From: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> v4.14.137-rt65-rc1 stable review patch. If anyone has any objections, please let me know. ----------- [ Upstream commit c6c058c10577815a2491ce661876cff00a4c3b15 ] On RT rcu_normal_after_boot is enabled by default. Don't allow to disable it on RT because the "expedited rcu" would introduce latency spikes. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Signed-off-by: Tom Zanussi <zanussi@xxxxxxxxxx> --- kernel/rcu/update.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index 2006a09680aa..307592810f6b 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -67,7 +67,9 @@ module_param(rcu_expedited, int, 0); extern int rcu_normal; /* from sysctl */ module_param(rcu_normal, int, 0); static int rcu_normal_after_boot = IS_ENABLED(CONFIG_PREEMPT_RT_FULL); +#ifndef CONFIG_PREEMPT_RT_FULL module_param(rcu_normal_after_boot, int, 0); +#endif #endif /* #ifndef CONFIG_TINY_RCU */ #ifdef CONFIG_DEBUG_LOCK_ALLOC -- 2.14.1
