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[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-sessiond.h"
34 #include "kernel.h"
35 #include "kernel-consumer.h"
36 #include "lttng-sessiond.h"
37 #include "utils.h"
38 #include "syscall.h"
39
40 #include "cmd.h"
41
42 /*
43 * Used to keep a unique index for each relayd socket created where this value
44 * is associated with streams on the consumer so it can match the right relayd
45 * to send to. It must be accessed with the relayd_net_seq_idx_lock
46 * held.
47 */
48 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
49 static uint64_t relayd_net_seq_idx;
50
51 /*
52 * Both functions below are special case for the Kernel domain when
53 * enabling/disabling all events.
54 */
55 static
56 int enable_kevent_all(struct ltt_session *session,
57 struct lttng_domain *domain, char *channel_name,
58 struct lttng_event *event,
59 char *filter_expression,
60 struct lttng_filter_bytecode *filter, int wpipe);
61 static
62 int disable_kevent_all(struct ltt_session *session, int domain,
63 char *channel_name,
64 struct lttng_event *event);
65
66 /*
67 * Create a session path used by list_lttng_sessions for the case that the
68 * session consumer is on the network.
69 */
70 static int build_network_session_path(char *dst, size_t size,
71 struct ltt_session *session)
72 {
73 int ret, kdata_port, udata_port;
74 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
75 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
76
77 assert(session);
78 assert(dst);
79
80 memset(tmp_urls, 0, sizeof(tmp_urls));
81 memset(tmp_uurl, 0, sizeof(tmp_uurl));
82
83 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
84
85 if (session->kernel_session && session->kernel_session->consumer) {
86 kuri = &session->kernel_session->consumer->dst.net.control;
87 kdata_port = session->kernel_session->consumer->dst.net.data.port;
88 }
89
90 if (session->ust_session && session->ust_session->consumer) {
91 uuri = &session->ust_session->consumer->dst.net.control;
92 udata_port = session->ust_session->consumer->dst.net.data.port;
93 }
94
95 if (uuri == NULL && kuri == NULL) {
96 uri = &session->consumer->dst.net.control;
97 kdata_port = session->consumer->dst.net.data.port;
98 } else if (kuri && uuri) {
99 ret = uri_compare(kuri, uuri);
100 if (ret) {
101 /* Not Equal */
102 uri = kuri;
103 /* Build uuri URL string */
104 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
105 if (ret < 0) {
106 goto error;
107 }
108 } else {
109 uri = kuri;
110 }
111 } else if (kuri && uuri == NULL) {
112 uri = kuri;
113 } else if (uuri && kuri == NULL) {
114 uri = uuri;
115 }
116
117 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
118 if (ret < 0) {
119 goto error;
120 }
121
122 /*
123 * Do we have a UST url set. If yes, this means we have both kernel and UST
124 * to print.
125 */
126 if (*tmp_uurl != '\0') {
127 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
128 tmp_urls, kdata_port, tmp_uurl, udata_port);
129 } else {
130 int dport;
131 if (kuri || (!kuri && !uuri)) {
132 dport = kdata_port;
133 } else {
134 /* No kernel URI, use the UST port. */
135 dport = udata_port;
136 }
137 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
138 }
139
140 error:
141 return ret;
142 }
143
144 /*
145 * Fill lttng_channel array of all channels.
146 */
147 static void list_lttng_channels(int domain, struct ltt_session *session,
148 struct lttng_channel *channels)
149 {
150 int i = 0;
151 struct ltt_kernel_channel *kchan;
152
153 DBG("Listing channels for session %s", session->name);
154
155 switch (domain) {
156 case LTTNG_DOMAIN_KERNEL:
157 /* Kernel channels */
158 if (session->kernel_session != NULL) {
159 cds_list_for_each_entry(kchan,
160 &session->kernel_session->channel_list.head, list) {
161 /* Copy lttng_channel struct to array */
162 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
163 channels[i].enabled = kchan->enabled;
164 i++;
165 }
166 }
167 break;
168 case LTTNG_DOMAIN_UST:
169 {
170 struct lttng_ht_iter iter;
171 struct ltt_ust_channel *uchan;
172
173 rcu_read_lock();
174 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
175 &iter.iter, uchan, node.node) {
176 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
177 channels[i].attr.overwrite = uchan->attr.overwrite;
178 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
179 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
180 channels[i].attr.switch_timer_interval =
181 uchan->attr.switch_timer_interval;
182 channels[i].attr.read_timer_interval =
183 uchan->attr.read_timer_interval;
184 channels[i].enabled = uchan->enabled;
185 channels[i].attr.tracefile_size = uchan->tracefile_size;
186 channels[i].attr.tracefile_count = uchan->tracefile_count;
187 switch (uchan->attr.output) {
188 case LTTNG_UST_MMAP:
189 default:
190 channels[i].attr.output = LTTNG_EVENT_MMAP;
191 break;
192 }
193 i++;
194 }
195 rcu_read_unlock();
196 break;
197 }
198 default:
199 break;
200 }
201 }
202
203 /*
204 * Create a list of agent domain events.
205 *
206 * Return number of events in list on success or else a negative value.
207 */
208 static int list_lttng_agent_events(struct agent *agt,
209 struct lttng_event **events)
210 {
211 int i = 0, ret = 0;
212 unsigned int nb_event = 0;
213 struct agent_event *event;
214 struct lttng_event *tmp_events;
215 struct lttng_ht_iter iter;
216
217 assert(agt);
218 assert(events);
219
220 DBG3("Listing agent events");
221
222 nb_event = lttng_ht_get_count(agt->events);
223 if (nb_event == 0) {
224 ret = nb_event;
225 goto error;
226 }
227
228 tmp_events = zmalloc(nb_event * sizeof(*tmp_events));
229 if (!tmp_events) {
230 PERROR("zmalloc agent events session");
231 ret = -LTTNG_ERR_FATAL;
232 goto error;
233 }
234
235 rcu_read_lock();
236 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
237 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
238 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
239 tmp_events[i].enabled = event->enabled;
240 tmp_events[i].loglevel = event->loglevel;
241 tmp_events[i].loglevel_type = event->loglevel_type;
242 i++;
243 }
244 rcu_read_unlock();
245
246 *events = tmp_events;
247 ret = nb_event;
248
249 error:
250 assert(nb_event == i);
251 return ret;
252 }
253
254 /*
255 * Create a list of ust global domain events.
256 */
257 static int list_lttng_ust_global_events(char *channel_name,
258 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
259 {
260 int i = 0, ret = 0;
261 unsigned int nb_event = 0;
262 struct lttng_ht_iter iter;
263 struct lttng_ht_node_str *node;
264 struct ltt_ust_channel *uchan;
265 struct ltt_ust_event *uevent;
266 struct lttng_event *tmp;
267
268 DBG("Listing UST global events for channel %s", channel_name);
269
270 rcu_read_lock();
271
272 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
273 node = lttng_ht_iter_get_node_str(&iter);
274 if (node == NULL) {
275 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
276 goto error;
277 }
278
279 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
280
281 nb_event += lttng_ht_get_count(uchan->events);
282
283 if (nb_event == 0) {
284 ret = nb_event;
285 goto error;
286 }
287
288 DBG3("Listing UST global %d events", nb_event);
289
290 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
291 if (tmp == NULL) {
292 ret = LTTNG_ERR_FATAL;
293 goto error;
294 }
295
296 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
297 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
298 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
299 tmp[i].enabled = uevent->enabled;
300
301 switch (uevent->attr.instrumentation) {
302 case LTTNG_UST_TRACEPOINT:
303 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
304 break;
305 case LTTNG_UST_PROBE:
306 tmp[i].type = LTTNG_EVENT_PROBE;
307 break;
308 case LTTNG_UST_FUNCTION:
309 tmp[i].type = LTTNG_EVENT_FUNCTION;
310 break;
311 }
312
313 tmp[i].loglevel = uevent->attr.loglevel;
314 switch (uevent->attr.loglevel_type) {
315 case LTTNG_UST_LOGLEVEL_ALL:
316 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
317 break;
318 case LTTNG_UST_LOGLEVEL_RANGE:
319 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
320 break;
321 case LTTNG_UST_LOGLEVEL_SINGLE:
322 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
323 break;
324 }
325 if (uevent->filter) {
326 tmp[i].filter = 1;
327 }
328 if (uevent->exclusion) {
329 tmp[i].exclusion = 1;
330 }
331 i++;
332 }
333
334 ret = nb_event;
335 *events = tmp;
336
337 error:
338 rcu_read_unlock();
339 return ret;
340 }
341
342 /*
343 * Fill lttng_event array of all kernel events in the channel.
344 */
345 static int list_lttng_kernel_events(char *channel_name,
346 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
347 {
348 int i = 0, ret;
349 unsigned int nb_event;
350 struct ltt_kernel_event *event;
351 struct ltt_kernel_channel *kchan;
352
353 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
354 if (kchan == NULL) {
355 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
356 goto error;
357 }
358
359 nb_event = kchan->event_count;
360
361 DBG("Listing events for channel %s", kchan->channel->name);
362
363 if (nb_event == 0) {
364 *events = NULL;
365 goto syscall;
366 }
367
368 *events = zmalloc(nb_event * sizeof(struct lttng_event));
369 if (*events == NULL) {
370 ret = LTTNG_ERR_FATAL;
371 goto error;
372 }
373
374 /* Kernel channels */
375 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
376 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
377 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
378 (*events)[i].enabled = event->enabled;
379
380 switch (event->event->instrumentation) {
381 case LTTNG_KERNEL_TRACEPOINT:
382 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
383 break;
384 case LTTNG_KERNEL_KRETPROBE:
385 (*events)[i].type = LTTNG_EVENT_FUNCTION;
386 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
387 sizeof(struct lttng_kernel_kprobe));
388 break;
389 case LTTNG_KERNEL_KPROBE:
390 (*events)[i].type = LTTNG_EVENT_PROBE;
391 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
392 sizeof(struct lttng_kernel_kprobe));
393 break;
394 case LTTNG_KERNEL_FUNCTION:
395 (*events)[i].type = LTTNG_EVENT_FUNCTION;
396 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
397 sizeof(struct lttng_kernel_function));
398 break;
399 case LTTNG_KERNEL_NOOP:
400 (*events)[i].type = LTTNG_EVENT_NOOP;
401 break;
402 case LTTNG_KERNEL_SYSCALL:
403 (*events)[i].type = LTTNG_EVENT_SYSCALL;
404 break;
405 case LTTNG_KERNEL_ALL:
406 assert(0);
407 break;
408 }
409 i++;
410 }
411
412 syscall:
413 if (syscall_table) {
414 ssize_t new_size;
415
416 new_size = syscall_list_channel(kchan, events, nb_event);
417 if (new_size < 0) {
418 free(events);
419 ret = -new_size;
420 goto error;
421 }
422 nb_event = new_size;
423 }
424
425 return nb_event;
426
427 error:
428 /* Negate the error code to differentiate the size from an error */
429 return -ret;
430 }
431
432 /*
433 * Add URI so the consumer output object. Set the correct path depending on the
434 * domain adding the default trace directory.
435 */
436 static int add_uri_to_consumer(struct consumer_output *consumer,
437 struct lttng_uri *uri, int domain, const char *session_name)
438 {
439 int ret = LTTNG_OK;
440 const char *default_trace_dir;
441
442 assert(uri);
443
444 if (consumer == NULL) {
445 DBG("No consumer detected. Don't add URI. Stopping.");
446 ret = LTTNG_ERR_NO_CONSUMER;
447 goto error;
448 }
449
450 switch (domain) {
451 case LTTNG_DOMAIN_KERNEL:
452 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
453 break;
454 case LTTNG_DOMAIN_UST:
455 default_trace_dir = DEFAULT_UST_TRACE_DIR;
456 break;
457 default:
458 /*
459 * This case is possible is we try to add the URI to the global tracing
460 * session consumer object which in this case there is no subdir.
