2 * Copyright (c) 2005 David Xu <davidxu@freebsd.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 #ifndef _THR_FBSD_UMTX_H_
30 #define _THR_FBSD_UMTX_H_
35 #define DEFAULT_UMUTEX {0,0, {0,0},{0,0,0,0}}
37 int _umtx_op_err(void *, int op, u_long, void *, void *) __hidden;
38 int __thr_umutex_lock(struct umutex *mtx, uint32_t id) __hidden;
39 int __thr_umutex_timedlock(struct umutex *mtx, uint32_t id,
40 const struct timespec *timeout) __hidden;
41 int __thr_umutex_unlock(struct umutex *mtx, uint32_t id) __hidden;
42 int __thr_umutex_trylock(struct umutex *mtx) __hidden;
43 int __thr_umutex_set_ceiling(struct umutex *mtx, uint32_t ceiling,
44 uint32_t *oldceiling) __hidden;
46 void _thr_umutex_init(struct umutex *mtx) __hidden;
47 int _thr_umtx_wait(volatile long *mtx, long exp,
48 const struct timespec *timeout) __hidden;
49 int _thr_umtx_wait_uint(volatile u_int *mtx, u_int exp,
50 const struct timespec *timeout, int shared) __hidden;
51 int _thr_umtx_wake(volatile void *mtx, int count, int shared) __hidden;
52 int _thr_ucond_wait(struct ucond *cv, struct umutex *m,
53 const struct timespec *timeout, int check_unpaking) __hidden;
54 void _thr_ucond_init(struct ucond *cv) __hidden;
55 int _thr_ucond_signal(struct ucond *cv) __hidden;
56 int _thr_ucond_broadcast(struct ucond *cv) __hidden;
58 int __thr_rwlock_rdlock(struct urwlock *rwlock, int flags, struct timespec *tsp) __hidden;
59 int __thr_rwlock_wrlock(struct urwlock *rwlock, struct timespec *tsp) __hidden;
60 int __thr_rwlock_unlock(struct urwlock *rwlock) __hidden;
63 _thr_umutex_trylock(struct umutex *mtx, uint32_t id)
65 if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_UNOWNED, id))
67 if ((mtx->m_flags & UMUTEX_PRIO_PROTECT) == 0)
69 return (__thr_umutex_trylock(mtx));
73 _thr_umutex_trylock2(struct umutex *mtx, uint32_t id)
75 if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_UNOWNED, id) != 0)
77 if ((uint32_t)mtx->m_owner == UMUTEX_CONTESTED &&
78 __predict_true((mtx->m_flags & (UMUTEX_PRIO_PROTECT | UMUTEX_PRIO_INHERIT)) == 0))
79 if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_CONTESTED, id | UMUTEX_CONTESTED))
85 _thr_umutex_lock(struct umutex *mtx, uint32_t id)
87 if (_thr_umutex_trylock2(mtx, id) == 0)
89 return (__thr_umutex_lock(mtx, id));
93 _thr_umutex_timedlock(struct umutex *mtx, uint32_t id,
94 const struct timespec *timeout)
96 if (_thr_umutex_trylock2(mtx, id) == 0)
98 return (__thr_umutex_timedlock(mtx, id, timeout));
102 _thr_umutex_unlock(struct umutex *mtx, uint32_t id)
104 if (atomic_cmpset_rel_32(&mtx->m_owner, id, UMUTEX_UNOWNED))
106 return (__thr_umutex_unlock(mtx, id));
110 _thr_rwlock_tryrdlock(struct urwlock *rwlock, int flags)
115 if (flags & URWLOCK_PREFER_READER || rwlock->rw_flags & URWLOCK_PREFER_READER)
116 wrflags = URWLOCK_WRITE_OWNER;
118 wrflags = URWLOCK_WRITE_OWNER | URWLOCK_WRITE_WAITERS;
119 state = rwlock->rw_state;
120 while (!(state & wrflags)) {
121 if (__predict_false(URWLOCK_READER_COUNT(state) == URWLOCK_MAX_READERS))
123 if (atomic_cmpset_acq_32(&rwlock->rw_state, state, state + 1))
125 state = rwlock->rw_state;
132 _thr_rwlock_trywrlock(struct urwlock *rwlock)
136 state = rwlock->rw_state;
137 while (!(state & URWLOCK_WRITE_OWNER) && URWLOCK_READER_COUNT(state) == 0) {
138 if (atomic_cmpset_acq_32(&rwlock->rw_state, state, state | URWLOCK_WRITE_OWNER))
140 state = rwlock->rw_state;
147 _thr_rwlock_rdlock(struct urwlock *rwlock, int flags, struct timespec *tsp)
149 if (_thr_rwlock_tryrdlock(rwlock, flags) == 0)
151 return (__thr_rwlock_rdlock(rwlock, flags, tsp));
155 _thr_rwlock_wrlock(struct urwlock *rwlock, struct timespec *tsp)
157 if (_thr_rwlock_trywrlock(rwlock) == 0)
159 return (__thr_rwlock_wrlock(rwlock, tsp));
163 _thr_rwlock_unlock(struct urwlock *rwlock)
167 state = rwlock->rw_state;
168 if (state & URWLOCK_WRITE_OWNER) {
169 if (atomic_cmpset_rel_32(&rwlock->rw_state, URWLOCK_WRITE_OWNER, 0))
173 if (__predict_false(URWLOCK_READER_COUNT(state) == 0))
175 if (!((state & (URWLOCK_WRITE_WAITERS |
176 URWLOCK_READ_WAITERS)) &&
177 URWLOCK_READER_COUNT(state) == 1)) {
178 if (atomic_cmpset_rel_32(&rwlock->rw_state,
181 state = rwlock->rw_state;
187 return (__thr_rwlock_unlock(rwlock));