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Support flight recorder mode for a session
[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c
1 /*
2 * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License, version 2 only, as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
11 * more details.
12 *
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 51
15 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
16 */
17
18 #define _GNU_SOURCE
19 #include <assert.h>
20 #include <inttypes.h>
21 #include <urcu/list.h>
22 #include <urcu/uatomic.h>
23
24 #include <common/defaults.h>
25 #include <common/common.h>
26 #include <common/sessiond-comm/sessiond-comm.h>
27 #include <common/relayd/relayd.h>
28
29 #include "channel.h"
30 #include "consumer.h"
31 #include "event.h"
32 #include "health.h"
33 #include "kernel.h"
34 #include "kernel-consumer.h"
35 #include "lttng-sessiond.h"
36 #include "utils.h"
37
38 #include "cmd.h"
39
40 /*
41 * Used to keep a unique index for each relayd socket created where this value
42 * is associated with streams on the consumer so it can match the right relayd
43 * to send to. It must be accessed with the relayd_net_seq_idx_lock
44 * held.
45 */
46 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
47 static uint64_t relayd_net_seq_idx;
48
49 /*
50 * Create a session path used by list_lttng_sessions for the case that the
51 * session consumer is on the network.
52 */
53 static int build_network_session_path(char *dst, size_t size,
54 struct ltt_session *session)
55 {
56 int ret, kdata_port, udata_port;
57 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
58 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
59
60 assert(session);
61 assert(dst);
62
63 memset(tmp_urls, 0, sizeof(tmp_urls));
64 memset(tmp_uurl, 0, sizeof(tmp_uurl));
65
66 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
67
68 if (session->kernel_session && session->kernel_session->consumer) {
69 kuri = &session->kernel_session->consumer->dst.net.control;
70 kdata_port = session->kernel_session->consumer->dst.net.data.port;
71 }
72
73 if (session->ust_session && session->ust_session->consumer) {
74 uuri = &session->ust_session->consumer->dst.net.control;
75 udata_port = session->ust_session->consumer->dst.net.data.port;
76 }
77
78 if (uuri == NULL && kuri == NULL) {
79 uri = &session->consumer->dst.net.control;
80 kdata_port = session->consumer->dst.net.data.port;
81 } else if (kuri && uuri) {
82 ret = uri_compare(kuri, uuri);
83 if (ret) {
84 /* Not Equal */
85 uri = kuri;
86 /* Build uuri URL string */
87 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
88 if (ret < 0) {
89 goto error;
90 }
91 } else {
92 uri = kuri;
93 }
94 } else if (kuri && uuri == NULL) {
95 uri = kuri;
96 } else if (uuri && kuri == NULL) {
97 uri = uuri;
98 }
99
100 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
101 if (ret < 0) {
102 goto error;
103 }
104
105 /*
106 * Do we have a UST url set. If yes, this means we have both kernel and UST
107 * to print.
108 */
109 if (*tmp_uurl != '\0') {
110 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
111 tmp_urls, kdata_port, tmp_uurl, udata_port);
112 } else {
113 int dport;
114 if (kuri || (!kuri && !uuri)) {
115 dport = kdata_port;
116 } else {
117 /* No kernel URI, use the UST port. */
118 dport = udata_port;
119 }
120 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
121 }
122
123 error:
124 return ret;
125 }
126
127 /*
128 * Fill lttng_channel array of all channels.
129 */
130 static void list_lttng_channels(int domain, struct ltt_session *session,
131 struct lttng_channel *channels)
132 {
133 int i = 0;
134 struct ltt_kernel_channel *kchan;
135
136 DBG("Listing channels for session %s", session->name);
137
138 switch (domain) {
139 case LTTNG_DOMAIN_KERNEL:
140 /* Kernel channels */
141 if (session->kernel_session != NULL) {
142 cds_list_for_each_entry(kchan,
143 &session->kernel_session->channel_list.head, list) {
144 /* Copy lttng_channel struct to array */
145 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
146 channels[i].enabled = kchan->enabled;
147 i++;
148 }
149 }
150 break;
151 case LTTNG_DOMAIN_UST:
152 {
153 struct lttng_ht_iter iter;
154 struct ltt_ust_channel *uchan;
155
156 rcu_read_lock();
157 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
158 &iter.iter, uchan, node.node) {
159 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
160 channels[i].attr.overwrite = uchan->attr.overwrite;
161 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
162 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
163 channels[i].attr.switch_timer_interval =
164 uchan->attr.switch_timer_interval;
165 channels[i].attr.read_timer_interval =
166 uchan->attr.read_timer_interval;
167 channels[i].enabled = uchan->enabled;
168 switch (uchan->attr.output) {
169 case LTTNG_UST_MMAP:
170 default:
171 channels[i].attr.output = LTTNG_EVENT_MMAP;
172 break;
173 }
174 i++;
175 }
176 rcu_read_unlock();
177 break;
178 }
179 default:
180 break;
181 }
182 }
183
184 /*
185 * Create a list of ust global domain events.
186 */
187 static int list_lttng_ust_global_events(char *channel_name,
188 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
189 {
190 int i = 0, ret = 0;
191 unsigned int nb_event = 0;
192 struct lttng_ht_iter iter;
193 struct lttng_ht_node_str *node;
194 struct ltt_ust_channel *uchan;
195 struct ltt_ust_event *uevent;
196 struct lttng_event *tmp;
197
198 DBG("Listing UST global events for channel %s", channel_name);
199
200 rcu_read_lock();
201
202 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
203 node = lttng_ht_iter_get_node_str(&iter);
204 if (node == NULL) {
205 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
206 goto error;
207 }
208
209 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
210
211 nb_event += lttng_ht_get_count(uchan->events);
212
213 if (nb_event == 0) {
214 ret = nb_event;
215 goto error;
216 }
217
218 DBG3("Listing UST global %d events", nb_event);
219
220 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
221 if (tmp == NULL) {
222 ret = LTTNG_ERR_FATAL;
223 goto error;
224 }
225
226 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
227 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
228 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
229 tmp[i].enabled = uevent->enabled;
230
231 switch (uevent->attr.instrumentation) {
232 case LTTNG_UST_TRACEPOINT:
233 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
234 break;
235 case LTTNG_UST_PROBE:
236 tmp[i].type = LTTNG_EVENT_PROBE;
237 break;
238 case LTTNG_UST_FUNCTION:
239 tmp[i].type = LTTNG_EVENT_FUNCTION;
240 break;
241 }
242
243 tmp[i].loglevel = uevent->attr.loglevel;
244 switch (uevent->attr.loglevel_type) {
245 case LTTNG_UST_LOGLEVEL_ALL:
246 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
247 break;
248 case LTTNG_UST_LOGLEVEL_RANGE:
249 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
250 break;
251 case LTTNG_UST_LOGLEVEL_SINGLE:
252 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
253 break;
254 }
255 if (uevent->filter) {
256 tmp[i].filter = 1;
257 }
258 i++;
259 }
260
261 ret = nb_event;
262 *events = tmp;
263
264 error:
265 rcu_read_unlock();
266 return ret;
267 }
268
269 /*
270 * Fill lttng_event array of all kernel events in the channel.
271 */
272 static int list_lttng_kernel_events(char *channel_name,
273 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
274 {
275 int i = 0, ret;
276 unsigned int nb_event;
277 struct ltt_kernel_event *event;
278 struct ltt_kernel_channel *kchan;
279
280 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
281 if (kchan == NULL) {
282 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
283 goto error;
284 }
285
286 nb_event = kchan->event_count;
287
288 DBG("Listing events for channel %s", kchan->channel->name);
289
290 if (nb_event == 0) {
291 goto end;
292 }
293
294 *events = zmalloc(nb_event * sizeof(struct lttng_event));
295 if (*events == NULL) {
296 ret = LTTNG_ERR_FATAL;
297 goto error;
298 }
299
300 /* Kernel channels */
301 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
302 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
303 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
304 (*events)[i].enabled = event->enabled;
305
306 switch (event->event->instrumentation) {
307 case LTTNG_KERNEL_TRACEPOINT:
308 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
309 break;
310 case LTTNG_KERNEL_KRETPROBE:
311 (*events)[i].type = LTTNG_EVENT_FUNCTION;
312 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
313 sizeof(struct lttng_kernel_kprobe));
314 break;
315 case LTTNG_KERNEL_KPROBE:
316 (*events)[i].type = LTTNG_EVENT_PROBE;
317 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
318 sizeof(struct lttng_kernel_kprobe));
319 break;
320 case LTTNG_KERNEL_FUNCTION:
321 (*events)[i].type = LTTNG_EVENT_FUNCTION;
322 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
323 sizeof(struct lttng_kernel_function));
324 break;
325 case LTTNG_KERNEL_NOOP:
326 (*events)[i].type = LTTNG_EVENT_NOOP;
327 break;
328 case LTTNG_KERNEL_SYSCALL:
329 (*events)[i].type = LTTNG_EVENT_SYSCALL;
330 break;
331 case LTTNG_KERNEL_ALL:
332 assert(0);
333 break;
334 }
335 i++;
336 }
337
338 end:
339 return nb_event;
340
341 error:
342 /* Negate the error code to differentiate the size from an error */
343 return -ret;
344 }
345
346 /*
347 * Add URI so the consumer output object. Set the correct path depending on the
348 * domain adding the default trace directory.
