Add multipoll and change tracectl to use it
[ust.git] / libust / tracectl.c
1 /* Copyright (C) 2009 Pierre-Marc Fournier
2 *
3 * This library is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU Lesser General Public
5 * License as published by the Free Software Foundation; either
6 * version 2.1 of the License, or (at your option) any later version.
7 *
8 * This library is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * Lesser General Public License for more details.
12 *
13 * You should have received a copy of the GNU Lesser General Public
14 * License along with this library; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
16 */
17
18 #define _GNU_SOURCE
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <stdint.h>
22 #include <signal.h>
23 #include <sys/types.h>
24 #include <sys/socket.h>
25 #include <sys/un.h>
26 #include <fcntl.h>
27 #include <poll.h>
28 #include <regex.h>
29 #include <urcu/uatomic_arch.h>
30
31 #include <ust/marker.h>
32 #include <ust/tracectl.h>
33 #include "tracer.h"
34 #include "usterr.h"
35 #include "ustcomm.h"
36 #include "buffers.h"
37 #include "marker-control.h"
38 #include "multipoll.h"
39
40 #define USTSIGNAL SIGIO
41
42 #define MAX_MSG_SIZE (100)
43 #define MSG_NOTIF 1
44 #define MSG_REGISTER_NOTIF 2
45
46 char consumer_stack[10000];
47
48 /* This should only be accessed by the constructor, before the creation
49 * of the listener, and then only by the listener.
50 */
51 s64 pidunique = -1LL;
52
53 struct list_head blocked_consumers = LIST_HEAD_INIT(blocked_consumers);
54
55 static struct ustcomm_app ustcomm_app;
56
57 struct tracecmd { /* no padding */
58 uint32_t size;
59 uint16_t command;
60 };
61
62 /* volatile because shared between the listener and the main thread */
63 volatile sig_atomic_t buffers_to_export = 0;
64
65 struct trctl_msg {
66 /* size: the size of all the fields except size itself */
67 uint32_t size;
68 uint16_t type;
69 /* Only the necessary part of the payload is transferred. It
70 * may even be none of it.
71 */
72 char payload[94];
73 };
74
75 struct consumer_channel {
76 int fd;
77 struct ltt_channel_struct *chan;
78 };
79
80 struct blocked_consumer {
81 int fd_consumer;
82 int fd_producer;
83 int tmp_poll_idx;
84
85 /* args to ustcomm_send_reply */
86 struct ustcomm_server server;
87 struct ustcomm_source src;
88
89 /* args to ust_buffers_get_subbuf */
90 struct ust_buffer *buf;
91
92 struct list_head list;
93 };
94
95 static long long make_pidunique(void)
96 {
97 s64 retval;
98 struct timeval tv;
99
100 gettimeofday(&tv, NULL);
101
102 retval = tv.tv_sec;
103 retval <<= 32;
104 retval |= tv.tv_usec;
105
106 return retval;
107 }
108
109 static void print_markers(FILE *fp)
110 {
111 struct marker_iter iter;
112
113 lock_markers();
114 marker_iter_reset(&iter);
115 marker_iter_start(&iter);
116
117 while(iter.marker) {
118 fprintf(fp, "marker: %s/%s %d \"%s\" %p\n", iter.marker->channel, iter.marker->name, (int)imv_read(iter.marker->state), iter.marker->format, iter.marker->location);
119 marker_iter_next(&iter);
120 }
121 unlock_markers();
122 }
123
124 static int init_socket(void);
125
126 int fd_notif = -1;
127 void notif_cb(void)
128 {
129 int result;
130 struct trctl_msg msg;
131
132 /* FIXME: fd_notif should probably be protected by a spinlock */
133
134 if(fd_notif == -1)
135 return;
136
137 msg.type = MSG_NOTIF;
138 msg.size = sizeof(msg.type);
139
140 /* FIXME: don't block here */
141 result = write(fd_notif, &msg, msg.size+sizeof(msg.size));
142 if(result == -1) {
143 PERROR("write");
144 return;
145 }
146 }
147
148 /* Ask the daemon to collect a trace called trace_name and being
149 * produced by this pid.
150 *
151 * The trace must be at least allocated. (It can also be started.)
152 * This is because _ltt_trace_find is used.
