ffff05809d2f072cd6c40ea00f83dec07fad5f56
[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 #include "agent.h"
42
43 #include "cmd.h"
44
45 /*
46 * Used to keep a unique index for each relayd socket created where this value
47 * is associated with streams on the consumer so it can match the right relayd
48 * to send to. It must be accessed with the relayd_net_seq_idx_lock
49 * held.
50 */
51 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
52 static uint64_t relayd_net_seq_idx;
53
54 static int validate_event_name(const char *);
55 static int validate_ust_event_name(const char *);
56 static int cmd_enable_event_internal(struct ltt_session *session,
57 struct lttng_domain *domain,
58 char *channel_name, struct lttng_event *event,
59 char *filter_expression,
60 struct lttng_filter_bytecode *filter,
61 struct lttng_event_exclusion *exclusion,
62 int wpipe);
63
64 /*
65 * Create a session path used by list_lttng_sessions for the case that the
66 * session consumer is on the network.
67 */
68 static int build_network_session_path(char *dst, size_t size,
69 struct ltt_session *session)
70 {
71 int ret, kdata_port, udata_port;
72 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
73 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
74
75 assert(session);
76 assert(dst);
77
78 memset(tmp_urls, 0, sizeof(tmp_urls));
79 memset(tmp_uurl, 0, sizeof(tmp_uurl));
80
81 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
82
83 if (session->kernel_session && session->kernel_session->consumer) {
84 kuri = &session->kernel_session->consumer->dst.net.control;
85 kdata_port = session->kernel_session->consumer->dst.net.data.port;
86 }
87
88 if (session->ust_session && session->ust_session->consumer) {
89 uuri = &session->ust_session->consumer->dst.net.control;
90 udata_port = session->ust_session->consumer->dst.net.data.port;
91 }
92
93 if (uuri == NULL && kuri == NULL) {
94 uri = &session->consumer->dst.net.control;
95 kdata_port = session->consumer->dst.net.data.port;
96 } else if (kuri && uuri) {
97 ret = uri_compare(kuri, uuri);
98 if (ret) {
99 /* Not Equal */
100 uri = kuri;
101 /* Build uuri URL string */
102 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
103 if (ret < 0) {
104 goto error;
105 }
106 } else {
107 uri = kuri;
108 }
109 } else if (kuri && uuri == NULL) {
110 uri = kuri;
111 } else if (uuri && kuri == NULL) {
112 uri = uuri;
113 }
114
115 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
116 if (ret < 0) {
117 goto error;
118 }
119
120 /*
121 * Do we have a UST url set. If yes, this means we have both kernel and UST
122 * to print.
123 */
124 if (*tmp_uurl != '\0') {
125 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
126 tmp_urls, kdata_port, tmp_uurl, udata_port);
127 } else {
128 int dport;
129 if (kuri || (!kuri && !uuri)) {
130 dport = kdata_port;
131 } else {
132 /* No kernel URI, use the UST port. */
133 dport = udata_port;
134 }
135 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
136 }
137
138 error:
139 return ret;
140 }
141
142 /*
143 * Fill lttng_channel array of all channels.
144 */
145 static void list_lttng_channels(enum lttng_domain_type domain,
146 struct ltt_session *session, struct lttng_channel *channels)
147 {
148 int i = 0;
149 struct ltt_kernel_channel *kchan;
150
151 DBG("Listing channels for session %s", session->name);
152
153 switch (domain) {
154 case LTTNG_DOMAIN_KERNEL:
155 /* Kernel channels */
156 if (session->kernel_session != NULL) {
157 cds_list_for_each_entry(kchan,
158 &session->kernel_session->channel_list.head, list) {
159 /* Copy lttng_channel struct to array */
160 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
161 channels[i].enabled = kchan->enabled;
162 i++;
163 }
164 }
165 break;
166 case LTTNG_DOMAIN_UST:
167 {
168 struct lttng_ht_iter iter;
169 struct ltt_ust_channel *uchan;
170
171 rcu_read_lock();
172 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
173 &iter.iter, uchan, node.node) {
174 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
175 channels[i].attr.overwrite = uchan->attr.overwrite;
176 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
177 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
178 channels[i].attr.switch_timer_interval =
179 uchan->attr.switch_timer_interval;
180 channels[i].attr.read_timer_interval =
181 uchan->attr.read_timer_interval;
182 channels[i].enabled = uchan->enabled;
183 channels[i].attr.tracefile_size = uchan->tracefile_size;
184 channels[i].attr.tracefile_count = uchan->tracefile_count;
185 switch (uchan->attr.output) {
186 case LTTNG_UST_MMAP:
187 default:
188 channels[i].attr.output = LTTNG_EVENT_MMAP;
189 break;
190 }
191 i++;
192 }
193 rcu_read_unlock();
194 break;
195 }
196 default:
197 break;
198 }
199 }
200
201 /*
202 * Create a list of agent domain events.
203 *
204 * Return number of events in list on success or else a negative value.
205 */
206 static int list_lttng_agent_events(struct agent *agt,
207 struct lttng_event **events)
208 {
209 int i = 0, ret = 0;
210 unsigned int nb_event = 0;
211 struct agent_event *event;
212 struct lttng_event *tmp_events;
213 struct lttng_ht_iter iter;
214
215 assert(agt);
216 assert(events);
217
218 DBG3("Listing agent events");
219
220 rcu_read_lock();
221 nb_event = lttng_ht_get_count(agt->events);
222 rcu_read_unlock();
223 if (nb_event == 0) {
224 ret = nb_event;
225 goto error;
226 }
227
228 tmp_events = zmalloc(nb_event * sizeof(*tmp_events));
229 if (!tmp_events) {
230 PERROR("zmalloc agent events session");
231 ret = -LTTNG_ERR_FATAL;
232 goto error;
233 }
234
235 rcu_read_lock();
236 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
237 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
238 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
239 tmp_events[i].enabled = event->enabled;
240 tmp_events[i].loglevel = event->loglevel;
241 tmp_events[i].loglevel_type = event->loglevel_type;
242 i++;
243 }
244 rcu_read_unlock();
245
246 *events = tmp_events;
247 ret = nb_event;
248
249 error:
250 assert(nb_event == i);
251 return ret;
252 }
253
254 /*
255 * Create a list of ust global domain events.
256 */
257 static int list_lttng_ust_global_events(char *channel_name,
258 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
259 {
260 int i = 0, ret = 0;
261 unsigned int nb_event = 0;
262 struct lttng_ht_iter iter;
263 struct lttng_ht_node_str *node;
264 struct ltt_ust_channel *uchan;
265 struct ltt_ust_event *uevent;
266 struct lttng_event *tmp;
267
268 DBG("Listing UST global events for channel %s", channel_name);
269
270 rcu_read_lock();
271
272 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
273 node = lttng_ht_iter_get_node_str(&iter);
274 if (node == NULL) {
275 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
276 goto error;
277 }
278
279 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
280
281 nb_event = lttng_ht_get_count(uchan->events);
282 if (nb_event == 0) {
283 ret = nb_event;
284 goto error;
285 }
286
287 DBG3("Listing UST global %d events", nb_event);
288
289 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
290 if (tmp == NULL) {
291 ret = LTTNG_ERR_FATAL;
292 goto error;
293 }
294
295 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
296 if (uevent->internal) {
297 /* This event should remain hidden from clients */
298 nb_event--;
299 continue;
300 }
301 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
302 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
303 tmp[i].enabled = uevent->enabled;
304
305 switch (uevent->attr.instrumentation) {
306 case LTTNG_UST_TRACEPOINT:
307 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
308 break;
309 case LTTNG_UST_PROBE:
310 tmp[i].type = LTTNG_EVENT_PROBE;
311 break;
312 case LTTNG_UST_FUNCTION:
313 tmp[i].type = LTTNG_EVENT_FUNCTION;
314 break;
315 }
316
317 tmp[i].loglevel = uevent->attr.loglevel;
318 switch (uevent->attr.loglevel_type) {
319 case LTTNG_UST_LOGLEVEL_ALL:
320 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
321 break;
322 case LTTNG_UST_LOGLEVEL_RANGE:
323 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
324 break;
325 case LTTNG_UST_LOGLEVEL_SINGLE:
326 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
327 break;
328 }
329 if (uevent->filter) {
330 tmp[i].filter = 1;
331 }
332 if (uevent->exclusion) {
333 tmp[i].exclusion = 1;
334 }
335 i++;
336 }
337
338 ret = nb_event;
339 *events = tmp;
340
341 error:
342 rcu_read_unlock();
343 return ret;
344 }
345
346 /*
347 * Fill lttng_event array of all kernel events in the channel.
348 */
349 static int list_lttng_kernel_events(char *channel_name,
350 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
351 {
352 int i = 0, ret;
353 unsigned int nb_event;
354 struct ltt_kernel_event *event;
355 struct ltt_kernel_channel *kchan;
356
357 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
358 if (kchan == NULL) {
359 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
360 goto error;
361 }
362
363 nb_event = kchan->event_count;
364
365 DBG("Listing events for channel %s", kchan->channel->name);
366
367 if (nb_event == 0) {
368 *events = NULL;
369 goto syscall;
370 }
371
372 *events = zmalloc(nb_event * sizeof(struct lttng_event));
373 if (*events == NULL) {
374 ret = LTTNG_ERR_FATAL;
375 goto error;
376 }
377
378 /* Kernel channels */
379 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
380 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
381 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
382 (*events)[i].enabled = event->enabled;
383
384 switch (event->event->instrumentation) {
385 case LTTNG_KERNEL_TRACEPOINT:
386 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
387 break;
388 case LTTNG_KERNEL_KRETPROBE:
389 (*events)[i].type = LTTNG_EVENT_FUNCTION;
390 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
391 sizeof(struct lttng_kernel_kprobe));
392 break;
393 case LTTNG_KERNEL_KPROBE:
394 (*events)[i].type = LTTNG_EVENT_PROBE;
395 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
396 sizeof(struct lttng_kernel_kprobe));
397 break;
398 case LTTNG_KERNEL_FUNCTION:
399 (*events)[i].type = LTTNG_EVENT_FUNCTION;
400 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
401 sizeof(struct lttng_kernel_function));
402 break;
403 case LTTNG_KERNEL_NOOP:
404 (*events)[i].type = LTTNG_EVENT_NOOP;
405 break;
406 case LTTNG_KERNEL_SYSCALL:
407 (*events)[i].type = LTTNG_EVENT_SYSCALL;
408 break;
409 case LTTNG_KERNEL_ALL:
410 assert(0);
411 break;
412 }
413 i++;
414 }
415
416 syscall:
417 if (syscall_table) {
418 ssize_t new_size;
419
420 new_size = syscall_list_channel(kchan, events, nb_event);
421 if (new_size < 0) {
422 free(events);
423 ret = -new_size;
424 goto error;
425 }
426 nb_event = new_size;
427 }
428
429 return nb_event;
430
431 error:
432 /* Negate the error code to differentiate the size from an error */
433 return -ret;
434 }
435
436 /*
437 * Add URI so the consumer output object. Set the correct path depending on the
438 * domain adding the default trace directory.
