diff --git a/tools/perf/tests/attr.c b/tools/perf/tests/attr.c
index 6fa84b7065cd..6e2feee8db2a 100644
--- a/tools/perf/tests/attr.c
+++ b/tools/perf/tests/attr.c
@@ -126,8 +126,6 @@ static int store_event(struct perf_event_attr *attr, pid_t pid, int cpu,
 	WRITE_ASS(sample_regs_user,   "llu");
 	WRITE_ASS(sample_stack_user,  PRIu32);
 
-	__WRITE_ASS(optional, "d", 0);
-
 	fclose(file);
 	return 0;
 }
diff --git a/tools/perf/tests/attr.py b/tools/perf/tests/attr.py
index 28c0481bc984..9b25b33cf3e9 100644
--- a/tools/perf/tests/attr.py
+++ b/tools/perf/tests/attr.py
@@ -75,6 +75,7 @@ class Event(dict):
         self.add(data)
 
     def compare_data(self, a, b):
+        # Allow multiple values in assignment separated by '|'
         a_list = a.split('|')
         b_list = b.split('|')
 
@@ -96,12 +97,17 @@ class Event(dict):
                 return False
         return True
 
-    def is_optional(self):
-        if self['optional'] == '1':
-            return True
-        else:
-            return False
-
+# Test file description needs to have following sections:
+# [config]
+#   - just single instance in file
+#   - needs to specify:
+#     'command' - perf command name
+#     'args'    - special command arguments
+#     'ret'     - expected command return value (0 by default)
+#
+# [eventX:base]
+#   - one or multiple instances in file
+#   - expected values assignments
 class Test(object):
     def __init__(self, path, options):
         parser = ConfigParser.SafeConfigParser()
@@ -135,11 +141,15 @@ class Test(object):
         parser_event = ConfigParser.SafeConfigParser()
         parser_event.read(path)
 
+        # The event record section header contains 'event' word,
+        # optionaly followed by ':' allowing to load 'parent
+        # event' first as a base
         for section in filter(self.is_event, parser_event.sections()):
 
             parser_items = parser_event.items(section);
             base_items   = {}
 
+            # Read parent event if there's any
             if (':' in section):
                 base = section[section.index(':') + 1:]
                 parser_base = ConfigParser.SafeConfigParser()
@@ -177,11 +187,10 @@ class Test(object):
                 else:
                     log.debug("    ->FAIL");
 
-            log.info("    match: [%s] optional(%d) matches %s" %
-                      (exp_name, exp_event.is_optional(), str(exp_list)))
+            log.info("    match: [%s] matches %s" % (exp_name, str(exp_list)))
 
             # we did not any matching event - fail
-            if (not exp_list) and (not exp_event.is_optional()):
+            if (not exp_list):
                 raise Fail(self, 'match failure');
 
             match[exp_name] = exp_list
@@ -194,8 +203,6 @@ class Test(object):
             if (group == ''):
                 continue
 
-            # XXX group matching does not account for
-            # optional events as above matching does
             for res_name in match[exp_name]:
                 res_group = result[res_name].group
                 if res_group not in match[group]:
diff --git a/tools/perf/tests/attr/base-record b/tools/perf/tests/attr/base-record
index 8262794734e0..f1485d8e6a0b 100644
--- a/tools/perf/tests/attr/base-record
+++ b/tools/perf/tests/attr/base-record
@@ -37,4 +37,3 @@ config2=0
 branch_sample_type=0
 sample_regs_user=0
 sample_stack_user=0
-optional=0
diff --git a/tools/perf/tests/attr/base-stat b/tools/perf/tests/attr/base-stat
index 46f8851eaf4e..4bd79a82784f 100644
--- a/tools/perf/tests/attr/base-stat
+++ b/tools/perf/tests/attr/base-stat
@@ -37,4 +37,3 @@ config2=0
 branch_sample_type=0
 sample_regs_user=0
 sample_stack_user=0
-optional=0