The ARM PMU driver can be used to represent a variety of ARM based
PMUs. Some of these PMUs do not provide support for context
exclusion, where this is the case we advertise the
PERF_PMU_CAP_NO_EXCLUDE capability to ensure that perf prevents us
from handling events where any exclusion flags are set.
Where an ARM PMU driver has the set_event_filter function implemented,
we rely on it to perform exclusion checks. At present some of these
functions do not test for all of the available exclude flags.
Signed-off-by: Andrew Murray <andrew.mur...@arm.com>
Acked-by: Will Deacon <will.dea...@arm.com>
---
drivers/perf/arm_pmu.c | 15 +++++----------
1 file changed, 5 insertions(+), 10 deletions(-)
diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index d0b7dd8..eec75b9 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -357,13 +357,6 @@ static irqreturn_t armpmu_dispatch_irq(int irq, void *dev)
}
static int
-event_requires_mode_exclusion(struct perf_event_attr *attr)
-{
- return attr->exclude_idle || attr->exclude_user ||
- attr->exclude_kernel || attr->exclude_hv;
-}
-
-static int
__hw_perf_event_init(struct perf_event *event)
{
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
@@ -393,9 +386,8 @@ __hw_perf_event_init(struct perf_event *event)
/*
* Check whether we need to exclude the counter from certain modes.
*/
- if ((!armpmu->set_event_filter ||
- armpmu->set_event_filter(hwc, &event->attr)) &&
- event_requires_mode_exclusion(&event->attr)) {
+ if (armpmu->set_event_filter &&
+ armpmu->set_event_filter(hwc, &event->attr)) {
pr_debug("ARM performance counters do not support "
"mode exclusion\n");
return -EOPNOTSUPP;
@@ -867,6 +859,9 @@ int armpmu_register(struct arm_pmu *pmu)
if (ret)
return ret;
+ if (!pmu->set_event_filter)
+ pmu->pmu.capabilities |= PERF_PMU_CAP_NO_EXCLUDE;
+
ret = perf_pmu_register(&pmu->pmu, pmu->name, -1);
if (ret)
goto out_destroy;
--
2.7.4
