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 __thr_umutex_lock(struct umutex *mtx, uint32_t id) __hidden;
38 int __thr_umutex_timedlock(struct umutex *mtx, uint32_t id,
39 const struct timespec *timeout) __hidden;
40 int __thr_umutex_unlock(struct umutex *mtx, uint32_t id) __hidden;
41 int __thr_umutex_trylock(struct umutex *mtx) __hidden;
42 int __thr_umutex_set_ceiling(struct umutex *mtx, uint32_t ceiling,
43 uint32_t *oldceiling) __hidden;
45 void _thr_umutex_init(struct umutex *mtx) __hidden;
46 int _thr_umtx_wait(volatile long *mtx, long exp,
47 const struct timespec *timeout) __hidden;
48 int _thr_umtx_wait_uint(volatile u_int *mtx, u_int exp,
49 const struct timespec *timeout, int shared) __hidden;
50 int _thr_umtx_wake(volatile void *mtx, int count, int shared) __hidden;
51 int _thr_ucond_wait(struct ucond *cv, struct umutex *m,
52 const struct timespec *timeout, int check_unpaking) __hidden;
53 void _thr_ucond_init(struct ucond *cv) __hidden;
54 int _thr_ucond_signal(struct ucond *cv) __hidden;
55 int _thr_ucond_broadcast(struct ucond *cv) __hidden;
57 int __thr_rwlock_rdlock(struct urwlock *rwlock, int flags, struct timespec *tsp) __hidden;
58 int __thr_rwlock_wrlock(struct urwlock *rwlock, struct timespec *tsp) __hidden;
59 int __thr_rwlock_unlock(struct urwlock *rwlock) __hidden;
62 _thr_umutex_trylock(struct umutex *mtx, uint32_t id)
64 if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_UNOWNED, id))
66 if ((mtx->m_flags & UMUTEX_PRIO_PROTECT) == 0)
68 return (__thr_umutex_trylock(mtx));
72 _thr_umutex_trylock2(struct umutex *mtx, uint32_t id)
74 if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_UNOWNED, id) != 0)
76 if ((uint32_t)mtx->m_owner == UMUTEX_CONTESTED &&
77 __predict_true((mtx->m_flags & (UMUTEX_PRIO_PROTECT | UMUTEX_PRIO_INHERIT)) == 0))
78 if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_CONTESTED, id | UMUTEX_CONTESTED))
84 _thr_umutex_lock(struct umutex *mtx, uint32_t id)
86 if (_thr_umutex_trylock2(mtx, id) == 0)
88 return (__thr_umutex_lock(mtx, id));
92 _thr_umutex_timedlock(struct umutex *mtx, uint32_t id,
93 const struct timespec *timeout)
95 if (_thr_umutex_trylock2(mtx, id) == 0)
97 return (__thr_umutex_timedlock(mtx, id, timeout));
101 _thr_umutex_unlock(struct umutex *mtx, uint32_t id)
103 if (atomic_cmpset_rel_32(&mtx->m_owner, id, UMUTEX_UNOWNED))
105 return (__thr_umutex_unlock(mtx, id));
109 _thr_rwlock_tryrdlock(struct urwlock *rwlock, int flags)
114 if (flags & URWLOCK_PREFER_READER || rwlock->rw_flags & URWLOCK_PREFER_READER)
115 wrflags = URWLOCK_WRITE_OWNER;
117 wrflags = URWLOCK_WRITE_OWNER | URWLOCK_WRITE_WAITERS;
118 state = rwlock->rw_state;
119 while (!(state & wrflags)) {
120 if (__predict_false(URWLOCK_READER_COUNT(state) == URWLOCK_MAX_READERS))
122 if (atomic_cmpset_acq_32(&rwlock->rw_state, state, state + 1))
124 state = rwlock->rw_state;
131 _thr_rwlock_trywrlock(struct urwlock *rwlock)
135 state = rwlock->rw_state;
136 while (!(state & URWLOCK_WRITE_OWNER) && URWLOCK_READER_COUNT(state) == 0) {
137 if (atomic_cmpset_acq_32(&rwlock->rw_state, state, state | URWLOCK_WRITE_OWNER))
139 state = rwlock->rw_state;
146 _thr_rwlock_rdlock(struct urwlock *rwlock, int flags, struct timespec *tsp)
148 if (_thr_rwlock_tryrdlock(rwlock, flags) == 0)
150 return (__thr_rwlock_rdlock(rwlock, flags, tsp));
154 _thr_rwlock_wrlock(struct urwlock *rwlock, struct timespec *tsp)
156 if (_thr_rwlock_trywrlock(rwlock) == 0)
158 return (__thr_rwlock_wrlock(rwlock, tsp));
162 _thr_rwlock_unlock(struct urwlock *rwlock)
166 state = rwlock->rw_state;
167 if (state & URWLOCK_WRITE_OWNER) {
168 if (atomic_cmpset_rel_32(&rwlock->rw_state, URWLOCK_WRITE_OWNER, 0))
172 if (__predict_false(URWLOCK_READER_COUNT(state) == 0))
174 if (!((state & URWLOCK_WRITE_WAITERS) && URWLOCK_READER_COUNT(state) == 1)) {
175 if (atomic_cmpset_rel_32(&rwlock->rw_state, state, state-1))
177 state = rwlock->rw_state;
183 return (__thr_rwlock_unlock(rwlock));