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Subject[PATCH] perf/arm-cci: Remove unnecessary period adjustment
Date
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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