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Fix: keep active session state on redundant start command
[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c
1 /*
2 * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
3 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License, version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 51
16 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #define _LGPL_SOURCE
20 #include <assert.h>
21 #include <inttypes.h>
22 #include <urcu/list.h>
23 #include <urcu/uatomic.h>
24 #include <sys/stat.h>
25 #include <stdio.h>
26
27 #include <common/defaults.h>
28 #include <common/common.h>
29 #include <common/sessiond-comm/sessiond-comm.h>
30 #include <common/relayd/relayd.h>
31 #include <common/utils.h>
32 #include <common/compat/string.h>
33 #include <common/kernel-ctl/kernel-ctl.h>
34 #include <common/dynamic-buffer.h>
35 #include <common/buffer-view.h>
36 #include <common/trace-chunk.h>
37 #include <lttng/location-internal.h>
38 #include <lttng/trigger/trigger-internal.h>
39 #include <lttng/condition/condition.h>
40 #include <lttng/action/action.h>
41 #include <lttng/channel.h>
42 #include <lttng/channel-internal.h>
43 #include <lttng/rotate-internal.h>
44 #include <lttng/location-internal.h>
45 #include <lttng/session-internal.h>
46 #include <lttng/userspace-probe-internal.h>
47 #include <lttng/session-descriptor-internal.h>
48 #include <common/string-utils/string-utils.h>
49
50 #include "channel.h"
51 #include "consumer.h"
52 #include "event.h"
53 #include "health-sessiond.h"
54 #include "kernel.h"
55 #include "kernel-consumer.h"
56 #include "lttng-sessiond.h"
57 #include "utils.h"
58 #include "lttng-syscall.h"
59 #include "agent.h"
60 #include "buffer-registry.h"
61 #include "notification-thread.h"
62 #include "notification-thread-commands.h"
63 #include "rotate.h"
64 #include "rotation-thread.h"
65 #include "timer.h"
66 #include "agent-thread.h"
67
68 #include "cmd.h"
69
70 /* Sleep for 100ms between each check for the shm path's deletion. */
71 #define SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US 100000
72
73 struct cmd_destroy_session_reply_context {
74 int reply_sock_fd;
75 bool implicit_rotation_on_destroy;
76 /*
77 * Indicates whether or not an error occurred while launching the
78 * destruction of a session.
79 */
80 enum lttng_error_code destruction_status;
81 };
82
83 static enum lttng_error_code wait_on_path(void *path);
84
85 /*
86 * Command completion handler that is used by the destroy command
87 * when a session that has a non-default shm_path is being destroyed.
88 *
89 * See comment in cmd_destroy_session() for the rationale.
90 */
91 static struct destroy_completion_handler {
92 struct cmd_completion_handler handler;
93 char shm_path[member_sizeof(struct ltt_session, shm_path)];
94 } destroy_completion_handler = {
95 .handler = {
96 .run = wait_on_path,
97 .data = destroy_completion_handler.shm_path
98 },
99 .shm_path = { 0 },
100 };
101
102 static struct cmd_completion_handler *current_completion_handler;
103
104 /*
105 * Used to keep a unique index for each relayd socket created where this value
106 * is associated with streams on the consumer so it can match the right relayd
107 * to send to. It must be accessed with the relayd_net_seq_idx_lock
108 * held.
109 */
110 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
111 static uint64_t relayd_net_seq_idx;
112
113 static int validate_ust_event_name(const char *);
114 static int cmd_enable_event_internal(struct ltt_session *session,
115 const struct lttng_domain *domain,
116 char *channel_name, struct lttng_event *event,
117 char *filter_expression,
118 struct lttng_filter_bytecode *filter,
119 struct lttng_event_exclusion *exclusion,
120 int wpipe);
121
122 /*
123 * Create a session path used by list_lttng_sessions for the case that the
124 * session consumer is on the network.
125 */
126 static int build_network_session_path(char *dst, size_t size,
127 struct ltt_session *session)
128 {
129 int ret, kdata_port, udata_port;
130 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
131 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
132
133 assert(session);
134 assert(dst);
135
136 memset(tmp_urls, 0, sizeof(tmp_urls));
137 memset(tmp_uurl, 0, sizeof(tmp_uurl));
138
139 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
140
141 if (session->kernel_session && session->kernel_session->consumer) {
142 kuri = &session->kernel_session->consumer->dst.net.control;
143 kdata_port = session->kernel_session->consumer->dst.net.data.port;
144 }
145
146 if (session->ust_session && session->ust_session->consumer) {
147 uuri = &session->ust_session->consumer->dst.net.control;
148 udata_port = session->ust_session->consumer->dst.net.data.port;
149 }
150
151 if (uuri == NULL && kuri == NULL) {
152 uri = &session->consumer->dst.net.control;
153 kdata_port = session->consumer->dst.net.data.port;
154 } else if (kuri && uuri) {
155 ret = uri_compare(kuri, uuri);
156 if (ret) {
157 /* Not Equal */
158 uri = kuri;
159 /* Build uuri URL string */
160 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
161 if (ret < 0) {
162 goto error;
163 }
164 } else {
165 uri = kuri;
166 }
167 } else if (kuri && uuri == NULL) {
168 uri = kuri;
169 } else if (uuri && kuri == NULL) {
170 uri = uuri;
171 }
172
173 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
174 if (ret < 0) {
175 goto error;
176 }
177
178 /*
179 * Do we have a UST url set. If yes, this means we have both kernel and UST
180 * to print.
181 */
182 if (*tmp_uurl != '\0') {
183 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
184 tmp_urls, kdata_port, tmp_uurl, udata_port);
185 } else {
186 int dport;
187 if (kuri || (!kuri && !uuri)) {
188 dport = kdata_port;
189 } else {
190 /* No kernel URI, use the UST port. */
191 dport = udata_port;
192 }
193 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
194 }
195
196 error:
197 return ret;
198 }
199
200 /*
201 * Get run-time attributes if the session has been started (discarded events,
202 * lost packets).
203 */
204 static int get_kernel_runtime_stats(struct ltt_session *session,
205 struct ltt_kernel_channel *kchan, uint64_t *discarded_events,
206 uint64_t *lost_packets)
207 {
208 int ret;
209
210 if (!session->has_been_started) {
211 ret = 0;
212 *discarded_events = 0;
213 *lost_packets = 0;
214 goto end;
215 }
216
217 ret = consumer_get_discarded_events(session->id, kchan->key,
218 session->kernel_session->consumer,
219 discarded_events);
220 if (ret < 0) {
221 goto end;
222 }
223
224 ret = consumer_get_lost_packets(session->id, kchan->key,
225 session->kernel_session->consumer,
226 lost_packets);
227 if (ret < 0) {
228 goto end;
229 }
230
231 end:
232 return ret;
233 }
234
235 /*
236 * Get run-time attributes if the session has been started (discarded events,
237 * lost packets).
238 */
239 static int get_ust_runtime_stats(struct ltt_session *session,
240 struct ltt_ust_channel *uchan, uint64_t *discarded_events,
241 uint64_t *lost_packets)
242 {
243 int ret;
244 struct ltt_ust_session *usess;
245
246 if (!discarded_events || !lost_packets) {
247 ret = -1;
248 goto end;
249 }
250
251 usess = session->ust_session;
252 assert(discarded_events);
253 assert(lost_packets);
254
255 if (!usess || !session->has_been_started) {
256 *discarded_events = 0;
257 *lost_packets = 0;
258 ret = 0;
259 goto end;
260 }
261
262 if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
263 ret = ust_app_uid_get_channel_runtime_stats(usess->id,
264 &usess->buffer_reg_uid_list,
265 usess->consumer, uchan->id,
266 uchan->attr.overwrite,
267 discarded_events,
268 lost_packets);
269 } else if (usess->buffer_type == LTTNG_BUFFER_PER_PID) {
270 ret = ust_app_pid_get_channel_runtime_stats(usess,
271 uchan, usess->consumer,
272 uchan->attr.overwrite,
273 discarded_events,
274 lost_packets);
275 if (ret < 0) {
276 goto end;
277 }
278 *discarded_events += uchan->per_pid_closed_app_discarded;
279 *lost_packets += uchan->per_pid_closed_app_lost;
280 } else {
281 ERR("Unsupported buffer type");
282 assert(0);
283 ret = -1;
284 goto end;
285 }
286
287 end:
288 return ret;
289 }
290
291 /*
292 * Fill lttng_channel array of all channels.
293 */
294 static ssize_t list_lttng_channels(enum lttng_domain_type domain,
295 struct ltt_session *session, struct lttng_channel *channels,
296 struct lttng_channel_extended *chan_exts)
297 {
298 int i = 0, ret = 0;
299 struct ltt_kernel_channel *kchan;
300
301 DBG("Listing channels for session %s", session->name);
302
303 switch (domain) {
304 case LTTNG_DOMAIN_KERNEL:
305 /* Kernel channels */
306 if (session->kernel_session != NULL) {
307 cds_list_for_each_entry(kchan,
308 &session->kernel_session->channel_list.head, list) {
309 uint64_t discarded_events, lost_packets;
310 struct lttng_channel_extended *extended;
311
312 extended = (struct lttng_channel_extended *)
313 kchan->channel->attr.extended.ptr;
314
315 ret = get_kernel_runtime_stats(session, kchan,
316 &discarded_events, &lost_packets);
317 if (ret < 0) {
318 goto end;
319 }
320 /* Copy lttng_channel struct to array */
321 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
322 channels[i].enabled = kchan->enabled;
323 chan_exts[i].discarded_events =
324 discarded_events;
325 chan_exts[i].lost_packets = lost_packets;
326 chan_exts[i].monitor_timer_interval =
327 extended->monitor_timer_interval;
328 chan_exts[i].blocking_timeout = 0;
329 i++;
330 }
331 }
332 break;
333 case LTTNG_DOMAIN_UST:
334 {
335 struct lttng_ht_iter iter;
336 struct ltt_ust_channel *uchan;
337
338 rcu_read_lock();
339 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
340 &iter.iter, uchan, node.node) {
341 uint64_t discarded_events = 0, lost_packets = 0;
342
343 if (lttng_strncpy(channels[i].name, uchan->name,
344 LTTNG_SYMBOL_NAME_LEN)) {
345 break;
346 }
347 channels[i].attr.overwrite = uchan->attr.overwrite;
348 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
349 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
350 channels[i].attr.switch_timer_interval =
351 uchan->attr.switch_timer_interval;
352 channels[i].attr.read_timer_interval =
353 uchan->attr.read_timer_interval;
354 channels[i].enabled = uchan->enabled;
355 channels[i].attr.tracefile_size = uchan->tracefile_size;
356 channels[i].attr.tracefile_count = uchan->tracefile_count;
357
358 /*
359 * Map enum lttng_ust_output to enum lttng_event_output.
360 */
361 switch (uchan->attr.output) {
362 case LTTNG_UST_MMAP:
363 channels[i].attr.output = LTTNG_EVENT_MMAP;
364 break;
365 default:
366 /*
367 * LTTNG_UST_MMAP is the only supported UST
368 * output mode.
369 */
370 assert(0);
371 break;
372 }
373
374 chan_exts[i].monitor_timer_interval =
375 uchan->monitor_timer_interval;
376 chan_exts[i].blocking_timeout =
377 uchan->attr.u.s.blocking_timeout;
378
379 ret = get_ust_runtime_stats(session, uchan,
380 &discarded_events, &lost_packets);
381 if (ret < 0) {
382 break;
383 }
384 chan_exts[i].discarded_events = discarded_events;
385 chan_exts[i].lost_packets = lost_packets;
386 i++;
387 }
388 rcu_read_unlock();
389 break;
390 }
391 default:
392 break;
393 }
394
395 end:
396 if (ret < 0) {
397 return -LTTNG_ERR_FATAL;
398 } else {
399 return LTTNG_OK;
400 }
401 }
402
403 static int increment_extended_len(const char *filter_expression,
404 struct lttng_event_exclusion *exclusion,
405 const struct lttng_userspace_probe_location *probe_location,
406 size_t *extended_len)
407 {
408 int ret = 0;
409
410 *extended_len += sizeof(struct lttcomm_event_extended_header);
411
412 if (filter_expression) {
413 *extended_len += strlen(filter_expression) + 1;
414 }
415
416 if (exclusion) {
417 *extended_len += exclusion->count * LTTNG_SYMBOL_NAME_LEN;
418 }
419
420 if (probe_location) {
421 ret = lttng_userspace_probe_location_serialize(probe_location,
422 NULL, NULL);
423 if (ret < 0) {
424 goto end;
425 }
426 *extended_len += ret;
427 }
428 ret = 0;
429 end:
430 return ret;
431 }
432
433 static int append_extended_info(const char *filter_expression,
434 struct lttng_event_exclusion *exclusion,
435 struct lttng_userspace_probe_location *probe_location,
436 void **extended_at)
437 {
438 int ret = 0;
439 size_t filter_len = 0;
440 size_t nb_exclusions = 0;
441 size_t userspace_probe_location_len = 0;
442 struct lttng_dynamic_buffer location_buffer;
443 struct lttcomm_event_extended_header extended_header;
444
445 if (filter_expression) {
446 filter_len = strlen(filter_expression) + 1;
447 }
448
449 if (exclusion) {
450 nb_exclusions = exclusion->count;
451 }
452
453 if (probe_location) {
454 lttng_dynamic_buffer_init(&location_buffer);
455 ret = lttng_userspace_probe_location_serialize(probe_location,
456 &location_buffer, NULL);
457 if (ret < 0) {
458 ret = -1;
459 goto end;
460 }
461 userspace_probe_location_len = location_buffer.size;
462 }
463
464 /* Set header fields */
465 extended_header.filter_len = filter_len;
466 extended_header.nb_exclusions = nb_exclusions;
467 extended_header.userspace_probe_location_len = userspace_probe_location_len;
468
469 /* Copy header */
470 memcpy(*extended_at, &extended_header, sizeof(extended_header));
471 *extended_at += sizeof(extended_header);
472
473 /* Copy filter string */
474 if (filter_expression) {
475 memcpy(*extended_at, filter_expression, filter_len);
476 *extended_at += filter_len;
477 }
478
479 /* Copy exclusion names */
480 if (exclusion) {
481 size_t len = nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
482
483 memcpy(*extended_at, &exclusion->names, len);
484 *extended_at += len;
485 }
486
487 if (probe_location) {
488 memcpy(*extended_at, location_buffer.data, location_buffer.size);
489 *extended_at += location_buffer.size;
490 lttng_dynamic_buffer_reset(&location_buffer);
491 }
492 ret = 0;
493 end:
494 return ret;
495 }
496
497 /*
498 * Create a list of agent domain events.
499 *
500 * Return number of events in list on success or else a negative value.
501 */
502 static int list_lttng_agent_events(struct agent *agt,
503 struct lttng_event **events, size_t *total_size)
504 {
505 int i = 0, ret = 0;
506 unsigned int nb_event = 0;
507 struct agent_event *event;
508 struct lttng_event *tmp_events = NULL;
509 struct lttng_ht_iter iter;
510 size_t extended_len = 0;
511 void *extended_at;
512
513 assert(agt);
514 assert(events);
515
516 DBG3("Listing agent events");
517
518 rcu_read_lock();
519 nb_event = lttng_ht_get_count(agt->events);
520 rcu_read_unlock();
521 if (nb_event == 0) {
522 ret = nb_event;
523 *total_size = 0;
524 goto error;
525 }
526
527 /* Compute required extended infos size */
528 extended_len = nb_event * sizeof(struct lttcomm_event_extended_header);
529
530 /*
531 * This is only valid because the commands which add events are
532 * processed in the same thread as the listing.
533 */
534 rcu_read_lock();
535 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
536 ret = increment_extended_len(event->filter_expression, NULL, NULL,
537 &extended_len);
538 if (ret) {
539 DBG("Error computing the length of extended info message");
540 ret = -LTTNG_ERR_FATAL;
541 goto error;
542 }
543 }
544 rcu_read_unlock();
545
546 *total_size = nb_event * sizeof(*tmp_events) + extended_len;
547 tmp_events = zmalloc(*total_size);
548 if (!tmp_events) {
549 PERROR("zmalloc agent events session");
550 ret = -LTTNG_ERR_FATAL;
551 goto error;
552 }
553
554 extended_at = ((uint8_t *) tmp_events) +
555 nb_event * sizeof(struct lttng_event);
556
557 rcu_read_lock();
558 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
559 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
560 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
561 tmp_events[i].enabled = event->enabled;
562 tmp_events[i].loglevel = event->loglevel_value;
563 tmp_events[i].loglevel_type = event->loglevel_type;
564 i++;
565
566 /* Append extended info */
567 ret = append_extended_info(event->filter_expression, NULL, NULL,
568 &extended_at);
569 if (ret) {
570 DBG("Error appending extended info message");
571 ret = -LTTNG_ERR_FATAL;
572 goto error;
573 }
574 }
575
576 *events = tmp_events;
577 ret = nb_event;
578 assert(nb_event == i);
579
580 end:
581 rcu_read_unlock();
582 return ret;
583 error:
584 free(tmp_events);
585 goto end;
586 }
587
588 /*
589 * Create a list of ust global domain events.
590 */
591 static int list_lttng_ust_global_events(char *channel_name,
592 struct ltt_ust_domain_global *ust_global,
593 struct lttng_event **events, size_t *total_size)
594 {
595 int i = 0, ret = 0;
596 unsigned int nb_event = 0;
597 struct lttng_ht_iter iter;
598 struct lttng_ht_node_str *node;
599 struct ltt_ust_channel *uchan;
600 struct ltt_ust_event *uevent;
601 struct lttng_event *tmp;
602 size_t extended_len = 0;
603 void *extended_at;
604
605 DBG("Listing UST global events for channel %s", channel_name);
606
607 rcu_read_lock();
608
609 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
610 node = lttng_ht_iter_get_node_str(&iter);
611 if (node == NULL) {
612 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
613 goto end;
614 }
615
616 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
617
618 nb_event = lttng_ht_get_count(uchan->events);
619 if (nb_event == 0) {
620 ret = nb_event;
621 *total_size = 0;
622 goto end;
623 }
624
625 DBG3("Listing UST global %d events", nb_event);
626
627 /* Compute required extended infos size */
628 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
629 if (uevent->internal) {
630 nb_event--;
631 continue;
632 }
633
634 ret = increment_extended_len(uevent->filter_expression,
635 uevent->exclusion, NULL, &extended_len);
636 if (ret) {
637 DBG("Error computing the length of extended info message");
638 ret = -LTTNG_ERR_FATAL;
639 goto end;
640 }
641 }
642 if (nb_event == 0) {
643 /* All events are internal, skip. */
644 ret = 0;
645 *total_size = 0;
646 goto end;
647 }
648
649 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
650 tmp = zmalloc(*total_size);
651 if (tmp == NULL) {
652 ret = -LTTNG_ERR_FATAL;
653 goto end;
654 }
655
656 extended_at = ((uint8_t *) tmp) + nb_event * sizeof(struct lttng_event);
657
658 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
659 if (uevent->internal) {
660 /* This event should remain hidden from clients */
661 continue;
662 }
663 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
664 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
665 tmp[i].enabled = uevent->enabled;
666
667 switch (uevent->attr.instrumentation) {
668 case LTTNG_UST_TRACEPOINT:
669 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
670 break;
671 case LTTNG_UST_PROBE:
672 tmp[i].type = LTTNG_EVENT_PROBE;
673 break;
674 case LTTNG_UST_FUNCTION:
675 tmp[i].type = LTTNG_EVENT_FUNCTION;
676 break;
677 }
678
679 tmp[i].loglevel = uevent->attr.loglevel;
680 switch (uevent->attr.loglevel_type) {
681 case LTTNG_UST_LOGLEVEL_ALL:
682 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
683 break;
684 case LTTNG_UST_LOGLEVEL_RANGE:
685 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
686 break;
687 case LTTNG_UST_LOGLEVEL_SINGLE:
688 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
689 break;
690 }
691 if (uevent->filter) {
692 tmp[i].filter = 1;
693 }
694 if (uevent->exclusion) {
695 tmp[i].exclusion = 1;
696 }
697 i++;
698
699 /* Append extended info */
700 ret = append_extended_info(uevent->filter_expression,
701 uevent->exclusion, NULL, &extended_at);
702 if (ret) {
703 DBG("Error appending extended info message");
704 ret = -LTTNG_ERR_FATAL;
705 goto end;
706 }
707 }
708
709 ret = nb_event;
710 *events = tmp;
711 end:
712 rcu_read_unlock();
713 return ret;
714 }
715
716 /*
717 * Fill lttng_event array of all kernel events in the channel.
