From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: [PATCH 09/17] cgroup: lock cgroup_mutex in cgroup_init_subsys() Date: Mon, 12 Nov 2012 19:01:36 -0800 Message-ID: <1352775704-9023-10-git-send-email-tj@kernel.org> References: <1352775704-9023-1-git-send-email-tj@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1352775704-9023-1-git-send-email-tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: mhocko-AlSwsSmVLrQ@public.gmane.org, Tejun Heo List-Id: containers.vger.kernel.org Make cgroup_init_subsys() grab cgroup_mutex while initializing a subsystem so that all helpers and callbacks are called under the context they expect. This isn't strictly necessary as cgroup_init_subsys() doesn't race with anybody but will allow adding lockdep assertions. Signed-off-by: Tejun Heo --- kernel/cgroup.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 6df17cb..76f1a01 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -4317,6 +4317,8 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss) printk(KERN_INFO "Initializing cgroup subsys %s\n", ss->name); + mutex_lock(&cgroup_mutex); + /* init base cftset */ cgroup_init_cftsets(ss); @@ -4346,6 +4348,8 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss) if (ss->post_create) ss->post_create(dummytop); + mutex_unlock(&cgroup_mutex); + /* this function shouldn't be used with modular subsystems, since they * need to register a subsys_id, among other things */ BUG_ON(ss->module); -- 1.7.11.7