atomic.h 5.9 KB

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  1. #ifndef _ASM_IA64_ATOMIC_H
  2. #define _ASM_IA64_ATOMIC_H
  3. /*
  4. * Atomic operations that C can't guarantee us. Useful for
  5. * resource counting etc..
  6. *
  7. * NOTE: don't mess with the types below! The "unsigned long" and
  8. * "int" types were carefully placed so as to ensure proper operation
  9. * of the macros.
  10. *
  11. * Copyright (C) 1998, 1999, 2002-2003 Hewlett-Packard Co
  12. * David Mosberger-Tang <davidm@hpl.hp.com>
  13. */
  14. #include <linux/types.h>
  15. #include <asm/intrinsics.h>
  16. #define ATOMIC_INIT(i) { (i) }
  17. #define ATOMIC64_INIT(i) { (i) }
  18. #define atomic_read(v) (*(volatile int *)&(v)->counter)
  19. #define atomic64_read(v) (*(volatile long *)&(v)->counter)
  20. #define atomic_set(v,i) (((v)->counter) = (i))
  21. #define atomic64_set(v,i) (((v)->counter) = (i))
  22. static __inline__ int
  23. ia64_atomic_add (int i, atomic_t *v)
  24. {
  25. __s32 old, new;
  26. CMPXCHG_BUGCHECK_DECL
  27. do {
  28. CMPXCHG_BUGCHECK(v);
  29. old = atomic_read(v);
  30. new = old + i;
  31. } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic_t)) != old);
  32. return new;
  33. }
  34. static __inline__ long
  35. ia64_atomic64_add (__s64 i, atomic64_t *v)
  36. {
  37. __s64 old, new;
  38. CMPXCHG_BUGCHECK_DECL
  39. do {
  40. CMPXCHG_BUGCHECK(v);
  41. old = atomic64_read(v);
  42. new = old + i;
  43. } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic64_t)) != old);
  44. return new;
  45. }
  46. static __inline__ int
  47. ia64_atomic_sub (int i, atomic_t *v)
  48. {
  49. __s32 old, new;
  50. CMPXCHG_BUGCHECK_DECL
  51. do {
  52. CMPXCHG_BUGCHECK(v);
  53. old = atomic_read(v);
  54. new = old - i;
  55. } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic_t)) != old);
  56. return new;
  57. }
  58. static __inline__ long
  59. ia64_atomic64_sub (__s64 i, atomic64_t *v)
  60. {
  61. __s64 old, new;
  62. CMPXCHG_BUGCHECK_DECL
  63. do {
  64. CMPXCHG_BUGCHECK(v);
  65. old = atomic64_read(v);
  66. new = old - i;
  67. } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic64_t)) != old);
  68. return new;
  69. }
  70. #define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
  71. #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
  72. #define atomic64_cmpxchg(v, old, new) \
  73. (cmpxchg(&((v)->counter), old, new))
  74. #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
  75. static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
  76. {
  77. int c, old;
  78. c = atomic_read(v);
  79. for (;;) {
  80. if (unlikely(c == (u)))
  81. break;
  82. old = atomic_cmpxchg((v), c, c + (a));
  83. if (likely(old == c))
  84. break;
  85. c = old;
  86. }
  87. return c;
  88. }
  89. static __inline__ long atomic64_add_unless(atomic64_t *v, long a, long u)
  90. {
  91. long c, old;
  92. c = atomic64_read(v);
  93. for (;;) {
  94. if (unlikely(c == (u)))
  95. break;
  96. old = atomic64_cmpxchg((v), c, c + (a));
  97. if (likely(old == c))
  98. break;
  99. c = old;
  100. }
  101. return c != (u);
  102. }
  103. #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
  104. #define atomic_add_return(i,v) \
  105. ({ \
  106. int __ia64_aar_i = (i); \
  107. (__builtin_constant_p(i) \
  108. && ( (__ia64_aar_i == 1) || (__ia64_aar_i == 4) \
  109. || (__ia64_aar_i == 8) || (__ia64_aar_i == 16) \
  110. || (__ia64_aar_i == -1) || (__ia64_aar_i == -4) \
  111. || (__ia64_aar_i == -8) || (__ia64_aar_i == -16))) \
  112. ? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter) \
  113. : ia64_atomic_add(__ia64_aar_i, v); \
  114. })
  115. #define atomic64_add_return(i,v) \
  116. ({ \
  117. long __ia64_aar_i = (i); \
  118. (__builtin_constant_p(i) \
  119. && ( (__ia64_aar_i == 1) || (__ia64_aar_i == 4) \
  120. || (__ia64_aar_i == 8) || (__ia64_aar_i == 16) \
  121. || (__ia64_aar_i == -1) || (__ia64_aar_i == -4) \
  122. || (__ia64_aar_i == -8) || (__ia64_aar_i == -16))) \
  123. ? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter) \
  124. : ia64_atomic64_add(__ia64_aar_i, v); \
  125. })
  126. /*
  127. * Atomically add I to V and return TRUE if the resulting value is
  128. * negative.