153 */
154
155 static void inform_consumer_daemon(const char *trace_name)
156 {
157 int i,j;
158 struct ust_trace *trace;
159 pid_t pid = getpid();
160 int result;
161
162 ltt_lock_traces();
163
164 trace = _ltt_trace_find(trace_name);
165 if(trace == NULL) {
166 WARN("inform_consumer_daemon: could not find trace \"%s\"; it is probably already destroyed", trace_name);
167 goto finish;
168 }
169
170 for(i=0; i < trace->nr_channels; i++) {
171 /* iterate on all cpus */
172 for(j=0; j<trace->channels[i].n_cpus; j++) {
173 char *buf;
174 asprintf(&buf, "%s_%d", trace->channels[i].channel_name, j);
175 result = ustcomm_request_consumer(pid, buf);
176 if(result == -1) {
177 WARN("Failed to request collection for channel %s. Is the daemon available?", trace->channels[i].channel_name);
178 /* continue even if fail */
179 }
180 free(buf);
181 buffers_to_export++;
182 }
183 }
184
185 finish:
186 ltt_unlock_traces();
187 }
188
189 int process_blkd_consumer_act(void *priv, int fd, short events)
190 {
191 int result;
192 long consumed_old = 0;
193 char *reply;
194 struct blocked_consumer *bc = (struct blocked_consumer *) priv;
195 char inbuf;
196
197 result = read(bc->fd_producer, &inbuf, 1);
198 if(result == -1) {
199 PERROR("read");
200 return -1;
201 }
202 if(result == 0) {
203 int res;
204 DBG("listener: got messsage that a buffer ended");
205
206 res = close(bc->fd_producer);
207 if(res == -1) {
208 PERROR("close");
209 }
210
211 list_del(&bc->list);
212
213 result = ustcomm_send_reply(&bc->server, "END", &bc->src);
214 if(result < 0) {
215 ERR("ustcomm_send_reply failed");
216 return -1;
217 }
218
219 return 0;
220 }
221
222 result = ust_buffers_get_subbuf(bc->buf, &consumed_old);
223 if(result == -EAGAIN) {
224 WARN("missed buffer?");
225 return 0;
226 }
227 else if(result < 0) {
228 ERR("ust_buffers_get_subbuf: error: %s", strerror(-result));
229 }
230 asprintf(&reply, "%s %ld", "OK", consumed_old);
231 result = ustcomm_send_reply(&bc->server, reply, &bc->src);
232 if(result < 0) {
233 ERR("ustcomm_send_reply failed");
234 free(reply);
235 return -1;
236 }
237 free(reply);
238
239 list_del(&bc->list);
240
241 return 0;
242 }
243
244 void blocked_consumers_add_to_mp(struct mpentries *ent)
245 {
246 struct blocked_consumer *bc;
247
248 list_for_each_entry(bc, &blocked_consumers, list) {
249 multipoll_add(ent, bc->fd_producer, POLLIN, process_blkd_consumer_act, bc, NULL);
250 }
251
252 }
253
254 void seperate_channel_cpu(const char *channel_and_cpu, char **channel, int *cpu)
255 {
256 const char *sep;
257
258 sep = rindex(channel_and_cpu, '_');
259 if(sep == NULL) {
260 *cpu = -1;
261 sep = channel_and_cpu + strlen(channel_and_cpu);
262 }
263 else {
264 *cpu = atoi(sep+1);
265 }
266
267 asprintf(channel, "%.*s", (int)(sep-channel_and_cpu), channel_and_cpu);
268 }
269
270 static int do_cmd_get_shmid(const char *recvbuf, struct ustcomm_source *src)
271 {
272 int retval = 0;
273 struct ust_trace *trace;
274 char trace_name[] = "auto";
275 int i;
276 char *channel_and_cpu;
277 int found = 0;
278 int result;
279 char *ch_name;
280 int ch_cpu;
281
282 DBG("get_shmid");
283
284 channel_and_cpu = nth_token(recvbuf, 1);
285 if(channel_and_cpu == NULL) {
286 ERR("cannot parse channel");
287 goto end;
288 }
289
290 seperate_channel_cpu(channel_and_cpu, &ch_name, &ch_cpu);
291 if(ch_cpu == -1) {
292 ERR("problem parsing channel name");
293 goto free_short_chan_name;
294 }
295
296 ltt_lock_traces();
297 trace = _ltt_trace_find(trace_name);
298 ltt_unlock_traces();
299
300 if(trace == NULL) {
301 ERR("cannot find trace!");
302 retval = -1;
303 goto free_short_chan_name;
304 }
305
306 for(i=0; i<trace->nr_channels; i++) {
307 struct ust_channel *channel = &trace->channels[i];
308 struct ust_buffer *buf = channel->buf[ch_cpu];
309
310 if(!strcmp(trace->channels[i].channel_name, ch_name)) {
311 char *reply;
312
313 // DBG("the shmid for the requested channel is %d", buf->shmid);
314 // DBG("the shmid for its buffer structure is %d", channel->buf_struct_shmids);
315 asprintf(&reply, "%d %d", buf->shmid, channel->buf_struct_shmids[ch_cpu]);
316
317 result = ustcomm_send_reply(&ustcomm_app.server, reply, src);
318 if(result) {
319 ERR("ustcomm_send_reply failed");
320 free(reply);
321 retval = -1;
322 goto free_short_chan_name;
323 }
324
325 free(reply);
326
327 found = 1;
328 break;
329 }
330 }
331
332 if(!found) {
333 ERR("channel not found (%s)", channel_and_cpu);
334 }
335
336 free_short_chan_name:
337 free(ch_name);
338
339 end:
340 return retval;
341 }
342
343 static int do_cmd_get_n_subbufs(const char *recvbuf, struct ustcomm_source *src)
344 {
345 int retval = 0;
346 struct ust_trace *trace;
347 char trace_name[] = "auto";
348 int i;
349 char *channel_and_cpu;
350 int found = 0;
351 int result;
352 char *ch_name;
353 int ch_cpu;
354
355 DBG("get_n_subbufs");
356
357 channel_and_cpu = nth_token(recvbuf, 1);
358 if(channel_and_cpu == NULL) {
