From: Li Zefan Subject: [PATCH 3/4] cgroup: remove bogus comments Date: Wed, 17 Sep 2014 18:19:24 +0800 Message-ID: <5419602C.4080303@huawei.com> References: <54195FE1.9030607@huawei.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <54195FE1.9030607-hv44wF8Li93QT0dZR+AlfA@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Tejun Heo Cc: cgroups , LKML We never grab cgroup mutex in fork and exit paths no matter whether notify_on_release is set or not. Signed-off-by: Zefan Li --- kernel/cgroup.c | 8 -------- 1 file changed, 8 deletions(-) diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 26b8cb9..1abb554 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -967,14 +967,6 @@ static struct cgroup *task_cgroup_from_root(struct task_struct *task, * knows that the cgroup won't be removed, as cgroup_rmdir() * needs that mutex. * - * The fork and exit callbacks cgroup_fork() and cgroup_exit(), don't - * (usually) take cgroup_mutex. These are the two most performance - * critical pieces of code here. The exception occurs on cgroup_exit(), - * when a task in a notify_on_release cgroup exits. Then cgroup_mutex - * is taken, and if the cgroup count is zero, a usermode call made - * to the release agent with the name of the cgroup (path relative to - * the root of cgroup file system) as the argument. - * * A cgroup can only be deleted if both its 'count' of using tasks * is zero, and its list of 'children' cgroups is empty. Since all * tasks in the system use _some_ cgroup, and since there is always at -- 1.8.0.2