summaryrefslogtreecommitdiff
path: root/tools/perf/tests/bpf.c
blob: fc102e4f403e2fa42b05647e247db576720b64fa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
// SPDX-License-Identifier: GPL-2.0
#include <errno.h>
#include <stdio.h>
#include <sys/epoll.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <util/record.h>
#include <util/util.h>
#include <util/bpf-loader.h>
#include <util/evlist.h>
#include <linux/bpf.h>
#include <linux/filter.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <api/fs/fs.h>
#include <bpf/bpf.h>
#include "tests.h"
#include "llvm.h"
#include "debug.h"
#include "parse-events.h"
#define NR_ITERS       111
#define PERF_TEST_BPF_PATH "/sys/fs/bpf/perf_test"

#ifdef HAVE_LIBBPF_SUPPORT

static int epoll_pwait_loop(void)
{
	int i;

	/* Should fail NR_ITERS times */
	for (i = 0; i < NR_ITERS; i++)
		epoll_pwait(-(i + 1), NULL, 0, 0, NULL);
	return 0;
}

#ifdef HAVE_BPF_PROLOGUE

static int llseek_loop(void)
{
	int fds[2], i;

	fds[0] = open("/dev/null", O_RDONLY);
	fds[1] = open("/dev/null", O_RDWR);

	if (fds[0] < 0 || fds[1] < 0)
		return -1;

	for (i = 0; i < NR_ITERS; i++) {
		lseek(fds[i % 2], i, (i / 2) % 2 ? SEEK_CUR : SEEK_SET);
		lseek(fds[(i + 1) % 2], i, (i / 2) % 2 ? SEEK_CUR : SEEK_SET);
	}
	close(fds[0]);
	close(fds[1]);
	return 0;
}

#endif

static struct {
	enum test_llvm__testcase prog_id;
	const char *desc;
	const char *name;
	const char *msg_compile_fail;
	const char *msg_load_fail;
	int (*target_func)(void);
	int expect_result;
	bool	pin;
} bpf_testcase_table[] = {
	{
		.prog_id	  = LLVM_TESTCASE_BASE,
		.desc		  = "Basic BPF filtering",
		.name		  = "[basic_bpf_test]",
		.msg_compile_fail = "fix 'perf test LLVM' first",
		.msg_load_fail	  = "load bpf object failed",
		.target_func	  = &epoll_pwait_loop,
		.expect_result	  = (NR_ITERS + 1) / 2,
	},
	{
		.prog_id	  = LLVM_TESTCASE_BASE,
		.desc		  = "BPF pinning",
		.name		  = "[bpf_pinning]",
		.msg_compile_fail = "fix kbuild first",
		.msg_load_fail	  = "check your vmlinux setting?",
		.target_func	  = &epoll_pwait_loop,
		.expect_result	  = (NR_ITERS + 1) / 2,
		.pin 		  = true,
	},
#ifdef HAVE_BPF_PROLOGUE
	{
		.prog_id	  = LLVM_TESTCASE_BPF_PROLOGUE,
		.desc		  = "BPF prologue generation",
		.name		  = "[bpf_prologue_test]",
		.msg_compile_fail = "fix kbuild first",
		.msg_load_fail	  = "check your vmlinux setting?",
		.target_func	  = &llseek_loop,
		.expect_result	  = (NR_ITERS + 1) / 4,
	},
#endif
	{
		.prog_id	  = LLVM_TESTCASE_BPF_RELOCATION,
		.desc		  = "BPF relocation checker",
		.name		  = "[bpf_relocation_test]",
		.msg_compile_fail = "fix 'perf test LLVM' first",
		.msg_load_fail	  = "libbpf error when dealing with relocation",
	},
};

static int do_test(struct bpf_object *obj, int (*func)(void),
		   int expect)
{
	struct record_opts opts = {
		.target = {
			.uid = UINT_MAX,
			.uses_mmap = true,
		},
		.freq	      = 0,
		.mmap_pages   = 256,
		.default_interval = 1,
	};

	char pid[16];
	char sbuf[STRERR_BUFSIZE];
	struct evlist *evlist;
	int i, ret = TEST_FAIL, err = 0, count = 0;

	struct parse_events_state parse_state;
	struct parse_events_error parse_error;

	bzero(&parse_error, sizeof(parse_error));
	bzero(&parse_state, sizeof(parse_state));
	parse_state.error = &parse_error;
	INIT_LIST_HEAD(&parse_state.list);

	err = parse_events_load_bpf_obj(&parse_state, &parse_state.list, obj, NULL);
	if (err || list_empty(&parse_state.list)) {
		pr_debug("Failed to add events selected by BPF\n");
		return TEST_FAIL;
	}

	snprintf(pid, sizeof(pid), "%d", getpid());
	pid[sizeof(pid) - 1] = '\0';
	opts.target.tid = opts.target.pid = pid;