349 */
350 static int add_uri_to_consumer(struct consumer_output *consumer,
351 struct lttng_uri *uri, int domain, const char *session_name)
352 {
353 int ret = LTTNG_OK;
354 const char *default_trace_dir;
355
356 assert(uri);
357
358 if (consumer == NULL) {
359 DBG("No consumer detected. Don't add URI. Stopping.");
360 ret = LTTNG_ERR_NO_CONSUMER;
361 goto error;
362 }
363
364 switch (domain) {
365 case LTTNG_DOMAIN_KERNEL:
366 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
367 break;
368 case LTTNG_DOMAIN_UST:
369 default_trace_dir = DEFAULT_UST_TRACE_DIR;
370 break;
371 default:
372 /*
373 * This case is possible is we try to add the URI to the global tracing
374 * session consumer object which in this case there is no subdir.
375 */
376 default_trace_dir = "";
377 }
378
379 switch (uri->dtype) {
380 case LTTNG_DST_IPV4:
381 case LTTNG_DST_IPV6:
382 DBG2("Setting network URI to consumer");
383
384 if (consumer->type == CONSUMER_DST_NET) {
385 if ((uri->stype == LTTNG_STREAM_CONTROL &&
386 consumer->dst.net.control_isset) ||
387 (uri->stype == LTTNG_STREAM_DATA &&
388 consumer->dst.net.data_isset)) {
389 ret = LTTNG_ERR_URL_EXIST;
390 goto error;
391 }
392 } else {
393 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
394 }
395
396 consumer->type = CONSUMER_DST_NET;
397
398 /* Set URI into consumer output object */
399 ret = consumer_set_network_uri(consumer, uri);
400 if (ret < 0) {
401 ret = -ret;
402 goto error;
403 } else if (ret == 1) {
404 /*
405 * URI was the same in the consumer so we do not append the subdir
406 * again so to not duplicate output dir.
407 */
408 goto error;
409 }
410
411 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
412 ret = consumer_set_subdir(consumer, session_name);
413 if (ret < 0) {
414 ret = LTTNG_ERR_FATAL;
415 goto error;
416 }
417 }
418
419 if (uri->stype == LTTNG_STREAM_CONTROL) {
420 /* On a new subdir, reappend the default trace dir. */
421 strncat(consumer->subdir, default_trace_dir,
422 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
423 DBG3("Append domain trace name to subdir %s", consumer->subdir);
424 }
425
426 break;
427 case LTTNG_DST_PATH:
428 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
429 memset(consumer->dst.trace_path, 0,
430 sizeof(consumer->dst.trace_path));
431 strncpy(consumer->dst.trace_path, uri->dst.path,
432 sizeof(consumer->dst.trace_path));
433 /* Append default trace dir */
434 strncat(consumer->dst.trace_path, default_trace_dir,
435 sizeof(consumer->dst.trace_path) -
436 strlen(consumer->dst.trace_path) - 1);
437 /* Flag consumer as local. */
438 consumer->type = CONSUMER_DST_LOCAL;
439 break;
440 }
441
442 ret = LTTNG_OK;
443
444 error:
445 return ret;
446 }
447
448 /*
449 * Init tracing by creating trace directory and sending fds kernel consumer.
450 */
451 static int init_kernel_tracing(struct ltt_kernel_session *session)
452 {
453 int ret = 0;
454 struct lttng_ht_iter iter;
455 struct consumer_socket *socket;
456
457 assert(session);
458
459 rcu_read_lock();
460
461 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
462 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
463 socket, node.node) {
464 /* Code flow error */
465 assert(socket->fd >= 0);
466
467 pthread_mutex_lock(socket->lock);
468 ret = kernel_consumer_send_session(socket, session);
469 pthread_mutex_unlock(socket->lock);
470 if (ret < 0) {
471 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
472 goto error;
473 }
474 }
475 }
476
477 error:
478 rcu_read_unlock();
479 return ret;
480 }
481
482 /*
483 * Create a socket to the relayd using the URI.
484 *
485 * On success, the relayd_sock pointer is set to the created socket.
486 * Else, it's stays untouched and a lttcomm error code is returned.
487 */
488 static int create_connect_relayd(struct lttng_uri *uri,
489 struct lttcomm_relayd_sock **relayd_sock)
490 {
491 int ret;
492 struct lttcomm_relayd_sock *rsock;
493
494 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
495 RELAYD_VERSION_COMM_MINOR);
496 if (!rsock) {
497 ret = LTTNG_ERR_FATAL;
498 goto error;
499 }
500
501 /*
502 * Connect to relayd so we can proceed with a session creation. This call
503 * can possibly block for an arbitrary amount of time to set the health
504 * state to be in poll execution.
505 */
506 health_poll_entry();
507 ret = relayd_connect(rsock);
508 health_poll_exit();
509 if (ret < 0) {
510 ERR("Unable to reach lttng-relayd");
511 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
512 goto free_sock;
513 }
514
515 /* Create socket for control stream. */
516 if (uri->stype == LTTNG_STREAM_CONTROL) {
517 DBG3("Creating relayd stream socket from URI");
518
519 /* Check relayd version */
520 ret = relayd_version_check(rsock);
521 if (ret < 0) {
522 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
523 goto close_sock;
524 }
525 } else if (uri->stype == LTTNG_STREAM_DATA) {
526 DBG3("Creating relayd data socket from URI");
527 } else {
528 /* Command is not valid */
529 ERR("Relayd invalid stream type: %d", uri->stype);
530 ret = LTTNG_ERR_INVALID;
531 goto close_sock;
532 }
533
534 *relayd_sock = rsock;
535
536 return LTTNG_OK;
537
538 close_sock:
539 /* The returned value is not useful since we are on an error path. */
540 (void) relayd_close(rsock);
541 free_sock:
542 free(rsock);
543 error:
544 return ret;
545 }
546
547 /*
548 * Connect to the relayd using URI and send the socket to the right consumer.
549 */
550 static int send_consumer_relayd_socket(int domain, unsigned int session_id,
551 struct lttng_uri *relayd_uri, struct consumer_output *consumer,
552 struct consumer_socket *consumer_sock)
553 {
554 int ret;
555 struct lttcomm_relayd_sock *rsock = NULL;
556
557 /* Connect to relayd and make version check if uri is the control. */
558 ret = create_connect_relayd(relayd_uri, &rsock);
559 if (ret != LTTNG_OK) {
560 goto error;
561 }
562 assert(rsock);
563
564 /* Set the network sequence index if not set. */
565 if (consumer->net_seq_index == (uint64_t) -1ULL) {
566 pthread_mutex_lock(&relayd_net_seq_idx_lock);
567 /*
568 * Increment net_seq_idx because we are about to transfer the
569 * new relayd socket to the consumer.
570 * Assign unique key so the consumer can match streams.
571 */
572 consumer->net_seq_index = ++relayd_net_seq_idx;
573 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
574 }
575
576 /* Send relayd socket to consumer. */
577 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
578 relayd_uri->stype, session_id);
579 if (ret < 0) {
580 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
581 goto close_sock;
582 }
583
584 /* Flag that the corresponding socket was sent. */
585 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
586 consumer_sock->control_sock_sent = 1;
587 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
588 consumer_sock->data_sock_sent = 1;
589 }
590
591 ret = LTTNG_OK;
592
593 /*
594 * Close socket which was dup on the consumer side. The session daemon does
595 * NOT keep track of the relayd socket(s) once transfer to the consumer.
596 */
597
598 close_sock:
599 (void) relayd_close(rsock);
600 free(rsock);
601
602 error:
603 if (ret != LTTNG_OK) {
604 /*
605 * The consumer output for this session should not be used anymore
606 * since the relayd connection failed thus making any tracing or/and
607 * streaming not usable.
608 */
609 consumer->enabled = 0;
610 }
611 return ret;
612 }
613
614 /*
615 * Send both relayd sockets to a specific consumer and domain. This is a
616 * helper function to facilitate sending the information to the consumer for a
617 * session.
618 */
619 static int send_consumer_relayd_sockets(int domain, unsigned int session_id,
620 struct consumer_output *consumer, struct consumer_socket *sock)
621 {
622 int ret = LTTNG_OK;
623
624 assert(consumer);
625 assert(sock);
626
627 /* Sending control relayd socket. */
628 if (!sock->control_sock_sent) {
629 ret = send_consumer_relayd_socket(domain, session_id,
630 &consumer->dst.net.control, consumer, sock);
631 if (ret != LTTNG_OK) {
632 goto error;
633 }
634 }
635
636 /* Sending data relayd socket. */
637 if (!sock->data_sock_sent) {
638 ret = send_consumer_relayd_socket(domain, session_id,
639 &consumer->dst.net.data, consumer, sock);
640 if (ret != LTTNG_OK) {
641 goto error;
642 }
643 }
644
645 error:
646 return ret;
647 }
648
649 /*
650 * Setup relayd connections for a tracing session. First creates the socket to
651 * the relayd and send them to the right domain consumer. Consumer type MUST be
652 * network.
