purposes, such as for + example saving context when a 'max' latency has been hit. + + - Trace events don't have a 'timestamp' associated with them, but + there is an implicit timestamp saved along with an event in the + underlying ftrace ring buffer. This timestamp is now exposed as a + a synthetic field named 'common_timestamp' which can be used in + histograms as if it were any other event field; it isn't an actual + field in the trace format but rather is a synthesized value that + nonetheless can be used as if it were an actual field. By default + it is in units of nanoseconds; appending '.usecs' to a + common_timestamp field changes the units to microseconds. + +A note on inter-event timestamps: If common_timestamp is used in a +histogram, the trace buffer is automatically switched over to using +absolute timestamps and the "global" trace clock, in order to avoid +bogus timestamp differences with other clocks that aren't coherent +across CPUs. This can be overridden by specifying one of the other +trace clocks instead, using the "clock=XXX" hist trigger attribute, +where XXX is any of the clocks listed in the tracing/trace_clock +pseudo-file. + +These features are described in more detail in the following sections. + +2.2.1 Histogram Variables +------------------------- + +Variables are simply named locations used for saving and retrieving +values between matching events. A 'matching' event is defined as an +event that has a matching key - if a variable is saved for a histogram +entry corresponding to that key, any subsequent event with a matching +key can access that variable. + +A variable's value is normally available to any subsequent event until +it is set to something else by a subsequent event. The one exception +to that rule is that any variable used in an expression is essentially +'read-once' - once it's used by an expression in a subsequent event, +it's reset to its 'unset' state, which means it can't be used again +unless it's set again. This ensures not only that an event doesn't +use an uninitialized variable in a calculation, but that that variable +is used only once and not for any unrelated subsequent match. + +The basic syntax for saving a variable is to simply prefix a unique +variable name not corresponding to any keyword along with an '=' sign +to any event field. + +Either keys or values can be saved and retrieved in this way. This +creates a variable named 'ts0' for a histogram entry with the key +'next_pid': + + # echo 'hist:keys=next_pid:vals=$ts0:ts0=common_timestamp ... >> \ + event/trigger + +The ts0 variable can be accessed by any subsequent event having the +same pid as 'next_pid'. + +Variable references are formed by prepending the variable name with +the '$' sign. Thus for example, the ts0 variable above would be +referenced as '$ts0' in expressions. + +Because 'vals=' is used, the common_timestamp variable value above +will also be summed as a normal histogram value would (though for a +timestamp it makes little sense). + +The below shows that a key value can also be saved in the same way: + + # echo 'hist:timer_pid=common_pid:key=timer_pid ...' >> event/trigger + +If a variable isn't a key variable or prefixed with 'vals=', the +associated event field will be saved in a variable but won't be summed +as a value: + + # echo 'hist:keys=next_pid:ts1=common_timestamp ... >> event/trigger + +Multiple variables can be assigned at the same time. The below would +result in both ts0 and b being created as variables, with both +common_timestamp and field1 additionally being summed as values: + + # echo 'hist:keys=pid:vals=$ts0,$b:ts0=common_timestamp,b=field1 ... >> \ + event/trigger + +Note that variable assignments can appear either preceding or +following their use. The command below behaves identically to the +command above: + + # echo 'hist:keys=pid:ts0=common_timestamp,b=field1:vals=$ts0,$b ... >> \ + event/trigger + +Any number of variables not bound to a 'vals=' prefix can also be +assigned by simply separating them with colons. Below is the same +thing but without the values being summed in the histogram: + + # echo 'hist:keys=pid:ts0=common_timestamp:b=field1 ... >> event/trigger + +Variables set as above can be referenced and used in expressions on +another event. + +For example, here's how a latency can be calculated: + + # echo 'hist:keys=pid,prio:ts0=common_timestamp ... >> event1/trigger + # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp-$ts0 ... >> event2/trigger + +In the first line above, the event's timetamp is saved into the +variable ts0. In the next line, ts0 is subtracted from the second +event's timestamp to produce the latency, which is then assigned into +yet another variable, 'wakeup_lat'. The hist trigger below in turn +makes use of the wakeup_lat variable to compute a combined latency +using the same key and variable from yet another event: + + # echo 'hist:key=pid:wakeupswitch_lat=$wakeup_lat+$switchtime_lat ... >> event3/trigger + +2.2.2 Synthetic Events +---------------------- + +Synthetic events are user-defined events generated from hist trigger +variables or fields associated with one or more other events. Their +purpose is to provide a mechanism for displaying data spanning +multiple events consistent with the existing and already familiar +usage for normal events. + +To define a synthetic event, the user writes a simple specification +consisting of the name of the new event along with one or more +variables and their types, which can be any valid field type, +separated by semicolons, to the tracing/synthetic_events file. + +For instance, the following creates a new event named 'wakeup_latency' +with 3 fields: lat, pid, and prio. Each of those fields is simply a +variable reference to a variable on another event: + + # echo 'wakeup_latency \ + u64 lat; \ + pid_t pid; \ + int prio' >> \ + /sys/kernel/debug/tracing/synthetic_events + +Reading the tracing/synthetic_events file lists all the currently +defined synthetic events, in this case the event defined above: + + # cat /sys/kernel/debug/tracing/synthetic_events + wakeup_latency u64 lat; pid_t pid; int prio + +An existing synthetic event definition can be removed by prepending +the command that defined it with a '!': + + # echo '!wakeup_latency u64 lat pid_t pid int prio' >> \ + /sys/kernel/debug/tracing/synthetic_events + +At this point, there isn't yet an actual 'wakeup_latency' event +instantiated in the event subsytem - for this to happen, a 'hist +trigger action' needs to be instantiated and bound to actual fields +and variables defined on other events (see Section 6.3.3 below). + +Once that is done, an event instance is created, and a histogram can +be defined using it: + + # echo 'hist:keys=pid,prio,lat.log2:sort=pid,lat' >> \ + /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/trigger + +The new event is created under the tracing/events/synthetic/ directory +and looks and behaves just like any other event: + + # ls /sys/kernel/debug/tracing/events/synthetic/wakeup_latency + enable filter format hist id trigger + +Like any other event, once a histogram is enabled for the event, the +output can be displayed by reading the event's 'hist' file. + +2.2.3 Hist trigger 'actions' +---------------------------- + +A hist trigger 'action' is a function that's executed whenever a +histogram entry is added or updated. + +The default 'action' if no special function is explicity specified is +as it always has been, to simply update the set of values associated +with an entry. Some applications, however, may want to perform +additional actions at that point, such as generate another event, or +compare and save a maximum. + +The following additional actions are available. To specify an action +for a given event, simply specify the action between colons in the +hist trigger specification. + + - onmatch(matching.event).<synthetic_event_name>(param list) + + The 'onmatch(matching.event).<synthetic_event_name>(params)' hist + trigger action is invoked whenever an event matches and the + histogram entry would be added or updated. It causes the named + synthetic event to be generated with the values given in the + 'param list'. The result is the generation of a synthetic event + that consists of the values contained in those variables at the + time the invoking event was hit. + + The 'param list' consists of one or more parameters which may be + either variables or fields defined on either the 'matching.event' + or the target event. The variables or fields specified in the + param list may be either fully-qualified or unqualified. If a + variable is specified as unqualified, it must be unique between + the two events. A field name used as a param can be unqualified + if it refers to the target event, but must be fully qualified if + it refers to the matching event. A fully-qualified name is of the + form 'system.event_name.$var_name' or 'system.event_name.field'. + + The 'matching.event' specification is simply the fully qualified + event name of the event that matches the target event for the + onmatch() functionality, in the form 'system.event_name'. + + Finally, the number and type of variables/fields in the 'param + list' must match the number and types of the fields in the + synthetic event being generated. + + As an example the below defines a simple synthetic event and uses + a variable defined on the sched_wakeup_new event as a parameter + when invoking the synthetic event. Here we define the synthetic + event: + + # echo 'wakeup_new_test pid_t pid' >> \ + /sys/kernel/debug/tracing/synthetic_events + + # cat /sys/kernel/debug/tracing/synthetic_events + wakeup_new_test pid_t pid + + The following hist trigger both defines the missing testpid + variable and specifies an onmatch() action that generates a + wakeup_new_test synthetic event whenever a sched_wakeup_new event + occurs, which because of the 'if comm == "cyclictest"' filter only + happens when the executable is cyclictest: + + # echo 'hist:keys=$testpid:testpid=pid:onmatch(sched.sched_wakeup_new).\ + wakeup_new_test($testpid) if comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_wakeup_new/trigger + + Creating and displaying a histogram based on those events is now + just a matter of using the fields and new synthetic event in the + tracing/events/synthetic directory, as usual: + + # echo 'hist:keys=pid:sort=pid' >> \ + /sys/kernel/debug/tracing/events/synthetic/wakeup_new_test/trigger + + Running 'cyclictest' should cause wakeup_new events to generate + wakeup_new_test synthetic events which should result in histogram + output in the wakeup_new_test event's hist file: + + # cat /sys/kernel/debug/tracing/events/synthetic/wakeup_new_test/hist + + A more typical usage would be to use two events to calculate a + latency. The following example uses a set of hist triggers to + produce a 'wakeup_latency' histogram: + + First, we define a 'wakeup_latency' synthetic event: + + # echo 'wakeup_latency u64 lat; pid_t pid; int prio' >> \ + /sys/kernel/debug/tracing/synthetic_events + + Next, we specify that whenever we see a sched_waking event for a + cyclictest thread, save the timestamp in a 'ts0' variable: + + # echo 'hist:keys=$saved_pid:saved_pid=pid:ts0=common_timestamp.usecs \ + if comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_waking/trigger + + Then, when the corresponding thread is actually scheduled onto the + CPU by a sched_switch event, calculate the latency and use that + along with another variable and an event field to generate a + wakeup_latency synthetic event: + + # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:\ + onmatch(sched.sched_waking).wakeup_latency($wakeup_lat,\ + $saved_pid,next_prio) if next_comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_switch/trigger + + We also need to create a histogram on the wakeup_latency synthetic + event in order to aggregate the generated synthetic event data: + + # echo 'hist:keys=pid,prio,lat:sort=pid,lat' >> \ + /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/trigger + + Finally, once we've run cyclictest to actually generate some + events, we can see the output by looking at the wakeup_latency + synthetic event's hist file: + + # cat /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/hist + + - onmax(var).save(field,.. .) + + The 'onmax(var).save(field,...)' hist trigger action is invoked + whenever the value of 'var' associated with a histogram entry + exceeds the current maximum contained in that variable. + + The end result is that the trace event fields specified as the + onmax.save() params will be saved if 'var' exceeds the current + maximum for that hist trigger entry. This allows context from the + event that exhibited the new maximum to be saved for later + reference. When the histogram is displayed, additional fields + displaying the saved values will be printed. + + As an example the below defines a couple of hist triggers, one for + sched_waking and another for sched_switch, keyed on pid. Whenever + a sched_waking occurs, the timestamp is saved in the entry + corresponding to the current pid, and when the scheduler switches + back to that pid, the timestamp difference is calculated. If the + resulting latency, stored in wakeup_lat, exceeds the current + maximum latency, the values specified in the save() fields are + recoreded: + + # echo 'hist:keys=pid:ts0=common_timestamp.usecs \ + if comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_waking/trigger + + # echo 'hist:keys=next_pid:\ + wakeup_lat=common_timestamp.usecs-$ts0:\ + onmax($wakeup_lat).save(next_comm,prev_pid,prev_prio,prev_comm) \ + if next_comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_switch/trigger + + When the histogram is displayed, the max value and the saved + values corresponding to the max are displayed following the rest + of the fields: + + # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist + { next_pid: 2255 } hitcount: 239 + common_timestamp-ts0: 0 + max: 27 + next_comm: cyclictest + prev_pid: 0 prev_prio: 120 prev_comm: swapper/1 + + { next_pid: 2256 } hitcount: 2355 + common_timestamp-ts0: 0 + max: 49 next_comm: cyclictest + prev_pid: 0 prev_prio: 120 prev_comm: swapper/0 + + Totals: + Hits: 12970 + Entries: 2 + Dropped: 0 diff --git a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl index ba976805853a..66bfd8396877 100644 --- a/Documentation/trace/postprocess/trace-vmscan-postprocess.pl +++ b/Documentation/trace/postprocess/trace-vmscan-postprocess.pl @@ -111,7 +111,7 @@ my $regex_direct_begin_default = 'order=([0-9]*) may_writepage=([0-9]*) gfp_flag my $regex_direct_end_default = 'nr_reclaimed=([0-9]*)'; my $regex_kswapd_wake_default = 'nid=([0-9]*) order=([0-9]*)'; my $regex_kswapd_sleep_default = 'nid=([0-9]*)'; -my $regex_wakeup_kswapd_default = 'nid=([0-9]*) zid=([0-9]*) order=([0-9]*)'; +my $regex_wakeup_kswapd_default = 'nid=([0-9]*) zid=([0-9]*) order=([0-9]*) gfp_flags=([A-Z_|]*)'; my $regex_lru_isolate_default = 'isolate_mode=([0-9]*) classzone_idx=([0-9]*) order=([0-9]*) nr_requested=([0-9]*) nr_scanned=([0-9]*) nr_skipped=([0-9]*) nr_taken=([0-9]*) lru=([a-z_]*)'; my $regex_lru_shrink_inactive_default = 'nid=([0-9]*) nr_scanned=([0-9]*) nr_reclaimed=([0-9]*) nr_dirty=([0-9]*) nr_writeback=([0-9]*) nr_congested=([0-9]*) nr_immediate=([0-9]*) nr_activate=([0-9]*) nr_ref_keep=([0-9]*) nr_unmap_fail=([0-9]*) priority=([0-9]*) flags=([A-Z_|]*)'; my $regex_lru_shrink_active_default = 'lru=([A-Z_]*) nr_scanned=([0-9]*) nr_rotated=([0-9]*) priority=([0-9]*)'; @@ -201,7 +201,7 @@ $regex_kswapd_sleep = generate_traceevent_regex( $regex_wakeup_kswapd = generate_traceevent_regex( "vmscan/mm_vmscan_wakeup_kswapd", $regex_wakeup_kswapd_default, - "nid", "zid", "order"); + "nid", "zid", "order", "gfp_flags"); $regex_lru_isolate = generate_traceevent_regex( "vmscan/mm_vmscan_lru_isolate", $regex_lru_isolate_default, diff --git a/Documentation/translations/ko_KR/memory-barriers.txt b/Documentation/translations/ko_KR/memory-barriers.txt index 0a0930ab4156..921739d00f69 100644 --- a/Documentation/translations/ko_KR/memory-barriers.txt +++ b/Documentation/translations/ko_KR/memory-barriers.txt @@ -36,6 +36,9 @@ Documentation/memory-barriers.txt 부분도 있고, 의도하진 않았지만 사람에 의해 쓰였다보니 불완전한 부분도 있습니다. 이 문서는 리눅스에서 제공하는 다양한 메모리 배리어들을 사용하기 위한 안내서입니다만, 뭔가 이상하다 싶으면 (그런게 많을 겁니다) 질문을 부탁드립니다. +일부 이상한 점들은 공식적인 메모리 일관성 모델과 tools/memory-model/ 에 있는 +관련 문서를 참고해서 해결될 수 있을 겁니다. 그러나, 이 메모리 모델조차도 그 +관리자들의 의견의 집합으로 봐야지, 절대 옳은 예언자로 신봉해선 안될 겁니다. 다시 말하지만, 이 문서는 리눅스가 하드웨어에 기대하는 사항에 대한 명세서가 아닙니다. @@ -77,7 +80,7 @@ Documentation/memory-barriers.txt - 메모리 배리어의 종류. - 메모리 배리어에 대해 가정해선 안될 것. - - 데이터 의존성 배리어. + - 데이터 의존성 배리어 (역사적). - 컨트롤 의존성. - SMP 배리어 짝맞추기. - 메모리 배리어 시퀀스의 예. @@ -255,17 +258,20 @@ CPU 에게 기대할 수 있는 최소한의 보장사항 몇가지가 있습니 (*) 어떤 CPU 든, 의존성이 존재하는 메모리 액세스들은 해당 CPU 자신에게 있어서는 순서대로 메모리 시스템에 수행 요청됩니다. 즉, 다음에 대해서: - Q = READ_ONCE(P); smp_read_barrier_depends(); D = READ_ONCE(*Q); + Q = READ_ONCE(P); D = READ_ONCE(*Q); CPU 는 다음과 같은 메모리 오퍼레이션 시퀀스를 수행 요청합니다: Q = LOAD P, D = LOAD *Q - 그리고 그 시퀀스 내에서의 순서는 항상 지켜집니다. 대부분의 시스템에서 - smp_read_barrier_depends() 는 아무일도 안하지만 DEC Alpha 에서는 - 명시적으로 사용되어야 합니다. 보통의 경우에는 smp_read_barrier_depends() - 를 직접 사용하는 대신 rcu_dereference() 같은 것들을 사용해야 함을 - 알아두세요. + 그리고 그 시퀀스 내에서의 순서는 항상 지켜집니다. 하지만, DEC Alpha 에서 + READ_ONCE() 는 메모리 배리어 명령도 내게 되어 있어서, DEC Alpha CPU 는 + 다음과 같은 메모리 오퍼레이션들을 내놓게 됩니다: + + Q = LOAD P, MEMORY_BARRIER, D = LOAD *Q, MEMORY_BARRIER + + DEC Alpha 에서 수행되든 아니든, READ_ONCE() 는 컴파일러로부터의 악영향 + 또한 제거합니다. (*) 특정 CPU 내에서 겹치는 영역의 메모리에 행해지는 로드와 스토어 들은 해당 CPU 안에서는 순서가 바뀌지 않은 것으로 보여집니다. 즉, 다음에 대해서: @@ -421,8 +427,8 @@ CPU 에게 기대할 수 있는 최소한의 보장사항 몇가지가 있습니 데이터 의존성 배리어는 읽기 배리어의 보다 완화된 형태입니다. 두개의 로드 오퍼레이션이 있고 두번째 것이 첫번째 것의 결과에 의존하고 있을 때(예: 두번째 로드가 참조할 주소를 첫번째 로드가 읽는 경우), 두번째 로드가 읽어올 - 데이터는 첫번째 로드에 의해 그 주소가 얻어지기 전에 업데이트 되어 있음을 - 보장하기 위해서 데이터 의존성 배리어가 필요할 수 있습니다. + 데이터는 첫번째 로드에 의해 그 주소가 얻어진 뒤에 업데이트 됨을 보장하기 + 위해서 데이터 의존성 배리어가 필요할 수 있습니다. 데이터 의존성 배리어는 상호 의존적인 로드 오퍼레이션들 사이의 부분적 순서 세우기입니다; 스토어 오퍼레이션들이나 독립적인 로드들, 또는 중복되는 @@ -570,8 +576,14 @@ ACQUIRE 는 해당 오퍼레이션의 로드 부분에만 적용되고 RELEASE Documentation/DMA-API.txt -데이터 의존성 배리어 --------------------- +데이터 의존성 배리어 (역사적) +----------------------------- + +리눅스 커널 v4.15 기준으로, smp_read_barrier_depends() 가 READ_ONCE() 에 +추가되었는데, 이는 이 섹션에 주의를 기울여야 하는 사람들은 DEC Alpha 아키텍쳐 +전용 코드를 만드는 사람들과 READ_ONCE() 자체를 만드는 사람들 뿐임을 의미합니다. +그런 분들을 위해, 그리고 역사에 관심 있는 분들을 위해, 여기 데이터 의존성 +배리어에 대한 이야기를 적습니다. 데이터 의존성 배리어의 사용에 있어 지켜야 하는 사항들은 약간 미묘하고, 데이터 의존성 배리어가 사용되어야 하는 상황도 항상 명백하지는 않습니다. 설명을 위해 @@ -1787,7 +1799,7 @@ CPU 메모리 배리어 범용 mb() smp_mb() 쓰기 wmb() smp_wmb() 읽기 rmb() smp_rmb() - 데이터 의존성 read_barrier_depends() smp_read_barrier_depends() + 데이터 의존성 READ_ONCE() 데이터 의존성 배리어를 제외한 모든 메모리 배리어는 컴파일러 배리어를 @@ -2796,8 +2808,9 @@ CPU 2 는 C/D 를 갖습니다)가 병렬로 연결되어 있는 시스템을 여기에 개입하기 위해선, 데이터 의존성 배리어나 읽기 배리어를 로드 오퍼레이션들 -사이에 넣어야 합니다. 이렇게 함으로써 캐시가 다음 요청을 처리하기 전에 일관성 -큐를 처리하도록 강제하게 됩니다. +사이에 넣어야 합니다 (v4.15 부터는 READ_ONCE() 매크로에 의해 무조건적으로 +그렇게 됩니다). 이렇게 함으로써 캐시가 다음 요청을 처리하기 전에 일관성 큐를 +처리하도록 강제하게 됩니다. CPU 1 CPU 2 COMMENT =============== =============== ======================================= @@ -2826,7 +2839,10 @@ CPU 2 는 C/D 를 갖습니다)가 병렬로 연결되어 있는 시스템을 다른 CPU 들도 분할된 캐시를 가지고 있을 수 있지만, 그런 CPU 들은 평범한 메모리 액세스를 위해서도 이 분할된 캐시들 사이의 조정을 해야만 합니다. Alpha 는 가장 약한 메모리 순서 시맨틱 (semantic) 을 선택함으로써 메모리 배리어가 명시적으로 -사용되지 않았을 때에는 그런 조정이 필요하지 않게 했습니다. +사용되지 않았을 때에는 그런 조정이 필요하지 않게 했으며, 이는 Alpha 가 당시에 +더 높은 CPU 클락 속도를 가질 수 있게 했습니다. 하지만, (다시 말하건대, v4.15 +이후부터는) Alpha 아키텍쳐 전용 코드와 READ_ONCE() 매크로 내부에서를 제외하고는 +smp_read_barrier_depends() 가 사용되지 않아야 함을 알아두시기 바랍니다. 캐시 일관성 VS DMA @@ -2846,7 +2862,7 @@ CPU 의 캐시에서 RAM 으로 쓰여지는 더티 캐시 라인에 의해 덮 문제를 해결하기 위해선, 커널의 적절한 부분에서 각 CPU 의 캐시 안의 문제가 되는 비트들을 무효화 시켜야 합니다. -캐시 관리에 대한 더 많은 정보를 위해선 Documentation/cachetlb.txt 를 +캐시 관리에 대한 더 많은 정보를 위해선 Documentation/core-api/cachetlb.rst 를 참고하세요. @@ -2988,7 +3004,9 @@ Alpha CPU 의 일부 버전은 분할된 데이터 캐시를 가지고 있어서 메모리 일관성 시스템과 함께 두개의 캐시를 동기화 시켜서, 포인터 변경과 새로운 데이터의 발견을 올바른 순서로 일어나게 하기 때문입니다. -리눅스 커널의 메모리 배리어 모델은 Alpha 에 기초해서 정의되었습니다. +리눅스 커널의 메모리 배리어 모델은 Alpha 에 기초해서 정의되었습니다만, v4.15 +부터는 리눅스 커널이 READ_ONCE() 내에 smp_read_barrier_depends() 를 추가해서 +Alpha 의 메모리 모델로의 영향력이 크게 줄어들긴 했습니다. 위의 "캐시 일관성" 서브섹션을 참고하세요. @@ -3023,7 +3041,7 @@ smp_mb() 가 아니라 virt_mb() 를 사용해야 합니다. 동기화에 락을 사용하지 않고 구현하는데에 사용될 수 있습니다. 더 자세한 내용을 위해선 다음을 참고하세요: - Documentation/circular-buffers.txt + Documentation/core-api/circular-buffers.rst ========= diff --git a/Documentation/translations/zh_CN/video4linux/v4l2-framework.txt b/Documentation/translations/zh_CN/video4linux/v4l2-framework.txt index 698660b7f21f..c77c0f060864 100644 --- a/Documentation/translations/zh_CN/video4linux/v4l2-framework.txt +++ b/Documentation/translations/zh_CN/video4linux/v4l2-framework.txt @@ -6,7 +6,7 @@ communicating in English you can also ask the Chinese maintainer for help. Contact the Chinese maintainer if this translation is outdated or if there is a problem with the translation. -Maintainer: Mauro Carvalho Chehab <mchehab@infradead.org> +Maintainer: Mauro Carvalho Chehab <mchehab@kernel.org> Chinese maintainer: Fu Wei <tekkamanninja@gmail.com> --------------------------------------------------------------------- Documentation/video4linux/v4l2-framework.txt 的中文翻译 @@ -14,7 +14,7 @@ Documentation/video4linux/v4l2-framework.txt 的中文翻译 如果想评论或更新本文的内容，请直接联系原文档的维护者。如果你使用英文 交流有困难的话，也可以向中文版维护者求助。如果本翻译更新不及时或者翻 译存在问题，请联系中文版维护者。 -英文版维护者： Mauro Carvalho Chehab <mchehab@infradead.org> +英文版维护者： Mauro Carvalho Chehab <mchehab@kernel.org> 中文版维护者： 傅炜 Fu Wei <tekkamanninja@gmail.com> 中文版翻译者： 傅炜 Fu Wei <tekkamanninja@gmail.com> 中文版校译者： 傅炜 Fu Wei <tekkamanninja@gmail.com> diff --git a/Documentation/userspace-api/index.rst b/Documentation/userspace-api/index.rst index 7b2eb1b7d4ca..a3233da7fa88 100644 --- a/Documentation/userspace-api/index.rst +++ b/Documentation/userspace-api/index.rst @@ -19,6 +19,7 @@ place where this information is gathered. no_new_privs seccomp_filter unshare + spec_ctrl .. only:: subproject and html diff --git a/Documentation/userspace-api/spec_ctrl.rst b/Documentation/userspace-api/spec_ctrl.rst new file mode 100644 index 000000000000..32f3d55c54b7 --- /dev/null +++ b/Documentation/userspace-api/spec_ctrl.rst @@ -0,0 +1,94 @@ +=================== +Speculation Control +=================== + +Quite some CPUs have speculation-related misfeatures which are in +fact vulnerabilities causing data leaks in various forms even across +privilege domains. + +The kernel provides mitigation for such vulnerabilities in various +forms. Some of these mitigations are compile-time configurable and some +can be supplied on the kernel command line. + +There is also a class of mitigations which are very expensive, but they can +be restricted to a certain set of processes or tasks in controlled +environments. The mechanism to control these mitigations is via +:manpage:`prctl(2)`. + +There are two prctl options which are related to this: + + * PR_GET_SPECULATION_CTRL + + * PR_SET_SPECULATION_CTRL + +PR_GET_SPECULATION_CTRL +----------------------- + +PR_GET_SPECULATION_CTRL returns the state of the speculation misfeature +which is selected with arg2 of prctl(2). The return value uses bits 0-3 with +the following meaning: + +==== ===================== =================================================== +Bit Define Description +==== ===================== =================================================== +0 PR_SPEC_PRCTL Mitigation can be controlled per task by + PR_SET_SPECULATION_CTRL. +1 PR_SPEC_ENABLE The speculation feature is enabled, mitigation is + disabled. +2 PR_SPEC_DISABLE The speculation feature is disabled, mitigation is + enabled. +3 PR_SPEC_FORCE_DISABLE Same as PR_SPEC_DISABLE, but cannot be undone. A + subsequent prctl(..., PR_SPEC_ENABLE) will fail. +==== ===================== =================================================== + +If all bits are 0 the CPU is not affected by the speculation misfeature. + +If PR_SPEC_PRCTL is set, then the per-task control of the mitigation is +available. If not set, prctl(PR_SET_SPECULATION_CTRL) for the speculation +misfeature will fail. + +PR_SET_SPECULATION_CTRL +----------------------- + +PR_SET_SPECULATION_CTRL allows to control the speculation misfeature, which +is selected by arg2 of :manpage:`prctl(2)` per task. arg3 is used to hand +in the control value, i.e. either PR_SPEC_ENABLE or PR_SPEC_DISABLE or +PR_SPEC_FORCE_DISABLE. + +Common error codes +------------------ +======= ================================================================= +Value Meaning +======= ================================================================= +EINVAL The prctl is not implemented by the architecture or unused + prctl(2) arguments are not 0. + +ENODEV arg2 is selecting a not supported speculation misfeature. +======= ================================================================= + +PR_SET_SPECULATION_CTRL error codes +----------------------------------- +======= ================================================================= +Value Meaning +======= ================================================================= +0 Success + +ERANGE arg3 is incorrect, i.e. it's neither PR_SPEC_ENABLE nor + PR_SPEC_DISABLE nor PR_SPEC_FORCE_DISABLE. + +ENXIO Control of the selected speculation misfeature is not possible. + See PR_GET_SPECULATION_CTRL. + +EPERM Speculation was disabled with PR_SPEC_FORCE_DISABLE and caller + tried to enable it again. +======= ================================================================= + +Speculation misfeature controls +------------------------------- +- PR_SPEC_STORE_BYPASS: Speculative Store Bypass + + Invocations: + * prctl(PR_GET_SPECULATION_CTRL, PR_SPEC_STORE_BYPASS, 0, 0, 0); + * prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_STORE_BYPASS, PR_SPEC_ENABLE, 0, 0); + * prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_STORE_BYPASS, PR_SPEC_DISABLE, 0, 0); + * prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_STORE_BYPASS, PR_SPEC_FORCE_DISABLE, 0, 0); diff --git a/Documentation/vfio.txt b/Documentation/vfio.txt index ef6a5111eaa1..f1a4d3c3ba0b 100644 --- a/Documentation/vfio.txt +++ b/Documentation/vfio.txt @@ -252,15 +252,14 @@ into VFIO core. When devices are bound and unbound to the driver, the driver should call vfio_add_group_dev() and vfio_del_group_dev() respectively:: - extern int vfio_add_group_dev(struct iommu_group *iommu_group, - struct device *dev, + extern int vfio_add_group_dev(struct device *dev, const struct vfio_device_ops *ops, void *device_data); extern void *vfio_del_group_dev(struct device *dev); vfio_add_group_dev() indicates to the core to begin tracking the -specified iommu_group and register the specified dev as owned by +iommu_group of the specified dev and register the dev as owned by a VFIO bus driver. The driver provides an ops structure for callbacks similar to a file operations structure:: diff --git a/Documentation/virtual/kvm/00-INDEX b/Documentation/virtual/kvm/00-INDEX index 3da73aabff5a..3492458a4ae8 100644 --- a/Documentation/virtual/kvm/00-INDEX +++ b/Documentation/virtual/kvm/00-INDEX @@ -1,7 +1,12 @@ 00-INDEX - this file. +amd-memory-encryption.rst + - notes on AMD Secure Encrypted Virtualization feature and SEV firmware + command description api.txt - KVM userspace API. +arm + - internal ABI between the kernel and HYP (for arm/arm64) cpuid.txt - KVM-specific cpuid leaves (x86). devices/ @@ -26,6 +31,5 @@ s390-diag.txt - Diagnose hypercall description (for IBM S/390) timekeeping.txt - timekeeping virtualization for x86-based architectures. -amd-memory-encryption.txt - - notes on AMD Secure Encrypted Virtualization feature and SEV firmware - command description +vcpu-requests.rst + - internal VCPU request API diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index d6b3ff51a14f..758bf403a169 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -1960,6 +1960,9 @@ ARM 32-bit VFP control registers have the following id bit patterns: ARM 64-bit FP registers have the following id bit patterns: 0x4030 0000 0012 0 <regno:12> +ARM firmware pseudo-registers have the following bit pattern: + 0x4030 0000 0014 <regno:16> + arm64 registers are mapped using the lower 32 bits. The upper 16 of that is the register group type, or coprocessor number: @@ -1976,6 +1979,9 @@ arm64 CCSIDR registers are demultiplexed by CSSELR value: arm64 system registers have the following id bit patterns: 0x6030 0000 0013 <op0:2> <op1:3> <crn:4> <crm:4> <op2:3> +arm64 firmware pseudo-registers have the following bit pattern: + 0x6030 0000 0014 <regno:16> + MIPS registers are mapped using the lower 32 bits. The upper 16 of that is the register group type: @@ -2510,7 +2516,8 @@ Possible features: and execute guest code when KVM_RUN is called. - KVM_ARM_VCPU_EL1_32BIT: Starts the CPU in a 32bit mode. Depends on KVM_CAP_ARM_EL1_32BIT (arm64 only). - - KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI v0.2 for the CPU. + - KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI v0.2 (or a future revision + backward compatible with v0.2) for the CPU. Depends on KVM_CAP_ARM_PSCI_0_2. - KVM_ARM_VCPU_PMU_V3: Emulate PMUv3 for the CPU. Depends on KVM_CAP_ARM_PMU_V3. @@ -3480,7 +3487,7 @@ encrypted VMs. Currently, this ioctl is used for issuing Secure Encrypted Virtualization (SEV) commands on AMD Processors. The SEV commands are defined in -Documentation/virtual/kvm/amd-memory-encryption.txt. +Documentation/virtual/kvm/amd-memory-encryption.rst. 4.111 KVM_MEMORY_ENCRYPT_REG_REGION @@ -3516,6 +3523,38 @@ Returns: 0 on success; -1 on error This ioctl can be used to unregister the guest memory region registered with KVM_MEMORY_ENCRYPT_REG_REGION ioctl above. +4.113 KVM_HYPERV_EVENTFD + +Capability: KVM_CAP_HYPERV_EVENTFD +Architectures: x86 +Type: vm ioctl +Parameters: struct kvm_hyperv_eventfd (in) + +This ioctl (un)registers an eventfd to receive notifications from the guest on +the specified Hyper-V connection id through the SIGNAL_EVENT hypercall, without +causing a user exit. SIGNAL_EVENT hypercall with non-zero event flag number +(bits 24-31) still triggers a KVM_EXIT_HYPERV_HCALL user exit. + +struct kvm_hyperv_eventfd { + __u32 conn_id; + __s32 fd; + __u32 flags; + __u32 padding[3]; +}; + +The conn_id field should fit within 24 bits: + +#define KVM_HYPERV_CONN_ID_MASK 0x00ffffff + +The acceptable values for the flags field are: + +#define KVM_HYPERV_EVENTFD_DEASSIGN (1 << 0) + +Returns: 0 on success, + -EINVAL if conn_id or flags is outside the allowed range + -ENOENT on deassign if the conn_id isn't registered + -EEXIST on assign if the conn_id is already registered + 5. The kvm_run structure ------------------------ @@ -3873,7 +3912,7 @@ in userspace. __u64 kvm_dirty_regs; union { struct kvm_sync_regs regs; - char padding[1024]; + char padding[SYNC_REGS_SIZE_BYTES]; } s; If KVM_CAP_SYNC_REGS is defined, these fields allow userspace to access @@ -4078,6 +4117,46 @@ Once this is done the KVM_REG_MIPS_VEC_* and KVM_REG_MIPS_MSA_* registers can be accessed, and the Config5.MSAEn bit is accessible via the KVM API and also from the guest. +6.74 KVM_CAP_SYNC_REGS +Architectures: s390, x86 +Target: s390: always enabled, x86: vcpu +Parameters: none +Returns: x86: KVM_CHECK_EXTENSION returns a bit-array indicating which register +sets are supported (bitfields defined in arch/x86/include/uapi/asm/kvm.h). + +As described above in the kvm_sync_regs struct info in section 5 (kvm_run): +KVM_CAP_SYNC_REGS "allow[s] userspace to access certain guest registers +without having to call SET/GET_*REGS". This reduces overhead by eliminating +repeated ioctl calls for setting and/or getting register values. This is +particularly important when userspace is making synchronous guest state +modifications, e.g. when emulating and/or intercepting instructions in +userspace. + +For s390 specifics, please refer to the source code. + +For x86: +- the register sets to be copied out to kvm_run are selectable + by userspace (rather that all sets being copied out for every exit). +- vcpu_events are available in addition to regs and sregs. + +For x86, the 'kvm_valid_regs' field of struct kvm_run is overloaded to +function as an input bit-array field set by userspace to indicate the +specific register sets to be copied out on the next exit. + +To indicate when userspace has modified values that should be copied into +the vCPU, the all architecture bitarray field, 'kvm_dirty_regs' must be set. +This is done using the same bitflags as for the 'kvm_valid_regs' field. +If the dirty bit is not set, then the register set values will not be copied +into the vCPU even if they've been modified. + +Unused bitfields in the bitarrays must be set to zero. + +struct kvm_sync_regs { + struct kvm_regs regs; + struct kvm_sregs sregs; + struct kvm_vcpu_events events; +}; + 7. Capabilities that can be enabled on VMs ------------------------------------------ @@ -4286,6 +4365,26 @@ enables QEMU to build error log and branch to guest kernel registered machine check handling routine. Without this capability KVM will branch to guests' 0x200 interrupt vector. +7.13 KVM_CAP_X86_DISABLE_EXITS + +Architectures: x86 +Parameters: args[0] defines which exits are disabled +Returns: 0 on success, -EINVAL when args[0] contains invalid exits + +Valid bits in args[0] are + +#define KVM_X86_DISABLE_EXITS_MWAIT (1 << 0) +#define KVM_X86_DISABLE_EXITS_HLT (1 << 1) + +Enabling this capability on a VM provides userspace with a way to no +longer intercept some instructions for improved latency in some +workloads, and is suggested when vCPUs are associated to dedicated +physical CPUs. More bits can be added in the future; userspace can +just pass the KVM_CHECK_EXTENSION result to KVM_ENABLE_CAP to disable +all such vmexits. + +Do not enable KVM_FEATURE_PV_UNHALT if you disable HLT exits. + 8. Other capabilities. ---------------------- @@ -4398,15 +4497,6 @@ reserved. Both registers and addresses are 64-bits wide. It will be possible to run 64-bit or 32-bit guest code. -8.8 KVM_CAP_X86_GUEST_MWAIT - -Architectures: x86 - -This capability indicates that guest using memory monotoring instructions -(MWAIT/MWAITX) to stop the virtual CPU will not cause a VM exit. As such time -spent while virtual CPU is halted in this way will then be accounted for as -guest running time on the host (as opposed to e.g. HLT). - 8.9 KVM_CAP_ARM_USER_IRQ Architectures: arm, arm64 @@ -4483,3 +4573,33 @@ Parameters: none This capability indicates if the flic device will be able to get/set the AIS states for migration via the KVM_DEV_FLIC_AISM_ALL attribute and allows to discover this without having to create a flic device. + +8.14 KVM_CAP_S390_PSW + +Architectures: s390 + +This capability indicates that the PSW is exposed via the kvm_run structure. + +8.15 KVM_CAP_S390_GMAP + +Architectures: s390 + +This capability indicates that the user space memory used as guest mapping can +be anywhere in the user memory address space, as long as the memory slots are +aligned and sized to a segment (1MB) boundary. + +8.16 KVM_CAP_S390_COW + +Architectures: s390 + +This capability indicates that the user space memory used as guest mapping can +use copy-on-write semantics as well as dirty pages tracking via read-only page +tables. + +8.17 KVM_CAP_S390_BPB + +Architectures: s390 + +This capability indicates that kvm will implement the interfaces to handle +reset, migration and nested KVM for branch prediction blocking. The stfle +facility 82 should not be provided to the guest without this capability. diff --git a/Documentation/virtual/kvm/arm/psci.txt b/Documentation/virtual/kvm/arm/psci.txt new file mode 100644 index 000000000000..aafdab887b04 --- /dev/null +++ b/Documentation/virtual/kvm/arm/psci.txt @@ -0,0 +1,30 @@ +KVM implements the PSCI (Power State Coordination Interface) +specification in order to provide services such as CPU on/off, reset +and power-off to the guest. + +The PSCI specification is regularly updated to provide new features, +and KVM implements these updates if they make sense from a virtualization +point of view. + +This means that a guest booted on two different versions of KVM can +observe two different "firmware" revisions. This could cause issues if +a given guest is tied to a particular PSCI revision (unlikely), or if +a migration causes a different PSCI version to be exposed out of the +blue to an unsuspecting guest. + +In order to remedy this situation, KVM exposes a set of "firmware +pseudo-registers" that can be manipulated using the GET/SET_ONE_REG +interface. These registers can be saved/restored by userspace, and set +to a convenient value if required. + +The following register is defined: + +* KVM_REG_ARM_PSCI_VERSION: + + - Only valid if the vcpu has the KVM_ARM_VCPU_PSCI_0_2 feature set + (and thus has already been initialized) + - Returns the current PSCI version on GET_ONE_REG (defaulting to the + highest PSCI version implemented by KVM and compatible with v0.2) + - Allows any PSCI version implemented by KVM and compatible with + v0.2 to be set with SET_ONE_REG + - Affects the whole VM (even if the register view is per-vcpu) diff --git a/Documentation/virtual/kvm/cpuid.txt b/Documentation/virtual/kvm/cpuid.txt index 87a7506f31c2..ab022dcd0911 100644 --- a/Documentation/virtual/kvm/cpuid.txt +++ b/Documentation/virtual/kvm/cpuid.txt @@ -23,8 +23,8 @@ This function queries the presence of KVM cpuid leafs. function: define KVM_CPUID_FEATURES (0x40000001) -returns : ebx, ecx, edx = 0 - eax = and OR'ed group of (1 << flag), where each flags is: +returns : ebx, ecx + eax = an OR'ed group of (1 << flag), where each flags is: flag || value || meaning @@ -66,3 +66,14 @@ KVM_FEATURE_CLOCKSOURCE_STABLE_BIT || 24 || host will warn if no guest-side || || per-cpu warps are expected in || || kvmclock. ------------------------------------------------------------------------------ + + edx = an OR'ed group of (1 << flag), where each flags is: + + +flag || value || meaning +================================================================================== +KVM_HINTS_REALTIME || 0 || guest checks this feature bit to + || || determine that vCPUs are never + || || preempted for an unlimited time, + || || allowing optimizations +---------------------------------------------------------------------------------- diff --git a/Documentation/vm/00-INDEX b/Documentation/vm/00-INDEX index 0278f2c85efb..f4a4f3e884cf 100644 --- a/Documentation/vm/00-INDEX +++ b/Documentation/vm/00-INDEX @@ -1,62 +1,50 @@ 00-INDEX - this file. -active_mm.txt +active_mm.rst - An explanation from Linus about tsk->active_mm vs tsk->mm. -balance +balance.rst - various information on memory balancing. -cleancache.txt +cleancache.rst - Intro to cleancache and page-granularity victim cache. -frontswap.txt +frontswap.rst - Outline frontswap, part of the transcendent memory frontend. -highmem.txt +highmem.rst - Outline of highmem and common issues. -hmm.txt +hmm.rst - Documentation of heterogeneous memory management -hugetlbpage.txt - - a brief summary of hugetlbpage support in the Linux kernel. -hugetlbfs_reserv.txt +hugetlbfs_reserv.rst - A brief overview of hugetlbfs reservation design/implementation. -hwpoison.txt +hwpoison.rst - explains what hwpoison is -idle_page_tracking.txt - - description of the idle page tracking feature. -ksm.txt +ksm.rst - how to use the Kernel Samepage Merging feature. -mmu_notifier.txt +mmu_notifier.rst - a note about clearing pte/pmd and mmu notifications -numa +numa.rst - information about NUMA specific code in the Linux vm. -numa_memory_policy.txt - - documentation of concepts and APIs of the 2.6 memory policy support. -overcommit-accounting +overcommit-accounting.rst - description of the Linux kernels overcommit handling modes. -page_frags +page_frags.rst - description of page fragments allocator -page_migration +page_migration.rst - description of page migration in NUMA systems. -pagemap.txt - - pagemap, from the userspace perspective -page_owner.txt +page_owner.rst - tracking about who allocated each page -remap_file_pages.txt +remap_file_pages.rst - a note about remap_file_pages() system call -slub.txt +slub.rst - a short users guide for SLUB. -soft-dirty.txt - - short explanation for soft-dirty PTEs -split_page_table_lock +split_page_table_lock.rst - Separate per-table lock to improve scalability of the old page_table_lock. -swap_numa.txt +swap_numa.rst - automatic binding of swap device to numa node -transhuge.txt +transhuge.rst - Transparent Hugepage Support, alternative way of using hugepages. -unevictable-lru.txt +unevictable-lru.rst - Unevictable LRU infrastructure -userfaultfd.txt - - description of userfaultfd system call z3fold.txt - outline of z3fold allocator for storing compressed pages -zsmalloc.txt +zsmalloc.rst - outline of zsmalloc allocator for storing compressed pages -zswap.txt +zswap.rst - Intro to compressed cache for swap pages diff --git a/Documentation/vm/active_mm.rst b/Documentation/vm/active_mm.rst new file mode 100644 index 000000000000..c84471b180f8 --- /dev/null +++ b/Documentation/vm/active_mm.rst @@ -0,0 +1,91 @@ +.. _active_mm: + +========= +Active MM +========= + +:: + + List: linux-kernel + Subject: Re: active_mm + From: Linus Torvalds <torvalds () transmeta ! com> + Date: 1999-07-30 21:36:24 + + Cc'd to linux-kernel, because I don't write explanations all that often, + and when I do I feel better about more people reading them. + + On Fri, 30 Jul 1999, David Mosberger wrote: + > + > Is there a brief description someplace on how "mm" vs. "active_mm" in + > the task_struct are supposed to be used? (My apologies if this was + > discussed on the mailing lists---I just returned from vacation and + > wasn't able to follow linux-kernel for a while). + + Basically, the new setup is: + + - we have "real address spaces" and "anonymous address spaces". The + difference is that an anonymous address space doesn't care about the + user-level page tables at all, so when we do a context switch into an + anonymous address space we just leave the previous address space + active. + + The obvious use for a "anonymous address space" is any thread that + doesn't need any user mappings - all kernel threads basically fall into + this category, but even "real" threads can temporarily say that for + some amount of time they are not going to be interested in user space, + and that the scheduler might as well try to avoid wasting time on + switching the VM state around. Currently only the old-style bdflush + sync does that. + + - "tsk->mm" points to the "real address space". For an anonymous process, + tsk->mm will be NULL, for the logical reason that an anonymous process + really doesn't _have_ a real address space at all. + + - however, we obviously need to keep track of which address space we + "stole" for such an anonymous user. For that, we have "tsk->active_mm", + which shows what the currently active address space is. + + The rule is that for a process with a real address space (ie tsk->mm is + non-NULL) the active_mm obviously always has to be the same as the real + one. + + For a anonymous process, tsk->mm == NULL, and tsk->active_mm is the + "borrowed" mm while the anonymous process is running. When the + anonymous process gets scheduled away, the borrowed address space is + returned and cleared. + + To support all that, the "struct mm_struct" now has two counters: a + "mm_users" counter that is how many "real address space users" there are, + and a "mm_count" counter that is the number of "lazy" users (ie anonymous + users) plus one if there are any real users. + + Usually there is at least one real user, but it could be that the real + user exited on another CPU while a lazy user was still active, so you do + actually get cases where you have a address space that is _only_ used by + lazy users. That is often a short-lived state, because once that thread + gets scheduled away in favour of a real thread, the "zombie" mm gets + released because "mm_users" becomes zero. + + Also, a new rule is that _nobody_ ever has "init_mm" as a real MM any + more. "init_mm" should be considered just a "lazy context when no other + context is available", and in fact it is mainly used just at bootup when + no real VM has yet been created. So code that used to check + + if (current->mm == &init_mm) + + should generally just do + + if (!current->mm) + + instead (which makes more sense anyway - the test is basically one of "do + we have a user context", and is generally done by the page fault handler + and things like that). + + Anyway, I put a pre-patch-2.3.13-1 on ftp.kernel.org just a moment ago, + because it slightly changes the interfaces to accommodate the alpha (who + would have thought it, but the alpha actually ends up having one of the + ugliest context switch codes - unlike the other architectures where the MM + and register state is separate, the alpha PALcode joins the two, and you + need to switch both together). + + (From http://marc.info/?l=linux-kernel&m=93337278602211&w=2) diff --git a/Documentation/vm/active_mm.txt b/Documentation/vm/active_mm.txt deleted file mode 100644 index dbf45817405f..000000000000 --- a/Documentation/vm/active_mm.txt +++ /dev/null @@ -1,83 +0,0 @@ -List: linux-kernel -Subject: Re: active_mm -From: Linus Torvalds <torvalds () transmeta ! com> -Date: 1999-07-30 21:36:24 - -Cc'd to linux-kernel, because I don't write explanations all that often, -and when I do I feel better about more people reading them. - -On Fri, 30 Jul 1999, David Mosberger wrote: -> -> Is there a brief description someplace on how "mm" vs. "active_mm" in -> the task_struct are supposed to be used? (My apologies if this was -> discussed on the mailing lists---I just returned from vacation and -> wasn't able to follow linux-kernel for a while). - -Basically, the new setup is: - - - we have "real address spaces" and "anonymous address spaces". The - difference is that an anonymous address space doesn't care about the - user-level page tables at all, so when we do a context switch into an - anonymous address space we just leave the previous address space - active. - - The obvious use for a "anonymous address space" is any thread that - doesn't need any user mappings - all kernel threads basically fall into - this category, but even "real" threads can temporarily say that for - some amount of time they are not going to be interested in user space, - and that the scheduler might as well try to avoid wasting time on - switching the VM state around. Currently only the old-style bdflush - sync does that. - - - "tsk->mm" points to the "real address space". For an anonymous process, - tsk->mm will be NULL, for the logical reason that an anonymous process - really doesn't _have_ a real address space at all. - - - however, we obviously need to keep track of which address space we - "stole" for such an anonymous user. For that, we have "tsk->active_mm", - which shows what the currently active address space is. - - The rule is that for a process with a real address space (ie tsk->mm is - non-NULL) the active_mm obviously always has to be the same as the real - one. - - For a anonymous process, tsk->mm == NULL, and tsk->active_mm is the - "borrowed" mm while the anonymous process is running. When the - anonymous process gets scheduled away, the borrowed address space is - returned and cleared. - -To support all that, the "struct mm_struct" now has two counters: a -"mm_users" counter that is how many "real address space users" there are, -and a "mm_count" counter that is the number of "lazy" users (ie anonymous -users) plus one if there are any real users. - -Usually there is at least one real user, but it could be that the real -user exited on another CPU while a lazy user was still active, so you do -actually get cases where you have a address space that is _only_ used by -lazy users. That is often a short-lived state, because once that thread -gets scheduled away in favour of a real thread, the "zombie" mm gets -released because "mm_users" becomes zero. - -Also, a new rule is that _nobody_ ever has "init_mm" as a real MM any -more. "init_mm" should be considered just a "lazy context when no other -context is available", and in fact it is mainly used just at bootup when -no real VM has yet been created. So code that used to check - - if (current->mm == &init_mm) - -should generally just do - - if (!current->mm) - -instead (which makes more sense anyway - the test is basically one of "do -we have a user context", and is generally done by the page fault handler -and things like that). - -Anyway, I put a pre-patch-2.3.13-1 on ftp.kernel.org just a moment ago, -because it slightly changes the interfaces to accommodate the alpha (who -would have thought it, but the alpha actually ends up having one of the -ugliest context switch codes - unlike the other architectures where the MM -and register state is separate, the alpha PALcode joins the two, and you -need to switch both together). - -(From http://marc.info/?l=linux-kernel&m=93337278602211&w=2) diff --git a/Documentation/vm/balance b/Documentation/vm/balance.rst index 964595481af6..6a1fadf3e173 100644 --- a/Documentation/vm/balance +++ b/Documentation/vm/balance.rst @@ -1,3 +1,9 @@ +.. _balance: + +================ +Memory Balancing +================ + Started Jan 2000 by Kanoj Sarcar <kanoj@sgi.com> Memory balancing is needed for !__GFP_ATOMIC and !__GFP_KSWAPD_RECLAIM as @@ -62,11 +68,11 @@ for non-sleepable allocations. Second, the HIGHMEM zone is also balanced, so as to give a fighting chance for replace_with_highmem() to get a HIGHMEM page, as well as to ensure that HIGHMEM allocations do not fall back into regular zone. This also makes sure that HIGHMEM pages -are not leaked (for example, in situations where a HIGHMEM page is in +are not leaked (for example, in situations where a HIGHMEM page is in the swapcache but is not being used by anyone) kswapd also needs to know about the zones it should balance. kswapd is -primarily needed in a situation where balancing can not be done, +primarily needed in a situation where balancing can not be done, probably because all allocation requests are coming from intr context and all process contexts are sleeping. For 2.3, kswapd does not really need to balance the highmem zone, since intr context does not request @@ -89,7 +95,8 @@ pages is below watermark[WMARK_LOW]; in which case zone_wake_kswapd is also set. (Good) Ideas that I have heard: + 1. Dynamic experience should influence balancing: number of failed requests -for a zone can be tracked and fed into the balancing scheme (jalvo@mbay.net) + for a zone can be tracked and fed into the balancing scheme (jalvo@mbay.net) 2. Implement a replace_with_highmem()-like replace_with_regular() to preserve -dma pages. (lkd@tantalophile.demon.co.uk) + dma pages. (lkd@tantalophile.demon.co.uk) diff --git a/Documentation/vm/cleancache.txt b/Documentation/vm/cleancache.rst index e4b49df7a048..68cba9131c31 100644 --- a/Documentation/vm/cleancache.txt +++ b/Documentation/vm/cleancache.rst @@ -1,4 +1,11 @@ -MOTIVATION +.. _cleancache: + +========== +Cleancache +========== + +Motivation +========== Cleancache is a new optional feature provided by the VFS layer that potentially dramatically increases page cache effectiveness for @@ -21,9 +28,10 @@ Transcendent memory "drivers" for cleancache are currently implemented in Xen (using hypervisor memory) and zcache (using in-kernel compressed memory) and other implementations are in development. -FAQs are included below. +:ref:`FAQs <faq>` are included below. -IMPLEMENTATION OVERVIEW +Implementation Overview +======================= A cleancache "backend" that provides transcendent memory registers itself to the kernel's cleancache "frontend" by calling cleancache_register_ops, @@ -80,22 +88,33 @@ different Linux threads are simultaneously putting and invalidating a page with the same handle, the results are indeterminate. Callers must lock the page to ensure serial behavior. -CLEANCACHE PERFORMANCE METRICS +Cleancache Performance Metrics +============================== If properly configured, monitoring of cleancache is done via debugfs in -the /sys/kernel/debug/cleancache directory. The effectiveness of cleancache +the `/sys/kernel/debug/cleancache` directory. The effectiveness of cleancache can be measured (across all filesystems) with: -succ_gets - number of gets that were successful -failed_gets - number of gets that failed -puts - number of puts attempted (all "succeed") -invalidates - number of invalidates attempted +``succ_gets`` + number of gets that were successful + +``failed_gets`` + number of gets that failed + +``puts`` + number of puts attempted (all "succeed") + +``invalidates`` + number of invalidates attempted A backend implementation may provide additional metrics. +.. _faq: + FAQ +=== -1) Where's the value? (Andrew Morton) +* Where's the value? (Andrew Morton) Cleancache provides a significant performance benefit to many workloads in many environments with negligible overhead by improving the @@ -137,8 +156,8 @@ device that stores pages of data in a compressed state. And the proposed "RAMster" driver shares RAM across multiple physical systems. -2) Why does cleancache have its sticky fingers so deep inside the - filesystems and VFS? (Andrew Morton and Christoph Hellwig) +* Why does cleancache have its sticky fingers so deep inside the + filesystems and VFS? (Andrew Morton and Christoph Hellwig) The core hooks for cleancache in VFS are in most cases a single line and the minimum set are placed precisely where needed to maintain @@ -168,9 +187,9 @@ filesystems in the future. The total impact of the hooks to existing fs and mm files is only about 40 lines added (not counting comments and blank lines). -3) Why not make cleancache asynchronous and batched so it can - more easily interface with real devices with DMA instead - of copying each individual page? (Minchan Kim) +* Why not make cleancache asynchronous and batched so it can more + easily interface with real devices with DMA instead of copying each + individual page? (Minchan Kim) The one-page-at-a-time copy semantics simplifies the implementation on both the frontend and backend and also allows the backend to @@ -182,8 +201,8 @@ are avoided. While the interface seems odd for a "real device" or for real kernel-addressable RAM, it makes perfect sense for transcendent memory. -4) Why is non-shared cleancache "exclusive"? And where is the - page "invalidated" after a "get"? (Minchan Kim) +* Why is non-shared cleancache "exclusive"? And where is the + page "invalidated" after a "get"? (Minchan Kim) The main reason is to free up space in transcendent memory and to avoid unnecessary cleancache_invalidate calls. If you want inclusive, @@ -193,7 +212,7 @@ be easily extended to add a "get_no_invalidate" call. The invalidate is done by the cleancache backend implementation. -5) What's the performance impact? +* What's the performance impact? Performance analysis has been presented at OLS'09 and LCA'10. Briefly, performance gains can be significant on most workloads, @@ -206,7 +225,7 @@ single-core systems with slow memory-copy speeds, cleancache has little value, but in newer multicore machines, especially consolidated/virtualized machines, it has great value. -6) How do I add cleancache support for filesystem X? (Boaz Harrash) +* How do I add cleancache support for filesystem X? (Boaz Harrash) Filesystems that are well-behaved and conform to certain restrictions can utilize cleancache simply by making a call to @@ -217,26 +236,26 @@ not enable the optional cleancache. Some points for a filesystem to consider: -- The FS should be block-device-based (e.g. a ram-based FS such - as tmpfs should not enable cleancache) -- To ensure coherency/correctness, the FS must ensure that all - file removal or truncation operations either go through VFS or - add hooks to do the equivalent cleancache "invalidate" operations -- To ensure coherency/correctness, either inode numbers must - be unique across the lifetime of the on-disk file OR the - FS must provide an "encode_fh" function. -- The FS must call the VFS superblock alloc and deactivate routines - or add hooks to do the equivalent cleancache calls done there. -- To maximize performance, all pages fetched from the FS should - go through the do_mpag_readpage routine or the FS should add - hooks to do the equivalent (cf. btrfs) -- Currently, the FS blocksize must be the same as PAGESIZE. This - is not an architectural restriction, but no backends currently - support anything different. -- A clustered FS should invoke the "shared_init_fs" cleancache - hook to get best performance for some backends. - -7) Why not use the KVA of the inode as the key? (Christoph Hellwig) + - The FS should be block-device-based (e.g. a ram-based FS such + as tmpfs should not enable cleancache) + - To ensure coherency/correctness, the FS must ensure that all + file removal or truncation operations either go through VFS or + add hooks to do the equivalent cleancache "invalidate" operations + - To ensure coherency/correctness, either inode numbers must + be unique across the lifetime of the on-disk file OR the + FS must provide an "encode_fh" function. + - The FS must call the VFS superblock alloc and deactivate routines + or add hooks to do the equivalent cleancache calls done there. + - To maximize performance, all pages fetched from the FS should + go through the do_mpag_readpage routine or the FS should add + hooks to do the equivalent (cf. btrfs) + - Currently, the FS blocksize must be the same as PAGESIZE. This + is not an architectural restriction, but no backends currently + support anything different. + - A clustered FS should invoke the "shared_init_fs" cleancache + hook to get best performance for some backends. + +* Why not use the KVA of the inode as the key? (Christoph Hellwig) If cleancache would use the inode virtual address instead of inode/filehandle, the pool id could be eliminated. But, this @@ -251,7 +270,7 @@ of cleancache would be lost because the cache of pages in cleanache is potentially much larger than the kernel pagecache and is most useful if the pages survive inode cache removal. -8) Why is a global variable required? +* Why is a global variable required? The cleancache_enabled flag is checked in all of the frequently-used cleancache hooks. The alternative is a function call to check a static @@ -262,14 +281,14 @@ global variable allows cleancache to be enabled by default at compile time, but have insignificant performance impact when cleancache remains disabled at runtime. -9) Does cleanache work with KVM? +* Does cleanache work with KVM? The memory model of KVM is sufficiently different that a cleancache backend may have less value for KVM. This remains to be tested, especially in an overcommitted system. -10) Does cleancache work in userspace? It sounds useful for - memory hungry caches like web browsers. (Jamie Lokier) +* Does cleancache work in userspace? It sounds useful for + memory hungry caches like web browsers. (Jamie Lokier) No plans yet, though we agree it sounds useful, at least for apps that bypass the page cache (e.g. O_DIRECT). diff --git a/Documentation/vm/conf.py b/Documentation/vm/conf.py new file mode 100644 index 000000000000..3b0b601af558 --- /dev/null +++ b/Documentation/vm/conf.py @@ -0,0 +1,10 @@ +# -*- coding: utf-8; mode: python -*- + +project = "Linux Memory Management Documentation" + +tags.add("subproject") + +latex_documents = [ + ('index', 'memory-management.tex', project, + 'The kernel development community', 'manual'), +] diff --git a/Documentation/vm/frontswap.txt b/Documentation/vm/frontswap.rst index c71a019be600..1979f430c1c5 100644 --- a/Documentation/vm/frontswap.txt +++ b/Documentation/vm/frontswap.rst @@ -1,13 +1,20 @@ +.. _frontswap: + +========= +Frontswap +========= + Frontswap provides a "transcendent memory" interface for swap pages. In some environments, dramatic performance savings may be obtained because swapped pages are saved in RAM (or a RAM-like device) instead of a swap disk. -(Note, frontswap -- and cleancache (merged at 3.0) -- are the "frontends" +(Note, frontswap -- and :ref:`cleancache` (merged at 3.0) -- are the "frontends" and the only necessary changes to the core kernel for transcendent memory; all other supporting code -- the "backends" -- is implemented as drivers. -See the LWN.net article "Transcendent memory in a nutshell" for a detailed -overview of frontswap and related kernel parts: -https://lwn.net/Articles/454795/ ) +See the LWN.net article `Transcendent memory in a nutshell`_ +for a detailed overview of frontswap and related kernel parts) + +.. _Transcendent memory in a nutshell: https://lwn.net/Articles/454795/ Frontswap is so named because it can be thought of as the opposite of a "backing" store for a swap device. The storage is assumed to be @@ -50,19 +57,27 @@ or the store fails AND the page is invalidated. This ensures stale data may never be obtained from frontswap. If properly configured, monitoring of frontswap is done via debugfs in -the /sys/kernel/debug/frontswap directory. The effectiveness of +the `/sys/kernel/debug/frontswap` directory. The effectiveness of frontswap can be measured (across all swap devices) with: -failed_stores - how many store attempts have failed -loads - how many loads were attempted (all should succeed) -succ_stores - how many store attempts have succeeded -invalidates - how many invalidates were attempted +``failed_stores`` + how many store attempts have failed + +``loads`` + how many loads were attempted (all should succeed) + +``succ_stores`` + how many store attempts have succeeded + +``invalidates`` + how many invalidates were attempted A backend implementation may provide additional metrics. FAQ +=== -1) Where's the value? +* Where's the value? When a workload starts swapping, performance falls through the floor. Frontswap significantly increases performance in many such workloads by @@ -117,8 +132,8 @@ A KVM implementation is underway and has been RFC'ed to lkml. And, using frontswap, investigation is also underway on the use of NVM as a memory extension technology. -2) Sure there may be performance advantages in some situations, but - what's the space/time overhead of frontswap? +* Sure there may be performance advantages in some situations, but + what's the space/time overhead of frontswap? If CONFIG_FRONTSWAP is disabled, every frontswap hook compiles into nothingness and the only overhead is a few extra bytes per swapon'ed @@ -148,8 +163,8 @@ pressure that can potentially outweigh the other advantages. A backend, such as zcache, must implement policies to carefully (but dynamically) manage memory limits to ensure this doesn't happen. -3) OK, how about a quick overview of what this frontswap patch does - in terms that a kernel hacker can grok? +* OK, how about a quick overview of what this frontswap patch does + in terms that a kernel hacker can grok? Let's assume that a frontswap "backend" has registered during kernel initialization; this registration indicates that this @@ -188,9 +203,9 @@ and (potentially) a swap device write are replaced by a "frontswap backend store" and (possibly) a "frontswap backend loads", which are presumably much faster. -4) Can't frontswap be configured as a "special" swap device that is - just higher priority than any real swap device (e.g. like zswap, - or maybe swap-over-nbd/NFS)? +* Can't frontswap be configured as a "special" swap device that is + just higher priority than any real swap device (e.g. like zswap, + or maybe swap-over-nbd/NFS)? No. First, the existing swap subsystem doesn't allow for any kind of swap hierarchy. Perhaps it could be rewritten to accommodate a hierarchy, @@ -240,9 +255,9 @@ installation, frontswap is useless. Swapless portable devices can still use frontswap but a backend for such devices must configure some kind of "ghost" swap device and ensure that it is never used. -5) Why this weird definition about "duplicate stores"? If a page - has been previously successfully stored, can't it always be - successfully overwritten? +* Why this weird definition about "duplicate stores"? If a page + has been previously successfully stored, can't it always be + successfully overwritten? Nearly always it can, but no, sometimes it cannot. Consider an example where data is compressed and the original 4K page has been compressed @@ -254,7 +269,7 @@ the old data and ensure that it is no longer accessible. Since the swap subsystem then writes the new data to the read swap device, this is the correct course of action to ensure coherency. -6) What is frontswap_shrink for? +* What is frontswap_shrink for? When the (non-frontswap) swap subsystem swaps out a page to a real swap device, that page is only taking up low-value pre-allocated disk @@ -267,7 +282,7 @@ to "repatriate" pages sent to a remote machine back to the local machine; this is driven using the frontswap_shrink mechanism when memory pressure subsides. -7) Why does the frontswap patch create the new include file swapfile.h? +* Why does the frontswap patch create the new include file swapfile.h? The frontswap code depends on some swap-subsystem-internal data structures that have, over the years, moved back and forth between diff --git a/Documentation/vm/highmem.txt b/Documentation/vm/highmem.rst index 4324d24ffacd..0f69a9fec34d 100644 --- a/Documentation/vm/highmem.txt +++ b/Documentation/vm/highmem.rst @@ -1,25 +1,14 @@ +.. _highmem: - ==================== - HIGH MEMORY HANDLING - ==================== +==================== +High Memory Handling +==================== By: Peter Zijlstra <a.p.zijlstra@chello.nl> -Contents: - - (*) What is high memory? - - (*) Temporary virtual mappings. - - (*) Using kmap_atomic. - - (*) Cost of temporary mappings. - - (*) i386 PAE. +.. contents:: :local: - -==================== -WHAT IS HIGH MEMORY? +What Is High Memory? ==================== High memory (highmem) is used when the size of physical memory approaches or @@ -38,7 +27,7 @@ kernel entry/exit. This means the available virtual memory space (4GiB on i386) has to be divided between user and kernel space. The traditional split for architectures using this approach is 3:1, 3GiB for -userspace and the top 1GiB for kernel space: +userspace and the top 1GiB for kernel space:: +--------+ 0xffffffff | Kernel | @@ -58,40 +47,38 @@ and user maps. Some hardware (like some ARMs), however, have limited virtual space when they use mm context tags. -========================== -TEMPORARY VIRTUAL MAPPINGS +Temporary Virtual Mappings ========================== The kernel contains several ways of creating temporary mappings: - (*) vmap(). This can be used to make a long duration mapping of multiple - physical pages into a contiguous virtual space. It needs global - synchronization to unmap. +* vmap(). This can be used to make a long duration mapping of multiple + physical pages into a contiguous virtual space. It needs global + synchronization to unmap. - (*) kmap(). This permits a short duration mapping of a single page. It needs - global synchronization, but is amortized somewhat. It is also prone to - deadlocks when using in a nested fashion, and so it is not recommended for - new code. +* kmap(). This permits a short duration mapping of a single page. It needs + global synchronization, but is amortized somewhat. It is also prone to + deadlocks when using in a nested fashion, and so it is not recommended for + new code. - (*) kmap_atomic(). This permits a very short duration mapping of a single - page. Since the mapping is restricted to the CPU that issued it, it - performs well, but the issuing task is therefore required to stay on that - CPU until it has finished, lest some other task displace its mappings. +* kmap_atomic(). This permits a very short duration mapping of a single + page. Since the mapping is restricted to the CPU that issued it, it + performs well, but the issuing task is therefore required to stay on that + CPU until it has finished, lest some other task displace its mappings. - kmap_atomic() may also be used by interrupt contexts, since it is does not - sleep and the caller may not sleep until after kunmap_atomic() is called. + kmap_atomic() may also be used by interrupt contexts, since it is does not + sleep and the caller may not sleep until after kunmap_atomic() is called. - It may be assumed that k[un]map_atomic() won't fail. + It may be assumed that k[un]map_atomic() won't fail. -================= -USING KMAP_ATOMIC +Using kmap_atomic ================= When and where to use kmap_atomic() is straightforward. It is used when code wants to access the contents of a page that might be allocated from high memory (see __GFP_HIGHMEM), for example a page in the pagecache. The API has two -functions, and they can be used in a manner similar to the following: +functions, and they can be used in a manner similar to the following:: /* Find the page of interest. */ struct page *page = find_get_page(mapping, offset); @@ -109,7 +96,7 @@ Note that the kunmap_atomic() call takes the result of the kmap_atomic() call not the argument. If you need to map two pages because you want to copy from one page to -another you need to keep the kmap_atomic calls strictly nested, like: +another you need to keep the kmap_atomic calls strictly nested, like:: vaddr1 = kmap_atomic(page1); vaddr2 = kmap_atomic(page2); @@ -120,8 +107,7 @@ another you need to keep the kmap_atomic calls strictly nested, like: kunmap_atomic(vaddr1); -========================== -COST OF TEMPORARY MAPPINGS +Cost of Temporary Mappings ========================== The cost of creating temporary mappings can be quite high. The arch has to @@ -136,25 +122,24 @@ If CONFIG_MMU is not set, then there can be no temporary mappings and no highmem. In such a case, the arithmetic approach will also be used. -======== i386 PAE ======== The i386 arch, under some circumstances, will permit you to stick up to 64GiB of RAM into your 32-bit machine. This has a number of consequences: - (*) Linux needs a page-frame structure for each page in the system and the - pageframes need to live in the permanent mapping, which means: +* Linux needs a page-frame structure for each page in the system and the + pageframes need to live in the permanent mapping, which means: - (*) you can have 896M/sizeof(struct page) page-frames at most; with struct - page being 32-bytes that would end up being something in the order of 112G - worth of pages; the kernel, however, needs to store more than just - page-frames in that memory... +* you can have 896M/sizeof(struct page) page-frames at most; with struct + page being 32-bytes that would end up being something in the order of 112G + worth of pages; the kernel, however, needs to store more than just + page-frames in that memory... - (*) PAE makes your page tables larger - which slows the system down as more - data has to be accessed to traverse in TLB fills and the like. One - advantage is that PAE has more PTE bits and can provide advanced features - like NX and PAT. +* PAE makes your page tables larger - which slows the system down as more + data has to be accessed to traverse in TLB fills and the like. One + advantage is that PAE has more PTE bits and can provide advanced features + like NX and PAT. The general recommendation is that you don't use more than 8GiB on a 32-bit machine - although more might work for you and your workload, you're pretty diff --git a/Documentation/vm/hmm.rst b/Documentation/vm/hmm.rst new file mode 100644 index 000000000000..cdf3911582c8 --- /dev/null +++ b/Documentation/vm/hmm.rst @@ -0,0 +1,386 @@ +.. hmm: + +===================================== +Heterogeneous Memory Management (HMM) +===================================== + +Provide infrastructure and helpers to integrate non-conventional memory (device +memory like GPU on board memory) into regular kernel path, with the cornerstone +of this being specialized struct page for such memory (see sections 5 to 7 of +this document). + +HMM also provides optional helpers for SVM (Share Virtual Memory), i.e., +allowing a device to transparently access program address coherently with +the CPU meaning that any valid pointer on the CPU is also a valid pointer +for the device. This is becoming mandatory to simplify the use of advanced +heterogeneous computing where GPU, DSP, or FPGA are used to perform various +computations on behalf of a process. + +This document is divided as follows: in the first section I expose the problems +related to using device specific memory allocators. In the second section, I +expose the hardware limitations that are inherent to many platforms. The third +section gives an overview of the HMM design. The fourth section explains how +CPU page-table mirroring works and the purpose of HMM in this context. The +fifth section deals with how device memory is represented inside the kernel. +Finally, the last section presents a new migration helper that allows lever- +aging the device DMA engine. + +.. contents:: :local: + +Problems of using a device specific memory allocator +==================================================== + +Devices with a large amount of on board memory (several gigabytes) like GPUs +have historically managed their memory through dedicated driver specific APIs. +This creates a disconnect between memory allocated and managed by a device +driver and regular application memory (private anonymous, shared memory, or +regular file backed memory). From here on I will refer to this aspect as split +address space. I use shared address space to refer to the opposite situation: +i.e., one in which any application memory region can be used by a device +transparently. + +Split address space happens because device can only access memory allocated +through device specific API. This implies that all memory objects in a program +are not equal from the device point of view which complicates large programs +that rely on a wide set of libraries. + +Concretely this means that code that wants to leverage devices like GPUs needs +to copy object between generically allocated memory (malloc, mmap private, mmap +share) and memory allocated through the device driver API (this still ends up +with an mmap but of the device file). + +For flat data sets (array, grid, image, ...) this isn't too hard to achieve but +complex data sets (list, tree, ...) are hard to get right. Duplicating a +complex data set needs to re-map all the pointer relations between each of its +elements. This is error prone and program gets harder to debug because of the +duplicate data set and addresses. + +Split address space also means that libraries cannot transparently use data +they are getting from the core program or another library and thus each library +might have to duplicate its input data set using the device specific memory +allocator. Large projects suffer from this and waste resources because of the +various memory copies. + +Duplicating each library API to accept as input or output memory allocated by +each device specific allocator is not a viable option. It would lead to a +combinatorial explosion in the library entry points. + +Finally, with the advance of high level language constructs (in C++ but in +other languages too) it is now possible for the compiler to leverage GPUs and +other devices without programmer knowledge. Some compiler identified patterns +are only do-able with a shared address space. It is also more reasonable to use +a shared address space for all other patterns. + + +I/O bus, device memory characteristics +====================================== + +I/O buses cripple shared address spaces due to a few limitations. Most I/O +buses only allow basic memory access from device to main memory; even cache +coherency is often optional. Access to device memory from CPU is even more +limited. More often than not, it is not cache coherent. + +If we only consider the PCIE bus, then a device can access main memory (often +through an IOMMU) and be cache coherent with the CPUs. However, it only allows +a limited set of atomic operations from device on main memory. This is worse +in the other direction: the CPU can only access a limited range of the device +memory and cannot perform atomic operations on it. Thus device memory cannot +be considered the same as regular memory from the kernel point of view. + +Another crippling factor is the limited bandwidth (~32GBytes/s with PCIE 4.0 +and 16 lanes). This is 33 times less than the fastest GPU memory (1 TBytes/s). +The final limitation is latency. Access to main memory from the device has an +order of magnitude higher latency than when the device accesses its own memory. + +Some platforms are developing new I/O buses or additions/modifications to PCIE +to address some of these limitations (OpenCAPI, CCIX). They mainly allow two- +way cache coherency between CPU and device and allow all atomic operations the +architecture supports. Sadly, not all platforms are following this trend and +some major architectures are left without hardware solutions to these problems. + +So for shared address space to make sense, not only must we allow devices to +access any memory but we must also permit any memory to be migrated to device +memory while device is using it (blocking CPU access while it happens). + + +Shared address space and migration +================================== + +HMM intends to provide two main features. First one is to share the address +space by duplicating the CPU page table in the device page table so the same +address points to the same physical memory for any valid main memory address in +the process address space. + +To achieve this, HMM offers a set of helpers to populate the device page table +while keeping track of CPU page table updates. Device page table updates are +not as easy as CPU page table updates. To update the device page table, you must +allocate a buffer (or use a pool of pre-allocated buffers) and write GPU +specific commands in it to perform the update (unmap, cache invalidations, and +flush, ...). This cannot be done through common code for all devices. Hence +why HMM provides helpers to factor out everything that can be while leaving the +hardware specific details to the device driver. + +The second mechanism HMM provides is a new kind of ZONE_DEVICE memory that +allows allocating a struct page for each page of the device memory. Those pages +are special because the CPU cannot map them. However, they allow migrating +main memory to device memory using existing migration mechanisms and everything +looks like a page is swapped out to disk from the CPU point of view. Using a +struct page gives the easiest and cleanest integration with existing mm mech- +anisms. Here again, HMM only provides helpers, first to hotplug new ZONE_DEVICE +memory for the device memory and second to perform migration. Policy decisions +of what and when to migrate things is left to the device driver. + +Note that any CPU access to a device page triggers a page fault and a migration +back to main memory. For example, when a page backing a given CPU address A is +migrated from a main memory page to a device page, then any CPU access to +address A triggers a page fault and initiates a migration back to main memory. + +With these two features, HMM not only allows a device to mirror process address +space and keeping both CPU and device page table synchronized, but also lever- +ages device memory by migrating the part of the data set that is actively being +used by the device. + + +Address space mirroring implementation and API +============================================== + +Address space mirroring's main objective is to allow duplication of a range of +CPU page table into a device page table; HMM helps keep both synchronized. A +device driver that wants to mirror a process address space must start with the +registration of an hmm_mirror struct:: + + int hmm_mirror_register(struct hmm_mirror *mirror, + struct mm_struct *mm); + int hmm_mirror_register_locked(struct hmm_mirror *mirror, + struct mm_struct *mm); + + +The locked variant is to be used when the driver is already holding mmap_sem +of the mm in write mode. The mirror struct has a set of callbacks that are used +to propagate CPU page tables:: + + struct hmm_mirror_ops { + /* sync_cpu_device_pagetables() - synchronize page tables + * + * @mirror: pointer to struct hmm_mirror + * @update_type: type of update that occurred to the CPU page table + * @start: virtual start address of the range to update + * @end: virtual end address of the range to update + * + * This callback ultimately originates from mmu_notifiers when the CPU + * page table is updated. The device driver must update its page table + * in response to this callback. The update argument tells what action + * to perform. + * + * The device driver must not return from this callback until the device + * page tables are completely updated (TLBs flushed, etc); this is a + * synchronous call. + */ + void (*update)(struct hmm_mirror *mirror, + enum hmm_update action, + unsigned long start, + unsigned long end); + }; + +The device driver must perform the update action to the range (mark range +read only, or fully unmap, ...). The device must be done with the update before +the driver callback returns. + +When the device driver wants to populate a range of virtual addresses, it can +use either:: + + int hmm_vma_get_pfns(struct vm_area_struct *vma, + struct hmm_range *range, + unsigned long start, + unsigned long end, + hmm_pfn_t *pfns); + int hmm_vma_fault(struct vm_area_struct *vma, + struct hmm_range *range, + unsigned long start, + unsigned long end, + hmm_pfn_t *pfns, + bool write, + bool block); + +The first one (hmm_vma_get_pfns()) will only fetch present CPU page table +entries and will not trigger a page fault on missing or non-present entries. +The second one does trigger a page fault on missing or read-only entry if the +write parameter is true. Page faults use the generic mm page fault code path +just like a CPU page fault. + +Both functions copy CPU page table entries into their pfns array argument. Each +entry in that array corresponds to an address in the virtual range. HMM +provides a set of flags to help the driver identify special CPU page table +entries. + +Locking with the update() callback is the most important aspect the driver must +respect in order to keep things properly synchronized. The usage pattern is:: + + int driver_populate_range(...) + { + struct hmm_range range; + ... + again: + ret = hmm_vma_get_pfns(vma, &range, start, end, pfns); + if (ret) + return ret; + take_lock(driver->update); + if (!hmm_vma_range_done(vma, &range)) { + release_lock(driver->update); + goto again; + } + + // Use pfns array content to update device page table + + release_lock(driver->update); + return 0; + } + +The driver->update lock is the same lock that the driver takes inside its +update() callback. That lock must be held before hmm_vma_range_done() to avoid +any race with a concurrent CPU page table update. + +HMM implements all this on top of the mmu_notifier API because we wanted a +simpler API and also to be able to perform optimizations latter on like doing +concurrent device updates in multi-devices scenario. + +HMM also serves as an impedance mismatch between how CPU page table updates +are done (by CPU write to the page table and TLB flushes) and how devices +update their own page table. Device updates are a multi-step process. First, +appropriate commands are written to a buffer, then this buffer is scheduled for +execution on the device. It is only once the device has executed commands in +the buffer that the update is done. Creating and scheduling the update command +buffer can happen concurrently for multiple devices. Waiting for each device to +report commands as executed is serialized (there is no point in doing this +concurrently). + + +Represent and manage device memory from core kernel point of view +================================================================= + +Several different designs were tried to support device memory. First one used +a device specific data structure to keep information about migrated memory and +HMM hooked itself in various places of mm code to handle any access to +addresses that were backed by device memory. It turns out that this ended up +replicating most of the fields of struct page and also needed many kernel code +paths to be updated to understand this new kind of memory. + +Most kernel code paths never try to access the memory behind a page +but only care about struct page contents. Because of this, HMM switched to +directly using struct page for device memory which left most kernel code paths +unaware of the difference. We only need to make sure that no one ever tries to +map those pages from the CPU side. + +HMM provides a set of helpers to register and hotplug device memory as a new +region needing a struct page. This is offered through a very simple API:: + + struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, + struct device *device, + unsigned long size); + void hmm_devmem_remove(struct hmm_devmem *devmem); + +The hmm_devmem_ops is where most of the important things are:: + + struct hmm_devmem_ops { + void (*free)(struct hmm_devmem *devmem, struct page *page); + int (*fault)(struct hmm_devmem *devmem, + struct vm_area_struct *vma, + unsigned long addr, + struct page *page, + unsigned flags, + pmd_t *pmdp); + }; + +The first callback (free()) happens when the last reference on a device page is +dropped. This means the device page is now free and no longer used by anyone. +The second callback happens whenever the CPU tries to access a device page +which it cannot do. This second callback must trigger a migration back to +system memory. + + +Migration to and from device memory +=================================== + +Because the CPU cannot access device memory, migration must use the device DMA +engine to perform copy from and to device memory. For this we need a new +migration helper:: + + int migrate_vma(const struct migrate_vma_ops *ops, + struct vm_area_struct *vma, + unsigned long mentries, + unsigned long start, + unsigned long end, + unsigned long *src, + unsigned long *dst, + void *private); + +Unlike other migration functions it works on a range of virtual address, there +are two reasons for that. First, device DMA copy has a high setup overhead cost +and thus batching multiple pages is needed as otherwise the migration overhead +makes the whole exercise pointless. The second reason is because the +migration might be for a range of addresses the device is actively accessing. + +The migrate_vma_ops struct defines two callbacks. First one (alloc_and_copy()) +controls destination memory allocation and copy operation. Second one is there +to allow the device driver to perform cleanup operations after migration:: + + struct migrate_vma_ops { + void (*alloc_and_copy)(struct vm_area_struct *vma, + const unsigned long *src, + unsigned long *dst, + unsigned long start, + unsigned long end, + void *private); + void (*finalize_and_map)(struct vm_area_struct *vma, + const unsigned long *src, + const unsigned long *dst, + unsigned long start, + unsigned long end, + void *private); + }; + +It is important to stress that these migration helpers allow for holes in the +virtual address range. Some pages in the range might not be migrated for all +the usual reasons (page is pinned, page is locked, ...). This helper does not +fail but just skips over those pages. + +The alloc_and_copy() might decide to not migrate all pages in the +range (for reasons under the callback control). For those, the callback just +has to leave the corresponding dst entry empty. + +Finally, the migration of the struct page might fail (for file backed page) for +various reasons (failure to freeze reference, or update page cache, ...). If +that happens, then the finalize_and_map() can catch any pages that were not +migrated. Note those pages were still copied to a new page and thus we wasted +bandwidth but this is considered as a rare event and a price that we are +willing to pay to keep all the code simpler. + + +Memory cgroup (memcg) and rss accounting +======================================== + +For now device memory is accounted as any regular page in rss counters (either +anonymous if device page is used for anonymous, file if device page is used for +file backed page or shmem if device page is used for shared memory). This is a +deliberate choice to keep existing applications, that might start using device +memory without knowing about it, running unimpacted. + +A drawback is that the OOM killer might kill an application using a lot of +device memory and not a lot of regular system memory and thus not freeing much +system memory. We want to gather more real world experience on how applications +and system react under memory pressure in the presence of device memory before +deciding to account device memory differently. + + +Same decision was made for memory cgroup. Device memory pages are accounted +against same memory cgroup a regular page would be accounted to. This does +simplify migration to and from device memory. This also means that migration +back from device memory to regular memory cannot fail because it would +go above memory cgroup limit. We might revisit this choice latter on once we +get more experience in how device memory is used and its impact on memory +resource control. + + +Note that device memory can never be pinned by device driver nor through GUP +and thus such memory is always free upon process exit. Or when last reference +is dropped in case of shared memory or file backed memory. diff --git a/Documentation/vm/hmm.txt b/Documentation/vm/hmm.txt deleted file mode 100644 index 4d3aac9f4a5d..000000000000 --- a/Documentation/vm/hmm.txt +++ /dev/null @@ -1,384 +0,0 @@ -Heterogeneous Memory Management (HMM) - -Transparently allow any component of a program to use any memory region of said -program with a device without using device specific memory allocator. This is -becoming a requirement to simplify the use of advance heterogeneous computing -where GPU, DSP or FPGA are use to perform various computations. - -This document is divided as follow, in the first section i expose the problems -related to the use of a device specific allocator. The second section i expose -the hardware limitations that are inherent to many platforms. The third section -gives an overview of HMM designs. The fourth section explains how CPU page- -table mirroring works and what is HMM purpose in this context. Fifth section -deals with how device memory is represented inside the kernel. Finaly the last -section present the new migration helper that allow to leverage the device DMA -engine. - - -1) Problems of using device specific memory allocator: -2) System bus, device memory characteristics -3) Share address space and migration -4) Address space mirroring implementation and API -5) Represent and manage device memory from core kernel point of view -6) Migrate to and from device memory -7) Memory cgroup (memcg) and rss accounting - - -------------------------------------------------------------------------------- - -1) Problems of using device specific memory allocator: - -Device with large amount of on board memory (several giga bytes) like GPU have -historically manage their memory through dedicated driver specific API. This -creates a disconnect between memory allocated and managed by device driver and -regular application memory (private anonymous, share memory or regular file -back memory). From here on i will refer to this aspect as split address space. -I use share address space to refer to the opposite situation ie one in which -any memory region can be use by device transparently. - -Split address space because device can only access memory allocated through the -device specific API. This imply that all memory object in a program are not -equal from device point of view which complicate large program that rely on a -wide set of libraries. - -Concretly this means that code that wants to leverage device like GPU need to -copy object between genericly allocated memory (malloc, mmap private/share/) -and memory allocated through the device driver API (this still end up with an -mmap but of the device file). - -For flat dataset (array, grid, image, ...) this isn't too hard to achieve but -complex data-set (list, tree, ...) are hard to get right. Duplicating a complex -data-set need to re-map all the pointer relations between each of its elements. -This is error prone and program gets harder to debug because of the duplicate -data-set. - -Split address space also means that library can not transparently use data they -are getting from core program or other library and thus each library might have -to duplicate its input data-set using specific memory allocator. Large project -suffer from this and waste resources because of the various memory copy. - -Duplicating each library API to accept as input or output memory allocted by -each device specific allocator is not a viable option. It would lead to a -combinatorial explosions in the library entry points. - -Finaly with the advance of high level language constructs (in C++ but in other -language too) it is now possible for compiler to leverage GPU or other devices -without even the programmer knowledge. Some of compiler identified patterns are -only do-able with a share address. It is as well more reasonable to use a share -address space for all the other patterns. - - -------------------------------------------------------------------------------- - -2) System bus, device memory characteristics - -System bus cripple share address due to few limitations. Most system bus only -allow basic memory access from device to main memory, even cache coherency is -often optional. Access to device memory from CPU is even more limited, most -often than not it is not cache coherent. - -If we only consider the PCIE bus than device can access main memory (often -through an IOMMU) and be cache coherent with the CPUs. However it only allows -a limited set of atomic operation from device on main memory. This is worse -in the other direction the CPUs can only access a limited range of the device -memory and can not perform atomic operations on it. Thus device memory can not -be consider like regular memory from kernel point of view. - -Another crippling factor is the limited bandwidth (~32GBytes/s with PCIE 4.0 -and 16 lanes). This is 33 times less that fastest GPU memory (1 TBytes/s). -The final limitation is latency, access to main memory from the device has an -order of magnitude higher latency than when the device access its own memory. - -Some platform are developing new system bus or additions/modifications to PCIE -to address some of those limitations (OpenCAPI, CCIX). They mainly allow two -way cache coherency between CPU and device and allow all atomic operations the -architecture supports. Saddly not all platform are following this trends and -some major architecture are left without hardware solutions to those problems. - -So for share address space to make sense not only we must allow device to -access any memory memory but we must also permit any memory to be migrated to -device memory while device is using it (blocking CPU access while it happens). - - -------------------------------------------------------------------------------- - -3) Share address space and migration - -HMM intends to provide two main features. First one is to share the address -space by duplication the CPU page table into the device page table so same -address point to same memory and this for any valid main memory address in -the process address space. - -To achieve this, HMM offer a set of helpers to populate the device page table -while keeping track of CPU page table updates. Device page table updates are -not as easy as CPU page table updates. To update the device page table you must -allow a buffer (or use a pool of pre-allocated buffer) and write GPU specifics -commands in it to perform the update (unmap, cache invalidations and flush, -...). This can not be done through common code for all device. Hence why HMM -provides helpers to factor out everything that can be while leaving the gory -details to the device driver. - -The second mechanism HMM provide is a new kind of ZONE_DEVICE memory that does -allow to allocate a struct page for each page of the device memory. Those page -are special because the CPU can not map them. They however allow to migrate -main memory to device memory using exhisting migration mechanism and everything -looks like if page was swap out to disk from CPU point of view. Using a struct -page gives the easiest and cleanest integration with existing mm mechanisms. -Again here HMM only provide helpers, first to hotplug new ZONE_DEVICE memory -for the device memory and second to perform migration. Policy decision of what -and when to migrate things is left to the device driver. - -Note that any CPU access to a device page trigger a page fault and a migration -back to main memory ie when a page backing an given address A is migrated from -a main memory page to a device page then any CPU access to address A trigger a -page fault and initiate a migration back to main memory. - - -With this two features, HMM not only allow a device to mirror a process address -space and keeps both CPU and device page table synchronize, but also allow to -leverage device memory by migrating part of data-set that is actively use by a -device. - - -------------------------------------------------------------------------------- - -4) Address space mirroring implementation and API - -Address space mirroring main objective is to allow to duplicate range of CPU -page table into a device page table and HMM helps keeping both synchronize. A -device driver that want to mirror a process address space must start with the -registration of an hmm_mirror struct: - - int hmm_mirror_register(struct hmm_mirror *mirror, - struct mm_struct *mm); - int hmm_mirror_register_locked(struct hmm_mirror *mirror, - struct mm_struct *mm); - -The locked variant is to be use when the driver is already holding the mmap_sem -of the mm in write mode. The mirror struct has a set of callback that are use -to propagate CPU page table: - - struct hmm_mirror_ops { - /* sync_cpu_device_pagetables() - synchronize page tables - * - * @mirror: pointer to struct hmm_mirror - * @update_type: type of update that occurred to the CPU page table - * @start: virtual start address of the range to update - * @end: virtual end address of the range to update - * - * This callback ultimately originates from mmu_notifiers when the CPU - * page table is updated. The device driver must update its page table - * in response to this callback. The update argument tells what action - * to perform. - * - * The device driver must not return from this callback until the device - * page tables are completely updated (TLBs flushed, etc); this is a - * synchronous call. - */ - void (*update)(struct hmm_mirror *mirror, - enum hmm_update action, - unsigned long start, - unsigned long end); - }; - -Device driver must perform update to the range following action (turn range -read only, or fully unmap, ...). Once driver callback returns the device must -be done with the update. - - -When device driver wants to populate a range of virtual address it can use -either: - int hmm_vma_get_pfns(struct vm_area_struct *vma, - struct hmm_range *range, - unsigned long start, - unsigned long end, - hmm_pfn_t *pfns); - int hmm_vma_fault(struct vm_area_struct *vma, - struct hmm_range *range, - unsigned long start, - unsigned long end, - hmm_pfn_t *pfns, - bool write, - bool block); - -First one (hmm_vma_get_pfns()) will only fetch present CPU page table entry and -will not trigger a page fault on missing or non present entry. The second one -do trigger page fault on missing or read only entry if write parameter is true. -Page fault use the generic mm page fault code path just like a CPU page fault. - -Both function copy CPU page table into their pfns array argument. Each entry in -that array correspond to an address in the virtual range. HMM provide a set of -flags to help driver identify special CPU page table entries. - -Locking with the update() callback is the most important aspect the driver must -respect in order to keep things properly synchronize. The usage pattern is : - - int driver_populate_range(...) - { - struct hmm_range range; - ... - again: - ret = hmm_vma_get_pfns(vma, &range, start, end, pfns); - if (ret) - return ret; - take_lock(driver->update); - if (!hmm_vma_range_done(vma, &range)) { - release_lock(driver->update); - goto again; - } - - // Use pfns array content to update device page table - - release_lock(driver->update); - return 0; - } - -The driver->update lock is the same lock that driver takes inside its update() -callback. That lock must be call before hmm_vma_range_done() to avoid any race -with a concurrent CPU page table update. - -HMM implements all this on top of the mmu_notifier API because we wanted to a -simpler API and also to be able to perform optimization latter own like doing -concurrent device update in multi-devices scenario. - -HMM also serve as an impedence missmatch between how CPU page table update are -done (by CPU write to the page table and TLB flushes) from how device update -their own page table. Device update is a multi-step process, first appropriate -commands are write to a buffer, then this buffer is schedule for execution on -the device. It is only once the device has executed commands in the buffer that -the update is done. Creating and scheduling update command buffer can happen -concurrently for multiple devices. Waiting for each device to report commands -as executed is serialize (there is no point in doing this concurrently). - - -------------------------------------------------------------------------------- - -5) Represent and manage device memory from core kernel point of view - -Several differents design were try to support device memory. First one use -device specific data structure to keep information about migrated memory and -HMM hooked itself in various place of mm code to handle any access to address -that were back by device memory. It turns out that this ended up replicating -most of the fields of struct page and also needed many kernel code path to be -updated to understand this new kind of memory. - -Thing is most kernel code path never try to access the memory behind a page -but only care about struct page contents. Because of this HMM switchted to -directly using struct page for device memory which left most kernel code path -un-aware of the difference. We only need to make sure that no one ever try to -map those page from the CPU side. - -HMM provide a set of helpers to register and hotplug device memory as a new -region needing struct page. This is offer through a very simple API: - - struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, - struct device *device, - unsigned long size); - void hmm_devmem_remove(struct hmm_devmem *devmem); - -The hmm_devmem_ops is where most of the important things are: - - struct hmm_devmem_ops { - void (*free)(struct hmm_devmem *devmem, struct page *page); - int (*fault)(struct hmm_devmem *devmem, - struct vm_area_struct *vma, - unsigned long addr, - struct page *page, - unsigned flags, - pmd_t *pmdp); - }; - -The first callback (free()) happens when the last reference on a device page is -drop. This means the device page is now free and no longer use by anyone. The -second callback happens whenever CPU try to access a device page which it can -not do. This second callback must trigger a migration back to system memory. - - -------------------------------------------------------------------------------- - -6) Migrate to and from device memory - -Because CPU can not access device memory, migration must use device DMA engine -to perform copy from and to device memory. For this we need a new migration -helper: - - int migrate_vma(const struct migrate_vma_ops *ops, - struct vm_area_struct *vma, - unsigned long mentries, - unsigned long start, - unsigned long end, - unsigned long *src, - unsigned long *dst, - void *private); - -Unlike other migration function it works on a range of virtual address, there -is two reasons for that. First device DMA copy has a high setup overhead cost -and thus batching multiple pages is needed as otherwise the migration overhead -make the whole excersie pointless. The second reason is because driver trigger -such migration base on range of address the device is actively accessing. - -The migrate_vma_ops struct define two callbacks. First one (alloc_and_copy()) -control destination memory allocation and copy operation. Second one is there -to allow device driver to perform cleanup operation after migration. - - struct migrate_vma_ops { - void (*alloc_and_copy)(struct vm_area_struct *vma, - const unsigned long *src, - unsigned long *dst, - unsigned long start, - unsigned long end, - void *private); - void (*finalize_and_map)(struct vm_area_struct *vma, - const unsigned long *src, - const unsigned long *dst, - unsigned long start, - unsigned long end, - void *private); - }; - -It is important to stress that this migration helpers allow for hole in the -virtual address range. Some pages in the range might not be migrated for all -the usual reasons (page is pin, page is lock, ...). This helper does not fail -but just skip over those pages. - -The alloc_and_copy() might as well decide to not migrate all pages in the -range (for reasons under the callback control). For those the callback just -have to leave the corresponding dst entry empty. - -Finaly the migration of the struct page might fails (for file back page) for -various reasons (failure to freeze reference, or update page cache, ...). If -that happens then the finalize_and_map() can catch any pages that was not -migrated. Note those page were still copied to new page and thus we wasted -bandwidth but this is considered as a rare event and a price that we are -willing to pay to keep all the code simpler. - - -------------------------------------------------------------------------------- - -7) Memory cgroup (memcg) and rss accounting - -For now device memory is accounted as any regular page in rss counters (either -anonymous if device page is use for anonymous, file if device page is use for -file back page or shmem if device page is use for share memory). This is a -deliberate choice to keep existing application that might start using device -memory without knowing about it to keep runing unimpacted. - -Drawbacks is that OOM killer might kill an application using a lot of device -memory and not a lot of regular system memory and thus not freeing much system -memory. We want to gather more real world experience on how application and -system react under memory pressure in the presence of device memory before -deciding to account device memory differently. - - -Same decision was made for memory cgroup. Device memory page are accounted -against same memory cgroup a regular page would be accounted to. This does -simplify migration to and from device memory. This also means that migration -back from device memory to regular memory can not fail because it would -go above memory cgroup limit. We might revisit this choice latter on once we -get more experience in how device memory is use and its impact on memory -resource control. - - -Note that device memory can never be pin nor by device driver nor through GUP -and thus such memory is always free upon process exit. Or when last reference -is drop in case of share memory or file back memory. diff --git a/Documentation/vm/hugetlbfs_reserv.txt b/Documentation/vm/hugetlbfs_reserv.rst index 9aca09a76bed..9d200762114f 100644 --- a/Documentation/vm/hugetlbfs_reserv.txt +++ b/Documentation/vm/hugetlbfs_reserv.rst @@ -1,6 +1,13 @@ -Hugetlbfs Reservation Overview ------------------------------- -Huge pages as described at 'Documentation/vm/hugetlbpage.txt' are typically +.. _hugetlbfs_reserve: + +===================== +Hugetlbfs Reservation +===================== + +Overview +======== + +Huge pages as described at :ref:`hugetlbpage` are typically preallocated for application use. These huge pages are instantiated in a task's address space at page fault time if the VMA indicates huge pages are to be used. If no huge page exists at page fault time, the task is sent @@ -17,47 +24,55 @@ describe how huge page reserve processing is done in the v4.10 kernel. Audience --------- +======== This description is primarily targeted at kernel developers who are modifying hugetlbfs code. The Data Structures -------------------- +=================== + resv_huge_pages This is a global (per-hstate) count of reserved huge pages. Reserved huge pages are only available to the task which reserved them. Therefore, the number of huge pages generally available is computed - as (free_huge_pages - resv_huge_pages). + as (``free_huge_pages - resv_huge_pages``). Reserve Map - A reserve map is described by the structure: - struct resv_map { - struct kref refs; - spinlock_t lock; - struct list_head regions; - long adds_in_progress; - struct list_head region_cache; - long region_cache_count; - }; + A reserve map is described by the structure:: + + struct resv_map { + struct kref refs; + spinlock_t lock; + struct list_head regions; + long adds_in_progress; + struct list_head region_cache; + long region_cache_count; + }; + There is one reserve map for each huge page mapping in the system. The regions list within the resv_map describes the regions within - the mapping. A region is described as: - struct file_region { - struct list_head link; - long from; - long to; - }; + the mapping. A region is described as:: + + struct file_region { + struct list_head link; + long from; + long to; + }; + The 'from' and 'to' fields of the file region structure are huge page indices into the mapping. Depending on the type of mapping, a region in the reserv_map may indicate reservations exist for the range, or reservations do not exist. Flags for MAP_PRIVATE Reservations These are stored in the bottom bits of the reservation map pointer. - #define HPAGE_RESV_OWNER (1UL << 0) Indicates this task is the - owner of the reservations associated with the mapping. - #define HPAGE_RESV_UNMAPPED (1UL << 1) Indicates task originally - mapping this range (and creating reserves) has unmapped a - page from this task (the child) due to a failed COW. + + ``#define HPAGE_RESV_OWNER (1UL << 0)`` + Indicates this task is the owner of the reservations + associated with the mapping. + ``#define HPAGE_RESV_UNMAPPED (1UL << 1)`` + Indicates task originally mapping this range (and creating + reserves) has unmapped a page from this task (the child) + due to a failed COW. Page Flags The PagePrivate page flag is used to indicate that a huge page reservation must be restored when the huge page is freed. More @@ -65,12 +80,14 @@ Page Flags Reservation Map Location (Private or Shared) --------------------------------------------- +============================================ + A huge page mapping or segment is either private or shared. If private, it is typically only available to a single address space (task). If shared, it can be mapped into multiple address spaces (tasks). The location and semantics of the reservation map is significantly different for two types of mappings. Location differences are: + - For private mappings, the reservation map hangs off the the VMA structure. Specifically, vma->vm_private_data. This reserve map is created at the time the mapping (mmap(MAP_PRIVATE)) is created. @@ -82,15 +99,15 @@ of mappings. Location differences are: Creating Reservations ---------------------- +===================== Reservations are created when a huge page backed shared memory segment is created (shmget(SHM_HUGETLB)) or a mapping is created via mmap(MAP_HUGETLB). -These operations result in a call to the routine hugetlb_reserve_pages() +These operations result in a call to the routine hugetlb_reserve_pages():: -int hugetlb_reserve_pages(struct inode *inode, - long from, long to, - struct vm_area_struct *vma, - vm_flags_t vm_flags) + int hugetlb_reserve_pages(struct inode *inode, + long from, long to, + struct vm_area_struct *vma, + vm_flags_t vm_flags) The first thing hugetlb_reserve_pages() does is check for the NORESERVE flag was specified in either the shmget() or mmap() call. If NORESERVE @@ -105,6 +122,7 @@ the 'from' and 'to' arguments have been adjusted by this offset. One of the big differences between PRIVATE and SHARED mappings is the way in which reservations are represented in the reservation map. + - For shared mappings, an entry in the reservation map indicates a reservation exists or did exist for the corresponding page. As reservations are consumed, the reservation map is not modified. @@ -121,12 +139,13 @@ to indicate this VMA owns the reservations. The reservation map is consulted to determine how many huge page reservations are needed for the current mapping/segment. For private mappings, this is always the value (to - from). However, for shared mappings it is possible that some reservations may already exist within the range (to - from). See the -section "Reservation Map Modifications" for details on how this is accomplished. +section :ref:`Reservation Map Modifications <resv_map_modifications>` +for details on how this is accomplished. The mapping may be associated with a subpool. If so, the subpool is consulted to ensure there is sufficient space for the mapping. It is possible that the subpool has set aside reservations that can be used for the mapping. See the -section "Subpool Reservations" for more details. +section :ref:`Subpool Reservations <sub_pool_resv>` for more details. After consulting the reservation map and subpool, the number of needed new reservations is known. The routine hugetlb_acct_memory() is called to check @@ -135,9 +154,11 @@ calls into routines that potentially allocate and adjust surplus page counts. However, within those routines the code is simply checking to ensure there are enough free huge pages to accommodate the reservation. If there are, the global reservation count resv_huge_pages is adjusted something like the -following. +following:: + if (resv_needed <= (resv_huge_pages - free_huge_pages)) resv_huge_pages += resv_needed; + Note that the global lock hugetlb_lock is held when checking and adjusting these counters. @@ -152,14 +173,18 @@ If hugetlb_reserve_pages() was successful, the global reservation count and reservation map associated with the mapping will be modified as required to ensure reservations exist for the range 'from' - 'to'. +.. _consume_resv: Consuming Reservations/Allocating a Huge Page ---------------------------------------------- +============================================= + Reservations are consumed when huge pages associated with the reservations are allocated and instantiated in the corresponding mapping. The allocation -is performed within the routine alloc_huge_page(). -struct page *alloc_huge_page(struct vm_area_struct *vma, - unsigned long addr, int avoid_reserve) +is performed within the routine alloc_huge_page():: + + struct page *alloc_huge_page(struct vm_area_struct *vma, + unsigned long addr, int avoid_reserve) + alloc_huge_page is passed a VMA pointer and a virtual address, so it can consult the reservation map to determine if a reservation exists. In addition, alloc_huge_page takes the argument avoid_reserve which indicates reserves @@ -170,8 +195,9 @@ page are being allocated. The helper routine vma_needs_reservation() is called to determine if a reservation exists for the address within the mapping(vma). See the section -"Reservation Map Helper Routines" for detailed information on what this -routine does. The value returned from vma_needs_reservation() is generally +:ref:`Reservation Map Helper Routines <resv_map_helpers>` for detailed +information on what this routine does. +The value returned from vma_needs_reservation() is generally 0 or 1. 