[PATCH -next] cgroup: Remove out-of-date comment in cgroup_migrate()

[Xiu Jianfeng]

From: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx>

Commit 674b745e22b3 ("cgroup: remove rcu_read_lock()/rcu_read_unlock()
in critical section of spin_lock_irq()") has removed the rcu_read_lock,
which makes the comment out-of-date, so remove it.

Signed-off-by: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx>
---
 kernel/cgroup/cgroup.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index d8ba2c67910d..415d51c713ad 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -2871,11 +2871,6 @@ int cgroup_migrate(struct task_struct *leader, bool threadgroup,
 {
 	struct task_struct *task;
 
-	/*
-	 * Prevent freeing of tasks while we take a snapshot. Tasks that are
-	 * already PF_EXITING could be freed from underneath us unless we
-	 * take an rcu_read_lock.
-	 */
 	spin_lock_irq(&css_set_lock);
 	task = leader;
 	do {
-- 
2.17.1