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#ifndef __LINUX_PERCPU_H
#define __LINUX_PERCPU_H
#include <linux/preempt.h>
#include <linux/slab.h> /* For kmalloc() */
#include <linux/smp.h>
#include <linux/cpumask.h>
#include <asm/percpu.h>
#ifndef PER_CPU_BASE_SECTION
#ifdef CONFIG_SMP
#define PER_CPU_BASE_SECTION ".data.percpu"
#else
#define PER_CPU_BASE_SECTION ".data"
#endif
#endif
#ifdef CONFIG_SMP
#ifdef MODULE
#define PER_CPU_SHARED_ALIGNED_SECTION ""
#else
#define PER_CPU_SHARED_ALIGNED_SECTION ".shared_aligned"
#endif
#define PER_CPU_FIRST_SECTION ".first"
#else
#define PER_CPU_SHARED_ALIGNED_SECTION ""
#define PER_CPU_FIRST_SECTION ""
#endif
#define DEFINE_PER_CPU_SECTION(type, name, section) \
__attribute__((__section__(PER_CPU_BASE_SECTION section))) \
PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name
#define DEFINE_PER_CPU(type, name) \
DEFINE_PER_CPU_SECTION(type, name, "")
#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \
DEFINE_PER_CPU_SECTION(type, name, PER_CPU_SHARED_ALIGNED_SECTION) \
____cacheline_aligned_in_smp
#define DEFINE_PER_CPU_PAGE_ALIGNED(type, name) \
DEFINE_PER_CPU_SECTION(type, name, ".page_aligned")
#define DEFINE_PER_CPU_FIRST(type, name) \
DEFINE_PER_CPU_SECTION(type, name, PER_CPU_FIRST_SECTION)
#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)
/* Enough to cover all DEFINE_PER_CPUs in kernel, including modules. */
#ifndef PERCPU_ENOUGH_ROOM
#ifdef CONFIG_MODULES
#define PERCPU_MODULE_RESERVE 8192
#else
#define PERCPU_MODULE_RESERVE 0
#endif
#define PERCPU_ENOUGH_ROOM \
(__per_cpu_end - __per_cpu_start + PERCPU_MODULE_RESERVE)
#endif /* PERCPU_ENOUGH_ROOM */
/*
* 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) (*({ \
extern int simple_identifier_##var(void); \
preempt_disable(); \
&__get_cpu_var(var); }))
#define put_cpu_var(var) preempt_enable()
#ifdef CONFIG_SMP
struct percpu_data {
void *ptrs[1];
};
#define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata)
/*
* 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) \
({ \
struct percpu_data *__p = __percpu_disguise(ptr); \
(__typeof__(ptr))__p->ptrs[(cpu)]; \
})
extern void *__alloc_percpu(size_t size, size_t align);
extern void free_percpu(void *__pdata);
#else /* CONFIG_SMP */
#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
static inline void *__alloc_percpu(size_t size, size_t align)
{
/*
* Can't easily make larger alignment work with kmalloc. WARN
* on it. Larger alignment should only be used for module
* percpu sections on SMP for which this path isn't used.
*/
WARN_ON_ONCE(align > __alignof__(unsigned long long));
return kzalloc(size, gfp);
}
static inline void free_percpu(void *p)
{
kfree(p);
}
#endif /* CONFIG_SMP */
#define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type), \
__alignof__(type))
#endif /* __LINUX_PERCPU_H */
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