Research On Embedded System Testing Based On Fault Injection

With embedded system widespread and increasingly complex, there is growing concern about its reliability. Embedded software testing is the most basic and most effective approach to guarantee the correctness of embedded software and enhance its reliability. However, embedded software is more difficult to be tested than general software. Also, traditional structural testing methods have some shortcomings in reliability testing.Fault injection, the deliberate insertion of faults into an operational system to evaluate fault-tolerant mechanism and determine its response, offers effective solution to the reliability problem. On the basis of the general framework of fault injection, this paper focuses on the input and output domain of the framework and presents a fault injection method especially for embedded systems platform. Based on the combination of layered structure of embedded systems platform and the design of reliability, fault models are established. Then multi-layer fault-injection is implemented in the hardware interface, OS interface and application layer, using embedded platform API. Fault/Failure probability, faults distribution and fault source are used to analyze the testing results. Further more, we use the Fault Tree Analysis method to analyze the fault dependence and calculate failure probability. Finally, a specific application in embedded platform proves the accuracy and feasibility of the testing technology.As a complemental method for traditional testing, the fault injection method described in this paper focuses on the reaction of tested objects under abnormal conditions with invalid parameters. This method improves testing coverage, which further ensures the stability and reliability of embedded systems.