perf intel-tpebs: Rename tpebs_start to evsel__tpebs_open

Try to add more consistency to evsel by having tpebs_start renamed to
evsel__tpebs_open, passing the evsel that is being opened. The unusual
behavior of evsel__tpebs_open opening all events on the evlist is kept
and will be cleaned up further in later patches. The comments are
cleaned up as tpebs_start isn't called from evlist.

Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Weilin Wang <weilin.wang@intel.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: Andreas Färber <afaerber@suse.de>
Cc: Caleb Biggers <caleb.biggers@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Perry Taylor <perry.taylor@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Link: https://lore.kernel.org/r/20250414174134.3095492-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

3 files changed, 18 insertions, 19 deletions

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 3c030da2e477..c29b93151158 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -2576,7 +2576,7 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
 	struct perf_cpu cpu;
 
 	if (evsel__is_retire_lat(evsel))
-		return tpebs_start(evsel->evlist);
+		return evsel__tpebs_open(evsel);
 
 	err = __evsel__prepare_open(evsel, cpus, threads);
 	if (err)
diff --git a/tools/perf/util/intel-tpebs.c b/tools/perf/util/intel-tpebs.c
index 74b43faab986..566e0ddcad88 100644
--- a/tools/perf/util/intel-tpebs.c
+++ b/tools/perf/util/intel-tpebs.c
@@ -12,6 +12,7 @@
 #include <linux/zalloc.h>
 #include <linux/err.h>
 #include "sample.h"
+#include "counts.h"
 #include "debug.h"
 #include "evlist.h"
 #include "evsel.h"
@@ -189,18 +190,16 @@ static int tpebs_stop(void)
 	return ret;
 }
 
-/*
- * tpebs_start - start tpebs execution.
- * @evsel_list: retire_latency evsels in this list will be selected and sampled
- * to get the average retire_latency value.
- *
- * This function will be called from evlist level later when evlist__open() is
- * called consistently.
+/**
+ * evsel__tpebs_open - starts tpebs execution.
+ * @evsel: retire_latency evsel, all evsels on its list will be selected. Each
+ *         evsel is sampled to get the average retire_latency value.
  */
-int tpebs_start(struct evlist *evsel_list)
+int evsel__tpebs_open(struct evsel *evsel)
 {
 	int ret = 0;
-	struct evsel *evsel;
+	struct evsel *pos;
+	struct evlist *evsel_list = evsel->evlist;
 	char cpumap_buf[50];
 
 	/*
@@ -215,25 +214,25 @@ int tpebs_start(struct evlist *evsel_list)
 	 * Prepare perf record for sampling event retire_latency before fork and
 	 * prepare workload
 	 */
-	evlist__for_each_entry(evsel_list, evsel) {
+	evlist__for_each_entry(evsel_list, pos) {
 		int i;
 		char *name;
 		struct tpebs_retire_lat *new;
 
-		if (!evsel->retire_lat)
+		if (!pos->retire_lat)
 			continue;
 
-		pr_debug("tpebs: Retire_latency of event %s is required\n", evsel->name);
-		for (i = strlen(evsel->name) - 1; i > 0; i--) {
-			if (evsel->name[i] == 'R')
+		pr_debug("tpebs: Retire_latency of event %s is required\n", pos->name);
+		for (i = strlen(pos->name) - 1; i > 0; i--) {
+			if (pos->name[i] == 'R')
 				break;
 		}
-		if (i <= 0 || evsel->name[i] != 'R') {
+		if (i <= 0 || pos->name[i] != 'R') {
 			ret = -1;
 			goto err;
 		}
 
-		name = strdup(evsel->name);
+		name = strdup(pos->name);
 		if (!name) {
 			ret = -ENOMEM;
 			goto err;
@@ -247,7 +246,7 @@ int tpebs_start(struct evlist *evsel_list)
 			goto err;
 		}
 		new->name = name;
-		new->tpebs_name = evsel->name;
+		new->tpebs_name = pos->name;
 		list_add_tail(&new->nd, &tpebs_results);
 		tpebs_event_size += 1;
 	}
diff --git a/tools/perf/util/intel-tpebs.h b/tools/perf/util/intel-tpebs.h
index 63c16e759a71..cc98203719c8 100644
--- a/tools/perf/util/intel-tpebs.h
+++ b/tools/perf/util/intel-tpebs.h
@@ -10,7 +10,7 @@ struct evsel;
 
 extern bool tpebs_recording;
 
-int tpebs_start(struct evlist *evsel_list);
+int evsel__tpebs_open(struct evsel *evsel);
 void tpebs_delete(void);
 int tpebs_set_evsel(struct evsel *evsel, int cpu_map_idx, int thread);