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Message-ID: <217a8c6b-a4d9-dba3-5a31-6f69414e0c46@bytedance.com>
Date:   Mon, 10 Jul 2023 17:47:27 +0800
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Subject: Re: [RESEND PATCH 6/8] maple_tree: update mt_validate()
To:     "Liam R. Howlett" <Liam.Howlett@Oracle.com>
References: <20230707101057.29326-1-zhangpeng.00@bytedance.com>
 <20230707101057.29326-7-zhangpeng.00@bytedance.com>
 <20230707150217.2ppiuemszsd5okfa@revolver>
Cc:     Peng Zhang <zhangpeng.00@bytedance.com>, akpm@linux-foundation.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        maple-tree@lists.infradead.org
From:   Peng Zhang <zhangpeng.00@bytedance.com>
In-Reply-To: <20230707150217.2ppiuemszsd5okfa@revolver>
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在 2023/7/7 23:02, Liam R. Howlett 写道:
> * Peng Zhang <zhangpeng.00@bytedance.com> [230707 06:11]:
>> 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>
>> ---
>>   lib/maple_tree.c | 21 +++++++++++----------
>>   1 file changed, 11 insertions(+), 10 deletions(-)
>>
>> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
>> index e84a042b6d84..3aede7deaa26 100644
>> --- a/lib/maple_tree.c
>> +++ b/lib/maple_tree.c
>> @@ -7260,21 +7260,22 @@ 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))) {
> 
> This line can be reformatted now that it is not as nested.
> 
>> +			pr_err("Invalid size %u of %p\n", end,
>> +				mas_mn(&mas));
> 
> Ditto here.
Thanks, I'll reformat it.
> 
>>   		}
>> +
>>   		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
>>
>>