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-rw-r--r--lib/libpthread/thread/thr_create.c258
1 files changed, 164 insertions, 94 deletions
diff --git a/lib/libpthread/thread/thr_create.c b/lib/libpthread/thread/thr_create.c
index c9f5a42..5a435ca 100644
--- a/lib/libpthread/thread/thr_create.c
+++ b/lib/libpthread/thread/thr_create.c
@@ -50,102 +50,150 @@ int _thread_next_offset = OFF(tle.tqe_next);
int _thread_uniqueid_offset = OFF(uniqueid);
int _thread_state_offset = OFF(state);
int _thread_name_offset = OFF(name);
-int _thread_ctx_offset = OFF(mailbox.tm_context);
+int _thread_ctx_offset = OFF(tmbx.tm_context);
#undef OFF
int _thread_PS_RUNNING_value = PS_RUNNING;
int _thread_PS_DEAD_value = PS_DEAD;
+static int create_stack(struct pthread_attr *pattr);
+static void thread_start(struct pthread *curthread,
+ void *(*start_routine) (void *), void *arg);
+
__weak_reference(_pthread_create, pthread_create);
+/*
+ * 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 = _get_curthread();
- struct itimerval itimer;
- int f_gc = 0;
- int ret = 0;
- 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;
+ struct kse *curkse;
+ struct pthread *curthread, *new_thread;
+ struct kse *kse = NULL;
+ struct kse_group *kseg = NULL;
+ kse_critical_t crit;
+ int i;
+ int ret = 0;
+
+ if (_thr_initial == NULL)
+ _libpthread_init(NULL);
+
+ crit = _kse_critical_enter();
+ curthread = _get_curthread();
+ curkse = curthread->kse;
/* Allocate memory for the thread structure: */
- if ((new_thread = (pthread_t) malloc(sizeof(struct pthread))) == NULL) {
+ if ((new_thread = _thr_alloc(curkse)) == NULL) {
/* Insufficient memory to create a thread: */
ret = EAGAIN;
} else {
+ /* Initialize the thread structure: */
+ memset(new_thread, 0, sizeof(struct pthread));
+
/* Check if default thread attributes are required: */
- if (attr == NULL || *attr == NULL) {
+ if (attr == NULL || *attr == NULL)
/* Use the default thread attributes: */
- pattr = &pthread_attr_default;
- } else {
- pattr = *attr;
+ new_thread->attr = _pthread_attr_default;
+ else
+ new_thread->attr = *(*attr);
+
+ if (create_stack(&new_thread->attr) != 0) {
+ /* Insufficient memory to create a stack: */
+ ret = EAGAIN;
+ _thr_free(curkse, new_thread);
}
- /* Check if a stack was specified in the thread attributes: */
- if ((stack = pattr->stackaddr_attr) != NULL) {
+ else if (((new_thread->attr.flags & PTHREAD_SCOPE_SYSTEM) != 0) &&
+ (((kse = _kse_alloc(curkse)) == NULL)
+ || ((kseg = _kseg_alloc(curkse)) == NULL))) {
+ /* Insufficient memory to create a new KSE/KSEG: */
+ ret = EAGAIN;
+ if (kse != NULL)
+ _kse_free(curkse, kse);
+ if ((new_thread->attr.flags & THR_STACK_USER) == 0) {
+ KSE_LOCK_ACQUIRE(curkse, &_thread_list_lock);
+ _thr_stack_free(&new_thread->attr);
+ KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
+ }
+ _thr_free(curkse, new_thread);
}
- /* Allocate a stack: */
else {
- stack = _thread_stack_alloc(pattr->stacksize_attr,
- pattr->guardsize_attr);
- if (stack == NULL) {
- ret = EAGAIN;
- free(new_thread);
+ if (kseg != NULL) {
+ /* Add the KSE to the KSEG's list of KSEs. */
+ TAILQ_INSERT_HEAD(&kseg->kg_kseq, kse, k_qe);
+ 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;
- /* 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->stack = stack;
new_thread->start_routine = start_routine;
new_thread->arg = arg;
-
new_thread->cancelflags = PTHREAD_CANCEL_ENABLE |
PTHREAD_CANCEL_DEFERRED;
- /*
- * Write a magic value to the thread structure
- * to help identify valid ones:
- */
- new_thread->magic = PTHREAD_MAGIC;
+ /* Initialize the thread for signals: */
+ new_thread->sigmask = curthread->sigmask;
+
+ /* No thread is wanting to join to this one: */
+ new_thread->joiner = NULL;
- /* Initialise the machine context: */
- getcontext(&new_thread->mailbox.tm_context);
- new_thread->mailbox.tm_context.uc_stack.ss_sp =
- new_thread->stack;
- new_thread->mailbox.tm_context.uc_stack.ss_size =
- pattr->stacksize_attr;
- makecontext(&new_thread->mailbox.tm_context,
- _thread_start, 1);
- new_thread->mailbox.tm_udata = (void *)new_thread;
+ /* Initialize the signal frame: */
+ new_thread->curframe = NULL;
- /* Copy the thread attributes: */
- memcpy(&new_thread->attr, pattr, sizeof(struct pthread_attr));
+ /* Initialize the machine context: */
