xref: /linux/tools/perf/tests/dso-data.c (revision 63307d015b91e626c97bb82e88054af3d0b74643)
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 "util.h"
13 #include "machine.h"
14 #include "symbol.h"
15 #include "tests.h"
16 #include "debug.h"
17 
18 static char *test_file(int size)
19 {
20 #define TEMPL "/tmp/perf-test-XXXXXX"
21 	static char buf_templ[sizeof(TEMPL)];
22 	char *templ = buf_templ;
23 	int fd, i;
24 	unsigned char *buf;
25 
26 	strcpy(buf_templ, TEMPL);
27 #undef TEMPL
28 
29 	fd = mkstemp(templ);
30 	if (fd < 0) {
31 		perror("mkstemp failed");
32 		return NULL;
33 	}
34 
35 	buf = malloc(size);
36 	if (!buf) {
37 		close(fd);
38 		return NULL;
39 	}
40 
41 	for (i = 0; i < size; i++)
42 		buf[i] = (unsigned char) ((int) i % 10);
43 
44 	if (size != write(fd, buf, size))
45 		templ = NULL;
46 
47 	free(buf);
48 	close(fd);
49 	return templ;
50 }
51 
52 #define TEST_FILE_SIZE (DSO__DATA_CACHE_SIZE * 20)
53 
54 struct test_data_offset {
55 	off_t offset;
56 	u8 data[10];
57 	int size;
58 };
59 
60 struct test_data_offset offsets[] = {
61 	/* Fill first cache page. */
62 	{
63 		.offset = 10,
64 		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
65 		.size   = 10,
66 	},
67 	/* Read first cache page. */
68 	{
69 		.offset = 10,
70 		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
71 		.size   = 10,
72 	},
73 	/* Fill cache boundary pages. */
74 	{
75 		.offset = DSO__DATA_CACHE_SIZE - DSO__DATA_CACHE_SIZE % 10,
76 		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
77 		.size   = 10,
78 	},
79 	/* Read cache boundary pages. */
80 	{
81 		.offset = DSO__DATA_CACHE_SIZE - DSO__DATA_CACHE_SIZE % 10,
82 		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
83 		.size   = 10,
84 	},
85 	/* Fill final cache page. */
86 	{
87 		.offset = TEST_FILE_SIZE - 10,
88 		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
89 		.size   = 10,
90 	},
91 	/* Read final cache page. */
92 	{
93 		.offset = TEST_FILE_SIZE - 10,
94 		.data   = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 },
95 		.size   = 10,
96 	},
97 	/* Read final cache page. */
98 	{
99 		.offset = TEST_FILE_SIZE - 3,
100 		.data   = { 7, 8, 9, 0, 0, 0, 0, 0, 0, 0 },
101 		.size   = 3,
102 	},
103 };
104 
105 /* move it from util/dso.c for compatibility */
106 static int dso__data_fd(struct dso *dso, struct machine *machine)
107 {
108 	int fd = dso__data_get_fd(dso, machine);
109 
110 	if (fd >= 0)
111 		dso__data_put_fd(dso);
112 
113 	return fd;
114 }
115 
116 int test__dso_data(struct test *test __maybe_unused, int subtest __maybe_unused)
117 {
118 	struct machine machine;
119 	struct dso *dso;
120 	char *file = test_file(TEST_FILE_SIZE);
121 	size_t i;
122 
123 	TEST_ASSERT_VAL("No test file", file);
124 
125 	memset(&machine, 0, sizeof(machine));
126 
127 	dso = dso__new((const char *)file);
128 
129 	TEST_ASSERT_VAL("Failed to access to dso",
130 			dso__data_fd(dso, &machine) >= 0);
131 
132 	/* Basic 10 bytes tests. */
133 	for (i = 0; i < ARRAY_SIZE(offsets); i++) {
134 		struct test_data_offset *data = &offsets[i];
135 		ssize_t size;
136 		u8 buf[10];
137 
138 		memset(buf, 0, 10);
139 		size = dso__data_read_offset(dso, &machine, data->offset,
140 				     buf, 10);
141 
