perf annotate: Display the branch counter histogram

Display the branch counter histogram in the annotation view.

Press 'B' to display the branch counter's abbreviation list as well.

  Samples: 1M of events 'anon group { branch-instructions:ppp, branch-misses }',
  4000 Hz, Event count (approx.):
  f3  /home/sdp/test/tchain_edit [Percent: local period]
  Percent       │ IPC Cycle       Branch Counter (Average IPC: 1.39, IPC Coverage: 29.4%)
                │                                     0000000000401755 <f3>:
    0.00   0.00 │                                       endbr64
                │                                       push    %rbp
                │                                       mov     %rsp,%rbp
                │                                       movl    $0x0,-0x4(%rbp)
    0.00   0.00 │1.33     3          |A   |-   |      ↓ jmp     25
   11.03  11.03 │                                 11:   mov     -0x4(%rbp),%eax
                │                                       and     $0x1,%eax
                │                                       test    %eax,%eax
   17.13  17.13 │2.41     1          |A   |-   |      ↓ je      21
                │                                       addl    $0x1,-0x4(%rbp)
   21.84  21.84 │2.22     2          |AA  |-   |      ↓ jmp     25
   17.13  17.13 │                                 21:   addl    $0x1,-0x4(%rbp)
   21.84  21.84 │                                 25:   cmpl    $0x270f,-0x4(%rbp)
   11.03  11.03 │0.61     3          |A   |-   |      ↑ jle     11
                │                                       nop
                │                                       pop     %rbp
    0.00   0.00 │0.24    20          |AA  |B   |      ← ret

Originally-by: Tinghao Zhang <[email protected]>
Reviewed-by: Andi Kleen <[email protected]>
Signed-off-by: Kan Liang <[email protected]>
Acked-by: Namhyung Kim <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

1 files changed, 7 insertions, 3 deletions

diff --git a/tools/perf/builtin-annotate.c b/tools/perf/builtin-annotate.c
index 9b4a8a379b5b..3dc6197ef3fa 100644
--- a/tools/perf/builtin-annotate.c
+++ b/tools/perf/builtin-annotate.c
@@ -927,11 +927,15 @@ int cmd_annotate(int argc, const char **argv)
 		sort_order = "dso,symbol";
 
 	/*
-	 * Set SORT_MODE__BRANCH so that annotate display IPC/Cycle
-	 * if branch info is in perf data in TUI mode.
+	 * Set SORT_MODE__BRANCH so that annotate displays IPC/Cycle and
+	 * branch counters, if the corresponding branch info is available
+	 * in the perf data in the TUI mode.
 	 */
-	if ((use_browser == 1 || annotate.use_stdio2) && annotate.has_br_stack)
+	if ((use_browser == 1 || annotate.use_stdio2) && annotate.has_br_stack) {
 		sort__mode = SORT_MODE__BRANCH;
+		if (annotate.session->evlist->nr_br_cntr > 0)
+			annotate_opts.show_br_cntr = true;
+	}
 
 	if (setup_sorting(NULL) < 0)
 		usage_with_options(annotate_usage, options);