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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
34static int output_fd;
35
36struct 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 */
43static 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;
83out:
84 close(fd);
85 return err;
86}
87
88static int record_header_files(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(path, 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(path, 8) < 0) {
134 pr_debug("can't record header_event file\n");
135 goto out;
136 }
137
138 err = 0;
139out:
140 put_events_file(path);
141 return err;
142}
143
144static 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
161static 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(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(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(format, 8);
211 if (err) {
212 free(format);
213 goto out;
214 }
215 }
216 free(format);
217 }
218 err = 0;
219out:
220 closedir(dir);
221 return err;
222}
223
224static 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(path, tps);
236
237 put_tracing_file(path);
238
239 return ret;
240}
241
242static 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
253static 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(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(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;
315out:
316 closedir(dir);
317 put_tracing_file(path);
318
319 return err;
320}
321
322static int record_proc_kallsyms(void)
323{
324 unsigned long long size = 0;
325 /*
326 * Just to keep older perf.data file parsers happy, record a zero
327 * sized kallsyms file, i.e. do the same thing that was done when
328 * /proc/kallsyms (or something specified via --kallsyms, in a
329 * different path) couldn't be read.
330 */
331 return write(output_fd, &size, 4) != 4 ? -EIO : 0;
332}
333
334static int record_ftrace_printk(void)
335{
336 unsigned int size;
337 char *path;
338 struct stat st;
339 int ret, err = 0;
340
341 path = get_tracing_file("printk_formats");
342 if (!path) {
343 pr_debug("can't get tracing/printk_formats");
344 return -ENOMEM;
345 }
346
347 ret = stat(path, &st);
348 if (ret < 0) {
349 /* not found */
350 size = 0;
351 if (write(output_fd, &size, 4) != 4)
352 err = -EIO;
353 goto out;
354 }
355 err = record_file(path, 4);
356
357out:
358 put_tracing_file(path);
359 return err;
360}
361
362static int record_saved_cmdline(void)
363{
364 unsigned long long size;
365 char *path;
366 struct stat st;
367 int ret, err = 0;
368
369 path = get_tracing_file("saved_cmdlines");
370 if (!path) {
371 pr_debug("can't get tracing/saved_cmdline");
372 return -ENOMEM;
373 }
374
375 ret = stat(path, &st);
376 if (ret < 0) {
377 /* not found */
378 size = 0;
379 if (write(output_fd, &size, 8) != 8)
380 err = -EIO;
381 goto out;
382 }
383 err = record_file(path, 8);
384
385out:
386 put_tracing_file(path);
387 return err;
388}
389
390static void
391put_tracepoints_path(struct tracepoint_path *tps)
392{
393 while (tps) {
394 struct tracepoint_path *t = tps;
395
396 tps = tps->next;
397 zfree(&t->name);
398 zfree(&t->system);
399 free(t);
400 }
401}
402
403static struct tracepoint_path *tracepoint_id_to_path(u64 config)
404{
405 struct tracepoint_path *path = NULL;
406 DIR *sys_dir, *evt_dir;
407 struct dirent *sys_dirent, *evt_dirent;
408 char id_buf[24];
409 int fd;
410 u64 id;
411 char evt_path[MAXPATHLEN];
412 char *dir_path;
413
414 sys_dir = tracing_events__opendir();
415 if (!sys_dir)
416 return NULL;
417
418 for_each_subsystem(sys_dir, sys_dirent) {
419 dir_path = get_events_file(sys_dirent->d_name);
420 if (!dir_path)
421 continue;
422 evt_dir = opendir(dir_path);
423 if (!evt_dir)
424 goto next;
425
426 for_each_event(dir_path, evt_dir, evt_dirent) {
427
428 scnprintf(evt_path, MAXPATHLEN, "%s/%s/id", dir_path,
429 evt_dirent->d_name);
430 fd = open(evt_path, O_RDONLY);
431 if (fd < 0)
