1 #ifndef _ASM_IA64_ATOMIC_H 2 #define _ASM_IA64_ATOMIC_H 3 4 /* 5 * Atomic operations that C can't guarantee us. Useful for 6 * resource counting etc.. 7 * 8 * NOTE: don't mess with the types below! The "unsigned long" and 9 * "int" types were carefully placed so as to ensure proper operation 10 * of the macros. 11 * 12 * Copyright (C) 1998, 1999, 2002-2003 Hewlett-Packard Co 13 * David Mosberger-Tang <davidm@hpl.hp.com> 14 */ 15 #include <linux/types.h> 16 17 #include <asm/intrinsics.h> 18 #include <asm/system.h> 19 20 21 #define ATOMIC_INIT(i) ((atomic_t) { (i) }) 22 #define ATOMIC64_INIT(i) ((atomic64_t) { (i) }) 23 24 #define atomic_read(v) (*(volatile int *)&(v)->counter) 25 #define atomic64_read(v) (*(volatile long *)&(v)->counter) 26 27 #define atomic_set(v,i) (((v)->counter) = (i)) 28 #define atomic64_set(v,i) (((v)->counter) = (i)) 29 30 static __inline__ int 31 ia64_atomic_add (int i, atomic_t *v) 32 { 33 __s32 old, new; 34 CMPXCHG_BUGCHECK_DECL 35 36 do { 37 CMPXCHG_BUGCHECK(v); 38 old = atomic_read(v); 39 new = old + i; 40 } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic_t)) != old); 41 return new; 42 } 43 44 static __inline__ long 45 ia64_atomic64_add (__s64 i, atomic64_t *v) 46 { 47 __s64 old, new; 48 CMPXCHG_BUGCHECK_DECL 49 50 do { 51 CMPXCHG_BUGCHECK(v); 52 old = atomic64_read(v); 53 new = old + i; 54 } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic64_t)) != old); 55 return new; 56 } 57 58 static __inline__ int 59 ia64_atomic_sub (int i, atomic_t *v) 60 { 61 __s32 old, new; 62 CMPXCHG_BUGCHECK_DECL 63 64 do { 65 CMPXCHG_BUGCHECK(v); 66 old = atomic_read(v); 67 new = old - i; 68 } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic_t)) != old); 69 return new; 70 } 71 72 static __inline__ long 73 ia64_atomic64_sub (__s64 i, atomic64_t *v) 74 { 75 __s64 old, new; 76 CMPXCHG_BUGCHECK_DECL 77 78 do { 79 CMPXCHG_BUGCHECK(v); 80 old = atomic64_read(v); 81 new = old - i; 82 } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic64_t)) != old); 83 return new; 84 } 85 86 #define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new)) 87 #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) 88 89 #define atomic64_cmpxchg(v, old, new) \ 90 (cmpxchg(&((v)->counter), old, new)) 91 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new)) 92 93 static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u) 94 { 95 int c, old; 96 c = atomic_read(v); 97 for (;;) { 98 if (unlikely(c == (u))) 99 break; 100 old = atomic_cmpxchg((v), c, c + (a)); 101 if (likely(old == c)) 102 break; 103 c = old; 104 } 105 return c; 106 } 107 108 109 static __inline__ long atomic64_add_unless(atomic64_t *v, long a, long u) 110 { 111 long c, old; 112 c = atomic64_read(v); 113 for (;;) { 114 if (unlikely(c == (u))) 115 break; 116 old = atomic64_cmpxchg((v), c, c + (a)); 117 if (likely(old == c)) 118 break; 119 c = old; 120 } 121 return c != (u); 122 } 123 124 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0) 125 126 #define atomic_add_return(i,v) \ 127 ({ \ 128 int __ia64_aar_i = (i); \ 129 (__builtin_constant_p(i) \ 130 && ( (__ia64_aar_i == 1) || (__ia64_aar_i == 4) \ 131 || (__ia64_aar_i == 8) || (__ia64_aar_i == 16) \ 132 || (__ia64_aar_i == -1) || (__ia64_aar_i == -4) \ 133 || (__ia64_aar_i == -8) || (__ia64_aar_i == -16))) \ 134 ? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter) \ 135 : ia64_atomic_add(__ia64_aar_i, v); \ 136 }) 137 138 #define atomic64_add_return(i,v) \ 139 ({ \ 140 long __ia64_aar_i = (i); \ 141 (__builtin_constant_p(i) \ 142 && ( (__ia64_aar_i == 1) || (__ia64_aar_i == 4) \ 143 || (__ia64_aar_i == 8) || (__ia64_aar_i == 16) \ 144 || (__ia64_aar_i == -1) || (__ia64_aar_i == -4) \ 145 || (__ia64_aar_i == -8) || (__ia64_aar_i == -16))) \ 146 ? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter) \ 147 : ia64_atomic64_add(__ia64_aar_i, v); \ 148 }) 149 150 /* 151 * Atomically add I to V and return TRUE if the resulting value is 152 * negative. 153 */ 154 static __inline__ int 155 atomic_add_negative (int i, atomic_t *v) 156 { 157 return atomic_add_return(i, v) < 0; 158 } 159 160 static __inline__ long 161 atomic64_add_negative (__s64 i, atomic64_t *v) 162 { 163 return atomic64_add_return(i, v) < 0; 164 } 165 166 #define atomic_sub_return(i,v) \ 167 ({ \ 168 int __ia64_asr_i = (i); \ 169 (__builtin_constant_p(i) \ 170 && ( (__ia64_asr_i == 1) || (__ia64_asr_i == 4) \ 171 || (__ia64_asr_i == 8) || (__ia64_asr_i == 16) \ 172 || (__ia64_asr_i == -1) || (__ia64_asr_i == -4) \ 173 || (__ia64_asr_i == -8) || (__ia64_asr_i == -16))) \ 174 ? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter) \ 175 : ia64_atomic_sub(__ia64_asr_i, v); \ 176 }) 177 178 #define atomic64_sub_return(i,v) \ 179 ({ \ 180 long __ia64_asr_i = (i); \ 181 (__builtin_constant_p(i) \ 182 && ( (__ia64_asr_i == 1) || (__ia64_asr_i == 4) \ 183 || (__ia64_asr_i == 8) || (__ia64_asr_i == 16) \ 184 || (__ia64_asr_i == -1) || (__ia64_asr_i == -4) \ 185 || (__ia64_asr_i == -8) || (__ia64_asr_i == -16))) \ 186 ? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter) \ 187 : ia64_atomic64_sub(__ia64_asr_i, v); \ 188 }) 189 190 #define atomic_dec_return(v) atomic_sub_return(1, (v)) 191 #define atomic_inc_return(v) atomic_add_return(1, (v)) 192 #define atomic64_dec_return(v) atomic64_sub_return(1, (v)) 193 #define atomic64_inc_return(v) atomic64_add_return(1, (v)) 194 195 #define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0) 196 #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) 197 #define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0) 198 #define atomic64_sub_and_test(i,v) (atomic64_sub_return((i), (v)) == 0) 199 #define atomic64_dec_and_test(v) (atomic64_sub_return(1, (v)) == 0) 200 #define atomic64_inc_and_test(v) (atomic64_add_return(1, (v)) == 0) 201 202 #define atomic_add(i,v) atomic_add_return((i), (v)) 203 #define atomic_sub(i,v) atomic_sub_return((i), (v)) 204 #define atomic_inc(v) atomic_add(1, (v)) 205 #define atomic_dec(v) atomic_sub(1, (v)) 206 207 #define atomic64_add(i,v) atomic64_add_return((i), (v)) 208 #define atomic64_sub(i,v) atomic64_sub_return((i), (v)) 209 #define atomic64_inc(v) atomic64_add(1, (v)) 210 #define atomic64_dec(v) atomic64_sub(1, (v)) 211 212 /* Atomic operations are already serializing */ 213 #define smp_mb__before_atomic_dec() barrier() 214 #define smp_mb__after_atomic_dec() barrier() 215 #define smp_mb__before_atomic_inc() barrier() 216 #define smp_mb__after_atomic_inc() barrier() 217 218 #endif /* _ASM_IA64_ATOMIC_H */ 219