0 if a reservation exists for the address, 1 if no reservation exists. If a reservation does not exist, and there is a subpool associated with the mapping the subpool is consulted to determine if it contains reservations. @@ -180,21 +206,25 @@ However, in every case the avoid_reserve argument overrides the use of a reservation for the allocation. After determining whether a reservation exists and can be used for the allocation, the routine dequeue_huge_page_vma() is called. This routine takes two arguments related to reservations: + - avoid_reserve, this is the same value/argument passed to alloc_huge_page() - chg, even though this argument is of type long only the values 0 or 1 are passed to dequeue_huge_page_vma. If the value is 0, it indicates a reservation exists (see the section "Memory Policy and Reservations" for possible issues). If the value is 1, it indicates a reservation does not exist and the page must be taken from the global free pool if possible. + The free lists associated with the memory policy of the VMA are searched for a free page. If a page is found, the value free_huge_pages is decremented when the page is removed from the free list. If there was a reservation -associated with the page, the following adjustments are made: +associated with the page, the following adjustments are made:: + SetPagePrivate(page); /* Indicates allocating this page consumed * a reservation, and if an error is * encountered such that the page must be * freed, the reservation will be restored. */ resv_huge_pages--; /* Decrement the global reservation count */ + Note, if no huge page can be found that satisfies the VMA's memory policy an attempt will be made to allocate one using the buddy allocator. This brings up the issue of surplus huge pages and overcommit which is beyond @@ -222,12 +252,14 @@ mapping. In such cases, the reservation count and subpool free page count will be off by one. This rare condition can be identified by comparing the return value from vma_needs_reservation and vma_commit_reservation. If such a race is detected, the subpool and global reserve counts are adjusted to -compensate. See the section "Reservation Map Helper Routines" for more +compensate. See the section +:ref:`Reservation Map Helper Routines <resv_map_helpers>` for more information on these routines. Instantiate Huge Pages ----------------------- +====================== + After huge page allocation, the page is typically added to the page tables of the allocating task. Before this, pages in a shared mapping are added to the page cache and pages in private mappings are added to an anonymous @@ -237,7 +269,8 @@ to the global reservation count (resv_huge_pages). Freeing Huge Pages ------------------- +================== + Huge page freeing is performed by the routine free_huge_page(). This routine is the destructor for hugetlbfs compound pages. As a result, it is only passed a pointer to the page struct. When a huge page is freed, reservation @@ -247,7 +280,8 @@ on an error path where a global reserve count must be restored. The page->private field points to any subpool associated with the page. If the PagePrivate flag is set, it indicates the global reserve count should -be adjusted (see the section "Consuming Reservations/Allocating a Huge Page" +be adjusted (see the section +:ref:`Consuming Reservations/Allocating a Huge Page <consume_resv>` for information on how these are set). The routine first calls hugepage_subpool_put_pages() for the page. If this @@ -259,9 +293,11 @@ Therefore, the global resv_huge_pages counter is incremented in this case. If the PagePrivate flag was set in the page, the global resv_huge_pages counter will always be incremented. +.. _sub_pool_resv: Subpool Reservations --------------------- +==================== + There is a struct hstate associated with each huge page size. The hstate tracks all huge pages of the specified size. A subpool represents a subset of pages within a hstate that is associated with a mounted hugetlbfs @@ -295,7 +331,8 @@ the global pools. COW and Reservations --------------------- +==================== + Since shared mappings all point to and use the same underlying pages, the biggest reservation concern for COW is private mappings. In this case, two tasks can be pointing at the same previously allocated page. One task @@ -326,30 +363,36 @@ faults on a non-present page. But, the original owner of the mapping/reservation will behave as expected. +.. _resv_map_modifications: + Reservation Map Modifications ------------------------------ +============================= + The following low level routines are used to make modifications to a reservation map. Typically, these routines are not called directly. Rather, a reservation map helper routine is called which calls one of these low level routines. These low level routines are fairly well documented in the source -code (mm/hugetlb.c). These routines are: -long region_chg(struct resv_map *resv, long f, long t); -long region_add(struct resv_map *resv, long f, long t); -void region_abort(struct resv_map *resv, long f, long t); -long region_count(struct resv_map *resv, long f, long t); +code (mm/hugetlb.c). These routines are:: + + long region_chg(struct resv_map *resv, long f, long t); + long region_add(struct resv_map *resv, long f, long t); + void region_abort(struct resv_map *resv, long f, long t); + long region_count(struct resv_map *resv, long f, long t); Operations on the reservation map typically involve two operations: + 1) region_chg() is called to examine the reserve map and determine how many pages in the specified range [f, t) are NOT currently represented. The calling code performs global checks and allocations to determine if there are enough huge pages for the operation to succeed. -2a) If the operation can succeed, region_add() is called to actually modify - the reservation map for the same range [f, t) previously passed to - region_chg(). -2b) If the operation can not succeed, region_abort is called for the same range - [f, t) to abort the operation. +2) + a) If the operation can succeed, region_add() is called to actually modify + the reservation map for the same range [f, t) previously passed to + region_chg(). + b) If the operation can not succeed, region_abort is called for the same + range [f, t) to abort the operation. Note that this is a two step process where region_add() and region_abort() are guaranteed to succeed after a prior call to region_chg() for the same @@ -371,6 +414,7 @@ and make the appropriate adjustments. The routine region_del() is called to remove regions from a reservation map. It is typically called in the following situations: + - When a file in the hugetlbfs filesystem is being removed, the inode will be released and the reservation map freed. Before freeing the reservation map, all the individual file_region structures must be freed. In this case @@ -384,6 +428,7 @@ It is typically called in the following situations: removed, region_del() is called to remove the corresponding entry from the reservation map. In this case, region_del is passed the range [page_idx, page_idx + 1). + In every case, region_del() will return the number of pages removed from the reservation map. In VERY rare cases, region_del() can fail. This can only happen in the hole punch case where it has to split an existing file_region @@ -403,9 +448,11 @@ outstanding (outstanding = (end - start) - region_count(resv, start, end)). Since the mapping is going away, the subpool and global reservation counts are decremented by the number of outstanding reservations. +.. _resv_map_helpers: Reservation Map Helper Routines -------------------------------- +=============================== + Several helper routines exist to query and modify the reservation maps. These routines are only interested with reservations for a specific huge page, so they just pass in an address instead of a range. In addition, @@ -414,32 +461,40 @@ or shared) and the location of the reservation map (inode or VMA) can be determined. These routines simply call the underlying routines described in the section "Reservation Map Modifications". However, they do take into account the 'opposite' meaning of reservation map entries for private and -shared mappings and hide this detail from the caller. +shared mappings and hide this detail from the caller:: + + long vma_needs_reservation(struct hstate *h, + struct vm_area_struct *vma, + unsigned long addr) -long vma_needs_reservation(struct hstate *h, - struct vm_area_struct *vma, unsigned long addr) This routine calls region_chg() for the specified page. If no reservation -exists, 1 is returned. If a reservation exists, 0 is returned. +exists, 1 is returned. If a reservation exists, 0 is returned:: + + long vma_commit_reservation(struct hstate *h, + struct vm_area_struct *vma, + unsigned long addr) -long vma_commit_reservation(struct hstate *h, - struct vm_area_struct *vma, unsigned long addr) This calls region_add() for the specified page. As in the case of region_chg and region_add, this routine is to be called after a previous call to vma_needs_reservation. It will add a reservation entry for the page. It returns 1 if the reservation was added and 0 if not. The return value should be compared with the return value of the previous call to vma_needs_reservation. An unexpected difference indicates the reservation -map was modified between calls. +map was modified between calls:: + + void vma_end_reservation(struct hstate *h, + struct vm_area_struct *vma, + unsigned long addr) -void vma_end_reservation(struct hstate *h, - struct vm_area_struct *vma, unsigned long addr) This calls region_abort() for the specified page. As in the case of region_chg and region_abort, this routine is to be called after a previous call to vma_needs_reservation. It will abort/end the in progress reservation add -operation. +operation:: + + long vma_add_reservation(struct hstate *h, + struct vm_area_struct *vma, + unsigned long addr) -long vma_add_reservation(struct hstate *h, - struct vm_area_struct *vma, unsigned long addr) This is a special wrapper routine to help facilitate reservation cleanup on error paths. It is only called from the routine restore_reserve_on_error(). This routine is used in conjunction with vma_needs_reservation in an attempt @@ -453,8 +508,10 @@ be done on error paths. Reservation Cleanup in Error Paths ----------------------------------- -As mentioned in the section "Reservation Map Helper Routines", reservation +================================== + +As mentioned in the section +:ref:`Reservation Map Helper Routines <resv_map_helpers>`, reservation map modifications are performed in two steps. First vma_needs_reservation is called before a page is allocated. If the allocation is successful, then vma_commit_reservation is called. If not, vma_end_reservation is called. @@ -494,13 +551,14 @@ so that a reservation will not be leaked when the huge page is freed. Reservations and Memory Policy ------------------------------- +============================== Per-node huge page lists existed in struct hstate when git was first used to manage Linux code. The concept of reservations was added some time later. When reservations were added, no attempt was made to take memory policy into account. While cpusets are not exactly the same as memory policy, this comment in hugetlb_acct_memory sums up the interaction between reservations -and cpusets/memory policy. +and cpusets/memory policy:: + /* * When cpuset is configured, it breaks the strict hugetlb page * reservation as the accounting is done on a global variable. Such @@ -525,5 +583,13 @@ of cpusets or memory policy there is no guarantee that huge pages will be available on the required nodes. This is true even if there are a sufficient number of global reservations. +Hugetlbfs regression testing +============================ + +The most complete set of hugetlb tests are in the libhugetlbfs repository. +If you modify any hugetlb related code, use the libhugetlbfs test suite +to check for regressions. In addition, if you add any new hugetlb +functionality, please add appropriate tests to libhugetlbfs. +-- Mike Kravetz, 7 April 2017 diff --git a/Documentation/vm/hwpoison.txt b/Documentation/vm/hwpoison.rst index e912d7eee769..09bd24a92784 100644 --- a/Documentation/vm/hwpoison.txt +++ b/Documentation/vm/hwpoison.rst @@ -1,7 +1,14 @@ +.. hwpoison: + +======== +hwpoison +======== + What is hwpoison? +================= Upcoming Intel CPUs have support for recovering from some memory errors -(``MCA recovery''). This requires the OS to declare a page "poisoned", +(``MCA recovery``). This requires the OS to declare a page "poisoned", kill the processes associated with it and avoid using it in the future. This patchkit implements the necessary infrastructure in the VM. @@ -46,9 +53,10 @@ address. This in theory allows other applications to handle memory failures too. The expection is that near all applications won't do that, but some very specialized ones might. ---- +Failure recovery modes +====================== -There are two (actually three) modi memory failure recovery can be in: +There are two (actually three) modes memory failure recovery can be in: vm.memory_failure_recovery sysctl set to zero: All memory failures cause a panic. Do not attempt recovery. @@ -67,9 +75,8 @@ late kill This is best for memory error unaware applications and default Note some pages are always handled as late kill. ---- - -User control: +User control +============ vm.memory_failure_recovery See sysctl.txt @@ -79,11 +86,19 @@ vm.memory_failure_early_kill PR_MCE_KILL Set early/late kill mode/revert to system default - arg1: PR_MCE_KILL_CLEAR: Revert to system default - arg1: PR_MCE_KILL_SET: arg2 defines thread specific mode - PR_MCE_KILL_EARLY: Early kill - PR_MCE_KILL_LATE: Late kill - PR_MCE_KILL_DEFAULT: Use system global default + + arg1: PR_MCE_KILL_CLEAR: + Revert to system default + arg1: PR_MCE_KILL_SET: + arg2 defines thread specific mode + + PR_MCE_KILL_EARLY: + Early kill + PR_MCE_KILL_LATE: + Late kill + PR_MCE_KILL_DEFAULT + Use system global default + Note that if you want to have a dedicated thread which handles the SIGBUS(BUS_MCEERR_AO) on behalf of the process, you should call prctl(PR_MCE_KILL_EARLY) on the designated thread. Otherwise, @@ -92,77 +107,64 @@ PR_MCE_KILL PR_MCE_KILL_GET return current mode +Testing +======= ---- - -Testing: - -madvise(MADV_HWPOISON, ....) - (as root) - Poison a page in the process for testing - +* madvise(MADV_HWPOISON, ....) (as root) - Poison a page in the + process for testing -hwpoison-inject module through debugfs +* hwpoison-inject module through debugfs ``/sys/kernel/debug/hwpoison/`` -/sys/kernel/debug/hwpoison/ + corrupt-pfn + Inject hwpoison fault at PFN echoed into this file. This does + some early filtering to avoid corrupted unintended pages in test suites. -corrupt-pfn + unpoison-pfn + Software-unpoison page at PFN echoed into this file. This way + a page can be reused again. This only works for Linux + injected failures, not for real memory failures. -Inject hwpoison fault at PFN echoed into this file. This does -some early filtering to avoid corrupted unintended pages in test suites. + Note these injection interfaces are not stable and might change between + kernel versions -unpoison-pfn + corrupt-filter-dev-major, corrupt-filter-dev-minor + Only handle memory failures to pages associated with the file + system defined by block device major/minor. -1U is the + wildcard value. This should be only used for testing with + artificial injection. -Software-unpoison page at PFN echoed into this file. This -way a page can be reused again. -This only works for Linux injected failures, not for real -memory failures. + corrupt-filter-memcg + Limit injection to pages owned by memgroup. Specified by inode + number of the memcg. -Note these injection interfaces are not stable and might change between -kernel versions + Example:: -corrupt-filter-dev-major -corrupt-filter-dev-minor + mkdir /sys/fs/cgroup/mem/hwpoison -Only handle memory failures to pages associated with the file system defined -by block device major/minor. -1U is the wildcard value. -This should be only used for testing with artificial injection. + usemem -m 100 -s 1000 & + echo `jobs -p` > /sys/fs/cgroup/mem/hwpoison/tasks -corrupt-filter-memcg + memcg_ino=$(ls -id /sys/fs/cgroup/mem/hwpoison | cut -f1 -d' ') + echo $memcg_ino > /debug/hwpoison/corrupt-filter-memcg -Limit injection to pages owned by memgroup. Specified by inode number -of the memcg. + page-types -p `pidof init` --hwpoison # shall do nothing + page-types -p `pidof usemem` --hwpoison # poison its pages -Example: - mkdir /sys/fs/cgroup/mem/hwpoison + corrupt-filter-flags-mask, corrupt-filter-flags-value + When specified, only poison pages if ((page_flags & mask) == + value). This allows stress testing of many kinds of + pages. The page_flags are the same as in /proc/kpageflags. The + flag bits are defined in include/linux/kernel-page-flags.h and + documented in Documentation/admin-guide/mm/pagemap.rst - usemem -m 100 -s 1000 & - echo `jobs -p` > /sys/fs/cgroup/mem/hwpoison/tasks +* Architecture specific MCE injector - memcg_ino=$(ls -id /sys/fs/cgroup/mem/hwpoison | cut -f1 -d' ') - echo $memcg_ino > /debug/hwpoison/corrupt-filter-memcg + x86 has mce-inject, mce-test - page-types -p `pidof init` --hwpoison # shall do nothing - page-types -p `pidof usemem` --hwpoison # poison its pages + Some portable hwpoison test programs in mce-test, see below. -corrupt-filter-flags-mask -corrupt-filter-flags-value - -When specified, only poison pages if ((page_flags & mask) == value). -This allows stress testing of many kinds of pages. The page_flags -are the same as in /proc/kpageflags. The flag bits are defined in -include/linux/kernel-page-flags.h and documented in -Documentation/vm/pagemap.txt - -Architecture specific MCE injector - -x86 has mce-inject, mce-test - -Some portable hwpoison test programs in mce-test, see blow. - ---- - -References: +References +========== http://halobates.de/mce-lc09-2.pdf Overview presentation from LinuxCon 09 @@ -174,14 +176,11 @@ git://git.kernel.org/pub/scm/utils/cpu/mce/mce-inject.git x86 specific injector ---- - -Limitations: - +Limitations +=========== - Not all page types are supported and never will. Most kernel internal -objects cannot be recovered, only LRU pages for now. + objects cannot be recovered, only LRU pages for now. - Right now hugepage support is missing. --- Andi Kleen, Oct 2009 - diff --git a/Documentation/vm/index.rst b/Documentation/vm/index.rst new file mode 100644 index 000000000000..c4ded22197ca --- /dev/null +++ b/Documentation/vm/index.rst @@ -0,0 +1,50 @@ +===================================== +Linux Memory Management Documentation +===================================== + +This is a collection of documents about Linux memory management (mm) subsystem. + +User guides for MM features +=========================== + +The following documents provide guides for controlling and tuning +various features of the Linux memory management + +.. toctree:: + :maxdepth: 1 + + swap_numa + zswap + +Kernel developers MM documentation +================================== + +The below documents describe MM internals with different level of +details ranging from notes and mailing list responses to elaborate +descriptions of data structures and algorithms. + +.. toctree:: + :maxdepth: 1 + + active_mm + balance + cleancache + frontswap + highmem + hmm + hwpoison + hugetlbfs_reserv + ksm + mmu_notifier + numa + overcommit-accounting + page_migration + page_frags + page_owner + remap_file_pages + slub + split_page_table_lock + transhuge + unevictable-lru + z3fold + zsmalloc diff --git a/Documentation/vm/ksm.rst b/Documentation/vm/ksm.rst new file mode 100644 index 000000000000..d32016d9be2c --- /dev/null +++ b/Documentation/vm/ksm.rst @@ -0,0 +1,87 @@ +.. _ksm: + +======================= +Kernel Samepage Merging +======================= + +KSM is a memory-saving de-duplication feature, enabled by CONFIG_KSM=y, +added to the Linux kernel in 2.6.32. See ``mm/ksm.c`` for its implementation, +and http://lwn.net/Articles/306704/ and http://lwn.net/Articles/330589/ + +The userspace interface of KSM is described in :ref:`Documentation/admin-guide/mm/ksm.rst <admin_guide_ksm>` + +Design +====== + +Overview +-------- + +.. kernel-doc:: mm/ksm.c + :DOC: Overview + +Reverse mapping +--------------- +KSM maintains reverse mapping information for KSM pages in the stable +tree. + +If a KSM page is shared between less than ``max_page_sharing`` VMAs, +the node of the stable tree that represents such KSM page points to a +list of :c:type:`struct rmap_item` and the ``page->mapping`` of the +KSM page points to the stable tree node. + +When the sharing passes this threshold, KSM adds a second dimension to +the stable tree. The tree node becomes a "chain" that links one or +more "dups". Each "dup" keeps reverse mapping information for a KSM +page with ``page->mapping`` pointing to that "dup". + +Every "chain" and all "dups" linked into a "chain" enforce the +invariant that they represent the same write protected memory content, +even if each "dup" will be pointed by a different KSM page copy of +that content. + +This way the stable tree lookup computational complexity is unaffected +if compared to an unlimited list of reverse mappings. It is still +enforced that there cannot be KSM page content duplicates in the +stable tree itself. + +The deduplication limit enforced by ``max_page_sharing`` is required +to avoid the virtual memory rmap lists to grow too large. The rmap +walk has O(N) complexity where N is the number of rmap_items +(i.e. virtual mappings) that are sharing the page, which is in turn +capped by ``max_page_sharing``. So this effectively spreads the linear +O(N) computational complexity from rmap walk context over different +KSM pages. The ksmd walk over the stable_node "chains" is also O(N), +but N is the number of stable_node "dups", not the number of +rmap_items, so it has not a significant impact on ksmd performance. In +practice the best stable_node "dup" candidate will be kept and found +at the head of the "dups" list. + +High values of ``max_page_sharing`` result in faster memory merging +(because there will be fewer stable_node dups queued into the +stable_node chain->hlist to check for pruning) and higher +deduplication factor at the expense of slower worst case for rmap +walks for any KSM page which can happen during swapping, compaction, +NUMA balancing and page migration. + +The ``stable_node_dups/stable_node_chains`` ratio is also affected by the +``max_page_sharing`` tunable, and an high ratio may indicate fragmentation +in the stable_node dups, which could be solved by introducing +fragmentation algorithms in ksmd which would refile rmap_items from +one stable_node dup to another stable_node dup, in order to free up +stable_node "dups" with few rmap_items in them, but that may increase +the ksmd CPU usage and possibly slowdown the readonly computations on +the KSM pages of the applications. + +The whole list of stable_node "dups" linked in the stable_node +"chains" is scanned periodically in order to prune stale stable_nodes. +The frequency of such scans is defined by +``stable_node_chains_prune_millisecs`` sysfs tunable. + +Reference +--------- +.. kernel-doc:: mm/ksm.c + :functions: mm_slot ksm_scan stable_node rmap_item + +-- +Izik Eidus, +Hugh Dickins, 17 Nov 2009 diff --git a/Documentation/vm/ksm.txt b/Documentation/vm/ksm.txt deleted file mode 100644 index 6686bd267dc9..000000000000 --- a/Documentation/vm/ksm.txt +++ /dev/null @@ -1,178 +0,0 @@ -How to use the Kernel Samepage Merging feature ----------------------------------------------- - -KSM is a memory-saving de-duplication feature, enabled by CONFIG_KSM=y, -added to the Linux kernel in 2.6.32. See mm/ksm.c for its implementation, -and http://lwn.net/Articles/306704/ and http://lwn.net/Articles/330589/ - -The KSM daemon ksmd periodically scans those areas of user memory which -have been registered with it, looking for pages of identical content which -can be replaced by a single write-protected page (which is automatically -copied if a process later wants to update its content). - -KSM was originally developed for use with KVM (where it was known as -Kernel Shared Memory), to fit more virtual machines into physical memory, -by sharing the data common between them. But it can be useful to any -application which generates many instances of the same data. - -KSM only merges anonymous (private) pages, never pagecache (file) pages. -KSM's merged pages were originally locked into kernel memory, but can now -be swapped out just like other user pages (but sharing is broken when they -are swapped back in: ksmd must rediscover their identity and merge again). - -KSM only operates on those areas of address space which an application -has advised to be likely candidates for merging, by using the madvise(2) -system call: int madvise(addr, length, MADV_MERGEABLE). - -The app may call int madvise(addr, length, MADV_UNMERGEABLE) to cancel -that advice and restore unshared pages: whereupon KSM unmerges whatever -it merged in that range. Note: this unmerging call may suddenly require -more memory than is available - possibly failing with EAGAIN, but more -probably arousing the Out-Of-Memory killer. - -If KSM is not configured into the running kernel, madvise MADV_MERGEABLE -and MADV_UNMERGEABLE simply fail with EINVAL. If the running kernel was -built with CONFIG_KSM=y, those calls will normally succeed: even if the -the KSM daemon is not currently running, MADV_MERGEABLE still registers -the range for whenever the KSM daemon is started; even if the range -cannot contain any pages which KSM could actually merge; even if -MADV_UNMERGEABLE is applied to a range which was never MADV_MERGEABLE. - -If a region of memory must be split into at least one new MADV_MERGEABLE -or MADV_UNMERGEABLE region, the madvise may return ENOMEM if the process -will exceed vm.max_map_count (see Documentation/sysctl/vm.txt). - -Like other madvise calls, they are intended for use on mapped areas of -the user address space: they will report ENOMEM if the specified range -includes unmapped gaps (though working on the intervening mapped areas), -and might fail with EAGAIN if not enough memory for internal structures. - -Applications should be considerate in their use of MADV_MERGEABLE, -restricting its use to areas likely to benefit. KSM's scans may use a lot -of processing power: some installations will disable KSM for that reason. - -The KSM daemon is controlled by sysfs files in /sys/kernel/mm/ksm/, -readable by all but writable only by root: - -pages_to_scan - how many present pages to scan before ksmd goes to sleep - e.g. "echo 100 > /sys/kernel/mm/ksm/pages_to_scan" - Default: 100 (chosen for demonstration purposes) - -sleep_millisecs - how many milliseconds ksmd should sleep before next scan - e.g. "echo 20 > /sys/kernel/mm/ksm/sleep_millisecs" - Default: 20 (chosen for demonstration purposes) - -merge_across_nodes - specifies if pages from different numa nodes can be merged. - When set to 0, ksm merges only pages which physically - reside in the memory area of same NUMA node. That brings - lower latency to access of shared pages. Systems with more - nodes, at significant NUMA distances, are likely to benefit - from the lower latency of setting 0. Smaller systems, which - need to minimize memory usage, are likely to benefit from - the greater sharing of setting 1 (default). You may wish to - compare how your system performs under each setting, before - deciding on which to use. merge_across_nodes setting can be - changed only when there are no ksm shared pages in system: - set run 2 to unmerge pages first, then to 1 after changing - merge_across_nodes, to remerge according to the new setting. - Default: 1 (merging across nodes as in earlier releases) - -run - set 0 to stop ksmd from running but keep merged pages, - set 1 to run ksmd e.g. "echo 1 > /sys/kernel/mm/ksm/run", - set 2 to stop ksmd and unmerge all pages currently merged, - but leave mergeable areas registered for next run - Default: 0 (must be changed to 1 to activate KSM, - except if CONFIG_SYSFS is disabled) - -use_zero_pages - specifies whether empty pages (i.e. allocated pages - that only contain zeroes) should be treated specially. - When set to 1, empty pages are merged with the kernel - zero page(s) instead of with each other as it would - happen normally. This can improve the performance on - architectures with coloured zero pages, depending on - the workload. Care should be taken when enabling this - setting, as it can potentially degrade the performance - of KSM for some workloads, for example if the checksums - of pages candidate for merging match the checksum of - an empty page. This setting can be changed at any time, - it is only effective for pages merged after the change. - Default: 0 (normal KSM behaviour as in earlier releases) - -max_page_sharing - Maximum sharing allowed for each KSM page. This - enforces a deduplication limit to avoid the virtual - memory rmap lists to grow too large. The minimum - value is 2 as a newly created KSM page will have at - least two sharers. The rmap walk has O(N) - complexity where N is the number of rmap_items - (i.e. virtual mappings) that are sharing the page, - which is in turn capped by max_page_sharing. So - this effectively spread the the linear O(N) - computational complexity from rmap walk context - over different KSM pages. The ksmd walk over the - stable_node "chains" is also O(N), but N is the - number of stable_node "dups", not the number of - rmap_items, so it has not a significant impact on - ksmd performance. In practice the best stable_node - "dup" candidate will be kept and found at the head - of the "dups" list. The higher this value the - faster KSM will merge the memory (because there - will be fewer stable_node dups queued into the - stable_node chain->hlist to check for pruning) and - the higher the deduplication factor will be, but - the slowest the worst case rmap walk could be for - any given KSM page. Slowing down the rmap_walk - means there will be higher latency for certain - virtual memory operations happening during - swapping, compaction, NUMA balancing and page - migration, in turn decreasing responsiveness for - the caller of those virtual memory operations. The - scheduler latency of other tasks not involved with - the VM operations doing the rmap walk is not - affected by this parameter as the rmap walks are - always schedule friendly themselves. - -stable_node_chains_prune_millisecs - How frequently to walk the whole - list of stable_node "dups" linked in the - stable_node "chains" in order to prune stale - stable_nodes. Smaller milllisecs values will free - up the KSM metadata with lower latency, but they - will make ksmd use more CPU during the scan. This - only applies to the stable_node chains so it's a - noop if not a single KSM page hit the - max_page_sharing yet (there would be no stable_node - chains in such case). - -The effectiveness of KSM and MADV_MERGEABLE is shown in /sys/kernel/mm/ksm/: - -pages_shared - how many shared pages are being used -pages_sharing - how many more sites are sharing them i.e. how much saved -pages_unshared - how many pages unique but repeatedly checked for merging -pages_volatile - how many pages changing too fast to be placed in a tree -full_scans - how many times all mergeable areas have been scanned - -stable_node_chains - number of stable node chains allocated, this is - effectively the number of KSM pages that hit the - max_page_sharing limit -stable_node_dups - number of stable node dups queued into the - stable_node chains - -A high ratio of pages_sharing to pages_shared indicates good sharing, but -a high ratio of pages_unshared to pages_sharing