Re: [PATCH v3 3/3] kselftest: Add new test for detecting unprobed Devicetree devices

[Nícolas F. R. A. Prado]

On Thu, Dec 07, 2023 at 08:18:49PM +0000, Mark Brown wrote:
> On Mon, Aug 28, 2023 at 05:13:12PM -0400, Nícolas F. R. A. Prado wrote:
> > Introduce a new kselftest to detect devices that were declared in the
> > Devicetree, and are expected to be probed by a driver, but weren't.
> 
> I've been running this in my personal CI for a little while now and I'm
> finding it's pretty marginal for the 45 second default timeout in
> kselftest on some platforms, especially BeagleBone Black though it's not
> just that.  BBB is both slow and has a comprehensive DT which won't help
> matters, there's 253 devices.
> 
> I'm running it from nfsroot which is going to be part of the problem but
> shouldn't be too bad since we're mainly dealing with proc and sysfs and
> hopefully mostly running cached binaries, I'm also using a serial
> console to get the output which is going to add overhead especially with
> a large number odevices with length names.  I'm not sure what the best
> solution is here - a quick glance at the code doesn't ring any alarm
> bells for me, this may just be a reasonable runtime for the test.

Thanks for reporting this. I've experimented a bit and was able to find an
effective optimization and CC'ed it to you [1]. Hopefully it is as effective for
your board and setup as it is for mine. Let me know there.

[1] https://lore.kernel.org/all/20231208133955.483851-1-nfraprado@xxxxxxxxxxxxx

Thanks,
Nícolas