SlackCheck: A Linux Kernel Module to Verify Temporal Properties of a Task Schedule

Authors Michele Castrovilli , Enrico Bini

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Author Details

Michele Castrovilli
  • University of Turin, Italy
Enrico Bini
  • University of Turin, Italy

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Michele Castrovilli and Enrico Bini. SlackCheck: A Linux Kernel Module to Verify Temporal Properties of a Task Schedule. In 36th Euromicro Conference on Real-Time Systems (ECRTS 2024). Leibniz International Proceedings in Informatics (LIPIcs), Volume 298, pp. 2:1-2:24, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2024)


The Linux Kernel offers several scheduling classes. From SCHED_DEADLINE down to SCHED_FIFO, SCHED_RR and SCHED_OTHER, the scheduling classes can provide different responsiveness to very diverse user workloads. Still, Linux does not offer any mechanism to take some action upon the violation of temporal constraints at runtime. The lack of such a feature is also due to the difficulty of extending the established notion of deadline to workloads which are not releasing periodic/sporadic jobs. Exploiting the notion of supply functions for any resource schedule, we implemented SlackCheck, a kernel module which is capable to verify at runtime if a given task is assigned a desired amount of resource or not. SlackCheck adds a constant-time check at every scheduling decision and leverages the recent availability of a Runtime Verification engine in the kernel.

Subject Classification

ACM Subject Classification
  • Software and its engineering → Scheduling
  • Theory of computation → Verification by model checking
  • Proper nouns: People, technologies and companies → Linux
  • Computer systems organization → Real-time operating systems
  • Software and its engineering → Operating systems
  • Linux scheduler
  • Runtime verification
  • bounded-delay resource partition
  • supply function
  • service curve
  • real-time calculus
  • network calculus


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