1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2021 Facebook */
3 #include <test_progs.h>
4 #include "test_legacy_printk.skel.h"
5
execute_one_variant(bool legacy)6 static int execute_one_variant(bool legacy)
7 {
8 struct test_legacy_printk *skel;
9 int err, zero = 0, my_pid = getpid(), res, map_fd;
10
11 skel = test_legacy_printk__open();
12 if (!ASSERT_OK_PTR(skel, "skel_open"))
13 return -errno;
14
15 bpf_program__set_autoload(skel->progs.handle_legacy, legacy);
16 bpf_program__set_autoload(skel->progs.handle_modern, !legacy);
17
18 err = test_legacy_printk__load(skel);
19 /* no ASSERT_OK, we expect one of two variants can fail here */
20 if (err)
21 goto err_out;
22
23 if (legacy) {
24 map_fd = bpf_map__fd(skel->maps.my_pid_map);
25 err = bpf_map_update_elem(map_fd, &zero, &my_pid, BPF_ANY);
26 if (!ASSERT_OK(err, "my_pid_map_update"))
27 goto err_out;
28 err = bpf_map_lookup_elem(map_fd, &zero, &res);
29 } else {
30 skel->bss->my_pid_var = my_pid;
31 }
32
33 err = test_legacy_printk__attach(skel);
34 if (!ASSERT_OK(err, "skel_attach"))
35 goto err_out;
36
37 usleep(1); /* trigger */
38
39 if (legacy) {
40 map_fd = bpf_map__fd(skel->maps.res_map);
41 err = bpf_map_lookup_elem(map_fd, &zero, &res);
42 if (!ASSERT_OK(err, "res_map_lookup"))
43 goto err_out;
44 } else {
45 res = skel->bss->res_var;
46 }
47
48 if (!ASSERT_GT(res, 0, "res")) {
49 err = -EINVAL;
50 goto err_out;
51 }
52
53 err_out:
54 test_legacy_printk__destroy(skel);
55 return err;
56 }
57
test_legacy_printk(void)58 void test_legacy_printk(void)
59 {
60 /* legacy variant should work everywhere */
61 ASSERT_OK(execute_one_variant(true /* legacy */), "legacy_case");
62
63 /* execute modern variant, can fail the load on old kernels */
64 execute_one_variant(false);
65 }
66
