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Prevent disable event on internal UST events
[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 #include "agent.h"
42
43 #include "cmd.h"
44
45 /*
46 * Used to keep a unique index for each relayd socket created where this value
47 * is associated with streams on the consumer so it can match the right relayd
48 * to send to. It must be accessed with the relayd_net_seq_idx_lock
49 * held.
50 */
51 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
52 static uint64_t relayd_net_seq_idx;
53
54 static int validate_event_name(const char *);
55 static int validate_ust_event_name(const char *);
56 static int cmd_enable_event_internal(struct ltt_session *session,
57 struct lttng_domain *domain,
58 char *channel_name, struct lttng_event *event,
59 char *filter_expression,
60 struct lttng_filter_bytecode *filter,
61 struct lttng_event_exclusion *exclusion,
62 int wpipe);
63
64 /*
65 * Create a session path used by list_lttng_sessions for the case that the
66 * session consumer is on the network.
67 */
68 static int build_network_session_path(char *dst, size_t size,
69 struct ltt_session *session)
70 {
71 int ret, kdata_port, udata_port;
72 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
73 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
74
75 assert(session);
76 assert(dst);
77
78 memset(tmp_urls, 0, sizeof(tmp_urls));
79 memset(tmp_uurl, 0, sizeof(tmp_uurl));
80
81 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
82
83 if (session->kernel_session && session->kernel_session->consumer) {
84 kuri = &session->kernel_session->consumer->dst.net.control;
85 kdata_port = session->kernel_session->consumer->dst.net.data.port;
86 }
87
88 if (session->ust_session && session->ust_session->consumer) {
89 uuri = &session->ust_session->consumer->dst.net.control;
90 udata_port = session->ust_session->consumer->dst.net.data.port;
91 }
92
93 if (uuri == NULL && kuri == NULL) {
94 uri = &session->consumer->dst.net.control;
95 kdata_port = session->consumer->dst.net.data.port;
96 } else if (kuri && uuri) {
97 ret = uri_compare(kuri, uuri);
98 if (ret) {
99 /* Not Equal */
100 uri = kuri;
101 /* Build uuri URL string */
102 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
103 if (ret < 0) {
104 goto error;
105 }
106 } else {
107 uri = kuri;
108 }
109 } else if (kuri && uuri == NULL) {
110 uri = kuri;
111 } else if (uuri && kuri == NULL) {
112 uri = uuri;
113 }
114
115 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
116 if (ret < 0) {
117 goto error;
118 }
119
120 /*
121 * Do we have a UST url set. If yes, this means we have both kernel and UST
122 * to print.
123 */
124 if (*tmp_uurl != '\0') {
125 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
126 tmp_urls, kdata_port, tmp_uurl, udata_port);
127 } else {
128 int dport;
129 if (kuri || (!kuri && !uuri)) {
130 dport = kdata_port;
131 } else {
132 /* No kernel URI, use the UST port. */
133 dport = udata_port;
134 }
135 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
136 }
137
138 error:
139 return ret;
140 }
141
142 /*
143 * Fill lttng_channel array of all channels.
144 */
145 static void list_lttng_channels(int domain, struct ltt_session *session,
146 struct lttng_channel *channels)
147 {
148 int i = 0;
149 struct ltt_kernel_channel *kchan;
150
151 DBG("Listing channels for session %s", session->name);
152
153 switch (domain) {
154 case LTTNG_DOMAIN_KERNEL:
155 /* Kernel channels */
156 if (session->kernel_session != NULL) {
157 cds_list_for_each_entry(kchan,
158 &session->kernel_session->channel_list.head, list) {
159 /* Copy lttng_channel struct to array */
160 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
161 channels[i].enabled = kchan->enabled;
162 i++;
163 }
164 }
165 break;
166 case LTTNG_DOMAIN_UST:
167 {
168 struct lttng_ht_iter iter;
169 struct ltt_ust_channel *uchan;
170
171 rcu_read_lock();
172 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
173 &iter.iter, uchan, node.node) {
174 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
175 channels[i].attr.overwrite = uchan->attr.overwrite;
176 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
177 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
178 channels[i].attr.switch_timer_interval =
179 uchan->attr.switch_timer_interval;
180 channels[i].attr.read_timer_interval =
181 uchan->attr.read_timer_interval;
182 channels[i].enabled = uchan->enabled;
183 channels[i].attr.tracefile_size = uchan->tracefile_size;
184 channels[i].attr.tracefile_count = uchan->tracefile_count;
185 switch (uchan->attr.output) {
186 case LTTNG_UST_MMAP:
187 default:
188 channels[i].attr.output = LTTNG_EVENT_MMAP;
189 break;
190 }
191 i++;
192 }
193 rcu_read_unlock();
194 break;
195 }
196 default:
197 break;
198 }
199 }
200
201 /*
202 * Create a list of agent domain events.
203 *
204 * Return number of events in list on success or else a negative value.
205 */
206 static int list_lttng_agent_events(struct agent *agt,
207 struct lttng_event **events)
208 {
209 int i = 0, ret = 0;
210 unsigned int nb_event = 0;
211 struct agent_event *event;
212 struct lttng_event *tmp_events;
213 struct lttng_ht_iter iter;
214
215 assert(agt);
216 assert(events);
217
218 DBG3("Listing agent events");
219
220 rcu_read_lock();
221 nb_event = lttng_ht_get_count(agt->events);
222 rcu_read_unlock();
223 if (nb_event == 0) {
224 ret = nb_event;
225 goto error;
226 }
227
228 tmp_events = zmalloc(nb_event * sizeof(*tmp_events));
229 if (!tmp_events) {
230 PERROR("zmalloc agent events session");
231 ret = -LTTNG_ERR_FATAL;
232 goto error;
233 }
234
235 rcu_read_lock();
236 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
237 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
238 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
239 tmp_events[i].enabled = event->enabled;
240 tmp_events[i].loglevel = event->loglevel;
241 tmp_events[i].loglevel_type = event->loglevel_type;
242 i++;
243 }
244 rcu_read_unlock();
245
246 *events = tmp_events;
247 ret = nb_event;
248
249 error:
250 assert(nb_event == i);
251 return ret;
252 }
253
254 /*
255 * Create a list of ust global domain events.
256 */
257 static int list_lttng_ust_global_events(char *channel_name,
258 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
259 {
260 int i = 0, ret = 0;
261 unsigned int nb_event = 0;
262 struct lttng_ht_iter iter;
263 struct lttng_ht_node_str *node;
264 struct ltt_ust_channel *uchan;
265 struct ltt_ust_event *uevent;
266 struct lttng_event *tmp;
267
268 DBG("Listing UST global events for channel %s", channel_name);
269
270 rcu_read_lock();
271
272 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
273 node = lttng_ht_iter_get_node_str(&iter);
274 if (node == NULL) {
275 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
276 goto error;
277 }
278
279 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
280
281 nb_event = lttng_ht_get_count(uchan->events);
282 if (nb_event == 0) {
283 ret = nb_event;
284 goto error;
285 }
286
287 DBG3("Listing UST global %d events", nb_event);
288
289 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
290 if (tmp == NULL) {
291 ret = LTTNG_ERR_FATAL;
292 goto error;
293 }
294
295 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
296 if (uevent->internal) {
297 /* This event should remain hidden from clients */
298 nb_event--;
299 continue;
300 }
301 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
302 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
303 tmp[i].enabled = uevent->enabled;
304
305 switch (uevent->attr.instrumentation) {
306 case LTTNG_UST_TRACEPOINT:
307 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
308 break;
309 case LTTNG_UST_PROBE:
310 tmp[i].type = LTTNG_EVENT_PROBE;
311 break;
312 case LTTNG_UST_FUNCTION:
313 tmp[i].type = LTTNG_EVENT_FUNCTION;
314 break;
315 }
316
317 tmp[i].loglevel = uevent->attr.loglevel;
318 switch (uevent->attr.loglevel_type) {
319 case LTTNG_UST_LOGLEVEL_ALL:
320 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
321 break;
322 case LTTNG_UST_LOGLEVEL_RANGE:
323 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
324 break;
325 case LTTNG_UST_LOGLEVEL_SINGLE:
326 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
327 break;
328 }
329 if (uevent->filter) {
330 tmp[i].filter = 1;
331 }
332 if (uevent->exclusion) {
333 tmp[i].exclusion = 1;
334 }
335 i++;
336 }
337
338 ret = nb_event;
339 *events = tmp;
340
341 error:
342 rcu_read_unlock();
343 return ret;
344 }
345
346 /*
347 * Fill lttng_event array of all kernel events in the channel.
348 */
349 static int list_lttng_kernel_events(char *channel_name,
350 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
351 {
352 int i = 0, ret;
353 unsigned int nb_event;
354 struct ltt_kernel_event *event;
355 struct ltt_kernel_channel *kchan;
356
357 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
358 if (kchan == NULL) {
359 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
360 goto error;
361 }
362
363 nb_event = kchan->event_count;
364
365 DBG("Listing events for channel %s", kchan->channel->name);
366
367 if (nb_event == 0) {
368 *events = NULL;
369 goto syscall;
370 }
371
372 *events = zmalloc(nb_event * sizeof(struct lttng_event));
373 if (*events == NULL) {
374 ret = LTTNG_ERR_FATAL;
375 goto error;
376 }
377
378 /* Kernel channels */
379 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
380 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
381 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
382 (*events)[i].enabled = event->enabled;
383
384 switch (event->event->instrumentation) {
385 case LTTNG_KERNEL_TRACEPOINT:
386 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
387 break;
388 case LTTNG_KERNEL_KRETPROBE:
389 (*events)[i].type = LTTNG_EVENT_FUNCTION;
390 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
391 sizeof(struct lttng_kernel_kprobe));
392 break;
393 case LTTNG_KERNEL_KPROBE:
394 (*events)[i].type = LTTNG_EVENT_PROBE;
395 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
396 sizeof(struct lttng_kernel_kprobe));
397 break;
398 case LTTNG_KERNEL_FUNCTION:
399 (*events)[i].type = LTTNG_EVENT_FUNCTION;
400 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
401 sizeof(struct lttng_kernel_function));
402 break;
403 case LTTNG_KERNEL_NOOP:
404 (*events)[i].type = LTTNG_EVENT_NOOP;
405 break;
406 case LTTNG_KERNEL_SYSCALL:
407 (*events)[i].type = LTTNG_EVENT_SYSCALL;
408 break;
409 case LTTNG_KERNEL_ALL:
410 assert(0);
411 break;
412 }
413 i++;
414 }
415
416 syscall:
417 if (syscall_table) {
418 ssize_t new_size;
419
420 new_size = syscall_list_channel(kchan, events, nb_event);
421 if (new_size < 0) {
422 free(events);
423 ret = -new_size;
424 goto error;
425 }
426 nb_event = new_size;
427 }
428
429 return nb_event;
430
431 error:
432 /* Negate the error code to differentiate the size from an error */
433 return -ret;
434 }
435
436 /*
437 * Add URI so the consumer output object. Set the correct path depending on the
438 * domain adding the default trace directory.
439 */
440 static int add_uri_to_consumer(struct consumer_output *consumer,
441 struct lttng_uri *uri, int domain, const char *session_name)
442 {
443 int ret = LTTNG_OK;
444 const char *default_trace_dir;
445
446 assert(uri);
447
448 if (consumer == NULL) {
449 DBG("No consumer detected. Don't add URI. Stopping.");
450 ret = LTTNG_ERR_NO_CONSUMER;
451 goto error;
452 }
453
454 switch (domain) {
455 case LTTNG_DOMAIN_KERNEL:
456 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
457 break;
458 case LTTNG_DOMAIN_UST:
459 default_trace_dir = DEFAULT_UST_TRACE_DIR;
460 break;
461 default:
462 /*
463 * This case is possible is we try to add the URI to the global tracing
464 * session consumer object which in this case there is no subdir.
