Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753739AbbBZRev (ORCPT ); Thu, 26 Feb 2015 12:34:51 -0500 Received: from cantor2.suse.de ([195.135.220.15]:36487 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751570AbbBZRet (ORCPT ); Thu, 26 Feb 2015 12:34:49 -0500 Date: Thu, 26 Feb 2015 18:34:45 +0100 From: Michal Hocko To: David Rientjes , Andrew Morton Cc: Johannes Weiner , "\\\"Rafael J. Wysocki\\\"" , Tetsuo Handa , linux-mm@kvack.org, LKML Subject: Re: [PATCH -v2] mm, oom: do not fail __GFP_NOFAIL allocation if oom killer is disbaled Message-ID: <20150226173445.GG14878@dhcp22.suse.cz> References: <1424801964-1602-1-git-send-email-mhocko@suse.cz> <20150224191127.GA14718@phnom.home.cmpxchg.org> <20150225140826.GD26680@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1941 Lines: 56 On Wed 25-02-15 12:41:07, David Rientjes wrote: > On Wed, 25 Feb 2015, Michal Hocko wrote: > > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > > index 2d224bbdf8e8..c2ff40a30003 100644 > > --- a/mm/page_alloc.c > > +++ b/mm/page_alloc.c > > @@ -2363,7 +2363,8 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, > > goto out; > > } > > /* Exhausted what can be done so it's blamo time */ > > - if (out_of_memory(ac->zonelist, gfp_mask, order, ac->nodemask, false)) > > + if (out_of_memory(ac->zonelist, gfp_mask, order, ac->nodemask, false) > > + || WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL)) > > *did_some_progress = 1; > > out: > > oom_zonelist_unlock(ac->zonelist, gfp_mask); > > Eek, not sure we actually need to play any games with did_some_progress, > it might be clearer just to do this We would loose the warning which _might_ be helpful and I also find this place better because it is close to the out_of_memory and this one has only one failure mode. So I would prefer to stick with this unless there are big objections. > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -2760,7 +2760,7 @@ retry: > &did_some_progress); > if (page) > goto got_pg; > - if (!did_some_progress) > + if (!did_some_progress && !(gfp_mask & __GFP_NOFAIL)) > goto nopage; > } > /* Wait for some write requests to complete then retry */ > > Either way you decide, feel free to add my > > Acked-by: David Rientjes Thanks! Andrew, should I repost or you can pick it up from this thread? Assuming you and others do not have objections of course. -- Michal Hocko SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/