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9ae4d1974293a9197362f92b244eaca8f3543aff
[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
10 #define _LGPL_SOURCE
11 #include <assert.h>
12 #include <inttypes.h>
13 #include <stdio.h>
14 #include <sys/stat.h>
15 #include <urcu/list.h>
16 #include <urcu/uatomic.h>
17
18 #include <common/buffer-view.h>
19 #include <common/common.h>
20 #include <common/compat/string.h>
21 #include <common/defaults.h>
22 #include <common/dynamic-buffer.h>
23 #include <common/kernel-ctl/kernel-ctl.h>
24 #include <common/payload-view.h>
25 #include <common/payload.h>
26 #include <common/relayd/relayd.h>
27 #include <common/sessiond-comm/sessiond-comm.h>
28 #include <common/string-utils/string-utils.h>
29 #include <common/trace-chunk.h>
30 #include <common/utils.h>
31 #include <lttng/action/action-internal.h>
32 #include <lttng/action/action.h>
33 #include <lttng/channel-internal.h>
34 #include <lttng/channel.h>
35 #include <lttng/condition/condition-internal.h>
36 #include <lttng/condition/condition.h>
37 #include <lttng/condition/event-rule-matches-internal.h>
38 #include <lttng/condition/event-rule-matches.h>
39 #include <lttng/error-query-internal.h>
40 #include <lttng/event-rule/event-rule-internal.h>
41 #include <lttng/event-rule/event-rule.h>
42 #include <lttng/location-internal.h>
43 #include <lttng/lttng-error.h>
44 #include <lttng/rotate-internal.h>
45 #include <lttng/session-descriptor-internal.h>
46 #include <lttng/session-internal.h>
47 #include <lttng/tracker.h>
48 #include <lttng/trigger/trigger-internal.h>
49 #include <lttng/userspace-probe-internal.h>
50
51 #include "agent-thread.h"
52 #include "agent.h"
53 #include "buffer-registry.h"
54 #include "channel.h"
55 #include "cmd.h"
56 #include "consumer.h"
57 #include "event-notifier-error-accounting.h"
58 #include "event.h"
59 #include "health-sessiond.h"
60 #include "kernel-consumer.h"
61 #include "kernel.h"
62 #include "lttng-sessiond.h"
63 #include "lttng-syscall.h"
64 #include "notification-thread-commands.h"
65 #include "notification-thread.h"
66 #include "rotate.h"
67 #include "rotation-thread.h"
68 #include "session.h"
69 #include "timer.h"
70 #include "tracker.h"
71 #include "utils.h"
72
73 /* Sleep for 100ms between each check for the shm path's deletion. */
74 #define SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US 100000
75
76 struct cmd_destroy_session_reply_context {
77 int reply_sock_fd;
78 bool implicit_rotation_on_destroy;
79 /*
80 * Indicates whether or not an error occurred while launching the
81 * destruction of a session.
82 */
83 enum lttng_error_code destruction_status;
84 };
85
86 static enum lttng_error_code wait_on_path(void *path);
87
88 /*
89 * Command completion handler that is used by the destroy command
90 * when a session that has a non-default shm_path is being destroyed.
91 *
92 * See comment in cmd_destroy_session() for the rationale.
93 */
94 static struct destroy_completion_handler {
95 struct cmd_completion_handler handler;
96 char shm_path[member_sizeof(struct ltt_session, shm_path)];
97 } destroy_completion_handler = {
98 .handler = {
99 .run = wait_on_path,
100 .data = destroy_completion_handler.shm_path
101 },
102 .shm_path = { 0 },
103 };
104
105 static struct cmd_completion_handler *current_completion_handler;
106
107 /*
108 * Used to keep a unique index for each relayd socket created where this value
109 * is associated with streams on the consumer so it can match the right relayd
110 * to send to. It must be accessed with the relayd_net_seq_idx_lock
111 * held.
112 */
113 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
114 static uint64_t relayd_net_seq_idx;
115
116 static int validate_ust_event_name(const char *);
117 static int cmd_enable_event_internal(struct ltt_session *session,
118 const struct lttng_domain *domain,
119 char *channel_name, struct lttng_event *event,
120 char *filter_expression,
121 struct lttng_bytecode *filter,
122 struct lttng_event_exclusion *exclusion,
123 int wpipe);
124
125 /*
126 * Create a session path used by list_lttng_sessions for the case that the
127 * session consumer is on the network.
128 */
129 static int build_network_session_path(char *dst, size_t size,
130 struct ltt_session *session)
131 {
132 int ret, kdata_port, udata_port;
133 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
134 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
135
136 assert(session);
137 assert(dst);
138
139 memset(tmp_urls, 0, sizeof(tmp_urls));
140 memset(tmp_uurl, 0, sizeof(tmp_uurl));
141
142 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
143
144 if (session->kernel_session && session->kernel_session->consumer) {
145 kuri = &session->kernel_session->consumer->dst.net.control;
146 kdata_port = session->kernel_session->consumer->dst.net.data.port;
147 }
148
149 if (session->ust_session && session->ust_session->consumer) {
150 uuri = &session->ust_session->consumer->dst.net.control;
151 udata_port = session->ust_session->consumer->dst.net.data.port;
152 }
153
154 if (uuri == NULL && kuri == NULL) {
155 uri = &session->consumer->dst.net.control;
156 kdata_port = session->consumer->dst.net.data.port;
157 } else if (kuri && uuri) {
158 ret = uri_compare(kuri, uuri);
159 if (ret) {
160 /* Not Equal */
161 uri = kuri;
162 /* Build uuri URL string */
163 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
164 if (ret < 0) {
165 goto error;
166 }
167 } else {
168 uri = kuri;
169 }
170 } else if (kuri && uuri == NULL) {
171 uri = kuri;
172 } else if (uuri && kuri == NULL) {
173 uri = uuri;
174 }
175
176 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
177 if (ret < 0) {
178 goto error;
179 }
180
181 /*
182 * Do we have a UST url set. If yes, this means we have both kernel and UST
183 * to print.
184 */
185 if (*tmp_uurl != '\0') {
186 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
187 tmp_urls, kdata_port, tmp_uurl, udata_port);
188 } else {
189 int dport;
190 if (kuri || (!kuri && !uuri)) {
191 dport = kdata_port;
192 } else {
193 /* No kernel URI, use the UST port. */
194 dport = udata_port;
195 }
196 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
197 }
198
199 error:
200 return ret;
201 }
202
203 /*
204 * Get run-time attributes if the session has been started (discarded events,
205 * lost packets).
206 */
207 static int get_kernel_runtime_stats(struct ltt_session *session,
208 struct ltt_kernel_channel *kchan, uint64_t *discarded_events,
209 uint64_t *lost_packets)
210 {
211 int ret;
212
213 if (!session->has_been_started) {
214 ret = 0;
215 *discarded_events = 0;
216 *lost_packets = 0;
217 goto end;
218 }
219
220 ret = consumer_get_discarded_events(session->id, kchan->key,
221 session->kernel_session->consumer,
222 discarded_events);
223 if (ret < 0) {
224 goto end;
225 }
226
227 ret = consumer_get_lost_packets(session->id, kchan->key,
228 session->kernel_session->consumer,
229 lost_packets);
230 if (ret < 0) {
231 goto end;
232 }
233
234 end:
235 return ret;
236 }
237
238 /*
239 * Get run-time attributes if the session has been started (discarded events,
240 * lost packets).
241 */
242 static int get_ust_runtime_stats(struct ltt_session *session,
243 struct ltt_ust_channel *uchan, uint64_t *discarded_events,
244 uint64_t *lost_packets)
245 {
246 int ret;
247 struct ltt_ust_session *usess;
248
249 if (!discarded_events || !lost_packets) {
250 ret = -1;
251 goto end;
252 }
253
254 usess = session->ust_session;
255 assert(discarded_events);
256 assert(lost_packets);
257
258 if (!usess || !session->has_been_started) {
259 *discarded_events = 0;
260 *lost_packets = 0;
261 ret = 0;
262 goto end;
263 }
264
265 if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
266 ret = ust_app_uid_get_channel_runtime_stats(usess->id,
267 &usess->buffer_reg_uid_list,
268 usess->consumer, uchan->id,
269 uchan->attr.overwrite,
270 discarded_events,
271 lost_packets);
272 } else if (usess->buffer_type == LTTNG_BUFFER_PER_PID) {
273 ret = ust_app_pid_get_channel_runtime_stats(usess,
274 uchan, usess->consumer,
275 uchan->attr.overwrite,
276 discarded_events,
277 lost_packets);
278 if (ret < 0) {
279 goto end;
280 }
281 *discarded_events += uchan->per_pid_closed_app_discarded;
282 *lost_packets += uchan->per_pid_closed_app_lost;
283 } else {
284 ERR("Unsupported buffer type");
285 assert(0);
286 ret = -1;
287 goto end;
288 }
289
290 end:
291 return ret;
292 }
293
294 /*
295 * Fill lttng_channel array of all channels.
296 */
297 static ssize_t list_lttng_channels(enum lttng_domain_type domain,
298 struct ltt_session *session, struct lttng_channel *channels,
299 struct lttng_channel_extended *chan_exts)
300 {
301 int i = 0, ret = 0;
302 struct ltt_kernel_channel *kchan;
303
304 DBG("Listing channels for session %s", session->name);
305
306 switch (domain) {
307 case LTTNG_DOMAIN_KERNEL:
308 /* Kernel channels */
309 if (session->kernel_session != NULL) {
310 cds_list_for_each_entry(kchan,
311 &session->kernel_session->channel_list.head, list) {
312 uint64_t discarded_events, lost_packets;
313 struct lttng_channel_extended *extended;
314
315 extended = (struct lttng_channel_extended *)
316 kchan->channel->attr.extended.ptr;
317
318 ret = get_kernel_runtime_stats(session, kchan,
319 &discarded_events, &lost_packets);
320 if (ret < 0) {
321 goto end;
322 }
323 /* Copy lttng_channel struct to array */
324 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
325 channels[i].enabled = kchan->enabled;
326 chan_exts[i].discarded_events =
327 discarded_events;
328 chan_exts[i].lost_packets = lost_packets;
329 chan_exts[i].monitor_timer_interval =
330 extended->monitor_timer_interval;
331 chan_exts[i].blocking_timeout = 0;
332 i++;
333 }
334 }
335 break;
336 case LTTNG_DOMAIN_UST:
337 {
338 struct lttng_ht_iter iter;
339 struct ltt_ust_channel *uchan;
340
341 rcu_read_lock();
342 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
343 &iter.iter, uchan, node.node) {
344 uint64_t discarded_events = 0, lost_packets = 0;
345
346 if (lttng_strncpy(channels[i].name, uchan->name,
347 LTTNG_SYMBOL_NAME_LEN)) {
348 break;
349 }
350 channels[i].attr.overwrite = uchan->attr.overwrite;
351 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
352 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
353 channels[i].attr.switch_timer_interval =
354 uchan->attr.switch_timer_interval;
355 channels[i].attr.read_timer_interval =
356 uchan->attr.read_timer_interval;
357 channels[i].enabled = uchan->enabled;
358 channels[i].attr.tracefile_size = uchan->tracefile_size;
359 channels[i].attr.tracefile_count = uchan->tracefile_count;
360
361 /*
362 * Map enum lttng_ust_output to enum lttng_event_output.
363 */
364 switch (uchan->attr.output) {
365 case LTTNG_UST_ABI_MMAP:
366 channels[i].attr.output = LTTNG_EVENT_MMAP;
367 break;
368 default:
369 /*
370 * LTTNG_UST_MMAP is the only supported UST
371 * output mode.
