/*
* Internal implementation of semaphores
*/
int
_sem_wait(sem_t sem, int tryonly, const struct timespec *abstime,
int *delayed_cancel)
{
void *ident = (void *)&sem->waitcount;
int r;
if (sem->shared)
ident = SHARED_IDENT;
_spinlock(&sem->lock);
if (sem->value) {
sem->value--;
r = 0;
} else if (tryonly) {
r = EAGAIN;
} else {
sem->waitcount++;
do {
r = __thrsleep(ident, CLOCK_REALTIME |
_USING_TICKETS, abstime, &sem->lock.ticket,
delayed_cancel);
_spinlock(&sem->lock);
/* ignore interruptions other than cancelation */
if (r == EINTR && (delayed_cancel == NULL ||
*delayed_cancel == 0))
r = 0;
} while (r == 0 && sem->value == 0);
sem->waitcount--;
if (r == 0)
sem->value--;
}
_spinunlock(&sem->lock);
return (r);
}
/*
* Internal implementation of semaphores
*/
int
_sem_wait(sem_t sem, int tryonly, const struct timespec *abstime,
int *delayed_cancel)
{
int r;
_spinlock(&sem->lock);
if (sem->value) {
sem->value--;
r = 0;
} else if (tryonly) {
r = EAGAIN;
} else {
sem->waitcount++;
do {
r = __thrsleep(&sem->waitcount, CLOCK_REALTIME,
abstime, &sem->lock, delayed_cancel);
_spinlock(&sem->lock);
/* ignore interruptions other than cancelation */
if (r == EINTR && (delayed_cancel == NULL ||
*delayed_cancel == 0))
r = 0;
} while (r == 0 && sem->value == 0);
sem->waitcount--;
if (r == 0)
sem->value--;
}
_spinunlock(&sem->lock);
return (r);
}
static void
_rthread_clearflag(pthread_t thread, int flag)
{
_spinlock(&thread->flags_lock);
thread->flags &= ~flag;
_spinunlock(&thread->flags_lock);
}
void free_recvframe_queue(_queue *pframequeue, _queue *pfree_recv_queue)
{
union recv_frame *precvframe;
_list *plist, *phead;
_func_enter_;
_spinlock(&pframequeue->lock);
phead = get_list_head(pframequeue);
plist = get_next(phead);
while(end_of_queue_search(phead, plist) == _FALSE)
{
precvframe = LIST_CONTAINOR(plist, union recv_frame, u);
plist = get_next(plist);
//list_delete(&precvframe->u.hdr.list); // will do this in free_recvframe()
free_recvframe(precvframe, pfree_recv_queue);
}
_spinunlock(&pframequeue->lock);
_func_exit_;
}
static void
_rthread_setflag(pthread_t thread, int flag)
{
_spinlock(&thread->flags_lock);
thread->flags |= flag;
_spinunlock(&thread->flags_lock);
}
void
(flockfile)(FILE * fp)
{
int idx = file_idx(fp);
struct file_lock *p;
pthread_t self = pthread_self();
/* Lock the hash table: */
_spinlock(&hash_lock);
/* Get a pointer to any existing lock for the file: */
if ((p = find_lock(idx, fp)) == NULL) {
/*
* The file is not locked, so this thread can
* grab the lock:
*/
do_lock(idx, fp);
/*
* The file is already locked, so check if the
* running thread is the owner:
*/
} else if (p->owner == self) {
/*
* The running thread is already the
* owner, so increment the count of
* the number of times it has locked
* the file:
*/
p->count++;
} else {
/*
* The file is locked for another thread.
* Append this thread to the queue of
* threads waiting on the lock.