465 */
466 default_trace_dir = "";
467 }
468
469 switch (uri->dtype) {
470 case LTTNG_DST_IPV4:
471 case LTTNG_DST_IPV6:
472 DBG2("Setting network URI to consumer");
473
474 if (consumer->type == CONSUMER_DST_NET) {
475 if ((uri->stype == LTTNG_STREAM_CONTROL &&
476 consumer->dst.net.control_isset) ||
477 (uri->stype == LTTNG_STREAM_DATA &&
478 consumer->dst.net.data_isset)) {
479 ret = LTTNG_ERR_URL_EXIST;
480 goto error;
481 }
482 } else {
483 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
484 }
485
486 consumer->type = CONSUMER_DST_NET;
487
488 /* Set URI into consumer output object */
489 ret = consumer_set_network_uri(consumer, uri);
490 if (ret < 0) {
491 ret = -ret;
492 goto error;
493 } else if (ret == 1) {
494 /*
495 * URI was the same in the consumer so we do not append the subdir
496 * again so to not duplicate output dir.
497 */
498 ret = LTTNG_OK;
499 goto error;
500 }
501
502 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
503 ret = consumer_set_subdir(consumer, session_name);
504 if (ret < 0) {
505 ret = LTTNG_ERR_FATAL;
506 goto error;
507 }
508 }
509
510 if (uri->stype == LTTNG_STREAM_CONTROL) {
511 /* On a new subdir, reappend the default trace dir. */
512 strncat(consumer->subdir, default_trace_dir,
513 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
514 DBG3("Append domain trace name to subdir %s", consumer->subdir);
515 }
516
517 break;
518 case LTTNG_DST_PATH:
519 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
520 memset(consumer->dst.trace_path, 0,
521 sizeof(consumer->dst.trace_path));
522 strncpy(consumer->dst.trace_path, uri->dst.path,
523 sizeof(consumer->dst.trace_path));
524 /* Append default trace dir */
525 strncat(consumer->dst.trace_path, default_trace_dir,
526 sizeof(consumer->dst.trace_path) -
527 strlen(consumer->dst.trace_path) - 1);
528 /* Flag consumer as local. */
529 consumer->type = CONSUMER_DST_LOCAL;
530 break;
531 }
532
533 ret = LTTNG_OK;
534
535 error:
536 return ret;
537 }
538
539 /*
540 * Init tracing by creating trace directory and sending fds kernel consumer.
541 */
542 static int init_kernel_tracing(struct ltt_kernel_session *session)
543 {
544 int ret = 0;
545 struct lttng_ht_iter iter;
546 struct consumer_socket *socket;
547
548 assert(session);
549
550 rcu_read_lock();
551
552 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
553 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
554 socket, node.node) {
555 pthread_mutex_lock(socket->lock);
556 ret = kernel_consumer_send_session(socket, session);
557 pthread_mutex_unlock(socket->lock);
558 if (ret < 0) {
559 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
560 goto error;
561 }
562 }
563 }
564
565 error:
566 rcu_read_unlock();
567 return ret;
568 }
569
570 /*
571 * Create a socket to the relayd using the URI.
572 *
573 * On success, the relayd_sock pointer is set to the created socket.
574 * Else, it's stays untouched and a lttcomm error code is returned.
575 */
576 static int create_connect_relayd(struct lttng_uri *uri,
577 struct lttcomm_relayd_sock **relayd_sock)
578 {
579 int ret;
580 struct lttcomm_relayd_sock *rsock;
581
582 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
583 RELAYD_VERSION_COMM_MINOR);
584 if (!rsock) {
585 ret = LTTNG_ERR_FATAL;
586 goto error;
587 }
588
589 /*
590 * Connect to relayd so we can proceed with a session creation. This call
591 * can possibly block for an arbitrary amount of time to set the health
592 * state to be in poll execution.
593 */
594 health_poll_entry();
595 ret = relayd_connect(rsock);
596 health_poll_exit();
597 if (ret < 0) {
598 ERR("Unable to reach lttng-relayd");
599 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
600 goto free_sock;
601 }
602
603 /* Create socket for control stream. */
604 if (uri->stype == LTTNG_STREAM_CONTROL) {
605 DBG3("Creating relayd stream socket from URI");
606
607 /* Check relayd version */
608 ret = relayd_version_check(rsock);
609 if (ret < 0) {
610 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
611 goto close_sock;
612 }
613 } else if (uri->stype == LTTNG_STREAM_DATA) {
614 DBG3("Creating relayd data socket from URI");
615 } else {
616 /* Command is not valid */
617 ERR("Relayd invalid stream type: %d", uri->stype);
618 ret = LTTNG_ERR_INVALID;
619 goto close_sock;
620 }
621
622 *relayd_sock = rsock;
623
624 return LTTNG_OK;
625
626 close_sock:
627 /* The returned value is not useful since we are on an error path. */
628 (void) relayd_close(rsock);
629 free_sock:
630 free(rsock);
631 error:
632 return ret;
633 }
634
635 /*
636 * Connect to the relayd using URI and send the socket to the right consumer.
637 */
638 static int send_consumer_relayd_socket(int domain, unsigned int session_id,
639 struct lttng_uri *relayd_uri, struct consumer_output *consumer,
640 struct consumer_socket *consumer_sock,
641 char *session_name, char *hostname, int session_live_timer)
642 {
643 int ret;
644 struct lttcomm_relayd_sock *rsock = NULL;
645
646 /* Connect to relayd and make version check if uri is the control. */
647 ret = create_connect_relayd(relayd_uri, &rsock);
648 if (ret != LTTNG_OK) {
649 goto error;
650 }
651 assert(rsock);
652
653 /* Set the network sequence index if not set. */
654 if (consumer->net_seq_index == (uint64_t) -1ULL) {
655 pthread_mutex_lock(&relayd_net_seq_idx_lock);
656 /*
657 * Increment net_seq_idx because we are about to transfer the
658 * new relayd socket to the consumer.
659 * Assign unique key so the consumer can match streams.
660 */
661 consumer->net_seq_index = ++relayd_net_seq_idx;
662 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
663 }
664
665 /* Send relayd socket to consumer. */
666 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
667 relayd_uri->stype, session_id,
668 session_name, hostname, session_live_timer);
669 if (ret < 0) {
670 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
671 goto close_sock;
672 }
673
674 /* Flag that the corresponding socket was sent. */
675 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
676 consumer_sock->control_sock_sent = 1;
677 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
678 consumer_sock->data_sock_sent = 1;
679 }
680
681 ret = LTTNG_OK;
682
683 /*
684 * Close socket which was dup on the consumer side. The session daemon does
685 * NOT keep track of the relayd socket(s) once transfer to the consumer.
686 */
687
688 close_sock:
689 (void) relayd_close(rsock);
690 free(rsock);
691
692 error:
693 if (ret != LTTNG_OK) {
694 /*
695 * The consumer output for this session should not be used anymore
696 * since the relayd connection failed thus making any tracing or/and
697 * streaming not usable.
698 */
699 consumer->enabled = 0;
700 }
701 return ret;
702 }
703
704 /*
705 * Send both relayd sockets to a specific consumer and domain. This is a
706 * helper function to facilitate sending the information to the consumer for a
707 * session.
708 */
709 static int send_consumer_relayd_sockets(int domain, unsigned int session_id,
710 struct consumer_output *consumer, struct consumer_socket *sock,
711 char *session_name, char *hostname, int session_live_timer)
712 {
713 int ret = LTTNG_OK;
714
715 assert(consumer);
716 assert(sock);
717
718 /* Sending control relayd socket. */
719 if (!sock->control_sock_sent) {
720 ret = send_consumer_relayd_socket(domain, session_id,
721 &consumer->dst.net.control, consumer, sock,
722 session_name, hostname, session_live_timer);
723 if (ret != LTTNG_OK) {
724 goto error;
725 }
726 }
727
728 /* Sending data relayd socket. */
729 if (!sock->data_sock_sent) {
730 ret = send_consumer_relayd_socket(domain, session_id,
731 &consumer->dst.net.data, consumer, sock,
732 session_name, hostname, session_live_timer);
733 if (ret != LTTNG_OK) {
734 goto error;
735 }
736 }
737
738 error:
739 return ret;
740 }
741
742 /*
743 * Setup relayd connections for a tracing session. First creates the socket to
744 * the relayd and send them to the right domain consumer. Consumer type MUST be
745 * network.
746 */
747 int cmd_setup_relayd(struct ltt_session *session)
748 {
749 int ret = LTTNG_OK;
750 struct ltt_ust_session *usess;
751 struct ltt_kernel_session *ksess;
752 struct consumer_socket *socket;
753 struct lttng_ht_iter iter;
754
755 assert(session);
756
757 usess = session->ust_session;
758 ksess = session->kernel_session;
759
760 DBG("Setting relayd for session %s", session->name);
761
762 rcu_read_lock();
763
764 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
765 && usess->consumer->enabled) {
766 /* For each consumer socket, send relayd sockets */
767 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
768 socket, node.node) {
769 pthread_mutex_lock(socket->lock);
770 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
771 usess->consumer, socket,
772 session->name, session->hostname,
773 session->live_timer);
774 pthread_mutex_unlock(socket->lock);
775 if (ret != LTTNG_OK) {
776 goto error;
777 }
778 /* Session is now ready for network streaming. */
779 session->net_handle = 1;
780 }
781 }
782
783 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
784 && ksess->consumer->enabled) {
785 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
786 socket, node.node) {
787 pthread_mutex_lock(socket->lock);
788 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
789 ksess->consumer, socket,
790 session->name, session->hostname,
791 session->live_timer);
792 pthread_mutex_unlock(socket->lock);
793 if (ret != LTTNG_OK) {
794 goto error;
795 }
796 /* Session is now ready for network streaming. */
797 session->net_handle = 1;
798 }
799 }
800
801 error:
802 rcu_read_unlock();
803 return ret;
804 }
805
806 /*
807 * Start a kernel session by opening all necessary streams.
808 */
809 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
810 {
811 int ret;
812 struct ltt_kernel_channel *kchan;
813
814 /* Open kernel metadata */
815 if (ksess->metadata == NULL && ksess->output_traces) {
816 ret = kernel_open_metadata(ksess);
817 if (ret < 0) {
818 ret = LTTNG_ERR_KERN_META_FAIL;
819 goto error;
820 }
821 }
822
823 /* Open kernel metadata stream */
824 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
825 ret = kernel_open_metadata_stream(ksess);
826 if (ret < 0) {
827 ERR("Kernel create metadata stream failed");
828 ret = LTTNG_ERR_KERN_STREAM_FAIL;
829 goto error;
830 }
831 }
832
833 /* For each channel */
834 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
835 if (kchan->stream_count == 0) {
836 ret = kernel_open_channel_stream(kchan);
837 if (ret < 0) {
838 ret = LTTNG_ERR_KERN_STREAM_FAIL;
839 goto error;
840 }
841 /* Update the stream global counter */
842 ksess->stream_count_global += ret;
843 }
844 }
845
846 /* Setup kernel consumer socket and send fds to it */
847 ret = init_kernel_tracing(ksess);
848 if (ret != 0) {
849 ret = LTTNG_ERR_KERN_START_FAIL;
850 goto error;
851 }
852
853 /* This start the kernel tracing */
854 ret = kernel_start_session(ksess);
855 if (ret < 0) {
856 ret = LTTNG_ERR_KERN_START_FAIL;
857 goto error;
858 }
859
860 /* Quiescent wait after starting trace */
861 kernel_wait_quiescent(kernel_tracer_fd);
862
863 ksess->active = 1;
864
865 ret = LTTNG_OK;
866
867 error:
868 return ret;
869 }
870
871 /*
872 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
873 */
874 int cmd_disable_channel(struct ltt_session *session, int domain,
875 char *channel_name)
876 {
877 int ret;
878 struct ltt_ust_session *usess;
879
880 usess = session->ust_session;
881
882 rcu_read_lock();
883
884 switch (domain) {
885 case LTTNG_DOMAIN_KERNEL:
886 {
887 ret = channel_kernel_disable(session->kernel_session,
888 channel_name);
889 if (ret != LTTNG_OK) {
890 goto error;
891 }
892
893 kernel_wait_quiescent(kernel_tracer_fd);
894 break;
895 }
896 case LTTNG_DOMAIN_UST:
897 {
898 struct ltt_ust_channel *uchan;
899 struct lttng_ht *chan_ht;
900
901 chan_ht = usess->domain_global.channels;
902
903 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
904 if (uchan == NULL) {
905 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
906 goto error;
907 }
908
909 ret = channel_ust_disable(usess, uchan);
910 if (ret != LTTNG_OK) {
911 goto error;
912 }
913 break;
914 }
915 default:
916 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
917 goto error;
918 }
919
920 ret = LTTNG_OK;
921
922 error:
923 rcu_read_unlock();
924 return ret;
925 }
926
927 /*
928 * Command LTTNG_TRACK_PID processed by the client thread.
