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Fix: channels can be _enabled_ after tracing is started, but not created
[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 #include <common/utils.h>
29
30 #include "channel.h"
31 #include "consumer.h"
32 #include "event.h"
33 #include "health.h"
34 #include "kernel.h"
35 #include "kernel-consumer.h"
36 #include "lttng-sessiond.h"
37 #include "utils.h"
38
39 #include "cmd.h"
40
41 /*
42 * Used to keep a unique index for each relayd socket created where this value
43 * is associated with streams on the consumer so it can match the right relayd
44 * to send to. It must be accessed with the relayd_net_seq_idx_lock
45 * held.
46 */
47 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
48 static uint64_t relayd_net_seq_idx;
49
50 /*
51 * Create a session path used by list_lttng_sessions for the case that the
52 * session consumer is on the network.
53 */
54 static int build_network_session_path(char *dst, size_t size,
55 struct ltt_session *session)
56 {
57 int ret, kdata_port, udata_port;
58 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
59 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
60
61 assert(session);
62 assert(dst);
63
64 memset(tmp_urls, 0, sizeof(tmp_urls));
65 memset(tmp_uurl, 0, sizeof(tmp_uurl));
66
67 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
68
69 if (session->kernel_session && session->kernel_session->consumer) {
70 kuri = &session->kernel_session->consumer->dst.net.control;
71 kdata_port = session->kernel_session->consumer->dst.net.data.port;
72 }
73
74 if (session->ust_session && session->ust_session->consumer) {
75 uuri = &session->ust_session->consumer->dst.net.control;
76 udata_port = session->ust_session->consumer->dst.net.data.port;
77 }
78
79 if (uuri == NULL && kuri == NULL) {
80 uri = &session->consumer->dst.net.control;
81 kdata_port = session->consumer->dst.net.data.port;
82 } else if (kuri && uuri) {
83 ret = uri_compare(kuri, uuri);
84 if (ret) {
85 /* Not Equal */
86 uri = kuri;
87 /* Build uuri URL string */
88 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
89 if (ret < 0) {
90 goto error;
91 }
92 } else {
93 uri = kuri;
94 }
95 } else if (kuri && uuri == NULL) {
96 uri = kuri;
97 } else if (uuri && kuri == NULL) {
98 uri = uuri;
99 }
100
101 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
102 if (ret < 0) {
103 goto error;
104 }
105
106 /*
107 * Do we have a UST url set. If yes, this means we have both kernel and UST
108 * to print.
109 */
110 if (*tmp_uurl != '\0') {
111 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
112 tmp_urls, kdata_port, tmp_uurl, udata_port);
113 } else {
114 int dport;
115 if (kuri || (!kuri && !uuri)) {
116 dport = kdata_port;
117 } else {
118 /* No kernel URI, use the UST port. */
119 dport = udata_port;
120 }
121 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
122 }
123
124 error:
125 return ret;
126 }
127
128 /*
129 * Fill lttng_channel array of all channels.
130 */
131 static void list_lttng_channels(int domain, struct ltt_session *session,
132 struct lttng_channel *channels)
133 {
134 int i = 0;
135 struct ltt_kernel_channel *kchan;
136
137 DBG("Listing channels for session %s", session->name);
138
139 switch (domain) {
140 case LTTNG_DOMAIN_KERNEL:
141 /* Kernel channels */
142 if (session->kernel_session != NULL) {
143 cds_list_for_each_entry(kchan,
144 &session->kernel_session->channel_list.head, list) {
145 /* Copy lttng_channel struct to array */
146 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
147 channels[i].enabled = kchan->enabled;
148 i++;
149 }
150 }
151 break;
152 case LTTNG_DOMAIN_UST:
153 {
154 struct lttng_ht_iter iter;
155 struct ltt_ust_channel *uchan;
156
157 rcu_read_lock();
158 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
159 &iter.iter, uchan, node.node) {
160 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
161 channels[i].attr.overwrite = uchan->attr.overwrite;
162 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
163 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
164 channels[i].attr.switch_timer_interval =
165 uchan->attr.switch_timer_interval;
166 channels[i].attr.read_timer_interval =
167 uchan->attr.read_timer_interval;
168 channels[i].enabled = uchan->enabled;
169 switch (uchan->attr.output) {
170 case LTTNG_UST_MMAP:
171 default:
172 channels[i].attr.output = LTTNG_EVENT_MMAP;
173 break;
174 }
175 i++;
176 }
177 rcu_read_unlock();
178 break;
179 }
180 default:
181 break;
182 }
183 }
184
185 /*
186 * Create a list of ust global domain events.
187 */
188 static int list_lttng_ust_global_events(char *channel_name,
189 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
190 {
191 int i = 0, ret = 0;
192 unsigned int nb_event = 0;
193 struct lttng_ht_iter iter;
194 struct lttng_ht_node_str *node;
195 struct ltt_ust_channel *uchan;
196 struct ltt_ust_event *uevent;
197 struct lttng_event *tmp;
198
199 DBG("Listing UST global events for channel %s", channel_name);
200
201 rcu_read_lock();
202
203 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
204 node = lttng_ht_iter_get_node_str(&iter);
205 if (node == NULL) {
206 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
207 goto error;
208 }
209
210 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
211
212 nb_event += lttng_ht_get_count(uchan->events);
213
214 if (nb_event == 0) {
215 ret = nb_event;
216 goto error;
217 }
218
219 DBG3("Listing UST global %d events", nb_event);
220
221 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
222 if (tmp == NULL) {
223 ret = LTTNG_ERR_FATAL;
224 goto error;
225 }
226
227 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
228 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
229 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
230 tmp[i].enabled = uevent->enabled;
231
232 switch (uevent->attr.instrumentation) {
233 case LTTNG_UST_TRACEPOINT:
234 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
235 break;
236 case LTTNG_UST_PROBE:
237 tmp[i].type = LTTNG_EVENT_PROBE;
238 break;
239 case LTTNG_UST_FUNCTION:
240 tmp[i].type = LTTNG_EVENT_FUNCTION;
241 break;
242 }
243
244 tmp[i].loglevel = uevent->attr.loglevel;
245 switch (uevent->attr.loglevel_type) {
246 case LTTNG_UST_LOGLEVEL_ALL:
247 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
248 break;
249 case LTTNG_UST_LOGLEVEL_RANGE:
250 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
251 break;
252 case LTTNG_UST_LOGLEVEL_SINGLE:
253 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
254 break;
255 }
256 if (uevent->filter) {
257 tmp[i].filter = 1;
258 }
259 i++;
260 }
261
262 ret = nb_event;
263 *events = tmp;
264
265 error:
266 rcu_read_unlock();
267 return ret;
268 }
269
270 /*
271 * Fill lttng_event array of all kernel events in the channel.
272 */
273 static int list_lttng_kernel_events(char *channel_name,
274 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
275 {
276 int i = 0, ret;
277 unsigned int nb_event;
278 struct ltt_kernel_event *event;
279 struct ltt_kernel_channel *kchan;
280
281 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
282 if (kchan == NULL) {
283 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
284 goto error;
285 }
286
287 nb_event = kchan->event_count;
288
289 DBG("Listing events for channel %s", kchan->channel->name);
290
291 if (nb_event == 0) {
292 goto end;
293 }
294
295 *events = zmalloc(nb_event * sizeof(struct lttng_event));
296 if (*events == NULL) {
297 ret = LTTNG_ERR_FATAL;
298 goto error;
299 }
300
301 /* Kernel channels */
302 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
303 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
304 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
305 (*events)[i].enabled = event->enabled;
306
307 switch (event->event->instrumentation) {
308 case LTTNG_KERNEL_TRACEPOINT:
309 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
310 break;
311 case LTTNG_KERNEL_KRETPROBE:
312 (*events)[i].type = LTTNG_EVENT_FUNCTION;
313 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
314 sizeof(struct lttng_kernel_kprobe));
315 break;
316 case LTTNG_KERNEL_KPROBE:
317 (*events)[i].type = LTTNG_EVENT_PROBE;
318 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
319 sizeof(struct lttng_kernel_kprobe));
320 break;
321 case LTTNG_KERNEL_FUNCTION:
322 (*events)[i].type = LTTNG_EVENT_FUNCTION;
323 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
324 sizeof(struct lttng_kernel_function));
325 break;
326 case LTTNG_KERNEL_NOOP:
327 (*events)[i].type = LTTNG_EVENT_NOOP;
328 break;
329 case LTTNG_KERNEL_SYSCALL:
330 (*events)[i].type = LTTNG_EVENT_SYSCALL;
331 break;
332 case LTTNG_KERNEL_ALL:
333 assert(0);
334 break;
335 }
336 i++;
337 }
338
339 end:
340 return nb_event;
341
342 error:
343 /* Negate the error code to differentiate the size from an error */
344 return -ret;
345 }
346
347 /*
348 * Add URI so the consumer output object. Set the correct path depending on the
349 * domain adding the default trace directory.
350 */
351 static int add_uri_to_consumer(struct consumer_output *consumer,
352 struct lttng_uri *uri, int domain, const char *session_name)
353 {
354 int ret = LTTNG_OK;
355 const char *default_trace_dir;
356
357 assert(uri);
358
359 if (consumer == NULL) {
360 DBG("No consumer detected. Don't add URI. Stopping.");
361 ret = LTTNG_ERR_NO_CONSUMER;
362 goto error;
363 }
364
365 switch (domain) {
366 case LTTNG_DOMAIN_KERNEL:
367 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
368 break;
369 case LTTNG_DOMAIN_UST:
370 default_trace_dir = DEFAULT_UST_TRACE_DIR;
371 break;
372 default:
373 /*
374 * This case is possible is we try to add the URI to the global tracing
375 * session consumer object which in this case there is no subdir.