439 */
440 static int add_uri_to_consumer(struct consumer_output *consumer,
441 struct lttng_uri *uri, enum lttng_domain_type domain,
442 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(enum lttng_domain_type domain,
640 unsigned int session_id, struct lttng_uri *relayd_uri,
641 struct consumer_output *consumer,
642 struct consumer_socket *consumer_sock,
643 char *session_name, char *hostname, int session_live_timer)
644 {
645 int ret;
646 struct lttcomm_relayd_sock *rsock = NULL;
647
648 /* Connect to relayd and make version check if uri is the control. */
649 ret = create_connect_relayd(relayd_uri, &rsock);
650 if (ret != LTTNG_OK) {
651 goto error;
652 }
653 assert(rsock);
654
655 /* Set the network sequence index if not set. */
656 if (consumer->net_seq_index == (uint64_t) -1ULL) {
657 pthread_mutex_lock(&relayd_net_seq_idx_lock);
658 /*
659 * Increment net_seq_idx because we are about to transfer the
660 * new relayd socket to the consumer.
661 * Assign unique key so the consumer can match streams.
662 */
663 consumer->net_seq_index = ++relayd_net_seq_idx;
664 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
665 }
666
667 /* Send relayd socket to consumer. */
668 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
669 relayd_uri->stype, session_id,
670 session_name, hostname, session_live_timer);
671 if (ret < 0) {
672 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
673 goto close_sock;
674 }
675
676 /* Flag that the corresponding socket was sent. */
677 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
678 consumer_sock->control_sock_sent = 1;
679 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
680 consumer_sock->data_sock_sent = 1;
681 }
682
683 ret = LTTNG_OK;
684
685 /*
686 * Close socket which was dup on the consumer side. The session daemon does
687 * NOT keep track of the relayd socket(s) once transfer to the consumer.
688 */
689
690 close_sock:
691 (void) relayd_close(rsock);
692 free(rsock);
693
694 error:
695 if (ret != LTTNG_OK) {
696 /*
697 * The consumer output for this session should not be used anymore
698 * since the relayd connection failed thus making any tracing or/and
699 * streaming not usable.
700 */
701 consumer->enabled = 0;
702 }
703 return ret;
704 }
705
706 /*
707 * Send both relayd sockets to a specific consumer and domain. This is a
708 * helper function to facilitate sending the information to the consumer for a
709 * session.
710 */
711 static int send_consumer_relayd_sockets(enum lttng_domain_type domain,
712 unsigned int session_id, struct consumer_output *consumer,
713 struct consumer_socket *sock, char *session_name,
714 char *hostname, int session_live_timer)
715 {
716 int ret = LTTNG_OK;
717
718 assert(consumer);
719 assert(sock);
720
721 /* Sending control relayd socket. */
722 if (!sock->control_sock_sent) {
723 ret = send_consumer_relayd_socket(domain, session_id,
724 &consumer->dst.net.control, consumer, sock,
725 session_name, hostname, session_live_timer);
726 if (ret != LTTNG_OK) {
727 goto error;
728 }
729 }
730
731 /* Sending data relayd socket. */
732 if (!sock->data_sock_sent) {
733 ret = send_consumer_relayd_socket(domain, session_id,
734 &consumer->dst.net.data, consumer, sock,
735 session_name, hostname, session_live_timer);
736 if (ret != LTTNG_OK) {
737 goto error;
738 }
739 }
740
741 error:
742 return ret;
743 }
744
745 /*
746 * Setup relayd connections for a tracing session. First creates the socket to
747 * the relayd and send them to the right domain consumer. Consumer type MUST be
748 * network.
749 */
750 int cmd_setup_relayd(struct ltt_session *session)
751 {
752 int ret = LTTNG_OK;
753 struct ltt_ust_session *usess;
754 struct ltt_kernel_session *ksess;
755 struct consumer_socket *socket;
756 struct lttng_ht_iter iter;
757
758 assert(session);
759
760 usess = session->ust_session;
761 ksess = session->kernel_session;
762
763 DBG("Setting relayd for session %s", session->name);
764
765 rcu_read_lock();
766
767 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
768 && usess->consumer->enabled) {
769 /* For each consumer socket, send relayd sockets */
770 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
771 socket, node.node) {
772 pthread_mutex_lock(socket->lock);
773 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
774 usess->consumer, socket,
775 session->name, session->hostname,
776 session->live_timer);
777 pthread_mutex_unlock(socket->lock);
778 if (ret != LTTNG_OK) {
779 goto error;
780 }
781 /* Session is now ready for network streaming. */
782 session->net_handle = 1;
783 }
784 }
785
786 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
787 && ksess->consumer->enabled) {
788 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
789 socket, node.node) {
790 pthread_mutex_lock(socket->lock);
791 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
792 ksess->consumer, socket,
793 session->name, session->hostname,
794 session->live_timer);
795 pthread_mutex_unlock(socket->lock);
796 if (ret != LTTNG_OK) {
797 goto error;
798 }
799 /* Session is now ready for network streaming. */
800 session->net_handle = 1;
801 }
802 }
803
804 error:
805 rcu_read_unlock();
806 return ret;
807 }
808
809 /*
810 * Start a kernel session by opening all necessary streams.
811 */
812 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
813 {
814 int ret;
815 struct ltt_kernel_channel *kchan;
816
817 /* Open kernel metadata */
818 if (ksess->metadata == NULL && ksess->output_traces) {
819 ret = kernel_open_metadata(ksess);
820 if (ret < 0) {
821 ret = LTTNG_ERR_KERN_META_FAIL;
822 goto error;
823 }
824 }
825
826 /* Open kernel metadata stream */
827 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
828 ret = kernel_open_metadata_stream(ksess);
829 if (ret < 0) {
830 ERR("Kernel create metadata stream failed");
831 ret = LTTNG_ERR_KERN_STREAM_FAIL;
832 goto error;
833 }
834 }
835
836 /* For each channel */
837 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
838 if (kchan->stream_count == 0) {
839 ret = kernel_open_channel_stream(kchan);
840 if (ret < 0) {
841 ret = LTTNG_ERR_KERN_STREAM_FAIL;
842 goto error;
843 }
844 /* Update the stream global counter */
845 ksess->stream_count_global += ret;
846 }
847 }
848
849 /* Setup kernel consumer socket and send fds to it */
850 ret = init_kernel_tracing(ksess);
851 if (ret != 0) {
852 ret = LTTNG_ERR_KERN_START_FAIL;
853 goto error;
854 }
855
856 /* This start the kernel tracing */
857 ret = kernel_start_session(ksess);
858 if (ret < 0) {
859 ret = LTTNG_ERR_KERN_START_FAIL;
860 goto error;
861 }
862
863 /* Quiescent wait after starting trace */
864 kernel_wait_quiescent(kernel_tracer_fd);
865
866 ksess->active = 1;
867
868 ret = LTTNG_OK;
869
870 error:
871 return ret;
872 }
873
874 /*
875 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
876 */
877 int cmd_disable_channel(struct ltt_session *session,
878 enum lttng_domain_type domain, char *channel_name)
879 {
880 int ret;
881 struct ltt_ust_session *usess;
882
883 usess = session->ust_session;
884
885 rcu_read_lock();
886
887 switch (domain) {
888 case LTTNG_DOMAIN_KERNEL:
889 {
890 ret = channel_kernel_disable(session->kernel_session,
891 channel_name);
892 if (ret != LTTNG_OK) {
893 goto error;
894 }
895
896 kernel_wait_quiescent(kernel_tracer_fd);
897 break;
898 }
899 case LTTNG_DOMAIN_UST:
900 {
901 struct ltt_ust_channel *uchan;
902 struct lttng_ht *chan_ht;
903
904 chan_ht = usess->domain_global.channels;
905
906 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
907 if (uchan == NULL) {
908 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
909 goto error;
910 }
911
912 ret = channel_ust_disable(usess, uchan);
913 if (ret != LTTNG_OK) {
914 goto error;
915 }
916 break;
917 }
918 default:
919 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
920 goto error;
921 }
922
923 ret = LTTNG_OK;
924
925 error:
926 rcu_read_unlock();
927 return ret;
928 }
929
930 /*
931 * Command LTTNG_TRACK_PID processed by the client thread.
932 *
933 * Called with session lock held.
934 */
935 int cmd_track_pid(struct ltt_session *session, enum lttng_domain_type domain,
936 int pid)
937 {
938 int ret;
939
940 rcu_read_lock();
941
942 switch (domain) {
943 case LTTNG_DOMAIN_KERNEL:
944 {
945 struct ltt_kernel_session *ksess;
946
947 ksess = session->kernel_session;
948
949 ret = kernel_track_pid(ksess, pid);
950 if (ret != LTTNG_OK) {
951 goto error;
952 }
953
954 kernel_wait_quiescent(kernel_tracer_fd);
955 break;
956 }
957 case LTTNG_DOMAIN_UST:
958 {
959 struct ltt_ust_session *usess;
960
961 usess = session->ust_session;
962
963 ret = trace_ust_track_pid(usess, pid);
964 if (ret != LTTNG_OK) {
965 goto error;
966 }
967 break;
968 }
969 default:
970 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
971 goto error;
972 }
973
974 ret = LTTNG_OK;
975
976 error:
977 rcu_read_unlock();
978 return ret;
979 }
980
981 /*
982 * Command LTTNG_UNTRACK_PID processed by the client thread.
983 *
984 * Called with session lock held.
985 */
986 int cmd_untrack_pid(struct ltt_session *session, enum lttng_domain_type domain,
987 int pid)
988 {
989 int ret;
990
991 rcu_read_lock();
992
993 switch (domain) {
994 case LTTNG_DOMAIN_KERNEL:
995 {
996 struct ltt_kernel_session *ksess;
997
998 ksess = session->kernel_session;
999
1000 ret = kernel_untrack_pid(ksess, pid);
1001 if (ret != LTTNG_OK) {
1002 goto error;
1003 }
1004
1005 kernel_wait_quiescent(kernel_tracer_fd);
1006 break;
1007 }
1008 case LTTNG_DOMAIN_UST:
1009 {
1010 struct ltt_ust_session *usess;
1011
1012 usess = session->ust_session;
1013
1014 ret = trace_ust_untrack_pid(usess, pid);
1015 if (ret != LTTNG_OK) {
1016 goto error;
1017 }
1018 break;
1019 }
1020 default:
1021 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1022 goto error;
1023 }
1024
1025 ret = LTTNG_OK;
1026
1027 error:
1028 rcu_read_unlock();
1029 return ret;
1030 }
1031
1032 /*
1033 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1034 *
1035 * The wpipe arguments is used as a notifier for the kernel thread.
1036 */
1037 int cmd_enable_channel(struct ltt_session *session,
1038 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1039 {
1040 int ret;
1041 struct ltt_ust_session *usess = session->ust_session;
1042 struct lttng_ht *chan_ht;
1043 size_t len;
1044
1045 assert(session);
1046 assert(attr);
1047 assert(domain);
1048
1049 len = strnlen(attr->name, sizeof(attr->name));
1050
1051 /* Validate channel name */
1052 if (attr->name[0] == '.' ||
1053 memchr(attr->name, '/', len) != NULL) {
1054 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1055 goto end;
1056 }
1057
1058 DBG("Enabling channel %s for session %s", attr->name, session->name);
1059
1060 rcu_read_lock();
1061
1062 /*
1063 * Don't try to enable a channel if the session has been started at
1064 * some point in time before. The tracer does not allow it.
1065 */
1066 if (session->has_been_started) {
1067 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1068 goto error;
1069 }
1070
1071 /*
1072 * If the session is a live session, remove the switch timer, the
1073 * live timer does the same thing but sends also synchronisation
1074 * beacons for inactive streams.
1075 */
1076 if (session->live_timer > 0) {
1077 attr->attr.live_timer_interval = session->live_timer;
1078 attr->attr.switch_timer_interval = 0;
1079 }
1080
1081 /*
1082 * The ringbuffer (both in user space and kernel) behave badly in overwrite
1083 * mode and with less than 2 subbuf so block it right away and send back an
1084 * invalid attribute error.
