1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2021 Facebook */
3
4#include <test_progs.h>
5#include <network_helpers.h>
6#include "bpf_loop.skel.h"
7
8static void check_nr_loops(struct bpf_loop *skel)
9{
10	struct bpf_link *link;
11
12	link = bpf_program__attach(skel->progs.test_prog);
13	if (!ASSERT_OK_PTR(link, "link"))
14		return;
15
16	/* test 0 loops */
17	skel->bss->nr_loops = 0;
18
19	usleep(1);
20
21	ASSERT_EQ(skel->bss->nr_loops_returned, skel->bss->nr_loops,
22		  "0 loops");
23
24	/* test 500 loops */
25	skel->bss->nr_loops = 500;
26
27	usleep(1);
28
29	ASSERT_EQ(skel->bss->nr_loops_returned, skel->bss->nr_loops,
30		  "500 loops");
31	ASSERT_EQ(skel->bss->g_output, (500 * 499) / 2, "g_output");
32
33	/* test exceeding the max limit */
34	skel->bss->nr_loops = -1;
35
36	usleep(1);
37
38	ASSERT_EQ(skel->bss->err, -E2BIG, "over max limit");
39
40	bpf_link__destroy(link);
41}
42
43static void check_callback_fn_stop(struct bpf_loop *skel)
44{
45	struct bpf_link *link;
46
47	link = bpf_program__attach(skel->progs.test_prog);
48	if (!ASSERT_OK_PTR(link, "link"))
49		return;
50
51	/* testing that loop is stopped when callback_fn returns 1 */
52	skel->bss->nr_loops = 400;
53	skel->data->stop_index = 50;
54
55	usleep(1);
56
57	ASSERT_EQ(skel->bss->nr_loops_returned, skel->data->stop_index + 1,
58		  "nr_loops_returned");
59	ASSERT_EQ(skel->bss->g_output, (50 * 49) / 2,
60		  "g_output");
61
62	bpf_link__destroy(link);
63}
64
65static void check_null_callback_ctx(struct bpf_loop *skel)
66{
67	struct bpf_link *link;
68
69	/* check that user is able to pass in a null callback_ctx */
70	link = bpf_program__attach(skel->progs.prog_null_ctx);
71	if (!ASSERT_OK_PTR(link, "link"))
72		return;
73
74	skel->bss->nr_loops = 10;
75
76	usleep(1);
77
78	ASSERT_EQ(skel->bss->nr_loops_returned, skel->bss->nr_loops,
79		  "nr_loops_returned");
80
81	bpf_link__destroy(link);
82}
83
84static void check_invalid_flags(struct bpf_loop *skel)
85{
86	struct bpf_link *link;
87
88	/* check that passing in non-zero flags returns -EINVAL */
89	link = bpf_program__attach(skel->progs.prog_invalid_flags);
90	if (!ASSERT_OK_PTR(link, "link"))
91		return;
92
93	usleep(1);
94
95	ASSERT_EQ(skel->bss->err, -EINVAL, "err");
96
97	bpf_link__destroy(link);
98}
99
100static void check_nested_calls(struct bpf_loop *skel)
101{
102	__u32 nr_loops = 100, nested_callback_nr_loops = 4;
103	struct bpf_link *link;
104
105	/* check that nested calls are supported */
106	link = bpf_program__attach(skel->progs.prog_nested_calls);
107	if (!ASSERT_OK_PTR(link, "link"))
108		return;
109
110	skel->bss->nr_loops = nr_loops;
111	skel->bss->nested_callback_nr_loops = nested_callback_nr_loops;
112
113	usleep(1);
114
115	ASSERT_EQ(skel->bss->nr_loops_returned, nr_loops * nested_callback_nr_loops
116		  * nested_callback_nr_loops, "nr_loops_returned");
117	ASSERT_EQ(skel->bss->g_output, (4 * 3) / 2 * nested_callback_nr_loops
118		* nr_loops, "g_output");
119
120	bpf_link__destroy(link);
121}
122
123static void check_non_constant_callback(struct bpf_loop *skel)
124{
125	struct bpf_link *link =
126		bpf_program__attach(skel->progs.prog_non_constant_callback);
127
128	if (!ASSERT_OK_PTR(link, "link"))
129		return;
130
131	skel->bss->callback_selector = 0x0F;
132	usleep(1);
133	ASSERT_EQ(skel->bss->g_output, 0x0F, "g_output #1");
134
135	skel->bss->callback_selector = 0xF0;
136	usleep(1);
137	ASSERT_EQ(skel->bss->g_output, 0xF0, "g_output #2");
138
139	bpf_link__destroy(link);
140}
141
142static void check_stack(struct bpf_loop *skel)
143{
144	struct bpf_link *link = bpf_program__attach(skel->progs.stack_check);
145	const int max_key = 12;
146	int key;
147	int map_fd;
148
149	if (!ASSERT_OK_PTR(link, "link"))
150		return;
151
152	map_fd = bpf_map__fd(skel->maps.map1);
153
154	if (!ASSERT_GE(map_fd, 0, "bpf_map__fd"))
155		goto out;
156
157	for (key = 1; key <= max_key; ++key) {
158		int val = key;
159		int err = bpf_map_update_elem(map_fd, &key, &val, BPF_NOEXIST);
160
161		if (!ASSERT_OK(err, "bpf_map_update_elem"))
162			goto out;
163	}
164
165	usleep(1);
166
167	for (key = 1; key <= max_key; ++key) {
168		int val;
169		int err = bpf_map_lookup_elem(map_fd, &key, &val);
170
171		if (!ASSERT_OK(err, "bpf_map_lookup_elem"))
172			goto out;
173		if (!ASSERT_EQ(val, key + 1, "bad value in the map"))
174			goto out;
175	}
176
177out:
178	bpf_link__destroy(link);
179}
180
181void test_bpf_loop(void)
182{
183	struct bpf_loop *skel;
184
185	skel = bpf_loop__open_and_load();
186	if (!ASSERT_OK_PTR(skel, "bpf_loop__open_and_load"))
187		return;
188
189	skel->bss->pid = getpid();
190
191	if (test__start_subtest("check_nr_loops"))
192		check_nr_loops(skel);
193	if (test__start_subtest("check_callback_fn_stop"))
194		check_callback_fn_stop(skel);
195	if (test__start_subtest("check_null_callback_ctx"))
196		check_null_callback_ctx(skel);
197	if (test__start_subtest("check_invalid_flags"))
198		check_invalid_flags(skel);
199	if (test__start_subtest("check_nested_calls"))
200		check_nested_calls(skel);
201	if (test__start_subtest("check_non_constant_callback"))
202		check_non_constant_callback(skel);
203	if (test__start_subtest("check_stack"))
204		check_stack(skel);
205
206	bpf_loop__destroy(skel);
207}
208