376 */
377 default_trace_dir = "";
378 }
379
380 switch (uri->dtype) {
381 case LTTNG_DST_IPV4:
382 case LTTNG_DST_IPV6:
383 DBG2("Setting network URI to consumer");
384
385 if (consumer->type == CONSUMER_DST_NET) {
386 if ((uri->stype == LTTNG_STREAM_CONTROL &&
387 consumer->dst.net.control_isset) ||
388 (uri->stype == LTTNG_STREAM_DATA &&
389 consumer->dst.net.data_isset)) {
390 ret = LTTNG_ERR_URL_EXIST;
391 goto error;
392 }
393 } else {
394 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
395 }
396
397 consumer->type = CONSUMER_DST_NET;
398
399 /* Set URI into consumer output object */
400 ret = consumer_set_network_uri(consumer, uri);
401 if (ret < 0) {
402 ret = -ret;
403 goto error;
404 } else if (ret == 1) {
405 /*
406 * URI was the same in the consumer so we do not append the subdir
407 * again so to not duplicate output dir.
408 */
409 goto error;
410 }
411
412 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
413 ret = consumer_set_subdir(consumer, session_name);
414 if (ret < 0) {
415 ret = LTTNG_ERR_FATAL;
416 goto error;
417 }
418 }
419
420 if (uri->stype == LTTNG_STREAM_CONTROL) {
421 /* On a new subdir, reappend the default trace dir. */
422 strncat(consumer->subdir, default_trace_dir,
423 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
424 DBG3("Append domain trace name to subdir %s", consumer->subdir);
425 }
426
427 break;
428 case LTTNG_DST_PATH:
429 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
430 memset(consumer->dst.trace_path, 0,
431 sizeof(consumer->dst.trace_path));
432 strncpy(consumer->dst.trace_path, uri->dst.path,
433 sizeof(consumer->dst.trace_path));
434 /* Append default trace dir */
435 strncat(consumer->dst.trace_path, default_trace_dir,
436 sizeof(consumer->dst.trace_path) -
437 strlen(consumer->dst.trace_path) - 1);
438 /* Flag consumer as local. */
439 consumer->type = CONSUMER_DST_LOCAL;
440 break;
441 }
442
443 ret = LTTNG_OK;
444
445 error:
446 return ret;
447 }
448
449 /*
450 * Init tracing by creating trace directory and sending fds kernel consumer.
451 */
452 static int init_kernel_tracing(struct ltt_kernel_session *session)
453 {
454 int ret = 0;
455 struct lttng_ht_iter iter;
456 struct consumer_socket *socket;
457
458 assert(session);
459
460 rcu_read_lock();
461
462 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
463 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
464 socket, node.node) {
465 /* Code flow error */
466 assert(socket->fd >= 0);
467
468 pthread_mutex_lock(socket->lock);
469 ret = kernel_consumer_send_session(socket, session);
470 pthread_mutex_unlock(socket->lock);
471 if (ret < 0) {
472 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
473 goto error;
474 }
475 }
476 }
477
478 error:
479 rcu_read_unlock();
480 return ret;
481 }
482
483 /*
484 * Create a socket to the relayd using the URI.
485 *
486 * On success, the relayd_sock pointer is set to the created socket.
487 * Else, it's stays untouched and a lttcomm error code is returned.
488 */
489 static int create_connect_relayd(struct lttng_uri *uri,
490 struct lttcomm_relayd_sock **relayd_sock)
491 {
492 int ret;
493 struct lttcomm_relayd_sock *rsock;
494
495 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
496 RELAYD_VERSION_COMM_MINOR);
497 if (!rsock) {
498 ret = LTTNG_ERR_FATAL;
499 goto error;
500 }
501
502 /*
503 * Connect to relayd so we can proceed with a session creation. This call
504 * can possibly block for an arbitrary amount of time to set the health
505 * state to be in poll execution.
506 */
507 health_poll_entry();
508 ret = relayd_connect(rsock);
509 health_poll_exit();
510 if (ret < 0) {
511 ERR("Unable to reach lttng-relayd");
512 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
513 goto free_sock;
514 }
515
516 /* Create socket for control stream. */
517 if (uri->stype == LTTNG_STREAM_CONTROL) {
518 DBG3("Creating relayd stream socket from URI");
519
520 /* Check relayd version */
521 ret = relayd_version_check(rsock);
522 if (ret < 0) {
523 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
524 goto close_sock;
525 }
526 } else if (uri->stype == LTTNG_STREAM_DATA) {
527 DBG3("Creating relayd data socket from URI");
528 } else {
529 /* Command is not valid */
530 ERR("Relayd invalid stream type: %d", uri->stype);
531 ret = LTTNG_ERR_INVALID;
532 goto close_sock;
533 }
534
535 *relayd_sock = rsock;
536
537 return LTTNG_OK;
538
539 close_sock:
540 /* The returned value is not useful since we are on an error path. */
541 (void) relayd_close(rsock);
542 free_sock:
543 free(rsock);
544 error:
545 return ret;
546 }
547
548 /*
549 * Connect to the relayd using URI and send the socket to the right consumer.
550 */
551 static int send_consumer_relayd_socket(int domain, unsigned int session_id,
552 struct lttng_uri *relayd_uri, struct consumer_output *consumer,
553 struct consumer_socket *consumer_sock)
554 {
555 int ret;
556 struct lttcomm_relayd_sock *rsock = NULL;
557
558 /* Connect to relayd and make version check if uri is the control. */
559 ret = create_connect_relayd(relayd_uri, &rsock);
560 if (ret != LTTNG_OK) {
561 goto error;
562 }
563 assert(rsock);
564
565 /* Set the network sequence index if not set. */
566 if (consumer->net_seq_index == (uint64_t) -1ULL) {
567 pthread_mutex_lock(&relayd_net_seq_idx_lock);
568 /*
569 * Increment net_seq_idx because we are about to transfer the
570 * new relayd socket to the consumer.
571 * Assign unique key so the consumer can match streams.
572 */
573 consumer->net_seq_index = ++relayd_net_seq_idx;
574 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
575 }
576
577 /* Send relayd socket to consumer. */
578 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
579 relayd_uri->stype, session_id);
580 if (ret < 0) {
581 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
582 goto close_sock;
583 }
584
585 /* Flag that the corresponding socket was sent. */
586 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
587 consumer_sock->control_sock_sent = 1;
588 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
589 consumer_sock->data_sock_sent = 1;
590 }
591
592 ret = LTTNG_OK;
593
594 /*
595 * Close socket which was dup on the consumer side. The session daemon does
596 * NOT keep track of the relayd socket(s) once transfer to the consumer.
597 */
598
599 close_sock:
600 (void) relayd_close(rsock);
601 free(rsock);
602
603 error:
604 if (ret != LTTNG_OK) {
605 /*
606 * The consumer output for this session should not be used anymore
607 * since the relayd connection failed thus making any tracing or/and
608 * streaming not usable.
609 */
610 consumer->enabled = 0;
611 }
612 return ret;
613 }
614
615 /*
616 * Send both relayd sockets to a specific consumer and domain. This is a
617 * helper function to facilitate sending the information to the consumer for a
618 * session.
619 */
620 static int send_consumer_relayd_sockets(int domain, unsigned int session_id,
621 struct consumer_output *consumer, struct consumer_socket *sock)
622 {
623 int ret = LTTNG_OK;
624
625 assert(consumer);
626 assert(sock);
627
628 /* Sending control relayd socket. */
629 if (!sock->control_sock_sent) {
630 ret = send_consumer_relayd_socket(domain, session_id,
631 &consumer->dst.net.control, consumer, sock);
632 if (ret != LTTNG_OK) {
633 goto error;
634 }
635 }
636
637 /* Sending data relayd socket. */
638 if (!sock->data_sock_sent) {
639 ret = send_consumer_relayd_socket(domain, session_id,
640 &consumer->dst.net.data, consumer, sock);
641 if (ret != LTTNG_OK) {
642 goto error;
643 }
644 }
645
646 error:
647 return ret;
648 }
649
650 /*
651 * Setup relayd connections for a tracing session. First creates the socket to
652 * the relayd and send them to the right domain consumer. Consumer type MUST be
653 * network.
654 */
655 int cmd_setup_relayd(struct ltt_session *session)
656 {
657 int ret = LTTNG_OK;
658 struct ltt_ust_session *usess;
659 struct ltt_kernel_session *ksess;
660 struct consumer_socket *socket;
661 struct lttng_ht_iter iter;
662
663 assert(session);
664
665 usess = session->ust_session;
666 ksess = session->kernel_session;
667
668 DBG("Setting relayd for session %s", session->name);
669
670 rcu_read_lock();
671
672 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
673 && usess->consumer->enabled) {
674 /* For each consumer socket, send relayd sockets */
675 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
676 socket, node.node) {
677 /* Code flow error */
678 assert(socket->fd >= 0);
679
680 pthread_mutex_lock(socket->lock);
681 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
682 usess->consumer, socket);
683 pthread_mutex_unlock(socket->lock);
684 if (ret != LTTNG_OK) {
685 goto error;
686 }
687 /* Session is now ready for network streaming. */
688 session->net_handle = 1;
689 }
690 }
691
692 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
693 && ksess->consumer->enabled) {
694 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
695 socket, node.node) {
696 /* Code flow error */
697 assert(socket->fd >= 0);
698
699 pthread_mutex_lock(socket->lock);
700 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
701 ksess->consumer, socket);
702 pthread_mutex_unlock(socket->lock);
703 if (ret != LTTNG_OK) {
704 goto error;
705 }
706 /* Session is now ready for network streaming. */
707 session->net_handle = 1;
708 }
709 }
710
711 error:
712 rcu_read_unlock();
713 return ret;
714 }
715
716 /*
717 * Start a kernel session by opening all necessary streams.
