diff options
Diffstat (limited to 'lib/libkse/thread/thr_cond.c')
| -rw-r--r-- | lib/libkse/thread/thr_cond.c | 102 |
1 files changed, 72 insertions, 30 deletions
diff --git a/lib/libkse/thread/thr_cond.c b/lib/libkse/thread/thr_cond.c index 2eb05f9..09c5f22 100644 --- a/lib/libkse/thread/thr_cond.c +++ b/lib/libkse/thread/thr_cond.c @@ -157,8 +157,7 @@ pthread_cond_destroy(pthread_cond_t * cond) int pthread_cond_wait(pthread_cond_t * cond, pthread_mutex_t * mutex) { - int rval = 0; - int status; + int rval = 0; if (cond == NULL) rval = EINVAL; @@ -169,6 +168,9 @@ pthread_cond_wait(pthread_cond_t * cond, pthread_mutex_t * mutex) */ else if (*cond != NULL || (rval = pthread_cond_init(cond,NULL)) == 0) { + + _thread_enter_cancellation_point(); + /* Lock the condition variable structure: */ _SPINLOCK(&(*cond)->lock); @@ -193,8 +195,9 @@ pthread_cond_wait(pthread_cond_t * cond, pthread_mutex_t * mutex) /* Return invalid argument error: */ rval = EINVAL; } else { - /* Reset the timeout flag: */ + /* Reset the timeout and interrupted flags: */ _thread_run->timeout = 0; + _thread_run->interrupted = 0; /* * Queue the running thread for the condition @@ -233,7 +236,28 @@ pthread_cond_wait(pthread_cond_t * cond, pthread_mutex_t * mutex) _thread_kern_sched_state_unlock(PS_COND_WAIT, &(*cond)->lock, __FILE__, __LINE__); - /* Lock the mutex: */ + if (_thread_run->interrupted != 0) { + /* + * Lock the condition variable + * while removing the thread. + */ + _SPINLOCK(&(*cond)->lock); + + cond_queue_remove(*cond, + _thread_run); + + /* Check for no more waiters: */ + if (TAILQ_FIRST(&(*cond)->c_queue) == NULL) + (*cond)->c_mutex = NULL; + + _SPINUNLOCK(&(*cond)->lock); + } + + /* + * Note that even though this thread may have + * been canceled, POSIX requires that the mutex + * be reaquired prior to cancellation. + */ rval = _mutex_cv_lock(mutex); } } @@ -248,6 +272,13 @@ pthread_cond_wait(pthread_cond_t * cond, pthread_mutex_t * mutex) rval = EINVAL; break; } + + if ((_thread_run->cancelflags & PTHREAD_CANCEL_NEEDED) != 0) { + _thread_exit_cleanup(); + pthread_exit(PTHREAD_CANCELED); + } + + _thread_leave_cancellation_point(); } /* Return the completion status: */ @@ -258,8 +289,7 @@ int pthread_cond_timedwait(pthread_cond_t * cond, pthread_mutex_t * mutex, const struct timespec * abstime) { - int rval = 0; - int status; + int rval = 0; if (cond == NULL || abstime == NULL) rval = EINVAL; @@ -276,6 +306,9 @@ pthread_cond_timedwait(pthread_cond_t * cond, pthread_mutex_t * mutex, */ if (*cond != NULL || (rval = pthread_cond_init(cond,NULL)) == 0) { + + _thread_enter_cancellation_point(); + /* Lock the condition variable structure: */ _SPINLOCK(&(*cond)->lock); @@ -306,8 +339,9 @@ pthread_cond_timedwait(pthread_cond_t * cond, pthread_mutex_t * mutex, _thread_run->wakeup_time.tv_nsec = abstime->tv_nsec; - /* Reset the timeout flag: */ + /* Reset the timeout and interrupted flags: */ _thread_run->timeout = 0; + _thread_run->interrupted = 0; /* * Queue the running thread for the condition @@ -341,12 +375,16 @@ pthread_cond_timedwait(pthread_cond_t * cond, pthread_mutex_t * mutex, _thread_kern_sched_state_unlock(PS_COND_WAIT, &(*cond)->lock, __FILE__, __LINE__); - /* Check if the wait timedout: */ - if (_thread_run->timeout == 0) { + /* + * Check if the wait timedout or was + * interrupted (canceled): + */ + if ((_thread_run->timeout == 0) && + (_thread_run->interrupted == 0)) { /* Lock the mutex: */ rval = _mutex_cv_lock(mutex); - } - else { + + } else { /* Lock the condition variable structure: */ _SPINLOCK(&(*cond)->lock); @@ -369,8 +407,12 @@ pthread_cond_timedwait(pthread_cond_t * cond, pthread_mutex_t * mutex, rval = ETIMEDOUT; /* - * Lock the mutex and ignore - * any errors: + * Lock the mutex and ignore any + * errors. Note that even though + * this thread may have been + * canceled, POSIX requires that + * the mutex be reaquired prior + * to cancellation. */ (void)_mutex_cv_lock(mutex); } @@ -388,6 +430,12 @@ pthread_cond_timedwait(pthread_cond_t * cond, pthread_mutex_t * mutex, break; } + if ((_thread_run->cancelflags & PTHREAD_CANCEL_NEEDED) != 0) { + _thread_exit_cleanup(); + pthread_exit(PTHREAD_CANCELED); + } + + _thread_leave_cancellation_point(); } /* Return the completion status: */ @@ -416,16 +464,7 @@ pthread_cond_signal(pthread_cond_t * cond) switch ((*cond)->c_type) { /* Fast condition variable: */ case COND_TYPE_FAST: - /* - * Enter a loop to dequeue threads from the condition - * queue until we find one that hasn't previously - * timed out. - */ - while (((pthread = cond_queue_deq(*cond)) != NULL) && - (pthread->timeout != 0)) { - } - - if (pthread != NULL) + if ((pthread = cond_queue_deq(*cond)) != NULL) /* Allow the thread to run: */ PTHREAD_NEW_STATE(pthread,PS_RUNNING); @@ -482,12 +521,7 @@ pthread_cond_broadcast(pthread_cond_t * cond) * condition queue: */ while ((pthread = cond_queue_deq(*cond)) != NULL) { - /* - * The thread is already running if the - * timeout flag is set. - */ - if (pthread->timeout == 0) - PTHREAD_NEW_STATE(pthread,PS_RUNNING); + PTHREAD_NEW_STATE(pthread,PS_RUNNING); } /* There are no more waiting threads: */ @@ -524,9 +558,17 @@ cond_queue_deq(pthread_cond_t cond) { pthread_t pthread; - if ((pthread = TAILQ_FIRST(&cond->c_queue)) != NULL) { + while ((pthread = TAILQ_FIRST(&cond->c_queue)) != NULL) { TAILQ_REMOVE(&cond->c_queue, pthread, qe); pthread->flags &= ~PTHREAD_FLAGS_IN_CONDQ; + if ((pthread->timeout == 0) && (pthread->interrupted == 0)) + /* + * Only exit the loop when we find a thread + * that hasn't timed out or been canceled; + * those threads are already running and don't + * need their run state changed. + */ + break; } return(pthread); |