432 continue;
433 if (read(fd, id_buf, sizeof(id_buf)) < 0) {
434 close(fd);
435 continue;
436 }
437 close(fd);
438 id = atoll(id_buf);
439 if (id == config) {
440 put_events_file(dir_path);
441 closedir(evt_dir);
442 closedir(sys_dir);
443 path = zalloc(sizeof(*path));
444 if (!path)
445 return NULL;
446 if (asprintf(&path->system, "%.*s",
447 MAX_EVENT_LENGTH, sys_dirent->d_name) < 0) {
448 free(path);
449 return NULL;
450 }
451 if (asprintf(&path->name, "%.*s",
452 MAX_EVENT_LENGTH, evt_dirent->d_name) < 0) {
453 zfree(&path->system);
454 free(path);
455 return NULL;
456 }
457 return path;
458 }
459 }
460 closedir(evt_dir);
461next:
462 put_events_file(dir_path);
463 }
464
465 closedir(sys_dir);
466 return NULL;
467}
468
469static struct tracepoint_path *tracepoint_name_to_path(const char *name)
470{
471 struct tracepoint_path *path = zalloc(sizeof(*path));
472 char *str = strchr(name, ':');
473
474 if (path == NULL || str == NULL) {
475 free(path);
476 return NULL;
477 }
478
479 path->system = strndup(name, str - name);
480 path->name = strdup(str+1);
481
482 if (path->system == NULL || path->name == NULL) {
483 zfree(&path->system);
484 zfree(&path->name);
485 zfree(&path);
486 }
487
488 return path;
489}
490
491static struct tracepoint_path *
492get_tracepoints_path(struct list_head *pattrs)
493{
494 struct tracepoint_path path, *ppath = &path;
495 struct evsel *pos;
496 int nr_tracepoints = 0;
497
498 list_for_each_entry(pos, pattrs, core.node) {
499 if (pos->core.attr.type != PERF_TYPE_TRACEPOINT)
500 continue;
501 ++nr_tracepoints;
502
503 if (pos->name) {
504 ppath->next = tracepoint_name_to_path(pos->name);
505 if (ppath->next)
506 goto next;
507
508 if (strchr(pos->name, ':') == NULL)
509 goto try_id;
510
511 goto error;
512 }
513
514try_id:
515 ppath->next = tracepoint_id_to_path(pos->core.attr.config);
516 if (!ppath->next) {
517error:
518 pr_debug("No memory to alloc tracepoints list\n");
519 put_tracepoints_path(path.next);
520 return NULL;
521 }
522next:
523 ppath = ppath->next;
524 }
525
526 return nr_tracepoints > 0 ? path.next : NULL;
527}
528
529bool have_tracepoints(struct list_head *pattrs)
530{
531 struct evsel *pos;
532
533 list_for_each_entry(pos, pattrs, core.node)
534 if (pos->core.attr.type == PERF_TYPE_TRACEPOINT)
535 return true;
536
537 return false;
538}
539
540static int tracing_data_header(void)
541{
542 char buf[20];
543 ssize_t size;
544
545 /* just guessing this is someone's birthday.. ;) */
546 buf[0] = 23;
547 buf[1] = 8;
548 buf[2] = 68;
549 memcpy(buf + 3, "tracing", 7);
550
551 if (write(output_fd, buf, 10) != 10)
552 return -1;
553
554 size = strlen(VERSION) + 1;
555 if (write(output_fd, VERSION, size) != size)
556 return -1;
557
558 /* save endian */
559 if (host_is_bigendian())
560 buf[0] = 1;
561 else
562 buf[0] = 0;
563
564 if (write(output_fd, buf, 1) != 1)
565 return -1;
566
567 /* save size of long */
568 buf[0] = sizeof(long);
569 if (write(output_fd, buf, 1) != 1)
570 return -1;
571
572 /* save page_size */
573 if (write(output_fd, &page_size, 4) != 4)
574 return -1;
575
576 return 0;
577}
578
579struct tracing_data *tracing_data_get(struct list_head *pattrs,
580 int fd, bool temp)
581{
582 struct tracepoint_path *tps;
583 struct tracing_data *tdata;
584 int err;
585
586 output_fd = fd;
587
588 tps = get_tracepoints_path(pattrs);
589 if (!tps)
590 return NULL;
591
592 tdata = malloc(sizeof(*tdata));
593 if (!tdata)
594 return NULL;
595
596 tdata->temp = temp;
597 tdata->size = 0;
598
599 if (temp) {
600 int temp_fd;
601
602 snprintf(tdata->temp_file, sizeof(tdata->temp_file),
603 "/tmp/perf-XXXXXX");
604 if (!mkstemp(tdata->temp_file)) {
605 pr_debug("Can't make temp file");
606 free(tdata);
607 return NULL;
608 }
609
610 temp_fd = open(tdata->temp_file, O_RDWR);
611 if (temp_fd < 0) {
612 pr_debug("Can't read '%s'", tdata->temp_file);
613 free(tdata);
614 return NULL;
615 }
616
617 /*
