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Fix: reset consumer destination when changing URIs
[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 #include <assert.h>
20 #include <urcu/list.h>
21 #include <urcu/uatomic.h>
22
23 #include <common/defaults.h>
24 #include <common/common.h>
25 #include <common/sessiond-comm/sessiond-comm.h>
26 #include <common/relayd/relayd.h>
27
28 #include "channel.h"
29 #include "consumer.h"
30 #include "event.h"
31 #include "health.h"
32 #include "kernel.h"
33 #include "kernel-consumer.h"
34 #include "lttng-sessiond.h"
35 #include "utils.h"
36
37 #include "cmd.h"
38
39 /*
40 * Used to keep a unique index for each relayd socket created where this value
41 * is associated with streams on the consumer so it can match the right relayd
42 * to send to. It must be accessed with the relayd_net_seq_idx_lock
43 * held.
44 */
45 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
46 static uint64_t relayd_net_seq_idx;
47
48 /*
49 * Create a session path used by list_lttng_sessions for the case that the
50 * session consumer is on the network.
51 */
52 static int build_network_session_path(char *dst, size_t size,
53 struct ltt_session *session)
54 {
55 int ret, kdata_port, udata_port;
56 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
57 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
58
59 assert(session);
60 assert(dst);
61
62 memset(tmp_urls, 0, sizeof(tmp_urls));
63 memset(tmp_uurl, 0, sizeof(tmp_uurl));
64
65 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
66
67 if (session->kernel_session && session->kernel_session->consumer) {
68 kuri = &session->kernel_session->consumer->dst.net.control;
69 kdata_port = session->kernel_session->consumer->dst.net.data.port;
70 }
71
72 if (session->ust_session && session->ust_session->consumer) {
73 uuri = &session->ust_session->consumer->dst.net.control;
74 udata_port = session->ust_session->consumer->dst.net.data.port;
75 }
76
77 if (uuri == NULL && kuri == NULL) {
78 uri = &session->consumer->dst.net.control;
79 kdata_port = session->consumer->dst.net.data.port;
80 } else if (kuri && uuri) {
81 ret = uri_compare(kuri, uuri);
82 if (ret) {
83 /* Not Equal */
84 uri = kuri;
85 /* Build uuri URL string */
86 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
87 if (ret < 0) {
88 goto error;
89 }
90 } else {
91 uri = kuri;
92 }
93 } else if (kuri && uuri == NULL) {
94 uri = kuri;
95 } else if (uuri && kuri == NULL) {
96 uri = uuri;
97 }
98
99 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
100 if (ret < 0) {
101 goto error;
102 }
103
104 /*
105 * Do we have a UST url set. If yes, this means we have both kernel and UST
106 * to print.
107 */
108 if (*tmp_uurl != '\0') {
109 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
110 tmp_urls, kdata_port, tmp_uurl, udata_port);
111 } else {
112 int dport;
113 if (kuri) {
114 dport = kdata_port;
115 } else {
116 /* No kernel URI, use the UST port. */
117 dport = udata_port;
118 }
119 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
120 }
121
122 error:
123 return ret;
124 }
125
126 /*
127 * Fill lttng_channel array of all channels.
128 */
129 static void list_lttng_channels(int domain, struct ltt_session *session,
130 struct lttng_channel *channels)
131 {
132 int i = 0;
133 struct ltt_kernel_channel *kchan;
134
135 DBG("Listing channels for session %s", session->name);
136
137 switch (domain) {
138 case LTTNG_DOMAIN_KERNEL:
139 /* Kernel channels */
140 if (session->kernel_session != NULL) {
141 cds_list_for_each_entry(kchan,
142 &session->kernel_session->channel_list.head, list) {
143 /* Copy lttng_channel struct to array */
144 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
145 channels[i].enabled = kchan->enabled;
146 i++;
147 }
148 }
149 break;
150 case LTTNG_DOMAIN_UST:
151 {
152 struct lttng_ht_iter iter;
153 struct ltt_ust_channel *uchan;
154
155 rcu_read_lock();
156 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
157 &iter.iter, uchan, node.node) {
158 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
159 channels[i].attr.overwrite = uchan->attr.overwrite;
160 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
161 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
162 channels[i].attr.switch_timer_interval =
163 uchan->attr.switch_timer_interval;
164 channels[i].attr.read_timer_interval =
165 uchan->attr.read_timer_interval;
166 channels[i].enabled = uchan->enabled;
167 switch (uchan->attr.output) {
168 case LTTNG_UST_MMAP:
169 default:
170 channels[i].attr.output = LTTNG_EVENT_MMAP;
171 break;
172 }
173 i++;
174 }
175 rcu_read_unlock();
176 break;
177 }
178 default:
179 break;
180 }
181 }
182
183 /*
184 * Create a list of ust global domain events.
185 */
186 static int list_lttng_ust_global_events(char *channel_name,
187 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
188 {
189 int i = 0, ret = 0;
190 unsigned int nb_event = 0;
191 struct lttng_ht_iter iter;
192 struct lttng_ht_node_str *node;
193 struct ltt_ust_channel *uchan;
194 struct ltt_ust_event *uevent;
195 struct lttng_event *tmp;
196
197 DBG("Listing UST global events for channel %s", channel_name);
198
199 rcu_read_lock();
200
201 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
202 node = lttng_ht_iter_get_node_str(&iter);
203 if (node == NULL) {
204 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
205 goto error;
206 }
207
208 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
209
210 nb_event += lttng_ht_get_count(uchan->events);
211
212 if (nb_event == 0) {
213 ret = nb_event;
214 goto error;
215 }
216
217 DBG3("Listing UST global %d events", nb_event);
218
219 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
220 if (tmp == NULL) {
221 ret = LTTNG_ERR_FATAL;
222 goto error;
223 }
224
225 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
226 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
227 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
228 tmp[i].enabled = uevent->enabled;
229
230 switch (uevent->attr.instrumentation) {
231 case LTTNG_UST_TRACEPOINT:
232 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
233 break;
234 case LTTNG_UST_PROBE:
235 tmp[i].type = LTTNG_EVENT_PROBE;
236 break;
237 case LTTNG_UST_FUNCTION:
238 tmp[i].type = LTTNG_EVENT_FUNCTION;
239 break;
240 }
241
242 tmp[i].loglevel = uevent->attr.loglevel;
243 switch (uevent->attr.loglevel_type) {
244 case LTTNG_UST_LOGLEVEL_ALL:
245 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
246 break;
247 case LTTNG_UST_LOGLEVEL_RANGE:
248 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
249 break;
250 case LTTNG_UST_LOGLEVEL_SINGLE:
251 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
252 break;
253 }
254 if (uevent->filter) {
255 tmp[i].filter = 1;
256 }
257 i++;
258 }
259
260 ret = nb_event;
261 *events = tmp;
262
263 error:
264 rcu_read_unlock();
265 return ret;
266 }
267
268 /*
269 * Fill lttng_event array of all kernel events in the channel.
