/*
* Threaded process initialization.
*
* This is only called under two conditions:
*
* 1) Some thread routines have detected that the library hasn't yet
* been initialized (_thr_initial == NULL && curthread == NULL), or
*
* 2) An explicit call to reinitialize after a fork (indicated
* by curthread != NULL)
*/
void
_libpthread_init(struct pthread *curthread)
{
int fd;
/* Check if this function has already been called: */
if ((_thr_initial != NULL) && (curthread == NULL))
/* Only initialize the threaded application once. */
return;
/*
* Make gcc quiescent about {,libgcc_}references not being
* referenced:
*/
if ((references[0] == NULL) || (libgcc_references[0] == NULL))
PANIC("Failed loading mandatory references in _thread_init");
/* Pull debug symbols in for static binary */
_thread_state_running = PS_RUNNING;
/*
* Check the size of the jump table to make sure it is preset
* with the correct number of entries.
*/
if (sizeof(jmp_table) != (sizeof(pthread_func_t) * PJT_MAX * 2))
PANIC("Thread jump table not properly initialized");
memcpy(__thr_jtable, jmp_table, sizeof(jmp_table));
/*
* Check for the special case of this process running as
* or in place of init as pid = 1:
*/
if ((_thr_pid = getpid()) == 1) {
/*
* Setup a new session for this process which is
* assumed to be running as root.
*/
if (setsid() == -1)
PANIC("Can't set session ID");
if (revoke(_PATH_CONSOLE) != 0)
PANIC("Can't revoke console");
if ((fd = __sys_open(_PATH_CONSOLE, O_RDWR)) < 0)
PANIC("Can't open console");
if (setlogin("root") == -1)
PANIC("Can't set login to root");
if (__sys_ioctl(fd, TIOCSCTTY, (char *) NULL) == -1)
PANIC("Can't set controlling terminal");
}
/* Initialize pthread private data. */
init_private();
_kse_init();
/* Initialize the initial kse and kseg. */
_kse_initial = _kse_alloc(NULL, _thread_scope_system > 0);
if (_kse_initial == NULL)
PANIC("Can't allocate initial kse.");
_kse_initial->k_kseg = _kseg_alloc(NULL);
if (_kse_initial->k_kseg == NULL)
PANIC("Can't allocate initial kseg.");
_kse_initial->k_kseg->kg_flags |= KGF_SINGLE_THREAD;
_kse_initial->k_schedq = &_kse_initial->k_kseg->kg_schedq;
TAILQ_INSERT_TAIL(&_kse_initial->k_kseg->kg_kseq, _kse_initial, k_kgqe);
_kse_initial->k_kseg->kg_ksecount = 1;
/* Set the initial thread. */
if (curthread == NULL) {
/* Create and initialize the initial thread. */
curthread = _thr_alloc(NULL);
if (curthread == NULL)
PANIC("Can't allocate initial thread");
_thr_initial = curthread;
init_main_thread(curthread);
} else {
/*
* The initial thread is the current thread. It is
* assumed that the current thread is already initialized
* because it is left over from a fork().
*/
_thr_initial = curthread;
}
_kse_initial->k_kseg->kg_threadcount = 0;
_thr_initial->kse = _kse_initial;
_thr_initial->kseg = _kse_initial->k_kseg;
_thr_initial->active = 1;
/*
* Add the thread to the thread list and to the KSEG's thread
* queue.
*/
THR_LIST_ADD(_thr_initial);
KSEG_THRQ_ADD(_kse_initial->k_kseg, _thr_initial);
/* Setup the KSE/thread specific data for the current KSE/thread. */
_thr_initial->kse->k_curthread = _thr_initial;
_kcb_set(_thr_initial->kse->k_kcb);
_tcb_set(_thr_initial->kse->k_kcb, _thr_initial->tcb);
_thr_initial->kse->k_flags |= KF_INITIALIZED;
_thr_signal_init();
_kse_critical_leave(&_thr_initial->tcb->tcb_tmbx);
/*
* activate threaded mode as soon as possible if we are
* being debugged
*/
if (_libkse_debug)
_kse_setthreaded(1);
}
/*
* Some notes on new thread creation and first time initializion
* to enable multi-threading.
*
* There are basically two things that need to be done.
*
* 1) The internal library variables must be initialized.
* 2) Upcalls need to be enabled to allow multiple threads
* to be run.
*
* The first may be done as a result of other pthread functions
* being called. When _thr_initial is null, _libpthread_init is
* called to initialize the internal variables; this also creates
* or sets the initial thread. It'd be nice to automatically
* have _libpthread_init called on program execution so we don't
* have to have checks throughout the library.
*
* The second part is only triggered by the creation of the first
* thread (other than the initial/main thread). If the thread
* being created is a scope system thread, then a new KSE/KSEG
* pair needs to be allocated. Also, if upcalls haven't been
* enabled on the initial thread's KSE, they must be now that
* there is more than one thread; this could be delayed until
* the initial KSEG has more than one thread.
*/
int
_pthread_create(pthread_t * thread, const pthread_attr_t * attr,
void *(*start_routine) (void *), void *arg)
{
struct pthread *curthread, *new_thread;
struct kse *kse = NULL;
struct kse_group *kseg = NULL;
kse_critical_t crit;
int ret = 0;
if (_thr_initial == NULL)
_libpthread_init(NULL);
/*
* Turn on threaded mode, if failed, it is unnecessary to
* do further work.
*/
if (_kse_isthreaded() == 0 && _kse_setthreaded(1)) {
return (EAGAIN);
}
curthread = _get_curthread();
/*
* Allocate memory for the thread structure.
* Some functions use malloc, so don't put it
* in a critical region.
