1 /*
2 * Copyright (C) 2008,2009, Steven Rostedt <srostedt@redhat.com>
3 *
4 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; version 2 of the License (not later!)
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 *
19 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
20 */
21 #include "util.h"
22 #include <dirent.h>
23 #include <mntent.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <string.h>
27 #include <stdarg.h>
28 #include <sys/types.h>
29 #include <sys/stat.h>
30 #include <sys/wait.h>
31 #include <fcntl.h>
32 #include <unistd.h>
33 #include <errno.h>
34 #include <stdbool.h>
35 #include <linux/list.h>
36 #include <linux/kernel.h>
37
38 #include "../perf.h"
39 #include "trace-event.h"
40 #include <api/fs/tracing_path.h>
41 #include "evsel.h"
42 #include "debug.h"
43
44 #define VERSION "0.6"
45
46 static int output_fd;
47
48
bigendian(void)49 int bigendian(void)
50 {
51 unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0};
52 unsigned int *ptr;
53
54 ptr = (unsigned int *)(void *)str;
55 return *ptr == 0x01020304;
56 }
57
58 /* unfortunately, you can not stat debugfs or proc files for size */
record_file(const char * file,ssize_t hdr_sz)59 static int record_file(const char *file, ssize_t hdr_sz)
60 {
61 unsigned long long size = 0;
62 char buf[BUFSIZ], *sizep;
63 off_t hdr_pos = lseek(output_fd, 0, SEEK_CUR);
64 int r, fd;
65 int err = -EIO;
66
67 fd = open(file, O_RDONLY);
68 if (fd < 0) {
69 pr_debug("Can't read '%s'", file);
70 return -errno;
71 }
72
73 /* put in zeros for file size, then fill true size later */
74 if (hdr_sz) {
75 if (write(output_fd, &size, hdr_sz) != hdr_sz)
76 goto out;
77 }
78
79 do {
80 r = read(fd, buf, BUFSIZ);
81 if (r > 0) {
82 size += r;
83 if (write(output_fd, buf, r) != r)
84 goto out;
85 }
86 } while (r > 0);
87
88 /* ugh, handle big-endian hdr_size == 4 */
89 sizep = (char*)&size;
90 if (bigendian())
91 sizep += sizeof(u64) - hdr_sz;
92
93 if (hdr_sz && pwrite(output_fd, sizep, hdr_sz, hdr_pos) < 0) {
94 pr_debug("writing file size failed\n");
95 goto out;
96 }
97
98 err = 0;
99 out:
100 close(fd);
101 return err;
102 }
103
record_header_files(void)104 static int record_header_files(void)
105 {
106 char *path = get_events_file("header_page");
107 struct stat st;
108 int err = -EIO;
109
110 if (!path) {
111 pr_debug("can't get tracing/events/header_page");
112 return -ENOMEM;
113 }
114
115 if (stat(path, &st) < 0) {
116 pr_debug("can't read '%s'", path);
117 goto out;
118 }
119
120 if (write(output_fd, "header_page", 12) != 12) {
121 pr_debug("can't write header_page\n");
122 goto out;
123 }
124
125 if (record_file(path, 8) < 0) {
126 pr_debug("can't record header_page file\n");
127 goto out;
128 }
129
130 put_events_file(path);
131
132 path = get_events_file("header_event");
133 if (!path) {
134 pr_debug("can't get tracing/events/header_event");
135 err = -ENOMEM;
136 goto out;
137 }
138
139 if (stat(path, &st) < 0) {
140 pr_debug("can't read '%s'", path);
141 goto out;
142 }
143
144 if (write(output_fd, "header_event", 13) != 13) {
145 pr_debug("can't write header_event\n");
146 goto out;
147 }
148
149 if (record_file(path, 8) < 0) {
150 pr_debug("can't record header_event file\n");
151 goto out;
152 }
153
154 err = 0;
155 out:
156 put_events_file(path);
157 return err;
158 }
159
name_in_tp_list(char * sys,struct tracepoint_path * tps)160 static bool name_in_tp_list(char *sys, struct tracepoint_path *tps)
161 {
162 while (tps) {
163 if (!strcmp(sys, tps->name))
164 return true;
165 tps = tps->next;
166 }
167
168 return false;
169 }
170
171 #define for_each_event(dir, dent, tps) \
172 while ((dent = readdir(dir))) \
173 if (dent->d_type == DT_DIR && \
174 (strcmp(dent->d_name, ".")) && \
175 (strcmp(dent->d_name, ".."))) \
