From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f171.google.com (mail-pd0-f171.google.com [209.85.192.171]) by kanga.kvack.org (Postfix) with ESMTP id 1B08C6B0078 for ; Mon, 3 Nov 2014 19:39:04 -0500 (EST) Received: by mail-pd0-f171.google.com with SMTP id r10so12544345pdi.30 for ; Mon, 03 Nov 2014 16:39:03 -0800 (PST) Received: from lgeamrelo02.lge.com (lgeamrelo02.lge.com. [156.147.1.126]) by mx.google.com with ESMTP id oy2si16521521pdb.191.2014.11.03.16.39.01 for ; Mon, 03 Nov 2014 16:39:02 -0800 (PST) Date: Tue, 4 Nov 2014 09:40:45 +0900 From: Joonsoo Kim Subject: Re: [patch 1/3] mm: embed the memcg pointer directly into struct page Message-ID: <20141104004045.GC8412@js1304-P5Q-DELUXE> References: <1414898156-4741-1-git-send-email-hannes@cmpxchg.org> <20141103080208.GA7052@js1304-P5Q-DELUXE> <20141103150942.GA32052@phnom.home.cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20141103150942.GA32052@phnom.home.cmpxchg.org> Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: Andrew Morton , Michal Hocko , Vladimir Davydov , Tejun Heo , David Miller , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org On Mon, Nov 03, 2014 at 10:09:42AM -0500, Johannes Weiner wrote: > Hi Joonsoo, > > On Mon, Nov 03, 2014 at 05:02:08PM +0900, Joonsoo Kim wrote: > > On Sat, Nov 01, 2014 at 11:15:54PM -0400, Johannes Weiner wrote: > > > Memory cgroups used to have 5 per-page pointers. To allow users to > > > disable that amount of overhead during runtime, those pointers were > > > allocated in a separate array, with a translation layer between them > > > and struct page. > > > > Hello, Johannes. > > > > I'd like to leave this translation layer. > > Could you just disable that code with #ifdef until next user comes? > > > > In our company, we uses PAGE_OWNER on mm tree which is the feature > > saying who allocates the page. To use PAGE_OWNER needs modifying > > struct page and then needs re-compile. This re-compile makes us difficult > > to use this feature. So, we decide to implement run-time configurable > > PAGE_OWNER through page_cgroup's translation layer code. Moreover, with > > this infrastructure, I plan to implement some other debugging feature. > > > > Because of my laziness, it didn't submitted to LKML. But, I will > > submit it as soon as possible. If the code is removed, I would > > copy-and-paste the code, but, it would cause lose of the history on > > that code. So if possible, I'd like to leave that code now. > > Please re-introduce this code when your new usecase is ready to be > upstreamed. There is little reason to burden an unrelated feature > with a sizable chunk of dead code for a vague future user. Okay. 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