From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f178.google.com (mail-pf0-f178.google.com [209.85.192.178]) by kanga.kvack.org (Postfix) with ESMTP id 01D256B0005 for ; Wed, 9 Mar 2016 05:08:18 -0500 (EST) Received: by mail-pf0-f178.google.com with SMTP id 129so36646588pfw.1 for ; Wed, 09 Mar 2016 02:08:17 -0800 (PST) Received: from mail-pf0-f177.google.com (mail-pf0-f177.google.com. [209.85.192.177]) by mx.google.com with ESMTPS id 77si6429724pfq.237.2016.03.09.02.08.17 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 09 Mar 2016 02:08:17 -0800 (PST) Received: by mail-pf0-f177.google.com with SMTP id u190so7289829pfb.3 for ; Wed, 09 Mar 2016 02:08:17 -0800 (PST) Date: Wed, 9 Mar 2016 11:08:14 +0100 From: Michal Hocko Subject: Re: [PATCH] mm: memcontrol: drop unnecessary task_will_free_mem() check. Message-ID: <20160309100814.GC27018@dhcp22.suse.cz> References: <1457450110-6005-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> <20160308181432.GA9091@cmpxchg.org> <201603090805.FGE48462.tFJSLMOFHVOOQF@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201603090805.FGE48462.tFJSLMOFHVOOQF@I-love.SAKURA.ne.jp> Sender: owner-linux-mm@kvack.org List-ID: To: Tetsuo Handa Cc: hannes@cmpxchg.org, vdavydov@virtuozzo.com, linux-mm@kvack.org On Wed 09-03-16 08:05:11, Tetsuo Handa wrote: [...] > Also, what is the reason we do not need below change? > I think there is a small race window because oom_killer_disabled needs to be > checked after oom_killer_disable() held oom_lock. Is it because all userspace > processes except current are frozen before oom_killer_disable() is called and > not-yet frozen threads (i.e. kernel threads) never call mem_cgroup_out_of_memory() ? Please refer to c32b3cbe0d06 ("oom, PM: make OOM detection in the freezer path raceless"). It should explain this. -- Michal Hocko SUSE Labs -- 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