From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758188AbaDVVgi (ORCPT ); Tue, 22 Apr 2014 17:36:38 -0400 Received: from mail-pa0-f48.google.com ([209.85.220.48]:51091 "EHLO mail-pa0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756874AbaDVVg3 (ORCPT ); Tue, 22 Apr 2014 17:36:29 -0400 Date: Tue, 22 Apr 2014 14:35:14 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@eggly.anvils To: Michal Hocko cc: Oleg Nesterov , Andrew Morton , Peter Chiang , KAMEZAWA Hiroyuki , Balbir Singh , Johannes Weiner , "ccross@android.com" , "lizefan@huawei.com" , "tj@kernel.org" , "pavel@ucw.cz" , "ebiederm@xmission.com" , "guillaume@morinfr.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 0/2] memcg: mm_update_next_owner() should skip kthreads In-Reply-To: <20140422132102.GN29311@dhcp22.suse.cz> Message-ID: References: <1397617379-26895-1-git-send-email-pchiang@nvidia.com> <80341664FB79C2419999599F48F738410227327881@HKMAIL01.nvidia.com> <80341664FB79C2419999599F48F738410227327888@HKMAIL01.nvidia.com> <20140416135741.GA9407@redhat.com> <80341664FB79C2419999599F48F7384102273279C3@HKMAIL01.nvidia.com> <20140418162359.GA4398@redhat.com> <20140418172631.GA13323@redhat.com> <20140418182444.GB22235@dhcp22.suse.cz> <20140418184441.GA26046@redhat.com> <20140422105228.GJ29311@dhcp22.suse.cz> <20140422132102.GN29311@dhcp22.suse.cz> User-Agent: Alpine 2.11 (LSU 23 2013-08-11) 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 Tue, 22 Apr 2014, Michal Hocko wrote: > On Tue 22-04-14 12:52:28, Michal Hocko wrote: > > On Fri 18-04-14 20:44:41, Oleg Nesterov wrote: > [...] > > > I do not even understand why do we have CONFIG_MM_OWNER, perhaps it should > > > die? > > > > I have to dig into history to check why it has been introduced in the > > first place. It might be possible it is not relevant anymore. > > There didn't seem to be any other user of CONFIG_MM_OWNER outside of > MEMCG so it seems that a separate config option seems like an overkill. > Regarding the mm->owner itself it is hard to live without it at the > moment. Most of the charging places do charge the current task_struct > but there are some that rely on mm and we would need mm->task mapping. > The last obstacle would be threads migration but that one should go away > with unified hierarchy AFAIR. Balbir had another user for mm->owner in mmotm back in 2008, his memrlimit controller; but that didn't make it through to mainline. Hugh