- 10 8月, 2010 15 次提交
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由 David Rientjes 提交于
Remove the redundancy in __oom_kill_task() since: - init can never be passed to this function: it will never be PF_EXITING or selectable from select_bad_process(), and - it will never be passed a task from oom_kill_task() without an ->mm and we're unconcerned about detachment from exiting tasks, there's no reason to protect them against SIGKILL or access to memory reserves. Also moves the kernel log message to a higher level since the verbosity is not always emitted here; we need not print an error message if an exiting task is given a longer timeslice. __oom_kill_task() only has a single caller, so it can be merged into that function at the same time. Signed-off-by: NDavid Rientjes <rientjes@google.com> Reviewed-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
It is possible to remove the special pagefault oom handler by simply oom locking all system zones and then calling directly into out_of_memory(). All populated zones must have ZONE_OOM_LOCKED set, otherwise there is a parallel oom killing in progress that will lead to eventual memory freeing so it's not necessary to needlessly kill another task. The context in which the pagefault is allocating memory is unknown to the oom killer, so this is done on a system-wide level. If a task has already been oom killed and hasn't fully exited yet, this will be a no-op since select_bad_process() recognizes tasks across the system with TIF_MEMDIE set. Signed-off-by: NDavid Rientjes <rientjes@google.com> Acked-by: NNick Piggin <npiggin@suse.de> Acked-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
There are various points in the oom killer where the kernel must determine whether to panic or not. It's better to extract this to a helper function to remove all the confusion as to its semantics. Also fix a call to dump_header() where tasklist_lock is not read- locked, as required. There's no functional change with this patch. Acked-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NDavid Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
The oom killer tasklist dump, enabled with the oom_dump_tasks sysctl, is very helpful information in diagnosing why a user's task has been killed. It emits useful information such as each eligible thread's memory usage that can determine why the system is oom, so it should be enabled by default. Signed-off-by: NDavid Rientjes <rientjes@google.com> Acked-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
The oom killer presently kills current whenever there is no more memory free or reclaimable on its mempolicy's nodes. There is no guarantee that current is a memory-hogging task or that killing it will free any substantial amount of memory, however. In such situations, it is better to scan the tasklist for nodes that are allowed to allocate on current's set of nodes and kill the task with the highest badness() score. This ensures that the most memory-hogging task, or the one configured by the user with /proc/pid/oom_adj, is always selected in such scenarios. Signed-off-by: NDavid Rientjes <rientjes@google.com> Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
When a task is chosen for oom kill, the oom killer first attempts to sacrifice a child not sharing its parent's memory instead. Unfortunately, this often kills in a seemingly random fashion based on the ordering of the selected task's child list. Additionally, it is not guaranteed at all to free a large amount of memory that we need to prevent additional oom killing in the very near future. Instead, we now only attempt to sacrifice the worst child not sharing its parent's memory, if one exists. The worst child is indicated with the highest badness() score. This serves two advantages: we kill a memory-hogging task more often, and we allow the configurable /proc/pid/oom_adj value to be considered as a factor in which child to kill. Reviewers may observe that the previous implementation would iterate through the children and attempt to kill each until one was successful and then the parent if none were found while the new code simply kills the most memory-hogging task or the parent. Note that the only time oom_kill_task() fails, however, is when a child does not have an mm or has a /proc/pid/oom_adj of OOM_DISABLE. badness() returns 0 for both cases, so the final oom_kill_task() will always succeed. Signed-off-by: NDavid Rientjes <rientjes@google.com> Acked-by: NRik van Riel <riel@redhat.com> Acked-by: NNick Piggin <npiggin@suse.de> Acked-by: NBalbir Singh <balbir@linux.vnet.ibm.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
