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Fix: double free on enable-event
[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c
1 /*
2 * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License, version 2 only, as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
11 * more details.
12 *
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 51
15 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
16 */
17
18 #define _GNU_SOURCE
19 #define _LGPL_SOURCE
20 #include <assert.h>
21 #include <string.h>
22 #include <inttypes.h>
23 #include <urcu/list.h>
24 #include <urcu/uatomic.h>
25
26 #include <common/defaults.h>
27 #include <common/common.h>
28 #include <common/sessiond-comm/sessiond-comm.h>
29 #include <common/relayd/relayd.h>
30 #include <common/utils.h>
31
32 #include "channel.h"
33 #include "consumer.h"
34 #include "event.h"
35 #include "health-sessiond.h"
36 #include "kernel.h"
37 #include "kernel-consumer.h"
38 #include "lttng-sessiond.h"
39 #include "utils.h"
40 #include "syscall.h"
41
42 #include "cmd.h"
43
44 /*
45 * Used to keep a unique index for each relayd socket created where this value
46 * is associated with streams on the consumer so it can match the right relayd
47 * to send to. It must be accessed with the relayd_net_seq_idx_lock
48 * held.
49 */
50 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
51 static uint64_t relayd_net_seq_idx;
52
53 static int validate_event_name(const char *);
54 static int validate_ust_event_name(const char *);
55 static int cmd_enable_event_internal(struct ltt_session *session,
56 struct lttng_domain *domain,
57 char *channel_name, struct lttng_event *event,
58 char *filter_expression,
59 struct lttng_filter_bytecode *filter,
60 struct lttng_event_exclusion *exclusion,
61 int wpipe);
62
63 /*
64 * Create a session path used by list_lttng_sessions for the case that the
65 * session consumer is on the network.
66 */
67 static int build_network_session_path(char *dst, size_t size,
68 struct ltt_session *session)
69 {
70 int ret, kdata_port, udata_port;
71 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
72 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
73
74 assert(session);
75 assert(dst);
76
77 memset(tmp_urls, 0, sizeof(tmp_urls));
78 memset(tmp_uurl, 0, sizeof(tmp_uurl));
79
80 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
81
82 if (session->kernel_session && session->kernel_session->consumer) {
83 kuri = &session->kernel_session->consumer->dst.net.control;
84 kdata_port = session->kernel_session->consumer->dst.net.data.port;
85 }
86
87 if (session->ust_session && session->ust_session->consumer) {
88 uuri = &session->ust_session->consumer->dst.net.control;
89 udata_port = session->ust_session->consumer->dst.net.data.port;
90 }
91
92 if (uuri == NULL && kuri == NULL) {
93 uri = &session->consumer->dst.net.control;
94 kdata_port = session->consumer->dst.net.data.port;
95 } else if (kuri && uuri) {
96 ret = uri_compare(kuri, uuri);
97 if (ret) {
98 /* Not Equal */
99 uri = kuri;
100 /* Build uuri URL string */
101 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
102 if (ret < 0) {
103 goto error;
104 }
105 } else {
106 uri = kuri;
107 }
108 } else if (kuri && uuri == NULL) {
109 uri = kuri;
110 } else if (uuri && kuri == NULL) {
111 uri = uuri;
112 }
113
114 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
115 if (ret < 0) {
116 goto error;
117 }
118
119 /*
120 * Do we have a UST url set. If yes, this means we have both kernel and UST
121 * to print.
122 */
123 if (*tmp_uurl != '\0') {
124 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
125 tmp_urls, kdata_port, tmp_uurl, udata_port);
126 } else {
127 int dport;
128 if (kuri || (!kuri && !uuri)) {
129 dport = kdata_port;
130 } else {
131 /* No kernel URI, use the UST port. */
132 dport = udata_port;
133 }
134 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
135 }
136
137 error:
138 return ret;
139 }
140
141 /*
142 * Fill lttng_channel array of all channels.
143 */
144 static void list_lttng_channels(int domain, struct ltt_session *session,
145 struct lttng_channel *channels)
146 {
147 int i = 0;
148 struct ltt_kernel_channel *kchan;
149
150 DBG("Listing channels for session %s", session->name);
151
152 switch (domain) {
153 case LTTNG_DOMAIN_KERNEL:
154 /* Kernel channels */
155 if (session->kernel_session != NULL) {
156 cds_list_for_each_entry(kchan,
157 &session->kernel_session->channel_list.head, list) {
158 /* Copy lttng_channel struct to array */
159 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
160 channels[i].enabled = kchan->enabled;
161 i++;
162 }
163 }
164 break;
165 case LTTNG_DOMAIN_UST:
166 {
167 struct lttng_ht_iter iter;
168 struct ltt_ust_channel *uchan;
169
170 rcu_read_lock();
171 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
172 &iter.iter, uchan, node.node) {
173 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
174 channels[i].attr.overwrite = uchan->attr.overwrite;
175 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
176 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
177 channels[i].attr.switch_timer_interval =
178 uchan->attr.switch_timer_interval;
179 channels[i].attr.read_timer_interval =
180 uchan->attr.read_timer_interval;
181 channels[i].enabled = uchan->enabled;
182 channels[i].attr.tracefile_size = uchan->tracefile_size;
183 channels[i].attr.tracefile_count = uchan->tracefile_count;
184 switch (uchan->attr.output) {
185 case LTTNG_UST_MMAP:
186 default:
187 channels[i].attr.output = LTTNG_EVENT_MMAP;
188 break;
189 }
190 i++;
191 }
192 rcu_read_unlock();
193 break;
194 }
195 default:
196 break;
197 }
198 }
199
200 /*
201 * Create a list of agent domain events.
202 *
203 * Return number of events in list on success or else a negative value.
204 */
205 static int list_lttng_agent_events(struct agent *agt,
206 struct lttng_event **events)
207 {
208 int i = 0, ret = 0;
209 unsigned int nb_event = 0;
210 struct agent_event *event;
211 struct lttng_event *tmp_events;
212 struct lttng_ht_iter iter;
213
214 assert(agt);
215 assert(events);
216
217 DBG3("Listing agent events");
218
219 rcu_read_lock();
220 nb_event = lttng_ht_get_count(agt->events);
221 rcu_read_unlock();
222 if (nb_event == 0) {
223 ret = nb_event;
224 goto error;
225 }
226
227 tmp_events = zmalloc(nb_event * sizeof(*tmp_events));
228 if (!tmp_events) {
229 PERROR("zmalloc agent events session");
230 ret = -LTTNG_ERR_FATAL;
231 goto error;
232 }
233
234 rcu_read_lock();
235 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
236 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
237 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
238 tmp_events[i].enabled = event->enabled;
239 tmp_events[i].loglevel = event->loglevel_value;
240 tmp_events[i].loglevel_type = event->loglevel_type;
241 i++;
242 }
243 rcu_read_unlock();
244
245 *events = tmp_events;
246 ret = nb_event;
247
248 error:
249 assert(nb_event == i);
250 return ret;
251 }
252
253 /*
254 * Create a list of ust global domain events.
255 */
256 static int list_lttng_ust_global_events(char *channel_name,
257 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
258 {
259 int i = 0, ret = 0;
260 unsigned int nb_event = 0;
261 struct lttng_ht_iter iter;
262 struct lttng_ht_node_str *node;
263 struct ltt_ust_channel *uchan;
264 struct ltt_ust_event *uevent;
265 struct lttng_event *tmp;
266
267 DBG("Listing UST global events for channel %s", channel_name);
268
269 rcu_read_lock();
270
271 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
272 node = lttng_ht_iter_get_node_str(&iter);
273 if (node == NULL) {
274 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
275 goto error;
276 }
277
278 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
279
280 nb_event = lttng_ht_get_count(uchan->events);
281 if (nb_event == 0) {
282 ret = nb_event;
283 goto error;
284 }
285
286 DBG3("Listing UST global %d events", nb_event);
287
288 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
289 if (tmp == NULL) {
290 ret = LTTNG_ERR_FATAL;
291 goto error;
292 }
293
294 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
295 if (uevent->internal) {
296 /* This event should remain hidden from clients */
297 nb_event--;
298 continue;
299 }
300 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
301 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
302 tmp[i].enabled = uevent->enabled;
303
304 switch (uevent->attr.instrumentation) {
305 case LTTNG_UST_TRACEPOINT:
306 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
307 break;
308 case LTTNG_UST_PROBE:
309 tmp[i].type = LTTNG_EVENT_PROBE;
310 break;
311 case LTTNG_UST_FUNCTION:
312 tmp[i].type = LTTNG_EVENT_FUNCTION;
313 break;
314 }
315
316 tmp[i].loglevel = uevent->attr.loglevel;
317 switch (uevent->attr.loglevel_type) {
318 case LTTNG_UST_LOGLEVEL_ALL:
319 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
320 break;
321 case LTTNG_UST_LOGLEVEL_RANGE:
322 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
323 break;
324 case LTTNG_UST_LOGLEVEL_SINGLE:
325 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
326 break;
327 }
328 if (uevent->filter) {
329 tmp[i].filter = 1;
330 }
331 if (uevent->exclusion) {
332 tmp[i].exclusion = 1;
333 }
334 i++;
335 }
336
337 ret = nb_event;
338 *events = tmp;
339
340 error:
341 rcu_read_unlock();
342 return ret;
343 }
344
345 /*
346 * Fill lttng_event array of all kernel events in the channel.
347 */
348 static int list_lttng_kernel_events(char *channel_name,
349 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
350 {
351 int i = 0, ret;
352 unsigned int nb_event;
353 struct ltt_kernel_event *event;
354 struct ltt_kernel_channel *kchan;
355
356 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
357 if (kchan == NULL) {
358 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
359 goto error;
360 }
361
362 nb_event = kchan->event_count;
363
364 DBG("Listing events for channel %s", kchan->channel->name);
365
366 if (nb_event == 0) {
367 *events = NULL;
368 goto syscall;
369 }
370
371 *events = zmalloc(nb_event * sizeof(struct lttng_event));
372 if (*events == NULL) {
373 ret = LTTNG_ERR_FATAL;
374 goto error;
375 }
376
377 /* Kernel channels */
378 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
379 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
380 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
381 (*events)[i].enabled = event->enabled;
382 (*events)[i].filter =
383 (unsigned char) !!event->filter_expression;
384
385 switch (event->event->instrumentation) {
386 case LTTNG_KERNEL_TRACEPOINT:
387 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
388 break;
389 case LTTNG_KERNEL_KRETPROBE:
390 (*events)[i].type = LTTNG_EVENT_FUNCTION;
391 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
392 sizeof(struct lttng_kernel_kprobe));
393 break;
394 case LTTNG_KERNEL_KPROBE:
395 (*events)[i].type = LTTNG_EVENT_PROBE;
396 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
397 sizeof(struct lttng_kernel_kprobe));
398 break;
399 case LTTNG_KERNEL_FUNCTION:
400 (*events)[i].type = LTTNG_EVENT_FUNCTION;
401 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
402 sizeof(struct lttng_kernel_function));
403 break;
404 case LTTNG_KERNEL_NOOP:
405 (*events)[i].type = LTTNG_EVENT_NOOP;
406 break;
407 case LTTNG_KERNEL_SYSCALL:
408 (*events)[i].type = LTTNG_EVENT_SYSCALL;
409 break;
410 case LTTNG_KERNEL_ALL:
411 assert(0);
412 break;
413 }
414 i++;
415 }
416
417 syscall:
418 if (syscall_table) {
419 ssize_t new_size;
420
421 new_size = syscall_list_channel(kchan, events, nb_event);
422 if (new_size < 0) {
423 free(events);
424 ret = -new_size;
425 goto error;
426 }
427 nb_event = new_size;
428 }
429
430 return nb_event;
431
432 error:
433 /* Negate the error code to differentiate the size from an error */
434 return -ret;
435 }
436
437 /*
438 * Add URI so the consumer output object. Set the correct path depending on the
439 * domain adding the default trace directory.
440 */
441 static int add_uri_to_consumer(struct consumer_output *consumer,
442 struct lttng_uri *uri, int domain, const char *session_name)
443 {
444 int ret = LTTNG_OK;
445 const char *default_trace_dir;
446
447 assert(uri);
448
449 if (consumer == NULL) {
450 DBG("No consumer detected. Don't add URI. Stopping.");
451 ret = LTTNG_ERR_NO_CONSUMER;
452 goto error;
453 }
454
455 switch (domain) {
456 case LTTNG_DOMAIN_KERNEL:
457 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
458 break;
459 case LTTNG_DOMAIN_UST:
460 default_trace_dir = DEFAULT_UST_TRACE_DIR;
461 break;
462 default:
463 /*
464 * This case is possible is we try to add the URI to the global tracing
465 * session consumer object which in this case there is no subdir.
