diff --git a/fs/buffer.c b/fs/buffer.c
index 517860f..865570f 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -724,20 +724,19 @@
 	}
 	spin_unlock(&mapping->private_lock);
 
-	if (!TestSetPageDirty(page)) {
-		write_lock_irq(&mapping->tree_lock);
-		if (page->mapping) {	/* Race with truncate? */
-			if (mapping_cap_account_dirty(mapping))
-				__inc_zone_page_state(page, NR_FILE_DIRTY);
-			radix_tree_tag_set(&mapping->page_tree,
-						page_index(page),
-						PAGECACHE_TAG_DIRTY);
-		}
-		write_unlock_irq(&mapping->tree_lock);
-		__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
-		return 1;
+	if (TestSetPageDirty(page))
+		return 0;
+
+	write_lock_irq(&mapping->tree_lock);
+	if (page->mapping) {	/* Race with truncate? */
+		if (mapping_cap_account_dirty(mapping))
+			__inc_zone_page_state(page, NR_FILE_DIRTY);
+		radix_tree_tag_set(&mapping->page_tree,
+				page_index(page), PAGECACHE_TAG_DIRTY);
 	}
-	return 0;
+	write_unlock_irq(&mapping->tree_lock);
+	__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
+	return 1;
 }
 EXPORT_SYMBOL(__set_page_dirty_buffers);