bcf349f9290476de0268dce0e9a535e331d6dedc
[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 || (!kuri && !uuri)) {
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 = -ret;
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 ret = LTTNG_OK;
442
443 error:
444 return ret;
445 }
446
447 /*
448 * Init tracing by creating trace directory and sending fds kernel consumer.
449 */
450 static int init_kernel_tracing(struct ltt_kernel_session *session)
451 {
452 int ret = 0;
453 struct lttng_ht_iter iter;
454 struct consumer_socket *socket;
455
456 assert(session);
457
458 rcu_read_lock();
459
460 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
461 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
462 socket, node.node) {
463 /* Code flow error */
464 assert(socket->fd >= 0);
465
466 pthread_mutex_lock(socket->lock);
467 ret = kernel_consumer_send_session(socket, session);
468 pthread_mutex_unlock(socket->lock);
469 if (ret < 0) {
470 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
471 goto error;
472 }
473 }
474 }
475
476 error:
477 rcu_read_unlock();
478 return ret;
479 }
480
481 /*
482 * Create a socket to the relayd using the URI.
483 *
484 * On success, the relayd_sock pointer is set to the created socket.
485 * Else, it's stays untouched and a lttcomm error code is returned.
486 */
487 static int create_connect_relayd(struct lttng_uri *uri,
488 struct lttcomm_relayd_sock **relayd_sock)
489 {
490 int ret;
491 struct lttcomm_relayd_sock *rsock;
492
493 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
494 RELAYD_VERSION_COMM_MINOR);
495 if (!rsock) {
496 ret = LTTNG_ERR_FATAL;
497 goto error;
498 }
499
500 /*
501 * Connect to relayd so we can proceed with a session creation. This call
502 * can possibly block for an arbitrary amount of time to set the health
503 * state to be in poll execution.
504 */
505 health_poll_entry();
506 ret = relayd_connect(rsock);
507 health_poll_exit();
508 if (ret < 0) {
509 ERR("Unable to reach lttng-relayd");
510 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
511 goto free_sock;
512 }
513
514 /* Create socket for control stream. */
515 if (uri->stype == LTTNG_STREAM_CONTROL) {
516 DBG3("Creating relayd stream socket from URI");
517
518 /* Check relayd version */
519 ret = relayd_version_check(rsock);
520 if (ret < 0) {
521 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
522 goto close_sock;
523 }
524 } else if (uri->stype == LTTNG_STREAM_DATA) {
525 DBG3("Creating relayd data socket from URI");
526 } else {
527 /* Command is not valid */
528 ERR("Relayd invalid stream type: %d", uri->stype);
529 ret = LTTNG_ERR_INVALID;
530 goto close_sock;
531 }
532
533 *relayd_sock = rsock;
534
535 return LTTNG_OK;
536
537 close_sock:
538 /* The returned value is not useful since we are on an error path. */
539 (void) relayd_close(rsock);
540 free_sock:
541 free(rsock);
542 error:
543 return ret;
544 }
545
546 /*
547 * Connect to the relayd using URI and send the socket to the right consumer.
548 */
549 static int send_consumer_relayd_socket(int domain, struct ltt_session *session,
550 struct lttng_uri *relayd_uri, struct consumer_output *consumer,
551 struct consumer_socket *consumer_sock)
552 {
553 int ret;
554 struct lttcomm_relayd_sock *rsock = NULL;
555
556 /* Connect to relayd and make version check if uri is the control. */
557 ret = create_connect_relayd(relayd_uri, &rsock);
558 if (ret != LTTNG_OK) {
559 goto error;
560 }
561 assert(rsock);
562
563 /* If the control socket is connected, network session is ready */
564 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
565 session->net_handle = 1;
566 }
567
568 /* Set the network sequence index if not set. */
569 if (consumer->net_seq_index == (uint64_t) -1ULL) {
570 pthread_mutex_lock(&relayd_net_seq_idx_lock);
571 /*
572 * Increment net_seq_idx because we are about to transfer the
573 * new relayd socket to the consumer.
574 * Assign unique key so the consumer can match streams.
575 */
576 consumer->net_seq_index = ++relayd_net_seq_idx;
577 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
578 }
579
580 /* Send relayd socket to consumer. */
581 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
582 relayd_uri->stype, session->id);
583 if (ret < 0) {
584 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
585 goto close_sock;
586 }
587
588 /* Flag that the corresponding socket was sent. */
589 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
590 consumer_sock->control_sock_sent = 1;
591 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
592 consumer_sock->data_sock_sent = 1;
593 }
594
595 ret = LTTNG_OK;
596
597 /*
598 * Close socket which was dup on the consumer side. The session daemon does
599 * NOT keep track of the relayd socket(s) once transfer to the consumer.
600 */
601
602 close_sock:
603 (void) relayd_close(rsock);
604 free(rsock);
605
606 error:
607 if (ret != LTTNG_OK) {
608 /*
609 * The consumer output for this session should not be used anymore
610 * since the relayd connection failed thus making any tracing or/and
611 * streaming not usable.
612 */
613 consumer->enabled = 0;
614 }
615 return ret;
616 }
617
618 /*
619 * Send both relayd sockets to a specific consumer and domain. This is a
620 * helper function to facilitate sending the information to the consumer for a
621 * session.
622 */
623 static int send_consumer_relayd_sockets(int domain,
624 struct ltt_session *session, struct consumer_output *consumer,
625 struct consumer_socket *sock)
626 {
627 int ret = LTTNG_OK;
628
629 assert(session);
630 assert(consumer);
631
632 /* Sending control relayd socket. */
633 if (!sock->control_sock_sent) {
634 ret = send_consumer_relayd_socket(domain, session,
635 &consumer->dst.net.control, consumer, sock);
636 if (ret != LTTNG_OK) {
637 goto error;
638 }
639 }
640
641 /* Sending data relayd socket. */
642 if (!sock->data_sock_sent) {
643 ret = send_consumer_relayd_socket(domain, session,
644 &consumer->dst.net.data, consumer, sock);
645 if (ret != LTTNG_OK) {
646 goto error;
647 }
648 }
649
650 error:
651 return ret;
652 }
653
654 /*
655 * Setup relayd connections for a tracing session. First creates the socket to
656 * the relayd and send them to the right domain consumer. Consumer type MUST be
657 * network.
