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Prevent the addition of UST events to agent channels
[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 #define _LGPL_SOURCE
20 #include <assert.h>
21 #include <string.h>
22 #include <inttypes.h>
23 #include <urcu/list.h>
24 #include <urcu/uatomic.h>
25
26 #include <common/defaults.h>
27 #include <common/common.h>
28 #include <common/sessiond-comm/sessiond-comm.h>
29 #include <common/relayd/relayd.h>
30 #include <common/utils.h>
31
32 #include "channel.h"
33 #include "consumer.h"
34 #include "event.h"
35 #include "health-sessiond.h"
36 #include "kernel.h"
37 #include "kernel-consumer.h"
38 #include "lttng-sessiond.h"
39 #include "utils.h"
40 #include "syscall.h"
41
42 #include "cmd.h"
43
44 /*
45 * Used to keep a unique index for each relayd socket created where this value
46 * is associated with streams on the consumer so it can match the right relayd
47 * to send to. It must be accessed with the relayd_net_seq_idx_lock
48 * held.
49 */
50 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
51 static uint64_t relayd_net_seq_idx;
52
53 static int validate_event_name(const char *);
54 static int validate_ust_event_name(const char *);
55 static int cmd_enable_event_internal(struct ltt_session *session,
56 struct lttng_domain *domain,
57 char *channel_name, struct lttng_event *event,
58 char *filter_expression,
59 struct lttng_filter_bytecode *filter,
60 struct lttng_event_exclusion *exclusion,
61 int wpipe);
62
63 /*
64 * Create a session path used by list_lttng_sessions for the case that the
65 * session consumer is on the network.
66 */
67 static int build_network_session_path(char *dst, size_t size,
68 struct ltt_session *session)
69 {
70 int ret, kdata_port, udata_port;
71 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
72 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
73
74 assert(session);
75 assert(dst);
76
77 memset(tmp_urls, 0, sizeof(tmp_urls));
78 memset(tmp_uurl, 0, sizeof(tmp_uurl));
79
80 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
81
82 if (session->kernel_session && session->kernel_session->consumer) {
83 kuri = &session->kernel_session->consumer->dst.net.control;
84 kdata_port = session->kernel_session->consumer->dst.net.data.port;
85 }
86
87 if (session->ust_session && session->ust_session->consumer) {
88 uuri = &session->ust_session->consumer->dst.net.control;
89 udata_port = session->ust_session->consumer->dst.net.data.port;
90 }
91
92 if (uuri == NULL && kuri == NULL) {
93 uri = &session->consumer->dst.net.control;
94 kdata_port = session->consumer->dst.net.data.port;
95 } else if (kuri && uuri) {
96 ret = uri_compare(kuri, uuri);
97 if (ret) {
98 /* Not Equal */
99 uri = kuri;
100 /* Build uuri URL string */
101 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
102 if (ret < 0) {
103 goto error;
104 }
105 } else {
106 uri = kuri;
107 }
108 } else if (kuri && uuri == NULL) {
109 uri = kuri;
110 } else if (uuri && kuri == NULL) {
111 uri = uuri;
112 }
113
114 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
115 if (ret < 0) {
116 goto error;
117 }
118
119 /*
120 * Do we have a UST url set. If yes, this means we have both kernel and UST
121 * to print.
122 */
123 if (*tmp_uurl != '\0') {
124 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
125 tmp_urls, kdata_port, tmp_uurl, udata_port);
126 } else {
127 int dport;
128 if (kuri || (!kuri && !uuri)) {
129 dport = kdata_port;
130 } else {
131 /* No kernel URI, use the UST port. */
132 dport = udata_port;
133 }
134 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
135 }
136
137 error:
138 return ret;
139 }
140
141 /*
142 * Fill lttng_channel array of all channels.
143 */
144 static void list_lttng_channels(int domain, struct ltt_session *session,
145 struct lttng_channel *channels)
146 {
147 int i = 0;
148 struct ltt_kernel_channel *kchan;
149
150 DBG("Listing channels for session %s", session->name);
151
152 switch (domain) {
153 case LTTNG_DOMAIN_KERNEL:
154 /* Kernel channels */
155 if (session->kernel_session != NULL) {
156 cds_list_for_each_entry(kchan,
157 &session->kernel_session->channel_list.head, list) {
158 /* Copy lttng_channel struct to array */
159 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
160 channels[i].enabled = kchan->enabled;
161 i++;
162 }
163 }
164 break;
165 case LTTNG_DOMAIN_UST:
166 {
167 struct lttng_ht_iter iter;
168 struct ltt_ust_channel *uchan;
169
170 rcu_read_lock();
171 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
172 &iter.iter, uchan, node.node) {
173 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
174 channels[i].attr.overwrite = uchan->attr.overwrite;
175 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
176 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
177 channels[i].attr.switch_timer_interval =
178 uchan->attr.switch_timer_interval;
179 channels[i].attr.read_timer_interval =
180 uchan->attr.read_timer_interval;
181 channels[i].enabled = uchan->enabled;
182 channels[i].attr.tracefile_size = uchan->tracefile_size;
183 channels[i].attr.tracefile_count = uchan->tracefile_count;
184 switch (uchan->attr.output) {
185 case LTTNG_UST_MMAP:
186 default:
187 channels[i].attr.output = LTTNG_EVENT_MMAP;
188 break;
189 }
190 i++;
191 }
192 rcu_read_unlock();
193 break;
194 }
195 default:
196 break;
197 }
198 }
199
200 /*
201 * Create a list of agent domain events.
202 *
203 * Return number of events in list on success or else a negative value.
204 */
205 static int list_lttng_agent_events(struct agent *agt,
206 struct lttng_event **events)
207 {
208 int i = 0, ret = 0;
209 unsigned int nb_event = 0;
210 struct agent_event *event;
211 struct lttng_event *tmp_events;
212 struct lttng_ht_iter iter;
213
214 assert(agt);
215 assert(events);
216
217 DBG3("Listing agent events");
218
219 rcu_read_lock();
220 nb_event = lttng_ht_get_count(agt->events);
221 rcu_read_unlock();
222 if (nb_event == 0) {
223 ret = nb_event;
224 goto error;
225 }
226
227 tmp_events = zmalloc(nb_event * sizeof(*tmp_events));
228 if (!tmp_events) {
229 PERROR("zmalloc agent events session");
230 ret = -LTTNG_ERR_FATAL;
231 goto error;
232 }
233
234 rcu_read_lock();
235 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
236 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
237 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
238 tmp_events[i].enabled = event->enabled;
239 tmp_events[i].loglevel = event->loglevel;
240 tmp_events[i].loglevel_type = event->loglevel_type;
241 i++;
242 }
243 rcu_read_unlock();
244
245 *events = tmp_events;
246 ret = nb_event;
247
248 error:
249 assert(nb_event == i);
250 return ret;
251 }
252
253 /*
254 * Create a list of ust global domain events.
255 */
256 static int list_lttng_ust_global_events(char *channel_name,
257 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
258 {
259 int i = 0, ret = 0;
260 unsigned int nb_event = 0;
261 struct lttng_ht_iter iter;
262 struct lttng_ht_node_str *node;
263 struct ltt_ust_channel *uchan;
264 struct ltt_ust_event *uevent;
265 struct lttng_event *tmp;
266
267 DBG("Listing UST global events for channel %s", channel_name);
268
269 rcu_read_lock();
270
271 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
272 node = lttng_ht_iter_get_node_str(&iter);
273 if (node == NULL) {
274 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
275 goto error;
276 }
277
278 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
279
280 nb_event = lttng_ht_get_count(uchan->events);
281 if (nb_event == 0) {
282 ret = nb_event;
283 goto error;
284 }
285
286 DBG3("Listing UST global %d events", nb_event);
287
288 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
289 if (tmp == NULL) {
290 ret = LTTNG_ERR_FATAL;
291 goto error;
292 }
293
294 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
295 if (uevent->internal) {
296 /* This event should remain hidden from clients */
297 nb_event--;
298 continue;
299 }
300 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
301 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
302 tmp[i].enabled = uevent->enabled;
303
304 switch (uevent->attr.instrumentation) {
305 case LTTNG_UST_TRACEPOINT:
306 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
307 break;
308 case LTTNG_UST_PROBE:
309 tmp[i].type = LTTNG_EVENT_PROBE;
310 break;
311 case LTTNG_UST_FUNCTION:
312 tmp[i].type = LTTNG_EVENT_FUNCTION;
313 break;
314 }
315
316 tmp[i].loglevel = uevent->attr.loglevel;
317 switch (uevent->attr.loglevel_type) {
318 case LTTNG_UST_LOGLEVEL_ALL:
319 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
320 break;
321 case LTTNG_UST_LOGLEVEL_RANGE:
322 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
323 break;
324 case LTTNG_UST_LOGLEVEL_SINGLE:
325 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
326 break;
327 }
328 if (uevent->filter) {
329 tmp[i].filter = 1;
330 }
331 if (uevent->exclusion) {
332 tmp[i].exclusion = 1;
333 }
334 i++;
335 }
336
337 ret = nb_event;
338 *events = tmp;
339
340 error:
341 rcu_read_unlock();
342 return ret;
343 }
344
345 /*
346 * Fill lttng_event array of all kernel events in the channel.
347 */
348 static int list_lttng_kernel_events(char *channel_name,
349 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
350 {
351 int i = 0, ret;
352 unsigned int nb_event;
353 struct ltt_kernel_event *event;
354 struct ltt_kernel_channel *kchan;
355
356 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
357 if (kchan == NULL) {
358 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
359 goto error;
360 }
361
362 nb_event = kchan->event_count;
363
364 DBG("Listing events for channel %s", kchan->channel->name);
365
366 if (nb_event == 0) {
367 *events = NULL;
368 goto syscall;
369 }
370
371 *events = zmalloc(nb_event * sizeof(struct lttng_event));
372 if (*events == NULL) {
373 ret = LTTNG_ERR_FATAL;
374 goto error;
375 }
376
377 /* Kernel channels */
378 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
379 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
380 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
381 (*events)[i].enabled = event->enabled;
382 (*events)[i].filter =
383 (unsigned char) !!event->filter_expression;
384
385 switch (event->event->instrumentation) {
386 case LTTNG_KERNEL_TRACEPOINT:
387 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
388 break;
389 case LTTNG_KERNEL_KRETPROBE:
390 (*events)[i].type = LTTNG_EVENT_FUNCTION;
391 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
392 sizeof(struct lttng_kernel_kprobe));
393 break;
394 case LTTNG_KERNEL_KPROBE:
395 (*events)[i].type = LTTNG_EVENT_PROBE;
396 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
397 sizeof(struct lttng_kernel_kprobe));
398 break;
399 case LTTNG_KERNEL_FUNCTION:
400 (*events)[i].type = LTTNG_EVENT_FUNCTION;
401 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
402 sizeof(struct lttng_kernel_function));
403 break;
404 case LTTNG_KERNEL_NOOP:
405 (*events)[i].type = LTTNG_EVENT_NOOP;
406 break;
407 case LTTNG_KERNEL_SYSCALL:
408 (*events)[i].type = LTTNG_EVENT_SYSCALL;
409 break;
410 case LTTNG_KERNEL_ALL:
411 assert(0);
412 break;
413 }
414 i++;
415 }
416
417 syscall:
418 if (syscall_table) {
419 ssize_t new_size;
420
421 new_size = syscall_list_channel(kchan, events, nb_event);
422 if (new_size < 0) {
423 free(events);
424 ret = -new_size;
425 goto error;
426 }
427 nb_event = new_size;
428 }
429
430 return nb_event;
431
432 error:
433 /* Negate the error code to differentiate the size from an error */
434 return -ret;
435 }
436
437 /*
438 * Add URI so the consumer output object. Set the correct path depending on the
439 * domain adding the default trace directory.
440 */
441 static int add_uri_to_consumer(struct consumer_output *consumer,
442 struct lttng_uri *uri, int domain, const char *session_name)
443 {
444 int ret = LTTNG_OK;
445 const char *default_trace_dir;
446
447 assert(uri);
448
449 if (consumer == NULL) {
450 DBG("No consumer detected. Don't add URI. Stopping.");
451 ret = LTTNG_ERR_NO_CONSUMER;
452 goto error;
453 }
454
455 switch (domain) {
456 case LTTNG_DOMAIN_KERNEL:
457 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
458 break;
459 case LTTNG_DOMAIN_UST:
460 default_trace_dir = DEFAULT_UST_TRACE_DIR;
461 break;
462 default:
463 /*
464 * This case is possible is we try to add the URI to the global tracing
465 * session consumer object which in this case there is no subdir.
