[LITMUS^RT] Litmus Schedulers Error

[Björn Brandenburg]

On Aug 2, 2013, at 8:19 PM, Kevin Burns <kevinpb at vt.edu> wrote:
> 
> I am currently trying to run the base_mt_task and base_task example programs with each scheduler. I have the most recent version of the litmus patch and litmus_rt kernel. I have compiled the kernel with all the schedulers enabled in the config. 
> 
> The issue is that with a select few schedulers the task_mode(LITMUS_RT_TASK) fails with error: Invalid Argument. The select schedulers are Linux, PSN-EDF and P-FP. The others are successful.
> 
> Any thoughts on why this error is selective would be much appretiated. Thanks in advance.

base_mt_task and base_task are intended as templates for writing your own apps. To just run some dummy RT tasks, use rtspin (or rt_launch) instead.

The error that you describe is likely due to the fact that the task resides on the wrong core. Under partitioned / clustered schedulers, the task must migrate to its assigned partition / cluster *before* it attempts to become a real-time task. Check out the -p option in rtspin.

Linux is a dummy plugin that does not support LITMUS^RT tasks. Its primary purpose is to disable LITMUS^RT functionality during boot.

Regards,
Björn

PS: In the future, please contact the mailing list for LITMUS^RT support issues. You'll get more timely answers from the list as many people other than me may be able to help you.