270 */
271 static int list_lttng_kernel_events(char *channel_name,
272 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
273 {
274 int i = 0, ret;
275 unsigned int nb_event;
276 struct ltt_kernel_event *event;
277 struct ltt_kernel_channel *kchan;
278
279 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
280 if (kchan == NULL) {
281 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
282 goto error;
283 }
284
285 nb_event = kchan->event_count;
286
287 DBG("Listing events for channel %s", kchan->channel->name);
288
289 if (nb_event == 0) {
290 goto end;
291 }
292
293 *events = zmalloc(nb_event * sizeof(struct lttng_event));
294 if (*events == NULL) {
295 ret = LTTNG_ERR_FATAL;
296 goto error;
297 }
298
299 /* Kernel channels */
300 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
301 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
302 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
303 (*events)[i].enabled = event->enabled;
304
305 switch (event->event->instrumentation) {
306 case LTTNG_KERNEL_TRACEPOINT:
307 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
308 break;
309 case LTTNG_KERNEL_KRETPROBE:
310 (*events)[i].type = LTTNG_EVENT_FUNCTION;
311 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
312 sizeof(struct lttng_kernel_kprobe));
313 break;
314 case LTTNG_KERNEL_KPROBE:
315 (*events)[i].type = LTTNG_EVENT_PROBE;
316 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
317 sizeof(struct lttng_kernel_kprobe));
318 break;
319 case LTTNG_KERNEL_FUNCTION:
320 (*events)[i].type = LTTNG_EVENT_FUNCTION;
321 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
322 sizeof(struct lttng_kernel_function));
323 break;
324 case LTTNG_KERNEL_NOOP:
325 (*events)[i].type = LTTNG_EVENT_NOOP;
326 break;
327 case LTTNG_KERNEL_SYSCALL:
328 (*events)[i].type = LTTNG_EVENT_SYSCALL;
329 break;
330 case LTTNG_KERNEL_ALL:
331 assert(0);
332 break;
333 }
334 i++;
335 }
336
337 end:
338 return nb_event;
339
340 error:
341 /* Negate the error code to differentiate the size from an error */
342 return -ret;
343 }
344
345 /*
346 * Add URI so the consumer output object. Set the correct path depending on the
347 * domain adding the default trace directory.
348 */
349 static int add_uri_to_consumer(struct consumer_output *consumer,
350 struct lttng_uri *uri, int domain, const char *session_name)
351 {
352 int ret = LTTNG_OK;
353 const char *default_trace_dir;
354
355 assert(uri);
356
357 if (consumer == NULL) {
358 DBG("No consumer detected. Don't add URI. Stopping.");
359 ret = LTTNG_ERR_NO_CONSUMER;
360 goto error;
361 }
362
363 switch (domain) {
364 case LTTNG_DOMAIN_KERNEL:
365 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
366 break;
367 case LTTNG_DOMAIN_UST:
368 default_trace_dir = DEFAULT_UST_TRACE_DIR;
369 break;
370 default:
371 /*
372 * This case is possible is we try to add the URI to the global tracing
373 * session consumer object which in this case there is no subdir.
374 */
375 default_trace_dir = "";
376 }
377
378 switch (uri->dtype) {
379 case LTTNG_DST_IPV4:
380 case LTTNG_DST_IPV6:
381 DBG2("Setting network URI to consumer");
382
383 if (consumer->type == CONSUMER_DST_NET) {
384 if ((uri->stype == LTTNG_STREAM_CONTROL &&
385 consumer->dst.net.control_isset) ||
386 (uri->stype == LTTNG_STREAM_DATA &&
387 consumer->dst.net.data_isset)) {
388 ret = LTTNG_ERR_URL_EXIST;
389 goto error;
390 }
391 } else {
392 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
393 }
394
395 consumer->type = CONSUMER_DST_NET;
396
397 /* Set URI into consumer output object */
398 ret = consumer_set_network_uri(consumer, uri);
399 if (ret < 0) {
400 ret = LTTNG_ERR_FATAL;
401 goto error;
402 } else if (ret == 1) {
403 /*
404 * URI was the same in the consumer so we do not append the subdir
405 * again so to not duplicate output dir.
406 */
407 goto error;
408 }
409
410 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
411 ret = consumer_set_subdir(consumer, session_name);
412 if (ret < 0) {
413 ret = LTTNG_ERR_FATAL;
414 goto error;
415 }
416 }
417
418 if (uri->stype == LTTNG_STREAM_CONTROL) {
419 /* On a new subdir, reappend the default trace dir. */
420 strncat(consumer->subdir, default_trace_dir,
421 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
422 DBG3("Append domain trace name to subdir %s", consumer->subdir);
423 }
424
425 break;
426 case LTTNG_DST_PATH:
427 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
428 memset(consumer->dst.trace_path, 0,
429 sizeof(consumer->dst.trace_path));
430 strncpy(consumer->dst.trace_path, uri->dst.path,
431 sizeof(consumer->dst.trace_path));
432 /* Append default trace dir */
433 strncat(consumer->dst.trace_path, default_trace_dir,
434 sizeof(consumer->dst.trace_path) -
435 strlen(consumer->dst.trace_path) - 1);
436 /* Flag consumer as local. */
437 consumer->type = CONSUMER_DST_LOCAL;
438 break;
439 }
440
441 error:
442 return ret;
443 }
444
445 /*
446 * Init tracing by creating trace directory and sending fds kernel consumer.
447 */
448 static int init_kernel_tracing(struct ltt_kernel_session *session)
449 {
450 int ret = 0;
451 struct lttng_ht_iter iter;
452 struct consumer_socket *socket;
453
454 assert(session);
455
456 rcu_read_lock();
457
458 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
459 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
460 socket, node.node) {
461 /* Code flow error */
462 assert(socket->fd >= 0);
463
464 pthread_mutex_lock(socket->lock);
465 ret = kernel_consumer_send_session(socket, session);
466 pthread_mutex_unlock(socket->lock);
467 if (ret < 0) {
468 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
469 goto error;
470 }
471 }
472 }
473
474 error:
475 rcu_read_unlock();
476 return ret;
477 }
478
479 /*
480 * Create a socket to the relayd using the URI.
481 *
482 * On success, the relayd_sock pointer is set to the created socket.
483 * Else, it's stays untouched and a lttcomm error code is returned.
484 */
485 static int create_connect_relayd(struct lttng_uri *uri,
486 struct lttcomm_relayd_sock **relayd_sock)
487 {
488 int ret;
489 struct lttcomm_relayd_sock *rsock;
490
491 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
492 RELAYD_VERSION_COMM_MINOR);
493 if (!rsock) {
494 ret = LTTNG_ERR_FATAL;
495 goto error;
496 }
497
498 /*
499 * Connect to relayd so we can proceed with a session creation. This call
500 * can possibly block for an arbitrary amount of time to set the health
501 * state to be in poll execution.
502 */
503 health_poll_entry();
504 ret = relayd_connect(rsock);
505 health_poll_exit();
506 if (ret < 0) {
507 ERR("Unable to reach lttng-relayd");
508 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
509 goto free_sock;
510 }
511
512 /* Create socket for control stream. */
513 if (uri->stype == LTTNG_STREAM_CONTROL) {
514 DBG3("Creating relayd stream socket from URI");
515
516 /* Check relayd version */
517 ret = relayd_version_check(rsock);
518 if (ret < 0) {
519 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
520 goto close_sock;
521 }
522 } else if (uri->stype == LTTNG_STREAM_DATA) {
523 DBG3("Creating relayd data socket from URI");
524 } else {
525 /* Command is not valid */
526 ERR("Relayd invalid stream type: %d", uri->stype);
527 ret = LTTNG_ERR_INVALID;
528 goto close_sock;
529 }
530
531 *relayd_sock = rsock;
532
533 return LTTNG_OK;
534
535 close_sock:
536 /* The returned value is not useful since we are on an error path. */
537 (void) relayd_close(rsock);
538 free_sock:
539 free(rsock);
540 error:
541 return ret;
542 }
543
544 /*
545 * Connect to the relayd using URI and send the socket to the right consumer.