718 */
719 static int list_lttng_kernel_events(char *channel_name,
720 struct ltt_kernel_session *kernel_session,
721 struct lttng_event **events, size_t *total_size)
722 {
723 int i = 0, ret;
724 unsigned int nb_event;
725 struct ltt_kernel_event *event;
726 struct ltt_kernel_channel *kchan;
727 size_t extended_len = 0;
728 void *extended_at;
729
730 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
731 if (kchan == NULL) {
732 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
733 goto error;
734 }
735
736 nb_event = kchan->event_count;
737
738 DBG("Listing events for channel %s", kchan->channel->name);
739
740 if (nb_event == 0) {
741 *total_size = 0;
742 *events = NULL;
743 goto end;
744 }
745
746 /* Compute required extended infos size */
747 cds_list_for_each_entry(event, &kchan->events_list.head, list) {
748 ret = increment_extended_len(event->filter_expression, NULL,
749 event->userspace_probe_location,
750 &extended_len);
751 if (ret) {
752 DBG("Error computing the length of extended info message");
753 ret = -LTTNG_ERR_FATAL;
754 goto error;
755 }
756 }
757
758 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
759 *events = zmalloc(*total_size);
760 if (*events == NULL) {
761 ret = -LTTNG_ERR_FATAL;
762 goto error;
763 }
764
765 extended_at = ((void *) *events) +
766 nb_event * sizeof(struct lttng_event);
767
768 /* Kernel channels */
769 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
770 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
771 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
772 (*events)[i].enabled = event->enabled;
773 (*events)[i].filter =
774 (unsigned char) !!event->filter_expression;
775
776 switch (event->event->instrumentation) {
777 case LTTNG_KERNEL_TRACEPOINT:
778 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
779 break;
780 case LTTNG_KERNEL_KRETPROBE:
781 (*events)[i].type = LTTNG_EVENT_FUNCTION;
782 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
783 sizeof(struct lttng_kernel_kprobe));
784 break;
785 case LTTNG_KERNEL_KPROBE:
786 (*events)[i].type = LTTNG_EVENT_PROBE;
787 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
788 sizeof(struct lttng_kernel_kprobe));
789 break;
790 case LTTNG_KERNEL_UPROBE:
791 (*events)[i].type = LTTNG_EVENT_USERSPACE_PROBE;
792 break;
793 case LTTNG_KERNEL_FUNCTION:
794 (*events)[i].type = LTTNG_EVENT_FUNCTION;
795 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
796 sizeof(struct lttng_kernel_function));
797 break;
798 case LTTNG_KERNEL_NOOP:
799 (*events)[i].type = LTTNG_EVENT_NOOP;
800 break;
801 case LTTNG_KERNEL_SYSCALL:
802 (*events)[i].type = LTTNG_EVENT_SYSCALL;
803 break;
804 case LTTNG_KERNEL_ALL:
805 /* fall-through. */
806 default:
807 assert(0);
808 break;
809 }
810 i++;
811
812 /* Append extended info */
813 ret = append_extended_info(event->filter_expression, NULL,
814 event->userspace_probe_location, &extended_at);
815 if (ret) {
816 DBG("Error appending extended info message");
817 ret = -LTTNG_ERR_FATAL;
818 goto error;
819 }
820 }
821
822 end:
823 return nb_event;
824
825 error:
826 /* Negate the error code to differentiate the size from an error */
827 return -ret;
828 }
829
830 /*
831 * Add URI so the consumer output object. Set the correct path depending on the
832 * domain adding the default trace directory.
833 */
834 static enum lttng_error_code add_uri_to_consumer(
835 const struct ltt_session *session,
836 struct consumer_output *consumer,
837 struct lttng_uri *uri, enum lttng_domain_type domain)
838 {
839 int ret;
840 enum lttng_error_code ret_code = LTTNG_OK;
841
842 assert(uri);
843
844 if (consumer == NULL) {
845 DBG("No consumer detected. Don't add URI. Stopping.");
846 ret_code = LTTNG_ERR_NO_CONSUMER;
847 goto error;
848 }
849
850 switch (domain) {
851 case LTTNG_DOMAIN_KERNEL:
852 ret = lttng_strncpy(consumer->domain_subdir,
853 DEFAULT_KERNEL_TRACE_DIR,
854 sizeof(consumer->domain_subdir));
855 break;
856 case LTTNG_DOMAIN_UST:
857 ret = lttng_strncpy(consumer->domain_subdir,
858 DEFAULT_UST_TRACE_DIR,
859 sizeof(consumer->domain_subdir));
860 break;
861 default:
862 /*
863 * This case is possible is we try to add the URI to the global
864 * tracing session consumer object which in this case there is
865 * no subdir.
866 */
867 memset(consumer->domain_subdir, 0,
868 sizeof(consumer->domain_subdir));
869 ret = 0;
870 }
871 if (ret) {
872 ERR("Failed to initialize consumer output domain subdirectory");
873 ret_code = LTTNG_ERR_FATAL;
874 goto error;
875 }
876
877 switch (uri->dtype) {
878 case LTTNG_DST_IPV4:
879 case LTTNG_DST_IPV6:
880 DBG2("Setting network URI to consumer");
881
882 if (consumer->type == CONSUMER_DST_NET) {
883 if ((uri->stype == LTTNG_STREAM_CONTROL &&
884 consumer->dst.net.control_isset) ||
885 (uri->stype == LTTNG_STREAM_DATA &&
886 consumer->dst.net.data_isset)) {
887 ret_code = LTTNG_ERR_URL_EXIST;
888 goto error;
889 }
890 } else {
891 memset(&consumer->dst, 0, sizeof(consumer->dst));
892 }
893
894 /* Set URI into consumer output object */
895 ret = consumer_set_network_uri(session, consumer, uri);
896 if (ret < 0) {
897 ret_code = -ret;
898 goto error;
899 } else if (ret == 1) {
900 /*
901 * URI was the same in the consumer so we do not append the subdir
902 * again so to not duplicate output dir.
903 */
904 ret_code = LTTNG_OK;
905 goto error;
906 }
907 break;
908 case LTTNG_DST_PATH:
909 if (*uri->dst.path != '/' || strstr(uri->dst.path, "../")) {
910 ret_code = LTTNG_ERR_INVALID;
911 goto error;
912 }
913 DBG2("Setting trace directory path from URI to %s",
914 uri->dst.path);
915 memset(&consumer->dst, 0, sizeof(consumer->dst));
916
917 ret = lttng_strncpy(consumer->dst.session_root_path,
918 uri->dst.path,
919 sizeof(consumer->dst.session_root_path));
920 if (ret) {
921 ret_code = LTTNG_ERR_FATAL;
922 goto error;
923 }
924 consumer->type = CONSUMER_DST_LOCAL;
925 break;
926 }
927
928 ret_code = LTTNG_OK;
929 error:
930 return ret_code;
931 }
932
933 /*
934 * Init tracing by creating trace directory and sending fds kernel consumer.
935 */
936 static int init_kernel_tracing(struct ltt_kernel_session *session)
937 {
938 int ret = 0;
939 struct lttng_ht_iter iter;
940 struct consumer_socket *socket;
941
942 assert(session);
943
944 rcu_read_lock();
945
946 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
947 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
948 socket, node.node) {
949 pthread_mutex_lock(socket->lock);
950 ret = kernel_consumer_send_session(socket, session);
951 pthread_mutex_unlock(socket->lock);
952 if (ret < 0) {
953 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
954 goto error;
955 }
956 }
957 }
958
959 error:
960 rcu_read_unlock();
961 return ret;
962 }
963
964 /*
965 * Create a socket to the relayd using the URI.
966 *
967 * On success, the relayd_sock pointer is set to the created socket.
968 * Else, it remains untouched and an LTTng error code is returned.
969 */
970 static enum lttng_error_code create_connect_relayd(struct lttng_uri *uri,
971 struct lttcomm_relayd_sock **relayd_sock,
972 struct consumer_output *consumer)
973 {
974 int ret;
975 enum lttng_error_code status = LTTNG_OK;
976 struct lttcomm_relayd_sock *rsock;
977
978 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
979 RELAYD_VERSION_COMM_MINOR);
980 if (!rsock) {
981 status = LTTNG_ERR_FATAL;
982 goto error;
983 }
984
985 /*
986 * Connect to relayd so we can proceed with a session creation. This call
987 * can possibly block for an arbitrary amount of time to set the health
988 * state to be in poll execution.
989 */
990 health_poll_entry();
991 ret = relayd_connect(rsock);
992 health_poll_exit();
993 if (ret < 0) {
994 ERR("Unable to reach lttng-relayd");
995 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
996 goto free_sock;
997 }
998
999 /* Create socket for control stream. */
1000 if (uri->stype == LTTNG_STREAM_CONTROL) {
1001 uint64_t result_flags;
1002
1003 DBG3("Creating relayd stream socket from URI");
1004
1005 /* Check relayd version */
1006 ret = relayd_version_check(rsock);
1007 if (ret == LTTNG_ERR_RELAYD_VERSION_FAIL) {
1008 status = LTTNG_ERR_RELAYD_VERSION_FAIL;
1009 goto close_sock;
1010 } else if (ret < 0) {
1011 ERR("Unable to reach lttng-relayd");
1012 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
1013 goto close_sock;
1014 }
1015 consumer->relay_major_version = rsock->major;
1016 consumer->relay_minor_version = rsock->minor;
1017 ret = relayd_get_configuration(rsock, 0,
1018 &result_flags);
1019 if (ret < 0) {
1020 ERR("Unable to get relayd configuration");
1021 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
1022 goto close_sock;
1023 }
1024 if (result_flags & LTTCOMM_RELAYD_CONFIGURATION_FLAG_CLEAR_ALLOWED) {
1025 consumer->relay_allows_clear = true;
1026 }
1027 } else if (uri->stype == LTTNG_STREAM_DATA) {
1028 DBG3("Creating relayd data socket from URI");
1029 } else {
1030 /* Command is not valid */
1031 ERR("Relayd invalid stream type: %d", uri->stype);
1032 status = LTTNG_ERR_INVALID;
1033 goto close_sock;
1034 }
1035
1036 *relayd_sock = rsock;
1037
1038 return status;
1039
1040 close_sock:
1041 /* The returned value is not useful since we are on an error path. */
1042 (void) relayd_close(rsock);
1043 free_sock:
1044 free(rsock);
1045 error:
1046 return status;
1047 }
1048
1049 /*
1050 * Connect to the relayd using URI and send the socket to the right consumer.
1051 *
1052 * The consumer socket lock must be held by the caller.
1053 *
1054 * Returns LTTNG_OK on success or an LTTng error code on failure.
1055 */
1056 static enum lttng_error_code send_consumer_relayd_socket(
1057 unsigned int session_id,
1058 struct lttng_uri *relayd_uri,
1059 struct consumer_output *consumer,
1060 struct consumer_socket *consumer_sock,
1061 const char *session_name, const char *hostname,
1062 const char *base_path, int session_live_timer,
1063 const uint64_t *current_chunk_id,
1064 time_t session_creation_time,
1065 bool session_name_contains_creation_time)
1066 {
1067 int ret;
1068 struct lttcomm_relayd_sock *rsock = NULL;
1069 enum lttng_error_code status;
1070
1071 /* Connect to relayd and make version check if uri is the control. */
1072 status = create_connect_relayd(relayd_uri, &rsock, consumer);
1073 if (status != LTTNG_OK) {
1074 goto relayd_comm_error;
1075 }
1076 assert(rsock);
1077
1078 /* Set the network sequence index if not set. */
1079 if (consumer->net_seq_index == (uint64_t) -1ULL) {
1080 pthread_mutex_lock(&relayd_net_seq_idx_lock);
1081 /*
1082 * Increment net_seq_idx because we are about to transfer the
1083 * new relayd socket to the consumer.
1084 * Assign unique key so the consumer can match streams.
1085 */
1086 consumer->net_seq_index = ++relayd_net_seq_idx;
1087 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
1088 }
1089
1090 /* Send relayd socket to consumer. */
1091 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
1092 relayd_uri->stype, session_id,
1093 session_name, hostname, base_path,
1094 session_live_timer, current_chunk_id,
1095 session_creation_time, session_name_contains_creation_time);
1096 if (ret < 0) {
1097 status = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
1098 goto close_sock;
1099 }
1100
1101 /* Flag that the corresponding socket was sent. */
1102 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
1103 consumer_sock->control_sock_sent = 1;
1104 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
1105 consumer_sock->data_sock_sent = 1;
1106 }
1107
1108 /*
1109 * Close socket which was dup on the consumer side. The session daemon does
1110 * NOT keep track of the relayd socket(s) once transfer to the consumer.
1111 */
1112
1113 close_sock:
1114 if (status != LTTNG_OK) {
1115 /*
1116 * The consumer output for this session should not be used anymore
1117 * since the relayd connection failed thus making any tracing or/and
1118 * streaming not usable.
1119 */
1120 consumer->enabled = 0;
1121 }
1122 (void) relayd_close(rsock);
1123 free(rsock);
1124
1125 relayd_comm_error:
1126 return status;
1127 }
1128
1129 /*
1130 * Send both relayd sockets to a specific consumer and domain. This is a
1131 * helper function to facilitate sending the information to the consumer for a
1132 * session.
1133 *
1134 * The consumer socket lock must be held by the caller.
1135 *
1136 * Returns LTTNG_OK, or an LTTng error code on failure.
1137 */
1138 static enum lttng_error_code send_consumer_relayd_sockets(
1139 enum lttng_domain_type domain,
1140 unsigned int session_id, struct consumer_output *consumer,
1141 struct consumer_socket *sock, const char *session_name,
1142 const char *hostname, const char *base_path, int session_live_timer,
1143 const uint64_t *current_chunk_id, time_t session_creation_time,
1144 bool session_name_contains_creation_time)
1145 {
1146 enum lttng_error_code status = LTTNG_OK;
1147
1148 assert(consumer);
1149 assert(sock);
1150
1151 /* Sending control relayd socket. */
1152 if (!sock->control_sock_sent) {
1153 status = send_consumer_relayd_socket(session_id,
1154 &consumer->dst.net.control, consumer, sock,
1155 session_name, hostname, base_path, session_live_timer,
1156 current_chunk_id, session_creation_time,
1157 session_name_contains_creation_time);
1158 if (status != LTTNG_OK) {
1159 goto error;
1160 }
1161 }
1162
1163 /* Sending data relayd socket. */
1164 if (!sock->data_sock_sent) {
1165 status = send_consumer_relayd_socket(session_id,
1166 &consumer->dst.net.data, consumer, sock,
1167 session_name, hostname, base_path, session_live_timer,
1168 current_chunk_id, session_creation_time,
1169 session_name_contains_creation_time);
1170 if (status != LTTNG_OK) {
1171 goto error;
1172 }
1173 }
1174
1175 error:
1176 return status;
1177 }
1178
1179 /*
1180 * Setup relayd connections for a tracing session. First creates the socket to
1181 * the relayd and send them to the right domain consumer. Consumer type MUST be
1182 * network.
1183 */
1184 int cmd_setup_relayd(struct ltt_session *session)
1185 {
1186 int ret = LTTNG_OK;
1187 struct ltt_ust_session *usess;
1188 struct ltt_kernel_session *ksess;
1189 struct consumer_socket *socket;
1190 struct lttng_ht_iter iter;
1191 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
1192
1193 assert(session);
1194
1195 usess = session->ust_session;
1196 ksess = session->kernel_session;
1197
1198 DBG("Setting relayd for session %s", session->name);
1199
1200 rcu_read_lock();
1201 if (session->current_trace_chunk) {
1202 enum lttng_trace_chunk_status status = lttng_trace_chunk_get_id(
1203 session->current_trace_chunk, &current_chunk_id.value);
1204
1205 if (status == LTTNG_TRACE_CHUNK_STATUS_OK) {
1206 current_chunk_id.is_set = true;
1207 } else {
1208 ERR("Failed to get current trace chunk id");
1209 ret = LTTNG_ERR_UNK;
1210 goto error;
1211 }
1212 }
1213
1214 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1215 && usess->consumer->enabled) {
1216 /* For each consumer socket, send relayd sockets */
1217 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1218 socket, node.node) {
1219 pthread_mutex_lock(socket->lock);
1220 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1221 usess->consumer, socket,
1222 session->name, session->hostname,
1223 session->base_path,
1224 session->live_timer,
1225 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1226 session->creation_time,
1227 session->name_contains_creation_time);
1228 pthread_mutex_unlock(socket->lock);
1229 if (ret != LTTNG_OK) {
1230 goto error;
1231 }
1232 /* Session is now ready for network streaming. */
1233 session->net_handle = 1;
1234 }
1235 session->consumer->relay_major_version =
1236 usess->consumer->relay_major_version;
1237 session->consumer->relay_minor_version =
1238 usess->consumer->relay_minor_version;
1239 session->consumer->relay_allows_clear =
1240 usess->consumer->relay_allows_clear;
1241 }
1242
1243 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1244 && ksess->consumer->enabled) {
1245 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1246 socket, node.node) {
1247 pthread_mutex_lock(socket->lock);
1248 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1249 ksess->consumer, socket,
1250 session->name, session->hostname,
1251 session->base_path,
1252 session->live_timer,
1253 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1254 session->creation_time,
1255 session->name_contains_creation_time);
1256 pthread_mutex_unlock(socket->lock);
1257 if (ret != LTTNG_OK) {
1258 goto error;
1259 }
1260 /* Session is now ready for network streaming. */
1261 session->net_handle = 1;
1262 }
1263 session->consumer->relay_major_version =
1264 ksess->consumer->relay_major_version;
1265 session->consumer->relay_minor_version =
1266 ksess->consumer->relay_minor_version;
1267 session->consumer->relay_allows_clear =
1268 ksess->consumer->relay_allows_clear;
1269 }
1270
1271 error:
1272 rcu_read_unlock();
1273 return ret;
1274 }
1275
1276 /*
1277 * Start a kernel session by opening all necessary streams.
1278 */
1279 int start_kernel_session(struct ltt_kernel_session *ksess)
1280 {
1281 int ret;
1282 struct ltt_kernel_channel *kchan;
1283
1284 /* Open kernel metadata */
1285 if (ksess->metadata == NULL && ksess->output_traces) {
1286 ret = kernel_open_metadata(ksess);
1287 if (ret < 0) {
1288 ret = LTTNG_ERR_KERN_META_FAIL;
1289 goto error;
1290 }
1291 }
1292
1293 /* Open kernel metadata stream */
1294 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1295 ret = kernel_open_metadata_stream(ksess);
1296 if (ret < 0) {
1297 ERR("Kernel create metadata stream failed");
1298 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1299 goto error;
1300 }
1301 }
1302
1303 /* For each channel */
1304 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1305 if (kchan->stream_count == 0) {
1306 ret = kernel_open_channel_stream(kchan);
1307 if (ret < 0) {
1308 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1309 goto error;
1310 }
1311 /* Update the stream global counter */
1312 ksess->stream_count_global += ret;
1313 }
1314 }
1315
1316 /* Setup kernel consumer socket and send fds to it */
1317 ret = init_kernel_tracing(ksess);
1318 if (ret != 0) {
1319 ret = LTTNG_ERR_KERN_START_FAIL;
1320 goto error;
1321 }
1322
1323 /* This start the kernel tracing */
1324 ret = kernel_start_session(ksess);
1325 if (ret < 0) {
1326 ret = LTTNG_ERR_KERN_START_FAIL;
1327 goto error;
1328 }
1329
1330 /* Quiescent wait after starting trace */
1331 kernel_wait_quiescent();
1332
1333 ksess->active = 1;
1334
1335 ret = LTTNG_OK;
1336
1337 error:
1338 return ret;
1339 }
1340
1341 int stop_kernel_session(struct ltt_kernel_session *ksess)
1342 {
1343 struct ltt_kernel_channel *kchan;
1344 bool error_occurred = false;
1345 int ret;
1346
1347 if (!ksess || !ksess->active) {
1348 return LTTNG_OK;
1349 }
1350 DBG("Stopping kernel tracing");
1351
1352 ret = kernel_stop_session(ksess);
1353 if (ret < 0) {
1354 ret = LTTNG_ERR_KERN_STOP_FAIL;
1355 goto error;
1356 }
1357
1358 kernel_wait_quiescent();
1359
1360 /* Flush metadata after stopping (if exists) */
1361 if (ksess->metadata_stream_fd >= 0) {
1362 ret = kernel_metadata_flush_buffer(ksess->metadata_stream_fd);
1363 if (ret < 0) {
1364 ERR("Kernel metadata flush failed");
1365 error_occurred = true;
1366 }
1367 }
1368
1369 /* Flush all buffers after stopping */
1370 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1371 ret = kernel_flush_buffer(kchan);
1372 if (ret < 0) {
1373 ERR("Kernel flush buffer error");
1374 error_occurred = true;
1375 }
1376 }
1377
1378 ksess->active = 0;
1379 if (error_occurred) {
1380 ret = LTTNG_ERR_UNK;
1381 } else {
1382 ret = LTTNG_OK;
1383 }
1384 error:
1385 return ret;
1386 }
1387
1388 /*
1389 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1390 */
1391 int cmd_disable_channel(struct ltt_session *session,
1392 enum lttng_domain_type domain, char *channel_name)
1393 {
1394 int ret;
1395 struct ltt_ust_session *usess;
1396
1397 usess = session->ust_session;
1398
1399 rcu_read_lock();
1400
1401 switch (domain) {
1402 case LTTNG_DOMAIN_KERNEL:
1403 {
1404 ret = channel_kernel_disable(session->kernel_session,
1405 channel_name);
1406 if (ret != LTTNG_OK) {
1407 goto error;
1408 }
1409
1410 kernel_wait_quiescent();
1411 break;
1412 }
1413 case LTTNG_DOMAIN_UST:
1414 {
1415 struct ltt_ust_channel *uchan;
1416 struct lttng_ht *chan_ht;
1417
1418 chan_ht = usess->domain_global.channels;
1419
1420 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1421 if (uchan == NULL) {
1422 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1423 goto error;
1424 }
1425
1426 ret = channel_ust_disable(usess, uchan);
1427 if (ret != LTTNG_OK) {
1428 goto error;
1429 }
1430 break;
1431 }
1432 default:
1433 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1434 goto error;
1435 }
1436
1437 ret = LTTNG_OK;
1438
1439 error:
1440 rcu_read_unlock();
1441 return ret;
1442 }
1443
1444 /*
1445 * Command LTTNG_TRACK_ID processed by the client thread.
