umtx.h revision 179970
1/*- 2 * Copyright (c) 2002, Jeffrey Roberson <jeff@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * $FreeBSD: head/sys/sys/umtx.h 179970 2008-06-24 07:32:12Z davidxu $ 27 * 28 */ 29 30#ifndef _SYS_UMTX_H_ 31#define _SYS_UMTX_H_ 32 33#include <sys/_types.h> 34#include <sys/limits.h> 35 36/* 37 * See pthread_* 38 */ 39 40#define UMTX_UNOWNED 0x0 41#define UMTX_CONTESTED LONG_MIN 42 43struct umtx { 44 volatile u_long u_owner; /* Owner of the mutex. */ 45}; 46 47#define USYNC_PROCESS_SHARED 0x0001 /* Process shared sync objs */ 48 49#define UMUTEX_UNOWNED 0x0 50#define UMUTEX_CONTESTED 0x80000000U 51 52#define UMUTEX_ERROR_CHECK 0x0002 /* Error-checking mutex */ 53#define UMUTEX_PRIO_INHERIT 0x0004 /* Priority inherited mutex */ 54#define UMUTEX_PRIO_PROTECT 0x0008 /* Priority protect mutex */ 55 56struct umutex { 57 volatile __lwpid_t m_owner; /* Owner of the mutex */ 58 uint32_t m_flags; /* Flags of the mutex */ 59 uint32_t m_ceilings[2]; /* Priority protect ceiling */ 60 uint32_t m_spare[4]; 61}; 62 63struct ucond { 64 volatile uint32_t c_has_waiters; /* Has waiters in kernel */ 65 uint32_t c_flags; /* Flags of the condition variable */ 66 uint32_t c_spare[2]; /* Spare space */ 67}; 68 69struct urwlock { 70 volatile int32_t rw_state; 71 uint32_t rw_flags; 72 uint32_t rw_blocked_readers; 73 uint32_t rw_blocked_writers; 74 uint32_t rw_spare[4]; 75}; 76 77/* urwlock flags */ 78#define URWLOCK_PREFER_READER 0x0002 79 80#define URWLOCK_WRITE_OWNER 0x80000000U 81#define URWLOCK_WRITE_WAITERS 0x40000000U 82#define URWLOCK_READ_WAITERS 0x20000000U 83#define URWLOCK_MAX_READERS 0x1fffffffU 84#define URWLOCK_READER_COUNT(c) ((c) & URWLOCK_MAX_READERS) 85 86/* op code for _umtx_op */ 87#define UMTX_OP_LOCK 0 88#define UMTX_OP_UNLOCK 1 89#define UMTX_OP_WAIT 2 90#define UMTX_OP_WAKE 3 91#define UMTX_OP_MUTEX_TRYLOCK 4 92#define UMTX_OP_MUTEX_LOCK 5 93#define UMTX_OP_MUTEX_UNLOCK 6 94#define UMTX_OP_SET_CEILING 7 95#define UMTX_OP_CV_WAIT 8 96#define UMTX_OP_CV_SIGNAL 9 97#define UMTX_OP_CV_BROADCAST 10 98#define UMTX_OP_WAIT_UINT 11 99#define UMTX_OP_RW_RDLOCK 12 100#define UMTX_OP_RW_WRLOCK 13 101#define UMTX_OP_RW_UNLOCK 14 102#define UMTX_OP_WAIT_UINT_PRIVATE 15 103#define UMTX_OP_WAKE_PRIVATE 16 104#define UMTX_OP_MUTEX_WAIT 17 105#define UMTX_OP_MUTEX_WAKE 18 106#define UMTX_OP_MAX 19 107 108/* flags for UMTX_OP_CV_WAIT */ 109#define UMTX_CHECK_UNPARKING 0x01 110 111#ifndef _KERNEL 112 113int _umtx_op(void *obj, int op, u_long val, void *uaddr, void *uaddr2); 114 115/* 116 * Old (deprecated) userland mutex system calls. 117 */ 118int _umtx_lock(struct umtx *mtx); 119int _umtx_unlock(struct umtx *mtx); 120 121/* 122 * Standard api. Try uncontested acquire/release and asks the 123 * kernel to resolve failures. 124 */ 125static __inline void 126umtx_init(struct umtx *umtx) 127{ 128 umtx->u_owner = UMTX_UNOWNED; 129} 130 131static __inline u_long 132umtx_owner(struct umtx *umtx) 133{ 134 return (umtx->u_owner & ~LONG_MIN); 135} 136 137static __inline int 138umtx_lock(struct umtx *umtx, u_long id) 139{ 140 if (atomic_cmpset_acq_long(&umtx->u_owner, UMTX_UNOWNED, id) == 0) 141 if (_umtx_lock(umtx) == -1) 142 return (errno); 143 return (0); 144} 145 146static __inline int 147umtx_trylock(struct umtx *umtx, u_long id) 148{ 149 if (atomic_cmpset_acq_long(&umtx->u_owner, UMTX_UNOWNED, id) == 0) 150 return (EBUSY); 151 return (0); 152} 153 154static __inline int 155umtx_timedlock(struct umtx *umtx, u_long id, const struct timespec *timeout) 156{ 157 if (atomic_cmpset_acq_long(&umtx->u_owner, UMTX_UNOWNED, id) == 0) 158 if (_umtx_op(umtx, UMTX_OP_LOCK, id, 0, 159 __DECONST(void *, timeout)) == -1) 160 return (errno); 161 return (0); 162} 163 164static __inline int 165umtx_unlock(struct umtx *umtx, u_long id) 166{ 167 if (atomic_cmpset_rel_long(&umtx->u_owner, id, UMTX_UNOWNED) == 0) 168 if (_umtx_unlock(umtx) == -1) 169 return (errno); 170 return (0); 171} 172 173static __inline int 174umtx_wait(u_long *p, long val, const struct timespec *timeout) 175{ 176 if (_umtx_op(p, UMTX_OP_WAIT, val, 0, 177 __DECONST(void *, timeout)) == -1) 178 return (errno); 179 return (0); 180} 181 182/* Wake threads waiting on a user address. */ 183static __inline int 184umtx_wake(u_long *p, int nr_wakeup) 185{ 186 if (_umtx_op(p, UMTX_OP_WAKE, nr_wakeup, 0, 0) == -1) 187 return (errno); 188 return (0); 189} 190 191#else 192 193struct thread; 194 195struct umtx_q *umtxq_alloc(void); 196void umtxq_free(struct umtx_q *); 197int kern_umtx_wake(struct thread *, void *, int, int); 198void umtx_pi_adjust(struct thread *, u_char); 199void umtx_thread_init(struct thread *); 200void umtx_thread_fini(struct thread *); 201void umtx_thread_alloc(struct thread *); 202void umtx_thread_exit(struct thread *); 203#endif /* !_KERNEL */ 204#endif /* !_SYS_UMTX_H_ */ 205