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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->most_recent_chunk_id.is_set &&
3332 session->most_recent_chunk_id.value != 0 &&
3333 session->current_trace_chunk && session->output_traces) {
3334 /*
3335 * Perform a last rotation on destruction if rotations have
3336 * occurred during the session's lifetime.
3337 */
3338 ret = cmd_rotate_session(session, NULL, false,
3339 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
3340 if (ret != LTTNG_OK) {
3341 ERR("Failed to perform an implicit rotation as part of the destruction of session \"%s\": %s",
3342 session->name, lttng_strerror(-ret));
3343 destruction_last_error = -ret;
3344 }
3345 if (reply_context) {
3346 reply_context->implicit_rotation_on_destroy = true;
3347 }
3348 } else if (session->has_been_started && session->current_trace_chunk) {
3349 /*
3350 * The user has not triggered a session rotation. However, to
3351 * ensure all data has been consumed, the session is rotated
3352 * to a 'null' trace chunk before it is destroyed.
3353 *
3354 * This is a "quiet" rotation meaning that no notification is
3355 * emitted and no renaming of the current trace chunk takes
3356 * place.
3357 */
3358 ret = cmd_rotate_session(session, NULL, true,
3359 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
3360 if (ret != LTTNG_OK) {
3361 ERR("Failed to perform a quiet rotation as part of the destruction of session \"%s\": %s",
3362 session->name, lttng_strerror(-ret));
3363 destruction_last_error = -ret;
3364 }
3365 }
3366
3367 if (session->shm_path[0]) {
3368 /*
3369 * When a session is created with an explicit shm_path,
3370 * the consumer daemon will create its shared memory files
3371 * at that location and will *not* unlink them. This is normal
3372 * as the intention of that feature is to make it possible
3373 * to retrieve the content of those files should a crash occur.
3374 *
3375 * To ensure the content of those files can be used, the
3376 * sessiond daemon will replicate the content of the metadata
3377 * cache in a metadata file.
3378 *
3379 * On clean-up, it is expected that the consumer daemon will
3380 * unlink the shared memory files and that the session daemon
3381 * will unlink the metadata file. Then, the session's directory
3382 * in the shm path can be removed.
3383 *
3384 * Unfortunately, a flaw in the design of the sessiond's and
3385 * consumerd's tear down of channels makes it impossible to
3386 * determine when the sessiond _and_ the consumerd have both
3387 * destroyed their representation of a channel. For one, the
3388 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3389 * callbacks in both daemons.
3390 *
3391 * However, it is also impossible for the sessiond to know when
3392 * the consumer daemon is done destroying its channel(s) since
3393 * it occurs as a reaction to the closing of the channel's file
3394 * descriptor. There is no resulting communication initiated
3395 * from the consumerd to the sessiond to confirm that the
3396 * operation is completed (and was successful).
3397 *
3398 * Until this is all fixed, the session daemon checks for the
3399 * removal of the session's shm path which makes it possible
3400 * to safely advertise a session as having been destroyed.
3401 *
3402 * Prior to this fix, it was not possible to reliably save
3403 * a session making use of the --shm-path option, destroy it,
3404 * and load it again. This is because the creation of the
3405 * session would fail upon seeing the session's shm path
3406 * already in existence.
3407 *
3408 * Note that none of the error paths in the check for the
3409 * directory's existence return an error. This is normal
3410 * as there isn't much that can be done. The session will
3411 * be destroyed properly, except that we can't offer the
3412 * guarantee that the same session can be re-created.
3413 */
3414 current_completion_handler = &destroy_completion_handler.handler;
3415 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3416 session->shm_path,
3417 sizeof(destroy_completion_handler.shm_path));
3418 assert(!ret);
3419 }
3420
3421 /*
3422 * The session is destroyed. However, note that the command context
3423 * still holds a reference to the session, thus delaying its destruction
3424 * _at least_ up to the point when that reference is released.
3425 */
3426 session_destroy(session);
3427 if (reply_context) {
3428 reply_context->destruction_status = destruction_last_error;
3429 ret = session_add_destroy_notifier(session,
3430 cmd_destroy_session_reply,
3431 (void *) reply_context);
3432 if (ret) {
3433 ret = LTTNG_ERR_FATAL;
3434 goto end;
3435 } else {
3436 *sock_fd = -1;
3437 }
3438 }
3439 ret = LTTNG_OK;
3440 end:
3441 return ret;
3442 }
3443
3444 /*
3445 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3446 */
3447 int cmd_register_consumer(struct ltt_session *session,
3448 enum lttng_domain_type domain, const char *sock_path,
3449 struct consumer_data *cdata)
3450 {
3451 int ret, sock;
3452 struct consumer_socket *socket = NULL;
3453
3454 assert(session);
3455 assert(cdata);
3456 assert(sock_path);
3457
3458 switch (domain) {
3459 case LTTNG_DOMAIN_KERNEL:
3460 {
3461 struct ltt_kernel_session *ksess = session->kernel_session;
3462
3463 assert(ksess);
3464
3465 /* Can't register a consumer if there is already one */
3466 if (ksess->consumer_fds_sent != 0) {
3467 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3468 goto error;
3469 }
3470
3471 sock = lttcomm_connect_unix_sock(sock_path);
3472 if (sock < 0) {
3473 ret = LTTNG_ERR_CONNECT_FAIL;
3474 goto error;
3475 }
3476 cdata->cmd_sock = sock;
3477
3478 socket = consumer_allocate_socket(&cdata->cmd_sock);
3479 if (socket == NULL) {
3480 ret = close(sock);
3481 if (ret < 0) {
3482 PERROR("close register consumer");
3483 }
3484 cdata->cmd_sock = -1;
3485 ret = LTTNG_ERR_FATAL;
3486 goto error;
3487 }
3488
3489 socket->lock = zmalloc(sizeof(pthread_mutex_t));
3490 if (socket->lock == NULL) {
3491 PERROR("zmalloc pthread mutex");
3492 ret = LTTNG_ERR_FATAL;
3493 goto error;
3494 }
3495 pthread_mutex_init(socket->lock, NULL);
3496 socket->registered = 1;
3497
3498 rcu_read_lock();
3499 consumer_add_socket(socket, ksess->consumer);
3500 rcu_read_unlock();
3501
3502 pthread_mutex_lock(&cdata->pid_mutex);
3503 cdata->pid = -1;
3504 pthread_mutex_unlock(&cdata->pid_mutex);
3505
3506 break;
3507 }
3508 default:
3509 /* TODO: Userspace tracing */
3510 ret = LTTNG_ERR_UND;
3511 goto error;
3512 }
3513
3514 return LTTNG_OK;
3515
3516 error:
3517 if (socket) {
3518 consumer_destroy_socket(socket);
3519 }
3520 return ret;
3521 }
3522
3523 /*
3524 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3525 */
3526 ssize_t cmd_list_domains(struct ltt_session *session,
3527 struct lttng_domain **domains)
3528 {
3529 int ret, index = 0;
3530 ssize_t nb_dom = 0;
3531 struct agent *agt;
3532 struct lttng_ht_iter iter;
3533
3534 if (session->kernel_session != NULL) {
3535 DBG3("Listing domains found kernel domain");
3536 nb_dom++;
3537 }
3538
3539 if (session->ust_session != NULL) {
3540 DBG3("Listing domains found UST global domain");
3541 nb_dom++;
3542
3543 rcu_read_lock();
3544 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3545 agt, node.node) {
3546 if (agt->being_used) {
3547 nb_dom++;
3548 }
3549 }
3550 rcu_read_unlock();
3551 }
3552
3553 if (!nb_dom) {
3554 goto end;
3555 }
3556
3557 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3558 if (*domains == NULL) {
3559 ret = LTTNG_ERR_FATAL;
3560 goto error;
3561 }
3562
3563 if (session->kernel_session != NULL) {
3564 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3565
3566 /* Kernel session buffer type is always GLOBAL */
3567 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3568
3569 index++;
3570 }
3571
3572 if (session->ust_session != NULL) {
3573 (*domains)[index].type = LTTNG_DOMAIN_UST;
3574 (*domains)[index].buf_type = session->ust_session->buffer_type;
3575 index++;
3576
3577 rcu_read_lock();
3578 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3579 agt, node.node) {
3580 if (agt->being_used) {
3581 (*domains)[index].type = agt->domain;