359 ERR("cannot parse channel");
360 goto end;
361 }
362
363 seperate_channel_cpu(channel_and_cpu, &ch_name, &ch_cpu);
364 if(ch_cpu == -1) {
365 ERR("problem parsing channel name");
366 goto free_short_chan_name;
367 }
368
369 ltt_lock_traces();
370 trace = _ltt_trace_find(trace_name);
371 ltt_unlock_traces();
372
373 if(trace == NULL) {
374 ERR("cannot find trace!");
375 retval = -1;
376 goto free_short_chan_name;
377 }
378
379 for(i=0; i<trace->nr_channels; i++) {
380 struct ust_channel *channel = &trace->channels[i];
381
382 if(!strcmp(trace->channels[i].channel_name, ch_name)) {
383 char *reply;
384
385 DBG("the n_subbufs for the requested channel is %d", channel->subbuf_cnt);
386 asprintf(&reply, "%d", channel->subbuf_cnt);
387
388 result = ustcomm_send_reply(&ustcomm_app.server, reply, src);
389 if(result) {
390 ERR("ustcomm_send_reply failed");
391 free(reply);
392 retval = -1;
393 goto free_short_chan_name;
394 }
395
396 free(reply);
397 found = 1;
398 break;
399 }
400 }
401 if(found == 0) {
402 ERR("unable to find channel");
403 }
404
405 free_short_chan_name:
406 free(ch_name);
407
408 end:
409 return retval;
410 }
411
412 static int do_cmd_get_subbuf_size(const char *recvbuf, struct ustcomm_source *src)
413 {
414 int retval = 0;
415 struct ust_trace *trace;
416 char trace_name[] = "auto";
417 int i;
418 char *channel_and_cpu;
419 int found = 0;
420 int result;
421 char *ch_name;
422 int ch_cpu;
423
424 DBG("get_subbuf_size");
425
426 channel_and_cpu = nth_token(recvbuf, 1);
427 if(channel_and_cpu == NULL) {
428 ERR("cannot parse channel");
429 goto end;
430 }
431
432 seperate_channel_cpu(channel_and_cpu, &ch_name, &ch_cpu);
433 if(ch_cpu == -1) {
434 ERR("problem parsing channel name");
435 goto free_short_chan_name;
436 }
437
438 ltt_lock_traces();
439 trace = _ltt_trace_find(trace_name);
440 ltt_unlock_traces();
441
442 if(trace == NULL) {
443 ERR("cannot find trace!");
444 retval = -1;
445 goto free_short_chan_name;
446 }
447
448 for(i=0; i<trace->nr_channels; i++) {
449 struct ust_channel *channel = &trace->channels[i];
450
451 if(!strcmp(trace->channels[i].channel_name, ch_name)) {
452 char *reply;
453
454 DBG("the subbuf_size for the requested channel is %zd", channel->subbuf_size);
455 asprintf(&reply, "%zd", channel->subbuf_size);
456
457 result = ustcomm_send_reply(&ustcomm_app.server, reply, src);
458 if(result) {
459 ERR("ustcomm_send_reply failed");
460 free(reply);
461 retval = -1;
462 goto free_short_chan_name;
463 }
464
465 free(reply);
466 found = 1;
467 break;
468 }
469 }
470 if(found == 0) {
471 ERR("unable to find channel");
472 }
473
474 free_short_chan_name:
475 free(ch_name);
476
477 end:
478 return retval;
479 }
480
481 static unsigned int poweroftwo(unsigned int x)
482 {
483 unsigned int power2 = 1;
484 unsigned int hardcoded = 2147483648; /* FIX max 2^31 */
485
486 if (x < 2)
487 return 2;
488
489 while (power2 < x && power2 < hardcoded)
490 power2 *= 2;
491
492 return power2;
493 }
494
495 static int do_cmd_set_subbuf_size(const char *recvbuf, struct ustcomm_source *src)
496 {
497 char *channel_slash_size;
498 char ch_name[256]="";
499 unsigned int size, power;
500 int retval = 0;
501 struct ust_trace *trace;
502 char trace_name[] = "auto";
503 int i;
504 int found = 0;
505
506 DBG("set_subbuf_size");
507
508 channel_slash_size = nth_token(recvbuf, 1);
509 sscanf(channel_slash_size, "%255[^/]/%u", ch_name, &size);
510
511 if(ch_name == NULL) {
512 ERR("cannot parse channel");
513 goto end;
514 }
515
516 power = poweroftwo(size);
517 if (power != size)
518 WARN("using the next 2^n = %u\n", power);
519
520 ltt_lock_traces();
521 trace = _ltt_trace_find_setup(trace_name);
522 if(trace == NULL) {
523 ERR("cannot find trace!");
524 retval = -1;
525 goto end;
526 }
527
528 for(i = 0; i < trace->nr_channels; i++) {
529 struct ust_channel *channel = &trace->channels[i];
530
531 if(!strcmp(trace->channels[i].channel_name, ch_name)) {
532
533 channel->subbuf_size = power;
534 DBG("the set_subbuf_size for the requested channel is %zd", channel->subbuf_size);
535
536 found = 1;
537 break;
538 }
539 }
540 if(found == 0) {
541 ERR("unable to find channel");
542 }
543
544 end:
545 ltt_unlock_traces();
546 return retval;
547 }
548
549 static int do_cmd_set_subbuf_num(const char *recvbuf, struct ustcomm_source *src)
550 {
551 char *channel_slash_num;
552 char ch_name[256]="";
553 unsigned int num;
554 int retval = 0;
555 struct ust_trace *trace;
556 char trace_name[] = "auto";
557 int i;
558 int found = 0;
559
560 DBG("set_subbuf_num");
561
562 channel_slash_num = nth_token(recvbuf, 1);
563 sscanf(channel_slash_num, "%255[^/]/%u", ch_name, &num);
564
565 if(ch_name == NULL) {
566 ERR("cannot parse channel");
567 goto end;
568 }
569 if (num < 2) {
570 ERR("subbuffer count should be greater than 2");
571 goto end;
572 }
573
574 ltt_lock_traces();
575 trace = _ltt_trace_find_setup(trace_name);
576 if(trace == NULL) {
