Commit 07c35320 authored by Ian Rogers's avatar Ian Rogers Committed by Arnaldo Carvalho de Melo
Browse files

perf intel-tpebs: Ensure events are opened, factor out finding 



Factor out finding an tpebs_retire_lat from an evsel.

Don't blindly return when ignoring an open request, which happens after
the first open request, ensure the event was started on a fork of perf
record.

Reviewed-by: default avatarKan Liang <kan.liang@linux.intel.com>
Signed-off-by: default avatarIan Rogers <irogers@google.com>
Tested-by: default avatarWeilin Wang <weilin.wang@intel.com>
Acked-by: default avatarNamhyung 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/20250414174134.3095492-9-irogers@google.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 84e62914

tools/perf/util/intel-tpebs.c

+37 −24
Original line number Diff line number Diff line
@@ -45,6 +45,8 @@ struct tpebs_retire_lat { 
	int sum;

	/* Average of retire_latency, val = sum / count */

	double val;

	/* Has the event been sent to perf record? */

	bool started;

};



static int evsel__tpebs_start_perf_record(struct evsel *evsel, int control_fd[], int ack_fd[])
@@ -94,6 +96,9 @@ static int evsel__tpebs_start_perf_record(struct evsel *evsel, int control_fd[], 
	tpebs_cmd.out = -1;

	ret = start_command(&tpebs_cmd);

	zfree(&tpebs_cmd.argv);

	list_for_each_entry(t, &tpebs_results, nd)

		t->started = true;



	return ret;

}
@@ -214,6 +219,19 @@ static struct tpebs_retire_lat *tpebs_retire_lat__new(struct evsel *evsel) 
	return result;

}



static struct tpebs_retire_lat *tpebs_retire_lat__find(struct evsel *evsel)

{

	struct tpebs_retire_lat *t;



	list_for_each_entry(t, &tpebs_results, nd) {

		if (t->tpebs_name == evsel->name ||

		    !strcmp(t->tpebs_name, evsel->name) ||

		    (evsel->metric_id && !strcmp(t->tpebs_name, evsel->metric_id)))

			return t;

	}

	return NULL;

}



/**

 * evsel__tpebs_prepare - create tpebs data structures ready for opening.

 * @evsel: retire_latency evsel, all evsels on its list will be prepared.
@@ -221,17 +239,12 @@ static struct tpebs_retire_lat *tpebs_retire_lat__new(struct evsel *evsel) 
static int evsel__tpebs_prepare(struct evsel *evsel)

{

	struct evsel *pos;

	struct tpebs_retire_lat *tpebs_event;

	struct tpebs_retire_lat *tpebs_event = tpebs_retire_lat__find(evsel);



	list_for_each_entry(tpebs_event, &tpebs_results, nd) {

		if (!strcmp(tpebs_event->tpebs_name, evsel->name)) {

			/*

			 * evsel, or an identically named one, was already

			 * prepared.

			 */

	if (tpebs_event) {

		/* evsel, or an identically named one, was already prepared. */

		return 0;

	}

	}

	tpebs_event = tpebs_retire_lat__new(evsel);

	if (!tpebs_event)

		return -ENOMEM;
@@ -262,12 +275,19 @@ int evsel__tpebs_open(struct evsel *evsel) 
{

	int ret;



	/*

	 * We should only run tpebs_start when tpebs_recording is enabled.

	 * And we should only run it once with all the required events.

	 */

	if (tpebs_cmd.pid != 0 || !tpebs_recording)

	/* We should only run tpebs_start when tpebs_recording is enabled. */

	if (!tpebs_recording)

		return 0;

	/* Only start the events once. */

	if (tpebs_cmd.pid != 0) {

		struct tpebs_retire_lat *t = tpebs_retire_lat__find(evsel);



		if (!t || !t->started) {

			/* Fail, as the event wasn't started. */

			return -EBUSY;

		}

		return 0;

	}



	ret = evsel__tpebs_prepare(evsel);

	if (ret)
@@ -352,7 +372,6 @@ int evsel__tpebs_open(struct evsel *evsel) 
int tpebs_set_evsel(struct evsel *evsel, int cpu_map_idx, int thread)

{

	__u64 val;

	bool found = false;

	struct tpebs_retire_lat *t;

	struct perf_counts_values *count;
@@ -367,19 +386,13 @@ int tpebs_set_evsel(struct evsel *evsel, int cpu_map_idx, int thread) 
	tpebs_stop();

	count = perf_counts(evsel->counts, cpu_map_idx, thread);



	list_for_each_entry(t, &tpebs_results, nd) {

		if (t->tpebs_name == evsel->name ||

		    (evsel->metric_id && !strcmp(t->tpebs_name, evsel->metric_id))) {

			found = true;

			break;

		}

	}

	t = tpebs_retire_lat__find(evsel);



	/* Set ena and run to non-zero */

	count->ena = count->run = 1;

	count->lost = 0;



	if (!found) {

	if (!t) {

		/*

		 * Set default value or 0 when retire_latency for this event is

		 * not found from sampling data (record_tpebs not set or 0