1085 */
1086 if (attr->attr.overwrite && attr->attr.num_subbuf < 2) {
1087 ret = LTTNG_ERR_INVALID;
1088 goto error;
1089 }
1090
1091 switch (domain->type) {
1092 case LTTNG_DOMAIN_KERNEL:
1093 {
1094 struct ltt_kernel_channel *kchan;
1095
1096 kchan = trace_kernel_get_channel_by_name(attr->name,
1097 session->kernel_session);
1098 if (kchan == NULL) {
1099 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1100 if (attr->name[0] != '\0') {
1101 session->kernel_session->has_non_default_channel = 1;
1102 }
1103 } else {
1104 ret = channel_kernel_enable(session->kernel_session, kchan);
1105 }
1106
1107 if (ret != LTTNG_OK) {
1108 goto error;
1109 }
1110
1111 kernel_wait_quiescent(kernel_tracer_fd);
1112 break;
1113 }
1114 case LTTNG_DOMAIN_UST:
1115 {
1116 struct ltt_ust_channel *uchan;
1117
1118 chan_ht = usess->domain_global.channels;
1119
1120 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1121 if (uchan == NULL) {
1122 ret = channel_ust_create(usess, attr, domain->buf_type);
1123 if (attr->name[0] != '\0') {
1124 usess->has_non_default_channel = 1;
1125 }
1126 } else {
1127 ret = channel_ust_enable(usess, uchan);
1128 }
1129 break;
1130 }
1131 default:
1132 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1133 goto error;
1134 }
1135
1136 error:
1137 rcu_read_unlock();
1138 end:
1139 return ret;
1140 }
1141
1142 /*
1143 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1144 */
1145 int cmd_disable_event(struct ltt_session *session,
1146 enum lttng_domain_type domain, char *channel_name,
1147 struct lttng_event *event)
1148 {
1149 int ret;
1150 char *event_name;
1151
1152 DBG("Disable event command for event \'%s\'", event->name);
1153
1154 event_name = event->name;
1155 if (validate_event_name(event_name)) {
1156 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1157 goto error;
1158 }
1159
1160 /* Error out on unhandled search criteria */
1161 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1162 || event->pid || event->filter || event->exclusion) {
1163 ret = LTTNG_ERR_UNK;
1164 goto error;
1165 }
1166
1167 rcu_read_lock();
1168
1169 switch (domain) {
1170 case LTTNG_DOMAIN_KERNEL:
1171 {
1172 struct ltt_kernel_channel *kchan;
1173 struct ltt_kernel_session *ksess;
1174
1175 ksess = session->kernel_session;
1176
1177 /*
1178 * If a non-default channel has been created in the
1179 * session, explicitely require that -c chan_name needs
1180 * to be provided.
1181 */
1182 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1183 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1184 goto error_unlock;
1185 }
1186
1187 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1188 if (kchan == NULL) {
1189 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1190 goto error_unlock;
1191 }
1192
1193 switch (event->type) {
1194 case LTTNG_EVENT_ALL:
1195 ret = event_kernel_disable_event_all(kchan);
1196 if (ret != LTTNG_OK) {
1197 goto error_unlock;
1198 }
1199 break;
1200 case LTTNG_EVENT_TRACEPOINT: /* fall-through */
1201 case LTTNG_EVENT_SYSCALL:
1202 if (!strcmp(event_name, "*")) {
1203 ret = event_kernel_disable_event_type(kchan,
1204 event->type);
1205 } else {
1206 ret = event_kernel_disable_event(kchan,
1207 event_name);
1208 }
1209 if (ret != LTTNG_OK) {
1210 goto error_unlock;
1211 }
1212 break;
1213 case LTTNG_EVENT_PROBE:
1214 case LTTNG_EVENT_FUNCTION:
1215 case LTTNG_EVENT_FUNCTION_ENTRY:
1216 ret = event_kernel_disable_event(kchan, event_name);
1217 if (ret != LTTNG_OK) {
1218 goto error_unlock;
1219 }
1220 break;
1221 default:
1222 ret = LTTNG_ERR_UNK;
1223 goto error_unlock;
1224 }
1225
1226 kernel_wait_quiescent(kernel_tracer_fd);
1227 break;
1228 }
1229 case LTTNG_DOMAIN_UST:
1230 {
1231 struct ltt_ust_channel *uchan;
1232 struct ltt_ust_session *usess;
1233
1234 usess = session->ust_session;
1235
1236 if (validate_ust_event_name(event_name)) {
1237 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1238 goto error_unlock;
1239 }
1240
1241 /*
1242 * If a non-default channel has been created in the
1243 * session, explicitely require that -c chan_name needs
1244 * to be provided.
1245 */
1246 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1247 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1248 goto error_unlock;
1249 }
1250
1251 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1252 channel_name);
1253 if (uchan == NULL) {
1254 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1255 goto error_unlock;
1256 }
1257
1258 switch (event->type) {
1259 case LTTNG_EVENT_ALL:
1260 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
1261 if (ret != LTTNG_OK) {
1262 goto error_unlock;
1263 }
1264 break;
1265 default:
1266 ret = LTTNG_ERR_UNK;
1267 goto error_unlock;
1268 }
1269
1270 DBG3("Disable UST event %s in channel %s completed", event_name,
1271 channel_name);
1272 break;
1273 }
1274 case LTTNG_DOMAIN_LOG4J:
1275 case LTTNG_DOMAIN_JUL:
1276 case LTTNG_DOMAIN_PYTHON:
1277 {
1278 struct agent *agt;
1279 struct ltt_ust_session *usess = session->ust_session;
1280
1281 assert(usess);
1282
1283 switch (event->type) {
1284 case LTTNG_EVENT_ALL:
1285 break;
1286 default:
1287 ret = LTTNG_ERR_UNK;
1288 goto error_unlock;
1289 }
1290
1291 agt = trace_ust_find_agent(usess, domain);
1292 if (!agt) {
1293 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1294 goto error_unlock;
1295 }
1296 /* The wild card * means that everything should be disabled. */
1297 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1298 ret = event_agent_disable_all(usess, agt);
1299 } else {
1300 ret = event_agent_disable(usess, agt, event_name);
1301 }
1302 if (ret != LTTNG_OK) {
1303 goto error_unlock;
1304 }
1305
1306 break;
1307 }
1308 default:
1309 ret = LTTNG_ERR_UND;
1310 goto error_unlock;
1311 }
1312
1313 ret = LTTNG_OK;
1314
1315 error_unlock:
1316 rcu_read_unlock();
1317 error:
1318 return ret;
1319 }
1320
1321 /*
1322 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1323 */
1324 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1325 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1326 {
1327 int ret, chan_kern_created = 0, chan_ust_created = 0;
1328
1329 switch (domain) {
1330 case LTTNG_DOMAIN_KERNEL:
1331 assert(session->kernel_session);
1332
1333 if (session->kernel_session->channel_count == 0) {
1334 /* Create default channel */
1335 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1336 if (ret != LTTNG_OK) {
1337 goto error;
1338 }
1339 chan_kern_created = 1;
1340 }
1341 /* Add kernel context to kernel tracer */
1342 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1343 if (ret != LTTNG_OK) {
1344 goto error;
1345 }
1346 break;
1347 case LTTNG_DOMAIN_UST:
1348 {
1349 struct ltt_ust_session *usess = session->ust_session;
1350 unsigned int chan_count;
1351
1352 assert(usess);
1353
1354 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1355 if (chan_count == 0) {
1356 struct lttng_channel *attr;
1357 /* Create default channel */
1358 attr = channel_new_default_attr(domain, usess->buffer_type);
1359 if (attr == NULL) {
1360 ret = LTTNG_ERR_FATAL;
1361 goto error;
1362 }
1363
1364 ret = channel_ust_create(usess, attr, usess->buffer_type);
1365 if (ret != LTTNG_OK) {
1366 free(attr);
1367 goto error;
1368 }
1369 free(attr);
1370 chan_ust_created = 1;
1371 }
1372
1373 ret = context_ust_add(usess, domain, ctx, channel_name);
1374 if (ret != LTTNG_OK) {
1375 goto error;
1376 }
1377 break;
1378 }
1379 default:
1380 ret = LTTNG_ERR_UND;
1381 goto error;
1382 }
1383
1384 return LTTNG_OK;
1385
1386 error:
1387 if (chan_kern_created) {
1388 struct ltt_kernel_channel *kchan =
1389 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1390 session->kernel_session);
1391 /* Created previously, this should NOT fail. */
1392 assert(kchan);
1393 kernel_destroy_channel(kchan);
1394 }
1395
1396 if (chan_ust_created) {
1397 struct ltt_ust_channel *uchan =
1398 trace_ust_find_channel_by_name(
1399 session->ust_session->domain_global.channels,
1400 DEFAULT_CHANNEL_NAME);
1401 /* Created previously, this should NOT fail. */
1402 assert(uchan);
1403 /* Remove from the channel list of the session. */
1404 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1405 uchan);
1406 trace_ust_destroy_channel(uchan);
1407 }
1408 return ret;
1409 }
1410
1411 static int validate_event_name(const char *name)
1412 {
1413 int ret = 0;
1414 const char *c = name;
1415 const char *event_name_end = c + LTTNG_SYMBOL_NAME_LEN;
1416 bool null_terminated = false;
1417
1418 /*
1419 * Make sure that unescaped wildcards are only used as the last
1420 * character of the event name.
1421 */
1422 while (c < event_name_end) {
1423 switch (*c) {
1424 case '\0':
1425 null_terminated = true;
1426 goto end;
1427 case '\\':
1428 c++;
1429 break;
1430 case '*':
1431 if ((c + 1) < event_name_end && *(c + 1)) {
1432 /* Wildcard is not the last character */
1433 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1434 goto end;
1435 }
1436 default:
1437 break;
1438 }
1439 c++;
1440 }
1441 end:
1442 if (!ret && !null_terminated) {
1443 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1444 }
1445 return ret;
1446 }
1447
1448 static inline bool name_starts_with(const char *name, const char *prefix)
1449 {
1450 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1451
1452 return !strncmp(name, prefix, max_cmp_len);
1453 }
1454
1455 /* Perform userspace-specific event name validation */
1456 static int validate_ust_event_name(const char *name)
1457 {
1458 int ret = 0;
1459
1460 if (!name) {
1461 ret = -1;
1462 goto end;
1463 }
1464
1465 /*
1466 * Check name against all internal UST event component namespaces used
1467 * by the agents.
1468 */
1469 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1470 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1471 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1472 ret = -1;
1473 }
1474
1475 end:
1476 return ret;
1477 }
1478
1479 /*
1480 * Internal version of cmd_enable_event() with a supplemental
1481 * "internal_event" flag which is used to enable internal events which should
1482 * be hidden from clients. Such events are used in the agent implementation to
1483 * enable the events through which all "agent" events are funeled.
1484 */
1485 static int _cmd_enable_event(struct ltt_session *session,
1486 struct lttng_domain *domain,
1487 char *channel_name, struct lttng_event *event,
1488 char *filter_expression,
1489 struct lttng_filter_bytecode *filter,
1490 struct lttng_event_exclusion *exclusion,
1491 int wpipe, bool internal_event)
1492 {
1493 int ret, channel_created = 0;
1494 struct lttng_channel *attr;
1495
1496 assert(session);
1497 assert(event);
1498 assert(channel_name);
1499
1500 DBG("Enable event command for event \'%s\'", event->name);
1501
1502 ret = validate_event_name(event->name);
1503 if (ret) {
1504 goto error;
1505 }
1506
1507 rcu_read_lock();
1508
1509 switch (domain->type) {
1510 case LTTNG_DOMAIN_KERNEL:
1511 {
1512 struct ltt_kernel_channel *kchan;
1513
1514 /*
1515 * If a non-default channel has been created in the
1516 * session, explicitely require that -c chan_name needs
1517 * to be provided.