577 ERR("cannot find trace!");
578 retval = -1;
579 goto end;
580 }
581
582 for(i = 0; i < trace->nr_channels; i++) {
583 struct ust_channel *channel = &trace->channels[i];
584
585 if(!strcmp(trace->channels[i].channel_name, ch_name)) {
586
587 channel->subbuf_cnt = num;
588 DBG("the set_subbuf_cnt for the requested channel is %zd", channel->subbuf_cnt);
589
590 found = 1;
591 break;
592 }
593 }
594 if(found == 0) {
595 ERR("unable to find channel");
596 }
597
598 end:
599 ltt_unlock_traces();
600 return retval;
601 }
602
603 static int do_cmd_get_subbuffer(const char *recvbuf, struct ustcomm_source *src)
604 {
605 int retval = 0;
606 struct ust_trace *trace;
607 char trace_name[] = "auto";
608 int i;
609 char *channel_and_cpu;
610 int found = 0;
611 char *ch_name;
612 int ch_cpu;
613
614 DBG("get_subbuf");
615
616 channel_and_cpu = nth_token(recvbuf, 1);
617 if(channel_and_cpu == NULL) {
618 ERR("cannot parse channel");
619 goto end;
620 }
621
622 seperate_channel_cpu(channel_and_cpu, &ch_name, &ch_cpu);
623 if(ch_cpu == -1) {
624 ERR("problem parsing channel name");
625 goto free_short_chan_name;
626 }
627
628 ltt_lock_traces();
629 trace = _ltt_trace_find(trace_name);
630
631 if(trace == NULL) {
632 int result;
633
634 DBG("Cannot find trace. It was likely destroyed by the user.");
635 result = ustcomm_send_reply(&ustcomm_app.server, "NOTFOUND", src);
636 if(result) {
637 ERR("ustcomm_send_reply failed");
638 retval = -1;
639 goto unlock_traces;
640 }
641
642 goto unlock_traces;
643 }
644
645 for(i=0; i<trace->nr_channels; i++) {
646 struct ust_channel *channel = &trace->channels[i];
647
648 if(!strcmp(trace->channels[i].channel_name, ch_name)) {
649 struct ust_buffer *buf = channel->buf[ch_cpu];
650 struct blocked_consumer *bc;
651
652 found = 1;
653
654 bc = (struct blocked_consumer *) malloc(sizeof(struct blocked_consumer));
655 if(bc == NULL) {
656 ERR("malloc returned NULL");
657 goto unlock_traces;
658 }
659 bc->fd_consumer = src->fd;
660 bc->fd_producer = buf->data_ready_fd_read;
661 bc->buf = buf;
662 bc->src = *src;
663 bc->server = ustcomm_app.server;
664
665 list_add(&bc->list, &blocked_consumers);
666
667 /* Being here is the proof the daemon has mapped the buffer in its
668 * memory. We may now decrement buffers_to_export.
669 */
670 if(uatomic_read(&buf->consumed) == 0) {
671 DBG("decrementing buffers_to_export");
672 buffers_to_export--;
673 }
674
675 break;
676 }
677 }
678 if(found == 0) {
679 ERR("unable to find channel");
680 }
681
682 unlock_traces:
683 ltt_unlock_traces();
684
685 free_short_chan_name:
686 free(ch_name);
687
688 end:
689 return retval;
690 }
691
692 static int do_cmd_put_subbuffer(const char *recvbuf, struct ustcomm_source *src)
693 {
694 int retval = 0;
695 struct ust_trace *trace;
696 char trace_name[] = "auto";
697 int i;
698 char *channel_and_cpu;
699 int found = 0;
700 int result;
701 char *ch_name;
702 int ch_cpu;
703 long consumed_old;
704 char *consumed_old_str;
705 char *endptr;
706 char *reply = NULL;
707
708 DBG("put_subbuf");
709
710 channel_and_cpu = strdup_malloc(nth_token(recvbuf, 1));
711 if(channel_and_cpu == NULL) {
712 ERR("cannot parse channel");
713 retval = -1;
714 goto end;
715 }
716
717 consumed_old_str = strdup_malloc(nth_token(recvbuf, 2));
718 if(consumed_old_str == NULL) {
719 ERR("cannot parse consumed_old");
720 retval = -1;
721 goto free_channel_and_cpu;
722 }
723 consumed_old = strtol(consumed_old_str, &endptr, 10);
724 if(*endptr != '\0') {
725 ERR("invalid value for consumed_old");
726 retval = -1;
727 goto free_consumed_old_str;
728 }
729
730 seperate_channel_cpu(channel_and_cpu, &ch_name, &ch_cpu);
731 if(ch_cpu == -1) {
732 ERR("problem parsing channel name");
733 retval = -1;
734 goto free_short_chan_name;
735 }
736
737 ltt_lock_traces();
738 trace = _ltt_trace_find(trace_name);
739
740 if(trace == NULL) {
741 DBG("Cannot find trace. It was likely destroyed by the user.");
742 result = ustcomm_send_reply(&ustcomm_app.server, "NOTFOUND", src);
743 if(result) {
744 ERR("ustcomm_send_reply failed");
745 retval = -1;
746 goto unlock_traces;
747 }
748
749 goto unlock_traces;
750 }
751
752 for(i=0; i<trace->nr_channels; i++) {
753 struct ust_channel *channel = &trace->channels[i];
754
755 if(!strcmp(trace->channels[i].channel_name, ch_name)) {
756 struct ust_buffer *buf = channel->buf[ch_cpu];
757
758 found = 1;
759
760 result = ust_buffers_put_subbuf(buf, consumed_old);
761 if(result < 0) {
762 WARN("ust_buffers_put_subbuf: error (subbuf=%s)", channel_and_cpu);
763 asprintf(&reply, "%s", "ERROR");
764 }
765 else {
766 DBG("ust_buffers_put_subbuf: success (subbuf=%s)", channel_and_cpu);
767 asprintf(&reply, "%s", "OK");
768 }
769
770 result = ustcomm_send_reply(&ustcomm_app.server, reply, src);
771 if(result) {
772 ERR("ustcomm_send_reply failed");
773 free(reply);
774 retval = -1;
775 goto unlock_traces;
776 }
777
778 free(reply);
779 break;
780 }
781 }
