Re: [PATCH 1/3] KVM: selftests: Use TAP interface in the kvm_binary_stats_test

From: Sean Christopherson
Date: Thu Oct 06 2022 - 21:24:15 EST


On Wed, Oct 05, 2022, Andrew Jones wrote:
> On Tue, Oct 04, 2022 at 11:31:29AM +0200, Thomas Huth wrote:
> > The kvm_binary_stats_test test currently does not have any output (unless
> > one of the TEST_ASSERT statement fails), so it's hard to say for a user
> > how far it did proceed already. Thus let's make this a little bit more
> > user-friendly and include some TAP output via the kselftest.h interface.
>
> I like the idea of switching the entire kvm selftests framework and all
> tests to the ksft TAP interface. But, if we want to do that, then the
> question is whether we should start by partially using it for some tests,
> and then eventually switch over the framework, or whether we should try to
> switch everything at once.
>
> I think I prefer the latter, because without changing the framework we
> can't provide full TAP anyway as TEST_ASSERT exits with 254 instead of 1
> for a fail-exit and it doesn't output a final TAP test summary either.

I would much prefer the latter, e.g. with common entry/exit points[*], much of the
boilerplate can be done once in common code. I bet we could even figure out a way
to have tests default to setting a plan of '1' so that simple tests don't need to
care about TAP at all.

[*] https://lore.kernel.org/all/20220915000448.1674802-2-vannapurve@xxxxxxxxxx