[PATCH v2] perf test: perf stat tests fails on s390

[Thomas Richter]

The test case 'perf stat tests' fails on s390 z/VM machines. The
root cause is the unsupported CPU measurement facility on z/VM.
Therefore the events cycles and instructions do not exist and
are unsupported. This cause the subtest
  Hide zero events stat test
to fail.

Output before:
 # perf test 116
 116: perf stat tests  : FAILED!

 === Test Summary ===
 Passed main tests : 0
 Passed subtests   : 0
 Skipped tests     : 0
 Failed tests      : 1
 List of failed tests:
  116: perf stat tests
 #

Output after:
 # ./perf test 116
 116: perf stat tests  : Ok

 === Test Summary ===
 Passed main tests : 1
 Passed subtests   : 0
 Skipped tests     : 0
 Failed tests      : 0
 #

Fixes: 64724095a33f ("perf stat: Add --hide-zero-events option to suppress zero-count events")
Cc: Aaron Tomlin <atomlin@xxxxxxxxxxx>
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Signed-off-by: Thomas Richter <tmricht@xxxxxxxxxxxxx>
Reviewed-by: Aaron Tomlin <atomlin@xxxxxxxxxxx>
---
 tools/perf/tests/shell/stat.sh | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/tools/perf/tests/shell/stat.sh b/tools/perf/tests/shell/stat.sh
index 298ce454b45a..1f5d4cc05807 100755
--- a/tools/perf/tests/shell/stat.sh
+++ b/tools/perf/tests/shell/stat.sh
@@ -583,6 +583,11 @@ test_hide_zero_events_stat() {
   # Check that --metric-only works with --hide-zero-events
   if ! perf stat --hide-zero-events --metric-only -e instructions,cycles true > "${stat_output}" 2>&1
   then
+    if grep -sq 'No supported events found' "${stat_output}"
+    then
+      echo "Hide zero events stat test [Skipped - events not supported]"
+      return
+    fi
     echo "Hide zero events stat test [Failed - metric-only command failed]"
     err=1
     return
-- 
2.55.0