	/* Instead of perf_evlist__new_default, don't add default events */
	evlist = evlist__new();
	if (!evlist) {
		pr_debug("Not enough memory to create evlist\n");
		return TEST_FAIL;
	}

	err = perf_evlist__create_maps(evlist, &opts.target);
	if (err < 0) {
		pr_debug("Not enough memory to create thread/cpu maps\n");
		goto out_delete_evlist;
	}

	perf_evlist__splice_list_tail(evlist, &parse_state.list);
	evlist->nr_groups = parse_state.nr_groups;

	perf_evlist__config(evlist, &opts, NULL);

	err = evlist__open(evlist);
	if (err < 0) {
		pr_debug("perf_evlist__open: %s\n",
			 str_error_r(errno, sbuf, sizeof(sbuf)));
		goto out_delete_evlist;
	}

	err = perf_evlist__mmap(evlist, opts.mmap_pages);
	if (err < 0) {
		pr_debug("perf_evlist__mmap: %s\n",
			 str_error_r(errno, sbuf, sizeof(sbuf)));
		goto out_delete_evlist;
	}

	evlist__enable(evlist);
	(*func)();
	evlist__disable(evlist);

	for (i = 0; i < evlist->nr_mmaps; i++) {
		union perf_event *event;
		struct perf_mmap *md;

		md = &evlist->mmap[i];
		if (perf_mmap__read_init(md) < 0)
			continue;

		while ((event = perf_mmap__read_event(md)) != NULL) {
			const u32 type = event->header.type;

			if (type == PERF_RECORD_SAMPLE)
				count ++;
		}
		perf_mmap__read_done(md);
	}

	if (count != expect) {
		pr_debug("BPF filter result incorrect, expected %d, got %d samples\n", expect, count);
		goto out_delete_evlist;
	}

	ret = TEST_OK;

out_delete_evlist:
	evlist__delete(evlist);
	return ret;
}

static struct bpf_object *
prepare_bpf(void *obj_buf, size_t obj_buf_sz, const char *name)
{
	struct bpf_object *obj;

	obj = bpf__prepare_load_buffer(obj_buf, obj_buf_sz, name);
	if (IS_ERR(obj)) {
		pr_debug("Compile BPF program failed.\n");
		return NULL;
	}
	return obj;
}

static int __test__bpf(int idx)
{
	int ret;
	void *obj_buf;
	size_t obj_buf_sz;
	struct bpf_object *obj;

	ret = test_llvm__fetch_bpf_obj(&obj_buf, &obj_buf_sz,
				       bpf_testcase_table[idx].prog_id,
				       true, NULL);
	if (ret != TEST_OK || !obj_buf || !obj_buf_sz) {
		pr_debug("Unable to get BPF object, %s\n",
			 bpf_testcase_table[idx].msg_compile_fail);
		if (idx == 0)
			return TEST_SKIP;
		else
			return TEST_FAIL;
	}

	obj = prepare_bpf(obj_buf, obj_buf_sz,
			  bpf_testcase_table[idx].name);
	if ((!!bpf_testcase_table[idx].target_func) != (!!obj)) {
		if (!obj)
			pr_debug("Fail to load BPF object: %s\n",
				 bpf_testcase_table[idx].msg_load_fail);
		else
			pr_debug("Success unexpectedly: %s\n",
				 bpf_testcase_table[idx].msg_load_fail);
		ret = TEST_FAIL;
		goto out;
	}

	if (obj) {
		ret = do_test(obj,
			      bpf_testcase_table[idx].target_func,
			      bpf_testcase_table[idx].expect_result);
		if (ret != TEST_OK)
			goto out;
		if (bpf_testcase_table[idx].pin) {
			int err;

			if (!bpf_fs__mount()) {
				pr_debug("BPF filesystem not mounted\n");
				ret = TEST_FAIL;
				goto out;
			}
			err = mkdir(PERF_TEST_BPF_PATH, 0777);
			if (err && errno != EEXIST) {
				pr_debug("Failed to make perf_test dir: %s\n",
					 strerror(errno));
				ret = TEST_FAIL;
				goto out;
			}
			if (bpf_object__pin(obj, PERF_TEST_BPF_PATH))
				ret = TEST_FAIL;
			if (rm_rf(PERF_TEST_BPF_PATH))
				ret = TEST_FAIL;
		}
	}

out:
	bpf__clear();
	return ret;
}

int test__bpf_subtest_get_nr(void)
{
	return (int)ARRAY_SIZE(bpf_testcase_table);
}

const char *test__bpf_subtest_get_desc(int i)
{
	if (i < 0 || i >= (int)ARRAY_SIZE(bpf_testcase_table))
		return NULL;
	return bpf_testcase_table[i].desc;
}

static int check_env(void)
{
	int err;
	unsigned int kver_int;
	char license[] = "GPL";

	struct bpf_insn insns[] = {
		BPF_MOV64_IMM(BPF_REG_0, 1),
		BPF_EXIT_INSN(),
	};

	err = fetch_kernel_version(&kver_int, NULL, 0);
	if (err) {
		pr_debug("Unable to get kernel version\n");
		return err;
	}

	err = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns,
			       sizeof(insns) / sizeof(insns[0]),
			       license, kver_int, NULL, 0);
	if (err < 0) {
		pr_err("Missing basic BPF support, skip this test: %s\n",
		       strerror(errno));
		return err;
	}
	close(err);

	return 0;
}

int test__bpf(struct test *test __maybe_unused, int i)
{
	int err;

	if (i < 0 || i >= (int)ARRAY_SIZE(bpf_testcase_table))
		return TEST_FAIL;

	if (geteuid() != 0) {
		pr_debug("Only root can run BPF test\n");
		return TEST_SKIP;
	}

	if (check_env())
		return TEST_SKIP;

	err = __test__bpf(i);
	return err;
}

#else
int test__bpf_subtest_get_nr(void)
{
	return 0;
}

const char *test__bpf_subtest_get_desc(int i __maybe_unused)
{
	return NULL;
}

int test__bpf(struct test *test __maybe_unused, int i __maybe_unused)
{
	pr_debug("Skip BPF test because BPF support is not compiled\n");
	return TEST_SKIP;
}
#endif