perf evsel: Remove pmu_name

"evsel->pmu_name" is only ever assigned a strdup of "pmu->name", a
strdup of "evsel->pmu_name" or NULL. As such, prefer to use
"pmu->name" directly and even to directly compare PMUs than PMU
names. For safety, add some additional NULL tests.

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Ian Rogers <irogers@google.com>
[ Fix arm-spe.c usage of pmu_name and empty PMU name ]
Acked-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Cc: Yang Jihong <yangjihong@bytedance.com>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ze Gao <zegao2021@gmail.com>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Cc: Weilin Wang <weilin.wang@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Jing Zhang <renyu.zj@linux.alibaba.com>
Cc: Yang Li <yang.lee@linux.alibaba.com>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: ak@linux.intel.com
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Sun Haiyong <sunhaiyong@loongson.cn>
Cc: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20240926144851.245903-6-james.clark@linaro.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

7 files changed, 11 insertions, 19 deletions

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 7be0800b89d8..37d0fc01c180 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -2591,7 +2591,8 @@ void evlist__uniquify_name(struct evlist *evlist)
 		else
 			attributes = empty_attributes;
 
-		if (asprintf(&new_name, "%s/%s/%s", pos->pmu_name, pos->name, attributes + 1)) {
+		if (asprintf(&new_name, "%s/%s/%s", pos->pmu ? pos->pmu->name : "",
+			     pos->name, attributes + 1)) {
 			free(pos->name);
 			pos->name = new_name;
 		} else {
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index b9d7b56dfc5e..edfb376f0611 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -296,7 +296,6 @@ void evsel__init(struct evsel *evsel,
 	evsel->metric_events = NULL;
 	evsel->per_pkg_mask  = NULL;
 	evsel->collect_stat  = false;
-	evsel->pmu_name      = NULL;
 	evsel->group_pmu_name = NULL;
 	evsel->skippable     = false;
 	evsel->alternate_hw_config = PERF_COUNT_HW_MAX;
@@ -394,11 +393,6 @@ struct evsel *evsel__clone(struct evsel *orig)
 		if (evsel->group_name == NULL)
 			goto out_err;
 	}
-	if (orig->pmu_name) {
-		evsel->pmu_name = strdup(orig->pmu_name);
-		if (evsel->pmu_name == NULL)
-			goto out_err;
-	}
 	if (orig->group_pmu_name) {
 		evsel->group_pmu_name = strdup(orig->group_pmu_name);
 		if (evsel->group_pmu_name == NULL)
@@ -1497,7 +1491,6 @@ void evsel__exit(struct evsel *evsel)
 	zfree(&evsel->group_name);
 	zfree(&evsel->name);
 	zfree(&evsel->filter);
-	zfree(&evsel->pmu_name);
 	zfree(&evsel->group_pmu_name);
 	zfree(&evsel->unit);
 	zfree(&evsel->metric_id);
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index cf6f11fdfd06..3e751ea769ac 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -72,7 +72,6 @@ struct evsel {
 	struct {
 		char			*name;
 		char			*group_name;
-		const char		*pmu_name;
 		const char		*group_pmu_name;
 #ifdef HAVE_LIBTRACEEVENT
 		struct tep_event	*tp_format;
@@ -184,7 +183,7 @@ struct evsel {
 	unsigned long		open_flags;
 	int			precise_ip_original;
 
-	/* for missing_features */
+	/* The PMU the event is from. Used for missing_features, PMU name, etc. */
 	struct perf_pmu		*pmu;
 
 	/* For tool events */
diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
index 4dff3e925a47..9c6fa6b4f628 100644
--- a/tools/perf/util/metricgroup.c
+++ b/tools/perf/util/metricgroup.c
@@ -297,8 +297,8 @@ static int setup_metric_events(const char *pmu, struct hashmap *ids,
 		struct expr_id_data *val_ptr;
 
 		/* Don't match events for the wrong hybrid PMU. */
-		if (!all_pmus && ev->pmu_name && evsel__is_hybrid(ev) &&
-		    strcmp(ev->pmu_name, pmu))
+		if (!all_pmus && ev->pmu && evsel__is_hybrid(ev) &&
+		    strcmp(ev->pmu->name, pmu))
 			continue;
 		/*
 		 * Check for duplicate events with the same name. For
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index fcc4dab618be..e96cf13dc396 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -263,7 +263,6 @@ __add_event(struct list_head *list, int *idx,
 	evsel->core.is_pmu_core = pmu ? pmu->is_core : false;
 	evsel->auto_merge_stats = auto_merge_stats;
 	evsel->pmu = pmu;
-	evsel->pmu_name = pmu ? strdup(pmu->name) : NULL;
 	evsel->alternate_hw_config = alternate_hw_config;
 
 	if (name)
diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
index dd709a731574..3ce756b8ede5 100644
--- a/tools/perf/util/stat-shadow.c
+++ b/tools/perf/util/stat-shadow.c
@@ -573,7 +573,7 @@ static void perf_stat__print_metricgroup_header(struct perf_stat_config *config,
 {
 	bool need_full_name = perf_pmus__num_core_pmus() > 1;
 	static const char *last_name;
-	static const char *last_pmu;
+	static const struct perf_pmu *last_pmu;
 	char full_name[64];
 
 	/*
@@ -584,21 +584,21 @@ static void perf_stat__print_metricgroup_header(struct perf_stat_config *config,
 	 * different metric events.
 	 */
 	if (last_name && !strcmp(last_name, name)) {
-		if (!need_full_name || !strcmp(last_pmu, evsel->pmu_name)) {
+		if (!need_full_name || last_pmu != evsel->pmu) {
 			out->print_metricgroup_header(config, ctxp, NULL);
 			return;
 		}
 	}
 
-	if (need_full_name)
-		scnprintf(full_name, sizeof(full_name), "%s (%s)", name, evsel->pmu_name);
+	if (need_full_name && evsel->pmu)
+		scnprintf(full_name, sizeof(full_name), "%s (%s)", name, evsel->pmu->name);
 	else
 		scnprintf(full_name, sizeof(full_name), "%s", name);
 
 	out->print_metricgroup_header(config, ctxp, full_name);
 
 	last_name = name;
-	last_pmu = evsel->pmu_name;
+	last_pmu = evsel->pmu;
 }
 
 /**
diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c
index 0bd5467389e4..7c2ccdcc3fdb 100644
--- a/tools/perf/util/stat.c
+++ b/tools/perf/util/stat.c
@@ -553,7 +553,7 @@ static bool evsel__is_alias(struct evsel *evsel_a, struct evsel *evsel_b)
 	if (evsel__is_clock(evsel_a) != evsel__is_clock(evsel_b))
 		return false;
 
-	return !!strcmp(evsel_a->pmu_name, evsel_b->pmu_name);
+	return evsel_a->pmu != evsel_b->pmu;
 }
 
 static void evsel__merge_aliases(struct evsel *evsel)