perf script: Display off-cpu samples correctly

No PERF_SAMPLE_CALLCHAIN in sample_type, but 'perf script' needs to
display a callchain, have to specify manually.

Also, prefer displaying a callchain:

 gvfs-afc-volume    2267 [001] 3829232.955656: 1001115340 offcpu-time:
            77f05292603f __pselect+0xbf (/usr/lib/x86_64-linux-gnu/libc.so.6)
            77f052a1801c [unknown] (/usr/lib/x86_64-linux-gnu/libusbmuxd-2.0.so.6.0.0)
            77f052a18d45 [unknown] (/usr/lib/x86_64-linux-gnu/libusbmuxd-2.0.so.6.0.0)
            77f05289ca94 start_thread+0x384 (/usr/lib/x86_64-linux-gnu/libc.so.6)
            77f052929c3c clone3+0x2c (/usr/lib/x86_64-linux-gnu/libc.so.6)

to a raw binary BPF output:

  BPF output: 0000: dd 08 00 00 db 08 00 00  <DD>...<DB>...
	  0008: cc ce ab 3b 00 00 00 00  <CC>Ϋ;....
	  0010: 06 00 00 00 00 00 00 00  ........
	  0018: 00 fe ff ff ff ff ff ff  .<FE><FF><FF><FF><FF><FF><FF>
	  0020: 3f 60 92 52 f0 77 00 00  ?`.R<F0>w..
	  0028: 1c 80 a1 52 f0 77 00 00  ..<A1>R<F0>w..
	  0030: 45 8d a1 52 f0 77 00 00  E.<A1>R<F0>w..
	  0038: 94 ca 89 52 f0 77 00 00  .<CA>.R<F0>w..
	  0040: 3c 9c 92 52 f0 77 00 00  <..R<F0>w..
	  0048: 00 00 00 00 00 00 00 00  ........
	  0050: 00 00 00 00              ....

Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Howard Chu <howardchu95@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Gautam Menghani <gautam@linux.ibm.com>
Tested-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20241108204137.2444151-9-howardchu95@gmail.com
Link: https://lore.kernel.org/r/20250501022809.449767-8-howardchu95@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 9b16df881af8c80e4b987bbe0b9d044ae06d4df2..6c3bf74dd78c3967645cf4f8aaca2b4a7dccfaf5 100644 (file)
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -680,7 +680,7 @@ static int perf_session__check_output_opt(struct perf_session *session)
 
                evlist__for_each_entry(session->evlist, evsel) {
                        not_pipe = true;
-                       if (evsel__has_callchain(evsel)) {
+                       if (evsel__has_callchain(evsel) || evsel__is_offcpu_event(evsel)) {
                                use_callchain = true;
                                break;
                        }
@@ -2295,7 +2295,7 @@ static void process_event(struct perf_script *script,
        else if (PRINT_FIELD(BRSTACKOFF))
                perf_sample__fprintf_brstackoff(sample, thread, evsel, fp);
 
-       if (evsel__is_bpf_output(evsel) && PRINT_FIELD(BPF_OUTPUT))
+       if (evsel__is_bpf_output(evsel) && !evsel__is_offcpu_event(evsel) && PRINT_FIELD(BPF_OUTPUT))
                perf_sample__fprintf_bpf_output(sample, fp);
        perf_sample__fprintf_insn(sample, evsel, attr, thread, machine, fp, al);