/// <summary>
/// Invokes the pulse operation.
/// </summary>
private void Pulse(PulseOperation pulseOperation)
{
if (pulseOperation is PulseOperation.Next)
{
if (this.WaitQueue.Count > 0)
{
// System.Threading.Monitor has FIFO semantics.
var waitingOp = this.WaitQueue[0];
this.WaitQueue.RemoveAt(0);
this.ReadyQueue.Add(waitingOp);
IO.Debug.WriteLine("<Coyote> Operation '{0}' is pulsed by task '{1}'.",
waitingOp.Id, SystemTask.CurrentId);
}
}
else
{
foreach (var waitingOp in this.WaitQueue)
{
this.ReadyQueue.Add(waitingOp);
IO.Debug.WriteLine("<Coyote> Operation '{0}' is pulsed by task '{1}'.",
waitingOp.Id, SystemTask.CurrentId);
}
this.WaitQueue.Clear();
}
}
/// <summary>
/// Schedules a pulse operation that will either execute immediately or be scheduled
/// to execute after the current owner releases the lock. This nondeterministic action
/// is controlled by the runtime to simulate scenarios where the pulse is delayed by
/// the operation system.
/// </summary>
private void SchedulePulse(PulseOperation pulseOperation)
{
var op = this.Resource.Runtime.GetExecutingOperation();
if (this.Owner != op)
{
throw new SystemSynchronizationLockException();
}
// Pulse has a delay in the operating system, we can simulate that here
// by scheduling the pulse operation to be executed nondeterministically.
this.PulseQueue.Enqueue(pulseOperation);
if (this.PulseQueue.Count is 1)
{
// Create a task for draining the queue. To optimize the testing performance,
// we create and maintain a single task to perform this role.
Task.Run(this.DrainPulseQueue);
}
}
