perf python: Add PMU argument to parse_metrics

Add an optional PMU argument to parse_metrics to allow restriction of
the particular metrics to be opened. If no argument is provided then
all metrics with the given name/group are opened

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Gautam Menghani <gautam@linux.ibm.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Author: captain5050

tools/perf/util/python.c

@@ -2051,22 +2051,22 @@ static PyObject *pyrf__parse_events(PyObject *self, PyObject *args)
 
 static PyObject *pyrf__parse_metrics(PyObject *self, PyObject *args)
 {
-	const char *input;
+	const char *input, *pmu = NULL;
 	struct evlist evlist = {};
 	PyObject *result;
 	PyObject *pcpus = NULL, *pthreads = NULL;
 	struct perf_cpu_map *cpus;
 	struct perf_thread_map *threads;
 	int ret;
 
-	if (!PyArg_ParseTuple(args, "s|OO", &input, &pcpus, &pthreads))
+	if (!PyArg_ParseTuple(args, "s|sOO", &input, &pmu, &pcpus, &pthreads))
 		return NULL;
 
 	threads = pthreads ? ((struct pyrf_thread_map *)pthreads)->threads : NULL;
 	cpus = pcpus ? ((struct pyrf_cpu_map *)pcpus)->cpus : NULL;
 
 	evlist__init(&evlist, cpus, threads);
-	ret = metricgroup__parse_groups(&evlist, /*pmu=*/"all", input,
+	ret = metricgroup__parse_groups(&evlist, pmu ?: "all", input,
 					/*metric_no_group=*/ false,
 					/*metric_no_merge=*/ false,
 					/*metric_no_threshold=*/ true,