diff options
Diffstat (limited to 'lib/libpthread/sys/lock.h')
| -rw-r--r-- | lib/libpthread/sys/lock.h | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/lib/libpthread/sys/lock.h b/lib/libpthread/sys/lock.h new file mode 100644 index 0000000..eeb7286 --- /dev/null +++ b/lib/libpthread/sys/lock.h @@ -0,0 +1,89 @@ +/* + * Copyright (c) 2001 Daniel Eischen <deischen@FreeBSD.org>. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD$ + */ + +#ifndef _LOCK_H_ +#define _LOCK_H_ + +struct lockreq; +struct lockuser; +struct lock; + +enum lock_type { + LCK_DEFAULT = 0x0000, /* default is FIFO spin locks */ + LCK_PRIORITY = 0x0001, + LCK_ADAPTIVE = 0x0002 /* call user-supplied handlers */ +}; + +typedef void lock_handler_t(struct lock *, struct lockuser *); + +struct lock { + struct lockreq *l_head; + struct lockreq *l_tail; /* only used for priority locks */ + enum lock_type l_type; + lock_handler_t *l_wait; /* only used for adaptive locks */ + lock_handler_t *l_wakeup; /* only used for adaptive locks */ +}; + +/* Try to make this >= CACHELINESIZE */ +struct lockreq { + volatile long lr_locked; /* lock granted = 0, busy otherwise */ + struct lockuser *lr_watcher; /* only used for priority locks */ + struct lockuser *lr_owner; /* only used for priority locks */ + long lr_waiting; /* non-zero when wakeup needed */ +}; + +struct lockuser { + struct lockreq *lu_myreq; /* request to give up/trade */ + struct lockreq *lu_watchreq; /* watch this request */ + int lu_priority; /* only used for priority locks */ + void *lu_private1; /* private{1,2} are initialized to */ + void *lu_private2; /* NULL and can be used by caller */ +#define lu_private lu_private1 +}; + +#define _LCK_INITIALIZER(lck_req) { &lck_req, NULL, LCK_DEFAULT, \ + NULL, NULL } +#define _LCK_REQUEST_INITIALIZER { 0, NULL, NULL, 0 } + +#define _LCK_BUSY(lu) ((lu)->lu_watchreq->lr_locked != 0) +#define _LCK_GRANTED(lu) ((lu)->lu_watchreq->lr_locked == 0) + +#define _LCK_SET_PRIVATE(lu, p) (lu)->lu_private = (void *)(p) +#define _LCK_GET_PRIVATE(lu) (lu)->lu_private +#define _LCK_SET_PRIVATE2(lu, p) (lu)->lu_private2 = (void *)(p) +#define _LCK_GET_PRIVATE2(lu) (lu)->lu_private2 + +void _lock_destroy(struct lock *); +int _lock_init(struct lock *, enum lock_type, + lock_handler_t *, lock_handler_t *); +int _lockuser_init(struct lockuser *lu, void *priv); +void _lockuser_destroy(struct lockuser *lu); +void _lock_acquire(struct lock *, struct lockuser *, int); +void _lock_release(struct lock *, struct lockuser *); + +#endif |
