From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755108Ab0FNAgT (ORCPT ); Sun, 13 Jun 2010 20:36:19 -0400 Received: from mx1.redhat.com ([209.132.183.28]:32033 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755002Ab0FNAgS (ORCPT ); Sun, 13 Jun 2010 20:36:18 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Roland McGrath To: Oleg Nesterov X-Fcc: ~/Mail/linus Cc: KOSAKI Motohiro , LKML , linux-mm , David Rientjes , Andrew Morton , KAMEZAWA Hiroyuki , Nick Piggin Subject: Re: [PATCH] oom: Make coredump interruptible In-Reply-To: Oleg Nesterov's message of Sunday, 13 June 2010 17:53:54 +0200 <20100613155354.GA8428@redhat.com> References: <20100604112721.GA12582@redhat.com> <20100609195309.GA6899@redhat.com> <20100613175547.616F.A69D9226@jp.fujitsu.com> <20100613155354.GA8428@redhat.com> X-Windows: graphics hacking :: Roman numerals : sqrt (pi) Message-Id: <20100614003601.0FB21408C1@magilla.sf.frob.com> Date: Sun, 13 Jun 2010 17:36:00 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > 1) back to implement signal->oom_victim > > because We are using SIGKILL for OOM and struct signal > > naturally represent signal target. > > Yes, but if this process participates in the coredump, we should find > the right thread, or mark mm or mm->core_state. > > In fact, I was never sure that oom-kill should kill the single process. > Perhaps it should kill all tasks using the same ->mm instead. But this > is another story. Indeed. But as long as oom_kill acts on process granularity, I don't think we should have it set an mm-granularity flag. That calculus changes if a core dump is actually in progress, since that is already definitely going to kill all tasks using that mm. When no dump is in progress, it feels wrong to leave any state change in mm, since the other mm-sharers were not affected. Thanks, Roland From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id CE2E96B01AF for ; Sun, 13 Jun 2010 20:36:07 -0400 (EDT) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Roland McGrath Subject: Re: [PATCH] oom: Make coredump interruptible In-Reply-To: Oleg Nesterov's message of Sunday, 13 June 2010 17:53:54 +0200 <20100613155354.GA8428@redhat.com> References: <20100604112721.GA12582@redhat.com> <20100609195309.GA6899@redhat.com> <20100613175547.616F.A69D9226@jp.fujitsu.com> <20100613155354.GA8428@redhat.com> Message-Id: <20100614003601.0FB21408C1@magilla.sf.frob.com> Date: Sun, 13 Jun 2010 17:36:00 -0700 (PDT) Sender: owner-linux-mm@kvack.org To: Oleg Nesterov Cc: KOSAKI Motohiro , LKML , linux-mm , David Rientjes , Andrew Morton , KAMEZAWA Hiroyuki , Nick Piggin List-ID: > > 1) back to implement signal->oom_victim > > because We are using SIGKILL for OOM and struct signal > > naturally represent signal target. > > Yes, but if this process participates in the coredump, we should find > the right thread, or mark mm or mm->core_state. > > In fact, I was never sure that oom-kill should kill the single process. > Perhaps it should kill all tasks using the same ->mm instead. But this > is another story. Indeed. But as long as oom_kill acts on process granularity, I don't think we should have it set an mm-granularity flag. That calculus changes if a core dump is actually in progress, since that is already definitely going to kill all tasks using that mm. When no dump is in progress, it feels wrong to leave any state change in mm, since the other mm-sharers were not affected. Thanks, Roland -- 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