void
_thr_free(struct pthread *curthread, struct pthread *thread)
{
DBG_MSG("Freeing thread %p\n", thread);
if (thread->name) {
free(thread->name);
thread->name = NULL;
}
/*
* Always free tcb, as we only know it is part of RTLD TLS
* block, but don't know its detail and can not assume how
* it works, so better to avoid caching it here.
*/
if (curthread != NULL) {
THR_LOCK_ACQUIRE(curthread, &tcb_lock);
_tcb_dtor(thread->tcb);
THR_LOCK_RELEASE(curthread, &tcb_lock);
} else {
_tcb_dtor(thread->tcb);
}
thread->tcb = NULL;
if ((curthread == NULL) || (free_thread_count >= MAX_CACHED_THREADS)) {
thr_destroy(curthread, thread);
} else {
/*
* Add the thread to the free thread list, this also avoids
* pthread id is reused too quickly, may help some buggy apps.
*/
THR_LOCK_ACQUIRE(curthread, &free_thread_lock);
TAILQ_INSERT_TAIL(&free_threadq, thread, tle);
free_thread_count++;
THR_LOCK_RELEASE(curthread, &free_thread_lock);
}
}
int
_pthread_key_create(pthread_key_t *key, void (*destructor) (void *))
{
struct pthread *curthread;
int i;
if (_thr_initial == NULL)
_libpthread_init(NULL);
curthread = _get_curthread();
/* Lock the key table: */
THR_LOCK_ACQUIRE(curthread, &_keytable_lock);
for (i = 0; i < PTHREAD_KEYS_MAX; i++) {
if (_thread_keytable[i].allocated == 0) {
_thread_keytable[i].allocated = 1;
_thread_keytable[i].destructor = destructor;
_thread_keytable[i].seqno++;
/* Unlock the key table: */
THR_LOCK_RELEASE(curthread, &_keytable_lock);
*key = i;
return (0);
}
}
/* Unlock the key table: */
THR_LOCK_RELEASE(curthread, &_keytable_lock);
return (EAGAIN);
}
void
_thread_cleanupspecific(void)
{
struct pthread *curthread = _get_curthread();
const_key_destructor_t destructor;
const void *data = NULL;
int key;
int i;
if (curthread->specific == NULL)
return;
/* Lock the key table: */
THR_LOCK_ACQUIRE(curthread, &_keytable_lock);
for (i = 0; (i < PTHREAD_DESTRUCTOR_ITERATIONS) &&
(curthread->specific_data_count > 0); i++) {
for (key = 0; (key < PTHREAD_KEYS_MAX) &&
(curthread->specific_data_count > 0); key++) {
destructor = NULL;
if (_thread_keytable[key].allocated &&
(curthread->specific[key].data != NULL)) {
if (curthread->specific[key].seqno ==
_thread_keytable[key].seqno) {
data = curthread->specific[key].data;
destructor = (const_key_destructor_t)
_thread_keytable[key].destructor;
}
curthread->specific[key].data = NULL;
curthread->specific_data_count--;
}
/*
* If there is a destructore, call it
* with the key table entry unlocked:
*/
if (destructor != NULL) {
/*
* Don't hold the lock while calling the
* destructor:
*/
THR_LOCK_RELEASE(curthread, &_keytable_lock);
destructor(data);
THR_LOCK_ACQUIRE(curthread, &_keytable_lock);
}
}
}
THR_LOCK_RELEASE(curthread, &_keytable_lock);
free(curthread->specific);
curthread->specific = NULL;
if (curthread->specific_data_count > 0)
stderr_debug("Thread %p has exited with leftover "
"thread-specific data after %d destructor iterations\n",
curthread, PTHREAD_DESTRUCTOR_ITERATIONS);
}
static void
cond_wait_backout(void *arg)
{
struct pthread *curthread = (struct pthread *)arg;
pthread_cond_t cond;
cond = curthread->data.cond;
if (cond != NULL) {
/* Lock the condition variable structure: */
THR_LOCK_ACQUIRE(curthread, &cond->c_lock);
/* Process according to condition variable type: */
switch (cond->c_type) {
/* Fast condition variable: */
case COND_TYPE_FAST:
cond_queue_remove(cond, curthread);
/* Check for no more waiters: */
if (TAILQ_EMPTY(&cond->c_queue))
cond->c_mutex = NULL;
break;
default:
break;
}
/* Unlock the condition variable structure: */
THR_LOCK_RELEASE(curthread, &cond->c_lock);
}
/* No need to call this again. */
curthread->sigbackout = NULL;
}
/*
* Allocate wake-address, the memory area is never freed after
* allocated, this becauses threads may be referencing it.
