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1// SPDX-License-Identifier: GPL-2.0
2#include <test_progs.h>
3#include "test_stacktrace_build_id.skel.h"
4
5void test_stacktrace_build_id(void)
6{
7
8 int control_map_fd, stackid_hmap_fd, stackmap_fd, stack_amap_fd;
9 struct test_stacktrace_build_id *skel;
10 int err, stack_trace_len, build_id_size;
11 __u32 key, prev_key, val, duration = 0;
12 char buf[BPF_BUILD_ID_SIZE];
13 struct bpf_stack_build_id id_offs[PERF_MAX_STACK_DEPTH];
14 int build_id_matches = 0;
15 int i, retry = 1;
16
17retry:
18 skel = test_stacktrace_build_id__open_and_load();
19 if (CHECK(!skel, "skel_open_and_load", "skeleton open/load failed\n"))
20 return;
21
22 err = test_stacktrace_build_id__attach(skel);
23 if (CHECK(err, "attach_tp", "err %d\n", err))
24 goto cleanup;
25
26 /* find map fds */
27 control_map_fd = bpf_map__fd(skel->maps.control_map);
28 stackid_hmap_fd = bpf_map__fd(skel->maps.stackid_hmap);
29 stackmap_fd = bpf_map__fd(skel->maps.stackmap);
30 stack_amap_fd = bpf_map__fd(skel->maps.stack_amap);
31
32 if (CHECK_FAIL(system("dd if=/dev/urandom of=/dev/zero count=4 2> /dev/null")))
33 goto cleanup;
34 if (CHECK_FAIL(system("./urandom_read")))
35 goto cleanup;
36 /* disable stack trace collection */
37 key = 0;
38 val = 1;
39 bpf_map_update_elem(control_map_fd, &key, &val, 0);
40
41 /* for every element in stackid_hmap, we can find a corresponding one
42 * in stackmap, and vise versa.
43 */
44 err = compare_map_keys(stackid_hmap_fd, stackmap_fd);
45 if (CHECK(err, "compare_map_keys stackid_hmap vs. stackmap",
46 "err %d errno %d\n", err, errno))
47 goto cleanup;
48
49 err = compare_map_keys(stackmap_fd, stackid_hmap_fd);
50 if (CHECK(err, "compare_map_keys stackmap vs. stackid_hmap",
51 "err %d errno %d\n", err, errno))
52 goto cleanup;
53
54 build_id_size = read_build_id("urandom_read", buf, sizeof(buf));
55 err = build_id_size < 0 ? build_id_size : 0;
56
57 if (CHECK(err, "read_build_id",
58 "err %d errno %d\n", err, errno))
59 goto cleanup;
60
61 err = bpf_map__get_next_key(skel->maps.stackmap, NULL, &key, sizeof(key));
62 if (CHECK(err, "get_next_key from stackmap",
63 "err %d, errno %d\n", err, errno))
64 goto cleanup;
65
66 do {
67 err = bpf_map_lookup_elem(stackmap_fd, &key, id_offs);
68 if (CHECK(err, "lookup_elem from stackmap",
69 "err %d, errno %d\n", err, errno))
70 goto cleanup;
71 for (i = 0; i < PERF_MAX_STACK_DEPTH; ++i)
72 if (id_offs[i].status == BPF_STACK_BUILD_ID_VALID &&
73 id_offs[i].offset != 0) {
74 if (memcmp(buf, id_offs[i].build_id, build_id_size) == 0)
75 build_id_matches = 1;
76 }
77 prev_key = key;
78 } while (bpf_map__get_next_key(skel->maps.stackmap, &prev_key, &key, sizeof(key)) == 0);
79
80 /* stack_map_get_build_id_offset() is racy and sometimes can return
81 * BPF_STACK_BUILD_ID_IP instead of BPF_STACK_BUILD_ID_VALID;
82 * try it one more time.
