1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (C) 2008,2009, Steven Rostedt <srostedt@redhat.com> |
4 | */ |
5 | #include <dirent.h> |
6 | #include <mntent.h> |
7 | #include <stdio.h> |
8 | #include <stdlib.h> |
9 | #include <string.h> |
10 | #include <stdarg.h> |
11 | #include <sys/types.h> |
12 | #include <sys/stat.h> |
13 | #include <sys/wait.h> |
14 | #include <fcntl.h> |
15 | #include <unistd.h> |
16 | #include <errno.h> |
17 | #include <stdbool.h> |
18 | #include <linux/list.h> |
19 | #include <linux/kernel.h> |
20 | #include <linux/zalloc.h> |
21 | #include <internal/lib.h> // page_size |
22 | #include <sys/param.h> |
23 | |
24 | #include "trace-event.h" |
25 | #include "tracepoint.h" |
26 | #include <api/fs/tracing_path.h> |
27 | #include "evsel.h" |
28 | #include "debug.h" |
29 | #include "util.h" |
30 | |
31 | #define VERSION "0.6" |
32 | #define MAX_EVENT_LENGTH 512 |
33 | |
34 | static int output_fd; |
35 | |
36 | struct tracepoint_path { |
37 | char *system; |
38 | char *name; |
39 | struct tracepoint_path *next; |
40 | }; |
41 | |
42 | /* unfortunately, you can not stat debugfs or proc files for size */ |
43 | static int record_file(const char *file, ssize_t hdr_sz) |
44 | { |
45 | unsigned long long size = 0; |
46 | char buf[BUFSIZ], *sizep; |
47 | off_t hdr_pos = lseek(output_fd, 0, SEEK_CUR); |
48 | int r, fd; |
49 | int err = -EIO; |
50 | |
51 | fd = open(file, O_RDONLY); |
52 | if (fd < 0) { |
53 | pr_debug("Can't read '%s'" , file); |
54 | return -errno; |
55 | } |
56 | |
57 | /* put in zeros for file size, then fill true size later */ |
58 | if (hdr_sz) { |
59 | if (write(output_fd, &size, hdr_sz) != hdr_sz) |
60 | goto out; |
61 | } |
62 | |
63 | do { |
64 | r = read(fd, buf, BUFSIZ); |
65 | if (r > 0) { |
66 | size += r; |
67 | if (write(output_fd, buf, r) != r) |
68 | goto out; |
69 | } |
70 | } while (r > 0); |
71 | |
72 | /* ugh, handle big-endian hdr_size == 4 */ |
73 | sizep = (char*)&size; |
74 | if (host_is_bigendian()) |
75 | sizep += sizeof(u64) - hdr_sz; |
76 | |
77 | if (hdr_sz && pwrite(output_fd, sizep, hdr_sz, hdr_pos) < 0) { |
78 | pr_debug("writing file size failed\n" ); |
79 | goto out; |
80 | } |
81 | |
82 | err = 0; |
83 | out: |
84 | close(fd); |
85 | return err; |
86 | } |
87 | |
88 | static int (void) |
89 | { |
90 | char *path = get_events_file("header_page" ); |
91 | struct stat st; |
92 | int err = -EIO; |
93 | |
94 | if (!path) { |
95 | pr_debug("can't get tracing/events/header_page" ); |
96 | return -ENOMEM; |
97 | } |
98 | |
99 | if (stat(path, &st) < 0) { |
100 | pr_debug("can't read '%s'" , path); |
101 | goto out; |
102 | } |
103 | |
104 | if (write(output_fd, "header_page" , 12) != 12) { |
105 | pr_debug("can't write header_page\n" ); |
106 | goto out; |
107 | } |
108 | |
109 | if (record_file(file: path, hdr_sz: 8) < 0) { |
110 | pr_debug("can't record header_page file\n" ); |
111 | goto out; |
112 | } |
113 | |
114 | put_events_file(path); |
115 | |
116 | path = get_events_file("header_event" ); |
117 | if (!path) { |
118 | pr_debug("can't get tracing/events/header_event" ); |
119 | err = -ENOMEM; |
120 | goto out; |
121 | } |
122 | |
123 | if (stat(path, &st) < 0) { |
124 | pr_debug("can't read '%s'" , path); |
125 | goto out; |
126 | } |
127 | |
128 | if (write(output_fd, "header_event" , 13) != 13) { |
129 | pr_debug("can't write header_event\n" ); |
130 | goto out; |
131 | } |
132 | |
133 | if (record_file(file: path, hdr_sz: 8) < 0) { |
134 | pr_debug("can't record header_event file\n" ); |
135 | goto out; |
136 | } |
137 | |
