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Date:   Fri, 7 Jul 2023 11:19:08 -0400
From:   "Liam R. Howlett" <Liam.Howlett@Oracle.com>
To:     Peng Zhang <zhangpeng.00@bytedance.com>
Cc:     akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, maple-tree@lists.infradead.org
Subject: Re: [RESEND PATCH 7/8] maple_tree: replace mas_logical_pivot() with
 mas_safe_pivot()
Message-ID: <20230707151908.ypq3mlqqgyven2xa@revolver>
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References: <20230707101057.29326-1-zhangpeng.00@bytedance.com>
 <20230707101057.29326-8-zhangpeng.00@bytedance.com>
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* Peng Zhang <zhangpeng.00@bytedance.com> [230707 06:11]:
> Replace mas_logical_pivot() with mas_safe_pivot() and drop
> mas_logical_pivot() since it won't be used anymore. We can do this since
> now all nodes will have node limit pivot (if it is not full node).
> 
> Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>

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

> ---
>  lib/maple_tree.c | 33 +++------------------------------
>  1 file changed, 3 insertions(+), 30 deletions(-)
> 
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index 3aede7deaa26..8c08bfdc99cf 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -728,33 +728,6 @@ mas_safe_min(struct ma_state *mas, unsigned long *pivots, unsigned char offset)
>  	return mas->min;
>  }
>  
> -/*
> - * mas_logical_pivot() - Get the logical pivot of a given offset.
> - * @mas: The maple state
> - * @pivots: The pointer to the maple node pivots
> - * @offset: The offset into the pivot array
> - * @type: The maple node type
> - *
> - * When there is no value at a pivot (beyond the end of the data), then the
> - * pivot is actually @mas->max.
> - *
> - * Return: the logical pivot of a given @offset.
> - */
> -static inline unsigned long
> -mas_logical_pivot(struct ma_state *mas, unsigned long *pivots,
> -		  unsigned char offset, enum maple_type type)
> -{
> -	unsigned long lpiv = mas_safe_pivot(mas, pivots, offset, type);
> -
> -	if (likely(lpiv))
> -		return lpiv;
> -
> -	if (likely(offset))
> -		return mas->max;
> -
> -	return lpiv;
> -}
> -
>  /*
>   * mte_set_pivot() - Set a pivot to a value in an encoded maple node.
>   * @mn: The encoded maple node
> @@ -2202,7 +2175,7 @@ static noinline_for_kasan void mas_store_b_node(struct ma_wr_state *wr_mas,
>  		goto b_end;
>  
>  	/* Handle new range ending before old range ends */
> -	piv = mas_logical_pivot(mas, wr_mas->pivots, offset_end, wr_mas->type);
> +	piv = mas_safe_pivot(mas, wr_mas->pivots, offset_end, wr_mas->type);
>  	if (piv > mas->last) {
>  		if (piv == ULONG_MAX)
>  			mas_bulk_rebalance(mas, b_node->b_end, wr_mas->type);
> @@ -4934,7 +4907,7 @@ static inline bool mas_anode_descend(struct ma_state *mas, unsigned long size)
>  	min = mas_safe_min(mas, pivots, offset);
>  	data_end = ma_data_end(node, type, pivots, mas->max);
>  	for (; offset <= data_end; offset++) {
> -		pivot = mas_logical_pivot(mas, pivots, offset, type);
> +		pivot = mas_safe_pivot(mas, pivots, offset, type);
>  
>  		/* Not within lower bounds */
>  		if (mas->index > pivot)
> @@ -7007,7 +6980,7 @@ static void mas_validate_gaps(struct ma_state *mas)
>  
>  	gaps = ma_gaps(node, mt);
>  	for (i = 0; i < mt_slot_count(mte); i++) {
> -		p_end = mas_logical_pivot(mas, pivots, i, mt);
> +		p_end = mas_safe_pivot(mas, pivots, i, mt);
>  
>  		if (!gaps) {
>  			if (!mas_get_slot(mas, i))
> -- 
> 2.20.1
> 
>