Re: [PATCH 05/12] perf pmu: Fix pmu events parsing rule
From: Adrian Hunter
Date: Thu May 03 2018 - 04:26:34 EST
Hi
This breaks Intel PT i.e.
$ perf record -e intel_pt//u uname
event syntax error: 'intel_pt//u'
\___ parser error
Run 'perf list' for a list of valid events
Usage: perf record [<options>] [<command>]
or: perf record [<options>] -- <command> [<options>]
-e, --event <event> event selector. use 'perf list' to list available events
See below for cause.
On 25/04/18 19:00, Arnaldo Carvalho de Melo wrote:
> From: Jiri Olsa <jolsa@xxxxxxxxxx>
>
> 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
> ...
>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> Reported-by: Ingo Molnar <mingo@xxxxxxxxxx>
> Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
> Cc: David Ahern <dsahern@xxxxxxxxx>
> Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Link: http://lkml.kernel.org/r/20180423090823.32309-5-jolsa@xxxxxxxxxx
> Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> ---
> tools/perf/util/parse-events.y | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
> index 7afeb80cc39e..d14464c42714 100644
> --- a/tools/perf/util/parse-events.y
> +++ b/tools/perf/util/parse-events.y
> @@ -224,15 +224,15 @@ event_def: event_pmu |
> event_bpf_file
>
> event_pmu:
> -PE_NAME opt_event_config
> +PE_NAME '/' event_config '/'
These are not equivalent because opt_event_config allows '//'
but event_config cannot be an empty string.
> {
> struct list_head *list, *orig_terms, *terms;
>
> - if (parse_events_copy_term_list($2, &orig_terms))
> + if (parse_events_copy_term_list($3, &orig_terms))
> YYABORT;
>
> ALLOC_LIST(list);
> - if (parse_events_add_pmu(_parse_state, list, $1, $2, false)) {
> + if (parse_events_add_pmu(_parse_state, list, $1, $3, false)) {
> struct perf_pmu *pmu = NULL;
> int ok = 0;
> char *pattern;
> @@ -262,7 +262,7 @@ PE_NAME opt_event_config
> if (!ok)
> YYABORT;
> }
> - parse_events_terms__delete($2);
> + parse_events_terms__delete($3);
> parse_events_terms__delete(orig_terms);
> $$ = list;
> }
>