658 */
659 int cmd_setup_relayd(struct ltt_session *session)
660 {
661 int ret = LTTNG_OK;
662 struct ltt_ust_session *usess;
663 struct ltt_kernel_session *ksess;
664 struct consumer_socket *socket;
665 struct lttng_ht_iter iter;
666
667 assert(session);
668
669 usess = session->ust_session;
670 ksess = session->kernel_session;
671
672 DBG("Setting relayd for session %s", session->name);
673
674 rcu_read_lock();
675
676 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
677 && usess->consumer->enabled) {
678 /* For each consumer socket, send relayd sockets */
679 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
680 socket, node.node) {
681 /* Code flow error */
682 assert(socket->fd >= 0);
683
684 pthread_mutex_lock(socket->lock);
685 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session,
686 usess->consumer, socket);
687 pthread_mutex_unlock(socket->lock);
688 if (ret != LTTNG_OK) {
689 goto error;
690 }
691 }
692 }
693
694 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
695 && ksess->consumer->enabled) {
696 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
697 socket, node.node) {
698 /* Code flow error */
699 assert(socket->fd >= 0);
700
701 pthread_mutex_lock(socket->lock);
702 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session,
703 ksess->consumer, socket);
704 pthread_mutex_unlock(socket->lock);
705 if (ret != LTTNG_OK) {
706 goto error;
707 }
708 }
709 }
710
711 error:
712 rcu_read_unlock();
713 return ret;
714 }
715
716 /*
717 * Start a kernel session by opening all necessary streams.
718 */
719 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
720 {
721 int ret;
722 struct ltt_kernel_channel *kchan;
723
724 /* Open kernel metadata */
725 if (ksess->metadata == NULL) {
726 ret = kernel_open_metadata(ksess);
727 if (ret < 0) {
728 ret = LTTNG_ERR_KERN_META_FAIL;
729 goto error;
730 }
731 }
732
733 /* Open kernel metadata stream */
734 if (ksess->metadata_stream_fd < 0) {
735 ret = kernel_open_metadata_stream(ksess);
736 if (ret < 0) {
737 ERR("Kernel create metadata stream failed");
738 ret = LTTNG_ERR_KERN_STREAM_FAIL;
739 goto error;
740 }
741 }
742
743 /* For each channel */
744 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
745 if (kchan->stream_count == 0) {
746 ret = kernel_open_channel_stream(kchan);
747 if (ret < 0) {
748 ret = LTTNG_ERR_KERN_STREAM_FAIL;
749 goto error;
750 }
751 /* Update the stream global counter */
752 ksess->stream_count_global += ret;
753 }
754 }
755
756 /* Setup kernel consumer socket and send fds to it */
757 ret = init_kernel_tracing(ksess);
758 if (ret != 0) {
759 ret = LTTNG_ERR_KERN_START_FAIL;
760 goto error;
761 }
762
763 /* This start the kernel tracing */
764 ret = kernel_start_session(ksess);
765 if (ret < 0) {
766 ret = LTTNG_ERR_KERN_START_FAIL;
767 goto error;
768 }
769
770 /* Quiescent wait after starting trace */
771 kernel_wait_quiescent(kernel_tracer_fd);
772
773 ksess->started = 1;
774
775 ret = LTTNG_OK;
776
777 error:
778 return ret;
779 }
780
781 /*
782 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
783 */
784 int cmd_disable_channel(struct ltt_session *session, int domain,
785 char *channel_name)
786 {
787 int ret;
788 struct ltt_ust_session *usess;
789
790 usess = session->ust_session;
791
792 rcu_read_lock();
793
794 switch (domain) {
795 case LTTNG_DOMAIN_KERNEL:
796 {
797 ret = channel_kernel_disable(session->kernel_session,
798 channel_name);
799 if (ret != LTTNG_OK) {
800 goto error;
801 }
802
803 kernel_wait_quiescent(kernel_tracer_fd);
804 break;
805 }
806 case LTTNG_DOMAIN_UST:
807 {
808 struct ltt_ust_channel *uchan;
809 struct lttng_ht *chan_ht;
810
811 chan_ht = usess->domain_global.channels;
812
813 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
814 if (uchan == NULL) {
815 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
816 goto error;
817 }
818
819 ret = channel_ust_disable(usess, uchan);
820 if (ret != LTTNG_OK) {
821 goto error;
822 }
823 break;
824 }
825 #if 0
826 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
827 case LTTNG_DOMAIN_UST_EXEC_NAME:
828 case LTTNG_DOMAIN_UST_PID:
829 #endif
830 default:
831 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
832 goto error;
833 }
834
835 ret = LTTNG_OK;
836
837 error:
838 rcu_read_unlock();
839 return ret;
840 }
841
842 /*
843 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
844 *
845 * The wpipe arguments is used as a notifier for the kernel thread.
846 */
847 int cmd_enable_channel(struct ltt_session *session,
848 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
849 {
850 int ret;
851 struct ltt_ust_session *usess = session->ust_session;
852 struct lttng_ht *chan_ht;
853
854 assert(session);
855 assert(attr);
856 assert(domain);
857
858 DBG("Enabling channel %s for session %s", attr->name, session->name);
859
860 /*
861 * Don't try to enable a channel if the session has been started at
862 * some point in time before. The tracer does not allow it.