3582 (*domains)[index].buf_type = session->ust_session->buffer_type;
3583 index++;
3584 }
3585 }
3586 rcu_read_unlock();
3587 }
3588 end:
3589 return nb_dom;
3590
3591 error:
3592 /* Return negative value to differentiate return code */
3593 return -ret;
3594 }
3595
3596
3597 /*
3598 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3599 */
3600 ssize_t cmd_list_channels(enum lttng_domain_type domain,
3601 struct ltt_session *session, struct lttng_channel **channels)
3602 {
3603 ssize_t nb_chan = 0, payload_size = 0, ret;
3604
3605 switch (domain) {
3606 case LTTNG_DOMAIN_KERNEL:
3607 if (session->kernel_session != NULL) {
3608 nb_chan = session->kernel_session->channel_count;
3609 }
3610 DBG3("Number of kernel channels %zd", nb_chan);
3611 if (nb_chan <= 0) {
3612 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
3613 goto end;
3614 }
3615 break;
3616 case LTTNG_DOMAIN_UST:
3617 if (session->ust_session != NULL) {
3618 rcu_read_lock();
3619 nb_chan = lttng_ht_get_count(
3620 session->ust_session->domain_global.channels);
3621 rcu_read_unlock();
3622 }
3623 DBG3("Number of UST global channels %zd", nb_chan);
3624 if (nb_chan < 0) {
3625 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
3626 goto end;
3627 }
3628 break;
3629 default:
3630 ret = -LTTNG_ERR_UND;
3631 goto end;
3632 }
3633
3634 if (nb_chan > 0) {
3635 const size_t channel_size = sizeof(struct lttng_channel) +
3636 sizeof(struct lttng_channel_extended);
3637 struct lttng_channel_extended *channel_exts;
3638
3639 payload_size = nb_chan * channel_size;
3640 *channels = zmalloc(payload_size);
3641 if (*channels == NULL) {
3642 ret = -LTTNG_ERR_FATAL;
3643 goto end;
3644 }
3645
3646 channel_exts = ((void *) *channels) +
3647 (nb_chan * sizeof(struct lttng_channel));
3648 ret = list_lttng_channels(domain, session, *channels, channel_exts);
3649 if (ret != LTTNG_OK) {
3650 free(*channels);
3651 *channels = NULL;
3652 goto end;
3653 }
3654 } else {
3655 *channels = NULL;
3656 }
3657
3658 ret = payload_size;
3659 end:
3660 return ret;
3661 }
3662
3663 /*
3664 * Command LTTNG_LIST_EVENTS processed by the client thread.
3665 */
3666 ssize_t cmd_list_events(enum lttng_domain_type domain,
3667 struct ltt_session *session, char *channel_name,
3668 struct lttng_event **events, size_t *total_size)
3669 {
3670 int ret = 0;
3671 ssize_t nb_event = 0;
3672
3673 switch (domain) {
3674 case LTTNG_DOMAIN_KERNEL:
3675 if (session->kernel_session != NULL) {
3676 nb_event = list_lttng_kernel_events(channel_name,
3677 session->kernel_session, events,
3678 total_size);
3679 }
3680 break;
3681 case LTTNG_DOMAIN_UST:
3682 {
3683 if (session->ust_session != NULL) {
3684 nb_event = list_lttng_ust_global_events(channel_name,
3685 &session->ust_session->domain_global, events,
3686 total_size);
3687 }
3688 break;
3689 }
3690 case LTTNG_DOMAIN_LOG4J:
3691 case LTTNG_DOMAIN_JUL:
3692 case LTTNG_DOMAIN_PYTHON:
3693 if (session->ust_session) {
3694 struct lttng_ht_iter iter;
3695 struct agent *agt;
3696
3697 rcu_read_lock();
3698 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3699 &iter.iter, agt, node.node) {
3700 if (agt->domain == domain) {
3701 nb_event = list_lttng_agent_events(
3702 agt, events,
3703 total_size);
3704 break;
3705 }
3706 }
3707 rcu_read_unlock();
3708 }
3709 break;
3710 default:
3711 ret = LTTNG_ERR_UND;
3712 goto error;
3713 }
3714
3715 return nb_event;
3716
3717 error:
3718 /* Return negative value to differentiate return code */
3719 return -ret;
3720 }
3721
3722 /*
3723 * Using the session list, filled a lttng_session array to send back to the
3724 * client for session listing.
3725 *
3726 * The session list lock MUST be acquired before calling this function. Use
3727 * session_lock_list() and session_unlock_list().
3728 */
3729 void cmd_list_lttng_sessions(struct lttng_session *sessions,
3730 size_t session_count, uid_t uid, gid_t gid)
3731 {
3732 int ret;
3733 unsigned int i = 0;
3734 struct ltt_session *session;
3735 struct ltt_session_list *list = session_get_list();
3736 struct lttng_session_extended *extended =
3737 (typeof(extended)) (&sessions[session_count]);
3738
3739 DBG("Getting all available session for UID %d GID %d",
3740 uid, gid);
3741 /*
3742 * Iterate over session list and append data after the control struct in
3743 * the buffer.
3744 */
3745 cds_list_for_each_entry(session, &list->head, list) {
3746 if (!session_get(session)) {
3747 continue;
3748 }
3749 /*
3750 * Only list the sessions the user can control.
3751 */
3752 if (!session_access_ok(session, uid, gid) ||
3753 session->destroyed) {
3754 session_put(session);
3755 continue;
3756 }
3757
3758 struct ltt_kernel_session *ksess = session->kernel_session;
3759 struct ltt_ust_session *usess = session->ust_session;
3760
3761 if (session->consumer->type == CONSUMER_DST_NET ||
3762 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3763 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3764 ret = build_network_session_path(sessions[i].path,
3765 sizeof(sessions[i].path), session);
3766 } else {
3767 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3768 session->consumer->dst.session_root_path);
3769 }
3770 if (ret < 0) {
3771 PERROR("snprintf session path");
3772 session_put(session);
3773 continue;
3774 }
3775
3776 strncpy(sessions[i].name, session->name, NAME_MAX);
3777 sessions[i].name[NAME_MAX - 1] = '\0';
3778 sessions[i].enabled = session->active;
3779 sessions[i].snapshot_mode = session->snapshot_mode;
3780 sessions[i].live_timer_interval = session->live_timer;
3781 extended[i].creation_time.value = (uint64_t) session->creation_time;
3782 extended[i].creation_time.is_set = 1;
3783 i++;
3784 session_put(session);
3785 }
3786 }
3787
3788 /*
3789 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3790 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3791 */
3792 int cmd_data_pending(struct ltt_session *session)
3793 {
3794 int ret;
3795 struct ltt_kernel_session *ksess = session->kernel_session;
3796 struct ltt_ust_session *usess = session->ust_session;
3797
3798 assert(session);
3799
3800 DBG("Data pending for session %s", session->name);
3801
3802 /* Session MUST be stopped to ask for data availability. */
3803 if (session->active) {
3804 ret = LTTNG_ERR_SESSION_STARTED;
3805 goto error;
3806 } else {
3807 /*
3808 * If stopped, just make sure we've started before else the above call
3809 * will always send that there is data pending.
3810 *
3811 * The consumer assumes that when the data pending command is received,
3812 * the trace has been started before or else no output data is written
3813 * by the streams which is a condition for data pending. So, this is
3814 * *VERY* important that we don't ask the consumer before a start
3815 * trace.
3816 */
3817 if (!session->has_been_started) {
3818 ret = 0;
3819 goto error;
3820 }
3821 }
3822
3823 /* A rotation is still pending, we have to wait. */
3824 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
3825 DBG("Rotate still pending for session %s", session->name);
3826 ret = 1;
3827 goto error;
3828 }
3829
3830 if (ksess && ksess->consumer) {
3831 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3832 if (ret == 1) {
3833 /* Data is still being extracted for the kernel. */
3834 goto error;
3835 }
3836 }
3837
3838 if (usess && usess->consumer) {
3839 ret = consumer_is_data_pending(usess->id, usess->consumer);
3840 if (ret == 1) {
3841 /* Data is still being extracted for the kernel. */
3842 goto error;
3843 }
3844 }
3845
3846 /* Data is ready to be read by a viewer */
3847 ret = 0;
3848
3849 error:
3850 return ret;
3851 }
3852
3853 /*
3854 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3855 *
3856 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3857 */
3858 int cmd_snapshot_add_output(struct ltt_session *session,
3859 const struct lttng_snapshot_output *output, uint32_t *id)
3860 {
3861 int ret;
3862 struct snapshot_output *new_output;
3863
3864 assert(session);
3865 assert(output);
3866
3867 DBG("Cmd snapshot add output for session %s", session->name);
3868
3869 /*
3870 * Can't create an output if the session is not set in no-output mode.
