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2014-10-02Merge branch 'irqchip/atmel' into irqchip/coreJason Cooper1-1/+1
2014-10-02Merge branches 'arm/exynos', 'arm/omap', 'arm/smmu', 'x86/vt-d', 'x86/amd' and 'core' into nextJoerg Roedel1-0/+1
Conflicts: drivers/iommu/arm-smmu.c
2014-10-02Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into nextJames Morris1-1/+1
2014-10-02pinctrl: specify bindings for pins and groupsLinus Walleij1-1/+10
Pin configurations can be per-pin or per-group. Make sure that the per-group case is covered by the bindings. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-10-01net: pktgen: packet bursting via skb->xmit_moreAlexei Starovoitov1-0/+3
This patch demonstrates the effect of delaying update of HW tailptr. (based on earlier patch by Jesper) burst=1 is the default. It sends one packet with xmit_more=false burst=2 sends one packet with xmit_more=true and 2nd copy of the same packet with xmit_more=false burst=3 sends two copies of the same packet with xmit_more=true and 3rd copy with xmit_more=false Performance with ixgbe (usec 30): burst=1 tx:9.2 Mpps burst=2 tx:13.5 Mpps burst=3 tx:14.5 Mpps full 10G line rate Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-01PCI: xgene: Add APM X-Gene PCIe driverTanmay Inamdar1-0/+57
Add the AppliedMicro X-Gene SOC PCIe host controller driver. The X-Gene PCIe controller supports up to 8 lanes and GEN3 speed. The X-Gene SOC supports up to 5 PCIe ports. [bhelgaas: folded in MAINTAINERS and bindings updates] Tested-by: Ming Lei <ming.lei@canonical.com> Tested-by: Dann Frazier <dann.frazier@canonical.com> Signed-off-by: Tanmay Inamdar <tinamdar@apm.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Liviu Dudau <Liviu.Dudau@arm.com> (driver)
2014-10-01Merge branch 'pci/msi' into nextBjorn Helgaas1-0/+10
* pci/msi: PCI/MSI: Remove unnecessary temporary variable PCI/MSI: Use __write_msi_msg() instead of write_msi_msg() MSI/powerpc: Use __read_msi_msg() instead of read_msi_msg() PCI/MSI: Use __get_cached_msi_msg() instead of get_cached_msi_msg() PCI/MSI: Add "msi_bus" sysfs MSI/MSI-X control for endpoints PCI/MSI: Remove "pos" from the struct msi_desc msi_attrib PCI/MSI: Remove unused kobject from struct msi_desc PCI/MSI: Rename pci_msi_check_device() to pci_msi_supported() PCI/MSI: Move D0 check into pci_msi_check_device() PCI/MSI: Remove arch_msi_check_device() irqchip: armada-370-xp: Remove arch_msi_check_device() PCI/MSI/PPC: Remove arch_msi_check_device() Conflicts: drivers/pci/host/pcie-designware.c
2014-10-01spi: orion: support armada extended baud ratesGreg Ungerer1-1/+1
The Armada SoC family implementation of this SPI hardware module has extended the configuration register to allow for a wider range of SPI clock rates. Specifically the Serial Baud Rate Pre-selection bits in the SPI Interface Configuration Register now also use bits 6 and 7 as well. Modify the baud rate calculation to handle these differences for the Armada case. Potentially a baud rate can be setup using a number of different pre-scalar and scalar combinations. This code tries all possible pre-scalar divisors (8 in total) to try and find the most accurate set. This change introduces (and documents) a new device tree compatible device name "armada-370-spi" to support this. Signed-off-by: Greg Ungerer <gerg@uclinux.org> Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> Reviewed-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2014-10-01PCI/MSI: Add "msi_bus" sysfs MSI/MSI-X control for endpointsYijing Wang1-0/+10
The "msi_bus" sysfs file for bridges sets a bus flag to allow or disallow future driver requests for MSI or MSI-X. Previously, the sysfs file existed for endpoints but did nothing. Add "msi_bus" support for endpoints, so an administrator can prevent the use of MSI and MSI-X for individual devices. Note that as for bridges, these changes only affect future driver requests for MSI or MSI-X, so drivers may need to be reloaded. Add documentation for the "msi_bus" sysfs file. [bhelgaas: changelog, comments, add "subordinate", add endpoint printk, rework bus_flags setting, make bus_flags printk unconditional] Signed-off-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-10-01ufs: Add freq-table-hz property for UFS deviceSahitya Tummala1-6/+6