653 */
654 int cmd_setup_relayd(struct ltt_session *session)
655 {
656 int ret = LTTNG_OK;
657 struct ltt_ust_session *usess;
658 struct ltt_kernel_session *ksess;
659 struct consumer_socket *socket;
660 struct lttng_ht_iter iter;
661
662 assert(session);
663
664 usess = session->ust_session;
665 ksess = session->kernel_session;
666
667 DBG("Setting relayd for session %s", session->name);
668
669 rcu_read_lock();
670
671 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
672 && usess->consumer->enabled) {
673 /* For each consumer socket, send relayd sockets */
674 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
675 socket, node.node) {
676 /* Code flow error */
677 assert(socket->fd >= 0);
678
679 pthread_mutex_lock(socket->lock);
680 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
681 usess->consumer, socket);
682 pthread_mutex_unlock(socket->lock);
683 if (ret != LTTNG_OK) {
684 goto error;
685 }
686 /* Session is now ready for network streaming. */
687 session->net_handle = 1;
688 }
689 }
690
691 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
692 && ksess->consumer->enabled) {
693 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
694 socket, node.node) {
695 /* Code flow error */
696 assert(socket->fd >= 0);
697
698 pthread_mutex_lock(socket->lock);
699 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
700 ksess->consumer, socket);
701 pthread_mutex_unlock(socket->lock);
702 if (ret != LTTNG_OK) {
703 goto error;
704 }
705 /* Session is now ready for network streaming. */
706 session->net_handle = 1;
707 }
708 }
709
710 error:
711 rcu_read_unlock();
712 return ret;
713 }
714
715 /*
716 * Start a kernel session by opening all necessary streams.
717 */
718 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
719 {
720 int ret;
721 struct ltt_kernel_channel *kchan;
722
723 /* Open kernel metadata */
724 if (ksess->metadata == NULL) {
725 ret = kernel_open_metadata(ksess);
726 if (ret < 0) {
727 ret = LTTNG_ERR_KERN_META_FAIL;
728 goto error;
729 }
730 }
731
732 /* Open kernel metadata stream */
733 if (ksess->metadata_stream_fd < 0) {
734 ret = kernel_open_metadata_stream(ksess);
735 if (ret < 0) {
736 ERR("Kernel create metadata stream failed");
737 ret = LTTNG_ERR_KERN_STREAM_FAIL;
738 goto error;
739 }
740 }
741
742 /* For each channel */
743 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
744 if (kchan->stream_count == 0) {
745 ret = kernel_open_channel_stream(kchan);
746 if (ret < 0) {
747 ret = LTTNG_ERR_KERN_STREAM_FAIL;
748 goto error;
749 }
750 /* Update the stream global counter */
751 ksess->stream_count_global += ret;
752 }
753 }
754
755 /* Setup kernel consumer socket and send fds to it */
756 ret = init_kernel_tracing(ksess);
757 if (ret != 0) {
758 ret = LTTNG_ERR_KERN_START_FAIL;
759 goto error;
760 }
761
762 /* This start the kernel tracing */
763 ret = kernel_start_session(ksess);
764 if (ret < 0) {
765 ret = LTTNG_ERR_KERN_START_FAIL;
766 goto error;
767 }
768
769 /* Quiescent wait after starting trace */
770 kernel_wait_quiescent(kernel_tracer_fd);
771
772 ksess->started = 1;
773
774 ret = LTTNG_OK;
775
776 error:
777 return ret;
778 }
779
780 /*
781 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
782 */
783 int cmd_disable_channel(struct ltt_session *session, int domain,
784 char *channel_name)
785 {
786 int ret;
787 struct ltt_ust_session *usess;
788
789 usess = session->ust_session;
790
791 rcu_read_lock();
792
793 switch (domain) {
794 case LTTNG_DOMAIN_KERNEL:
795 {
796 ret = channel_kernel_disable(session->kernel_session,
797 channel_name);
798 if (ret != LTTNG_OK) {
799 goto error;
800 }
801
802 kernel_wait_quiescent(kernel_tracer_fd);
803 break;
804 }
805 case LTTNG_DOMAIN_UST:
806 {
807 struct ltt_ust_channel *uchan;
808 struct lttng_ht *chan_ht;
809
810 chan_ht = usess->domain_global.channels;
811
812 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
813 if (uchan == NULL) {
814 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
815 goto error;
816 }
817
818 ret = channel_ust_disable(usess, uchan);
819 if (ret != LTTNG_OK) {
820 goto error;
821 }
822 break;
823 }
824 #if 0
825 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
826 case LTTNG_DOMAIN_UST_EXEC_NAME:
827 case LTTNG_DOMAIN_UST_PID:
828 #endif
829 default:
830 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
831 goto error;
832 }
833
834 ret = LTTNG_OK;
835
836 error:
837 rcu_read_unlock();
838 return ret;
839 }
840
841 /*
842 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
843 *
844 * The wpipe arguments is used as a notifier for the kernel thread.
845 */
846 int cmd_enable_channel(struct ltt_session *session,
847 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
848 {
849 int ret;
850 struct ltt_ust_session *usess = session->ust_session;
851 struct lttng_ht *chan_ht;
852
853 assert(session);
854 assert(attr);
855 assert(domain);
856
857 DBG("Enabling channel %s for session %s", attr->name, session->name);
858
859 /*
860 * Don't try to enable a channel if the session has been started at
861 * some point in time before. The tracer does not allow it.
862 */
863 if (session->started) {
864 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
865 goto error;
866 }
867
868 rcu_read_lock();
869
870 switch (domain->type) {
871 case LTTNG_DOMAIN_KERNEL:
872 {
873 struct ltt_kernel_channel *kchan;
874
875 kchan = trace_kernel_get_channel_by_name(attr->name,
876 session->kernel_session);
877 if (kchan == NULL) {
878 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
879 } else {
880 ret = channel_kernel_enable(session->kernel_session, kchan);
881 }
882
883 if (ret != LTTNG_OK) {
884 goto error;
885 }
886
887 kernel_wait_quiescent(kernel_tracer_fd);
888 break;
889 }
890 case LTTNG_DOMAIN_UST:
891 {
892 struct ltt_ust_channel *uchan;
893
894 chan_ht = usess->domain_global.channels;
895
896 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
897 if (uchan == NULL) {
898 ret = channel_ust_create(usess, attr, domain->buf_type);
899 } else {
900 ret = channel_ust_enable(usess, uchan);
901 }
902 break;
903 }
904 default:
905 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
906 goto error;
907 }
908
909 error:
910 rcu_read_unlock();
911 return ret;
912 }
913
914
915 /*
916 * Command LTTNG_DISABLE_EVENT processed by the client thread.