466 */
467 default_trace_dir = "";
468 }
469
470 switch (uri->dtype) {
471 case LTTNG_DST_IPV4:
472 case LTTNG_DST_IPV6:
473 DBG2("Setting network URI to consumer");
474
475 if (consumer->type == CONSUMER_DST_NET) {
476 if ((uri->stype == LTTNG_STREAM_CONTROL &&
477 consumer->dst.net.control_isset) ||
478 (uri->stype == LTTNG_STREAM_DATA &&
479 consumer->dst.net.data_isset)) {
480 ret = LTTNG_ERR_URL_EXIST;
481 goto error;
482 }
483 } else {
484 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
485 }
486
487 consumer->type = CONSUMER_DST_NET;
488
489 /* Set URI into consumer output object */
490 ret = consumer_set_network_uri(consumer, uri);
491 if (ret < 0) {
492 ret = -ret;
493 goto error;
494 } else if (ret == 1) {
495 /*
496 * URI was the same in the consumer so we do not append the subdir
497 * again so to not duplicate output dir.
498 */
499 ret = LTTNG_OK;
500 goto error;
501 }
502
503 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
504 ret = consumer_set_subdir(consumer, session_name);
505 if (ret < 0) {
506 ret = LTTNG_ERR_FATAL;
507 goto error;
508 }
509 }
510
511 if (uri->stype == LTTNG_STREAM_CONTROL) {
512 /* On a new subdir, reappend the default trace dir. */
513 strncat(consumer->subdir, default_trace_dir,
514 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
515 DBG3("Append domain trace name to subdir %s", consumer->subdir);
516 }
517
518 break;
519 case LTTNG_DST_PATH:
520 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
521 memset(consumer->dst.trace_path, 0,
522 sizeof(consumer->dst.trace_path));
523 strncpy(consumer->dst.trace_path, uri->dst.path,
524 sizeof(consumer->dst.trace_path));
525 /* Append default trace dir */
526 strncat(consumer->dst.trace_path, default_trace_dir,
527 sizeof(consumer->dst.trace_path) -
528 strlen(consumer->dst.trace_path) - 1);
529 /* Flag consumer as local. */
530 consumer->type = CONSUMER_DST_LOCAL;
531 break;
532 }
533
534 ret = LTTNG_OK;
535
536 error:
537 return ret;
538 }
539
540 /*
541 * Init tracing by creating trace directory and sending fds kernel consumer.
542 */
543 static int init_kernel_tracing(struct ltt_kernel_session *session)
544 {
545 int ret = 0;
546 struct lttng_ht_iter iter;
547 struct consumer_socket *socket;
548
549 assert(session);
550
551 rcu_read_lock();
552
553 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
554 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
555 socket, node.node) {
556 pthread_mutex_lock(socket->lock);
557 ret = kernel_consumer_send_session(socket, session);
558 pthread_mutex_unlock(socket->lock);
559 if (ret < 0) {
560 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
561 goto error;
562 }
563 }
564 }
565
566 error:
567 rcu_read_unlock();
568 return ret;
569 }
570
571 /*
572 * Create a socket to the relayd using the URI.
573 *
574 * On success, the relayd_sock pointer is set to the created socket.
575 * Else, it's stays untouched and a lttcomm error code is returned.
576 */
577 static int create_connect_relayd(struct lttng_uri *uri,
578 struct lttcomm_relayd_sock **relayd_sock)
579 {
580 int ret;
581 struct lttcomm_relayd_sock *rsock;
582
583 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
584 RELAYD_VERSION_COMM_MINOR);
585 if (!rsock) {
586 ret = LTTNG_ERR_FATAL;
587 goto error;
588 }
589
590 /*
591 * Connect to relayd so we can proceed with a session creation. This call
592 * can possibly block for an arbitrary amount of time to set the health
593 * state to be in poll execution.
594 */
595 health_poll_entry();
596 ret = relayd_connect(rsock);
597 health_poll_exit();
598 if (ret < 0) {
599 ERR("Unable to reach lttng-relayd");
600 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
601 goto free_sock;
602 }
603
604 /* Create socket for control stream. */
605 if (uri->stype == LTTNG_STREAM_CONTROL) {
606 DBG3("Creating relayd stream socket from URI");
607
608 /* Check relayd version */
609 ret = relayd_version_check(rsock);
610 if (ret < 0) {
611 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
612 goto close_sock;
613 }
614 } else if (uri->stype == LTTNG_STREAM_DATA) {
615 DBG3("Creating relayd data socket from URI");
616 } else {
617 /* Command is not valid */
618 ERR("Relayd invalid stream type: %d", uri->stype);
619 ret = LTTNG_ERR_INVALID;
620 goto close_sock;
621 }
622
623 *relayd_sock = rsock;
624
625 return LTTNG_OK;
626
627 close_sock:
628 /* The returned value is not useful since we are on an error path. */
629 (void) relayd_close(rsock);
630 free_sock:
631 free(rsock);
632 error:
633 return ret;
634 }
635
636 /*
637 * Connect to the relayd using URI and send the socket to the right consumer.
638 */
639 static int send_consumer_relayd_socket(int domain, unsigned int session_id,
640 struct lttng_uri *relayd_uri, struct consumer_output *consumer,
641 struct consumer_socket *consumer_sock,
642 char *session_name, char *hostname, int session_live_timer)
643 {
644 int ret;
645 struct lttcomm_relayd_sock *rsock = NULL;
646
647 /* Connect to relayd and make version check if uri is the control. */
648 ret = create_connect_relayd(relayd_uri, &rsock);
649 if (ret != LTTNG_OK) {
650 goto error;
651 }
652 assert(rsock);
653
654 /* Set the network sequence index if not set. */
655 if (consumer->net_seq_index == (uint64_t) -1ULL) {
656 pthread_mutex_lock(&relayd_net_seq_idx_lock);
657 /*
658 * Increment net_seq_idx because we are about to transfer the
659 * new relayd socket to the consumer.
660 * Assign unique key so the consumer can match streams.
661 */
662 consumer->net_seq_index = ++relayd_net_seq_idx;
663 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
664 }
665
666 /* Send relayd socket to consumer. */
667 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
668 relayd_uri->stype, session_id,
669 session_name, hostname, session_live_timer);
670 if (ret < 0) {
671 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
672 goto close_sock;
673 }
674
675 /* Flag that the corresponding socket was sent. */
676 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
677 consumer_sock->control_sock_sent = 1;
678 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
679 consumer_sock->data_sock_sent = 1;
680 }
681
682 ret = LTTNG_OK;
683
684 /*
685 * Close socket which was dup on the consumer side. The session daemon does
686 * NOT keep track of the relayd socket(s) once transfer to the consumer.
687 */
688
689 close_sock:
690 (void) relayd_close(rsock);
691 free(rsock);
692
693 error:
694 if (ret != LTTNG_OK) {
695 /*
696 * The consumer output for this session should not be used anymore
697 * since the relayd connection failed thus making any tracing or/and
698 * streaming not usable.
699 */
700 consumer->enabled = 0;
701 }
702 return ret;
703 }
704
705 /*
706 * Send both relayd sockets to a specific consumer and domain. This is a
707 * helper function to facilitate sending the information to the consumer for a
708 * session.
709 */
710 static int send_consumer_relayd_sockets(int domain, unsigned int session_id,
711 struct consumer_output *consumer, struct consumer_socket *sock,
712 char *session_name, char *hostname, int session_live_timer)
713 {
714 int ret = LTTNG_OK;
715
716 assert(consumer);
717 assert(sock);
718
719 /* Sending control relayd socket. */
720 if (!sock->control_sock_sent) {
721 ret = send_consumer_relayd_socket(domain, session_id,
722 &consumer->dst.net.control, consumer, sock,
723 session_name, hostname, session_live_timer);
724 if (ret != LTTNG_OK) {
725 goto error;
726 }
727 }
728
729 /* Sending data relayd socket. */
730 if (!sock->data_sock_sent) {
731 ret = send_consumer_relayd_socket(domain, session_id,
732 &consumer->dst.net.data, consumer, sock,
733 session_name, hostname, session_live_timer);
734 if (ret != LTTNG_OK) {
735 goto error;
736 }
737 }
738
739 error:
740 return ret;
741 }
742
743 /*
744 * Setup relayd connections for a tracing session. First creates the socket to
745 * the relayd and send them to the right domain consumer. Consumer type MUST be
746 * network.
747 */
748 int cmd_setup_relayd(struct ltt_session *session)
749 {
750 int ret = LTTNG_OK;
751 struct ltt_ust_session *usess;
752 struct ltt_kernel_session *ksess;
753 struct consumer_socket *socket;
754 struct lttng_ht_iter iter;
755
756 assert(session);
757
758 usess = session->ust_session;
759 ksess = session->kernel_session;
760
761 DBG("Setting relayd for session %s", session->name);
762
763 rcu_read_lock();
764
765 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
766 && usess->consumer->enabled) {
767 /* For each consumer socket, send relayd sockets */
768 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
769 socket, node.node) {
770 pthread_mutex_lock(socket->lock);
771 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
772 usess->consumer, socket,
773 session->name, session->hostname,
774 session->live_timer);
775 pthread_mutex_unlock(socket->lock);
776 if (ret != LTTNG_OK) {
777 goto error;
778 }
779 /* Session is now ready for network streaming. */
780 session->net_handle = 1;
781 }
782 }
783
784 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
785 && ksess->consumer->enabled) {
786 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
787 socket, node.node) {
788 pthread_mutex_lock(socket->lock);
789 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
790 ksess->consumer, socket,
791 session->name, session->hostname,
792 session->live_timer);
793 pthread_mutex_unlock(socket->lock);
794 if (ret != LTTNG_OK) {
795 goto error;
796 }
797 /* Session is now ready for network streaming. */
798 session->net_handle = 1;
799 }
800 }
801
802 error:
803 rcu_read_unlock();
804 return ret;
805 }
806
807 /*
808 * Start a kernel session by opening all necessary streams.
809 */
810 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
811 {
812 int ret;
813 struct ltt_kernel_channel *kchan;
814
815 /* Open kernel metadata */
816 if (ksess->metadata == NULL && ksess->output_traces) {
817 ret = kernel_open_metadata(ksess);
818 if (ret < 0) {
819 ret = LTTNG_ERR_KERN_META_FAIL;
820 goto error;
821 }
822 }
823
824 /* Open kernel metadata stream */
825 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
826 ret = kernel_open_metadata_stream(ksess);
827 if (ret < 0) {
828 ERR("Kernel create metadata stream failed");
829 ret = LTTNG_ERR_KERN_STREAM_FAIL;
830 goto error;
831 }
832 }
833
834 /* For each channel */
835 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
836 if (kchan->stream_count == 0) {
837 ret = kernel_open_channel_stream(kchan);
838 if (ret < 0) {
839 ret = LTTNG_ERR_KERN_STREAM_FAIL;
840 goto error;
841 }
842 /* Update the stream global counter */
843 ksess->stream_count_global += ret;
844 }
845 }
846
847 /* Setup kernel consumer socket and send fds to it */
848 ret = init_kernel_tracing(ksess);
849 if (ret != 0) {
850 ret = LTTNG_ERR_KERN_START_FAIL;
851 goto error;
852 }
853
854 /* This start the kernel tracing */
855 ret = kernel_start_session(ksess);
856 if (ret < 0) {
857 ret = LTTNG_ERR_KERN_START_FAIL;
858 goto error;
859 }
860
861 /* Quiescent wait after starting trace */
862 kernel_wait_quiescent(kernel_tracer_fd);
863
864 ksess->active = 1;
865
866 ret = LTTNG_OK;
867
868 error:
869 return ret;
870 }
871
872 /*
873 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
874 */
875 int cmd_disable_channel(struct ltt_session *session, int domain,
876 char *channel_name)
877 {
878 int ret;
879 struct ltt_ust_session *usess;
880
881 usess = session->ust_session;
882
883 rcu_read_lock();
884
885 switch (domain) {
886 case LTTNG_DOMAIN_KERNEL:
887 {
888 ret = channel_kernel_disable(session->kernel_session,
889 channel_name);
890 if (ret != LTTNG_OK) {
891 goto error;
892 }
893
894 kernel_wait_quiescent(kernel_tracer_fd);
895 break;
896 }
897 case LTTNG_DOMAIN_UST:
898 {
899 struct ltt_ust_channel *uchan;
900 struct lttng_ht *chan_ht;
901
902 chan_ht = usess->domain_global.channels;
903
904 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
905 if (uchan == NULL) {
906 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
907 goto error;
908 }
909
910 ret = channel_ust_disable(usess, uchan);
911 if (ret != LTTNG_OK) {
912 goto error;
913 }
914 break;
915 }
916 default:
917 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
918 goto error;
919 }
920
921 ret = LTTNG_OK;
922
923 error:
924 rcu_read_unlock();
925 return ret;
926 }
927
928 /*
929 * Command LTTNG_TRACK_PID processed by the client thread.
