From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758713AbaELO6G (ORCPT ); Mon, 12 May 2014 10:58:06 -0400 Received: from cantor2.suse.de ([195.135.220.15]:35387 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758634AbaELO6E (ORCPT ); Mon, 12 May 2014 10:58:04 -0400 Date: Mon, 12 May 2014 16:58:03 +0200 From: Michal Hocko To: Tejun Heo Cc: lizefan@huawei.com, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, hannes@cmpxchg.org Subject: [PATCH] memcg: deprecate memory.force_empty knob Message-ID: <20140512145803.GF9564@dhcp22.suse.cz> References: <1399671091-23867-1-git-send-email-tj@kernel.org> <1399671091-23867-3-git-send-email-tj@kernel.org> <20140512145324.GE9564@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140512145324.GE9564@dhcp22.suse.cz> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org And this one for deprecating force_empty. --- >>From 9bb3119900baa07b92fac932991cf94dd930f907 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Mon, 12 May 2014 16:20:46 +0200 Subject: [PATCH] memcg: deprecate memory.force_empty knob force_empty has been introduced primarily to drop memory before it gets reparented on the group removal. This alone doesn't sound fully justified because reparented pages which are not in use can reclaimed also later when there is a memory pressure on the parent level. Signed-off-by: Michal Hocko --- Documentation/cgroups/memory.txt | 3 +++ mm/memcontrol.c | 4 ++++ 2 files changed, 7 insertions(+) diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt index f0f67b44ea07..fc9fad984bfb 100644 --- a/Documentation/cgroups/memory.txt +++ b/Documentation/cgroups/memory.txt @@ -477,6 +477,9 @@ About use_hierarchy, see Section 6. write will still return success. In this case, it is expected that memory.kmem.usage_in_bytes == memory.usage_in_bytes. + Please note that this knob is considered deprecated and will be removed + in future. + About use_hierarchy, see Section 6. 5.2 stat file diff --git a/mm/memcontrol.c b/mm/memcontrol.c index b030b15b626a..912104d6d2a9 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4793,6 +4793,10 @@ static int mem_cgroup_force_empty_write(struct cgroup_subsys_state *css, if (mem_cgroup_is_root(memcg)) return -EINVAL; + pr_info("%s (%d): memory.force_empty is deprecated and will be removed.", + current->comm, task_pid_nr(current)); + pr_cont(" Let us know if you know if it needed in your usecase at"); + pr_cont(" linux-mm@kvack.org\n"); return mem_cgroup_force_empty(memcg); } -- 2.0.0.rc0 -- Michal Hocko SUSE Labs