sched: Mark hrtimers to expire in hard interrupt context

The scheduler related hrtimers need to expire in hard interrupt context
even on PREEMPT_RT enabled kernels. Mark then as such.

No functional change.

[ tglx: Split out from larger combo patch. Add changelog. ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.077004842@linutronix.de

kernel/sched/core.c

@@ -255,7 +255,7 @@ static void __hrtick_restart(struct rq *rq)
 {
 	struct hrtimer *timer = &rq->hrtick_timer;
 
-	hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED);
+	hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD);
 }
 
 /*
@@ -314,7 +314,7 @@ void hrtick_start(struct rq *rq, u64 delay)
 	 */
 	delay = max_t(u64, delay, 10000LL);
 	hrtimer_start(&rq->hrtick_timer, ns_to_ktime(delay),
-		      HRTIMER_MODE_REL_PINNED);
+		      HRTIMER_MODE_REL_PINNED_HARD);
 }
 #endif /* CONFIG_SMP */
 
@@ -328,7 +328,7 @@ static void hrtick_rq_init(struct rq *rq)
 	rq->hrtick_csd.info = rq;
 #endif
 
-	hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD);
 	rq->hrtick_timer.function = hrtick;
 }
 #else	/* CONFIG_SCHED_HRTICK */

kernel/sched/deadline.c

@@ -923,7 +923,7 @@ static int start_dl_timer(struct task_struct *p)
 	 */
 	if (!hrtimer_is_queued(timer)) {
 		get_task_struct(p);
-		hrtimer_start(timer, act, HRTIMER_MODE_ABS);
+		hrtimer_start(timer, act, HRTIMER_MODE_ABS_HARD);
 	}
 
 	return 1;
@@ -1053,7 +1053,7 @@ void init_dl_task_timer(struct sched_dl_entity *dl_se)
 {
 	struct hrtimer *timer = &dl_se->dl_timer;
 
-	hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD);
 	timer->function = dl_task_timer;
 }
 

kernel/sched/rt.c

@@ -45,8 +45,8 @@ void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime)
 
 	raw_spin_lock_init(&rt_b->rt_runtime_lock);
 
-	hrtimer_init(&rt_b->rt_period_timer,
-			CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hrtimer_init(&rt_b->rt_period_timer, CLOCK_MONOTONIC,
+		     HRTIMER_MODE_REL_HARD);
 	rt_b->rt_period_timer.function = sched_rt_period_timer;
 }
 
@@ -67,7 +67,8 @@ static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
 		 * to update the period.
 		 */
 		hrtimer_forward_now(&rt_b->rt_period_timer, ns_to_ktime(0));
-		hrtimer_start_expires(&rt_b->rt_period_timer, HRTIMER_MODE_ABS_PINNED);
+		hrtimer_start_expires(&rt_b->rt_period_timer,
+				      HRTIMER_MODE_ABS_PINNED_HARD);
 	}
 	raw_spin_unlock(&rt_b->rt_runtime_lock);
 }