include/asm-s390/percpu.h

   1 #ifndef __ARCH_S390_PERCPU__
   2 #define __ARCH_S390_PERCPU__
   3
   4 #include <linux/compiler.h>
   5 #include <asm/lowcore.h>
   6
   7 #define __GENERIC_PER_CPU
   8
   9 /*
  10  * s390 uses its own implementation for per cpu data, the offset of
  11  * the cpu local data area is cached in the cpu's lowcore memory.
  12  * For 64 bit module code s390 forces the use of a GOT slot for the
  13  * address of the per cpu variable. This is needed because the module
  14  * may be more than 4G above the per cpu area.
  15  */
  16 #if defined(__s390x__) && defined(MODULE)
  17
  18 #define __reloc_hide(var,offset) (*({                   \
  19         extern int simple_identifier_##var(void);       \
  20         unsigned long *__ptr;                           \
  21         asm ( "larl %0,per_cpu__"#var"@GOTENT"          \
  22             : "=a" (__ptr) : "X" (per_cpu__##var) );    \
  23         (typeof(&per_cpu__##var))((*__ptr) + (offset)); }))
  24
  25 #else
  26
  27 #define __reloc_hide(var, offset) (*({                          \
  28         extern int simple_identifier_##var(void);               \
  29         unsigned long __ptr;                                    \
  30         asm ( "" : "=a" (__ptr) : "0" (&per_cpu__##var) );      \
  31         (typeof(&per_cpu__##var)) (__ptr + (offset)); }))
  32
  33 #endif
  34
  35 #ifdef CONFIG_SMP
  36
  37 extern unsigned long __per_cpu_offset[NR_CPUS];
  38
  39 /* Separate out the type, so (int[3], foo) works. */
  40 #define DEFINE_PER_CPU(type, name) \
  41     __attribute__((__section__(".data.percpu"))) \
  42     __typeof__(type) per_cpu__##name
  43
  44 #define __get_cpu_var(var) __reloc_hide(var,S390_lowcore.percpu_offset)
  45 #define __raw_get_cpu_var(var) __reloc_hide(var,S390_lowcore.percpu_offset)
  46 #define per_cpu(var,cpu) __reloc_hide(var,__per_cpu_offset[cpu])
  47 #define per_cpu_offset(x) (__per_cpu_offset[x])
  48
  49 /* A macro to avoid #include hell... */
  50 #define percpu_modcopy(pcpudst, src, size)                      \
  51 do {                                                            \
  52         unsigned int __i;                                       \
  53         for_each_possible_cpu(__i)                              \
  54                 memcpy((pcpudst)+__per_cpu_offset[__i],         \
  55                        (src), (size));                          \
  56 } while (0)
  57
  58 #else /* ! SMP */
  59
  60 #define DEFINE_PER_CPU(type, name) \
  61     __typeof__(type) per_cpu__##name
  62
  63 #define __get_cpu_var(var) __reloc_hide(var,0)
  64 #define __raw_get_cpu_var(var) __reloc_hide(var,0)
  65 #define per_cpu(var,cpu) __reloc_hide(var,0)
  66
  67 #endif /* SMP */
  68
  69 #define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu__##name
  70
  71 #define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
  72 #define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)
  73
  74 #endif /* __ARCH_S390_PERCPU__ */