[linux-2.6-block.git] / include / linux / percpu.h

#ifndef __LINUX_PERCPU_H
#define __LINUX_PERCPU_H

#include <linux/mmdebug.h>
#include <linux/preempt.h>
#include <linux/smp.h>
#include <linux/cpumask.h>
#include <linux/pfn.h>
#include <linux/init.h>

#include <asm/percpu.h>

/* enough to cover all DEFINE_PER_CPUs in modules */
#ifdef CONFIG_MODULES
#define PERCPU_MODULE_RESERVE		(8 << 10)
#else
#define PERCPU_MODULE_RESERVE		0
#endif

#ifndef PERCPU_ENOUGH_ROOM
#define PERCPU_ENOUGH_ROOM						\
	(ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) +	\
	 PERCPU_MODULE_RESERVE)
#endif

/* minimum unit size, also is the maximum supported allocation size */
#define PCPU_MIN_UNIT_SIZE		PFN_ALIGN(32 << 10)

/*
 * Percpu allocator can serve percpu allocations before slab is
 * initialized which allows slab to depend on the percpu allocator.
 * The following two parameters decide how much resource to
 * preallocate for this.  Keep PERCPU_DYNAMIC_RESERVE equal to or
 * larger than PERCPU_DYNAMIC_EARLY_SIZE.
 */
#define PERCPU_DYNAMIC_EARLY_SLOTS	128
#define PERCPU_DYNAMIC_EARLY_SIZE	(12 << 10)

/*
 * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
 * back on the first chunk for dynamic percpu allocation if arch is
 * manually allocating and mapping it for faster access (as a part of
 * large page mapping for example).
 *
 * The following values give between one and two pages of free space
 * after typical minimal boot (2-way SMP, single disk and NIC) with
 * both defconfig and a distro config on x86_64 and 32.  More
 * intelligent way to determine this would be nice.
 */
#if BITS_PER_LONG > 32
#define PERCPU_DYNAMIC_RESERVE		(28 << 10)
#else
#define PERCPU_DYNAMIC_RESERVE		(20 << 10)
#endif

extern void *pcpu_base_addr;
extern const unsigned long *pcpu_unit_offsets;

struct pcpu_group_info {
	int			nr_units;	/* aligned # of units */
	unsigned long		base_offset;	/* base address offset */
	unsigned int		*cpu_map;	/* unit->cpu map, empty
						 * entries contain NR_CPUS */
};

struct pcpu_alloc_info {
	size_t			static_size;
	size_t			reserved_size;
	size_t			dyn_size;
	size_t			unit_size;
	size_t			atom_size;
	size_t			alloc_size;
	size_t			__ai_size;	/* internal, don't use */
	int			nr_groups;	/* 0 if grouping unnecessary */
	struct pcpu_group_info	groups[];
};

enum pcpu_fc {
	PCPU_FC_AUTO,
	PCPU_FC_EMBED,
	PCPU_FC_PAGE,

	PCPU_FC_NR,
};
extern const char * const pcpu_fc_names[PCPU_FC_NR];

extern enum pcpu_fc pcpu_chosen_fc;

typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
				     size_t align);
typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);

extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
							     int nr_units);
extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);

extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
					 void *base_addr);

#ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
				size_t atom_size,
				pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
				pcpu_fc_alloc_fn_t alloc_fn,
				pcpu_fc_free_fn_t free_fn);
#endif

#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
extern int __init pcpu_page_first_chunk(size_t reserved_size,
				pcpu_fc_alloc_fn_t alloc_fn,
				pcpu_fc_free_fn_t free_fn,
				pcpu_fc_populate_pte_fn_t populate_pte_fn);
#endif

extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
extern bool is_kernel_percpu_address(unsigned long addr);

#if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
extern void __init setup_per_cpu_areas(void);
#endif
extern void __init percpu_init_late(void);

extern void __percpu *__alloc_percpu_gfp(size_t size, size_t align, gfp_t gfp);
extern void __percpu *__alloc_percpu(size_t size, size_t align);
extern void free_percpu(void __percpu *__pdata);
extern phys_addr_t per_cpu_ptr_to_phys(void *addr);

#define alloc_percpu_gfp(type, gfp)					\
	(typeof(type) __percpu *)__alloc_percpu_gfp(sizeof(type),	\
						__alignof__(type), gfp)
#define alloc_percpu(type)						\
	(typeof(type) __percpu *)__alloc_percpu(sizeof(type),		\
						__alignof__(type))