718 */
719 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
720 {
721 int ret;
722 struct ltt_kernel_channel *kchan;
723
724 /* Open kernel metadata */
725 if (ksess->metadata == NULL && ksess->output_traces) {
726 ret = kernel_open_metadata(ksess);
727 if (ret < 0) {
728 ret = LTTNG_ERR_KERN_META_FAIL;
729 goto error;
730 }
731 }
732
733 /* Open kernel metadata stream */
734 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
735 ret = kernel_open_metadata_stream(ksess);
736 if (ret < 0) {
737 ERR("Kernel create metadata stream failed");
738 ret = LTTNG_ERR_KERN_STREAM_FAIL;
739 goto error;
740 }
741 }
742
743 /* For each channel */
744 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
745 if (kchan->stream_count == 0) {
746 ret = kernel_open_channel_stream(kchan);
747 if (ret < 0) {
748 ret = LTTNG_ERR_KERN_STREAM_FAIL;
749 goto error;
750 }
751 /* Update the stream global counter */
752 ksess->stream_count_global += ret;
753 }
754 }
755
756 /* Setup kernel consumer socket and send fds to it */
757 ret = init_kernel_tracing(ksess);
758 if (ret != 0) {
759 ret = LTTNG_ERR_KERN_START_FAIL;
760 goto error;
761 }
762
763 /* This start the kernel tracing */
764 ret = kernel_start_session(ksess);
765 if (ret < 0) {
766 ret = LTTNG_ERR_KERN_START_FAIL;
767 goto error;
768 }
769
770 /* Quiescent wait after starting trace */
771 kernel_wait_quiescent(kernel_tracer_fd);
772
773 ksess->started = 1;
774
775 ret = LTTNG_OK;
776
777 error:
778 return ret;
779 }
780
781 /*
782 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
783 */
784 int cmd_disable_channel(struct ltt_session *session, int domain,
785 char *channel_name)
786 {
787 int ret;
788 struct ltt_ust_session *usess;
789
790 usess = session->ust_session;
791
792 rcu_read_lock();
793
794 switch (domain) {
795 case LTTNG_DOMAIN_KERNEL:
796 {
797 ret = channel_kernel_disable(session->kernel_session,
798 channel_name);
799 if (ret != LTTNG_OK) {
800 goto error;
801 }
802
803 kernel_wait_quiescent(kernel_tracer_fd);
804 break;
805 }
806 case LTTNG_DOMAIN_UST:
807 {
808 struct ltt_ust_channel *uchan;
809 struct lttng_ht *chan_ht;
810
811 chan_ht = usess->domain_global.channels;
812
813 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
814 if (uchan == NULL) {
815 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
816 goto error;
817 }
818
819 ret = channel_ust_disable(usess, uchan);
820 if (ret != LTTNG_OK) {
821 goto error;
822 }
823 break;
824 }
825 #if 0
826 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
827 case LTTNG_DOMAIN_UST_EXEC_NAME:
828 case LTTNG_DOMAIN_UST_PID:
829 #endif
830 default:
831 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
832 goto error;
833 }
834
835 ret = LTTNG_OK;
836
837 error:
838 rcu_read_unlock();
839 return ret;
840 }
841
842 /*
843 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
844 *
845 * The wpipe arguments is used as a notifier for the kernel thread.
846 */
847 int cmd_enable_channel(struct ltt_session *session,
848 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
849 {
850 int ret;
851 struct ltt_ust_session *usess = session->ust_session;
852 struct lttng_ht *chan_ht;
853
854 assert(session);
855 assert(attr);
856 assert(domain);
857
858 DBG("Enabling channel %s for session %s", attr->name, session->name);
859
860 rcu_read_lock();
861
862 switch (domain->type) {
863 case LTTNG_DOMAIN_KERNEL:
864 {
865 struct ltt_kernel_channel *kchan;
866
867 kchan = trace_kernel_get_channel_by_name(attr->name,
868 session->kernel_session);
869 if (kchan == NULL) {
870 /*
871 * Don't try to create a channel if the session
872 * has been started at some point in time
873 * before. The tracer does not allow it.
874 */
875 if (session->started) {
876 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
877 goto error;
878 }
879 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
880 if (attr->name[0] != '\0') {
881 session->kernel_session->has_non_default_channel = 1;
882 }
883 } else {
884 ret = channel_kernel_enable(session->kernel_session, kchan);
885 }
886
887 if (ret != LTTNG_OK) {
888 goto error;
889 }
890
891 kernel_wait_quiescent(kernel_tracer_fd);
892 break;
893 }
894 case LTTNG_DOMAIN_UST:
895 {
896 struct ltt_ust_channel *uchan;
897
898 chan_ht = usess->domain_global.channels;
899
900 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
901 if (uchan == NULL) {
902 /*
903 * Don't try to create a channel if the session
904 * has been started at some point in time
905 * before. The tracer does not allow it.
906 */
907 if (session->started) {
908 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
909 goto error;
910 }
911 ret = channel_ust_create(usess, attr, domain->buf_type);
912 if (attr->name[0] != '\0') {
913 usess->has_non_default_channel = 1;
914 }
915 } else {
916 ret = channel_ust_enable(usess, uchan);
917 }
918 break;
919 }
920 default:
921 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
922 goto error;
923 }
924
925 error:
926 rcu_read_unlock();
927 return ret;
928 }
929
930
931 /*
932 * Command LTTNG_DISABLE_EVENT processed by the client thread.
933 */
934 int cmd_disable_event(struct ltt_session *session, int domain,
935 char *channel_name, char *event_name)
936 {
937 int ret;
938
939 rcu_read_lock();
940
941 switch (domain) {
942 case LTTNG_DOMAIN_KERNEL:
943 {
944 struct ltt_kernel_channel *kchan;
945 struct ltt_kernel_session *ksess;
946
947 ksess = session->kernel_session;
948
949 /*
950 * If a non-default channel has been created in the
951 * session, explicitely require that -c chan_name needs
952 * to be provided.
953 */
954 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
955 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
956 goto error;
957 }
958
959 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
960 if (kchan == NULL) {
961 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
962 goto error;
963 }
964
965 ret = event_kernel_disable_tracepoint(kchan, event_name);
966 if (ret != LTTNG_OK) {
967 goto error;
968 }
969
970 kernel_wait_quiescent(kernel_tracer_fd);
971 break;
972 }
973 case LTTNG_DOMAIN_UST:
974 {
975 struct ltt_ust_channel *uchan;
976 struct ltt_ust_session *usess;
977
978 usess = session->ust_session;
979
980 /*
981 * If a non-default channel has been created in the
982 * session, explicitely require that -c chan_name needs
983 * to be provided.
984 */
985 if (usess->has_non_default_channel && channel_name[0] == '\0') {
986 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
987 goto error;
988 }
989
990 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
991 channel_name);
992 if (uchan == NULL) {
993 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
994 goto error;
995 }
996
997 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
998 if (ret != LTTNG_OK) {
999 goto error;
1000 }
1001
1002 DBG3("Disable UST event %s in channel %s completed", event_name,
1003 channel_name);
1004 break;
1005 }
1006 #if 0
1007 case LTTNG_DOMAIN_UST_EXEC_NAME:
1008 case LTTNG_DOMAIN_UST_PID:
1009 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1010 #endif
1011 default:
1012 ret = LTTNG_ERR_UND;
1013 goto error;
1014 }
1015
1016 ret = LTTNG_OK;
1017
1018 error:
1019 rcu_read_unlock();
1020 return ret;
1021 }
1022
1023 /*
1024 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
1025 */
1026 int cmd_disable_event_all(struct ltt_session *session, int domain,
1027 char *channel_name)
1028 {
1029 int ret;
1030
1031 rcu_read_lock();
1032
1033 switch (domain) {
1034 case LTTNG_DOMAIN_KERNEL:
1035 {
1036 struct ltt_kernel_session *ksess;
1037 struct ltt_kernel_channel *kchan;
1038
1039 ksess = session->kernel_session;
1040
1041 /*
1042 * If a non-default channel has been created in the
1043 * session, explicitely require that -c chan_name needs
1044 * to be provided.
1045 */
1046 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1047 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1048 goto error;
1049 }
1050
1051 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1052 if (kchan == NULL) {
1053 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1054 goto error;
1055 }
1056
1057 ret = event_kernel_disable_all(kchan);
1058 if (ret != LTTNG_OK) {
1059 goto error;
1060 }
1061
1062 kernel_wait_quiescent(kernel_tracer_fd);
1063 break;
1064 }
1065 case LTTNG_DOMAIN_UST:
1066 {
1067 struct ltt_ust_session *usess;
1068 struct ltt_ust_channel *uchan;
1069
1070 usess = session->ust_session;
1071
1072 /*
1073 * If a non-default channel has been created in the
1074 * session, explicitely require that -c chan_name needs
1075 * to be provided.
1076 */
1077 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1078 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1079 goto error;
1080 }
1081
1082 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1083 channel_name);
1084 if (uchan == NULL) {
1085 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1086 goto error;
1087 }
1088
1089 ret = event_ust_disable_all_tracepoints(usess, uchan);
1090 if (ret != 0) {
1091 goto error;
1092 }
1093
1094 DBG3("Disable all UST events in channel %s completed", channel_name);
1095
1096 break;
1097 }
1098 #if 0
1099 case LTTNG_DOMAIN_UST_EXEC_NAME:
1100 case LTTNG_DOMAIN_UST_PID:
1101 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1102 #endif
1103 default:
1104 ret = LTTNG_ERR_UND;
1105 goto error;
1106 }
1107
1108 ret = LTTNG_OK;
1109
1110 error:
1111 rcu_read_unlock();
1112 return ret;
1113 }
1114
1115 /*
1116 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1117 */
1118 int cmd_add_context(struct ltt_session *session, int domain,
1119 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1120 {
1121 int ret, chan_kern_created = 0, chan_ust_created = 0;
1122
1123 switch (domain) {
1124 case LTTNG_DOMAIN_KERNEL:
1125 assert(session->kernel_session);
1126
1127 /*
1128 * If a non-default channel has been created in the
1129 * session, explicitely require that -c chan_name needs
1130 * to be provided.