138 | err = 0; |
139 | out: |
140 | put_events_file(path); |
141 | return err; |
142 | } |
143 | |
144 | static bool name_in_tp_list(char *sys, struct tracepoint_path *tps) |
145 | { |
146 | while (tps) { |
147 | if (!strcmp(sys, tps->name)) |
148 | return true; |
149 | tps = tps->next; |
150 | } |
151 | |
152 | return false; |
153 | } |
154 | |
155 | #define for_each_event_tps(dir, dent, tps) \ |
156 | while ((dent = readdir(dir))) \ |
157 | if (dent->d_type == DT_DIR && \ |
158 | (strcmp(dent->d_name, ".")) && \ |
159 | (strcmp(dent->d_name, ".."))) \ |
160 | |
161 | static int copy_event_system(const char *sys, struct tracepoint_path *tps) |
162 | { |
163 | struct dirent *dent; |
164 | struct stat st; |
165 | char *format; |
166 | DIR *dir; |
167 | int count = 0; |
168 | int ret; |
169 | int err; |
170 | |
171 | dir = opendir(sys); |
172 | if (!dir) { |
173 | pr_debug("can't read directory '%s'" , sys); |
174 | return -errno; |
175 | } |
176 | |
177 | for_each_event_tps(dir, dent, tps) { |
178 | if (!name_in_tp_list(sys: dent->d_name, tps)) |
179 | continue; |
180 | |
181 | if (asprintf(&format, "%s/%s/format" , sys, dent->d_name) < 0) { |
182 | err = -ENOMEM; |
183 | goto out; |
184 | } |
185 | ret = stat(format, &st); |
186 | free(format); |
187 | if (ret < 0) |
188 | continue; |
189 | count++; |
190 | } |
191 | |
192 | if (write(output_fd, &count, 4) != 4) { |
193 | err = -EIO; |
194 | pr_debug("can't write count\n" ); |
195 | goto out; |
196 | } |
197 | |
198 | rewinddir(dir); |
199 | for_each_event_tps(dir, dent, tps) { |
200 | if (!name_in_tp_list(sys: dent->d_name, tps)) |
201 | continue; |
202 | |
203 | if (asprintf(&format, "%s/%s/format" , sys, dent->d_name) < 0) { |
204 | err = -ENOMEM; |
205 | goto out; |
206 | } |
207 | ret = stat(format, &st); |
208 | |
209 | if (ret >= 0) { |
210 | err = record_file(file: format, hdr_sz: 8); |
211 | if (err) { |
212 | free(format); |
213 | goto out; |
214 | } |
215 | } |
216 | free(format); |
217 | } |
218 | err = 0; |
219 | out: |
220 | closedir(dir); |
221 | return err; |
222 | } |
223 | |
224 | static int record_ftrace_files(struct tracepoint_path *tps) |
225 | { |
226 | char *path; |
227 | int ret; |
228 | |
229 | path = get_events_file("ftrace" ); |
230 | if (!path) { |
231 | pr_debug("can't get tracing/events/ftrace" ); |
232 | return -ENOMEM; |
233 | } |
234 | |
235 | ret = copy_event_system(sys: path, tps); |
236 | |
237 | put_tracing_file(path); |
238 | |
239 | return ret; |
240 | } |
241 | |
242 | static bool system_in_tp_list(char *sys, struct tracepoint_path *tps) |
243 | { |
244 | while (tps) { |
245 | if (!strcmp(sys, tps->system)) |
246 | return true; |
247 | tps = tps->next; |
248 | } |
249 | |
250 | return false; |
251 | } |
252 | |
253 | static int record_event_files(struct tracepoint_path *tps) |
254 | { |
255 | struct dirent *dent; |
256 | struct stat st; |
257 | char *path; |
258 | char *sys; |
259 | DIR *dir; |
260 | int count = 0; |
261 | int ret; |
262 | int err; |
263 | |
264 | path = get_tracing_file("events" ); |
265 | if (!path) { |
266 | pr_debug("can't get tracing/events" ); |
267 | return -ENOMEM; |
268 | } |
269 | |
270 | dir = opendir(path); |
271 | if (!dir) { |
272 | err = -errno; |
273 | pr_debug("can't read directory '%s'" , path); |
274 | goto out; |
275 | } |
276 | |
277 | for_each_event_tps(dir, dent, tps) { |
278 | if (strcmp(dent->d_name, "ftrace" ) == 0 || |
279 | !system_in_tp_list(sys: dent->d_name, tps)) |
280 | continue; |
281 | |
282 | count++; |
283 | } |
284 | |
285 | if (write(output_fd, &count, 4) != 4) { |
