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

From: Takashi Iwai
Date: Wed Jun 21 2023 - 12:35:40 EST


On Wed, 21 Jun 2023 18:03:22 +0200,
Nícolas F. R. A. Prado wrote:
>
> 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

So, we're back to square... Unless anyone has a strong objection, I'm
inclined to take this as a workaround for 6.5 for now, as the merge
window deadline is coming. We can improve things at the same time for
the future kernel, too.


thanks,

Takashi