1 // SPDX-License-Identifier: GPL-2.0 2 #include <test_progs.h> 3 #include "test_stacktrace_build_id.skel.h" 4 5 void 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 17 retry: 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); 100 101 cleanup: 102 test_stacktrace_build_id__destroy(skel); 103 } 104