From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx186.postini.com [74.125.245.186]) by kanga.kvack.org (Postfix) with SMTP id F34BF6B0083 for ; Tue, 19 Jun 2012 17:39:54 -0400 (EDT) Received: by ghrr18 with SMTP id r18so6399029ghr.14 for ; Tue, 19 Jun 2012 14:39:54 -0700 (PDT) Message-ID: <4FE0F1A9.7050607@gmail.com> Date: Tue, 19 Jun 2012 17:39:53 -0400 From: KOSAKI Motohiro MIME-Version: 1.0 Subject: Re: [patch v3] mm, oom: do not schedule if current has been killed References: <4FDFDCA7.8060607@jp.fujitsu.com> <20120619135551.GA24542@redhat.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: David Rientjes Cc: Oleg Nesterov , Andrew Morton , Kamezawa Hiroyuki , KOSAKI Motohiro , linux-mm@kvack.org, kosaki.motohiro@gmail.com (6/19/12 4:58 PM), David Rientjes wrote: > The oom killer currently schedules away from current in an > uninterruptible sleep if it does not have access to memory reserves. > It's possible that current was killed because it shares memory with the > oom killed thread or because it was killed by the user in the interim, > however. > > This patch only schedules away from current if it does not have a pending > kill, i.e. if it does not share memory with the oom killed thread. It's > possible that it will immediately retry its memory allocation and fail, > but it will immediately be given access to memory reserves if it calls > the oom killer again. > > This prevents the delay of memory freeing when threads that share memory > with the oom killed thread get unnecessarily scheduled. > > Signed-off-by: David Rientjes > --- > mm/oom_kill.c | 11 +++++------ > 1 file changed, 5 insertions(+), 6 deletions(-) > > diff --git a/mm/oom_kill.c b/mm/oom_kill.c > --- a/mm/oom_kill.c > +++ b/mm/oom_kill.c > @@ -746,11 +746,11 @@ out: > read_unlock(&tasklist_lock); > > /* > - * Give "p" a good chance of killing itself before we > - * retry to allocate memory unless "p" is current > + * Give the killed threads a good chance of exiting before trying to > + * allocate memory again. > */ > - if (killed && !test_thread_flag(TIF_MEMDIE)) > - schedule_timeout_uninterruptible(1); > + if (killed) > + schedule_timeout_killable(1); > } This is not match I expected. but I have no seen a big problem. Acked-by: KOSAKI Motohiro > > /* > @@ -765,6 +765,5 @@ void pagefault_out_of_memory(void) > out_of_memory(NULL, 0, 0, NULL, false); > clear_system_oom(); > } > - if (!test_thread_flag(TIF_MEMDIE)) > - schedule_timeout_uninterruptible(1); > + schedule_timeout_killable(1); > } > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@kvack.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: email@kvack.org -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org