void log_non_empty_queue(char const* const desc, queue_type& queue)
{
mutex_type::scoped_lock l(mtx_);
while (!queue.empty()) {
threads::thread_id_type id = queue.front().id_;
queue.front().id_ = 0;
queue.pop_front();
// we know that the id is actually the pointer to the thread
threads::thread_data* thrd = reinterpret_cast<threads::thread_data*>(id);
LERR_(info) << "~full_empty_entry: aborting pending thread in "
<< desc << ": "
<< get_thread_state_name(thrd->get_state())
<< "(" << id << "): " << thrd->get_description();
// forcefully abort thread, do not throw
error_code ec(lightweight);
threads::set_thread_state(id, threads::pending,
threads::wait_abort, threads::thread_priority_normal, ec);
if (ec) {
LERR_(error) << "~full_empty_entry: could not abort thread"
<< get_thread_state_name(thrd->get_state())
<< "(" << id << "): " << thrd->get_description();
}
}
}
boost::optional<T> pop(unsigned int timeout = 5) {
boost::unique_lock<boost::shared_mutex> lock(mutex_, boost::get_system_time() + boost::posix_time::seconds(timeout));
if (!lock || queue_.empty())
return boost::optional<T>();
boost::optional<T> ret = queue_.front();
queue_.pop();
return ret;
}
//! Equality operator.
bool operator==(const iterator& it)const {
if (m_queue.size() != it.m_queue.size()) { // if the queue size is different
return false; // the state of the to iterator are different
}
if (m_queue.empty()) { // if the queue is empty, we have to check if they are valid and
return it.m_valid == m_valid and it.m_cst == m_cst; // belong to the same cst
}
return (it.m_valid == m_valid) // valid status is equal => for end() iterator
and (it.m_cst == m_cst) // iterator belongs to the same cst
and (it.m_queue.front() == m_queue.front()) // front element and
and (it.m_queue.back() == m_queue.back()); // back element are the same.
}
inline std::pair<T, bool> try_dequeue_in_critical_section() {
T elem = T();
// Wait while the queue is empty and this queue is alive
if (m_queue.empty() || m_alive == false) {
return std::make_pair(elem, false);
}
else {
elem = m_queue.front();
m_queue.pop_front();
if (m_queue.empty() && sleeping_on_empty) {
m_empty_conditional.signal();
}
return std::make_pair(elem, true);
}
}
//! Attempts to dequeue log record from the queue, does not block if the queue is empty
bool try_dequeue(record_view& rec)
{
lock_guard< mutex_type > lock(m_mutex);
const std::size_t size = m_queue.size();
if (size > 0)
{
rec.swap(m_queue.front());
m_queue.pop();
if (size == MaxQueueSizeV)
overflow_strategy::on_queue_space_available();
return true;
}
return false;
}
//! Prefix increment of the iterator.
iterator& operator++()
{
if (!m_valid) return *this;
if (m_queue.empty()) {
m_valid = false;
return *this;
}
value_type v = m_queue.front();
m_queue.pop();
value_type child = m_cst->select_child(v, 1);
while (m_cst->root() != child) {
m_queue.push(child);
child = m_cst->sibling(child);
}
return *this;
}
/**
* Returns an element if the queue has an entry.
* returns [item, false] otherwise.
*/
inline std::pair<T, bool> try_dequeue() {
if (m_queue.empty() || m_alive == false) return std::make_pair(T(), false);
m_mutex.lock();
T elem = T();
// Wait while the queue is empty and this queue is alive
if (m_queue.empty() || m_alive == false) {
m_mutex.unlock();
return std::make_pair(elem, false);
}
else {
elem = m_queue.front();
m_queue.pop_front();
}
m_mutex.unlock();
return std::make_pair(elem, true);
}
/**
* Blocks until an element is available in the queue
* or until stop_blocking() is called.
* The return value is a pair of <T value, bool success>
* If "success" if set, then "value" is valid and
* is an element popped from the queue.
* If "success" is false, stop_blocking() was called
* and the queue has been destroyed.
