Test various type data dumping operations by comparing expected format with the dumped string; an snprintf-style printf function is used to record the string dumped.
Signed-off-by: Alan Maguire alan.maguire@oracle.com --- tools/testing/selftests/bpf/prog_tests/btf_dump.c | 233 ++++++++++++++++++++++ 1 file changed, 233 insertions(+)
diff --git a/tools/testing/selftests/bpf/prog_tests/btf_dump.c b/tools/testing/selftests/bpf/prog_tests/btf_dump.c index c60091e..262561f4 100644 --- a/tools/testing/selftests/bpf/prog_tests/btf_dump.c +++ b/tools/testing/selftests/bpf/prog_tests/btf_dump.c @@ -232,6 +232,237 @@ void test_btf_dump_incremental(void) btf__free(btf); }
+#define STRSIZE 2048 +#define EXPECTED_STRSIZE 256 + +void btf_dump_snprintf(void *ctx, const char *fmt, va_list args) +{ + char *s = ctx, new[STRSIZE]; + + vsnprintf(new, STRSIZE, fmt, args); + strncat(s, new, STRSIZE); + vfprintf(ctx, fmt, args); +} + +/* skip "enum "/"struct " prefixes */ +#define SKIP_PREFIX(_typestr, _prefix) \ + do { \ + if (strstr(_typestr, _prefix) == _typestr) \ + _typestr += strlen(_prefix) + 1; \ + } while (0) + +int btf_dump_data(struct btf *btf, struct btf_dump *d, + char *ptrtype, __u64 flags, void *ptr, + char *str, char *expectedval) +{ + struct btf_dump_emit_type_data_opts opts = { 0 }; + int ret = 0, cmp; + __s32 type_id; + + opts.sz = sizeof(opts); + opts.compact = true; + if (flags & BTF_F_NONAME) + opts.noname = true; + if (flags & BTF_F_ZERO) + opts.zero = true; + SKIP_PREFIX(ptrtype, "enum"); + SKIP_PREFIX(ptrtype, "struct"); + SKIP_PREFIX(ptrtype, "union"); + type_id = btf__find_by_name(btf, ptrtype); + if (CHECK(type_id <= 0, "find type id", + "no '%s' in BTF: %d\n", ptrtype, type_id)) { + ret = -ENOENT; + goto err; + } + str[0] = '\0'; + ret = btf_dump__emit_type_data(d, type_id, &opts, ptr); + if (CHECK(ret < 0, "btf_dump__emit_type_data", + "failed: %d\n", ret)) + goto err; + + cmp = strncmp(str, expectedval, EXPECTED_STRSIZE); + if (CHECK(cmp, "ensure expected/actual match", + "'%s' does not match expected '%s': %d\n", + str, expectedval, cmp)) + ret = -EFAULT; + +err: + if (ret) + btf_dump__free(d); + return ret; +} + +#define TEST_BTF_DUMP_DATA(_b, _d, _str, _type, _flags, _expected, ...) \ + do { \ + char _expectedval[EXPECTED_STRSIZE] = _expected; \ + char __ptrtype[64] = #_type; \ + char *_ptrtype = (char *)__ptrtype; \ + static _type _ptrdata = __VA_ARGS__; \ + void *_ptr = &_ptrdata; \ + \ + if (btf_dump_data(_b, _d, _ptrtype, _flags, _ptr, \ + _str, _expectedval)) \ + return; \ + } while (0) + +/* Use where expected data string matches its stringified declaration */ +#define TEST_BTF_DUMP_DATA_C(_b, _d, _str, _type, _opts, ...) \ + TEST_BTF_DUMP_DATA(_b, _d, _str, _type, _opts, \ + "(" #_type ")" #__VA_ARGS__, __VA_ARGS__) + +void test_btf_dump_data(void) +{ + struct btf *btf = libbpf_find_kernel_btf(); + char str[STRSIZE]; + struct btf_dump_opts opts = { .ctx = str }; + struct btf_dump *d; + + if (CHECK(!btf, "get kernel BTF", "no kernel BTF found")) + return; + + d = btf_dump__new(btf, NULL, &opts, btf_dump_snprintf); + + if (CHECK(!d, "new dump", "could not create BTF dump")) + return; + + /* Verify type display for various types. */ + + /* simple int */ + TEST_BTF_DUMP_DATA_C(btf, d, str, int, 0, 1234); + TEST_BTF_DUMP_DATA(btf, d, str, int, BTF_F_NONAME, "1234", 1234); + + /* zero value should be printed at toplevel */ + TEST_BTF_DUMP_DATA(btf, d, str, int, 0, "(int)0", 0); + TEST_BTF_DUMP_DATA(btf, d, str, int, BTF_F_NONAME, "0", 0); + TEST_BTF_DUMP_DATA(btf, d, str, int, BTF_F_ZERO, "(int)0", 0); + TEST_BTF_DUMP_DATA(btf, d, str, int, BTF_F_NONAME | BTF_F_ZERO, + "0", 0); + TEST_BTF_DUMP_DATA_C(btf, d, str, int, 0, -4567); + TEST_BTF_DUMP_DATA(btf, d, str, int, BTF_F_NONAME, "-4567", -4567); + + /* simple char */ + TEST_BTF_DUMP_DATA_C(btf, d, str, char, 0, 100); + TEST_BTF_DUMP_DATA(btf, d, str, char, BTF_F_NONAME, "100", 100); + /* zero value should be printed at toplevel */ + TEST_BTF_DUMP_DATA(btf, d, str, char, 0, "(char)0", 0); + TEST_BTF_DUMP_DATA(btf, d, str, char, BTF_F_NONAME, "0", 0); + TEST_BTF_DUMP_DATA(btf, d, str, char, BTF_F_ZERO, "(char)0", 0); + TEST_BTF_DUMP_DATA(btf, d, str, char, BTF_F_NONAME | BTF_F_ZERO, + "0", 0); + + /* simple typedef */ + TEST_BTF_DUMP_DATA_C(btf, d, str, uint64_t, 0, 100); + TEST_BTF_DUMP_DATA(btf, d, str, u64, BTF_F_NONAME, "1", 1); + /* zero value should be printed at toplevel */ + TEST_BTF_DUMP_DATA(btf, d, str, u64, 0, "(u64)0", 0); + TEST_BTF_DUMP_DATA(btf, d, str, u64, BTF_F_NONAME, "0", 0); + TEST_BTF_DUMP_DATA(btf, d, str, u64, BTF_F_ZERO, "(u64)0", 0); + TEST_BTF_DUMP_DATA(btf, d, str, u64, BTF_F_NONAME | BTF_F_ZERO, + "0", 0); + + /* typedef struct */ + TEST_BTF_DUMP_DATA_C(btf, d, str, atomic_t, 0, {.counter = (int)1,}); + TEST_BTF_DUMP_DATA(btf, d, str, atomic_t, BTF_F_NONAME, "{1,}", + {.counter = 1,}); + /* typedef with 0 value should be printed at toplevel */ + TEST_BTF_DUMP_DATA(btf, d, str, atomic_t, 0, "(atomic_t){}", + {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, str, atomic_t, BTF_F_NONAME, "{}", + {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, str, atomic_t, BTF_F_ZERO, + "(atomic_t){.counter = (int)0,}", + {.counter = 0,}); + TEST_BTF_DUMP_DATA(btf, d, str, atomic_t, BTF_F_NONAME | BTF_F_ZERO, + "{0,}", {.counter = 0,}); + /* enum where enum value does (and does not) exist */ + TEST_BTF_DUMP_DATA_C(btf, d, str, enum bpf_cmd, 0, BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA(btf, d, str, enum bpf_cmd, 0, + "(enum bpf_cmd)BPF_MAP_CREATE", 0); + TEST_BTF_DUMP_DATA(btf, d, str, enum bpf_cmd, BTF_F_NONAME, + "BPF_MAP_CREATE", + BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA(btf, d, str, enum bpf_cmd, + BTF_F_NONAME | BTF_F_ZERO, + "BPF_MAP_CREATE", 0); + + TEST_BTF_DUMP_DATA(btf, d, str, enum bpf_cmd, BTF_F_ZERO, + "(enum bpf_cmd)BPF_MAP_CREATE", + BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA(btf, d, str, enum bpf_cmd, + BTF_F_NONAME | BTF_F_ZERO, + "BPF_MAP_CREATE", BPF_MAP_CREATE); + TEST_BTF_DUMP_DATA_C(btf, d, str, enum