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[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 const bool session_cleared_after_last_stop =
2640 session->cleared_after_last_stop;
2641
2642 assert(session);
2643
2644 /* Ease our life a bit ;) */
2645 ksession = session->kernel_session;
2646 usess = session->ust_session;
2647
2648 /* Is the session already started? */
2649 if (session->active) {
2650 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2651 goto error;
2652 }
2653
2654 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING &&
2655 !session->current_trace_chunk) {
2656 /*
2657 * A rotation was launched while the session was stopped and
2658 * it has not been completed yet. It is not possible to start
2659 * the session since starting the session here would require a
2660 * rotation from "NULL" to a new trace chunk. That rotation
2661 * would overlap with the ongoing rotation, which is not
2662 * supported.
2663 */
2664 WARN("Refusing to start session \"%s\" as a rotation launched after the last \"stop\" is still ongoing",
2665 session->name);
2666 ret = LTTNG_ERR_ROTATION_PENDING;
2667 goto error;
2668 }
2669
2670 /*
2671 * Starting a session without channel is useless since after that it's not
2672 * possible to enable channel thus inform the client.
2673 */
2674 if (usess && usess->domain_global.channels) {
2675 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2676 }
2677 if (ksession) {
2678 nb_chan += ksession->channel_count;
2679 }
2680 if (!nb_chan) {
2681 ret = LTTNG_ERR_NO_CHANNEL;
2682 goto error;
2683 }
2684
2685 session->active = 1;
2686 session->rotated_after_last_stop = false;
2687 session->cleared_after_last_stop = false;
2688 if (session->output_traces && !session->current_trace_chunk) {
2689 if (!session->has_been_started) {
2690 struct lttng_trace_chunk *trace_chunk;
2691
2692 DBG("Creating initial trace chunk of session \"%s\"",
2693 session->name);
2694 trace_chunk = session_create_new_trace_chunk(
2695 session, NULL, NULL, NULL);
2696 if (!trace_chunk) {
2697 ret = LTTNG_ERR_CREATE_DIR_FAIL;
2698 goto error;
2699 }
2700 assert(!session->current_trace_chunk);
2701 ret = session_set_trace_chunk(session, trace_chunk,
2702 NULL);
2703 lttng_trace_chunk_put(trace_chunk);
2704 if (ret) {
2705 ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
2706 goto error;
2707 }
2708 } else {
2709 DBG("Rotating session \"%s\" from its current \"NULL\" trace chunk to a new chunk",
2710 session->name);
2711 /*
2712 * Rotate existing streams into the new chunk.
2713 * This is a "quiet" rotation has no client has
2714 * explicitly requested this operation.
2715 *
2716 * There is also no need to wait for the rotation
2717 * to complete as it will happen immediately. No data
2718 * was produced as the session was stopped, so the
2719 * rotation should happen on reception of the command.
2720 */
2721 ret = cmd_rotate_session(session, NULL, true,
2722 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
2723 if (ret != LTTNG_OK) {
2724 goto error;
2725 }
2726 }
2727 }
2728
2729 /* Kernel tracing */
2730 if (ksession != NULL) {
2731 DBG("Start kernel tracing session %s", session->name);
2732 ret = start_kernel_session(ksession);
2733 if (ret != LTTNG_OK) {
2734 goto error;
2735 }
2736 }
2737
2738 /* Flag session that trace should start automatically */
2739 if (usess) {
2740 int int_ret = ust_app_start_trace_all(usess);
2741
2742 if (int_ret < 0) {
2743 ret = LTTNG_ERR_UST_START_FAIL;
2744 goto error;
2745 }
2746 }
2747
2748 /*
2749 * Clear the flag that indicates that a rotation was done while the
2750 * session was stopped.
2751 */
2752 session->rotated_after_last_stop = false;
2753
2754 if (session->rotate_timer_period) {
2755 int int_ret = timer_session_rotation_schedule_timer_start(
2756 session, session->rotate_timer_period);
2757
2758 if (int_ret < 0) {
2759 ERR("Failed to enable rotate timer");
2760 ret = LTTNG_ERR_UNK;
2761 goto error;
2762 }
2763 }
2764
2765 ret = LTTNG_OK;
2766
2767 error:
2768 if (ret == LTTNG_OK) {
2769 /* Flag this after a successful start. */
2770 session->has_been_started |= 1;
2771 } else {
2772 session->active = 0;
2773 /* Restore initial state on error. */
2774 session->rotated_after_last_stop =
2775 session_rotated_after_last_stop;
2776 session->cleared_after_last_stop =
2777 session_cleared_after_last_stop;
2778 }
2779 return ret;
2780 }
2781
2782 /*
2783 * Command LTTNG_STOP_TRACE processed by the client thread.
2784 */
2785 int cmd_stop_trace(struct ltt_session *session)
2786 {
2787 int ret;
2788 struct ltt_kernel_session *ksession;
2789 struct ltt_ust_session *usess;
2790
2791 assert(session);
2792
2793 DBG("Begin stop session \"%s\" (id %" PRIu64 ")", session->name, session->id);
2794 /* Short cut */
2795 ksession = session->kernel_session;
2796 usess = session->ust_session;
2797
2798 /* Session is not active. Skip everythong and inform the client. */
2799 if (!session->active) {
2800 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2801 goto error;
2802 }
2803
2804 ret = stop_kernel_session(ksession);
2805 if (ret != LTTNG_OK) {
2806 goto error;
2807 }
2808
2809 if (usess && usess->active) {
2810 ret = ust_app_stop_trace_all(usess);
2811 if (ret < 0) {
2812 ret = LTTNG_ERR_UST_STOP_FAIL;
2813 goto error;
2814 }
2815 }
2816
2817 DBG("Completed stop session \"%s\" (id %" PRIu64 ")", session->name,
2818 session->id);
2819 /* Flag inactive after a successful stop. */
2820 session->active = 0;
2821 ret = LTTNG_OK;
2822
2823 error:
2824 return ret;
2825 }
2826
2827 /*
2828 * Set the base_path of the session only if subdir of a control uris is set.
2829 * Return LTTNG_OK on success, otherwise LTTNG_ERR_*.
2830 */
2831 static int set_session_base_path_from_uris(struct ltt_session *session,
2832 size_t nb_uri,
2833 struct lttng_uri *uris)
2834 {
2835 int ret;
2836 size_t i;
2837
2838 for (i = 0; i < nb_uri; i++) {
2839 if (uris[i].stype != LTTNG_STREAM_CONTROL ||
2840 uris[i].subdir[0] == '\0') {
2841 /* Not interested in these URIs */
2842 continue;
2843 }
2844
2845 if (session->base_path != NULL) {
2846 free(session->base_path);
2847 session->base_path = NULL;
2848 }
2849
2850 /* Set session base_path */
2851 session->base_path = strdup(uris[i].subdir);
2852 if (!session->base_path) {
2853 PERROR("Failed to copy base path \"%s\" to session \"%s\"",
2854 uris[i].subdir, session->name);
2855 ret = LTTNG_ERR_NOMEM;
2856 goto error;
2857 }
2858 DBG2("Setting base path \"%s\" for session \"%s\"",
2859 session->base_path, session->name);
2860 }
2861 ret = LTTNG_OK;
2862 error:
2863 return ret;
2864 }
2865
2866 /*
2867 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2868 */
2869 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2870 struct lttng_uri *uris)
2871 {
2872 int ret, i;
2873 struct ltt_kernel_session *ksess = session->kernel_session;
2874 struct ltt_ust_session *usess = session->ust_session;
2875
2876 assert(session);
2877 assert(uris);
2878 assert(nb_uri > 0);
2879
2880 /* Can't set consumer URI if the session is active. */
2881 if (session->active) {
2882 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2883 goto error;
2884 }
2885
2886 /*
2887 * Set the session base path if any. This is done inside
2888 * cmd_set_consumer_uri to preserve backward compatibility of the
2889 * previous session creation api vs the session descriptor api.
2890 */
2891 ret = set_session_base_path_from_uris(session, nb_uri, uris);
2892 if (ret != LTTNG_OK) {
2893 goto error;
2894 }
2895
2896 /* Set the "global" consumer URIs */
2897 for (i = 0; i < nb_uri; i++) {
2898 ret = add_uri_to_consumer(session, session->consumer, &uris[i],
2899 LTTNG_DOMAIN_NONE);
2900 if (ret != LTTNG_OK) {
2901 goto error;
2902 }
2903 }
2904
2905 /* Set UST session URIs */
2906 if (session->ust_session) {
2907 for (i = 0; i < nb_uri; i++) {
2908 ret = add_uri_to_consumer(session,
2909 session->ust_session->consumer,
2910 &uris[i], LTTNG_DOMAIN_UST);
2911 if (ret != LTTNG_OK) {
2912 goto error;
2913 }
2914 }
2915 }
2916
2917 /* Set kernel session URIs */
2918 if (session->kernel_session) {
2919 for (i = 0; i < nb_uri; i++) {
2920 ret = add_uri_to_consumer(session,
2921 session->kernel_session->consumer,
2922 &uris[i], LTTNG_DOMAIN_KERNEL);
2923 if (ret != LTTNG_OK) {
2924 goto error;
2925 }
2926 }
2927 }
2928
2929 /*
2930 * Make sure to set the session in output mode after we set URI since a
2931 * session can be created without URL (thus flagged in no output mode).
2932 */
2933 session->output_traces = 1;
2934 if (ksess) {
2935 ksess->output_traces = 1;
2936 }
2937
2938 if (usess) {
2939 usess->output_traces = 1;
2940 }
2941
2942 /* All good! */
2943 ret = LTTNG_OK;
2944
2945 error:
2946 return ret;
2947 }
2948
2949 static
2950 enum lttng_error_code set_session_output_from_descriptor(
2951 struct ltt_session *session,
2952 const struct lttng_session_descriptor *descriptor)
2953 {
2954 int ret;
2955 enum lttng_error_code ret_code = LTTNG_OK;
2956 enum lttng_session_descriptor_type session_type =
2957 lttng_session_descriptor_get_type(descriptor);
2958 enum lttng_session_descriptor_output_type output_type =
2959 lttng_session_descriptor_get_output_type(descriptor);
2960 struct lttng_uri uris[2] = {};
2961 size_t uri_count = 0;
2962
2963 switch (output_type) {
2964 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NONE:
2965 goto end;
2966 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_LOCAL:
2967 lttng_session_descriptor_get_local_output_uri(descriptor,
2968 &uris[0]);
2969 uri_count = 1;
2970 break;
2971 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NETWORK:
2972 lttng_session_descriptor_get_network_output_uris(descriptor,
2973 &uris[0], &uris[1]);
2974 uri_count = 2;
2975 break;
2976 default:
2977 ret_code = LTTNG_ERR_INVALID;
2978 goto end;
2979 }
2980
2981 switch (session_type) {
2982 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
2983 {
2984 struct snapshot_output *new_output = NULL;
2985
2986 new_output = snapshot_output_alloc();
2987 if (!new_output) {
2988 ret_code = LTTNG_ERR_NOMEM;
2989 goto end;
2990 }
2991
2992 ret = snapshot_output_init_with_uri(session,
2993 DEFAULT_SNAPSHOT_MAX_SIZE,
2994 NULL, uris, uri_count, session->consumer,
2995 new_output, &session->snapshot);
2996 if (ret < 0) {
2997 ret_code = (ret == -ENOMEM) ?