461 */
462 default_trace_dir = "";
463 }
464
465 switch (uri->dtype) {
466 case LTTNG_DST_IPV4:
467 case LTTNG_DST_IPV6:
468 DBG2("Setting network URI to consumer");
469
470 if (consumer->type == CONSUMER_DST_NET) {
471 if ((uri->stype == LTTNG_STREAM_CONTROL &&
472 consumer->dst.net.control_isset) ||
473 (uri->stype == LTTNG_STREAM_DATA &&
474 consumer->dst.net.data_isset)) {
475 ret = LTTNG_ERR_URL_EXIST;
476 goto error;
477 }
478 } else {
479 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
480 }
481
482 consumer->type = CONSUMER_DST_NET;
483
484 /* Set URI into consumer output object */
485 ret = consumer_set_network_uri(consumer, uri);
486 if (ret < 0) {
487 ret = -ret;
488 goto error;
489 } else if (ret == 1) {
490 /*
491 * URI was the same in the consumer so we do not append the subdir
492 * again so to not duplicate output dir.
493 */
494 ret = LTTNG_OK;
495 goto error;
496 }
497
498 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
499 ret = consumer_set_subdir(consumer, session_name);
500 if (ret < 0) {
501 ret = LTTNG_ERR_FATAL;
502 goto error;
503 }
504 }
505
506 if (uri->stype == LTTNG_STREAM_CONTROL) {
507 /* On a new subdir, reappend the default trace dir. */
508 strncat(consumer->subdir, default_trace_dir,
509 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
510 DBG3("Append domain trace name to subdir %s", consumer->subdir);
511 }
512
513 break;
514 case LTTNG_DST_PATH:
515 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
516 memset(consumer->dst.trace_path, 0,
517 sizeof(consumer->dst.trace_path));
518 strncpy(consumer->dst.trace_path, uri->dst.path,
519 sizeof(consumer->dst.trace_path));
520 /* Append default trace dir */
521 strncat(consumer->dst.trace_path, default_trace_dir,
522 sizeof(consumer->dst.trace_path) -
523 strlen(consumer->dst.trace_path) - 1);
524 /* Flag consumer as local. */
525 consumer->type = CONSUMER_DST_LOCAL;
526 break;
527 }
528
529 ret = LTTNG_OK;
530
531 error:
532 return ret;
533 }
534
535 /*
536 * Init tracing by creating trace directory and sending fds kernel consumer.
537 */
538 static int init_kernel_tracing(struct ltt_kernel_session *session)
539 {
540 int ret = 0;
541 struct lttng_ht_iter iter;
542 struct consumer_socket *socket;
543
544 assert(session);
545
546 rcu_read_lock();
547
548 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
549 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
550 socket, node.node) {
551 pthread_mutex_lock(socket->lock);
552 ret = kernel_consumer_send_session(socket, session);
553 pthread_mutex_unlock(socket->lock);
554 if (ret < 0) {
555 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
556 goto error;
557 }
558 }
559 }
560
561 error:
562 rcu_read_unlock();
563 return ret;
564 }
565
566 /*
567 * Create a socket to the relayd using the URI.
568 *
569 * On success, the relayd_sock pointer is set to the created socket.
570 * Else, it's stays untouched and a lttcomm error code is returned.
571 */
572 static int create_connect_relayd(struct lttng_uri *uri,
573 struct lttcomm_relayd_sock **relayd_sock)
574 {
575 int ret;
576 struct lttcomm_relayd_sock *rsock;
577
578 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
579 RELAYD_VERSION_COMM_MINOR);
580 if (!rsock) {
581 ret = LTTNG_ERR_FATAL;
582 goto error;
583 }
584
585 /*
586 * Connect to relayd so we can proceed with a session creation. This call
587 * can possibly block for an arbitrary amount of time to set the health
588 * state to be in poll execution.
589 */
590 health_poll_entry();
591 ret = relayd_connect(rsock);
592 health_poll_exit();
593 if (ret < 0) {
594 ERR("Unable to reach lttng-relayd");
595 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
596 goto free_sock;
597 }
598
599 /* Create socket for control stream. */
600 if (uri->stype == LTTNG_STREAM_CONTROL) {
601 DBG3("Creating relayd stream socket from URI");
602
603 /* Check relayd version */
604 ret = relayd_version_check(rsock);
605 if (ret < 0) {
606 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
607 goto close_sock;
608 }
609 } else if (uri->stype == LTTNG_STREAM_DATA) {
610 DBG3("Creating relayd data socket from URI");
611 } else {
612 /* Command is not valid */
613 ERR("Relayd invalid stream type: %d", uri->stype);
614 ret = LTTNG_ERR_INVALID;
615 goto close_sock;
616 }
617
618 *relayd_sock = rsock;
619
620 return LTTNG_OK;
621
622 close_sock:
623 /* The returned value is not useful since we are on an error path. */
624 (void) relayd_close(rsock);
625 free_sock:
626 free(rsock);
627 error:
628 return ret;
629 }
630
631 /*
632 * Connect to the relayd using URI and send the socket to the right consumer.
633 */
634 static int send_consumer_relayd_socket(int domain, unsigned int session_id,
635 struct lttng_uri *relayd_uri, struct consumer_output *consumer,
636 struct consumer_socket *consumer_sock,
637 char *session_name, char *hostname, int session_live_timer)
638 {
639 int ret;
640 struct lttcomm_relayd_sock *rsock = NULL;
641
642 /* Connect to relayd and make version check if uri is the control. */
643 ret = create_connect_relayd(relayd_uri, &rsock);
644 if (ret != LTTNG_OK) {
645 goto error;
646 }
647 assert(rsock);
648
649 /* Set the network sequence index if not set. */
650 if (consumer->net_seq_index == (uint64_t) -1ULL) {
651 pthread_mutex_lock(&relayd_net_seq_idx_lock);
652 /*
653 * Increment net_seq_idx because we are about to transfer the
654 * new relayd socket to the consumer.
655 * Assign unique key so the consumer can match streams.
656 */
657 consumer->net_seq_index = ++relayd_net_seq_idx;
658 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
659 }
660
661 /* Send relayd socket to consumer. */
662 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
663 relayd_uri->stype, session_id,
664 session_name, hostname, session_live_timer);
665 if (ret < 0) {
666 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
667 goto close_sock;
668 }
669
670 /* Flag that the corresponding socket was sent. */
671 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
672 consumer_sock->control_sock_sent = 1;
673 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
674 consumer_sock->data_sock_sent = 1;
675 }
676
677 ret = LTTNG_OK;
678
679 /*
680 * Close socket which was dup on the consumer side. The session daemon does
681 * NOT keep track of the relayd socket(s) once transfer to the consumer.
682 */
683
684 close_sock:
685 (void) relayd_close(rsock);
686 free(rsock);
687
688 error:
689 if (ret != LTTNG_OK) {
690 /*
691 * The consumer output for this session should not be used anymore
692 * since the relayd connection failed thus making any tracing or/and
693 * streaming not usable.
694 */
695 consumer->enabled = 0;
696 }
697 return ret;
698 }
699
700 /*
701 * Send both relayd sockets to a specific consumer and domain. This is a
702 * helper function to facilitate sending the information to the consumer for a
703 * session.
704 */
705 static int send_consumer_relayd_sockets(int domain, unsigned int session_id,
706 struct consumer_output *consumer, struct consumer_socket *sock,
707 char *session_name, char *hostname, int session_live_timer)
708 {
709 int ret = LTTNG_OK;
710
711 assert(consumer);
712 assert(sock);
713
714 /* Sending control relayd socket. */
715 if (!sock->control_sock_sent) {
716 ret = send_consumer_relayd_socket(domain, session_id,
717 &consumer->dst.net.control, consumer, sock,
718 session_name, hostname, session_live_timer);
719 if (ret != LTTNG_OK) {
720 goto error;
721 }
722 }
723
724 /* Sending data relayd socket. */
725 if (!sock->data_sock_sent) {
726 ret = send_consumer_relayd_socket(domain, session_id,
727 &consumer->dst.net.data, consumer, sock,
728 session_name, hostname, session_live_timer);
729 if (ret != LTTNG_OK) {
730 goto error;
731 }
732 }
733
734 error:
735 return ret;
736 }
737
738 /*
739 * Setup relayd connections for a tracing session. First creates the socket to
740 * the relayd and send them to the right domain consumer. Consumer type MUST be
741 * network.
742 */
743 int cmd_setup_relayd(struct ltt_session *session)
744 {
745 int ret = LTTNG_OK;
746 struct ltt_ust_session *usess;
747 struct ltt_kernel_session *ksess;
748 struct consumer_socket *socket;
749 struct lttng_ht_iter iter;
750
751 assert(session);
752
753 usess = session->ust_session;
754 ksess = session->kernel_session;
755
756 DBG("Setting relayd for session %s", session->name);
757
758 rcu_read_lock();
759
760 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
761 && usess->consumer->enabled) {
762 /* For each consumer socket, send relayd sockets */
763 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
764 socket, node.node) {
765 pthread_mutex_lock(socket->lock);
766 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
767 usess->consumer, socket,
768 session->name, session->hostname,
769 session->live_timer);
770 pthread_mutex_unlock(socket->lock);
771 if (ret != LTTNG_OK) {
772 goto error;
773 }
774 /* Session is now ready for network streaming. */
775 session->net_handle = 1;
776 }
777 }
778
779 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
780 && ksess->consumer->enabled) {
781 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
782 socket, node.node) {
783 pthread_mutex_lock(socket->lock);
784 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
785 ksess->consumer, socket,
786 session->name, session->hostname,
787 session->live_timer);
788 pthread_mutex_unlock(socket->lock);
789 if (ret != LTTNG_OK) {
790 goto error;
791 }
792 /* Session is now ready for network streaming. */
793 session->net_handle = 1;
794 }
795 }
796
797 error:
798 rcu_read_unlock();
799 return ret;
800 }
801
802 /*
803 * Start a kernel session by opening all necessary streams.
