1 /* 2 * Copyright (c) 2009 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 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. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #ifndef _SYS_MUTEX_H_ 36 #define _SYS_MUTEX_H_ 37 38 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES) 39 40 #ifndef _SYS_TYPES_H_ 41 #include <sys/types.h> 42 #endif 43 #include <machine/atomic.h> 44 #include <machine/cpufunc.h> 45 46 /* 47 * The general mutex structure provides recursive shared and exclusive 48 * locks, downgrade, a non-blocking upgrade, and various other functions. 49 * 50 * The structure is 16-byte aligned and either 16 or 32 bytes, designed 51 * for 32 or 64 bit cpus. 52 */ 53 struct thread; 54 55 struct mtx_link { 56 struct mtx_link *next; 57 struct mtx_link *prev; 58 struct thread *owner; 59 int state; 60 }; 61 62 typedef struct mtx_link *mtx_link_t; 63 64 struct mtx { 65 volatile u_int mtx_lock; 66 int mtx_refs; 67 struct thread *mtx_owner; 68 mtx_link_t mtx_link; 69 } __cachealign; 70 71 typedef struct mtx *mtx_t; 72 73 #define MTX_INITIALIZER { .mtx_lock = 0, .mtx_refs = 0, \ 74 .mtx_owner = NULL, .mtx_link = NULL } 75 76 #define MTX_EXCLUSIVE 0x80000000 77 #define MTX_SHWANTED 0x40000000 78 #define MTX_EXWANTED 0x20000000 79 #define MTX_EXLINK 0x10000000 80 #define MTX_MASK 0x0FFFFFFF 81 82 #define MTX_PCATCH 0x00000001 83 84 #define MTX_OWNER_NONE NULL 85 #define MTX_OWNER_ANON ((struct thread *)-2) 86 87 #define MTX_LINK_IDLE 0 88 #define MTX_LINK_ABORTED -1 89 #define MTX_LINK_LINKED 1 90 #define MTX_LINK_ACQUIRED 2 91 92 #endif 93 94 /* 95 * See also sys/mutex2.h 96 */ 97 #ifdef _KERNEL 98 99 int _mtx_lock_ex_link(mtx_t mtx, mtx_link_t link, const char *ident, int flags, int to); 100 int _mtx_lock_ex(mtx_t mtx, const char *ident, int flags, int to); 101 int _mtx_lock_sh(mtx_t mtx, const char *ident, int flags, int to); 102 int _mtx_lock_ex_quick(mtx_t mtx, const char *ident); 103 int _mtx_lock_sh_quick(mtx_t mtx, const char *ident); 104 void _mtx_spinlock(mtx_t mtx); 105 int _mtx_spinlock_try(mtx_t mtx); 106 int _mtx_lock_ex_try(mtx_t mtx); 107 int _mtx_lock_sh_try(mtx_t mtx); 108 void _mtx_downgrade(mtx_t mtx); 109 int _mtx_upgrade_try(mtx_t mtx); 110 void _mtx_unlock(mtx_t mtx); 111 void mtx_abort_ex_link(mtx_t mtx, mtx_link_t link); 112 113 #endif 114 115 #endif 116