  129. */
  130. static __inline__ int
  131. atomic_add_negative (int i, atomic_t *v)
  132. {
  133. return atomic_add_return(i, v) < 0;
  134. }
  135. static __inline__ long
  136. atomic64_add_negative (__s64 i, atomic64_t *v)
  137. {
  138. return atomic64_add_return(i, v) < 0;
  139. }
  140. #define atomic_sub_return(i,v) \
  141. ({ \
  142. int __ia64_asr_i = (i); \
  143. (__builtin_constant_p(i) \
  144. && ( (__ia64_asr_i == 1) || (__ia64_asr_i == 4) \
  145. || (__ia64_asr_i == 8) || (__ia64_asr_i == 16) \
  146. || (__ia64_asr_i == -1) || (__ia64_asr_i == -4) \
  147. || (__ia64_asr_i == -8) || (__ia64_asr_i == -16))) \
  148. ? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter) \
  149. : ia64_atomic_sub(__ia64_asr_i, v); \
  150. })
  151. #define atomic64_sub_return(i,v) \
  152. ({ \
  153. long __ia64_asr_i = (i); \
  154. (__builtin_constant_p(i) \
  155. && ( (__ia64_asr_i == 1) || (__ia64_asr_i == 4) \
  156. || (__ia64_asr_i == 8) || (__ia64_asr_i == 16) \
  157. || (__ia64_asr_i == -1) || (__ia64_asr_i == -4) \
  158. || (__ia64_asr_i == -8) || (__ia64_asr_i == -16))) \
  159. ? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter) \
  160. : ia64_atomic64_sub(__ia64_asr_i, v); \
  161. })
  162. #define atomic_dec_return(v) atomic_sub_return(1, (v))
  163. #define atomic_inc_return(v) atomic_add_return(1, (v))
  164. #define atomic64_dec_return(v) atomic64_sub_return(1, (v))
  165. #define atomic64_inc_return(v) atomic64_add_return(1, (v))
  166. #define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0)
  167. #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
  168. #define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0)
  169. #define atomic64_sub_and_test(i,v) (atomic64_sub_return((i), (v)) == 0)
  170. #define atomic64_dec_and_test(v) (atomic64_sub_return(1, (v)) == 0)
  171. #define atomic64_inc_and_test(v) (atomic64_add_return(1, (v)) == 0)
  172. #define atomic_add(i,v) atomic_add_return((i), (v))
  173. #define atomic_sub(i,v) atomic_sub_return((i), (v))
  174. #define atomic_inc(v) atomic_add(1, (v))
  175. #define atomic_dec(v) atomic_sub(1, (v))
  176. #define atomic64_add(i,v) atomic64_add_return((i), (v))
  177. #define atomic64_sub(i,v) atomic64_sub_return((i), (v))
  178. #define atomic64_inc(v) atomic64_add(1, (v))
  179. #define atomic64_dec(v) atomic64_sub(1, (v))
  180. /* Atomic operations are already serializing */
  181. #define smp_mb__before_atomic_dec() barrier()
  182. #define smp_mb__after_atomic_dec() barrier()
  183. #define smp_mb__before_atomic_inc() barrier()
  184. #define smp_mb__after_atomic_inc() barrier()
  185. #endif /* _ASM_IA64_ATOMIC_H */