372 */
373 assert(0);
374 break;
375 }
376
377 chan_exts[i].monitor_timer_interval =
378 uchan->monitor_timer_interval;
379 chan_exts[i].blocking_timeout =
380 uchan->attr.u.s.blocking_timeout;
381
382 ret = get_ust_runtime_stats(session, uchan,
383 &discarded_events, &lost_packets);
384 if (ret < 0) {
385 break;
386 }
387 chan_exts[i].discarded_events = discarded_events;
388 chan_exts[i].lost_packets = lost_packets;
389 i++;
390 }
391 rcu_read_unlock();
392 break;
393 }
394 default:
395 break;
396 }
397
398 end:
399 if (ret < 0) {
400 return -LTTNG_ERR_FATAL;
401 } else {
402 return LTTNG_OK;
403 }
404 }
405
406 static int append_extended_info(const char *filter_expression,
407 struct lttng_event_exclusion *exclusion,
408 struct lttng_userspace_probe_location *probe_location,
409 struct lttng_payload *payload)
410 {
411 int ret = 0;
412 size_t filter_len = 0;
413 size_t nb_exclusions = 0;
414 size_t userspace_probe_location_len = 0;
415 struct lttcomm_event_extended_header extended_header = {};
416 struct lttcomm_event_extended_header *p_extended_header;
417 const size_t original_payload_size = payload->buffer.size;
418
419 ret = lttng_dynamic_buffer_append(&payload->buffer, &extended_header,
420 sizeof(extended_header));
421 if (ret) {
422 goto end;
423 }
424
425 if (filter_expression) {
426 filter_len = strlen(filter_expression) + 1;
427 ret = lttng_dynamic_buffer_append(&payload->buffer,
428 filter_expression, filter_len);
429 if (ret) {
430 goto end;
431 }
432 }
433
434 if (exclusion) {
435 const size_t len = exclusion->count * LTTNG_SYMBOL_NAME_LEN;
436
437 nb_exclusions = exclusion->count;
438
439 ret = lttng_dynamic_buffer_append(
440 &payload->buffer, &exclusion->names, len);
441 if (ret) {
442 goto end;
443 }
444 }
445
446 if (probe_location) {
447 const size_t size_before_probe = payload->buffer.size;
448
449 ret = lttng_userspace_probe_location_serialize(probe_location,
450 payload);
451 if (ret < 0) {
452 ret = -1;
453 goto end;
454 }
455
456 userspace_probe_location_len =
457 payload->buffer.size - size_before_probe;
458 }
459
460 /* Set header fields */
461 p_extended_header = (struct lttcomm_event_extended_header *)
462 (payload->buffer.data + original_payload_size);
463
464 p_extended_header->filter_len = filter_len;
465 p_extended_header->nb_exclusions = nb_exclusions;
466 p_extended_header->userspace_probe_location_len =
467 userspace_probe_location_len;
468
469 ret = 0;
470 end:
471 return ret;
472 }
473
474 /*
475 * Create a list of agent domain events.
476 *
477 * Return number of events in list on success or else a negative value.
478 */
479 static int list_lttng_agent_events(struct agent *agt,
480 struct lttng_payload *payload)
481 {
482 int nb_events = 0, ret = 0;
483 const struct agent_event *agent_event;
484 struct lttng_ht_iter iter;
485
486 assert(agt);
487
488 DBG3("Listing agent events");
489
490 rcu_read_lock();
491 cds_lfht_for_each_entry (
492 agt->events->ht, &iter.iter, agent_event, node.node) {
493 struct lttng_event event = {
494 .enabled = AGENT_EVENT_IS_ENABLED(agent_event),
495 .loglevel = agent_event->loglevel_value,
496 .loglevel_type = agent_event->loglevel_type,
497 };
498
499 ret = lttng_strncpy(event.name, agent_event->name, sizeof(event.name));
500 if (ret) {
501 /* Internal error, invalid name. */
502 ERR("Invalid event name while listing agent events: '%s' exceeds the maximal allowed length of %zu bytes",
503 agent_event->name, sizeof(event.name));
504 ret = -LTTNG_ERR_UNK;
505 goto end;
506 }
507
508 ret = lttng_dynamic_buffer_append(
509 &payload->buffer, &event, sizeof(event));
510 if (ret) {
511 ERR("Failed to append event to payload");
512 ret = -LTTNG_ERR_NOMEM;
513 goto end;
514 }
515
516 nb_events++;
517 }
518
519 cds_lfht_for_each_entry (
520 agt->events->ht, &iter.iter, agent_event, node.node) {
521 /* Append extended info. */
522 ret = append_extended_info(agent_event->filter_expression, NULL,
523 NULL, payload);
524 if (ret) {
525 ERR("Failed to append extended event info to payload");
526 ret = -LTTNG_ERR_NOMEM;
527 goto end;
528 }
529 }
530
531 ret = nb_events;
532 end:
533 rcu_read_unlock();
534 return ret;
535 }
536
537 /*
538 * Create a list of ust global domain events.
539 */
540 static int list_lttng_ust_global_events(char *channel_name,
541 struct ltt_ust_domain_global *ust_global,
542 struct lttng_payload *payload)
543 {
544 int ret = 0;
545 unsigned int nb_events = 0;
546 struct lttng_ht_iter iter;
547 const struct lttng_ht_node_str *node;
548 const struct ltt_ust_channel *uchan;
549 const struct ltt_ust_event *uevent;
550
551 DBG("Listing UST global events for channel %s", channel_name);
552
553 rcu_read_lock();
554
555 lttng_ht_lookup(ust_global->channels, (void *) channel_name, &iter);
556 node = lttng_ht_iter_get_node_str(&iter);
557 if (node == NULL) {
558 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
559 goto end;
560 }
561
562 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
563
564 DBG3("Listing UST global events");
565
566 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
567 struct lttng_event event = {};
568
569 if (uevent->internal) {
570 continue;
571 }
572
573 ret = lttng_strncpy(event.name, uevent->attr.name, sizeof(event.name));
574 if (ret) {
575 /* Internal error, invalid name. */
576 ERR("Invalid event name while listing user space tracer events: '%s' exceeds the maximal allowed length of %zu bytes",
577 uevent->attr.name, sizeof(event.name));
578 ret = -LTTNG_ERR_UNK;
579 goto end;
580 }
581
582 event.enabled = uevent->enabled;
583
584 switch (uevent->attr.instrumentation) {
585 case LTTNG_UST_ABI_TRACEPOINT:
586 event.type = LTTNG_EVENT_TRACEPOINT;
587 break;
588 case LTTNG_UST_ABI_PROBE:
589 event.type = LTTNG_EVENT_PROBE;
590 break;
591 case LTTNG_UST_ABI_FUNCTION:
592 event.type = LTTNG_EVENT_FUNCTION;
593 break;
594 }
595
596 event.loglevel = uevent->attr.loglevel;
597 switch (uevent->attr.loglevel_type) {
598 case LTTNG_UST_ABI_LOGLEVEL_ALL:
599 event.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
600 break;
601 case LTTNG_UST_ABI_LOGLEVEL_RANGE:
602 event.loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
603 break;
604 case LTTNG_UST_ABI_LOGLEVEL_SINGLE:
605 event.loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
606 break;
607 }
608
609 if (uevent->filter) {
610 event.filter = 1;
611 }
612
613 if (uevent->exclusion) {
614 event.exclusion = 1;
615 }
616
617 ret = lttng_dynamic_buffer_append(&payload->buffer, &event, sizeof(event));
618 if (ret) {
619 ERR("Failed to append event to payload");
620 ret = -LTTNG_ERR_NOMEM;
621 goto end;
622 }
623
624 nb_events++;
625 }
626
627 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
628 /* Append extended info. */
629 ret = append_extended_info(uevent->filter_expression,
630 uevent->exclusion, NULL, payload);
631 if (ret) {
632 ERR("Failed to append extended event info to payload");
633 ret = -LTTNG_ERR_FATAL;
634 goto end;
635 }
636 }
637
638 ret = nb_events;
639 end:
640 rcu_read_unlock();
641 return ret;
642 }
643
644 /*
645 * Fill lttng_event array of all kernel events in the channel.
646 */
647 static int list_lttng_kernel_events(char *channel_name,
648 struct ltt_kernel_session *kernel_session,
649 struct lttng_payload *payload)
650 {
651 int ret;
652 unsigned int nb_event;
653 const struct ltt_kernel_event *kevent;
654 const struct ltt_kernel_channel *kchan;
655
656 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
657 if (kchan == NULL) {
658 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
659 goto error;
660 }
661
662 nb_event = kchan->event_count;
663
664 DBG("Listing events for channel %s", kchan->channel->name);
665
666 /* Kernel channels */
667 cds_list_for_each_entry(kevent, &kchan->events_list.head , list) {
668 struct lttng_event event = {};
669
670 ret = lttng_strncpy(event.name, kevent->event->name, sizeof(event.name));
671 if (ret) {
672 /* Internal error, invalid name. */
673 ERR("Invalid event name while listing kernel events: '%s' exceeds the maximal allowed length of %zu bytes",
674 kevent->event->name,
675 sizeof(event.name));
676 ret = -LTTNG_ERR_UNK;
677 goto end;
678 }
679
680 event.enabled = kevent->enabled;
681 event.filter = (unsigned char) !!kevent->filter_expression;
682
683 switch (kevent->event->instrumentation) {
684 case LTTNG_KERNEL_ABI_TRACEPOINT:
685 event.type = LTTNG_EVENT_TRACEPOINT;
686 break;
687 case LTTNG_KERNEL_ABI_KRETPROBE:
688 event.type = LTTNG_EVENT_FUNCTION;
689 memcpy(&event.attr.probe, &kevent->event->u.kprobe,
690 sizeof(struct lttng_kernel_abi_kprobe));
691 break;
692 case LTTNG_KERNEL_ABI_KPROBE:
693 event.type = LTTNG_EVENT_PROBE;
694 memcpy(&event.attr.probe, &kevent->event->u.kprobe,
695 sizeof(struct lttng_kernel_abi_kprobe));
696 break;
697 case LTTNG_KERNEL_ABI_UPROBE:
698 event.type = LTTNG_EVENT_USERSPACE_PROBE;
699 break;
700 case LTTNG_KERNEL_ABI_FUNCTION:
701 event.type = LTTNG_EVENT_FUNCTION;
702 memcpy(&event.attr.ftrace, &kevent->event->u.ftrace,
703 sizeof(struct lttng_kernel_abi_function));
704 break;
705 case LTTNG_KERNEL_ABI_NOOP:
706 event.type = LTTNG_EVENT_NOOP;
707 break;
708 case LTTNG_KERNEL_ABI_SYSCALL:
709 event.type = LTTNG_EVENT_SYSCALL;
710 break;
711 case LTTNG_KERNEL_ABI_ALL:
712 /* fall-through. */
713 default:
714 assert(0);
715 break;
716 }
717
718 ret = lttng_dynamic_buffer_append(
719 &payload->buffer, &event, sizeof(event));
720 if (ret) {
721 ERR("Failed to append event to payload");
722 ret = -LTTNG_ERR_NOMEM;
723 goto end;
724 }
725 }
726
727 cds_list_for_each_entry(kevent, &kchan->events_list.head , list) {
728 /* Append extended info. */
729 ret = append_extended_info(kevent->filter_expression, NULL,
730 kevent->userspace_probe_location, payload);
731 if (ret) {
732 DBG("Error appending extended info message");
733 ret = -LTTNG_ERR_FATAL;
734 goto error;
735 }
736 }
737
738 end:
739 return nb_event;
740 error:
741 return ret;
742 }
743
744 /*
745 * Add URI so the consumer output object. Set the correct path depending on the
746 * domain adding the default trace directory.
747 */
748 static enum lttng_error_code add_uri_to_consumer(
749 const struct ltt_session *session,
750 struct consumer_output *consumer,
751 struct lttng_uri *uri, enum lttng_domain_type domain)
752 {
753 int ret;
754 enum lttng_error_code ret_code = LTTNG_OK;
755
756 assert(uri);
757
758 if (consumer == NULL) {
759 DBG("No consumer detected. Don't add URI. Stopping.");
760 ret_code = LTTNG_ERR_NO_CONSUMER;
761 goto error;
762 }
763
764 switch (domain) {
765 case LTTNG_DOMAIN_KERNEL:
766 ret = lttng_strncpy(consumer->domain_subdir,
767 DEFAULT_KERNEL_TRACE_DIR,
768 sizeof(consumer->domain_subdir));
769 break;
770 case LTTNG_DOMAIN_UST:
771 ret = lttng_strncpy(consumer->domain_subdir,
772 DEFAULT_UST_TRACE_DIR,
773 sizeof(consumer->domain_subdir));
774 break;
775 default:
776 /*
777 * This case is possible is we try to add the URI to the global
778 * tracing session consumer object which in this case there is
779 * no subdir.
