Re: [PATCH] perf stat: add rusage utime and stime events
From: Arnaldo Carvalho de Melo
Date: Tue Apr 05 2022 - 18:40:23 EST
Em Tue, Apr 05, 2022 at 07:40:28PM +0200, Florian Fischer escreveu:
> It bothered me that during benchmarking using perf stat (to collect
> for example CPU cache events) I could not simultaneously retrieve the
> times spend in user or kernel mode in a machine readable format.
>
> When running perf stat the output for humans contains the times
> reported by rusage and wait4.
>
> $ perf stat -e cache-misses:u -- true
>
> Performance counter stats for 'true':
>
> 4,206 cache-misses:u
>
> 0.001113619 seconds time elapsed
>
> 0.001175000 seconds user
> 0.000000000 seconds sys
>
> But using perf stats' machine-readable format does not provide this
> information.
>
> $ perf stat -x, -e cache-misses:u -- true
> 4282,,cache-misses:u,492859,100.00,,
>
> I found no way to retrieve this information using the available events
> while using machine-readable output.
>
> To solve this I added two new tool internal events 'rusage_user_time'
> and 'rusage_system_time' as well as their aliases 'ru_utime' and
> 'ru_stime', similarly to the already present 'duration_time' event.
>
> Both events use the already collected rusage information obtained by wait4.
>
> Examples presenting cache-misses and rusage information in both human and
> machine-readable form:
>
> $ ./perf stat -e duration_time,ru_utime,ru_stime,cache-misses -- grep -q -r duration_time .
>
> Performance counter stats for 'grep -q -r duration_time .':
>
> 67,422,542 ns duration_time:u
> 50,517 us ru_utime:u
> 16,839 us ru_stime:u
> 30,937 cache-misses:u
>
> 0.067422542 seconds time elapsed
>
> 0.050517000 seconds user
> 0.016839000 seconds sys
So, it looks useful indeed!
I suggest you break this patch into a series, to reduce its size and
help in reviewing.
For instance, you introduce evsel__tool_names, please do it in a
separate patch, initially only with the current "duration_time", then
you go on adding one new metric, then the other one.
More below.
> $ ./perf stat -x, -e duration_time,ru_utime,ru_stime,cache-misses -- grep -q -r duration_time .
> 72134524,ns,duration_time:u,72134524,100.00,,
> 65225,us,ru_utime:u,65225,100.00,,
> 6865,us,ru_stime:u,6865,100.00,,
> 38705,,cache-misses:u,71189328,100.00,,
>
> Signed-off-by: Florian Fischer <florian.fischer@muhq.space>
> ---
> tools/perf/builtin-stat.c | 41 ++++++++++++++++++++++++-------
> tools/perf/util/evsel.c | 19 +++++++++------
> tools/perf/util/evsel.h | 4 ++++
> tools/perf/util/parse-events.c | 44 +++++++++++++++++++++++++++++-----
> tools/perf/util/parse-events.l | 2 ++
> tools/perf/util/stat-shadow.c | 2 ++
> tools/perf/util/stat.h | 19 +++++++++++++++
> 7 files changed, 109 insertions(+), 22 deletions(-)
>
> diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
> index a96f106dc93a..c73afc8f6da5 100644
> --- a/tools/perf/builtin-stat.c
> +++ b/tools/perf/builtin-stat.c
> @@ -216,6 +216,7 @@ static struct perf_stat_config stat_config = {
> .run_count = 1,
> .metric_only_len = METRIC_ONLY_LEN,
> .walltime_nsecs_stats = &walltime_nsecs_stats,
> + .ru_stats = &ru_stats,
> .big_num = true,
> .ctl_fd = -1,
> .ctl_fd_ack = -1,
> @@ -341,15 +342,35 @@ static int evsel__write_stat_event(struct evsel *counter, int cpu_map_idx, u32 t