1518 */
1519 if (session->kernel_session->has_non_default_channel
1520 && channel_name[0] == '\0') {
1521 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1522 goto error;
1523 }
1524
1525 kchan = trace_kernel_get_channel_by_name(channel_name,
1526 session->kernel_session);
1527 if (kchan == NULL) {
1528 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1529 LTTNG_BUFFER_GLOBAL);
1530 if (attr == NULL) {
1531 ret = LTTNG_ERR_FATAL;
1532 goto error;
1533 }
1534 strncpy(attr->name, channel_name, sizeof(attr->name));
1535
1536 ret = cmd_enable_channel(session, domain, attr, wpipe);
1537 if (ret != LTTNG_OK) {
1538 free(attr);
1539 goto error;
1540 }
1541 free(attr);
1542
1543 channel_created = 1;
1544 }
1545
1546 /* Get the newly created kernel channel pointer */
1547 kchan = trace_kernel_get_channel_by_name(channel_name,
1548 session->kernel_session);
1549 if (kchan == NULL) {
1550 /* This sould not happen... */
1551 ret = LTTNG_ERR_FATAL;
1552 goto error;
1553 }
1554
1555 switch (event->type) {
1556 case LTTNG_EVENT_ALL:
1557 {
1558 char *filter_expression_a = NULL;
1559 struct lttng_filter_bytecode *filter_a = NULL;
1560
1561 /*
1562 * We need to duplicate filter_expression and filter,
1563 * because ownership is passed to first enable
1564 * event.
1565 */
1566 if (filter_expression) {
1567 filter_expression_a = strdup(filter_expression);
1568 if (!filter_expression_a) {
1569 ret = LTTNG_ERR_FATAL;
1570 goto error;
1571 }
1572 }
1573 if (filter) {
1574 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
1575 if (!filter_a) {
1576 free(filter_expression_a);
1577 ret = LTTNG_ERR_FATAL;
1578 goto error;
1579 }
1580 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
1581 }
1582 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
1583 ret = event_kernel_enable_event(kchan, event,
1584 filter_expression, filter);
1585 /* We have passed ownership */
1586 filter_expression = NULL;
1587 filter = NULL;
1588 if (ret != LTTNG_OK) {
1589 if (channel_created) {
1590 /* Let's not leak a useless channel. */
1591 kernel_destroy_channel(kchan);
1592 }
1593 free(filter_expression_a);
1594 free(filter_a);
1595 goto error;
1596 }
1597 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
1598 ret = event_kernel_enable_event(kchan, event,
1599 filter_expression_a, filter_a);
1600 if (ret != LTTNG_OK) {
1601 free(filter_expression_a);
1602 free(filter_a);
1603 goto error;
1604 }
1605 break;
1606 }
1607 case LTTNG_EVENT_PROBE:
1608 case LTTNG_EVENT_FUNCTION:
1609 case LTTNG_EVENT_FUNCTION_ENTRY:
1610 case LTTNG_EVENT_TRACEPOINT:
1611 ret = event_kernel_enable_event(kchan, event,
1612 filter_expression, filter);
1613 /* We have passed ownership */
1614 filter_expression = NULL;
1615 filter = NULL;
1616 if (ret != LTTNG_OK) {
1617 if (channel_created) {
1618 /* Let's not leak a useless channel. */
1619 kernel_destroy_channel(kchan);
1620 }
1621 goto error;
1622 }
1623 break;
1624 case LTTNG_EVENT_SYSCALL:
1625 ret = event_kernel_enable_event(kchan, event,
1626 filter_expression, filter);
1627 /* We have passed ownership */
1628 filter_expression = NULL;
1629 filter = NULL;
1630 if (ret != LTTNG_OK) {
1631 goto error;
1632 }
1633 break;
1634 default:
1635 ret = LTTNG_ERR_UNK;
1636 goto error;
1637 }
1638
1639 kernel_wait_quiescent(kernel_tracer_fd);
1640 break;
1641 }
1642 case LTTNG_DOMAIN_UST:
1643 {
1644 struct ltt_ust_channel *uchan;
1645 struct ltt_ust_session *usess = session->ust_session;
1646
1647 assert(usess);
1648
1649 /*
1650 * If a non-default channel has been created in the
1651 * session, explicitely require that -c chan_name needs
1652 * to be provided.
1653 */
1654 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1655 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1656 goto error;
1657 }
1658
1659 /* Get channel from global UST domain */
1660 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1661 channel_name);
1662 if (uchan == NULL) {
1663 /* Create default channel */
1664 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1665 usess->buffer_type);
1666 if (attr == NULL) {
1667 ret = LTTNG_ERR_FATAL;
1668 goto error;
1669 }
1670 strncpy(attr->name, channel_name, sizeof(attr->name));
1671
1672 ret = cmd_enable_channel(session, domain, attr, wpipe);
1673 if (ret != LTTNG_OK) {
1674 free(attr);
1675 goto error;
1676 }
1677 free(attr);
1678
1679 /* Get the newly created channel reference back */
1680 uchan = trace_ust_find_channel_by_name(
1681 usess->domain_global.channels, channel_name);
1682 assert(uchan);
1683 }
1684
1685 if (!internal_event) {
1686 /*
1687 * Ensure the event name is not reserved for internal
1688 * use.
1689 */
1690 ret = validate_ust_event_name(event->name);
1691 if (ret) {
1692 WARN("Userspace event name %s failed validation.",
1693 event->name ?
1694 event->name : "NULL");
1695 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1696 goto error;
1697 }
1698 }
1699
1700 /* At this point, the session and channel exist on the tracer */
1701 ret = event_ust_enable_tracepoint(usess, uchan, event,
1702 filter_expression, filter, exclusion,
1703 internal_event);
1704 /* We have passed ownership */
1705 filter_expression = NULL;
1706 filter = NULL;
1707 exclusion = NULL;
1708 if (ret != LTTNG_OK) {
1709 goto error;
1710 }
1711 break;
1712 }
1713 case LTTNG_DOMAIN_LOG4J:
1714 case LTTNG_DOMAIN_JUL:
1715 case LTTNG_DOMAIN_PYTHON:
1716 {
1717 const char *default_event_name, *default_chan_name;
1718 struct agent *agt;
1719 struct lttng_event uevent;
1720 struct lttng_domain tmp_dom;
1721 struct ltt_ust_session *usess = session->ust_session;
1722
1723 assert(usess);
1724
1725 agt = trace_ust_find_agent(usess, domain->type);
1726 if (!agt) {
1727 agt = agent_create(domain->type);
1728 if (!agt) {
1729 ret = -LTTNG_ERR_NOMEM;
1730 goto error;
1731 }
1732 agent_add(agt, usess->agents);
1733 }
1734
1735 /* Create the default tracepoint. */
1736 memset(&uevent, 0, sizeof(uevent));
1737 uevent.type = LTTNG_EVENT_TRACEPOINT;
1738 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
1739 default_event_name = event_get_default_agent_ust_name(domain->type);
1740 if (!default_event_name) {
1741 ret = -LTTNG_ERR_FATAL;
1742 goto error;
1743 }
1744 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
1745 uevent.name[sizeof(uevent.name) - 1] = '\0';
1746
1747 /*
1748 * The domain type is changed because we are about to enable the
1749 * default channel and event for the JUL domain that are hardcoded.
1750 * This happens in the UST domain.
1751 */
1752 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
1753 tmp_dom.type = LTTNG_DOMAIN_UST;
1754
1755 switch (domain->type) {
1756 case LTTNG_DOMAIN_LOG4J:
1757 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
1758 break;
1759 case LTTNG_DOMAIN_JUL:
1760 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
1761 break;
1762 case LTTNG_DOMAIN_PYTHON:
1763 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
1764 break;
1765 default:
1766 /* The switch/case we are in makes this impossible */
1767 assert(0);
1768 }
1769
1770 {
1771 struct lttng_filter_bytecode *filter_copy = NULL;
1772
1773 if (filter) {
1774 filter_copy = zmalloc(
1775 sizeof(struct lttng_filter_bytecode)
1776 + filter->len);
1777 if (!filter_copy) {
1778 goto error;
1779 }
1780
1781 memcpy(filter_copy, filter,
1782 sizeof(struct lttng_filter_bytecode)
1783 + filter->len);
1784 }
1785
1786 ret = cmd_enable_event_internal(session, &tmp_dom,
1787 (char *) default_chan_name,
1788 &uevent, filter_expression, filter_copy,
1789 NULL, wpipe);
1790 /* We have passed ownership */
1791 filter_expression = NULL;
1792 }
1793
1794 if (ret != LTTNG_OK && ret != LTTNG_ERR_UST_EVENT_ENABLED) {
1795 goto error;
1796 }
1797
1798 /* The wild card * means that everything should be enabled. */
1799 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1800 ret = event_agent_enable_all(usess, agt, event, filter);
1801 filter = NULL;
1802 } else {
1803 ret = event_agent_enable(usess, agt, event, filter);
1804 filter = NULL;
1805 }
1806 if (ret != LTTNG_OK) {
1807 goto error;
1808 }
1809
1810 break;
1811 }
1812 default:
1813 ret = LTTNG_ERR_UND;
1814 goto error;
1815 }
1816
1817 ret = LTTNG_OK;
1818
1819 error:
1820 free(filter_expression);
1821 free(filter);
1822 free(exclusion);
1823 rcu_read_unlock();
1824 return ret;
1825 }
1826
1827 /*
1828 * Command LTTNG_ENABLE_EVENT processed by the client thread.
1829 * We own filter, exclusion, and filter_expression.
1830 */
1831 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1832 char *channel_name, struct lttng_event *event,
1833 char *filter_expression,
1834 struct lttng_filter_bytecode *filter,
1835 struct lttng_event_exclusion *exclusion,
1836 int wpipe)
1837 {
1838 return _cmd_enable_event(session, domain, channel_name, event,
1839 filter_expression, filter, exclusion, wpipe, false);
1840 }
1841
1842 /*
1843 * Enable an event which is internal to LTTng. An internal should
1844 * never be made visible to clients and are immune to checks such as
1845 * reserved names.
