[PATCH] use find_trylock_page in free_swap_and_cache instead of hand coding

Use find_*_page helpers in swap code instead handcoding it.
Signed-off-by: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

mm/swap_state.c

@@ -315,13 +315,11 @@ struct page * lookup_swap_cache(swp_entry_t entry)
 {
 	struct page *page;
 
-	read_lock_irq(&swapper_space.tree_lock);
-	page = radix_tree_lookup(&swapper_space.page_tree, entry.val);
-	if (page) {
-		page_cache_get(page);
+	page = find_get_page(&swapper_space, entry.val);
+
+	if (page)
 		INC_CACHE_INFO(find_success);
-	}
-	read_unlock_irq(&swapper_space.tree_lock);
+
 	INC_CACHE_INFO(find_total);
 	return page;
 }
@@ -344,12 +342,7 @@ struct page *read_swap_cache_async(swp_entry_t entry,
 		 * called after lookup_swap_cache() failed, re-calling
 		 * that would confuse statistics.
 		 */
-		read_lock_irq(&swapper_space.tree_lock);
-		found_page = radix_tree_lookup(&swapper_space.page_tree,
-						entry.val);
-		if (found_page)
-			page_cache_get(found_page);
-		read_unlock_irq(&swapper_space.tree_lock);
+		found_page = find_get_page(&swapper_space, entry.val);
 		if (found_page)
 			break;
 

mm/swapfile.c

@@ -391,14 +391,8 @@ void free_swap_and_cache(swp_entry_t entry)
 
 	p = swap_info_get(entry);
 	if (p) {
-		if (swap_entry_free(p, swp_offset(entry)) == 1) {
-			read_lock_irq(&swapper_space.tree_lock);
-			page = radix_tree_lookup(&swapper_space.page_tree,
-				entry.val);
-			if (page && TestSetPageLocked(page))
-				page = NULL;
-			read_unlock_irq(&swapper_space.tree_lock);
-		}
+		if (swap_entry_free(p, swp_offset(entry)) == 1)
+			page = find_trylock_page(&swapper_space, entry.val);
 		swap_info_put(p);
 	}
 	if (page) {