+ THR_GETCONTEXT(&new_thread->tmbx.tm_context);
+ new_thread->tmbx.tm_udata = new_thread;
+ new_thread->tmbx.tm_context.uc_sigmask =
+ new_thread->sigmask;
+ new_thread->tmbx.tm_context.uc_stack.ss_size =
+ new_thread->attr.stacksize_attr;
+ new_thread->tmbx.tm_context.uc_stack.ss_sp =
+ new_thread->attr.stackaddr_attr;
+
+ makecontext(&new_thread->tmbx.tm_context,
+ (void (*)(void))thread_start, 4, new_thread,
+ start_routine, arg);
/*
* Check if this thread is to inherit the scheduling
* attributes from its parent:
*/
- if (new_thread->attr.flags & PTHREAD_INHERIT_SCHED) {
+ if ((new_thread->attr.flags & PTHREAD_INHERIT_SCHED) != 0) {
/* Copy the scheduling attributes: */
new_thread->base_priority =
curthread->base_priority &
- ~PTHREAD_SIGNAL_PRIORITY;
+ ~THR_SIGNAL_PRIORITY;
new_thread->attr.prio =
curthread->base_priority &
- ~PTHREAD_SIGNAL_PRIORITY;
+ ~THR_SIGNAL_PRIORITY;
new_thread->attr.sched_policy =
curthread->attr.sched_policy;
} else {
@@ -160,23 +208,49 @@ _pthread_create(pthread_t * thread, const pthread_attr_t * attr,
new_thread->active_priority = new_thread->base_priority;
new_thread->inherited_priority = 0;
- /* Initialize joiner to NULL (no joiner): */
- new_thread->joiner = NULL;
-
/* Initialize the mutex queue: */
TAILQ_INIT(&new_thread->mutexq);
+ /* Initialize thread locking. */
+ if (_lock_init(&new_thread->lock, LCK_ADAPTIVE,
+ _thr_lock_wait, _thr_lock_wakeup) != 0)
+ PANIC("Cannot initialize thread lock");
+ for (i = 0; i < MAX_THR_LOCKLEVEL; i++) {
+ _lockuser_init(&new_thread->lockusers[i],
+ (void *)new_thread);
+ _LCK_SET_PRIVATE2(&new_thread->lockusers[i],
+ (void *)new_thread);
+ }
+
/* Initialise hooks in the thread structure: */
new_thread->specific = NULL;
new_thread->cleanup = NULL;
new_thread->flags = 0;
new_thread->continuation = NULL;
+ if (new_thread->attr.suspend == THR_CREATE_SUSPENDED)
+ new_thread->state = PS_SUSPENDED;
+ else
+ new_thread->state = PS_RUNNING;
+
/*
- * Defer signals to protect the scheduling queues
- * from access by the signal handler:
+ * System scope threads have their own kse and
+ * kseg. Process scope threads are all hung
+ * off the main process kseg.
*/
- _thread_kern_sig_defer();
+ 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_mbx.km_udata = kse;
+ kse->k_mbx.km_curthread = NULL;
+ }
+ KSE_LOCK_ACQUIRE(curthread->kse, &_thread_list_lock);
/*
* Initialise the unique id which GDB uses to
@@ -184,57 +258,53 @@ _pthread_create(pthread_t * thread, const pthread_attr_t * attr,
*/
new_thread->uniqueid = next_uniqueid++;
- /*
- * 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);
+ THR_LIST_ADD(new_thread);
- if (pattr->suspend == PTHREAD_CREATE_SUSPENDED) {
- new_thread->flags |= PTHREAD_FLAGS_SUSPENDED;
- new_thread->state = PS_SUSPENDED;
- } else {
- new_thread->state = PS_RUNNING;
- PTHREAD_PRIOQ_INSERT_TAIL(new_thread);
- }
+ KSE_LOCK_RELEASE(curthread->kse, &_thread_list_lock);
/*
- * Undefer and handle pending signals, yielding
- * if necessary.
+ * Schedule the new thread starting a new KSEG/KSE
+ * pair if necessary.
*/
- _thread_kern_sig_undefer();
+ _thr_schedule_add(curthread, new_thread);
/* Return a pointer to the thread structure: */
(*thread) = new_thread;
-
- /* Schedule the new user thread: */
- _thread_kern_sched();
-
- /*
- * 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");
-
}
}
+ _kse_critical_leave(crit);
+
+ if ((ret == 0) && (_kse_isthreaded() == 0))
+ _kse_setthreaded(1);
/* Return the status: */
return (ret);
}
-void
-_thread_start(void)
+static int
+create_stack(struct pthread_attr *pattr)
{
- struct pthread *curthread = _get_curthread();
+ int ret;
+ /* Check if a stack was specified in the thread attributes: */
+ if ((pattr->stackaddr_attr) != NULL) {
+ pattr->guardsize_attr = 0;
+ pattr->flags = THR_STACK_USER;
+ ret = 0;
+ }
+ else
+ ret = _thr_stack_alloc(pattr);
+ return (ret);
+}
+
+
+static void
+thread_start(struct pthread *curthread, void *(*start_routine) (void *),
+ void *arg)
+{
/* Run the current thread's start routine with argument: */
- pthread_exit(curthread->start_routine(curthread->arg));
+ pthread_exit(start_routine(arg));
/* This point should never be reached. */
PANIC("Thread has resumed after exit");
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