0807c44cdd
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
/*-
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* Copyright (c) 2007 Stephan Uphoff <ups@FreeBSD.org>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the author nor the names of any co-contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* $FreeBSD$
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*/
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#ifndef _SYS__RMLOCK_H_
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#define _SYS__RMLOCK_H_
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/*
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* Mostly reader/occasional writer lock.
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*/
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LIST_HEAD(rmpriolist,rm_priotracker);
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struct rm_queue {
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struct rm_queue *volatile rmq_next;
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struct rm_queue *volatile rmq_prev;
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};
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struct rmlock {
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struct lock_object lock_object;
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volatile cpuset_t rm_writecpus;
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LIST_HEAD(,rm_priotracker) rm_activeReaders;
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union {
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struct lock_object _rm_wlock_object;
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struct mtx _rm_lock_mtx;
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struct sx _rm_lock_sx;
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} _rm_lock;
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};
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#define rm_wlock_object _rm_lock._rm_wlock_object
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#define rm_lock_mtx _rm_lock._rm_lock_mtx
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#define rm_lock_sx _rm_lock._rm_lock_sx
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struct rm_priotracker {
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struct rm_queue rmp_cpuQueue; /* Must be first */
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struct rmlock *rmp_rmlock;
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struct thread *rmp_thread;
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int rmp_flags;
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LIST_ENTRY(rm_priotracker) rmp_qentry;
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};
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#endif /* !_SYS__RMLOCK_H_ */
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