xref: /openbmc/linux/tools/perf/util/util.c (revision d3597236)
1 #include "../perf.h"
2 #include "util.h"
3 #include "debug.h"
4 #include <api/fs/fs.h>
5 #include <sys/mman.h>
6 #ifdef HAVE_BACKTRACE_SUPPORT
7 #include <execinfo.h>
8 #endif
9 #include <stdio.h>
10 #include <stdlib.h>
11 #include <string.h>
12 #include <errno.h>
13 #include <limits.h>
14 #include <byteswap.h>
15 #include <linux/kernel.h>
16 #include <unistd.h>
17 #include "callchain.h"
18 
19 struct callchain_param	callchain_param = {
20 	.mode	= CHAIN_GRAPH_REL,
21 	.min_percent = 0.5,
22 	.order  = ORDER_CALLEE,
23 	.key	= CCKEY_FUNCTION
24 };
25 
26 /*
27  * XXX We need to find a better place for these things...
28  */
29 unsigned int page_size;
30 int cacheline_size;
31 
32 bool test_attr__enabled;
33 
34 bool perf_host  = true;
35 bool perf_guest = false;
36 
37 char tracing_events_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing/events";
38 
39 void event_attr_init(struct perf_event_attr *attr)
40 {
41 	if (!perf_host)
42 		attr->exclude_host  = 1;
43 	if (!perf_guest)
44 		attr->exclude_guest = 1;
45 	/* to capture ABI version */
46 	attr->size = sizeof(*attr);
47 }
48 
49 int mkdir_p(char *path, mode_t mode)
50 {
51 	struct stat st;
52 	int err;
53 	char *d = path;
54 
55 	if (*d != '/')
56 		return -1;
57 
58 	if (stat(path, &st) == 0)
59 		return 0;
60 
61 	while (*++d == '/');
62 
63 	while ((d = strchr(d, '/'))) {
64 		*d = '\0';
65 		err = stat(path, &st) && mkdir(path, mode);
66 		*d++ = '/';
67 		if (err)
68 			return -1;
69 		while (*d == '/')
70 			++d;
71 	}
72 	return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
73 }
74 
75 int rm_rf(char *path)
76 {
77 	DIR *dir;
78 	int ret = 0;
79 	struct dirent *d;
80 	char namebuf[PATH_MAX];
81 
82 	dir = opendir(path);
83 	if (dir == NULL)
84 		return 0;
85 
86 	while ((d = readdir(dir)) != NULL && !ret) {
87 		struct stat statbuf;
88 
89 		if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
90 			continue;
91 
92 		scnprintf(namebuf, sizeof(namebuf), "%s/%s",
93 			  path, d->d_name);
94 
95 		ret = stat(namebuf, &statbuf);
96 		if (ret < 0) {
97 			pr_debug("stat failed: %s\n", namebuf);
98 			break;
99 		}
100 
101 		if (S_ISREG(statbuf.st_mode))
102 			ret = unlink(namebuf);
103 		else if (S_ISDIR(statbuf.st_mode))
104 			ret = rm_rf(namebuf);
105 		else {
106 			pr_debug("unknown file: %s\n", namebuf);
107 			ret = -1;
108 		}
109 	}
110 	closedir(dir);
111 
112 	if (ret < 0)
113 		return ret;
114 
115 	return rmdir(path);
116 }
117 
118 static int slow_copyfile(const char *from, const char *to)
119 {
120 	int err = -1;
121 	char *line = NULL;
122 	size_t n;
123 	FILE *from_fp = fopen(from, "r"), *to_fp;
124 
125 	if (from_fp == NULL)
126 		goto out;
127 
128 	to_fp = fopen(to, "w");
129 	if (to_fp == NULL)
130 		goto out_fclose_from;
131 
132 	while (getline(&line, &n, from_fp) > 0)
