Abstract: 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 complicated 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.

In my talk, I will focus on the latter and the interactions between application tasks and operating system. In a first step, I will present SysWCET, an integrated approach for the automated WCRT analysis across multiple threads of execution, locks, interrupts, and the real-time operating system (RTOS) kernel in particular. SysWCET can derive cross-kernel flow facts and thus significantly reduces analysis pessimism in statically configured systems (e.g., OSEK variants). In the second part, I will then move on to the even more complex task of analyzing dynamically configured real-time systems (e.g., FreeRTOS, RT-Linux). To tackle the resulting complexity, I will detail our first steps towards a context-sensitive analysis of such systems and the System Wcet ANalyser (SWAN). The talk concludes with a live demo of SWAN.

 

Short Bio: Peter Ulbrich is research associate and lecturer at the Systems Software Group, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Germany. He received his diploma and Ph.D. (Dr.-Ing.) from FAU in 2007 and 2014, respectively. His research interests are mainly focused on real-time and dependable systems as well as control/OS co-design. Dr. Ulbrich is a member of GI, ACM, and IEEE.