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SoW-2019-0007-2: Dynamic Snapshot: Triggers send partial event payload with notifications
[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 * SPDX-License-Identifier: GPL-2.0-only
6 *
7 */
8
9 #include "bin/lttng-sessiond/tracker.h"
10 #include "lttng/lttng-error.h"
11 #include "lttng/tracker.h"
12 #define _LGPL_SOURCE
13 #include <assert.h>
14 #include <inttypes.h>
15 #include <urcu/list.h>
16 #include <urcu/uatomic.h>
17 #include <sys/stat.h>
18 #include <stdio.h>
19
20 #include <common/defaults.h>
21 #include <common/common.h>
22 #include <common/sessiond-comm/sessiond-comm.h>
23 #include <common/relayd/relayd.h>
24 #include <common/utils.h>
25 #include <common/compat/string.h>
26 #include <common/kernel-ctl/kernel-ctl.h>
27 #include <common/dynamic-buffer.h>
28 #include <common/buffer-view.h>
29 #include <common/trace-chunk.h>
30 #include <lttng/location-internal.h>
31 #include <lttng/trigger/trigger-internal.h>
32 #include <lttng/condition/condition.h>
33 #include <lttng/condition/condition-internal.h>
34 #include <lttng/condition/event-rule.h>
35 #include <lttng/condition/event-rule-internal.h>
36 #include <lttng/event-rule/event-rule.h>
37 #include <lttng/event-rule/event-rule-internal.h>
38 #include <lttng/event-rule/uprobe-internal.h>
39 #include <lttng/event-rule/tracepoint.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_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_ENABLE_CHANNEL processed by the client thread.
1446 *
1447 * The wpipe arguments is used as a notifier for the kernel thread.
1448 */
1449 int cmd_enable_channel(struct ltt_session *session,
1450 const struct lttng_domain *domain, const struct lttng_channel *_attr, int wpipe)
1451 {
1452 int ret;
1453 struct ltt_ust_session *usess = session->ust_session;
1454 struct lttng_ht *chan_ht;
1455 size_t len;
1456 struct lttng_channel attr;
1457
1458 assert(session);
1459 assert(_attr);
1460 assert(domain);
1461
1462 attr = *_attr;
1463 len = lttng_strnlen(attr.name, sizeof(attr.name));
1464
1465 /* Validate channel name */
1466 if (attr.name[0] == '.' ||
1467 memchr(attr.name, '/', len) != NULL) {
1468 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1469 goto end;
1470 }
1471
1472 DBG("Enabling channel %s for session %s", attr.name, session->name);
1473
1474 rcu_read_lock();
1475
1476 /*
1477 * Don't try to enable a channel if the session has been started at
1478 * some point in time before. The tracer does not allow it.
1479 */
1480 if (session->has_been_started) {
1481 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1482 goto error;
1483 }
1484
1485 /*
1486 * If the session is a live session, remove the switch timer, the
1487 * live timer does the same thing but sends also synchronisation
1488 * beacons for inactive streams.
1489 */
1490 if (session->live_timer > 0) {
1491 attr.attr.live_timer_interval = session->live_timer;
1492 attr.attr.switch_timer_interval = 0;
1493 }
1494
1495 /* Check for feature support */
1496 switch (domain->type) {
1497 case LTTNG_DOMAIN_KERNEL:
1498 {
1499 if (kernel_supports_ring_buffer_snapshot_sample_positions() != 1) {
1500 /* Sampling position of buffer is not supported */
1501 WARN("Kernel tracer does not support buffer monitoring. "
1502 "Setting the monitor interval timer to 0 "
1503 "(disabled) for channel '%s' of session '%s'",
1504 attr.name, session->name);
1505 lttng_channel_set_monitor_timer_interval(&attr, 0);
1506 }
1507 break;
1508 }
1509 case LTTNG_DOMAIN_UST:
1510 break;
1511 case LTTNG_DOMAIN_JUL:
1512 case LTTNG_DOMAIN_LOG4J:
1513 case LTTNG_DOMAIN_PYTHON:
1514 if (!agent_tracing_is_enabled()) {
1515 DBG("Attempted to enable a channel in an agent domain but the agent thread is not running");
1516 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
1517 goto error;
1518 }
1519 break;
1520 default:
1521 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1522 goto error;
1523 }
1524
1525 switch (domain->type) {
1526 case LTTNG_DOMAIN_KERNEL:
1527 {
1528 struct ltt_kernel_channel *kchan;
1529
1530 kchan = trace_kernel_get_channel_by_name(attr.name,
1531 session->kernel_session);
1532 if (kchan == NULL) {
1533 if (session->snapshot.nb_output > 0 ||
1534 session->snapshot_mode) {
1535 /* Enforce mmap output for snapshot sessions. */
1536 attr.attr.output = LTTNG_EVENT_MMAP;
1537 }
1538 ret = channel_kernel_create(session->kernel_session, &attr, wpipe);
1539 if (attr.name[0] != '\0') {
1540 session->kernel_session->has_non_default_channel = 1;
1541 }
1542 } else {
1543 ret = channel_kernel_enable(session->kernel_session, kchan);
1544 }
1545
1546 if (ret != LTTNG_OK) {
1547 goto error;
1548 }
1549
1550 kernel_wait_quiescent();
1551 break;
1552 }
1553 case LTTNG_DOMAIN_UST:
1554 case LTTNG_DOMAIN_JUL:
1555 case LTTNG_DOMAIN_LOG4J:
1556 case LTTNG_DOMAIN_PYTHON:
1557 {
1558 struct ltt_ust_channel *uchan;
1559
1560 /*
1561 * FIXME
1562 *
1563 * Current agent implementation limitations force us to allow
1564 * only one channel at once in "agent" subdomains. Each
1565 * subdomain has a default channel name which must be strictly
1566 * adhered to.
1567 */
1568 if (domain->type == LTTNG_DOMAIN_JUL) {
1569 if (strncmp(attr.name, DEFAULT_JUL_CHANNEL_NAME,
1570 LTTNG_SYMBOL_NAME_LEN)) {
1571 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1572 goto error;
1573 }
1574 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1575 if (strncmp(attr.name, DEFAULT_LOG4J_CHANNEL_NAME,
1576 LTTNG_SYMBOL_NAME_LEN)) {
1577 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1578 goto error;
1579 }
1580 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1581 if (strncmp(attr.name, DEFAULT_PYTHON_CHANNEL_NAME,
1582 LTTNG_SYMBOL_NAME_LEN)) {
1583 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1584 goto error;
1585 }
1586 }
1587
1588 chan_ht = usess->domain_global.channels;
1589
1590 uchan = trace_ust_find_channel_by_name(chan_ht, attr.name);
1591 if (uchan == NULL) {
1592 ret = channel_ust_create(usess, &attr, domain->buf_type);
1593 if (attr.name[0] != '\0') {
1594 usess->has_non_default_channel = 1;
1595 }
1596 } else {
1597 ret = channel_ust_enable(usess, uchan);
1598 }
1599 break;
1600 }
1601 default:
1602 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1603 goto error;
1604 }
1605
1606 if (ret == LTTNG_OK && attr.attr.output != LTTNG_EVENT_MMAP) {
1607 session->has_non_mmap_channel = true;
1608 }
1609 error:
1610 rcu_read_unlock();
1611 end:
1612 return ret;
1613 }
1614
1615 enum lttng_error_code cmd_process_attr_tracker_get_tracking_policy(
1616 struct ltt_session *session,
1617 enum lttng_domain_type domain,
1618 enum lttng_process_attr process_attr,
1619 enum lttng_tracking_policy *policy)
1620 {
1621 enum lttng_error_code ret_code = LTTNG_OK;
1622 const struct process_attr_tracker *tracker;
1623
1624 switch (domain) {
1625 case LTTNG_DOMAIN_KERNEL:
1626 if (!session->kernel_session) {
1627 ret_code = LTTNG_ERR_INVALID;
1628 goto end;
1629 }
1630 tracker = kernel_get_process_attr_tracker(
1631 session->kernel_session, process_attr);
1632 break;
1633 case LTTNG_DOMAIN_UST:
1634 if (!session->ust_session) {
1635 ret_code = LTTNG_ERR_INVALID;
1636 goto end;
1637 }
1638 tracker = trace_ust_get_process_attr_tracker(
1639 session->ust_session, process_attr);
1640 break;
1641 default:
1642 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1643 goto end;
1644 }
1645 if (tracker) {
1646 *policy = process_attr_tracker_get_tracking_policy(tracker);
1647 } else {
1648 ret_code = LTTNG_ERR_INVALID;
1649 }
1650 end:
1651 return ret_code;
1652 }
1653
1654 enum lttng_error_code cmd_process_attr_tracker_set_tracking_policy(
1655 struct ltt_session *session,
1656 enum lttng_domain_type domain,
1657 enum lttng_process_attr process_attr,
1658 enum lttng_tracking_policy policy)
1659 {
1660 enum lttng_error_code ret_code = LTTNG_OK;
1661
1662 switch (policy) {
1663 case LTTNG_TRACKING_POLICY_INCLUDE_SET:
1664 case LTTNG_TRACKING_POLICY_EXCLUDE_ALL:
1665 case LTTNG_TRACKING_POLICY_INCLUDE_ALL:
1666 break;
1667 default:
1668 ret_code = LTTNG_ERR_INVALID;
1669 goto end;
1670 }
1671
1672 switch (domain) {
1673 case LTTNG_DOMAIN_KERNEL:
1674 if (!session->kernel_session) {
1675 ret_code = LTTNG_ERR_INVALID;
1676 goto end;
1677 }
1678 ret_code = kernel_process_attr_tracker_set_tracking_policy(
1679 session->kernel_session, process_attr, policy);
1680 break;
1681 case LTTNG_DOMAIN_UST:
1682 if (!session->ust_session) {
1683 ret_code = LTTNG_ERR_INVALID;
1684 goto end;
1685 }
1686 ret_code = trace_ust_process_attr_tracker_set_tracking_policy(
1687 session->ust_session, process_attr, policy);
1688 break;
1689 default:
1690 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1691 break;
1692 }
1693 end:
1694 return ret_code;
1695 }
1696
1697 enum lttng_error_code cmd_process_attr_tracker_inclusion_set_add_value(
1698 struct ltt_session *session,
1699 enum lttng_domain_type domain,
1700 enum lttng_process_attr process_attr,
1701 const struct process_attr_value *value)
1702 {
1703 enum lttng_error_code ret_code = LTTNG_OK;
1704
1705 switch (domain) {
1706 case LTTNG_DOMAIN_KERNEL:
1707 if (!session->kernel_session) {
1708 ret_code = LTTNG_ERR_INVALID;
1709 goto end;
1710 }
1711 ret_code = kernel_process_attr_tracker_inclusion_set_add_value(
1712 session->kernel_session, process_attr, value);
1713 break;
1714 case LTTNG_DOMAIN_UST:
1715 if (!session->ust_session) {
1716 ret_code = LTTNG_ERR_INVALID;
1717 goto end;
1718 }
1719 ret_code = trace_ust_process_attr_tracker_inclusion_set_add_value(
1720 session->ust_session, process_attr, value);
1721 break;
1722 default:
1723 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1724 break;
1725 }
1726 end:
1727 return ret_code;
1728 }
1729
1730 enum lttng_error_code cmd_process_attr_tracker_inclusion_set_remove_value(
1731 struct ltt_session *session,
1732 enum lttng_domain_type domain,
1733 enum lttng_process_attr process_attr,
1734 const struct process_attr_value *value)
1735 {
1736 enum lttng_error_code ret_code = LTTNG_OK;
1737
1738 switch (domain) {
1739 case LTTNG_DOMAIN_KERNEL:
1740 if (!session->kernel_session) {
1741 ret_code = LTTNG_ERR_INVALID;
1742 goto end;
1743 }
1744 ret_code = kernel_process_attr_tracker_inclusion_set_remove_value(
1745 session->kernel_session, process_attr, value);
1746 break;
1747 case LTTNG_DOMAIN_UST:
1748 if (!session->ust_session) {
1749 ret_code = LTTNG_ERR_INVALID;
1750 goto end;
1751 }
1752 ret_code = trace_ust_process_attr_tracker_inclusion_set_remove_value(
1753 session->ust_session, process_attr, value);
1754 break;
1755 default:
1756 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1757 break;
1758 }
1759 end:
1760 return ret_code;
1761 }
1762
1763 enum lttng_error_code cmd_process_attr_tracker_get_inclusion_set(
1764 struct ltt_session *session,
1765 enum lttng_domain_type domain,
1766 enum lttng_process_attr process_attr,
1767 struct lttng_process_attr_values **values)
1768 {
1769 enum lttng_error_code ret_code = LTTNG_OK;
1770 const struct process_attr_tracker *tracker;
1771 enum process_attr_tracker_status status;
1772
1773 switch (domain) {
1774 case LTTNG_DOMAIN_KERNEL:
1775 if (!session->kernel_session) {
1776 ret_code = LTTNG_ERR_INVALID;
1777 goto end;
1778 }
1779 tracker = kernel_get_process_attr_tracker(
1780 session->kernel_session, process_attr);
1781 break;
1782 case LTTNG_DOMAIN_UST:
1783 if (!session->ust_session) {
1784 ret_code = LTTNG_ERR_INVALID;
1785 goto end;
1786 }
1787 tracker = trace_ust_get_process_attr_tracker(
1788 session->ust_session, process_attr);
1789 break;
1790 default:
1791 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1792 goto end;
1793 }
1794
1795 if (!tracker) {
1796 ret_code = LTTNG_ERR_INVALID;
1797 goto end;
1798 }
1799
1800 status = process_attr_tracker_get_inclusion_set(tracker, values);
1801 switch (status) {
1802 case PROCESS_ATTR_TRACKER_STATUS_OK:
1803 ret_code = LTTNG_OK;
1804 break;
1805 case PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY:
1806 ret_code = LTTNG_ERR_PROCESS_ATTR_TRACKER_INVALID_TRACKING_POLICY;
1807 break;
1808 case PROCESS_ATTR_TRACKER_STATUS_ERROR:
1809 ret_code = LTTNG_ERR_NOMEM;
1810 break;
1811 default:
1812 ret_code = LTTNG_ERR_UNK;
1813 break;
1814 }
1815
1816 end:
1817 return ret_code;
1818 }
1819
1820 /*
1821 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1822 */
1823 int cmd_disable_event(struct ltt_session *session,
1824 enum lttng_domain_type domain, const char *channel_name,
1825 const struct lttng_event *event)
1826 {
1827 int ret;
1828 const char *event_name;
1829
1830 DBG("Disable event command for event \'%s\'", event->name);
1831
1832 event_name = event->name;
1833
1834 /* Error out on unhandled search criteria */
1835 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1836 || event->pid || event->filter || event->exclusion) {
1837 ret = LTTNG_ERR_UNK;
1838 goto error;
1839 }
1840
1841 rcu_read_lock();
1842
1843 switch (domain) {
1844 case LTTNG_DOMAIN_KERNEL:
1845 {
1846 struct ltt_kernel_channel *kchan;
1847 struct ltt_kernel_session *ksess;
1848
1849 ksess = session->kernel_session;
1850
1851 /*
1852 * If a non-default channel has been created in the
1853 * session, explicitely require that -c chan_name needs
1854 * to be provided.
1855 */
1856 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1857 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1858 goto error_unlock;
1859 }
1860
1861 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1862 if (kchan == NULL) {
1863 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1864 goto error_unlock;
1865 }
1866
1867 switch (event->type) {
1868 case LTTNG_EVENT_ALL:
1869 case LTTNG_EVENT_TRACEPOINT:
1870 case LTTNG_EVENT_SYSCALL:
1871 case LTTNG_EVENT_PROBE:
1872 case LTTNG_EVENT_FUNCTION:
1873 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1874 if (event_name[0] == '\0') {
1875 ret = event_kernel_disable_event(kchan,
1876 NULL, event->type);
1877 } else {
1878 ret = event_kernel_disable_event(kchan,
1879 event_name, event->type);
1880 }
1881 if (ret != LTTNG_OK) {
1882 goto error_unlock;
1883 }
1884 break;
1885 default:
1886 ret = LTTNG_ERR_UNK;
1887 goto error_unlock;
1888 }
1889
1890 kernel_wait_quiescent();
1891 break;
1892 }
1893 case LTTNG_DOMAIN_UST:
1894 {
1895 struct ltt_ust_channel *uchan;
1896 struct ltt_ust_session *usess;
1897
1898 usess = session->ust_session;
1899
1900 if (validate_ust_event_name(event_name)) {
1901 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1902 goto error_unlock;
1903 }
1904
1905 /*
1906 * If a non-default channel has been created in the
1907 * session, explicitly require that -c chan_name needs
1908 * to be provided.
1909 */
1910 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1911 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1912 goto error_unlock;
1913 }
1914
1915 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1916 channel_name);
1917 if (uchan == NULL) {
1918 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1919 goto error_unlock;
1920 }
1921
1922 switch (event->type) {
1923 case LTTNG_EVENT_ALL:
1924 /*
1925 * An empty event name means that everything
1926 * should be disabled.