930 *
931 * Called with session lock held.
932 */
933 int cmd_track_pid(struct ltt_session *session, int domain, int pid)
934 {
935 int ret;
936
937 rcu_read_lock();
938
939 switch (domain) {
940 case LTTNG_DOMAIN_KERNEL:
941 {
942 struct ltt_kernel_session *ksess;
943
944 ksess = session->kernel_session;
945
946 ret = kernel_track_pid(ksess, pid);
947 if (ret != LTTNG_OK) {
948 goto error;
949 }
950
951 kernel_wait_quiescent(kernel_tracer_fd);
952 break;
953 }
954 case LTTNG_DOMAIN_UST:
955 {
956 struct ltt_ust_session *usess;
957
958 usess = session->ust_session;
959
960 ret = trace_ust_track_pid(usess, pid);
961 if (ret != LTTNG_OK) {
962 goto error;
963 }
964 break;
965 }
966 default:
967 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
968 goto error;
969 }
970
971 ret = LTTNG_OK;
972
973 error:
974 rcu_read_unlock();
975 return ret;
976 }
977
978 /*
979 * Command LTTNG_UNTRACK_PID processed by the client thread.
980 *
981 * Called with session lock held.
982 */
983 int cmd_untrack_pid(struct ltt_session *session, int domain, int pid)
984 {
985 int ret;
986
987 rcu_read_lock();
988
989 switch (domain) {
990 case LTTNG_DOMAIN_KERNEL:
991 {
992 struct ltt_kernel_session *ksess;
993
994 ksess = session->kernel_session;
995
996 ret = kernel_untrack_pid(ksess, pid);
997 if (ret != LTTNG_OK) {
998 goto error;
999 }
1000
1001 kernel_wait_quiescent(kernel_tracer_fd);
1002 break;
1003 }
1004 case LTTNG_DOMAIN_UST:
1005 {
1006 struct ltt_ust_session *usess;
1007
1008 usess = session->ust_session;
1009
1010 ret = trace_ust_untrack_pid(usess, pid);
1011 if (ret != LTTNG_OK) {
1012 goto error;
1013 }
1014 break;
1015 }
1016 default:
1017 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1018 goto error;
1019 }
1020
1021 ret = LTTNG_OK;
1022
1023 error:
1024 rcu_read_unlock();
1025 return ret;
1026 }
1027
1028 /*
1029 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1030 *
1031 * The wpipe arguments is used as a notifier for the kernel thread.
1032 */
1033 int cmd_enable_channel(struct ltt_session *session,
1034 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1035 {
1036 int ret;
1037 struct ltt_ust_session *usess = session->ust_session;
1038 struct lttng_ht *chan_ht;
1039 size_t len;
1040
1041 assert(session);
1042 assert(attr);
1043 assert(domain);
1044
1045 len = strnlen(attr->name, sizeof(attr->name));
1046
1047 /* Validate channel name */
1048 if (attr->name[0] == '.' ||
1049 memchr(attr->name, '/', len) != NULL) {
1050 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1051 goto end;
1052 }
1053
1054 DBG("Enabling channel %s for session %s", attr->name, session->name);
1055
1056 rcu_read_lock();
1057
1058 /*
1059 * Don't try to enable a channel if the session has been started at
1060 * some point in time before. The tracer does not allow it.
1061 */
1062 if (session->has_been_started) {
1063 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1064 goto error;
1065 }
1066
1067 /*
1068 * If the session is a live session, remove the switch timer, the
1069 * live timer does the same thing but sends also synchronisation
1070 * beacons for inactive streams.
1071 */
1072 if (session->live_timer > 0) {
1073 attr->attr.live_timer_interval = session->live_timer;
1074 attr->attr.switch_timer_interval = 0;
1075 }
1076
1077 /*
1078 * The ringbuffer (both in user space and kernel) behave badly in overwrite
1079 * mode and with less than 2 subbuf so block it right away and send back an
1080 * invalid attribute error.
1081 */
1082 if (attr->attr.overwrite && attr->attr.num_subbuf < 2) {
1083 ret = LTTNG_ERR_INVALID;
1084 goto error;
1085 }
1086
1087 switch (domain->type) {
1088 case LTTNG_DOMAIN_KERNEL:
1089 {
1090 struct ltt_kernel_channel *kchan;
1091
1092 kchan = trace_kernel_get_channel_by_name(attr->name,
1093 session->kernel_session);
1094 if (kchan == NULL) {
1095 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1096 if (attr->name[0] != '\0') {
1097 session->kernel_session->has_non_default_channel = 1;
1098 }
1099 } else {
1100 ret = channel_kernel_enable(session->kernel_session, kchan);
1101 }
1102
1103 if (ret != LTTNG_OK) {
1104 goto error;
1105 }
1106
1107 kernel_wait_quiescent(kernel_tracer_fd);
1108 break;
1109 }
1110 case LTTNG_DOMAIN_UST:
1111 case LTTNG_DOMAIN_JUL:
1112 case LTTNG_DOMAIN_LOG4J:
1113 case LTTNG_DOMAIN_PYTHON:
1114 {
1115 struct ltt_ust_channel *uchan;
1116
1117 /*
1118 * FIXME
1119 *
1120 * Current agent implementation limitations force us to allow
1121 * only one channel at once in "agent" subdomains. Each
1122 * subdomain has a default channel name which must be strictly
1123 * adhered to.
1124 */
1125 if (domain->type == LTTNG_DOMAIN_JUL) {
1126 if (strncmp(attr->name, DEFAULT_JUL_CHANNEL_NAME,
1127 LTTNG_SYMBOL_NAME_LEN)) {
1128 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1129 goto error;
1130 }
1131 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1132 if (strncmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME,
1133 LTTNG_SYMBOL_NAME_LEN)) {
1134 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1135 goto error;
1136 }
1137 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1138 if (strncmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME,
1139 LTTNG_SYMBOL_NAME_LEN)) {
1140 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1141 goto error;
1142 }
1143 }
1144
1145 chan_ht = usess->domain_global.channels;
1146
1147 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1148 if (uchan == NULL) {
1149 ret = channel_ust_create(usess, attr, domain->buf_type);
1150 if (attr->name[0] != '\0') {
1151 usess->has_non_default_channel = 1;
1152 }
1153 } else {
1154 ret = channel_ust_enable(usess, uchan);
1155 }
1156 break;
1157 }
1158 default:
1159 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1160 goto error;
1161 }
1162
1163 error:
1164 rcu_read_unlock();
1165 end:
1166 return ret;
1167 }
1168
1169 /*
1170 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1171 */
1172 int cmd_disable_event(struct ltt_session *session, int domain,
1173 char *channel_name,
1174 struct lttng_event *event)
1175 {
1176 int ret;
1177 char *event_name;
1178
1179 DBG("Disable event command for event \'%s\'", event->name);
1180
1181 event_name = event->name;
1182 if (validate_event_name(event_name)) {
1183 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1184 goto error;
1185 }
1186
1187 /* Error out on unhandled search criteria */
1188 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1189 || event->pid || event->filter || event->exclusion) {
1190 ret = LTTNG_ERR_UNK;
1191 goto error;
1192 }
1193
1194 rcu_read_lock();
1195
1196 switch (domain) {
1197 case LTTNG_DOMAIN_KERNEL:
1198 {
1199 struct ltt_kernel_channel *kchan;
1200 struct ltt_kernel_session *ksess;
1201
1202 ksess = session->kernel_session;
1203
1204 /*
1205 * If a non-default channel has been created in the
1206 * session, explicitely require that -c chan_name needs
1207 * to be provided.
1208 */
1209 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1210 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1211 goto error_unlock;
1212 }
1213
1214 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1215 if (kchan == NULL) {
1216 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1217 goto error_unlock;
1218 }
1219
1220 switch (event->type) {
1221 case LTTNG_EVENT_ALL:
1222 ret = event_kernel_disable_event_all(kchan);
1223 if (ret != LTTNG_OK) {
1224 goto error_unlock;
1225 }
1226 break;
1227 case LTTNG_EVENT_TRACEPOINT: /* fall-through */
1228 case LTTNG_EVENT_SYSCALL:
1229 if (!strcmp(event_name, "*")) {
1230 ret = event_kernel_disable_event_type(kchan,
1231 event->type);
1232 } else {
1233 ret = event_kernel_disable_event(kchan,
1234 event_name);
1235 }
1236 if (ret != LTTNG_OK) {
1237 goto error_unlock;
1238 }
1239 break;
1240 case LTTNG_EVENT_PROBE:
1241 case LTTNG_EVENT_FUNCTION:
1242 case LTTNG_EVENT_FUNCTION_ENTRY:
1243 ret = event_kernel_disable_event(kchan, event_name);
1244 if (ret != LTTNG_OK) {
1245 goto error_unlock;
1246 }
1247 break;
1248 default:
1249 ret = LTTNG_ERR_UNK;
1250 goto error_unlock;
1251 }
1252
1253 kernel_wait_quiescent(kernel_tracer_fd);
1254 break;
1255 }
1256 case LTTNG_DOMAIN_UST:
1257 {
1258 struct ltt_ust_channel *uchan;
1259 struct ltt_ust_session *usess;
1260
1261 usess = session->ust_session;
1262
1263 if (validate_ust_event_name(event_name)) {
1264 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1265 goto error_unlock;
1266 }
1267
1268 /*
1269 * If a non-default channel has been created in the
1270 * session, explicitely require that -c chan_name needs
1271 * to be provided.
1272 */
1273 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1274 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1275 goto error_unlock;
1276 }
1277
1278 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1279 channel_name);
1280 if (uchan == NULL) {
1281 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1282 goto error_unlock;
1283 }
1284
1285 switch (event->type) {
1286 case LTTNG_EVENT_ALL:
1287 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
1288 if (ret != LTTNG_OK) {
1289 goto error_unlock;
1290 }
1291 break;
1292 default:
1293 ret = LTTNG_ERR_UNK;
1294 goto error_unlock;
1295 }
1296
1297 DBG3("Disable UST event %s in channel %s completed", event_name,
1298 channel_name);
1299 break;
1300 }
1301 case LTTNG_DOMAIN_LOG4J:
1302 case LTTNG_DOMAIN_JUL:
1303 case LTTNG_DOMAIN_PYTHON:
1304 {
1305 struct agent *agt;
1306 struct ltt_ust_session *usess = session->ust_session;
1307
1308 assert(usess);
1309
1310 switch (event->type) {
1311 case LTTNG_EVENT_ALL:
1312 break;
1313 default:
1314 ret = LTTNG_ERR_UNK;
1315 goto error_unlock;
1316 }
1317
1318 agt = trace_ust_find_agent(usess, domain);
1319 if (!agt) {
1320 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1321 goto error_unlock;
1322 }
1323 /* The wild card * means that everything should be disabled. */
1324 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1325 ret = event_agent_disable_all(usess, agt);
1326 } else {
1327 ret = event_agent_disable(usess, agt, event_name);
1328 }
1329 if (ret != LTTNG_OK) {
1330 goto error_unlock;
1331 }
1332
1333 break;
1334 }
1335 default:
1336 ret = LTTNG_ERR_UND;
1337 goto error_unlock;
1338 }
1339
1340 ret = LTTNG_OK;
1341
1342 error_unlock:
1343 rcu_read_unlock();
1344 error:
1345 return ret;
1346 }
1347
1348 /*
1349 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1350 */
1351 int cmd_add_context(struct ltt_session *session, int domain,
1352 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1353 {
1354 int ret, chan_kern_created = 0, chan_ust_created = 0;
1355
1356 switch (domain) {
1357 case LTTNG_DOMAIN_KERNEL:
1358 assert(session->kernel_session);
1359
1360 if (session->kernel_session->channel_count == 0) {
1361 /* Create default channel */
1362 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1363 if (ret != LTTNG_OK) {
1364 goto error;
1365 }
1366 chan_kern_created = 1;
1367 }
1368 /* Add kernel context to kernel tracer */
1369 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1370 if (ret != LTTNG_OK) {
1371 goto error;
1372 }
1373 break;
1374 case LTTNG_DOMAIN_UST:
1375 {
1376 struct ltt_ust_session *usess = session->ust_session;
1377 unsigned int chan_count;
1378
1379 assert(usess);
1380
1381 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1382 if (chan_count == 0) {
1383 struct lttng_channel *attr;
1384 /* Create default channel */
1385 attr = channel_new_default_attr(domain, usess->buffer_type);
1386 if (attr == NULL) {
1387 ret = LTTNG_ERR_FATAL;
1388 goto error;
1389 }
1390
1391 ret = channel_ust_create(usess, attr, usess->buffer_type);
1392 if (ret != LTTNG_OK) {
1393 free(attr);
1394 goto error;
1395 }
1396 free(attr);
1397 chan_ust_created = 1;
1398 }
1399
1400 ret = context_ust_add(usess, domain, ctx, channel_name);
1401 if (ret != LTTNG_OK) {
1402 goto error;
1403 }
1404 break;
1405 }
1406 default:
1407 ret = LTTNG_ERR_UND;
1408 goto error;
1409 }
1410
1411 return LTTNG_OK;
1412
1413 error:
1414 if (chan_kern_created) {
1415 struct ltt_kernel_channel *kchan =
1416 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1417 session->kernel_session);
1418 /* Created previously, this should NOT fail. */
1419 assert(kchan);
1420 kernel_destroy_channel(kchan);
1421 }
1422
1423 if (chan_ust_created) {
1424 struct ltt_ust_channel *uchan =
1425 trace_ust_find_channel_by_name(
1426 session->ust_session->domain_global.channels,
1427 DEFAULT_CHANNEL_NAME);
1428 /* Created previously, this should NOT fail. */
1429 assert(uchan);
1430 /* Remove from the channel list of the session. */
1431 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1432 uchan);
1433 trace_ust_destroy_channel(uchan);
1434 }
1435 return ret;
1436 }
1437
1438 static int validate_event_name(const char *name)
1439 {
1440 int ret = 0;
1441 const char *c = name;
1442 const char *event_name_end = c + LTTNG_SYMBOL_NAME_LEN;
1443
1444 /*
1445 * Make sure that unescaped wildcards are only used as the last
1446 * character of the event name.
