Re: [PATCH 2/2] maple_tree: goto complete directly on a pivot of 0

["Liam R. Howlett" <Liam.Howlett@oracle.com>]

* Wei Yang <richard.weiyang@gmail.com> [240911 10:29]:
> When we break the loop after assigning a pivot, the index i/j is not
> changed. Then the following code assign pivot, which means we do the
> assignment with same i/j by mas_safe_pivot.
> 
> Since the loop condition is (i < piv_end), from which we can get i is
> less than mt_pivots[mt]. It implies mas_safe_pivot() return pivot[i]
> which is the same value we get in loop.
> 
> Now we can conclude it does a redundant assignment on a pivot of 0.
> Let's just go to complete to avoid it.
> 
> Signed-off-by: Wei Yang <richard.weiyang@gmail.com>

Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>

> ---
>  lib/maple_tree.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index 6fd62b7ef240..f7bb3f686548 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -1942,7 +1942,7 @@ static inline void mas_mab_cp(struct ma_state *mas, unsigned char mas_start,
>  	for (; i < piv_end; i++, j++) {
>  		b_node->pivot[j] = pivots[i];
>  		if (unlikely(!b_node->pivot[j]))
> -			break;
> +			goto complete;
>  
>  		if (unlikely(mas->max == b_node->pivot[j]))
>  			goto complete;
> -- 
> 2.34.1
>