You might like Biscuit: https://github.com/mit-pdos/biscuit https://github.com/mit-pdos/biscuit It was specifically written to measure the performance overhead

You might like Biscuit: https://github.com/mit-pdos/biscuit https://github.com/mit-pdos/biscuit It was specifically written to measure the performance overhead of a high-level language in kernel, so it explicitly makes the same design choices as Linux: monolithic, POSIX-compatible. Results look pretty good.