From 72c4783210f77fd743f0a316858d33f27db51e7c Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Mon, 25 Jul 2011 17:12:31 -0700 Subject: [PATCH] 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 Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/page-writeback.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 31f698862420..919b45eb57ad 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -1405,10 +1405,6 @@ EXPORT_SYMBOL(test_set_page_writeback); */ 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); -- 2.39.5