917 */
918 int cmd_disable_event(struct ltt_session *session, int domain,
919 char *channel_name, char *event_name)
920 {
921 int ret;
922
923 rcu_read_lock();
924
925 switch (domain) {
926 case LTTNG_DOMAIN_KERNEL:
927 {
928 struct ltt_kernel_channel *kchan;
929 struct ltt_kernel_session *ksess;
930
931 ksess = session->kernel_session;
932
933 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
934 if (kchan == NULL) {
935 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
936 goto error;
937 }
938
939 ret = event_kernel_disable_tracepoint(kchan, event_name);
940 if (ret != LTTNG_OK) {
941 goto error;
942 }
943
944 kernel_wait_quiescent(kernel_tracer_fd);
945 break;
946 }
947 case LTTNG_DOMAIN_UST:
948 {
949 struct ltt_ust_channel *uchan;
950 struct ltt_ust_session *usess;
951
952 usess = session->ust_session;
953
954 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
955 channel_name);
956 if (uchan == NULL) {
957 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
958 goto error;
959 }
960
961 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
962 if (ret != LTTNG_OK) {
963 goto error;
964 }
965
966 DBG3("Disable UST event %s in channel %s completed", event_name,
967 channel_name);
968 break;
969 }
970 #if 0
971 case LTTNG_DOMAIN_UST_EXEC_NAME:
972 case LTTNG_DOMAIN_UST_PID:
973 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
974 #endif
975 default:
976 ret = LTTNG_ERR_UND;
977 goto error;
978 }
979
980 ret = LTTNG_OK;
981
982 error:
983 rcu_read_unlock();
984 return ret;
985 }
986
987 /*
988 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
989 */
990 int cmd_disable_event_all(struct ltt_session *session, int domain,
991 char *channel_name)
992 {
993 int ret;
994
995 rcu_read_lock();
996
997 switch (domain) {
998 case LTTNG_DOMAIN_KERNEL:
999 {
1000 struct ltt_kernel_session *ksess;
1001 struct ltt_kernel_channel *kchan;
1002
1003 ksess = session->kernel_session;
1004
1005 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1006 if (kchan == NULL) {
1007 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1008 goto error;
1009 }
1010
1011 ret = event_kernel_disable_all(kchan);
1012 if (ret != LTTNG_OK) {
1013 goto error;
1014 }
1015
1016 kernel_wait_quiescent(kernel_tracer_fd);
1017 break;
1018 }
1019 case LTTNG_DOMAIN_UST:
1020 {
1021 struct ltt_ust_session *usess;
1022 struct ltt_ust_channel *uchan;
1023
1024 usess = session->ust_session;
1025
1026 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1027 channel_name);
1028 if (uchan == NULL) {
1029 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1030 goto error;
1031 }
1032
1033 ret = event_ust_disable_all_tracepoints(usess, uchan);
1034 if (ret != 0) {
1035 goto error;
1036 }
1037
1038 DBG3("Disable all UST events in channel %s completed", channel_name);
1039
1040 break;
1041 }
1042 #if 0
1043 case LTTNG_DOMAIN_UST_EXEC_NAME:
1044 case LTTNG_DOMAIN_UST_PID:
1045 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1046 #endif
1047 default:
1048 ret = LTTNG_ERR_UND;
1049 goto error;
1050 }
1051
1052 ret = LTTNG_OK;
1053
1054 error:
1055 rcu_read_unlock();
1056 return ret;
1057 }
1058
1059 /*
1060 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1061 */
1062 int cmd_add_context(struct ltt_session *session, int domain,
1063 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1064 {
1065 int ret, chan_kern_created = 0, chan_ust_created = 0;
1066
1067 switch (domain) {
1068 case LTTNG_DOMAIN_KERNEL:
1069 assert(session->kernel_session);
1070
1071 if (session->kernel_session->channel_count == 0) {
1072 /* Create default channel */
1073 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1074 if (ret != LTTNG_OK) {
1075 goto error;
1076 }
1077 chan_kern_created = 1;
1078 }
1079
1080 /* Add kernel context to kernel tracer */
1081 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1082 if (ret != LTTNG_OK) {
1083 goto error;
1084 }
1085 break;
1086 case LTTNG_DOMAIN_UST:
1087 {
1088 struct ltt_ust_session *usess = session->ust_session;
1089 assert(usess);
1090
1091 unsigned int chan_count =
1092 lttng_ht_get_count(usess->domain_global.channels);
1093 if (chan_count == 0) {
1094 struct lttng_channel *attr;
1095 /* Create default channel */
1096 attr = channel_new_default_attr(domain, usess->buffer_type);
1097 if (attr == NULL) {
1098 ret = LTTNG_ERR_FATAL;
1099 goto error;
1100 }
1101
1102 ret = channel_ust_create(usess, attr, usess->buffer_type);
1103 if (ret != LTTNG_OK) {
1104 free(attr);
1105 goto error;
1106 }
1107 free(attr);
1108 chan_ust_created = 1;
1109 }
1110
1111 ret = context_ust_add(usess, domain, ctx, channel_name);
1112 if (ret != LTTNG_OK) {
1113 goto error;
1114 }
1115 break;
1116 }
1117 #if 0
1118 case LTTNG_DOMAIN_UST_EXEC_NAME:
1119 case LTTNG_DOMAIN_UST_PID:
1120 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1121 #endif
1122 default:
1123 ret = LTTNG_ERR_UND;
1124 goto error;
1125 }
1126
1127 return LTTNG_OK;
1128
1129 error:
1130 if (chan_kern_created) {
1131 struct ltt_kernel_channel *kchan =
1132 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1133 session->kernel_session);
1134 /* Created previously, this should NOT fail. */
1135 assert(kchan);
1136 kernel_destroy_channel(kchan);
1137 }
1138
1139 if (chan_ust_created) {
1140 struct ltt_ust_channel *uchan =
1141 trace_ust_find_channel_by_name(
1142 session->ust_session->domain_global.channels,
1143 DEFAULT_CHANNEL_NAME);
1144 /* Created previously, this should NOT fail. */
1145 assert(uchan);
1146 /* Remove from the channel list of the session. */
1147 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1148 uchan);
1149 trace_ust_destroy_channel(uchan);
1150 }
1151 return ret;
1152 }
1153
1154 /*
1155 * Command LTTNG_ENABLE_EVENT processed by the client thread.
1156 */
1157 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1158 char *channel_name, struct lttng_event *event,
1159 struct lttng_filter_bytecode *filter, int wpipe)
1160 {
1161 int ret, channel_created = 0;
1162 struct lttng_channel *attr;
1163
1164 assert(session);
1165 assert(event);
1166 assert(channel_name);
1167
1168 rcu_read_lock();
1169
1170 switch (domain->type) {
1171 case LTTNG_DOMAIN_KERNEL:
1172 {
1173 struct ltt_kernel_channel *kchan;
1174
1175 kchan = trace_kernel_get_channel_by_name(channel_name,
1176 session->kernel_session);
1177 if (kchan == NULL) {
1178 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1179 LTTNG_BUFFER_GLOBAL);
1180 if (attr == NULL) {
1181 ret = LTTNG_ERR_FATAL;
1182 goto error;
1183 }
1184 strncpy(attr->name, channel_name, sizeof(attr->name));
1185
1186 ret = cmd_enable_channel(session, domain, attr, wpipe);
1187 if (ret != LTTNG_OK) {
1188 free(attr);
1189 goto error;
1190 }
1191 free(attr);
1192
1193 channel_created = 1;
1194 }
1195
1196 /* Get the newly created kernel channel pointer */
1197 kchan = trace_kernel_get_channel_by_name(channel_name,
1198 session->kernel_session);
1199 if (kchan == NULL) {
1200 /* This sould not happen... */
1201 ret = LTTNG_ERR_FATAL;
1202 goto error;
1203 }
1204
1205 ret = event_kernel_enable_tracepoint(kchan, event);
1206 if (ret != LTTNG_OK) {
1207 if (channel_created) {
1208 /* Let's not leak a useless channel. */
1209 kernel_destroy_channel(kchan);
1210 }
1211 goto error;
1212 }
1213
1214 kernel_wait_quiescent(kernel_tracer_fd);
1215 break;
1216 }
1217 case LTTNG_DOMAIN_UST:
1218 {
1219 struct ltt_ust_channel *uchan;
1220 struct ltt_ust_session *usess = session->ust_session;
1221
1222 assert(usess);
1223
1224 /* Get channel from global UST domain */
1225 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1226 channel_name);
1227 if (uchan == NULL) {
1228 /* Create default channel */
1229 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1230 usess->buffer_type);
1231 if (attr == NULL) {
1232 ret = LTTNG_ERR_FATAL;
1233 goto error;
1234 }
1235 strncpy(attr->name, channel_name, sizeof(attr->name));
1236
1237 ret = cmd_enable_channel(session, domain, attr, wpipe);
1238 if (ret != LTTNG_OK) {
1239 free(attr);
1240 goto error;
1241 }
1242 free(attr);
1243
1244 /* Get the newly created channel reference back */
1245 uchan = trace_ust_find_channel_by_name(
1246 usess->domain_global.channels, channel_name);
1247 assert(uchan);
1248 }
1249
1250 /* At this point, the session and channel exist on the tracer */
1251 ret = event_ust_enable_tracepoint(usess, uchan, event, filter);
1252 if (ret != LTTNG_OK) {
1253 goto error;
1254 }
1255 break;
1256 }
1257 #if 0
1258 case LTTNG_DOMAIN_UST_EXEC_NAME:
1259 case LTTNG_DOMAIN_UST_PID:
1260 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1261 #endif
1262 default:
1263 ret = LTTNG_ERR_UND;
1264 goto error;
1265 }
1266
1267 ret = LTTNG_OK;
1268
1269 error:
1270 rcu_read_unlock();
1271 return ret;
1272 }
1273
1274 /*
1275 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
1276 */
1277 int cmd_enable_event_all(struct ltt_session *session,
1278 struct lttng_domain *domain, char *channel_name, int event_type,
1279 struct lttng_filter_bytecode *filter, int wpipe)
1280 {
1281 int ret;
1282 struct lttng_channel *attr;
1283
1284 assert(session);
1285 assert(channel_name);
1286
1287 rcu_read_lock();
1288
1289 switch (domain->type) {
1290 case LTTNG_DOMAIN_KERNEL:
1291 {
1292 struct ltt_kernel_channel *kchan;
1293
1294 assert(session->kernel_session);
1295
1296 kchan = trace_kernel_get_channel_by_name(channel_name,
1297 session->kernel_session);
1298 if (kchan == NULL) {
1299 /* Create default channel */
1300 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1301 LTTNG_BUFFER_GLOBAL);
1302 if (attr == NULL) {
1303 ret = LTTNG_ERR_FATAL;
1304 goto error;
1305 }
1306 strncpy(attr->name, channel_name, sizeof(attr->name));
1307
1308 ret = cmd_enable_channel(session, domain, attr, wpipe);
1309 if (ret != LTTNG_OK) {
1310 free(attr);
1311 goto error;
1312 }
1313 free(attr);
1314
1315 /* Get the newly created kernel channel pointer */
1316 kchan = trace_kernel_get_channel_by_name(channel_name,
1317 session->kernel_session);
1318 assert(kchan);
1319 }
1320
1321 switch (event_type) {
1322 case LTTNG_EVENT_SYSCALL:
1323 ret = event_kernel_enable_all_syscalls(kchan, kernel_tracer_fd);
1324 break;
1325 case LTTNG_EVENT_TRACEPOINT:
1326 /*
1327 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
1328 * events already registered to the channel.