929 *
930 * Called with session lock held.
931 */
932 int cmd_track_pid(struct ltt_session *session, int domain, int pid)
933 {
934 int ret;
935
936 rcu_read_lock();
937
938 switch (domain) {
939 case LTTNG_DOMAIN_KERNEL:
940 {
941 struct ltt_kernel_session *ksess;
942
943 ksess = session->kernel_session;
944
945 ret = kernel_track_pid(ksess, pid);
946 if (ret != LTTNG_OK) {
947 goto error;
948 }
949
950 kernel_wait_quiescent(kernel_tracer_fd);
951 break;
952 }
953 case LTTNG_DOMAIN_UST:
954 {
955 struct ltt_ust_session *usess;
956
957 usess = session->ust_session;
958
959 ret = trace_ust_track_pid(usess, pid);
960 if (ret != LTTNG_OK) {
961 goto error;
962 }
963 break;
964 }
965 default:
966 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
967 goto error;
968 }
969
970 ret = LTTNG_OK;
971
972 error:
973 rcu_read_unlock();
974 return ret;
975 }
976
977 /*
978 * Command LTTNG_UNTRACK_PID processed by the client thread.
979 *
980 * Called with session lock held.
981 */
982 int cmd_untrack_pid(struct ltt_session *session, int domain, int pid)
983 {
984 int ret;
985
986 rcu_read_lock();
987
988 switch (domain) {
989 case LTTNG_DOMAIN_KERNEL:
990 {
991 struct ltt_kernel_session *ksess;
992
993 ksess = session->kernel_session;
994
995 ret = kernel_untrack_pid(ksess, pid);
996 if (ret != LTTNG_OK) {
997 goto error;
998 }
999
1000 kernel_wait_quiescent(kernel_tracer_fd);
1001 break;
1002 }
1003 case LTTNG_DOMAIN_UST:
1004 {
1005 struct ltt_ust_session *usess;
1006
1007 usess = session->ust_session;
1008
1009 ret = trace_ust_untrack_pid(usess, pid);
1010 if (ret != LTTNG_OK) {
1011 goto error;
1012 }
1013 break;
1014 }
1015 default:
1016 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1017 goto error;
1018 }
1019
1020 ret = LTTNG_OK;
1021
1022 error:
1023 rcu_read_unlock();
1024 return ret;
1025 }
1026
1027 /*
1028 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1029 *
1030 * The wpipe arguments is used as a notifier for the kernel thread.
1031 */
1032 int cmd_enable_channel(struct ltt_session *session,
1033 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1034 {
1035 int ret;
1036 struct ltt_ust_session *usess = session->ust_session;
1037 struct lttng_ht *chan_ht;
1038 size_t len;
1039
1040 assert(session);
1041 assert(attr);
1042 assert(domain);
1043
1044 len = strnlen(attr->name, sizeof(attr->name));
1045
1046 /* Validate channel name */
1047 if (attr->name[0] == '.' ||
1048 memchr(attr->name, '/', len) != NULL) {
1049 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1050 goto end;
1051 }
1052
1053 DBG("Enabling channel %s for session %s", attr->name, session->name);
1054
1055 rcu_read_lock();
1056
1057 /*
1058 * Don't try to enable a channel if the session has been started at
1059 * some point in time before. The tracer does not allow it.
1060 */
1061 if (session->has_been_started) {
1062 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1063 goto error;
1064 }
1065
1066 /*
1067 * If the session is a live session, remove the switch timer, the
1068 * live timer does the same thing but sends also synchronisation
1069 * beacons for inactive streams.
1070 */
1071 if (session->live_timer > 0) {
1072 attr->attr.live_timer_interval = session->live_timer;
1073 attr->attr.switch_timer_interval = 0;
1074 }
1075
1076 /*
1077 * The ringbuffer (both in user space and kernel) behave badly in overwrite
1078 * mode and with less than 2 subbuf so block it right away and send back an
1079 * invalid attribute error.
1080 */
1081 if (attr->attr.overwrite && attr->attr.num_subbuf < 2) {
1082 ret = LTTNG_ERR_INVALID;
1083 goto error;
1084 }
1085
1086 switch (domain->type) {
1087 case LTTNG_DOMAIN_KERNEL:
1088 {
1089 struct ltt_kernel_channel *kchan;
1090
1091 kchan = trace_kernel_get_channel_by_name(attr->name,
1092 session->kernel_session);
1093 if (kchan == NULL) {
1094 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1095 if (attr->name[0] != '\0') {
1096 session->kernel_session->has_non_default_channel = 1;
1097 }
1098 } else {
1099 ret = channel_kernel_enable(session->kernel_session, kchan);
1100 }
1101
1102 if (ret != LTTNG_OK) {
1103 goto error;
1104 }
1105
1106 kernel_wait_quiescent(kernel_tracer_fd);
1107 break;
1108 }
1109 case LTTNG_DOMAIN_UST:
1110 {
1111 struct ltt_ust_channel *uchan;
1112
1113 chan_ht = usess->domain_global.channels;
1114
1115 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1116 if (uchan == NULL) {
1117 ret = channel_ust_create(usess, attr, domain->buf_type);
1118 if (attr->name[0] != '\0') {
1119 usess->has_non_default_channel = 1;
1120 }
1121 } else {
1122 ret = channel_ust_enable(usess, uchan);
1123 }
1124 break;
1125 }
1126 default:
1127 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1128 goto error;
1129 }
1130
1131 error:
1132 rcu_read_unlock();
1133 end:
1134 return ret;
1135 }
1136
1137 /*
1138 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1139 */
1140 int cmd_disable_event(struct ltt_session *session, int domain,
1141 char *channel_name,
1142 struct lttng_event *event)
1143 {
1144 int ret;
1145 char *event_name;
1146
1147 DBG("Disable event command for event \'%s\'", event->name);
1148
1149 event_name = event->name;
1150 if (validate_event_name(event_name)) {
1151 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1152 goto error;
1153 }
1154
1155 /* Error out on unhandled search criteria */
1156 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1157 || event->pid || event->filter || event->exclusion) {
1158 ret = LTTNG_ERR_UNK;
1159 goto error;
1160 }
1161
1162 rcu_read_lock();
1163
1164 switch (domain) {
1165 case LTTNG_DOMAIN_KERNEL:
1166 {
1167 struct ltt_kernel_channel *kchan;
1168 struct ltt_kernel_session *ksess;
1169
1170 ksess = session->kernel_session;
1171
1172 /*
1173 * If a non-default channel has been created in the
1174 * session, explicitely require that -c chan_name needs
1175 * to be provided.
1176 */
1177 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1178 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1179 goto error_unlock;
1180 }
1181
1182 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1183 if (kchan == NULL) {
1184 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1185 goto error_unlock;
1186 }
1187
1188 switch (event->type) {
1189 case LTTNG_EVENT_ALL:
1190 ret = event_kernel_disable_event_all(kchan);
1191 if (ret != LTTNG_OK) {
1192 goto error_unlock;
1193 }
1194 break;
1195 case LTTNG_EVENT_TRACEPOINT: /* fall-through */
1196 case LTTNG_EVENT_SYSCALL:
1197 if (!strcmp(event_name, "*")) {
1198 ret = event_kernel_disable_event_type(kchan,
1199 event->type);
1200 } else {
1201 ret = event_kernel_disable_event(kchan,
1202 event_name);
1203 }
1204 if (ret != LTTNG_OK) {
1205 goto error_unlock;
1206 }
1207 break;
1208 case LTTNG_EVENT_PROBE:
1209 case LTTNG_EVENT_FUNCTION:
1210 case LTTNG_EVENT_FUNCTION_ENTRY:
1211 ret = event_kernel_disable_event(kchan, event_name);
1212 if (ret != LTTNG_OK) {
1213 goto error_unlock;
1214 }
1215 break;
1216 default:
1217 ret = LTTNG_ERR_UNK;
1218 goto error_unlock;
1219 }
1220
1221 kernel_wait_quiescent(kernel_tracer_fd);
1222 break;
1223 }
1224 case LTTNG_DOMAIN_UST:
1225 {
1226 struct ltt_ust_channel *uchan;
1227 struct ltt_ust_session *usess;
1228
1229 usess = session->ust_session;
1230
1231 if (validate_ust_event_name(event_name)) {
1232 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1233 goto error_unlock;
1234 }
1235
1236 /*
1237 * If a non-default channel has been created in the
1238 * session, explicitely require that -c chan_name needs
1239 * to be provided.
1240 */
1241 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1242 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1243 goto error_unlock;
1244 }
1245
1246 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1247 channel_name);
1248 if (uchan == NULL) {
1249 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1250 goto error_unlock;
1251 }
1252
1253 switch (event->type) {
1254 case LTTNG_EVENT_ALL:
1255 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
1256 if (ret != LTTNG_OK) {
1257 goto error_unlock;
1258 }
1259 break;
1260 default:
1261 ret = LTTNG_ERR_UNK;
1262 goto error_unlock;
1263 }
1264
1265 DBG3("Disable UST event %s in channel %s completed", event_name,
1266 channel_name);
1267 break;
1268 }
1269 case LTTNG_DOMAIN_LOG4J:
1270 case LTTNG_DOMAIN_JUL:
1271 case LTTNG_DOMAIN_PYTHON:
1272 {
1273 struct agent *agt;
1274 struct ltt_ust_session *usess = session->ust_session;
1275
1276 assert(usess);
1277
1278 switch (event->type) {
1279 case LTTNG_EVENT_ALL:
1280 break;
1281 default:
1282 ret = LTTNG_ERR_UNK;
1283 goto error_unlock;
1284 }
1285
1286 agt = trace_ust_find_agent(usess, domain);
1287 if (!agt) {
1288 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1289 goto error_unlock;
1290 }
1291 /* The wild card * means that everything should be disabled. */
1292 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1293 ret = event_agent_disable_all(usess, agt);
1294 } else {
1295 ret = event_agent_disable(usess, agt, event_name);
1296 }
1297 if (ret != LTTNG_OK) {
1298 goto error_unlock;
1299 }
1300
1301 break;
1302 }
1303 default:
1304 ret = LTTNG_ERR_UND;
1305 goto error_unlock;
1306 }
1307
1308 ret = LTTNG_OK;
1309
1310 error_unlock:
1311 rcu_read_unlock();
1312 error:
1313 return ret;
1314 }
1315
1316 /*
1317 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1318 */
1319 int cmd_add_context(struct ltt_session *session, int domain,
1320 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1321 {
1322 int ret, chan_kern_created = 0, chan_ust_created = 0;
1323
1324 switch (domain) {
1325 case LTTNG_DOMAIN_KERNEL:
1326 assert(session->kernel_session);
1327
1328 if (session->kernel_session->channel_count == 0) {
1329 /* Create default channel */
1330 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1331 if (ret != LTTNG_OK) {
1332 goto error;
1333 }
1334 chan_kern_created = 1;
1335 }
1336 /* Add kernel context to kernel tracer */
1337 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1338 if (ret != LTTNG_OK) {
1339 goto error;
1340 }
1341 break;
1342 case LTTNG_DOMAIN_UST:
1343 {
1344 struct ltt_ust_session *usess = session->ust_session;
1345 unsigned int chan_count;
1346
1347 assert(usess);
1348
1349 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1350 if (chan_count == 0) {
1351 struct lttng_channel *attr;
1352 /* Create default channel */
1353 attr = channel_new_default_attr(domain, usess->buffer_type);
1354 if (attr == NULL) {
1355 ret = LTTNG_ERR_FATAL;
1356 goto error;
1357 }
1358
1359 ret = channel_ust_create(usess, attr, usess->buffer_type);
1360 if (ret != LTTNG_OK) {
1361 free(attr);
1362 goto error;
1363 }
1364 free(attr);
1365 chan_ust_created = 1;
1366 }
1367
1368 ret = context_ust_add(usess, domain, ctx, channel_name);
1369 if (ret != LTTNG_OK) {
1370 goto error;
1371 }
1372 break;
1373 }
1374 default:
1375 ret = LTTNG_ERR_UND;
1376 goto error;
1377 }
1378
1379 return LTTNG_OK;
1380
1381 error:
1382 if (chan_kern_created) {
1383 struct ltt_kernel_channel *kchan =
1384 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1385 session->kernel_session);
1386 /* Created previously, this should NOT fail. */
1387 assert(kchan);
1388 kernel_destroy_channel(kchan);
1389 }
1390
1391 if (chan_ust_created) {
1392 struct ltt_ust_channel *uchan =
1393 trace_ust_find_channel_by_name(
1394 session->ust_session->domain_global.channels,
1395 DEFAULT_CHANNEL_NAME);
1396 /* Created previously, this should NOT fail. */
1397 assert(uchan);
1398 /* Remove from the channel list of the session. */
1399 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1400 uchan);
1401 trace_ust_destroy_channel(uchan);
1402 }
1403 return ret;
1404 }
1405
1406 static int validate_event_name(const char *name)
1407 {
1408 int ret = 0;
1409 const char *c = name;
1410 const char *event_name_end = c + LTTNG_SYMBOL_NAME_LEN;
1411 bool null_terminated = false;
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 null_terminated = true;
1421 goto end;
1422 case '\\':
1423 c++;
1424 break;
1425 case '*':
1426 if ((c + 1) < event_name_end && *(c + 1)) {
1427 /* Wildcard is not the last character */
1428 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1429 goto end;
1430 }
1431 default:
1432 break;
1433 }
1434 c++;
1435 }
1436 end:
1437 if (!ret && !null_terminated) {
1438 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1439 }
1440 return ret;
1441 }
1442
1443 static inline bool name_starts_with(const char *name, const char *prefix)
1444 {
1445 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1446
1447 return !strncmp(name, prefix, max_cmp_len);
1448 }
1449
1450 /* Perform userspace-specific event name validation */
1451 static int validate_ust_event_name(const char *name)
1452 {
1453 int ret = 0;
1454
1455 if (!name) {
1456 ret = -1;
1457 goto end;
1458 }
1459
1460 /*
1461 * Check name against all internal UST event component namespaces used
1462 * by the agents.
