From c2419b4a4727f67af2fc2cd68b0d878b75e781bb Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Tue, 31 May 2011 10:50:10 -0400 Subject: xen: allow enable use of VGA console on dom0 Get the information about the VGA console hardware from Xen, and put it into the form the bootloader normally generates, so that the rest of the kernel can deal with VGA as usual. [ Impact: make VGA console work in dom0 ] Signed-off-by: Jeremy Fitzhardinge [v1: Rebased on 2.6.39] [v2: Removed incorrect comments and fixed compile warnings] Signed-off-by: Konrad Rzeszutek Wilk --- include/xen/interface/xen.h | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) (limited to 'include/xen') diff --git a/include/xen/interface/xen.h b/include/xen/interface/xen.h index b33257bc7e83..29b362eab6cc 100644 --- a/include/xen/interface/xen.h +++ b/include/xen/interface/xen.h @@ -449,6 +449,45 @@ struct start_info { int8_t cmd_line[MAX_GUEST_CMDLINE]; }; +struct dom0_vga_console_info { + uint8_t video_type; +#define XEN_VGATYPE_TEXT_MODE_3 0x03 +#define XEN_VGATYPE_VESA_LFB 0x23 + + union { + struct { + /* Font height, in pixels. */ + uint16_t font_height; + /* Cursor location (column, row). */ + uint16_t cursor_x, cursor_y; + /* Number of rows and columns (dimensions in characters). */ + uint16_t rows, columns; + } text_mode_3; + + struct { + /* Width and height, in pixels. */ + uint16_t width, height; + /* Bytes per scan line. */ + uint16_t bytes_per_line; + /* Bits per pixel. */ + uint16_t bits_per_pixel; + /* LFB physical address, and size (in units of 64kB). */ + uint32_t lfb_base; + uint32_t lfb_size; + /* RGB mask offsets and sizes, as defined by VBE 1.2+ */ + uint8_t red_pos, red_size; + uint8_t green_pos, green_size; + uint8_t blue_pos, blue_size; + uint8_t rsvd_pos, rsvd_size; + + /* VESA capabilities (offset 0xa, VESA command 0x4f00). */ + uint32_t gbl_caps; + /* Mode attributes (offset 0x0, VESA command 0x4f01). */ + uint16_t mode_attrs; + } vesa_lfb; + } u; +}; + /* These flags are passed in the 'flags' field of start_info_t. */ #define SIF_PRIVILEGED (1<<0) /* Is the domain privileged? */ #define SIF_INITDOMAIN (1<<1) /* Is this the initial control domain? */ -- cgit v1.2.3-59-g8ed1b From 08b8bfc1c649cf82edf43f686cbb9a4bac809679 Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Sun, 12 Jun 2011 09:21:13 -0700 Subject: xen: Add __attribute__((format(printf... where appropriate Use the compiler to verify printf formats and arguments. Fix fallout. Signed-off-by: Joe Perches Signed-off-by: Konrad Rzeszutek Wilk --- drivers/block/xen-blkback/xenbus.c | 2 +- include/xen/hvc-console.h | 4 +++- include/xen/xenbus.h | 2 ++ 3 files changed, 6 insertions(+), 2 deletions(-) (limited to 'include/xen') diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index 6cc0db1bf522..3f129b45451a 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -684,7 +684,7 @@ again: err = xenbus_switch_state(dev, XenbusStateConnected); if (err) - xenbus_dev_fatal(dev, err, "switching to Connected state", + xenbus_dev_fatal(dev, err, "%s: switching to Connected state", dev->nodename); return; diff --git a/include/xen/hvc-console.h b/include/xen/hvc-console.h index c3adde32669b..901724dc528d 100644 --- a/include/xen/hvc-console.h +++ b/include/xen/hvc-console.h @@ -6,11 +6,13 @@ extern struct console xenboot_console; #ifdef CONFIG_HVC_XEN void xen_console_resume(void); void xen_raw_console_write(const char *str); +__attribute__((format(printf, 1, 2))) void xen_raw_printk(const char *fmt, ...); #else static inline void xen_console_resume(void) { } static inline void xen_raw_console_write(const