1 /* atomic.h: Thankfully the V9 is at least reasonable for this 2 * stuff. 3 * 4 * Copyright (C) 1996, 1997, 2000, 2012 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/cmpxchg.h> 12 #include <asm/barrier.h> 13 14 #define ATOMIC_INIT(i) { (i) } 15 #define ATOMIC64_INIT(i) { (i) } 16 17 #define atomic_read(v) READ_ONCE((v)->counter) 18 #define atomic64_read(v) READ_ONCE((v)->counter) 19 20 #define atomic_set(v, i) WRITE_ONCE(((v)->counter), (i)) 21 #define atomic64_set(v, i) WRITE_ONCE(((v)->counter), (i)) 22 23 #define ATOMIC_OP(op) \ 24 void atomic_##op(int, atomic_t *); \ 25 void atomic64_##op(long, atomic64_t *); 26 27 #define ATOMIC_OP_RETURN(op) \ 28 int atomic_##op##_return(int, atomic_t *); \ 29 long atomic64_##op##_return(long, atomic64_t *); 30 31 #define ATOMIC_FETCH_OP(op) \ 32 int atomic_fetch_##op(int, atomic_t *); \ 33 long atomic64_fetch_##op(long, atomic64_t *); 34 35 #define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op) 36 37 ATOMIC_OPS(add) 38 ATOMIC_OPS(sub) 39 40 #undef ATOMIC_OPS 41 #define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op) 42 43 ATOMIC_OPS(and) 44 ATOMIC_OPS(or) 45 ATOMIC_OPS(xor) 46 47 #undef ATOMIC_OPS 48 #undef ATOMIC_FETCH_OP 49 #undef ATOMIC_OP_RETURN 50 #undef ATOMIC_OP 51 52 #define atomic_dec_return(v) atomic_sub_return(1, v) 53 #define atomic64_dec_return(v) atomic64_sub_return(1, v) 54 55 #define atomic_inc_return(v) atomic_add_return(1, v) 56 #define atomic64_inc_return(v) atomic64_add_return(1, v) 57 58 /* 59 * atomic_inc_and_test - increment and test 60 * @v: pointer of type atomic_t 61 * 62 * Atomically increments @v by 1 63 * and returns true if the result is zero, or false for all 64 * other cases. 65 */ 66 #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) 67 #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0) 68 69 #define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0) 70 #define atomic64_sub_and_test(i, v) (atomic64_sub_return(i, v) == 0) 71 72 #define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0) 73 #define atomic64_dec_and_test(v) (atomic64_sub_return(1, v) == 0) 74 75 #define atomic_inc(v) atomic_add(1, v) 76 #define atomic64_inc(v) atomic64_add(1, v) 77 78 #define atomic_dec(v) atomic_sub(1, v) 79 #define atomic64_dec(v) atomic64_sub(1, v) 80 81 #define atomic_add_negative(i, v) (atomic_add_return(i, v) < 0) 82 #define atomic64_add_negative(i, v) (atomic64_add_return(i, v) < 0) 83 84 #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n))) 85 #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) 86 87 static inline int __atomic_add_unless(atomic_t *v, int a, int u) 88 { 89 int c, old; 90 c = atomic_read(v); 91 for (;;) { 92 if (unlikely(c == (u))) 93 break; 94 old = atomic_cmpxchg((v), c, c + (a)); 95 if (likely(old == c)) 96 break; 97 c = old; 98 } 99 return c; 100 } 101 102 #define atomic64_cmpxchg(v, o, n) \ 103 ((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n))) 104 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new)) 105 106 static inline long atomic64_add_unless(atomic64_t *v, long a, long u) 107 { 108 long c, old; 109 c = atomic64_read(v); 110 for (;;) { 111 if (unlikely(c == (u))) 112 break; 113 old = atomic64_cmpxchg((v), c, c + (a)); 114 if (likely(old == c)) 115 break; 116 c = old; 117 } 118 return c != (u); 119 } 120 121 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0) 122 123 long atomic64_dec_if_positive(atomic64_t *v); 124 125 #endif /* !(__ARCH_SPARC64_ATOMIC__) */ 126