pthreads_user.c

Netscape NSPR库源码

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 
 * The contents of this file are subject to the Mozilla Public
 * License Version 1.1 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.mozilla.org/MPL/
 * 
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 * 
 * The Original Code is the Netscape Portable Runtime (NSPR).
 * 
 * The Initial Developer of the Original Code is Netscape
 * Communications Corporation.  Portions created by Netscape are 
 * Copyright (C) 1998-2000 Netscape Communications Corporation.  All
 * Rights Reserved.
 * 
 * Contributor(s):
 * 
 * Alternatively, the contents of this file may be used under the
 * terms of the GNU General Public License Version 2 or later (the
 * "GPL"), in which case the provisions of the GPL are applicable 
 * instead of those above.  If you wish to allow use of your 
 * version of this file only under the terms of the GPL and not to
 * allow others to use your version of this file under the MPL,
 * indicate your decision by deleting the provisions above and
 * replace them with the notice and other provisions required by
 * the GPL.  If you do not delete the provisions above, a recipient
 * may use your version of this file under either the MPL or the
 * GPL.
 */

#include "primpl.h"
#include <sys/types.h>
#include <unistd.h>
#include <signal.h>
#include <pthread.h>


sigset_t ints_off;
pthread_mutex_t	_pr_heapLock;
pthread_key_t current_thread_key;
pthread_key_t current_cpu_key;
pthread_key_t last_thread_key;
pthread_key_t intsoff_key;


PRInt32 _pr_md_pthreads_created, _pr_md_pthreads_failed;
PRInt32 _pr_md_pthreads = 1;

void _MD_EarlyInit(void)
{
extern PRInt32 _nspr_noclock;

	if (pthread_key_create(&current_thread_key, NULL) != 0) {
		perror("pthread_key_create failed");
		exit(1);
	}
	if (pthread_key_create(&current_cpu_key, NULL) != 0) {
		perror("pthread_key_create failed");
		exit(1);
	}
	if (pthread_key_create(&last_thread_key, NULL) != 0) {
		perror("pthread_key_create failed");
		exit(1);
	}
	if (pthread_key_create(&intsoff_key, NULL) != 0) {
		perror("pthread_key_create failed");
		exit(1);
	}

	sigemptyset(&ints_off);
	sigaddset(&ints_off, SIGALRM);
	sigaddset(&ints_off, SIGIO);
	sigaddset(&ints_off, SIGCLD);

	/*
	 * disable clock interrupts
	 */
	_nspr_noclock = 1;

}

void _MD_InitLocks()
{
	if (pthread_mutex_init(&_pr_heapLock, NULL) != 0) {
		perror("pthread_mutex_init failed");
		exit(1);
	}
}

PR_IMPLEMENT(void) _MD_FREE_LOCK(struct _MDLock *lockp)
{
	PRIntn _is;
	PRThread *me = _PR_MD_CURRENT_THREAD();

	if (me && !_PR_IS_NATIVE_THREAD(me))
		_PR_INTSOFF(_is); 
	pthread_mutex_destroy(&lockp->mutex);
	if (me && !_PR_IS_NATIVE_THREAD(me))
		_PR_FAST_INTSON(_is);
}



PR_IMPLEMENT(PRStatus) _MD_NEW_LOCK(struct _MDLock *lockp)
{
    PRStatus rv;
    PRIntn is;
    PRThread *me = _PR_MD_CURRENT_THREAD();	

	if (me && !_PR_IS_NATIVE_THREAD(me))
		_PR_INTSOFF(is);
	rv = pthread_mutex_init(&lockp->mutex, NULL);
	if (me && !_PR_IS_NATIVE_THREAD(me))
		_PR_FAST_INTSON(is);
	return (rv == 0) ? PR_SUCCESS : PR_FAILURE;
}


PRWord *_MD_HomeGCRegisters(PRThread *t, int isCurrent, int *np)
{
    if (isCurrent) {
	(void) setjmp(CONTEXT(t));
    }
    *np = sizeof(CONTEXT(t)) / sizeof(PRWord);
    return (PRWord *) CONTEXT(t);
}

