From fc390cde362309f6892bb719194f242c466a978b Mon Sep 17 00:00:00 2001
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Date: Thu, 6 May 2010 11:42:52 -0700
Subject: [PATCH] rcu: need barrier() in UP synchronize_sched_expedited()

If synchronize_sched_expedited() is ever to be called from within
kernel/sched.c in a !SMP PREEMPT kernel, the !SMP implementation needs
a barrier().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
---
 kernel/sched.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/sched.c b/kernel/sched.c
index 155a16d52146..fbaf3128d010 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -8932,6 +8932,7 @@ struct cgroup_subsys cpuacct_subsys = {
 
 void synchronize_sched_expedited(void)
 {
+	barrier();
 }
 EXPORT_SYMBOL_GPL(synchronize_sched_expedited);
 
-- 
2.39.5