[PATCH v3 05/46] perf parse-events: Don't reorder ungrouped events by pmu

[Ian Rogers]

The pmu_group_name by default returns "cpu" which on non-hybrid/ARM
means that ungrouped software, and hardware events are all going to
sort by the original insertion index. However, on hybrid and ARM
wildcard expansion may mean the PMU name is set and events will be
unnecessarily reordered - triggering the reordering warning.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
 tools/perf/util/parse-events.c | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index d71019dcd614..34ba840ae19a 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -2140,25 +2140,32 @@ static int evlist__cmp(void *state, const struct list_head *l, const struct list
 	int *leader_idx = state;
 	int lhs_leader_idx = *leader_idx, rhs_leader_idx = *leader_idx, ret;
 	const char *lhs_pmu_name, *rhs_pmu_name;
+	bool lhs_has_group = false, rhs_has_group = false;
 
 	/*
 	 * First sort by grouping/leader. Read the leader idx only if the evsel
 	 * is part of a group, as -1 indicates no group.
 	 */
-	if (lhs_core->leader != lhs_core || lhs_core->nr_members > 1)
+	if (lhs_core->leader != lhs_core || lhs_core->nr_members > 1) {
+		lhs_has_group = true;
 		lhs_leader_idx = lhs_core->leader->idx;
-	if (rhs_core->leader != rhs_core || rhs_core->nr_members > 1)
+	}
+	if (rhs_core->leader != rhs_core || rhs_core->nr_members > 1) {
+		rhs_has_group = true;
 		rhs_leader_idx = rhs_core->leader->idx;
+	}
 
 	if (lhs_leader_idx != rhs_leader_idx)
 		return lhs_leader_idx - rhs_leader_idx;
 
-	/* Group by PMU. Groups can't span PMUs. */
-	lhs_pmu_name = evsel__group_pmu_name(lhs);
-	rhs_pmu_name = evsel__group_pmu_name(rhs);
-	ret = strcmp(lhs_pmu_name, rhs_pmu_name);
-	if (ret)
-		return ret;
+	/* Group by PMU if there is a group. Groups can't span PMUs. */
+	if (lhs_has_group && rhs_has_group) {
+		lhs_pmu_name = evsel__group_pmu_name(lhs);
+		rhs_pmu_name = evsel__group_pmu_name(rhs);
+		ret = strcmp(lhs_pmu_name, rhs_pmu_name);
+		if (ret)
+			return ret;
+	}
 
 	/* Architecture specific sorting. */
 	return arch_evlist__cmp(lhs, rhs);
-- 
2.40.1.495.gc816e09b53d-goog