3871 */
3872 if (session->output_traces) {
3873 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3874 goto error;
3875 }
3876
3877 if (session->has_non_mmap_channel) {
3878 ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
3879 goto error;
3880 }
3881
3882 /* Only one output is allowed until we have the "tee" feature. */
3883 if (session->snapshot.nb_output == 1) {
3884 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3885 goto error;
3886 }
3887
3888 new_output = snapshot_output_alloc();
3889 if (!new_output) {
3890 ret = LTTNG_ERR_NOMEM;
3891 goto error;
3892 }
3893
3894 ret = snapshot_output_init(session, output->max_size, output->name,
3895 output->ctrl_url, output->data_url, session->consumer, new_output,
3896 &session->snapshot);
3897 if (ret < 0) {
3898 if (ret == -ENOMEM) {
3899 ret = LTTNG_ERR_NOMEM;
3900 } else {
3901 ret = LTTNG_ERR_INVALID;
3902 }
3903 goto free_error;
3904 }
3905
3906 rcu_read_lock();
3907 snapshot_add_output(&session->snapshot, new_output);
3908 if (id) {
3909 *id = new_output->id;
3910 }
3911 rcu_read_unlock();
3912
3913 return LTTNG_OK;
3914
3915 free_error:
3916 snapshot_output_destroy(new_output);
3917 error:
3918 return ret;
3919 }
3920
3921 /*
3922 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3923 *
3924 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3925 */
3926 int cmd_snapshot_del_output(struct ltt_session *session,
3927 const struct lttng_snapshot_output *output)
3928 {
3929 int ret;
3930 struct snapshot_output *sout = NULL;
3931
3932 assert(session);
3933 assert(output);
3934
3935 rcu_read_lock();
3936
3937 /*
3938 * Permission denied to create an output if the session is not
3939 * set in no output mode.
3940 */
3941 if (session->output_traces) {
3942 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3943 goto error;
3944 }
3945
3946 if (output->id) {
3947 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
3948 session->name);
3949 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
3950 } else if (*output->name != '\0') {
3951 DBG("Cmd snapshot del output name %s for session %s", output->name,
3952 session->name);
3953 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
3954 }
3955 if (!sout) {
3956 ret = LTTNG_ERR_INVALID;
3957 goto error;
3958 }
3959
3960 snapshot_delete_output(&session->snapshot, sout);
3961 snapshot_output_destroy(sout);
3962 ret = LTTNG_OK;
3963
3964 error:
3965 rcu_read_unlock();
3966 return ret;
3967 }
3968
3969 /*
3970 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
3971 *
3972 * If no output is available, outputs is untouched and 0 is returned.
3973 *
3974 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
3975 */
3976 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
3977 struct lttng_snapshot_output **outputs)
3978 {
3979 int ret, idx = 0;
3980 struct lttng_snapshot_output *list = NULL;
3981 struct lttng_ht_iter iter;
3982 struct snapshot_output *output;
3983
3984 assert(session);
3985 assert(outputs);
3986
3987 DBG("Cmd snapshot list outputs for session %s", session->name);
3988
3989 /*
3990 * Permission denied to create an output if the session is not
3991 * set in no output mode.
3992 */
3993 if (session->output_traces) {
3994 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3995 goto end;
3996 }
3997
3998 if (session->snapshot.nb_output == 0) {
3999 ret = 0;
4000 goto end;
4001 }
4002
4003 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
4004 if (!list) {
4005 ret = -LTTNG_ERR_NOMEM;
4006 goto end;
4007 }
4008
4009 /* Copy list from session to the new list object. */
4010 rcu_read_lock();
4011 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
4012 output, node.node) {
4013 assert(output->consumer);
4014 list[idx].id = output->id;
4015 list[idx].max_size = output->max_size;
4016 if (lttng_strncpy(list[idx].name, output->name,
4017 sizeof(list[idx].name))) {
4018 ret = -LTTNG_ERR_INVALID;
4019 goto error;
4020 }
4021 if (output->consumer->type == CONSUMER_DST_LOCAL) {
4022 if (lttng_strncpy(list[idx].ctrl_url,
4023 output->consumer->dst.session_root_path,
4024 sizeof(list[idx].ctrl_url))) {
4025 ret = -LTTNG_ERR_INVALID;
4026 goto error;
4027 }
4028 } else {
4029 /* Control URI. */
4030 ret = uri_to_str_url(&output->consumer->dst.net.control,
4031 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
4032 if (ret < 0) {
4033 ret = -LTTNG_ERR_NOMEM;
4034 goto error;
4035 }
4036
4037 /* Data URI. */
4038 ret = uri_to_str_url(&output->consumer->dst.net.data,
4039 list[idx].data_url, sizeof(list[idx].data_url));
4040 if (ret < 0) {
4041 ret = -LTTNG_ERR_NOMEM;
4042 goto error;
4043 }
4044 }
4045 idx++;
4046 }
4047
4048 *outputs = list;
4049 list = NULL;
4050 ret = session->snapshot.nb_output;
4051 error:
4052 rcu_read_unlock();
4053 free(list);
4054 end:
4055 return ret;
4056 }
4057
4058 /*
4059 * Check if we can regenerate the metadata for this session.
4060 * Only kernel, UST per-uid and non-live sessions are supported.
4061 *
4062 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
4063 */
4064 static
4065 int check_regenerate_metadata_support(struct ltt_session *session)
4066 {
4067 int ret;
4068
4069 assert(session);
4070
4071 if (session->live_timer != 0) {
4072 ret = LTTNG_ERR_LIVE_SESSION;
4073 goto end;
4074 }
4075 if (!session->active) {
4076 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4077 goto end;
4078 }
4079 if (session->ust_session) {
4080 switch (session->ust_session->buffer_type) {
4081 case LTTNG_BUFFER_PER_UID:
4082 break;
4083 case LTTNG_BUFFER_PER_PID:
4084 ret = LTTNG_ERR_PER_PID_SESSION;
4085 goto end;
4086 default:
4087 assert(0);
4088 ret = LTTNG_ERR_UNK;
4089 goto end;
4090 }
4091 }
4092 if (session->consumer->type == CONSUMER_DST_NET &&
4093 session->consumer->relay_minor_version < 8) {
4094 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
4095 goto end;
4096 }
4097 ret = 0;
4098
4099 end:
4100 return ret;
4101 }
4102
4103 static
4104 int clear_metadata_file(int fd)
4105 {
4106 int ret;
4107 off_t lseek_ret;
4108
4109 lseek_ret = lseek(fd, 0, SEEK_SET);
4110 if (lseek_ret < 0) {
4111 PERROR("lseek");
4112 ret = -1;
4113 goto end;
4114 }
4115
4116 ret = ftruncate(fd, 0);
4117 if (ret < 0) {
4118 PERROR("ftruncate");
4119 goto end;
4120 }
4121
4122 end:
4123 return ret;
4124 }
4125
4126 static
4127 int ust_regenerate_metadata(struct ltt_ust_session *usess)
4128 {
4129 int ret = 0;
4130 struct buffer_reg_uid *uid_reg = NULL;
4131 struct buffer_reg_session *session_reg = NULL;
4132
4133 rcu_read_lock();
4134 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
4135 struct ust_registry_session *registry;
4136 struct ust_registry_channel *chan;
4137 struct lttng_ht_iter iter_chan;
4138
4139 session_reg = uid_reg->registry;
4140 registry = session_reg->reg.ust;
4141
4142 pthread_mutex_lock(&registry->lock);
4143 registry->metadata_len_sent = 0;
4144 memset(registry->metadata, 0, registry->metadata_alloc_len);
4145 registry->metadata_len = 0;
4146 registry->metadata_version++;
4147 if (registry->metadata_fd > 0) {
4148 /* Clear the metadata file's content. */
4149 ret = clear_metadata_file(registry->metadata_fd);
4150 if (ret) {
4151 pthread_mutex_unlock(&registry->lock);
4152 goto end;
4153 }
4154 }
4155
4156 ret = ust_metadata_session_statedump(registry, NULL,
4157 registry->major, registry->minor);
4158 if (ret) {
4159 pthread_mutex_unlock(&registry->lock);
4160 ERR("Failed to generate session metadata (err = %d)",
4161 ret);
4162 goto end;
4163 }
4164 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
4165 chan, node.node) {
4166 struct ust_registry_event *event;
4167 struct lttng_ht_iter iter_event;
4168
4169 ret = ust_metadata_channel_statedump(registry, chan);
4170 if (ret) {
4171 pthread_mutex_unlock(&registry->lock);
4172 ERR("Failed to generate channel metadata "
4173 "(err = %d)", ret);
4174 goto end;
4175 }
4176 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
4177 event, node.node) {
4178 ret = ust_metadata_event_statedump(registry,
4179 chan, event);
4180 if (ret) {
4181 pthread_mutex_unlock(&registry->lock);
4182 ERR("Failed to generate event metadata "
4183 "(err = %d)", ret);
4184 goto end;
4185 }
4186 }
4187 }
4188 pthread_mutex_unlock(&registry->lock);
4189 }
4190
4191 end:
4192 rcu_read_unlock();
4193 return ret;
4194 }
4195
4196 /*
4197 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
4198 *
4199 * Ask the consumer to truncate the existing metadata file(s) and
4200 * then regenerate the metadata. Live and per-pid sessions are not
4201 * supported and return an error.
