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Release 4.12 include/linux/percpu.h

Directory: include/linux
#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 */

#define PERCPU_MODULE_RESERVE		(8 << 10)


/* 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


#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)

#define PERCPU_DYNAMIC_RESERVE		(20 << 10)

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 {

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);

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);

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);

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

#endif /* __LINUX_PERCPU_H */

Overall Contributors

Tejun Heo39986.18%2767.50%
Jeremy Fitzhardinge143.02%12.50%
Thomas Gleixner143.02%12.50%
Rusty Russell132.81%25.00%
Andrew Morton112.38%37.50%
Sasha Levin30.65%12.50%
Steven Rostedt30.65%12.50%
Martin Peschke20.43%12.50%
Christoph Lameter20.43%12.50%
Andi Kleen10.22%12.50%
Robert P. J. Day10.22%12.50%
Directory: include/linux
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