indicates wasted effort. -pages_volatile embraces several different kinds of activity, but a high -proportion there would also indicate poor use of madvise MADV_MERGEABLE. - -The maximum possible page_sharing/page_shared ratio is limited by the -max_page_sharing tunable. To increase the ratio max_page_sharing must -be increased accordingly. - -The stable_node_dups/stable_node_chains ratio is also affected by the -max_page_sharing tunable, and an high ratio may indicate fragmentation -in the stable_node dups, which could be solved by introducing -fragmentation algorithms in ksmd which would refile rmap_items from -one stable_node dup to another stable_node dup, in order to freeup -stable_node "dups" with few rmap_items in them, but that may increase -the ksmd CPU usage and possibly slowdown the readonly computations on -the KSM pages of the applications. - -Izik Eidus, -Hugh Dickins, 17 Nov 2009 diff --git a/Documentation/vm/mmu_notifier.rst b/Documentation/vm/mmu_notifier.rst new file mode 100644 index 000000000000..47baa1cf28c5 --- /dev/null +++ b/Documentation/vm/mmu_notifier.rst @@ -0,0 +1,99 @@ +.. _mmu_notifier: + +When do you need to notify inside page table lock ? +=================================================== + +When clearing a pte/pmd we are given a choice to notify the event through +(notify version of \*_clear_flush call mmu_notifier_invalidate_range) under +the page table lock. But that notification is not necessary in all cases. + +For secondary TLB (non CPU TLB) like IOMMU TLB or device TLB (when device use +thing like ATS/PASID to get the IOMMU to walk the CPU page table to access a +process virtual address space). There is only 2 cases when you need to notify +those secondary TLB while holding page table lock when clearing a pte/pmd: + + A) page backing address is free before mmu_notifier_invalidate_range_end() + B) a page table entry is updated to point to a new page (COW, write fault + on zero page, __replace_page(), ...) + +Case A is obvious you do not want to take the risk for the device to write to +a page that might now be used by some completely different task. + +Case B is more subtle. For correctness it requires the following sequence to +happen: + + - take page table lock + - clear page table entry and notify ([pmd/pte]p_huge_clear_flush_notify()) + - set page table entry to point to new page + +If clearing the page table entry is not followed by a notify before setting +the new pte/pmd value then you can break memory model like C11 or C++11 for +the device. + +Consider the following scenario (device use a feature similar to ATS/PASID): + +Two address addrA and addrB such that \|addrA - addrB\| >= PAGE_SIZE we assume +they are write protected for COW (other case of B apply too). + +:: + + [Time N] -------------------------------------------------------------------- + CPU-thread-0 {try to write to addrA} + CPU-thread-1 {try to write to addrB} + CPU-thread-2 {} + CPU-thread-3 {} + DEV-thread-0 {read addrA and populate device TLB} + DEV-thread-2 {read addrB and populate device TLB} + [Time N+1] ------------------------------------------------------------------ + CPU-thread-0 {COW_step0: {mmu_notifier_invalidate_range_start(addrA)}} + CPU-thread-1 {COW_step0: {mmu_notifier_invalidate_range_start(addrB)}} + CPU-thread-2 {} + CPU-thread-3 {} + DEV-thread-0 {} + DEV-thread-2 {} + [Time N+2] ------------------------------------------------------------------ + CPU-thread-0 {COW_step1: {update page table to point to new page for addrA}} + CPU-thread-1 {COW_step1: {update page table to point to new page for addrB}} + CPU-thread-2 {} + CPU-thread-3 {} + DEV-thread-0 {} + DEV-thread-2 {} + [Time N+3] ------------------------------------------------------------------ + CPU-thread-0 {preempted} + CPU-thread-1 {preempted} + CPU-thread-2 {write to addrA which is a write to new page} + CPU-thread-3 {} + DEV-thread-0 {} + DEV-thread-2 {} + [Time N+3] ------------------------------------------------------------------ + CPU-thread-0 {preempted} + CPU-thread-1 {preempted} + CPU-thread-2 {} + CPU-thread-3 {write to addrB which is a write to new page} + DEV-thread-0 {} + DEV-thread-2 {} + [Time N+4] ------------------------------------------------------------------ + CPU-thread-0 {preempted} + CPU-thread-1 {COW_step3: {mmu_notifier_invalidate_range_end(addrB)}} + CPU-thread-2 {} + CPU-thread-3 {} + DEV-thread-0 {} + DEV-thread-2 {} + [Time N+5] ------------------------------------------------------------------ + CPU-thread-0 {preempted} + CPU-thread-1 {} + CPU-thread-2 {} + CPU-thread-3 {} + DEV-thread-0 {read addrA from old page} + DEV-thread-2 {read addrB from new page} + +So here because at time N+2 the clear page table entry was not pair with a +notification to invalidate the secondary TLB, the device see the new value for +addrB before seing the new value for addrA. This break total memory ordering +for the device. + +When changing a pte to write protect or to point to a new write protected page +with same content (KSM) it is fine to delay the mmu_notifier_invalidate_range +call to mmu_notifier_invalidate_range_end() outside the page table lock. This +is true even if the thread doing the page table update is preempted right after +releasing page table lock but before call mmu_notifier_invalidate_range_end(). diff --git a/Documentation/vm/mmu_notifier.txt b/Documentation/vm/mmu_notifier.txt deleted file mode 100644 index 23b462566bb7..000000000000 --- a/Documentation/vm/mmu_notifier.txt +++ /dev/null @@ -1,93 +0,0 @@ -When do you need to notify inside page table lock ? - -When clearing a pte/pmd we are given a choice to notify the event through -(notify version of *_clear_flush call mmu_notifier_invalidate_range) under -the page table lock. But that notification is not necessary in all cases. - -For secondary TLB (non CPU TLB) like IOMMU TLB or device TLB (when device use -thing like ATS/PASID to get the IOMMU to walk the CPU page table to access a -process virtual address space). There is only 2 cases when you need to notify -those secondary TLB while holding page table lock when clearing a pte/pmd: - - A) page backing address is free before mmu_notifier_invalidate_range_end() - B) a page table entry is updated to point to a new page (COW, write fault - on zero page, __replace_page(), ...) - -Case A is obvious you do not want to take the risk for the device to write to -a page that might now be used by some completely different task. - -Case B is more subtle. For correctness it requires the following sequence to -happen: - - take page table lock - - clear page table entry and notify ([pmd/pte]p_huge_clear_flush_notify()) - - set page table entry to point to new page - -If clearing the page table entry is not followed by a notify before setting -the new pte/pmd value then you can break memory model like C11 or C++11 for -the device. - -Consider the following scenario (device use a feature similar to ATS/PASID): - -Two address addrA and addrB such that |addrA - addrB| >= PAGE_SIZE we assume -they are write protected for COW (other case of B apply too). - -[Time N] -------------------------------------------------------------------- -CPU-thread-0 {try to write to addrA} -CPU-thread-1 {try to write to addrB} -CPU-thread-2 {} -CPU-thread-3 {} -DEV-thread-0 {read addrA and populate device TLB} -DEV-thread-2 {read addrB and populate device TLB} -[Time N+1] ------------------------------------------------------------------ -CPU-thread-0 {COW_step0: {mmu_notifier_invalidate_range_start(addrA)}} -CPU-thread-1 {COW_step0: {mmu_notifier_invalidate_range_start(addrB)}} -CPU-thread-2 {} -CPU-thread-3 {} -DEV-thread-0 {} -DEV-thread-2 {} -[Time N+2] ------------------------------------------------------------------ -CPU-thread-0 {COW_step1: {update page table to point to new page for addrA}} -CPU-thread-1 {COW_step1: {update page table to point to new page for addrB}} -CPU-thread-2 {} -CPU-thread-3 {} -DEV-thread-0 {} -DEV-thread-2 {} -[Time N+3] ------------------------------------------------------------------ -CPU-thread-0 {preempted} -CPU-thread-1 {preempted} -CPU-thread-2 {write to addrA which is a write to new page} -CPU-thread-3 {} -DEV-thread-0 {} -DEV-thread-2 {} -[Time N+3] ------------------------------------------------------------------ -CPU-thread-0 {preempted} -CPU-thread-1 {preempted} -CPU-thread-2 {} -CPU-thread-3 {write to addrB which is a write to new page} -DEV-thread-0 {} -DEV-thread-2 {} -[Time N+4] ------------------------------------------------------------------ -CPU-thread-0 {preempted} -CPU-thread-1 {COW_step3: {mmu_notifier_invalidate_range_end(addrB)}} -CPU-thread-2 {} -CPU-thread-3 {} -DEV-thread-0 {} -DEV-thread-2 {} -[Time N+5] ------------------------------------------------------------------ -CPU-thread-0 {preempted} -CPU-thread-1 {} -CPU-thread-2 {} -CPU-thread-3 {} -DEV-thread-0 {read addrA from old page} -DEV-thread-2 {read addrB from new page} - -So here because at time N+2 the clear page table entry was not pair with a -notification to invalidate the secondary TLB, the device see the new value for -addrB before seing the new value for addrA. This break total memory ordering -for the device. - -When changing a pte to write protect or to point to a new write protected page -with same content (KSM) it is fine to delay the mmu_notifier_invalidate_range -call to mmu_notifier_invalidate_range_end() outside the page table lock. This -is true even if the thread doing the page table update is preempted right after -releasing page table lock but before call mmu_notifier_invalidate_range_end(). diff --git a/Documentation/vm/numa b/Documentation/vm/numa.rst index a31b85b9bb88..185d8a568168 100644 --- a/Documentation/vm/numa +++ b/Documentation/vm/numa.rst @@ -1,6 +1,10 @@ +.. _numa: + Started Nov 1999 by Kanoj Sarcar <kanoj@sgi.com> +============= What is NUMA? +============= This question can be answered from a couple of perspectives: the hardware view and the Linux software view. @@ -106,7 +110,7 @@ to improve NUMA locality using various CPU affinity command line interfaces, such as taskset(1) and numactl(1), and program interfaces such as sched_setaffinity(2). Further, one can modify the kernel's default local allocation behavior using Linux NUMA memory policy. -[see Documentation/vm/numa_memory_policy.txt.] +[see Documentation/admin-guide/mm/numa_memory_policy.rst.] System administrators can restrict the CPUs and nodes' memories that a non- privileged user can specify in the scheduling or NUMA commands and functions diff --git a/Documentation/vm/numa_memory_policy.txt b/Documentation/vm/numa_memory_policy.txt deleted file mode 100644 index 622b927816e7..000000000000 --- a/Documentation/vm/numa_memory_policy.txt +++ /dev/null @@ -1,452 +0,0 @@ - -What is Linux Memory Policy? - -In the Linux kernel, "memory policy" determines from which node the kernel will -allocate memory in a NUMA system or in an emulated NUMA system. Linux has -supported platforms with Non-Uniform Memory Access architectures since 2.4.?. -The current memory policy support was added to Linux 2.6 around May 2004. This -document attempts to describe the concepts and APIs of the 2.6 memory policy -support. - -Memory policies should not be confused with cpusets -(Documentation/cgroup-v1/cpusets.txt) -which is an administrative mechanism for restricting the nodes from which -memory may be allocated by a set of processes. Memory policies are a -programming interface that a NUMA-aware application can take advantage of. When -both cpusets and policies are applied to a task, the restrictions of the cpuset -takes priority. See "MEMORY POLICIES AND CPUSETS" below for more details. - -MEMORY POLICY CONCEPTS - -Scope of Memory Policies - -The Linux kernel supports _scopes_ of memory policy, described here from -most general to most specific: - - System Default Policy: this policy is "hard coded" into the kernel. It - is the policy that governs all page allocations that aren't controlled - by one of the more specific policy scopes discussed below. When the - system is "up and running", the system default policy will use "local - allocation" described below. However, during boot up, the system - default policy will be set to interleave allocations across all nodes - with "sufficient" memory, so as not to overload the initial boot node - with boot-time allocations. - - Task/Process Policy: this is an optional, per-task policy. When defined - for a specific task, this policy controls all page allocations made by or - on behalf of the task that aren't controlled by a more specific scope. - If a task does not define a task policy, then all page allocations that - would have been controlled by the task policy "fall back" to the System - Default Policy. - - The task policy applies to the entire address space of a task. Thus, - it is inheritable, and indeed is inherited, across both fork() - [clone() w/o the CLONE_VM flag] and exec*(). This allows a parent task - to establish the task policy for a child task exec()'d from an - executable image that has no awareness of memory policy. See the - MEMORY POLICY APIS section, below, for an overview of the system call - that a task may use to set/change its task/process policy. - - In a multi-threaded task, task policies apply only to the thread - [Linux kernel task] that installs the policy and any threads - subsequently created by that thread. Any sibling threads existing - at the time a new task policy is installed retain their current - policy. - - A task policy applies only to pages allocated after the policy is - installed. Any pages already faulted in by the task when the task - changes its task policy remain where they were allocated based on - the policy at the time they were allocated. - - VMA Policy: A "VMA" or "Virtual Memory Area" refers to a range of a task's - virtual address space. A task may define a specific policy for a range - of its virtual address space. See the MEMORY POLICIES APIS section, - below, for an overview of the mbind() system call used to set a VMA - policy. - - A VMA policy will govern the allocation of pages that back this region of - the address space. Any regions of the task's address space that don't - have an explicit VMA policy will fall back to the task policy, which may - itself fall back to the System Default Policy. - - VMA policies have a few complicating details: - - VMA policy applies ONLY to anonymous pages. These include pages - allocated for anonymous segments, such as the task stack and heap, and - any regions of the address space mmap()ed with the MAP_ANONYMOUS flag. - If a VMA policy is applied to a file mapping, it will be ignored if - the mapping used the MAP_SHARED flag. If the file mapping used the - MAP_PRIVATE flag, the VMA policy will only be applied when an - anonymous page is allocated on an attempt to write to the mapping-- - i.e., at Copy-On-Write. - - VMA policies are shared between all tasks that share a virtual address - space--a.k.a. threads--independent of when the policy is installed; and - they are inherited across fork(). However, because VMA policies refer - to a specific region of a task's address space, and because the address - space is discarded and recreated on exec*(), VMA policies are NOT - inheritable across exec(). Thus, only NUMA-aware applications may - use VMA policies. - - A task may install a new VMA policy on a sub-range of a previously - mmap()ed region. When this happens, Linux splits the existing virtual - memory area into 2 or 3 VMAs, each with it's own policy. - - By default, VMA policy applies only to pages allocated after the policy - is installed. Any pages already faulted into the VMA range remain - where they were allocated based on the policy at the time they were - allocated. However, since 2.6.16, Linux supports page migration via - the mbind() system call, so that page contents can be moved to match - a newly installed policy. - - Shared Policy: Conceptually, shared policies apply to "memory objects" - mapped shared into one or more tasks' distinct address spaces. An - application installs a shared policies the same way as VMA policies--using - the mbind() system call specifying a range of virtual addresses that map - the shared object. However, unlike VMA policies, which can be considered - to be an attribute of a range of a task's address space, shared policies - apply directly to the shared object. Thus, all tasks that attach to the - object share the policy, and all pages allocated for the shared object, - by any task, will obey the shared policy. - - As of 2.6.22, only shared memory segments, created by shmget() or - mmap(MAP_ANONYMOUS|MAP_SHARED), support shared policy. When shared - policy support was added to Linux, the associated data structures were - added to hugetlbfs shmem segments. At the time, hugetlbfs did not - support allocation at fault time--a.k.a lazy allocation--so hugetlbfs - shmem segments were never "hooked up" to the shared policy support. - Although hugetlbfs segments now support lazy allocation, their support - for shared policy has not been completed. - - As mentioned above [re: VMA policies], allocations of page cache - pages for regular files mmap()ed with MAP_SHARED ignore any VMA - policy installed on the virtual address range backed by the shared - file mapping. Rather, shared page cache pages, including pages backing - private mappings that have not yet been written by the task, follow - task policy, if any, else System Default Policy. - - The shared policy infrastructure supports different policies on subset - ranges of the shared object. However, Linux still splits the VMA of - the task that installs the policy for each range of distinct policy. - Thus, different tasks that attach to a shared memory segment can have - different VMA configurations mapping that one shared object. This - can be seen by examining the /proc/<pid>/numa_maps of tasks sharing - a shared memory region, when one task has installed shared policy on - one or more ranges of the region. - -Components of Memory Policies - - A Linux memory policy consists of a "mode", optional mode flags, and an - optional set of nodes. The mode determines the behavior of the policy, - the optional mode flags determine the behavior of the mode, and the - optional set of nodes can be viewed as the arguments to the policy - behavior. - - Internally, memory policies are implemented by a reference counted - structure, struct mempolicy. Details of this structure will be discussed - in context, below, as required to explain the behavior. - - Linux memory policy supports the following 4 behavioral modes: - - Default Mode--MPOL_DEFAULT: This mode is only used in the memory - policy APIs. Internally, MPOL_DEFAULT is converted to the NULL - memory policy in all policy scopes. Any existing non-default policy - will simply be removed when MPOL_DEFAULT is specified. As a result, - MPOL_DEFAULT means "fall back to the next most specific policy scope." - - For example, a NULL or default task policy will fall back to the - system default policy. A NULL or default vma policy will fall - back to the task policy. - - When specified in one of the memory policy APIs, the Default mode - does not use the optional set of nodes. - - It is an error for the set of nodes specified for this policy to - be non-empty. - - MPOL_BIND: This mode specifies that memory must come from the - set of nodes specified by the policy. Memory will be allocated from - the node in the set with sufficient free memory that is closest to - the node where the allocation takes place. - - MPOL_PREFERRED: This mode specifies that the allocation should be - attempted from the single node specified in the policy. If that - allocation fails, the kernel will search other nodes, in order of - increasing distance from the preferred node based on information - provided by the platform firmware. - - Internally, the Preferred policy uses a single node--the - preferred_node member of struct mempolicy. When the internal - mode flag MPOL_F_LOCAL is set, the preferred_node is ignored and - the policy is interpreted as local allocation. "Local" allocation - policy can be viewed as a Preferred policy that starts at the node - containing the cpu where the allocation takes place. - - It is possible for the user to specify that local allocation is - always preferred by passing an empty nodemask with this mode. - If an empty nodemask is passed, the policy cannot use the - MPOL_F_STATIC_NODES or MPOL_F_RELATIVE_NODES flags described - below. - - MPOL_INTERLEAVED: This mode specifies that page allocations be - interleaved, on a page granularity, across the nodes specified in - the policy. This mode also behaves slightly differently, based on - the context where it is used: - - For allocation of anonymous pages and shared memory pages, - Interleave mode indexes the set of nodes specified by the policy - using the page offset of the faulting address into the segment - [VMA] containing the address modulo the number of nodes specified - by the policy. It then attempts to allocate a page, starting at - the selected node, as if the node had been specified by a Preferred - policy or had been selected by a local allocation. That is, - allocation will follow the per node zonelist. - - For allocation of page cache pages, Interleave mode indexes the set - of nodes specified by the policy using a node counter maintained - per task. This counter wraps around to the lowest specified node - after it reaches the highest specified node. This will tend to - spread the pages out over the nodes specified by the policy based - on the order in which they are allocated, rather than based on any - page offset into an address range or file. During system boot up, - the temporary interleaved system default policy works in this - mode. - - Linux memory policy supports the following optional mode flags: - - MPOL_F_STATIC_NODES: This flag specifies that the nodemask passed by - the user should not be remapped if the task or VMA's set of allowed - nodes changes after the memory policy has been defined. - - Without this flag, anytime a mempolicy is rebound because of a - change in the set of allowed nodes, the node (Preferred) or - nodemask (Bind, Interleave) is remapped to the new set of - allowed nodes. This may result in nodes being used that were - previously undesired. - - With this flag, if the user-specified nodes overlap with the - nodes allowed by the task's cpuset, then the memory policy is - applied to their intersection. If the two sets of nodes do not - overlap, the Default policy is used. - - For example, consider a task that is attached to a cpuset with - mems 1-3 that sets an Interleave policy over the same set. If - the cpuset's mems change to 3-5, the Interleave will now occur - over nodes 3, 4, and 5. With this flag, however, since only node - 3 is allowed from the user's nodemask, the "interleave" only - occurs over that node. If no nodes from the user's nodemask are - now allowed, the Default behavior is used. - - MPOL_F_STATIC_NODES cannot be combined with the - MPOL_F_RELATIVE_NODES flag. It also cannot be used for - MPOL_PREFERRED policies that were created with an empty nodemask - (local allocation). - - MPOL_F_RELATIVE_NODES: This flag specifies that the nodemask passed - by the user will be mapped relative to the set of the task or VMA's - set of allowed nodes. The kernel stores the user-passed nodemask, - and if the allowed nodes changes, then that original nodemask will - be remapped relative to the new set of allowed nodes. - - Without this flag (and without MPOL_F_STATIC_NODES), anytime a - mempolicy is rebound because of a change in the set of allowed - nodes, the node (Preferred) or nodemask (Bind, Interleave) is - remapped to the new set of allowed nodes. That remap may not - preserve the relative nature of the user's passed nodemask to its - set of allowed nodes upon successive rebinds: a nodemask of - 1,3,5 may be remapped to 7-9 and then to 1-3 if the set of - allowed nodes is restored to its original state. - - With this flag, the remap is done so that the node numbers from - the user's passed nodemask are relative to the set of allowed - nodes. In other words, if nodes 0, 2, and 4 are set in the user's - nodemask, the policy will be effected over the first (and in the - Bind or Interleave case, the third and fifth) nodes in the set of - allowed nodes. The nodemask passed by the user represents nodes - relative to task or VMA's set of allowed nodes. - - If the user's nodemask includes nodes that are outside the range - of the new set of allowed nodes (for example, node 5 is set in - the user's nodemask when the set of allowed nodes is only 0-3), - then the remap wraps around to the beginning of the nodemask and, - if not already set, sets the node in the mempolicy nodemask. - - For example, consider a task that is attached to a cpuset with - mems 2-5 that sets an Interleave policy over the same set with - MPOL_F_RELATIVE_NODES. If the cpuset's mems change to 3-7, the - interleave now occurs over nodes 3,5-7. If the cpuset's mems - then change to 0,2-3,5, then the interleave occurs over nodes - 0,2-3,5. - - Thanks to the consistent remapping, applications preparing - nodemasks to specify memory policies using this flag should - disregard their current, actual cpuset imposed memory placement - and prepare the nodemask as if they were always located on - memory nodes 0 to N-1, where N is the number of memory nodes the - policy is intended to manage. Let the kernel then remap to the - set of memory nodes allowed by the task's cpuset, as that may - change over time. - - MPOL_F_RELATIVE_NODES cannot be combined with the - MPOL_F_STATIC_NODES flag. It also cannot be used for - MPOL_PREFERRED policies that were created with an empty nodemask - (local allocation). - -MEMORY POLICY REFERENCE COUNTING - -To resolve use/free races, struct mempolicy contains an atomic reference -count field. Internal interfaces, mpol_get()/mpol_put() increment and -decrement this reference count, respectively. mpol_put() will only free -the structure back to the mempolicy kmem cache when the reference count -goes to zero. - -When a new memory policy is allocated, its reference count is initialized -to '1', representing the reference held by the task that is installing the -new policy. When a pointer to a memory policy structure is stored in another -structure, another reference is added, as the task's reference will be dropped -on completion of the policy installation. - -During run-time "usage" of the policy, we attempt to minimize atomic operations -on the reference count, as this can lead to cache lines bouncing between cpus -and NUMA nodes. "Usage" here means one of the following: - -1) querying of the policy, either by the task itself [using the get_mempolicy() - API discussed below] or by another task using the /proc/<pid>/numa_maps - interface. - -2) examination of the policy to determine the policy mode and associated node - or node lists, if any, for page allocation. This is considered a "hot - path". Note that for MPOL_BIND, the "usage" extends across the entire - allocation process, which may sleep during page reclaimation, because the - BIND policy nodemask is used, by reference, to filter ineligible nodes. - -We can avoid taking an extra reference during the usages listed above as -follows: - -1) we never need to get/free the system default policy as this is never - changed nor freed, once the system is up and running. - -2) for querying the policy, we do not need to take an extra reference on the - target task's task policy nor vma policies because we always acquire the - task's mm's mmap_sem for read during the query. The set_mempolicy() and - mbind() APIs [see below] always acquire the mmap_sem for write when - installing or replacing task or vma policies. Thus, there is no possibility - of a task or thread freeing a policy while another task or thread is - querying it. - -3) Page allocation usage of task or vma policy occurs in the fault path where - we hold them mmap_sem for read. Again, because replacing the task or vma - policy requires that the mmap_sem be held for write, the policy can't be - freed out from under us while we're using it for page allocation. - -4) Shared policies require special consideration. One task can replace a - shared memory policy while another task, with a distinct mmap_sem, is - querying or allocating a page based on the policy. To resolve this - potential race, the shared policy infrastructure adds an extra reference - to the shared policy during lookup while holding a spin lock on the shared - policy management structure. This requires that we drop this extra - reference when we're finished "using" the policy. We must drop the - extra reference on shared policies in the same query/allocation paths - used for non-shared policies. For this reason, shared policies are marked - as such, and the extra reference is dropped "conditionally"--i.e., only - for shared policies. - - Because of this extra reference counting, and because we must lookup - shared policies in a tree structure under spinlock, shared policies are - more expensive to use in the page allocation path. This is especially - true for shared policies on shared memory regions shared by tasks running - on different NUMA nodes. This extra overhead can be avoided by always - falling back to task or system default policy for shared memory regions, - or by prefaulting the entire shared memory region into memory and locking - it down. However, this might not be appropriate for all applications. - -MEMORY POLICY APIs - -Linux supports 3 system calls for controlling memory policy. These APIS -always affect only the calling task, the calling task's address space, or -some shared object mapped into the calling task's address space. - - Note: the headers that define these APIs and the parameter data types - for user space applications reside in a package that is not part of - the Linux kernel. The kernel system call interfaces, with the 'sys_' - prefix, are defined in <linux/syscalls.h>; the mode and flag - definitions are defined in <linux/mempolicy.h>. - -Set [Task] Memory Policy: - - long set_mempolicy(int mode, const unsigned long *nmask, - unsigned long maxnode); - - Set's the calling task's "task/process memory policy" to mode - specified by the 'mode' argument and the set of nodes defined - by 'nmask'. 'nmask' points to a bit mask of node ids containing - at least 'maxnode' ids. Optional mode flags may be passed by - combining the 'mode' argument with the flag (for example: - MPOL_INTERLEAVE | MPOL_F_STATIC_NODES). - - See the set_mempolicy(2) man page for more details - - -Get [Task] Memory Policy or Related Information - - long get_mempolicy(int *mode, - const unsigned long *nmask, unsigned long maxnode, - void *addr, int flags); - - Queries the "task/process memory policy" of the calling task, or - the policy or location of a specified virtual address, depending - on the 'flags' argument. - - See the get_mempolicy(2) man page for more details - - -Install VMA/Shared Policy for a Range of Task's Address Space - - long mbind(void *start, unsigned long len, int mode, - const unsigned long *nmask, unsigned long maxnode, - unsigned flags); - - mbind() installs the policy specified by (mode, nmask, maxnodes) as - a VMA policy for the range of the calling task's address space - specified by the 'start' and 'len' arguments. Additional actions - may be requested via the 'flags' argument. - - See the mbind(2) man page for more details. - -MEMORY POLICY COMMAND LINE INTERFACE - -Although not strictly part of the Linux implementation of memory policy, -a command line tool, numactl(8), exists that allows one to: - -+ set the task policy for a specified program via set_mempolicy(2), fork(2) and - exec(2) - -+ set the shared policy for a shared memory segment via mbind(2) - -The numactl(8) tool is packaged with the run-time version of the library -containing the memory policy system call wrappers. Some distributions -package the headers and compile-time libraries in a separate development -package. - - -MEMORY POLICIES AND CPUSETS - -Memory policies work within cpusets as described above. For memory policies -that require a node or set of nodes, the nodes are restricted to the set of -nodes whose memories are allowed by the cpuset constraints. If the nodemask -specified for the policy contains nodes that are not allowed by the cpuset and -MPOL_F_RELATIVE_NODES is not used, the intersection of the set of nodes -specified for the policy and the set of nodes with memory is used. If the -result is the empty set, the policy is considered invalid and cannot be -installed. If MPOL_F_RELATIVE_NODES is used, the policy's nodes are mapped -onto and folded into the task's set of allowed nodes as previously described. - -The interaction of memory policies and cpusets can be problematic when tasks -in two cpusets share access to a memory region, such as shared memory segments -created by shmget() of mmap() with the MAP_ANONYMOUS and MAP_SHARED flags, and -any of the tasks install shared policy on the region, only nodes whose -memories are allowed in both cpusets may be used in the policies. Obtaining -this information requires "stepping outside" the memory policy APIs to use the -cpuset information and requires that one know in what cpusets other task might -be attaching to the shared region. Furthermore, if the cpusets' allowed -memory sets are disjoint, "local" allocation is the only valid policy. diff --git a/Documentation/vm/overcommit-accounting b/Documentation/vm/overcommit-accounting deleted file mode 100644 index cbfaaa674118..000000000000 --- a/Documentation/vm/overcommit-accounting +++ /dev/null @@ -1,80 +0,0 @@ -The Linux kernel supports the following overcommit handling modes - -0 - Heuristic overcommit handling. Obvious overcommits of - address space are refused. Used for a typical system. It - ensures a seriously wild allocation fails while allowing - overcommit to reduce swap usage. root is allowed to - allocate slightly more memory in this mode. This is the - default. - -1 - Always overcommit. Appropriate for some scientific - applications. Classic example is code using sparse arrays - and just relying on the virtual memory consisting almost - entirely of zero pages. - -2 - Don't overcommit. The total address space commit - for the system is not permitted to exceed swap + a - configurable amount (default is 50%) of physical RAM. - Depending on the amount you use, in most situations - this means a process will not be killed while accessing - pages but will receive errors on memory allocation as - appropriate. - - Useful for applications that want to guarantee their - memory allocations will be available in the future - without having to initialize every page. - -The overcommit policy is set via the sysctl `vm.overcommit_memory'. - -The overcommit amount can be set via `vm.overcommit_ratio' (percentage) -or `vm.overcommit_kbytes' (absolute value). - -The current overcommit limit and amount committed are viewable in -/proc/meminfo as CommitLimit and Committed_AS respectively. - -Gotchas -------- - -The C language stack growth does an implicit mremap. If you want absolute -guarantees and run close to the edge you MUST mmap your stack for the -largest size you think you will need. For typical stack usage this does -not matter much but it's a corner case if you really really care - -In mode 2 the MAP_NORESERVE flag is ignored. - - -How It Works ------------- - -The overcommit is based on the following rules - -For a file backed map - SHARED or READ-only - 0 cost (the file is the map not swap) - PRIVATE WRITABLE - size of mapping per instance - -For an anonymous or /dev/zero map - SHARED - size of mapping - PRIVATE READ-only - 0 cost (but of little use) - PRIVATE WRITABLE - size of mapping per instance - -Additional accounting - Pages made writable copies by mmap - shmfs memory drawn from the same pool - -Status ------- - -o We account mmap memory mappings -o We account mprotect changes in commit -o We account mremap changes in size -o We account brk -o We account munmap -o We report the commit status in /proc -o Account and check on fork -o Review stack handling/building on exec -o SHMfs accounting -o Implement actual limit enforcement - -To Do ------ -o Account ptrace pages (this is hard) diff --git a/Documentation/vm/overcommit-accounting.rst b/Documentation/vm/overcommit-accounting.rst new file mode 100644 index 000000000000..0dd54bbe4afa --- /dev/null +++ b/Documentation/vm/overcommit-accounting.rst @@ -0,0 +1,87 @@ +.. _overcommit_accounting: + +===================== +Overcommit Accounting +===================== + +The Linux kernel supports the following overcommit handling modes + +0 + Heuristic overcommit handling. Obvious overcommits of address + space are refused. Used for a typical system. It ensures a + seriously wild allocation fails while allowing overcommit to + reduce swap usage. root is allowed to allocate slightly more + memory in this mode. This is the default. + +1 + Always overcommit. Appropriate for some scientific + applications. Classic example is code using sparse arrays and + just relying on the virtual memory consisting almost entirely + of zero pages. + +2 + Don't overcommit. The total address space commit for the + system is not permitted to exceed swap + a configurable amount + (default is 50%) of physical RAM. Depending on the amount you + use, in most situations this means a process will not be + killed while accessing pages but will receive errors on memory + allocation as appropriate. + + Useful for applications that want to guarantee their memory + allocations will be available in the future without having to + initialize every page. + +The overcommit policy is set via the sysctl ``vm.overcommit_memory``. + +The overcommit amount can be set via ``vm.overcommit_ratio`` (percentage) +or ``vm.overcommit_kbytes`` (absolute value). + +The current overcommit limit and amount committed are viewable in +``/proc/meminfo`` as CommitLimit and Committed_AS respectively. + +Gotchas +======= + +The C language stack growth does an implicit mremap. If you want absolute +guarantees and run close to the edge you MUST mmap your stack for the +largest size you think you will need. For typical stack usage this does +not matter much but it's a corner case if you really really care + +In mode 2 the MAP_NORESERVE flag is ignored. + + +How It Works +============ + +The overcommit is based on the following rules + +For a file backed map + | SHARED or READ-only - 0 cost (the file is the map not swap) + | PRIVATE WRITABLE - size of mapping per instance + +For an anonymous or ``/dev/zero`` map + | SHARED - size of mapping + | PRIVATE READ-only - 0 cost (but of little use) + | PRIVATE WRITABLE - size of mapping per instance + +Additional accounting + | Pages made writable copies by mmap + | shmfs memory drawn from the same pool + +Status +====== + +* We account mmap memory mappings +* We account mprotect changes in commit +* We account mremap changes in size +* We account brk +* We account munmap +* We report the commit status in /proc +* Account and check on fork +* Review stack handling/building on exec +* SHMfs accounting +* Implement actual limit enforcement + +To Do +===== +* Account ptrace pages (this is hard) diff --git a/Documentation/vm/page_frags b/Documentation/vm/page_frags.rst index a6714565dbf9..637cc49d1b2f 100644 --- a/Documentation/vm/page_frags +++ b/Documentation/vm/page_frags.rst @@ -1,5 +1,8 @@ +.. _page_frags: + +============== Page fragments --------------- +============== A page fragment is an arbitrary-length arbitrary-offset area of memory which resides within a 0 or higher order compound page. Multiple diff --git a/Documentation/vm/page_migration b/Documentation/vm/page_migration.rst index 0478ae2ad44a..f68d61335abb 100644 --- a/Documentation/vm/page_migration +++ b/Documentation/vm/page_migration.rst @@ -1,5 +1,8 @@ +.. _page_migration: + +============== Page migration --------------- +============== Page migration allows the moving of the physical location of pages between nodes in a numa system while the process is running. This means that the @@ -20,7 +23,7 @@ Page migration functions are provided by the numactl package by Andi Kleen (a version later than 0.9.3 is required. Get it from ftp://oss.sgi.com/www/projects/libnuma/download/). numactl provides libnuma which provides an interface similar to other numa functionality for page -migration. cat /proc/<pid>/numa_maps allows an easy review of where the +migration. cat ``/proc/<pid>/numa_maps`` allows an easy review of where the pages of a process are located. See also the numa_maps documentation in the proc(5) man page. @@ -56,8 +59,8 @@ description for those trying to use migrate_pages() from the kernel (for userspace usage see the Andi Kleen's numactl package mentioned above) and then a low level description of how the low level details work. -A. In kernel use of migrate_pages() ------------------------------------ +In kernel use of migrate_pages() +================================ 1. Remove pages from the LRU. @@ -78,8 +81,8 @@ A. In kernel use of migrate_pages() the new page for each page that is considered for moving. -B. How migrate_pages() works ----------------------------- +How migrate_pages() works +========================= migrate_pages() does several passes over its list of pages. A page is moved if all references to a page are removable at the time. The page has @@ -90,7 +93,7 @@ Steps: 1. Lock the page to be migrated -2. Insure that writeback is complete. +2. Ensure that writeback is complete. 