780 */
781 memset(consumer->domain_subdir, 0,
782 sizeof(consumer->domain_subdir));
783 ret = 0;
784 }
785 if (ret) {
786 ERR("Failed to initialize consumer output domain subdirectory");
787 ret_code = LTTNG_ERR_FATAL;
788 goto error;
789 }
790
791 switch (uri->dtype) {
792 case LTTNG_DST_IPV4:
793 case LTTNG_DST_IPV6:
794 DBG2("Setting network URI to consumer");
795
796 if (consumer->type == CONSUMER_DST_NET) {
797 if ((uri->stype == LTTNG_STREAM_CONTROL &&
798 consumer->dst.net.control_isset) ||
799 (uri->stype == LTTNG_STREAM_DATA &&
800 consumer->dst.net.data_isset)) {
801 ret_code = LTTNG_ERR_URL_EXIST;
802 goto error;
803 }
804 } else {
805 memset(&consumer->dst, 0, sizeof(consumer->dst));
806 }
807
808 /* Set URI into consumer output object */
809 ret = consumer_set_network_uri(session, consumer, uri);
810 if (ret < 0) {
811 ret_code = -ret;
812 goto error;
813 } else if (ret == 1) {
814 /*
815 * URI was the same in the consumer so we do not append the subdir
816 * again so to not duplicate output dir.
817 */
818 ret_code = LTTNG_OK;
819 goto error;
820 }
821 break;
822 case LTTNG_DST_PATH:
823 if (*uri->dst.path != '/' || strstr(uri->dst.path, "../")) {
824 ret_code = LTTNG_ERR_INVALID;
825 goto error;
826 }
827 DBG2("Setting trace directory path from URI to %s",
828 uri->dst.path);
829 memset(&consumer->dst, 0, sizeof(consumer->dst));
830
831 ret = lttng_strncpy(consumer->dst.session_root_path,
832 uri->dst.path,
833 sizeof(consumer->dst.session_root_path));
834 if (ret) {
835 ret_code = LTTNG_ERR_FATAL;
836 goto error;
837 }
838 consumer->type = CONSUMER_DST_LOCAL;
839 break;
840 }
841
842 ret_code = LTTNG_OK;
843 error:
844 return ret_code;
845 }
846
847 /*
848 * Init tracing by creating trace directory and sending fds kernel consumer.
849 */
850 static int init_kernel_tracing(struct ltt_kernel_session *session)
851 {
852 int ret = 0;
853 struct lttng_ht_iter iter;
854 struct consumer_socket *socket;
855
856 assert(session);
857
858 rcu_read_lock();
859
860 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
861 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
862 socket, node.node) {
863 pthread_mutex_lock(socket->lock);
864 ret = kernel_consumer_send_session(socket, session);
865 pthread_mutex_unlock(socket->lock);
866 if (ret < 0) {
867 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
868 goto error;
869 }
870 }
871 }
872
873 error:
874 rcu_read_unlock();
875 return ret;
876 }
877
878 /*
879 * Create a socket to the relayd using the URI.
880 *
881 * On success, the relayd_sock pointer is set to the created socket.
882 * Else, it remains untouched and an LTTng error code is returned.
883 */
884 static enum lttng_error_code create_connect_relayd(struct lttng_uri *uri,
885 struct lttcomm_relayd_sock **relayd_sock,
886 struct consumer_output *consumer)
887 {
888 int ret;
889 enum lttng_error_code status = LTTNG_OK;
890 struct lttcomm_relayd_sock *rsock;
891
892 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
893 RELAYD_VERSION_COMM_MINOR);
894 if (!rsock) {
895 status = LTTNG_ERR_FATAL;
896 goto error;
897 }
898
899 /*
900 * Connect to relayd so we can proceed with a session creation. This call
901 * can possibly block for an arbitrary amount of time to set the health
902 * state to be in poll execution.
903 */
904 health_poll_entry();
905 ret = relayd_connect(rsock);
906 health_poll_exit();
907 if (ret < 0) {
908 ERR("Unable to reach lttng-relayd");
909 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
910 goto free_sock;
911 }
912
913 /* Create socket for control stream. */
914 if (uri->stype == LTTNG_STREAM_CONTROL) {
915 uint64_t result_flags;
916
917 DBG3("Creating relayd stream socket from URI");
918
919 /* Check relayd version */
920 ret = relayd_version_check(rsock);
921 if (ret == LTTNG_ERR_RELAYD_VERSION_FAIL) {
922 status = LTTNG_ERR_RELAYD_VERSION_FAIL;
923 goto close_sock;
924 } else if (ret < 0) {
925 ERR("Unable to reach lttng-relayd");
926 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
927 goto close_sock;
928 }
929 consumer->relay_major_version = rsock->major;
930 consumer->relay_minor_version = rsock->minor;
931 ret = relayd_get_configuration(rsock, 0,
932 &result_flags);
933 if (ret < 0) {
934 ERR("Unable to get relayd configuration");
935 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
936 goto close_sock;
937 }
938 if (result_flags & LTTCOMM_RELAYD_CONFIGURATION_FLAG_CLEAR_ALLOWED) {
939 consumer->relay_allows_clear = true;
940 }
941 } else if (uri->stype == LTTNG_STREAM_DATA) {
942 DBG3("Creating relayd data socket from URI");
943 } else {
944 /* Command is not valid */
945 ERR("Relayd invalid stream type: %d", uri->stype);
946 status = LTTNG_ERR_INVALID;
947 goto close_sock;
948 }
949
950 *relayd_sock = rsock;
951
952 return status;
953
954 close_sock:
955 /* The returned value is not useful since we are on an error path. */
956 (void) relayd_close(rsock);
957 free_sock:
958 free(rsock);
959 error:
960 return status;
961 }
962
963 /*
964 * Connect to the relayd using URI and send the socket to the right consumer.
965 *
966 * The consumer socket lock must be held by the caller.
967 *
968 * Returns LTTNG_OK on success or an LTTng error code on failure.
969 */
970 static enum lttng_error_code send_consumer_relayd_socket(
971 unsigned int session_id,
972 struct lttng_uri *relayd_uri,
973 struct consumer_output *consumer,
974 struct consumer_socket *consumer_sock,
975 const char *session_name, const char *hostname,
976 const char *base_path, int session_live_timer,
977 const uint64_t *current_chunk_id,
978 time_t session_creation_time,
979 bool session_name_contains_creation_time)
980 {
981 int ret;
982 struct lttcomm_relayd_sock *rsock = NULL;
983 enum lttng_error_code status;
984
985 /* Connect to relayd and make version check if uri is the control. */
986 status = create_connect_relayd(relayd_uri, &rsock, consumer);
987 if (status != LTTNG_OK) {
988 goto relayd_comm_error;
989 }
990 assert(rsock);
991
992 /* Set the network sequence index if not set. */
993 if (consumer->net_seq_index == (uint64_t) -1ULL) {
994 pthread_mutex_lock(&relayd_net_seq_idx_lock);
995 /*
996 * Increment net_seq_idx because we are about to transfer the
997 * new relayd socket to the consumer.
998 * Assign unique key so the consumer can match streams.
999 */
1000 consumer->net_seq_index = ++relayd_net_seq_idx;
1001 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
1002 }
1003
1004 /* Send relayd socket to consumer. */
1005 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
1006 relayd_uri->stype, session_id,
1007 session_name, hostname, base_path,
1008 session_live_timer, current_chunk_id,
1009 session_creation_time, session_name_contains_creation_time);
1010 if (ret < 0) {
1011 status = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
1012 goto close_sock;
1013 }
1014
1015 /* Flag that the corresponding socket was sent. */
1016 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
1017 consumer_sock->control_sock_sent = 1;
1018 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
1019 consumer_sock->data_sock_sent = 1;
1020 }
1021
1022 /*
1023 * Close socket which was dup on the consumer side. The session daemon does
1024 * NOT keep track of the relayd socket(s) once transfer to the consumer.
1025 */
1026
1027 close_sock:
1028 if (status != LTTNG_OK) {
1029 /*
1030 * The consumer output for this session should not be used anymore
1031 * since the relayd connection failed thus making any tracing or/and
1032 * streaming not usable.
1033 */
1034 consumer->enabled = 0;
1035 }
1036 (void) relayd_close(rsock);
1037 free(rsock);
1038
1039 relayd_comm_error:
1040 return status;
1041 }
1042
1043 /*
1044 * Send both relayd sockets to a specific consumer and domain. This is a
1045 * helper function to facilitate sending the information to the consumer for a
1046 * session.
1047 *
1048 * The consumer socket lock must be held by the caller.
1049 *
1050 * Returns LTTNG_OK, or an LTTng error code on failure.
1051 */
1052 static enum lttng_error_code send_consumer_relayd_sockets(
1053 enum lttng_domain_type domain,
1054 unsigned int session_id, struct consumer_output *consumer,
1055 struct consumer_socket *sock, const char *session_name,
1056 const char *hostname, const char *base_path, int session_live_timer,
1057 const uint64_t *current_chunk_id, time_t session_creation_time,
1058 bool session_name_contains_creation_time)
1059 {
1060 enum lttng_error_code status = LTTNG_OK;
1061
1062 assert(consumer);
1063 assert(sock);
1064
1065 /* Sending control relayd socket. */
1066 if (!sock->control_sock_sent) {
1067 status = send_consumer_relayd_socket(session_id,
1068 &consumer->dst.net.control, consumer, sock,
1069 session_name, hostname, base_path, session_live_timer,
1070 current_chunk_id, session_creation_time,
1071 session_name_contains_creation_time);
1072 if (status != LTTNG_OK) {
1073 goto error;
1074 }
1075 }
1076
1077 /* Sending data relayd socket. */
1078 if (!sock->data_sock_sent) {
1079 status = send_consumer_relayd_socket(session_id,
1080 &consumer->dst.net.data, consumer, sock,
1081 session_name, hostname, base_path, session_live_timer,
1082 current_chunk_id, session_creation_time,
1083 session_name_contains_creation_time);
1084 if (status != LTTNG_OK) {
1085 goto error;
1086 }
1087 }
1088
1089 error:
1090 return status;
1091 }
1092
1093 /*
1094 * Setup relayd connections for a tracing session. First creates the socket to
1095 * the relayd and send them to the right domain consumer. Consumer type MUST be
1096 * network.
1097 */
1098 int cmd_setup_relayd(struct ltt_session *session)
1099 {
1100 int ret = LTTNG_OK;
1101 struct ltt_ust_session *usess;
1102 struct ltt_kernel_session *ksess;
1103 struct consumer_socket *socket;
1104 struct lttng_ht_iter iter;
1105 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
1106
1107 assert(session);
1108
1109 usess = session->ust_session;
1110 ksess = session->kernel_session;
1111
1112 DBG("Setting relayd for session %s", session->name);
1113
1114 rcu_read_lock();
1115 if (session->current_trace_chunk) {
1116 enum lttng_trace_chunk_status status = lttng_trace_chunk_get_id(
1117 session->current_trace_chunk, &current_chunk_id.value);
1118
1119 if (status == LTTNG_TRACE_CHUNK_STATUS_OK) {
1120 current_chunk_id.is_set = true;
1121 } else {
1122 ERR("Failed to get current trace chunk id");
1123 ret = LTTNG_ERR_UNK;
1124 goto error;
1125 }
1126 }
1127
1128 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1129 && usess->consumer->enabled) {
1130 /* For each consumer socket, send relayd sockets */
1131 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1132 socket, node.node) {
1133 pthread_mutex_lock(socket->lock);
1134 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1135 usess->consumer, socket,
1136 session->name, session->hostname,
1137 session->base_path,
1138 session->live_timer,
1139 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1140 session->creation_time,
1141 session->name_contains_creation_time);
1142 pthread_mutex_unlock(socket->lock);
1143 if (ret != LTTNG_OK) {
1144 goto error;
1145 }
1146 /* Session is now ready for network streaming. */
1147 session->net_handle = 1;
1148 }
1149 session->consumer->relay_major_version =
1150 usess->consumer->relay_major_version;
1151 session->consumer->relay_minor_version =
1152 usess->consumer->relay_minor_version;
1153 session->consumer->relay_allows_clear =
1154 usess->consumer->relay_allows_clear;
1155 }
1156
1157 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1158 && ksess->consumer->enabled) {
1159 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1160 socket, node.node) {
1161 pthread_mutex_lock(socket->lock);
1162 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1163 ksess->consumer, socket,
1164 session->name, session->hostname,
1165 session->base_path,
1166 session->live_timer,
1167 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1168 session->creation_time,
1169 session->name_contains_creation_time);
1170 pthread_mutex_unlock(socket->lock);
1171 if (ret != LTTNG_OK) {
1172 goto error;
1173 }
1174 /* Session is now ready for network streaming. */
1175 session->net_handle = 1;
1176 }
1177 session->consumer->relay_major_version =
1178 ksess->consumer->relay_major_version;
1179 session->consumer->relay_minor_version =
1180 ksess->consumer->relay_minor_version;
1181 session->consumer->relay_allows_clear =
1182 ksess->consumer->relay_allows_clear;
1183 }
1184
1185 error:
1186 rcu_read_unlock();
1187 return ret;
1188 }
1189
1190 /*
1191 * Start a kernel session by opening all necessary streams.