782 if(found == 0) {
783 ERR("unable to find channel");
784 }
785
786 unlock_traces:
787 ltt_unlock_traces();
788 free_short_chan_name:
789 free(ch_name);
790 free_consumed_old_str:
791 free(consumed_old_str);
792 free_channel_and_cpu:
793 free(channel_and_cpu);
794
795 end:
796 return retval;
797 }
798
799 static void listener_cleanup(void *ptr)
800 {
801 ustcomm_fini_app(&ustcomm_app, 0);
802 }
803
804 int process_client_cmd(char *recvbuf, struct ustcomm_source *src)
805 {
806 int result;
807 char trace_name[] = "auto";
808 char trace_type[] = "ustrelay";
809 int len;
810
811 DBG("received a message! it's: %s", recvbuf);
812 len = strlen(recvbuf);
813
814 if(!strcmp(recvbuf, "print_markers")) {
815 print_markers(stderr);
816 }
817 else if(!strcmp(recvbuf, "list_markers")) {
818 char *ptr;
819 size_t size;
820 FILE *fp;
821
822 fp = open_memstream(&ptr, &size);
823 print_markers(fp);
824 fclose(fp);
825
826 result = ustcomm_send_reply(&ustcomm_app.server, ptr, src);
827
828 free(ptr);
829 }
830 else if(!strcmp(recvbuf, "start")) {
831 /* start is an operation that setups the trace, allocates it and starts it */
832 result = ltt_trace_setup(trace_name);
833 if(result < 0) {
834 ERR("ltt_trace_setup failed");
835 return -1;
836 }
837
838 result = ltt_trace_set_type(trace_name, trace_type);
839 if(result < 0) {
840 ERR("ltt_trace_set_type failed");
841 return -1;
842 }
843
844 result = ltt_trace_alloc(trace_name);
845 if(result < 0) {
846 ERR("ltt_trace_alloc failed");
847 return -1;
848 }
849
850 inform_consumer_daemon(trace_name);
851
852 result = ltt_trace_start(trace_name);
853 if(result < 0) {
854 ERR("ltt_trace_start failed");
855 return -1;
856 }
857 }
858 else if(!strcmp(recvbuf, "trace_setup")) {
859 DBG("trace setup");
860
861 result = ltt_trace_setup(trace_name);
862 if(result < 0) {
863 ERR("ltt_trace_setup failed");
864 return -1;
865 }
866
867 result = ltt_trace_set_type(trace_name, trace_type);
868 if(result < 0) {
869 ERR("ltt_trace_set_type failed");
870 return -1;
871 }
872 }
873 else if(!strcmp(recvbuf, "trace_alloc")) {
874 DBG("trace alloc");
875
876 result = ltt_trace_alloc(trace_name);
877 if(result < 0) {
878 ERR("ltt_trace_alloc failed");
879 return -1;
880 }
881 inform_consumer_daemon(trace_name);
882 }
883 else if(!strcmp(recvbuf, "trace_create")) {
884 DBG("trace create");
885
886 result = ltt_trace_setup(trace_name);
887 if(result < 0) {
888 ERR("ltt_trace_setup failed");
889 return -1;
890 }
891
892 result = ltt_trace_set_type(trace_name, trace_type);
893 if(result < 0) {
894 ERR("ltt_trace_set_type failed");
895 return -1;
896 }
897 }
898 else if(!strcmp(recvbuf, "trace_start")) {
899 DBG("trace start");
900
901 result = ltt_trace_alloc(trace_name);
902 if(result < 0) {
903 ERR("ltt_trace_alloc failed");
904 return -1;
905 }
906 if(!result) {
907 inform_consumer_daemon(trace_name);
908 }
909
910 result = ltt_trace_start(trace_name);
911 if(result < 0) {
912 ERR("ltt_trace_start failed");
913 return -1;
914 }
915 }
916 else if(!strcmp(recvbuf, "trace_stop")) {
917 DBG("trace stop");
918
919 result = ltt_trace_stop(trace_name);
920 if(result < 0) {
921 ERR("ltt_trace_stop failed");
922 return -1;
923 }
924 }
925 else if(!strcmp(recvbuf, "trace_destroy")) {
926
927 DBG("trace destroy");
928
929 result = ltt_trace_destroy(trace_name, 0);
930 if(result < 0) {
931 ERR("ltt_trace_destroy failed");
932 return -1;
933 }
934 }
935 else if(nth_token_is(recvbuf, "get_shmid", 0) == 1) {
936 do_cmd_get_shmid(recvbuf, src);
937 }
938 else if(nth_token_is(recvbuf, "get_n_subbufs", 0) == 1) {
939 do_cmd_get_n_subbufs(recvbuf, src);
940 }
941 else if(nth_token_is(recvbuf, "get_subbuf_size", 0) == 1) {
942 do_cmd_get_subbuf_size(recvbuf, src);
943 }
944 else if(nth_token_is(recvbuf, "load_probe_lib", 0) == 1) {
945 char *libfile;
946
947 libfile = nth_token(recvbuf, 1);
948
949 DBG("load_probe_lib loading %s", libfile);
950
951 free(libfile);
952 }
953 else if(nth_token_is(recvbuf, "get_subbuffer", 0) == 1) {
954 do_cmd_get_subbuffer(recvbuf, src);
955 }
956 else if(nth_token_is(recvbuf, "put_subbuffer", 0) == 1) {
957 do_cmd_put_subbuffer(recvbuf, src);
958 }
959 else if(nth_token_is(recvbuf, "set_subbuf_size", 0) == 1) {
960 do_cmd_set_subbuf_size(recvbuf, src);
961 }
962 else if(nth_token_is(recvbuf, "set_subbuf_num", 0) == 1) {
963 do_cmd_set_subbuf_num(recvbuf, src);
964 }
965 else if(nth_token_is(recvbuf, "enable_marker", 0) == 1) {
966 char *channel_slash_name = nth_token(recvbuf, 1);
967 char channel_name[256]="";
968 char marker_name[256]="";
969
970 result = sscanf(channel_slash_name, "%255[^/]/%255s", channel_name, marker_name);
971
972 if(channel_name == NULL || marker_name == NULL) {
973 WARN("invalid marker name");
974 goto next_cmd;
975 }
976
977 result = ltt_marker_connect(channel_name, marker_name, "default");
978 if(result < 0) {
979 WARN("could not enable marker; channel=%s, name=%s", channel_name, marker_name);