1329 */
1330 ret = event_kernel_enable_all_tracepoints(kchan, kernel_tracer_fd);
1331 break;
1332 case LTTNG_EVENT_ALL:
1333 /* Enable syscalls and tracepoints */
1334 ret = event_kernel_enable_all(kchan, kernel_tracer_fd);
1335 break;
1336 default:
1337 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1338 goto error;
1339 }
1340
1341 /* Manage return value */
1342 if (ret != LTTNG_OK) {
1343 /*
1344 * On error, cmd_enable_channel call will take care of destroying
1345 * the created channel if it was needed.
1346 */
1347 goto error;
1348 }
1349
1350 kernel_wait_quiescent(kernel_tracer_fd);
1351 break;
1352 }
1353 case LTTNG_DOMAIN_UST:
1354 {
1355 struct ltt_ust_channel *uchan;
1356 struct ltt_ust_session *usess = session->ust_session;
1357
1358 assert(usess);
1359
1360 /* Get channel from global UST domain */
1361 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1362 channel_name);
1363 if (uchan == NULL) {
1364 /* Create default channel */
1365 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1366 usess->buffer_type);
1367 if (attr == NULL) {
1368 ret = LTTNG_ERR_FATAL;
1369 goto error;
1370 }
1371 strncpy(attr->name, channel_name, sizeof(attr->name));
1372
1373 ret = cmd_enable_channel(session, domain, attr, wpipe);
1374 if (ret != LTTNG_OK) {
1375 free(attr);
1376 goto error;
1377 }
1378 free(attr);
1379
1380 /* Get the newly created channel reference back */
1381 uchan = trace_ust_find_channel_by_name(
1382 usess->domain_global.channels, channel_name);
1383 assert(uchan);
1384 }
1385
1386 /* At this point, the session and channel exist on the tracer */
1387
1388 switch (event_type) {
1389 case LTTNG_EVENT_ALL:
1390 case LTTNG_EVENT_TRACEPOINT:
1391 ret = event_ust_enable_all_tracepoints(usess, uchan, filter);
1392 if (ret != LTTNG_OK) {
1393 goto error;
1394 }
1395 break;
1396 default:
1397 ret = LTTNG_ERR_UST_ENABLE_FAIL;
1398 goto error;
1399 }
1400
1401 /* Manage return value */
1402 if (ret != LTTNG_OK) {
1403 goto error;
1404 }
1405
1406 break;
1407 }
1408 #if 0
1409 case LTTNG_DOMAIN_UST_EXEC_NAME:
1410 case LTTNG_DOMAIN_UST_PID:
1411 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1412 #endif
1413 default:
1414 ret = LTTNG_ERR_UND;
1415 goto error;
1416 }
1417
1418 ret = LTTNG_OK;
1419
1420 error:
1421 rcu_read_unlock();
1422 return ret;
1423 }
1424
1425
1426 /*
1427 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1428 */
1429 ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
1430 {
1431 int ret;
1432 ssize_t nb_events = 0;
1433
1434 switch (domain) {
1435 case LTTNG_DOMAIN_KERNEL:
1436 nb_events = kernel_list_events(kernel_tracer_fd, events);
1437 if (nb_events < 0) {
1438 ret = LTTNG_ERR_KERN_LIST_FAIL;
1439 goto error;
1440 }
1441 break;
1442 case LTTNG_DOMAIN_UST:
1443 nb_events = ust_app_list_events(events);
1444 if (nb_events < 0) {
1445 ret = LTTNG_ERR_UST_LIST_FAIL;
1446 goto error;
1447 }
1448 break;
1449 default:
1450 ret = LTTNG_ERR_UND;
1451 goto error;
1452 }
1453
1454 return nb_events;
1455
1456 error:
1457 /* Return negative value to differentiate return code */
1458 return -ret;
1459 }
1460
1461 /*
1462 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1463 */
1464 ssize_t cmd_list_tracepoint_fields(int domain,
1465 struct lttng_event_field **fields)
1466 {
1467 int ret;
1468 ssize_t nb_fields = 0;
1469
1470 switch (domain) {
1471 case LTTNG_DOMAIN_UST:
1472 nb_fields = ust_app_list_event_fields(fields);
1473 if (nb_fields < 0) {
1474 ret = LTTNG_ERR_UST_LIST_FAIL;
1475 goto error;
1476 }
1477 break;
1478 case LTTNG_DOMAIN_KERNEL:
1479 default: /* fall-through */
1480 ret = LTTNG_ERR_UND;
1481 goto error;
1482 }
1483
1484 return nb_fields;
1485
1486 error:
1487 /* Return negative value to differentiate return code */
1488 return -ret;
1489 }
1490
1491 /*
1492 * Command LTTNG_START_TRACE processed by the client thread.
1493 */
1494 int cmd_start_trace(struct ltt_session *session)
1495 {
1496 int ret;
1497 struct ltt_kernel_session *ksession;
1498 struct ltt_ust_session *usess;
1499
1500 assert(session);
1501
1502 /* Ease our life a bit ;) */
1503 ksession = session->kernel_session;
1504 usess = session->ust_session;
1505
1506 if (session->enabled) {
1507 /* Already started. */
1508 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1509 goto error;
1510 }
1511
1512 session->enabled = 1;
1513
1514 /* Kernel tracing */
1515 if (ksession != NULL) {
1516 ret = start_kernel_session(ksession, kernel_tracer_fd);
1517 if (ret != LTTNG_OK) {
1518 goto error;
1519 }
1520 }
1521
1522 /* Flag session that trace should start automatically */
1523 if (usess) {
1524 usess->start_trace = 1;
1525
1526 ret = ust_app_start_trace_all(usess);
1527 if (ret < 0) {
1528 ret = LTTNG_ERR_UST_START_FAIL;
1529 goto error;
1530 }
1531 }
1532
1533 session->started = 1;
1534
1535 ret = LTTNG_OK;
1536
1537 error:
1538 return ret;
1539 }
1540
1541 /*
1542 * Command LTTNG_STOP_TRACE processed by the client thread.
1543 */
1544 int cmd_stop_trace(struct ltt_session *session)
1545 {
1546 int ret;
1547 struct ltt_kernel_channel *kchan;
1548 struct ltt_kernel_session *ksession;
1549 struct ltt_ust_session *usess;
1550
1551 assert(session);
1552
1553 /* Short cut */
1554 ksession = session->kernel_session;
1555 usess = session->ust_session;
1556
1557 if (!session->enabled) {
1558 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
1559 goto error;
1560 }
1561
1562 session->enabled = 0;
1563
1564 /* Kernel tracer */
1565 if (ksession && ksession->started) {
1566 DBG("Stop kernel tracing");
1567
1568 /* Flush metadata if exist */
1569 if (ksession->metadata_stream_fd >= 0) {
1570 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
1571 if (ret < 0) {
1572 ERR("Kernel metadata flush failed");
1573 }
1574 }
1575
1576 /* Flush all buffers before stopping */
1577 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
1578 ret = kernel_flush_buffer(kchan);
1579 if (ret < 0) {
1580 ERR("Kernel flush buffer error");
1581 }
1582 }
1583
1584 ret = kernel_stop_session(ksession);
1585 if (ret < 0) {
1586 ret = LTTNG_ERR_KERN_STOP_FAIL;
1587 goto error;
1588 }
1589
1590 kernel_wait_quiescent(kernel_tracer_fd);
1591
1592 ksession->started = 0;
1593 }
1594
1595 if (usess && usess->start_trace) {
1596 usess->start_trace = 0;
1597
1598 ret = ust_app_stop_trace_all(usess);
1599 if (ret < 0) {
1600 ret = LTTNG_ERR_UST_STOP_FAIL;
1601 goto error;
1602 }
1603 }
1604
1605 ret = LTTNG_OK;
1606
1607 error:
1608 return ret;
1609 }
1610
1611 /*
1612 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
1613 */
1614 int cmd_set_consumer_uri(int domain, struct ltt_session *session,
1615 size_t nb_uri, struct lttng_uri *uris)
1616 {
1617 int ret, i;
1618 struct ltt_kernel_session *ksess = session->kernel_session;
1619 struct ltt_ust_session *usess = session->ust_session;
1620 struct consumer_output *consumer = NULL;
1621
1622 assert(session);
1623 assert(uris);
1624 assert(nb_uri > 0);
1625
1626 /* Can't enable consumer after session started. */
1627 if (session->enabled) {
1628 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1629 goto error;
1630 }
1631
1632 /*
1633 * This case switch makes sure the domain session has a temporary consumer
1634 * so the URL can be set.
