@@ -431,6 +431,17 @@ static int smmu_pmu_event_init(struct perf_event *event)
return -EINVAL;
}
+ /*
+ * Ensure all events are on the same cpu so all events are in the
+ * same cpu context, to avoid races on pmu_enable etc.
+ */
+ event->cpu = smmu_pmu->on_cpu;
+
+ hwc->idx = -1;
+
+ if (event->group_leader == event)
+ return 0;
+
for_each_sibling_event(sibling, event->group_leader) {
if (is_software_event(sibling))
continue;
@@ -442,14 +453,6 @@ static int smmu_pmu_event_init(struct perf_event *event)
return -EINVAL;
}
- hwc->idx = -1;
-
- /*
- * Ensure all events are on the same cpu so all events are in the
- * same cpu context, to avoid races on pmu_enable etc.
- */
- event->cpu = smmu_pmu->on_cpu;
-
return 0;
}
Same as https://lore.kernel.org/all/20240514180050.182454-1-namhyung@kernel.org/, we should skip `for_each_sibling_event()` for group leader since it doesn't have the ctx yet. Fixes: f3c0eba28704 ("perf: Add a few assertions") Reported-by: Greg Thelen <gthelen@google.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Tuan Phan <tuanphan@os.amperecomputing.com> Signed-off-by: Chun-Tse Shao <ctshao@google.com> --- drivers/perf/arm_smmuv3_pmu.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-)