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/*
* Copyright (c) 2003 Daniel Eischen <deischen@freebsd.org>
* Copyright (c) 1998 John Birrell <jb@cimlogic.com.au>.
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. 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 JOHN BIRRELL 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.
*
* $FreeBSD$
*/
#include <errno.h>
#include <pthread.h>
#include "thr_private.h"
/*
* Find a thread in the linked list of active threads and add a reference
* to it. Threads with positive reference counts will not be deallocated
* until all references are released.
*/
int
_thr_ref_add(struct pthread *curthread, struct pthread *thread,
int include_dead)
{
kse_critical_t crit;
struct pthread *pthread;
struct kse *curkse;
if (thread == NULL)
/* Invalid thread: */
return (EINVAL);
crit = _kse_critical_enter();
curkse = _get_curkse();
KSE_LOCK_ACQUIRE(curkse, &_thread_list_lock);
pthread = _thr_hash_find(thread);
if (pthread) {
if ((include_dead == 0) &&
((pthread->state == PS_DEAD) ||
((pthread->state == PS_DEADLOCK) ||
((pthread->flags & THR_FLAGS_EXITING) != 0))))
pthread = NULL;
else {
pthread->refcount++;
if (curthread != NULL)
curthread->critical_count++;
}
}
KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
_kse_critical_leave(crit);
/* Return zero if the thread exists: */
return ((pthread != NULL) ? 0 : ESRCH);
}
void
_thr_ref_delete(struct pthread *curthread, struct pthread *thread)
{
kse_critical_t crit;
struct kse *curkse;
if (thread != NULL) {
crit = _kse_critical_enter();
curkse = _get_curkse();
KSE_LOCK_ACQUIRE(curkse, &_thread_list_lock);
thread->refcount--;
if (curthread != NULL)
curthread->critical_count--;
if ((thread->refcount == 0) &&
(thread->flags & THR_FLAGS_GC_SAFE) != 0)
THR_GCLIST_ADD(thread);
KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
_kse_critical_leave(crit);
}
}
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