hrtimer_cancel
hrtimer_cancel(&adev->mode_info.crtcs[crtc]->vblank_timer);
hrtimer_cancel(&dev_priv->perf.oa.poll_check_timer);
hrtimer_cancel(&i915->pmu.timer);
WARN_ON(hrtimer_cancel(&d->timer));
if (hrtimer_cancel(&domain->timer) == 0)
extern int hrtimer_cancel(struct hrtimer *timer);