linux-kernel - [PATCH 2/3] perf stat: Update runtime using cpu-clock event

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Date:	Fri, 13 May 2016 15:01:02 +0900
From:	Namhyung Kim <namhyung@...nel.org>
To:	Arnaldo Carvalho de Melo <acme@...nel.org>
Cc:	Ingo Molnar <mingo@...nel.org>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	Jiri Olsa <jolsa@...nel.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Andi Kleen <andi@...stfloor.org>
Subject: [PATCH 2/3] perf stat: Update runtime using cpu-clock event

Currently only task-clock event updates the runtime_nsec so it cannot
show the metric when using cpu-clock events.  However cpu clock works
basically same as task-clock, so no need to not update the runtime IMHO.

Before:

  # perf stat -a -e cpu-clock,context-switches,page-faults,cycles sleep 0.1

    Performance counter stats for 'system wide':

         1217.759506      cpu-clock (msec)
                  93      context-switches
                  61      page-faults
          18,958,022      cycles

         0.101393794 seconds time elapsed

After:

   Performance counter stats for 'system wide':

         1220.471884      cpu-clock (msec)          #   12.013 CPUs utilized
                 118      context-switches          #    0.097 K/sec
                  59      page-faults               #    0.048 K/sec
          17,941,247      cycles                    #    0.015 GHz

         0.101594777 seconds time elapsed

Signed-off-by: Namhyung Kim <namhyung@...nel.org>
---
 tools/perf/util/stat-shadow.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
index 61200fcac5ef..aa9efe08762b 100644
--- a/tools/perf/util/stat-shadow.c
+++ b/tools/perf/util/stat-shadow.c
@@ -94,7 +94,8 @@ void perf_stat__update_shadow_stats(struct perf_evsel *counter, u64 *count,
 {
 	int ctx = evsel_context(counter);
 
-	if (perf_evsel__match(counter, SOFTWARE, SW_TASK_CLOCK))
+	if (perf_evsel__match(counter, SOFTWARE, SW_TASK_CLOCK) ||
+	    perf_evsel__match(counter, SOFTWARE, SW_CPU_CLOCK))
 		update_stats(&runtime_nsecs_stats[cpu], count[0]);
 	else if (perf_evsel__match(counter, HARDWARE, HW_CPU_CYCLES))
 		update_stats(&runtime_cycles_stats[ctx][cpu], count[0]);
@@ -444,7 +445,8 @@ void perf_stat__print_shadow_stats(struct perf_evsel *evsel,
 			ratio = total / avg;
 
 		print_metric(ctxp, NULL, "%8.0f", "cycles / elision", ratio);
-	} else if (perf_evsel__match(evsel, SOFTWARE, SW_TASK_CLOCK)) {
+	} else if (perf_evsel__match(evsel, SOFTWARE, SW_TASK_CLOCK) ||
+		   perf_evsel__match(evsel, SOFTWARE, SW_CPU_CLOCK)) {
 		if ((ratio = avg_stats(&walltime_nsecs_stats)) != 0)
 			print_metric(ctxp, NULL, "%8.3f", "CPUs utilized",
 				     avg / ratio);
-- 
2.8.2