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/cdefs.h> 28 #include <sys/param.h> 29 #include <sys/lock.h> 30 #include <sys/mutex.h> 31 #include <sys/atomic.h> 32 33 #if !defined(__LP64__) && !defined(__mips_n32) && \ 34 !defined(ARM_HAVE_ATOMIC64) && !defined(I386_HAVE_ATOMIC64) && \ 35 !defined(HAS_EMULATED_ATOMIC64) 36 37 #ifdef _KERNEL 38 #include <sys/kernel.h> 39 40 struct mtx atomic_mtx; 41 MTX_SYSINIT(atomic, &atomic_mtx, "atomic", MTX_DEF); 42 #else 43 #include <pthread.h> 44 45 #define mtx_lock(lock) pthread_mutex_lock(lock) 46 #define mtx_unlock(lock) pthread_mutex_unlock(lock) 47 48 static pthread_mutex_t atomic_mtx; 49 50 static __attribute__((constructor)) void 51 atomic_init(void) 52 { 53 pthread_mutex_init(&atomic_mtx, NULL); 54 } 55 #endif 56 57 void 58 atomic_add_64(volatile uint64_t *target, int64_t delta) 59 { 60 61 mtx_lock(&atomic_mtx); 62 *target += delta; 63 mtx_unlock(&atomic_mtx); 64 } 65 66 void 67 atomic_dec_64(volatile uint64_t *target) 68 { 69 70 mtx_lock(&atomic_mtx); 71 *target -= 1; 72 mtx_unlock(&atomic_mtx); 73 } 74 75 uint64_t 76 atomic_swap_64(volatile uint64_t *a, uint64_t value) 77 { 78 uint64_t ret; 79 80 mtx_lock(&atomic_mtx); 81 ret = *a; 82 *a = value; 83 mtx_unlock(&atomic_mtx); 84 return (ret); 85 } 86 87 uint64_t 88 atomic_load_64(volatile uint64_t *a) 89 { 90 uint64_t ret; 91 92 mtx_lock(&atomic_mtx); 93 ret = *a; 94 mtx_unlock(&atomic_mtx); 95 return (ret); 96 } 97 98 uint64_t 99 atomic_add_64_nv(volatile uint64_t *target, int64_t delta) 100 { 101 uint64_t newval; 102 103 mtx_lock(&atomic_mtx); 104 newval = (*target += delta); 105 mtx_unlock(&atomic_mtx); 106 return (newval); 107 } 108 109 uint64_t 110 atomic_cas_64(volatile uint64_t *target, uint64_t cmp, uint64_t newval) 111 { 112 uint64_t oldval; 113 114 mtx_lock(&atomic_mtx); 115 oldval = *target; 116 if (oldval == cmp) 117 *target = newval; 118 mtx_unlock(&atomic_mtx); 119 return (oldval); 120 } 121 #endif 122