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Date:   Tue, 11 Jul 2023 21:22:44 -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: [PATCH v2 6/8] maple_tree: update mt_validate()
Message-ID: <20230712012244.5o2cxqowoe5dmw7k@revolver>
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* Peng Zhang <zhangpeng.00@bytedance.com> [230710 23:55]:
> Instead of using mas_first_entry() to find the leftmost leaf, use a
> simple loop instead. Remove an unneeded check for root node. To make
> the error message more accurate, check pivots first and then slots,
> because checking slots depend on the node limit pivot to break the loop.
> 
> Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>

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

> ---
>  lib/maple_tree.c | 19 +++++++++----------
>  1 file changed, 9 insertions(+), 10 deletions(-)
> 
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index 072532fa18ee..1ad11799e197 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -7270,21 +7270,20 @@ void mt_validate(struct maple_tree *mt)
>  	if (!mas_searchable(&mas))
>  		goto done;
>  
> -	mas_first_entry(&mas, mas_mn(&mas), ULONG_MAX, mte_node_type(mas.node));
> +	while (!mte_is_leaf(mas.node))
> +		mas_descend(&mas);
> +
>  	while (!mas_is_none(&mas)) {
>  		MAS_WARN_ON(&mas, mte_dead_node(mas.node));
> -		if (!mte_is_root(mas.node)) {
> -			end = mas_data_end(&mas);
> -			if (MAS_WARN_ON(&mas,
> -					(end < mt_min_slot_count(mas.node)) &&
> -					(mas.max != ULONG_MAX))) {
> -				pr_err("Invalid size %u of %p\n", end,
> -				       mas_mn(&mas));
> -			}
> +		end = mas_data_end(&mas);
> +		if (MAS_WARN_ON(&mas, (end < mt_min_slot_count(mas.node)) &&
> +				(mas.max != ULONG_MAX))) {
> +			pr_err("Invalid size %u of %p\n", end, mas_mn(&mas));
>  		}
> +
>  		mas_validate_parent_slot(&mas);
> -		mas_validate_child_slot(&mas);
>  		mas_validate_limits(&mas);
> +		mas_validate_child_slot(&mas);
>  		if (mt_is_alloc(mt))
>  			mas_validate_gaps(&mas);
>  		mas_dfs_postorder(&mas, ULONG_MAX);
> -- 
> 2.20.1
> 
> 
> -- 
> maple-tree mailing list
> maple-tree@lists.infradead.org
> https://lists.infradead.org/mailman/listinfo/maple-tree