[mirror_ubuntu-zesty-kernel.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/printk.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))

/* To avoid include hell, as printk can not declare this, we declare it here */
DECLARE_PER_CPU(printk_func_t, printk_func);

#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>
04b74b27	8	#include <linux/printk.h>
6a242909	9	#include <linux/pfn.h>
de380b55	10	#include <linux/init.h>
7ff6f082	11
1da177e4 LT	12	#include <asm/percpu.h>
1da177e4 LT	13
6a242909	14	/* enough to cover all DEFINE_PER_CPUs in modules */
b00742d3	15	#ifdef CONFIG_MODULES
6a242909	16	#define PERCPU_MODULE_RESERVE (8 << 10)
b00742d3	17	#else
6a242909	18	#define PERCPU_MODULE_RESERVE 0
1da177e4 LT	19	#endif
1da177e4 LT	20
6a242909	21	#ifndef PERCPU_ENOUGH_ROOM
b00742d3	22	#define PERCPU_ENOUGH_ROOM \
6a242909 TH	23	(ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \
	24	PERCPU_MODULE_RESERVE)
	25	#endif
b00742d3	26
8d408b4b	27	/* minimum unit size, also is the maximum supported allocation size */
6abad5ac	28	#define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10)
8d408b4b	29
099a19d9 TH	30	/*
	31	* Percpu allocator can serve percpu allocations before slab is
	32	* initialized which allows slab to depend on the percpu allocator.
	33	* The following two parameters decide how much resource to
	34	* preallocate for this. Keep PERCPU_DYNAMIC_RESERVE equal to or
	35	* larger than PERCPU_DYNAMIC_EARLY_SIZE.
	36	*/
	37	#define PERCPU_DYNAMIC_EARLY_SLOTS 128
	38	#define PERCPU_DYNAMIC_EARLY_SIZE (12 << 10)
	39
8d408b4b TH	40	/*
8d408b4b TH	41	* PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
6b19b0c2 TH	42	* back on the first chunk for dynamic percpu allocation if arch is
	43	* manually allocating and mapping it for faster access (as a part of
	44	* large page mapping for example).
8d408b4b	45	*
6b19b0c2 TH	46	* The following values give between one and two pages of free space
	47	* after typical minimal boot (2-way SMP, single disk and NIC) with
	48	* both defconfig and a distro config on x86_64 and 32. More
	49	* intelligent way to determine this would be nice.
8d408b4b	50	*/
6b19b0c2	51	#if BITS_PER_LONG > 32
1a4d7607	52	#define PERCPU_DYNAMIC_RESERVE (28 << 10)
6b19b0c2	53	#else
1a4d7607	54	#define PERCPU_DYNAMIC_RESERVE (20 << 10)
6b19b0c2	55	#endif
8d408b4b	56
fbf59bc9	57	extern void *pcpu_base_addr;
fb435d52	58	extern const unsigned long *pcpu_unit_offsets;
1da177e4	59
fd1e8a1f TH	60	struct pcpu_group_info {
	61	int nr_units; /* aligned # of units */
	62	unsigned long base_offset; /* base address offset */
	63	unsigned int cpu_map; / unit->cpu map, empty
	64	* entries contain NR_CPUS */
	65	};
	66
	67	struct pcpu_alloc_info {
	68	size_t static_size;
	69	size_t reserved_size;
	70	size_t dyn_size;
	71	size_t unit_size;
	72	size_t atom_size;
	73	size_t alloc_size;
	74	size_t __ai_size; /* internal, don't use */
	75	int nr_groups; /* 0 if grouping unnecessary */
	76	struct pcpu_group_info groups[];
	77	};
	78
f58dc01b TH	79	enum pcpu_fc {
	80	PCPU_FC_AUTO,
	81	PCPU_FC_EMBED,
	82	PCPU_FC_PAGE,
f58dc01b TH	83
	84	PCPU_FC_NR,
	85	};
17f3609c	86	extern const char * const pcpu_fc_names[PCPU_FC_NR];
f58dc01b TH	87
	88	extern enum pcpu_fc pcpu_chosen_fc;
	89
3cbc8565 TH	90	typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
3cbc8565 TH	91	size_t align);
d4b95f80 TH	92	typedef void (pcpu_fc_free_fn_t)(void ptr, size_t size);
d4b95f80 TH	93	typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
a530b795	94	typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
fbf59bc9	95
fd1e8a1f TH	96	extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
	97	int nr_units);
	98	extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
	99
fb435d52 TH	100	extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
fb435d52 TH	101	void *base_addr);
8d408b4b	102
08fc4580	103	#ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
4ba6ce25	104	extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
c8826dd5 TH	105	size_t atom_size,
	106	pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
	107	pcpu_fc_alloc_fn_t alloc_fn,
	108	pcpu_fc_free_fn_t free_fn);
08fc4580	109	#endif
66c3a757	110
08fc4580	111	#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
fb435d52	112	extern int __init pcpu_page_first_chunk(size_t reserved_size,
d4b95f80 TH	113	pcpu_fc_alloc_fn_t alloc_fn,
	114	pcpu_fc_free_fn_t free_fn,
	115	pcpu_fc_populate_pte_fn_t populate_pte_fn);
08fc4580	116	#endif
d4b95f80	117
e0fdb0e0	118	extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
10fad5e4	119	extern bool is_kernel_percpu_address(unsigned long addr);
1da177e4	120
bbddff05	121	#if !defined(CONFIG_SMP) \|\| !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
e74e3962 TH	122	extern void __init setup_per_cpu_areas(void);
e74e3962 TH	123	#endif
099a19d9	124	extern void __init percpu_init_late(void);
e74e3962	125
5835d96e	126	extern void __percpu *__alloc_percpu_gfp(size_t size, size_t align, gfp_t gfp);
de380b55 TH	127	extern void __percpu *__alloc_percpu(size_t size, size_t align);
	128	extern void free_percpu(void __percpu *__pdata);
	129	extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
	130
5835d96e TH	131	#define alloc_percpu_gfp(type, gfp) \
	132	(typeof(type) __percpu *)__alloc_percpu_gfp(sizeof(type), \
	133	__alignof__(type), gfp)
	134	#define alloc_percpu(type) \
	135	(typeof(type) __percpu *)__alloc_percpu(sizeof(type), \
	136	__alignof__(type))
1da177e4	137
afdc34a3 SRRH	138	/* To avoid include hell, as printk can not declare this, we declare it here */
	139	DECLARE_PER_CPU(printk_func_t, printk_func);
	140
1da177e4	141	#endif /* __LINUX_PERCPU_H */