On Sat 21-09-19 09:56:28, Chengguang Xu wrote:
> Code cleanup for hash bits calculation by
> calling rounddown_pow_of_two() and ilog2()
>
> Signed-off-by: Chengguang Xu <cgxu...@zoho.com.cn>
Thanks for the patch! One comment below:
> diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
> index 6e826b454082..679dd3b5db70 100644
> --- a/fs/quota/dquot.c
> +++ b/fs/quota/dquot.c
> @@ -2983,13 +2983,9 @@ static int __init dquot_init(void)
>
> /* Find power-of-two hlist_heads which can fit into allocation */
> nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head);
> - dq_hash_bits = 0;
> - do {
> - dq_hash_bits++;
> - } while (nr_hash >> dq_hash_bits);
> - dq_hash_bits--;
> + nr_hash = rounddown_pow_of_two(nr_hash);
> + dq_hash_bits = ilog2(nr_hash);
>
> - nr_hash = 1UL << dq_hash_bits;
Why not just:
dq_hash_bits = ilog2(nr_hash);
nr_hash = 1UL << dq_hash_bits;
That way we need to compute fls() only once...
Honza
--
Jan Kara <j...@suse.com>
SUSE Labs, CR