980 }
981 }
982 else if(nth_token_is(recvbuf, "disable_marker", 0) == 1) {
983 char *channel_slash_name = nth_token(recvbuf, 1);
984 char *marker_name;
985 char *channel_name;
986
987 result = sscanf(channel_slash_name, "%a[^/]/%as", &channel_name, &marker_name);
988
989 if(marker_name == NULL) {
990 }
991
992 result = ltt_marker_disconnect(channel_name, marker_name, "default");
993 if(result < 0) {
994 WARN("could not disable marker; channel=%s, name=%s", channel_name, marker_name);
995 }
996 }
997 else if(nth_token_is(recvbuf, "get_pidunique", 0) == 1) {
998 char *reply;
999
1000 asprintf(&reply, "%lld", pidunique);
1001
1002 result = ustcomm_send_reply(&ustcomm_app.server, reply, src);
1003 if(result) {
1004 ERR("listener: get_pidunique: ustcomm_send_reply failed");
1005 goto next_cmd;
1006 }
1007
1008 free(reply);
1009 }
1010 // else if(nth_token_is(recvbuf, "get_notifications", 0) == 1) {
1011 // struct ust_trace *trace;
1012 // char trace_name[] = "auto";
1013 // int i;
1014 // char *channel_name;
1015 //
1016 // DBG("get_notifications");
1017 //
1018 // channel_name = strdup_malloc(nth_token(recvbuf, 1));
1019 // if(channel_name == NULL) {
1020 // ERR("put_subbuf_size: cannot parse channel");
1021 // goto next_cmd;
1022 // }
1023 //
1024 // ltt_lock_traces();
1025 // trace = _ltt_trace_find(trace_name);
1026 // ltt_unlock_traces();
1027 //
1028 // if(trace == NULL) {
1029 // ERR("cannot find trace!");
1030 // return (void *)1;
1031 // }
1032 //
1033 // for(i=0; i<trace->nr_channels; i++) {
1034 // struct rchan *rchan = trace->channels[i].trans_channel_data;
1035 // int fd;
1036 //
1037 // if(!strcmp(trace->channels[i].channel_name, channel_name)) {
1038 // struct rchan_buf *rbuf = rchan->buf;
1039 // struct ltt_channel_buf_struct *lttbuf = trace->channels[i].buf;
1040 //
1041 // result = fd = ustcomm_app_detach_client(&ustcomm_app, src);
1042 // if(result == -1) {
1043 // ERR("ustcomm_app_detach_client failed");
1044 // goto next_cmd;
1045 // }
1046 //
1047 // lttbuf->wake_consumer_arg = (void *) fd;
1048 //
1049 // smp_wmb();
1050 //
1051 // lttbuf->call_wake_consumer = 1;
1052 //
1053 // break;
1054 // }
1055 // }
1056 //
1057 // free(channel_name);
1058 // }
1059 else {
1060 ERR("unable to parse message: %s", recvbuf);
1061 }
1062
1063 next_cmd:
1064
1065 return 0;
1066 }
1067
1068 void *listener_main(void *p)
1069 {
1070 int result;
1071
1072 DBG("LISTENER");
1073
1074 pthread_cleanup_push(listener_cleanup, NULL);
1075
1076 for(;;) {
1077 struct mpentries mpent;
1078
1079 multipoll_init(&mpent);
1080
1081 blocked_consumers_add_to_mp(&mpent);
1082 ustcomm_mp_add_app_clients(&mpent, &ustcomm_app, process_client_cmd);
1083
1084 result = multipoll_poll(&mpent, -1);
1085 if(result == -1) {
1086 ERR("error in multipoll_poll");
1087 }
1088
1089 multipoll_destroy(&mpent);
1090 }
1091
1092 pthread_cleanup_pop(1);
1093 }
1094
1095 /* These should only be accessed in the parent thread,
1096 * not the listener.
1097 */
1098 static volatile sig_atomic_t have_listener = 0;
1099 static pthread_t listener_thread;
1100
1101 void create_listener(void)
1102 {
1103 int result;
1104
1105 if(have_listener) {
1106 WARN("not creating listener because we already had one");
1107 return;
1108 }
1109
1110 result = pthread_create(&listener_thread, NULL, listener_main, NULL);
1111 if(result == -1) {
1112 PERROR("pthread_create");
1113 }
1114
1115 have_listener = 1;
1116 }
1117
1118 static int init_socket(void)
1119 {
1120 return ustcomm_init_app(getpid(), &ustcomm_app);
1121 }
1122
1123 #define AUTOPROBE_DISABLED 0
1124 #define AUTOPROBE_ENABLE_ALL 1
1125 #define AUTOPROBE_ENABLE_REGEX 2
1126 static int autoprobe_method = AUTOPROBE_DISABLED;
1127 static regex_t autoprobe_regex;
1128
1129 static void auto_probe_connect(struct marker *m)
1130 {
1131 int result;
1132
1133 char* concat_name = NULL;
1134 const char *probe_name = "default";
1135
1136 if(autoprobe_method == AUTOPROBE_DISABLED) {
1137 return;
1138 }
1139 else if(autoprobe_method == AUTOPROBE_ENABLE_REGEX) {
1140 result = asprintf(&concat_name, "%s/%s", m->channel, m->name);
1141 if(result == -1) {
1142 ERR("auto_probe_connect: asprintf failed (marker %s/%s)",
1143 m->channel, m->name);
1144 return;
1145 }
1146 if (regexec(&autoprobe_regex, concat_name, 0, NULL, 0)) {
1147 free(concat_name);
1148 return;
1149 }
1150 free(concat_name);
1151 }
1152
1153 result = ltt_marker_connect(m->channel, m->name, probe_name);
1154 if(result && result != -EEXIST)
1155 ERR("ltt_marker_connect (marker = %s/%s, errno = %d)", m->channel, m->name, -result);
1156
1157 DBG("auto connected marker %s (addr: %p) %s to probe default", m->channel, m, m->name);
1158
1159 }
1160
1161 static void __attribute__((constructor)) init()
1162 {
1163 int result;
1164 char* autoprobe_val = NULL;
1165
1166 /* Assign the pidunique, to be able to differentiate the processes with same
1167 * pid, (before and after an exec).
