[deliverable/linux.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
 */
#include <linux/types.h>
#include <linux/gfp.h>
#include <linux/workqueue.h>
#include <linux/kobject.h>

enum stat_item {
	ALLOC_FASTPATH,		/* Allocation from cpu slab */
	ALLOC_SLOWPATH,		/* Allocation by getting a new cpu slab */
	FREE_FASTPATH,		/* Free to cpu slub */
	FREE_SLOWPATH,		/* Freeing not to cpu slab */
	FREE_FROZEN,		/* Freeing to frozen slab */
	FREE_ADD_PARTIAL,	/* Freeing moves slab to partial list */
	FREE_REMOVE_PARTIAL,	/* Freeing removes last object */
	ALLOC_FROM_PARTIAL,	/* Cpu slab acquired from partial list */
	ALLOC_SLAB,		/* Cpu slab acquired from page allocator */
	ALLOC_REFILL,		/* Refill cpu slab from slab freelist */
	FREE_SLAB,		/* Slab freed to the page allocator */
	CPUSLAB_FLUSH,		/* Abandoning of the cpu slab */
	DEACTIVATE_FULL,	/* Cpu slab was full when deactivated */
	DEACTIVATE_EMPTY,	/* Cpu slab was empty when deactivated */
	DEACTIVATE_TO_HEAD,	/* Cpu slab was moved to the head of partials */
	DEACTIVATE_TO_TAIL,	/* Cpu slab was moved to the tail of partials */
	DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */
	ORDER_FALLBACK,		/* Number of times fallback was necessary */
	NR_SLUB_STAT_ITEMS };

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
};

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

/*
 * Word size structure that can be atomically updated or read and that
 * contains both the order and the number of objects that a slab of the
 * given order would contain.
 */
struct kmem_cache_order_objects {
	unsigned long x;
};

/*
 * 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. */
	struct kmem_cache_order_objects oo;

	/*
	 * 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 */
	struct kmem_cache_order_objects max;
	struct kmem_cache_order_objects min;
	gfp_t allocflags;	/* gfp flags to use on each alloc */
	int refcount;		/* Refcount for slab cache destroy */
	void (*ctor)(struct kmem_cache *, void *);
	int inuse;		/* Offset to metadata */
	int align;		/* Alignment */
	const char *name;	/* Name (only for display!) */
	struct list_head list;	/* List of slab caches */
#ifdef CONFIG_SLUB_DEBUG
	struct kobject kobj;	/* For sysfs */
#endif

#ifdef CONFIG_NUMA
	/*
	 * Defragmentation by allocating from a remote node.
	 */
	int remote_node_defrag_ratio;
	struct kmem_cache_node *node[MAX_NUMNODES];
#endif
#ifdef CONFIG_SMP
	struct kmem_cache_cpu *cpu_slab[NR_CPUS];
#else
	struct kmem_cache_cpu cpu_slab;
#endif
};

/*
 * Kmalloc subsystem.
 */
#if defined(ARCH_KMALLOC_MINALIGN) && ARCH_KMALLOC_MINALIGN > 8
#define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN
#else
#define KMALLOC_MIN_SIZE 8
#endif

#define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)

/*
 * 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[PAGE_SHIFT + 1];

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

	if (size <= KMALLOC_MIN_SIZE)
		return KMALLOC_SHIFT_LOW;

#if KMALLOC_MIN_SIZE <= 64
	if (size > 64 && size <= 96)
		return 1;
	if (size > 128 && size <= 192)
		return 2;
#endif
	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;
/*
 * The following is only needed to support architectures with a larger page
 * size than 4k.
 */
	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;
	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 __always_inline struct kmem_cache *kmalloc_slab(size_t size)
{
	int index = kmalloc_index(size);

	if (index == 0)
		return NULL;

	return &kmalloc_caches[index];
}

#ifdef CONFIG_ZONE_DMA
#define SLUB_DMA __GFP_DMA
#else
/* Disable DMA functionality */
#define SLUB_DMA (__force gfp_t)0
#endif

void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
void *__kmalloc(size_t size, gfp_t flags);

static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
{
	return (void *)__get_free_pages(flags | __GFP_COMP, get_order(size));
}

static __always_inline void *kmalloc(size_t size, gfp_t flags)
{
	if (__builtin_constant_p(size)) {
		if (size > PAGE_SIZE)
			return kmalloc_large(size, flags);

		if (!(flags & SLUB_DMA)) {
			struct kmem_cache *s = kmalloc_slab(size);

			if (!s)
				return ZERO_SIZE_PTR;

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

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

static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
{
	if (__builtin_constant_p(size) &&
		size <= PAGE_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);
	}
	return __kmalloc_node(size, flags, node);
}
#endif