1446 *
1447 * Called with session lock held.
1448 */
1449 int cmd_track_id(struct ltt_session *session,
1450 enum lttng_tracker_type tracker_type,
1451 enum lttng_domain_type domain,
1452 const struct lttng_tracker_id *id)
1453 {
1454 int ret;
1455
1456 rcu_read_lock();
1457
1458 switch (domain) {
1459 case LTTNG_DOMAIN_KERNEL:
1460 {
1461 struct ltt_kernel_session *ksess;
1462
1463 ksess = session->kernel_session;
1464
1465 ret = kernel_track_id(tracker_type, ksess, id);
1466 if (ret != LTTNG_OK) {
1467 goto error;
1468 }
1469
1470 kernel_wait_quiescent();
1471 break;
1472 }
1473 case LTTNG_DOMAIN_UST:
1474 {
1475 struct ltt_ust_session *usess;
1476
1477 usess = session->ust_session;
1478
1479 ret = trace_ust_track_id(tracker_type, usess, id);
1480 if (ret != LTTNG_OK) {
1481 goto error;
1482 }
1483 break;
1484 }
1485 default:
1486 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1487 goto error;
1488 }
1489
1490 ret = LTTNG_OK;
1491
1492 error:
1493 rcu_read_unlock();
1494 return ret;
1495 }
1496
1497 /*
1498 * Command LTTNG_UNTRACK_ID processed by the client thread.
1499 *
1500 * Called with session lock held.
1501 */
1502 int cmd_untrack_id(struct ltt_session *session,
1503 enum lttng_tracker_type tracker_type,
1504 enum lttng_domain_type domain,
1505 const struct lttng_tracker_id *id)
1506 {
1507 int ret;
1508
1509 rcu_read_lock();
1510
1511 switch (domain) {
1512 case LTTNG_DOMAIN_KERNEL:
1513 {
1514 struct ltt_kernel_session *ksess;
1515
1516 ksess = session->kernel_session;
1517
1518 ret = kernel_untrack_id(tracker_type, ksess, id);
1519 if (ret != LTTNG_OK) {
1520 goto error;
1521 }
1522
1523 kernel_wait_quiescent();
1524 break;
1525 }
1526 case LTTNG_DOMAIN_UST:
1527 {
1528 struct ltt_ust_session *usess;
1529
1530 usess = session->ust_session;
1531
1532 ret = trace_ust_untrack_id(tracker_type, usess, id);
1533 if (ret != LTTNG_OK) {
1534 goto error;
1535 }
1536 break;
1537 }
1538 default:
1539 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1540 goto error;
1541 }
1542
1543 ret = LTTNG_OK;
1544
1545 error:
1546 rcu_read_unlock();
1547 return ret;
1548 }
1549
1550 /*
1551 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1552 *
1553 * The wpipe arguments is used as a notifier for the kernel thread.
1554 */
1555 int cmd_enable_channel(struct ltt_session *session,
1556 const struct lttng_domain *domain, const struct lttng_channel *_attr, int wpipe)
1557 {
1558 int ret;
1559 struct ltt_ust_session *usess = session->ust_session;
1560 struct lttng_ht *chan_ht;
1561 size_t len;
1562 struct lttng_channel attr;
1563
1564 assert(session);
1565 assert(_attr);
1566 assert(domain);
1567
1568 attr = *_attr;
1569 len = lttng_strnlen(attr.name, sizeof(attr.name));
1570
1571 /* Validate channel name */
1572 if (attr.name[0] == '.' ||
1573 memchr(attr.name, '/', len) != NULL) {
1574 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1575 goto end;
1576 }
1577
1578 DBG("Enabling channel %s for session %s", attr.name, session->name);
1579
1580 rcu_read_lock();
1581
1582 /*
1583 * Don't try to enable a channel if the session has been started at
1584 * some point in time before. The tracer does not allow it.
1585 */
1586 if (session->has_been_started) {
1587 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1588 goto error;
1589 }
1590
1591 /*
1592 * If the session is a live session, remove the switch timer, the
1593 * live timer does the same thing but sends also synchronisation
1594 * beacons for inactive streams.
1595 */
1596 if (session->live_timer > 0) {
1597 attr.attr.live_timer_interval = session->live_timer;
1598 attr.attr.switch_timer_interval = 0;
1599 }
1600
1601 /* Check for feature support */
1602 switch (domain->type) {
1603 case LTTNG_DOMAIN_KERNEL:
1604 {
1605 if (kernel_supports_ring_buffer_snapshot_sample_positions() != 1) {
1606 /* Sampling position of buffer is not supported */
1607 WARN("Kernel tracer does not support buffer monitoring. "
1608 "Setting the monitor interval timer to 0 "
1609 "(disabled) for channel '%s' of session '%s'",
1610 attr.name, session->name);
1611 lttng_channel_set_monitor_timer_interval(&attr, 0);
1612 }
1613 break;
1614 }
1615 case LTTNG_DOMAIN_UST:
1616 break;
1617 case LTTNG_DOMAIN_JUL:
1618 case LTTNG_DOMAIN_LOG4J:
1619 case LTTNG_DOMAIN_PYTHON:
1620 if (!agent_tracing_is_enabled()) {
1621 DBG("Attempted to enable a channel in an agent domain but the agent thread is not running");
1622 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
1623 goto error;
1624 }
1625 break;
1626 default:
1627 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1628 goto error;
1629 }
1630
1631 switch (domain->type) {
1632 case LTTNG_DOMAIN_KERNEL:
1633 {
1634 struct ltt_kernel_channel *kchan;
1635
1636 kchan = trace_kernel_get_channel_by_name(attr.name,
1637 session->kernel_session);
1638 if (kchan == NULL) {
1639 if (session->snapshot.nb_output > 0 ||
1640 session->snapshot_mode) {
1641 /* Enforce mmap output for snapshot sessions. */
1642 attr.attr.output = LTTNG_EVENT_MMAP;
1643 }
1644 ret = channel_kernel_create(session->kernel_session, &attr, wpipe);
1645 if (attr.name[0] != '\0') {
1646 session->kernel_session->has_non_default_channel = 1;
1647 }
1648 } else {
1649 ret = channel_kernel_enable(session->kernel_session, kchan);
1650 }
1651
1652 if (ret != LTTNG_OK) {
1653 goto error;
1654 }
1655
1656 kernel_wait_quiescent();
1657 break;
1658 }
1659 case LTTNG_DOMAIN_UST:
1660 case LTTNG_DOMAIN_JUL:
1661 case LTTNG_DOMAIN_LOG4J:
1662 case LTTNG_DOMAIN_PYTHON:
1663 {
1664 struct ltt_ust_channel *uchan;
1665
1666 /*
1667 * FIXME
1668 *
1669 * Current agent implementation limitations force us to allow
1670 * only one channel at once in "agent" subdomains. Each
1671 * subdomain has a default channel name which must be strictly
1672 * adhered to.
1673 */
1674 if (domain->type == LTTNG_DOMAIN_JUL) {
1675 if (strncmp(attr.name, DEFAULT_JUL_CHANNEL_NAME,
1676 LTTNG_SYMBOL_NAME_LEN)) {
1677 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1678 goto error;
1679 }
1680 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1681 if (strncmp(attr.name, DEFAULT_LOG4J_CHANNEL_NAME,
1682 LTTNG_SYMBOL_NAME_LEN)) {
1683 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1684 goto error;
1685 }
1686 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1687 if (strncmp(attr.name, DEFAULT_PYTHON_CHANNEL_NAME,
1688 LTTNG_SYMBOL_NAME_LEN)) {
1689 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1690 goto error;
1691 }
1692 }
1693
1694 chan_ht = usess->domain_global.channels;
1695
1696 uchan = trace_ust_find_channel_by_name(chan_ht, attr.name);
1697 if (uchan == NULL) {
1698 ret = channel_ust_create(usess, &attr, domain->buf_type);
1699 if (attr.name[0] != '\0') {
1700 usess->has_non_default_channel = 1;
1701 }
1702 } else {
1703 ret = channel_ust_enable(usess, uchan);
1704 }
1705 break;
1706 }
1707 default:
1708 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1709 goto error;
1710 }
1711
1712 if (ret == LTTNG_OK && attr.attr.output != LTTNG_EVENT_MMAP) {
1713 session->has_non_mmap_channel = true;
1714 }
1715 error:
1716 rcu_read_unlock();
1717 end:
1718 return ret;
1719 }
1720
1721 /*
1722 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1723 */
1724 int cmd_disable_event(struct ltt_session *session,
1725 enum lttng_domain_type domain, const char *channel_name,
1726 const struct lttng_event *event)
1727 {
1728 int ret;
1729 const char *event_name;
1730
1731 DBG("Disable event command for event \'%s\'", event->name);
1732
1733 event_name = event->name;
1734
1735 /* Error out on unhandled search criteria */
1736 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1737 || event->pid || event->filter || event->exclusion) {
1738 ret = LTTNG_ERR_UNK;
1739 goto error;
1740 }
1741
1742 rcu_read_lock();
1743
1744 switch (domain) {
1745 case LTTNG_DOMAIN_KERNEL:
1746 {
1747 struct ltt_kernel_channel *kchan;
1748 struct ltt_kernel_session *ksess;
1749
1750 ksess = session->kernel_session;
1751
1752 /*
1753 * If a non-default channel has been created in the
1754 * session, explicitely require that -c chan_name needs
1755 * to be provided.
1756 */
1757 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1758 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1759 goto error_unlock;
1760 }
1761
1762 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1763 if (kchan == NULL) {
1764 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1765 goto error_unlock;
1766 }
1767
1768 switch (event->type) {
1769 case LTTNG_EVENT_ALL:
1770 case LTTNG_EVENT_TRACEPOINT:
1771 case LTTNG_EVENT_SYSCALL:
1772 case LTTNG_EVENT_PROBE:
1773 case LTTNG_EVENT_FUNCTION:
1774 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1775 if (event_name[0] == '\0') {
1776 ret = event_kernel_disable_event(kchan,
1777 NULL, event->type);
1778 } else {
1779 ret = event_kernel_disable_event(kchan,
1780 event_name, event->type);
1781 }
1782 if (ret != LTTNG_OK) {
1783 goto error_unlock;
1784 }
1785 break;
1786 default:
1787 ret = LTTNG_ERR_UNK;
1788 goto error_unlock;
1789 }
1790
1791 kernel_wait_quiescent();
1792 break;
1793 }
1794 case LTTNG_DOMAIN_UST:
1795 {
1796 struct ltt_ust_channel *uchan;
1797 struct ltt_ust_session *usess;
1798
1799 usess = session->ust_session;
1800
1801 if (validate_ust_event_name(event_name)) {
1802 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1803 goto error_unlock;
1804 }
1805
1806 /*
1807 * If a non-default channel has been created in the
1808 * session, explicitly require that -c chan_name needs
1809 * to be provided.
1810 */
1811 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1812 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1813 goto error_unlock;
1814 }
1815
1816 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1817 channel_name);
1818 if (uchan == NULL) {
1819 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1820 goto error_unlock;
1821 }
1822
1823 switch (event->type) {
1824 case LTTNG_EVENT_ALL:
1825 /*
1826 * An empty event name means that everything
1827 * should be disabled.
1828 */
1829 if (event->name[0] == '\0') {
1830 ret = event_ust_disable_all_tracepoints(usess, uchan);
1831 } else {
1832 ret = event_ust_disable_tracepoint(usess, uchan,
1833 event_name);
1834 }
1835 if (ret != LTTNG_OK) {
1836 goto error_unlock;
1837 }
1838 break;
1839 default:
1840 ret = LTTNG_ERR_UNK;
1841 goto error_unlock;
1842 }
1843
1844 DBG3("Disable UST event %s in channel %s completed", event_name,
1845 channel_name);
1846 break;
1847 }
1848 case LTTNG_DOMAIN_LOG4J:
1849 case LTTNG_DOMAIN_JUL:
1850 case LTTNG_DOMAIN_PYTHON:
1851 {
1852 struct agent *agt;
1853 struct ltt_ust_session *usess = session->ust_session;
1854
1855 assert(usess);
1856
1857 switch (event->type) {
1858 case LTTNG_EVENT_ALL:
1859 break;
1860 default:
1861 ret = LTTNG_ERR_UNK;
1862 goto error_unlock;
1863 }
1864
1865 agt = trace_ust_find_agent(usess, domain);
1866 if (!agt) {
1867 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1868 goto error_unlock;
1869 }
1870 /*
1871 * An empty event name means that everything
1872 * should be disabled.
1873 */
1874 if (event->name[0] == '\0') {
1875 ret = event_agent_disable_all(usess, agt);
1876 } else {
1877 ret = event_agent_disable(usess, agt, event_name);
1878 }
1879 if (ret != LTTNG_OK) {
1880 goto error_unlock;
1881 }
1882
1883 break;
1884 }
1885 default:
1886 ret = LTTNG_ERR_UND;
1887 goto error_unlock;
1888 }
1889
1890 ret = LTTNG_OK;
1891
1892 error_unlock:
1893 rcu_read_unlock();
1894 error:
1895 return ret;
1896 }
1897
1898 /*
1899 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1900 */
1901 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1902 char *channel_name, const struct lttng_event_context *ctx, int kwpipe)
1903 {
1904 int ret, chan_kern_created = 0, chan_ust_created = 0;
1905 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1906
1907 /*
1908 * Don't try to add a context if the session has been started at
1909 * some point in time before. The tracer does not allow it and would
1910 * result in a corrupted trace.
1911 */
1912 if (session->has_been_started) {
1913 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1914 goto end;
1915 }
1916
1917 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1918 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1919 app_ctx_name = ctx->u.app_ctx.ctx_name;
1920 }
1921
1922 switch (domain) {
1923 case LTTNG_DOMAIN_KERNEL:
1924 assert(session->kernel_session);
1925
1926 if (session->kernel_session->channel_count == 0) {
1927 /* Create default channel */
1928 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1929 if (ret != LTTNG_OK) {
1930 goto error;
1931 }
1932 chan_kern_created = 1;
1933 }
1934 /* Add kernel context to kernel tracer */
1935 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1936 if (ret != LTTNG_OK) {
1937 goto error;
1938 }
1939 break;
1940 case LTTNG_DOMAIN_JUL:
1941 case LTTNG_DOMAIN_LOG4J:
1942 {
1943 /*
1944 * Validate channel name.
1945 * If no channel name is given and the domain is JUL or LOG4J,
1946 * set it to the appropriate domain-specific channel name. If
1947 * a name is provided but does not match the expexted channel
1948 * name, return an error.
1949 */
1950 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1951 strcmp(channel_name,
1952 DEFAULT_JUL_CHANNEL_NAME)) {
1953 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1954 goto error;
1955 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1956 strcmp(channel_name,
1957 DEFAULT_LOG4J_CHANNEL_NAME)) {
1958 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1959 goto error;
1960 }
1961 /* break is _not_ missing here. */
1962 }
1963 case LTTNG_DOMAIN_UST:
1964 {
1965 struct ltt_ust_session *usess = session->ust_session;
1966 unsigned int chan_count;
1967
1968 assert(usess);
1969
1970 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1971 if (chan_count == 0) {
1972 struct lttng_channel *attr;
1973 /* Create default channel */
1974 attr = channel_new_default_attr(domain, usess->buffer_type);
1975 if (attr == NULL) {
1976 ret = LTTNG_ERR_FATAL;
1977 goto error;
1978 }
1979
1980 ret = channel_ust_create(usess, attr, usess->buffer_type);
1981 if (ret != LTTNG_OK) {
1982 free(attr);
1983 goto error;
1984 }
1985 channel_attr_destroy(attr);
1986 chan_ust_created = 1;
1987 }
1988
1989 ret = context_ust_add(usess, domain, ctx, channel_name);
1990 free(app_ctx_provider_name);
1991 free(app_ctx_name);
1992 app_ctx_name = NULL;
1993 app_ctx_provider_name = NULL;
1994 if (ret != LTTNG_OK) {
1995 goto error;
1996 }
1997 break;
1998 }
1999 default:
2000 ret = LTTNG_ERR_UND;
2001 goto error;
2002 }
2003
2004 ret = LTTNG_OK;
2005 goto end;
2006
2007 error:
2008 if (chan_kern_created) {
2009 struct ltt_kernel_channel *kchan =
2010 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
2011 session->kernel_session);
2012 /* Created previously, this should NOT fail. */
2013 assert(kchan);
2014 kernel_destroy_channel(kchan);
2015 }
2016
2017 if (chan_ust_created) {
2018 struct ltt_ust_channel *uchan =
2019 trace_ust_find_channel_by_name(
2020 session->ust_session->domain_global.channels,
2021 DEFAULT_CHANNEL_NAME);
2022 /* Created previously, this should NOT fail. */
2023 assert(uchan);
2024 /* Remove from the channel list of the session. */
2025 trace_ust_delete_channel(session->ust_session->domain_global.channels,
2026 uchan);
2027 trace_ust_destroy_channel(uchan);
2028 }
2029 end:
2030 free(app_ctx_provider_name);
2031 free(app_ctx_name);
2032 return ret;
2033 }
2034
2035 static inline bool name_starts_with(const char *name, const char *prefix)
2036 {
2037 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
2038
2039 return !strncmp(name, prefix, max_cmp_len);
2040 }
2041
2042 /* Perform userspace-specific event name validation */
2043 static int validate_ust_event_name(const char *name)
2044 {
2045 int ret = 0;
2046
2047 if (!name) {
2048 ret = -1;
2049 goto end;
2050 }
2051
2052 /*
2053 * Check name against all internal UST event component namespaces used
2054 * by the agents.
2055 */
2056 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
2057 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
2058 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
2059 ret = -1;
2060 }
2061
2062 end:
2063 return ret;
2064 }
2065
2066 /*
2067 * Internal version of cmd_enable_event() with a supplemental
2068 * "internal_event" flag which is used to enable internal events which should
2069 * be hidden from clients. Such events are used in the agent implementation to
2070 * enable the events through which all "agent" events are funeled.
2071 */
2072 static int _cmd_enable_event(struct ltt_session *session,
2073 const struct lttng_domain *domain,
2074 char *channel_name, struct lttng_event *event,
2075 char *filter_expression,
2076 struct lttng_filter_bytecode *filter,
2077 struct lttng_event_exclusion *exclusion,
2078 int wpipe, bool internal_event)
2079 {
2080 int ret = 0, channel_created = 0;
2081 struct lttng_channel *attr = NULL;
2082
2083 assert(session);
2084 assert(event);
2085 assert(channel_name);
2086
2087 /* If we have a filter, we must have its filter expression */
2088 assert(!(!!filter_expression ^ !!filter));
2089
2090 /* Normalize event name as a globbing pattern */
2091 strutils_normalize_star_glob_pattern(event->name);
2092
2093 /* Normalize exclusion names as globbing patterns */
2094 if (exclusion) {
2095 size_t i;
2096
2097 for (i = 0; i < exclusion->count; i++) {
2098 char *name = LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
2099
2100 strutils_normalize_star_glob_pattern(name);
2101 }
2102 }
2103
2104 DBG("Enable event command for event \'%s\'", event->name);
2105
2106 rcu_read_lock();
2107
2108 switch (domain->type) {
2109 case LTTNG_DOMAIN_KERNEL:
2110 {
2111 struct ltt_kernel_channel *kchan;
2112
2113 /*
2114 * If a non-default channel has been created in the
2115 * session, explicitely require that -c chan_name needs
2116 * to be provided.