466 */
467 default_trace_dir = "";
468 }
469
470 switch (uri->dtype) {
471 case LTTNG_DST_IPV4:
472 case LTTNG_DST_IPV6:
473 DBG2("Setting network URI to consumer");
474
475 if (consumer->type == CONSUMER_DST_NET) {
476 if ((uri->stype == LTTNG_STREAM_CONTROL &&
477 consumer->dst.net.control_isset) ||
478 (uri->stype == LTTNG_STREAM_DATA &&
479 consumer->dst.net.data_isset)) {
480 ret = LTTNG_ERR_URL_EXIST;
481 goto error;
482 }
483 } else {
484 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
485 }
486
487 consumer->type = CONSUMER_DST_NET;
488
489 /* Set URI into consumer output object */
490 ret = consumer_set_network_uri(consumer, uri);
491 if (ret < 0) {
492 ret = -ret;
493 goto error;
494 } else if (ret == 1) {
495 /*
496 * URI was the same in the consumer so we do not append the subdir
497 * again so to not duplicate output dir.
498 */
499 ret = LTTNG_OK;
500 goto error;
501 }
502
503 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
504 ret = consumer_set_subdir(consumer, session_name);
505 if (ret < 0) {
506 ret = LTTNG_ERR_FATAL;
507 goto error;
508 }
509 }
510
511 if (uri->stype == LTTNG_STREAM_CONTROL) {
512 /* On a new subdir, reappend the default trace dir. */
513 strncat(consumer->subdir, default_trace_dir,
514 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
515 DBG3("Append domain trace name to subdir %s", consumer->subdir);
516 }
517
518 break;
519 case LTTNG_DST_PATH:
520 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
521 memset(consumer->dst.trace_path, 0,
522 sizeof(consumer->dst.trace_path));
523 strncpy(consumer->dst.trace_path, uri->dst.path,
524 sizeof(consumer->dst.trace_path));
525 /* Append default trace dir */
526 strncat(consumer->dst.trace_path, default_trace_dir,
527 sizeof(consumer->dst.trace_path) -
528 strlen(consumer->dst.trace_path) - 1);
529 /* Flag consumer as local. */
530 consumer->type = CONSUMER_DST_LOCAL;
531 break;
532 }
533
534 ret = LTTNG_OK;
535
536 error:
537 return ret;
538 }
539
540 /*
541 * Init tracing by creating trace directory and sending fds kernel consumer.
542 */
543 static int init_kernel_tracing(struct ltt_kernel_session *session)
544 {
545 int ret = 0;
546 struct lttng_ht_iter iter;
547 struct consumer_socket *socket;
548
549 assert(session);
550
551 rcu_read_lock();
552
553 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
554 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
555 socket, node.node) {
556 pthread_mutex_lock(socket->lock);
557 ret = kernel_consumer_send_session(socket, session);
558 pthread_mutex_unlock(socket->lock);
559 if (ret < 0) {
560 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
561 goto error;
562 }
563 }
564 }
565
566 error:
567 rcu_read_unlock();
568 return ret;
569 }
570
571 /*
572 * Create a socket to the relayd using the URI.
573 *
574 * On success, the relayd_sock pointer is set to the created socket.
575 * Else, it's stays untouched and a lttcomm error code is returned.
576 */
577 static int create_connect_relayd(struct lttng_uri *uri,
578 struct lttcomm_relayd_sock **relayd_sock)
579 {
580 int ret;
581 struct lttcomm_relayd_sock *rsock;
582
583 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
584 RELAYD_VERSION_COMM_MINOR);
585 if (!rsock) {
586 ret = LTTNG_ERR_FATAL;
587 goto error;
588 }
589
590 /*
591 * Connect to relayd so we can proceed with a session creation. This call
592 * can possibly block for an arbitrary amount of time to set the health
593 * state to be in poll execution.
594 */
595 health_poll_entry();
596 ret = relayd_connect(rsock);
597 health_poll_exit();
598 if (ret < 0) {
599 ERR("Unable to reach lttng-relayd");
600 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
601 goto free_sock;
602 }
603
604 /* Create socket for control stream. */
605 if (uri->stype == LTTNG_STREAM_CONTROL) {
606 DBG3("Creating relayd stream socket from URI");
607
608 /* Check relayd version */
609 ret = relayd_version_check(rsock);
610 if (ret < 0) {
611 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
612 goto close_sock;
613 }
614 } else if (uri->stype == LTTNG_STREAM_DATA) {
615 DBG3("Creating relayd data socket from URI");
616 } else {
617 /* Command is not valid */
618 ERR("Relayd invalid stream type: %d", uri->stype);
619 ret = LTTNG_ERR_INVALID;
620 goto close_sock;
621 }
622
623 *relayd_sock = rsock;
624
625 return LTTNG_OK;
626
627 close_sock:
628 /* The returned value is not useful since we are on an error path. */
629 (void) relayd_close(rsock);
630 free_sock:
631 free(rsock);
632 error:
633 return ret;
634 }
635
636 /*
637 * Connect to the relayd using URI and send the socket to the right consumer.
638 */
639 static int send_consumer_relayd_socket(int domain, unsigned int session_id,
640 struct lttng_uri *relayd_uri, struct consumer_output *consumer,
641 struct consumer_socket *consumer_sock,
642 char *session_name, char *hostname, int session_live_timer)
643 {
644 int ret;
645 struct lttcomm_relayd_sock *rsock = NULL;
646
647 /* Connect to relayd and make version check if uri is the control. */
648 ret = create_connect_relayd(relayd_uri, &rsock);
649 if (ret != LTTNG_OK) {
650 goto error;
651 }
652 assert(rsock);
653
654 /* Set the network sequence index if not set. */
655 if (consumer->net_seq_index == (uint64_t) -1ULL) {
656 pthread_mutex_lock(&relayd_net_seq_idx_lock);
657 /*
658 * Increment net_seq_idx because we are about to transfer the
659 * new relayd socket to the consumer.
660 * Assign unique key so the consumer can match streams.
661 */
662 consumer->net_seq_index = ++relayd_net_seq_idx;
663 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
664 }
665
666 /* Send relayd socket to consumer. */
667 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
668 relayd_uri->stype, session_id,
669 session_name, hostname, session_live_timer);
670 if (ret < 0) {
671 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
672 goto close_sock;
673 }
674
675 /* Flag that the corresponding socket was sent. */
676 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
677 consumer_sock->control_sock_sent = 1;
678 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
679 consumer_sock->data_sock_sent = 1;
680 }
681
682 ret = LTTNG_OK;
683
684 /*
685 * Close socket which was dup on the consumer side. The session daemon does
686 * NOT keep track of the relayd socket(s) once transfer to the consumer.
687 */
688
689 close_sock:
690 (void) relayd_close(rsock);
691 free(rsock);
692
693 error:
694 if (ret != LTTNG_OK) {
695 /*
696 * The consumer output for this session should not be used anymore
697 * since the relayd connection failed thus making any tracing or/and
698 * streaming not usable.
699 */
700 consumer->enabled = 0;
701 }
702 return ret;
703 }
704
705 /*
706 * Send both relayd sockets to a specific consumer and domain. This is a
707 * helper function to facilitate sending the information to the consumer for a
708 * session.
709 */
710 static int send_consumer_relayd_sockets(int domain, unsigned int session_id,
711 struct consumer_output *consumer, struct consumer_socket *sock,
712 char *session_name, char *hostname, int session_live_timer)
713 {
714 int ret = LTTNG_OK;
715
716 assert(consumer);
717 assert(sock);
718
719 /* Sending control relayd socket. */
720 if (!sock->control_sock_sent) {
721 ret = send_consumer_relayd_socket(domain, session_id,
722 &consumer->dst.net.control, consumer, sock,
723 session_name, hostname, session_live_timer);
724 if (ret != LTTNG_OK) {
725 goto error;
726 }
727 }
728
729 /* Sending data relayd socket. */
730 if (!sock->data_sock_sent) {
731 ret = send_consumer_relayd_socket(domain, session_id,
732 &consumer->dst.net.data, consumer, sock,
733 session_name, hostname, session_live_timer);
734 if (ret != LTTNG_OK) {
735 goto error;
736 }
737 }
738
739 error:
740 return ret;
741 }
742
743 /*
744 * Setup relayd connections for a tracing session. First creates the socket to
745 * the relayd and send them to the right domain consumer. Consumer type MUST be
746 * network.
747 */
748 int cmd_setup_relayd(struct ltt_session *session)
749 {
750 int ret = LTTNG_OK;
751 struct ltt_ust_session *usess;
752 struct ltt_kernel_session *ksess;
753 struct consumer_socket *socket;
754 struct lttng_ht_iter iter;
755
756 assert(session);
757
758 usess = session->ust_session;
759 ksess = session->kernel_session;
760
761 DBG("Setting relayd for session %s", session->name);
762
763 rcu_read_lock();
764
765 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
766 && usess->consumer->enabled) {
767 /* For each consumer socket, send relayd sockets */
768 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
769 socket, node.node) {
770 pthread_mutex_lock(socket->lock);
771 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
772 usess->consumer, socket,
773 session->name, session->hostname,
774 session->live_timer);
775 pthread_mutex_unlock(socket->lock);
776 if (ret != LTTNG_OK) {
777 goto error;
778 }
779 /* Session is now ready for network streaming. */
780 session->net_handle = 1;
781 }
782 }
783
784 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
785 && ksess->consumer->enabled) {
786 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
787 socket, node.node) {
788 pthread_mutex_lock(socket->lock);
789 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
790 ksess->consumer, socket,
791 session->name, session->hostname,
792 session->live_timer);
793 pthread_mutex_unlock(socket->lock);
794 if (ret != LTTNG_OK) {
795 goto error;
796 }
797 /* Session is now ready for network streaming. */
798 session->net_handle = 1;
799 }
800 }
801
802 error:
803 rcu_read_unlock();
804 return ret;
805 }
806
807 /*
808 * Start a kernel session by opening all necessary streams.
809 */
810 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
811 {
812 int ret;
813 struct ltt_kernel_channel *kchan;
814
815 /* Open kernel metadata */
816 if (ksess->metadata == NULL && ksess->output_traces) {
817 ret = kernel_open_metadata(ksess);
818 if (ret < 0) {
819 ret = LTTNG_ERR_KERN_META_FAIL;
820 goto error;
821 }
822 }
823
824 /* Open kernel metadata stream */
825 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
826 ret = kernel_open_metadata_stream(ksess);
827 if (ret < 0) {
828 ERR("Kernel create metadata stream failed");
829 ret = LTTNG_ERR_KERN_STREAM_FAIL;
830 goto error;
831 }
832 }
833
834 /* For each channel */
835 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
836 if (kchan->stream_count == 0) {
837 ret = kernel_open_channel_stream(kchan);
838 if (ret < 0) {
839 ret = LTTNG_ERR_KERN_STREAM_FAIL;
840 goto error;
841 }
842 /* Update the stream global counter */
843 ksess->stream_count_global += ret;
844 }
845 }
846
847 /* Setup kernel consumer socket and send fds to it */
848 ret = init_kernel_tracing(ksess);
849 if (ret != 0) {
850 ret = LTTNG_ERR_KERN_START_FAIL;
851 goto error;
852 }
853
854 /* This start the kernel tracing */
855 ret = kernel_start_session(ksess);
856 if (ret < 0) {
857 ret = LTTNG_ERR_KERN_START_FAIL;
858 goto error;
859 }
860
861 /* Quiescent wait after starting trace */
862 kernel_wait_quiescent(kernel_tracer_fd);
863
864 ksess->active = 1;
865
866 ret = LTTNG_OK;
867
868 error:
869 return ret;
870 }
871
872 /*
873 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
874 */
875 int cmd_disable_channel(struct ltt_session *session, int domain,
876 char *channel_name)
877 {
878 int ret;
879 struct ltt_ust_session *usess;
880
881 usess = session->ust_session;
882
883 rcu_read_lock();
884
885 switch (domain) {
886 case LTTNG_DOMAIN_KERNEL:
887 {
888 ret = channel_kernel_disable(session->kernel_session,
889 channel_name);
890 if (ret != LTTNG_OK) {
891 goto error;
892 }
893
894 kernel_wait_quiescent(kernel_tracer_fd);
895 break;
896 }
897 case LTTNG_DOMAIN_UST:
898 {
899 struct ltt_ust_channel *uchan;
900 struct lttng_ht *chan_ht;
901
902 chan_ht = usess->domain_global.channels;
903
904 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
905 if (uchan == NULL) {
906 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
907 goto error;
908 }
909
910 ret = channel_ust_disable(usess, uchan);
911 if (ret != LTTNG_OK) {
912 goto error;
913 }
914 break;
915 }
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_TRACK_PID processed by the client thread.