142 		TEST_ASSERT_VAL("Wrong size", size == data->size);
143 		TEST_ASSERT_VAL("Wrong data", !memcmp(buf, data->data, 10));
144 	}
145 
146 	/* Read cross multiple cache pages. */
147 	{
148 		ssize_t size;
149 		int c;
150 		u8 *buf;
151 
152 		buf = malloc(TEST_FILE_SIZE);
153 		TEST_ASSERT_VAL("ENOMEM\n", buf);
154 
155 		/* First iteration to fill caches, second one to read them. */
156 		for (c = 0; c < 2; c++) {
157 			memset(buf, 0, TEST_FILE_SIZE);
158 			size = dso__data_read_offset(dso, &machine, 10,
159 						     buf, TEST_FILE_SIZE);
160 
161 			TEST_ASSERT_VAL("Wrong size",
162 				size == (TEST_FILE_SIZE - 10));
163 
164 			for (i = 0; i < (size_t)size; i++)
165 				TEST_ASSERT_VAL("Wrong data",
166 					buf[i] == (i % 10));
167 		}
168 
169 		free(buf);
170 	}
171 
172 	dso__put(dso);
173 	unlink(file);
174 	return 0;
175 }
176 
177 static long open_files_cnt(void)
178 {
179 	char path[PATH_MAX];
180 	struct dirent *dent;
181 	DIR *dir;
182 	long nr = 0;
183 
184 	scnprintf(path, PATH_MAX, "%s/self/fd", procfs__mountpoint());
185 	pr_debug("fd path: %s\n", path);
186 
187 	dir = opendir(path);
188 	TEST_ASSERT_VAL("failed to open fd directory", dir);
189 
190 	while ((dent = readdir(dir)) != NULL) {
191 		if (!strcmp(dent->d_name, ".") ||
192 		    !strcmp(dent->d_name, ".."))
193 			continue;
194 
195 		nr++;
196 	}
197 
198 	closedir(dir);
199 	return nr - 1;
200 }
201 
202 static struct dso **dsos;
203 
204 static int dsos__create(int cnt, int size)
205 {
206 	int i;
207 
208 	dsos = malloc(sizeof(*dsos) * cnt);
209 	TEST_ASSERT_VAL("failed to alloc dsos array", dsos);
210 
211 	for (i = 0; i < cnt; i++) {
212 		char *file;
213 
214 		file = test_file(size);
215 		TEST_ASSERT_VAL("failed to get dso file", file);
216 
217 		dsos[i] = dso__new(file);
218 		TEST_ASSERT_VAL("failed to get dso", dsos[i]);
219 	}
220 
221 	return 0;
222 }
223 
224 static void dsos__delete(int cnt)
225 {
226 	int i;
227 
228 	for (i = 0; i < cnt; i++) {
229 		struct dso *dso = dsos[i];
230 
231 		unlink(dso->name);
232 		dso__put(dso);
233 	}
234 
235 	free(dsos);
236 }
237 
238 static int set_fd_limit(int n)
239 {
240 	struct rlimit rlim;
241 
242 	if (getrlimit(RLIMIT_NOFILE, &rlim))
243 		return -1;
244 
245 	pr_debug("file limit %ld, new %d\n", (long) rlim.rlim_cur, n);
246 
247 	rlim.rlim_cur = n;
248 	return setrlimit(RLIMIT_NOFILE, &rlim);
249 }
250 
251 int test__dso_data_cache(struct test *test __maybe_unused, int subtest __maybe_unused)
252 {
253 	struct machine machine;
254 	long nr_end, nr = open_files_cnt();
255 	int dso_cnt, limit, i, fd;
256 
257 	/* Rest the internal dso open counter limit. */
258 	reset_fd_limit();
259 
260 	memset(&machine, 0, sizeof(machine));
261 
262 	/* set as system limit */
263 	limit = nr * 4;
264 	TEST_ASSERT_VAL("failed to set file limit", !set_fd_limit(limit));
265 
266 	/* and this is now our dso open FDs limit */
267 	dso_cnt = limit / 2;
268 	TEST_ASSERT_VAL("failed to create dsos\n",
269 		!dsos__create(dso_cnt, TEST_FILE_SIZE));
270 
271 	for (i = 0; i < (dso_cnt - 1); i++) {
272 		struct dso *dso = dsos[i];
273 
274 		/*
275 		 * Open dsos via dso__data_fd(), it opens the data
276 		 * file and keep it open (unless open file limit).
