cgroup: remove synchronize_rcu() from cgroup_diput()

Free cgroup via call_rcu(). The actual work is done through
workqueue.

Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 8118a3120378..900af5964f55 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -203,6 +203,7 @@ struct cgroup {
 
         /* For RCU-protected deletion */
         struct rcu_head rcu_head;
+        struct work_struct free_work;
 
         /* List of events which userspace want to receive */
         struct list_head event_list;