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 <pthread.h>
32 #include <fcntl.h>
33 #include <unistd.h>
34 #include <errno.h>
35 #include <stdbool.h>
36 #include <linux/list.h>
37 #include <linux/kernel.h>
38
39 #include "../perf.h"
40 #include "trace-event.h"
41 #include <api/fs/tracing_path.h>
42 #include "evsel.h"
43 #include "debug.h"
44
45 #define VERSION "0.6"
46
47 static int output_fd;
48
49
bigendian(void)50 int bigendian(void)
51 {
52 unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0};
53 unsigned int *ptr;
54
55 ptr = (unsigned int *)(void *)str;
56 return *ptr == 0x01020304;
57 }
58
59 /* unfortunately, you can not stat debugfs or proc files for size */
record_file(const char * file,ssize_t hdr_sz)60 static int record_file(const char *file, ssize_t hdr_sz)
61 {
62 unsigned long long size = 0;
63 char buf[BUFSIZ], *sizep;
64 off_t hdr_pos = lseek(output_fd, 0, SEEK_CUR);
65 int r, fd;
66 int err = -EIO;
67
68 fd = open(file, O_RDONLY);
69 if (fd < 0) {
70 pr_debug("Can't read '%s'", file);
71 return -errno;
72 }
73
74 /* put in zeros for file size, then fill true size later */
75 if (hdr_sz) {
76 if (write(output_fd, &size, hdr_sz) != hdr_sz)
77 goto out;
78 }
79
80 do {
81 r = read(fd, buf, BUFSIZ);
82 if (r > 0) {
83 size += r;
84 if (write(output_fd, buf, r) != r)
85 goto out;
86 }
87 } while (r > 0);
88
89 /* ugh, handle big-endian hdr_size == 4 */
90 sizep = (char*)&size;
91 if (bigendian())
92 sizep += sizeof(u64) - hdr_sz;
93
94 if (hdr_sz && pwrite(output_fd, sizep, hdr_sz, hdr_pos) < 0) {
95 pr_debug("writing file size failed\n");
96 goto out;
97 }
98
99 err = 0;
100 out:
101 close(fd);
102 return err;
103 }
104
record_header_files(void)105 static int record_header_files(void)
106 {
107 char *path;
108 struct stat st;
109 int err = -EIO;
110
111 path = get_tracing_file("events/header_page");
112 if (!path) {
113 pr_debug("can't get tracing/events/header_page");
114 return -ENOMEM;
115 }
116
117 if (stat(path, &st) < 0) {
118 pr_debug("can't read '%s'", path);
119 goto out;
120 }
121
122 if (write(output_fd, "header_page", 12) != 12) {
123 pr_debug("can't write header_page\n");
124 goto out;
125 }
126
127 if (record_file(path, 8) < 0) {
128 pr_debug("can't record header_page file\n");
129 goto out;
130 }
131
132 put_tracing_file(path);
133
134 path = get_tracing_file("events/header_event");
135 if (!path) {
136 pr_debug("can't get tracing/events/header_event");
137 err = -ENOMEM;
138 goto out;
139 }
140
141 if (stat(path, &st) < 0) {
142 pr_debug("can't read '%s'", path);
143 goto out;
144 }
145
146 if (write(output_fd, "header_event", 13) != 13) {
147 pr_debug("can't write header_event\n");
148 goto out;
149 }
150
151 if (record_file(path, 8) < 0) {
152 pr_debug("can't record header_event file\n");
153 goto out;
154 }
155
156 err = 0;
157 out:
158 put_tracing_file(path);
159 return err;
160 }
161
name_in_tp_list(char * sys,struct tracepoint_path * tps)162 static bool name_in_tp_list(char *sys, struct tracepoint_path *tps)
163 {
164 while (tps) {
165 if (!strcmp(sys, tps->name))
166 return true;
167 tps = tps->next;
168 }
169
170 return false;
171 }
172
173 #define for_each_event(dir, dent, tps) \
174 while ((dent = readdir(dir))) \
175 if (dent->d_type == DT_DIR && \
176 (strcmp(dent->d_name, ".")) && \
177 (strcmp(dent->d_name, ".."))) \
178
copy_event_system(const char * sys,struct tracepoint_path * tps)179 static int copy_event_system(const char *sys, struct tracepoint_path *tps)
180 {
181 struct dirent *dent;
182 struct stat st;
