Skip to content

Commit

Permalink
tools/bpf: enhance test_btf file testing to test func info
Browse files Browse the repository at this point in the history 
Change the bpf programs test_btf_haskv.c and test_btf_nokv.c to
have two sections, and enhance test_btf.c test_file feature
to test btf func_info returned by the kernel.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
  • Loading branch information
Yonghong Song authored and Alexei Starovoitov committed Nov 20, 2018
1 parent d7f5b5e commit 999d82c
Show file tree
Hide file tree
Showing 3 changed files with 136 additions and 13 deletions.
117 changes: 108 additions & 9 deletions tools/testing/selftests/bpf/test_btf.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2434,13 +2434,13 @@ static struct btf_file_test file_tests[] = {
},
};

static int file_has_btf_elf(const char *fn)
static int file_has_btf_elf(const char *fn, bool *has_btf_ext)
{
Elf_Scn *scn = NULL;
GElf_Ehdr ehdr;
int ret = 0;
int elf_fd;
Elf *elf;
int ret;

if (CHECK(elf_version(EV_CURRENT) == EV_NONE,
"elf_version(EV_CURRENT) == EV_NONE"))
Expand Down Expand Up @@ -2472,14 +2472,12 @@ static int file_has_btf_elf(const char *fn)
}

sh_name = elf_strptr(elf, ehdr.e_shstrndx, sh.sh_name);
if (!strcmp(sh_name, BTF_ELF_SEC)) {
if (!strcmp(sh_name, BTF_ELF_SEC))
ret = 1;
goto done;
}
if (!strcmp(sh_name, BTF_EXT_ELF_SEC))
*has_btf_ext = true;
}

ret = 0;

done:
close(elf_fd);
elf_end(elf);
Expand All @@ -2489,15 +2487,24 @@ static int file_has_btf_elf(const char *fn)
static int do_test_file(unsigned int test_num)
{
const struct btf_file_test *test = &file_tests[test_num - 1];
const char *expected_fnames[] = {"_dummy_tracepoint",
"test_long_fname_1",
"test_long_fname_2"};
struct bpf_prog_info info = {};
struct bpf_object *obj = NULL;
struct bpf_func_info *finfo;
struct bpf_program *prog;
__u32 info_len, rec_size;
bool has_btf_ext = false;
struct btf *btf = NULL;
void *func_info = NULL;
struct bpf_map *map;
int err;
int i, err, prog_fd;

fprintf(stderr, "BTF libbpf test[%u] (%s): ", test_num,
test->file);

err = file_has_btf_elf(test->file);
err = file_has_btf_elf(test->file, &has_btf_ext);
if (err == -1)
return err;

Expand Down Expand Up @@ -2525,6 +2532,7 @@ static int do_test_file(unsigned int test_num)
err = bpf_object__load(obj);
if (CHECK(err < 0, "bpf_object__load: %d", err))
goto done;
prog_fd = bpf_program__fd(prog);

map = bpf_object__find_map_by_name(obj, "btf_map");
if (CHECK(!map, "btf_map not found")) {
Expand All @@ -2539,9 +2547,100 @@ static int do_test_file(unsigned int test_num)
test->btf_kv_notfound))
goto done;

if (!jit_enabled || !has_btf_ext)
goto skip_jit;

/* get necessary program info */
info_len = sizeof(struct bpf_prog_info);
err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);

if (CHECK(err == -1, "invalid get info (1st) errno:%d", errno)) {
fprintf(stderr, "%s\n", btf_log_buf);
err = -1;
goto done;
}
if (CHECK(info.func_info_cnt != 3,
"incorrect info.func_info_cnt (1st) %d",
info.func_info_cnt)) {
err = -1;
goto done;
}
rec_size = info.func_info_rec_size;
if (CHECK(rec_size < 4,
"incorrect info.func_info_rec_size (1st) %d\n", rec_size)) {
err = -1;
goto done;
}

func_info = malloc(info.func_info_cnt * rec_size);
if (CHECK(!func_info, "out of memeory")) {
err = -1;
goto done;
}

/* reset info to only retrieve func_info related data */
memset(&info, 0, sizeof(info));
info.func_info_cnt = 3;
info.func_info_rec_size = rec_size;
info.func_info = ptr_to_u64(func_info);

err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);

if (CHECK(err == -1, "invalid get info (2nd) errno:%d", errno)) {
fprintf(stderr, "%s\n", btf_log_buf);
err = -1;
goto done;
}
if (CHECK(info.func_info_cnt != 3,
"incorrect info.func_info_cnt (2nd) %d",
info.func_info_cnt)) {
err = -1;
goto done;
}
if (CHECK(info.func_info_rec_size != rec_size,
"incorrect info.func_info_rec_size (2nd) %d",
info.func_info_rec_size)) {
err = -1;
goto done;
}

err = btf_get_from_id(info.btf_id, &btf);
if (CHECK(err, "cannot get btf from kernel, err: %d", err))
goto done;

/* check three functions */
finfo = func_info;
for (i = 0; i < 3; i++) {
const struct btf_type *t;
const char *fname;

t = btf__type_by_id(btf, finfo->type_id);
if (CHECK(!t, "btf__type_by_id failure: id %u",
finfo->type_id)) {
err = -1;
goto done;
}

fname = btf__name_by_offset(btf, t->name_off);
err = strcmp(fname, expected_fnames[i]);
/* for the second and third functions in .text section,
* the compiler may order them either way.
*/
if (i && err)
err = strcmp(fname, expected_fnames[3 - i]);
if (CHECK(err, "incorrect fname %s", fname ? : "")) {
err = -1;
goto done;
}

finfo = (void *)finfo + rec_size;
}

skip_jit:
fprintf(stderr, "OK");

done:
free(func_info);
bpf_object__close(obj);
return err;
}
Expand Down
16 changes: 14 additions & 2 deletions tools/testing/selftests/bpf/test_btf_haskv.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -24,8 +24,8 @@ struct dummy_tracepoint_args {
struct sock *sock;
};

SEC("dummy_tracepoint")
int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
__attribute__((noinline))
static int test_long_fname_2(struct dummy_tracepoint_args *arg)
{
struct ipv_counts *counts;
int key = 0;
Expand All @@ -42,4 +42,16 @@ int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
return 0;
}

__attribute__((noinline))
static int test_long_fname_1(struct dummy_tracepoint_args *arg)
{
return test_long_fname_2(arg);
}

SEC("dummy_tracepoint")
int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
{
return test_long_fname_1(arg);
}

char _license[] SEC("license") = "GPL";
16 changes: 14 additions & 2 deletions tools/testing/selftests/bpf/test_btf_nokv.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -22,8 +22,8 @@ struct dummy_tracepoint_args {
struct sock *sock;
};

SEC("dummy_tracepoint")
int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
__attribute__((noinline))
static int test_long_fname_2(struct dummy_tracepoint_args *arg)
{
struct ipv_counts *counts;
int key = 0;
Expand All @@ -40,4 +40,16 @@ int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
return 0;
}

__attribute__((noinline))
static int test_long_fname_1(struct dummy_tracepoint_args *arg)
{
return test_long_fname_2(arg);
}

SEC("dummy_tracepoint")
int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
{
return test_long_fname_1(arg);
}

char _license[] SEC("license") = "GPL";

0 comments on commit 999d82c

Please sign in to comment.