perf sched: Fix sched latency analysis incorrection when using 'sched:sched_wakeup'
authorChunxin Zang <zangchunxin@lixiang.com>
Tue, 28 Mar 2023 06:00:57 +0000 (14:00 +0800)
committerArnaldo Carvalho de Melo <acme@redhat.com>
Wed, 12 Apr 2023 22:30:39 +0000 (19:30 -0300)
'perf sched latency' is incorrect to get process schedule latency when
it used 'sched:sched_wakeup' to analysis perf.data.

Because 'perf record' prefers to use 'sched:sched_waking' to
'sched:sched_wakeup' since commit d566a9c2d482 ("perf sched: Prefer
sched_waking event when it exists"). It's very reasonable to evaluate
process schedule latency.

Similarly, update sched latency/map/replay to use sched_waking events.

Signed-off-by: Chunxin Zang <zangchunxin@lixiang.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230328060038.2346935-1-zangchunxin@lixiang.com
Signed-off-by: Jerry Zhou <zhouchunhua@lixiang.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools/perf/builtin-sched.c

index 96a0dceadeffd37802527d3b53a1081660e5b576..cc4ba506e1196c968f585a3439a89025289cc9ab 100644 (file)
@@ -1516,6 +1516,14 @@ static int process_sched_wakeup_event(struct perf_tool *tool,
        return 0;
 }
 
+static int process_sched_wakeup_ignore(struct perf_tool *tool __maybe_unused,
+                                     struct evsel *evsel __maybe_unused,
+                                     struct perf_sample *sample __maybe_unused,
+                                     struct machine *machine __maybe_unused)
+{
+       return 0;
+}
+
 union map_priv {
        void    *ptr;
        bool     color;
@@ -1816,10 +1824,11 @@ static int perf_sched__process_comm(struct perf_tool *tool __maybe_unused,
 
 static int perf_sched__read_events(struct perf_sched *sched)
 {
-       const struct evsel_str_handler handlers[] = {
+       struct evsel_str_handler handlers[] = {
                { "sched:sched_switch",       process_sched_switch_event, },
                { "sched:sched_stat_runtime", process_sched_runtime_event, },
                { "sched:sched_wakeup",       process_sched_wakeup_event, },
+               { "sched:sched_waking",       process_sched_wakeup_event, },
                { "sched:sched_wakeup_new",   process_sched_wakeup_event, },
                { "sched:sched_migrate_task", process_sched_migrate_task_event, },
        };
@@ -1839,6 +1848,10 @@ static int perf_sched__read_events(struct perf_sched *sched)
 
        symbol__init(&session->header.env);
 
+       /* prefer sched_waking if it is captured */
+       if (evlist__find_tracepoint_by_name(session->evlist, "sched:sched_waking"))
+               handlers[2].handler = process_sched_wakeup_ignore;
+
        if (perf_session__set_tracepoints_handlers(session, handlers))
                goto out_delete;