*/
TAILQ_INSERT_TAIL(&p->lockers,self,waiting);
while (p->owner != self) {
__thrsleep(self, 0 | _USING_TICKETS, NULL,
&hash_lock.ticket, NULL);
_spinlock(&hash_lock);
}
}
/* Unlock the hash table: */
_spinunlock(&hash_lock);
}
int
pthread_cond_signal(pthread_cond_t *condp)
{
pthread_cond_t cond;
struct pthread_mutex *mutex;
pthread_t thread;
int wakeup;
/* uninitialized? Then there's obviously no one waiting! */
if (!*condp)
return 0;
cond = *condp;
_rthread_debug(5, "%p: cond_signal %p,%p\n", (void *)pthread_self(),
(void *)cond, (void *)cond->mutex);
_spinlock(&cond->lock);
thread = TAILQ_FIRST(&cond->waiters);
if (thread == NULL) {
assert(cond->mutex == NULL);
_spinunlock(&cond->lock);
return (0);
}
assert(thread->blocking_cond == cond);
TAILQ_REMOVE(&cond->waiters, thread, waiting);
thread->blocking_cond = NULL;
mutex = cond->mutex;
assert(mutex != NULL);
if (TAILQ_EMPTY(&cond->waiters))
cond->mutex = NULL;
/* link locks to prevent race with timedwait */
_spinlock(&mutex->lock);
_spinunlock(&cond->lock);
wakeup = mutex->owner == NULL && TAILQ_EMPTY(&mutex->lockers);
if (wakeup)
mutex->owner = thread;
else
TAILQ_INSERT_TAIL(&mutex->lockers, thread, waiting);
_spinunlock(&mutex->lock);
if (wakeup)
__thrwakeup(thread, 1);
return (0);
}
/*
* for ld.so
*/
void
_thread_dl_lock(int t)
{
if(t)
_spinunlock(&dl_lock);
else
_spinlock(&dl_lock);
}
void
_rthread_bind_lock(int what)
{
static _spinlock_lock_t lock = _SPINLOCK_UNLOCKED;
if (what == 0)
_spinlock(&lock);
else
_spinunlock(&lock);
}
void
_thread_tag_lock(void **tag)
{
struct thread_tag *t;
if(*tag == nil)
_thread_tag_init(tag);
t = *tag;
_spinlock(&t->l);
}
/*
* compat debug stuff
*/
void
_thread_dump_info(void)
{
pthread_t thread;
_spinlock(&_thread_lock);
LIST_FOREACH(thread, &_thread_list, threads)
printf("thread %d flags %d name %s\n",
thread->tid, thread->flags, thread->name);
_spinunlock(&_thread_lock);
}
static void
_rthread_start(void *v)
{
pthread_t thread = v;
void *retval;
/* ensure parent returns from rfork, sets up tid */
_spinlock(&_thread_lock);
_spinunlock(&_thread_lock);
retval = thread->fn(thread->arg);
pthread_exit(retval);
}
int
pthread_mutex_unlock(pthread_mutex_t *mutexp)
{
pthread_t self = pthread_self();
struct pthread_mutex *mutex = (struct pthread_mutex *)*mutexp;
_rthread_debug(5, "%p: mutex_unlock %p\n", (void *)self,
(void *)mutex);
if (mutex == NULL)
#if PTHREAD_MUTEX_DEFAULT == PTHREAD_MUTEX_ERRORCHECK
return (EPERM);
#elif PTHREAD_MUTEX_DEFAULT == PTHREAD_MUTEX_NORMAL
return(0);
#else
abort();
#endif
if (mutex->owner != self) {
if (mutex->type == PTHREAD_MUTEX_ERRORCHECK ||
mutex->type == PTHREAD_MUTEX_RECURSIVE)
return (EPERM);
else {
/*
* For mutex type NORMAL our undefined behavior for
* unlocking an unlocked mutex is to succeed without
* error. All other undefined behaviors are to
* abort() immediately.