863 */
864 if (session->started) {
865 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
866 goto error;
867 }
868
869 rcu_read_lock();
870
871 switch (domain->type) {
872 case LTTNG_DOMAIN_KERNEL:
873 {
874 struct ltt_kernel_channel *kchan;
875
876 kchan = trace_kernel_get_channel_by_name(attr->name,
877 session->kernel_session);
878 if (kchan == NULL) {
879 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
880 } else {
881 ret = channel_kernel_enable(session->kernel_session, kchan);
882 }
883
884 if (ret != LTTNG_OK) {
885 goto error;
886 }
887
888 kernel_wait_quiescent(kernel_tracer_fd);
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 break;
904 }
905 default:
906 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
907 goto error;
908 }
909
910 error:
911 rcu_read_unlock();
912 return ret;
913 }
914
915
916 /*
917 * Command LTTNG_DISABLE_EVENT processed by the client thread.
918 */
919 int cmd_disable_event(struct ltt_session *session, int domain,
920 char *channel_name, char *event_name)
921 {
922 int ret;
923
924 rcu_read_lock();
925
926 switch (domain) {
927 case LTTNG_DOMAIN_KERNEL:
928 {
929 struct ltt_kernel_channel *kchan;
930 struct ltt_kernel_session *ksess;
931
932 ksess = session->kernel_session;
933
934 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
935 if (kchan == NULL) {
936 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
937 goto error;
938 }
939
940 ret = event_kernel_disable_tracepoint(kchan, event_name);
941 if (ret != LTTNG_OK) {
942 goto error;
943 }
944
945 kernel_wait_quiescent(kernel_tracer_fd);
946 break;
947 }
948 case LTTNG_DOMAIN_UST:
949 {
950 struct ltt_ust_channel *uchan;
951 struct ltt_ust_session *usess;
952
953 usess = session->ust_session;
954
955 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
956 channel_name);
957 if (uchan == NULL) {
958 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
959 goto error;
960 }
961
962 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
963 if (ret != LTTNG_OK) {
964 goto error;
965 }
966
967 DBG3("Disable UST event %s in channel %s completed", event_name,
968 channel_name);
969 break;
970 }
971 #if 0
972 case LTTNG_DOMAIN_UST_EXEC_NAME:
973 case LTTNG_DOMAIN_UST_PID:
974 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
975 #endif
976 default:
977 ret = LTTNG_ERR_UND;
978 goto error;
979 }
980
981 ret = LTTNG_OK;
982
983 error:
984 rcu_read_unlock();
985 return ret;
986 }
987
988 /*
989 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
990 */
991 int cmd_disable_event_all(struct ltt_session *session, int domain,
992 char *channel_name)
993 {
994 int ret;
995
996 rcu_read_lock();
997
998 switch (domain) {
999 case LTTNG_DOMAIN_KERNEL:
1000 {
1001 struct ltt_kernel_session *ksess;
1002 struct ltt_kernel_channel *kchan;
1003
1004 ksess = session->kernel_session;
1005
1006 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1007 if (kchan == NULL) {
1008 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1009 goto error;
1010 }
1011
1012 ret = event_kernel_disable_all(kchan);
1013 if (ret != LTTNG_OK) {
1014 goto error;
1015 }
1016
1017 kernel_wait_quiescent(kernel_tracer_fd);
1018 break;
1019 }
1020 case LTTNG_DOMAIN_UST:
1021 {
1022 struct ltt_ust_session *usess;
1023 struct ltt_ust_channel *uchan;
1024
1025 usess = session->ust_session;
1026
1027 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1028 channel_name);
1029 if (uchan == NULL) {
1030 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1031 goto error;
1032 }
1033
1034 ret = event_ust_disable_all_tracepoints(usess, uchan);
1035 if (ret != 0) {
1036 goto error;
1037 }
1038
1039 DBG3("Disable all UST events in channel %s completed", channel_name);
1040
1041 break;
1042 }
1043 #if 0
1044 case LTTNG_DOMAIN_UST_EXEC_NAME:
1045 case LTTNG_DOMAIN_UST_PID:
1046 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1047 #endif
1048 default:
1049 ret = LTTNG_ERR_UND;
1050 goto error;
1051 }
1052
1053 ret = LTTNG_OK;
1054
1055 error:
1056 rcu_read_unlock();
1057 return ret;
1058 }
1059
1060 /*
1061 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1062 */
1063 int cmd_add_context(struct ltt_session *session, int domain,
1064 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1065 {
1066 int ret, chan_kern_created = 0, chan_ust_created = 0;
1067
1068 switch (domain) {
1069 case LTTNG_DOMAIN_KERNEL:
1070 assert(session->kernel_session);
1071
1072 if (session->kernel_session->channel_count == 0) {
1073 /* Create default channel */
1074 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1075 if (ret != LTTNG_OK) {
1076 goto error;
1077 }
1078 chan_kern_created = 1;
1079 }
1080
1081 /* Add kernel context to kernel tracer */
1082 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1083 if (ret != LTTNG_OK) {
1084 goto error;
1085 }
1086 break;
1087 case LTTNG_DOMAIN_UST:
1088 {
1089 struct ltt_ust_session *usess = session->ust_session;
1090 assert(usess);
1091
1092 unsigned int chan_count =
1093 lttng_ht_get_count(usess->domain_global.channels);
1094 if (chan_count == 0) {
1095 struct lttng_channel *attr;
1096 /* Create default channel */
1097 attr = channel_new_default_attr(domain, usess->buffer_type);
1098 if (attr == NULL) {
1099 ret = LTTNG_ERR_FATAL;
1100 goto error;
1101 }
1102
1103 ret = channel_ust_create(usess, attr, usess->buffer_type);
1104 if (ret != LTTNG_OK) {
1105 free(attr);
1106 goto error;
1107 }
1108 free(attr);
1109 chan_ust_created = 1;
1110 }
1111
1112 ret = context_ust_add(usess, domain, ctx, channel_name);
1113 if (ret != LTTNG_OK) {
1114 goto error;
1115 }
1116 break;
1117 }
1118 #if 0
1119 case LTTNG_DOMAIN_UST_EXEC_NAME:
1120 case LTTNG_DOMAIN_UST_PID:
1121 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1122 #endif
1123 default:
1124 ret = LTTNG_ERR_UND;
1125 goto error;
1126 }
1127
1128 return LTTNG_OK;
1129
1130 error:
1131 if (chan_kern_created) {
1132 struct ltt_kernel_channel *kchan =
1133 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1134 session->kernel_session);
1135 /* Created previously, this should NOT fail. */
1136 assert(kchan);
1137 kernel_destroy_channel(kchan);
1138 }
1139
1140 if (chan_ust_created) {
1141 struct ltt_ust_channel *uchan =
1142 trace_ust_find_channel_by_name(
1143 session->ust_session->domain_global.channels,
1144 DEFAULT_CHANNEL_NAME);
1145 /* Created previously, this should NOT fail. */
1146 assert(uchan);
1147 /* Remove from the channel list of the session. */
1148 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1149 uchan);
1150 trace_ust_destroy_channel(uchan);
1151 }
1152 return ret;
1153 }
1154
1155 /*
1156 * Command LTTNG_ENABLE_EVENT processed by the client thread.
