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}}
36 #define DEFAULT_URWLOCK {0,0,0,0,{0,0,0,0}}
38 int _umtx_op_err(void *, int op, u_long, void *, void *) __hidden;
39 int __thr_umutex_lock(struct umutex *mtx, uint32_t id) __hidden;
40 int __thr_umutex_lock_spin(struct umutex *mtx, uint32_t id) __hidden;
41 int __thr_umutex_timedlock(struct umutex *mtx, uint32_t id,
42 const struct timespec *timeout) __hidden;
43 int __thr_umutex_unlock(struct umutex *mtx, uint32_t id) __hidden;
44 int __thr_umutex_trylock(struct umutex *mtx) __hidden;
45 int __thr_umutex_set_ceiling(struct umutex *mtx, uint32_t ceiling,
46 uint32_t *oldceiling) __hidden;
48 void _thr_umutex_init(struct umutex *mtx) __hidden;
49 void _thr_urwlock_init(struct urwlock *rwl) __hidden;
51 int _thr_umtx_wait(volatile long *mtx, long exp,
52 const struct timespec *timeout) __hidden;
53 int _thr_umtx_wait_uint(volatile u_int *mtx, u_int exp,
54 const struct timespec *timeout, int shared) __hidden;
55 int _thr_umtx_timedwait_uint(volatile u_int *mtx, u_int exp, int clockid,
56 const struct timespec *timeout, int shared) __hidden;
57 int _thr_umtx_wake(volatile void *mtx, int count, int shared) __hidden;
58 int _thr_ucond_wait(struct ucond *cv, struct umutex *m,
59 const struct timespec *timeout, int check_unpaking) __hidden;
60 void _thr_ucond_init(struct ucond *cv) __hidden;
61 int _thr_ucond_signal(struct ucond *cv) __hidden;
62 int _thr_ucond_broadcast(struct ucond *cv) __hidden;
64 int __thr_rwlock_rdlock(struct urwlock *rwlock, int flags, struct timespec *tsp) __hidden;
65 int __thr_rwlock_wrlock(struct urwlock *rwlock, struct timespec *tsp) __hidden;
66 int __thr_rwlock_unlock(struct urwlock *rwlock) __hidden;
68 /* Internal used only */
69 void _thr_rwl_rdlock(struct urwlock *rwlock) __hidden;
70 void _thr_rwl_wrlock(struct urwlock *rwlock) __hidden;
71 void _thr_rwl_unlock(struct urwlock *rwlock) __hidden;
74 _thr_umutex_trylock(struct umutex *mtx, uint32_t id)
76 if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_UNOWNED, id))
78 if ((mtx->m_flags & UMUTEX_PRIO_PROTECT) == 0)
80 return (__thr_umutex_trylock(mtx));
84 _thr_umutex_trylock2(struct umutex *mtx, uint32_t id)
86 if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_UNOWNED, id) != 0)
88 if ((uint32_t)mtx->m_owner == UMUTEX_CONTESTED &&
89 __predict_true((mtx->m_flags & (UMUTEX_PRIO_PROTECT | UMUTEX_PRIO_INHERIT)) == 0))
90 if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_CONTESTED, id | UMUTEX_CONTESTED))
96 _thr_umutex_lock(struct umutex *mtx, uint32_t id)
98 if (_thr_umutex_trylock2(mtx, id) == 0)
100 return (__thr_umutex_lock(mtx, id));
104 _thr_umutex_lock_spin(struct umutex *mtx, uint32_t id)
106 if (_thr_umutex_trylock2(mtx, id) == 0)
108 return (__thr_umutex_lock_spin(mtx, id));
112 _thr_umutex_timedlock(struct umutex *mtx, uint32_t id,
113 const struct timespec *timeout)
115 if (_thr_umutex_trylock2(mtx, id) == 0)
117 return (__thr_umutex_timedlock(mtx, id, timeout));
121 _thr_umutex_unlock(struct umutex *mtx, uint32_t id)
123 if (atomic_cmpset_rel_32(&mtx->m_owner, id, UMUTEX_UNOWNED))
125 return (__thr_umutex_unlock(mtx, id));
129 _thr_rwlock_tryrdlock(struct urwlock *rwlock, int flags)
134 if (flags & URWLOCK_PREFER_READER || rwlock->rw_flags & URWLOCK_PREFER_READER)
135 wrflags = URWLOCK_WRITE_OWNER;
137 wrflags = URWLOCK_WRITE_OWNER | URWLOCK_WRITE_WAITERS;
138 state = rwlock->rw_state;
139 while (!(state & wrflags)) {
140 if (__predict_false(URWLOCK_READER_COUNT(state) == URWLOCK_MAX_READERS))
142 if (atomic_cmpset_acq_32(&rwlock->rw_state, state, state + 1))
144 state = rwlock->rw_state;
151 _thr_rwlock_trywrlock(struct urwlock *rwlock)
155 state = rwlock->rw_state;
156 while (!(state & URWLOCK_WRITE_OWNER) && URWLOCK_READER_COUNT(state) == 0) {
157 if (atomic_cmpset_acq_32(&rwlock->rw_state, state, state | URWLOCK_WRITE_OWNER))
159 state = rwlock->rw_state;
166 _thr_rwlock_rdlock(struct urwlock *rwlock, int flags, struct timespec *tsp)
168 if (_thr_rwlock_tryrdlock(rwlock, flags) == 0)
170 return (__thr_rwlock_rdlock(rwlock, flags, tsp));
174 _thr_rwlock_wrlock(struct urwlock *rwlock, struct timespec *tsp)
176 if (_thr_rwlock_trywrlock(rwlock) == 0)
178 return (__thr_rwlock_wrlock(rwlock, tsp));
182 _thr_rwlock_unlock(struct urwlock *rwlock)
186 state = rwlock->rw_state;
187 if (state & URWLOCK_WRITE_OWNER) {
188 if (atomic_cmpset_rel_32(&rwlock->rw_state, URWLOCK_WRITE_OWNER, 0))
192 if (__predict_false(URWLOCK_READER_COUNT(state) == 0))
194 if (!((state & (URWLOCK_WRITE_WAITERS |
195 URWLOCK_READ_WAITERS)) &&
196 URWLOCK_READER_COUNT(state) == 1)) {
197 if (atomic_cmpset_rel_32(&rwlock->rw_state,
200 state = rwlock->rw_state;
206 return (__thr_rwlock_unlock(rwlock));