linux_dsm_epyc7002/include/linux/percpu.h
Namhyung Kim 18cb2aef91 percpu: handle __percpu notations in UP accessors
UP accessors didn't take care of __percpu notations leading to a lot
of spurious sparse warnings on UP configurations.  Fix it.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2010-08-07 14:20:53 +02:00

634 lines
20 KiB
C

#ifndef __LINUX_PERCPU_H
#define __LINUX_PERCPU_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
/*
* Must be an lvalue. Since @var must be a simple identifier,
* we force a syntax error here if it isn't.
*/
#define get_cpu_var(var) (*({ \
preempt_disable(); \
&__get_cpu_var(var); }))
/*
* The weird & is necessary because sparse considers (void)(var) to be
* a direct dereference of percpu variable (var).
*/
#define put_cpu_var(var) do { \
(void)&(var); \
preempt_enable(); \
} while (0)
#ifdef CONFIG_SMP
/* minimum unit size, also is the maximum supported allocation size */
#define PCPU_MIN_UNIT_SIZE PFN_ALIGN(64 << 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 (20 << 10)
#else
#define PERCPU_DYNAMIC_RESERVE (12 << 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 *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
/*
* Use this to get to a cpu's version of the per-cpu object
* dynamically allocated. Non-atomic access to the current CPU's
* version should probably be combined with get_cpu()/put_cpu().
*/
#define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
extern bool is_kernel_percpu_address(unsigned long addr);
#ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
extern void __init setup_per_cpu_areas(void);
#endif
extern void __init percpu_init_late(void);
#else /* CONFIG_SMP */
#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); VERIFY_PERCPU_PTR((ptr)); })
/* can't distinguish from other static vars, always false */
static inline bool is_kernel_percpu_address(unsigned long addr)
{
return false;
}
static inline void __init setup_per_cpu_areas(void) { }
static inline void __init percpu_init_late(void) { }
static inline void *pcpu_lpage_remapped(void *kaddr)
{
return NULL;
}
#endif /* CONFIG_SMP */
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(type) \
(typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type))
/*
* Optional methods for optimized non-lvalue per-cpu variable access.
*
* @var can be a percpu variable or a field of it and its size should
* equal char, int or long. percpu_read() evaluates to a lvalue and
* all others to void.
*
* These operations are guaranteed to be atomic w.r.t. preemption.
* The generic versions use plain get/put_cpu_var(). Archs are
* encouraged to implement single-instruction alternatives which don't
* require preemption protection.
*/
#ifndef percpu_read
# define percpu_read(var) \
({ \
typeof(var) *pr_ptr__ = &(var); \
typeof(var) pr_ret__; \
pr_ret__ = get_cpu_var(*pr_ptr__); \
put_cpu_var(*pr_ptr__); \
pr_ret__; \
})
#endif
#define __percpu_generic_to_op(var, val, op) \
do { \
typeof(var) *pgto_ptr__ = &(var); \
get_cpu_var(*pgto_ptr__) op val; \
put_cpu_var(*pgto_ptr__); \
} while (0)
#ifndef percpu_write
# define percpu_write(var, val) __percpu_generic_to_op(var, (val), =)
#endif
#ifndef percpu_add
# define percpu_add(var, val) __percpu_generic_to_op(var, (val), +=)
#endif
#ifndef percpu_sub
# define percpu_sub(var, val) __percpu_generic_to_op(var, (val), -=)
#endif
#ifndef percpu_and
# define percpu_and(var, val) __percpu_generic_to_op(var, (val), &=)
#endif
#ifndef percpu_or
# define percpu_or(var, val) __percpu_generic_to_op(var, (val), |=)
#endif
#ifndef percpu_xor
# define percpu_xor(var, val) __percpu_generic_to_op(var, (val), ^=)
#endif
/*
* Branching function to split up a function into a set of functions that
* are called for different scalar sizes of the objects handled.
