Re: [PATCH] perf trace: Remove return value of trace__fprintf_tp_fields

[Howard Chu]

Hello Benjamin,

On Thu, Dec 12, 2024 at 7:56 PM Benjamin Peterson <benjamin@xxxxxxxxxxx> wrote:
>
> The return value of this function was meaningless and therefore ignored by
> the caller. Remove it.
>
> Signed-off-by: Benjamin Peterson <benjamin@xxxxxxxxxxx>
> ---
> This is a small followup cleanup to my earlier commit 5fb8e56542a3 ("perf
> trace: avoid garbage when not printing a trace event's arguments").
> ---
>  tools/perf/builtin-trace.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
> index 6a1a128fe645014d0347ad4ec3e0c9e77ec59aee..246be66fd59a4b9d76e4d3c42b68d0a444ca366a 100644
> --- a/tools/perf/builtin-trace.c
> +++ b/tools/perf/builtin-trace.c
> @@ -3022,8 +3022,8 @@ static void bpf_output__fprintf(struct trace *trace,
>         ++trace->nr_events_printed;
>  }
>
> -static size_t trace__fprintf_tp_fields(struct trace *trace, struct evsel *evsel, struct perf_sample *sample,
> -                                      struct thread *thread, void *augmented_args, int augmented_args_size)
> +static void trace__fprintf_tp_fields(struct trace *trace, struct evsel *evsel, struct perf_sample *sample,
> +                                    struct thread *thread, void *augmented_args, int augmented_args_size)
>  {
>         char bf[2048];
>         size_t size = sizeof(bf);
> @@ -3088,7 +3088,7 @@ static size_t trace__fprintf_tp_fields(struct trace *trace, struct evsel *evsel,
>                 printed += syscall_arg_fmt__scnprintf_val(arg, bf + printed, size - printed, &syscall_arg, val);
>         }
>
> -       return printed + fprintf(trace->output, "%.*s", (int)printed, bf);
> +       fprintf(trace->output, "%.*s", (int)printed, bf);
>  }
>
>  static int trace__event_handler(struct trace *trace, struct evsel *evsel,
>
> ---
> base-commit: eefa7a9c069908412f8f5d15833901d1b46ae1b2
> change-id: 20241212-void-fprintf_tp_fields-8aaae2f5525f
>
> Best regards,
> --
> Benjamin Peterson <benjamin@xxxxxxxxxxx>
>
>

Thank you for the follow-up patch, LGTM. Built and tested.

perf $ ./perf test "perf trace"
109: perf trace enum augmentation tests                              : Ok
110: perf trace exit race                                            : Ok

Reviewed-by: Howard Chu <howardchu95@xxxxxxxxx>

Thanks,
Howard