From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f72.google.com (mail-wm0-f72.google.com [74.125.82.72]) by kanga.kvack.org (Postfix) with ESMTP id DCA216B027A for ; Thu, 19 Jan 2017 03:57:10 -0500 (EST) Received: by mail-wm0-f72.google.com with SMTP id v77so7933736wmv.5 for ; Thu, 19 Jan 2017 00:57:10 -0800 (PST) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id y62si3649963wrc.154.2017.01.19.00.57.09 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 19 Jan 2017 00:57:09 -0800 (PST) Date: Thu, 19 Jan 2017 09:57:07 +0100 From: Michal Hocko Subject: Re: [patch -mm] mm, page_alloc: warn_alloc nodemask is NULL when cpusets are disabled Message-ID: <20170119085706.GH30786@dhcp22.suse.cz> References: <279f10c2-3eaa-c641-094f-3070db67d84f@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <279f10c2-3eaa-c641-094f-3070db67d84f@suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Vlastimil Babka Cc: David Rientjes , Andrew Morton , Johannes Weiner , Mel Gorman , linux-mm@kvack.org, LKML On Thu 19-01-17 08:29:45, Vlastimil Babka wrote: > On 01/18/2017 10:51 PM, David Rientjes wrote: > > The patch "mm, page_alloc: warn_alloc print nodemask" implicitly sets the > > allocation nodemask to cpuset_current_mems_allowed when there is no > > effective mempolicy. cpuset_current_mems_allowed is only effective when > > cpusets are enabled, which is also printed by warn_alloc(), so setting > > the nodemask to cpuset_current_mems_allowed is redundant and prevents > > debugging issues where ac->nodemask is not set properly in the page > > allocator. > > > > This provides better debugging output since > > cpuset_print_current_mems_allowed() is already provided. > > > > Signed-off-by: David Rientjes > > Yes, with my current cpuset vs mempolicy debugging experience, this is > more useful (except how both nodemask and mems_allowed can change under > us, so what we print here is not necessarily the same that what > get_page_from_freelist() has seen, but that's another thing...). > > But I would suggest you change the oom killer's dump_header() the same > way than warn_alloc(). Yes please -- 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