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

Jin, Yao
2021-04-22T01:44:51Z

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
>>
>