[net-next-2.6.git] / include / linux / slub_def.h

#ifndef _LINUX_SLUB_DEF_H
#define _LINUX_SLUB_DEF_H

/*
 * SLUB : A Slab allocator without object queues.
 *
 * (C) 2007 SGI, Christoph Lameter <clameter@sgi.com>
 */
#include <linux/types.h>
#include <linux/gfp.h>
#include <linux/workqueue.h>
#include <linux/kobject.h>

struct kmem_cache_node {
	spinlock_t list_lock;	/* Protect partial list and nr_partial */
	unsigned long nr_partial;
	atomic_long_t nr_slabs;
	struct list_head partial;
	struct list_head full;
};

/*
 * Slab cache management.
 */
struct kmem_cache {
	/* Used for retriving partial slabs etc */
	unsigned long flags;
	int size;		/* The size of an object including meta data */
	int objsize;		/* The size of an object without meta data */
	int offset;		/* Free pointer offset. */
	unsigned int order;

	/*
	 * Avoid an extra cache line for UP, SMP and for the node local to
	 * struct kmem_cache.
	 */
	struct kmem_cache_node local_node;

	/* Allocation and freeing of slabs */
	int objects;		/* Number of objects in slab */
	int refcount;		/* Refcount for slab cache destroy */
	void (*ctor)(void *, struct kmem_cache *, unsigned long);
	int inuse;		/* Offset to metadata */
	int align;		/* Alignment */
	const char *name;	/* Name (only for display!) */
	struct list_head list;	/* List of slab caches */
	struct kobject kobj;	/* For sysfs */

#ifdef CONFIG_NUMA
	int defrag_ratio;
	struct kmem_cache_node *node[MAX_NUMNODES];
#endif
	struct page *cpu_slab[NR_CPUS];
};

/*
 * Kmalloc subsystem.
 */
#define KMALLOC_SHIFT_LOW 3

/*
 * We keep the general caches in an array of slab caches that are used for
 * 2^x bytes of allocations.
 */
extern struct kmem_cache kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];

/*
 * Sorry that the following has to be that ugly but some versions of GCC
 * have trouble with constant propagation and loops.
 */
static inline int kmalloc_index(size_t size)
{
	if (!size)
		return 0;

	if (size > KMALLOC_MAX_SIZE)
		return -1;

	if (size > 64 && size <= 96)
		return 1;
	if (size > 128 && size <= 192)
		return 2;
	if (size <=          8) return 3;
	if (size <=         16) return 4;
	if (size <=         32) return 5;
	if (size <=         64) return 6;
	if (size <=        128) return 7;
	if (size <=        256) return 8;
	if (size <=        512) return 9;
	if (size <=       1024) return 10;
	if (size <=   2 * 1024) return 11;
	if (size <=   4 * 1024) return 12;
	if (size <=   8 * 1024) return 13;
	if (size <=  16 * 1024) return 14;
	if (size <=  32 * 1024) return 15;
	if (size <=  64 * 1024) return 16;
	if (size <= 128 * 1024) return 17;
	if (size <= 256 * 1024) return 18;
	if (size <=  512 * 1024) return 19;
	if (size <= 1024 * 1024) return 20;
	if (size <=  2 * 1024 * 1024) return 21;
	if (size <=  4 * 1024 * 1024) return 22;
	if (size <=  8 * 1024 * 1024) return 23;
	if (size <= 16 * 1024 * 1024) return 24;
	if (size <= 32 * 1024 * 1024) return 25;
	return -1;

/*
 * What we really wanted to do and cannot do because of compiler issues is:
 *	int i;
 *	for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
 *		if (size <= (1 << i))
 *			return i;
 */
}

/*
 * Find the slab cache for a given combination of allocation flags and size.
 *
 * This ought to end up with a global pointer to the right cache
 * in kmalloc_caches.
 */
static inline struct kmem_cache *kmalloc_slab(size_t size)
{
	int index = kmalloc_index(size);

	if (index == 0)
		return NULL;

	/*
	 * This function only gets expanded if __builtin_constant_p(size), so
	 * testing it here shouldn't be needed.  But some versions of gcc need
	 * help.
	 */
	if (__builtin_constant_p(size) && index < 0) {
		/*
		 * Generate a link failure. Would be great if we could
		 * do something to stop the compile here.
		 */
		extern void __kmalloc_size_too_large(void);
		__kmalloc_size_too_large();
	}
	return &kmalloc_caches[index];
}

#ifdef CONFIG_ZONE_DMA
#define SLUB_DMA __GFP_DMA
#else
/* Disable DMA functionality */
#define SLUB_DMA 0
#endif


