From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f177.google.com (mail-wi0-f177.google.com [209.85.212.177]) by kanga.kvack.org (Postfix) with ESMTP id B1F896B006E for ; Wed, 4 Mar 2015 14:06:42 -0500 (EST) Received: by wibhm9 with SMTP id hm9so9888831wib.2 for ; Wed, 04 Mar 2015 11:06:42 -0800 (PST) Received: from gum.cmpxchg.org (gum.cmpxchg.org. [85.214.110.215]) by mx.google.com with ESMTPS id jd11si31187804wic.14.2015.03.04.11.06.40 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 04 Mar 2015 11:06:41 -0800 (PST) Date: Wed, 4 Mar 2015 14:06:35 -0500 From: Johannes Weiner Subject: Re: [PATCH] memcg: make CONFIG_MEMCG depend on CONFIG_MMU Message-ID: <20150304190635.GC21350@phnom.home.cmpxchg.org> References: <1425492428-27562-1-git-send-email-mhocko@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1425492428-27562-1-git-send-email-mhocko@suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Andrew Morton , Chen Gang <762976180@qq.com>, linux-mm@kvack.org, LKML On Wed, Mar 04, 2015 at 07:07:08PM +0100, Michal Hocko wrote: > CONFIG_MEMCG might be currently enabled also for !MMU architectures > which was probably an omission because Balbir had this on the TODO > list section (https://lkml.org/lkml/2008/3/16/59) > " > Only when CONFIG_MMU is enabled, is the virtual address space control > enabled. Should we do this for nommu cases as well? My suspicion is > that we don't have to. > " > I do not see any traces for !MMU requests after then. The code compiles > with !MMU but I haven't heard about anybody using it in the real life > so it is not clear to me whether it works and it is usable at all > considering how !MMU configuration is restricted. > > Let's make CONFIG_MEMCG depend on CONFIG_MMU to make our support > explicit and also to get rid of few ifdefs in the code base. > > Acked-by: Johannes Weiner > Signed-off-by: Michal Hocko Sorry about the misunderstanding, I actually acked Chen's patch. As I said, there is nothing inherent in memcg that would prevent using it on NOMMU systems except for this charges-follow-tasks feature, so I'd rather fix the compiler warning than adding this dependency. Thanks -- 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