From bb29902a7515208846114b3b36a4281a9bbf766a Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Fri, 25 Mar 2016 14:20:44 -0700 Subject: [PATCH] oom, oom_reaper: protect oom_reaper_list using simpler way "oom, oom_reaper: disable oom_reaper for oom_kill_allocating_task" tried to protect oom_reaper_list using MMF_OOM_KILLED flag. But we can do it by simply checking tsk->oom_reaper_list != NULL. Signed-off-by: Tetsuo Handa Signed-off-by: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 2 -- mm/oom_kill.c | 8 ++------ 2 files changed, 2 insertions(+), 8 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 49b1febcf7c3..60bba7e032dc 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -512,8 +512,6 @@ static inline int get_dumpable(struct mm_struct *mm) #define MMF_HAS_UPROBES 19 /* has uprobes */ #define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */ -#define MMF_OOM_KILLED 21 /* OOM killer has chosen this mm */ - #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) struct sighand_struct { diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 8cc55f0f0e5c..b34d279a7ee6 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -547,7 +547,7 @@ static int oom_reaper(void *unused) static void wake_oom_reaper(struct task_struct *tsk) { - if (!oom_reaper_th) + if (!oom_reaper_th || tsk->oom_reaper_list) return; get_task_struct(tsk); @@ -681,7 +681,7 @@ void oom_kill_process(struct oom_control *oc, struct task_struct *p, unsigned int victim_points = 0; static DEFINE_RATELIMIT_STATE(oom_rs, DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST); - bool can_oom_reap; + bool can_oom_reap = true; /* * If the task is already exiting, don't alarm the sysadmin or kill @@ -743,10 +743,6 @@ void oom_kill_process(struct oom_control *oc, struct task_struct *p, /* Get a reference to safely compare mm after task_unlock(victim) */ mm = victim->mm; atomic_inc(&mm->mm_count); - - /* Make sure we do not try to oom reap the mm multiple times */ - can_oom_reap = !test_and_set_bit(MMF_OOM_KILLED, &mm->flags); - /* * We should send SIGKILL before setting TIF_MEMDIE in order to prevent * the OOM victim from depleting the memory reserves from the user