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