SysWCET: Whole-System Response-Time Analysis for Fixed-Priority Real-Time Systems (Outstanding Paper)
SysWCET: Whole-System Response-Time Analysis for Fixed-Priority Real-Time Systems (Outstanding Paper)
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DOI：
10.1109/rtas.2017.37
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发表时间：
2017-04
期刊：
影响因子：
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通讯作者：
Christian J. Dietrich;Peter Wägemann;Peter Ulbrich;Daniel Lohmann
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文献类型：
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作者：
Christian J. Dietrich;Peter Wägemann;Peter Ulbrich;Daniel Lohmann
最坏情况响应时间(WCRT)--从发布到完成实时任务的时间跨度--是实时系统的重要属性。然而，WCRT分析在实践中是复杂的，因为它不仅取决于对最坏情况执行时间(WCET)的现实检查，而且还取决于系统级开销和阻塞/抢占时间。虽然隐式路径枚举技术(IPET)极大地改进了自动WCET分析，但仍然需要使用系统级开销手动汇总结果-这是一个容易出错且繁琐的过程，会产生过于悲观的结果。通过SysWCET，我们为跨多个执行线程、锁、中断服务例程，特别是实时操作系统(RTOS)的自动化WCRT分析提供了一种集成的方法。我们的方法跨越整个系统的单个IPET公式，并利用RTOS和调度器语义来派生跨内核流事实，以便显著减少WCRT分析中的悲观情绪。我们通过针对汽车OSEK-OS标准(ECC1)的SysWCET的全功能实现来评估我们的方法，包括线程、警报、中断服务例程、事件和基于PCP的资源管理。
The worst-case response time (WCRT) – the time span from release to completion of a real-time task – is a crucial property of real-time systems. However, WCRT analysis is complex in practice, as it depends not only on the realistic examination of worst-case execution times (WCET), but also on system-level overheads and blocking/preemption times. While the implicit path enumeration technique (IPET) has greatly improved automated WCET analysis, the resulting values still need to be aggregated manually with the system-level overheads – an errorprone and tedious process that yields overly pessimistic results. With SysWCET, we provide an integrated approach for the automated WCRT analysis across multiple threads of execution, locks, interrupt service routines, and the real-time operating system (RTOS) in particular. Our approach spans a single IPET formulation over the whole system and exploits RTOS and scheduler semantics to derive cross-kernel flow facts in order to significantly reduce pessimism in the WCRT analysis. We evaluate our approach with a fully functional implementation of SysWCET for the automotive OSEK-OS standard (ECC1), including threads, alarms, interrupt-service routines, events, and PCP-based resource management.