*/
extern void __bad_size_call_parameter(void);
#define __pcpu_size_call_return(stem, variable) \
({ typeof(variable) pscr_ret__; \
__verify_pcpu_ptr(&(variable)); \
switch(sizeof(variable)) { \
case 1: pscr_ret__ = stem##1(variable);break; \
case 2: pscr_ret__ = stem##2(variable);break; \
case 4: pscr_ret__ = stem##4(variable);break; \
case 8: pscr_ret__ = stem##8(variable);break; \
default: \
__bad_size_call_parameter();break; \
} \
pscr_ret__; \
})
#define __pcpu_size_call(stem, variable, ...) \
do { \
__verify_pcpu_ptr(&(variable)); \
switch(sizeof(variable)) { \
case 1: stem##1(variable, __VA_ARGS__);break; \
case 2: stem##2(variable, __VA_ARGS__);break; \
case 4: stem##4(variable, __VA_ARGS__);break; \
case 8: stem##8(variable, __VA_ARGS__);break; \
default: \
__bad_size_call_parameter();break; \
} \
} while (0)
/*
* Optimized manipulation for memory allocated through the per cpu
* allocator or for addresses of per cpu variables.
*
* These operation guarantee exclusivity of access for other operations
* on the *same* processor. The assumption is that per cpu data is only
* accessed by a single processor instance (the current one).
*
* The first group is used for accesses that must be done in a
* preemption safe way since we know that the context is not preempt
* safe. Interrupts may occur. If the interrupt modifies the variable
* too then RMW actions will not be reliable.
*
* The arch code can provide optimized functions in two ways:
*
* 1. Override the function completely. F.e. define this_cpu_add().
* The arch must then ensure that the various scalar format passed
* are handled correctly.
*
* 2. Provide functions for certain scalar sizes. F.e. provide
* this_cpu_add_2() to provide per cpu atomic operations for 2 byte
* sized RMW actions. If arch code does not provide operations for
* a scalar size then the fallback in the generic code will be
* used.
*/
#define _this_cpu_generic_read(pcp) \
({ typeof(pcp) ret__; \
preempt_disable(); \
ret__ = *this_cpu_ptr(&(pcp)); \
preempt_enable(); \
ret__; \
})
#ifndef this_cpu_read
# ifndef this_cpu_read_1
# define this_cpu_read_1(pcp) _this_cpu_generic_read(pcp)
# endif
# ifndef this_cpu_read_2
# define this_cpu_read_2(pcp) _this_cpu_generic_read(pcp)
# endif
# ifndef this_cpu_read_4
# define this_cpu_read_4(pcp) _this_cpu_generic_read(pcp)
# endif
# ifndef this_cpu_read_8
# define this_cpu_read_8(pcp) _this_cpu_generic_read(pcp)
# endif
# define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp))
#endif
#define _this_cpu_generic_to_op(pcp, val, op) \
do { \
preempt_disable(); \
*__this_cpu_ptr(&(pcp)) op val; \
preempt_enable(); \
} while (0)
#ifndef this_cpu_write
# ifndef this_cpu_write_1
# define this_cpu_write_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
# endif
# ifndef this_cpu_write_2
# define this_cpu_write_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
# endif
# ifndef this_cpu_write_4
# define this_cpu_write_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
# endif
# ifndef this_cpu_write_8
# define this_cpu_write_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
# endif
# define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val))
#endif
#ifndef this_cpu_add
# ifndef this_cpu_add_1
# define this_cpu_add_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef this_cpu_add_2
# define this_cpu_add_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef this_cpu_add_4
# define this_cpu_add_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef this_cpu_add_8
# define this_cpu_add_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
# endif
# define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val))
#endif
#ifndef this_cpu_sub
# define this_cpu_sub(pcp, val) this_cpu_add((pcp), -(val))
#endif
#ifndef this_cpu_inc
# define this_cpu_inc(pcp) this_cpu_add((pcp), 1)
#endif
#ifndef this_cpu_dec
# define this_cpu_dec(pcp) this_cpu_sub((pcp), 1)
#endif
#ifndef this_cpu_and
# ifndef this_cpu_and_1
# define this_cpu_and_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef this_cpu_and_2
# define this_cpu_and_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef this_cpu_and_4
# define this_cpu_and_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef this_cpu_and_8
# define this_cpu_and_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
# endif
# define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val))
#endif
#ifndef this_cpu_or
# ifndef this_cpu_or_1
# define this_cpu_or_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef this_cpu_or_2
# define this_cpu_or_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef this_cpu_or_4
# define this_cpu_or_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef this_cpu_or_8
# define this_cpu_or_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
# endif
# define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
#endif
#ifndef this_cpu_xor
# ifndef this_cpu_xor_1
# define this_cpu_xor_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
# endif
# ifndef this_cpu_xor_2
# define this_cpu_xor_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
# endif
# ifndef this_cpu_xor_4
# define this_cpu_xor_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
# endif
# ifndef this_cpu_xor_8
# define this_cpu_xor_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
# endif
# define this_cpu_xor(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
#endif
/*
* Generic percpu operations that do not require preemption handling.