3. Lock the new page that we want to move to. It is locked so that accesses to this (not yet uptodate) page immediately lock while the move is in progress. @@ -100,8 +103,8 @@ Steps: mapcount is not zero then we do not migrate the page. All user space processes that attempt to access the page will now wait on the page lock. -5. The radix tree lock is taken. This will cause all processes trying - to access the page via the mapping to block on the radix tree spinlock. +5. The i_pages lock is taken. This will cause all processes trying + to access the page via the mapping to block on the spinlock. 6. The refcount of the page is examined and we back out if references remain otherwise we know that we are the only one referencing this page. @@ -114,12 +117,12 @@ Steps: 9. The radix tree is changed to point to the new page. -10. The reference count of the old page is dropped because the radix tree +10. The reference count of the old page is dropped because the address space reference is gone. A reference to the new page is established because - the new page is referenced to by the radix tree. + the new page is referenced by the address space. -11. The radix tree lock is dropped. With that lookups in the mapping - become possible again. Processes will move from spinning on the tree_lock +11. The i_pages lock is dropped. With that lookups in the mapping + become possible again. Processes will move from spinning on the lock to sleeping on the locked new page. 12. The page contents are copied to the new page. @@ -142,8 +145,8 @@ Steps: 20. The new page is moved to the LRU and can be scanned by the swapper etc again. -C. Non-LRU page migration -------------------------- +Non-LRU page migration +====================== Although original migration aimed for reducing the latency of memory access for NUMA, compaction who want to create high-order page is also main customer. @@ -164,89 +167,91 @@ migration path. If a driver want to make own pages movable, it should define three functions which are function pointers of struct address_space_operations. -1. bool (*isolate_page) (struct page *page, isolate_mode_t mode); +1. ``bool (*isolate_page) (struct page *page, isolate_mode_t mode);`` -What VM expects on isolate_page function of driver is to return *true* -if driver isolates page successfully. On returing true, VM marks the page -as PG_isolated so concurrent isolation in several CPUs skip the page -for isolation. If a driver cannot isolate the page, it should return *false*. + What VM expects on isolate_page function of driver is to return *true* + if driver isolates page successfully. On returing true, VM marks the page + as PG_isolated so concurrent isolation in several CPUs skip the page + for isolation. If a driver cannot isolate the page, it should return *false*. -Once page is successfully isolated, VM uses page.lru fields so driver -shouldn't expect to preserve values in that fields. + Once page is successfully isolated, VM uses page.lru fields so driver + shouldn't expect to preserve values in that fields. -2. int (*migratepage) (struct address_space *mapping, - struct page *newpage, struct page *oldpage, enum migrate_mode); +2. ``int (*migratepage) (struct address_space *mapping,`` +| ``struct page *newpage, struct page *oldpage, enum migrate_mode);`` -After isolation, VM calls migratepage of driver with isolated page. -The function of migratepage is to move content of the old page to new page -and set up fields of struct page newpage. Keep in mind that you should -indicate to the VM the oldpage is no longer movable via __ClearPageMovable() -under page_lock if you migrated the oldpage successfully and returns -MIGRATEPAGE_SUCCESS. If driver cannot migrate the page at the moment, driver -can return -EAGAIN. On -EAGAIN, VM will retry page migration in a short time -because VM interprets -EAGAIN as "temporal migration failure". On returning -any error except -EAGAIN, VM will give up the page migration without retrying -in this time. + After isolation, VM calls migratepage of driver with isolated page. + The function of migratepage is to move content of the old page to new page + and set up fields of struct page newpage. Keep in mind that you should + indicate to the VM the oldpage is no longer movable via __ClearPageMovable() + under page_lock if you migrated the oldpage successfully and returns + MIGRATEPAGE_SUCCESS. If driver cannot migrate the page at the moment, driver + can return -EAGAIN. On -EAGAIN, VM will retry page migration in a short time + because VM interprets -EAGAIN as "temporal migration failure". On returning + any error except -EAGAIN, VM will give up the page migration without retrying + in this time. -Driver shouldn't touch page.lru field VM using in the functions. + Driver shouldn't touch page.lru field VM using in the functions. -3. void (*putback_page)(struct page *); +3. ``void (*putback_page)(struct page *);`` -If migration fails on isolated page, VM should return the isolated page -to the driver so VM calls driver's putback_page with migration failed page. -In this function, driver should put the isolated page back to the own data -structure. + If migration fails on isolated page, VM should return the isolated page + to the driver so VM calls driver's putback_page with migration failed page. + In this function, driver should put the isolated page back to the own data + structure. 4. non-lru movable page flags -There are two page flags for supporting non-lru movable page. + There are two page flags for supporting non-lru movable page. -* PG_movable + * PG_movable -Driver should use the below function to make page movable under page_lock. + Driver should use the below function to make page movable under page_lock:: void __SetPageMovable(struct page *page, struct address_space *mapping) -It needs argument of address_space for registering migration family functions -which will be called by VM. Exactly speaking, PG_movable is not a real flag of -struct page. Rather than, VM reuses page->mapping's lower bits to represent it. + It needs argument of address_space for registering migration + family functions which will be called by VM. Exactly speaking, + PG_movable is not a real flag of struct page. Rather than, VM + reuses page->mapping's lower bits to represent it. +:: #define PAGE_MAPPING_MOVABLE 0x2 page->mapping = page->mapping | PAGE_MAPPING_MOVABLE; -so driver shouldn't access page->mapping directly. Instead, driver should -use page_mapping which mask off the low two bits of page->mapping under -page lock so it can get right struct address_space. - -For testing of non-lru movable page, VM supports __PageMovable function. -However, it doesn't guarantee to identify non-lru movable page because -page->mapping field is unified with other variables in struct page. -As well, if driver releases the page after isolation by VM, page->mapping -doesn't have stable value although it has PAGE_MAPPING_MOVABLE -(Look at __ClearPageMovable). But __PageMovable is cheap to catch whether -page is LRU or non-lru movable once the page has been isolated. Because -LRU pages never can have PAGE_MAPPING_MOVABLE in page->mapping. It is also -good for just peeking to test non-lru movable pages before more expensive -checking with lock_page in pfn scanning to select victim. - -For guaranteeing non-lru movable page, VM provides PageMovable function. -Unlike __PageMovable, PageMovable functions validates page->mapping and -mapping->a_ops->isolate_page under lock_page. The lock_page prevents sudden -destroying of page->mapping. - -Driver using __SetPageMovable should clear the flag via __ClearMovablePage -under page_lock before the releasing the page. - -* PG_isolated - -To prevent concurrent isolation among several CPUs, VM marks isolated page -as PG_isolated under lock_page. So if a CPU encounters PG_isolated non-lru -movable page, it can skip it. Driver doesn't need to manipulate the flag -because VM will set/clear it automatically. Keep in mind that if driver -sees PG_isolated page, it means the page have been isolated by VM so it -shouldn't touch page.lru field. -PG_isolated is alias with PG_reclaim flag so driver shouldn't use the flag -for own purpose. + so driver shouldn't access page->mapping directly. Instead, driver should + use page_mapping which mask off the low two bits of page->mapping under + page lock so it can get right struct address_space. + + For testing of non-lru movable page, VM supports __PageMovable function. + However, it doesn't guarantee to identify non-lru movable page because + page->mapping field is unified with other variables in struct page. + As well, if driver releases the page after isolation by VM, page->mapping + doesn't have stable value although it has PAGE_MAPPING_MOVABLE + (Look at __ClearPageMovable). But __PageMovable is cheap to catch whether + page is LRU or non-lru movable once the page has been isolated. Because + LRU pages never can have PAGE_MAPPING_MOVABLE in page->mapping. It is also + good for just peeking to test non-lru movable pages before more expensive + checking with lock_page in pfn scanning to select victim. + + For guaranteeing non-lru movable page, VM provides PageMovable function. + Unlike __PageMovable, PageMovable functions validates page->mapping and + mapping->a_ops->isolate_page under lock_page. The lock_page prevents sudden + destroying of page->mapping. + + Driver using __SetPageMovable should clear the flag via __ClearMovablePage + under page_lock before the releasing the page. + + * PG_isolated + + To prevent concurrent isolation among several CPUs, VM marks isolated page + as PG_isolated under lock_page. So if a CPU encounters PG_isolated non-lru + movable page, it can skip it. Driver doesn't need to manipulate the flag + because VM will set/clear it automatically. Keep in mind that if driver + sees PG_isolated page, it means the page have been isolated by VM so it + shouldn't touch page.lru field. + PG_isolated is alias with PG_reclaim flag so driver shouldn't use the flag + for own purpose. Christoph Lameter, May 8, 2006. Minchan Kim, Mar 28, 2016. diff --git a/Documentation/vm/page_owner.txt b/Documentation/vm/page_owner.rst index ffff1439076a..0ed5ab8c7ab4 100644 --- a/Documentation/vm/page_owner.txt +++ b/Documentation/vm/page_owner.rst @@ -1,7 +1,11 @@ +.. _page_owner: + +================================================== page owner: Tracking about who allocated each page ------------------------------------------------------------ +================================================== -* Introduction +Introduction +============ page owner is for the tracking about who allocated each page. It can be used to debug memory leak or to find a memory hogger. @@ -34,13 +38,15 @@ not affect to allocation performance, especially if the static keys jump label patching functionality is available. Following is the kernel's code size change due to this facility. -- Without page owner +- Without page owner:: + text data bss dec hex filename - 40662 1493 644 42799 a72f mm/page_alloc.o + 40662 1493 644 42799 a72f mm/page_alloc.o + +- With page owner:: -- With page owner text data bss dec hex filename - 40892 1493 644 43029 a815 mm/page_alloc.o + 40892 1493 644 43029 a815 mm/page_alloc.o 1427 24 8 1459 5b3 mm/page_ext.o 2722 50 0 2772 ad4 mm/page_owner.o @@ -62,21 +68,23 @@ are catched and marked, although they are mostly allocated from struct page extension feature. Anyway, after that, no page is left in un-tracking state. -* Usage +Usage +===== + +1) Build user-space helper:: -1) Build user-space helper cd tools/vm make page_owner_sort -2) Enable page owner - Add "page_owner=on" to boot cmdline. +2) Enable page owner: add "page_owner=on" to boot cmdline. 3) Do the job what you want to debug -4) Analyze information from page owner +4) Analyze information from page owner:: + cat /sys/kernel/debug/page_owner > page_owner_full.txt grep -v ^PFN page_owner_full.txt > page_owner.txt ./page_owner_sort page_owner.txt sorted_page_owner.txt - See the result about who allocated each page - in the sorted_page_owner.txt. + See the result about who allocated each page + in the ``sorted_page_owner.txt``. diff --git a/Documentation/vm/remap_file_pages.txt b/Documentation/vm/remap_file_pages.rst index f609142f406a..7bef6718e3a9 100644 --- a/Documentation/vm/remap_file_pages.txt +++ b/Documentation/vm/remap_file_pages.rst @@ -1,3 +1,9 @@ +.. _remap_file_pages: + +============================== +remap_file_pages() system call +============================== + The remap_file_pages() system call is used to create a nonlinear mapping, that is, a mapping in which the pages of the file are mapped into a nonsequential order in memory. The advantage of using remap_file_pages() diff --git a/Documentation/vm/slub.rst b/Documentation/vm/slub.rst new file mode 100644 index 000000000000..3a775fd64e2d --- /dev/null +++ b/Documentation/vm/slub.rst @@ -0,0 +1,361 @@ +.. _slub: + +========================== +Short users guide for SLUB +========================== + +The basic philosophy of SLUB is very different from SLAB. SLAB +requires rebuilding the kernel to activate debug options for all +slab caches. SLUB always includes full debugging but it is off by default. +SLUB can enable debugging only for selected slabs in order to avoid +an impact on overall system performance which may make a bug more +difficult to find. + +In order to switch debugging on one can add an option ``slub_debug`` +to the kernel command line. That will enable full debugging for +all slabs. + +Typically one would then use the ``slabinfo`` command to get statistical +data and perform operation on the slabs. By default ``slabinfo`` only lists +slabs that have data in them. See "slabinfo -h" for more options when +running the command. ``slabinfo`` can be compiled with +:: + + gcc -o slabinfo tools/vm/slabinfo.c + +Some of the modes of operation of ``slabinfo`` require that slub debugging +be enabled on the command line. F.e. no tracking information will be +available without debugging on and validation can only partially +be performed if debugging was not switched on. + +Some more sophisticated uses of slub_debug: +------------------------------------------- + +Parameters may be given to ``slub_debug``. If none is specified then full +debugging is enabled. Format: + +slub_debug=<Debug-Options> + Enable options for all slabs +slub_debug=<Debug-Options>,<slab name> + Enable options only for select slabs + + +Possible debug options are:: + + F Sanity checks on (enables SLAB_DEBUG_CONSISTENCY_CHECKS + Sorry SLAB legacy issues) + Z Red zoning + P Poisoning (object and padding) + U User tracking (free and alloc) + T Trace (please only use on single slabs) + A Toggle failslab filter mark for the cache + O Switch debugging off for caches that would have + caused higher minimum slab orders + - Switch all debugging off (useful if the kernel is + configured with CONFIG_SLUB_DEBUG_ON) + +F.e. in order to boot just with sanity checks and red zoning one would specify:: + + slub_debug=FZ + +Trying to find an issue in the dentry cache? Try:: + + slub_debug=,dentry + +to only enable debugging on the dentry cache. + +Red zoning and tracking may realign the slab. We can just apply sanity checks +to the dentry cache with:: + + slub_debug=F,dentry + +Debugging options may require the minimum possible slab order to increase as +a result of storing the metadata (for example, caches with PAGE_SIZE object +sizes). This has a higher liklihood of resulting in slab allocation errors +in low memory situations or if there's high fragmentation of memory. To +switch off debugging for such caches by default, use:: + + slub_debug=O + +In case you forgot to enable debugging on the kernel command line: It is +possible to enable debugging manually when the kernel is up. Look at the +contents of:: + + /sys/kernel/slab/<slab name>/ + +Look at the writable files. Writing 1 to them will enable the +corresponding debug option. All options can be set on a slab that does +not contain objects. If the slab already contains objects then sanity checks +and tracing may only be enabled. The other options may cause the realignment +of objects. + +Careful with tracing: It may spew out lots of information and never stop if +used on the wrong slab. + +Slab merging +============ + +If no debug options are specified then SLUB may merge similar slabs together +in order to reduce overhead and increase cache hotness of objects. +``slabinfo -a`` displays which slabs were merged together. + +Slab validation +=============== + +SLUB can validate all object if the kernel was booted with slub_debug. In +order to do so you must have the ``slabinfo`` tool. Then you can do +:: + + slabinfo -v + +which will test all objects. Output will be generated to the syslog. + +This also works in a more limited way if boot was without slab debug. +In that case ``slabinfo -v`` simply tests all reachable objects. Usually +these are in the cpu slabs and the partial slabs. Full slabs are not +tracked by SLUB in a non debug situation. + +Getting more performance +======================== + +To some degree SLUB's performance is limited by the need to take the +list_lock once in a while to deal with partial slabs. That overhead is +governed by the order of the allocation for each slab. The allocations +can be influenced by kernel parameters: + +.. slub_min_objects=x (default 4) +.. slub_min_order=x (default 0) +.. slub_max_order=x (default 3 (PAGE_ALLOC_COSTLY_ORDER)) + +``slub_min_objects`` + allows to specify how many objects must at least fit into one + slab in order for the allocation order to be acceptable. In + general slub will be able to perform this number of + allocations on a slab without consulting centralized resources + (list_lock) where contention may occur. + +``slub_min_order`` + specifies a minim order of slabs. A similar effect like + ``slub_min_objects``. + +``slub_max_order`` + specified the order at which ``slub_min_objects`` should no + longer be checked. This is useful to avoid SLUB trying to + generate super large order pages to fit ``slub_min_objects`` + of a slab cache with large object sizes into one high order + page. Setting command line parameter + ``debug_guardpage_minorder=N`` (N > 0), forces setting + ``slub_max_order`` to 0, what cause minimum possible order of + slabs allocation. + +SLUB Debug output +================= + +Here is a sample of slub debug output:: + + ==================================================================== + BUG kmalloc-8: Redzone overwritten + -------------------------------------------------------------------- + + INFO: 0xc90f6d28-0xc90f6d2b. First byte 0x00 instead of 0xcc + INFO: Slab 0xc528c530 flags=0x400000c3 inuse=61 fp=0xc90f6d58 + INFO: Object 0xc90f6d20 @offset=3360 fp=0xc90f6d58 + INFO: Allocated in get_modalias+0x61/0xf5 age=53 cpu=1 pid=554 + + Bytes b4 0xc90f6d10: 00 00 00 00 00 00 00 00 5a 5a 5a 5a 5a 5a 5a 5a ........ZZZZZZZZ + Object 0xc90f6d20: 31 30 31 39 2e 30 30 35 1019.005 + Redzone 0xc90f6d28: 00 cc cc cc . + Padding 0xc90f6d50: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ + + [<c010523d>] dump_trace+0x63/0x1eb + [<c01053df>] show_trace_log_lvl+0x1a/0x2f + [<c010601d>] show_trace+0x12/0x14 + [<c0106035>] dump_stack+0x16/0x18 + [<c017e0fa>] object_err+0x143/0x14b + [<c017e2cc>] check_object+0x66/0x234 + [<c017eb43>] __slab_free+0x239/0x384 + [<c017f446>] kfree+0xa6/0xc6 + [<c02e2335>] get_modalias+0xb9/0xf5 + [<c02e23b7>] dmi_dev_uevent+0x27/0x3c + [<c027866a>] dev_uevent+0x1ad/0x1da + [<c0205024>] kobject_uevent_env+0x20a/0x45b + [<c020527f>] kobject_uevent+0xa/0xf + [<c02779f1>] store_uevent+0x4f/0x58 + [<c027758e>] dev_attr_store+0x29/0x2f + [<c01bec4f>] sysfs_write_file+0x16e/0x19c + [<c0183ba7>] vfs_write+0xd1/0x15a + [<c01841d7>] sys_write+0x3d/0x72 + [<c0104112>] sysenter_past_esp+0x5f/0x99 + [<b7f7b410>] 0xb7f7b410 + ======================= + + FIX kmalloc-8: Restoring Redzone 0xc90f6d28-0xc90f6d2b=0xcc + +If SLUB encounters a corrupted object (full detection requires the kernel +to be booted with slub_debug) then the following output will be dumped +into the syslog: + +1. Description of the problem encountered + + This will be a message in the system log starting with:: + + =============================================== + BUG <slab cache affected>: <What went wrong> + ----------------------------------------------- + + INFO: <corruption start>-<corruption_end> <more info> + INFO: Slab <address> <slab information> + INFO: Object <address> <object information> + INFO: Allocated in <kernel function> age=<jiffies since alloc> cpu=<allocated by + cpu> pid=<pid of the process> + INFO: Freed in <kernel function> age=<jiffies since free> cpu=<freed by cpu> + pid=<pid of the process> + + (Object allocation / free information is only available if SLAB_STORE_USER is + set for the slab. slub_debug sets that option) + +2. The object contents if an object was involved. + + Various types of lines can follow the BUG SLUB line: + + Bytes b4 <address> : <bytes> + Shows a few bytes before the object where the problem was detected. + Can be useful if the corruption does not stop with the start of the + object. + + Object <address> : <bytes> + The bytes of the object. If the object is inactive then the bytes + typically contain poison values. Any non-poison value shows a + corruption by a write after free. + + Redzone <address> : <bytes> + The Redzone following the object. The Redzone is used to detect + writes after the object. All bytes should always have the same + value. If there is any deviation then it is due to a write after + the object boundary. + + (Redzone information is only available if SLAB_RED_ZONE is set. + slub_debug sets that option) + + Padding <address> : <bytes> + Unused data to fill up the space in order to get the next object + properly aligned. In the debug case we make sure that there are + at least 4 bytes of padding. This allows the detection of writes + before the object. + +3. A stackdump + + The stackdump describes the location where the error was detected. The cause + of the corruption is may be more likely found by looking at the function that + allocated or freed the object. + +4. Report on how the problem was dealt with in order to ensure the continued + operation of the system. + + These are messages in the system log beginning with:: + + FIX <slab cache affected>: <corrective action taken> + + In the above sample SLUB found that the Redzone of an active object has + been overwritten. Here a string of 8 characters was written into a slab that + has the length of 8 characters. However, a 8 character string needs a + terminating 0. That zero has overwritten the first byte of the Redzone field. + After reporting the details of the issue encountered the FIX SLUB message + tells us that SLUB has restored the Redzone to its proper value and then + system operations continue. + +Emergency operations +==================== + +Minimal debugging (sanity checks alone) can be enabled by booting with:: + + slub_debug=F + +This will be generally be enough to enable the resiliency features of slub +which will keep the system running even if a bad kernel component will +keep corrupting objects. This may be important for production systems. +Performance will be impacted by the sanity checks and there will be a +continual stream of error messages to the syslog but no additional memory +will be used (unlike full debugging). + +No guarantees. The kernel component still needs to be fixed. Performance +may be optimized further by locating the slab that experiences corruption +and enabling debugging only for that cache + +I.e.:: + + slub_debug=F,dentry + +If the corruption occurs by writing after the end of the object then it +may be advisable to enable a Redzone to avoid corrupting the beginning +of other objects:: + + slub_debug=FZ,dentry + +Extended slabinfo mode and plotting +=================================== + +The ``slabinfo`` tool has a special 'extended' ('-X') mode that includes: + - Slabcache Totals + - Slabs sorted by size (up to -N <num> slabs, default 1) + - Slabs sorted by loss (up to -N <num> slabs, default 1) + +Additionally, in this mode ``slabinfo`` does not dynamically scale +sizes (G/M/K) and reports everything in bytes (this functionality is +also available to other slabinfo modes via '-B' option) which makes +reporting more precise and accurate. Moreover, in some sense the `-X' +mode also simplifies the analysis of slabs' behaviour, because its +output can be plotted using the ``slabinfo-gnuplot.sh`` script. So it +pushes the analysis from looking through the numbers (tons of numbers) +to something easier -- visual analysis. + +To generate plots: + +a) collect slabinfo extended records, for example:: + + while [ 1 ]; do slabinfo -X >> FOO_STATS; sleep 1; done + +b) pass stats file(-s) to ``slabinfo-gnuplot.sh`` script:: + + slabinfo-gnuplot.sh FOO_STATS [FOO_STATS2 .. FOO_STATSN] + + The ``slabinfo-gnuplot.sh`` script will pre-processes the collected records + and generates 3 png files (and 3 pre-processing cache files) per STATS + file: + - Slabcache Totals: FOO_STATS-totals.png + - Slabs sorted by size: FOO_STATS-slabs-by-size.png + - Slabs sorted by loss: FOO_STATS-slabs-by-loss.png + +Another use case, when ``slabinfo-gnuplot.sh`` can be useful, is when you +need to compare slabs' behaviour "prior to" and "after" some code +modification. To help you out there, ``slabinfo-gnuplot.sh`` script +can 'merge' the `Slabcache Totals` sections from different +measurements. To visually compare N plots: + +a) Collect as many STATS1, STATS2, .. STATSN files as you need:: + + while [ 1 ]; do slabinfo -X >> STATS<X>; sleep 1; done + +b) Pre-process those STATS files:: + + slabinfo-gnuplot.sh STATS1 STATS2 .. STATSN + +c) Execute ``slabinfo-gnuplot.sh`` in '-t' mode, passing all of the + generated pre-processed \*-totals:: + + slabinfo-gnuplot.sh -t STATS1-totals STATS2-totals .. STATSN-totals + + This will produce a single plot (png file). + + Plots, expectedly, can be large so some fluctuations or small spikes + can go unnoticed. To deal with that, ``slabinfo-gnuplot.sh`` has two + options to 'zoom-in'/'zoom-out': + + a) ``-s %d,%d`` -- overwrites the default image width and heigh + b) ``-r %d,%d`` -- specifies a range of samples to use (for example, + in ``slabinfo -X >> FOO_STATS; sleep 1;`` case, using a ``-r + 40,60`` range will plot only samples collected between 40th and + 60th seconds). + +Christoph Lameter, May 30, 2007 +Sergey Senozhatsky, October 23, 2015 diff --git a/Documentation/vm/slub.txt b/Documentation/vm/slub.txt deleted file mode 100644 index 84652419bff2..000000000000 --- a/Documentation/vm/slub.txt +++ /dev/null @@ -1,342 +0,0 @@ -Short users guide for SLUB --------------------------- - -The basic philosophy of SLUB is very different from SLAB. SLAB -requires rebuilding the kernel to activate debug options for all -slab caches. SLUB always includes full debugging but it is off by default. -SLUB can enable debugging only for selected slabs in order to avoid -an impact on overall system performance which may make a bug more -difficult to find. - -In order to switch debugging on one can add an option "slub_debug" -to the kernel command line. That will enable full debugging for -all slabs. - -Typically one would then use the "slabinfo" command to get statistical -data and perform operation on the slabs. By default slabinfo only lists -slabs that have data in them. See "slabinfo -h" for more options when -running the command. slabinfo can be compiled with - -gcc -o slabinfo tools/vm/slabinfo.c - -Some of the modes of operation of slabinfo require that slub debugging -be enabled on the command line. F.e. no tracking information will be -available without debugging on and validation can only partially -be performed if debugging was not switched on. - -Some more sophisticated uses of slub_debug: -------------------------------------------- - -Parameters may be given to slub_debug. If none is specified then full -debugging is enabled. Format: - -slub_debug=<Debug-Options> Enable options for all slabs -slub_debug=<Debug-Options>,<slab name> - Enable options only for select slabs - -Possible debug options are - F Sanity checks on (enables SLAB_DEBUG_CONSISTENCY_CHECKS - Sorry SLAB legacy issues) - Z Red zoning - P Poisoning (object and padding) - U User tracking (free and alloc) - T Trace (please only use on single slabs) - A Toggle failslab filter mark for the cache - O Switch debugging off for caches that would have - caused higher minimum slab orders - - Switch all debugging off (useful if the kernel is - configured with CONFIG_SLUB_DEBUG_ON) - -F.e. in order to boot just with sanity checks and red zoning one would specify: - - slub_debug=FZ - -Trying to find an issue in the dentry cache? Try - - slub_debug=,dentry - -to only enable debugging on the dentry cache. - -Red zoning and tracking may realign the slab. We can just apply sanity checks -to the dentry cache with - - slub_debug=F,dentry - -Debugging options may require the minimum possible slab order to increase as -a result of storing the metadata (for example, caches with PAGE_SIZE object -sizes). This has a higher liklihood of resulting in slab allocation errors -in low memory situations or if there's high fragmentation of memory. To -switch off debugging for such caches by default, use - - slub_debug=O - -In case you forgot to enable debugging on the kernel command line: It is -possible to enable debugging manually when the kernel is up. Look at the -contents of: - -/sys/kernel/slab/<slab name>/ - -Look at the writable files. Writing 1 to them will enable the -corresponding debug option. All options can be set on a slab that does -not contain objects. If the slab already contains objects then sanity checks -and tracing may only be enabled. The other options may cause the realignment -of objects. - -Careful with tracing: It may spew out lots of information and never stop if -used on the wrong slab. - -Slab merging ------------- - -If no debug options are specified then SLUB may merge similar slabs together -in order to reduce overhead and increase cache hotness of objects. -slabinfo -a displays which slabs were merged together. - -Slab validation ---------------- - -SLUB can validate all object if the kernel was booted with slub_debug. In -order to do so you must have the slabinfo tool. Then you can do - -slabinfo -v - -which will test all objects. Output will be generated to the syslog. - -This also works in a more limited way if boot was without slab debug. -In that case slabinfo -v simply tests all reachable objects. Usually -these are in the cpu slabs and the partial slabs. Full slabs are not -tracked by SLUB in a non debug situation. - -Getting more performance ------------------------- - -To some degree SLUB's performance is limited by the need to take the -list_lock once in a while to deal with partial slabs. That overhead is -governed by the order of the allocation for each slab. The allocations -can be influenced by kernel parameters: - -slub_min_objects=x (default 4) -slub_min_order=x (default 0) -slub_max_order=x (default 3 (PAGE_ALLOC_COSTLY_ORDER)) - -slub_min_objects allows to specify how many objects must at least fit -into one slab in order for the allocation order to be acceptable. -In general slub will be able to perform this number of allocations -on a slab without consulting centralized resources (list_lock) where -contention may occur. - -slub_min_order specifies a minim order of slabs. A similar effect like -slub_min_objects. - -slub_max_order specified the order at which slub_min_objects should no -longer be checked. This is useful to avoid SLUB trying to generate -super large order pages to fit slub_min_objects of a slab cache with -large object sizes into one high order page. Setting command line -parameter debug_guardpage_minorder=N (N > 0), forces setting -slub_max_order to 0, what cause minimum possible order of slabs -allocation. - -SLUB Debug output ------------------ - -Here is a sample of slub debug output: - -==================================================================== -BUG kmalloc-8: Redzone overwritten --------------------------------------------------------------------- - -INFO: 0xc90f6d28-0xc90f6d2b. First byte 0x00 