*/
if (mutex->owner == NULL &&
mutex->type == PTHREAD_MUTEX_NORMAL)
return (0);
else
abort();
}
}
if (--mutex->count == 0) {
pthread_t next;
_spinlock(&mutex->lock);
mutex->owner = next = TAILQ_FIRST(&mutex->lockers);
if (next != NULL)
TAILQ_REMOVE(&mutex->lockers, next, waiting);
_spinunlock(&mutex->lock);
if (next != NULL)
__thrwakeup(next, 1);
}
return (0);
}
/* always increment count */
int
_sem_post(sem_t sem)
{
int rv = 0;
_spinlock(&sem->lock);
sem->value++;
if (sem->waitcount) {
__thrwakeup(&sem->waitcount, 1);
rv = 1;
}
_spinunlock(&sem->lock);
return (rv);
}
/*
* real pthread functions
*/
pthread_t
pthread_self(void)
{
pthread_t thread;
if (!_threads_ready)
if (_rthread_init())
return (NULL);
_spinlock(&_thread_lock);
thread = _rthread_findself();
_spinunlock(&_thread_lock);
return (thread);
}
void
_rthread_free_stack(struct stack *stack)
{
if (stack->len == RTHREAD_STACK_SIZE_DEF + stack->guardsize &&
stack->guardsize == _rthread_attr_default.guard_size) {
_spinlock(&def_stacks_lock);
SLIST_INSERT_HEAD(&def_stacks, stack, link);
_spinunlock(&def_stacks_lock);
} else {
/* unmap the storage unless it was application allocated */
if (stack->guardsize != 1)
munmap(stack->base, stack->len);
free(stack);
}
}
int
(ftrylockfile)(FILE * fp)
{
int ret = -1;
int idx = file_idx(fp);
struct file_lock *p;
/* Lock the hash table: */
_spinlock(&hash_lock);
/* Get a pointer to any existing lock for the file: */
if ((p = find_lock(idx, fp)) == NULL) {
/*
* The file is not locked, so this thread can
* grab the lock:
*/
p = do_lock(idx, fp);
/*
* The file is already locked, so check if the
* running thread is the owner:
*/
} else if (p->owner == pthread_self()) {
/*
* The running thread is already the
* owner, so increment the count of
* the number of times it has locked
* the file:
*/
p->count++;
} else {
/*
* The file is locked for another thread,
* so this try fails.
*/
p = NULL;
}
/* Unlock the hash table: */
_spinunlock(&hash_lock);
/* Check if the lock was obtained: */
if (p != NULL)
/* Return success: */
ret = 0;
return (ret);
}
int
sem_getvalue(sem_t *semp, int *sval)
{
sem_t sem;
if (!semp || !(sem = *semp)) {
errno = EINVAL;
return (-1);
}
_spinlock(&sem->lock);
*sval = sem->value;
_spinunlock(&sem->lock);
return (0);
}
sint _enqueue_cmd(_queue *queue, struct cmd_obj *obj)
{
_func_enter_;
if (obj == NULL)
goto exit;
_spinlock(&(queue->lock));
list_insert_tail(&(obj->list),&(queue->queue));
_spinunlock(&(queue->lock));
exit:
_func_exit_;
return _SUCCESS;
}
/*
* for libc
*/
static void
_thread_tag_init(void **tag)
{
struct thread_tag *t;
_spinlock(&tag_lock);
if(*tag == nil) {
t = malloc(sizeof (*t));
if(t != nil) {
memset(&t->l, 0, sizeof(t->l));
t->key = nextkey++;
*tag = t;
}
}
_spinunlock(&tag_lock);
}
int
pthread_spin_lock(pthread_spinlock_t *lock)
{
pthread_t self = pthread_self();
pthread_spinlock_t l;
if (lock == NULL || *lock == NULL)
return (EINVAL);
l = *lock;
if (l->owner == self)
return (EDEADLK);
_spinlock(&l->lock);
l->owner = self;
return (0);
}
struct cmd_obj *_dequeue_cmd(_queue *queue)
{
struct cmd_obj *obj;