176
copy_event_system(const char * sys,struct tracepoint_path * tps)177 static int copy_event_system(const char *sys, struct tracepoint_path *tps)
178 {
179 struct dirent *dent;
180 struct stat st;
181 char *format;
182 DIR *dir;
183 int count = 0;
184 int ret;
185 int err;
186
187 dir = opendir(sys);
188 if (!dir) {
189 pr_debug("can't read directory '%s'", sys);
190 return -errno;
191 }
192
193 for_each_event(dir, dent, tps) {
194 if (!name_in_tp_list(dent->d_name, tps))
195 continue;
196
197 if (asprintf(&format, "%s/%s/format", sys, dent->d_name) < 0) {
198 err = -ENOMEM;
199 goto out;
200 }
201 ret = stat(format, &st);
202 free(format);
203 if (ret < 0)
204 continue;
205 count++;
206 }
207
208 if (write(output_fd, &count, 4) != 4) {
209 err = -EIO;
210 pr_debug("can't write count\n");
211 goto out;
212 }
213
214 rewinddir(dir);
215 for_each_event(dir, dent, tps) {
216 if (!name_in_tp_list(dent->d_name, tps))
217 continue;
218
219 if (asprintf(&format, "%s/%s/format", sys, dent->d_name) < 0) {
220 err = -ENOMEM;
221 goto out;
222 }
223 ret = stat(format, &st);
224
225 if (ret >= 0) {
226 err = record_file(format, 8);
227 if (err) {
228 free(format);
229 goto out;
230 }
231 }
232 free(format);
233 }
234 err = 0;
235 out:
236 closedir(dir);
237 return err;
238 }
239
record_ftrace_files(struct tracepoint_path * tps)240 static int record_ftrace_files(struct tracepoint_path *tps)
241 {
242 char *path;
243 int ret;
244
245 path = get_events_file("ftrace");
246 if (!path) {
247 pr_debug("can't get tracing/events/ftrace");
248 return -ENOMEM;
249 }
250
251 ret = copy_event_system(path, tps);
252
253 put_tracing_file(path);
254
255 return ret;
256 }
257
system_in_tp_list(char * sys,struct tracepoint_path * tps)258 static bool system_in_tp_list(char *sys, struct tracepoint_path *tps)
259 {
260 while (tps) {
261 if (!strcmp(sys, tps->system))
262 return true;
263 tps = tps->next;
264 }
265
266 return false;
267 }
268
record_event_files(struct tracepoint_path * tps)269 static int record_event_files(struct tracepoint_path *tps)
270 {
271 struct dirent *dent;
272 struct stat st;
273 char *path;
274 char *sys;
275 DIR *dir;
276 int count = 0;
277 int ret;
278 int err;
279
280 path = get_tracing_file("events");
281 if (!path) {
282 pr_debug("can't get tracing/events");
283 return -ENOMEM;
284 }
285
286 dir = opendir(path);
287 if (!dir) {
288 err = -errno;
289 pr_debug("can't read directory '%s'", path);
290 goto out;
291 }
292
293 for_each_event(dir, dent, tps) {
294 if (strcmp(dent->d_name, "ftrace") == 0 ||
295 !system_in_tp_list(dent->d_name, tps))
296 continue;
297
298 count++;
299 }
300
301 if (write(output_fd, &count, 4) != 4) {
302 err = -EIO;
303 pr_debug("can't write count\n");
304 goto out;
305 }
306
307 rewinddir(dir);
308 for_each_event(dir, dent, tps) {
309 if (strcmp(dent->d_name, "ftrace") == 0 ||
310 !system_in_tp_list(dent->d_name, tps))
311 continue;
312
313 if (asprintf(&sys, "%s/%s", path, dent->d_name) < 0) {
314 err = -ENOMEM;
315 goto out;
316 }
317 ret = stat(sys, &st);
318 if (ret >= 0) {
319 ssize_t size = strlen(dent->d_name) + 1;
320
321 if (write(output_fd, dent->d_name, size) != size ||
322 copy_event_system(sys, tps) < 0) {
323 err = -EIO;
324 free(sys);
325 goto out;
326 }
327 }
328 free(sys);
329 }
330 err = 0;
331 out:
332 closedir(dir);
333 put_tracing_file(path);
334
335 return err;
336 }
337
record_proc_kallsyms(void)338 static int record_proc_kallsyms(void)
339 {
340 unsigned long long size = 0;
341 /*
342 * Just to keep older perf.data file parsers happy, record a zero
343 * sized kallsyms file, i.e. do the same thing that was done when
344 * /proc/kallsyms (or something specified via --kallsyms, in a
345 * different path) couldn't be read.