2117 */
2118 if (session->kernel_session->has_non_default_channel
2119 && channel_name[0] == '\0') {
2120 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2121 goto error;
2122 }
2123
2124 kchan = trace_kernel_get_channel_by_name(channel_name,
2125 session->kernel_session);
2126 if (kchan == NULL) {
2127 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
2128 LTTNG_BUFFER_GLOBAL);
2129 if (attr == NULL) {
2130 ret = LTTNG_ERR_FATAL;
2131 goto error;
2132 }
2133 if (lttng_strncpy(attr->name, channel_name,
2134 sizeof(attr->name))) {
2135 ret = LTTNG_ERR_INVALID;
2136 goto error;
2137 }
2138
2139 ret = cmd_enable_channel(session, domain, attr, wpipe);
2140 if (ret != LTTNG_OK) {
2141 goto error;
2142 }
2143 channel_created = 1;
2144 }
2145
2146 /* Get the newly created kernel channel pointer */
2147 kchan = trace_kernel_get_channel_by_name(channel_name,
2148 session->kernel_session);
2149 if (kchan == NULL) {
2150 /* This sould not happen... */
2151 ret = LTTNG_ERR_FATAL;
2152 goto error;
2153 }
2154
2155 switch (event->type) {
2156 case LTTNG_EVENT_ALL:
2157 {
2158 char *filter_expression_a = NULL;
2159 struct lttng_filter_bytecode *filter_a = NULL;
2160
2161 /*
2162 * We need to duplicate filter_expression and filter,
2163 * because ownership is passed to first enable
2164 * event.
2165 */
2166 if (filter_expression) {
2167 filter_expression_a = strdup(filter_expression);
2168 if (!filter_expression_a) {
2169 ret = LTTNG_ERR_FATAL;
2170 goto error;
2171 }
2172 }
2173 if (filter) {
2174 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
2175 if (!filter_a) {
2176 free(filter_expression_a);
2177 ret = LTTNG_ERR_FATAL;
2178 goto error;
2179 }
2180 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
2181 }
2182 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
2183 ret = event_kernel_enable_event(kchan, event,
2184 filter_expression, filter);
2185 /* We have passed ownership */
2186 filter_expression = NULL;
2187 filter = NULL;
2188 if (ret != LTTNG_OK) {
2189 if (channel_created) {
2190 /* Let's not leak a useless channel. */
2191 kernel_destroy_channel(kchan);
2192 }
2193 free(filter_expression_a);
2194 free(filter_a);
2195 goto error;
2196 }
2197 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
2198 ret = event_kernel_enable_event(kchan, event,
2199 filter_expression_a, filter_a);
2200 /* We have passed ownership */
2201 filter_expression_a = NULL;
2202 filter_a = NULL;
2203 if (ret != LTTNG_OK) {
2204 goto error;
2205 }
2206 break;
2207 }
2208 case LTTNG_EVENT_PROBE:
2209 case LTTNG_EVENT_USERSPACE_PROBE:
2210 case LTTNG_EVENT_FUNCTION:
2211 case LTTNG_EVENT_FUNCTION_ENTRY:
2212 case LTTNG_EVENT_TRACEPOINT:
2213 ret = event_kernel_enable_event(kchan, event,
2214 filter_expression, filter);
2215 /* We have passed ownership */
2216 filter_expression = NULL;
2217 filter = NULL;
2218 if (ret != LTTNG_OK) {
2219 if (channel_created) {
2220 /* Let's not leak a useless channel. */
2221 kernel_destroy_channel(kchan);
2222 }
2223 goto error;
2224 }
2225 break;
2226 case LTTNG_EVENT_SYSCALL:
2227 ret = event_kernel_enable_event(kchan, event,
2228 filter_expression, filter);
2229 /* We have passed ownership */
2230 filter_expression = NULL;
2231 filter = NULL;
2232 if (ret != LTTNG_OK) {
2233 goto error;
2234 }
2235 break;
2236 default:
2237 ret = LTTNG_ERR_UNK;
2238 goto error;
2239 }
2240
2241 kernel_wait_quiescent();
2242 break;
2243 }
2244 case LTTNG_DOMAIN_UST:
2245 {
2246 struct ltt_ust_channel *uchan;
2247 struct ltt_ust_session *usess = session->ust_session;
2248
2249 assert(usess);
2250
2251 /*
2252 * If a non-default channel has been created in the
2253 * session, explicitely require that -c chan_name needs
2254 * to be provided.
2255 */
2256 if (usess->has_non_default_channel && channel_name[0] == '\0') {
2257 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2258 goto error;
2259 }
2260
2261 /* Get channel from global UST domain */
2262 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2263 channel_name);
2264 if (uchan == NULL) {
2265 /* Create default channel */
2266 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
2267 usess->buffer_type);
2268 if (attr == NULL) {
2269 ret = LTTNG_ERR_FATAL;
2270 goto error;
2271 }
2272 if (lttng_strncpy(attr->name, channel_name,
2273 sizeof(attr->name))) {
2274 ret = LTTNG_ERR_INVALID;
2275 goto error;
2276 }
2277
2278 ret = cmd_enable_channel(session, domain, attr, wpipe);
2279 if (ret != LTTNG_OK) {
2280 goto error;
2281 }
2282
2283 /* Get the newly created channel reference back */
2284 uchan = trace_ust_find_channel_by_name(
2285 usess->domain_global.channels, channel_name);
2286 assert(uchan);
2287 }
2288
2289 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2290 /*
2291 * Don't allow users to add UST events to channels which
2292 * are assigned to a userspace subdomain (JUL, Log4J,
2293 * Python, etc.).
2294 */
2295 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2296 goto error;
2297 }
2298
2299 if (!internal_event) {
2300 /*
2301 * Ensure the event name is not reserved for internal
2302 * use.
2303 */
2304 ret = validate_ust_event_name(event->name);
2305 if (ret) {
2306 WARN("Userspace event name %s failed validation.",
2307 event->name);
2308 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2309 goto error;
2310 }
2311 }
2312
2313 /* At this point, the session and channel exist on the tracer */
2314 ret = event_ust_enable_tracepoint(usess, uchan, event,
2315 filter_expression, filter, exclusion,
2316 internal_event);
2317 /* We have passed ownership */
2318 filter_expression = NULL;
2319 filter = NULL;
2320 exclusion = NULL;
2321 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2322 goto already_enabled;
2323 } else if (ret != LTTNG_OK) {
2324 goto error;
2325 }
2326 break;
2327 }
2328 case LTTNG_DOMAIN_LOG4J:
2329 case LTTNG_DOMAIN_JUL:
2330 case LTTNG_DOMAIN_PYTHON:
2331 {
2332 const char *default_event_name, *default_chan_name;
2333 struct agent *agt;
2334 struct lttng_event uevent;
2335 struct lttng_domain tmp_dom;
2336 struct ltt_ust_session *usess = session->ust_session;
2337
2338 assert(usess);
2339
2340 if (!agent_tracing_is_enabled()) {
2341 DBG("Attempted to enable an event in an agent domain but the agent thread is not running");
2342 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
2343 goto error;
2344 }
2345
2346 agt = trace_ust_find_agent(usess, domain->type);
2347 if (!agt) {
2348 agt = agent_create(domain->type);
2349 if (!agt) {
2350 ret = LTTNG_ERR_NOMEM;
2351 goto error;
2352 }
2353 agent_add(agt, usess->agents);
2354 }
2355
2356 /* Create the default tracepoint. */
2357 memset(&uevent, 0, sizeof(uevent));
2358 uevent.type = LTTNG_EVENT_TRACEPOINT;
2359 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2360 default_event_name = event_get_default_agent_ust_name(
2361 domain->type);
2362 if (!default_event_name) {
2363 ret = LTTNG_ERR_FATAL;
2364 goto error;
2365 }
2366 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2367 uevent.name[sizeof(uevent.name) - 1] = '\0';
2368
2369 /*
2370 * The domain type is changed because we are about to enable the
2371 * default channel and event for the JUL domain that are hardcoded.
2372 * This happens in the UST domain.
2373 */
2374 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2375 tmp_dom.type = LTTNG_DOMAIN_UST;
2376
2377 switch (domain->type) {
2378 case LTTNG_DOMAIN_LOG4J:
2379 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2380 break;
2381 case LTTNG_DOMAIN_JUL:
2382 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2383 break;
2384 case LTTNG_DOMAIN_PYTHON:
2385 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2386 break;
2387 default:
2388 /* The switch/case we are in makes this impossible */
2389 assert(0);
2390 }
2391
2392 {
2393 char *filter_expression_copy = NULL;
2394 struct lttng_filter_bytecode *filter_copy = NULL;
2395
2396 if (filter) {
2397 const size_t filter_size = sizeof(
2398 struct lttng_filter_bytecode)
2399 + filter->len;
2400
2401 filter_copy = zmalloc(filter_size);
2402 if (!filter_copy) {
2403 ret = LTTNG_ERR_NOMEM;
2404 goto error;
2405 }
2406 memcpy(filter_copy, filter, filter_size);
2407
2408 filter_expression_copy =
2409 strdup(filter_expression);
2410 if (!filter_expression) {
2411 ret = LTTNG_ERR_NOMEM;
2412 }
2413
2414 if (!filter_expression_copy || !filter_copy) {
2415 free(filter_expression_copy);
2416 free(filter_copy);
2417 goto error;
2418 }
2419 }
2420
2421 ret = cmd_enable_event_internal(session, &tmp_dom,
2422 (char *) default_chan_name,
2423 &uevent, filter_expression_copy,
2424 filter_copy, NULL, wpipe);
2425 }
2426
2427 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2428 goto already_enabled;
2429 } else if (ret != LTTNG_OK) {
2430 goto error;
2431 }
2432
2433 /* The wild card * means that everything should be enabled. */
2434 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2435 ret = event_agent_enable_all(usess, agt, event, filter,
2436 filter_expression);
2437 } else {
2438 ret = event_agent_enable(usess, agt, event, filter,
2439 filter_expression);
2440 }
2441 filter = NULL;
2442 filter_expression = NULL;
2443 if (ret != LTTNG_OK) {
2444 goto error;
2445 }
2446
2447 break;
2448 }
2449 default:
2450 ret = LTTNG_ERR_UND;
2451 goto error;
2452 }
2453
2454 ret = LTTNG_OK;
2455
2456 already_enabled:
2457 error:
2458 free(filter_expression);
2459 free(filter);
2460 free(exclusion);
2461 channel_attr_destroy(attr);
2462 rcu_read_unlock();
2463 return ret;
2464 }
2465
2466 /*
2467 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2468 * We own filter, exclusion, and filter_expression.
2469 */
2470 int cmd_enable_event(struct ltt_session *session,
2471 const struct lttng_domain *domain,
2472 char *channel_name, struct lttng_event *event,
2473 char *filter_expression,
2474 struct lttng_filter_bytecode *filter,
2475 struct lttng_event_exclusion *exclusion,
2476 int wpipe)
2477 {
2478 return _cmd_enable_event(session, domain, channel_name, event,
2479 filter_expression, filter, exclusion, wpipe, false);
2480 }
2481
2482 /*
2483 * Enable an event which is internal to LTTng. An internal should
2484 * never be made visible to clients and are immune to checks such as
2485 * reserved names.
2486 */
2487 static int cmd_enable_event_internal(struct ltt_session *session,
2488 const struct lttng_domain *domain,
2489 char *channel_name, struct lttng_event *event,
2490 char *filter_expression,
2491 struct lttng_filter_bytecode *filter,
2492 struct lttng_event_exclusion *exclusion,
2493 int wpipe)
2494 {
2495 return _cmd_enable_event(session, domain, channel_name, event,
2496 filter_expression, filter, exclusion, wpipe, true);
2497 }
2498
2499 /*
2500 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2501 */
2502 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2503 struct lttng_event **events)
2504 {
2505 int ret;
2506 ssize_t nb_events = 0;
2507
2508 switch (domain) {
2509 case LTTNG_DOMAIN_KERNEL:
2510 nb_events = kernel_list_events(events);
2511 if (nb_events < 0) {
2512 ret = LTTNG_ERR_KERN_LIST_FAIL;
2513 goto error;
2514 }
2515 break;
2516 case LTTNG_DOMAIN_UST:
2517 nb_events = ust_app_list_events(events);
2518 if (nb_events < 0) {
2519 ret = LTTNG_ERR_UST_LIST_FAIL;
2520 goto error;
2521 }
2522 break;
2523 case LTTNG_DOMAIN_LOG4J:
2524 case LTTNG_DOMAIN_JUL:
2525 case LTTNG_DOMAIN_PYTHON:
2526 nb_events = agent_list_events(events, domain);
2527 if (nb_events < 0) {
2528 ret = LTTNG_ERR_UST_LIST_FAIL;
2529 goto error;
2530 }
2531 break;
2532 default:
2533 ret = LTTNG_ERR_UND;
2534 goto error;
2535 }
2536
2537 return nb_events;
2538
2539 error:
2540 /* Return negative value to differentiate return code */
2541 return -ret;
2542 }
2543
2544 /*
2545 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2546 */
2547 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2548 struct lttng_event_field **fields)
2549 {
2550 int ret;
2551 ssize_t nb_fields = 0;
2552
2553 switch (domain) {
2554 case LTTNG_DOMAIN_UST:
2555 nb_fields = ust_app_list_event_fields(fields);
2556 if (nb_fields < 0) {
2557 ret = LTTNG_ERR_UST_LIST_FAIL;
2558 goto error;
2559 }
2560 break;
2561 case LTTNG_DOMAIN_KERNEL:
2562 default: /* fall-through */
2563 ret = LTTNG_ERR_UND;
2564 goto error;
2565 }
2566
2567 return nb_fields;
2568
2569 error:
2570 /* Return negative value to differentiate return code */
2571 return -ret;
2572 }
2573
2574 ssize_t cmd_list_syscalls(struct lttng_event **events)
2575 {
2576 return syscall_table_list(events);
2577 }
2578
2579 /*
2580 * Command LTTNG_LIST_TRACKER_IDS processed by the client thread.
2581 *
2582 * Called with session lock held.
2583 */
2584 int cmd_list_tracker_ids(enum lttng_tracker_type tracker_type,
2585 struct ltt_session *session,
2586 enum lttng_domain_type domain,
2587 struct lttng_tracker_ids **ids)
2588 {
2589 int ret = LTTNG_OK;
2590
2591 switch (domain) {
2592 case LTTNG_DOMAIN_KERNEL:
2593 {
2594 struct ltt_kernel_session *ksess;
2595
2596 ksess = session->kernel_session;
2597 ret = kernel_list_tracker_ids(tracker_type, ksess, ids);
2598 if (ret != LTTNG_OK) {
2599 ret = -LTTNG_ERR_KERN_LIST_FAIL;
2600 goto error;
2601 }
2602 break;
2603 }
2604 case LTTNG_DOMAIN_UST:
2605 {
2606 struct ltt_ust_session *usess;
2607
2608 usess = session->ust_session;
2609 ret = trace_ust_list_tracker_ids(tracker_type, usess, ids);
2610 if (ret != LTTNG_OK) {
2611 ret = -LTTNG_ERR_UST_LIST_FAIL;
2612 goto error;
2613 }
2614 break;
2615 }
2616 case LTTNG_DOMAIN_LOG4J:
2617 case LTTNG_DOMAIN_JUL:
2618 case LTTNG_DOMAIN_PYTHON:
2619 default:
2620 ret = -LTTNG_ERR_UND;
2621 goto error;
2622 }
2623
2624 error:
2625 /* Return negative value to differentiate return code */
2626 return ret;
2627 }
2628
2629 /*
2630 * Command LTTNG_START_TRACE processed by the client thread.
2631 *
2632 * Called with session mutex held.
2633 */
2634 int cmd_start_trace(struct ltt_session *session)
2635 {
2636 enum lttng_error_code ret;
2637 unsigned long nb_chan = 0;
2638 struct ltt_kernel_session *ksession;
2639 struct ltt_ust_session *usess;
2640 const bool session_rotated_after_last_stop =
2641 session->rotated_after_last_stop;
2642 const bool session_cleared_after_last_stop =
2643 session->cleared_after_last_stop;
2644
2645 assert(session);
2646
2647 /* Ease our life a bit ;) */
2648 ksession = session->kernel_session;
2649 usess = session->ust_session;
2650
2651 /* Is the session already started? */
2652 if (session->active) {
2653 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2654 /* Perform nothing */
2655 goto end;
2656 }
2657
2658 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING &&
2659 !session->current_trace_chunk) {
2660 /*
2661 * A rotation was launched while the session was stopped and
2662 * it has not been completed yet. It is not possible to start
2663 * the session since starting the session here would require a
2664 * rotation from "NULL" to a new trace chunk. That rotation
2665 * would overlap with the ongoing rotation, which is not
2666 * supported.
2667 */
2668 WARN("Refusing to start session \"%s\" as a rotation launched after the last \"stop\" is still ongoing",
2669 session->name);
2670 ret = LTTNG_ERR_ROTATION_PENDING;
2671 goto error;
2672 }
2673
2674 /*
2675 * Starting a session without channel is useless since after that it's not
2676 * possible to enable channel thus inform the client.
2677 */
2678 if (usess && usess->domain_global.channels) {
2679 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2680 }
2681 if (ksession) {
2682 nb_chan += ksession->channel_count;
2683 }
2684 if (!nb_chan) {
2685 ret = LTTNG_ERR_NO_CHANNEL;
2686 goto error;
2687 }
2688
2689 session->active = 1;
2690 session->rotated_after_last_stop = false;
2691 session->cleared_after_last_stop = false;
2692 if (session->output_traces && !session->current_trace_chunk) {
2693 if (!session->has_been_started) {
2694 struct lttng_trace_chunk *trace_chunk;
2695
2696 DBG("Creating initial trace chunk of session \"%s\"",
2697 session->name);
2698 trace_chunk = session_create_new_trace_chunk(
2699 session, NULL, NULL, NULL);
2700 if (!trace_chunk) {
2701 ret = LTTNG_ERR_CREATE_DIR_FAIL;
2702 goto error;
2703 }
2704 assert(!session->current_trace_chunk);
2705 ret = session_set_trace_chunk(session, trace_chunk,
2706 NULL);
2707 lttng_trace_chunk_put(trace_chunk);
2708 if (ret) {
2709 ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
2710 goto error;
2711 }
2712 } else {
2713 DBG("Rotating session \"%s\" from its current \"NULL\" trace chunk to a new chunk",
2714 session->name);
2715 /*
2716 * Rotate existing streams into the new chunk.
2717 * This is a "quiet" rotation has no client has
2718 * explicitly requested this operation.
2719 *
2720 * There is also no need to wait for the rotation
2721 * to complete as it will happen immediately. No data
2722 * was produced as the session was stopped, so the
2723 * rotation should happen on reception of the command.
2724 */
2725 ret = cmd_rotate_session(session, NULL, true,
2726 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
2727 if (ret != LTTNG_OK) {
2728 goto error;
2729 }
2730 }
2731 }
2732
2733 /* Kernel tracing */
2734 if (ksession != NULL) {
2735 DBG("Start kernel tracing session %s", session->name);
2736 ret = start_kernel_session(ksession);
2737 if (ret != LTTNG_OK) {
2738 goto error;
2739 }
2740 }
2741
2742 /* Flag session that trace should start automatically */
2743 if (usess) {
2744 int int_ret = ust_app_start_trace_all(usess);
2745
2746 if (int_ret < 0) {
2747 ret = LTTNG_ERR_UST_START_FAIL;
2748 goto error;
2749 }
2750 }
2751
2752 /*
2753 * Clear the flag that indicates that a rotation was done while the
2754 * session was stopped.
2755 */
2756 session->rotated_after_last_stop = false;
2757
2758 if (session->rotate_timer_period) {
2759 int int_ret = timer_session_rotation_schedule_timer_start(
2760 session, session->rotate_timer_period);
2761
2762 if (int_ret < 0) {
2763 ERR("Failed to enable rotate timer");
2764 ret = LTTNG_ERR_UNK;
2765 goto error;
2766 }
2767 }
2768
2769 ret = LTTNG_OK;
2770
2771 error:
2772 if (ret == LTTNG_OK) {
2773 /* Flag this after a successful start. */
2774 session->has_been_started |= 1;
2775 } else {
2776 session->active = 0;
2777 /* Restore initial state on error. */
2778 session->rotated_after_last_stop =
2779 session_rotated_after_last_stop;
2780 session->cleared_after_last_stop =
2781 session_cleared_after_last_stop;
2782 }
2783 end:
2784 return ret;
2785 }
2786
2787 /*
2788 * Command LTTNG_STOP_TRACE processed by the client thread.
