mm/sl[aou]b: Common alignment code

Extract the code to do object alignment from the allocators.
Do the alignment calculations in slab_common so that the
__kmem_cache_create functions of the allocators do not have
to deal with alignment.

Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

1 files changed, 1 insertions, 37 deletions

diff --git a/mm/slub.c b/mm/slub.c
index c82453ac812a..9640edd2cc78 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2760,32 +2760,6 @@ static inline int calculate_order(int size, int reserved)
         return -ENOSYS;
 }
 
-/*
- * Figure out what the alignment of the objects will be.
- */
-static unsigned long calculate_alignment(unsigned long flags,
-                unsigned long align, unsigned long size)
-{
-        /*
-         * If the user wants hardware cache aligned objects then follow that
-         * suggestion if the object is sufficiently large.
-         *
-         * The hardware cache alignment cannot override the specified
-         * alignment though. If that is greater then use it.
-         */
-        if (flags & SLAB_HWCACHE_ALIGN) {
-                unsigned long ralign = cache_line_size();
-                while (size <= ralign / 2)
-                        ralign /= 2;
-                align = max(align, ralign);
-        }
-
-        if (align < ARCH_SLAB_MINALIGN)
-                align = ARCH_SLAB_MINALIGN;
-
-        return ALIGN(align, sizeof(void *));
-}
-
 static void
 init_kmem_cache_node(struct kmem_cache_node *n)
 {
@@ -2919,7 +2893,6 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order)
 {
         unsigned long flags = s->flags;
         unsigned long size = s->object_size;
-        unsigned long align = s->align;
         int order;
 
         /*
@@ -2991,19 +2964,11 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order)
 #endif
 
         /*
-         * Determine the alignment based on various parameters that the
-         * user specified and the dynamic determination of cache line size
-         * on bootup.
-         */
-        align = calculate_alignment(flags, align, s->object_size);
-        s->align = align;
-
-        /*
          * SLUB stores one object immediately after another beginning from
          * offset 0. In order to align the objects we have to simply size
          * each object to conform to the alignment.
          */
-        size = ALIGN(size, align);
+        size = ALIGN(size, s->align);
         s->size = size;
         if (forced_order >= 0)
                 order = forced_order;
@@ -3032,7 +2997,6 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order)
                 s->max = s->oo;
 
         return !!oo_objects(s->oo);
-
 }
 
 static int kmem_cache_open(struct kmem_cache *s, unsigned long flags)