804 */
805 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
806 {
807 int ret;
808 struct ltt_kernel_channel *kchan;
809
810 /* Open kernel metadata */
811 if (ksess->metadata == NULL && ksess->output_traces) {
812 ret = kernel_open_metadata(ksess);
813 if (ret < 0) {
814 ret = LTTNG_ERR_KERN_META_FAIL;
815 goto error;
816 }
817 }
818
819 /* Open kernel metadata stream */
820 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
821 ret = kernel_open_metadata_stream(ksess);
822 if (ret < 0) {
823 ERR("Kernel create metadata stream failed");
824 ret = LTTNG_ERR_KERN_STREAM_FAIL;
825 goto error;
826 }
827 }
828
829 /* For each channel */
830 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
831 if (kchan->stream_count == 0) {
832 ret = kernel_open_channel_stream(kchan);
833 if (ret < 0) {
834 ret = LTTNG_ERR_KERN_STREAM_FAIL;
835 goto error;
836 }
837 /* Update the stream global counter */
838 ksess->stream_count_global += ret;
839 }
840 }
841
842 /* Setup kernel consumer socket and send fds to it */
843 ret = init_kernel_tracing(ksess);
844 if (ret != 0) {
845 ret = LTTNG_ERR_KERN_START_FAIL;
846 goto error;
847 }
848
849 /* This start the kernel tracing */
850 ret = kernel_start_session(ksess);
851 if (ret < 0) {
852 ret = LTTNG_ERR_KERN_START_FAIL;
853 goto error;
854 }
855
856 /* Quiescent wait after starting trace */
857 kernel_wait_quiescent(kernel_tracer_fd);
858
859 ksess->active = 1;
860
861 ret = LTTNG_OK;
862
863 error:
864 return ret;
865 }
866
867 /*
868 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
869 */
870 int cmd_disable_channel(struct ltt_session *session, int domain,
871 char *channel_name)
872 {
873 int ret;
874 struct ltt_ust_session *usess;
875
876 usess = session->ust_session;
877
878 rcu_read_lock();
879
880 switch (domain) {
881 case LTTNG_DOMAIN_KERNEL:
882 {
883 ret = channel_kernel_disable(session->kernel_session,
884 channel_name);
885 if (ret != LTTNG_OK) {
886 goto error;
887 }
888
889 kernel_wait_quiescent(kernel_tracer_fd);
890 break;
891 }
892 case LTTNG_DOMAIN_UST:
893 {
894 struct ltt_ust_channel *uchan;
895 struct lttng_ht *chan_ht;
896
897 chan_ht = usess->domain_global.channels;
898
899 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
900 if (uchan == NULL) {
901 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
902 goto error;
903 }
904
905 ret = channel_ust_disable(usess, uchan);
906 if (ret != LTTNG_OK) {
907 goto error;
908 }
909 break;
910 }
911 #if 0
912 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
913 case LTTNG_DOMAIN_UST_EXEC_NAME:
914 case LTTNG_DOMAIN_UST_PID:
915 #endif
916 default:
917 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
918 goto error;
919 }
920
921 ret = LTTNG_OK;
922
923 error:
924 rcu_read_unlock();
925 return ret;
926 }
927
928 /*
929 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
930 *
931 * The wpipe arguments is used as a notifier for the kernel thread.
932 */
933 int cmd_enable_channel(struct ltt_session *session,
934 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
935 {
936 int ret;
937 struct ltt_ust_session *usess = session->ust_session;
938 struct lttng_ht *chan_ht;
939
940 assert(session);
941 assert(attr);
942 assert(domain);
943
944 DBG("Enabling channel %s for session %s", attr->name, session->name);
945
946 rcu_read_lock();
947
948 /*
949 * Don't try to enable a channel if the session has been started at
950 * some point in time before. The tracer does not allow it.
951 */
952 if (session->has_been_started) {
953 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
954 goto error;
955 }
956
957 /*
958 * If the session is a live session, remove the switch timer, the
959 * live timer does the same thing but sends also synchronisation
960 * beacons for inactive streams.
961 */
962 if (session->live_timer > 0) {
963 attr->attr.live_timer_interval = session->live_timer;
964 attr->attr.switch_timer_interval = 0;
965 }
966
967 /*
968 * The ringbuffer (both in user space and kernel) behave badly in overwrite
969 * mode and with less than 2 subbuf so block it right away and send back an
970 * invalid attribute error.
971 */
972 if (attr->attr.overwrite && attr->attr.num_subbuf < 2) {
973 ret = LTTNG_ERR_INVALID;
974 goto error;
975 }
976
977 switch (domain->type) {
978 case LTTNG_DOMAIN_KERNEL:
979 {
980 struct ltt_kernel_channel *kchan;
981
982 kchan = trace_kernel_get_channel_by_name(attr->name,
983 session->kernel_session);
984 if (kchan == NULL) {
985 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
986 if (attr->name[0] != '\0') {
987 session->kernel_session->has_non_default_channel = 1;
988 }
989 } else {
990 ret = channel_kernel_enable(session->kernel_session, kchan);
991 }
992
993 if (ret != LTTNG_OK) {
994 goto error;
995 }
996
997 kernel_wait_quiescent(kernel_tracer_fd);
998 break;
999 }
1000 case LTTNG_DOMAIN_UST:
1001 {
1002 struct ltt_ust_channel *uchan;
1003
1004 chan_ht = usess->domain_global.channels;
1005
1006 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1007 if (uchan == NULL) {
1008 ret = channel_ust_create(usess, attr, domain->buf_type);
1009 if (attr->name[0] != '\0') {
1010 usess->has_non_default_channel = 1;
1011 }
1012 } else {
1013 ret = channel_ust_enable(usess, uchan);
1014 }
1015 break;
1016 }
1017 default:
1018 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1019 goto error;
1020 }
1021
1022 error:
1023 rcu_read_unlock();
1024 return ret;
1025 }
1026
1027
1028 /*
1029 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1030 */
1031 int cmd_disable_event(struct ltt_session *session, int domain,
1032 char *channel_name,
1033 struct lttng_event *event)
1034 {
1035 int ret;
1036 char *event_name;
1037
1038 DBG("Disable event command for event \'%s\'", event->name);
1039
1040 event_name = event->name;
1041
1042 if (event->loglevel_type || event->loglevel || event->enabled
1043 || event->pid || event->filter || event->exclusion) {
1044 return LTTNG_ERR_UNK;
1045 }
1046 /* Special handling for kernel domain all events. */
1047 if (domain == LTTNG_DOMAIN_KERNEL && !strcmp(event_name, "*")) {
1048 return disable_kevent_all(session, domain, channel_name, event);
1049 }
1050
1051 rcu_read_lock();
1052
1053 switch (domain) {
1054 case LTTNG_DOMAIN_KERNEL:
1055 {
1056 struct ltt_kernel_channel *kchan;
1057 struct ltt_kernel_session *ksess;
1058
1059 ksess = session->kernel_session;
1060
1061 /*
1062 * If a non-default channel has been created in the
1063 * session, explicitely require that -c chan_name needs
1064 * to be provided.
1065 */
1066 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1067 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1068 goto error;
1069 }
1070
1071 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1072 if (kchan == NULL) {
1073 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1074 goto error;
1075 }
1076
1077 switch (event->type) {
1078 case LTTNG_EVENT_ALL:
1079 case LTTNG_EVENT_TRACEPOINT:
1080 ret = event_kernel_disable_tracepoint(kchan, event_name);
1081 if (ret != LTTNG_OK) {
1082 goto error;
1083 }
1084 break;
1085 case LTTNG_EVENT_SYSCALL:
1086 ret = event_kernel_disable_syscall(kchan, event_name);
1087 if (ret != LTTNG_OK) {
1088 goto error;
1089 }
1090 break;
1091 default:
1092 ret = LTTNG_ERR_UNK;
1093 goto error;
1094 }
1095
1096 kernel_wait_quiescent(kernel_tracer_fd);
1097 break;
1098 }
1099 case LTTNG_DOMAIN_UST:
1100 {
1101 struct ltt_ust_channel *uchan;
1102 struct ltt_ust_session *usess;
1103
1104 usess = session->ust_session;
1105
1106 /*
1107 * If a non-default channel has been created in the
1108 * session, explicitely require that -c chan_name needs
1109 * to be provided.
1110 */
1111 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1112 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1113 goto error;
1114 }
1115
1116 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1117 channel_name);
1118 if (uchan == NULL) {
1119 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1120 goto error;
1121 }
1122
1123 switch (event->type) {
1124 case LTTNG_EVENT_ALL:
1125 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
1126 if (ret != LTTNG_OK) {
1127 goto error;
1128 }
1129 break;
1130 default:
1131 ret = LTTNG_ERR_UNK;
1132 goto error;
1133 }
1134
1135 DBG3("Disable UST event %s in channel %s completed", event_name,
1136 channel_name);
1137 break;
1138 }
1139 case LTTNG_DOMAIN_LOG4J:
1140 case LTTNG_DOMAIN_JUL:
1141 {
1142 struct agent *agt;
1143 struct ltt_ust_session *usess = session->ust_session;
1144
1145 assert(usess);
1146
1147 switch (event->type) {
1148 case LTTNG_EVENT_ALL:
1149 break;
1150 default:
1151 ret = LTTNG_ERR_UNK;
1152 goto error;
1153 }
1154
1155 agt = trace_ust_find_agent(usess, domain);
1156 if (!agt) {
1157 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1158 goto error;
1159 }
1160 /* The wild card * means that everything should be disabled. */
1161 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1162 ret = event_agent_disable_all(usess, agt);
1163 } else {
1164 ret = event_agent_disable(usess, agt, event_name);
1165 }
1166 if (ret != LTTNG_OK) {
1167 goto error;
1168 }
1169
1170 break;
1171 }
1172 #if 0
1173 case LTTNG_DOMAIN_UST_EXEC_NAME:
1174 case LTTNG_DOMAIN_UST_PID:
1175 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1176 #endif
1177 default:
1178 ret = LTTNG_ERR_UND;
1179 goto error;
1180 }
1181
1182 ret = LTTNG_OK;
1183
1184 error:
1185 rcu_read_unlock();
1186 return ret;
1187 }
1188
1189 /*
1190 * Command LTTNG_DISABLE_EVENT for event "*" processed by the client thread.
1191 */
1192 static
1193 int disable_kevent_all(struct ltt_session *session, int domain,
1194 char *channel_name,
1195 struct lttng_event *event)
1196 {
1197 int ret;
1198
1199 rcu_read_lock();
1200
1201 switch (domain) {
1202 case LTTNG_DOMAIN_KERNEL:
1203 {
1204 struct ltt_kernel_session *ksess;
1205 struct ltt_kernel_channel *kchan;
1206
1207 ksess = session->kernel_session;
1208
1209 /*
1210 * If a non-default channel has been created in the
1211 * session, explicitely require that -c chan_name needs
1212 * to be provided.