Add freq-table-hz propery for UFS device to keep track of <min max> frequencies supported by UFS clocks. Signed-off-by: Sahitya Tummala <stummala@codeaurora.org> Signed-off-by: Dolev Raviv <draviv@codeaurora.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-10-01ufs: add voting support for host controller powerRaviv Shvili1-0/+4
Add the support for voting of the regulator powering the host controller logic. Signed-off-by: Raviv Shvili <rshvili@codeaurora.org> Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org> Signed-off-by: Dolev Raviv <draviv@codeaurora.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-10-01ufs: Add clock initialization supportSujit Reddy Thumma1-1/+14
Add generic clock initialization support for UFSHCD platform driver. The clock info is read from device tree using standard clock bindings. A generic max-clock-frequency-hz property is defined to save information on maximum operating clock frequency the h/w supports. Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org> Signed-off-by: Dolev Raviv <draviv@codeaurora.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-10-01ufs: Add regulator enable supportSujit Reddy Thumma1-0/+24
UFS devices are powered by at most three external power supplies - - VCC - The flash memory core power supply, 2.7V to 3.6V or 1.70V to 1.95V - VCCQ - The controller and I/O power supply, 1.1V to 1.3V - VCCQ2 - Secondary controller and/or I/O power supply, 1.65V to 1.95V For some devices VCCQ or VCCQ2 are optional as they can be generated using internal LDO inside the UFS device. Add DT bindings for voltage regulators that can be controlled from host driver. Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org> Signed-off-by: Dolev Raviv <draviv@codeaurora.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-10-01drm/i915: Kerneldoc for intel_runtime_pm.cDaniel Vetter1-0/+12
I've decided not to document the functions exported to the audio driver since really, they shouldn't exist ... v2: Improvements from Imre's review plus a few more spelling fixes I've spotted. Reviewed-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-10-01Documentation: power: reset: Add documentation for generic SYSCON reboot driverFeng Kan1-0/+23
Add documentation for generic SYSCON reboot driver. Signed-off-by: Feng Kan <fkan@apm.com> Signed-off-by: Sebastian Reichel <sre@kernel.org>
2014-09-30doc/kernel-parameters.txt: clarify clk_ignore_unusedMike Turquette1-5/+9
Refine the definition around clk_ignore_unused, which caused some confusion recently on the linux-fbdev and linux-arm-kernel mailing lists[0]. [0] http://lkml.kernel.org/r/<20140929135358.GC30998@ulmo> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-09-30Merge branch 'topic/skl-stage1' into drm-intel-next-queuedDaniel Vetter3-1/+3
SKL stage 1 patches still need polish so will likely miss the 3.18 merge window. We've decided to postpone to 3.19 so let's pull this in to make patch merging and conflict handling easier. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2014-09-30Documentation: bindings: net: add the Marvell PXA168 Ethernet controllerAntoine Ténart1-0/+36
This adds the binding documentation for the Marvell PXA168 Ethernet controller, following its DT support. Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30Merge branch 'clk-pxa27x' into clk-nextMike Turquette1-0/+16
2014-09-30clk: dts: document pxa clock bindingRobert Jarzmik1-0/+16
Document the device-tree binding of Marvell PXA based SoCs. PXA clocks are mostly fixed rate and fixed ratio clocks derived from an external oscillator, and gated by a register set (CKEN or CKEN*). Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-09-30bcma: use chipcommon node from DT for SoC GPIO chipRafał Miłecki1-0/+12
This will allow us to define GPIO-attached devices (LEDs, buttons) in the the device tree. Signed-off-by: Rafał Miłecki <zajec5@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-09-30bcma: register bcma as device tree driverHauke Mehrtens1-0/+20
This driver is used by the bcm53xx ARM SoC code. Now it is possible to give the address of the chipcommon core in device tree and bcma will search for all the other cores. Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2014-10-01Merge commit 'v3.16' into nextJames Morris4-9/+24
2014-09-30Merge remote-tracking branches 'regulator/topic/max1586', 'regulator/topic/max77802' and 'regulator/topic/of' into regulator-nextMark Brown2-0/+81
