diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index 48c250fe2233..65f0e758ec38 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -95,14 +95,17 @@ static inline gfp_t root_gfp_mask(struct radix_tree_root *root)
 static struct radix_tree_node *
 radix_tree_node_alloc(struct radix_tree_root *root)
 {
-	struct radix_tree_node *ret;
+	struct radix_tree_node *ret = NULL;
 	gfp_t gfp_mask = root_gfp_mask(root);
 
-	ret = kmem_cache_alloc(radix_tree_node_cachep,
-				set_migrateflags(gfp_mask, __GFP_RECLAIMABLE));
-	if (ret == NULL && !(gfp_mask & __GFP_WAIT)) {
+	if (!(gfp_mask & __GFP_WAIT)) {
 		struct radix_tree_preload *rtp;
 
+		/*
+		 * Provided the caller has preloaded here, we will always
+		 * succeed in getting a node here (and never reach
+		 * kmem_cache_alloc)
+		 */
 		rtp = &__get_cpu_var(radix_tree_preloads);
 		if (rtp->nr) {
 			ret = rtp->nodes[rtp->nr - 1];
@@ -110,6 +113,10 @@ radix_tree_node_alloc(struct radix_tree_root *root)
 			rtp->nr--;
 		}
 	}
+	if (ret == NULL)
+		ret = kmem_cache_alloc(radix_tree_node_cachep,
+				set_migrateflags(gfp_mask, __GFP_RECLAIMABLE));
+
 	BUG_ON(radix_tree_is_indirect_ptr(ret));
 	return ret;
 }
diff --git a/mm/filemap.c b/mm/filemap.c
index 76bea88cbebc..96920f840562 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -65,7 +65,6 @@ generic_file_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
  *    ->private_lock		(__free_pte->__set_page_dirty_buffers)
  *      ->swap_lock		(exclusive_swap_page, others)
  *        ->mapping->tree_lock
- *          ->zone.lock
  *
  *  ->i_mutex
  *    ->i_mmap_lock		(truncate->unmap_mapping_range)
diff --git a/mm/rmap.c b/mm/rmap.c
index dbc2ca2057a5..0334c8f6b741 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -36,7 +36,6 @@
  *                 mapping->tree_lock (widely used, in set_page_dirty,
  *                           in arch-dependent flush_dcache_mmap_lock,
  *                           within inode_lock in __sync_single_inode)
- *                   zone->lock (within radix tree node alloc)
  */
 
 #include <linux/mm.h>