/*
 * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
 *
 * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
 *
 * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
 * Both make kfree a no-op.
 */
#define ZERO_SIZE_PTR ((void *)16)


static inline void *kmalloc(size_t size, gfp_t flags)
{
	if (__builtin_constant_p(size) && !(flags & SLUB_DMA)) {
		struct kmem_cache *s = kmalloc_slab(size);

		if (!s)
			return ZERO_SIZE_PTR;

		return kmem_cache_alloc(s, flags);
	} else
		return __kmalloc(size, flags);
}

static inline void *kzalloc(size_t size, gfp_t flags)
{
	if (__builtin_constant_p(size) && !(flags & SLUB_DMA)) {
		struct kmem_cache *s = kmalloc_slab(size);

		if (!s)
			return ZERO_SIZE_PTR;

		return kmem_cache_zalloc(s, flags);
	} else
		return __kzalloc(size, flags);
}

#ifdef CONFIG_NUMA
extern void *__kmalloc_node(size_t size, gfp_t flags, int node);

static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
{
	if (__builtin_constant_p(size) && !(flags & SLUB_DMA)) {
		struct kmem_cache *s = kmalloc_slab(size);

		if (!s)
			return ZERO_SIZE_PTR;

		return kmem_cache_alloc_node(s, flags, node);
	} else
		return __kmalloc_node(size, flags, node);
}
#endif