> static int read_single_counter(struct evsel *counter, int cpu_map_idx,
> int thread, struct timespec *rs)
> {
> - if (counter->tool_event == PERF_TOOL_DURATION_TIME) {
> - u64 val = rs->tv_nsec + rs->tv_sec*1000000000ULL;
> - struct perf_counts_values *count =
> - perf_counts(counter->counts, cpu_map_idx, thread);
> - count->ena = count->run = val;
> - count->val = val;
> - return 0;
> + switch(counter->tool_event) {
> + case PERF_TOOL_DURATION_TIME: {
> + u64 val = rs->tv_nsec + rs->tv_sec*1000000000ULL;
> + struct perf_counts_values *count =
> + perf_counts(counter->counts, cpu_map_idx, thread);
> + count->ena = count->run = val;
> + count->val = val;
> + return 0;
> + }
> + case PERF_TOOL_RU_UTIME:
> + case PERF_TOOL_RU_STIME: {
> + u64 val;
> + struct perf_counts_values *count =
> + perf_counts(counter->counts, cpu_map_idx, thread);
> + if (counter->tool_event == PERF_TOOL_RU_UTIME)
> + val = ru_stats.ru_utime_usec_stat.mean;
> + else
> + val = ru_stats.ru_stime_usec_stat.mean;
> + count->ena = count->run = val;
> + count->val = val;
> + return 0;
> + }
> + default:
> + case PERF_TOOL_NONE:
> + return evsel__read_counter(counter, cpu_map_idx, thread);
> + case PERF_TOOL_LAST:
> + /* this case should never be reached */
> + return 0;
> }
> - return evsel__read_counter(counter, cpu_map_idx, thread);
> }
>
> /*
> @@ -1010,8 +1031,10 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx)
> evlist__reset_prev_raw_counts(evsel_list);
> runtime_stat_reset(&stat_config);
> perf_stat__reset_shadow_per_stat(&rt_stat);
> - } else
> + } else {
> update_stats(&walltime_nsecs_stats, t1 - t0);
> + update_rusage_stats(&ru_stats, &stat_config.ru_data);
> + }
>
> /*
> * Closing a group leader splits the group, and as we only disable
> diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> index 2a1729e7aee4..26cf7e76698b 100644
> --- a/tools/perf/util/evsel.c
> +++ b/tools/perf/util/evsel.c
> @@ -597,6 +597,17 @@ static int evsel__sw_name(struct evsel *evsel, char *bf, size_t size)
> return r + evsel__add_modifiers(evsel, bf + r, size - r);
> }
>
> +const char *evsel__tool_names[PERF_TOOL_LAST] = {
> + "duration_time",
> + "rusage_user_time",
> + "rusage_system_time",
> +};
> +
> +static int evsel__tool_name(enum perf_tool_event ev, char *bf, size_t size)
> +{
> + return scnprintf(bf, size, "%s", evsel__tool_names[ev]);
> +}
> +
> static int __evsel__bp_name(char *bf, size_t size, u64 addr, u64 type)
> {
> int r;
> @@ -723,12 +734,6 @@ static int evsel__raw_name(struct evsel *evsel, char *bf, size_t size)
> return ret + evsel__add_modifiers(evsel, bf + ret, size - ret);
> }
>
> -static int evsel__tool_name(char *bf, size_t size)
> -{
> - int ret = scnprintf(bf, size, "duration_time");
> - return ret;
> -}
> -
> const char *evsel__name(struct evsel *evsel)
> {
> char bf[128];
> @@ -754,7 +759,7 @@ const char *evsel__name(struct evsel *evsel)
>
> case PERF_TYPE_SOFTWARE:
> if (evsel->tool_event)
> - evsel__tool_name(bf, sizeof(bf));
> + evsel__tool_name(evsel->tool_event, bf, sizeof(bf));
> else
> evsel__sw_name(evsel, bf, sizeof(bf));
> break;
> diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
> index 041b42d33bf5..2adb97383952 100644
> --- a/tools/perf/util/evsel.h
> +++ b/tools/perf/util/evsel.h