#endif /* __LINUX_PERCPU_H */
Commit	Line	Data
1da177e4 LT	1	#ifndef __LINUX_PERCPU_H
1da177e4 LT	2	#define __LINUX_PERCPU_H
7ff6f082	3
309381fe	4	#include <linux/mmdebug.h>
0a3021f4	5	#include <linux/preempt.h>
1da177e4	6	#include <linux/smp.h>
7ff6f082	7	#include <linux/cpumask.h>
6a242909	8	#include <linux/pfn.h>
de380b55	9	#include <linux/init.h>
7ff6f082	10
1da177e4 LT	11	#include <asm/percpu.h>
1da177e4 LT	12
6a242909	13	/* enough to cover all DEFINE_PER_CPUs in modules */
b00742d3	14	#ifdef CONFIG_MODULES
6a242909	15	#define PERCPU_MODULE_RESERVE (8 << 10)
b00742d3	16	#else
6a242909	17	#define PERCPU_MODULE_RESERVE 0
1da177e4 LT	18	#endif
1da177e4 LT	19
6a242909	20	#ifndef PERCPU_ENOUGH_ROOM
b00742d3	21	#define PERCPU_ENOUGH_ROOM \
6a242909 TH	22	(ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \
	23	PERCPU_MODULE_RESERVE)
	24	#endif
b00742d3	25
8d408b4b	26	/* minimum unit size, also is the maximum supported allocation size */
6abad5ac	27	#define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10)
8d408b4b	28
099a19d9 TH	29	/*
	30	* Percpu allocator can serve percpu allocations before slab is
	31	* initialized which allows slab to depend on the percpu allocator.
	32	* The following two parameters decide how much resource to
	33	* preallocate for this. Keep PERCPU_DYNAMIC_RESERVE equal to or
	34	* larger than PERCPU_DYNAMIC_EARLY_SIZE.
	35	*/
	36	#define PERCPU_DYNAMIC_EARLY_SLOTS 128
	37	#define PERCPU_DYNAMIC_EARLY_SIZE (12 << 10)
	38
8d408b4b TH	39	/*
8d408b4b TH	40	* PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
6b19b0c2 TH	41	* back on the first chunk for dynamic percpu allocation if arch is
	42	* manually allocating and mapping it for faster access (as a part of
	43	* large page mapping for example).
8d408b4b	44	*
6b19b0c2 TH	45	* The following values give between one and two pages of free space
	46	* after typical minimal boot (2-way SMP, single disk and NIC) with
	47	* both defconfig and a distro config on x86_64 and 32. More
	48	* intelligent way to determine this would be nice.
8d408b4b	49	*/
6b19b0c2	50	#if BITS_PER_LONG > 32
1a4d7607	51	#define PERCPU_DYNAMIC_RESERVE (28 << 10)
6b19b0c2	52	#else
1a4d7607	53	#define PERCPU_DYNAMIC_RESERVE (20 << 10)
6b19b0c2	54	#endif
8d408b4b	55
fbf59bc9	56	extern void *pcpu_base_addr;
fb435d52	57	extern const unsigned long *pcpu_unit_offsets;
1da177e4	58
fd1e8a1f TH	59	struct pcpu_group_info {
	60	int nr_units; /* aligned # of units */
	61	unsigned long base_offset; /* base address offset */
	62	unsigned int cpu_map; / unit->cpu map, empty
	63	* entries contain NR_CPUS */
	64	};
	65
	66	struct pcpu_alloc_info {
	67	size_t static_size;
	68	size_t reserved_size;
	69	size_t dyn_size;
	70	size_t unit_size;
	71	size_t atom_size;
	72	size_t alloc_size;
	73	size_t __ai_size; /* internal, don't use */
	74	int nr_groups; /* 0 if grouping unnecessary */
	75	struct pcpu_group_info groups[];
	76	};
	77
f58dc01b TH	78	enum pcpu_fc {
	79	PCPU_FC_AUTO,
	80	PCPU_FC_EMBED,
	81	PCPU_FC_PAGE,
f58dc01b TH	82
	83	PCPU_FC_NR,
	84	};
17f3609c	85	extern const char * const pcpu_fc_names[PCPU_FC_NR];
f58dc01b TH	86
	87	extern enum pcpu_fc pcpu_chosen_fc;
	88
3cbc8565 TH	89	typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
3cbc8565 TH	90	size_t align);
d4b95f80 TH	91	typedef void (pcpu_fc_free_fn_t)(void ptr, size_t size);
d4b95f80 TH	92	typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
a530b795	93	typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
fbf59bc9	94
fd1e8a1f TH	95	extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
	96	int nr_units);
	97	extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
	98
fb435d52 TH	99	extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
fb435d52 TH	100	void *base_addr);
8d408b4b	101
08fc4580	102	#ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
4ba6ce25	103	extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
c8826dd5 TH	104	size_t atom_size,
	105	pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
	106	pcpu_fc_alloc_fn_t alloc_fn,
	107	pcpu_fc_free_fn_t free_fn);
08fc4580	108	#endif
66c3a757	109
08fc4580	110	#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
fb435d52	111	extern int __init pcpu_page_first_chunk(size_t reserved_size,
d4b95f80 TH	112	pcpu_fc_alloc_fn_t alloc_fn,
	113	pcpu_fc_free_fn_t free_fn,
	114	pcpu_fc_populate_pte_fn_t populate_pte_fn);
08fc4580	115	#endif
d4b95f80	116
e0fdb0e0	117	extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
10fad5e4	118	extern bool is_kernel_percpu_address(unsigned long addr);
1da177e4	119
bbddff05	120	#if !defined(CONFIG_SMP) \|\| !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
e74e3962 TH	121	extern void __init setup_per_cpu_areas(void);
e74e3962 TH	122	#endif
099a19d9	123	extern void __init percpu_init_late(void);
e74e3962	124
5835d96e	125	extern void __percpu *__alloc_percpu_gfp(size_t size, size_t align, gfp_t gfp);
de380b55 TH	126	extern void __percpu *__alloc_percpu(size_t size, size_t align);
	127	extern void free_percpu(void __percpu *__pdata);
	128	extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
	129
5835d96e TH	130	#define alloc_percpu_gfp(type, gfp) \
	131	(typeof(type) __percpu *)__alloc_percpu_gfp(sizeof(type), \
	132	__alignof__(type), gfp)
	133	#define alloc_percpu(type) \
	134	(typeof(type) __percpu *)__alloc_percpu(sizeof(type), \
	135	__alignof__(type))
1da177e4 LT	136
1da177e4 LT	137	#endif /* __LINUX_PERCPU_H */