perf pmu: Add support for MetricName JSON attribute

Add support for a new JSON event attribute to name MetricExpr for better
output in perf stat.

If the event has no MetricName it uses the normal event name instead to
describe the metric.

Before

  % perf stat -a -I 1000 -e '{unc_p_clockticks,unc_p_freq_max_os_cycles}' --metric-only
           time unc_p_freq_max_os_cycles
     1.000149775     15.7
     2.000344807     19.3
     3.000502544     16.7
     4.000640656      6.6
     5.000779955      9.9

After

  % perf stat -a -I 1000 -e '{unc_p_clockticks,unc_p_freq_max_os_cycles}' --metric-only
           time freq_max_os_cycles %
     1.000149775     15.7
     2.000344807     19.3
     3.000502544     16.7
     4.000640656      6.6
     5.000779955      9.9

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-13-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

3 files changed, 14 insertions, 4 deletions

diff --git a/tools/perf/pmu-events/jevents.c b/tools/perf/pmu-events/jevents.c
index 0735dc2a167a..81f2ef3b15cf 100644
--- a/tools/perf/pmu-events/jevents.c
+++ b/tools/perf/pmu-events/jevents.c
@@ -292,7 +292,8 @@ static void print_events_table_prefix(FILE *fp, const char *tblname)
 static int print_events_table_entry(void *data, char *name, char *event,
 				    char *desc, char *long_desc,
 				    char *pmu, char *unit, char *perpkg,
-				    char *metric_expr)
+				    char *metric_expr,
+				    char *metric_name)
 {
 	struct perf_entry_data *pd = data;
 	FILE *outfp = pd->outfp;
@@ -318,6 +319,8 @@ static int print_events_table_entry(void *data, char *name, char *event,
 		fprintf(outfp, "\t.perpkg = \"%s\",\n", perpkg);
 	if (metric_expr)
 		fprintf(outfp, "\t.metric_expr = \"%s\",\n", metric_expr);
+	if (metric_name)
+		fprintf(outfp, "\t.metric_name = \"%s\",\n", metric_name);
 	fprintf(outfp, "},\n");
 
 	return 0;
@@ -366,7 +369,8 @@ int json_events(const char *fn,
 	  int (*func)(void *data, char *name, char *event, char *desc,
 		      char *long_desc,
 		      char *pmu, char *unit, char *perpkg,
-		      char *metric_expr),
+		      char *metric_expr,
+		      char *metric_name),
 	  void *data)
 {
 	int err = -EIO;
@@ -393,6 +397,7 @@ int json_events(const char *fn,
 		char *perpkg = NULL;
 		char *unit = NULL;
 		char *metric_expr = NULL;
+		char *metric_name = NULL;
 		unsigned long long eventcode = 0;
 		struct msrmap *msr = NULL;
 		jsmntok_t *msrval = NULL;
@@ -469,6 +474,8 @@ int json_events(const char *fn,
 				addfield(map, &unit, "", "", val);
 			} else if (json_streq(map, field, "PerPkg")) {
 				addfield(map, &perpkg, "", "", val);
+			} else if (json_streq(map, field, "MetricName")) {
+				addfield(map, &metric_name, "", "", val);
 			} else if (json_streq(map, field, "MetricExpr")) {
 				addfield(map, &metric_expr, "", "", val);
 				for (s = metric_expr; *s; s++)
@@ -497,7 +504,7 @@ int json_events(const char *fn,
 		fixname(name);
 
 		err = func(data, name, real_event(name, event), desc, long_desc,
-				pmu, unit, perpkg, metric_expr);
+				pmu, unit, perpkg, metric_expr, metric_name);
 		free(event);
 		free(desc);
 		free(name);
@@ -508,6 +515,7 @@ int json_events(const char *fn,
 		free(perpkg);
 		free(unit);
 		free(metric_expr);
+		free(metric_name);
 		if (err)
 			break;
 		tok += j;
diff --git a/tools/perf/pmu-events/jevents.h b/tools/perf/pmu-events/jevents.h
index 57e111bf2168..611fac01913d 100644
--- a/tools/perf/pmu-events/jevents.h
+++ b/tools/perf/pmu-events/jevents.h
@@ -5,7 +5,8 @@ int json_events(const char *fn,
 		int (*func)(void *data, char *name, char *event, char *desc,
 				char *long_desc,
 				char *pmu,
-				char *unit, char *perpkg, char *metric_expr),
+				char *unit, char *perpkg, char *metric_expr,
+				char *metric_name),
 		void *data);
 char *get_cpu_str(void);
 
diff --git a/tools/perf/pmu-events/pmu-events.h b/tools/perf/pmu-events/pmu-events.h
index d046e3a4ce46..569eab3688dd 100644
--- a/tools/perf/pmu-events/pmu-events.h
+++ b/tools/perf/pmu-events/pmu-events.h
@@ -14,6 +14,7 @@ struct pmu_event {
 	const char *unit;
 	const char *perpkg;
 	const char *metric_expr;
+	const char *metric_name;
 };
 
 /*