546 */
547 static int send_consumer_relayd_socket(int domain, struct ltt_session *session,
548 struct lttng_uri *relayd_uri, struct consumer_output *consumer,
549 struct consumer_socket *consumer_sock)
550 {
551 int ret;
552 struct lttcomm_relayd_sock *rsock = NULL;
553
554 /* Connect to relayd and make version check if uri is the control. */
555 ret = create_connect_relayd(relayd_uri, &rsock);
556 if (ret != LTTNG_OK) {
557 goto error;
558 }
559 assert(rsock);
560
561 /* If the control socket is connected, network session is ready */
562 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
563 session->net_handle = 1;
564 }
565
566 /* Set the network sequence index if not set. */
567 if (consumer->net_seq_index == (uint64_t) -1ULL) {
568 pthread_mutex_lock(&relayd_net_seq_idx_lock);
569 /*
570 * Increment net_seq_idx because we are about to transfer the
571 * new relayd socket to the consumer.
572 * Assign unique key so the consumer can match streams.
573 */
574 consumer->net_seq_index = ++relayd_net_seq_idx;
575 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
576 }
577
578 /* Send relayd socket to consumer. */
579 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
580 relayd_uri->stype, session->id);
581 if (ret < 0) {
582 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
583 goto close_sock;
584 }
585
586 /* Flag that the corresponding socket was sent. */
587 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
588 consumer_sock->control_sock_sent = 1;
589 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
590 consumer_sock->data_sock_sent = 1;
591 }
592
593 ret = LTTNG_OK;
594
595 /*
596 * Close socket which was dup on the consumer side. The session daemon does
597 * NOT keep track of the relayd socket(s) once transfer to the consumer.
598 */
599
600 close_sock:
601 (void) relayd_close(rsock);
602 free(rsock);
603
604 error:
605 if (ret != LTTNG_OK) {
606 /*
607 * On error, nullify the consumer sequence index so streams are not
608 * associated with it once sent to the consumer.
609 */
610 uatomic_set(&consumer->net_seq_index, -1);
611 }
612 return ret;
613 }
614
615 /*
616 * Send both relayd sockets to a specific consumer and domain. This is a
617 * helper function to facilitate sending the information to the consumer for a
618 * session.
619 */
620 static int send_consumer_relayd_sockets(int domain,
621 struct ltt_session *session, struct consumer_output *consumer,
622 struct consumer_socket *sock)
623 {
624 int ret = LTTNG_OK;
625
626 assert(session);
627 assert(consumer);
628
629 /* Sending control relayd socket. */
630 if (!sock->control_sock_sent) {
631 ret = send_consumer_relayd_socket(domain, session,
632 &consumer->dst.net.control, consumer, sock);
633 if (ret != LTTNG_OK) {
634 goto error;
635 }
636 }
637
638 /* Sending data relayd socket. */
639 if (!sock->data_sock_sent) {
640 ret = send_consumer_relayd_socket(domain, session,
641 &consumer->dst.net.data, consumer, sock);
642 if (ret != LTTNG_OK) {
643 goto error;
644 }
645 }
646
647 error:
648 return ret;
649 }
650
651 /*
652 * Setup relayd connections for a tracing session. First creates the socket to
653 * the relayd and send them to the right domain consumer. Consumer type MUST be
654 * network.
655 */
656 int cmd_setup_relayd(struct ltt_session *session)
657 {
658 int ret = LTTNG_OK;
659 struct ltt_ust_session *usess;
660 struct ltt_kernel_session *ksess;
661 struct consumer_socket *socket;
662 struct lttng_ht_iter iter;
663
664 assert(session);
665
666 usess = session->ust_session;
667 ksess = session->kernel_session;
668
669 DBG("Setting relayd for session %s", session->name);
670
671 rcu_read_lock();
672
673 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
674 && usess->consumer->enabled) {
675 /* For each consumer socket, send relayd sockets */
676 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
677 socket, node.node) {
678 /* Code flow error */
679 assert(socket->fd >= 0);
680
681 pthread_mutex_lock(socket->lock);
682 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session,
683 usess->consumer, socket);
684 pthread_mutex_unlock(socket->lock);
685 if (ret != LTTNG_OK) {
686 goto error;
687 }
688 }
689 }
690
691 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
692 && ksess->consumer->enabled) {
693 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
694 socket, node.node) {
695 /* Code flow error */
696 assert(socket->fd >= 0);
697
698 pthread_mutex_lock(socket->lock);
699 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session,
700 ksess->consumer, socket);
701 pthread_mutex_unlock(socket->lock);
702 if (ret != LTTNG_OK) {
703 goto error;
704 }
705 }
706 }
707
708 error:
709 rcu_read_unlock();
710 return ret;
711 }
712
713 /*
714 * Start a kernel session by opening all necessary streams.
715 */
716 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
717 {
718 int ret;
719 struct ltt_kernel_channel *kchan;
720
721 /* Open kernel metadata */
722 if (ksess->metadata == NULL) {
723 ret = kernel_open_metadata(ksess);
724 if (ret < 0) {
725 ret = LTTNG_ERR_KERN_META_FAIL;
726 goto error;
727 }
728 }
729
730 /* Open kernel metadata stream */
731 if (ksess->metadata_stream_fd < 0) {
732 ret = kernel_open_metadata_stream(ksess);
733 if (ret < 0) {
734 ERR("Kernel create metadata stream failed");
735 ret = LTTNG_ERR_KERN_STREAM_FAIL;
736 goto error;
737 }
738 }
739
740 /* For each channel */
741 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
742 if (kchan->stream_count == 0) {
743 ret = kernel_open_channel_stream(kchan);
744 if (ret < 0) {
745 ret = LTTNG_ERR_KERN_STREAM_FAIL;
746 goto error;
747 }
748 /* Update the stream global counter */
749 ksess->stream_count_global += ret;
750 }
751 }
752
753 /* Setup kernel consumer socket and send fds to it */
754 ret = init_kernel_tracing(ksess);
755 if (ret < 0) {
756 ret = LTTNG_ERR_KERN_START_FAIL;
757 goto error;
758 }
759
760 /* This start the kernel tracing */
761 ret = kernel_start_session(ksess);
762 if (ret < 0) {
763 ret = LTTNG_ERR_KERN_START_FAIL;
764 goto error;
765 }
766
767 /* Quiescent wait after starting trace */
768 kernel_wait_quiescent(kernel_tracer_fd);
769
770 ksess->started = 1;
771
772 ret = LTTNG_OK;
773
774 error:
775 return ret;
776 }
777
778 /*
779 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
780 */
781 int cmd_disable_channel(struct ltt_session *session, int domain,
782 char *channel_name)
783 {
784 int ret;
785 struct ltt_ust_session *usess;
786
787 usess = session->ust_session;
788
789 rcu_read_lock();
790
791 switch (domain) {
792 case LTTNG_DOMAIN_KERNEL:
793 {
794 ret = channel_kernel_disable(session->kernel_session,
795 channel_name);
796 if (ret != LTTNG_OK) {
797 goto error;
798 }
799
800 kernel_wait_quiescent(kernel_tracer_fd);
801 break;
802 }
803 case LTTNG_DOMAIN_UST:
804 {
805 struct ltt_ust_channel *uchan;
806 struct lttng_ht *chan_ht;
807
808 chan_ht = usess->domain_global.channels;
809
810 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
811 if (uchan == NULL) {
812 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
813 goto error;
814 }
815
816 ret = channel_ust_disable(usess, uchan);
817 if (ret != LTTNG_OK) {
818 goto error;
819 }
820 break;
821 }
822 #if 0
823 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
824 case LTTNG_DOMAIN_UST_EXEC_NAME:
825 case LTTNG_DOMAIN_UST_PID:
826 #endif
827 default:
828 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
829 goto error;
830 }
831
832 ret = LTTNG_OK;
833
834 error:
835 rcu_read_unlock();
836 return ret;
837 }
838
839 /*
840 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
841 *
842 * The wpipe arguments is used as a notifier for the kernel thread.
