sched: rt throttling vs no_hz

We need to teach no_hz about the rt throttling because its tick driven.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 5 insertions, 0 deletions

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index cb89fa8db110..5f9fb645b725 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -153,6 +153,7 @@ void tick_nohz_update_jiffies(void)
 void tick_nohz_stop_sched_tick(void)
 {
         unsigned long seq, last_jiffies, next_jiffies, delta_jiffies, flags;
+        unsigned long rt_jiffies;
         struct tick_sched *ts;
         ktime_t last_update, expires, now, delta;
         struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev;
@@ -216,6 +217,10 @@ void tick_nohz_stop_sched_tick(void)
         next_jiffies = get_next_timer_interrupt(last_jiffies);
         delta_jiffies = next_jiffies - last_jiffies;
 
+        rt_jiffies = rt_needs_cpu(cpu);
+        if (rt_jiffies && rt_jiffies < delta_jiffies)
+                delta_jiffies = rt_jiffies;
+
         if (rcu_needs_cpu(cpu))
                 delta_jiffies = 1;
         /*