diff --git a/Documentation/core-api/maple_tree.rst b/Documentation/core-api/maple_tree.rst
index 96f3d5f076b57cc525db8fe2fc7d380c1235175a..ccdd1615cf974f40ad2f655ca734b7bfcdb5ba94 100644
--- a/Documentation/core-api/maple_tree.rst
+++ b/Documentation/core-api/maple_tree.rst
@@ -81,6 +81,9 @@ section.
 Sometimes it is necessary to ensure the next call to store to a maple tree does
 not allocate memory, please see :ref:`maple-tree-advanced-api` for this use case.
 
+You can use mtree_dup() to duplicate an entire maple tree. It is a more
+efficient way than inserting all elements one by one into a new tree.
+
 Finally, you can remove all entries from a maple tree by calling
 mtree_destroy().  If the maple tree entries are pointers, you may wish to free
 the entries first.
@@ -112,6 +115,7 @@ Takes ma_lock internally:
  * mtree_insert()
  * mtree_insert_range()
  * mtree_erase()
+ * mtree_dup()
  * mtree_destroy()
  * mt_set_in_rcu()
  * mt_clear_in_rcu()