On Sun, Mar 20, 2022 at 06:02:53PM +0100, Jonathan Cameron wrote:
Very interesting bit of work. My current approach for similar testing is to write a qemu model for the hardware, but that currently requires carefully crafted tests. Most of the time I'm only doing that to verify refactoring of existing drivers.
Thank you for taking a look!
One thing that makes me nervous here is the python element though as I've not written significant python in about 20 years. That is going to be a burden for kernel developers and maintainers... Nothing quite like badly written tests to make for a mess in the long run and I suspect my python for example would be very very badly written :)
There's a bunch of static checkers to ensure that the code follows some basic guidelines, and CI can check that the tests work consistently, and also calculate metrics such as test execution time and code coverage, so even non-idiomatic Python in the tests wouldn't be entirely broken.
And unlike driver code, if the tests for a particular driver later do turn out to be bad (in what way?), we could just throw those particular tests out without breaking anybody's system.
Cut and paste will of course get us a long way...
Isn't some amount of copy/paste followed by modification to be expected even if the framework is written in say C (just as there's already copy/paste + modification involved when writing drivers)?
As for the core logic of individual driver tests excluding the framework bits, I have a hard time imagining what Python syntax looks like to someone with no knowledge of Python, so yes, I guess it's going to be harder to review.
I dream of a world where every driver is testable by people with out hardware but I fear it may be a while yet. Hopefully this will get us a little closer!
I more or less follow what is going on here (good docs btw in the earlier patch definitely helped).
So far I'm thoroughly in favour of road test subject to actually being able to review the tests or getting sufficient support to do so. It's a 'how to scale it' question really...
Would rewriting the framework in C and forcing tests to be written in that language mean that maintainers would be able to review tests without external support?