> @@ -30,6 +30,9 @@ typedef int (evsel__sb_cb_t)(union perf_event *event, void *data);
> enum perf_tool_event {
> PERF_TOOL_NONE = 0,
> PERF_TOOL_DURATION_TIME = 1,
> + PERF_TOOL_RU_UTIME = 2,
> + PERF_TOOL_RU_STIME = 3,
> + PERF_TOOL_LAST
> };
>
> /** struct evsel - event selector
> @@ -258,6 +261,7 @@ extern const char *evsel__hw_cache_op[PERF_COUNT_HW_CACHE_OP_MAX][EVSEL__MAX_ALI
> extern const char *evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX][EVSEL__MAX_ALIASES];
> extern const char *evsel__hw_names[PERF_COUNT_HW_MAX];
> extern const char *evsel__sw_names[PERF_COUNT_SW_MAX];
> +extern const char *evsel__tool_names[PERF_TOOL_LAST];
> extern char *evsel__bpf_counter_events;
> bool evsel__match_bpf_counter_events(const char *name);
>
> diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
> index 24997925ae00..13db69b71187 100644
> --- a/tools/perf/util/parse-events.c
> +++ b/tools/perf/util/parse-events.c
> @@ -154,6 +154,21 @@ struct event_symbol event_symbols_sw[PERF_COUNT_SW_MAX] = {
> },
> };
>
> +struct event_symbol event_symbols_tool[PERF_TOOL_LAST] = {
> + [PERF_TOOL_DURATION_TIME] = {
> + .symbol = "duration_time",
> + .alias = "",
> + },
> + [PERF_TOOL_RU_UTIME] = {
> + .symbol = "rusage_user_time",
> + .alias = "ru_utime",
> + },
> + [PERF_TOOL_RU_STIME] = {
> + .symbol = "rusage_system_time",
> + .alias = "ru_stime",
> + },
> +};
> +
> #define __PERF_EVENT_FIELD(config, name) \
> ((config & PERF_EVENT_##name##_MASK) >> PERF_EVENT_##name##_SHIFT)
>
> @@ -406,6 +421,10 @@ static int add_event_tool(struct list_head *list, int *idx,
> free((char *)evsel->unit);
> evsel->unit = strdup("ns");
> }
> + else if (tool_event == PERF_TOOL_RU_UTIME || tool_event == PERF_TOOL_RU_STIME) {
> + free((char *)evsel->unit);
> + evsel->unit = strdup("us");
> + }
> return 0;
> }
>
> @@ -3055,21 +3074,34 @@ int print_hwcache_events(const char *event_glob, bool name_only)
> return evt_num;
> }
>
> -static void print_tool_event(const char *name, const char *event_glob,
> +static void print_tool_event(const struct event_symbol *syms, const char *event_glob,
> bool name_only)
> {
> - if (event_glob && !strglobmatch(name, event_glob))
> + if (syms->symbol == NULL)
> + return;
> +
> + if (event_glob && !(strglobmatch(syms->symbol, event_glob) ||
> + (syms->alias && strglobmatch(syms->alias, event_glob))))
> return;
> +
> if (name_only)
> - printf("%s ", name);
> - else
> + printf("%s ", syms->symbol);
> + else {
> + char name[MAX_NAME_LEN];
> + if (syms->alias)
> + snprintf(name, MAX_NAME_LEN, "%s OR %s", syms->symbol, syms->alias);
> + else
> + strlcpy(name, syms->symbol, MAX_NAME_LEN);
> printf(" %-50s [%s]\n", name, "Tool event");
> -
> + }
> }
>
> void print_tool_events(const char *event_glob, bool name_only)
> {
> - print_tool_event("duration_time", event_glob, name_only);
> + // Start at 1 because the first enum entry symbols no tool event
> + for (int i = 0; i < PERF_TOOL_LAST; ++i) {
> + print_tool_event(event_symbols_tool + i, event_glob, name_only);
> + }
> if (pager_in_use())
> printf("\n");
> }
> diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
> index 5b6e4b5249cf..3c7227b8035c 100644
> --- a/tools/perf/util/parse-events.l
> +++ b/tools/perf/util/parse-events.l
> @@ -353,6 +353,8 @@ alignment-faults { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_AL
