Re: [PATCH] perf tools: Fix pmu events parsing rule
From: Arnaldo Carvalho de Melo
Date: Tue Jun 05 2018 - 09:25:20 EST
Em Tue, Jun 05, 2018 at 02:14:16PM +0200, Jiri Olsa escreveu:
> 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@xxxxxxxxx>
> Link: http://lkml.kernel.org/n/tip-vgf5a8wk0eyayo7omvutwhqo@xxxxxxxxxxxxxx
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Thanks, applied to acme/perf/core, will let it brew there for a while,
if we have time then I'll try getting it to perf/urgent, better error
messages are important :-)
- Arnaldo
> ---
> 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 <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;
> --
> 2.13.6