From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f180.google.com (mail-wi0-f180.google.com [209.85.212.180]) by kanga.kvack.org (Postfix) with ESMTP id 809C76B0072 for ; Wed, 4 Mar 2015 13:00:34 -0500 (EST) Received: by widem10 with SMTP id em10so30715528wid.0 for ; Wed, 04 Mar 2015 10:00:33 -0800 (PST) Received: from mail-wi0-x236.google.com (mail-wi0-x236.google.com. [2a00:1450:400c:c05::236]) by mx.google.com with ESMTPS id ch4si1987522wib.24.2015.03.04.10.00.28 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 04 Mar 2015 10:00:32 -0800 (PST) Received: by wibhm9 with SMTP id hm9so9568057wib.2 for ; Wed, 04 Mar 2015 10:00:28 -0800 (PST) Date: Wed, 4 Mar 2015 19:00:24 +0100 From: Michal Hocko Subject: Re: [PATCH] mm: memcontrol: Let mem_cgroup_move_account() have effect only if MMU enabled Message-ID: <20150304180024.GA26741@dhcp22.suse.cz> References: <54F4E739.6040805@qq.com> <20150303134524.GE2409@dhcp22.suse.cz> <20150304174056.GA20376@phnom.home.cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150304174056.GA20376@phnom.home.cmpxchg.org> Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: Chen Gang <762976180@qq.com>, cgroups@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , "linux-kernel@vger.kernel.org" On Wed 04-03-15 12:40:56, Johannes Weiner wrote: > On Tue, Mar 03, 2015 at 02:45:24PM +0100, Michal Hocko wrote: > > On Tue 03-03-15 06:42:01, Chen Gang wrote: > > > When !MMU, it will report warning. The related warning with allmodconfig > > > under c6x: > > > > Does it even make any sense to enable CONFIG_MEMCG when !CONFIG_MMU? > > Is anybody using this configuration and is it actually usable? My > > knowledge about CONFIG_MMU is close to zero so I might be missing > > something but I do not see a point into fixing compile warnings when > > the whole subsystem is not usable in the first place. > > It's very limited, and anonymous memory is not even charged right now, > even though it could be -- see nommu.c::do_mmap_private(). But there > is nothing inherent in the memcg functionality that would require an > MMU I guess, except for these ridiculous charge moving pte walkers. > > > > Signed-off-by: Chen Gang > > Acked-by: Johannes Weiner Thanks, I will post the patch to Andrew. -- 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