*/
struct wake_addr *
_thr_alloc_wake_addr(void)
{
struct pthread *curthread;
struct wake_addr *p;
if (_thr_initial == NULL) {
return &default_wake_addr;
}
curthread = _get_curthread();
THR_LOCK_ACQUIRE(curthread, &addr_lock);
if (wake_addr_head == NULL) {
unsigned i;
unsigned pagesize = getpagesize();
struct wake_addr *pp = (struct wake_addr *)
mmap(NULL, getpagesize(), PROT_READ|PROT_WRITE,
MAP_ANON|MAP_PRIVATE, -1, 0);
for (i = 1; i < pagesize/sizeof(struct wake_addr); ++i)
pp[i].link = &pp[i+1];
pp[i-1].link = NULL;
wake_addr_head = &pp[1];
p = &pp[0];
} else {
p = wake_addr_head;
wake_addr_head = p->link;
}
THR_LOCK_RELEASE(curthread, &addr_lock);
p->value = 0;
return (p);
}
int
_pthread_mutex_destroy(pthread_mutex_t *mutex)
{
struct pthread *curthread = _get_curthread();
pthread_mutex_t m;
int ret = 0;
if (mutex == NULL || *mutex == NULL)
ret = EINVAL;
else {
/* Lock the mutex structure: */
THR_LOCK_ACQUIRE(curthread, &(*mutex)->m_lock);
/*
* Check to see if this mutex is in use:
*/
if (((*mutex)->m_owner != NULL) ||
(!TAILQ_EMPTY(&(*mutex)->m_queue)) ||
((*mutex)->m_refcount != 0)) {
ret = EBUSY;
/* Unlock the mutex structure: */
THR_LOCK_RELEASE(curthread, &(*mutex)->m_lock);
} else {
/*
* Save a pointer to the mutex so it can be free'd
* and set the caller's pointer to NULL:
*/
m = *mutex;
*mutex = NULL;
/* Unlock the mutex structure: */
THR_LOCK_RELEASE(curthread, &m->m_lock);
/*
* Free the memory allocated for the mutex
* structure:
*/
MUTEX_ASSERT_NOT_OWNED(m);
MUTEX_DESTROY(m);
}
}
/* Return the completion status: */
return (ret);
}
void
_thr_release_wake_addr(struct wake_addr *wa)
{
struct pthread *curthread = _get_curthread();
if (wa == &default_wake_addr)
return;
THR_LOCK_ACQUIRE(curthread, &addr_lock);
wa->link = wake_addr_head;
wake_addr_head = wa;
THR_LOCK_RELEASE(curthread, &addr_lock);
}
struct pthread *
_thr_alloc(struct pthread *curthread)
{
struct pthread *thread = NULL;
struct tls_tcb *tcb;
if (curthread != NULL) {
if (GC_NEEDED())
_thr_gc(curthread);
if (free_thread_count > 0) {
THR_LOCK_ACQUIRE(curthread, &free_thread_lock);
if ((thread = TAILQ_FIRST(&free_threadq)) != NULL) {
TAILQ_REMOVE(&free_threadq, thread, tle);
free_thread_count--;
}
THR_LOCK_RELEASE(curthread, &free_thread_lock);
}
}
if (thread == NULL) {
thread = malloc(sizeof(struct pthread));
if (thread == NULL)
return (NULL);
}
if (curthread != NULL) {