1131 */
1132 if (session->kernel_session->has_non_default_channel
1133 && channel_name[0] == '\0') {
1134 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1135 goto error;
1136 }
1137
1138 if (session->kernel_session->channel_count == 0) {
1139 /* Create default channel */
1140 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1141 if (ret != LTTNG_OK) {
1142 goto error;
1143 }
1144 chan_kern_created = 1;
1145 }
1146 /* Add kernel context to kernel tracer */
1147 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1148 if (ret != LTTNG_OK) {
1149 goto error;
1150 }
1151 break;
1152 case LTTNG_DOMAIN_UST:
1153 {
1154 struct ltt_ust_session *usess = session->ust_session;
1155 unsigned int chan_count;
1156
1157 assert(usess);
1158
1159 /*
1160 * If a non-default channel has been created in the
1161 * session, explicitely require that -c chan_name needs
1162 * to be provided.
1163 */
1164 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1165 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1166 goto error;
1167 }
1168
1169 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1170 if (chan_count == 0) {
1171 struct lttng_channel *attr;
1172 /* Create default channel */
1173 attr = channel_new_default_attr(domain, usess->buffer_type);
1174 if (attr == NULL) {
1175 ret = LTTNG_ERR_FATAL;
1176 goto error;
1177 }
1178
1179 ret = channel_ust_create(usess, attr, usess->buffer_type);
1180 if (ret != LTTNG_OK) {
1181 free(attr);
1182 goto error;
1183 }
1184 free(attr);
1185 chan_ust_created = 1;
1186 }
1187
1188 ret = context_ust_add(usess, domain, ctx, channel_name);
1189 if (ret != LTTNG_OK) {
1190 goto error;
1191 }
1192 break;
1193 }
1194 #if 0
1195 case LTTNG_DOMAIN_UST_EXEC_NAME:
1196 case LTTNG_DOMAIN_UST_PID:
1197 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1198 #endif
1199 default:
1200 ret = LTTNG_ERR_UND;
1201 goto error;
1202 }
1203
1204 return LTTNG_OK;
1205
1206 error:
1207 if (chan_kern_created) {
1208 struct ltt_kernel_channel *kchan =
1209 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1210 session->kernel_session);
1211 /* Created previously, this should NOT fail. */
1212 assert(kchan);
1213 kernel_destroy_channel(kchan);
1214 }
1215
1216 if (chan_ust_created) {
1217 struct ltt_ust_channel *uchan =
1218 trace_ust_find_channel_by_name(
1219 session->ust_session->domain_global.channels,
1220 DEFAULT_CHANNEL_NAME);
1221 /* Created previously, this should NOT fail. */
1222 assert(uchan);
1223 /* Remove from the channel list of the session. */
1224 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1225 uchan);
1226 trace_ust_destroy_channel(uchan);
1227 }
1228 return ret;
1229 }
1230
1231 /*
1232 * Command LTTNG_ENABLE_EVENT processed by the client thread.
1233 */
1234 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1235 char *channel_name, struct lttng_event *event,
1236 struct lttng_filter_bytecode *filter, int wpipe)
1237 {
1238 int ret, channel_created = 0;
1239 struct lttng_channel *attr;
1240
1241 assert(session);
1242 assert(event);
1243 assert(channel_name);
1244
1245 rcu_read_lock();
1246
1247 switch (domain->type) {
1248 case LTTNG_DOMAIN_KERNEL:
1249 {
1250 struct ltt_kernel_channel *kchan;
1251
1252 /*
1253 * If a non-default channel has been created in the
1254 * session, explicitely require that -c chan_name needs
1255 * to be provided.
1256 */
1257 if (session->kernel_session->has_non_default_channel
1258 && channel_name[0] == '\0') {
1259 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1260 goto error;
1261 }
1262
1263 kchan = trace_kernel_get_channel_by_name(channel_name,
1264 session->kernel_session);
1265 if (kchan == NULL) {
1266 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1267 LTTNG_BUFFER_GLOBAL);
1268 if (attr == NULL) {
1269 ret = LTTNG_ERR_FATAL;
1270 goto error;
1271 }
1272 strncpy(attr->name, channel_name, sizeof(attr->name));
1273
1274 ret = cmd_enable_channel(session, domain, attr, wpipe);
1275 if (ret != LTTNG_OK) {
1276 free(attr);
1277 goto error;
1278 }
1279 free(attr);
1280
1281 channel_created = 1;
1282 }
1283
1284 /* Get the newly created kernel channel pointer */
1285 kchan = trace_kernel_get_channel_by_name(channel_name,
1286 session->kernel_session);
1287 if (kchan == NULL) {
1288 /* This sould not happen... */
1289 ret = LTTNG_ERR_FATAL;
1290 goto error;
1291 }
1292
1293 ret = event_kernel_enable_tracepoint(kchan, event);
1294 if (ret != LTTNG_OK) {
1295 if (channel_created) {
1296 /* Let's not leak a useless channel. */
1297 kernel_destroy_channel(kchan);
1298 }
1299 goto error;
1300 }
1301
1302 kernel_wait_quiescent(kernel_tracer_fd);
1303 break;
1304 }
1305 case LTTNG_DOMAIN_UST:
1306 {
1307 struct ltt_ust_channel *uchan;
1308 struct ltt_ust_session *usess = session->ust_session;
1309
1310 assert(usess);
1311
1312 /*
1313 * If a non-default channel has been created in the
1314 * session, explicitely require that -c chan_name needs
1315 * to be provided.
1316 */
1317 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1318 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1319 goto error;
1320 }
1321
1322 /* Get channel from global UST domain */
1323 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1324 channel_name);
1325 if (uchan == NULL) {
1326 /* Create default channel */
1327 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1328 usess->buffer_type);
1329 if (attr == NULL) {
1330 ret = LTTNG_ERR_FATAL;
1331 goto error;
1332 }
1333 strncpy(attr->name, channel_name, sizeof(attr->name));
1334
1335 ret = cmd_enable_channel(session, domain, attr, wpipe);
1336 if (ret != LTTNG_OK) {
1337 free(attr);
1338 goto error;
1339 }
1340 free(attr);
1341
1342 /* Get the newly created channel reference back */
1343 uchan = trace_ust_find_channel_by_name(
1344 usess->domain_global.channels, channel_name);
1345 assert(uchan);
1346 }
1347
1348 /* At this point, the session and channel exist on the tracer */
1349 ret = event_ust_enable_tracepoint(usess, uchan, event, filter);
1350 if (ret != LTTNG_OK) {
1351 goto error;
1352 }
1353 break;
1354 }
1355 #if 0
1356 case LTTNG_DOMAIN_UST_EXEC_NAME:
1357 case LTTNG_DOMAIN_UST_PID:
1358 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1359 #endif
1360 default:
1361 ret = LTTNG_ERR_UND;
1362 goto error;
1363 }
1364
1365 ret = LTTNG_OK;
1366
1367 error:
1368 rcu_read_unlock();
1369 return ret;
1370 }
1371
1372 /*
1373 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
1374 */
1375 int cmd_enable_event_all(struct ltt_session *session,
1376 struct lttng_domain *domain, char *channel_name, int event_type,
1377 struct lttng_filter_bytecode *filter, int wpipe)
1378 {
1379 int ret;
1380 struct lttng_channel *attr;
1381
1382 assert(session);
1383 assert(channel_name);
1384
1385 rcu_read_lock();
1386
1387 switch (domain->type) {
1388 case LTTNG_DOMAIN_KERNEL:
1389 {
1390 struct ltt_kernel_channel *kchan;
1391
1392 assert(session->kernel_session);
1393
1394 /*
1395 * If a non-default channel has been created in the
1396 * session, explicitely require that -c chan_name needs
1397 * to be provided.
1398 */
1399 if (session->kernel_session->has_non_default_channel
1400 && channel_name[0] == '\0') {
1401 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1402 goto error;
1403 }
1404
1405 kchan = trace_kernel_get_channel_by_name(channel_name,
1406 session->kernel_session);
1407 if (kchan == NULL) {
1408 /* Create default channel */
1409 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1410 LTTNG_BUFFER_GLOBAL);
1411 if (attr == NULL) {
1412 ret = LTTNG_ERR_FATAL;
1413 goto error;
1414 }
1415 strncpy(attr->name, channel_name, sizeof(attr->name));
1416
1417 ret = cmd_enable_channel(session, domain, attr, wpipe);
1418 if (ret != LTTNG_OK) {
1419 free(attr);
1420 goto error;
1421 }
1422 free(attr);
1423
1424 /* Get the newly created kernel channel pointer */
1425 kchan = trace_kernel_get_channel_by_name(channel_name,
1426 session->kernel_session);
1427 assert(kchan);
1428 }
1429
1430 switch (event_type) {
1431 case LTTNG_EVENT_SYSCALL:
1432 ret = event_kernel_enable_all_syscalls(kchan, kernel_tracer_fd);
1433 break;
1434 case LTTNG_EVENT_TRACEPOINT:
1435 /*
1436 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
1437 * events already registered to the channel.
1438 */
1439 ret = event_kernel_enable_all_tracepoints(kchan, kernel_tracer_fd);
1440 break;
1441 case LTTNG_EVENT_ALL:
1442 /* Enable syscalls and tracepoints */
1443 ret = event_kernel_enable_all(kchan, kernel_tracer_fd);
1444 break;
1445 default:
1446 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1447 goto error;
1448 }
1449
1450 /* Manage return value */
1451 if (ret != LTTNG_OK) {
1452 /*
1453 * On error, cmd_enable_channel call will take care of destroying
1454 * the created channel if it was needed.
1455 */
1456 goto error;
1457 }
1458
1459 kernel_wait_quiescent(kernel_tracer_fd);
1460 break;
1461 }
1462 case LTTNG_DOMAIN_UST:
1463 {
1464 struct ltt_ust_channel *uchan;
1465 struct ltt_ust_session *usess = session->ust_session;
1466
1467 assert(usess);
1468
1469 /*
1470 * If a non-default channel has been created in the
1471 * session, explicitely require that -c chan_name needs
1472 * to be provided.
