From 0457ef0e6ef82a80677559773add9b11585860ec Mon Sep 17 00:00:00 2001 From: Julia Cartwright Date: Wed, 12 Oct 2016 11:21:14 -0500 Subject: [PATCH 302/352] 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 Signed-off-by: Julia Cartwright Signed-off-by: Sebastian Andrzej Siewior --- 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 949714f..ee02e1e 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -62,7 +62,7 @@ #ifndef CONFIG_TINY_RCU module_param(rcu_expedited, int, 0); 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 */ -- 2.7.4