2014-09-30Merge remote-tracking branches 'regulator/topic/drivers', 'regulator/topic/enable', 'regulator/topic/fan53555', 'regulator/topic/hi6421' and 'regulator/topic/isl9305' into regulator-nextMark Brown5-0/+104
2014-09-30Merge remote-tracking branches 'regulator/topic/as3711', 'regulator/topic/axp20x', 'regulator/topic/bcm590xx' and 'regulator/topic/da9211' into regulator-nextMark Brown1-0/+63
2014-09-30ASoC: fsl ssi doc: Remove unused propertiesFabio Estevam1-7/+1
The fsl_ssi driver only checks for the ac97 mode property, so remove the unused ones. Suggested-by: Nicolin Chen <nicoleotsuka@gmail.com> Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Acked-by: Timur Tabi <timur@tabi.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2014-09-30ASoC: ssm2602: add device tree bindingsStefan Kristiansson1-0/+19
Allow the ssm2602/ssm2603/ssm2604 codec driver to be instantiated from the device tree. Also, add Kconfig prompts to allow manual selection of both the I2C and SPI configuration versions of the driver. Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Signed-off-by: Mark Brown <broonie@kernel.org> Acked-by: Lars-Peter Clausen <lars@metafoo.de>
2014-09-30video/atmel_lcdfb: Introduce regulator supportAlexander Stein1-0/+3
This adds regulator support to enable/disable the LCD voltage, using 'lcd-supply' as regulator name. Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2014-09-30locktorture: Support rwlocksDavidlohr Bueso1-0/+5
Add a "rw_lock" torture test to stress kernel rwlocks and their irq variant. Reader critical regions are 5x longer than writers. As such a similar ratio of lock acquisitions is seen in the statistics. In the case of massive contention, both hold the lock for 1/10 of a second. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-09-29Merge tag 'for_3.18/samsung-clk' of git://git.kernel.org/pub/scm/linux/kernel/git/tfiga/samsung-clk into clk-nextMike Turquette1-1/+9
Samsung clock patches for v3.18 1) non-critical fixes (without the need to push to stable) fa0111be4ff3 clk: samsung: exynos4: remove duplicate div_core2 divider clock instantiation b511593d7165 clk: samsung: exynos4: fix g3d clocks c14254300131 clk: samsung: exynos4: add missing smmu_g2d clock and update comments 22842d244af3 clk: samsung: exynos5260: fix typo in clock name e82ba578ccde clk: samsung: exynos3250: fix width field of mout_mmc0/1 59037b92f440 clk: samsung: exynos3250: fix width and shift of div_spi0_isp clock 5ce37f266650 clk: samsung: exynos3250: fix mout_cam_blk parent list 2) Clock driver extensions 07ccf02ba5c3 dt-bindings: clk: samsung: Document the DMC domain of Exynos3250 CMU d0e73eaf1925 ARM: dts: exynos3250: Add CMU node for DMC domain clocks e3c3f19bc618 clk: samsung: exynos3250: Register DMC clk provider 4676f0aab9dc clk: samsung: exynos4: add support for MOUT_HDMI and MOUT_MIXER clocks
2014-09-30net: cpsw: Add am33xx MACID readoutMarkus Pargmann1-0/+4
This patch adds a function to get the MACIDs from the am33xx SoC control module registers which hold unique vendor MACIDs. This is only used if of_get_mac_address() fails to get a valid mac address. Signed-off-by: Markus Pargmann <mpa@pengutronix.de> Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Tested-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-30DT doc: net: cpsw mac-address is optionalMarkus Pargmann1-1/+1
mac-address is an optional property. If no mac-address is set, a random mac-address will be generated. Signed-off-by: Markus Pargmann <mpa@pengutronix.de> Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-29Merge remote-tracking branch 'regmap/topic/dt-endian' into regmap-nextMark Brown1-0/+47
2014-09-29ASoC: rt5677: Add dts properties for input/output differential configurationAnatol Pomozov1-0/+9
Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2014-09-29pinctrl: alter device tree bindings for functionsLinus Walleij1-10/+29
For function and group configuration nodes, use "function" "groups" string pairs, not "pins" where there should be "groups". Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-09-29Merge back earlier 'pm-sleep' material for v3.18.Rafael J. Wysocki1-4/+6
2014-09-29Documentation: add Device tree bindings for QCA7000Stefan Wahren1-0/+47
This patch adds the Device tree bindings for the Ethernet over SPI protocol driver of the Qualcomm QCA7000 HomePlug GreenPHY. Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-29net: tcp: add DCTCP congestion control algorithmDaniel Borkmann1-0/+43