1473 */
1474 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1475 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1476 goto error;
1477 }
1478
1479 /* Get channel from global UST domain */
1480 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1481 channel_name);
1482 if (uchan == NULL) {
1483 /* Create default channel */
1484 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1485 usess->buffer_type);
1486 if (attr == NULL) {
1487 ret = LTTNG_ERR_FATAL;
1488 goto error;
1489 }
1490 strncpy(attr->name, channel_name, sizeof(attr->name));
1491
1492 ret = cmd_enable_channel(session, domain, attr, wpipe);
1493 if (ret != LTTNG_OK) {
1494 free(attr);
1495 goto error;
1496 }
1497 free(attr);
1498
1499 /* Get the newly created channel reference back */
1500 uchan = trace_ust_find_channel_by_name(
1501 usess->domain_global.channels, channel_name);
1502 assert(uchan);
1503 }
1504
1505 /* At this point, the session and channel exist on the tracer */
1506
1507 switch (event_type) {
1508 case LTTNG_EVENT_ALL:
1509 case LTTNG_EVENT_TRACEPOINT:
1510 ret = event_ust_enable_all_tracepoints(usess, uchan, filter);
1511 if (ret != LTTNG_OK) {
1512 goto error;
1513 }
1514 break;
1515 default:
1516 ret = LTTNG_ERR_UST_ENABLE_FAIL;
1517 goto error;
1518 }
1519
1520 /* Manage return value */
1521 if (ret != LTTNG_OK) {
1522 goto error;
1523 }
1524
1525 break;
1526 }
1527 #if 0
1528 case LTTNG_DOMAIN_UST_EXEC_NAME:
1529 case LTTNG_DOMAIN_UST_PID:
1530 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1531 #endif
1532 default:
1533 ret = LTTNG_ERR_UND;
1534 goto error;
1535 }
1536
1537 ret = LTTNG_OK;
1538
1539 error:
1540 rcu_read_unlock();
1541 return ret;
1542 }
1543
1544
1545 /*
1546 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1547 */
1548 ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
1549 {
1550 int ret;
1551 ssize_t nb_events = 0;
1552
1553 switch (domain) {
1554 case LTTNG_DOMAIN_KERNEL:
1555 nb_events = kernel_list_events(kernel_tracer_fd, events);
1556 if (nb_events < 0) {
1557 ret = LTTNG_ERR_KERN_LIST_FAIL;
1558 goto error;
1559 }
1560 break;
1561 case LTTNG_DOMAIN_UST:
1562 nb_events = ust_app_list_events(events);
1563 if (nb_events < 0) {
1564 ret = LTTNG_ERR_UST_LIST_FAIL;
1565 goto error;
1566 }
1567 break;
1568 default:
1569 ret = LTTNG_ERR_UND;
1570 goto error;
1571 }
1572
1573 return nb_events;
1574
1575 error:
1576 /* Return negative value to differentiate return code */
1577 return -ret;
1578 }
1579
1580 /*
1581 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1582 */
1583 ssize_t cmd_list_tracepoint_fields(int domain,
1584 struct lttng_event_field **fields)
1585 {
1586 int ret;
1587 ssize_t nb_fields = 0;
1588
1589 switch (domain) {
1590 case LTTNG_DOMAIN_UST:
1591 nb_fields = ust_app_list_event_fields(fields);
1592 if (nb_fields < 0) {
1593 ret = LTTNG_ERR_UST_LIST_FAIL;
1594 goto error;
1595 }
1596 break;
1597 case LTTNG_DOMAIN_KERNEL:
1598 default: /* fall-through */
1599 ret = LTTNG_ERR_UND;
1600 goto error;
1601 }
1602
1603 return nb_fields;
1604
1605 error:
1606 /* Return negative value to differentiate return code */
1607 return -ret;
1608 }
1609
1610 /*
1611 * Command LTTNG_START_TRACE processed by the client thread.
1612 */
1613 int cmd_start_trace(struct ltt_session *session)
1614 {
1615 int ret;
1616 struct ltt_kernel_session *ksession;
1617 struct ltt_ust_session *usess;
1618
1619 assert(session);
1620
1621 /* Ease our life a bit ;) */
1622 ksession = session->kernel_session;
1623 usess = session->ust_session;
1624
1625 if (session->enabled) {
1626 /* Already started. */
1627 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1628 goto error;
1629 }
1630
1631 session->enabled = 1;
1632
1633 /* Kernel tracing */
1634 if (ksession != NULL) {
1635 ret = start_kernel_session(ksession, kernel_tracer_fd);
1636 if (ret != LTTNG_OK) {
1637 goto error;
1638 }
1639 }
1640
1641 /* Flag session that trace should start automatically */
1642 if (usess) {
1643 usess->start_trace = 1;
1644
1645 ret = ust_app_start_trace_all(usess);
1646 if (ret < 0) {
1647 ret = LTTNG_ERR_UST_START_FAIL;
1648 goto error;
1649 }
1650 }
1651
1652 session->started = 1;
1653
1654 ret = LTTNG_OK;
1655
1656 error:
1657 return ret;
1658 }
1659
1660 /*
1661 * Command LTTNG_STOP_TRACE processed by the client thread.
1662 */
1663 int cmd_stop_trace(struct ltt_session *session)
1664 {
1665 int ret;
1666 struct ltt_kernel_channel *kchan;
1667 struct ltt_kernel_session *ksession;
1668 struct ltt_ust_session *usess;
1669
1670 assert(session);
1671
1672 /* Short cut */
1673 ksession = session->kernel_session;
1674 usess = session->ust_session;
1675
1676 if (!session->enabled) {
1677 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
1678 goto error;
1679 }
1680
1681 session->enabled = 0;
1682
1683 /* Kernel tracer */
1684 if (ksession && ksession->started) {
1685 DBG("Stop kernel tracing");
1686
1687 /* Flush metadata if exist */
1688 if (ksession->metadata_stream_fd >= 0) {
1689 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
1690 if (ret < 0) {
1691 ERR("Kernel metadata flush failed");
1692 }
1693 }
1694
1695 /* Flush all buffers before stopping */
1696 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
1697 ret = kernel_flush_buffer(kchan);
1698 if (ret < 0) {
1699 ERR("Kernel flush buffer error");
1700 }
1701 }
1702
1703 ret = kernel_stop_session(ksession);
1704 if (ret < 0) {
1705 ret = LTTNG_ERR_KERN_STOP_FAIL;
1706 goto error;
1707 }
1708
1709 kernel_wait_quiescent(kernel_tracer_fd);
1710
1711 ksession->started = 0;
1712 }
1713
1714 if (usess && usess->start_trace) {
1715 usess->start_trace = 0;
1716
1717 ret = ust_app_stop_trace_all(usess);
1718 if (ret < 0) {
1719 ret = LTTNG_ERR_UST_STOP_FAIL;
1720 goto error;
1721 }
1722 }
1723
1724 ret = LTTNG_OK;
1725
1726 error:
1727 return ret;
1728 }
1729
1730 /*
1731 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
1732 */
1733 int cmd_set_consumer_uri(int domain, struct ltt_session *session,
1734 size_t nb_uri, struct lttng_uri *uris)
1735 {
1736 int ret, i;
1737 struct ltt_kernel_session *ksess = session->kernel_session;
1738 struct ltt_ust_session *usess = session->ust_session;
1739 struct consumer_output *consumer = NULL;
1740
1741 assert(session);
1742 assert(uris);
1743 assert(nb_uri > 0);
1744
1745 /* Can't enable consumer after session started. */
1746 if (session->enabled) {
1747 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1748 goto error;
1749 }
1750
1751 /*
1752 * This case switch makes sure the domain session has a temporary consumer
1753 * so the URL can be set.
1754 */
1755 switch (domain) {
1756 case 0:
1757 /* Code flow error. A session MUST always have a consumer object */
1758 assert(session->consumer);
1759 /*
1760 * The URL will be added to the tracing session consumer instead of a
1761 * specific domain consumer.
1762 */
1763 consumer = session->consumer;
1764 break;
1765 case LTTNG_DOMAIN_KERNEL:
1766 /* Code flow error if we don't have a kernel session here. */
1767 assert(ksess);
1768 assert(ksess->consumer);
1769 consumer = ksess->consumer;
1770 break;
1771 case LTTNG_DOMAIN_UST:
1772 /* Code flow error if we don't have a kernel session here. */
1773 assert(usess);
1774 assert(usess->consumer);
1775 consumer = usess->consumer;
1776 break;
1777 }
1778
1779 for (i = 0; i < nb_uri; i++) {
1780 ret = add_uri_to_consumer(consumer, &uris[i], domain, session->name);
1781 if (ret != LTTNG_OK) {
1782 goto error;
1783 }
1784 }
1785
1786 /* All good! */
1787 ret = LTTNG_OK;
1788
1789 error:
1790 return ret;
1791 }
1792
1793 /*
1794 * Command LTTNG_CREATE_SESSION processed by the client thread.
1795 */
1796 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
1797 size_t nb_uri, lttng_sock_cred *creds)
1798 {
1799 int ret;
1800 struct ltt_session *session;
1801
1802 assert(name);
1803 assert(creds);
1804
1805 /*
1806 * Verify if the session already exist
1807 *
1808 * XXX: There is no need for the session lock list here since the caller
1809 * (process_client_msg) is holding it. We might want to change that so a
1810 * single command does not lock the entire session list.
1811 */
1812 session = session_find_by_name(name);
1813 if (session != NULL) {
1814 ret = LTTNG_ERR_EXIST_SESS;
1815 goto find_error;
1816 }
1817
1818 /* Create tracing session in the registry */
1819 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
1820 LTTNG_SOCK_GET_GID_CRED(creds));
1821 if (ret != LTTNG_OK) {
1822 goto session_error;
1823 }
1824
1825 /*
1826 * Get the newly created session pointer back
1827 *
1828 * XXX: There is no need for the session lock list here since the caller
1829 * (process_client_msg) is holding it. We might want to change that so a
1830 * single command does not lock the entire session list.
