diff options
Diffstat (limited to 'include/linux/slab.h')
| -rw-r--r-- | include/linux/slab.h | 34 |
1 files changed, 24 insertions, 10 deletions
diff --git a/include/linux/slab.h b/include/linux/slab.h index c97fe92532d1..c01780540054 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -163,7 +163,12 @@ struct kmem_cache { #else /* CONFIG_SLOB */ /* - * The largest kmalloc size supported by the slab allocators is + * Kmalloc array related definitions + */ + +#ifdef CONFIG_SLAB +/* + * The largest kmalloc size supported by the SLAB allocators is * 32 megabyte (2^25) or the maximum allocatable page order if that is * less than 32 MB. * @@ -173,9 +178,24 @@ struct kmem_cache { */ #define KMALLOC_SHIFT_HIGH ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \ (MAX_ORDER + PAGE_SHIFT - 1) : 25) +#define KMALLOC_SHIFT_MAX KMALLOC_SHIFT_HIGH +#define KMALLOC_SHIFT_LOW 5 +#else +/* + * SLUB allocates up to order 2 pages directly and otherwise + * passes the request to the page allocator. + */ +#define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) +#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT) +#define KMALLOC_SHIFT_LOW 3 +#endif -#define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_HIGH) -#define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_HIGH - PAGE_SHIFT) +/* Maximum allocatable size */ +#define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX) +/* Maximum size for which we actually use a slab cache */ +#define KMALLOC_MAX_CACHE_SIZE (1UL << KMALLOC_SHIFT_HIGH) +/* Maximum order allocatable via the slab allocagtor */ +#define KMALLOC_MAX_ORDER (KMALLOC_SHIFT_MAX - PAGE_SHIFT) /* * Kmalloc subsystem. @@ -183,15 +203,9 @@ struct kmem_cache { #if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8 #define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN #else -#ifdef CONFIG_SLAB -#define KMALLOC_MIN_SIZE 32 -#else -#define KMALLOC_MIN_SIZE 8 -#endif +#define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW) #endif -#define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE) - /* * Figure out which kmalloc slab an allocation of a certain size * belongs to. |