[PATCH 0/5] perf record: Tracking side-band events for all CPUs when tracing selected CPUs

[Yang Jihong]

User space tasks can migrate between CPUs, we need to track side-band
events for all CPUs.

The specific scenarios are as follows:

         CPU0                                 CPU1
  perf record -C 0 start
                              taskA starts to be created and executed
                                -> PERF_RECORD_COMM and PERF_RECORD_MMAP
                                   events only deliver to CPU1
                              ......
                                |
                          migrate to CPU0
                                |
  Running on CPU0    <----------/
  ...

  perf record -C 0 stop

Now perf samples the PC of taskA. However, perf does not record the
PERF_RECORD_COMM and PERF_RECORD_COMM events of taskA.
Therefore, the comm and symbols of taskA cannot be parsed.

The sys_perf_event_open invoked is as follows:

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

1. patch1 and patch2 are pre-patch and are used to provide two helpers.
   One is used to modify cpu_maps,
   and the other is used to search for dummy tracking evsel in the evlist.
2. patch3 is the main patch, track side-band events for all CPUs when
   tracing selected CPUs
3. patch4 adds the corresponding test case.
4. patch5 is code optimization.

Yang Jihong (5):
  perf evlist: Export perf_evlist__propagate_maps()
  perf evlist: Add evlist__findnew_tracking_event() helper
  perf record: Tracking side-band events for all CPUs when tracing
    selected CPUs
  perf test: Add test case for record tracking
  perf record: All config tracking are integrated into
    record__config_tracking_events()

 tools/lib/perf/evlist.c                   | 23 +++----
 tools/lib/perf/include/perf/evlist.h      |  2 +
 tools/perf/builtin-record.c               | 74 ++++++++++++++---------
 tools/perf/tests/shell/record_tracking.sh | 44 ++++++++++++++
 tools/perf/util/evlist.c                  | 17 ++++++
 tools/perf/util/evlist.h                  |  1 +
 6 files changed, 120 insertions(+), 41 deletions(-)
 create mode 100755 tools/perf/tests/shell/record_tracking.sh

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2.30.GIT