bpf/prog_tests/pe_preserve_elems.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /* Copyright (c) 2019 Facebook */
0003 #include <test_progs.h>
0004 #include <linux/bpf.h>
0005 #include "test_pe_preserve_elems.skel.h"
0006
0007 static int duration;
0008
0009 static void test_one_map(struct bpf_map *map, struct bpf_program *prog,
0010              bool has_share_pe)
0011 {
0012     int err, key = 0, pfd = -1, mfd = bpf_map__fd(map);
0013     DECLARE_LIBBPF_OPTS(bpf_test_run_opts, opts);
0014     struct perf_event_attr attr = {
0015         .size = sizeof(struct perf_event_attr),
0016         .type = PERF_TYPE_SOFTWARE,
0017         .config = PERF_COUNT_SW_CPU_CLOCK,
0018     };
0019
0020     pfd = syscall(__NR_perf_event_open, &attr, 0 /* pid */,
0021               -1 /* cpu 0 */, -1 /* group id */, 0 /* flags */);
0022     if (CHECK(pfd < 0, "perf_event_open", "failed\n"))
0023         return;
0024
0025     err = bpf_map_update_elem(mfd, &key, &pfd, BPF_ANY);
0026     close(pfd);
0027     if (CHECK(err < 0, "bpf_map_update_elem", "failed\n"))
0028         return;
0029
0030     err = bpf_prog_test_run_opts(bpf_program__fd(prog), &opts);
0031     if (CHECK(err < 0, "bpf_prog_test_run_opts", "failed\n"))
0032         return;
0033     if (CHECK(opts.retval != 0, "bpf_perf_event_read_value",
0034           "failed with %d\n", opts.retval))
0035         return;
0036
0037     /* closing mfd, prog still holds a reference on map */
0038     close(mfd);
0039
0040     err = bpf_prog_test_run_opts(bpf_program__fd(prog), &opts);
0041     if (CHECK(err < 0, "bpf_prog_test_run_opts", "failed\n"))
0042         return;
0043
0044     if (has_share_pe) {
0045         CHECK(opts.retval != 0, "bpf_perf_event_read_value",
0046               "failed with %d\n", opts.retval);
0047     } else {
0048         CHECK(opts.retval != -ENOENT, "bpf_perf_event_read_value",
0049               "should have failed with %d, but got %d\n", -ENOENT,
0050               opts.retval);
0051     }
0052 }
0053
0054 void test_pe_preserve_elems(void)
0055 {
0056     struct test_pe_preserve_elems *skel;
0057
0058     skel = test_pe_preserve_elems__open_and_load();
0059     if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
0060         return;
0061
0062     test_one_map(skel->maps.array_1, skel->progs.read_array_1, false);
0063     test_one_map(skel->maps.array_2, skel->progs.read_array_2, true);
0064
0065     test_pe_preserve_elems__destroy(skel);
0066 }