Re: [PATCH 2/3] avocado_qemu: add AVOCADO_DEFAULT_ARCH for cross-arch tests

[Daniel Henrique Barboza]

On 1/18/23 12:23, Fabiano Rosas wrote:
> Daniel Henrique Barboza <dbarboza@ventanamicro.com> writes:
>
> > All avocado tests that are arch agnostic (i.e. does not set an 'arch'
> > tag) are run with arch=None in pick_default_qemu_bin(), and then 'arch'
> > is set to os.uname()[4], meaning that it will take the arch of the
> > running host.
> >
> > This means that if one compiles QEMU binaries for non-x86 targets on an
> > x86 machine, and then run 'make check-avocado', all arch agnostic tests
> > will be cancelled because there's no qemu-system-x86_64 to be found.
> >
> > There is no particular reason to not allow these tests to be run with
> > other arch binaries in a x86_64 host. Allow the developer to do it by
> > adding a a new env variable called AVOCADO_DEFAULT_ARCH. Any 'arch' that
> > is set by this variable will take precedence of setting it via
> > os.uname()[4]. We can then run non-x86 binaries tests in a x86_64 host
> > as follows:
> >
> > $ AVOCADO_DEFAULT_ARCH=riscv64 make check-avocado
> > (...)
> > RESULTS: PASS 11 | ERROR 0 | FAIL 0 | SKIP 1 | WARN 0 | INTERRUPT 0 | CANCEL 0
> I don't understand why tags don't solve the problem. We
> are already passing a tag for each target:
>
> ifndef AVOCADO_TAGS
>         AVOCADO_CMDLINE_TAGS=$(patsubst %-softmmu,-t arch:%, \
>                                                  $(filter %-softmmu,$(TARGETS)))
> else
>         AVOCADO_CMDLINE_TAGS=$(addprefix -t , $(AVOCADO_TAGS))
> endif
>
> I then tried to tag migration.py with:
>
>      :avocado: tags=arch:x86_64
>      :avocado: tags=arch:aarch64
>
> On an x86_64 machine with target-list=x86_64-softmmu,aarch64-softmmu,
> only the x86_64 test runs. Even if I remove the x86_64 tag from the
> avocado line. Possibly due to the --filter-by-tags-include-empty
> options. But I would expect a second run with aarch64, even if it
> failed.

I can give some light in this bit. tests/avocado/avocado_qemu/__init__.py,
setUp() from  "class QemuBaseTest":


    def setUp(self, bin_prefix):
        self.arch = self.params.get('arch',
default=self._get_unique_tag_val('arch'))


So what you did there:

:avocado: tags=arch:x86_64
:avocado: tags=arch:aarch64

Will result in "self.arch = None"  because 'arch' is not an unique tag. This 
has the
same effect as giving no 'arch' tags at all.

In fact, all avocado tags fetched from the test files works the same way. If 
the tag
isn't unique it's considered None.

It is worth mentioning that the docs mentions that the 'arch' tag must be 
unique:

=====
The ``arch`` attribute will be set to the test parameter of the same
name.  If one is not given explicitly, it will either be set to
``None``, or, if the test is tagged with one (and only one)
``:avocado: tags=arch:VALUE`` tag, it will be set to ``VALUE``.
=====

But it doesn't mention that having multiple 'arch' tags will have the same 
effect
as having no 'arch' tag though.


> If I use only:
>
>      :avocado: tags=arch:riscv
>
> and run:
>
> python3 -m avocado --show=app run -t arch:riscv -t arch:x86_64 --failfast 
> ../tests/avocado/migration.py
>
> Then it complains about the binary, but the x86_64 binary is present! So
> it looked at the tag after all:
>
> CANCEL: No QEMU binary defined or found in the build tree for arch riscv
>                                                                     ^^^^^

Yeah, in this case it looked at the 'arch:riscv' tag in the tes,t because it 
was the only 'arch' tag,
and complained that you didn't have RISC-V binaries because it actually tried 
to find them.

Also, what you did there with the "-t arch:riscv -t arch:x86_64" is "run this 
avocado
test if the test tags matches these". There is no way of "assigning" a different
arch/machine/etc via these command line tags. Probably this wasn't your 
intention
at all but I'd rather mention it to be safe.


Thanks,

Daniel



> I don't know how to make this work, but I feel there should be a way to
> have the framework select the correct test AND pass the correct arch
> parameter along.