133 		if (fputs(line, to_fp) == EOF)
134 			goto out_fclose_to;
135 	err = 0;
136 out_fclose_to:
137 	fclose(to_fp);
138 	free(line);
139 out_fclose_from:
140 	fclose(from_fp);
141 out:
142 	return err;
143 }
144 
145 int copyfile_offset(int ifd, loff_t off_in, int ofd, loff_t off_out, u64 size)
146 {
147 	void *ptr;
148 	loff_t pgoff;
149 
150 	pgoff = off_in & ~(page_size - 1);
151 	off_in -= pgoff;
152 
153 	ptr = mmap(NULL, off_in + size, PROT_READ, MAP_PRIVATE, ifd, pgoff);
154 	if (ptr == MAP_FAILED)
155 		return -1;
156 
157 	while (size) {
158 		ssize_t ret = pwrite(ofd, ptr + off_in, size, off_out);
159 		if (ret < 0 && errno == EINTR)
160 			continue;
161 		if (ret <= 0)
162 			break;
163 
164 		size -= ret;
165 		off_in += ret;
166 		off_out -= ret;
167 	}
168 	munmap(ptr, off_in + size);
169 
170 	return size ? -1 : 0;
171 }
172 
173 int copyfile_mode(const char *from, const char *to, mode_t mode)
174 {
175 	int fromfd, tofd;
176 	struct stat st;
177 	int err = -1;
178 	char *tmp = NULL, *ptr = NULL;
179 
180 	if (stat(from, &st))
181 		goto out;
182 
183 	/* extra 'x' at the end is to reserve space for '.' */
184 	if (asprintf(&tmp, "%s.XXXXXXx", to) < 0) {
185 		tmp = NULL;
186 		goto out;
187 	}
188 	ptr = strrchr(tmp, '/');
189 	if (!ptr)
190 		goto out;
191 	ptr = memmove(ptr + 1, ptr, strlen(ptr) - 1);
192 	*ptr = '.';
193 
194 	tofd = mkstemp(tmp);
195 	if (tofd < 0)
196 		goto out;
197 
198 	if (fchmod(tofd, mode))
199 		goto out_close_to;
200 
201 	if (st.st_size == 0) { /* /proc? do it slowly... */
202 		err = slow_copyfile(from, tmp);
203 		goto out_close_to;
204 	}
205 
206 	fromfd = open(from, O_RDONLY);
207 	if (fromfd < 0)
208 		goto out_close_to;
209 
210 	err = copyfile_offset(fromfd, 0, tofd, 0, st.st_size);
211 
212 	close(fromfd);
213 out_close_to:
214 	close(tofd);
215 	if (!err)
216 		err = link(tmp, to);
217 	unlink(tmp);
218 out:
219 	free(tmp);
220 	return err;
221 }
222 
223 int copyfile(const char *from, const char *to)
224 {
225 	return copyfile_mode(from, to, 0755);
226 }
227 
228 unsigned long convert_unit(unsigned long value, char *unit)
229 {
230 	*unit = ' ';
231 
232 	if (value > 1000) {
233 		value /= 1000;
234 		*unit = 'K';
235 	}
236 
237 	if (value > 1000) {
238 		value /= 1000;
239 		*unit = 'M';
240 	}
241 
242 	if (value > 1000) {
243 		value /= 1000;
244 		*unit = 'G';
245 	}
246 
247 	return value;
248 }
249 
250 static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
251 {
252 	void *buf_start = buf;
253 	size_t left = n;
254 
255 	while (left) {
256 		ssize_t ret = is_read ? read(fd, buf, left) :
257 					write(fd, buf, left);
258 
259 		if (ret < 0 && errno == EINTR)
260 			continue;
261 		if (ret <= 0)
262 			return ret;
263 
264 		left -= ret;
265 		buf  += ret;
266 	}
267 
268 	BUG_ON((size_t)(buf - buf_start) != n);
269 	return n;
270 }
271 
272 /*
273  * Read exactly 'n' bytes or return an error.
