Precise Analysis of Value-Dependent Synchronization in Priority Scheduled Programs

Although priority scheduling in concurrent programs provides a clean way of synchronization, developers still additionally rely on hand-crafted schemes based on integer variables to protect critical sections. We identify a set of sufficient conditions for variables to serve this purpose. We provide efficient methods to verify these conditions, which enable us to construct an enhanced analysis of mutual exclusion in interrupt-driven concurrent programs. All our algorithms are build upon off-the-shelf inter-procedural analyses alone. We have implemented this approach for the analysis of automotive controllers, and demonstrate that it results in a major improvement in the precision of data race detection compared to purely priority-based techniques.