perf tools: Fix pmu events parsing rule

Currently all the event parsing fails end up in the event_pmu rule, and display misleading help like:

  $ perf stat -e inst kill
  event syntax error: 'inst'
                       \___ Cannot find PMU `inst'. Missing kernel support?
  ...

The reason is that the event_pmu is too strong and match also single string. Changing it to force the '/' separators to be part of the rule, and getting the proper error now:

  $ perf stat -e inst kill
  event syntax error: 'inst'
                       \___ parser error
  Run 'perf list' for a list of valid events
  ...

Suggested-by Adrian Hunter <[email protected]>

Link http://lkml.kernel.org/n/[email protected] open here

Signed-off-by Jiri Olsa <[email protected]>

---
 tools/perf/util/parse-events.y | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

tools/perf/util/parse-events.y +13 -1

index e37608a87dba..155d2570274f 100644
@@ -73,6 +73,7 @@ static void inc_group_count(struct list_head *list,
 %type <num> value_sym
 %type <head> event_config
 %type <head> opt_event_config
+%type <head> opt_pmu_config
 %type <term> event_term
 %type <head> event_pmu
 %type <head> event_legacy_symbol

@@ -224,7 +225,7 @@ event_def: event_pmu |
 	   event_bpf_file
 
 event_pmu:
-PE_NAME opt_event_config
+PE_NAME opt_pmu_config
 {
 	struct list_head *list, *orig_terms, *terms;
 

@@ -496,6 +497,17 @@ opt_event_config:
 	$$ = NULL;
 }
 
+opt_pmu_config:
+'/' event_config '/'
+{
+	$$ = $2;
+}
+|
+'/' '/'
+{
+	$$ = NULL;
+}
+
 start_terms: event_config
 {
 	struct parse_events_state *parse_state = _parse_state;

Signature · 1 line

2.13.6