930 *
931 * Called with session lock held.
932 */
933 int cmd_track_pid(struct ltt_session *session, int domain, int pid)
934 {
935 int ret;
936
937 rcu_read_lock();
938
939 switch (domain) {
940 case LTTNG_DOMAIN_KERNEL:
941 {
942 struct ltt_kernel_session *ksess;
943
944 ksess = session->kernel_session;
945
946 ret = kernel_track_pid(ksess, pid);
947 if (ret != LTTNG_OK) {
948 goto error;
949 }
950
951 kernel_wait_quiescent(kernel_tracer_fd);
952 break;
953 }
954 case LTTNG_DOMAIN_UST:
955 {
956 struct ltt_ust_session *usess;
957
958 usess = session->ust_session;
959
960 ret = trace_ust_track_pid(usess, pid);
961 if (ret != LTTNG_OK) {
962 goto error;
963 }
964 break;
965 }
966 default:
967 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
968 goto error;
969 }
970
971 ret = LTTNG_OK;
972
973 error:
974 rcu_read_unlock();
975 return ret;
976 }
977
978 /*
979 * Command LTTNG_UNTRACK_PID processed by the client thread.
980 *
981 * Called with session lock held.
982 */
983 int cmd_untrack_pid(struct ltt_session *session, int domain, int pid)
984 {
985 int ret;
986
987 rcu_read_lock();
988
989 switch (domain) {
990 case LTTNG_DOMAIN_KERNEL:
991 {
992 struct ltt_kernel_session *ksess;
993
994 ksess = session->kernel_session;
995
996 ret = kernel_untrack_pid(ksess, pid);
997 if (ret != LTTNG_OK) {
998 goto error;
999 }
1000
1001 kernel_wait_quiescent(kernel_tracer_fd);
1002 break;
1003 }
1004 case LTTNG_DOMAIN_UST:
1005 {
1006 struct ltt_ust_session *usess;
1007
1008 usess = session->ust_session;
1009
1010 ret = trace_ust_untrack_pid(usess, pid);
1011 if (ret != LTTNG_OK) {
1012 goto error;
1013 }
1014 break;
1015 }
1016 default:
1017 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1018 goto error;
1019 }
1020
1021 ret = LTTNG_OK;
1022
1023 error:
1024 rcu_read_unlock();
1025 return ret;
1026 }
1027
1028 /*
1029 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1030 *
1031 * The wpipe arguments is used as a notifier for the kernel thread.
1032 */
1033 int cmd_enable_channel(struct ltt_session *session,
1034 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1035 {
1036 int ret;
1037 struct ltt_ust_session *usess = session->ust_session;
1038 struct lttng_ht *chan_ht;
1039 size_t len;
1040
1041 assert(session);
1042 assert(attr);
1043 assert(domain);
1044
1045 len = strnlen(attr->name, sizeof(attr->name));
1046
1047 /* Validate channel name */
1048 if (attr->name[0] == '.' ||
1049 memchr(attr->name, '/', len) != NULL) {
1050 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1051 goto end;
1052 }
1053
1054 DBG("Enabling channel %s for session %s", attr->name, session->name);
1055
1056 rcu_read_lock();
1057
1058 /*
1059 * Don't try to enable a channel if the session has been started at
1060 * some point in time before. The tracer does not allow it.
1061 */
1062 if (session->has_been_started) {
1063 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1064 goto error;
1065 }
1066
1067 /*
1068 * If the session is a live session, remove the switch timer, the
1069 * live timer does the same thing but sends also synchronisation
1070 * beacons for inactive streams.
1071 */
1072 if (session->live_timer > 0) {
1073 attr->attr.live_timer_interval = session->live_timer;
1074 attr->attr.switch_timer_interval = 0;
1075 }
1076
1077 /*
1078 * The ringbuffer (both in user space and kernel) behave badly in overwrite
1079 * mode and with less than 2 subbuf so block it right away and send back an
1080 * invalid attribute error.
1081 */
1082 if (attr->attr.overwrite && attr->attr.num_subbuf < 2) {
1083 ret = LTTNG_ERR_INVALID;
1084 goto error;
1085 }
1086
1087 switch (domain->type) {
1088 case LTTNG_DOMAIN_KERNEL:
1089 {
1090 struct ltt_kernel_channel *kchan;
1091
1092 kchan = trace_kernel_get_channel_by_name(attr->name,
1093 session->kernel_session);
1094 if (kchan == NULL) {
1095 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1096 if (attr->name[0] != '\0') {
1097 session->kernel_session->has_non_default_channel = 1;
1098 }
1099 } else {
1100 ret = channel_kernel_enable(session->kernel_session, kchan);
1101 }
1102
1103 if (ret != LTTNG_OK) {
1104 goto error;
1105 }
1106
1107 kernel_wait_quiescent(kernel_tracer_fd);
1108 break;
1109 }
1110 case LTTNG_DOMAIN_UST:
1111 {
1112 struct ltt_ust_channel *uchan;
1113
1114 chan_ht = usess->domain_global.channels;
1115
1116 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1117 if (uchan == NULL) {
1118 ret = channel_ust_create(usess, attr, domain->buf_type);
1119 if (attr->name[0] != '\0') {
1120 usess->has_non_default_channel = 1;
1121 }
1122 } else {
1123 ret = channel_ust_enable(usess, uchan);
1124 }
1125 break;
1126 }
1127 default:
1128 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1129 goto error;
1130 }
1131
1132 error:
1133 rcu_read_unlock();
1134 end:
1135 return ret;
1136 }
1137
1138 /*
1139 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1140 */
1141 int cmd_disable_event(struct ltt_session *session, int domain,
1142 char *channel_name,
1143 struct lttng_event *event)
1144 {
1145 int ret;
1146 char *event_name;
1147
1148 DBG("Disable event command for event \'%s\'", event->name);
1149
1150 event_name = event->name;
1151 if (validate_event_name(event_name)) {
1152 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1153 goto error;
1154 }
1155
1156 /* Error out on unhandled search criteria */
1157 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1158 || event->pid || event->filter || event->exclusion) {
1159 ret = LTTNG_ERR_UNK;
1160 goto error;
1161 }
1162
1163 rcu_read_lock();
1164
1165 switch (domain) {
1166 case LTTNG_DOMAIN_KERNEL:
1167 {
1168 struct ltt_kernel_channel *kchan;
1169 struct ltt_kernel_session *ksess;
1170
1171 ksess = session->kernel_session;
1172
1173 /*
1174 * If a non-default channel has been created in the
1175 * session, explicitely require that -c chan_name needs
1176 * to be provided.
1177 */
1178 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1179 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1180 goto error_unlock;
1181 }
1182
1183 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1184 if (kchan == NULL) {
1185 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1186 goto error_unlock;
1187 }
1188
1189 switch (event->type) {
1190 case LTTNG_EVENT_ALL:
1191 ret = event_kernel_disable_event_all(kchan);
1192 if (ret != LTTNG_OK) {
1193 goto error_unlock;
1194 }
1195 break;
1196 case LTTNG_EVENT_TRACEPOINT: /* fall-through */
1197 case LTTNG_EVENT_SYSCALL:
1198 if (!strcmp(event_name, "*")) {
1199 ret = event_kernel_disable_event_type(kchan,
1200 event->type);
1201 } else {
1202 ret = event_kernel_disable_event(kchan,
1203 event_name);
1204 }
1205 if (ret != LTTNG_OK) {
1206 goto error_unlock;
1207 }
1208 break;
1209 case LTTNG_EVENT_PROBE:
1210 case LTTNG_EVENT_FUNCTION:
1211 case LTTNG_EVENT_FUNCTION_ENTRY:
1212 ret = event_kernel_disable_event(kchan, event_name);
1213 if (ret != LTTNG_OK) {
1214 goto error_unlock;
1215 }
1216 break;
1217 default:
1218 ret = LTTNG_ERR_UNK;
1219 goto error_unlock;
1220 }
1221
1222 kernel_wait_quiescent(kernel_tracer_fd);
1223 break;
1224 }
1225 case LTTNG_DOMAIN_UST:
1226 {
1227 struct ltt_ust_channel *uchan;
1228 struct ltt_ust_session *usess;
1229
1230 usess = session->ust_session;
1231
1232 if (validate_ust_event_name(event_name)) {
1233 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1234 goto error_unlock;
1235 }
1236
1237 /*
1238 * If a non-default channel has been created in the
1239 * session, explicitely require that -c chan_name needs
1240 * to be provided.
1241 */
1242 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1243 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1244 goto error_unlock;
1245 }
1246
1247 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1248 channel_name);
1249 if (uchan == NULL) {
1250 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1251 goto error_unlock;
1252 }
1253
1254 switch (event->type) {
1255 case LTTNG_EVENT_ALL:
1256 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
1257 if (ret != LTTNG_OK) {
1258 goto error_unlock;
1259 }
1260 break;
1261 default:
1262 ret = LTTNG_ERR_UNK;
1263 goto error_unlock;
1264 }
1265
1266 DBG3("Disable UST event %s in channel %s completed", event_name,
1267 channel_name);
1268 break;
1269 }
1270 case LTTNG_DOMAIN_LOG4J:
1271 case LTTNG_DOMAIN_JUL:
1272 case LTTNG_DOMAIN_PYTHON:
1273 {
1274 struct agent *agt;
1275 struct ltt_ust_session *usess = session->ust_session;
1276
1277 assert(usess);
1278
1279 switch (event->type) {
1280 case LTTNG_EVENT_ALL:
1281 break;
1282 default:
1283 ret = LTTNG_ERR_UNK;
1284 goto error_unlock;
1285 }
1286
1287 agt = trace_ust_find_agent(usess, domain);
1288 if (!agt) {
1289 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1290 goto error_unlock;
1291 }
1292 /* The wild card * means that everything should be disabled. */
1293 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1294 ret = event_agent_disable_all(usess, agt);
1295 } else {
1296 ret = event_agent_disable(usess, agt, event_name);
1297 }
1298 if (ret != LTTNG_OK) {
1299 goto error_unlock;
1300 }
1301
1302 break;
1303 }
1304 default:
1305 ret = LTTNG_ERR_UND;
1306 goto error_unlock;
1307 }
1308
1309 ret = LTTNG_OK;
1310
1311 error_unlock:
1312 rcu_read_unlock();
1313 error:
1314 return ret;
1315 }
1316
1317 /*
1318 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1319 */
1320 int cmd_add_context(struct ltt_session *session, int domain,
1321 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1322 {
1323 int ret, chan_kern_created = 0, chan_ust_created = 0;
1324
1325 switch (domain) {
1326 case LTTNG_DOMAIN_KERNEL:
1327 assert(session->kernel_session);
1328
1329 if (session->kernel_session->channel_count == 0) {
1330 /* Create default channel */
1331 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1332 if (ret != LTTNG_OK) {
1333 goto error;
1334 }
1335 chan_kern_created = 1;
1336 }
1337 /* Add kernel context to kernel tracer */
1338 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1339 if (ret != LTTNG_OK) {
1340 goto error;
1341 }
1342 break;
1343 case LTTNG_DOMAIN_UST:
1344 {
1345 struct ltt_ust_session *usess = session->ust_session;
1346 unsigned int chan_count;
1347
1348 assert(usess);
1349
1350 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1351 if (chan_count == 0) {
1352 struct lttng_channel *attr;
1353 /* Create default channel */
1354 attr = channel_new_default_attr(domain, usess->buffer_type);
1355 if (attr == NULL) {
1356 ret = LTTNG_ERR_FATAL;
1357 goto error;
1358 }
1359
1360 ret = channel_ust_create(usess, attr, usess->buffer_type);
1361 if (ret != LTTNG_OK) {
1362 free(attr);
1363 goto error;
1364 }
1365 free(attr);
1366 chan_ust_created = 1;
1367 }
1368
1369 ret = context_ust_add(usess, domain, ctx, channel_name);
1370 if (ret != LTTNG_OK) {
1371 goto error;
1372 }
1373 break;
1374 }
1375 default:
1376 ret = LTTNG_ERR_UND;
1377 goto error;
1378 }
1379
1380 return LTTNG_OK;
1381
1382 error:
1383 if (chan_kern_created) {
1384 struct ltt_kernel_channel *kchan =
1385 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1386 session->kernel_session);
1387 /* Created previously, this should NOT fail. */
1388 assert(kchan);
1389 kernel_destroy_channel(kchan);
1390 }
1391
1392 if (chan_ust_created) {
1393 struct ltt_ust_channel *uchan =
1394 trace_ust_find_channel_by_name(
1395 session->ust_session->domain_global.channels,
1396 DEFAULT_CHANNEL_NAME);
1397 /* Created previously, this should NOT fail. */
1398 assert(uchan);
1399 /* Remove from the channel list of the session. */
1400 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1401 uchan);
1402 trace_ust_destroy_channel(uchan);
1403 }
1404 return ret;
1405 }
1406
1407 static int validate_event_name(const char *name)
1408 {
1409 int ret = 0;
1410 const char *c = name;
1411 const char *event_name_end = c + LTTNG_SYMBOL_NAME_LEN;
1412
1413 /*
1414 * Make sure that unescaped wildcards are only used as the last
1415 * character of the event name.
