Re: [PATCH v18 01/14] bitops: Introduce the for_each_set_clump8 macro

From: Andrew Morton
Date: Wed Oct 09 2019 - 17:19:05 EST


On Wed, 9 Oct 2019 13:14:37 -0400 William Breathitt Gray <vilhelm.gray@xxxxxxxxx> wrote:

> This macro iterates for each 8-bit group of bits (clump) with set bits,
> within a bitmap memory region. For each iteration, "start" is set to the
> bit offset of the found clump, while the respective clump value is
> stored to the location pointed by "clump". Additionally, the
> bitmap_get_value8 and bitmap_set_value8 functions are introduced to
> respectively get and set an 8-bit value in a bitmap memory region.
>
> ...
>
> +#define for_each_set_clump8(start, clump, bits, size) \
> + for ((start) = find_first_clump8(&(clump), (bits), (size)); \
> + (start) < (size); \
> + (start) = find_next_clump8(&(clump), (bits), (size), (start) + 8))
> +

It wouldn't hurt to give this some documentation. In kerneldoc form, I
guess.