1// SPDX-License-Identifier: GPL-2.0
2#include <errno.h>
3#include <limits.h>
4#include <stdio.h>
5#include <stdlib.h>
6#include <unistd.h>
7#include <sys/epoll.h>
8#include <util/symbol.h>
9#include <linux/filter.h>
10#include "tests.h"
11#include "debug.h"
12#include "probe-file.h"
13#include "build-id.h"
14#include "util.h"
15
16/* To test SDT event, we need libelf support to scan elf binary */
17#if defined(HAVE_SDT_EVENT) && defined(HAVE_LIBELF_SUPPORT)
18
19#include <sys/sdt.h>
20
21static int target_function(void)
22{
23	DTRACE_PROBE(perf, test_target);
24	return TEST_OK;
25}
26
27/* Copied from builtin-buildid-cache.c */
28static int build_id_cache__add_file(const char *filename)
29{
30	char sbuild_id[SBUILD_ID_SIZE];
31	struct build_id bid;
32	int err;
33
34	err = filename__read_build_id(filename, &bid);
35	if (err < 0) {
36		pr_debug("Failed to read build id of %s\n", filename);
37		return err;
38	}
39
40	build_id__sprintf(&bid, sbuild_id);
41	err = build_id_cache__add_s(sbuild_id, filename, NULL, false, false);
42	if (err < 0)
43		pr_debug("Failed to add build id cache of %s\n", filename);
44	return err;
45}
46
47static char *get_self_path(void)
48{
49	char *buf = calloc(PATH_MAX, sizeof(char));
50
51	if (buf && readlink("/proc/self/exe", buf, PATH_MAX - 1) < 0) {
52		pr_debug("Failed to get correct path of perf\n");
53		free(buf);
54		return NULL;
55	}
56	return buf;
57}
58
59static int search_cached_probe(const char *target,
60			       const char *group, const char *event)
61{
62	struct probe_cache *cache = probe_cache__new(target, NULL);
63	int ret = 0;
64
65	if (!cache) {
66		pr_debug("Failed to open probe cache of %s\n", target);
67		return -EINVAL;
68	}
69
70	if (!probe_cache__find_by_name(cache, group, event)) {
71		pr_debug("Failed to find %s:%s in the cache\n", group, event);
72		ret = -ENOENT;
73	}
74	probe_cache__delete(cache);
75
76	return ret;
77}
78
79static int test__sdt_event(struct test_suite *test __maybe_unused, int subtests __maybe_unused)
80{
81	int ret = TEST_FAIL;
82	char __tempdir[] = "./test-buildid-XXXXXX";
83	char *tempdir = NULL, *myself = get_self_path();
84
85	if (myself == NULL || mkdtemp(__tempdir) == NULL) {
86		pr_debug("Failed to make a tempdir for build-id cache\n");
87		goto error;
88	}
89	/* Note that buildid_dir must be an absolute path */
90	tempdir = realpath(__tempdir, NULL);
91	if (tempdir == NULL)
92		goto error_rmdir;
93
94	/* At first, scan itself */
95	set_buildid_dir(tempdir);
96	if (build_id_cache__add_file(myself) < 0)
97		goto error_rmdir;
98
99	/* Open a cache and make sure the SDT is stored */
100	if (search_cached_probe(myself, "sdt_perf", "test_target") < 0)
101		goto error_rmdir;
102
103	/* TBD: probing on the SDT event and collect logs */
104
105	/* Call the target and get an event */
106	ret = target_function();
107
108error_rmdir:
109	/* Cleanup temporary buildid dir */
110	rm_rf(__tempdir);
111error:
112	free(tempdir);
113	free(myself);
114	return ret;
115}
116#else
117static int test__sdt_event(struct test_suite *test __maybe_unused, int subtests __maybe_unused)
118{
119	pr_debug("Skip SDT event test because SDT support is not compiled\n");
120	return TEST_SKIP;
121}
122#endif
123
124DEFINE_SUITE("Probe SDT events", sdt_event);
125