1927 */
1928 if (event->name[0] == '\0') {
1929 ret = event_ust_disable_all_tracepoints(usess, uchan);
1930 } else {
1931 ret = event_ust_disable_tracepoint(usess, uchan,
1932 event_name);
1933 }
1934 if (ret != LTTNG_OK) {
1935 goto error_unlock;
1936 }
1937 break;
1938 default:
1939 ret = LTTNG_ERR_UNK;
1940 goto error_unlock;
1941 }
1942
1943 DBG3("Disable UST event %s in channel %s completed", event_name,
1944 channel_name);
1945 break;
1946 }
1947 case LTTNG_DOMAIN_LOG4J:
1948 case LTTNG_DOMAIN_JUL:
1949 case LTTNG_DOMAIN_PYTHON:
1950 {
1951 struct agent *agt;
1952 struct ltt_ust_session *usess = session->ust_session;
1953
1954 assert(usess);
1955
1956 switch (event->type) {
1957 case LTTNG_EVENT_ALL:
1958 break;
1959 default:
1960 ret = LTTNG_ERR_UNK;
1961 goto error_unlock;
1962 }
1963
1964 agt = trace_ust_find_agent(usess, domain);
1965 if (!agt) {
1966 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1967 goto error_unlock;
1968 }
1969 /*
1970 * An empty event name means that everything
1971 * should be disabled.
1972 */
1973 if (event->name[0] == '\0') {
1974 ret = event_agent_disable_all(usess, agt);
1975 } else {
1976 ret = event_agent_disable(usess, agt, event_name);
1977 }
1978 if (ret != LTTNG_OK) {
1979 goto error_unlock;
1980 }
1981
1982 break;
1983 }
1984 default:
1985 ret = LTTNG_ERR_UND;
1986 goto error_unlock;
1987 }
1988
1989 ret = LTTNG_OK;
1990
1991 error_unlock:
1992 rcu_read_unlock();
1993 error:
1994 return ret;
1995 }
1996
1997 /*
1998 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1999 */
2000 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
2001 char *channel_name, const struct lttng_event_context *ctx, int kwpipe)
2002 {
2003 int ret, chan_kern_created = 0, chan_ust_created = 0;
2004 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
2005
2006 /*
2007 * Don't try to add a context if the session has been started at
2008 * some point in time before. The tracer does not allow it and would
2009 * result in a corrupted trace.
2010 */
2011 if (session->has_been_started) {
2012 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2013 goto end;
2014 }
2015
2016 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
2017 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
2018 app_ctx_name = ctx->u.app_ctx.ctx_name;
2019 }
2020
2021 switch (domain) {
2022 case LTTNG_DOMAIN_KERNEL:
2023 assert(session->kernel_session);
2024
2025 if (session->kernel_session->channel_count == 0) {
2026 /* Create default channel */
2027 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
2028 if (ret != LTTNG_OK) {
2029 goto error;
2030 }
2031 chan_kern_created = 1;
2032 }
2033 /* Add kernel context to kernel tracer */
2034 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
2035 if (ret != LTTNG_OK) {
2036 goto error;
2037 }
2038 break;
2039 case LTTNG_DOMAIN_JUL:
2040 case LTTNG_DOMAIN_LOG4J:
2041 {
2042 /*
2043 * Validate channel name.
2044 * If no channel name is given and the domain is JUL or LOG4J,
2045 * set it to the appropriate domain-specific channel name. If
2046 * a name is provided but does not match the expexted channel
2047 * name, return an error.
2048 */
2049 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
2050 strcmp(channel_name,
2051 DEFAULT_JUL_CHANNEL_NAME)) {
2052 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2053 goto error;
2054 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
2055 strcmp(channel_name,
2056 DEFAULT_LOG4J_CHANNEL_NAME)) {
2057 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2058 goto error;
2059 }
2060 /* break is _not_ missing here. */
2061 }
2062 case LTTNG_DOMAIN_UST:
2063 {
2064 struct ltt_ust_session *usess = session->ust_session;
2065 unsigned int chan_count;
2066
2067 assert(usess);
2068
2069 chan_count = lttng_ht_get_count(usess->domain_global.channels);
2070 if (chan_count == 0) {
2071 struct lttng_channel *attr;
2072 /* Create default channel */
2073 attr = channel_new_default_attr(domain, usess->buffer_type);
2074 if (attr == NULL) {
2075 ret = LTTNG_ERR_FATAL;
2076 goto error;
2077 }
2078
2079 ret = channel_ust_create(usess, attr, usess->buffer_type);
2080 if (ret != LTTNG_OK) {
2081 free(attr);
2082 goto error;
2083 }
2084 channel_attr_destroy(attr);
2085 chan_ust_created = 1;
2086 }
2087
2088 ret = context_ust_add(usess, domain, ctx, channel_name);
2089 free(app_ctx_provider_name);
2090 free(app_ctx_name);
2091 app_ctx_name = NULL;
2092 app_ctx_provider_name = NULL;
2093 if (ret != LTTNG_OK) {
2094 goto error;
2095 }
2096 break;
2097 }
2098 default:
2099 ret = LTTNG_ERR_UND;
2100 goto error;
2101 }
2102
2103 ret = LTTNG_OK;
2104 goto end;
2105
2106 error:
2107 if (chan_kern_created) {
2108 struct ltt_kernel_channel *kchan =
2109 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
2110 session->kernel_session);
2111 /* Created previously, this should NOT fail. */
2112 assert(kchan);
2113 kernel_destroy_channel(kchan);
2114 }
2115
2116 if (chan_ust_created) {
2117 struct ltt_ust_channel *uchan =
2118 trace_ust_find_channel_by_name(
2119 session->ust_session->domain_global.channels,
2120 DEFAULT_CHANNEL_NAME);
2121 /* Created previously, this should NOT fail. */
2122 assert(uchan);
2123 /* Remove from the channel list of the session. */
2124 trace_ust_delete_channel(session->ust_session->domain_global.channels,
2125 uchan);
2126 trace_ust_destroy_channel(uchan);
2127 }
2128 end:
2129 free(app_ctx_provider_name);
2130 free(app_ctx_name);
2131 return ret;
2132 }
2133
2134 static inline bool name_starts_with(const char *name, const char *prefix)
2135 {
2136 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
2137
2138 return !strncmp(name, prefix, max_cmp_len);
2139 }
2140
2141 /* Perform userspace-specific event name validation */
2142 static int validate_ust_event_name(const char *name)
2143 {
2144 int ret = 0;
2145
2146 if (!name) {
2147 ret = -1;
2148 goto end;
2149 }
2150
2151 /*
2152 * Check name against all internal UST event component namespaces used
2153 * by the agents.
2154 */
2155 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
2156 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
2157 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
2158 ret = -1;
2159 }
2160
2161 end:
2162 return ret;
2163 }
2164
2165 /*
2166 * Internal version of cmd_enable_event() with a supplemental
2167 * "internal_event" flag which is used to enable internal events which should
2168 * be hidden from clients. Such events are used in the agent implementation to
2169 * enable the events through which all "agent" events are funeled.
2170 */
2171 static int _cmd_enable_event(struct ltt_session *session,
2172 const struct lttng_domain *domain,
2173 char *channel_name, struct lttng_event *event,
2174 char *filter_expression,
2175 struct lttng_bytecode *filter,
2176 struct lttng_event_exclusion *exclusion,
2177 int wpipe, bool internal_event)
2178 {
2179 int ret = 0, channel_created = 0;
2180 struct lttng_channel *attr = NULL;
2181
2182 assert(session);
2183 assert(event);
2184 assert(channel_name);
2185
2186 /* If we have a filter, we must have its filter expression */
2187 assert(!(!!filter_expression ^ !!filter));
2188
2189 /* Normalize event name as a globbing pattern */
2190 strutils_normalize_star_glob_pattern(event->name);
2191
2192 /* Normalize exclusion names as globbing patterns */
2193 if (exclusion) {
2194 size_t i;
2195
2196 for (i = 0; i < exclusion->count; i++) {
2197 char *name = LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
2198
2199 strutils_normalize_star_glob_pattern(name);
2200 }
2201 }
2202
2203 DBG("Enable event command for event \'%s\'", event->name);
2204
2205 rcu_read_lock();
2206
2207 switch (domain->type) {
2208 case LTTNG_DOMAIN_KERNEL:
2209 {
2210 struct ltt_kernel_channel *kchan;
2211
2212 /*
2213 * If a non-default channel has been created in the
2214 * session, explicitely require that -c chan_name needs
2215 * to be provided.
2216 */
2217 if (session->kernel_session->has_non_default_channel
2218 && channel_name[0] == '\0') {
2219 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2220 goto error;
2221 }
2222
2223 kchan = trace_kernel_get_channel_by_name(channel_name,
2224 session->kernel_session);
2225 if (kchan == NULL) {
2226 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
2227 LTTNG_BUFFER_GLOBAL);
2228 if (attr == NULL) {
2229 ret = LTTNG_ERR_FATAL;
2230 goto error;
2231 }
2232 if (lttng_strncpy(attr->name, channel_name,
2233 sizeof(attr->name))) {
2234 ret = LTTNG_ERR_INVALID;
2235 goto error;
2236 }
2237
2238 ret = cmd_enable_channel(session, domain, attr, wpipe);
2239 if (ret != LTTNG_OK) {
2240 goto error;
2241 }
2242 channel_created = 1;
2243 }
2244
2245 /* Get the newly created kernel channel pointer */
2246 kchan = trace_kernel_get_channel_by_name(channel_name,
2247 session->kernel_session);
2248 if (kchan == NULL) {
2249 /* This sould not happen... */
2250 ret = LTTNG_ERR_FATAL;
2251 goto error;
2252 }
2253
2254 switch (event->type) {
2255 case LTTNG_EVENT_ALL:
2256 {
2257 char *filter_expression_a = NULL;
2258 struct lttng_bytecode *filter_a = NULL;
2259
2260 /*
2261 * We need to duplicate filter_expression and filter,
2262 * because ownership is passed to first enable
2263 * event.
2264 */
2265 if (filter_expression) {
2266 filter_expression_a = strdup(filter_expression);
2267 if (!filter_expression_a) {
2268 ret = LTTNG_ERR_FATAL;
2269 goto error;
2270 }
2271 }
2272 if (filter) {
2273 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
2274 if (!filter_a) {
2275 free(filter_expression_a);
2276 ret = LTTNG_ERR_FATAL;
2277 goto error;
2278 }
2279 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
2280 }
2281 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
2282 ret = event_kernel_enable_event(kchan, event,
2283 filter_expression, filter);
2284 /* We have passed ownership */
2285 filter_expression = NULL;
2286 filter = NULL;
2287 if (ret != LTTNG_OK) {
2288 if (channel_created) {
2289 /* Let's not leak a useless channel. */
2290 kernel_destroy_channel(kchan);
2291 }
2292 free(filter_expression_a);
2293 free(filter_a);
2294 goto error;
2295 }
2296 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
2297 ret = event_kernel_enable_event(kchan, event,
2298 filter_expression_a, filter_a);
2299 /* We have passed ownership */
2300 filter_expression_a = NULL;
2301 filter_a = NULL;
2302 if (ret != LTTNG_OK) {
2303 goto error;
2304 }
2305 break;
2306 }
2307 case LTTNG_EVENT_PROBE:
2308 case LTTNG_EVENT_USERSPACE_PROBE:
2309 case LTTNG_EVENT_FUNCTION:
2310 case LTTNG_EVENT_FUNCTION_ENTRY:
2311 case LTTNG_EVENT_TRACEPOINT:
2312 ret = event_kernel_enable_event(kchan, event,
2313 filter_expression, filter);
2314 /* We have passed ownership */
2315 filter_expression = NULL;
2316 filter = NULL;
2317 if (ret != LTTNG_OK) {
2318 if (channel_created) {
2319 /* Let's not leak a useless channel. */
2320 kernel_destroy_channel(kchan);
2321 }
2322 goto error;
2323 }
2324 break;
2325 case LTTNG_EVENT_SYSCALL:
2326 ret = event_kernel_enable_event(kchan, event,
2327 filter_expression, filter);
2328 /* We have passed ownership */
2329 filter_expression = NULL;
2330 filter = NULL;
2331 if (ret != LTTNG_OK) {
2332 goto error;
2333 }
2334 break;
2335 default:
2336 ret = LTTNG_ERR_UNK;
2337 goto error;
2338 }
2339
2340 kernel_wait_quiescent();
2341 break;
2342 }
2343 case LTTNG_DOMAIN_UST:
2344 {
2345 struct ltt_ust_channel *uchan;
2346 struct ltt_ust_session *usess = session->ust_session;
2347
2348 assert(usess);
2349
2350 /*
2351 * If a non-default channel has been created in the
2352 * session, explicitely require that -c chan_name needs
2353 * to be provided.
2354 */
2355 if (usess->has_non_default_channel && channel_name[0] == '\0') {
2356 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2357 goto error;
2358 }
2359
2360 /* Get channel from global UST domain */
2361 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2362 channel_name);
2363 if (uchan == NULL) {
2364 /* Create default channel */
2365 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
2366 usess->buffer_type);
2367 if (attr == NULL) {
2368 ret = LTTNG_ERR_FATAL;
2369 goto error;
2370 }
2371 if (lttng_strncpy(attr->name, channel_name,
2372 sizeof(attr->name))) {
2373 ret = LTTNG_ERR_INVALID;
2374 goto error;
2375 }
2376
2377 ret = cmd_enable_channel(session, domain, attr, wpipe);
2378 if (ret != LTTNG_OK) {
2379 goto error;
2380 }
2381
2382 /* Get the newly created channel reference back */
2383 uchan = trace_ust_find_channel_by_name(
2384 usess->domain_global.channels, channel_name);
2385 assert(uchan);
2386 }
2387
2388 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2389 /*
2390 * Don't allow users to add UST events to channels which
2391 * are assigned to a userspace subdomain (JUL, Log4J,
2392 * Python, etc.).
2393 */
2394 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2395 goto error;
2396 }
2397
2398 if (!internal_event) {
2399 /*
2400 * Ensure the event name is not reserved for internal
2401 * use.
2402 */
2403 ret = validate_ust_event_name(event->name);
2404 if (ret) {
2405 WARN("Userspace event name %s failed validation.",
2406 event->name);
2407 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2408 goto error;
2409 }
2410 }
2411
2412 /* At this point, the session and channel exist on the tracer */
2413 ret = event_ust_enable_tracepoint(usess, uchan, event,
2414 filter_expression, filter, exclusion,
2415 internal_event);
2416 /* We have passed ownership */
2417 filter_expression = NULL;
2418 filter = NULL;
2419 exclusion = NULL;
2420 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2421 goto already_enabled;
2422 } else if (ret != LTTNG_OK) {
2423 goto error;
2424 }
2425 break;
2426 }
2427 case LTTNG_DOMAIN_LOG4J:
2428 case LTTNG_DOMAIN_JUL:
2429 case LTTNG_DOMAIN_PYTHON:
2430 {
2431 const char *default_event_name, *default_chan_name;
2432 struct agent *agt;
2433 struct lttng_event uevent;
2434 struct lttng_domain tmp_dom;
2435 struct ltt_ust_session *usess = session->ust_session;
2436
2437 assert(usess);
2438
2439 if (!agent_tracing_is_enabled()) {
2440 DBG("Attempted to enable an event in an agent domain but the agent thread is not running");
2441 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
2442 goto error;
2443 }
2444
2445 agt = trace_ust_find_agent(usess, domain->type);
2446 if (!agt) {
2447 agt = agent_create(domain->type);
2448 if (!agt) {
2449 ret = LTTNG_ERR_NOMEM;
2450 goto error;
2451 }
2452 agent_add(agt, usess->agents);
2453 }
2454
2455 /* Create the default tracepoint. */
2456 memset(&uevent, 0, sizeof(uevent));
2457 uevent.type = LTTNG_EVENT_TRACEPOINT;
2458 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2459 default_event_name = event_get_default_agent_ust_name(
2460 domain->type);
2461 if (!default_event_name) {
2462 ret = LTTNG_ERR_FATAL;
2463 goto error;
2464 }
2465 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2466 uevent.name[sizeof(uevent.name) - 1] = '\0';
2467
2468 /*
2469 * The domain type is changed because we are about to enable the
2470 * default channel and event for the JUL domain that are hardcoded.
2471 * This happens in the UST domain.