*/
inline std::pair<T, bool> dequeue() {
m_mutex.lock();
T elem = T();
bool success = false;
// Wait while the queue is empty and this queue is alive
while(m_queue.empty() && m_alive) {
sleeping++;
fiber_sleep();
sleeping--;
}
// An element has been added or a signal was raised
if(!m_queue.empty()) {
success = true;
elem = m_queue.front();
m_queue.pop_front();
}
m_mutex.unlock();
return std::make_pair(elem, success);
}
inline std::pair<T, bool> dequeue_and_begin_critical_section_on_success() {
m_mutex.lock();
T elem = T();
bool success = false;
// Wait while the queue is empty and this queue is alive
while(m_queue.empty() && m_alive) {
sleeping++;
m_conditional.wait(m_mutex);
sleeping--;
}
// An element has been added or a signal was raised
if(!m_queue.empty()) {
success = true;
elem = m_queue.front();
m_queue.pop_front();
if (m_queue.empty() && sleeping_on_empty) {
m_empty_conditional.signal();
}
}
if (!success) m_mutex.unlock();
return std::make_pair(elem, success);
}
//! Dequeues log record from the queue, blocks if the queue is empty
bool dequeue_ready(record_view& rec)
{
unique_lock< mutex_type > lock(m_mutex);
while (!m_interruption_requested)
{
const std::size_t size = m_queue.size();
if (size > 0)
{
rec.swap(m_queue.front());
m_queue.pop();
if (size == MaxQueueSizeV)
overflow_strategy::on_queue_space_available();
return true;
}
else
{
m_cond.wait(lock);
}
}
m_interruption_requested = false;
return false;
}
//! Method for dereferencing the iterator.
const_reference operator*() const { return m_queue.front(); }
void dequeue_( msg_type & msg)
{
msg = queue_.front();
queue_.pop();
}
static inline void
finish (bool output_fired,
bd_t bda,
bd_t bdb)
{
if (action_.automaton.get () != 0) {
// We were executing an action of this automaton.
switch (action_.action->type) {
case INPUT:
// We were executing an input. Move to the next input.
++input_action_pos_;
proceed_to_input ();
// -EEE
input_action_list_.front ()->output_action.automaton->unlock_execution ();
finish_output ();
break;
case OUTPUT:
// We were executing an output ...
if (output_fired) {
// ... and the output output did something.
output_buffer_a_ = action_.automaton->lookup_buffer (bda);
// Synchronize the buffers.
if (output_buffer_a_.get () != 0) {
output_buffer_a_->sync (0, output_buffer_a_->size ());
}
output_buffer_b_ = action_.automaton->lookup_buffer (bdb);
if (output_buffer_b_.get () != 0) {
output_buffer_b_->sync (0, output_buffer_b_->size ());
}
// Proceed to execute the inputs.
input_action_pos_ = input_action_list_.begin ();
// This does not return if there are inputs.
proceed_to_input ();
}
// No input actions to execute.
// -EEE
action_.automaton->unlock_execution ();
finish_output ();
break;
case INTERNAL:
case SYSTEM:
// -EEE
action_.automaton->unlock_execution ();
break;
}
}
// We are done with the current action.
action_.automaton = shared_ptr<automaton> ();
for (;;) {
irq_handler::process_interrupts ();
while (!ready_queue_.empty ()) {
// Get the automaton context and remove it from the ready queue.
automaton_context* c = ready_queue_.front ();
ready_queue_.pop_front ();
// Load the action.
action_ = c->front ();
c->pop_front ();
// The automaton exists. Continue loading and execute.
switch (action_.action->type) {
case INPUT:
// Error. Not a local action.
kpanic ("Non-local action on execution queue");
break;
case OUTPUT:
{
kassert (input_action_list_.empty ());
// Copy the bindings.
action_.automaton->copy_bound_inputs (action_, back_inserter (input_action_list_));
// Sort the bindings by input automaton.
sort (input_action_list_.begin (), input_action_list_.end (), sort_bindings_by_input ());
// We lock the automata in order. This is called Havender's Principle.
bool output_locked = false;
for (input_action_list_type::const_iterator pos = input_action_list_.begin ();
pos != input_action_list_.end ();
++pos) {
shared_ptr<automaton> input_automaton = (*pos)->input_action.automaton;
if (!output_locked && action_.automaton->aid () < input_automaton->aid ()) {
// +EEE
action_.automaton->lock_execution ();
output_locked = true;
}
// +FFF
input_automaton->lock_execution ();
}
if (!output_locked) {
// +EEE
action_.automaton->lock_execution ();
output_locked = true;
}
input_action_pos_ = input_action_list_.begin ();
}
break;
case INTERNAL:
case SYSTEM:
// +EEE
action_.automaton->lock_execution ();
break;
}
if (!c->empty ()) {
// Automaton has more actions, return to ready queue.
ready_queue_.push_back (c);
}
action_.automaton->execute (*action_.action, action_.parameter, output_buffer_a_, output_buffer_b_);
}
// Out of actions.
action_.automaton = shared_ptr<automaton> ();
irq_handler::wait_for_interrupt ();
}
}