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

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Message-ID: <YHBa15BWne4zgv/A@krava>
Date:   Fri, 9 Apr 2021 15:47:03 +0200
From:   Jiri Olsa <jolsa@...hat.com>
To:     Jin Yao <yao.jin@...ux.intel.com>
Cc:     acme@...nel.org, jolsa@...nel.org, peterz@...radead.org,
        mingo@...hat.com, alexander.shishkin@...ux.intel.com,
        Linux-kernel@...r.kernel.org, ak@...ux.intel.com,
        kan.liang@...el.com, yao.jin@...el.com
Subject: Re: [PATCH v3 12/27] perf parse-events: Support no alias assigned
 event inside hybrid PMU

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?

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

> +	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 (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