linux/mm/oom_kill.c, branch v3.3.5

mm: unify remaining mem_cont, mem, etc. variable names to memcg

2012-01-13T04:13:06Z

Signed-off-by: Johannes Weiner Acked-by: David Rientjes Acked-by: KAMEZAWA Hiroyuki Acked-by: Michal Hocko Cc: Balbir Singh Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: oom_kill: remove memcg argument from oom_kill_task()

2012-01-13T04:13:06Z

The memcg argument of oom_kill_task() hasn't been used since 341aea2 'oom-kill: remove boost_dying_task_prio()'. Kill it. Signed-off-by: Johannes Weiner Acked-by: David Rientjes Acked-by: KAMEZAWA Hiroyuki Acked-by: Michal Hocko Cc: Balbir Singh Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

tracepoint: add tracepoints for debugging oom_score_adj

2012-01-11T00:30:44Z

oom_score_adj is used for guarding processes from OOM-Killer. One of problem is that it's inherited at fork(). When a daemon set oom_score_adj and make children, it's hard to know where the value is set. This patch adds some tracepoints useful for debugging. This patch adds 3 trace points. - creating new task - renaming a task (exec) - set oom_score_adj To debug, users need to enable some trace pointer. Maybe filtering is useful as # EVENT=/sys/kernel/debug/tracing/events/task/ # echo "oom_score_adj != 0" > $EVENT/task_newtask/filter # echo "oom_score_adj != 0" > $EVENT/task_rename/filter # echo 1 > $EVENT/enable # EVENT=/sys/kernel/debug/tracing/events/oom/ # echo 1 > $EVENT/enable output will be like this. # grep oom /sys/kernel/debug/tracing/trace bash-7699 [007] d..3 5140.744510: oom_score_adj_update: pid=7699 comm=bash oom_score_adj=-1000 bash-7699 [007] ...1 5151.818022: task_newtask: pid=7729 comm=bash clone_flags=1200011 oom_score_adj=-1000 ls-7729 [003] ...2 5151.818504: task_rename: pid=7729 oldcomm=bash newcomm=ls oom_score_adj=-1000 bash-7699 [002] ...1 5175.701468: task_newtask: pid=7730 comm=bash clone_flags=1200011 oom_score_adj=-1000 grep-7730 [007] ...2 5175.701993: task_rename: pid=7730 oldcomm=bash newcomm=grep oom_score_adj=-1000 Signed-off-by: KAMEZAWA Hiroyuki Cc: KOSAKI Motohiro Acked-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'master' into pm-sleep

2011-12-21T20:59:45Z

* master: (848 commits) SELinux: Fix RCU deref check warning in sel_netport_insert() binary_sysctl(): fix memory leak mm/vmalloc.c: remove static declaration of va from __get_vm_area_node ipmi_watchdog: restore settings when BMC reset oom: fix integer overflow of points in oom_badness memcg: keep root group unchanged if creation fails nilfs2: potential integer overflow in nilfs_ioctl_clean_segments() nilfs2: unbreak compat ioctl cpusets: stall when updating mems_allowed for mempolicy or disjoint nodemask evm: prevent racing during tfm allocation evm: key must be set once during initialization mmc: vub300: fix type of firmware_rom_wait_states module parameter Revert "mmc: enable runtime PM by default" mmc: sdhci: remove "state" argument from sdhci_suspend_host x86, dumpstack: Fix code bytes breakage due to missing KERN_CONT IB/qib: Correct sense on freectxts increment and decrement RDMA/cma: Verify private data length cgroups: fix a css_set not found bug in cgroup_attach_proc oprofile: Fix uninitialized memory access when writing to writing to oprofilefs Revert "xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel" ... Conflicts: kernel/cgroup_freezer.c

oom: fix integer overflow of points in oom_badness

2011-12-20T18:25:04Z

An integer overflow will happen on 64bit archs if task's sum of rss, swapents and nr_ptes exceeds (2^31)/1000 value. This was introduced by commit f755a04 oom: use pte pages in OOM score where the oom score computation was divided into several steps and it's no longer computed as one expression in unsigned long(rss, swapents, nr_pte are unsigned long), where the result value assigned to points(int) is in range(1..1000). So there could be an int overflow while computing 176 points *= 1000; and points may have negative value. Meaning the oom score for a mem hog task will be one. 196 if (points <= 0) 197 return 1; For example: [ 3366] 0 3366 35390480 24303939 5 0 0 oom01 Out of memory: Kill process 3366 (oom01) score 1 or sacrifice child Here the oom1 process consumes more than 24303939(rss)*4096~=92GB physical memory, but it's oom score is one. In this situation the mem hog task is skipped and oom killer kills another and most probably innocent task with oom score greater than one. The points variable should be of type long instead of int to prevent the int overflow. Signed-off-by: Frantisek Hrbata Acked-by: KOSAKI Motohiro Acked-by: Oleg Nesterov Acked-by: David Rientjes Cc: [2.6.36+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

