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Remove unneeded RCU lock
[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 /*
55 * Create a session path used by list_lttng_sessions for the case that the
56 * session consumer is on the network.
57 */
58 static int build_network_session_path(char *dst, size_t size,
59 struct ltt_session *session)
60 {
61 int ret, kdata_port, udata_port;
62 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
63 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
64
65 assert(session);
66 assert(dst);
67
68 memset(tmp_urls, 0, sizeof(tmp_urls));
69 memset(tmp_uurl, 0, sizeof(tmp_uurl));
70
71 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
72
73 if (session->kernel_session && session->kernel_session->consumer) {
74 kuri = &session->kernel_session->consumer->dst.net.control;
75 kdata_port = session->kernel_session->consumer->dst.net.data.port;
76 }
77
78 if (session->ust_session && session->ust_session->consumer) {
79 uuri = &session->ust_session->consumer->dst.net.control;
80 udata_port = session->ust_session->consumer->dst.net.data.port;
81 }
82
83 if (uuri == NULL && kuri == NULL) {
84 uri = &session->consumer->dst.net.control;
85 kdata_port = session->consumer->dst.net.data.port;
86 } else if (kuri && uuri) {
87 ret = uri_compare(kuri, uuri);
88 if (ret) {
89 /* Not Equal */
90 uri = kuri;
91 /* Build uuri URL string */
92 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
93 if (ret < 0) {
94 goto error;
95 }
96 } else {
97 uri = kuri;
98 }
99 } else if (kuri && uuri == NULL) {
100 uri = kuri;
101 } else if (uuri && kuri == NULL) {
102 uri = uuri;
103 }
104
105 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
106 if (ret < 0) {
107 goto error;
108 }
109
110 /*
111 * Do we have a UST url set. If yes, this means we have both kernel and UST
112 * to print.
113 */
114 if (*tmp_uurl != '\0') {
115 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
116 tmp_urls, kdata_port, tmp_uurl, udata_port);
117 } else {
118 int dport;
119 if (kuri || (!kuri && !uuri)) {
120 dport = kdata_port;
121 } else {
122 /* No kernel URI, use the UST port. */
123 dport = udata_port;
124 }
125 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
126 }
127
128 error:
129 return ret;
130 }
131
132 /*
133 * Fill lttng_channel array of all channels.
134 */
135 static void list_lttng_channels(int domain, struct ltt_session *session,
136 struct lttng_channel *channels)
137 {
138 int i = 0;
139 struct ltt_kernel_channel *kchan;
140
141 DBG("Listing channels for session %s", session->name);
142
143 switch (domain) {
144 case LTTNG_DOMAIN_KERNEL:
145 /* Kernel channels */
146 if (session->kernel_session != NULL) {
147 cds_list_for_each_entry(kchan,
148 &session->kernel_session->channel_list.head, list) {
149 /* Copy lttng_channel struct to array */
150 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
151 channels[i].enabled = kchan->enabled;
152 i++;
153 }
154 }
155 break;
156 case LTTNG_DOMAIN_UST:
157 {
158 struct lttng_ht_iter iter;
159 struct ltt_ust_channel *uchan;
160
161 rcu_read_lock();
162 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
163 &iter.iter, uchan, node.node) {
164 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
165 channels[i].attr.overwrite = uchan->attr.overwrite;
166 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
167 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
168 channels[i].attr.switch_timer_interval =
169 uchan->attr.switch_timer_interval;
170 channels[i].attr.read_timer_interval =
171 uchan->attr.read_timer_interval;
172 channels[i].enabled = uchan->enabled;
173 channels[i].attr.tracefile_size = uchan->tracefile_size;
174 channels[i].attr.tracefile_count = uchan->tracefile_count;
175 switch (uchan->attr.output) {
176 case LTTNG_UST_MMAP:
177 default:
178 channels[i].attr.output = LTTNG_EVENT_MMAP;
179 break;
180 }
181 i++;
182 }
183 rcu_read_unlock();
184 break;
185 }
186 default:
187 break;
188 }
189 }
190
191 /*
192 * Create a list of agent domain events.
193 *
194 * Return number of events in list on success or else a negative value.
195 */
196 static int list_lttng_agent_events(struct agent *agt,
197 struct lttng_event **events)
198 {
199 int i = 0, ret = 0;
200 unsigned int nb_event = 0;
201 struct agent_event *event;
202 struct lttng_event *tmp_events;
203 struct lttng_ht_iter iter;
204
205 assert(agt);
206 assert(events);
207
208 DBG3("Listing agent events");
209
210 rcu_read_lock();
211 nb_event = lttng_ht_get_count(agt->events);
212 rcu_read_unlock();
213 if (nb_event == 0) {
214 ret = nb_event;
215 goto error;
216 }
217
218 tmp_events = zmalloc(nb_event * sizeof(*tmp_events));
219 if (!tmp_events) {
220 PERROR("zmalloc agent events session");
221 ret = -LTTNG_ERR_FATAL;
222 goto error;
223 }
224
225 rcu_read_lock();
226 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
227 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
228 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
229 tmp_events[i].enabled = event->enabled;
230 tmp_events[i].loglevel = event->loglevel;
231 tmp_events[i].loglevel_type = event->loglevel_type;
232 i++;
233 }
234 rcu_read_unlock();
235
236 *events = tmp_events;
237 ret = nb_event;
238
239 error:
240 assert(nb_event == i);
241 return ret;
242 }
243
244 /*
245 * Create a list of ust global domain events.
246 */
247 static int list_lttng_ust_global_events(char *channel_name,
248 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
249 {
250 int i = 0, ret = 0;
251 unsigned int nb_event = 0;
252 struct lttng_ht_iter iter;
253 struct lttng_ht_node_str *node;
254 struct ltt_ust_channel *uchan;
255 struct ltt_ust_event *uevent;
256 struct lttng_event *tmp;
257
258 DBG("Listing UST global events for channel %s", channel_name);
259
260 rcu_read_lock();
261
262 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
263 node = lttng_ht_iter_get_node_str(&iter);
264 if (node == NULL) {
265 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
266 goto error;
267 }
268
269 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
270
271 nb_event += lttng_ht_get_count(uchan->events);
272
273 if (nb_event == 0) {
274 ret = nb_event;
275 goto error;
276 }
277
278 DBG3("Listing UST global %d events", nb_event);
279
280 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
281 if (tmp == NULL) {
282 ret = LTTNG_ERR_FATAL;
283 goto error;
284 }
285
286 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
287 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
288 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
289 tmp[i].enabled = uevent->enabled;
290
291 switch (uevent->attr.instrumentation) {
292 case LTTNG_UST_TRACEPOINT:
293 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
294 break;
295 case LTTNG_UST_PROBE:
296 tmp[i].type = LTTNG_EVENT_PROBE;
297 break;
298 case LTTNG_UST_FUNCTION:
299 tmp[i].type = LTTNG_EVENT_FUNCTION;
300 break;
301 }
302
303 tmp[i].loglevel = uevent->attr.loglevel;
304 switch (uevent->attr.loglevel_type) {
305 case LTTNG_UST_LOGLEVEL_ALL:
306 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
307 break;
308 case LTTNG_UST_LOGLEVEL_RANGE:
309 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
310 break;
311 case LTTNG_UST_LOGLEVEL_SINGLE:
312 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
313 break;
314 }
315 if (uevent->filter) {
316 tmp[i].filter = 1;
317 }
318 if (uevent->exclusion) {
319 tmp[i].exclusion = 1;
320 }
321 i++;
322 }
323
324 ret = nb_event;
325 *events = tmp;
326
327 error:
328 rcu_read_unlock();
329 return ret;
330 }
331
332 /*
333 * Fill lttng_event array of all kernel events in the channel.
334 */
335 static int list_lttng_kernel_events(char *channel_name,
336 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
337 {
338 int i = 0, ret;
339 unsigned int nb_event;
340 struct ltt_kernel_event *event;
341 struct ltt_kernel_channel *kchan;
342
343 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
344 if (kchan == NULL) {
345 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
346 goto error;
347 }
348
349 nb_event = kchan->event_count;
350
351 DBG("Listing events for channel %s", kchan->channel->name);
352
353 if (nb_event == 0) {
354 *events = NULL;
355 goto syscall;
356 }
357
358 *events = zmalloc(nb_event * sizeof(struct lttng_event));
359 if (*events == NULL) {
360 ret = LTTNG_ERR_FATAL;
361 goto error;
362 }
363
364 /* Kernel channels */
365 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
366 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
367 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
368 (*events)[i].enabled = event->enabled;
369
370 switch (event->event->instrumentation) {
371 case LTTNG_KERNEL_TRACEPOINT:
372 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
373 break;
374 case LTTNG_KERNEL_KRETPROBE:
375 (*events)[i].type = LTTNG_EVENT_FUNCTION;
376 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
377 sizeof(struct lttng_kernel_kprobe));
378 break;
379 case LTTNG_KERNEL_KPROBE:
380 (*events)[i].type = LTTNG_EVENT_PROBE;
381 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
382 sizeof(struct lttng_kernel_kprobe));
383 break;
384 case LTTNG_KERNEL_FUNCTION:
385 (*events)[i].type = LTTNG_EVENT_FUNCTION;
386 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
387 sizeof(struct lttng_kernel_function));
388 break;
389 case LTTNG_KERNEL_NOOP:
390 (*events)[i].type = LTTNG_EVENT_NOOP;
391 break;
392 case LTTNG_KERNEL_SYSCALL:
393 (*events)[i].type = LTTNG_EVENT_SYSCALL;
394 break;
395 case LTTNG_KERNEL_ALL:
396 assert(0);
397 break;
398 }
399 i++;
400 }
401
402 syscall:
403 if (syscall_table) {
404 ssize_t new_size;
405
406 new_size = syscall_list_channel(kchan, events, nb_event);
407 if (new_size < 0) {
408 free(events);
409 ret = -new_size;
410 goto error;
411 }
412 nb_event = new_size;
413 }
414
415 return nb_event;
416
417 error:
418 /* Negate the error code to differentiate the size from an error */
419 return -ret;
420 }
421
422 /*
423 * Add URI so the consumer output object. Set the correct path depending on the
424 * domain adding the default trace directory.
425 */
426 static int add_uri_to_consumer(struct consumer_output *consumer,
427 struct lttng_uri *uri, int domain, const char *session_name)
428 {
429 int ret = LTTNG_OK;
430 const char *default_trace_dir;
431
432 assert(uri);
433
434 if (consumer == NULL) {
435 DBG("No consumer detected. Don't add URI. Stopping.");
436 ret = LTTNG_ERR_NO_CONSUMER;
437 goto error;
438 }
439
440 switch (domain) {
441 case LTTNG_DOMAIN_KERNEL:
442 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
443 break;
444 case LTTNG_DOMAIN_UST:
445 default_trace_dir = DEFAULT_UST_TRACE_DIR;
446 break;
447 default:
448 /*
449 * This case is possible is we try to add the URI to the global tracing
450 * session consumer object which in this case there is no subdir.
451 */
452 default_trace_dir = "";
453 }
454
455 switch (uri->dtype) {
456 case LTTNG_DST_IPV4:
457 case LTTNG_DST_IPV6:
458 DBG2("Setting network URI to consumer");
459
460 if (consumer->type == CONSUMER_DST_NET) {
461 if ((uri->stype == LTTNG_STREAM_CONTROL &&
462 consumer->dst.net.control_isset) ||
463 (uri->stype == LTTNG_STREAM_DATA &&
464 consumer->dst.net.data_isset)) {
465 ret = LTTNG_ERR_URL_EXIST;
466 goto error;
467 }
468 } else {
469 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
470 }
471
472 consumer->type = CONSUMER_DST_NET;
473
474 /* Set URI into consumer output object */
475 ret = consumer_set_network_uri(consumer, uri);
476 if (ret < 0) {
477 ret = -ret;
478 goto error;
479 } else if (ret == 1) {
480 /*
481 * URI was the same in the consumer so we do not append the subdir
482 * again so to not duplicate output dir.