1463 */
1464 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1465 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1466 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1467 ret = -1;
1468 }
1469
1470 end:
1471 return ret;
1472 }
1473
1474 /*
1475 * Internal version of cmd_enable_event() with a supplemental
1476 * "internal_event" flag which is used to enable internal events which should
1477 * be hidden from clients. Such events are used in the agent implementation to
1478 * enable the events through which all "agent" events are funeled.
1479 */
1480 static int _cmd_enable_event(struct ltt_session *session,
1481 struct lttng_domain *domain,
1482 char *channel_name, struct lttng_event *event,
1483 char *filter_expression,
1484 struct lttng_filter_bytecode *filter,
1485 struct lttng_event_exclusion *exclusion,
1486 int wpipe, bool internal_event)
1487 {
1488 int ret, channel_created = 0;
1489 struct lttng_channel *attr;
1490
1491 assert(session);
1492 assert(event);
1493 assert(channel_name);
1494
1495 DBG("Enable event command for event \'%s\'", event->name);
1496
1497 ret = validate_event_name(event->name);
1498 if (ret) {
1499 goto error;
1500 }
1501
1502 rcu_read_lock();
1503
1504 switch (domain->type) {
1505 case LTTNG_DOMAIN_KERNEL:
1506 {
1507 struct ltt_kernel_channel *kchan;
1508
1509 /*
1510 * If a non-default channel has been created in the
1511 * session, explicitely require that -c chan_name needs
1512 * to be provided.
1513 */
1514 if (session->kernel_session->has_non_default_channel
1515 && channel_name[0] == '\0') {
1516 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1517 goto error;
1518 }
1519
1520 kchan = trace_kernel_get_channel_by_name(channel_name,
1521 session->kernel_session);
1522 if (kchan == NULL) {
1523 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1524 LTTNG_BUFFER_GLOBAL);
1525 if (attr == NULL) {
1526 ret = LTTNG_ERR_FATAL;
1527 goto error;
1528 }
1529 strncpy(attr->name, channel_name, sizeof(attr->name));
1530
1531 ret = cmd_enable_channel(session, domain, attr, wpipe);
1532 if (ret != LTTNG_OK) {
1533 free(attr);
1534 goto error;
1535 }
1536 free(attr);
1537
1538 channel_created = 1;
1539 }
1540
1541 /* Get the newly created kernel channel pointer */
1542 kchan = trace_kernel_get_channel_by_name(channel_name,
1543 session->kernel_session);
1544 if (kchan == NULL) {
1545 /* This sould not happen... */
1546 ret = LTTNG_ERR_FATAL;
1547 goto error;
1548 }
1549
1550 switch (event->type) {
1551 case LTTNG_EVENT_ALL:
1552 {
1553 char *filter_expression_a = NULL;
1554 struct lttng_filter_bytecode *filter_a = NULL;
1555
1556 /*
1557 * We need to duplicate filter_expression and filter,
1558 * because ownership is passed to first enable
1559 * event.
1560 */
1561 if (filter_expression) {
1562 filter_expression_a = strdup(filter_expression);
1563 if (!filter_expression_a) {
1564 ret = LTTNG_ERR_FATAL;
1565 goto error;
1566 }
1567 }
1568 if (filter) {
1569 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
1570 if (!filter_a) {
1571 free(filter_expression_a);
1572 ret = LTTNG_ERR_FATAL;
1573 goto error;
1574 }
1575 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
1576 }
1577 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
1578 ret = event_kernel_enable_event(kchan, event,
1579 filter_expression, filter);
1580 /* We have passed ownership */
1581 filter_expression = NULL;
1582 filter = NULL;
1583 if (ret != LTTNG_OK) {
1584 if (channel_created) {
1585 /* Let's not leak a useless channel. */
1586 kernel_destroy_channel(kchan);
1587 }
1588 free(filter_expression_a);
1589 free(filter_a);
1590 goto error;
1591 }
1592 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
1593 ret = event_kernel_enable_event(kchan, event,
1594 filter_expression_a, filter_a);
1595 if (ret != LTTNG_OK) {
1596 free(filter_expression_a);
1597 free(filter_a);
1598 goto error;
1599 }
1600 break;
1601 }
1602 case LTTNG_EVENT_PROBE:
1603 case LTTNG_EVENT_FUNCTION:
1604 case LTTNG_EVENT_FUNCTION_ENTRY:
1605 case LTTNG_EVENT_TRACEPOINT:
1606 ret = event_kernel_enable_event(kchan, event,
1607 filter_expression, filter);
1608 /* We have passed ownership */
1609 filter_expression = NULL;
1610 filter = NULL;
1611 if (ret != LTTNG_OK) {
1612 if (channel_created) {
1613 /* Let's not leak a useless channel. */
1614 kernel_destroy_channel(kchan);
1615 }
1616 goto error;
1617 }
1618 break;
1619 case LTTNG_EVENT_SYSCALL:
1620 ret = event_kernel_enable_event(kchan, event,
1621 filter_expression, filter);
1622 /* We have passed ownership */
1623 filter_expression = NULL;
1624 filter = NULL;
1625 if (ret != LTTNG_OK) {
1626 goto error;
1627 }
1628 break;
1629 default:
1630 ret = LTTNG_ERR_UNK;
1631 goto error;
1632 }
1633
1634 kernel_wait_quiescent(kernel_tracer_fd);
1635 break;
1636 }
1637 case LTTNG_DOMAIN_UST:
1638 {
1639 struct ltt_ust_channel *uchan;
1640 struct ltt_ust_session *usess = session->ust_session;
1641
1642 assert(usess);
1643
1644 /*
1645 * If a non-default channel has been created in the
1646 * session, explicitely require that -c chan_name needs
1647 * to be provided.
1648 */
1649 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1650 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1651 goto error;
1652 }
1653
1654 /* Get channel from global UST domain */
1655 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1656 channel_name);
1657 if (uchan == NULL) {
1658 /* Create default channel */
1659 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1660 usess->buffer_type);
1661 if (attr == NULL) {
1662 ret = LTTNG_ERR_FATAL;
1663 goto error;
1664 }
1665 strncpy(attr->name, channel_name, sizeof(attr->name));
1666
1667 ret = cmd_enable_channel(session, domain, attr, wpipe);
1668 if (ret != LTTNG_OK) {
1669 free(attr);
1670 goto error;
1671 }
1672 free(attr);
1673
1674 /* Get the newly created channel reference back */
1675 uchan = trace_ust_find_channel_by_name(
1676 usess->domain_global.channels, channel_name);
1677 assert(uchan);
1678 }
1679
1680 if (!internal_event) {
1681 /*
1682 * Ensure the event name is not reserved for internal
1683 * use.
1684 */
1685 ret = validate_ust_event_name(event->name);
1686 if (ret) {
1687 WARN("Userspace event name %s failed validation.",
1688 event->name ?
1689 event->name : "NULL");
1690 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1691 goto error;
1692 }
1693 }
1694
1695 /* At this point, the session and channel exist on the tracer */
1696 ret = event_ust_enable_tracepoint(usess, uchan, event,
1697 filter_expression, filter, exclusion,
1698 internal_event);
1699 /* We have passed ownership */
1700 filter_expression = NULL;
1701 filter = NULL;
1702 exclusion = NULL;
1703 if (ret != LTTNG_OK) {
1704 goto error;
1705 }
1706 break;
1707 }
1708 case LTTNG_DOMAIN_LOG4J:
1709 case LTTNG_DOMAIN_JUL:
1710 case LTTNG_DOMAIN_PYTHON:
1711 {
1712 const char *default_event_name, *default_chan_name;
1713 struct agent *agt;
1714 struct lttng_event uevent;
1715 struct lttng_domain tmp_dom;
1716 struct ltt_ust_session *usess = session->ust_session;
1717
1718 assert(usess);
1719
1720 agt = trace_ust_find_agent(usess, domain->type);
1721 if (!agt) {
1722 agt = agent_create(domain->type);
1723 if (!agt) {
1724 ret = -LTTNG_ERR_NOMEM;
1725 goto error;
1726 }
1727 agent_add(agt, usess->agents);
1728 }
1729
1730 /* Create the default tracepoint. */
1731 memset(&uevent, 0, sizeof(uevent));
1732 uevent.type = LTTNG_EVENT_TRACEPOINT;
1733 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
1734 default_event_name = event_get_default_agent_ust_name(domain->type);
1735 if (!default_event_name) {
1736 ret = -LTTNG_ERR_FATAL;
1737 goto error;
1738 }
1739 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
1740 uevent.name[sizeof(uevent.name) - 1] = '\0';
1741
1742 /*
1743 * The domain type is changed because we are about to enable the
1744 * default channel and event for the JUL domain that are hardcoded.
1745 * This happens in the UST domain.
1746 */
1747 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
1748 tmp_dom.type = LTTNG_DOMAIN_UST;
1749
1750 switch (domain->type) {
1751 case LTTNG_DOMAIN_LOG4J:
1752 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
1753 break;
1754 case LTTNG_DOMAIN_JUL:
1755 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
1756 break;
1757 case LTTNG_DOMAIN_PYTHON:
1758 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
1759 break;
1760 default:
1761 /* The switch/case we are in makes this impossible */
1762 assert(0);
1763 }
1764
1765 {
1766 struct lttng_filter_bytecode *filter_copy = NULL;
1767
1768 if (filter) {
1769 filter_copy = zmalloc(
1770 sizeof(struct lttng_filter_bytecode)
1771 + filter->len);
1772 if (!filter_copy) {
1773 goto error;
1774 }
1775
1776 memcpy(filter_copy, filter,
1777 sizeof(struct lttng_filter_bytecode)
1778 + filter->len);
1779 }
1780
1781 ret = cmd_enable_event_internal(session, &tmp_dom,
1782 (char *) default_chan_name,
1783 &uevent, filter_expression, filter_copy,
1784 NULL, wpipe);
1785 /* We have passed ownership */
1786 filter_expression = NULL;
1787 }
1788
1789 if (ret != LTTNG_OK && ret != LTTNG_ERR_UST_EVENT_ENABLED) {
1790 goto error;
1791 }
1792
1793 /* The wild card * means that everything should be enabled. */
1794 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1795 ret = event_agent_enable_all(usess, agt, event, filter);
1796 filter = NULL;
1797 } else {
1798 ret = event_agent_enable(usess, agt, event, filter);
1799 filter = NULL;
1800 }
1801 if (ret != LTTNG_OK) {
1802 goto error;
1803 }
1804
1805 break;
1806 }
1807 default:
1808 ret = LTTNG_ERR_UND;
1809 goto error;
1810 }
1811
1812 ret = LTTNG_OK;
1813
1814 error:
1815 free(filter_expression);
1816 free(filter);
1817 free(exclusion);
1818 rcu_read_unlock();
1819 return ret;
1820 }
1821
1822 /*
1823 * Command LTTNG_ENABLE_EVENT processed by the client thread.