843 */
844 int cmd_enable_channel(struct ltt_session *session,
845 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
846 {
847 int ret;
848 struct ltt_ust_session *usess = session->ust_session;
849 struct lttng_ht *chan_ht;
850
851 assert(session);
852 assert(attr);
853 assert(domain);
854
855 DBG("Enabling channel %s for session %s", attr->name, session->name);
856
857 rcu_read_lock();
858
859 switch (domain->type) {
860 case LTTNG_DOMAIN_KERNEL:
861 {
862 struct ltt_kernel_channel *kchan;
863
864 kchan = trace_kernel_get_channel_by_name(attr->name,
865 session->kernel_session);
866 if (kchan == NULL) {
867 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
868 } else {
869 ret = channel_kernel_enable(session->kernel_session, kchan);
870 }
871
872 if (ret != LTTNG_OK) {
873 goto error;
874 }
875
876 kernel_wait_quiescent(kernel_tracer_fd);
877
878 /*
879 * If the session was previously started, start as well this newly
880 * created kernel session so the events/channels enabled *after* the
881 * start actually work.
882 */
883 if (session->started && !session->kernel_session->started) {
884 ret = start_kernel_session(session->kernel_session, wpipe);
885 if (ret != LTTNG_OK) {
886 goto error;
887 }
888 }
889 break;
890 }
891 case LTTNG_DOMAIN_UST:
892 {
893 struct ltt_ust_channel *uchan;
894
895 chan_ht = usess->domain_global.channels;
896
897 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
898 if (uchan == NULL) {
899 ret = channel_ust_create(usess, attr, domain->buf_type);
900 } else {
901 ret = channel_ust_enable(usess, uchan);
902 }
903
904 /* Start the UST session if the session was already started. */
905 if (session->started && !usess->start_trace) {
906 ret = ust_app_start_trace_all(usess);
907 if (ret < 0) {
908 ret = LTTNG_ERR_UST_START_FAIL;
909 goto error;
910 }
911 ret = LTTNG_OK;
912 usess->start_trace = 1;
913 }
914 break;
915 }
916 default:
917 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
918 goto error;
919 }
920
921 error:
922 rcu_read_unlock();
923 return ret;
924 }
925
926
927 /*
928 * Command LTTNG_DISABLE_EVENT processed by the client thread.
929 */
930 int cmd_disable_event(struct ltt_session *session, int domain,
931 char *channel_name, char *event_name)
932 {
933 int ret;
934
935 rcu_read_lock();
936
937 switch (domain) {
938 case LTTNG_DOMAIN_KERNEL:
939 {
940 struct ltt_kernel_channel *kchan;
941 struct ltt_kernel_session *ksess;
942
943 ksess = session->kernel_session;
944
945 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
946 if (kchan == NULL) {
947 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
948 goto error;
949 }
950
951 ret = event_kernel_disable_tracepoint(kchan, event_name);
952 if (ret != LTTNG_OK) {
953 goto error;
954 }
955
956 kernel_wait_quiescent(kernel_tracer_fd);
957 break;
958 }
959 case LTTNG_DOMAIN_UST:
960 {
961 struct ltt_ust_channel *uchan;
962 struct ltt_ust_session *usess;
963
964 usess = session->ust_session;
965
966 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
967 channel_name);
968 if (uchan == NULL) {
969 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
970 goto error;
971 }
972
973 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
974 if (ret != LTTNG_OK) {
975 goto error;
976 }
977
978 DBG3("Disable UST event %s in channel %s completed", event_name,
979 channel_name);
980 break;
981 }
982 #if 0
983 case LTTNG_DOMAIN_UST_EXEC_NAME:
984 case LTTNG_DOMAIN_UST_PID:
985 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
986 #endif
987 default:
988 ret = LTTNG_ERR_UND;
989 goto error;
990 }
991
992 ret = LTTNG_OK;
993
994 error:
995 rcu_read_unlock();
996 return ret;
997 }
998
999 /*
1000 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
1001 */
1002 int cmd_disable_event_all(struct ltt_session *session, int domain,
1003 char *channel_name)
1004 {
1005 int ret;
1006
1007 rcu_read_lock();
1008
1009 switch (domain) {
1010 case LTTNG_DOMAIN_KERNEL:
1011 {
1012 struct ltt_kernel_session *ksess;
1013 struct ltt_kernel_channel *kchan;
1014
1015 ksess = session->kernel_session;
1016
1017 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1018 if (kchan == NULL) {
1019 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1020 goto error;
1021 }
1022
1023 ret = event_kernel_disable_all(kchan);
1024 if (ret != LTTNG_OK) {
1025 goto error;
1026 }
1027
1028 kernel_wait_quiescent(kernel_tracer_fd);
1029 break;
1030 }
1031 case LTTNG_DOMAIN_UST:
1032 {
1033 struct ltt_ust_session *usess;
1034 struct ltt_ust_channel *uchan;
1035
1036 usess = session->ust_session;
1037
1038 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1039 channel_name);
1040 if (uchan == NULL) {
1041 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1042 goto error;
1043 }
1044
1045 ret = event_ust_disable_all_tracepoints(usess, uchan);
1046 if (ret != 0) {
1047 goto error;
1048 }
1049
1050 DBG3("Disable all UST events in channel %s completed", channel_name);
1051
1052 break;
1053 }
1054 #if 0
1055 case LTTNG_DOMAIN_UST_EXEC_NAME:
1056 case LTTNG_DOMAIN_UST_PID:
1057 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1058 #endif
1059 default:
1060 ret = LTTNG_ERR_UND;
1061 goto error;
1062 }
1063
1064 ret = LTTNG_OK;
1065
1066 error:
1067 rcu_read_unlock();
1068 return ret;
1069 }
1070
1071 /*
1072 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1073 */
1074 int cmd_add_context(struct ltt_session *session, int domain,
1075 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1076 {
1077 int ret;
1078
1079 switch (domain) {
1080 case LTTNG_DOMAIN_KERNEL:
1081 assert(session->kernel_session);
1082
1083 if (session->kernel_session->channel_count == 0) {
1084 /* Create default channel */
1085 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1086 if (ret != LTTNG_OK) {
1087 goto error;
1088 }
1089 }
1090
1091 /* Add kernel context to kernel tracer */
1092 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1093 if (ret != LTTNG_OK) {
1094 goto error;
1095 }
1096 break;
1097 case LTTNG_DOMAIN_UST:
1098 {
1099 struct ltt_ust_session *usess = session->ust_session;
1100 assert(usess);
1101
1102 unsigned int chan_count =
1103 lttng_ht_get_count(usess->domain_global.channels);
1104 if (chan_count == 0) {
1105 struct lttng_channel *attr;
1106 /* Create default channel */
1107 attr = channel_new_default_attr(domain);
1108 if (attr == NULL) {
1109 ret = LTTNG_ERR_FATAL;
1110 goto error;
1111 }
1112
1113 ret = channel_ust_create(usess, attr, usess->buffer_type);
1114 if (ret != LTTNG_OK) {
1115 free(attr);
1116 goto error;
1117 }
1118 free(attr);
1119 }
1120
1121 ret = context_ust_add(usess, domain, ctx, channel_name);
1122 if (ret != LTTNG_OK) {
1123 goto error;
1124 }
1125 break;
1126 }
1127 #if 0
1128 case LTTNG_DOMAIN_UST_EXEC_NAME:
1129 case LTTNG_DOMAIN_UST_PID:
1130 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1131 #endif
1132 default:
1133 ret = LTTNG_ERR_UND;
1134 goto error;
1135 }
1136
1137 ret = LTTNG_OK;
1138
1139 error:
1140 return ret;
1141 }
1142
1143 /*
1144 * Command LTTNG_ENABLE_EVENT processed by the client thread.
