[PATCH 5/5] perf record: All config tracking are integrated into record__config_tracking_events()

[Yang Jihong]

The current perf-record also config tracking events in record__open(),
move it to the record__config_tracking_events().

The sys_perf_event_open invoked is as follows:

  # perf --debug verbose=3 record -e cpu-clock -D 100 true
  <SNIP>
  Opening: cpu-clock
  ------------------------------------------------------------
  perf_event_attr:
    type                             1
    size                             136
    { sample_period, sample_freq }   4000
    sample_type                      IP|TID|TIME|ID|PERIOD
    read_format                      ID|LOST
    disabled                         1
    inherit                          1
    freq                             1
    sample_id_all                    1
    exclude_guest                    1
  ------------------------------------------------------------
  sys_perf_event_open: pid 3569  cpu 0  group_fd -1  flags 0x8 = 5
  sys_perf_event_open: pid 3569  cpu 1  group_fd -1  flags 0x8 = 6
  sys_perf_event_open: pid 3569  cpu 2  group_fd -1  flags 0x8 = 7
  sys_perf_event_open: pid 3569  cpu 3  group_fd -1  flags 0x8 = 9
  sys_perf_event_open: pid 3569  cpu 4  group_fd -1  flags 0x8 = 10
  sys_perf_event_open: pid 3569  cpu 5  group_fd -1  flags 0x8 = 11
  sys_perf_event_open: pid 3569  cpu 6  group_fd -1  flags 0x8 = 12
  sys_perf_event_open: pid 3569  cpu 7  group_fd -1  flags 0x8 = 13
  Opening: dummy:HG
  ------------------------------------------------------------
  perf_event_attr:
    type                             1
    size                             136
    config                           0x9
    { sample_period, sample_freq }   4000
    sample_type                      IP|TID|TIME|ID|PERIOD
    read_format                      ID|LOST
    disabled                         1
    inherit                          1
    mmap                             1
    comm                             1
    freq                             1
    enable_on_exec                   1
    task                             1
    sample_id_all                    1
    mmap2                            1
    comm_exec                        1
    ksymbol                          1
    bpf_event                        1
  ------------------------------------------------------------
  sys_perf_event_open: pid 3569  cpu 0  group_fd -1  flags 0x8 = 14
  sys_perf_event_open: pid 3569  cpu 1  group_fd -1  flags 0x8 = 15
  sys_perf_event_open: pid 3569  cpu 2  group_fd -1  flags 0x8 = 16
  sys_perf_event_open: pid 3569  cpu 3  group_fd -1  flags 0x8 = 17
  sys_perf_event_open: pid 3569  cpu 4  group_fd -1  flags 0x8 = 18
  sys_perf_event_open: pid 3569  cpu 5  group_fd -1  flags 0x8 = 19
  sys_perf_event_open: pid 3569  cpu 6  group_fd -1  flags 0x8 = 20
  sys_perf_event_open: pid 3569  cpu 7  group_fd -1  flags 0x8 = 21
  <SNIP>

Signed-off-by: Yang Jihong <yangjihong1@xxxxxxxxxx>
---
 tools/perf/builtin-record.c | 46 ++++++++++++++++---------------------
 1 file changed, 20 insertions(+), 26 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 69e0d8c75aab..1e21f64e4cfa 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -915,15 +915,31 @@ static int record__config_tracking_events(struct record *rec)
 	struct record_opts *opts = &rec->opts;
 
 	/*
-	 * User space tasks can migrate between CPUs, so when tracing
-	 * selected CPUs, sideband for all CPUs is still needed.
+	 * For initial_delay, system wide or a hybrid system, we need to add a
+	 * dummy event so that we can track PERF_RECORD_MMAP to cover the delay
+	 * of waiting or event synthesis.
 	 */
-	if (opts->target.cpu_list) {
+	if (opts->target.initial_delay || target__has_cpu(&opts->target) ||
+	    perf_pmus__num_core_pmus() > 1) {
 		evsel = evlist__findnew_tracking_event(evlist);
 		if (!evsel)
 			return -ENOMEM;
 
-		if (!evsel->core.system_wide) {
+		/*
+		 * Enable the dummy event when the process is forked for
+		 * initial_delay, immediately for system wide.
+		 */
+		if (opts->target.initial_delay && !evsel->immediate &&
+		    !target__has_cpu(&opts->target))
+			evsel->core.attr.enable_on_exec = 1;
+		else
+			evsel->immediate = 1;
+
+		/*
+		 * User space tasks can migrate between CPUs, so when tracing
+		 * selected CPUs, sideband for all CPUs is still needed.
+		 */
+		if (opts->target.cpu_list && !evsel->core.system_wide) {
 			evsel->core.system_wide = true;
 			evsel__set_sample_bit(evsel, TIME);
 			perf_evlist__propagate_maps(&evlist->core, &evsel->core);
@@ -1313,28 +1329,6 @@ static int record__open(struct record *rec)
 	struct record_opts *opts = &rec->opts;
 	int rc = 0;
 
-	/*
-	 * For initial_delay, system wide or a hybrid system, we need to add a
-	 * dummy event so that we can track PERF_RECORD_MMAP to cover the delay
-	 * of waiting or event synthesis.
-	 */
-	if (opts->target.initial_delay || target__has_cpu(&opts->target) ||
-	    perf_pmus__num_core_pmus() > 1) {
-		pos = evlist__findnew_tracking_event(evlist);
-		if (!pos)
-			return -ENOMEM;
-
-		/*
-		 * Enable the dummy event when the process is forked for
-		 * initial_delay, immediately for system wide.
-		 */
-		if (opts->target.initial_delay && !pos->immediate &&
-		    !target__has_cpu(&opts->target))
-			pos->core.attr.enable_on_exec = 1;
-		else
-			pos->immediate = 1;
-	}
-
 	evlist__config(evlist, opts, &callchain_param);
 
 	evlist__for_each_entry(evlist, pos) {
-- 
2.30.GIT