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) (*(volatile int *)&(v)->counter) 18 #define atomic64_read(v) (*(volatile long *)&(v)->counter) 19 20 #define atomic_set(v, i) (((v)->counter) = i) 21 #define atomic64_set(v, i) (((v)->counter) = i) 22 23 extern void atomic_add(int, atomic_t *); 24 extern void atomic64_add(long, atomic64_t *); 25 extern void atomic_sub(int, atomic_t *); 26 extern void atomic64_sub(long, atomic64_t *); 27 28 extern int atomic_add_ret(int, atomic_t *); 29 extern long atomic64_add_ret(long, atomic64_t *); 30 extern int atomic_sub_ret(int, atomic_t *); 31 extern long atomic64_sub_ret(long, atomic64_t *); 32 33 #define atomic_dec_return(v) atomic_sub_ret(1, v) 34 #define atomic64_dec_return(v) atomic64_sub_ret(1, v) 35 36 #define atomic_inc_return(v) atomic_add_ret(1, v) 37 #define atomic64_inc_return(v) atomic64_add_ret(1, v) 38 39 #define atomic_sub_return(i, v) atomic_sub_ret(i, v) 40 #define atomic64_sub_return(i, v) atomic64_sub_ret(i, v) 41 42 #define atomic_add_return(i, v) atomic_add_ret(i, v) 43 #define atomic64_add_return(i, v) atomic64_add_ret(i, v) 44 45 /* 46 * atomic_inc_and_test - increment and test 47 * @v: pointer of type atomic_t 48 * 49 * Atomically increments @v by 1 50 * and returns true if the result is zero, or false for all 51 * other cases. 52 */ 53 #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) 54 #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0) 55 56 #define atomic_sub_and_test(i, v) (atomic_sub_ret(i, v) == 0) 57 #define atomic64_sub_and_test(i, v) (atomic64_sub_ret(i, v) == 0) 58 59 #define atomic_dec_and_test(v) (atomic_sub_ret(1, v) == 0) 60 #define atomic64_dec_and_test(v) (atomic64_sub_ret(1, v) == 0) 61 62 #define atomic_inc(v) atomic_add(1, v) 63 #define atomic64_inc(v) atomic64_add(1, v) 64 65 #define atomic_dec(v) atomic_sub(1, v) 66 #define atomic64_dec(v) atomic64_sub(1, v) 67 68 #define atomic_add_negative(i, v) (atomic_add_ret(i, v) < 0) 69 #define atomic64_add_negative(i, v) (atomic64_add_ret(i, v) < 0) 70 71 #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n))) 72 #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) 73 74 static inline int __atomic_add_unless(atomic_t *v, int a, int u) 75 { 76 int c, old; 77 c = atomic_read(v); 78 for (;;) { 79 if (unlikely(c == (u))) 80 break; 81 old = atomic_cmpxchg((v), c, c + (a)); 82 if (likely(old == c)) 83 break; 84 c = old; 85 } 86 return c; 87 } 88 89 #define atomic64_cmpxchg(v, o, n) \ 90 ((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n))) 91 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new)) 92 93 static inline long atomic64_add_unless(atomic64_t *v, long a, long u) 94 { 95 long c, old; 96 c = atomic64_read(v); 97 for (;;) { 98 if (unlikely(c == (u))) 99 break; 100 old = atomic64_cmpxchg((v), c, c + (a)); 101 if (likely(old == c)) 102 break; 103 c = old; 104 } 105 return c != (u); 106 } 107 108 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0) 109 110 extern long atomic64_dec_if_positive(atomic64_t *v); 111 112 #endif /* !(__ARCH_SPARC64_ATOMIC__) */ 113