2998 LTTNG_ERR_NOMEM : LTTNG_ERR_INVALID;
2999 snapshot_output_destroy(new_output);
3000 goto end;
3001 }
3002 snapshot_add_output(&session->snapshot, new_output);
3003 break;
3004 }
3005 case LTTNG_SESSION_DESCRIPTOR_TYPE_REGULAR:
3006 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3007 {
3008 ret_code = cmd_set_consumer_uri(session, uri_count, uris);
3009 break;
3010 }
3011 default:
3012 ret_code = LTTNG_ERR_INVALID;
3013 goto end;
3014 }
3015 end:
3016 return ret_code;
3017 }
3018
3019 static
3020 enum lttng_error_code cmd_create_session_from_descriptor(
3021 struct lttng_session_descriptor *descriptor,
3022 const lttng_sock_cred *creds,
3023 const char *home_path)
3024 {
3025 int ret;
3026 enum lttng_error_code ret_code;
3027 const char *session_name;
3028 struct ltt_session *new_session = NULL;
3029 enum lttng_session_descriptor_status descriptor_status;
3030
3031 session_lock_list();
3032 if (home_path) {
3033 if (*home_path != '/') {
3034 ERR("Home path provided by client is not absolute");
3035 ret_code = LTTNG_ERR_INVALID;
3036 goto end;
3037 }
3038 }
3039
3040 descriptor_status = lttng_session_descriptor_get_session_name(
3041 descriptor, &session_name);
3042 switch (descriptor_status) {
3043 case LTTNG_SESSION_DESCRIPTOR_STATUS_OK:
3044 break;
3045 case LTTNG_SESSION_DESCRIPTOR_STATUS_UNSET:
3046 session_name = NULL;
3047 break;
3048 default:
3049 ret_code = LTTNG_ERR_INVALID;
3050 goto end;
3051 }
3052
3053 ret_code = session_create(session_name, creds->uid, creds->gid,
3054 &new_session);
3055 if (ret_code != LTTNG_OK) {
3056 goto end;
3057 }
3058
3059 if (!session_name) {
3060 ret = lttng_session_descriptor_set_session_name(descriptor,
3061 new_session->name);
3062 if (ret) {
3063 ret_code = LTTNG_ERR_SESSION_FAIL;
3064 goto end;
3065 }
3066 }
3067
3068 if (!lttng_session_descriptor_is_output_destination_initialized(
3069 descriptor)) {
3070 /*
3071 * Only include the session's creation time in the output
3072 * destination if the name of the session itself was
3073 * not auto-generated.
3074 */
3075 ret_code = lttng_session_descriptor_set_default_output(
3076 descriptor,
3077 session_name ? &new_session->creation_time : NULL,
3078 home_path);
3079 if (ret_code != LTTNG_OK) {
3080 goto end;
3081 }
3082 } else {
3083 new_session->has_user_specified_directory =
3084 lttng_session_descriptor_has_output_directory(
3085 descriptor);
3086 }
3087
3088 switch (lttng_session_descriptor_get_type(descriptor)) {
3089 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
3090 new_session->snapshot_mode = 1;
3091 break;
3092 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3093 new_session->live_timer =
3094 lttng_session_descriptor_live_get_timer_interval(
3095 descriptor);
3096 break;
3097 default:
3098 break;
3099 }
3100
3101 ret_code = set_session_output_from_descriptor(new_session, descriptor);
3102 if (ret_code != LTTNG_OK) {
3103 goto end;
3104 }
3105 new_session->consumer->enabled = 1;
3106 ret_code = LTTNG_OK;
3107 end:
3108 /* Release reference provided by the session_create function. */
3109 session_put(new_session);
3110 if (ret_code != LTTNG_OK && new_session) {
3111 /* Release the global reference on error. */
3112 session_destroy(new_session);
3113 }
3114 session_unlock_list();
3115 return ret_code;
3116 }
3117
3118 enum lttng_error_code cmd_create_session(struct command_ctx *cmd_ctx, int sock,
3119 struct lttng_session_descriptor **return_descriptor)
3120 {
3121 int ret;
3122 size_t payload_size;
3123 struct lttng_dynamic_buffer payload;
3124 struct lttng_buffer_view home_dir_view;
3125 struct lttng_buffer_view session_descriptor_view;
3126 struct lttng_session_descriptor *session_descriptor = NULL;
3127 enum lttng_error_code ret_code;
3128
3129 lttng_dynamic_buffer_init(&payload);
3130 if (cmd_ctx->lsm->u.create_session.home_dir_size >=
3131 LTTNG_PATH_MAX) {
3132 ret_code = LTTNG_ERR_INVALID;
3133 goto error;
3134 }
3135 if (cmd_ctx->lsm->u.create_session.session_descriptor_size >
3136 LTTNG_SESSION_DESCRIPTOR_MAX_LEN) {
3137 ret_code = LTTNG_ERR_INVALID;
3138 goto error;
3139 }
3140
3141 payload_size = cmd_ctx->lsm->u.create_session.home_dir_size +
3142 cmd_ctx->lsm->u.create_session.session_descriptor_size;
3143 ret = lttng_dynamic_buffer_set_size(&payload, payload_size);
3144 if (ret) {
3145 ret_code = LTTNG_ERR_NOMEM;
3146 goto error;
3147 }
3148
3149 ret = lttcomm_recv_unix_sock(sock, payload.data, payload.size);
3150 if (ret <= 0) {
3151 ERR("Reception of session descriptor failed, aborting.");
3152 ret_code = LTTNG_ERR_SESSION_FAIL;
3153 goto error;
3154 }
3155
3156 home_dir_view = lttng_buffer_view_from_dynamic_buffer(
3157 &payload,
3158 0,
3159 cmd_ctx->lsm->u.create_session.home_dir_size);
3160 session_descriptor_view = lttng_buffer_view_from_dynamic_buffer(
3161 &payload,
3162 cmd_ctx->lsm->u.create_session.home_dir_size,
3163 cmd_ctx->lsm->u.create_session.session_descriptor_size);
3164
3165 ret = lttng_session_descriptor_create_from_buffer(
3166 &session_descriptor_view, &session_descriptor);
3167 if (ret < 0) {
3168 ERR("Failed to create session descriptor from payload of \"create session\" command");
3169 ret_code = LTTNG_ERR_INVALID;
3170 goto error;
3171 }
3172
3173 /*
3174 * Sets the descriptor's auto-generated properties (name, output) if
3175 * needed.
3176 */
3177 ret_code = cmd_create_session_from_descriptor(session_descriptor,
3178 &cmd_ctx->creds,
3179 home_dir_view.size ? home_dir_view.data : NULL);
3180 if (ret_code != LTTNG_OK) {
3181 goto error;
3182 }
3183
3184 ret_code = LTTNG_OK;
3185 *return_descriptor = session_descriptor;
3186 session_descriptor = NULL;
3187 error:
3188 lttng_dynamic_buffer_reset(&payload);
3189 lttng_session_descriptor_destroy(session_descriptor);
3190 return ret_code;
3191 }
3192
3193 static
3194 void cmd_destroy_session_reply(const struct ltt_session *session,
3195 void *_reply_context)
3196 {
3197 int ret;
3198 ssize_t comm_ret;
3199 const struct cmd_destroy_session_reply_context *reply_context =
3200 _reply_context;
3201 struct lttng_dynamic_buffer payload;
3202 struct lttcomm_session_destroy_command_header cmd_header;
3203 struct lttng_trace_archive_location *location = NULL;
3204 struct lttcomm_lttng_msg llm = {
3205 .cmd_type = LTTNG_DESTROY_SESSION,
3206 .ret_code = reply_context->destruction_status,
3207 .pid = UINT32_MAX,
3208 .cmd_header_size =
3209 sizeof(struct lttcomm_session_destroy_command_header),
3210 .data_size = 0,
3211 };
3212 size_t payload_size_before_location;
3213
3214 lttng_dynamic_buffer_init(&payload);
3215
3216 ret = lttng_dynamic_buffer_append(&payload, &llm, sizeof(llm));
3217 if (ret) {
3218 ERR("Failed to append session destruction message");
3219 goto error;
3220 }
3221
3222 cmd_header.rotation_state =
3223 (int32_t) (reply_context->implicit_rotation_on_destroy ?
3224 session->rotation_state :
3225 LTTNG_ROTATION_STATE_NO_ROTATION);
3226 ret = lttng_dynamic_buffer_append(&payload, &cmd_header,
3227 sizeof(cmd_header));
3228 if (ret) {
3229 ERR("Failed to append session destruction command header");
3230 goto error;
3231 }
3232
3233 if (!reply_context->implicit_rotation_on_destroy) {
3234 DBG("No implicit rotation performed during the destruction of session \"%s\", sending reply",
3235 session->name);
3236 goto send_reply;
3237 }
3238 if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED) {
3239 DBG("Rotation state of session \"%s\" is not \"completed\", sending session destruction reply",
3240 session->name);
3241 goto send_reply;
3242 }
3243
3244 location = session_get_trace_archive_location(session);
3245 if (!location) {
3246 ERR("Failed to get the location of the trace archive produced during the destruction of session \"%s\"",
3247 session->name);
3248 goto error;
3249 }
3250
3251 payload_size_before_location = payload.size;
3252 comm_ret = lttng_trace_archive_location_serialize(location,
3253 &payload);
3254 if (comm_ret < 0) {
3255 ERR("Failed to serialize the location of the trace archive produced during the destruction of session \"%s\"",
3256 session->name);
3257 goto error;
3258 }
3259 /* Update the message to indicate the location's length. */
3260 ((struct lttcomm_lttng_msg *) payload.data)->data_size =
3261 payload.size - payload_size_before_location;
3262 send_reply:
3263 comm_ret = lttcomm_send_unix_sock(reply_context->reply_sock_fd,
3264 payload.data, payload.size);
3265 if (comm_ret != (ssize_t) payload.size) {
3266 ERR("Failed to send result of the destruction of session \"%s\" to client",
3267 session->name);
3268 }
3269 error:
3270 ret = close(reply_context->reply_sock_fd);
3271 if (ret) {
3272 PERROR("Failed to close client socket in deferred session destroy reply");
3273 }
3274 lttng_dynamic_buffer_reset(&payload);
3275 free(_reply_context);
3276 }
3277
3278 /*
3279 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3280 *
3281 * Called with session lock held.
