xref: /linux/tools/perf/tests/dso-data.c (revision 2697b79a469b68e3ad3640f55284359c1396278d)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <dirent.h>
3 #include <stdlib.h>
4 #include <linux/kernel.h>
5 #include <linux/types.h>
6 #include <sys/stat.h>
7 #include <fcntl.h>
8 #include <string.h>
9 #include <sys/time.h>
10 #include <sys/resource.h>
11 #include <api/fs/fs.h>
12 #include "dso.h"
13 #include "dsos.h"
14 #include "machine.h"
15 #include "symbol.h"
16 #include "tests.h"
17 #include "debug.h"
18 
19 static char *test_file(int size)
20 {
21 #define TEMPL "/tmp/perf-test-XXXXXX"
22 	static char buf_templ[sizeof(TEMPL)];
23 	char *templ = buf_templ;
24 	int fd, i;
25 	unsigned char *buf;
26 
27 	strcpy(buf_templ, TEMPL);
28 #undef TEMPL
29 
30 	fd = mkstemp(templ);
31 	if (fd < 0) {
32 		perror("mkstemp failed");
33 		return NULL;
34 	}
35 
36 	buf = malloc(size);
37 	if (!buf) {
38 		close(fd);
39 		return NULL;
40 	}
41 
42 	for (i = 0; i < size; i++)
43 		buf[i] = (unsigned char) ((int) i % 10);
44 
45 	if (size != write(fd, buf, size))
46 		templ = NULL;
47 
48 	free(buf);
49 	close(fd);
50 	return templ;
51 }
52 
53 #define TEST_FILE_SIZE (DSO__DATA_CACHE_SIZE * 20)
54 
55 struct test_data_offset {
56 	off_t offset;
57 	u8 data[10];
58 	int size;
59 };
60 
61 struct test_data_offset offsets[] = {
62 	/* Fill first cache page. */
63 	{
64 		.offset = 10,
65 		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
66 		.size   = 10,
67 	},
68 	/* Read first cache page. */
69 	{
70 		.offset = 10,
71 		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
72 		.size   = 10,
73 	},
74 	/* Fill cache boundary pages. */
75 	{
76 		.offset = DSO__DATA_CACHE_SIZE - DSO__DATA_CACHE_SIZE % 10,
77 		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
78 		.size   = 10,
79 	},
80 	/* Read cache boundary pages. */
81 	{
82 		.offset = DSO__DATA_CACHE_SIZE - DSO__DATA_CACHE_SIZE % 10,
83 		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
84 		.size   = 10,
85 	},
86 	/* Fill final cache page. */
87 	{
88 		.offset = TEST_FILE_SIZE - 10,
89 		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
90 		.size   = 10,
91 	},
92 	/* Read final cache page. */
93 	{
94 		.offset = TEST_FILE_SIZE - 10,
95 		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
96 		.size   = 10,
97 	},
98 	/* Read final cache page. */
99 	{
100 		.offset = TEST_FILE_SIZE - 3,
101 		.data   = { 7, 8, 9, 0, 0, 0, 0, 0, 0, 0 },
102 		.size   = 3,
103 	},
104 };
105 
106 /* move it from util/dso.c for compatibility */
107 static int dso__data_fd(struct dso *dso, struct machine *machine)
108 {
109 	int fd = dso__data_get_fd(dso, machine);
110 
111 	if (fd >= 0)
112 		dso__data_put_fd(dso);
113 
114 	return fd;
115 }
116 
117 static int test__dso_data(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
118 {
119 	struct machine machine;
120 	struct dso *dso;
121 	char *file = test_file(TEST_FILE_SIZE);
122 	size_t i;
123 
124 	TEST_ASSERT_VAL("No test file", file);
125 
126 	memset(&machine, 0, sizeof(machine));
127 	dsos__init(&machine.dsos);
128 
129 	dso = dso__new(file);
130 	TEST_ASSERT_VAL("Failed to add dso", !dsos__add(&machine.dsos, dso));
131 	TEST_ASSERT_VAL("Failed to access to dso",
132 			dso__data_fd(dso, &machine) >= 0);
133 
134 	/* Basic 10 bytes tests. */
135 	for (i = 0; i < ARRAY_SIZE(offsets); i++) {
136 		struct test_data_offset *data = &offsets[i];
137 		ssize_t size;
138 		u8 buf[10];
