[patch 48/48] sched: Default enable HRTICK when deferred rearming is enabled

[Thomas Gleixner]

From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>

The deferred rearm of the clock event device after an interrupt and and
other hrtimer optimizations allow now to enable HRTICK for generic entry
architectures.

This decouples preemption from CONFIG_HZ, leaving only the periodic
load-balancer and various accounting things relying on the tick.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxx>
---
 kernel/sched/features.h |    5 +++++
 1 file changed, 5 insertions(+)
--- a/kernel/sched/features.h
+++ b/kernel/sched/features.h
@@ -63,8 +63,13 @@ SCHED_FEAT(DELAY_ZERO, true)
  */
 SCHED_FEAT(WAKEUP_PREEMPTION, true)
 
+#ifdef CONFIG_HRTIMER_REARM_DEFERRED
+SCHED_FEAT(HRTICK, true)
+SCHED_FEAT(HRTICK_DL, true)
+#else
 SCHED_FEAT(HRTICK, false)
 SCHED_FEAT(HRTICK_DL, false)
+#endif
 
 /*
  * Decrement CPU capacity based on time not spent running tasks