[PATCH 04/11] perf stat: Only print NMI watchdog hint when enabled

From: Arnaldo Carvalho de Melo
Date: Tue Jun 06 2017 - 15:29:12 EST


From: Andi Kleen <ak@xxxxxxxxxxxxxxx>

Only print the NMI watchdog hint when that watchdog it actually enabled.

This avoids printing these unnecessarily.

Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-lnw7edxnqsphkmeew857wz1i@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-stat.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index a935b5023732..ad9324d1daf9 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -1578,6 +1578,7 @@ static void print_header(int argc, const char **argv)
static void print_footer(void)
{
FILE *output = stat_config.output;
+ int n;

if (!null_run)
fprintf(output, "\n");
@@ -1590,7 +1591,9 @@ static void print_footer(void)
}
fprintf(output, "\n\n");

- if (print_free_counters_hint)
+ if (print_free_counters_hint &&
+ sysctl__read_int("kernel/nmi_watchdog", &n) >= 0 &&
+ n > 0)
fprintf(output,
"Some events weren't counted. Try disabling the NMI watchdog:\n"
" echo 0 > /proc/sys/kernel/nmi_watchdog\n"
--
2.9.4