1213 */
1214 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1215 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1216 goto error;
1217 }
1218
1219 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1220 if (kchan == NULL) {
1221 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1222 goto error;
1223 }
1224
1225 switch (event->type) {
1226 case LTTNG_EVENT_ALL:
1227 ret = event_kernel_disable_all(kchan);
1228 if (ret != LTTNG_OK) {
1229 goto error;
1230 }
1231 break;
1232 case LTTNG_EVENT_SYSCALL:
1233 ret = event_kernel_disable_syscall(kchan, "");
1234 if (ret != LTTNG_OK) {
1235 goto error;
1236 }
1237 break;
1238 default:
1239 ret = LTTNG_ERR_UNK;
1240 goto error;
1241 }
1242
1243 kernel_wait_quiescent(kernel_tracer_fd);
1244 break;
1245 }
1246 default:
1247 ret = LTTNG_ERR_UND;
1248 goto error;
1249 }
1250
1251 ret = LTTNG_OK;
1252
1253 error:
1254 rcu_read_unlock();
1255 return ret;
1256 }
1257
1258 /*
1259 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1260 */
1261 int cmd_add_context(struct ltt_session *session, int domain,
1262 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1263 {
1264 int ret, chan_kern_created = 0, chan_ust_created = 0;
1265
1266 switch (domain) {
1267 case LTTNG_DOMAIN_KERNEL:
1268 assert(session->kernel_session);
1269
1270 if (session->kernel_session->channel_count == 0) {
1271 /* Create default channel */
1272 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1273 if (ret != LTTNG_OK) {
1274 goto error;
1275 }
1276 chan_kern_created = 1;
1277 }
1278 /* Add kernel context to kernel tracer */
1279 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1280 if (ret != LTTNG_OK) {
1281 goto error;
1282 }
1283 break;
1284 case LTTNG_DOMAIN_UST:
1285 {
1286 struct ltt_ust_session *usess = session->ust_session;
1287 unsigned int chan_count;
1288
1289 assert(usess);
1290
1291 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1292 if (chan_count == 0) {
1293 struct lttng_channel *attr;
1294 /* Create default channel */
1295 attr = channel_new_default_attr(domain, usess->buffer_type);
1296 if (attr == NULL) {
1297 ret = LTTNG_ERR_FATAL;
1298 goto error;
1299 }
1300
1301 ret = channel_ust_create(usess, attr, usess->buffer_type);
1302 if (ret != LTTNG_OK) {
1303 free(attr);
1304 goto error;
1305 }
1306 free(attr);
1307 chan_ust_created = 1;
1308 }
1309
1310 ret = context_ust_add(usess, domain, ctx, channel_name);
1311 if (ret != LTTNG_OK) {
1312 goto error;
1313 }
1314 break;
1315 }
1316 #if 0
1317 case LTTNG_DOMAIN_UST_EXEC_NAME:
1318 case LTTNG_DOMAIN_UST_PID:
1319 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1320 #endif
1321 default:
1322 ret = LTTNG_ERR_UND;
1323 goto error;
1324 }
1325
1326 return LTTNG_OK;
1327
1328 error:
1329 if (chan_kern_created) {
1330 struct ltt_kernel_channel *kchan =
1331 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1332 session->kernel_session);
1333 /* Created previously, this should NOT fail. */
1334 assert(kchan);
1335 kernel_destroy_channel(kchan);
1336 }
1337
1338 if (chan_ust_created) {
1339 struct ltt_ust_channel *uchan =
1340 trace_ust_find_channel_by_name(
1341 session->ust_session->domain_global.channels,
1342 DEFAULT_CHANNEL_NAME);
1343 /* Created previously, this should NOT fail. */
1344 assert(uchan);
1345 /* Remove from the channel list of the session. */
1346 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1347 uchan);
1348 trace_ust_destroy_channel(uchan);
1349 }
1350 return ret;
1351 }
1352
1353 static int validate_event_name(const char *name)
1354 {
1355 int ret = 0;
1356 const char *c = name;
1357 const char *event_name_end = c + LTTNG_SYMBOL_NAME_LEN;
1358
1359 /*
1360 * Make sure that unescaped wildcards are only used as the last
1361 * character of the event name.
1362 */
1363 while (c < event_name_end) {
1364 switch (*c) {
1365 case '\0':
1366 goto end;
1367 case '\\':
1368 c++;
1369 break;
1370 case '*':
1371 if ((c + 1) < event_name_end && *(c + 1)) {
1372 /* Wildcard is not the last character */
1373 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1374 goto end;
1375 }
1376 default:
1377 break;
1378 }
1379 c++;
1380 }
1381 end:
1382 return ret;
1383 }
1384
1385 /*
1386 * Command LTTNG_ENABLE_EVENT processed by the client thread.
1387 */
1388 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1389 char *channel_name, struct lttng_event *event,
1390 char *filter_expression,
1391 struct lttng_filter_bytecode *filter,
1392 struct lttng_event_exclusion *exclusion,
1393 int wpipe)
1394 {
1395 int ret, channel_created = 0;
1396 struct lttng_channel *attr;
1397
1398 assert(session);
1399 assert(event);
1400 assert(channel_name);
1401
1402 DBG("Enable event command for event \'%s\'", event->name);
1403
1404 /* Special handling for kernel domain all events. */
1405 if (domain->type == LTTNG_DOMAIN_KERNEL && !strcmp(event->name, "*")) {
1406 return enable_kevent_all(session, domain, channel_name, event,
1407 filter_expression, filter, wpipe);
1408 }
1409
1410 ret = validate_event_name(event->name);
1411 if (ret) {
1412 goto error;
1413 }
1414
1415 rcu_read_lock();
1416
1417 switch (domain->type) {
1418 case LTTNG_DOMAIN_KERNEL:
1419 {
1420 struct ltt_kernel_channel *kchan;
1421
1422 /*
1423 * If a non-default channel has been created in the
1424 * session, explicitely require that -c chan_name needs
1425 * to be provided.
1426 */
1427 if (session->kernel_session->has_non_default_channel
1428 && channel_name[0] == '\0') {
1429 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1430 goto error;
1431 }
1432
1433 kchan = trace_kernel_get_channel_by_name(channel_name,
1434 session->kernel_session);
1435 if (kchan == NULL) {
1436 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1437 LTTNG_BUFFER_GLOBAL);
1438 if (attr == NULL) {
1439 ret = LTTNG_ERR_FATAL;
1440 goto error;
1441 }
1442 strncpy(attr->name, channel_name, sizeof(attr->name));
1443
1444 ret = cmd_enable_channel(session, domain, attr, wpipe);
1445 if (ret != LTTNG_OK) {
1446 free(attr);
1447 goto error;
1448 }
1449 free(attr);
1450
1451 channel_created = 1;
1452 }
1453
1454 /* Get the newly created kernel channel pointer */
1455 kchan = trace_kernel_get_channel_by_name(channel_name,
1456 session->kernel_session);
1457 if (kchan == NULL) {
1458 /* This sould not happen... */
1459 ret = LTTNG_ERR_FATAL;
1460 goto error;
1461 }
1462
1463 switch (event->type) {
1464 case LTTNG_EVENT_ALL:
1465 case LTTNG_EVENT_PROBE:
1466 case LTTNG_EVENT_FUNCTION:
1467 case LTTNG_EVENT_FUNCTION_ENTRY:
1468 case LTTNG_EVENT_TRACEPOINT:
1469 ret = event_kernel_enable_tracepoint(kchan, event);
1470 if (ret != LTTNG_OK) {
1471 if (channel_created) {
1472 /* Let's not leak a useless channel. */
1473 kernel_destroy_channel(kchan);
1474 }
1475 goto error;
1476 }
1477 break;
1478 case LTTNG_EVENT_SYSCALL:
1479 ret = event_kernel_enable_syscall(kchan, event->name);
1480 if (ret != LTTNG_OK) {
1481 goto error;
1482 }
1483 break;
1484 default:
1485 ret = LTTNG_ERR_UNK;
1486 goto error;
1487 }
1488
1489 kernel_wait_quiescent(kernel_tracer_fd);
1490 break;
1491 }
1492 case LTTNG_DOMAIN_UST:
1493 {
1494 struct ltt_ust_channel *uchan;
1495 struct ltt_ust_session *usess = session->ust_session;
1496
1497 assert(usess);
1498
1499 /*
1500 * If a non-default channel has been created in the
1501 * session, explicitely require that -c chan_name needs
1502 * to be provided.
1503 */
1504 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1505 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1506 goto error;
1507 }
1508
1509 /* Get channel from global UST domain */
1510 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1511 channel_name);
1512 if (uchan == NULL) {
1513 /* Create default channel */
1514 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1515 usess->buffer_type);
1516 if (attr == NULL) {
1517 ret = LTTNG_ERR_FATAL;
1518 goto error;
1519 }
1520 strncpy(attr->name, channel_name, sizeof(attr->name));
1521
1522 ret = cmd_enable_channel(session, domain, attr, wpipe);
1523 if (ret != LTTNG_OK) {
1524 free(attr);
1525 goto error;
1526 }
1527 free(attr);
1528
1529 /* Get the newly created channel reference back */
1530 uchan = trace_ust_find_channel_by_name(
1531 usess->domain_global.channels, channel_name);
1532 assert(uchan);
1533 }
1534
1535 /* At this point, the session and channel exist on the tracer */
1536 ret = event_ust_enable_tracepoint(usess, uchan, event,
1537 filter_expression, filter, exclusion);
1538 if (ret != LTTNG_OK) {
1539 goto error;
1540 }
1541 break;
1542 }
1543 case LTTNG_DOMAIN_LOG4J:
1544 case LTTNG_DOMAIN_JUL:
1545 {
1546 const char *default_event_name, *default_chan_name;
1547 struct agent *agt;
1548 struct lttng_event uevent;
1549 struct lttng_domain tmp_dom;
1550 struct ltt_ust_session *usess = session->ust_session;
1551
1552 assert(usess);
1553
1554 agt = trace_ust_find_agent(usess, domain->type);
1555 if (!agt) {
1556 agt = agent_create(domain->type);
1557 if (!agt) {
1558 ret = -LTTNG_ERR_NOMEM;
1559 goto error;
1560 }
1561 agent_add(agt, usess->agents);
1562 }
1563
1564 /* Create the default tracepoint. */
1565 memset(&uevent, 0, sizeof(uevent));
1566 uevent.type = LTTNG_EVENT_TRACEPOINT;
1567 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
1568 default_event_name = event_get_default_agent_ust_name(domain->type);
1569 if (!default_event_name) {
1570 ret = -LTTNG_ERR_FATAL;
1571 goto error;
1572 }
1573 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
1574 uevent.name[sizeof(uevent.name) - 1] = '\0';
1575
1576 /*
1577 * The domain type is changed because we are about to enable the
1578 * default channel and event for the JUL domain that are hardcoded.
1579 * This happens in the UST domain.
1580 */
1581 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
1582 tmp_dom.type = LTTNG_DOMAIN_UST;
1583
1584 if (domain->type == LTTNG_DOMAIN_LOG4J) {
1585 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
1586 } else {
1587 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
1588 }
1589
1590 ret = cmd_enable_event(session, &tmp_dom, (char *) default_chan_name,
1591 &uevent, filter_expression, filter, NULL, wpipe);
1592 if (ret != LTTNG_OK && ret != LTTNG_ERR_UST_EVENT_ENABLED) {
1593 goto error;
1594 }
1595
1596 /* The wild card * means that everything should be enabled. */
1597 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1598 ret = event_agent_enable_all(usess, agt, event, filter);
1599 } else {
1600 ret = event_agent_enable(usess, agt, event, filter);
1601 }
1602 if (ret != LTTNG_OK) {
1603 goto error;
1604 }
1605
1606 break;
1607 }
1608 #if 0
1609 case LTTNG_DOMAIN_UST_EXEC_NAME:
1610 case LTTNG_DOMAIN_UST_PID:
1611 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1612 #endif
1613 default:
1614 ret = LTTNG_ERR_UND;
1615 goto error;
1616 }
1617
1618 ret = LTTNG_OK;
1619
1620 error:
1621 rcu_read_unlock();
1622 return ret;
1623 }
1624
1625 /*
1626 * Command LTTNG_ENABLE_EVENT for event "*" processed by the client thread.
1627 */
1628 static
1629 int enable_kevent_all(struct ltt_session *session,
1630 struct lttng_domain *domain, char *channel_name,
1631 struct lttng_event *event,
1632 char *filter_expression,
1633 struct lttng_filter_bytecode *filter, int wpipe)
1634 {
1635 int ret;
1636 struct lttng_channel *attr;
1637
1638 assert(session);
1639 assert(channel_name);
1640
1641 rcu_read_lock();
1642
1643 switch (domain->type) {
1644 case LTTNG_DOMAIN_KERNEL:
1645 {
1646 struct ltt_kernel_channel *kchan;
1647
1648 assert(session->kernel_session);
1649
1650 /*
1651 * If a non-default channel has been created in the
1652 * session, explicitely require that -c chan_name needs
1653 * to be provided.
