1 /* atomic.h: Thankfully the V9 is at least reasonable for this 2 * stuff. 3 * 4 * Copyright (C) 1996, 1997, 2000 David S. Miller (davem@redhat.com) 5 */ 6 7 #ifndef __ARCH_SPARC64_ATOMIC__ 8 #define __ARCH_SPARC64_ATOMIC__ 9 10 #include <linux/types.h> 11 #include <asm/system.h> 12 13 typedef struct { volatile int counter; } atomic_t; 14 typedef struct { volatile __s64 counter; } atomic64_t; 15 16 #define ATOMIC_INIT(i) { (i) } 17 #define ATOMIC64_INIT(i) { (i) } 18 19 #define atomic_read(v) ((v)->counter) 20 #define atomic64_read(v) ((v)->counter) 21 22 #define atomic_set(v, i) (((v)->counter) = i) 23 #define atomic64_set(v, i) (((v)->counter) = i) 24 25 extern void atomic_add(int, atomic_t *); 26 extern void atomic64_add(int, atomic64_t *); 27 extern void atomic_sub(int, atomic_t *); 28 extern void atomic64_sub(int, atomic64_t *); 29 30 extern int atomic_add_ret(int, atomic_t *); 31 extern int atomic64_add_ret(int, atomic64_t *); 32 extern int atomic_sub_ret(int, atomic_t *); 33 extern int atomic64_sub_ret(int, atomic64_t *); 34 35 #define atomic_dec_return(v) atomic_sub_ret(1, v) 36 #define atomic64_dec_return(v) atomic64_sub_ret(1, v) 37 38 #define atomic_inc_return(v) atomic_add_ret(1, v) 39 #define atomic64_inc_return(v) atomic64_add_ret(1, v) 40 41 #define atomic_sub_return(i, v) atomic_sub_ret(i, v) 42 #define atomic64_sub_return(i, v) atomic64_sub_ret(i, v) 43 44 #define atomic_add_return(i, v) atomic_add_ret(i, v) 45 #define atomic64_add_return(i, v) atomic64_add_ret(i, v) 46 47 /* 48 * atomic_inc_and_test - increment and test 49 * @v: pointer of type atomic_t 50 * 51 * Atomically increments @v by 1 52 * and returns true if the result is zero, or false for all 53 * other cases. 54 */ 55 #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) 56 #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0) 57 58 #define atomic_sub_and_test(i, v) (atomic_sub_ret(i, v) == 0) 59 #define atomic64_sub_and_test(i, v) (atomic64_sub_ret(i, v) == 0) 60 61 #define atomic_dec_and_test(v) (atomic_sub_ret(1, v) == 0) 62 #define atomic64_dec_and_test(v) (atomic64_sub_ret(1, v) == 0) 63 64 #define atomic_inc(v) atomic_add(1, v) 65 #define atomic64_inc(v) atomic64_add(1, v) 66 67 #define atomic_dec(v) atomic_sub(1, v) 68 #define atomic64_dec(v) atomic64_sub(1, v) 69 70 #define atomic_add_negative(i, v) (atomic_add_ret(i, v) < 0) 71 #define atomic64_add_negative(i, v) (atomic64_add_ret(i, v) < 0) 72 73 #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n))) 74 #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) 75 76 static inline int atomic_add_unless(atomic_t *v, int a, int u) 77 { 78 int c, old; 79 c = atomic_read(v); 80 for (;;) { 81 if (unlikely(c == (u))) 82 break; 83 old = atomic_cmpxchg((v), c, c + (a)); 84 if (likely(old == c)) 85 break; 86 c = old; 87 } 88 return c != (u); 89 } 90 91 #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) 92 93 #define atomic64_cmpxchg(v, o, n) \ 94 ((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n))) 95 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new)) 96 97 static inline int atomic64_add_unless(atomic64_t *v, long a, long u) 98 { 99 long c, old; 100 c = atomic64_read(v); 101 for (;;) { 102 if (unlikely(c == (u))) 103 break; 104 old = atomic64_cmpxchg((v), c, c + (a)); 105 if (likely(old == c)) 106 break; 107 c = old; 108 } 109 return c != (u); 110 } 111 112 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0) 113 114 /* Atomic operations are already serializing */ 115 #ifdef CONFIG_SMP 116 #define smp_mb__before_atomic_dec() membar_storeload_loadload(); 117 #define smp_mb__after_atomic_dec() membar_storeload_storestore(); 118 #define smp_mb__before_atomic_inc() membar_storeload_loadload(); 119 #define smp_mb__after_atomic_inc() membar_storeload_storestore(); 120 #else 121 #define smp_mb__before_atomic_dec() barrier() 122 #define smp_mb__after_atomic_dec() barrier() 123 #define smp_mb__before_atomic_inc() barrier() 124 #define smp_mb__after_atomic_inc() barrier() 125 #endif 126 127 #include <asm-generic/atomic.h> 128 #endif /* !(__ARCH_SPARC64_ATOMIC__) */ 129