[PATCH] mm: less atomic ops
In the page release paths, we can be sure that nobody will mess with our
page->flags because the refcount has dropped to 0. So no need for atomic
operations here.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h
index 8ac854f..3b6723d 100644
--- a/include/linux/mm_inline.h
+++ b/include/linux/mm_inline.h
@@ -32,7 +32,7 @@
{
list_del(&page->lru);
if (PageActive(page)) {
- ClearPageActive(page);
+ __ClearPageActive(page);
zone->nr_active--;
} else {
zone->nr_inactive--;
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 5d1e7bd..da71d63 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -242,10 +242,12 @@
#define PageLRU(page) test_bit(PG_lru, &(page)->flags)
#define SetPageLRU(page) set_bit(PG_lru, &(page)->flags)
#define ClearPageLRU(page) clear_bit(PG_lru, &(page)->flags)
+#define __ClearPageLRU(page) __clear_bit(PG_lru, &(page)->flags)
#define PageActive(page) test_bit(PG_active, &(page)->flags)
#define SetPageActive(page) set_bit(PG_active, &(page)->flags)
#define ClearPageActive(page) clear_bit(PG_active, &(page)->flags)
+#define __ClearPageActive(page) __clear_bit(PG_active, &(page)->flags)
#define PageSlab(page) test_bit(PG_slab, &(page)->flags)
#define SetPageSlab(page) set_bit(PG_slab, &(page)->flags)
diff --git a/mm/swap.c b/mm/swap.c
index cf88226..91b7e20 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -215,7 +215,7 @@
spin_lock_irqsave(&zone->lru_lock, flags);
BUG_ON(!PageLRU(page));
- ClearPageLRU(page);
+ __ClearPageLRU(page);
del_page_from_lru(zone, page);
spin_unlock_irqrestore(&zone->lru_lock, flags);
}
@@ -266,7 +266,7 @@
spin_lock_irq(&zone->lru_lock);
}
BUG_ON(!PageLRU(page));
- ClearPageLRU(page);
+ __ClearPageLRU(page);
del_page_from_lru(zone, page);
}
