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 1D5926B0038 for ; Tue, 28 Nov 2017 08:00:21 -0500 (EST) Received: by mail-wr0-f198.google.com with SMTP id d14so148095wrg.15 for ; Tue, 28 Nov 2017 05:00:21 -0800 (PST) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id 10si1885647edw.228.2017.11.28.05.00.19 for (version=TLS1 cipher=AES128-SHA bits=128/128); Tue, 28 Nov 2017 05:00:19 -0800 (PST) Date: Tue, 28 Nov 2017 14:00:17 +0100 From: Michal Hocko Subject: Re: [PATCH] mm,oom: Set ->signal->oom_mm to all thread groups sharing the victim's mm. Message-ID: <20171128130017.ma4qzyjay7p2zsbg@dhcp22.suse.cz> References: <1511872888-4579-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1511872888-4579-1-git-send-email-penguin-kernel@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 On Tue 28-11-17 21:41:28, Tetsuo Handa wrote: > Due to commit 696453e66630ad45 ("mm, oom: task_will_free_mem should skip > oom_reaped tasks") and patch "mm,oom: Use ALLOC_OOM for OOM victim's last > second allocation.", thread groups sharing the OOM victim's mm without > setting ->signal->oom_mm before task_will_free_mem(current) is called > might fail to try ALLOC_OOM allocation attempt. Look, this is getting insane. The code complexity grows without any real users asking for this. While this might look like an interesting excercise to you I really hate the direction you are heading. This code will always be just a heuristic and the more complicated it will be the bigger chances of other side effects there will be as well. So NACK to this unless I you can show a _real_ usecase that would _suffer_ by this corner case. -- 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