483 */
484 ret = LTTNG_OK;
485 goto error;
486 }
487
488 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
489 ret = consumer_set_subdir(consumer, session_name);
490 if (ret < 0) {
491 ret = LTTNG_ERR_FATAL;
492 goto error;
493 }
494 }
495
496 if (uri->stype == LTTNG_STREAM_CONTROL) {
497 /* On a new subdir, reappend the default trace dir. */
498 strncat(consumer->subdir, default_trace_dir,
499 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
500 DBG3("Append domain trace name to subdir %s", consumer->subdir);
501 }
502
503 break;
504 case LTTNG_DST_PATH:
505 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
506 memset(consumer->dst.trace_path, 0,
507 sizeof(consumer->dst.trace_path));
508 strncpy(consumer->dst.trace_path, uri->dst.path,
509 sizeof(consumer->dst.trace_path));
510 /* Append default trace dir */
511 strncat(consumer->dst.trace_path, default_trace_dir,
512 sizeof(consumer->dst.trace_path) -
513 strlen(consumer->dst.trace_path) - 1);
514 /* Flag consumer as local. */
515 consumer->type = CONSUMER_DST_LOCAL;
516 break;
517 }
518
519 ret = LTTNG_OK;
520
521 error:
522 return ret;
523 }
524
525 /*
526 * Init tracing by creating trace directory and sending fds kernel consumer.
527 */
528 static int init_kernel_tracing(struct ltt_kernel_session *session)
529 {
530 int ret = 0;
531 struct lttng_ht_iter iter;
532 struct consumer_socket *socket;
533
534 assert(session);
535
536 rcu_read_lock();
537
538 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
539 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
540 socket, node.node) {
541 pthread_mutex_lock(socket->lock);
542 ret = kernel_consumer_send_session(socket, session);
543 pthread_mutex_unlock(socket->lock);
544 if (ret < 0) {
545 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
546 goto error;
547 }
548 }
549 }
550
551 error:
552 rcu_read_unlock();
553 return ret;
554 }
555
556 /*
557 * Create a socket to the relayd using the URI.
558 *
559 * On success, the relayd_sock pointer is set to the created socket.
560 * Else, it's stays untouched and a lttcomm error code is returned.
561 */
562 static int create_connect_relayd(struct lttng_uri *uri,
563 struct lttcomm_relayd_sock **relayd_sock)
564 {
565 int ret;
566 struct lttcomm_relayd_sock *rsock;
567
568 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
569 RELAYD_VERSION_COMM_MINOR);
570 if (!rsock) {
571 ret = LTTNG_ERR_FATAL;
572 goto error;
573 }
574
575 /*
576 * Connect to relayd so we can proceed with a session creation. This call
577 * can possibly block for an arbitrary amount of time to set the health
578 * state to be in poll execution.
579 */
580 health_poll_entry();
581 ret = relayd_connect(rsock);
582 health_poll_exit();
583 if (ret < 0) {
584 ERR("Unable to reach lttng-relayd");
585 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
586 goto free_sock;
587 }
588
589 /* Create socket for control stream. */
590 if (uri->stype == LTTNG_STREAM_CONTROL) {
591 DBG3("Creating relayd stream socket from URI");
592
593 /* Check relayd version */
594 ret = relayd_version_check(rsock);
595 if (ret < 0) {
596 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
597 goto close_sock;
598 }
599 } else if (uri->stype == LTTNG_STREAM_DATA) {
600 DBG3("Creating relayd data socket from URI");
601 } else {
602 /* Command is not valid */
603 ERR("Relayd invalid stream type: %d", uri->stype);
604 ret = LTTNG_ERR_INVALID;
605 goto close_sock;
606 }
607
608 *relayd_sock = rsock;
609
610 return LTTNG_OK;
611
612 close_sock:
613 /* The returned value is not useful since we are on an error path. */
614 (void) relayd_close(rsock);
615 free_sock:
616 free(rsock);
617 error:
618 return ret;
619 }
620
621 /*
622 * Connect to the relayd using URI and send the socket to the right consumer.
623 */
624 static int send_consumer_relayd_socket(int domain, unsigned int session_id,
625 struct lttng_uri *relayd_uri, struct consumer_output *consumer,
626 struct consumer_socket *consumer_sock,
627 char *session_name, char *hostname, int session_live_timer)
628 {
629 int ret;
630 struct lttcomm_relayd_sock *rsock = NULL;
631
632 /* Connect to relayd and make version check if uri is the control. */
633 ret = create_connect_relayd(relayd_uri, &rsock);
634 if (ret != LTTNG_OK) {
635 goto error;
636 }
637 assert(rsock);
638
639 /* Set the network sequence index if not set. */
640 if (consumer->net_seq_index == (uint64_t) -1ULL) {
641 pthread_mutex_lock(&relayd_net_seq_idx_lock);
642 /*
643 * Increment net_seq_idx because we are about to transfer the
644 * new relayd socket to the consumer.
645 * Assign unique key so the consumer can match streams.
646 */
647 consumer->net_seq_index = ++relayd_net_seq_idx;
648 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
649 }
650
651 /* Send relayd socket to consumer. */
652 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
653 relayd_uri->stype, session_id,
654 session_name, hostname, session_live_timer);
655 if (ret < 0) {
656 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
657 goto close_sock;
658 }
659
660 /* Flag that the corresponding socket was sent. */
661 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
662 consumer_sock->control_sock_sent = 1;
663 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
664 consumer_sock->data_sock_sent = 1;
665 }
666
667 ret = LTTNG_OK;
668
669 /*
670 * Close socket which was dup on the consumer side. The session daemon does
671 * NOT keep track of the relayd socket(s) once transfer to the consumer.
672 */
673
674 close_sock:
675 (void) relayd_close(rsock);
676 free(rsock);
677
678 error:
679 if (ret != LTTNG_OK) {
680 /*
681 * The consumer output for this session should not be used anymore
682 * since the relayd connection failed thus making any tracing or/and
683 * streaming not usable.
684 */
685 consumer->enabled = 0;
686 }
687 return ret;
688 }
689
690 /*
691 * Send both relayd sockets to a specific consumer and domain. This is a
692 * helper function to facilitate sending the information to the consumer for a
693 * session.
694 */
695 static int send_consumer_relayd_sockets(int domain, unsigned int session_id,
696 struct consumer_output *consumer, struct consumer_socket *sock,
697 char *session_name, char *hostname, int session_live_timer)
698 {
699 int ret = LTTNG_OK;
700
701 assert(consumer);
702 assert(sock);
703
704 /* Sending control relayd socket. */
705 if (!sock->control_sock_sent) {
706 ret = send_consumer_relayd_socket(domain, session_id,
707 &consumer->dst.net.control, consumer, sock,
708 session_name, hostname, session_live_timer);
709 if (ret != LTTNG_OK) {
710 goto error;
711 }
712 }
713
714 /* Sending data relayd socket. */
715 if (!sock->data_sock_sent) {
716 ret = send_consumer_relayd_socket(domain, session_id,
717 &consumer->dst.net.data, consumer, sock,
718 session_name, hostname, session_live_timer);
719 if (ret != LTTNG_OK) {
720 goto error;
721 }
722 }
723
724 error:
725 return ret;
726 }
727
728 /*
729 * Setup relayd connections for a tracing session. First creates the socket to
730 * the relayd and send them to the right domain consumer. Consumer type MUST be
731 * network.
732 */
733 int cmd_setup_relayd(struct ltt_session *session)
734 {
735 int ret = LTTNG_OK;
736 struct ltt_ust_session *usess;
737 struct ltt_kernel_session *ksess;
738 struct consumer_socket *socket;
739 struct lttng_ht_iter iter;
740
741 assert(session);
742
743 usess = session->ust_session;
744 ksess = session->kernel_session;
745
746 DBG("Setting relayd for session %s", session->name);
747
748 rcu_read_lock();
749
750 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
751 && usess->consumer->enabled) {
752 /* For each consumer socket, send relayd sockets */
753 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
754 socket, node.node) {
755 pthread_mutex_lock(socket->lock);
756 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
757 usess->consumer, socket,
758 session->name, session->hostname,
759 session->live_timer);
760 pthread_mutex_unlock(socket->lock);
761 if (ret != LTTNG_OK) {
762 goto error;
763 }
764 /* Session is now ready for network streaming. */
765 session->net_handle = 1;
766 }
767 }
768
769 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
770 && ksess->consumer->enabled) {
771 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
772 socket, node.node) {
773 pthread_mutex_lock(socket->lock);
774 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
775 ksess->consumer, socket,
776 session->name, session->hostname,
777 session->live_timer);
778 pthread_mutex_unlock(socket->lock);
779 if (ret != LTTNG_OK) {
780 goto error;
781 }
782 /* Session is now ready for network streaming. */
783 session->net_handle = 1;
784 }
785 }
786
787 error:
788 rcu_read_unlock();
789 return ret;
790 }
791
792 /*
793 * Start a kernel session by opening all necessary streams.
794 */
795 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
796 {
797 int ret;
798 struct ltt_kernel_channel *kchan;
799
800 /* Open kernel metadata */
801 if (ksess->metadata == NULL && ksess->output_traces) {
802 ret = kernel_open_metadata(ksess);
803 if (ret < 0) {
804 ret = LTTNG_ERR_KERN_META_FAIL;
805 goto error;
806 }
807 }
808
809 /* Open kernel metadata stream */
810 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
811 ret = kernel_open_metadata_stream(ksess);
812 if (ret < 0) {
813 ERR("Kernel create metadata stream failed");
814 ret = LTTNG_ERR_KERN_STREAM_FAIL;
815 goto error;
816 }
817 }
818
819 /* For each channel */
820 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
821 if (kchan->stream_count == 0) {
822 ret = kernel_open_channel_stream(kchan);
823 if (ret < 0) {
824 ret = LTTNG_ERR_KERN_STREAM_FAIL;
825 goto error;
826 }
827 /* Update the stream global counter */
828 ksess->stream_count_global += ret;
829 }
830 }
831
832 /* Setup kernel consumer socket and send fds to it */
833 ret = init_kernel_tracing(ksess);
834 if (ret != 0) {
835 ret = LTTNG_ERR_KERN_START_FAIL;
836 goto error;
837 }
838
839 /* This start the kernel tracing */
840 ret = kernel_start_session(ksess);
841 if (ret < 0) {
842 ret = LTTNG_ERR_KERN_START_FAIL;
843 goto error;
844 }
845
846 /* Quiescent wait after starting trace */
847 kernel_wait_quiescent(kernel_tracer_fd);
848
849 ksess->active = 1;
850
851 ret = LTTNG_OK;
852
853 error:
854 return ret;
855 }
856
857 /*
858 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
859 */
860 int cmd_disable_channel(struct ltt_session *session, int domain,
861 char *channel_name)
862 {
863 int ret;
864 struct ltt_ust_session *usess;
865
866 usess = session->ust_session;
867
868 rcu_read_lock();
869
870 switch (domain) {
871 case LTTNG_DOMAIN_KERNEL:
872 {
873 ret = channel_kernel_disable(session->kernel_session,
874 channel_name);
875 if (ret != LTTNG_OK) {
876 goto error;
877 }
878
879 kernel_wait_quiescent(kernel_tracer_fd);
880 break;
881 }
882 case LTTNG_DOMAIN_UST:
883 {
884 struct ltt_ust_channel *uchan;
885 struct lttng_ht *chan_ht;
886
887 chan_ht = usess->domain_global.channels;
888
889 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
890 if (uchan == NULL) {
891 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
892 goto error;
893 }
894
895 ret = channel_ust_disable(usess, uchan);
896 if (ret != LTTNG_OK) {
897 goto error;
898 }
899 break;
900 }
901 default:
902 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
903 goto error;
904 }
905
906 ret = LTTNG_OK;
907
908 error:
909 rcu_read_unlock();
910 return ret;
911 }
912
913 /*
914 * Command LTTNG_TRACK_PID processed by the client thread.