> emulation-faults { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_EMULATION_FAULTS); }
> dummy { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_DUMMY); }
> duration_time { return tool(yyscanner, PERF_TOOL_DURATION_TIME); }
> +rusage_user_time|ru_utime { return tool(yyscanner, PERF_TOOL_RU_UTIME); }
> +rusage_system_time|ru_stime { return tool(yyscanner, PERF_TOOL_RU_STIME); }
> bpf-output { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_BPF_OUTPUT); }
> cgroup-switches { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_CGROUP_SWITCHES); }
>
> diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
> index 10af7804e482..ea4c35e4f1da 100644
> --- a/tools/perf/util/stat-shadow.c
> +++ b/tools/perf/util/stat-shadow.c
> @@ -26,6 +26,7 @@
>
> struct runtime_stat rt_stat;
> struct stats walltime_nsecs_stats;
> +struct rusage_stats ru_stats;
>
> struct saved_value {
> struct rb_node rb_node;
> @@ -199,6 +200,7 @@ void perf_stat__reset_shadow_stats(void)
> {
> reset_stat(&rt_stat);
> memset(&walltime_nsecs_stats, 0, sizeof(walltime_nsecs_stats));
> + memset(&ru_stats, 0, sizeof(ru_stats));
> }
>
> void perf_stat__reset_shadow_per_stat(struct runtime_stat *st)
> diff --git a/tools/perf/util/stat.h b/tools/perf/util/stat.h
> index 335d19cc3063..b14a45d8af63 100644
> --- a/tools/perf/util/stat.h
> +++ b/tools/perf/util/stat.h
> @@ -108,6 +108,11 @@ struct runtime_stat {
> struct rblist value_list;
> };
>
> +struct rusage_stats {
> + struct stats ru_utime_usec_stat;
> + struct stats ru_stime_usec_stat;
> +};
> +
This could be added in a separate patch that introduces this struct, the
global variable and the init/update rusage_stats.
Then you add one of the new metrics, then the other one.
Doing it in a granular way helps with reviewing and also when using 'git
bisect' to find problems.
Thanks for working on this!
- Arnaldo
> typedef struct aggr_cpu_id (*aggr_get_id_t)(struct perf_stat_config *config, struct perf_cpu cpu);
>
> struct perf_stat_config {
> @@ -148,6 +153,7 @@ struct perf_stat_config {
> const char *csv_sep;
> struct stats *walltime_nsecs_stats;
> struct rusage ru_data;
> + struct rusage_stats *ru_stats;
> struct cpu_aggr_map *aggr_map;
> aggr_get_id_t aggr_get_id;
> struct cpu_aggr_map *cpus_aggr_map;
> @@ -177,6 +183,18 @@ static inline void init_stats(struct stats *stats)
> stats->max = 0;
> }
>
> +static inline void init_rusage_stats(struct rusage_stats *ru_stats) {
> + init_stats(&ru_stats->ru_utime_usec_stat);
> + init_stats(&ru_stats->ru_stime_usec_stat);
> +}
> +
> +static inline void update_rusage_stats(struct rusage_stats *ru_stats, struct rusage* rusage) {
> + update_stats(&ru_stats->ru_utime_usec_stat,
> + (rusage->ru_utime.tv_usec + rusage->ru_utime.tv_sec * 1000000ULL));
> + update_stats(&ru_stats->ru_stime_usec_stat,
> + (rusage->ru_stime.tv_usec + rusage->ru_stime.tv_sec * 1000000ULL));
> +}
> +
> struct evsel;
> struct evlist;
>
> @@ -196,6 +214,7 @@ bool __perf_stat_evsel__is(struct evsel *evsel, enum perf_stat_evsel_id id);
>
> extern struct runtime_stat rt_stat;
> extern struct stats walltime_nsecs_stats;
> +extern struct rusage_stats ru_stats;
>
> typedef void (*print_metric_t)(struct perf_stat_config *config,
> void *ctx, const char *color, const char *unit,
> --
> 2.35.1
--
- Arnaldo