1// SPDX-License-Identifier: GPL-2.0
 2/* Copyright (C) 2023. Huawei Technologies Co., Ltd */
 3#include <test_progs.h>
 4
 5#include "normal_map_btf.skel.h"
 6#include "map_in_map_btf.skel.h"
 7
 8static void do_test_normal_map_btf(void)
 9{
10	struct normal_map_btf *skel;
11	int i, err, new_fd = -1;
12	int map_fd_arr[64];
13
14	skel = normal_map_btf__open_and_load();
15	if (!ASSERT_OK_PTR(skel, "open_load"))
16		return;
17
18	err = normal_map_btf__attach(skel);
19	if (!ASSERT_OK(err, "attach"))
20		goto out;
21
22	skel->bss->pid = getpid();
23	usleep(1);
24	ASSERT_TRUE(skel->bss->done, "done");
25
26	/* Use percpu_array to slow bpf_map_free_deferred() down.
27	 * The memory allocation may fail, so doesn't check the returned fd.
28	 */
29	for (i = 0; i < ARRAY_SIZE(map_fd_arr); i++)
30		map_fd_arr[i] = bpf_map_create(BPF_MAP_TYPE_PERCPU_ARRAY, NULL, 4, 4, 256, NULL);
31
32	/* Close array fd later */
33	new_fd = dup(bpf_map__fd(skel->maps.array));
34out:
35	normal_map_btf__destroy(skel);
36	if (new_fd < 0)
37		return;
38	/* Use kern_sync_rcu() to wait for the start of the free of the bpf
39	 * program and use an assumed delay to wait for the release of the map
40	 * btf which is held by other maps (e.g, bss). After that, array map
41	 * holds the last reference of map btf.
42	 */
43	kern_sync_rcu();
44	usleep(4000);
45	/* Spawn multiple kworkers to delay the invocation of
46	 * bpf_map_free_deferred() for array map.
47	 */
48	for (i = 0; i < ARRAY_SIZE(map_fd_arr); i++) {
49		if (map_fd_arr[i] < 0)
50			continue;
51		close(map_fd_arr[i]);
52	}
53	close(new_fd);
54}
55
56static void do_test_map_in_map_btf(void)
57{
58	int err, zero = 0, new_fd = -1;
59	struct map_in_map_btf *skel;
60
61	skel = map_in_map_btf__open_and_load();
62	if (!ASSERT_OK_PTR(skel, "open_load"))
63		return;
64
65	err = map_in_map_btf__attach(skel);
66	if (!ASSERT_OK(err, "attach"))
67		goto out;
68
69	skel->bss->pid = getpid();
70	usleep(1);
71	ASSERT_TRUE(skel->bss->done, "done");
72
73	/* Close inner_array fd later */
74	new_fd = dup(bpf_map__fd(skel->maps.inner_array));
75	/* Defer the free of inner_array */
76	err = bpf_map__delete_elem(skel->maps.outer_array, &zero, sizeof(zero), 0);
77	ASSERT_OK(err, "delete inner map");
78out:
79	map_in_map_btf__destroy(skel);
80	if (new_fd < 0)
81		return;
82	/* Use kern_sync_rcu() to wait for the start of the free of the bpf
83	 * program and use an assumed delay to wait for the free of the outer
84	 * map and the release of map btf. After that, inner map holds the last
85	 * reference of map btf.
86	 */
87	kern_sync_rcu();
88	usleep(10000);
89	close(new_fd);
90}
91
92void test_map_btf(void)
93{
94	if (test__start_subtest("array_btf"))
95		do_test_normal_map_btf();
96	if (test__start_subtest("inner_array_btf"))
97		do_test_map_in_map_btf();
98}