/*
* Copyright (c) 1995-1998 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.
*
* $Id: uthread_create.c,v 1.17 1999/07/11 06:06:52 jasone Exp $
*/
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/mman.h>
#ifdef _THREAD_SAFE
#include <machine/reg.h>
#include <pthread.h>
#include "pthread_private.h"
#include "libc_private.h"
int
pthread_create(pthread_t * thread, const pthread_attr_t * attr,
void *(*start_routine) (void *), void *arg)
{
int f_gc = 0;
int i;
int ret = 0;
int status;
pthread_t gc_thread;
pthread_t new_thread;
pthread_attr_t pattr;
void *stack;
/*
* Locking functions in libc are required when there are
* threads other than the initial thread.
*/
__isthreaded = 1;
/* Allocate memory for the thread structure: */
if ((new_thread = (pthread_t) malloc(sizeof(struct pthread))) == NULL) {
/* Insufficient memory to create a thread: */
ret = EAGAIN;
} else {
/* Check if default thread attributes are required: */
if (attr == NULL || *attr == NULL) {
/* Use the default thread attributes: */
pattr = &pthread_attr_default;
} else {
pattr = *attr;
}
/* Check if a stack was specified in the thread attributes: */
if ((stack = pattr->stackaddr_attr) != NULL) {
}
/* Allocate memory for a default-size stack: */
else if (pattr->stacksize_attr == PTHREAD_STACK_DEFAULT) {
struct stack *spare_stack;
/* Allocate or re-use a default-size stack. */
/*
* Use the garbage collector mutex for synchronization
* of the spare stack list.
*/
if (pthread_mutex_lock(&_gc_mutex) != 0)
PANIC("Cannot lock gc mutex");
if ((spare_stack = SLIST_FIRST(&_stackq)) != NULL) {
/* Use the spare stack. */
SLIST_REMOVE_HEAD(&_stackq, qe);
/* Unlock the garbage collector mutex. */
if (pthread_mutex_unlock(&_gc_mutex) != 0)
PANIC("Cannot unlock gc mutex");
stack = sizeof(struct stack)
+ (void *) spare_stack
- PTHREAD_STACK_DEFAULT;
} else {
/* Unlock the garbage collector mutex. */
if (pthread_mutex_unlock(&_gc_mutex) != 0)
PANIC("Cannot unlock gc mutex");
/* Allocate a new stack. */
stack = _next_stack + PTHREAD_STACK_GUARD;
/*
* Even if stack allocation fails, we don't want
* to try to use this location again, so
* unconditionally decrement _next_stack. Under
* normal operating conditions, the most likely
* reason for an mmap() error is a stack
* overflow of the adjacent thread stack.
*/
_next_stack -= (PTHREAD_STACK_DEFAULT
+ PTHREAD_STACK_GUARD);
/* Red zone: */
if (mmap(_next_stack, PTHREAD_STACK_GUARD, 0,
MAP_ANON, -1, 0) == MAP_FAILED) {
ret = EAGAIN;
free(new_thread);
}
/* Stack: */
else if (mmap(stack,
PTHREAD_STACK_DEFAULT,
PROT_READ | PROT_WRITE,
#ifdef __i386__
MAP_STACK,
#else
MAP_ANON,
#endif
-1, 0) == MAP_FAILED) {
ret = EAGAIN;
munmap(_next_stack,
PTHREAD_STACK_GUARD);
free(new_thread);
}
}
}
/*
* The user wants a stack of a particular size. Lets hope they
* really know what they want, and simply malloc the stack.
*/
else if ((stack = (void *) malloc(pattr->stacksize_attr))
== NULL) {
/* Insufficient memory to create a thread: */
ret = EAGAIN;
free(new_thread);
}
/* Check for errors: */
if (ret != 0) {
} else {
/* Initialise the thread structure: */
memset(new_thread, 0, sizeof(struct pthread));
new_thread->slice_usec = -1;
new_thread->sig_saved = 0;
new_thread->stack = stack;
new_thread->start_routine = start_routine;
new_thread->arg = arg;
/*
* Write a magic value to the thread structure
* to help identify valid ones:
*/
new_thread->magic = PTHREAD_MAGIC;
/* Initialise the thread for signals: */
new_thread->sigmask = _thread_run->sigmask;
/* Initialise the jump buffer: */
setjmp(new_thread->saved_jmp_buf);
/*
* Set up new stack frame so that it looks like it
* returned from a longjmp() to the beginning of
* _thread_start().