1447 */
1448 while (c < event_name_end) {
1449 switch (*c) {
1450 case '\0':
1451 goto end;
1452 case '\\':
1453 c++;
1454 break;
1455 case '*':
1456 if ((c + 1) < event_name_end && *(c + 1)) {
1457 /* Wildcard is not the last character */
1458 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1459 goto end;
1460 }
1461 default:
1462 break;
1463 }
1464 c++;
1465 }
1466 end:
1467 return ret;
1468 }
1469
1470 static inline bool name_starts_with(const char *name, const char *prefix)
1471 {
1472 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1473
1474 return !strncmp(name, prefix, max_cmp_len);
1475 }
1476
1477 /* Perform userspace-specific event name validation */
1478 static int validate_ust_event_name(const char *name)
1479 {
1480 int ret = 0;
1481
1482 if (!name) {
1483 ret = -1;
1484 goto end;
1485 }
1486
1487 /*
1488 * Check name against all internal UST event component namespaces used
1489 * by the agents.
1490 */
1491 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1492 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1493 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1494 ret = -1;
1495 }
1496
1497 end:
1498 return ret;
1499 }
1500
1501 /*
1502 * Internal version of cmd_enable_event() with a supplemental
1503 * "internal_event" flag which is used to enable internal events which should
1504 * be hidden from clients. Such events are used in the agent implementation to
1505 * enable the events through which all "agent" events are funeled.
1506 */
1507 static int _cmd_enable_event(struct ltt_session *session,
1508 struct lttng_domain *domain,
1509 char *channel_name, struct lttng_event *event,
1510 char *filter_expression,
1511 struct lttng_filter_bytecode *filter,
1512 struct lttng_event_exclusion *exclusion,
1513 int wpipe, bool internal_event)
1514 {
1515 int ret, channel_created = 0;
1516 struct lttng_channel *attr;
1517
1518 assert(session);
1519 assert(event);
1520 assert(channel_name);
1521
1522 DBG("Enable event command for event \'%s\'", event->name);
1523
1524 rcu_read_lock();
1525
1526 ret = validate_event_name(event->name);
1527 if (ret) {
1528 goto error;
1529 }
1530
1531 switch (domain->type) {
1532 case LTTNG_DOMAIN_KERNEL:
1533 {
1534 struct ltt_kernel_channel *kchan;
1535
1536 /*
1537 * If a non-default channel has been created in the
1538 * session, explicitely require that -c chan_name needs
1539 * to be provided.
1540 */
1541 if (session->kernel_session->has_non_default_channel
1542 && channel_name[0] == '\0') {
1543 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1544 goto error;
1545 }
1546
1547 kchan = trace_kernel_get_channel_by_name(channel_name,
1548 session->kernel_session);
1549 if (kchan == NULL) {
1550 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1551 LTTNG_BUFFER_GLOBAL);
1552 if (attr == NULL) {
1553 ret = LTTNG_ERR_FATAL;
1554 goto error;
1555 }
1556 strncpy(attr->name, channel_name, sizeof(attr->name));
1557
1558 ret = cmd_enable_channel(session, domain, attr, wpipe);
1559 if (ret != LTTNG_OK) {
1560 free(attr);
1561 goto error;
1562 }
1563 free(attr);
1564
1565 channel_created = 1;
1566 }
1567
1568 /* Get the newly created kernel channel pointer */
1569 kchan = trace_kernel_get_channel_by_name(channel_name,
1570 session->kernel_session);
1571 if (kchan == NULL) {
1572 /* This sould not happen... */
1573 ret = LTTNG_ERR_FATAL;
1574 goto error;
1575 }
1576
1577 switch (event->type) {
1578 case LTTNG_EVENT_ALL:
1579 {
1580 char *filter_expression_a = NULL;
1581 struct lttng_filter_bytecode *filter_a = NULL;
1582
1583 /*
1584 * We need to duplicate filter_expression and filter,
1585 * because ownership is passed to first enable
1586 * event.
1587 */
1588 if (filter_expression) {
1589 filter_expression_a = strdup(filter_expression);
1590 if (!filter_expression_a) {
1591 ret = LTTNG_ERR_FATAL;
1592 goto error;
1593 }
1594 }
1595 if (filter) {
1596 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
1597 if (!filter_a) {
1598 free(filter_expression_a);
1599 ret = LTTNG_ERR_FATAL;
1600 goto error;
1601 }
1602 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
1603 }
1604 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
1605 ret = event_kernel_enable_event(kchan, event,
1606 filter_expression, filter);
1607 /* We have passed ownership */
1608 filter_expression = NULL;
1609 filter = NULL;
1610 if (ret != LTTNG_OK) {
1611 if (channel_created) {
1612 /* Let's not leak a useless channel. */
1613 kernel_destroy_channel(kchan);
1614 }
1615 free(filter_expression_a);
1616 free(filter_a);
1617 goto error;
1618 }
1619 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
1620 ret = event_kernel_enable_event(kchan, event,
1621 filter_expression_a, filter_a);
1622 /* We have passed ownership */
1623 filter_expression_a = NULL;
1624 filter_a = NULL;
1625 if (ret != LTTNG_OK) {
1626 goto error;
1627 }
1628 break;
1629 }
1630 case LTTNG_EVENT_PROBE:
1631 case LTTNG_EVENT_FUNCTION:
1632 case LTTNG_EVENT_FUNCTION_ENTRY:
1633 case LTTNG_EVENT_TRACEPOINT:
1634 ret = event_kernel_enable_event(kchan, event,
1635 filter_expression, filter);
1636 /* We have passed ownership */
1637 filter_expression = NULL;
1638 filter = NULL;
1639 if (ret != LTTNG_OK) {
1640 if (channel_created) {
1641 /* Let's not leak a useless channel. */
1642 kernel_destroy_channel(kchan);
1643 }
1644 goto error;
1645 }
1646 break;
1647 case LTTNG_EVENT_SYSCALL:
1648 ret = event_kernel_enable_event(kchan, event,
1649 filter_expression, filter);
1650 /* We have passed ownership */
1651 filter_expression = NULL;
1652 filter = NULL;
1653 if (ret != LTTNG_OK) {
1654 goto error;
1655 }
1656 break;
1657 default:
1658 ret = LTTNG_ERR_UNK;
1659 goto error;
1660 }
1661
1662 kernel_wait_quiescent(kernel_tracer_fd);
1663 break;
1664 }
1665 case LTTNG_DOMAIN_UST:
1666 {
1667 struct ltt_ust_channel *uchan;
1668 struct ltt_ust_session *usess = session->ust_session;
1669
1670 assert(usess);
1671
1672 /*
1673 * If a non-default channel has been created in the
1674 * session, explicitely require that -c chan_name needs
1675 * to be provided.
1676 */
1677 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1678 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1679 goto error;
1680 }
1681
1682 /* Get channel from global UST domain */
1683 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1684 channel_name);
1685 if (uchan == NULL) {
1686 /* Create default channel */
1687 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1688 usess->buffer_type);
1689 if (attr == NULL) {
1690 ret = LTTNG_ERR_FATAL;
1691 goto error;
1692 }
1693 strncpy(attr->name, channel_name, sizeof(attr->name));
1694
1695 ret = cmd_enable_channel(session, domain, attr, wpipe);
1696 if (ret != LTTNG_OK) {
1697 free(attr);
1698 goto error;
1699 }
1700 free(attr);
1701
1702 /* Get the newly created channel reference back */
1703 uchan = trace_ust_find_channel_by_name(
1704 usess->domain_global.channels, channel_name);
1705 assert(uchan);
1706 }
1707
1708 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
1709 /*
1710 * Don't allow users to add UST events to channels which
1711 * are assigned to a userspace subdomain (JUL, Log4J,
1712 * Python, etc.).
1713 */
1714 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
1715 goto error;
1716 }
1717
1718 if (!internal_event) {
1719 /*
1720 * Ensure the event name is not reserved for internal
1721 * use.
1722 */
1723 ret = validate_ust_event_name(event->name);
1724 if (ret) {
1725 WARN("Userspace event name %s failed validation.",
1726 event->name ?
1727 event->name : "NULL");
1728 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1729 goto error;
1730 }
1731 }
1732
1733 /* At this point, the session and channel exist on the tracer */
1734 ret = event_ust_enable_tracepoint(usess, uchan, event,
1735 filter_expression, filter, exclusion,
1736 internal_event);
1737 /* We have passed ownership */
1738 filter_expression = NULL;
1739 filter = NULL;
1740 exclusion = NULL;
1741 if (ret != LTTNG_OK) {
1742 goto error;
1743 }
1744 break;
1745 }
1746 case LTTNG_DOMAIN_LOG4J:
1747 case LTTNG_DOMAIN_JUL:
1748 case LTTNG_DOMAIN_PYTHON:
1749 {
1750 const char *default_event_name, *default_chan_name;
1751 struct agent *agt;
1752 struct lttng_event uevent;
1753 struct lttng_domain tmp_dom;
1754 struct ltt_ust_session *usess = session->ust_session;
1755
1756 assert(usess);
1757
1758 agt = trace_ust_find_agent(usess, domain->type);
1759 if (!agt) {
1760 agt = agent_create(domain->type);
1761 if (!agt) {
1762 ret = LTTNG_ERR_NOMEM;
1763 goto error;
1764 }
1765 agent_add(agt, usess->agents);
1766 }
1767
1768 /* Create the default tracepoint. */
1769 memset(&uevent, 0, sizeof(uevent));
1770 uevent.type = LTTNG_EVENT_TRACEPOINT;
1771 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
1772 default_event_name = event_get_default_agent_ust_name(
1773 domain->type);
1774 if (!default_event_name) {
1775 ret = LTTNG_ERR_FATAL;
1776 goto error;
1777 }
1778 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
1779 uevent.name[sizeof(uevent.name) - 1] = '\0';
1780
1781 /*
1782 * The domain type is changed because we are about to enable the
1783 * default channel and event for the JUL domain that are hardcoded.
1784 * This happens in the UST domain.
