[PATCH V2 2/2] tools/perf/tests: perf all metricgroups test fails when perf_event access is restricted

[Athira Rajeev <atrajeev@linux.vnet.ibm.com>]

Perf all metricgroups test fails as below when perf_event access
is restricted.

    ./perf test -v "perf all metricgroups test"
    Testing Memory_BW
    Error:
    Access to performance monitoring and observability operations is limited.
    Enforced MAC policy settings (SELinux) can limit access to performance
    access to performance monitoring and observability operations for processes
    without CAP_PERFMON, CAP_SYS_PTRACE or CAP_SYS_ADMIN Linux capability.

    test child finished with -1
    ---- end ----
    perf all metricgroups test: FAILED!

Fix the testcase to skip those metric events which needs perf_event access
explicitly. The exit code of the testcase is based on return code of
the perf stat command ( enabled by set -e option ). Hence save the
exit status in a variable and use that to decide success or fail for the
testcase.

Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
---
Changelog:
v1 -> v2:
 Changed the condition to use "echo" and "grep" so it works on
 Posix shell as well.

 tools/perf/tests/shell/stat_all_metricgroups.sh | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/tools/perf/tests/shell/stat_all_metricgroups.sh b/tools/perf/tests/shell/stat_all_metricgroups.sh
index cb35e488809a..eaa5e1172294 100755
--- a/tools/perf/tests/shell/stat_all_metricgroups.sh
+++ b/tools/perf/tests/shell/stat_all_metricgroups.sh
@@ -2,11 +2,19 @@
 # perf all metricgroups test
 # SPDX-License-Identifier: GPL-2.0
 
-set -e
-
 for m in $(perf list --raw-dump metricgroups); do
   echo "Testing $m"
-  perf stat -M "$m" -a true
+  result=$(perf stat -M "$m" -a true 2>&1)
+  rc=$?
+  # Skip if there is no access to perf_events monitoring
+  # Otherwise exit based on the return code of perf comamnd.
+  if echo "$result" | grep -q "Access to performance monitoring and observability operations is limited";
+  then
+      continue
+  else
+      [ $rc -ne 0 ] && exit $rc
+  fi
+
 done
 
 exit 0
-- 
2.31.1