1846 */
1847 static int cmd_enable_event_internal(struct ltt_session *session,
1848 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, true);
1857 }
1858
1859 /*
1860 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1861 */
1862 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
1863 struct lttng_event **events)
1864 {
1865 int ret;
1866 ssize_t nb_events = 0;
1867
1868 switch (domain) {
1869 case LTTNG_DOMAIN_KERNEL:
1870 nb_events = kernel_list_events(kernel_tracer_fd, events);
1871 if (nb_events < 0) {
1872 ret = LTTNG_ERR_KERN_LIST_FAIL;
1873 goto error;
1874 }
1875 break;
1876 case LTTNG_DOMAIN_UST:
1877 nb_events = ust_app_list_events(events);
1878 if (nb_events < 0) {
1879 ret = LTTNG_ERR_UST_LIST_FAIL;
1880 goto error;
1881 }
1882 break;
1883 case LTTNG_DOMAIN_LOG4J:
1884 case LTTNG_DOMAIN_JUL:
1885 case LTTNG_DOMAIN_PYTHON:
1886 nb_events = agent_list_events(events, domain);
1887 if (nb_events < 0) {
1888 ret = LTTNG_ERR_UST_LIST_FAIL;
1889 goto error;
1890 }
1891 break;
1892 default:
1893 ret = LTTNG_ERR_UND;
1894 goto error;
1895 }
1896
1897 return nb_events;
1898
1899 error:
1900 /* Return negative value to differentiate return code */
1901 return -ret;
1902 }
1903
1904 /*
1905 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1906 */
1907 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
1908 struct lttng_event_field **fields)
1909 {
1910 int ret;
1911 ssize_t nb_fields = 0;
1912
1913 switch (domain) {
1914 case LTTNG_DOMAIN_UST:
1915 nb_fields = ust_app_list_event_fields(fields);
1916 if (nb_fields < 0) {
1917 ret = LTTNG_ERR_UST_LIST_FAIL;
1918 goto error;
1919 }
1920 break;
1921 case LTTNG_DOMAIN_KERNEL:
1922 default: /* fall-through */
1923 ret = LTTNG_ERR_UND;
1924 goto error;
1925 }
1926
1927 return nb_fields;
1928
1929 error:
1930 /* Return negative value to differentiate return code */
1931 return -ret;
1932 }
1933
1934 ssize_t cmd_list_syscalls(struct lttng_event **events)
1935 {
1936 return syscall_table_list(events);
1937 }
1938
1939 /*
1940 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
1941 *
1942 * Called with session lock held.
1943 */
1944 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
1945 enum lttng_domain_type domain, int32_t **pids)
1946 {
1947 int ret;
1948 ssize_t nr_pids = 0;
1949
1950 switch (domain) {
1951 case LTTNG_DOMAIN_KERNEL:
1952 {
1953 struct ltt_kernel_session *ksess;
1954
1955 ksess = session->kernel_session;
1956 nr_pids = kernel_list_tracker_pids(ksess, pids);
1957 if (nr_pids < 0) {
1958 ret = LTTNG_ERR_KERN_LIST_FAIL;
1959 goto error;
1960 }
1961 break;
1962 }
1963 case LTTNG_DOMAIN_UST:
1964 {
1965 struct ltt_ust_session *usess;
1966
1967 usess = session->ust_session;
1968 nr_pids = trace_ust_list_tracker_pids(usess, pids);
1969 if (nr_pids < 0) {
1970 ret = LTTNG_ERR_UST_LIST_FAIL;
1971 goto error;
1972 }
1973 break;
1974 }
1975 case LTTNG_DOMAIN_LOG4J:
1976 case LTTNG_DOMAIN_JUL:
1977 case LTTNG_DOMAIN_PYTHON:
1978 default:
1979 ret = LTTNG_ERR_UND;
1980 goto error;
1981 }
1982
1983 return nr_pids;
1984
1985 error:
1986 /* Return negative value to differentiate return code */
1987 return -ret;
1988 }
1989
1990 /*
1991 * Command LTTNG_START_TRACE processed by the client thread.
1992 *
1993 * Called with session mutex held.
1994 */
1995 int cmd_start_trace(struct ltt_session *session)
1996 {
1997 int ret;
1998 unsigned long nb_chan = 0;
1999 struct ltt_kernel_session *ksession;
2000 struct ltt_ust_session *usess;
2001
2002 assert(session);
2003
2004 /* Ease our life a bit ;) */
2005 ksession = session->kernel_session;
2006 usess = session->ust_session;
2007
2008 /* Is the session already started? */
2009 if (session->active) {
2010 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2011 goto error;
2012 }
2013
2014 /*
2015 * Starting a session without channel is useless since after that it's not
2016 * possible to enable channel thus inform the client.
2017 */
2018 if (usess && usess->domain_global.channels) {
2019 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2020 }
2021 if (ksession) {
2022 nb_chan += ksession->channel_count;
2023 }
2024 if (!nb_chan) {
2025 ret = LTTNG_ERR_NO_CHANNEL;
2026 goto error;
2027 }
2028
2029 /* Kernel tracing */
2030 if (ksession != NULL) {
2031 ret = start_kernel_session(ksession, kernel_tracer_fd);
2032 if (ret != LTTNG_OK) {
2033 goto error;
2034 }
2035 }
2036
2037 /* Flag session that trace should start automatically */
2038 if (usess) {
2039 /*
2040 * Even though the start trace might fail, flag this session active so
2041 * other application coming in are started by default.
2042 */
2043 usess->active = 1;
2044
2045 ret = ust_app_start_trace_all(usess);
2046 if (ret < 0) {
2047 ret = LTTNG_ERR_UST_START_FAIL;
2048 goto error;
2049 }
2050 }
2051
2052 /* Flag this after a successful start. */
2053 session->has_been_started = 1;
2054 session->active = 1;
2055
2056 ret = LTTNG_OK;
2057
2058 error:
2059 return ret;
2060 }
2061
2062 /*
2063 * Command LTTNG_STOP_TRACE processed by the client thread.
2064 */
2065 int cmd_stop_trace(struct ltt_session *session)
2066 {
2067 int ret;
2068 struct ltt_kernel_channel *kchan;
2069 struct ltt_kernel_session *ksession;
2070 struct ltt_ust_session *usess;
2071
2072 assert(session);
2073
2074 /* Short cut */
2075 ksession = session->kernel_session;
2076 usess = session->ust_session;
2077
2078 /* Session is not active. Skip everythong and inform the client. */
2079 if (!session->active) {
2080 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2081 goto error;
2082 }
2083
2084 /* Kernel tracer */
2085 if (ksession && ksession->active) {
2086 DBG("Stop kernel tracing");
2087
2088 /* Flush metadata if exist */
2089 if (ksession->metadata_stream_fd >= 0) {
2090 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2091 if (ret < 0) {
2092 ERR("Kernel metadata flush failed");
2093 }
2094 }
2095
2096 /* Flush all buffers before stopping */
2097 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2098 ret = kernel_flush_buffer(kchan);
2099 if (ret < 0) {
2100 ERR("Kernel flush buffer error");
2101 }
2102 }
2103
2104 ret = kernel_stop_session(ksession);
2105 if (ret < 0) {
2106 ret = LTTNG_ERR_KERN_STOP_FAIL;
2107 goto error;
2108 }
2109
2110 kernel_wait_quiescent(kernel_tracer_fd);
2111
2112 ksession->active = 0;
2113 }
2114
2115 if (usess && usess->active) {
2116 /*
2117 * Even though the stop trace might fail, flag this session inactive so
2118 * other application coming in are not started by default.
2119 */
2120 usess->active = 0;
2121
2122 ret = ust_app_stop_trace_all(usess);
2123 if (ret < 0) {
2124 ret = LTTNG_ERR_UST_STOP_FAIL;
2125 goto error;
2126 }
2127 }
2128
2129 /* Flag inactive after a successful stop. */
2130 session->active = 0;
2131 ret = LTTNG_OK;
2132
2133 error:
2134 return ret;
2135 }
2136
2137 /*
2138 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2139 */
2140 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2141 struct lttng_uri *uris)
2142 {
2143 int ret, i;
2144 struct ltt_kernel_session *ksess = session->kernel_session;
2145 struct ltt_ust_session *usess = session->ust_session;
2146
2147 assert(session);
2148 assert(uris);
2149 assert(nb_uri > 0);
2150
2151 /* Can't set consumer URI if the session is active. */
2152 if (session->active) {
2153 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2154 goto error;
2155 }
2156
2157 /* Set the "global" consumer URIs */
2158 for (i = 0; i < nb_uri; i++) {
2159 ret = add_uri_to_consumer(session->consumer,
2160 &uris[i], 0, session->name);
2161 if (ret != LTTNG_OK) {
2162 goto error;
2163 }
2164 }
2165
2166 /* Set UST session URIs */
2167 if (session->ust_session) {
2168 for (i = 0; i < nb_uri; i++) {
2169 ret = add_uri_to_consumer(
2170 session->ust_session->consumer,
2171 &uris[i], LTTNG_DOMAIN_UST,
2172 session->name);
2173 if (ret != LTTNG_OK) {
2174 goto error;
2175 }
2176 }
2177 }
2178
2179 /* Set kernel session URIs */
2180 if (session->kernel_session) {
2181 for (i = 0; i < nb_uri; i++) {
2182 ret = add_uri_to_consumer(
2183 session->kernel_session->consumer,
2184 &uris[i], LTTNG_DOMAIN_KERNEL,
2185 session->name);
2186 if (ret != LTTNG_OK) {
2187 goto error;
2188 }
2189 }
2190 }
2191
2192 /*
2193 * Make sure to set the session in output mode after we set URI since a
2194 * session can be created without URL (thus flagged in no output mode).
2195 */
2196 session->output_traces = 1;
2197 if (ksess) {
2198 ksess->output_traces = 1;
2199 }
2200
2201 if (usess) {
2202 usess->output_traces = 1;
2203 }
2204
2205 /* All good! */
2206 ret = LTTNG_OK;
2207
2208 error:
2209 return ret;
2210 }
2211
2212 /*
2213 * Command LTTNG_CREATE_SESSION processed by the client thread.
2214 */
2215 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
2216 size_t nb_uri, lttng_sock_cred *creds, unsigned int live_timer)
2217 {
2218 int ret;
2219 struct ltt_session *session;
2220
2221 assert(name);
2222 assert(creds);
2223
2224 /*
2225 * Verify if the session already exist
2226 *
2227 * XXX: There is no need for the session lock list here since the caller
2228 * (process_client_msg) is holding it. We might want to change that so a
2229 * single command does not lock the entire session list.
2230 */
2231 session = session_find_by_name(name);
2232 if (session != NULL) {
2233 ret = LTTNG_ERR_EXIST_SESS;
2234 goto find_error;
2235 }
2236
2237 /* Create tracing session in the registry */
2238 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
2239 LTTNG_SOCK_GET_GID_CRED(creds));
2240 if (ret != LTTNG_OK) {
2241 goto session_error;
2242 }
2243
2244 /*
2245 * Get the newly created session pointer back
2246 *
2247 * XXX: There is no need for the session lock list here since the caller
2248 * (process_client_msg) is holding it. We might want to change that so a
2249 * single command does not lock the entire session list.
2250 */
2251 session = session_find_by_name(name);
2252 assert(session);
2253
2254 session->live_timer = live_timer;
2255 /* Create default consumer output for the session not yet created. */
2256 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
2257 if (session->consumer == NULL) {
2258 ret = LTTNG_ERR_FATAL;
2259 goto consumer_error;
2260 }
2261
2262 if (uris) {
2263 ret = cmd_set_consumer_uri(session, nb_uri, uris);
2264 if (ret != LTTNG_OK) {
2265 goto consumer_error;
2266 }
2267 session->output_traces = 1;
2268 } else {
2269 session->output_traces = 0;
2270 DBG2("Session %s created with no output", session->name);
2271 }
2272
2273 session->consumer->enabled = 1;
2274
2275 return LTTNG_OK;
2276
2277 consumer_error:
2278 session_destroy(session);
2279 session_error:
2280 find_error:
2281 return ret;
2282 }
2283
2284 /*
2285 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
2286 */
2287 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
2288 size_t nb_uri, lttng_sock_cred *creds)
2289 {
2290 int ret;
2291 struct ltt_session *session;
2292 struct snapshot_output *new_output = NULL;
2293
2294 assert(name);
2295 assert(creds);
2296
2297 /*
2298 * Create session in no output mode with URIs set to NULL. The uris we've
2299 * received are for a default snapshot output if one.
