Merge from Linus' tree
[linux-2.6] / include / asm-ia64 / percpu.h
1 #ifndef _ASM_IA64_PERCPU_H
2 #define _ASM_IA64_PERCPU_H
3
4 /*
5  * Copyright (C) 2002-2003 Hewlett-Packard Co
6  *      David Mosberger-Tang <davidm@hpl.hp.com>
7  */
8
9 #define PERCPU_ENOUGH_ROOM PERCPU_PAGE_SIZE
10
11 #ifdef __ASSEMBLY__
12 # define THIS_CPU(var)  (per_cpu__##var)  /* use this to mark accesses to per-CPU variables... */
13 #else /* !__ASSEMBLY__ */
14
15 #include <linux/config.h>
16
17 #include <linux/threads.h>
18
19 #ifdef HAVE_MODEL_SMALL_ATTRIBUTE
20 # define __SMALL_ADDR_AREA      __attribute__((__model__ (__small__)))
21 #else
22 # define __SMALL_ADDR_AREA
23 #endif
24
25 #define DECLARE_PER_CPU(type, name)                             \
26         extern __SMALL_ADDR_AREA __typeof__(type) per_cpu__##name
27
28 /* Separate out the type, so (int[3], foo) works. */
29 #define DEFINE_PER_CPU(type, name)                              \
30         __attribute__((__section__(".data.percpu")))            \
31         __SMALL_ADDR_AREA __typeof__(type) per_cpu__##name
32
33 /*
34  * Pretty much a literal copy of asm-generic/percpu.h, except that percpu_modcopy() is an
35  * external routine, to avoid include-hell.
36  */
37 #ifdef CONFIG_SMP
38
39 extern unsigned long __per_cpu_offset[NR_CPUS];
40
41 /* Equal to __per_cpu_offset[smp_processor_id()], but faster to access: */
42 DECLARE_PER_CPU(unsigned long, local_per_cpu_offset);
43
44 #define per_cpu(var, cpu)  (*RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]))
45 #define __get_cpu_var(var) (*RELOC_HIDE(&per_cpu__##var, __ia64_per_cpu_var(local_per_cpu_offset)))
46
47 extern void percpu_modcopy(void *pcpudst, const void *src, unsigned long size);
48 extern void setup_per_cpu_areas (void);
49 extern void *per_cpu_init(void);
50
51 #else /* ! SMP */
52
53 #define per_cpu(var, cpu)                       (*((void)(cpu), &per_cpu__##var))
54 #define __get_cpu_var(var)                      per_cpu__##var
55 #define per_cpu_init()                          (__phys_per_cpu_start)
56
57 #endif  /* SMP */
58
59 #define EXPORT_PER_CPU_SYMBOL(var)              EXPORT_SYMBOL(per_cpu__##var)
60 #define EXPORT_PER_CPU_SYMBOL_GPL(var)          EXPORT_SYMBOL_GPL(per_cpu__##var)
61
62 /*
63  * Be extremely careful when taking the address of this variable!  Due to virtual
64  * remapping, it is different from the canonical address returned by __get_cpu_var(var)!
65  * On the positive side, using __ia64_per_cpu_var() instead of __get_cpu_var() is slightly
66  * more efficient.
67  */
68 #define __ia64_per_cpu_var(var) (per_cpu__##var)
69
70 #endif /* !__ASSEMBLY__ */
71
72 #endif /* _ASM_IA64_PERCPU_H */