915 *
916 * Called with session lock held.
917 */
918 int cmd_track_pid(struct ltt_session *session, int domain, int pid)
919 {
920 int ret;
921
922 rcu_read_lock();
923
924 switch (domain) {
925 case LTTNG_DOMAIN_KERNEL:
926 {
927 struct ltt_kernel_session *ksess;
928
929 ksess = session->kernel_session;
930
931 ret = kernel_track_pid(ksess, pid);
932 if (ret != LTTNG_OK) {
933 goto error;
934 }
935
936 kernel_wait_quiescent(kernel_tracer_fd);
937 break;
938 }
939 case LTTNG_DOMAIN_UST:
940 {
941 struct ltt_ust_session *usess;
942
943 usess = session->ust_session;
944
945 ret = trace_ust_track_pid(usess, pid);
946 if (ret != LTTNG_OK) {
947 goto error;
948 }
949 break;
950 }
951 default:
952 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
953 goto error;
954 }
955
956 ret = LTTNG_OK;
957
958 error:
959 rcu_read_unlock();
960 return ret;
961 }
962
963 /*
964 * Command LTTNG_UNTRACK_PID processed by the client thread.
965 *
966 * Called with session lock held.
967 */
968 int cmd_untrack_pid(struct ltt_session *session, int domain, int pid)
969 {
970 int ret;
971
972 rcu_read_lock();
973
974 switch (domain) {
975 case LTTNG_DOMAIN_KERNEL:
976 {
977 struct ltt_kernel_session *ksess;
978
979 ksess = session->kernel_session;
980
981 ret = kernel_untrack_pid(ksess, pid);
982 if (ret != LTTNG_OK) {
983 goto error;
984 }
985
986 kernel_wait_quiescent(kernel_tracer_fd);
987 break;
988 }
989 case LTTNG_DOMAIN_UST:
990 {
991 struct ltt_ust_session *usess;
992
993 usess = session->ust_session;
994
995 ret = trace_ust_untrack_pid(usess, pid);
996 if (ret != LTTNG_OK) {
997 goto error;
998 }
999 break;
1000 }
1001 default:
1002 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1003 goto error;
1004 }
1005
1006 ret = LTTNG_OK;
1007
1008 error:
1009 rcu_read_unlock();
1010 return ret;
1011 }
1012
1013 /*
1014 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1015 *
1016 * The wpipe arguments is used as a notifier for the kernel thread.
1017 */
1018 int cmd_enable_channel(struct ltt_session *session,
1019 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1020 {
1021 int ret;
1022 struct ltt_ust_session *usess = session->ust_session;
1023 struct lttng_ht *chan_ht;
1024 size_t len;
1025
1026 assert(session);
1027 assert(attr);
1028 assert(domain);
1029
1030 len = strnlen(attr->name, sizeof(attr->name));
1031
1032 /* Validate channel name */
1033 if (attr->name[0] == '.' ||
1034 memchr(attr->name, '/', len) != NULL) {
1035 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1036 goto end;
1037 }
1038
1039 DBG("Enabling channel %s for session %s", attr->name, session->name);
1040
1041 rcu_read_lock();
1042
1043 /*
1044 * Don't try to enable a channel if the session has been started at
1045 * some point in time before. The tracer does not allow it.
1046 */
1047 if (session->has_been_started) {
1048 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1049 goto error;
1050 }
1051
1052 /*
1053 * If the session is a live session, remove the switch timer, the
1054 * live timer does the same thing but sends also synchronisation
1055 * beacons for inactive streams.
1056 */
1057 if (session->live_timer > 0) {
1058 attr->attr.live_timer_interval = session->live_timer;
1059 attr->attr.switch_timer_interval = 0;
1060 }
1061
1062 /*
1063 * The ringbuffer (both in user space and kernel) behave badly in overwrite
1064 * mode and with less than 2 subbuf so block it right away and send back an
1065 * invalid attribute error.
1066 */
1067 if (attr->attr.overwrite && attr->attr.num_subbuf < 2) {
1068 ret = LTTNG_ERR_INVALID;
1069 goto error;
1070 }
1071
1072 switch (domain->type) {
1073 case LTTNG_DOMAIN_KERNEL:
1074 {
1075 struct ltt_kernel_channel *kchan;
1076
1077 kchan = trace_kernel_get_channel_by_name(attr->name,
1078 session->kernel_session);
1079 if (kchan == NULL) {
1080 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1081 if (attr->name[0] != '\0') {
1082 session->kernel_session->has_non_default_channel = 1;
1083 }
1084 } else {
1085 ret = channel_kernel_enable(session->kernel_session, kchan);
1086 }
1087
1088 if (ret != LTTNG_OK) {
1089 goto error;
1090 }
1091
1092 kernel_wait_quiescent(kernel_tracer_fd);
1093 break;
1094 }
1095 case LTTNG_DOMAIN_UST:
1096 {
1097 struct ltt_ust_channel *uchan;
1098
1099 chan_ht = usess->domain_global.channels;
1100
1101 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1102 if (uchan == NULL) {
1103 ret = channel_ust_create(usess, attr, domain->buf_type);
1104 if (attr->name[0] != '\0') {
1105 usess->has_non_default_channel = 1;
1106 }
1107 } else {
1108 ret = channel_ust_enable(usess, uchan);
1109 }
1110 break;
1111 }
1112 default:
1113 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1114 goto error;
1115 }
1116
1117 error:
1118 rcu_read_unlock();
1119 end:
1120 return ret;
1121 }
1122
1123 /*
1124 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1125 */
1126 int cmd_disable_event(struct ltt_session *session, int domain,
1127 char *channel_name,
1128 struct lttng_event *event)
1129 {
1130 int ret;
1131 char *event_name;
1132
1133 DBG("Disable event command for event \'%s\'", event->name);
1134
1135 event_name = event->name;
1136
1137 /* Error out on unhandled search criteria */
1138 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1139 || event->pid || event->filter || event->exclusion) {
1140 return LTTNG_ERR_UNK;
1141 }
1142
1143 rcu_read_lock();
1144
1145 switch (domain) {
1146 case LTTNG_DOMAIN_KERNEL:
1147 {
1148 struct ltt_kernel_channel *kchan;
1149 struct ltt_kernel_session *ksess;
1150
1151 ksess = session->kernel_session;
1152
1153 /*
1154 * If a non-default channel has been created in the
1155 * session, explicitely require that -c chan_name needs
1156 * to be provided.
1157 */
1158 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1159 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1160 goto error;
1161 }
1162
1163 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1164 if (kchan == NULL) {
1165 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1166 goto error;
1167 }
1168
1169 switch (event->type) {
1170 case LTTNG_EVENT_ALL:
1171 ret = event_kernel_disable_event_all(kchan);
1172 if (ret != LTTNG_OK) {
1173 goto error;
1174 }
1175 break;
1176 case LTTNG_EVENT_TRACEPOINT: /* fall-through */
1177 case LTTNG_EVENT_SYSCALL:
1178 if (!strcmp(event_name, "*")) {
1179 ret = event_kernel_disable_event_type(kchan,
1180 event->type);
1181 } else {
1182 ret = event_kernel_disable_event(kchan,
1183 event_name);
1184 }
1185 if (ret != LTTNG_OK) {
1186 goto error;
1187 }
1188 break;
1189 case LTTNG_EVENT_PROBE:
1190 case LTTNG_EVENT_FUNCTION:
1191 case LTTNG_EVENT_FUNCTION_ENTRY:
1192 ret = event_kernel_disable_event(kchan, event_name);
1193 if (ret != LTTNG_OK) {
1194 goto error;
1195 }
1196 break;
1197 default:
1198 ret = LTTNG_ERR_UNK;
1199 goto error;
1200 }
1201
1202 kernel_wait_quiescent(kernel_tracer_fd);
1203 break;
1204 }
1205 case LTTNG_DOMAIN_UST:
1206 {
1207 struct ltt_ust_channel *uchan;
1208 struct ltt_ust_session *usess;
1209
1210 usess = session->ust_session;
1211
1212 /*
1213 * If a non-default channel has been created in the
1214 * session, explicitely require that -c chan_name needs
1215 * to be provided.
1216 */
1217 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1218 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1219 goto error;
1220 }
1221
1222 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1223 channel_name);
1224 if (uchan == NULL) {
1225 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1226 goto error;
1227 }
1228
1229 switch (event->type) {
1230 case LTTNG_EVENT_ALL:
1231 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
1232 if (ret != LTTNG_OK) {
1233 goto error;
1234 }
1235 break;
1236 default:
1237 ret = LTTNG_ERR_UNK;
1238 goto error;
1239 }
1240
1241 DBG3("Disable UST event %s in channel %s completed", event_name,
1242 channel_name);
1243 break;
1244 }
1245 case LTTNG_DOMAIN_LOG4J:
1246 case LTTNG_DOMAIN_JUL:
1247 case LTTNG_DOMAIN_PYTHON:
1248 {
1249 struct agent *agt;
1250 struct ltt_ust_session *usess = session->ust_session;
1251
1252 assert(usess);
1253
1254 switch (event->type) {
1255 case LTTNG_EVENT_ALL:
1256 break;
1257 default:
1258 ret = LTTNG_ERR_UNK;
1259 goto error;
1260 }
1261
1262 agt = trace_ust_find_agent(usess, domain);
1263 if (!agt) {
1264 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1265 goto error;
1266 }
1267 /* The wild card * means that everything should be disabled. */
1268 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1269 ret = event_agent_disable_all(usess, agt);
1270 } else {
1271 ret = event_agent_disable(usess, agt, event_name);
1272 }
1273 if (ret != LTTNG_OK) {
1274 goto error;
1275 }
1276
1277 break;
1278 }
1279 default:
1280 ret = LTTNG_ERR_UND;
1281 goto error;
1282 }
1283
1284 ret = LTTNG_OK;
1285
1286 error:
1287 rcu_read_unlock();
1288 return ret;
1289 }
1290
1291 /*
1292 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1293 */
1294 int cmd_add_context(struct ltt_session *session, int domain,
1295 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1296 {
1297 int ret, chan_kern_created = 0, chan_ust_created = 0;
1298
1299 switch (domain) {
1300 case LTTNG_DOMAIN_KERNEL:
1301 assert(session->kernel_session);
1302
1303 if (session->kernel_session->channel_count == 0) {
1304 /* Create default channel */
1305 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1306 if (ret != LTTNG_OK) {
1307 goto error;
1308 }
1309 chan_kern_created = 1;
1310 }
1311 /* Add kernel context to kernel tracer */
1312 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1313 if (ret != LTTNG_OK) {
1314 goto error;
1315 }
1316 break;
1317 case LTTNG_DOMAIN_UST:
1318 {
1319 struct ltt_ust_session *usess = session->ust_session;
1320 unsigned int chan_count;
1321
1322 assert(usess);
1323
1324 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1325 if (chan_count == 0) {
1326 struct lttng_channel *attr;
1327 /* Create default channel */
1328 attr = channel_new_default_attr(domain, usess->buffer_type);
1329 if (attr == NULL) {
1330 ret = LTTNG_ERR_FATAL;
1331 goto error;
1332 }
1333
1334 ret = channel_ust_create(usess, attr, usess->buffer_type);
1335 if (ret != LTTNG_OK) {
1336 free(attr);
1337 goto error;
1338 }
1339 free(attr);
1340 chan_ust_created = 1;
1341 }
1342
1343 ret = context_ust_add(usess, domain, ctx, channel_name);
1344 if (ret != LTTNG_OK) {
1345 goto error;
1346 }
1347 break;
1348 }
1349 default:
1350 ret = LTTNG_ERR_UND;
1351 goto error;
1352 }
1353
1354 return LTTNG_OK;
1355
1356 error:
1357 if (chan_kern_created) {
1358 struct ltt_kernel_channel *kchan =
1359 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1360 session->kernel_session);
1361 /* Created previously, this should NOT fail. */
1362 assert(kchan);
1363 kernel_destroy_channel(kchan);
1364 }
1365
1366 if (chan_ust_created) {
1367 struct ltt_ust_channel *uchan =
1368 trace_ust_find_channel_by_name(
1369 session->ust_session->domain_global.channels,
1370 DEFAULT_CHANNEL_NAME);
1371 /* Created previously, this should NOT fail. */
1372 assert(uchan);
1373 /* Remove from the channel list of the session. */
1374 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1375 uchan);
1376 trace_ust_destroy_channel(uchan);
1377 }
1378 return ret;
1379 }
1380
1381 static int validate_event_name(const char *name)
1382 {
1383 int ret = 0;
1384 const char *c = name;
1385 const char *event_name_end = c + LTTNG_SYMBOL_NAME_LEN;
1386 bool null_terminated = false;
1387
1388 /*
1389 * Make sure that unescaped wildcards are only used as the last
1390 * character of the event name.
