# Re: \[PATCH 17/17\] vsprintf: rework bitmap\_list\_string

- From: Andy Shevchenko \<hidden\>
- Date: 2021-08-15 11:10:30 
- List: linux-arch
- Page: https://ratatoskr.run/linux-arch/2021/08/1478163
- Thread: https://ratatoskr.run/linux-mm/2021/08/1477967/t.md

```text
On Sun, Aug 15, 2021 at 12:21 AM Yury Norov [ref] wrote:
>
> bitmap_list_string() is very ineffective when printing bitmaps with long
> ranges of set bits because it calls find_next_bit for each bit in the
> bitmap.  We can do better by detecting ranges of set bits.
>
> In my environment, before/after is 943008/31008 ns.

I would add a couple of words, maybe in parentheses, to describe what
your environment is.

...

> +               buf = number(++buf, end, rtop - 1, default_dec_spec);

++buf is a bit confusing here. Since you will rewrite the buf value
anyway, I would write the parameter as buf + 1.

-- 
With Best Regards,
Andy Shevchenko
```