From 1e6f1e335e5df63c90e6f8f8a4681159e2657e7c Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Wed, 10 Feb 2016 10:12:33 +1100 Subject: [PATCH] mm, oom_reaper: report success/failure Inform about the successful/failed oom_reaper attempts and dump all the held locks to tell us more who is blocking the progress. Signed-off-by: Michal Hocko Cc: Andrea Argangeli Cc: David Rientjes Cc: Hugh Dickins Cc: Johannes Weiner Cc: Mel Gorman Cc: Oleg Nesterov Cc: Rik van Riel Cc: Tetsuo Handa Signed-off-by: Andrew Morton --- mm/oom_kill.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index fc3a17689746..2a8fb4dd7245 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -423,6 +423,7 @@ static struct task_struct *oom_reaper_th; static struct task_struct *task_to_reap; static DECLARE_WAIT_QUEUE_HEAD(oom_reaper_wait); +#define K(x) ((x) << (PAGE_SHIFT-10)) static bool __oom_reap_task(struct task_struct *tsk) { struct mmu_gather tlb; @@ -479,6 +480,11 @@ static bool __oom_reap_task(struct task_struct *tsk) } } tlb_finish_mmu(&tlb, 0, -1); + pr_info("oom_reaper: reaped process :%d (%s) anon-rss:%lukB, file-rss:%lukB, shmem-rss:%lulB\n", + task_pid_nr(tsk), tsk->comm, + K(get_mm_counter(mm, MM_ANONPAGES)), + K(get_mm_counter(mm, MM_FILEPAGES)), + K(get_mm_counter(mm, MM_SHMEMPAGES))); up_read(&mm->mmap_sem); /* @@ -495,14 +501,21 @@ out: return ret; } +#define MAX_OOM_REAP_RETRIES 10 static void oom_reap_task(struct task_struct *tsk) { int attempts = 0; /* Retry the down_read_trylock(mmap_sem) a few times */ - while (attempts++ < 10 && !__oom_reap_task(tsk)) + while (attempts++ < MAX_OOM_REAP_RETRIES && !__oom_reap_task(tsk)) schedule_timeout_idle(HZ/10); + if (attempts > MAX_OOM_REAP_RETRIES) { + pr_info("oom_reaper: unable to reap pid:%d (%s)\n", + task_pid_nr(tsk), tsk->comm); + debug_show_all_locks(); + } + /* Drop a reference taken by wake_oom_reaper */ put_task_struct(tsk); } @@ -653,7 +666,6 @@ static bool process_shares_mm(struct task_struct *p, struct mm_struct *mm) return false; } -#define K(x) ((x) << (PAGE_SHIFT-10)) /* * Must be called while holding a reference to p, which will be released upon * returning. -- 2.39.5