From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f172.google.com (mail-pd0-f172.google.com [209.85.192.172]) by kanga.kvack.org (Postfix) with ESMTP id 706F36B0032 for ; Tue, 23 Dec 2014 07:52:30 -0500 (EST) Received: by mail-pd0-f172.google.com with SMTP id y13so7776951pdi.31 for ; Tue, 23 Dec 2014 04:52:30 -0800 (PST) Received: from www262.sakura.ne.jp (www262.sakura.ne.jp. [2001:e42:101:1:202:181:97:72]) by mx.google.com with ESMTPS id vy7si29117122pbc.187.2014.12.23.04.52.27 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Tue, 23 Dec 2014 04:52:28 -0800 (PST) Subject: Re: [RFC PATCH] oom: Don't count on mm-less current process. From: Tetsuo Handa References: <201412202042.ECJ64551.FHOOJOQLFFtVMS@I-love.SAKURA.ne.jp> <20141222202511.GA9485@dhcp22.suse.cz> <201412231000.AFG78139.SJMtOOLFVFFQOH@I-love.SAKURA.ne.jp> <20141223095159.GA28549@dhcp22.suse.cz> <201412232046.FHB81206.OVMOOSJHQFFFLt@I-love.SAKURA.ne.jp> In-Reply-To: <201412232046.FHB81206.OVMOOSJHQFFFLt@I-love.SAKURA.ne.jp> Message-Id: <201412232057.CID73463.FJFOtFLSOOVHQM@I-love.SAKURA.ne.jp> Date: Tue, 23 Dec 2014 20:57:23 +0900 Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-linux-mm@kvack.org List-ID: To: mhocko@suse.cz Cc: akpm@linux-foundation.org, linux-mm@kvack.org, rientjes@google.com, oleg@redhat.com Tetsuo Handa wrote: > If such a delay is theoretically impossible, I'm OK with your patch. > Oops, I forgot to mention that task_unlock(p) should be called before put_task_struct(p), in case p->usage == 1 at put_task_struct(p). * If the task is already exiting, don't alarm the sysadmin or kill * its children or threads, just set TIF_MEMDIE so it can die quickly */ - if (task_will_free_mem(p)) { + task_lock(p); + if (p->mm && task_will_free_mem(p)) { set_tsk_thread_flag(p, TIF_MEMDIE); put_task_struct(p); + task_unlock(p); return; } + task_unlock(p); if (__ratelimit(&oom_rs)) dump_header(p, gfp_mask, order, memcg, nodemask); -- 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