Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754363Ab3DOBG5 (ORCPT ); Sun, 14 Apr 2013 21:06:57 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:39642 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753491Ab3DOBG4 (ORCPT ); Sun, 14 Apr 2013 21:06:56 -0400 Date: Sun, 14 Apr 2013 20:06:47 -0500 From: Serge Hallyn To: Tejun Heo Cc: lizefan@huawei.com, containers@lists.linux-foundation.org, linux-kernel@vger.kernel.org, mhocko@suse.cz, vgoyal@redhat.com, cgroups@vger.kernel.org Subject: Re: [PATCH 4/4] memcg: force use_hierarchy if sane_behavior Message-ID: <20130415010647.GE8408@sergelap> References: <1365808259-31073-1-git-send-email-tj@kernel.org> <1365808259-31073-5-git-send-email-tj@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1365808259-31073-5-git-send-email-tj@kernel.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3011 Lines: 86 Quoting Tejun Heo (tj@kernel.org): > Turn on use_hierarchy by default if sane_behavior is specified and > don't create .use_hierarchy file. > > It is debatable whether to remove .use_hierarchy file or make it ro as > the former could make transition easier in certain cases; however, the > behavior changes which will be gated by sane_behavior are intensive > including changing basic meaning of certain control knobs in a few > controllers and I don't really think keeping this piece would make > things easier in any noticeable way, so let's remove it. > > Signed-off-by: Tejun Heo Acked-by: Serge E. Hallyn > Cc: Michal Hocko > Cc: KAMEZAWA Hiroyuki > --- > include/linux/cgroup.h | 3 +++ > mm/memcontrol.c | 13 +++++++++++++ > 2 files changed, 16 insertions(+) > > diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h > index 9c300ad..c562e33 100644 > --- a/include/linux/cgroup.h > +++ b/include/linux/cgroup.h > @@ -269,6 +269,9 @@ enum { > * > * - Remount is disallowed. > * > + * - memcg: use_hierarchy is on by default and the cgroup file for > + * the flag is not created. > + * > * The followings are planned changes. > * > * - release_agent will be disallowed once replacement notification > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 9715c0c..a651131 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -5814,6 +5814,7 @@ static struct cftype mem_cgroup_files[] = { > }, > { > .name = "use_hierarchy", > + .flags = CFTYPE_INSANE, > .write_u64 = mem_cgroup_hierarchy_write, > .read_u64 = mem_cgroup_hierarchy_read, > }, > @@ -6784,6 +6785,17 @@ static void mem_cgroup_move_task(struct cgroup *cont, > } > #endif > > +/* > + * Cgroup retains root cgroups across [un]mount cycles making it necessary > + * to verify sane_behavior flag on each mount attempt. > + */ > +static void mem_cgroup_bind(struct cgroup *root) > +{ > + /* use_hierarchy is forced with sane_behavior */ > + if (cgroup_sane_behavior(root)) > + mem_cgroup_from_cont(root)->use_hierarchy = true; > +} > + > struct cgroup_subsys mem_cgroup_subsys = { > .name = "memory", > .subsys_id = mem_cgroup_subsys_id, > @@ -6794,6 +6806,7 @@ struct cgroup_subsys mem_cgroup_subsys = { > .can_attach = mem_cgroup_can_attach, > .cancel_attach = mem_cgroup_cancel_attach, > .attach = mem_cgroup_move_task, > + .bind = mem_cgroup_bind, > .base_cftypes = mem_cgroup_files, > .early_init = 0, > .use_id = 1, > -- > 1.8.1.4 > > _______________________________________________ > Containers mailing list > Containers@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/containers -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/