From b1a92da263930688ebd5d18e3f4c354e366cd469 Mon Sep 17 00:00:00 2001
From: Julia Cartwright <julia@ni.com>
Date: Wed, 12 Oct 2016 11:21:14 -0500
Subject: [PATCH 369/518] rcu: enable rcu_normal_after_boot by default for RT

The forcing of an expedited grace period is an expensive and very
RT-application unfriendly operation, as it forcibly preempts all running
tasks on CPUs which are preventing the gp from expiring.

By default, as a policy decision, disable the expediting of grace
periods (after boot) on configurations which enable PREEMPT_RT_FULL.

Suggested-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Julia Cartwright <julia@ni.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 kernel/rcu/update.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index c63c88a0de7e5..2006a09680aaa 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -66,7 +66,7 @@ extern int rcu_expedited; /* from sysctl */
 module_param(rcu_expedited, int, 0);
 extern int rcu_normal; /* from sysctl */
 module_param(rcu_normal, int, 0);
-static int rcu_normal_after_boot;
+static int rcu_normal_after_boot = IS_ENABLED(CONFIG_PREEMPT_RT_FULL);
 module_param(rcu_normal_after_boot, int, 0);
 #endif /* #ifndef CONFIG_TINY_RCU */
 
-- 
2.41.0

