1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include <inttypes.h>
4 #include <api/fs/tracing_path.h>
5 #include <linux/err.h>
6 #include <linux/string.h>
7 #include <sys/types.h>
8 #include <sys/stat.h>
9 #include <fcntl.h>
10 #include "thread_map.h"
11 #include "evsel.h"
12 #include "debug.h"
13 #include "tests.h"
14 #include "util/counts.h"
15 
test__openat_syscall_event(struct test_suite * test __maybe_unused,int subtest __maybe_unused)16 static int test__openat_syscall_event(struct test_suite *test __maybe_unused,
17 				      int subtest __maybe_unused)
18 {
19 	int err = -1, fd;
20 	struct evsel *evsel;
21 	unsigned int nr_openat_calls = 111, i;
22 	struct perf_thread_map *threads = thread_map__new(-1, getpid(), UINT_MAX);
23 	char sbuf[STRERR_BUFSIZE];
24 	char errbuf[BUFSIZ];
25 
26 	if (threads == NULL) {
27 		pr_debug("thread_map__new\n");
28 		return -1;
29 	}
30 
31 	evsel = evsel__newtp("syscalls", "sys_enter_openat");
32 	if (IS_ERR(evsel)) {
33 		tracing_path__strerror_open_tp(errno, errbuf, sizeof(errbuf), "syscalls", "sys_enter_openat");
34 		pr_debug("%s\n", errbuf);
35 		goto out_thread_map_delete;
36 	}
37 
38 	if (evsel__open_per_thread(evsel, threads) < 0) {
39 		pr_debug("failed to open counter: %s, "
40 			 "tweak /proc/sys/kernel/perf_event_paranoid?\n",
41 			 str_error_r(errno, sbuf, sizeof(sbuf)));
42 		goto out_evsel_delete;
43 	}
44 
45 	for (i = 0; i < nr_openat_calls; ++i) {
46 		fd = openat(0, "/etc/passwd", O_RDONLY);
47 		close(fd);
48 	}
49 
50 	if (evsel__read_on_cpu(evsel, 0, 0) < 0) {
51 		pr_debug("evsel__read_on_cpu\n");
52 		goto out_close_fd;
53 	}
54 
55 	if (perf_counts(evsel->counts, 0, 0)->val != nr_openat_calls) {
56 		pr_debug("evsel__read_on_cpu: expected to intercept %d calls, got %" PRIu64 "\n",
57 			 nr_openat_calls, perf_counts(evsel->counts, 0, 0)->val);
58 		goto out_close_fd;
59 	}
60 
61 	err = 0;
62 out_close_fd:
63 	perf_evsel__close_fd(&evsel->core);
64 out_evsel_delete:
65 	evsel__delete(evsel);
66 out_thread_map_delete:
67 	perf_thread_map__put(threads);
68 	return err;
69 }
70 
71 DEFINE_SUITE("Detect openat syscall event", openat_syscall_event);
72