#endif /* _LINUX_SLUB_DEF_H */
Commit	Line	Data
	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
	8	*/
	9	#include <linux/types.h>
	10	#include <linux/gfp.h>
	11	#include <linux/workqueue.h>
	12	#include <linux/kobject.h>
	13
	14	enum stat_item {
	15	ALLOC_FASTPATH, /* Allocation from cpu slab */
	16	ALLOC_SLOWPATH, /* Allocation by getting a new cpu slab */
	17	FREE_FASTPATH, /* Free to cpu slub */
	18	FREE_SLOWPATH, /* Freeing not to cpu slab */
	19	FREE_FROZEN, /* Freeing to frozen slab */
	20	FREE_ADD_PARTIAL, /* Freeing moves slab to partial list */
	21	FREE_REMOVE_PARTIAL, /* Freeing removes last object */
	22	ALLOC_FROM_PARTIAL, /* Cpu slab acquired from partial list */
	23	ALLOC_SLAB, /* Cpu slab acquired from page allocator */
	24	ALLOC_REFILL, /* Refill cpu slab from slab freelist */
	25	FREE_SLAB, /* Slab freed to the page allocator */
	26	CPUSLAB_FLUSH, /* Abandoning of the cpu slab */
	27	DEACTIVATE_FULL, /* Cpu slab was full when deactivated */
	28	DEACTIVATE_EMPTY, /* Cpu slab was empty when deactivated */
	29	DEACTIVATE_TO_HEAD, /* Cpu slab was moved to the head of partials */
	30	DEACTIVATE_TO_TAIL, /* Cpu slab was moved to the tail of partials */
	31	DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */
	32	ORDER_FALLBACK, /* Number of times fallback was necessary */
	33	NR_SLUB_STAT_ITEMS };
	34
	35	struct kmem_cache_cpu {
	36	void *freelist; / Pointer to first free per cpu object */
	37	struct page page; / The slab from which we are allocating */
	38	int node; /* The node of the page (or -1 for debug) */
	39	unsigned int offset; /* Freepointer offset (in word units) */
	40	unsigned int objsize; /* Size of an object (from kmem_cache) */
	41	#ifdef CONFIG_SLUB_STATS
	42	unsigned stat[NR_SLUB_STAT_ITEMS];
	43	#endif
	44	};
	45
	46	struct kmem_cache_node {
	47	spinlock_t list_lock; /* Protect partial list and nr_partial */
	48	unsigned long nr_partial;
	49	struct list_head partial;
	50	#ifdef CONFIG_SLUB_DEBUG
	51	atomic_long_t nr_slabs;
	52	atomic_long_t total_objects;
	53	struct list_head full;
	54	#endif
	55	};
	56
	57	/*
	58	* Word size structure that can be atomically updated or read and that
	59	* contains both the order and the number of objects that a slab of the
	60	* given order would contain.
	61	*/
	62	struct kmem_cache_order_objects {
	63	unsigned long x;
	64	};
	65
	66	/*
	67	* Slab cache management.
	68	*/
	69	struct kmem_cache {
	70	/* Used for retriving partial slabs etc */
	71	unsigned long flags;
	72	int size; /* The size of an object including meta data */
	73	int objsize; /* The size of an object without meta data */
	74	int offset; /* Free pointer offset. */
	75	struct kmem_cache_order_objects oo;
	76
	77	/*
	78	* Avoid an extra cache line for UP, SMP and for the node local to
	79	* struct kmem_cache.
	80	*/
	81	struct kmem_cache_node local_node;
	82
	83	/* Allocation and freeing of slabs */
	84	struct kmem_cache_order_objects max;
	85	struct kmem_cache_order_objects min;
	86	gfp_t allocflags; /* gfp flags to use on each alloc */
	87	int refcount; /* Refcount for slab cache destroy */
	88	void (ctor)(struct kmem_cache , void *);
	89	int inuse; /* Offset to metadata */
	90	int align; /* Alignment */
	91	const char name; / Name (only for display!) */
	92	struct list_head list; /* List of slab caches */
	93	#ifdef CONFIG_SLUB_DEBUG
	94	struct kobject kobj; /* For sysfs */
	95	#endif
	96
	97	#ifdef CONFIG_NUMA
	98	/*
	99	* Defragmentation by allocating from a remote node.
	100	*/
	101	int remote_node_defrag_ratio;
	102	struct kmem_cache_node *node[MAX_NUMNODES];
	103	#endif
	104	#ifdef CONFIG_SMP
	105	struct kmem_cache_cpu *cpu_slab[NR_CPUS];
	106	#else
	107	struct kmem_cache_cpu cpu_slab;
	108	#endif
	109	};
	110
	111	/*
	112	* Kmalloc subsystem.
	113	*/
	114	#if defined(ARCH_KMALLOC_MINALIGN) && ARCH_KMALLOC_MINALIGN > 8