THR_LOCK_ACQUIRE(curthread, &tcb_lock);
tcb = _tcb_ctor(thread, 0 /* not initial tls */);
THR_LOCK_RELEASE(curthread, &tcb_lock);
} else {
tcb = _tcb_ctor(thread, 1 /* initial tls */);
}
if (tcb != NULL) {
memset(thread, 0, sizeof(*thread));
thread->tcb = tcb;
} else {
thr_destroy(curthread, thread);
thread = NULL;
}
return (thread);
}
static int
init_static_private(struct pthread *thread, pthread_mutex_t *mutex)
{
int ret;
THR_LOCK_ACQUIRE(thread, &_mutex_static_lock);
if (*mutex == NULL)
ret = _pthread_mutex_init(mutex, &static_mattr);
else
ret = 0;
THR_LOCK_RELEASE(thread, &_mutex_static_lock);
return (ret);
}
static int
init_static(pthread_rwlock_t *rwlock)
{
struct pthread *thread = _get_curthread();
int ret;
THR_LOCK_ACQUIRE(thread, &_rwlock_static_lock);
if (*rwlock == NULL)
ret = _pthread_rwlock_init(rwlock, NULL);
else
ret = 0;
THR_LOCK_RELEASE(thread, &_rwlock_static_lock);
return (ret);
}
static int
init_static(struct pthread *thread, pthread_rwlock_t *rwlock)
{
int ret;
THR_LOCK_ACQUIRE(thread, &_rwlock_static_lock);
if (*rwlock == THR_RWLOCK_INITIALIZER)
ret = rwlock_init(rwlock, NULL);
else
ret = 0;
THR_LOCK_RELEASE(thread, &_rwlock_static_lock);
return (ret);
}
static int
init_static(struct pthread *thread, pthread_cond_t *cond)
{
int ret;
THR_LOCK_ACQUIRE(thread, &_cond_static_lock);
if (*cond == NULL)
ret = cond_init(cond, NULL);
else
ret = 0;
THR_LOCK_RELEASE(thread, &_cond_static_lock);
return (ret);
}
void
_thr_tsd_unload(struct dl_phdr_info *phdr_info)
{
struct pthread *curthread = _get_curthread();
void (*destructor)(void *);
int key;
THR_LOCK_ACQUIRE(curthread, &_keytable_lock);
for (key = 0; key < PTHREAD_KEYS_MAX; key++) {
if (_thread_keytable[key].allocated) {
destructor = _thread_keytable[key].destructor;
if (destructor != NULL) {
if (__elf_phdr_match_addr(phdr_info, destructor))
_thread_keytable[key].destructor = NULL;
}
}
}
THR_LOCK_RELEASE(curthread, &_keytable_lock);
}
static inline void
check_continuation(struct pthread *curthread, struct pthread_cond *cond,
pthread_mutex_t *mutex)
{
if ((curthread->interrupted != 0) &&
(curthread->continuation != NULL)) {
if (cond != NULL)
/* Unlock the condition variable structure: */
THR_LOCK_RELEASE(curthread, &cond->c_lock);
/*
* Note that even though this thread may have been
* canceled, POSIX requires that the mutex be
* reaquired prior to cancellation.