Tasks that do not share the same set of allowed nodes with the task that triggered the oom should not be considered as candidates for oom kill. Tasks in other cpusets with a disjoint set of mems would be unfairly penalized otherwise because of oom conditions elsewhere; an extreme example could unfairly kill all other applications on the system if a single task in a user's cpuset sets itself to OOM_DISABLE and then uses more memory than allowed. Killing tasks outside of current's cpuset rarely would free memory for current anyway. To use a sane heuristic, we must ensure that killing a task would likely free memory for current and avoid needlessly killing others at all costs just because their potential memory freeing is unknown. It is better to kill current than another task needlessly. Signed-off-by: NDavid Rientjes <rientjes@google.com> Acked-by: NRik van Riel <riel@redhat.com> Acked-by: NNick Piggin <npiggin@suse.de> Acked-by: NBalbir Singh <balbir@linux.vnet.ibm.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
It's unnecessary to SIGKILL a task that is already PF_EXITING and can actually cause a NULL pointer dereference of the sighand if it has already been detached. Instead, simply set TIF_MEMDIE so it has access to memory reserves and can quickly exit as the comment implies. Reviewed-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: NDavid Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
It's possible to livelock the page allocator if a thread has mm->mmap_sem and fails to make forward progress because the oom killer selects another thread sharing the same ->mm to kill that cannot exit until the semaphore is dropped. The oom killer will not kill multiple tasks at the same time; each oom killed task must exit before another task may be killed. Thus, if one thread is holding mm->mmap_sem and cannot allocate memory, all threads sharing the same ->mm are blocked from exiting as well. In the oom kill case, that means the thread holding mm->mmap_sem will never free additional memory since it cannot get access to memory reserves and the thread that depends on it with access to memory reserves cannot exit because it cannot acquire the semaphore. Thus, the page allocators livelocks. When the oom killer is called and current happens to have a pending SIGKILL, this patch automatically gives it access to memory reserves and returns. Upon returning to the page allocator, its allocation will hopefully succeed so it can quickly exit and free its memory. If not, the page allocator will fail the allocation if it is not __GFP_NOFAIL. Reviewed-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: NDavid Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
When find_lock_task_mm() returns a thread other than p in dump_tasks(), its name should be displayed instead. This is the thread that will be targeted by the oom killer, not its mm-less parent. This also allows us to safely dereference task->comm without needing get_task_comm(). While we're here, remove the cast on task_cpu(task) as Andrew suggested. Signed-off-by: NDavid Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
The comments in dump_tasks() should be updated to be more clear about why tasks are filtered and how they are filtered by its argument. An unnecessary comment concerning a check for is_global_init() is removed since it isn't of importance. Suggested-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NDavid Rientjes <rientjes@google.com> Acked-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 KOSAKI Motohiro 提交于
dump_task() should use find_lock_task_mm() too. It is necessary for protecting task-exiting race. dump_tasks() currently filters any task that does not have an attached ->mm since it incorrectly assumes that it must either be in the process of exiting and has detached its memory or that it's a kernel thread; multithreaded tasks may actually have subthreads that have a valid ->mm pointer and thus those threads should actually be displayed. This change finds those threads, if they exist, and emit their information along with the rest of the candidate tasks for kill. Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NDavid Rientjes <rientjes@google.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Oleg Nesterov 提交于