1654 */
1655 if (session->kernel_session->has_non_default_channel
1656 && channel_name[0] == '\0') {
1657 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1658 goto error;
1659 }
1660
1661 kchan = trace_kernel_get_channel_by_name(channel_name,
1662 session->kernel_session);
1663 if (kchan == NULL) {
1664 /* Create default channel */
1665 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1666 LTTNG_BUFFER_GLOBAL);
1667 if (attr == NULL) {
1668 ret = LTTNG_ERR_FATAL;
1669 goto error;
1670 }
1671 strncpy(attr->name, channel_name, sizeof(attr->name));
1672
1673 ret = cmd_enable_channel(session, domain, attr, wpipe);
1674 if (ret != LTTNG_OK) {
1675 free(attr);
1676 goto error;
1677 }
1678 free(attr);
1679
1680 /* Get the newly created kernel channel pointer */
1681 kchan = trace_kernel_get_channel_by_name(channel_name,
1682 session->kernel_session);
1683 assert(kchan);
1684 }
1685
1686 switch (event->type) {
1687 case LTTNG_EVENT_SYSCALL:
1688 ret = event_kernel_enable_syscall(kchan, "");
1689 if (ret != LTTNG_OK) {
1690 goto error;
1691 }
1692 break;
1693 case LTTNG_EVENT_TRACEPOINT:
1694 /*
1695 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
1696 * events already registered to the channel.
1697 */
1698 ret = event_kernel_enable_all_tracepoints(kchan, kernel_tracer_fd);
1699 break;
1700 case LTTNG_EVENT_ALL:
1701 /* Enable syscalls and tracepoints */
1702 ret = event_kernel_enable_all(kchan, kernel_tracer_fd);
1703 break;
1704 default:
1705 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1706 goto error;
1707 }
1708
1709 /* Manage return value */
1710 if (ret != LTTNG_OK) {
1711 /*
1712 * On error, cmd_enable_channel call will take care of destroying
1713 * the created channel if it was needed.
1714 */
1715 goto error;
1716 }
1717
1718 kernel_wait_quiescent(kernel_tracer_fd);
1719 break;
1720 }
1721 default:
1722 ret = LTTNG_ERR_UND;
1723 goto error;
1724 }
1725
1726 ret = LTTNG_OK;
1727
1728 error:
1729 rcu_read_unlock();
1730 return ret;
1731 }
1732
1733
1734 /*
1735 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1736 */
1737 ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
1738 {
1739 int ret;
1740 ssize_t nb_events = 0;
1741
1742 switch (domain) {
1743 case LTTNG_DOMAIN_KERNEL:
1744 nb_events = kernel_list_events(kernel_tracer_fd, events);
1745 if (nb_events < 0) {
1746 ret = LTTNG_ERR_KERN_LIST_FAIL;
1747 goto error;
1748 }
1749 break;
1750 case LTTNG_DOMAIN_UST:
1751 nb_events = ust_app_list_events(events);
1752 if (nb_events < 0) {
1753 ret = LTTNG_ERR_UST_LIST_FAIL;
1754 goto error;
1755 }
1756 break;
1757 case LTTNG_DOMAIN_LOG4J:
1758 case LTTNG_DOMAIN_JUL:
1759 nb_events = agent_list_events(events, domain);
1760 if (nb_events < 0) {
1761 ret = LTTNG_ERR_UST_LIST_FAIL;
1762 goto error;
1763 }
1764 break;
1765 default:
1766 ret = LTTNG_ERR_UND;
1767 goto error;
1768 }
1769
1770 return nb_events;
1771
1772 error:
1773 /* Return negative value to differentiate return code */
1774 return -ret;
1775 }
1776
1777 /*
1778 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1779 */
1780 ssize_t cmd_list_tracepoint_fields(int domain,
1781 struct lttng_event_field **fields)
1782 {
1783 int ret;
1784 ssize_t nb_fields = 0;
1785
1786 switch (domain) {
1787 case LTTNG_DOMAIN_UST:
1788 nb_fields = ust_app_list_event_fields(fields);
1789 if (nb_fields < 0) {
1790 ret = LTTNG_ERR_UST_LIST_FAIL;
1791 goto error;
1792 }
1793 break;
1794 case LTTNG_DOMAIN_KERNEL:
1795 default: /* fall-through */
1796 ret = LTTNG_ERR_UND;
1797 goto error;
1798 }
1799
1800 return nb_fields;
1801
1802 error:
1803 /* Return negative value to differentiate return code */
1804 return -ret;
1805 }
1806
1807 ssize_t cmd_list_syscalls(struct lttng_event **events)
1808 {
1809 return syscall_table_list(events);
1810 }
1811
1812 /*
1813 * Command LTTNG_START_TRACE processed by the client thread.
1814 */
1815 int cmd_start_trace(struct ltt_session *session)
1816 {
1817 int ret;
1818 unsigned long nb_chan = 0;
1819 struct ltt_kernel_session *ksession;
1820 struct ltt_ust_session *usess;
1821
1822 assert(session);
1823
1824 /* Ease our life a bit ;) */
1825 ksession = session->kernel_session;
1826 usess = session->ust_session;
1827
1828 /* Is the session already started? */
1829 if (session->active) {
1830 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1831 goto error;
1832 }
1833
1834 /*
1835 * Starting a session without channel is useless since after that it's not
1836 * possible to enable channel thus inform the client.
1837 */
1838 if (usess && usess->domain_global.channels) {
1839 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
1840 }
1841 if (ksession) {
1842 nb_chan += ksession->channel_count;
1843 }
1844 if (!nb_chan) {
1845 ret = LTTNG_ERR_NO_CHANNEL;
1846 goto error;
1847 }
1848
1849 /* Kernel tracing */
1850 if (ksession != NULL) {
1851 ret = start_kernel_session(ksession, kernel_tracer_fd);
1852 if (ret != LTTNG_OK) {
1853 goto error;
1854 }
1855 }
1856
1857 /* Flag session that trace should start automatically */
1858 if (usess) {
1859 /*
1860 * Even though the start trace might fail, flag this session active so
1861 * other application coming in are started by default.
1862 */
1863 usess->active = 1;
1864
1865 ret = ust_app_start_trace_all(usess);
1866 if (ret < 0) {
1867 ret = LTTNG_ERR_UST_START_FAIL;
1868 goto error;
1869 }
1870 }
1871
1872 /* Flag this after a successful start. */
1873 session->has_been_started = 1;
1874 session->active = 1;
1875
1876 ret = LTTNG_OK;
1877
1878 error:
1879 return ret;
1880 }
1881
1882 /*
1883 * Command LTTNG_STOP_TRACE processed by the client thread.
1884 */
1885 int cmd_stop_trace(struct ltt_session *session)
1886 {
1887 int ret;
1888 struct ltt_kernel_channel *kchan;
1889 struct ltt_kernel_session *ksession;
1890 struct ltt_ust_session *usess;
1891
1892 assert(session);
1893
1894 /* Short cut */
1895 ksession = session->kernel_session;
1896 usess = session->ust_session;
1897
1898 /* Session is not active. Skip everythong and inform the client. */
1899 if (!session->active) {
1900 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
1901 goto error;
1902 }
1903
1904 /* Kernel tracer */
1905 if (ksession && ksession->active) {
1906 DBG("Stop kernel tracing");
1907
1908 /* Flush metadata if exist */
1909 if (ksession->metadata_stream_fd >= 0) {
1910 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
1911 if (ret < 0) {
1912 ERR("Kernel metadata flush failed");
1913 }
1914 }
1915
1916 /* Flush all buffers before stopping */
1917 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
1918 ret = kernel_flush_buffer(kchan);
1919 if (ret < 0) {
1920 ERR("Kernel flush buffer error");
1921 }
1922 }
1923
1924 ret = kernel_stop_session(ksession);
1925 if (ret < 0) {
1926 ret = LTTNG_ERR_KERN_STOP_FAIL;
1927 goto error;
1928 }
1929
1930 kernel_wait_quiescent(kernel_tracer_fd);
1931
1932 ksession->active = 0;
1933 }
1934
1935 if (usess && usess->active) {
1936 /*
1937 * Even though the stop trace might fail, flag this session inactive so
1938 * other application coming in are not started by default.
1939 */
1940 usess->active = 0;
1941
1942 ret = ust_app_stop_trace_all(usess);
1943 if (ret < 0) {
1944 ret = LTTNG_ERR_UST_STOP_FAIL;
1945 goto error;
1946 }
1947 }
1948
1949 /* Flag inactive after a successful stop. */
1950 session->active = 0;
1951 ret = LTTNG_OK;
1952
1953 error:
1954 return ret;
1955 }
1956
1957 /*
1958 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
1959 */
1960 int cmd_set_consumer_uri(int domain, struct ltt_session *session,
1961 size_t nb_uri, struct lttng_uri *uris)
1962 {
1963 int ret, i;
1964 struct ltt_kernel_session *ksess = session->kernel_session;
1965 struct ltt_ust_session *usess = session->ust_session;
1966 struct consumer_output *consumer = NULL;
1967
1968 assert(session);
1969 assert(uris);
1970 assert(nb_uri > 0);
1971
1972 /* Can't set consumer URI if the session is active. */
1973 if (session->active) {
1974 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1975 goto error;
1976 }
1977
1978 /*
1979 * This case switch makes sure the domain session has a temporary consumer
1980 * so the URL can be set.
1981 */
1982 switch (domain) {
1983 case 0:
1984 /* Code flow error. A session MUST always have a consumer object */
1985 assert(session->consumer);
1986 /*
1987 * The URL will be added to the tracing session consumer instead of a
1988 * specific domain consumer.
1989 */
1990 consumer = session->consumer;
1991 break;
1992 case LTTNG_DOMAIN_KERNEL:
1993 /* Code flow error if we don't have a kernel session here. */
1994 assert(ksess);
1995 assert(ksess->consumer);
1996 consumer = ksess->consumer;
1997 break;
1998 case LTTNG_DOMAIN_UST:
1999 /* Code flow error if we don't have a kernel session here. */
2000 assert(usess);
2001 assert(usess->consumer);
2002 consumer = usess->consumer;
2003 break;
2004 }
2005
2006 for (i = 0; i < nb_uri; i++) {
2007 ret = add_uri_to_consumer(consumer, &uris[i], domain, session->name);
2008 if (ret != LTTNG_OK) {
2009 goto error;
2010 }
2011 }
2012
2013 /*
2014 * Make sure to set the session in output mode after we set URI since a
2015 * session can be created without URL (thus flagged in no output mode).
2016 */
2017 session->output_traces = 1;
2018 if (ksess) {
2019 ksess->output_traces = 1;
2020 } else if (usess) {
2021 usess->output_traces = 1;
2022 }
2023
2024 /* All good! */
2025 ret = LTTNG_OK;
2026
2027 error:
2028 return ret;
2029 }
2030
2031 /*
2032 * Command LTTNG_CREATE_SESSION processed by the client thread.
2033 */
2034 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
2035 size_t nb_uri, lttng_sock_cred *creds, unsigned int live_timer)
2036 {
2037 int ret;
2038 struct ltt_session *session;
2039
2040 assert(name);
2041 assert(creds);
2042
2043 /*
2044 * Verify if the session already exist
2045 *
2046 * XXX: There is no need for the session lock list here since the caller
2047 * (process_client_msg) is holding it. We might want to change that so a
2048 * single command does not lock the entire session list.
2049 */
2050 session = session_find_by_name(name);
2051 if (session != NULL) {
2052 ret = LTTNG_ERR_EXIST_SESS;
2053 goto find_error;
2054 }
2055
2056 /* Create tracing session in the registry */
2057 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
2058 LTTNG_SOCK_GET_GID_CRED(creds));
2059 if (ret != LTTNG_OK) {
2060 goto session_error;
2061 }
2062
2063 /*
2064 * Get the newly created session pointer back
2065 *
2066 * XXX: There is no need for the session lock list here since the caller
2067 * (process_client_msg) is holding it. We might want to change that so a
2068 * single command does not lock the entire session list.