1145 */
1146 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1147 char *channel_name, struct lttng_event *event,
1148 struct lttng_filter_bytecode *filter, int wpipe)
1149 {
1150 int ret, channel_created = 0;
1151 struct lttng_channel *attr;
1152
1153 assert(session);
1154 assert(event);
1155 assert(channel_name);
1156
1157 rcu_read_lock();
1158
1159 switch (domain->type) {
1160 case LTTNG_DOMAIN_KERNEL:
1161 {
1162 struct ltt_kernel_channel *kchan;
1163
1164 kchan = trace_kernel_get_channel_by_name(channel_name,
1165 session->kernel_session);
1166 if (kchan == NULL) {
1167 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL);
1168 if (attr == NULL) {
1169 ret = LTTNG_ERR_FATAL;
1170 goto error;
1171 }
1172 strncpy(attr->name, channel_name, sizeof(attr->name));
1173
1174 ret = cmd_enable_channel(session, domain, attr, wpipe);
1175 if (ret != LTTNG_OK) {
1176 free(attr);
1177 goto error;
1178 }
1179 free(attr);
1180
1181 channel_created = 1;
1182 }
1183
1184 /* Get the newly created kernel channel pointer */
1185 kchan = trace_kernel_get_channel_by_name(channel_name,
1186 session->kernel_session);
1187 if (kchan == NULL) {
1188 /* This sould not happen... */
1189 ret = LTTNG_ERR_FATAL;
1190 goto error;
1191 }
1192
1193 ret = event_kernel_enable_tracepoint(kchan, event);
1194 if (ret != LTTNG_OK) {
1195 if (channel_created) {
1196 /* Let's not leak a useless channel. */
1197 kernel_destroy_channel(kchan);
1198 }
1199 goto error;
1200 }
1201
1202 kernel_wait_quiescent(kernel_tracer_fd);
1203 break;
1204 }
1205 case LTTNG_DOMAIN_UST:
1206 {
1207 struct ltt_ust_channel *uchan;
1208 struct ltt_ust_session *usess = session->ust_session;
1209
1210 assert(usess);
1211
1212 /* Get channel from global UST domain */
1213 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1214 channel_name);
1215 if (uchan == NULL) {
1216 /* Create default channel */
1217 attr = channel_new_default_attr(LTTNG_DOMAIN_UST);
1218 if (attr == NULL) {
1219 ret = LTTNG_ERR_FATAL;
1220 goto error;
1221 }
1222 strncpy(attr->name, channel_name, sizeof(attr->name));
1223
1224 ret = cmd_enable_channel(session, domain, attr, wpipe);
1225 if (ret != LTTNG_OK) {
1226 free(attr);
1227 goto error;
1228 }
1229 free(attr);
1230
1231 /* Get the newly created channel reference back */
1232 uchan = trace_ust_find_channel_by_name(
1233 usess->domain_global.channels, channel_name);
1234 assert(uchan);
1235 }
1236
1237 /* At this point, the session and channel exist on the tracer */
1238 ret = event_ust_enable_tracepoint(usess, uchan, event, filter);
1239 if (ret != LTTNG_OK) {
1240 goto error;
1241 }
1242 break;
1243 }
1244 #if 0
1245 case LTTNG_DOMAIN_UST_EXEC_NAME:
1246 case LTTNG_DOMAIN_UST_PID:
1247 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1248 #endif
1249 default:
1250 ret = LTTNG_ERR_UND;
1251 goto error;
1252 }
1253
1254 ret = LTTNG_OK;
1255
1256 error:
1257 rcu_read_unlock();
1258 return ret;
1259 }
1260
1261 /*
1262 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
1263 */
1264 int cmd_enable_event_all(struct ltt_session *session,
1265 struct lttng_domain *domain, char *channel_name, int event_type,
1266 struct lttng_filter_bytecode *filter, int wpipe)
1267 {
1268 int ret;
1269 struct lttng_channel *attr;
1270
1271 assert(session);
1272 assert(channel_name);
1273
1274 rcu_read_lock();
1275
1276 switch (domain->type) {
1277 case LTTNG_DOMAIN_KERNEL:
1278 {
1279 struct ltt_kernel_channel *kchan;
1280
1281 assert(session->kernel_session);
1282
1283 kchan = trace_kernel_get_channel_by_name(channel_name,
1284 session->kernel_session);
1285 if (kchan == NULL) {
1286 /* Create default channel */
1287 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL);
1288 if (attr == NULL) {
1289 ret = LTTNG_ERR_FATAL;
1290 goto error;
1291 }
1292 strncpy(attr->name, channel_name, sizeof(attr->name));
1293
1294 ret = cmd_enable_channel(session, domain, attr, wpipe);
1295 if (ret != LTTNG_OK) {
1296 free(attr);
1297 goto error;
1298 }
1299 free(attr);
1300
1301 /* Get the newly created kernel channel pointer */
1302 kchan = trace_kernel_get_channel_by_name(channel_name,
1303 session->kernel_session);
1304 assert(kchan);
1305 }
1306
1307 switch (event_type) {
1308 case LTTNG_EVENT_SYSCALL:
1309 ret = event_kernel_enable_all_syscalls(kchan, kernel_tracer_fd);
1310 break;
1311 case LTTNG_EVENT_TRACEPOINT:
1312 /*
1313 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
1314 * events already registered to the channel.
1315 */
1316 ret = event_kernel_enable_all_tracepoints(kchan, kernel_tracer_fd);
1317 break;
1318 case LTTNG_EVENT_ALL:
1319 /* Enable syscalls and tracepoints */
1320 ret = event_kernel_enable_all(kchan, kernel_tracer_fd);
1321 break;
1322 default:
1323 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1324 goto error;
1325 }
1326
1327 /* Manage return value */
1328 if (ret != LTTNG_OK) {
1329 /*
1330 * On error, cmd_enable_channel call will take care of destroying
1331 * the created channel if it was needed.
