arch/sparc64/lib/atomic.S

   1 /* atomic.S: These things are too big to do inline.
   2  *
   3  * Copyright (C) 1999, 2007 David S. Miller (davem@davemloft.net)
   4  */
   5
   6 #include <asm/asi.h>
   7 #include <asm/backoff.h>
   8
   9         .text
  10
  11         /* Two versions of the atomic routines, one that
  12          * does not return a value and does not perform
  13          * memory barriers, and a second which returns
  14          * a value and does the barriers.
  15          */
  16         .globl  atomic_add
  17         .type   atomic_add,#function
  18 atomic_add: /* %o0 = increment, %o1 = atomic_ptr */
  19         BACKOFF_SETUP(%o2)
  20 1:      lduw    [%o1], %g1
  21         add     %g1, %o0, %g7
  22         cas     [%o1], %g1, %g7
  23         cmp     %g1, %g7
  24         bne,pn  %icc, 2f
  25          nop
  26         retl
  27          nop
  28 2:      BACKOFF_SPIN(%o2, %o3, 1b)
  29         .size   atomic_add, .-atomic_add
  30
  31         .globl  atomic_sub
  32         .type   atomic_sub,#function
  33 atomic_sub: /* %o0 = decrement, %o1 = atomic_ptr */
  34         BACKOFF_SETUP(%o2)
  35 1:      lduw    [%o1], %g1
  36         sub     %g1, %o0, %g7
  37         cas     [%o1], %g1, %g7
  38         cmp     %g1, %g7
  39         bne,pn  %icc, 2f
  40          nop
  41         retl
  42          nop
  43 2:      BACKOFF_SPIN(%o2, %o3, 1b)
  44         .size   atomic_sub, .-atomic_sub
  45
  46         .globl  atomic_add_ret
  47         .type   atomic_add_ret,#function
  48 atomic_add_ret: /* %o0 = increment, %o1 = atomic_ptr */
  49         BACKOFF_SETUP(%o2)
  50 1:      lduw    [%o1], %g1
  51         add     %g1, %o0, %g7
  52         cas     [%o1], %g1, %g7
  53         cmp     %g1, %g7
  54         bne,pn  %icc, 2f
  55          add    %g7, %o0, %g7
  56         sra     %g7, 0, %o0
  57         retl
  58          nop
  59 2:      BACKOFF_SPIN(%o2, %o3, 1b)
  60         .size   atomic_add_ret, .-atomic_add_ret
  61
  62         .globl  atomic_sub_ret
  63         .type   atomic_sub_ret,#function
  64 atomic_sub_ret: /* %o0 = decrement, %o1 = atomic_ptr */
  65         BACKOFF_SETUP(%o2)
  66 1:      lduw    [%o1], %g1
  67         sub     %g1, %o0, %g7
  68         cas     [%o1], %g1, %g7
  69         cmp     %g1, %g7
  70         bne,pn  %icc, 2f
  71          sub    %g7, %o0, %g7
  72         sra     %g7, 0, %o0
  73         retl
  74          nop
  75 2:      BACKOFF_SPIN(%o2, %o3, 1b)
  76         .size   atomic_sub_ret, .-atomic_sub_ret
  77
  78         .globl  atomic64_add
  79         .type   atomic64_add,#function
  80 atomic64_add: /* %o0 = increment, %o1 = atomic_ptr */
  81         BACKOFF_SETUP(%o2)
  82 1:      ldx     [%o1], %g1
  83         add     %g1, %o0, %g7
  84         casx    [%o1], %g1, %g7
  85         cmp     %g1, %g7
  86         bne,pn  %xcc, 2f
  87          nop
  88         retl
  89          nop
  90 2:      BACKOFF_SPIN(%o2, %o3, 1b)
  91         .size   atomic64_add, .-atomic64_add
  92
  93         .globl  atomic64_sub
  94         .type   atomic64_sub,#function
  95 atomic64_sub: /* %o0 = decrement, %o1 = atomic_ptr */
  96         BACKOFF_SETUP(%o2)
  97 1:      ldx     [%o1], %g1
  98         sub     %g1, %o0, %g7
  99         casx    [%o1], %g1, %g7
 100         cmp     %g1, %g7
 101         bne,pn  %xcc, 2f
 102          nop
 103         retl
 104          nop
 105 2:      BACKOFF_SPIN(%o2, %o3, 1b)
 106         .size   atomic64_sub, .-atomic64_sub
 107
 108         .globl  atomic64_add_ret
 109         .type   atomic64_add_ret,#function
 110 atomic64_add_ret: /* %o0 = increment, %o1 = atomic_ptr */
 111         BACKOFF_SETUP(%o2)
 112 1:      ldx     [%o1], %g1
 113         add     %g1, %o0, %g7
 114         casx    [%o1], %g1, %g7
 115         cmp     %g1, %g7
 116         bne,pn  %xcc, 2f
 117          add    %g7, %o0, %g7
 118         mov     %g7, %o0
 119         retl
 120          nop
 121 2:      BACKOFF_SPIN(%o2, %o3, 1b)
 122         .size   atomic64_add_ret, .-atomic64_add_ret
 123
 124         .globl  atomic64_sub_ret
 125         .type   atomic64_sub_ret,#function
 126 atomic64_sub_ret: /* %o0 = decrement, %o1 = atomic_ptr */
 127         BACKOFF_SETUP(%o2)
 128 1:      ldx     [%o1], %g1
 129         sub     %g1, %o0, %g7
 130         casx    [%o1], %g1, %g7
 131         cmp     %g1, %g7
 132         bne,pn  %xcc, 2f
 133          sub    %g7, %o0, %g7
 134         mov     %g7, %o0
 135         retl
 136          nop
 137 2:      BACKOFF_SPIN(%o2, %o3, 1b)
 138         .size   atomic64_sub_ret, .-atomic64_sub_ret