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, 2014 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 <sys/cdefs.h> 35 #include <sys/types.h> 36 #include <machine/atomic.h> 37 38 typedef struct { 39 volatile long counter; 40 } atomic_long_t; 41 42 #define atomic_long_add(i, v) atomic_long_add_return((i), (v)) 43 #define atomic_long_inc_return(v) atomic_long_add_return(1, (v)) 44 #define atomic_long_inc_not_zero(v) atomic_long_add_unless((v), 1, 0) 45 46 static inline long 47 atomic_long_add_return(long i, atomic_long_t *v) 48 { 49 return i + atomic_fetchadd_long(&v->counter, i); 50 } 51 52 static inline void 53 atomic_long_set(atomic_long_t *v, long i) 54 { 55 atomic_store_rel_long(&v->counter, i); 56 } 57 58 static inline long 59 atomic_long_read(atomic_long_t *v) 60 { 61 return atomic_load_acq_long(&v->counter); 62 } 63 64 static inline long 65 atomic_long_inc(atomic_long_t *v) 66 { 67 return atomic_fetchadd_long(&v->counter, 1) + 1; 68 } 69 70 static inline long 71 atomic_long_dec(atomic_long_t *v) 72 { 73 return atomic_fetchadd_long(&v->counter, -1) - 1; 74 } 75 76 static inline int 77 atomic_long_add_unless(atomic_long_t *v, long a, long u) 78 { 79 long c; 80 81 for (;;) { 82 c = atomic_long_read(v); 83 if (unlikely(c == u)) 84 break; 85 if (likely(atomic_cmpset_long(&v->counter, c, c + a))) 86 break; 87 } 88 return (c != u); 89 } 90 91 static inline long 92 atomic_long_dec_and_test(atomic_long_t *v) 93 { 94 long i = atomic_long_add(-1, v); 95 return i == 0 ; 96 } 97 98 #endif /* _ATOMIC_LONG_H_ */ 99