3282 */
3283 int cmd_destroy_session(struct ltt_session *session,
3284 struct notification_thread_handle *notification_thread_handle,
3285 int *sock_fd)
3286 {
3287 int ret;
3288 enum lttng_error_code destruction_last_error = LTTNG_OK;
3289 struct cmd_destroy_session_reply_context *reply_context = NULL;
3290
3291 if (sock_fd) {
3292 reply_context = zmalloc(sizeof(*reply_context));
3293 if (!reply_context) {
3294 ret = LTTNG_ERR_NOMEM;
3295 goto end;
3296 }
3297 reply_context->reply_sock_fd = *sock_fd;
3298 }
3299
3300 /* Safety net */
3301 assert(session);
3302
3303 DBG("Begin destroy session %s (id %" PRIu64 ")", session->name,
3304 session->id);
3305 if (session->active) {
3306 DBG("Session \"%s\" is active, attempting to stop it before destroying it",
3307 session->name);
3308 ret = cmd_stop_trace(session);
3309 if (ret != LTTNG_OK && ret != LTTNG_ERR_TRACE_ALREADY_STOPPED) {
3310 /* Carry on with the destruction of the session. */
3311 ERR("Failed to stop session \"%s\" as part of its destruction: %s",
3312 session->name, lttng_strerror(-ret));
3313 destruction_last_error = ret;
3314 }
3315 }
3316
3317 if (session->rotation_schedule_timer_enabled) {
3318 if (timer_session_rotation_schedule_timer_stop(
3319 session)) {
3320 ERR("Failed to stop the \"rotation schedule\" timer of session %s",
3321 session->name);
3322 destruction_last_error = LTTNG_ERR_TIMER_STOP_ERROR;
3323 }
3324 }
3325
3326 if (session->rotate_size) {
3327 unsubscribe_session_consumed_size_rotation(session, notification_thread_handle);
3328 session->rotate_size = 0;
3329 }
3330
3331 if (session->rotated && session->current_trace_chunk && session->output_traces) {
3332 /*
3333 * Perform a last rotation on destruction if rotations have
3334 * occurred during the session's lifetime.
3335 */
3336 ret = cmd_rotate_session(session, NULL, false,
3337 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
3338 if (ret != LTTNG_OK) {
3339 ERR("Failed to perform an implicit rotation as part of the destruction of session \"%s\": %s",
3340 session->name, lttng_strerror(-ret));
3341 destruction_last_error = -ret;
3342 }
3343 if (reply_context) {
3344 reply_context->implicit_rotation_on_destroy = true;
3345 }
3346 } else if (session->has_been_started && session->current_trace_chunk) {
3347 /*
3348 * The user has not triggered a session rotation. However, to
3349 * ensure all data has been consumed, the session is rotated
3350 * to a 'null' trace chunk before it is destroyed.
3351 *
3352 * This is a "quiet" rotation meaning that no notification is
3353 * emitted and no renaming of the current trace chunk takes
3354 * place.
3355 */
3356 ret = cmd_rotate_session(session, NULL, true,
3357 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
3358 if (ret != LTTNG_OK) {
3359 ERR("Failed to perform a quiet rotation as part of the destruction of session \"%s\": %s",
3360 session->name, lttng_strerror(-ret));
3361 destruction_last_error = -ret;
3362 }
3363 }
3364
3365 if (session->shm_path[0]) {
3366 /*
3367 * When a session is created with an explicit shm_path,
3368 * the consumer daemon will create its shared memory files
3369 * at that location and will *not* unlink them. This is normal
3370 * as the intention of that feature is to make it possible
3371 * to retrieve the content of those files should a crash occur.
3372 *
3373 * To ensure the content of those files can be used, the
3374 * sessiond daemon will replicate the content of the metadata
3375 * cache in a metadata file.
3376 *
3377 * On clean-up, it is expected that the consumer daemon will
3378 * unlink the shared memory files and that the session daemon
3379 * will unlink the metadata file. Then, the session's directory
3380 * in the shm path can be removed.
3381 *
3382 * Unfortunately, a flaw in the design of the sessiond's and
3383 * consumerd's tear down of channels makes it impossible to
3384 * determine when the sessiond _and_ the consumerd have both
3385 * destroyed their representation of a channel. For one, the
3386 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3387 * callbacks in both daemons.
3388 *
3389 * However, it is also impossible for the sessiond to know when
3390 * the consumer daemon is done destroying its channel(s) since
3391 * it occurs as a reaction to the closing of the channel's file
3392 * descriptor. There is no resulting communication initiated
3393 * from the consumerd to the sessiond to confirm that the
3394 * operation is completed (and was successful).
3395 *
3396 * Until this is all fixed, the session daemon checks for the
3397 * removal of the session's shm path which makes it possible
3398 * to safely advertise a session as having been destroyed.
3399 *
3400 * Prior to this fix, it was not possible to reliably save
3401 * a session making use of the --shm-path option, destroy it,
3402 * and load it again. This is because the creation of the
3403 * session would fail upon seeing the session's shm path
3404 * already in existence.
3405 *
3406 * Note that none of the error paths in the check for the
3407 * directory's existence return an error. This is normal
3408 * as there isn't much that can be done. The session will
3409 * be destroyed properly, except that we can't offer the
3410 * guarantee that the same session can be re-created.
3411 */
3412 current_completion_handler = &destroy_completion_handler.handler;
3413 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3414 session->shm_path,
3415 sizeof(destroy_completion_handler.shm_path));
3416 assert(!ret);
3417 }
3418
3419 /*
3420 * The session is destroyed. However, note that the command context
3421 * still holds a reference to the session, thus delaying its destruction
3422 * _at least_ up to the point when that reference is released.
3423 */
3424 session_destroy(session);
3425 if (reply_context) {
3426 reply_context->destruction_status = destruction_last_error;
3427 ret = session_add_destroy_notifier(session,
3428 cmd_destroy_session_reply,
3429 (void *) reply_context);
3430 if (ret) {
3431 ret = LTTNG_ERR_FATAL;
3432 goto end;
3433 } else {
3434 *sock_fd = -1;
3435 }
3436 }
3437 ret = LTTNG_OK;
3438 end:
3439 return ret;
3440 }
3441
3442 /*
3443 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3444 */
3445 int cmd_register_consumer(struct ltt_session *session,
3446 enum lttng_domain_type domain, const char *sock_path,
3447 struct consumer_data *cdata)
3448 {
3449 int ret, sock;
3450 struct consumer_socket *socket = NULL;
3451
3452 assert(session);
3453 assert(cdata);
3454 assert(sock_path);
3455
3456 switch (domain) {
3457 case LTTNG_DOMAIN_KERNEL:
3458 {
3459 struct ltt_kernel_session *ksess = session->kernel_session;
3460
3461 assert(ksess);
3462
3463 /* Can't register a consumer if there is already one */
3464 if (ksess->consumer_fds_sent != 0) {
3465 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3466 goto error;
3467 }
3468
3469 sock = lttcomm_connect_unix_sock(sock_path);
3470 if (sock < 0) {
3471 ret = LTTNG_ERR_CONNECT_FAIL;
3472 goto error;
3473 }
3474 cdata->cmd_sock = sock;
3475
3476 socket = consumer_allocate_socket(&cdata->cmd_sock);
3477 if (socket == NULL) {
3478 ret = close(sock);
3479 if (ret < 0) {
3480 PERROR("close register consumer");
3481 }
3482 cdata->cmd_sock = -1;
3483 ret = LTTNG_ERR_FATAL;
3484 goto error;
3485 }
3486
3487 socket->lock = zmalloc(sizeof(pthread_mutex_t));
3488 if (socket->lock == NULL) {
3489 PERROR("zmalloc pthread mutex");
3490 ret = LTTNG_ERR_FATAL;
3491 goto error;
3492 }
3493 pthread_mutex_init(socket->lock, NULL);
3494 socket->registered = 1;
3495
3496 rcu_read_lock();
3497 consumer_add_socket(socket, ksess->consumer);
3498 rcu_read_unlock();
3499
3500 pthread_mutex_lock(&cdata->pid_mutex);
3501 cdata->pid = -1;
3502 pthread_mutex_unlock(&cdata->pid_mutex);
3503
3504 break;
3505 }
3506 default:
3507 /* TODO: Userspace tracing */
3508 ret = LTTNG_ERR_UND;
3509 goto error;
3510 }
3511
3512 return LTTNG_OK;
3513
3514 error:
3515 if (socket) {
3516 consumer_destroy_socket(socket);
3517 }
3518 return ret;
3519 }
3520
3521 /*
3522 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3523 */
3524 ssize_t cmd_list_domains(struct ltt_session *session,
3525 struct lttng_domain **domains)
3526 {
3527 int ret, index = 0;
3528 ssize_t nb_dom = 0;
3529 struct agent *agt;
3530 struct lttng_ht_iter iter;
3531
3532 if (session->kernel_session != NULL) {
3533 DBG3("Listing domains found kernel domain");
3534 nb_dom++;
3535 }
3536
3537 if (session->ust_session != NULL) {
3538 DBG3("Listing domains found UST global domain");
3539 nb_dom++;
3540
3541 rcu_read_lock();
3542 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3543 agt, node.node) {
3544 if (agt->being_used) {
3545 nb_dom++;
3546 }
3547 }
3548 rcu_read_unlock();
3549 }
3550
3551 if (!nb_dom) {
3552 goto end;
3553 }
3554
3555 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3556 if (*domains == NULL) {
3557 ret = LTTNG_ERR_FATAL;
3558 goto error;
3559 }
3560
3561 if (session->kernel_session != NULL) {
3562 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3563
3564 /* Kernel session buffer type is always GLOBAL */
3565 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3566
3567 index++;
3568 }
3569
3570 if (session->ust_session != NULL) {
3571 (*domains)[index].type = LTTNG_DOMAIN_UST;
3572 (*domains)[index].buf_type = session->ust_session->buffer_type;
3573 index++;
3574
3575 rcu_read_lock();
3576 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3577 agt, node.node) {
3578 if (agt->being_used) {
3579 (*domains)[index].type = agt->domain;
3580 (*domains)[index].buf_type = session->ust_session->buffer_type;
3581 index++;
3582 }
3583 }
3584 rcu_read_unlock();
3585 }
3586 end:
3587 return nb_dom;
3588
3589 error:
3590 /* Return negative value to differentiate return code */
3591 return -ret;
3592 }
3593
3594
3595 /*
3596 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3597 */
3598 ssize_t cmd_list_channels(enum lttng_domain_type domain,
3599 struct ltt_session *session, struct lttng_channel **channels)
3600 {
3601 ssize_t nb_chan = 0, payload_size = 0, ret;
3602
3603 switch (domain) {
3604 case LTTNG_DOMAIN_KERNEL:
3605 if (session->kernel_session != NULL) {
3606 nb_chan = session->kernel_session->channel_count;
3607 }
3608 DBG3("Number of kernel channels %zd", nb_chan);
3609 if (nb_chan <= 0) {
3610 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
3611 goto end;
3612 }
3613 break;
3614 case LTTNG_DOMAIN_UST:
3615 if (session->ust_session != NULL) {
3616 rcu_read_lock();
3617 nb_chan = lttng_ht_get_count(
3618 session->ust_session->domain_global.channels);
3619 rcu_read_unlock();
3620 }
3621 DBG3("Number of UST global channels %zd", nb_chan);
3622 if (nb_chan < 0) {
3623 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
3624 goto end;
3625 }
3626 break;
3627 default:
3628 ret = -LTTNG_ERR_UND;
3629 goto end;
3630 }
3631
3632 if (nb_chan > 0) {
3633 const size_t channel_size = sizeof(struct lttng_channel) +
3634 sizeof(struct lttng_channel_extended);
3635 struct lttng_channel_extended *channel_exts;
3636
3637 payload_size = nb_chan * channel_size;
3638 *channels = zmalloc(payload_size);
3639 if (*channels == NULL) {
3640 ret = -LTTNG_ERR_FATAL;
3641 goto end;
3642 }
3643
3644 channel_exts = ((void *) *channels) +
3645 (nb_chan * sizeof(struct lttng_channel));
3646 ret = list_lttng_channels(domain, session, *channels, channel_exts);
3647 if (ret != LTTNG_OK) {
3648 free(*channels);
3649 *channels = NULL;
3650 goto end;
3651 }
3652 } else {
3653 *channels = NULL;
3654 }
3655
3656 ret = payload_size;
3657 end:
3658 return ret;
3659 }
3660
3661 /*
3662 * Command LTTNG_LIST_EVENTS processed by the client thread.
