int
rtems_aio_enqueue (rtems_aio_request *req)
{
rtems_aio_request_chain *r_chain;
rtems_chain_control *chain;
pthread_t thid;
int result, policy;
struct sched_param param;
/* The queue should be initialized */
AIO_assert (aio_request_queue.initialized == AIO_QUEUE_INITIALIZED);
result = pthread_mutex_lock (&aio_request_queue.mutex);
if (result != 0) {
free (req);
return result;
}
/* _POSIX_PRIORITIZED_IO and _POSIX_PRIORITY_SCHEDULING are defined,
we can use aio_reqprio to lower the priority of the request */
pthread_getschedparam (pthread_self(), &policy, ¶m);
req->caller_thread = pthread_self ();
req->priority = param.sched_priority - req->aiocbp->aio_reqprio;
req->policy = policy;
req->aiocbp->error_code = EINPROGRESS;
req->aiocbp->return_value = 0;
if ((aio_request_queue.idle_threads == 0) &&
aio_request_queue.active_threads < AIO_MAX_THREADS)
/* we still have empty places on the active_threads chain */
{
chain = &aio_request_queue.work_req;
r_chain = rtems_aio_search_fd (chain, req->aiocbp->aio_fildes, 1);
if (r_chain->new_fd == 1) {
rtems_chain_prepend (&r_chain->perfd, &req->next_prio);
r_chain->new_fd = 0;
pthread_mutex_init (&r_chain->mutex, NULL);
pthread_cond_init (&r_chain->cond, NULL);
AIO_printf ("New thread \n");
result = pthread_create (&thid, &aio_request_queue.attr,
rtems_aio_handle, (void *) r_chain);
if (result != 0) {
pthread_mutex_unlock (&aio_request_queue.mutex);
return result;
}
++aio_request_queue.active_threads;
}
else {
/* put request in the fd chain it belongs to */
pthread_mutex_lock (&r_chain->mutex);
rtems_aio_insert_prio (&r_chain->perfd, req);
pthread_cond_signal (&r_chain->cond);
pthread_mutex_unlock (&r_chain->mutex);
}
}
else
{
/* the maximum number of threads has been already created
even though some of them might be idle.
The request belongs to one of the active fd chain */
r_chain = rtems_aio_search_fd (&aio_request_queue.work_req,
req->aiocbp->aio_fildes, 0);
if (r_chain != NULL)
{
pthread_mutex_lock (&r_chain->mutex);
rtems_aio_insert_prio (&r_chain->perfd, req);
pthread_cond_signal (&r_chain->cond);
pthread_mutex_unlock (&r_chain->mutex);
} else {
/* or to the idle chain */
chain = &aio_request_queue.idle_req;
r_chain = rtems_aio_search_fd (chain, req->aiocbp->aio_fildes, 1);
if (r_chain->new_fd == 1) {
/* If this is a new fd chain we signal the idle threads that
might be waiting for requests */
AIO_printf (" New chain on waiting queue \n ");
rtems_chain_prepend (&r_chain->perfd, &req->next_prio);
r_chain->new_fd = 0;
pthread_mutex_init (&r_chain->mutex, NULL);
pthread_cond_init (&r_chain->cond, NULL);
} else
/* just insert the request in the existing fd chain */
rtems_aio_insert_prio (&r_chain->perfd, req);
if (aio_request_queue.idle_threads > 0)
pthread_cond_signal (&aio_request_queue.new_req);
}
}
pthread_mutex_unlock (&aio_request_queue.mutex);
return 0;
}
int aio_cancel(int fildes, struct aiocb *aiocbp)
{
rtems_chain_control *idle_req_chain = &aio_request_queue.idle_req;
rtems_chain_control *work_req_chain = &aio_request_queue.work_req;
rtems_aio_request_chain *r_chain;
int result;
pthread_mutex_lock (&aio_request_queue.mutex);
if (fcntl (fildes, F_GETFD) < 0) {
pthread_mutex_unlock(&aio_request_queue.mutex);
rtems_set_errno_and_return_minus_one (EBADF);
}
/* if aiocbp is NULL remove all request for given file descriptor */
if (aiocbp == NULL) {
AIO_printf ("Cancel all requests\n");
r_chain = rtems_aio_search_fd (work_req_chain, fildes, 0);
if (r_chain == NULL) {
AIO_printf ("Request chain not on [WQ]\n");
if (!rtems_chain_is_empty (idle_req_chain)) {
r_chain = rtems_aio_search_fd (idle_req_chain, fildes, 0);
if (r_chain == NULL) {
pthread_mutex_unlock(&aio_request_queue.mutex);
return AIO_ALLDONE;
}
AIO_printf ("Request chain on [IQ]\n");
rtems_chain_extract (&r_chain->next_fd);
rtems_aio_remove_fd (r_chain);
pthread_mutex_destroy (&r_chain->mutex);
pthread_cond_destroy (&r_chain->mutex);
free (r_chain);
pthread_mutex_unlock (&aio_request_queue.mutex);
return AIO_CANCELED;
}
pthread_mutex_unlock (&aio_request_queue.mutex);
return AIO_ALLDONE;
}
AIO_printf ("Request chain on [WQ]\n");
pthread_mutex_lock (&r_chain->mutex);
rtems_chain_extract (&r_chain->next_fd);
rtems_aio_remove_fd (r_chain);
pthread_mutex_unlock (&r_chain->mutex);
pthread_mutex_unlock (&aio_request_queue.mutex);
return AIO_CANCELED;
} else {
AIO_printf ("Cancel request\n");
if (aiocbp->aio_fildes != fildes) {
pthread_mutex_unlock (&aio_request_queue.mutex);
rtems_set_errno_and_return_minus_one (EINVAL);
}
r_chain = rtems_aio_search_fd (work_req_chain, fildes, 0);
if (r_chain == NULL) {
if (!rtems_chain_is_empty (idle_req_chain)) {
r_chain = rtems_aio_search_fd (idle_req_chain, fildes, 0);
if (r_chain == NULL) {
pthread_mutex_unlock (&aio_request_queue.mutex);
rtems_set_errno_and_return_minus_one (EINVAL);
}
AIO_printf ("Request on [IQ]\n");
result = rtems_aio_remove_req (&r_chain->perfd, aiocbp);
pthread_mutex_unlock (&aio_request_queue.mutex);
return result;
} else {
pthread_mutex_unlock (&aio_request_queue.mutex);
return AIO_ALLDONE;
}
}
AIO_printf ("Request on [WQ]\n");
pthread_mutex_lock (&r_chain->mutex);
result = rtems_aio_remove_req (&r_chain->perfd, aiocbp);
pthread_mutex_unlock (&r_chain->mutex);
pthread_mutex_unlock (&aio_request_queue.mutex);
return result;
}
return AIO_ALLDONE;
}