1824 * We own filter, exclusion, and filter_expression.
1825 */
1826 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1827 char *channel_name, struct lttng_event *event,
1828 char *filter_expression,
1829 struct lttng_filter_bytecode *filter,
1830 struct lttng_event_exclusion *exclusion,
1831 int wpipe)
1832 {
1833 return _cmd_enable_event(session, domain, channel_name, event,
1834 filter_expression, filter, exclusion, wpipe, false);
1835 }
1836
1837 /*
1838 * Enable an event which is internal to LTTng. An internal should
1839 * never be made visible to clients and are immune to checks such as
1840 * reserved names.
1841 */
1842 static int cmd_enable_event_internal(struct ltt_session *session,
1843 struct lttng_domain *domain,
1844 char *channel_name, struct lttng_event *event,
1845 char *filter_expression,
1846 struct lttng_filter_bytecode *filter,
1847 struct lttng_event_exclusion *exclusion,
1848 int wpipe)
1849 {
1850 return _cmd_enable_event(session, domain, channel_name, event,
1851 filter_expression, filter, exclusion, wpipe, true);
1852 }
1853
1854 /*
1855 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1856 */
1857 ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
1858 {
1859 int ret;
1860 ssize_t nb_events = 0;
1861
1862 switch (domain) {
1863 case LTTNG_DOMAIN_KERNEL:
1864 nb_events = kernel_list_events(kernel_tracer_fd, events);
1865 if (nb_events < 0) {
1866 ret = LTTNG_ERR_KERN_LIST_FAIL;
1867 goto error;
1868 }
1869 break;
1870 case LTTNG_DOMAIN_UST:
1871 nb_events = ust_app_list_events(events);
1872 if (nb_events < 0) {
1873 ret = LTTNG_ERR_UST_LIST_FAIL;
1874 goto error;
1875 }
1876 break;
1877 case LTTNG_DOMAIN_LOG4J:
1878 case LTTNG_DOMAIN_JUL:
1879 case LTTNG_DOMAIN_PYTHON:
1880 nb_events = agent_list_events(events, domain);
1881 if (nb_events < 0) {
1882 ret = LTTNG_ERR_UST_LIST_FAIL;
1883 goto error;
1884 }
1885 break;
1886 default:
1887 ret = LTTNG_ERR_UND;
1888 goto error;
1889 }
1890
1891 return nb_events;
1892
1893 error:
1894 /* Return negative value to differentiate return code */
1895 return -ret;
1896 }
1897
1898 /*
1899 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1900 */
1901 ssize_t cmd_list_tracepoint_fields(int domain,
1902 struct lttng_event_field **fields)
1903 {
1904 int ret;
1905 ssize_t nb_fields = 0;
1906
1907 switch (domain) {
1908 case LTTNG_DOMAIN_UST:
1909 nb_fields = ust_app_list_event_fields(fields);
1910 if (nb_fields < 0) {
1911 ret = LTTNG_ERR_UST_LIST_FAIL;
1912 goto error;
1913 }
1914 break;
1915 case LTTNG_DOMAIN_KERNEL:
1916 default: /* fall-through */
1917 ret = LTTNG_ERR_UND;
1918 goto error;
1919 }
1920
1921 return nb_fields;
1922
1923 error:
1924 /* Return negative value to differentiate return code */
1925 return -ret;
1926 }
1927
1928 ssize_t cmd_list_syscalls(struct lttng_event **events)
1929 {
1930 return syscall_table_list(events);
1931 }
1932
1933 /*
1934 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
1935 *
1936 * Called with session lock held.
1937 */
1938 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
1939 int domain, int32_t **pids)
1940 {
1941 int ret;
1942 ssize_t nr_pids = 0;
1943
1944 switch (domain) {
1945 case LTTNG_DOMAIN_KERNEL:
1946 {
1947 struct ltt_kernel_session *ksess;
1948
1949 ksess = session->kernel_session;
1950 nr_pids = kernel_list_tracker_pids(ksess, pids);
1951 if (nr_pids < 0) {
1952 ret = LTTNG_ERR_KERN_LIST_FAIL;
1953 goto error;
1954 }
1955 break;
1956 }
1957 case LTTNG_DOMAIN_UST:
1958 {
1959 struct ltt_ust_session *usess;
1960
1961 usess = session->ust_session;
1962 nr_pids = trace_ust_list_tracker_pids(usess, pids);
1963 if (nr_pids < 0) {
1964 ret = LTTNG_ERR_UST_LIST_FAIL;
1965 goto error;
1966 }
1967 break;
1968 }
1969 case LTTNG_DOMAIN_LOG4J:
1970 case LTTNG_DOMAIN_JUL:
1971 case LTTNG_DOMAIN_PYTHON:
1972 default:
1973 ret = LTTNG_ERR_UND;
1974 goto error;
1975 }
1976
1977 return nr_pids;
1978
1979 error:
1980 /* Return negative value to differentiate return code */
1981 return -ret;
1982 }
1983
1984 /*
1985 * Command LTTNG_START_TRACE processed by the client thread.
1986 *
1987 * Called with session mutex held.
1988 */
1989 int cmd_start_trace(struct ltt_session *session)
1990 {
1991 int ret;
1992 unsigned long nb_chan = 0;
1993 struct ltt_kernel_session *ksession;
1994 struct ltt_ust_session *usess;
1995
1996 assert(session);
1997
1998 /* Ease our life a bit ;) */
1999 ksession = session->kernel_session;
2000 usess = session->ust_session;
2001
2002 /* Is the session already started? */
2003 if (session->active) {
2004 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2005 goto error;
2006 }
2007
2008 /*
2009 * Starting a session without channel is useless since after that it's not
2010 * possible to enable channel thus inform the client.
2011 */
2012 if (usess && usess->domain_global.channels) {
2013 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2014 }
2015 if (ksession) {
2016 nb_chan += ksession->channel_count;
2017 }
2018 if (!nb_chan) {
2019 ret = LTTNG_ERR_NO_CHANNEL;
2020 goto error;
2021 }
2022
2023 /* Kernel tracing */
2024 if (ksession != NULL) {
2025 ret = start_kernel_session(ksession, kernel_tracer_fd);
2026 if (ret != LTTNG_OK) {
2027 goto error;
2028 }
2029 }
2030
2031 /* Flag session that trace should start automatically */
2032 if (usess) {
2033 /*
2034 * Even though the start trace might fail, flag this session active so
2035 * other application coming in are started by default.
2036 */
2037 usess->active = 1;
2038
2039 ret = ust_app_start_trace_all(usess);
2040 if (ret < 0) {
2041 ret = LTTNG_ERR_UST_START_FAIL;
2042 goto error;
2043 }
2044 }
2045
2046 /* Flag this after a successful start. */
2047 session->has_been_started = 1;
2048 session->active = 1;
2049
2050 ret = LTTNG_OK;
2051
2052 error:
2053 return ret;
2054 }
2055
2056 /*
2057 * Command LTTNG_STOP_TRACE processed by the client thread.
2058 */
2059 int cmd_stop_trace(struct ltt_session *session)
2060 {
2061 int ret;
2062 struct ltt_kernel_channel *kchan;
2063 struct ltt_kernel_session *ksession;
2064 struct ltt_ust_session *usess;
2065
2066 assert(session);
2067
2068 /* Short cut */
2069 ksession = session->kernel_session;
2070 usess = session->ust_session;
2071
2072 /* Session is not active. Skip everythong and inform the client. */
2073 if (!session->active) {
2074 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2075 goto error;
2076 }
2077
2078 /* Kernel tracer */
2079 if (ksession && ksession->active) {
2080 DBG("Stop kernel tracing");
2081
2082 /* Flush metadata if exist */
2083 if (ksession->metadata_stream_fd >= 0) {
2084 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2085 if (ret < 0) {
2086 ERR("Kernel metadata flush failed");
2087 }
2088 }
2089
2090 /* Flush all buffers before stopping */
2091 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2092 ret = kernel_flush_buffer(kchan);
2093 if (ret < 0) {
2094 ERR("Kernel flush buffer error");
2095 }
2096 }
2097
2098 ret = kernel_stop_session(ksession);
2099 if (ret < 0) {
2100 ret = LTTNG_ERR_KERN_STOP_FAIL;
2101 goto error;
2102 }
2103
2104 kernel_wait_quiescent(kernel_tracer_fd);
2105
2106 ksession->active = 0;
2107 }
2108
2109 if (usess && usess->active) {
2110 /*
2111 * Even though the stop trace might fail, flag this session inactive so
2112 * other application coming in are not started by default.
2113 */
2114 usess->active = 0;
2115
2116 ret = ust_app_stop_trace_all(usess);
2117 if (ret < 0) {
2118 ret = LTTNG_ERR_UST_STOP_FAIL;
2119 goto error;
2120 }
2121 }
2122
2123 /* Flag inactive after a successful stop. */
2124 session->active = 0;
2125 ret = LTTNG_OK;
2126
2127 error:
2128 return ret;
2129 }
2130
2131 /*
2132 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2133 */
2134 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2135 struct lttng_uri *uris)
2136 {
2137 int ret, i;
2138 struct ltt_kernel_session *ksess = session->kernel_session;
2139 struct ltt_ust_session *usess = session->ust_session;
2140
2141 assert(session);
2142 assert(uris);
2143 assert(nb_uri > 0);
2144
2145 /* Can't set consumer URI if the session is active. */
2146 if (session->active) {
2147 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2148 goto error;
2149 }
2150
2151 /* Set the "global" consumer URIs */
2152 for (i = 0; i < nb_uri; i++) {
2153 ret = add_uri_to_consumer(session->consumer,
2154 &uris[i], 0, session->name);
2155 if (ret != LTTNG_OK) {
2156 goto error;
2157 }
2158 }
2159
2160 /* Set UST session URIs */
2161 if (session->ust_session) {
2162 for (i = 0; i < nb_uri; i++) {
2163 ret = add_uri_to_consumer(
2164 session->ust_session->consumer,
2165 &uris[i], LTTNG_DOMAIN_UST,
2166 session->name);
2167 if (ret != LTTNG_OK) {
2168 goto error;
2169 }
2170 }
2171 }
2172
2173 /* Set kernel session URIs */
2174 if (session->kernel_session) {
2175 for (i = 0; i < nb_uri; i++) {
2176 ret = add_uri_to_consumer(
2177 session->kernel_session->consumer,
2178 &uris[i], LTTNG_DOMAIN_KERNEL,
2179 session->name);
2180 if (ret != LTTNG_OK) {
2181 goto error;
2182 }
2183 }
2184 }
2185
2186 /*
2187 * Make sure to set the session in output mode after we set URI since a
2188 * session can be created without URL (thus flagged in no output mode).
2189 */
2190 session->output_traces = 1;
2191 if (ksess) {
2192 ksess->output_traces = 1;
2193 }
2194
2195 if (usess) {
2196 usess->output_traces = 1;
2197 }
2198
2199 /* All good! */
2200 ret = LTTNG_OK;
2201
2202 error:
2203 return ret;
2204 }
2205
2206 /*
2207 * Command LTTNG_CREATE_SESSION processed by the client thread.
