SLUB: Do our own flags based on PG_active and PG_error
The atomicity when handling flags in SLUB is not necessary since both flags
used by SLUB are not updated in a racy way. Flag updates are either done
during slab creation or destruction or under slab_lock. Some of these flags
do not have the non atomic variants that we need. So define our own.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/slub.c b/mm/slub.c
index ce96d48..3ca164f 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -99,42 +99,42 @@
* the fast path and disables lockless freelists.
*/
+#define FROZEN (1 << PG_active)
+
+#ifdef CONFIG_SLUB_DEBUG
+#define SLABDEBUG (1 << PG_error)
+#else
+#define SLABDEBUG 0
+#endif
+
static inline int SlabFrozen(struct page *page)
{
- return PageActive(page);
+ return page->flags & FROZEN;
}
static inline void SetSlabFrozen(struct page *page)
{
- SetPageActive(page);
+ page->flags |= FROZEN;
}
static inline void ClearSlabFrozen(struct page *page)
{
- ClearPageActive(page);
+ page->flags &= ~FROZEN;
}
static inline int SlabDebug(struct page *page)
{
-#ifdef CONFIG_SLUB_DEBUG
- return PageError(page);
-#else
- return 0;
-#endif
+ return page->flags & SLABDEBUG;
}
static inline void SetSlabDebug(struct page *page)
{
-#ifdef CONFIG_SLUB_DEBUG
- SetPageError(page);
-#endif
+ page->flags |= SLABDEBUG;
}
static inline void ClearSlabDebug(struct page *page)
{
-#ifdef CONFIG_SLUB_DEBUG
- ClearPageError(page);
-#endif
+ page->flags &= ~SLABDEBUG;
}
/*