1192 */
1193 int start_kernel_session(struct ltt_kernel_session *ksess)
1194 {
1195 int ret;
1196 struct ltt_kernel_channel *kchan;
1197
1198 /* Open kernel metadata */
1199 if (ksess->metadata == NULL && ksess->output_traces) {
1200 ret = kernel_open_metadata(ksess);
1201 if (ret < 0) {
1202 ret = LTTNG_ERR_KERN_META_FAIL;
1203 goto error;
1204 }
1205 }
1206
1207 /* Open kernel metadata stream */
1208 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1209 ret = kernel_open_metadata_stream(ksess);
1210 if (ret < 0) {
1211 ERR("Kernel create metadata stream failed");
1212 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1213 goto error;
1214 }
1215 }
1216
1217 /* For each channel */
1218 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1219 if (kchan->stream_count == 0) {
1220 ret = kernel_open_channel_stream(kchan);
1221 if (ret < 0) {
1222 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1223 goto error;
1224 }
1225 /* Update the stream global counter */
1226 ksess->stream_count_global += ret;
1227 }
1228 }
1229
1230 /* Setup kernel consumer socket and send fds to it */
1231 ret = init_kernel_tracing(ksess);
1232 if (ret != 0) {
1233 ret = LTTNG_ERR_KERN_START_FAIL;
1234 goto error;
1235 }
1236
1237 /* This start the kernel tracing */
1238 ret = kernel_start_session(ksess);
1239 if (ret < 0) {
1240 ret = LTTNG_ERR_KERN_START_FAIL;
1241 goto error;
1242 }
1243
1244 /* Quiescent wait after starting trace */
1245 kernel_wait_quiescent();
1246
1247 ksess->active = 1;
1248
1249 ret = LTTNG_OK;
1250
1251 error:
1252 return ret;
1253 }
1254
1255 int stop_kernel_session(struct ltt_kernel_session *ksess)
1256 {
1257 struct ltt_kernel_channel *kchan;
1258 bool error_occurred = false;
1259 int ret;
1260
1261 if (!ksess || !ksess->active) {
1262 return LTTNG_OK;
1263 }
1264 DBG("Stopping kernel tracing");
1265
1266 ret = kernel_stop_session(ksess);
1267 if (ret < 0) {
1268 ret = LTTNG_ERR_KERN_STOP_FAIL;
1269 goto error;
1270 }
1271
1272 kernel_wait_quiescent();
1273
1274 /* Flush metadata after stopping (if exists) */
1275 if (ksess->metadata_stream_fd >= 0) {
1276 ret = kernel_metadata_flush_buffer(ksess->metadata_stream_fd);
1277 if (ret < 0) {
1278 ERR("Kernel metadata flush failed");
1279 error_occurred = true;
1280 }
1281 }
1282
1283 /* Flush all buffers after stopping */
1284 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1285 ret = kernel_flush_buffer(kchan);
1286 if (ret < 0) {
1287 ERR("Kernel flush buffer error");
1288 error_occurred = true;
1289 }
1290 }
1291
1292 ksess->active = 0;
1293 if (error_occurred) {
1294 ret = LTTNG_ERR_UNK;
1295 } else {
1296 ret = LTTNG_OK;
1297 }
1298 error:
1299 return ret;
1300 }
1301
1302 /*
1303 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1304 */
1305 int cmd_disable_channel(struct ltt_session *session,
1306 enum lttng_domain_type domain, char *channel_name)
1307 {
1308 int ret;
1309 struct ltt_ust_session *usess;
1310
1311 usess = session->ust_session;
1312
1313 rcu_read_lock();
1314
1315 switch (domain) {
1316 case LTTNG_DOMAIN_KERNEL:
1317 {
1318 ret = channel_kernel_disable(session->kernel_session,
1319 channel_name);
1320 if (ret != LTTNG_OK) {
1321 goto error;
1322 }
1323
1324 kernel_wait_quiescent();
1325 break;
1326 }
1327 case LTTNG_DOMAIN_UST:
1328 {
1329 struct ltt_ust_channel *uchan;
1330 struct lttng_ht *chan_ht;
1331
1332 chan_ht = usess->domain_global.channels;
1333
1334 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1335 if (uchan == NULL) {
1336 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1337 goto error;
1338 }
1339
1340 ret = channel_ust_disable(usess, uchan);
1341 if (ret != LTTNG_OK) {
1342 goto error;
1343 }
1344 break;
1345 }
1346 default:
1347 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1348 goto error;
1349 }
1350
1351 ret = LTTNG_OK;
1352
1353 error:
1354 rcu_read_unlock();
1355 return ret;
1356 }
1357
1358 /*
1359 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1360 *
1361 * The wpipe arguments is used as a notifier for the kernel thread.
1362 */
1363 int cmd_enable_channel(struct ltt_session *session,
1364 const struct lttng_domain *domain, const struct lttng_channel *_attr, int wpipe)
1365 {
1366 int ret;
1367 struct ltt_ust_session *usess = session->ust_session;
1368 struct lttng_ht *chan_ht;
1369 size_t len;
1370 struct lttng_channel attr;
1371
1372 assert(session);
1373 assert(_attr);
1374 assert(domain);
1375
1376 attr = *_attr;
1377 len = lttng_strnlen(attr.name, sizeof(attr.name));
1378
1379 /* Validate channel name */
1380 if (attr.name[0] == '.' ||
1381 memchr(attr.name, '/', len) != NULL) {
1382 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1383 goto end;
1384 }
1385
1386 DBG("Enabling channel %s for session %s", attr.name, session->name);
1387
1388 rcu_read_lock();
1389
1390 /*
1391 * Don't try to enable a channel if the session has been started at
1392 * some point in time before. The tracer does not allow it.
1393 */
1394 if (session->has_been_started) {
1395 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1396 goto error;
1397 }
1398
1399 /*
1400 * If the session is a live session, remove the switch timer, the
1401 * live timer does the same thing but sends also synchronisation
1402 * beacons for inactive streams.
1403 */
1404 if (session->live_timer > 0) {
1405 attr.attr.live_timer_interval = session->live_timer;
1406 attr.attr.switch_timer_interval = 0;
1407 }
1408
1409 /* Check for feature support */
1410 switch (domain->type) {
1411 case LTTNG_DOMAIN_KERNEL:
1412 {
1413 if (kernel_supports_ring_buffer_snapshot_sample_positions() != 1) {
1414 /* Sampling position of buffer is not supported */
1415 WARN("Kernel tracer does not support buffer monitoring. "
1416 "Setting the monitor interval timer to 0 "
1417 "(disabled) for channel '%s' of session '%s'",
1418 attr.name, session->name);
1419 lttng_channel_set_monitor_timer_interval(&attr, 0);
1420 }
1421 break;
1422 }
1423 case LTTNG_DOMAIN_UST:
1424 break;
1425 case LTTNG_DOMAIN_JUL:
1426 case LTTNG_DOMAIN_LOG4J:
1427 case LTTNG_DOMAIN_PYTHON:
1428 if (!agent_tracing_is_enabled()) {
1429 DBG("Attempted to enable a channel in an agent domain but the agent thread is not running");
1430 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
1431 goto error;
1432 }
1433 break;
1434 default:
1435 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1436 goto error;
1437 }
1438
1439 switch (domain->type) {
1440 case LTTNG_DOMAIN_KERNEL:
1441 {
1442 struct ltt_kernel_channel *kchan;
1443
1444 kchan = trace_kernel_get_channel_by_name(attr.name,
1445 session->kernel_session);
1446 if (kchan == NULL) {
1447 if (session->snapshot.nb_output > 0 ||
1448 session->snapshot_mode) {
1449 /* Enforce mmap output for snapshot sessions. */
1450 attr.attr.output = LTTNG_EVENT_MMAP;
1451 }
1452 ret = channel_kernel_create(session->kernel_session, &attr, wpipe);
1453 if (attr.name[0] != '\0') {
1454 session->kernel_session->has_non_default_channel = 1;
1455 }
1456 } else {
1457 ret = channel_kernel_enable(session->kernel_session, kchan);
1458 }
1459
1460 if (ret != LTTNG_OK) {
1461 goto error;
1462 }
1463
1464 kernel_wait_quiescent();
1465 break;
1466 }
1467 case LTTNG_DOMAIN_UST:
1468 case LTTNG_DOMAIN_JUL:
1469 case LTTNG_DOMAIN_LOG4J:
1470 case LTTNG_DOMAIN_PYTHON:
1471 {
1472 struct ltt_ust_channel *uchan;
1473
1474 /*
1475 * FIXME
1476 *
1477 * Current agent implementation limitations force us to allow
1478 * only one channel at once in "agent" subdomains. Each
1479 * subdomain has a default channel name which must be strictly
1480 * adhered to.
