run-vmtest: introduce run-vmtest.env

[theihor]

Update run-vmtest action to source $VMTEST_CONFIGS/run-vmtest.env when present. For detais read a comment in ci/vmtest/configs/run-vmtest.env

Add scripts local to run-vmtest that handle the merge of multiple allow/denylists for BPF selftests.

Passing @filename as allow/denylist to test runners, instead of inlining comma-separated test names.

Add test_progs-bpf_gcc as a possible test runner in run-vmtest/run-bpf-selftests.sh

[theihor]

@chantra I got GCC BPF working at #165, and then decided to split it into a couple of PRs. Not all changes there are specific to the GCC support, like this one.

[theihor]

vmtest CI passes: kernel-patches/vmtest#326

[chantra]

LGTM overall aside from the fact that I don't think this works correctly as is.

Is there a way to update https://github.com/libbpf/ci/blob/main/run-vmtest/action.yml or a README to document those environment variables needed by run-vmtest.env?

Also, I suppose this needs to be released in a version manner right? e.g landing this into main would break CI as https://github.com/kernel-patches/vmtest/blob/78dc9a42e4c3cdbad127814f91219ee20e40dbf2/.github/workflows/kernel-test.yml#L67 fir instance, is unaware of this yet.

[theihor]

@chantra I added "unit tests" for run-vmtest, and rewrote the "merge lists" script. Please take a look when you get a chance.

[chantra]

Thanks, there is an issue in the rewritten script which was also surfaced by CI, but otherwise this looks go to go.

[theihor]

@chantra Didn't answer these in the first pass through your comments. Answering below.

Is there a way to update https://github.com/libbpf/ci/blob/main/run-vmtest/action.yml or a README to document those environment variables needed by run-vmtest.env?

It's tricky. run-vmtest action doesn't really care about the variables used by run-vmtest.env. It's simple "source", so whatever is in the file will be read.

Presumably, author of run-vmtest.env is also an author of a workflow calling libbpf/ci/run-vmtest action, and so they should know what variables to set.

On the other hand, there are SELFTESTS_BPF_{ALLOW,DENY}LIST_FILES, which is what run-vmtest.env must export (if it exists), because prepare-bpf-selftests.sh depends on this...

I think you're right, a note about this in the readme is warranted.

Also, I suppose this needs to be released in a version manner right? e.g landing this into main would break CI as https://github.com/kernel-patches/vmtest/blob/78dc9a42e4c3cdbad127814f91219ee20e40dbf2/.github/workflows/kernel-test.yml#L67 fir instance, is unaware of this yet.

Yes. This is not an issue for a while now. BPF CI is pinned to v2 currently, so a push to main won't break anything. I usually push to main, then check the update on vmtest, then update the current tag or push a new one (depending on wethere changes are significant).

[theihor]

vmtest pipeline has passed: https://github.com/kernel-patches/vmtest/actions/runs/12776803904

Merging now.