[LITMUS^RT] Budget Consumed By Jobs In Ready Queue

[Björn Brandenburg]

On Aug 23, 2012, at 9:31 PM, Jeremy Erickson wrote:

> I discovered, however, that the same BUG_ON statement is triggered in 2012.2 with the standard GSN-EDF plugin.  That seems incorrect to me - a job should only be in the release or ready queue if it is not executing, in which case it should not be consuming any budget.

No, GSN-EDF implements link-based scheduling to support non-preemptive sections. A job is in the ready queue if it is not _linked_. A linked job may still be scheduled, either while it is non-preemptive or when the actual system is still catching up to the ideal system (e.g., if the rescheduling IPI is still in flight).

Thus, queued jobs may consume budget since they could still be scheduled (for some short time).

- Björn