SLUB: this_cpu: Remove slub kmem_cache fields

Remove the fields in struct kmem_cache_cpu that were used to cache data from
struct kmem_cache when they were in different cachelines. The cacheline that
holds the per cpu array pointer now also holds these values. We can cut down
the struct kmem_cache_cpu size to almost half.

The get_freepointer() and set_freepointer() functions that used to be only
intended for the slow path now are also useful for the hot path since access
to the size field does not require accessing an additional cacheline anymore.
This results in consistent use of functions for setting the freepointer of
objects throughout SLUB.

Also we initialize all possible kmem_cache_cpu structures when a slab is
created. No need to initialize them when a processor or node comes online.

Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>

1 files changed, 0 insertions, 2 deletions

diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
index a78fb4ac2015..0249d4175bac 100644
--- a/include/linux/slub_def.h
+++ b/include/linux/slub_def.h
@@ -38,8 +38,6 @@ struct kmem_cache_cpu {
         void **freelist;        /* Pointer to first free per cpu object */
         struct page *page;      /* The slab from which we are allocating */
         int node;               /* The node of the page (or -1 for debug) */
-        unsigned int offset;    /* Freepointer offset (in word units) */
-        unsigned int objsize;   /* Size of an object (from kmem_cache) */
 #ifdef CONFIG_SLUB_STATS
         unsigned stat[NR_SLUB_STAT_ITEMS];
 #endif