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/*
* Copyright (c) 1996, 1998, 1999 University of Utah and the Flux Group.
* All rights reserved.
*
* This file is part of the Flux OSKit. The OSKit is free software, also known
* as "open source;" you can redistribute it and/or modify it under the terms
* of the GNU General Public License (GPL), version 2, as published by the Free
* Software Foundation (FSF). To explore alternate licensing terms, contact
* the University of Utah at csl-dist@cs.utah.edu or +1-801-585-3271.
*
* The OSKit is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GPL for more details. You should have
* received a copy of the GPL along with the OSKit; see the file COPYING. If
* not, write to the FSF, 59 Temple Place #330, Boston, MA 02111-1307, USA.
*/
/*
* Internal routines for threads package.
*/
#include <threads/pthread_internal.h>
/*
* This is first routine called for every thread.
*/
void
pthread_start_thread(pthread_thread_t *pthread)
{
/*
* Threads start with the current thread pointer not set yet.
*/
SETCURPTHREAD(pthread);
/*
* All threads start with the schedlock locked.
*/
pthread_unlock(&pthread->schedlock);
/*
* All threads start out with interrupts and preemptions blocked,
* which must be reset.
*/
enable_interrupts();
enable_preemption();
DPRINTF("(%d): P:%p, T:%d, F:%p A:%p\n", THISCPU,
pthread, (int) pthread->tid, pthread->func, pthread->cookie);
/*
* If the function returns a value, it is passed to pthread_exit.
*/
pthread_exit((*pthread->func)(pthread->cookie));
/* NOTREACHED */
}
/*
* The idle thread exists to spin looking for threads to run, and provide
* a place for pthread_delay() to get called so that in usermode CPU time
* is not wildly consumed.
*/
void *
pthread_idle_function(void *arg)
{
DPRINTF("(%d): starting\n", THISCPU);
/*
* The idle thread is run preemption disabled.
*/
disable_preemption();
while (1) {
assert_interrupts_enabled();
assert_preemption_disabled();
pthread_reap_threads();
/*
* If nothing to schedule call the delay function
*/
if (!pthread_sched_reschedule(RESCHED_INTERNAL, 0))
pthread_delay();
}
return 0;
}
/*
* Unblock all the threads in the given queue.
*
* The caller should have locked the Q.
*/
void
pthread_resume_allQ(queue_head_t *queue)
{
pthread_thread_t *pnext;
queue_iterate(queue, pnext, pthread_thread_t *, chain) {
if (pnext == CURPTHREAD())
panic("pthread_resume_allQ");
pthread_sched_setrunnable(pnext);
}
queue_init(queue);
}
/*
* Remove the highest priority item from the Q and return it.
*
* The caller should have locked the Q.
*/
pthread_thread_t *
pthread_dequeue_fromQ(queue_head_t *queue)
{
pthread_thread_t *pnext = 0;
#ifdef DEFAULT_SCHEDULER
pthread_thread_t *ptmp;
int maxpri = -1;
queue_iterate(queue, ptmp, pthread_thread_t *, chain) {
if (ptmp == CURPTHREAD())
panic("pthread_resume_fromQ");
if (ptmp->priority > maxpri) {
maxpri = ptmp->priority;
pnext = ptmp;
}
}
queue_remove(queue, pnext, pthread_thread_t *, chain);
#else
queue_remove_first(queue, pnext, pthread_thread_t *, chain);
#endif
return pnext;
}
/*
* Remove a specific thread from a Q, but only if that thread is really
* on the queue.
*
* The caller should have locked the Q.
*/
pthread_thread_t *
pthread_remove_fromQ(queue_head_t *queue, pthread_thread_t *pthread)
{
pthread_thread_t *ptmp = NULL_THREADPTR;
queue_iterate(queue, ptmp, pthread_thread_t *, chain) {
if (ptmp == CURPTHREAD())
panic("pthread_remove_fromQ");
if (ptmp == pthread) {
queue_remove(queue, ptmp, pthread_thread_t *, chain);
return ptmp;
}
}
return NULL_THREADPTR;
}
void
pthread_lock_panic(pthread_lock_t *lock)
{
panic("spin_lock: "
"Lock 0x%x locked for a long time. Maybe you deadlocked!",
(int) lock);
}
#ifdef THREADS_DEBUG
void
pthread_lock_debug(pthread_lock_t *lock)
{
#ifdef SMP
int i;
for (i = 0; i < 2000000; i++)
#endif
if (spin_try_lock(lock))
return;
pthread_lock_panic(lock);
}
#endif
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