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