diff options
Diffstat (limited to 'tools/perf/builtin-record.c')
| -rw-r--r-- | tools/perf/builtin-record.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index cda7e6a7b45d..9af3f21fd015 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -161,6 +161,7 @@ struct record { struct evlist *sb_evlist; pthread_t thread_id; int realtime_prio; + bool latency; bool switch_output_event_set; bool no_buildid; bool no_buildid_set; @@ -3373,6 +3374,9 @@ static struct option __record_options[] = { parse_events_option), OPT_CALLBACK(0, "filter", &record.evlist, "filter", "event filter", parse_filter), + OPT_BOOLEAN(0, "latency", &record.latency, + "Enable data collection for latency profiling.\n" + "\t\t\t Use perf report --latency for latency-centric profile."), OPT_CALLBACK_NOOPT(0, "exclude-perf", &record.evlist, NULL, "don't record events from perf itself", exclude_perf), @@ -4019,6 +4023,22 @@ int cmd_record(int argc, const char **argv) } + if (record.latency) { + /* + * There is no fundamental reason why latency profiling + * can't work for system-wide mode, but exact semantics + * and details are to be defined. + * See the following thread for details: + * https://lore.kernel.org/all/Z4XDJyvjiie3howF@google.com/ + */ + if (record.opts.target.system_wide) { + pr_err("Failed: latency profiling is not supported with system-wide collection.\n"); + err = -EINVAL; + goto out_opts; + } + record.opts.record_switch_events = true; + } + if (rec->buildid_mmap) { if (!perf_can_record_build_id()) { pr_err("Failed: no support to record build id in mmap events, update your kernel.\n"); |