1635 */
1636 switch (domain) {
1637 case 0:
1638 /* Code flow error. A session MUST always have a consumer object */
1639 assert(session->consumer);
1640 /*
1641 * The URL will be added to the tracing session consumer instead of a
1642 * specific domain consumer.
1643 */
1644 consumer = session->consumer;
1645 break;
1646 case LTTNG_DOMAIN_KERNEL:
1647 /* Code flow error if we don't have a kernel session here. */
1648 assert(ksess);
1649 assert(ksess->consumer);
1650 consumer = ksess->consumer;
1651 break;
1652 case LTTNG_DOMAIN_UST:
1653 /* Code flow error if we don't have a kernel session here. */
1654 assert(usess);
1655 assert(usess->consumer);
1656 consumer = usess->consumer;
1657 break;
1658 }
1659
1660 for (i = 0; i < nb_uri; i++) {
1661 ret = add_uri_to_consumer(consumer, &uris[i], domain, session->name);
1662 if (ret != LTTNG_OK) {
1663 goto error;
1664 }
1665 }
1666
1667 /* All good! */
1668 ret = LTTNG_OK;
1669
1670 error:
1671 return ret;
1672 }
1673
1674 /*
1675 * Command LTTNG_CREATE_SESSION processed by the client thread.
1676 */
1677 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
1678 size_t nb_uri, lttng_sock_cred *creds)
1679 {
1680 int ret;
1681 struct ltt_session *session;
1682
1683 assert(name);
1684 assert(creds);
1685
1686 /*
1687 * Verify if the session already exist
1688 *
1689 * XXX: There is no need for the session lock list here since the caller
1690 * (process_client_msg) is holding it. We might want to change that so a
1691 * single command does not lock the entire session list.
1692 */
1693 session = session_find_by_name(name);
1694 if (session != NULL) {
1695 ret = LTTNG_ERR_EXIST_SESS;
1696 goto find_error;
1697 }
1698
1699 /* Create tracing session in the registry */
1700 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
1701 LTTNG_SOCK_GET_GID_CRED(creds));
1702 if (ret != LTTNG_OK) {
1703 goto session_error;
1704 }
1705
1706 /*
1707 * Get the newly created session pointer back
1708 *
1709 * XXX: There is no need for the session lock list here since the caller
1710 * (process_client_msg) is holding it. We might want to change that so a
1711 * single command does not lock the entire session list.
1712 */
1713 session = session_find_by_name(name);
1714 assert(session);
1715
1716 /* Create default consumer output for the session not yet created. */
1717 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
1718 if (session->consumer == NULL) {
1719 ret = LTTNG_ERR_FATAL;
1720 goto consumer_error;
1721 }
1722
1723 if (uris) {
1724 ret = cmd_set_consumer_uri(0, session, nb_uri, uris);
1725 if (ret != LTTNG_OK) {
1726 goto consumer_error;
1727 }
1728 session->output_traces = 1;
1729 } else {
1730 session->output_traces = 0;
1731 DBG2("Session %s created with no output", session->name);
1732 }
1733
1734 session->consumer->enabled = 1;
1735
1736 return LTTNG_OK;
1737
1738 consumer_error:
1739 session_destroy(session);
1740 session_error:
1741 find_error:
1742 return ret;
1743 }
1744
1745 /*
1746 * Command LTTNG_DESTROY_SESSION processed by the client thread.
1747 */
1748 int cmd_destroy_session(struct ltt_session *session, int wpipe)
1749 {
1750 int ret;
1751 struct ltt_ust_session *usess;
1752 struct ltt_kernel_session *ksess;
1753
1754 /* Safety net */
1755 assert(session);
1756
1757 usess = session->ust_session;
1758 ksess = session->kernel_session;
1759
1760 /* Clean kernel session teardown */
1761 kernel_destroy_session(ksess);
1762
1763 /* UST session teardown */
1764 if (usess) {
1765 /* Close any relayd session */
1766 consumer_output_send_destroy_relayd(usess->consumer);
1767
1768 /* Destroy every UST application related to this session. */
1769 ret = ust_app_destroy_trace_all(usess);
1770 if (ret) {
1771 ERR("Error in ust_app_destroy_trace_all");
1772 }
1773
1774 /* Clean up the rest. */
1775 trace_ust_destroy_session(usess);
1776 }
1777
1778 /*
1779 * Must notify the kernel thread here to update it's poll set in order to
1780 * remove the channel(s)' fd just destroyed.
1781 */
1782 ret = notify_thread_pipe(wpipe);
1783 if (ret < 0) {
1784 PERROR("write kernel poll pipe");
1785 }
1786
1787 ret = session_destroy(session);
1788
1789 return ret;
1790 }
1791
1792 /*
1793 * Command LTTNG_CALIBRATE processed by the client thread.
1794 */
1795 int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
1796 {
1797 int ret;
1798
1799 switch (domain) {
1800 case LTTNG_DOMAIN_KERNEL:
1801 {
1802 struct lttng_kernel_calibrate kcalibrate;
1803
1804 kcalibrate.type = calibrate->type;
1805 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
1806 if (ret < 0) {
1807 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1808 goto error;
1809 }
1810 break;
1811 }
1812 case LTTNG_DOMAIN_UST:
1813 {
1814 struct lttng_ust_calibrate ucalibrate;
1815
1816 ucalibrate.type = calibrate->type;
1817 ret = ust_app_calibrate_glb(&ucalibrate);
1818 if (ret < 0) {
1819 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
1820 goto error;
1821 }
1822 break;
1823 }
1824 default:
1825 ret = LTTNG_ERR_UND;
1826 goto error;
1827 }
1828
1829 ret = LTTNG_OK;
1830
1831 error:
1832 return ret;
1833 }
1834
1835 /*
1836 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
1837 */
1838 int cmd_register_consumer(struct ltt_session *session, int domain,
1839 const char *sock_path, struct consumer_data *cdata)
1840 {
1841 int ret, sock;
1842 struct consumer_socket *socket = NULL;
1843
1844 assert(session);
1845 assert(cdata);
1846 assert(sock_path);
1847
1848 switch (domain) {
1849 case LTTNG_DOMAIN_KERNEL:
1850 {
1851 struct ltt_kernel_session *ksess = session->kernel_session;
1852
1853 assert(ksess);
1854
1855 /* Can't register a consumer if there is already one */
1856 if (ksess->consumer_fds_sent != 0) {
1857 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
1858 goto error;
1859 }
1860
1861 sock = lttcomm_connect_unix_sock(sock_path);
1862 if (sock < 0) {
1863 ret = LTTNG_ERR_CONNECT_FAIL;
1864 goto error;
1865 }
1866
1867 socket = consumer_allocate_socket(sock);
1868 if (socket == NULL) {
1869 ret = close(sock);
1870 if (ret < 0) {
1871 PERROR("close register consumer");
1872 }
1873 ret = LTTNG_ERR_FATAL;
1874 goto error;
1875 }
1876
1877 socket->lock = zmalloc(sizeof(pthread_mutex_t));
1878 if (socket->lock == NULL) {
1879 PERROR("zmalloc pthread mutex");
1880 ret = LTTNG_ERR_FATAL;
1881 goto error;
1882 }
1883 pthread_mutex_init(socket->lock, NULL);
1884 socket->registered = 1;
1885
1886 rcu_read_lock();
1887 consumer_add_socket(socket, ksess->consumer);
1888 rcu_read_unlock();
1889
1890 pthread_mutex_lock(&cdata->pid_mutex);
1891 cdata->pid = -1;
1892 pthread_mutex_unlock(&cdata->pid_mutex);
1893
1894 break;
1895 }
1896 default:
1897 /* TODO: Userspace tracing */
1898 ret = LTTNG_ERR_UND;
1899 goto error;
1900 }
1901
1902 return LTTNG_OK;
1903
1904 error:
1905 if (socket) {
1906 consumer_destroy_socket(socket);
1907 }
1908 return ret;
1909 }
1910
1911 /*
1912 * Command LTTNG_LIST_DOMAINS processed by the client thread.
1913 */
1914 ssize_t cmd_list_domains(struct ltt_session *session,
1915 struct lttng_domain **domains)
1916 {
1917 int ret, index = 0;
1918 ssize_t nb_dom = 0;
1919
1920 if (session->kernel_session != NULL) {
1921 DBG3("Listing domains found kernel domain");
1922 nb_dom++;
1923 }
1924
1925 if (session->ust_session != NULL) {
1926 DBG3("Listing domains found UST global domain");
1927 nb_dom++;
1928 }
1929
1930 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
1931 if (*domains == NULL) {
1932 ret = LTTNG_ERR_FATAL;
1933 goto error;
1934 }
1935
1936 if (session->kernel_session != NULL) {
1937 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
1938 index++;
1939 }
1940
1941 if (session->ust_session != NULL) {
1942 (*domains)[index].type = LTTNG_DOMAIN_UST;
1943 (*domains)[index].buf_type = session->ust_session->buffer_type;
1944 index++;
1945 }
1946
1947 return nb_dom;
1948
1949 error:
1950 /* Return negative value to differentiate return code */
1951 return -ret;
1952 }
1953
1954
1955 /*
1956 * Command LTTNG_LIST_CHANNELS processed by the client thread.
