Messages in this thread | | | From | Yang Jihong <> | Subject | [PATCH v4 0/7] perf record: Track sideband events for all CPUs when tracing selected CPUs | Date | Wed, 2 Aug 2023 07:49:41 +0000 |
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User space tasks can migrate between CPUs, track sideband 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 (PERF_TYPE_SOFTWARE) size 136 config 0 (PERF_COUNT_SW_CPU_CLOCK) { sample_period, sample_freq } 4000 sample_type IP|TID|TIME|CPU|PERIOD|IDENTIFIER 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:u ------------------------------------------------------------ perf_event_attr: type 1 (PERF_TYPE_SOFTWARE) size 136 config 0x9 (PERF_COUNT_SW_DUMMY) { sample_period, sample_freq } 1 sample_type IP|TID|TIME|CPU|IDENTIFIER read_format ID|LOST inherit 1 exclude_kernel 1 exclude_hv 1 mmap 1 comm 1 task 1 sample_id_all 1 exclude_guest 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>
Changes since_v3: - Check fall_kernel, all_user, and dummy or exclude_user when determining whether system wide is required.
Changes since_v2: - Rename record_tracking.sh to record_sideband.sh in tools/perf/tests/shell. - Remove "perf evlist: Skip dummy event sample_type check for evlist_config" patch. - Add opts->all_kernel check in record__config_tracking_events(). - Add perf_event_attr test for record selected CPUs exclude_user. - Update base-record & system-wide-dummy sample_type attr expected values for test-record-C0.
Changes since v1: - Add perf_evlist__go_system_wide() via internal/evlist.h instead of exporting perf_evlist__propagate_maps(). - Use evlist__add_aux_dummy() instead of evlist__add_dummy() in evlist__findnew_tracking_event(). - Add a parameter in evlist__findnew_tracking_event() to deal with system_wide inside. - Add sideband for all CPUs when tracing selected CPUs comments on the perf record man page. - Use "sideband events" instead of "tracking events". - Adjust the patches Sequence. - Add patch5 to skip dummy event sample_type check for evlist_config. - Add patch6 to update system-wide-dummy attr values for perf test.
Yang Jihong (7): perf evlist: Add perf_evlist__go_system_wide() helper perf evlist: Add evlist__findnew_tracking_event() helper perf record: Move setting dummy tracking before record__init_thread_masks() perf record: Track sideband events for all CPUs when tracing selected CPUs perf test: Update base-record & system-wide-dummy attr expected values for test-record-C0 perf test: Add test case for record sideband events perf test: Add perf_event_attr test for record selected CPUs exclude_user
tools/lib/perf/evlist.c | 9 ++ tools/lib/perf/include/internal/evlist.h | 2 + tools/perf/Documentation/perf-record.txt | 3 + tools/perf/builtin-record.c | 107 +++++++++++++----- tools/perf/tests/attr/system-wide-dummy | 14 ++- tools/perf/tests/attr/test-record-C0 | 4 +- .../perf/tests/attr/test-record-C0-all-kernel | 32 ++++++ tools/perf/tests/shell/record_sideband.sh | 44 +++++++ tools/perf/util/evlist.c | 18 +++ tools/perf/util/evlist.h | 1 + 10 files changed, 199 insertions(+), 35 deletions(-) create mode 100644 tools/perf/tests/attr/test-record-C0-all-kernel create mode 100755 tools/perf/tests/shell/record_sideband.sh
-- 2.30.GIT
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