Commit 7325eaec authored by Mark Rutland's avatar Mark Rutland Committed by Will Deacon

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

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: default avatarMark Rutland <>
Signed-off-by: default avatarWill Deacon <>
parent 0ce47080
...@@ -12,6 +12,7 @@ ...@@ -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) ...@@ -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)
armpmu->enable(&event->hw, idx);
enabled = 1;
if (enabled) if (enabled)
armpmu->start(); armpmu->start();
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