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);
}
}
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();
}
}
}
//! Dequeues log record from the queue, blocks if no log records are ready to be processed
bool dequeue_ready(record_view& rec)
{
unique_lock< mutex_type > lock(m_mutex);
while (!m_interruption_requested)
{
if (!m_queue.empty())
{
const boost::log::aux::timestamp now = boost::log::aux::get_timestamp();
enqueued_record const& elem = m_queue.top();
const uint64_t difference = (now - elem.m_timestamp).milliseconds();
if (difference >= m_ordering_window)
{
// We got a new element
rec = elem.m_record;
m_queue.pop();
return true;
}
else
{
// Wait until the element becomes ready to be processed
m_cond.timed_wait(lock, posix_time::milliseconds(m_ordering_window - difference));
}
}
else
{
// Wait for an element to come
m_cond.wait(lock);
}
}
m_interruption_requested = false;
return false;
}
//! Enqueues a log record
void enqueue_unlocked(record_view const& rec)
{
const bool was_empty = m_queue.empty();
m_queue.push(enqueued_record(rec));
if (was_empty)
m_cond.notify_one();
}
void swap(queue_type &q) {
m_mutex.lock();
q.swap(m_queue);
if (m_queue.empty() && sleeping_on_empty) {
m_empty_conditional.signal();
}
m_mutex.unlock();
}
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;
}
/**
* 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);
}
inline bool wait_for_data() {
m_mutex.lock();
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;
}
m_mutex.unlock();
return success;
}
/// Returns immediately of queue size is >= immedeiate_size
/// Otherwise, it will poll over 'ns' nanoseconds or on a signal
/// until queue is not empty.
inline bool try_timed_wait_for_data(size_t ns, size_t immediate_size) {
m_mutex.lock();
bool success = false;
// Wait while the queue is empty and this queue is alive
if (m_queue.size() < immediate_size) {
if (m_queue.empty() && m_alive) {
sleeping++;
m_conditional.timedwait_ns(m_mutex, ns);
sleeping--;
}
}
// An element has been added or a signal was raised
if(!m_queue.empty()) {
success = true;
}
m_mutex.unlock();
return success;
}
/**
* 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);
}
//! 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.
}
//! Attempts to dequeue log record from the queue, does not block.
bool try_dequeue(record_view& rec)
{
lock_guard< mutex_type > lock(m_mutex);
if (!m_queue.empty())
{
enqueued_record const& elem = m_queue.top();
rec = elem.m_record;
m_queue.pop();
return true;
}
return false;
}
/**
* The conceptual "reverse" of dequeue().
* This function will block until the queue becomes empty, or
* until stop_blocking() is called.
* Returns true on success.
* Returns false if the queue is no longer alive
*/
bool wait_until_empty() {
m_mutex.lock();
// if the queue still has elements in it while I am still alive, wait
while (m_queue.empty() == false && m_alive == true) {
sleeping_on_empty++;
m_empty_conditional.wait(m_mutex);
sleeping_on_empty--;
}
m_mutex.unlock();
// if I am alive, the queue must be empty. i.e. success
// otherwise I am dead
return m_alive;
}
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);
}
void test_pop()
{
size_t num = 10, count = 0;
fill(num);
while (!m_queue.empty())
m_queue.pop();
ASSERT_EQ(0, m_queue.size());
for (auto i : m_queue)
count++;
ASSERT_EQ(0, count);
clear();
}
//! 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;
}
void process_queue(const Handler& h, const boost::system::error_code& ec,
std::chrono::milliseconds repeat, int repeat_count) {
// Process up to m_batch_size items waiting on the queue.
// For each dequeued item call m_wait_handler
int i = 0; // Number of handler invocations
T value;
while (i < m_batch_size && m_queue.pop(value)) {
i++;
repeat_count = dec_repeat_count(repeat_count);
if (!h(value, boost::system::error_code()))
return;
}
static const auto s_timeout =
boost::system::errc::make_error_code(boost::system::errc::timed_out);
auto pthis = this->shared_from_this();
// If we reached the batch size and queue has more data
// to process - give up the time slice and reschedule the handler
if (i == m_batch_size && !m_queue.empty()) {
m_io.post([pthis, h, repeat, repeat_count]() {
(*pthis)(h, boost::asio::error::operation_aborted, repeat, repeat_count);
});
return;
} else if (!i && !h(value, s_timeout)) {
// If we haven't processed any data and the timer was canceled.
// Invoke the callback to see if we need to remove the handler.
return;
}
int n = dec_repeat_count(repeat_count);
// If requested repeated timer, schedule new timer invocation
if (repeat > std::chrono::milliseconds(0) && n > 0) {
m_timer.cancel();
m_timer.expires_from_now(repeat);
m_timer.async_wait(
[pthis, h, repeat, n]
(const boost::system::error_code& ec) {
(*pthis)(h, ec, repeat, n);
});
}
}
//! Attempts to dequeue a log record ready for processing from the queue, does not block if no log records are ready to be processed
bool try_dequeue_ready(record_view& rec)
{
lock_guard< mutex_type > lock(m_mutex);
if (!m_queue.empty())
{
const boost::log::aux::timestamp now = boost::log::aux::get_timestamp();
enqueued_record const& elem = m_queue.top();
if (static_cast< uint64_t >((now - elem.m_timestamp).milliseconds()) >= m_ordering_window)
{
// We got a new element
rec = elem.m_record;
m_queue.pop();
return true;
}
}
return false;
}
bool empty_unsafe() {
return m_queue.empty();
}
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 ();
}
}
/// Check if there is any data in the outgoing_queue to be sent over the socket
bool outgoing_not_empty() const { return !m_outgoing_queue.empty(); }
/// Check if there is any data in the incoming_queue
bool incoming_not_empty() const { return !m_incoming_queue.empty(); }
bool empty_() const
{ return queue_.empty(); }
//! Returns true if the queue is empty
inline bool empty() {
m_mutex.lock();
bool res = m_queue.empty();
m_mutex.unlock();
return res;
}
bool empty(unsigned int timeout = 5) {
boost::shared_lock<boost::shared_mutex> lock(mutex_, boost::get_system_time() + boost::posix_time::seconds(timeout));
if (!lock.owns_lock())
return false;
return queue_.empty();
}
std::size_t size(unsigned int timeout = 5) {
boost::shared_lock<boost::shared_mutex> lock(mutex_, boost::get_system_time() + boost::posix_time::seconds(timeout));
if (!lock || queue_.empty())
return 0;
return queue_.size();
}