perf parse-events: Use wildcard processing to set an event to merge into

The merge stat code fails for uncore events if they are repeated twice,
for example `perf stat -e clockticks,clockticks -I 1000` as the counts
of the second set of uncore events will be merged into the first
counter.

Reimplement the logic to have a first_wildcard_match so that merged
later events correctly merge into the first wildcard event that they
will be aggregated into.

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Chun-Tse Shao <ctshao@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Levi Yun <yeoreum.yun@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Weilin Wang <weilin.wang@intel.com>
Link: https://lore.kernel.org/r/20250513215401.2315949-3-ctshao@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 3 insertions, 37 deletions

diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c
index 1f7abd8754c7..355a7d5c8ab8 100644
--- a/tools/perf/util/stat.c
+++ b/tools/perf/util/stat.c
@@ -535,35 +535,6 @@ static int evsel__merge_aggr_counters(struct evsel *evsel, struct evsel *alias)
 
 	return 0;
 }
-/*
- * Events should have the same name, scale, unit, cgroup but on different core
- * PMUs or on different but matching uncore PMUs.
- */
-static bool evsel__is_alias(struct evsel *evsel_a, struct evsel *evsel_b)
-{
-	if (strcmp(evsel__name(evsel_a), evsel__name(evsel_b)))
-		return false;
-
-	if (evsel_a->scale != evsel_b->scale)
-		return false;
-
-	if (evsel_a->cgrp != evsel_b->cgrp)
-		return false;
-
-	if (strcmp(evsel_a->unit, evsel_b->unit))
-		return false;
-
-	if (evsel__is_clock(evsel_a) != evsel__is_clock(evsel_b))
-		return false;
-
-	if (evsel_a->pmu == evsel_b->pmu || evsel_a->pmu == NULL || evsel_b->pmu == NULL)
-		return false;
-
-	if (evsel_a->pmu->is_core)
-		return evsel_b->pmu->is_core;
-
-	return perf_pmu__name_no_suffix_match(evsel_a->pmu, evsel_b->pmu->name);
-}
 
 static void evsel__merge_aliases(struct evsel *evsel)
 {
@@ -572,10 +543,9 @@ static void evsel__merge_aliases(struct evsel *evsel)
 
 	alias = list_prepare_entry(evsel, &(evlist->core.entries), core.node);
 	list_for_each_entry_continue(alias, &evlist->core.entries, core.node) {
-		/* Merge the same events on different PMUs. */
-		if (evsel__is_alias(evsel, alias)) {
+		if (alias->first_wildcard_match == evsel) {
+			/* Merge the same events on different PMUs. */
 			evsel__merge_aggr_counters(evsel, alias);
-			alias->merged_stat = true;
 		}
 	}
 }
@@ -588,11 +558,7 @@ static bool evsel__should_merge_hybrid(const struct evsel *evsel,
 
 static void evsel__merge_stats(struct evsel *evsel, struct perf_stat_config *config)
 {
-	/* this evsel is already merged */
-	if (evsel->merged_stat)
-		return;
-
-	if (evsel->auto_merge_stats || evsel__should_merge_hybrid(evsel, config))
+	if (!evsel->pmu || !evsel->pmu->is_core || evsel__should_merge_hybrid(evsel, config))
 		evsel__merge_aliases(evsel);
 }