On 17/08/2022 09:19, Ramon Fried wrote:
On Wed, Aug 17, 2022 at 7:43 AM David Gow <davidgow@xxxxxxxxxx> wrote:
On Mon, Aug 15, 2022 at 5:16 PM Ramon Fried <rfried.dev@xxxxxxxxx> wrote:
Hi.
I implemented a test suite that checks a platform driver, that's the
only way I can test interrupts behavior in the code.
Because it's a platform, I can't use kunit_test_suite(), so I call
__kunit_test_suites_init() as part of the platform driver probe
function.
This works fine but has the following problems.
"TAP version 14" string is not printed and it's impossible to parse
the results using the script.
In addition, the suite is not displayed in /sys/kernel/debug/kunit.
It would be my pleasure to provide a patch that fixes this, I just
wanted to make sure that my testing strategy makes sense.
Thanks,
Ramon
Hi Ramon,
Thanks for reaching out. Calling __kunit_test_suites_init() directly
is not something we'd recommend (and are trying desperately to remove
existing uses), so several of the issues re: the "TAP version 14"
string et al are side effects of calling what is supposed to be an
internal KUnit function manually.
That being said, we definitely do want to make testing platform
drivers as convenient as possible. I'm not sure why kunit_test_suite()
doesn't work for you for platform drivers: are you just missing some
way of instantiating the device from within a test context?
I know Brendan has experimented with some hardware faking code, for
which there's some example use here:
https://kunit-review.googlesource.com/c/linux/+/5275
(Note that you'll need to look at the other patches in the 'relation
chain' for dependencies.)
Equally, I've experimented a bit with testing old soundcard drivers
(via a platform device) here, which may be an easier way to look
through:
https://github.com/sulix/linux/commit/4e1620c86553b9edde7f032318cf417dc13e4d26
Note that neither of those examples are anything other than
experiments, so may not work as-is, or be ideal.
Otherwise, we're always happy to accept patches, though again, if
there's any way of getting your tests working without a direct call to
__kunit_test_suites_init() --- even if that would require patches to
work --- that'd be preferable on our end.
Cheers,
-- David
Hi David,
Thanks for replying.
I looked at the examples you shared, and they all fake the actual device.
My intention is to actually interact with the real device. - get a
real interrupt, etc.
Is it wrong, was the intention that the platform device be mocked ?
Thanks,
Ramon.
Hi, Ramon,
I particularly don't condemn writing tests that require hardware, but
they're best avoided, mostly to facilitate running those tests.
Can you share your code?
I would be happy to take a look if its not a problem for you!
Kind regards,
Tales
