1 /* $NetBSD: lock.h,v 1.5 2000/07/01 06:41:06 matt Exp $ */ 2 3 /* 4 * Copyright (c) 2000 Ludd, University of Lule}, Sweden. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed at Ludd, University of Lule}. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #ifndef _VAX_LOCK_H_ 34 #define _VAX_LOCK_H_ 35 36 typedef __volatile int __cpu_simple_lock_t; 37 38 #define __SIMPLELOCK_LOCKED 1 39 #define __SIMPLELOCK_UNLOCKED 0 40 41 static __inline void 42 __cpu_simple_lock_init(__cpu_simple_lock_t *alp) 43 { 44 *alp = __SIMPLELOCK_UNLOCKED; 45 } 46 47 static __inline void 48 __cpu_simple_lock(__cpu_simple_lock_t *alp) 49 { 50 __asm__ __volatile ("1:;bbssi $0, %0, 1b" 51 : /* No output */ 52 : "m"(*alp)); 53 } 54 55 static __inline void 56 __cpu_simple_unlock(__cpu_simple_lock_t *alp) 57 { 58 *alp = __SIMPLELOCK_UNLOCKED; 59 } 60 61 static __inline int 62 __cpu_simple_lock_try(__cpu_simple_lock_t *alp) 63 { 64 int ret; 65 66 __asm__ __volatile ("movl $0,%0;bbssi $0,%1,1f;incl %0;1:" 67 : "=&r"(ret) 68 : "m"(*alp)); 69 70 return ret; 71 } 72 73 #endif /* _VAX_LOCK_H_ */ 74