2069 */
2070 session = session_find_by_name(name);
2071 assert(session);
2072
2073 session->live_timer = live_timer;
2074 /* Create default consumer output for the session not yet created. */
2075 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
2076 if (session->consumer == NULL) {
2077 ret = LTTNG_ERR_FATAL;
2078 goto consumer_error;
2079 }
2080
2081 if (uris) {
2082 ret = cmd_set_consumer_uri(0, session, nb_uri, uris);
2083 if (ret != LTTNG_OK) {
2084 goto consumer_error;
2085 }
2086 session->output_traces = 1;
2087 } else {
2088 session->output_traces = 0;
2089 DBG2("Session %s created with no output", session->name);
2090 }
2091
2092 session->consumer->enabled = 1;
2093
2094 return LTTNG_OK;
2095
2096 consumer_error:
2097 session_destroy(session);
2098 session_error:
2099 find_error:
2100 return ret;
2101 }
2102
2103 /*
2104 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
2105 */
2106 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
2107 size_t nb_uri, lttng_sock_cred *creds)
2108 {
2109 int ret;
2110 struct ltt_session *session;
2111 struct snapshot_output *new_output = NULL;
2112
2113 assert(name);
2114 assert(creds);
2115
2116 /*
2117 * Create session in no output mode with URIs set to NULL. The uris we've
2118 * received are for a default snapshot output if one.
2119 */
2120 ret = cmd_create_session_uri(name, NULL, 0, creds, -1);
2121 if (ret != LTTNG_OK) {
2122 goto error;
2123 }
2124
2125 /* Get the newly created session pointer back. This should NEVER fail. */
2126 session = session_find_by_name(name);
2127 assert(session);
2128
2129 /* Flag session for snapshot mode. */
2130 session->snapshot_mode = 1;
2131
2132 /* Skip snapshot output creation if no URI is given. */
2133 if (nb_uri == 0) {
2134 goto end;
2135 }
2136
2137 new_output = snapshot_output_alloc();
2138 if (!new_output) {
2139 ret = LTTNG_ERR_NOMEM;
2140 goto error_snapshot_alloc;
2141 }
2142
2143 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
2144 uris, nb_uri, session->consumer, new_output, &session->snapshot);
2145 if (ret < 0) {
2146 if (ret == -ENOMEM) {
2147 ret = LTTNG_ERR_NOMEM;
2148 } else {
2149 ret = LTTNG_ERR_INVALID;
2150 }
2151 goto error_snapshot;
2152 }
2153
2154 rcu_read_lock();
2155 snapshot_add_output(&session->snapshot, new_output);
2156 rcu_read_unlock();
2157
2158 end:
2159 return LTTNG_OK;
2160
2161 error_snapshot:
2162 snapshot_output_destroy(new_output);
2163 error_snapshot_alloc:
2164 session_destroy(session);
2165 error:
2166 return ret;
2167 }
2168
2169 /*
2170 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2171 */
2172 int cmd_destroy_session(struct ltt_session *session, int wpipe)
2173 {
2174 int ret;
2175 struct ltt_ust_session *usess;
2176 struct ltt_kernel_session *ksess;
2177
2178 /* Safety net */
2179 assert(session);
2180
2181 usess = session->ust_session;
2182 ksess = session->kernel_session;
2183
2184 /* Clean kernel session teardown */
2185 kernel_destroy_session(ksess);
2186
2187 /* UST session teardown */
2188 if (usess) {
2189 /* Close any relayd session */
2190 consumer_output_send_destroy_relayd(usess->consumer);
2191
2192 /* Destroy every UST application related to this session. */
2193 ret = ust_app_destroy_trace_all(usess);
2194 if (ret) {
2195 ERR("Error in ust_app_destroy_trace_all");
2196 }
2197
2198 /* Clean up the rest. */
2199 trace_ust_destroy_session(usess);
2200 }
2201
2202 /*
2203 * Must notify the kernel thread here to update it's poll set in order to
2204 * remove the channel(s)' fd just destroyed.
2205 */
2206 ret = notify_thread_pipe(wpipe);
2207 if (ret < 0) {
2208 PERROR("write kernel poll pipe");
2209 }
2210
2211 ret = session_destroy(session);
2212
2213 return ret;
2214 }
2215
2216 /*
2217 * Command LTTNG_CALIBRATE processed by the client thread.
2218 */
2219 int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2220 {
2221 int ret;
2222
2223 switch (domain) {
2224 case LTTNG_DOMAIN_KERNEL:
2225 {
2226 struct lttng_kernel_calibrate kcalibrate;
2227
2228 switch (calibrate->type) {
2229 case LTTNG_CALIBRATE_FUNCTION:
2230 default:
2231 /* Default and only possible calibrate option. */
2232 kcalibrate.type = LTTNG_KERNEL_CALIBRATE_KRETPROBE;
2233 break;
2234 }
2235
2236 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2237 if (ret < 0) {
2238 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
2239 goto error;
2240 }
2241 break;
2242 }
2243 case LTTNG_DOMAIN_UST:
2244 {
2245 struct lttng_ust_calibrate ucalibrate;
2246
2247 switch (calibrate->type) {
2248 case LTTNG_CALIBRATE_FUNCTION:
2249 default:
2250 /* Default and only possible calibrate option. */
2251 ucalibrate.type = LTTNG_UST_CALIBRATE_TRACEPOINT;
2252 break;
2253 }
2254
2255 ret = ust_app_calibrate_glb(&ucalibrate);
2256 if (ret < 0) {
2257 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
2258 goto error;
2259 }
2260 break;
2261 }
2262 default:
2263 ret = LTTNG_ERR_UND;
2264 goto error;
2265 }
2266
2267 ret = LTTNG_OK;
2268
2269 error:
2270 return ret;
2271 }
2272
2273 /*
2274 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2275 */
2276 int cmd_register_consumer(struct ltt_session *session, int domain,
2277 const char *sock_path, struct consumer_data *cdata)
2278 {
2279 int ret, sock;
2280 struct consumer_socket *socket = NULL;
2281
2282 assert(session);
2283 assert(cdata);
2284 assert(sock_path);
2285
2286 switch (domain) {
2287 case LTTNG_DOMAIN_KERNEL:
2288 {
2289 struct ltt_kernel_session *ksess = session->kernel_session;
2290
2291 assert(ksess);
2292
2293 /* Can't register a consumer if there is already one */
2294 if (ksess->consumer_fds_sent != 0) {
2295 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2296 goto error;
2297 }
2298
2299 sock = lttcomm_connect_unix_sock(sock_path);
2300 if (sock < 0) {
2301 ret = LTTNG_ERR_CONNECT_FAIL;
2302 goto error;
2303 }
2304 cdata->cmd_sock = sock;
2305
2306 socket = consumer_allocate_socket(&cdata->cmd_sock);
2307 if (socket == NULL) {
2308 ret = close(sock);
2309 if (ret < 0) {
2310 PERROR("close register consumer");
2311 }
2312 cdata->cmd_sock = -1;
2313 ret = LTTNG_ERR_FATAL;
2314 goto error;
2315 }
2316
2317 socket->lock = zmalloc(sizeof(pthread_mutex_t));
2318 if (socket->lock == NULL) {
2319 PERROR("zmalloc pthread mutex");
2320 ret = LTTNG_ERR_FATAL;
2321 goto error;
2322 }
2323 pthread_mutex_init(socket->lock, NULL);
2324 socket->registered = 1;
2325
2326 rcu_read_lock();
2327 consumer_add_socket(socket, ksess->consumer);
2328 rcu_read_unlock();
2329
2330 pthread_mutex_lock(&cdata->pid_mutex);
2331 cdata->pid = -1;
2332 pthread_mutex_unlock(&cdata->pid_mutex);
2333
2334 break;
2335 }
2336 default:
2337 /* TODO: Userspace tracing */
2338 ret = LTTNG_ERR_UND;
2339 goto error;
2340 }
2341
2342 return LTTNG_OK;
2343
2344 error:
2345 if (socket) {
2346 consumer_destroy_socket(socket);
2347 }
2348 return ret;
2349 }
2350
2351 /*
2352 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2353 */
2354 ssize_t cmd_list_domains(struct ltt_session *session,
2355 struct lttng_domain **domains)
2356 {
2357 int ret, index = 0;
2358 ssize_t nb_dom = 0;
2359 struct agent *agt;
2360 struct lttng_ht_iter iter;
2361
2362 if (session->kernel_session != NULL) {
2363 DBG3("Listing domains found kernel domain");
2364 nb_dom++;
2365 }
2366
2367 if (session->ust_session != NULL) {
2368 DBG3("Listing domains found UST global domain");
2369 nb_dom++;
2370
2371 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2372 agt, node.node) {
2373 if (agt->being_used) {
2374 nb_dom++;
2375 }
2376 }
2377 }
2378
2379 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2380 if (*domains == NULL) {
2381 ret = LTTNG_ERR_FATAL;
2382 goto error;
2383 }
2384
2385 if (session->kernel_session != NULL) {
2386 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2387 index++;
2388 }
2389
2390 if (session->ust_session != NULL) {
2391 (*domains)[index].type = LTTNG_DOMAIN_UST;
2392 (*domains)[index].buf_type = session->ust_session->buffer_type;
2393 index++;
2394
2395 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2396 agt, node.node) {
2397 if (agt->being_used) {
2398 (*domains)[index].type = agt->domain;
2399 (*domains)[index].buf_type = session->ust_session->buffer_type;
2400 index++;
2401 }
2402 }
2403 }
2404
2405 return nb_dom;
2406
2407 error:
2408 /* Return negative value to differentiate return code */
2409 return -ret;
2410 }
2411
2412
2413 /*
2414 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2415 */
2416 ssize_t cmd_list_channels(int domain, struct ltt_session *session,
2417 struct lttng_channel **channels)
2418 {
2419 int ret;
2420 ssize_t nb_chan = 0;
2421
2422 switch (domain) {
2423 case LTTNG_DOMAIN_KERNEL:
2424 if (session->kernel_session != NULL) {
2425 nb_chan = session->kernel_session->channel_count;
2426 }
2427 DBG3("Number of kernel channels %zd", nb_chan);
2428 if (nb_chan <= 0) {
2429 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
2430 }
2431 break;
2432 case LTTNG_DOMAIN_UST:
2433 if (session->ust_session != NULL) {
2434 nb_chan = lttng_ht_get_count(
2435 session->ust_session->domain_global.channels);
2436 }
2437 DBG3("Number of UST global channels %zd", nb_chan);
2438 if (nb_chan <= 0) {
2439 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2440 }
2441 break;
2442 default:
2443 *channels = NULL;
2444 ret = LTTNG_ERR_UND;
2445 goto error;
2446 }
2447
2448 if (nb_chan > 0) {
2449 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
2450 if (*channels == NULL) {
2451 ret = LTTNG_ERR_FATAL;
2452 goto error;
2453 }
2454
2455 list_lttng_channels(domain, session, *channels);
2456 } else {
2457 *channels = NULL;
2458 /* Ret value was set in the domain switch case */
2459 goto error;
2460 }
2461
2462 return nb_chan;
2463
2464 error:
2465 /* Return negative value to differentiate return code */
2466 return -ret;
2467 }
2468
2469 /*
2470 * Command LTTNG_LIST_EVENTS processed by the client thread.
