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