3663 */
3664 ssize_t cmd_list_events(enum lttng_domain_type domain,
3665 struct ltt_session *session, char *channel_name,
3666 struct lttng_event **events, size_t *total_size)
3667 {
3668 int ret = 0;
3669 ssize_t nb_event = 0;
3670
3671 switch (domain) {
3672 case LTTNG_DOMAIN_KERNEL:
3673 if (session->kernel_session != NULL) {
3674 nb_event = list_lttng_kernel_events(channel_name,
3675 session->kernel_session, events,
3676 total_size);
3677 }
3678 break;
3679 case LTTNG_DOMAIN_UST:
3680 {
3681 if (session->ust_session != NULL) {
3682 nb_event = list_lttng_ust_global_events(channel_name,
3683 &session->ust_session->domain_global, events,
3684 total_size);
3685 }
3686 break;
3687 }
3688 case LTTNG_DOMAIN_LOG4J:
3689 case LTTNG_DOMAIN_JUL:
3690 case LTTNG_DOMAIN_PYTHON:
3691 if (session->ust_session) {
3692 struct lttng_ht_iter iter;
3693 struct agent *agt;
3694
3695 rcu_read_lock();
3696 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3697 &iter.iter, agt, node.node) {
3698 if (agt->domain == domain) {
3699 nb_event = list_lttng_agent_events(
3700 agt, events,
3701 total_size);
3702 break;
3703 }
3704 }
3705 rcu_read_unlock();
3706 }
3707 break;
3708 default:
3709 ret = LTTNG_ERR_UND;
3710 goto error;
3711 }
3712
3713 return nb_event;
3714
3715 error:
3716 /* Return negative value to differentiate return code */
3717 return -ret;
3718 }
3719
3720 /*
3721 * Using the session list, filled a lttng_session array to send back to the
3722 * client for session listing.
3723 *
3724 * The session list lock MUST be acquired before calling this function. Use
3725 * session_lock_list() and session_unlock_list().
3726 */
3727 void cmd_list_lttng_sessions(struct lttng_session *sessions,
3728 size_t session_count, uid_t uid, gid_t gid)
3729 {
3730 int ret;
3731 unsigned int i = 0;
3732 struct ltt_session *session;
3733 struct ltt_session_list *list = session_get_list();
3734 struct lttng_session_extended *extended =
3735 (typeof(extended)) (&sessions[session_count]);
3736
3737 DBG("Getting all available session for UID %d GID %d",
3738 uid, gid);
3739 /*
3740 * Iterate over session list and append data after the control struct in
3741 * the buffer.
3742 */
3743 cds_list_for_each_entry(session, &list->head, list) {
3744 if (!session_get(session)) {
3745 continue;
3746 }
3747 /*
3748 * Only list the sessions the user can control.
3749 */
3750 if (!session_access_ok(session, uid, gid) ||
3751 session->destroyed) {
3752 session_put(session);
3753 continue;
3754 }
3755
3756 struct ltt_kernel_session *ksess = session->kernel_session;
3757 struct ltt_ust_session *usess = session->ust_session;
3758
3759 if (session->consumer->type == CONSUMER_DST_NET ||
3760 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3761 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3762 ret = build_network_session_path(sessions[i].path,
3763 sizeof(sessions[i].path), session);
3764 } else {
3765 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3766 session->consumer->dst.session_root_path);
3767 }
3768 if (ret < 0) {
3769 PERROR("snprintf session path");
3770 session_put(session);
3771 continue;
3772 }
3773
3774 strncpy(sessions[i].name, session->name, NAME_MAX);
3775 sessions[i].name[NAME_MAX - 1] = '\0';
3776 sessions[i].enabled = session->active;
3777 sessions[i].snapshot_mode = session->snapshot_mode;
3778 sessions[i].live_timer_interval = session->live_timer;
3779 extended[i].creation_time.value = (uint64_t) session->creation_time;
3780 extended[i].creation_time.is_set = 1;
3781 i++;
3782 session_put(session);
3783 }
3784 }
3785
3786 /*
3787 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3788 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3789 */
3790 int cmd_data_pending(struct ltt_session *session)
3791 {
3792 int ret;
3793 struct ltt_kernel_session *ksess = session->kernel_session;
3794 struct ltt_ust_session *usess = session->ust_session;
3795
3796 assert(session);
3797
3798 DBG("Data pending for session %s", session->name);
3799
3800 /* Session MUST be stopped to ask for data availability. */
3801 if (session->active) {
3802 ret = LTTNG_ERR_SESSION_STARTED;
3803 goto error;
3804 } else {
3805 /*
3806 * If stopped, just make sure we've started before else the above call
3807 * will always send that there is data pending.
3808 *
3809 * The consumer assumes that when the data pending command is received,
3810 * the trace has been started before or else no output data is written
3811 * by the streams which is a condition for data pending. So, this is
3812 * *VERY* important that we don't ask the consumer before a start
3813 * trace.
3814 */
3815 if (!session->has_been_started) {
3816 ret = 0;
3817 goto error;
3818 }
3819 }
3820
3821 /* A rotation is still pending, we have to wait. */
3822 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
3823 DBG("Rotate still pending for session %s", session->name);
3824 ret = 1;
3825 goto error;
3826 }
3827
3828 if (ksess && ksess->consumer) {
3829 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3830 if (ret == 1) {
3831 /* Data is still being extracted for the kernel. */
3832 goto error;
3833 }
3834 }
3835
3836 if (usess && usess->consumer) {
3837 ret = consumer_is_data_pending(usess->id, usess->consumer);
3838 if (ret == 1) {
3839 /* Data is still being extracted for the kernel. */
3840 goto error;
3841 }
3842 }
3843
3844 /* Data is ready to be read by a viewer */
3845 ret = 0;
3846
3847 error:
3848 return ret;
3849 }
3850
3851 /*
3852 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3853 *
3854 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3855 */
3856 int cmd_snapshot_add_output(struct ltt_session *session,
3857 const struct lttng_snapshot_output *output, uint32_t *id)
3858 {
3859 int ret;
3860 struct snapshot_output *new_output;
3861
3862 assert(session);
3863 assert(output);
3864
3865 DBG("Cmd snapshot add output for session %s", session->name);
3866
3867 /*
3868 * Can't create an output if the session is not set in no-output mode.
3869 */
3870 if (session->output_traces) {
3871 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3872 goto error;
3873 }
3874
3875 if (session->has_non_mmap_channel) {
3876 ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
3877 goto error;
3878 }
3879
3880 /* Only one output is allowed until we have the "tee" feature. */
3881 if (session->snapshot.nb_output == 1) {
3882 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3883 goto error;
3884 }
3885
3886 new_output = snapshot_output_alloc();
3887 if (!new_output) {
3888 ret = LTTNG_ERR_NOMEM;
3889 goto error;
3890 }
3891
3892 ret = snapshot_output_init(session, output->max_size, output->name,
3893 output->ctrl_url, output->data_url, session->consumer, new_output,
3894 &session->snapshot);
3895 if (ret < 0) {
3896 if (ret == -ENOMEM) {
3897 ret = LTTNG_ERR_NOMEM;
3898 } else {
3899 ret = LTTNG_ERR_INVALID;
3900 }
3901 goto free_error;
3902 }
3903
3904 rcu_read_lock();
3905 snapshot_add_output(&session->snapshot, new_output);
3906 if (id) {
3907 *id = new_output->id;
3908 }
3909 rcu_read_unlock();
3910
3911 return LTTNG_OK;
3912
3913 free_error:
3914 snapshot_output_destroy(new_output);
3915 error:
3916 return ret;
3917 }
3918
3919 /*
3920 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3921 *
3922 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3923 */
3924 int cmd_snapshot_del_output(struct ltt_session *session,
3925 const struct lttng_snapshot_output *output)
3926 {
3927 int ret;
3928 struct snapshot_output *sout = NULL;
3929
3930 assert(session);
3931 assert(output);
3932
3933 rcu_read_lock();
3934
3935 /*
3936 * Permission denied to create an output if the session is not
3937 * set in no output mode.
3938 */
3939 if (session->output_traces) {
3940 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3941 goto error;
3942 }
3943
3944 if (output->id) {
3945 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
3946 session->name);
3947 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
3948 } else if (*output->name != '\0') {
3949 DBG("Cmd snapshot del output name %s for session %s", output->name,
3950 session->name);
3951 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
3952 }
3953 if (!sout) {
3954 ret = LTTNG_ERR_INVALID;
3955 goto error;
3956 }
3957
3958 snapshot_delete_output(&session->snapshot, sout);
3959 snapshot_output_destroy(sout);
3960 ret = LTTNG_OK;
3961
3962 error:
3963 rcu_read_unlock();
3964 return ret;
3965 }
3966
3967 /*
3968 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
3969 *
3970 * If no output is available, outputs is untouched and 0 is returned.
3971 *
3972 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
3973 */
3974 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
3975 struct lttng_snapshot_output **outputs)
3976 {
3977 int ret, idx = 0;
3978 struct lttng_snapshot_output *list = NULL;
3979 struct lttng_ht_iter iter;
3980 struct snapshot_output *output;
3981
3982 assert(session);
3983 assert(outputs);
3984
3985 DBG("Cmd snapshot list outputs for session %s", session->name);
3986
3987 /*
3988 * Permission denied to create an output if the session is not
3989 * set in no output mode.