2472 */
2473 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2474 tmp_dom.type = LTTNG_DOMAIN_UST;
2475
2476 switch (domain->type) {
2477 case LTTNG_DOMAIN_LOG4J:
2478 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2479 break;
2480 case LTTNG_DOMAIN_JUL:
2481 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2482 break;
2483 case LTTNG_DOMAIN_PYTHON:
2484 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2485 break;
2486 default:
2487 /* The switch/case we are in makes this impossible */
2488 assert(0);
2489 }
2490
2491 {
2492 char *filter_expression_copy = NULL;
2493 struct lttng_bytecode *filter_copy = NULL;
2494
2495 if (filter) {
2496 const size_t filter_size = sizeof(
2497 struct lttng_bytecode)
2498 + filter->len;
2499
2500 filter_copy = zmalloc(filter_size);
2501 if (!filter_copy) {
2502 ret = LTTNG_ERR_NOMEM;
2503 goto error;
2504 }
2505 memcpy(filter_copy, filter, filter_size);
2506
2507 filter_expression_copy =
2508 strdup(filter_expression);
2509 if (!filter_expression) {
2510 ret = LTTNG_ERR_NOMEM;
2511 }
2512
2513 if (!filter_expression_copy || !filter_copy) {
2514 free(filter_expression_copy);
2515 free(filter_copy);
2516 goto error;
2517 }
2518 }
2519
2520 ret = cmd_enable_event_internal(session, &tmp_dom,
2521 (char *) default_chan_name,
2522 &uevent, filter_expression_copy,
2523 filter_copy, NULL, wpipe);
2524 }
2525
2526 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2527 goto already_enabled;
2528 } else if (ret != LTTNG_OK) {
2529 goto error;
2530 }
2531
2532 /* The wild card * means that everything should be enabled. */
2533 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2534 ret = event_agent_enable_all(usess, agt, event, filter,
2535 filter_expression);
2536 } else {
2537 ret = event_agent_enable(usess, agt, event, filter,
2538 filter_expression);
2539 }
2540 filter = NULL;
2541 filter_expression = NULL;
2542 if (ret != LTTNG_OK) {
2543 goto error;
2544 }
2545
2546 break;
2547 }
2548 default:
2549 ret = LTTNG_ERR_UND;
2550 goto error;
2551 }
2552
2553 ret = LTTNG_OK;
2554
2555 already_enabled:
2556 error:
2557 free(filter_expression);
2558 free(filter);
2559 free(exclusion);
2560 channel_attr_destroy(attr);
2561 rcu_read_unlock();
2562 return ret;
2563 }
2564
2565 /*
2566 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2567 * We own filter, exclusion, and filter_expression.
2568 */
2569 int cmd_enable_event(struct ltt_session *session,
2570 const struct lttng_domain *domain,
2571 char *channel_name, struct lttng_event *event,
2572 char *filter_expression,
2573 struct lttng_bytecode *filter,
2574 struct lttng_event_exclusion *exclusion,
2575 int wpipe)
2576 {
2577 return _cmd_enable_event(session, domain, channel_name, event,
2578 filter_expression, filter, exclusion, wpipe, false);
2579 }
2580
2581 /*
2582 * Enable an event which is internal to LTTng. An internal should
2583 * never be made visible to clients and are immune to checks such as
2584 * reserved names.
2585 */
2586 static int cmd_enable_event_internal(struct ltt_session *session,
2587 const struct lttng_domain *domain,
2588 char *channel_name, struct lttng_event *event,
2589 char *filter_expression,
2590 struct lttng_bytecode *filter,
2591 struct lttng_event_exclusion *exclusion,
2592 int wpipe)
2593 {
2594 return _cmd_enable_event(session, domain, channel_name, event,
2595 filter_expression, filter, exclusion, wpipe, true);
2596 }
2597
2598 /*
2599 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2600 */
2601 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2602 struct lttng_event **events)
2603 {
2604 int ret;
2605 ssize_t nb_events = 0;
2606
2607 switch (domain) {
2608 case LTTNG_DOMAIN_KERNEL:
2609 nb_events = kernel_list_events(events);
2610 if (nb_events < 0) {
2611 ret = LTTNG_ERR_KERN_LIST_FAIL;
2612 goto error;
2613 }
2614 break;
2615 case LTTNG_DOMAIN_UST:
2616 nb_events = ust_app_list_events(events);
2617 if (nb_events < 0) {
2618 ret = LTTNG_ERR_UST_LIST_FAIL;
2619 goto error;
2620 }
2621 break;
2622 case LTTNG_DOMAIN_LOG4J:
2623 case LTTNG_DOMAIN_JUL:
2624 case LTTNG_DOMAIN_PYTHON:
2625 nb_events = agent_list_events(events, domain);
2626 if (nb_events < 0) {
2627 ret = LTTNG_ERR_UST_LIST_FAIL;
2628 goto error;
2629 }
2630 break;
2631 default:
2632 ret = LTTNG_ERR_UND;
2633 goto error;
2634 }
2635
2636 return nb_events;
2637
2638 error:
2639 /* Return negative value to differentiate return code */
2640 return -ret;
2641 }
2642
2643 /*
2644 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2645 */
2646 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2647 struct lttng_event_field **fields)
2648 {
2649 int ret;
2650 ssize_t nb_fields = 0;
2651
2652 switch (domain) {
2653 case LTTNG_DOMAIN_UST:
2654 nb_fields = ust_app_list_event_fields(fields);
2655 if (nb_fields < 0) {
2656 ret = LTTNG_ERR_UST_LIST_FAIL;
2657 goto error;
2658 }
2659 break;
2660 case LTTNG_DOMAIN_KERNEL:
2661 default: /* fall-through */
2662 ret = LTTNG_ERR_UND;
2663 goto error;
2664 }
2665
2666 return nb_fields;
2667
2668 error:
2669 /* Return negative value to differentiate return code */
2670 return -ret;
2671 }
2672
2673 ssize_t cmd_list_syscalls(struct lttng_event **events)
2674 {
2675 return syscall_table_list(events);
2676 }
2677
2678 /*
2679 * Command LTTNG_START_TRACE processed by the client thread.
2680 *
2681 * Called with session mutex held.
2682 */
2683 int cmd_start_trace(struct ltt_session *session)
2684 {
2685 enum lttng_error_code ret;
2686 unsigned long nb_chan = 0;
2687 struct ltt_kernel_session *ksession;
2688 struct ltt_ust_session *usess;
2689 const bool session_rotated_after_last_stop =
2690 session->rotated_after_last_stop;
2691 const bool session_cleared_after_last_stop =
2692 session->cleared_after_last_stop;
2693
2694 assert(session);
2695
2696 /* Ease our life a bit ;) */
2697 ksession = session->kernel_session;
2698 usess = session->ust_session;
2699
2700 /* Is the session already started? */
2701 if (session->active) {
2702 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2703 /* Perform nothing */
2704 goto end;
2705 }
2706
2707 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING &&
2708 !session->current_trace_chunk) {
2709 /*
2710 * A rotation was launched while the session was stopped and
2711 * it has not been completed yet. It is not possible to start
2712 * the session since starting the session here would require a
2713 * rotation from "NULL" to a new trace chunk. That rotation
2714 * would overlap with the ongoing rotation, which is not
2715 * supported.
2716 */
2717 WARN("Refusing to start session \"%s\" as a rotation launched after the last \"stop\" is still ongoing",
2718 session->name);
2719 ret = LTTNG_ERR_ROTATION_PENDING;
2720 goto error;
2721 }
2722
2723 /*
2724 * Starting a session without channel is useless since after that it's not
2725 * possible to enable channel thus inform the client.
2726 */
2727 if (usess && usess->domain_global.channels) {
2728 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2729 }
2730 if (ksession) {
2731 nb_chan += ksession->channel_count;
2732 }
2733 if (!nb_chan) {
2734 ret = LTTNG_ERR_NO_CHANNEL;
2735 goto error;
2736 }
2737
2738 session->active = 1;
2739 session->rotated_after_last_stop = false;
2740 session->cleared_after_last_stop = false;
2741 if (session->output_traces && !session->current_trace_chunk) {
2742 if (!session->has_been_started) {
2743 struct lttng_trace_chunk *trace_chunk;
2744
2745 DBG("Creating initial trace chunk of session \"%s\"",
2746 session->name);
2747 trace_chunk = session_create_new_trace_chunk(
2748 session, NULL, NULL, NULL);
2749 if (!trace_chunk) {
2750 ret = LTTNG_ERR_CREATE_DIR_FAIL;
2751 goto error;
2752 }
2753 assert(!session->current_trace_chunk);
2754 ret = session_set_trace_chunk(session, trace_chunk,
2755 NULL);
2756 lttng_trace_chunk_put(trace_chunk);
2757 if (ret) {
2758 ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
2759 goto error;
2760 }
2761 } else {
2762 DBG("Rotating session \"%s\" from its current \"NULL\" trace chunk to a new chunk",
2763 session->name);
2764 /*
2765 * Rotate existing streams into the new chunk.
2766 * This is a "quiet" rotation has no client has
2767 * explicitly requested this operation.
2768 *
2769 * There is also no need to wait for the rotation
2770 * to complete as it will happen immediately. No data
2771 * was produced as the session was stopped, so the
2772 * rotation should happen on reception of the command.
2773 */
2774 ret = cmd_rotate_session(session, NULL, true,
2775 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
2776 if (ret != LTTNG_OK) {
2777 goto error;
2778 }
2779 }
2780 }
2781
2782 /* Kernel tracing */
2783 if (ksession != NULL) {
2784 DBG("Start kernel tracing session %s", session->name);
2785 ret = start_kernel_session(ksession);
2786 if (ret != LTTNG_OK) {
2787 goto error;
2788 }
2789 }
2790
2791 /* Flag session that trace should start automatically */
2792 if (usess) {
2793 int int_ret = ust_app_start_trace_all(usess);
2794
2795 if (int_ret < 0) {
2796 ret = LTTNG_ERR_UST_START_FAIL;
2797 goto error;
2798 }
2799 }
2800
2801 /*
2802 * Clear the flag that indicates that a rotation was done while the
2803 * session was stopped.
2804 */
2805 session->rotated_after_last_stop = false;
2806
2807 if (session->rotate_timer_period) {
2808 int int_ret = timer_session_rotation_schedule_timer_start(
2809 session, session->rotate_timer_period);
2810
2811 if (int_ret < 0) {
2812 ERR("Failed to enable rotate timer");
2813 ret = LTTNG_ERR_UNK;
2814 goto error;
2815 }
2816 }
2817
2818 ret = LTTNG_OK;
2819
2820 error:
2821 if (ret == LTTNG_OK) {
2822 /* Flag this after a successful start. */
2823 session->has_been_started |= 1;
2824 } else {
2825 session->active = 0;
2826 /* Restore initial state on error. */
2827 session->rotated_after_last_stop =
2828 session_rotated_after_last_stop;
2829 session->cleared_after_last_stop =
2830 session_cleared_after_last_stop;
2831 }
2832 end:
2833 return ret;
2834 }
2835
2836 /*
2837 * Command LTTNG_STOP_TRACE processed by the client thread.
2838 */
2839 int cmd_stop_trace(struct ltt_session *session)
2840 {
2841 int ret;
2842 struct ltt_kernel_session *ksession;
2843 struct ltt_ust_session *usess;
2844
2845 assert(session);
2846
2847 DBG("Begin stop session \"%s\" (id %" PRIu64 ")", session->name, session->id);
2848 /* Short cut */
2849 ksession = session->kernel_session;
2850 usess = session->ust_session;
2851
2852 /* Session is not active. Skip everythong and inform the client. */
2853 if (!session->active) {
2854 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2855 goto error;
2856 }
2857
2858 ret = stop_kernel_session(ksession);
2859 if (ret != LTTNG_OK) {
2860 goto error;
2861 }
2862
2863 if (usess && usess->active) {
2864 ret = ust_app_stop_trace_all(usess);
2865 if (ret < 0) {
2866 ret = LTTNG_ERR_UST_STOP_FAIL;
2867 goto error;
2868 }
2869 }
2870
2871 DBG("Completed stop session \"%s\" (id %" PRIu64 ")", session->name,
2872 session->id);
2873 /* Flag inactive after a successful stop. */
2874 session->active = 0;
2875 ret = LTTNG_OK;
2876
2877 error:
2878 return ret;
2879 }
2880
2881 /*
2882 * Set the base_path of the session only if subdir of a control uris is set.
2883 * Return LTTNG_OK on success, otherwise LTTNG_ERR_*.
2884 */
2885 static int set_session_base_path_from_uris(struct ltt_session *session,
2886 size_t nb_uri,
2887 struct lttng_uri *uris)
2888 {
2889 int ret;
2890 size_t i;
2891
2892 for (i = 0; i < nb_uri; i++) {
2893 if (uris[i].stype != LTTNG_STREAM_CONTROL ||
2894 uris[i].subdir[0] == '\0') {
2895 /* Not interested in these URIs */
2896 continue;
2897 }
2898
2899 if (session->base_path != NULL) {
2900 free(session->base_path);
2901 session->base_path = NULL;
2902 }
2903
2904 /* Set session base_path */
2905 session->base_path = strdup(uris[i].subdir);
2906 if (!session->base_path) {
2907 PERROR("Failed to copy base path \"%s\" to session \"%s\"",
2908 uris[i].subdir, session->name);
2909 ret = LTTNG_ERR_NOMEM;
2910 goto error;
2911 }
2912 DBG2("Setting base path \"%s\" for session \"%s\"",
2913 session->base_path, session->name);
2914 }
2915 ret = LTTNG_OK;
2916 error:
2917 return ret;
2918 }
2919
2920 /*
2921 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2922 */
2923 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2924 struct lttng_uri *uris)
2925 {
2926 int ret, i;
2927 struct ltt_kernel_session *ksess = session->kernel_session;
2928 struct ltt_ust_session *usess = session->ust_session;
2929
2930 assert(session);
2931 assert(uris);
2932 assert(nb_uri > 0);
2933
2934 /* Can't set consumer URI if the session is active. */
2935 if (session->active) {
2936 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2937 goto error;
2938 }
2939
2940 /*
2941 * Set the session base path if any. This is done inside
2942 * cmd_set_consumer_uri to preserve backward compatibility of the
2943 * previous session creation api vs the session descriptor api.
2944 */
2945 ret = set_session_base_path_from_uris(session, nb_uri, uris);
2946 if (ret != LTTNG_OK) {
2947 goto error;
2948 }
2949
2950 /* Set the "global" consumer URIs */
2951 for (i = 0; i < nb_uri; i++) {
2952 ret = add_uri_to_consumer(session, session->consumer, &uris[i],
2953 LTTNG_DOMAIN_NONE);
2954 if (ret != LTTNG_OK) {
2955 goto error;
2956 }
2957 }
2958
2959 /* Set UST session URIs */
2960 if (session->ust_session) {
2961 for (i = 0; i < nb_uri; i++) {
2962 ret = add_uri_to_consumer(session,
2963 session->ust_session->consumer,
2964 &uris[i], LTTNG_DOMAIN_UST);
2965 if (ret != LTTNG_OK) {
2966 goto error;
2967 }
2968 }
2969 }
2970
2971 /* Set kernel session URIs */
2972 if (session->kernel_session) {
2973 for (i = 0; i < nb_uri; i++) {
2974 ret = add_uri_to_consumer(session,
2975 session->kernel_session->consumer,
2976 &uris[i], LTTNG_DOMAIN_KERNEL);
2977 if (ret != LTTNG_OK) {
2978 goto error;
2979 }
2980 }
2981 }
2982
2983 /*
2984 * Make sure to set the session in output mode after we set URI since a
2985 * session can be created without URL (thus flagged in no output mode).
2986 */
2987 session->output_traces = 1;
2988 if (ksess) {
2989 ksess->output_traces = 1;
2990 }
2991
2992 if (usess) {
2993 usess->output_traces = 1;
2994 }
2995
2996 /* All good! */
2997 ret = LTTNG_OK;
2998
2999 error:
3000 return ret;
3001 }
3002
3003 static
3004 enum lttng_error_code set_session_output_from_descriptor(
3005 struct ltt_session *session,
3006 const struct lttng_session_descriptor *descriptor)
3007 {
3008 int ret;
3009 enum lttng_error_code ret_code = LTTNG_OK;
3010 enum lttng_session_descriptor_type session_type =
3011 lttng_session_descriptor_get_type(descriptor);
3012 enum lttng_session_descriptor_output_type output_type =
3013 lttng_session_descriptor_get_output_type(descriptor);
3014 struct lttng_uri uris[2] = {};
3015 size_t uri_count = 0;
3016
3017 switch (output_type) {
3018 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NONE:
3019 goto end;
3020 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_LOCAL:
3021 lttng_session_descriptor_get_local_output_uri(descriptor,
3022 &uris[0]);
3023 uri_count = 1;
3024 break;
3025 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NETWORK:
3026 lttng_session_descriptor_get_network_output_uris(descriptor,
3027 &uris[0], &uris[1]);
3028 uri_count = 2;
3029 break;
3030 default:
3031 ret_code = LTTNG_ERR_INVALID;
3032 goto end;
3033 }
3034
3035 switch (session_type) {
3036 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
3037 {
3038 struct snapshot_output *new_output = NULL;
3039
3040 new_output = snapshot_output_alloc();
3041 if (!new_output) {
3042 ret_code = LTTNG_ERR_NOMEM;
3043 goto end;
3044 }
3045
3046 ret = snapshot_output_init_with_uri(session,
3047 DEFAULT_SNAPSHOT_MAX_SIZE,
3048 NULL, uris, uri_count, session->consumer,
3049 new_output, &session->snapshot);
3050 if (ret < 0) {
3051 ret_code = (ret == -ENOMEM) ?
