[v2,1/3] perf stat: fix counting when initial delay configured
Commit Message
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: c587e77e100f ("perf stat: Do not delay the workload with --delay")
Signed-off-by: Changbin Du <changbin.du@huawei.com>
---
tools/perf/builtin-stat.c | 15 +++++----------
tools/perf/util/stat.c | 6 +-----
tools/perf/util/stat.h | 1 -
tools/perf/util/target.h | 12 ++++++++++++
4 files changed, 18 insertions(+), 16 deletions(-)
@@ -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 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx)
return err;
}
- if (stat_config.initial_delay) {
+ if (target.initial_delay) {
pr_info(EVLIST_DISABLED_MSG);
} else {
err = enable_counters();
@@ -926,8 +921,8 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx)
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),
@@ -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;
}
@@ -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;
@@ -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;