1831 */
1832 session = session_find_by_name(name);
1833 assert(session);
1834
1835 /* Create default consumer output for the session not yet created. */
1836 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
1837 if (session->consumer == NULL) {
1838 ret = LTTNG_ERR_FATAL;
1839 goto consumer_error;
1840 }
1841
1842 if (uris) {
1843 ret = cmd_set_consumer_uri(0, session, nb_uri, uris);
1844 if (ret != LTTNG_OK) {
1845 goto consumer_error;
1846 }
1847 session->output_traces = 1;
1848 } else {
1849 session->output_traces = 0;
1850 DBG2("Session %s created with no output", session->name);
1851 }
1852
1853 session->consumer->enabled = 1;
1854
1855 return LTTNG_OK;
1856
1857 consumer_error:
1858 session_destroy(session);
1859 session_error:
1860 find_error:
1861 return ret;
1862 }
1863
1864 /*
1865 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
1866 */
1867 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
1868 size_t nb_uri, lttng_sock_cred *creds)
1869 {
1870 int ret;
1871 struct ltt_session *session;
1872 struct snapshot_output *new_output = NULL;
1873
1874 assert(name);
1875 assert(creds);
1876
1877 /*
1878 * Create session in no output mode with URIs set to NULL. The uris we've
1879 * received are for a default snapshot output if one.
1880 */
1881 ret = cmd_create_session_uri(name, NULL, 0, creds);
1882 if (ret != LTTNG_OK) {
1883 goto error;
1884 }
1885
1886 /* Get the newly created session pointer back. This should NEVER fail. */
1887 session = session_find_by_name(name);
1888 assert(session);
1889
1890 /* Flag session for snapshot mode. */
1891 session->snapshot_mode = 1;
1892
1893 /* Skip snapshot output creation if no URI is given. */
1894 if (nb_uri == 0) {
1895 goto end;
1896 }
1897
1898 new_output = snapshot_output_alloc();
1899 if (!new_output) {
1900 ret = LTTNG_ERR_NOMEM;
1901 goto error_snapshot_alloc;
1902 }
1903
1904 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
1905 uris, nb_uri, session->consumer, new_output, &session->snapshot);
1906 if (ret < 0) {
1907 if (ret == -ENOMEM) {
1908 ret = LTTNG_ERR_NOMEM;
1909 } else {
1910 ret = LTTNG_ERR_INVALID;
1911 }
1912 goto error_snapshot;
1913 }
1914
1915 rcu_read_lock();
1916 snapshot_add_output(&session->snapshot, new_output);
1917 rcu_read_unlock();
1918
1919 end:
1920 return LTTNG_OK;
1921
1922 error_snapshot:
1923 snapshot_output_destroy(new_output);
1924 error_snapshot_alloc:
1925 session_destroy(session);
1926 error:
1927 return ret;
1928 }
1929
1930 /*
1931 * Command LTTNG_DESTROY_SESSION processed by the client thread.
1932 */
1933 int cmd_destroy_session(struct ltt_session *session, int wpipe)
1934 {
1935 int ret;
1936 struct ltt_ust_session *usess;
1937 struct ltt_kernel_session *ksess;
1938
1939 /* Safety net */
1940 assert(session);
1941
1942 usess = session->ust_session;
1943 ksess = session->kernel_session;
1944
1945 /* Clean kernel session teardown */
1946 kernel_destroy_session(ksess);
1947
1948 /* UST session teardown */
1949 if (usess) {
1950 /* Close any relayd session */
1951 consumer_output_send_destroy_relayd(usess->consumer);
1952
1953 /* Destroy every UST application related to this session. */
1954 ret = ust_app_destroy_trace_all(usess);
1955 if (ret) {
1956 ERR("Error in ust_app_destroy_trace_all");
1957 }
1958
1959 /* Clean up the rest. */
1960 trace_ust_destroy_session(usess);
1961 }
1962
1963 /*
1964 * Must notify the kernel thread here to update it's poll set in order to
1965 * remove the channel(s)' fd just destroyed.
1966 */
1967 ret = notify_thread_pipe(wpipe);
1968 if (ret < 0) {
1969 PERROR("write kernel poll pipe");
1970 }
1971
1972 ret = session_destroy(session);
1973
1974 return ret;
1975 }
1976
1977 /*
1978 * Command LTTNG_CALIBRATE processed by the client thread.
1979 */
1980 int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
1981 {
1982 int ret;
1983
1984 switch (domain) {
1985 case LTTNG_DOMAIN_KERNEL:
1986 {
1987 struct lttng_kernel_calibrate kcalibrate;
1988
1989 kcalibrate.type = calibrate->type;
1990 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
1991 if (ret < 0) {
1992 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1993 goto error;
1994 }
1995 break;
1996 }
1997 case LTTNG_DOMAIN_UST:
1998 {
1999 struct lttng_ust_calibrate ucalibrate;
2000
2001 ucalibrate.type = calibrate->type;
2002 ret = ust_app_calibrate_glb(&ucalibrate);
2003 if (ret < 0) {
2004 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
2005 goto error;
2006 }
2007 break;
2008 }
2009 default:
2010 ret = LTTNG_ERR_UND;
2011 goto error;
2012 }
2013
2014 ret = LTTNG_OK;
2015
2016 error:
2017 return ret;
2018 }
2019
2020 /*
2021 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2022 */
2023 int cmd_register_consumer(struct ltt_session *session, int domain,
2024 const char *sock_path, struct consumer_data *cdata)
2025 {
2026 int ret, sock;
2027 struct consumer_socket *socket = NULL;
2028
2029 assert(session);
2030 assert(cdata);
2031 assert(sock_path);
2032
2033 switch (domain) {
2034 case LTTNG_DOMAIN_KERNEL:
2035 {
2036 struct ltt_kernel_session *ksess = session->kernel_session;
2037
2038 assert(ksess);
2039
2040 /* Can't register a consumer if there is already one */
2041 if (ksess->consumer_fds_sent != 0) {
2042 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2043 goto error;
2044 }
2045
2046 sock = lttcomm_connect_unix_sock(sock_path);
2047 if (sock < 0) {
2048 ret = LTTNG_ERR_CONNECT_FAIL;
2049 goto error;
2050 }
2051
2052 socket = consumer_allocate_socket(sock);
2053 if (socket == NULL) {
2054 ret = close(sock);
2055 if (ret < 0) {
2056 PERROR("close register consumer");
2057 }
2058 ret = LTTNG_ERR_FATAL;
2059 goto error;
2060 }
2061
2062 socket->lock = zmalloc(sizeof(pthread_mutex_t));
2063 if (socket->lock == NULL) {
2064 PERROR("zmalloc pthread mutex");
2065 ret = LTTNG_ERR_FATAL;
2066 goto error;
2067 }
2068 pthread_mutex_init(socket->lock, NULL);
2069 socket->registered = 1;
2070
2071 rcu_read_lock();
2072 consumer_add_socket(socket, ksess->consumer);
2073 rcu_read_unlock();
2074
2075 pthread_mutex_lock(&cdata->pid_mutex);
2076 cdata->pid = -1;
2077 pthread_mutex_unlock(&cdata->pid_mutex);
2078
2079 break;
2080 }
2081 default:
2082 /* TODO: Userspace tracing */
2083 ret = LTTNG_ERR_UND;
2084 goto error;
2085 }
2086
2087 return LTTNG_OK;
2088
2089 error:
2090 if (socket) {
2091 consumer_destroy_socket(socket);
2092 }
2093 return ret;
2094 }
2095
2096 /*
2097 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2098 */
2099 ssize_t cmd_list_domains(struct ltt_session *session,
2100 struct lttng_domain **domains)
2101 {
2102 int ret, index = 0;
2103 ssize_t nb_dom = 0;
2104
2105 if (session->kernel_session != NULL) {
2106 DBG3("Listing domains found kernel domain");
2107 nb_dom++;
2108 }
2109
2110 if (session->ust_session != NULL) {
2111 DBG3("Listing domains found UST global domain");
2112 nb_dom++;
2113 }
2114
2115 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2116 if (*domains == NULL) {
2117 ret = LTTNG_ERR_FATAL;
2118 goto error;
2119 }
2120
2121 if (session->kernel_session != NULL) {
2122 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2123 index++;
2124 }
2125
2126 if (session->ust_session != NULL) {
2127 (*domains)[index].type = LTTNG_DOMAIN_UST;
2128 (*domains)[index].buf_type = session->ust_session->buffer_type;
2129 index++;
2130 }
2131
2132 return nb_dom;
2133
2134 error:
2135 /* Return negative value to differentiate return code */
2136 return -ret;
2137 }
2138
2139
2140 /*
2141 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2142 */
2143 ssize_t cmd_list_channels(int domain, struct ltt_session *session,
2144 struct lttng_channel **channels)
2145 {
2146 int ret;
2147 ssize_t nb_chan = 0;
2148
2149 switch (domain) {
2150 case LTTNG_DOMAIN_KERNEL:
2151 if (session->kernel_session != NULL) {
2152 nb_chan = session->kernel_session->channel_count;
2153 }
2154 DBG3("Number of kernel channels %zd", nb_chan);
2155 if (nb_chan <= 0) {
2156 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
2157 }
2158 break;
2159 case LTTNG_DOMAIN_UST:
2160 if (session->ust_session != NULL) {
2161 nb_chan = lttng_ht_get_count(
2162 session->ust_session->domain_global.channels);
2163 }
2164 DBG3("Number of UST global channels %zd", nb_chan);
2165 if (nb_chan <= 0) {
2166 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2167 }
2168 break;
2169 default:
2170 *channels = NULL;
2171 ret = LTTNG_ERR_UND;
2172 goto error;
2173 }
2174
2175 if (nb_chan > 0) {
2176 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
2177 if (*channels == NULL) {
2178 ret = LTTNG_ERR_FATAL;
2179 goto error;
2180 }
2181
2182 list_lttng_channels(domain, session, *channels);
2183 } else {
2184 *channels = NULL;
2185 /* Ret value was set in the domain switch case */
2186 goto error;
2187 }
2188
2189 return nb_chan;
2190
2191 error:
2192 /* Return negative value to differentiate return code */
2193 return -ret;
2194 }
2195
2196 /*
2197 * Command LTTNG_LIST_EVENTS processed by the client thread.
