drivers/perf: arm_pmu: remove pointless PMU disabling

We currently disable the PMU temporarily in armpmu_add(). We may have
required this historically, but the perf core always disables an event's
PMU when calling event::pmu::add(), so this is not necessary.

We don't do similarly in armpmu_del(), or elsewhere, so this is
unnecessary and inconsistent, and only serves to confuse the reader.

Remove the pointless disable, simplifying armpmu_add() in the process.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Mark Rutland 2017-04-11 09:39:44 +01:00 committed by Will Deacon
parent 3071f13d75
commit a9e469d1c8

View File

@ -235,20 +235,15 @@ armpmu_add(struct perf_event *event, int flags)
struct pmu_hw_events *hw_events = this_cpu_ptr(armpmu->hw_events);
struct hw_perf_event *hwc = &event->hw;
int idx;
int err = 0;
/* An event following a process won't be stopped earlier */
if (!cpumask_test_cpu(smp_processor_id(), &armpmu->supported_cpus))
return -ENOENT;
perf_pmu_disable(event->pmu);
/* If we don't have a space for the counter then finish early. */
idx = armpmu->get_event_idx(hw_events, event);
if (idx < 0) {
err = idx;
goto out;
}
if (idx < 0)
return idx;
/*
* If there is an event in the counter we are going to use then make
@ -265,9 +260,7 @@ armpmu_add(struct perf_event *event, int flags)
/* Propagate our changes to the userspace mapping. */
perf_event_update_userpage(event);
out:
perf_pmu_enable(event->pmu);
return err;
return 0;
}
static int