Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752272Ab0KNFV1 (ORCPT ); Sun, 14 Nov 2010 00:21:27 -0500 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:44976 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750708Ab0KNFV0 (ORCPT ); Sun, 14 Nov 2010 00:21:26 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: "Figo.zhang" Subject: Re: [PATCH v3]mm/oom-kill: direct hardware access processes should get bonus Cc: kosaki.motohiro@jp.fujitsu.com, lkml , "linux-mm@kvack.org" , Andrew Morton , "rientjes@google.com" , Linus Torvalds , "Figo.zhang" In-Reply-To: <1289402666.10699.28.camel@localhost.localdomain> References: <1289402093.10699.25.camel@localhost.localdomain> <1289402666.10699.28.camel@localhost.localdomain> Message-Id: <20101114141913.E019.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Mailer: Becky! ver. 2.50.07 [ja] Date: Sun, 14 Nov 2010 14:21:22 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2206 Lines: 58 > the victim should not directly access hardware devices like Xorg server, > because the hardware could be left in an unpredictable state, although > user-application can set /proc/pid/oom_score_adj to protect it. so i think > those processes should get bonus for protection. > > in v2, fix the incorrect comment. > in v3, change the divided the badness score by 4, like old heuristic for protection. we just > want the oom_killer don't select Root/RESOURCE/RAWIO process as possible. > > suppose that if a user process A such as email cleint "evolution" and a process B with > ditecly hareware access such as "Xorg", they have eat the equal memory (the badness score is > the same),so which process are you want to kill? so in new heuristic, it will kill the process B. > but in reality, we want to kill process A. > > Signed-off-by: Figo.zhang > Reviewed-by: KOSAKI Motohiro Sorry for the delay. I've sent completely revert patch to linus. It will disappear your headache, I believe. I'm sorry that our development caused your harm. We really don't want it. Thanks. > --- > mm/oom_kill.c | 9 +++++++++ > 1 files changed, 9 insertions(+), 0 deletions(-) > > diff --git a/mm/oom_kill.c b/mm/oom_kill.c > index 4029583..f43d759 100644 > --- a/mm/oom_kill.c > +++ b/mm/oom_kill.c > @@ -202,6 +202,15 @@ unsigned int oom_badness(struct task_struct *p, struct mem_cgroup *mem, > points -= 30; > > /* > + * Root and direct hareware access processes are usually more > + * important, so they should get bonus for protection. > + */ > + if (has_capability_noaudit(p, CAP_SYS_ADMIN) || > + has_capability_noaudit(p, CAP_SYS_RESOURCE) || > + has_capability_noaudit(p, CAP_SYS_RAWIO)) > + points /= 4; > + > + /* > * /proc/pid/oom_score_adj ranges from -1000 to +1000 such that it may > * either completely disable oom killing or always prefer a certain > * task. > > -- 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/