2198 */
2199 ssize_t cmd_list_events(int domain, struct ltt_session *session,
2200 char *channel_name, struct lttng_event **events)
2201 {
2202 int ret = 0;
2203 ssize_t nb_event = 0;
2204
2205 switch (domain) {
2206 case LTTNG_DOMAIN_KERNEL:
2207 if (session->kernel_session != NULL) {
2208 nb_event = list_lttng_kernel_events(channel_name,
2209 session->kernel_session, events);
2210 }
2211 break;
2212 case LTTNG_DOMAIN_UST:
2213 {
2214 if (session->ust_session != NULL) {
2215 nb_event = list_lttng_ust_global_events(channel_name,
2216 &session->ust_session->domain_global, events);
2217 }
2218 break;
2219 }
2220 default:
2221 ret = LTTNG_ERR_UND;
2222 goto error;
2223 }
2224
2225 return nb_event;
2226
2227 error:
2228 /* Return negative value to differentiate return code */
2229 return -ret;
2230 }
2231
2232 /*
2233 * Using the session list, filled a lttng_session array to send back to the
2234 * client for session listing.
2235 *
2236 * The session list lock MUST be acquired before calling this function. Use
2237 * session_lock_list() and session_unlock_list().
2238 */
2239 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2240 gid_t gid)
2241 {
2242 int ret;
2243 unsigned int i = 0;
2244 struct ltt_session *session;
2245 struct ltt_session_list *list = session_get_list();
2246
2247 DBG("Getting all available session for UID %d GID %d",
2248 uid, gid);
2249 /*
2250 * Iterate over session list and append data after the control struct in
2251 * the buffer.
2252 */
2253 cds_list_for_each_entry(session, &list->head, list) {
2254 /*
2255 * Only list the sessions the user can control.
2256 */
2257 if (!session_access_ok(session, uid, gid)) {
2258 continue;
2259 }
2260
2261 struct ltt_kernel_session *ksess = session->kernel_session;
2262 struct ltt_ust_session *usess = session->ust_session;
2263
2264 if (session->consumer->type == CONSUMER_DST_NET ||
2265 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2266 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2267 ret = build_network_session_path(sessions[i].path,
2268 sizeof(sessions[i].path), session);
2269 } else {
2270 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
2271 session->consumer->dst.trace_path);
2272 }
2273 if (ret < 0) {
2274 PERROR("snprintf session path");
2275 continue;
2276 }
2277
2278 strncpy(sessions[i].name, session->name, NAME_MAX);
2279 sessions[i].name[NAME_MAX - 1] = '\0';
2280 sessions[i].enabled = session->enabled;
2281 sessions[i].snapshot_mode = session->snapshot_mode;
2282 i++;
2283 }
2284 }
2285
2286 /*
2287 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2288 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
2289 */
2290 int cmd_data_pending(struct ltt_session *session)
2291 {
2292 int ret;
2293 struct ltt_kernel_session *ksess = session->kernel_session;
2294 struct ltt_ust_session *usess = session->ust_session;
2295
2296 assert(session);
2297
2298 /* Session MUST be stopped to ask for data availability. */
2299 if (session->enabled) {
2300 ret = LTTNG_ERR_SESSION_STARTED;
2301 goto error;
2302 }
2303
2304 if (ksess && ksess->consumer) {
2305 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2306 if (ret == 1) {
2307 /* Data is still being extracted for the kernel. */
2308 goto error;
2309 }
2310 }
2311
2312 if (usess && usess->consumer) {
2313 ret = consumer_is_data_pending(usess->id, usess->consumer);
2314 if (ret == 1) {
2315 /* Data is still being extracted for the kernel. */
2316 goto error;
2317 }
2318 }
2319
2320 /* Data is ready to be read by a viewer */
2321 ret = 0;
2322
2323 error:
2324 return ret;
2325 }
2326
2327 /*
2328 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
2329 *
2330 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2331 */
2332 int cmd_snapshot_add_output(struct ltt_session *session,
2333 struct lttng_snapshot_output *output, uint32_t *id)
2334 {
2335 int ret;
2336 struct snapshot_output *new_output;
2337
2338 assert(session);
2339 assert(output);
2340
2341 DBG("Cmd snapshot add output for session %s", session->name);
2342
2343 /*
2344 * Permission denied to create an output if the session is not
2345 * set in no output mode.
2346 */
2347 if (session->output_traces) {
2348 ret = LTTNG_ERR_EPERM;
2349 goto error;
2350 }
2351
2352 /* Only one output is allowed until we have the "tee" feature. */
2353 if (session->snapshot.nb_output == 1) {
2354 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
2355 goto error;
2356 }
2357
2358 new_output = snapshot_output_alloc();
2359 if (!new_output) {
2360 ret = LTTNG_ERR_NOMEM;
2361 goto error;
2362 }
2363
2364 ret = snapshot_output_init(output->max_size, output->name,
2365 output->ctrl_url, output->data_url, session->consumer, new_output,
2366 &session->snapshot);
2367 if (ret < 0) {
2368 if (ret == -ENOMEM) {
2369 ret = LTTNG_ERR_NOMEM;
2370 } else {
2371 ret = LTTNG_ERR_INVALID;
2372 }
2373 goto free_error;
2374 }
2375
2376 rcu_read_lock();
2377 snapshot_add_output(&session->snapshot, new_output);
2378 if (id) {
2379 *id = new_output->id;
2380 }
2381 rcu_read_unlock();
2382
2383 return LTTNG_OK;
2384
2385 free_error:
2386 snapshot_output_destroy(new_output);
2387 error:
2388 return ret;
2389 }
2390
2391 /*
2392 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
2393 *
2394 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2395 */
2396 int cmd_snapshot_del_output(struct ltt_session *session,
2397 struct lttng_snapshot_output *output)
2398 {
2399 int ret;
2400 struct snapshot_output *sout = NULL;
2401
2402 assert(session);
2403 assert(output);
2404
2405 rcu_read_lock();
2406
2407 /*
2408 * Permission denied to create an output if the session is not
2409 * set in no output mode.
2410 */
2411 if (session->output_traces) {
2412 ret = LTTNG_ERR_EPERM;
2413 goto error;
2414 }
2415
2416 if (output->id) {
2417 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
2418 session->name);
2419 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
2420 } else if (*output->name != '\0') {
2421 DBG("Cmd snapshot del output name %s for session %s", output->name,
2422 session->name);
2423 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
2424 }
2425 if (!sout) {
2426 ret = LTTNG_ERR_INVALID;
2427 goto error;
2428 }
2429
2430 snapshot_delete_output(&session->snapshot, sout);
2431 snapshot_output_destroy(sout);
2432 ret = LTTNG_OK;
2433
2434 error:
2435 rcu_read_unlock();
2436 return ret;
2437 }
2438
2439 /*
2440 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
2441 *
2442 * If no output is available, outputs is untouched and 0 is returned.
2443 *
2444 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
2445 */
2446 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
2447 struct lttng_snapshot_output **outputs)
2448 {
2449 int ret, idx = 0;
2450 struct lttng_snapshot_output *list;
2451 struct lttng_ht_iter iter;
2452 struct snapshot_output *output;
2453
2454 assert(session);
2455 assert(outputs);
2456
2457 DBG("Cmd snapshot list outputs for session %s", session->name);
2458
2459 /*
2460 * Permission denied to create an output if the session is not
2461 * set in no output mode.
2462 */
2463 if (session->output_traces) {
2464 ret = LTTNG_ERR_EPERM;
2465 goto error;
2466 }
2467
2468 if (session->snapshot.nb_output == 0) {
2469 ret = 0;
2470 goto error;
2471 }
2472
2473 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
2474 if (!list) {
2475 ret = LTTNG_ERR_NOMEM;
2476 goto error;
2477 }
2478
2479 /* Copy list from session to the new list object. */
2480 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
2481 output, node.node) {
2482 assert(output->consumer);
2483 list[idx].id = output->id;
2484 list[idx].max_size = output->max_size;
2485 strncpy(list[idx].name, output->name, sizeof(list[idx].name));
2486 if (output->consumer->type == CONSUMER_DST_LOCAL) {
2487 strncpy(list[idx].ctrl_url, output->consumer->dst.trace_path,
2488 sizeof(list[idx].ctrl_url));
2489 } else {
2490 /* Control URI. */
2491 ret = uri_to_str_url(&output->consumer->dst.net.control,
2492 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
2493 if (ret < 0) {
2494 ret = LTTNG_ERR_NOMEM;
2495 goto free_error;
2496 }
2497
2498 /* Data URI. */
2499 ret = uri_to_str_url(&output->consumer->dst.net.data,
2500 list[idx].data_url, sizeof(list[idx].data_url));
2501 if (ret < 0) {
2502 ret = LTTNG_ERR_NOMEM;
2503 goto free_error;
2504 }
2505 }
2506 idx++;
2507 }
2508
2509 *outputs = list;
2510 return session->snapshot.nb_output;
2511
2512 free_error:
2513 free(list);
2514 error:
2515 return -ret;
2516 }
2517
2518 /*
2519 * Send relayd sockets from snapshot output to consumer. Ignore request if the
2520 * snapshot output is *not* set with a remote destination.
2521 *
2522 * Return 0 on success or a LTTNG_ERR code.
2523 */
2524 static int set_relayd_for_snapshot(struct consumer_output *consumer,
2525 struct snapshot_output *snap_output, struct ltt_session *session)
2526 {
2527 int ret = LTTNG_OK;
2528 struct lttng_ht_iter iter;
2529 struct consumer_socket *socket;
2530
2531 assert(consumer);
2532 assert(snap_output);
2533 assert(session);
2534
2535 DBG2("Set relayd object from snapshot output");
2536
2537 /* Ignore if snapshot consumer output is not network. */
2538 if (snap_output->consumer->type != CONSUMER_DST_NET) {
2539 goto error;
2540 }
2541
2542 /*
2543 * For each consumer socket, create and send the relayd object of the
2544 * snapshot output.