4202 *
4203 * Return 0 on success or else a LTTNG_ERR code.
4204 */
4205 int cmd_regenerate_metadata(struct ltt_session *session)
4206 {
4207 int ret;
4208
4209 assert(session);
4210
4211 ret = check_regenerate_metadata_support(session);
4212 if (ret) {
4213 goto end;
4214 }
4215
4216 if (session->kernel_session) {
4217 ret = kernctl_session_regenerate_metadata(
4218 session->kernel_session->fd);
4219 if (ret < 0) {
4220 ERR("Failed to regenerate the kernel metadata");
4221 goto end;
4222 }
4223 }
4224
4225 if (session->ust_session) {
4226 ret = ust_regenerate_metadata(session->ust_session);
4227 if (ret < 0) {
4228 ERR("Failed to regenerate the UST metadata");
4229 goto end;
4230 }
4231 }
4232 DBG("Cmd metadata regenerate for session %s", session->name);
4233 ret = LTTNG_OK;
4234
4235 end:
4236 return ret;
4237 }
4238
4239 /*
4240 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
4241 *
4242 * Ask the tracer to regenerate a new statedump.
4243 *
4244 * Return 0 on success or else a LTTNG_ERR code.
4245 */
4246 int cmd_regenerate_statedump(struct ltt_session *session)
4247 {
4248 int ret;
4249
4250 assert(session);
4251
4252 if (!session->active) {
4253 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4254 goto end;
4255 }
4256
4257 if (session->kernel_session) {
4258 ret = kernctl_session_regenerate_statedump(
4259 session->kernel_session->fd);
4260 /*
4261 * Currently, the statedump in kernel can only fail if out
4262 * of memory.
4263 */
4264 if (ret < 0) {
4265 if (ret == -ENOMEM) {
4266 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
4267 } else {
4268 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4269 }
4270 ERR("Failed to regenerate the kernel statedump");
4271 goto end;
4272 }
4273 }
4274
4275 if (session->ust_session) {
4276 ret = ust_app_regenerate_statedump_all(session->ust_session);
4277 /*
4278 * Currently, the statedump in UST always returns 0.
4279 */
4280 if (ret < 0) {
4281 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4282 ERR("Failed to regenerate the UST statedump");
4283 goto end;
4284 }
4285 }
4286 DBG("Cmd regenerate statedump for session %s", session->name);
4287 ret = LTTNG_OK;
4288
4289 end:
4290 return ret;
4291 }
4292
4293 int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
4294 struct notification_thread_handle *notification_thread)
4295 {
4296 int ret;
4297 size_t trigger_len;
4298 ssize_t sock_recv_len;
4299 struct lttng_trigger *trigger = NULL;
4300 struct lttng_buffer_view view;
4301 struct lttng_dynamic_buffer trigger_buffer;
4302
4303 lttng_dynamic_buffer_init(&trigger_buffer);
4304 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4305 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4306 if (ret) {
4307 ret = LTTNG_ERR_NOMEM;
4308 goto end;
4309 }
4310
4311 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4312 trigger_len);
4313 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4314 ERR("Failed to receive \"register trigger\" command payload");
4315 /* TODO: should this be a new error enum ? */
4316 ret = LTTNG_ERR_INVALID_TRIGGER;
4317 goto end;
4318 }
4319
4320 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4321 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4322 trigger_len) {
4323 ERR("Invalid trigger payload received in \"register trigger\" command");
4324 ret = LTTNG_ERR_INVALID_TRIGGER;
4325 goto end;
4326 }
4327
4328 ret = notification_thread_command_register_trigger(notification_thread,
4329 trigger);
4330 /* Ownership of trigger was transferred. */
4331 trigger = NULL;
4332 end:
4333 lttng_trigger_destroy(trigger);
4334 lttng_dynamic_buffer_reset(&trigger_buffer);
4335 return ret;
4336 }
4337
4338 int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
4339 struct notification_thread_handle *notification_thread)
4340 {
4341 int ret;
4342 size_t trigger_len;
4343 ssize_t sock_recv_len;
4344 struct lttng_trigger *trigger = NULL;
4345 struct lttng_buffer_view view;
4346 struct lttng_dynamic_buffer trigger_buffer;
4347
4348 lttng_dynamic_buffer_init(&trigger_buffer);
4349 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4350 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4351 if (ret) {
4352 ret = LTTNG_ERR_NOMEM;
4353 goto end;
4354 }
4355
4356 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4357 trigger_len);
4358 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4359 ERR("Failed to receive \"unregister trigger\" command payload");
4360 /* TODO: should this be a new error enum ? */
4361 ret = LTTNG_ERR_INVALID_TRIGGER;
4362 goto end;
4363 }
4364
4365 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4366 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4367 trigger_len) {
4368 ERR("Invalid trigger payload received in \"unregister trigger\" command");
4369 ret = LTTNG_ERR_INVALID_TRIGGER;
4370 goto end;
4371 }
4372
4373 ret = notification_thread_command_unregister_trigger(notification_thread,
4374 trigger);
4375 end:
4376 lttng_trigger_destroy(trigger);
4377 lttng_dynamic_buffer_reset(&trigger_buffer);
4378 return ret;
4379 }
4380
4381 /*
4382 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4383 * snapshot output is *not* set with a remote destination.
4384 *
4385 * Return LTTNG_OK on success or a LTTNG_ERR code.
4386 */
4387 static enum lttng_error_code set_relayd_for_snapshot(
4388 struct consumer_output *output,
4389 const struct ltt_session *session)
4390 {
4391 enum lttng_error_code status = LTTNG_OK;
4392 struct lttng_ht_iter iter;
4393 struct consumer_socket *socket;
4394 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
4395 const char *base_path;
4396
4397 assert(output);
4398 assert(session);
4399
4400 DBG2("Set relayd object from snapshot output");
4401
4402 if (session->current_trace_chunk) {
4403 enum lttng_trace_chunk_status chunk_status =
4404 lttng_trace_chunk_get_id(
4405 session->current_trace_chunk,
4406 &current_chunk_id.value);
4407
4408 if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK) {
4409 current_chunk_id.is_set = true;
4410 } else {
4411 ERR("Failed to get current trace chunk id");
4412 status = LTTNG_ERR_UNK;
4413 goto error;
4414 }
4415 }
4416
4417 /* Ignore if snapshot consumer output is not network. */
4418 if (output->type != CONSUMER_DST_NET) {
4419 goto error;
4420 }
4421
4422 /*
4423 * The snapshot record URI base path overrides the session
4424 * base path.
