On 12/16/21 2:04 AM, Andrii Nakryiko wrote:
> Add selftests for prog/map/prog+helper feature probing APIs. Prog and
> map selftests are designed in such a way that they will always test all
> the possible prog/map types, based on running kernel's vmlinux BTF enum
> definition. This way we'll always be sure that when adding new BPF
> program types or map types, libbpf will be always updated accordingly to
> be able to feature-detect them.
>
> BPF prog_helper selftest will have to be manually extended with
> interesting and important prog+helper combinations, it's easy, but can't
> be completely automated.
>
> Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
> ---
[...]
> + for (e = btf_enum(t), i = 0, n = btf_vlen(t); i < n; e++, i++) {
> + const char *prog_type_name = btf__str_by_offset(btf, e->name_off);
> + enum bpf_prog_type prog_type = (enum bpf_prog_type)e->val;
> + int res;
> +
> + if (prog_type == BPF_PROG_TYPE_UNSPEC)
> + continue;
> +
> + if (!test__start_subtest(prog_type_name))
> + continue;
> +
> + res = libbpf_probe_bpf_prog_type(prog_type, NULL);
> + ASSERT_EQ(res, 1, prog_type_name);
> + }
I like how easy BTF makes this.
Maybe worth trying to probe one-past-the-end of enum to confirm it fails as
expected?
Regardless,
Acked-by: Dave Marchevsky <davemarchevsky@xxxxxx>
> +cleanup:
> + btf__free(btf);
> +}
[...]
