[PATCH 2/2] perf test: Fix JSON format linter test checks

[Michael Petlan <mpetlan@redhat.com>]

The test fails on CPUs with topdown metrics, where it is common to print
two metrics per line. Since these are included in default event set for
`perf stat -- something`, it causes the "no args" subtest to fail due to
unexpected member count. We need to accept 7 or 9 members in that case.

Coming to that, counting commas in the JSON line and consider it a number
of elements is incorrect and misleading. There should be +1 element than
the count of commas, while also, commas can potentially appear in the
event names. Count " : " substrings rather, since these better fit to
what should be actually counted.

Fixes: 0c343af2a2f8 ("perf test: JSON format checking")

Signed-off-by: Michael Petlan <mpetlan@redhat.com>
---
 .../tests/shell/lib/perf_json_output_lint.py     | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/tools/perf/tests/shell/lib/perf_json_output_lint.py b/tools/perf/tests/shell/lib/perf_json_output_lint.py
index d90f8d102eb9..4f1bbb3f07ec 100644
--- a/tools/perf/tests/shell/lib/perf_json_output_lint.py
+++ b/tools/perf/tests/shell/lib/perf_json_output_lint.py
@@ -40,17 +40,17 @@ def is_counter_value(num):
   return isfloat(num) or num == '<not counted>' or num == '<not supported>'
 
 def check_json_output(expected_items):
-  if expected_items != -1:
+  if expected_items:
     for line in Lines:
       if 'failed' not in line:
         count = 0
-        count = line.count(',')
-        if count != expected_items and count >= 1 and count <= 3 and 'metric-value' in line:
+        count = line.count(' : ')
+        if count not in expected_items and count >= 2 and count <= 4 and 'metric-value' in line:
           # Events that generate >1 metric may have isolated metric
           # values and possibly other prefixes like interval, core and
           # aggregate-number.
           continue
-        if count != expected_items:
+        if count not in expected_items:
           raise RuntimeError(f'wrong number of fields. counted {count} expected {expected_items}'
                              f' in \'{line}\'')
   checks = {
@@ -82,14 +82,14 @@ def check_json_output(expected_items):
 
 try:
   if args.no_args or args.system_wide or args.event:
-    expected_items = 6
+    expected_items = [7, 9]
   elif args.interval or args.per_thread or args.system_wide_no_aggr:
-    expected_items = 7
+    expected_items = [8, 10]
   elif args.per_core or args.per_socket or args.per_node or args.per_die:
-    expected_items = 8
+    expected_items = [9, 11]
   else:
     # If no option is specified, don't check the number of items.
-    expected_items = -1
+    expected_items = []
   check_json_output(expected_items)
 except:
   print('Test failed for input:\n' + '\n'.join(Lines))
-- 
2.18.4