_func_enter_;
_spinlock(&(queue->lock));
if (is_list_empty(&(queue->queue)))
obj = NULL;
else
{
obj = LIST_CONTAINOR(get_next(&(queue->queue)), struct cmd_obj, list);
list_delete(&obj->list);
}
_spinunlock(&(queue->lock));
_func_exit_;
return obj;
}
/* always increment count */
int
_sem_post(sem_t sem)
{
void *ident = (void *)&sem->waitcount;
int rv = 0;
if (sem->shared)
ident = SHARED_IDENT;
_spinlock(&sem->lock);
sem->value++;
if (sem->waitcount) {
__thrwakeup(ident, 1);
rv = 1;
}
_spinunlock(&sem->lock);
return (rv);
}
int
pthread_detach(pthread_t thread)
{
int rc = 0;
_spinlock(&thread->flags_lock);
if (thread->flags & THREAD_DETACHED) {
rc = EINVAL;
_spinunlock(&thread->flags_lock);
} else if (thread->flags & THREAD_DONE) {
_spinunlock(&thread->flags_lock);
_rthread_free(thread);
} else {
thread->flags |= THREAD_DETACHED;
_spinunlock(&thread->flags_lock);
}
_rthread_reaper();
return (rc);
}
static void *
_thread_tag_lookup(struct thread_tag *tag, int size)
{
struct thread_tag *t;
void *p;
_spinlock(&tag->l);
for(t = thread_tag_store; t != nil; t = t->next)
if(t->key == tag->key)
break;
if(t == nil) {
p = malloc(size);
if(p == nil) {
_spinunlock(&tag->l);
return nil;
}
_thread_tag_insert(tag, p);
}
_spinunlock(&tag->l);
return tag->data;
}
void
(funlockfile)(FILE * fp)
{
int idx = file_idx(fp);
struct file_lock *p;
/* Lock the hash table: */
_spinlock(&hash_lock);
/*
* Get a pointer to the lock for the file and check that
* the running thread is the one with the lock:
*/
if ((p = find_lock(idx, fp)) != NULL && p->owner == pthread_self()) {
/*
* Check if this thread has locked the FILE
* more than once:
*/
if (--p->count == 0) {
/* Get the new owner of the lock: */
if ((p->owner = TAILQ_FIRST(&p->lockers)) != NULL) {
/* Pop the thread off the queue: */
TAILQ_REMOVE(&p->lockers,p->owner,waiting);
/*
* This is the first lock for the new
* owner:
*/
p->count = 1;
__thrwakeup(p->owner, 1);
}
}
}
/* Unlock the hash table: */
_spinunlock(&hash_lock);
}
void
pthread_exit(void *retval)
{
struct rthread_cleanup_fn *clfn;
pid_t tid;
struct stack *stack;
pthread_t thread = pthread_self();
thread->retval = retval;
for (clfn = thread->cleanup_fns; clfn; ) {
struct rthread_cleanup_fn *oclfn = clfn;
clfn = clfn->next;
oclfn->fn(oclfn->arg);
free(oclfn);
}
_rthread_tls_destructors(thread);
_spinlock(&_thread_lock);
LIST_REMOVE(thread, threads);
_spinunlock(&_thread_lock);
_sem_post(&thread->donesem);
stack = thread->stack;
tid = thread->tid;
if (thread->flags & THREAD_DETACHED)
_rthread_free(thread);
else
_rthread_setflag(thread, THREAD_DONE);
if (tid != _initial_thread.tid)
_rthread_add_to_reaper(tid, stack);
_rthread_reaper();
threxit(0);
for(;;);
}
static int
_rthread_mutex_lock(pthread_mutex_t *mutexp, int trywait,
const struct timespec *abstime)
{
struct pthread_mutex *mutex;
pthread_t self = pthread_self();
int ret = 0;
/*
* If the mutex is statically initialized, perform the dynamic
* initialization. Note: _thread_mutex_lock() in libc requires
* _rthread_mutex_lock() to perform the mutex init when *mutexp
* is NULL.
