SLUB: cleanup - define macros instead of hardcoded numbers
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
diff --git a/mm/slub.c b/mm/slub.c
index 7ad489a..7ec2888 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -153,6 +153,10 @@
#define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
#endif
+#define OO_SHIFT 16
+#define OO_MASK ((1 << OO_SHIFT) - 1)
+#define MAX_OBJS_PER_PAGE 65535 /* since page.objects is u16 */
+
/* Internal SLUB flags */
#define __OBJECT_POISON 0x80000000 /* Poison object */
#define __SYSFS_ADD_DEFERRED 0x40000000 /* Not yet visible via sysfs */
@@ -290,7 +294,7 @@
unsigned long size)
{
struct kmem_cache_order_objects x = {
- (order << 16) + (PAGE_SIZE << order) / size
+ (order << OO_SHIFT) + (PAGE_SIZE << order) / size
};
return x;
@@ -298,12 +302,12 @@
static inline int oo_order(struct kmem_cache_order_objects x)
{
- return x.x >> 16;
+ return x.x >> OO_SHIFT;
}
static inline int oo_objects(struct kmem_cache_order_objects x)
{
- return x.x & ((1 << 16) - 1);
+ return x.x & OO_MASK;
}
#ifdef CONFIG_SLUB_DEBUG
@@ -764,8 +768,8 @@
}
max_objects = (PAGE_SIZE << compound_order(page)) / s->size;
- if (max_objects > 65535)
- max_objects = 65535;
+ if (max_objects > MAX_OBJS_PER_PAGE)
+ max_objects = MAX_OBJS_PER_PAGE;
if (page->objects != max_objects) {
slab_err(s, page, "Wrong number of objects. Found %d but "
@@ -1807,8 +1811,8 @@
int rem;
int min_order = slub_min_order;
- if ((PAGE_SIZE << min_order) / size > 65535)
- return get_order(size * 65535) - 1;
+ if ((PAGE_SIZE << min_order) / size > MAX_OBJS_PER_PAGE)
+ return get_order(size * MAX_OBJS_PER_PAGE) - 1;
for (order = max(min_order,
fls(min_objects * size - 1) - PAGE_SHIFT);