private static Action GetActionLogDelegate(int continuationId, Action action)
{
return(() =>
{
Guid activityId = TplEventSource.CreateGuidForTaskID(continuationId);
System.Diagnostics.Tracing.EventSource.SetCurrentThreadActivityId(activityId, out Guid savedActivityId);
try { action(); }
finally { System.Diagnostics.Tracing.EventSource.SetCurrentThreadActivityId(savedActivityId); }
});
}
/// <summary>Calls InvokeOrPostAction(false) on the supplied SynchronizationContextAwaitTaskContinuation.</summary>
/// <param name="state">The SynchronizationContextAwaitTaskContinuation.</param>
private static void PostAction(object state)
{
var c = (SynchronizationContextAwaitTaskContinuation)state;
TplEventSource log = TplEventSource.Log;
if (log.TasksSetActivityIds && c.m_continuationId != 0)
{
c.m_syncContext.Post(s_postCallback, GetActionLogDelegate(c.m_continuationId, c.m_action));
}
else
{
c.m_syncContext.Post(s_postCallback, c.m_action); // s_postCallback is manually cached, as the compiler won't in a SecurityCritical method
}
}
/// <summary>Inlines or schedules the continuation.</summary>
/// <param name="task">The antecedent task, which is ignored.</param>
/// <param name="canInlineContinuationTask">true if inlining is permitted; otherwise, false.</param>
internal sealed override void Run(Task task, bool canInlineContinuationTask)
{
// If we're allowed to inline, run the action on this thread.
if (canInlineContinuationTask &&
m_syncContext == SynchronizationContext.Current)
{
RunCallback(GetInvokeActionCallback(), m_action, ref Task.t_currentTask);
}
// Otherwise, Post the action back to the SynchronizationContext.
else
{
TplEventSource log = TplEventSource.Log;
if (log.IsEnabled())
{
m_continuationId = Task.NewId();
log.AwaitTaskContinuationScheduled((task.ExecutingTaskScheduler ?? TaskScheduler.Default).Id, task.Id, m_continuationId);
}
RunCallback(GetPostActionCallback(), this, ref Task.t_currentTask);
}
// Any exceptions will be handled by RunCallback.
}