[PATCH 2/3] perf/arm-cci: Remove pointless PMU disabling

From: Robin Murphy
Date: Fri May 11 2018 - 10:29:52 EST


The CCI PMU driver bears some legacy remnants of the arm_pmu framework
from when it was split in c6f85cb4305b ("bus: cci: move away from
arm_pmu framework"). In particular this perf_pmu_{dis,en}able() dance
around pmu->add which was fixed for arm_pmu in a9e469d1c89b
("drivers/perf: arm_pmu: remove pointless PMU disabling").

For the exact same reasons (i.e. perf core already does this around the
call anyway), give cci_pmu_add() the exact same change, which also
prevents having to export those core functions to build it as a module.

Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
---
drivers/perf/arm-cci.c | 13 +++----------
1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/drivers/perf/arm-cci.c b/drivers/perf/arm-cci.c
index 53c774b20563..7029d8fe8f44 100644
--- a/drivers/perf/arm-cci.c
+++ b/drivers/perf/arm-cci.c
@@ -1184,16 +1184,11 @@ static int cci_pmu_add(struct perf_event *event, int flags)
struct cci_pmu_hw_events *hw_events = &cci_pmu->hw_events;
struct hw_perf_event *hwc = &event->hw;
int idx;
- int err = 0;
-
- perf_pmu_disable(event->pmu);

/* If we don't have a space for the counter then finish early. */
idx = pmu_get_event_idx(hw_events, event);
- if (idx < 0) {
- err = idx;
- goto out;
- }
+ if (idx < 0)
+ return idx;

event->hw.idx = idx;
hw_events->events[idx] = event;
@@ -1205,9 +1200,7 @@ static int cci_pmu_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 void cci_pmu_del(struct perf_event *event, int flags)
--
2.17.0.dirty