1416 */
1417 while (c < event_name_end) {
1418 switch (*c) {
1419 case '\0':
1420 goto end;
1421 case '\\':
1422 c++;
1423 break;
1424 case '*':
1425 if ((c + 1) < event_name_end && *(c + 1)) {
1426 /* Wildcard is not the last character */
1427 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1428 goto end;
1429 }
1430 default:
1431 break;
1432 }
1433 c++;
1434 }
1435 end:
1436 return ret;
1437 }
1438
1439 static inline bool name_starts_with(const char *name, const char *prefix)
1440 {
1441 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1442
1443 return !strncmp(name, prefix, max_cmp_len);
1444 }
1445
1446 /* Perform userspace-specific event name validation */
1447 static int validate_ust_event_name(const char *name)
1448 {
1449 int ret = 0;
1450
1451 if (!name) {
1452 ret = -1;
1453 goto end;
1454 }
1455
1456 /*
1457 * Check name against all internal UST event component namespaces used
1458 * by the agents.
1459 */
1460 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1461 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1462 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1463 ret = -1;
1464 }
1465
1466 end:
1467 return ret;
1468 }
1469
1470 /*
1471 * Internal version of cmd_enable_event() with a supplemental
1472 * "internal_event" flag which is used to enable internal events which should
1473 * be hidden from clients. Such events are used in the agent implementation to
1474 * enable the events through which all "agent" events are funeled.
1475 */
1476 static int _cmd_enable_event(struct ltt_session *session,
1477 struct lttng_domain *domain,
1478 char *channel_name, struct lttng_event *event,
1479 char *filter_expression,
1480 struct lttng_filter_bytecode *filter,
1481 struct lttng_event_exclusion *exclusion,
1482 int wpipe, bool internal_event)
1483 {
1484 int ret, channel_created = 0;
1485 struct lttng_channel *attr;
1486
1487 assert(session);
1488 assert(event);
1489 assert(channel_name);
1490
1491 DBG("Enable event command for event \'%s\'", event->name);
1492
1493 ret = validate_event_name(event->name);
1494 if (ret) {
1495 goto error;
1496 }
1497
1498 rcu_read_lock();
1499
1500 switch (domain->type) {
1501 case LTTNG_DOMAIN_KERNEL:
1502 {
1503 struct ltt_kernel_channel *kchan;
1504
1505 /*
1506 * If a non-default channel has been created in the
1507 * session, explicitely require that -c chan_name needs
1508 * to be provided.
1509 */
1510 if (session->kernel_session->has_non_default_channel
1511 && channel_name[0] == '\0') {
1512 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1513 goto error;
1514 }
1515
1516 kchan = trace_kernel_get_channel_by_name(channel_name,
1517 session->kernel_session);
1518 if (kchan == NULL) {
1519 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1520 LTTNG_BUFFER_GLOBAL);
1521 if (attr == NULL) {
1522 ret = LTTNG_ERR_FATAL;
1523 goto error;
1524 }
1525 strncpy(attr->name, channel_name, sizeof(attr->name));
1526
1527 ret = cmd_enable_channel(session, domain, attr, wpipe);
1528 if (ret != LTTNG_OK) {
1529 free(attr);
1530 goto error;
1531 }
1532 free(attr);
1533
1534 channel_created = 1;
1535 }
1536
1537 /* Get the newly created kernel channel pointer */
1538 kchan = trace_kernel_get_channel_by_name(channel_name,
1539 session->kernel_session);
1540 if (kchan == NULL) {
1541 /* This sould not happen... */
1542 ret = LTTNG_ERR_FATAL;
1543 goto error;
1544 }
1545
1546 switch (event->type) {
1547 case LTTNG_EVENT_ALL:
1548 {
1549 char *filter_expression_a = NULL;
1550 struct lttng_filter_bytecode *filter_a = NULL;
1551
1552 /*
1553 * We need to duplicate filter_expression and filter,
1554 * because ownership is passed to first enable
1555 * event.
1556 */
1557 if (filter_expression) {
1558 filter_expression_a = strdup(filter_expression);
1559 if (!filter_expression_a) {
1560 ret = LTTNG_ERR_FATAL;
1561 goto error;
1562 }
1563 }
1564 if (filter) {
1565 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
1566 if (!filter_a) {
1567 free(filter_expression_a);
1568 ret = LTTNG_ERR_FATAL;
1569 goto error;
1570 }
1571 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
1572 }
1573 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
1574 ret = event_kernel_enable_event(kchan, event,
1575 filter_expression, filter);
1576 /* We have passed ownership */
1577 filter_expression = NULL;
1578 filter = NULL;
1579 if (ret != LTTNG_OK) {
1580 if (channel_created) {
1581 /* Let's not leak a useless channel. */
1582 kernel_destroy_channel(kchan);
1583 }
1584 free(filter_expression_a);
1585 free(filter_a);
1586 goto error;
1587 }
1588 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
1589 ret = event_kernel_enable_event(kchan, event,
1590 filter_expression_a, filter_a);
1591 if (ret != LTTNG_OK) {
1592 free(filter_expression_a);
1593 free(filter_a);
1594 goto error;
1595 }
1596 break;
1597 }
1598 case LTTNG_EVENT_PROBE:
1599 case LTTNG_EVENT_FUNCTION:
1600 case LTTNG_EVENT_FUNCTION_ENTRY:
1601 case LTTNG_EVENT_TRACEPOINT:
1602 ret = event_kernel_enable_event(kchan, event,
1603 filter_expression, filter);
1604 /* We have passed ownership */
1605 filter_expression = NULL;
1606 filter = NULL;
1607 if (ret != LTTNG_OK) {
1608 if (channel_created) {
1609 /* Let's not leak a useless channel. */
1610 kernel_destroy_channel(kchan);
1611 }
1612 goto error;
1613 }
1614 break;
1615 case LTTNG_EVENT_SYSCALL:
1616 ret = event_kernel_enable_event(kchan, event,
1617 filter_expression, filter);
1618 /* We have passed ownership */
1619 filter_expression = NULL;
1620 filter = NULL;
1621 if (ret != LTTNG_OK) {
1622 goto error;
1623 }
1624 break;
1625 default:
1626 ret = LTTNG_ERR_UNK;
1627 goto error;
1628 }
1629
1630 kernel_wait_quiescent(kernel_tracer_fd);
1631 break;
1632 }
1633 case LTTNG_DOMAIN_UST:
1634 {
1635 struct ltt_ust_channel *uchan;
1636 struct ltt_ust_session *usess = session->ust_session;
1637
1638 assert(usess);
1639
1640 /*
1641 * If a non-default channel has been created in the
1642 * session, explicitely require that -c chan_name needs
1643 * to be provided.
1644 */
1645 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1646 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1647 goto error;
1648 }
1649
1650 /* Get channel from global UST domain */
1651 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1652 channel_name);
1653 if (uchan == NULL) {
1654 /* Create default channel */
1655 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1656 usess->buffer_type);
1657 if (attr == NULL) {
1658 ret = LTTNG_ERR_FATAL;
1659 goto error;
1660 }
1661 strncpy(attr->name, channel_name, sizeof(attr->name));
1662
1663 ret = cmd_enable_channel(session, domain, attr, wpipe);
1664 if (ret != LTTNG_OK) {
1665 free(attr);
1666 goto error;
1667 }
1668 free(attr);
1669
1670 /* Get the newly created channel reference back */
1671 uchan = trace_ust_find_channel_by_name(
1672 usess->domain_global.channels, channel_name);
1673 assert(uchan);
1674 }
1675
1676 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
1677 /*
1678 * Don't allow users to add UST events to channels which
1679 * are assigned to a userspace subdomain (JUL, Log4J,
1680 * Python, etc.).
1681 */
1682 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
1683 goto error;
1684 }
1685
1686 if (!internal_event) {
1687 /*
1688 * Ensure the event name is not reserved for internal
1689 * use.
1690 */
1691 ret = validate_ust_event_name(event->name);
1692 if (ret) {
1693 WARN("Userspace event name %s failed validation.",
1694 event->name ?
1695 event->name : "NULL");
1696 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1697 goto error;
1698 }
1699 }
1700
1701 /* At this point, the session and channel exist on the tracer */
1702 ret = event_ust_enable_tracepoint(usess, uchan, event,
1703 filter_expression, filter, exclusion,
1704 internal_event);
1705 /* We have passed ownership */
1706 filter_expression = NULL;
1707 filter = NULL;
1708 exclusion = NULL;
1709 if (ret != LTTNG_OK) {
1710 goto error;
1711 }
1712 break;
1713 }
1714 case LTTNG_DOMAIN_LOG4J:
1715 case LTTNG_DOMAIN_JUL:
1716 case LTTNG_DOMAIN_PYTHON:
1717 {
1718 const char *default_event_name, *default_chan_name;
1719 struct agent *agt;
1720 struct lttng_event uevent;
1721 struct lttng_domain tmp_dom;
1722 struct ltt_ust_session *usess = session->ust_session;
1723
1724 assert(usess);
1725
1726 agt = trace_ust_find_agent(usess, domain->type);
1727 if (!agt) {
1728 agt = agent_create(domain->type);
1729 if (!agt) {
1730 ret = LTTNG_ERR_NOMEM;
1731 goto error;
1732 }
1733 agent_add(agt, usess->agents);
1734 }
1735
1736 /* Create the default tracepoint. */
1737 memset(&uevent, 0, sizeof(uevent));
1738 uevent.type = LTTNG_EVENT_TRACEPOINT;
1739 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
1740 default_event_name = event_get_default_agent_ust_name(domain->type);
1741 if (!default_event_name) {
1742 ret = LTTNG_ERR_FATAL;
1743 goto error;
1744 }
1745 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
1746 uevent.name[sizeof(uevent.name) - 1] = '\0';
1747
1748 /*
1749 * The domain type is changed because we are about to enable the
1750 * default channel and event for the JUL domain that are hardcoded.
1751 * This happens in the UST domain.