1391 */
1392 while (c < event_name_end) {
1393 switch (*c) {
1394 case '\0':
1395 null_terminated = true;
1396 goto end;
1397 case '\\':
1398 c++;
1399 break;
1400 case '*':
1401 if ((c + 1) < event_name_end && *(c + 1)) {
1402 /* Wildcard is not the last character */
1403 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1404 goto end;
1405 }
1406 default:
1407 break;
1408 }
1409 c++;
1410 }
1411 end:
1412 if (!ret && !null_terminated) {
1413 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1414 }
1415 return ret;
1416 }
1417
1418 /*
1419 * Command LTTNG_ENABLE_EVENT processed by the client thread.
1420 * We own filter, exclusion, and filter_expression.
1421 */
1422 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1423 char *channel_name, struct lttng_event *event,
1424 char *filter_expression,
1425 struct lttng_filter_bytecode *filter,
1426 struct lttng_event_exclusion *exclusion,
1427 int wpipe)
1428 {
1429 int ret, channel_created = 0;
1430 struct lttng_channel *attr;
1431
1432 assert(session);
1433 assert(event);
1434 assert(channel_name);
1435
1436 DBG("Enable event command for event \'%s\'", event->name);
1437
1438 ret = validate_event_name(event->name);
1439 if (ret) {
1440 goto error;
1441 }
1442
1443 rcu_read_lock();
1444
1445 switch (domain->type) {
1446 case LTTNG_DOMAIN_KERNEL:
1447 {
1448 struct ltt_kernel_channel *kchan;
1449
1450 /*
1451 * If a non-default channel has been created in the
1452 * session, explicitely require that -c chan_name needs
1453 * to be provided.
1454 */
1455 if (session->kernel_session->has_non_default_channel
1456 && channel_name[0] == '\0') {
1457 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1458 goto error;
1459 }
1460
1461 kchan = trace_kernel_get_channel_by_name(channel_name,
1462 session->kernel_session);
1463 if (kchan == NULL) {
1464 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1465 LTTNG_BUFFER_GLOBAL);
1466 if (attr == NULL) {
1467 ret = LTTNG_ERR_FATAL;
1468 goto error;
1469 }
1470 strncpy(attr->name, channel_name, sizeof(attr->name));
1471
1472 ret = cmd_enable_channel(session, domain, attr, wpipe);
1473 if (ret != LTTNG_OK) {
1474 free(attr);
1475 goto error;
1476 }
1477 free(attr);
1478
1479 channel_created = 1;
1480 }
1481
1482 /* Get the newly created kernel channel pointer */
1483 kchan = trace_kernel_get_channel_by_name(channel_name,
1484 session->kernel_session);
1485 if (kchan == NULL) {
1486 /* This sould not happen... */
1487 ret = LTTNG_ERR_FATAL;
1488 goto error;
1489 }
1490
1491 switch (event->type) {
1492 case LTTNG_EVENT_ALL:
1493 {
1494 char *filter_expression_a = NULL;
1495 struct lttng_filter_bytecode *filter_a = NULL;
1496
1497 /*
1498 * We need to duplicate filter_expression and filter,
1499 * because ownership is passed to first enable
1500 * event.
1501 */
1502 if (filter_expression) {
1503 filter_expression_a = strdup(filter_expression);
1504 if (!filter_expression_a) {
1505 ret = LTTNG_ERR_FATAL;
1506 goto error;
1507 }
1508 }
1509 if (filter) {
1510 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
1511 if (!filter_a) {
1512 free(filter_expression_a);
1513 ret = LTTNG_ERR_FATAL;
1514 goto error;
1515 }
1516 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
1517 }
1518 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
1519 ret = event_kernel_enable_event(kchan, event,
1520 filter_expression, filter);
1521 /* We have passed ownership */
1522 filter_expression = NULL;
1523 filter = NULL;
1524 if (ret != LTTNG_OK) {
1525 if (channel_created) {
1526 /* Let's not leak a useless channel. */
1527 kernel_destroy_channel(kchan);
1528 }
1529 free(filter_expression_a);
1530 free(filter_a);
1531 goto error;
1532 }
1533 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
1534 ret = event_kernel_enable_event(kchan, event,
1535 filter_expression_a, filter_a);
1536 if (ret != LTTNG_OK) {
1537 free(filter_expression_a);
1538 free(filter_a);
1539 goto error;
1540 }
1541 break;
1542 }
1543 case LTTNG_EVENT_PROBE:
1544 case LTTNG_EVENT_FUNCTION:
1545 case LTTNG_EVENT_FUNCTION_ENTRY:
1546 case LTTNG_EVENT_TRACEPOINT:
1547 ret = event_kernel_enable_event(kchan, event,
1548 filter_expression, filter);
1549 /* We have passed ownership */
1550 filter_expression = NULL;
1551 filter = NULL;
1552 if (ret != LTTNG_OK) {
1553 if (channel_created) {
1554 /* Let's not leak a useless channel. */
1555 kernel_destroy_channel(kchan);
1556 }
1557 goto error;
1558 }
1559 break;
1560 case LTTNG_EVENT_SYSCALL:
1561 ret = event_kernel_enable_event(kchan, event,
1562 filter_expression, filter);
1563 /* We have passed ownership */
1564 filter_expression = NULL;
1565 filter = NULL;
1566 if (ret != LTTNG_OK) {
1567 goto error;
1568 }
1569 break;
1570 default:
1571 ret = LTTNG_ERR_UNK;
1572 goto error;
1573 }
1574
1575 kernel_wait_quiescent(kernel_tracer_fd);
1576 break;
1577 }
1578 case LTTNG_DOMAIN_UST:
1579 {
1580 struct ltt_ust_channel *uchan;
1581 struct ltt_ust_session *usess = session->ust_session;
1582
1583 assert(usess);
1584
1585 /*
1586 * If a non-default channel has been created in the
1587 * session, explicitely require that -c chan_name needs
1588 * to be provided.
1589 */
1590 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1591 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1592 goto error;
1593 }
1594
1595 /* Get channel from global UST domain */
1596 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1597 channel_name);
1598 if (uchan == NULL) {
1599 /* Create default channel */
1600 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1601 usess->buffer_type);
1602 if (attr == NULL) {
1603 ret = LTTNG_ERR_FATAL;
1604 goto error;
1605 }
1606 strncpy(attr->name, channel_name, sizeof(attr->name));
1607
1608 ret = cmd_enable_channel(session, domain, attr, wpipe);
1609 if (ret != LTTNG_OK) {
1610 free(attr);
1611 goto error;
1612 }
1613 free(attr);
1614
1615 /* Get the newly created channel reference back */
1616 uchan = trace_ust_find_channel_by_name(
1617 usess->domain_global.channels, channel_name);
1618 assert(uchan);
1619 }
1620
1621 /* At this point, the session and channel exist on the tracer */
1622 ret = event_ust_enable_tracepoint(usess, uchan, event,
1623 filter_expression, filter, exclusion);
1624 /* We have passed ownership */
1625 filter_expression = NULL;
1626 filter = NULL;
1627 exclusion = NULL;
1628 if (ret != LTTNG_OK) {
1629 goto error;
1630 }
1631 break;
1632 }
1633 case LTTNG_DOMAIN_LOG4J:
1634 case LTTNG_DOMAIN_JUL:
1635 case LTTNG_DOMAIN_PYTHON:
1636 {
1637 const char *default_event_name, *default_chan_name;
1638 struct agent *agt;
1639 struct lttng_event uevent;
1640 struct lttng_domain tmp_dom;
1641 struct ltt_ust_session *usess = session->ust_session;
1642
1643 assert(usess);
1644
1645 agt = trace_ust_find_agent(usess, domain->type);
1646 if (!agt) {
1647 agt = agent_create(domain->type);
1648 if (!agt) {
1649 ret = -LTTNG_ERR_NOMEM;
1650 goto error;
1651 }
1652 agent_add(agt, usess->agents);
1653 }
1654
1655 /* Create the default tracepoint. */
1656 memset(&uevent, 0, sizeof(uevent));
1657 uevent.type = LTTNG_EVENT_TRACEPOINT;
1658 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
1659 default_event_name = event_get_default_agent_ust_name(domain->type);
1660 if (!default_event_name) {
1661 ret = -LTTNG_ERR_FATAL;
1662 goto error;
1663 }
1664 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
1665 uevent.name[sizeof(uevent.name) - 1] = '\0';
1666
1667 /*
1668 * The domain type is changed because we are about to enable the
1669 * default channel and event for the JUL domain that are hardcoded.
1670 * This happens in the UST domain.
