Re: [PATCH 04/10] ext4: use is_power_of_2 helper in ext4_mb_regular_allocator

From: IBM
Date: Fri Jul 21 2023 - 11:38:36 EST


Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> writes:

> Use intuitive is_power_of_2 helper in ext4_mb_regular_allocator.
>
> Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx>
> ---
> fs/ext4/mballoc.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>

Looks good to me. Feel free to add:

Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx>

> diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
> index 4031f8e2a660..b838944b5f09 100644
> --- a/fs/ext4/mballoc.c
> +++ b/fs/ext4/mballoc.c
> @@ -2795,10 +2795,7 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
> * requests upto maximum buddy size we have constructed.
> */
> if (i >= sbi->s_mb_order2_reqs && i <= MB_NUM_ORDERS(sb)) {
> - /*
> - * This should tell if fe_len is exactly power of 2
> - */
> - if ((ac->ac_g_ex.fe_len & (~(1 << (i - 1)))) == 0)
> + if (is_power_of_2(ac->ac_g_ex.fe_len))
> ac->ac_2order = array_index_nospec(i - 1,
> MB_NUM_ORDERS(sb));
> }
> --
> 2.30.0