Hi Brendan,
On 9/13/19 3:02 PM, Brendan Higgins wrote:
Hey Knut and Shuah,
Following up on our offline discussion on Wednesday night:
Awesome. Thanks for doing this.
We decided that it would make sense for Knut to try to implement Hybrid
Testing (testing that crosses the kernel userspace boundary) that he
introduced here[1] on top of the existing KUnit infrastructure.
We discussed several possible things in the kernel that Knut could test
with the new Hybrid Testing feature as an initial example. Those were
(in reverse order of expected difficulty):
1. RDS (Reliable Datagram Sockets) - We decided that, although this was
one of the more complicated subsystems to work with, it was probably
the best candidate for Knut to start with because it was in desperate
need of better testing, much of the testing would require crossing
the kernel userspace boundary to be effective, and Knut has access to
RDS (since he works at Oracle).
2. KMOD - Probably much simpler than RDS, and the maintainer, Luis
Chamberlain (CC'ed) would like to see better testing here, but
probably still not as good as RDS because it is in less dire need of
testing, collaboration on this would be more difficult, and Luis is
currently on an extended vacation. Luis and I had already been
discussing testing KMOD here[2].
3. IP over USB - Least desirable option, but still possible. More
complicated than KMOD, and not as easy to collaborate on as RDS.
I don't really think we discussed how this would work. I remember that I
mentioned that it would be easier if I sent out a patch that
centralizes where KUnit tests are dispatched from in the kernel; I will
try to get an RFC for that out, probably sometime next week. That should
provide a pretty straightforward place for Knut to move his work on top
of.
That will be awesome.
The next question is what the userspace component of this should look
like. To me it seems like we should probably have the kselftest test
runner manage when the test gets run, and collecting and reporting the
result of the test, but I think Knut has thought more about this than I,
and Shuah is the kselftest maintainer, so I am guessing this will
probably mostly be a discussion between the two of you.
Yes. This is what I have in mind.
So I think we have a couple of TODOs between us:
Brendan:
- Need to send out patch that provides a single place where all tests
are dispatched from.
Knut:
- Start splitting out the hybrid test stuff from the rest of the RFC
you sent previously.
Knut and Shuah:
- Start figuring out what the userspace component of this will look
like.
Once Knut decides which one of the above options he chooses and sends me
RFC patches, we can start discussing the details based on the RFC.
thanks,
-- Shuah