3052 LTTNG_ERR_NOMEM : LTTNG_ERR_INVALID;
3053 snapshot_output_destroy(new_output);
3054 goto end;
3055 }
3056 snapshot_add_output(&session->snapshot, new_output);
3057 break;
3058 }
3059 case LTTNG_SESSION_DESCRIPTOR_TYPE_REGULAR:
3060 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3061 {
3062 ret_code = cmd_set_consumer_uri(session, uri_count, uris);
3063 break;
3064 }
3065 default:
3066 ret_code = LTTNG_ERR_INVALID;
3067 goto end;
3068 }
3069 end:
3070 return ret_code;
3071 }
3072
3073 static
3074 enum lttng_error_code cmd_create_session_from_descriptor(
3075 struct lttng_session_descriptor *descriptor,
3076 const lttng_sock_cred *creds,
3077 const char *home_path)
3078 {
3079 int ret;
3080 enum lttng_error_code ret_code;
3081 const char *session_name;
3082 struct ltt_session *new_session = NULL;
3083 enum lttng_session_descriptor_status descriptor_status;
3084
3085 session_lock_list();
3086 if (home_path) {
3087 if (*home_path != '/') {
3088 ERR("Home path provided by client is not absolute");
3089 ret_code = LTTNG_ERR_INVALID;
3090 goto end;
3091 }
3092 }
3093
3094 descriptor_status = lttng_session_descriptor_get_session_name(
3095 descriptor, &session_name);
3096 switch (descriptor_status) {
3097 case LTTNG_SESSION_DESCRIPTOR_STATUS_OK:
3098 break;
3099 case LTTNG_SESSION_DESCRIPTOR_STATUS_UNSET:
3100 session_name = NULL;
3101 break;
3102 default:
3103 ret_code = LTTNG_ERR_INVALID;
3104 goto end;
3105 }
3106
3107 ret_code = session_create(session_name, creds->uid, creds->gid,
3108 &new_session);
3109 if (ret_code != LTTNG_OK) {
3110 goto end;
3111 }
3112
3113 if (!session_name) {
3114 ret = lttng_session_descriptor_set_session_name(descriptor,
3115 new_session->name);
3116 if (ret) {
3117 ret_code = LTTNG_ERR_SESSION_FAIL;
3118 goto end;
3119 }
3120 }
3121
3122 if (!lttng_session_descriptor_is_output_destination_initialized(
3123 descriptor)) {
3124 /*
3125 * Only include the session's creation time in the output
3126 * destination if the name of the session itself was
3127 * not auto-generated.
3128 */
3129 ret_code = lttng_session_descriptor_set_default_output(
3130 descriptor,
3131 session_name ? &new_session->creation_time : NULL,
3132 home_path);
3133 if (ret_code != LTTNG_OK) {
3134 goto end;
3135 }
3136 } else {
3137 new_session->has_user_specified_directory =
3138 lttng_session_descriptor_has_output_directory(
3139 descriptor);
3140 }
3141
3142 switch (lttng_session_descriptor_get_type(descriptor)) {
3143 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
3144 new_session->snapshot_mode = 1;
3145 break;
3146 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3147 new_session->live_timer =
3148 lttng_session_descriptor_live_get_timer_interval(
3149 descriptor);
3150 break;
3151 default:
3152 break;
3153 }
3154
3155 ret_code = set_session_output_from_descriptor(new_session, descriptor);
3156 if (ret_code != LTTNG_OK) {
3157 goto end;
3158 }
3159 new_session->consumer->enabled = 1;
3160 ret_code = LTTNG_OK;
3161 end:
3162 /* Release reference provided by the session_create function. */
3163 session_put(new_session);
3164 if (ret_code != LTTNG_OK && new_session) {
3165 /* Release the global reference on error. */
3166 session_destroy(new_session);
3167 }
3168 session_unlock_list();
3169 return ret_code;
3170 }
3171
3172 enum lttng_error_code cmd_create_session(struct command_ctx *cmd_ctx, int sock,
3173 struct lttng_session_descriptor **return_descriptor)
3174 {
3175 int ret;
3176 size_t payload_size;
3177 struct lttng_dynamic_buffer payload;
3178 struct lttng_buffer_view home_dir_view;
3179 struct lttng_buffer_view session_descriptor_view;
3180 struct lttng_session_descriptor *session_descriptor = NULL;
3181 enum lttng_error_code ret_code;
3182
3183 lttng_dynamic_buffer_init(&payload);
3184 if (cmd_ctx->lsm->u.create_session.home_dir_size >=
3185 LTTNG_PATH_MAX) {
3186 ret_code = LTTNG_ERR_INVALID;
3187 goto error;
3188 }
3189 if (cmd_ctx->lsm->u.create_session.session_descriptor_size >
3190 LTTNG_SESSION_DESCRIPTOR_MAX_LEN) {
3191 ret_code = LTTNG_ERR_INVALID;
3192 goto error;
3193 }
3194
3195 payload_size = cmd_ctx->lsm->u.create_session.home_dir_size +
3196 cmd_ctx->lsm->u.create_session.session_descriptor_size;
3197 ret = lttng_dynamic_buffer_set_size(&payload, payload_size);
3198 if (ret) {
3199 ret_code = LTTNG_ERR_NOMEM;
3200 goto error;
3201 }
3202
3203 ret = lttcomm_recv_unix_sock(sock, payload.data, payload.size);
3204 if (ret <= 0) {
3205 ERR("Reception of session descriptor failed, aborting.");
3206 ret_code = LTTNG_ERR_SESSION_FAIL;
3207 goto error;
3208 }
3209
3210 home_dir_view = lttng_buffer_view_from_dynamic_buffer(
3211 &payload,
3212 0,
3213 cmd_ctx->lsm->u.create_session.home_dir_size);
3214 session_descriptor_view = lttng_buffer_view_from_dynamic_buffer(
3215 &payload,
3216 cmd_ctx->lsm->u.create_session.home_dir_size,
3217 cmd_ctx->lsm->u.create_session.session_descriptor_size);
3218
3219 ret = lttng_session_descriptor_create_from_buffer(
3220 &session_descriptor_view, &session_descriptor);
3221 if (ret < 0) {
3222 ERR("Failed to create session descriptor from payload of \"create session\" command");
3223 ret_code = LTTNG_ERR_INVALID;
3224 goto error;
3225 }
3226
3227 /*
3228 * Sets the descriptor's auto-generated properties (name, output) if
3229 * needed.
3230 */
3231 ret_code = cmd_create_session_from_descriptor(session_descriptor,
3232 &cmd_ctx->creds,
3233 home_dir_view.size ? home_dir_view.data : NULL);
3234 if (ret_code != LTTNG_OK) {
3235 goto error;
3236 }
3237
3238 ret_code = LTTNG_OK;
3239 *return_descriptor = session_descriptor;
3240 session_descriptor = NULL;
3241 error:
3242 lttng_dynamic_buffer_reset(&payload);
3243 lttng_session_descriptor_destroy(session_descriptor);
3244 return ret_code;
3245 }
3246
3247 static
3248 void cmd_destroy_session_reply(const struct ltt_session *session,
3249 void *_reply_context)
3250 {
3251 int ret;
3252 ssize_t comm_ret;
3253 const struct cmd_destroy_session_reply_context *reply_context =
3254 _reply_context;
3255 struct lttng_dynamic_buffer payload;
3256 struct lttcomm_session_destroy_command_header cmd_header;
3257 struct lttng_trace_archive_location *location = NULL;
3258 struct lttcomm_lttng_msg llm = {
3259 .cmd_type = LTTNG_DESTROY_SESSION,
3260 .ret_code = reply_context->destruction_status,
3261 .pid = UINT32_MAX,
3262 .cmd_header_size =
3263 sizeof(struct lttcomm_session_destroy_command_header),
3264 .data_size = 0,
3265 };
3266 size_t payload_size_before_location;
3267
3268 lttng_dynamic_buffer_init(&payload);
3269
3270 ret = lttng_dynamic_buffer_append(&payload, &llm, sizeof(llm));
3271 if (ret) {
3272 ERR("Failed to append session destruction message");
3273 goto error;
3274 }
3275
3276 cmd_header.rotation_state =
3277 (int32_t) (reply_context->implicit_rotation_on_destroy ?
3278 session->rotation_state :
3279 LTTNG_ROTATION_STATE_NO_ROTATION);
3280 ret = lttng_dynamic_buffer_append(&payload, &cmd_header,
3281 sizeof(cmd_header));
3282 if (ret) {
3283 ERR("Failed to append session destruction command header");
3284 goto error;
3285 }
3286
3287 if (!reply_context->implicit_rotation_on_destroy) {
3288 DBG("No implicit rotation performed during the destruction of session \"%s\", sending reply",
3289 session->name);
3290 goto send_reply;
3291 }
3292 if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED) {
3293 DBG("Rotation state of session \"%s\" is not \"completed\", sending session destruction reply",
3294 session->name);
3295 goto send_reply;
3296 }
3297
3298 location = session_get_trace_archive_location(session);
3299 if (!location) {
3300 ERR("Failed to get the location of the trace archive produced during the destruction of session \"%s\"",
3301 session->name);
3302 goto error;
3303 }
3304
3305 payload_size_before_location = payload.size;
3306 comm_ret = lttng_trace_archive_location_serialize(location,
3307 &payload);
3308 if (comm_ret < 0) {
3309 ERR("Failed to serialize the location of the trace archive produced during the destruction of session \"%s\"",
3310 session->name);
3311 goto error;
3312 }
3313 /* Update the message to indicate the location's length. */
3314 ((struct lttcomm_lttng_msg *) payload.data)->data_size =
3315 payload.size - payload_size_before_location;
3316 send_reply:
3317 comm_ret = lttcomm_send_unix_sock(reply_context->reply_sock_fd,
3318 payload.data, payload.size);
3319 if (comm_ret != (ssize_t) payload.size) {
3320 ERR("Failed to send result of the destruction of session \"%s\" to client",
3321 session->name);
3322 }
3323 error:
3324 ret = close(reply_context->reply_sock_fd);
3325 if (ret) {
3326 PERROR("Failed to close client socket in deferred session destroy reply");
3327 }
3328 lttng_dynamic_buffer_reset(&payload);
3329 free(_reply_context);
3330 }
3331
3332 /*
3333 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3334 *
3335 * Called with session lock held.
3336 */
3337 int cmd_destroy_session(struct ltt_session *session,
3338 struct notification_thread_handle *notification_thread_handle,
3339 int *sock_fd)
3340 {
3341 int ret;
3342 enum lttng_error_code destruction_last_error = LTTNG_OK;
3343 struct cmd_destroy_session_reply_context *reply_context = NULL;
3344
3345 if (sock_fd) {
3346 reply_context = zmalloc(sizeof(*reply_context));
3347 if (!reply_context) {
3348 ret = LTTNG_ERR_NOMEM;
3349 goto end;
3350 }
3351 reply_context->reply_sock_fd = *sock_fd;
3352 }
3353
3354 /* Safety net */
3355 assert(session);
3356
3357 DBG("Begin destroy session %s (id %" PRIu64 ")", session->name,
3358 session->id);
3359 if (session->active) {
3360 DBG("Session \"%s\" is active, attempting to stop it before destroying it",
3361 session->name);
3362 ret = cmd_stop_trace(session);
3363 if (ret != LTTNG_OK && ret != LTTNG_ERR_TRACE_ALREADY_STOPPED) {
3364 /* Carry on with the destruction of the session. */
3365 ERR("Failed to stop session \"%s\" as part of its destruction: %s",
3366 session->name, lttng_strerror(-ret));
3367 destruction_last_error = ret;
3368 }
3369 }
3370
3371 if (session->rotation_schedule_timer_enabled) {
3372 if (timer_session_rotation_schedule_timer_stop(
3373 session)) {
3374 ERR("Failed to stop the \"rotation schedule\" timer of session %s",
3375 session->name);
3376 destruction_last_error = LTTNG_ERR_TIMER_STOP_ERROR;
3377 }
3378 }
3379
3380 if (session->rotate_size) {
3381 unsubscribe_session_consumed_size_rotation(session, notification_thread_handle);
3382 session->rotate_size = 0;
3383 }
3384
3385 if (session->rotated && session->current_trace_chunk && session->output_traces) {
3386 /*
3387 * Perform a last rotation on destruction if rotations have
3388 * occurred during the session's lifetime.
3389 */
3390 ret = cmd_rotate_session(session, NULL, false,
3391 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
3392 if (ret != LTTNG_OK) {
3393 ERR("Failed to perform an implicit rotation as part of the destruction of session \"%s\": %s",
3394 session->name, lttng_strerror(-ret));
3395 destruction_last_error = -ret;
3396 }
3397 if (reply_context) {
3398 reply_context->implicit_rotation_on_destroy = true;
3399 }
3400 } else if (session->has_been_started && session->current_trace_chunk) {
3401 /*
3402 * The user has not triggered a session rotation. However, to
3403 * ensure all data has been consumed, the session is rotated
3404 * to a 'null' trace chunk before it is destroyed.
3405 *
3406 * This is a "quiet" rotation meaning that no notification is
3407 * emitted and no renaming of the current trace chunk takes
3408 * place.
3409 */
3410 ret = cmd_rotate_session(session, NULL, true,
3411 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
3412 /*
3413 * Rotation operations may not be supported by the kernel
3414 * tracer. Hence, do not consider this implicit rotation as
3415 * a session destruction error. The library has already stopped
3416 * the session and waited for pending data; there is nothing
3417 * left to do but complete the destruction of the session.
3418 */
3419 if (ret != LTTNG_OK &&
3420 ret != -LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL) {
3421 ERR("Failed to perform a quiet rotation as part of the destruction of session \"%s\": %s",
3422 session->name, lttng_strerror(ret));
3423 destruction_last_error = -ret;
3424 }
3425 }
3426
3427 if (session->shm_path[0]) {
3428 /*
3429 * When a session is created with an explicit shm_path,
3430 * the consumer daemon will create its shared memory files
3431 * at that location and will *not* unlink them. This is normal
3432 * as the intention of that feature is to make it possible
3433 * to retrieve the content of those files should a crash occur.
3434 *
3435 * To ensure the content of those files can be used, the
3436 * sessiond daemon will replicate the content of the metadata
3437 * cache in a metadata file.
3438 *
3439 * On clean-up, it is expected that the consumer daemon will
3440 * unlink the shared memory files and that the session daemon
3441 * will unlink the metadata file. Then, the session's directory
3442 * in the shm path can be removed.
3443 *
3444 * Unfortunately, a flaw in the design of the sessiond's and
3445 * consumerd's tear down of channels makes it impossible to
3446 * determine when the sessiond _and_ the consumerd have both
3447 * destroyed their representation of a channel. For one, the
3448 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3449 * callbacks in both daemons.
3450 *
3451 * However, it is also impossible for the sessiond to know when
3452 * the consumer daemon is done destroying its channel(s) since
3453 * it occurs as a reaction to the closing of the channel's file
3454 * descriptor. There is no resulting communication initiated
3455 * from the consumerd to the sessiond to confirm that the
3456 * operation is completed (and was successful).
3457 *
3458 * Until this is all fixed, the session daemon checks for the
3459 * removal of the session's shm path which makes it possible
3460 * to safely advertise a session as having been destroyed.
3461 *
3462 * Prior to this fix, it was not possible to reliably save
3463 * a session making use of the --shm-path option, destroy it,
3464 * and load it again. This is because the creation of the
3465 * session would fail upon seeing the session's shm path
3466 * already in existence.
3467 *
3468 * Note that none of the error paths in the check for the
3469 * directory's existence return an error. This is normal
3470 * as there isn't much that can be done. The session will
3471 * be destroyed properly, except that we can't offer the
3472 * guarantee that the same session can be re-created.
3473 */
3474 current_completion_handler = &destroy_completion_handler.handler;
3475 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3476 session->shm_path,
3477 sizeof(destroy_completion_handler.shm_path));
3478 assert(!ret);
3479 }
3480
3481 /*
3482 * The session is destroyed. However, note that the command context
3483 * still holds a reference to the session, thus delaying its destruction
3484 * _at least_ up to the point when that reference is released.