2300 */
2301 ret = cmd_create_session_uri(name, NULL, 0, creds, -1);
2302 if (ret != LTTNG_OK) {
2303 goto error;
2304 }
2305
2306 /* Get the newly created session pointer back. This should NEVER fail. */
2307 session = session_find_by_name(name);
2308 assert(session);
2309
2310 /* Flag session for snapshot mode. */
2311 session->snapshot_mode = 1;
2312
2313 /* Skip snapshot output creation if no URI is given. */
2314 if (nb_uri == 0) {
2315 goto end;
2316 }
2317
2318 new_output = snapshot_output_alloc();
2319 if (!new_output) {
2320 ret = LTTNG_ERR_NOMEM;
2321 goto error_snapshot_alloc;
2322 }
2323
2324 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
2325 uris, nb_uri, session->consumer, new_output, &session->snapshot);
2326 if (ret < 0) {
2327 if (ret == -ENOMEM) {
2328 ret = LTTNG_ERR_NOMEM;
2329 } else {
2330 ret = LTTNG_ERR_INVALID;
2331 }
2332 goto error_snapshot;
2333 }
2334
2335 rcu_read_lock();
2336 snapshot_add_output(&session->snapshot, new_output);
2337 rcu_read_unlock();
2338
2339 end:
2340 return LTTNG_OK;
2341
2342 error_snapshot:
2343 snapshot_output_destroy(new_output);
2344 error_snapshot_alloc:
2345 session_destroy(session);
2346 error:
2347 return ret;
2348 }
2349
2350 /*
2351 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2352 *
2353 * Called with session lock held.
2354 */
2355 int cmd_destroy_session(struct ltt_session *session, int wpipe)
2356 {
2357 int ret;
2358 struct ltt_ust_session *usess;
2359 struct ltt_kernel_session *ksess;
2360
2361 /* Safety net */
2362 assert(session);
2363
2364 usess = session->ust_session;
2365 ksess = session->kernel_session;
2366
2367 /* Clean kernel session teardown */
2368 kernel_destroy_session(ksess);
2369
2370 /* UST session teardown */
2371 if (usess) {
2372 /* Close any relayd session */
2373 consumer_output_send_destroy_relayd(usess->consumer);
2374
2375 /* Destroy every UST application related to this session. */
2376 ret = ust_app_destroy_trace_all(usess);
2377 if (ret) {
2378 ERR("Error in ust_app_destroy_trace_all");
2379 }
2380
2381 /* Clean up the rest. */
2382 trace_ust_destroy_session(usess);
2383 }
2384
2385 /*
2386 * Must notify the kernel thread here to update it's poll set in order to
2387 * remove the channel(s)' fd just destroyed.
2388 */
2389 ret = notify_thread_pipe(wpipe);
2390 if (ret < 0) {
2391 PERROR("write kernel poll pipe");
2392 }
2393
2394 ret = session_destroy(session);
2395
2396 return ret;
2397 }
2398
2399 /*
2400 * Command LTTNG_CALIBRATE processed by the client thread.
2401 */
2402 int cmd_calibrate(enum lttng_domain_type domain,
2403 struct lttng_calibrate *calibrate)
2404 {
2405 int ret;
2406
2407 switch (domain) {
2408 case LTTNG_DOMAIN_KERNEL:
2409 {
2410 struct lttng_kernel_calibrate kcalibrate;
2411
2412 switch (calibrate->type) {
2413 case LTTNG_CALIBRATE_FUNCTION:
2414 default:
2415 /* Default and only possible calibrate option. */
2416 kcalibrate.type = LTTNG_KERNEL_CALIBRATE_KRETPROBE;
2417 break;
2418 }
2419
2420 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2421 if (ret < 0) {
2422 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
2423 goto error;
2424 }
2425 break;
2426 }
2427 case LTTNG_DOMAIN_UST:
2428 {
2429 struct lttng_ust_calibrate ucalibrate;
2430
2431 switch (calibrate->type) {
2432 case LTTNG_CALIBRATE_FUNCTION:
2433 default:
2434 /* Default and only possible calibrate option. */
2435 ucalibrate.type = LTTNG_UST_CALIBRATE_TRACEPOINT;
2436 break;
2437 }
2438
2439 ret = ust_app_calibrate_glb(&ucalibrate);
2440 if (ret < 0) {
2441 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
2442 goto error;
2443 }
2444 break;
2445 }
2446 default:
2447 ret = LTTNG_ERR_UND;
2448 goto error;
2449 }
2450
2451 ret = LTTNG_OK;
2452
2453 error:
2454 return ret;
2455 }
2456
2457 /*
2458 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2459 */
2460 int cmd_register_consumer(struct ltt_session *session,
2461 enum lttng_domain_type domain, const char *sock_path,
2462 struct consumer_data *cdata)
2463 {
2464 int ret, sock;
2465 struct consumer_socket *socket = NULL;
2466
2467 assert(session);
2468 assert(cdata);
2469 assert(sock_path);
2470
2471 switch (domain) {
2472 case LTTNG_DOMAIN_KERNEL:
2473 {
2474 struct ltt_kernel_session *ksess = session->kernel_session;
2475
2476 assert(ksess);
2477
2478 /* Can't register a consumer if there is already one */
2479 if (ksess->consumer_fds_sent != 0) {
2480 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2481 goto error;
2482 }
2483
2484 sock = lttcomm_connect_unix_sock(sock_path);
2485 if (sock < 0) {
2486 ret = LTTNG_ERR_CONNECT_FAIL;
2487 goto error;
2488 }
2489 cdata->cmd_sock = sock;
2490
2491 socket = consumer_allocate_socket(&cdata->cmd_sock);
2492 if (socket == NULL) {
2493 ret = close(sock);
2494 if (ret < 0) {
2495 PERROR("close register consumer");
2496 }
2497 cdata->cmd_sock = -1;
2498 ret = LTTNG_ERR_FATAL;
2499 goto error;
2500 }
2501
2502 socket->lock = zmalloc(sizeof(pthread_mutex_t));
2503 if (socket->lock == NULL) {
2504 PERROR("zmalloc pthread mutex");
2505 ret = LTTNG_ERR_FATAL;
2506 goto error;
2507 }
2508 pthread_mutex_init(socket->lock, NULL);
2509 socket->registered = 1;
2510
2511 rcu_read_lock();
2512 consumer_add_socket(socket, ksess->consumer);
2513 rcu_read_unlock();
2514
2515 pthread_mutex_lock(&cdata->pid_mutex);
2516 cdata->pid = -1;
2517 pthread_mutex_unlock(&cdata->pid_mutex);
2518
2519 break;
2520 }
2521 default:
2522 /* TODO: Userspace tracing */
2523 ret = LTTNG_ERR_UND;
2524 goto error;
2525 }
2526
2527 return LTTNG_OK;
2528
2529 error:
2530 if (socket) {
2531 consumer_destroy_socket(socket);
2532 }
2533 return ret;
2534 }
2535
2536 /*
2537 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2538 */
2539 ssize_t cmd_list_domains(struct ltt_session *session,
2540 struct lttng_domain **domains)
2541 {
2542 int ret, index = 0;
2543 ssize_t nb_dom = 0;
2544 struct agent *agt;
2545 struct lttng_ht_iter iter;
2546
2547 if (session->kernel_session != NULL) {
2548 DBG3("Listing domains found kernel domain");
2549 nb_dom++;
2550 }
2551
2552 if (session->ust_session != NULL) {
2553 DBG3("Listing domains found UST global domain");
2554 nb_dom++;
2555
2556 rcu_read_lock();
2557 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2558 agt, node.node) {
2559 if (agt->being_used) {
2560 nb_dom++;
2561 }
2562 }
2563 rcu_read_unlock();
2564 }
2565
2566 if (!nb_dom) {
2567 goto end;
2568 }
2569
2570 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2571 if (*domains == NULL) {
2572 ret = LTTNG_ERR_FATAL;
2573 goto error;
2574 }
2575
2576 if (session->kernel_session != NULL) {
2577 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2578
2579 /* Kernel session buffer type is always GLOBAL */
2580 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
2581
2582 index++;
2583 }
2584
2585 if (session->ust_session != NULL) {
2586 (*domains)[index].type = LTTNG_DOMAIN_UST;
2587 (*domains)[index].buf_type = session->ust_session->buffer_type;
2588 index++;
2589
2590 rcu_read_lock();
2591 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2592 agt, node.node) {
2593 if (agt->being_used) {
2594 (*domains)[index].type = agt->domain;
2595 (*domains)[index].buf_type = session->ust_session->buffer_type;
2596 index++;
2597 }
2598 }
2599 rcu_read_unlock();
2600 }
2601 end:
2602 return nb_dom;
2603
2604 error:
2605 /* Return negative value to differentiate return code */
2606 return -ret;
2607 }
2608
2609
2610 /*
2611 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2612 */
2613 ssize_t cmd_list_channels(enum lttng_domain_type domain,
2614 struct ltt_session *session, struct lttng_channel **channels)
2615 {
2616 int ret;
2617 ssize_t nb_chan = 0;
2618
2619 switch (domain) {
2620 case LTTNG_DOMAIN_KERNEL:
2621 if (session->kernel_session != NULL) {
2622 nb_chan = session->kernel_session->channel_count;
2623 }
2624 DBG3("Number of kernel channels %zd", nb_chan);
2625 if (nb_chan <= 0) {
2626 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
2627 }
2628 break;
2629 case LTTNG_DOMAIN_UST:
2630 if (session->ust_session != NULL) {
2631 rcu_read_lock();
2632 nb_chan = lttng_ht_get_count(
2633 session->ust_session->domain_global.channels);
2634 rcu_read_unlock();
2635 }
2636 DBG3("Number of UST global channels %zd", nb_chan);
2637 if (nb_chan < 0) {
2638 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2639 goto error;
2640 }
2641 break;
2642 default:
2643 ret = LTTNG_ERR_UND;
2644 goto error;
2645 }
2646
2647 if (nb_chan > 0) {
2648 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
2649 if (*channels == NULL) {
2650 ret = LTTNG_ERR_FATAL;
2651 goto error;
2652 }
2653
2654 list_lttng_channels(domain, session, *channels);
2655 }
2656
2657 return nb_chan;
2658
2659 error:
2660 /* Return negative value to differentiate return code */
2661 return -ret;
2662 }
2663
2664 /*
2665 * Command LTTNG_LIST_EVENTS processed by the client thread.
2666 */
2667 ssize_t cmd_list_events(enum lttng_domain_type domain,
2668 struct ltt_session *session, char *channel_name,
2669 struct lttng_event **events)
2670 {
2671 int ret = 0;
2672 ssize_t nb_event = 0;
2673
2674 switch (domain) {
2675 case LTTNG_DOMAIN_KERNEL:
2676 if (session->kernel_session != NULL) {
2677 nb_event = list_lttng_kernel_events(channel_name,
2678 session->kernel_session, events);
2679 }
2680 break;
2681 case LTTNG_DOMAIN_UST:
2682 {
2683 if (session->ust_session != NULL) {
2684 nb_event = list_lttng_ust_global_events(channel_name,
2685 &session->ust_session->domain_global, events);
2686 }
2687 break;
2688 }
2689 case LTTNG_DOMAIN_LOG4J:
2690 case LTTNG_DOMAIN_JUL:
2691 case LTTNG_DOMAIN_PYTHON:
2692 if (session->ust_session) {
2693 struct lttng_ht_iter iter;
2694 struct agent *agt;
2695
2696 rcu_read_lock();
2697 cds_lfht_for_each_entry(session->ust_session->agents->ht,
2698 &iter.iter, agt, node.node) {
2699 nb_event = list_lttng_agent_events(agt, events);
2700 }
2701 rcu_read_unlock();
2702 }
2703 break;
2704 default:
2705 ret = LTTNG_ERR_UND;
2706 goto error;
2707 }
2708
2709 return nb_event;
2710
2711 error:
2712 /* Return negative value to differentiate return code */
2713 return -ret;
2714 }
2715
2716 /*
2717 * Using the session list, filled a lttng_session array to send back to the
2718 * client for session listing.