274  */
275 ssize_t readn(int fd, void *buf, size_t n)
276 {
277 	return ion(true, fd, buf, n);
278 }
279 
280 /*
281  * Write exactly 'n' bytes or return an error.
282  */
283 ssize_t writen(int fd, void *buf, size_t n)
284 {
285 	return ion(false, fd, buf, n);
286 }
287 
288 size_t hex_width(u64 v)
289 {
290 	size_t n = 1;
291 
292 	while ((v >>= 4))
293 		++n;
294 
295 	return n;
296 }
297 
298 static int hex(char ch)
299 {
300 	if ((ch >= '0') && (ch <= '9'))
301 		return ch - '0';
302 	if ((ch >= 'a') && (ch <= 'f'))
303 		return ch - 'a' + 10;
304 	if ((ch >= 'A') && (ch <= 'F'))
305 		return ch - 'A' + 10;
306 	return -1;
307 }
308 
309 /*
310  * While we find nice hex chars, build a long_val.
311  * Return number of chars processed.
312  */
313 int hex2u64(const char *ptr, u64 *long_val)
314 {
315 	const char *p = ptr;
316 	*long_val = 0;
317 
318 	while (*p) {
319 		const int hex_val = hex(*p);
320 
321 		if (hex_val < 0)
322 			break;
323 
324 		*long_val = (*long_val << 4) | hex_val;
325 		p++;
326 	}
327 
328 	return p - ptr;
329 }
330 
331 /* Obtain a backtrace and print it to stdout. */
332 #ifdef HAVE_BACKTRACE_SUPPORT
333 void dump_stack(void)
334 {
335 	void *array[16];
336 	size_t size = backtrace(array, ARRAY_SIZE(array));
337 	char **strings = backtrace_symbols(array, size);
338 	size_t i;
339 
340 	printf("Obtained %zd stack frames.\n", size);
341 
342 	for (i = 0; i < size; i++)
343 		printf("%s\n", strings[i]);
344 
345 	free(strings);
346 }
347 #else
348 void dump_stack(void) {}
349 #endif
350 
351 void sighandler_dump_stack(int sig)
352 {
353 	psignal(sig, "perf");
354 	dump_stack();
355 	exit(sig);
356 }
357 
358 void get_term_dimensions(struct winsize *ws)
359 {
360 	char *s = getenv("LINES");
361 
362 	if (s != NULL) {
363 		ws->ws_row = atoi(s);
364 		s = getenv("COLUMNS");
365 		if (s != NULL) {
366 			ws->ws_col = atoi(s);
367 			if (ws->ws_row && ws->ws_col)
368 				return;
369 		}
370 	}
371 #ifdef TIOCGWINSZ
372 	if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
373 	    ws->ws_row && ws->ws_col)
374 		return;
375 #endif
376 	ws->ws_row = 25;
377 	ws->ws_col = 80;
378 }
379 
380 void set_term_quiet_input(struct termios *old)
381 {
382 	struct termios tc;
383 
384 	tcgetattr(0, old);
385 	tc = *old;
386 	tc.c_lflag &= ~(ICANON | ECHO);
387 	tc.c_cc[VMIN] = 0;
388 	tc.c_cc[VTIME] = 0;
389 	tcsetattr(0, TCSANOW, &tc);
390 }
391 
392 static void set_tracing_events_path(const char *tracing, const char *mountpoint)
393 {
394 	snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s%s",
395 		 mountpoint, tracing, "events");
396 }
397 
398 static const char *__perf_tracefs_mount(const char *mountpoint)
399 {
400 	const char *mnt;
401 
402 	mnt = tracefs_mount(mountpoint);
403 	if (!mnt)
404 		return NULL;
405 
406 	set_tracing_events_path("", mnt);
407 
408 	return mnt;
409 }
410 
411 static const char *__perf_debugfs_mount(const char *mountpoint)
412 {