1785 */
1786 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
1787 tmp_dom.type = LTTNG_DOMAIN_UST;
1788
1789 switch (domain->type) {
1790 case LTTNG_DOMAIN_LOG4J:
1791 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
1792 break;
1793 case LTTNG_DOMAIN_JUL:
1794 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
1795 break;
1796 case LTTNG_DOMAIN_PYTHON:
1797 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
1798 break;
1799 default:
1800 /* The switch/case we are in should avoid this else big problem */
1801 assert(0);
1802 }
1803
1804 {
1805 char *filter_expression_copy = NULL;
1806 struct lttng_filter_bytecode *filter_copy = NULL;
1807
1808 if (filter) {
1809 const size_t filter_size = sizeof(
1810 struct lttng_filter_bytecode)
1811 + filter->len;
1812
1813 filter_copy = zmalloc(filter_size);
1814 if (!filter_copy) {
1815 ret = LTTNG_ERR_NOMEM;
1816 goto error;
1817 }
1818 memcpy(filter_copy, filter, filter_size);
1819
1820 filter_expression_copy =
1821 strdup(filter_expression);
1822 if (!filter_expression) {
1823 ret = LTTNG_ERR_NOMEM;
1824 }
1825
1826 if (!filter_expression_copy || !filter_copy) {
1827 free(filter_expression_copy);
1828 free(filter_copy);
1829 goto error;
1830 }
1831 }
1832
1833 ret = cmd_enable_event_internal(session, &tmp_dom,
1834 (char *) default_chan_name,
1835 &uevent, filter_expression_copy,
1836 filter_copy, NULL, wpipe);
1837 }
1838
1839 if (ret != LTTNG_OK && ret != LTTNG_ERR_UST_EVENT_ENABLED) {
1840 goto error;
1841 }
1842
1843 /* The wild card * means that everything should be enabled. */
1844 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1845 ret = event_agent_enable_all(usess, agt, event, filter,
1846 filter_expression);
1847 } else {
1848 ret = event_agent_enable(usess, agt, event, filter,
1849 filter_expression);
1850 }
1851 filter = NULL;
1852 filter_expression = NULL;
1853 if (ret != LTTNG_OK) {
1854 goto error;
1855 }
1856
1857 break;
1858 }
1859 default:
1860 ret = LTTNG_ERR_UND;
1861 goto error;
1862 }
1863
1864 ret = LTTNG_OK;
1865
1866 error:
1867 free(filter_expression);
1868 free(filter);
1869 free(exclusion);
1870 rcu_read_unlock();
1871 return ret;
1872 }
1873
1874 /*
1875 * Command LTTNG_ENABLE_EVENT processed by the client thread.
1876 * We own filter, exclusion, and filter_expression.
1877 */
1878 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1879 char *channel_name, struct lttng_event *event,
1880 char *filter_expression,
1881 struct lttng_filter_bytecode *filter,
1882 struct lttng_event_exclusion *exclusion,
1883 int wpipe)
1884 {
1885 return _cmd_enable_event(session, domain, channel_name, event,
1886 filter_expression, filter, exclusion, wpipe, false);
1887 }
1888
1889 /*
1890 * Enable an event which is internal to LTTng. An internal should
1891 * never be made visible to clients and are immune to checks such as
1892 * reserved names.
1893 */
1894 static int cmd_enable_event_internal(struct ltt_session *session,
1895 struct lttng_domain *domain,
1896 char *channel_name, struct lttng_event *event,
1897 char *filter_expression,
1898 struct lttng_filter_bytecode *filter,
1899 struct lttng_event_exclusion *exclusion,
1900 int wpipe)
1901 {
1902 return _cmd_enable_event(session, domain, channel_name, event,
1903 filter_expression, filter, exclusion, wpipe, true);
1904 }
1905
1906 /*
1907 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1908 */
1909 ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
1910 {
1911 int ret;
1912 ssize_t nb_events = 0;
1913
1914 switch (domain) {
1915 case LTTNG_DOMAIN_KERNEL:
1916 nb_events = kernel_list_events(kernel_tracer_fd, events);
1917 if (nb_events < 0) {
1918 ret = LTTNG_ERR_KERN_LIST_FAIL;
1919 goto error;
1920 }
1921 break;
1922 case LTTNG_DOMAIN_UST:
1923 nb_events = ust_app_list_events(events);
1924 if (nb_events < 0) {
1925 ret = LTTNG_ERR_UST_LIST_FAIL;
1926 goto error;
1927 }
1928 break;
1929 case LTTNG_DOMAIN_LOG4J:
1930 case LTTNG_DOMAIN_JUL:
1931 case LTTNG_DOMAIN_PYTHON:
1932 nb_events = agent_list_events(events, domain);
1933 if (nb_events < 0) {
1934 ret = LTTNG_ERR_UST_LIST_FAIL;
1935 goto error;
1936 }
1937 break;
1938 default:
1939 ret = LTTNG_ERR_UND;
1940 goto error;
1941 }
1942
1943 return nb_events;
1944
1945 error:
1946 /* Return negative value to differentiate return code */
1947 return -ret;
1948 }
1949
1950 /*
1951 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1952 */
1953 ssize_t cmd_list_tracepoint_fields(int domain,
1954 struct lttng_event_field **fields)
1955 {
1956 int ret;
1957 ssize_t nb_fields = 0;
1958
1959 switch (domain) {
1960 case LTTNG_DOMAIN_UST:
1961 nb_fields = ust_app_list_event_fields(fields);
1962 if (nb_fields < 0) {
1963 ret = LTTNG_ERR_UST_LIST_FAIL;
1964 goto error;
1965 }
1966 break;
1967 case LTTNG_DOMAIN_KERNEL:
1968 default: /* fall-through */
1969 ret = LTTNG_ERR_UND;
1970 goto error;
1971 }
1972
1973 return nb_fields;
1974
1975 error:
1976 /* Return negative value to differentiate return code */
1977 return -ret;
1978 }
1979
1980 ssize_t cmd_list_syscalls(struct lttng_event **events)
1981 {
1982 return syscall_table_list(events);
1983 }
1984
1985 /*
1986 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
1987 *
1988 * Called with session lock held.
1989 */
1990 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
1991 int domain, int32_t **pids)
1992 {
1993 int ret;
1994 ssize_t nr_pids = 0;
1995
1996 switch (domain) {
1997 case LTTNG_DOMAIN_KERNEL:
1998 {
1999 struct ltt_kernel_session *ksess;
2000
2001 ksess = session->kernel_session;
2002 nr_pids = kernel_list_tracker_pids(ksess, pids);
2003 if (nr_pids < 0) {
2004 ret = LTTNG_ERR_KERN_LIST_FAIL;
2005 goto error;
2006 }
2007 break;
2008 }
2009 case LTTNG_DOMAIN_UST:
2010 {
2011 struct ltt_ust_session *usess;
2012
2013 usess = session->ust_session;
2014 nr_pids = trace_ust_list_tracker_pids(usess, pids);
2015 if (nr_pids < 0) {
2016 ret = LTTNG_ERR_UST_LIST_FAIL;
2017 goto error;
2018 }
2019 break;
2020 }
2021 case LTTNG_DOMAIN_LOG4J:
2022 case LTTNG_DOMAIN_JUL:
2023 case LTTNG_DOMAIN_PYTHON:
2024 default:
2025 ret = LTTNG_ERR_UND;
2026 goto error;
2027 }
2028
2029 return nr_pids;
2030
2031 error:
2032 /* Return negative value to differentiate return code */
2033 return -ret;
2034 }
2035
2036 /*
2037 * Command LTTNG_START_TRACE processed by the client thread.
2038 *
2039 * Called with session mutex held.
2040 */
2041 int cmd_start_trace(struct ltt_session *session)
2042 {
2043 int ret;
2044 unsigned long nb_chan = 0;
2045 struct ltt_kernel_session *ksession;
2046 struct ltt_ust_session *usess;
2047
2048 assert(session);
2049
2050 /* Ease our life a bit ;) */
2051 ksession = session->kernel_session;
2052 usess = session->ust_session;
2053
2054 /* Is the session already started? */
2055 if (session->active) {
2056 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2057 goto error;
2058 }
2059
2060 /*
2061 * Starting a session without channel is useless since after that it's not
2062 * possible to enable channel thus inform the client.
2063 */
2064 if (usess && usess->domain_global.channels) {
2065 rcu_read_lock();
2066 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2067 rcu_read_unlock();
2068 }
2069 if (ksession) {
2070 nb_chan += ksession->channel_count;
2071 }
2072 if (!nb_chan) {
2073 ret = LTTNG_ERR_NO_CHANNEL;
2074 goto error;
2075 }
2076
2077 /* Kernel tracing */
2078 if (ksession != NULL) {
2079 ret = start_kernel_session(ksession, kernel_tracer_fd);
2080 if (ret != LTTNG_OK) {
2081 goto error;
2082 }
2083 }
2084
2085 /* Flag session that trace should start automatically */
2086 if (usess) {
2087 /*
2088 * Even though the start trace might fail, flag this session active so
2089 * other application coming in are started by default.
2090 */
2091 usess->active = 1;
2092
2093 ret = ust_app_start_trace_all(usess);
2094 if (ret < 0) {
2095 ret = LTTNG_ERR_UST_START_FAIL;
2096 goto error;
2097 }
2098 }
2099
2100 /* Flag this after a successful start. */
2101 session->has_been_started = 1;
2102 session->active = 1;
2103
2104 ret = LTTNG_OK;
2105
2106 error:
2107 return ret;
2108 }
2109
2110 /*
2111 * Command LTTNG_STOP_TRACE processed by the client thread.
2112 */
2113 int cmd_stop_trace(struct ltt_session *session)
2114 {
2115 int ret;
2116 struct ltt_kernel_channel *kchan;
2117 struct ltt_kernel_session *ksession;
2118 struct ltt_ust_session *usess;
2119
2120 assert(session);
2121
2122 /* Short cut */
2123 ksession = session->kernel_session;
2124 usess = session->ust_session;
2125
2126 /* Session is not active. Skip everythong and inform the client. */
2127 if (!session->active) {
2128 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2129 goto error;
2130 }
2131
2132 /* Kernel tracer */
2133 if (ksession && ksession->active) {
2134 DBG("Stop kernel tracing");
2135
2136 /* Flush metadata if exist */
2137 if (ksession->metadata_stream_fd >= 0) {
2138 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2139 if (ret < 0) {
2140 ERR("Kernel metadata flush failed");
2141 }
2142 }
2143
2144 /* Flush all buffers before stopping */
2145 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2146 ret = kernel_flush_buffer(kchan);
2147 if (ret < 0) {
2148 ERR("Kernel flush buffer error");
2149 }
2150 }
2151
2152 ret = kernel_stop_session(ksession);
2153 if (ret < 0) {
2154 ret = LTTNG_ERR_KERN_STOP_FAIL;
2155 goto error;
2156 }
2157
2158 kernel_wait_quiescent(kernel_tracer_fd);
2159
2160 ksession->active = 0;
2161 }
2162
2163 if (usess && usess->active) {
2164 /*
2165 * Even though the stop trace might fail, flag this session inactive so
2166 * other application coming in are not started by default.
2167 */
2168 usess->active = 0;
2169
2170 ret = ust_app_stop_trace_all(usess);
2171 if (ret < 0) {
2172 ret = LTTNG_ERR_UST_STOP_FAIL;
2173 goto error;
2174 }
2175 }
2176
2177 /* Flag inactive after a successful stop. */
2178 session->active = 0;
2179 ret = LTTNG_OK;
2180
2181 error:
2182 return ret;
2183 }
2184
2185 /*
2186 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2187 */
2188 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2189 struct lttng_uri *uris)
2190 {
2191 int ret, i;
2192 struct ltt_kernel_session *ksess = session->kernel_session;
2193 struct ltt_ust_session *usess = session->ust_session;
2194
2195 assert(session);
2196 assert(uris);
2197 assert(nb_uri > 0);
2198
2199 /* Can't set consumer URI if the session is active. */
2200 if (session->active) {
2201 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2202 goto error;
2203 }
2204
2205 /* Set the "global" consumer URIs */
2206 for (i = 0; i < nb_uri; i++) {
2207 ret = add_uri_to_consumer(session->consumer,
2208 &uris[i], 0, session->name);
2209 if (ret != LTTNG_OK) {
2210 goto error;
2211 }
2212 }
2213
2214 /* Set UST session URIs */
2215 if (session->ust_session) {
2216 for (i = 0; i < nb_uri; i++) {
2217 ret = add_uri_to_consumer(
2218 session->ust_session->consumer,
2219 &uris[i], LTTNG_DOMAIN_UST,
2220 session->name);
2221 if (ret != LTTNG_OK) {
2222 goto error;
2223 }
2224 }
2225 }
2226
2227 /* Set kernel session URIs */
2228 if (session->kernel_session) {
2229 for (i = 0; i < nb_uri; i++) {
2230 ret = add_uri_to_consumer(
2231 session->kernel_session->consumer,
2232 &uris[i], LTTNG_DOMAIN_KERNEL,
2233 session->name);
2234 if (ret != LTTNG_OK) {
2235 goto error;
2236 }
2237 }
2238 }
2239
2240 /*
2241 * Make sure to set the session in output mode after we set URI since a
2242 * session can be created without URL (thus flagged in no output mode).
