From d4cf05d7da773f49f3176cbbbba15a3e4b847b3b Mon Sep 17 00:00:00 2001
From: "Joel Fernandes (Google)" <joel@joelfernandes.org>
Date: Tue, 16 Jul 2019 18:12:21 -0400
Subject: [PATCH] rcu: Remove redundant debug_locks check in
 rcu_read_lock_sched_held()

commit 9147089bee3a6b504821dd8462e2be229e6dbfae upstream.

The debug_locks flag can never be true at the end of
rcu_read_lock_sched_held() because it is already checked by the earlier
call todebug_lockdep_rcu_enabled().   This commit therefore removes this
redundant check.

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index c3bf44ba42e5..bb961cd89e76 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -93,17 +93,13 @@ module_param(rcu_normal_after_boot, int, 0);
  */
 int rcu_read_lock_sched_held(void)
 {
-	int lockdep_opinion = 0;
-
 	if (!debug_lockdep_rcu_enabled())
 		return 1;
 	if (!rcu_is_watching())
 		return 0;
 	if (!rcu_lockdep_current_cpu_online())
 		return 0;
-	if (debug_locks)
-		lockdep_opinion = lock_is_held(&rcu_sched_lock_map);
-	return lockdep_opinion || !preemptible();
+	return lock_is_held(&rcu_sched_lock_map) || !preemptible();
 }
 EXPORT_SYMBOL(rcu_read_lock_sched_held);
 #endif
-- 
2.7.4