void copy_from_disk_queue_to_memory_queue(auto_drainer_t::lock_t keepalive) {
try {
while (!keepalive.get_drain_signal()->is_pulsed()) {
if (disk_queue->empty()) {
if (items_in_queue != memory_queue.size()) {
// There is a push in progress, there's no good way to wait on it, so we'll start a new coroutine later
restart_copy_coro = true;
} else {
disk_queue.reset();
}
break;
}
T value;
disk_queue->pop(&value);
if (memory_queue.full()) {
guarantee(notify_when_room_in_memory_queue == NULL);
cond_t cond;
assignment_sentry_t<cond_t *> assignment_sentry(¬ify_when_room_in_memory_queue, &cond);
wait_interruptible(&cond, keepalive.get_drain_signal());
}
memory_queue.push_back(value);
available_control.set_available(true);
}
} catch (const interrupted_exc_t &) {
/* ignore */
}
}
void copy_from_disk_queue_to_memory_queue(auto_drainer_t::lock_t keepalive) {
try {
while (!keepalive.get_drain_signal()->is_pulsed()) {
if (disk_queue->empty()) {
if (items_in_queue != memory_queue.size()) {
// There is a push in progress, there's no good way to wait on
// it, so we'll start a new coroutine later
restart_copy_coro = true;
} else {
disk_queue.reset();
}
break;
}
write_message_t wm;
copying_viewer_t viewer(&wm);
disk_queue->pop(&viewer);
if (memory_queue_free_space <= 0) {
guarantee(notify_when_room_in_memory_queue == nullptr);
cond_t cond;
assignment_sentry_t<cond_t *> assignment_sentry(
¬ify_when_room_in_memory_queue, &cond);
wait_interruptible(&cond, keepalive.get_drain_signal());
}
memory_queue_free_space -= wm.size();
memory_queue.emplace_back(std::move(wm));
available_control.set_available(true);
}
} catch (const interrupted_exc_t &) {
/* ignore */
}
}
void perform_request(const request_type &request, auto_drainer_t::lock_t keepalive) {
requests_since_last_qps_sample++;
try {
registrant.perform_request(request, keepalive.get_drain_signal());
} catch (interrupted_exc_t) {
/* ignore */
}
in_use_tickets--;
parent->return_tickets(1);
}
void on_create(registration_id_t rid, peer_id_t peer, business_card_t business_card, auto_drainer_t::lock_t keepalive) {
/* Grab the mutex to avoid race conditions if a message arrives at the
update mailbox or the delete mailbox while we're working. We must not
block between when `on_create()` begins and when `mutex_acq` is
constructed. */
mutex_t::acq_t mutex_acq(&mutex);
/* If the registrant has already deregistered but the deregistration
message arrived ahead of the registration message, it will have left a
NULL in the `registrations` map. */
typename std::map<registration_id_t, cond_t *>::iterator it = registrations.find(rid);
if (it != registrations.end()) {
guarantee(it->second == NULL);
registrations.erase(it);
return;
}
/* Construct a `registrant_t` to tell the controller that something has
now registered. */
registrant_type registrant(controller, business_card);
/* `registration` is the interface that we expose to the `on_update()`
and `on_delete()` handlers. */
cond_t deletion_cond;
/* Expose `deletion_cond` so that `on_delete()` can find it. */
map_insertion_sentry_t<registration_id_t, cond_t *> registration_map_sentry(
®istrations, rid, &deletion_cond);
/* Begin monitoring the peer so we can disconnect when necessary. */
disconnect_watcher_t peer_monitor(mailbox_manager->get_connectivity_service(), peer);
/* Release the mutex, since we're done with our initial setup phase */
{
mutex_t::acq_t doomed;
swap(mutex_acq, doomed);
}
/* Wait till it's time to shut down */
wait_any_t waiter(&deletion_cond, &peer_monitor, keepalive.get_drain_signal());
waiter.wait_lazily_unordered();
/* Reacquire the mutex, to avoid race conditions when we're
deregistering from `deleters`. I'm not sure if there re any such race
conditions, but better safe than sorry. */
{
mutex_t::acq_t reacquisition(&mutex);
swap(mutex_acq, reacquisition);
}
/* `registration_map_sentry` destructor run here; `deletion_cond` cannot
be pulsed after this. */
/* `deletion_cond` destructor run here. */
/* `registrant` destructor run here; this will tell the controller that
the registration is dead and gone. */
/* `mutex_acq` destructor run here; it's safe to release the mutex
because we're no longer touching `updaters` or `deleters`. */
}