Extend test_resolve_btfids() to assert that resolve_btfids emits a BTF_KIND_DECL_TAG named "bpf_kfunc" for every kfunc, and "bpf_fastcall" for kfuncs marked KF_FASTCALL. Add a btf_has_decl_tag() helper that scans the output BTF for a decl tag matching name and target. Signed-off-by: Ihor Solodrai --- .../selftests/bpf/prog_tests/resolve_btfids.c | 40 +++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/resolve_btfids.c b/tools/testing/selftests/bpf/prog_tests/resolve_btfids.c index 8482f00046d4..732cfed35e1c 100644 --- a/tools/testing/selftests/bpf/prog_tests/resolve_btfids.c +++ b/tools/testing/selftests/bpf/prog_tests/resolve_btfids.c @@ -12,6 +12,8 @@ #define BTF_DATA_FILE "resolve_btfids.test.o.BTF" +#define DECL_TAG_FASTCALL "bpf_fastcall" +#define DECL_TAG_KFUNC "bpf_kfunc" #define TYPE_ATTR_ARENA "address_space(1)" #ifndef KF_FASTCALL @@ -176,6 +178,28 @@ static int resolve_symbols(struct btf *btf) return 0; } +static bool btf_has_decl_tag(struct btf *btf, const char *tag_name, s32 target_id) +{ + const struct btf_type *t; + const char *name; + int nr, id; + + nr = btf__type_cnt(btf); + for (id = 1; id < nr; id++) { + t = btf__type_by_id(btf, id); + if (!btf_is_decl_tag(t)) + continue; + if (t->type != (__u32)target_id) + continue; + if (btf_decl_tag(t)->component_idx != -1) + continue; + name = btf__name_by_offset(btf, t->name_off); + if (strcmp(name, tag_name) == 0) + return true; + } + return false; +} + static void check_kfunc_set(struct btf_id_set8 *set) { unsigned int i, j; @@ -260,6 +284,22 @@ void test_resolve_btfids(void) check_kfunc_set(&test_kfunc_set); check_kfunc_set(&test_kfunc_set_rev); + /* Check resolve_btfids emitted a bpf_kfunc decl_tag for each kfunc */ + for (i = 0; i < ARRAY_SIZE(kfunc_symbols); i++) { + ASSERT_TRUE(btf_has_decl_tag(btf, DECL_TAG_KFUNC, + kfunc_symbols[i].id), + kfunc_symbols[i].name); + } + + /* Check resolve_btfids emitted bpf_fastcall for KF_FASTCALL kfuncs */ + for (i = 0; i < ARRAY_SIZE(kfunc_symbols); i++) { + if (kfunc_symbols[i].flags & KF_FASTCALL) { + ASSERT_TRUE(btf_has_decl_tag(btf, DECL_TAG_FASTCALL, + kfunc_symbols[i].id), + kfunc_symbols[i].name); + } + } + /* * Check resolve_btfids wrapped exactly the arena-flagged return/args * with the address_space(1) type attribute, and left other -- 2.55.0