Re: [PATCH v4 12/25] perf parse-events: Support event inside hybrid pmu

[Jin, Yao]

Hi Jiri,

On 4/22/2021 2:29 AM, Jiri Olsa wrote:
> On Fri, Apr 16, 2021 at 10:05:04PM +0800, Jin Yao wrote:
>
> SNIP
>
> > ---
> > v4:
> >   - New in v4.
> >
> >   tools/perf/util/parse-events.c | 55 ++++++++++++++++++++++++++++++++++
> >   1 file changed, 55 insertions(+)
> >
> > diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
> > index f69475a158bb..bd3fd722b4ac 100644
> > --- a/tools/perf/util/parse-events.c
> > +++ b/tools/perf/util/parse-events.c
> > @@ -38,6 +38,7 @@
> >   #include "util/event.h"
> >   #include "util/pfm.h"
> >   #include "util/parse-events-hybrid.h"
> > +#include "util/pmu-hybrid.h"
> >   #include "perf.h"
> >   
> >   #define MAX_NAME_LEN 100
> > @@ -48,6 +49,9 @@ extern int parse_events_debug;
> >   int parse_events_parse(void *parse_state, void *scanner);
> >   static int get_config_terms(struct list_head *head_config,
> >   			    struct list_head *head_terms __maybe_unused);
> > +static int parse_events__with_hybrid_pmu(struct parse_events_state *parse_state,
> > +					 const char *str, char *pmu_name,
> > +					 struct list_head *list, bool *parsed);
> >   
> >   static struct perf_pmu_event_symbol *perf_pmu_events_list;
> >   /*
> > @@ -1567,6 +1571,27 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
> >   	if (pmu->default_config && get_config_chgs(pmu, head_config, &config_terms))
> >   		return -ENOMEM;
> >   
> > +	if (!parse_state->fake_pmu && head_config &&
> > +	    perf_pmu__is_hybrid(name)) {
> > +		struct parse_events_term *term;
> > +		bool parsed;
> > +		int ret;
> > +
> > +		term = list_first_entry(head_config, struct parse_events_term,
> > +					list);
>
> you need to test that there's something in the head_config first,
> and I thought you wanted to check that there's just 1 term, right?
> (you could check the next pointer == head_config)

Yes, agree, we need to check the head_config has only one term first. Otherwise we don't need to do 
the second parsing.

> also please move this to separated function

OK.

> > +		if (term && term->config && strcmp(term->config, "event")) {
> > +			ret = parse_events__with_hybrid_pmu(parse_state,
> > +							    term->config, name,
> > +							    list, &parsed);
> > +			/*
> > +			 * If the string inside the pmu can't be parsed,
> > +			 * don't return, try next steps.
> > +			 */
> > +			if (parsed)
> > +				return ret;
>
> so if the function fails we ignore the return value,
> because parsed is set only for ret == 0, so I think we
> don't need 'parsed' param and we could make parse_events__with_hybrid_pmu
> return 0 when we found some event and let it go through otherwise

That makes sense. We let the parse_events__with_hybrid_pmu just returns 0 when we can find some 
events in second parsing. If there are no events parsed or something error occurs, 
parse_events__with_hybrid_pmu returns error value then we can go through other cases.

> > +		}
> > +	}
> > +
> >   	if (!parse_state->fake_pmu && perf_pmu__config(pmu, &attr, head_config, parse_state->error)) {
> >   		struct evsel_config_term *pos, *tmp;
> >   
> > @@ -1585,6 +1610,9 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
> >   	if (!evsel)
> >   		return -ENOMEM;
> >   
> > +	if (evsel->name)
> > +		evsel->use_config_name = true;
>
> should this go to:
>   perf stat: Uniquify hybrid event name
> ?

OK, I will move this to patch "perf stat: Uniquify hybrid event name".

> thanks,
> jirka

Thanks
Jin Yao

> > +
> >   	evsel->pmu_name = name ? strdup(name) : NULL;
> >   	evsel->use_uncore_alias = use_uncore_alias;
> >   	evsel->percore = config_term_percore(&evsel->config_terms);
> > @@ -2180,6 +2208,33 @@ int parse_events_terms(struct list_head *terms, const char *str)
> >   	return ret;
> >   }
> >   
> > +static int parse_events__with_hybrid_pmu(struct parse_events_state *parse_state,
> > +					 const char *str, char *pmu_name,
> > +					 struct list_head *list, bool *parsed)
> > +{
> > +	struct parse_events_state ps = {
> > +		.list            = LIST_HEAD_INIT(ps.list),
> > +		.stoken          = PE_START_EVENTS,
> > +		.hybrid_pmu_name = pmu_name,
> > +		.idx             = parse_state->idx,
> > +	};
> > +	int ret;
> > +
> > +	*parsed = false;
> > +	ret = parse_events__scanner(str, &ps);
> > +	perf_pmu__parse_cleanup();
> > +
> > +	if (!ret) {
> > +		if (!list_empty(&ps.list)) {
> > +			*parsed = true;
> > +			list_splice(&ps.list, list);
> > +			parse_state->idx = ps.idx;
> > +		}
> > +	}
> > +
> > +	return ret;
> > +}
> > +
> >   int __parse_events(struct evlist *evlist, const char *str,
> >   		   struct parse_events_error *err, struct perf_pmu *fake_pmu)
> >   {
> > --
> > 2.17.1