1671 */
1672 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
1673 tmp_dom.type = LTTNG_DOMAIN_UST;
1674
1675 switch (domain->type) {
1676 case LTTNG_DOMAIN_LOG4J:
1677 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
1678 break;
1679 case LTTNG_DOMAIN_JUL:
1680 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
1681 break;
1682 case LTTNG_DOMAIN_PYTHON:
1683 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
1684 break;
1685 default:
1686 /* The switch/case we are in should avoid this else big problem */
1687 assert(0);
1688 }
1689
1690 {
1691 struct lttng_filter_bytecode *filter_copy = NULL;
1692
1693 if (filter) {
1694 filter_copy = zmalloc(
1695 sizeof(struct lttng_filter_bytecode)
1696 + filter->len);
1697 if (!filter_copy) {
1698 goto error;
1699 }
1700
1701 memcpy(filter_copy, filter,
1702 sizeof(struct lttng_filter_bytecode)
1703 + filter->len);
1704 }
1705
1706 ret = cmd_enable_event(session, &tmp_dom,
1707 (char *) default_chan_name,
1708 &uevent, filter_expression, filter_copy,
1709 NULL, wpipe);
1710 /* We have passed ownership */
1711 filter_expression = NULL;
1712 }
1713
1714 if (ret != LTTNG_OK && ret != LTTNG_ERR_UST_EVENT_ENABLED) {
1715 goto error;
1716 }
1717
1718 /* The wild card * means that everything should be enabled. */
1719 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1720 ret = event_agent_enable_all(usess, agt, event, filter);
1721 filter = NULL;
1722 } else {
1723 ret = event_agent_enable(usess, agt, event, filter);
1724 filter = NULL;
1725 }
1726 if (ret != LTTNG_OK) {
1727 goto error;
1728 }
1729
1730 break;
1731 }
1732 default:
1733 ret = LTTNG_ERR_UND;
1734 goto error;
1735 }
1736
1737 ret = LTTNG_OK;
1738
1739 error:
1740 free(filter_expression);
1741 free(filter);
1742 free(exclusion);
1743 rcu_read_unlock();
1744 return ret;
1745 }
1746
1747 /*
1748 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1749 */
1750 ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
1751 {
1752 int ret;
1753 ssize_t nb_events = 0;
1754
1755 switch (domain) {
1756 case LTTNG_DOMAIN_KERNEL:
1757 nb_events = kernel_list_events(kernel_tracer_fd, events);
1758 if (nb_events < 0) {
1759 ret = LTTNG_ERR_KERN_LIST_FAIL;
1760 goto error;
1761 }
1762 break;
1763 case LTTNG_DOMAIN_UST:
1764 nb_events = ust_app_list_events(events);
1765 if (nb_events < 0) {
1766 ret = LTTNG_ERR_UST_LIST_FAIL;
1767 goto error;
1768 }
1769 break;
1770 case LTTNG_DOMAIN_LOG4J:
1771 case LTTNG_DOMAIN_JUL:
1772 case LTTNG_DOMAIN_PYTHON:
1773 nb_events = agent_list_events(events, domain);
1774 if (nb_events < 0) {
1775 ret = LTTNG_ERR_UST_LIST_FAIL;
1776 goto error;
1777 }
1778 break;
1779 default:
1780 ret = LTTNG_ERR_UND;
1781 goto error;
1782 }
1783
1784 return nb_events;
1785
1786 error:
1787 /* Return negative value to differentiate return code */
1788 return -ret;
1789 }
1790
1791 /*
1792 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1793 */
1794 ssize_t cmd_list_tracepoint_fields(int domain,
1795 struct lttng_event_field **fields)
1796 {
1797 int ret;
1798 ssize_t nb_fields = 0;
1799
1800 switch (domain) {
1801 case LTTNG_DOMAIN_UST:
1802 nb_fields = ust_app_list_event_fields(fields);
1803 if (nb_fields < 0) {
1804 ret = LTTNG_ERR_UST_LIST_FAIL;
1805 goto error;
1806 }
1807 break;
1808 case LTTNG_DOMAIN_KERNEL:
1809 default: /* fall-through */
1810 ret = LTTNG_ERR_UND;
1811 goto error;
1812 }
1813
1814 return nb_fields;
1815
1816 error:
1817 /* Return negative value to differentiate return code */
1818 return -ret;
1819 }
1820
1821 ssize_t cmd_list_syscalls(struct lttng_event **events)
1822 {
1823 return syscall_table_list(events);
1824 }
1825
1826 /*
1827 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
1828 *
1829 * Called with session lock held.
1830 */
1831 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
1832 int domain, int32_t **pids)
1833 {
1834 int ret;
1835 ssize_t nr_pids = 0;
1836
1837 switch (domain) {
1838 case LTTNG_DOMAIN_KERNEL:
1839 {
1840 struct ltt_kernel_session *ksess;
1841
1842 ksess = session->kernel_session;
1843 nr_pids = kernel_list_tracker_pids(ksess, pids);
1844 if (nr_pids < 0) {
1845 ret = LTTNG_ERR_KERN_LIST_FAIL;
1846 goto error;
1847 }
1848 break;
1849 }
1850 case LTTNG_DOMAIN_UST:
1851 {
1852 struct ltt_ust_session *usess;
1853
1854 usess = session->ust_session;
1855 nr_pids = trace_ust_list_tracker_pids(usess, pids);
1856 if (nr_pids < 0) {
1857 ret = LTTNG_ERR_UST_LIST_FAIL;
1858 goto error;
1859 }
1860 break;
1861 }
1862 case LTTNG_DOMAIN_LOG4J:
1863 case LTTNG_DOMAIN_JUL:
1864 case LTTNG_DOMAIN_PYTHON:
1865 default:
1866 ret = LTTNG_ERR_UND;
1867 goto error;
1868 }
1869
1870 return nr_pids;
1871
1872 error:
1873 /* Return negative value to differentiate return code */
1874 return -ret;
1875 }
1876
1877 /*
1878 * Command LTTNG_START_TRACE processed by the client thread.
1879 *
1880 * Called with session mutex held.
1881 */
1882 int cmd_start_trace(struct ltt_session *session)
1883 {
1884 int ret;
1885 unsigned long nb_chan = 0;
1886 struct ltt_kernel_session *ksession;
1887 struct ltt_ust_session *usess;
1888
1889 assert(session);
1890
1891 /* Ease our life a bit ;) */
1892 ksession = session->kernel_session;
1893 usess = session->ust_session;
1894
1895 /* Is the session already started? */
1896 if (session->active) {
1897 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1898 goto error;
1899 }
1900
1901 /*
1902 * Starting a session without channel is useless since after that it's not
1903 * possible to enable channel thus inform the client.
1904 */
1905 if (usess && usess->domain_global.channels) {
1906 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
1907 }
1908 if (ksession) {
1909 nb_chan += ksession->channel_count;
1910 }
1911 if (!nb_chan) {
1912 ret = LTTNG_ERR_NO_CHANNEL;
1913 goto error;
1914 }
1915
1916 /* Kernel tracing */
1917 if (ksession != NULL) {
1918 ret = start_kernel_session(ksession, kernel_tracer_fd);
1919 if (ret != LTTNG_OK) {
1920 goto error;
1921 }
1922 }
1923
1924 /* Flag session that trace should start automatically */
1925 if (usess) {
1926 /*
1927 * Even though the start trace might fail, flag this session active so
1928 * other application coming in are started by default.
1929 */
1930 usess->active = 1;
1931
1932 ret = ust_app_start_trace_all(usess);
1933 if (ret < 0) {
1934 ret = LTTNG_ERR_UST_START_FAIL;
1935 goto error;
1936 }
1937 }
1938
1939 /* Flag this after a successful start. */
1940 session->has_been_started = 1;
1941 session->active = 1;
1942
1943 ret = LTTNG_OK;
1944
1945 error:
1946 return ret;
1947 }
1948
1949 /*
1950 * Command LTTNG_STOP_TRACE processed by the client thread.
1951 */
1952 int cmd_stop_trace(struct ltt_session *session)
1953 {
1954 int ret;
1955 struct ltt_kernel_channel *kchan;
1956 struct ltt_kernel_session *ksession;
1957 struct ltt_ust_session *usess;
1958
1959 assert(session);
1960
1961 /* Short cut */
1962 ksession = session->kernel_session;
1963 usess = session->ust_session;
1964
1965 /* Session is not active. Skip everythong and inform the client. */
1966 if (!session->active) {
1967 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
1968 goto error;
1969 }
1970
1971 /* Kernel tracer */
1972 if (ksession && ksession->active) {
1973 DBG("Stop kernel tracing");
1974
1975 /* Flush metadata if exist */
1976 if (ksession->metadata_stream_fd >= 0) {
1977 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
1978 if (ret < 0) {
1979 ERR("Kernel metadata flush failed");
1980 }
1981 }
1982
1983 /* Flush all buffers before stopping */
1984 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
1985 ret = kernel_flush_buffer(kchan);
1986 if (ret < 0) {
1987 ERR("Kernel flush buffer error");
1988 }
1989 }
1990
1991 ret = kernel_stop_session(ksession);
1992 if (ret < 0) {
1993 ret = LTTNG_ERR_KERN_STOP_FAIL;
1994 goto error;
1995 }
1996
1997 kernel_wait_quiescent(kernel_tracer_fd);
1998
1999 ksession->active = 0;
2000 }
2001
2002 if (usess && usess->active) {
2003 /*
2004 * Even though the stop trace might fail, flag this session inactive so
2005 * other application coming in are not started by default.
2006 */
2007 usess->active = 0;
2008
2009 ret = ust_app_stop_trace_all(usess);
2010 if (ret < 0) {
2011 ret = LTTNG_ERR_UST_STOP_FAIL;
2012 goto error;
2013 }
2014 }
2015
2016 /* Flag inactive after a successful stop. */
2017 session->active = 0;
2018 ret = LTTNG_OK;
2019
2020 error:
2021 return ret;
2022 }
2023
2024 /*
2025 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2026 */
2027 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2028 struct lttng_uri *uris)
2029 {
2030 int ret, i;
2031 struct ltt_kernel_session *ksess = session->kernel_session;
2032 struct ltt_ust_session *usess = session->ust_session;
2033
2034 assert(session);
2035 assert(uris);
2036 assert(nb_uri > 0);
2037
2038 /* Can't set consumer URI if the session is active. */
2039 if (session->active) {
2040 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2041 goto error;
2042 }
2043
2044 /* Set the "global" consumer URIs */
2045 for (i = 0; i < nb_uri; i++) {
2046 ret = add_uri_to_consumer(session->consumer,
2047 &uris[i], 0, session->name);
2048 if (ret != LTTNG_OK) {
2049 goto error;
2050 }
2051 }
2052
2053 /* Set UST session URIs */
2054 if (session->ust_session) {
2055 for (i = 0; i < nb_uri; i++) {
2056 ret = add_uri_to_consumer(
2057 session->ust_session->consumer,
2058 &uris[i], LTTNG_DOMAIN_UST,
2059 session->name);
2060 if (ret != LTTNG_OK) {
2061 goto error;
2062 }
2063 }
2064 }
2065
2066 /* Set kernel session URIs */
2067 if (session->kernel_session) {
2068 for (i = 0; i < nb_uri; i++) {
2069 ret = add_uri_to_consumer(
2070 session->kernel_session->consumer,
2071 &uris[i], LTTNG_DOMAIN_KERNEL,
2072 session->name);
2073 if (ret != LTTNG_OK) {
2074 goto error;
2075 }
2076 }
2077 }
2078
2079 /*
2080 * Make sure to set the session in output mode after we set URI since a
2081 * session can be created without URL (thus flagged in no output mode).
2082 */
2083 session->output_traces = 1;
2084 if (ksess) {
2085 ksess->output_traces = 1;
2086 }
2087
2088 if (usess) {
2089 usess->output_traces = 1;
2090 }
2091
2092 /* All good! */
2093 ret = LTTNG_OK;
2094
2095 error:
2096 return ret;
2097 }
2098
2099 /*
2100 * Command LTTNG_CREATE_SESSION processed by the client thread.
2101 */
2102 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
2103 size_t nb_uri, lttng_sock_cred *creds, unsigned int live_timer)
2104 {
2105 int ret;
2106 struct ltt_session *session;
2107
2108 assert(name);
2109 assert(creds);
2110
2111 /*
2112 * Verify if the session already exist
2113 *
2114 * XXX: There is no need for the session lock list here since the caller
2115 * (process_client_msg) is holding it. We might want to change that so a
2116 * single command does not lock the entire session list.
2117 */
2118 session = session_find_by_name(name);
2119 if (session != NULL) {
2120 ret = LTTNG_ERR_EXIST_SESS;
2121 goto find_error;
2122 }
2123
2124 /* Create tracing session in the registry */
2125 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
2126 LTTNG_SOCK_GET_GID_CRED(creds));
2127 if (ret != LTTNG_OK) {
2128 goto session_error;
2129 }
2130
2131 /*
2132 * Get the newly created session pointer back
2133 *
2134 * XXX: There is no need for the session lock list here since the caller
2135 * (process_client_msg) is holding it. We might want to change that so a
2136 * single command does not lock the entire session list.
