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sessiond: query relayd configuration for availability of clear feature
[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c
1 /*
2 * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
3 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License, version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 51
16 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #define _LGPL_SOURCE
20 #include <assert.h>
21 #include <inttypes.h>
22 #include <urcu/list.h>
23 #include <urcu/uatomic.h>
24 #include <sys/stat.h>
25 #include <stdio.h>
26
27 #include <common/defaults.h>
28 #include <common/common.h>
29 #include <common/sessiond-comm/sessiond-comm.h>
30 #include <common/relayd/relayd.h>
31 #include <common/utils.h>
32 #include <common/compat/string.h>
33 #include <common/kernel-ctl/kernel-ctl.h>
34 #include <common/dynamic-buffer.h>
35 #include <common/buffer-view.h>
36 #include <common/trace-chunk.h>
37 #include <lttng/location-internal.h>
38 #include <lttng/trigger/trigger-internal.h>
39 #include <lttng/condition/condition.h>
40 #include <lttng/action/action.h>
41 #include <lttng/channel.h>
42 #include <lttng/channel-internal.h>
43 #include <lttng/rotate-internal.h>
44 #include <lttng/location-internal.h>
45 #include <lttng/session-internal.h>
46 #include <lttng/userspace-probe-internal.h>
47 #include <lttng/session-descriptor-internal.h>
48 #include <common/string-utils/string-utils.h>
49
50 #include "channel.h"
51 #include "consumer.h"
52 #include "event.h"
53 #include "health-sessiond.h"
54 #include "kernel.h"
55 #include "kernel-consumer.h"
56 #include "lttng-sessiond.h"
57 #include "utils.h"
58 #include "lttng-syscall.h"
59 #include "agent.h"
60 #include "buffer-registry.h"
61 #include "notification-thread.h"
62 #include "notification-thread-commands.h"
63 #include "rotate.h"
64 #include "rotation-thread.h"
65 #include "timer.h"
66 #include "agent-thread.h"
67
68 #include "cmd.h"
69
70 /* Sleep for 100ms between each check for the shm path's deletion. */
71 #define SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US 100000
72
73 struct cmd_destroy_session_reply_context {
74 int reply_sock_fd;
75 bool implicit_rotation_on_destroy;
76 /*
77 * Indicates whether or not an error occurred while launching the
78 * destruction of a session.
79 */
80 enum lttng_error_code destruction_status;
81 };
82
83 static enum lttng_error_code wait_on_path(void *path);
84
85 /*
86 * Command completion handler that is used by the destroy command
87 * when a session that has a non-default shm_path is being destroyed.
88 *
89 * See comment in cmd_destroy_session() for the rationale.
90 */
91 static struct destroy_completion_handler {
92 struct cmd_completion_handler handler;
93 char shm_path[member_sizeof(struct ltt_session, shm_path)];
94 } destroy_completion_handler = {
95 .handler = {
96 .run = wait_on_path,
97 .data = destroy_completion_handler.shm_path
98 },
99 .shm_path = { 0 },
100 };
101
102 static struct cmd_completion_handler *current_completion_handler;
103
104 /*
105 * Used to keep a unique index for each relayd socket created where this value
106 * is associated with streams on the consumer so it can match the right relayd
107 * to send to. It must be accessed with the relayd_net_seq_idx_lock
108 * held.
109 */
110 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
111 static uint64_t relayd_net_seq_idx;
112
113 static int validate_ust_event_name(const char *);
114 static int cmd_enable_event_internal(struct ltt_session *session,
115 const struct lttng_domain *domain,
116 char *channel_name, struct lttng_event *event,
117 char *filter_expression,
118 struct lttng_filter_bytecode *filter,
119 struct lttng_event_exclusion *exclusion,
120 int wpipe);
121
122 /*
123 * Create a session path used by list_lttng_sessions for the case that the
124 * session consumer is on the network.
125 */
126 static int build_network_session_path(char *dst, size_t size,
127 struct ltt_session *session)
128 {
129 int ret, kdata_port, udata_port;
130 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
131 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
132
133 assert(session);
134 assert(dst);
135
136 memset(tmp_urls, 0, sizeof(tmp_urls));
137 memset(tmp_uurl, 0, sizeof(tmp_uurl));
138
139 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
140
141 if (session->kernel_session && session->kernel_session->consumer) {
142 kuri = &session->kernel_session->consumer->dst.net.control;
143 kdata_port = session->kernel_session->consumer->dst.net.data.port;
144 }
145
146 if (session->ust_session && session->ust_session->consumer) {
147 uuri = &session->ust_session->consumer->dst.net.control;
148 udata_port = session->ust_session->consumer->dst.net.data.port;
149 }
150
151 if (uuri == NULL && kuri == NULL) {
152 uri = &session->consumer->dst.net.control;
153 kdata_port = session->consumer->dst.net.data.port;
154 } else if (kuri && uuri) {
155 ret = uri_compare(kuri, uuri);
156 if (ret) {
157 /* Not Equal */
158 uri = kuri;
159 /* Build uuri URL string */
160 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
161 if (ret < 0) {
162 goto error;
163 }
164 } else {
165 uri = kuri;
166 }
167 } else if (kuri && uuri == NULL) {
168 uri = kuri;
169 } else if (uuri && kuri == NULL) {
170 uri = uuri;
171 }
172
173 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
174 if (ret < 0) {
175 goto error;
176 }
177
178 /*
179 * Do we have a UST url set. If yes, this means we have both kernel and UST
180 * to print.
181 */
182 if (*tmp_uurl != '\0') {
183 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
184 tmp_urls, kdata_port, tmp_uurl, udata_port);
185 } else {
186 int dport;
187 if (kuri || (!kuri && !uuri)) {
188 dport = kdata_port;
189 } else {
190 /* No kernel URI, use the UST port. */
191 dport = udata_port;
192 }
193 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
194 }
195
196 error:
197 return ret;
198 }
199
200 /*
201 * Get run-time attributes if the session has been started (discarded events,
202 * lost packets).
203 */
204 static int get_kernel_runtime_stats(struct ltt_session *session,
205 struct ltt_kernel_channel *kchan, uint64_t *discarded_events,
206 uint64_t *lost_packets)
207 {
208 int ret;
209
210 if (!session->has_been_started) {
211 ret = 0;
212 *discarded_events = 0;
213 *lost_packets = 0;
214 goto end;
215 }
216
217 ret = consumer_get_discarded_events(session->id, kchan->key,
218 session->kernel_session->consumer,
219 discarded_events);
220 if (ret < 0) {
221 goto end;
222 }
223
224 ret = consumer_get_lost_packets(session->id, kchan->key,
225 session->kernel_session->consumer,
226 lost_packets);
227 if (ret < 0) {
228 goto end;
229 }
230
231 end:
232 return ret;
233 }
234
235 /*
236 * Get run-time attributes if the session has been started (discarded events,
237 * lost packets).
238 */
239 static int get_ust_runtime_stats(struct ltt_session *session,
240 struct ltt_ust_channel *uchan, uint64_t *discarded_events,
241 uint64_t *lost_packets)
242 {
243 int ret;
244 struct ltt_ust_session *usess;
245
246 if (!discarded_events || !lost_packets) {
247 ret = -1;
248 goto end;
249 }
250
251 usess = session->ust_session;
252 assert(discarded_events);
253 assert(lost_packets);
254
255 if (!usess || !session->has_been_started) {
256 *discarded_events = 0;
257 *lost_packets = 0;
258 ret = 0;
259 goto end;
260 }
261
262 if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
263 ret = ust_app_uid_get_channel_runtime_stats(usess->id,
264 &usess->buffer_reg_uid_list,
265 usess->consumer, uchan->id,
266 uchan->attr.overwrite,
267 discarded_events,
268 lost_packets);
269 } else if (usess->buffer_type == LTTNG_BUFFER_PER_PID) {
270 ret = ust_app_pid_get_channel_runtime_stats(usess,
271 uchan, usess->consumer,
272 uchan->attr.overwrite,
273 discarded_events,
274 lost_packets);
275 if (ret < 0) {
276 goto end;
277 }
278 *discarded_events += uchan->per_pid_closed_app_discarded;
279 *lost_packets += uchan->per_pid_closed_app_lost;
280 } else {
281 ERR("Unsupported buffer type");
282 assert(0);
283 ret = -1;
284 goto end;
285 }
286
287 end:
288 return ret;
289 }
290
291 /*
292 * Fill lttng_channel array of all channels.
293 */
294 static ssize_t list_lttng_channels(enum lttng_domain_type domain,
295 struct ltt_session *session, struct lttng_channel *channels,
296 struct lttng_channel_extended *chan_exts)
297 {
298 int i = 0, ret = 0;
299 struct ltt_kernel_channel *kchan;
300
301 DBG("Listing channels for session %s", session->name);
302
303 switch (domain) {
304 case LTTNG_DOMAIN_KERNEL:
305 /* Kernel channels */
306 if (session->kernel_session != NULL) {
307 cds_list_for_each_entry(kchan,
308 &session->kernel_session->channel_list.head, list) {
309 uint64_t discarded_events, lost_packets;
310 struct lttng_channel_extended *extended;
311
312 extended = (struct lttng_channel_extended *)
313 kchan->channel->attr.extended.ptr;
314
315 ret = get_kernel_runtime_stats(session, kchan,
316 &discarded_events, &lost_packets);
317 if (ret < 0) {
318 goto end;
319 }
320 /* Copy lttng_channel struct to array */
321 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
322 channels[i].enabled = kchan->enabled;
323 chan_exts[i].discarded_events =
324 discarded_events;
325 chan_exts[i].lost_packets = lost_packets;
326 chan_exts[i].monitor_timer_interval =
327 extended->monitor_timer_interval;
328 chan_exts[i].blocking_timeout = 0;
329 i++;
330 }
331 }
332 break;
333 case LTTNG_DOMAIN_UST:
334 {
335 struct lttng_ht_iter iter;
336 struct ltt_ust_channel *uchan;
337
338 rcu_read_lock();
339 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
340 &iter.iter, uchan, node.node) {
341 uint64_t discarded_events = 0, lost_packets = 0;
342
343 if (lttng_strncpy(channels[i].name, uchan->name,
344 LTTNG_SYMBOL_NAME_LEN)) {
345 break;
346 }
347 channels[i].attr.overwrite = uchan->attr.overwrite;
348 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
349 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
350 channels[i].attr.switch_timer_interval =
351 uchan->attr.switch_timer_interval;
352 channels[i].attr.read_timer_interval =
353 uchan->attr.read_timer_interval;
354 channels[i].enabled = uchan->enabled;
355 channels[i].attr.tracefile_size = uchan->tracefile_size;
356 channels[i].attr.tracefile_count = uchan->tracefile_count;
357
358 /*
359 * Map enum lttng_ust_output to enum lttng_event_output.
360 */
361 switch (uchan->attr.output) {
362 case LTTNG_UST_MMAP:
363 channels[i].attr.output = LTTNG_EVENT_MMAP;
364 break;
365 default:
366 /*
367 * LTTNG_UST_MMAP is the only supported UST
368 * output mode.
369 */
370 assert(0);
371 break;
372 }
373
374 chan_exts[i].monitor_timer_interval =
375 uchan->monitor_timer_interval;
376 chan_exts[i].blocking_timeout =
377 uchan->attr.u.s.blocking_timeout;
378
379 ret = get_ust_runtime_stats(session, uchan,
380 &discarded_events, &lost_packets);
381 if (ret < 0) {
382 break;
383 }
384 chan_exts[i].discarded_events = discarded_events;
385 chan_exts[i].lost_packets = lost_packets;
386 i++;
387 }
388 rcu_read_unlock();
389 break;
390 }
391 default:
392 break;
393 }
394
395 end:
396 if (ret < 0) {
397 return -LTTNG_ERR_FATAL;
398 } else {
399 return LTTNG_OK;
400 }
401 }
402
403 static int increment_extended_len(const char *filter_expression,
404 struct lttng_event_exclusion *exclusion,
405 const struct lttng_userspace_probe_location *probe_location,
406 size_t *extended_len)
407 {
408 int ret = 0;
409
410 *extended_len += sizeof(struct lttcomm_event_extended_header);
411
412 if (filter_expression) {
413 *extended_len += strlen(filter_expression) + 1;
414 }
415
416 if (exclusion) {
417 *extended_len += exclusion->count * LTTNG_SYMBOL_NAME_LEN;
418 }
419
420 if (probe_location) {
421 ret = lttng_userspace_probe_location_serialize(probe_location,
422 NULL, NULL);
423 if (ret < 0) {
424 goto end;
425 }
426 *extended_len += ret;
427 }
428 ret = 0;
429 end:
430 return ret;
431 }
432
433 static int append_extended_info(const char *filter_expression,
434 struct lttng_event_exclusion *exclusion,
435 struct lttng_userspace_probe_location *probe_location,
436 void **extended_at)
437 {
438 int ret = 0;
439 size_t filter_len = 0;
440 size_t nb_exclusions = 0;
441 size_t userspace_probe_location_len = 0;
442 struct lttng_dynamic_buffer location_buffer;
443 struct lttcomm_event_extended_header extended_header;
444
445 if (filter_expression) {
446 filter_len = strlen(filter_expression) + 1;
447 }
448
449 if (exclusion) {
450 nb_exclusions = exclusion->count;
451 }
452
453 if (probe_location) {
454 lttng_dynamic_buffer_init(&location_buffer);
455 ret = lttng_userspace_probe_location_serialize(probe_location,
456 &location_buffer, NULL);
457 if (ret < 0) {
458 ret = -1;
459 goto end;
460 }
461 userspace_probe_location_len = location_buffer.size;
462 }
463
464 /* Set header fields */
465 extended_header.filter_len = filter_len;
466 extended_header.nb_exclusions = nb_exclusions;
467 extended_header.userspace_probe_location_len = userspace_probe_location_len;
468
469 /* Copy header */
470 memcpy(*extended_at, &extended_header, sizeof(extended_header));
471 *extended_at += sizeof(extended_header);
472
473 /* Copy filter string */
474 if (filter_expression) {
475 memcpy(*extended_at, filter_expression, filter_len);
476 *extended_at += filter_len;
477 }
478
479 /* Copy exclusion names */
480 if (exclusion) {
481 size_t len = nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
482
483 memcpy(*extended_at, &exclusion->names, len);
484 *extended_at += len;
485 }
486
487 if (probe_location) {
488 memcpy(*extended_at, location_buffer.data, location_buffer.size);
489 *extended_at += location_buffer.size;
490 lttng_dynamic_buffer_reset(&location_buffer);
491 }
492 ret = 0;
493 end:
494 return ret;
495 }
496
497 /*
498 * Create a list of agent domain events.
499 *
500 * Return number of events in list on success or else a negative value.
501 */
502 static int list_lttng_agent_events(struct agent *agt,
503 struct lttng_event **events, size_t *total_size)
504 {
505 int i = 0, ret = 0;
506 unsigned int nb_event = 0;
507 struct agent_event *event;
508 struct lttng_event *tmp_events = NULL;
509 struct lttng_ht_iter iter;
510 size_t extended_len = 0;
511 void *extended_at;
512
513 assert(agt);
514 assert(events);
515
516 DBG3("Listing agent events");
517
518 rcu_read_lock();
519 nb_event = lttng_ht_get_count(agt->events);
520 rcu_read_unlock();
521 if (nb_event == 0) {
522 ret = nb_event;
523 *total_size = 0;
524 goto error;
525 }
526
527 /* Compute required extended infos size */
528 extended_len = nb_event * sizeof(struct lttcomm_event_extended_header);
529
530 /*
531 * This is only valid because the commands which add events are
532 * processed in the same thread as the listing.
533 */
534 rcu_read_lock();
535 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
536 ret = increment_extended_len(event->filter_expression, NULL, NULL,
537 &extended_len);
538 if (ret) {
539 DBG("Error computing the length of extended info message");
540 ret = -LTTNG_ERR_FATAL;
541 goto error;
542 }
543 }
544 rcu_read_unlock();
545
546 *total_size = nb_event * sizeof(*tmp_events) + extended_len;
547 tmp_events = zmalloc(*total_size);
548 if (!tmp_events) {
549 PERROR("zmalloc agent events session");
550 ret = -LTTNG_ERR_FATAL;
551 goto error;
552 }
553
554 extended_at = ((uint8_t *) tmp_events) +
555 nb_event * sizeof(struct lttng_event);
556
557 rcu_read_lock();
558 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
559 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
560 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
561 tmp_events[i].enabled = event->enabled;
562 tmp_events[i].loglevel = event->loglevel_value;
563 tmp_events[i].loglevel_type = event->loglevel_type;
564 i++;
565
566 /* Append extended info */
567 ret = append_extended_info(event->filter_expression, NULL, NULL,
568 &extended_at);
569 if (ret) {
570 DBG("Error appending extended info message");
571 ret = -LTTNG_ERR_FATAL;
572 goto error;
573 }
574 }
575
576 *events = tmp_events;
577 ret = nb_event;
578 assert(nb_event == i);
579
580 end:
581 rcu_read_unlock();
582 return ret;
583 error:
584 free(tmp_events);
585 goto end;
586 }
587
588 /*
589 * Create a list of ust global domain events.
590 */
591 static int list_lttng_ust_global_events(char *channel_name,
592 struct ltt_ust_domain_global *ust_global,
593 struct lttng_event **events, size_t *total_size)
594 {
595 int i = 0, ret = 0;
596 unsigned int nb_event = 0;
597 struct lttng_ht_iter iter;
598 struct lttng_ht_node_str *node;
599 struct ltt_ust_channel *uchan;
600 struct ltt_ust_event *uevent;
601 struct lttng_event *tmp;
602 size_t extended_len = 0;
603 void *extended_at;
604
605 DBG("Listing UST global events for channel %s", channel_name);
606
607 rcu_read_lock();
608
609 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
610 node = lttng_ht_iter_get_node_str(&iter);
611 if (node == NULL) {
612 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
613 goto end;
614 }
615
616 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
617
618 nb_event = lttng_ht_get_count(uchan->events);
619 if (nb_event == 0) {
620 ret = nb_event;
621 *total_size = 0;
622 goto end;
623 }
624
625 DBG3("Listing UST global %d events", nb_event);
626
627 /* Compute required extended infos size */
628 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
629 if (uevent->internal) {
630 nb_event--;
631 continue;
632 }
633
634 ret = increment_extended_len(uevent->filter_expression,
635 uevent->exclusion, NULL, &extended_len);
636 if (ret) {
637 DBG("Error computing the length of extended info message");
638 ret = -LTTNG_ERR_FATAL;
639 goto end;
640 }
641 }
642 if (nb_event == 0) {
643 /* All events are internal, skip. */
644 ret = 0;
645 *total_size = 0;
646 goto end;
647 }
648
649 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
650 tmp = zmalloc(*total_size);
651 if (tmp == NULL) {
652 ret = -LTTNG_ERR_FATAL;
653 goto end;
654 }
655
656 extended_at = ((uint8_t *) tmp) + nb_event * sizeof(struct lttng_event);
657
658 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
659 if (uevent->internal) {
660 /* This event should remain hidden from clients */
661 continue;
662 }
663 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
664 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
665 tmp[i].enabled = uevent->enabled;
666
667 switch (uevent->attr.instrumentation) {
668 case LTTNG_UST_TRACEPOINT:
669 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
670 break;
671 case LTTNG_UST_PROBE:
672 tmp[i].type = LTTNG_EVENT_PROBE;
673 break;
674 case LTTNG_UST_FUNCTION:
675 tmp[i].type = LTTNG_EVENT_FUNCTION;
676 break;
677 }
678
679 tmp[i].loglevel = uevent->attr.loglevel;
680 switch (uevent->attr.loglevel_type) {
681 case LTTNG_UST_LOGLEVEL_ALL:
682 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
683 break;
684 case LTTNG_UST_LOGLEVEL_RANGE:
685 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
686 break;
687 case LTTNG_UST_LOGLEVEL_SINGLE:
688 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
689 break;
690 }
691 if (uevent->filter) {
692 tmp[i].filter = 1;
693 }
694 if (uevent->exclusion) {
695 tmp[i].exclusion = 1;
696 }
697 i++;
698
699 /* Append extended info */
700 ret = append_extended_info(uevent->filter_expression,
701 uevent->exclusion, NULL, &extended_at);
702 if (ret) {
703 DBG("Error appending extended info message");
704 ret = -LTTNG_ERR_FATAL;
705 goto end;
706 }
707 }
708
709 ret = nb_event;
710 *events = tmp;
711 end:
712 rcu_read_unlock();
713 return ret;
714 }
715
716 /*
717 * Fill lttng_event array of all kernel events in the channel.
