Re: [PATCH 17/17] vsprintf: rework bitmap_list_string

On Sun, Aug 15, 2021 at 02:09:45PM +0300, Andy Shevchenko wrote:

On Sun, Aug 15, 2021 at 12:21 AM Yury Norov [off-list ref] wrote:

quoted

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.

...

quoted

+               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.

Agree, it's sloppy. I'll  send the patch by tomorrow.