1168 */
1169 pidunique = make_pidunique();
1170
1171 DBG("Tracectl constructor");
1172
1173 result = init_socket();
1174 if(result == -1) {
1175 ERR("init_socket error");
1176 return;
1177 }
1178
1179 create_listener();
1180
1181 autoprobe_val = getenv("UST_AUTOPROBE");
1182 if(autoprobe_val) {
1183 struct marker_iter iter;
1184
1185 DBG("Autoprobe enabled.");
1186
1187 /* Ensure markers are initialized */
1188 //init_markers();
1189
1190 /* Ensure marker control is initialized, for the probe */
1191 init_marker_control();
1192
1193 /* first, set the callback that will connect the
1194 * probe on new markers
1195 */
1196 if(autoprobe_val[0] == '/') {
1197 result = regcomp(&autoprobe_regex, autoprobe_val+1, 0);
1198 if (result) {
1199 char regexerr[150];
1200
1201 regerror(result, &autoprobe_regex, regexerr, sizeof(regexerr));
1202 ERR("cannot parse regex %s (%s), will ignore UST_AUTOPROBE", autoprobe_val, regexerr);
1203 /* don't crash the application just for this */
1204 }
1205 else {
1206 autoprobe_method = AUTOPROBE_ENABLE_REGEX;
1207 }
1208 }
1209 else {
1210 /* just enable all instrumentation */
1211 autoprobe_method = AUTOPROBE_ENABLE_ALL;
1212 }
1213
1214 marker_set_new_marker_cb(auto_probe_connect);
1215
1216 /* Now, connect the probes that were already registered. */
1217 marker_iter_reset(&iter);
1218 marker_iter_start(&iter);
1219
1220 DBG("now iterating on markers already registered");
1221 while(iter.marker) {
1222 DBG("now iterating on marker %s", iter.marker->name);
1223 auto_probe_connect(iter.marker);
1224 marker_iter_next(&iter);
1225 }
1226 }
1227
1228 if(getenv("UST_TRACE")) {
1229 char trace_name[] = "auto";
1230 char trace_type[] = "ustrelay";
1231
1232 DBG("starting early tracing");
1233
1234 /* Ensure marker control is initialized */
1235 init_marker_control();
1236
1237 /* Ensure markers are initialized */
1238 init_markers();
1239
1240 /* Ensure buffers are initialized, for the transport to be available.
1241 * We are about to set a trace type and it will fail without this.
1242 */
1243 init_ustrelay_transport();
1244
1245 /* FIXME: When starting early tracing (here), depending on the
1246 * order of constructors, it is very well possible some marker
1247 * sections are not yet registered. Because of this, some
1248 * channels may not be registered. Yet, we are about to ask the
1249 * daemon to collect the channels. Channels which are not yet
1250 * registered will not be collected.
1251 *
1252 * Currently, in LTTng, there is no way to add a channel after
1253 * trace start. The reason for this is that it induces complex
1254 * concurrency issues on the trace structures, which can only
1255 * be resolved using RCU. This has not been done yet. As a
1256 * workaround, we are forcing the registration of the "ust"
1257 * channel here. This is the only channel (apart from metadata)
1258 * that can be reliably used in early tracing.
1259 *
1260 * Non-early tracing does not have this problem and can use
1261 * arbitrary channel names.
1262 */
1263 ltt_channels_register("ust");
1264
1265 result = ltt_trace_setup(trace_name);
1266 if(result < 0) {
1267 ERR("ltt_trace_setup failed");
1268 return;
1269 }
1270
1271 result = ltt_trace_set_type(trace_name, trace_type);
1272 if(result < 0) {
1273 ERR("ltt_trace_set_type failed");
1274 return;
1275 }
1276
1277 result = ltt_trace_alloc(trace_name);
1278 if(result < 0) {
1279 ERR("ltt_trace_alloc failed");
1280 return;
1281 }
1282
1283 result = ltt_trace_start(trace_name);
1284 if(result < 0) {
1285 ERR("ltt_trace_start failed");
1286 return;
1287 }
1288
1289 /* Do this after the trace is started in order to avoid creating confusion
1290 * if the trace fails to start. */
1291 inform_consumer_daemon(trace_name);
1292 }
1293
1294
1295 return;
1296
1297 /* should decrementally destroy stuff if error */
1298
1299 }
1300
1301 /* This is only called if we terminate normally, not with an unhandled signal,
1302 * so we cannot rely on it. However, for now, LTTV requires that the header of
1303 * the last sub-buffer contain a valid end time for the trace. This is done
1304 * automatically only when the trace is properly stopped.
1305 *
1306 * If the traced program crashed, it is always possible to manually add the
1307 * right value in the header, or to open the trace in text mode.
1308 *
1309 * FIXME: Fix LTTV so it doesn't need this.