1332 */
1333 goto error;
1334 }
1335
1336 kernel_wait_quiescent(kernel_tracer_fd);
1337 break;
1338 }
1339 case LTTNG_DOMAIN_UST:
1340 {
1341 struct ltt_ust_channel *uchan;
1342 struct ltt_ust_session *usess = session->ust_session;
1343
1344 assert(usess);
1345
1346 /* Get channel from global UST domain */
1347 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1348 channel_name);
1349 if (uchan == NULL) {
1350 /* Create default channel */
1351 attr = channel_new_default_attr(LTTNG_DOMAIN_UST);
1352 if (attr == NULL) {
1353 ret = LTTNG_ERR_FATAL;
1354 goto error;
1355 }
1356 strncpy(attr->name, channel_name, sizeof(attr->name));
1357
1358 ret = cmd_enable_channel(session, domain, attr, wpipe);
1359 if (ret != LTTNG_OK) {
1360 free(attr);
1361 goto error;
1362 }
1363 free(attr);
1364
1365 /* Get the newly created channel reference back */
1366 uchan = trace_ust_find_channel_by_name(
1367 usess->domain_global.channels, channel_name);
1368 assert(uchan);
1369 }
1370
1371 /* At this point, the session and channel exist on the tracer */
1372
1373 switch (event_type) {
1374 case LTTNG_EVENT_ALL:
1375 case LTTNG_EVENT_TRACEPOINT:
1376 ret = event_ust_enable_all_tracepoints(usess, uchan, filter);
1377 if (ret != LTTNG_OK) {
1378 goto error;
1379 }
1380 break;
1381 default:
1382 ret = LTTNG_ERR_UST_ENABLE_FAIL;
1383 goto error;
1384 }
1385
1386 /* Manage return value */
1387 if (ret != LTTNG_OK) {
1388 goto error;
1389 }
1390
1391 break;
1392 }
1393 #if 0
1394 case LTTNG_DOMAIN_UST_EXEC_NAME:
1395 case LTTNG_DOMAIN_UST_PID:
1396 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1397 #endif
1398 default:
1399 ret = LTTNG_ERR_UND;
1400 goto error;
1401 }
1402
1403 ret = LTTNG_OK;
1404
1405 error:
1406 rcu_read_unlock();
1407 return ret;
1408 }
1409
1410
1411 /*
1412 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1413 */
1414 ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
1415 {
1416 int ret;
1417 ssize_t nb_events = 0;
1418
1419 switch (domain) {
1420 case LTTNG_DOMAIN_KERNEL:
1421 nb_events = kernel_list_events(kernel_tracer_fd, events);
1422 if (nb_events < 0) {
1423 ret = LTTNG_ERR_KERN_LIST_FAIL;
1424 goto error;
1425 }
1426 break;
1427 case LTTNG_DOMAIN_UST:
1428 nb_events = ust_app_list_events(events);
1429 if (nb_events < 0) {
1430 ret = LTTNG_ERR_UST_LIST_FAIL;
1431 goto error;
1432 }
1433 break;
1434 default:
1435 ret = LTTNG_ERR_UND;
1436 goto error;
1437 }
1438
1439 return nb_events;
1440
1441 error:
1442 /* Return negative value to differentiate return code */
1443 return -ret;
1444 }
1445
1446 /*
1447 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1448 */
1449 ssize_t cmd_list_tracepoint_fields(int domain,
1450 struct lttng_event_field **fields)
1451 {
1452 int ret;
1453 ssize_t nb_fields = 0;
1454
1455 switch (domain) {
1456 case LTTNG_DOMAIN_UST:
1457 nb_fields = ust_app_list_event_fields(fields);
1458 if (nb_fields < 0) {
1459 ret = LTTNG_ERR_UST_LIST_FAIL;
1460 goto error;
1461 }
1462 break;
1463 case LTTNG_DOMAIN_KERNEL:
1464 default: /* fall-through */
1465 ret = LTTNG_ERR_UND;
1466 goto error;
1467 }
1468
1469 return nb_fields;
1470
1471 error:
1472 /* Return negative value to differentiate return code */
1473 return -ret;
1474 }
1475
1476 /*
1477 * Command LTTNG_START_TRACE processed by the client thread.
1478 */
1479 int cmd_start_trace(struct ltt_session *session)
1480 {
1481 int ret;
1482 struct ltt_kernel_session *ksession;
1483 struct ltt_ust_session *usess;
1484
1485 assert(session);
1486
1487 /* Ease our life a bit ;) */
1488 ksession = session->kernel_session;
1489 usess = session->ust_session;
1490
1491 if (session->enabled) {
1492 /* Already started. */
1493 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1494 goto error;
1495 }
1496
1497 session->enabled = 1;
1498
1499 /* Kernel tracing */
1500 if (ksession != NULL) {
1501 ret = start_kernel_session(ksession, kernel_tracer_fd);
1502 if (ret != LTTNG_OK) {
1503 goto error;
1504 }
1505 }
1506
1507 /* Flag session that trace should start automatically */
1508 if (usess) {
1509 usess->start_trace = 1;
1510
1511 ret = ust_app_start_trace_all(usess);
1512 if (ret < 0) {
1513 ret = LTTNG_ERR_UST_START_FAIL;
1514 goto error;
1515 }
1516 }
1517
1518 session->started = 1;
1519
1520 ret = LTTNG_OK;
1521
1522 error:
1523 return ret;
1524 }
1525
1526 /*
1527 * Command LTTNG_STOP_TRACE processed by the client thread.
1528 */
1529 int cmd_stop_trace(struct ltt_session *session)
1530 {
1531 int ret;
1532 struct ltt_kernel_channel *kchan;
1533 struct ltt_kernel_session *ksession;
1534 struct ltt_ust_session *usess;
1535
1536 assert(session);
1537
1538 /* Short cut */
1539 ksession = session->kernel_session;
1540 usess = session->ust_session;
1541
1542 if (!session->enabled) {
1543 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
1544 goto error;
1545 }
1546
1547 session->enabled = 0;
1548
1549 /* Kernel tracer */
1550 if (ksession) {
1551 DBG("Stop kernel tracing");
1552
1553 /* Flush metadata if exist */
1554 if (ksession->metadata_stream_fd >= 0) {
1555 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
1556 if (ret < 0) {
1557 ERR("Kernel metadata flush failed");
1558 }
1559 }
1560
1561 /* Flush all buffers before stopping */
1562 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
1563 ret = kernel_flush_buffer(kchan);
1564 if (ret < 0) {
1565 ERR("Kernel flush buffer error");
1566 }
1567 }
1568
1569 ret = kernel_stop_session(ksession);
1570 if (ret < 0) {
1571 ret = LTTNG_ERR_KERN_STOP_FAIL;
1572 goto error;
1573 }
1574
1575 kernel_wait_quiescent(kernel_tracer_fd);
1576
1577 ksession->started = 0;
1578 }
1579
1580 if (usess) {
1581 usess->start_trace = 0;
1582
1583 ret = ust_app_stop_trace_all(usess);
1584 if (ret < 0) {
1585 ret = LTTNG_ERR_UST_STOP_FAIL;
1586 goto error;
1587 }
1588 }
1589
1590 session->started = 0;
1591
1592 ret = LTTNG_OK;
1593
1594 error:
1595 return ret;
1596 }
1597
1598 /*
1599 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
1600 */
1601 int cmd_set_consumer_uri(int domain, struct ltt_session *session,
1602 size_t nb_uri, struct lttng_uri *uris)
1603 {
1604 int ret, i;
1605 struct ltt_kernel_session *ksess = session->kernel_session;
1606 struct ltt_ust_session *usess = session->ust_session;
1607 struct consumer_output *consumer = NULL;
1608
1609 assert(session);
1610 assert(uris);
1611 assert(nb_uri > 0);
1612
1613 /* Can't enable consumer after session started. */
1614 if (session->enabled) {
1615 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1616 goto error;
1617 }
1618
1619 /*
1620 * This case switch makes sure the domain session has a temporary consumer
1621 * so the URL can be set.
1622 */
1623 switch (domain) {
1624 case 0:
1625 /* Code flow error. A session MUST always have a consumer object */
1626 assert(session->consumer);
1627 /*
1628 * The URL will be added to the tracing session consumer instead of a
1629 * specific domain consumer.