1752 */
1753 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
1754 tmp_dom.type = LTTNG_DOMAIN_UST;
1755
1756 switch (domain->type) {
1757 case LTTNG_DOMAIN_LOG4J:
1758 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
1759 break;
1760 case LTTNG_DOMAIN_JUL:
1761 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
1762 break;
1763 case LTTNG_DOMAIN_PYTHON:
1764 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
1765 break;
1766 default:
1767 /* The switch/case we are in should avoid this else big problem */
1768 assert(0);
1769 }
1770
1771 {
1772 struct lttng_filter_bytecode *filter_copy = NULL;
1773 char *filter_expression_copy = NULL;
1774
1775 if (filter) {
1776 filter_copy = zmalloc(
1777 sizeof(struct lttng_filter_bytecode)
1778 + filter->len);
1779 if (!filter_copy) {
1780 ret = LTTNG_ERR_NOMEM;
1781 goto error;
1782 }
1783
1784 memcpy(filter_copy, filter,
1785 sizeof(struct lttng_filter_bytecode)
1786 + filter->len);
1787 }
1788
1789 if (filter_expression) {
1790 filter_expression_copy =
1791 strdup(filter_expression);
1792 if (!filter_expression) {
1793 ret = LTTNG_ERR_NOMEM;
1794 goto error_free_copy;
1795 }
1796 }
1797
1798 ret = cmd_enable_event_internal(session, &tmp_dom,
1799 (char *) default_chan_name,
1800 &uevent, filter_expression_copy,
1801 filter_copy, NULL, wpipe);
1802 filter_copy = NULL;
1803 filter_expression_copy = NULL;
1804 error_free_copy:
1805 free(filter_copy);
1806 free(filter_expression_copy);
1807 }
1808
1809 if (ret != LTTNG_OK && ret != LTTNG_ERR_UST_EVENT_ENABLED) {
1810 goto error;
1811 }
1812
1813 /* The wild card * means that everything should be enabled. */
1814 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1815 ret = event_agent_enable_all(usess, agt, event, filter,
1816 filter_expression);
1817 filter = NULL;
1818 } else {
1819 ret = event_agent_enable(usess, agt, event, filter,
1820 filter_expression);
1821 filter = NULL;
1822 }
1823 if (ret != LTTNG_OK) {
1824 goto error;
1825 }
1826
1827 break;
1828 }
1829 default:
1830 ret = LTTNG_ERR_UND;
1831 goto error;
1832 }
1833
1834 ret = LTTNG_OK;
1835
1836 error:
1837 free(filter_expression);
1838 free(filter);
1839 free(exclusion);
1840 rcu_read_unlock();
1841 return ret;
1842 }
1843
1844 /*
1845 * Command LTTNG_ENABLE_EVENT processed by the client thread.
1846 * We own filter, exclusion, and filter_expression.
1847 */
1848 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1849 char *channel_name, struct lttng_event *event,
1850 char *filter_expression,
1851 struct lttng_filter_bytecode *filter,
1852 struct lttng_event_exclusion *exclusion,
1853 int wpipe)
1854 {
1855 return _cmd_enable_event(session, domain, channel_name, event,
1856 filter_expression, filter, exclusion, wpipe, false);
1857 }
1858
1859 /*
1860 * Enable an event which is internal to LTTng. An internal should
1861 * never be made visible to clients and are immune to checks such as
1862 * reserved names.
1863 */
1864 static int cmd_enable_event_internal(struct ltt_session *session,
1865 struct lttng_domain *domain,
1866 char *channel_name, struct lttng_event *event,
1867 char *filter_expression,
1868 struct lttng_filter_bytecode *filter,
1869 struct lttng_event_exclusion *exclusion,
1870 int wpipe)
1871 {
1872 return _cmd_enable_event(session, domain, channel_name, event,
1873 filter_expression, filter, exclusion, wpipe, true);
1874 }
1875
1876 /*
1877 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1878 */
1879 ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
1880 {
1881 int ret;
1882 ssize_t nb_events = 0;
1883
1884 switch (domain) {
1885 case LTTNG_DOMAIN_KERNEL:
1886 nb_events = kernel_list_events(kernel_tracer_fd, events);
1887 if (nb_events < 0) {
1888 ret = LTTNG_ERR_KERN_LIST_FAIL;
1889 goto error;
1890 }
1891 break;
1892 case LTTNG_DOMAIN_UST:
1893 nb_events = ust_app_list_events(events);
1894 if (nb_events < 0) {
1895 ret = LTTNG_ERR_UST_LIST_FAIL;
1896 goto error;
1897 }
1898 break;
1899 case LTTNG_DOMAIN_LOG4J:
1900 case LTTNG_DOMAIN_JUL:
1901 case LTTNG_DOMAIN_PYTHON:
1902 nb_events = agent_list_events(events, domain);
1903 if (nb_events < 0) {
1904 ret = LTTNG_ERR_UST_LIST_FAIL;
1905 goto error;
1906 }
1907 break;
1908 default:
1909 ret = LTTNG_ERR_UND;
1910 goto error;
1911 }
1912
1913 return nb_events;
1914
1915 error:
1916 /* Return negative value to differentiate return code */
1917 return -ret;
1918 }
1919
1920 /*
1921 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1922 */
1923 ssize_t cmd_list_tracepoint_fields(int domain,
1924 struct lttng_event_field **fields)
1925 {
1926 int ret;
1927 ssize_t nb_fields = 0;
1928
1929 switch (domain) {
1930 case LTTNG_DOMAIN_UST:
1931 nb_fields = ust_app_list_event_fields(fields);
1932 if (nb_fields < 0) {
1933 ret = LTTNG_ERR_UST_LIST_FAIL;
1934 goto error;
1935 }
1936 break;
1937 case LTTNG_DOMAIN_KERNEL:
1938 default: /* fall-through */
1939 ret = LTTNG_ERR_UND;
1940 goto error;
1941 }
1942
1943 return nb_fields;
1944
1945 error:
1946 /* Return negative value to differentiate return code */
1947 return -ret;
1948 }
1949
1950 ssize_t cmd_list_syscalls(struct lttng_event **events)
1951 {
1952 return syscall_table_list(events);
1953 }
1954
1955 /*
1956 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
1957 *
1958 * Called with session lock held.
1959 */
1960 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
1961 int domain, int32_t **pids)
1962 {
1963 int ret;
1964 ssize_t nr_pids = 0;
1965
1966 switch (domain) {
1967 case LTTNG_DOMAIN_KERNEL:
1968 {
1969 struct ltt_kernel_session *ksess;
1970
1971 ksess = session->kernel_session;
1972 nr_pids = kernel_list_tracker_pids(ksess, pids);
1973 if (nr_pids < 0) {
1974 ret = LTTNG_ERR_KERN_LIST_FAIL;
1975 goto error;
1976 }
1977 break;
1978 }
1979 case LTTNG_DOMAIN_UST:
1980 {
1981 struct ltt_ust_session *usess;
1982
1983 usess = session->ust_session;
1984 nr_pids = trace_ust_list_tracker_pids(usess, pids);
1985 if (nr_pids < 0) {
1986 ret = LTTNG_ERR_UST_LIST_FAIL;
1987 goto error;
1988 }
1989 break;
1990 }
1991 case LTTNG_DOMAIN_LOG4J:
1992 case LTTNG_DOMAIN_JUL:
1993 case LTTNG_DOMAIN_PYTHON:
1994 default:
1995 ret = LTTNG_ERR_UND;
1996 goto error;
1997 }
1998
1999 return nr_pids;
2000
2001 error:
2002 /* Return negative value to differentiate return code */
2003 return -ret;
2004 }
2005
2006 /*
2007 * Command LTTNG_START_TRACE processed by the client thread.
2008 *
2009 * Called with session mutex held.
2010 */
2011 int cmd_start_trace(struct ltt_session *session)
2012 {
2013 int ret;
2014 unsigned long nb_chan = 0;
2015 struct ltt_kernel_session *ksession;
2016 struct ltt_ust_session *usess;
2017
2018 assert(session);
2019
2020 /* Ease our life a bit ;) */
2021 ksession = session->kernel_session;
2022 usess = session->ust_session;
2023
2024 /* Is the session already started? */
2025 if (session->active) {
2026 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2027 goto error;
2028 }
2029
2030 /*
2031 * Starting a session without channel is useless since after that it's not
2032 * possible to enable channel thus inform the client.
2033 */
2034 if (usess && usess->domain_global.channels) {
2035 rcu_read_lock();
2036 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2037 rcu_read_unlock();
2038 }
2039 if (ksession) {
2040 nb_chan += ksession->channel_count;
2041 }
2042 if (!nb_chan) {
2043 ret = LTTNG_ERR_NO_CHANNEL;
2044 goto error;
2045 }
2046
2047 /* Kernel tracing */
2048 if (ksession != NULL) {
2049 ret = start_kernel_session(ksession, kernel_tracer_fd);
2050 if (ret != LTTNG_OK) {
2051 goto error;
2052 }
2053 }
2054
2055 /* Flag session that trace should start automatically */
2056 if (usess) {
2057 /*
2058 * Even though the start trace might fail, flag this session active so
2059 * other application coming in are started by default.
2060 */
2061 usess->active = 1;
2062
2063 ret = ust_app_start_trace_all(usess);
2064 if (ret < 0) {
2065 ret = LTTNG_ERR_UST_START_FAIL;
2066 goto error;
2067 }
2068 }
2069
2070 /* Flag this after a successful start. */
2071 session->has_been_started = 1;
2072 session->active = 1;
2073
2074 ret = LTTNG_OK;
2075
2076 error:
2077 return ret;
2078 }
2079
2080 /*
2081 * Command LTTNG_STOP_TRACE processed by the client thread.
2082 */
2083 int cmd_stop_trace(struct ltt_session *session)
2084 {
2085 int ret;
2086 struct ltt_kernel_channel *kchan;
2087 struct ltt_kernel_session *ksession;
2088 struct ltt_ust_session *usess;
2089
2090 assert(session);
2091
2092 /* Short cut */
2093 ksession = session->kernel_session;
2094 usess = session->ust_session;
2095
2096 /* Session is not active. Skip everythong and inform the client. */
2097 if (!session->active) {
2098 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2099 goto error;
2100 }
2101
2102 /* Kernel tracer */
2103 if (ksession && ksession->active) {
2104 DBG("Stop kernel tracing");
2105
2106 /* Flush metadata if exist */
2107 if (ksession->metadata_stream_fd >= 0) {
2108 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2109 if (ret < 0) {
2110 ERR("Kernel metadata flush failed");
2111 }
2112 }
2113
2114 /* Flush all buffers before stopping */
2115 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2116 ret = kernel_flush_buffer(kchan);
2117 if (ret < 0) {
2118 ERR("Kernel flush buffer error");
2119 }
2120 }
2121
2122 ret = kernel_stop_session(ksession);
2123 if (ret < 0) {
2124 ret = LTTNG_ERR_KERN_STOP_FAIL;
2125 goto error;
2126 }
2127
2128 kernel_wait_quiescent(kernel_tracer_fd);
2129
2130 ksession->active = 0;
2131 }
2132
2133 if (usess && usess->active) {
2134 /*
2135 * Even though the stop trace might fail, flag this session inactive so
2136 * other application coming in are not started by default.
2137 */
2138 usess->active = 0;
2139
2140 ret = ust_app_stop_trace_all(usess);
2141 if (ret < 0) {
2142 ret = LTTNG_ERR_UST_STOP_FAIL;
2143 goto error;
2144 }
2145 }
2146
2147 /* Flag inactive after a successful stop. */
2148 session->active = 0;
2149 ret = LTTNG_OK;
2150
2151 error:
2152 return ret;
2153 }
2154
2155 /*
2156 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2157 */
2158 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2159 struct lttng_uri *uris)
2160 {
2161 int ret, i;
2162 struct ltt_kernel_session *ksess = session->kernel_session;
2163 struct ltt_ust_session *usess = session->ust_session;
2164
2165 assert(session);
2166 assert(uris);
2167 assert(nb_uri > 0);
2168
2169 /* Can't set consumer URI if the session is active. */
2170 if (session->active) {
2171 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2172 goto error;
2173 }
2174
2175 /* Set the "global" consumer URIs */
2176 for (i = 0; i < nb_uri; i++) {
2177 ret = add_uri_to_consumer(session->consumer,
2178 &uris[i], 0, session->name);
2179 if (ret != LTTNG_OK) {
2180 goto error;
2181 }
2182 }
2183
2184 /* Set UST session URIs */
2185 if (session->ust_session) {
2186 for (i = 0; i < nb_uri; i++) {
2187 ret = add_uri_to_consumer(
2188 session->ust_session->consumer,
2189 &uris[i], LTTNG_DOMAIN_UST,
2190 session->name);
2191 if (ret != LTTNG_OK) {
2192 goto error;
2193 }
2194 }
2195 }
2196
2197 /* Set kernel session URIs */
2198 if (session->kernel_session) {
2199 for (i = 0; i < nb_uri; i++) {
2200 ret = add_uri_to_consumer(
2201 session->kernel_session->consumer,
2202 &uris[i], LTTNG_DOMAIN_KERNEL,
2203 session->name);
2204 if (ret != LTTNG_OK) {
2205 goto error;
2206 }
2207 }
2208 }
2209
2210 /*
2211 * Make sure to set the session in output mode after we set URI since a
2212 * session can be created without URL (thus flagged in no output mode).