3990 */
3991 if (session->output_traces) {
3992 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3993 goto end;
3994 }
3995
3996 if (session->snapshot.nb_output == 0) {
3997 ret = 0;
3998 goto end;
3999 }
4000
4001 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
4002 if (!list) {
4003 ret = -LTTNG_ERR_NOMEM;
4004 goto end;
4005 }
4006
4007 /* Copy list from session to the new list object. */
4008 rcu_read_lock();
4009 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
4010 output, node.node) {
4011 assert(output->consumer);
4012 list[idx].id = output->id;
4013 list[idx].max_size = output->max_size;
4014 if (lttng_strncpy(list[idx].name, output->name,
4015 sizeof(list[idx].name))) {
4016 ret = -LTTNG_ERR_INVALID;
4017 goto error;
4018 }
4019 if (output->consumer->type == CONSUMER_DST_LOCAL) {
4020 if (lttng_strncpy(list[idx].ctrl_url,
4021 output->consumer->dst.session_root_path,
4022 sizeof(list[idx].ctrl_url))) {
4023 ret = -LTTNG_ERR_INVALID;
4024 goto error;
4025 }
4026 } else {
4027 /* Control URI. */
4028 ret = uri_to_str_url(&output->consumer->dst.net.control,
4029 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
4030 if (ret < 0) {
4031 ret = -LTTNG_ERR_NOMEM;
4032 goto error;
4033 }
4034
4035 /* Data URI. */
4036 ret = uri_to_str_url(&output->consumer->dst.net.data,
4037 list[idx].data_url, sizeof(list[idx].data_url));
4038 if (ret < 0) {
4039 ret = -LTTNG_ERR_NOMEM;
4040 goto error;
4041 }
4042 }
4043 idx++;
4044 }
4045
4046 *outputs = list;
4047 list = NULL;
4048 ret = session->snapshot.nb_output;
4049 error:
4050 rcu_read_unlock();
4051 free(list);
4052 end:
4053 return ret;
4054 }
4055
4056 /*
4057 * Check if we can regenerate the metadata for this session.
4058 * Only kernel, UST per-uid and non-live sessions are supported.
4059 *
4060 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
4061 */
4062 static
4063 int check_regenerate_metadata_support(struct ltt_session *session)
4064 {
4065 int ret;
4066
4067 assert(session);
4068
4069 if (session->live_timer != 0) {
4070 ret = LTTNG_ERR_LIVE_SESSION;
4071 goto end;
4072 }
4073 if (!session->active) {
4074 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4075 goto end;
4076 }
4077 if (session->ust_session) {
4078 switch (session->ust_session->buffer_type) {
4079 case LTTNG_BUFFER_PER_UID:
4080 break;
4081 case LTTNG_BUFFER_PER_PID:
4082 ret = LTTNG_ERR_PER_PID_SESSION;
4083 goto end;
4084 default:
4085 assert(0);
4086 ret = LTTNG_ERR_UNK;
4087 goto end;
4088 }
4089 }
4090 if (session->consumer->type == CONSUMER_DST_NET &&
4091 session->consumer->relay_minor_version < 8) {
4092 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
4093 goto end;
4094 }
4095 ret = 0;
4096
4097 end:
4098 return ret;
4099 }
4100
4101 static
4102 int clear_metadata_file(int fd)
4103 {
4104 int ret;
4105 off_t lseek_ret;
4106
4107 lseek_ret = lseek(fd, 0, SEEK_SET);
4108 if (lseek_ret < 0) {
4109 PERROR("lseek");
4110 ret = -1;
4111 goto end;
4112 }
4113
4114 ret = ftruncate(fd, 0);
4115 if (ret < 0) {
4116 PERROR("ftruncate");
4117 goto end;
4118 }
4119
4120 end:
4121 return ret;
4122 }
4123
4124 static
4125 int ust_regenerate_metadata(struct ltt_ust_session *usess)
4126 {
4127 int ret = 0;
4128 struct buffer_reg_uid *uid_reg = NULL;
4129 struct buffer_reg_session *session_reg = NULL;
4130
4131 rcu_read_lock();
4132 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
4133 struct ust_registry_session *registry;
4134 struct ust_registry_channel *chan;
4135 struct lttng_ht_iter iter_chan;
4136
4137 session_reg = uid_reg->registry;
4138 registry = session_reg->reg.ust;
4139
4140 pthread_mutex_lock(&registry->lock);
4141 registry->metadata_len_sent = 0;
4142 memset(registry->metadata, 0, registry->metadata_alloc_len);
4143 registry->metadata_len = 0;
4144 registry->metadata_version++;
4145 if (registry->metadata_fd > 0) {
4146 /* Clear the metadata file's content. */
4147 ret = clear_metadata_file(registry->metadata_fd);
4148 if (ret) {
4149 pthread_mutex_unlock(&registry->lock);
4150 goto end;
4151 }
4152 }
4153
4154 ret = ust_metadata_session_statedump(registry, NULL,
4155 registry->major, registry->minor);
4156 if (ret) {
4157 pthread_mutex_unlock(&registry->lock);
4158 ERR("Failed to generate session metadata (err = %d)",
4159 ret);
4160 goto end;
4161 }
4162 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
4163 chan, node.node) {
4164 struct ust_registry_event *event;
4165 struct lttng_ht_iter iter_event;
4166
4167 ret = ust_metadata_channel_statedump(registry, chan);
4168 if (ret) {
4169 pthread_mutex_unlock(&registry->lock);
4170 ERR("Failed to generate channel metadata "
4171 "(err = %d)", ret);
4172 goto end;
4173 }
4174 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
4175 event, node.node) {
4176 ret = ust_metadata_event_statedump(registry,
4177 chan, event);
4178 if (ret) {
4179 pthread_mutex_unlock(&registry->lock);
4180 ERR("Failed to generate event metadata "
4181 "(err = %d)", ret);
4182 goto end;
4183 }
4184 }
4185 }
4186 pthread_mutex_unlock(&registry->lock);
4187 }
4188
4189 end:
4190 rcu_read_unlock();
4191 return ret;
4192 }
4193
4194 /*
4195 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
4196 *
4197 * Ask the consumer to truncate the existing metadata file(s) and
4198 * then regenerate the metadata. Live and per-pid sessions are not
4199 * supported and return an error.
4200 *
4201 * Return 0 on success or else a LTTNG_ERR code.
4202 */
4203 int cmd_regenerate_metadata(struct ltt_session *session)
4204 {
4205 int ret;
4206
4207 assert(session);
4208
4209 ret = check_regenerate_metadata_support(session);
4210 if (ret) {
4211 goto end;
4212 }
4213
4214 if (session->kernel_session) {
4215 ret = kernctl_session_regenerate_metadata(
4216 session->kernel_session->fd);
4217 if (ret < 0) {
4218 ERR("Failed to regenerate the kernel metadata");
4219 goto end;
4220 }
4221 }
4222
4223 if (session->ust_session) {
4224 ret = ust_regenerate_metadata(session->ust_session);
4225 if (ret < 0) {
4226 ERR("Failed to regenerate the UST metadata");
4227 goto end;
4228 }
4229 }
4230 DBG("Cmd metadata regenerate for session %s", session->name);
4231 ret = LTTNG_OK;
4232
4233 end:
4234 return ret;
4235 }
4236
4237 /*
4238 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
4239 *
4240 * Ask the tracer to regenerate a new statedump.
4241 *
4242 * Return 0 on success or else a LTTNG_ERR code.
4243 */
4244 int cmd_regenerate_statedump(struct ltt_session *session)
4245 {
4246 int ret;
4247
4248 assert(session);
4249
4250 if (!session->active) {
4251 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4252 goto end;
4253 }
4254
4255 if (session->kernel_session) {
4256 ret = kernctl_session_regenerate_statedump(
4257 session->kernel_session->fd);
4258 /*
4259 * Currently, the statedump in kernel can only fail if out
4260 * of memory.
4261 */
4262 if (ret < 0) {
4263 if (ret == -ENOMEM) {
4264 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
4265 } else {
4266 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4267 }
4268 ERR("Failed to regenerate the kernel statedump");
4269 goto end;
4270 }
4271 }
4272
4273 if (session->ust_session) {
4274 ret = ust_app_regenerate_statedump_all(session->ust_session);
4275 /*
4276 * Currently, the statedump in UST always returns 0.
4277 */
4278 if (ret < 0) {
4279 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4280 ERR("Failed to regenerate the UST statedump");
4281 goto end;
4282 }
4283 }
4284 DBG("Cmd regenerate statedump for session %s", session->name);
4285 ret = LTTNG_OK;
4286
4287 end:
4288 return ret;
4289 }
4290
4291 int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
4292 struct notification_thread_handle *notification_thread)
4293 {
4294 int ret;
4295 size_t trigger_len;
4296 ssize_t sock_recv_len;
4297 struct lttng_trigger *trigger = NULL;
4298 struct lttng_buffer_view view;
4299 struct lttng_dynamic_buffer trigger_buffer;
4300
4301 lttng_dynamic_buffer_init(&trigger_buffer);
4302 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4303 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4304 if (ret) {
4305 ret = LTTNG_ERR_NOMEM;
4306 goto end;
4307 }
4308
4309 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4310 trigger_len);
4311 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4312 ERR("Failed to receive \"register trigger\" command payload");
4313 /* TODO: should this be a new error enum ? */
4314 ret = LTTNG_ERR_INVALID_TRIGGER;
4315 goto end;
4316 }
4317
4318 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4319 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4320 trigger_len) {
4321 ERR("Invalid trigger payload received in \"register trigger\" command");
4322 ret = LTTNG_ERR_INVALID_TRIGGER;
4323 goto end;
4324 }
4325
4326 ret = notification_thread_command_register_trigger(notification_thread,
4327 trigger);
4328 /* Ownership of trigger was transferred. */
4329 trigger = NULL;
4330 end:
4331 lttng_trigger_destroy(trigger);
4332 lttng_dynamic_buffer_reset(&trigger_buffer);
4333 return ret;
4334 }
4335
4336 int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
4337 struct notification_thread_handle *notification_thread)
4338 {
4339 int ret;
4340 size_t trigger_len;
4341 ssize_t sock_recv_len;
4342 struct lttng_trigger *trigger = NULL;
4343 struct lttng_buffer_view view;
4344 struct lttng_dynamic_buffer trigger_buffer;
4345
4346 lttng_dynamic_buffer_init(&trigger_buffer);
4347 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4348 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4349 if (ret) {
4350 ret = LTTNG_ERR_NOMEM;
4351 goto end;
4352 }
4353
4354 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4355 trigger_len);
4356 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4357 ERR("Failed to receive \"unregister trigger\" command payload");
4358 /* TODO: should this be a new error enum ? */
4359 ret = LTTNG_ERR_INVALID_TRIGGER;
4360 goto end;
4361 }
4362
4363 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4364 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4365 trigger_len) {
4366 ERR("Invalid trigger payload received in \"unregister trigger\" command");
4367 ret = LTTNG_ERR_INVALID_TRIGGER;
4368 goto end;
4369 }
4370
4371 ret = notification_thread_command_unregister_trigger(notification_thread,
4372 trigger);
4373 end:
4374 lttng_trigger_destroy(trigger);
4375 lttng_dynamic_buffer_reset(&trigger_buffer);
4376 return ret;
4377 }
4378
4379 /*
4380 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4381 * snapshot output is *not* set with a remote destination.
4382 *
4383 * Return LTTNG_OK on success or a LTTNG_ERR code.