139 
140 		memset(buf, 0, 10);
141 		size = dso__data_read_offset(dso, &machine, data->offset,
142 				     buf, 10);
143 
144 		TEST_ASSERT_VAL("Wrong size", size == data->size);
145 		TEST_ASSERT_VAL("Wrong data", !memcmp(buf, data->data, 10));
146 	}
147 
148 	/* Read cross multiple cache pages. */
149 	{
150 		ssize_t size;
151 		int c;
152 		u8 *buf;
153 
154 		buf = malloc(TEST_FILE_SIZE);
155 		TEST_ASSERT_VAL("ENOMEM\n", buf);
156 
157 		/* First iteration to fill caches, second one to read them. */
158 		for (c = 0; c < 2; c++) {
159 			memset(buf, 0, TEST_FILE_SIZE);
160 			size = dso__data_read_offset(dso, &machine, 10,
161 						     buf, TEST_FILE_SIZE);
162 
163 			TEST_ASSERT_VAL("Wrong size",
164 				size == (TEST_FILE_SIZE - 10));
165 
166 			for (i = 0; i < (size_t)size; i++)
167 				TEST_ASSERT_VAL("Wrong data",
168 					buf[i] == (i % 10));
169 		}
170 
171 		free(buf);
172 	}
173 
174 	dso__put(dso);
175 	dsos__exit(&machine.dsos);
176 	unlink(file);
177 	return 0;
178 }
179 
180 static long open_files_cnt(void)
181 {
182 	char path[PATH_MAX];
183 	struct dirent *dent;
184 	DIR *dir;
185 	long nr = 0;
186 
187 	scnprintf(path, PATH_MAX, "%s/self/fd", procfs__mountpoint());
188 	pr_debug("fd path: %s\n", path);
189 
190 	dir = opendir(path);
191 	TEST_ASSERT_VAL("failed to open fd directory", dir);
192 
193 	while ((dent = readdir(dir)) != NULL) {
194 		if (!strcmp(dent->d_name, ".") ||
195 		    !strcmp(dent->d_name, ".."))
196 			continue;
197 
198 		nr++;
199 	}
200 
201 	closedir(dir);
202 	return nr - 1;
203 }
204 
205 static int dsos__create(int cnt, int size, struct dsos *dsos)
206 {
207 	int i;
208 
209 	dsos__init(dsos);
210 
211 	for (i = 0; i < cnt; i++) {
212 		struct dso *dso;
213 		char *file = test_file(size);
214 
215 		TEST_ASSERT_VAL("failed to get dso file", file);
216 		dso = dso__new(file);
217 		TEST_ASSERT_VAL("failed to get dso", dso);
218 		TEST_ASSERT_VAL("failed to add dso", !dsos__add(dsos, dso));
219 		dso__put(dso);
220 	}
221 
222 	return 0;
223 }
224 
225 static void dsos__delete(struct dsos *dsos)
226 {
227 	for (unsigned int i = 0; i < dsos->cnt; i++) {
228 		struct dso *dso = dsos->dsos[i];
229 
230 		dso__data_close(dso);
231 		unlink(dso__name(dso));
232 	}
233 	dsos__exit(dsos);
234 }
235 
236 static int set_fd_limit(int n)
237 {
238 	struct rlimit rlim;
239 
240 	if (getrlimit(RLIMIT_NOFILE, &rlim))
241 		return -1;
242 
243 	pr_debug("file limit %ld, new %d\n", (long) rlim.rlim_cur, n);
244 
245 	rlim.rlim_cur = n;
246 	return setrlimit(RLIMIT_NOFILE, &rlim);
247 }
248 
249 static int test__dso_data_cache(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
250 {
251 	struct machine machine;
252 	long nr_end, nr = open_files_cnt();
253 	int dso_cnt, limit, i, fd;
254 
255 	/* Rest the internal dso open counter limit. */
256 	reset_fd_limit();
257 
258 	memset(&machine, 0, sizeof(machine));
259 
260 	/* set as system limit */
261 	limit = nr * 4;
262 	TEST_ASSERT_VAL("failed to set file limit", !set_fd_limit(limit));
263 
264 	/* and this is now our dso open FDs limit */
265 	dso_cnt = limit / 2;
266 	TEST_ASSERT_VAL("failed to create dsos\n",
267 			!dsos__create(dso_cnt, TEST_FILE_SIZE, &machine.dsos));
268 
269 	for (i = 0; i < (dso_cnt - 1); i++) {
270 		struct dso *dso = machine.dsos.dsos[i];
271 
272 		/*
273 		 * Open dsos via dso__data_fd(), it opens the data
274 		 * file and keep it open (unless open file limit).