718 */
719 static int list_lttng_kernel_events(char *channel_name,
720 struct ltt_kernel_session *kernel_session,
721 struct lttng_event **events, size_t *total_size)
722 {
723 int i = 0, ret;
724 unsigned int nb_event;
725 struct ltt_kernel_event *event;
726 struct ltt_kernel_channel *kchan;
727 size_t extended_len = 0;
728 void *extended_at;
729
730 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
731 if (kchan == NULL) {
732 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
733 goto error;
734 }
735
736 nb_event = kchan->event_count;
737
738 DBG("Listing events for channel %s", kchan->channel->name);
739
740 if (nb_event == 0) {
741 *total_size = 0;
742 *events = NULL;
743 goto end;
744 }
745
746 /* Compute required extended infos size */
747 cds_list_for_each_entry(event, &kchan->events_list.head, list) {
748 ret = increment_extended_len(event->filter_expression, NULL,
749 event->userspace_probe_location,
750 &extended_len);
751 if (ret) {
752 DBG("Error computing the length of extended info message");
753 ret = -LTTNG_ERR_FATAL;
754 goto error;
755 }
756 }
757
758 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
759 *events = zmalloc(*total_size);
760 if (*events == NULL) {
761 ret = -LTTNG_ERR_FATAL;
762 goto error;
763 }
764
765 extended_at = ((void *) *events) +
766 nb_event * sizeof(struct lttng_event);
767
768 /* Kernel channels */
769 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
770 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
771 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
772 (*events)[i].enabled = event->enabled;
773 (*events)[i].filter =
774 (unsigned char) !!event->filter_expression;
775
776 switch (event->event->instrumentation) {
777 case LTTNG_KERNEL_TRACEPOINT:
778 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
779 break;
780 case LTTNG_KERNEL_KRETPROBE:
781 (*events)[i].type = LTTNG_EVENT_FUNCTION;
782 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
783 sizeof(struct lttng_kernel_kprobe));
784 break;
785 case LTTNG_KERNEL_KPROBE:
786 (*events)[i].type = LTTNG_EVENT_PROBE;
787 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
788 sizeof(struct lttng_kernel_kprobe));
789 break;
790 case LTTNG_KERNEL_UPROBE:
791 (*events)[i].type = LTTNG_EVENT_USERSPACE_PROBE;
792 break;
793 case LTTNG_KERNEL_FUNCTION:
794 (*events)[i].type = LTTNG_EVENT_FUNCTION;
795 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
796 sizeof(struct lttng_kernel_function));
797 break;
798 case LTTNG_KERNEL_NOOP:
799 (*events)[i].type = LTTNG_EVENT_NOOP;
800 break;
801 case LTTNG_KERNEL_SYSCALL:
802 (*events)[i].type = LTTNG_EVENT_SYSCALL;
803 break;
804 case LTTNG_KERNEL_ALL:
805 /* fall-through. */
806 default:
807 assert(0);
808 break;
809 }
810 i++;
811
812 /* Append extended info */
813 ret = append_extended_info(event->filter_expression, NULL,
814 event->userspace_probe_location, &extended_at);
815 if (ret) {
816 DBG("Error appending extended info message");
817 ret = -LTTNG_ERR_FATAL;
818 goto error;
819 }
820 }
821
822 end:
823 return nb_event;
824
825 error:
826 /* Negate the error code to differentiate the size from an error */
827 return -ret;
828 }
829
830 /*
831 * Add URI so the consumer output object. Set the correct path depending on the
832 * domain adding the default trace directory.
833 */
834 static enum lttng_error_code add_uri_to_consumer(
835 const struct ltt_session *session,
836 struct consumer_output *consumer,
837 struct lttng_uri *uri, enum lttng_domain_type domain)
838 {
839 int ret;
840 enum lttng_error_code ret_code = LTTNG_OK;
841
842 assert(uri);
843
844 if (consumer == NULL) {
845 DBG("No consumer detected. Don't add URI. Stopping.");
846 ret_code = LTTNG_ERR_NO_CONSUMER;
847 goto error;
848 }
849
850 switch (domain) {
851 case LTTNG_DOMAIN_KERNEL:
852 ret = lttng_strncpy(consumer->domain_subdir,
853 DEFAULT_KERNEL_TRACE_DIR,
854 sizeof(consumer->domain_subdir));
855 break;
856 case LTTNG_DOMAIN_UST:
857 ret = lttng_strncpy(consumer->domain_subdir,
858 DEFAULT_UST_TRACE_DIR,
859 sizeof(consumer->domain_subdir));
860 break;
861 default:
862 /*
863 * This case is possible is we try to add the URI to the global
864 * tracing session consumer object which in this case there is
865 * no subdir.
866 */
867 memset(consumer->domain_subdir, 0,
868 sizeof(consumer->domain_subdir));
869 ret = 0;
870 }
871 if (ret) {
872 ERR("Failed to initialize consumer output domain subdirectory");
873 ret_code = LTTNG_ERR_FATAL;
874 goto error;
875 }
876
877 switch (uri->dtype) {
878 case LTTNG_DST_IPV4:
879 case LTTNG_DST_IPV6:
880 DBG2("Setting network URI to consumer");
881
882 if (consumer->type == CONSUMER_DST_NET) {
883 if ((uri->stype == LTTNG_STREAM_CONTROL &&
884 consumer->dst.net.control_isset) ||
885 (uri->stype == LTTNG_STREAM_DATA &&
886 consumer->dst.net.data_isset)) {
887 ret_code = LTTNG_ERR_URL_EXIST;
888 goto error;
889 }
890 } else {
891 memset(&consumer->dst, 0, sizeof(consumer->dst));
892 }
893
894 /* Set URI into consumer output object */
895 ret = consumer_set_network_uri(session, consumer, uri);
896 if (ret < 0) {
897 ret_code = -ret;
898 goto error;
899 } else if (ret == 1) {
900 /*
901 * URI was the same in the consumer so we do not append the subdir
902 * again so to not duplicate output dir.
903 */
904 ret_code = LTTNG_OK;
905 goto error;
906 }
907 break;
908 case LTTNG_DST_PATH:
909 if (*uri->dst.path != '/' || strstr(uri->dst.path, "../")) {
910 ret_code = LTTNG_ERR_INVALID;
911 goto error;
912 }
913 DBG2("Setting trace directory path from URI to %s",
914 uri->dst.path);
915 memset(&consumer->dst, 0, sizeof(consumer->dst));
916
917 ret = lttng_strncpy(consumer->dst.session_root_path,
918 uri->dst.path,
919 sizeof(consumer->dst.session_root_path));
920 if (ret) {
921 ret_code = LTTNG_ERR_FATAL;
922 goto error;
923 }
924 consumer->type = CONSUMER_DST_LOCAL;
925 break;
926 }
927
928 ret_code = LTTNG_OK;
929 error:
930 return ret_code;
931 }
932
933 /*
934 * Init tracing by creating trace directory and sending fds kernel consumer.
935 */
936 static int init_kernel_tracing(struct ltt_kernel_session *session)
937 {
938 int ret = 0;
939 struct lttng_ht_iter iter;
940 struct consumer_socket *socket;
941
942 assert(session);
943
944 rcu_read_lock();
945
946 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
947 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
948 socket, node.node) {
949 pthread_mutex_lock(socket->lock);
950 ret = kernel_consumer_send_session(socket, session);
951 pthread_mutex_unlock(socket->lock);
952 if (ret < 0) {
953 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
954 goto error;
955 }
956 }
957 }
958
959 error:
960 rcu_read_unlock();
961 return ret;
962 }
963
964 /*
965 * Create a socket to the relayd using the URI.
966 *
967 * On success, the relayd_sock pointer is set to the created socket.
968 * Else, it remains untouched and an LTTng error code is returned.
969 */
970 static enum lttng_error_code create_connect_relayd(struct lttng_uri *uri,
971 struct lttcomm_relayd_sock **relayd_sock,
972 struct consumer_output *consumer)
973 {
974 int ret;
975 enum lttng_error_code status = LTTNG_OK;
976 struct lttcomm_relayd_sock *rsock;
977
978 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
979 RELAYD_VERSION_COMM_MINOR);
980 if (!rsock) {
981 status = LTTNG_ERR_FATAL;
982 goto error;
983 }
984
985 /*
986 * Connect to relayd so we can proceed with a session creation. This call
987 * can possibly block for an arbitrary amount of time to set the health
988 * state to be in poll execution.
989 */
990 health_poll_entry();
991 ret = relayd_connect(rsock);
992 health_poll_exit();
993 if (ret < 0) {
994 ERR("Unable to reach lttng-relayd");
995 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
996 goto free_sock;
997 }
998
999 /* Create socket for control stream. */
1000 if (uri->stype == LTTNG_STREAM_CONTROL) {
1001 uint64_t result_flags;
1002
1003 DBG3("Creating relayd stream socket from URI");
1004
1005 /* Check relayd version */
1006 ret = relayd_version_check(rsock);
1007 if (ret == LTTNG_ERR_RELAYD_VERSION_FAIL) {
1008 status = LTTNG_ERR_RELAYD_VERSION_FAIL;
1009 goto close_sock;
1010 } else if (ret < 0) {
1011 ERR("Unable to reach lttng-relayd");
1012 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
1013 goto close_sock;
1014 }
1015 consumer->relay_major_version = rsock->major;
1016 consumer->relay_minor_version = rsock->minor;
1017 ret = relayd_get_configuration(rsock, 0,
1018 &result_flags);
1019 if (ret < 0) {
1020 ERR("Unable to get relayd configuration");
1021 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
1022 goto close_sock;
1023 }
1024 if (result_flags & LTTCOMM_RELAYD_CONFIGURATION_FLAG_CLEAR_ALLOWED) {
1025 consumer->relay_allows_clear = true;
1026 }
1027 } else if (uri->stype == LTTNG_STREAM_DATA) {
1028 DBG3("Creating relayd data socket from URI");
1029 } else {
1030 /* Command is not valid */
1031 ERR("Relayd invalid stream type: %d", uri->stype);
1032 status = LTTNG_ERR_INVALID;
1033 goto close_sock;
1034 }
1035
1036 *relayd_sock = rsock;
1037
1038 return status;
1039
1040 close_sock:
1041 /* The returned value is not useful since we are on an error path. */
1042 (void) relayd_close(rsock);
1043 free_sock:
1044 free(rsock);
1045 error:
1046 return status;
1047 }
1048
1049 /*
1050 * Connect to the relayd using URI and send the socket to the right consumer.
1051 *
1052 * The consumer socket lock must be held by the caller.
1053 *
1054 * Returns LTTNG_OK on success or an LTTng error code on failure.
1055 */
1056 static enum lttng_error_code send_consumer_relayd_socket(
1057 unsigned int session_id,
1058 struct lttng_uri *relayd_uri,
1059 struct consumer_output *consumer,
1060 struct consumer_socket *consumer_sock,
1061 const char *session_name, const char *hostname,
1062 const char *base_path, int session_live_timer,
1063 const uint64_t *current_chunk_id,
1064 time_t session_creation_time,
1065 bool session_name_contains_creation_time)
1066 {
1067 int ret;
1068 struct lttcomm_relayd_sock *rsock = NULL;
1069 enum lttng_error_code status;
1070
1071 /* Connect to relayd and make version check if uri is the control. */
1072 status = create_connect_relayd(relayd_uri, &rsock, consumer);
1073 if (status != LTTNG_OK) {
1074 goto relayd_comm_error;
1075 }
1076 assert(rsock);
1077
1078 /* Set the network sequence index if not set. */
1079 if (consumer->net_seq_index == (uint64_t) -1ULL) {
1080 pthread_mutex_lock(&relayd_net_seq_idx_lock);
1081 /*
1082 * Increment net_seq_idx because we are about to transfer the
1083 * new relayd socket to the consumer.
1084 * Assign unique key so the consumer can match streams.
1085 */
1086 consumer->net_seq_index = ++relayd_net_seq_idx;
1087 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
1088 }
1089
1090 /* Send relayd socket to consumer. */
1091 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
1092 relayd_uri->stype, session_id,
1093 session_name, hostname, base_path,
1094 session_live_timer, current_chunk_id,
1095 session_creation_time, session_name_contains_creation_time);
1096 if (ret < 0) {
1097 status = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
1098 goto close_sock;
1099 }
1100
1101 /* Flag that the corresponding socket was sent. */
1102 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
1103 consumer_sock->control_sock_sent = 1;
1104 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
1105 consumer_sock->data_sock_sent = 1;
1106 }
1107
1108 /*
1109 * Close socket which was dup on the consumer side. The session daemon does
1110 * NOT keep track of the relayd socket(s) once transfer to the consumer.
1111 */
1112
1113 close_sock:
1114 if (status != LTTNG_OK) {
1115 /*
1116 * The consumer output for this session should not be used anymore
1117 * since the relayd connection failed thus making any tracing or/and
1118 * streaming not usable.
1119 */
1120 consumer->enabled = 0;
1121 }
1122 (void) relayd_close(rsock);
1123 free(rsock);
1124
1125 relayd_comm_error:
1126 return status;
1127 }
1128
1129 /*
1130 * Send both relayd sockets to a specific consumer and domain. This is a
1131 * helper function to facilitate sending the information to the consumer for a
1132 * session.
1133 *
1134 * The consumer socket lock must be held by the caller.
1135 *
1136 * Returns LTTNG_OK, or an LTTng error code on failure.
1137 */
1138 static enum lttng_error_code send_consumer_relayd_sockets(
1139 enum lttng_domain_type domain,
1140 unsigned int session_id, struct consumer_output *consumer,
1141 struct consumer_socket *sock, const char *session_name,
1142 const char *hostname, const char *base_path, int session_live_timer,
1143 const uint64_t *current_chunk_id, time_t session_creation_time,
1144 bool session_name_contains_creation_time)
1145 {
1146 enum lttng_error_code status = LTTNG_OK;
1147
1148 assert(consumer);
1149 assert(sock);
1150
1151 /* Sending control relayd socket. */
1152 if (!sock->control_sock_sent) {
1153 status = send_consumer_relayd_socket(session_id,
1154 &consumer->dst.net.control, consumer, sock,
1155 session_name, hostname, base_path, session_live_timer,
1156 current_chunk_id, session_creation_time,
1157 session_name_contains_creation_time);
1158 if (status != LTTNG_OK) {
1159 goto error;
1160 }
1161 }
1162
1163 /* Sending data relayd socket. */
1164 if (!sock->data_sock_sent) {
1165 status = send_consumer_relayd_socket(session_id,
1166 &consumer->dst.net.data, consumer, sock,
1167 session_name, hostname, base_path, session_live_timer,
1168 current_chunk_id, session_creation_time,
1169 session_name_contains_creation_time);
1170 if (status != LTTNG_OK) {
1171 goto error;
1172 }
1173 }
1174
1175 error:
1176 return status;
1177 }
1178
1179 /*
1180 * Setup relayd connections for a tracing session. First creates the socket to
1181 * the relayd and send them to the right domain consumer. Consumer type MUST be
1182 * network.
1183 */
1184 int cmd_setup_relayd(struct ltt_session *session)
1185 {
1186 int ret = LTTNG_OK;
1187 struct ltt_ust_session *usess;
1188 struct ltt_kernel_session *ksess;
1189 struct consumer_socket *socket;
1190 struct lttng_ht_iter iter;
1191 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
1192
1193 assert(session);
1194
1195 usess = session->ust_session;
1196 ksess = session->kernel_session;
1197
1198 DBG("Setting relayd for session %s", session->name);
1199
1200 rcu_read_lock();
1201 if (session->current_trace_chunk) {
1202 enum lttng_trace_chunk_status status = lttng_trace_chunk_get_id(
1203 session->current_trace_chunk, &current_chunk_id.value);
1204
1205 if (status == LTTNG_TRACE_CHUNK_STATUS_OK) {
1206 current_chunk_id.is_set = true;
1207 } else {
1208 ERR("Failed to get current trace chunk id");
1209 ret = LTTNG_ERR_UNK;
1210 goto error;
1211 }
1212 }
1213
1214 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1215 && usess->consumer->enabled) {
1216 /* For each consumer socket, send relayd sockets */
1217 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1218 socket, node.node) {
1219 pthread_mutex_lock(socket->lock);
1220 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1221 usess->consumer, socket,
1222 session->name, session->hostname,
1223 session->base_path,
1224 session->live_timer,
1225 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1226 session->creation_time,
1227 session->name_contains_creation_time);
1228 pthread_mutex_unlock(socket->lock);
1229 if (ret != LTTNG_OK) {
1230 goto error;
1231 }
1232 /* Session is now ready for network streaming. */
1233 session->net_handle = 1;
1234 }
1235 session->consumer->relay_major_version =
1236 usess->consumer->relay_major_version;
1237 session->consumer->relay_minor_version =
1238 usess->consumer->relay_minor_version;
1239 session->consumer->relay_allows_clear =
1240 usess->consumer->relay_allows_clear;
1241 }
1242
1243 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1244 && ksess->consumer->enabled) {
1245 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1246 socket, node.node) {
1247 pthread_mutex_lock(socket->lock);
1248 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1249 ksess->consumer, socket,
1250 session->name, session->hostname,
1251 session->base_path,
1252 session->live_timer,
1253 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1254 session->creation_time,
1255 session->name_contains_creation_time);
1256 pthread_mutex_unlock(socket->lock);
1257 if (ret != LTTNG_OK) {
1258 goto error;
1259 }
1260 /* Session is now ready for network streaming. */
1261 session->net_handle = 1;
1262 }
1263 session->consumer->relay_major_version =
1264 ksess->consumer->relay_major_version;
1265 session->consumer->relay_minor_version =
1266 ksess->consumer->relay_minor_version;
1267 session->consumer->relay_allows_clear =
1268 ksess->consumer->relay_allows_clear;
1269 }
1270
1271 error:
1272 rcu_read_unlock();
1273 return ret;
1274 }
1275
1276 /*
1277 * Start a kernel session by opening all necessary streams.
1278 */
1279 int start_kernel_session(struct ltt_kernel_session *ksess)
1280 {
1281 int ret;
1282 struct ltt_kernel_channel *kchan;
1283
1284 /* Open kernel metadata */
1285 if (ksess->metadata == NULL && ksess->output_traces) {
1286 ret = kernel_open_metadata(ksess);
1287 if (ret < 0) {
1288 ret = LTTNG_ERR_KERN_META_FAIL;
1289 goto error;
1290 }
1291 }
1292
1293 /* Open kernel metadata stream */
1294 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1295 ret = kernel_open_metadata_stream(ksess);
1296 if (ret < 0) {
1297 ERR("Kernel create metadata stream failed");
1298 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1299 goto error;
1300 }
1301 }
1302
1303 /* For each channel */
1304 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1305 if (kchan->stream_count == 0) {
1306 ret = kernel_open_channel_stream(kchan);
1307 if (ret < 0) {
1308 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1309 goto error;
1310 }
1311 /* Update the stream global counter */
1312 ksess->stream_count_global += ret;
1313 }
1314 }
1315
1316 /* Setup kernel consumer socket and send fds to it */
1317 ret = init_kernel_tracing(ksess);
1318 if (ret != 0) {
1319 ret = LTTNG_ERR_KERN_START_FAIL;
1320 goto error;
1321 }
1322
1323 /* This start the kernel tracing */
1324 ret = kernel_start_session(ksess);
1325 if (ret < 0) {
1326 ret = LTTNG_ERR_KERN_START_FAIL;
1327 goto error;
1328 }
1329
1330 /* Quiescent wait after starting trace */
1331 kernel_wait_quiescent();
1332
1333 ksess->active = 1;
1334
1335 ret = LTTNG_OK;
1336
1337 error:
1338 return ret;
1339 }
1340
1341 int stop_kernel_session(struct ltt_kernel_session *ksess)
1342 {
1343 struct ltt_kernel_channel *kchan;
1344 bool error_occurred = false;
1345 int ret;
1346
1347 if (!ksess || !ksess->active) {
1348 return LTTNG_OK;
1349 }
1350 DBG("Stopping kernel tracing");
1351
1352 ret = kernel_stop_session(ksess);
1353 if (ret < 0) {
1354 ret = LTTNG_ERR_KERN_STOP_FAIL;
1355 goto error;
1356 }
1357
1358 kernel_wait_quiescent();
1359
1360 /* Flush metadata after stopping (if exists) */
1361 if (ksess->metadata_stream_fd >= 0) {
1362 ret = kernel_metadata_flush_buffer(ksess->metadata_stream_fd);
1363 if (ret < 0) {
1364 ERR("Kernel metadata flush failed");
1365 error_occurred = true;
1366 }
1367 }
1368
1369 /* Flush all buffers after stopping */
1370 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1371 ret = kernel_flush_buffer(kchan);
1372 if (ret < 0) {
1373 ERR("Kernel flush buffer error");
1374 error_occurred = true;
1375 }
1376 }
1377
1378 ksess->active = 0;
1379 if (error_occurred) {
1380 ret = LTTNG_ERR_UNK;
1381 } else {
1382 ret = LTTNG_OK;
1383 }
1384 error:
1385 return ret;
1386 }
1387
1388 /*
1389 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1390 */
1391 int cmd_disable_channel(struct ltt_session *session,
1392 enum lttng_domain_type domain, char *channel_name)
1393 {
1394 int ret;
1395 struct ltt_ust_session *usess;
1396
1397 usess = session->ust_session;
1398
1399 rcu_read_lock();
1400
1401 switch (domain) {
1402 case LTTNG_DOMAIN_KERNEL:
1403 {
1404 ret = channel_kernel_disable(session->kernel_session,
1405 channel_name);
1406 if (ret != LTTNG_OK) {
1407 goto error;
1408 }
1409
1410 kernel_wait_quiescent();
1411 break;
1412 }
1413 case LTTNG_DOMAIN_UST:
1414 {
1415 struct ltt_ust_channel *uchan;
1416 struct lttng_ht *chan_ht;
1417
1418 chan_ht = usess->domain_global.channels;
1419
1420 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1421 if (uchan == NULL) {
1422 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1423 goto error;
1424 }
1425
1426 ret = channel_ust_disable(usess, uchan);
1427 if (ret != LTTNG_OK) {
1428 goto error;
1429 }
1430 break;
1431 }
1432 default:
1433 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1434 goto error;
1435 }
1436
1437 ret = LTTNG_OK;
1438
1439 error:
1440 rcu_read_unlock();
1441 return ret;
1442 }
1443
1444 /*
1445 * Command LTTNG_TRACK_PID processed by the client thread.
