From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756411AbcE0RZL (ORCPT ); Fri, 27 May 2016 13:25:11 -0400 Received: from gum.cmpxchg.org ([85.214.110.215]:56706 "EHLO gum.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755559AbcE0RZK (ORCPT ); Fri, 27 May 2016 13:25:10 -0400 Date: Fri, 27 May 2016 13:23:04 -0400 From: Johannes Weiner To: Vladimir Davydov Cc: Andrew Morton , Michal Hocko , Tetsuo Handa , David Rientjes , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] mm: oom: deduplicate victim selection code for memcg and global oom Message-ID: <20160527172304.GD2531@cmpxchg.org> References: <40e03fd7aaf1f55c75d787128d6d17c5a71226c2.1464358556.git.vdavydov@virtuozzo.com> <3bbc7b70dae6ace0b8751e0140e878acfdfffd74.1464358556.git.vdavydov@virtuozzo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3bbc7b70dae6ace0b8751e0140e878acfdfffd74.1464358556.git.vdavydov@virtuozzo.com> User-Agent: Mutt/1.6.1 (2016-04-27) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 27, 2016 at 05:17:42PM +0300, Vladimir Davydov wrote: > When selecting an oom victim, we use the same heuristic for both memory > cgroup and global oom. The only difference is the scope of tasks to > select the victim from. So we could just export an iterator over all > memcg tasks and keep all oom related logic in oom_kill.c, but instead we > duplicate pieces of it in memcontrol.c reusing some initially private > functions of oom_kill.c in order to not duplicate all of it. That looks > ugly and error prone, because any modification of select_bad_process > should also be propagated to mem_cgroup_out_of_memory. > > Let's rework this as follows: keep all oom heuristic related code > private to oom_kill.c and make oom_kill.c use exported memcg functions > when it's really necessary (like in case of iterating over memcg tasks). > > Signed-off-by: Vladimir Davydov Cool work! I'll do a full review after the rebase on top of Michal's stuff.