Re: [PATCH] media: mc: mc-entity.c: Use bitmap_zalloc() when applicable

From: Kieran Bingham
Date: Thu Dec 02 2021 - 07:38:19 EST


Quoting Christophe JAILLET (2021-12-01 22:19:40)
> 'ent_enum->bmap' is a bitmap. So use 'bitmap_zalloc()' to simplify
> code, improve the semantic and avoid some open-coded arithmetic in
> allocator arguments.
>
> Also change the corresponding 'kfree()' into 'bitmap_free()' to keep
> consistency.
>
> While at it, remove a useless 'bitmap_zero()'.

Ah, yes kcalloc zeros memory, so it is doing a redundant clear as well.
Changing to bitmap_zalloc looks a lot better though.

Reviewed-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>

>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> ---
> drivers/media/mc/mc-entity.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/media/mc/mc-entity.c b/drivers/media/mc/mc-entity.c
> index c02340698ad6..b411f9796191 100644
> --- a/drivers/media/mc/mc-entity.c
> +++ b/drivers/media/mc/mc-entity.c
> @@ -48,12 +48,10 @@ __must_check int __media_entity_enum_init(struct media_entity_enum *ent_enum,
> int idx_max)
> {
> idx_max = ALIGN(idx_max, BITS_PER_LONG);
> - ent_enum->bmap = kcalloc(idx_max / BITS_PER_LONG, sizeof(long),
> - GFP_KERNEL);
> + ent_enum->bmap = bitmap_zalloc(idx_max, GFP_KERNEL);
> if (!ent_enum->bmap)
> return -ENOMEM;
>
> - bitmap_zero(ent_enum->bmap, idx_max);
> ent_enum->idx_max = idx_max;
>
> return 0;
> @@ -62,7 +60,7 @@ EXPORT_SYMBOL_GPL(__media_entity_enum_init);
>
> void media_entity_enum_cleanup(struct media_entity_enum *ent_enum)
> {
> - kfree(ent_enum->bmap);
> + bitmap_free(ent_enum->bmap);
> }
> EXPORT_SYMBOL_GPL(media_entity_enum_cleanup);
>
> --
> 2.30.2
>