3485 */
3486 session_destroy(session);
3487 if (reply_context) {
3488 reply_context->destruction_status = destruction_last_error;
3489 ret = session_add_destroy_notifier(session,
3490 cmd_destroy_session_reply,
3491 (void *) reply_context);
3492 if (ret) {
3493 ret = LTTNG_ERR_FATAL;
3494 goto end;
3495 } else {
3496 *sock_fd = -1;
3497 }
3498 }
3499 ret = LTTNG_OK;
3500 end:
3501 return ret;
3502 }
3503
3504 /*
3505 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3506 */
3507 int cmd_register_consumer(struct ltt_session *session,
3508 enum lttng_domain_type domain, const char *sock_path,
3509 struct consumer_data *cdata)
3510 {
3511 int ret, sock;
3512 struct consumer_socket *socket = NULL;
3513
3514 assert(session);
3515 assert(cdata);
3516 assert(sock_path);
3517
3518 switch (domain) {
3519 case LTTNG_DOMAIN_KERNEL:
3520 {
3521 struct ltt_kernel_session *ksess = session->kernel_session;
3522
3523 assert(ksess);
3524
3525 /* Can't register a consumer if there is already one */
3526 if (ksess->consumer_fds_sent != 0) {
3527 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3528 goto error;
3529 }
3530
3531 sock = lttcomm_connect_unix_sock(sock_path);
3532 if (sock < 0) {
3533 ret = LTTNG_ERR_CONNECT_FAIL;
3534 goto error;
3535 }
3536 cdata->cmd_sock = sock;
3537
3538 socket = consumer_allocate_socket(&cdata->cmd_sock);
3539 if (socket == NULL) {
3540 ret = close(sock);
3541 if (ret < 0) {
3542 PERROR("close register consumer");
3543 }
3544 cdata->cmd_sock = -1;
3545 ret = LTTNG_ERR_FATAL;
3546 goto error;
3547 }
3548
3549 socket->lock = zmalloc(sizeof(pthread_mutex_t));
3550 if (socket->lock == NULL) {
3551 PERROR("zmalloc pthread mutex");
3552 ret = LTTNG_ERR_FATAL;
3553 goto error;
3554 }
3555 pthread_mutex_init(socket->lock, NULL);
3556 socket->registered = 1;
3557
3558 rcu_read_lock();
3559 consumer_add_socket(socket, ksess->consumer);
3560 rcu_read_unlock();
3561
3562 pthread_mutex_lock(&cdata->pid_mutex);
3563 cdata->pid = -1;
3564 pthread_mutex_unlock(&cdata->pid_mutex);
3565
3566 break;
3567 }
3568 default:
3569 /* TODO: Userspace tracing */
3570 ret = LTTNG_ERR_UND;
3571 goto error;
3572 }
3573
3574 return LTTNG_OK;
3575
3576 error:
3577 if (socket) {
3578 consumer_destroy_socket(socket);
3579 }
3580 return ret;
3581 }
3582
3583 /*
3584 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3585 */
3586 ssize_t cmd_list_domains(struct ltt_session *session,
3587 struct lttng_domain **domains)
3588 {
3589 int ret, index = 0;
3590 ssize_t nb_dom = 0;
3591 struct agent *agt;
3592 struct lttng_ht_iter iter;
3593
3594 if (session->kernel_session != NULL) {
3595 DBG3("Listing domains found kernel domain");
3596 nb_dom++;
3597 }
3598
3599 if (session->ust_session != NULL) {
3600 DBG3("Listing domains found UST global domain");
3601 nb_dom++;
3602
3603 rcu_read_lock();
3604 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3605 agt, node.node) {
3606 if (agt->being_used) {
3607 nb_dom++;
3608 }
3609 }
3610 rcu_read_unlock();
3611 }
3612
3613 if (!nb_dom) {
3614 goto end;
3615 }
3616
3617 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3618 if (*domains == NULL) {
3619 ret = LTTNG_ERR_FATAL;
3620 goto error;
3621 }
3622
3623 if (session->kernel_session != NULL) {
3624 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3625
3626 /* Kernel session buffer type is always GLOBAL */
3627 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3628
3629 index++;
3630 }
3631
3632 if (session->ust_session != NULL) {
3633 (*domains)[index].type = LTTNG_DOMAIN_UST;
3634 (*domains)[index].buf_type = session->ust_session->buffer_type;
3635 index++;
3636
3637 rcu_read_lock();
3638 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3639 agt, node.node) {
3640 if (agt->being_used) {
3641 (*domains)[index].type = agt->domain;
3642 (*domains)[index].buf_type = session->ust_session->buffer_type;
3643 index++;
3644 }
3645 }
3646 rcu_read_unlock();
3647 }
3648 end:
3649 return nb_dom;
3650
3651 error:
3652 /* Return negative value to differentiate return code */
3653 return -ret;
3654 }
3655
3656
3657 /*
3658 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3659 */
3660 ssize_t cmd_list_channels(enum lttng_domain_type domain,
3661 struct ltt_session *session, struct lttng_channel **channels)
3662 {
3663 ssize_t nb_chan = 0, payload_size = 0, ret;
3664
3665 switch (domain) {
3666 case LTTNG_DOMAIN_KERNEL:
3667 if (session->kernel_session != NULL) {
3668 nb_chan = session->kernel_session->channel_count;
3669 }
3670 DBG3("Number of kernel channels %zd", nb_chan);
3671 if (nb_chan <= 0) {
3672 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
3673 goto end;
3674 }
3675 break;
3676 case LTTNG_DOMAIN_UST:
3677 if (session->ust_session != NULL) {
3678 rcu_read_lock();
3679 nb_chan = lttng_ht_get_count(
3680 session->ust_session->domain_global.channels);
3681 rcu_read_unlock();
3682 }
3683 DBG3("Number of UST global channels %zd", nb_chan);
3684 if (nb_chan < 0) {
3685 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
3686 goto end;
3687 }
3688 break;
3689 default:
3690 ret = -LTTNG_ERR_UND;
3691 goto end;
3692 }
3693
3694 if (nb_chan > 0) {
3695 const size_t channel_size = sizeof(struct lttng_channel) +
3696 sizeof(struct lttng_channel_extended);
3697 struct lttng_channel_extended *channel_exts;
3698
3699 payload_size = nb_chan * channel_size;
3700 *channels = zmalloc(payload_size);
3701 if (*channels == NULL) {
3702 ret = -LTTNG_ERR_FATAL;
3703 goto end;
3704 }
3705
3706 channel_exts = ((void *) *channels) +
3707 (nb_chan * sizeof(struct lttng_channel));
3708 ret = list_lttng_channels(domain, session, *channels, channel_exts);
3709 if (ret != LTTNG_OK) {
3710 free(*channels);
3711 *channels = NULL;
3712 goto end;
3713 }
3714 } else {
3715 *channels = NULL;
3716 }
3717
3718 ret = payload_size;
3719 end:
3720 return ret;
3721 }
3722
3723 /*
3724 * Command LTTNG_LIST_EVENTS processed by the client thread.
3725 */
3726 ssize_t cmd_list_events(enum lttng_domain_type domain,
3727 struct ltt_session *session, char *channel_name,
3728 struct lttng_event **events, size_t *total_size)
3729 {
3730 int ret = 0;
3731 ssize_t nb_event = 0;
3732
3733 switch (domain) {
3734 case LTTNG_DOMAIN_KERNEL:
3735 if (session->kernel_session != NULL) {
3736 nb_event = list_lttng_kernel_events(channel_name,
3737 session->kernel_session, events,
3738 total_size);
3739 }
3740 break;
3741 case LTTNG_DOMAIN_UST:
3742 {
3743 if (session->ust_session != NULL) {
3744 nb_event = list_lttng_ust_global_events(channel_name,
3745 &session->ust_session->domain_global, events,
3746 total_size);
3747 }
3748 break;
3749 }
3750 case LTTNG_DOMAIN_LOG4J:
3751 case LTTNG_DOMAIN_JUL:
3752 case LTTNG_DOMAIN_PYTHON:
3753 if (session->ust_session) {
3754 struct lttng_ht_iter iter;
3755 struct agent *agt;
3756
3757 rcu_read_lock();
3758 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3759 &iter.iter, agt, node.node) {
3760 if (agt->domain == domain) {
3761 nb_event = list_lttng_agent_events(
3762 agt, events,
3763 total_size);
3764 break;
3765 }
3766 }
3767 rcu_read_unlock();
3768 }
3769 break;
3770 default:
3771 ret = LTTNG_ERR_UND;
3772 goto error;
3773 }
3774
3775 return nb_event;
3776
3777 error:
3778 /* Return negative value to differentiate return code */
3779 return -ret;
3780 }
3781
3782 /*
3783 * Using the session list, filled a lttng_session array to send back to the
3784 * client for session listing.
3785 *
3786 * The session list lock MUST be acquired before calling this function. Use
3787 * session_lock_list() and session_unlock_list().
3788 */
3789 void cmd_list_lttng_sessions(struct lttng_session *sessions,
3790 size_t session_count, uid_t uid, gid_t gid)
3791 {
3792 int ret;
3793 unsigned int i = 0;
3794 struct ltt_session *session;
3795 struct ltt_session_list *list = session_get_list();
3796 struct lttng_session_extended *extended =
3797 (typeof(extended)) (&sessions[session_count]);
3798
3799 DBG("Getting all available session for UID %d GID %d",
3800 uid, gid);
3801 /*
3802 * Iterate over session list and append data after the control struct in
3803 * the buffer.
3804 */
3805 cds_list_for_each_entry(session, &list->head, list) {
3806 if (!session_get(session)) {
3807 continue;
3808 }
3809 /*
3810 * Only list the sessions the user can control.
3811 */
3812 if (!session_access_ok(session, uid, gid) ||
3813 session->destroyed) {
3814 session_put(session);
3815 continue;
3816 }
3817
3818 struct ltt_kernel_session *ksess = session->kernel_session;
3819 struct ltt_ust_session *usess = session->ust_session;
3820
3821 if (session->consumer->type == CONSUMER_DST_NET ||
3822 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3823 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3824 ret = build_network_session_path(sessions[i].path,
3825 sizeof(sessions[i].path), session);
3826 } else {
3827 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3828 session->consumer->dst.session_root_path);
3829 }
3830 if (ret < 0) {
3831 PERROR("snprintf session path");
3832 session_put(session);
3833 continue;
3834 }
3835
3836 strncpy(sessions[i].name, session->name, NAME_MAX);
3837 sessions[i].name[NAME_MAX - 1] = '\0';
3838 sessions[i].enabled = session->active;
3839 sessions[i].snapshot_mode = session->snapshot_mode;
3840 sessions[i].live_timer_interval = session->live_timer;
3841 extended[i].creation_time.value = (uint64_t) session->creation_time;
3842 extended[i].creation_time.is_set = 1;
3843 i++;
3844 session_put(session);
3845 }
3846 }
3847
3848 /*
3849 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3850 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3851 */
3852 int cmd_data_pending(struct ltt_session *session)
3853 {
3854 int ret;
3855 struct ltt_kernel_session *ksess = session->kernel_session;
3856 struct ltt_ust_session *usess = session->ust_session;
3857
3858 assert(session);
3859
3860 DBG("Data pending for session %s", session->name);
3861
3862 /* Session MUST be stopped to ask for data availability. */
3863 if (session->active) {
3864 ret = LTTNG_ERR_SESSION_STARTED;
3865 goto error;
3866 } else {
3867 /*
3868 * If stopped, just make sure we've started before else the above call
3869 * will always send that there is data pending.
3870 *
3871 * The consumer assumes that when the data pending command is received,
3872 * the trace has been started before or else no output data is written
3873 * by the streams which is a condition for data pending. So, this is
3874 * *VERY* important that we don't ask the consumer before a start
3875 * trace.
3876 */
3877 if (!session->has_been_started) {
3878 ret = 0;
3879 goto error;
3880 }
3881 }
3882
3883 /* A rotation is still pending, we have to wait. */
3884 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
3885 DBG("Rotate still pending for session %s", session->name);
3886 ret = 1;
3887 goto error;
3888 }
3889
3890 if (ksess && ksess->consumer) {
3891 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3892 if (ret == 1) {
3893 /* Data is still being extracted for the kernel. */
3894 goto error;
3895 }
3896 }
3897
3898 if (usess && usess->consumer) {
3899 ret = consumer_is_data_pending(usess->id, usess->consumer);
3900 if (ret == 1) {
3901 /* Data is still being extracted for the kernel. */
3902 goto error;
3903 }
3904 }
3905
3906 /* Data is ready to be read by a viewer */
3907 ret = 0;
3908
3909 error:
3910 return ret;
3911 }
3912
3913 /*
3914 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3915 *
3916 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3917 */
3918 int cmd_snapshot_add_output(struct ltt_session *session,
3919 const struct lttng_snapshot_output *output, uint32_t *id)
3920 {
3921 int ret;
3922 struct snapshot_output *new_output;
3923
3924 assert(session);
3925 assert(output);
3926
3927 DBG("Cmd snapshot add output for session %s", session->name);
3928
3929 /*
3930 * Can't create an output if the session is not set in no-output mode.
3931 */
3932 if (session->output_traces) {
3933 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3934 goto error;
3935 }
3936
3937 if (session->has_non_mmap_channel) {
3938 ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
3939 goto error;
3940 }
3941
3942 /* Only one output is allowed until we have the "tee" feature. */
3943 if (session->snapshot.nb_output == 1) {
3944 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3945 goto error;
3946 }
3947
3948 new_output = snapshot_output_alloc();
3949 if (!new_output) {
3950 ret = LTTNG_ERR_NOMEM;
3951 goto error;
3952 }
3953
3954 ret = snapshot_output_init(session, output->max_size, output->name,
3955 output->ctrl_url, output->data_url, session->consumer, new_output,
3956 &session->snapshot);
3957 if (ret < 0) {
3958 if (ret == -ENOMEM) {
3959 ret = LTTNG_ERR_NOMEM;
3960 } else {
3961 ret = LTTNG_ERR_INVALID;
3962 }
3963 goto free_error;
3964 }
3965
3966 rcu_read_lock();
3967 snapshot_add_output(&session->snapshot, new_output);
3968 if (id) {
3969 *id = new_output->id;
3970 }
3971 rcu_read_unlock();
3972
3973 return LTTNG_OK;
3974
3975 free_error:
3976 snapshot_output_destroy(new_output);
3977 error:
3978 return ret;
3979 }
3980
3981 /*
3982 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3983 *
3984 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3985 */
3986 int cmd_snapshot_del_output(struct ltt_session *session,
3987 const struct lttng_snapshot_output *output)
3988 {
3989 int ret;
3990 struct snapshot_output *sout = NULL;
3991
3992 assert(session);
3993 assert(output);
3994
3995 rcu_read_lock();
3996
3997 /*
3998 * Permission denied to create an output if the session is not
3999 * set in no output mode.
4000 */
4001 if (session->output_traces) {
4002 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4003 goto error;
4004 }
4005
4006 if (output->id) {
4007 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
4008 session->name);
4009 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
4010 } else if (*output->name != '\0') {
4011 DBG("Cmd snapshot del output name %s for session %s", output->name,
4012 session->name);
4013 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
4014 }
4015 if (!sout) {
4016 ret = LTTNG_ERR_INVALID;
4017 goto error;
4018 }
4019
4020 snapshot_delete_output(&session->snapshot, sout);
4021 snapshot_output_destroy(sout);
4022 ret = LTTNG_OK;
4023
4024 error:
4025 rcu_read_unlock();
4026 return ret;
4027 }
4028
4029 /*
4030 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
4031 *
4032 * If no output is available, outputs is untouched and 0 is returned.
4033 *
4034 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
4035 */
4036 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
4037 struct lttng_snapshot_output **outputs)
4038 {
4039 int ret, idx = 0;
4040 struct lttng_snapshot_output *list = NULL;
4041 struct lttng_ht_iter iter;
4042 struct snapshot_output *output;
4043
4044 assert(session);
4045 assert(outputs);
4046
4047 DBG("Cmd snapshot list outputs for session %s", session->name);
4048
4049 /*
4050 * Permission denied to create an output if the session is not
4051 * set in no output mode.
4052 */
4053 if (session->output_traces) {
4054 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4055 goto end;
4056 }
4057
4058 if (session->snapshot.nb_output == 0) {
4059 ret = 0;
4060 goto end;
4061 }
4062
4063 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
4064 if (!list) {
4065 ret = -LTTNG_ERR_NOMEM;
4066 goto end;
4067 }
4068
4069 /* Copy list from session to the new list object. */
4070 rcu_read_lock();
4071 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
4072 output, node.node) {
4073 assert(output->consumer);
4074 list[idx].id = output->id;
4075 list[idx].max_size = output->max_size;
4076 if (lttng_strncpy(list[idx].name, output->name,
4077 sizeof(list[idx].name))) {
4078 ret = -LTTNG_ERR_INVALID;
4079 goto error;
4080 }
4081 if (output->consumer->type == CONSUMER_DST_LOCAL) {
4082 if (lttng_strncpy(list[idx].ctrl_url,
4083 output->consumer->dst.session_root_path,
4084 sizeof(list[idx].ctrl_url))) {
4085 ret = -LTTNG_ERR_INVALID;
4086 goto error;
4087 }
4088 } else {
4089 /* Control URI. */
4090 ret = uri_to_str_url(&output->consumer->dst.net.control,
4091 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
4092 if (ret < 0) {
4093 ret = -LTTNG_ERR_NOMEM;
4094 goto error;
4095 }
4096
4097 /* Data URI. */
4098 ret = uri_to_str_url(&output->consumer->dst.net.data,
4099 list[idx].data_url, sizeof(list[idx].data_url));
4100 if (ret < 0) {
4101 ret = -LTTNG_ERR_NOMEM;
4102 goto error;
4103 }
4104 }
4105 idx++;
4106 }
4107
4108 *outputs = list;
4109 list = NULL;
4110 ret = session->snapshot.nb_output;
4111 error:
4112 rcu_read_unlock();
4113 free(list);
4114 end:
4115 return ret;
4116 }
4117
4118 /*
4119 * Check if we can regenerate the metadata for this session.
4120 * Only kernel, UST per-uid and non-live sessions are supported.