2137 */
2138 session = session_find_by_name(name);
2139 assert(session);
2140
2141 session->live_timer = live_timer;
2142 /* Create default consumer output for the session not yet created. */
2143 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
2144 if (session->consumer == NULL) {
2145 ret = LTTNG_ERR_FATAL;
2146 goto consumer_error;
2147 }
2148
2149 if (uris) {
2150 ret = cmd_set_consumer_uri(session, nb_uri, uris);
2151 if (ret != LTTNG_OK) {
2152 goto consumer_error;
2153 }
2154 session->output_traces = 1;
2155 } else {
2156 session->output_traces = 0;
2157 DBG2("Session %s created with no output", session->name);
2158 }
2159
2160 session->consumer->enabled = 1;
2161
2162 return LTTNG_OK;
2163
2164 consumer_error:
2165 session_destroy(session);
2166 session_error:
2167 find_error:
2168 return ret;
2169 }
2170
2171 /*
2172 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
2173 */
2174 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
2175 size_t nb_uri, lttng_sock_cred *creds)
2176 {
2177 int ret;
2178 struct ltt_session *session;
2179 struct snapshot_output *new_output = NULL;
2180
2181 assert(name);
2182 assert(creds);
2183
2184 /*
2185 * Create session in no output mode with URIs set to NULL. The uris we've
2186 * received are for a default snapshot output if one.
2187 */
2188 ret = cmd_create_session_uri(name, NULL, 0, creds, -1);
2189 if (ret != LTTNG_OK) {
2190 goto error;
2191 }
2192
2193 /* Get the newly created session pointer back. This should NEVER fail. */
2194 session = session_find_by_name(name);
2195 assert(session);
2196
2197 /* Flag session for snapshot mode. */
2198 session->snapshot_mode = 1;
2199
2200 /* Skip snapshot output creation if no URI is given. */
2201 if (nb_uri == 0) {
2202 goto end;
2203 }
2204
2205 new_output = snapshot_output_alloc();
2206 if (!new_output) {
2207 ret = LTTNG_ERR_NOMEM;
2208 goto error_snapshot_alloc;
2209 }
2210
2211 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
2212 uris, nb_uri, session->consumer, new_output, &session->snapshot);
2213 if (ret < 0) {
2214 if (ret == -ENOMEM) {
2215 ret = LTTNG_ERR_NOMEM;
2216 } else {
2217 ret = LTTNG_ERR_INVALID;
2218 }
2219 goto error_snapshot;
2220 }
2221
2222 rcu_read_lock();
2223 snapshot_add_output(&session->snapshot, new_output);
2224 rcu_read_unlock();
2225
2226 end:
2227 return LTTNG_OK;
2228
2229 error_snapshot:
2230 snapshot_output_destroy(new_output);
2231 error_snapshot_alloc:
2232 session_destroy(session);
2233 error:
2234 return ret;
2235 }
2236
2237 /*
2238 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2239 *
2240 * Called with session lock held.
2241 */
2242 int cmd_destroy_session(struct ltt_session *session, int wpipe)
2243 {
2244 int ret;
2245 struct ltt_ust_session *usess;
2246 struct ltt_kernel_session *ksess;
2247
2248 /* Safety net */
2249 assert(session);
2250
2251 usess = session->ust_session;
2252 ksess = session->kernel_session;
2253
2254 /* Clean kernel session teardown */
2255 kernel_destroy_session(ksess);
2256
2257 /* UST session teardown */
2258 if (usess) {
2259 /* Close any relayd session */
2260 consumer_output_send_destroy_relayd(usess->consumer);
2261
2262 /* Destroy every UST application related to this session. */
2263 ret = ust_app_destroy_trace_all(usess);
2264 if (ret) {
2265 ERR("Error in ust_app_destroy_trace_all");
2266 }
2267
2268 /* Clean up the rest. */
2269 trace_ust_destroy_session(usess);
2270 }
2271
2272 /*
2273 * Must notify the kernel thread here to update it's poll set in order to
2274 * remove the channel(s)' fd just destroyed.
2275 */
2276 ret = notify_thread_pipe(wpipe);
2277 if (ret < 0) {
2278 PERROR("write kernel poll pipe");
2279 }
2280
2281 ret = session_destroy(session);
2282
2283 return ret;
2284 }
2285
2286 /*
2287 * Command LTTNG_CALIBRATE processed by the client thread.
2288 */
2289 int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2290 {
2291 int ret;
2292
2293 switch (domain) {
2294 case LTTNG_DOMAIN_KERNEL:
2295 {
2296 struct lttng_kernel_calibrate kcalibrate;
2297
2298 switch (calibrate->type) {
2299 case LTTNG_CALIBRATE_FUNCTION:
2300 default:
2301 /* Default and only possible calibrate option. */
2302 kcalibrate.type = LTTNG_KERNEL_CALIBRATE_KRETPROBE;
2303 break;
2304 }
2305
2306 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2307 if (ret < 0) {
2308 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
2309 goto error;
2310 }
2311 break;
2312 }
2313 case LTTNG_DOMAIN_UST:
2314 {
2315 struct lttng_ust_calibrate ucalibrate;
2316
2317 switch (calibrate->type) {
2318 case LTTNG_CALIBRATE_FUNCTION:
2319 default:
2320 /* Default and only possible calibrate option. */
2321 ucalibrate.type = LTTNG_UST_CALIBRATE_TRACEPOINT;
2322 break;
2323 }
2324
2325 ret = ust_app_calibrate_glb(&ucalibrate);
2326 if (ret < 0) {
2327 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
2328 goto error;
2329 }
2330 break;
2331 }
2332 default:
2333 ret = LTTNG_ERR_UND;
2334 goto error;
2335 }
2336
2337 ret = LTTNG_OK;
2338
2339 error:
2340 return ret;
2341 }
2342
2343 /*
2344 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2345 */
2346 int cmd_register_consumer(struct ltt_session *session, int domain,
2347 const char *sock_path, struct consumer_data *cdata)
2348 {
2349 int ret, sock;
2350 struct consumer_socket *socket = NULL;
2351
2352 assert(session);
2353 assert(cdata);
2354 assert(sock_path);
2355
2356 switch (domain) {
2357 case LTTNG_DOMAIN_KERNEL:
2358 {
2359 struct ltt_kernel_session *ksess = session->kernel_session;
2360
2361 assert(ksess);
2362
2363 /* Can't register a consumer if there is already one */
2364 if (ksess->consumer_fds_sent != 0) {
2365 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2366 goto error;
2367 }
2368
2369 sock = lttcomm_connect_unix_sock(sock_path);
2370 if (sock < 0) {
2371 ret = LTTNG_ERR_CONNECT_FAIL;
2372 goto error;
2373 }
2374 cdata->cmd_sock = sock;
2375
2376 socket = consumer_allocate_socket(&cdata->cmd_sock);
2377 if (socket == NULL) {
2378 ret = close(sock);
2379 if (ret < 0) {
2380 PERROR("close register consumer");
2381 }
2382 cdata->cmd_sock = -1;
2383 ret = LTTNG_ERR_FATAL;
2384 goto error;
2385 }
2386
2387 socket->lock = zmalloc(sizeof(pthread_mutex_t));
2388 if (socket->lock == NULL) {
2389 PERROR("zmalloc pthread mutex");
2390 ret = LTTNG_ERR_FATAL;
2391 goto error;
2392 }
2393 pthread_mutex_init(socket->lock, NULL);
2394 socket->registered = 1;
2395
2396 rcu_read_lock();
2397 consumer_add_socket(socket, ksess->consumer);
2398 rcu_read_unlock();
2399
2400 pthread_mutex_lock(&cdata->pid_mutex);
2401 cdata->pid = -1;
2402 pthread_mutex_unlock(&cdata->pid_mutex);
2403
2404 break;
2405 }
2406 default:
2407 /* TODO: Userspace tracing */
2408 ret = LTTNG_ERR_UND;
2409 goto error;
2410 }
2411
2412 return LTTNG_OK;
2413
2414 error:
2415 if (socket) {
2416 consumer_destroy_socket(socket);
2417 }
2418 return ret;
2419 }
2420
2421 /*
2422 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2423 */
2424 ssize_t cmd_list_domains(struct ltt_session *session,
2425 struct lttng_domain **domains)
2426 {
2427 int ret, index = 0;
2428 ssize_t nb_dom = 0;
2429 struct agent *agt;
2430 struct lttng_ht_iter iter;
2431
2432 if (session->kernel_session != NULL) {
2433 DBG3("Listing domains found kernel domain");
2434 nb_dom++;
2435 }
2436
2437 if (session->ust_session != NULL) {
2438 DBG3("Listing domains found UST global domain");
2439 nb_dom++;
2440
2441 rcu_read_lock();
2442 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2443 agt, node.node) {
2444 if (agt->being_used) {
2445 nb_dom++;
2446 }
2447 }
2448 rcu_read_unlock();
2449 }
2450
2451 if (!nb_dom) {
2452 goto end;
2453 }
2454
2455 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2456 if (*domains == NULL) {
2457 ret = LTTNG_ERR_FATAL;
2458 goto error;
2459 }
2460
2461 if (session->kernel_session != NULL) {
2462 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2463
2464 /* Kernel session buffer type is always GLOBAL */
2465 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
2466
2467 index++;
2468 }
2469
2470 if (session->ust_session != NULL) {
2471 (*domains)[index].type = LTTNG_DOMAIN_UST;
2472 (*domains)[index].buf_type = session->ust_session->buffer_type;
2473 index++;
2474
2475 rcu_read_lock();
2476 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2477 agt, node.node) {
2478 if (agt->being_used) {
2479 (*domains)[index].type = agt->domain;
2480 (*domains)[index].buf_type = session->ust_session->buffer_type;
2481 index++;
2482 }
2483 }
2484 rcu_read_unlock();
2485 }
2486 end:
2487 return nb_dom;
2488
2489 error:
2490 /* Return negative value to differentiate return code */
2491 return -ret;
2492 }
2493
2494
2495 /*
2496 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2497 */
2498 ssize_t cmd_list_channels(int domain, struct ltt_session *session,
2499 struct lttng_channel **channels)
2500 {
2501 int ret;
2502 ssize_t nb_chan = 0;
2503
2504 switch (domain) {
2505 case LTTNG_DOMAIN_KERNEL:
2506 if (session->kernel_session != NULL) {
2507 nb_chan = session->kernel_session->channel_count;
2508 }
2509 DBG3("Number of kernel channels %zd", nb_chan);
2510 if (nb_chan <= 0) {
2511 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
2512 }
2513 break;
2514 case LTTNG_DOMAIN_UST:
2515 if (session->ust_session != NULL) {
2516 rcu_read_lock();
2517 nb_chan = lttng_ht_get_count(
2518 session->ust_session->domain_global.channels);
2519 rcu_read_unlock();
2520 }
2521 DBG3("Number of UST global channels %zd", nb_chan);
2522 if (nb_chan < 0) {
2523 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2524 goto error;
2525 }
2526 break;
2527 default:
2528 ret = LTTNG_ERR_UND;
2529 goto error;
2530 }
2531
2532 if (nb_chan > 0) {
2533 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
2534 if (*channels == NULL) {
2535 ret = LTTNG_ERR_FATAL;
2536 goto error;
2537 }
2538
2539 list_lttng_channels(domain, session, *channels);
2540 }
2541
2542 return nb_chan;
2543
2544 error:
2545 /* Return negative value to differentiate return code */
2546 return -ret;
2547 }
2548
2549 /*
2550 * Command LTTNG_LIST_EVENTS processed by the client thread.
