1 // SPDX-License-Identifier: GPL-2.0 2 #include <test_progs.h> 3 4 void test_stacktrace_map(void) 5 { 6 int control_map_fd, stackid_hmap_fd, stackmap_fd, stack_amap_fd; 7 const char *file = "./test_stacktrace_map.o"; 8 int bytes, efd, err, pmu_fd, prog_fd, stack_trace_len; 9 struct perf_event_attr attr = {}; 10 __u32 key, val, duration = 0; 11 struct bpf_object *obj; 12 char buf[256]; 13 14 err = bpf_prog_load(file, BPF_PROG_TYPE_TRACEPOINT, &obj, &prog_fd); 15 if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno)) 16 return; 17 18 /* Get the ID for the sched/sched_switch tracepoint */ 19 snprintf(buf, sizeof(buf), 20 "/sys/kernel/debug/tracing/events/sched/sched_switch/id"); 21 efd = open(buf, O_RDONLY, 0); 22 if (CHECK(efd < 0, "open", "err %d errno %d\n", efd, errno)) 23 goto close_prog; 24 25 bytes = read(efd, buf, sizeof(buf)); 26 close(efd); 27 if (bytes <= 0 || bytes >= sizeof(buf)) 28 goto close_prog; 29 30 /* Open the perf event and attach bpf progrram */ 31 attr.config = strtol(buf, NULL, 0); 32 attr.type = PERF_TYPE_TRACEPOINT; 33 attr.sample_type = PERF_SAMPLE_RAW | PERF_SAMPLE_CALLCHAIN; 34 attr.sample_period = 1; 35 attr.wakeup_events = 1; 36 pmu_fd = syscall(__NR_perf_event_open, &attr, -1 /* pid */, 37 0 /* cpu 0 */, -1 /* group id */, 38 0 /* flags */); 39 if (CHECK(pmu_fd < 0, "perf_event_open", "err %d errno %d\n", 40 pmu_fd, errno)) 41 goto close_prog; 42 43 err = ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0); 44 if (err) 45 goto disable_pmu; 46 47 err = ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); 48 if (err) 49 goto disable_pmu; 50 51 /* find map fds */ 52 control_map_fd = bpf_find_map(__func__, obj, "control_map"); 53 if (control_map_fd < 0) 54 goto disable_pmu; 55 56 stackid_hmap_fd = bpf_find_map(__func__, obj, "stackid_hmap"); 57 if (stackid_hmap_fd < 0) 58 goto disable_pmu; 59 60 stackmap_fd = bpf_find_map(__func__, obj, "stackmap"); 61 if (stackmap_fd < 0) 62 goto disable_pmu; 63 64 stack_amap_fd = bpf_find_map(__func__, obj, "stack_amap"); 65 if (stack_amap_fd < 0) 66 goto disable_pmu; 67 68 /* give some time for bpf program run */ 69 sleep(1); 70 71 /* disable stack trace collection */ 72 key = 0; 73 val = 1; 74 bpf_map_update_elem(control_map_fd, &key, &val, 0); 75 76 /* for every element in stackid_hmap, we can find a corresponding one 77 * in stackmap, and vise versa. 78 */ 79 err = compare_map_keys(stackid_hmap_fd, stackmap_fd); 80 if (CHECK(err, "compare_map_keys stackid_hmap vs. stackmap", 81 "err %d errno %d\n", err, errno)) 82 goto disable_pmu_noerr; 83 84 err = compare_map_keys(stackmap_fd, stackid_hmap_fd); 85 if (CHECK(err, "compare_map_keys stackmap vs. stackid_hmap", 86 "err %d errno %d\n", err, errno)) 87 goto disable_pmu_noerr; 88 89 stack_trace_len = PERF_MAX_STACK_DEPTH * sizeof(__u64); 90 err = compare_stack_ips(stackmap_fd, stack_amap_fd, stack_trace_len); 91 if (CHECK(err, "compare_stack_ips stackmap vs. stack_amap", 92 "err %d errno %d\n", err, errno)) 93 goto disable_pmu_noerr; 94 95 goto disable_pmu_noerr; 96 disable_pmu: 97 error_cnt++; 98 disable_pmu_noerr: 99 ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE); 100 close(pmu_fd); 101 close_prog: 102 bpf_object__close(obj); 103 } 104