PR_IMPLEMENT(void)
_MD_SetPriority(_MDThread *thread, PRThreadPriority newPri)
{
	/*
	 * XXX - to be implemented
	 */
    return;
}

PR_IMPLEMENT(PRStatus) _MD_InitThread(struct PRThread *thread)
{
    struct sigaction sigact;

    if (thread->flags & _PR_GLOBAL_SCOPE) {
        thread->md.pthread = pthread_self();
#if 0
		/*
		 * set up SIGUSR1 handler; this is used to save state
		 * during PR_SuspendAll
		 */
		sigact.sa_handler = save_context_and_block;
		sigact.sa_flags = SA_RESTART;
		/*
		 * Must mask clock interrupts
		 */
		sigact.sa_mask = timer_set;
		sigaction(SIGUSR1, &sigact, 0);
#endif
    }

    return PR_SUCCESS;
}

PR_IMPLEMENT(void) _MD_ExitThread(struct PRThread *thread)
{
    if (thread->flags & _PR_GLOBAL_SCOPE) {
        _MD_CLEAN_THREAD(thread);
        _MD_SET_CURRENT_THREAD(NULL);
    }
}

PR_IMPLEMENT(void) _MD_CleanThread(struct PRThread *thread)
{
    if (thread->flags & _PR_GLOBAL_SCOPE) {
		pthread_mutex_destroy(&thread->md.pthread_mutex);
		pthread_cond_destroy(&thread->md.pthread_cond);
    }
}

PR_IMPLEMENT(void) _MD_SuspendThread(struct PRThread *thread)
{
    PRInt32 rv;

    PR_ASSERT((thread->flags & _PR_GLOBAL_SCOPE) &&
        _PR_IS_GCABLE_THREAD(thread));
#if 0
	thread->md.suspending_id = getpid();
	rv = kill(thread->md.id, SIGUSR1);
	PR_ASSERT(rv == 0);
	/*
	 * now, block the current thread/cpu until woken up by the suspended
	 * thread from it's SIGUSR1 signal handler
	 */
	blockproc(getpid());
#endif
}

PR_IMPLEMENT(void) _MD_ResumeThread(struct PRThread *thread)
{
    PRInt32 rv;

    PR_ASSERT((thread->flags & _PR_GLOBAL_SCOPE) &&
        _PR_IS_GCABLE_THREAD(thread));
#if 0
    rv = unblockproc(thread->md.id);
#endif
}

PR_IMPLEMENT(void) _MD_SuspendCPU(struct _PRCPU *thread)
{
    PRInt32 rv;

#if 0
	cpu->md.suspending_id = getpid();
	rv = kill(cpu->md.id, SIGUSR1);
	PR_ASSERT(rv == 0);
	/*
	 * now, block the current thread/cpu until woken up by the suspended
	 * thread from it's SIGUSR1 signal handler
	 */
	blockproc(getpid());
#endif
}

PR_IMPLEMENT(void) _MD_ResumeCPU(struct _PRCPU *thread)
{
#if 0
	unblockproc(cpu->md.id);
#endif
}


#define PT_NANOPERMICRO 1000UL
#define PT_BILLION 1000000000UL

PR_IMPLEMENT(PRStatus)
_pt_wait(PRThread *thread, PRIntervalTime timeout)
{
int rv;
struct timeval now;
struct timespec tmo;
PRUint32 ticks = PR_TicksPerSecond();


	if (timeout != PR_INTERVAL_NO_TIMEOUT) {
		tmo.tv_sec = timeout / ticks;
		tmo.tv_nsec = timeout - (tmo.tv_sec * ticks);
		tmo.tv_nsec = PR_IntervalToMicroseconds(PT_NANOPERMICRO *
											tmo.tv_nsec);