char *str) { } -static inline void xen_raw_printk(const char *fmt, ...) { } +static inline __attribute__((format(printf, 1, 2))) +void xen_raw_printk(const char *fmt, ...) { } #endif #endif /* XEN_HVC_CONSOLE_H */ diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h index 5467369e0889..aceeca799fd7 100644 --- a/include/xen/xenbus.h +++ b/include/xen/xenbus.h @@ -223,7 +223,9 @@ int xenbus_free_evtchn(struct xenbus_device *dev, int port); enum xenbus_state xenbus_read_driver_state(const char *path); +__attribute__((format(printf, 3, 4))) void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...); +__attribute__((format(printf, 3, 4))) void xenbus_dev_fatal(struct xenbus_device *dev, int err, const char *fmt, ...); const char *xenbus_strstate(enum xenbus_state state); -- cgit v1.2.3-59-g8ed1b From a50777c791031d7345ce95785ea6220f67339d90 Mon Sep 17 00:00:00 2001 From: Dan Magenheimer Date: Fri, 8 Jul 2011 12:26:21 -0600 Subject: xen: tmem: self-ballooning and frontswap-selfshrinking This patch introduces two in-kernel drivers for Xen transcendent memory ("tmem") functionality that complement cleancache and frontswap. Both use control theory to dynamically adjust and optimize memory utilization. Selfballooning controls the in-kernel Xen balloon driver, targeting a goal value (vm_committed_as), thus pushing less frequently used clean page cache pages (through the cleancache code) into Xen tmem where Xen can balance needs across all VMs residing on the physical machine. Frontswap-selfshrinking controls the number of pages in frontswap, driving it towards zero (effectively doing a partial swapoff) when in-kernel memory pressure subsides, freeing up RAM for other VMs. More detail is provided in the header comment of xen-selfballooning.c. Signed-off-by: Dan Magenheimer [v8: konrad.wilk@oracle.com: set default enablement depending on frontswap] [v7: konrad.wilk@oracle.com: fix capitalization and punctuation in comments] [v6: fix frontswap-selfshrinking initialization] [v6: konrad.wilk@oracle.com: fix init pr_infos; add comments about swap] [v5: konrad.wilk@oracle.com: add NULL to attr list; move inits up to decls] [v4: dkiper@net-space.pl: use strict_strtoul plus a few syntactic nits] [v3: konrad.wilk@oracle.com: fix potential divides-by-zero] [v3: konrad.wilk@oracle.com: add many more comments, fix nits] [v2: rebased to linux-3.0-rc1] [v2: Ian.Campbell@citrix.com: reorganize as new file (xen-selfballoon.c)] [v2: dkiper@net-space.pl: proper access to vm_committed_as] [v2: dkiper@net-space.pl: accounting fixes] Cc: Jan Beulich Cc: Jeremy Fitzhardinge Cc: --- drivers/xen/Kconfig | 17 ++ drivers/xen/Makefile | 1 + drivers/xen/xen-balloon.c | 2 + drivers/xen/xen-selfballoon.c | 485 ++++++++++++++++++++++++++++++++++++++++++ include/xen/balloon.h | 10 + include/xen/tmem.h | 5 + 6 files changed, 520 insertions(+) create mode 100644 drivers/xen/xen-selfballoon.c create mode 100644 include/xen/tmem.h (limited to 'include/xen') diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig index a59638b37c1a..fd3266696a4d 100644 --- a/drivers/xen/Kconfig +++ b/drivers/xen/Kconfig @@ -9,6 +9,23 @@ config XEN_BALLOON the system to expand the domain's memory allocation, or alternatively return unneeded memory to the system. +config XEN_SELFBALLOONING + bool "Dynamically self-balloon kernel memory to target" + depends on XEN && XEN_BALLOON && CLEANCACHE && SWAP + default n + help + Self-ballooning dynamically balloons available kernel memory driven + by the current usage of anonymous memory ("committed AS") and + controlled by various sysfs-settable parameters. Configuring + FRONTSWAP is highly recommended; if it is not configured, self- + ballooning is disabled by default but can be enabled with the + 'selfballooning' kernel boot parameter. If FRONTSWAP is configured, + frontswap-selfshrinking is enabled by default but can be disabled + with the 'noselfshrink' kernel boot parameter; and self-ballooning + is enabled by default but can be disabled with the 'noselfballooning' + kernel boot parameter. Note that systems without a sufficiently + large swap device should not enable self-ballooning. + config XEN_SCRUB_PAGES bool "Scrub pages before returning them to system" depends on XEN_BALLOON diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile index bbc18258ecc5..458057464dd1 100644 --- a/drivers/xen/Makefile +++ b/drivers/xen/Makefile @@ -9,6 +9,7 @@ obj-$(CONFIG_BLOCK) += biomerge.o obj-$(CONFIG_HOTPLUG_CPU) += cpu_hotplug.o obj-$(CONFIG_XEN_XENCOMM) += xencomm.o obj-$(CONFIG_XEN_BALLOON) += xen-balloon.o +obj-$(CONFIG_XEN_SELFBALLOONING) += xen-selfballoon.o obj-$(CONFIG_XEN_DEV_EVTCHN) += xen-evtchn.o obj-$(CONFIG_XEN_GNTDEV) += xen-gntdev.o obj-$(CONFIG_XEN_GRANT_DEV_ALLOC) += xen-gntalloc.o diff --git a/drivers/xen/xen-balloon.c b/drivers/xen/xen-balloon.c index a4ff225ee868..5c9dc43c1e94 100644 --- a/drivers/xen/xen-balloon.c +++ b/drivers/xen/xen-balloon.c @@ -98,6 +98,8 @@ static int __init balloon_init(void) register_balloon(&balloon_sysdev); + register_xen_selfballooning(&balloon_sysdev); + target_watch.callback = watch_target; xenstore_notifier.notifier_call = balloon_init_watcher; diff --git a/drivers/xen/xen-selfballoon.c b/drivers/xen/xen-selfballoon.c new file mode 100644 index 000000000000..010937b5a7c9 --- /dev/null +++ b/drivers/xen/xen-selfballoon.c @@ -0,0 +1,485 @@ +/****************************************************************************** + * Xen selfballoon driver (and optional frontswap self-shrinking driver) + * + * Copyright (c) 2009-2011, Dan Magenheimer, Oracle Corp. + * + * This code complements the cleancache and frontswap patchsets to optimize + * support for Xen Transcendent Memory ("tmem"). The policy it implements + * is rudimentary and will likely improve over time, but it does work well + * enough today. + * + * Two functionalities are implemented here which both use "control theory" + * (feedback) to optimize memory utilization. In a virtualized environment + * such as Xen, RAM is often a scarce resource and we would like to ensure + * that each of a possibly large number of virtual machines is using RAM + * efficiently, i.e. using as little as possible when under light load + * and obtaining as much as possible when memory demands are high. + * Since RAM needs vary highly dynamically and sometimes dramatically, + * "hysteresis" is used, that is, memory target is determined not just + * on current data but also on past data stored in the system. + * + * "Selfballooning" creates memory pressure by managing the Xen balloon + * driver to decrease and increase available kernel memory, driven + * largely by the target value of "Committed_AS" (see /proc/meminfo). + * Since Committed_AS does not account for clean mapped pages (i.e. pages + * in RAM that are identical to pages on disk), selfballooning has the + * affect of pushing less frequently used clean pagecache pages out of + * kernel RAM and, presumably using cleancache, into Xen tmem where + * Xen can more efficiently optimize RAM utilization for such pages. + * + * When kernel memory demand unexpectedly increases faster than Xen, via + * the selfballoon driver, is able to (or chooses to) provide usable