*/
if (mutex != NULL)
_mutex_cv_lock(mutex);
curthread->continuation((void *) curthread);
PANIC("continuation returned in pthread_cond_wait.\n");
}
}
int
_pthread_key_delete(pthread_key_t key)
{
struct pthread *curthread = _get_curthread();
int ret = 0;
if ((unsigned int)key < PTHREAD_KEYS_MAX) {
/* Lock the key table: */
THR_LOCK_ACQUIRE(curthread, &_keytable_lock);
if (_thread_keytable[key].allocated)
_thread_keytable[key].allocated = 0;
else
ret = EINVAL;
/* Unlock the key table: */
THR_LOCK_RELEASE(curthread, &_keytable_lock);
} else
ret = EINVAL;
return (ret);
}
int
_pthread_cond_destroy(pthread_cond_t *cond)
{
struct pthread_cond *cv;
struct pthread *curthread = _get_curthread();
int rval = 0;
if (cond == NULL || *cond == NULL)
rval = EINVAL;
else {
/* Lock the condition variable structure: */
THR_LOCK_ACQUIRE(curthread, &(*cond)->c_lock);
/*
* NULL the caller's pointer now that the condition
* variable has been destroyed:
*/
cv = *cond;
*cond = NULL;
/* Unlock the condition variable structure: */
THR_LOCK_RELEASE(curthread, &cv->c_lock);
/* Free the cond lock structure: */
_lock_destroy(&cv->c_lock);
/*
* Free the memory allocated for the condition
* variable structure:
*/
free(cv);
}
/* Return the completion status: */
return (rval);
}
int
_pthread_cond_timedwait(pthread_cond_t * cond, pthread_mutex_t * mutex,
const struct timespec * abstime)
{
struct pthread *curthread = _get_curthread();
int rval = 0;
int done = 0;
int mutex_locked = 1;
int seqno;
THR_ASSERT(curthread->locklevel == 0,
"cv_timedwait: locklevel is not zero!");
if (abstime == NULL || abstime->tv_sec < 0 || abstime->tv_nsec < 0 ||
abstime->tv_nsec >= 1000000000)
return (EINVAL);
/*
* If the condition variable is statically initialized, perform dynamic
* initialization.
*/
if (*cond == NULL && (rval = _pthread_cond_init(cond, NULL)) != 0)
return (rval);
if (!_kse_isthreaded())
_kse_setthreaded(1);
/*
* Enter a loop waiting for a condition signal or broadcast
* to wake up this thread. A loop is needed in case the waiting
* thread is interrupted by a signal to execute a signal handler.
* It is not (currently) possible to remain in the waiting queue
* while running a handler. Instead, the thread is interrupted
* and backed out of the waiting queue prior to executing the
* signal handler.
*/
/* Lock the condition variable structure: */
THR_LOCK_ACQUIRE(curthread, &(*cond)->c_lock);
seqno = (*cond)->c_seqno;
do {
/*
* If the condvar was statically allocated, properly
* initialize the tail queue.
*/
if (((*cond)->c_flags & COND_FLAGS_INITED) == 0) {
TAILQ_INIT(&(*cond)->c_queue);
(*cond)->c_flags |= COND_FLAGS_INITED;
}
/* Process according to condition variable type: */
switch ((*cond)->c_type) {
/* Fast condition variable: */
case COND_TYPE_FAST:
if ((mutex == NULL) || (((*cond)->c_mutex != NULL) &&
((*cond)->c_mutex != *mutex))) {
/* Return invalid argument error: */
rval = EINVAL;
} else {
/* Reset the timeout and interrupted flags: */
curthread->timeout = 0;
curthread->interrupted = 0;
/*
* Queue the running thread for the condition
* variable:
*/
cond_queue_enq(*cond, curthread);
/* Unlock the mutex: */
if (mutex_locked &&
((rval = _mutex_cv_unlock(mutex)) != 0)) {
/*
* Cannot unlock the mutex; remove the
* running thread from the condition
* variable queue:
*/
cond_queue_remove(*cond, curthread);
} else {
/* Remember the mutex: */
(*cond)->c_mutex = *mutex;
/*
* Don't unlock the mutex the next
* time through the loop (if the
* thread has to be requeued after
* handling a signal).
*/
mutex_locked = 0;
/*
* This thread is active and is in a
* critical region (holding the cv
* lock); we should be able to safely
* set the state.
