From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf0-f69.google.com (mail-lf0-f69.google.com [209.85.215.69]) by kanga.kvack.org (Postfix) with ESMTP id 743806B0263 for ; Thu, 12 May 2016 12:38:28 -0400 (EDT) Received: by mail-lf0-f69.google.com with SMTP id j8so56003785lfd.0 for ; Thu, 12 May 2016 09:38:28 -0700 (PDT) Received: from mail-wm0-f67.google.com (mail-wm0-f67.google.com. [74.125.82.67]) by mx.google.com with ESMTPS id j80si46548061wmj.57.2016.05.12.09.38.27 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 12 May 2016 09:38:27 -0700 (PDT) Received: by mail-wm0-f67.google.com with SMTP id n129so16895542wmn.1 for ; Thu, 12 May 2016 09:38:27 -0700 (PDT) Date: Thu, 12 May 2016 18:38:25 +0200 From: Michal Hocko Subject: Re: [PATCH v5] mm: Add memory allocation watchdog kernel thread. Message-ID: <20160512163824.GA4940@dhcp22.suse.cz> References: <004b01d1a9d1$3817fc10$a847f430$@alibaba-inc.com> <006e01d1a9d8$5c7a15f0$156e41d0$@alibaba-inc.com> <201605130009.EAJ35441.JLtFVOHFOSOMQF@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201605130009.EAJ35441.JLtFVOHFOSOMQF@I-love.SAKURA.ne.jp> Sender: owner-linux-mm@kvack.org List-ID: To: Tetsuo Handa Cc: hillf.zj@alibaba-inc.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org On Fri 13-05-16 00:09:07, Tetsuo Handa wrote: [...] > Michal, this version eliminated overhead of walking the process list > when nothing is wrong. You are aware of the possibility of > debug_show_all_locks() failing to report the culprit, aren't you? > So, what are unacceptable major problems for you? I do not remember complaining about anything unacceptable for this patch. I just thought it was way too large the last time I have looked at it. Johannes was suggesting to simply extend warn_alloc_failed to also report too many retries with some extended information as a more lightweight approach. It wouldn't give as much information as your watchdog but maybe it would be sufficient to figure out that something really bad is going on. Dunno but I would rather see a more lightweight debugging aid than a lot of code which sit basically unused most of the time. That being said I cannot comment on this particular version as I haven't checked it properly yet. -- 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