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@vger.kernel.org Signed-off-by: Will Deacon will.deacon@arm.com
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@arm.com