4384 */
4385 static enum lttng_error_code set_relayd_for_snapshot(
4386 struct consumer_output *output,
4387 const struct ltt_session *session)
4388 {
4389 enum lttng_error_code status = LTTNG_OK;
4390 struct lttng_ht_iter iter;
4391 struct consumer_socket *socket;
4392 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
4393 const char *base_path;
4394
4395 assert(output);
4396 assert(session);
4397
4398 DBG2("Set relayd object from snapshot output");
4399
4400 if (session->current_trace_chunk) {
4401 enum lttng_trace_chunk_status chunk_status =
4402 lttng_trace_chunk_get_id(
4403 session->current_trace_chunk,
4404 &current_chunk_id.value);
4405
4406 if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK) {
4407 current_chunk_id.is_set = true;
4408 } else {
4409 ERR("Failed to get current trace chunk id");
4410 status = LTTNG_ERR_UNK;
4411 goto error;
4412 }
4413 }
4414
4415 /* Ignore if snapshot consumer output is not network. */
4416 if (output->type != CONSUMER_DST_NET) {
4417 goto error;
4418 }
4419
4420 /*
4421 * The snapshot record URI base path overrides the session
4422 * base path.
4423 */
4424 if (output->dst.net.control.subdir[0] != '\0') {
4425 base_path = output->dst.net.control.subdir;
4426 } else {
4427 base_path = session->base_path;
4428 }
4429
4430 /*
4431 * For each consumer socket, create and send the relayd object of the
4432 * snapshot output.
4433 */
4434 rcu_read_lock();
4435 cds_lfht_for_each_entry(output->socks->ht, &iter.iter,
4436 socket, node.node) {
4437 pthread_mutex_lock(socket->lock);
4438 status = send_consumer_relayd_sockets(0, session->id,
4439 output, socket,
4440 session->name, session->hostname,
4441 base_path,
4442 session->live_timer,
4443 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
4444 session->creation_time,
4445 session->name_contains_creation_time);
4446 pthread_mutex_unlock(socket->lock);
4447 if (status != LTTNG_OK) {
4448 rcu_read_unlock();
4449 goto error;
4450 }
4451 }
4452 rcu_read_unlock();
4453
4454 error:
4455 return status;
4456 }
4457
4458 /*
4459 * Record a kernel snapshot.
4460 *
4461 * Return LTTNG_OK on success or a LTTNG_ERR code.
4462 */
4463 static enum lttng_error_code record_kernel_snapshot(
4464 struct ltt_kernel_session *ksess,
4465 const struct consumer_output *output,
4466 const struct ltt_session *session,
4467 int wait, uint64_t nb_packets_per_stream)
4468 {
4469 enum lttng_error_code status;
4470
4471 assert(ksess);
4472 assert(output);
4473 assert(session);
4474
4475 status = kernel_snapshot_record(
4476 ksess, output, wait, nb_packets_per_stream);
4477 return status;
4478 }
4479
4480 /*
4481 * Record a UST snapshot.
4482 *
4483 * Returns LTTNG_OK on success or a LTTNG_ERR error code.
4484 */
4485 static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
4486 const struct consumer_output *output,
4487 const struct ltt_session *session,
4488 int wait, uint64_t nb_packets_per_stream)
4489 {
4490 enum lttng_error_code status;
4491
4492 assert(usess);
4493 assert(output);
4494 assert(session);
4495
4496 status = ust_app_snapshot_record(
4497 usess, output, wait, nb_packets_per_stream);
4498 return status;
4499 }
4500
4501 static
4502 uint64_t get_session_size_one_more_packet_per_stream(
4503 const struct ltt_session *session, uint64_t cur_nr_packets)
4504 {
4505 uint64_t tot_size = 0;
4506
4507 if (session->kernel_session) {
4508 struct ltt_kernel_channel *chan;
4509 const struct ltt_kernel_session *ksess =
4510 session->kernel_session;
4511
4512 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
4513 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
4514 /*
4515 * Don't take channel into account if we
4516 * already grab all its packets.
4517 */
4518 continue;
4519 }
4520 tot_size += chan->channel->attr.subbuf_size
4521 * chan->stream_count;
4522 }
4523 }
4524
4525 if (session->ust_session) {
4526 const struct ltt_ust_session *usess = session->ust_session;
4527
4528 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
4529 cur_nr_packets);
4530 }
4531
4532 return tot_size;
4533 }
4534
4535 /*
4536 * Calculate the number of packets we can grab from each stream that
4537 * fits within the overall snapshot max size.
4538 *
4539 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
4540 * the number of packets per stream.
4541 *
4542 * TODO: this approach is not perfect: we consider the worse case
4543 * (packet filling the sub-buffers) as an upper bound, but we could do
4544 * better if we do this calculation while we actually grab the packet
4545 * content: we would know how much padding we don't actually store into
4546 * the file.
4547 *
4548 * This algorithm is currently bounded by the number of packets per
4549 * stream.
4550 *
4551 * Since we call this algorithm before actually grabbing the data, it's
4552 * an approximation: for instance, applications could appear/disappear
4553 * in between this call and actually grabbing data.
4554 */
4555 static
4556 int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
4557 uint64_t max_size)
4558 {
4559 int64_t size_left;
4560 uint64_t cur_nb_packets = 0;
4561
4562 if (!max_size) {
4563 return 0; /* Infinite */
4564 }
4565
4566 size_left = max_size;
4567 for (;;) {
4568 uint64_t one_more_packet_tot_size;
4569
4570 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(
4571 session, cur_nb_packets);
4572 if (!one_more_packet_tot_size) {
4573 /* We are already grabbing all packets. */
4574 break;
4575 }
4576 size_left -= one_more_packet_tot_size;
4577 if (size_left < 0) {
4578 break;
4579 }
4580 cur_nb_packets++;
4581 }
4582 if (!cur_nb_packets) {
4583 /* Not enough room to grab one packet of each stream, error. */
4584 return -1;
4585 }
4586 return cur_nb_packets;
4587 }
4588
4589 static
4590 enum lttng_error_code snapshot_record(struct ltt_session *session,
4591 const struct snapshot_output *snapshot_output, int wait)
4592 {
4593 int64_t nb_packets_per_stream;
4594 char snapshot_chunk_name[LTTNG_NAME_MAX];
4595 int ret;
4596 enum lttng_error_code ret_code = LTTNG_OK;
4597 struct lttng_trace_chunk *snapshot_trace_chunk;
4598 struct consumer_output *original_ust_consumer_output = NULL;
4599 struct consumer_output *original_kernel_consumer_output = NULL;
4600 struct consumer_output *snapshot_ust_consumer_output = NULL;
4601 struct consumer_output *snapshot_kernel_consumer_output = NULL;
4602
4603 ret = snprintf(snapshot_chunk_name, sizeof(snapshot_chunk_name),
4604 "%s-%s-%" PRIu64,
4605 snapshot_output->name,
4606 snapshot_output->datetime,
4607 snapshot_output->nb_snapshot);
4608 if (ret < 0 || ret >= sizeof(snapshot_chunk_name)) {
4609 ERR("Failed to format snapshot name");
4610 ret_code = LTTNG_ERR_INVALID;
4611 goto error;
4612 }
4613 DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
4614 snapshot_output->name, session->name,
4615 snapshot_chunk_name);
4616 if (!session->kernel_session && !session->ust_session) {
4617 ERR("Failed to record snapshot as no channels exist");
4618 ret_code = LTTNG_ERR_NO_CHANNEL;
4619 goto error;
4620 }
4621
4622 if (session->kernel_session) {
4623 original_kernel_consumer_output =
4624 session->kernel_session->consumer;
4625 snapshot_kernel_consumer_output =
4626 consumer_copy_output(snapshot_output->consumer);
4627 strcpy(snapshot_kernel_consumer_output->chunk_path,
4628 snapshot_chunk_name);
4629 ret = consumer_copy_sockets(snapshot_kernel_consumer_output,
4630 original_kernel_consumer_output);
4631 if (ret < 0) {
4632 ERR("Failed to copy consumer sockets from snapshot output configuration");
4633 ret_code = LTTNG_ERR_NOMEM;
4634 goto error;
4635 }
4636 ret_code = set_relayd_for_snapshot(
4637 snapshot_kernel_consumer_output, session);
4638 if (ret_code != LTTNG_OK) {
4639 ERR("Failed to setup relay daemon for kernel tracer snapshot");
4640 goto error;
4641 }
4642 session->kernel_session->consumer =
4643 snapshot_kernel_consumer_output;
4644 }
4645 if (session->ust_session) {
4646 original_ust_consumer_output = session->ust_session->consumer;
4647 snapshot_ust_consumer_output =
4648 consumer_copy_output(snapshot_output->consumer);
4649 strcpy(snapshot_ust_consumer_output->chunk_path,
4650 snapshot_chunk_name);
4651 ret = consumer_copy_sockets(snapshot_ust_consumer_output,
4652 original_ust_consumer_output);
4653 if (ret < 0) {
4654 ERR("Failed to copy consumer sockets from snapshot output configuration");
4655 ret_code = LTTNG_ERR_NOMEM;
4656 goto error;
4657 }
4658 ret_code = set_relayd_for_snapshot(
4659 snapshot_ust_consumer_output, session);
4660 if (ret_code != LTTNG_OK) {
4661 ERR("Failed to setup relay daemon for userspace tracer snapshot");
4662 goto error;
4663 }
4664 session->ust_session->consumer =
4665 snapshot_ust_consumer_output;
4666 }
4667
4668 snapshot_trace_chunk = session_create_new_trace_chunk(session,
4669 snapshot_kernel_consumer_output ?:
4670 snapshot_ust_consumer_output,
4671 consumer_output_get_base_path(
4672 snapshot_output->consumer),
4673 snapshot_chunk_name);
4674 if (!snapshot_trace_chunk) {
4675 ERR("Failed to create temporary trace chunk to record a snapshot of session \"%s\"",
4676 session->name);
4677 ret_code = LTTNG_ERR_CREATE_DIR_FAIL;
4678 goto error;
4679 }
4680 assert(!session->current_trace_chunk);
4681 ret = session_set_trace_chunk(session, snapshot_trace_chunk, NULL);
4682 lttng_trace_chunk_put(snapshot_trace_chunk);
4683 snapshot_trace_chunk = NULL;
4684 if (ret) {
4685 ERR("Failed to set temporary trace chunk to record a snapshot of session \"%s\"",
4686 session->name);
4687 ret_code = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
4688 goto error;
4689 }
4690
4691 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
4692 snapshot_output->max_size);
4693 if (nb_packets_per_stream < 0) {
4694 ret_code = LTTNG_ERR_MAX_SIZE_INVALID;
4695 goto error;
4696 }
4697
4698 if (session->kernel_session) {
4699 ret_code = record_kernel_snapshot(session->kernel_session,
4700 snapshot_kernel_consumer_output, session,
4701 wait, nb_packets_per_stream);
4702 if (ret_code != LTTNG_OK) {
4703 goto error;
4704 }
4705 }
4706
4707 if (session->ust_session) {
4708 ret_code = record_ust_snapshot(session->ust_session,
4709 snapshot_ust_consumer_output, session,
4710 wait, nb_packets_per_stream);
4711 if (ret_code != LTTNG_OK) {
4712 goto error;
4713 }
4714 }
4715
4716 if (session_close_trace_chunk(session, session->current_trace_chunk,
4717 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION, NULL)) {
4718 /*
4719 * Don't goto end; make sure the chunk is closed for the session
4720 * to allow future snapshots.