413 	const char *mnt;
414 
415 	mnt = debugfs_mount(mountpoint);
416 	if (!mnt)
417 		return NULL;
418 
419 	set_tracing_events_path("tracing/", mnt);
420 
421 	return mnt;
422 }
423 
424 const char *perf_debugfs_mount(const char *mountpoint)
425 {
426 	const char *mnt;
427 
428 	mnt = __perf_tracefs_mount(mountpoint);
429 	if (mnt)
430 		return mnt;
431 
432 	mnt = __perf_debugfs_mount(mountpoint);
433 
434 	return mnt;
435 }
436 
437 void perf_debugfs_set_path(const char *mntpt)
438 {
439 	snprintf(debugfs_mountpoint, strlen(debugfs_mountpoint), "%s", mntpt);
440 	set_tracing_events_path("tracing/", mntpt);
441 }
442 
443 static const char *find_tracefs(void)
444 {
445 	const char *path = __perf_tracefs_mount(NULL);
446 
447 	return path;
448 }
449 
450 static const char *find_debugfs(void)
451 {
452 	const char *path = __perf_debugfs_mount(NULL);
453 
454 	if (!path)
455 		fprintf(stderr, "Your kernel does not support the debugfs filesystem");
456 
457 	return path;
458 }
459 
460 /*
461  * Finds the path to the debugfs/tracing
462  * Allocates the string and stores it.
463  */
464 const char *find_tracing_dir(void)
465 {
466 	const char *tracing_dir = "";
467 	static char *tracing;
468 	static int tracing_found;
469 	const char *debugfs;
470 
471 	if (tracing_found)
472 		return tracing;
473 
474 	debugfs = find_tracefs();
475 	if (!debugfs) {
476 		tracing_dir = "/tracing";
477 		debugfs = find_debugfs();
478 		if (!debugfs)
479 			return NULL;
480 	}
481 
482 	if (asprintf(&tracing, "%s%s", debugfs, tracing_dir) < 0)
483 		return NULL;
484 
485 	tracing_found = 1;
486 	return tracing;
487 }
488 
489 char *get_tracing_file(const char *name)
490 {
491 	const char *tracing;
492 	char *file;
493 
494 	tracing = find_tracing_dir();
495 	if (!tracing)
496 		return NULL;
497 
498 	if (asprintf(&file, "%s/%s", tracing, name) < 0)
499 		return NULL;
500 
501 	return file;
502 }
503 
504 void put_tracing_file(char *file)
505 {
506 	free(file);
507 }
508 
509 int parse_nsec_time(const char *str, u64 *ptime)
510 {
511 	u64 time_sec, time_nsec;
512 	char *end;
513 
514 	time_sec = strtoul(str, &end, 10);
515 	if (*end != '.' && *end != '\0')
516 		return -1;
517 
518 	if (*end == '.') {
519 		int i;
520 		char nsec_buf[10];
521 
522 		if (strlen(++end) > 9)
523 			return -1;
524 
525 		strncpy(nsec_buf, end, 9);
526 		nsec_buf[9] = '\0';
527 
528 		/* make it nsec precision */
529 		for (i = strlen(nsec_buf); i < 9; i++)
530 			nsec_buf[i] = '0';
531 
532 		time_nsec = strtoul(nsec_buf, &end, 10);
533 		if (*end != '\0')
534 			return -1;
535 	} else
536 		time_nsec = 0;
537 
538 	*ptime = time_sec * NSEC_PER_SEC + time_nsec;
539 	return 0;
540 }
541 
542 unsigned long parse_tag_value(const char *str, struct parse_tag *tags)
543 {
544 	struct parse_tag *i = tags;
545 
546 	while (i->tag) {
547 		char *s;
548 
549 		s = strchr(str, i->tag);
550 		if (s) {
551 			unsigned long int value;
