mm: remove useless rcu lock-unlock from mapping_tagged()
radix_tree_tagged() is lockless - it reads from a member of the raid-tree
root node. It does not require any protection.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 31f6988..919b45e 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1405,10 +1405,6 @@
*/
int mapping_tagged(struct address_space *mapping, int tag)
{
- int ret;
- rcu_read_lock();
- ret = radix_tree_tagged(&mapping->page_tree, tag);
- rcu_read_unlock();
- return ret;
+ return radix_tree_tagged(&mapping->page_tree, tag);
}
EXPORT_SYMBOL(mapping_tagged);