From: Nikunj A. Dadhania <nikunj@linux.vnet.ibm.com>
Date: Fri, 17 Feb 2012 03:04:30 +0000 (+0530)
Subject: sched: Remove rcu_read_lock/unlock() from select_idle_sibling()
X-Git-Tag: firefly_0821_release~3680^2~3164^2~32
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=62f6536a630affe3176deb48554d27ee58b65077;p=firefly-linux-kernel-4.4.55.git

sched: Remove rcu_read_lock/unlock() from select_idle_sibling()

select_idle_sibling() is called from select_task_rq_fair(), which
already has the RCU read lock held.

Signed-off-by: Nikunj A. Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120217030409.11748.12491.stgit@abhimanyu
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 4ab60a24ea49..6ce9992926d0 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2670,8 +2670,6 @@ static int select_idle_sibling(struct task_struct *p, int target)
 	/*
 	 * Otherwise, iterate the domains and find an elegible idle cpu.
 	 */
-	rcu_read_lock();
-
 	sd = rcu_dereference(per_cpu(sd_llc, target));
 	for_each_lower_domain(sd) {
 		sg = sd->groups;
@@ -2693,8 +2691,6 @@ next:
 		} while (sg != sd->groups);
 	}
 done:
-	rcu_read_unlock();
-
 	return target;
 }