1157 */
1158 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1159 char *channel_name, struct lttng_event *event,
1160 struct lttng_filter_bytecode *filter, int wpipe)
1161 {
1162 int ret, channel_created = 0;
1163 struct lttng_channel *attr;
1164
1165 assert(session);
1166 assert(event);
1167 assert(channel_name);
1168
1169 rcu_read_lock();
1170
1171 switch (domain->type) {
1172 case LTTNG_DOMAIN_KERNEL:
1173 {
1174 struct ltt_kernel_channel *kchan;
1175
1176 kchan = trace_kernel_get_channel_by_name(channel_name,
1177 session->kernel_session);
1178 if (kchan == NULL) {
1179 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1180 LTTNG_BUFFER_GLOBAL);
1181 if (attr == NULL) {
1182 ret = LTTNG_ERR_FATAL;
1183 goto error;
1184 }
1185 strncpy(attr->name, channel_name, sizeof(attr->name));
1186
1187 ret = cmd_enable_channel(session, domain, attr, wpipe);
1188 if (ret != LTTNG_OK) {
1189 free(attr);
1190 goto error;
1191 }
1192 free(attr);
1193
1194 channel_created = 1;
1195 }
1196
1197 /* Get the newly created kernel channel pointer */
1198 kchan = trace_kernel_get_channel_by_name(channel_name,
1199 session->kernel_session);
1200 if (kchan == NULL) {
1201 /* This sould not happen... */
1202 ret = LTTNG_ERR_FATAL;
1203 goto error;
1204 }
1205
1206 ret = event_kernel_enable_tracepoint(kchan, event);
1207 if (ret != LTTNG_OK) {
1208 if (channel_created) {
1209 /* Let's not leak a useless channel. */
1210 kernel_destroy_channel(kchan);
1211 }
1212 goto error;
1213 }
1214
1215 kernel_wait_quiescent(kernel_tracer_fd);
1216 break;
1217 }
1218 case LTTNG_DOMAIN_UST:
1219 {
1220 struct ltt_ust_channel *uchan;
1221 struct ltt_ust_session *usess = session->ust_session;
1222
1223 assert(usess);
1224
1225 /* Get channel from global UST domain */
1226 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1227 channel_name);
1228 if (uchan == NULL) {
1229 /* Create default channel */
1230 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1231 usess->buffer_type);
1232 if (attr == NULL) {
1233 ret = LTTNG_ERR_FATAL;
1234 goto error;
1235 }
1236 strncpy(attr->name, channel_name, sizeof(attr->name));
1237
1238 ret = cmd_enable_channel(session, domain, attr, wpipe);
1239 if (ret != LTTNG_OK) {
1240 free(attr);
1241 goto error;
1242 }
1243 free(attr);
1244
1245 /* Get the newly created channel reference back */
1246 uchan = trace_ust_find_channel_by_name(
1247 usess->domain_global.channels, channel_name);
1248 assert(uchan);
1249 }
1250
1251 /* At this point, the session and channel exist on the tracer */
1252 ret = event_ust_enable_tracepoint(usess, uchan, event, filter);
1253 if (ret != LTTNG_OK) {
1254 goto error;
1255 }
1256 break;
1257 }
1258 #if 0
1259 case LTTNG_DOMAIN_UST_EXEC_NAME:
1260 case LTTNG_DOMAIN_UST_PID:
1261 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1262 #endif
1263 default:
1264 ret = LTTNG_ERR_UND;
1265 goto error;
1266 }
1267
1268 ret = LTTNG_OK;
1269
1270 error:
1271 rcu_read_unlock();
1272 return ret;
1273 }
1274
1275 /*
1276 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
1277 */
1278 int cmd_enable_event_all(struct ltt_session *session,
1279 struct lttng_domain *domain, char *channel_name, int event_type,
1280 struct lttng_filter_bytecode *filter, int wpipe)
1281 {
1282 int ret;
1283 struct lttng_channel *attr;
1284
1285 assert(session);
1286 assert(channel_name);
1287
1288 rcu_read_lock();
1289
1290 switch (domain->type) {
1291 case LTTNG_DOMAIN_KERNEL:
1292 {
1293 struct ltt_kernel_channel *kchan;
1294
1295 assert(session->kernel_session);
1296
1297 kchan = trace_kernel_get_channel_by_name(channel_name,
1298 session->kernel_session);
1299 if (kchan == NULL) {
1300 /* Create default channel */
1301 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1302 LTTNG_BUFFER_GLOBAL);
1303 if (attr == NULL) {
1304 ret = LTTNG_ERR_FATAL;
1305 goto error;
1306 }
1307 strncpy(attr->name, channel_name, sizeof(attr->name));
1308
1309 ret = cmd_enable_channel(session, domain, attr, wpipe);
1310 if (ret != LTTNG_OK) {
1311 free(attr);
1312 goto error;
1313 }
1314 free(attr);
1315
1316 /* Get the newly created kernel channel pointer */
1317 kchan = trace_kernel_get_channel_by_name(channel_name,
1318 session->kernel_session);
1319 assert(kchan);
1320 }
1321
1322 switch (event_type) {
1323 case LTTNG_EVENT_SYSCALL:
1324 ret = event_kernel_enable_all_syscalls(kchan, kernel_tracer_fd);
1325 break;
1326 case LTTNG_EVENT_TRACEPOINT:
1327 /*
1328 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
1329 * events already registered to the channel.