1481 */
1482 if (domain->type == LTTNG_DOMAIN_JUL) {
1483 if (strncmp(attr.name, DEFAULT_JUL_CHANNEL_NAME,
1484 LTTNG_SYMBOL_NAME_LEN)) {
1485 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1486 goto error;
1487 }
1488 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1489 if (strncmp(attr.name, DEFAULT_LOG4J_CHANNEL_NAME,
1490 LTTNG_SYMBOL_NAME_LEN)) {
1491 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1492 goto error;
1493 }
1494 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1495 if (strncmp(attr.name, DEFAULT_PYTHON_CHANNEL_NAME,
1496 LTTNG_SYMBOL_NAME_LEN)) {
1497 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1498 goto error;
1499 }
1500 }
1501
1502 chan_ht = usess->domain_global.channels;
1503
1504 uchan = trace_ust_find_channel_by_name(chan_ht, attr.name);
1505 if (uchan == NULL) {
1506 ret = channel_ust_create(usess, &attr, domain->buf_type);
1507 if (attr.name[0] != '\0') {
1508 usess->has_non_default_channel = 1;
1509 }
1510 } else {
1511 ret = channel_ust_enable(usess, uchan);
1512 }
1513 break;
1514 }
1515 default:
1516 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1517 goto error;
1518 }
1519
1520 if (ret == LTTNG_OK && attr.attr.output != LTTNG_EVENT_MMAP) {
1521 session->has_non_mmap_channel = true;
1522 }
1523 error:
1524 rcu_read_unlock();
1525 end:
1526 return ret;
1527 }
1528
1529 enum lttng_error_code cmd_process_attr_tracker_get_tracking_policy(
1530 struct ltt_session *session,
1531 enum lttng_domain_type domain,
1532 enum lttng_process_attr process_attr,
1533 enum lttng_tracking_policy *policy)
1534 {
1535 enum lttng_error_code ret_code = LTTNG_OK;
1536 const struct process_attr_tracker *tracker;
1537
1538 switch (domain) {
1539 case LTTNG_DOMAIN_KERNEL:
1540 if (!session->kernel_session) {
1541 ret_code = LTTNG_ERR_INVALID;
1542 goto end;
1543 }
1544 tracker = kernel_get_process_attr_tracker(
1545 session->kernel_session, process_attr);
1546 break;
1547 case LTTNG_DOMAIN_UST:
1548 if (!session->ust_session) {
1549 ret_code = LTTNG_ERR_INVALID;
1550 goto end;
1551 }
1552 tracker = trace_ust_get_process_attr_tracker(
1553 session->ust_session, process_attr);
1554 break;
1555 default:
1556 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1557 goto end;
1558 }
1559 if (tracker) {
1560 *policy = process_attr_tracker_get_tracking_policy(tracker);
1561 } else {
1562 ret_code = LTTNG_ERR_INVALID;
1563 }
1564 end:
1565 return ret_code;
1566 }
1567
1568 enum lttng_error_code cmd_process_attr_tracker_set_tracking_policy(
1569 struct ltt_session *session,
1570 enum lttng_domain_type domain,
1571 enum lttng_process_attr process_attr,
1572 enum lttng_tracking_policy policy)
1573 {
1574 enum lttng_error_code ret_code = LTTNG_OK;
1575
1576 switch (policy) {
1577 case LTTNG_TRACKING_POLICY_INCLUDE_SET:
1578 case LTTNG_TRACKING_POLICY_EXCLUDE_ALL:
1579 case LTTNG_TRACKING_POLICY_INCLUDE_ALL:
1580 break;
1581 default:
1582 ret_code = LTTNG_ERR_INVALID;
1583 goto end;
1584 }
1585
1586 switch (domain) {
1587 case LTTNG_DOMAIN_KERNEL:
1588 if (!session->kernel_session) {
1589 ret_code = LTTNG_ERR_INVALID;
1590 goto end;
1591 }
1592 ret_code = kernel_process_attr_tracker_set_tracking_policy(
1593 session->kernel_session, process_attr, policy);
1594 break;
1595 case LTTNG_DOMAIN_UST:
1596 if (!session->ust_session) {
1597 ret_code = LTTNG_ERR_INVALID;
1598 goto end;
1599 }
1600 ret_code = trace_ust_process_attr_tracker_set_tracking_policy(
1601 session->ust_session, process_attr, policy);
1602 break;
1603 default:
1604 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1605 break;
1606 }
1607 end:
1608 return ret_code;
1609 }
1610
1611 enum lttng_error_code cmd_process_attr_tracker_inclusion_set_add_value(
1612 struct ltt_session *session,
1613 enum lttng_domain_type domain,
1614 enum lttng_process_attr process_attr,
1615 const struct process_attr_value *value)
1616 {
1617 enum lttng_error_code ret_code = LTTNG_OK;
1618
1619 switch (domain) {
1620 case LTTNG_DOMAIN_KERNEL:
1621 if (!session->kernel_session) {
1622 ret_code = LTTNG_ERR_INVALID;
1623 goto end;
1624 }
1625 ret_code = kernel_process_attr_tracker_inclusion_set_add_value(
1626 session->kernel_session, process_attr, value);
1627 break;
1628 case LTTNG_DOMAIN_UST:
1629 if (!session->ust_session) {
1630 ret_code = LTTNG_ERR_INVALID;
1631 goto end;
1632 }
1633 ret_code = trace_ust_process_attr_tracker_inclusion_set_add_value(
1634 session->ust_session, process_attr, value);
1635 break;
1636 default:
1637 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1638 break;
1639 }
1640 end:
1641 return ret_code;
1642 }
1643
1644 enum lttng_error_code cmd_process_attr_tracker_inclusion_set_remove_value(
1645 struct ltt_session *session,
1646 enum lttng_domain_type domain,
1647 enum lttng_process_attr process_attr,
1648 const struct process_attr_value *value)
1649 {
1650 enum lttng_error_code ret_code = LTTNG_OK;
1651
1652 switch (domain) {
1653 case LTTNG_DOMAIN_KERNEL:
1654 if (!session->kernel_session) {
1655 ret_code = LTTNG_ERR_INVALID;
1656 goto end;
1657 }
1658 ret_code = kernel_process_attr_tracker_inclusion_set_remove_value(
1659 session->kernel_session, process_attr, value);
1660 break;
1661 case LTTNG_DOMAIN_UST:
1662 if (!session->ust_session) {
1663 ret_code = LTTNG_ERR_INVALID;
1664 goto end;
1665 }
1666 ret_code = trace_ust_process_attr_tracker_inclusion_set_remove_value(
1667 session->ust_session, process_attr, value);
1668 break;
1669 default:
1670 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1671 break;
1672 }
1673 end:
1674 return ret_code;
1675 }
1676
1677 enum lttng_error_code cmd_process_attr_tracker_get_inclusion_set(
1678 struct ltt_session *session,
1679 enum lttng_domain_type domain,
1680 enum lttng_process_attr process_attr,
1681 struct lttng_process_attr_values **values)
1682 {
1683 enum lttng_error_code ret_code = LTTNG_OK;
1684 const struct process_attr_tracker *tracker;
1685 enum process_attr_tracker_status status;
1686
1687 switch (domain) {
1688 case LTTNG_DOMAIN_KERNEL:
1689 if (!session->kernel_session) {
1690 ret_code = LTTNG_ERR_INVALID;
1691 goto end;
1692 }
1693 tracker = kernel_get_process_attr_tracker(
1694 session->kernel_session, process_attr);
1695 break;
1696 case LTTNG_DOMAIN_UST:
1697 if (!session->ust_session) {
1698 ret_code = LTTNG_ERR_INVALID;
1699 goto end;
1700 }
1701 tracker = trace_ust_get_process_attr_tracker(
1702 session->ust_session, process_attr);
1703 break;
1704 default:
1705 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1706 goto end;
1707 }
1708
1709 if (!tracker) {
1710 ret_code = LTTNG_ERR_INVALID;
1711 goto end;
1712 }
1713
1714 status = process_attr_tracker_get_inclusion_set(tracker, values);
1715 switch (status) {
1716 case PROCESS_ATTR_TRACKER_STATUS_OK:
1717 ret_code = LTTNG_OK;
1718 break;
1719 case PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY:
1720 ret_code = LTTNG_ERR_PROCESS_ATTR_TRACKER_INVALID_TRACKING_POLICY;
1721 break;
1722 case PROCESS_ATTR_TRACKER_STATUS_ERROR:
1723 ret_code = LTTNG_ERR_NOMEM;
1724 break;
1725 default:
1726 ret_code = LTTNG_ERR_UNK;
1727 break;
1728 }
1729
1730 end:
1731 return ret_code;
1732 }
1733
1734 /*
1735 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1736 */
1737 int cmd_disable_event(struct ltt_session *session,
1738 enum lttng_domain_type domain, const char *channel_name,
1739 const struct lttng_event *event)
1740 {
1741 int ret;
1742 const char *event_name;
1743
1744 DBG("Disable event command for event \'%s\'", event->name);
1745
1746 event_name = event->name;
1747
1748 /* Error out on unhandled search criteria */
1749 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1750 || event->pid || event->filter || event->exclusion) {
1751 ret = LTTNG_ERR_UNK;
1752 goto error;
1753 }
1754
1755 rcu_read_lock();
1756
1757 switch (domain) {
1758 case LTTNG_DOMAIN_KERNEL:
1759 {
1760 struct ltt_kernel_channel *kchan;
1761 struct ltt_kernel_session *ksess;
1762
1763 ksess = session->kernel_session;
1764
1765 /*
1766 * If a non-default channel has been created in the
1767 * session, explicitely require that -c chan_name needs
1768 * to be provided.
1769 */
1770 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1771 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1772 goto error_unlock;
1773 }
1774
1775 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1776 if (kchan == NULL) {
1777 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1778 goto error_unlock;
1779 }
1780
1781 switch (event->type) {
1782 case LTTNG_EVENT_ALL:
1783 case LTTNG_EVENT_TRACEPOINT:
1784 case LTTNG_EVENT_SYSCALL:
1785 case LTTNG_EVENT_PROBE:
1786 case LTTNG_EVENT_FUNCTION:
1787 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1788 if (event_name[0] == '\0') {
1789 ret = event_kernel_disable_event(kchan,
1790 NULL, event->type);
1791 } else {
1792 ret = event_kernel_disable_event(kchan,
1793 event_name, event->type);
1794 }
1795 if (ret != LTTNG_OK) {
1796 goto error_unlock;
1797 }
1798 break;
1799 default:
1800 ret = LTTNG_ERR_UNK;
1801 goto error_unlock;
1802 }
1803
1804 kernel_wait_quiescent();
1805 break;
1806 }
1807 case LTTNG_DOMAIN_UST:
1808 {
1809 struct ltt_ust_channel *uchan;
1810 struct ltt_ust_session *usess;
1811
1812 usess = session->ust_session;
1813
1814 if (validate_ust_event_name(event_name)) {
1815 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1816 goto error_unlock;
1817 }
1818
1819 /*
1820 * If a non-default channel has been created in the
1821 * session, explicitly require that -c chan_name needs
1822 * to be provided.
1823 */
1824 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1825 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1826 goto error_unlock;
1827 }
1828
1829 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1830 channel_name);
1831 if (uchan == NULL) {
1832 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1833 goto error_unlock;
1834 }
1835
1836 switch (event->type) {
1837 case LTTNG_EVENT_ALL:
1838 /*
1839 * An empty event name means that everything
1840 * should be disabled.
1841 */
1842 if (event->name[0] == '\0') {
1843 ret = event_ust_disable_all_tracepoints(usess, uchan);
1844 } else {
1845 ret = event_ust_disable_tracepoint(usess, uchan,
1846 event_name);
1847 }
1848 if (ret != LTTNG_OK) {
1849 goto error_unlock;
1850 }
1851 break;
1852 default:
1853 ret = LTTNG_ERR_UNK;
1854 goto error_unlock;
1855 }
1856
1857 DBG3("Disable UST event %s in channel %s completed", event_name,
1858 channel_name);
1859 break;
1860 }
1861 case LTTNG_DOMAIN_LOG4J:
1862 case LTTNG_DOMAIN_JUL:
1863 case LTTNG_DOMAIN_PYTHON:
1864 {
1865 struct agent *agt;
1866 struct ltt_ust_session *usess = session->ust_session;
1867
1868 assert(usess);
1869
1870 switch (event->type) {
1871 case LTTNG_EVENT_ALL:
1872 break;
1873 default:
1874 ret = LTTNG_ERR_UNK;
1875 goto error_unlock;
1876 }
1877
1878 agt = trace_ust_find_agent(usess, domain);
1879 if (!agt) {
1880 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1881 goto error_unlock;
1882 }
1883 /*
1884 * An empty event name means that everything
1885 * should be disabled.
1886 */
1887 if (event->name[0] == '\0') {
1888 ret = event_agent_disable_all(usess, agt);
1889 } else {
1890 ret = event_agent_disable(usess, agt, event_name);
1891 }
1892 if (ret != LTTNG_OK) {
1893 goto error_unlock;
1894 }
1895
1896 break;
1897 }
1898 default:
1899 ret = LTTNG_ERR_UND;
1900 goto error_unlock;
1901 }
1902
1903 ret = LTTNG_OK;
1904
1905 error_unlock:
1906 rcu_read_unlock();
1907 error:
1908 return ret;
1909 }
1910
1911 /*
1912 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1913 */
1914 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1915 char *channel_name, const struct lttng_event_context *ctx, int kwpipe)
1916 {
1917 int ret, chan_kern_created = 0, chan_ust_created = 0;
1918 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1919
1920 /*
1921 * Don't try to add a context if the session has been started at
1922 * some point in time before. The tracer does not allow it and would
1923 * result in a corrupted trace.
1924 */
1925 if (session->has_been_started) {
1926 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1927 goto end;
1928 }
1929
1930 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1931 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1932 app_ctx_name = ctx->u.app_ctx.ctx_name;
1933 }
1934
1935 switch (domain) {
1936 case LTTNG_DOMAIN_KERNEL:
1937 assert(session->kernel_session);
1938
1939 if (session->kernel_session->channel_count == 0) {
1940 /* Create default channel */
1941 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1942 if (ret != LTTNG_OK) {
1943 goto error;
1944 }
1945 chan_kern_created = 1;
1946 }
1947 /* Add kernel context to kernel tracer */
1948 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1949 if (ret != LTTNG_OK) {
1950 goto error;
1951 }
1952 break;
1953 case LTTNG_DOMAIN_JUL:
1954 case LTTNG_DOMAIN_LOG4J:
1955 {
1956 /*
1957 * Validate channel name.
1958 * If no channel name is given and the domain is JUL or LOG4J,
1959 * set it to the appropriate domain-specific channel name. If
1960 * a name is provided but does not match the expexted channel
1961 * name, return an error.
