Re: [PATCH v3 12/27] perf parse-events: Support no alias assigned event inside hybrid PMU

Jin, Yao
2021-04-12T02:53:38Z

Hi Jiri,

On 4/9/2021 9:47 PM, Jiri Olsa wrote:
> On Mon, Mar 29, 2021 at 03:00:31PM +0800, Jin Yao wrote:
>
> SNIP
>
>> + struct parse_events_state *parse_state)
>> {
>> struct perf_event_attr attr;
>> LIST_HEAD(config_terms);
>> @@ -521,7 +526,7 @@ int parse_events_add_cache(struct list_head *list, int *idx,
>>
>> i = parse_events__add_cache_hybrid(list, idx, &attr,
>> config_name ? : name, &config_terms,
>> - &hybrid);
>> + &hybrid, parse_state);
>> if (hybrid)
>> return i;
>>
>> @@ -1481,7 +1486,7 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
>> struct perf_pmu *pmu;
>> struct evsel *evsel;
>> struct parse_events_error *err = parse_state->error;
>> - bool use_uncore_alias;
>> + bool use_uncore_alias, found = false;
>> LIST_HEAD(config_terms);
>>
>> if (verbose > 1) {
>> @@ -1530,8 +1535,28 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
>> }
>> }
>>
>> - if (!parse_state->fake_pmu && perf_pmu__check_alias(pmu, head_config, &info))
>> + if (!parse_state->fake_pmu &&
>> + perf_pmu__check_alias(pmu, head_config, &info, &found)) {
>> return -EINVAL;
>> + }
>> +
>
> ok, let's not polute surronding functions and make strict check
> on what we want in here.. we are after following events:
>
> cpu_xxx/L1-dcache/
> cpu_xxx/l1-d|/
> ...
> right?
>

Yes, we only focus on the cache events now.

> so we are after events with single term in head_config that has name in:
>
> L1-dcache|l1-d|l1d|L1-data |
> L1-icache|l1-i|l1i|L1-instruction |
> LLC|L2 |
> dTLB|d-tlb|Data-TLB |
> iTLB|i-tlb|Instruction-TLB |
> branch|branches|bpu|btb|bpc |
> node
>
> I think that with such direct check the code will be more straight
> forward, also let's move it to parse-events-hybrid
>

Do you suggest we just use string comparison for doing the direct check?

e.g.

if (strstr(term->config, "L1-dcache"))
...

Of course, we can define a string array first and use a loop for string comparison.

>> + if (!parse_state->fake_pmu && head_config && !found &&
>> + perf_pmu__is_hybrid(name)) {
>> + struct parse_events_term *term;
>> + int ret;
>> +
>> + list_for_each_entry(term, head_config, list) {
>> + if (!term->config)
>> + continue;
>> +
>> + ret = parse_events__with_hybrid_pmu(parse_state,
>> + term->config,
>> + name, &found,
>> + list);
>
> do we need to call the parsing again? could we just call
> parse_events__add_cache_hybrid?
>
> jirka
>
>

If we do the direct check for cache events, I think we don't need the parsing again.

As I mentioned above, we need to define a string array and compare with term->config one by one.

I'm OK for this solution. :)

Thanks
Jin Yao

>> + if (found)
>> + return ret;
>> + }
>> + }
>>
>> if (verbose > 1) {
>> fprintf(stderr, "After aliases, add event pmu '%s' with '",
>> @@ -1605,6 +1630,15 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
>> struct perf_pmu *pmu = NULL;
>> int ok = 0;
>>
>
> SNIP
>