1330 */
1331 ret = event_kernel_enable_all_tracepoints(kchan, kernel_tracer_fd);
1332 break;
1333 case LTTNG_EVENT_ALL:
1334 /* Enable syscalls and tracepoints */
1335 ret = event_kernel_enable_all(kchan, kernel_tracer_fd);
1336 break;
1337 default:
1338 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1339 goto error;
1340 }
1341
1342 /* Manage return value */
1343 if (ret != LTTNG_OK) {
1344 /*
1345 * On error, cmd_enable_channel call will take care of destroying
1346 * the created channel if it was needed.
1347 */
1348 goto error;
1349 }
1350
1351 kernel_wait_quiescent(kernel_tracer_fd);
1352 break;
1353 }
1354 case LTTNG_DOMAIN_UST:
1355 {
1356 struct ltt_ust_channel *uchan;
1357 struct ltt_ust_session *usess = session->ust_session;
1358
1359 assert(usess);
1360
1361 /* Get channel from global UST domain */
1362 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1363 channel_name);
1364 if (uchan == NULL) {
1365 /* Create default channel */
1366 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1367 usess->buffer_type);
1368 if (attr == NULL) {
1369 ret = LTTNG_ERR_FATAL;
1370 goto error;
1371 }
1372 strncpy(attr->name, channel_name, sizeof(attr->name));
1373
1374 ret = cmd_enable_channel(session, domain, attr, wpipe);
1375 if (ret != LTTNG_OK) {
1376 free(attr);
1377 goto error;
1378 }
1379 free(attr);
1380
1381 /* Get the newly created channel reference back */
1382 uchan = trace_ust_find_channel_by_name(
1383 usess->domain_global.channels, channel_name);
1384 assert(uchan);
1385 }
1386
1387 /* At this point, the session and channel exist on the tracer */
1388
1389 switch (event_type) {
1390 case LTTNG_EVENT_ALL:
1391 case LTTNG_EVENT_TRACEPOINT:
1392 ret = event_ust_enable_all_tracepoints(usess, uchan, filter);
1393 if (ret != LTTNG_OK) {
1394 goto error;
1395 }
1396 break;
1397 default:
1398 ret = LTTNG_ERR_UST_ENABLE_FAIL;
1399 goto error;
1400 }
1401
1402 /* Manage return value */
1403 if (ret != LTTNG_OK) {
1404 goto error;
1405 }
1406
1407 break;
1408 }
1409 #if 0
1410 case LTTNG_DOMAIN_UST_EXEC_NAME:
1411 case LTTNG_DOMAIN_UST_PID:
1412 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
1413 #endif
1414 default:
1415 ret = LTTNG_ERR_UND;
1416 goto error;
1417 }
1418
1419 ret = LTTNG_OK;
1420
1421 error:
1422 rcu_read_unlock();
1423 return ret;
1424 }
1425
1426
1427 /*
1428 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1429 */
1430 ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
1431 {
1432 int ret;
1433 ssize_t nb_events = 0;
1434
1435 switch (domain) {
1436 case LTTNG_DOMAIN_KERNEL:
1437 nb_events = kernel_list_events(kernel_tracer_fd, events);
1438 if (nb_events < 0) {
1439 ret = LTTNG_ERR_KERN_LIST_FAIL;
1440 goto error;
1441 }
1442 break;
1443 case LTTNG_DOMAIN_UST:
1444 nb_events = ust_app_list_events(events);
1445 if (nb_events < 0) {
1446 ret = LTTNG_ERR_UST_LIST_FAIL;
1447 goto error;
1448 }
1449 break;
1450 default:
1451 ret = LTTNG_ERR_UND;
1452 goto error;
1453 }
1454
1455 return nb_events;
1456
1457 error:
1458 /* Return negative value to differentiate return code */
1459 return -ret;
1460 }
1461
1462 /*
1463 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1464 */
1465 ssize_t cmd_list_tracepoint_fields(int domain,
1466 struct lttng_event_field **fields)
1467 {
1468 int ret;
1469 ssize_t nb_fields = 0;
1470
1471 switch (domain) {
1472 case LTTNG_DOMAIN_UST:
1473 nb_fields = ust_app_list_event_fields(fields);
1474 if (nb_fields < 0) {
1475 ret = LTTNG_ERR_UST_LIST_FAIL;
1476 goto error;
1477 }
1478 break;
1479 case LTTNG_DOMAIN_KERNEL:
1480 default: /* fall-through */
1481 ret = LTTNG_ERR_UND;
1482 goto error;
1483 }
1484
1485 return nb_fields;
1486
1487 error:
1488 /* Return negative value to differentiate return code */
1489 return -ret;
1490 }
1491
1492 /*
1493 * Command LTTNG_START_TRACE processed by the client thread.
1494 */
1495 int cmd_start_trace(struct ltt_session *session)
1496 {
1497 int ret;
1498 struct ltt_kernel_session *ksession;
1499 struct ltt_ust_session *usess;
1500
1501 assert(session);
1502
1503 /* Ease our life a bit ;) */
1504 ksession = session->kernel_session;
1505 usess = session->ust_session;
1506
1507 if (session->enabled) {
1508 /* Already started. */
1509 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1510 goto error;
1511 }
1512
1513 session->enabled = 1;
1514
1515 /* Kernel tracing */
1516 if (ksession != NULL) {
1517 ret = start_kernel_session(ksession, kernel_tracer_fd);
1518 if (ret != LTTNG_OK) {
1519 goto error;
1520 }
1521 }
1522
1523 /* Flag session that trace should start automatically */
1524 if (usess) {
1525 usess->start_trace = 1;
1526
1527 ret = ust_app_start_trace_all(usess);
1528 if (ret < 0) {
1529 ret = LTTNG_ERR_UST_START_FAIL;
1530 goto error;
1531 }
1532 }
1533
1534 session->started = 1;
1535
1536 ret = LTTNG_OK;
1537
1538 error:
1539 return ret;
1540 }
1541
1542 /*
1543 * Command LTTNG_STOP_TRACE processed by the client thread.
