kernel/linux.git/tools/perf/util/header.c, branch v6.18.21

perf header: Write bpf_prog (infos|btfs)_cnt to data file

2025-11-13T20:16:33+00:00

With commit f0d0f978f3f5830a ("perf header: Don't write empty BPF/BTF info"), the write_bpf_( prog_info() | btf() ) functions exit without writing anything if env->bpf_prog.(infos| btfs)_cnt is zero. process_bpf_( prog_info() | btf() ), however, still expect a "count" value to exist in the data file. If btf information is empty, for example, process_bpf_btf will read garbage or some other data as the number of btf nodes in the data file. As a result, the data file will not be processed correctly. Instead, write the count to the data file and exit if it is zero. Fixes: f0d0f978f3f5830a ("perf header: Don't write empty BPF/BTF info") Reviewed-by: Ian Rogers Signed-off-by: Thomas Falcon Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ingo Molnar Cc: Jiri Olsa Cc: Mark Rutland Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

perf header: Clean up use of perf_env

2025-07-25T17:37:57+00:00

Always use the perf_env from the feat_fd's perf_header. Cache the value on entry to a function in `env` and use `env->` consistently in the code. Ensure the header is initialized for use in perf_session__do_write_header. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250724163302.596743-12-irogers@google.com Signed-off-by: Namhyung Kim

perf evlist: Change env variable to session

2025-07-25T17:37:56+00:00

The session holds a perf_env pointer env. In UI code container_of is used to turn the env to a session, but this assumes the session header's env is in use. Rather than a dubious container_of, hold the session in the evlist and derive the env from the session with evsel__env, perf_session__env, etc. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250724163302.596743-11-irogers@google.com Signed-off-by: Namhyung Kim

perf build-id: Change sprintf functions to snprintf

2025-07-25T17:37:13+00:00

Pass in a size argument rather than implying all build id strings must be SBUILD_ID_SIZE. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250724163302.596743-4-irogers@google.com [ fixed some build errors ] Signed-off-by: Namhyung Kim

libperf evsel: Rename own_cpus to pmu_cpus

2025-07-24T20:41:35+00:00

own_cpus is generally the cpumask from the PMU. Rename to pmu_cpus to try to make this clearer. Variable rename with no other changes. Reviewed-by: Thomas Falcon Signed-off-by: Ian Rogers Tested-by: James Clark Link: https://lore.kernel.org/r/20250719030517.1990983-7-irogers@google.com Signed-off-by: Namhyung Kim

perf header: Fix pipe mode header dumping

2025-07-03T18:22:17+00:00

The pipe mode header dumping was accidentally removed when tracing of header feature events in pipe mode was added. Minor spelling tweak to header test failure message. Fixes: 61051f9a8452 ("perf header: In pipe mode dump features without --header/-I") Signed-off-by: Ian Rogers Tested-by: Namhyung Kim Link: https://lore.kernel.org/r/20250703042000.2740640-1-irogers@google.com Signed-off-by: Namhyung Kim

perf header: Don't write empty BPF/BTF info

2025-06-25T19:37:41+00:00

If there are no values in bpf_prog_info or bpf_btf feature don't write the data into the header. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250617223356.2752099-4-irogers@google.com Signed-off-by: Namhyung Kim

perf header: Display message if BPF/BTF info is empty

2025-06-25T19:37:35+00:00

The perf.data file may contain a bpf_prog_info or bpf_btf feature. If the contents of these are empty then nothing is displayed. Rather than display nothing and not account for the file space, display an empty message. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250617223356.2752099-4-irogers@google.com Signed-off-by: Namhyung Kim

