Commit 430daf2d authored by Andi Kleen's avatar Andi Kleen Committed by Arnaldo Carvalho de Melo
Browse files

perf stat: Collapse identically named events 



The uncore PMU has a lot of duplicated PMUs for different subsystems.
When expanding an uncore alias we usually end up with a large
number of identically named aliases, which makes perf stat
output difficult to read.

Automatically sum them up in perf stat, unless --no-merge is specified.

This can be default because only the uncores generally have duplicated
aliases. Other PMUs have unique names.

Before:

  % perf stat --no-merge -a -e unc_c_llc_lookup.any sleep 1

  Performance counter stats for 'system wide':

           694,976 Bytes unc_c_llc_lookup.any
           706,304 Bytes unc_c_llc_lookup.any
           956,608 Bytes unc_c_llc_lookup.any
           782,720 Bytes unc_c_llc_lookup.any
           605,696 Bytes unc_c_llc_lookup.any
           442,816 Bytes unc_c_llc_lookup.any
           659,328 Bytes unc_c_llc_lookup.any
           509,312 Bytes unc_c_llc_lookup.any
           263,936 Bytes unc_c_llc_lookup.any
           592,448 Bytes unc_c_llc_lookup.any
           672,448 Bytes unc_c_llc_lookup.any
           608,640 Bytes unc_c_llc_lookup.any
           641,024 Bytes unc_c_llc_lookup.any
           856,896 Bytes unc_c_llc_lookup.any
           808,832 Bytes unc_c_llc_lookup.any
           684,864 Bytes unc_c_llc_lookup.any
           710,464 Bytes unc_c_llc_lookup.any
           538,304 Bytes unc_c_llc_lookup.any

       1.002577660 seconds time elapsed

After:

  % perf stat -a -e unc_c_llc_lookup.any sleep 1

  Performance counter stats for 'system wide':

         2,685,120 Bytes unc_c_llc_lookup.any

       1.002648032 seconds time elapsed

v2: Split collect_aliases. Rename alias flag.
v3: Make sure unsupported/not counted is always printed.
v4: Factor out callback change into separate patch.
v5: Move check for bad results here
    Move merged check into collect_data

Signed-off-by: default avatarAndi Kleen <ak@linux.intel.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Link: http://lkml.kernel.org/r/20170320201711.14142-3-andi@firstfloor.org


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent fbe51fba

tools/perf/Documentation/perf-stat.txt

+3 −0
Original line number Diff line number Diff line
@@ -236,6 +236,9 @@ To interpret the results it is usually needed to know on which 
CPUs the workload runs on. If needed the CPUs can be forced using

taskset.



--no-merge::

Do not merge results from same PMUs.



EXAMPLES

--------

tools/perf/builtin-stat.c

+34 −4
Original line number Diff line number Diff line
@@ -140,6 +140,7 @@ static unsigned int unit_width = 4; /* strlen("unit") */ 
static bool			forever				= false;

static bool			metric_only			= false;

static bool			force_metric_only		= false;

static bool			no_merge			= false;

static struct timespec		ref_time;

static struct cpu_map		*aggr_map;

static aggr_get_id_t		aggr_get_id;
@@ -1182,12 +1183,37 @@ static void aggr_update_shadow(void) 
	}

}



static void collect_data(struct perf_evsel *counter,

static void collect_all_aliases(struct perf_evsel *counter,

			    void (*cb)(struct perf_evsel *counter, void *data,

				       bool first),

			    void *data)

{

	struct perf_evsel *alias;



	alias = list_prepare_entry(counter, &(evsel_list->entries), node);

	list_for_each_entry_continue (alias, &evsel_list->entries, node) {

		if (strcmp(perf_evsel__name(alias), perf_evsel__name(counter)) ||

		    alias->scale != counter->scale ||

		    alias->cgrp != counter->cgrp ||

		    strcmp(alias->unit, counter->unit) ||

		    nsec_counter(alias) != nsec_counter(counter))

			break;

		alias->merged_stat = true;

		cb(alias, data, false);

	}

}



static bool collect_data(struct perf_evsel *counter,

			    void (*cb)(struct perf_evsel *counter, void *data,

				       bool first),

			    void *data)

{

	if (counter->merged_stat)

		return false;

	cb(counter, data, true);

	if (!no_merge)

		collect_all_aliases(counter, cb, data);

	return true;

}



struct aggr_data {
@@ -1245,7 +1271,8 @@ static void print_aggr(char *prefix) 
		evlist__for_each_entry(evsel_list, counter) {

			ad.val = ad.ena = ad.run = 0;

			ad.nr = 0;

			collect_data(counter, aggr_cb, &ad);

			if (!collect_data(counter, aggr_cb, &ad))

				continue;

			nr = ad.nr;

			ena = ad.ena;

			run = ad.run;
@@ -1318,7 +1345,8 @@ static void print_counter_aggr(struct perf_evsel *counter, char *prefix) 
	double uval;

	struct caggr_data cd = { .avg = 0.0 };



	collect_data(counter, counter_aggr_cb, &cd);

	if (!collect_data(counter, counter_aggr_cb, &cd))

		return;



	if (prefix && !metric_only)

		fprintf(output, "%s", prefix);
@@ -1353,7 +1381,8 @@ static void print_counter(struct perf_evsel *counter, char *prefix) 
	for (cpu = 0; cpu < perf_evsel__nr_cpus(counter); cpu++) {

		struct aggr_data ad = { .cpu = cpu };



		collect_data(counter, counter_cb, &ad);

		if (!collect_data(counter, counter_cb, &ad))

			return;

		val = ad.val;

		ena = ad.ena;

		run = ad.run;
@@ -1701,6 +1730,7 @@ static const struct option stat_options[] = { 
		    "list of cpus to monitor in system-wide"),

	OPT_SET_UINT('A', "no-aggr", &stat_config.aggr_mode,

		    "disable CPU count aggregation", AGGR_NONE),

	OPT_BOOLEAN(0, "no-merge", &no_merge, "Do not merge identical named events"),

	OPT_STRING('x', "field-separator", &csv_sep, "separator",

		   "print counts with custom separator"),

	OPT_CALLBACK('G', "cgroup", &evsel_list, "name",

tools/perf/util/evsel.h

+1 −0
Original line number Diff line number Diff line
@@ -131,6 +131,7 @@ struct perf_evsel { 
	bool			cmdline_group_boundary;

	struct list_head	config_terms;

	int			bpf_fd;

	bool			merged_stat;

};



union u64_swap {

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