[PATCH] perf tests record: allow for some difference in cycle count in leader sampling test on aarch64

[Anubhav Shelat <ashelat@redhat.com>]

On aarch64 systems, when running the leader sampling test, the cycle
count on the leader is consistently ~30 cycles less than the cycle count
on the slave event causing the test to fail. This looks like the result
of some hardware property of aarch64 processors, so allow for a small
difference in cycles between the leader and slave events on aarch64
systems.

Signed-off-by: Anubhav Shelat <ashelat@redhat.com>
---
 tools/perf/tests/shell/record.sh | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/tools/perf/tests/shell/record.sh b/tools/perf/tests/shell/record.sh
index b1ad24fb3b33..dff83d64e970 100755
--- a/tools/perf/tests/shell/record.sh
+++ b/tools/perf/tests/shell/record.sh
@@ -280,7 +280,12 @@ test_leader_sampling() {
   while IFS= read -r line
   do
     cycles=$(echo $line | awk '{for(i=1;i<=NF;i++) if($i=="cycles:") print $(i-1)}')
-    if [ $(($index%2)) -ne 0 ] && [ ${cycles}x != ${prev_cycles}x ]
+    # On aarch64 systems the leader event gets stopped ~30 cycles before the slave, so allow some
+    # difference
+    if [ "$(uname -m)" = "aarch64" ] && (( cycles - prev_cycles < 50 ))
+    then
+	    valid_counts=$(($valid_counts+1))
+    elif [ $(($index%2)) -ne 0 ] && [ ${cycles}x != ${prev_cycles}x ]
     then
       invalid_counts=$(($invalid_counts+1))
     else
-- 
2.47.3