Almost all ->mm == NULL checks in oom_kill.c are wrong. The current code assumes that the task without ->mm has already released its memory and ignores the process. However this is not necessarily true when this process is multithreaded, other live sub-threads can use this ->mm. - Remove the "if (!p->mm)" check in select_bad_process(), it is just wrong. - Add the new helper, find_lock_task_mm(), which finds the live thread which uses the memory and takes task_lock() to pin ->mm - change oom_badness() to use this helper instead of just checking ->mm != NULL. - As David pointed out, select_bad_process() must never choose the task without ->mm, but no matter what oom_badness() returns the task can be chosen if nothing else has been found yet. Change oom_badness() to return int, change it to return -1 if find_lock_task_mm() fails, and change select_bad_process() to check points >= 0. Note! This patch is not enough, we need more changes. - oom_badness() was fixed, but oom_kill_task() still ignores the task without ->mm - oom_forkbomb_penalty() should use find_lock_task_mm() too, and it also needs other changes to actually find the first first-descendant children This will be addressed later. [kosaki.motohiro@jp.fujitsu.com: use in badness(), __oom_kill_task()] Signed-off-by: NOleg Nesterov <oleg@redhat.com> Signed-off-by: NDavid Rientjes <rientjes@google.com> Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Oleg Nesterov 提交于
select_bad_process() checks PF_EXITING to detect the task which is going to release its memory, but the logic is very wrong. - a single process P with the dead group leader disables select_bad_process() completely, it will always return ERR_PTR() while P can live forever - if the PF_EXITING task has already released its ->mm it doesn't make sense to expect it is goiing to free more memory (except task_struct/etc) Change the code to ignore the PF_EXITING tasks without ->mm. Signed-off-by: NOleg Nesterov <oleg@redhat.com> Signed-off-by: NDavid Rientjes <rientjes@google.com> Cc: Balbir Singh <balbir@in.ibm.com> Acked-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Oleg Nesterov 提交于
select_bad_process() thinks a kernel thread can't have ->mm != NULL, this is not true due to use_mm(). Change the code to check PF_KTHREAD. Reviewed-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: NOleg Nesterov <oleg@redhat.com> Signed-off-by: NDavid Rientjes <rientjes@google.com> Acked-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 28 5月, 2010 1 次提交
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由 David Rientjes 提交于
It's pointless to try to kill current if select_bad_process() did not find an eligible task to kill in mem_cgroup_out_of_memory() since it's guaranteed that current is a member of the memcg that is oom and it is, by definition, unkillable. Signed-off-by: NDavid Rientjes <rientjes@google.com> Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 30 3月, 2010 1 次提交
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由 Tejun Heo 提交于
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: NTejun Heo <tj@kernel.org> Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
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- 13 3月, 2010 2 次提交
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由 KAMEZAWA Hiroyuki 提交于
In current page-fault code, handle_mm_fault() -> ... -> mem_cgroup_charge() -> map page or handle error. -> check return code. If page fault's return code is VM_FAULT_OOM, page_fault_out_of_memory() is called. But if it's caused by memcg, OOM should have been already invoked. Then, I added a patch: a636b327. That patch records last_oom_jiffies for memcg's sub-hierarchy and prevents page_fault_out_of_memory from being invoked in near future. But Nishimura-san reported that check by jiffies is not enough when the system is terribly heavy. This patch changes memcg's oom logic as. * If memcg causes OOM-kill, continue to retry. * remove jiffies check which is used now. * add memcg-oom-lock which works like perzone oom lock. * If current is killed(as a process), bypass charge. Something more sophisticated can be added but this pactch does fundamental things. TODO: - add oom notifier - add permemcg disable-oom-kill flag and freezer at oom. - more chances for wake up oom waiter (when changing memory limit etc..) Reviewed-by: NDaisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Tested-by: NDaisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: NDaisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 KAMEZAWA Hiroyuki 提交于
