mm: pagecache insertion fewer atomics
Setting and clearing the page locked when inserting it into swapcache /
pagecache when it has no other references can use non-atomic page flags
operations because no other CPU may be operating on it at this time.
This saves one atomic operation when inserting a page into pagecache.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 43cda7b..3353c90 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -303,7 +303,7 @@
* re-using the just freed swap entry for an existing page.
* May fail (-ENOMEM) if radix-tree node allocation failed.
*/
- set_page_locked(new_page);
+ __set_page_locked(new_page);
SetPageSwapBacked(new_page);
err = add_to_swap_cache(new_page, entry, gfp_mask & GFP_KERNEL);
if (likely(!err)) {
@@ -315,7 +315,7 @@
return new_page;
}
ClearPageSwapBacked(new_page);
- clear_page_locked(new_page);
+ __clear_page_locked(new_page);
swap_free(entry);
} while (err != -ENOMEM);