2545 */
2546 rcu_read_lock();
2547 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
2548 socket, node.node) {
2549 ret = send_consumer_relayd_sockets(0, session->id,
2550 snap_output->consumer, socket);
2551 if (ret != LTTNG_OK) {
2552 rcu_read_unlock();
2553 goto error;
2554 }
2555 }
2556 rcu_read_unlock();
2557
2558 error:
2559 return ret;
2560 }
2561
2562 /*
2563 * Record a kernel snapshot.
2564 *
2565 * Return 0 on success or a LTTNG_ERR code.
2566 */
2567 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
2568 struct snapshot_output *output, struct ltt_session *session,
2569 int wait, int nb_streams)
2570 {
2571 int ret;
2572
2573 assert(ksess);
2574 assert(output);
2575 assert(session);
2576
2577 /* Get the datetime for the snapshot output directory. */
2578 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
2579 sizeof(output->datetime));
2580 if (!ret) {
2581 ret = LTTNG_ERR_INVALID;
2582 goto error;
2583 }
2584
2585 /*
2586 * Copy kernel session sockets so we can communicate with the right
2587 * consumer for the snapshot record command.
2588 */
2589 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
2590 if (ret < 0) {
2591 ret = LTTNG_ERR_NOMEM;
2592 goto error;
2593 }
2594
2595 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
2596 if (ret != LTTNG_OK) {
2597 goto error_snapshot;
2598 }
2599
2600 ret = kernel_snapshot_record(ksess, output, wait, nb_streams);
2601 if (ret < 0) {
2602 if (ret == -EINVAL) {
2603 ret = LTTNG_ERR_INVALID;
2604 goto error_snapshot;
2605 }
2606
2607 ret = LTTNG_ERR_SNAPSHOT_FAIL;
2608 goto error_snapshot;
2609 }
2610
2611 ret = LTTNG_OK;
2612
2613 error_snapshot:
2614 /* Clean up copied sockets so this output can use some other later on. */
2615 consumer_destroy_output_sockets(output->consumer);
2616 error:
2617 return ret;
2618 }
2619
2620 /*
2621 * Record a UST snapshot.
2622 *
2623 * Return 0 on success or a LTTNG_ERR error code.
2624 */
2625 static int record_ust_snapshot(struct ltt_ust_session *usess,
2626 struct snapshot_output *output, struct ltt_session *session,
2627 int wait, int nb_streams)
2628 {
2629 int ret;
2630
2631 assert(usess);
2632 assert(output);
2633 assert(session);
2634
2635 /* Get the datetime for the snapshot output directory. */
2636 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
2637 sizeof(output->datetime));
2638 if (!ret) {
2639 ret = LTTNG_ERR_INVALID;
2640 goto error;
2641 }
2642
2643 /*
2644 * Copy UST session sockets so we can communicate with the right
2645 * consumer for the snapshot record command.
2646 */
2647 ret = consumer_copy_sockets(output->consumer, usess->consumer);
2648 if (ret < 0) {
2649 ret = LTTNG_ERR_NOMEM;
2650 goto error;
2651 }
2652
2653 ret = set_relayd_for_snapshot(usess->consumer, output, session);
2654 if (ret != LTTNG_OK) {
2655 goto error_snapshot;
2656 }
2657
2658 ret = ust_app_snapshot_record(usess, output, wait, nb_streams);
2659 if (ret < 0) {
2660 if (ret == -EINVAL) {
2661 ret = LTTNG_ERR_INVALID;
2662 goto error_snapshot;
2663 }
2664
2665 ret = LTTNG_ERR_SNAPSHOT_FAIL;
2666 goto error_snapshot;
2667 }
2668
2669 ret = LTTNG_OK;
2670
2671 error_snapshot:
2672 /* Clean up copied sockets so this output can use some other later on. */
2673 consumer_destroy_output_sockets(output->consumer);
2674 error:
2675 return ret;
2676 }
2677
2678 /*
2679 * Returns the total number of streams for a session or a negative value
2680 * on error.
2681 */
2682 static unsigned int get_total_nb_stream(struct ltt_session *session)
2683 {
2684 unsigned int total_streams = 0;
2685
2686 if (session->kernel_session) {
2687 struct ltt_kernel_session *ksess = session->kernel_session;
2688
2689 total_streams += ksess->stream_count_global;
2690 }
2691
2692 if (session->ust_session) {
2693 struct ltt_ust_session *usess = session->ust_session;
2694
2695 total_streams += ust_app_get_nb_stream(usess);
2696 }
2697
2698 return total_streams;
2699 }
2700
2701 /*
2702 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
2703 *
2704 * The wait parameter is ignored so this call always wait for the snapshot to
2705 * complete before returning.
2706 *
2707 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2708 */
2709 int cmd_snapshot_record(struct ltt_session *session,
2710 struct lttng_snapshot_output *output, int wait)
2711 {
2712 int ret = LTTNG_OK;
2713 unsigned int use_tmp_output = 0;
2714 struct snapshot_output tmp_output;
2715 unsigned int nb_streams, snapshot_success = 0;
2716
2717 assert(session);
2718
2719 DBG("Cmd snapshot record for session %s", session->name);
2720
2721 /*
2722 * Permission denied to create an output if the session is not
2723 * set in no output mode.
2724 */
2725 if (session->output_traces) {
2726 ret = LTTNG_ERR_EPERM;
2727 goto error;
2728 }
2729
2730 /* The session needs to be started at least once. */
2731 if (!session->started) {
2732 ret = LTTNG_ERR_START_SESSION_ONCE;
2733 goto error;
2734 }
2735
2736 /* Use temporary output for the session. */
2737 if (output && *output->ctrl_url != '\0') {
2738 ret = snapshot_output_init(output->max_size, output->name,
2739 output->ctrl_url, output->data_url, session->consumer,
2740 &tmp_output, NULL);
2741 if (ret < 0) {
2742 if (ret == -ENOMEM) {
2743 ret = LTTNG_ERR_NOMEM;
2744 } else {
2745 ret = LTTNG_ERR_INVALID;
2746 }
2747 goto error;
2748 }
2749 /* Use the global session count for the temporary snapshot. */
2750 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
2751 use_tmp_output = 1;
2752 }
2753
2754 /*
2755 * Get the total number of stream of that session which is used by the
2756 * maximum size of the snapshot feature.
2757 */
2758 nb_streams = get_total_nb_stream(session);
2759
2760 if (session->kernel_session) {
2761 struct ltt_kernel_session *ksess = session->kernel_session;
2762
2763 if (use_tmp_output) {
2764 ret = record_kernel_snapshot(ksess, &tmp_output, session,
2765 wait, nb_streams);
2766 if (ret != LTTNG_OK) {
2767 goto error;
2768 }
2769 snapshot_success = 1;
2770 } else {
2771 struct snapshot_output *sout;
2772 struct lttng_ht_iter iter;
2773
2774 rcu_read_lock();
2775 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
2776 &iter.iter, sout, node.node) {
2777 /*
2778 * Make a local copy of the output and assign the possible
2779 * temporary value given by the caller.
2780 */
2781 memset(&tmp_output, 0, sizeof(tmp_output));
2782 memcpy(&tmp_output, sout, sizeof(tmp_output));
2783
2784 /* Use temporary max size. */
2785 if (output->max_size != (uint64_t) -1ULL) {
2786 tmp_output.max_size = output->max_size;
2787 }
2788
2789 /* Use temporary name. */
2790 if (*output->name != '\0') {
2791 strncpy(tmp_output.name, output->name,
2792 sizeof(tmp_output.name));
2793 }
2794
2795 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
2796
2797 ret = record_kernel_snapshot(ksess, &tmp_output,
2798 session, wait, nb_streams);
2799 if (ret != LTTNG_OK) {
2800 rcu_read_unlock();
2801 goto error;
2802 }
2803 snapshot_success = 1;
2804 }
2805 rcu_read_unlock();
2806 }
2807 }
2808
2809 if (session->ust_session) {
2810 struct ltt_ust_session *usess = session->ust_session;
2811
2812 if (use_tmp_output) {
2813 ret = record_ust_snapshot(usess, &tmp_output, session,
2814 wait, nb_streams);
2815 if (ret != LTTNG_OK) {
2816 goto error;
2817 }
2818 snapshot_success = 1;
2819 } else {
2820 struct snapshot_output *sout;
2821 struct lttng_ht_iter iter;
2822
2823 rcu_read_lock();
2824 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
2825 &iter.iter, sout, node.node) {
2826 /*
2827 * Make a local copy of the output and assign the possible
2828 * temporary value given by the caller.
2829 */
2830 memset(&tmp_output, 0, sizeof(tmp_output));
2831 memcpy(&tmp_output, sout, sizeof(tmp_output));
2832
2833 /* Use temporary max size. */
2834 if (output->max_size != (uint64_t) -1ULL) {
2835 tmp_output.max_size = output->max_size;
2836 }
2837
2838 /* Use temporary name. */
2839 if (*output->name != '\0') {
2840 strncpy(tmp_output.name, output->name,
2841 sizeof(tmp_output.name));
2842 }
2843
2844 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
2845
2846 ret = record_ust_snapshot(usess, &tmp_output, session,
2847 wait, nb_streams);
2848 if (ret != LTTNG_OK) {
2849 rcu_read_unlock();
2850 goto error;
2851 }
2852 snapshot_success = 1;
2853 }
2854 rcu_read_unlock();
2855 }
2856 }
2857
2858 if (snapshot_success) {
2859 session->snapshot.nb_snapshot++;
2860 }
2861
2862 error:
2863 return ret;
2864 }
2865
2866 /*
2867 * Init command subsystem.
2868 */
2869 void cmd_init(void)
2870 {
2871 /*
2872 * Set network sequence index to 1 for streams to match a relayd
2873 * socket on the consumer side.
2874 */
2875 pthread_mutex_lock(&relayd_net_seq_idx_lock);
2876 relayd_net_seq_idx = 1;
2877 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
2878
2879 DBG("Command subsystem initialized");
2880 }
LTTng 2.0 tools and control repository
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