2208 */
2209 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
2210 size_t nb_uri, lttng_sock_cred *creds, unsigned int live_timer)
2211 {
2212 int ret;
2213 struct ltt_session *session;
2214
2215 assert(name);
2216 assert(creds);
2217
2218 /*
2219 * Verify if the session already exist
2220 *
2221 * XXX: There is no need for the session lock list here since the caller
2222 * (process_client_msg) is holding it. We might want to change that so a
2223 * single command does not lock the entire session list.
2224 */
2225 session = session_find_by_name(name);
2226 if (session != NULL) {
2227 ret = LTTNG_ERR_EXIST_SESS;
2228 goto find_error;
2229 }
2230
2231 /* Create tracing session in the registry */
2232 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
2233 LTTNG_SOCK_GET_GID_CRED(creds));
2234 if (ret != LTTNG_OK) {
2235 goto session_error;
2236 }
2237
2238 /*
2239 * Get the newly created session pointer back
2240 *
2241 * XXX: There is no need for the session lock list here since the caller
2242 * (process_client_msg) is holding it. We might want to change that so a
2243 * single command does not lock the entire session list.
2244 */
2245 session = session_find_by_name(name);
2246 assert(session);
2247
2248 session->live_timer = live_timer;
2249 /* Create default consumer output for the session not yet created. */
2250 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
2251 if (session->consumer == NULL) {
2252 ret = LTTNG_ERR_FATAL;
2253 goto consumer_error;
2254 }
2255
2256 if (uris) {
2257 ret = cmd_set_consumer_uri(session, nb_uri, uris);
2258 if (ret != LTTNG_OK) {
2259 goto consumer_error;
2260 }
2261 session->output_traces = 1;
2262 } else {
2263 session->output_traces = 0;
2264 DBG2("Session %s created with no output", session->name);
2265 }
2266
2267 session->consumer->enabled = 1;
2268
2269 return LTTNG_OK;
2270
2271 consumer_error:
2272 session_destroy(session);
2273 session_error:
2274 find_error:
2275 return ret;
2276 }
2277
2278 /*
2279 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
2280 */
2281 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
2282 size_t nb_uri, lttng_sock_cred *creds)
2283 {
2284 int ret;
2285 struct ltt_session *session;
2286 struct snapshot_output *new_output = NULL;
2287
2288 assert(name);
2289 assert(creds);
2290
2291 /*
2292 * Create session in no output mode with URIs set to NULL. The uris we've
2293 * received are for a default snapshot output if one.
2294 */
2295 ret = cmd_create_session_uri(name, NULL, 0, creds, -1);
2296 if (ret != LTTNG_OK) {
2297 goto error;
2298 }
2299
2300 /* Get the newly created session pointer back. This should NEVER fail. */
2301 session = session_find_by_name(name);
2302 assert(session);
2303
2304 /* Flag session for snapshot mode. */
2305 session->snapshot_mode = 1;
2306
2307 /* Skip snapshot output creation if no URI is given. */
2308 if (nb_uri == 0) {
2309 goto end;
2310 }
2311
2312 new_output = snapshot_output_alloc();
2313 if (!new_output) {
2314 ret = LTTNG_ERR_NOMEM;
2315 goto error_snapshot_alloc;
2316 }
2317
2318 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
2319 uris, nb_uri, session->consumer, new_output, &session->snapshot);
2320 if (ret < 0) {
2321 if (ret == -ENOMEM) {
2322 ret = LTTNG_ERR_NOMEM;
2323 } else {
2324 ret = LTTNG_ERR_INVALID;
2325 }
2326 goto error_snapshot;
2327 }
2328
2329 rcu_read_lock();
2330 snapshot_add_output(&session->snapshot, new_output);
2331 rcu_read_unlock();
2332
2333 end:
2334 return LTTNG_OK;
2335
2336 error_snapshot:
2337 snapshot_output_destroy(new_output);
2338 error_snapshot_alloc:
2339 session_destroy(session);
2340 error:
2341 return ret;
2342 }
2343
2344 /*
2345 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2346 *
2347 * Called with session lock held.
2348 */
2349 int cmd_destroy_session(struct ltt_session *session, int wpipe)
2350 {
2351 int ret;
2352 struct ltt_ust_session *usess;
2353 struct ltt_kernel_session *ksess;
2354
2355 /* Safety net */
2356 assert(session);
2357
2358 usess = session->ust_session;
2359 ksess = session->kernel_session;
2360
2361 /* Clean kernel session teardown */
2362 kernel_destroy_session(ksess);
2363
2364 /* UST session teardown */
2365 if (usess) {
2366 /* Close any relayd session */
2367 consumer_output_send_destroy_relayd(usess->consumer);
2368
2369 /* Destroy every UST application related to this session. */
2370 ret = ust_app_destroy_trace_all(usess);
2371 if (ret) {
2372 ERR("Error in ust_app_destroy_trace_all");
2373 }
2374
2375 /* Clean up the rest. */
2376 trace_ust_destroy_session(usess);
2377 }
2378
2379 /*
2380 * Must notify the kernel thread here to update it's poll set in order to
2381 * remove the channel(s)' fd just destroyed.
2382 */
2383 ret = notify_thread_pipe(wpipe);
2384 if (ret < 0) {
2385 PERROR("write kernel poll pipe");
2386 }
2387
2388 ret = session_destroy(session);
2389
2390 return ret;
2391 }
2392
2393 /*
2394 * Command LTTNG_CALIBRATE processed by the client thread.
2395 */
2396 int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2397 {
2398 int ret;
2399
2400 switch (domain) {
2401 case LTTNG_DOMAIN_KERNEL:
2402 {
2403 struct lttng_kernel_calibrate kcalibrate;
2404
2405 switch (calibrate->type) {
2406 case LTTNG_CALIBRATE_FUNCTION:
2407 default:
2408 /* Default and only possible calibrate option. */
2409 kcalibrate.type = LTTNG_KERNEL_CALIBRATE_KRETPROBE;
2410 break;
2411 }
2412
2413 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2414 if (ret < 0) {
2415 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
2416 goto error;
2417 }
2418 break;
2419 }
2420 case LTTNG_DOMAIN_UST:
2421 {
2422 struct lttng_ust_calibrate ucalibrate;
2423
2424 switch (calibrate->type) {
2425 case LTTNG_CALIBRATE_FUNCTION:
2426 default:
2427 /* Default and only possible calibrate option. */
2428 ucalibrate.type = LTTNG_UST_CALIBRATE_TRACEPOINT;
2429 break;
2430 }
2431
2432 ret = ust_app_calibrate_glb(&ucalibrate);
2433 if (ret < 0) {
2434 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
2435 goto error;
2436 }
2437 break;
2438 }
2439 default:
2440 ret = LTTNG_ERR_UND;
2441 goto error;
2442 }
2443
2444 ret = LTTNG_OK;
2445
2446 error:
2447 return ret;
2448 }
2449
2450 /*
2451 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2452 */
2453 int cmd_register_consumer(struct ltt_session *session, int domain,
2454 const char *sock_path, struct consumer_data *cdata)
2455 {
2456 int ret, sock;
2457 struct consumer_socket *socket = NULL;
2458
2459 assert(session);
2460 assert(cdata);
2461 assert(sock_path);
2462
2463 switch (domain) {
2464 case LTTNG_DOMAIN_KERNEL:
2465 {
2466 struct ltt_kernel_session *ksess = session->kernel_session;
2467
2468 assert(ksess);
2469
2470 /* Can't register a consumer if there is already one */
2471 if (ksess->consumer_fds_sent != 0) {
2472 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2473 goto error;
2474 }
2475
2476 sock = lttcomm_connect_unix_sock(sock_path);
2477 if (sock < 0) {
2478 ret = LTTNG_ERR_CONNECT_FAIL;
2479 goto error;
2480 }
2481 cdata->cmd_sock = sock;
2482
2483 socket = consumer_allocate_socket(&cdata->cmd_sock);
2484 if (socket == NULL) {
2485 ret = close(sock);
2486 if (ret < 0) {
2487 PERROR("close register consumer");
2488 }
2489 cdata->cmd_sock = -1;
2490 ret = LTTNG_ERR_FATAL;
2491 goto error;
2492 }
2493
2494 socket->lock = zmalloc(sizeof(pthread_mutex_t));
2495 if (socket->lock == NULL) {
2496 PERROR("zmalloc pthread mutex");
2497 ret = LTTNG_ERR_FATAL;
2498 goto error;
2499 }
2500 pthread_mutex_init(socket->lock, NULL);
2501 socket->registered = 1;
2502
2503 rcu_read_lock();
2504 consumer_add_socket(socket, ksess->consumer);
2505 rcu_read_unlock();
2506
2507 pthread_mutex_lock(&cdata->pid_mutex);
2508 cdata->pid = -1;
2509 pthread_mutex_unlock(&cdata->pid_mutex);
2510
2511 break;
2512 }
2513 default:
2514 /* TODO: Userspace tracing */
2515 ret = LTTNG_ERR_UND;
2516 goto error;
2517 }
2518
2519 return LTTNG_OK;
2520
2521 error:
2522 if (socket) {
2523 consumer_destroy_socket(socket);
2524 }
2525 return ret;
2526 }
2527
2528 /*
2529 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2530 */
2531 ssize_t cmd_list_domains(struct ltt_session *session,
2532 struct lttng_domain **domains)
2533 {
2534 int ret, index = 0;
2535 ssize_t nb_dom = 0;
2536 struct agent *agt;
2537 struct lttng_ht_iter iter;
2538
2539 if (session->kernel_session != NULL) {
2540 DBG3("Listing domains found kernel domain");
2541 nb_dom++;
2542 }
2543
2544 if (session->ust_session != NULL) {
2545 DBG3("Listing domains found UST global domain");
2546 nb_dom++;
2547
2548 rcu_read_lock();
2549 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2550 agt, node.node) {
2551 if (agt->being_used) {
2552 nb_dom++;
2553 }
2554 }
2555 rcu_read_unlock();
2556 }
2557
2558 if (!nb_dom) {
2559 goto end;
2560 }
2561
2562 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2563 if (*domains == NULL) {
2564 ret = LTTNG_ERR_FATAL;
2565 goto error;
2566 }
2567
2568 if (session->kernel_session != NULL) {
2569 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2570
2571 /* Kernel session buffer type is always GLOBAL */
2572 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
2573
2574 index++;
2575 }
2576
2577 if (session->ust_session != NULL) {
2578 (*domains)[index].type = LTTNG_DOMAIN_UST;
2579 (*domains)[index].buf_type = session->ust_session->buffer_type;
2580 index++;
2581
2582 rcu_read_lock();
2583 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2584 agt, node.node) {
2585 if (agt->being_used) {
2586 (*domains)[index].type = agt->domain;
2587 (*domains)[index].buf_type = session->ust_session->buffer_type;
2588 index++;
2589 }
2590 }
2591 rcu_read_unlock();
2592 }
2593 end:
2594 return nb_dom;
2595
2596 error:
2597 /* Return negative value to differentiate return code */
2598 return -ret;
2599 }
2600
2601
2602 /*
2603 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2604 */
2605 ssize_t cmd_list_channels(int domain, struct ltt_session *session,
2606 struct lttng_channel **channels)
2607 {
2608 int ret;
2609 ssize_t nb_chan = 0;
2610
2611 switch (domain) {
2612 case LTTNG_DOMAIN_KERNEL:
2613 if (session->kernel_session != NULL) {
2614 nb_chan = session->kernel_session->channel_count;
2615 }
2616 DBG3("Number of kernel channels %zd", nb_chan);
2617 if (nb_chan <= 0) {
2618 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
2619 }
2620 break;
2621 case LTTNG_DOMAIN_UST:
2622 if (session->ust_session != NULL) {
2623 rcu_read_lock();
2624 nb_chan = lttng_ht_get_count(
2625 session->ust_session->domain_global.channels);
2626 rcu_read_unlock();
2627 }
2628 DBG3("Number of UST global channels %zd", nb_chan);
2629 if (nb_chan < 0) {
2630 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2631 goto error;
2632 }
2633 break;
2634 default:
2635 ret = LTTNG_ERR_UND;
2636 goto error;
2637 }
2638
2639 if (nb_chan > 0) {
2640 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
2641 if (*channels == NULL) {
2642 ret = LTTNG_ERR_FATAL;
2643 goto error;
2644 }
2645
2646 list_lttng_channels(domain, session, *channels);
2647 }
2648
2649 return nb_chan;
2650
2651 error:
2652 /* Return negative value to differentiate return code */
2653 return -ret;
2654 }
2655
2656 /*
2657 * Command LTTNG_LIST_EVENTS processed by the client thread.
