EDF-Like Scheduling for Self-Suspending Real-Time Tasks

In real-time systems, schedulability tests are utilized to provide timing guarantees. However, for self-suspending task sets, current suspension-aware schedulability tests are limited to Task-Level Fixed-Priority (TFP) scheduling or Earliest-Deadline-First (EDF) with constrained-deadline task systems. In this work we provide a unifying schedulability test for the uniprocessor version of Global EDF-Like (GEL) schedulers and arbitrary-deadline task sets. A large body of existing scheduling algorithms can be considered as EDF-Like, such as EDF, First-In-First-Out (FIFO), Earliest-Quasi-Deadline-First (EQDF) and Suspension-Aware EDF (SAEDF). Therefore, the unifying schedulability test is applicable to those algorithms. Moreover, the schedulability test can be applied to TFP scheduling as well.

Our analysis is the first suspension-aware schedulability test applicable to arbitrary-deadline sporadic real-time task systems under Job-Level Fixed-Priority (JFP) scheduling, such as EDF. Moreover, it is the first unifying suspension-aware schedulability test framework that covers a wide range of scheduling algorithms. Through numerical simulations, we show that the schedulability test outperforms the state of the art for EDF under constraineddeadline scenarios. Moreover, we demonstrate the performance of different configurations under EQDF and SAEDF.