4425 */
4426 if (output->dst.net.control.subdir[0] != '\0') {
4427 base_path = output->dst.net.control.subdir;
4428 } else {
4429 base_path = session->base_path;
4430 }
4431
4432 /*
4433 * For each consumer socket, create and send the relayd object of the
4434 * snapshot output.
4435 */
4436 rcu_read_lock();
4437 cds_lfht_for_each_entry(output->socks->ht, &iter.iter,
4438 socket, node.node) {
4439 pthread_mutex_lock(socket->lock);
4440 status = send_consumer_relayd_sockets(0, session->id,
4441 output, socket,
4442 session->name, session->hostname,
4443 base_path,
4444 session->live_timer,
4445 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
4446 session->creation_time,
4447 session->name_contains_creation_time);
4448 pthread_mutex_unlock(socket->lock);
4449 if (status != LTTNG_OK) {
4450 rcu_read_unlock();
4451 goto error;
4452 }
4453 }
4454 rcu_read_unlock();
4455
4456 error:
4457 return status;
4458 }
4459
4460 /*
4461 * Record a kernel snapshot.
4462 *
4463 * Return LTTNG_OK on success or a LTTNG_ERR code.
4464 */
4465 static enum lttng_error_code record_kernel_snapshot(
4466 struct ltt_kernel_session *ksess,
4467 const struct consumer_output *output,
4468 const struct ltt_session *session,
4469 int wait, uint64_t nb_packets_per_stream)
4470 {
4471 enum lttng_error_code status;
4472
4473 assert(ksess);
4474 assert(output);
4475 assert(session);
4476
4477 status = kernel_snapshot_record(
4478 ksess, output, wait, nb_packets_per_stream);
4479 return status;
4480 }
4481
4482 /*
4483 * Record a UST snapshot.
4484 *
4485 * Returns LTTNG_OK on success or a LTTNG_ERR error code.
4486 */
4487 static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
4488 const struct consumer_output *output,
4489 const struct ltt_session *session,
4490 int wait, uint64_t nb_packets_per_stream)
4491 {
4492 enum lttng_error_code status;
4493
4494 assert(usess);
4495 assert(output);
4496 assert(session);
4497
4498 status = ust_app_snapshot_record(
4499 usess, output, wait, nb_packets_per_stream);
4500 return status;
4501 }
4502
4503 static
4504 uint64_t get_session_size_one_more_packet_per_stream(
4505 const struct ltt_session *session, uint64_t cur_nr_packets)
4506 {
4507 uint64_t tot_size = 0;
4508
4509 if (session->kernel_session) {
4510 struct ltt_kernel_channel *chan;
4511 const struct ltt_kernel_session *ksess =
4512 session->kernel_session;
4513
4514 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
4515 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
4516 /*
4517 * Don't take channel into account if we
4518 * already grab all its packets.
4519 */
4520 continue;
4521 }
4522 tot_size += chan->channel->attr.subbuf_size
4523 * chan->stream_count;
4524 }
4525 }
4526
4527 if (session->ust_session) {
4528 const struct ltt_ust_session *usess = session->ust_session;
4529
4530 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
4531 cur_nr_packets);
4532 }
4533
4534 return tot_size;
4535 }
4536
4537 /*
4538 * Calculate the number of packets we can grab from each stream that
4539 * fits within the overall snapshot max size.
4540 *
4541 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
4542 * the number of packets per stream.
4543 *
4544 * TODO: this approach is not perfect: we consider the worse case
4545 * (packet filling the sub-buffers) as an upper bound, but we could do
4546 * better if we do this calculation while we actually grab the packet
4547 * content: we would know how much padding we don't actually store into
4548 * the file.
4549 *
4550 * This algorithm is currently bounded by the number of packets per
4551 * stream.
4552 *
4553 * Since we call this algorithm before actually grabbing the data, it's
4554 * an approximation: for instance, applications could appear/disappear
4555 * in between this call and actually grabbing data.
4556 */
4557 static
4558 int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
4559 uint64_t max_size)
4560 {
4561 int64_t size_left;
4562 uint64_t cur_nb_packets = 0;
4563
4564 if (!max_size) {
4565 return 0; /* Infinite */
4566 }
4567
4568 size_left = max_size;
4569 for (;;) {
4570 uint64_t one_more_packet_tot_size;
4571
4572 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(
4573 session, cur_nb_packets);
4574 if (!one_more_packet_tot_size) {
4575 /* We are already grabbing all packets. */
4576 break;
4577 }
4578 size_left -= one_more_packet_tot_size;
4579 if (size_left < 0) {
4580 break;
4581 }
4582 cur_nb_packets++;
4583 }
4584 if (!cur_nb_packets) {
4585 /* Not enough room to grab one packet of each stream, error. */
4586 return -1;
4587 }
4588 return cur_nb_packets;
4589 }
4590
4591 static
4592 enum lttng_error_code snapshot_record(struct ltt_session *session,
4593 const struct snapshot_output *snapshot_output, int wait)
4594 {
4595 int64_t nb_packets_per_stream;
4596 char snapshot_chunk_name[LTTNG_NAME_MAX];
4597 int ret;
4598 enum lttng_error_code ret_code = LTTNG_OK;
4599 struct lttng_trace_chunk *snapshot_trace_chunk;
4600 struct consumer_output *original_ust_consumer_output = NULL;
4601 struct consumer_output *original_kernel_consumer_output = NULL;
4602 struct consumer_output *snapshot_ust_consumer_output = NULL;
4603 struct consumer_output *snapshot_kernel_consumer_output = NULL;
4604
4605 ret = snprintf(snapshot_chunk_name, sizeof(snapshot_chunk_name),
4606 "%s-%s-%" PRIu64,
4607 snapshot_output->name,
4608 snapshot_output->datetime,
4609 snapshot_output->nb_snapshot);
4610 if (ret < 0 || ret >= sizeof(snapshot_chunk_name)) {
4611 ERR("Failed to format snapshot name");
4612 ret_code = LTTNG_ERR_INVALID;
4613 goto error;
4614 }
4615 DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
4616 snapshot_output->name, session->name,
4617 snapshot_chunk_name);
4618 if (!session->kernel_session && !session->ust_session) {
4619 ERR("Failed to record snapshot as no channels exist");
4620 ret_code = LTTNG_ERR_NO_CHANNEL;
4621 goto error;
4622 }
4623
4624 if (session->kernel_session) {
4625 original_kernel_consumer_output =
4626 session->kernel_session->consumer;
4627 snapshot_kernel_consumer_output =
4628 consumer_copy_output(snapshot_output->consumer);
4629 strcpy(snapshot_kernel_consumer_output->chunk_path,
4630 snapshot_chunk_name);
4631 ret = consumer_copy_sockets(snapshot_kernel_consumer_output,
4632 original_kernel_consumer_output);
4633 if (ret < 0) {
4634 ERR("Failed to copy consumer sockets from snapshot output configuration");
4635 ret_code = LTTNG_ERR_NOMEM;
4636 goto error;
4637 }
4638 ret_code = set_relayd_for_snapshot(
4639 snapshot_kernel_consumer_output, session);
4640 if (ret_code != LTTNG_OK) {
4641 ERR("Failed to setup relay daemon for kernel tracer snapshot");
4642 goto error;
4643 }
4644 session->kernel_session->consumer =
4645 snapshot_kernel_consumer_output;
4646 }
4647 if (session->ust_session) {
4648 original_ust_consumer_output = session->ust_session->consumer;
4649 snapshot_ust_consumer_output =
4650 consumer_copy_output(snapshot_output->consumer);
4651 strcpy(snapshot_ust_consumer_output->chunk_path,
4652 snapshot_chunk_name);
4653 ret = consumer_copy_sockets(snapshot_ust_consumer_output,
4654 original_ust_consumer_output);
4655 if (ret < 0) {
4656 ERR("Failed to copy consumer sockets from snapshot output configuration");
4657 ret_code = LTTNG_ERR_NOMEM;
4658 goto error;
4659 }
4660 ret_code = set_relayd_for_snapshot(
4661 snapshot_ust_consumer_output, session);
4662 if (ret_code != LTTNG_OK) {
4663 ERR("Failed to setup relay daemon for userspace tracer snapshot");
4664 goto error;
4665 }
4666 session->ust_session->consumer =
4667 snapshot_ust_consumer_output;
4668 }
4669
4670 snapshot_trace_chunk = session_create_new_trace_chunk(session,
4671 snapshot_kernel_consumer_output ?:
4672 snapshot_ust_consumer_output,
4673 consumer_output_get_base_path(
4674 snapshot_output->consumer),
4675 snapshot_chunk_name);
4676 if (!snapshot_trace_chunk) {
4677 ERR("Failed to create temporary trace chunk to record a snapshot of session \"%s\"",
4678 session->name);
4679 ret_code = LTTNG_ERR_CREATE_DIR_FAIL;
4680 goto error;
4681 }
4682 assert(!session->current_trace_chunk);
4683 ret = session_set_trace_chunk(session, snapshot_trace_chunk, NULL);
4684 lttng_trace_chunk_put(snapshot_trace_chunk);
4685 snapshot_trace_chunk = NULL;
4686 if (ret) {
4687 ERR("Failed to set temporary trace chunk to record a snapshot of session \"%s\"",
4688 session->name);
4689 ret_code = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
4690 goto error;
4691 }
4692
4693 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
4694 snapshot_output->max_size);
4695 if (nb_packets_per_stream < 0) {
4696 ret_code = LTTNG_ERR_MAX_SIZE_INVALID;
4697 goto error;
4698 }
4699
4700 if (session->kernel_session) {
4701 ret_code = record_kernel_snapshot(session->kernel_session,
4702 snapshot_kernel_consumer_output, session,
4703 wait, nb_packets_per_stream);
4704 if (ret_code != LTTNG_OK) {
4705 goto error;
4706 }
4707 }
4708
4709 if (session->ust_session) {
4710 ret_code = record_ust_snapshot(session->ust_session,
4711 snapshot_ust_consumer_output, session,
4712 wait, nb_packets_per_stream);
4713 if (ret_code != LTTNG_OK) {
4714 goto error;
4715 }
4716 }
4717
4718 if (session_close_trace_chunk(session, session->current_trace_chunk,
4719 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION, NULL)) {
4720 /*
4721 * Don't goto end; make sure the chunk is closed for the session
4722 * to allow future snapshots.