183 char *format;
184 DIR *dir;
185 int count = 0;
186 int ret;
187 int err;
188
189 dir = opendir(sys);
190 if (!dir) {
191 pr_debug("can't read directory '%s'", sys);
192 return -errno;
193 }
194
195 for_each_event(dir, dent, tps) {
196 if (!name_in_tp_list(dent->d_name, tps))
197 continue;
198
199 if (asprintf(&format, "%s/%s/format", sys, dent->d_name) < 0) {
200 err = -ENOMEM;
201 goto out;
202 }
203 ret = stat(format, &st);
204 free(format);
205 if (ret < 0)
206 continue;
207 count++;
208 }
209
210 if (write(output_fd, &count, 4) != 4) {
211 err = -EIO;
212 pr_debug("can't write count\n");
213 goto out;
214 }
215
216 rewinddir(dir);
217 for_each_event(dir, dent, tps) {
218 if (!name_in_tp_list(dent->d_name, tps))
219 continue;
220
221 if (asprintf(&format, "%s/%s/format", sys, dent->d_name) < 0) {
222 err = -ENOMEM;
223 goto out;
224 }
225 ret = stat(format, &st);
226
227 if (ret >= 0) {
228 err = record_file(format, 8);
229 if (err) {
230 free(format);
231 goto out;
232 }
233 }
234 free(format);
235 }
236 err = 0;
237 out:
238 closedir(dir);
239 return err;
240 }
241
record_ftrace_files(struct tracepoint_path * tps)242 static int record_ftrace_files(struct tracepoint_path *tps)
243 {
244 char *path;
245 int ret;
246
247 path = get_tracing_file("events/ftrace");
248 if (!path) {
249 pr_debug("can't get tracing/events/ftrace");
250 return -ENOMEM;
251 }
252
253 ret = copy_event_system(path, tps);
254
255 put_tracing_file(path);
256
257 return ret;
258 }
259
system_in_tp_list(char * sys,struct tracepoint_path * tps)260 static bool system_in_tp_list(char *sys, struct tracepoint_path *tps)
261 {
262 while (tps) {
263 if (!strcmp(sys, tps->system))
264 return true;
265 tps = tps->next;
266 }
267
268 return false;
269 }
270
record_event_files(struct tracepoint_path * tps)271 static int record_event_files(struct tracepoint_path *tps)
272 {
273 struct dirent *dent;
274 struct stat st;
275 char *path;
276 char *sys;
277 DIR *dir;
278 int count = 0;
279 int ret;
280 int err;
281
282 path = get_tracing_file("events");
283 if (!path) {
284 pr_debug("can't get tracing/events");
285 return -ENOMEM;
286 }
287
288 dir = opendir(path);
289 if (!dir) {
290 err = -errno;
291 pr_debug("can't read directory '%s'", path);
292 goto out;
293 }
294
295 for_each_event(dir, dent, tps) {
296 if (strcmp(dent->d_name, "ftrace") == 0 ||
297 !system_in_tp_list(dent->d_name, tps))
298 continue;
299
300 count++;
301 }
302
303 if (write(output_fd, &count, 4) != 4) {
304 err = -EIO;
305 pr_debug("can't write count\n");
306 goto out;
307 }
308
309 rewinddir(dir);
310 for_each_event(dir, dent, tps) {
311 if (strcmp(dent->d_name, "ftrace") == 0 ||
312 !system_in_tp_list(dent->d_name, tps))
313 continue;
314
315 if (asprintf(&sys, "%s/%s", path, dent->d_name) < 0) {
316 err = -ENOMEM;
317 goto out;
318 }
319 ret = stat(sys, &st);
320 if (ret >= 0) {
321 ssize_t size = strlen(dent->d_name) + 1;
322
323 if (write(output_fd, dent->d_name, size) != size ||
324 copy_event_system(sys, tps) < 0) {
325 err = -EIO;
326 free(sys);
327 goto out;
328 }
329 }
330 free(sys);
331 }
332 err = 0;
333 out:
334 closedir(dir);
335 put_tracing_file(path);
336
337 return err;
338 }
339
record_proc_kallsyms(void)340 static int record_proc_kallsyms(void)
341 {
342 unsigned long long size = 0;
343 /*
344 * Just to keep older perf.data file parsers happy, record a zero
345 * sized kallsyms file, i.e. do the same thing that was done when
346 * /proc/kallsyms (or something specified via --kallsyms, in a
347 * different path) couldn't be read.