1957 */
1958 ssize_t cmd_list_channels(int domain, struct ltt_session *session,
1959 struct lttng_channel **channels)
1960 {
1961 int ret;
1962 ssize_t nb_chan = 0;
1963
1964 switch (domain) {
1965 case LTTNG_DOMAIN_KERNEL:
1966 if (session->kernel_session != NULL) {
1967 nb_chan = session->kernel_session->channel_count;
1968 }
1969 DBG3("Number of kernel channels %zd", nb_chan);
1970 if (nb_chan <= 0) {
1971 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1972 }
1973 break;
1974 case LTTNG_DOMAIN_UST:
1975 if (session->ust_session != NULL) {
1976 nb_chan = lttng_ht_get_count(
1977 session->ust_session->domain_global.channels);
1978 }
1979 DBG3("Number of UST global channels %zd", nb_chan);
1980 if (nb_chan <= 0) {
1981 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1982 }
1983 break;
1984 default:
1985 *channels = NULL;
1986 ret = LTTNG_ERR_UND;
1987 goto error;
1988 }
1989
1990 if (nb_chan > 0) {
1991 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
1992 if (*channels == NULL) {
1993 ret = LTTNG_ERR_FATAL;
1994 goto error;
1995 }
1996
1997 list_lttng_channels(domain, session, *channels);
1998 } else {
1999 *channels = NULL;
2000 /* Ret value was set in the domain switch case */
2001 goto error;
2002 }
2003
2004 return nb_chan;
2005
2006 error:
2007 /* Return negative value to differentiate return code */
2008 return -ret;
2009 }
2010
2011 /*
2012 * Command LTTNG_LIST_EVENTS processed by the client thread.
2013 */
2014 ssize_t cmd_list_events(int domain, struct ltt_session *session,
2015 char *channel_name, struct lttng_event **events)
2016 {
2017 int ret = 0;
2018 ssize_t nb_event = 0;
2019
2020 switch (domain) {
2021 case LTTNG_DOMAIN_KERNEL:
2022 if (session->kernel_session != NULL) {
2023 nb_event = list_lttng_kernel_events(channel_name,
2024 session->kernel_session, events);
2025 }
2026 break;
2027 case LTTNG_DOMAIN_UST:
2028 {
2029 if (session->ust_session != NULL) {
2030 nb_event = list_lttng_ust_global_events(channel_name,
2031 &session->ust_session->domain_global, events);
2032 }
2033 break;
2034 }
2035 default:
2036 ret = LTTNG_ERR_UND;
2037 goto error;
2038 }
2039
2040 return nb_event;
2041
2042 error:
2043 /* Return negative value to differentiate return code */
2044 return -ret;
2045 }
2046
2047 /*
2048 * Using the session list, filled a lttng_session array to send back to the
2049 * client for session listing.
2050 *
2051 * The session list lock MUST be acquired before calling this function. Use
2052 * session_lock_list() and session_unlock_list().
2053 */
2054 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2055 gid_t gid)
2056 {
2057 int ret;
2058 unsigned int i = 0;
2059 struct ltt_session *session;
2060 struct ltt_session_list *list = session_get_list();
2061
2062 DBG("Getting all available session for UID %d GID %d",
2063 uid, gid);
2064 /*
2065 * Iterate over session list and append data after the control struct in
2066 * the buffer.
2067 */
2068 cds_list_for_each_entry(session, &list->head, list) {
2069 /*
2070 * Only list the sessions the user can control.
2071 */
2072 if (!session_access_ok(session, uid, gid)) {
2073 continue;
2074 }
2075
2076 struct ltt_kernel_session *ksess = session->kernel_session;
2077 struct ltt_ust_session *usess = session->ust_session;
2078
2079 if (session->consumer->type == CONSUMER_DST_NET ||
2080 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2081 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2082 ret = build_network_session_path(sessions[i].path,
2083 sizeof(sessions[i].path), session);
2084 } else {
2085 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
2086 session->consumer->dst.trace_path);
2087 }
2088 if (ret < 0) {
2089 PERROR("snprintf session path");
2090 continue;
2091 }
2092
2093 strncpy(sessions[i].name, session->name, NAME_MAX);
2094 sessions[i].name[NAME_MAX - 1] = '\0';
2095 sessions[i].enabled = session->enabled;
2096 i++;
2097 }
2098 }
2099
2100 /*
2101 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2102 * ready for trace analysis (or anykind of reader) or else 1 for pending data.
2103 */
2104 int cmd_data_pending(struct ltt_session *session)
2105 {
2106 int ret;
2107 struct ltt_kernel_session *ksess = session->kernel_session;
2108 struct ltt_ust_session *usess = session->ust_session;
2109
2110 assert(session);
2111
2112 /* Session MUST be stopped to ask for data availability. */
2113 if (session->enabled) {
2114 ret = LTTNG_ERR_SESSION_STARTED;
2115 goto error;
2116 }
2117
2118 if (ksess && ksess->consumer) {
2119 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2120 if (ret == 1) {
2121 /* Data is still being extracted for the kernel. */
2122 goto error;
2123 }
2124 }
2125
2126 if (usess && usess->consumer) {
2127 ret = consumer_is_data_pending(usess->id, usess->consumer);
2128 if (ret == 1) {
2129 /* Data is still being extracted for the kernel. */
2130 goto error;
2131 }
2132 }
2133
2134 /* Data is ready to be read by a viewer */
2135 ret = 0;
2136
2137 error:
2138 return ret;
2139 }
2140
2141 /*
2142 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
2143 *
2144 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2145 */
2146 int cmd_snapshot_add_output(struct ltt_session *session,
2147 struct lttng_snapshot_output *output, uint32_t *id)
2148 {
2149 int ret;
2150 struct snapshot_output *new_output;
2151
2152 assert(session);
2153 assert(output);
2154
2155 DBG("Cmd snapshot add output for session %s", session->name);
2156
2157 /*
2158 * Persmission denied to create an output if the session is not set in no
2159 * output mode.
2160 */
2161 if (session->output_traces) {
2162 ret = LTTNG_ERR_EPERM;
2163 goto error;
2164 }
2165
2166 /* Only one output is allowed until we have the "tee" feature. */
2167 if (session->snapshot.nb_output == 1) {
2168 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
2169 goto error;
2170 }
2171
2172 new_output = snapshot_output_alloc();
2173 if (!new_output) {
2174 ret = LTTNG_ERR_NOMEM;
2175 goto error;
2176 }
2177
2178 ret = snapshot_output_init(output->max_size, output->name,
2179 output->ctrl_url, output->data_url, session->consumer, new_output,
2180 &session->snapshot);
2181 if (ret < 0) {
2182 if (ret == -ENOMEM) {
2183 ret = LTTNG_ERR_NOMEM;
2184 } else {
2185 ret = LTTNG_ERR_INVALID;
2186 }
2187 goto free_error;
2188 }
2189
2190 /*
2191 * Copy sockets so the snapshot output can use them on destroy.
2192 */
2193
2194 if (session->ust_session) {
2195 ret = consumer_copy_sockets(new_output->consumer,
2196 session->ust_session->consumer);
2197 if (ret < 0) {
2198 goto free_error;
2199 }
2200 new_output->ust_sockets_copied = 1;
2201 }
2202 if (session->kernel_session) {
2203 ret = consumer_copy_sockets(new_output->consumer,
2204 session->kernel_session->consumer);
2205 if (ret < 0) {
2206 goto free_error;
2207 }
2208 new_output->kernel_sockets_copied = 1;
2209 }
2210
2211 rcu_read_lock();
2212 snapshot_add_output(&session->snapshot, new_output);
2213 if (id) {
2214 *id = new_output->id;
2215 }
2216 rcu_read_unlock();
2217
2218 return LTTNG_OK;
2219
2220 free_error:
2221 snapshot_output_destroy(new_output);
2222 error:
2223 return ret;
2224 }
2225
2226 /*
2227 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
2228 *
2229 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2230 */
2231 int cmd_snapshot_del_output(struct ltt_session *session,
2232 struct lttng_snapshot_output *output)
2233 {
2234 int ret;
2235 struct snapshot_output *sout;
2236
2237 assert(session);
2238 assert(output);
2239
2240 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
2241 session->name);
2242
2243 rcu_read_lock();
2244
2245 /*
2246 * Persmission denied to create an output if the session is not set in no
2247 * output mode.
2248 */
2249 if (session->output_traces) {
2250 ret = LTTNG_ERR_EPERM;
2251 goto error;
2252 }
2253
2254 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
2255 if (!sout) {
2256 ret = LTTNG_ERR_INVALID;
2257 goto error;
2258 }
2259
2260 snapshot_delete_output(&session->snapshot, sout);
2261 snapshot_output_destroy(sout);
2262 ret = LTTNG_OK;
2263
2264 error:
2265 rcu_read_unlock();
2266 return ret;
2267 }
2268
2269 /*
2270 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
2271 *
2272 * If no output is available, outputs is untouched and 0 is returned.
