A profiling method by PCB hooking and its application for memory fault detection in embedded system operational test

Context: An operational test means a system test that examines whether or not all software or hardware components comply with the requirements given to a system which is deployed in an operational environment. Objective: It is a necessary lightweight-profiling method for embedded systems with severe resource restrictions to conduct operational testing. Method: We focus on the Process Control Block as the optimal location to monitor the execution of all processes. We propose a profiling method to collect the runtime execution information of the processes without interrupting the system's operational environment by hacking the Process Control Block information. Based on the proposed method applied to detect runtime memory faults, we develop the operational testing tool AMOS v1.0 which is currently being used in the automobile industry. Results: An industrial field study on 23 models of car-infotainment systems revealed a total of 519 memory faults while only slowing down the system by 0.084-0.132×. We conducted a comparative analysis on representative runtime memory fault detection tools. This analysis result shows our proposed method that has relatively low overhead meets the requirements for operational testing, while other methods failed to satisfy the operational test conditions. Conclusion: We conclude that a lightweight-profiling method for embedded system operational testing can be built around the Process Control Block.