*/
if (*mutexp == NULL) {
_spinlock(&static_init_lock);
if (*mutexp == NULL)
ret = pthread_mutex_init(mutexp, NULL);
_spinunlock(&static_init_lock);
if (ret != 0)
return (EINVAL);
}
mutex = (struct pthread_mutex *)*mutexp;
_rthread_debug(5, "%p: mutex_lock %p\n", (void *)self, (void *)mutex);
_spinlock(&mutex->lock);
if (mutex->owner == NULL && TAILQ_EMPTY(&mutex->lockers)) {
assert(mutex->count == 0);
mutex->owner = self;
} else if (mutex->owner == self) {
assert(mutex->count > 0);
/* already owner? handle recursive behavior */
if (mutex->type != PTHREAD_MUTEX_RECURSIVE)
{
if (trywait ||
mutex->type == PTHREAD_MUTEX_ERRORCHECK) {
_spinunlock(&mutex->lock);
return (trywait ? EBUSY : EDEADLK);
}
/* self-deadlock is disallowed by strict */
if (mutex->type == PTHREAD_MUTEX_STRICT_NP &&
abstime == NULL)
abort();
/* self-deadlock, possibly until timeout */
while (__thrsleep(self, CLOCK_REALTIME |
_USING_TICKETS, abstime,
&mutex->lock.ticket, NULL) != EWOULDBLOCK)
_spinlock(&mutex->lock);
return (ETIMEDOUT);
}
if (mutex->count == INT_MAX) {
_spinunlock(&mutex->lock);
return (EAGAIN);
}
} else if (trywait) {
/* try failed */
_spinunlock(&mutex->lock);
return (EBUSY);
} else {
/* add to the wait queue and block until at the head */
TAILQ_INSERT_TAIL(&mutex->lockers, self, waiting);
while (mutex->owner != self) {
ret = __thrsleep(self, CLOCK_REALTIME | _USING_TICKETS,
abstime, &mutex->lock.ticket, NULL);
_spinlock(&mutex->lock);
assert(mutex->owner != NULL);
if (ret == EWOULDBLOCK) {
if (mutex->owner == self)
break;
TAILQ_REMOVE(&mutex->lockers, self, waiting);
_spinunlock(&mutex->lock);
return (ETIMEDOUT);
}
}
}
mutex->count++;
_spinunlock(&mutex->lock);
return (0);
}
int
pthread_cond_broadcast(pthread_cond_t *condp)
{
pthread_cond_t cond;
struct pthread_mutex *mutex;
pthread_t thread;
pthread_t p;
int wakeup;
/* uninitialized? Then there's obviously no one waiting! */
if (!*condp)
return 0;
cond = *condp;
_rthread_debug(5, "%p: cond_broadcast %p,%p\n", (void *)pthread_self(),
(void *)cond, (void *)cond->mutex);
_spinlock(&cond->lock);
thread = TAILQ_FIRST(&cond->waiters);
if (thread == NULL) {
assert(cond->mutex == NULL);
_spinunlock(&cond->lock);
return (0);
}
mutex = cond->mutex;
assert(mutex != NULL);
/* walk the list, clearing the "blocked on condvar" pointer */
p = thread;
do
p->blocking_cond = NULL;
while ((p = TAILQ_NEXT(p, waiting)) != NULL);
/*
* We want to transfer all the threads from the condvar's list
* to the mutex's list. The TAILQ_* macros don't let us do that
* efficiently, so this is direct list surgery. Pay attention!