instead of 0xcc -INFO: Slab 0xc528c530 flags=0x400000c3 inuse=61 fp=0xc90f6d58 -INFO: Object 0xc90f6d20 @offset=3360 fp=0xc90f6d58 -INFO: Allocated in get_modalias+0x61/0xf5 age=53 cpu=1 pid=554 - -Bytes b4 0xc90f6d10: 00 00 00 00 00 00 00 00 5a 5a 5a 5a 5a 5a 5a 5a ........ZZZZZZZZ - Object 0xc90f6d20: 31 30 31 39 2e 30 30 35 1019.005 - Redzone 0xc90f6d28: 00 cc cc cc . - Padding 0xc90f6d50: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ - - [<c010523d>] dump_trace+0x63/0x1eb - [<c01053df>] show_trace_log_lvl+0x1a/0x2f - [<c010601d>] show_trace+0x12/0x14 - [<c0106035>] dump_stack+0x16/0x18 - [<c017e0fa>] object_err+0x143/0x14b - [<c017e2cc>] check_object+0x66/0x234 - [<c017eb43>] __slab_free+0x239/0x384 - [<c017f446>] kfree+0xa6/0xc6 - [<c02e2335>] get_modalias+0xb9/0xf5 - [<c02e23b7>] dmi_dev_uevent+0x27/0x3c - [<c027866a>] dev_uevent+0x1ad/0x1da - [<c0205024>] kobject_uevent_env+0x20a/0x45b - [<c020527f>] kobject_uevent+0xa/0xf - [<c02779f1>] store_uevent+0x4f/0x58 - [<c027758e>] dev_attr_store+0x29/0x2f - [<c01bec4f>] sysfs_write_file+0x16e/0x19c - [<c0183ba7>] vfs_write+0xd1/0x15a - [<c01841d7>] sys_write+0x3d/0x72 - [<c0104112>] sysenter_past_esp+0x5f/0x99 - [<b7f7b410>] 0xb7f7b410 - ======================= - -FIX kmalloc-8: Restoring Redzone 0xc90f6d28-0xc90f6d2b=0xcc - -If SLUB encounters a corrupted object (full detection requires the kernel -to be booted with slub_debug) then the following output will be dumped -into the syslog: - -1. Description of the problem encountered - -This will be a message in the system log starting with - -=============================================== -BUG <slab cache affected>: <What went wrong> ------------------------------------------------ - -INFO: <corruption start>-<corruption_end> <more info> -INFO: Slab <address> <slab information> -INFO: Object <address> <object information> -INFO: Allocated in <kernel function> age=<jiffies since alloc> cpu=<allocated by - cpu> pid=<pid of the process> -INFO: Freed in <kernel function> age=<jiffies since free> cpu=<freed by cpu> - pid=<pid of the process> - -(Object allocation / free information is only available if SLAB_STORE_USER is -set for the slab. slub_debug sets that option) - -2. The object contents if an object was involved. - -Various types of lines can follow the BUG SLUB line: - -Bytes b4 <address> : <bytes> - Shows a few bytes before the object where the problem was detected. - Can be useful if the corruption does not stop with the start of the - object. - -Object <address> : <bytes> - The bytes of the object. If the object is inactive then the bytes - typically contain poison values. Any non-poison value shows a - corruption by a write after free. - -Redzone <address> : <bytes> - The Redzone following the object. The Redzone is used to detect - writes after the object. All bytes should always have the same - value. If there is any deviation then it is due to a write after - the object boundary. - - (Redzone information is only available if SLAB_RED_ZONE is set. - slub_debug sets that option) - -Padding <address> : <bytes> - Unused data to fill up the space in order to get the next object - properly aligned. In the debug case we make sure that there are - at least 4 bytes of padding. This allows the detection of writes - before the object. - -3. A stackdump - -The stackdump describes the location where the error was detected. The cause -of the corruption is may be more likely found by looking at the function that -allocated or freed the object. - -4. Report on how the problem was dealt with in order to ensure the continued -operation of the system. - -These are messages in the system log beginning with - -FIX <slab cache affected>: <corrective action taken> - -In the above sample SLUB found that the Redzone of an active object has -been overwritten. Here a string of 8 characters was written into a slab that -has the length of 8 characters. However, a 8 character string needs a -terminating 0. That zero has overwritten the first byte of the Redzone field. -After reporting the details of the issue encountered the FIX SLUB message -tells us that SLUB has restored the Redzone to its proper value and then -system operations continue. - -Emergency operations: ---------------------- - -Minimal debugging (sanity checks alone) can be enabled by booting with - - slub_debug=F - -This will be generally be enough to enable the resiliency features of slub -which will keep the system running even if a bad kernel component will -keep corrupting objects. This may be important for production systems. -Performance will be impacted by the sanity checks and there will be a -continual stream of error messages to the syslog but no additional memory -will be used (unlike full debugging). - -No guarantees. The kernel component still needs to be fixed. Performance -may be optimized further by locating the slab that experiences corruption -and enabling debugging only for that cache - -I.e. - - slub_debug=F,dentry - -If the corruption occurs by writing after the end of the object then it -may be advisable to enable a Redzone to avoid corrupting the beginning -of other objects. - - slub_debug=FZ,dentry - -Extended slabinfo mode and plotting ------------------------------------ - -The slabinfo tool has a special 'extended' ('-X') mode that includes: - - Slabcache Totals - - Slabs sorted by size (up to -N <num> slabs, default 1) - - Slabs sorted by loss (up to -N <num> slabs, default 1) - -Additionally, in this mode slabinfo does not dynamically scale sizes (G/M/K) -and reports everything in bytes (this functionality is also available to -other slabinfo modes via '-B' option) which makes reporting more precise and -accurate. Moreover, in some sense the `-X' mode also simplifies the analysis -of slabs' behaviour, because its output can be plotted using the -slabinfo-gnuplot.sh script. So it pushes the analysis from looking through -the numbers (tons of numbers) to something easier -- visual analysis. - -To generate plots: -a) collect slabinfo extended records, for example: - - while [ 1 ]; do slabinfo -X >> FOO_STATS; sleep 1; done - -b) pass stats file(-s) to slabinfo-gnuplot.sh script: - slabinfo-gnuplot.sh FOO_STATS [FOO_STATS2 .. FOO_STATSN] - -The slabinfo-gnuplot.sh script will pre-processes the collected records -and generates 3 png files (and 3 pre-processing cache files) per STATS -file: - - Slabcache Totals: FOO_STATS-totals.png - - Slabs sorted by size: FOO_STATS-slabs-by-size.png - - Slabs sorted by loss: FOO_STATS-slabs-by-loss.png - -Another use case, when slabinfo-gnuplot can be useful, is when you need -to compare slabs' behaviour "prior to" and "after" some code modification. -To help you out there, slabinfo-gnuplot.sh script can 'merge' the -`Slabcache Totals` sections from different measurements. To visually -compare N plots: - -a) Collect as many STATS1, STATS2, .. STATSN files as you need - while [ 1 ]; do slabinfo -X >> STATS<X>; sleep 1; done - -b) Pre-process those STATS files - slabinfo-gnuplot.sh STATS1 STATS2 .. STATSN - -c) Execute slabinfo-gnuplot.sh in '-t' mode, passing all of the -generated pre-processed *-totals - slabinfo-gnuplot.sh -t STATS1-totals STATS2-totals .. STATSN-totals - -This will produce a single plot (png file). - -Plots, expectedly, can be large so some fluctuations or small spikes -can go unnoticed. To deal with that, `slabinfo-gnuplot.sh' has two -options to 'zoom-in'/'zoom-out': - a) -s %d,%d overwrites the default image width and heigh - b) -r %d,%d specifies a range of samples to use (for example, - in `slabinfo -X >> FOO_STATS; sleep 1;' case, using - a "-r 40,60" range will plot only samples collected - between 40th and 60th seconds). - -Christoph Lameter, May 30, 2007 -Sergey Senozhatsky, October 23, 2015 diff --git a/Documentation/vm/split_page_table_lock b/Documentation/vm/split_page_table_lock.rst index 62842a857dab..889b00be469f 100644 --- a/Documentation/vm/split_page_table_lock +++ b/Documentation/vm/split_page_table_lock.rst @@ -1,3 +1,6 @@ +.. _split_page_table_lock: + +===================== Split page table lock ===================== @@ -11,6 +14,7 @@ access to the table. At the moment we use split lock for PTE and PMD tables. Access to higher level tables protected by mm->page_table_lock. There are helpers to lock/unlock a table and other accessor functions: + - pte_offset_map_lock() maps pte and takes PTE table lock, returns pointer to the taken lock; @@ -34,12 +38,13 @@ Split page table lock for PMD tables is enabled, if it's enabled for PTE tables and the architecture supports it (see below). Hugetlb and split page table lock ---------------------------------- +================================= Hugetlb can support several page sizes. We use split lock only for PMD level, but not for PUD. Hugetlb-specific helpers: + - huge_pte_lock() takes pmd split lock for PMD_SIZE page, mm->page_table_lock otherwise; @@ -47,7 +52,7 @@ Hugetlb-specific helpers: returns pointer to table lock; Support of split page table lock by an architecture ---------------------------------------------------- +=================================================== There's no need in special enabling of PTE split page table lock: everything required is done by pgtable_page_ctor() and pgtable_page_dtor(), @@ -73,7 +78,7 @@ NOTE: pgtable_page_ctor() and pgtable_pmd_page_ctor() can fail -- it must be handled properly. page->ptl ---------- +========= page->ptl is used to access split page table lock, where 'page' is struct page of page containing the table. It shares storage with page->private @@ -81,6 +86,7 @@ page of page containing the table. It shares storage with page->private To avoid increasing size of struct page and have best performance, we use a trick: + - if spinlock_t fits into long, we use page->ptr as spinlock, so we can avoid indirect access and save a cache line. - if size of spinlock_t is bigger then size of long, we use page->ptl as diff --git a/Documentation/vm/swap_numa.txt b/Documentation/vm/swap_numa.rst index d5960c9124f5..e0466f2db8fa 100644 --- a/Documentation/vm/swap_numa.txt +++ b/Documentation/vm/swap_numa.rst @@ -1,5 +1,8 @@ +.. _swap_numa: + +=========================================== Automatically bind swap device to numa node -------------------------------------------- +=========================================== If the system has more than one swap device and swap device has the node information, we can make use of this information to decide which swap @@ -7,15 +10,16 @@ device to use in get_swap_pages() to get better performance. How to use this feature ------------------------ +======================= Swap device has priority and that decides the order of it to be used. To make use of automatically binding, there is no need to manipulate priority settings for swap devices. e.g. on a 2 node machine, assume 2 swap devices swapA and swapB, with swapA attached to node 0 and swapB attached to node 1, are going -to be swapped on. Simply swapping them on by doing: -# swapon /dev/swapA -# swapon /dev/swapB +to be swapped on. Simply swapping them on by doing:: + + # swapon /dev/swapA + # swapon /dev/swapB Then node 0 will use the two swap devices in the order of swapA then swapB and node 1 will use the two swap devices in the order of swapB then swapA. Note @@ -24,32 +28,39 @@ that the order of them being swapped on doesn't matter. A more complex example on a 4 node machine. Assume 6 swap devices are going to be swapped on: swapA and swapB are attached to node 0, swapC is attached to node 1, swapD and swapE are attached to node 2 and swapF is attached to node3. -The way to swap them on is the same as above: -# swapon /dev/swapA -# swapon /dev/swapB -# swapon /dev/swapC -# swapon /dev/swapD -# swapon /dev/swapE -# swapon /dev/swapF - -Then node 0 will use them in the order of: -swapA/swapB -> swapC -> swapD -> swapE -> swapF +The way to swap them on is the same as above:: + + # swapon /dev/swapA + # swapon /dev/swapB + # swapon /dev/swapC + # swapon /dev/swapD + # swapon /dev/swapE + # swapon /dev/swapF + +Then node 0 will use them in the order of:: + + swapA/swapB -> swapC -> swapD -> swapE -> swapF + swapA and swapB will be used in a round robin mode before any other swap device. -node 1 will use them in the order of: -swapC -> swapA -> swapB -> swapD -> swapE -> swapF +node 1 will use them in the order of:: + + swapC -> swapA -> swapB -> swapD -> swapE -> swapF + +node 2 will use them in the order of:: + + swapD/swapE -> swapA -> swapB -> swapC -> swapF -node 2 will use them in the order of: -swapD/swapE -> swapA -> swapB -> swapC -> swapF Similaly, swapD and swapE will be used in a round robin mode before any other swap devices. -node 3 will use them in the order of: -swapF -> swapA -> swapB -> swapC -> swapD -> swapE +node 3 will use them in the order of:: + + swapF -> swapA -> swapB -> swapC -> swapD -> swapE Implementation details ----------------------- +====================== The current code uses a priority based list, swap_avail_list, to decide which swap device to use and if multiple swap devices share the same diff --git a/Documentation/vm/transhuge.rst b/Documentation/vm/transhuge.rst new file mode 100644 index 000000000000..a8cf6809e36e --- /dev/null +++ b/Documentation/vm/transhuge.rst @@ -0,0 +1,197 @@ +.. _transhuge: + +============================ +Transparent Hugepage Support +============================ + +This document describes design principles Transparent Hugepage (THP) +Support and its interaction with other parts of the memory management. + +Design principles +================= + +- "graceful fallback": mm components which don't have transparent hugepage + knowledge fall back to breaking huge pmd mapping into table of ptes and, + if necessary, split a transparent hugepage. Therefore these components + can continue working on the regular pages or regular pte mappings. + +- if a hugepage allocation fails because of memory fragmentation, + regular pages should be gracefully allocated instead and mixed in + the same vma without any failure or significant delay and without + userland noticing + +- if some task quits and more hugepages become available (either + immediately in the buddy or through the VM), guest physical memory + backed by regular pages should be relocated on hugepages + automatically (with khugepaged) + +- it doesn't require memory reservation and in turn it uses hugepages + whenever possible (the only possible reservation here is kernelcore= + to avoid unmovable pages to fragment all the memory but such a tweak + is not specific to transparent hugepage support and it's a generic + feature that applies to all dynamic high order allocations in the + kernel) + +get_user_pages and follow_page +============================== + +get_user_pages and follow_page if run on a hugepage, will return the +head or tail pages as usual (exactly as they would do on +hugetlbfs). Most gup users will only care about the actual physical +address of the page and its temporary pinning to release after the I/O +is complete, so they won't ever notice the fact the page is huge. But +if any driver is going to mangle over the page structure of the tail +page (like for checking page->mapping or other bits that are relevant +for the head page and not the tail page), it should be updated to jump +to check head page instead. Taking reference on any head/tail page would +prevent page from being split by anyone. + +.. note:: + these aren't new constraints to the GUP API, and they match the + same constrains that applies to hugetlbfs too, so any driver capable + of handling GUP on hugetlbfs will also work fine on transparent + hugepage backed mappings. + +In case you can't handle compound pages if they're returned by +follow_page, the FOLL_SPLIT bit can be specified as parameter to +follow_page, so that it will split the hugepages before returning +them. Migration for example passes FOLL_SPLIT as parameter to +follow_page because it's not hugepage aware and in fact it can't work +at all on hugetlbfs (but it instead works fine on transparent +hugepages thanks to FOLL_SPLIT). migration simply can't deal with +hugepages being returned (as it's not only checking the pfn of the +page and pinning it during the copy but it pretends to migrate the +memory in regular page sizes and with regular pte/pmd mappings). + +Graceful fallback +================= + +Code walking pagetables but unaware about huge pmds can simply call +split_huge_pmd(vma, pmd, addr) where the pmd is the one returned by +pmd_offset. It's trivial to make the code transparent hugepage aware +by just grepping for "pmd_offset" and adding split_huge_pmd where +missing after pmd_offset returns the pmd. Thanks to the graceful +fallback design, with a one liner change, you can avoid to write +hundred if not thousand of lines of complex code to make your code +hugepage aware. + +If you're not walking pagetables but you run into a physical hugepage +but you can't handle it natively in your code, you can split it by +calling split_huge_page(page). This is what the Linux VM does before +it tries to swapout the hugepage for example. split_huge_page() can fail +if the page is pinned and you must handle this correctly. + +Example to make mremap.c transparent hugepage aware with a one liner +change:: + + diff --git a/mm/mremap.c b/mm/mremap.c + --- a/mm/mremap.c + +++ b/mm/mremap.c + @@ -41,6 +41,7 @@ static pmd_t *get_old_pmd(struct mm_stru + return NULL; + + pmd = pmd_offset(pud, addr); + + split_huge_pmd(vma, pmd, addr); + if (pmd_none_or_clear_bad(pmd)) + return NULL; + +Locking in hugepage aware code +============================== + +We want as much code as possible hugepage aware, as calling +split_huge_page() or split_huge_pmd() has a cost. + +To make pagetable walks huge pmd aware, all you need to do is to call +pmd_trans_huge() on the pmd returned by pmd_offset. You must hold the +mmap_sem in read (or write) mode to be sure an huge pmd cannot be +created from under you by khugepaged (khugepaged collapse_huge_page +takes the mmap_sem in write mode in addition to the anon_vma lock). If +pmd_trans_huge returns false, you just fallback in the old code +paths. If instead pmd_trans_huge returns true, you have to take the +page table lock (pmd_lock()) and re-run pmd_trans_huge. Taking the +page table lock will prevent the huge pmd to be converted into a +regular pmd from under you (split_huge_pmd can run in parallel to the +pagetable walk). If the second pmd_trans_huge returns false, you +should just drop the page table lock and fallback to the old code as +before. Otherwise you can proceed to process the huge pmd and the +hugepage natively. Once finished you can drop the page table lock. + +Refcounts and transparent huge pages +==================================== + +Refcounting on THP is mostly consistent with refcounting on other compound +pages: + + - get_page()/put_page() and GUP operate in head page's ->_refcount. + + - ->_refcount in tail pages is always zero: get_page_unless_zero() never + succeed on tail pages. + + - map/unmap of the pages with PTE entry increment/decrement ->_mapcount + on relevant sub-page of the compound page. + + - map/unmap of the whole compound page accounted in compound_mapcount + (stored in first tail page). For file huge pages, we also increment + ->_mapcount of all sub-pages in order to have race-free detection of + last unmap of subpages. + +PageDoubleMap() indicates that the page is *possibly* mapped with PTEs. + +For anonymous pages PageDoubleMap() also indicates ->_mapcount in all +subpages is offset up by one. This additional reference is required to +get race-free detection of unmap of subpages when we have them mapped with +both PMDs and PTEs. + +This is optimization required to lower overhead of per-subpage mapcount +tracking. The alternative is alter ->_mapcount in all subpages on each +map/unmap of the whole compound page. + +For anonymous pages, we set PG_double_map when a PMD of the page got split +for the first time, but still have PMD mapping. The additional references +go away with last compound_mapcount. + +File pages get PG_double_map set on first map of the page with PTE and +goes away when the page gets evicted from page cache. + +split_huge_page internally has to distribute the refcounts in the head +page to the tail pages before clearing all PG_head/tail bits from the page +structures. It can be done easily for refcounts taken by page table +entries. But we don't have enough information on how to distribute any +additional pins (i.e. from get_user_pages). split_huge_page() fails any +requests to split pinned huge page: it expects page count to be equal to +sum of mapcount of all sub-pages plus one (split_huge_page caller must +have reference for head page). + +split_huge_page uses migration entries to stabilize page->_refcount and +page->_mapcount of anonymous pages. File pages just got unmapped. + +We safe against physical memory scanners too: the only legitimate way +scanner can get reference to a page is get_page_unless_zero(). + +All tail pages have zero ->_refcount until atomic_add(). This prevents the +scanner from getting a reference to the tail page up to that point. After the +atomic_add() we don't care about the ->_refcount value. We already known how +many references should be uncharged from the head page. + +For head page get_page_unless_zero() will succeed and we don't mind. It's +clear where reference should go after split: it will stay on head page. + +Note that split_huge_pmd() doesn't have any limitation on refcounting: +pmd can be split at any point and never fails. + +Partial unmap and deferred_split_huge_page() +============================================ + +Unmapping part of THP (with munmap() or other way) is not going to free +memory immediately. Instead, we detect that a subpage of THP is not in use +in page_remove_rmap() and queue the THP for splitting if memory pressure +comes. Splitting will free up unused subpages. + +Splitting the page right away is not an option due to locking context in +the place where we can detect partial unmap. It's also might be +counterproductive since in many cases partial unmap happens during exit(2) if +a THP crosses a VMA boundary. + +Function deferred_split_huge_page() is used to queue page for splitting. +The splitting itself will happen when we get memory pressure via shrinker +interface. diff --git a/Documentation/vm/transhuge.txt b/Documentation/vm/transhuge.txt deleted file mode 100644 index 4dde03b44ad1..000000000000 --- a/Documentation/vm/transhuge.txt +++ /dev/null @@ -1,527 +0,0 @@ -= Transparent Hugepage Support = - -== Objective == - -Performance critical computing applications dealing with large memory -working sets are already running on top of libhugetlbfs and in turn -hugetlbfs. Transparent Hugepage Support is an alternative means of -using huge pages for the backing of virtual memory with huge pages -that supports the automatic promotion and demotion of page sizes and -without the shortcomings of hugetlbfs. - -Currently it only works for anonymous memory mappings and tmpfs/shmem. -But in the future it can expand to other filesystems. - -The reason applications are running faster is because of two -factors. The first factor is almost completely irrelevant and it's not -of significant interest because it'll also have the downside of -requiring larger clear-page copy-page in page faults which is a -potentially negative effect. The first factor consists in taking a -single page fault for each 2M virtual region touched by userland (so -reducing the enter/exit kernel frequency by a 512 times factor). This -only matters the first time the memory is accessed for the lifetime of -a memory mapping. The second long lasting and much more important -factor will affect all subsequent accesses to the memory for the whole -runtime of the application. The second factor consist of two -components: 1) the TLB miss will run faster (especially with -virtualization using nested pagetables but almost always also on bare -metal without virtualization) and 2) a single TLB entry will be -mapping a much larger amount of virtual memory in turn reducing the -number of TLB misses. With virtualization and nested pagetables the -TLB can be mapped of larger size only if both KVM and the Linux guest -are using hugepages but a significant speedup already happens if only -one of the two is using hugepages just because of the fact the TLB -miss is going to run faster. - -== Design == - -- "graceful fallback": mm components which don't have transparent hugepage - knowledge fall back to breaking huge pmd mapping into table of ptes and, - if necessary, split a transparent hugepage. Therefore these components - can continue working on the regular pages or regular pte mappings. - -- if a hugepage allocation fails because of memory fragmentation, - regular pages should be gracefully allocated instead and mixed in - the same vma without any failure or significant delay and without - userland noticing - -- if some task quits and more hugepages become available (either - immediately in the buddy or through the VM), guest physical memory - backed by regular pages should be relocated on hugepages - automatically (with khugepaged) - -- it doesn't require memory reservation and in turn it uses hugepages - whenever possible (the only possible reservation here is kernelcore= - to avoid unmovable pages to fragment all the memory but such a tweak - is not specific to transparent hugepage support and it's a generic - feature that applies to all dynamic high order allocations in the - kernel) - -Transparent Hugepage Support maximizes the usefulness of free memory -if compared to the reservation approach of hugetlbfs by allowing all -unused memory to be used as cache or other movable (or even unmovable -entities). It doesn't require reservation to prevent hugepage -allocation failures to be noticeable from userland. It allows paging -and all other advanced VM features to be available on the -hugepages. It requires no modifications for applications to take -advantage of it. - -Applications however can be further optimized to take advantage of -this feature, like for example they've been optimized before to avoid -a flood of mmap system calls for every malloc(4k). Optimizing userland -is by far not mandatory and khugepaged already can take care of long -lived page allocations even for hugepage unaware applications that -deals with large amounts of memory. - -In certain cases when hugepages are enabled system wide, application -may end up allocating more memory resources. An application may mmap a -large region but only touch 1 byte of it, in that case a 2M page might -be allocated instead of a 4k page for no good. This is why it's -possible to disable hugepages system-wide and to only have them inside -MADV_HUGEPAGE madvise regions. - -Embedded systems should enable hugepages only inside madvise regions -to eliminate any risk of wasting any precious byte of memory and to -only run faster. - -Applications that gets a lot of benefit from hugepages and that don't -risk to lose memory by using hugepages, should use -madvise(MADV_HUGEPAGE) on their critical mmapped regions. - -== sysfs == - -Transparent Hugepage Support for anonymous memory can be entirely disabled -(mostly for debugging purposes) or only enabled inside MADV_HUGEPAGE -regions (to avoid the risk of consuming more memory resources) or enabled -system wide. This can be achieved with one of: - -echo always >/sys/kernel/mm/transparent_hugepage/enabled -echo madvise >/sys/kernel/mm/transparent_hugepage/enabled -echo never >/sys/kernel/mm/transparent_hugepage/enabled - -It's also possible to limit defrag efforts in the VM to generate -anonymous hugepages in case they're not immediately free to madvise -regions or to never try to defrag memory and simply fallback to regular -pages unless hugepages are immediately available. Clearly if we spend CPU -time to defrag memory, we would expect to gain even more by the fact we -use hugepages later instead of regular pages. This isn't always -guaranteed, but it may be more likely in case the allocation is for a -MADV_HUGEPAGE region. - -echo always >/sys/kernel/mm/transparent_hugepage/defrag -echo defer >/sys/kernel/mm/transparent_hugepage/defrag -echo defer+madvise >/sys/kernel/mm/transparent_hugepage/defrag -echo madvise >/sys/kernel/mm/transparent_hugepage/defrag -echo never >/sys/kernel/mm/transparent_hugepage/defrag - -"always" means that an application requesting THP will stall on allocation -failure and directly reclaim pages and compact memory in an effort to -allocate a THP immediately. This may be desirable for virtual machines -that benefit heavily from THP use and are willing to delay the VM start -to utilise them. - -"defer" means that an application will wake kswapd in the background -to reclaim pages and wake kcompactd to compact memory so that THP is -available in the near future. It's the responsibility of khugepaged -to then install the THP pages later. - -"defer+madvise" will enter direct reclaim and compaction like "always", but -only for regions that have used madvise(MADV_HUGEPAGE); all other regions -will wake kswapd in the background to reclaim pages and wake kcompactd to -compact memory so that THP is available in the near future. - -"madvise" will enter direct reclaim like "always" but only for regions -that are have used madvise(MADV_HUGEPAGE). This is the default behaviour. - -"never" should be self-explanatory. - -By default kernel tries to use huge zero page on read page fault to -anonymous mapping. It's possible to disable huge zero page by writing 0 -or enable it back by writing 1: - -echo 0 >/sys/kernel/mm/transparent_hugepage/use_zero_page -echo 1 >/sys/kernel/mm/transparent_hugepage/use_zero_page - -Some userspace (such as a test program, or an optimized memory allocation -library) may want to know the size (in bytes) of a transparent hugepage: - -cat /sys/kernel/mm/transparent_hugepage/hpage_pmd_size - -khugepaged will be automatically started when -transparent_hugepage/enabled is set to "always" or "madvise, and it'll -be automatically shutdown if it's set to "never". - -khugepaged runs usually at low frequency so while one may not want to -invoke defrag algorithms synchronously during the page faults, it -should be worth invoking defrag at least in khugepaged. However it's -also possible to disable defrag in khugepaged by writing 0 or enable -defrag in khugepaged by writing 1: - -echo 0 >/sys/kernel/mm/transparent_hugepage/khugepaged/defrag -echo 1 >/sys/kernel/mm/transparent_hugepage/khugepaged/defrag - -You can also control how many pages khugepaged should scan at each -pass: - -/sys/kernel/mm/transparent_hugepage/khugepaged/pages_to_scan - -and how many milliseconds to wait in khugepaged between each pass (you -can set this to 0 to run khugepaged at 100% utilization of one core): - -/sys/kernel/mm/transparent_hugepage/khugepaged/scan_sleep_millisecs - -and how many milliseconds to wait in khugepaged if there's an hugepage -allocation failure to throttle the next allocation attempt. - -/sys/kernel/mm/transparent_hugepage/khugepaged/alloc_sleep_millisecs - -The khugepaged progress can be seen in the number of pages collapsed: - -/sys/kernel/mm/transparent_hugepage/khugepaged/pages_collapsed - -for each pass: - -/sys/kernel/mm/transparent_hugepage/khugepaged/full_scans - -max_ptes_none specifies how many extra small pages (that are -not already mapped) can be allocated when collapsing a group -of small pages into one large page. - -/sys/kernel/mm/transparent_hugepage/khugepaged/max_ptes_none - -A higher value leads to use additional memory for programs. -A lower value leads to gain less thp performance. Value of -max_ptes_none can waste cpu time very little, you can -ignore it. - -max_ptes_swap specifies how many pages can be brought in from -swap when collapsing a group of pages into a transparent huge page. - -/sys/kernel/mm/transparent_hugepage/khugepaged/max_ptes_swap - -A higher value can cause excessive swap IO and waste -memory. A lower value can prevent THPs from being -collapsed, resulting fewer pages being collapsed into -THPs, and lower memory access performance. - -== Boot parameter == - -You can change the sysfs boot time defaults of Transparent Hugepage -Support by passing the parameter "transparent_hugepage=always" or -"transparent_hugepage=madvise" or "transparent_hugepage=never" -(without "") to the kernel command line. - -== Hugepages in tmpfs/shmem == - -You can control hugepage allocation policy in tmpfs with mount option -"huge=". It can have following values: - - - "always": - Attempt to allocate huge pages every time we need a new page; - - - "never": - Do not allocate huge pages; - - - "within_size": - Only allocate huge page if it will be fully within i_size. - Also respect fadvise()/madvise() hints; - - - "advise: - Only allocate huge pages if requested with fadvise()/madvise(); - -The default policy is "never". - -"mount -o remount,huge= /mountpoint" works fine after mount: remounting -huge=never will not attempt to break up huge pages at all, just stop more -from being allocated. - -There's also sysfs knob to control hugepage allocation policy for internal -shmem mount: /sys/kernel/mm/transparent_hugepage/shmem_enabled. The mount -is used for SysV SHM, memfds, shared anonymous mmaps (of /dev/zero or -MAP_ANONYMOUS), GPU drivers' DRM objects, Ashmem. - -In addition to policies listed above, shmem_enabled allows two further -values: - - - "deny": - For use in emergencies, to force the huge option off from - all mounts; - - "force": - Force the huge option on for all - very useful for testing; - -== Need of application restart == - -The transparent_hugepage/enabled values and tmpfs mount option only affect -future behavior. So to make them effective you need to restart any -application that could have been using hugepages. This also applies to the -regions registered in khugepaged. - -== Monitoring usage == - -The number of anonymous transparent huge pages currently used by the -system is available by reading the AnonHugePages field in /proc/meminfo. -To identify what applications are using anonymous transparent huge pages, -it is necessary to read /proc/PID/smaps and count the AnonHugePages fields -for each mapping. - -The number of file transparent huge pages mapped to userspace is available -by reading ShmemPmdMapped and ShmemHugePages fields in /proc/meminfo. -To identify what applications are mapping file transparent huge pages, it -is necessary to read /proc/PID/smaps and count the FileHugeMapped fields -for each mapping. - -Note that reading the smaps file is expensive and reading it -frequently will incur overhead. - -There are a number of counters in /proc/vmstat that may be used to -monitor how successfully the system is providing huge pages for use. - -thp_fault_alloc is incremented every time a huge page is successfully - allocated to handle a page fault. This applies to both the - first time a page is faulted and for COW faults. - -thp_collapse_alloc is incremented by khugepaged when it has found - a range of pages to collapse into one huge page and has - successfully allocated a new huge page to store the data. - -thp_fault_fallback is incremented if a page fault fails to allocate - a huge page and instead falls back to using small pages. - -thp_collapse_alloc_failed is incremented if khugepaged found a range - of pages that should be collapsed into one huge page but failed - the allocation. - -thp_file_alloc is incremented every time a file huge page is successfully - allocated. - -thp_file_mapped is incremented every time a file huge page is mapped into - user address space. - -thp_split_page is incremented every time a huge page is split into base - pages. This can happen for a variety of reasons but a common - reason is that a huge page is old and is being reclaimed. - This action implies splitting all PMD the page mapped with. - -thp_split_page_failed is incremented if kernel fails to split huge - page. This can happen if the page was pinned by somebody. - -thp_deferred_split_page is incremented when a huge page is put onto split - queue. This happens when a huge page is partially unmapped and - splitting it would free up some memory. Pages on split queue are - going to be split under memory pressure. - -thp_split_pmd is incremented every time a PMD split into table of PTEs. - This can happen, for instance, when application calls mprotect() or - munmap() on part of huge page. It doesn't split huge page, only - page table entry. - -thp_zero_page_alloc is incremented every time a huge zero page is - successfully allocated. It includes allocations which where - dropped due race with other allocation. Note, it doesn't count - every map of the huge zero page, only its allocation. - -thp_zero_page_alloc_failed is incremented if kernel fails to allocate - huge zero page and falls back to using small pages. - -As the system ages, allocating