Mode-Dynamic Task Allocation and Scheduling for an Engine Management Real-Time System Using a Multicore Microcontroller

Abstract

A variety of methodologies to use embedded multicore controllers efficiently has been discussed in the last years. Several assumptions are usually made in the automotive domain, such as static assignment of tasks to the cores. This paper shows an approach for efficient task allocation depending on different system modes. An engine management system (EMS) is used as application example, and the performance improvement compared to static allocation is assessed. The paper is structured as follows: First the control algorithms for the EMS will be classified according to operating modes. The classified algorithms will be allocated to the cores, depending on the operating mode. We identify mode transition points, allowing a reliable switch without neglecting timing requirements. As a next step, it will be shown that a load distribution by mode-dependent task allocation would be better balanced than a static task allocation. All EMS tasks being applied in this paper serve for a 4 cylinder gasoline torque based system including engine low level drivers. The Infineon AURIX microcontroller is used, featuring three cores. Performance evaluation is done by simulation on the chosen abstraction level. The last section of the document will address proposals for future work to measure and reduce the behavioral differences between the simulation and the implementation on the real target.