286 | err = -EIO; |
287 | pr_debug("can't write count\n" ); |
288 | goto out; |
289 | } |
290 | |
291 | rewinddir(dir); |
292 | for_each_event_tps(dir, dent, tps) { |
293 | if (strcmp(dent->d_name, "ftrace" ) == 0 || |
294 | !system_in_tp_list(sys: dent->d_name, tps)) |
295 | continue; |
296 | |
297 | if (asprintf(&sys, "%s/%s" , path, dent->d_name) < 0) { |
298 | err = -ENOMEM; |
299 | goto out; |
300 | } |
301 | ret = stat(sys, &st); |
302 | if (ret >= 0) { |
303 | ssize_t size = strlen(dent->d_name) + 1; |
304 | |
305 | if (write(output_fd, dent->d_name, size) != size || |
306 | copy_event_system(sys, tps) < 0) { |
307 | err = -EIO; |
308 | free(sys); |
309 | goto out; |
310 | } |
311 | } |
312 | free(sys); |
313 | } |
314 | err = 0; |
315 | out: |
316 | if (dir) |
317 | closedir(dir); |
318 | put_tracing_file(path); |
319 | |
320 | return err; |
321 | } |
322 | |
323 | static int record_proc_kallsyms(void) |
324 | { |
325 | unsigned long long size = 0; |
326 | /* |
327 | * Just to keep older perf.data file parsers happy, record a zero |
328 | * sized kallsyms file, i.e. do the same thing that was done when |
329 | * /proc/kallsyms (or something specified via --kallsyms, in a |
330 | * different path) couldn't be read. |
331 | */ |
332 | return write(output_fd, &size, 4) != 4 ? -EIO : 0; |
333 | } |
334 | |
335 | static int record_ftrace_printk(void) |
336 | { |
337 | unsigned int size; |
338 | char *path; |
339 | struct stat st; |
340 | int ret, err = 0; |
341 | |
342 | path = get_tracing_file("printk_formats" ); |
343 | if (!path) { |
344 | pr_debug("can't get tracing/printk_formats" ); |
345 | return -ENOMEM; |
346 | } |
347 | |
348 | ret = stat(path, &st); |
349 | if (ret < 0) { |
350 | /* not found */ |
351 | size = 0; |
352 | if (write(output_fd, &size, 4) != 4) |
353 | err = -EIO; |
354 | goto out; |
355 | } |
356 | err = record_file(file: path, hdr_sz: 4); |
357 | |
358 | out: |
359 | put_tracing_file(path); |
360 | return err; |
361 | } |
362 | |
363 | static int record_saved_cmdline(void) |
364 | { |
365 | unsigned long long size; |
366 | char *path; |
367 | struct stat st; |
368 | int ret, err = 0; |
369 | |
370 | path = get_tracing_file("saved_cmdlines" ); |
371 | if (!path) { |
372 | pr_debug("can't get tracing/saved_cmdline" ); |
373 | return -ENOMEM; |
374 | } |
375 | |
376 | ret = stat(path, &st); |
377 | if (ret < 0) { |
378 | /* not found */ |
379 | size = 0; |
380 | if (write(output_fd, &size, 8) != 8) |
381 | err = -EIO; |
382 | goto out; |
383 | } |
384 | err = record_file(file: path, hdr_sz: 8); |
385 | |
386 | out: |
387 | put_tracing_file(path); |
388 | return err; |
389 | } |
390 | |
391 | static void |
392 | put_tracepoints_path(struct tracepoint_path *tps) |
393 | { |
394 | while (tps) { |
395 | struct tracepoint_path *t = tps; |
396 | |
397 | tps = tps->next; |
398 | zfree(&t->name); |
399 | zfree(&t->system); |
400 | free(t); |
401 | } |
402 | } |
403 | |
404 | static struct tracepoint_path *tracepoint_id_to_path(u64 config) |
405 | { |
406 | struct tracepoint_path *path = NULL; |
407 | DIR *sys_dir, *evt_dir; |
408 | struct dirent *sys_dirent, *evt_dirent; |
409 | char id_buf[24]; |
410 | int fd; |
411 | u64 id; |
412 | char evt_path[MAXPATHLEN]; |
413 | char *dir_path; |
414 | |
415 | sys_dir = tracing_events__opendir(); |
416 | if (!sys_dir) |
417 | return NULL; |
418 | |
419 | for_each_subsystem(sys_dir, sys_dirent) { |
420 | dir_path = get_events_file(sys_dirent->d_name); |
421 | if (!dir_path) |
422 | continue; |
423 | evt_dir = opendir(dir_path); |
