thr_umtx.h revision 177850
1144518Sdavidxu/*- 2144518Sdavidxu * Copyright (c) 2005 David Xu <davidxu@freebsd.org> 3144518Sdavidxu * All rights reserved. 4144518Sdavidxu * 5144518Sdavidxu * Redistribution and use in source and binary forms, with or without 6144518Sdavidxu * modification, are permitted provided that the following conditions 7144518Sdavidxu * are met: 8144518Sdavidxu * 1. Redistributions of source code must retain the above copyright 9144518Sdavidxu * notice, this list of conditions and the following disclaimer. 10144518Sdavidxu * 2. Redistributions in binary form must reproduce the above copyright 11144518Sdavidxu * notice, this list of conditions and the following disclaimer in the 12144518Sdavidxu * documentation and/or other materials provided with the distribution. 13144518Sdavidxu * 14144518Sdavidxu * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15144518Sdavidxu * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16144518Sdavidxu * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17144518Sdavidxu * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18144518Sdavidxu * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19144518Sdavidxu * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20144518Sdavidxu * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21144518Sdavidxu * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22144518Sdavidxu * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23144518Sdavidxu * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24144518Sdavidxu * SUCH DAMAGE. 25144518Sdavidxu * 26144518Sdavidxu * $FreeBSD: head/lib/libthr/thread/thr_umtx.h 177850 2008-04-02 04:32:31Z davidxu $ 27144518Sdavidxu */ 28144518Sdavidxu 29144518Sdavidxu#ifndef _THR_FBSD_UMTX_H_ 30144518Sdavidxu#define _THR_FBSD_UMTX_H_ 31144518Sdavidxu 32162061Sdavidxu#include <strings.h> 33144518Sdavidxu#include <sys/umtx.h> 34144518Sdavidxu 35173801Sdavidxu#define DEFAULT_UMUTEX {0,0, {0,0},{0,0,0,0}} 36162061Sdavidxu 37163334Sdavidxuint __thr_umutex_lock(struct umutex *mtx) __hidden; 38163334Sdavidxuint __thr_umutex_timedlock(struct umutex *mtx, 39161680Sdavidxu const struct timespec *timeout) __hidden; 40163334Sdavidxuint __thr_umutex_unlock(struct umutex *mtx) __hidden; 41163334Sdavidxuint __thr_umutex_trylock(struct umutex *mtx) __hidden; 42161680Sdavidxuint __thr_umutex_set_ceiling(struct umutex *mtx, uint32_t ceiling, 43161680Sdavidxu uint32_t *oldceiling) __hidden; 44161680Sdavidxu 45163334Sdavidxuvoid _thr_umutex_init(struct umutex *mtx) __hidden; 46173801Sdavidxuint _thr_umtx_wait(volatile long *mtx, long exp, 47162061Sdavidxu const struct timespec *timeout) __hidden; 48173801Sdavidxuint _thr_umtx_wait_uint(volatile u_int *mtx, u_int exp, 49173801Sdavidxu const struct timespec *timeout) __hidden; 50173801Sdavidxuint _thr_umtx_wake(volatile void *mtx, int count) __hidden; 51164877Sdavidxuint _thr_ucond_wait(struct ucond *cv, struct umutex *m, 52164902Sdavidxu const struct timespec *timeout, int check_unpaking) __hidden; 53164902Sdavidxuvoid _thr_ucond_init(struct ucond *cv) __hidden; 54164902Sdavidxuint _thr_ucond_signal(struct ucond *cv) __hidden; 55164902Sdavidxuint _thr_ucond_broadcast(struct ucond *cv) __hidden; 56162061Sdavidxu 57177850Sdavidxuint __thr_rwlock_rdlock(struct urwlock *rwlock, int flags, struct timespec *tsp) __hidden; 58177850Sdavidxuint __thr_rwlock_wrlock(struct urwlock *rwlock, struct timespec *tsp) __hidden; 59177850Sdavidxuint __thr_rwlock_unlock(struct urwlock *rwlock) __hidden; 60177850Sdavidxu 61144518Sdavidxustatic inline int 62161680Sdavidxu_thr_umutex_trylock(struct umutex *mtx, uint32_t id) 63161680Sdavidxu{ 64161680Sdavidxu if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_UNOWNED, id)) 65161680Sdavidxu return (0); 66161680Sdavidxu if ((mtx->m_flags & UMUTEX_PRIO_PROTECT) == 0) 67161680Sdavidxu return (EBUSY); 68163334Sdavidxu return (__thr_umutex_trylock(mtx)); 69161680Sdavidxu} 70161680Sdavidxu 71161680Sdavidxustatic inline int 72165206Sdavidxu_thr_umutex_trylock2(struct umutex *mtx, uint32_t id) 73165206Sdavidxu{ 74165206Sdavidxu if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_UNOWNED, id)) 75165206Sdavidxu return (0); 76165206Sdavidxu return (EBUSY); 77165206Sdavidxu} 