tools/testing/selftests/bpf/prog_tests/stacktrace_map.c

   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 *prog_name = "tracepoint/sched/sched_switch";
   8         int err, prog_fd, stack_trace_len;
   9         const char *file = "./test_stacktrace_map.o";
  10         __u32 key, val, duration = 0;
  11         struct bpf_program *prog;
  12         struct bpf_object *obj;
  13         struct bpf_link *link;
  14
  15         err = bpf_prog_load(file, BPF_PROG_TYPE_TRACEPOINT, &obj, &prog_fd);
  16         if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno))
  17                 return;
  18
  19         prog = bpf_object__find_program_by_title(obj, prog_name);
  20         if (CHECK(!prog, "find_prog", "prog '%s' not found\n", prog_name))
  21                 goto close_prog;
  22
  23         link = bpf_program__attach_tracepoint(prog, "sched", "sched_switch");
  24         if (CHECK(IS_ERR(link), "attach_tp", "err %ld\n", PTR_ERR(link)))
  25                 goto close_prog;
  26
  27         /* find map fds */
  28         control_map_fd = bpf_find_map(__func__, obj, "control_map");
  29         if (control_map_fd < 0)
  30                 goto disable_pmu;
  31
  32         stackid_hmap_fd = bpf_find_map(__func__, obj, "stackid_hmap");
  33         if (stackid_hmap_fd < 0)
  34                 goto disable_pmu;
  35
  36         stackmap_fd = bpf_find_map(__func__, obj, "stackmap");
  37         if (stackmap_fd < 0)
  38                 goto disable_pmu;
  39
  40         stack_amap_fd = bpf_find_map(__func__, obj, "stack_amap");
  41         if (stack_amap_fd < 0)
  42                 goto disable_pmu;
  43
  44         /* give some time for bpf program run */
  45         sleep(1);
  46
  47         /* disable stack trace collection */
  48         key = 0;
  49         val = 1;
  50         bpf_map_update_elem(control_map_fd, &key, &val, 0);
  51
  52         /* for every element in stackid_hmap, we can find a corresponding one
  53          * in stackmap, and vise versa.
  54          */
  55         err = compare_map_keys(stackid_hmap_fd, stackmap_fd);
  56         if (CHECK(err, "compare_map_keys stackid_hmap vs. stackmap",
  57                   "err %d errno %d\n", err, errno))
  58                 goto disable_pmu_noerr;
  59
  60         err = compare_map_keys(stackmap_fd, stackid_hmap_fd);
  61         if (CHECK(err, "compare_map_keys stackmap vs. stackid_hmap",
  62                   "err %d errno %d\n", err, errno))
  63                 goto disable_pmu_noerr;
  64
  65         stack_trace_len = PERF_MAX_STACK_DEPTH * sizeof(__u64);
  66         err = compare_stack_ips(stackmap_fd, stack_amap_fd, stack_trace_len);
  67         if (CHECK(err, "compare_stack_ips stackmap vs. stack_amap",
  68                   "err %d errno %d\n", err, errno))
  69                 goto disable_pmu_noerr;
  70
  71         goto disable_pmu_noerr;
  72 disable_pmu:
  73         error_cnt++;
  74 disable_pmu_noerr:
  75         bpf_link__destroy(link);
  76 close_prog:
  77         bpf_object__close(obj);
  78 }