Re: [PATCH ipsec-next v3 4/9] bpf: selftests: test_loader: Support __btf_path() annotation

Andrii Nakryiko
2023-12-01T23:50:24Z

On Fri, Dec 1, 2023 at 12:24 PM Daniel Xu <dxu@dxuuu.xyz> wrote:
>
> This commit adds support for per-prog btf_custom_path. This is necessary
> for testing CO-RE relocations on non-vmlinux types using test_loader
> infrastructure.
>
> Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
> ---
> tools/testing/selftests/bpf/progs/bpf_misc.h | 1 +
> tools/testing/selftests/bpf/test_loader.c | 7 +++++++
> 2 files changed, 8 insertions(+)
>

Acked-by: Andrii Nakryiko <andrii@kernel.org>

> diff --git a/tools/testing/selftests/bpf/progs/bpf_misc.h b/tools/testing/selftests/bpf/progs/bpf_misc.h
> index 799fff4995d8..2fd59970c43a 100644
> --- a/tools/testing/selftests/bpf/progs/bpf_misc.h
> +++ b/tools/testing/selftests/bpf/progs/bpf_misc.h
> @@ -71,6 +71,7 @@
> #define __retval_unpriv(val) __attribute__((btf_decl_tag("comment:test_retval_unpriv="#val)))
> #define __auxiliary __attribute__((btf_decl_tag("comment:test_auxiliary")))
> #define __auxiliary_unpriv __attribute__((btf_decl_tag("comment:test_auxiliary_unpriv")))
> +#define __btf_path(path) __attribute__((btf_decl_tag("comment:test_btf_path=" path)))
>
> /* Convenience macro for use with 'asm volatile' blocks */
> #define __naked __attribute__((naked))
> diff --git a/tools/testing/selftests/bpf/test_loader.c b/tools/testing/selftests/bpf/test_loader.c
> index a350ecdfba4a..74ceb7877ae2 100644
> --- a/tools/testing/selftests/bpf/test_loader.c
> +++ b/tools/testing/selftests/bpf/test_loader.c
> @@ -27,6 +27,7 @@
> #define TEST_TAG_RETVAL_PFX_UNPRIV "comment:test_retval_unpriv="
> #define TEST_TAG_AUXILIARY "comment:test_auxiliary"
> #define TEST_TAG_AUXILIARY_UNPRIV "comment:test_auxiliary_unpriv"
> +#define TEST_BTF_PATH "comment:test_btf_path="
>
> /* Warning: duplicated in bpf_misc.h */
> #define POINTER_VALUE 0xcafe4all
> @@ -58,6 +59,7 @@ struct test_spec {
> const char *prog_name;
> struct test_subspec priv;
> struct test_subspec unpriv;
> + const char *btf_custom_path;
> int log_level;
> int prog_flags;
> int mode_mask;
> @@ -288,6 +290,8 @@ static int parse_test_spec(struct test_loader *tester,
> goto cleanup;
> update_flags(&spec->prog_flags, flags, clear);
> }
> + } else if (str_has_pfx(s, TEST_BTF_PATH)) {
> + spec->btf_custom_path = s + sizeof(TEST_BTF_PATH) - 1;
> }
> }
>
> @@ -578,6 +582,9 @@ void run_subtest(struct test_loader *tester,
> }
> }
>
> + /* Implicitly reset to NULL if next test case doesn't specify */
> + open_opts->btf_custom_path = spec->btf_custom_path;
> +
> tobj = bpf_object__open_mem(obj_bytes, obj_byte_cnt, open_opts);
> if (!ASSERT_OK_PTR(tobj, "obj_open_mem")) /* shouldn't happen */
> goto subtest_cleanup;
> --
> 2.42.1
>