83 */
84 if (build_id_matches < 1 && retry--) {
85 test_stacktrace_build_id__destroy(skel);
86 printf("%s:WARN:Didn't find expected build ID from the map, retrying\n",
87 __func__);
88 goto retry;
89 }
90
91 if (CHECK(build_id_matches < 1, "build id match",
92 "Didn't find expected build ID from the map\n"))
93 goto cleanup;
94
95 stack_trace_len = PERF_MAX_STACK_DEPTH *
96 sizeof(struct bpf_stack_build_id);
97 err = compare_stack_ips(stackmap_fd, stack_amap_fd, stack_trace_len);
98 CHECK(err, "compare_stack_ips stackmap vs. stack_amap",
99 "err %d errno %d\n", err, errno);
100
101cleanup:
102 test_stacktrace_build_id__destroy(skel);
103}
1// SPDX-License-Identifier: GPL-2.0
2#include <test_progs.h>
3
4void test_stacktrace_build_id(void)
5{
6 int control_map_fd, stackid_hmap_fd, stackmap_fd, stack_amap_fd;
7 const char *prog_name = "tracepoint/random/urandom_read";
8 const char *file = "./test_stacktrace_build_id.o";
9 int err, prog_fd, stack_trace_len;
10 __u32 key, previous_key, val, duration = 0;
11 struct bpf_program *prog;
12 struct bpf_object *obj;
13 struct bpf_link *link = NULL;
14 char buf[256];
15 int i, j;
16 struct bpf_stack_build_id id_offs[PERF_MAX_STACK_DEPTH];
17 int build_id_matches = 0;
18 int retry = 1;
19
20retry:
21 err = bpf_prog_load(file, BPF_PROG_TYPE_TRACEPOINT, &obj, &prog_fd);
22 if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno))
23 return;
24
25 prog = bpf_object__find_program_by_title(obj, prog_name);
26 if (CHECK(!prog, "find_prog", "prog '%s' not found\n", prog_name))
27 goto close_prog;
28
29 link = bpf_program__attach_tracepoint(prog, "random", "urandom_read");
30 if (CHECK(IS_ERR(link), "attach_tp", "err %ld\n", PTR_ERR(link)))
31 goto close_prog;
32
33 /* find map fds */
34 control_map_fd = bpf_find_map(__func__, obj, "control_map");
35 if (CHECK(control_map_fd < 0, "bpf_find_map control_map",
36 "err %d errno %d\n", err, errno))
37 goto disable_pmu;
38
39 stackid_hmap_fd = bpf_find_map(__func__, obj, "stackid_hmap");
40 if (CHECK(stackid_hmap_fd < 0, "bpf_find_map stackid_hmap",
41 "err %d errno %d\n", err, errno))
42 goto disable_pmu;
43
44 stackmap_fd = bpf_find_map(__func__, obj, "stackmap");
45 if (CHECK(stackmap_fd < 0, "bpf_find_map stackmap", "err %d errno %d\n",
46 err, errno))
47 goto disable_pmu;
48
49 stack_amap_fd = bpf_find_map(__func__, obj, "stack_amap");
50 if (CHECK(stack_amap_fd < 0, "bpf_find_map stack_amap",
51 "err %d errno %d\n", err, errno))
52 goto disable_pmu;
53
54 if (CHECK_FAIL(system("dd if=/dev/urandom of=/dev/zero count=4 2> /dev/null")))
55 goto disable_pmu;
56 if (CHECK_FAIL(system("./urandom_read")))
57 goto disable_pmu;
58 /* disable stack trace collection */
59 key = 0;
60 val = 1;
61 bpf_map_update_elem(control_map_fd, &key, &val, 0);
62
63 /* for every element in stackid_hmap, we can find a corresponding one
64 * in stackmap, and vise versa.
65 */
66 err = compare_map_keys(stackid_hmap_fd, stackmap_fd);
67 if (CHECK(err, "compare_map_keys stackid_hmap vs. stackmap",
68 "err %d errno %d\n", err, errno))
69 goto disable_pmu;
70
71 err = compare_map_keys(stackmap_fd, stackid_hmap_fd);
72 if (CHECK(err, "compare_map_keys stackmap vs. stackid_hmap",
73 "err %d errno %d\n", err, errno))
74 goto disable_pmu;
75
76 err = extract_build_id(buf, 256);
77
78 if (CHECK(err, "get build_id with readelf",
79 "err %d errno %d\n", err, errno))
80 goto disable_pmu;
81
82 err = bpf_map_get_next_key(stackmap_fd, NULL, &key);
83 if (CHECK(err, "get_next_key from stackmap",
84 "err %d, errno %d\n", err, errno))
85 goto disable_pmu;
86
87 do {
88 char build_id[64];
89
90 err = bpf_map_lookup_elem(stackmap_fd, &key, id_offs);
91 if (CHECK(err, "lookup_elem from stackmap",
92 "err %d, errno %d\n", err, errno))
93 goto disable_pmu;
94 for (i = 0; i < PERF_MAX_STACK_DEPTH; ++i)
95 if (id_offs[i].status == BPF_STACK_BUILD_ID_VALID &&
96 id_offs[i].offset != 0) {
97 for (j = 0; j < 20; ++j)
98 sprintf(build_id + 2 * j, "%02x",
99 id_offs[i].build_id[j] & 0xff);
100 if (strstr(buf, build_id) != NULL)
101 build_id_matches = 1;
102 }
103 previous_key = key;
104 } while (bpf_map_get_next_key(stackmap_fd, &previous_key, &key) == 0);
105
106 /* stack_map_get_build_id_offset() is racy and sometimes can return
107 * BPF_STACK_BUILD_ID_IP instead of BPF_STACK_BUILD_ID_VALID;
108 * try it one more time.
109 */
110 if (build_id_matches < 1 && retry--) {
111 bpf_link__destroy(link);
112 bpf_object__close(obj);
113 printf("%s:WARN:Didn't find expected build ID from the map, retrying\n",
114 __func__);
115 goto retry;
116 }
117
118 if (CHECK(build_id_matches < 1, "build id match",
119 "Didn't find expected build ID from the map\n"))
120 goto disable_pmu;
121
122 stack_trace_len = PERF_MAX_STACK_DEPTH
123 * sizeof(struct bpf_stack_build_id);
124 err = compare_stack_ips(stackmap_fd, stack_amap_fd, stack_trace_len);
125 CHECK(err, "compare_stack_ips stackmap vs. stack_amap",
126 "err %d errno %d\n", err, errno);
127
128disable_pmu:
129 bpf_link__destroy(link);
130
131close_prog:
132 bpf_object__close(obj);
133}