2789 */
2790 int cmd_stop_trace(struct ltt_session *session)
2791 {
2792 int ret;
2793 struct ltt_kernel_session *ksession;
2794 struct ltt_ust_session *usess;
2795
2796 assert(session);
2797
2798 DBG("Begin stop session \"%s\" (id %" PRIu64 ")", session->name, session->id);
2799 /* Short cut */
2800 ksession = session->kernel_session;
2801 usess = session->ust_session;
2802
2803 /* Session is not active. Skip everythong and inform the client. */
2804 if (!session->active) {
2805 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2806 goto error;
2807 }
2808
2809 ret = stop_kernel_session(ksession);
2810 if (ret != LTTNG_OK) {
2811 goto error;
2812 }
2813
2814 if (usess && usess->active) {
2815 ret = ust_app_stop_trace_all(usess);
2816 if (ret < 0) {
2817 ret = LTTNG_ERR_UST_STOP_FAIL;
2818 goto error;
2819 }
2820 }
2821
2822 DBG("Completed stop session \"%s\" (id %" PRIu64 ")", session->name,
2823 session->id);
2824 /* Flag inactive after a successful stop. */
2825 session->active = 0;
2826 ret = LTTNG_OK;
2827
2828 error:
2829 return ret;
2830 }
2831
2832 /*
2833 * Set the base_path of the session only if subdir of a control uris is set.
2834 * Return LTTNG_OK on success, otherwise LTTNG_ERR_*.
2835 */
2836 static int set_session_base_path_from_uris(struct ltt_session *session,
2837 size_t nb_uri,
2838 struct lttng_uri *uris)
2839 {
2840 int ret;
2841 size_t i;
2842
2843 for (i = 0; i < nb_uri; i++) {
2844 if (uris[i].stype != LTTNG_STREAM_CONTROL ||
2845 uris[i].subdir[0] == '\0') {
2846 /* Not interested in these URIs */
2847 continue;
2848 }
2849
2850 if (session->base_path != NULL) {
2851 free(session->base_path);
2852 session->base_path = NULL;
2853 }
2854
2855 /* Set session base_path */
2856 session->base_path = strdup(uris[i].subdir);
2857 if (!session->base_path) {
2858 PERROR("Failed to copy base path \"%s\" to session \"%s\"",
2859 uris[i].subdir, session->name);
2860 ret = LTTNG_ERR_NOMEM;
2861 goto error;
2862 }
2863 DBG2("Setting base path \"%s\" for session \"%s\"",
2864 session->base_path, session->name);
2865 }
2866 ret = LTTNG_OK;
2867 error:
2868 return ret;
2869 }
2870
2871 /*
2872 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2873 */
2874 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2875 struct lttng_uri *uris)
2876 {
2877 int ret, i;
2878 struct ltt_kernel_session *ksess = session->kernel_session;
2879 struct ltt_ust_session *usess = session->ust_session;
2880
2881 assert(session);
2882 assert(uris);
2883 assert(nb_uri > 0);
2884
2885 /* Can't set consumer URI if the session is active. */
2886 if (session->active) {
2887 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2888 goto error;
2889 }
2890
2891 /*
2892 * Set the session base path if any. This is done inside
2893 * cmd_set_consumer_uri to preserve backward compatibility of the
2894 * previous session creation api vs the session descriptor api.
2895 */
2896 ret = set_session_base_path_from_uris(session, nb_uri, uris);
2897 if (ret != LTTNG_OK) {
2898 goto error;
2899 }
2900
2901 /* Set the "global" consumer URIs */
2902 for (i = 0; i < nb_uri; i++) {
2903 ret = add_uri_to_consumer(session, session->consumer, &uris[i],
2904 LTTNG_DOMAIN_NONE);
2905 if (ret != LTTNG_OK) {
2906 goto error;
2907 }
2908 }
2909
2910 /* Set UST session URIs */
2911 if (session->ust_session) {
2912 for (i = 0; i < nb_uri; i++) {
2913 ret = add_uri_to_consumer(session,
2914 session->ust_session->consumer,
2915 &uris[i], LTTNG_DOMAIN_UST);
2916 if (ret != LTTNG_OK) {
2917 goto error;
2918 }
2919 }
2920 }
2921
2922 /* Set kernel session URIs */
2923 if (session->kernel_session) {
2924 for (i = 0; i < nb_uri; i++) {
2925 ret = add_uri_to_consumer(session,
2926 session->kernel_session->consumer,
2927 &uris[i], LTTNG_DOMAIN_KERNEL);
2928 if (ret != LTTNG_OK) {
2929 goto error;
2930 }
2931 }
2932 }
2933
2934 /*
2935 * Make sure to set the session in output mode after we set URI since a
2936 * session can be created without URL (thus flagged in no output mode).
2937 */
2938 session->output_traces = 1;
2939 if (ksess) {
2940 ksess->output_traces = 1;
2941 }
2942
2943 if (usess) {
2944 usess->output_traces = 1;
2945 }
2946
2947 /* All good! */
2948 ret = LTTNG_OK;
2949
2950 error:
2951 return ret;
2952 }
2953
2954 static
2955 enum lttng_error_code set_session_output_from_descriptor(
2956 struct ltt_session *session,
2957 const struct lttng_session_descriptor *descriptor)
2958 {
2959 int ret;
2960 enum lttng_error_code ret_code = LTTNG_OK;
2961 enum lttng_session_descriptor_type session_type =
2962 lttng_session_descriptor_get_type(descriptor);
2963 enum lttng_session_descriptor_output_type output_type =
2964 lttng_session_descriptor_get_output_type(descriptor);
2965 struct lttng_uri uris[2] = {};
2966 size_t uri_count = 0;
2967
2968 switch (output_type) {
2969 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NONE:
2970 goto end;
2971 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_LOCAL:
2972 lttng_session_descriptor_get_local_output_uri(descriptor,
2973 &uris[0]);
2974 uri_count = 1;
2975 break;
2976 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NETWORK:
2977 lttng_session_descriptor_get_network_output_uris(descriptor,
2978 &uris[0], &uris[1]);
2979 uri_count = 2;
2980 break;
2981 default:
2982 ret_code = LTTNG_ERR_INVALID;
2983 goto end;
2984 }
2985
2986 switch (session_type) {
2987 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
2988 {
2989 struct snapshot_output *new_output = NULL;
2990
2991 new_output = snapshot_output_alloc();
2992 if (!new_output) {
2993 ret_code = LTTNG_ERR_NOMEM;
2994 goto end;
2995 }
2996
2997 ret = snapshot_output_init_with_uri(session,
2998 DEFAULT_SNAPSHOT_MAX_SIZE,
2999 NULL, uris, uri_count, session->consumer,
3000 new_output, &session->snapshot);
3001 if (ret < 0) {
3002 ret_code = (ret == -ENOMEM) ?
3003 LTTNG_ERR_NOMEM : LTTNG_ERR_INVALID;
3004 snapshot_output_destroy(new_output);
3005 goto end;
3006 }
3007 snapshot_add_output(&session->snapshot, new_output);
3008 break;
3009 }
3010 case LTTNG_SESSION_DESCRIPTOR_TYPE_REGULAR:
3011 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3012 {
3013 ret_code = cmd_set_consumer_uri(session, uri_count, uris);
3014 break;
3015 }
3016 default:
3017 ret_code = LTTNG_ERR_INVALID;
3018 goto end;
3019 }
3020 end:
3021 return ret_code;
3022 }
3023
3024 static
3025 enum lttng_error_code cmd_create_session_from_descriptor(
3026 struct lttng_session_descriptor *descriptor,
3027 const lttng_sock_cred *creds,
3028 const char *home_path)
3029 {
3030 int ret;
3031 enum lttng_error_code ret_code;
3032 const char *session_name;
3033 struct ltt_session *new_session = NULL;
3034 enum lttng_session_descriptor_status descriptor_status;
3035
3036 session_lock_list();
3037 if (home_path) {
3038 if (*home_path != '/') {
3039 ERR("Home path provided by client is not absolute");
3040 ret_code = LTTNG_ERR_INVALID;
3041 goto end;
3042 }
3043 }
3044
3045 descriptor_status = lttng_session_descriptor_get_session_name(
3046 descriptor, &session_name);
3047 switch (descriptor_status) {
3048 case LTTNG_SESSION_DESCRIPTOR_STATUS_OK:
3049 break;
3050 case LTTNG_SESSION_DESCRIPTOR_STATUS_UNSET:
3051 session_name = NULL;
3052 break;
3053 default:
3054 ret_code = LTTNG_ERR_INVALID;
3055 goto end;
3056 }
3057
3058 ret_code = session_create(session_name, creds->uid, creds->gid,
3059 &new_session);
3060 if (ret_code != LTTNG_OK) {
3061 goto end;
3062 }
3063
3064 if (!session_name) {
3065 ret = lttng_session_descriptor_set_session_name(descriptor,
3066 new_session->name);
3067 if (ret) {
3068 ret_code = LTTNG_ERR_SESSION_FAIL;
3069 goto end;
3070 }
3071 }
3072
3073 if (!lttng_session_descriptor_is_output_destination_initialized(
3074 descriptor)) {
3075 /*
3076 * Only include the session's creation time in the output
3077 * destination if the name of the session itself was
3078 * not auto-generated.
3079 */
3080 ret_code = lttng_session_descriptor_set_default_output(
3081 descriptor,
3082 session_name ? &new_session->creation_time : NULL,
3083 home_path);
3084 if (ret_code != LTTNG_OK) {
3085 goto end;
3086 }
3087 } else {
3088 new_session->has_user_specified_directory =
3089 lttng_session_descriptor_has_output_directory(
3090 descriptor);
3091 }
3092
3093 switch (lttng_session_descriptor_get_type(descriptor)) {
3094 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
3095 new_session->snapshot_mode = 1;
3096 break;
3097 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3098 new_session->live_timer =
3099 lttng_session_descriptor_live_get_timer_interval(
3100 descriptor);
3101 break;
3102 default:
3103 break;
3104 }
3105
3106 ret_code = set_session_output_from_descriptor(new_session, descriptor);
3107 if (ret_code != LTTNG_OK) {
3108 goto end;
3109 }
3110 new_session->consumer->enabled = 1;
3111 ret_code = LTTNG_OK;
3112 end:
3113 /* Release reference provided by the session_create function. */
3114 session_put(new_session);
3115 if (ret_code != LTTNG_OK && new_session) {
3116 /* Release the global reference on error. */
3117 session_destroy(new_session);
3118 }
3119 session_unlock_list();
3120 return ret_code;
3121 }
3122
3123 enum lttng_error_code cmd_create_session(struct command_ctx *cmd_ctx, int sock,
3124 struct lttng_session_descriptor **return_descriptor)
3125 {
3126 int ret;
3127 size_t payload_size;
3128 struct lttng_dynamic_buffer payload;
3129 struct lttng_buffer_view home_dir_view;
3130 struct lttng_buffer_view session_descriptor_view;
3131 struct lttng_session_descriptor *session_descriptor = NULL;
3132 enum lttng_error_code ret_code;
3133
3134 lttng_dynamic_buffer_init(&payload);
3135 if (cmd_ctx->lsm->u.create_session.home_dir_size >=
3136 LTTNG_PATH_MAX) {
3137 ret_code = LTTNG_ERR_INVALID;
3138 goto error;
3139 }
3140 if (cmd_ctx->lsm->u.create_session.session_descriptor_size >
3141 LTTNG_SESSION_DESCRIPTOR_MAX_LEN) {
3142 ret_code = LTTNG_ERR_INVALID;
3143 goto error;
3144 }
3145
3146 payload_size = cmd_ctx->lsm->u.create_session.home_dir_size +
3147 cmd_ctx->lsm->u.create_session.session_descriptor_size;
3148 ret = lttng_dynamic_buffer_set_size(&payload, payload_size);
3149 if (ret) {
3150 ret_code = LTTNG_ERR_NOMEM;
3151 goto error;
3152 }
3153
3154 ret = lttcomm_recv_unix_sock(sock, payload.data, payload.size);
3155 if (ret <= 0) {
3156 ERR("Reception of session descriptor failed, aborting.");
3157 ret_code = LTTNG_ERR_SESSION_FAIL;
3158 goto error;
3159 }
3160
3161 home_dir_view = lttng_buffer_view_from_dynamic_buffer(
3162 &payload,
3163 0,
3164 cmd_ctx->lsm->u.create_session.home_dir_size);
3165 session_descriptor_view = lttng_buffer_view_from_dynamic_buffer(
3166 &payload,
3167 cmd_ctx->lsm->u.create_session.home_dir_size,
3168 cmd_ctx->lsm->u.create_session.session_descriptor_size);
3169
3170 ret = lttng_session_descriptor_create_from_buffer(
3171 &session_descriptor_view, &session_descriptor);
3172 if (ret < 0) {
3173 ERR("Failed to create session descriptor from payload of \"create session\" command");
3174 ret_code = LTTNG_ERR_INVALID;
3175 goto error;
3176 }
3177
3178 /*
3179 * Sets the descriptor's auto-generated properties (name, output) if
3180 * needed.
3181 */
3182 ret_code = cmd_create_session_from_descriptor(session_descriptor,
3183 &cmd_ctx->creds,
3184 home_dir_view.size ? home_dir_view.data : NULL);
3185 if (ret_code != LTTNG_OK) {
3186 goto error;
3187 }
3188
3189 ret_code = LTTNG_OK;
3190 *return_descriptor = session_descriptor;
3191 session_descriptor = NULL;
3192 error:
3193 lttng_dynamic_buffer_reset(&payload);
3194 lttng_session_descriptor_destroy(session_descriptor);
3195 return ret_code;
3196 }
3197
3198 static
3199 void cmd_destroy_session_reply(const struct ltt_session *session,
3200 void *_reply_context)
3201 {
3202 int ret;
3203 ssize_t comm_ret;
3204 const struct cmd_destroy_session_reply_context *reply_context =
3205 _reply_context;
3206 struct lttng_dynamic_buffer payload;
3207 struct lttcomm_session_destroy_command_header cmd_header;
3208 struct lttng_trace_archive_location *location = NULL;
3209 struct lttcomm_lttng_msg llm = {
3210 .cmd_type = LTTNG_DESTROY_SESSION,
3211 .ret_code = reply_context->destruction_status,
3212 .pid = UINT32_MAX,
3213 .cmd_header_size =
3214 sizeof(struct lttcomm_session_destroy_command_header),
3215 .data_size = 0,
3216 };
3217 size_t payload_size_before_location;
3218
3219 lttng_dynamic_buffer_init(&payload);
3220
3221 ret = lttng_dynamic_buffer_append(&payload, &llm, sizeof(llm));
3222 if (ret) {
3223 ERR("Failed to append session destruction message");
3224 goto error;
3225 }
3226
3227 cmd_header.rotation_state =
3228 (int32_t) (reply_context->implicit_rotation_on_destroy ?
3229 session->rotation_state :
3230 LTTNG_ROTATION_STATE_NO_ROTATION);
3231 ret = lttng_dynamic_buffer_append(&payload, &cmd_header,
3232 sizeof(cmd_header));
3233 if (ret) {
3234 ERR("Failed to append session destruction command header");
3235 goto error;
3236 }
3237
3238 if (!reply_context->implicit_rotation_on_destroy) {
3239 DBG("No implicit rotation performed during the destruction of session \"%s\", sending reply",
3240 session->name);
3241 goto send_reply;
3242 }
3243 if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED) {
3244 DBG("Rotation state of session \"%s\" is not \"completed\", sending session destruction reply",
3245 session->name);
3246 goto send_reply;
3247 }
3248
3249 location = session_get_trace_archive_location(session);
3250 if (!location) {
3251 ERR("Failed to get the location of the trace archive produced during the destruction of session \"%s\"",
3252 session->name);
3253 goto error;
3254 }
3255
3256 payload_size_before_location = payload.size;
3257 comm_ret = lttng_trace_archive_location_serialize(location,
3258 &payload);
3259 if (comm_ret < 0) {
3260 ERR("Failed to serialize the location of the trace archive produced during the destruction of session \"%s\"",
3261 session->name);
3262 goto error;
3263 }
3264 /* Update the message to indicate the location's length. */
3265 ((struct lttcomm_lttng_msg *) payload.data)->data_size =
3266 payload.size - payload_size_before_location;
3267 send_reply:
3268 comm_ret = lttcomm_send_unix_sock(reply_context->reply_sock_fd,
3269 payload.data, payload.size);
3270 if (comm_ret != (ssize_t) payload.size) {
3271 ERR("Failed to send result of the destruction of session \"%s\" to client",
3272 session->name);
3273 }
3274 error:
3275 ret = close(reply_context->reply_sock_fd);
3276 if (ret) {
3277 PERROR("Failed to close client socket in deferred session destroy reply");
3278 }
3279 lttng_dynamic_buffer_reset(&payload);
3280 free(_reply_context);
3281 }
3282
3283 /*
3284 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3285 *
3286 * Called with session lock held.
3287 */
3288 int cmd_destroy_session(struct ltt_session *session,
3289 struct notification_thread_handle *notification_thread_handle,
3290 int *sock_fd)
3291 {
3292 int ret;
3293 enum lttng_error_code destruction_last_error = LTTNG_OK;
3294 struct cmd_destroy_session_reply_context *reply_context = NULL;
3295
3296 if (sock_fd) {
3297 reply_context = zmalloc(sizeof(*reply_context));
3298 if (!reply_context) {
3299 ret = LTTNG_ERR_NOMEM;
3300 goto end;
3301 }
3302 reply_context->reply_sock_fd = *sock_fd;
3303 }
3304
3305 /* Safety net */
3306 assert(session);
3307
3308 DBG("Begin destroy session %s (id %" PRIu64 ")", session->name,
3309 session->id);
3310 if (session->active) {
3311 DBG("Session \"%s\" is active, attempting to stop it before destroying it",
3312 session->name);
3313 ret = cmd_stop_trace(session);
3314 if (ret != LTTNG_OK && ret != LTTNG_ERR_TRACE_ALREADY_STOPPED) {
3315 /* Carry on with the destruction of the session. */
3316 ERR("Failed to stop session \"%s\" as part of its destruction: %s",
3317 session->name, lttng_strerror(-ret));
3318 destruction_last_error = ret;
3319 }
3320 }
3321
3322 if (session->rotation_schedule_timer_enabled) {
3323 if (timer_session_rotation_schedule_timer_stop(
3324 session)) {
3325 ERR("Failed to stop the \"rotation schedule\" timer of session %s",
3326 session->name);
3327 destruction_last_error = LTTNG_ERR_TIMER_STOP_ERROR;
3328 }
3329 }
3330
3331 if (session->rotate_size) {
3332 unsubscribe_session_consumed_size_rotation(session, notification_thread_handle);
3333 session->rotate_size = 0;
3334 }
3335
3336 if (session->rotated && session->current_trace_chunk && session->output_traces) {
3337 /*
3338 * Perform a last rotation on destruction if rotations have
3339 * occurred during the session's lifetime.
3340 */
3341 ret = cmd_rotate_session(session, NULL, false,
3342 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
3343 if (ret != LTTNG_OK) {
3344 ERR("Failed to perform an implicit rotation as part of the destruction of session \"%s\": %s",
3345 session->name, lttng_strerror(-ret));
3346 destruction_last_error = -ret;
3347 }
3348 if (reply_context) {
3349 reply_context->implicit_rotation_on_destroy = true;
3350 }
3351 } else if (session->has_been_started && session->current_trace_chunk) {
3352 /*
3353 * The user has not triggered a session rotation. However, to
3354 * ensure all data has been consumed, the session is rotated
3355 * to a 'null' trace chunk before it is destroyed.
3356 *
3357 * This is a "quiet" rotation meaning that no notification is
3358 * emitted and no renaming of the current trace chunk takes
3359 * place.
3360 */
3361 ret = cmd_rotate_session(session, NULL, true,
3362 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
3363 if (ret != LTTNG_OK) {
3364 ERR("Failed to perform a quiet rotation as part of the destruction of session \"%s\": %s",
3365 session->name, lttng_strerror(-ret));
3366 destruction_last_error = -ret;
3367 }
3368 }
3369
3370 if (session->shm_path[0]) {
3371 /*
3372 * When a session is created with an explicit shm_path,
3373 * the consumer daemon will create its shared memory files
3374 * at that location and will *not* unlink them. This is normal
3375 * as the intention of that feature is to make it possible
3376 * to retrieve the content of those files should a crash occur.
3377 *
3378 * To ensure the content of those files can be used, the
3379 * sessiond daemon will replicate the content of the metadata
3380 * cache in a metadata file.
3381 *
3382 * On clean-up, it is expected that the consumer daemon will
3383 * unlink the shared memory files and that the session daemon
3384 * will unlink the metadata file. Then, the session's directory
3385 * in the shm path can be removed.
3386 *
3387 * Unfortunately, a flaw in the design of the sessiond's and
3388 * consumerd's tear down of channels makes it impossible to
3389 * determine when the sessiond _and_ the consumerd have both
3390 * destroyed their representation of a channel. For one, the
3391 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3392 * callbacks in both daemons.
