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

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <test_progs.h>
   3
   4 void test_tp_attach_query(void)
   5 {
   6         const int num_progs = 3;
   7         int i, j, bytes, efd, err, prog_fd[num_progs], pmu_fd[num_progs];
   8         __u32 duration = 0, info_len, saved_prog_ids[num_progs];
   9         const char *file = "./test_tracepoint.o";
  10         struct perf_event_query_bpf *query;
  11         struct perf_event_attr attr = {};
  12         struct bpf_object *obj[num_progs];
  13         struct bpf_prog_info prog_info;
  14         char buf[256];
  15
  16         for (i = 0; i < num_progs; i++)
  17                 obj[i] = NULL;
  18
  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                 return;
  24         bytes = read(efd, buf, sizeof(buf));
  25         close(efd);
  26         if (CHECK(bytes <= 0 || bytes >= sizeof(buf),
  27                   "read", "bytes %d errno %d\n", bytes, errno))
  28                 return;
  29
  30         attr.config = strtol(buf, NULL, 0);
  31         attr.type = PERF_TYPE_TRACEPOINT;
  32         attr.sample_type = PERF_SAMPLE_RAW | PERF_SAMPLE_CALLCHAIN;
  33         attr.sample_period = 1;
  34         attr.wakeup_events = 1;
  35
  36         query = malloc(sizeof(*query) + sizeof(__u32) * num_progs);
  37         for (i = 0; i < num_progs; i++) {
  38                 err = bpf_prog_load(file, BPF_PROG_TYPE_TRACEPOINT, &obj[i],
  39                                     &prog_fd[i]);
  40                 if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno))
  41                         goto cleanup1;
  42
  43                 bzero(&prog_info, sizeof(prog_info));
  44                 prog_info.jited_prog_len = 0;
  45                 prog_info.xlated_prog_len = 0;
  46                 prog_info.nr_map_ids = 0;
  47                 info_len = sizeof(prog_info);
  48                 err = bpf_obj_get_info_by_fd(prog_fd[i], &prog_info, &info_len);
  49                 if (CHECK(err, "bpf_obj_get_info_by_fd", "err %d errno %d\n",
  50                           err, errno))
  51                         goto cleanup1;
  52                 saved_prog_ids[i] = prog_info.id;
  53
  54                 pmu_fd[i] = syscall(__NR_perf_event_open, &attr, -1 /* pid */,
  55                                     0 /* cpu 0 */, -1 /* group id */,
  56                                     0 /* flags */);
  57                 if (CHECK(pmu_fd[i] < 0, "perf_event_open", "err %d errno %d\n",
  58                           pmu_fd[i], errno))
  59                         goto cleanup2;
  60                 err = ioctl(pmu_fd[i], PERF_EVENT_IOC_ENABLE, 0);
  61                 if (CHECK(err, "perf_event_ioc_enable", "err %d errno %d\n",
  62                           err, errno))
  63                         goto cleanup3;
  64
  65                 if (i == 0) {
  66                         /* check NULL prog array query */
  67                         query->ids_len = num_progs;
  68                         err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, query);
  69                         if (CHECK(err || query->prog_cnt != 0,
  70                                   "perf_event_ioc_query_bpf",
  71                                   "err %d errno %d query->prog_cnt %u\n",
  72                                   err, errno, query->prog_cnt))
  73                                 goto cleanup3;
  74                 }
  75
  76                 err = ioctl(pmu_fd[i], PERF_EVENT_IOC_SET_BPF, prog_fd[i]);
  77                 if (CHECK(err, "perf_event_ioc_set_bpf", "err %d errno %d\n",
  78                           err, errno))
  79                         goto cleanup3;
  80
  81                 if (i == 1) {
  82                         /* try to get # of programs only */
  83                         query->ids_len = 0;
  84                         err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, query);
  85                         if (CHECK(err || query->prog_cnt != 2,
  86                                   "perf_event_ioc_query_bpf",
  87                                   "err %d errno %d query->prog_cnt %u\n",
  88                                   err, errno, query->prog_cnt))
  89                                 goto cleanup3;
  90
  91                         /* try a few negative tests */
  92                         /* invalid query pointer */
  93                         err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF,
  94                                     (struct perf_event_query_bpf *)0x1);
  95                         if (CHECK(!err || errno != EFAULT,
  96                                   "perf_event_ioc_query_bpf",
  97                                   "err %d errno %d\n", err, errno))
  98                                 goto cleanup3;
  99
 100                         /* no enough space */
 101                         query->ids_len = 1;
 102                         err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, query);
 103                         if (CHECK(!err || errno != ENOSPC || query->prog_cnt != 2,
 104                                   "perf_event_ioc_query_bpf",
 105                                   "err %d errno %d query->prog_cnt %u\n",
 106                                   err, errno, query->prog_cnt))
 107                                 goto cleanup3;
 108                 }
 109
 110                 query->ids_len = num_progs;
 111                 err = ioctl(pmu_fd[i], PERF_EVENT_IOC_QUERY_BPF, query);
 112                 if (CHECK(err || query->prog_cnt != (i + 1),
 113                           "perf_event_ioc_query_bpf",
 114                           "err %d errno %d query->prog_cnt %u\n",
 115                           err, errno, query->prog_cnt))
 116                         goto cleanup3;
 117                 for (j = 0; j < i + 1; j++)
 118                         if (CHECK(saved_prog_ids[j] != query->ids[j],
 119                                   "perf_event_ioc_query_bpf",
 120                                   "#%d saved_prog_id %x query prog_id %x\n",
 121                                   j, saved_prog_ids[j], query->ids[j]))
 122                                 goto cleanup3;
 123         }
 124
 125         i = num_progs - 1;
 126         for (; i >= 0; i--) {
 127  cleanup3:
 128                 ioctl(pmu_fd[i], PERF_EVENT_IOC_DISABLE);
 129  cleanup2:
 130                 close(pmu_fd[i]);
 131  cleanup1:
 132                 bpf_object__close(obj[i]);
 133         }
 134         free(query);
 135 }