1544 */
1545 int cmd_stop_trace(struct ltt_session *session)
1546 {
1547 int ret;
1548 struct ltt_kernel_channel *kchan;
1549 struct ltt_kernel_session *ksession;
1550 struct ltt_ust_session *usess;
1551
1552 assert(session);
1553
1554 /* Short cut */
1555 ksession = session->kernel_session;
1556 usess = session->ust_session;
1557
1558 if (!session->enabled) {
1559 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
1560 goto error;
1561 }
1562
1563 session->enabled = 0;
1564
1565 /* Kernel tracer */
1566 if (ksession && ksession->started) {
1567 DBG("Stop kernel tracing");
1568
1569 /* Flush metadata if exist */
1570 if (ksession->metadata_stream_fd >= 0) {
1571 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
1572 if (ret < 0) {
1573 ERR("Kernel metadata flush failed");
1574 }
1575 }
1576
1577 /* Flush all buffers before stopping */
1578 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
1579 ret = kernel_flush_buffer(kchan);
1580 if (ret < 0) {
1581 ERR("Kernel flush buffer error");
1582 }
1583 }
1584
1585 ret = kernel_stop_session(ksession);
1586 if (ret < 0) {
1587 ret = LTTNG_ERR_KERN_STOP_FAIL;
1588 goto error;
1589 }
1590
1591 kernel_wait_quiescent(kernel_tracer_fd);
1592
1593 ksession->started = 0;
1594 }
1595
1596 if (usess && usess->start_trace) {
1597 usess->start_trace = 0;
1598
1599 ret = ust_app_stop_trace_all(usess);
1600 if (ret < 0) {
1601 ret = LTTNG_ERR_UST_STOP_FAIL;
1602 goto error;
1603 }
1604 }
1605
1606 ret = LTTNG_OK;
1607
1608 error:
1609 return ret;
1610 }
1611
1612 /*
1613 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
1614 */
1615 int cmd_set_consumer_uri(int domain, struct ltt_session *session,
1616 size_t nb_uri, struct lttng_uri *uris)
1617 {
1618 int ret, i;
1619 struct ltt_kernel_session *ksess = session->kernel_session;
1620 struct ltt_ust_session *usess = session->ust_session;
1621 struct consumer_output *consumer = NULL;
1622
1623 assert(session);
1624 assert(uris);
1625 assert(nb_uri > 0);
1626
1627 /* Can't enable consumer after session started. */
1628 if (session->enabled) {
1629 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1630 goto error;
1631 }
1632
1633 /*
1634 * This case switch makes sure the domain session has a temporary consumer
1635 * so the URL can be set.
1636 */
1637 switch (domain) {
1638 case 0:
1639 /* Code flow error. A session MUST always have a consumer object */
1640 assert(session->consumer);
1641 /*
1642 * The URL will be added to the tracing session consumer instead of a
1643 * specific domain consumer.
1644 */
1645 consumer = session->consumer;
1646 break;
1647 case LTTNG_DOMAIN_KERNEL:
1648 /* Code flow error if we don't have a kernel session here. */
1649 assert(ksess);
1650 assert(ksess->consumer);
1651 consumer = ksess->consumer;
1652 break;
1653 case LTTNG_DOMAIN_UST:
1654 /* Code flow error if we don't have a kernel session here. */
1655 assert(usess);
1656 assert(usess->consumer);
1657 consumer = usess->consumer;
1658 break;
1659 }
1660
1661 for (i = 0; i < nb_uri; i++) {
1662 ret = add_uri_to_consumer(consumer, &uris[i], domain, session->name);
1663 if (ret != LTTNG_OK) {
1664 goto error;
1665 }
1666 }
1667
1668 /* All good! */
1669 ret = LTTNG_OK;
1670
1671 error:
1672 return ret;
1673 }
1674
1675 /*
1676 * Command LTTNG_CREATE_SESSION processed by the client thread.
1677 */
1678 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
1679 size_t nb_uri, lttng_sock_cred *creds)
1680 {
1681 int ret;
1682 struct ltt_session *session;
1683
1684 assert(name);
1685
1686 /* No URIs is not possible. */
1687 if (uris == NULL) {
1688 ret = LTTNG_ERR_SESSION_FAIL;
1689 goto session_error;
1690 }
1691
1692 /*
1693 * Verify if the session already exist
1694 *
1695 * XXX: There is no need for the session lock list here since the caller
1696 * (process_client_msg) is holding it. We might want to change that so a
1697 * single command does not lock the entire session list.
1698 */
1699 session = session_find_by_name(name);
1700 if (session != NULL) {
1701 ret = LTTNG_ERR_EXIST_SESS;
1702 goto find_error;
1703 }
1704
1705 /* Create tracing session in the registry */
1706 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
1707 LTTNG_SOCK_GET_GID_CRED(creds));
1708 if (ret != LTTNG_OK) {
1709 goto session_error;
1710 }
1711
1712 /*
1713 * Get the newly created session pointer back
1714 *
1715 * XXX: There is no need for the session lock list here since the caller
1716 * (process_client_msg) is holding it. We might want to change that so a
1717 * single command does not lock the entire session list.
1718 */
1719 session = session_find_by_name(name);
1720 assert(session);
1721
1722 /* Create default consumer output for the session not yet created. */
1723 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
1724 if (session->consumer == NULL) {
1725 ret = LTTNG_ERR_FATAL;
1726 goto consumer_error;
1727 }
1728
1729 ret = cmd_set_consumer_uri(0, session, nb_uri, uris);
1730 if (ret != LTTNG_OK) {
1731 goto consumer_error;
1732 }
1733
1734 session->consumer->enabled = 1;
1735
1736 return LTTNG_OK;
1737
1738 consumer_error:
1739 session_destroy(session);
1740 session_error:
1741 find_error:
1742 return ret;
1743 }
1744
1745 /*
1746 * Command LTTNG_DESTROY_SESSION processed by the client thread.