4723 */
4724 ERR("Failed to close snapshot trace chunk of session \"%s\"",
4725 session->name);
4726 ret_code = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
4727 }
4728 if (session_set_trace_chunk(session, NULL, NULL)) {
4729 ERR("Failed to release the current trace chunk of session \"%s\"",
4730 session->name);
4731 ret_code = LTTNG_ERR_UNK;
4732 }
4733 error:
4734 if (original_ust_consumer_output) {
4735 session->ust_session->consumer = original_ust_consumer_output;
4736 }
4737 if (original_kernel_consumer_output) {
4738 session->kernel_session->consumer =
4739 original_kernel_consumer_output;
4740 }
4741 consumer_output_put(snapshot_ust_consumer_output);
4742 consumer_output_put(snapshot_kernel_consumer_output);
4743 return ret_code;
4744 }
4745
4746 /*
4747 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
4748 *
4749 * The wait parameter is ignored so this call always wait for the snapshot to
4750 * complete before returning.
4751 *
4752 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4753 */
4754 int cmd_snapshot_record(struct ltt_session *session,
4755 const struct lttng_snapshot_output *output, int wait)
4756 {
4757 enum lttng_error_code cmd_ret = LTTNG_OK;
4758 int ret;
4759 unsigned int snapshot_success = 0;
4760 char datetime[16];
4761 struct snapshot_output *tmp_output = NULL;
4762
4763 assert(session);
4764 assert(output);
4765
4766 DBG("Cmd snapshot record for session %s", session->name);
4767
4768 /* Get the datetime for the snapshot output directory. */
4769 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
4770 sizeof(datetime));
4771 if (!ret) {
4772 cmd_ret = LTTNG_ERR_INVALID;
4773 goto error;
4774 }
4775
4776 /*
4777 * Permission denied to create an output if the session is not
4778 * set in no output mode.
4779 */
4780 if (session->output_traces) {
4781 cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4782 goto error;
4783 }
4784
4785 /* The session needs to be started at least once. */
4786 if (!session->has_been_started) {
4787 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4788 goto error;
4789 }
4790
4791 /* Use temporary output for the session. */
4792 if (*output->ctrl_url != '\0') {
4793 tmp_output = snapshot_output_alloc();
4794 if (!tmp_output) {
4795 cmd_ret = LTTNG_ERR_NOMEM;
4796 goto error;
4797 }
4798
4799 ret = snapshot_output_init(session, output->max_size,
4800 output->name,
4801 output->ctrl_url, output->data_url,
4802 session->consumer,
4803 tmp_output, NULL);
4804 if (ret < 0) {
4805 if (ret == -ENOMEM) {
4806 cmd_ret = LTTNG_ERR_NOMEM;
4807 } else {
4808 cmd_ret = LTTNG_ERR_INVALID;
4809 }
4810 goto error;
4811 }
4812 /* Use the global session count for the temporary snapshot. */
4813 tmp_output->nb_snapshot = session->snapshot.nb_snapshot;
4814
4815 /* Use the global datetime */
4816 memcpy(tmp_output->datetime, datetime, sizeof(datetime));
4817 cmd_ret = snapshot_record(session, tmp_output, wait);
4818 if (cmd_ret != LTTNG_OK) {
4819 goto error;
4820 }
4821 snapshot_success = 1;
4822 } else {
4823 struct snapshot_output *sout;
4824 struct lttng_ht_iter iter;
4825
4826 rcu_read_lock();
4827 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
4828 &iter.iter, sout, node.node) {
4829 struct snapshot_output output_copy;
4830
4831 /*
4832 * Make a local copy of the output and override output
4833 * parameters with those provided as part of the
4834 * command.
4835 */
4836 memcpy(&output_copy, sout, sizeof(output_copy));
4837
4838 if (output->max_size != (uint64_t) -1ULL) {
4839 output_copy.max_size = output->max_size;
4840 }
4841
4842 output_copy.nb_snapshot = session->snapshot.nb_snapshot;
4843 memcpy(output_copy.datetime, datetime,
4844 sizeof(datetime));
4845
4846 /* Use temporary name. */
4847 if (*output->name != '\0') {
4848 if (lttng_strncpy(output_copy.name,
4849 output->name,
4850 sizeof(output_copy.name))) {
4851 cmd_ret = LTTNG_ERR_INVALID;
4852 rcu_read_unlock();
4853 goto error;
4854 }
4855 }
4856
4857 cmd_ret = snapshot_record(session, &output_copy, wait);
4858 if (cmd_ret != LTTNG_OK) {
4859 rcu_read_unlock();
4860 goto error;
4861 }
4862 snapshot_success = 1;
4863 }
4864 rcu_read_unlock();
4865 }
4866
4867 if (snapshot_success) {
4868 session->snapshot.nb_snapshot++;
4869 } else {
4870 cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
4871 }
4872
4873 error:
4874 if (tmp_output) {
4875 snapshot_output_destroy(tmp_output);
4876 }
4877 return cmd_ret;
4878 }
4879
4880 /*
4881 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
4882 */
4883 int cmd_set_session_shm_path(struct ltt_session *session,
4884 const char *shm_path)
4885 {
4886 /* Safety net */
4887 assert(session);
4888
4889 /*
4890 * Can only set shm path before session is started.
4891 */
4892 if (session->has_been_started) {
4893 return LTTNG_ERR_SESSION_STARTED;
4894 }
4895
4896 strncpy(session->shm_path, shm_path,
4897 sizeof(session->shm_path));
4898 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
4899
4900 return 0;
4901 }
4902
4903 /*
4904 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
4905 *
4906 * Ask the consumer to rotate the session output directory.
4907 * The session lock must be held.
4908 *
4909 * Returns LTTNG_OK on success or else a negative LTTng error code.