		/* pthreads wants this in absolute time, off we go ... */
		(void)GETTIMEOFDAY(&now);
		/* that one's usecs, this one's nsecs - grrrr! */
		tmo.tv_sec += now.tv_sec;
		tmo.tv_nsec += (PT_NANOPERMICRO * now.tv_usec);
		tmo.tv_sec += tmo.tv_nsec / PT_BILLION;
		tmo.tv_nsec %= PT_BILLION;
	}

	pthread_mutex_lock(&thread->md.pthread_mutex);
	thread->md.wait--;
	if (thread->md.wait < 0) {
		if (timeout != PR_INTERVAL_NO_TIMEOUT) {
			rv = pthread_cond_timedwait(&thread->md.pthread_cond,
					&thread->md.pthread_mutex, &tmo);
        }
		else
			rv = pthread_cond_wait(&thread->md.pthread_cond,
					&thread->md.pthread_mutex);
		if (rv != 0) {
			thread->md.wait++;
		}
	} else
		rv = 0;
	pthread_mutex_unlock(&thread->md.pthread_mutex);

	return (rv == 0) ? PR_SUCCESS : PR_FAILURE;
}

PR_IMPLEMENT(PRStatus)
_MD_wait(PRThread *thread, PRIntervalTime ticks)
{
    if ( thread->flags & _PR_GLOBAL_SCOPE ) {
		_MD_CHECK_FOR_EXIT();
        if (_pt_wait(thread, ticks) == PR_FAILURE) {
	    	_MD_CHECK_FOR_EXIT();
            /*
             * wait timed out
             */
            _PR_THREAD_LOCK(thread);
            if (thread->wait.cvar) {
                /*
                 * The thread will remove itself from the waitQ
                 * of the cvar in _PR_WaitCondVar
                 */
                thread->wait.cvar = NULL;
                thread->state =  _PR_RUNNING;
                _PR_THREAD_UNLOCK(thread);
            }  else {
        		_pt_wait(thread, PR_INTERVAL_NO_TIMEOUT);
                _PR_THREAD_UNLOCK(thread);
            }
        }
    } else {
		_PR_MD_SWITCH_CONTEXT(thread);
    }
    return PR_SUCCESS;
}

PR_IMPLEMENT(PRStatus)
_MD_WakeupWaiter(PRThread *thread)
{
    PRThread *me = _PR_MD_CURRENT_THREAD();
    PRInt32 pid, rv;
    PRIntn is;

	PR_ASSERT(_pr_md_idle_cpus >= 0);
    if (thread == NULL) {
		if (_pr_md_idle_cpus)
        	_MD_Wakeup_CPUs();
    } else if (!_PR_IS_NATIVE_THREAD(thread)) {
		/*
		 * If the thread is on my cpu's runq there is no need to
		 * wakeup any cpus
		 */
		if (!_PR_IS_NATIVE_THREAD(me)) {
			if (me->cpu != thread->cpu) {
				if (_pr_md_idle_cpus)
        			_MD_Wakeup_CPUs();
			}
		} else {
			if (_pr_md_idle_cpus)
        		_MD_Wakeup_CPUs();
		}
    } else {
		PR_ASSERT(_PR_IS_NATIVE_THREAD(thread));
		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_INTSOFF(is);

		pthread_mutex_lock(&thread->md.pthread_mutex);
		thread->md.wait++;
		rv = pthread_cond_signal(&thread->md.pthread_cond);
		PR_ASSERT(rv == 0);
		pthread_mutex_unlock(&thread->md.pthread_mutex);

		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_FAST_INTSON(is);
    } 
    return PR_SUCCESS;
}

/* These functions should not be called for AIX */
PR_IMPLEMENT(void)
_MD_YIELD(void)
{
    PR_NOT_REACHED("_MD_YIELD should not be called for AIX.");
}