3393 *
3394 * However, it is also impossible for the sessiond to know when
3395 * the consumer daemon is done destroying its channel(s) since
3396 * it occurs as a reaction to the closing of the channel's file
3397 * descriptor. There is no resulting communication initiated
3398 * from the consumerd to the sessiond to confirm that the
3399 * operation is completed (and was successful).
3400 *
3401 * Until this is all fixed, the session daemon checks for the
3402 * removal of the session's shm path which makes it possible
3403 * to safely advertise a session as having been destroyed.
3404 *
3405 * Prior to this fix, it was not possible to reliably save
3406 * a session making use of the --shm-path option, destroy it,
3407 * and load it again. This is because the creation of the
3408 * session would fail upon seeing the session's shm path
3409 * already in existence.
3410 *
3411 * Note that none of the error paths in the check for the
3412 * directory's existence return an error. This is normal
3413 * as there isn't much that can be done. The session will
3414 * be destroyed properly, except that we can't offer the
3415 * guarantee that the same session can be re-created.
3416 */
3417 current_completion_handler = &destroy_completion_handler.handler;
3418 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3419 session->shm_path,
3420 sizeof(destroy_completion_handler.shm_path));
3421 assert(!ret);
3422 }
3423
3424 /*
3425 * The session is destroyed. However, note that the command context
3426 * still holds a reference to the session, thus delaying its destruction
3427 * _at least_ up to the point when that reference is released.
3428 */
3429 session_destroy(session);
3430 if (reply_context) {
3431 reply_context->destruction_status = destruction_last_error;
3432 ret = session_add_destroy_notifier(session,
3433 cmd_destroy_session_reply,
3434 (void *) reply_context);
3435 if (ret) {
3436 ret = LTTNG_ERR_FATAL;
3437 goto end;
3438 } else {
3439 *sock_fd = -1;
3440 }
3441 }
3442 ret = LTTNG_OK;
3443 end:
3444 return ret;
3445 }
3446
3447 /*
3448 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3449 */
3450 int cmd_register_consumer(struct ltt_session *session,
3451 enum lttng_domain_type domain, const char *sock_path,
3452 struct consumer_data *cdata)
3453 {
3454 int ret, sock;
3455 struct consumer_socket *socket = NULL;
3456
3457 assert(session);
3458 assert(cdata);
3459 assert(sock_path);
3460
3461 switch (domain) {
3462 case LTTNG_DOMAIN_KERNEL:
3463 {
3464 struct ltt_kernel_session *ksess = session->kernel_session;
3465
3466 assert(ksess);
3467
3468 /* Can't register a consumer if there is already one */
3469 if (ksess->consumer_fds_sent != 0) {
3470 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3471 goto error;
3472 }
3473
3474 sock = lttcomm_connect_unix_sock(sock_path);
3475 if (sock < 0) {
3476 ret = LTTNG_ERR_CONNECT_FAIL;
3477 goto error;
3478 }
3479 cdata->cmd_sock = sock;
3480
3481 socket = consumer_allocate_socket(&cdata->cmd_sock);
3482 if (socket == NULL) {
3483 ret = close(sock);
3484 if (ret < 0) {
3485 PERROR("close register consumer");
3486 }
3487 cdata->cmd_sock = -1;
3488 ret = LTTNG_ERR_FATAL;
3489 goto error;
3490 }
3491
3492 socket->lock = zmalloc(sizeof(pthread_mutex_t));
3493 if (socket->lock == NULL) {
3494 PERROR("zmalloc pthread mutex");
3495 ret = LTTNG_ERR_FATAL;
3496 goto error;
3497 }
3498 pthread_mutex_init(socket->lock, NULL);
3499 socket->registered = 1;
3500
3501 rcu_read_lock();
3502 consumer_add_socket(socket, ksess->consumer);
3503 rcu_read_unlock();
3504
3505 pthread_mutex_lock(&cdata->pid_mutex);
3506 cdata->pid = -1;
3507 pthread_mutex_unlock(&cdata->pid_mutex);
3508
3509 break;
3510 }
3511 default:
3512 /* TODO: Userspace tracing */
3513 ret = LTTNG_ERR_UND;
3514 goto error;
3515 }
3516
3517 return LTTNG_OK;
3518
3519 error:
3520 if (socket) {
3521 consumer_destroy_socket(socket);
3522 }
3523 return ret;
3524 }
3525
3526 /*
3527 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3528 */
3529 ssize_t cmd_list_domains(struct ltt_session *session,
3530 struct lttng_domain **domains)
3531 {
3532 int ret, index = 0;
3533 ssize_t nb_dom = 0;
3534 struct agent *agt;
3535 struct lttng_ht_iter iter;
3536
3537 if (session->kernel_session != NULL) {
3538 DBG3("Listing domains found kernel domain");
3539 nb_dom++;
3540 }
3541
3542 if (session->ust_session != NULL) {
3543 DBG3("Listing domains found UST global domain");
3544 nb_dom++;
3545
3546 rcu_read_lock();
3547 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3548 agt, node.node) {
3549 if (agt->being_used) {
3550 nb_dom++;
3551 }
3552 }
3553 rcu_read_unlock();
3554 }
3555
3556 if (!nb_dom) {
3557 goto end;
3558 }
3559
3560 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3561 if (*domains == NULL) {
3562 ret = LTTNG_ERR_FATAL;
3563 goto error;
3564 }
3565
3566 if (session->kernel_session != NULL) {
3567 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3568
3569 /* Kernel session buffer type is always GLOBAL */
3570 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3571
3572 index++;
3573 }
3574
3575 if (session->ust_session != NULL) {
3576 (*domains)[index].type = LTTNG_DOMAIN_UST;
3577 (*domains)[index].buf_type = session->ust_session->buffer_type;
3578 index++;
3579
3580 rcu_read_lock();
3581 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3582 agt, node.node) {
3583 if (agt->being_used) {
3584 (*domains)[index].type = agt->domain;
3585 (*domains)[index].buf_type = session->ust_session->buffer_type;
3586 index++;
3587 }
3588 }
3589 rcu_read_unlock();
3590 }
3591 end:
3592 return nb_dom;
3593
3594 error:
3595 /* Return negative value to differentiate return code */
3596 return -ret;
3597 }
3598
3599
3600 /*
3601 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3602 */
3603 ssize_t cmd_list_channels(enum lttng_domain_type domain,
3604 struct ltt_session *session, struct lttng_channel **channels)
3605 {
3606 ssize_t nb_chan = 0, payload_size = 0, ret;
3607
3608 switch (domain) {
3609 case LTTNG_DOMAIN_KERNEL:
3610 if (session->kernel_session != NULL) {
3611 nb_chan = session->kernel_session->channel_count;
3612 }
3613 DBG3("Number of kernel channels %zd", nb_chan);
3614 if (nb_chan <= 0) {
3615 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
3616 goto end;
3617 }
3618 break;
3619 case LTTNG_DOMAIN_UST:
3620 if (session->ust_session != NULL) {
3621 rcu_read_lock();
3622 nb_chan = lttng_ht_get_count(
3623 session->ust_session->domain_global.channels);
3624 rcu_read_unlock();
3625 }
3626 DBG3("Number of UST global channels %zd", nb_chan);
3627 if (nb_chan < 0) {
3628 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
3629 goto end;
3630 }
3631 break;
3632 default:
3633 ret = -LTTNG_ERR_UND;
3634 goto end;
3635 }
3636
3637 if (nb_chan > 0) {
3638 const size_t channel_size = sizeof(struct lttng_channel) +
3639 sizeof(struct lttng_channel_extended);
3640 struct lttng_channel_extended *channel_exts;
3641
3642 payload_size = nb_chan * channel_size;
3643 *channels = zmalloc(payload_size);
3644 if (*channels == NULL) {
3645 ret = -LTTNG_ERR_FATAL;
3646 goto end;
3647 }
3648
3649 channel_exts = ((void *) *channels) +
3650 (nb_chan * sizeof(struct lttng_channel));
3651 ret = list_lttng_channels(domain, session, *channels, channel_exts);
3652 if (ret != LTTNG_OK) {
3653 free(*channels);
3654 *channels = NULL;
3655 goto end;
3656 }
3657 } else {
3658 *channels = NULL;
3659 }
3660
3661 ret = payload_size;
3662 end:
3663 return ret;
3664 }
3665
3666 /*
3667 * Command LTTNG_LIST_EVENTS processed by the client thread.
3668 */
3669 ssize_t cmd_list_events(enum lttng_domain_type domain,
3670 struct ltt_session *session, char *channel_name,
3671 struct lttng_event **events, size_t *total_size)
3672 {
3673 int ret = 0;
3674 ssize_t nb_event = 0;
3675
3676 switch (domain) {
3677 case LTTNG_DOMAIN_KERNEL:
3678 if (session->kernel_session != NULL) {
3679 nb_event = list_lttng_kernel_events(channel_name,
3680 session->kernel_session, events,
3681 total_size);
3682 }
3683 break;
3684 case LTTNG_DOMAIN_UST:
3685 {
3686 if (session->ust_session != NULL) {
3687 nb_event = list_lttng_ust_global_events(channel_name,
3688 &session->ust_session->domain_global, events,
3689 total_size);
3690 }
3691 break;
3692 }
3693 case LTTNG_DOMAIN_LOG4J:
3694 case LTTNG_DOMAIN_JUL:
3695 case LTTNG_DOMAIN_PYTHON:
3696 if (session->ust_session) {
3697 struct lttng_ht_iter iter;
3698 struct agent *agt;
3699
3700 rcu_read_lock();
3701 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3702 &iter.iter, agt, node.node) {
3703 if (agt->domain == domain) {
3704 nb_event = list_lttng_agent_events(
3705 agt, events,
3706 total_size);
3707 break;
3708 }
3709 }
3710 rcu_read_unlock();
3711 }
3712 break;
3713 default:
3714 ret = LTTNG_ERR_UND;
3715 goto error;
3716 }
3717
3718 return nb_event;
3719
3720 error:
3721 /* Return negative value to differentiate return code */
3722 return -ret;
3723 }
3724
3725 /*
3726 * Using the session list, filled a lttng_session array to send back to the
3727 * client for session listing.
3728 *
3729 * The session list lock MUST be acquired before calling this function. Use
3730 * session_lock_list() and session_unlock_list().
3731 */
3732 void cmd_list_lttng_sessions(struct lttng_session *sessions,
3733 size_t session_count, uid_t uid, gid_t gid)
3734 {
3735 int ret;
3736 unsigned int i = 0;
3737 struct ltt_session *session;
3738 struct ltt_session_list *list = session_get_list();
3739 struct lttng_session_extended *extended =
3740 (typeof(extended)) (&sessions[session_count]);
3741
3742 DBG("Getting all available session for UID %d GID %d",
3743 uid, gid);
3744 /*
3745 * Iterate over session list and append data after the control struct in
3746 * the buffer.
3747 */
3748 cds_list_for_each_entry(session, &list->head, list) {
3749 if (!session_get(session)) {
3750 continue;
3751 }
3752 /*
3753 * Only list the sessions the user can control.
3754 */
3755 if (!session_access_ok(session, uid, gid) ||
3756 session->destroyed) {
3757 session_put(session);
3758 continue;
3759 }
3760
3761 struct ltt_kernel_session *ksess = session->kernel_session;
3762 struct ltt_ust_session *usess = session->ust_session;
3763
3764 if (session->consumer->type == CONSUMER_DST_NET ||
3765 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3766 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3767 ret = build_network_session_path(sessions[i].path,
3768 sizeof(sessions[i].path), session);
3769 } else {
3770 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3771 session->consumer->dst.session_root_path);
3772 }
3773 if (ret < 0) {
3774 PERROR("snprintf session path");
3775 session_put(session);
3776 continue;
3777 }
3778
3779 strncpy(sessions[i].name, session->name, NAME_MAX);
3780 sessions[i].name[NAME_MAX - 1] = '\0';
3781 sessions[i].enabled = session->active;
3782 sessions[i].snapshot_mode = session->snapshot_mode;
3783 sessions[i].live_timer_interval = session->live_timer;
3784 extended[i].creation_time.value = (uint64_t) session->creation_time;
3785 extended[i].creation_time.is_set = 1;
3786 i++;
3787 session_put(session);
3788 }
3789 }
3790
3791 /*
3792 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3793 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3794 */
3795 int cmd_data_pending(struct ltt_session *session)
3796 {
3797 int ret;
3798 struct ltt_kernel_session *ksess = session->kernel_session;
3799 struct ltt_ust_session *usess = session->ust_session;
3800
3801 assert(session);
3802
3803 DBG("Data pending for session %s", session->name);
3804
3805 /* Session MUST be stopped to ask for data availability. */
3806 if (session->active) {
3807 ret = LTTNG_ERR_SESSION_STARTED;
3808 goto error;
3809 } else {
3810 /*
3811 * If stopped, just make sure we've started before else the above call
3812 * will always send that there is data pending.
3813 *
3814 * The consumer assumes that when the data pending command is received,
3815 * the trace has been started before or else no output data is written
3816 * by the streams which is a condition for data pending. So, this is
3817 * *VERY* important that we don't ask the consumer before a start
3818 * trace.
3819 */
3820 if (!session->has_been_started) {
3821 ret = 0;
3822 goto error;
3823 }
3824 }
3825
3826 /* A rotation is still pending, we have to wait. */
3827 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
3828 DBG("Rotate still pending for session %s", session->name);
3829 ret = 1;
3830 goto error;
3831 }
3832
3833 if (ksess && ksess->consumer) {
3834 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3835 if (ret == 1) {
3836 /* Data is still being extracted for the kernel. */
3837 goto error;
3838 }
3839 }
3840
3841 if (usess && usess->consumer) {
3842 ret = consumer_is_data_pending(usess->id, usess->consumer);
3843 if (ret == 1) {
3844 /* Data is still being extracted for the kernel. */
3845 goto error;
3846 }
3847 }
3848
3849 /* Data is ready to be read by a viewer */
3850 ret = 0;
3851
3852 error:
3853 return ret;
3854 }
3855
3856 /*
3857 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3858 *
3859 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3860 */
3861 int cmd_snapshot_add_output(struct ltt_session *session,
3862 const struct lttng_snapshot_output *output, uint32_t *id)
3863 {
3864 int ret;
3865 struct snapshot_output *new_output;
3866
3867 assert(session);
3868 assert(output);
3869
3870 DBG("Cmd snapshot add output for session %s", session->name);
3871
3872 /*
3873 * Can't create an output if the session is not set in no-output mode.
3874 */
3875 if (session->output_traces) {
3876 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3877 goto error;
3878 }
3879
3880 if (session->has_non_mmap_channel) {
3881 ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
3882 goto error;
3883 }
3884
3885 /* Only one output is allowed until we have the "tee" feature. */
3886 if (session->snapshot.nb_output == 1) {
3887 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3888 goto error;
3889 }
3890
3891 new_output = snapshot_output_alloc();
3892 if (!new_output) {
3893 ret = LTTNG_ERR_NOMEM;
3894 goto error;
3895 }
3896
3897 ret = snapshot_output_init(session, output->max_size, output->name,
3898 output->ctrl_url, output->data_url, session->consumer, new_output,
3899 &session->snapshot);
3900 if (ret < 0) {
3901 if (ret == -ENOMEM) {
3902 ret = LTTNG_ERR_NOMEM;
3903 } else {
3904 ret = LTTNG_ERR_INVALID;
3905 }
3906 goto free_error;
3907 }
3908
3909 rcu_read_lock();
3910 snapshot_add_output(&session->snapshot, new_output);
3911 if (id) {
3912 *id = new_output->id;
3913 }
3914 rcu_read_unlock();
3915
3916 return LTTNG_OK;
3917
3918 free_error:
3919 snapshot_output_destroy(new_output);
3920 error:
3921 return ret;
3922 }
3923
3924 /*
3925 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3926 *
3927 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3928 */
3929 int cmd_snapshot_del_output(struct ltt_session *session,
3930 const struct lttng_snapshot_output *output)
3931 {
3932 int ret;
3933 struct snapshot_output *sout = NULL;
3934
3935 assert(session);
3936 assert(output);
3937
3938 rcu_read_lock();
3939
3940 /*
3941 * Permission denied to create an output if the session is not
3942 * set in no output mode.
3943 */
3944 if (session->output_traces) {
3945 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3946 goto error;
3947 }
3948
3949 if (output->id) {
3950 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
3951 session->name);
3952 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
3953 } else if (*output->name != '\0') {
3954 DBG("Cmd snapshot del output name %s for session %s", output->name,
3955 session->name);
3956 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
3957 }
3958 if (!sout) {
3959 ret = LTTNG_ERR_INVALID;
3960 goto error;
3961 }
3962
3963 snapshot_delete_output(&session->snapshot, sout);
3964 snapshot_output_destroy(sout);
3965 ret = LTTNG_OK;
3966
3967 error:
3968 rcu_read_unlock();
3969 return ret;
3970 }
3971
3972 /*
3973 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
3974 *
3975 * If no output is available, outputs is untouched and 0 is returned.
3976 *
3977 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
3978 */
3979 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
3980 struct lttng_snapshot_output **outputs)
3981 {
3982 int ret, idx = 0;
3983 struct lttng_snapshot_output *list = NULL;
3984 struct lttng_ht_iter iter;
3985 struct snapshot_output *output;
3986
3987 assert(session);
3988 assert(outputs);
3989
3990 DBG("Cmd snapshot list outputs for session %s", session->name);
3991
3992 /*
3993 * Permission denied to create an output if the session is not
3994 * set in no output mode.
3995 */
3996 if (session->output_traces) {
3997 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3998 goto end;
3999 }
4000
4001 if (session->snapshot.nb_output == 0) {
4002 ret = 0;
4003 goto end;
4004 }
4005
4006 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
4007 if (!list) {
4008 ret = -LTTNG_ERR_NOMEM;
4009 goto end;
4010 }
4011
4012 /* Copy list from session to the new list object. */
4013 rcu_read_lock();
4014 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
4015 output, node.node) {
4016 assert(output->consumer);
4017 list[idx].id = output->id;
4018 list[idx].max_size = output->max_size;
4019 if (lttng_strncpy(list[idx].name, output->name,
4020 sizeof(list[idx].name))) {
4021 ret = -LTTNG_ERR_INVALID;
4022 goto error;
4023 }
4024 if (output->consumer->type == CONSUMER_DST_LOCAL) {
4025 if (lttng_strncpy(list[idx].ctrl_url,
4026 output->consumer->dst.session_root_path,
4027 sizeof(list[idx].ctrl_url))) {
4028 ret = -LTTNG_ERR_INVALID;
4029 goto error;
4030 }
4031 } else {
4032 /* Control URI. */
4033 ret = uri_to_str_url(&output->consumer->dst.net.control,
4034 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
4035 if (ret < 0) {
4036 ret = -LTTNG_ERR_NOMEM;
4037 goto error;
4038 }
4039
4040 /* Data URI. */
4041 ret = uri_to_str_url(&output->consumer->dst.net.data,
4042 list[idx].data_url, sizeof(list[idx].data_url));
4043 if (ret < 0) {
4044 ret = -LTTNG_ERR_NOMEM;
4045 goto error;
4046 }
4047 }
4048 idx++;
4049 }
4050
4051 *outputs = list;
4052 list = NULL;
4053 ret = session->snapshot.nb_output;
4054 error:
4055 rcu_read_unlock();
4056 free(list);
4057 end:
4058 return ret;
4059 }
4060
4061 /*
4062 * Check if we can regenerate the metadata for this session.
4063 * Only kernel, UST per-uid and non-live sessions are supported.