1962 */
1963 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1964 strcmp(channel_name,
1965 DEFAULT_JUL_CHANNEL_NAME)) {
1966 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1967 goto error;
1968 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1969 strcmp(channel_name,
1970 DEFAULT_LOG4J_CHANNEL_NAME)) {
1971 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1972 goto error;
1973 }
1974 /* break is _not_ missing here. */
1975 }
1976 case LTTNG_DOMAIN_UST:
1977 {
1978 struct ltt_ust_session *usess = session->ust_session;
1979 unsigned int chan_count;
1980
1981 assert(usess);
1982
1983 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1984 if (chan_count == 0) {
1985 struct lttng_channel *attr;
1986 /* Create default channel */
1987 attr = channel_new_default_attr(domain, usess->buffer_type);
1988 if (attr == NULL) {
1989 ret = LTTNG_ERR_FATAL;
1990 goto error;
1991 }
1992
1993 ret = channel_ust_create(usess, attr, usess->buffer_type);
1994 if (ret != LTTNG_OK) {
1995 free(attr);
1996 goto error;
1997 }
1998 channel_attr_destroy(attr);
1999 chan_ust_created = 1;
2000 }
2001
2002 ret = context_ust_add(usess, domain, ctx, channel_name);
2003 free(app_ctx_provider_name);
2004 free(app_ctx_name);
2005 app_ctx_name = NULL;
2006 app_ctx_provider_name = NULL;
2007 if (ret != LTTNG_OK) {
2008 goto error;
2009 }
2010 break;
2011 }
2012 default:
2013 ret = LTTNG_ERR_UND;
2014 goto error;
2015 }
2016
2017 ret = LTTNG_OK;
2018 goto end;
2019
2020 error:
2021 if (chan_kern_created) {
2022 struct ltt_kernel_channel *kchan =
2023 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
2024 session->kernel_session);
2025 /* Created previously, this should NOT fail. */
2026 assert(kchan);
2027 kernel_destroy_channel(kchan);
2028 }
2029
2030 if (chan_ust_created) {
2031 struct ltt_ust_channel *uchan =
2032 trace_ust_find_channel_by_name(
2033 session->ust_session->domain_global.channels,
2034 DEFAULT_CHANNEL_NAME);
2035 /* Created previously, this should NOT fail. */
2036 assert(uchan);
2037 /* Remove from the channel list of the session. */
2038 trace_ust_delete_channel(session->ust_session->domain_global.channels,
2039 uchan);
2040 trace_ust_destroy_channel(uchan);
2041 }
2042 end:
2043 free(app_ctx_provider_name);
2044 free(app_ctx_name);
2045 return ret;
2046 }
2047
2048 static inline bool name_starts_with(const char *name, const char *prefix)
2049 {
2050 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
2051
2052 return !strncmp(name, prefix, max_cmp_len);
2053 }
2054
2055 /* Perform userspace-specific event name validation */
2056 static int validate_ust_event_name(const char *name)
2057 {
2058 int ret = 0;
2059
2060 if (!name) {
2061 ret = -1;
2062 goto end;
2063 }
2064
2065 /*
2066 * Check name against all internal UST event component namespaces used
2067 * by the agents.
2068 */
2069 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
2070 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
2071 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
2072 ret = -1;
2073 }
2074
2075 end:
2076 return ret;
2077 }
2078
2079 /*
2080 * Internal version of cmd_enable_event() with a supplemental
2081 * "internal_event" flag which is used to enable internal events which should
2082 * be hidden from clients. Such events are used in the agent implementation to
2083 * enable the events through which all "agent" events are funeled.
2084 */
2085 static int _cmd_enable_event(struct ltt_session *session,
2086 const struct lttng_domain *domain,
2087 char *channel_name, struct lttng_event *event,
2088 char *filter_expression,
2089 struct lttng_bytecode *filter,
2090 struct lttng_event_exclusion *exclusion,
2091 int wpipe, bool internal_event)
2092 {
2093 int ret = 0, channel_created = 0;
2094 struct lttng_channel *attr = NULL;
2095
2096 assert(session);
2097 assert(event);
2098 assert(channel_name);
2099
2100 /* If we have a filter, we must have its filter expression */
2101 assert(!(!!filter_expression ^ !!filter));
2102
2103 /* Normalize event name as a globbing pattern */
2104 strutils_normalize_star_glob_pattern(event->name);
2105
2106 /* Normalize exclusion names as globbing patterns */
2107 if (exclusion) {
2108 size_t i;
2109
2110 for (i = 0; i < exclusion->count; i++) {
2111 char *name = LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
2112
2113 strutils_normalize_star_glob_pattern(name);
2114 }
2115 }
2116
2117 DBG("Enable event command for event \'%s\'", event->name);
2118
2119 rcu_read_lock();
2120
2121 switch (domain->type) {
2122 case LTTNG_DOMAIN_KERNEL:
2123 {
2124 struct ltt_kernel_channel *kchan;
2125
2126 /*
2127 * If a non-default channel has been created in the
2128 * session, explicitely require that -c chan_name needs
2129 * to be provided.
2130 */
2131 if (session->kernel_session->has_non_default_channel
2132 && channel_name[0] == '\0') {
2133 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2134 goto error;
2135 }
2136
2137 kchan = trace_kernel_get_channel_by_name(channel_name,
2138 session->kernel_session);
2139 if (kchan == NULL) {
2140 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
2141 LTTNG_BUFFER_GLOBAL);
2142 if (attr == NULL) {
2143 ret = LTTNG_ERR_FATAL;
2144 goto error;
2145 }
2146 if (lttng_strncpy(attr->name, channel_name,
2147 sizeof(attr->name))) {
2148 ret = LTTNG_ERR_INVALID;
2149 goto error;
2150 }
2151
2152 ret = cmd_enable_channel(session, domain, attr, wpipe);
2153 if (ret != LTTNG_OK) {
2154 goto error;
2155 }
2156 channel_created = 1;
2157 }
2158
2159 /* Get the newly created kernel channel pointer */
2160 kchan = trace_kernel_get_channel_by_name(channel_name,
2161 session->kernel_session);
2162 if (kchan == NULL) {
2163 /* This sould not happen... */
2164 ret = LTTNG_ERR_FATAL;
2165 goto error;
2166 }
2167
2168 switch (event->type) {
2169 case LTTNG_EVENT_ALL:
2170 {
2171 char *filter_expression_a = NULL;
2172 struct lttng_bytecode *filter_a = NULL;
2173
2174 /*
2175 * We need to duplicate filter_expression and filter,
2176 * because ownership is passed to first enable
2177 * event.
2178 */
2179 if (filter_expression) {
2180 filter_expression_a = strdup(filter_expression);
2181 if (!filter_expression_a) {
2182 ret = LTTNG_ERR_FATAL;
2183 goto error;
2184 }
2185 }
2186 if (filter) {
2187 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
2188 if (!filter_a) {
2189 free(filter_expression_a);
2190 ret = LTTNG_ERR_FATAL;
2191 goto error;
2192 }
2193 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
2194 }
2195 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
2196 ret = event_kernel_enable_event(kchan, event,
2197 filter_expression, filter);
2198 /* We have passed ownership */
2199 filter_expression = NULL;
2200 filter = NULL;
2201 if (ret != LTTNG_OK) {
2202 if (channel_created) {
2203 /* Let's not leak a useless channel. */
2204 kernel_destroy_channel(kchan);
2205 }
2206 free(filter_expression_a);
2207 free(filter_a);
2208 goto error;
2209 }
2210 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
2211 ret = event_kernel_enable_event(kchan, event,
2212 filter_expression_a, filter_a);
2213 /* We have passed ownership */
2214 filter_expression_a = NULL;
2215 filter_a = NULL;
2216 if (ret != LTTNG_OK) {
2217 goto error;
2218 }
2219 break;
2220 }
2221 case LTTNG_EVENT_PROBE:
2222 case LTTNG_EVENT_USERSPACE_PROBE:
2223 case LTTNG_EVENT_FUNCTION:
2224 case LTTNG_EVENT_FUNCTION_ENTRY:
2225 case LTTNG_EVENT_TRACEPOINT:
2226 ret = event_kernel_enable_event(kchan, event,
2227 filter_expression, filter);
2228 /* We have passed ownership */
2229 filter_expression = NULL;
2230 filter = NULL;
2231 if (ret != LTTNG_OK) {
2232 if (channel_created) {
2233 /* Let's not leak a useless channel. */
2234 kernel_destroy_channel(kchan);
2235 }
2236 goto error;
2237 }
2238 break;
2239 case LTTNG_EVENT_SYSCALL:
2240 ret = event_kernel_enable_event(kchan, event,
2241 filter_expression, filter);
2242 /* We have passed ownership */
2243 filter_expression = NULL;
2244 filter = NULL;
2245 if (ret != LTTNG_OK) {
2246 goto error;
2247 }
2248 break;
2249 default:
2250 ret = LTTNG_ERR_UNK;
2251 goto error;
2252 }
2253
2254 kernel_wait_quiescent();
2255 break;
2256 }
2257 case LTTNG_DOMAIN_UST:
2258 {
2259 struct ltt_ust_channel *uchan;
2260 struct ltt_ust_session *usess = session->ust_session;
2261
2262 assert(usess);
2263
2264 /*
2265 * If a non-default channel has been created in the
2266 * session, explicitely require that -c chan_name needs
2267 * to be provided.
2268 */
2269 if (usess->has_non_default_channel && channel_name[0] == '\0') {
2270 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2271 goto error;
2272 }
2273
2274 /* Get channel from global UST domain */
2275 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2276 channel_name);
2277 if (uchan == NULL) {
2278 /* Create default channel */
2279 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
2280 usess->buffer_type);
2281 if (attr == NULL) {
2282 ret = LTTNG_ERR_FATAL;
2283 goto error;
2284 }
2285 if (lttng_strncpy(attr->name, channel_name,
2286 sizeof(attr->name))) {
2287 ret = LTTNG_ERR_INVALID;
2288 goto error;
2289 }
2290
2291 ret = cmd_enable_channel(session, domain, attr, wpipe);
2292 if (ret != LTTNG_OK) {
2293 goto error;
2294 }
2295
2296 /* Get the newly created channel reference back */
2297 uchan = trace_ust_find_channel_by_name(
2298 usess->domain_global.channels, channel_name);
2299 assert(uchan);
2300 }
2301
2302 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2303 /*
2304 * Don't allow users to add UST events to channels which
2305 * are assigned to a userspace subdomain (JUL, Log4J,
2306 * Python, etc.).
2307 */
2308 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2309 goto error;
2310 }
2311
2312 if (!internal_event) {
2313 /*
2314 * Ensure the event name is not reserved for internal
2315 * use.
2316 */
2317 ret = validate_ust_event_name(event->name);
2318 if (ret) {
2319 WARN("Userspace event name %s failed validation.",
2320 event->name);
2321 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2322 goto error;
2323 }
2324 }
2325
2326 /* At this point, the session and channel exist on the tracer */
2327 ret = event_ust_enable_tracepoint(usess, uchan, event,
2328 filter_expression, filter, exclusion,
2329 internal_event);
2330 /* We have passed ownership */
2331 filter_expression = NULL;
2332 filter = NULL;
2333 exclusion = NULL;
2334 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2335 goto already_enabled;
2336 } else if (ret != LTTNG_OK) {
2337 goto error;
2338 }
2339 break;
2340 }
2341 case LTTNG_DOMAIN_LOG4J:
2342 case LTTNG_DOMAIN_JUL:
2343 case LTTNG_DOMAIN_PYTHON:
2344 {
2345 const char *default_event_name, *default_chan_name;
2346 struct agent *agt;
2347 struct lttng_event uevent;
2348 struct lttng_domain tmp_dom;
2349 struct ltt_ust_session *usess = session->ust_session;
2350
2351 assert(usess);
2352
2353 if (!agent_tracing_is_enabled()) {
2354 DBG("Attempted to enable an event in an agent domain but the agent thread is not running");
2355 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
2356 goto error;
2357 }
2358
2359 agt = trace_ust_find_agent(usess, domain->type);
2360 if (!agt) {
2361 agt = agent_create(domain->type);
2362 if (!agt) {
2363 ret = LTTNG_ERR_NOMEM;
2364 goto error;
2365 }
2366 agent_add(agt, usess->agents);
2367 }
2368
2369 /* Create the default tracepoint. */
2370 memset(&uevent, 0, sizeof(uevent));
2371 uevent.type = LTTNG_EVENT_TRACEPOINT;
2372 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2373 default_event_name = event_get_default_agent_ust_name(
2374 domain->type);
2375 if (!default_event_name) {
2376 ret = LTTNG_ERR_FATAL;
2377 goto error;
2378 }
2379 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2380 uevent.name[sizeof(uevent.name) - 1] = '\0';
2381
2382 /*
2383 * The domain type is changed because we are about to enable the
2384 * default channel and event for the JUL domain that are hardcoded.
2385 * This happens in the UST domain.
