Date:   Fri, 10 Mar 2023 14:20:04 -0500
From:   "Liam R. Howlett" <Liam.Howlett@Oracle.com>
To:     Peng Zhang <zhangpeng.00@bytedance.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        maple-tree@lists.infradead.org
Subject: Re: [PATCH 2/4] maple_tree: Simplify mas_wr_node_walk()
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* Peng Zhang <zhangpeng.00@bytedance.com> [230310 09:09]:
> Simplify code of mas_wr_node_walk() without changing functionality,
> and improve readability.

The change log needs to be updated to 

I like this change, thanks.

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

> 
> Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>
> ---
>  lib/maple_tree.c | 34 +++++-----------------------------
>  1 file changed, 5 insertions(+), 29 deletions(-)
> 
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index b3164266cfde..4d15202a0692 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -2251,9 +2251,7 @@ static inline struct maple_enode *mte_node_or_none(struct maple_enode *enode)
>  static inline void mas_wr_node_walk(struct ma_wr_state *wr_mas)
>  {
>  	struct ma_state *mas = wr_mas->mas;
> -	unsigned char count;
> -	unsigned char offset;
> -	unsigned long index, min, max;
> +	unsigned char count, offset;
>  
>  	if (unlikely(ma_is_dense(wr_mas->type))) {
>  		wr_mas->r_max = wr_mas->r_min = mas->index;
> @@ -2266,34 +2264,12 @@ static inline void mas_wr_node_walk(struct ma_wr_state *wr_mas)
>  	count = wr_mas->node_end = ma_data_end(wr_mas->node, wr_mas->type,
>  					       wr_mas->pivots, mas->max);
>  	offset = mas->offset;
> -	min = mas_safe_min(mas, wr_mas->pivots, offset);
> -	if (unlikely(offset == count))
> -		goto max;
> -
> -	max = wr_mas->pivots[offset];
> -	index = mas->index;
> -	if (unlikely(index <= max))
> -		goto done;
> -
> -	if (unlikely(!max && offset))
> -		goto max;
>  
> -	min = max + 1;
> -	while (++offset < count) {
> -		max = wr_mas->pivots[offset];
> -		if (index <= max)
> -			goto done;
> -		else if (unlikely(!max))
> -			break;
> -
> -		min = max + 1;
> -	}
> +	while (offset < count && mas->index > wr_mas->pivots[offset])
> +		offset++;
>  
> -max:
> -	max = mas->max;
> -done:
> -	wr_mas->r_max = max;
> -	wr_mas->r_min = min;
> +	wr_mas->r_max = offset < count ? wr_mas->pivots[offset] : mas->max;
> +	wr_mas->r_min = mas_safe_min(mas, wr_mas->pivots, offset);
>  	wr_mas->offset_end = mas->offset = offset;
>  }
>  
> -- 
> 2.20.1
>