1310 */
1311
1312 static void destroy_traces(void)
1313 {
1314 int result;
1315
1316 /* if trace running, finish it */
1317
1318 DBG("destructor stopping traces");
1319
1320 result = ltt_trace_stop("auto");
1321 if(result == -1) {
1322 ERR("ltt_trace_stop error");
1323 }
1324
1325 result = ltt_trace_destroy("auto", 0);
1326 if(result == -1) {
1327 ERR("ltt_trace_destroy error");
1328 }
1329 }
1330
1331 static int trace_recording(void)
1332 {
1333 int retval = 0;
1334 struct ust_trace *trace;
1335
1336 ltt_lock_traces();
1337
1338 list_for_each_entry(trace, &ltt_traces.head, list) {
1339 if(trace->active) {
1340 retval = 1;
1341 break;
1342 }
1343 }
1344
1345 ltt_unlock_traces();
1346
1347 return retval;
1348 }
1349
1350 #if 0
1351 static int have_consumer(void)
1352 {
1353 return !list_empty(&blocked_consumers);
1354 }
1355 #endif
1356
1357 int restarting_usleep(useconds_t usecs)
1358 {
1359 struct timespec tv;
1360 int result;
1361
1362 tv.tv_sec = 0;
1363 tv.tv_nsec = usecs * 1000;
1364
1365 do {
1366 result = nanosleep(&tv, &tv);
1367 } while(result == -1 && errno == EINTR);
1368
1369 return result;
1370 }
1371
1372 static void stop_listener()
1373 {
1374 int result;
1375
1376 result = pthread_cancel(listener_thread);
1377 if(result == -1) {
1378 PERROR("pthread_cancel");
1379 }
1380 result = pthread_join(listener_thread, NULL);
1381 if(result == -1) {
1382 PERROR("pthread_join");
1383 }
1384 }
1385
1386 /* This destructor keeps the process alive for a few seconds in order
1387 * to leave time to ustd to connect to its buffers. This is necessary
1388 * for programs whose execution is very short. It is also useful in all
1389 * programs when tracing is started close to the end of the program
1390 * execution.
1391 *
1392 * FIXME: For now, this only works for the first trace created in a
1393 * process.
1394 */
1395
1396 static void __attribute__((destructor)) keepalive()
1397 {
1398 if(trace_recording() && buffers_to_export) {
1399 int total = 0;
1400 DBG("Keeping process alive for consumer daemon...");
1401 while(buffers_to_export) {
1402 const int interv = 200000;
1403 restarting_usleep(interv);
1404 total += interv;
1405
1406 if(total >= 3000000) {
1407 WARN("non-consumed buffers remaining after wait limit; not waiting anymore");
1408 break;
1409 }
1410 }
1411 DBG("Finally dying...");
1412 }
1413
1414 destroy_traces();
1415
1416 /* Ask the listener to stop and clean up. */
1417 stop_listener();
1418 }
1419
1420 void ust_potential_exec(void)
1421 {
1422 trace_mark(ust, potential_exec, MARK_NOARGS);
1423
1424 DBG("test");
1425
1426 keepalive();
1427 }
1428
1429 /* Notify ust that there was a fork. This needs to be called inside
1430 * the new process, anytime a process whose memory is not shared with
1431 * the parent is created. If this function is not called, the events
1432 * of the new process will not be collected.
1433 *
1434 * Signals should be disabled before the fork and reenabled only after
1435 * this call in order to guarantee tracing is not started before ust_fork()
1436 * sanitizes the new process.
1437 */
1438
1439 static void ust_fork(void)
1440 {
1441 struct blocked_consumer *bc;
1442 struct blocked_consumer *deletable_bc = NULL;
1443 int result;
1444
1445 /* FIXME: technically, the locks could have been taken before the fork */
1446 DBG("ust: forking");
1447
1448 /* break lock if necessary */
1449 ltt_unlock_traces();
1450
1451 ltt_trace_stop("auto");
1452 ltt_trace_destroy("auto", 1);
1453 /* Delete all active connections */
1454 ustcomm_close_all_connections(&ustcomm_app.server);
1455
1456 /* Delete all blocked consumers */
1457 list_for_each_entry(bc, &blocked_consumers, list) {
1458 result = close(bc->fd_producer);
1459 if(result == -1) {
1460 PERROR("close");
1461 }
1462 free(deletable_bc);
1463 deletable_bc = bc;
1464 list_del(&bc->list);
1465 }
1466
1467 /* free app, keeping socket file */
1468 ustcomm_fini_app(&ustcomm_app, 1);
1469
1470 buffers_to_export = 0;
1471 have_listener = 0;
1472 init_socket();
1473 create_listener();
1474 ltt_trace_setup("auto");
1475 result = ltt_trace_set_type("auto", "ustrelay");
1476 if(result < 0) {
1477 ERR("ltt_trace_set_type failed");
1478 return;
1479 }
1480
1481 ltt_trace_alloc("auto");
1482 ltt_trace_start("auto");
1483 inform_consumer_daemon("auto");
1484 }
1485
1486 void ust_before_fork(ust_fork_info_t *fork_info)
1487 {
1488 /* Disable signals. This is to avoid that the child
1489 * intervenes before it is properly setup for tracing. It is
1490 * safer to disable all signals, because then we know we are not
1491 * breaking anything by restoring the original mask.
1492 */
1493 sigset_t all_sigs;
1494 int result;
1495
1496 /* FIXME:
1497 - only do this if tracing is active
1498 */
1499
1500 /* Disable signals */
1501 sigfillset(&all_sigs);
1502 result = sigprocmask(SIG_BLOCK, &all_sigs, &fork_info->orig_sigs);
1503 if(result == -1) {
1504 PERROR("sigprocmask");
1505 return;
1506 }
1507 }
1508
1509 /* Don't call this function directly in a traced program */
1510 static void ust_after_fork_common(ust_fork_info_t *fork_info)
1511 {
1512 int result;
1513
1514 /* Restore signals */
1515 result = sigprocmask(SIG_SETMASK, &fork_info->orig_sigs, NULL);
1516 if(result == -1) {
1517 PERROR("sigprocmask");
1518 return;
1519 }
1520 }
1521
1522 void ust_after_fork_parent(ust_fork_info_t *fork_info)
1523 {
1524 /* Reenable signals */
1525 ust_after_fork_common(fork_info);
1526 }
1527
1528 void ust_after_fork_child(ust_fork_info_t *fork_info)
1529 {
1530 /* First sanitize the child */
1531 ust_fork();
1532
1533 /* Then reenable interrupts */
1534 ust_after_fork_common(fork_info);
1535 }
1536
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