4064 *
4065 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
4066 */
4067 static
4068 int check_regenerate_metadata_support(struct ltt_session *session)
4069 {
4070 int ret;
4071
4072 assert(session);
4073
4074 if (session->live_timer != 0) {
4075 ret = LTTNG_ERR_LIVE_SESSION;
4076 goto end;
4077 }
4078 if (!session->active) {
4079 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4080 goto end;
4081 }
4082 if (session->ust_session) {
4083 switch (session->ust_session->buffer_type) {
4084 case LTTNG_BUFFER_PER_UID:
4085 break;
4086 case LTTNG_BUFFER_PER_PID:
4087 ret = LTTNG_ERR_PER_PID_SESSION;
4088 goto end;
4089 default:
4090 assert(0);
4091 ret = LTTNG_ERR_UNK;
4092 goto end;
4093 }
4094 }
4095 if (session->consumer->type == CONSUMER_DST_NET &&
4096 session->consumer->relay_minor_version < 8) {
4097 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
4098 goto end;
4099 }
4100 ret = 0;
4101
4102 end:
4103 return ret;
4104 }
4105
4106 static
4107 int clear_metadata_file(int fd)
4108 {
4109 int ret;
4110 off_t lseek_ret;
4111
4112 lseek_ret = lseek(fd, 0, SEEK_SET);
4113 if (lseek_ret < 0) {
4114 PERROR("lseek");
4115 ret = -1;
4116 goto end;
4117 }
4118
4119 ret = ftruncate(fd, 0);
4120 if (ret < 0) {
4121 PERROR("ftruncate");
4122 goto end;
4123 }
4124
4125 end:
4126 return ret;
4127 }
4128
4129 static
4130 int ust_regenerate_metadata(struct ltt_ust_session *usess)
4131 {
4132 int ret = 0;
4133 struct buffer_reg_uid *uid_reg = NULL;
4134 struct buffer_reg_session *session_reg = NULL;
4135
4136 rcu_read_lock();
4137 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
4138 struct ust_registry_session *registry;
4139 struct ust_registry_channel *chan;
4140 struct lttng_ht_iter iter_chan;
4141
4142 session_reg = uid_reg->registry;
4143 registry = session_reg->reg.ust;
4144
4145 pthread_mutex_lock(&registry->lock);
4146 registry->metadata_len_sent = 0;
4147 memset(registry->metadata, 0, registry->metadata_alloc_len);
4148 registry->metadata_len = 0;
4149 registry->metadata_version++;
4150 if (registry->metadata_fd > 0) {
4151 /* Clear the metadata file's content. */
4152 ret = clear_metadata_file(registry->metadata_fd);
4153 if (ret) {
4154 pthread_mutex_unlock(&registry->lock);
4155 goto end;
4156 }
4157 }
4158
4159 ret = ust_metadata_session_statedump(registry, NULL,
4160 registry->major, registry->minor);
4161 if (ret) {
4162 pthread_mutex_unlock(&registry->lock);
4163 ERR("Failed to generate session metadata (err = %d)",
4164 ret);
4165 goto end;
4166 }
4167 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
4168 chan, node.node) {
4169 struct ust_registry_event *event;
4170 struct lttng_ht_iter iter_event;
4171
4172 ret = ust_metadata_channel_statedump(registry, chan);
4173 if (ret) {
4174 pthread_mutex_unlock(&registry->lock);
4175 ERR("Failed to generate channel metadata "
4176 "(err = %d)", ret);
4177 goto end;
4178 }
4179 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
4180 event, node.node) {
4181 ret = ust_metadata_event_statedump(registry,
4182 chan, event);
4183 if (ret) {
4184 pthread_mutex_unlock(&registry->lock);
4185 ERR("Failed to generate event metadata "
4186 "(err = %d)", ret);
4187 goto end;
4188 }
4189 }
4190 }
4191 pthread_mutex_unlock(&registry->lock);
4192 }
4193
4194 end:
4195 rcu_read_unlock();
4196 return ret;
4197 }
4198
4199 /*
4200 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
4201 *
4202 * Ask the consumer to truncate the existing metadata file(s) and
4203 * then regenerate the metadata. Live and per-pid sessions are not
4204 * supported and return an error.
4205 *
4206 * Return 0 on success or else a LTTNG_ERR code.
4207 */
4208 int cmd_regenerate_metadata(struct ltt_session *session)
4209 {
4210 int ret;
4211
4212 assert(session);
4213
4214 ret = check_regenerate_metadata_support(session);
4215 if (ret) {
4216 goto end;
4217 }
4218
4219 if (session->kernel_session) {
4220 ret = kernctl_session_regenerate_metadata(
4221 session->kernel_session->fd);
4222 if (ret < 0) {
4223 ERR("Failed to regenerate the kernel metadata");
4224 goto end;
4225 }
4226 }
4227
4228 if (session->ust_session) {
4229 ret = ust_regenerate_metadata(session->ust_session);
4230 if (ret < 0) {
4231 ERR("Failed to regenerate the UST metadata");
4232 goto end;
4233 }
4234 }
4235 DBG("Cmd metadata regenerate for session %s", session->name);
4236 ret = LTTNG_OK;
4237
4238 end:
4239 return ret;
4240 }
4241
4242 /*
4243 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
4244 *
4245 * Ask the tracer to regenerate a new statedump.
4246 *
4247 * Return 0 on success or else a LTTNG_ERR code.
4248 */
4249 int cmd_regenerate_statedump(struct ltt_session *session)
4250 {
4251 int ret;
4252
4253 assert(session);
4254
4255 if (!session->active) {
4256 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4257 goto end;
4258 }
4259
4260 if (session->kernel_session) {
4261 ret = kernctl_session_regenerate_statedump(
4262 session->kernel_session->fd);
4263 /*
4264 * Currently, the statedump in kernel can only fail if out
4265 * of memory.
4266 */
4267 if (ret < 0) {
4268 if (ret == -ENOMEM) {
4269 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
4270 } else {
4271 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4272 }
4273 ERR("Failed to regenerate the kernel statedump");
4274 goto end;
4275 }
4276 }
4277
4278 if (session->ust_session) {
4279 ret = ust_app_regenerate_statedump_all(session->ust_session);
4280 /*
4281 * Currently, the statedump in UST always returns 0.
4282 */
4283 if (ret < 0) {
4284 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4285 ERR("Failed to regenerate the UST statedump");
4286 goto end;
4287 }
4288 }
4289 DBG("Cmd regenerate statedump for session %s", session->name);
4290 ret = LTTNG_OK;
4291
4292 end:
4293 return ret;
4294 }
4295
4296 int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
4297 struct notification_thread_handle *notification_thread)
4298 {
4299 int ret;
4300 size_t trigger_len;
4301 ssize_t sock_recv_len;
4302 struct lttng_trigger *trigger = NULL;
4303 struct lttng_buffer_view view;
4304 struct lttng_dynamic_buffer trigger_buffer;
4305
4306 lttng_dynamic_buffer_init(&trigger_buffer);
4307 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4308 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4309 if (ret) {
4310 ret = LTTNG_ERR_NOMEM;
4311 goto end;
4312 }
4313
4314 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4315 trigger_len);
4316 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4317 ERR("Failed to receive \"register trigger\" command payload");
4318 /* TODO: should this be a new error enum ? */
4319 ret = LTTNG_ERR_INVALID_TRIGGER;
4320 goto end;
4321 }
4322
4323 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4324 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4325 trigger_len) {
4326 ERR("Invalid trigger payload received in \"register trigger\" command");
4327 ret = LTTNG_ERR_INVALID_TRIGGER;
4328 goto end;
4329 }
4330
4331 ret = notification_thread_command_register_trigger(notification_thread,
4332 trigger);
4333 /* Ownership of trigger was transferred. */
4334 trigger = NULL;
4335 end:
4336 lttng_trigger_destroy(trigger);
4337 lttng_dynamic_buffer_reset(&trigger_buffer);
4338 return ret;
4339 }
4340
4341 int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
4342 struct notification_thread_handle *notification_thread)
4343 {
4344 int ret;
4345 size_t trigger_len;
4346 ssize_t sock_recv_len;
4347 struct lttng_trigger *trigger = NULL;
4348 struct lttng_buffer_view view;
4349 struct lttng_dynamic_buffer trigger_buffer;
4350
4351 lttng_dynamic_buffer_init(&trigger_buffer);
4352 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4353 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4354 if (ret) {
4355 ret = LTTNG_ERR_NOMEM;
4356 goto end;
4357 }
4358
4359 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4360 trigger_len);
4361 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4362 ERR("Failed to receive \"unregister trigger\" command payload");
4363 /* TODO: should this be a new error enum ? */
4364 ret = LTTNG_ERR_INVALID_TRIGGER;
4365 goto end;
4366 }
4367
4368 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4369 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4370 trigger_len) {
4371 ERR("Invalid trigger payload received in \"unregister trigger\" command");
4372 ret = LTTNG_ERR_INVALID_TRIGGER;
4373 goto end;
4374 }
4375
4376 ret = notification_thread_command_unregister_trigger(notification_thread,
4377 trigger);
4378 end:
4379 lttng_trigger_destroy(trigger);
4380 lttng_dynamic_buffer_reset(&trigger_buffer);
4381 return ret;
4382 }
4383
4384 /*
4385 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4386 * snapshot output is *not* set with a remote destination.
4387 *
4388 * Return LTTNG_OK on success or a LTTNG_ERR code.
4389 */
4390 static enum lttng_error_code set_relayd_for_snapshot(
4391 struct consumer_output *output,
4392 const struct ltt_session *session)
4393 {
4394 enum lttng_error_code status = LTTNG_OK;
4395 struct lttng_ht_iter iter;
4396 struct consumer_socket *socket;
4397 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
4398 const char *base_path;
4399
4400 assert(output);
4401 assert(session);
4402
4403 DBG2("Set relayd object from snapshot output");
4404
4405 if (session->current_trace_chunk) {
4406 enum lttng_trace_chunk_status chunk_status =
4407 lttng_trace_chunk_get_id(
4408 session->current_trace_chunk,
4409 &current_chunk_id.value);
4410
4411 if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK) {
4412 current_chunk_id.is_set = true;
4413 } else {
4414 ERR("Failed to get current trace chunk id");
4415 status = LTTNG_ERR_UNK;
4416 goto error;
4417 }
4418 }
4419
4420 /* Ignore if snapshot consumer output is not network. */
4421 if (output->type != CONSUMER_DST_NET) {
4422 goto error;
4423 }
4424
4425 /*
4426 * The snapshot record URI base path overrides the session
4427 * base path.
4428 */
4429 if (output->dst.net.control.subdir[0] != '\0') {
4430 base_path = output->dst.net.control.subdir;
4431 } else {
4432 base_path = session->base_path;
4433 }
4434
4435 /*
4436 * For each consumer socket, create and send the relayd object of the
4437 * snapshot output.
4438 */
4439 rcu_read_lock();
4440 cds_lfht_for_each_entry(output->socks->ht, &iter.iter,
4441 socket, node.node) {
4442 pthread_mutex_lock(socket->lock);
4443 status = send_consumer_relayd_sockets(0, session->id,
4444 output, socket,
4445 session->name, session->hostname,
4446 base_path,
4447 session->live_timer,
4448 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
4449 session->creation_time,
4450 session->name_contains_creation_time);
4451 pthread_mutex_unlock(socket->lock);
4452 if (status != LTTNG_OK) {
4453 rcu_read_unlock();
4454 goto error;
4455 }
4456 }
4457 rcu_read_unlock();
4458
4459 error:
4460 return status;
4461 }
4462
4463 /*
4464 * Record a kernel snapshot.
4465 *
4466 * Return LTTNG_OK on success or a LTTNG_ERR code.
4467 */
4468 static enum lttng_error_code record_kernel_snapshot(
4469 struct ltt_kernel_session *ksess,
4470 const struct consumer_output *output,
4471 const struct ltt_session *session,
4472 int wait, uint64_t nb_packets_per_stream)
4473 {
4474 enum lttng_error_code status;
4475
4476 assert(ksess);
4477 assert(output);
4478 assert(session);
4479
4480 status = kernel_snapshot_record(
4481 ksess, output, wait, nb_packets_per_stream);
4482 return status;
4483 }
4484
4485 /*
4486 * Record a UST snapshot.
4487 *
4488 * Returns LTTNG_OK on success or a LTTNG_ERR error code.
4489 */
4490 static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
4491 const struct consumer_output *output,
4492 const struct ltt_session *session,
4493 int wait, uint64_t nb_packets_per_stream)
4494 {
4495 enum lttng_error_code status;
4496
4497 assert(usess);
4498 assert(output);
4499 assert(session);
4500
4501 status = ust_app_snapshot_record(
4502 usess, output, wait, nb_packets_per_stream);
4503 return status;
4504 }
4505
4506 static
4507 uint64_t get_session_size_one_more_packet_per_stream(
4508 const struct ltt_session *session, uint64_t cur_nr_packets)
4509 {
4510 uint64_t tot_size = 0;
4511
4512 if (session->kernel_session) {
4513 struct ltt_kernel_channel *chan;
4514 const struct ltt_kernel_session *ksess =
4515 session->kernel_session;
4516
4517 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
4518 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
4519 /*
4520 * Don't take channel into account if we
4521 * already grab all its packets.
4522 */
4523 continue;
4524 }
4525 tot_size += chan->channel->attr.subbuf_size
4526 * chan->stream_count;
4527 }
4528 }
4529
4530 if (session->ust_session) {
4531 const struct ltt_ust_session *usess = session->ust_session;
4532
4533 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
4534 cur_nr_packets);
4535 }
4536
4537 return tot_size;
4538 }
4539
4540 /*
4541 * Calculate the number of packets we can grab from each stream that
4542 * fits within the overall snapshot max size.
4543 *
4544 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
4545 * the number of packets per stream.
4546 *
4547 * TODO: this approach is not perfect: we consider the worse case
4548 * (packet filling the sub-buffers) as an upper bound, but we could do
4549 * better if we do this calculation while we actually grab the packet
4550 * content: we would know how much padding we don't actually store into
4551 * the file.
4552 *
4553 * This algorithm is currently bounded by the number of packets per
4554 * stream.
4555 *
4556 * Since we call this algorithm before actually grabbing the data, it's
4557 * an approximation: for instance, applications could appear/disappear
4558 * in between this call and actually grabbing data.
4559 */
4560 static
4561 int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
4562 uint64_t max_size)
4563 {
4564 int64_t size_left;
4565 uint64_t cur_nb_packets = 0;
4566
4567 if (!max_size) {
4568 return 0; /* Infinite */
4569 }
4570
4571 size_left = max_size;
4572 for (;;) {
4573 uint64_t one_more_packet_tot_size;
4574
4575 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(
4576 session, cur_nb_packets);
4577 if (!one_more_packet_tot_size) {
4578 /* We are already grabbing all packets. */
4579 break;
4580 }
4581 size_left -= one_more_packet_tot_size;
4582 if (size_left < 0) {
4583 break;
4584 }
4585 cur_nb_packets++;
4586 }
4587 if (!cur_nb_packets) {
4588 /* Not enough room to grab one packet of each stream, error. */
4589 return -1;
4590 }
4591 return cur_nb_packets;
4592 }
4593
4594 static
4595 enum lttng_error_code snapshot_record(struct ltt_session *session,
4596 const struct snapshot_output *snapshot_output, int wait)
4597 {
4598 int64_t nb_packets_per_stream;
4599 char snapshot_chunk_name[LTTNG_NAME_MAX];
4600 int ret;
4601 enum lttng_error_code ret_code = LTTNG_OK;
4602 struct lttng_trace_chunk *snapshot_trace_chunk;
4603 struct consumer_output *original_ust_consumer_output = NULL;
4604 struct consumer_output *original_kernel_consumer_output = NULL;
4605 struct consumer_output *snapshot_ust_consumer_output = NULL;
4606 struct consumer_output *snapshot_kernel_consumer_output = NULL;
4607
4608 ret = snprintf(snapshot_chunk_name, sizeof(snapshot_chunk_name),
4609 "%s-%s-%" PRIu64,
4610 snapshot_output->name,
4611 snapshot_output->datetime,
4612 snapshot_output->nb_snapshot);
4613 if (ret < 0 || ret >= sizeof(snapshot_chunk_name)) {
4614 ERR("Failed to format snapshot name");
4615 ret_code = LTTNG_ERR_INVALID;
4616 goto error;
4617 }
4618 DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
4619 snapshot_output->name, session->name,
4620 snapshot_chunk_name);
4621 if (!session->kernel_session && !session->ust_session) {
4622 ERR("Failed to record snapshot as no channels exist");
4623 ret_code = LTTNG_ERR_NO_CHANNEL;
4624 goto error;
4625 }
4626
4627 if (session->kernel_session) {
4628 original_kernel_consumer_output =
4629 session->kernel_session->consumer;
4630 snapshot_kernel_consumer_output =
4631 consumer_copy_output(snapshot_output->consumer);
4632 strcpy(snapshot_kernel_consumer_output->chunk_path,
4633 snapshot_chunk_name);
4634 ret = consumer_copy_sockets(snapshot_kernel_consumer_output,
4635 original_kernel_consumer_output);
4636 if (ret < 0) {
4637 ERR("Failed to copy consumer sockets from snapshot output configuration");
4638 ret_code = LTTNG_ERR_NOMEM;
4639 goto error;
4640 }
4641 ret_code = set_relayd_for_snapshot(
4642 snapshot_kernel_consumer_output, session);
4643 if (ret_code != LTTNG_OK) {
4644 ERR("Failed to setup relay daemon for kernel tracer snapshot");
4645 goto error;
4646 }
4647 session->kernel_session->consumer =
4648 snapshot_kernel_consumer_output;
4649 }
4650 if (session->ust_session) {
4651 original_ust_consumer_output = session->ust_session->consumer;
4652 snapshot_ust_consumer_output =
4653 consumer_copy_output(snapshot_output->consumer);
4654 strcpy(snapshot_ust_consumer_output->chunk_path,
4655 snapshot_chunk_name);
4656 ret = consumer_copy_sockets(snapshot_ust_consumer_output,
4657 original_ust_consumer_output);
4658 if (ret < 0) {
4659 ERR("Failed to copy consumer sockets from snapshot output configuration");
4660 ret_code = LTTNG_ERR_NOMEM;
4661 goto error;
4662 }
4663 ret_code = set_relayd_for_snapshot(
4664 snapshot_ust_consumer_output, session);
4665 if (ret_code != LTTNG_OK) {
4666 ERR("Failed to setup relay daemon for userspace tracer snapshot");
4667 goto error;
4668 }
4669 session->ust_session->consumer =
4670 snapshot_ust_consumer_output;
4671 }
4672
4673 snapshot_trace_chunk = session_create_new_trace_chunk(session,
4674 snapshot_kernel_consumer_output ?:
4675 snapshot_ust_consumer_output,
4676 consumer_output_get_base_path(
4677 snapshot_output->consumer),
4678 snapshot_chunk_name);
4679 if (!snapshot_trace_chunk) {
4680 ERR("Failed to create temporary trace chunk to record a snapshot of session \"%s\"",
4681 session->name);
4682 ret_code = LTTNG_ERR_CREATE_DIR_FAIL;
4683 goto error;
4684 }
4685 assert(!session->current_trace_chunk);
4686 ret = session_set_trace_chunk(session, snapshot_trace_chunk, NULL);
4687 lttng_trace_chunk_put(snapshot_trace_chunk);
4688 snapshot_trace_chunk = NULL;
4689 if (ret) {
4690 ERR("Failed to set temporary trace chunk to record a snapshot of session \"%s\"",
4691 session->name);
4692 ret_code = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
4693 goto error;
4694 }
4695
4696 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
4697 snapshot_output->max_size);
4698 if (nb_packets_per_stream < 0) {
4699 ret_code = LTTNG_ERR_MAX_SIZE_INVALID;
4700 goto error;
4701 }
4702
4703 if (session->kernel_session) {
4704 ret_code = record_kernel_snapshot(session->kernel_session,
4705 snapshot_kernel_consumer_output, session,
4706 wait, nb_packets_per_stream);
4707 if (ret_code != LTTNG_OK) {
4708 goto error;
4709 }
4710 }
4711
4712 if (session->ust_session) {
4713 ret_code = record_ust_snapshot(session->ust_session,
4714 snapshot_ust_consumer_output, session,
4715 wait, nb_packets_per_stream);
4716 if (ret_code != LTTNG_OK) {
4717 goto error;
4718 }
4719 }
4720
4721 if (session_set_trace_chunk(session, NULL, &snapshot_trace_chunk)) {
4722 ERR("Failed to release the current trace chunk of session \"%s\"",
4723 session->name);
4724 ret_code = LTTNG_ERR_UNK;
4725 }
4726
4727 if (session_close_trace_chunk(session, snapshot_trace_chunk,
4728 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION, NULL)) {
4729 /*
4730 * Don't goto end; make sure the chunk is closed for the session
4731 * to allow future snapshots.
4732 */
4733 ERR("Failed to close snapshot trace chunk of session \"%s\"",
4734 session->name);
4735 ret_code = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
4736 }
4737 error:
4738 if (original_ust_consumer_output) {
4739 session->ust_session->consumer = original_ust_consumer_output;
4740 }
4741 if (original_kernel_consumer_output) {
4742 session->kernel_session->consumer =
4743 original_kernel_consumer_output;
4744 }
4745 consumer_output_put(snapshot_ust_consumer_output);
4746 consumer_output_put(snapshot_kernel_consumer_output);
4747 return ret_code;
4748 }
4749
4750 /*
4751 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
4752 *
4753 * The wait parameter is ignored so this call always wait for the snapshot to
4754 * complete before returning.