1446 *
1447 * Called with session lock held.
1448 */
1449 int cmd_track_pid(struct ltt_session *session, enum lttng_domain_type domain,
1450 int pid)
1451 {
1452 int ret;
1453
1454 rcu_read_lock();
1455
1456 switch (domain) {
1457 case LTTNG_DOMAIN_KERNEL:
1458 {
1459 struct ltt_kernel_session *ksess;
1460
1461 ksess = session->kernel_session;
1462
1463 ret = kernel_track_pid(ksess, pid);
1464 if (ret != LTTNG_OK) {
1465 goto error;
1466 }
1467
1468 kernel_wait_quiescent();
1469 break;
1470 }
1471 case LTTNG_DOMAIN_UST:
1472 {
1473 struct ltt_ust_session *usess;
1474
1475 usess = session->ust_session;
1476
1477 ret = trace_ust_track_pid(usess, pid);
1478 if (ret != LTTNG_OK) {
1479 goto error;
1480 }
1481 break;
1482 }
1483 default:
1484 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1485 goto error;
1486 }
1487
1488 ret = LTTNG_OK;
1489
1490 error:
1491 rcu_read_unlock();
1492 return ret;
1493 }
1494
1495 /*
1496 * Command LTTNG_UNTRACK_PID processed by the client thread.
1497 *
1498 * Called with session lock held.
1499 */
1500 int cmd_untrack_pid(struct ltt_session *session, enum lttng_domain_type domain,
1501 int pid)
1502 {
1503 int ret;
1504
1505 rcu_read_lock();
1506
1507 switch (domain) {
1508 case LTTNG_DOMAIN_KERNEL:
1509 {
1510 struct ltt_kernel_session *ksess;
1511
1512 ksess = session->kernel_session;
1513
1514 ret = kernel_untrack_pid(ksess, pid);
1515 if (ret != LTTNG_OK) {
1516 goto error;
1517 }
1518
1519 kernel_wait_quiescent();
1520 break;
1521 }
1522 case LTTNG_DOMAIN_UST:
1523 {
1524 struct ltt_ust_session *usess;
1525
1526 usess = session->ust_session;
1527
1528 ret = trace_ust_untrack_pid(usess, pid);
1529 if (ret != LTTNG_OK) {
1530 goto error;
1531 }
1532 break;
1533 }
1534 default:
1535 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1536 goto error;
1537 }
1538
1539 ret = LTTNG_OK;
1540
1541 error:
1542 rcu_read_unlock();
1543 return ret;
1544 }
1545
1546 /*
1547 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1548 *
1549 * The wpipe arguments is used as a notifier for the kernel thread.
1550 */
1551 int cmd_enable_channel(struct ltt_session *session,
1552 const struct lttng_domain *domain, const struct lttng_channel *_attr, int wpipe)
1553 {
1554 int ret;
1555 struct ltt_ust_session *usess = session->ust_session;
1556 struct lttng_ht *chan_ht;
1557 size_t len;
1558 struct lttng_channel attr;
1559
1560 assert(session);
1561 assert(_attr);
1562 assert(domain);
1563
1564 attr = *_attr;
1565 len = lttng_strnlen(attr.name, sizeof(attr.name));
1566
1567 /* Validate channel name */
1568 if (attr.name[0] == '.' ||
1569 memchr(attr.name, '/', len) != NULL) {
1570 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1571 goto end;
1572 }
1573
1574 DBG("Enabling channel %s for session %s", attr.name, session->name);
1575
1576 rcu_read_lock();
1577
1578 /*
1579 * Don't try to enable a channel if the session has been started at
1580 * some point in time before. The tracer does not allow it.
1581 */
1582 if (session->has_been_started) {
1583 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1584 goto error;
1585 }
1586
1587 /*
1588 * If the session is a live session, remove the switch timer, the
1589 * live timer does the same thing but sends also synchronisation
1590 * beacons for inactive streams.
1591 */
1592 if (session->live_timer > 0) {
1593 attr.attr.live_timer_interval = session->live_timer;
1594 attr.attr.switch_timer_interval = 0;
1595 }
1596
1597 /* Check for feature support */
1598 switch (domain->type) {
1599 case LTTNG_DOMAIN_KERNEL:
1600 {
1601 if (kernel_supports_ring_buffer_snapshot_sample_positions() != 1) {
1602 /* Sampling position of buffer is not supported */
1603 WARN("Kernel tracer does not support buffer monitoring. "
1604 "Setting the monitor interval timer to 0 "
1605 "(disabled) for channel '%s' of session '%s'",
1606 attr.name, session->name);
1607 lttng_channel_set_monitor_timer_interval(&attr, 0);
1608 }
1609 break;
1610 }
1611 case LTTNG_DOMAIN_UST:
1612 break;
1613 case LTTNG_DOMAIN_JUL:
1614 case LTTNG_DOMAIN_LOG4J:
1615 case LTTNG_DOMAIN_PYTHON:
1616 if (!agent_tracing_is_enabled()) {
1617 DBG("Attempted to enable a channel in an agent domain but the agent thread is not running");
1618 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
1619 goto error;
1620 }
1621 break;
1622 default:
1623 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1624 goto error;
1625 }
1626
1627 switch (domain->type) {
1628 case LTTNG_DOMAIN_KERNEL:
1629 {
1630 struct ltt_kernel_channel *kchan;
1631
1632 kchan = trace_kernel_get_channel_by_name(attr.name,
1633 session->kernel_session);
1634 if (kchan == NULL) {
1635 if (session->snapshot.nb_output > 0 ||
1636 session->snapshot_mode) {
1637 /* Enforce mmap output for snapshot sessions. */
1638 attr.attr.output = LTTNG_EVENT_MMAP;
1639 }
1640 ret = channel_kernel_create(session->kernel_session, &attr, wpipe);
1641 if (attr.name[0] != '\0') {
1642 session->kernel_session->has_non_default_channel = 1;
1643 }
1644 } else {
1645 ret = channel_kernel_enable(session->kernel_session, kchan);
1646 }
1647
1648 if (ret != LTTNG_OK) {
1649 goto error;
1650 }
1651
1652 kernel_wait_quiescent();
1653 break;
1654 }
1655 case LTTNG_DOMAIN_UST:
1656 case LTTNG_DOMAIN_JUL:
1657 case LTTNG_DOMAIN_LOG4J:
1658 case LTTNG_DOMAIN_PYTHON:
1659 {
1660 struct ltt_ust_channel *uchan;
1661
1662 /*
1663 * FIXME
1664 *
1665 * Current agent implementation limitations force us to allow
1666 * only one channel at once in "agent" subdomains. Each
1667 * subdomain has a default channel name which must be strictly
1668 * adhered to.
1669 */
1670 if (domain->type == LTTNG_DOMAIN_JUL) {
1671 if (strncmp(attr.name, DEFAULT_JUL_CHANNEL_NAME,
1672 LTTNG_SYMBOL_NAME_LEN)) {
1673 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1674 goto error;
1675 }
1676 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1677 if (strncmp(attr.name, DEFAULT_LOG4J_CHANNEL_NAME,
1678 LTTNG_SYMBOL_NAME_LEN)) {
1679 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1680 goto error;
1681 }
1682 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1683 if (strncmp(attr.name, DEFAULT_PYTHON_CHANNEL_NAME,
1684 LTTNG_SYMBOL_NAME_LEN)) {
1685 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1686 goto error;
1687 }
1688 }
1689
1690 chan_ht = usess->domain_global.channels;
1691
1692 uchan = trace_ust_find_channel_by_name(chan_ht, attr.name);
1693 if (uchan == NULL) {
1694 ret = channel_ust_create(usess, &attr, domain->buf_type);
1695 if (attr.name[0] != '\0') {
1696 usess->has_non_default_channel = 1;
1697 }
1698 } else {
1699 ret = channel_ust_enable(usess, uchan);
1700 }
1701 break;
1702 }
1703 default:
1704 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1705 goto error;
1706 }
1707
1708 if (ret == LTTNG_OK && attr.attr.output != LTTNG_EVENT_MMAP) {
1709 session->has_non_mmap_channel = true;
1710 }
1711 error:
1712 rcu_read_unlock();
1713 end:
1714 return ret;
1715 }
1716
1717 /*
1718 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1719 */
1720 int cmd_disable_event(struct ltt_session *session,
1721 enum lttng_domain_type domain, const char *channel_name,
1722 const struct lttng_event *event)
1723 {
1724 int ret;
1725 const char *event_name;
1726
1727 DBG("Disable event command for event \'%s\'", event->name);
1728
1729 event_name = event->name;
1730
1731 /* Error out on unhandled search criteria */
1732 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1733 || event->pid || event->filter || event->exclusion) {
1734 ret = LTTNG_ERR_UNK;
1735 goto error;
1736 }
1737
1738 rcu_read_lock();
1739
1740 switch (domain) {
1741 case LTTNG_DOMAIN_KERNEL:
1742 {
1743 struct ltt_kernel_channel *kchan;
1744 struct ltt_kernel_session *ksess;
1745
1746 ksess = session->kernel_session;
1747
1748 /*
1749 * If a non-default channel has been created in the
1750 * session, explicitely require that -c chan_name needs
1751 * to be provided.
1752 */
1753 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1754 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1755 goto error_unlock;
1756 }
1757
1758 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1759 if (kchan == NULL) {
1760 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1761 goto error_unlock;
1762 }
1763
1764 switch (event->type) {
1765 case LTTNG_EVENT_ALL:
1766 case LTTNG_EVENT_TRACEPOINT:
1767 case LTTNG_EVENT_SYSCALL:
1768 case LTTNG_EVENT_PROBE:
1769 case LTTNG_EVENT_FUNCTION:
1770 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1771 if (event_name[0] == '\0') {
1772 ret = event_kernel_disable_event(kchan,
1773 NULL, event->type);
1774 } else {
1775 ret = event_kernel_disable_event(kchan,
1776 event_name, event->type);
1777 }
1778 if (ret != LTTNG_OK) {
1779 goto error_unlock;
1780 }
1781 break;
1782 default:
1783 ret = LTTNG_ERR_UNK;
1784 goto error_unlock;
1785 }
1786
1787 kernel_wait_quiescent();
1788 break;
1789 }
1790 case LTTNG_DOMAIN_UST:
1791 {
1792 struct ltt_ust_channel *uchan;
1793 struct ltt_ust_session *usess;
1794
1795 usess = session->ust_session;
1796
1797 if (validate_ust_event_name(event_name)) {
1798 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1799 goto error_unlock;
1800 }
1801
1802 /*
1803 * If a non-default channel has been created in the
1804 * session, explicitly require that -c chan_name needs
1805 * to be provided.
1806 */
1807 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1808 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1809 goto error_unlock;
1810 }
1811
1812 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1813 channel_name);
1814 if (uchan == NULL) {
1815 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1816 goto error_unlock;
1817 }
1818
1819 switch (event->type) {
1820 case LTTNG_EVENT_ALL:
1821 /*
1822 * An empty event name means that everything
1823 * should be disabled.
1824 */
1825 if (event->name[0] == '\0') {
1826 ret = event_ust_disable_all_tracepoints(usess, uchan);
1827 } else {
1828 ret = event_ust_disable_tracepoint(usess, uchan,
1829 event_name);
1830 }
1831 if (ret != LTTNG_OK) {
1832 goto error_unlock;
1833 }
1834 break;
1835 default:
1836 ret = LTTNG_ERR_UNK;
1837 goto error_unlock;
1838 }
1839
1840 DBG3("Disable UST event %s in channel %s completed", event_name,
1841 channel_name);
1842 break;
1843 }
1844 case LTTNG_DOMAIN_LOG4J:
1845 case LTTNG_DOMAIN_JUL:
1846 case LTTNG_DOMAIN_PYTHON:
1847 {
1848 struct agent *agt;
1849 struct ltt_ust_session *usess = session->ust_session;
1850
1851 assert(usess);
1852
1853 switch (event->type) {
1854 case LTTNG_EVENT_ALL:
1855 break;
1856 default:
1857 ret = LTTNG_ERR_UNK;
1858 goto error_unlock;
1859 }
1860
1861 agt = trace_ust_find_agent(usess, domain);
1862 if (!agt) {
1863 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1864 goto error_unlock;
1865 }
1866 /*
1867 * An empty event name means that everything
1868 * should be disabled.
1869 */
1870 if (event->name[0] == '\0') {
1871 ret = event_agent_disable_all(usess, agt);
1872 } else {
1873 ret = event_agent_disable(usess, agt, event_name);
1874 }
1875 if (ret != LTTNG_OK) {
1876 goto error_unlock;
1877 }
1878
1879 break;
1880 }
1881 default:
1882 ret = LTTNG_ERR_UND;
1883 goto error_unlock;
1884 }
1885
1886 ret = LTTNG_OK;
1887
1888 error_unlock:
1889 rcu_read_unlock();
1890 error:
1891 return ret;
1892 }
1893
1894 /*
1895 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1896 */
1897 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1898 char *channel_name, const struct lttng_event_context *ctx, int kwpipe)
1899 {
1900 int ret, chan_kern_created = 0, chan_ust_created = 0;
1901 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1902
1903 /*
1904 * Don't try to add a context if the session has been started at
1905 * some point in time before. The tracer does not allow it and would
1906 * result in a corrupted trace.
1907 */
1908 if (session->has_been_started) {
1909 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1910 goto end;
1911 }
1912
1913 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1914 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1915 app_ctx_name = ctx->u.app_ctx.ctx_name;
1916 }
1917
1918 switch (domain) {
1919 case LTTNG_DOMAIN_KERNEL:
1920 assert(session->kernel_session);
1921
1922 if (session->kernel_session->channel_count == 0) {
1923 /* Create default channel */
1924 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1925 if (ret != LTTNG_OK) {
1926 goto error;
1927 }
1928 chan_kern_created = 1;
1929 }
1930 /* Add kernel context to kernel tracer */
1931 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1932 if (ret != LTTNG_OK) {
1933 goto error;
1934 }
1935 break;
1936 case LTTNG_DOMAIN_JUL:
1937 case LTTNG_DOMAIN_LOG4J:
1938 {
1939 /*
1940 * Validate channel name.
1941 * If no channel name is given and the domain is JUL or LOG4J,
1942 * set it to the appropriate domain-specific channel name. If
1943 * a name is provided but does not match the expexted channel
1944 * name, return an error.
1945 */
1946 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1947 strcmp(channel_name,
1948 DEFAULT_JUL_CHANNEL_NAME)) {
1949 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1950 goto error;
1951 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1952 strcmp(channel_name,
1953 DEFAULT_LOG4J_CHANNEL_NAME)) {
1954 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1955 goto error;
1956 }
1957 /* break is _not_ missing here. */
1958 }
1959 case LTTNG_DOMAIN_UST:
1960 {
1961 struct ltt_ust_session *usess = session->ust_session;
1962 unsigned int chan_count;
1963
1964 assert(usess);
1965
1966 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1967 if (chan_count == 0) {
1968 struct lttng_channel *attr;
1969 /* Create default channel */
1970 attr = channel_new_default_attr(domain, usess->buffer_type);
1971 if (attr == NULL) {
1972 ret = LTTNG_ERR_FATAL;
1973 goto error;
1974 }
1975
1976 ret = channel_ust_create(usess, attr, usess->buffer_type);
1977 if (ret != LTTNG_OK) {
1978 free(attr);
1979 goto error;
1980 }
1981 channel_attr_destroy(attr);
1982 chan_ust_created = 1;
1983 }
1984
1985 ret = context_ust_add(usess, domain, ctx, channel_name);
1986 free(app_ctx_provider_name);
1987 free(app_ctx_name);
1988 app_ctx_name = NULL;
1989 app_ctx_provider_name = NULL;
1990 if (ret != LTTNG_OK) {
1991 goto error;
1992 }
1993 break;
1994 }
1995 default:
1996 ret = LTTNG_ERR_UND;
1997 goto error;
1998 }
1999
2000 ret = LTTNG_OK;
2001 goto end;
2002
2003 error:
2004 if (chan_kern_created) {
2005 struct ltt_kernel_channel *kchan =
2006 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
2007 session->kernel_session);
2008 /* Created previously, this should NOT fail. */
2009 assert(kchan);
2010 kernel_destroy_channel(kchan);
2011 }
2012
2013 if (chan_ust_created) {
2014 struct ltt_ust_channel *uchan =
2015 trace_ust_find_channel_by_name(
2016 session->ust_session->domain_global.channels,
2017 DEFAULT_CHANNEL_NAME);
2018 /* Created previously, this should NOT fail. */
2019 assert(uchan);
2020 /* Remove from the channel list of the session. */
2021 trace_ust_delete_channel(session->ust_session->domain_global.channels,
2022 uchan);
2023 trace_ust_destroy_channel(uchan);
2024 }
2025 end:
2026 free(app_ctx_provider_name);
2027 free(app_ctx_name);
2028 return ret;
2029 }
2030
2031 static inline bool name_starts_with(const char *name, const char *prefix)
2032 {
2033 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
2034
2035 return !strncmp(name, prefix, max_cmp_len);
2036 }
2037
2038 /* Perform userspace-specific event name validation */
2039 static int validate_ust_event_name(const char *name)
2040 {
2041 int ret = 0;
2042
2043 if (!name) {
2044 ret = -1;
2045 goto end;
2046 }
2047
2048 /*
2049 * Check name against all internal UST event component namespaces used
2050 * by the agents.
2051 */
2052 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
2053 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
2054 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
2055 ret = -1;
2056 }
2057
2058 end:
2059 return ret;
2060 }
2061
2062 /*
2063 * Internal version of cmd_enable_event() with a supplemental
2064 * "internal_event" flag which is used to enable internal events which should
2065 * be hidden from clients. Such events are used in the agent implementation to
2066 * enable the events through which all "agent" events are funeled.
2067 */
2068 static int _cmd_enable_event(struct ltt_session *session,
2069 const struct lttng_domain *domain,
2070 char *channel_name, struct lttng_event *event,
2071 char *filter_expression,
2072 struct lttng_filter_bytecode *filter,
2073 struct lttng_event_exclusion *exclusion,
2074 int wpipe, bool internal_event)
2075 {
2076 int ret = 0, channel_created = 0;
2077 struct lttng_channel *attr = NULL;
2078
2079 assert(session);
2080 assert(event);
2081 assert(channel_name);
2082
2083 /* If we have a filter, we must have its filter expression */
2084 assert(!(!!filter_expression ^ !!filter));
2085
2086 /* Normalize event name as a globbing pattern */
2087 strutils_normalize_star_glob_pattern(event->name);
2088
2089 /* Normalize exclusion names as globbing patterns */
2090 if (exclusion) {
2091 size_t i;
2092
2093 for (i = 0; i < exclusion->count; i++) {
2094 char *name = LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
2095
2096 strutils_normalize_star_glob_pattern(name);
2097 }
2098 }
2099
2100 DBG("Enable event command for event \'%s\'", event->name);
2101
2102 rcu_read_lock();
2103
2104 switch (domain->type) {
2105 case LTTNG_DOMAIN_KERNEL:
2106 {
2107 struct ltt_kernel_channel *kchan;
2108
2109 /*
2110 * If a non-default channel has been created in the
2111 * session, explicitely require that -c chan_name needs
2112 * to be provided.
