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

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* Copyright (c) 2019 Facebook */
   3 #include <test_progs.h>
   4 #include <linux/bpf.h>
   5 #include "test_pe_preserve_elems.skel.h"
   6
   7 static int duration;
   8
   9 static void test_one_map(struct bpf_map *map, struct bpf_program *prog,
  10                          bool has_share_pe)
  11 {
  12         int err, key = 0, pfd = -1, mfd = bpf_map__fd(map);
  13         DECLARE_LIBBPF_OPTS(bpf_test_run_opts, opts);
  14         struct perf_event_attr attr = {
  15                 .size = sizeof(struct perf_event_attr),
  16                 .type = PERF_TYPE_SOFTWARE,
  17                 .config = PERF_COUNT_SW_CPU_CLOCK,
  18         };
  19
  20         pfd = syscall(__NR_perf_event_open, &attr, 0 /* pid */,
  21                       -1 /* cpu 0 */, -1 /* group id */, 0 /* flags */);
  22         if (CHECK(pfd < 0, "perf_event_open", "failed\n"))
  23                 return;
  24
  25         err = bpf_map_update_elem(mfd, &key, &pfd, BPF_ANY);
  26         close(pfd);
  27         if (CHECK(err < 0, "bpf_map_update_elem", "failed\n"))
  28                 return;
  29
  30         err = bpf_prog_test_run_opts(bpf_program__fd(prog), &opts);
  31         if (CHECK(err < 0, "bpf_prog_test_run_opts", "failed\n"))
  32                 return;
  33         if (CHECK(opts.retval != 0, "bpf_perf_event_read_value",
  34                   "failed with %d\n", opts.retval))
  35                 return;
  36
  37         /* closing mfd, prog still holds a reference on map */
  38         close(mfd);
  39
  40         err = bpf_prog_test_run_opts(bpf_program__fd(prog), &opts);
  41         if (CHECK(err < 0, "bpf_prog_test_run_opts", "failed\n"))
  42                 return;
  43
  44         if (has_share_pe) {
  45                 CHECK(opts.retval != 0, "bpf_perf_event_read_value",
  46                       "failed with %d\n", opts.retval);
  47         } else {
  48                 CHECK(opts.retval != -ENOENT, "bpf_perf_event_read_value",
  49                       "should have failed with %d, but got %d\n", -ENOENT,
  50                       opts.retval);
  51         }
  52 }
  53
  54 void test_pe_preserve_elems(void)
  55 {
  56         struct test_pe_preserve_elems *skel;
  57
  58         skel = test_pe_preserve_elems__open_and_load();
  59         if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
  60                 return;
  61
  62         test_one_map(skel->maps.array_1, skel->progs.read_array_1, false);
  63         test_one_map(skel->maps.array_2, skel->progs.read_array_2, true);
  64
  65         test_pe_preserve_elems__destroy(skel);
  66 }