[PATCH 38/46] perf tools: Fix pmu events parsing rule

Arnaldo Carvalho de Melo
2018-06-05T17:57:28Z

From: Jiri Olsa <jolsa@kernel.org>

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 <adrian.hunter@intel.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180605121416.31645-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/parse-events.y | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index e37608a87dba..155d2570274f 100644
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y
@@ -73,6 +73,7 @@ static void inc_group_count(struct list_head *list,
%type <num> value_sym
%type event_config
%type opt_event_config
+%type opt_pmu_config
%type <term> event_term
%type event_pmu
%type 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;
--
2.14.3