1747 */
1748 int cmd_destroy_session(struct ltt_session *session, int wpipe)
1749 {
1750 int ret;
1751 struct ltt_ust_session *usess;
1752 struct ltt_kernel_session *ksess;
1753
1754 /* Safety net */
1755 assert(session);
1756
1757 usess = session->ust_session;
1758 ksess = session->kernel_session;
1759
1760 /* Clean kernel session teardown */
1761 kernel_destroy_session(ksess);
1762
1763 /* UST session teardown */
1764 if (usess) {
1765 /* Close any relayd session */
1766 consumer_output_send_destroy_relayd(usess->consumer);
1767
1768 /* Destroy every UST application related to this session. */
1769 ret = ust_app_destroy_trace_all(usess);
1770 if (ret) {
1771 ERR("Error in ust_app_destroy_trace_all");
1772 }
1773
1774 /* Clean up the rest. */
1775 trace_ust_destroy_session(usess);
1776 }
1777
1778 /*
1779 * Must notify the kernel thread here to update it's poll set in order to
1780 * remove the channel(s)' fd just destroyed.
1781 */
1782 ret = notify_thread_pipe(wpipe);
1783 if (ret < 0) {
1784 PERROR("write kernel poll pipe");
1785 }
1786
1787 ret = session_destroy(session);
1788
1789 return ret;
1790 }
1791
1792 /*
1793 * Command LTTNG_CALIBRATE processed by the client thread.
1794 */
1795 int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
1796 {
1797 int ret;
1798
1799 switch (domain) {
1800 case LTTNG_DOMAIN_KERNEL:
1801 {
1802 struct lttng_kernel_calibrate kcalibrate;
1803
1804 kcalibrate.type = calibrate->type;
1805 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
1806 if (ret < 0) {
1807 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
1808 goto error;
1809 }
1810 break;
1811 }
1812 case LTTNG_DOMAIN_UST:
1813 {
1814 struct lttng_ust_calibrate ucalibrate;
1815
1816 ucalibrate.type = calibrate->type;
1817 ret = ust_app_calibrate_glb(&ucalibrate);
1818 if (ret < 0) {
1819 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
1820 goto error;
1821 }
1822 break;
1823 }
1824 default:
1825 ret = LTTNG_ERR_UND;
1826 goto error;
1827 }
1828
1829 ret = LTTNG_OK;
1830
1831 error:
1832 return ret;
1833 }
1834
1835 /*
1836 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
1837 */
1838 int cmd_register_consumer(struct ltt_session *session, int domain,
1839 const char *sock_path, struct consumer_data *cdata)
1840 {
1841 int ret, sock;
1842 struct consumer_socket *socket = NULL;
1843
1844 assert(session);
1845 assert(cdata);
1846 assert(sock_path);
1847
1848 switch (domain) {
1849 case LTTNG_DOMAIN_KERNEL:
1850 {
1851 struct ltt_kernel_session *ksess = session->kernel_session;
1852
1853 assert(ksess);
1854
1855 /* Can't register a consumer if there is already one */
1856 if (ksess->consumer_fds_sent != 0) {
1857 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
1858 goto error;
1859 }
1860
1861 sock = lttcomm_connect_unix_sock(sock_path);
1862 if (sock < 0) {
1863 ret = LTTNG_ERR_CONNECT_FAIL;
1864 goto error;
1865 }
1866
1867 socket = consumer_allocate_socket(sock);
1868 if (socket == NULL) {
1869 ret = close(sock);
1870 if (ret < 0) {
1871 PERROR("close register consumer");
1872 }
1873 ret = LTTNG_ERR_FATAL;
1874 goto error;
1875 }
1876
1877 socket->lock = zmalloc(sizeof(pthread_mutex_t));
1878 if (socket->lock == NULL) {
1879 PERROR("zmalloc pthread mutex");
1880 ret = LTTNG_ERR_FATAL;
1881 goto error;
1882 }
1883 pthread_mutex_init(socket->lock, NULL);
1884 socket->registered = 1;
1885
1886 rcu_read_lock();
1887 consumer_add_socket(socket, ksess->consumer);
1888 rcu_read_unlock();
1889
1890 pthread_mutex_lock(&cdata->pid_mutex);
1891 cdata->pid = -1;
1892 pthread_mutex_unlock(&cdata->pid_mutex);
1893
1894 break;
1895 }
1896 default:
1897 /* TODO: Userspace tracing */
1898 ret = LTTNG_ERR_UND;
1899 goto error;
1900 }
1901
1902 return LTTNG_OK;
1903
1904 error:
1905 if (socket) {
1906 consumer_destroy_socket(socket);
1907 }
1908 return ret;
1909 }
1910
1911 /*
1912 * Command LTTNG_LIST_DOMAINS processed by the client thread.
1913 */
1914 ssize_t cmd_list_domains(struct ltt_session *session,
1915 struct lttng_domain **domains)
1916 {
1917 int ret, index = 0;
1918 ssize_t nb_dom = 0;
1919
1920 if (session->kernel_session != NULL) {
1921 DBG3("Listing domains found kernel domain");
1922 nb_dom++;
1923 }
1924
1925 if (session->ust_session != NULL) {
1926 DBG3("Listing domains found UST global domain");
1927 nb_dom++;
1928 }
1929
1930 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
1931 if (*domains == NULL) {
1932 ret = LTTNG_ERR_FATAL;
1933 goto error;
1934 }
1935
1936 if (session->kernel_session != NULL) {
1937 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
1938 index++;
1939 }
1940
1941 if (session->ust_session != NULL) {
1942 (*domains)[index].type = LTTNG_DOMAIN_UST;
1943 (*domains)[index].buf_type = session->ust_session->buffer_type;
1944 index++;
1945 }
1946
1947 return nb_dom;
1948
1949 error:
1950 /* Return negative value to differentiate return code */
1951 return -ret;
1952 }
1953
1954
1955 /*
1956 * Command LTTNG_LIST_CHANNELS processed by the client thread.
