Re: [PATCH] selftests/kselftest/runner.sh: Add 45 second timeout per test

[shuah]

On 9/19/19 3:17 PM, Kees Cook wrote:
> On Thu, Sep 19, 2019 at 02:09:37PM -0600, shuah wrote:
> > On 9/19/19 12:55 PM, Alexandre Belloni wrote:
> > > On 19/09/2019 11:06:44-0700, Kees Cook wrote:
> > > > Commit a745f7af3cbd ("selftests/harness: Add 30 second timeout per
> > > > test") solves the problem of kselftest_harness.h-using binary tests
> > > > possibly hanging forever. However, scripts and other binaries can still
> > > > hang forever. This adds a global timeout to each test script run.
> >
> > Timeout is good, but really tests should not hang. So we have to somehow
> > indicate that the test needs to be fixed.
>
> Totally agreed, which is why I changed the reporting to call out a
> "TIMEOUT" instead of just having it enter the general failure noise.
>
> > This timeout is a band-aid and not real solution for the problem. This
> > arbitrary value doesn't take into account that the test(s) in that
> > particular directory (TARGET) could be running normally and working
> > through all the tests.
>
> Even something that looks like it's making progress may still be hung or
> won't finish in a reasonable amount of time.
>
> > We need some way to differentiate the two cases.
>
> I don't think it's unreasonable to declare that no test should take
> longer than some default amount of time that can be tweaked via a
> "settings" file. It gives the framework the option of easily removing
> tests that take "too long", etc. If the "timeout=..." value was made
> mandatory for each test directory, then the framework could actually
> filter based on expected worst-case run time.
>
> > > > To make this configurable (e.g. as needed in the "rtc" test case),
> > > > include a new per-test-directory "settings" file (similar to "config")
> > > > that can contain kselftest-specific settings. The first recognized field
> > > > is "timeout".
> > >
> > > Seems good to me. I was also wondering whether this is actually
> > > reasonable to have tests running for so long. I wanted to discuss that
> > > at LPC but I missed the session.
> >
> > There is the individual test times and overall kselftest run time. We
> > have lots of tests now and it does take long.
>
> This patch seeks to implement a "timeout for a single test from
> kselftest's perspective". Some "individual" tests have many subtests
> (e.g. anything built with kselftest_harness.h) giving us the whole
> subtest issue. I think my solution here is a good middle ground: we
> specify the max run time for each executed test binary/script.
>
> It's not clear to me if a v2 is needed? Is this patch fine as-is?
>
> Thanks!

v1 is good. I will pull this in for testing. I do like the way it is
done.

thanks,
-- Shuah