4910 */
4911 int cmd_rotate_session(struct ltt_session *session,
4912 struct lttng_rotate_session_return *rotate_return,
4913 bool quiet_rotation,
4914 enum lttng_trace_chunk_command_type command)
4915 {
4916 int ret;
4917 uint64_t ongoing_rotation_chunk_id;
4918 enum lttng_error_code cmd_ret = LTTNG_OK;
4919 struct lttng_trace_chunk *chunk_being_archived = NULL;
4920 struct lttng_trace_chunk *new_trace_chunk = NULL;
4921 enum lttng_trace_chunk_status chunk_status;
4922 bool failed_to_rotate = false;
4923 enum lttng_error_code rotation_fail_code = LTTNG_OK;
4924
4925 assert(session);
4926
4927 if (!session->has_been_started) {
4928 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4929 goto end;
4930 }
4931
4932 /*
4933 * Explicit rotation is not supported for live sessions.
4934 * However, live sessions can perform a quiet rotation on
4935 * destroy.
4936 * Rotation is not supported for snapshot traces (no output).
4937 */
4938 if ((!quiet_rotation && session->live_timer) ||
4939 !session->output_traces) {
4940 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
4941 goto end;
4942 }
4943
4944 /* Unsupported feature in lttng-relayd before 2.11. */
4945 if (!quiet_rotation && session->consumer->type == CONSUMER_DST_NET &&
4946 (session->consumer->relay_major_version == 2 &&
4947 session->consumer->relay_minor_version < 11)) {
4948 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
4949 goto end;
4950 }
4951
4952 /* Unsupported feature in lttng-modules before 2.8 (lack of sequence number). */
4953 if (session->kernel_session && !kernel_supports_ring_buffer_packet_sequence_number()) {
4954 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL;
4955 goto end;
4956 }
4957
4958 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
4959 DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
4960 session->name);
4961 cmd_ret = LTTNG_ERR_ROTATION_PENDING;
4962 goto end;
4963 }
4964
4965 /*
4966 * After a stop, we only allow one rotation to occur, the other ones are
4967 * useless until a new start.
4968 */
4969 if (session->rotated_after_last_stop) {
4970 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
4971 session->name);
4972 cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
4973 goto end;
4974 }
4975
4976 /*
4977 * After a stop followed by a clear, disallow following rotations a they would
4978 * generate empty chunks.
4979 */
4980 if (session->cleared_after_last_stop) {
4981 DBG("Session \"%s\" was already cleared after stop, refusing rotation",
4982 session->name);
4983 cmd_ret = LTTNG_ERR_ROTATION_AFTER_STOP_CLEAR;
4984 goto end;
4985 }
4986
4987 if (session->active) {
4988 new_trace_chunk = session_create_new_trace_chunk(session, NULL,
4989 NULL, NULL);
4990 if (!new_trace_chunk) {
4991 cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
4992 goto error;
4993 }
4994 }
4995
4996 /*
4997 * The current trace chunk becomes the chunk being archived.
4998 *
4999 * After this point, "chunk_being_archived" must absolutely
5000 * be closed on the consumer(s), otherwise it will never be
5001 * cleaned-up, which will result in a leak.
5002 */
5003 ret = session_set_trace_chunk(session, new_trace_chunk,
5004 &chunk_being_archived);
5005 if (ret) {
5006 cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
5007 goto error;
5008 }
5009
5010 if (session->kernel_session) {
5011 cmd_ret = kernel_rotate_session(session);
5012 if (cmd_ret != LTTNG_OK) {
5013 failed_to_rotate = true;
5014 rotation_fail_code = cmd_ret;
5015 }
5016 }
5017 if (session->ust_session) {
5018 cmd_ret = ust_app_rotate_session(session);
5019 if (cmd_ret != LTTNG_OK) {
5020 failed_to_rotate = true;
5021 rotation_fail_code = cmd_ret;
5022 }
5023 }
5024
5025 if (!session->active) {
5026 session->rotated_after_last_stop = true;
5027 }
5028
5029 if (!chunk_being_archived) {
5030 DBG("Rotating session \"%s\" from a \"NULL\" trace chunk to a new trace chunk, skipping completion check",
5031 session->name);
5032 if (failed_to_rotate) {
5033 cmd_ret = rotation_fail_code;
5034 goto error;
5035 }
5036 cmd_ret = LTTNG_OK;
5037 goto end;
5038 }
5039
5040 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
5041 chunk_status = lttng_trace_chunk_get_id(chunk_being_archived,
5042 &ongoing_rotation_chunk_id);
5043 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5044
5045 ret = session_close_trace_chunk(session, chunk_being_archived,
5046 command, session->last_chunk_path);
5047 if (ret) {
5048 cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5049 goto error;
5050 }
5051
5052 if (failed_to_rotate) {
5053 cmd_ret = rotation_fail_code;
5054 goto error;
5055 }
5056
5057 session->quiet_rotation = quiet_rotation;
5058 ret = timer_session_rotation_pending_check_start(session,
5059 DEFAULT_ROTATE_PENDING_TIMER);
5060 if (ret) {
5061 cmd_ret = LTTNG_ERR_UNK;
5062 goto error;
5063 }
5064
5065 if (rotate_return) {
5066 rotate_return->rotation_id = ongoing_rotation_chunk_id;
5067 }
5068
5069 session->chunk_being_archived = chunk_being_archived;
5070 chunk_being_archived = NULL;
5071 if (!quiet_rotation) {
5072 ret = notification_thread_command_session_rotation_ongoing(
5073 notification_thread_handle,
5074 session->name, session->uid, session->gid,
5075 ongoing_rotation_chunk_id);
5076 if (ret != LTTNG_OK) {
5077 ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
5078 session->name);
5079 cmd_ret = ret;
5080 }
5081 }
5082
5083 DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
5084 session->name, ongoing_rotation_chunk_id);
5085 end:
5086 lttng_trace_chunk_put(new_trace_chunk);
5087 lttng_trace_chunk_put(chunk_being_archived);
5088 ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
5089 return ret;
5090 error:
5091 if (session_reset_rotation_state(session,
5092 LTTNG_ROTATION_STATE_ERROR)) {
5093 ERR("Failed to reset rotation state of session \"%s\"",
5094 session->name);
5095 }
5096 goto end;
5097 }
5098
5099 /*
5100 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
5101 *
5102 * Check if the session has finished its rotation.
5103 *
5104 * Return LTTNG_OK on success or else an LTTNG_ERR code.
5105 */
5106 int cmd_rotate_get_info(struct ltt_session *session,
5107 struct lttng_rotation_get_info_return *info_return,
5108 uint64_t rotation_id)
5109 {
5110 enum lttng_error_code cmd_ret = LTTNG_OK;
5111 enum lttng_rotation_state rotation_state;
5112
5113 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
5114 session->most_recent_chunk_id.value);
5115
5116 if (session->chunk_being_archived) {
5117 enum lttng_trace_chunk_status chunk_status;
5118 uint64_t chunk_id;
5119
5120 chunk_status = lttng_trace_chunk_get_id(
5121 session->chunk_being_archived,
5122 &chunk_id);
5123 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5124
5125 rotation_state = rotation_id == chunk_id ?