1957 */
1958 ssize_t cmd_list_channels(int domain, struct ltt_session *session,
1959 struct lttng_channel **channels)
1960 {
1961 int ret;
1962 ssize_t nb_chan = 0;
1963
1964 switch (domain) {
1965 case LTTNG_DOMAIN_KERNEL:
1966 if (session->kernel_session != NULL) {
1967 nb_chan = session->kernel_session->channel_count;
1968 }
1969 DBG3("Number of kernel channels %zd", nb_chan);
1970 if (nb_chan <= 0) {
1971 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1972 }
1973 break;
1974 case LTTNG_DOMAIN_UST:
1975 if (session->ust_session != NULL) {
1976 nb_chan = lttng_ht_get_count(
1977 session->ust_session->domain_global.channels);
1978 }
1979 DBG3("Number of UST global channels %zd", nb_chan);
1980 if (nb_chan <= 0) {
1981 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1982 }
1983 break;
1984 default:
1985 *channels = NULL;
1986 ret = LTTNG_ERR_UND;
1987 goto error;
1988 }
1989
1990 if (nb_chan > 0) {
1991 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
1992 if (*channels == NULL) {
1993 ret = LTTNG_ERR_FATAL;
1994 goto error;
1995 }
1996
1997 list_lttng_channels(domain, session, *channels);
1998 } else {
1999 *channels = NULL;
2000 /* Ret value was set in the domain switch case */
2001 goto error;
2002 }
2003
2004 return nb_chan;
2005
2006 error:
2007 /* Return negative value to differentiate return code */
2008 return -ret;
2009 }
2010
2011 /*
2012 * Command LTTNG_LIST_EVENTS processed by the client thread.
2013 */
2014 ssize_t cmd_list_events(int domain, struct ltt_session *session,
2015 char *channel_name, struct lttng_event **events)
2016 {
2017 int ret = 0;
2018 ssize_t nb_event = 0;
2019
2020 switch (domain) {
2021 case LTTNG_DOMAIN_KERNEL:
2022 if (session->kernel_session != NULL) {
2023 nb_event = list_lttng_kernel_events(channel_name,
2024 session->kernel_session, events);
2025 }
2026 break;
2027 case LTTNG_DOMAIN_UST:
2028 {
2029 if (session->ust_session != NULL) {
2030 nb_event = list_lttng_ust_global_events(channel_name,
2031 &session->ust_session->domain_global, events);
2032 }
2033 break;
2034 }
2035 default:
2036 ret = LTTNG_ERR_UND;
2037 goto error;
2038 }
2039
2040 return nb_event;
2041
2042 error:
2043 /* Return negative value to differentiate return code */
2044 return -ret;
2045 }
2046
2047 /*
2048 * Using the session list, filled a lttng_session array to send back to the
2049 * client for session listing.
2050 *
2051 * The session list lock MUST be acquired before calling this function. Use
2052 * session_lock_list() and session_unlock_list().
2053 */
2054 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2055 gid_t gid)
2056 {
2057 int ret;
2058 unsigned int i = 0;
2059 struct ltt_session *session;
2060 struct ltt_session_list *list = session_get_list();
2061
2062 DBG("Getting all available session for UID %d GID %d",
2063 uid, gid);
2064 /*
2065 * Iterate over session list and append data after the control struct in
2066 * the buffer.
2067 */
2068 cds_list_for_each_entry(session, &list->head, list) {
2069 /*
2070 * Only list the sessions the user can control.
2071 */
2072 if (!session_access_ok(session, uid, gid)) {
2073 continue;
2074 }
2075
2076 struct ltt_kernel_session *ksess = session->kernel_session;
2077 struct ltt_ust_session *usess = session->ust_session;
2078
2079 if (session->consumer->type == CONSUMER_DST_NET ||
2080 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2081 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2082 ret = build_network_session_path(sessions[i].path,
2083 sizeof(sessions[i].path), session);
2084 } else {
2085 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
2086 session->consumer->dst.trace_path);
2087 }
2088 if (ret < 0) {
2089 PERROR("snprintf session path");
2090 continue;
2091 }
2092
2093 strncpy(sessions[i].name, session->name, NAME_MAX);
2094 sessions[i].name[NAME_MAX - 1] = '\0';
2095 sessions[i].enabled = session->enabled;
2096 i++;
2097 }
2098 }
2099
2100 /*
2101 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2102 * ready for trace analysis (or anykind of reader) or else 1 for pending data.
2103 */
2104 int cmd_data_pending(struct ltt_session *session)
2105 {
2106 int ret;
2107 struct ltt_kernel_session *ksess = session->kernel_session;
2108 struct ltt_ust_session *usess = session->ust_session;
2109
2110 assert(session);
2111
2112 /* Session MUST be stopped to ask for data availability. */
2113 if (session->enabled) {
2114 ret = LTTNG_ERR_SESSION_STARTED;
2115 goto error;
2116 }
2117
2118 if (ksess && ksess->consumer) {
2119 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2120 if (ret == 1) {
2121 /* Data is still being extracted for the kernel. */
2122 goto error;
2123 }
2124 }
2125
2126 if (usess && usess->consumer) {
2127 ret = consumer_is_data_pending(usess->id, usess->consumer);
2128 if (ret == 1) {
2129 /* Data is still being extracted for the kernel. */
2130 goto error;
2131 }
2132 }
2133
2134 /* Data is ready to be read by a viewer */
2135 ret = 0;
2136
2137 error:
2138 return ret;
2139 }
2140
2141 /*
2142 * Init command subsystem.
2143 */
2144 void cmd_init(void)
2145 {
2146 /*
2147 * Set network sequence index to 1 for streams to match a relayd
2148 * socket on the consumer side.
2149 */
2150 pthread_mutex_lock(&relayd_net_seq_idx_lock);
2151 relayd_net_seq_idx = 1;
2152 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
2153
2154 DBG("Command subsystem initialized");
2155 }
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