This work adds the DataCenter TCP (DCTCP) congestion control algorithm [1], which has been first published at SIGCOMM 2010 [2], resp. follow-up analysis at SIGMETRICS 2011 [3] (and also, more recently as an informational IETF draft available at [4]). DCTCP is an enhancement to the TCP congestion control algorithm for data center networks. Typical data center workloads are i.e. i) partition/aggregate (queries; bursty, delay sensitive), ii) short messages e.g. 50KB-1MB (for coordination and control state; delay sensitive), and iii) large flows e.g. 1MB-100MB (data update; throughput sensitive). DCTCP has therefore been designed for such environments to provide/achieve the following three requirements: * High burst tolerance (incast due to partition/aggregate) * Low latency (short flows, queries) * High throughput (continuous data updates, large file transfers) with commodity, shallow buffered switches The basic idea of its design consists of two fundamentals: i) on the switch side, packets are being marked when its internal queue length > threshold K (K is chosen so that a large enough headroom for marked traffic is still available in the switch queue); ii) the sender/host side maintains a moving average of the fraction of marked packets, so each RTT, F is being updated as follows: F := X / Y, where X is # of marked ACKs, Y is total # of ACKs alpha := (1 - g) * alpha + g * F, where g is a smoothing constant The resulting alpha (iow: probability that switch queue is congested) is then being used in order to adaptively decrease the congestion window W: W := (1 - (alpha / 2)) * W The means for receiving marked packets resp. marking them on switch side in DCTCP is the use of ECN. RFC3168 describes a mechanism for using Explicit Congestion Notification from the switch for early detection of congestion, rather than waiting for segment loss to occur. However, this method only detects the presence of congestion, not the *extent*. In the presence of mild congestion, it reduces the TCP congestion window too aggressively and unnecessarily affects the throughput of long flows [4]. DCTCP, as mentioned, enhances Explicit Congestion Notification (ECN) processing to estimate the fraction of bytes that encounter congestion, rather than simply detecting that some congestion has occurred. DCTCP then scales the TCP congestion window based on this estimate [4], thus it can derive multibit feedback from the information present in the single-bit sequence of marks in its control law. And thus act in *proportion* to the extent of congestion, not its *presence*. Switches therefore set the Congestion Experienced (CE) codepoint in packets when internal queue lengths exceed threshold K. Resulting, DCTCP delivers the same or better throughput than normal TCP, while using 90% less buffer space. It was found in [2] that DCTCP enables the applications to handle 10x the current background traffic, without impacting foreground traffic. Moreover, a 10x increase in foreground traffic did not cause any timeouts, and thus largely eliminates TCP incast collapse problems. The algorithm itself has already seen deployments in large production data centers since then. We did a long-term stress-test and analysis in a data center, short summary of our TCP incast tests with iperf compared to cubic: This test measured DCTCP throughput and latency and compared it with CUBIC throughput and latency for an incast scenario. In this test, 19 senders sent at maximum rate to a single receiver. The receiver simply ran iperf -s. The senders ran iperf -c <receiver> -t 30. All senders started simultaneously (using local clocks synchronized by ntp). This test was repeated multiple times. Below shows the results from a single test. Other tests are similar. (DCTCP results were extremely consistent, CUBIC results show some variance induced by the TCP timeouts that CUBIC encountered.) For this test, we report statistics on the number of TCP timeouts, flow throughput, and traffic latency. 