[PATCH v2 6/8] maple_tree: update mt_validate()

[Peng Zhang <zhangpeng.00@xxxxxxxxxxxxx>]

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@xxxxxxxxxxxxx>
---
 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