Presently, if panic_on_oom=2, the whole system panics even if the oom happend in some special situation (as cpuset, mempolicy....). Then, panic_on_oom=2 means painc_on_oom_always. Now, memcg doesn't check panic_on_oom flag. This patch adds a check. BTW, how it's useful ? kdump+panic_on_oom=2 is the last tool to investigate what happens in oom-ed system. When a task is killed, the sysytem recovers and there will be few hint to know what happnes. In mission critical system, oom should never happen. Then, panic_on_oom=2+kdump is useful to avoid next OOM by knowing precise information via snapshot. TODO: - For memcg, it's for isolate system's memory usage, oom-notiifer and freeze_at_oom (or rest_at_oom) should be implemented. Then, management daemon can do similar jobs (as kdump) or taking snapshot per cgroup. Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: David Rientjes <rientjes@google.com> Cc: Nick Piggin <npiggin@suse.de> Reviewed-by: NDaisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 07 3月, 2010 1 次提交
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由 KAMEZAWA Hiroyuki 提交于
Presently, per-mm statistics counter is defined by macro in sched.h This patch modifies it to - defined in mm.h as inlinf functions - use array instead of macro's name creation. This patch is for reducing patch size in future patch to modify implementation of per-mm counter. Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: NMinchan Kim <minchan.kim@gmail.com> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 23 2月, 2010 1 次提交
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由 KAMEZAWA Hiroyuki 提交于
Presently the oom-killer is memcg aware and it finds the worst process from processes under memcg(s) in oom. Then, it kills victim's child first. It may kill a child in another cgroup and may not be any help for recovery. And it will break the assumption users have. This patch fixes it. Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: NMinchan Kim <minchan.kim@gmail.com> Cc: Balbir Singh <balbir@linux.vnet.ibm.com> Reviewed-by: NDaisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Acked-by: NDavid Rientjes <rientjes@google.com> Cc: <stable@kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 16 12月, 2009 4 次提交
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由 Daisuke Nishimura 提交于
task_in_mem_cgroup(), which is called by select_bad_process() to check whether a task can be a candidate for being oom-killed from memcg's limit, checks "curr->use_hierarchy"("curr" is the mem_cgroup the task belongs to). But this check return true(it's false positive) when: <some path>/aa use_hierarchy == 0 <- hitting limit <some path>/aa/00 use_hierarchy == 1 <- the task belongs to This leads to killing an innocent task in aa/00. This patch is a fix for this bug. And this patch also fixes the arg for mem_cgroup_print_oom_info(). We should print information of mem_cgroup which the task being killed, not current, belongs to. Signed-off-by: NDaisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Acked-by: NBalbir Singh <balbir@linux.vnet.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 KAMEZAWA Hiroyuki 提交于
Fix node-oriented allocation handling in oom-kill.c I myself think of this as a bugfix not as an ehnancement. In these days, things are changed as - alloc_pages() eats nodemask as its arguments, __alloc_pages_nodemask(). - mempolicy don't maintain its own private zonelists. (And cpuset doesn't use nodemask for __alloc_pages_nodemask()) So, current oom-killer's check function is wrong. This patch does - check nodemask, if nodemask && nodemask doesn't cover all node_states[N_HIGH_MEMORY], this is CONSTRAINT_MEMORY_POLICY. - Scan all zonelist under nodemask, if it hits cpuset's wall this faiulre is from cpuset. And - modifies the caller of out_of_memory not to call oom if __GFP_THISNODE. This doesn't change "current" behavior. If callers use __GFP_THISNODE it should handle "page allocation failure" by itself. - handle __GFP_NOFAIL+__GFP_THISNODE path. This is something like a FIXME but this gfpmask is not used now. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hioryu@jp.fujitsu.com> Acked-by: NDavid Rientjes <rientjes@google.com> Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 KOSAKI Motohiro 提交于
In a typical oom analysis scenario, we frequently want to know whether the killed process has a memory leak or not at the first step. This patch adds vsz and rss information to the oom log to help this analysis. To save time for the debugging. example: =================================================================== rsyslogd invoked oom-killer: gfp_mask=0x201da, order=0, oom_adj=0 Pid: 1308, comm: rsyslogd Not tainted 2.6.32-rc6 #24 Call Trace: [<ffffffff8132e35b>] ?_spin_unlock+0x2b/0x40 [<ffffffff810f186e>] oom_kill_process+0xbe/0x2b0 (snip) 492283 pages non-shared Out of memory: kill process 2341 (memhog) score 527276 or a child Killed process 2341 (memhog) vsz:1054552kB, anon-rss:970588kB, file-rss:4kB =========================================================================== ^ | here [rientjes@google.com: fix race, add pid & comm to message] Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NDavid Rientjes <rientjes@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
The oom killer header, including information such as the allocation order and gfp mask, current's cpuset and memory controller, call trace, and VM state information is currently only shown when the oom killer has selected a task to kill. This information is omitted, however, when the oom killer panics either because of panic_on_oom sysctl settings or when no killable task was found. It is still relevant to know crucial pieces of information such as the allocation order and VM state when diagnosing such issues, especially at boot. This patch displays the oom killer header whenever it panics so that bug reports can include pertinent information to debug the issue, if possible. Signed-off-by: NDavid Rientjes <rientjes@google.com> Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 22 9月, 2009 4 次提交
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由 KOSAKI Motohiro 提交于
Current oom_kill doesn't only kill the victim process, but also kill all thas shread the same mm. it mean vfork parent will be killed. This is definitely incorrect. another process have another oom_adj. we shouldn't ignore their oom_adj (it might have OOM_DISABLE). following caller hit the minefield. =============================== switch (constraint) { case CONSTRAINT_MEMORY_POLICY: oom_kill_process(current, gfp_mask, order, 0, NULL, "No available memory (MPOL_BIND)"); break; Note: force_sig(SIGKILL) send SIGKILL to all thread in the process. We don't need to care multi thread in here. Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Paul Menage <menage@google.com> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 KOSAKI Motohiro 提交于
oom-killer kills a process, not task. Then oom_score should be calculated as per-process too. it makes consistency more and makes speed up select_bad_process(). Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Paul Menage <menage@google.com> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 KOSAKI Motohiro 提交于
Currently, OOM logic callflow is here. __out_of_memory() select_bad_process() for each task badness() calculate badness of one task oom_kill_process() search child oom_kill_task() kill target task and mm shared tasks with it example, process-A have two thread, thread-A and thread-B and it have very fat memory and each thread have following oom_adj and oom_score. thread-A: oom_adj = OOM_DISABLE, oom_score = 0 thread-B: oom_adj = 0, oom_score = very-high Then, select_bad_process() select thread-B, but oom_kill_task() refuse kill the task because thread-A have OOM_DISABLE. Thus __out_of_memory() call select_bad_process() again. but select_bad_process() select the same task. It mean kernel fall in livelock. The fact is, select_bad_process() must select killable task. otherwise OOM logic go into livelock. And root cause is, oom_adj shouldn't be per-thread value. it should be per-process value because OOM-killer kill a process, not thread. Thus This patch moves oomkilladj (now more appropriately named oom_adj) from struct task_struct to struct signal_struct. it naturally prevent select_bad_process() choose wrong task. Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Paul Menage <menage@google.com> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Hugh Dickins 提交于
Just as the swapoff system call allocates many pages of RAM to various processes, perhaps triggering OOM, so "echo 2 >/sys/kernel/mm/ksm/run" (unmerge) is liable to allocate many pages of RAM to various processes, perhaps triggering OOM; and each is normally run from a modest admin process (swapoff or shell), easily repeated until it succeeds. So treat unmerge_and_remove_all_rmap_items() in the same way that we treat try_to_unuse(): generalize PF_SWAPOFF to PF_OOM_ORIGIN, and bracket both with that, to ask the OOM killer to kill them first, to prevent them from spawning more and more OOM kills. Signed-off-by: NHugh Dickins <hugh.dickins@tiscali.co.uk> Acked-by: NIzik Eidus <ieidus@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 19 8月, 2009 1 次提交
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由 KOSAKI Motohiro 提交于
The commit 2ff05b2b (oom: move oom_adj value) moveed the oom_adj value to the mm_struct. It was a very good first step for sanitize OOM. However Paul Menage reported the commit makes regression to his job scheduler. Current OOM logic can kill OOM_DISABLED process. Why? His program has the code of similar to the following. ... set_oom_adj(OOM_DISABLE); /* The job scheduler never killed by oom */ ... if (vfork() == 0) { set_oom_adj(0); /* Invoked child can be killed */ execve("foo-bar-cmd"); } .... vfork() parent and child are shared the same mm_struct. then above set_oom_adj(0) doesn't only change oom_adj for vfork() child, it's also change oom_adj for vfork() parent. Then, vfork() parent (job scheduler) lost OOM immune and it was killed. Actually, fork-setting-exec idiom is very frequently used in userland program. We must not break this assumption. Then, this patch revert commit 2ff05b2b and related commit. Reverted commit list --------------------- - commit 2ff05b2b (oom: move oom_adj value from task_struct to mm_struct) - commit 4d8b9135 (oom: avoid unnecessary mm locking and scanning for OOM_DISABLE) - commit 81236810 (oom: only oom kill exiting tasks with attached memory) - commit 933b787b (mm: copy over oom_adj value at fork time) Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Paul Menage <menage@google.com> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Nick Piggin <npiggin@suse.de> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 17 6月, 2009 3 次提交
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由 David Rientjes 提交于
When a task is chosen for oom kill and is found to be PF_EXITING, __oom_kill_task() is called to elevate the task's timeslice and give it access to memory reserves so that it may quickly exit. This privilege is unnecessary, however, if the task has already detached its mm. Although its possible for the mm to become detached later since task_lock() is not held, __oom_kill_task() will simply be a no-op in such circumstances. Subsequently, it is no longer necessary to warn about killing mm-less tasks since it is a no-op. Signed-off-by: NDavid Rientjes <rientjes@google.com> Acked-by: NRik van Riel <riel@redhat.com> Cc: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: Minchan Kim <minchan.kim@gmail.com> Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
This moves the check for OOM_DISABLE to the badness heuristic so it is only necessary to hold task_lock() once. If the mm is OOM_DISABLE, the score is 0, which is also correctly exported via /proc/pid/oom_score. This requires that tasks with badness scores of 0 are prohibited from being oom killed, which makes sense since they would not allow for future memory freeing anyway. Since the oom_adj value is a characteristic of an mm and not a task, it is no longer necessary to check the oom_adj value for threads sharing the same memory (except when simply issuing SIGKILLs for threads in other thread groups). Cc: Nick Piggin <npiggin@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: NDavid Rientjes <rientjes@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 David Rientjes 提交于
The per-task oom_adj value is a characteristic of its mm more than the task itself since it's not possible to oom kill any thread that shares the mm. If a task were to be killed while attached to an mm that could not be freed because another thread were set to OOM_DISABLE, it would have needlessly been terminated since there is no potential for future memory freeing. This patch moves oomkilladj (now more appropriately named oom_adj) from struct task_struct to struct mm_struct. This requires task_lock() on a task to check its oom_adj value to protect against exec, but it's already necessary to take the lock when dereferencing the mm to find the total VM size for the badness heuristic. This fixes a livelock if the oom killer chooses a task and another thread sharing the same memory has an oom_adj value of OOM_DISABLE. This occurs because oom_kill_task() repeatedly returns 1 and refuses to kill the chosen task while select_bad_process() will repeatedly choose the same task during the next retry. Taking task_lock() in select_bad_process() to check for OOM_DISABLE and in oom_kill_task() to check for threads sharing the same memory will be removed in the next patch in this series where it will no longer be necessary. Writing to /proc/pid/oom_adj for a kthread will now return -EINVAL since these threads are immune from oom killing already. They simply report an oom_adj value of OOM_DISABLE. Cc: Nick Piggin <npiggin@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mel@csn.ul.ie> Signed-off-by: NDavid Rientjes <rientjes@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 29 5月, 2009 1 次提交
