mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-29 05:44:11 +00:00
Code Issues Releases Wiki Activity

selftests/bpf: add __arg_ctx BTF rewrite test

Browse source 
Add a test validating that libbpf uploads BTF and func_info with
rewritten type information for arguments of global subprogs that are
marked with __arg_ctx tag.

Suggested-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240104013847.3875810-10-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Andrii Nakryiko 2024-01-03 17:38:47 -08:00 committed by Alexei Starovoitov
parent 67fe459144
commit 95226f5a36
1 changed files with 106 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

106
tools/testing/selftests/bpf/prog_tests/test_global_funcs.c
View file

@ -20,6 +20,109 @@
#include "test_global_func17.skel.h"
#include "test_global_func_ctx_args.skel.h"
#include "bpf/libbpf_internal.h"
#include "btf_helpers.h"
static void check_ctx_arg_type(const struct btf *btf, const struct btf_param *p)
{
const struct btf_type *t;
const char *s;
t = btf__type_by_id(btf, p->type);
if (!ASSERT_EQ(btf_kind(t), BTF_KIND_PTR, "ptr_t"))
return;
s = btf_type_raw_dump(btf, t->type);
if (!ASSERT_HAS_SUBSTR(s, "STRUCT 'bpf_perf_event_data' size=0 vlen=0",
"ctx_struct_t"))
return;
}
static void subtest_ctx_arg_rewrite(void)
{
struct test_global_func_ctx_args *skel = NULL;
struct bpf_prog_info info;
char func_info_buf[1024] __attribute__((aligned(8)));
struct bpf_func_info_min *rec;
struct btf *btf = NULL;
__u32 info_len = sizeof(info);
int err, fd, i;
skel = test_global_func_ctx_args__open();
if (!ASSERT_OK_PTR(skel, "skel_open"))
return;
bpf_program__set_autoload(skel->progs.arg_tag_ctx_perf, true);
err = test_global_func_ctx_args__load(skel);
if (!ASSERT_OK(err, "skel_load"))
goto out;
memset(&info, 0, sizeof(info));
info.func_info = ptr_to_u64(&func_info_buf);
info.nr_func_info = 3;
info.func_info_rec_size = sizeof(struct bpf_func_info_min);
fd = bpf_program__fd(skel->progs.arg_tag_ctx_perf);
err = bpf_prog_get_info_by_fd(fd, &info, &info_len);
if (!ASSERT_OK(err, "prog_info"))
goto out;
if (!ASSERT_EQ(info.nr_func_info, 3, "nr_func_info"))
goto out;
btf = btf__load_from_kernel_by_id(info.btf_id);
if (!ASSERT_OK_PTR(btf, "obj_kern_btf"))
goto out;
rec = (struct bpf_func_info_min *)func_info_buf;
for (i = 0; i < info.nr_func_info; i++, rec = (void *)rec + info.func_info_rec_size) {
const struct btf_type *fn_t, *proto_t;
const char *name;
if (rec->insn_off == 0)
continue; /* main prog, skip */
fn_t = btf__type_by_id(btf, rec->type_id);
if (!ASSERT_OK_PTR(fn_t, "fn_type"))
goto out;
if (!ASSERT_EQ(btf_kind(fn_t), BTF_KIND_FUNC, "fn_type_kind"))
goto out;
proto_t = btf__type_by_id(btf, fn_t->type);
if (!ASSERT_OK_PTR(proto_t, "proto_type"))
goto out;
name = btf__name_by_offset(btf, fn_t->name_off);
if (strcmp(name, "subprog_ctx_tag") == 0) {
/* int subprog_ctx_tag(void *ctx __arg_ctx) */
if (!ASSERT_EQ(btf_vlen(proto_t), 1, "arg_cnt"))
goto out;
/* arg 0 is PTR -> STRUCT bpf_perf_event_data */
check_ctx_arg_type(btf, &btf_params(proto_t)[0]);
} else if (strcmp(name, "subprog_multi_ctx_tags") == 0) {
/* int subprog_multi_ctx_tags(void *ctx1 __arg_ctx,
* struct my_struct *mem,
* void *ctx2 __arg_ctx)
*/
if (!ASSERT_EQ(btf_vlen(proto_t), 3, "arg_cnt"))
goto out;
/* arg 0 is PTR -> STRUCT bpf_perf_event_data */
check_ctx_arg_type(btf, &btf_params(proto_t)[0]);
/* arg 2 is PTR -> STRUCT bpf_perf_event_data */
check_ctx_arg_type(btf, &btf_params(proto_t)[2]);
} else {
ASSERT_FAIL("unexpected subprog %s", name);
goto out;
}
}
out:
btf__free(btf);
test_global_func_ctx_args__destroy(skel);
}
void test_test_global_funcs(void)
{
RUN_TESTS(test_global_func1);
@ -40,4 +143,7 @@ void test_test_global_funcs(void)
RUN_TESTS(test_global_func16);
RUN_TESTS(test_global_func17);
RUN_TESTS(test_global_func_ctx_args);
if (test__start_subtest("ctx_arg_rewrite"))
subtest_ctx_arg_rewrite();
}