/* $NetBSD: mutex.h,v 1.17.4.1 2023/08/09 17:42:02 martin Exp $ */ /*- * Copyright (c) 2002, 2007 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Jason R. Thorpe and Andrew Doran. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #ifndef _VAX_MUTEX_H_ #define _VAX_MUTEX_H_ /* * The VAX mutex implementation is troublesome, because VAX lacks a * compare-and-swap operation. * * So we emulate compare-and-swap by raising IPL to lock out interrupts * and (if MP) using BBSSI/BBCCI to lock out the other processors. */ #include #ifndef __MUTEX_PRIVATE struct kmutex { uintptr_t mtx_pad1; }; #else /* __MUTEX_PRIVATE */ #include struct kmutex { union { /* Adaptive mutex */ volatile uintptr_t mtxa_owner; /* 0-3 */ /* Spin mutex */ struct { volatile uint8_t mtxs_dummy; ipl_cookie_t mtxs_ipl; __cpu_simple_lock_t mtxs_lock; volatile uint8_t mtxs_unused; } s; } u; }; #define mtx_owner u.mtxa_owner #define mtx_ipl u.s.mtxs_ipl #define mtx_lock u.s.mtxs_lock #define __HAVE_MUTEX_STUBS 1 #define __HAVE_SPIN_MUTEX_STUBS 1 #define __HAVE_SIMPLE_MUTEXES 1 #endif /* __MUTEX_PRIVATE */ #endif /* _VAX_MUTEX_H_ */