2243 */
2244 session->output_traces = 1;
2245 if (ksess) {
2246 ksess->output_traces = 1;
2247 }
2248
2249 if (usess) {
2250 usess->output_traces = 1;
2251 }
2252
2253 /* All good! */
2254 ret = LTTNG_OK;
2255
2256 error:
2257 return ret;
2258 }
2259
2260 /*
2261 * Command LTTNG_CREATE_SESSION processed by the client thread.
2262 */
2263 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
2264 size_t nb_uri, lttng_sock_cred *creds, unsigned int live_timer)
2265 {
2266 int ret;
2267 struct ltt_session *session;
2268
2269 assert(name);
2270 assert(creds);
2271
2272 /*
2273 * Verify if the session already exist
2274 *
2275 * XXX: There is no need for the session lock list here since the caller
2276 * (process_client_msg) is holding it. We might want to change that so a
2277 * single command does not lock the entire session list.
2278 */
2279 session = session_find_by_name(name);
2280 if (session != NULL) {
2281 ret = LTTNG_ERR_EXIST_SESS;
2282 goto find_error;
2283 }
2284
2285 /* Create tracing session in the registry */
2286 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
2287 LTTNG_SOCK_GET_GID_CRED(creds));
2288 if (ret != LTTNG_OK) {
2289 goto session_error;
2290 }
2291
2292 /*
2293 * Get the newly created session pointer back
2294 *
2295 * XXX: There is no need for the session lock list here since the caller
2296 * (process_client_msg) is holding it. We might want to change that so a
2297 * single command does not lock the entire session list.
2298 */
2299 session = session_find_by_name(name);
2300 assert(session);
2301
2302 session->live_timer = live_timer;
2303 /* Create default consumer output for the session not yet created. */
2304 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
2305 if (session->consumer == NULL) {
2306 ret = LTTNG_ERR_FATAL;
2307 goto consumer_error;
2308 }
2309
2310 if (uris) {
2311 ret = cmd_set_consumer_uri(session, nb_uri, uris);
2312 if (ret != LTTNG_OK) {
2313 goto consumer_error;
2314 }
2315 session->output_traces = 1;
2316 } else {
2317 session->output_traces = 0;
2318 DBG2("Session %s created with no output", session->name);
2319 }
2320
2321 session->consumer->enabled = 1;
2322
2323 return LTTNG_OK;
2324
2325 consumer_error:
2326 session_destroy(session);
2327 session_error:
2328 find_error:
2329 return ret;
2330 }
2331
2332 /*
2333 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
2334 */
2335 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
2336 size_t nb_uri, lttng_sock_cred *creds)
2337 {
2338 int ret;
2339 struct ltt_session *session;
2340 struct snapshot_output *new_output = NULL;
2341
2342 assert(name);
2343 assert(creds);
2344
2345 /*
2346 * Create session in no output mode with URIs set to NULL. The uris we've
2347 * received are for a default snapshot output if one.
2348 */
2349 ret = cmd_create_session_uri(name, NULL, 0, creds, 0);
2350 if (ret != LTTNG_OK) {
2351 goto error;
2352 }
2353
2354 /* Get the newly created session pointer back. This should NEVER fail. */
2355 session = session_find_by_name(name);
2356 assert(session);
2357
2358 /* Flag session for snapshot mode. */
2359 session->snapshot_mode = 1;
2360
2361 /* Skip snapshot output creation if no URI is given. */
2362 if (nb_uri == 0) {
2363 goto end;
2364 }
2365
2366 new_output = snapshot_output_alloc();
2367 if (!new_output) {
2368 ret = LTTNG_ERR_NOMEM;
2369 goto error_snapshot_alloc;
2370 }
2371
2372 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
2373 uris, nb_uri, session->consumer, new_output, &session->snapshot);
2374 if (ret < 0) {
2375 if (ret == -ENOMEM) {
2376 ret = LTTNG_ERR_NOMEM;
2377 } else {
2378 ret = LTTNG_ERR_INVALID;
2379 }
2380 goto error_snapshot;
2381 }
2382
2383 rcu_read_lock();
2384 snapshot_add_output(&session->snapshot, new_output);
2385 rcu_read_unlock();
2386
2387 end:
2388 return LTTNG_OK;
2389
2390 error_snapshot:
2391 snapshot_output_destroy(new_output);
2392 error_snapshot_alloc:
2393 session_destroy(session);
2394 error:
2395 return ret;
2396 }
2397
2398 /*
2399 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2400 *
2401 * Called with session lock held.
2402 */
2403 int cmd_destroy_session(struct ltt_session *session, int wpipe)
2404 {
2405 int ret;
2406 struct ltt_ust_session *usess;
2407 struct ltt_kernel_session *ksess;
2408
2409 /* Safety net */
2410 assert(session);
2411
2412 usess = session->ust_session;
2413 ksess = session->kernel_session;
2414
2415 /* Clean kernel session teardown */
2416 kernel_destroy_session(ksess);
2417
2418 /* UST session teardown */
2419 if (usess) {
2420 /* Close any relayd session */
2421 consumer_output_send_destroy_relayd(usess->consumer);
2422
2423 /* Destroy every UST application related to this session. */
2424 ret = ust_app_destroy_trace_all(usess);
2425 if (ret) {
2426 ERR("Error in ust_app_destroy_trace_all");
2427 }
2428
2429 /* Clean up the rest. */
2430 trace_ust_destroy_session(usess);
2431 }
2432
2433 /*
2434 * Must notify the kernel thread here to update it's poll set in order to
2435 * remove the channel(s)' fd just destroyed.
2436 */
2437 ret = notify_thread_pipe(wpipe);
2438 if (ret < 0) {
2439 PERROR("write kernel poll pipe");
2440 }
2441
2442 ret = session_destroy(session);
2443
2444 return ret;
2445 }
2446
2447 /*
2448 * Command LTTNG_CALIBRATE processed by the client thread.
2449 */
2450 int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2451 {
2452 int ret;
2453
2454 switch (domain) {
2455 case LTTNG_DOMAIN_KERNEL:
2456 {
2457 struct lttng_kernel_calibrate kcalibrate;
2458
2459 switch (calibrate->type) {
2460 case LTTNG_CALIBRATE_FUNCTION:
2461 default:
2462 /* Default and only possible calibrate option. */
2463 kcalibrate.type = LTTNG_KERNEL_CALIBRATE_KRETPROBE;
2464 break;
2465 }
2466
2467 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2468 if (ret < 0) {
2469 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
2470 goto error;
2471 }
2472 break;
2473 }
2474 case LTTNG_DOMAIN_UST:
2475 {
2476 struct lttng_ust_calibrate ucalibrate;
2477
2478 switch (calibrate->type) {
2479 case LTTNG_CALIBRATE_FUNCTION:
2480 default:
2481 /* Default and only possible calibrate option. */
2482 ucalibrate.type = LTTNG_UST_CALIBRATE_TRACEPOINT;
2483 break;
2484 }
2485
2486 ret = ust_app_calibrate_glb(&ucalibrate);
2487 if (ret < 0) {
2488 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
2489 goto error;
2490 }
2491 break;
2492 }
2493 default:
2494 ret = LTTNG_ERR_UND;
2495 goto error;
2496 }
2497
2498 ret = LTTNG_OK;
2499
2500 error:
2501 return ret;
2502 }
2503
2504 /*
2505 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2506 */
2507 int cmd_register_consumer(struct ltt_session *session, int domain,
2508 const char *sock_path, struct consumer_data *cdata)
2509 {
2510 int ret, sock;
2511 struct consumer_socket *socket = NULL;
2512
2513 assert(session);
2514 assert(cdata);
2515 assert(sock_path);
2516
2517 switch (domain) {
2518 case LTTNG_DOMAIN_KERNEL:
2519 {
2520 struct ltt_kernel_session *ksess = session->kernel_session;
2521
2522 assert(ksess);
2523
2524 /* Can't register a consumer if there is already one */
2525 if (ksess->consumer_fds_sent != 0) {
2526 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2527 goto error;
2528 }
2529
2530 sock = lttcomm_connect_unix_sock(sock_path);
2531 if (sock < 0) {
2532 ret = LTTNG_ERR_CONNECT_FAIL;
2533 goto error;
2534 }
2535 cdata->cmd_sock = sock;
2536
2537 socket = consumer_allocate_socket(&cdata->cmd_sock);
2538 if (socket == NULL) {
2539 ret = close(sock);
2540 if (ret < 0) {
2541 PERROR("close register consumer");
2542 }
2543 cdata->cmd_sock = -1;
2544 ret = LTTNG_ERR_FATAL;
2545 goto error;
2546 }
2547
2548 socket->lock = zmalloc(sizeof(pthread_mutex_t));
2549 if (socket->lock == NULL) {
2550 PERROR("zmalloc pthread mutex");
2551 ret = LTTNG_ERR_FATAL;
2552 goto error;
2553 }
2554 pthread_mutex_init(socket->lock, NULL);
2555 socket->registered = 1;
2556
2557 rcu_read_lock();
2558 consumer_add_socket(socket, ksess->consumer);
2559 rcu_read_unlock();
2560
2561 pthread_mutex_lock(&cdata->pid_mutex);
2562 cdata->pid = -1;
2563 pthread_mutex_unlock(&cdata->pid_mutex);
2564
2565 break;
2566 }
2567 default:
2568 /* TODO: Userspace tracing */
2569 ret = LTTNG_ERR_UND;
2570 goto error;
2571 }
2572
2573 return LTTNG_OK;
2574
2575 error:
2576 if (socket) {
2577 consumer_destroy_socket(socket);
2578 }
2579 return ret;
2580 }
2581
2582 /*
2583 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2584 */
2585 ssize_t cmd_list_domains(struct ltt_session *session,
2586 struct lttng_domain **domains)
2587 {
2588 int ret, index = 0;
2589 ssize_t nb_dom = 0;
2590 struct agent *agt;
2591 struct lttng_ht_iter iter;
2592
2593 if (session->kernel_session != NULL) {
2594 DBG3("Listing domains found kernel domain");
2595 nb_dom++;
2596 }
2597
2598 if (session->ust_session != NULL) {
2599 DBG3("Listing domains found UST global domain");
2600 nb_dom++;
2601
2602 rcu_read_lock();
2603 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2604 agt, node.node) {
2605 if (agt->being_used) {
2606 nb_dom++;
2607 }
2608 }
2609 rcu_read_unlock();
2610 }
2611
2612 if (!nb_dom) {
2613 goto end;
2614 }
2615
2616 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2617 if (*domains == NULL) {
2618 ret = LTTNG_ERR_FATAL;
2619 goto error;
2620 }
2621
2622 if (session->kernel_session != NULL) {
2623 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2624
2625 /* Kernel session buffer type is always GLOBAL */
2626 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
2627
2628 index++;
2629 }
2630
2631 if (session->ust_session != NULL) {
2632 (*domains)[index].type = LTTNG_DOMAIN_UST;
2633 (*domains)[index].buf_type = session->ust_session->buffer_type;
2634 index++;
2635
2636 rcu_read_lock();
2637 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2638 agt, node.node) {
2639 if (agt->being_used) {
2640 (*domains)[index].type = agt->domain;
2641 (*domains)[index].buf_type = session->ust_session->buffer_type;
2642 index++;
2643 }
2644 }
2645 rcu_read_unlock();
2646 }
2647 end:
2648 return nb_dom;
2649
2650 error:
2651 /* Return negative value to differentiate return code */
2652 return -ret;
2653 }
2654
2655
2656 /*
2657 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2658 */
2659 ssize_t cmd_list_channels(int domain, struct ltt_session *session,
2660 struct lttng_channel **channels)
2661 {
2662 int ret;
2663 ssize_t nb_chan = 0;
2664
2665 switch (domain) {
2666 case LTTNG_DOMAIN_KERNEL:
2667 if (session->kernel_session != NULL) {
2668 nb_chan = session->kernel_session->channel_count;
2669 }
2670 DBG3("Number of kernel channels %zd", nb_chan);
2671 if (nb_chan <= 0) {
2672 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
2673 }
2674 break;
2675 case LTTNG_DOMAIN_UST:
2676 if (session->ust_session != NULL) {
2677 rcu_read_lock();
2678 nb_chan = lttng_ht_get_count(
2679 session->ust_session->domain_global.channels);
2680 rcu_read_unlock();
2681 }
2682 DBG3("Number of UST global channels %zd", nb_chan);
2683 if (nb_chan < 0) {
2684 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2685 goto error;
2686 }
2687 break;
2688 default:
2689 ret = LTTNG_ERR_UND;
2690 goto error;
2691 }
2692
2693 if (nb_chan > 0) {
2694 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
2695 if (*channels == NULL) {
2696 ret = LTTNG_ERR_FATAL;
2697 goto error;
2698 }
2699
2700 list_lttng_channels(domain, session, *channels);
2701 }
2702
2703 return nb_chan;
2704
2705 error:
2706 /* Return negative value to differentiate return code */
2707 return -ret;
2708 }
2709
2710 /*
2711 * Command LTTNG_LIST_EVENTS processed by the client thread.
