Re: [PATCH v2] perf annotate: allow 's' on source code lines

[Ian Rogers <irogers@google.com>]

On Thu, Jun 24, 2021 at 3:37 PM Riccardo Mancini <rickyman7@gmail.com> wrote:
>
> In perf annotate, when 's' is pressed on a line containing
> source code, it shows the message "Only available for assembly
> lines".
> This patch gets rid of the error, moving the cursr to the next
> available asm line (or the closest previous one if no asm line
> is found moving forwards), before hiding source code lines.
>
> Changes in v2:
>  - handle case of no asm line found in
>    annotate_browser__find_next_asm_line by returning NULL and
>    handling error in caller.
>
> Signed-off-by: Riccardo Mancini <rickyman7@gmail.com>

Acked-by: Ian Rogers <irogers@google.com>

> ---
>  tools/perf/ui/browsers/annotate.c | 32 ++++++++++++++++++++++++++++---
>  1 file changed, 29 insertions(+), 3 deletions(-)
>
> diff --git a/tools/perf/ui/browsers/annotate.c b/tools/perf/ui/browsers/annotate.c
> index ad0a70f0edaf..f5509a958e38 100644
> --- a/tools/perf/ui/browsers/annotate.c
> +++ b/tools/perf/ui/browsers/annotate.c
> @@ -343,6 +343,29 @@ static void annotate_browser__calc_percent(struct annotate_browser *browser,
>         browser->curr_hot = rb_last(&browser->entries);
>  }
>
> +static struct annotation_line *annotate_browser__find_next_asm_line(
> +                                       struct annotate_browser *browser,
> +                                       struct annotation_line *al)
> +{
> +       struct annotation_line *it = al;
> +
> +       /* find next asm line */
> +       list_for_each_entry_continue(it, browser->b.top, node) {
> +               if (it->idx_asm >= 0)
> +                       return it;
> +       }
> +
> +       /* no asm line found forwards, try backwards */
> +       it = al;
> +       list_for_each_entry_continue_reverse(it, browser->b.top, node) {
> +               if (it->idx_asm >= 0)
> +                       return it;
> +       }
> +
> +       /* There are no asm lines */
> +       return NULL;
> +}
> +
>  static bool annotate_browser__toggle_source(struct annotate_browser *browser)
>  {
>         struct annotation *notes = browser__annotation(&browser->b);
> @@ -363,9 +386,12 @@ static bool annotate_browser__toggle_source(struct annotate_browser *browser)
>                 browser->b.index = al->idx;
>         } else {
>                 if (al->idx_asm < 0) {
> -                       ui_helpline__puts("Only available for assembly lines.");
> -                       browser->b.seek(&browser->b, -offset, SEEK_CUR);
> -                       return false;
> +                       /* move cursor to next asm line */

comment nit, perhaps prefer "closest" rather than "next" due to
searching backward.

Thanks,
Ian

> +                       al = annotate_browser__find_next_asm_line(browser, al);
> +                       if (!al) {
> +                               browser->b.seek(&browser->b, -offset, SEEK_CUR);
> +                               return false;
> +                       }
>                 }
>
>                 if (al->idx_asm < offset)
> --
> 2.31.1
>