552 			char *endptr;
553 
554 			value = strtoul(str, &endptr, 10);
555 			if (s != endptr)
556 				break;
557 
558 			if (value > ULONG_MAX / i->mult)
559 				break;
560 			value *= i->mult;
561 			return value;
562 		}
563 		i++;
564 	}
565 
566 	return (unsigned long) -1;
567 }
568 
569 int filename__read_str(const char *filename, char **buf, size_t *sizep)
570 {
571 	size_t size = 0, alloc_size = 0;
572 	void *bf = NULL, *nbf;
573 	int fd, n, err = 0;
574 	char sbuf[STRERR_BUFSIZE];
575 
576 	fd = open(filename, O_RDONLY);
577 	if (fd < 0)
578 		return -errno;
579 
580 	do {
581 		if (size == alloc_size) {
582 			alloc_size += BUFSIZ;
583 			nbf = realloc(bf, alloc_size);
584 			if (!nbf) {
585 				err = -ENOMEM;
586 				break;
587 			}
588 
589 			bf = nbf;
590 		}
591 
592 		n = read(fd, bf + size, alloc_size - size);
593 		if (n < 0) {
594 			if (size) {
595 				pr_warning("read failed %d: %s\n", errno,
596 					 strerror_r(errno, sbuf, sizeof(sbuf)));
597 				err = 0;
598 			} else
599 				err = -errno;
600 
601 			break;
602 		}
603 
604 		size += n;
605 	} while (n > 0);
606 
607 	if (!err) {
608 		*sizep = size;
609 		*buf   = bf;
610 	} else
611 		free(bf);
612 
613 	close(fd);
614 	return err;
615 }
616 
617 const char *get_filename_for_perf_kvm(void)
618 {
619 	const char *filename;
620 
621 	if (perf_host && !perf_guest)
622 		filename = strdup("perf.data.host");
623 	else if (!perf_host && perf_guest)
624 		filename = strdup("perf.data.guest");
625 	else
626 		filename = strdup("perf.data.kvm");
627 
628 	return filename;
629 }
630 
631 int perf_event_paranoid(void)
632 {
633 	int value;
634 
635 	if (sysctl__read_int("kernel/perf_event_paranoid", &value))
636 		return INT_MAX;
637 
638 	return value;
639 }
640 
641 void mem_bswap_32(void *src, int byte_size)
642 {
643 	u32 *m = src;
644 	while (byte_size > 0) {
645 		*m = bswap_32(*m);
646 		byte_size -= sizeof(u32);
647 		++m;
648 	}
649 }
650 
651 void mem_bswap_64(void *src, int byte_size)
652 {
653 	u64 *m = src;
654 
655 	while (byte_size > 0) {
656 		*m = bswap_64(*m);
657 		byte_size -= sizeof(u64);
658 		++m;
659 	}
660 }
661 
662 bool find_process(const char *name)
663 {
664 	size_t len = strlen(name);
665 	DIR *dir;
666 	struct dirent *d;
667 	int ret = -1;
668 
669 	dir = opendir(procfs__mountpoint());
670 	if (!dir)
671 		return -1;
672 
673 	/* Walk through the directory. */
674 	while (ret && (d = readdir(dir)) != NULL) {
675 		char path[PATH_MAX];
676 		char *data;
677 		size_t size;
678 
679 		if ((d->d_type != DT_DIR) ||
680 		     !strcmp(".", d->d_name) ||
681 		     !strcmp("..", d->d_name))
682 			continue;
683 
684 		scnprintf(path, sizeof(path), "%s/%s/comm",
685 			  procfs__mountpoint(), d->d_name);
686 
687 		if (filename__read_str(path, &data, &size))
688 			continue;
689 
690 		ret = strncmp(name, data, len);
691 		free(data);
692 	}
693 
694 	closedir(dir);
695 	return ret ? false : true;
696 }
697