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
  16 #include <linux/threads.h>
  17
  18 #ifdef HAVE_MODEL_SMALL_ATTRIBUTE
  19 # define __SMALL_ADDR_AREA      __attribute__((__model__ (__small__)))
  20 #else
  21 # define __SMALL_ADDR_AREA
  22 #endif
  23
  24 #define DECLARE_PER_CPU(type, name)                             \
  25         extern __SMALL_ADDR_AREA __typeof__(type) per_cpu__##name
  26
  27 /* Separate out the type, so (int[3], foo) works. */
  28 #define DEFINE_PER_CPU(type, name)                              \
  29         __attribute__((__section__(".data.percpu")))            \
  30         __SMALL_ADDR_AREA __typeof__(type) per_cpu__##name
  31
  32 /*
  33  * Pretty much a literal copy of asm-generic/percpu.h, except that percpu_modcopy() is an
  34  * external routine, to avoid include-hell.
  35  */
  36 #ifdef CONFIG_SMP
  37
  38 extern unsigned long __per_cpu_offset[NR_CPUS];
  39
  40 /* Equal to __per_cpu_offset[smp_processor_id()], but faster to access: */
  41 DECLARE_PER_CPU(unsigned long, local_per_cpu_offset);
  42
  43 #define per_cpu(var, cpu)  (*RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]))
  44 #define __get_cpu_var(var) (*RELOC_HIDE(&per_cpu__##var, __ia64_per_cpu_var(local_per_cpu_offset)))
  45
  46 extern void percpu_modcopy(void *pcpudst, const void *src, unsigned long size);
  47 extern void setup_per_cpu_areas (void);
  48 extern void *per_cpu_init(void);
  49
  50 #else /* ! SMP */
  51
  52 #define per_cpu(var, cpu)                       (*((void)(cpu), &per_cpu__##var))
  53 #define __get_cpu_var(var)                      per_cpu__##var
  54 #define per_cpu_init()                          (__phys_per_cpu_start)
  55
  56 #endif  /* SMP */
  57
  58 #define EXPORT_PER_CPU_SYMBOL(var)              EXPORT_SYMBOL(per_cpu__##var)
  59 #define EXPORT_PER_CPU_SYMBOL_GPL(var)          EXPORT_SYMBOL_GPL(per_cpu__##var)
  60
  61 /*
  62  * Be extremely careful when taking the address of this variable!  Due to virtual
  63  * remapping, it is different from the canonical address returned by __get_cpu_var(var)!
  64  * On the positive side, using __ia64_per_cpu_var() instead of __get_cpu_var() is slightly
  65  * more efficient.
  66  */
  67 #define __ia64_per_cpu_var(var) (per_cpu__##var)
  68
  69 #endif /* !__ASSEMBLY__ */
  70
  71 #endif /* _ASM_IA64_PERCPU_H */