Commit d8d8a0b3 authored by Ian Rogers's avatar Ian Rogers Committed by Namhyung Kim
Browse files

perf tool_pmu: More accurately set the cpus for tool events 



The user and system time events can record on different CPUs, but for
all other events a single CPU map of just CPU 0 makes sense. In
parse-events detect a tool PMU and then pass the perf_event_attr so
that the tool_pmu can return CPUs specific for the event. This avoids
a CPU map of all online CPUs being used for events like
duration_time. Avoiding this avoids the evlist CPUs containing CPUs
for which duration_time just gives 0. Minimizing the evlist CPUs can
remove unnecessary sched_setaffinity syscalls that delay metric
calculations.

Signed-off-by: default avatarIan Rogers <irogers@google.com>
Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
parent d702c0f4

tools/perf/util/parse-events.c

+7 −2
Original line number Diff line number Diff line
@@ -30,6 +30,7 @@ 
#include "util/event.h"

#include "util/bpf-filter.h"

#include "util/stat.h"

#include "util/tool_pmu.h"

#include "util/util.h"

#include "tracepoint.h"

#include <api/fs/tracing_path.h>
@@ -227,8 +228,12 @@ __add_event(struct list_head *list, int *idx, 
	if (pmu) {

		is_pmu_core = pmu->is_core;

		pmu_cpus = perf_cpu_map__get(pmu->cpus);

		if (perf_cpu_map__is_empty(pmu_cpus))

		if (perf_cpu_map__is_empty(pmu_cpus)) {

			if (perf_pmu__is_tool(pmu))

				pmu_cpus = tool_pmu__cpus(attr);

			else

				pmu_cpus = cpu_map__online();

		}

	} else {

		is_pmu_core = (attr->type == PERF_TYPE_HARDWARE ||

			       attr->type == PERF_TYPE_HW_CACHE);

tools/perf/util/tool_pmu.c

+19 −0
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ 
#include "cgroup.h"

#include "counts.h"

#include "cputopo.h"

#include "debug.h"

#include "evsel.h"

#include "pmu.h"

#include "print-events.h"
@@ -13,6 +14,7 @@ 
#include <api/fs/fs.h>

#include <api/io.h>

#include <internal/threadmap.h>

#include <perf/cpumap.h>

#include <perf/threadmap.h>

#include <fcntl.h>

#include <strings.h>
@@ -109,6 +111,23 @@ const char *evsel__tool_pmu_event_name(const struct evsel *evsel) 
	return tool_pmu__event_to_str(evsel->core.attr.config);

}



struct perf_cpu_map *tool_pmu__cpus(struct perf_event_attr *attr)

{

	static struct perf_cpu_map *cpu0_map;

	enum tool_pmu_event event = (enum tool_pmu_event)attr->config;



	if (event <= TOOL_PMU__EVENT_NONE || event >= TOOL_PMU__EVENT_MAX) {

		pr_err("Invalid tool PMU event config %llx\n", attr->config);

		return NULL;

	}

	if (event == TOOL_PMU__EVENT_USER_TIME || event == TOOL_PMU__EVENT_SYSTEM_TIME)

		return cpu_map__online();



	if (!cpu0_map)

		cpu0_map = perf_cpu_map__new_int(0);

	return perf_cpu_map__get(cpu0_map);

}



static bool read_until_char(struct io *io, char e)

{

	int c;

tools/perf/util/tool_pmu.h

+1 −0
Original line number Diff line number Diff line
@@ -46,6 +46,7 @@ bool tool_pmu__read_event(enum tool_pmu_event ev, 
u64 tool_pmu__cpu_slots_per_cycle(void);



bool perf_pmu__is_tool(const struct perf_pmu *pmu);

struct perf_cpu_map *tool_pmu__cpus(struct perf_event_attr *attr);



bool evsel__is_tool(const struct evsel *evsel);

enum tool_pmu_event evsel__tool_event(const struct evsel *evsel);