1 /*- 2 * Copyright (c) 2010 Isilon Systems, Inc. 3 * Copyright (c) 2010 iX Systems, Inc. 4 * Copyright (c) 2010 Panasas, Inc. 5 * Copyright (c) 2013-2017 Mellanox Technologies, Ltd. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice unmodified, this list of conditions, and the following 13 * disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 #ifndef _ATOMIC_LONG_H_ 32 #define _ATOMIC_LONG_H_ 33 34 #include <linux/compiler.h> 35 #include <sys/types.h> 36 #include <machine/atomic.h> 37 38 #define ATOMIC_LONG_INIT(x) { .counter = (x) } 39 40 typedef struct { 41 volatile long counter; 42 } atomic_long_t; 43 44 #define atomic_long_add(i, v) atomic_long_add_return((i), (v)) 45 #define atomic_long_sub(i, v) atomic_long_add_return(-(i), (v)) 46 #define atomic_long_inc_return(v) atomic_long_add_return(1, (v)) 47 #define atomic_long_inc_not_zero(v) atomic_long_add_unless((v), 1, 0) 48 49 static inline long 50 atomic_long_add_return(long i, atomic_long_t *v) 51 { 52 return i + atomic_fetchadd_long(&v->counter, i); 53 } 54 55 static inline void 56 atomic_long_set(atomic_long_t *v, long i) 57 { 58 WRITE_ONCE(v->counter, i); 59 } 60 61 static inline long 62 atomic_long_read(atomic_long_t *v) 63 { 64 return READ_ONCE(v->counter); 65 } 66 67 static inline long 68 atomic_long_inc(atomic_long_t *v) 69 { 70 return atomic_fetchadd_long(&v->counter, 1) + 1; 71 } 72 73 static inline long 74 atomic_long_dec(atomic_long_t *v) 75 { 76 return atomic_fetchadd_long(&v->counter, -1) - 1; 77 } 78 79 static inline long 80 atomic_long_xchg(atomic_long_t *v, long val) 81 { 82 return atomic_swap_long(&v->counter, val); 83 } 84 85 static inline long 86 atomic_long_cmpxchg(atomic_long_t *v, long old, long new) 87 { 88 long ret = old; 89 90 for (;;) { 91 if (atomic_fcmpset_long(&v->counter, &ret, new)) 92 break; 93 if (ret != old) 94 break; 95 } 96 return (ret); 97 } 98 99 static inline int 100 atomic_long_add_unless(atomic_long_t *v, long a, long u) 101 { 102 long c = atomic_long_read(v); 103 104 for (;;) { 105 if (unlikely(c == u)) 106 break; 107 if (likely(atomic_fcmpset_long(&v->counter, &c, c + a))) 108 break; 109 } 110 return (c != u); 111 } 112 113 static inline long 114 atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u) 115 { 116 long c = atomic_long_read(v); 117 118 for (;;) { 119 if (unlikely(c == u)) 120 break; 121 if (likely(atomic_fcmpset_long(&v->counter, &c, c + a))) 122 break; 123 } 124 return (c); 125 } 126 127 static inline long 128 atomic_long_dec_and_test(atomic_long_t *v) 129 { 130 long i = atomic_long_add(-1, v); 131 return i == 0 ; 132 } 133 134 #endif /* _ATOMIC_LONG_H_ */ 135