#include <stdlib.h>

#include <unistd.h>

#define NR_CPUS 32

#define __section(S) __attribute__ ((__section__(#S)))

#define DEFINE_PER_CPU(type, name) \

__section(.data..percpu) __typeof__(type) name

#define per_cpu_offset(x) (__per_cpu_offset[x] - (unsigned long)&__per_cpu_start)

# define RELOC_HIDE(ptr, off) \

({ unsigned long __ptr; \

__ptr = (unsigned long) (ptr); \

(typeof(ptr)) (__ptr + (off)); })

#define SHIFT_PERCPU_PTR(__p, __offset) \

RELOC_HIDE((typeof(*(__p)) *)(__p), (__offset))

#define per_cpu_ptr(ptr, cpu) \

({ \

SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu))); \

})

#define raw_per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))

#define raw_cpu_write(ptr, cpu, val) \

({ \

*raw_per_cpu_ptr((ptr), cpu) = val; \

})

struct test_struct {

};

unsigned long __per_cpu_offset[NR_CPUS];

DEFINE_PER_CPU(struct test_struct, struct_test);

DEFINE_PER_CPU(unsigned long, ulong_test);

DEFINE_PER_CPU(void *, voidp_test);

DEFINE_PER_CPU(struct test_struct *, ptr_to_struct_test);

DEFINE_PER_CPU(unsigned long *, ptr_to_ulong_test);

extern unsigned long __per_cpu_start;

extern unsigned long __per_cpu_end;

extern unsigned long __per_cpu_load;

struct test_struct *percpu_test;

struct test_struct *non_percpu_test;

main(void)

{

int i;

unsigned long size = (void *)&__per_cpu_end - (void *)&__per_cpu_start;

for (i = 0; i < NR_CPUS; i++)

{

int ret;

struct test_struct *f;

void *ptr;

unsigned long *l;

ret = posix_memalign(&ptr, 4096, size);

if (ret)

return 1;

__per_cpu_offset[i] = (unsigned long)ptr;

f = per_cpu_ptr(&struct_test, i);

f->x = i;

f->ulong = i;

f->ptr = NULL;

raw_cpu_write(&ulong_test, i, i);

raw_cpu_write(&voidp_test, i, (void *)0xdeadbeef);

raw_cpu_write(&ptr_to_struct_test, i, f);

raw_cpu_write(&ptr_to_ulong_test, i, &f->ulong);

}

percpu_test = &struct_test;

non_percpu_test = per_cpu_ptr(&struct_test, 0);

/* We want to give gdb a core dump to work with */

abort();

return 0;

}