4755 *
4756 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4757 */
4758 int cmd_snapshot_record(struct ltt_session *session,
4759 const struct lttng_snapshot_output *output, int wait)
4760 {
4761 enum lttng_error_code cmd_ret = LTTNG_OK;
4762 int ret;
4763 unsigned int snapshot_success = 0;
4764 char datetime[16];
4765 struct snapshot_output *tmp_output = NULL;
4766
4767 assert(session);
4768 assert(output);
4769
4770 DBG("Cmd snapshot record for session %s", session->name);
4771
4772 /* Get the datetime for the snapshot output directory. */
4773 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
4774 sizeof(datetime));
4775 if (!ret) {
4776 cmd_ret = LTTNG_ERR_INVALID;
4777 goto error;
4778 }
4779
4780 /*
4781 * Permission denied to create an output if the session is not
4782 * set in no output mode.
4783 */
4784 if (session->output_traces) {
4785 cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4786 goto error;
4787 }
4788
4789 /* The session needs to be started at least once. */
4790 if (!session->has_been_started) {
4791 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4792 goto error;
4793 }
4794
4795 /* Use temporary output for the session. */
4796 if (*output->ctrl_url != '\0') {
4797 tmp_output = snapshot_output_alloc();
4798 if (!tmp_output) {
4799 cmd_ret = LTTNG_ERR_NOMEM;
4800 goto error;
4801 }
4802
4803 ret = snapshot_output_init(session, output->max_size,
4804 output->name,
4805 output->ctrl_url, output->data_url,
4806 session->consumer,
4807 tmp_output, NULL);
4808 if (ret < 0) {
4809 if (ret == -ENOMEM) {
4810 cmd_ret = LTTNG_ERR_NOMEM;
4811 } else {
4812 cmd_ret = LTTNG_ERR_INVALID;
4813 }
4814 goto error;
4815 }
4816 /* Use the global session count for the temporary snapshot. */
4817 tmp_output->nb_snapshot = session->snapshot.nb_snapshot;
4818
4819 /* Use the global datetime */
4820 memcpy(tmp_output->datetime, datetime, sizeof(datetime));
4821 cmd_ret = snapshot_record(session, tmp_output, wait);
4822 if (cmd_ret != LTTNG_OK) {
4823 goto error;
4824 }
4825 snapshot_success = 1;
4826 } else {
4827 struct snapshot_output *sout;
4828 struct lttng_ht_iter iter;
4829
4830 rcu_read_lock();
4831 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
4832 &iter.iter, sout, node.node) {
4833 struct snapshot_output output_copy;
4834
4835 /*
4836 * Make a local copy of the output and override output
4837 * parameters with those provided as part of the
4838 * command.
4839 */
4840 memcpy(&output_copy, sout, sizeof(output_copy));
4841
4842 if (output->max_size != (uint64_t) -1ULL) {
4843 output_copy.max_size = output->max_size;
4844 }
4845
4846 output_copy.nb_snapshot = session->snapshot.nb_snapshot;
4847 memcpy(output_copy.datetime, datetime,
4848 sizeof(datetime));
4849
4850 /* Use temporary name. */
4851 if (*output->name != '\0') {
4852 if (lttng_strncpy(output_copy.name,
4853 output->name,
4854 sizeof(output_copy.name))) {
4855 cmd_ret = LTTNG_ERR_INVALID;
4856 rcu_read_unlock();
4857 goto error;
4858 }
4859 }
4860
4861 cmd_ret = snapshot_record(session, &output_copy, wait);
4862 if (cmd_ret != LTTNG_OK) {
4863 rcu_read_unlock();
4864 goto error;
4865 }
4866 snapshot_success = 1;
4867 }
4868 rcu_read_unlock();
4869 }
4870
4871 if (snapshot_success) {
4872 session->snapshot.nb_snapshot++;
4873 } else {
4874 cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
4875 }
4876
4877 error:
4878 if (tmp_output) {
4879 snapshot_output_destroy(tmp_output);
4880 }
4881 return cmd_ret;
4882 }
4883
4884 /*
4885 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
4886 */
4887 int cmd_set_session_shm_path(struct ltt_session *session,
4888 const char *shm_path)
4889 {
4890 /* Safety net */
4891 assert(session);
4892
4893 /*
4894 * Can only set shm path before session is started.
4895 */
4896 if (session->has_been_started) {
4897 return LTTNG_ERR_SESSION_STARTED;
4898 }
4899
4900 strncpy(session->shm_path, shm_path,
4901 sizeof(session->shm_path));
4902 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
4903
4904 return 0;
4905 }
4906
4907 /*
4908 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
4909 *
4910 * Ask the consumer to rotate the session output directory.
4911 * The session lock must be held.
4912 *
4913 * Returns LTTNG_OK on success or else a negative LTTng error code.
4914 */
4915 int cmd_rotate_session(struct ltt_session *session,
4916 struct lttng_rotate_session_return *rotate_return,
4917 bool quiet_rotation,
4918 enum lttng_trace_chunk_command_type command)
4919 {
4920 int ret;
4921 uint64_t ongoing_rotation_chunk_id;
4922 enum lttng_error_code cmd_ret = LTTNG_OK;
4923 struct lttng_trace_chunk *chunk_being_archived = NULL;
4924 struct lttng_trace_chunk *new_trace_chunk = NULL;
4925 enum lttng_trace_chunk_status chunk_status;
4926 bool failed_to_rotate = false;
4927 enum lttng_error_code rotation_fail_code = LTTNG_OK;
4928
4929 assert(session);
4930
4931 if (!session->has_been_started) {
4932 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4933 goto end;
4934 }
4935
4936 /*
4937 * Explicit rotation is not supported for live sessions.
4938 * However, live sessions can perform a quiet rotation on
4939 * destroy.
4940 * Rotation is not supported for snapshot traces (no output).
4941 */
4942 if ((!quiet_rotation && session->live_timer) ||
4943 !session->output_traces) {
4944 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
4945 goto end;
4946 }
4947
4948 /* Unsupported feature in lttng-relayd before 2.11. */
4949 if (!quiet_rotation && session->consumer->type == CONSUMER_DST_NET &&
4950 (session->consumer->relay_major_version == 2 &&
4951 session->consumer->relay_minor_version < 11)) {
4952 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
4953 goto end;
4954 }
4955
4956 /* Unsupported feature in lttng-modules before 2.8 (lack of sequence number). */
4957 if (session->kernel_session && !kernel_supports_ring_buffer_packet_sequence_number()) {
4958 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL;
4959 goto end;
4960 }
4961
4962 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
4963 DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
4964 session->name);
4965 cmd_ret = LTTNG_ERR_ROTATION_PENDING;
4966 goto end;
4967 }
4968
4969 /*
4970 * After a stop, we only allow one rotation to occur, the other ones are
4971 * useless until a new start.
4972 */
4973 if (session->rotated_after_last_stop) {
4974 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
4975 session->name);
4976 cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
4977 goto end;
4978 }
4979
4980 /*
4981 * After a stop followed by a clear, disallow following rotations a they would
4982 * generate empty chunks.
4983 */
4984 if (session->cleared_after_last_stop) {
4985 DBG("Session \"%s\" was already cleared after stop, refusing rotation",
4986 session->name);
4987 cmd_ret = LTTNG_ERR_ROTATION_AFTER_STOP_CLEAR;
4988 goto end;
4989 }
4990
4991 if (session->active) {
4992 new_trace_chunk = session_create_new_trace_chunk(session, NULL,
4993 NULL, NULL);
4994 if (!new_trace_chunk) {
4995 cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
4996 goto error;
4997 }
4998 }
4999
5000 /*
5001 * The current trace chunk becomes the chunk being archived.
5002 *
5003 * After this point, "chunk_being_archived" must absolutely
5004 * be closed on the consumer(s), otherwise it will never be
5005 * cleaned-up, which will result in a leak.
5006 */
5007 ret = session_set_trace_chunk(session, new_trace_chunk,
5008 &chunk_being_archived);
5009 if (ret) {
5010 cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
5011 goto error;
5012 }
5013
5014 if (session->kernel_session) {
5015 cmd_ret = kernel_rotate_session(session);
5016 if (cmd_ret != LTTNG_OK) {
5017 failed_to_rotate = true;
5018 rotation_fail_code = cmd_ret;
5019 }
5020 }
5021 if (session->ust_session) {
5022 cmd_ret = ust_app_rotate_session(session);
5023 if (cmd_ret != LTTNG_OK) {
5024 failed_to_rotate = true;
5025 rotation_fail_code = cmd_ret;
5026 }
5027 }
5028
5029 if (!session->active) {
5030 session->rotated_after_last_stop = true;
5031 }
5032
5033 if (!chunk_being_archived) {
5034 DBG("Rotating session \"%s\" from a \"NULL\" trace chunk to a new trace chunk, skipping completion check",
5035 session->name);
5036 if (failed_to_rotate) {
5037 cmd_ret = rotation_fail_code;
5038 goto error;
5039 }
5040 cmd_ret = LTTNG_OK;
5041 goto end;
5042 }
5043
5044 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
5045 chunk_status = lttng_trace_chunk_get_id(chunk_being_archived,
5046 &ongoing_rotation_chunk_id);
5047 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5048
5049 ret = session_close_trace_chunk(session, chunk_being_archived,
5050 command, session->last_chunk_path);
5051 if (ret) {
5052 cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5053 goto error;
5054 }
5055
5056 if (failed_to_rotate) {
5057 cmd_ret = rotation_fail_code;
5058 goto error;
5059 }
5060
5061 session->quiet_rotation = quiet_rotation;
5062 ret = timer_session_rotation_pending_check_start(session,
5063 DEFAULT_ROTATE_PENDING_TIMER);
5064 if (ret) {
5065 cmd_ret = LTTNG_ERR_UNK;
5066 goto error;
5067 }
5068
5069 if (rotate_return) {
5070 rotate_return->rotation_id = ongoing_rotation_chunk_id;
5071 }
5072
5073 session->chunk_being_archived = chunk_being_archived;
5074 chunk_being_archived = NULL;
5075 if (!quiet_rotation) {
5076 ret = notification_thread_command_session_rotation_ongoing(
5077 notification_thread_handle,
5078 session->name, session->uid, session->gid,
5079 ongoing_rotation_chunk_id);
5080 if (ret != LTTNG_OK) {
5081 ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
5082 session->name);
5083 cmd_ret = ret;
5084 }
5085 }
5086
5087 DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
5088 session->name, ongoing_rotation_chunk_id);
5089 end:
5090 lttng_trace_chunk_put(new_trace_chunk);
5091 lttng_trace_chunk_put(chunk_being_archived);
5092 ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
5093 return ret;
5094 error:
5095 if (session_reset_rotation_state(session,
5096 LTTNG_ROTATION_STATE_ERROR)) {
5097 ERR("Failed to reset rotation state of session \"%s\"",
5098 session->name);
5099 }
5100 goto end;
5101 }
5102
5103 /*
5104 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
5105 *
5106 * Check if the session has finished its rotation.
5107 *
5108 * Return LTTNG_OK on success or else an LTTNG_ERR code.
5109 */
5110 int cmd_rotate_get_info(struct ltt_session *session,
5111 struct lttng_rotation_get_info_return *info_return,
5112 uint64_t rotation_id)
5113 {
5114 enum lttng_error_code cmd_ret = LTTNG_OK;
5115 enum lttng_rotation_state rotation_state;
5116
5117 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
5118 session->most_recent_chunk_id.value);
5119
5120 if (session->chunk_being_archived) {
5121 enum lttng_trace_chunk_status chunk_status;
5122 uint64_t chunk_id;
5123
5124 chunk_status = lttng_trace_chunk_get_id(
5125 session->chunk_being_archived,
5126 &chunk_id);
5127 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5128
5129 rotation_state = rotation_id == chunk_id ?
5130 LTTNG_ROTATION_STATE_ONGOING :
5131 LTTNG_ROTATION_STATE_EXPIRED;
5132 } else {
5133 if (session->last_archived_chunk_id.is_set &&
5134 rotation_id != session->last_archived_chunk_id.value) {
5135 rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
5136 } else {
5137 rotation_state = session->rotation_state;
5138 }
5139 }
5140
5141 switch (rotation_state) {
5142 case LTTNG_ROTATION_STATE_NO_ROTATION:
5143 DBG("Reporting that no rotation has occurred within the lifetime of session \"%s\"",
5144 session->name);
5145 goto end;
5146 case LTTNG_ROTATION_STATE_EXPIRED:
5147 DBG("Reporting that the rotation state of rotation id %" PRIu64 " of session \"%s\" has expired",
5148 rotation_id, session->name);
5149 break;
5150 case LTTNG_ROTATION_STATE_ONGOING:
5151 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
5152 rotation_id, session->name);
5153 break;
5154 case LTTNG_ROTATION_STATE_COMPLETED:
5155 {
5156 int fmt_ret;
5157 char *chunk_path;
5158 char *current_tracing_path_reply;
5159 size_t current_tracing_path_reply_len;
5160
5161 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
5162 rotation_id, session->name);
5163
5164 switch (session_get_consumer_destination_type(session)) {
5165 case CONSUMER_DST_LOCAL:
5166 current_tracing_path_reply =
5167 info_return->location.local.absolute_path;
5168 current_tracing_path_reply_len =
5169 sizeof(info_return->location.local.absolute_path);
5170 info_return->location_type =
5171 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
5172 fmt_ret = asprintf(&chunk_path,
5173 "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
5174 session_get_base_path(session),
5175 session->last_archived_chunk_name);
5176 if (fmt_ret == -1) {
5177 PERROR("Failed to format the path of the last archived trace chunk");
5178 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5179 cmd_ret = LTTNG_ERR_UNK;
5180 goto end;
5181 }
5182 break;
5183 case CONSUMER_DST_NET:
5184 {
5185 uint16_t ctrl_port, data_port;
5186
5187 current_tracing_path_reply =
5188 info_return->location.relay.relative_path;
5189 current_tracing_path_reply_len =
5190 sizeof(info_return->location.relay.relative_path);
5191 /* Currently the only supported relay protocol. */
5192 info_return->location.relay.protocol =
5193 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
5194
5195 fmt_ret = lttng_strncpy(info_return->location.relay.host,
5196 session_get_net_consumer_hostname(session),
5197 sizeof(info_return->location.relay.host));
5198 if (fmt_ret) {
5199 ERR("Failed to copy host name to rotate_get_info reply");
5200 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5201 cmd_ret = LTTNG_ERR_SET_URL;
5202 goto end;
5203 }
5204
5205 session_get_net_consumer_ports(session, &ctrl_port, &data_port);
5206 info_return->location.relay.ports.control = ctrl_port;
5207 info_return->location.relay.ports.data = data_port;
5208 info_return->location_type =
5209 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
5210 chunk_path = strdup(session->last_chunk_path);
5211 if (!chunk_path) {
5212 ERR("Failed to allocate the path of the last archived trace chunk");
5213 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5214 cmd_ret = LTTNG_ERR_UNK;
5215 goto end;
5216 }
5217 break;
5218 }
5219 default:
5220 abort();
5221 }
5222
5223 fmt_ret = lttng_strncpy(current_tracing_path_reply,
5224 chunk_path, current_tracing_path_reply_len);
5225 free(chunk_path);
5226 if (fmt_ret) {
5227 ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
5228 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5229 cmd_ret = LTTNG_ERR_UNK;
5230 goto end;
5231 }
5232
5233 break;
5234 }
5235 case LTTNG_ROTATION_STATE_ERROR:
5236 DBG("Reporting that an error occurred during rotation %" PRIu64 " of session \"%s\"",
5237 rotation_id, session->name);
5238 break;
5239 default:
5240 abort();
5241 }
5242
5243 cmd_ret = LTTNG_OK;
5244 end:
5245 info_return->status = (int32_t) rotation_state;
5246 return cmd_ret;
5247 }
5248
5249 /*
5250 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
5251 *
5252 * Configure the automatic rotation parameters.
5253 * 'activate' to true means activate the rotation schedule type with 'new_value'.
5254 * 'activate' to false means deactivate the rotation schedule and validate that
5255 * 'new_value' has the same value as the currently active value.
5256 *
5257 * Return 0 on success or else a positive LTTNG_ERR code.
5258 */
5259 int cmd_rotation_set_schedule(struct ltt_session *session,
5260 bool activate, enum lttng_rotation_schedule_type schedule_type,
5261 uint64_t new_value,
5262 struct notification_thread_handle *notification_thread_handle)
5263 {
5264 int ret;
5265 uint64_t *parameter_value;
5266
5267 assert(session);
5268
5269 DBG("Cmd rotate set schedule session %s", session->name);
5270
5271 if (session->live_timer || !session->output_traces) {
5272 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
5273 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5274 goto end;
5275 }
5276
5277 switch (schedule_type) {
5278 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5279 parameter_value = &session->rotate_size;
5280 break;
5281 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5282 parameter_value = &session->rotate_timer_period;
5283 if (new_value >= UINT_MAX) {
5284 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
5285 new_value, UINT_MAX);
5286 ret = LTTNG_ERR_INVALID;
5287 goto end;
5288 }
5289 break;
5290 default:
5291 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
5292 ret = LTTNG_ERR_INVALID;
5293 goto end;
5294 }
5295
5296 /* Improper use of the API. */
5297 if (new_value == -1ULL) {
5298 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
5299 ret = LTTNG_ERR_INVALID;
5300 goto end;
5301 }
5302
5303 /*
5304 * As indicated in struct ltt_session's comments, a value of == 0 means
5305 * this schedule rotation type is not in use.
5306 *
5307 * Reject the command if we were asked to activate a schedule that was
5308 * already active.
5309 */
5310 if (activate && *parameter_value != 0) {
5311 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
5312 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
5313 goto end;
5314 }
5315
5316 /*
5317 * Reject the command if we were asked to deactivate a schedule that was
5318 * not active.
5319 */
5320 if (!activate && *parameter_value == 0) {
5321 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
5322 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5323 goto end;
5324 }
5325
5326 /*
5327 * Reject the command if we were asked to deactivate a schedule that
5328 * doesn't exist.
5329 */
5330 if (!activate && *parameter_value != new_value) {
5331 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
5332 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5333 goto end;
5334 }
5335
5336 *parameter_value = activate ? new_value : 0;
5337
5338 switch (schedule_type) {
5339 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5340 if (activate && session->active) {
5341 /*
5342 * Only start the timer if the session is active,
5343 * otherwise it will be started when the session starts.
5344 */
5345 ret = timer_session_rotation_schedule_timer_start(
5346 session, new_value);
5347 if (ret) {
5348 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
5349 ret = LTTNG_ERR_UNK;
5350 goto end;
5351 }
5352 } else {
5353 ret = timer_session_rotation_schedule_timer_stop(
5354 session);
5355 if (ret) {
5356 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
5357 ret = LTTNG_ERR_UNK;
5358 goto end;
5359 }
5360 }
5361 break;
5362 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5363 if (activate) {
5364 ret = subscribe_session_consumed_size_rotation(session,
5365 new_value, notification_thread_handle);
5366 if (ret) {
5367 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
5368 ret = LTTNG_ERR_UNK;
5369 goto end;
5370 }
5371 } else {
5372 ret = unsubscribe_session_consumed_size_rotation(session,
5373 notification_thread_handle);
5374 if (ret) {
5375 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
5376 ret = LTTNG_ERR_UNK;
5377 goto end;
5378 }
5379
5380 }
5381 break;
5382 default:
5383 /* Would have been caught before. */
5384 abort();
5385 }
5386
5387 ret = LTTNG_OK;
5388
5389 goto end;
5390
5391 end:
5392 return ret;
5393 }
5394
5395 /* Wait for a given path to be removed before continuing. */
5396 static enum lttng_error_code wait_on_path(void *path_data)
5397 {
5398 const char *shm_path = path_data;
5399
5400 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5401 shm_path);
5402 while (true) {
5403 int ret;
5404 struct stat st;
5405
5406 ret = stat(shm_path, &st);
5407 if (ret) {
5408 if (errno != ENOENT) {
5409 PERROR("stat() returned an error while checking for the existence of the shm path");
5410 } else {
5411 DBG("shm path no longer exists, completing the destruction of session");
5412 }
5413 break;
5414 } else {
5415 if (!S_ISDIR(st.st_mode)) {
5416 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5417 shm_path);
5418 break;
5419 }
5420 }
5421 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
5422 }
5423 return LTTNG_OK;
5424 }
5425
5426 /*
5427 * Returns a pointer to a handler to run on completion of a command.
5428 * Returns NULL if no handler has to be run for the last command executed.
5429 */
5430 const struct cmd_completion_handler *cmd_pop_completion_handler(void)
5431 {
5432 struct cmd_completion_handler *handler = current_completion_handler;
5433
5434 current_completion_handler = NULL;
5435 return handler;
5436 }
5437
5438 /*
5439 * Init command subsystem.
5440 */
5441 void cmd_init(void)
5442 {
5443 /*
5444 * Set network sequence index to 1 for streams to match a relayd
5445 * socket on the consumer side.
5446 */
5447 pthread_mutex_lock(&relayd_net_seq_idx_lock);
5448 relayd_net_seq_idx = 1;
5449 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
5450
5451 DBG("Command subsystem initialized");
5452 }
LTTng tools - Deliverables
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