78165206Sdavidxu 79165206Sdavidxustatic inline int 80161680Sdavidxu_thr_umutex_lock(struct umutex *mtx, uint32_t id) 81161680Sdavidxu{ 82161680Sdavidxu if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_UNOWNED, id)) 83161680Sdavidxu return (0); 84163334Sdavidxu return (__thr_umutex_lock(mtx)); 85161680Sdavidxu} 86161680Sdavidxu 87161680Sdavidxustatic inline int 88161680Sdavidxu_thr_umutex_timedlock(struct umutex *mtx, uint32_t id, 89161680Sdavidxu const struct timespec *timeout) 90161680Sdavidxu{ 91161680Sdavidxu if (atomic_cmpset_acq_32(&mtx->m_owner, UMUTEX_UNOWNED, id)) 92161680Sdavidxu return (0); 93163334Sdavidxu return (__thr_umutex_timedlock(mtx, timeout)); 94161680Sdavidxu} 95161680Sdavidxu 96161680Sdavidxustatic inline int 97161680Sdavidxu_thr_umutex_unlock(struct umutex *mtx, uint32_t id) 98161680Sdavidxu{ 99161680Sdavidxu if (atomic_cmpset_rel_32(&mtx->m_owner, id, UMUTEX_UNOWNED)) 100161680Sdavidxu return (0); 101163334Sdavidxu return (__thr_umutex_unlock(mtx)); 102161680Sdavidxu} 103161680Sdavidxu 104177850Sdavidxustatic inline int 105177850Sdavidxu_thr_rwlock_tryrdlock(struct urwlock *rwlock, int flags) 106177850Sdavidxu{ 107177850Sdavidxu int32_t state; 108177850Sdavidxu int32_t wrflags; 109177850Sdavidxu 110177850Sdavidxu if (flags & URWLOCK_PREFER_READER || rwlock->rw_flags & URWLOCK_PREFER_READER) 111177850Sdavidxu wrflags = URWLOCK_WRITE_OWNER; 112177850Sdavidxu else 113177850Sdavidxu wrflags = URWLOCK_WRITE_OWNER | URWLOCK_WRITE_WAITERS; 114177850Sdavidxu state = rwlock->rw_state; 115177850Sdavidxu while (!(state & wrflags)) { 116177850Sdavidxu if (__predict_false(URWLOCK_READER_COUNT(state) == URWLOCK_MAX_READERS)) 117177850Sdavidxu return (EAGAIN); 118177850Sdavidxu if (atomic_cmpset_acq_32(&rwlock->rw_state, state, state + 1)) 119177850Sdavidxu return (0); 120177850Sdavidxu state = rwlock->rw_state; 121177850Sdavidxu } 122177850Sdavidxu 123177850Sdavidxu return (EBUSY); 124177850Sdavidxu} 125177850Sdavidxu 126177850Sdavidxustatic inline int 127177850Sdavidxu_thr_rwlock_trywrlock(struct urwlock *rwlock) 128177850Sdavidxu{ 129177850Sdavidxu int32_t state; 130177850Sdavidxu 131177850Sdavidxu state = rwlock->rw_state; 132177850Sdavidxu while (!(state & URWLOCK_WRITE_OWNER) && URWLOCK_READER_COUNT(state) == 0) { 133177850Sdavidxu if (atomic_cmpset_acq_32(&rwlock->rw_state, state, state | URWLOCK_WRITE_OWNER)) 134177850Sdavidxu return (0); 135177850Sdavidxu state = rwlock->rw_state; 136177850Sdavidxu } 137177850Sdavidxu 138177850Sdavidxu return (EBUSY); 139177850Sdavidxu} 140177850Sdavidxu 141177850Sdavidxustatic inline int 142177850Sdavidxu_thr_rwlock_rdlock(struct urwlock *rwlock, int flags, struct timespec *tsp) 143177850Sdavidxu{ 144177850Sdavidxu if (_thr_rwlock_tryrdlock(rwlock, flags) == 0) 145177850Sdavidxu return (0); 146177850Sdavidxu return (__thr_rwlock_rdlock(rwlock, flags, tsp)); 147177850Sdavidxu} 148177850Sdavidxu 149177850Sdavidxustatic inline int 150177850Sdavidxu_thr_rwlock_wrlock(struct urwlock *rwlock, struct timespec *tsp) 151177850Sdavidxu{ 152177850Sdavidxu if (_thr_rwlock_trywrlock(rwlock) == 0) 153177850Sdavidxu return (0); 154177850Sdavidxu return (__thr_rwlock_wrlock(rwlock, tsp)); 155177850Sdavidxu} 156177850Sdavidxu 157177850Sdavidxustatic inline int 158177850Sdavidxu_thr_rwlock_unlock(struct urwlock *rwlock) 159177850Sdavidxu{ 160177850Sdavidxu int32_t state; 161177850Sdavidxu 162177850Sdavidxu state = rwlock->rw_state; 163177850Sdavidxu if (state & URWLOCK_WRITE_OWNER) { 164177850Sdavidxu if (atomic_cmpset_rel_32(&rwlock->rw_state, URWLOCK_WRITE_OWNER, 0)) 165177850Sdavidxu return (0); 166177850Sdavidxu } else { 167177850Sdavidxu for (;;) { 168177850Sdavidxu if (__predict_false(URWLOCK_READER_COUNT(state) == 0)) 169177850Sdavidxu return (EPERM); 170177850Sdavidxu if (!((state & URWLOCK_WRITE_WAITERS) && URWLOCK_READER_COUNT(state) == 1)) { 171177850Sdavidxu if (atomic_cmpset_rel_32(&rwlock->rw_state, state, state-1)) 172177850Sdavidxu return (0); 173177850Sdavidxu state = rwlock->rw_state; 174177850Sdavidxu } else { 175177850Sdavidxu break; 176177850Sdavidxu } 177177850Sdavidxu } 178177850Sdavidxu } 179177850Sdavidxu return (__thr_rwlock_unlock(rwlock)); 180177850Sdavidxu} 181144518Sdavidxu#endif 182