freezer: rename thaw_process() to __thaw_task() and simplify the implementation

2011-11-21T20:32:23Z

thaw_process() now has only internal users - system and cgroup freezers. Remove the unnecessary return value, rename, unexport and collapse __thaw_process() into it. This will help further updates to the freezer code. -v3: oom_kill grew a use of thaw_process() while this patch was pending. Convert it to use __thaw_task() for now. In the longer term, this should be handled by allowing tasks to die if killed even if it's frozen. -v2: minor style update as suggested by Matt. Signed-off-by: Tejun Heo Cc: Paul Menage Cc: Matt Helsley

oom: do not kill tasks with oom_score_adj OOM_SCORE_ADJ_MIN

2011-11-16T00:41:51Z

Commit c9f01245 ("oom: remove oom_disable_count") has removed the oom_disable_count counter which has been used for early break out from oom_badness so we could never select a task with oom_score_adj set to OOM_SCORE_ADJ_MIN (oom disabled). Now that the counter is gone we are always going through heuristics calculation and we always return a non zero positive value. This means that we can end up killing a task with OOM disabled because it is indistinguishable from regular tasks with 1% resp. CAP_SYS_ADMIN tasks with 3% usage of memory or tasks with oom_score_adj set but OOM enabled. Let's break out early if the task should have OOM disabled. Signed-off-by: Michal Hocko Acked-by: David Rientjes Acked-by: KOSAKI Motohiro Cc: Oleg Nesterov Cc: Ying Han Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

2011-11-07T03:44:47Z

* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits) Revert "tracing: Include module.h in define_trace.h" irq: don't put module.h into irq.h for tracking irqgen modules. bluetooth: macroize two small inlines to avoid module.h ip_vs.h: fix implicit use of module_get/module_put from module.h nf_conntrack.h: fix up fallout from implicit moduleparam.h presence include: replace linux/module.h with "struct module" wherever possible include: convert various register fcns to macros to avoid include chaining crypto.h: remove unused crypto_tfm_alg_modname() inline uwb.h: fix implicit use of asm/page.h for PAGE_SIZE pm_runtime.h: explicitly requires notifier.h linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h miscdevice.h: fix up implicit use of lists and types stop_machine.h: fix implicit use of smp.h for smp_processor_id of: fix implicit use of errno.h in include/linux/of.h of_platform.h: delete needless include acpi: remove module.h include from platform/aclinux.h miscdevice.h: delete unnecessary inclusion of module.h device_cgroup.h: delete needless include net: sch_generic remove redundant use of net: inet_timewait_sock doesnt need ... Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in - drivers/media/dvb/frontends/dibx000_common.c - drivers/media/video/{mt9m111.c,ov6650.c} - drivers/mfd/ab3550-core.c - include/linux/dmaengine.h

oom: fix race while temporarily setting current's oom_score_adj

2011-11-01T00:30:45Z

test_set_oom_score_adj() was introduced in 72788c385604 ("oom: replace PF_OOM_ORIGIN with toggling oom_score_adj") to temporarily elevate current's oom_score_adj for ksm and swapoff without requiring an additional per-process flag. Using that function to both set oom_score_adj to OOM_SCORE_ADJ_MAX and then reinstate the previous value is racy since it's possible that userspace can set the value to something else itself before the old value is reinstated. That results in userspace setting current's oom_score_adj to a different value and then the kernel immediately setting it back to its previous value without notification. To fix this, a new compare_swap_oom_score_adj() function is introduced with the same semantics as the compare and swap CAS instruction, or CMPXCHG on x86. It is used to reinstate the previous value of oom_score_adj if and only if the present value is the same as the old value. Signed-off-by: David Rientjes Cc: Oleg Nesterov Cc: Ying Han Cc: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

oom: remove oom_disable_count

2011-11-01T00:30:45Z

This removes mm->oom_disable_count entirely since it's unnecessary and currently buggy. The counter was intended to be per-process but it's currently decremented in the exit path for each thread that exits, causing it to underflow. The count was originally intended to prevent oom killing threads that share memory with threads that cannot be killed since it doesn't lead to future memory freeing. The counter could be fixed to represent all threads sharing the same mm, but it's better to remove the count since: - it is possible that the OOM_DISABLE thread sharing memory with the victim is waiting on that thread to exit and will actually cause future memory freeing, and - there is no guarantee that a thread is disabled from oom killing just because another thread sharing its mm is oom disabled. Signed-off-by: David Rientjes Reported-by: Oleg Nesterov Reviewed-by: Oleg Nesterov Cc: Ying Han Cc: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds