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| author | KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> | 2010-08-10 18:03:00 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-08-11 08:59:19 -0700 |
| commit | 158e0a2d1b3cffed8b46cbc56393a1394672ef79 (patch) | |
| tree | a044d53137609fdfc8c1afdde366b3e205c96eda | |
| parent | 73045c47b6facbdf4656e6763c8cb469de4337e2 (diff) | |
| download | lwn-158e0a2d1b3cffed8b46cbc56393a1394672ef79.tar.gz lwn-158e0a2d1b3cffed8b46cbc56393a1394672ef79.zip | |
memcg: use find_lock_task_mm() in memory cgroups oom
When the OOM killer scans task, it check a task is under memcg or
not when it's called via memcg's context.
But, as Oleg pointed out, a thread group leader may have NULL ->mm
and task_in_mem_cgroup() may do wrong decision. We have to use
find_lock_task_mm() in memcg as generic OOM-Killer does.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/linux/oom.h | 2 | ||||
| -rw-r--r-- | mm/memcontrol.c | 10 | ||||
| -rw-r--r-- | mm/oom_kill.c | 2 |
3 files changed, 10 insertions, 4 deletions
diff --git a/include/linux/oom.h b/include/linux/oom.h index f209b683e118..5e3aa8311c5e 100644 --- a/include/linux/oom.h +++ b/include/linux/oom.h @@ -66,6 +66,8 @@ static inline void oom_killer_enable(void) extern unsigned long badness(struct task_struct *p, struct mem_cgroup *mem, const nodemask_t *nodemask, unsigned long uptime); +extern struct task_struct *find_lock_task_mm(struct task_struct *p); + /* sysctls */ extern int sysctl_oom_dump_tasks; extern int sysctl_oom_kill_allocating_task; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index ea5f5edf00b7..f52b0a1861c4 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -47,6 +47,7 @@ #include <linux/mm_inline.h> #include <linux/page_cgroup.h> #include <linux/cpu.h> +#include <linux/oom.h> #include "internal.h" #include <asm/uaccess.h> @@ -838,10 +839,13 @@ int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem) { int ret; struct mem_cgroup *curr = NULL; + struct task_struct *p; - task_lock(task); - curr = try_get_mem_cgroup_from_mm(task->mm); - task_unlock(task); + p = find_lock_task_mm(task); + if (!p) + return 0; + curr = try_get_mem_cgroup_from_mm(p->mm); + task_unlock(p); if (!curr) return 0; /* diff --git a/mm/oom_kill.c b/mm/oom_kill.c index d3def05a33d9..5014e50644d1 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -106,7 +106,7 @@ static void boost_dying_task_prio(struct task_struct *p, * pointer. Return p, or any of its subthreads with a valid ->mm, with * task_lock() held. */ -static struct task_struct *find_lock_task_mm(struct task_struct *p) +struct task_struct *find_lock_task_mm(struct task_struct *p) { struct task_struct *t = p; |