2658 */
2659 ssize_t cmd_list_events(int domain, struct ltt_session *session,
2660 char *channel_name, struct lttng_event **events)
2661 {
2662 int ret = 0;
2663 ssize_t nb_event = 0;
2664
2665 switch (domain) {
2666 case LTTNG_DOMAIN_KERNEL:
2667 if (session->kernel_session != NULL) {
2668 nb_event = list_lttng_kernel_events(channel_name,
2669 session->kernel_session, events);
2670 }
2671 break;
2672 case LTTNG_DOMAIN_UST:
2673 {
2674 if (session->ust_session != NULL) {
2675 nb_event = list_lttng_ust_global_events(channel_name,
2676 &session->ust_session->domain_global, events);
2677 }
2678 break;
2679 }
2680 case LTTNG_DOMAIN_LOG4J:
2681 case LTTNG_DOMAIN_JUL:
2682 case LTTNG_DOMAIN_PYTHON:
2683 if (session->ust_session) {
2684 struct lttng_ht_iter iter;
2685 struct agent *agt;
2686
2687 rcu_read_lock();
2688 cds_lfht_for_each_entry(session->ust_session->agents->ht,
2689 &iter.iter, agt, node.node) {
2690 nb_event = list_lttng_agent_events(agt, events);
2691 }
2692 rcu_read_unlock();
2693 }
2694 break;
2695 default:
2696 ret = LTTNG_ERR_UND;
2697 goto error;
2698 }
2699
2700 return nb_event;
2701
2702 error:
2703 /* Return negative value to differentiate return code */
2704 return -ret;
2705 }
2706
2707 /*
2708 * Using the session list, filled a lttng_session array to send back to the
2709 * client for session listing.
2710 *
2711 * The session list lock MUST be acquired before calling this function. Use
2712 * session_lock_list() and session_unlock_list().
2713 */
2714 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2715 gid_t gid)
2716 {
2717 int ret;
2718 unsigned int i = 0;
2719 struct ltt_session *session;
2720 struct ltt_session_list *list = session_get_list();
2721
2722 DBG("Getting all available session for UID %d GID %d",
2723 uid, gid);
2724 /*
2725 * Iterate over session list and append data after the control struct in
2726 * the buffer.
2727 */
2728 cds_list_for_each_entry(session, &list->head, list) {
2729 /*
2730 * Only list the sessions the user can control.
2731 */
2732 if (!session_access_ok(session, uid, gid)) {
2733 continue;
2734 }
2735
2736 struct ltt_kernel_session *ksess = session->kernel_session;
2737 struct ltt_ust_session *usess = session->ust_session;
2738
2739 if (session->consumer->type == CONSUMER_DST_NET ||
2740 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2741 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2742 ret = build_network_session_path(sessions[i].path,
2743 sizeof(sessions[i].path), session);
2744 } else {
2745 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
2746 session->consumer->dst.trace_path);
2747 }
2748 if (ret < 0) {
2749 PERROR("snprintf session path");
2750 continue;
2751 }
2752
2753 strncpy(sessions[i].name, session->name, NAME_MAX);
2754 sessions[i].name[NAME_MAX - 1] = '\0';
2755 sessions[i].enabled = session->active;
2756 sessions[i].snapshot_mode = session->snapshot_mode;
2757 sessions[i].live_timer_interval = session->live_timer;
2758 i++;
2759 }
2760 }
2761
2762 /*
2763 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2764 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
2765 */
2766 int cmd_data_pending(struct ltt_session *session)
2767 {
2768 int ret;
2769 struct ltt_kernel_session *ksess = session->kernel_session;
2770 struct ltt_ust_session *usess = session->ust_session;
2771
2772 assert(session);
2773
2774 /* Session MUST be stopped to ask for data availability. */
2775 if (session->active) {
2776 ret = LTTNG_ERR_SESSION_STARTED;
2777 goto error;
2778 } else {
2779 /*
2780 * If stopped, just make sure we've started before else the above call
2781 * will always send that there is data pending.
2782 *
2783 * The consumer assumes that when the data pending command is received,
2784 * the trace has been started before or else no output data is written
2785 * by the streams which is a condition for data pending. So, this is
2786 * *VERY* important that we don't ask the consumer before a start
2787 * trace.
2788 */
2789 if (!session->has_been_started) {
2790 ret = 0;
2791 goto error;
2792 }
2793 }
2794
2795 if (ksess && ksess->consumer) {
2796 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2797 if (ret == 1) {
2798 /* Data is still being extracted for the kernel. */
2799 goto error;
2800 }
2801 }
2802
2803 if (usess && usess->consumer) {
2804 ret = consumer_is_data_pending(usess->id, usess->consumer);
2805 if (ret == 1) {
2806 /* Data is still being extracted for the kernel. */
2807 goto error;
2808 }
2809 }
2810
2811 /* Data is ready to be read by a viewer */
2812 ret = 0;
2813
2814 error:
2815 return ret;
2816 }
2817
2818 /*
2819 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
2820 *
2821 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2822 */
2823 int cmd_snapshot_add_output(struct ltt_session *session,
2824 struct lttng_snapshot_output *output, uint32_t *id)
2825 {
2826 int ret;
2827 struct snapshot_output *new_output;
2828
2829 assert(session);
2830 assert(output);
2831
2832 DBG("Cmd snapshot add output for session %s", session->name);
2833
2834 /*
2835 * Permission denied to create an output if the session is not
2836 * set in no output mode.
2837 */
2838 if (session->output_traces) {
2839 ret = LTTNG_ERR_EPERM;
2840 goto error;
2841 }
2842
2843 /* Only one output is allowed until we have the "tee" feature. */
2844 if (session->snapshot.nb_output == 1) {
2845 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
2846 goto error;
2847 }
2848
2849 new_output = snapshot_output_alloc();
2850 if (!new_output) {
2851 ret = LTTNG_ERR_NOMEM;
2852 goto error;
2853 }
2854
2855 ret = snapshot_output_init(output->max_size, output->name,
2856 output->ctrl_url, output->data_url, session->consumer, new_output,
2857 &session->snapshot);
2858 if (ret < 0) {
2859 if (ret == -ENOMEM) {
2860 ret = LTTNG_ERR_NOMEM;
2861 } else {
2862 ret = LTTNG_ERR_INVALID;
2863 }
2864 goto free_error;
2865 }
2866
2867 rcu_read_lock();
2868 snapshot_add_output(&session->snapshot, new_output);
2869 if (id) {
2870 *id = new_output->id;
2871 }
2872 rcu_read_unlock();
2873
2874 return LTTNG_OK;
2875
2876 free_error:
2877 snapshot_output_destroy(new_output);
2878 error:
2879 return ret;
2880 }
2881
2882 /*
2883 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
2884 *
2885 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2886 */
2887 int cmd_snapshot_del_output(struct ltt_session *session,
2888 struct lttng_snapshot_output *output)
2889 {
2890 int ret;
2891 struct snapshot_output *sout = NULL;
2892
2893 assert(session);
2894 assert(output);
2895
2896 rcu_read_lock();
2897
2898 /*
2899 * Permission denied to create an output if the session is not
2900 * set in no output mode.
2901 */
2902 if (session->output_traces) {
2903 ret = LTTNG_ERR_EPERM;
2904 goto error;
2905 }
2906
2907 if (output->id) {
2908 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
2909 session->name);
2910 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
2911 } else if (*output->name != '\0') {
2912 DBG("Cmd snapshot del output name %s for session %s", output->name,
2913 session->name);
2914 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
2915 }
2916 if (!sout) {
2917 ret = LTTNG_ERR_INVALID;
2918 goto error;
2919 }
2920
2921 snapshot_delete_output(&session->snapshot, sout);
2922 snapshot_output_destroy(sout);
2923 ret = LTTNG_OK;
2924
2925 error:
2926 rcu_read_unlock();
2927 return ret;
2928 }
2929
2930 /*
2931 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
2932 *
2933 * If no output is available, outputs is untouched and 0 is returned.
2934 *
2935 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
2936 */
2937 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
2938 struct lttng_snapshot_output **outputs)
2939 {
2940 int ret, idx = 0;
2941 struct lttng_snapshot_output *list = NULL;
2942 struct lttng_ht_iter iter;
2943 struct snapshot_output *output;
2944
2945 assert(session);
2946 assert(outputs);
2947
2948 DBG("Cmd snapshot list outputs for session %s", session->name);
2949
2950 /*
2951 * Permission denied to create an output if the session is not
2952 * set in no output mode.
2953 */
2954 if (session->output_traces) {
2955 ret = -LTTNG_ERR_EPERM;
2956 goto error;
2957 }
2958
2959 if (session->snapshot.nb_output == 0) {
2960 ret = 0;
2961 goto error;
2962 }
2963
2964 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
2965 if (!list) {
2966 ret = -LTTNG_ERR_NOMEM;
2967 goto error;
2968 }
2969
2970 /* Copy list from session to the new list object. */
2971 rcu_read_lock();
2972 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
2973 output, node.node) {
2974 assert(output->consumer);
2975 list[idx].id = output->id;
2976 list[idx].max_size = output->max_size;
2977 strncpy(list[idx].name, output->name, sizeof(list[idx].name));
2978 if (output->consumer->type == CONSUMER_DST_LOCAL) {
2979 strncpy(list[idx].ctrl_url, output->consumer->dst.trace_path,
2980 sizeof(list[idx].ctrl_url));
2981 } else {
2982 /* Control URI. */
2983 ret = uri_to_str_url(&output->consumer->dst.net.control,
2984 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
2985 if (ret < 0) {
2986 ret = -LTTNG_ERR_NOMEM;
2987 goto error;
2988 }
2989
2990 /* Data URI. */
2991 ret = uri_to_str_url(&output->consumer->dst.net.data,
2992 list[idx].data_url, sizeof(list[idx].data_url));
2993 if (ret < 0) {
2994 ret = -LTTNG_ERR_NOMEM;
2995 goto error;
2996 }
2997 }
2998 idx++;
2999 }
3000
3001 *outputs = list;
3002 list = NULL;
3003 ret = session->snapshot.nb_output;
3004 error:
3005 free(list);
3006 rcu_read_unlock();
3007 return ret;
3008 }
3009
3010 /*
3011 * Send relayd sockets from snapshot output to consumer. Ignore request if the
3012 * snapshot output is *not* set with a remote destination.
3013 *
3014 * Return 0 on success or a LTTNG_ERR code.
3015 */
3016 static int set_relayd_for_snapshot(struct consumer_output *consumer,
3017 struct snapshot_output *snap_output, struct ltt_session *session)
3018 {
3019 int ret = LTTNG_OK;
3020 struct lttng_ht_iter iter;
3021 struct consumer_socket *socket;
3022
3023 assert(consumer);
3024 assert(snap_output);
3025 assert(session);
3026
3027 DBG2("Set relayd object from snapshot output");
3028
3029 /* Ignore if snapshot consumer output is not network. */
3030 if (snap_output->consumer->type != CONSUMER_DST_NET) {
3031 goto error;
3032 }
3033
3034 /*
3035 * For each consumer socket, create and send the relayd object of the
3036 * snapshot output.
3037 */
3038 rcu_read_lock();
3039 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
3040 socket, node.node) {
3041 ret = send_consumer_relayd_sockets(0, session->id,
3042 snap_output->consumer, socket,
3043 session->name, session->hostname,
3044 session->live_timer);
3045 if (ret != LTTNG_OK) {
3046 rcu_read_unlock();
3047 goto error;
3048 }
3049 }
3050 rcu_read_unlock();
3051
3052 error:
3053 return ret;
3054 }
3055
3056 /*
3057 * Record a kernel snapshot.
3058 *
3059 * Return LTTNG_OK on success or a LTTNG_ERR code.
3060 */
3061 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
3062 struct snapshot_output *output, struct ltt_session *session,
3063 int wait, uint64_t nb_packets_per_stream)
3064 {
3065 int ret;
3066
3067 assert(ksess);
3068 assert(output);
3069 assert(session);
3070
3071 /* Get the datetime for the snapshot output directory. */
3072 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
3073 sizeof(output->datetime));
3074 if (!ret) {
3075 ret = LTTNG_ERR_INVALID;
3076 goto error;
3077 }
3078
3079 /*
3080 * Copy kernel session sockets so we can communicate with the right
3081 * consumer for the snapshot record command.
3082 */
3083 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
3084 if (ret < 0) {
3085 ret = LTTNG_ERR_NOMEM;
3086 goto error;
3087 }
3088
3089 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
3090 if (ret != LTTNG_OK) {
3091 goto error_snapshot;
3092 }
3093
3094 ret = kernel_snapshot_record(ksess, output, wait, nb_packets_per_stream);
3095 if (ret != LTTNG_OK) {
3096 goto error_snapshot;
3097 }
3098
3099 ret = LTTNG_OK;
3100 goto end;
3101
3102 error_snapshot:
3103 /* Clean up copied sockets so this output can use some other later on. */
3104 consumer_destroy_output_sockets(output->consumer);
3105 error:
3106 end:
3107 return ret;
3108 }
3109
3110 /*
3111 * Record a UST snapshot.
3112 *
3113 * Return 0 on success or a LTTNG_ERR error code.
3114 */
3115 static int record_ust_snapshot(struct ltt_ust_session *usess,
3116 struct snapshot_output *output, struct ltt_session *session,
3117 int wait, uint64_t nb_packets_per_stream)
3118 {
3119 int ret;
3120
3121 assert(usess);
3122 assert(output);
3123 assert(session);
3124
3125 /* Get the datetime for the snapshot output directory. */
3126 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
3127 sizeof(output->datetime));
3128 if (!ret) {
3129 ret = LTTNG_ERR_INVALID;
3130 goto error;
3131 }
3132
3133 /*
3134 * Copy UST session sockets so we can communicate with the right
3135 * consumer for the snapshot record command.
3136 */
3137 ret = consumer_copy_sockets(output->consumer, usess->consumer);
3138 if (ret < 0) {
3139 ret = LTTNG_ERR_NOMEM;
3140 goto error;
3141 }
3142
3143 ret = set_relayd_for_snapshot(usess->consumer, output, session);
3144 if (ret != LTTNG_OK) {
3145 goto error_snapshot;
3146 }
3147
3148 ret = ust_app_snapshot_record(usess, output, wait, nb_packets_per_stream);
3149 if (ret < 0) {
3150 switch (-ret) {
3151 case EINVAL:
3152 ret = LTTNG_ERR_INVALID;
3153 break;
3154 case ENODATA:
3155 ret = LTTNG_ERR_SNAPSHOT_NODATA;
3156 break;
3157 default:
3158 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3159 break;
3160 }
3161 goto error_snapshot;
3162 }
3163
3164 ret = LTTNG_OK;
3165
3166 error_snapshot:
3167 /* Clean up copied sockets so this output can use some other later on. */
3168 consumer_destroy_output_sockets(output->consumer);
3169 error:
3170 return ret;
3171 }
3172
3173 static
3174 uint64_t get_session_size_one_more_packet_per_stream(struct ltt_session *session,
3175 uint64_t cur_nr_packets)
3176 {
3177 uint64_t tot_size = 0;
3178
3179 if (session->kernel_session) {
3180 struct ltt_kernel_channel *chan;
3181 struct ltt_kernel_session *ksess = session->kernel_session;
3182
3183 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
3184 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
3185 /*
3186 * Don't take channel into account if we
3187 * already grab all its packets.
3188 */
3189 continue;
3190 }
3191 tot_size += chan->channel->attr.subbuf_size
3192 * chan->stream_count;
3193 }
3194 }
3195
3196 if (session->ust_session) {
3197 struct ltt_ust_session *usess = session->ust_session;
3198
3199 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
3200 cur_nr_packets);
3201 }
3202
3203 return tot_size;
3204 }
3205
3206 /*
3207 * Calculate the number of packets we can grab from each stream that
3208 * fits within the overall snapshot max size.
3209 *
3210 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
3211 * the number of packets per stream.
3212 *
3213 * TODO: this approach is not perfect: we consider the worse case
3214 * (packet filling the sub-buffers) as an upper bound, but we could do
3215 * better if we do this calculation while we actually grab the packet
3216 * content: we would know how much padding we don't actually store into
3217 * the file.
3218 *
3219 * This algorithm is currently bounded by the number of packets per
3220 * stream.
3221 *
3222 * Since we call this algorithm before actually grabbing the data, it's
3223 * an approximation: for instance, applications could appear/disappear
3224 * in between this call and actually grabbing data.
3225 */
3226 static
3227 int64_t get_session_nb_packets_per_stream(struct ltt_session *session, uint64_t max_size)
3228 {
3229 int64_t size_left;
3230 uint64_t cur_nb_packets = 0;
3231
3232 if (!max_size) {
3233 return 0; /* Infinite */
3234 }
3235
3236 size_left = max_size;
3237 for (;;) {
3238 uint64_t one_more_packet_tot_size;
3239
3240 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(session,
3241 cur_nb_packets);
3242 if (!one_more_packet_tot_size) {
3243 /* We are already grabbing all packets. */
3244 break;
3245 }
3246 size_left -= one_more_packet_tot_size;
3247 if (size_left < 0) {
3248 break;
3249 }
3250 cur_nb_packets++;
3251 }
3252 if (!cur_nb_packets) {
3253 /* Not enough room to grab one packet of each stream, error. */
3254 return -1;
3255 }
3256 return cur_nb_packets;
3257 }
3258
3259 /*
3260 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
3261 *
3262 * The wait parameter is ignored so this call always wait for the snapshot to
3263 * complete before returning.
3264 *
3265 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3266 */
3267 int cmd_snapshot_record(struct ltt_session *session,
3268 struct lttng_snapshot_output *output, int wait)
3269 {
3270 int ret = LTTNG_OK;
3271 unsigned int use_tmp_output = 0;
3272 struct snapshot_output tmp_output;
3273 unsigned int snapshot_success = 0;
3274
3275 assert(session);
3276 assert(output);
3277
3278 DBG("Cmd snapshot record for session %s", session->name);
3279
3280 /*
3281 * Permission denied to create an output if the session is not
3282 * set in no output mode.
3283 */
3284 if (session->output_traces) {
3285 ret = LTTNG_ERR_EPERM;
3286 goto error;
3287 }
3288
3289 /* The session needs to be started at least once. */
3290 if (!session->has_been_started) {
3291 ret = LTTNG_ERR_START_SESSION_ONCE;
3292 goto error;
3293 }
3294
3295 /* Use temporary output for the session. */
3296 if (*output->ctrl_url != '\0') {
3297 ret = snapshot_output_init(output->max_size, output->name,
3298 output->ctrl_url, output->data_url, session->consumer,
3299 &tmp_output, NULL);
3300 if (ret < 0) {
3301 if (ret == -ENOMEM) {
3302 ret = LTTNG_ERR_NOMEM;
3303 } else {
3304 ret = LTTNG_ERR_INVALID;
3305 }
3306 goto error;
3307 }
3308 /* Use the global session count for the temporary snapshot. */
3309 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3310 use_tmp_output = 1;
3311 }
3312
3313 if (session->kernel_session) {
3314 struct ltt_kernel_session *ksess = session->kernel_session;
3315
3316 if (use_tmp_output) {
3317 int64_t nb_packets_per_stream;
3318
3319 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3320 tmp_output.max_size);
3321 if (nb_packets_per_stream < 0) {
3322 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3323 goto error;
3324 }
3325 ret = record_kernel_snapshot(ksess, &tmp_output, session,
3326 wait, nb_packets_per_stream);
3327 if (ret != LTTNG_OK) {
3328 goto error;
3329 }
3330 snapshot_success = 1;
3331 } else {
3332 struct snapshot_output *sout;
3333 struct lttng_ht_iter iter;
3334
3335 rcu_read_lock();
3336 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3337 &iter.iter, sout, node.node) {
3338 int64_t nb_packets_per_stream;
3339
3340 /*
3341 * Make a local copy of the output and assign the possible
3342 * temporary value given by the caller.
3343 */
3344 memset(&tmp_output, 0, sizeof(tmp_output));
3345 memcpy(&tmp_output, sout, sizeof(tmp_output));
3346
3347 if (output->max_size != (uint64_t) -1ULL) {
3348 tmp_output.max_size = output->max_size;
3349 }
3350
3351 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3352 tmp_output.max_size);
3353 if (nb_packets_per_stream < 0) {
3354 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3355 goto error;
3356 }
3357
3358 /* Use temporary name. */
3359 if (*output->name != '\0') {
3360 strncpy(tmp_output.name, output->name,
3361 sizeof(tmp_output.name));
3362 }
3363
3364 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3365
3366 ret = record_kernel_snapshot(ksess, &tmp_output,
3367 session, wait, nb_packets_per_stream);
3368 if (ret != LTTNG_OK) {
3369 rcu_read_unlock();
3370 goto error;
3371 }
3372 snapshot_success = 1;
3373 }
3374 rcu_read_unlock();
3375 }
3376 }
3377
3378 if (session->ust_session) {
3379 struct ltt_ust_session *usess = session->ust_session;
3380
3381 if (use_tmp_output) {
3382 int64_t nb_packets_per_stream;
3383
3384 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3385 tmp_output.max_size);
3386 if (nb_packets_per_stream < 0) {
3387 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3388 goto error;
3389 }
3390 ret = record_ust_snapshot(usess, &tmp_output, session,
3391 wait, nb_packets_per_stream);
3392 if (ret != LTTNG_OK) {
3393 goto error;
3394 }
3395 snapshot_success = 1;
3396 } else {
3397 struct snapshot_output *sout;
3398 struct lttng_ht_iter iter;
3399
3400 rcu_read_lock();
3401 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3402 &iter.iter, sout, node.node) {
3403 int64_t nb_packets_per_stream;
3404
3405 /*
3406 * Make a local copy of the output and assign the possible
3407 * temporary value given by the caller.
3408 */
3409 memset(&tmp_output, 0, sizeof(tmp_output));
3410 memcpy(&tmp_output, sout, sizeof(tmp_output));
3411
3412 if (output->max_size != (uint64_t) -1ULL) {
3413 tmp_output.max_size = output->max_size;
3414 }
3415
3416 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3417 tmp_output.max_size);
3418 if (nb_packets_per_stream < 0) {
3419 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3420 rcu_read_unlock();
3421 goto error;
3422 }
3423
3424 /* Use temporary name. */
3425 if (*output->name != '\0') {
3426 strncpy(tmp_output.name, output->name,
3427 sizeof(tmp_output.name));
3428 }
3429
3430 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3431
3432 ret = record_ust_snapshot(usess, &tmp_output, session,
3433 wait, nb_packets_per_stream);
3434 if (ret != LTTNG_OK) {
3435 rcu_read_unlock();
3436 goto error;
3437 }
3438 snapshot_success = 1;
3439 }
3440 rcu_read_unlock();
3441 }
3442 }
3443
3444 if (snapshot_success) {
3445 session->snapshot.nb_snapshot++;
3446 } else {
3447 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3448 }
3449
3450 error:
3451 return ret;
3452 }
3453
3454 /*
3455 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
3456 */
3457 int cmd_set_session_shm_path(struct ltt_session *session,
3458 const char *shm_path)
3459 {
3460 /* Safety net */
3461 assert(session);
3462
3463 /*
3464 * Can only set shm path before session is started.
3465 */
3466 if (session->has_been_started) {
3467 return LTTNG_ERR_SESSION_STARTED;
3468 }
3469
3470 strncpy(session->shm_path, shm_path,
3471 sizeof(session->shm_path));
3472 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
3473
3474 return 0;
3475 }
3476
3477 /*
3478 * Init command subsystem.
3479 */
3480 void cmd_init(void)
3481 {
3482 /*
3483 * Set network sequence index to 1 for streams to match a relayd
3484 * socket on the consumer side.
3485 */
3486 pthread_mutex_lock(&relayd_net_seq_idx_lock);
3487 relayd_net_seq_idx = 1;
3488 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
3489
3490 DBG("Command subsystem initialized");
3491 }
LTTng 2.0 tools and control repository
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