/* Switch to the next task in the run queue. */
static void
mm_task_switch(mm_task_state_t state)
{
// Move the currently running task to a new state.
struct mm_task *old_task = mm_core->task;
ASSERT(old_task->state == MM_TASK_RUNNING);
old_task->state = state;
if (unlikely(state == MM_TASK_INVALID)) {
// Add it to the dead task list.
mm_list_append(&mm_core->dead, &old_task->queue);
} else {
// Reset the priority that could have been temporary raised.
old_task->priority = old_task->original_priority;
if (state == MM_TASK_PENDING) {
// Add it to the run queue.
mm_runq_put(&mm_core->runq, old_task);
}
}
// Get the next task from the run queue. As long as this function
// is called there is at least a boot task in the run queue. So
// there should never be a NULL value returned.
struct mm_task *new_task = mm_runq_get(&mm_core->runq);
new_task->state = MM_TASK_RUNNING;
mm_core->task = new_task;
// Switch to the new task relinquishing CPU control for a while.
mm_stack_switch(&old_task->stack_ctx, &new_task->stack_ctx);
// Resume the task unless it has been canceled and it agrees to be
// canceled asynchronously. In that case it quits here.
mm_task_testcancel_asynchronous();
}
static void
mm_timeq_insert_t1(struct mm_timeq *timeq, struct mm_timeq_entry *entry)
{
int index = timeq->t1_index + (entry->value - timeq->t1_start) / timeq->t1_width;
ASSERT(index < timeq->t1_count);
mm_list_append(&timeq->t1[index], &entry->queue);
entry->index = index;
DEBUG("entry: %p, t1 index: %d", entry, index);
}
mm_port_create(struct mm_task *task)
{
ENTER();
struct mm_port *port = mm_global_alloc(sizeof(struct mm_port));
port->lock = (mm_regular_lock_t) MM_REGULAR_LOCK_INIT;
port->task = task;
port->start = 0;
port->count = 0;
mm_waitset_prepare(&port->blocked_senders);
mm_list_append(&task->ports, &port->ports);
LEAVE();
return port;
}
static void
mm_timeq_insert_t2(struct mm_timeq *timeq, struct mm_timeq_entry *entry)
{
mm_list_append(&timeq->t2, &entry->queue);
entry->index = MM_TIMEQ_INDEX_T2;
timeq->t2_num++;
if (timeq->t2_min > entry->value) {
timeq->t2_min = entry->value;
}
if (timeq->t2_max < entry->value) {
timeq->t2_max = entry->value;
}
DEBUG("entry: %p, t2 num: %d", entry, timeq->t2_num);
}
void *
mm_task_alloc(size_t size)
{
ENTER();
ASSERT(size > 0);
/* Allocate the requested memory plus some extra for the list link. */
void *ptr = mm_local_alloc(size + sizeof(struct mm_list));
/* Keep the allocated memory in the task's chunk list. */
struct mm_task *task = mm_task_self();
mm_list_append(&task->chunks, (struct mm_list *) ptr);
/* Get the address past the list link. */
ptr = (void *) (((char *) ptr) + sizeof(struct mm_list));
LEAVE();
return ptr;
}
mm_task_combiner_execute(struct mm_task_combiner *combiner,
mm_combiner_routine_t routine, uintptr_t data)
{
ENTER();
// Disable cancellation as the enqueue algorithm cannot be
// safely undone if interrupted in the middle.
int cancelstate;
mm_task_setcancelstate(MM_TASK_CANCEL_DISABLE, &cancelstate);
// Get per-core queue of pending requests.
mm_core_t core = mm_core_self();
struct mm_list *wait_queue = MM_THREAD_LOCAL_DEREF(core, combiner->wait_queue);
// Add the current request to the per-core queue.
struct mm_task *task = mm_task_selfptr();
task->flags |= MM_TASK_COMBINING;
mm_list_append(wait_queue, &task->wait_queue);
// Wait until the current request becomes the head of the
// per-core queue.
while (mm_list_head(wait_queue) != &task->wait_queue)
mm_task_block();
mm_combiner_execute(&combiner->combiner, routine, data);
// Remove the request from the per-core queue.
mm_list_delete(&task->wait_queue);
task->flags &= ~MM_TASK_COMBINING;
// If the per-core queue is not empty then let its new head take
// the next turn.
if (!mm_list_empty(wait_queue)) {
struct mm_link *link = mm_list_head(wait_queue);
task = containerof(link, struct mm_task, wait_queue);
mm_task_run(task);
}
// Restore cancellation.
mm_task_setcancelstate(cancelstate, NULL);
LEAVE();
}