2113 */
2114 if (session->kernel_session->has_non_default_channel
2115 && channel_name[0] == '\0') {
2116 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2117 goto error;
2118 }
2119
2120 kchan = trace_kernel_get_channel_by_name(channel_name,
2121 session->kernel_session);
2122 if (kchan == NULL) {
2123 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
2124 LTTNG_BUFFER_GLOBAL);
2125 if (attr == NULL) {
2126 ret = LTTNG_ERR_FATAL;
2127 goto error;
2128 }
2129 if (lttng_strncpy(attr->name, channel_name,
2130 sizeof(attr->name))) {
2131 ret = LTTNG_ERR_INVALID;
2132 goto error;
2133 }
2134
2135 ret = cmd_enable_channel(session, domain, attr, wpipe);
2136 if (ret != LTTNG_OK) {
2137 goto error;
2138 }
2139 channel_created = 1;
2140 }
2141
2142 /* Get the newly created kernel channel pointer */
2143 kchan = trace_kernel_get_channel_by_name(channel_name,
2144 session->kernel_session);
2145 if (kchan == NULL) {
2146 /* This sould not happen... */
2147 ret = LTTNG_ERR_FATAL;
2148 goto error;
2149 }
2150
2151 switch (event->type) {
2152 case LTTNG_EVENT_ALL:
2153 {
2154 char *filter_expression_a = NULL;
2155 struct lttng_filter_bytecode *filter_a = NULL;
2156
2157 /*
2158 * We need to duplicate filter_expression and filter,
2159 * because ownership is passed to first enable
2160 * event.
2161 */
2162 if (filter_expression) {
2163 filter_expression_a = strdup(filter_expression);
2164 if (!filter_expression_a) {
2165 ret = LTTNG_ERR_FATAL;
2166 goto error;
2167 }
2168 }
2169 if (filter) {
2170 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
2171 if (!filter_a) {
2172 free(filter_expression_a);
2173 ret = LTTNG_ERR_FATAL;
2174 goto error;
2175 }
2176 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
2177 }
2178 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
2179 ret = event_kernel_enable_event(kchan, event,
2180 filter_expression, filter);
2181 /* We have passed ownership */
2182 filter_expression = NULL;
2183 filter = NULL;
2184 if (ret != LTTNG_OK) {
2185 if (channel_created) {
2186 /* Let's not leak a useless channel. */
2187 kernel_destroy_channel(kchan);
2188 }
2189 free(filter_expression_a);
2190 free(filter_a);
2191 goto error;
2192 }
2193 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
2194 ret = event_kernel_enable_event(kchan, event,
2195 filter_expression_a, filter_a);
2196 /* We have passed ownership */
2197 filter_expression_a = NULL;
2198 filter_a = NULL;
2199 if (ret != LTTNG_OK) {
2200 goto error;
2201 }
2202 break;
2203 }
2204 case LTTNG_EVENT_PROBE:
2205 case LTTNG_EVENT_USERSPACE_PROBE:
2206 case LTTNG_EVENT_FUNCTION:
2207 case LTTNG_EVENT_FUNCTION_ENTRY:
2208 case LTTNG_EVENT_TRACEPOINT:
2209 ret = event_kernel_enable_event(kchan, event,
2210 filter_expression, filter);
2211 /* We have passed ownership */
2212 filter_expression = NULL;
2213 filter = NULL;
2214 if (ret != LTTNG_OK) {
2215 if (channel_created) {
2216 /* Let's not leak a useless channel. */
2217 kernel_destroy_channel(kchan);
2218 }
2219 goto error;
2220 }
2221 break;
2222 case LTTNG_EVENT_SYSCALL:
2223 ret = event_kernel_enable_event(kchan, event,
2224 filter_expression, filter);
2225 /* We have passed ownership */
2226 filter_expression = NULL;
2227 filter = NULL;
2228 if (ret != LTTNG_OK) {
2229 goto error;
2230 }
2231 break;
2232 default:
2233 ret = LTTNG_ERR_UNK;
2234 goto error;
2235 }
2236
2237 kernel_wait_quiescent();
2238 break;
2239 }
2240 case LTTNG_DOMAIN_UST:
2241 {
2242 struct ltt_ust_channel *uchan;
2243 struct ltt_ust_session *usess = session->ust_session;
2244
2245 assert(usess);
2246
2247 /*
2248 * If a non-default channel has been created in the
2249 * session, explicitely require that -c chan_name needs
2250 * to be provided.
2251 */
2252 if (usess->has_non_default_channel && channel_name[0] == '\0') {
2253 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2254 goto error;
2255 }
2256
2257 /* Get channel from global UST domain */
2258 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2259 channel_name);
2260 if (uchan == NULL) {
2261 /* Create default channel */
2262 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
2263 usess->buffer_type);
2264 if (attr == NULL) {
2265 ret = LTTNG_ERR_FATAL;
2266 goto error;
2267 }
2268 if (lttng_strncpy(attr->name, channel_name,
2269 sizeof(attr->name))) {
2270 ret = LTTNG_ERR_INVALID;
2271 goto error;
2272 }
2273
2274 ret = cmd_enable_channel(session, domain, attr, wpipe);
2275 if (ret != LTTNG_OK) {
2276 goto error;
2277 }
2278
2279 /* Get the newly created channel reference back */
2280 uchan = trace_ust_find_channel_by_name(
2281 usess->domain_global.channels, channel_name);
2282 assert(uchan);
2283 }
2284
2285 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2286 /*
2287 * Don't allow users to add UST events to channels which
2288 * are assigned to a userspace subdomain (JUL, Log4J,
2289 * Python, etc.).
2290 */
2291 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2292 goto error;
2293 }
2294
2295 if (!internal_event) {
2296 /*
2297 * Ensure the event name is not reserved for internal
2298 * use.
2299 */
2300 ret = validate_ust_event_name(event->name);
2301 if (ret) {
2302 WARN("Userspace event name %s failed validation.",
2303 event->name);
2304 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2305 goto error;
2306 }
2307 }
2308
2309 /* At this point, the session and channel exist on the tracer */
2310 ret = event_ust_enable_tracepoint(usess, uchan, event,
2311 filter_expression, filter, exclusion,
2312 internal_event);
2313 /* We have passed ownership */
2314 filter_expression = NULL;
2315 filter = NULL;
2316 exclusion = NULL;
2317 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2318 goto already_enabled;
2319 } else if (ret != LTTNG_OK) {
2320 goto error;
2321 }
2322 break;
2323 }
2324 case LTTNG_DOMAIN_LOG4J:
2325 case LTTNG_DOMAIN_JUL:
2326 case LTTNG_DOMAIN_PYTHON:
2327 {
2328 const char *default_event_name, *default_chan_name;
2329 struct agent *agt;
2330 struct lttng_event uevent;
2331 struct lttng_domain tmp_dom;
2332 struct ltt_ust_session *usess = session->ust_session;
2333
2334 assert(usess);
2335
2336 if (!agent_tracing_is_enabled()) {
2337 DBG("Attempted to enable an event in an agent domain but the agent thread is not running");
2338 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
2339 goto error;
2340 }
2341
2342 agt = trace_ust_find_agent(usess, domain->type);
2343 if (!agt) {
2344 agt = agent_create(domain->type);
2345 if (!agt) {
2346 ret = LTTNG_ERR_NOMEM;
2347 goto error;
2348 }
2349 agent_add(agt, usess->agents);
2350 }
2351
2352 /* Create the default tracepoint. */
2353 memset(&uevent, 0, sizeof(uevent));
2354 uevent.type = LTTNG_EVENT_TRACEPOINT;
2355 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2356 default_event_name = event_get_default_agent_ust_name(
2357 domain->type);
2358 if (!default_event_name) {
2359 ret = LTTNG_ERR_FATAL;
2360 goto error;
2361 }
2362 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2363 uevent.name[sizeof(uevent.name) - 1] = '\0';
2364
2365 /*
2366 * The domain type is changed because we are about to enable the
2367 * default channel and event for the JUL domain that are hardcoded.
2368 * This happens in the UST domain.
2369 */
2370 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2371 tmp_dom.type = LTTNG_DOMAIN_UST;
2372
2373 switch (domain->type) {
2374 case LTTNG_DOMAIN_LOG4J:
2375 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2376 break;
2377 case LTTNG_DOMAIN_JUL:
2378 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2379 break;
2380 case LTTNG_DOMAIN_PYTHON:
2381 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2382 break;
2383 default:
2384 /* The switch/case we are in makes this impossible */
2385 assert(0);
2386 }
2387
2388 {
2389 char *filter_expression_copy = NULL;
2390 struct lttng_filter_bytecode *filter_copy = NULL;
2391
2392 if (filter) {
2393 const size_t filter_size = sizeof(
2394 struct lttng_filter_bytecode)
2395 + filter->len;
2396
2397 filter_copy = zmalloc(filter_size);
2398 if (!filter_copy) {
2399 ret = LTTNG_ERR_NOMEM;
2400 goto error;
2401 }
2402 memcpy(filter_copy, filter, filter_size);
2403
2404 filter_expression_copy =
2405 strdup(filter_expression);
2406 if (!filter_expression) {
2407 ret = LTTNG_ERR_NOMEM;
2408 }
2409
2410 if (!filter_expression_copy || !filter_copy) {
2411 free(filter_expression_copy);
2412 free(filter_copy);
2413 goto error;
2414 }
2415 }
2416
2417 ret = cmd_enable_event_internal(session, &tmp_dom,
2418 (char *) default_chan_name,
2419 &uevent, filter_expression_copy,
2420 filter_copy, NULL, wpipe);
2421 }
2422
2423 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2424 goto already_enabled;
2425 } else if (ret != LTTNG_OK) {
2426 goto error;
2427 }
2428
2429 /* The wild card * means that everything should be enabled. */
2430 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2431 ret = event_agent_enable_all(usess, agt, event, filter,
2432 filter_expression);
2433 } else {
2434 ret = event_agent_enable(usess, agt, event, filter,
2435 filter_expression);
2436 }
2437 filter = NULL;
2438 filter_expression = NULL;
2439 if (ret != LTTNG_OK) {
2440 goto error;
2441 }
2442
2443 break;
2444 }
2445 default:
2446 ret = LTTNG_ERR_UND;
2447 goto error;
2448 }
2449
2450 ret = LTTNG_OK;
2451
2452 already_enabled:
2453 error:
2454 free(filter_expression);
2455 free(filter);
2456 free(exclusion);
2457 channel_attr_destroy(attr);
2458 rcu_read_unlock();
2459 return ret;
2460 }
2461
2462 /*
2463 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2464 * We own filter, exclusion, and filter_expression.
2465 */
2466 int cmd_enable_event(struct ltt_session *session,
2467 const struct lttng_domain *domain,
2468 char *channel_name, struct lttng_event *event,
2469 char *filter_expression,
2470 struct lttng_filter_bytecode *filter,
2471 struct lttng_event_exclusion *exclusion,
2472 int wpipe)
2473 {
2474 return _cmd_enable_event(session, domain, channel_name, event,
2475 filter_expression, filter, exclusion, wpipe, false);
2476 }
2477
2478 /*
2479 * Enable an event which is internal to LTTng. An internal should
2480 * never be made visible to clients and are immune to checks such as
2481 * reserved names.
2482 */
2483 static int cmd_enable_event_internal(struct ltt_session *session,
2484 const struct lttng_domain *domain,
2485 char *channel_name, struct lttng_event *event,
2486 char *filter_expression,
2487 struct lttng_filter_bytecode *filter,
2488 struct lttng_event_exclusion *exclusion,
2489 int wpipe)
2490 {
2491 return _cmd_enable_event(session, domain, channel_name, event,
2492 filter_expression, filter, exclusion, wpipe, true);
2493 }
2494
2495 /*
2496 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2497 */
2498 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2499 struct lttng_event **events)
2500 {
2501 int ret;
2502 ssize_t nb_events = 0;
2503
2504 switch (domain) {
2505 case LTTNG_DOMAIN_KERNEL:
2506 nb_events = kernel_list_events(events);
2507 if (nb_events < 0) {
2508 ret = LTTNG_ERR_KERN_LIST_FAIL;
2509 goto error;
2510 }
2511 break;
2512 case LTTNG_DOMAIN_UST:
2513 nb_events = ust_app_list_events(events);
2514 if (nb_events < 0) {
2515 ret = LTTNG_ERR_UST_LIST_FAIL;
2516 goto error;
2517 }
2518 break;
2519 case LTTNG_DOMAIN_LOG4J:
2520 case LTTNG_DOMAIN_JUL:
2521 case LTTNG_DOMAIN_PYTHON:
2522 nb_events = agent_list_events(events, domain);
2523 if (nb_events < 0) {
2524 ret = LTTNG_ERR_UST_LIST_FAIL;
2525 goto error;
2526 }
2527 break;
2528 default:
2529 ret = LTTNG_ERR_UND;
2530 goto error;
2531 }
2532
2533 return nb_events;
2534
2535 error:
2536 /* Return negative value to differentiate return code */
2537 return -ret;
2538 }
2539
2540 /*
2541 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2542 */
2543 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2544 struct lttng_event_field **fields)
2545 {
2546 int ret;
2547 ssize_t nb_fields = 0;
2548
2549 switch (domain) {
2550 case LTTNG_DOMAIN_UST:
2551 nb_fields = ust_app_list_event_fields(fields);
2552 if (nb_fields < 0) {
2553 ret = LTTNG_ERR_UST_LIST_FAIL;
2554 goto error;
2555 }
2556 break;
2557 case LTTNG_DOMAIN_KERNEL:
2558 default: /* fall-through */
2559 ret = LTTNG_ERR_UND;
2560 goto error;
2561 }
2562
2563 return nb_fields;
2564
2565 error:
2566 /* Return negative value to differentiate return code */
2567 return -ret;
2568 }
2569
2570 ssize_t cmd_list_syscalls(struct lttng_event **events)
2571 {
2572 return syscall_table_list(events);
2573 }
2574
2575 /*
2576 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
2577 *
2578 * Called with session lock held.
2579 */
2580 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
2581 enum lttng_domain_type domain, int32_t **pids)
2582 {
2583 int ret;
2584 ssize_t nr_pids = 0;
2585
2586 switch (domain) {
2587 case LTTNG_DOMAIN_KERNEL:
2588 {
2589 struct ltt_kernel_session *ksess;
2590
2591 ksess = session->kernel_session;
2592 nr_pids = kernel_list_tracker_pids(ksess, pids);
2593 if (nr_pids < 0) {
2594 ret = LTTNG_ERR_KERN_LIST_FAIL;
2595 goto error;
2596 }
2597 break;
2598 }
2599 case LTTNG_DOMAIN_UST:
2600 {
2601 struct ltt_ust_session *usess;
2602
2603 usess = session->ust_session;
2604 nr_pids = trace_ust_list_tracker_pids(usess, pids);
2605 if (nr_pids < 0) {
2606 ret = LTTNG_ERR_UST_LIST_FAIL;
2607 goto error;
2608 }
2609 break;
2610 }
2611 case LTTNG_DOMAIN_LOG4J:
2612 case LTTNG_DOMAIN_JUL:
2613 case LTTNG_DOMAIN_PYTHON:
2614 default:
2615 ret = LTTNG_ERR_UND;
2616 goto error;
2617 }
2618
2619 return nr_pids;
2620
2621 error:
2622 /* Return negative value to differentiate return code */
2623 return -ret;
2624 }
2625
2626 /*
2627 * Command LTTNG_START_TRACE processed by the client thread.
2628 *
2629 * Called with session mutex held.
2630 */
2631 int cmd_start_trace(struct ltt_session *session)
2632 {
2633 enum lttng_error_code ret;
2634 unsigned long nb_chan = 0;
2635 struct ltt_kernel_session *ksession;
2636 struct ltt_ust_session *usess;
2637 const bool session_rotated_after_last_stop =
2638 session->rotated_after_last_stop;
2639
2640 assert(session);
2641
2642 /* Ease our life a bit ;) */
2643 ksession = session->kernel_session;
2644 usess = session->ust_session;
2645
2646 /* Is the session already started? */
2647 if (session->active) {
2648 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2649 goto error;
2650 }
2651
2652 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING &&
2653 !session->current_trace_chunk) {
2654 /*
2655 * A rotation was launched while the session was stopped and
2656 * it has not been completed yet. It is not possible to start
2657 * the session since starting the session here would require a
2658 * rotation from "NULL" to a new trace chunk. That rotation
2659 * would overlap with the ongoing rotation, which is not
2660 * supported.
2661 */
2662 WARN("Refusing to start session \"%s\" as a rotation launched after the last \"stop\" is still ongoing",
2663 session->name);
2664 ret = LTTNG_ERR_ROTATION_PENDING;
2665 goto error;
2666 }
2667
2668 /*
2669 * Starting a session without channel is useless since after that it's not
2670 * possible to enable channel thus inform the client.
2671 */
2672 if (usess && usess->domain_global.channels) {
2673 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2674 }
2675 if (ksession) {
2676 nb_chan += ksession->channel_count;
2677 }
2678 if (!nb_chan) {
2679 ret = LTTNG_ERR_NO_CHANNEL;
2680 goto error;
2681 }
2682
2683 session->active = 1;
2684 session->rotated_after_last_stop = false;
2685 if (session->output_traces && !session->current_trace_chunk) {
2686 if (!session->has_been_started) {
2687 struct lttng_trace_chunk *trace_chunk;
2688
2689 DBG("Creating initial trace chunk of session \"%s\"",
2690 session->name);
2691 trace_chunk = session_create_new_trace_chunk(
2692 session, NULL, NULL, NULL);
2693 if (!trace_chunk) {
2694 ret = LTTNG_ERR_CREATE_DIR_FAIL;
2695 goto error;
2696 }
2697 assert(!session->current_trace_chunk);
2698 ret = session_set_trace_chunk(session, trace_chunk,
2699 NULL);
2700 lttng_trace_chunk_put(trace_chunk);
2701 if (ret) {
2702 ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
2703 goto error;
2704 }
2705 } else {
2706 DBG("Rotating session \"%s\" from its current \"NULL\" trace chunk to a new chunk",
2707 session->name);
2708 /*
2709 * Rotate existing streams into the new chunk.
2710 * This is a "quiet" rotation has no client has
2711 * explicitly requested this operation.
2712 *
2713 * There is also no need to wait for the rotation
2714 * to complete as it will happen immediately. No data
2715 * was produced as the session was stopped, so the
2716 * rotation should happen on reception of the command.
2717 */
2718 ret = cmd_rotate_session(session, NULL, true);
2719 if (ret != LTTNG_OK) {
2720 goto error;
2721 }
2722 }
2723 }
2724
2725 /* Kernel tracing */
2726 if (ksession != NULL) {
2727 DBG("Start kernel tracing session %s", session->name);
2728 ret = start_kernel_session(ksession);
2729 if (ret != LTTNG_OK) {
2730 goto error;
2731 }
2732 }
2733
2734 /* Flag session that trace should start automatically */
2735 if (usess) {
2736 int int_ret = ust_app_start_trace_all(usess);
2737
2738 if (int_ret < 0) {
2739 ret = LTTNG_ERR_UST_START_FAIL;
2740 goto error;
2741 }
2742 }
2743
2744 /*
2745 * Clear the flag that indicates that a rotation was done while the
2746 * session was stopped.
2747 */
2748 session->rotated_after_last_stop = false;
2749
2750 if (session->rotate_timer_period) {
2751 int int_ret = timer_session_rotation_schedule_timer_start(
2752 session, session->rotate_timer_period);
2753
2754 if (int_ret < 0) {
2755 ERR("Failed to enable rotate timer");
2756 ret = LTTNG_ERR_UNK;
2757 goto error;
2758 }
2759 }
2760
2761 ret = LTTNG_OK;
2762
2763 error:
2764 if (ret == LTTNG_OK) {
2765 /* Flag this after a successful start. */
2766 session->has_been_started |= 1;
2767 } else {
2768 session->active = 0;
2769 /* Restore initial state on error. */
2770 session->rotated_after_last_stop =
2771 session_rotated_after_last_stop;
2772 }
2773 return ret;
2774 }
2775
2776 /*
2777 * Command LTTNG_STOP_TRACE processed by the client thread.