618 * Set the temp file the default output, so all the
619 * tracing data are stored into it.
620 */
621 output_fd = temp_fd;
622 }
623
624 err = tracing_data_header();
625 if (err)
626 goto out;
627 err = record_header_files();
628 if (err)
629 goto out;
630 err = record_ftrace_files(tps);
631 if (err)
632 goto out;
633 err = record_event_files(tps);
634 if (err)
635 goto out;
636 err = record_proc_kallsyms();
637 if (err)
638 goto out;
639 err = record_ftrace_printk();
640 if (err)
641 goto out;
642 err = record_saved_cmdline();
643
644out:
645 /*
646 * All tracing data are stored by now, we can restore
647 * the default output file in case we used temp file.
648 */
649 if (temp) {
650 tdata->size = lseek(output_fd, 0, SEEK_CUR);
651 close(output_fd);
652 output_fd = fd;
653 }
654
655 if (err)
656 zfree(&tdata);
657
658 put_tracepoints_path(tps);
659 return tdata;
660}
661
662int tracing_data_put(struct tracing_data *tdata)
663{
664 int err = 0;
665
666 if (tdata->temp) {
667 err = record_file(tdata->temp_file, 0);
668 unlink(tdata->temp_file);
669 }
670
671 free(tdata);
672 return err;
673}
674
675int read_tracing_data(int fd, struct list_head *pattrs)
676{
677 int err;
678 struct tracing_data *tdata;
679
680 /*
681 * We work over the real file, so we can write data
682 * directly, no temp file is needed.
683 */
684 tdata = tracing_data_get(pattrs, fd, false);
685 if (!tdata)
686 return -ENOMEM;
687
688 err = tracing_data_put(tdata);
689 return err;
690}
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
23#include "trace-event.h"
24#include <api/fs/tracing_path.h>
25#include "evsel.h"
26#include "debug.h"
27
28#define VERSION "0.6"
29
30static int output_fd;
31
32
33int bigendian(void)
34{
35 unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0};
36 unsigned int *ptr;
37
38 ptr = (unsigned int *)(void *)str;
39 return *ptr == 0x01020304;
40}
41
42/* unfortunately, you can not stat debugfs or proc files for size */
43static 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 (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;
83out:
84 close(fd);
85 return err;
86}
87
88static int record_header_files(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(path, 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(path, 8) < 0) {
134 pr_debug("can't record header_event file\n");
135 goto out;
136 }
137
138 err = 0;
139out:
140 put_events_file(path);
141 return err;
142}
143
144static 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(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
161static 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(dir, dent, tps) {
178 if (!name_in_tp_list(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(dir, dent, tps) {
200 if (!name_in_tp_list(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(format, 8);
211 if (err) {
212 free(format);
213 goto out;
214 }
215 }
216 free(format);
217 }
218 err = 0;
219out:
220 closedir(dir);
221 return err;
222}
223
224static 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(path, tps);
236
237 put_tracing_file(path);
238
239 return ret;
240}
241
242static 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
253static 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(dir, dent, tps) {
278 if (strcmp(dent->d_name, "ftrace") == 0 ||
279 !system_in_tp_list(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(dir, dent, tps) {
293 if (strcmp(dent->d_name, "ftrace") == 0 ||
294 !system_in_tp_list(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;
315out:
316 closedir(dir);
317 put_tracing_file(path);
318
319 return err;
320}
321
322static int record_proc_kallsyms(void)
323{
324 unsigned long long size = 0;
325 /*
326 * Just to keep older perf.data file parsers happy, record a zero
327 * sized kallsyms file, i.e. do the same thing that was done when
328 * /proc/kallsyms (or something specified via --kallsyms, in a
329 * different path) couldn't be read.