2213 */
2214 session->output_traces = 1;
2215 if (ksess) {
2216 ksess->output_traces = 1;
2217 }
2218
2219 if (usess) {
2220 usess->output_traces = 1;
2221 }
2222
2223 /* All good! */
2224 ret = LTTNG_OK;
2225
2226 error:
2227 return ret;
2228 }
2229
2230 /*
2231 * Command LTTNG_CREATE_SESSION processed by the client thread.
2232 */
2233 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
2234 size_t nb_uri, lttng_sock_cred *creds, unsigned int live_timer)
2235 {
2236 int ret;
2237 struct ltt_session *session;
2238
2239 assert(name);
2240 assert(creds);
2241
2242 /*
2243 * Verify if the session already exist
2244 *
2245 * XXX: There is no need for the session lock list here since the caller
2246 * (process_client_msg) is holding it. We might want to change that so a
2247 * single command does not lock the entire session list.
2248 */
2249 session = session_find_by_name(name);
2250 if (session != NULL) {
2251 ret = LTTNG_ERR_EXIST_SESS;
2252 goto find_error;
2253 }
2254
2255 /* Create tracing session in the registry */
2256 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
2257 LTTNG_SOCK_GET_GID_CRED(creds));
2258 if (ret != LTTNG_OK) {
2259 goto session_error;
2260 }
2261
2262 /*
2263 * Get the newly created session pointer back
2264 *
2265 * XXX: There is no need for the session lock list here since the caller
2266 * (process_client_msg) is holding it. We might want to change that so a
2267 * single command does not lock the entire session list.
2268 */
2269 session = session_find_by_name(name);
2270 assert(session);
2271
2272 session->live_timer = live_timer;
2273 /* Create default consumer output for the session not yet created. */
2274 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
2275 if (session->consumer == NULL) {
2276 ret = LTTNG_ERR_FATAL;
2277 goto consumer_error;
2278 }
2279
2280 if (uris) {
2281 ret = cmd_set_consumer_uri(session, nb_uri, uris);
2282 if (ret != LTTNG_OK) {
2283 goto consumer_error;
2284 }
2285 session->output_traces = 1;
2286 } else {
2287 session->output_traces = 0;
2288 DBG2("Session %s created with no output", session->name);
2289 }
2290
2291 session->consumer->enabled = 1;
2292
2293 return LTTNG_OK;
2294
2295 consumer_error:
2296 session_destroy(session);
2297 session_error:
2298 find_error:
2299 return ret;
2300 }
2301
2302 /*
2303 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
2304 */
2305 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
2306 size_t nb_uri, lttng_sock_cred *creds)
2307 {
2308 int ret;
2309 struct ltt_session *session;
2310 struct snapshot_output *new_output = NULL;
2311
2312 assert(name);
2313 assert(creds);
2314
2315 /*
2316 * Create session in no output mode with URIs set to NULL. The uris we've
2317 * received are for a default snapshot output if one.
2318 */
2319 ret = cmd_create_session_uri(name, NULL, 0, creds, -1);
2320 if (ret != LTTNG_OK) {
2321 goto error;
2322 }
2323
2324 /* Get the newly created session pointer back. This should NEVER fail. */
2325 session = session_find_by_name(name);
2326 assert(session);
2327
2328 /* Flag session for snapshot mode. */
2329 session->snapshot_mode = 1;
2330
2331 /* Skip snapshot output creation if no URI is given. */
2332 if (nb_uri == 0) {
2333 goto end;
2334 }
2335
2336 new_output = snapshot_output_alloc();
2337 if (!new_output) {
2338 ret = LTTNG_ERR_NOMEM;
2339 goto error_snapshot_alloc;
2340 }
2341
2342 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
2343 uris, nb_uri, session->consumer, new_output, &session->snapshot);
2344 if (ret < 0) {
2345 if (ret == -ENOMEM) {
2346 ret = LTTNG_ERR_NOMEM;
2347 } else {
2348 ret = LTTNG_ERR_INVALID;
2349 }
2350 goto error_snapshot;
2351 }
2352
2353 rcu_read_lock();
2354 snapshot_add_output(&session->snapshot, new_output);
2355 rcu_read_unlock();
2356
2357 end:
2358 return LTTNG_OK;
2359
2360 error_snapshot:
2361 snapshot_output_destroy(new_output);
2362 error_snapshot_alloc:
2363 session_destroy(session);
2364 error:
2365 return ret;
2366 }
2367
2368 /*
2369 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2370 *
2371 * Called with session lock held.
2372 */
2373 int cmd_destroy_session(struct ltt_session *session, int wpipe)
2374 {
2375 int ret;
2376 struct ltt_ust_session *usess;
2377 struct ltt_kernel_session *ksess;
2378
2379 /* Safety net */
2380 assert(session);
2381
2382 usess = session->ust_session;
2383 ksess = session->kernel_session;
2384
2385 /* Clean kernel session teardown */
2386 kernel_destroy_session(ksess);
2387
2388 /* UST session teardown */
2389 if (usess) {
2390 /* Close any relayd session */
2391 consumer_output_send_destroy_relayd(usess->consumer);
2392
2393 /* Destroy every UST application related to this session. */
2394 ret = ust_app_destroy_trace_all(usess);
2395 if (ret) {
2396 ERR("Error in ust_app_destroy_trace_all");
2397 }
2398
2399 /* Clean up the rest. */
2400 trace_ust_destroy_session(usess);
2401 }
2402
2403 /*
2404 * Must notify the kernel thread here to update it's poll set in order to
2405 * remove the channel(s)' fd just destroyed.
2406 */
2407 ret = notify_thread_pipe(wpipe);
2408 if (ret < 0) {
2409 PERROR("write kernel poll pipe");
2410 }
2411
2412 ret = session_destroy(session);
2413
2414 return ret;
2415 }
2416
2417 /*
2418 * Command LTTNG_CALIBRATE processed by the client thread.
2419 */
2420 int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2421 {
2422 int ret;
2423
2424 switch (domain) {
2425 case LTTNG_DOMAIN_KERNEL:
2426 {
2427 struct lttng_kernel_calibrate kcalibrate;
2428
2429 switch (calibrate->type) {
2430 case LTTNG_CALIBRATE_FUNCTION:
2431 default:
2432 /* Default and only possible calibrate option. */
2433 kcalibrate.type = LTTNG_KERNEL_CALIBRATE_KRETPROBE;
2434 break;
2435 }
2436
2437 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2438 if (ret < 0) {
2439 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
2440 goto error;
2441 }
2442 break;
2443 }
2444 case LTTNG_DOMAIN_UST:
2445 {
2446 struct lttng_ust_calibrate ucalibrate;
2447
2448 switch (calibrate->type) {
2449 case LTTNG_CALIBRATE_FUNCTION:
2450 default:
2451 /* Default and only possible calibrate option. */
2452 ucalibrate.type = LTTNG_UST_CALIBRATE_TRACEPOINT;
2453 break;
2454 }
2455
2456 ret = ust_app_calibrate_glb(&ucalibrate);
2457 if (ret < 0) {
2458 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
2459 goto error;
2460 }
2461 break;
2462 }
2463 default:
2464 ret = LTTNG_ERR_UND;
2465 goto error;
2466 }
2467
2468 ret = LTTNG_OK;
2469
2470 error:
2471 return ret;
2472 }
2473
2474 /*
2475 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2476 */
2477 int cmd_register_consumer(struct ltt_session *session, int domain,
2478 const char *sock_path, struct consumer_data *cdata)
2479 {
2480 int ret, sock;
2481 struct consumer_socket *socket = NULL;
2482
2483 assert(session);
2484 assert(cdata);
2485 assert(sock_path);
2486
2487 switch (domain) {
2488 case LTTNG_DOMAIN_KERNEL:
2489 {
2490 struct ltt_kernel_session *ksess = session->kernel_session;
2491
2492 assert(ksess);
2493
2494 /* Can't register a consumer if there is already one */
2495 if (ksess->consumer_fds_sent != 0) {
2496 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2497 goto error;
2498 }
2499
2500 sock = lttcomm_connect_unix_sock(sock_path);
2501 if (sock < 0) {
2502 ret = LTTNG_ERR_CONNECT_FAIL;
2503 goto error;
2504 }
2505 cdata->cmd_sock = sock;
2506
2507 socket = consumer_allocate_socket(&cdata->cmd_sock);
2508 if (socket == NULL) {
2509 ret = close(sock);
2510 if (ret < 0) {
2511 PERROR("close register consumer");
2512 }
2513 cdata->cmd_sock = -1;
2514 ret = LTTNG_ERR_FATAL;
2515 goto error;
2516 }
2517
2518 socket->lock = zmalloc(sizeof(pthread_mutex_t));
2519 if (socket->lock == NULL) {
2520 PERROR("zmalloc pthread mutex");
2521 ret = LTTNG_ERR_FATAL;
2522 goto error;
2523 }
2524 pthread_mutex_init(socket->lock, NULL);
2525 socket->registered = 1;
2526
2527 rcu_read_lock();
2528 consumer_add_socket(socket, ksess->consumer);
2529 rcu_read_unlock();
2530
2531 pthread_mutex_lock(&cdata->pid_mutex);
2532 cdata->pid = -1;
2533 pthread_mutex_unlock(&cdata->pid_mutex);
2534
2535 break;
2536 }
2537 default:
2538 /* TODO: Userspace tracing */
2539 ret = LTTNG_ERR_UND;
2540 goto error;
2541 }
2542
2543 return LTTNG_OK;
2544
2545 error:
2546 if (socket) {
2547 consumer_destroy_socket(socket);
2548 }
2549 return ret;
2550 }
2551
2552 /*
2553 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2554 */
2555 ssize_t cmd_list_domains(struct ltt_session *session,
2556 struct lttng_domain **domains)
2557 {
2558 int ret, index = 0;
2559 ssize_t nb_dom = 0;
2560 struct agent *agt;
2561 struct lttng_ht_iter iter;
2562
2563 if (session->kernel_session != NULL) {
2564 DBG3("Listing domains found kernel domain");
2565 nb_dom++;
2566 }
2567
2568 if (session->ust_session != NULL) {
2569 DBG3("Listing domains found UST global domain");
2570 nb_dom++;
2571
2572 rcu_read_lock();
2573 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2574 agt, node.node) {
2575 if (agt->being_used) {
2576 nb_dom++;
2577 }
2578 }
2579 rcu_read_unlock();
2580 }
2581
2582 if (!nb_dom) {
2583 goto end;
2584 }
2585
2586 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2587 if (*domains == NULL) {
2588 ret = LTTNG_ERR_FATAL;
2589 goto error;
2590 }
2591
2592 if (session->kernel_session != NULL) {
2593 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2594
2595 /* Kernel session buffer type is always GLOBAL */
2596 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
2597
2598 index++;
2599 }
2600
2601 if (session->ust_session != NULL) {
2602 (*domains)[index].type = LTTNG_DOMAIN_UST;
2603 (*domains)[index].buf_type = session->ust_session->buffer_type;
2604 index++;
2605
2606 rcu_read_lock();
2607 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2608 agt, node.node) {
2609 if (agt->being_used) {
2610 (*domains)[index].type = agt->domain;
2611 (*domains)[index].buf_type = session->ust_session->buffer_type;
2612 index++;
2613 }
2614 }
2615 rcu_read_unlock();
2616 }
2617 end:
2618 return nb_dom;
2619
2620 error:
2621 /* Return negative value to differentiate return code */
2622 return -ret;
2623 }
2624
2625
2626 /*
2627 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2628 */
2629 ssize_t cmd_list_channels(int domain, struct ltt_session *session,
2630 struct lttng_channel **channels)
2631 {
2632 int ret;
2633 ssize_t nb_chan = 0;
2634
2635 switch (domain) {
2636 case LTTNG_DOMAIN_KERNEL:
2637 if (session->kernel_session != NULL) {
2638 nb_chan = session->kernel_session->channel_count;
2639 }
2640 DBG3("Number of kernel channels %zd", nb_chan);
2641 if (nb_chan <= 0) {
2642 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
2643 }
2644 break;
2645 case LTTNG_DOMAIN_UST:
2646 if (session->ust_session != NULL) {
2647 rcu_read_lock();
2648 nb_chan = lttng_ht_get_count(
2649 session->ust_session->domain_global.channels);
2650 rcu_read_unlock();
2651 }
2652 DBG3("Number of UST global channels %zd", nb_chan);
2653 if (nb_chan < 0) {
2654 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2655 goto error;
2656 }
2657 break;
2658 default:
2659 ret = LTTNG_ERR_UND;
2660 goto error;
2661 }
2662
2663 if (nb_chan > 0) {
2664 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
2665 if (*channels == NULL) {
2666 ret = LTTNG_ERR_FATAL;
2667 goto error;
2668 }
2669
2670 list_lttng_channels(domain, session, *channels);
2671 }
2672
2673 return nb_chan;
2674
2675 error:
2676 /* Return negative value to differentiate return code */
2677 return -ret;
2678 }
2679
2680 /*
2681 * Command LTTNG_LIST_EVENTS processed by the client thread.