* Either we do not care about races or the caller has the
* responsibility of handling preemptions issues. Arch code can still
* override these instructions since the arch per cpu code may be more
* efficient and may actually get race freeness for free (that is the
* case for x86 for example).
*
* If there is no other protection through preempt disable and/or
* disabling interupts then one of these RMW operations can show unexpected
* behavior because the execution thread was rescheduled on another processor
* or an interrupt occurred and the same percpu variable was modified from
* the interrupt context.
*/
#ifndef __this_cpu_read
# ifndef __this_cpu_read_1
# define __this_cpu_read_1(pcp) (*__this_cpu_ptr(&(pcp)))
# endif
# ifndef __this_cpu_read_2
# define __this_cpu_read_2(pcp) (*__this_cpu_ptr(&(pcp)))
# endif
# ifndef __this_cpu_read_4
# define __this_cpu_read_4(pcp) (*__this_cpu_ptr(&(pcp)))
# endif
# ifndef __this_cpu_read_8
# define __this_cpu_read_8(pcp) (*__this_cpu_ptr(&(pcp)))
# endif
# define __this_cpu_read(pcp) __pcpu_size_call_return(__this_cpu_read_, (pcp))
#endif
#define __this_cpu_generic_to_op(pcp, val, op) \
do { \
*__this_cpu_ptr(&(pcp)) op val; \
} while (0)
#ifndef __this_cpu_write
# ifndef __this_cpu_write_1
# define __this_cpu_write_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
# endif
# ifndef __this_cpu_write_2
# define __this_cpu_write_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
# endif
# ifndef __this_cpu_write_4
# define __this_cpu_write_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
# endif
# ifndef __this_cpu_write_8
# define __this_cpu_write_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
# endif
# define __this_cpu_write(pcp, val) __pcpu_size_call(__this_cpu_write_, (pcp), (val))
#endif
#ifndef __this_cpu_add
# ifndef __this_cpu_add_1
# define __this_cpu_add_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef __this_cpu_add_2
# define __this_cpu_add_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef __this_cpu_add_4
# define __this_cpu_add_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef __this_cpu_add_8
# define __this_cpu_add_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
# endif
# define __this_cpu_add(pcp, val) __pcpu_size_call(__this_cpu_add_, (pcp), (val))
#endif
#ifndef __this_cpu_sub
# define __this_cpu_sub(pcp, val) __this_cpu_add((pcp), -(val))
#endif
#ifndef __this_cpu_inc
# define __this_cpu_inc(pcp) __this_cpu_add((pcp), 1)
#endif
#ifndef __this_cpu_dec
# define __this_cpu_dec(pcp) __this_cpu_sub((pcp), 1)
#endif
#ifndef __this_cpu_and
# ifndef __this_cpu_and_1
# define __this_cpu_and_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef __this_cpu_and_2
# define __this_cpu_and_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef __this_cpu_and_4
# define __this_cpu_and_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef __this_cpu_and_8
# define __this_cpu_and_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
# endif
# define __this_cpu_and(pcp, val) __pcpu_size_call(__this_cpu_and_, (pcp), (val))
#endif
#ifndef __this_cpu_or
# ifndef __this_cpu_or_1
# define __this_cpu_or_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef __this_cpu_or_2
# define __this_cpu_or_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef __this_cpu_or_4
# define __this_cpu_or_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef __this_cpu_or_8
# define __this_cpu_or_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
# endif
# define __this_cpu_or(pcp, val) __pcpu_size_call(__this_cpu_or_, (pcp), (val))
#endif
#ifndef __this_cpu_xor
# ifndef __this_cpu_xor_1
# define __this_cpu_xor_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
# endif
# ifndef __this_cpu_xor_2
# define __this_cpu_xor_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
# endif
# ifndef __this_cpu_xor_4
# define __this_cpu_xor_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
# endif
# ifndef __this_cpu_xor_8
# define __this_cpu_xor_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
# endif
# define __this_cpu_xor(pcp, val) __pcpu_size_call(__this_cpu_xor_, (pcp), (val))
#endif
/*
* IRQ safe versions of the per cpu RMW operations. Note that these operations
* are *not* safe against modification of the same variable from another
* processors (which one gets when using regular atomic operations)
. They are guaranteed to be atomic vs. local interrupts and
* preemption only.
