slab: Common Kmalloc cache determination

Extract the optimized lookup functions from slub and put them into
slab_common.c. Then make slab use these functions as well.

Joonsoo notes that this fixes some issues with constant folding which
also reduces the code size for slub.

https://lkml.org/lkml/2012/10/20/82

Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
This commit is contained in:
Christoph Lameter
2013-01-10 19:14:19 +00:00
committed by Pekka Enberg
parent 9e5e8deca7
commit 2c59dd6544
5 changed files with 124 additions and 173 deletions

View File

@ -656,40 +656,6 @@ static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep)
return cachep->array[smp_processor_id()];
}
static inline struct kmem_cache *__find_general_cachep(size_t size,
gfp_t gfpflags)
{
int i;
#if DEBUG
/* This happens if someone tries to call
* kmem_cache_create(), or __kmalloc(), before
* the generic caches are initialized.
*/
BUG_ON(kmalloc_caches[INDEX_AC] == NULL);
#endif
if (!size)
return ZERO_SIZE_PTR;
i = kmalloc_index(size);
/*
* Really subtle: The last entry with cs->cs_size==ULONG_MAX
* has cs_{dma,}cachep==NULL. Thus no special case
* for large kmalloc calls required.
*/
#ifdef CONFIG_ZONE_DMA
if (unlikely(gfpflags & GFP_DMA))
return kmalloc_dma_caches[i];
#endif
return kmalloc_caches[i];
}
static struct kmem_cache *kmem_find_general_cachep(size_t size, gfp_t gfpflags)
{
return __find_general_cachep(size, gfpflags);
}
static size_t slab_mgmt_size(size_t nr_objs, size_t align)
{
return ALIGN(sizeof(struct slab)+nr_objs*sizeof(kmem_bufctl_t), align);
@ -2426,7 +2392,7 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags)
cachep->reciprocal_buffer_size = reciprocal_value(size);
if (flags & CFLGS_OFF_SLAB) {
cachep->slabp_cache = kmem_find_general_cachep(slab_size, 0u);
cachep->slabp_cache = kmalloc_slab(slab_size, 0u);
/*
* This is a possibility for one of the malloc_sizes caches.
* But since we go off slab only for object size greater than
@ -3729,7 +3695,7 @@ __do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller)
{
struct kmem_cache *cachep;
cachep = kmem_find_general_cachep(size, flags);
cachep = kmalloc_slab(size, flags);
if (unlikely(ZERO_OR_NULL_PTR(cachep)))
return cachep;
return kmem_cache_alloc_node_trace(cachep, flags, node, size);
@ -3774,7 +3740,7 @@ static __always_inline void *__do_kmalloc(size_t size, gfp_t flags,
* Then kmalloc uses the uninlined functions instead of the inline
* functions.
*/
cachep = __find_general_cachep(size, flags);
cachep = kmalloc_slab(size, flags);
if (unlikely(ZERO_OR_NULL_PTR(cachep)))
return cachep;
ret = slab_alloc(cachep, flags, caller);