PR_IMPLEMENT(PRStatus)
_MD_CreateThread(
    PRThread *thread,
    void (*start) (void *),
    PRThreadPriority priority,
    PRThreadScope scope,
    PRThreadState state,
    PRUint32 stackSize)
{
    PRIntn is;
    int rv;
	PRThread *me = _PR_MD_CURRENT_THREAD();	
	pthread_attr_t attr;

	if (!_PR_IS_NATIVE_THREAD(me))
		_PR_INTSOFF(is);

	if (pthread_mutex_init(&thread->md.pthread_mutex, NULL) != 0) {
		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_FAST_INTSON(is);
        return PR_FAILURE;
	}

	if (pthread_cond_init(&thread->md.pthread_cond, NULL) != 0) {
		pthread_mutex_destroy(&thread->md.pthread_mutex);
		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_FAST_INTSON(is);
        return PR_FAILURE;
	}
    thread->flags |= _PR_GLOBAL_SCOPE;

	pthread_attr_init(&attr); /* initialize attr with default attributes */
	if (pthread_attr_setstacksize(&attr, (size_t) stackSize) != 0) {
		pthread_mutex_destroy(&thread->md.pthread_mutex);
		pthread_cond_destroy(&thread->md.pthread_cond);
		pthread_attr_destroy(&attr);
		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_FAST_INTSON(is);
        return PR_FAILURE;
	}

	thread->md.wait = 0;
    rv = pthread_create(&thread->md.pthread, &attr, start, (void *)thread);
    if (0 == rv) {
        _MD_ATOMIC_INCREMENT(&_pr_md_pthreads_created);
        _MD_ATOMIC_INCREMENT(&_pr_md_pthreads);
		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_FAST_INTSON(is);
        return PR_SUCCESS;
    } else {
		pthread_mutex_destroy(&thread->md.pthread_mutex);
		pthread_cond_destroy(&thread->md.pthread_cond);
		pthread_attr_destroy(&attr);
        _MD_ATOMIC_INCREMENT(&_pr_md_pthreads_failed);
		if (!_PR_IS_NATIVE_THREAD(me))
			_PR_FAST_INTSON(is);
        PR_SetError(PR_INSUFFICIENT_RESOURCES_ERROR, rv);
        return PR_FAILURE;
    }
}

PR_IMPLEMENT(void)
_MD_InitRunningCPU(struct _PRCPU *cpu)
{
    extern int _pr_md_pipefd[2];

    _MD_unix_init_running_cpu(cpu);
    cpu->md.pthread = pthread_self();
	if (_pr_md_pipefd[0] >= 0) {
    	_PR_IOQ_MAX_OSFD(cpu) = _pr_md_pipefd[0];
#ifndef _PR_USE_POLL
    	FD_SET(_pr_md_pipefd[0], &_PR_FD_READ_SET(cpu));
#endif
	}
}


void
_MD_CleanupBeforeExit(void)
{
#if 0
    extern PRInt32    _pr_cpus_exit;

	_pr_irix_exit_now = 1;
    if (_pr_numCPU > 1) {
        /*
         * Set a global flag, and wakeup all cpus which will notice the flag
         * and exit.
         */
        _pr_cpus_exit = getpid();
        _MD_Wakeup_CPUs();
        while(_pr_numCPU > 1) {
            _PR_WAIT_SEM(_pr_irix_exit_sem);
            _pr_numCPU--;
        }
    }
    /*
     * cause global threads on the recycle list to exit
     */
     _PR_DEADQ_LOCK;
     if (_PR_NUM_DEADNATIVE != 0) {
	PRThread *thread;
    	PRCList *ptr;

        ptr = _PR_DEADNATIVEQ.next;
        while( ptr != &_PR_DEADNATIVEQ ) {
        	thread = _PR_THREAD_PTR(ptr);
		_MD_CVAR_POST_SEM(thread);
                ptr = ptr->next;
        } 
     }
     _PR_DEADQ_UNLOCK;
     while(_PR_NUM_DEADNATIVE > 1) {
	_PR_WAIT_SEM(_pr_irix_exit_sem);
	_PR_DEC_DEADNATIVE;
     }
#endif
}