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From:   Peng Zhang <zhangpeng.00@bytedance.com>
To:     Liam.Howlett@oracle.com
Cc:     akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, maple-tree@lists.infradead.org,
        Peng Zhang <zhangpeng.00@bytedance.com>
Subject: [PATCH 6/8] maple_tree: update mt_validate()
Date:   Thu, 15 Jun 2023 21:08:57 +0800
Message-Id: <20230615130859.21858-7-zhangpeng.00@bytedance.com>
In-Reply-To: <20230615130859.21858-1-zhangpeng.00@bytedance.com>
References: <20230615130859.21858-1-zhangpeng.00@bytedance.com>
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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 6c9b62e41605..becb4c224e57 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -7256,21 +7256,22 @@ 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))) {
+			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