2551 */
2552 ssize_t cmd_list_events(int domain, struct ltt_session *session,
2553 char *channel_name, struct lttng_event **events)
2554 {
2555 int ret = 0;
2556 ssize_t nb_event = 0;
2557
2558 switch (domain) {
2559 case LTTNG_DOMAIN_KERNEL:
2560 if (session->kernel_session != NULL) {
2561 nb_event = list_lttng_kernel_events(channel_name,
2562 session->kernel_session, events);
2563 }
2564 break;
2565 case LTTNG_DOMAIN_UST:
2566 {
2567 if (session->ust_session != NULL) {
2568 nb_event = list_lttng_ust_global_events(channel_name,
2569 &session->ust_session->domain_global, events);
2570 }
2571 break;
2572 }
2573 case LTTNG_DOMAIN_LOG4J:
2574 case LTTNG_DOMAIN_JUL:
2575 case LTTNG_DOMAIN_PYTHON:
2576 if (session->ust_session) {
2577 struct lttng_ht_iter iter;
2578 struct agent *agt;
2579
2580 rcu_read_lock();
2581 cds_lfht_for_each_entry(session->ust_session->agents->ht,
2582 &iter.iter, agt, node.node) {
2583 nb_event = list_lttng_agent_events(agt, events);
2584 }
2585 rcu_read_unlock();
2586 }
2587 break;
2588 default:
2589 ret = LTTNG_ERR_UND;
2590 goto error;
2591 }
2592
2593 return nb_event;
2594
2595 error:
2596 /* Return negative value to differentiate return code */
2597 return -ret;
2598 }
2599
2600 /*
2601 * Using the session list, filled a lttng_session array to send back to the
2602 * client for session listing.
2603 *
2604 * The session list lock MUST be acquired before calling this function. Use
2605 * session_lock_list() and session_unlock_list().
2606 */
2607 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2608 gid_t gid)
2609 {
2610 int ret;
2611 unsigned int i = 0;
2612 struct ltt_session *session;
2613 struct ltt_session_list *list = session_get_list();
2614
2615 DBG("Getting all available session for UID %d GID %d",
2616 uid, gid);
2617 /*
2618 * Iterate over session list and append data after the control struct in
2619 * the buffer.
2620 */
2621 cds_list_for_each_entry(session, &list->head, list) {
2622 /*
2623 * Only list the sessions the user can control.
2624 */
2625 if (!session_access_ok(session, uid, gid)) {
2626 continue;
2627 }
2628
2629 struct ltt_kernel_session *ksess = session->kernel_session;
2630 struct ltt_ust_session *usess = session->ust_session;
2631
2632 if (session->consumer->type == CONSUMER_DST_NET ||
2633 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2634 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2635 ret = build_network_session_path(sessions[i].path,
2636 sizeof(sessions[i].path), session);
2637 } else {
2638 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
2639 session->consumer->dst.trace_path);
2640 }
2641 if (ret < 0) {
2642 PERROR("snprintf session path");
2643 continue;
2644 }
2645
2646 strncpy(sessions[i].name, session->name, NAME_MAX);
2647 sessions[i].name[NAME_MAX - 1] = '\0';
2648 sessions[i].enabled = session->active;
2649 sessions[i].snapshot_mode = session->snapshot_mode;
2650 sessions[i].live_timer_interval = session->live_timer;
2651 i++;
2652 }
2653 }
2654
2655 /*
2656 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2657 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
2658 */
2659 int cmd_data_pending(struct ltt_session *session)
2660 {
2661 int ret;
2662 struct ltt_kernel_session *ksess = session->kernel_session;
2663 struct ltt_ust_session *usess = session->ust_session;
2664
2665 assert(session);
2666
2667 /* Session MUST be stopped to ask for data availability. */
2668 if (session->active) {
2669 ret = LTTNG_ERR_SESSION_STARTED;
2670 goto error;
2671 } else {
2672 /*
2673 * If stopped, just make sure we've started before else the above call
2674 * will always send that there is data pending.
2675 *
2676 * The consumer assumes that when the data pending command is received,
2677 * the trace has been started before or else no output data is written
2678 * by the streams which is a condition for data pending. So, this is
2679 * *VERY* important that we don't ask the consumer before a start
2680 * trace.
2681 */
2682 if (!session->has_been_started) {
2683 ret = 0;
2684 goto error;
2685 }
2686 }
2687
2688 if (ksess && ksess->consumer) {
2689 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2690 if (ret == 1) {
2691 /* Data is still being extracted for the kernel. */
2692 goto error;
2693 }
2694 }
2695
2696 if (usess && usess->consumer) {
2697 ret = consumer_is_data_pending(usess->id, usess->consumer);
2698 if (ret == 1) {
2699 /* Data is still being extracted for the kernel. */
2700 goto error;
2701 }
2702 }
2703
2704 /* Data is ready to be read by a viewer */
2705 ret = 0;
2706
2707 error:
2708 return ret;
2709 }
2710
2711 /*
2712 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
2713 *
2714 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2715 */
2716 int cmd_snapshot_add_output(struct ltt_session *session,
2717 struct lttng_snapshot_output *output, uint32_t *id)
2718 {
2719 int ret;
2720 struct snapshot_output *new_output;
2721
2722 assert(session);
2723 assert(output);
2724
2725 DBG("Cmd snapshot add output for session %s", session->name);
2726
2727 /*
2728 * Permission denied to create an output if the session is not
2729 * set in no output mode.
2730 */
2731 if (session->output_traces) {
2732 ret = LTTNG_ERR_EPERM;
2733 goto error;
2734 }
2735
2736 /* Only one output is allowed until we have the "tee" feature. */
2737 if (session->snapshot.nb_output == 1) {
2738 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
2739 goto error;
2740 }
2741
2742 new_output = snapshot_output_alloc();
2743 if (!new_output) {
2744 ret = LTTNG_ERR_NOMEM;
2745 goto error;
2746 }
2747
2748 ret = snapshot_output_init(output->max_size, output->name,
2749 output->ctrl_url, output->data_url, session->consumer, new_output,
2750 &session->snapshot);
2751 if (ret < 0) {
2752 if (ret == -ENOMEM) {
2753 ret = LTTNG_ERR_NOMEM;
2754 } else {
2755 ret = LTTNG_ERR_INVALID;
2756 }
2757 goto free_error;
2758 }
2759
2760 rcu_read_lock();
2761 snapshot_add_output(&session->snapshot, new_output);
2762 if (id) {
2763 *id = new_output->id;
2764 }
2765 rcu_read_unlock();
2766
2767 return LTTNG_OK;
2768
2769 free_error:
2770 snapshot_output_destroy(new_output);
2771 error:
2772 return ret;
2773 }
2774
2775 /*
2776 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
2777 *
2778 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2779 */
2780 int cmd_snapshot_del_output(struct ltt_session *session,
2781 struct lttng_snapshot_output *output)
2782 {
2783 int ret;
2784 struct snapshot_output *sout = NULL;
2785
2786 assert(session);
2787 assert(output);
2788
2789 rcu_read_lock();
2790
2791 /*
2792 * Permission denied to create an output if the session is not
2793 * set in no output mode.
2794 */
2795 if (session->output_traces) {
2796 ret = LTTNG_ERR_EPERM;
2797 goto error;
2798 }
2799
2800 if (output->id) {
2801 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
2802 session->name);
2803 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
2804 } else if (*output->name != '\0') {
2805 DBG("Cmd snapshot del output name %s for session %s", output->name,
2806 session->name);
2807 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
2808 }
2809 if (!sout) {
2810 ret = LTTNG_ERR_INVALID;
2811 goto error;
2812 }
2813
2814 snapshot_delete_output(&session->snapshot, sout);
2815 snapshot_output_destroy(sout);
2816 ret = LTTNG_OK;
2817
2818 error:
2819 rcu_read_unlock();
2820 return ret;
2821 }
2822
2823 /*
2824 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
2825 *
2826 * If no output is available, outputs is untouched and 0 is returned.
2827 *
2828 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
2829 */
2830 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
2831 struct lttng_snapshot_output **outputs)
2832 {
2833 int ret, idx = 0;
2834 struct lttng_snapshot_output *list = NULL;
2835 struct lttng_ht_iter iter;
2836 struct snapshot_output *output;
2837
2838 assert(session);
2839 assert(outputs);
2840
2841 DBG("Cmd snapshot list outputs 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 if (session->snapshot.nb_output == 0) {
2853 ret = 0;
2854 goto error;
2855 }
2856
2857 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
2858 if (!list) {
2859 ret = -LTTNG_ERR_NOMEM;
2860 goto error;
2861 }
2862
2863 /* Copy list from session to the new list object. */
2864 rcu_read_lock();
2865 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
2866 output, node.node) {
2867 assert(output->consumer);
2868 list[idx].id = output->id;
2869 list[idx].max_size = output->max_size;
2870 strncpy(list[idx].name, output->name, sizeof(list[idx].name));
2871 if (output->consumer->type == CONSUMER_DST_LOCAL) {
2872 strncpy(list[idx].ctrl_url, output->consumer->dst.trace_path,
2873 sizeof(list[idx].ctrl_url));
2874 } else {
2875 /* Control URI. */
2876 ret = uri_to_str_url(&output->consumer->dst.net.control,
2877 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
2878 if (ret < 0) {
2879 ret = -LTTNG_ERR_NOMEM;
2880 goto error;
2881 }
2882
2883 /* Data URI. */
2884 ret = uri_to_str_url(&output->consumer->dst.net.data,
2885 list[idx].data_url, sizeof(list[idx].data_url));
2886 if (ret < 0) {
2887 ret = -LTTNG_ERR_NOMEM;
2888 goto error;
2889 }
2890 }
2891 idx++;
2892 }
2893
2894 *outputs = list;
2895 list = NULL;
2896 ret = session->snapshot.nb_output;
2897 error:
2898 free(list);
2899 rcu_read_unlock();
2900 return ret;
2901 }
2902
2903 /*
2904 * Send relayd sockets from snapshot output to consumer. Ignore request if the
2905 * snapshot output is *not* set with a remote destination.
2906 *
2907 * Return 0 on success or a LTTNG_ERR code.
2908 */
2909 static int set_relayd_for_snapshot(struct consumer_output *consumer,
2910 struct snapshot_output *snap_output, struct ltt_session *session)
2911 {
2912 int ret = LTTNG_OK;
2913 struct lttng_ht_iter iter;
2914 struct consumer_socket *socket;
2915
2916 assert(consumer);
2917 assert(snap_output);
2918 assert(session);
2919
2920 DBG2("Set relayd object from snapshot output");
2921
2922 /* Ignore if snapshot consumer output is not network. */
2923 if (snap_output->consumer->type != CONSUMER_DST_NET) {
2924 goto error;
2925 }
2926
2927 /*
2928 * For each consumer socket, create and send the relayd object of the
2929 * snapshot output.
2930 */
2931 rcu_read_lock();
2932 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
2933 socket, node.node) {
2934 ret = send_consumer_relayd_sockets(0, session->id,
2935 snap_output->consumer, socket,
2936 session->name, session->hostname,
2937 session->live_timer);
2938 if (ret != LTTNG_OK) {
2939 rcu_read_unlock();
2940 goto error;
2941 }
2942 }
2943 rcu_read_unlock();
2944
2945 error:
2946 return ret;
2947 }
2948
2949 /*
2950 * Record a kernel snapshot.
2951 *
2952 * Return LTTNG_OK on success or a LTTNG_ERR code.
2953 */
2954 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
2955 struct snapshot_output *output, struct ltt_session *session,
2956 int wait, uint64_t nb_packets_per_stream)
2957 {
2958 int ret;
2959
2960 assert(ksess);
2961 assert(output);
2962 assert(session);
2963
2964 /* Get the datetime for the snapshot output directory. */
2965 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
2966 sizeof(output->datetime));
2967 if (!ret) {
2968 ret = LTTNG_ERR_INVALID;
2969 goto error;
2970 }
2971
2972 /*
2973 * Copy kernel session sockets so we can communicate with the right
2974 * consumer for the snapshot record command.
