1 /* $OpenBSD: mutex.h,v 1.4 2010/01/10 04:07:18 kettenis Exp $ */ 2 3 /* 4 * Copyright (c) 2004 Artur Grabowski <art@openbsd.org> 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 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 17 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 18 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 19 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #ifndef _MACHINE_MUTEX_H_ 29 #define _MACHINE_MUTEX_H_ 30 31 #define MUTEX_LOCKED { 0, 0, 0, 0 } 32 #define MUTEX_UNLOCKED { 1, 1, 1, 1 } 33 34 /* Note: mtx_lock must be 16-byte aligned. */ 35 struct mutex { 36 volatile int mtx_lock[4]; 37 int mtx_wantipl; 38 int mtx_oldipl; 39 void *mtx_owner; 40 }; 41 42 void mtx_init(struct mutex *, int); 43 44 #define MUTEX_INITIALIZER(ipl) { MUTEX_UNLOCKED, (ipl), 0, NULL } 45 46 #ifdef DIAGNOSTIC 47 #define MUTEX_ASSERT_LOCKED(mtx) do { \ 48 if ((mtx)->mtx_lock[0] == 1 && (mtx)->mtx_lock[1] == 1 && \ 49 (mtx)->mtx_lock[2] == 1 && (mtx)->mtx_lock[3] == 1) \ 50 panic("mutex %p not held in %s", (mtx), __func__); \ 51 } while (0) 52 53 #define MUTEX_ASSERT_UNLOCKED(mtx) do { \ 54 if ((mtx)->mtx_lock[0] != 1 && (mtx)->mtx_lock[1] != 1 && \ 55 (mtx)->mtx_lock[2] != 1 && (mtx)->mtx_lock[3] != 1) \ 56 panic("mutex %p held in %s", (mtx), __func__); \ 57 } while (0) 58 #else 59 #define MUTEX_ASSERT_LOCKED(mtx) do { } while (0) 60 #define MUTEX_ASSERT_UNLOCKED(mtx) do { } while (0) 61 #endif 62 63 #define MUTEX_OLDIPL(mtx) (mtx)->mtx_oldipl 64 65 #endif 66