4121 *
4122 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
4123 */
4124 static
4125 int check_regenerate_metadata_support(struct ltt_session *session)
4126 {
4127 int ret;
4128
4129 assert(session);
4130
4131 if (session->live_timer != 0) {
4132 ret = LTTNG_ERR_LIVE_SESSION;
4133 goto end;
4134 }
4135 if (!session->active) {
4136 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4137 goto end;
4138 }
4139 if (session->ust_session) {
4140 switch (session->ust_session->buffer_type) {
4141 case LTTNG_BUFFER_PER_UID:
4142 break;
4143 case LTTNG_BUFFER_PER_PID:
4144 ret = LTTNG_ERR_PER_PID_SESSION;
4145 goto end;
4146 default:
4147 assert(0);
4148 ret = LTTNG_ERR_UNK;
4149 goto end;
4150 }
4151 }
4152 if (session->consumer->type == CONSUMER_DST_NET &&
4153 session->consumer->relay_minor_version < 8) {
4154 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
4155 goto end;
4156 }
4157 ret = 0;
4158
4159 end:
4160 return ret;
4161 }
4162
4163 static
4164 int clear_metadata_file(int fd)
4165 {
4166 int ret;
4167 off_t lseek_ret;
4168
4169 lseek_ret = lseek(fd, 0, SEEK_SET);
4170 if (lseek_ret < 0) {
4171 PERROR("lseek");
4172 ret = -1;
4173 goto end;
4174 }
4175
4176 ret = ftruncate(fd, 0);
4177 if (ret < 0) {
4178 PERROR("ftruncate");
4179 goto end;
4180 }
4181
4182 end:
4183 return ret;
4184 }
4185
4186 static
4187 int ust_regenerate_metadata(struct ltt_ust_session *usess)
4188 {
4189 int ret = 0;
4190 struct buffer_reg_uid *uid_reg = NULL;
4191 struct buffer_reg_session *session_reg = NULL;
4192
4193 rcu_read_lock();
4194 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
4195 struct ust_registry_session *registry;
4196 struct ust_registry_channel *chan;
4197 struct lttng_ht_iter iter_chan;
4198
4199 session_reg = uid_reg->registry;
4200 registry = session_reg->reg.ust;
4201
4202 pthread_mutex_lock(&registry->lock);
4203 registry->metadata_len_sent = 0;
4204 memset(registry->metadata, 0, registry->metadata_alloc_len);
4205 registry->metadata_len = 0;
4206 registry->metadata_version++;
4207 if (registry->metadata_fd > 0) {
4208 /* Clear the metadata file's content. */
4209 ret = clear_metadata_file(registry->metadata_fd);
4210 if (ret) {
4211 pthread_mutex_unlock(&registry->lock);
4212 goto end;
4213 }
4214 }
4215
4216 ret = ust_metadata_session_statedump(registry, NULL,
4217 registry->major, registry->minor);
4218 if (ret) {
4219 pthread_mutex_unlock(&registry->lock);
4220 ERR("Failed to generate session metadata (err = %d)",
4221 ret);
4222 goto end;
4223 }
4224 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
4225 chan, node.node) {
4226 struct ust_registry_event *event;
4227 struct lttng_ht_iter iter_event;
4228
4229 ret = ust_metadata_channel_statedump(registry, chan);
4230 if (ret) {
4231 pthread_mutex_unlock(&registry->lock);
4232 ERR("Failed to generate channel metadata "
4233 "(err = %d)", ret);
4234 goto end;
4235 }
4236 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
4237 event, node.node) {
4238 ret = ust_metadata_event_statedump(registry,
4239 chan, event);
4240 if (ret) {
4241 pthread_mutex_unlock(&registry->lock);
4242 ERR("Failed to generate event metadata "
4243 "(err = %d)", ret);
4244 goto end;
4245 }
4246 }
4247 }
4248 pthread_mutex_unlock(&registry->lock);
4249 }
4250
4251 end:
4252 rcu_read_unlock();
4253 return ret;
4254 }
4255
4256 /*
4257 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
4258 *
4259 * Ask the consumer to truncate the existing metadata file(s) and
4260 * then regenerate the metadata. Live and per-pid sessions are not
4261 * supported and return an error.
4262 *
4263 * Return 0 on success or else a LTTNG_ERR code.
4264 */
4265 int cmd_regenerate_metadata(struct ltt_session *session)
4266 {
4267 int ret;
4268
4269 assert(session);
4270
4271 ret = check_regenerate_metadata_support(session);
4272 if (ret) {
4273 goto end;
4274 }
4275
4276 if (session->kernel_session) {
4277 ret = kernctl_session_regenerate_metadata(
4278 session->kernel_session->fd);
4279 if (ret < 0) {
4280 ERR("Failed to regenerate the kernel metadata");
4281 goto end;
4282 }
4283 }
4284
4285 if (session->ust_session) {
4286 ret = ust_regenerate_metadata(session->ust_session);
4287 if (ret < 0) {
4288 ERR("Failed to regenerate the UST metadata");
4289 goto end;
4290 }
4291 }
4292 DBG("Cmd metadata regenerate for session %s", session->name);
4293 ret = LTTNG_OK;
4294
4295 end:
4296 return ret;
4297 }
4298
4299 /*
4300 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
4301 *
4302 * Ask the tracer to regenerate a new statedump.
4303 *
4304 * Return 0 on success or else a LTTNG_ERR code.
4305 */
4306 int cmd_regenerate_statedump(struct ltt_session *session)
4307 {
4308 int ret;
4309
4310 assert(session);
4311
4312 if (!session->active) {
4313 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4314 goto end;
4315 }
4316
4317 if (session->kernel_session) {
4318 ret = kernctl_session_regenerate_statedump(
4319 session->kernel_session->fd);
4320 /*
4321 * Currently, the statedump in kernel can only fail if out
4322 * of memory.
4323 */
4324 if (ret < 0) {
4325 if (ret == -ENOMEM) {
4326 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
4327 } else {
4328 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4329 }
4330 ERR("Failed to regenerate the kernel statedump");
4331 goto end;
4332 }
4333 }
4334
4335 if (session->ust_session) {
4336 ret = ust_app_regenerate_statedump_all(session->ust_session);
4337 /*
4338 * Currently, the statedump in UST always returns 0.
4339 */
4340 if (ret < 0) {
4341 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4342 ERR("Failed to regenerate the UST statedump");
4343 goto end;
4344 }
4345 }
4346 DBG("Cmd regenerate statedump for session %s", session->name);
4347 ret = LTTNG_OK;
4348
4349 end:
4350 return ret;
4351 }
4352
4353 /* TODO: is this the best place to perform this? (code wise) */
4354 /*
4355 * Set sock to -1 if reception of more information is not necessary e.g on
4356 * unregister. TODO find a better way.
4357 *
4358 * On success LTTNG_OK. On error, returns lttng_error code.
4359 * */
4360 static enum lttng_error_code prepare_trigger_object(struct lttng_trigger *trigger, int sock)
4361 {
4362 enum lttng_error_code ret;
4363 /* Internal object of the trigger might have to "generate" and
4364 * "populate" internal field e.g filter bytecode
4365 */
4366 struct lttng_condition *condition = NULL;
4367
4368 condition = lttng_trigger_get_condition(trigger);
4369 if (!condition) {
4370 ret = LTTNG_ERR_INVALID_TRIGGER;
4371 goto end;
4372 }
4373
4374 switch (lttng_condition_get_type(condition)) {
4375 case LTTNG_CONDITION_TYPE_EVENT_RULE_HIT:
4376 {
4377 struct lttng_event_rule *event_rule;
4378 const struct lttng_credentials *credential = lttng_trigger_get_credentials(trigger);
4379 lttng_condition_event_rule_get_rule_no_const(
4380 condition, &event_rule);
4381 ret = lttng_event_rule_populate(event_rule, credential->uid, credential->gid);
4382 if (ret != LTTNG_OK) {
4383 goto end;
4384 }
4385
4386 switch (lttng_event_rule_get_type(event_rule)) {
4387 case LTTNG_EVENT_RULE_TYPE_UPROBE:
4388 {
4389 int fd;
4390 struct lttng_userspace_probe_location *location = lttng_event_rule_uprobe_get_location_no_const(event_rule);
4391
4392 if (sock < 0) {
4393 /* Nothing to receive */
4394 break;
4395 }
4396 /*
4397 * Receive the file descriptor to the target binary from
4398 * the client.
4399 */
4400 DBG("Receiving userspace probe target FD from client ...");
4401 ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1);
4402 if (ret <= 0) {
4403 DBG("Nothing recv() from client userspace probe fd... continuing");
4404 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
4405 goto end;
4406 }
4407
4408 /*
4409 * Set the file descriptor received from the client
4410 * through the unix socket in the probe location.
4411 */
4412 ret = lttng_userspace_probe_location_set_binary_fd(
4413 location, fd);
4414 if (ret) {
4415 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
4416 goto end;
4417 }
4418
4419 break;
4420 }
4421 default:
4422 /* Nothing to do */
4423 break;
4424 }
4425
4426 /* Generate the capture bytecode set */
4427 ret = lttng_condition_event_rule_generate_capture_descriptor_bytecode_set(
4428 condition, &trigger->capture_bytecode_set);
4429 break;
4430 }
4431 default:
4432 {
4433 ret = LTTNG_OK;
4434 break;
4435 }
4436 }
4437
4438
4439 end:
4440 return ret;
4441 }
4442
4443 /* Caller must call lttng_destroy_trigger on the returned trigger object */
4444 int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
4445 struct notification_thread_handle *notification_thread,
4446 struct lttng_trigger **return_trigger)
4447 {
4448 int ret;
4449 size_t trigger_len;
4450 ssize_t sock_recv_len;
4451 struct lttng_trigger *trigger = NULL;
4452 struct lttng_buffer_view view;
4453 struct lttng_dynamic_buffer trigger_buffer;
4454
4455 lttng_dynamic_buffer_init(&trigger_buffer);
4456 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4457 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4458 if (ret) {
4459 ret = LTTNG_ERR_NOMEM;
4460 goto end;
4461 }
4462
4463 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4464 trigger_len);
4465 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4466 ERR("Failed to receive \"register trigger\" command payload");
4467 /* TODO: should this be a new error enum ? */
4468 ret = LTTNG_ERR_INVALID_TRIGGER;
4469 goto end;
4470 }
4471
4472 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4473 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4474 trigger_len) {
4475 ERR("Invalid trigger payload received in \"register trigger\" command");
4476 ret = LTTNG_ERR_INVALID_TRIGGER;
4477 goto end;
4478 }
4479
4480 /*
4481 * Since we return the trigger object, take a reference to it
4482 * Caller is responsible for calling lttng_destroy_trigger on it.
4483 * This thread does not OWN the trigger.
4484 */
4485 lttng_trigger_get(trigger);
4486
4487 /* Set the trigger credential */
4488 lttng_trigger_set_credentials(trigger, cmd_ctx->creds.uid, cmd_ctx->creds.gid);
4489
4490 /* Prepare internal trigger object if needed on reception.
4491 * Handles also special treatment for certain internal object of the
4492 * trigger (e.g uprobe event rule binary fd.
4493 */
4494 ret = prepare_trigger_object(trigger, sock);
4495 if (ret != LTTNG_OK) {
4496 goto end;
4497 }
4498
4499 /* Inform the notification thread */
4500 ret = notification_thread_command_register_trigger(notification_thread,
4501 trigger);
4502 if (ret != LTTNG_OK) {
4503 goto end;
4504 }
4505
4506 /* Synchronize tracers, only if needed */
4507 /* TODO: maybe extract somewhere else */
4508 {
4509 struct lttng_condition *condition = NULL;
4510 condition = lttng_trigger_get_condition(trigger);
4511 if (!condition) {
4512 ret = LTTNG_ERR_INVALID_TRIGGER;
4513 goto end;
4514 }
4515
4516 if (lttng_condition_get_type(condition) == LTTNG_CONDITION_TYPE_EVENT_RULE_HIT) {
4517 const struct lttng_event_rule *rule = NULL;
4518 (void) lttng_condition_event_rule_get_rule(condition, &rule);
4519 if (!rule) {
4520 ret = LTTNG_ERR_INVALID_TRIGGER;
4521 goto end;
4522 }
4523 if (lttng_event_rule_get_domain_type(rule) == LTTNG_DOMAIN_KERNEL) {
4524 /* TODO: get the token value from the
4525 * notification thread and only perform an
4526 * enable and a disable.... This is NOT
4527 * OPTIMIZED AT ALL
4528 */
4529 kernel_update_tokens();
4530 } else {
4531 /* TODO: get the token value from the
4532 * notification thread and only perform an
4533 * enable and a disable.... This is NOT
4534 * OPTIMIZED AT ALL
4535 */
4536 ust_app_global_update_all_tokens();
4537 /* Agent handling */
4538 if (lttng_event_rule_is_agent(rule)) {
4539 struct agent *agt;
4540 const char *pattern;
4541 enum lttng_domain_type domain_type;
4542 domain_type = lttng_event_rule_get_domain_type(
4543 rule);
4544 (void) lttng_event_rule_tracepoint_get_pattern(
4545 rule, &pattern);
4546 agt = trigger_find_agent(domain_type);
4547 if (!agt) {
4548 agt = agent_create(domain_type);
4549 if (!agt) {
4550 ret = LTTNG_ERR_NOMEM;
4551 goto end;
4552 }
4553 agent_add(agt, trigger_agents_ht_by_domain);
4554 }
4555
4556 ret = trigger_agent_enable(
4557 trigger, agt);
4558 if (ret != LTTNG_OK) {
4559 goto end;
4560 }
4561 }
4562 }
4563 }
4564 }
4565
4566 /* Return an image of the updated object to the client */
4567 *return_trigger = trigger;
4568 /* Ownership of trigger was transferred to caller. */
4569 trigger = NULL;
4570 end:
4571 lttng_trigger_destroy(trigger);
4572 lttng_dynamic_buffer_reset(&trigger_buffer);
4573 return ret;
4574 }
4575
4576 int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
4577 struct notification_thread_handle *notification_thread)
4578 {
4579 int ret;
4580 size_t trigger_len;
4581 ssize_t sock_recv_len;
4582 struct lttng_trigger *trigger = NULL;
4583 struct lttng_buffer_view view;
4584 struct lttng_dynamic_buffer trigger_buffer;
4585
4586 lttng_dynamic_buffer_init(&trigger_buffer);
4587 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4588 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4589 if (ret) {
4590 ret = LTTNG_ERR_NOMEM;
4591 goto end;
4592 }
4593
4594 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4595 trigger_len);
4596 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4597 ERR("Failed to receive \"unregister trigger\" command payload");
4598 /* TODO: should this be a new error enum ? */
4599 ret = LTTNG_ERR_INVALID_TRIGGER;
4600 goto end;
4601 }
4602
4603 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4604 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4605 trigger_len) {
4606 ERR("Invalid trigger payload received in \"unregister trigger\" command");
4607 ret = LTTNG_ERR_INVALID_TRIGGER;
4608 goto end;
4609 }
4610
4611 lttng_trigger_set_credentials(trigger, cmd_ctx->creds.uid, cmd_ctx->creds.gid);
4612
4613 ret = prepare_trigger_object(trigger, -1);
4614 if (ret != LTTNG_OK) {
4615 goto end;
4616 }
4617
4618 ret = notification_thread_command_unregister_trigger(notification_thread,
4619 trigger);
4620
4621 /* Synchronize tracers, only if needed */
4622 /* TODO: maybe extract somewhere else */
4623 {
4624 struct lttng_condition *condition = NULL;
4625 condition = lttng_trigger_get_condition(trigger);
4626 if (!condition) {
4627 ret = LTTNG_ERR_INVALID_TRIGGER;
4628 goto end;
4629 }
4630
4631 if (lttng_condition_get_type(condition) == LTTNG_CONDITION_TYPE_EVENT_RULE_HIT) {
4632 const struct lttng_event_rule *rule = NULL;
4633 (void) lttng_condition_event_rule_get_rule(condition, &rule);
4634 if (!rule) {
4635 ret = LTTNG_ERR_INVALID_TRIGGER;
4636 goto end;
4637 }
4638 if (lttng_event_rule_get_domain_type(rule) == LTTNG_DOMAIN_KERNEL) {
4639 /* TODO: get the token value from the
4640 * notification thread and only perform an
4641 * enable and a disable.... This is NOT
4642 * OPTIMIZED AT ALL
4643 */
4644 kernel_update_tokens();
4645 } else {
4646 /* TODO: get the token value from the
4647 * notification thread and only perform an
4648 * enable and a disable.... This is NOT
4649 * OPTIMIZED AT ALL
4650 */
4651 ust_app_global_update_all_tokens();
4652 if (lttng_event_rule_is_agent(rule)) {
4653 struct agent *agt;
4654 const char *pattern;
4655 enum lttng_domain_type domain_type;
4656
4657 domain_type = lttng_event_rule_get_domain_type(
4658 rule);
4659 (void) lttng_event_rule_tracepoint_get_pattern(
4660 rule, &pattern);
4661
4662 agt = trigger_find_agent(domain_type);
4663 if (!agt) {
4664 ret = LTTNG_ERR_UST_EVENT_NOT_FOUND;
4665 goto end;
4666 }
4667 ret = trigger_agent_disable(
4668 trigger, agt);
4669 if (ret != LTTNG_OK) {
4670 goto end;
4671 }
4672 }
4673 }
4674 }
4675 }
4676
4677 end:
4678 lttng_trigger_destroy(trigger);
4679 lttng_dynamic_buffer_reset(&trigger_buffer);
4680 return ret;
4681 }
4682
4683 int cmd_list_triggers(struct command_ctx *cmd_ctx, int sock,
4684 struct notification_thread_handle *notification_thread,
4685 struct lttng_triggers **return_triggers)
4686 {
4687 int ret = 0;
4688 enum lttng_error_code ret_code;
4689 struct lttng_triggers *triggers = NULL;
4690
4691 /* Get list of token trigger from the notification thread here */
4692 ret_code = notification_thread_command_list_triggers(notification_thread_handle, cmd_ctx->creds.uid, cmd_ctx->creds.gid, &triggers);
4693 if (ret_code != LTTNG_OK) {
4694 ret = ret_code;
4695 goto end;
4696 }
4697
4698 /* Return a "view" of the current triggers */
4699 *return_triggers = triggers;
4700 triggers = NULL;
4701 ret = LTTNG_OK;
4702 end:
4703 lttng_triggers_destroy(triggers);
4704 return ret;
4705 }
4706 /*
4707 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4708 * snapshot output is *not* set with a remote destination.