*/
THR_SCHED_LOCK(curthread, curthread);
/* Set the wakeup time: */
curthread->wakeup_time.tv_sec =
abstime->tv_sec;
curthread->wakeup_time.tv_nsec =
abstime->tv_nsec;
THR_SET_STATE(curthread, PS_COND_WAIT);
/* Remember the CV: */
curthread->data.cond = *cond;
curthread->sigbackout = cond_wait_backout;
THR_SCHED_UNLOCK(curthread, curthread);
/* Unlock the CV structure: */
THR_LOCK_RELEASE(curthread,
&(*cond)->c_lock);
/* Schedule the next thread: */
_thr_sched_switch(curthread);
/*
* XXX - This really isn't a good check
* since there can be more than one
* thread waiting on the CV. Signals
* sent to threads waiting on mutexes
* or CVs should really be deferred
* until the threads are no longer
* waiting, but POSIX says that signals
* should be sent "as soon as possible".
*/
done = (seqno != (*cond)->c_seqno);
if (done && !THR_IN_CONDQ(curthread)) {
/*
* The thread is dequeued, so
* it is safe to clear these.
*/
curthread->data.cond = NULL;
curthread->sigbackout = NULL;
check_continuation(curthread,
NULL, mutex);
return (_mutex_cv_lock(mutex));
}
/* Relock the CV structure: */
THR_LOCK_ACQUIRE(curthread,
&(*cond)->c_lock);
/*
* Clear these after taking the lock to
* prevent a race condition where a
* signal can arrive before dequeueing
* the thread.
*/
curthread->data.cond = NULL;
curthread->sigbackout = NULL;
done = (seqno != (*cond)->c_seqno);
if (THR_IN_CONDQ(curthread)) {
cond_queue_remove(*cond,
curthread);
/* Check for no more waiters: */
if (TAILQ_EMPTY(&(*cond)->c_queue))
(*cond)->c_mutex = NULL;
}
if (curthread->timeout != 0) {
/* The wait timedout. */
rval = ETIMEDOUT;
}
}
}
break;
/* Trap invalid condition variable types: */
default:
/* Return an invalid argument error: */
rval = EINVAL;
break;
}
check_continuation(curthread, *cond,
mutex_locked ? NULL : mutex);
} while ((done == 0) && (rval == 0));
/* Unlock the condition variable structure: */
THR_LOCK_RELEASE(curthread, &(*cond)->c_lock);
if (mutex_locked == 0)
_mutex_cv_lock(mutex);
/* Return the completion status: */
return (rval);
}
int
_pthread_cond_signal(pthread_cond_t * cond)
{
struct pthread *curthread = _get_curthread();
struct pthread *pthread;
struct kse_mailbox *kmbx;
int rval = 0;
THR_ASSERT(curthread->locklevel == 0,
"cv_timedwait: locklevel is not zero!");
if (cond == NULL)
rval = EINVAL;
/*
* If the condition variable is statically initialized, perform dynamic
* initialization.
*/
else if (*cond != NULL || (rval = _pthread_cond_init(cond, NULL)) == 0) {
/* Lock the condition variable structure: */
THR_LOCK_ACQUIRE(curthread, &(*cond)->c_lock);
/* Process according to condition variable type: */
switch ((*cond)->c_type) {
/* Fast condition variable: */
case COND_TYPE_FAST:
/* Increment the sequence number: */
(*cond)->c_seqno++;
/*
* Wakeups have to be done with the CV lock held;
* otherwise there is a race condition where the
* thread can timeout, run on another KSE, and enter
* another blocking state (including blocking on a CV).
*/
if ((pthread = TAILQ_FIRST(&(*cond)->c_queue))
!= NULL) {
THR_SCHED_LOCK(curthread, pthread);
cond_queue_remove(*cond, pthread);
pthread->sigbackout = NULL;
if ((pthread->kseg == curthread->kseg) &&
(pthread->active_priority >
curthread->active_priority))
curthread->critical_yield = 1;
kmbx = _thr_setrunnable_unlocked(pthread);
THR_SCHED_UNLOCK(curthread, pthread);
if (kmbx != NULL)
kse_wakeup(kmbx);
}
/* Check for no more waiters: */
if (TAILQ_EMPTY(&(*cond)->c_queue))
(*cond)->c_mutex = NULL;
break;
/* Trap invalid condition variable types: */
default:
/* Return an invalid argument error: */
rval = EINVAL;
break;
}
/* Unlock the condition variable structure: */
THR_LOCK_RELEASE(curthread, &(*cond)->c_lock);
}
/* Return the completion status: */
return (rval);
}
int
_pthread_cond_broadcast(pthread_cond_t * cond)
{
struct pthread *curthread = _get_curthread();
struct pthread *pthread;
struct kse_mailbox *kmbx;
int rval = 0;
THR_ASSERT(curthread->locklevel == 0,
"cv_timedwait: locklevel is not zero!");
if (cond == NULL)
rval = EINVAL;
/*
* If the condition variable is statically initialized, perform dynamic
* initialization.