2712 */
2713 ssize_t cmd_list_events(int domain, struct ltt_session *session,
2714 char *channel_name, struct lttng_event **events)
2715 {
2716 int ret = 0;
2717 ssize_t nb_event = 0;
2718
2719 switch (domain) {
2720 case LTTNG_DOMAIN_KERNEL:
2721 if (session->kernel_session != NULL) {
2722 nb_event = list_lttng_kernel_events(channel_name,
2723 session->kernel_session, events);
2724 }
2725 break;
2726 case LTTNG_DOMAIN_UST:
2727 {
2728 if (session->ust_session != NULL) {
2729 nb_event = list_lttng_ust_global_events(channel_name,
2730 &session->ust_session->domain_global, events);
2731 }
2732 break;
2733 }
2734 case LTTNG_DOMAIN_LOG4J:
2735 case LTTNG_DOMAIN_JUL:
2736 case LTTNG_DOMAIN_PYTHON:
2737 if (session->ust_session) {
2738 struct lttng_ht_iter iter;
2739 struct agent *agt;
2740
2741 rcu_read_lock();
2742 cds_lfht_for_each_entry(session->ust_session->agents->ht,
2743 &iter.iter, agt, node.node) {
2744 nb_event = list_lttng_agent_events(agt, events);
2745 }
2746 rcu_read_unlock();
2747 }
2748 break;
2749 default:
2750 ret = LTTNG_ERR_UND;
2751 goto error;
2752 }
2753
2754 return nb_event;
2755
2756 error:
2757 /* Return negative value to differentiate return code */
2758 return -ret;
2759 }
2760
2761 /*
2762 * Using the session list, filled a lttng_session array to send back to the
2763 * client for session listing.
2764 *
2765 * The session list lock MUST be acquired before calling this function. Use
2766 * session_lock_list() and session_unlock_list().
2767 */
2768 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2769 gid_t gid)
2770 {
2771 int ret;
2772 unsigned int i = 0;
2773 struct ltt_session *session;
2774 struct ltt_session_list *list = session_get_list();
2775
2776 DBG("Getting all available session for UID %d GID %d",
2777 uid, gid);
2778 /*
2779 * Iterate over session list and append data after the control struct in
2780 * the buffer.
2781 */
2782 cds_list_for_each_entry(session, &list->head, list) {
2783 /*
2784 * Only list the sessions the user can control.
2785 */
2786 if (!session_access_ok(session, uid, gid)) {
2787 continue;
2788 }
2789
2790 struct ltt_kernel_session *ksess = session->kernel_session;
2791 struct ltt_ust_session *usess = session->ust_session;
2792
2793 if (session->consumer->type == CONSUMER_DST_NET ||
2794 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2795 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2796 ret = build_network_session_path(sessions[i].path,
2797 sizeof(sessions[i].path), session);
2798 } else {
2799 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
2800 session->consumer->dst.trace_path);
2801 }
2802 if (ret < 0) {
2803 PERROR("snprintf session path");
2804 continue;
2805 }
2806
2807 strncpy(sessions[i].name, session->name, NAME_MAX);
2808 sessions[i].name[NAME_MAX - 1] = '\0';
2809 sessions[i].enabled = session->active;
2810 sessions[i].snapshot_mode = session->snapshot_mode;
2811 sessions[i].live_timer_interval = session->live_timer;
2812 i++;
2813 }
2814 }
2815
2816 /*
2817 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2818 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
2819 */
2820 int cmd_data_pending(struct ltt_session *session)
2821 {
2822 int ret;
2823 struct ltt_kernel_session *ksess = session->kernel_session;
2824 struct ltt_ust_session *usess = session->ust_session;
2825
2826 assert(session);
2827
2828 /* Session MUST be stopped to ask for data availability. */
2829 if (session->active) {
2830 ret = LTTNG_ERR_SESSION_STARTED;
2831 goto error;
2832 } else {
2833 /*
2834 * If stopped, just make sure we've started before else the above call
2835 * will always send that there is data pending.
2836 *
2837 * The consumer assumes that when the data pending command is received,
2838 * the trace has been started before or else no output data is written
2839 * by the streams which is a condition for data pending. So, this is
2840 * *VERY* important that we don't ask the consumer before a start
2841 * trace.
2842 */
2843 if (!session->has_been_started) {
2844 ret = 0;
2845 goto error;
2846 }
2847 }
2848
2849 if (ksess && ksess->consumer) {
2850 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2851 if (ret == 1) {
2852 /* Data is still being extracted for the kernel. */
2853 goto error;
2854 }
2855 }
2856
2857 if (usess && usess->consumer) {
2858 ret = consumer_is_data_pending(usess->id, usess->consumer);
2859 if (ret == 1) {
2860 /* Data is still being extracted for the kernel. */
2861 goto error;
2862 }
2863 }
2864
2865 /* Data is ready to be read by a viewer */
2866 ret = 0;
2867
2868 error:
2869 return ret;
2870 }
2871
2872 /*
2873 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
2874 *
2875 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2876 */
2877 int cmd_snapshot_add_output(struct ltt_session *session,
2878 struct lttng_snapshot_output *output, uint32_t *id)
2879 {
2880 int ret;
2881 struct snapshot_output *new_output;
2882
2883 assert(session);
2884 assert(output);
2885
2886 DBG("Cmd snapshot add output for session %s", session->name);
2887
2888 /*
2889 * Permission denied to create an output if the session is not
2890 * set in no output mode.
2891 */
2892 if (session->output_traces) {
2893 ret = LTTNG_ERR_EPERM;
2894 goto error;
2895 }
2896
2897 /* Only one output is allowed until we have the "tee" feature. */
2898 if (session->snapshot.nb_output == 1) {
2899 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
2900 goto error;
2901 }
2902
2903 new_output = snapshot_output_alloc();
2904 if (!new_output) {
2905 ret = LTTNG_ERR_NOMEM;
2906 goto error;
2907 }
2908
2909 ret = snapshot_output_init(output->max_size, output->name,
2910 output->ctrl_url, output->data_url, session->consumer, new_output,
2911 &session->snapshot);
2912 if (ret < 0) {
2913 if (ret == -ENOMEM) {
2914 ret = LTTNG_ERR_NOMEM;
2915 } else {
2916 ret = LTTNG_ERR_INVALID;
2917 }
2918 goto free_error;
2919 }
2920
2921 rcu_read_lock();
2922 snapshot_add_output(&session->snapshot, new_output);
2923 if (id) {
2924 *id = new_output->id;
2925 }
2926 rcu_read_unlock();
2927
2928 return LTTNG_OK;
2929
2930 free_error:
2931 snapshot_output_destroy(new_output);
2932 error:
2933 return ret;
2934 }
2935
2936 /*
2937 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
2938 *
2939 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2940 */
2941 int cmd_snapshot_del_output(struct ltt_session *session,
2942 struct lttng_snapshot_output *output)
2943 {
2944 int ret;
2945 struct snapshot_output *sout = NULL;
2946
2947 assert(session);
2948 assert(output);
2949
2950 rcu_read_lock();
2951
2952 /*
2953 * Permission denied to create an output if the session is not
2954 * set in no output mode.
2955 */
2956 if (session->output_traces) {
2957 ret = LTTNG_ERR_EPERM;
2958 goto error;
2959 }
2960
2961 if (output->id) {
2962 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
2963 session->name);
2964 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
2965 } else if (*output->name != '\0') {
2966 DBG("Cmd snapshot del output name %s for session %s", output->name,
2967 session->name);
2968 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
2969 }
2970 if (!sout) {
2971 ret = LTTNG_ERR_INVALID;
2972 goto error;
2973 }
2974
2975 snapshot_delete_output(&session->snapshot, sout);
2976 snapshot_output_destroy(sout);
2977 ret = LTTNG_OK;
2978
2979 error:
2980 rcu_read_unlock();
2981 return ret;
2982 }
2983
2984 /*
2985 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
2986 *
2987 * If no output is available, outputs is untouched and 0 is returned.
2988 *
2989 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
2990 */
2991 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
2992 struct lttng_snapshot_output **outputs)
2993 {
2994 int ret, idx = 0;
2995 struct lttng_snapshot_output *list = NULL;
2996 struct lttng_ht_iter iter;
2997 struct snapshot_output *output;
2998
2999 assert(session);
3000 assert(outputs);
3001
3002 DBG("Cmd snapshot list outputs for session %s", session->name);
3003
3004 /*
3005 * Permission denied to create an output if the session is not
3006 * set in no output mode.
3007 */
3008 if (session->output_traces) {
3009 ret = -LTTNG_ERR_EPERM;
3010 goto error;
3011 }
3012
3013 if (session->snapshot.nb_output == 0) {
3014 ret = 0;
3015 goto error;
3016 }
3017
3018 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
3019 if (!list) {
3020 ret = -LTTNG_ERR_NOMEM;
3021 goto error;
3022 }
3023
3024 /* Copy list from session to the new list object. */
3025 rcu_read_lock();
3026 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
3027 output, node.node) {
3028 assert(output->consumer);
3029 list[idx].id = output->id;
3030 list[idx].max_size = output->max_size;
3031 strncpy(list[idx].name, output->name, sizeof(list[idx].name));
3032 if (output->consumer->type == CONSUMER_DST_LOCAL) {
3033 strncpy(list[idx].ctrl_url, output->consumer->dst.trace_path,
3034 sizeof(list[idx].ctrl_url));
3035 } else {
3036 /* Control URI. */
3037 ret = uri_to_str_url(&output->consumer->dst.net.control,
3038 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
3039 if (ret < 0) {
3040 ret = -LTTNG_ERR_NOMEM;
3041 goto error;
3042 }
3043
3044 /* Data URI. */
3045 ret = uri_to_str_url(&output->consumer->dst.net.data,
3046 list[idx].data_url, sizeof(list[idx].data_url));
3047 if (ret < 0) {
3048 ret = -LTTNG_ERR_NOMEM;
3049 goto error;
3050 }
3051 }
3052 idx++;
3053 }
3054
3055 *outputs = list;
3056 list = NULL;
3057 ret = session->snapshot.nb_output;
3058 error:
3059 free(list);
3060 rcu_read_unlock();
3061 return ret;
3062 }
3063
3064 /*
3065 * Send relayd sockets from snapshot output to consumer. Ignore request if the
3066 * snapshot output is *not* set with a remote destination.
3067 *
3068 * Return 0 on success or a LTTNG_ERR code.
3069 */
3070 static int set_relayd_for_snapshot(struct consumer_output *consumer,
3071 struct snapshot_output *snap_output, struct ltt_session *session)
3072 {
3073 int ret = LTTNG_OK;
3074 struct lttng_ht_iter iter;
3075 struct consumer_socket *socket;
3076
3077 assert(consumer);
3078 assert(snap_output);
3079 assert(session);
3080
3081 DBG2("Set relayd object from snapshot output");
3082
3083 /* Ignore if snapshot consumer output is not network. */
3084 if (snap_output->consumer->type != CONSUMER_DST_NET) {
3085 goto error;
3086 }
3087
3088 /*
3089 * For each consumer socket, create and send the relayd object of the
3090 * snapshot output.
3091 */
3092 rcu_read_lock();
3093 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
3094 socket, node.node) {
3095 ret = send_consumer_relayd_sockets(0, session->id,
3096 snap_output->consumer, socket,
3097 session->name, session->hostname,
3098 session->live_timer);
3099 if (ret != LTTNG_OK) {
3100 rcu_read_unlock();
3101 goto error;
3102 }
3103 }
3104 rcu_read_unlock();
3105
3106 error:
3107 return ret;
3108 }
3109
3110 /*
3111 * Record a kernel snapshot.
