perf stat: Add noise output for csv mode

Previously, when you want perf-stat to output the statistics in
csv mode, no information of the noise will be printed out.

For example right now we output this --repeat information:

 ./perf stat -r3 -x, sleep 1
 1.164789,task-clock
 8,context-switches
 0,CPU-migrations
 219,page-faults
 3337800,cycles

With this patch, the output will be appended with an additional
entry for the noise value:

 ./perf stat -r3 -x, sleep 1
 1.164789,task-clock,3.75%
 8,context-switches,75.00%
 0,CPU-migrations,100.00%
 219,page-faults,0.00%
 3337800,cycles,3.36%

Signed-off-by: Zhengyu He <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Venkatesh Pallipadi <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

1 files changed, 6 insertions, 3 deletions

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 784ed6d6e0d6..1d08c8084cc4 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -517,7 +517,10 @@ static void print_noise_pct(double total, double avg)
 	if (avg)
 		pct = 100.0*total/avg;
 
-	fprintf(stderr, "  ( +-%6.2f%% )", pct);
+	if (csv_output)
+		fprintf(stderr, "%s%.2f%%", csv_sep, pct);
+	else
+		fprintf(stderr, "  ( +-%6.2f%% )", pct);
 }
 
 static void print_noise(struct perf_evsel *evsel, double avg)
@@ -882,13 +885,13 @@ static void print_counter_aggr(struct perf_evsel *counter)
 	else
 		abs_printout(-1, counter, avg);
 
+	print_noise(counter, avg);
+
 	if (csv_output) {
 		fputc('\n', stderr);
 		return;
 	}
 
-	print_noise(counter, avg);
-
 	if (scaled) {
 		double avg_enabled, avg_running;