4709 *
4710 * Return LTTNG_OK on success or a LTTNG_ERR code.
4711 */
4712 static enum lttng_error_code set_relayd_for_snapshot(
4713 struct consumer_output *output,
4714 const struct ltt_session *session)
4715 {
4716 enum lttng_error_code status = LTTNG_OK;
4717 struct lttng_ht_iter iter;
4718 struct consumer_socket *socket;
4719 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
4720 const char *base_path;
4721
4722 assert(output);
4723 assert(session);
4724
4725 DBG2("Set relayd object from snapshot output");
4726
4727 if (session->current_trace_chunk) {
4728 enum lttng_trace_chunk_status chunk_status =
4729 lttng_trace_chunk_get_id(
4730 session->current_trace_chunk,
4731 &current_chunk_id.value);
4732
4733 if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK) {
4734 current_chunk_id.is_set = true;
4735 } else {
4736 ERR("Failed to get current trace chunk id");
4737 status = LTTNG_ERR_UNK;
4738 goto error;
4739 }
4740 }
4741
4742 /* Ignore if snapshot consumer output is not network. */
4743 if (output->type != CONSUMER_DST_NET) {
4744 goto error;
4745 }
4746
4747 /*
4748 * The snapshot record URI base path overrides the session
4749 * base path.
4750 */
4751 if (output->dst.net.control.subdir[0] != '\0') {
4752 base_path = output->dst.net.control.subdir;
4753 } else {
4754 base_path = session->base_path;
4755 }
4756
4757 /*
4758 * For each consumer socket, create and send the relayd object of the
4759 * snapshot output.
4760 */
4761 rcu_read_lock();
4762 cds_lfht_for_each_entry(output->socks->ht, &iter.iter,
4763 socket, node.node) {
4764 pthread_mutex_lock(socket->lock);
4765 status = send_consumer_relayd_sockets(0, session->id,
4766 output, socket,
4767 session->name, session->hostname,
4768 base_path,
4769 session->live_timer,
4770 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
4771 session->creation_time,
4772 session->name_contains_creation_time);
4773 pthread_mutex_unlock(socket->lock);
4774 if (status != LTTNG_OK) {
4775 rcu_read_unlock();
4776 goto error;
4777 }
4778 }
4779 rcu_read_unlock();
4780
4781 error:
4782 return status;
4783 }
4784
4785 /*
4786 * Record a kernel snapshot.
4787 *
4788 * Return LTTNG_OK on success or a LTTNG_ERR code.
4789 */
4790 static enum lttng_error_code record_kernel_snapshot(
4791 struct ltt_kernel_session *ksess,
4792 const struct consumer_output *output,
4793 const struct ltt_session *session,
4794 int wait, uint64_t nb_packets_per_stream)
4795 {
4796 enum lttng_error_code status;
4797
4798 assert(ksess);
4799 assert(output);
4800 assert(session);
4801
4802 status = kernel_snapshot_record(
4803 ksess, output, wait, nb_packets_per_stream);
4804 return status;
4805 }
4806
4807 /*
4808 * Record a UST snapshot.
4809 *
4810 * Returns LTTNG_OK on success or a LTTNG_ERR error code.
4811 */
4812 static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
4813 const struct consumer_output *output,
4814 const struct ltt_session *session,
4815 int wait, uint64_t nb_packets_per_stream)
4816 {
4817 enum lttng_error_code status;
4818
4819 assert(usess);
4820 assert(output);
4821 assert(session);
4822
4823 status = ust_app_snapshot_record(
4824 usess, output, wait, nb_packets_per_stream);
4825 return status;
4826 }
4827
4828 static
4829 uint64_t get_session_size_one_more_packet_per_stream(
4830 const struct ltt_session *session, uint64_t cur_nr_packets)
4831 {
4832 uint64_t tot_size = 0;
4833
4834 if (session->kernel_session) {
4835 struct ltt_kernel_channel *chan;
4836 const struct ltt_kernel_session *ksess =
4837 session->kernel_session;
4838
4839 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
4840 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
4841 /*
4842 * Don't take channel into account if we
4843 * already grab all its packets.
4844 */
4845 continue;
4846 }
4847 tot_size += chan->channel->attr.subbuf_size
4848 * chan->stream_count;
4849 }
4850 }
4851
4852 if (session->ust_session) {
4853 const struct ltt_ust_session *usess = session->ust_session;
4854
4855 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
4856 cur_nr_packets);
4857 }
4858
4859 return tot_size;
4860 }
4861
4862 /*
4863 * Calculate the number of packets we can grab from each stream that
4864 * fits within the overall snapshot max size.
4865 *
4866 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
4867 * the number of packets per stream.
4868 *
4869 * TODO: this approach is not perfect: we consider the worse case
4870 * (packet filling the sub-buffers) as an upper bound, but we could do
4871 * better if we do this calculation while we actually grab the packet
4872 * content: we would know how much padding we don't actually store into
4873 * the file.
4874 *
4875 * This algorithm is currently bounded by the number of packets per
4876 * stream.
4877 *
4878 * Since we call this algorithm before actually grabbing the data, it's
4879 * an approximation: for instance, applications could appear/disappear
4880 * in between this call and actually grabbing data.
4881 */
4882 static
4883 int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
4884 uint64_t max_size)
4885 {
4886 int64_t size_left;
4887 uint64_t cur_nb_packets = 0;
4888
4889 if (!max_size) {
4890 return 0; /* Infinite */
4891 }
4892
4893 size_left = max_size;
4894 for (;;) {
4895 uint64_t one_more_packet_tot_size;
4896
4897 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(
4898 session, cur_nb_packets);
4899 if (!one_more_packet_tot_size) {
4900 /* We are already grabbing all packets. */
4901 break;
4902 }
4903 size_left -= one_more_packet_tot_size;
4904 if (size_left < 0) {
4905 break;
4906 }
4907 cur_nb_packets++;
4908 }
4909 if (!cur_nb_packets && size_left != max_size) {
4910 /* Not enough room to grab one packet of each stream, error. */
4911 return -1;
4912 }
4913 return cur_nb_packets;
4914 }
4915
4916 static
4917 enum lttng_error_code snapshot_record(struct ltt_session *session,
4918 const struct snapshot_output *snapshot_output, int wait)
4919 {
4920 int64_t nb_packets_per_stream;
4921 char snapshot_chunk_name[LTTNG_NAME_MAX];
4922 int ret;
4923 enum lttng_error_code ret_code = LTTNG_OK;
4924 struct lttng_trace_chunk *snapshot_trace_chunk;
4925 struct consumer_output *original_ust_consumer_output = NULL;
4926 struct consumer_output *original_kernel_consumer_output = NULL;
4927 struct consumer_output *snapshot_ust_consumer_output = NULL;
4928 struct consumer_output *snapshot_kernel_consumer_output = NULL;
4929
4930 ret = snprintf(snapshot_chunk_name, sizeof(snapshot_chunk_name),
4931 "%s-%s-%" PRIu64,
4932 snapshot_output->name,
4933 snapshot_output->datetime,
4934 snapshot_output->nb_snapshot);
4935 if (ret < 0 || ret >= sizeof(snapshot_chunk_name)) {
4936 ERR("Failed to format snapshot name");
4937 ret_code = LTTNG_ERR_INVALID;
4938 goto error;
4939 }
4940 DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
4941 snapshot_output->name, session->name,
4942 snapshot_chunk_name);
4943 if (!session->kernel_session && !session->ust_session) {
4944 ERR("Failed to record snapshot as no channels exist");
4945 ret_code = LTTNG_ERR_NO_CHANNEL;
4946 goto error;
4947 }
4948
4949 if (session->kernel_session) {
4950 original_kernel_consumer_output =
4951 session->kernel_session->consumer;
4952 snapshot_kernel_consumer_output =
4953 consumer_copy_output(snapshot_output->consumer);
4954 strcpy(snapshot_kernel_consumer_output->chunk_path,
4955 snapshot_chunk_name);
4956 ret = consumer_copy_sockets(snapshot_kernel_consumer_output,
4957 original_kernel_consumer_output);
4958 if (ret < 0) {
4959 ERR("Failed to copy consumer sockets from snapshot output configuration");
4960 ret_code = LTTNG_ERR_NOMEM;
4961 goto error;
4962 }
4963 ret_code = set_relayd_for_snapshot(
4964 snapshot_kernel_consumer_output, session);
4965 if (ret_code != LTTNG_OK) {
4966 ERR("Failed to setup relay daemon for kernel tracer snapshot");
4967 goto error;
4968 }
4969 session->kernel_session->consumer =
4970 snapshot_kernel_consumer_output;
4971 }
4972 if (session->ust_session) {
4973 original_ust_consumer_output = session->ust_session->consumer;
4974 snapshot_ust_consumer_output =
4975 consumer_copy_output(snapshot_output->consumer);
4976 strcpy(snapshot_ust_consumer_output->chunk_path,
4977 snapshot_chunk_name);
4978 ret = consumer_copy_sockets(snapshot_ust_consumer_output,
4979 original_ust_consumer_output);
4980 if (ret < 0) {
4981 ERR("Failed to copy consumer sockets from snapshot output configuration");
4982 ret_code = LTTNG_ERR_NOMEM;
4983 goto error;
4984 }
4985 ret_code = set_relayd_for_snapshot(
4986 snapshot_ust_consumer_output, session);
4987 if (ret_code != LTTNG_OK) {
4988 ERR("Failed to setup relay daemon for userspace tracer snapshot");
4989 goto error;
4990 }
4991 session->ust_session->consumer =
4992 snapshot_ust_consumer_output;
4993 }
4994
4995 snapshot_trace_chunk = session_create_new_trace_chunk(session,
4996 snapshot_kernel_consumer_output ?:
4997 snapshot_ust_consumer_output,
4998 consumer_output_get_base_path(
4999 snapshot_output->consumer),
5000 snapshot_chunk_name);
5001 if (!snapshot_trace_chunk) {
5002 ERR("Failed to create temporary trace chunk to record a snapshot of session \"%s\"",
5003 session->name);
5004 ret_code = LTTNG_ERR_CREATE_DIR_FAIL;
5005 goto error;
5006 }
5007 assert(!session->current_trace_chunk);
5008 ret = session_set_trace_chunk(session, snapshot_trace_chunk, NULL);
5009 lttng_trace_chunk_put(snapshot_trace_chunk);
5010 snapshot_trace_chunk = NULL;
5011 if (ret) {
5012 ERR("Failed to set temporary trace chunk to record a snapshot of session \"%s\"",
5013 session->name);
5014 ret_code = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
5015 goto error;
5016 }
5017
5018 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
5019 snapshot_output->max_size);
5020 if (nb_packets_per_stream < 0) {
5021 ret_code = LTTNG_ERR_MAX_SIZE_INVALID;
5022 goto error_close_trace_chunk;
5023 }
5024
5025 if (session->kernel_session) {
5026 ret_code = record_kernel_snapshot(session->kernel_session,
5027 snapshot_kernel_consumer_output, session,
5028 wait, nb_packets_per_stream);
5029 if (ret_code != LTTNG_OK) {
5030 goto error_close_trace_chunk;
5031 }
5032 }
5033
5034 if (session->ust_session) {
5035 ret_code = record_ust_snapshot(session->ust_session,
5036 snapshot_ust_consumer_output, session,
5037 wait, nb_packets_per_stream);
5038 if (ret_code != LTTNG_OK) {
5039 goto error_close_trace_chunk;
5040 }
5041 }
5042
5043 error_close_trace_chunk:
5044 if (session_set_trace_chunk(session, NULL, &snapshot_trace_chunk)) {
5045 ERR("Failed to release the current trace chunk of session \"%s\"",
5046 session->name);
5047 ret_code = LTTNG_ERR_UNK;
5048 }
5049
5050 if (session_close_trace_chunk(session, snapshot_trace_chunk,
5051 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION, NULL)) {
5052 /*
5053 * Don't goto end; make sure the chunk is closed for the session
5054 * to allow future snapshots.
5055 */
5056 ERR("Failed to close snapshot trace chunk of session \"%s\"",
5057 session->name);
5058 ret_code = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5059 }
5060 error:
5061 if (original_ust_consumer_output) {
5062 session->ust_session->consumer = original_ust_consumer_output;
5063 }
5064 if (original_kernel_consumer_output) {
5065 session->kernel_session->consumer =
5066 original_kernel_consumer_output;
5067 }
5068 consumer_output_put(snapshot_ust_consumer_output);
5069 consumer_output_put(snapshot_kernel_consumer_output);
5070 return ret_code;
5071 }
5072
5073 /*
5074 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
5075 *
5076 * The wait parameter is ignored so this call always wait for the snapshot to
5077 * complete before returning.
5078 *
5079 * Return LTTNG_OK on success or else a LTTNG_ERR code.
5080 */
5081 int cmd_snapshot_record(struct ltt_session *session,
5082 const struct lttng_snapshot_output *output, int wait)
5083 {
5084 enum lttng_error_code cmd_ret = LTTNG_OK;
5085 int ret;
5086 unsigned int snapshot_success = 0;
5087 char datetime[16];
5088 struct snapshot_output *tmp_output = NULL;
5089
5090 assert(session);
5091 assert(output);
5092
5093 DBG("Cmd snapshot record for session %s", session->name);
5094
5095 /* Get the datetime for the snapshot output directory. */
5096 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
5097 sizeof(datetime));
5098 if (!ret) {
5099 cmd_ret = LTTNG_ERR_INVALID;
5100 goto error;
5101 }
5102
5103 /*
5104 * Permission denied to create an output if the session is not
5105 * set in no output mode.
5106 */
5107 if (session->output_traces) {
5108 cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
5109 goto error;
5110 }
5111
5112 /* The session needs to be started at least once. */
5113 if (!session->has_been_started) {
5114 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
5115 goto error;
5116 }
5117
5118 /* Use temporary output for the session. */
5119 if (*output->ctrl_url != '\0') {
5120 tmp_output = snapshot_output_alloc();
5121 if (!tmp_output) {
5122 cmd_ret = LTTNG_ERR_NOMEM;
5123 goto error;
5124 }
5125
5126 ret = snapshot_output_init(session, output->max_size,
5127 output->name,
5128 output->ctrl_url, output->data_url,
5129 session->consumer,
5130 tmp_output, NULL);
5131 if (ret < 0) {
5132 if (ret == -ENOMEM) {
5133 cmd_ret = LTTNG_ERR_NOMEM;
5134 } else {
5135 cmd_ret = LTTNG_ERR_INVALID;
5136 }
5137 goto error;
5138 }
5139 /* Use the global session count for the temporary snapshot. */
5140 tmp_output->nb_snapshot = session->snapshot.nb_snapshot;
5141
5142 /* Use the global datetime */
5143 memcpy(tmp_output->datetime, datetime, sizeof(datetime));
5144 cmd_ret = snapshot_record(session, tmp_output, wait);
5145 if (cmd_ret != LTTNG_OK) {
5146 goto error;
5147 }
5148 snapshot_success = 1;
5149 } else {
5150 struct snapshot_output *sout;
5151 struct lttng_ht_iter iter;
5152
5153 rcu_read_lock();
5154 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
5155 &iter.iter, sout, node.node) {
5156 struct snapshot_output output_copy;
5157
5158 /*
5159 * Make a local copy of the output and override output
5160 * parameters with those provided as part of the
5161 * command.
5162 */
5163 memcpy(&output_copy, sout, sizeof(output_copy));
5164
5165 if (output->max_size != (uint64_t) -1ULL) {
5166 output_copy.max_size = output->max_size;
5167 }
5168
5169 output_copy.nb_snapshot = session->snapshot.nb_snapshot;
5170 memcpy(output_copy.datetime, datetime,
5171 sizeof(datetime));
5172
5173 /* Use temporary name. */
5174 if (*output->name != '\0') {
5175 if (lttng_strncpy(output_copy.name,
5176 output->name,
5177 sizeof(output_copy.name))) {
5178 cmd_ret = LTTNG_ERR_INVALID;
5179 rcu_read_unlock();
5180 goto error;
5181 }
5182 }
5183
5184 cmd_ret = snapshot_record(session, &output_copy, wait);
5185 if (cmd_ret != LTTNG_OK) {
5186 rcu_read_unlock();
5187 goto error;
5188 }
5189 snapshot_success = 1;
5190 }
5191 rcu_read_unlock();
5192 }
5193
5194 if (snapshot_success) {
5195 session->snapshot.nb_snapshot++;
5196 } else {
5197 cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
5198 }
5199
5200 error:
5201 if (tmp_output) {
5202 snapshot_output_destroy(tmp_output);
5203 }
5204 return cmd_ret;
5205 }
5206
5207 /*
5208 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
5209 */
5210 int cmd_set_session_shm_path(struct ltt_session *session,
5211 const char *shm_path)
5212 {
5213 /* Safety net */
5214 assert(session);
5215
5216 /*
5217 * Can only set shm path before session is started.
