From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751256Ab0CYCvZ (ORCPT ); Wed, 24 Mar 2010 22:51:25 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:45380 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750772Ab0CYCvY (ORCPT ); Wed, 24 Mar 2010 22:51:24 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: Anfei Zhou Subject: Re: [PATCH] oom killer: break from infinite loop Cc: kosaki.motohiro@jp.fujitsu.com, akpm@linux-foundation.org, rientjes@google.com, nishimura@mxp.nes.nec.co.jp, kamezawa.hiroyu@jp.fujitsu.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org In-Reply-To: <1269447905-5939-1-git-send-email-anfei.zhou@gmail.com> References: <1269447905-5939-1-git-send-email-anfei.zhou@gmail.com> Message-Id: <20100325100302.9457.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.50.07 [ja] Date: Thu, 25 Mar 2010 11:51:20 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > In multi-threading environment, if the current task(A) have got > the mm->mmap_sem semaphore, and the thread(B) in the same process > is selected to be oom killed, because they shares the same semaphore, > thread B can not really be killed. So __alloc_pages_slowpath turns > to be a infinite loop. Here set all the threads in the group to > TIF_MEMDIE, it gets a chance to break and exit. > > Signed-off-by: Anfei Zhou I like this patch very much. Thanks, Anfei! Reviewed-by: KOSAKI Motohiro > --- > mm/oom_kill.c | 4 ++++ > 1 files changed, 4 insertions(+), 0 deletions(-) > > diff --git a/mm/oom_kill.c b/mm/oom_kill.c > index 9b223af..aab9892 100644 > --- a/mm/oom_kill.c > +++ b/mm/oom_kill.c > @@ -381,6 +381,8 @@ static void dump_header(struct task_struct *p, gfp_t gfp_mask, int order, > */ > static void __oom_kill_task(struct task_struct *p, int verbose) > { > + struct task_struct *t; > + > if (is_global_init(p)) { > WARN_ON(1); > printk(KERN_WARNING "tried to kill init!\n"); > @@ -412,6 +414,8 @@ static void __oom_kill_task(struct task_struct *p, int verbose) > */ > p->rt.time_slice = HZ; > set_tsk_thread_flag(p, TIF_MEMDIE); > + for (t = next_thread(p); t != p; t = next_thread(t)) > + set_tsk_thread_flag(t, TIF_MEMDIE); > > force_sig(SIGKILL, p); > } > -- > 1.6.4.rc1 > > -- > 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