perf evlist: Factor out evlist__dummy_event()

Factor out evlist__dummy_event() so it can be reused.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Link: https://lore.kernel.org/r/20220524075436.29144-5-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/evlist.c

@@ -242,14 +242,20 @@ int __evlist__add_default(struct evlist *evlist, bool precise)
 	return 0;
 }
 
-int evlist__add_dummy(struct evlist *evlist)
+static struct evsel *evlist__dummy_event(struct evlist *evlist)
 {
 	struct perf_event_attr attr = {
 		.type	= PERF_TYPE_SOFTWARE,
 		.config = PERF_COUNT_SW_DUMMY,
 		.size	= sizeof(attr), /* to capture ABI version */
 	};
-	struct evsel *evsel = evsel__new_idx(&attr, evlist->core.nr_entries);
+
+	return evsel__new_idx(&attr, evlist->core.nr_entries);
+}
+
+int evlist__add_dummy(struct evlist *evlist)
+{
+	struct evsel *evsel = evlist__dummy_event(evlist);
 
 	if (evsel == NULL)
 		return -ENOMEM;