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ARM: perf: Remove unnecessary armpmu->enable()s

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Currently, armpmu_enable iterates through the events for a given
counter set, calling armpmu->enable on each before calling
armpmu->start to start the PMU's counters.

As armpmu->enable is called when each event is added, each event is
already configured in hardware. Due to this, calling armpmu->enable
in armpmu_enable is unnecessary and confusing.

This patch removes the unnecessary calls to armpmu->enable.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Mark Rutland
2011-08-23 11:59:49 +01:00
committed by Will Deacon
parent 0ce47080df
commit 7325eaec43
1 changed files with 2 additions and 12 deletions
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14
arch/arm/kernel/perf_event.c
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@@ -12,6 +12,7 @@
*/ */
#define pr_fmt(fmt) "hw perfevents: " fmt #define pr_fmt(fmt) "hw perfevents: " fmt
#include <linux/bitmap.h>
#include <linux/interrupt.h> #include <linux/interrupt.h>
#include <linux/kernel.h> #include <linux/kernel.h>
#include <linux/module.h> #include <linux/module.h>
@@ -557,20 +558,9 @@ static int armpmu_event_init(struct perf_event *event)
static void armpmu_enable(struct pmu *pmu) static void armpmu_enable(struct pmu *pmu)
{ {
/* Enable all of the perf events on hardware. */
struct arm_pmu *armpmu = to_arm_pmu(pmu); struct arm_pmu *armpmu = to_arm_pmu(pmu);
int idx, enabled = 0;
struct pmu_hw_events *hw_events = armpmu->get_hw_events(); struct pmu_hw_events *hw_events = armpmu->get_hw_events();
int enabled = bitmap_weight(hw_events->used_mask, armpmu->num_events);
for (idx = 0; idx < armpmu->num_events; ++idx) {
struct perf_event *event = hw_events->events[idx];
if (!event)
continue;
armpmu->enable(&event->hw, idx);
enabled = 1;
}
if (enabled) if (enabled)
armpmu->start(); armpmu->start();