2778 */
2779 int cmd_stop_trace(struct ltt_session *session)
2780 {
2781 int ret;
2782 struct ltt_kernel_session *ksession;
2783 struct ltt_ust_session *usess;
2784
2785 assert(session);
2786
2787 DBG("Begin stop session \"%s\" (id %" PRIu64 ")", session->name, session->id);
2788 /* Short cut */
2789 ksession = session->kernel_session;
2790 usess = session->ust_session;
2791
2792 /* Session is not active. Skip everythong and inform the client. */
2793 if (!session->active) {
2794 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2795 goto error;
2796 }
2797
2798 ret = stop_kernel_session(ksession);
2799 if (ret != LTTNG_OK) {
2800 goto error;
2801 }
2802
2803 if (usess && usess->active) {
2804 ret = ust_app_stop_trace_all(usess);
2805 if (ret < 0) {
2806 ret = LTTNG_ERR_UST_STOP_FAIL;
2807 goto error;
2808 }
2809 }
2810
2811 DBG("Completed stop session \"%s\" (id %" PRIu64 ")", session->name,
2812 session->id);
2813 /* Flag inactive after a successful stop. */
2814 session->active = 0;
2815 ret = LTTNG_OK;
2816
2817 error:
2818 return ret;
2819 }
2820
2821 /*
2822 * Set the base_path of the session only if subdir of a control uris is set.
2823 * Return LTTNG_OK on success, otherwise LTTNG_ERR_*.
2824 */
2825 static int set_session_base_path_from_uris(struct ltt_session *session,
2826 size_t nb_uri,
2827 struct lttng_uri *uris)
2828 {
2829 int ret;
2830 size_t i;
2831
2832 for (i = 0; i < nb_uri; i++) {
2833 if (uris[i].stype != LTTNG_STREAM_CONTROL ||
2834 uris[i].subdir[0] == '\0') {
2835 /* Not interested in these URIs */
2836 continue;
2837 }
2838
2839 if (session->base_path != NULL) {
2840 free(session->base_path);
2841 session->base_path = NULL;
2842 }
2843
2844 /* Set session base_path */
2845 session->base_path = strdup(uris[i].subdir);
2846 if (!session->base_path) {
2847 PERROR("Failed to copy base path \"%s\" to session \"%s\"",
2848 uris[i].subdir, session->name);
2849 ret = LTTNG_ERR_NOMEM;
2850 goto error;
2851 }
2852 DBG2("Setting base path \"%s\" for session \"%s\"",
2853 session->base_path, session->name);
2854 }
2855 ret = LTTNG_OK;
2856 error:
2857 return ret;
2858 }
2859
2860 /*
2861 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2862 */
2863 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2864 struct lttng_uri *uris)
2865 {
2866 int ret, i;
2867 struct ltt_kernel_session *ksess = session->kernel_session;
2868 struct ltt_ust_session *usess = session->ust_session;
2869
2870 assert(session);
2871 assert(uris);
2872 assert(nb_uri > 0);
2873
2874 /* Can't set consumer URI if the session is active. */
2875 if (session->active) {
2876 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2877 goto error;
2878 }
2879
2880 /*
2881 * Set the session base path if any. This is done inside
2882 * cmd_set_consumer_uri to preserve backward compatibility of the
2883 * previous session creation api vs the session descriptor api.
2884 */
2885 ret = set_session_base_path_from_uris(session, nb_uri, uris);
2886 if (ret != LTTNG_OK) {
2887 goto error;
2888 }
2889
2890 /* Set the "global" consumer URIs */
2891 for (i = 0; i < nb_uri; i++) {
2892 ret = add_uri_to_consumer(session, session->consumer, &uris[i],
2893 LTTNG_DOMAIN_NONE);
2894 if (ret != LTTNG_OK) {
2895 goto error;
2896 }
2897 }
2898
2899 /* Set UST session URIs */
2900 if (session->ust_session) {
2901 for (i = 0; i < nb_uri; i++) {
2902 ret = add_uri_to_consumer(session,
2903 session->ust_session->consumer,
2904 &uris[i], LTTNG_DOMAIN_UST);
2905 if (ret != LTTNG_OK) {
2906 goto error;
2907 }
2908 }
2909 }
2910
2911 /* Set kernel session URIs */
2912 if (session->kernel_session) {
2913 for (i = 0; i < nb_uri; i++) {
2914 ret = add_uri_to_consumer(session,
2915 session->kernel_session->consumer,
2916 &uris[i], LTTNG_DOMAIN_KERNEL);
2917 if (ret != LTTNG_OK) {
2918 goto error;
2919 }
2920 }
2921 }
2922
2923 /*
2924 * Make sure to set the session in output mode after we set URI since a
2925 * session can be created without URL (thus flagged in no output mode).
2926 */
2927 session->output_traces = 1;
2928 if (ksess) {
2929 ksess->output_traces = 1;
2930 }
2931
2932 if (usess) {
2933 usess->output_traces = 1;
2934 }
2935
2936 /* All good! */
2937 ret = LTTNG_OK;
2938
2939 error:
2940 return ret;
2941 }
2942
2943 static
2944 enum lttng_error_code set_session_output_from_descriptor(
2945 struct ltt_session *session,
2946 const struct lttng_session_descriptor *descriptor)
2947 {
2948 int ret;
2949 enum lttng_error_code ret_code = LTTNG_OK;
2950 enum lttng_session_descriptor_type session_type =
2951 lttng_session_descriptor_get_type(descriptor);
2952 enum lttng_session_descriptor_output_type output_type =
2953 lttng_session_descriptor_get_output_type(descriptor);
2954 struct lttng_uri uris[2] = {};
2955 size_t uri_count = 0;
2956
2957 switch (output_type) {
2958 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NONE:
2959 goto end;
2960 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_LOCAL:
2961 lttng_session_descriptor_get_local_output_uri(descriptor,
2962 &uris[0]);
2963 uri_count = 1;
2964 break;
2965 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NETWORK:
2966 lttng_session_descriptor_get_network_output_uris(descriptor,
2967 &uris[0], &uris[1]);
2968 uri_count = 2;
2969 break;
2970 default:
2971 ret_code = LTTNG_ERR_INVALID;
2972 goto end;
2973 }
2974
2975 switch (session_type) {
2976 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
2977 {
2978 struct snapshot_output *new_output = NULL;
2979
2980 new_output = snapshot_output_alloc();
2981 if (!new_output) {
2982 ret_code = LTTNG_ERR_NOMEM;
2983 goto end;
2984 }
2985
2986 ret = snapshot_output_init_with_uri(session,
2987 DEFAULT_SNAPSHOT_MAX_SIZE,
2988 NULL, uris, uri_count, session->consumer,
2989 new_output, &session->snapshot);
2990 if (ret < 0) {
2991 ret_code = (ret == -ENOMEM) ?
2992 LTTNG_ERR_NOMEM : LTTNG_ERR_INVALID;
2993 snapshot_output_destroy(new_output);
2994 goto end;
2995 }
2996 snapshot_add_output(&session->snapshot, new_output);
2997 break;
2998 }
2999 case LTTNG_SESSION_DESCRIPTOR_TYPE_REGULAR:
3000 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3001 {
3002 ret_code = cmd_set_consumer_uri(session, uri_count, uris);
3003 break;
3004 }
3005 default:
3006 ret_code = LTTNG_ERR_INVALID;
3007 goto end;
3008 }
3009 end:
3010 return ret_code;
3011 }
3012
3013 static
3014 enum lttng_error_code cmd_create_session_from_descriptor(
3015 struct lttng_session_descriptor *descriptor,
3016 const lttng_sock_cred *creds,
3017 const char *home_path)
3018 {
3019 int ret;
3020 enum lttng_error_code ret_code;
3021 const char *session_name;
3022 struct ltt_session *new_session = NULL;
3023 enum lttng_session_descriptor_status descriptor_status;
3024
3025 session_lock_list();
3026 if (home_path) {
3027 if (*home_path != '/') {
3028 ERR("Home path provided by client is not absolute");
3029 ret_code = LTTNG_ERR_INVALID;
3030 goto end;
3031 }
3032 }
3033
3034 descriptor_status = lttng_session_descriptor_get_session_name(
3035 descriptor, &session_name);
3036 switch (descriptor_status) {
3037 case LTTNG_SESSION_DESCRIPTOR_STATUS_OK:
3038 break;
3039 case LTTNG_SESSION_DESCRIPTOR_STATUS_UNSET:
3040 session_name = NULL;
3041 break;
3042 default:
3043 ret_code = LTTNG_ERR_INVALID;
3044 goto end;
3045 }
3046
3047 ret_code = session_create(session_name, creds->uid, creds->gid,
3048 &new_session);
3049 if (ret_code != LTTNG_OK) {
3050 goto end;
3051 }
3052
3053 if (!session_name) {
3054 ret = lttng_session_descriptor_set_session_name(descriptor,
3055 new_session->name);
3056 if (ret) {
3057 ret_code = LTTNG_ERR_SESSION_FAIL;
3058 goto end;
3059 }
3060 }
3061
3062 if (!lttng_session_descriptor_is_output_destination_initialized(
3063 descriptor)) {
3064 /*
3065 * Only include the session's creation time in the output
3066 * destination if the name of the session itself was
3067 * not auto-generated.
3068 */
3069 ret_code = lttng_session_descriptor_set_default_output(
3070 descriptor,
3071 session_name ? &new_session->creation_time : NULL,
3072 home_path);
3073 if (ret_code != LTTNG_OK) {
3074 goto end;
3075 }
3076 } else {
3077 new_session->has_user_specified_directory =
3078 lttng_session_descriptor_has_output_directory(
3079 descriptor);
3080 }
3081
3082 switch (lttng_session_descriptor_get_type(descriptor)) {
3083 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
3084 new_session->snapshot_mode = 1;
3085 break;
3086 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3087 new_session->live_timer =
3088 lttng_session_descriptor_live_get_timer_interval(
3089 descriptor);
3090 break;
3091 default:
3092 break;
3093 }
3094
3095 ret_code = set_session_output_from_descriptor(new_session, descriptor);
3096 if (ret_code != LTTNG_OK) {
3097 goto end;
3098 }
3099 new_session->consumer->enabled = 1;
3100 ret_code = LTTNG_OK;
3101 end:
3102 /* Release reference provided by the session_create function. */
3103 session_put(new_session);
3104 if (ret_code != LTTNG_OK && new_session) {
3105 /* Release the global reference on error. */
3106 session_destroy(new_session);
3107 }
3108 session_unlock_list();
3109 return ret_code;
3110 }
3111
3112 enum lttng_error_code cmd_create_session(struct command_ctx *cmd_ctx, int sock,
3113 struct lttng_session_descriptor **return_descriptor)
3114 {
3115 int ret;
3116 size_t payload_size;
3117 struct lttng_dynamic_buffer payload;
3118 struct lttng_buffer_view home_dir_view;
3119 struct lttng_buffer_view session_descriptor_view;
3120 struct lttng_session_descriptor *session_descriptor = NULL;
3121 enum lttng_error_code ret_code;
3122
3123 lttng_dynamic_buffer_init(&payload);
3124 if (cmd_ctx->lsm->u.create_session.home_dir_size >=
3125 LTTNG_PATH_MAX) {
3126 ret_code = LTTNG_ERR_INVALID;
3127 goto error;
3128 }
3129 if (cmd_ctx->lsm->u.create_session.session_descriptor_size >
3130 LTTNG_SESSION_DESCRIPTOR_MAX_LEN) {
3131 ret_code = LTTNG_ERR_INVALID;
3132 goto error;
3133 }
3134
3135 payload_size = cmd_ctx->lsm->u.create_session.home_dir_size +
3136 cmd_ctx->lsm->u.create_session.session_descriptor_size;
3137 ret = lttng_dynamic_buffer_set_size(&payload, payload_size);
3138 if (ret) {
3139 ret_code = LTTNG_ERR_NOMEM;
3140 goto error;
3141 }
3142
3143 ret = lttcomm_recv_unix_sock(sock, payload.data, payload.size);
3144 if (ret <= 0) {
3145 ERR("Reception of session descriptor failed, aborting.");
3146 ret_code = LTTNG_ERR_SESSION_FAIL;
3147 goto error;
3148 }
3149
3150 home_dir_view = lttng_buffer_view_from_dynamic_buffer(
3151 &payload,
3152 0,
3153 cmd_ctx->lsm->u.create_session.home_dir_size);
3154 session_descriptor_view = lttng_buffer_view_from_dynamic_buffer(
3155 &payload,
3156 cmd_ctx->lsm->u.create_session.home_dir_size,
3157 cmd_ctx->lsm->u.create_session.session_descriptor_size);
3158
3159 ret = lttng_session_descriptor_create_from_buffer(
3160 &session_descriptor_view, &session_descriptor);
3161 if (ret < 0) {
3162 ERR("Failed to create session descriptor from payload of \"create session\" command");
3163 ret_code = LTTNG_ERR_INVALID;
3164 goto error;
3165 }
3166
3167 /*
3168 * Sets the descriptor's auto-generated properties (name, output) if
3169 * needed.
3170 */
3171 ret_code = cmd_create_session_from_descriptor(session_descriptor,
3172 &cmd_ctx->creds,
3173 home_dir_view.size ? home_dir_view.data : NULL);
3174 if (ret_code != LTTNG_OK) {
3175 goto error;
3176 }
3177
3178 ret_code = LTTNG_OK;
3179 *return_descriptor = session_descriptor;
3180 session_descriptor = NULL;
3181 error:
3182 lttng_dynamic_buffer_reset(&payload);
3183 lttng_session_descriptor_destroy(session_descriptor);
3184 return ret_code;
3185 }
3186
3187 static
3188 void cmd_destroy_session_reply(const struct ltt_session *session,
3189 void *_reply_context)
3190 {
3191 int ret;
3192 ssize_t comm_ret;
3193 const struct cmd_destroy_session_reply_context *reply_context =
3194 _reply_context;
3195 struct lttng_dynamic_buffer payload;
3196 struct lttcomm_session_destroy_command_header cmd_header;
3197 struct lttng_trace_archive_location *location = NULL;
3198 struct lttcomm_lttng_msg llm = {
3199 .cmd_type = LTTNG_DESTROY_SESSION,
3200 .ret_code = reply_context->destruction_status,
3201 .pid = UINT32_MAX,
3202 .cmd_header_size =
3203 sizeof(struct lttcomm_session_destroy_command_header),
3204 .data_size = 0,
3205 };
3206 size_t payload_size_before_location;
3207
3208 lttng_dynamic_buffer_init(&payload);
3209
3210 ret = lttng_dynamic_buffer_append(&payload, &llm, sizeof(llm));
3211 if (ret) {
3212 ERR("Failed to append session destruction message");
3213 goto error;
3214 }
3215
3216 cmd_header.rotation_state =
3217 (int32_t) (reply_context->implicit_rotation_on_destroy ?
3218 session->rotation_state :
3219 LTTNG_ROTATION_STATE_NO_ROTATION);
3220 ret = lttng_dynamic_buffer_append(&payload, &cmd_header,
3221 sizeof(cmd_header));
3222 if (ret) {
3223 ERR("Failed to append session destruction command header");
3224 goto error;
3225 }
3226
3227 if (!reply_context->implicit_rotation_on_destroy) {
3228 DBG("No implicit rotation performed during the destruction of session \"%s\", sending reply",
3229 session->name);
3230 goto send_reply;
3231 }
3232 if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED) {
3233 DBG("Rotation state of session \"%s\" is not \"completed\", sending session destruction reply",
3234 session->name);
3235 goto send_reply;
3236 }
3237
3238 location = session_get_trace_archive_location(session);
3239 if (!location) {
3240 ERR("Failed to get the location of the trace archive produced during the destruction of session \"%s\"",
3241 session->name);
3242 goto error;
3243 }
3244
3245 payload_size_before_location = payload.size;
3246 comm_ret = lttng_trace_archive_location_serialize(location,
3247 &payload);
3248 if (comm_ret < 0) {
3249 ERR("Failed to serialize the location of the trace archive produced during the destruction of session \"%s\"",
3250 session->name);
3251 goto error;
3252 }
3253 /* Update the message to indicate the location's length. */
3254 ((struct lttcomm_lttng_msg *) payload.data)->data_size =
3255 payload.size - payload_size_before_location;
3256 send_reply:
3257 comm_ret = lttcomm_send_unix_sock(reply_context->reply_sock_fd,
3258 payload.data, payload.size);
3259 if (comm_ret != (ssize_t) payload.size) {
3260 ERR("Failed to send result of the destruction of session \"%s\" to client",
3261 session->name);
3262 }
3263 error:
3264 ret = close(reply_context->reply_sock_fd);
3265 if (ret) {
3266 PERROR("Failed to close client socket in deferred session destroy reply");
3267 }
3268 lttng_dynamic_buffer_reset(&payload);
3269 free(_reply_context);
3270 }
3271
3272 /*
3273 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3274 *
3275 * Called with session lock held.
3276 */
3277 int cmd_destroy_session(struct ltt_session *session,
3278 struct notification_thread_handle *notification_thread_handle,
3279 int *sock_fd)
3280 {
3281 int ret;
3282 enum lttng_error_code destruction_last_error = LTTNG_OK;
3283 struct cmd_destroy_session_reply_context *reply_context = NULL;
3284
3285 if (sock_fd) {
3286 reply_context = zmalloc(sizeof(*reply_context));
3287 if (!reply_context) {
3288 ret = LTTNG_ERR_NOMEM;
3289 goto end;
3290 }
3291 reply_context->reply_sock_fd = *sock_fd;
3292 }
3293
3294 /* Safety net */
3295 assert(session);
3296
3297 DBG("Begin destroy session %s (id %" PRIu64 ")", session->name,
3298 session->id);
3299 if (session->active) {
3300 DBG("Session \"%s\" is active, attempting to stop it before destroying it",
3301 session->name);
3302 ret = cmd_stop_trace(session);
3303 if (ret != LTTNG_OK && ret != LTTNG_ERR_TRACE_ALREADY_STOPPED) {
3304 /* Carry on with the destruction of the session. */
3305 ERR("Failed to stop session \"%s\" as part of its destruction: %s",
3306 session->name, lttng_strerror(-ret));
3307 destruction_last_error = ret;
3308 }
3309 }
3310
3311 if (session->rotation_schedule_timer_enabled) {
3312 if (timer_session_rotation_schedule_timer_stop(
3313 session)) {
3314 ERR("Failed to stop the \"rotation schedule\" timer of session %s",
3315 session->name);
3316 destruction_last_error = LTTNG_ERR_TIMER_STOP_ERROR;
3317 }
3318 }
3319
3320 if (session->rotate_size) {
3321 unsubscribe_session_consumed_size_rotation(session, notification_thread_handle);
3322 session->rotate_size = 0;
3323 }
3324
3325 if (session->most_recent_chunk_id.is_set &&
3326 session->most_recent_chunk_id.value != 0 &&
3327 session->current_trace_chunk && session->output_traces) {
3328 /*
3329 * Perform a last rotation on destruction if rotations have
3330 * occurred during the session's lifetime.
3331 */
3332 ret = cmd_rotate_session(session, NULL, false);
3333 if (ret != LTTNG_OK) {
3334 ERR("Failed to perform an implicit rotation as part of the destruction of session \"%s\": %s",
3335 session->name, lttng_strerror(-ret));
3336 destruction_last_error = -ret;
3337 }
3338 if (reply_context) {
3339 reply_context->implicit_rotation_on_destroy = true;
3340 }
3341 } else if (session->has_been_started && session->current_trace_chunk) {
3342 /*
3343 * The user has not triggered a session rotation. However, to
3344 * ensure all data has been consumed, the session is rotated
3345 * to a 'null' trace chunk before it is destroyed.
3346 *
3347 * This is a "quiet" rotation meaning that no notification is
3348 * emitted and no renaming of the current trace chunk takes
3349 * place.
3350 */
3351 ret = cmd_rotate_session(session, NULL, true);
3352 if (ret != LTTNG_OK) {
3353 ERR("Failed to perform a quiet rotation as part of the destruction of session \"%s\": %s",
3354 session->name, lttng_strerror(-ret));
3355 destruction_last_error = -ret;
3356 }
3357 }
3358
3359 if (session->shm_path[0]) {
3360 /*
3361 * When a session is created with an explicit shm_path,
3362 * the consumer daemon will create its shared memory files
3363 * at that location and will *not* unlink them. This is normal
3364 * as the intention of that feature is to make it possible
3365 * to retrieve the content of those files should a crash occur.
3366 *
3367 * To ensure the content of those files can be used, the
3368 * sessiond daemon will replicate the content of the metadata
3369 * cache in a metadata file.
3370 *
3371 * On clean-up, it is expected that the consumer daemon will
3372 * unlink the shared memory files and that the session daemon
3373 * will unlink the metadata file. Then, the session's directory
3374 * in the shm path can be removed.
3375 *
3376 * Unfortunately, a flaw in the design of the sessiond's and
3377 * consumerd's tear down of channels makes it impossible to
3378 * determine when the sessiond _and_ the consumerd have both
3379 * destroyed their representation of a channel. For one, the
3380 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3381 * callbacks in both daemons.