2682 */
2683 ssize_t cmd_list_events(int domain, struct ltt_session *session,
2684 char *channel_name, struct lttng_event **events)
2685 {
2686 int ret = 0;
2687 ssize_t nb_event = 0;
2688
2689 switch (domain) {
2690 case LTTNG_DOMAIN_KERNEL:
2691 if (session->kernel_session != NULL) {
2692 nb_event = list_lttng_kernel_events(channel_name,
2693 session->kernel_session, events);
2694 }
2695 break;
2696 case LTTNG_DOMAIN_UST:
2697 {
2698 if (session->ust_session != NULL) {
2699 nb_event = list_lttng_ust_global_events(channel_name,
2700 &session->ust_session->domain_global, events);
2701 }
2702 break;
2703 }
2704 case LTTNG_DOMAIN_LOG4J:
2705 case LTTNG_DOMAIN_JUL:
2706 case LTTNG_DOMAIN_PYTHON:
2707 if (session->ust_session) {
2708 struct lttng_ht_iter iter;
2709 struct agent *agt;
2710
2711 rcu_read_lock();
2712 cds_lfht_for_each_entry(session->ust_session->agents->ht,
2713 &iter.iter, agt, node.node) {
2714 nb_event = list_lttng_agent_events(agt, events);
2715 }
2716 rcu_read_unlock();
2717 }
2718 break;
2719 default:
2720 ret = LTTNG_ERR_UND;
2721 goto error;
2722 }
2723
2724 return nb_event;
2725
2726 error:
2727 /* Return negative value to differentiate return code */
2728 return -ret;
2729 }
2730
2731 /*
2732 * Using the session list, filled a lttng_session array to send back to the
2733 * client for session listing.
2734 *
2735 * The session list lock MUST be acquired before calling this function. Use
2736 * session_lock_list() and session_unlock_list().
2737 */
2738 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2739 gid_t gid)
2740 {
2741 int ret;
2742 unsigned int i = 0;
2743 struct ltt_session *session;
2744 struct ltt_session_list *list = session_get_list();
2745
2746 DBG("Getting all available session for UID %d GID %d",
2747 uid, gid);
2748 /*
2749 * Iterate over session list and append data after the control struct in
2750 * the buffer.
2751 */
2752 cds_list_for_each_entry(session, &list->head, list) {
2753 /*
2754 * Only list the sessions the user can control.
2755 */
2756 if (!session_access_ok(session, uid, gid)) {
2757 continue;
2758 }
2759
2760 struct ltt_kernel_session *ksess = session->kernel_session;
2761 struct ltt_ust_session *usess = session->ust_session;
2762
2763 if (session->consumer->type == CONSUMER_DST_NET ||
2764 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2765 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2766 ret = build_network_session_path(sessions[i].path,
2767 sizeof(sessions[i].path), session);
2768 } else {
2769 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
2770 session->consumer->dst.trace_path);
2771 }
2772 if (ret < 0) {
2773 PERROR("snprintf session path");
2774 continue;
2775 }
2776
2777 strncpy(sessions[i].name, session->name, NAME_MAX);
2778 sessions[i].name[NAME_MAX - 1] = '\0';
2779 sessions[i].enabled = session->active;
2780 sessions[i].snapshot_mode = session->snapshot_mode;
2781 sessions[i].live_timer_interval = session->live_timer;
2782 i++;
2783 }
2784 }
2785
2786 /*
2787 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2788 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
2789 */
2790 int cmd_data_pending(struct ltt_session *session)
2791 {
2792 int ret;
2793 struct ltt_kernel_session *ksess = session->kernel_session;
2794 struct ltt_ust_session *usess = session->ust_session;
2795
2796 assert(session);
2797
2798 /* Session MUST be stopped to ask for data availability. */
2799 if (session->active) {
2800 ret = LTTNG_ERR_SESSION_STARTED;
2801 goto error;
2802 } else {
2803 /*
2804 * If stopped, just make sure we've started before else the above call
2805 * will always send that there is data pending.
2806 *
2807 * The consumer assumes that when the data pending command is received,
2808 * the trace has been started before or else no output data is written
2809 * by the streams which is a condition for data pending. So, this is
2810 * *VERY* important that we don't ask the consumer before a start
2811 * trace.
2812 */
2813 if (!session->has_been_started) {
2814 ret = 0;
2815 goto error;
2816 }
2817 }
2818
2819 if (ksess && ksess->consumer) {
2820 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2821 if (ret == 1) {
2822 /* Data is still being extracted for the kernel. */
2823 goto error;
2824 }
2825 }
2826
2827 if (usess && usess->consumer) {
2828 ret = consumer_is_data_pending(usess->id, usess->consumer);
2829 if (ret == 1) {
2830 /* Data is still being extracted for the kernel. */
2831 goto error;
2832 }
2833 }
2834
2835 /* Data is ready to be read by a viewer */
2836 ret = 0;
2837
2838 error:
2839 return ret;
2840 }
2841
2842 /*
2843 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
2844 *
2845 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2846 */
2847 int cmd_snapshot_add_output(struct ltt_session *session,
2848 struct lttng_snapshot_output *output, uint32_t *id)
2849 {
2850 int ret;
2851 struct snapshot_output *new_output;
2852
2853 assert(session);
2854 assert(output);
2855
2856 DBG("Cmd snapshot add output for session %s", session->name);
2857
2858 /*
2859 * Permission denied to create an output if the session is not
2860 * set in no output mode.
2861 */
2862 if (session->output_traces) {
2863 ret = LTTNG_ERR_EPERM;
2864 goto error;
2865 }
2866
2867 /* Only one output is allowed until we have the "tee" feature. */
2868 if (session->snapshot.nb_output == 1) {
2869 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
2870 goto error;
2871 }
2872
2873 new_output = snapshot_output_alloc();
2874 if (!new_output) {
2875 ret = LTTNG_ERR_NOMEM;
2876 goto error;
2877 }
2878
2879 ret = snapshot_output_init(output->max_size, output->name,
2880 output->ctrl_url, output->data_url, session->consumer, new_output,
2881 &session->snapshot);
2882 if (ret < 0) {
2883 if (ret == -ENOMEM) {
2884 ret = LTTNG_ERR_NOMEM;
2885 } else {
2886 ret = LTTNG_ERR_INVALID;
2887 }
2888 goto free_error;
2889 }
2890
2891 rcu_read_lock();
2892 snapshot_add_output(&session->snapshot, new_output);
2893 if (id) {
2894 *id = new_output->id;
2895 }
2896 rcu_read_unlock();
2897
2898 return LTTNG_OK;
2899
2900 free_error:
2901 snapshot_output_destroy(new_output);
2902 error:
2903 return ret;
2904 }
2905
2906 /*
2907 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
2908 *
2909 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2910 */
2911 int cmd_snapshot_del_output(struct ltt_session *session,
2912 struct lttng_snapshot_output *output)
2913 {
2914 int ret;
2915 struct snapshot_output *sout = NULL;
2916
2917 assert(session);
2918 assert(output);
2919
2920 rcu_read_lock();
2921
2922 /*
2923 * Permission denied to create an output if the session is not
2924 * set in no output mode.
2925 */
2926 if (session->output_traces) {
2927 ret = LTTNG_ERR_EPERM;
2928 goto error;
2929 }
2930
2931 if (output->id) {
2932 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
2933 session->name);
2934 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
2935 } else if (*output->name != '\0') {
2936 DBG("Cmd snapshot del output name %s for session %s", output->name,
2937 session->name);
2938 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
2939 }
2940 if (!sout) {
2941 ret = LTTNG_ERR_INVALID;
2942 goto error;
2943 }
2944
2945 snapshot_delete_output(&session->snapshot, sout);
2946 snapshot_output_destroy(sout);
2947 ret = LTTNG_OK;
2948
2949 error:
2950 rcu_read_unlock();
2951 return ret;
2952 }
2953
2954 /*
2955 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
2956 *
2957 * If no output is available, outputs is untouched and 0 is returned.
2958 *
2959 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
2960 */
2961 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
2962 struct lttng_snapshot_output **outputs)
2963 {
2964 int ret, idx = 0;
2965 struct lttng_snapshot_output *list = NULL;
2966 struct lttng_ht_iter iter;
2967 struct snapshot_output *output;
2968
2969 assert(session);
2970 assert(outputs);
2971
2972 DBG("Cmd snapshot list outputs for session %s", session->name);
2973
2974 /*
2975 * Permission denied to create an output if the session is not
2976 * set in no output mode.
2977 */
2978 if (session->output_traces) {
2979 ret = -LTTNG_ERR_EPERM;
2980 goto error;
2981 }
2982
2983 if (session->snapshot.nb_output == 0) {
2984 ret = 0;
2985 goto error;
2986 }
2987
2988 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
2989 if (!list) {
2990 ret = -LTTNG_ERR_NOMEM;
2991 goto error;
2992 }
2993
2994 /* Copy list from session to the new list object. */
2995 rcu_read_lock();
2996 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
2997 output, node.node) {
2998 assert(output->consumer);
2999 list[idx].id = output->id;
3000 list[idx].max_size = output->max_size;
3001 strncpy(list[idx].name, output->name, sizeof(list[idx].name));
3002 if (output->consumer->type == CONSUMER_DST_LOCAL) {
3003 strncpy(list[idx].ctrl_url, output->consumer->dst.trace_path,
3004 sizeof(list[idx].ctrl_url));
3005 } else {
3006 /* Control URI. */
3007 ret = uri_to_str_url(&output->consumer->dst.net.control,
3008 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
3009 if (ret < 0) {
3010 ret = -LTTNG_ERR_NOMEM;
3011 goto error;
3012 }
3013
3014 /* Data URI. */
3015 ret = uri_to_str_url(&output->consumer->dst.net.data,
3016 list[idx].data_url, sizeof(list[idx].data_url));
3017 if (ret < 0) {
3018 ret = -LTTNG_ERR_NOMEM;
3019 goto error;
3020 }
3021 }
3022 idx++;
3023 }
3024
3025 *outputs = list;
3026 list = NULL;
3027 ret = session->snapshot.nb_output;
3028 error:
3029 free(list);
3030 rcu_read_unlock();
3031 return ret;
3032 }
3033
3034 /*
3035 * Send relayd sockets from snapshot output to consumer. Ignore request if the
3036 * snapshot output is *not* set with a remote destination.
3037 *
3038 * Return 0 on success or a LTTNG_ERR code.
3039 */
3040 static int set_relayd_for_snapshot(struct consumer_output *consumer,
3041 struct snapshot_output *snap_output, struct ltt_session *session)
3042 {
3043 int ret = LTTNG_OK;
3044 struct lttng_ht_iter iter;
3045 struct consumer_socket *socket;
3046
3047 assert(consumer);
3048 assert(snap_output);
3049 assert(session);
3050
3051 DBG2("Set relayd object from snapshot output");
3052
3053 /* Ignore if snapshot consumer output is not network. */
3054 if (snap_output->consumer->type != CONSUMER_DST_NET) {
3055 goto error;
3056 }
3057
3058 /*
3059 * For each consumer socket, create and send the relayd object of the
3060 * snapshot output.
3061 */
3062 rcu_read_lock();
3063 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
3064 socket, node.node) {
3065 ret = send_consumer_relayd_sockets(0, session->id,
3066 snap_output->consumer, socket,
3067 session->name, session->hostname,
3068 session->live_timer);
3069 if (ret != LTTNG_OK) {
3070 rcu_read_unlock();
3071 goto error;
3072 }
3073 }
3074 rcu_read_unlock();
3075
3076 error:
3077 return ret;
3078 }
3079
3080 /*
3081 * Record a kernel snapshot.
3082 *
3083 * Return LTTNG_OK on success or a LTTNG_ERR code.
