sched/deadline: Ensure inactive_timer runs in hardirq context

SCHED_DEADLINE inactive timer needs to run in hardirq context (as
dl_task_timer already does) on PREEMPT_RT

Change the mode to HRTIMER_MODE_REL_HARD.

[ tglx: Fixed up the start site, so mode debugging works ]

Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190731103715.4047-1-juri.lelli@redhat.com

diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 0359612d5443a25abc777f4dfb9f2a4f428dea12..83a663a34196b9a8288414223c3b7c241459be82 100644 (file)
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -287,7 +287,7 @@ static void task_non_contending(struct task_struct *p)
 
        dl_se->dl_non_contending = 1;
        get_task_struct(p);
-       hrtimer_start(timer, ns_to_ktime(zerolag_time), HRTIMER_MODE_REL);
+       hrtimer_start(timer, ns_to_ktime(zerolag_time), HRTIMER_MODE_REL_HARD);
 }
 
 static void task_contending(struct sched_dl_entity *dl_se, int flags)
@@ -1292,7 +1292,7 @@ void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se)
 {
        struct hrtimer *timer = &dl_se->inactive_timer;
 
-       hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+       hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD);
        timer->function = inactive_task_timer;
 }