2 files changed, 10 insertions, 1 deletions

diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 88e863460726..3ac78a2f4b5a 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -260,6 +260,9 @@ struct css_set {
          * during subsystem registration (at boot time).
          */
         struct cgroup_subsys_state *subsys[CGROUP_SUBSYS_COUNT];
+
+        /* For RCU-protected deletion */
+        struct rcu_head rcu_head;
 };
 
 /*
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 3e356b05b2d5..bf8dd1a9f2d1 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -267,6 +267,12 @@ static struct hlist_head *css_set_hash(struct cgroup_subsys_state *css[])
         return &css_set_table[index];
 }
 
+static void free_css_set_rcu(struct rcu_head *obj)
+{
+        struct css_set *cg = container_of(obj, struct css_set, rcu_head);
+        kfree(cg);
+}
+
 /* We don't maintain the lists running through each css_set to its
  * task until after the first call to cgroup_iter_start(). This
  * reduces the fork()/exit() overhead for people who have cgroups
@@ -310,7 +316,7 @@ static void __put_css_set(struct css_set *cg, int taskexit)
         }
 
         write_unlock(&css_set_lock);
-        kfree(cg);
+        call_rcu(&cg->rcu_head, free_css_set_rcu);
 }
 
 /*