1 /*- 2 * Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/param.h> 28 #include <sys/lock.h> 29 #include <sys/mutex.h> 30 #include <sys/atomic.h> 31 32 #if !defined(__LP64__) && !defined(__mips_n32) && \ 33 !defined(ARM_HAVE_ATOMIC64) && !defined(I386_HAVE_ATOMIC64) && \ 34 !defined(HAS_EMULATED_ATOMIC64) 35 36 #ifdef _KERNEL 37 #include <sys/kernel.h> 38 39 struct mtx atomic_mtx; 40 MTX_SYSINIT(atomic, &atomic_mtx, "atomic", MTX_DEF); 41 #else 42 #include <pthread.h> 43 44 #define mtx_lock(lock) pthread_mutex_lock(lock) 45 #define mtx_unlock(lock) pthread_mutex_unlock(lock) 46 47 static pthread_mutex_t atomic_mtx; 48 49 static __attribute__((constructor)) void 50 atomic_init(void) 51 { 52 pthread_mutex_init(&atomic_mtx, NULL); 53 } 54 #endif 55 56 void 57 atomic_add_64(volatile uint64_t *target, int64_t delta) 58 { 59 60 mtx_lock(&atomic_mtx); 61 *target += delta; 62 mtx_unlock(&atomic_mtx); 63 } 64 65 void 66 atomic_dec_64(volatile uint64_t *target) 67 { 68 69 mtx_lock(&atomic_mtx); 70 *target -= 1; 71 mtx_unlock(&atomic_mtx); 72 } 73 74 uint64_t 75 atomic_swap_64(volatile uint64_t *a, uint64_t value) 76 { 77 uint64_t ret; 78 79 mtx_lock(&atomic_mtx); 80 ret = *a; 81 *a = value; 82 mtx_unlock(&atomic_mtx); 83 return (ret); 84 } 85 86 uint64_t 87 atomic_load_64(volatile uint64_t *a) 88 { 89 uint64_t ret; 90 91 mtx_lock(&atomic_mtx); 92 ret = *a; 93 mtx_unlock(&atomic_mtx); 94 return (ret); 95 } 96 97 uint64_t 98 atomic_add_64_nv(volatile uint64_t *target, int64_t delta) 99 { 100 uint64_t newval; 101 102 mtx_lock(&atomic_mtx); 103 newval = (*target += delta); 104 mtx_unlock(&atomic_mtx); 105 return (newval); 106 } 107 108 uint64_t 109 atomic_cas_64(volatile uint64_t *target, uint64_t cmp, uint64_t newval) 110 { 111 uint64_t oldval; 112 113 mtx_lock(&atomic_mtx); 114 oldval = *target; 115 if (oldval == cmp) 116 *target = newval; 117 mtx_unlock(&atomic_mtx); 118 return (oldval); 119 } 120 #endif 121