*/
else if (*cond != NULL || (rval = _pthread_cond_init(cond, NULL)) == 0) {
/* Lock the condition variable structure: */
THR_LOCK_ACQUIRE(curthread, &(*cond)->c_lock);
/* Process according to condition variable type: */
switch ((*cond)->c_type) {
/* Fast condition variable: */
case COND_TYPE_FAST:
/* Increment the sequence number: */
(*cond)->c_seqno++;
/*
* Enter a loop to bring all threads off the
* condition queue:
*/
while ((pthread = TAILQ_FIRST(&(*cond)->c_queue))
!= NULL) {
THR_SCHED_LOCK(curthread, pthread);
cond_queue_remove(*cond, pthread);
pthread->sigbackout = NULL;
if ((pthread->kseg == curthread->kseg) &&
(pthread->active_priority >
curthread->active_priority))
curthread->critical_yield = 1;
kmbx = _thr_setrunnable_unlocked(pthread);
THR_SCHED_UNLOCK(curthread, pthread);
if (kmbx != NULL)
kse_wakeup(kmbx);
}
/* There are no more waiting threads: */
(*cond)->c_mutex = NULL;
break;
/* Trap invalid condition variable types: */
default:
/* Return an invalid argument error: */
rval = EINVAL;
break;
}
/* Unlock the condition variable structure: */
THR_LOCK_RELEASE(curthread, &(*cond)->c_lock);
}
/* Return the completion status: */
return (rval);
}
void
_thread_cleanupspecific(void)
{
struct pthread *curthread = _get_curthread();
void (*destructor)( void *);
const void *data = NULL;
int key;
int i;
if (curthread->specific == NULL)
return;
/* Lock the key table: */
THR_LOCK_ACQUIRE(curthread, &_keytable_lock);
for (i = 0; (i < PTHREAD_DESTRUCTOR_ITERATIONS) &&
(curthread->specific_data_count > 0); i++) {
for (key = 0; (key < PTHREAD_KEYS_MAX) &&
(curthread->specific_data_count > 0); key++) {
destructor = NULL;
if (_thread_keytable[key].allocated &&
(curthread->specific[key].data != NULL)) {
if (curthread->specific[key].seqno ==
_thread_keytable[key].seqno) {
data = curthread->specific[key].data;
destructor = _thread_keytable[key].destructor;
}
curthread->specific[key].data = NULL;
curthread->specific_data_count--;
}
else if (curthread->specific[key].data != NULL) {
/*
* This can happen if the key is deleted via
* pthread_key_delete without first setting the value
* to NULL in all threads. POSIX says that the
* destructor is not invoked in this case.
*/
curthread->specific[key].data = NULL;
curthread->specific_data_count--;
}
/*
* If there is a destructor, call it
* with the key table entry unlocked:
*/
if (destructor != NULL) {
/*
* Don't hold the lock while calling the
* destructor:
*/
THR_LOCK_RELEASE(curthread, &_keytable_lock);
destructor(__DECONST(void *, data));
THR_LOCK_ACQUIRE(curthread, &_keytable_lock);
}
}
}
THR_LOCK_RELEASE(curthread, &_keytable_lock);
free(curthread->specific);
curthread->specific = NULL;
if (curthread->specific_data_count > 0)
stderr_debug("Thread %p has exited with leftover "
"thread-specific data after %d destructor iterations\n",
curthread, PTHREAD_DESTRUCTOR_ITERATIONS);
}
