[PATCH] perf test: Skip stat uniquifying test if unavailable

[Thomas Richter <tmricht@linux.ibm.com>]

Commit cb422594d6206 ("perf test: Add stat uniquifying test")
introduced a new test case which uses an event named clockticks
which is exported as sysfs file .../uncore_imc_0/clockticks.
This file does not exist on s390 and causes the test case to
always fail.

Check for the existence of file clockticks and skip this
test if the event does not exist.

Output before:
 #  perf test 87
 87: perf stat events uniquifying       : FAILED!
 # ./perf stat -e clockticks -A
   event syntax error: 'clockticks'
                        \___ Bad event name
   ...
 #

Output after:
 #  perf test 87
 87: perf stat events uniquifying       : Skip
 #

Fixes: cb422594d6206 ("perf test: Add stat uniquifying test")
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Chun-Tse Shao <ctshao@google.com>
---
 tools/perf/tests/shell/stat+event_uniquifying.sh | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/tools/perf/tests/shell/stat+event_uniquifying.sh b/tools/perf/tests/shell/stat+event_uniquifying.sh
index 5ec35c52b7d9..485ee6e8f574 100755
--- a/tools/perf/tests/shell/stat+event_uniquifying.sh
+++ b/tools/perf/tests/shell/stat+event_uniquifying.sh
@@ -49,6 +49,11 @@ test_event_uniquifying() {
     uniquified_event_array+=("${uniquified_event}")
   done < <(${perf_tool} list -v ${event} | grep "\[Kernel PMU event\]")
 
+  if [ -z "$uniquified_event" ]
+  then
+    err=2
+    return
+  fi
   perf_command="${perf_tool} stat -e $event -A -o ${stat_output} -- true"
   $perf_command
 
-- 
2.49.0