Overriding RTX scheduling policy

Hello,
Let me start with what I am trying to do: I want to launch a couple of RTX tasks and to force each task to execute for a constant amount of time, after which the scheduler will select another task to run (round robin scheduling will be nice). I have gotten it to work by blocking all tasks on an event, then waking up the appropriate task using a monitor task when the running task execution period has elapsed. but that requires each task (except the monitor of course) to give up its time slice and wait on an event, while I want it to be transparent to the tasks - a task will loss the CPU because the monitor found out that it exceeded its time slice, without taking any other action. and I do not want to replicate what RTX can already offer (assuming it can). the problem is that as far I as could find in the RL-ARM documentation, RTX does not offer such functionality. do you have an idea how I could better tackle this problem? note: I need to have control over the next task to execute so that I can measure its execution time, unless, of course, there exists a feature that I missed!