Extend -D,--delay option with -1 value to start monitoring with
events disabled to be enabled later by enable command provided
via control file descriptor.
Signed-off-by: Alexey Budankov <alexey.budan...@linux.intel.com>
---
tools/perf/Documentation/perf-stat.txt | 5 +++--
tools/perf/builtin-stat.c | 18 ++++++++++++++----
tools/perf/util/evlist.h | 3 +++
tools/perf/util/stat.h | 2 +-
4 files changed, 21 insertions(+), 7 deletions(-)
diff --git a/tools/perf/Documentation/perf-stat.txt
b/tools/perf/Documentation/perf-stat.txt
index 3fb5028aef08..b4d2434584f5 100644
--- a/tools/perf/Documentation/perf-stat.txt
+++ b/tools/perf/Documentation/perf-stat.txt
@@ -226,8 +226,9 @@ mode, use --per-node in addition to -a. (system-wide).
-D msecs::
--delay msecs::
-After starting the program, wait msecs before measuring. This is useful to
-filter out the startup phase of the program, which is often very different.
+After starting the program, wait msecs before measuring (-1: start with events
+disabled). This is useful to filter out the startup phase of the program,
+which is often very different.
-T::
--transaction::
diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index ef2682a87491..70b48a279b75 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -441,16 +441,26 @@ static bool process_timeout(bool timeout, unsigned int
interval, int *times)
static void enable_counters(void)
{
- if (stat_config.initial_delay)
+ if (stat_config.initial_delay < 0) {
+ pr_info(EVLIST_DISABLED_MSG);
+ return;
+ }
+
+ if (stat_config.initial_delay > 0) {
+ pr_info(EVLIST_DISABLED_MSG);
usleep(stat_config.initial_delay * USEC_PER_MSEC);
+ }
/*
* 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) || stat_config.initial_delay)
+ if (!target__none(&target) || stat_config.initial_delay) {
evlist__enable(evsel_list);
+ if (stat_config.initial_delay > 0)
+ pr_info(EVLIST_ENABLED_MSG);
+ }
}
static void disable_counters(void)
@@ -1001,8 +1011,8 @@ 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_UINTEGER('D', "delay", &stat_config.initial_delay,
- "ms to wait before starting measurement after program
start"),
+ OPT_INTEGER('D', "delay", &stat_config.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),
OPT_BOOLEAN(0, "topdown", &topdown_run,
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index bccf0a970371..7c3726a685f5 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -377,4 +377,7 @@ int evlist__initialize_ctlfd(struct evlist *evlist, int
ctl_fd, int ctl_fd_ack);
int evlist__finalize_ctlfd(struct evlist *evlist);
int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd);
+#define EVLIST_ENABLED_MSG "Events enabled\n"
+#define EVLIST_DISABLED_MSG "Events disabled\n"
+
#endif /* __PERF_EVLIST_H */
diff --git a/tools/perf/util/stat.h b/tools/perf/util/stat.h
index a5604a20bdca..b00d64f0ca26 100644
--- a/tools/perf/util/stat.h
+++ b/tools/perf/util/stat.h
@@ -114,7 +114,7 @@ struct perf_stat_config {
FILE *output;
unsigned int interval;
unsigned int timeout;
- unsigned int initial_delay;
+ int initial_delay;
unsigned int unit_width;
unsigned int metric_only_len;
int times;
--
2.24.1