2471 */
2472 ssize_t cmd_list_events(int domain, struct ltt_session *session,
2473 char *channel_name, struct lttng_event **events)
2474 {
2475 int ret = 0;
2476 ssize_t nb_event = 0;
2477
2478 switch (domain) {
2479 case LTTNG_DOMAIN_KERNEL:
2480 if (session->kernel_session != NULL) {
2481 nb_event = list_lttng_kernel_events(channel_name,
2482 session->kernel_session, events);
2483 }
2484 break;
2485 case LTTNG_DOMAIN_UST:
2486 {
2487 if (session->ust_session != NULL) {
2488 nb_event = list_lttng_ust_global_events(channel_name,
2489 &session->ust_session->domain_global, events);
2490 }
2491 break;
2492 }
2493 case LTTNG_DOMAIN_LOG4J:
2494 case LTTNG_DOMAIN_JUL:
2495 if (session->ust_session) {
2496 struct lttng_ht_iter iter;
2497 struct agent *agt;
2498
2499 cds_lfht_for_each_entry(session->ust_session->agents->ht,
2500 &iter.iter, agt, node.node) {
2501 nb_event = list_lttng_agent_events(agt, events);
2502 }
2503 }
2504 break;
2505 default:
2506 ret = LTTNG_ERR_UND;
2507 goto error;
2508 }
2509
2510 return nb_event;
2511
2512 error:
2513 /* Return negative value to differentiate return code */
2514 return -ret;
2515 }
2516
2517 /*
2518 * Using the session list, filled a lttng_session array to send back to the
2519 * client for session listing.
2520 *
2521 * The session list lock MUST be acquired before calling this function. Use
2522 * session_lock_list() and session_unlock_list().
2523 */
2524 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2525 gid_t gid)
2526 {
2527 int ret;
2528 unsigned int i = 0;
2529 struct ltt_session *session;
2530 struct ltt_session_list *list = session_get_list();
2531
2532 DBG("Getting all available session for UID %d GID %d",
2533 uid, gid);
2534 /*
2535 * Iterate over session list and append data after the control struct in
2536 * the buffer.
2537 */
2538 cds_list_for_each_entry(session, &list->head, list) {
2539 /*
2540 * Only list the sessions the user can control.
2541 */
2542 if (!session_access_ok(session, uid, gid)) {
2543 continue;
2544 }
2545
2546 struct ltt_kernel_session *ksess = session->kernel_session;
2547 struct ltt_ust_session *usess = session->ust_session;
2548
2549 if (session->consumer->type == CONSUMER_DST_NET ||
2550 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2551 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2552 ret = build_network_session_path(sessions[i].path,
2553 sizeof(sessions[i].path), session);
2554 } else {
2555 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
2556 session->consumer->dst.trace_path);
2557 }
2558 if (ret < 0) {
2559 PERROR("snprintf session path");
2560 continue;
2561 }
2562
2563 strncpy(sessions[i].name, session->name, NAME_MAX);
2564 sessions[i].name[NAME_MAX - 1] = '\0';
2565 sessions[i].enabled = session->active;
2566 sessions[i].snapshot_mode = session->snapshot_mode;
2567 sessions[i].live_timer_interval = session->live_timer;
2568 i++;
2569 }
2570 }
2571
2572 /*
2573 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2574 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
2575 */
2576 int cmd_data_pending(struct ltt_session *session)
2577 {
2578 int ret;
2579 struct ltt_kernel_session *ksess = session->kernel_session;
2580 struct ltt_ust_session *usess = session->ust_session;
2581
2582 assert(session);
2583
2584 /* Session MUST be stopped to ask for data availability. */
2585 if (session->active) {
2586 ret = LTTNG_ERR_SESSION_STARTED;
2587 goto error;
2588 } else {
2589 /*
2590 * If stopped, just make sure we've started before else the above call
2591 * will always send that there is data pending.
2592 *
2593 * The consumer assumes that when the data pending command is received,
2594 * the trace has been started before or else no output data is written
2595 * by the streams which is a condition for data pending. So, this is
2596 * *VERY* important that we don't ask the consumer before a start
2597 * trace.
2598 */
2599 if (!session->has_been_started) {
2600 ret = 0;
2601 goto error;
2602 }
2603 }
2604
2605 if (ksess && ksess->consumer) {
2606 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2607 if (ret == 1) {
2608 /* Data is still being extracted for the kernel. */
2609 goto error;
2610 }
2611 }
2612
2613 if (usess && usess->consumer) {
2614 ret = consumer_is_data_pending(usess->id, usess->consumer);
2615 if (ret == 1) {
2616 /* Data is still being extracted for the kernel. */
2617 goto error;
2618 }
2619 }
2620
2621 /* Data is ready to be read by a viewer */
2622 ret = 0;
2623
2624 error:
2625 return ret;
2626 }
2627
2628 /*
2629 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
2630 *
2631 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2632 */
2633 int cmd_snapshot_add_output(struct ltt_session *session,
2634 struct lttng_snapshot_output *output, uint32_t *id)
2635 {
2636 int ret;
2637 struct snapshot_output *new_output;
2638
2639 assert(session);
2640 assert(output);
2641
2642 DBG("Cmd snapshot add output for session %s", session->name);
2643
2644 /*
2645 * Permission denied to create an output if the session is not
2646 * set in no output mode.
2647 */
2648 if (session->output_traces) {
2649 ret = LTTNG_ERR_EPERM;
2650 goto error;
2651 }
2652
2653 /* Only one output is allowed until we have the "tee" feature. */
2654 if (session->snapshot.nb_output == 1) {
2655 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
2656 goto error;
2657 }
2658
2659 new_output = snapshot_output_alloc();
2660 if (!new_output) {
2661 ret = LTTNG_ERR_NOMEM;
2662 goto error;
2663 }
2664
2665 ret = snapshot_output_init(output->max_size, output->name,
2666 output->ctrl_url, output->data_url, session->consumer, new_output,
2667 &session->snapshot);
2668 if (ret < 0) {
2669 if (ret == -ENOMEM) {
2670 ret = LTTNG_ERR_NOMEM;
2671 } else {
2672 ret = LTTNG_ERR_INVALID;
2673 }
2674 goto free_error;
2675 }
2676
2677 rcu_read_lock();
2678 snapshot_add_output(&session->snapshot, new_output);
2679 if (id) {
2680 *id = new_output->id;
2681 }
2682 rcu_read_unlock();
2683
2684 return LTTNG_OK;
2685
2686 free_error:
2687 snapshot_output_destroy(new_output);
2688 error:
2689 return ret;
2690 }
2691
2692 /*
2693 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
2694 *
2695 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2696 */
2697 int cmd_snapshot_del_output(struct ltt_session *session,
2698 struct lttng_snapshot_output *output)
2699 {
2700 int ret;
2701 struct snapshot_output *sout = NULL;
2702
2703 assert(session);
2704 assert(output);
2705
2706 rcu_read_lock();
2707
2708 /*
2709 * Permission denied to create an output if the session is not
2710 * set in no output mode.
2711 */
2712 if (session->output_traces) {
2713 ret = LTTNG_ERR_EPERM;
2714 goto error;
2715 }
2716
2717 if (output->id) {
2718 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
2719 session->name);
2720 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
2721 } else if (*output->name != '\0') {
2722 DBG("Cmd snapshot del output name %s for session %s", output->name,
2723 session->name);
2724 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
2725 }
2726 if (!sout) {
2727 ret = LTTNG_ERR_INVALID;
2728 goto error;
2729 }
2730
2731 snapshot_delete_output(&session->snapshot, sout);
2732 snapshot_output_destroy(sout);
2733 ret = LTTNG_OK;
2734
2735 error:
2736 rcu_read_unlock();
2737 return ret;
2738 }
2739
2740 /*
2741 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
2742 *
2743 * If no output is available, outputs is untouched and 0 is returned.
2744 *
2745 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
2746 */
2747 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
2748 struct lttng_snapshot_output **outputs)
2749 {
2750 int ret, idx = 0;
2751 struct lttng_snapshot_output *list;
2752 struct lttng_ht_iter iter;
2753 struct snapshot_output *output;
2754
2755 assert(session);
2756 assert(outputs);
2757
2758 DBG("Cmd snapshot list outputs for session %s", session->name);
2759
2760 /*
2761 * Permission denied to create an output if the session is not
2762 * set in no output mode.
2763 */
2764 if (session->output_traces) {
2765 ret = LTTNG_ERR_EPERM;
2766 goto error;
2767 }
2768
2769 if (session->snapshot.nb_output == 0) {
2770 ret = 0;
2771 goto error;
2772 }
2773
2774 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
2775 if (!list) {
2776 ret = LTTNG_ERR_NOMEM;
2777 goto error;
2778 }
2779
2780 /* Copy list from session to the new list object. */
2781 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
2782 output, node.node) {
2783 assert(output->consumer);
2784 list[idx].id = output->id;
2785 list[idx].max_size = output->max_size;
2786 strncpy(list[idx].name, output->name, sizeof(list[idx].name));
2787 if (output->consumer->type == CONSUMER_DST_LOCAL) {
2788 strncpy(list[idx].ctrl_url, output->consumer->dst.trace_path,
2789 sizeof(list[idx].ctrl_url));
2790 } else {
2791 /* Control URI. */
2792 ret = uri_to_str_url(&output->consumer->dst.net.control,
2793 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
2794 if (ret < 0) {
2795 ret = LTTNG_ERR_NOMEM;
2796 goto free_error;
2797 }
2798
2799 /* Data URI. */
2800 ret = uri_to_str_url(&output->consumer->dst.net.data,
2801 list[idx].data_url, sizeof(list[idx].data_url));
2802 if (ret < 0) {
2803 ret = LTTNG_ERR_NOMEM;
2804 goto free_error;
2805 }
2806 }
2807 idx++;
2808 }
2809
2810 *outputs = list;
2811 return session->snapshot.nb_output;
2812
2813 free_error:
2814 free(list);
2815 error:
2816 return -ret;
2817 }
2818
2819 /*
2820 * Send relayd sockets from snapshot output to consumer. Ignore request if the
2821 * snapshot output is *not* set with a remote destination.
2822 *
2823 * Return 0 on success or a LTTNG_ERR code.
2824 */
2825 static int set_relayd_for_snapshot(struct consumer_output *consumer,
2826 struct snapshot_output *snap_output, struct ltt_session *session)
2827 {
2828 int ret = LTTNG_OK;
2829 struct lttng_ht_iter iter;
2830 struct consumer_socket *socket;
2831
2832 assert(consumer);
2833 assert(snap_output);
2834 assert(session);
2835
2836 DBG2("Set relayd object from snapshot output");
2837
2838 /* Ignore if snapshot consumer output is not network. */
2839 if (snap_output->consumer->type != CONSUMER_DST_NET) {
2840 goto error;
2841 }
2842
2843 /*
2844 * For each consumer socket, create and send the relayd object of the
2845 * snapshot output.
2846 */
2847 rcu_read_lock();
2848 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
2849 socket, node.node) {
2850 ret = send_consumer_relayd_sockets(0, session->id,
2851 snap_output->consumer, socket,
2852 session->name, session->hostname,
2853 session->live_timer);
2854 if (ret != LTTNG_OK) {
2855 rcu_read_unlock();
2856 goto error;
2857 }
2858 }
2859 rcu_read_unlock();
2860
2861 error:
2862 return ret;
2863 }
2864
2865 /*
2866 * Record a kernel snapshot.
2867 *
2868 * Return LTTNG_OK on success or a LTTNG_ERR code.
2869 */
2870 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
2871 struct snapshot_output *output, struct ltt_session *session,
2872 int wait, uint64_t max_stream_size)
2873 {
2874 int ret;
2875
2876 assert(ksess);
2877 assert(output);
2878 assert(session);
2879
2880 /* Get the datetime for the snapshot output directory. */
2881 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
2882 sizeof(output->datetime));
2883 if (!ret) {
2884 ret = LTTNG_ERR_INVALID;
2885 goto error;
2886 }
2887
2888 /*
2889 * Copy kernel session sockets so we can communicate with the right
2890 * consumer for the snapshot record command.
