radix tree: Remove radix_tree_update_node_t

The only user of this functionality was the workingset code, and it's
now been converted to the XArray.  Remove __radix_tree_delete_node()
entirely as it was also only used by the workingset code.

Signed-off-by: Matthew Wilcox <willy@infradead.org>

include/linux/radix-tree.h

@@ -242,17 +242,12 @@ void *__radix_tree_lookup(const struct radix_tree_root *, unsigned long index,
 void *radix_tree_lookup(const struct radix_tree_root *, unsigned long);
 void __rcu **radix_tree_lookup_slot(const struct radix_tree_root *,
 					unsigned long index);
-typedef void (*radix_tree_update_node_t)(struct radix_tree_node *);
 void __radix_tree_replace(struct radix_tree_root *, struct radix_tree_node *,
-			  void __rcu **slot, void *entry,
-			  radix_tree_update_node_t update_node);
+			  void __rcu **slot, void *entry);
 void radix_tree_iter_replace(struct radix_tree_root *,
 		const struct radix_tree_iter *, void __rcu **slot, void *entry);
 void radix_tree_replace_slot(struct radix_tree_root *,
 			     void __rcu **slot, void *entry);
-void __radix_tree_delete_node(struct radix_tree_root *,
-			      struct radix_tree_node *,
-			      radix_tree_update_node_t update_node);
 void radix_tree_iter_delete(struct radix_tree_root *,
 			struct radix_tree_iter *iter, void __rcu **slot);
 void *radix_tree_delete_item(struct radix_tree_root *, unsigned long, void *);

lib/idr.c

@@ -297,7 +297,7 @@ void *idr_replace(struct idr *idr, void *ptr, unsigned long id)
 	if (!slot || radix_tree_tag_get(&idr->idr_rt, id, IDR_FREE))
 		return ERR_PTR(-ENOENT);
 
-	__radix_tree_replace(&idr->idr_rt, node, slot, ptr, NULL);
+	__radix_tree_replace(&idr->idr_rt, node, slot, ptr);
 
 	return entry;
 }

lib/radix-tree.c

@@ -562,8 +562,7 @@ out:
  *	radix_tree_shrink    -    shrink radix tree to minimum height
  *	@root		radix tree root
  */
-static inline bool radix_tree_shrink(struct radix_tree_root *root,
-				     radix_tree_update_node_t update_node)
+static inline bool radix_tree_shrink(struct radix_tree_root *root)
 {
 	bool shrunk = false;
 
@@ -631,8 +630,6 @@ static inline bool radix_tree_shrink(struct radix_tree_root *root,
 		node->count = 0;
 		if (!radix_tree_is_internal_node(child)) {
 			node->slots[0] = (void __rcu *)RADIX_TREE_RETRY;
-			if (update_node)
-				update_node(node);
 		}
 
 		WARN_ON_ONCE(!list_empty(&node->private_list));
@@ -644,8 +641,7 @@ static inline bool radix_tree_shrink(struct radix_tree_root *root,
 }
 
 static bool delete_node(struct radix_tree_root *root,
-			struct radix_tree_node *node,
-			radix_tree_update_node_t update_node)
+			struct radix_tree_node *node)
 {
 	bool deleted = false;
 
@@ -655,7 +651,7 @@ static bool delete_node(struct radix_tree_root *root,
 		if (node->count) {
 			if (node_to_entry(node) ==
 					rcu_dereference_raw(root->xa_head))
-				deleted |= radix_tree_shrink(root, update_node);
+				deleted |= radix_tree_shrink(root);
 			return deleted;
 		}
 
@@ -1059,15 +1055,13 @@ static int calculate_count(struct radix_tree_root *root,
  * @node:		pointer to tree node
  * @slot:		pointer to slot in @node
  * @item:		new item to store in the slot.
- * @update_node:	callback for changing leaf nodes
  *
  * For use with __radix_tree_lookup().  Caller must hold tree write locked
  * across slot lookup and replacement.
  */
 void __radix_tree_replace(struct radix_tree_root *root,
 			  struct radix_tree_node *node,
-			  void __rcu **slot, void *item,
-			  radix_tree_update_node_t update_node)
+			  void __rcu **slot, void *item)
 {
 	void *old = rcu_dereference_raw(*slot);
 	int values = !!xa_is_value(item) - !!xa_is_value(old);
@@ -1085,10 +1079,7 @@ void __radix_tree_replace(struct radix_tree_root *root,
 	if (!node)
 		return;
 
-	if (update_node)
-		update_node(node);
-
-	delete_node(root, node, update_node);
+	delete_node(root, node);
 }
 
 /**
@@ -1110,7 +1101,7 @@ void __radix_tree_replace(struct radix_tree_root *root,
 void radix_tree_replace_slot(struct radix_tree_root *root,
 			     void __rcu **slot, void *item)
 {
-	__radix_tree_replace(root, NULL, slot, item, NULL);
+	__radix_tree_replace(root, NULL, slot, item);
 }
 EXPORT_SYMBOL(radix_tree_replace_slot);
 
@@ -1127,7 +1118,7 @@ void radix_tree_iter_replace(struct radix_tree_root *root,
 				const struct radix_tree_iter *iter,
 				void __rcu **slot, void *item)
 {
-	__radix_tree_replace(root, iter->node, slot, item, NULL);
+	__radix_tree_replace(root, iter->node, slot, item);
 }
 
 #ifdef CONFIG_RADIX_TREE_MULTIORDER
@@ -1807,23 +1798,6 @@ radix_tree_gang_lookup_tag_slot(const struct radix_tree_root *root,
 }
 EXPORT_SYMBOL(radix_tree_gang_lookup_tag_slot);
 
-/**
- *	__radix_tree_delete_node    -    try to free node after clearing a slot
- *	@root:		radix tree root
- *	@node:		node containing @index
- *	@update_node:	callback for changing leaf nodes
- *
- *	After clearing the slot at @index in @node from radix tree
- *	rooted at @root, call this function to attempt freeing the
- *	node and shrinking the tree.
- */
-void __radix_tree_delete_node(struct radix_tree_root *root,
-			      struct radix_tree_node *node,
-			      radix_tree_update_node_t update_node)
-{
-	delete_node(root, node, update_node);
-}
-
 static bool __radix_tree_delete(struct radix_tree_root *root,
 				struct radix_tree_node *node, void __rcu **slot)
 {
@@ -1839,7 +1813,7 @@ static bool __radix_tree_delete(struct radix_tree_root *root,
 			node_tag_clear(root, node, tag, offset);
 
 	replace_slot(slot, NULL, node, -1, values);
-	return node && delete_node(root, node, NULL);
+	return node && delete_node(root, node);
 }
 
 /**

tools/testing/radix-tree/multiorder.c

@@ -618,7 +618,7 @@ static void multiorder_account(void)
 	__radix_tree_insert(&tree, 1 << 5, 5, xa_mk_value(5));
 	__radix_tree_lookup(&tree, 1 << 5, &node, &slot);
 	assert(node->count == node->nr_values * 2);
-	__radix_tree_replace(&tree, node, slot, NULL, NULL);
+	__radix_tree_replace(&tree, node, slot, NULL);
 	assert(node->nr_values == 0);
 
 	item_kill_tree(&tree);