348 */
349 return write(output_fd, &size, 4) != 4 ? -EIO : 0;
350 }
351
record_ftrace_printk(void)352 static int record_ftrace_printk(void)
353 {
354 unsigned int size;
355 char *path;
356 struct stat st;
357 int ret, err = 0;
358
359 path = get_tracing_file("printk_formats");
360 if (!path) {
361 pr_debug("can't get tracing/printk_formats");
362 return -ENOMEM;
363 }
364
365 ret = stat(path, &st);
366 if (ret < 0) {
367 /* not found */
368 size = 0;
369 if (write(output_fd, &size, 4) != 4)
370 err = -EIO;
371 goto out;
372 }
373 err = record_file(path, 4);
374
375 out:
376 put_tracing_file(path);
377 return err;
378 }
379
record_saved_cmdline(void)380 static int record_saved_cmdline(void)
381 {
382 unsigned long long size;
383 char *path;
384 struct stat st;
385 int ret, err = 0;
386
387 path = get_tracing_file("saved_cmdlines");
388 if (!path) {
389 pr_debug("can't get tracing/saved_cmdline");
390 return -ENOMEM;
391 }
392
393 ret = stat(path, &st);
394 if (ret < 0) {
395 /* not found */
396 size = 0;
397 if (write(output_fd, &size, 8) != 8)
398 err = -EIO;
399 goto out;
400 }
401 err = record_file(path, 8);
402
403 out:
404 put_tracing_file(path);
405 return err;
406 }
407
408 static void
put_tracepoints_path(struct tracepoint_path * tps)409 put_tracepoints_path(struct tracepoint_path *tps)
410 {
411 while (tps) {
412 struct tracepoint_path *t = tps;
413
414 tps = tps->next;
415 zfree(&t->name);
416 zfree(&t->system);
417 free(t);
418 }
419 }
420
421 static struct tracepoint_path *
get_tracepoints_path(struct list_head * pattrs)422 get_tracepoints_path(struct list_head *pattrs)
423 {
424 struct tracepoint_path path, *ppath = &path;
425 struct perf_evsel *pos;
426 int nr_tracepoints = 0;
427
428 list_for_each_entry(pos, pattrs, node) {
429 if (pos->attr.type != PERF_TYPE_TRACEPOINT)
430 continue;
431 ++nr_tracepoints;
432
433 if (pos->name) {
434 ppath->next = tracepoint_name_to_path(pos->name);
435 if (ppath->next)
436 goto next;
437
438 if (strchr(pos->name, ':') == NULL)
439 goto try_id;
440
441 goto error;
442 }
443
444 try_id:
445 ppath->next = tracepoint_id_to_path(pos->attr.config);
446 if (!ppath->next) {
447 error:
448 pr_debug("No memory to alloc tracepoints list\n");
449 put_tracepoints_path(&path);
450 return NULL;
451 }
452 next:
453 ppath = ppath->next;
454 }
455
456 return nr_tracepoints > 0 ? path.next : NULL;
457 }
458
have_tracepoints(struct list_head * pattrs)459 bool have_tracepoints(struct list_head *pattrs)
460 {
461 struct perf_evsel *pos;
462
463 list_for_each_entry(pos, pattrs, node)
464 if (pos->attr.type == PERF_TYPE_TRACEPOINT)
465 return true;
466
467 return false;
468 }
469
tracing_data_header(void)470 static int tracing_data_header(void)
471 {
472 char buf[20];
473 ssize_t size;
474
475 /* just guessing this is someone's birthday.. ;) */
476 buf[0] = 23;
477 buf[1] = 8;
478 buf[2] = 68;
479 memcpy(buf + 3, "tracing", 7);
480
481 if (write(output_fd, buf, 10) != 10)
