Messages in this thread Patch in this message | | | From | Robin Murphy <> | Subject | [PATCH] perf/arm-cci: Remove unnecessary period adjustment | Date | Mon, 21 May 2018 12:17:09 +0100 |
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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> --- drivers/perf/arm-cci.c | 9 --------- 1 file changed, 9 deletions(-)
diff --git a/drivers/perf/arm-cci.c b/drivers/perf/arm-cci.c index 09938dd8eb6f..e6fadc8e1178 100644 --- a/drivers/perf/arm-cci.c +++ b/drivers/perf/arm-cci.c @@ -1297,15 +1297,6 @@ 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; -- 2.17.0.dirty
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