2719 *
2720 * The session list lock MUST be acquired before calling this function. Use
2721 * session_lock_list() and session_unlock_list().
2722 */
2723 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2724 gid_t gid)
2725 {
2726 int ret;
2727 unsigned int i = 0;
2728 struct ltt_session *session;
2729 struct ltt_session_list *list = session_get_list();
2730
2731 DBG("Getting all available session for UID %d GID %d",
2732 uid, gid);
2733 /*
2734 * Iterate over session list and append data after the control struct in
2735 * the buffer.
2736 */
2737 cds_list_for_each_entry(session, &list->head, list) {
2738 /*
2739 * Only list the sessions the user can control.
2740 */
2741 if (!session_access_ok(session, uid, gid)) {
2742 continue;
2743 }
2744
2745 struct ltt_kernel_session *ksess = session->kernel_session;
2746 struct ltt_ust_session *usess = session->ust_session;
2747
2748 if (session->consumer->type == CONSUMER_DST_NET ||
2749 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2750 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2751 ret = build_network_session_path(sessions[i].path,
2752 sizeof(sessions[i].path), session);
2753 } else {
2754 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
2755 session->consumer->dst.trace_path);
2756 }
2757 if (ret < 0) {
2758 PERROR("snprintf session path");
2759 continue;
2760 }
2761
2762 strncpy(sessions[i].name, session->name, NAME_MAX);
2763 sessions[i].name[NAME_MAX - 1] = '\0';
2764 sessions[i].enabled = session->active;
2765 sessions[i].snapshot_mode = session->snapshot_mode;
2766 sessions[i].live_timer_interval = session->live_timer;
2767 i++;
2768 }
2769 }
2770
2771 /*
2772 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2773 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
2774 */
2775 int cmd_data_pending(struct ltt_session *session)
2776 {
2777 int ret;
2778 struct ltt_kernel_session *ksess = session->kernel_session;
2779 struct ltt_ust_session *usess = session->ust_session;
2780
2781 assert(session);
2782
2783 /* Session MUST be stopped to ask for data availability. */
2784 if (session->active) {
2785 ret = LTTNG_ERR_SESSION_STARTED;
2786 goto error;
2787 } else {
2788 /*
2789 * If stopped, just make sure we've started before else the above call
2790 * will always send that there is data pending.
2791 *
2792 * The consumer assumes that when the data pending command is received,
2793 * the trace has been started before or else no output data is written
2794 * by the streams which is a condition for data pending. So, this is
2795 * *VERY* important that we don't ask the consumer before a start
2796 * trace.
2797 */
2798 if (!session->has_been_started) {
2799 ret = 0;
2800 goto error;
2801 }
2802 }
2803
2804 if (ksess && ksess->consumer) {
2805 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2806 if (ret == 1) {
2807 /* Data is still being extracted for the kernel. */
2808 goto error;
2809 }
2810 }
2811
2812 if (usess && usess->consumer) {
2813 ret = consumer_is_data_pending(usess->id, usess->consumer);
2814 if (ret == 1) {
2815 /* Data is still being extracted for the kernel. */
2816 goto error;
2817 }
2818 }
2819
2820 /* Data is ready to be read by a viewer */
2821 ret = 0;
2822
2823 error:
2824 return ret;
2825 }
2826
2827 /*
2828 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
2829 *
2830 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2831 */
2832 int cmd_snapshot_add_output(struct ltt_session *session,
2833 struct lttng_snapshot_output *output, uint32_t *id)
2834 {
2835 int ret;
2836 struct snapshot_output *new_output;
2837
2838 assert(session);
2839 assert(output);
2840
2841 DBG("Cmd snapshot add output for session %s", session->name);
2842
2843 /*
2844 * Permission denied to create an output if the session is not
2845 * set in no output mode.
2846 */
2847 if (session->output_traces) {
2848 ret = LTTNG_ERR_EPERM;
2849 goto error;
2850 }
2851
2852 /* Only one output is allowed until we have the "tee" feature. */
2853 if (session->snapshot.nb_output == 1) {
2854 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
2855 goto error;
2856 }
2857
2858 new_output = snapshot_output_alloc();
2859 if (!new_output) {
2860 ret = LTTNG_ERR_NOMEM;
2861 goto error;
2862 }
2863
2864 ret = snapshot_output_init(output->max_size, output->name,
2865 output->ctrl_url, output->data_url, session->consumer, new_output,
2866 &session->snapshot);
2867 if (ret < 0) {
2868 if (ret == -ENOMEM) {
2869 ret = LTTNG_ERR_NOMEM;
2870 } else {
2871 ret = LTTNG_ERR_INVALID;
2872 }
2873 goto free_error;
2874 }
2875
2876 rcu_read_lock();
2877 snapshot_add_output(&session->snapshot, new_output);
2878 if (id) {
2879 *id = new_output->id;
2880 }
2881 rcu_read_unlock();
2882
2883 return LTTNG_OK;
2884
2885 free_error:
2886 snapshot_output_destroy(new_output);
2887 error:
2888 return ret;
2889 }
2890
2891 /*
2892 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
2893 *
2894 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2895 */
2896 int cmd_snapshot_del_output(struct ltt_session *session,
2897 struct lttng_snapshot_output *output)
2898 {
2899 int ret;
2900 struct snapshot_output *sout = NULL;
2901
2902 assert(session);
2903 assert(output);
2904
2905 rcu_read_lock();
2906
2907 /*
2908 * Permission denied to create an output if the session is not
2909 * set in no output mode.
2910 */
2911 if (session->output_traces) {
2912 ret = LTTNG_ERR_EPERM;
2913 goto error;
2914 }
2915
2916 if (output->id) {
2917 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
2918 session->name);
2919 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
2920 } else if (*output->name != '\0') {
2921 DBG("Cmd snapshot del output name %s for session %s", output->name,
2922 session->name);
2923 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
2924 }
2925 if (!sout) {
2926 ret = LTTNG_ERR_INVALID;
2927 goto error;
2928 }
2929
2930 snapshot_delete_output(&session->snapshot, sout);
2931 snapshot_output_destroy(sout);
2932 ret = LTTNG_OK;
2933
2934 error:
2935 rcu_read_unlock();
2936 return ret;
2937 }
2938
2939 /*
2940 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
2941 *
2942 * If no output is available, outputs is untouched and 0 is returned.
2943 *
2944 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
2945 */
2946 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
2947 struct lttng_snapshot_output **outputs)
2948 {
2949 int ret, idx = 0;
2950 struct lttng_snapshot_output *list = NULL;
2951 struct lttng_ht_iter iter;
2952 struct snapshot_output *output;
2953
2954 assert(session);
2955 assert(outputs);
2956
2957 DBG("Cmd snapshot list outputs for session %s", session->name);
2958
2959 /*
2960 * Permission denied to create an output if the session is not
2961 * set in no output mode.
2962 */
2963 if (session->output_traces) {
2964 ret = -LTTNG_ERR_EPERM;
2965 goto error;
2966 }
2967
2968 if (session->snapshot.nb_output == 0) {
2969 ret = 0;
2970 goto error;
2971 }
2972
2973 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
2974 if (!list) {
2975 ret = -LTTNG_ERR_NOMEM;
2976 goto error;
2977 }
2978
2979 /* Copy list from session to the new list object. */
2980 rcu_read_lock();
2981 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
2982 output, node.node) {
2983 assert(output->consumer);
2984 list[idx].id = output->id;
2985 list[idx].max_size = output->max_size;
2986 strncpy(list[idx].name, output->name, sizeof(list[idx].name));
2987 if (output->consumer->type == CONSUMER_DST_LOCAL) {
2988 strncpy(list[idx].ctrl_url, output->consumer->dst.trace_path,
2989 sizeof(list[idx].ctrl_url));
2990 } else {
2991 /* Control URI. */
2992 ret = uri_to_str_url(&output->consumer->dst.net.control,
2993 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
2994 if (ret < 0) {
2995 ret = -LTTNG_ERR_NOMEM;
2996 goto error;
2997 }
2998
2999 /* Data URI. */
3000 ret = uri_to_str_url(&output->consumer->dst.net.data,
3001 list[idx].data_url, sizeof(list[idx].data_url));
3002 if (ret < 0) {
3003 ret = -LTTNG_ERR_NOMEM;
3004 goto error;
3005 }
3006 }
3007 idx++;
3008 }
3009
3010 *outputs = list;
3011 list = NULL;
3012 ret = session->snapshot.nb_output;
3013 error:
3014 free(list);
3015 rcu_read_unlock();
3016 return ret;
3017 }
3018
3019 /*
3020 * Send relayd sockets from snapshot output to consumer. Ignore request if the
3021 * snapshot output is *not* set with a remote destination.
3022 *
3023 * Return 0 on success or a LTTNG_ERR code.
3024 */
3025 static int set_relayd_for_snapshot(struct consumer_output *consumer,
3026 struct snapshot_output *snap_output, struct ltt_session *session)
3027 {
3028 int ret = LTTNG_OK;
3029 struct lttng_ht_iter iter;
3030 struct consumer_socket *socket;
3031
3032 assert(consumer);
3033 assert(snap_output);
3034 assert(session);
3035
3036 DBG2("Set relayd object from snapshot output");
3037
3038 /* Ignore if snapshot consumer output is not network. */
3039 if (snap_output->consumer->type != CONSUMER_DST_NET) {
3040 goto error;
3041 }
3042
3043 /*
3044 * For each consumer socket, create and send the relayd object of the
3045 * snapshot output.
3046 */
3047 rcu_read_lock();
3048 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
3049 socket, node.node) {
3050 ret = send_consumer_relayd_sockets(0, session->id,
3051 snap_output->consumer, socket,
3052 session->name, session->hostname,
3053 session->live_timer);
3054 if (ret != LTTNG_OK) {
3055 rcu_read_unlock();
3056 goto error;
3057 }
3058 }
3059 rcu_read_unlock();
3060
3061 error:
3062 return ret;
3063 }
3064
3065 /*
3066 * Record a kernel snapshot.
3067 *
3068 * Return LTTNG_OK on success or a LTTNG_ERR code.
3069 */
3070 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
3071 struct snapshot_output *output, struct ltt_session *session,
3072 int wait, uint64_t nb_packets_per_stream)
3073 {
3074 int ret;
3075
3076 assert(ksess);
3077 assert(output);
3078 assert(session);
3079
3080 /* Get the datetime for the snapshot output directory. */
3081 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
3082 sizeof(output->datetime));
3083 if (!ret) {
3084 ret = LTTNG_ERR_INVALID;
3085 goto error;
3086 }
3087
3088 /*
3089 * Copy kernel session sockets so we can communicate with the right
3090 * consumer for the snapshot record command.