RAM, + * the kernel may invoke swapping. In most cases, frontswap is able + * to absorb this swapping into Xen tmem. However, due to the fact + * that the kernel swap subsystem assumes swapping occurs to a disk, + * swapped pages may sit on the disk for a very long time; even if + * the kernel knows the page will never be used again. This is because + * the disk space costs very little and can be overwritten when + * necessary. When such stale pages are in frontswap, however, they + * are taking up valuable real estate. "Frontswap selfshrinking" works + * to resolve this: When frontswap activity is otherwise stable + * and the guest kernel is not under memory pressure, the "frontswap + * selfshrinking" accounts for this by providing pressure to remove some + * pages from frontswap and return them to kernel memory. + * + * For both "selfballooning" and "frontswap-selfshrinking", a worker + * thread is used and sysfs tunables are provided to adjust the frequency + * and rate of adjustments to achieve the goal, as well as to disable one + * or both functions independently. + * + * While some argue that this functionality can and should be implemented + * in userspace, it has been observed that bad things happen (e.g. OOMs). + * + * System configuration note: Selfballooning should not be enabled on + * systems without a sufficiently large swap device configured; for best + * results, it is recommended that total swap be increased by the size + * of the guest memory. Also, while technically not required to be + * configured, it is highly recommended that frontswap also be configured + * and enabled when selfballooning is running. So, selfballooning + * is disabled by default if frontswap is not configured and can only + * be enabled with the "selfballooning" kernel boot option; similarly + * selfballooning is enabled by default if frontswap is configured and + * can be disabled with the "noselfballooning" kernel boot option. Finally, + * when frontswap is configured, frontswap-selfshrinking can be disabled + * with the "noselfshrink" kernel boot option. + * + * Selfballooning is disallowed in domain0 and force-disabled. + * + */ + +#include +#include +#include + +#include + +#include + +/* Enable/disable with sysfs. */ +static int xen_selfballooning_enabled __read_mostly; + +/* + * Controls rate at which memory target (this iteration) approaches + * ultimate goal when memory need is increasing (up-hysteresis) or + * decreasing (down-hysteresis). Higher values of hysteresis cause + * slower increases/decreases. The default values for the various + * parameters were deemed reasonable by experimentation, may be + * workload-dependent, and can all be adjusted via sysfs. + */ +static unsigned int selfballoon_downhysteresis __read_mostly = 8; +static unsigned int selfballoon_uphysteresis __read_mostly = 1; + +/* In HZ, controls frequency of worker invocation. */ +static unsigned int selfballoon_interval __read_mostly = 5; + +static void selfballoon_process(struct work_struct *work); +static DECLARE_DELAYED_WORK(selfballoon_worker, selfballoon_process); + +#ifdef CONFIG_FRONTSWAP +#include + +/* Enable/disable with sysfs. */ +static bool frontswap_selfshrinking __read_mostly; + +/* Enable/disable with kernel boot option. */ +static bool use_frontswap_selfshrink __initdata = true; + +/* + * The default values for the following parameters were deemed reasonable + * by experimentation, may be workload-dependent, and can all be + * adjusted via sysfs. + */ + +/* Control rate for frontswap shrinking. Higher hysteresis is slower. */ +static unsigned int