xref: /linux/tools/testing/selftests/bpf/prog_tests/pe_preserve_elems.c (revision 8e07e0e3964ca4e23ce7b68e2096fe660a888942)
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 }
67