perf/arm-cci: Remove unnecessary period adjustment (5c591304) · Commits · 戴 / test

Since sampling events are rejected up-front by cci_pmu_event_init(), it doesn't make much sense to go fiddling with the sampling period later. This would seem to be just another leftover artefact of the arm_pmu framwork, and as such can go. Acked-by:

Mark Rutland <mark.rutland@arm.com> Signed-off-by:

Robin Murphy <robin.murphy@arm.com> Signed-off-by:

Will Deacon <will.deacon@arm.com>

drivers/perf/arm-cci.c

+0 −9

Original line number	Diff line number	Diff line
		@@ -1304,15 +1304,6 @@ static int __hw_perf_event_init(struct perf_event *event)
		*/
		hwc->config_base \|= (unsigned long)mapping;

		/*
		* Limit the sample_period to half of the counter width. That way, the
		* new counter value is far less likely to overtake the previous one
		* unless you have some serious IRQ latency issues.
		*/
		hwc->sample_period = CCI_PMU_CNTR_MASK >> 1;
		hwc->last_period = hwc->sample_period;
		local64_set(&hwc->period_left, hwc->sample_period);

		if (event->group_leader != event) {
		if (validate_group(event) != 0)
		return -EINVAL;

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