*/
if ((new_thread = _thr_alloc(curthread)) == 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: */
new_thread->attr = _pthread_attr_default;
else {
new_thread->attr = *(*attr);
if ((*attr)->sched_inherit == PTHREAD_INHERIT_SCHED) {
/* inherit scheduling contention scop */
if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM;
else
new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM;
/*
* scheduling policy and scheduling parameters will be
* inherited in following code.
*/
}
}
if (_thread_scope_system > 0)
new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM;
else if ((_thread_scope_system < 0)
&& (thread != &_thr_sig_daemon))
new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM;
if (create_stack(&new_thread->attr) != 0) {
/* Insufficient memory to create a stack: */
ret = EAGAIN;
_thr_free(curthread, new_thread);
}
else if (((new_thread->attr.flags & PTHREAD_SCOPE_SYSTEM) != 0) &&
(((kse = _kse_alloc(curthread, 1)) == NULL)
|| ((kseg = _kseg_alloc(curthread)) == NULL))) {
/* Insufficient memory to create a new KSE/KSEG: */
ret = EAGAIN;
if (kse != NULL) {
kse->k_kcb->kcb_kmbx.km_flags |= KMF_DONE;
_kse_free(curthread, kse);
}
free_stack(&new_thread->attr);
_thr_free(curthread, new_thread);
}
else {
if (kseg != NULL) {
/* Add the KSE to the KSEG's list of KSEs. */
TAILQ_INSERT_HEAD(&kseg->kg_kseq, kse, k_kgqe);
kseg->kg_ksecount = 1;
kse->k_kseg = kseg;
kse->k_schedq = &kseg->kg_schedq;
}
/*
* Write a magic value to the thread structure
* to help identify valid ones:
*/
new_thread->magic = THR_MAGIC;
new_thread->slice_usec = -1;
new_thread->start_routine = start_routine;
new_thread->arg = arg;
new_thread->cancelflags = PTHREAD_CANCEL_ENABLE |
PTHREAD_CANCEL_DEFERRED;
/* No thread is wanting to join to this one: */
new_thread->joiner = NULL;
/*
* Initialize the machine context.
* Enter a critical region to get consistent context.
*/
crit = _kse_critical_enter();
THR_GETCONTEXT(&new_thread->tcb->tcb_tmbx.tm_context);
/* Initialize the thread for signals: */
new_thread->sigmask = curthread->sigmask;
_kse_critical_leave(crit);
new_thread->tcb->tcb_tmbx.tm_udata = new_thread;
new_thread->tcb->tcb_tmbx.tm_context.uc_sigmask =
new_thread->sigmask;
new_thread->tcb->tcb_tmbx.tm_context.uc_stack.ss_size =
new_thread->attr.stacksize_attr;
new_thread->tcb->tcb_tmbx.tm_context.uc_stack.ss_sp =
new_thread->attr.stackaddr_attr;
makecontext(&new_thread->tcb->tcb_tmbx.tm_context,
(void (*)(void))thread_start, 3, new_thread,
start_routine, arg);
/*
* Check if this thread is to inherit the scheduling
* attributes from its parent:
*/
if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) {
/*
* Copy the scheduling attributes.
* Lock the scheduling lock to get consistent
* scheduling parameters.
*/
THR_SCHED_LOCK(curthread, curthread);
new_thread->base_priority =
curthread->base_priority &
~THR_SIGNAL_PRIORITY;
new_thread->attr.prio =
curthread->base_priority &
~THR_SIGNAL_PRIORITY;
new_thread->attr.sched_policy =
curthread->attr.sched_policy;
THR_SCHED_UNLOCK(curthread, curthread);
} 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;
/* Initialize the mutex queue: */
TAILQ_INIT(&new_thread->mutexq);
/* Initialise hooks in the thread structure: */
new_thread->specific = NULL;
new_thread->specific_data_count = 0;
new_thread->cleanup = NULL;
new_thread->flags = 0;
new_thread->tlflags = 0;
new_thread->sigbackout = NULL;
new_thread->continuation = NULL;
new_thread->wakeup_time.tv_sec = -1;
new_thread->lock_switch = 0;
sigemptyset(&new_thread->sigpend);
new_thread->check_pending = 0;
new_thread->locklevel = 0;
new_thread->rdlock_count = 0;
new_thread->sigstk.ss_sp = 0;
new_thread->sigstk.ss_size = 0;
new_thread->sigstk.ss_flags = SS_DISABLE;
new_thread->oldsigmask = NULL;
if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) {
new_thread->state = PS_SUSPENDED;
new_thread->flags = THR_FLAGS_SUSPENDED;
}
else
new_thread->state = PS_RUNNING;
/*
* System scope threads have their own kse and
* kseg. Process scope threads are all hung
* off the main process kseg.
*/
if ((new_thread->attr.flags & PTHREAD_SCOPE_SYSTEM) == 0) {
new_thread->kseg = _kse_initial->k_kseg;
new_thread->kse = _kse_initial;
}
else {
kse->k_curthread = NULL;
kse->k_kseg->kg_flags |= KGF_SINGLE_THREAD;
new_thread->kse = kse;
new_thread->kseg = kse->k_kseg;
kse->k_kcb->kcb_kmbx.km_udata = kse;
kse->k_kcb->kcb_kmbx.km_curthread = NULL;
}
/*
* Schedule the new thread starting a new KSEG/KSE
* pair if necessary.
*/
ret = _thr_schedule_add(curthread, new_thread);
if (ret != 0)
free_thread(curthread, new_thread);
else {
/* Return a pointer to the thread structure: */
(*thread) = new_thread;
}
}
}
/* Return the status: */
return (ret);
}
