From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755151Ab3IIPbK (ORCPT ); Mon, 9 Sep 2013 11:31:10 -0400 Received: from mail-lb0-f170.google.com ([209.85.217.170]:37674 "EHLO mail-lb0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755106Ab3IIPbH (ORCPT ); Mon, 9 Sep 2013 11:31:07 -0400 From: Sergey Dyasly To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, Andrew Morton , David Rientjes , Michal Hocko , Rusty Russell , Sha Zhengju , Oleg Nesterov , Sergey Dyasly Subject: [PATCH] OOM killer: wait for tasks with pending SIGKILL to exit Date: Mon, 9 Sep 2013 19:30:24 +0400 Message-Id: <1378740624-2456-1-git-send-email-dserrg@gmail.com> X-Mailer: git-send-email 1.8.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If OOM killer finds a task which is about to exit or is already doing so, there is no need to kill anyone. It should just wait until task dies. Add missing fatal_signal_pending() check and allow selected task to use memory reserves in order to exit quickly. Also remove redundant PF_EXITING check after victim has been selected. Signed-off-by: Sergey Dyasly --- mm/oom_kill.c | 17 +++++------------ 1 file changed, 5 insertions(+), 12 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 98e75f2..ef83b81 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -275,13 +275,16 @@ enum oom_scan_t oom_scan_process_thread(struct task_struct *task, if (oom_task_origin(task)) return OOM_SCAN_SELECT; - if (task->flags & PF_EXITING && !force_kill) { + if ((task->flags & PF_EXITING || fatal_signal_pending(task)) && + !force_kill) { /* * If this task is not being ptraced on exit, then wait for it * to finish before killing some other task unnecessarily. */ - if (!(task->group_leader->ptrace & PT_TRACE_EXIT)) + if (!(task->group_leader->ptrace & PT_TRACE_EXIT)) { + set_tsk_thread_flag(task, TIF_MEMDIE); return OOM_SCAN_ABORT; + } } return OOM_SCAN_OK; } @@ -412,16 +415,6 @@ void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order, static DEFINE_RATELIMIT_STATE(oom_rs, DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST); - /* - * If the task is already exiting, don't alarm the sysadmin or kill - * its children or threads, just set TIF_MEMDIE so it can die quickly - */ - if (p->flags & PF_EXITING) { - set_tsk_thread_flag(p, TIF_MEMDIE); - put_task_struct(p); - return; - } - if (__ratelimit(&oom_rs)) dump_header(p, gfp_mask, order, memcg, nodemask); -- 1.8.1.2