huge pages may be expensive as the -system uses memory compaction to copy data around memory to free a -huge page for use. There are some counters in /proc/vmstat to help -monitor this overhead. - -compact_stall is incremented every time a process stalls to run - memory compaction so that a huge page is free for use. - -compact_success is incremented if the system compacted memory and - freed a huge page for use. - -compact_fail is incremented if the system tries to compact memory - but failed. - -compact_pages_moved is incremented each time a page is moved. If - this value is increasing rapidly, it implies that the system - is copying a lot of data to satisfy the huge page allocation. - It is possible that the cost of copying exceeds any savings - from reduced TLB misses. - -compact_pagemigrate_failed is incremented when the underlying mechanism - for moving a page failed. - -compact_blocks_moved is incremented each time memory compaction examines - a huge page aligned range of pages. - -It is possible to establish how long the stalls were using the function -tracer to record how long was spent in __alloc_pages_nodemask and -using the mm_page_alloc tracepoint to identify which allocations were -for huge pages. - -== get_user_pages and follow_page == - -get_user_pages and follow_page if run on a hugepage, will return the -head or tail pages as usual (exactly as they would do on -hugetlbfs). Most gup users will only care about the actual physical -address of the page and its temporary pinning to release after the I/O -is complete, so they won't ever notice the fact the page is huge. But -if any driver is going to mangle over the page structure of the tail -page (like for checking page->mapping or other bits that are relevant -for the head page and not the tail page), it should be updated to jump -to check head page instead. Taking reference on any head/tail page would -prevent page from being split by anyone. - -NOTE: these aren't new constraints to the GUP API, and they match the -same constrains that applies to hugetlbfs too, so any driver capable -of handling GUP on hugetlbfs will also work fine on transparent -hugepage backed mappings. - -In case you can't handle compound pages if they're returned by -follow_page, the FOLL_SPLIT bit can be specified as parameter to -follow_page, so that it will split the hugepages before returning -them. Migration for example passes FOLL_SPLIT as parameter to -follow_page because it's not hugepage aware and in fact it can't work -at all on hugetlbfs (but it instead works fine on transparent -hugepages thanks to FOLL_SPLIT). migration simply can't deal with -hugepages being returned (as it's not only checking the pfn of the -page and pinning it during the copy but it pretends to migrate the -memory in regular page sizes and with regular pte/pmd mappings). - -== Optimizing the applications == - -To be guaranteed that the kernel will map a 2M page immediately in any -memory region, the mmap region has to be hugepage naturally -aligned. posix_memalign() can provide that guarantee. - -== Hugetlbfs == - -You can use hugetlbfs on a kernel that has transparent hugepage -support enabled just fine as always. No difference can be noted in -hugetlbfs other than there will be less overall fragmentation. All -usual features belonging to hugetlbfs are preserved and -unaffected. libhugetlbfs will also work fine as usual. - -== Graceful fallback == - -Code walking pagetables but unaware about huge pmds can simply call -split_huge_pmd(vma, pmd, addr) where the pmd is the one returned by -pmd_offset. It's trivial to make the code transparent hugepage aware -by just grepping for "pmd_offset" and adding split_huge_pmd where -missing after pmd_offset returns the pmd. Thanks to the graceful -fallback design, with a one liner change, you can avoid to write -hundred if not thousand of lines of complex code to make your code -hugepage aware. - -If you're not walking pagetables but you run into a physical hugepage -but you can't handle it natively in your code, you can split it by -calling split_huge_page(page). This is what the Linux VM does before -it tries to swapout the hugepage for example. split_huge_page() can fail -if the page is pinned and you must handle this correctly. - -Example to make mremap.c transparent hugepage aware with a one liner -change: - -diff --git a/mm/mremap.c b/mm/mremap.c ---- a/mm/mremap.c -+++ b/mm/mremap.c -@@ -41,6 +41,7 @@ static pmd_t *get_old_pmd(struct mm_stru - return NULL; - - pmd = pmd_offset(pud, addr); -+ split_huge_pmd(vma, pmd, addr); - if (pmd_none_or_clear_bad(pmd)) - return NULL; - -== Locking in hugepage aware code == - -We want as much code as possible hugepage aware, as calling -split_huge_page() or split_huge_pmd() has a cost. - -To make pagetable walks huge pmd aware, all you need to do is to call -pmd_trans_huge() on the pmd returned by pmd_offset. You must hold the -mmap_sem in read (or write) mode to be sure an huge pmd cannot be -created from under you by khugepaged (khugepaged collapse_huge_page -takes the mmap_sem in write mode in addition to the anon_vma lock). If -pmd_trans_huge returns false, you just fallback in the old code -paths. If instead pmd_trans_huge returns true, you have to take the -page table lock (pmd_lock()) and re-run pmd_trans_huge. Taking the -page table lock will prevent the huge pmd to be converted into a -regular pmd from under you (split_huge_pmd can run in parallel to the -pagetable walk). If the second pmd_trans_huge returns false, you -should just drop the page table lock and fallback to the old code as -before. Otherwise you can proceed to process the huge pmd and the -hugepage natively. Once finished you can drop the page table lock. - -== Refcounts and transparent huge pages == - -Refcounting on THP is mostly consistent with refcounting on other compound -pages: - - - get_page()/put_page() and GUP operate in head page's ->_refcount. - - - ->_refcount in tail pages is always zero: get_page_unless_zero() never - succeed on tail pages. - - - map/unmap of the pages with PTE entry increment/decrement ->_mapcount - on relevant sub-page of the compound page. - - - map/unmap of the whole compound page accounted in compound_mapcount - (stored in first tail page). For file huge pages, we also increment - ->_mapcount of all sub-pages in order to have race-free detection of - last unmap of subpages. - -PageDoubleMap() indicates that the page is *possibly* mapped with PTEs. - -For anonymous pages PageDoubleMap() also indicates ->_mapcount in all -subpages is offset up by one. This additional reference is required to -get race-free detection of unmap of subpages when we have them mapped with -both PMDs and PTEs. - -This is optimization required to lower overhead of per-subpage mapcount -tracking. The alternative is alter ->_mapcount in all subpages on each -map/unmap of the whole compound page. - -For anonymous pages, we set PG_double_map when a PMD of the page got split -for the first time, but still have PMD mapping. The additional references -go away with last compound_mapcount. - -File pages get PG_double_map set on first map of the page with PTE and -goes away when the page gets evicted from page cache. - -split_huge_page internally has to distribute the refcounts in the head -page to the tail pages before clearing all PG_head/tail bits from the page -structures. It can be done easily for refcounts taken by page table -entries. But we don't have enough information on how to distribute any -additional pins (i.e. from get_user_pages). split_huge_page() fails any -requests to split pinned huge page: it expects page count to be equal to -sum of mapcount of all sub-pages plus one (split_huge_page caller must -have reference for head page). - -split_huge_page uses migration entries to stabilize page->_refcount and -page->_mapcount of anonymous pages. File pages just got unmapped. - -We safe against physical memory scanners too: the only legitimate way -scanner can get reference to a page is get_page_unless_zero(). - -All tail pages have zero ->_refcount until atomic_add(). This prevents the -scanner from getting a reference to the tail page up to that point. After the -atomic_add() we don't care about the ->_refcount value. We already known how -many references should be uncharged from the head page. - -For head page get_page_unless_zero() will succeed and we don't mind. It's -clear where reference should go after split: it will stay on head page. - -Note that split_huge_pmd() doesn't have any limitation on refcounting: -pmd can be split at any point and never fails. - -== Partial unmap and deferred_split_huge_page() == - -Unmapping part of THP (with munmap() or other way) is not going to free -memory immediately. Instead, we detect that a subpage of THP is not in use -in page_remove_rmap() and queue the THP for splitting if memory pressure -comes. Splitting will free up unused subpages. - -Splitting the page right away is not an option due to locking context in -the place where we can detect partial unmap. It's also might be -counterproductive since in many cases partial unmap happens during exit(2) if -a THP crosses a VMA boundary. - -Function deferred_split_huge_page() is used to queue page for splitting. -The splitting itself will happen when we get memory pressure via shrinker -interface. diff --git a/Documentation/vm/unevictable-lru.txt b/Documentation/vm/unevictable-lru.rst index e14718572476..fdd84cb8d511 100644 --- a/Documentation/vm/unevictable-lru.txt +++ b/Documentation/vm/unevictable-lru.rst @@ -1,37 +1,13 @@ - ============================== - UNEVICTABLE LRU INFRASTRUCTURE - ============================== - -======== -CONTENTS -======== - - (*) The Unevictable LRU - - - The unevictable page list. - - Memory control group interaction. - - Marking address spaces unevictable. - - Detecting Unevictable Pages. - - vmscan's handling of unevictable pages. - - (*) mlock()'d pages. - - - History. - - Basic management. - - mlock()/mlockall() system call handling. - - Filtering special vmas. - - munlock()/munlockall() system call handling. - - Migrating mlocked pages. - - Compacting mlocked pages. - - mmap(MAP_LOCKED) system call handling. - - munmap()/exit()/exec() system call handling. - - try_to_unmap(). - - try_to_munlock() reverse map scan. - - Page reclaim in shrink_*_list(). +.. _unevictable_lru: +============================== +Unevictable LRU Infrastructure +============================== -============ -INTRODUCTION +.. contents:: :local: + + +Introduction ============ This document describes the Linux memory manager's "Unevictable LRU" @@ -46,8 +22,8 @@ details - the "what does it do?" - by reading the code. One hopes that the descriptions below add value by provide the answer to "why does it do that?". -=================== -THE UNEVICTABLE LRU + +The Unevictable LRU =================== The Unevictable LRU facility adds an additional LRU list to track unevictable @@ -66,17 +42,17 @@ completely unresponsive. The unevictable list addresses the following classes of unevictable pages: - (*) Those owned by ramfs. + * Those owned by ramfs. - (*) Those mapped into SHM_LOCK'd shared memory regions. + * Those mapped into SHM_LOCK'd shared memory regions. - (*) Those mapped into VM_LOCKED [mlock()ed] VMAs. + * Those mapped into VM_LOCKED [mlock()ed] VMAs. The infrastructure may also be able to handle other conditions that make pages unevictable, either by definition or by circumstance, in the future. -THE UNEVICTABLE PAGE LIST +The Unevictable Page List ------------------------- The Unevictable LRU infrastructure consists of an additional, per-zone, LRU list @@ -118,7 +94,7 @@ the unevictable list when one task has the page isolated from the LRU and other tasks are changing the "evictability" state of the page. -MEMORY CONTROL GROUP INTERACTION +Memory Control Group Interaction -------------------------------- The unevictable LRU facility interacts with the memory control group [aka @@ -144,7 +120,9 @@ effects: the control group to thrash or to OOM-kill tasks. -MARKING ADDRESS SPACES UNEVICTABLE +.. _mark_addr_space_unevict: + +Marking Address Spaces Unevictable ---------------------------------- For facilities such as ramfs none of the pages attached to the address space @@ -152,15 +130,15 @@ may be evicted. To prevent eviction of any such pages, the AS_UNEVICTABLE address space flag is provided, and this can be manipulated by a filesystem using a number of wrapper functions: - (*) void mapping_set_unevictable(struct address_space *mapping); + * ``void mapping_set_unevictable(struct address_space *mapping);`` Mark the address space as being completely unevictable. - (*) void mapping_clear_unevictable(struct address_space *mapping); + * ``void mapping_clear_unevictable(struct address_space *mapping);`` Mark the address space as being evictable. - (*) int mapping_unevictable(struct address_space *mapping); + * ``int mapping_unevictable(struct address_space *mapping);`` Query the address space, and return true if it is completely unevictable. @@ -177,12 +155,13 @@ These are currently used in two places in the kernel: ensure they're in memory. -DETECTING UNEVICTABLE PAGES +Detecting Unevictable Pages --------------------------- The function page_evictable() in vmscan.c determines whether a page is -evictable or not using the query function outlined above [see section "Marking -address spaces unevictable"] to check the AS_UNEVICTABLE flag. +evictable or not using the query function outlined above [see section +:ref:`Marking address spaces unevictable <mark_addr_space_unevict>`] +to check the AS_UNEVICTABLE flag. For address spaces that are so marked after being populated (as SHM regions might be), the lock action (eg: SHM_LOCK) can be lazy, and need not populate @@ -202,7 +181,7 @@ flag, PG_mlocked (as wrapped by PageMlocked()), which is set when a page is faulted into a VM_LOCKED vma, or found in a vma being VM_LOCKED. -VMSCAN'S HANDLING OF UNEVICTABLE PAGES +Vmscan's Handling of Unevictable Pages -------------------------------------- If unevictable pages are culled in the fault path, or moved to the unevictable @@ -233,8 +212,7 @@ extra evictabilty checks should not occur in the majority of calls to putback_lru_page(). -============= -MLOCKED PAGES +MLOCKED Pages ============= The unevictable page list is also useful for mlock(), in addition to ramfs and @@ -242,7 +220,7 @@ SYSV SHM. Note that mlock() is only available in CONFIG_MMU=y situations; in NOMMU situations, all mappings are effectively mlocked. -HISTORY +History ------- The "Unevictable mlocked Pages" infrastructure is based on work originally @@ -263,7 +241,7 @@ replaced by walking the reverse map to determine whether any VM_LOCKED VMAs mapped the page. More on this below. -BASIC MANAGEMENT +Basic Management ---------------- mlocked pages - pages mapped into a VM_LOCKED VMA - are a class of unevictable @@ -304,10 +282,10 @@ mlocked pages become unlocked and rescued from the unevictable list when: (4) before a page is COW'd in a VM_LOCKED VMA. -mlock()/mlockall() SYSTEM CALL HANDLING +mlock()/mlockall() System Call Handling --------------------------------------- -Both [do_]mlock() and [do_]mlockall() system call handlers call mlock_fixup() +Both [do\_]mlock() and [do\_]mlockall() system call handlers call mlock_fixup() for each VMA in the range specified by the call. In the case of mlockall(), this is the entire active address space of the task. Note that mlock_fixup() is used for both mlocking and munlocking a range of memory. A call to mlock() @@ -351,7 +329,7 @@ mlock_vma_page() is unable to isolate the page from the LRU, vmscan will handle it later if and when it attempts to reclaim the page. -FILTERING SPECIAL VMAS +Filtering Special VMAs ---------------------- mlock_fixup() filters several classes of "special" VMAs: @@ -379,8 +357,9 @@ VM_LOCKED flag. Therefore, we won't have to deal with them later during munlock(), munmap() or task exit. Neither does mlock_fixup() account these VMAs against the task's "locked_vm". +.. _munlock_munlockall_handling: -munlock()/munlockall() SYSTEM CALL HANDLING +munlock()/munlockall() System Call Handling ------------------------------------------- The munlock() and munlockall() system calls are handled by the same functions - @@ -426,7 +405,7 @@ This is fine, because we'll catch it later if and if vmscan tries to reclaim the page. This should be relatively rare. -MIGRATING MLOCKED PAGES +Migrating MLOCKED Pages ----------------------- A page that is being migrated has been isolated from the LRU lists and is held @@ -451,7 +430,7 @@ list because of a race between munlock and migration, page migration uses the putback_lru_page() function to add migrated pages back to the LRU. -COMPACTING MLOCKED PAGES +Compacting MLOCKED Pages ------------------------ The unevictable LRU can be scanned for compactable regions and the default @@ -461,7 +440,7 @@ unevictable LRU is enabled, the work of compaction is mostly handled by the page migration code and the same work flow as described in MIGRATING MLOCKED PAGES will apply. -MLOCKING TRANSPARENT HUGE PAGES +MLOCKING Transparent Huge Pages ------------------------------- A transparent huge page is represented by a single entry on an LRU list. @@ -483,7 +462,7 @@ to unevictable LRU and the rest can be reclaimed. See also comment in follow_trans_huge_pmd(). -mmap(MAP_LOCKED) SYSTEM CALL HANDLING +mmap(MAP_LOCKED) System Call Handling ------------------------------------- In addition the mlock()/mlockall() system calls, an application can request @@ -514,7 +493,7 @@ memory range accounted as locked_vm, as the protections could be changed later and pages allocated into that region. -munmap()/exit()/exec() SYSTEM CALL HANDLING +munmap()/exit()/exec() System Call Handling ------------------------------------------- When unmapping an mlocked region of memory, whether by an explicit call to @@ -568,16 +547,18 @@ munlock or munmap system calls, mm teardown (munlock_vma_pages_all), reclaim, holepunching, and truncation of file pages and their anonymous COWed pages. -try_to_munlock() REVERSE MAP SCAN +try_to_munlock() Reverse Map Scan --------------------------------- - [!] TODO/FIXME: a better name might be page_mlocked() - analogous to the - page_referenced() reverse map walker. +.. warning:: + [!] TODO/FIXME: a better name might be page_mlocked() - analogous to the + page_referenced() reverse map walker. -When munlock_vma_page() [see section "munlock()/munlockall() System Call -Handling" above] tries to munlock a page, it needs to determine whether or not -the page is mapped by any VM_LOCKED VMA without actually attempting to unmap -all PTEs from the page. For this purpose, the unevictable/mlock infrastructure +When munlock_vma_page() [see section :ref:`munlock()/munlockall() System Call +Handling <munlock_munlockall_handling>` above] tries to munlock a +page, it needs to determine whether or not the page is mapped by any +VM_LOCKED VMA without actually attempting to unmap all PTEs from the +page. For this purpose, the unevictable/mlock infrastructure introduced a variant of try_to_unmap() called try_to_munlock(). try_to_munlock() calls the same functions as try_to_unmap() for anonymous and @@ -595,7 +576,7 @@ large region or tearing down a large address space that has been mlocked via mlockall(), overall this is a fairly rare event. -PAGE RECLAIM IN shrink_*_list() +Page Reclaim in shrink_*_list() ------------------------------- shrink_active_list() culls any obviously unevictable pages - i.e. diff --git a/Documentation/vm/z3fold.txt b/Documentation/vm/z3fold.rst index 38e4dac810b6..224e3c61d686 100644 --- a/Documentation/vm/z3fold.txt +++ b/Documentation/vm/z3fold.rst @@ -1,5 +1,8 @@ +.. _z3fold: + +====== z3fold ------- +====== z3fold is a special purpose allocator for storing compressed pages. It is designed to store up to three compressed pages per physical page. @@ -7,6 +10,7 @@ It is a zbud derivative which allows for higher compression ratio keeping the simplicity and determinism of its predecessor. The main differences between z3fold and zbud are: + * unlike zbud, z3fold allows for up to PAGE_SIZE allocations * z3fold can hold up to 3 compressed pages in its page * z3fold doesn't export any API itself and is thus intended to be used diff --git a/Documentation/vm/zsmalloc.txt b/Documentation/vm/zsmalloc.rst index 64ed63c4f69d..6e79893d6132 100644 --- a/Documentation/vm/zsmalloc.txt +++ b/Documentation/vm/zsmalloc.rst @@ -1,5 +1,8 @@ +.. _zsmalloc: + +======== zsmalloc --------- +======== This allocator is designed for use with zram. Thus, the allocator is supposed to work well under low memory conditions. In particular, it @@ -31,40 +34,49 @@ be mapped using zs_map_object() to get a usable pointer and subsequently unmapped using zs_unmap_object(). stat ----- +==== With CONFIG_ZSMALLOC_STAT, we could see zsmalloc internal information via -/sys/kernel/debug/zsmalloc/<user name>. Here is a sample of stat output: +``/sys/kernel/debug/zsmalloc/<user name>``. Here is a sample of stat output:: -# cat /sys/kernel/debug/zsmalloc/zram0/classes + # cat /sys/kernel/debug/zsmalloc/zram0/classes class size almost_full almost_empty obj_allocated obj_used pages_used pages_per_zspage - .. - .. + ... + ... 9 176 0 1 186 129 8 4 10 192 1 0 2880 2872 135 3 11 208 0 1 819 795 42 2 12 224 0 1 219 159 12 4 - .. - .. + ... + ... + +class + index +size + object size zspage stores +almost_empty + the number of ZS_ALMOST_EMPTY zspages(see below) +almost_full + the number of ZS_ALMOST_FULL zspages(see below) +obj_allocated + the number of objects allocated +obj_used + the number of objects allocated to the user +pages_used + the number of pages allocated for the class +pages_per_zspage + the number of 0-order pages to make a zspage -class: index -size: object size zspage stores -almost_empty: the number of ZS_ALMOST_EMPTY zspages(see below) -almost_full: the number of ZS_ALMOST_FULL zspages(see below) -obj_allocated: the number of objects allocated -obj_used: the number of objects allocated to the user -pages_used: the number of pages allocated for the class -pages_per_zspage: the number of 0-order pages to make a zspage +We assign a zspage to ZS_ALMOST_EMPTY fullness group when n <= N / f, where -We assign a zspage to ZS_ALMOST_EMPTY fullness group when: - n <= N / f, where -n = number of allocated objects -N = total number of objects zspage can store -f = fullness_threshold_frac(ie, 4 at the moment) +* n = number of allocated objects +* N = total number of objects zspage can store +* f = fullness_threshold_frac(ie, 4 at the moment) Similarly, we assign zspage to: - ZS_ALMOST_FULL when n > N / f - ZS_EMPTY when n == 0 - ZS_FULL when n == N + +* ZS_ALMOST_FULL when n > N / f +* ZS_EMPTY when n == 0 +* ZS_FULL when n == N diff --git a/Documentation/vm/zswap.txt b/Documentation/vm/zswap.rst index 0b3a1148f9f0..1444ecd40911 100644 --- a/Documentation/vm/zswap.txt +++ b/Documentation/vm/zswap.rst @@ -1,4 +1,11 @@ -Overview: +.. _zswap: + +===== +zswap +===== + +Overview +======== Zswap is a lightweight compressed cache for swap pages. It takes pages that are in the process of being swapped out and attempts to compress them into a @@ -7,32 +14,34 @@ for potentially reduced swap I/O. This trade-off can also result in a significant performance improvement if reads from the compressed cache are faster than reads from a swap device. -NOTE: Zswap is a new feature as of v3.11 and interacts heavily with memory -reclaim. This interaction has not been fully explored on the large set of -potential configurations and workloads that exist. For this reason, zswap -is a work in progress and should be considered experimental. +.. note:: + Zswap is a new feature as of v3.11 and interacts heavily with memory + reclaim. This interaction has not been fully explored on the large set of + potential configurations and workloads that exist. For this reason, zswap + is a work in progress and should be considered experimental. + + Some potential benefits: -Some potential benefits: * Desktop/laptop users with limited RAM capacities can mitigate the - performance impact of swapping. + performance impact of swapping. * Overcommitted guests that share a common I/O resource can - dramatically reduce their swap I/O pressure, avoiding heavy handed I/O - throttling by the hypervisor. This allows more work to get done with less - impact to the guest workload and guests sharing the I/O subsystem + dramatically reduce their swap I/O pressure, avoiding heavy handed I/O + throttling by the hypervisor. This allows more work to get done with less + impact to the guest workload and guests sharing the I/O subsystem * Users with SSDs as swap devices can extend the life of the device by - drastically reducing life-shortening writes. + drastically reducing life-shortening writes. Zswap evicts pages from compressed cache on an LRU basis to the backing swap device when the compressed pool reaches its size limit. This requirement had been identified in prior community discussions. Zswap is disabled by default but can be enabled at boot time by setting -the "enabled" attribute to 1 at boot time. ie: zswap.enabled=1. Zswap +the ``enabled`` attribute to 1 at boot time. ie: ``zswap.enabled=1``. Zswap can also be enabled and disabled at runtime using the sysfs interface. An example command to enable zswap at runtime, assuming sysfs is mounted -at /sys, is: +at ``/sys``, is:: -echo 1 > /sys/module/zswap/parameters/enabled + echo 1 > /sys/module/zswap/parameters/enabled When zswap is disabled at runtime it will stop storing pages that are being swapped out. However, it will _not_ immediately write out or fault @@ -43,7 +52,8 @@ pages out of the compressed pool, a swapoff on the swap device(s) will fault back into memory all swapped out pages, including those in the compressed pool. -Design: +Design +====== Zswap receives pages for compression through the Frontswap API and is able to evict pages from its own compressed pool on an LRU basis and write them back to @@ -53,12 +63,12 @@ Zswap makes use of zpool for the managing the compressed memory pool. Each allocation in zpool is not directly accessible by address. Rather, a handle is returned by the allocation routine and that handle must be mapped before being accessed. The compressed memory pool grows on demand and shrinks as compressed -pages are freed. The pool is not preallocated. By default, a zpool of type -zbud is created, but it can be selected at boot time by setting the "zpool" -attribute, e.g. zswap.zpool=zbud. It can also be changed at runtime using the -sysfs "zpool" attribute, e.g. +pages are freed. The pool is not preallocated. By default, a zpool +of type zbud is created, but it can be selected at boot time by +setting the ``zpool`` attribute, e.g. ``zswap.zpool=zbud``. It can +also be changed at runtime using the sysfs ``zpool`` attribute, e.g.:: -echo zbud > /sys/module/zswap/parameters/zpool + echo zbud > /sys/module/zswap/parameters/zpool The zbud type zpool allocates exactly 1 page to store 2 compressed pages, which means the compression ratio will always be 2:1 or worse (because of half-full @@ -83,14 +93,16 @@ via frontswap, to free the compressed entry. Zswap seeks to be simple in its policies. Sysfs attributes allow for one user controlled policy: + * max_pool_percent - The maximum percentage of memory that the compressed - pool can occupy. + pool can occupy. -The default compressor is lzo, but it can be selected at boot time by setting -the “compressor” attribute, e.g. zswap.compressor=lzo. It can also be changed -at runtime using the sysfs "compressor" attribute, e.g. +The default compressor is lzo, but it can be selected at boot time by +setting the ``compressor`` attribute, e.g. ``zswap.compressor=lzo``. +It can also be changed at runtime using the sysfs "compressor" +attribute, e.g.:: -echo lzo > /sys/module/zswap/parameters/compressor + echo lzo > /sys/module/zswap/parameters/compressor When the zpool and/or compressor parameter is changed at runtime, any existing compressed pages are not modified; they are left in their own zpool. When a @@ -106,11 +118,12 @@ compressed length of the page is set to zero and the pattern or same-filled value is stored. Same-value filled pages identification feature is enabled by default and can be -disabled at boot time by setting the "same_filled_pages_enabled" attribute to 0, -e.g. zswap.same_filled_pages_enabled=0. It can also be enabled and disabled at -runtime using the sysfs "same_filled_pages_enabled" attribute, e.g. +disabled at boot time by setting the ``same_filled_pages_enabled`` attribute +to 0, e.g. ``zswap.same_filled_pages_enabled=0``. It can also be enabled and +disabled at runtime using the sysfs ``same_filled_pages_enabled`` +attribute, e.g.:: -echo 1 > /sys/module/zswap/parameters/same_filled_pages_enabled + echo 1 > /sys/module/zswap/parameters/same_filled_pages_enabled When zswap same-filled page identification is disabled at runtime, it will stop checking for the same-value filled pages during store operation. However, the diff --git a/Documentation/x86/intel_rdt_ui.txt b/Documentation/x86/intel_rdt_ui.txt index 71c30984e94d..a16aa2113840 100644 --- a/Documentation/x86/intel_rdt_ui.txt +++ b/Documentation/x86/intel_rdt_ui.txt @@ -17,12 +17,14 @@ MBA (Memory Bandwidth Allocation) - "mba" To use the feature mount the file system: - # mount -t resctrl resctrl [-o cdp[,cdpl2]] /sys/fs/resctrl + # mount -t resctrl resctrl [-o cdp[,cdpl2][,mba_MBps]] /sys/fs/resctrl mount options are: "cdp": Enable code/data prioritization in L3 cache allocations. "cdpl2": Enable code/data prioritization in L2 cache allocations. +"mba_MBps": Enable the MBA Software Controller(mba_sc) to specify MBA + bandwidth in MBps L2 and L3 CDP are controlled seperately. @@ -270,10 +272,11 @@ and 0xA are not. On a system with a 20-bit mask each bit represents 5% of the capacity of the cache. You could partition the cache into four equal parts with masks: 0x1f, 0x3e0, 0x7c00, 0xf8000. -Memory bandwidth(b/w) percentage --------------------------------- -For Memory b/w resource, user controls the resource by indicating the -percentage of total memory b/w. +Memory bandwidth Allocation and monitoring +------------------------------------------ + +For Memory bandwidth resource, by default the user controls the resource +by indicating the percentage of total memory bandwidth. The minimum bandwidth percentage value for each cpu model is predefined and can be looked up through "info/MB/min_bandwidth". The bandwidth @@ -285,7 +288,47 @@ to the next control step available on the hardware. The bandwidth throttling is a core specific mechanism on some of Intel SKUs. Using a high bandwidth and a low bandwidth setting on two threads sharing a core will result in both threads being throttled to use the -low bandwidth. +low bandwidth. The fact that Memory bandwidth allocation(MBA) is a core +specific mechanism where as memory bandwidth monitoring(MBM) is done at +the package level may lead to confusion when users try to apply control +via the MBA and then monitor the bandwidth to see if the controls are +effective. Below are such scenarios: + +1. User may *not* see increase in actual bandwidth when percentage + values are increased: + +This can occur when aggregate L2 external bandwidth is more than L3 +external bandwidth. Consider an SKL SKU with 24 cores on a package and +where L2 external is 10GBps (hence aggregate L2 external bandwidth is +240GBps) and L3 external bandwidth is 100GBps. Now a workload with '20 +threads, having 50% bandwidth, each consuming 5GBps' consumes the max L3 +bandwidth of 100GBps although the percentage value specified is only 50% +<< 100%. Hence increasing the bandwidth percentage will not yeild any +more bandwidth. This is because although the L2 external bandwidth still +has capacity, the L3 external bandwidth is fully used. Also note that +this would be dependent on number of cores the benchmark is run on. + +2. Same bandwidth percentage may mean different actual bandwidth + depending on # of threads: + +For the same SKU in #1, a 'single thread, with 10% bandwidth' and '4 +thread, with 10% bandwidth' can consume upto 10GBps and 40GBps although +they have same percentage bandwidth of 10%. This is simply because as +threads start using more cores in an rdtgroup, the actual bandwidth may +increase or vary although user specified bandwidth percentage is same. + +In order to mitigate this and make the interface more user friendly, +resctrl added support for specifying the bandwidth in MBps as well. The +kernel underneath would use a software feedback mechanism or a "Software +Controller(mba_sc)" which reads the actual bandwidth using MBM counters +and adjust the memowy bandwidth percentages to ensure + + "actual bandwidth < user specified bandwidth". + +By default, the schemata would take the bandwidth percentage values +where as user can switch to the "MBA software controller" mode using +a mount option 'mba_MBps'. The schemata format is specified in the below +sections. L3 schemata file details (code and data prioritization disabled) ---------------------------------------------------------------- @@ -308,13 +351,20 @@ schemata format is always: L2:<cache_id0>=<cbm>;<cache_id1>=<cbm>;... -Memory b/w Allocation details ------------------------------ +Memory bandwidth Allocation (default mode) +------------------------------------------ Memory b/w domain is L3 cache. MB:<cache_id0>=bandwidth0;<cache_id1>=bandwidth1;... +Memory bandwidth Allocation specified in MBps +--------------------------------------------- + +Memory bandwidth domain is L3 cache. + + MB:<cache_id0>=bw_MBps0;<cache_id1>=bw_MBps1;... + Reading/writing the schemata file --------------------------------- Reading the schemata file will show the state of all resources @@ -358,6 +408,15 @@ allocations can overlap or not. The allocations specifies the maximum b/w that the group may be able to use and the system admin can configure the b/w accordingly. +If the MBA is specified in MB(megabytes) then user can enter the max b/w in MB +rather than the percentage values. + +# echo "L3:0=3;1=c\nMB:0=1024;1=500" > /sys/fs/resctrl/p0/schemata +# echo "L3:0=3;1=3\nMB:0=1024;1=500" > /sys/fs/resctrl/p1/schemata + +In the above example the tasks in "p1" and "p0" on socket 0 would use a max b/w +of 1024MB where as on socket 1 they would use 500MB. + Example 2 --------- Again two sockets, but this time with a more realistic 20-bit mask. diff --git a/Documentation/x86/x86_64/boot-options.txt b/Documentation/x86/x86_64/boot-options.txt index b297c48389b9..8d109ef67ab6 100644 --- a/Documentation/x86/x86_64/boot-options.txt +++ b/Documentation/x86/x86_64/boot-options.txt @@ -187,9 +187,9 @@ PCI IOMMU (input/output memory management unit) - Currently four x86-64 PCI-DMA mapping implementations exist: + Multiple x86-64 PCI-DMA mapping implementations exist, for example: - 1. <arch/x86_64/kernel/pci-nommu.c>: use no hardware/software IOMMU at all + 1. <lib/dma-direct.c>: use no hardware/software IOMMU at all (e.g. because you have < 3 GB memory). Kernel boot message: "PCI-DMA: Disabling IOMMU" @@ -208,7 +208,7 @@ IOMMU (input/output memory management unit) Kernel boot message: "PCI-DMA: Using Calgary IOMMU" iommu=[<size>][,noagp][,off][,force][,noforce][,leak[=<nr_of_leak_pages>] - [,memaper[=<order>]][,merge][,forcesac][,fullflush][,nomerge] + [,memaper[=<order>]][,merge][,fullflush][,nomerge] [,noaperture][,calgary] General iommu options: @@ -235,14 +235,7 @@ IOMMU (input/output memory management unit) (experimental). nomerge Don't do scatter-gather (SG) merging. noaperture Ask the IOMMU not to touch the aperture for AGP. - forcesac Force single-address cycle (SAC) mode for masks <40bits - (experimental). noagp Don't initialize the AGP driver and use full aperture. - allowdac Allow double-address cycle (DAC) mode, i.e. DMA >4GB. - DAC is used with 32-bit PCI to push a 64-bit address in - two cycles. When off all DMA over >4GB is forced through - an IOMMU or software bounce buffering. - nodac Forbid DAC mode, i.e. DMA >4GB. panic Always panic when IOMMU overflows. calgary Use the Calgary IOMMU if it is available diff --git a/Documentation/x86/x86_64/mm.txt b/Documentation/x86/x86_64/mm.txt index ea91cb61a602..5432a96d31ff 100644 --- a/Documentation/x86/x86_64/mm.txt +++ b/Documentation/x86/x86_64/mm.txt @@ -20,7 +20,7 @@ ffffff0000000000 - ffffff7fffffffff (=39 bits) %esp fixup stacks ffffffef00000000 - fffffffeffffffff (=64 GB) EFI region mapping space ... unused hole ... ffffffff80000000 - ffffffff9fffffff (=512 MB) kernel text mapping, from phys 0 -ffffffffa0000000 - [fixmap start] (~1526 MB) module mapping space (variable) +ffffffffa0000000 - fffffffffeffffff (1520 MB) module mapping space [fixmap start] - ffffffffff5fffff kernel-internal fixmap range ffffffffff600000 - ffffffffff600fff (=4 kB) legacy vsyscall ABI ffffffffffe00000 - ffffffffffffffff (=2 MB) unused hole |