2975 */
2976 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
2977 if (ret < 0) {
2978 ret = LTTNG_ERR_NOMEM;
2979 goto error;
2980 }
2981
2982 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
2983 if (ret != LTTNG_OK) {
2984 goto error_snapshot;
2985 }
2986
2987 ret = kernel_snapshot_record(ksess, output, wait, nb_packets_per_stream);
2988 if (ret != LTTNG_OK) {
2989 goto error_snapshot;
2990 }
2991
2992 ret = LTTNG_OK;
2993 goto end;
2994
2995 error_snapshot:
2996 /* Clean up copied sockets so this output can use some other later on. */
2997 consumer_destroy_output_sockets(output->consumer);
2998 error:
2999 end:
3000 return ret;
3001 }
3002
3003 /*
3004 * Record a UST snapshot.
3005 *
3006 * Return 0 on success or a LTTNG_ERR error code.
3007 */
3008 static int record_ust_snapshot(struct ltt_ust_session *usess,
3009 struct snapshot_output *output, struct ltt_session *session,
3010 int wait, uint64_t nb_packets_per_stream)
3011 {
3012 int ret;
3013
3014 assert(usess);
3015 assert(output);
3016 assert(session);
3017
3018 /* Get the datetime for the snapshot output directory. */
3019 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
3020 sizeof(output->datetime));
3021 if (!ret) {
3022 ret = LTTNG_ERR_INVALID;
3023 goto error;
3024 }
3025
3026 /*
3027 * Copy UST session sockets so we can communicate with the right
3028 * consumer for the snapshot record command.
3029 */
3030 ret = consumer_copy_sockets(output->consumer, usess->consumer);
3031 if (ret < 0) {
3032 ret = LTTNG_ERR_NOMEM;
3033 goto error;
3034 }
3035
3036 ret = set_relayd_for_snapshot(usess->consumer, output, session);
3037 if (ret != LTTNG_OK) {
3038 goto error_snapshot;
3039 }
3040
3041 ret = ust_app_snapshot_record(usess, output, wait, nb_packets_per_stream);
3042 if (ret < 0) {
3043 switch (-ret) {
3044 case EINVAL:
3045 ret = LTTNG_ERR_INVALID;
3046 break;
3047 case ENODATA:
3048 ret = LTTNG_ERR_SNAPSHOT_NODATA;
3049 break;
3050 default:
3051 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3052 break;
3053 }
3054 goto error_snapshot;
3055 }
3056
3057 ret = LTTNG_OK;
3058
3059 error_snapshot:
3060 /* Clean up copied sockets so this output can use some other later on. */
3061 consumer_destroy_output_sockets(output->consumer);
3062 error:
3063 return ret;
3064 }
3065
3066 static
3067 uint64_t get_session_size_one_more_packet_per_stream(struct ltt_session *session,
3068 uint64_t cur_nr_packets)
3069 {
3070 uint64_t tot_size = 0;
3071
3072 if (session->kernel_session) {
3073 struct ltt_kernel_channel *chan;
3074 struct ltt_kernel_session *ksess = session->kernel_session;
3075
3076 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
3077 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
3078 /*
3079 * Don't take channel into account if we
3080 * already grab all its packets.
3081 */
3082 continue;
3083 }
3084 tot_size += chan->channel->attr.subbuf_size
3085 * chan->stream_count;
3086 }
3087 }
3088
3089 if (session->ust_session) {
3090 struct ltt_ust_session *usess = session->ust_session;
3091
3092 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
3093 cur_nr_packets);
3094 }
3095
3096 return tot_size;
3097 }
3098
3099 /*
3100 * Calculate the number of packets we can grab from each stream that
3101 * fits within the overall snapshot max size.
3102 *
3103 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
3104 * the number of packets per stream.
3105 *
3106 * TODO: this approach is not perfect: we consider the worse case
3107 * (packet filling the sub-buffers) as an upper bound, but we could do
3108 * better if we do this calculation while we actually grab the packet
3109 * content: we would know how much padding we don't actually store into
3110 * the file.
3111 *
3112 * This algorithm is currently bounded by the number of packets per
3113 * stream.
3114 *
3115 * Since we call this algorithm before actually grabbing the data, it's
3116 * an approximation: for instance, applications could appear/disappear
3117 * in between this call and actually grabbing data.
3118 */
3119 static
3120 int64_t get_session_nb_packets_per_stream(struct ltt_session *session, uint64_t max_size)
3121 {
3122 int64_t size_left;
3123 uint64_t cur_nb_packets = 0;
3124
3125 if (!max_size) {
3126 return 0; /* Infinite */
3127 }
3128
3129 size_left = max_size;
3130 for (;;) {
3131 uint64_t one_more_packet_tot_size;
3132
3133 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(session,
3134 cur_nb_packets);
3135 if (!one_more_packet_tot_size) {
3136 /* We are already grabbing all packets. */
3137 break;
3138 }
3139 size_left -= one_more_packet_tot_size;
3140 if (size_left < 0) {
3141 break;
3142 }
3143 cur_nb_packets++;
3144 }
3145 if (!cur_nb_packets) {
3146 /* Not enough room to grab one packet of each stream, error. */
3147 return -1;
3148 }
3149 return cur_nb_packets;
3150 }
3151
3152 /*
3153 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
3154 *
3155 * The wait parameter is ignored so this call always wait for the snapshot to
3156 * complete before returning.
3157 *
3158 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3159 */
3160 int cmd_snapshot_record(struct ltt_session *session,
3161 struct lttng_snapshot_output *output, int wait)
3162 {
3163 int ret = LTTNG_OK;
3164 unsigned int use_tmp_output = 0;
3165 struct snapshot_output tmp_output;
3166 unsigned int snapshot_success = 0;
3167
3168 assert(session);
3169 assert(output);
3170
3171 DBG("Cmd snapshot record for session %s", session->name);
3172
3173 /*
3174 * Permission denied to create an output if the session is not
3175 * set in no output mode.
3176 */
3177 if (session->output_traces) {
3178 ret = LTTNG_ERR_EPERM;
3179 goto error;
3180 }
3181
3182 /* The session needs to be started at least once. */
3183 if (!session->has_been_started) {
3184 ret = LTTNG_ERR_START_SESSION_ONCE;
3185 goto error;
3186 }
3187
3188 /* Use temporary output for the session. */
3189 if (*output->ctrl_url != '\0') {
3190 ret = snapshot_output_init(output->max_size, output->name,
3191 output->ctrl_url, output->data_url, session->consumer,
3192 &tmp_output, NULL);
3193 if (ret < 0) {
3194 if (ret == -ENOMEM) {
3195 ret = LTTNG_ERR_NOMEM;
3196 } else {
3197 ret = LTTNG_ERR_INVALID;
3198 }
3199 goto error;
3200 }
3201 /* Use the global session count for the temporary snapshot. */
3202 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3203 use_tmp_output = 1;
3204 }
3205
3206 if (session->kernel_session) {
3207 struct ltt_kernel_session *ksess = session->kernel_session;
3208
3209 if (use_tmp_output) {
3210 int64_t nb_packets_per_stream;
3211
3212 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3213 tmp_output.max_size);
3214 if (nb_packets_per_stream < 0) {
3215 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3216 goto error;
3217 }
3218 ret = record_kernel_snapshot(ksess, &tmp_output, session,
3219 wait, nb_packets_per_stream);
3220 if (ret != LTTNG_OK) {
3221 goto error;
3222 }
3223 snapshot_success = 1;
3224 } else {
3225 struct snapshot_output *sout;
3226 struct lttng_ht_iter iter;
3227
3228 rcu_read_lock();
3229 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3230 &iter.iter, sout, node.node) {
3231 int64_t nb_packets_per_stream;
3232
3233 /*
3234 * Make a local copy of the output and assign the possible
3235 * temporary value given by the caller.
3236 */
3237 memset(&tmp_output, 0, sizeof(tmp_output));
3238 memcpy(&tmp_output, sout, sizeof(tmp_output));
3239
3240 if (output->max_size != (uint64_t) -1ULL) {
3241 tmp_output.max_size = output->max_size;
3242 }
3243
3244 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3245 tmp_output.max_size);
3246 if (nb_packets_per_stream < 0) {
3247 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3248 goto error;
3249 }
3250
3251 /* Use temporary name. */
3252 if (*output->name != '\0') {
3253 strncpy(tmp_output.name, output->name,
3254 sizeof(tmp_output.name));
3255 }
3256
3257 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3258
3259 ret = record_kernel_snapshot(ksess, &tmp_output,
3260 session, wait, nb_packets_per_stream);
3261 if (ret != LTTNG_OK) {
3262 rcu_read_unlock();
3263 goto error;
3264 }
3265 snapshot_success = 1;
3266 }
3267 rcu_read_unlock();
3268 }
3269 }
3270
3271 if (session->ust_session) {
3272 struct ltt_ust_session *usess = session->ust_session;
3273
3274 if (use_tmp_output) {
3275 int64_t nb_packets_per_stream;
3276
3277 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3278 tmp_output.max_size);
3279 if (nb_packets_per_stream < 0) {
3280 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3281 goto error;
3282 }
3283 ret = record_ust_snapshot(usess, &tmp_output, session,
3284 wait, nb_packets_per_stream);
3285 if (ret != LTTNG_OK) {
3286 goto error;
3287 }
3288 snapshot_success = 1;
3289 } else {
3290 struct snapshot_output *sout;
3291 struct lttng_ht_iter iter;
3292
3293 rcu_read_lock();
3294 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3295 &iter.iter, sout, node.node) {
3296 int64_t nb_packets_per_stream;
3297
3298 /*
3299 * Make a local copy of the output and assign the possible
3300 * temporary value given by the caller.
3301 */
3302 memset(&tmp_output, 0, sizeof(tmp_output));
3303 memcpy(&tmp_output, sout, sizeof(tmp_output));
3304
3305 if (output->max_size != (uint64_t) -1ULL) {
3306 tmp_output.max_size = output->max_size;
3307 }
3308
3309 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3310 tmp_output.max_size);
3311 if (nb_packets_per_stream < 0) {
3312 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3313 rcu_read_unlock();
3314 goto error;
3315 }
3316
3317 /* Use temporary name. */
3318 if (*output->name != '\0') {
3319 strncpy(tmp_output.name, output->name,
3320 sizeof(tmp_output.name));
3321 }
3322
3323 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3324
3325 ret = record_ust_snapshot(usess, &tmp_output, session,
3326 wait, nb_packets_per_stream);
3327 if (ret != LTTNG_OK) {
3328 rcu_read_unlock();
3329 goto error;
3330 }
3331 snapshot_success = 1;
3332 }
3333 rcu_read_unlock();
3334 }
3335 }
3336
3337 if (snapshot_success) {
3338 session->snapshot.nb_snapshot++;
3339 } else {
3340 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3341 }
3342
3343 error:
3344 return ret;
3345 }
3346
3347 /*
3348 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
3349 */
3350 int cmd_set_session_shm_path(struct ltt_session *session,
3351 const char *shm_path)
3352 {
3353 /* Safety net */
3354 assert(session);
3355
3356 /*
3357 * Can only set shm path before session is started.
3358 */
3359 if (session->has_been_started) {
3360 return LTTNG_ERR_SESSION_STARTED;
3361 }
3362
3363 strncpy(session->shm_path, shm_path,
3364 sizeof(session->shm_path));
3365 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
3366
3367 return 0;
3368 }
3369
3370 /*
3371 * Init command subsystem.
3372 */
3373 void cmd_init(void)
3374 {
3375 /*
3376 * Set network sequence index to 1 for streams to match a relayd
3377 * socket on the consumer side.
3378 */
3379 pthread_mutex_lock(&relayd_net_seq_idx_lock);
3380 relayd_net_seq_idx = 1;
3381 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
3382
3383 DBG("Command subsystem initialized");
3384 }
LTTng 2.0 tools and control repository
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