[tip: core/rcu] rcu: Priority-boost-related sleeps to idle priority

[tip-bot2 for Paul E. McKenney]

The following commit has been merged into the core/rcu branch of tip:

Commit-ID:     a9352f72d6a9e8fe4840b9f0d97af8f5a6c52c79
Gitweb:        https://git.kernel.org/tip/a9352f72d6a9e8fe4840b9f0d97af8f5a6c52c79
Author:        Paul E. McKenney <paulmck@xxxxxxxxxx>
AuthorDate:    Thu, 07 May 2020 16:34:38 -07:00
Committer:     Paul E. McKenney <paulmck@xxxxxxxxxx>
CommitterDate: Mon, 29 Jun 2020 11:58:50 -07:00

rcu: Priority-boost-related sleeps to idle priority

This commit converts the long-standing schedule_timeout_interruptible()
call used by RCU's priority-boosting kthreads to schedule_timeout_idle().
This conversion avoids polluting the load-average with RCU-related
sleeping.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
 kernel/rcu/tree_plugin.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 3522236..25296c1 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -1033,7 +1033,7 @@ static int rcu_boost_kthread(void *arg)
 		if (spincnt > 10) {
 			WRITE_ONCE(rnp->boost_kthread_status, RCU_KTHREAD_YIELDING);
 			trace_rcu_utilization(TPS("End boost kthread@rcu_yield"));
-			schedule_timeout_interruptible(2);
+			schedule_timeout_idle(2);
 			trace_rcu_utilization(TPS("Start boost kthread@rcu_yield"));
 			spincnt = 0;
 		}