include/asm-cris/atomic.h

   1 /* $Id: atomic.h,v 1.3 2001/07/25 16:15:19 bjornw Exp $ */
   2
   3 #ifndef __ASM_CRIS_ATOMIC__
   4 #define __ASM_CRIS_ATOMIC__
   5
   6 #include <asm/system.h>
   7 #include <asm/arch/atomic.h>
   8
   9 /*
  10  * Atomic operations that C can't guarantee us.  Useful for
  11  * resource counting etc..
  12  */
  13
  14 typedef struct { volatile int counter; } atomic_t;
  15
  16 #define ATOMIC_INIT(i)  { (i) }
  17
  18 #define atomic_read(v) ((v)->counter)
  19 #define atomic_set(v,i) (((v)->counter) = (i))
  20
  21 /* These should be written in asm but we do it in C for now. */
  22
  23 extern __inline__ void atomic_add(int i, volatile atomic_t *v)
  24 {
  25         unsigned long flags;
  26         cris_atomic_save(v, flags);
  27         v->counter += i;
  28         cris_atomic_restore(v, flags);
  29 }
  30
  31 extern __inline__ void atomic_sub(int i, volatile atomic_t *v)
  32 {
  33         unsigned long flags;
  34         cris_atomic_save(v, flags);
  35         v->counter -= i;
  36         cris_atomic_restore(v, flags);
  37 }
  38
  39 extern __inline__ int atomic_add_return(int i, volatile atomic_t *v)
  40 {
  41         unsigned long flags;
  42         int retval;
  43         cris_atomic_save(v, flags);
  44         retval = (v->counter += i);
  45         cris_atomic_restore(v, flags);
  46         return retval;
  47 }
  48
  49 #define atomic_add_negative(a, v)       (atomic_add_return((a), (v)) < 0)
  50
  51 extern __inline__ int atomic_sub_return(int i, volatile atomic_t *v)
  52 {
  53         unsigned long flags;
  54         int retval;
  55         cris_atomic_save(v, flags);
  56         retval = (v->counter -= i);
  57         cris_atomic_restore(v, flags);
  58         return retval;
  59 }
  60
  61 extern __inline__ int atomic_sub_and_test(int i, volatile atomic_t *v)
  62 {
  63         int retval;
  64         unsigned long flags;
  65         cris_atomic_save(v, flags);
  66         retval = (v->counter -= i) == 0;
  67         cris_atomic_restore(v, flags);
  68         return retval;
  69 }
  70
  71 extern __inline__ void atomic_inc(volatile atomic_t *v)
  72 {
  73         unsigned long flags;
  74         cris_atomic_save(v, flags);
  75         (v->counter)++;
  76         cris_atomic_restore(v, flags);
  77 }
  78
  79 extern __inline__ void atomic_dec(volatile atomic_t *v)
  80 {
  81         unsigned long flags;
  82         cris_atomic_save(v, flags);
  83         (v->counter)--;
  84         cris_atomic_restore(v, flags);
  85 }
  86
  87 extern __inline__ int atomic_inc_return(volatile atomic_t *v)
  88 {
  89         unsigned long flags;
  90         int retval;
  91         cris_atomic_save(v, flags);
  92         retval = (v->counter)++;
  93         cris_atomic_restore(v, flags);
  94         return retval;
  95 }
  96
  97 extern __inline__ int atomic_dec_return(volatile atomic_t *v)
  98 {
  99         unsigned long flags;
 100         int retval;
 101         cris_atomic_save(v, flags);
 102         retval = (v->counter)--;
 103         cris_atomic_restore(v, flags);
 104         return retval;
 105 }
 106 extern __inline__ int atomic_dec_and_test(volatile atomic_t *v)
 107 {
 108         int retval;
 109         unsigned long flags;
 110         cris_atomic_save(v, flags);
 111         retval = --(v->counter) == 0;
 112         cris_atomic_restore(v, flags);
 113         return retval;
 114 }
 115
 116 extern __inline__ int atomic_inc_and_test(volatile atomic_t *v)
 117 {
 118         int retval;
 119         unsigned long flags;
 120         cris_atomic_save(v, flags);
 121         retval = ++(v->counter) == 0;
 122         cris_atomic_restore(v, flags);
 123         return retval;
 124 }
 125
 126 /* Atomic operations are already serializing */
 127 #define smp_mb__before_atomic_dec()    barrier()
 128 #define smp_mb__after_atomic_dec()     barrier()
 129 #define smp_mb__before_atomic_inc()    barrier()
 130 #define smp_mb__after_atomic_inc()     barrier()
 131
 132 #endif