3382 *
3383 * However, it is also impossible for the sessiond to know when
3384 * the consumer daemon is done destroying its channel(s) since
3385 * it occurs as a reaction to the closing of the channel's file
3386 * descriptor. There is no resulting communication initiated
3387 * from the consumerd to the sessiond to confirm that the
3388 * operation is completed (and was successful).
3389 *
3390 * Until this is all fixed, the session daemon checks for the
3391 * removal of the session's shm path which makes it possible
3392 * to safely advertise a session as having been destroyed.
3393 *
3394 * Prior to this fix, it was not possible to reliably save
3395 * a session making use of the --shm-path option, destroy it,
3396 * and load it again. This is because the creation of the
3397 * session would fail upon seeing the session's shm path
3398 * already in existence.
3399 *
3400 * Note that none of the error paths in the check for the
3401 * directory's existence return an error. This is normal
3402 * as there isn't much that can be done. The session will
3403 * be destroyed properly, except that we can't offer the
3404 * guarantee that the same session can be re-created.
3405 */
3406 current_completion_handler = &destroy_completion_handler.handler;
3407 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3408 session->shm_path,
3409 sizeof(destroy_completion_handler.shm_path));
3410 assert(!ret);
3411 }
3412
3413 /*
3414 * The session is destroyed. However, note that the command context
3415 * still holds a reference to the session, thus delaying its destruction
3416 * _at least_ up to the point when that reference is released.
3417 */
3418 session_destroy(session);
3419 if (reply_context) {
3420 reply_context->destruction_status = destruction_last_error;
3421 ret = session_add_destroy_notifier(session,
3422 cmd_destroy_session_reply,
3423 (void *) reply_context);
3424 if (ret) {
3425 ret = LTTNG_ERR_FATAL;
3426 goto end;
3427 } else {
3428 *sock_fd = -1;
3429 }
3430 }
3431 ret = LTTNG_OK;
3432 end:
3433 return ret;
3434 }
3435
3436 /*
3437 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3438 */
3439 int cmd_register_consumer(struct ltt_session *session,
3440 enum lttng_domain_type domain, const char *sock_path,
3441 struct consumer_data *cdata)
3442 {
3443 int ret, sock;
3444 struct consumer_socket *socket = NULL;
3445
3446 assert(session);
3447 assert(cdata);
3448 assert(sock_path);
3449
3450 switch (domain) {
3451 case LTTNG_DOMAIN_KERNEL:
3452 {
3453 struct ltt_kernel_session *ksess = session->kernel_session;
3454
3455 assert(ksess);
3456
3457 /* Can't register a consumer if there is already one */
3458 if (ksess->consumer_fds_sent != 0) {
3459 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3460 goto error;
3461 }
3462
3463 sock = lttcomm_connect_unix_sock(sock_path);
3464 if (sock < 0) {
3465 ret = LTTNG_ERR_CONNECT_FAIL;
3466 goto error;
3467 }
3468 cdata->cmd_sock = sock;
3469
3470 socket = consumer_allocate_socket(&cdata->cmd_sock);
3471 if (socket == NULL) {
3472 ret = close(sock);
3473 if (ret < 0) {
3474 PERROR("close register consumer");
3475 }
3476 cdata->cmd_sock = -1;
3477 ret = LTTNG_ERR_FATAL;
3478 goto error;
3479 }
3480
3481 socket->lock = zmalloc(sizeof(pthread_mutex_t));
3482 if (socket->lock == NULL) {
3483 PERROR("zmalloc pthread mutex");
3484 ret = LTTNG_ERR_FATAL;
3485 goto error;
3486 }
3487 pthread_mutex_init(socket->lock, NULL);
3488 socket->registered = 1;
3489
3490 rcu_read_lock();
3491 consumer_add_socket(socket, ksess->consumer);
3492 rcu_read_unlock();
3493
3494 pthread_mutex_lock(&cdata->pid_mutex);
3495 cdata->pid = -1;
3496 pthread_mutex_unlock(&cdata->pid_mutex);
3497
3498 break;
3499 }
3500 default:
3501 /* TODO: Userspace tracing */
3502 ret = LTTNG_ERR_UND;
3503 goto error;
3504 }
3505
3506 return LTTNG_OK;
3507
3508 error:
3509 if (socket) {
3510 consumer_destroy_socket(socket);
3511 }
3512 return ret;
3513 }
3514
3515 /*
3516 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3517 */
3518 ssize_t cmd_list_domains(struct ltt_session *session,
3519 struct lttng_domain **domains)
3520 {
3521 int ret, index = 0;
3522 ssize_t nb_dom = 0;
3523 struct agent *agt;
3524 struct lttng_ht_iter iter;
3525
3526 if (session->kernel_session != NULL) {
3527 DBG3("Listing domains found kernel domain");
3528 nb_dom++;
3529 }
3530
3531 if (session->ust_session != NULL) {
3532 DBG3("Listing domains found UST global domain");
3533 nb_dom++;
3534
3535 rcu_read_lock();
3536 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3537 agt, node.node) {
3538 if (agt->being_used) {
3539 nb_dom++;
3540 }
3541 }
3542 rcu_read_unlock();
3543 }
3544
3545 if (!nb_dom) {
3546 goto end;
3547 }
3548
3549 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3550 if (*domains == NULL) {
3551 ret = LTTNG_ERR_FATAL;
3552 goto error;
3553 }
3554
3555 if (session->kernel_session != NULL) {
3556 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3557
3558 /* Kernel session buffer type is always GLOBAL */
3559 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3560
3561 index++;
3562 }
3563
3564 if (session->ust_session != NULL) {
3565 (*domains)[index].type = LTTNG_DOMAIN_UST;
3566 (*domains)[index].buf_type = session->ust_session->buffer_type;
3567 index++;
3568
3569 rcu_read_lock();
3570 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3571 agt, node.node) {
3572 if (agt->being_used) {
3573 (*domains)[index].type = agt->domain;
3574 (*domains)[index].buf_type = session->ust_session->buffer_type;
3575 index++;
3576 }
3577 }
3578 rcu_read_unlock();
3579 }
3580 end:
3581 return nb_dom;
3582
3583 error:
3584 /* Return negative value to differentiate return code */
3585 return -ret;
3586 }
3587
3588
3589 /*
3590 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3591 */
3592 ssize_t cmd_list_channels(enum lttng_domain_type domain,
3593 struct ltt_session *session, struct lttng_channel **channels)
3594 {
3595 ssize_t nb_chan = 0, payload_size = 0, ret;
3596
3597 switch (domain) {
3598 case LTTNG_DOMAIN_KERNEL:
3599 if (session->kernel_session != NULL) {
3600 nb_chan = session->kernel_session->channel_count;
3601 }
3602 DBG3("Number of kernel channels %zd", nb_chan);
3603 if (nb_chan <= 0) {
3604 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
3605 goto end;
3606 }
3607 break;
3608 case LTTNG_DOMAIN_UST:
3609 if (session->ust_session != NULL) {
3610 rcu_read_lock();
3611 nb_chan = lttng_ht_get_count(
3612 session->ust_session->domain_global.channels);
3613 rcu_read_unlock();
3614 }
3615 DBG3("Number of UST global channels %zd", nb_chan);
3616 if (nb_chan < 0) {
3617 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
3618 goto end;
3619 }
3620 break;
3621 default:
3622 ret = -LTTNG_ERR_UND;
3623 goto end;
3624 }
3625
3626 if (nb_chan > 0) {
3627 const size_t channel_size = sizeof(struct lttng_channel) +
3628 sizeof(struct lttng_channel_extended);
3629 struct lttng_channel_extended *channel_exts;
3630
3631 payload_size = nb_chan * channel_size;
3632 *channels = zmalloc(payload_size);
3633 if (*channels == NULL) {
3634 ret = -LTTNG_ERR_FATAL;
3635 goto end;
3636 }
3637
3638 channel_exts = ((void *) *channels) +
3639 (nb_chan * sizeof(struct lttng_channel));
3640 ret = list_lttng_channels(domain, session, *channels, channel_exts);
3641 if (ret != LTTNG_OK) {
3642 free(*channels);
3643 *channels = NULL;
3644 goto end;
3645 }
3646 } else {
3647 *channels = NULL;
3648 }
3649
3650 ret = payload_size;
3651 end:
3652 return ret;
3653 }
3654
3655 /*
3656 * Command LTTNG_LIST_EVENTS processed by the client thread.
3657 */
3658 ssize_t cmd_list_events(enum lttng_domain_type domain,
3659 struct ltt_session *session, char *channel_name,
3660 struct lttng_event **events, size_t *total_size)
3661 {
3662 int ret = 0;
3663 ssize_t nb_event = 0;
3664
3665 switch (domain) {
3666 case LTTNG_DOMAIN_KERNEL:
3667 if (session->kernel_session != NULL) {
3668 nb_event = list_lttng_kernel_events(channel_name,
3669 session->kernel_session, events,
3670 total_size);
3671 }
3672 break;
3673 case LTTNG_DOMAIN_UST:
3674 {
3675 if (session->ust_session != NULL) {
3676 nb_event = list_lttng_ust_global_events(channel_name,
3677 &session->ust_session->domain_global, events,
3678 total_size);
3679 }
3680 break;
3681 }
3682 case LTTNG_DOMAIN_LOG4J:
3683 case LTTNG_DOMAIN_JUL:
3684 case LTTNG_DOMAIN_PYTHON:
3685 if (session->ust_session) {
3686 struct lttng_ht_iter iter;
3687 struct agent *agt;
3688
3689 rcu_read_lock();
3690 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3691 &iter.iter, agt, node.node) {
3692 if (agt->domain == domain) {
3693 nb_event = list_lttng_agent_events(
3694 agt, events,
3695 total_size);
3696 break;
3697 }
3698 }
3699 rcu_read_unlock();
3700 }
3701 break;
3702 default:
3703 ret = LTTNG_ERR_UND;
3704 goto error;
3705 }
3706
3707 return nb_event;
3708
3709 error:
3710 /* Return negative value to differentiate return code */
3711 return -ret;
3712 }
3713
3714 /*
3715 * Using the session list, filled a lttng_session array to send back to the
3716 * client for session listing.
3717 *
3718 * The session list lock MUST be acquired before calling this function. Use
3719 * session_lock_list() and session_unlock_list().
3720 */
3721 void cmd_list_lttng_sessions(struct lttng_session *sessions,
3722 size_t session_count, uid_t uid, gid_t gid)
3723 {
3724 int ret;
3725 unsigned int i = 0;
3726 struct ltt_session *session;
3727 struct ltt_session_list *list = session_get_list();
3728 struct lttng_session_extended *extended =
3729 (typeof(extended)) (&sessions[session_count]);
3730
3731 DBG("Getting all available session for UID %d GID %d",
3732 uid, gid);
3733 /*
3734 * Iterate over session list and append data after the control struct in
3735 * the buffer.
3736 */
3737 cds_list_for_each_entry(session, &list->head, list) {
3738 if (!session_get(session)) {
3739 continue;
3740 }
3741 /*
3742 * Only list the sessions the user can control.
3743 */
3744 if (!session_access_ok(session, uid, gid) ||
3745 session->destroyed) {
3746 session_put(session);
3747 continue;
3748 }
3749
3750 struct ltt_kernel_session *ksess = session->kernel_session;
3751 struct ltt_ust_session *usess = session->ust_session;
3752
3753 if (session->consumer->type == CONSUMER_DST_NET ||
3754 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3755 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3756 ret = build_network_session_path(sessions[i].path,
3757 sizeof(sessions[i].path), session);
3758 } else {
3759 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3760 session->consumer->dst.session_root_path);
3761 }
3762 if (ret < 0) {
3763 PERROR("snprintf session path");
3764 session_put(session);
3765 continue;
3766 }
3767
3768 strncpy(sessions[i].name, session->name, NAME_MAX);
3769 sessions[i].name[NAME_MAX - 1] = '\0';
3770 sessions[i].enabled = session->active;
3771 sessions[i].snapshot_mode = session->snapshot_mode;
3772 sessions[i].live_timer_interval = session->live_timer;
3773 extended[i].creation_time.value = (uint64_t) session->creation_time;
3774 extended[i].creation_time.is_set = 1;
3775 i++;
3776 session_put(session);
3777 }
3778 }
3779
3780 /*
3781 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3782 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3783 */
3784 int cmd_data_pending(struct ltt_session *session)
3785 {
3786 int ret;
3787 struct ltt_kernel_session *ksess = session->kernel_session;
3788 struct ltt_ust_session *usess = session->ust_session;
3789
3790 assert(session);
3791
3792 DBG("Data pending for session %s", session->name);
3793
3794 /* Session MUST be stopped to ask for data availability. */
3795 if (session->active) {
3796 ret = LTTNG_ERR_SESSION_STARTED;
3797 goto error;
3798 } else {
3799 /*
3800 * If stopped, just make sure we've started before else the above call
3801 * will always send that there is data pending.
3802 *
3803 * The consumer assumes that when the data pending command is received,
3804 * the trace has been started before or else no output data is written
3805 * by the streams which is a condition for data pending. So, this is
3806 * *VERY* important that we don't ask the consumer before a start
3807 * trace.
3808 */
3809 if (!session->has_been_started) {
3810 ret = 0;
3811 goto error;
3812 }
3813 }
3814
3815 /* A rotation is still pending, we have to wait. */
3816 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
3817 DBG("Rotate still pending for session %s", session->name);
3818 ret = 1;
3819 goto error;
3820 }
3821
3822 if (ksess && ksess->consumer) {
3823 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3824 if (ret == 1) {
3825 /* Data is still being extracted for the kernel. */
3826 goto error;
3827 }
3828 }
3829
3830 if (usess && usess->consumer) {
3831 ret = consumer_is_data_pending(usess->id, usess->consumer);
3832 if (ret == 1) {
3833 /* Data is still being extracted for the kernel. */
3834 goto error;
3835 }
3836 }
3837
3838 /* Data is ready to be read by a viewer */
3839 ret = 0;
3840
3841 error:
3842 return ret;
3843 }
3844
3845 /*
3846 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3847 *
3848 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3849 */
3850 int cmd_snapshot_add_output(struct ltt_session *session,
3851 const struct lttng_snapshot_output *output, uint32_t *id)
3852 {
3853 int ret;
3854 struct snapshot_output *new_output;
3855
3856 assert(session);
3857 assert(output);
3858
3859 DBG("Cmd snapshot add output for session %s", session->name);
3860
3861 /*
3862 * Can't create an output if the session is not set in no-output mode.
3863 */
3864 if (session->output_traces) {
3865 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3866 goto error;
3867 }
3868
3869 if (session->has_non_mmap_channel) {
3870 ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
3871 goto error;
3872 }
3873
3874 /* Only one output is allowed until we have the "tee" feature. */
3875 if (session->snapshot.nb_output == 1) {
3876 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3877 goto error;
3878 }
3879
3880 new_output = snapshot_output_alloc();
3881 if (!new_output) {
3882 ret = LTTNG_ERR_NOMEM;
3883 goto error;
3884 }
3885
3886 ret = snapshot_output_init(session, output->max_size, output->name,
3887 output->ctrl_url, output->data_url, session->consumer, new_output,
3888 &session->snapshot);
3889 if (ret < 0) {
3890 if (ret == -ENOMEM) {
3891 ret = LTTNG_ERR_NOMEM;
3892 } else {
3893 ret = LTTNG_ERR_INVALID;
3894 }
3895 goto free_error;
3896 }
3897
3898 rcu_read_lock();
3899 snapshot_add_output(&session->snapshot, new_output);
3900 if (id) {
3901 *id = new_output->id;
3902 }
3903 rcu_read_unlock();
3904
3905 return LTTNG_OK;
3906
3907 free_error:
3908 snapshot_output_destroy(new_output);
3909 error:
3910 return ret;
3911 }
3912
3913 /*
3914 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3915 *
3916 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3917 */
3918 int cmd_snapshot_del_output(struct ltt_session *session,
3919 const struct lttng_snapshot_output *output)
3920 {
3921 int ret;
3922 struct snapshot_output *sout = NULL;
3923
3924 assert(session);
3925 assert(output);
3926
3927 rcu_read_lock();
3928
3929 /*
3930 * Permission denied to create an output if the session is not
3931 * set in no output mode.
3932 */
3933 if (session->output_traces) {
3934 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3935 goto error;
3936 }
3937
3938 if (output->id) {
3939 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
3940 session->name);
3941 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
3942 } else if (*output->name != '\0') {
3943 DBG("Cmd snapshot del output name %s for session %s", output->name,
3944 session->name);
3945 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
3946 }
3947 if (!sout) {
3948 ret = LTTNG_ERR_INVALID;
3949 goto error;
3950 }
3951
3952 snapshot_delete_output(&session->snapshot, sout);
3953 snapshot_output_destroy(sout);
3954 ret = LTTNG_OK;
3955
3956 error:
3957 rcu_read_unlock();
3958 return ret;
3959 }
3960
3961 /*
3962 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
3963 *
3964 * If no output is available, outputs is untouched and 0 is returned.
3965 *
3966 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
3967 */
3968 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
3969 struct lttng_snapshot_output **outputs)
3970 {
3971 int ret, idx = 0;
3972 struct lttng_snapshot_output *list = NULL;
3973 struct lttng_ht_iter iter;
3974 struct snapshot_output *output;
3975
3976 assert(session);
3977 assert(outputs);
3978
3979 DBG("Cmd snapshot list outputs for session %s", session->name);
3980
3981 /*
3982 * Permission denied to create an output if the session is not
3983 * set in no output mode.
3984 */
3985 if (session->output_traces) {
3986 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3987 goto end;
3988 }
3989
3990 if (session->snapshot.nb_output == 0) {
3991 ret = 0;
3992 goto end;
3993 }
3994
3995 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
3996 if (!list) {
3997 ret = -LTTNG_ERR_NOMEM;
3998 goto end;
3999 }
4000
4001 /* Copy list from session to the new list object. */
4002 rcu_read_lock();
4003 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
4004 output, node.node) {
4005 assert(output->consumer);
4006 list[idx].id = output->id;
4007 list[idx].max_size = output->max_size;
4008 if (lttng_strncpy(list[idx].name, output->name,
4009 sizeof(list[idx].name))) {
4010 ret = -LTTNG_ERR_INVALID;
4011 goto error;
4012 }
4013 if (output->consumer->type == CONSUMER_DST_LOCAL) {
4014 if (lttng_strncpy(list[idx].ctrl_url,
4015 output->consumer->dst.session_root_path,
4016 sizeof(list[idx].ctrl_url))) {
4017 ret = -LTTNG_ERR_INVALID;
4018 goto error;
4019 }
4020 } else {
4021 /* Control URI. */
4022 ret = uri_to_str_url(&output->consumer->dst.net.control,
4023 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
4024 if (ret < 0) {
4025 ret = -LTTNG_ERR_NOMEM;
4026 goto error;
4027 }
4028
4029 /* Data URI. */
4030 ret = uri_to_str_url(&output->consumer->dst.net.data,
4031 list[idx].data_url, sizeof(list[idx].data_url));
4032 if (ret < 0) {
4033 ret = -LTTNG_ERR_NOMEM;
4034 goto error;
4035 }
4036 }
4037 idx++;
4038 }
4039
4040 *outputs = list;
4041 list = NULL;
4042 ret = session->snapshot.nb_output;
4043 error:
4044 rcu_read_unlock();
4045 free(list);
4046 end:
4047 return ret;
4048 }
4049
4050 /*
4051 * Check if we can regenerate the metadata for this session.
4052 * Only kernel, UST per-uid and non-live sessions are supported.