482 return -1;
483
484 size = strlen(VERSION) + 1;
485 if (write(output_fd, VERSION, size) != size)
486 return -1;
487
488 /* save endian */
489 if (bigendian())
490 buf[0] = 1;
491 else
492 buf[0] = 0;
493
494 if (write(output_fd, buf, 1) != 1)
495 return -1;
496
497 /* save size of long */
498 buf[0] = sizeof(long);
499 if (write(output_fd, buf, 1) != 1)
500 return -1;
501
502 /* save page_size */
503 if (write(output_fd, &page_size, 4) != 4)
504 return -1;
505
506 return 0;
507 }
508
tracing_data_get(struct list_head * pattrs,int fd,bool temp)509 struct tracing_data *tracing_data_get(struct list_head *pattrs,
510 int fd, bool temp)
511 {
512 struct tracepoint_path *tps;
513 struct tracing_data *tdata;
514 int err;
515
516 output_fd = fd;
517
518 tps = get_tracepoints_path(pattrs);
519 if (!tps)
520 return NULL;
521
522 tdata = malloc(sizeof(*tdata));
523 if (!tdata)
524 return NULL;
525
526 tdata->temp = temp;
527 tdata->size = 0;
528
529 if (temp) {
530 int temp_fd;
531
532 snprintf(tdata->temp_file, sizeof(tdata->temp_file),
533 "/tmp/perf-XXXXXX");
534 if (!mkstemp(tdata->temp_file)) {
535 pr_debug("Can't make temp file");
536 free(tdata);
537 return NULL;
538 }
539
540 temp_fd = open(tdata->temp_file, O_RDWR);
541 if (temp_fd < 0) {
542 pr_debug("Can't read '%s'", tdata->temp_file);
543 free(tdata);
544 return NULL;
545 }
546
547 /*
548 * Set the temp file the default output, so all the
549 * tracing data are stored into it.
550 */
551 output_fd = temp_fd;
552 }
553
554 err = tracing_data_header();
555 if (err)
556 goto out;
557 err = record_header_files();
558 if (err)
559 goto out;
560 err = record_ftrace_files(tps);
561 if (err)
562 goto out;
563 err = record_event_files(tps);
564 if (err)
565 goto out;
566 err = record_proc_kallsyms();
567 if (err)
568 goto out;
569 err = record_ftrace_printk();
570 if (err)
571 goto out;
572 err = record_saved_cmdline();
573
574 out:
575 /*
576 * All tracing data are stored by now, we can restore
577 * the default output file in case we used temp file.
578 */
579 if (temp) {
580 tdata->size = lseek(output_fd, 0, SEEK_CUR);
581 close(output_fd);
582 output_fd = fd;
583 }
584
585 if (err)
586 zfree(&tdata);
587
588 put_tracepoints_path(tps);
589 return tdata;
590 }
591
tracing_data_put(struct tracing_data * tdata)592 int tracing_data_put(struct tracing_data *tdata)
593 {
594 int err = 0;
595
596 if (tdata->temp) {
597 err = record_file(tdata->temp_file, 0);
598 unlink(tdata->temp_file);
599 }
600
601 free(tdata);
602 return err;
603 }
604
read_tracing_data(int fd,struct list_head * pattrs)605 int read_tracing_data(int fd, struct list_head *pattrs)
606 {
607 int err;
608 struct tracing_data *tdata;
609
610 /*
611 * We work over the real file, so we can write data
612 * directly, no temp file is needed.
613 */
614 tdata = tracing_data_get(pattrs, fd, false);
615 if (!tdata)
616 return -ENOMEM;
617
618 err = tracing_data_put(tdata);
619 return err;
620 }
621