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perf stat: Fix counting when initial delay configured

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When creating counters with initial delay configured, the enable_on_exec
field is not set. So we need to enable the counters later. The problem
is, when a workload is specified the target__none() is true. So we also
need to check stat_config.initial_delay.

In this change, we add a new field 'initial_delay' for struct target
which could be shared by other subcommands. And define
target__enable_on_exec() which returns whether enable_on_exec should be
set on normal cases.

Before this fix the event is not counted:

  $ ./perf stat -e instructions -D 100 sleep 2
  Events disabled
  Events enabled

   Performance counter stats for 'sleep 2':

       <not counted>      instructions

         1.901661124 seconds time elapsed

         0.001602000 seconds user
         0.000000000 seconds sys

After fix it works:

  $ ./perf stat -e instructions -D 100 sleep 2
  Events disabled
  Events enabled

   Performance counter stats for 'sleep 2':

             404,214      instructions

         1.901743475 seconds time elapsed

         0.001617000 seconds user
         0.000000000 seconds sys

Fixes: c587e77e10 ("perf stat: Do not delay the workload with --delay")
Signed-off-by: Changbin Du <changbin.du@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hui Wang <hw.huiwang@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230302031146.2801588-2-changbin.du@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Changbin Du 2023-03-02 11:11:44 +08:00 committed by Arnaldo Carvalho de Melo
parent a98c0710b4
commit 25f69c69bc
4 changed files with 18 additions and 16 deletions
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15
tools/perf/builtin-stat.c
View File

@ -539,12 +539,7 @@ static int enable_counters(void)
return err;
}
/*
* We need to enable counters only if:
* - we don't have tracee (attaching to task or cpu)
* - we have initial delay configured
*/
if (!target__none(&target)) {
if (!target__enable_on_exec(&target)) {
if (!all_counters_use_bpf)
evlist__enable(evsel_list);
}
@ -914,7 +909,7 @@ try_again_reset:
return err;
}
if (stat_config.initial_delay) {
if (target.initial_delay) {
pr_info(EVLIST_DISABLED_MSG);
} else {
err = enable_counters();
@ -926,8 +921,8 @@ try_again_reset:
if (forks)
evlist__start_workload(evsel_list);
if (stat_config.initial_delay > 0) {
usleep(stat_config.initial_delay * USEC_PER_MSEC);
if (target.initial_delay > 0) {
usleep(target.initial_delay * USEC_PER_MSEC);
err = enable_counters();
if (err)
return -1;
@ -1248,7 +1243,7 @@ static struct option stat_options[] = {
"aggregate counts per thread", AGGR_THREAD),
OPT_SET_UINT(0, "per-node", &stat_config.aggr_mode,
"aggregate counts per numa node", AGGR_NODE),
OPT_INTEGER('D', "delay", &stat_config.initial_delay,
OPT_INTEGER('D', "delay", &target.initial_delay,
"ms to wait before starting measurement after program start (-1: start with events disabled)"),
OPT_CALLBACK_NOOPT(0, "metric-only", &stat_config.metric_only, NULL,
"Only print computed metrics. No raw values", enable_metric_only),

6
tools/perf/util/stat.c
View File

@ -842,11 +842,7 @@ int create_perf_stat_counter(struct evsel *evsel,
if (evsel__is_group_leader(evsel)) {
attr->disabled = 1;
/*
* In case of initial_delay we enable tracee
* events manually.
*/
if (target__none(target) && !config->initial_delay)
if (target__enable_on_exec(target))
attr->enable_on_exec = 1;
}

1
tools/perf/util/stat.h
View File

@ -166,7 +166,6 @@ struct perf_stat_config {
FILE *output;
unsigned int interval;
unsigned int timeout;
int initial_delay;
unsigned int unit_width;
unsigned int metric_only_len;
int times;

12
tools/perf/util/target.h
View File

@ -18,6 +18,7 @@ struct target {
bool per_thread;
bool use_bpf;
bool hybrid;
int initial_delay;
const char *attr_map;
};
@ -72,6 +73,17 @@ static inline bool target__none(struct target *target)
return !target__has_task(target) && !target__has_cpu(target);
}
static inline bool target__enable_on_exec(struct target *target)
{
/*
* Normally enable_on_exec should be set if:
* 1) The tracee process is forked (not attaching to existed task or cpu).
* 2) And initial_delay is not configured.
* Otherwise, we enable tracee events manually.
*/
return target__none(target) && !target->initial_delay;
}
static inline bool target__has_per_thread(struct target *target)
{
return target->system_wide && target->per_thread;