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