2386 */
2387 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2388 tmp_dom.type = LTTNG_DOMAIN_UST;
2389
2390 switch (domain->type) {
2391 case LTTNG_DOMAIN_LOG4J:
2392 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2393 break;
2394 case LTTNG_DOMAIN_JUL:
2395 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2396 break;
2397 case LTTNG_DOMAIN_PYTHON:
2398 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2399 break;
2400 default:
2401 /* The switch/case we are in makes this impossible */
2402 assert(0);
2403 }
2404
2405 {
2406 char *filter_expression_copy = NULL;
2407 struct lttng_bytecode *filter_copy = NULL;
2408
2409 if (filter) {
2410 const size_t filter_size = sizeof(
2411 struct lttng_bytecode)
2412 + filter->len;
2413
2414 filter_copy = zmalloc(filter_size);
2415 if (!filter_copy) {
2416 ret = LTTNG_ERR_NOMEM;
2417 goto error;
2418 }
2419 memcpy(filter_copy, filter, filter_size);
2420
2421 filter_expression_copy =
2422 strdup(filter_expression);
2423 if (!filter_expression) {
2424 ret = LTTNG_ERR_NOMEM;
2425 }
2426
2427 if (!filter_expression_copy || !filter_copy) {
2428 free(filter_expression_copy);
2429 free(filter_copy);
2430 goto error;
2431 }
2432 }
2433
2434 ret = cmd_enable_event_internal(session, &tmp_dom,
2435 (char *) default_chan_name,
2436 &uevent, filter_expression_copy,
2437 filter_copy, NULL, wpipe);
2438 }
2439
2440 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2441 goto already_enabled;
2442 } else if (ret != LTTNG_OK) {
2443 goto error;
2444 }
2445
2446 /* The wild card * means that everything should be enabled. */
2447 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2448 ret = event_agent_enable_all(usess, agt, event, filter,
2449 filter_expression);
2450 } else {
2451 ret = event_agent_enable(usess, agt, event, filter,
2452 filter_expression);
2453 }
2454 filter = NULL;
2455 filter_expression = NULL;
2456 if (ret != LTTNG_OK) {
2457 goto error;
2458 }
2459
2460 break;
2461 }
2462 default:
2463 ret = LTTNG_ERR_UND;
2464 goto error;
2465 }
2466
2467 ret = LTTNG_OK;
2468
2469 already_enabled:
2470 error:
2471 free(filter_expression);
2472 free(filter);
2473 free(exclusion);
2474 channel_attr_destroy(attr);
2475 rcu_read_unlock();
2476 return ret;
2477 }
2478
2479 /*
2480 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2481 * We own filter, exclusion, and filter_expression.
2482 */
2483 int cmd_enable_event(struct ltt_session *session,
2484 const struct lttng_domain *domain,
2485 char *channel_name, struct lttng_event *event,
2486 char *filter_expression,
2487 struct lttng_bytecode *filter,
2488 struct lttng_event_exclusion *exclusion,
2489 int wpipe)
2490 {
2491 return _cmd_enable_event(session, domain, channel_name, event,
2492 filter_expression, filter, exclusion, wpipe, false);
2493 }
2494
2495 /*
2496 * Enable an event which is internal to LTTng. An internal should
2497 * never be made visible to clients and are immune to checks such as
2498 * reserved names.
2499 */
2500 static int cmd_enable_event_internal(struct ltt_session *session,
2501 const struct lttng_domain *domain,
2502 char *channel_name, struct lttng_event *event,
2503 char *filter_expression,
2504 struct lttng_bytecode *filter,
2505 struct lttng_event_exclusion *exclusion,
2506 int wpipe)
2507 {
2508 return _cmd_enable_event(session, domain, channel_name, event,
2509 filter_expression, filter, exclusion, wpipe, true);
2510 }
2511
2512 /*
2513 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2514 */
2515 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2516 struct lttng_event **events)
2517 {
2518 int ret;
2519 ssize_t nb_events = 0;
2520
2521 switch (domain) {
2522 case LTTNG_DOMAIN_KERNEL:
2523 nb_events = kernel_list_events(events);
2524 if (nb_events < 0) {
2525 ret = LTTNG_ERR_KERN_LIST_FAIL;
2526 goto error;
2527 }
2528 break;
2529 case LTTNG_DOMAIN_UST:
2530 nb_events = ust_app_list_events(events);
2531 if (nb_events < 0) {
2532 ret = LTTNG_ERR_UST_LIST_FAIL;
2533 goto error;
2534 }
2535 break;
2536 case LTTNG_DOMAIN_LOG4J:
2537 case LTTNG_DOMAIN_JUL:
2538 case LTTNG_DOMAIN_PYTHON:
2539 nb_events = agent_list_events(events, domain);
2540 if (nb_events < 0) {
2541 ret = LTTNG_ERR_UST_LIST_FAIL;
2542 goto error;
2543 }
2544 break;
2545 default:
2546 ret = LTTNG_ERR_UND;
2547 goto error;
2548 }
2549
2550 return nb_events;
2551
2552 error:
2553 /* Return negative value to differentiate return code */
2554 return -ret;
2555 }
2556
2557 /*
2558 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2559 */
2560 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2561 struct lttng_event_field **fields)
2562 {
2563 int ret;
2564 ssize_t nb_fields = 0;
2565
2566 switch (domain) {
2567 case LTTNG_DOMAIN_UST:
2568 nb_fields = ust_app_list_event_fields(fields);
2569 if (nb_fields < 0) {
2570 ret = LTTNG_ERR_UST_LIST_FAIL;
2571 goto error;
2572 }
2573 break;
2574 case LTTNG_DOMAIN_KERNEL:
2575 default: /* fall-through */
2576 ret = LTTNG_ERR_UND;
2577 goto error;
2578 }
2579
2580 return nb_fields;
2581
2582 error:
2583 /* Return negative value to differentiate return code */
2584 return -ret;
2585 }
2586
2587 ssize_t cmd_list_syscalls(struct lttng_event **events)
2588 {
2589 return syscall_table_list(events);
2590 }
2591
2592 /*
2593 * Command LTTNG_START_TRACE processed by the client thread.
2594 *
2595 * Called with session mutex held.
2596 */
2597 int cmd_start_trace(struct ltt_session *session)
2598 {
2599 enum lttng_error_code ret;
2600 unsigned long nb_chan = 0;
2601 struct ltt_kernel_session *ksession;
2602 struct ltt_ust_session *usess;
2603 const bool session_rotated_after_last_stop =
2604 session->rotated_after_last_stop;
2605 const bool session_cleared_after_last_stop =
2606 session->cleared_after_last_stop;
2607
2608 assert(session);
2609
2610 /* Ease our life a bit ;) */
2611 ksession = session->kernel_session;
2612 usess = session->ust_session;
2613
2614 /* Is the session already started? */
2615 if (session->active) {
2616 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2617 /* Perform nothing */
2618 goto end;
2619 }
2620
2621 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING &&
2622 !session->current_trace_chunk) {
2623 /*
2624 * A rotation was launched while the session was stopped and
2625 * it has not been completed yet. It is not possible to start
2626 * the session since starting the session here would require a
2627 * rotation from "NULL" to a new trace chunk. That rotation
2628 * would overlap with the ongoing rotation, which is not
2629 * supported.
2630 */
2631 WARN("Refusing to start session \"%s\" as a rotation launched after the last \"stop\" is still ongoing",
2632 session->name);
2633 ret = LTTNG_ERR_ROTATION_PENDING;
2634 goto error;
2635 }
2636
2637 /*
2638 * Starting a session without channel is useless since after that it's not
2639 * possible to enable channel thus inform the client.
2640 */
2641 if (usess && usess->domain_global.channels) {
2642 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2643 }
2644 if (ksession) {
2645 nb_chan += ksession->channel_count;
2646 }
2647 if (!nb_chan) {
2648 ret = LTTNG_ERR_NO_CHANNEL;
2649 goto error;
2650 }
2651
2652 session->active = 1;
2653 session->rotated_after_last_stop = false;
2654 session->cleared_after_last_stop = false;
2655 if (session->output_traces && !session->current_trace_chunk) {
2656 if (!session->has_been_started) {
2657 struct lttng_trace_chunk *trace_chunk;
2658
2659 DBG("Creating initial trace chunk of session \"%s\"",
2660 session->name);
2661 trace_chunk = session_create_new_trace_chunk(
2662 session, NULL, NULL, NULL);
2663 if (!trace_chunk) {
2664 ret = LTTNG_ERR_CREATE_DIR_FAIL;
2665 goto error;
2666 }
2667 assert(!session->current_trace_chunk);
2668 ret = session_set_trace_chunk(session, trace_chunk,
2669 NULL);
2670 lttng_trace_chunk_put(trace_chunk);
2671 if (ret) {
2672 ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
2673 goto error;
2674 }
2675 } else {
2676 DBG("Rotating session \"%s\" from its current \"NULL\" trace chunk to a new chunk",
2677 session->name);
2678 /*
2679 * Rotate existing streams into the new chunk.
2680 * This is a "quiet" rotation has no client has
2681 * explicitly requested this operation.
2682 *
2683 * There is also no need to wait for the rotation
2684 * to complete as it will happen immediately. No data
2685 * was produced as the session was stopped, so the
2686 * rotation should happen on reception of the command.
2687 */
2688 ret = cmd_rotate_session(session, NULL, true,
2689 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
2690 if (ret != LTTNG_OK) {
2691 goto error;
2692 }
2693 }
2694 }
2695
2696 /* Kernel tracing */
2697 if (ksession != NULL) {
2698 DBG("Start kernel tracing session %s", session->name);
2699 ret = start_kernel_session(ksession);
2700 if (ret != LTTNG_OK) {
2701 goto error;
2702 }
2703 }
2704
2705 /* Flag session that trace should start automatically */
2706 if (usess) {
2707 int int_ret = ust_app_start_trace_all(usess);
2708
2709 if (int_ret < 0) {
2710 ret = LTTNG_ERR_UST_START_FAIL;
2711 goto error;
2712 }
2713 }
2714
2715 /*
2716 * Open a packet in every stream of the session to ensure that viewers
2717 * can correctly identify the boundaries of the periods during which
2718 * tracing was active for this session.
2719 */
2720 ret = session_open_packets(session);
2721 if (ret != LTTNG_OK) {
2722 goto error;
2723 }
2724
2725 /*
2726 * Clear the flag that indicates that a rotation was done while the
2727 * session was stopped.
2728 */
2729 session->rotated_after_last_stop = false;
2730
2731 if (session->rotate_timer_period) {
2732 int int_ret = timer_session_rotation_schedule_timer_start(
2733 session, session->rotate_timer_period);
2734
2735 if (int_ret < 0) {
2736 ERR("Failed to enable rotate timer");
2737 ret = LTTNG_ERR_UNK;
2738 goto error;
2739 }
2740 }
2741
2742 ret = LTTNG_OK;
2743
2744 error:
2745 if (ret == LTTNG_OK) {
2746 /* Flag this after a successful start. */
2747 session->has_been_started |= 1;
2748 } else {
2749 session->active = 0;
2750 /* Restore initial state on error. */
2751 session->rotated_after_last_stop =
2752 session_rotated_after_last_stop;
2753 session->cleared_after_last_stop =
2754 session_cleared_after_last_stop;
2755 }
2756 end:
2757 return ret;
2758 }
2759
2760 /*
2761 * Command LTTNG_STOP_TRACE processed by the client thread.
2762 */
2763 int cmd_stop_trace(struct ltt_session *session)
2764 {
2765 int ret;
2766 struct ltt_kernel_session *ksession;
2767 struct ltt_ust_session *usess;
2768
2769 assert(session);
2770
2771 DBG("Begin stop session \"%s\" (id %" PRIu64 ")", session->name, session->id);
2772 /* Short cut */
2773 ksession = session->kernel_session;
2774 usess = session->ust_session;
2775
2776 /* Session is not active. Skip everythong and inform the client. */
2777 if (!session->active) {
2778 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2779 goto error;
2780 }
2781
2782 ret = stop_kernel_session(ksession);
2783 if (ret != LTTNG_OK) {
2784 goto error;
2785 }
2786
2787 if (usess && usess->active) {
2788 ret = ust_app_stop_trace_all(usess);
2789 if (ret < 0) {
2790 ret = LTTNG_ERR_UST_STOP_FAIL;
2791 goto error;
2792 }
2793 }
2794
2795 DBG("Completed stop session \"%s\" (id %" PRIu64 ")", session->name,
2796 session->id);
2797 /* Flag inactive after a successful stop. */
2798 session->active = 0;
2799 ret = LTTNG_OK;
2800
2801 error:
2802 return ret;
2803 }
2804
2805 /*
2806 * Set the base_path of the session only if subdir of a control uris is set.
2807 * Return LTTNG_OK on success, otherwise LTTNG_ERR_*.