2273 *
2274 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
2275 */
2276 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
2277 struct lttng_snapshot_output **outputs)
2278 {
2279 int ret, idx = 0;
2280 struct lttng_snapshot_output *list;
2281 struct lttng_ht_iter iter;
2282 struct snapshot_output *output;
2283
2284 assert(session);
2285 assert(outputs);
2286
2287 DBG("Cmd snapshot list outputs for session %s", session->name);
2288
2289 /*
2290 * Persmission denied to create an output if the session is not set in no
2291 * output mode.
2292 */
2293 if (session->output_traces) {
2294 ret = LTTNG_ERR_EPERM;
2295 goto error;
2296 }
2297
2298 if (session->snapshot.nb_output == 0) {
2299 ret = 0;
2300 goto error;
2301 }
2302
2303 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
2304 if (!list) {
2305 ret = LTTNG_ERR_NOMEM;
2306 goto error;
2307 }
2308
2309 /* Copy list from session to the new list object. */
2310 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
2311 output, node.node) {
2312 assert(output->consumer);
2313 list[idx].id = output->id;
2314 list[idx].max_size = output->max_size;
2315 strncpy(list[idx].name, output->name, sizeof(list[idx].name));
2316 if (output->consumer->type == CONSUMER_DST_LOCAL) {
2317 strncpy(list[idx].ctrl_url, output->consumer->dst.trace_path,
2318 sizeof(list[idx].ctrl_url));
2319 } else {
2320 /* Control URI. */
2321 ret = uri_to_str_url(&output->consumer->dst.net.control,
2322 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
2323 if (ret < 0) {
2324 ret = LTTNG_ERR_NOMEM;
2325 goto free_error;
2326 }
2327
2328 /* Data URI. */
2329 ret = uri_to_str_url(&output->consumer->dst.net.data,
2330 list[idx].data_url, sizeof(list[idx].data_url));
2331 if (ret < 0) {
2332 ret = LTTNG_ERR_NOMEM;
2333 goto free_error;
2334 }
2335 }
2336 idx++;
2337 }
2338
2339 *outputs = list;
2340 return session->snapshot.nb_output;
2341
2342 free_error:
2343 free(list);
2344 error:
2345 return -ret;
2346 }
2347
2348 /*
2349 * Send relayd sockets from snapshot output to consumer. Ignore request if the
2350 * snapshot output is *not* set with a remote destination.
2351 *
2352 * Return 0 on success or else a negative value.
2353 */
2354 static int set_relayd_for_snapshot(struct consumer_output *consumer,
2355 struct snapshot_output *snap_output, struct ltt_session *session)
2356 {
2357 int ret = 0;
2358 struct lttng_ht_iter iter;
2359 struct consumer_socket *socket;
2360
2361 assert(consumer);
2362 assert(snap_output);
2363 assert(session);
2364
2365 DBG2("Set relayd object from snapshot output");
2366
2367 /* Ignore if snapshot consumer output is not network. */
2368 if (snap_output->consumer->type != CONSUMER_DST_NET) {
2369 goto error;
2370 }
2371
2372 /*
2373 * For each consumer socket, create and send the relayd object of the
2374 * snapshot output.
2375 */
2376 rcu_read_lock();
2377 cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
2378 node.node) {
2379 ret = send_consumer_relayd_sockets(0, session->id,
2380 snap_output->consumer, socket);
2381 if (ret < 0) {
2382 rcu_read_unlock();
2383 goto error;
2384 }
2385 }
2386 rcu_read_unlock();
2387
2388 error:
2389 return ret;
2390 }
2391
2392 /*
2393 * Record a kernel snapshot.
2394 *
2395 * Return 0 on success or else a negative value.
2396 */
2397 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
2398 struct snapshot_output *output, struct ltt_session *session, int wait)
2399 {
2400 int ret;
2401
2402 assert(ksess);
2403 assert(output);
2404 assert(session);
2405
2406 if (!output->kernel_sockets_copied) {
2407 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
2408 if (ret < 0) {
2409 goto error;
2410 }
2411 output->kernel_sockets_copied = 1;
2412 }
2413
2414 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
2415 if (ret < 0) {
2416 goto error;
2417 }
2418
2419 ret = kernel_snapshot_record(ksess, output, wait);
2420 if (ret < 0) {
2421 goto error;
2422 }
2423
2424 error:
2425 return ret;
2426 }
2427
2428 /*
2429 * Record a UST snapshot.
2430 *
2431 * Return 0 on success or else a negative value.
2432 */
2433 static int record_ust_snapshot(struct ltt_ust_session *usess,
2434 struct snapshot_output *output, struct ltt_session *session, int wait)
2435 {
2436 int ret;
2437
2438 assert(usess);
2439 assert(output);
2440 assert(session);
2441
2442 if (!output->ust_sockets_copied) {
2443 ret = consumer_copy_sockets(output->consumer, usess->consumer);
2444 if (ret < 0) {
2445 goto error;
2446 }
2447 output->ust_sockets_copied = 1;
2448 }
2449
2450 ret = set_relayd_for_snapshot(usess->consumer, output, session);
2451 if (ret < 0) {
2452 goto error;
2453 }
2454
2455 ret = ust_app_snapshot_record(usess, output, wait);
2456 if (ret < 0) {
2457 goto error;
2458 }
2459
2460 error:
2461 return ret;
2462 }
2463
2464 /*
2465 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
2466 *
2467 * The wait parameter is ignored so this call always wait for the snapshot to
2468 * complete before returning.
2469 *
2470 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2471 */
2472 int cmd_snapshot_record(struct ltt_session *session,
2473 struct lttng_snapshot_output *output, int wait)
2474 {
2475 int ret = LTTNG_OK;
2476 struct snapshot_output *tmp_sout = NULL;
2477
2478 assert(session);
2479
2480 DBG("Cmd snapshot record for session %s", session->name);
2481
2482 /*
2483 * Persmission denied to create an output if the session is not set in no
2484 * output mode.
2485 */
2486 if (session->output_traces) {
2487 ret = LTTNG_ERR_EPERM;
2488 goto error;
2489 }
2490
2491 /* The session needs to be started at least once. */
2492 if (!session->started) {
2493 ret = LTTNG_ERR_START_SESSION_ONCE;
2494 goto error;
2495 }
2496
2497 /* Use temporary output for the session. */
2498 if (output && *output->ctrl_url != '\0') {
2499 tmp_sout = snapshot_output_alloc();
2500 if (!tmp_sout) {
2501 ret = LTTNG_ERR_NOMEM;
2502 goto error;
2503 }
2504
2505 ret = snapshot_output_init(output->max_size, output->name,
2506 output->ctrl_url, output->data_url, session->consumer,
2507 tmp_sout, NULL);
2508 if (ret < 0) {
2509 if (ret == -ENOMEM) {
2510 ret = LTTNG_ERR_NOMEM;
2511 } else {
2512 ret = LTTNG_ERR_INVALID;
2513 }
2514 goto error;
2515 }
2516 }
2517
2518 if (session->kernel_session) {
2519 struct ltt_kernel_session *ksess = session->kernel_session;
2520
2521 if (tmp_sout) {
2522 ret = record_kernel_snapshot(ksess, tmp_sout, session, wait);
2523 if (ret < 0) {
2524 goto error;
2525 }
2526 } else {
2527 struct snapshot_output *sout;
2528 struct lttng_ht_iter iter;
2529
2530 rcu_read_lock();
2531 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
2532 &iter.iter, sout, node.node) {
2533 ret = record_kernel_snapshot(ksess, sout, session, wait);
2534 if (ret < 0) {
2535 rcu_read_unlock();
2536 goto error;
2537 }
2538 }
2539 rcu_read_unlock();
2540 }
2541 }
2542
2543 if (session->ust_session) {
2544 struct ltt_ust_session *usess = session->ust_session;
2545
2546 if (tmp_sout) {
2547 ret = record_ust_snapshot(usess, tmp_sout, session, wait);
2548 if (ret < 0) {
2549 goto error;
2550 }
2551 } else {
2552 struct snapshot_output *sout;
2553 struct lttng_ht_iter iter;
2554
2555 rcu_read_lock();
2556 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
2557 &iter.iter, sout, node.node) {
2558 ret = record_ust_snapshot(usess, tmp_sout, session, wait);
2559 if (ret < 0) {
2560 rcu_read_unlock();
2561 goto error;
2562 }
2563 }
2564 rcu_read_unlock();
2565 }
2566 }
2567
2568 error:
2569 if (tmp_sout) {
2570 snapshot_output_destroy(tmp_sout);
2571 }
2572 return ret;
2573 }
2574
2575 /*
2576 * Init command subsystem.
2577 */
2578 void cmd_init(void)
2579 {
2580 /*
2581 * Set network sequence index to 1 for streams to match a relayd
2582 * socket on the consumer side.
2583 */
2584 pthread_mutex_lock(&relayd_net_seq_idx_lock);
2585 relayd_net_seq_idx = 1;
2586 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
2587
2588 DBG("Command subsystem initialized");
2589 }
LTTng 2.0 tools and control repository
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