4053 *
4054 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
4055 */
4056 static
4057 int check_regenerate_metadata_support(struct ltt_session *session)
4058 {
4059 int ret;
4060
4061 assert(session);
4062
4063 if (session->live_timer != 0) {
4064 ret = LTTNG_ERR_LIVE_SESSION;
4065 goto end;
4066 }
4067 if (!session->active) {
4068 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4069 goto end;
4070 }
4071 if (session->ust_session) {
4072 switch (session->ust_session->buffer_type) {
4073 case LTTNG_BUFFER_PER_UID:
4074 break;
4075 case LTTNG_BUFFER_PER_PID:
4076 ret = LTTNG_ERR_PER_PID_SESSION;
4077 goto end;
4078 default:
4079 assert(0);
4080 ret = LTTNG_ERR_UNK;
4081 goto end;
4082 }
4083 }
4084 if (session->consumer->type == CONSUMER_DST_NET &&
4085 session->consumer->relay_minor_version < 8) {
4086 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
4087 goto end;
4088 }
4089 ret = 0;
4090
4091 end:
4092 return ret;
4093 }
4094
4095 static
4096 int clear_metadata_file(int fd)
4097 {
4098 int ret;
4099 off_t lseek_ret;
4100
4101 lseek_ret = lseek(fd, 0, SEEK_SET);
4102 if (lseek_ret < 0) {
4103 PERROR("lseek");
4104 ret = -1;
4105 goto end;
4106 }
4107
4108 ret = ftruncate(fd, 0);
4109 if (ret < 0) {
4110 PERROR("ftruncate");
4111 goto end;
4112 }
4113
4114 end:
4115 return ret;
4116 }
4117
4118 static
4119 int ust_regenerate_metadata(struct ltt_ust_session *usess)
4120 {
4121 int ret = 0;
4122 struct buffer_reg_uid *uid_reg = NULL;
4123 struct buffer_reg_session *session_reg = NULL;
4124
4125 rcu_read_lock();
4126 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
4127 struct ust_registry_session *registry;
4128 struct ust_registry_channel *chan;
4129 struct lttng_ht_iter iter_chan;
4130
4131 session_reg = uid_reg->registry;
4132 registry = session_reg->reg.ust;
4133
4134 pthread_mutex_lock(&registry->lock);
4135 registry->metadata_len_sent = 0;
4136 memset(registry->metadata, 0, registry->metadata_alloc_len);
4137 registry->metadata_len = 0;
4138 registry->metadata_version++;
4139 if (registry->metadata_fd > 0) {
4140 /* Clear the metadata file's content. */
4141 ret = clear_metadata_file(registry->metadata_fd);
4142 if (ret) {
4143 pthread_mutex_unlock(&registry->lock);
4144 goto end;
4145 }
4146 }
4147
4148 ret = ust_metadata_session_statedump(registry, NULL,
4149 registry->major, registry->minor);
4150 if (ret) {
4151 pthread_mutex_unlock(&registry->lock);
4152 ERR("Failed to generate session metadata (err = %d)",
4153 ret);
4154 goto end;
4155 }
4156 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
4157 chan, node.node) {
4158 struct ust_registry_event *event;
4159 struct lttng_ht_iter iter_event;
4160
4161 ret = ust_metadata_channel_statedump(registry, chan);
4162 if (ret) {
4163 pthread_mutex_unlock(&registry->lock);
4164 ERR("Failed to generate channel metadata "
4165 "(err = %d)", ret);
4166 goto end;
4167 }
4168 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
4169 event, node.node) {
4170 ret = ust_metadata_event_statedump(registry,
4171 chan, event);
4172 if (ret) {
4173 pthread_mutex_unlock(&registry->lock);
4174 ERR("Failed to generate event metadata "
4175 "(err = %d)", ret);
4176 goto end;
4177 }
4178 }
4179 }
4180 pthread_mutex_unlock(&registry->lock);
4181 }
4182
4183 end:
4184 rcu_read_unlock();
4185 return ret;
4186 }
4187
4188 /*
4189 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
4190 *
4191 * Ask the consumer to truncate the existing metadata file(s) and
4192 * then regenerate the metadata. Live and per-pid sessions are not
4193 * supported and return an error.
4194 *
4195 * Return 0 on success or else a LTTNG_ERR code.
4196 */
4197 int cmd_regenerate_metadata(struct ltt_session *session)
4198 {
4199 int ret;
4200
4201 assert(session);
4202
4203 ret = check_regenerate_metadata_support(session);
4204 if (ret) {
4205 goto end;
4206 }
4207
4208 if (session->kernel_session) {
4209 ret = kernctl_session_regenerate_metadata(
4210 session->kernel_session->fd);
4211 if (ret < 0) {
4212 ERR("Failed to regenerate the kernel metadata");
4213 goto end;
4214 }
4215 }
4216
4217 if (session->ust_session) {
4218 ret = ust_regenerate_metadata(session->ust_session);
4219 if (ret < 0) {
4220 ERR("Failed to regenerate the UST metadata");
4221 goto end;
4222 }
4223 }
4224 DBG("Cmd metadata regenerate for session %s", session->name);
4225 ret = LTTNG_OK;
4226
4227 end:
4228 return ret;
4229 }
4230
4231 /*
4232 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
4233 *
4234 * Ask the tracer to regenerate a new statedump.
4235 *
4236 * Return 0 on success or else a LTTNG_ERR code.
4237 */
4238 int cmd_regenerate_statedump(struct ltt_session *session)
4239 {
4240 int ret;
4241
4242 assert(session);
4243
4244 if (!session->active) {
4245 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4246 goto end;
4247 }
4248
4249 if (session->kernel_session) {
4250 ret = kernctl_session_regenerate_statedump(
4251 session->kernel_session->fd);
4252 /*
4253 * Currently, the statedump in kernel can only fail if out
4254 * of memory.
4255 */
4256 if (ret < 0) {
4257 if (ret == -ENOMEM) {
4258 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
4259 } else {
4260 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4261 }
4262 ERR("Failed to regenerate the kernel statedump");
4263 goto end;
4264 }
4265 }
4266
4267 if (session->ust_session) {
4268 ret = ust_app_regenerate_statedump_all(session->ust_session);
4269 /*
4270 * Currently, the statedump in UST always returns 0.
4271 */
4272 if (ret < 0) {
4273 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4274 ERR("Failed to regenerate the UST statedump");
4275 goto end;
4276 }
4277 }
4278 DBG("Cmd regenerate statedump for session %s", session->name);
4279 ret = LTTNG_OK;
4280
4281 end:
4282 return ret;
4283 }
4284
4285 int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
4286 struct notification_thread_handle *notification_thread)
4287 {
4288 int ret;
4289 size_t trigger_len;
4290 ssize_t sock_recv_len;
4291 struct lttng_trigger *trigger = NULL;
4292 struct lttng_buffer_view view;
4293 struct lttng_dynamic_buffer trigger_buffer;
4294
4295 lttng_dynamic_buffer_init(&trigger_buffer);
4296 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4297 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4298 if (ret) {
4299 ret = LTTNG_ERR_NOMEM;
4300 goto end;
4301 }
4302
4303 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4304 trigger_len);
4305 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4306 ERR("Failed to receive \"register trigger\" command payload");
4307 /* TODO: should this be a new error enum ? */
4308 ret = LTTNG_ERR_INVALID_TRIGGER;
4309 goto end;
4310 }
4311
4312 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4313 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4314 trigger_len) {
4315 ERR("Invalid trigger payload received in \"register trigger\" command");
4316 ret = LTTNG_ERR_INVALID_TRIGGER;
4317 goto end;
4318 }
4319
4320 ret = notification_thread_command_register_trigger(notification_thread,
4321 trigger);
4322 /* Ownership of trigger was transferred. */
4323 trigger = NULL;
4324 end:
4325 lttng_trigger_destroy(trigger);
4326 lttng_dynamic_buffer_reset(&trigger_buffer);
4327 return ret;
4328 }
4329
4330 int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
4331 struct notification_thread_handle *notification_thread)
4332 {
4333 int ret;
4334 size_t trigger_len;
4335 ssize_t sock_recv_len;
4336 struct lttng_trigger *trigger = NULL;
4337 struct lttng_buffer_view view;
4338 struct lttng_dynamic_buffer trigger_buffer;
4339
4340 lttng_dynamic_buffer_init(&trigger_buffer);
4341 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4342 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4343 if (ret) {
4344 ret = LTTNG_ERR_NOMEM;
4345 goto end;
4346 }
4347
4348 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4349 trigger_len);
4350 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4351 ERR("Failed to receive \"unregister trigger\" command payload");
4352 /* TODO: should this be a new error enum ? */
4353 ret = LTTNG_ERR_INVALID_TRIGGER;
4354 goto end;
4355 }
4356
4357 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4358 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4359 trigger_len) {
4360 ERR("Invalid trigger payload received in \"unregister trigger\" command");
4361 ret = LTTNG_ERR_INVALID_TRIGGER;
4362 goto end;
4363 }
4364
4365 ret = notification_thread_command_unregister_trigger(notification_thread,
4366 trigger);
4367 end:
4368 lttng_trigger_destroy(trigger);
4369 lttng_dynamic_buffer_reset(&trigger_buffer);
4370 return ret;
4371 }
4372
4373 /*
4374 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4375 * snapshot output is *not* set with a remote destination.
4376 *
4377 * Return LTTNG_OK on success or a LTTNG_ERR code.
4378 */
4379 static enum lttng_error_code set_relayd_for_snapshot(
4380 struct consumer_output *output,
4381 const struct ltt_session *session)
4382 {
4383 enum lttng_error_code status = LTTNG_OK;
4384 struct lttng_ht_iter iter;
4385 struct consumer_socket *socket;
4386 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
4387 const char *base_path;
4388
4389 assert(output);
4390 assert(session);
4391
4392 DBG2("Set relayd object from snapshot output");
4393
4394 if (session->current_trace_chunk) {
4395 enum lttng_trace_chunk_status chunk_status =
4396 lttng_trace_chunk_get_id(
4397 session->current_trace_chunk,
4398 &current_chunk_id.value);
4399
4400 if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK) {
4401 current_chunk_id.is_set = true;
4402 } else {
4403 ERR("Failed to get current trace chunk id");
4404 status = LTTNG_ERR_UNK;
4405 goto error;
4406 }
4407 }
4408
4409 /* Ignore if snapshot consumer output is not network. */
4410 if (output->type != CONSUMER_DST_NET) {
4411 goto error;
4412 }
4413
4414 /*
4415 * The snapshot record URI base path overrides the session
4416 * base path.
4417 */
4418 if (output->dst.net.control.subdir[0] != '\0') {
4419 base_path = output->dst.net.control.subdir;
4420 } else {
4421 base_path = session->base_path;
4422 }
4423
4424 /*
4425 * For each consumer socket, create and send the relayd object of the
4426 * snapshot output.
4427 */
4428 rcu_read_lock();
4429 cds_lfht_for_each_entry(output->socks->ht, &iter.iter,
4430 socket, node.node) {
4431 pthread_mutex_lock(socket->lock);
4432 status = send_consumer_relayd_sockets(0, session->id,
4433 output, socket,
4434 session->name, session->hostname,
4435 base_path,
4436 session->live_timer,
4437 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
4438 session->creation_time,
4439 session->name_contains_creation_time);
4440 pthread_mutex_unlock(socket->lock);
4441 if (status != LTTNG_OK) {
4442 rcu_read_unlock();
4443 goto error;
4444 }
4445 }
4446 rcu_read_unlock();
4447
4448 error:
4449 return status;
4450 }
4451
4452 /*
4453 * Record a kernel snapshot.
4454 *
4455 * Return LTTNG_OK on success or a LTTNG_ERR code.
4456 */
4457 static enum lttng_error_code record_kernel_snapshot(
4458 struct ltt_kernel_session *ksess,
4459 const struct consumer_output *output,
4460 const struct ltt_session *session,
4461 int wait, uint64_t nb_packets_per_stream)
4462 {
4463 enum lttng_error_code status;
4464
4465 assert(ksess);
4466 assert(output);
4467 assert(session);
4468
4469 status = kernel_snapshot_record(
4470 ksess, output, wait, nb_packets_per_stream);
4471 return status;
4472 }
4473
4474 /*
4475 * Record a UST snapshot.
4476 *
4477 * Returns LTTNG_OK on success or a LTTNG_ERR error code.
4478 */
4479 static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
4480 const struct consumer_output *output,
4481 const struct ltt_session *session,
4482 int wait, uint64_t nb_packets_per_stream)
4483 {
4484 enum lttng_error_code status;
4485
4486 assert(usess);
4487 assert(output);
4488 assert(session);
4489
4490 status = ust_app_snapshot_record(
4491 usess, output, wait, nb_packets_per_stream);
4492 return status;
4493 }
4494
4495 static
4496 uint64_t get_session_size_one_more_packet_per_stream(
4497 const struct ltt_session *session, uint64_t cur_nr_packets)
4498 {
4499 uint64_t tot_size = 0;
4500
4501 if (session->kernel_session) {
4502 struct ltt_kernel_channel *chan;
4503 const struct ltt_kernel_session *ksess =
4504 session->kernel_session;
4505
4506 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
4507 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
4508 /*
4509 * Don't take channel into account if we
4510 * already grab all its packets.
4511 */
4512 continue;
4513 }
4514 tot_size += chan->channel->attr.subbuf_size
4515 * chan->stream_count;
4516 }
4517 }
4518
4519 if (session->ust_session) {
4520 const struct ltt_ust_session *usess = session->ust_session;
4521
4522 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
4523 cur_nr_packets);
4524 }
4525
4526 return tot_size;
4527 }
4528
4529 /*
4530 * Calculate the number of packets we can grab from each stream that
4531 * fits within the overall snapshot max size.
4532 *
4533 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
4534 * the number of packets per stream.
4535 *
4536 * TODO: this approach is not perfect: we consider the worse case
4537 * (packet filling the sub-buffers) as an upper bound, but we could do
4538 * better if we do this calculation while we actually grab the packet
4539 * content: we would know how much padding we don't actually store into
4540 * the file.
4541 *
4542 * This algorithm is currently bounded by the number of packets per
4543 * stream.
4544 *
4545 * Since we call this algorithm before actually grabbing the data, it's
4546 * an approximation: for instance, applications could appear/disappear
4547 * in between this call and actually grabbing data.
4548 */
4549 static
4550 int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
4551 uint64_t max_size)
4552 {
4553 int64_t size_left;
4554 uint64_t cur_nb_packets = 0;
4555
4556 if (!max_size) {
4557 return 0; /* Infinite */
4558 }
4559
4560 size_left = max_size;
4561 for (;;) {
4562 uint64_t one_more_packet_tot_size;
4563
4564 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(
4565 session, cur_nb_packets);
4566 if (!one_more_packet_tot_size) {
4567 /* We are already grabbing all packets. */
4568 break;
4569 }
4570 size_left -= one_more_packet_tot_size;
4571 if (size_left < 0) {
4572 break;
4573 }
4574 cur_nb_packets++;
4575 }
4576 if (!cur_nb_packets) {
4577 /* Not enough room to grab one packet of each stream, error. */
4578 return -1;
4579 }
4580 return cur_nb_packets;
4581 }
4582
4583 static
4584 enum lttng_error_code snapshot_record(struct ltt_session *session,
4585 const struct snapshot_output *snapshot_output, int wait)
4586 {
4587 int64_t nb_packets_per_stream;
4588 char snapshot_chunk_name[LTTNG_NAME_MAX];
4589 int ret;
4590 enum lttng_error_code ret_code = LTTNG_OK;
4591 struct lttng_trace_chunk *snapshot_trace_chunk;
4592 struct consumer_output *original_ust_consumer_output = NULL;
4593 struct consumer_output *original_kernel_consumer_output = NULL;
4594 struct consumer_output *snapshot_ust_consumer_output = NULL;
4595 struct consumer_output *snapshot_kernel_consumer_output = NULL;
4596
4597 ret = snprintf(snapshot_chunk_name, sizeof(snapshot_chunk_name),
4598 "%s-%s-%" PRIu64,
4599 snapshot_output->name,
4600 snapshot_output->datetime,
4601 snapshot_output->nb_snapshot);
4602 if (ret < 0 || ret >= sizeof(snapshot_chunk_name)) {
4603 ERR("Failed to format snapshot name");
4604 ret_code = LTTNG_ERR_INVALID;
4605 goto error;
4606 }
4607 DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
4608 snapshot_output->name, session->name,
4609 snapshot_chunk_name);
4610 if (!session->kernel_session && !session->ust_session) {
4611 ERR("Failed to record snapshot as no channels exist");
4612 ret_code = LTTNG_ERR_NO_CHANNEL;
4613 goto error;
4614 }
4615
4616 if (session->kernel_session) {
4617 original_kernel_consumer_output =
4618 session->kernel_session->consumer;
4619 snapshot_kernel_consumer_output =
4620 consumer_copy_output(snapshot_output->consumer);
4621 strcpy(snapshot_kernel_consumer_output->chunk_path,
4622 snapshot_chunk_name);
4623 ret = consumer_copy_sockets(snapshot_kernel_consumer_output,
4624 original_kernel_consumer_output);
4625 if (ret < 0) {
4626 ERR("Failed to copy consumer sockets from snapshot output configuration");
4627 ret_code = LTTNG_ERR_NOMEM;
4628 goto error;
4629 }
4630 ret_code = set_relayd_for_snapshot(
4631 snapshot_kernel_consumer_output, session);
4632 if (ret_code != LTTNG_OK) {
4633 ERR("Failed to setup relay daemon for kernel tracer snapshot");
4634 goto error;
4635 }
4636 session->kernel_session->consumer =
4637 snapshot_kernel_consumer_output;
4638 }
4639 if (session->ust_session) {
4640 original_ust_consumer_output = session->ust_session->consumer;
4641 snapshot_ust_consumer_output =
4642 consumer_copy_output(snapshot_output->consumer);
4643 strcpy(snapshot_ust_consumer_output->chunk_path,
4644 snapshot_chunk_name);
4645 ret = consumer_copy_sockets(snapshot_ust_consumer_output,
4646 original_ust_consumer_output);
4647 if (ret < 0) {
4648 ERR("Failed to copy consumer sockets from snapshot output configuration");
4649 ret_code = LTTNG_ERR_NOMEM;
4650 goto error;
4651 }
4652 ret_code = set_relayd_for_snapshot(
4653 snapshot_ust_consumer_output, session);
4654 if (ret_code != LTTNG_OK) {
4655 ERR("Failed to setup relay daemon for userspace tracer snapshot");
4656 goto error;
4657 }
4658 session->ust_session->consumer =
4659 snapshot_ust_consumer_output;
4660 }
4661
4662 snapshot_trace_chunk = session_create_new_trace_chunk(session,
4663 snapshot_kernel_consumer_output ?:
4664 snapshot_ust_consumer_output,
4665 consumer_output_get_base_path(
4666 snapshot_output->consumer),
4667 snapshot_chunk_name);
4668 if (!snapshot_trace_chunk) {
4669 ERR("Failed to create temporary trace chunk to record a snapshot of session \"%s\"",
4670 session->name);
4671 ret_code = LTTNG_ERR_CREATE_DIR_FAIL;
4672 goto error;
4673 }
4674 assert(!session->current_trace_chunk);
4675 ret = session_set_trace_chunk(session, snapshot_trace_chunk, NULL);
4676 lttng_trace_chunk_put(snapshot_trace_chunk);
4677 snapshot_trace_chunk = NULL;
4678 if (ret) {
4679 ERR("Failed to set temporary trace chunk to record a snapshot of session \"%s\"",
4680 session->name);
4681 ret_code = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
4682 goto error;
4683 }
4684
4685 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
4686 snapshot_output->max_size);
4687 if (nb_packets_per_stream < 0) {
4688 ret_code = LTTNG_ERR_MAX_SIZE_INVALID;
4689 goto error;
4690 }
4691
4692 if (session->kernel_session) {
4693 ret_code = record_kernel_snapshot(session->kernel_session,
4694 snapshot_kernel_consumer_output, session,
4695 wait, nb_packets_per_stream);
4696 if (ret_code != LTTNG_OK) {
4697 goto error;
4698 }
4699 }
4700
4701 if (session->ust_session) {
4702 ret_code = record_ust_snapshot(session->ust_session,
4703 snapshot_ust_consumer_output, session,
4704 wait, nb_packets_per_stream);
4705 if (ret_code != LTTNG_OK) {
4706 goto error;
4707 }
4708 }
4709
4710 if (session_close_trace_chunk(
4711 session, session->current_trace_chunk, NULL, NULL)) {
4712 /*
4713 * Don't goto end; make sure the chunk is closed for the session
4714 * to allow future snapshots.
4715 */
4716 ERR("Failed to close snapshot trace chunk of session \"%s\"",
4717 session->name);
4718 ret_code = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
4719 }
4720 if (session_set_trace_chunk(session, NULL, NULL)) {
4721 ERR("Failed to release the current trace chunk of session \"%s\"",
4722 session->name);
4723 ret_code = LTTNG_ERR_UNK;
4724 }
4725 error:
4726 if (original_ust_consumer_output) {
4727 session->ust_session->consumer = original_ust_consumer_output;
4728 }
4729 if (original_kernel_consumer_output) {
4730 session->kernel_session->consumer =
4731 original_kernel_consumer_output;
4732 }
4733 consumer_output_put(snapshot_ust_consumer_output);
4734 consumer_output_put(snapshot_kernel_consumer_output);
4735 return ret_code;
4736 }
4737
4738 /*
4739 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
4740 *
4741 * The wait parameter is ignored so this call always wait for the snapshot to
4742 * complete before returning.
