From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f69.google.com (mail-pg0-f69.google.com [74.125.83.69]) by kanga.kvack.org (Postfix) with ESMTP id 303706B0003 for ; Tue, 20 Mar 2018 07:57:56 -0400 (EDT) Received: by mail-pg0-f69.google.com with SMTP id w23so771214pgv.17 for ; Tue, 20 Mar 2018 04:57:56 -0700 (PDT) Received: from www262.sakura.ne.jp (www262.sakura.ne.jp. [202.181.97.72]) by mx.google.com with ESMTPS id p1si1040170pfb.188.2018.03.20.04.57.54 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 20 Mar 2018 04:57:54 -0700 (PDT) From: Tetsuo Handa Subject: [PATCH 2/2] mm,oom_reaper: Correct MAX_OOM_REAP_RETRIES'th attempt. Date: Tue, 20 Mar 2018 20:57:56 +0900 Message-Id: <1521547076-3399-2-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> In-Reply-To: <1521547076-3399-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> References: <1521547076-3399-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org Cc: Tetsuo Handa , David Rientjes , Michal Hocko I got "oom_reaper: unable to reap pid:" messages when the victim thread was blocked inside free_pgtables() (which occurred after returning from unmap_vmas() and setting MMF_OOM_SKIP). We don't need to complain when __oom_reap_task_mm() returned true (by e.g. finding MMF_OOM_SKIP already set) when oom_reap_task() was trying MAX_OOM_REAP_RETRIES'th attempt. [ 663.593821] Killed process 7558 (a.out) total-vm:4176kB, anon-rss:84kB, file-rss:0kB, shmem-rss:0kB [ 664.684801] oom_reaper: unable to reap pid:7558 (a.out) [ 664.892292] a.out D13272 7558 6931 0x00100084 [ 664.895765] Call Trace: [ 664.897574] ? __schedule+0x25f/0x780 [ 664.900099] schedule+0x2d/0x80 [ 664.902260] rwsem_down_write_failed+0x2bb/0x440 [ 664.905249] ? rwsem_down_write_failed+0x55/0x440 [ 664.908335] ? free_pgd_range+0x569/0x5e0 [ 664.911145] call_rwsem_down_write_failed+0x13/0x20 [ 664.914121] down_write+0x49/0x60 [ 664.916519] ? unlink_file_vma+0x28/0x50 [ 664.919255] unlink_file_vma+0x28/0x50 [ 664.922234] free_pgtables+0x36/0x100 [ 664.924797] exit_mmap+0xbb/0x180 [ 664.927220] mmput+0x50/0x110 [ 664.929504] copy_process.part.41+0xb61/0x1fe0 [ 664.932448] ? _do_fork+0xe6/0x560 [ 664.934902] ? _do_fork+0xe6/0x560 [ 664.937361] _do_fork+0xe6/0x560 [ 664.939742] ? syscall_trace_enter+0x1a9/0x240 [ 664.942693] ? retint_user+0x18/0x18 [ 664.945309] ? page_fault+0x2f/0x50 [ 664.947896] ? trace_hardirqs_on_caller+0x11f/0x1b0 [ 664.951075] do_syscall_64+0x74/0x230 [ 664.953747] entry_SYSCALL_64_after_hwframe+0x42/0xb7 Signed-off-by: Tetsuo Handa Cc: Michal Hocko Cc: David Rientjes --- mm/oom_kill.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 900300c..1cb2b98 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -588,11 +588,11 @@ static void oom_reap_task(struct task_struct *tsk) struct mm_struct *mm = tsk->signal->oom_mm; /* Retry the down_read_trylock(mmap_sem) a few times */ - while (attempts++ < MAX_OOM_REAP_RETRIES && !__oom_reap_task_mm(tsk, mm)) + while (attempts++ < MAX_OOM_REAP_RETRIES) { + if (__oom_reap_task_mm(tsk, mm)) + goto done; schedule_timeout_idle(HZ/10); - - if (attempts <= MAX_OOM_REAP_RETRIES) - goto done; + } pr_info("oom_reaper: unable to reap pid:%d (%s)\n", -- 1.8.3.1