From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f198.google.com (mail-wr0-f198.google.com [209.85.128.198]) by kanga.kvack.org (Postfix) with ESMTP id 3A34A6B0253 for ; Thu, 7 Dec 2017 07:22:54 -0500 (EST) Received: by mail-wr0-f198.google.com with SMTP id w95so4040570wrc.20 for ; Thu, 07 Dec 2017 04:22:54 -0800 (PST) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id n47si3897104wrn.542.2017.12.07.04.22.52 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 07 Dec 2017 04:22:52 -0800 (PST) Date: Thu, 7 Dec 2017 13:22:49 +0100 From: Michal Hocko Subject: Re: [PATCH] mm,oom: use ALLOC_OOM for OOM victim's last second allocation Message-ID: <20171207122249.GI20234@dhcp22.suse.cz> References: <1512646940-3388-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> <20171207115127.GH20234@dhcp22.suse.cz> <201712072059.HAJ04643.QSJtVMFLFOOOHF@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201712072059.HAJ04643.QSJtVMFLFOOOHF@I-love.SAKURA.ne.jp> Sender: owner-linux-mm@kvack.org List-ID: To: Tetsuo Handa Cc: akpm@linux-foundation.org, linux-mm@kvack.org, aarcange@redhat.com, rientjes@google.com, hannes@cmpxchg.org, mjaggi@caviumnetworks.com, oleg@redhat.com, vdavydov.dev@gmail.com On Thu 07-12-17 20:59:34, Tetsuo Handa wrote: > Michal Hocko wrote: > > On Thu 07-12-17 20:42:20, Tetsuo Handa wrote: > > > Manish Jaggi noticed that running LTP oom01/oom02 ltp tests with high core > > > count causes random kernel panics when an OOM victim which consumed memory > > > in a way the OOM reaper does not help was selected by the OOM killer [1]. > > > Since commit 696453e66630ad45 ("mm, oom: task_will_free_mem should skip > > > oom_reaped tasks") changed task_will_free_mem(current) in out_of_memory() > > > to return false as soon as MMF_OOM_SKIP is set, many threads sharing the > > > victim's mm were not able to try allocation from memory reserves after the > > > OOM reaper gave up reclaiming memory. > > > > > > Therefore, this patch allows OOM victims to use ALLOC_OOM watermark for > > > last second allocation attempt. > > > > > > [1] http://lkml.kernel.org/r/e6c83a26-1d59-4afd-55cf-04e58bdde188@caviumnetworks.com > > > > > > Fixes: 696453e66630ad45 ("mm, oom: task_will_free_mem should skip oom_reaped tasks") > > > Signed-off-by: Tetsuo Handa > > > Reported-by: Manish Jaggi > > > Acked-by: Michal Hocko > > > > I haven't acked _this_ patch! I will have a look but the patch is > > different enough from the original that keeping any acks or reviews is > > inappropriate. Do not do it again! > > I see. But nothing has changed except that this is called before entering > into the OOM killer. I assumed that this is a trivial change. Let the reviewers judge and have them add their acks/reviewed-bys again. -- 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