Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758294Ab1EMKRJ (ORCPT ); Fri, 13 May 2011 06:17:09 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:39045 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756772Ab1EMKRH (ORCPT ); Fri, 13 May 2011 06:17:07 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Message-ID: <4DCD0582.2020601@jp.fujitsu.com> Date: Fri, 13 May 2011 19:18:42 +0900 From: KOSAKI Motohiro User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; ja; rv:1.9.2.17) Gecko/20110414 Lightning/1.0b2 Thunderbird/3.1.10 MIME-Version: 1.0 To: KAMEZAWA Hiroyuki CC: CAI Qian , avagin@gmail.com, Andrey Vagin , Andrew Morton , Mel Gorman , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Minchan Kim , David Rientjes , Hugh Dickins , Oleg Nesterov Subject: Re: [PATCH 2/4] oom: kill younger process first References: <20110509182110.167F.A69D9226@jp.fujitsu.com> <20110510171335.16A7.A69D9226@jp.fujitsu.com> <20110510171641.16AF.A69D9226@jp.fujitsu.com> <20110512095243.c57e3e83.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20110512095243.c57e3e83.kamezawa.hiroyu@jp.fujitsu.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1137 Lines: 29 (2011/05/12 9:52), KAMEZAWA Hiroyuki wrote: > On Tue, 10 May 2011 17:15:01 +0900 (JST) > KOSAKI Motohiro wrote: > >> This patch introduces do_each_thread_reverse() and >> select_bad_process() uses it. The benefits are two, >> 1) oom-killer can kill younger process than older if >> they have a same oom score. Usually younger process >> is less important. 2) younger task often have PF_EXITING >> because shell script makes a lot of short lived processes. >> Reverse order search can detect it faster. >> >> Reported-by: CAI Qian >> Signed-off-by: KOSAKI Motohiro > > IIUC, for_each_thread() can be called under rcu_read_lock() but > for_each_thread_reverse() must be under tasklist_lock. > > Could you add some comment ? and prev_task() should use list_entry() > not list_entry_rcu(). Will fix. thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/