Re: [PATCH 4/4] perf script: Output branch sample type

From: Anshuman Khandual
Date: Tue Mar 08 2022 - 00:22:23 EST




On 3/7/22 22:49, James Clark wrote:
> The type info is saved when using '-j save_type'. Output this in perf

Mentioning PERF_SAMPLE_BRANCH_CALL_STACK here as well might be better.

> script so it can be accessed by other tools or for debugging.
>
> It's appended to the end of the list of fields so any existing tools
> that split on / and access fields via an index are not affected. Also
> output '-' instead of 'N/A' when the branch type isn't saved because /
> is used as a field separator.

Did not get it. Why 'N/A' should have been used anyway ?

>
> Entries before this change look like this:
>
> 0xaaaadb350838/0xaaaadb3507a4/P/-/-/0
>
> And afterwards like this:
>
> 0xaaaadb350838/0xaaaadb3507a4/P/-/-/0/CALL
>
> or this if no type info is saved:
>
> 0x7fb57586df6b/0x7fb5758731f0/P/-/-/143/-

143 ?

>
> Signed-off-by: James Clark <james.clark@xxxxxxx>
> ---
> tools/perf/builtin-script.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
> index fac2e9470926..5e4a262a6825 100644
> --- a/tools/perf/builtin-script.c
> +++ b/tools/perf/builtin-script.c
> @@ -859,11 +859,12 @@ mispred_str(struct branch_entry *br)
>
> static int print_bstack_flags(FILE *fp, struct branch_entry *br)
> {
> - return fprintf(fp, "/%c/%c/%c/%d ",
> + return fprintf(fp, "/%c/%c/%c/%d/%s ",
> mispred_str(br),
> br->flags.in_tx ? 'X' : '-',
> br->flags.abort ? 'A' : '-',
> - br->flags.cycles);
> + br->flags.cycles,
> + br->flags.type ? branch_type_name(br->flags.type) : "-");
> }
>
> static int perf_sample__fprintf_brstack(struct perf_sample *sample,


LGTM but as mentioned before, I hope this does not affect any existing
parsing tools.