private ValueTask WaitForCallbackIfNecessaryAsync()
{
// Same as WaitForCallbackIfNecessary, except returning a task that'll be completed when callbacks complete.
CancellationTokenSource source = _node.Partition.Source;
if (source.IsCancellationRequested && // Running callbacks has commenced.
!source.IsCancellationCompleted && // Running callbacks hasn't finished.
source.ThreadIDExecutingCallbacks != Environment.CurrentManagedThreadId) // The executing thread ID is not this thread's ID.
{
// Callback execution is in progress, the executing thread is different from this thread and has taken the callback for execution
// so get a task that'll complete when this target callback is no longer the executing callback.
return source.WaitForCallbackToCompleteAsync(_id);
}
// Callback is either already completed, won't execute, or the callback itself is calling this.
return default;
}