424 | if (!evt_dir) |
425 | goto next; |
426 | |
427 | for_each_event(dir_path, evt_dir, evt_dirent) { |
428 | |
429 | scnprintf(evt_path, MAXPATHLEN, "%s/%s/id" , dir_path, |
430 | evt_dirent->d_name); |
431 | fd = open(evt_path, O_RDONLY); |
432 | if (fd < 0) |
433 | continue; |
434 | if (read(fd, id_buf, sizeof(id_buf)) < 0) { |
435 | close(fd); |
436 | continue; |
437 | } |
438 | close(fd); |
439 | id = atoll(id_buf); |
440 | if (id == config) { |
441 | put_events_file(dir_path); |
442 | closedir(evt_dir); |
443 | closedir(sys_dir); |
444 | path = zalloc(sizeof(*path)); |
445 | if (!path) |
446 | return NULL; |
447 | if (asprintf(&path->system, "%.*s" , |
448 | MAX_EVENT_LENGTH, sys_dirent->d_name) < 0) { |
449 | free(path); |
450 | return NULL; |
451 | } |
452 | if (asprintf(&path->name, "%.*s" , |
453 | MAX_EVENT_LENGTH, evt_dirent->d_name) < 0) { |
454 | zfree(&path->system); |
455 | free(path); |
456 | return NULL; |
457 | } |
458 | return path; |
459 | } |
460 | } |
461 | closedir(evt_dir); |
462 | next: |
463 | put_events_file(dir_path); |
464 | } |
465 | |
466 | closedir(sys_dir); |
467 | return NULL; |
468 | } |
469 | |
470 | char *tracepoint_id_to_name(u64 config) |
471 | { |
472 | struct tracepoint_path *path = tracepoint_id_to_path(config); |
473 | char *buf = NULL; |
474 | |
475 | if (path && asprintf(&buf, "%s:%s" , path->system, path->name) < 0) |
476 | buf = NULL; |
477 | |
478 | put_tracepoints_path(tps: path); |
479 | return buf; |
480 | } |
481 | |
482 | static struct tracepoint_path *tracepoint_name_to_path(const char *name) |
483 | { |
484 | struct tracepoint_path *path = zalloc(sizeof(*path)); |
485 | char *str = strchr(name, ':'); |
486 | |
487 | if (path == NULL || str == NULL) { |
488 | free(path); |
489 | return NULL; |
490 | } |
491 | |
492 | path->system = strndup(name, str - name); |
493 | path->name = strdup(str+1); |
494 | |
495 | if (path->system == NULL || path->name == NULL) { |
496 | zfree(&path->system); |
497 | zfree(&path->name); |
498 | zfree(&path); |
499 | } |
500 | |
501 | return path; |
502 | } |
503 | |
504 | static struct tracepoint_path * |
505 | get_tracepoints_path(struct list_head *pattrs) |
506 | { |
507 | struct tracepoint_path path, *ppath = &path; |
508 | struct evsel *pos; |
509 | int nr_tracepoints = 0; |
510 | |
511 | list_for_each_entry(pos, pattrs, core.node) { |
512 | if (pos->core.attr.type != PERF_TYPE_TRACEPOINT) |
513 | continue; |
514 | ++nr_tracepoints; |
515 | |
516 | if (pos->name) { |
517 | ppath->next = tracepoint_name_to_path(name: pos->name); |
518 | if (ppath->next) |
519 | goto next; |
520 | |
521 | if (strchr(pos->name, ':') == NULL) |
522 | goto try_id; |
523 | |
524 | goto error; |
525 | } |
526 | |
527 | try_id: |
528 | ppath->next = tracepoint_id_to_path(config: pos->core.attr.config); |
529 | if (!ppath->next) { |
530 | error: |
531 | pr_debug("No memory to alloc tracepoints list\n" ); |
532 | put_tracepoints_path(tps: path.next); |
533 | return NULL; |
534 | } |
535 | next: |
536 | ppath = ppath->next; |
537 | } |
538 | |
539 | return nr_tracepoints > 0 ? path.next : NULL; |
540 | } |
541 | |
542 | bool have_tracepoints(struct list_head *pattrs) |
543 | { |
544 | struct evsel *pos; |
545 | |
546 | list_for_each_entry(pos, pattrs, core.node) |
547 | if (pos->core.attr.type == PERF_TYPE_TRACEPOINT) |
548 | return true; |
549 | |
550 | return false; |
551 | } |
552 | |
553 | static int (void) |
554 | { |
555 | char buf[20]; |
556 | ssize_t size; |
557 | |
558 | /* just guessing this is someone's birthday.. ;) */ |