330 */
331 return write(output_fd, &size, 4) != 4 ? -EIO : 0;
332}
333
334static int record_ftrace_printk(void)
335{
336 unsigned int size;
337 char *path;
338 struct stat st;
339 int ret, err = 0;
340
341 path = get_tracing_file("printk_formats");
342 if (!path) {
343 pr_debug("can't get tracing/printk_formats");
344 return -ENOMEM;
345 }
346
347 ret = stat(path, &st);
348 if (ret < 0) {
349 /* not found */
350 size = 0;
351 if (write(output_fd, &size, 4) != 4)
352 err = -EIO;
353 goto out;
354 }
355 err = record_file(path, 4);
356
357out:
358 put_tracing_file(path);
359 return err;
360}
361
362static int record_saved_cmdline(void)
363{
364 unsigned long long size;
365 char *path;
366 struct stat st;
367 int ret, err = 0;
368
369 path = get_tracing_file("saved_cmdlines");
370 if (!path) {
371 pr_debug("can't get tracing/saved_cmdline");
372 return -ENOMEM;
373 }
374
375 ret = stat(path, &st);
376 if (ret < 0) {
377 /* not found */
378 size = 0;
379 if (write(output_fd, &size, 8) != 8)
380 err = -EIO;
381 goto out;
382 }
383 err = record_file(path, 8);
384
385out:
386 put_tracing_file(path);
387 return err;
388}
389
390static void
391put_tracepoints_path(struct tracepoint_path *tps)
392{
393 while (tps) {
394 struct tracepoint_path *t = tps;
395
396 tps = tps->next;
397 zfree(&t->name);
398 zfree(&t->system);
399 free(t);
400 }
401}
402
403static struct tracepoint_path *
404get_tracepoints_path(struct list_head *pattrs)
405{
406 struct tracepoint_path path, *ppath = &path;
407 struct evsel *pos;
408 int nr_tracepoints = 0;
409
410 list_for_each_entry(pos, pattrs, core.node) {
411 if (pos->core.attr.type != PERF_TYPE_TRACEPOINT)
412 continue;
413 ++nr_tracepoints;
414
415 if (pos->name) {
416 ppath->next = tracepoint_name_to_path(pos->name);
417 if (ppath->next)
418 goto next;
419
420 if (strchr(pos->name, ':') == NULL)
421 goto try_id;
422
423 goto error;
424 }
425
426try_id:
427 ppath->next = tracepoint_id_to_path(pos->core.attr.config);
428 if (!ppath->next) {
429error:
430 pr_debug("No memory to alloc tracepoints list\n");
431 put_tracepoints_path(&path);
432 return NULL;
433 }
434next:
435 ppath = ppath->next;
436 }
437
438 return nr_tracepoints > 0 ? path.next : NULL;
439}
440
441bool have_tracepoints(struct list_head *pattrs)
442{
443 struct evsel *pos;
444
445 list_for_each_entry(pos, pattrs, core.node)
446 if (pos->core.attr.type == PERF_TYPE_TRACEPOINT)
447 return true;
448
449 return false;
450}
451
452static int tracing_data_header(void)
453{
454 char buf[20];
455 ssize_t size;
456
457 /* just guessing this is someone's birthday.. ;) */
458 buf[0] = 23;
459 buf[1] = 8;
460 buf[2] = 68;
461 memcpy(buf + 3, "tracing", 7);
462
463 if (write(output_fd, buf, 10) != 10)
464 return -1;
465