bpf_cmd, 0, 2000); + TEST_BTF_DUMP_DATA(btf, d, str, enum bpf_cmd, BTF_F_NONAME, + "2000", 2000); + + /* simple struct */ + TEST_BTF_DUMP_DATA_C(btf, d, str, struct btf_enum, 0, + {.name_off = (__u32)3,.val = (__s32)-1,}); + TEST_BTF_DUMP_DATA(btf, d, str, struct btf_enum, BTF_F_NONAME, + "{3,-1,}", + { .name_off = 3, .val = -1,}); + TEST_BTF_DUMP_DATA(btf, d, str, struct btf_enum, BTF_F_NONAME, "{-1,}", + { .name_off = 0, .val = -1,}); + TEST_BTF_DUMP_DATA(btf, d, str, struct btf_enum, + BTF_F_NONAME | BTF_F_ZERO, + "{0,-1,}", + { .name_off = 0, .val = -1,}); + /* empty struct should be printed */ + TEST_BTF_DUMP_DATA(btf, d, str, struct btf_enum, 0, + "(struct btf_enum){}", + { .name_off = 0, .val = 0,}); + TEST_BTF_DUMP_DATA(btf, d, str, struct btf_enum, BTF_F_NONAME, "{}", + { .name_off = 0, .val = 0,}); + TEST_BTF_DUMP_DATA(btf, d, str, struct btf_enum, BTF_F_ZERO, + "(struct btf_enum){.name_off = (__u32)0,.val = (__s32)0,}", + { .name_off = 0, .val = 0,}); + + /* struct with pointers */ + TEST_BTF_DUMP_DATA(btf, d, str, struct list_head, 0, + "(struct list_head){.next = (struct list_head *)0x1,}", + { .next = (struct list_head *)1 }); + /* NULL pointer should not be displayed */ + TEST_BTF_DUMP_DATA(btf, d, str, struct list_head, 0, + "(struct list_head){}", + { .next = (struct list_head *)0 }); + /* struct with char array */ + TEST_BTF_DUMP_DATA(btf, d, str, struct bpf_prog_info, 0, + "(struct bpf_prog_info){.name = (char[])['f','o','o',],}", + { .name = "foo",}); + TEST_BTF_DUMP_DATA(btf, d, str, struct bpf_prog_info, BTF_F_NONAME, + "{['f','o','o',],}", + {.name = "foo",}); + /* leading null char means do not display string */ + TEST_BTF_DUMP_DATA(btf, d, str, struct bpf_prog_info, 0, + "(struct bpf_prog_info){}", + {.name = {'\0', 'f', 'o', 'o'}}); + /* handle non-printable characters */ + TEST_BTF_DUMP_DATA(btf, d, str, struct bpf_prog_info, 0, + "(struct bpf_prog_info){.name = (char[])[1,2,3,],}", + { .name = {1, 2, 3, 0}}); + + /* struct with non-char array */ + TEST_BTF_DUMP_DATA(btf, d, str, struct __sk_buff, 0, + "(struct __sk_buff){.cb = (__u32[])[1,2,3,4,5,],}", + { .cb = {1, 2, 3, 4, 5,},}); + TEST_BTF_DUMP_DATA(btf, d, str, struct __sk_buff, BTF_F_NONAME, + "{[1,2,3,4,5,],}", + { .cb = { 1, 2, 3, 4, 5},}); + /* For non-char, arrays, show non-zero values only */ + TEST_BTF_DUMP_DATA(btf, d, str, struct __sk_buff, 0, + "(struct __sk_buff){.cb = (__u32[])[1,],}", + { .cb = { 0, 0, 1, 0, 0},}); + + /* struct with bitfields */ + TEST_BTF_DUMP_DATA_C(btf, d, str, struct bpf_insn, 0, + {.code = (__u8)1,.dst_reg = (__u8)0x2,.src_reg = (__u8)0x3,.off = (__s16)4,.imm = (__s32)5,}); + TEST_BTF_DUMP_DATA(btf, d, str, struct bpf_insn, BTF_F_NONAME, + "{1,0x2,0x3,4,5,}", + { .code = 1, .dst_reg = 0x2, .src_reg = 0x3, .off = 4, + .imm = 5,}); +} + + void test_btf_dump() { int i;
@@ -245,4 +476,6 @@ void test_btf_dump() { } if (test__start_subtest("btf_dump: incremental")) test_btf_dump_incremental(); + if (test__start_subtest("btf_dump: data")) + test_btf_dump_data(); }