Commit 330bdf62 authored by Ben Skeggs's avatar Ben Skeggs

drm/nouveau/tmr: avoid processing completed alarms when adding a new one

The idea here was to avoid having to "manually" program the HW if there's
a new earliest alarm.  This was lazy and bad, as it leads to loads of fun
races between inter-related callers (ie. therm).

Turns out, it's not so difficult after all.  Go figure ;)
Signed-off-by: default avatarBen Skeggs <>
parent 9fc64667
......@@ -86,12 +86,22 @@ nvkm_timer_alarm(struct nvkm_timer *tmr, u32 nsec, struct nvkm_alarm *alarm)
if (list->timestamp > alarm->timestamp)
list_add_tail(&alarm->head, &list->head);
/* Update HW if this is now the earliest alarm. */
list = list_first_entry(&tmr->alarms, typeof(*list), head);
if (list == alarm) {
tmr->func->alarm_init(tmr, alarm->timestamp);
/* This shouldn't happen if callers aren't stupid.
* Worst case scenario is that it'll take roughly
* 4 seconds for the next alarm to trigger.
WARN_ON(alarm->timestamp <= nvkm_timer_read(tmr));
spin_unlock_irqrestore(&tmr->lock, flags);
/* process pending alarms */
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