On 2020-02-21 15:24:31 [-0600], zanussi@xxxxxxxxxx wrote: > [ Upstream commit ba94e7aed7405c58251b1380e6e7d73aa8284b41 ] > > SCHED_DEADLINE inactive timer needs to run in hardirq context (as > dl_task_timer already does) on PREEMPT_RT The message says "dl_task_timer already does" but this is not true for v4.14 as it still runs in softirq context on RT. v4.19 has this either via https://lkml.kernel.org/r/20190731103715.4047-1-juri.lelli@xxxxxxxxxx or the patch which got merged upstream. Juri, I guess we want this for v4.14, too? > 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@xxxxxxxxxx> > Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Link: https://lkml.kernel.org/r/20190731103715.4047-1-juri.lelli@xxxxxxxxxx > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> > Signed-off-by: Tom Zanussi <zanussi@xxxxxxxxxx> > --- > kernel/sched/deadline.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c > index eb68f7fb8a36..7b04e54bea01 100644 > --- a/kernel/sched/deadline.c > +++ b/kernel/sched/deadline.c > @@ -252,7 +252,7 @@ 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) > @@ -1234,7 +1234,7 @@ 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; > } > Sebastian
