Location of test kernel drivers in tree?

[Garrett Cooper]

Hi all,
    I need to do some KPI verification and hook that into ATF / kyua.
Since we don't have RUMP [yet] from NetBSD, I would typically write a
simple, one-off test driver, hook it into the kernel build and have a
piece of C or shell code that pokes directly at the driver to get
access to kernel interfaces.
    I was wondering if it made sense to put all test drivers into
sys/tests/<module-name>/..., e.g.
sys/tests/test_memguard/{Makefile,test_memguard.c}, etc. Is there an
alternative approach that others use to solve this problem?
Thanks!
-Garrett