[PATCH 6.1 0763/1146] perf tools: Fix "kernel lock contention analysis" test by not printing warnings in quiet mode

Greg Kroah-Hartman
2022-12-28T16:28:47Z

From: James Clark <james.clark@arm.com>

[ Upstream commit 65319890c32db29fb56b41f84265a2c7029943f4 ]

Especially when CONFIG_LOCKDEP and other debug configs are enabled,
Perf can print the following warning when running the "kernel lock
contention analysis" test:

Warning:
Processed 1378918 events and lost 4 chunks!

Check IO/CPU overload!

Warning:
Processed 4593325 samples and lost 70.00%!

The test already supplies -q to run in quiet mode, so extend quiet mode
to perf_stdio__warning() and also ui__warning() for consistency.

This fixes the following failure due to the extra lines counted:

perf test "lock cont" -vvv

82: kernel lock contention analysis test :
--- start ---
test child forked, pid 3125
Testing perf lock record and perf lock contention
[Fail] Recorded result count is not 1: 9
test child finished with -1
---- end ----
kernel lock contention analysis test: FAILED!

Fixes: ec685de25b6718f8 ("perf test: Add kernel lock contention test")
Signed-off-by: James Clark <james.clark@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20221018094137.783081-2-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/perf/ui/util.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/tools/perf/ui/util.c b/tools/perf/ui/util.c
index 689b27c34246..1d38ddf01b60 100644
--- a/tools/perf/ui/util.c
+++ b/tools/perf/ui/util.c
@@ -15,6 +15,9 @@ static int perf_stdio__error(const char *format, va_list args)

static int perf_stdio__warning(const char *format, va_list args)
{
+ if (quiet)
+ return 0;
+
fprintf(stderr, "Warning:\n");
vfprintf(stderr, format, args);
return 0;
@@ -45,6 +48,8 @@ int ui__warning(const char *format, ...)
{
int ret;
va_list args;
+ if (quiet)
+ return 0;

va_start(args, format);
ret = perf_eops->warning(format, args);
--
2.35.1