*/
/* 1) attach the first thread to the end of the mutex's list */
_spinlock(&mutex->lock);
wakeup = mutex->owner == NULL && TAILQ_EMPTY(&mutex->lockers);
thread->waiting.tqe_prev = mutex->lockers.tqh_last;
*(mutex->lockers.tqh_last) = thread;
/* 2) fix up the end pointer for the mutex's list */
mutex->lockers.tqh_last = cond->waiters.tqh_last;
if (wakeup) {
TAILQ_REMOVE(&mutex->lockers, thread, waiting);
mutex->owner = thread;
_spinunlock(&mutex->lock);
__thrwakeup(thread, 1);
} else
_spinunlock(&mutex->lock);
/* 3) reset the condvar's list and mutex pointer */
TAILQ_INIT(&cond->waiters);
assert(cond->mutex != NULL);
cond->mutex = NULL;
_spinunlock(&cond->lock);
return (0);
}
int
pthread_cond_wait(pthread_cond_t *condp, pthread_mutex_t *mutexp)
{
pthread_cond_t cond;
struct pthread_mutex *mutex = (struct pthread_mutex *)*mutexp;
struct tib *tib = TIB_GET();
pthread_t self = tib->tib_thread;
pthread_t next;
int mutex_count;
int canceled = 0;
int error;
PREP_CANCEL_POINT(tib);
if (!*condp)
if ((error = pthread_cond_init(condp, NULL)))
return (error);
cond = *condp;
_rthread_debug(5, "%p: cond_wait %p,%p\n", (void *)self,
(void *)cond, (void *)mutex);
if (mutex == NULL)
#if PTHREAD_MUTEX_DEFAULT == PTHREAD_MUTEX_ERRORCHECK
return (EPERM);
#else
abort();
#endif
if (mutex->owner != self) {
if (mutex->type == PTHREAD_MUTEX_ERRORCHECK)
return (EPERM);
else
abort();
}
ENTER_DELAYED_CANCEL_POINT(tib, self);
_spinlock(&cond->lock);
/* mark the condvar as being associated with this mutex */
if (cond->mutex == NULL) {
cond->mutex = mutex;
assert(TAILQ_EMPTY(&cond->waiters));
} else if (cond->mutex != mutex) {
assert(cond->mutex == mutex);
_spinunlock(&cond->lock);
LEAVE_CANCEL_POINT_INNER(tib, 1);
return (EINVAL);
} else
assert(! TAILQ_EMPTY(&cond->waiters));
/* snag the count in case this is a recursive mutex */
mutex_count = mutex->count;
/* transfer from the mutex queue to the condvar queue */
_spinlock(&mutex->lock);
self->blocking_cond = cond;
TAILQ_INSERT_TAIL(&cond->waiters, self, waiting);
_spinunlock(&cond->lock);
/* wake the next guy blocked on the mutex */
mutex->count = 0;
mutex->owner = next = TAILQ_FIRST(&mutex->lockers);
if (next != NULL) {
TAILQ_REMOVE(&mutex->lockers, next, waiting);
__thrwakeup(next, 1);
}
/* wait until we're the owner of the mutex again */
while (mutex->owner != self) {
error = __thrsleep(self, 0 | _USING_TICKETS, NULL,
&mutex->lock.ticket, &self->delayed_cancel);
/*
* If we took a normal signal (not from
* cancellation) then we should just go back to
* sleep without changing state (timeouts, etc).
*/
if (error == EINTR && (tib->tib_canceled == 0 ||
(tib->tib_cantcancel & CANCEL_DISABLED))) {
_spinlock(&mutex->lock);
continue;
}
/*
* The remaining reasons for waking up (normal
* wakeup and cancellation) all mean that we won't
* be staying in the condvar queue and we'll no
* longer be cancelable.
*/
LEAVE_CANCEL_POINT_INNER(tib, 0);
/*
* If we're no longer in the condvar's queue then
* we're just waiting for mutex ownership. Need
* cond->lock here to prevent race with cond_signal().
*/
_spinlock(&cond->lock);
if (self->blocking_cond == NULL) {
_spinunlock(&cond->lock);
_spinlock(&mutex->lock);
continue;
}
assert(self->blocking_cond == cond);
/* if canceled, make note of that */
if (error == EINTR)
canceled = 1;
/* transfer between the queues */
TAILQ_REMOVE(&cond->waiters, self, waiting);
assert(mutex == cond->mutex);
if (TAILQ_EMPTY(&cond->waiters))
cond->mutex = NULL;
self->blocking_cond = NULL;
_spinunlock(&cond->lock);
_spinlock(&mutex->lock);
/* mutex unlocked right now? */
if (mutex->owner == NULL &&
TAILQ_EMPTY(&mutex->lockers)) {
assert(mutex->count == 0);
mutex->owner = self;
break;
}
TAILQ_INSERT_TAIL(&mutex->lockers, self, waiting);
}
/* restore the mutex's count */
mutex->count = mutex_count;
_spinunlock(&mutex->lock);
LEAVE_CANCEL_POINT_INNER(tib, canceled);
return (0);
}