5126 LTTNG_ROTATION_STATE_ONGOING :
5127 LTTNG_ROTATION_STATE_EXPIRED;
5128 } else {
5129 if (session->last_archived_chunk_id.is_set &&
5130 rotation_id != session->last_archived_chunk_id.value) {
5131 rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
5132 } else {
5133 rotation_state = session->rotation_state;
5134 }
5135 }
5136
5137 switch (rotation_state) {
5138 case LTTNG_ROTATION_STATE_NO_ROTATION:
5139 DBG("Reporting that no rotation has occurred within the lifetime of session \"%s\"",
5140 session->name);
5141 goto end;
5142 case LTTNG_ROTATION_STATE_EXPIRED:
5143 DBG("Reporting that the rotation state of rotation id %" PRIu64 " of session \"%s\" has expired",
5144 rotation_id, session->name);
5145 break;
5146 case LTTNG_ROTATION_STATE_ONGOING:
5147 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
5148 rotation_id, session->name);
5149 break;
5150 case LTTNG_ROTATION_STATE_COMPLETED:
5151 {
5152 int fmt_ret;
5153 char *chunk_path;
5154 char *current_tracing_path_reply;
5155 size_t current_tracing_path_reply_len;
5156
5157 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
5158 rotation_id, session->name);
5159
5160 switch (session_get_consumer_destination_type(session)) {
5161 case CONSUMER_DST_LOCAL:
5162 current_tracing_path_reply =
5163 info_return->location.local.absolute_path;
5164 current_tracing_path_reply_len =
5165 sizeof(info_return->location.local.absolute_path);
5166 info_return->location_type =
5167 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
5168 fmt_ret = asprintf(&chunk_path,
5169 "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
5170 session_get_base_path(session),
5171 session->last_archived_chunk_name);
5172 if (fmt_ret == -1) {
5173 PERROR("Failed to format the path of the last archived trace chunk");
5174 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5175 cmd_ret = LTTNG_ERR_UNK;
5176 goto end;
5177 }
5178 break;
5179 case CONSUMER_DST_NET:
5180 {
5181 uint16_t ctrl_port, data_port;
5182
5183 current_tracing_path_reply =
5184 info_return->location.relay.relative_path;
5185 current_tracing_path_reply_len =
5186 sizeof(info_return->location.relay.relative_path);
5187 /* Currently the only supported relay protocol. */
5188 info_return->location.relay.protocol =
5189 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
5190
5191 fmt_ret = lttng_strncpy(info_return->location.relay.host,
5192 session_get_net_consumer_hostname(session),
5193 sizeof(info_return->location.relay.host));
5194 if (fmt_ret) {
5195 ERR("Failed to copy host name to rotate_get_info reply");
5196 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5197 cmd_ret = LTTNG_ERR_SET_URL;
5198 goto end;
5199 }
5200
5201 session_get_net_consumer_ports(session, &ctrl_port, &data_port);
5202 info_return->location.relay.ports.control = ctrl_port;
5203 info_return->location.relay.ports.data = data_port;
5204 info_return->location_type =
5205 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
5206 chunk_path = strdup(session->last_chunk_path);
5207 if (!chunk_path) {
5208 ERR("Failed to allocate the path of the last archived trace chunk");
5209 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5210 cmd_ret = LTTNG_ERR_UNK;
5211 goto end;
5212 }
5213 break;
5214 }
5215 default:
5216 abort();
5217 }
5218
5219 fmt_ret = lttng_strncpy(current_tracing_path_reply,
5220 chunk_path, current_tracing_path_reply_len);
5221 free(chunk_path);
5222 if (fmt_ret) {
5223 ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
5224 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5225 cmd_ret = LTTNG_ERR_UNK;
5226 goto end;
5227 }
5228
5229 break;
5230 }
5231 case LTTNG_ROTATION_STATE_ERROR:
5232 DBG("Reporting that an error occurred during rotation %" PRIu64 " of session \"%s\"",
5233 rotation_id, session->name);
5234 break;
5235 default:
5236 abort();
5237 }
5238
5239 cmd_ret = LTTNG_OK;
5240 end:
5241 info_return->status = (int32_t) rotation_state;
5242 return cmd_ret;
5243 }
5244
5245 /*
5246 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
5247 *
5248 * Configure the automatic rotation parameters.
5249 * 'activate' to true means activate the rotation schedule type with 'new_value'.
5250 * 'activate' to false means deactivate the rotation schedule and validate that
5251 * 'new_value' has the same value as the currently active value.
5252 *
5253 * Return 0 on success or else a positive LTTNG_ERR code.
5254 */
5255 int cmd_rotation_set_schedule(struct ltt_session *session,
5256 bool activate, enum lttng_rotation_schedule_type schedule_type,
5257 uint64_t new_value,
5258 struct notification_thread_handle *notification_thread_handle)
5259 {
5260 int ret;
5261 uint64_t *parameter_value;
5262
5263 assert(session);
5264
5265 DBG("Cmd rotate set schedule session %s", session->name);
5266
5267 if (session->live_timer || !session->output_traces) {
5268 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
5269 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5270 goto end;
5271 }
5272
5273 switch (schedule_type) {
5274 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5275 parameter_value = &session->rotate_size;
5276 break;
5277 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5278 parameter_value = &session->rotate_timer_period;
5279 if (new_value >= UINT_MAX) {
5280 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
5281 new_value, UINT_MAX);
5282 ret = LTTNG_ERR_INVALID;
5283 goto end;
5284 }
5285 break;
5286 default:
5287 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
5288 ret = LTTNG_ERR_INVALID;
5289 goto end;
5290 }
5291
5292 /* Improper use of the API. */
5293 if (new_value == -1ULL) {
5294 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
5295 ret = LTTNG_ERR_INVALID;
5296 goto end;
5297 }
5298
5299 /*
5300 * As indicated in struct ltt_session's comments, a value of == 0 means
5301 * this schedule rotation type is not in use.
5302 *
5303 * Reject the command if we were asked to activate a schedule that was
5304 * already active.
5305 */
5306 if (activate && *parameter_value != 0) {
5307 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
5308 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
5309 goto end;
5310 }
5311
5312 /*
5313 * Reject the command if we were asked to deactivate a schedule that was
5314 * not active.
5315 */
5316 if (!activate && *parameter_value == 0) {
5317 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
5318 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5319 goto end;
5320 }
5321
5322 /*
5323 * Reject the command if we were asked to deactivate a schedule that
5324 * doesn't exist.
5325 */
5326 if (!activate && *parameter_value != new_value) {
5327 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
5328 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5329 goto end;
5330 }
5331
5332 *parameter_value = activate ? new_value : 0;
5333
5334 switch (schedule_type) {
5335 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5336 if (activate && session->active) {
5337 /*
5338 * Only start the timer if the session is active,
5339 * otherwise it will be started when the session starts.
5340 */
5341 ret = timer_session_rotation_schedule_timer_start(
5342 session, new_value);
5343 if (ret) {
5344 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
5345 ret = LTTNG_ERR_UNK;
5346 goto end;
5347 }
5348 } else {
5349 ret = timer_session_rotation_schedule_timer_stop(
5350 session);
5351 if (ret) {
5352 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
5353 ret = LTTNG_ERR_UNK;
5354 goto end;
5355 }
5356 }
5357 break;
5358 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5359 if (activate) {
5360 ret = subscribe_session_consumed_size_rotation(session,
5361 new_value, notification_thread_handle);
5362 if (ret) {
5363 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
5364 ret = LTTNG_ERR_UNK;
5365 goto end;
5366 }
5367 } else {
5368 ret = unsubscribe_session_consumed_size_rotation(session,
5369 notification_thread_handle);
5370 if (ret) {
5371 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
5372 ret = LTTNG_ERR_UNK;
5373 goto end;
5374 }
5375
5376 }
5377 break;
5378 default:
5379 /* Would have been caught before. */
5380 abort();
5381 }
5382
5383 ret = LTTNG_OK;
5384
5385 goto end;
5386
5387 end:
5388 return ret;
5389 }
5390
5391 /* Wait for a given path to be removed before continuing. */
5392 static enum lttng_error_code wait_on_path(void *path_data)
5393 {
5394 const char *shm_path = path_data;
5395
5396 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5397 shm_path);
5398 while (true) {
5399 int ret;
5400 struct stat st;
5401
5402 ret = stat(shm_path, &st);
5403 if (ret) {
5404 if (errno != ENOENT) {
5405 PERROR("stat() returned an error while checking for the existence of the shm path");
5406 } else {
5407 DBG("shm path no longer exists, completing the destruction of session");
5408 }
5409 break;
5410 } else {
5411 if (!S_ISDIR(st.st_mode)) {
5412 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5413 shm_path);
5414 break;
5415 }
5416 }
5417 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
5418 }
5419 return LTTNG_OK;
5420 }
5421
5422 /*
5423 * Returns a pointer to a handler to run on completion of a command.
5424 * Returns NULL if no handler has to be run for the last command executed.
5425 */
5426 const struct cmd_completion_handler *cmd_pop_completion_handler(void)
5427 {
5428 struct cmd_completion_handler *handler = current_completion_handler;
5429
5430 current_completion_handler = NULL;
5431 return handler;
5432 }
5433
5434 /*
5435 * Init command subsystem.
5436 */
5437 void cmd_init(void)
5438 {
5439 /*
5440 * Set network sequence index to 1 for streams to match a relayd
5441 * socket on the consumer side.
5442 */
5443 pthread_mutex_lock(&relayd_net_seq_idx_lock);
5444 relayd_net_seq_idx = 1;
5445 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
5446
5447 DBG("Command subsystem initialized");
5448 }
LTTng tools - Deliverables
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