*/
#if defined(__FreeBSD__)
#if defined(__alpha__)
new_thread->saved_jmp_buf[0]._jb[2] = (long) _thread_start;
new_thread->saved_jmp_buf[0]._jb[4 + R_RA] = 0;
new_thread->saved_jmp_buf[0]._jb[4 + R_T12] = (long) _thread_start;
#else
new_thread->saved_jmp_buf[0]._jb[0] = (long) _thread_start;
#endif
#elif defined(__NetBSD__)
#if defined(__alpha__)
new_thread->saved_jmp_buf[2] = (long) _thread_start;
new_thread->saved_jmp_buf[4 + R_RA] = 0;
new_thread->saved_jmp_buf[4 + R_T12] = (long) _thread_start;
#else
new_thread->saved_jmp_buf[0] = (long) _thread_start;
#endif
#else
#error "Don't recognize this operating system!"
#endif
/* The stack starts high and builds down: */
#if defined(__FreeBSD__)
#if defined(__alpha__)
new_thread->saved_jmp_buf[0]._jb[4 + R_SP] = (long) new_thread->stack + pattr->stacksize_attr - sizeof(double);
#else
new_thread->saved_jmp_buf[0]._jb[2] = (int) (new_thread->stack + pattr->stacksize_attr - sizeof(double));
#endif
#elif defined(__NetBSD__)
#if defined(__alpha__)
new_thread->saved_jmp_buf[4 + R_SP] = (long) new_thread->stack + pattr->stacksize_attr - sizeof(double);
#else
new_thread->saved_jmp_buf[2] = (long) new_thread->stack + pattr->stacksize_attr - sizeof(double);
#endif
#else
#error "Don't recognize this operating system!"
#endif
/* Copy the thread attributes: */
memcpy(&new_thread->attr, pattr, sizeof(struct pthread_attr));
/*
* Check if this thread is to inherit the scheduling
* attributes from its parent:
*/
if (new_thread->attr.flags & PTHREAD_INHERIT_SCHED) {
/* Copy the scheduling attributes: */
new_thread->base_priority
= _thread_run->base_priority;
new_thread->attr.prio
= _thread_run->base_priority;
new_thread->attr.sched_policy
= _thread_run->attr.sched_policy;
} else {
/*
* Use just the thread priority, leaving the
* other scheduling attributes as their
* default values:
*/
new_thread->base_priority
= new_thread->attr.prio;
}
new_thread->active_priority = new_thread->base_priority;
new_thread->inherited_priority = 0;
/* Initialise the join queue for the new thread: */
TAILQ_INIT(&(new_thread->join_queue));
/* Initialize the mutex queue: */
TAILQ_INIT(&new_thread->mutexq);
/* Initialise hooks in the thread structure: */
new_thread->specific_data = NULL;
new_thread->cleanup = NULL;
new_thread->flags = 0;
new_thread->poll_data.nfds = 0;
new_thread->poll_data.fds = NULL;
/*
* Defer signals to protect the scheduling queues
* from access by the signal handler:
*/
_thread_kern_sig_defer();
/*
* Check if the garbage collector thread
* needs to be started.
*/
f_gc = (TAILQ_FIRST(&_thread_list) == _thread_initial);
/* Add the thread to the linked list of all threads: */
TAILQ_INSERT_HEAD(&_thread_list, new_thread, tle);
if (pattr->suspend == PTHREAD_CREATE_SUSPENDED) {
new_thread->state = PS_SUSPENDED;
PTHREAD_WAITQ_INSERT(new_thread);
} else {
new_thread->state = PS_RUNNING;
PTHREAD_PRIOQ_INSERT_TAIL(new_thread);
}
/*
* Undefer and handle pending signals, yielding
* if necessary.
*/
_thread_kern_sig_undefer();
/* Return a pointer to the thread structure: */
(*thread) = new_thread;
/* Schedule the new user thread: */
_thread_kern_sched(NULL);
/*
* Start a garbage collector thread
* if necessary.
*/
if (f_gc && pthread_create(&gc_thread,NULL,
_thread_gc,NULL) != 0)
PANIC("Can't create gc thread");
}
}
/* Return the status: */
return (ret);
}
void
_thread_start(void)
{
/* We just left the scheduler via longjmp: */
_thread_kern_in_sched = 0;
/* Run the current thread's start routine with argument: */
pthread_exit(_thread_run->start_routine(_thread_run->arg));
/* This point should never be reached. */
PANIC("Thread has resumed after exit");
}
#endif