4721 */
4722 ERR("Failed to close snapshot trace chunk of session \"%s\"",
4723 session->name);
4724 ret_code = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
4725 }
4726 if (session_set_trace_chunk(session, NULL, NULL)) {
4727 ERR("Failed to release the current trace chunk of session \"%s\"",
4728 session->name);
4729 ret_code = LTTNG_ERR_UNK;
4730 }
4731 error:
4732 if (original_ust_consumer_output) {
4733 session->ust_session->consumer = original_ust_consumer_output;
4734 }
4735 if (original_kernel_consumer_output) {
4736 session->kernel_session->consumer =
4737 original_kernel_consumer_output;
4738 }
4739 consumer_output_put(snapshot_ust_consumer_output);
4740 consumer_output_put(snapshot_kernel_consumer_output);
4741 return ret_code;
4742 }
4743
4744 /*
4745 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
4746 *
4747 * The wait parameter is ignored so this call always wait for the snapshot to
4748 * complete before returning.
4749 *
4750 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4751 */
4752 int cmd_snapshot_record(struct ltt_session *session,
4753 const struct lttng_snapshot_output *output, int wait)
4754 {
4755 enum lttng_error_code cmd_ret = LTTNG_OK;
4756 int ret;
4757 unsigned int snapshot_success = 0;
4758 char datetime[16];
4759 struct snapshot_output *tmp_output = NULL;
4760
4761 assert(session);
4762 assert(output);
4763
4764 DBG("Cmd snapshot record for session %s", session->name);
4765
4766 /* Get the datetime for the snapshot output directory. */
4767 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
4768 sizeof(datetime));
4769 if (!ret) {
4770 cmd_ret = LTTNG_ERR_INVALID;
4771 goto error;
4772 }
4773
4774 /*
4775 * Permission denied to create an output if the session is not
4776 * set in no output mode.
4777 */
4778 if (session->output_traces) {
4779 cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4780 goto error;
4781 }
4782
4783 /* The session needs to be started at least once. */
4784 if (!session->has_been_started) {
4785 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4786 goto error;
4787 }
4788
4789 /* Use temporary output for the session. */
4790 if (*output->ctrl_url != '\0') {
4791 tmp_output = snapshot_output_alloc();
4792 if (!tmp_output) {
4793 cmd_ret = LTTNG_ERR_NOMEM;
4794 goto error;
4795 }
4796
4797 ret = snapshot_output_init(session, output->max_size,
4798 output->name,
4799 output->ctrl_url, output->data_url,
4800 session->consumer,
4801 tmp_output, NULL);
4802 if (ret < 0) {
4803 if (ret == -ENOMEM) {
4804 cmd_ret = LTTNG_ERR_NOMEM;
4805 } else {
4806 cmd_ret = LTTNG_ERR_INVALID;
4807 }
4808 goto error;
4809 }
4810 /* Use the global session count for the temporary snapshot. */
4811 tmp_output->nb_snapshot = session->snapshot.nb_snapshot;
4812
4813 /* Use the global datetime */
4814 memcpy(tmp_output->datetime, datetime, sizeof(datetime));
4815 cmd_ret = snapshot_record(session, tmp_output, wait);
4816 if (cmd_ret != LTTNG_OK) {
4817 goto error;
4818 }
4819 snapshot_success = 1;
4820 } else {
4821 struct snapshot_output *sout;
4822 struct lttng_ht_iter iter;
4823
4824 rcu_read_lock();
4825 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
4826 &iter.iter, sout, node.node) {
4827 struct snapshot_output output_copy;
4828
4829 /*
4830 * Make a local copy of the output and override output
4831 * parameters with those provided as part of the
4832 * command.
4833 */
4834 memcpy(&output_copy, sout, sizeof(output_copy));
4835
4836 if (output->max_size != (uint64_t) -1ULL) {
4837 output_copy.max_size = output->max_size;
4838 }
4839
4840 output_copy.nb_snapshot = session->snapshot.nb_snapshot;
4841 memcpy(output_copy.datetime, datetime,
4842 sizeof(datetime));
4843
4844 /* Use temporary name. */
4845 if (*output->name != '\0') {
4846 if (lttng_strncpy(output_copy.name,
4847 output->name,
4848 sizeof(output_copy.name))) {
4849 cmd_ret = LTTNG_ERR_INVALID;
4850 rcu_read_unlock();
4851 goto error;
4852 }
4853 }
4854
4855 cmd_ret = snapshot_record(session, &output_copy, wait);
4856 if (cmd_ret != LTTNG_OK) {
4857 rcu_read_unlock();
4858 goto error;
4859 }
4860 snapshot_success = 1;
4861 }
4862 rcu_read_unlock();
4863 }
4864
4865 if (snapshot_success) {
4866 session->snapshot.nb_snapshot++;
4867 } else {
4868 cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
4869 }
4870
4871 error:
4872 if (tmp_output) {
4873 snapshot_output_destroy(tmp_output);
4874 }
4875 return cmd_ret;
4876 }
4877
4878 /*
4879 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
4880 */
4881 int cmd_set_session_shm_path(struct ltt_session *session,
4882 const char *shm_path)
4883 {
4884 /* Safety net */
4885 assert(session);
4886
4887 /*
4888 * Can only set shm path before session is started.
4889 */
4890 if (session->has_been_started) {
4891 return LTTNG_ERR_SESSION_STARTED;
4892 }
4893
4894 strncpy(session->shm_path, shm_path,
4895 sizeof(session->shm_path));
4896 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
4897
4898 return 0;
4899 }
4900
4901 /*
4902 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
4903 *
4904 * Ask the consumer to rotate the session output directory.
4905 * The session lock must be held.
4906 *
4907 * Returns LTTNG_OK on success or else a negative LTTng error code.
4908 */
4909 int cmd_rotate_session(struct ltt_session *session,
4910 struct lttng_rotate_session_return *rotate_return,
4911 bool quiet_rotation,
4912 enum lttng_trace_chunk_command_type command)
4913 {
4914 int ret;
4915 uint64_t ongoing_rotation_chunk_id;
4916 enum lttng_error_code cmd_ret = LTTNG_OK;
4917 struct lttng_trace_chunk *chunk_being_archived = NULL;
4918 struct lttng_trace_chunk *new_trace_chunk = NULL;
4919 enum lttng_trace_chunk_status chunk_status;
4920 bool failed_to_rotate = false;
4921 enum lttng_error_code rotation_fail_code = LTTNG_OK;
4922
4923 assert(session);
4924
4925 if (!session->has_been_started) {
4926 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4927 goto end;
4928 }
4929
4930 /*
4931 * Explicit rotation is not supported for live sessions.
4932 * However, live sessions can perform a quiet rotation on
4933 * destroy.
4934 * Rotation is not supported for snapshot traces (no output).
4935 */
4936 if ((!quiet_rotation && session->live_timer) ||
4937 !session->output_traces) {
4938 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
4939 goto end;
4940 }
4941
4942 /* Unsupported feature in lttng-relayd before 2.11. */
4943 if (!quiet_rotation && session->consumer->type == CONSUMER_DST_NET &&
4944 (session->consumer->relay_major_version == 2 &&
4945 session->consumer->relay_minor_version < 11)) {
4946 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
4947 goto end;
4948 }
4949
4950 /* Unsupported feature in lttng-modules before 2.8 (lack of sequence number). */
4951 if (session->kernel_session && !kernel_supports_ring_buffer_packet_sequence_number()) {
4952 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL;
4953 goto end;
4954 }
4955
4956 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
4957 DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
4958 session->name);
4959 cmd_ret = LTTNG_ERR_ROTATION_PENDING;
4960 goto end;
4961 }
4962
4963 /*
4964 * After a stop, we only allow one rotation to occur, the other ones are
4965 * useless until a new start.
4966 */
4967 if (session->rotated_after_last_stop) {
4968 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
4969 session->name);
4970 cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
4971 goto end;
4972 }
4973
4974 /*
4975 * After a stop followed by a clear, disallow following rotations a they would
4976 * generate empty chunks.
4977 */
4978 if (session->cleared_after_last_stop) {
4979 DBG("Session \"%s\" was already cleared after stop, refusing rotation",
4980 session->name);
4981 cmd_ret = LTTNG_ERR_ROTATION_AFTER_STOP_CLEAR;
4982 goto end;
4983 }
4984
4985 if (session->active) {
4986 new_trace_chunk = session_create_new_trace_chunk(session, NULL,
4987 NULL, NULL);
4988 if (!new_trace_chunk) {
4989 cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
4990 goto error;
4991 }
4992 }
4993
4994 /*
4995 * The current trace chunk becomes the chunk being archived.
4996 *
4997 * After this point, "chunk_being_archived" must absolutely
4998 * be closed on the consumer(s), otherwise it will never be
4999 * cleaned-up, which will result in a leak.
5000 */
5001 ret = session_set_trace_chunk(session, new_trace_chunk,
5002 &chunk_being_archived);
5003 if (ret) {
5004 cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
5005 goto error;
5006 }
5007
5008 if (session->kernel_session) {
5009 cmd_ret = kernel_rotate_session(session);
5010 if (cmd_ret != LTTNG_OK) {
5011 failed_to_rotate = true;
5012 rotation_fail_code = cmd_ret;
5013 }
5014 }
5015 if (session->ust_session) {
5016 cmd_ret = ust_app_rotate_session(session);
5017 if (cmd_ret != LTTNG_OK) {
5018 failed_to_rotate = true;
5019 rotation_fail_code = cmd_ret;
5020 }
5021 }
5022
5023 if (!session->active) {
5024 session->rotated_after_last_stop = true;
5025 }
5026
5027 if (!chunk_being_archived) {
5028 DBG("Rotating session \"%s\" from a \"NULL\" trace chunk to a new trace chunk, skipping completion check",
5029 session->name);
5030 if (failed_to_rotate) {
5031 cmd_ret = rotation_fail_code;
5032 goto error;
5033 }
5034 cmd_ret = LTTNG_OK;
5035 goto end;
5036 }
5037
5038 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
5039 chunk_status = lttng_trace_chunk_get_id(chunk_being_archived,
5040 &ongoing_rotation_chunk_id);
5041 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5042
5043 ret = session_close_trace_chunk(session, chunk_being_archived,
5044 command, session->last_chunk_path);
5045 if (ret) {
5046 cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5047 goto error;
5048 }
5049
5050 if (failed_to_rotate) {
5051 cmd_ret = rotation_fail_code;
5052 goto error;
5053 }
5054
5055 session->quiet_rotation = quiet_rotation;
5056 ret = timer_session_rotation_pending_check_start(session,
5057 DEFAULT_ROTATE_PENDING_TIMER);
5058 if (ret) {
5059 cmd_ret = LTTNG_ERR_UNK;
5060 goto error;
5061 }
5062
5063 if (rotate_return) {
5064 rotate_return->rotation_id = ongoing_rotation_chunk_id;
5065 }
5066
5067 session->chunk_being_archived = chunk_being_archived;
5068 chunk_being_archived = NULL;
5069 if (!quiet_rotation) {
5070 ret = notification_thread_command_session_rotation_ongoing(
5071 notification_thread_handle,
5072 session->name, session->uid, session->gid,
5073 ongoing_rotation_chunk_id);
5074 if (ret != LTTNG_OK) {
5075 ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
5076 session->name);
5077 cmd_ret = ret;
5078 }
5079 }
5080
5081 DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
5082 session->name, ongoing_rotation_chunk_id);
5083 end:
5084 lttng_trace_chunk_put(new_trace_chunk);
5085 lttng_trace_chunk_put(chunk_being_archived);
5086 ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
5087 return ret;
5088 error:
5089 if (session_reset_rotation_state(session,
5090 LTTNG_ROTATION_STATE_ERROR)) {
5091 ERR("Failed to reset rotation state of session \"%s\"",
5092 session->name);
5093 }
5094 goto end;
5095 }
5096
5097 /*
5098 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
5099 *
5100 * Check if the session has finished its rotation.