346 */
347 return write(output_fd, &size, 4) != 4 ? -EIO : 0;
348 }
349
record_ftrace_printk(void)350 static int record_ftrace_printk(void)
351 {
352 unsigned int size;
353 char *path;
354 struct stat st;
355 int ret, err = 0;
356
357 path = get_tracing_file("printk_formats");
358 if (!path) {
359 pr_debug("can't get tracing/printk_formats");
360 return -ENOMEM;
361 }
362
363 ret = stat(path, &st);
364 if (ret < 0) {
365 /* not found */
366 size = 0;
367 if (write(output_fd, &size, 4) != 4)
368 err = -EIO;
369 goto out;
370 }
371 err = record_file(path, 4);
372
373 out:
374 put_tracing_file(path);
375 return err;
376 }
377
record_saved_cmdline(void)378 static int record_saved_cmdline(void)
379 {
380 unsigned long long size;
381 char *path;
382 struct stat st;
383 int ret, err = 0;
384
385 path = get_tracing_file("saved_cmdlines");
386 if (!path) {
387 pr_debug("can't get tracing/saved_cmdline");
388 return -ENOMEM;
389 }
390
391 ret = stat(path, &st);
392 if (ret < 0) {
393 /* not found */
394 size = 0;
395 if (write(output_fd, &size, 8) != 8)
396 err = -EIO;
397 goto out;
398 }
399 err = record_file(path, 8);
400
401 out:
402 put_tracing_file(path);
403 return err;
404 }
405
406 static void
put_tracepoints_path(struct tracepoint_path * tps)407 put_tracepoints_path(struct tracepoint_path *tps)
408 {
409 while (tps) {
410 struct tracepoint_path *t = tps;
411
412 tps = tps->next;
413 zfree(&t->name);
414 zfree(&t->system);
415 free(t);
416 }
417 }
418
419 static struct tracepoint_path *
get_tracepoints_path(struct list_head * pattrs)420 get_tracepoints_path(struct list_head *pattrs)
421 {
422 struct tracepoint_path path, *ppath = &path;
423 struct perf_evsel *pos;
424 int nr_tracepoints = 0;
425
426 list_for_each_entry(pos, pattrs, node) {
427 if (pos->attr.type != PERF_TYPE_TRACEPOINT)
428 continue;
429 ++nr_tracepoints;
430
431 if (pos->name) {
432 ppath->next = tracepoint_name_to_path(pos->name);
433 if (ppath->next)
434 goto next;
435
436 if (strchr(pos->name, ':') == NULL)
437 goto try_id;
438
439 goto error;
440 }
441
442 try_id:
443 ppath->next = tracepoint_id_to_path(pos->attr.config);
444 if (!ppath->next) {
445 error:
446 pr_debug("No memory to alloc tracepoints list\n");
447 put_tracepoints_path(&path);
448 return NULL;
449 }
450 next:
451 ppath = ppath->next;
452 }
453
454 return nr_tracepoints > 0 ? path.next : NULL;
455 }
456
have_tracepoints(struct list_head * pattrs)457 bool have_tracepoints(struct list_head *pattrs)
458 {
459 struct perf_evsel *pos;
460
461 list_for_each_entry(pos, pattrs, node)
462 if (pos->attr.type == PERF_TYPE_TRACEPOINT)
463 return true;
464
465 return false;
466 }
467
tracing_data_header(void)468 static int tracing_data_header(void)
469 {
470 char buf[20];
471 ssize_t size;
472
473 /* just guessing this is someone's birthday.. ;) */
474 buf[0] = 23;
475 buf[1] = 8;
476 buf[2] = 68;
477 memcpy(buf + 3, "tracing", 7);
478
479 if (write(output_fd, buf, 10) != 10)
