Hi Will
On 10/10/18 17:31, Will Deacon wrote:
It doesn't make sense for a perf event to be configured as a CHAIN event
in isolation, so extend the arm_pmu structure with a ->filter_match()
function to allow the backend PMU implementation to reject CHAIN events
early.
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
---
arch/arm64/kernel/perf_event.c | 7 +++++++
drivers/perf/arm_pmu.c | 8 +++++++-
include/linux/perf/arm_pmu.h | 1 +
3 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
index 8e38d5267f22..e213f8e867f6 100644
--- a/arch/arm64/kernel/perf_event.c
+++ b/arch/arm64/kernel/perf_event.c
@@ -966,6 +966,12 @@ static int armv8pmu_set_event_filter(struct hw_perf_event *event,
return 0;
}
+static int armv8pmu_filter_match(struct perf_event *event)
+{
+ unsigned long evtype = event->hw.config_base & ARMV8_PMU_EVTYPE_EVENT;
+ return evtype != ARMV8_PMUV3_PERFCTR_CHAIN;
+}
+
The patch looks correct. I guess we could handle it via the existing
map_event(), avoiding another arch specific callback.
Either way,
Reviewed-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
