On Mon, Oct 07, 2019 at 04:17:32PM -0400, Dennis Zhou wrote:
> Bitmaps are fairly popular for their space efficiency, but we don't have
> generic iterators available. Make percpu's bitmap region iterators
> available to everyone.
>
> Signed-off-by: Dennis Zhou <dennis@xxxxxxxxxx>
> ---
> include/linux/bitmap.h | 35 ++++++++++++++++++++++++
> mm/percpu.c | 61 +++++++++++-------------------------------
> 2 files changed, 51 insertions(+), 45 deletions(-)
>
> diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
> index 90528f12bdfa..9b0664f36808 100644
> --- a/include/linux/bitmap.h
> +++ b/include/linux/bitmap.h
> @@ -437,6 +437,41 @@ static inline int bitmap_parse(const char *buf, unsigned int buflen,
> return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
> }
>
> +static inline void bitmap_next_clear_region(unsigned long *bitmap,
> + unsigned int *rs, unsigned int *re,
> + unsigned int end)
> +{
> + *rs = find_next_zero_bit(bitmap, end, *rs);
> + *re = find_next_bit(bitmap, end, *rs + 1);
> +}
> +
> +static inline void bitmap_next_set_region(unsigned long *bitmap,
> + unsigned int *rs, unsigned int *re,
> + unsigned int end)
> +{
> + *rs = find_next_bit(bitmap, end, *rs);
> + *re = find_next_zero_bit(bitmap, end, *rs + 1);
> +}
> +
> +/*
> + * Bitmap region iterators. Iterates over the bitmap between [@start, @end).
Gonna be that guy here, should be '[@start, @end]'
Reviewed-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
Thanks,
Josef