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由 David Rientjes 提交于
When /proc/sys/vm/oom_dump_tasks is enabled, it is possible to get a NULL pointer for tasks that have detached mm's since task_lock() is not held during the tasklist scan. Add the task_lock(). Acked-by: NNick Piggin <npiggin@suse.de> Acked-by: NMel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: NDavid Rientjes <rientjes@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 07 5月, 2009 1 次提交
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由 David Rientjes 提交于
When /proc/sys/vm/oom_kill_allocating_task is set for large systems that want to avoid the lengthy tasklist scan, it's possible to livelock if current is ineligible for oom kill. This normally happens when it is set to OOM_DISABLE, but is also possible if any threads are sharing the same ->mm with a different tgid. So change __out_of_memory() to fall back to the full task-list scan if it was unable to kill `current'. Cc: Nick Piggin <npiggin@suse.de> Signed-off-by: NDavid Rientjes <rientjes@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 03 4月, 2009 1 次提交
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由 Balbir Singh 提交于
Add RSS and swap to OOM output from memcg Display memcg values like failcnt, usage and limit when an OOM occurs due to memcg. Thanks to Johannes Weiner, Li Zefan, David Rientjes, Kamezawa Hiroyuki, Daisuke Nishimura and KOSAKI Motohiro for review. Sample output ------------- Task in /a/x killed as a result of limit of /a memory: usage 1048576kB, limit 1048576kB, failcnt 4183 memory+swap: usage 1400964akB, limit 9007199254740991kB, failcnt 0 [akpm@linux-foundation.org: compilation fix] [akpm@linux-foundation.org: fix kerneldoc and whitespace] [akpm@linux-foundation.org: add printk facility level] Signed-off-by: NBalbir Singh <balbir@linux.vnet.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Paul Menage <menage@google.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 01 4月, 2009 1 次提交
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由 Cyrill Gorcunov 提交于
There is no need to call for int_sqrt if argument is 0. Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Christoph Lameter <cl@linux-foundation.org> Acked-by: NDavid Rientjes <rientjes@google.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 09 1月, 2009 2 次提交
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由 Daisuke Nishimura 提交于
mpol_rebind_mm(), which can be called from cpuset_attach(), does down_write(mm->mmap_sem). This means down_write(mm->mmap_sem) can be called under cgroup_mutex. OTOH, page fault path does down_read(mm->mmap_sem) and calls mem_cgroup_try_charge_xxx(), which may eventually calls mem_cgroup_out_of_memory(). And mem_cgroup_out_of_memory() calls cgroup_lock(). This means cgroup_lock() can be called under down_read(mm->mmap_sem). If those two paths race, deadlock can happen. This patch avoid this deadlock by: - remove cgroup_lock() from mem_cgroup_out_of_memory(). - define new mutex (memcg_tasklist) and serialize mem_cgroup_move_task() (->attach handler of memory cgroup) and mem_cgroup_out_of_memory. Signed-off-by: NDaisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Reviewed-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: NBalbir Singh <balbir@linux.vnet.ibm.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 KAMEZAWA Hiroyuki 提交于
Current mmtom has new oom function as pagefault_out_of_memory(). It's added for select bad process rathar than killing current. When memcg hit limit and calls OOM at page_fault, this handler called and system-wide-oom handling happens. (means kernel panics if panic_on_oom is true....) To avoid overkill, check memcg's recent behavior before starting system-wide-oom. And this patch also fixes to guarantee "don't accnout against process with TIF_MEMDIE". This is necessary for smooth OOM. [akpm@linux-foundation.org: build fix] Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Cc: Badari Pulavarty <pbadari@us.ibm.com> Cc: Jan Blunck <jblunck@suse.de> Cc: Hirokazu Takahashi <taka@valinux.co.jp> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 07 1月, 2009 1 次提交
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由 David Rientjes 提交于
When cpusets are enabled, it's necessary to print the triggering task's set of allowable nodes so the subsequently printed meminfo can be interpreted correctly. We also print the task's cpuset name for informational purposes. [rientjes@google.com: task lock current before dereferencing cpuset] Cc: Paul Menage <menage@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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