1) Timeouts (total over all flows, and per flow summaries): CUBIC DCTCP Total 3227 25 Mean 169.842 1.316 Median 183 1 Max 207 5 Min 123 0 Stddev 28.991 1.600 Timeout data is taken by measuring the net change in netstat -s "other TCP timeouts" reported. As a result, the timeout measurements above are not restricted to the test traffic, and we believe that it is likely that all of the "DCTCP timeouts" are actually timeouts for non-test traffic. We report them nevertheless. CUBIC will also include some non-test timeouts, but they are drawfed by bona fide test traffic timeouts for CUBIC. Clearly DCTCP does an excellent job of preventing TCP timeouts. DCTCP reduces timeouts by at least two orders of magnitude and may well have eliminated them in this scenario. 2) Throughput (per flow in Mbps): CUBIC DCTCP Mean 521.684 521.895 Median 464 523 Max 776 527 Min 403 519 Stddev 105.891 2.601 Fairness 0.962 0.999 Throughput data was simply the average throughput for each flow reported by iperf. By avoiding TCP timeouts, DCTCP is able to achieve much better per-flow results. In CUBIC, many flows experience TCP timeouts which makes flow throughput unpredictable and unfair. DCTCP, on the other hand, provides very clean predictable throughput without incurring TCP timeouts. Thus, the standard deviation of CUBIC throughput is dramatically higher than the standard deviation of DCTCP throughput. Mean throughput is nearly identical because even though cubic flows suffer TCP timeouts, other flows will step in and fill the unused bandwidth. Note that this test is something of a best case scenario for incast under CUBIC: it allows other flows to fill in for flows experiencing a timeout. Under situations where the receiver is issuing requests and then waiting for all flows to complete, flows cannot fill in for timed out flows and throughput will drop dramatically. 3) Latency (in ms): CUBIC DCTCP Mean 4.0088 0.04219 Median 4.055 0.0395 Max 4.2 0.085 Min 3.32 0.028 Stddev 0.1666 0.01064 Latency for each protocol was computed by running "ping -i 0.2 <receiver>" from a single sender to the receiver during the incast test. For DCTCP, "ping -Q 0x6 -i 0.2 <receiver>" was used to ensure that traffic traversed the DCTCP queue and was not dropped when the queue size was greater than the marking threshold. The summary statistics above are over all ping metrics measured between the single sender, receiver pair. The latency results for this test show a dramatic difference between CUBIC and DCTCP. CUBIC intentionally overflows the switch buffer which incurs the maximum queue latency (more buffer memory will lead to high latency.) DCTCP, on the other hand, deliberately attempts to keep queue occupancy low. The result is a two orders of magnitude reduction of latency with DCTCP - even with a switch with relatively little RAM. Switches with larger amounts of RAM will incur increasing amounts of latency for CUBIC, but not for DCTCP. 4) Convergence and stability test: This test measured the time that DCTCP took to fairly redistribute bandwidth when a new flow commences. It also measured DCTCP's ability to remain stable at a fair bandwidth distribution. DCTCP is compared with CUBIC for this test. At the commencement of this test, a single flow is sending at maximum rate (near 10 Gbps) to a single receiver. One second after that first flow commences, a new flow from a distinct server begins sending to the same receiver as the first flow. After the second flow has sent data for 10 seconds, the second flow is terminated. The first flow sends for an additional second. Ideally, the bandwidth would be evenly shared as soon as the second flow starts, and recover as soon as it stops. The results of this test are shown below. Note that the flow bandwidth for the two flows was measured near the same time, but not simultaneously. DCTCP performs nearly perfectly within the measurement limitations of this test: bandwidth is quickly distributed fairly between the two flows, remains stable throughout the duration of the test, and recovers quickly. CUBIC, in contrast, is slow to divide the bandwidth fairly, and has trouble remaining stable. CUBIC DCTCP Seconds Flow 1 Flow 2 Seconds Flow 1 Flow 2 0 9.93 0 0 9.92 0 0.5 9.87 0 0.5 9.86 0 1 8.73 2.25 1 6.46 4.88 1.5 7.29 2.8 1.5 4.9 4.99 2 6.96 3.1 2 4.92 4.94 2.5 6.67 3.34 2.5 4.93 5 3 6.39 3.57 3 4.92 4.99 3.5 6.24 3.75 3.5 4.94 4.74 4 6 3.94 4 5.34 4.71 4.5 5.88 4.09 4.5 4.99 4.97 5 5.27 4.98 5 4.83 5.01 5.5 4.93 5.04 5.5 4.89 4.99 6 4.9 4.99 6 4.92 5.04 6.5 4.93 5.1 6.5 4.91 4.97 7 4.28 5.8 7 4.97 4.97 7.5 4.62 4.91 7.5 4.99 4.82 8 5.05 4.45 8 5.16 4.76 8.5 5.93 4.09 8.5 4.94 4.98 9 5.73 4.2 9 4.92 5.02 9.5 5.62 4.32 9.5 4.87 5.03 10 6.12 3.2 10 4.91 5.01 10.5 6.91 3.11 10.5 4.87 5.04 11 8.48 0 11 8.49 4.94 11.5 9.87 0 11.5 9.9 0 SYN/ACK ECT test: This test demonstrates the importance of ECT on SYN and SYN-ACK packets by measuring the connection probability in the presence of competing flows for a DCTCP connection attempt *without* ECT in the SYN packet. The test was repeated five times for each number of competing flows. Competing Flows 1 | 2 | 4 | 8 | 16 ------------------------------ Mean Connection Probability 1 | 0.67 | 0.45 | 0.28 | 0 Median Connection Probability 1 | 0.65 | 0.45 | 0.25 | 0 As the number of competing flows moves beyond 1, the connection probability drops rapidly. Enabling DCTCP with this patch requires the following steps: DCTCP must be running both on the sender and receiver side in your data center, i.e.: sysctl -w net.ipv4.tcp_congestion_control=dctcp Also, ECN functionality must be enabled on all switches in your data center for DCTCP to work. The default ECN marking threshold (K) heuristic on the switch for DCTCP is e.g., 20 packets (30KB) at 1Gbps, and 65 packets (~100KB) at 10Gbps (K > 1/7 * C * RTT, [4]). In above tests, for each switch port, traffic was segregated into two queues. For any packet with a DSCP of 0x01 - or equivalently a TOS of 0x04 - the packet was placed into the DCTCP queue. All other packets were placed into the default drop-tail queue. For the DCTCP queue, RED/ECN marking was enabled, here, with a marking threshold of 75 KB. More details however, we refer you to the paper [2] under section 3). There are no code changes required to applications running in user space. DCTCP has been implemented in full *isolation* of the rest of the TCP code as its own congestion control module, so that it can run without a need to expose code to the core of the TCP stack, and thus nothing changes for non-DCTCP users. Changes in the CA framework code are minimal, and DCTCP algorithm operates on mechanisms that are already available in most Silicon. The gain (dctcp_shift_g) is currently a fixed constant (1/16) from the paper, but we leave the option that it can be chosen carefully to a different value by the user. In case DCTCP is being used and ECN support on peer site is off, DCTCP falls back after 3WHS to operate in normal TCP Reno mode. ss {-4,-6} -t -i diag interface: ... dctcp wscale:7,7 rto:203 rtt:2.349/0.026 mss:1448 cwnd:2054 ssthresh:1102 ce_state 0 alpha 15 ab_ecn 0 ab_tot 735584 send 10129.2Mbps pacing_rate 20254.1Mbps unacked:1822 retrans:0/15 reordering:101 rcv_space:29200 ... dctcp-reno wscale:7,7 rto:201 rtt:0.711/1.327 ato:40 mss:1448 cwnd:10 ssthresh:1102 fallback_mode send 162.9Mbps pacing_rate 325.5Mbps rcv_rtt:1.5 rcv_space:29200 More information about DCTCP can be found in [1-4]. [1] http://simula.stanford.edu/~alizade/Site/DCTCP.html [2] http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp-final.pdf [3] http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp_analysis-full.pdf [4] http://tools.ietf.org/html/draft-bensley-tcpm-dctcp-00 Joint work with Florian Westphal and Glenn Judd. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Glenn Judd <glenn.judd@morganstanley.com> Acked-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-28tty: serial: msm: Add earlycon supportStephen Boyd1-0/+12
Add support for DT based and command line based early console on platforms with the msm serial hardware. Cc: Rob Herring <robh@kernel.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-28serial: cadence: Add generic earlycon supportMichal Simek1-0/+6
Add earlycon support for the cadence serial port. This is based on recent patches: "tty/serial: pl011: add generic earlycon support" (sha1: 0d3c673e7881e691991b2a4745bd4f149603baa2) "tty/serial: add arm/arm64 semihosting earlycon" (sha1: d50d7269ebcb438afa346cdffce0f4e2a1b9e831) Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-29Merge tag 'renesas-clocksource-for-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas into clockevents/3.18Daniel Lezcano3-10/+48
Renesas Clocksource Updates for v3.18 * Document per-SoC bindings Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-09-29ARM: meson: documentation: Add timer documentationCarlo Caione1-0/+15
Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Carlo Caione <carlo@caione.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2014-09-28net_dma: simple removalDan Williams2-6/+8
Per commit "77873803363c net_dma: mark broken" net_dma is no longer used and there is no plan to fix it. This is the mechanical removal of bits in CONFIG_NET_DMA ifdef guards. Reverting the remainder of the net_dma induced changes is deferred to subsequent patches. Marked for stable due to Roman's report of a memory leak in dma_pin_iovec_pages(): https://lkml.org/lkml/2014/9/3/177 Cc: Dave Jiang <dave.jiang@intel.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: David Whipple <whipple@securedatainnovations.ch> Cc: Alexander Duyck <alexander.h.duyck@intel.com> Cc: <stable@vger.kernel.org> Reported-by: Roman Gushchin <klamm@yandex-team.ru> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2014-09-28Merge remote-tracking branch 'regulator/topic/sky81452' into regulator-driversMark Brown1-0/+16
Conflicts: drivers/regulator/Kconfig drivers/regulator/Makefile
2014-09-28regulator: pwm-regulator: add devicetree bindings for pwm regulatorChris Zhong1-0/+27
Document the pwm regulator Signed-off-by: Chris Zhong <zyw@rock-chips.com> Reviewed-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2014-09-28Documentation: lzo: document part of the encodingWilly Tarreau1-0/+164
Add a complete description of the LZO format as processed by the decompressor. I have not found a public specification of this format hence this analysis, which will be used to better understand the code. Cc: Willem Pinckaers <willem@lekkertech.net> Cc: "Don A. Bailey" <donb@securitymouse.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-27Merge branch 'for-3.17-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroupLinus Torvalds1-3/+3
Pull cgroup fixes from Tejun Heo: "This is quite late but these need to be backported anyway. This is the fix for a long-standing cpuset bug which existed from 2009. cpuset makes use of PF_SPREAD_{PAGE|SLAB} flags to modify the task's memory allocation behavior according to the settings of the cpuset it belongs to; unfortunately, when those flags have to be changed, cpuset did so directly even whlie the target task is running, which is obviously racy as task->flags may be modified by the task itself at any time. This obscure bug manifested as corrupt PF_USED_MATH flag leading to a weird crash. The bug is fixed by moving the flag to task->atomic_flags. The first two are prepatory ones to help defining atomic_flags accessors and the third one is the actual fix" * 'for-3.17-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cpuset: PF_SPREAD_PAGE and PF_SPREAD_SLAB should be atomic flags sched: add macros to define bitops for task atomic flags sched: fix confusing PFA_NO_NEW_PRIVS constant
2014-09-27Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-socLinus Torvalds1-2/+13
Pull ARM SoC fixes from Olof Johansson: "Here's our last set of fixes for 3.17. Most of these are for TI platforms, fixing some noisy Kconfig issues, runtime clock and power issues on several platforms and NAND timings on DRA7. There are also a couple of bug fixes for i.MX, one for QCOM and a small fix to avoid section mismatch noise on PXA. Diffstat looks large, partially due to some tables being updated and thus touching many lines. The qcom gsbi change also restructures clock management a bit and thus touches a bunch of lines. All in all, a bit more changes than we'd like at this point, but nothing stands out as risky either so it seems like the right thing to send it up now instead of holding it to the merge window" * tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: drivers/soc: qcom: do not disable the iface clock in probe ARM: imx: fix .is_enabled() of shared gate clock ARM: OMAP3: Fix I/O chain clock line assertion timed out error ARM: keystone: dts: fix bindings for pcie and usb clock nodes bus: omap_l3_noc: Fix connID for OMAP4 ARM: DT: imx53: fix lvds channel 1 port ARM: dts: cm-t54: fix serial console power supply. ARM: dts: dra7-evm: Fix NAND GPMC timings ARM: pxa: fix section mismatch warning for pxa_timer_nodt_init ARM: OMAP: Fix Kconfig warning for omap1
2014-09-27Merge tag 'sunxi-clocks-for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/mripard/linux into clk-nextMike Turquette1-0/+4
Allwinner Clocks Additions for 3.18 The most important part of this serie is the addition of the phase API to handle the MMC clocks in the Allwinner SoCs. Apart from that, the A23 gained a new mbus driver, and there's a fix for a incorrect divider table on the APB0 clock.