5101 *
5102 * Return LTTNG_OK on success or else an LTTNG_ERR code.
5103 */
5104 int cmd_rotate_get_info(struct ltt_session *session,
5105 struct lttng_rotation_get_info_return *info_return,
5106 uint64_t rotation_id)
5107 {
5108 enum lttng_error_code cmd_ret = LTTNG_OK;
5109 enum lttng_rotation_state rotation_state;
5110
5111 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
5112 session->most_recent_chunk_id.value);
5113
5114 if (session->chunk_being_archived) {
5115 enum lttng_trace_chunk_status chunk_status;
5116 uint64_t chunk_id;
5117
5118 chunk_status = lttng_trace_chunk_get_id(
5119 session->chunk_being_archived,
5120 &chunk_id);
5121 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5122
5123 rotation_state = rotation_id == chunk_id ?
5124 LTTNG_ROTATION_STATE_ONGOING :
5125 LTTNG_ROTATION_STATE_EXPIRED;
5126 } else {
5127 if (session->last_archived_chunk_id.is_set &&
5128 rotation_id != session->last_archived_chunk_id.value) {
5129 rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
5130 } else {
5131 rotation_state = session->rotation_state;
5132 }
5133 }
5134
5135 switch (rotation_state) {
5136 case LTTNG_ROTATION_STATE_NO_ROTATION:
5137 DBG("Reporting that no rotation has occurred within the lifetime of session \"%s\"",
5138 session->name);
5139 goto end;
5140 case LTTNG_ROTATION_STATE_EXPIRED:
5141 DBG("Reporting that the rotation state of rotation id %" PRIu64 " of session \"%s\" has expired",
5142 rotation_id, session->name);
5143 break;
5144 case LTTNG_ROTATION_STATE_ONGOING:
5145 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
5146 rotation_id, session->name);
5147 break;
5148 case LTTNG_ROTATION_STATE_COMPLETED:
5149 {
5150 int fmt_ret;
5151 char *chunk_path;
5152 char *current_tracing_path_reply;
5153 size_t current_tracing_path_reply_len;
5154
5155 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
5156 rotation_id, session->name);
5157
5158 switch (session_get_consumer_destination_type(session)) {
5159 case CONSUMER_DST_LOCAL:
5160 current_tracing_path_reply =
5161 info_return->location.local.absolute_path;
5162 current_tracing_path_reply_len =
5163 sizeof(info_return->location.local.absolute_path);
5164 info_return->location_type =
5165 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
5166 fmt_ret = asprintf(&chunk_path,
5167 "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
5168 session_get_base_path(session),
5169 session->last_archived_chunk_name);
5170 if (fmt_ret == -1) {
5171 PERROR("Failed to format the path of the last archived trace chunk");
5172 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5173 cmd_ret = LTTNG_ERR_UNK;
5174 goto end;
5175 }
5176 break;
5177 case CONSUMER_DST_NET:
5178 {
5179 uint16_t ctrl_port, data_port;
5180
5181 current_tracing_path_reply =
5182 info_return->location.relay.relative_path;
5183 current_tracing_path_reply_len =
5184 sizeof(info_return->location.relay.relative_path);
5185 /* Currently the only supported relay protocol. */
5186 info_return->location.relay.protocol =
5187 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
5188
5189 fmt_ret = lttng_strncpy(info_return->location.relay.host,
5190 session_get_net_consumer_hostname(session),
5191 sizeof(info_return->location.relay.host));
5192 if (fmt_ret) {
5193 ERR("Failed to copy host name to rotate_get_info reply");
5194 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5195 cmd_ret = LTTNG_ERR_SET_URL;
5196 goto end;
5197 }
5198
5199 session_get_net_consumer_ports(session, &ctrl_port, &data_port);
5200 info_return->location.relay.ports.control = ctrl_port;
5201 info_return->location.relay.ports.data = data_port;
5202 info_return->location_type =
5203 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
5204 chunk_path = strdup(session->last_chunk_path);
5205 if (!chunk_path) {
5206 ERR("Failed to allocate the path of the last archived trace chunk");
5207 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5208 cmd_ret = LTTNG_ERR_UNK;
5209 goto end;
5210 }
5211 break;
5212 }
5213 default:
5214 abort();
5215 }
5216
5217 fmt_ret = lttng_strncpy(current_tracing_path_reply,
5218 chunk_path, current_tracing_path_reply_len);
5219 free(chunk_path);
5220 if (fmt_ret) {
5221 ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
5222 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5223 cmd_ret = LTTNG_ERR_UNK;
5224 goto end;
5225 }
5226
5227 break;
5228 }
5229 case LTTNG_ROTATION_STATE_ERROR:
5230 DBG("Reporting that an error occurred during rotation %" PRIu64 " of session \"%s\"",
5231 rotation_id, session->name);
5232 break;
5233 default:
5234 abort();
5235 }
5236
5237 cmd_ret = LTTNG_OK;
5238 end:
5239 info_return->status = (int32_t) rotation_state;
5240 return cmd_ret;
5241 }
5242
5243 /*
5244 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
5245 *
5246 * Configure the automatic rotation parameters.
5247 * 'activate' to true means activate the rotation schedule type with 'new_value'.
5248 * 'activate' to false means deactivate the rotation schedule and validate that
5249 * 'new_value' has the same value as the currently active value.
5250 *
5251 * Return 0 on success or else a positive LTTNG_ERR code.
5252 */
5253 int cmd_rotation_set_schedule(struct ltt_session *session,
5254 bool activate, enum lttng_rotation_schedule_type schedule_type,
5255 uint64_t new_value,
5256 struct notification_thread_handle *notification_thread_handle)
5257 {
5258 int ret;
5259 uint64_t *parameter_value;
5260
5261 assert(session);
5262
5263 DBG("Cmd rotate set schedule session %s", session->name);
5264
5265 if (session->live_timer || !session->output_traces) {
5266 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
5267 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5268 goto end;
5269 }
5270
5271 switch (schedule_type) {
5272 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5273 parameter_value = &session->rotate_size;
5274 break;
5275 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5276 parameter_value = &session->rotate_timer_period;
5277 if (new_value >= UINT_MAX) {
5278 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
5279 new_value, UINT_MAX);
5280 ret = LTTNG_ERR_INVALID;
5281 goto end;
5282 }
5283 break;
5284 default:
5285 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
5286 ret = LTTNG_ERR_INVALID;
5287 goto end;
5288 }
5289
5290 /* Improper use of the API. */
5291 if (new_value == -1ULL) {
5292 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
5293 ret = LTTNG_ERR_INVALID;
5294 goto end;
5295 }
5296
5297 /*
5298 * As indicated in struct ltt_session's comments, a value of == 0 means
5299 * this schedule rotation type is not in use.
5300 *
5301 * Reject the command if we were asked to activate a schedule that was
5302 * already active.
5303 */
5304 if (activate && *parameter_value != 0) {
5305 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
5306 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
5307 goto end;
5308 }
5309
5310 /*
5311 * Reject the command if we were asked to deactivate a schedule that was
5312 * not active.
5313 */
5314 if (!activate && *parameter_value == 0) {
5315 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
5316 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5317 goto end;
5318 }
5319
5320 /*
5321 * Reject the command if we were asked to deactivate a schedule that
5322 * doesn't exist.
5323 */
5324 if (!activate && *parameter_value != new_value) {
5325 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
5326 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5327 goto end;
5328 }
5329
5330 *parameter_value = activate ? new_value : 0;
5331
5332 switch (schedule_type) {
5333 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5334 if (activate && session->active) {
5335 /*
5336 * Only start the timer if the session is active,
5337 * otherwise it will be started when the session starts.
5338 */
5339 ret = timer_session_rotation_schedule_timer_start(
5340 session, new_value);
5341 if (ret) {
5342 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
5343 ret = LTTNG_ERR_UNK;
5344 goto end;
5345 }
5346 } else {
5347 ret = timer_session_rotation_schedule_timer_stop(
5348 session);
5349 if (ret) {
5350 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
5351 ret = LTTNG_ERR_UNK;
5352 goto end;
5353 }
5354 }
5355 break;
5356 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5357 if (activate) {
5358 ret = subscribe_session_consumed_size_rotation(session,
5359 new_value, notification_thread_handle);
5360 if (ret) {
5361 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
5362 ret = LTTNG_ERR_UNK;
5363 goto end;
5364 }
5365 } else {
5366 ret = unsubscribe_session_consumed_size_rotation(session,
5367 notification_thread_handle);
5368 if (ret) {
5369 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
5370 ret = LTTNG_ERR_UNK;
5371 goto end;
5372 }
5373
5374 }
5375 break;
5376 default:
5377 /* Would have been caught before. */
5378 abort();
5379 }
5380
5381 ret = LTTNG_OK;
5382
5383 goto end;
5384
5385 end:
5386 return ret;
5387 }
5388
5389 /* Wait for a given path to be removed before continuing. */
5390 static enum lttng_error_code wait_on_path(void *path_data)
5391 {
5392 const char *shm_path = path_data;
5393
5394 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5395 shm_path);
5396 while (true) {
5397 int ret;
5398 struct stat st;
5399
5400 ret = stat(shm_path, &st);
5401 if (ret) {
5402 if (errno != ENOENT) {
5403 PERROR("stat() returned an error while checking for the existence of the shm path");
5404 } else {
5405 DBG("shm path no longer exists, completing the destruction of session");
5406 }
5407 break;
5408 } else {
5409 if (!S_ISDIR(st.st_mode)) {
5410 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5411 shm_path);
5412 break;
5413 }
5414 }
5415 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
5416 }
5417 return LTTNG_OK;
5418 }
5419
5420 /*
5421 * Returns a pointer to a handler to run on completion of a command.
5422 * Returns NULL if no handler has to be run for the last command executed.
5423 */
5424 const struct cmd_completion_handler *cmd_pop_completion_handler(void)
5425 {
5426 struct cmd_completion_handler *handler = current_completion_handler;
5427
5428 current_completion_handler = NULL;
5429 return handler;
5430 }
5431
5432 /*
5433 * Init command subsystem.
5434 */
5435 void cmd_init(void)
5436 {
5437 /*
5438 * Set network sequence index to 1 for streams to match a relayd
5439 * socket on the consumer side.
5440 */
5441 pthread_mutex_lock(&relayd_net_seq_idx_lock);
5442 relayd_net_seq_idx = 1;
5443 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
5444
5445 DBG("Command subsystem initialized");
5446 }
LTTng tools - Deliverables
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