275 		 */
276 		fd = dso__data_fd(dso, &machine);
277 		TEST_ASSERT_VAL("failed to get fd", fd > 0);
278 
279 		if (i % 2) {
280 			#define BUFSIZE 10
281 			u8 buf[BUFSIZE];
282 			ssize_t n;
283 
284 			n = dso__data_read_offset(dso, &machine, 0, buf, BUFSIZE);
285 			TEST_ASSERT_VAL("failed to read dso", n == BUFSIZE);
286 		}
287 	}
288 
289 	/* verify the first one is already open */
290 	TEST_ASSERT_VAL("dsos[0] is not open", dso__data(machine.dsos.dsos[0])->fd != -1);
291 
292 	/* open +1 dso to reach the allowed limit */
293 	fd = dso__data_fd(machine.dsos.dsos[i], &machine);
294 	TEST_ASSERT_VAL("failed to get fd", fd > 0);
295 
296 	/* should force the first one to be closed */
297 	TEST_ASSERT_VAL("failed to close dsos[0]", dso__data(machine.dsos.dsos[0])->fd == -1);
298 
299 	/* cleanup everything */
300 	dsos__delete(&machine.dsos);
301 
302 	/* Make sure we did not leak any file descriptor. */
303 	nr_end = open_files_cnt();
304 	pr_debug("nr start %ld, nr stop %ld\n", nr, nr_end);
305 	TEST_ASSERT_VAL("failed leaking files", nr == nr_end);
306 	return 0;
307 }
308 
309 static long new_limit(int count)
310 {
311 	int fd = open("/dev/null", O_RDONLY);
312 	long ret = fd;
313 	if (count > 0)
314 		ret = new_limit(--count);
315 	close(fd);
316 	return ret;
317 }
318 
319 static int test__dso_data_reopen(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
320 {
321 	struct machine machine;
322 	long nr_end, nr = open_files_cnt(), lim = new_limit(3);
323 	int fd, fd_extra;
324 
325 #define dso_0 (machine.dsos.dsos[0])
326 #define dso_1 (machine.dsos.dsos[1])
327 #define dso_2 (machine.dsos.dsos[2])
328 
329 	/* Rest the internal dso open counter limit. */
330 	reset_fd_limit();
331 
332 	memset(&machine, 0, sizeof(machine));
333 
334 	/*
335 	 * Test scenario:
336 	 * - create 3 dso objects
337 	 * - set process file descriptor limit to current
338 	 *   files count + 3
339 	 * - test that the first dso gets closed when we
340 	 *   reach the files count limit
341 	 */
342 
343 	/* Make sure we are able to open 3 fds anyway */
344 	TEST_ASSERT_VAL("failed to set file limit",
345 			!set_fd_limit((lim)));
346 
347 	TEST_ASSERT_VAL("failed to create dsos\n",
348 			!dsos__create(3, TEST_FILE_SIZE, &machine.dsos));
349 
350 	/* open dso_0 */
351 	fd = dso__data_fd(dso_0, &machine);
352 	TEST_ASSERT_VAL("failed to get fd", fd > 0);
353 
354 	/* open dso_1 */
355 	fd = dso__data_fd(dso_1, &machine);
356 	TEST_ASSERT_VAL("failed to get fd", fd > 0);
357 
358 	/*
359 	 * open extra file descriptor and we just
360 	 * reached the files count limit
361 	 */
362 	fd_extra = open("/dev/null", O_RDONLY);
363 	TEST_ASSERT_VAL("failed to open extra fd", fd_extra > 0);
364 
365 	/* open dso_2 */
366 	fd = dso__data_fd(dso_2, &machine);
367 	TEST_ASSERT_VAL("failed to get fd", fd > 0);
368 
369 	/*
370 	 * dso_0 should get closed, because we reached
371 	 * the file descriptor limit
372 	 */
373 	TEST_ASSERT_VAL("failed to close dso_0", dso__data(dso_0)->fd == -1);
374 
375 	/* open dso_0 */
376 	fd = dso__data_fd(dso_0, &machine);
377 	TEST_ASSERT_VAL("failed to get fd", fd > 0);
378 
379 	/*
380 	 * dso_1 should get closed, because we reached
381 	 * the file descriptor limit
382 	 */
383 	TEST_ASSERT_VAL("failed to close dso_1", dso__data(dso_1)->fd == -1);
384 
385 	/* cleanup everything */
386 	close(fd_extra);
387 	dsos__delete(&machine.dsos);
388 
389 	/* Make sure we did not leak any file descriptor. */
390 	nr_end = open_files_cnt();
391 	pr_debug("nr start %ld, nr stop %ld\n", nr, nr_end);
392 	TEST_ASSERT_VAL("failed leaking files", nr == nr_end);
393 	return 0;
394 }
395 
396 
397 static struct test_case tests__dso_data[] = {
398 	TEST_CASE("read", dso_data),
399 	TEST_CASE("cache", dso_data_cache),
400 	TEST_CASE("reopen", dso_data_reopen),
401 	{	.name = NULL, }
402 };
403 
404 struct test_suite suite__dso_data = {
405 	.desc = "DSO data tests",
406 	.test_cases = tests__dso_data,
407 };
408