[PATCH] radix-tree: document wrap-around issue of radix_tree_next_hole()

Wu Fengguang
2008-11-23T10:51:55Z

And some 80-line cleanups.

Signed-off-by: Wu Fengguang <wfg@linux.intel.com>
---
lib/radix-tree.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

--- linux-2.6.orig/lib/radix-tree.c
+++ linux-2.6/lib/radix-tree.c
@@ -640,13 +640,14 @@ EXPORT_SYMBOL(radix_tree_tag_get);
*
* Returns: the index of the hole if found, otherwise returns an index
* outside of the set specified (in which case 'return - index >= max_scan'
- * will be true).
+ * will be true). In rare cases of index wrap-around, 0 will be returned.
*
* radix_tree_next_hole may be called under rcu_read_lock. However, like
- * radix_tree_gang_lookup, this will not atomically search a snapshot of the
- * tree at a single point in time. For example, if a hole is created at index
- * 5, then subsequently a hole is created at index 10, radix_tree_next_hole
- * covering both indexes may return 10 if called under rcu_read_lock.
+ * radix_tree_gang_lookup, this will not atomically search a snapshot of
+ * the tree at a single point in time. For example, if a hole is created
+ * at index 5, then subsequently a hole is created at index 10,
+ * radix_tree_next_hole covering both indexes may return 10 if called
+ * under rcu_read_lock.
*/
unsigned long radix_tree_next_hole(struct radix_tree_root *root,
unsigned long index, unsigned long max_scan)