From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-f50.google.com (mail-wg0-f50.google.com [74.125.82.50]) by kanga.kvack.org (Postfix) with ESMTP id 6EEBB6B0072 for ; Wed, 4 Mar 2015 12:41:33 -0500 (EST) Received: by wghb13 with SMTP id b13so48243743wgh.0 for ; Wed, 04 Mar 2015 09:41:32 -0800 (PST) Received: from gum.cmpxchg.org (gum.cmpxchg.org. [85.214.110.215]) by mx.google.com with ESMTPS id s5si4068457wiy.105.2015.03.04.09.41.31 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 04 Mar 2015 09:41:31 -0800 (PST) Date: Wed, 4 Mar 2015 12:40:56 -0500 From: Johannes Weiner Subject: Re: [PATCH] mm: memcontrol: Let mem_cgroup_move_account() have effect only if MMU enabled Message-ID: <20150304174056.GA20376@phnom.home.cmpxchg.org> References: <54F4E739.6040805@qq.com> <20150303134524.GE2409@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150303134524.GE2409@dhcp22.suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Chen Gang <762976180@qq.com>, cgroups@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , "linux-kernel@vger.kernel.org" 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 -- 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