4743 *
4744 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4745 */
4746 int cmd_snapshot_record(struct ltt_session *session,
4747 const struct lttng_snapshot_output *output, int wait)
4748 {
4749 enum lttng_error_code cmd_ret = LTTNG_OK;
4750 int ret;
4751 unsigned int snapshot_success = 0;
4752 char datetime[16];
4753 struct snapshot_output *tmp_output = NULL;
4754
4755 assert(session);
4756 assert(output);
4757
4758 DBG("Cmd snapshot record for session %s", session->name);
4759
4760 /* Get the datetime for the snapshot output directory. */
4761 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
4762 sizeof(datetime));
4763 if (!ret) {
4764 cmd_ret = LTTNG_ERR_INVALID;
4765 goto error;
4766 }
4767
4768 /*
4769 * Permission denied to create an output if the session is not
4770 * set in no output mode.
4771 */
4772 if (session->output_traces) {
4773 cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4774 goto error;
4775 }
4776
4777 /* The session needs to be started at least once. */
4778 if (!session->has_been_started) {
4779 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4780 goto error;
4781 }
4782
4783 /* Use temporary output for the session. */
4784 if (*output->ctrl_url != '\0') {
4785 tmp_output = snapshot_output_alloc();
4786 if (!tmp_output) {
4787 cmd_ret = LTTNG_ERR_NOMEM;
4788 goto error;
4789 }
4790
4791 ret = snapshot_output_init(session, output->max_size,
4792 output->name,
4793 output->ctrl_url, output->data_url,
4794 session->consumer,
4795 tmp_output, NULL);
4796 if (ret < 0) {
4797 if (ret == -ENOMEM) {
4798 cmd_ret = LTTNG_ERR_NOMEM;
4799 } else {
4800 cmd_ret = LTTNG_ERR_INVALID;
4801 }
4802 goto error;
4803 }
4804 /* Use the global session count for the temporary snapshot. */
4805 tmp_output->nb_snapshot = session->snapshot.nb_snapshot;
4806
4807 /* Use the global datetime */
4808 memcpy(tmp_output->datetime, datetime, sizeof(datetime));
4809 cmd_ret = snapshot_record(session, tmp_output, wait);
4810 if (cmd_ret != LTTNG_OK) {
4811 goto error;
4812 }
4813 snapshot_success = 1;
4814 } else {
4815 struct snapshot_output *sout;
4816 struct lttng_ht_iter iter;
4817
4818 rcu_read_lock();
4819 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
4820 &iter.iter, sout, node.node) {
4821 struct snapshot_output output_copy;
4822
4823 /*
4824 * Make a local copy of the output and override output
4825 * parameters with those provided as part of the
4826 * command.
4827 */
4828 memcpy(&output_copy, sout, sizeof(output_copy));
4829
4830 if (output->max_size != (uint64_t) -1ULL) {
4831 output_copy.max_size = output->max_size;
4832 }
4833
4834 output_copy.nb_snapshot = session->snapshot.nb_snapshot;
4835 memcpy(output_copy.datetime, datetime,
4836 sizeof(datetime));
4837
4838 /* Use temporary name. */
4839 if (*output->name != '\0') {
4840 if (lttng_strncpy(output_copy.name,
4841 output->name,
4842 sizeof(output_copy.name))) {
4843 cmd_ret = LTTNG_ERR_INVALID;
4844 rcu_read_unlock();
4845 goto error;
4846 }
4847 }
4848
4849 cmd_ret = snapshot_record(session, &output_copy, wait);
4850 if (cmd_ret != LTTNG_OK) {
4851 rcu_read_unlock();
4852 goto error;
4853 }
4854 snapshot_success = 1;
4855 }
4856 rcu_read_unlock();
4857 }
4858
4859 if (snapshot_success) {
4860 session->snapshot.nb_snapshot++;
4861 } else {
4862 cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
4863 }
4864
4865 error:
4866 if (tmp_output) {
4867 snapshot_output_destroy(tmp_output);
4868 }
4869 return cmd_ret;
4870 }
4871
4872 /*
4873 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
4874 */
4875 int cmd_set_session_shm_path(struct ltt_session *session,
4876 const char *shm_path)
4877 {
4878 /* Safety net */
4879 assert(session);
4880
4881 /*
4882 * Can only set shm path before session is started.
4883 */
4884 if (session->has_been_started) {
4885 return LTTNG_ERR_SESSION_STARTED;
4886 }
4887
4888 strncpy(session->shm_path, shm_path,
4889 sizeof(session->shm_path));
4890 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
4891
4892 return 0;
4893 }
4894
4895 /*
4896 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
4897 *
4898 * Ask the consumer to rotate the session output directory.
4899 * The session lock must be held.
4900 *
4901 * Returns LTTNG_OK on success or else a negative LTTng error code.
4902 */
4903 int cmd_rotate_session(struct ltt_session *session,
4904 struct lttng_rotate_session_return *rotate_return,
4905 bool quiet_rotation)
4906 {
4907 int ret;
4908 uint64_t ongoing_rotation_chunk_id;
4909 enum lttng_error_code cmd_ret = LTTNG_OK;
4910 struct lttng_trace_chunk *chunk_being_archived = NULL;
4911 struct lttng_trace_chunk *new_trace_chunk = NULL;
4912 enum lttng_trace_chunk_status chunk_status;
4913 bool failed_to_rotate = false;
4914 enum lttng_error_code rotation_fail_code = LTTNG_OK;
4915
4916 assert(session);
4917
4918 if (!session->has_been_started) {
4919 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4920 goto end;
4921 }
4922
4923 /*
4924 * Explicit rotation is not supported for live sessions.
4925 * However, live sessions can perform a quiet rotation on
4926 * destroy.
4927 * Rotation is not supported for snapshot traces (no output).
4928 */
4929 if ((!quiet_rotation && session->live_timer) ||
4930 !session->output_traces) {
4931 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
4932 goto end;
4933 }
4934
4935 /* Unsupported feature in lttng-relayd before 2.11. */
4936 if (!quiet_rotation && session->consumer->type == CONSUMER_DST_NET &&
4937 (session->consumer->relay_major_version == 2 &&
4938 session->consumer->relay_minor_version < 11)) {
4939 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
4940 goto end;
4941 }
4942
4943 /* Unsupported feature in lttng-modules before 2.8 (lack of sequence number). */
4944 if (session->kernel_session && !kernel_supports_ring_buffer_packet_sequence_number()) {
4945 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL;
4946 goto end;
4947 }
4948
4949 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
4950 DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
4951 session->name);
4952 cmd_ret = LTTNG_ERR_ROTATION_PENDING;
4953 goto end;
4954 }
4955
4956 /*
4957 * After a stop, we only allow one rotation to occur, the other ones are
4958 * useless until a new start.
4959 */
4960 if (session->rotated_after_last_stop) {
4961 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
4962 session->name);
4963 cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
4964 goto end;
4965 }
4966 if (session->active) {
4967 new_trace_chunk = session_create_new_trace_chunk(session, NULL,
4968 NULL, NULL);
4969 if (!new_trace_chunk) {
4970 cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
4971 goto error;
4972 }
4973 }
4974
4975 /*
4976 * The current trace chunk becomes the chunk being archived.
4977 *
4978 * After this point, "chunk_being_archived" must absolutely
4979 * be closed on the consumer(s), otherwise it will never be
4980 * cleaned-up, which will result in a leak.
4981 */
4982 ret = session_set_trace_chunk(session, new_trace_chunk,
4983 &chunk_being_archived);
4984 if (ret) {
4985 cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
4986 goto error;
4987 }
4988
4989 if (session->kernel_session) {
4990 cmd_ret = kernel_rotate_session(session);
4991 if (cmd_ret != LTTNG_OK) {
4992 failed_to_rotate = true;
4993 rotation_fail_code = cmd_ret;
4994 }
4995 }
4996 if (session->ust_session) {
4997 cmd_ret = ust_app_rotate_session(session);
4998 if (cmd_ret != LTTNG_OK) {
4999 failed_to_rotate = true;
5000 rotation_fail_code = cmd_ret;
5001 }
5002 }
5003
5004 if (!session->active) {
5005 session->rotated_after_last_stop = true;
5006 }
5007
5008 if (!chunk_being_archived) {
5009 DBG("Rotating session \"%s\" from a \"NULL\" trace chunk to a new trace chunk, skipping completion check",
5010 session->name);
5011 if (failed_to_rotate) {
5012 cmd_ret = rotation_fail_code;
5013 goto error;
5014 }
5015 cmd_ret = LTTNG_OK;
5016 goto end;
5017 }
5018
5019 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
5020 chunk_status = lttng_trace_chunk_get_id(chunk_being_archived,
5021 &ongoing_rotation_chunk_id);
5022 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5023
5024 ret = session_close_trace_chunk(session, chunk_being_archived,
5025 quiet_rotation ?
5026 NULL :
5027 &((enum lttng_trace_chunk_command_type){
5028 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED}),
5029 session->last_chunk_path);
5030 if (ret) {
5031 cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5032 goto error;
5033 }
5034
5035 if (failed_to_rotate) {
5036 cmd_ret = rotation_fail_code;
5037 goto error;
5038 }
5039
5040 session->quiet_rotation = quiet_rotation;
5041 ret = timer_session_rotation_pending_check_start(session,
5042 DEFAULT_ROTATE_PENDING_TIMER);
5043 if (ret) {
5044 cmd_ret = LTTNG_ERR_UNK;
5045 goto error;
5046 }
5047
5048 if (rotate_return) {
5049 rotate_return->rotation_id = ongoing_rotation_chunk_id;
5050 }
5051
5052 session->chunk_being_archived = chunk_being_archived;
5053 chunk_being_archived = NULL;
5054 if (!quiet_rotation) {
5055 ret = notification_thread_command_session_rotation_ongoing(
5056 notification_thread_handle,
5057 session->name, session->uid, session->gid,
5058 ongoing_rotation_chunk_id);
5059 if (ret != LTTNG_OK) {
5060 ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
5061 session->name);
5062 cmd_ret = ret;
5063 }
5064 }
5065
5066 DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
5067 session->name, ongoing_rotation_chunk_id);
5068 end:
5069 lttng_trace_chunk_put(new_trace_chunk);
5070 lttng_trace_chunk_put(chunk_being_archived);
5071 ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
5072 return ret;
5073 error:
5074 if (session_reset_rotation_state(session,
5075 LTTNG_ROTATION_STATE_ERROR)) {
5076 ERR("Failed to reset rotation state of session \"%s\"",
5077 session->name);
5078 }
5079 goto end;
5080 }
5081
5082 /*
5083 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
5084 *
5085 * Check if the session has finished its rotation.
5086 *
5087 * Return LTTNG_OK on success or else an LTTNG_ERR code.
5088 */
5089 int cmd_rotate_get_info(struct ltt_session *session,
5090 struct lttng_rotation_get_info_return *info_return,
5091 uint64_t rotation_id)
5092 {
5093 enum lttng_error_code cmd_ret = LTTNG_OK;
5094 enum lttng_rotation_state rotation_state;
5095
5096 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
5097 session->most_recent_chunk_id.value);
5098
5099 if (session->chunk_being_archived) {
5100 enum lttng_trace_chunk_status chunk_status;
5101 uint64_t chunk_id;
5102
5103 chunk_status = lttng_trace_chunk_get_id(
5104 session->chunk_being_archived,
5105 &chunk_id);
5106 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5107
5108 rotation_state = rotation_id == chunk_id ?
5109 LTTNG_ROTATION_STATE_ONGOING :
5110 LTTNG_ROTATION_STATE_EXPIRED;
5111 } else {
5112 if (session->last_archived_chunk_id.is_set &&
5113 rotation_id != session->last_archived_chunk_id.value) {
5114 rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
5115 } else {
5116 rotation_state = session->rotation_state;
5117 }
5118 }
5119
5120 switch (rotation_state) {
5121 case LTTNG_ROTATION_STATE_NO_ROTATION:
5122 DBG("Reporting that no rotation has occurred within the lifetime of session \"%s\"",
5123 session->name);
5124 goto end;
5125 case LTTNG_ROTATION_STATE_EXPIRED:
5126 DBG("Reporting that the rotation state of rotation id %" PRIu64 " of session \"%s\" has expired",
5127 rotation_id, session->name);
5128 break;
5129 case LTTNG_ROTATION_STATE_ONGOING:
5130 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
5131 rotation_id, session->name);
5132 break;
5133 case LTTNG_ROTATION_STATE_COMPLETED:
5134 {
5135 int fmt_ret;
5136 char *chunk_path;
5137 char *current_tracing_path_reply;
5138 size_t current_tracing_path_reply_len;
5139
5140 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
5141 rotation_id, session->name);
5142
5143 switch (session_get_consumer_destination_type(session)) {
5144 case CONSUMER_DST_LOCAL:
5145 current_tracing_path_reply =
5146 info_return->location.local.absolute_path;
5147 current_tracing_path_reply_len =
5148 sizeof(info_return->location.local.absolute_path);
5149 info_return->location_type =
5150 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
5151 fmt_ret = asprintf(&chunk_path,
5152 "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
5153 session_get_base_path(session),
5154 session->last_archived_chunk_name);
5155 if (fmt_ret == -1) {
5156 PERROR("Failed to format the path of the last archived trace chunk");
5157 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5158 cmd_ret = LTTNG_ERR_UNK;
5159 goto end;
5160 }
5161 break;
5162 case CONSUMER_DST_NET:
5163 {
5164 uint16_t ctrl_port, data_port;
5165
5166 current_tracing_path_reply =
5167 info_return->location.relay.relative_path;
5168 current_tracing_path_reply_len =
5169 sizeof(info_return->location.relay.relative_path);
5170 /* Currently the only supported relay protocol. */
5171 info_return->location.relay.protocol =
5172 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
5173
5174 fmt_ret = lttng_strncpy(info_return->location.relay.host,
5175 session_get_net_consumer_hostname(session),
5176 sizeof(info_return->location.relay.host));
5177 if (fmt_ret) {
5178 ERR("Failed to copy host name to rotate_get_info reply");
5179 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5180 cmd_ret = LTTNG_ERR_SET_URL;
5181 goto end;
5182 }
5183
5184 session_get_net_consumer_ports(session, &ctrl_port, &data_port);
5185 info_return->location.relay.ports.control = ctrl_port;
5186 info_return->location.relay.ports.data = data_port;
5187 info_return->location_type =
5188 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
5189 chunk_path = strdup(session->last_chunk_path);
5190 if (!chunk_path) {
5191 ERR("Failed to allocate the path of the last archived trace chunk");
5192 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5193 cmd_ret = LTTNG_ERR_UNK;
5194 goto end;
5195 }
5196 break;
5197 }
5198 default:
5199 abort();
5200 }
5201
5202 fmt_ret = lttng_strncpy(current_tracing_path_reply,
5203 chunk_path, current_tracing_path_reply_len);
5204 free(chunk_path);
5205 if (fmt_ret) {
5206 ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
5207 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5208 cmd_ret = LTTNG_ERR_UNK;
5209 goto end;
5210 }
5211
5212 break;
5213 }
5214 case LTTNG_ROTATION_STATE_ERROR:
5215 DBG("Reporting that an error occurred during rotation %" PRIu64 " of session \"%s\"",
5216 rotation_id, session->name);
5217 break;
5218 default:
5219 abort();
5220 }
5221
5222 cmd_ret = LTTNG_OK;
5223 end:
5224 info_return->status = (int32_t) rotation_state;
5225 return cmd_ret;
5226 }
5227
5228 /*
5229 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
5230 *
5231 * Configure the automatic rotation parameters.
5232 * 'activate' to true means activate the rotation schedule type with 'new_value'.
5233 * 'activate' to false means deactivate the rotation schedule and validate that
5234 * 'new_value' has the same value as the currently active value.
5235 *
5236 * Return 0 on success or else a positive LTTNG_ERR code.
5237 */
5238 int cmd_rotation_set_schedule(struct ltt_session *session,
5239 bool activate, enum lttng_rotation_schedule_type schedule_type,
5240 uint64_t new_value,
5241 struct notification_thread_handle *notification_thread_handle)
5242 {
5243 int ret;
5244 uint64_t *parameter_value;
5245
5246 assert(session);
5247
5248 DBG("Cmd rotate set schedule session %s", session->name);
5249
5250 if (session->live_timer || !session->output_traces) {
5251 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
5252 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5253 goto end;
5254 }
5255
5256 switch (schedule_type) {
5257 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5258 parameter_value = &session->rotate_size;
5259 break;
5260 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5261 parameter_value = &session->rotate_timer_period;
5262 if (new_value >= UINT_MAX) {
5263 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
5264 new_value, UINT_MAX);
5265 ret = LTTNG_ERR_INVALID;
5266 goto end;
5267 }
5268 break;
5269 default:
5270 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
5271 ret = LTTNG_ERR_INVALID;
5272 goto end;
5273 }
5274
5275 /* Improper use of the API. */
5276 if (new_value == -1ULL) {
5277 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
5278 ret = LTTNG_ERR_INVALID;
5279 goto end;
5280 }
5281
5282 /*
5283 * As indicated in struct ltt_session's comments, a value of == 0 means
5284 * this schedule rotation type is not in use.
5285 *
5286 * Reject the command if we were asked to activate a schedule that was
5287 * already active.
5288 */
5289 if (activate && *parameter_value != 0) {
5290 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
5291 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
5292 goto end;
5293 }
5294
5295 /*
5296 * Reject the command if we were asked to deactivate a schedule that was
5297 * not active.
5298 */
5299 if (!activate && *parameter_value == 0) {
5300 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
5301 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5302 goto end;
5303 }
5304
5305 /*
5306 * Reject the command if we were asked to deactivate a schedule that
5307 * doesn't exist.
5308 */
5309 if (!activate && *parameter_value != new_value) {
5310 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
5311 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5312 goto end;
5313 }
5314
5315 *parameter_value = activate ? new_value : 0;
5316
5317 switch (schedule_type) {
5318 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5319 if (activate && session->active) {
5320 /*
5321 * Only start the timer if the session is active,
5322 * otherwise it will be started when the session starts.
5323 */
5324 ret = timer_session_rotation_schedule_timer_start(
5325 session, new_value);
5326 if (ret) {
5327 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
5328 ret = LTTNG_ERR_UNK;
5329 goto end;
5330 }
5331 } else {
5332 ret = timer_session_rotation_schedule_timer_stop(
5333 session);
5334 if (ret) {
5335 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
5336 ret = LTTNG_ERR_UNK;
5337 goto end;
5338 }
5339 }
5340 break;
5341 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5342 if (activate) {
5343 ret = subscribe_session_consumed_size_rotation(session,
5344 new_value, notification_thread_handle);
5345 if (ret) {
5346 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
5347 ret = LTTNG_ERR_UNK;
5348 goto end;
5349 }
5350 } else {
5351 ret = unsubscribe_session_consumed_size_rotation(session,
5352 notification_thread_handle);
5353 if (ret) {
5354 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
5355 ret = LTTNG_ERR_UNK;
5356 goto end;
5357 }
5358
5359 }
5360 break;
5361 default:
5362 /* Would have been caught before. */
5363 abort();
5364 }
5365
5366 ret = LTTNG_OK;
5367
5368 goto end;
5369
5370 end:
5371 return ret;
5372 }
5373
5374 /* Wait for a given path to be removed before continuing. */
5375 static enum lttng_error_code wait_on_path(void *path_data)
5376 {
5377 const char *shm_path = path_data;
5378
5379 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5380 shm_path);
5381 while (true) {
5382 int ret;
5383 struct stat st;
5384
5385 ret = stat(shm_path, &st);
5386 if (ret) {
5387 if (errno != ENOENT) {
5388 PERROR("stat() returned an error while checking for the existence of the shm path");
5389 } else {
5390 DBG("shm path no longer exists, completing the destruction of session");
5391 }
5392 break;
5393 } else {
5394 if (!S_ISDIR(st.st_mode)) {
5395 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5396 shm_path);
5397 break;
5398 }
5399 }
5400 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
5401 }
5402 return LTTNG_OK;
5403 }
5404
5405 /*
5406 * Returns a pointer to a handler to run on completion of a command.
5407 * Returns NULL if no handler has to be run for the last command executed.
5408 */
5409 const struct cmd_completion_handler *cmd_pop_completion_handler(void)
5410 {
5411 struct cmd_completion_handler *handler = current_completion_handler;
5412
5413 current_completion_handler = NULL;
5414 return handler;
5415 }
5416
5417 /*
5418 * Init command subsystem.
5419 */
5420 void cmd_init(void)
5421 {
5422 /*
5423 * Set network sequence index to 1 for streams to match a relayd
5424 * socket on the consumer side.
5425 */
5426 pthread_mutex_lock(&relayd_net_seq_idx_lock);
5427 relayd_net_seq_idx = 1;
5428 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
5429
5430 DBG("Command subsystem initialized");
5431 }
LTTng 2.0 tools and control repository
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