frontswap_hysteresis __read_mostly = 20; + +/* + * Number of selfballoon worker invocations to wait before observing that + * frontswap selfshrinking should commence. Note that selfshrinking does + * not use a separate worker thread. + */ +static unsigned int frontswap_inertia __read_mostly = 3; + +/* Countdown to next invocation of frontswap_shrink() */ +static unsigned long frontswap_inertia_counter; + +/* + * Invoked by the selfballoon worker thread, uses current number of pages + * in frontswap (frontswap_curr_pages()), previous status, and control + * values (hysteresis and inertia) to determine if frontswap should be + * shrunk and what the new frontswap size should be. Note that + * frontswap_shrink is essentially a partial swapoff that immediately + * transfers pages from the "swap device" (frontswap) back into kernel + * RAM; despite the name, frontswap "shrinking" is very different from + * the "shrinker" interface used by the kernel MM subsystem to reclaim + * memory. + */ +static void frontswap_selfshrink(void) +{ + static unsigned long cur_frontswap_pages; + static unsigned long last_frontswap_pages; + static unsigned long tgt_frontswap_pages; + + last_frontswap_pages = cur_frontswap_pages; + cur_frontswap_pages = frontswap_curr_pages(); + if (!cur_frontswap_pages || + (cur_frontswap_pages > last_frontswap_pages)) { + frontswap_inertia_counter = frontswap_inertia; + return; + } + if (frontswap_inertia_counter && --frontswap_inertia_counter) + return; + if (cur_frontswap_pages <= frontswap_hysteresis) + tgt_frontswap_pages = 0; + else + tgt_frontswap_pages = cur_frontswap_pages - + (cur_frontswap_pages / frontswap_hysteresis); + frontswap_shrink(tgt_frontswap_pages); +} + +static int __init xen_nofrontswap_selfshrink_setup(char *s) +{ + use_frontswap_selfshrink = false; + return 1; +} + +__setup("noselfshrink", xen_nofrontswap_selfshrink_setup); + +/* Disable with kernel boot option. */ +static bool use_selfballooning __initdata = true; + +static int __init xen_noselfballooning_setup(char *s) +{ + use_selfballooning = false; + return 1; +} + +__setup("noselfballooning", xen_noselfballooning_setup); +#else /* !CONFIG_FRONTSWAP */ +/* Enable with kernel boot option. */ +static bool use_selfballooning __initdata = false; + +static int __init xen_selfballooning_setup(char *s) +{ + use_selfballooning = true; + return 1; +} + +__setup("selfballooning", xen_selfballooning_setup); +#endif /* CONFIG_FRONTSWAP */ + +/* + * Use current balloon size, the goal (vm_committed_as), and hysteresis + * parameters to set a new target balloon size + */ +static void selfballoon_process(struct work_struct *work) +{ + unsigned long cur_pages, goal_pages, tgt_pages; + bool reset_timer = false; + + if (xen_selfballooning_enabled) { + cur_pages = balloon_stats.current_pages; + tgt_pages = cur_pages; /* default is no change */ + goal_pages = percpu_counter_read_positive(&vm_committed_as) + + balloon_stats.current_pages - totalram_pages; +#ifdef CONFIG_FRONTSWAP + /* allow space for frontswap pages to be repatriated */ + if (frontswap_selfshrinking && frontswap_enabled) + goal_pages += frontswap_curr_pages(); +#endif + if (cur_pages > goal_pages) + tgt_pages = cur_pages - + ((cur_pages - goal_pages) / + selfballoon_downhysteresis); + else if (cur_pages < goal_pages) + tgt_pages = cur_pages + + ((goal_pages - cur_pages) / + selfballoon_uphysteresis); + /* else if cur_pages == goal_pages, no change */ + balloon_set_new_target(tgt_pages); + reset_timer = true; + } +#ifdef CONFIG_FRONTSWAP + if (frontswap_selfshrinking && frontswap_enabled) { + frontswap_selfshrink(); + reset_timer = true; + } +#endif + if (reset_timer) + schedule_delayed_work(&selfballoon_worker, + selfballoon_interval * HZ); +} + +#ifdef CONFIG_SYSFS + +#include +#include + +#define SELFBALLOON_SHOW(name, format, args...) \ + static ssize_t show_##name(struct sys_device *dev, \ + struct sysdev_attribute *attr, \ + char *buf) \ + { \ + return sprintf(buf, format, ##args); \ + } + +SELFBALLOON_SHOW(selfballooning, "%d\n", xen_selfballooning_enabled); + +static ssize_t store_selfballooning(struct sys_device *dev, + struct sysdev_attribute *attr, + const char *buf, + size_t count) +{ + bool was_enabled = xen_selfballooning_enabled; + unsigned long tmp; + int err; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + err = strict_strtoul(buf, 10, &tmp); + if (err || ((tmp != 0) && (tmp != 1))) + return -EINVAL; + + xen_selfballooning_enabled = !!tmp; + if (!was_enabled && xen_selfballooning_enabled) + schedule_delayed_work(&selfballoon_worker, + selfballoon_interval * HZ); + + return count; +} + +static SYSDEV_ATTR(selfballooning, S_IRUGO | S_IWUSR, + show_selfballooning, store_selfballooning); + +SELFBALLOON_SHOW(selfballoon_interval, "%d\n", selfballoon_interval); + +static ssize_t store_selfballoon_interval(struct sys_device *dev, + struct sysdev_attribute *attr, + const char *buf, + size_t count) +{ + unsigned long val; + int err; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + err = strict_strtoul(buf, 10, &val); + if (err || val == 0) + return -EINVAL; + selfballoon_interval = val; + return count; +} + +static SYSDEV_ATTR(selfballoon_interval, S_IRUGO | S_IWUSR, + show_selfballoon_interval, store_selfballoon_interval); + +SELFBALLOON_SHOW(selfballoon_downhys, "%d\n", selfballoon_downhysteresis); + +static ssize_t store_selfballoon_downhys(struct sys_device *dev, + struct sysdev_attribute *attr, + const char *buf, + size_t count) +{ + unsigned long val; + int err; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + err = strict_strtoul(buf, 10, &val); + if (err || val == 0) + return -EINVAL; + selfballoon_downhysteresis = val; + return count; +} + +static SYSDEV_ATTR(selfballoon_downhysteresis, S_IRUGO | S_IWUSR, + show_selfballoon_downhys, store_selfballoon_downhys); + + +SELFBALLOON_SHOW(selfballoon_uphys, "%d\n", selfballoon_uphysteresis); + +static ssize_t store_selfballoon_uphys(struct sys_device *dev, + struct sysdev_attribute *attr, + const char *buf, + size_t count) +{ + unsigned long val; + int err; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + err = strict_strtoul(buf, 10, &val); + if (err || val == 0) + return -EINVAL; + selfballoon_uphysteresis = val; + return count; +} + +static SYSDEV_ATTR(selfballoon_uphysteresis, S_IRUGO | S_IWUSR, + show_selfballoon_uphys, store_selfballoon_uphys); + +#ifdef CONFIG_FRONTSWAP +SELFBALLOON_SHOW(frontswap_selfshrinking, "%d\n", frontswap_selfshrinking); + +static ssize_t store_frontswap_selfshrinking(struct sys_device *dev, + struct sysdev_attribute *attr, + const char *buf, + size_t count) +{ + bool was_enabled = frontswap_selfshrinking; + unsigned long tmp; + int err; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + err = strict_strtoul(buf, 10, &tmp); + if (err || ((tmp != 0) && (tmp != 1))) + return -EINVAL; + frontswap_selfshrinking = !!tmp; + if (!was_enabled && !xen_selfballooning_enabled && + frontswap_selfshrinking) + schedule_delayed_work(&selfballoon_worker, + selfballoon_interval * HZ); + + return count; +} + +static SYSDEV_ATTR(frontswap_selfshrinking, S_IRUGO | S_IWUSR, + show_frontswap_selfshrinking, store_frontswap_selfshrinking); + +SELFBALLOON_SHOW(frontswap_inertia, "%d\n", frontswap_inertia); + +static