559 | buf[0] = 23; |
560 | buf[1] = 8; |
561 | buf[2] = 68; |
562 | memcpy(buf + 3, "tracing" , 7); |
563 | |
564 | if (write(output_fd, buf, 10) != 10) |
565 | return -1; |
566 | |
567 | size = strlen(VERSION) + 1; |
568 | if (write(output_fd, VERSION, size) != size) |
569 | return -1; |
570 | |
571 | /* save endian */ |
572 | if (host_is_bigendian()) |
573 | buf[0] = 1; |
574 | else |
575 | buf[0] = 0; |
576 | |
577 | if (write(output_fd, buf, 1) != 1) |
578 | return -1; |
579 | |
580 | /* save size of long */ |
581 | buf[0] = sizeof(long); |
582 | if (write(output_fd, buf, 1) != 1) |
583 | return -1; |
584 | |
585 | /* save page_size */ |
586 | if (write(output_fd, &page_size, 4) != 4) |
587 | return -1; |
588 | |
589 | return 0; |
590 | } |
591 | |
592 | struct tracing_data *tracing_data_get(struct list_head *pattrs, |
593 | int fd, bool temp) |
594 | { |
595 | struct tracepoint_path *tps; |
596 | struct tracing_data *tdata; |
597 | int err; |
598 | |
599 | output_fd = fd; |
600 | |
601 | tps = get_tracepoints_path(pattrs); |
602 | if (!tps) |
603 | return NULL; |
604 | |
605 | tdata = malloc(sizeof(*tdata)); |
606 | if (!tdata) |
607 | return NULL; |
608 | |
609 | tdata->temp = temp; |
610 | tdata->size = 0; |
611 | |
612 | if (temp) { |
613 | int temp_fd; |
614 | |
615 | snprintf(buf: tdata->temp_file, size: sizeof(tdata->temp_file), |
616 | fmt: "/tmp/perf-XXXXXX" ); |
617 | if (!mkstemp(tdata->temp_file)) { |
618 | pr_debug("Can't make temp file" ); |
619 | free(tdata); |
620 | return NULL; |
621 | } |
622 | |
623 | temp_fd = open(tdata->temp_file, O_RDWR); |
624 | if (temp_fd < 0) { |
625 | pr_debug("Can't read '%s'" , tdata->temp_file); |
626 | free(tdata); |
627 | return NULL; |
628 | } |
629 | |
630 | /* |
631 | * Set the temp file the default output, so all the |
632 | * tracing data are stored into it. |
633 | */ |
634 | output_fd = temp_fd; |
635 | } |
636 | |
637 | err = tracing_data_header(); |
638 | if (err) |
639 | goto out; |
640 | err = record_header_files(); |
641 | if (err) |
642 | goto out; |
643 | err = record_ftrace_files(tps); |
644 | if (err) |
645 | goto out; |
646 | err = record_event_files(tps); |
647 | if (err) |
648 | goto out; |
649 | err = record_proc_kallsyms(); |
650 | if (err) |
651 | goto out; |
652 | err = record_ftrace_printk(); |
653 | if (err) |
654 | goto out; |
655 | err = record_saved_cmdline(); |
656 | |
657 | out: |
658 | /* |
659 | * All tracing data are stored by now, we can restore |
660 | * the default output file in case we used temp file. |
661 | */ |
662 | if (temp) { |
663 | tdata->size = lseek(output_fd, 0, SEEK_CUR); |
664 | close(output_fd); |
665 | output_fd = fd; |
666 | } |
667 | |
668 | if (err) |
669 | zfree(&tdata); |
670 | |
671 | put_tracepoints_path(tps); |
672 | return tdata; |
673 | } |
674 | |
675 | int tracing_data_put(struct tracing_data *tdata) |
676 | { |
677 | int err = 0; |
678 | |
679 | if (tdata->temp) { |
680 | err = record_file(file: tdata->temp_file, hdr_sz: 0); |
681 | unlink(tdata->temp_file); |
682 | } |
683 | |
684 | free(tdata); |
685 | return err; |
686 | } |
687 | |
688 | int read_tracing_data(int fd, struct list_head *pattrs) |
689 | { |
690 | int err; |
691 | struct tracing_data *tdata; |
692 | |
693 | /* |
694 | * We work over the real file, so we can write data |
695 | * directly, no temp file is needed. |
696 | */ |
697 | tdata = tracing_data_get(pattrs, fd, temp: false); |
698 | if (!tdata) |
699 | return -ENOMEM; |
700 | |
701 | err = tracing_data_put(tdata); |
702 | return err; |
703 | } |
704 | |