/**
* Starts the main scheduler loop which performs task scheduling for this
* domain.
*
* Returns once no more tasks can be scheduled and all task ref_counts
* drop to zero.
*/
void
rust_scheduler::start_main_loop() {
lock.lock();
// Make sure someone is watching, to pull us out of infinite loops.
//
// FIXME: time-based interruption is not presently working; worked
// in rustboot and has been completely broken in rustc.
//
// rust_timer timer(this);
DLOG(this, dom, "started domain loop %d", id);
while (kernel->live_tasks > 0) {
A(this, kernel->is_deadlocked() == false, "deadlock");
DLOG(this, dom, "worker %d, number_of_live_tasks = %d, total = %d",
id, number_of_live_tasks(), kernel->live_tasks);
rust_task *scheduled_task = schedule_task(id);
if (scheduled_task == NULL) {
log_state();
DLOG(this, task,
"all tasks are blocked, scheduler id %d yielding ...",
id);
lock.timed_wait(10);
reap_dead_tasks(id);
DLOG(this, task,
"scheduler %d resuming ...", id);
continue;
}
I(this, scheduled_task->running());
DLOG(this, task,
"activating task %s 0x%" PRIxPTR
", sp=0x%" PRIxPTR
", state: %s",
scheduled_task->name,
(uintptr_t)scheduled_task,
scheduled_task->user.rust_sp,
scheduled_task->state->name);
place_task_in_tls(scheduled_task);
interrupt_flag = 0;
DLOG(this, task,
"Running task %p on worker %d",
scheduled_task, id);
scheduled_task->running_on = id;
activate(scheduled_task);
scheduled_task->running_on = -1;
DLOG(this, task,
"returned from task %s @0x%" PRIxPTR
" in state '%s', sp=0x%x, worker id=%d" PRIxPTR,
scheduled_task->name,
(uintptr_t)scheduled_task,
scheduled_task->state->name,
scheduled_task->user.rust_sp,
id);
reap_dead_tasks(id);
}
DLOG(this, dom,
"terminated scheduler loop, reaping dead tasks ...");
while (dead_tasks.length() > 0) {
DLOG(this, dom,
"waiting for %d dead tasks to become dereferenced, "
"scheduler yielding ...",
dead_tasks.length());
log_state();
lock.unlock();
sync::yield();
lock.lock();
reap_dead_tasks(id);
}
DLOG(this, dom, "finished main-loop %d", id);
lock.unlock();
}
rust_sched_loop_state
rust_sched_loop::run_single_turn() {
DLOG(this, task,
"scheduler %d resuming ...", id);
lock.lock();
if (!should_exit) {
assert(dead_task == NULL && "Tasks should only die after running");
DLOG(this, dom, "worker %d, number_of_live_tasks = %d",
id, number_of_live_tasks());
rust_task *scheduled_task = schedule_task();
if (scheduled_task == NULL) {
log_state();
DLOG(this, task,
"all tasks are blocked, scheduler id %d yielding ...",
id);
lock.unlock();
return sched_loop_state_block;
}
scheduled_task->assert_is_running();
DLOG(this, task,
"activating task %s 0x%" PRIxPTR
", state: %s",
scheduled_task->name,
(uintptr_t)scheduled_task,
state_name(scheduled_task->get_state()));
place_task_in_tls(scheduled_task);
DLOG(this, task,
"Running task %p on worker %d",
scheduled_task, id);
activate(scheduled_task);
DLOG(this, task,
"returned from task %s @0x%" PRIxPTR
" in state '%s', worker id=%d" PRIxPTR,
scheduled_task->name,
(uintptr_t)scheduled_task,
state_name(scheduled_task->get_state()),
id);
reap_dead_tasks();
lock.unlock();
return sched_loop_state_keep_going;
} else {
assert(running_tasks.is_empty() && "Should have no running tasks");
assert(blocked_tasks.is_empty() && "Should have no blocked tasks");
assert(dead_task == NULL && "Should have no dead tasks");
DLOG(this, dom, "finished main-loop %d", id);
lock.unlock();
assert(!extra_c_stack);
if (cached_c_stack) {
destroy_exchange_stack(kernel->region(), cached_c_stack);
cached_c_stack = NULL;
}
assert(!extra_big_stack);
if (cached_big_stack) {
destroy_exchange_stack(kernel->region(), cached_big_stack);
cached_big_stack = NULL;
}
sched->release_task_thread();
return sched_loop_state_exit;
}
}
/**
* Starts the main scheduler loop which performs task scheduling for this
* domain.
*
* Returns once no more tasks can be scheduled and all task ref_counts
* drop to zero.
*/
void
rust_task_thread::start_main_loop() {
lock.lock();
DLOG(this, dom, "started domain loop %d", id);
while (!should_exit) {
DLOG(this, dom, "worker %d, number_of_live_tasks = %d",
id, number_of_live_tasks());
rust_task *scheduled_task = schedule_task();
if (scheduled_task == NULL) {
log_state();
DLOG(this, task,
"all tasks are blocked, scheduler id %d yielding ...",
id);
lock.wait();
reap_dead_tasks();
DLOG(this, task,
"scheduler %d resuming ...", id);
continue;
}
I(this, scheduled_task->running());
DLOG(this, task,
"activating task %s 0x%" PRIxPTR
", sp=0x%" PRIxPTR
", state: %s",
scheduled_task->name,
(uintptr_t)scheduled_task,
scheduled_task->user.rust_sp,
scheduled_task->state->name);
place_task_in_tls(scheduled_task);
DLOG(this, task,
"Running task %p on worker %d",
scheduled_task, id);
activate(scheduled_task);
DLOG(this, task,
"returned from task %s @0x%" PRIxPTR
" in state '%s', sp=0x%x, worker id=%d" PRIxPTR,
scheduled_task->name,
(uintptr_t)scheduled_task,
scheduled_task->state->name,
scheduled_task->user.rust_sp,
id);
reap_dead_tasks();
}
A(this, newborn_tasks.is_empty(), "Should have no newborn tasks");
A(this, running_tasks.is_empty(), "Should have no running tasks");
A(this, blocked_tasks.is_empty(), "Should have no blocked tasks");
A(this, dead_tasks.is_empty(), "Should have no dead tasks");
DLOG(this, dom, "finished main-loop %d", id);
lock.unlock();
}