3084 */
3085 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
3086 struct snapshot_output *output, struct ltt_session *session,
3087 int wait, uint64_t nb_packets_per_stream)
3088 {
3089 int ret;
3090
3091 assert(ksess);
3092 assert(output);
3093 assert(session);
3094
3095 /* Get the datetime for the snapshot output directory. */
3096 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
3097 sizeof(output->datetime));
3098 if (!ret) {
3099 ret = LTTNG_ERR_INVALID;
3100 goto error;
3101 }
3102
3103 /*
3104 * Copy kernel session sockets so we can communicate with the right
3105 * consumer for the snapshot record command.
3106 */
3107 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
3108 if (ret < 0) {
3109 ret = LTTNG_ERR_NOMEM;
3110 goto error;
3111 }
3112
3113 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
3114 if (ret != LTTNG_OK) {
3115 goto error_snapshot;
3116 }
3117
3118 ret = kernel_snapshot_record(ksess, output, wait, nb_packets_per_stream);
3119 if (ret != LTTNG_OK) {
3120 goto error_snapshot;
3121 }
3122
3123 ret = LTTNG_OK;
3124 goto end;
3125
3126 error_snapshot:
3127 /* Clean up copied sockets so this output can use some other later on. */
3128 consumer_destroy_output_sockets(output->consumer);
3129 error:
3130 end:
3131 return ret;
3132 }
3133
3134 /*
3135 * Record a UST snapshot.
3136 *
3137 * Return 0 on success or a LTTNG_ERR error code.
3138 */
3139 static int record_ust_snapshot(struct ltt_ust_session *usess,
3140 struct snapshot_output *output, struct ltt_session *session,
3141 int wait, uint64_t nb_packets_per_stream)
3142 {
3143 int ret;
3144
3145 assert(usess);
3146 assert(output);
3147 assert(session);
3148
3149 /* Get the datetime for the snapshot output directory. */
3150 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
3151 sizeof(output->datetime));
3152 if (!ret) {
3153 ret = LTTNG_ERR_INVALID;
3154 goto error;
3155 }
3156
3157 /*
3158 * Copy UST session sockets so we can communicate with the right
3159 * consumer for the snapshot record command.
3160 */
3161 ret = consumer_copy_sockets(output->consumer, usess->consumer);
3162 if (ret < 0) {
3163 ret = LTTNG_ERR_NOMEM;
3164 goto error;
3165 }
3166
3167 ret = set_relayd_for_snapshot(usess->consumer, output, session);
3168 if (ret != LTTNG_OK) {
3169 goto error_snapshot;
3170 }
3171
3172 ret = ust_app_snapshot_record(usess, output, wait, nb_packets_per_stream);
3173 if (ret < 0) {
3174 switch (-ret) {
3175 case EINVAL:
3176 ret = LTTNG_ERR_INVALID;
3177 break;
3178 case ENODATA:
3179 ret = LTTNG_ERR_SNAPSHOT_NODATA;
3180 break;
3181 default:
3182 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3183 break;
3184 }
3185 goto error_snapshot;
3186 }
3187
3188 ret = LTTNG_OK;
3189
3190 error_snapshot:
3191 /* Clean up copied sockets so this output can use some other later on. */
3192 consumer_destroy_output_sockets(output->consumer);
3193 error:
3194 return ret;
3195 }
3196
3197 static
3198 uint64_t get_session_size_one_more_packet_per_stream(struct ltt_session *session,
3199 uint64_t cur_nr_packets)
3200 {
3201 uint64_t tot_size = 0;
3202
3203 if (session->kernel_session) {
3204 struct ltt_kernel_channel *chan;
3205 struct ltt_kernel_session *ksess = session->kernel_session;
3206
3207 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
3208 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
3209 /*
3210 * Don't take channel into account if we
3211 * already grab all its packets.
3212 */
3213 continue;
3214 }
3215 tot_size += chan->channel->attr.subbuf_size
3216 * chan->stream_count;
3217 }
3218 }
3219
3220 if (session->ust_session) {
3221 struct ltt_ust_session *usess = session->ust_session;
3222
3223 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
3224 cur_nr_packets);
3225 }
3226
3227 return tot_size;
3228 }
3229
3230 /*
3231 * Calculate the number of packets we can grab from each stream that
3232 * fits within the overall snapshot max size.
3233 *
3234 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
3235 * the number of packets per stream.
3236 *
3237 * TODO: this approach is not perfect: we consider the worse case
3238 * (packet filling the sub-buffers) as an upper bound, but we could do
3239 * better if we do this calculation while we actually grab the packet
3240 * content: we would know how much padding we don't actually store into
3241 * the file.
3242 *
3243 * This algorithm is currently bounded by the number of packets per
3244 * stream.
3245 *
3246 * Since we call this algorithm before actually grabbing the data, it's
3247 * an approximation: for instance, applications could appear/disappear
3248 * in between this call and actually grabbing data.
3249 */
3250 static
3251 int64_t get_session_nb_packets_per_stream(struct ltt_session *session, uint64_t max_size)
3252 {
3253 int64_t size_left;
3254 uint64_t cur_nb_packets = 0;
3255
3256 if (!max_size) {
3257 return 0; /* Infinite */
3258 }
3259
3260 size_left = max_size;
3261 for (;;) {
3262 uint64_t one_more_packet_tot_size;
3263
3264 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(session,
3265 cur_nb_packets);
3266 if (!one_more_packet_tot_size) {
3267 /* We are already grabbing all packets. */
3268 break;
3269 }
3270 size_left -= one_more_packet_tot_size;
3271 if (size_left < 0) {
3272 break;
3273 }
3274 cur_nb_packets++;
3275 }
3276 if (!cur_nb_packets) {
3277 /* Not enough room to grab one packet of each stream, error. */
3278 return -1;
3279 }
3280 return cur_nb_packets;
3281 }
3282
3283 /*
3284 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
3285 *
3286 * The wait parameter is ignored so this call always wait for the snapshot to
3287 * complete before returning.
3288 *
3289 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3290 */
3291 int cmd_snapshot_record(struct ltt_session *session,
3292 struct lttng_snapshot_output *output, int wait)
3293 {
3294 int ret = LTTNG_OK;
3295 unsigned int use_tmp_output = 0;
3296 struct snapshot_output tmp_output;
3297 unsigned int snapshot_success = 0;
3298
3299 assert(session);
3300 assert(output);
3301
3302 DBG("Cmd snapshot record for session %s", session->name);
3303
3304 /*
3305 * Permission denied to create an output if the session is not
3306 * set in no output mode.
3307 */
3308 if (session->output_traces) {
3309 ret = LTTNG_ERR_EPERM;
3310 goto error;
3311 }
3312
3313 /* The session needs to be started at least once. */
3314 if (!session->has_been_started) {
3315 ret = LTTNG_ERR_START_SESSION_ONCE;
3316 goto error;
3317 }
3318
3319 /* Use temporary output for the session. */
3320 if (*output->ctrl_url != '\0') {
3321 ret = snapshot_output_init(output->max_size, output->name,
3322 output->ctrl_url, output->data_url, session->consumer,
3323 &tmp_output, NULL);
3324 if (ret < 0) {
3325 if (ret == -ENOMEM) {
3326 ret = LTTNG_ERR_NOMEM;
3327 } else {
3328 ret = LTTNG_ERR_INVALID;
3329 }
3330 goto error;
3331 }
3332 /* Use the global session count for the temporary snapshot. */
3333 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3334 use_tmp_output = 1;
3335 }
3336
3337 if (session->kernel_session) {
3338 struct ltt_kernel_session *ksess = session->kernel_session;
3339
3340 if (use_tmp_output) {
3341 int64_t nb_packets_per_stream;
3342
3343 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3344 tmp_output.max_size);
3345 if (nb_packets_per_stream < 0) {
3346 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3347 goto error;
3348 }
3349 ret = record_kernel_snapshot(ksess, &tmp_output, session,
3350 wait, nb_packets_per_stream);
3351 if (ret != LTTNG_OK) {
3352 goto error;
3353 }
3354 snapshot_success = 1;
3355 } else {
3356 struct snapshot_output *sout;
3357 struct lttng_ht_iter iter;
3358
3359 rcu_read_lock();
3360 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3361 &iter.iter, sout, node.node) {
3362 int64_t nb_packets_per_stream;
3363
3364 /*
3365 * Make a local copy of the output and assign the possible
3366 * temporary value given by the caller.
3367 */
3368 memset(&tmp_output, 0, sizeof(tmp_output));
3369 memcpy(&tmp_output, sout, sizeof(tmp_output));
3370
3371 if (output->max_size != (uint64_t) -1ULL) {
3372 tmp_output.max_size = output->max_size;
3373 }
3374
3375 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3376 tmp_output.max_size);
3377 if (nb_packets_per_stream < 0) {
3378 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3379 goto error;
3380 }
3381
3382 /* Use temporary name. */
3383 if (*output->name != '\0') {
3384 strncpy(tmp_output.name, output->name,
3385 sizeof(tmp_output.name));
3386 }
3387
3388 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3389
3390 ret = record_kernel_snapshot(ksess, &tmp_output,
3391 session, wait, nb_packets_per_stream);
3392 if (ret != LTTNG_OK) {
3393 rcu_read_unlock();
3394 goto error;
3395 }
3396 snapshot_success = 1;
3397 }
3398 rcu_read_unlock();
3399 }
3400 }
3401
3402 if (session->ust_session) {
3403 struct ltt_ust_session *usess = session->ust_session;
3404
3405 if (use_tmp_output) {
3406 int64_t nb_packets_per_stream;
3407
3408 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3409 tmp_output.max_size);
3410 if (nb_packets_per_stream < 0) {
3411 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3412 goto error;
3413 }
3414 ret = record_ust_snapshot(usess, &tmp_output, session,
3415 wait, nb_packets_per_stream);
3416 if (ret != LTTNG_OK) {
3417 goto error;
3418 }
3419 snapshot_success = 1;
3420 } else {
3421 struct snapshot_output *sout;
3422 struct lttng_ht_iter iter;
3423
3424 rcu_read_lock();
3425 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3426 &iter.iter, sout, node.node) {
3427 int64_t nb_packets_per_stream;
3428
3429 /*
3430 * Make a local copy of the output and assign the possible
3431 * temporary value given by the caller.
3432 */
3433 memset(&tmp_output, 0, sizeof(tmp_output));
3434 memcpy(&tmp_output, sout, sizeof(tmp_output));
3435
3436 if (output->max_size != (uint64_t) -1ULL) {
3437 tmp_output.max_size = output->max_size;
3438 }
3439
3440 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3441 tmp_output.max_size);
3442 if (nb_packets_per_stream < 0) {
3443 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3444 rcu_read_unlock();
3445 goto error;
3446 }
3447
3448 /* Use temporary name. */
3449 if (*output->name != '\0') {
3450 strncpy(tmp_output.name, output->name,
3451 sizeof(tmp_output.name));
3452 }
3453
3454 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3455
3456 ret = record_ust_snapshot(usess, &tmp_output, session,
3457 wait, nb_packets_per_stream);
3458 if (ret != LTTNG_OK) {
3459 rcu_read_unlock();
3460 goto error;
3461 }
3462 snapshot_success = 1;
3463 }
3464 rcu_read_unlock();
3465 }
3466 }
3467
3468 if (snapshot_success) {
3469 session->snapshot.nb_snapshot++;
3470 } else {
3471 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3472 }
3473
3474 error:
3475 return ret;
3476 }
3477
3478 /*
3479 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
3480 */
3481 int cmd_set_session_shm_path(struct ltt_session *session,
3482 const char *shm_path)
3483 {
3484 /* Safety net */
3485 assert(session);
3486
3487 /*
3488 * Can only set shm path before session is started.
3489 */
3490 if (session->has_been_started) {
3491 return LTTNG_ERR_SESSION_STARTED;
3492 }
3493
3494 strncpy(session->shm_path, shm_path,
3495 sizeof(session->shm_path));
3496 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
3497
3498 return 0;
3499 }
3500
3501 /*
3502 * Init command subsystem.
3503 */
3504 void cmd_init(void)
3505 {
3506 /*
3507 * Set network sequence index to 1 for streams to match a relayd
3508 * socket on the consumer side.
3509 */
3510 pthread_mutex_lock(&relayd_net_seq_idx_lock);
3511 relayd_net_seq_idx = 1;
3512 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
3513
3514 DBG("Command subsystem initialized");
3515 }
LTTng 2.0 tools and control repository
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