1630 */
1631 consumer = session->consumer;
1632 break;
1633 case LTTNG_DOMAIN_KERNEL:
1634 /* Code flow error if we don't have a kernel session here. */
1635 assert(ksess);
1636 assert(ksess->consumer);
1637 consumer = ksess->consumer;
1638 break;
1639 case LTTNG_DOMAIN_UST:
1640 /* Code flow error if we don't have a kernel session here. */
1641 assert(usess);
1642 assert(usess->consumer);
1643 consumer = usess->consumer;
1644 break;
1645 }
1646
1647 for (i = 0; i < nb_uri; i++) {
1648 ret = add_uri_to_consumer(consumer, &uris[i], domain, session->name);
1649 if (ret < 0) {
1650 goto error;
1651 }
1652 }
1653
1654 /* All good! */
1655 ret = LTTNG_OK;
1656
1657 error:
1658 return ret;
1659 }
1660
1661 /*
1662 * Command LTTNG_CREATE_SESSION processed by the client thread.
1663 */
1664 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
1665 size_t nb_uri, lttng_sock_cred *creds)
1666 {
1667 int ret;
1668 char *path = NULL;
1669 struct ltt_session *session;
1670
1671 assert(name);
1672
1673 /* No URIs is not possible. */
1674 if (uris == NULL) {
1675 ret = LTTNG_ERR_SESSION_FAIL;
1676 goto session_error;
1677 }
1678
1679 /*
1680 * Verify if the session already exist
1681 *
1682 * XXX: There is no need for the session lock list here since the caller
1683 * (process_client_msg) is holding it. We might want to change that so a
1684 * single command does not lock the entire session list.
1685 */
1686 session = session_find_by_name(name);
1687 if (session != NULL) {
1688 ret = LTTNG_ERR_EXIST_SESS;
1689 goto find_error;
1690 }
1691
1692 /* Create tracing session in the registry */
1693 ret = session_create(name, path, LTTNG_SOCK_GET_UID_CRED(creds),
1694 LTTNG_SOCK_GET_GID_CRED(creds));
1695 if (ret != LTTNG_OK) {
1696 goto session_error;
1697 }
1698
1699 /*
1700 * Get the newly created session pointer back
1701 *
1702 * XXX: There is no need for the session lock list here since the caller
1703 * (process_client_msg) is holding it. We might want to change that so a
1704 * single command does not lock the entire session list.
1705 */
1706 session = session_find_by_name(name);
1707 assert(session);
1708
1709 /* Create default consumer output for the session not yet created. */
1710 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
1711 if (session->consumer == NULL) {
1712 ret = LTTNG_ERR_FATAL;
1713 goto consumer_error;
1714 }
1715
1716 ret = cmd_set_consumer_uri(0, session, nb_uri, uris);
1717 if (ret != LTTNG_OK) {
1718 goto consumer_error;
1719 }
1720
1721 session->consumer->enabled = 1;
1722
1723 return LTTNG_OK;
1724
1725 consumer_error:
1726 session_destroy(session);
1727 session_error:
1728 find_error:
1729 return ret;
1730 }
1731
1732 /*
1733 * Command LTTNG_DESTROY_SESSION processed by the client thread.
1734 */
1735 int cmd_destroy_session(struct ltt_session *session, int wpipe)
1736 {
1737 int ret;
1738 struct ltt_ust_session *usess;
1739 struct ltt_kernel_session *ksess;
1740
1741 /* Safety net */
1742 assert(session);
1743
1744 usess = session->ust_session;
1745 ksess = session->kernel_session;
1746
1747 /* Clean kernel session teardown */
1748 kernel_destroy_session(ksess);
1749
1750 /* UST session teardown */
1751 if (usess) {
1752 /* Close any relayd session */
1753 consumer_output_send_destroy_relayd(usess->consumer);
1754
1755 /* Destroy every UST application related to this session. */
1756 ret = ust_app_destroy_trace_all(usess);
1757 if (ret) {
1758 ERR("Error in ust_app_destroy_trace_all");
1759 }
1760
1761 /* Clean up the rest. */
1762 trace_ust_destroy_session(usess);
1763 }
1764
1765 /*
1766 * Must notify the kernel thread here to update it's poll set in order to
1767 * remove the channel(s)' fd just destroyed.
1768 */
1769 ret = notify_thread_pipe(wpipe);
1770 if (ret < 0) {
1771 PERROR("write kernel poll pipe");
1772 }
1773
1774 ret = session_destroy(session);
1775
1776 return ret;
1777 }
1778
1779 /*
1780 * Command LTTNG_CALIBRATE processed by the client thread.
1781 */
1782 int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
1783 {
1784 int ret;
1785
1786 switch (domain) {
1787 case LTTNG_DOMAIN_KERNEL:
1788 {
1789 struct lttng_kernel_calibrate kcalibrate;
1790
1791 kcalibrate.type = calibrate->type;
1792 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
1793 if (ret < 0) {
1794 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1795 goto error;
1796 }
1797 break;
1798 }
1799 case LTTNG_DOMAIN_UST:
1800 {
1801 struct lttng_ust_calibrate ucalibrate;
1802
1803 ucalibrate.type = calibrate->type;
1804 ret = ust_app_calibrate_glb(&ucalibrate);
1805 if (ret < 0) {
1806 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
1807 goto error;
1808 }
1809 break;
1810 }
1811 default:
1812 ret = LTTNG_ERR_UND;
1813 goto error;
1814 }
1815
1816 ret = LTTNG_OK;
1817
1818 error:
1819 return ret;
1820 }
1821
1822 /*
1823 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
1824 */
1825 int cmd_register_consumer(struct ltt_session *session, int domain,
1826 const char *sock_path, struct consumer_data *cdata)
1827 {
1828 int ret, sock;
1829 struct consumer_socket *socket;
1830
1831 assert(session);
1832 assert(cdata);
1833 assert(sock_path);
1834
1835 switch (domain) {
1836 case LTTNG_DOMAIN_KERNEL:
1837 {
1838 struct ltt_kernel_session *ksess = session->kernel_session;
1839
1840 assert(ksess);
1841
1842 /* Can't register a consumer if there is already one */
1843 if (ksess->consumer_fds_sent != 0) {
1844 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
1845 goto error;
1846 }
1847
1848 sock = lttcomm_connect_unix_sock(sock_path);
1849 if (sock < 0) {
1850 ret = LTTNG_ERR_CONNECT_FAIL;
1851 goto error;
1852 }
1853
1854 socket = consumer_allocate_socket(sock);
1855 if (socket == NULL) {
1856 ret = close(sock);
1857 if (ret < 0) {
1858 PERROR("close register consumer");
1859 }
1860 ret = LTTNG_ERR_FATAL;
1861 goto error;
1862 }
1863
1864 socket->lock = zmalloc(sizeof(pthread_mutex_t));
1865 if (socket->lock == NULL) {
1866 PERROR("zmalloc pthread mutex");
1867 ret = LTTNG_ERR_FATAL;
1868 goto error;
1869 }
1870 pthread_mutex_init(socket->lock, NULL);
1871 socket->registered = 1;
1872
1873 rcu_read_lock();
1874 consumer_add_socket(socket, ksess->consumer);
1875 rcu_read_unlock();
1876
1877 pthread_mutex_lock(&cdata->pid_mutex);
1878 cdata->pid = -1;
1879 pthread_mutex_unlock(&cdata->pid_mutex);
1880
1881 break;
1882 }
1883 default:
1884 /* TODO: Userspace tracing */
1885 ret = LTTNG_ERR_UND;
1886 goto error;
1887 }
1888
1889 ret = LTTNG_OK;
1890
1891 error:
1892 return ret;
1893 }
1894
1895 /*
1896 * Command LTTNG_LIST_DOMAINS processed by the client thread.
