[PATCH] NOHZ: Fix RCU handling
When a CPU is needed for RCU the tick has to continue even when it was
stopped before.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 95e41f7f..9234e44 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -191,19 +191,19 @@
next_jiffies = get_next_timer_interrupt(last_jiffies);
delta_jiffies = next_jiffies - last_jiffies;
+ if (rcu_needs_cpu(cpu))
+ delta_jiffies = 1;
/*
* Do not stop the tick, if we are only one off
* or if the cpu is required for rcu
*/
- if (!ts->tick_stopped && (delta_jiffies == 1 || rcu_needs_cpu(cpu)))
+ if (!ts->tick_stopped && delta_jiffies == 1)
goto out;
/* Schedule the tick, if we are at least one jiffie off */
if ((long)delta_jiffies >= 1) {
- if (rcu_needs_cpu(cpu))
- delta_jiffies = 1;
- else
+ if (delta_jiffies > 1)
cpu_set(cpu, nohz_cpu_mask);
/*
* nohz_stop_sched_tick can be called several times before