1 /* $NetBSD: mutex.h,v 1.3 2008/04/28 20:23:25 martin Exp $ */ 2 3 /*- 4 * Copyright (c) 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Takayoshi Kochi. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #ifndef _IA64_MUTEX_H_ 33 #define _IA64_MUTEX_H_ 34 35 struct kmutex { 36 union { 37 volatile uintptr_t mtxa_owner; 38 #ifdef __MUTEX_PRIVATE 39 struct { 40 volatile uint8_t mtxs_dummy; 41 ipl_cookie_t mtxs_ipl; 42 __cpu_simple_lock_t mtxs_lock; 43 volatile uint8_t mtxs_unused; 44 } s; 45 #endif 46 } u; 47 }; 48 49 #ifdef __MUTEX_PRIVATE 50 51 /* uintptr_t */ 52 #define mtx_owner u.mtxa_owner 53 /* ipl_cookie_t */ 54 #define mtx_ipl u.s.mtxs_ipl 55 /* __cpu_simple_lock_t */ 56 #define mtx_lock u.s.mtxs_lock 57 58 /* XXX when we implement mutex_enter()/mutex_exit(), uncomment this 59 #define __HAVE_MUTEX_STUBS 1 60 */ 61 /* XXX when we implement mutex_spin_enter()/mutex_spin_exit(), uncomment this 62 #define __HAVE_SPIN_MUTEX_STUBS 1 63 */ 64 #define __HAVE_SIMPLE_MUTEXES 1 65 66 /* 67 * MUTEX_RECEIVE: no memory barrier required, atomic_cas implies a load fence. 68 */ 69 #define MUTEX_RECEIVE(mtx) /* nothing */ 70 71 /* 72 * MUTEX_GIVE: no memory barrier required, as _lock_cas() will take care of it. 73 */ 74 #define MUTEX_GIVE(mtx) /* nothing */ 75 76 #define MUTEX_CAS(ptr, old, new) \ 77 (atomic_cas_ulong((volatile unsigned long *)(ptr), (old), (new)) == (old)) 78 79 #endif /* __MUTEX_PRIVATE */ 80 81 #endif /* _IA64_MUTEX_H_ */ 82