psi: Fix trigger being fired unexpectedly at initial

When a trigger being created, its win.start_value and win.start_time are
reset to zero. If group->total[PSI_POLL][t->state] has accumulated before,
this trigger will be fired unexpectedly in the next period, even if its
growth time does not reach its threshold.

So set the window of the new trigger to the current state value.

Signed-off-by: Hailong Liu <liuhailong@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Suren Baghdasaryan <surenb@google.com>
Link: https://lore.kernel.org/r/1648789811-3788971-1-git-send-email-liuhailong@linux.alibaba.com
This commit is contained in:
Hailong Liu 2022-04-01 13:10:11 +08:00 committed by Peter Zijlstra
parent 089c02ae27
commit 915a087e4c

View File

@ -1117,7 +1117,8 @@ struct psi_trigger *psi_trigger_create(struct psi_group *group,
t->state = state;
t->threshold = threshold_us * NSEC_PER_USEC;
t->win.size = window_us * NSEC_PER_USEC;
window_reset(&t->win, 0, 0, 0);
window_reset(&t->win, sched_clock(),
group->total[PSI_POLL][t->state], 0);
t->event = 0;
t->last_event_time = 0;