*/
#define irqsafe_cpu_generic_to_op(pcp, val, op) \
do { \
unsigned long flags; \
local_irq_save(flags); \
*__this_cpu_ptr(&(pcp)) op val; \
local_irq_restore(flags); \
} while (0)
#ifndef irqsafe_cpu_add
# ifndef irqsafe_cpu_add_1
# define irqsafe_cpu_add_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef irqsafe_cpu_add_2
# define irqsafe_cpu_add_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef irqsafe_cpu_add_4
# define irqsafe_cpu_add_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
# endif
# ifndef irqsafe_cpu_add_8
# define irqsafe_cpu_add_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
# endif
# define irqsafe_cpu_add(pcp, val) __pcpu_size_call(irqsafe_cpu_add_, (pcp), (val))
#endif
#ifndef irqsafe_cpu_sub
# define irqsafe_cpu_sub(pcp, val) irqsafe_cpu_add((pcp), -(val))
#endif
#ifndef irqsafe_cpu_inc
# define irqsafe_cpu_inc(pcp) irqsafe_cpu_add((pcp), 1)
#endif
#ifndef irqsafe_cpu_dec
# define irqsafe_cpu_dec(pcp) irqsafe_cpu_sub((pcp), 1)
#endif
#ifndef irqsafe_cpu_and
# ifndef irqsafe_cpu_and_1
# define irqsafe_cpu_and_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef irqsafe_cpu_and_2
# define irqsafe_cpu_and_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef irqsafe_cpu_and_4
# define irqsafe_cpu_and_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
# endif
# ifndef irqsafe_cpu_and_8
# define irqsafe_cpu_and_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
# endif
# define irqsafe_cpu_and(pcp, val) __pcpu_size_call(irqsafe_cpu_and_, (val))
#endif
#ifndef irqsafe_cpu_or
# ifndef irqsafe_cpu_or_1
# define irqsafe_cpu_or_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef irqsafe_cpu_or_2
# define irqsafe_cpu_or_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef irqsafe_cpu_or_4
# define irqsafe_cpu_or_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
# endif
# ifndef irqsafe_cpu_or_8
# define irqsafe_cpu_or_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
# endif
# define irqsafe_cpu_or(pcp, val) __pcpu_size_call(irqsafe_cpu_or_, (val))
#endif
#ifndef irqsafe_cpu_xor
# ifndef irqsafe_cpu_xor_1
# define irqsafe_cpu_xor_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
# endif
# ifndef irqsafe_cpu_xor_2
# define irqsafe_cpu_xor_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
# endif
# ifndef irqsafe_cpu_xor_4
# define irqsafe_cpu_xor_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
# endif
# ifndef irqsafe_cpu_xor_8
# define irqsafe_cpu_xor_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
# endif
# define irqsafe_cpu_xor(pcp, val) __pcpu_size_call(irqsafe_cpu_xor_, (val))
#endif
#endif /* __LINUX_PERCPU_H */