480 return -1;
481
482 size = strlen(VERSION) + 1;
483 if (write(output_fd, VERSION, size) != size)
484 return -1;
485
486 /* save endian */
487 if (bigendian())
488 buf[0] = 1;
489 else
490 buf[0] = 0;
491
492 if (write(output_fd, buf, 1) != 1)
493 return -1;
494
495 /* save size of long */
496 buf[0] = sizeof(long);
497 if (write(output_fd, buf, 1) != 1)
498 return -1;
499
500 /* save page_size */
501 if (write(output_fd, &page_size, 4) != 4)
502 return -1;
503
504 return 0;
505 }
506
tracing_data_get(struct list_head * pattrs,int fd,bool temp)507 struct tracing_data *tracing_data_get(struct list_head *pattrs,
508 int fd, bool temp)
509 {
510 struct tracepoint_path *tps;
511 struct tracing_data *tdata;
512 int err;
513
514 output_fd = fd;
515
516 tps = get_tracepoints_path(pattrs);
517 if (!tps)
518 return NULL;
519
520 tdata = malloc(sizeof(*tdata));
521 if (!tdata)
522 return NULL;
523
524 tdata->temp = temp;
525 tdata->size = 0;
526
527 if (temp) {
528 int temp_fd;
529
530 snprintf(tdata->temp_file, sizeof(tdata->temp_file),
531 "/tmp/perf-XXXXXX");
532 if (!mkstemp(tdata->temp_file)) {
533 pr_debug("Can't make temp file");
534 return NULL;
535 }
536
537 temp_fd = open(tdata->temp_file, O_RDWR);
538 if (temp_fd < 0) {
539 pr_debug("Can't read '%s'", tdata->temp_file);
540 return NULL;
541 }
542
543 /*
544 * Set the temp file the default output, so all the
545 * tracing data are stored into it.
546 */
547 output_fd = temp_fd;
548 }
549
550 err = tracing_data_header();
551 if (err)
552 goto out;
553 err = record_header_files();
554 if (err)
555 goto out;
556 err = record_ftrace_files(tps);
557 if (err)
558 goto out;
559 err = record_event_files(tps);
560 if (err)
561 goto out;
562 err = record_proc_kallsyms();
563 if (err)
564 goto out;
565 err = record_ftrace_printk();
566 if (err)
567 goto out;
568 err = record_saved_cmdline();
569
570 out:
571 /*
572 * All tracing data are stored by now, we can restore
573 * the default output file in case we used temp file.
574 */
575 if (temp) {
576 tdata->size = lseek(output_fd, 0, SEEK_CUR);
577 close(output_fd);
578 output_fd = fd;
579 }
580
581 if (err)
582 zfree(&tdata);
583
584 put_tracepoints_path(tps);
585 return tdata;
586 }
587
tracing_data_put(struct tracing_data * tdata)588 int tracing_data_put(struct tracing_data *tdata)
589 {
590 int err = 0;
591
592 if (tdata->temp) {
593 err = record_file(tdata->temp_file, 0);
594 unlink(tdata->temp_file);
595 }
596
597 free(tdata);
598 return err;
599 }
600
read_tracing_data(int fd,struct list_head * pattrs)601 int read_tracing_data(int fd, struct list_head *pattrs)
602 {
603 int err;
604 struct tracing_data *tdata;
605
606 /*
607 * We work over the real file, so we can write data
608 * directly, no temp file is needed.
609 */
610 tdata = tracing_data_get(pattrs, fd, false);
611 if (!tdata)
612 return -ENOMEM;
613
614 err = tracing_data_put(tdata);
615 return err;
616 }
617