2891 */
2892 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
2893 if (ret < 0) {
2894 ret = LTTNG_ERR_NOMEM;
2895 goto error;
2896 }
2897
2898 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
2899 if (ret != LTTNG_OK) {
2900 goto error_snapshot;
2901 }
2902
2903 ret = kernel_snapshot_record(ksess, output, wait, max_stream_size);
2904 if (ret != LTTNG_OK) {
2905 goto error_snapshot;
2906 }
2907
2908 ret = LTTNG_OK;
2909
2910 error_snapshot:
2911 /* Clean up copied sockets so this output can use some other later on. */
2912 consumer_destroy_output_sockets(output->consumer);
2913 error:
2914 return ret;
2915 }
2916
2917 /*
2918 * Record a UST snapshot.
2919 *
2920 * Return 0 on success or a LTTNG_ERR error code.
2921 */
2922 static int record_ust_snapshot(struct ltt_ust_session *usess,
2923 struct snapshot_output *output, struct ltt_session *session,
2924 int wait, uint64_t max_stream_size)
2925 {
2926 int ret;
2927
2928 assert(usess);
2929 assert(output);
2930 assert(session);
2931
2932 /* Get the datetime for the snapshot output directory. */
2933 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
2934 sizeof(output->datetime));
2935 if (!ret) {
2936 ret = LTTNG_ERR_INVALID;
2937 goto error;
2938 }
2939
2940 /*
2941 * Copy UST session sockets so we can communicate with the right
2942 * consumer for the snapshot record command.
2943 */
2944 ret = consumer_copy_sockets(output->consumer, usess->consumer);
2945 if (ret < 0) {
2946 ret = LTTNG_ERR_NOMEM;
2947 goto error;
2948 }
2949
2950 ret = set_relayd_for_snapshot(usess->consumer, output, session);
2951 if (ret != LTTNG_OK) {
2952 goto error_snapshot;
2953 }
2954
2955 ret = ust_app_snapshot_record(usess, output, wait, max_stream_size);
2956 if (ret < 0) {
2957 switch (-ret) {
2958 case EINVAL:
2959 ret = LTTNG_ERR_INVALID;
2960 break;
2961 case ENODATA:
2962 ret = LTTNG_ERR_SNAPSHOT_NODATA;
2963 break;
2964 default:
2965 ret = LTTNG_ERR_SNAPSHOT_FAIL;
2966 break;
2967 }
2968 goto error_snapshot;
2969 }
2970
2971 ret = LTTNG_OK;
2972
2973 error_snapshot:
2974 /* Clean up copied sockets so this output can use some other later on. */
2975 consumer_destroy_output_sockets(output->consumer);
2976 error:
2977 return ret;
2978 }
2979
2980 /*
2981 * Return the biggest subbuffer size of all channels in the given session.
2982 */
2983 static uint64_t get_session_max_subbuf_size(struct ltt_session *session)
2984 {
2985 uint64_t max_size = 0;
2986
2987 assert(session);
2988
2989 if (session->kernel_session) {
2990 struct ltt_kernel_channel *chan;
2991 struct ltt_kernel_session *ksess = session->kernel_session;
2992
2993 /*
2994 * For each channel, add to the max size the size of each subbuffer
2995 * multiplied by their sized.
2996 */
2997 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
2998 if (chan->channel->attr.subbuf_size > max_size) {
2999 max_size = chan->channel->attr.subbuf_size;
3000 }
3001 }
3002 }
3003
3004 if (session->ust_session) {
3005 struct lttng_ht_iter iter;
3006 struct ltt_ust_channel *uchan;
3007 struct ltt_ust_session *usess = session->ust_session;
3008
3009 cds_lfht_for_each_entry(usess->domain_global.channels->ht, &iter.iter,
3010 uchan, node.node) {
3011 if (uchan->attr.subbuf_size > max_size) {
3012 max_size = uchan->attr.subbuf_size;
3013 }
3014 }
3015 }
3016
3017 return max_size;
3018 }
3019
3020 /*
3021 * Returns the total number of streams for a session or a negative value
3022 * on error.
3023 */
3024 static unsigned int get_session_nb_streams(struct ltt_session *session)
3025 {
3026 unsigned int total_streams = 0;
3027
3028 if (session->kernel_session) {
3029 struct ltt_kernel_session *ksess = session->kernel_session;
3030
3031 total_streams += ksess->stream_count_global;
3032 }
3033
3034 if (session->ust_session) {
3035 struct ltt_ust_session *usess = session->ust_session;
3036
3037 total_streams += ust_app_get_nb_stream(usess);
3038 }
3039
3040 return total_streams;
3041 }
3042
3043 /*
3044 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
3045 *
3046 * The wait parameter is ignored so this call always wait for the snapshot to
3047 * complete before returning.
3048 *
3049 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3050 */
3051 int cmd_snapshot_record(struct ltt_session *session,
3052 struct lttng_snapshot_output *output, int wait)
3053 {
3054 int ret = LTTNG_OK;
3055 unsigned int use_tmp_output = 0;
3056 struct snapshot_output tmp_output;
3057 unsigned int nb_streams, snapshot_success = 0;
3058 uint64_t session_max_size = 0, max_stream_size = 0;
3059
3060 assert(session);
3061 assert(output);
3062
3063 DBG("Cmd snapshot record for session %s", session->name);
3064
3065 /*
3066 * Permission denied to create an output if the session is not
3067 * set in no output mode.
3068 */
3069 if (session->output_traces) {
3070 ret = LTTNG_ERR_EPERM;
3071 goto error;
3072 }
3073
3074 /* The session needs to be started at least once. */
3075 if (!session->has_been_started) {
3076 ret = LTTNG_ERR_START_SESSION_ONCE;
3077 goto error;
3078 }
3079
3080 /* Use temporary output for the session. */
3081 if (*output->ctrl_url != '\0') {
3082 ret = snapshot_output_init(output->max_size, output->name,
3083 output->ctrl_url, output->data_url, session->consumer,
3084 &tmp_output, NULL);
3085 if (ret < 0) {
3086 if (ret == -ENOMEM) {
3087 ret = LTTNG_ERR_NOMEM;
3088 } else {
3089 ret = LTTNG_ERR_INVALID;
3090 }
3091 goto error;
3092 }
3093 /* Use the global session count for the temporary snapshot. */
3094 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3095 use_tmp_output = 1;
3096 }
3097
3098 /*
3099 * Get the session maximum size for a snapshot meaning it will compute the
3100 * size of all streams from all domain.
3101 */
3102 max_stream_size = get_session_max_subbuf_size(session);
3103
3104 nb_streams = get_session_nb_streams(session);
3105 if (nb_streams) {
3106 /*
3107 * The maximum size of the snapshot is the number of streams multiplied
3108 * by the biggest subbuf size of all channels in a session which is the
3109 * maximum stream size available for each stream. The session max size
3110 * is now checked against the snapshot max size value given by the user
3111 * and if lower, an error is returned.
3112 */
3113 session_max_size = max_stream_size * nb_streams;
3114 }
3115
3116 DBG3("Snapshot max size is %" PRIu64 " for max stream size of %" PRIu64,
3117 session_max_size, max_stream_size);
3118
3119 /*
3120 * If we use a temporary output, check right away if the max size fits else
3121 * for each output the max size will be checked.
3122 */
3123 if (use_tmp_output &&
3124 (tmp_output.max_size != 0 &&
3125 tmp_output.max_size < session_max_size)) {
3126 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3127 goto error;
3128 }
3129
3130 if (session->kernel_session) {
3131 struct ltt_kernel_session *ksess = session->kernel_session;
3132
3133 if (use_tmp_output) {
3134 ret = record_kernel_snapshot(ksess, &tmp_output, session,
3135 wait, max_stream_size);
3136 if (ret != LTTNG_OK) {
3137 goto error;
3138 }
3139 snapshot_success = 1;
3140 } else {
3141 struct snapshot_output *sout;
3142 struct lttng_ht_iter iter;
3143
3144 rcu_read_lock();
3145 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3146 &iter.iter, sout, node.node) {
3147 /*
3148 * Make a local copy of the output and assign the possible
3149 * temporary value given by the caller.
3150 */
3151 memset(&tmp_output, 0, sizeof(tmp_output));
3152 memcpy(&tmp_output, sout, sizeof(tmp_output));
3153
3154 /* Use temporary max size. */
3155 if (output->max_size != (uint64_t) -1ULL) {
3156 tmp_output.max_size = output->max_size;
3157 }
3158
3159 if (tmp_output.max_size != 0 &&
3160 tmp_output.max_size < session_max_size) {
3161 rcu_read_unlock();
3162 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3163 goto error;
3164 }
3165
3166 /* Use temporary name. */
3167 if (*output->name != '\0') {
3168 strncpy(tmp_output.name, output->name,
3169 sizeof(tmp_output.name));
3170 }
3171
3172 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3173
3174 ret = record_kernel_snapshot(ksess, &tmp_output,
3175 session, wait, max_stream_size);
3176 if (ret != LTTNG_OK) {
3177 rcu_read_unlock();
3178 goto error;
3179 }
3180 snapshot_success = 1;
3181 }
3182 rcu_read_unlock();
3183 }
3184 }
3185
3186 if (session->ust_session) {
3187 struct ltt_ust_session *usess = session->ust_session;
3188
3189 if (use_tmp_output) {
3190 ret = record_ust_snapshot(usess, &tmp_output, session,
3191 wait, max_stream_size);
3192 if (ret != LTTNG_OK) {
3193 goto error;
3194 }
3195 snapshot_success = 1;
3196 } else {
3197 struct snapshot_output *sout;
3198 struct lttng_ht_iter iter;
3199
3200 rcu_read_lock();
3201 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3202 &iter.iter, sout, node.node) {
3203 /*
3204 * Make a local copy of the output and assign the possible
3205 * temporary value given by the caller.
3206 */
3207 memset(&tmp_output, 0, sizeof(tmp_output));
3208 memcpy(&tmp_output, sout, sizeof(tmp_output));
3209
3210 /* Use temporary max size. */
3211 if (output->max_size != (uint64_t) -1ULL) {
3212 tmp_output.max_size = output->max_size;
3213 }
3214
3215 if (tmp_output.max_size != 0 &&
3216 tmp_output.max_size < session_max_size) {
3217 rcu_read_unlock();
3218 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3219 goto error;
3220 }
3221
3222 /* Use temporary name. */
3223 if (*output->name != '\0') {
3224 strncpy(tmp_output.name, output->name,
3225 sizeof(tmp_output.name));
3226 }
3227
3228 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3229
3230 ret = record_ust_snapshot(usess, &tmp_output, session,
3231 wait, max_stream_size);
3232 if (ret != LTTNG_OK) {
3233 rcu_read_unlock();
3234 goto error;
3235 }
3236 snapshot_success = 1;
3237 }
3238 rcu_read_unlock();
3239 }
3240 }
3241
3242 if (snapshot_success) {
3243 session->snapshot.nb_snapshot++;
3244 } else {
3245 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3246 }
3247
3248 error:
3249 return ret;
3250 }
3251
3252 /*
3253 * Init command subsystem.
3254 */
3255 void cmd_init(void)
3256 {
3257 /*
3258 * Set network sequence index to 1 for streams to match a relayd
3259 * socket on the consumer side.
3260 */
3261 pthread_mutex_lock(&relayd_net_seq_idx_lock);
3262 relayd_net_seq_idx = 1;
3263 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
3264
3265 DBG("Command subsystem initialized");
3266 }
LTTng 2.0 tools and control repository
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