5218 */
5219 if (session->has_been_started) {
5220 return LTTNG_ERR_SESSION_STARTED;
5221 }
5222
5223 strncpy(session->shm_path, shm_path,
5224 sizeof(session->shm_path));
5225 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
5226
5227 return 0;
5228 }
5229
5230 /*
5231 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
5232 *
5233 * Ask the consumer to rotate the session output directory.
5234 * The session lock must be held.
5235 *
5236 * Returns LTTNG_OK on success or else a negative LTTng error code.
5237 */
5238 int cmd_rotate_session(struct ltt_session *session,
5239 struct lttng_rotate_session_return *rotate_return,
5240 bool quiet_rotation,
5241 enum lttng_trace_chunk_command_type command)
5242 {
5243 int ret;
5244 uint64_t ongoing_rotation_chunk_id;
5245 enum lttng_error_code cmd_ret = LTTNG_OK;
5246 struct lttng_trace_chunk *chunk_being_archived = NULL;
5247 struct lttng_trace_chunk *new_trace_chunk = NULL;
5248 enum lttng_trace_chunk_status chunk_status;
5249 bool failed_to_rotate = false;
5250 enum lttng_error_code rotation_fail_code = LTTNG_OK;
5251
5252 assert(session);
5253
5254 if (!session->has_been_started) {
5255 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
5256 goto end;
5257 }
5258
5259 /*
5260 * Explicit rotation is not supported for live sessions.
5261 * However, live sessions can perform a quiet rotation on
5262 * destroy.
5263 * Rotation is not supported for snapshot traces (no output).
5264 */
5265 if ((!quiet_rotation && session->live_timer) ||
5266 !session->output_traces) {
5267 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5268 goto end;
5269 }
5270
5271 /* Unsupported feature in lttng-relayd before 2.11. */
5272 if (!quiet_rotation && session->consumer->type == CONSUMER_DST_NET &&
5273 (session->consumer->relay_major_version == 2 &&
5274 session->consumer->relay_minor_version < 11)) {
5275 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
5276 goto end;
5277 }
5278
5279 /* Unsupported feature in lttng-modules before 2.8 (lack of sequence number). */
5280 if (session->kernel_session && !kernel_supports_ring_buffer_packet_sequence_number()) {
5281 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL;
5282 goto end;
5283 }
5284
5285 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
5286 DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
5287 session->name);
5288 cmd_ret = LTTNG_ERR_ROTATION_PENDING;
5289 goto end;
5290 }
5291
5292 /*
5293 * After a stop, we only allow one rotation to occur, the other ones are
5294 * useless until a new start.
5295 */
5296 if (session->rotated_after_last_stop) {
5297 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
5298 session->name);
5299 cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
5300 goto end;
5301 }
5302
5303 /*
5304 * After a stop followed by a clear, disallow following rotations a they would
5305 * generate empty chunks.
5306 */
5307 if (session->cleared_after_last_stop) {
5308 DBG("Session \"%s\" was already cleared after stop, refusing rotation",
5309 session->name);
5310 cmd_ret = LTTNG_ERR_ROTATION_AFTER_STOP_CLEAR;
5311 goto end;
5312 }
5313
5314 if (session->active) {
5315 new_trace_chunk = session_create_new_trace_chunk(session, NULL,
5316 NULL, NULL);
5317 if (!new_trace_chunk) {
5318 cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
5319 goto error;
5320 }
5321 }
5322
5323 /*
5324 * The current trace chunk becomes the chunk being archived.
5325 *
5326 * After this point, "chunk_being_archived" must absolutely
5327 * be closed on the consumer(s), otherwise it will never be
5328 * cleaned-up, which will result in a leak.
5329 */
5330 ret = session_set_trace_chunk(session, new_trace_chunk,
5331 &chunk_being_archived);
5332 if (ret) {
5333 cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
5334 goto error;
5335 }
5336
5337 if (session->kernel_session) {
5338 cmd_ret = kernel_rotate_session(session);
5339 if (cmd_ret != LTTNG_OK) {
5340 failed_to_rotate = true;
5341 rotation_fail_code = cmd_ret;
5342 }
5343 }
5344 if (session->ust_session) {
5345 cmd_ret = ust_app_rotate_session(session);
5346 if (cmd_ret != LTTNG_OK) {
5347 failed_to_rotate = true;
5348 rotation_fail_code = cmd_ret;
5349 }
5350 }
5351
5352 if (!session->active) {
5353 session->rotated_after_last_stop = true;
5354 }
5355
5356 if (!chunk_being_archived) {
5357 DBG("Rotating session \"%s\" from a \"NULL\" trace chunk to a new trace chunk, skipping completion check",
5358 session->name);
5359 if (failed_to_rotate) {
5360 cmd_ret = rotation_fail_code;
5361 goto error;
5362 }
5363 cmd_ret = LTTNG_OK;
5364 goto end;
5365 }
5366
5367 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
5368 chunk_status = lttng_trace_chunk_get_id(chunk_being_archived,
5369 &ongoing_rotation_chunk_id);
5370 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5371
5372 ret = session_close_trace_chunk(session, chunk_being_archived,
5373 command, session->last_chunk_path);
5374 if (ret) {
5375 cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5376 goto error;
5377 }
5378
5379 if (failed_to_rotate) {
5380 cmd_ret = rotation_fail_code;
5381 goto error;
5382 }
5383
5384 session->quiet_rotation = quiet_rotation;
5385 ret = timer_session_rotation_pending_check_start(session,
5386 DEFAULT_ROTATE_PENDING_TIMER);
5387 if (ret) {
5388 cmd_ret = LTTNG_ERR_UNK;
5389 goto error;
5390 }
5391
5392 if (rotate_return) {
5393 rotate_return->rotation_id = ongoing_rotation_chunk_id;
5394 }
5395
5396 session->chunk_being_archived = chunk_being_archived;
5397 chunk_being_archived = NULL;
5398 if (!quiet_rotation) {
5399 ret = notification_thread_command_session_rotation_ongoing(
5400 notification_thread_handle,
5401 session->name, session->uid, session->gid,
5402 ongoing_rotation_chunk_id);
5403 if (ret != LTTNG_OK) {
5404 ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
5405 session->name);
5406 cmd_ret = ret;
5407 }
5408 }
5409
5410 DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
5411 session->name, ongoing_rotation_chunk_id);
5412 end:
5413 lttng_trace_chunk_put(new_trace_chunk);
5414 lttng_trace_chunk_put(chunk_being_archived);
5415 ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
5416 return ret;
5417 error:
5418 if (session_reset_rotation_state(session,
5419 LTTNG_ROTATION_STATE_ERROR)) {
5420 ERR("Failed to reset rotation state of session \"%s\"",
5421 session->name);
5422 }
5423 goto end;
5424 }
5425
5426 /*
5427 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
5428 *
5429 * Check if the session has finished its rotation.
5430 *
5431 * Return LTTNG_OK on success or else an LTTNG_ERR code.
5432 */
5433 int cmd_rotate_get_info(struct ltt_session *session,
5434 struct lttng_rotation_get_info_return *info_return,
5435 uint64_t rotation_id)
5436 {
5437 enum lttng_error_code cmd_ret = LTTNG_OK;
5438 enum lttng_rotation_state rotation_state;
5439
5440 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
5441 session->most_recent_chunk_id.value);
5442
5443 if (session->chunk_being_archived) {
5444 enum lttng_trace_chunk_status chunk_status;
5445 uint64_t chunk_id;
5446
5447 chunk_status = lttng_trace_chunk_get_id(
5448 session->chunk_being_archived,
5449 &chunk_id);
5450 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5451
5452 rotation_state = rotation_id == chunk_id ?
5453 LTTNG_ROTATION_STATE_ONGOING :
5454 LTTNG_ROTATION_STATE_EXPIRED;
5455 } else {
5456 if (session->last_archived_chunk_id.is_set &&
5457 rotation_id != session->last_archived_chunk_id.value) {
5458 rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
5459 } else {
5460 rotation_state = session->rotation_state;
5461 }
5462 }
5463
5464 switch (rotation_state) {
5465 case LTTNG_ROTATION_STATE_NO_ROTATION:
5466 DBG("Reporting that no rotation has occurred within the lifetime of session \"%s\"",
5467 session->name);
5468 goto end;
5469 case LTTNG_ROTATION_STATE_EXPIRED:
5470 DBG("Reporting that the rotation state of rotation id %" PRIu64 " of session \"%s\" has expired",
5471 rotation_id, session->name);
5472 break;
5473 case LTTNG_ROTATION_STATE_ONGOING:
5474 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
5475 rotation_id, session->name);
5476 break;
5477 case LTTNG_ROTATION_STATE_COMPLETED:
5478 {
5479 int fmt_ret;
5480 char *chunk_path;
5481 char *current_tracing_path_reply;
5482 size_t current_tracing_path_reply_len;
5483
5484 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
5485 rotation_id, session->name);
5486
5487 switch (session_get_consumer_destination_type(session)) {
5488 case CONSUMER_DST_LOCAL:
5489 current_tracing_path_reply =
5490 info_return->location.local.absolute_path;
5491 current_tracing_path_reply_len =
5492 sizeof(info_return->location.local.absolute_path);
5493 info_return->location_type =
5494 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
5495 fmt_ret = asprintf(&chunk_path,
5496 "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
5497 session_get_base_path(session),
5498 session->last_archived_chunk_name);
5499 if (fmt_ret == -1) {
5500 PERROR("Failed to format the path of the last archived trace chunk");
5501 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5502 cmd_ret = LTTNG_ERR_UNK;
5503 goto end;
5504 }
5505 break;
5506 case CONSUMER_DST_NET:
5507 {
5508 uint16_t ctrl_port, data_port;
5509
5510 current_tracing_path_reply =
5511 info_return->location.relay.relative_path;
5512 current_tracing_path_reply_len =
5513 sizeof(info_return->location.relay.relative_path);
5514 /* Currently the only supported relay protocol. */
5515 info_return->location.relay.protocol =
5516 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
5517
5518 fmt_ret = lttng_strncpy(info_return->location.relay.host,
5519 session_get_net_consumer_hostname(session),
5520 sizeof(info_return->location.relay.host));
5521 if (fmt_ret) {
5522 ERR("Failed to copy host name to rotate_get_info reply");
5523 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5524 cmd_ret = LTTNG_ERR_SET_URL;
5525 goto end;
5526 }
5527
5528 session_get_net_consumer_ports(session, &ctrl_port, &data_port);
5529 info_return->location.relay.ports.control = ctrl_port;
5530 info_return->location.relay.ports.data = data_port;
5531 info_return->location_type =
5532 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
5533 chunk_path = strdup(session->last_chunk_path);
5534 if (!chunk_path) {
5535 ERR("Failed to allocate the path of the last archived trace chunk");
5536 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5537 cmd_ret = LTTNG_ERR_UNK;
5538 goto end;
5539 }
5540 break;
5541 }
5542 default:
5543 abort();
5544 }
5545
5546 fmt_ret = lttng_strncpy(current_tracing_path_reply,
5547 chunk_path, current_tracing_path_reply_len);
5548 free(chunk_path);
5549 if (fmt_ret) {
5550 ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
5551 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5552 cmd_ret = LTTNG_ERR_UNK;
5553 goto end;
5554 }
5555
5556 break;
5557 }
5558 case LTTNG_ROTATION_STATE_ERROR:
5559 DBG("Reporting that an error occurred during rotation %" PRIu64 " of session \"%s\"",
5560 rotation_id, session->name);
5561 break;
5562 default:
5563 abort();
5564 }
5565
5566 cmd_ret = LTTNG_OK;
5567 end:
5568 info_return->status = (int32_t) rotation_state;
5569 return cmd_ret;
5570 }
5571
5572 /*
5573 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
5574 *
5575 * Configure the automatic rotation parameters.
5576 * 'activate' to true means activate the rotation schedule type with 'new_value'.
5577 * 'activate' to false means deactivate the rotation schedule and validate that
5578 * 'new_value' has the same value as the currently active value.
5579 *
5580 * Return 0 on success or else a positive LTTNG_ERR code.
5581 */
5582 int cmd_rotation_set_schedule(struct ltt_session *session,
5583 bool activate, enum lttng_rotation_schedule_type schedule_type,
5584 uint64_t new_value,
5585 struct notification_thread_handle *notification_thread_handle)
5586 {
5587 int ret;
5588 uint64_t *parameter_value;
5589
5590 assert(session);
5591
5592 DBG("Cmd rotate set schedule session %s", session->name);
5593
5594 if (session->live_timer || !session->output_traces) {
5595 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
5596 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5597 goto end;
5598 }
5599
5600 switch (schedule_type) {
5601 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5602 parameter_value = &session->rotate_size;
5603 break;
5604 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5605 parameter_value = &session->rotate_timer_period;
5606 if (new_value >= UINT_MAX) {
5607 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
5608 new_value, UINT_MAX);
5609 ret = LTTNG_ERR_INVALID;
5610 goto end;
5611 }
5612 break;
5613 default:
5614 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
5615 ret = LTTNG_ERR_INVALID;
5616 goto end;
5617 }
5618
5619 /* Improper use of the API. */
5620 if (new_value == -1ULL) {
5621 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
5622 ret = LTTNG_ERR_INVALID;
5623 goto end;
5624 }
5625
5626 /*
5627 * As indicated in struct ltt_session's comments, a value of == 0 means
5628 * this schedule rotation type is not in use.
5629 *
5630 * Reject the command if we were asked to activate a schedule that was
5631 * already active.
5632 */
5633 if (activate && *parameter_value != 0) {
5634 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
5635 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
5636 goto end;
5637 }
5638
5639 /*
5640 * Reject the command if we were asked to deactivate a schedule that was
5641 * not active.
5642 */
5643 if (!activate && *parameter_value == 0) {
5644 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
5645 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5646 goto end;
5647 }
5648
5649 /*
5650 * Reject the command if we were asked to deactivate a schedule that
5651 * doesn't exist.
5652 */
5653 if (!activate && *parameter_value != new_value) {
5654 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
5655 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5656 goto end;
5657 }
5658
5659 *parameter_value = activate ? new_value : 0;
5660
5661 switch (schedule_type) {
5662 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5663 if (activate && session->active) {
5664 /*
5665 * Only start the timer if the session is active,
5666 * otherwise it will be started when the session starts.
5667 */
5668 ret = timer_session_rotation_schedule_timer_start(
5669 session, new_value);
5670 if (ret) {
5671 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
5672 ret = LTTNG_ERR_UNK;
5673 goto end;
5674 }
5675 } else {
5676 ret = timer_session_rotation_schedule_timer_stop(
5677 session);
5678 if (ret) {
5679 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
5680 ret = LTTNG_ERR_UNK;
5681 goto end;
5682 }
5683 }
5684 break;
5685 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5686 if (activate) {
5687 ret = subscribe_session_consumed_size_rotation(session,
5688 new_value, notification_thread_handle);
5689 if (ret) {
5690 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
5691 ret = LTTNG_ERR_UNK;
5692 goto end;
5693 }
5694 } else {
5695 ret = unsubscribe_session_consumed_size_rotation(session,
5696 notification_thread_handle);
5697 if (ret) {
5698 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
5699 ret = LTTNG_ERR_UNK;
5700 goto end;
5701 }
5702
5703 }
5704 break;
5705 default:
5706 /* Would have been caught before. */
5707 abort();
5708 }
5709
5710 ret = LTTNG_OK;
5711
5712 goto end;
5713
5714 end:
5715 return ret;
5716 }
5717
5718 /* Wait for a given path to be removed before continuing. */
5719 static enum lttng_error_code wait_on_path(void *path_data)
5720 {
5721 const char *shm_path = path_data;
5722
5723 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5724 shm_path);
5725 while (true) {
5726 int ret;
5727 struct stat st;
5728
5729 ret = stat(shm_path, &st);
5730 if (ret) {
5731 if (errno != ENOENT) {
5732 PERROR("stat() returned an error while checking for the existence of the shm path");
5733 } else {
5734 DBG("shm path no longer exists, completing the destruction of session");
5735 }
5736 break;
5737 } else {
5738 if (!S_ISDIR(st.st_mode)) {
5739 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5740 shm_path);
5741 break;
5742 }
5743 }
5744 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
5745 }
5746 return LTTNG_OK;
5747 }
5748
5749 /*
5750 * Returns a pointer to a handler to run on completion of a command.
5751 * Returns NULL if no handler has to be run for the last command executed.
5752 */
5753 const struct cmd_completion_handler *cmd_pop_completion_handler(void)
5754 {
5755 struct cmd_completion_handler *handler = current_completion_handler;
5756
5757 current_completion_handler = NULL;
5758 return handler;
5759 }
5760
5761 /*
5762 * Init command subsystem.
5763 */
5764 void cmd_init(void)
5765 {
5766 /*
5767 * Set network sequence index to 1 for streams to match a relayd
5768 * socket on the consumer side.
5769 */
5770 pthread_mutex_lock(&relayd_net_seq_idx_lock);
5771 relayd_net_seq_idx = 1;
5772 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
5773
5774 DBG("Command subsystem initialized");
5775 }
LTTng tools - Deliverables
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