Commit f28a439a authored Jun 17, 2019 by Patrick Daly

psi: Use deferrable psi_avgs_work



The logic for psi_avgs_work to not reschedule itself does not appear
to work properly.

1) psi_avgs_work detects itself as a running task due to accounting for
current states in get_recent_times().

2) Drivers with self-rescheduling deferrable work with a period
less than that of psi_avgs_work will always run when psi_avgs_work runs.
This causes psi_avgs_work to retrigger.

Make psi_avgs_work deferrable to avoid this loop.

Change-Id: I90edc5d3cce87ada803f549f417cd0108ef2017f
Signed-off-by: Patrick Daly <pdaly@codeaurora.org>

parent 297bbec9

kernel/sched/psi.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -189,7 +189,7 @@ static void group_init(struct psi_group *group)
		for_each_possible_cpu(cpu)
		seqcount_init(&per_cpu_ptr(group->pcpu, cpu)->seq);
		group->avg_next_update = sched_clock() + psi_period;
		INIT_DELAYED_WORK(&group->avgs_work, psi_avgs_work);
		INIT_DEFERRABLE_WORK(&group->avgs_work, psi_avgs_work);
		mutex_init(&group->avgs_lock);
		/* Init trigger-related members */
		atomic_set(&group->poll_scheduled, 0);