3091 */
3092 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
3093 if (ret < 0) {
3094 ret = LTTNG_ERR_NOMEM;
3095 goto error;
3096 }
3097
3098 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
3099 if (ret != LTTNG_OK) {
3100 goto error_snapshot;
3101 }
3102
3103 ret = kernel_snapshot_record(ksess, output, wait, nb_packets_per_stream);
3104 if (ret != LTTNG_OK) {
3105 goto error_snapshot;
3106 }
3107
3108 ret = LTTNG_OK;
3109 goto end;
3110
3111 error_snapshot:
3112 /* Clean up copied sockets so this output can use some other later on. */
3113 consumer_destroy_output_sockets(output->consumer);
3114 error:
3115 end:
3116 return ret;
3117 }
3118
3119 /*
3120 * Record a UST snapshot.
3121 *
3122 * Return 0 on success or a LTTNG_ERR error code.
3123 */
3124 static int record_ust_snapshot(struct ltt_ust_session *usess,
3125 struct snapshot_output *output, struct ltt_session *session,
3126 int wait, uint64_t nb_packets_per_stream)
3127 {
3128 int ret;
3129
3130 assert(usess);
3131 assert(output);
3132 assert(session);
3133
3134 /* Get the datetime for the snapshot output directory. */
3135 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
3136 sizeof(output->datetime));
3137 if (!ret) {
3138 ret = LTTNG_ERR_INVALID;
3139 goto error;
3140 }
3141
3142 /*
3143 * Copy UST session sockets so we can communicate with the right
3144 * consumer for the snapshot record command.
3145 */
3146 ret = consumer_copy_sockets(output->consumer, usess->consumer);
3147 if (ret < 0) {
3148 ret = LTTNG_ERR_NOMEM;
3149 goto error;
3150 }
3151
3152 ret = set_relayd_for_snapshot(usess->consumer, output, session);
3153 if (ret != LTTNG_OK) {
3154 goto error_snapshot;
3155 }
3156
3157 ret = ust_app_snapshot_record(usess, output, wait, nb_packets_per_stream);
3158 if (ret < 0) {
3159 switch (-ret) {
3160 case EINVAL:
3161 ret = LTTNG_ERR_INVALID;
3162 break;
3163 case ENODATA:
3164 ret = LTTNG_ERR_SNAPSHOT_NODATA;
3165 break;
3166 default:
3167 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3168 break;
3169 }
3170 goto error_snapshot;
3171 }
3172
3173 ret = LTTNG_OK;
3174
3175 error_snapshot:
3176 /* Clean up copied sockets so this output can use some other later on. */
3177 consumer_destroy_output_sockets(output->consumer);
3178 error:
3179 return ret;
3180 }
3181
3182 static
3183 uint64_t get_session_size_one_more_packet_per_stream(struct ltt_session *session,
3184 uint64_t cur_nr_packets)
3185 {
3186 uint64_t tot_size = 0;
3187
3188 if (session->kernel_session) {
3189 struct ltt_kernel_channel *chan;
3190 struct ltt_kernel_session *ksess = session->kernel_session;
3191
3192 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
3193 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
3194 /*
3195 * Don't take channel into account if we
3196 * already grab all its packets.
3197 */
3198 continue;
3199 }
3200 tot_size += chan->channel->attr.subbuf_size
3201 * chan->stream_count;
3202 }
3203 }
3204
3205 if (session->ust_session) {
3206 struct ltt_ust_session *usess = session->ust_session;
3207
3208 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
3209 cur_nr_packets);
3210 }
3211
3212 return tot_size;
3213 }
3214
3215 /*
3216 * Calculate the number of packets we can grab from each stream that
3217 * fits within the overall snapshot max size.
3218 *
3219 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
3220 * the number of packets per stream.
3221 *
3222 * TODO: this approach is not perfect: we consider the worse case
3223 * (packet filling the sub-buffers) as an upper bound, but we could do
3224 * better if we do this calculation while we actually grab the packet
3225 * content: we would know how much padding we don't actually store into
3226 * the file.
3227 *
3228 * This algorithm is currently bounded by the number of packets per
3229 * stream.
3230 *
3231 * Since we call this algorithm before actually grabbing the data, it's
3232 * an approximation: for instance, applications could appear/disappear
3233 * in between this call and actually grabbing data.
3234 */
3235 static
3236 int64_t get_session_nb_packets_per_stream(struct ltt_session *session, uint64_t max_size)
3237 {
3238 int64_t size_left;
3239 uint64_t cur_nb_packets = 0;
3240
3241 if (!max_size) {
3242 return 0; /* Infinite */
3243 }
3244
3245 size_left = max_size;
3246 for (;;) {
3247 uint64_t one_more_packet_tot_size;
3248
3249 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(session,
3250 cur_nb_packets);
3251 if (!one_more_packet_tot_size) {
3252 /* We are already grabbing all packets. */
3253 break;
3254 }
3255 size_left -= one_more_packet_tot_size;
3256 if (size_left < 0) {
3257 break;
3258 }
3259 cur_nb_packets++;
3260 }
3261 if (!cur_nb_packets) {
3262 /* Not enough room to grab one packet of each stream, error. */
3263 return -1;
3264 }
3265 return cur_nb_packets;
3266 }
3267
3268 /*
3269 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
3270 *
3271 * The wait parameter is ignored so this call always wait for the snapshot to
3272 * complete before returning.
3273 *
3274 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3275 */
3276 int cmd_snapshot_record(struct ltt_session *session,
3277 struct lttng_snapshot_output *output, int wait)
3278 {
3279 int ret = LTTNG_OK;
3280 unsigned int use_tmp_output = 0;
3281 struct snapshot_output tmp_output;
3282 unsigned int snapshot_success = 0;
3283
3284 assert(session);
3285 assert(output);
3286
3287 DBG("Cmd snapshot record for session %s", session->name);
3288
3289 /*
3290 * Permission denied to create an output if the session is not
3291 * set in no output mode.
3292 */
3293 if (session->output_traces) {
3294 ret = LTTNG_ERR_EPERM;
3295 goto error;
3296 }
3297
3298 /* The session needs to be started at least once. */
3299 if (!session->has_been_started) {
3300 ret = LTTNG_ERR_START_SESSION_ONCE;
3301 goto error;
3302 }
3303
3304 /* Use temporary output for the session. */
3305 if (*output->ctrl_url != '\0') {
3306 ret = snapshot_output_init(output->max_size, output->name,
3307 output->ctrl_url, output->data_url, session->consumer,
3308 &tmp_output, NULL);
3309 if (ret < 0) {
3310 if (ret == -ENOMEM) {
3311 ret = LTTNG_ERR_NOMEM;
3312 } else {
3313 ret = LTTNG_ERR_INVALID;
3314 }
3315 goto error;
3316 }
3317 /* Use the global session count for the temporary snapshot. */
3318 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3319 use_tmp_output = 1;
3320 }
3321
3322 if (session->kernel_session) {
3323 struct ltt_kernel_session *ksess = session->kernel_session;
3324
3325 if (use_tmp_output) {
3326 int64_t nb_packets_per_stream;
3327
3328 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3329 tmp_output.max_size);
3330 if (nb_packets_per_stream < 0) {
3331 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3332 goto error;
3333 }
3334 ret = record_kernel_snapshot(ksess, &tmp_output, session,
3335 wait, nb_packets_per_stream);
3336 if (ret != LTTNG_OK) {
3337 goto error;
3338 }
3339 snapshot_success = 1;
3340 } else {
3341 struct snapshot_output *sout;
3342 struct lttng_ht_iter iter;
3343
3344 rcu_read_lock();
3345 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3346 &iter.iter, sout, node.node) {
3347 int64_t nb_packets_per_stream;
3348
3349 /*
3350 * Make a local copy of the output and assign the possible
3351 * temporary value given by the caller.
3352 */
3353 memset(&tmp_output, 0, sizeof(tmp_output));
3354 memcpy(&tmp_output, sout, sizeof(tmp_output));
3355
3356 if (output->max_size != (uint64_t) -1ULL) {
3357 tmp_output.max_size = output->max_size;
3358 }
3359
3360 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3361 tmp_output.max_size);
3362 if (nb_packets_per_stream < 0) {
3363 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3364 goto error;
3365 }
3366
3367 /* Use temporary name. */
3368 if (*output->name != '\0') {
3369 strncpy(tmp_output.name, output->name,
3370 sizeof(tmp_output.name));
3371 }
3372
3373 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3374
3375 ret = record_kernel_snapshot(ksess, &tmp_output,
3376 session, wait, nb_packets_per_stream);
3377 if (ret != LTTNG_OK) {
3378 rcu_read_unlock();
3379 goto error;
3380 }
3381 snapshot_success = 1;
3382 }
3383 rcu_read_unlock();
3384 }
3385 }
3386
3387 if (session->ust_session) {
3388 struct ltt_ust_session *usess = session->ust_session;
3389
3390 if (use_tmp_output) {
3391 int64_t nb_packets_per_stream;
3392
3393 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3394 tmp_output.max_size);
3395 if (nb_packets_per_stream < 0) {
3396 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3397 goto error;
3398 }
3399 ret = record_ust_snapshot(usess, &tmp_output, session,
3400 wait, nb_packets_per_stream);
3401 if (ret != LTTNG_OK) {
3402 goto error;
3403 }
3404 snapshot_success = 1;
3405 } else {
3406 struct snapshot_output *sout;
3407 struct lttng_ht_iter iter;
3408
3409 rcu_read_lock();
3410 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3411 &iter.iter, sout, node.node) {
3412 int64_t nb_packets_per_stream;
3413
3414 /*
3415 * Make a local copy of the output and assign the possible
3416 * temporary value given by the caller.
3417 */
3418 memset(&tmp_output, 0, sizeof(tmp_output));
3419 memcpy(&tmp_output, sout, sizeof(tmp_output));
3420
3421 if (output->max_size != (uint64_t) -1ULL) {
3422 tmp_output.max_size = output->max_size;
3423 }
3424
3425 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3426 tmp_output.max_size);
3427 if (nb_packets_per_stream < 0) {
3428 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3429 rcu_read_unlock();
3430 goto error;
3431 }
3432
3433 /* Use temporary name. */
3434 if (*output->name != '\0') {
3435 strncpy(tmp_output.name, output->name,
3436 sizeof(tmp_output.name));
3437 }
3438
3439 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3440
3441 ret = record_ust_snapshot(usess, &tmp_output, session,
3442 wait, nb_packets_per_stream);
3443 if (ret != LTTNG_OK) {
3444 rcu_read_unlock();
3445 goto error;
3446 }
3447 snapshot_success = 1;
3448 }
3449 rcu_read_unlock();
3450 }
3451 }
3452
3453 if (snapshot_success) {
3454 session->snapshot.nb_snapshot++;
3455 } else {
3456 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3457 }
3458
3459 error:
3460 return ret;
3461 }
3462
3463 /*
3464 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
3465 */
3466 int cmd_set_session_shm_path(struct ltt_session *session,
3467 const char *shm_path)
3468 {
3469 /* Safety net */
3470 assert(session);
3471
3472 /*
3473 * Can only set shm path before session is started.
3474 */
3475 if (session->has_been_started) {
3476 return LTTNG_ERR_SESSION_STARTED;
3477 }
3478
3479 strncpy(session->shm_path, shm_path,
3480 sizeof(session->shm_path));
3481 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
3482
3483 return 0;
3484 }
3485
3486 /*
3487 * Init command subsystem.
3488 */
3489 void cmd_init(void)
3490 {
3491 /*
3492 * Set network sequence index to 1 for streams to match a relayd
3493 * socket on the consumer side.
3494 */
3495 pthread_mutex_lock(&relayd_net_seq_idx_lock);
3496 relayd_net_seq_idx = 1;
3497 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
3498
3499 DBG("Command subsystem initialized");
3500 }
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