Re: [PATCH 2/2] kselftest/alsa: pcm-test: Decrease stream duration from 4 to 2 seconds

[Nícolas F. R. A. Prado]

On Wed, Jun 21, 2023 at 03:39:12PM +0100, Mark Brown wrote:
> On Wed, Jun 21, 2023 at 04:08:47PM +0200, Jaroslav Kysela wrote:
> 
> > I think that the problem is somewhere else here. The overall test timeout
> > should be calculated dynamically. All tests may be queried for the maximal
> > expected interval based on the hardware/software capabilities. It's a bit
> > pitfall to have a fixed time limit where the realtime tests depend on the
> > number of devices.
> 
> I tend to agree here, unfortunately Shuah hasn't responded to queries
> from Nícolas about this which I imagine is what inspired this patch.  We
> also have problems with mixer-test on one of the Dialog CODECs with a
> couple of 64k value controls and no cache only mode.

Yes, exactly. I've tried increasing the timeout for this test to a larger fixed
value previously, and later asked for more information on how to deal with the
kselftest timeout. [1]

Since I didn't hear back, I thought this patch would be a way to at least
mitigate the issue for now, without limiting the test coverage, which was a
concern with having limited scopes for the test.

I've just noticed that in the mean time a way to override the timeout when
running kselftest has been introduced [2], so I suppose we could use that to
work around the timeout limitation in CI systems and be able to run through
completion on the different hardware at the lab. But I still believe, like you
do, that calculating the timeout at runtime based on the hardware would make
much more sense, though if there's such a desire to keep kselftests under the
45s mark, I'm not sure if it would be acceptable.

[1] https://lore.kernel.org/all/5302e70d-cb58-4e70-b44f-ff81b138a2e1@notapiano/
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f6a01213e3f8

Thanks,
Nícolas