From 448ce0e6ea93ae99e0b36055e5f5a3f723fe3665 Mon Sep 17 00:00:00 2001
From: Gang Li <ligang.bdlg@bytedance.com>
Date: Wed, 22 Jun 2022 11:00:37 +0800
Subject: [PATCH] perf stat: Enable ignore_missing_thread

perf already support ignore_missing_thread for -p, but not yet
applied to `perf stat -p <pid>`. This patch enables ignore_missing_thread
for `perf stat -p <pid>`.

Committer notes:

And here is a refresher about the 'ignore_missing_thread' knob, from a
previous patch using it:

  ca8000684ec4e66f ("perf evsel: Enable ignore_missing_thread for pid option")

  ---
    While monitoring a multithread process with pid option, perf sometimes
    may return sys_perf_event_open failure with 3(No such process) if any of
    the process's threads die before we open the event. However, we want
    perf continue monitoring the remaining threads and do not exit with
    error.
  ---

Signed-off-by: Gang Li <ligang.bdlg@bytedance.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.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/20220622030037.15005-1-ligang.bdlg@bytedance.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/builtin-stat.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 4ce87a8eb7d7e..d2ecd4d296243 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -2586,6 +2586,8 @@ int cmd_stat(int argc, const char **argv)
 	if (evlist__initialize_ctlfd(evsel_list, stat_config.ctl_fd, stat_config.ctl_fd_ack))
 		goto out;
 
+	/* Enable ignoring missing threads when -p option is defined. */
+	evlist__first(evsel_list)->ignore_missing_thread = target.pid;
 	status = 0;
 	for (run_idx = 0; forever || run_idx < stat_config.run_count; run_idx++) {
 		if (stat_config.run_count != 1 && verbose > 0)
-- 
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