From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757907Ab3K0VjH (ORCPT ); Wed, 27 Nov 2013 16:39:07 -0500 Received: from mail-yh0-f49.google.com ([209.85.213.49]:62052 "EHLO mail-yh0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754622Ab3K0VjD (ORCPT ); Wed, 27 Nov 2013 16:39:03 -0500 Date: Wed, 27 Nov 2013 13:38:59 -0800 (PST) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Johannes Weiner cc: Andrew Morton , Michal Hocko , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [patch] mm: memcg: do not declare OOM from __GFP_NOFAIL allocations In-Reply-To: <20131127163916.GB3556@cmpxchg.org> Message-ID: References: <1385140676-5677-1-git-send-email-hannes@cmpxchg.org> <20131127163916.GB3556@cmpxchg.org> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 27 Nov 2013, Johannes Weiner wrote: > > Ah, this is because of 3168ecbe1c04 ("mm: memcg: use proper memcg in limit > > bypass") which just bypasses all of these allocations and charges the root > > memcg. So if allocations want to bypass memcg isolation they just have to > > be __GFP_NOFAIL? > > I don't think we have another option. > We don't give __GFP_NOFAIL allocations access to memory reserves in the page allocator and we do call the oom killer for them so that a process is killed so that memory is freed. Why do we have a different policy for memcg?