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 * On IA-64, counter must always be volatile to ensure that that the 22 * memory accesses are ordered. 23 */ 24typedef struct { volatile __s32 counter; } atomic_t; 25typedef struct { volatile __s64 counter; } atomic64_t; 26 27#define ATOMIC_INIT(i) ((atomic_t) { (i) }) 28#define ATOMIC64_INIT(i) ((atomic64_t) { (i) }) 29 30#define atomic_read(v) ((v)->counter) 31#define atomic64_read(v) ((v)->counter) 32 33#define atomic_set(v,i) (((v)->counter) = (i)) 34#define atomic64_set(v,i) (((v)->counter) = (i)) 35 36static __inline__ int 37ia64_atomic_add (int i, atomic_t *v) 38{ 39 __s32 old, new; 40 CMPXCHG_BUGCHECK_DECL 41 42 do { 43 CMPXCHG_BUGCHECK(v); 44 old = atomic_read(v); 45 new = old + i; 46 } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic_t)) != old); 47 return new; 48} 49 50static __inline__ int 51ia64_atomic64_add (__s64 i, atomic64_t *v) 52{ 53 __s64 old, new; 54 CMPXCHG_BUGCHECK_DECL 55 56 do { 57 CMPXCHG_BUGCHECK(v); 58 old = atomic_read(v); 59 new = old + i; 60 } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic64_t)) != old); 61 return new; 62} 63 64static __inline__ int 65ia64_atomic_sub (int i, atomic_t *v) 66{ 67 __s32 old, new; 68 CMPXCHG_BUGCHECK_DECL 69 70 do { 71 CMPXCHG_BUGCHECK(v); 72 old = atomic_read(v); 73 new = old - i; 74 } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic_t)) != old); 75 return new; 76} 77 78static __inline__ int 79ia64_atomic64_sub (__s64 i, atomic64_t *v) 80{ 81 __s64 old, new; 82 CMPXCHG_BUGCHECK_DECL 83 84 do { 85 CMPXCHG_BUGCHECK(v); 86 old = atomic_read(v); 87 new = old - i; 88 } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic64_t)) != old); 89 return new; 90} 91 92#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new)) 93#define atomic_xchg(v, new) (xchg(&((v)->counter), new)) 94 95#define atomic64_cmpxchg(v, old, new) \ 96 (cmpxchg(&((v)->counter), old, new)) 97#define atomic64_xchg(v, new) (xchg(&((v)->counter), new)) 98 99static __inline__ int atomic_add_unless(atomic_t *v, int a, int u) 100{ 101 int c, old; 102 c = atomic_read(v); 103 for (;;) { 104 if (unlikely(c == (u))) 105 break; 106 old = atomic_cmpxchg((v), c, c + (a)); 107 if (likely(old == c)) 108 break; 109 c = old; 110 } 111 return c != (u); 112} 113 114#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) 115 116static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u) 117{ 118 long c, old; 119 c = atomic64_read(v); 120 for (;;) { 121 if (unlikely(c == (u))) 122 break; 123 old = atomic64_cmpxchg((v), c, c + (a)); 124 if (likely(old == c)) 125 break; 126 c = old; 127 } 128 return c != (u); 129} 130 131#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0) 132 133#define atomic_add_return(i,v) \ 134({ \ 135 int __ia64_aar_i = (i); \ 136 (__builtin_constant_p(i) \ 137 && ( (__ia64_aar_i == 1) || (__ia64_aar_i == 4) \ 138 || (__ia64_aar_i == 8) || (__ia64_aar_i == 16) \ 139 || (__ia64_aar_i == -1) || (__ia64_aar_i == -4) \ 140 || (__ia64_aar_i == -8) || (__ia64_aar_i == -16))) \ 141 ? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter) \ 142 : ia64_atomic_add(__ia64_aar_i, v); \ 143}) 144 145#define atomic64_add_return(i,v) \ 146({ \ 147 long __ia64_aar_i = (i); \ 148 (__builtin_constant_p(i) \ 149 && ( (__ia64_aar_i == 1) || (__ia64_aar_i == 4) \ 150 || (__ia64_aar_i == 8) || (__ia64_aar_i == 16) \ 151 || (__ia64_aar_i == -1) || (__ia64_aar_i == -4) \ 152 || (__ia64_aar_i == -8) || (__ia64_aar_i == -16))) \ 153 ? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter) \ 154 : ia64_atomic64_add(__ia64_aar_i, v); \ 155}) 156 157/* 158 * Atomically add I to V and return TRUE if the resulting value is 159 * negative. 160 */ 161static __inline__ int 162atomic_add_negative (int i, atomic_t *v) 163{ 164 return atomic_add_return(i, v) < 0; 165} 166 167static __inline__ int 168atomic64_add_negative (__s64 i, atomic64_t *v) 169{ 170 return atomic64_add_return(i, v) < 0; 171} 172 173#define atomic_sub_return(i,v) \ 174({ \ 175 int __ia64_asr_i = (i); \ 176 (__builtin_constant_p(i) \ 177 && ( (__ia64_asr_i == 1) || (__ia64_asr_i == 4) \ 178 || (__ia64_asr_i == 8) || (__ia64_asr_i == 16) \ 179 || (__ia64_asr_i == -1) || (__ia64_asr_i == -4) \ 180 || (__ia64_asr_i == -8) || (__ia64_asr_i == -16))) \ 181 ? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter) \ 182 : ia64_atomic_sub(__ia64_asr_i, v); \ 183}) 184 185#define atomic64_sub_return(i,v) \ 186({ \ 187 long __ia64_asr_i = (i); \ 188 (__builtin_constant_p(i) \ 189 && ( (__ia64_asr_i == 1) || (__ia64_asr_i == 4) \ 190 || (__ia64_asr_i == 8) || (__ia64_asr_i == 16) \ 191 || (__ia64_asr_i == -1) || (__ia64_asr_i == -4) \ 192 || (__ia64_asr_i == -8) || (__ia64_asr_i == -16))) \ 193 ? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter) \ 194 : ia64_atomic64_sub(__ia64_asr_i, v); \ 195}) 196 197#define atomic_dec_return(v) atomic_sub_return(1, (v)) 198#define atomic_inc_return(v) atomic_add_return(1, (v)) 199#define atomic64_dec_return(v) atomic64_sub_return(1, (v)) 200#define atomic64_inc_return(v) atomic64_add_return(1, (v)) 201 202#define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0) 203#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) 204#define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0) 205#define atomic64_sub_and_test(i,v) (atomic64_sub_return((i), (v)) == 0) 206#define atomic64_dec_and_test(v) (atomic64_sub_return(1, (v)) == 0) 207#define atomic64_inc_and_test(v) (atomic64_add_return(1, (v)) == 0) 208 209#define atomic_add(i,v) atomic_add_return((i), (v)) 210#define atomic_sub(i,v) atomic_sub_return((i), (v)) 211#define atomic_inc(v) atomic_add(1, (v)) 212#define atomic_dec(v) atomic_sub(1, (v)) 213 214#define atomic64_add(i,v) atomic64_add_return((i), (v)) 215#define atomic64_sub(i,v) atomic64_sub_return((i), (v)) 216#define atomic64_inc(v) atomic64_add(1, (v)) 217#define atomic64_dec(v) atomic64_sub(1, (v)) 218 219/* Atomic operations are already serializing */ 220#define smp_mb__before_atomic_dec() barrier() 221#define smp_mb__after_atomic_dec() barrier() 222#define smp_mb__before_atomic_inc() barrier() 223#define smp_mb__after_atomic_inc() barrier() 224 225#include <asm-generic/atomic.h> 226#endif /* _ASM_IA64_ATOMIC_H */ 227