3112 *
3113 * Return LTTNG_OK on success or a LTTNG_ERR code.
3114 */
3115 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
3116 struct snapshot_output *output, struct ltt_session *session,
3117 int wait, uint64_t nb_packets_per_stream)
3118 {
3119 int ret;
3120
3121 assert(ksess);
3122 assert(output);
3123 assert(session);
3124
3125 /* Get the datetime for the snapshot output directory. */
3126 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
3127 sizeof(output->datetime));
3128 if (!ret) {
3129 ret = LTTNG_ERR_INVALID;
3130 goto error;
3131 }
3132
3133 /*
3134 * Copy kernel session sockets so we can communicate with the right
3135 * consumer for the snapshot record command.
3136 */
3137 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
3138 if (ret < 0) {
3139 ret = LTTNG_ERR_NOMEM;
3140 goto error;
3141 }
3142
3143 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
3144 if (ret != LTTNG_OK) {
3145 goto error_snapshot;
3146 }
3147
3148 ret = kernel_snapshot_record(ksess, output, wait, nb_packets_per_stream);
3149 if (ret != LTTNG_OK) {
3150 goto error_snapshot;
3151 }
3152
3153 ret = LTTNG_OK;
3154 goto end;
3155
3156 error_snapshot:
3157 /* Clean up copied sockets so this output can use some other later on. */
3158 consumer_destroy_output_sockets(output->consumer);
3159 error:
3160 end:
3161 return ret;
3162 }
3163
3164 /*
3165 * Record a UST snapshot.
3166 *
3167 * Return 0 on success or a LTTNG_ERR error code.
3168 */
3169 static int record_ust_snapshot(struct ltt_ust_session *usess,
3170 struct snapshot_output *output, struct ltt_session *session,
3171 int wait, uint64_t nb_packets_per_stream)
3172 {
3173 int ret;
3174
3175 assert(usess);
3176 assert(output);
3177 assert(session);
3178
3179 /* Get the datetime for the snapshot output directory. */
3180 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
3181 sizeof(output->datetime));
3182 if (!ret) {
3183 ret = LTTNG_ERR_INVALID;
3184 goto error;
3185 }
3186
3187 /*
3188 * Copy UST session sockets so we can communicate with the right
3189 * consumer for the snapshot record command.
3190 */
3191 ret = consumer_copy_sockets(output->consumer, usess->consumer);
3192 if (ret < 0) {
3193 ret = LTTNG_ERR_NOMEM;
3194 goto error;
3195 }
3196
3197 ret = set_relayd_for_snapshot(usess->consumer, output, session);
3198 if (ret != LTTNG_OK) {
3199 goto error_snapshot;
3200 }
3201
3202 ret = ust_app_snapshot_record(usess, output, wait, nb_packets_per_stream);
3203 if (ret < 0) {
3204 switch (-ret) {
3205 case EINVAL:
3206 ret = LTTNG_ERR_INVALID;
3207 break;
3208 case ENODATA:
3209 ret = LTTNG_ERR_SNAPSHOT_NODATA;
3210 break;
3211 default:
3212 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3213 break;
3214 }
3215 goto error_snapshot;
3216 }
3217
3218 ret = LTTNG_OK;
3219
3220 error_snapshot:
3221 /* Clean up copied sockets so this output can use some other later on. */
3222 consumer_destroy_output_sockets(output->consumer);
3223 error:
3224 return ret;
3225 }
3226
3227 static
3228 uint64_t get_session_size_one_more_packet_per_stream(struct ltt_session *session,
3229 uint64_t cur_nr_packets)
3230 {
3231 uint64_t tot_size = 0;
3232
3233 if (session->kernel_session) {
3234 struct ltt_kernel_channel *chan;
3235 struct ltt_kernel_session *ksess = session->kernel_session;
3236
3237 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
3238 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
3239 /*
3240 * Don't take channel into account if we
3241 * already grab all its packets.
3242 */
3243 continue;
3244 }
3245 tot_size += chan->channel->attr.subbuf_size
3246 * chan->stream_count;
3247 }
3248 }
3249
3250 if (session->ust_session) {
3251 struct ltt_ust_session *usess = session->ust_session;
3252
3253 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
3254 cur_nr_packets);
3255 }
3256
3257 return tot_size;
3258 }
3259
3260 /*
3261 * Calculate the number of packets we can grab from each stream that
3262 * fits within the overall snapshot max size.
3263 *
3264 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
3265 * the number of packets per stream.
3266 *
3267 * TODO: this approach is not perfect: we consider the worse case
3268 * (packet filling the sub-buffers) as an upper bound, but we could do
3269 * better if we do this calculation while we actually grab the packet
3270 * content: we would know how much padding we don't actually store into
3271 * the file.
3272 *
3273 * This algorithm is currently bounded by the number of packets per
3274 * stream.
3275 *
3276 * Since we call this algorithm before actually grabbing the data, it's
3277 * an approximation: for instance, applications could appear/disappear
3278 * in between this call and actually grabbing data.
3279 */
3280 static
3281 int64_t get_session_nb_packets_per_stream(struct ltt_session *session, uint64_t max_size)
3282 {
3283 int64_t size_left;
3284 uint64_t cur_nb_packets = 0;
3285
3286 if (!max_size) {
3287 return 0; /* Infinite */
3288 }
3289
3290 size_left = max_size;
3291 for (;;) {
3292 uint64_t one_more_packet_tot_size;
3293
3294 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(session,
3295 cur_nb_packets);
3296 if (!one_more_packet_tot_size) {
3297 /* We are already grabbing all packets. */
3298 break;
3299 }
3300 size_left -= one_more_packet_tot_size;
3301 if (size_left < 0) {
3302 break;
3303 }
3304 cur_nb_packets++;
3305 }
3306 if (!cur_nb_packets) {
3307 /* Not enough room to grab one packet of each stream, error. */
3308 return -1;
3309 }
3310 return cur_nb_packets;
3311 }
3312
3313 /*
3314 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
3315 *
3316 * The wait parameter is ignored so this call always wait for the snapshot to
3317 * complete before returning.
3318 *
3319 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3320 */
3321 int cmd_snapshot_record(struct ltt_session *session,
3322 struct lttng_snapshot_output *output, int wait)
3323 {
3324 int ret = LTTNG_OK;
3325 unsigned int use_tmp_output = 0;
3326 struct snapshot_output tmp_output;
3327 unsigned int snapshot_success = 0;
3328
3329 assert(session);
3330 assert(output);
3331
3332 DBG("Cmd snapshot record for session %s", session->name);
3333
3334 /*
3335 * Permission denied to create an output if the session is not
3336 * set in no output mode.
3337 */
3338 if (session->output_traces) {
3339 ret = LTTNG_ERR_EPERM;
3340 goto error;
3341 }
3342
3343 /* The session needs to be started at least once. */
3344 if (!session->has_been_started) {
3345 ret = LTTNG_ERR_START_SESSION_ONCE;
3346 goto error;
3347 }
3348
3349 /* Use temporary output for the session. */
3350 if (*output->ctrl_url != '\0') {
3351 ret = snapshot_output_init(output->max_size, output->name,
3352 output->ctrl_url, output->data_url, session->consumer,
3353 &tmp_output, NULL);
3354 if (ret < 0) {
3355 if (ret == -ENOMEM) {
3356 ret = LTTNG_ERR_NOMEM;
3357 } else {
3358 ret = LTTNG_ERR_INVALID;
3359 }
3360 goto error;
3361 }
3362 /* Use the global session count for the temporary snapshot. */
3363 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3364 use_tmp_output = 1;
3365 }
3366
3367 if (session->kernel_session) {
3368 struct ltt_kernel_session *ksess = session->kernel_session;
3369
3370 if (use_tmp_output) {
3371 int64_t nb_packets_per_stream;
3372
3373 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3374 tmp_output.max_size);
3375 if (nb_packets_per_stream < 0) {
3376 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3377 goto error;
3378 }
3379 ret = record_kernel_snapshot(ksess, &tmp_output, session,
3380 wait, nb_packets_per_stream);
3381 if (ret != LTTNG_OK) {
3382 goto error;
3383 }
3384 snapshot_success = 1;
3385 } else {
3386 struct snapshot_output *sout;
3387 struct lttng_ht_iter iter;
3388
3389 rcu_read_lock();
3390 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3391 &iter.iter, sout, node.node) {
3392 int64_t nb_packets_per_stream;
3393
3394 /*
3395 * Make a local copy of the output and assign the possible
3396 * temporary value given by the caller.
3397 */
3398 memset(&tmp_output, 0, sizeof(tmp_output));
3399 memcpy(&tmp_output, sout, sizeof(tmp_output));
3400
3401 if (output->max_size != (uint64_t) -1ULL) {
3402 tmp_output.max_size = output->max_size;
3403 }
3404
3405 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3406 tmp_output.max_size);
3407 if (nb_packets_per_stream < 0) {
3408 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3409 goto error;
3410 }
3411
3412 /* Use temporary name. */
3413 if (*output->name != '\0') {
3414 strncpy(tmp_output.name, output->name,
3415 sizeof(tmp_output.name));
3416 }
3417
3418 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3419
3420 ret = record_kernel_snapshot(ksess, &tmp_output,
3421 session, wait, nb_packets_per_stream);
3422 if (ret != LTTNG_OK) {
3423 rcu_read_unlock();
3424 goto error;
3425 }
3426 snapshot_success = 1;
3427 }
3428 rcu_read_unlock();
3429 }
3430 }
3431
3432 if (session->ust_session) {
3433 struct ltt_ust_session *usess = session->ust_session;
3434
3435 if (use_tmp_output) {
3436 int64_t nb_packets_per_stream;
3437
3438 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3439 tmp_output.max_size);
3440 if (nb_packets_per_stream < 0) {
3441 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3442 goto error;
3443 }
3444 ret = record_ust_snapshot(usess, &tmp_output, session,
3445 wait, nb_packets_per_stream);
3446 if (ret != LTTNG_OK) {
3447 goto error;
3448 }
3449 snapshot_success = 1;
3450 } else {
3451 struct snapshot_output *sout;
3452 struct lttng_ht_iter iter;
3453
3454 rcu_read_lock();
3455 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3456 &iter.iter, sout, node.node) {
3457 int64_t nb_packets_per_stream;
3458
3459 /*
3460 * Make a local copy of the output and assign the possible
3461 * temporary value given by the caller.
3462 */
3463 memset(&tmp_output, 0, sizeof(tmp_output));
3464 memcpy(&tmp_output, sout, sizeof(tmp_output));
3465
3466 if (output->max_size != (uint64_t) -1ULL) {
3467 tmp_output.max_size = output->max_size;
3468 }
3469
3470 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3471 tmp_output.max_size);
3472 if (nb_packets_per_stream < 0) {
3473 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3474 rcu_read_unlock();
3475 goto error;
3476 }
3477
3478 /* Use temporary name. */
3479 if (*output->name != '\0') {
3480 strncpy(tmp_output.name, output->name,
3481 sizeof(tmp_output.name));
3482 }
3483
3484 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3485
3486 ret = record_ust_snapshot(usess, &tmp_output, session,
3487 wait, nb_packets_per_stream);
3488 if (ret != LTTNG_OK) {
3489 rcu_read_unlock();
3490 goto error;
3491 }
3492 snapshot_success = 1;
3493 }
3494 rcu_read_unlock();
3495 }
3496 }
3497
3498 if (snapshot_success) {
3499 session->snapshot.nb_snapshot++;
3500 } else {
3501 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3502 }
3503
3504 error:
3505 return ret;
3506 }
3507
3508 /*
3509 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
3510 */
3511 int cmd_set_session_shm_path(struct ltt_session *session,
3512 const char *shm_path)
3513 {
3514 /* Safety net */
3515 assert(session);
3516
3517 /*
3518 * Can only set shm path before session is started.
3519 */
3520 if (session->has_been_started) {
3521 return LTTNG_ERR_SESSION_STARTED;
3522 }
3523
3524 strncpy(session->shm_path, shm_path,
3525 sizeof(session->shm_path));
3526 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
3527
3528 return 0;
3529 }
3530
3531 /*
3532 * Init command subsystem.
3533 */
3534 void cmd_init(void)
3535 {
3536 /*
3537 * Set network sequence index to 1 for streams to match a relayd
3538 * socket on the consumer side.
3539 */
3540 pthread_mutex_lock(&relayd_net_seq_idx_lock);
3541 relayd_net_seq_idx = 1;
3542 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
3543
3544 DBG("Command subsystem initialized");
3545 }
LTTng 2.0 tools and control repository
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