perf header: Allow tracing of attr events

2025-06-25T19:37:29+00:00

In pipe mode attr events capture the perf_event_attr. Allow their dumping as they normally start the file. Before: ``` $ perf record -o - -a sleep 1 | perf script -D -i - . ... raw event: size 272 bytes . 0000: 40 00 00 00 00 00 10 01 00 00 00 00 88 00 00 00 @............... . 0010: 00 00 00 00 00 00 00 00 a0 0f 00 00 00 00 00 00 ................ . 0020: 87 01 01 00 00 00 00 00 14 00 00 00 00 00 00 00 ................ . 0030: 01 84 05 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0090: 91 08 00 00 00 00 00 00 92 08 00 00 00 00 00 00 ................ . 00a0: 93 08 00 00 00 00 00 00 94 08 00 00 00 00 00 00 ................ . 00b0: 95 08 00 00 00 00 00 00 96 08 00 00 00 00 00 00 ................ . 00c0: 97 08 00 00 00 00 00 00 98 08 00 00 00 00 00 00 ................ . 00d0: 99 08 00 00 00 00 00 00 9a 08 00 00 00 00 00 00 ................ . 00e0: 9b 08 00 00 00 00 00 00 9c 08 00 00 00 00 00 00 ................ . 00f0: 9d 08 00 00 00 00 00 00 9e 08 00 00 00 00 00 00 ................ . 0100: 9f 08 00 00 00 00 00 00 a0 08 00 00 00 00 00 00 ................ -1 -1 0 [0x110]: PERF_RECORD_ATTR 0x110@pipe [0x110]: event: 64 ... ``` After: ``` $ perf record -o - -a sleep 1 | perf script -D -i - 0@pipe [0x110]: event: 64 . . ... raw event: size 272 bytes . 0000: 40 00 00 00 00 00 10 01 00 00 00 00 88 00 00 00 @............... . 0010: 00 00 00 00 00 00 00 00 a0 0f 00 00 00 00 00 00 ................ . 0020: 87 01 01 00 00 00 00 00 14 00 00 00 00 00 00 00 ................ . 0030: 01 84 05 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0090: 5c 08 00 00 00 00 00 00 5d 08 00 00 00 00 00 00 \.......]....... . 00a0: 5e 08 00 00 00 00 00 00 5f 08 00 00 00 00 00 00 ^......._....... . 00b0: 60 08 00 00 00 00 00 00 61 08 00 00 00 00 00 00 `.......a....... . 00c0: 62 08 00 00 00 00 00 00 63 08 00 00 00 00 00 00 b.......c....... . 00d0: 64 08 00 00 00 00 00 00 65 08 00 00 00 00 00 00 d.......e....... . 00e0: 66 08 00 00 00 00 00 00 67 08 00 00 00 00 00 00 f.......g....... . 00f0: 68 08 00 00 00 00 00 00 69 08 00 00 00 00 00 00 h.......i....... . 0100: 6a 08 00 00 00 00 00 00 6b 08 00 00 00 00 00 00 j.......k....... -1 -1 0 [0x110]: PERF_RECORD_ATTR, type = 0 (PERF_TYPE_HARDWARE), size = 136, config = 0 (PERF_COUNT_HW_CPU_CYCLES), { sample_period, sample_freq } = 4000, sample_type = IP|TID|TIME|CPU|PERIOD|IDENTIFIER, read_format = ID|LOST, disabled = 1, freq = 1, precise_ip = 3, sample_id_all = 1 0x110@pipe [0x110]: event: 64 ... ``` Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250617223356.2752099-4-irogers@google.com Signed-off-by: Namhyung Kim

perf header: In pipe mode dump features without --header/-I

2025-06-25T19:37:23+00:00

In pipe mode the header features are contained within events. While other events dump details the header features only dump if --header or -I are passed, which doesn't make sense as in pipe mode there is no perf file header. Make the printing of the information conditional on dump_trace as with other events. Before: ``` $ perf record -o - -a sleep 1 | perf script -D -i - ... 0x2c8@pipe [0x54]: event: 80 . . ... raw event: size 84 bytes . 0000: 50 00 00 00 00 00 54 00 05 00 00 00 00 00 00 00 P.....T......... . 0010: 40 00 00 00 36 2e 31 35 2e 72 63 37 2e 67 61 64 @...6.15.rc7.gad . 0020: 32 61 36 39 31 63 39 39 66 62 00 00 00 00 00 00 2a691c99fb...... . 0030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0050: 00 00 00 00 .... 0 0 0x2c8 [0x54]: PERF_RECORD_FEATURE ``` After: ``` $ perf record -o - -a sleep 1 | perf script -D -i - ... 0x2c8@pipe [0x54]: event: 80 . . ... raw event: size 84 bytes . 0000: 50 00 00 00 00 00 54 00 05 00 00 00 00 00 00 00 P.....T......... . 0010: 40 00 00 00 36 2e 31 35 2e 72 63 37 2e 67 61 64 @...6.15.rc7.gad . 0020: 32 61 36 39 31 63 39 39 66 62 00 00 00 00 00 00 2a691c99fb...... . 0030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ . 0050: 00 00 00 00 .... 0 0 0x2c8 [0x54]: PERF_RECORD_FEATURE, # perf version : 6.15.rc7.gad2a691c99fb ``` Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250617223356.2752099-4-irogers@google.com Signed-off-by: Namhyung Kim