mm: rename page trylock

Converting page lock to new locking bitops requires a change of page flag
operation naming, so we might as well convert it to something nicer
(!TestSetPageLocked_Lock => trylock_page, SetPageLocked => set_page_locked).

This also facilitates lockdeping of page lock.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 75be453..1ff1a58 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -496,7 +496,7 @@
 		page = lru_to_page(page_list);
 		list_del(&page->lru);
 
-		if (TestSetPageLocked(page))
+		if (!trylock_page(page))
 			goto keep;
 
 		VM_BUG_ON(PageActive(page));
@@ -582,7 +582,7 @@
 				 * A synchronous write - probably a ramdisk.  Go
 				 * ahead and try to reclaim the page.
 				 */
-				if (TestSetPageLocked(page))
+				if (!trylock_page(page))
 					goto keep;
 				if (PageDirty(page) || PageWriteback(page))
 					goto keep_locked;