ssize_t store_frontswap_inertia(struct sys_device *dev, + struct sysdev_attribute *attr, + const char *buf, + size_t count) +{ + unsigned long val; + int err; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + err = strict_strtoul(buf, 10, &val); + if (err || val == 0) + return -EINVAL; + frontswap_inertia = val; + frontswap_inertia_counter = val; + return count; +} + +static SYSDEV_ATTR(frontswap_inertia, S_IRUGO | S_IWUSR, + show_frontswap_inertia, store_frontswap_inertia); + +SELFBALLOON_SHOW(frontswap_hysteresis, "%d\n", frontswap_hysteresis); + +static ssize_t store_frontswap_hysteresis(struct sys_device *dev, + struct sysdev_attribute *attr, + const char *buf, + size_t count) +{ + unsigned long val; + int err; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + err = strict_strtoul(buf, 10, &val); + if (err || val == 0) + return -EINVAL; + frontswap_hysteresis = val; + return count; +} + +static SYSDEV_ATTR(frontswap_hysteresis, S_IRUGO | S_IWUSR, + show_frontswap_hysteresis, store_frontswap_hysteresis); + +#endif /* CONFIG_FRONTSWAP */ + +static struct attribute *selfballoon_attrs[] = { + &attr_selfballooning.attr, + &attr_selfballoon_interval.attr, + &attr_selfballoon_downhysteresis.attr, + &attr_selfballoon_uphysteresis.attr, +#ifdef CONFIG_FRONTSWAP + &attr_frontswap_selfshrinking.attr, + &attr_frontswap_hysteresis.attr, + &attr_frontswap_inertia.attr, +#endif + NULL +}; + +static struct attribute_group selfballoon_group = { + .name = "selfballoon", + .attrs = selfballoon_attrs +}; +#endif + +int register_xen_selfballooning(struct sys_device *sysdev) +{ + int error = -1; + +#ifdef CONFIG_SYSFS + error = sysfs_create_group(&sysdev->kobj, &selfballoon_group); +#endif + return error; +} +EXPORT_SYMBOL(register_xen_selfballooning); + +static int __init xen_selfballoon_init(void) +{ + bool enable = false; + + if (!xen_domain()) + return -ENODEV; + + if (xen_initial_domain()) { + pr_info("xen/balloon: Xen selfballooning driver " + "disabled for domain0.\n"); + return -ENODEV; + } + + xen_selfballooning_enabled = tmem_enabled && use_selfballooning; + if (xen_selfballooning_enabled) { + pr_info("xen/balloon: Initializing Xen " + "selfballooning driver.\n"); + enable = true; + } +#ifdef CONFIG_FRONTSWAP + frontswap_selfshrinking = tmem_enabled && use_frontswap_selfshrink; + if (frontswap_selfshrinking) { + pr_info("xen/balloon: Initializing frontswap " + "selfshrinking driver.\n"); + enable = true; + } +#endif + if (!enable) + return -ENODEV; + + schedule_delayed_work(&selfballoon_worker, selfballoon_interval * HZ); + + return 0; +} + +subsys_initcall(xen_selfballoon_init); + +MODULE_LICENSE("GPL"); diff --git a/include/xen/balloon.h b/include/xen/balloon.h index a2b22f01a51d..4076ed72afbd 100644 --- a/include/xen/balloon.h +++ b/include/xen/balloon.h @@ -23,3 +23,13 @@ void balloon_set_new_target(unsigned long target); int alloc_xenballooned_pages(int nr_pages, struct page** pages); void free_xenballooned_pages(int nr_pages, struct page** pages); + +struct sys_device; +#ifdef CONFIG_XEN_SELFBALLOONING +extern int register_xen_selfballooning(struct sys_device *sysdev); +#else +static inline int register_xen_selfballooning(struct sys_device *sysdev) +{ + return -ENOSYS; +} +#endif diff --git a/include/xen/tmem.h b/include/xen/tmem.h new file mode 100644 index 000000000000..82e2c83a32f5 --- /dev/null +++ b/include/xen/tmem.h @@ -0,0 +1,5 @@ +#ifndef _XEN_TMEM_H +#define _XEN_TMEM_H +/* defined in drivers/xen/tmem.c */ +extern int tmem_enabled; +#endif /* _XEN_TMEM_H */ -- cgit v1.2.3-59-g8ed1b