cd32bd7ad1
provided by Isilon. - Add an rm_assert() supporting various lock assertions similar to other locking primitives. Because rmlocks track readers the assertions are always fully accurate unlike rw_assert() and sx_assert(). - Flesh out the lock class methods for rmlocks to support sleeping via condvars and rm_sleep() (but only while holding write locks), rmlock details in 'show lock' in DDB, and the lc_owner method used by dtrace. - Add an internal destroyed cookie so that API functions can assert that an rmlock is not destroyed. - Make use of rm_assert() to add various assertions to the API (e.g. to assert locks are held when an unlock routine is called). - Give RM_SLEEPABLE locks their own lock class and always use the rmlock's own lock_object with WITNESS. - Use THREAD_NO_SLEEPING() / THREAD_SLEEPING_OK() to disallow sleeping while holding a read lock on an rmlock. Submitted by: andre Obtained from: EMC/Isilon
70 lines
2.4 KiB
C
70 lines
2.4 KiB
C
/*-
|
|
* Copyright (c) 2007 Stephan Uphoff <ups@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.
|
|
* 3. Neither the name of the author nor the names of any co-contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 _SYS__RMLOCK_H_
|
|
#define _SYS__RMLOCK_H_
|
|
|
|
/*
|
|
* Mostly reader/occasional writer lock.
|
|
*/
|
|
|
|
LIST_HEAD(rmpriolist,rm_priotracker);
|
|
|
|
struct rm_queue {
|
|
struct rm_queue *volatile rmq_next;
|
|
struct rm_queue *volatile rmq_prev;
|
|
};
|
|
|
|
struct rmlock {
|
|
struct lock_object lock_object;
|
|
volatile cpuset_t rm_writecpus;
|
|
LIST_HEAD(,rm_priotracker) rm_activeReaders;
|
|
union {
|
|
struct lock_object _rm_wlock_object;
|
|
struct mtx _rm_lock_mtx;
|
|
struct sx _rm_lock_sx;
|
|
} _rm_lock;
|
|
};
|
|
|
|
#define rm_wlock_object _rm_lock._rm_wlock_object
|
|
#define rm_lock_mtx _rm_lock._rm_lock_mtx
|
|
#define rm_lock_sx _rm_lock._rm_lock_sx
|
|
|
|
struct rm_priotracker {
|
|
struct rm_queue rmp_cpuQueue; /* Must be first */
|
|
struct rmlock *rmp_rmlock;
|
|
struct thread *rmp_thread;
|
|
int rmp_flags;
|
|
LIST_ENTRY(rm_priotracker) rmp_qentry;
|
|
};
|
|
|
|
#endif /* !_SYS__RMLOCK_H_ */
|