[PATCH 2/3] perf test: Fix record tests on Intel Broadwell

[Namhyung Kim <namhyung@kernel.org>]

I noticed it failed for leader sampling tests on Broadwell.  It's
because the period of groups members are a little bit different.  Maybe
there's an hardware issue but anyway it's close enough to treat them as
same.  I printed the value like below.

  $ perf test record
  ...
  prev: 462507, curr: 462506
  prev: 494783, curr: 494782
  prev: 454350, curr: 454349
  prev: 502782, curr: 502781
  prev: 566693, curr: 566692
  prev: 606558, curr: 606557
  prev: 559770, curr: 559769
  prev: 595737, curr: 595736
  prev: 643386, curr: 643385
  prev: 663672, curr: 663671
  prev: 620622, curr: 620621
  prev: 650419, curr: 650418
  Leader sampling [Failed inconsistent cycles count]

Let's update the logic to compare values to allow 1% of errors.

Also I think it should compare only if sees the non-leader samples so
split the check of (($index % 2)).

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/tests/shell/record.sh | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/tools/perf/tests/shell/record.sh b/tools/perf/tests/shell/record.sh
index cf8ba3d3411b0bcc..04df35b30b0c15fd 100755
--- a/tools/perf/tests/shell/record.sh
+++ b/tools/perf/tests/shell/record.sh
@@ -550,11 +550,14 @@ 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 ]
+    if [ $(($index%2)) -ne 0 ]
     then
-      invalid_counts=$(($invalid_counts+1))
-    else
-      valid_counts=$(($valid_counts+1))
+      if (( $(bc <<< "scale=4; r = ${cycles} / ${prev_cycles}; r >= 0.99 && r <= 1.01") ))
+      then
+        valid_counts=$(($valid_counts+1))
+      else
+        invalid_counts=$(($invalid_counts+1))
+      fi
     fi
     index=$(($index+1))
     prev_cycles=$cycles
-- 
2.56.0.rc1.310.g51773c2048-goog