void message_queue::push(m_task_t task)
{
- mutex.acquire();
- queue.push(task);
- cond.signal();
- mutex.release();
+ if (queue.push(task)) {
+ // list was empty, the push must be signaled
+ mutex.acquire();
+ cond.signal();
+ mutex.release();
+ }
}
bool message_queue::pop(message*& msg, m_host_t& from, double timeout)
{
- if (timeout != 0) {
- volatile double deadline =
- timeout > 0 ? MSG_get_clock() + timeout : 0.0;
+ m_task_t task;
+ if (!queue.try_pop(task)) {
+ if (timeout == 0.0)
+ return false;
+
mutex.acquire();
- while (queue.empty() && (!deadline || deadline > MSG_get_clock())) {
+ if (!queue.try_pop(task)) {
xbt_ex_t e;
XBT_DEBUG("waiting for a message to come");
TRY {
- if (deadline)
- cond.timedwait(mutex, deadline - MSG_get_clock());
+ if (timeout > 0)
+ cond.timedwait(mutex, timeout);
else
cond.wait(mutex);
}
+ TRY_CLEANUP {
+ mutex.release();
+ }
CATCH (e) {
if (e.category != timeout_error)
RETHROW;
xbt_ex_free(e);
+ return false; // got a timeout
}
+ bool pop_was_successful = queue.try_pop(task);
+ xbt_assert(pop_was_successful);
+ } else {
+ mutex.release();
}
- mutex.release();
}
-
- if (queue.empty())
- return false;
-
- m_task_t task = queue.front();
- queue.pop();
msg = static_cast<message*>(MSG_task_get_data(task));
from = MSG_task_get_source(task);
MSG_task_destroy(task);