466 size = strlen(VERSION) + 1;
467 if (write(output_fd, VERSION, size) != size)
468 return -1;
469
470 /* save endian */
471 if (bigendian())
472 buf[0] = 1;
473 else
474 buf[0] = 0;
475
476 if (write(output_fd, buf, 1) != 1)
477 return -1;
478
479 /* save size of long */
480 buf[0] = sizeof(long);
481 if (write(output_fd, buf, 1) != 1)
482 return -1;
483
484 /* save page_size */
485 if (write(output_fd, &page_size, 4) != 4)
486 return -1;
487
488 return 0;
489}
490
491struct tracing_data *tracing_data_get(struct list_head *pattrs,
492 int fd, bool temp)
493{
494 struct tracepoint_path *tps;
495 struct tracing_data *tdata;
496 int err;
497
498 output_fd = fd;
499
500 tps = get_tracepoints_path(pattrs);
501 if (!tps)
502 return NULL;
503
504 tdata = malloc(sizeof(*tdata));
505 if (!tdata)
506 return NULL;
507
508 tdata->temp = temp;
509 tdata->size = 0;
510
511 if (temp) {
512 int temp_fd;
513
514 snprintf(tdata->temp_file, sizeof(tdata->temp_file),
515 "/tmp/perf-XXXXXX");
516 if (!mkstemp(tdata->temp_file)) {
517 pr_debug("Can't make temp file");
518 free(tdata);
519 return NULL;
520 }
521
522 temp_fd = open(tdata->temp_file, O_RDWR);
523 if (temp_fd < 0) {
524 pr_debug("Can't read '%s'", tdata->temp_file);
525 free(tdata);
526 return NULL;
527 }
528
529 /*
530 * Set the temp file the default output, so all the
531 * tracing data are stored into it.
532 */
533 output_fd = temp_fd;
534 }
535
536 err = tracing_data_header();
537 if (err)
538 goto out;
539 err = record_header_files();
540 if (err)
541 goto out;
542 err = record_ftrace_files(tps);
543 if (err)
544 goto out;
545 err = record_event_files(tps);
546 if (err)
547 goto out;
548 err = record_proc_kallsyms();
549 if (err)
550 goto out;
551 err = record_ftrace_printk();
552 if (err)
553 goto out;
554 err = record_saved_cmdline();
555
556out:
557 /*
558 * All tracing data are stored by now, we can restore
559 * the default output file in case we used temp file.
560 */
561 if (temp) {
562 tdata->size = lseek(output_fd, 0, SEEK_CUR);
563 close(output_fd);
564 output_fd = fd;
565 }
566
567 if (err)
568 zfree(&tdata);
569
570 put_tracepoints_path(tps);
571 return tdata;
572}
573
574int tracing_data_put(struct tracing_data *tdata)
575{
576 int err = 0;
577
578 if (tdata->temp) {
579 err = record_file(tdata->temp_file, 0);
580 unlink(tdata->temp_file);
581 }
582
583 free(tdata);
584 return err;
585}
586
587int read_tracing_data(int fd, struct list_head *pattrs)
588{
589 int err;
590 struct tracing_data *tdata;
591
592 /*
593 * We work over the real file, so we can write data
594 * directly, no temp file is needed.
595 */
596 tdata = tracing_data_get(pattrs, fd, false);
597 if (!tdata)
598 return -ENOMEM;
599
600 err = tracing_data_put(tdata);
601 return err;
602}