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 */