Measuring Safety Critical Latency Sources using Linux Kernel eBPF Tracing

With the advent of new, ever more complex requirements for the automotive industry and its suppliers (mainly arising due to a demand for fully autonomous driving), a gradual shift from the established software architecture and hardware on to complex multi-core embedded microprocessors and complex (POSIX-compatible) operating systems is happening. As a highly competitive sector, the pressure to reduce manufacturing costs and part count additionally forces a consolidation of more functions into one single, higher performance embedded computing unit(often from different suppliers and with different base system requirements), while still requiring state-of-the-art functional safety and certification (ASIL, ISO26262). As a direct consequence, a coexistence of (soft-)real-time components and lower priority software on the same hardware leads to a mixedcriticality system. The latencies achievable in this system directly influence the safety, and two OS-related sources of latencies in a sample automotive framework architecture will be quantified using bpftrace, a Linux Kernel tracing solution. For one of the latencies, a separate validation using A/B tests will be performed, and we can show the reliability and low overhead of bpftrace for latency tests in the kernel.