#endif /* _LINUX_SLUB_DEF_H */
Commit	Line	Data
81819f0f CL	1	#ifndef _LINUX_SLUB_DEF_H
	2	#define _LINUX_SLUB_DEF_H
	3
	4	/*
	5	* SLUB : A Slab allocator without object queues.
	6	*
	7	* (C) 2007 SGI, Christoph Lameter <clameter@sgi.com>
	8	*/
	9	#include <linux/types.h>
	10	#include <linux/gfp.h>
	11	#include <linux/workqueue.h>
	12	#include <linux/kobject.h>
	13
	14	struct kmem_cache_node {
	15	spinlock_t list_lock; /* Protect partial list and nr_partial */
	16	unsigned long nr_partial;
	17	atomic_long_t nr_slabs;
	18	struct list_head partial;
643b1138	19	struct list_head full;
81819f0f CL	20	};
	21
	22	/*
	23	* Slab cache management.
	24	*/
	25	struct kmem_cache {
	26	/* Used for retriving partial slabs etc */
	27	unsigned long flags;
	28	int size; /* The size of an object including meta data */
	29	int objsize; /* The size of an object without meta data */
	30	int offset; /* Free pointer offset. */
	31	unsigned int order;
	32
	33	/*
	34	* Avoid an extra cache line for UP, SMP and for the node local to
	35	* struct kmem_cache.
	36	*/
	37	struct kmem_cache_node local_node;
	38
	39	/* Allocation and freeing of slabs */
	40	int objects; /* Number of objects in slab */
	41	int refcount; /* Refcount for slab cache destroy */
	42	void (ctor)(void , struct kmem_cache *, unsigned long);
81819f0f CL	43	int inuse; /* Offset to metadata */
	44	int align; /* Alignment */
	45	const char name; / Name (only for display!) */
	46	struct list_head list; /* List of slab caches */
	47	struct kobject kobj; /* For sysfs */
	48
	49	#ifdef CONFIG_NUMA
	50	int defrag_ratio;
	51	struct kmem_cache_node *node[MAX_NUMNODES];
	52	#endif
	53	struct page *cpu_slab[NR_CPUS];
	54	};
	55
	56	/*
	57	* Kmalloc subsystem.
	58	*/
	59	#define KMALLOC_SHIFT_LOW 3
	60
81819f0f CL	61	/*
	62	* We keep the general caches in an array of slab caches that are used for
	63	* 2^x bytes of allocations.
	64	*/
	65	extern struct kmem_cache kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
	66
	67	/*
	68	* Sorry that the following has to be that ugly but some versions of GCC
	69	* have trouble with constant propagation and loops.
	70	*/
0aa817f0	71	static inline int kmalloc_index(size_t size)
81819f0f	72	{
272c1d21 CL	73	if (!size)
272c1d21 CL	74	return 0;
614410d5	75
0aa817f0	76	if (size > KMALLOC_MAX_SIZE)
cfbf07f2 CL	77	return -1;
cfbf07f2 CL	78
81819f0f CL	79	if (size > 64 && size <= 96)
	80	return 1;
	81	if (size > 128 && size <= 192)
	82	return 2;
	83	if (size <= 8) return 3;
	84	if (size <= 16) return 4;
	85	if (size <= 32) return 5;
	86	if (size <= 64) return 6;
	87	if (size <= 128) return 7;
	88	if (size <= 256) return 8;
	89	if (size <= 512) return 9;
	90	if (size <= 1024) return 10;
	91	if (size <= 2 * 1024) return 11;
	92	if (size <= 4 * 1024) return 12;
	93	if (size <= 8 * 1024) return 13;
	94	if (size <= 16 * 1024) return 14;
	95	if (size <= 32 * 1024) return 15;
	96	if (size <= 64 * 1024) return 16;
	97	if (size <= 128 * 1024) return 17;
	98	if (size <= 256 * 1024) return 18;
81819f0f CL	99	if (size <= 512 * 1024) return 19;
81819f0f CL	100	if (size <= 1024 * 1024) return 20;
81819f0f CL	101	if (size <= 2 * 1024 * 1024) return 21;
	102	if (size <= 4 * 1024 * 1024) return 22;
	103	if (size <= 8 * 1024 * 1024) return 23;
	104	if (size <= 16 * 1024 * 1024) return 24;
	105	if (size <= 32 * 1024 * 1024) return 25;
81819f0f CL	106	return -1;
	107
	108	/*
	109	* What we really wanted to do and cannot do because of compiler issues is:
	110	* int i;
	111	* for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
	112	* if (size <= (1 << i))
	113	* return i;
	114	*/
	115	}
	116
	117	/*
	118	* Find the slab cache for a given combination of allocation flags and size.
	119	*
	120	* This ought to end up with a global pointer to the right cache
	121	* in kmalloc_caches.
	122	*/
	123	static inline struct kmem_cache *kmalloc_slab(size_t size)
	124	{
	125	int index = kmalloc_index(size);
	126
	127	if (index == 0)
	128	return NULL;
	129
ade3aff2 AM	130	/*
	131	* This function only gets expanded if __builtin_constant_p(size), so
	132	* testing it here shouldn't be needed. But some versions of gcc need
	133	* help.
	134	*/
	135	if (__builtin_constant_p(size) && index < 0) {
81819f0f CL	136	/*
	137	* Generate a link failure. Would be great if we could
	138	* do something to stop the compile here.
	139	*/
	140	extern void __kmalloc_size_too_large(void);
	141	__kmalloc_size_too_large();
	142	}
	143	return &kmalloc_caches[index];
	144	}
	145
	146	#ifdef CONFIG_ZONE_DMA
	147	#define SLUB_DMA __GFP_DMA
	148	#else
	149	/* Disable DMA functionality */
	150	#define SLUB_DMA 0
	151	#endif
	152
272c1d21 CL	153
	154	/*
	155	* ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
	156	*
	157	* Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
	158	*
	159	* ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
	160	* Both make kfree a no-op.
	161	*/
	162	#define ZERO_SIZE_PTR ((void *)16)
	163
	164
81819f0f CL	165	static inline void *kmalloc(size_t size, gfp_t flags)
	166	{
	167	if (__builtin_constant_p(size) && !(flags & SLUB_DMA)) {
	168	struct kmem_cache *s = kmalloc_slab(size);
	169
	170	if (!s)
272c1d21	171	return ZERO_SIZE_PTR;
81819f0f CL	172
	173	return kmem_cache_alloc(s, flags);
	174	} else
	175	return __kmalloc(size, flags);
	176	}
	177
	178	static inline void *kzalloc(size_t size, gfp_t flags)
	179	{
	180	if (__builtin_constant_p(size) && !(flags & SLUB_DMA)) {
	181	struct kmem_cache *s = kmalloc_slab(size);
	182
	183	if (!s)
272c1d21	184	return ZERO_SIZE_PTR;
81819f0f CL	185
	186	return kmem_cache_zalloc(s, flags);
	187	} else
	188	return __kzalloc(size, flags);
	189	}
	190
	191	#ifdef CONFIG_NUMA
	192	extern void *__kmalloc_node(size_t size, gfp_t flags, int node);
	193
	194	static inline void *kmalloc_node(size_t size, gfp_t flags, int node)
	195	{
	196	if (__builtin_constant_p(size) && !(flags & SLUB_DMA)) {
	197	struct kmem_cache *s = kmalloc_slab(size);
	198
	199	if (!s)
272c1d21	200	return ZERO_SIZE_PTR;
81819f0f CL	201
	202	return kmem_cache_alloc_node(s, flags, node);
	203	} else
	204	return __kmalloc_node(size, flags, node);
	205	}
	206	#endif
	207
	208	#endif /* _LINUX_SLUB_DEF_H */