perf tools: Add event_update event scale type

A__allocdding scale type 'event update' event, that stores/transfer
events scale value. The PMU events can define the scale
value which is used to multiply events data.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Kan Liang <kan.liang@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1445784728-21732-23-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/tests/event_update.c b/tools/perf/tests/event_update.c
index 9cdf4c9..a91fcef 100644
--- a/tools/perf/tests/event_update.c
+++ b/tools/perf/tests/event_update.c
@@ -18,6 +18,22 @@
 	return 0;
 }
 
+static int process_event_scale(struct perf_tool *tool __maybe_unused,
+			       union perf_event *event,
+			       struct perf_sample *sample __maybe_unused,
+			       struct machine *machine __maybe_unused)
+{
+	struct event_update_event *ev = (struct event_update_event *) event;
+	struct event_update_event_scale *ev_data;
+
+	ev_data = (struct event_update_event_scale *) ev->data;
+
+	TEST_ASSERT_VAL("wrong id", ev->id == 123);
+	TEST_ASSERT_VAL("wrong id", ev->type == PERF_EVENT_UPDATE__SCALE);
+	TEST_ASSERT_VAL("wrong scale", ev_data->scale = 0.123);
+	return 0;
+}
+
 int test__event_update(int subtest __maybe_unused)
 {
 	struct perf_evlist *evlist;
@@ -38,5 +54,10 @@
 	TEST_ASSERT_VAL("failed to synthesize attr update unit",
 			!perf_event__synthesize_event_update_unit(NULL, evsel, process_event_unit));
 
+	evsel->scale = 0.123;
+
+	TEST_ASSERT_VAL("failed to synthesize attr update scale",
+			!perf_event__synthesize_event_update_scale(NULL, evsel, process_event_scale));
+
 	return 0;
 }
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index 64c4cdf..44198e8 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -310,6 +310,11 @@
 
 enum {
 	PERF_EVENT_UPDATE__UNIT  = 0,
+	PERF_EVENT_UPDATE__SCALE = 1,
+};
+
+struct event_update_event_scale {
+	double scale;
 };
 
 struct event_update_event {
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 5759ebf..30edb4b 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -2723,6 +2723,27 @@
 	return err;
 }
 
+int
+perf_event__synthesize_event_update_scale(struct perf_tool *tool,
+					  struct perf_evsel *evsel,
+					  perf_event__handler_t process)
+{
+	struct event_update_event *ev;
+	struct event_update_event_scale *ev_data;
+	int err;
+
+	ev = event_update_event__new(sizeof(*ev_data), PERF_EVENT_UPDATE__SCALE, evsel->id[0]);
+	if (ev == NULL)
+		return -ENOMEM;
+
+	ev_data = (struct event_update_event_scale *) ev->data;
+	ev_data->scale = evsel->scale;
+	err = process(tool, (union perf_event*) ev, NULL, NULL);
+	free(ev);
+	return err;
+}
+
+
 int perf_event__synthesize_attrs(struct perf_tool *tool,
 				   struct perf_session *session,
 				   perf_event__handler_t process)
@@ -2787,6 +2808,7 @@
 				     struct perf_evlist **pevlist)
 {
 	struct event_update_event *ev = &event->event_update;
+	struct event_update_event_scale *ev_scale;
 	struct perf_evlist *evlist;
 	struct perf_evsel *evsel;
 
@@ -2802,6 +2824,10 @@
 	switch (ev->type) {
 	case PERF_EVENT_UPDATE__UNIT:
 		evsel->unit = strdup(ev->data);
+		break;
+	case PERF_EVENT_UPDATE__SCALE:
+		ev_scale = (struct event_update_event_scale *) ev->data;
+		evsel->scale = ev_scale->scale;
 	default:
 		break;
 	}
diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
index 6aa2b92..fad04cb 100644
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -108,6 +108,9 @@
 int perf_event__synthesize_event_update_unit(struct perf_tool *tool,
 					     struct perf_evsel *evsel,
 					     perf_event__handler_t process);
+int perf_event__synthesize_event_update_scale(struct perf_tool *tool,
+					      struct perf_evsel *evsel,
+					      perf_event__handler_t process);
 int perf_event__process_attr(struct perf_tool *tool, union perf_event *event,
 			     struct perf_evlist **pevlist);
 int perf_event__process_event_update(struct perf_tool *tool __maybe_unused,