Re: [PATCH 05/14] perf tools: Add parse_events_fake interface

Jiri Olsa
2020-06-01T09:09:03Z

On Mon, Jun 01, 2020 at 12:28:31AM -0700, Ian Rogers wrote:
> On Sun, May 24, 2020 at 3:42 PM Jiri Olsa <jolsa@kernel.org> wrote:
> >
> > Adding parse_events_fake interface to parse events
> > and use fake pmu event in case pmu event is parsed.
> >
> > This way it's possible to parse events from PMUs
> > which are not present in the system. It's available
> > only for testing purposes coming in following
> > changes.
> >
> > Signed-off-by: Jiri Olsa <jolsa@kernel.org>
>
> Acked-by: Ian Rogers <irogers@google.com>
>
> Alternatively fake_pmu could be an argument to parse_events.

yea I checked that and I was surprised how many parse_events calls
we have in perf, so I went this way.. but I haven't really tried it,
so it might look actually etter despite the many places we need to change,
I'll try

thanks,
jirka

>
> Thanks,
> Ian
>
> > ---
> > tools/perf/util/parse-events.c | 48 +++++++++++++++++++++++++---------
> > tools/perf/util/parse-events.h | 2 ++
> > 2 files changed, 37 insertions(+), 13 deletions(-)
> >
> > diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
> > index 8304f9b6e6be..89239695a728 100644
> > --- a/tools/perf/util/parse-events.c
> > +++ b/tools/perf/util/parse-events.c
> > @@ -2082,22 +2082,15 @@ int parse_events_terms(struct list_head *terms, const char *str)
> > return ret;
> > }
> >
> > -int parse_events(struct evlist *evlist, const char *str,
> > - struct parse_events_error *err)
> > +static int parse_events_state(struct parse_events_state *parse_state,
> > + struct evlist *evlist, const char *str)
> > {
> > - struct parse_events_state parse_state = {
> > - .list = LIST_HEAD_INIT(parse_state.list),
> > - .idx = evlist->core.nr_entries,
> > - .error = err,
> > - .evlist = evlist,
> > - .stoken = PE_START_EVENTS,
> > - };
> > int ret;
> >
> > - ret = parse_events__scanner(str, &parse_state);
> > + ret = parse_events__scanner(str, parse_state);
> > perf_pmu__parse_cleanup();
> >
> > - if (!ret && list_empty(&parse_state.list)) {
> > + if (!ret && list_empty(&parse_state->list)) {
> > WARN_ONCE(true, "WARNING: event parser found nothing\n");
> > return -1;
> > }
> > @@ -2105,12 +2098,12 @@ int parse_events(struct evlist *evlist, const char *str,
> > /*
> > * Add list to the evlist even with errors to allow callers to clean up.
> > */
> > - perf_evlist__splice_list_tail(evlist, &parse_state.list);
> > + perf_evlist__splice_list_tail(evlist, &parse_state->list);
> >
> > if (!ret) {
> > struct evsel *last;
> >
> > - evlist->nr_groups += parse_state.nr_groups;
> > + evlist->nr_groups += parse_state->nr_groups;
> > last = evlist__last(evlist);
> > last->cmdline_group_boundary = true;
> >
> > @@ -2125,6 +2118,35 @@ int parse_events(struct evlist *evlist, const char *str,
> > return ret;
> > }
> >
> > +int parse_events(struct evlist *evlist, const char *str,
> > + struct parse_events_error *err)
> > +{
> > + struct parse_events_state parse_state = {
> > + .list = LIST_HEAD_INIT(parse_state.list),
> > + .idx = evlist->core.nr_entries,
> > + .error = err,
> > + .evlist = evlist,
> > + .stoken = PE_START_EVENTS,
> > + };
> > +
> > + return parse_events_state(&parse_state, evlist, str);
> > +}
> > +
> > +int parse_events_fake(struct evlist *evlist, const char *str,
> > + struct parse_events_error *err)
> > +{
> > + struct parse_events_state parse_state = {
> > + .list = LIST_HEAD_INIT(parse_state.list),
> > + .idx = evlist->core.nr_entries,
> > + .error = err,
> > + .evlist = evlist,
> > + .stoken = PE_START_EVENTS,
> > + .fake_pmu = true,
> > + };
> > +
> > + return parse_events_state(&parse_state, evlist, str);
> > +}
> > +
> > #define MAX_WIDTH 1000
> > static int get_term_width(void)
> > {
> > diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
> > index 963b0ea6c448..4a23b6cd9924 100644
> > --- a/tools/perf/util/parse-events.h
> > +++ b/tools/perf/util/parse-events.h
> > @@ -34,6 +34,8 @@ int parse_events_option(const struct option *opt, const char *str, int unset);
> > int parse_events_option_new_evlist(const struct option *opt, const char *str, int unset);
> > int parse_events(struct evlist *evlist, const char *str,
> > struct parse_events_error *error);
> > +int parse_events_fake(struct evlist *evlist, const char *str,
> > + struct parse_events_error *error);
> > int parse_events_terms(struct list_head *terms, const char *str);
> > int parse_filter(const struct option *opt, const char *str, int unset);
> > int exclude_perf(const struct option *opt, const char *arg, int unset);
> > --
> > 2.25.4
> >
>