277 		 */
278 		fd = dso__data_fd(dso, &machine);
279 		TEST_ASSERT_VAL("failed to get fd", fd > 0);
280 
281 		if (i % 2) {
282 			#define BUFSIZE 10
283 			u8 buf[BUFSIZE];
284 			ssize_t n;
285 
286 			n = dso__data_read_offset(dso, &machine, 0, buf, BUFSIZE);
287 			TEST_ASSERT_VAL("failed to read dso", n == BUFSIZE);
288 		}
289 	}
290 
291 	/* verify the first one is already open */
292 	TEST_ASSERT_VAL("dsos[0] is not open", dsos[0]->data.fd != -1);
293 
294 	/* open +1 dso to reach the allowed limit */
295 	fd = dso__data_fd(dsos[i], &machine);
296 	TEST_ASSERT_VAL("failed to get fd", fd > 0);
297 
298 	/* should force the first one to be closed */
299 	TEST_ASSERT_VAL("failed to close dsos[0]", dsos[0]->data.fd == -1);
300 
301 	/* cleanup everything */
302 	dsos__delete(dso_cnt);
303 
304 	/* Make sure we did not leak any file descriptor. */
305 	nr_end = open_files_cnt();
306 	pr_debug("nr start %ld, nr stop %ld\n", nr, nr_end);
307 	TEST_ASSERT_VAL("failed leaking files", nr == nr_end);
308 	return 0;
309 }
310 
311 int test__dso_data_reopen(struct test *test __maybe_unused, int subtest __maybe_unused)
312 {
313 	struct machine machine;
314 	long nr_end, nr = open_files_cnt();
315 	int fd, fd_extra;
316 
317 #define dso_0 (dsos[0])
318 #define dso_1 (dsos[1])
319 #define dso_2 (dsos[2])
320 
321 	/* Rest the internal dso open counter limit. */
322 	reset_fd_limit();
323 
324 	memset(&machine, 0, sizeof(machine));
325 
326 	/*
327 	 * Test scenario:
328 	 * - create 3 dso objects
329 	 * - set process file descriptor limit to current
330 	 *   files count + 3
331 	 * - test that the first dso gets closed when we
332 	 *   reach the files count limit
333 	 */
334 
335 	/* Make sure we are able to open 3 fds anyway */
336 	TEST_ASSERT_VAL("failed to set file limit",
337 			!set_fd_limit((nr + 3)));
338 
339 	TEST_ASSERT_VAL("failed to create dsos\n", !dsos__create(3, TEST_FILE_SIZE));
340 
341 	/* open dso_0 */
342 	fd = dso__data_fd(dso_0, &machine);
343 	TEST_ASSERT_VAL("failed to get fd", fd > 0);
344 
345 	/* open dso_1 */
346 	fd = dso__data_fd(dso_1, &machine);
347 	TEST_ASSERT_VAL("failed to get fd", fd > 0);
348 
349 	/*
350 	 * open extra file descriptor and we just
351 	 * reached the files count limit
352 	 */
353 	fd_extra = open("/dev/null", O_RDONLY);
354 	TEST_ASSERT_VAL("failed to open extra fd", fd_extra > 0);
355 
356 	/* open dso_2 */
357 	fd = dso__data_fd(dso_2, &machine);
358 	TEST_ASSERT_VAL("failed to get fd", fd > 0);
359 
360 	/*
361 	 * dso_0 should get closed, because we reached
362 	 * the file descriptor limit
363 	 */
364 	TEST_ASSERT_VAL("failed to close dso_0", dso_0->data.fd == -1);
365 
366 	/* open dso_0 */
367 	fd = dso__data_fd(dso_0, &machine);
368 	TEST_ASSERT_VAL("failed to get fd", fd > 0);
369 
370 	/*
371 	 * dso_1 should get closed, because we reached
372 	 * the file descriptor limit
373 	 */
374 	TEST_ASSERT_VAL("failed to close dso_1", dso_1->data.fd == -1);
375 
376 	/* cleanup everything */
377 	close(fd_extra);
378 	dsos__delete(3);
379 
380 	/* Make sure we did not leak any file descriptor. */
381 	nr_end = open_files_cnt();
382 	pr_debug("nr start %ld, nr stop %ld\n", nr, nr_end);
383 	TEST_ASSERT_VAL("failed leaking files", nr == nr_end);
384 	return 0;
385 }
386