	115	#define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN
	116	#else
	117	#define KMALLOC_MIN_SIZE 8
	118	#endif
	119
	120	#define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
	121
	122	/*
	123	* We keep the general caches in an array of slab caches that are used for
	124	* 2^x bytes of allocations.
	125	*/
	126	extern struct kmem_cache kmalloc_caches[PAGE_SHIFT + 1];
	127
	128	/*
	129	* Sorry that the following has to be that ugly but some versions of GCC
	130	* have trouble with constant propagation and loops.
	131	*/
	132	static __always_inline int kmalloc_index(size_t size)
	133	{
	134	if (!size)
	135	return 0;
	136
	137	if (size <= KMALLOC_MIN_SIZE)
	138	return KMALLOC_SHIFT_LOW;
	139
	140	#if KMALLOC_MIN_SIZE <= 64
	141	if (size > 64 && size <= 96)
	142	return 1;
	143	if (size > 128 && size <= 192)
	144	return 2;
	145	#endif
	146	if (size <= 8) return 3;
	147	if (size <= 16) return 4;
	148	if (size <= 32) return 5;
	149	if (size <= 64) return 6;
	150	if (size <= 128) return 7;
	151	if (size <= 256) return 8;
	152	if (size <= 512) return 9;
	153	if (size <= 1024) return 10;
	154	if (size <= 2 * 1024) return 11;
	155	if (size <= 4 * 1024) return 12;
	156	/*
	157	* The following is only needed to support architectures with a larger page
	158	* size than 4k.
	159	*/
	160	if (size <= 8 * 1024) return 13;
	161	if (size <= 16 * 1024) return 14;
	162	if (size <= 32 * 1024) return 15;
	163	if (size <= 64 * 1024) return 16;
	164	if (size <= 128 * 1024) return 17;
	165	if (size <= 256 * 1024) return 18;
	166	if (size <= 512 * 1024) return 19;
	167	if (size <= 1024 * 1024) return 20;
	168	if (size <= 2 * 1024 * 1024) return 21;
	169	return -1;
	170
	171	/*
	172	* What we really wanted to do and cannot do because of compiler issues is:
	173	* int i;
	174	* for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
	175	* if (size <= (1 << i))
	176	* return i;
	177	*/
	178	}
	179
	180	/*
	181	* Find the slab cache for a given combination of allocation flags and size.
	182	*
	183	* This ought to end up with a global pointer to the right cache
	184	* in kmalloc_caches.
	185	*/
	186	static __always_inline struct kmem_cache *kmalloc_slab(size_t size)
	187	{
	188	int index = kmalloc_index(size);
	189
	190	if (index == 0)
	191	return NULL;
	192
	193	return &kmalloc_caches[index];
	194	}
	195
	196	#ifdef CONFIG_ZONE_DMA
	197	#define SLUB_DMA __GFP_DMA
	198	#else
	199	/* Disable DMA functionality */
	200	#define SLUB_DMA (__force gfp_t)0
	201	#endif
	202
	203	void kmem_cache_alloc(struct kmem_cache , gfp_t);
	204	void *__kmalloc(size_t size, gfp_t flags);
	205
	206	static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
	207	{
	208	return (void *)__get_free_pages(flags \| __GFP_COMP, get_order(size));
	209	}
	210
	211	static __always_inline void *kmalloc(size_t size, gfp_t flags)
	212	{
	213	if (__builtin_constant_p(size)) {
	214	if (size > PAGE_SIZE)
	215	return kmalloc_large(size, flags);
	216
	217	if (!(flags & SLUB_DMA)) {
	218	struct kmem_cache *s = kmalloc_slab(size);
	219
	220	if (!s)
	221	return ZERO_SIZE_PTR;
	222
	223	return kmem_cache_alloc(s, flags);
	224	}
	225	}
	226	return __kmalloc(size, flags);
	227	}
	228
	229	#ifdef CONFIG_NUMA
	230	void *__kmalloc_node(size_t size, gfp_t flags, int node);
	231	void kmem_cache_alloc_node(struct kmem_cache , gfp_t flags, int node);
	232
	233	static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
	234	{
	235	if (__builtin_constant_p(size) &&
	236	size <= PAGE_SIZE && !(flags & SLUB_DMA)) {
	237	struct kmem_cache *s = kmalloc_slab(size);
	238
	239	if (!s)
	240	return ZERO_SIZE_PTR;
	241
	242	return kmem_cache_alloc_node(s, flags, node);
	243	}
	244	return __kmalloc_node(size, flags, node);
	245	}
	246	#endif
	247
	248	#endif /* _LINUX_SLUB_DEF_H */