1897 */
1898 ssize_t cmd_list_domains(struct ltt_session *session,
1899 struct lttng_domain **domains)
1900 {
1901 int ret, index = 0;
1902 ssize_t nb_dom = 0;
1903
1904 if (session->kernel_session != NULL) {
1905 DBG3("Listing domains found kernel domain");
1906 nb_dom++;
1907 }
1908
1909 if (session->ust_session != NULL) {
1910 DBG3("Listing domains found UST global domain");
1911 nb_dom++;
1912 }
1913
1914 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
1915 if (*domains == NULL) {
1916 ret = LTTNG_ERR_FATAL;
1917 goto error;
1918 }
1919
1920 if (session->kernel_session != NULL) {
1921 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
1922 index++;
1923 }
1924
1925 if (session->ust_session != NULL) {
1926 (*domains)[index].type = LTTNG_DOMAIN_UST;
1927 (*domains)[index].buf_type = session->ust_session->buffer_type;
1928 index++;
1929 }
1930
1931 return nb_dom;
1932
1933 error:
1934 /* Return negative value to differentiate return code */
1935 return -ret;
1936 }
1937
1938
1939 /*
1940 * Command LTTNG_LIST_CHANNELS processed by the client thread.
1941 */
1942 ssize_t cmd_list_channels(int domain, struct ltt_session *session,
1943 struct lttng_channel **channels)
1944 {
1945 int ret;
1946 ssize_t nb_chan = 0;
1947
1948 switch (domain) {
1949 case LTTNG_DOMAIN_KERNEL:
1950 if (session->kernel_session != NULL) {
1951 nb_chan = session->kernel_session->channel_count;
1952 }
1953 DBG3("Number of kernel channels %zd", nb_chan);
1954 if (nb_chan <= 0) {
1955 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1956 }
1957 break;
1958 case LTTNG_DOMAIN_UST:
1959 if (session->ust_session != NULL) {
1960 nb_chan = lttng_ht_get_count(
1961 session->ust_session->domain_global.channels);
1962 }
1963 DBG3("Number of UST global channels %zd", nb_chan);
1964 if (nb_chan <= 0) {
1965 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1966 }
1967 break;
1968 default:
1969 *channels = NULL;
1970 ret = LTTNG_ERR_UND;
1971 goto error;
1972 }
1973
1974 if (nb_chan > 0) {
1975 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
1976 if (*channels == NULL) {
1977 ret = LTTNG_ERR_FATAL;
1978 goto error;
1979 }
1980
1981 list_lttng_channels(domain, session, *channels);
1982 } else {
1983 *channels = NULL;
1984 /* Ret value was set in the domain switch case */
1985 goto error;
1986 }
1987
1988 return nb_chan;
1989
1990 error:
1991 /* Return negative value to differentiate return code */
1992 return -ret;
1993 }
1994
1995 /*
1996 * Command LTTNG_LIST_EVENTS processed by the client thread.
1997 */
1998 ssize_t cmd_list_events(int domain, struct ltt_session *session,
1999 char *channel_name, struct lttng_event **events)
2000 {
2001 int ret = 0;
2002 ssize_t nb_event = 0;
2003
2004 switch (domain) {
2005 case LTTNG_DOMAIN_KERNEL:
2006 if (session->kernel_session != NULL) {
2007 nb_event = list_lttng_kernel_events(channel_name,
2008 session->kernel_session, events);
2009 }
2010 break;
2011 case LTTNG_DOMAIN_UST:
2012 {
2013 if (session->ust_session != NULL) {
2014 nb_event = list_lttng_ust_global_events(channel_name,
2015 &session->ust_session->domain_global, events);
2016 }
2017 break;
2018 }
2019 default:
2020 ret = LTTNG_ERR_UND;
2021 goto error;
2022 }
2023
2024 return nb_event;
2025
2026 error:
2027 /* Return negative value to differentiate return code */
2028 return -ret;
2029 }
2030
2031 /*
2032 * Using the session list, filled a lttng_session array to send back to the
2033 * client for session listing.
2034 *
2035 * The session list lock MUST be acquired before calling this function. Use
2036 * session_lock_list() and session_unlock_list().
2037 */
2038 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2039 gid_t gid)
2040 {
2041 int ret;
2042 unsigned int i = 0;
2043 struct ltt_session *session;
2044 struct ltt_session_list *list = session_get_list();
2045
2046 DBG("Getting all available session for UID %d GID %d",
2047 uid, gid);
2048 /*
2049 * Iterate over session list and append data after the control struct in
2050 * the buffer.
2051 */
2052 cds_list_for_each_entry(session, &list->head, list) {
2053 /*
2054 * Only list the sessions the user can control.
2055 */
2056 if (!session_access_ok(session, uid, gid)) {
2057 continue;
2058 }
2059
2060 struct ltt_kernel_session *ksess = session->kernel_session;
2061 struct ltt_ust_session *usess = session->ust_session;
2062
2063 if (session->consumer->type == CONSUMER_DST_NET ||
2064 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2065 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2066 ret = build_network_session_path(sessions[i].path,
2067 sizeof(session[i].path), session);
2068 } else {
2069 ret = snprintf(sessions[i].path, sizeof(session[i].path), "%s",
2070 session->consumer->dst.trace_path);
2071 }
2072 if (ret < 0) {
2073 PERROR("snprintf session path");
2074 continue;
2075 }
2076
2077 strncpy(sessions[i].name, session->name, NAME_MAX);
2078 sessions[i].name[NAME_MAX - 1] = '\0';
2079 sessions[i].enabled = session->enabled;
2080 i++;
2081 }
2082 }
2083
2084 /*
2085 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2086 * ready for trace analysis (or anykind of reader) or else 1 for pending data.
2087 */
2088 int cmd_data_pending(struct ltt_session *session)
2089 {
2090 int ret;
2091 struct ltt_kernel_session *ksess = session->kernel_session;
2092 struct ltt_ust_session *usess = session->ust_session;
2093
2094 assert(session);
2095
2096 /* Session MUST be stopped to ask for data availability. */
2097 if (session->enabled) {
2098 ret = LTTNG_ERR_SESSION_STARTED;
2099 goto error;
2100 }
2101
2102 if (ksess && ksess->consumer) {
2103 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2104 if (ret == 1) {
2105 /* Data is still being extracted for the kernel. */
2106 goto error;
2107 }
2108 }
2109
2110 if (usess && usess->consumer) {
2111 ret = consumer_is_data_pending(usess->id, usess->consumer);
2112 if (ret == 1) {
2113 /* Data is still being extracted for the kernel. */
2114 goto error;
2115 }
2116 }
2117
2118 /* Data is ready to be read by a viewer */
2119 ret = 0;
2120
2121 error:
2122 return ret;
2123 }
2124
2125 /*
2126 * Init command subsystem.
2127 */
2128 void cmd_init(void)
2129 {
2130 /*
2131 * Set network sequence index to 1 for streams to match a relayd
2132 * socket on the consumer side.
2133 */
2134 pthread_mutex_lock(&relayd_net_seq_idx_lock);
2135 relayd_net_seq_idx = 1;
2136 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
2137
2138 DBG("Command subsystem initialized");
2139 }
LTTng 2.0 tools and control repository
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