2808 */
2809 static int set_session_base_path_from_uris(struct ltt_session *session,
2810 size_t nb_uri,
2811 struct lttng_uri *uris)
2812 {
2813 int ret;
2814 size_t i;
2815
2816 for (i = 0; i < nb_uri; i++) {
2817 if (uris[i].stype != LTTNG_STREAM_CONTROL ||
2818 uris[i].subdir[0] == '\0') {
2819 /* Not interested in these URIs */
2820 continue;
2821 }
2822
2823 if (session->base_path != NULL) {
2824 free(session->base_path);
2825 session->base_path = NULL;
2826 }
2827
2828 /* Set session base_path */
2829 session->base_path = strdup(uris[i].subdir);
2830 if (!session->base_path) {
2831 PERROR("Failed to copy base path \"%s\" to session \"%s\"",
2832 uris[i].subdir, session->name);
2833 ret = LTTNG_ERR_NOMEM;
2834 goto error;
2835 }
2836 DBG2("Setting base path \"%s\" for session \"%s\"",
2837 session->base_path, session->name);
2838 }
2839 ret = LTTNG_OK;
2840 error:
2841 return ret;
2842 }
2843
2844 /*
2845 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2846 */
2847 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2848 struct lttng_uri *uris)
2849 {
2850 int ret, i;
2851 struct ltt_kernel_session *ksess = session->kernel_session;
2852 struct ltt_ust_session *usess = session->ust_session;
2853
2854 assert(session);
2855 assert(uris);
2856 assert(nb_uri > 0);
2857
2858 /* Can't set consumer URI if the session is active. */
2859 if (session->active) {
2860 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2861 goto error;
2862 }
2863
2864 /*
2865 * Set the session base path if any. This is done inside
2866 * cmd_set_consumer_uri to preserve backward compatibility of the
2867 * previous session creation api vs the session descriptor api.
2868 */
2869 ret = set_session_base_path_from_uris(session, nb_uri, uris);
2870 if (ret != LTTNG_OK) {
2871 goto error;
2872 }
2873
2874 /* Set the "global" consumer URIs */
2875 for (i = 0; i < nb_uri; i++) {
2876 ret = add_uri_to_consumer(session, session->consumer, &uris[i],
2877 LTTNG_DOMAIN_NONE);
2878 if (ret != LTTNG_OK) {
2879 goto error;
2880 }
2881 }
2882
2883 /* Set UST session URIs */
2884 if (session->ust_session) {
2885 for (i = 0; i < nb_uri; i++) {
2886 ret = add_uri_to_consumer(session,
2887 session->ust_session->consumer,
2888 &uris[i], LTTNG_DOMAIN_UST);
2889 if (ret != LTTNG_OK) {
2890 goto error;
2891 }
2892 }
2893 }
2894
2895 /* Set kernel session URIs */
2896 if (session->kernel_session) {
2897 for (i = 0; i < nb_uri; i++) {
2898 ret = add_uri_to_consumer(session,
2899 session->kernel_session->consumer,
2900 &uris[i], LTTNG_DOMAIN_KERNEL);
2901 if (ret != LTTNG_OK) {
2902 goto error;
2903 }
2904 }
2905 }
2906
2907 /*
2908 * Make sure to set the session in output mode after we set URI since a
2909 * session can be created without URL (thus flagged in no output mode).
2910 */
2911 session->output_traces = 1;
2912 if (ksess) {
2913 ksess->output_traces = 1;
2914 }
2915
2916 if (usess) {
2917 usess->output_traces = 1;
2918 }
2919
2920 /* All good! */
2921 ret = LTTNG_OK;
2922
2923 error:
2924 return ret;
2925 }
2926
2927 static
2928 enum lttng_error_code set_session_output_from_descriptor(
2929 struct ltt_session *session,
2930 const struct lttng_session_descriptor *descriptor)
2931 {
2932 int ret;
2933 enum lttng_error_code ret_code = LTTNG_OK;
2934 enum lttng_session_descriptor_type session_type =
2935 lttng_session_descriptor_get_type(descriptor);
2936 enum lttng_session_descriptor_output_type output_type =
2937 lttng_session_descriptor_get_output_type(descriptor);
2938 struct lttng_uri uris[2] = {};
2939 size_t uri_count = 0;
2940
2941 switch (output_type) {
2942 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NONE:
2943 goto end;
2944 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_LOCAL:
2945 lttng_session_descriptor_get_local_output_uri(descriptor,
2946 &uris[0]);
2947 uri_count = 1;
2948 break;
2949 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NETWORK:
2950 lttng_session_descriptor_get_network_output_uris(descriptor,
2951 &uris[0], &uris[1]);
2952 uri_count = 2;
2953 break;
2954 default:
2955 ret_code = LTTNG_ERR_INVALID;
2956 goto end;
2957 }
2958
2959 switch (session_type) {
2960 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
2961 {
2962 struct snapshot_output *new_output = NULL;
2963
2964 new_output = snapshot_output_alloc();
2965 if (!new_output) {
2966 ret_code = LTTNG_ERR_NOMEM;
2967 goto end;
2968 }
2969
2970 ret = snapshot_output_init_with_uri(session,
2971 DEFAULT_SNAPSHOT_MAX_SIZE,
2972 NULL, uris, uri_count, session->consumer,
2973 new_output, &session->snapshot);
2974 if (ret < 0) {
2975 ret_code = (ret == -ENOMEM) ?
2976 LTTNG_ERR_NOMEM : LTTNG_ERR_INVALID;
2977 snapshot_output_destroy(new_output);
2978 goto end;
2979 }
2980 snapshot_add_output(&session->snapshot, new_output);
2981 break;
2982 }
2983 case LTTNG_SESSION_DESCRIPTOR_TYPE_REGULAR:
2984 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
2985 {
2986 ret_code = cmd_set_consumer_uri(session, uri_count, uris);
2987 break;
2988 }
2989 default:
2990 ret_code = LTTNG_ERR_INVALID;
2991 goto end;
2992 }
2993 end:
2994 return ret_code;
2995 }
2996
2997 static
2998 enum lttng_error_code cmd_create_session_from_descriptor(
2999 struct lttng_session_descriptor *descriptor,
3000 const lttng_sock_cred *creds,
3001 const char *home_path)
3002 {
3003 int ret;
3004 enum lttng_error_code ret_code;
3005 const char *session_name;
3006 struct ltt_session *new_session = NULL;
3007 enum lttng_session_descriptor_status descriptor_status;
3008
3009 session_lock_list();
3010 if (home_path) {
3011 if (*home_path != '/') {
3012 ERR("Home path provided by client is not absolute");
3013 ret_code = LTTNG_ERR_INVALID;
3014 goto end;
3015 }
3016 }
3017
3018 descriptor_status = lttng_session_descriptor_get_session_name(
3019 descriptor, &session_name);
3020 switch (descriptor_status) {
3021 case LTTNG_SESSION_DESCRIPTOR_STATUS_OK:
3022 break;
3023 case LTTNG_SESSION_DESCRIPTOR_STATUS_UNSET:
3024 session_name = NULL;
3025 break;
3026 default:
3027 ret_code = LTTNG_ERR_INVALID;
3028 goto end;
3029 }
3030
3031 ret_code = session_create(session_name, creds->uid, creds->gid,
3032 &new_session);
3033 if (ret_code != LTTNG_OK) {
3034 goto end;
3035 }
3036
3037 if (!session_name) {
3038 ret = lttng_session_descriptor_set_session_name(descriptor,
3039 new_session->name);
3040 if (ret) {
3041 ret_code = LTTNG_ERR_SESSION_FAIL;
3042 goto end;
3043 }
3044 }
3045
3046 if (!lttng_session_descriptor_is_output_destination_initialized(
3047 descriptor)) {
3048 /*
3049 * Only include the session's creation time in the output
3050 * destination if the name of the session itself was
3051 * not auto-generated.
3052 */
3053 ret_code = lttng_session_descriptor_set_default_output(
3054 descriptor,
3055 session_name ? &new_session->creation_time : NULL,
3056 home_path);
3057 if (ret_code != LTTNG_OK) {
3058 goto end;
3059 }
3060 } else {
3061 new_session->has_user_specified_directory =
3062 lttng_session_descriptor_has_output_directory(
3063 descriptor);
3064 }
3065
3066 switch (lttng_session_descriptor_get_type(descriptor)) {
3067 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
3068 new_session->snapshot_mode = 1;
3069 break;
3070 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3071 new_session->live_timer =
3072 lttng_session_descriptor_live_get_timer_interval(
3073 descriptor);
3074 break;
3075 default:
3076 break;
3077 }
3078
3079 ret_code = set_session_output_from_descriptor(new_session, descriptor);
3080 if (ret_code != LTTNG_OK) {
3081 goto end;
3082 }
3083 new_session->consumer->enabled = 1;
3084 ret_code = LTTNG_OK;
3085 end:
3086 /* Release reference provided by the session_create function. */
3087 session_put(new_session);
3088 if (ret_code != LTTNG_OK && new_session) {
3089 /* Release the global reference on error. */
3090 session_destroy(new_session);
3091 }
3092 session_unlock_list();
3093 return ret_code;
3094 }
3095
3096 enum lttng_error_code cmd_create_session(struct command_ctx *cmd_ctx, int sock,
3097 struct lttng_session_descriptor **return_descriptor)
3098 {
3099 int ret;
3100 size_t payload_size;
3101 struct lttng_dynamic_buffer payload;
3102 struct lttng_buffer_view home_dir_view;
3103 struct lttng_buffer_view session_descriptor_view;
3104 struct lttng_session_descriptor *session_descriptor = NULL;
3105 enum lttng_error_code ret_code;
3106
3107 lttng_dynamic_buffer_init(&payload);
3108 if (cmd_ctx->lsm.u.create_session.home_dir_size >=
3109 LTTNG_PATH_MAX) {
3110 ret_code = LTTNG_ERR_INVALID;
3111 goto error;
3112 }
3113 if (cmd_ctx->lsm.u.create_session.session_descriptor_size >
3114 LTTNG_SESSION_DESCRIPTOR_MAX_LEN) {
3115 ret_code = LTTNG_ERR_INVALID;
3116 goto error;
3117 }
3118
3119 payload_size = cmd_ctx->lsm.u.create_session.home_dir_size +
3120 cmd_ctx->lsm.u.create_session.session_descriptor_size;
3121 ret = lttng_dynamic_buffer_set_size(&payload, payload_size);
3122 if (ret) {
3123 ret_code = LTTNG_ERR_NOMEM;
3124 goto error;
3125 }
3126
3127 ret = lttcomm_recv_unix_sock(sock, payload.data, payload.size);
3128 if (ret <= 0) {
3129 ERR("Reception of session descriptor failed, aborting.");
3130 ret_code = LTTNG_ERR_SESSION_FAIL;
3131 goto error;
3132 }
3133
3134 home_dir_view = lttng_buffer_view_from_dynamic_buffer(
3135 &payload,
3136 0,
3137 cmd_ctx->lsm.u.create_session.home_dir_size);
3138 if (cmd_ctx->lsm.u.create_session.home_dir_size > 0 &&
3139 !lttng_buffer_view_is_valid(&home_dir_view)) {
3140 ERR("Invalid payload in \"create session\" command: buffer too short to contain home directory");
3141 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
3142 goto error;
3143 }
3144
3145 session_descriptor_view = lttng_buffer_view_from_dynamic_buffer(
3146 &payload,
3147 cmd_ctx->lsm.u.create_session.home_dir_size,
3148 cmd_ctx->lsm.u.create_session.session_descriptor_size);
3149 if (!lttng_buffer_view_is_valid(&session_descriptor_view)) {
3150 ERR("Invalid payload in \"create session\" command: buffer too short to contain session descriptor");
3151 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
3152 goto error;
3153 }
3154
3155 ret = lttng_session_descriptor_create_from_buffer(
3156 &session_descriptor_view, &session_descriptor);
3157 if (ret < 0) {
3158 ERR("Failed to create session descriptor from payload of \"create session\" command");
3159 ret_code = LTTNG_ERR_INVALID;
3160 goto error;
3161 }
3162
3163 /*
3164 * Sets the descriptor's auto-generated properties (name, output) if
3165 * needed.
3166 */
3167 ret_code = cmd_create_session_from_descriptor(session_descriptor,
3168 &cmd_ctx->creds,
3169 home_dir_view.size ? home_dir_view.data : NULL);
3170 if (ret_code != LTTNG_OK) {
3171 goto error;
3172 }
3173
3174 ret_code = LTTNG_OK;
3175 *return_descriptor = session_descriptor;
3176 session_descriptor = NULL;
3177 error:
3178 lttng_dynamic_buffer_reset(&payload);
3179 lttng_session_descriptor_destroy(session_descriptor);
3180 return ret_code;
3181 }
3182
3183 static
3184 void cmd_destroy_session_reply(const struct ltt_session *session,
3185 void *_reply_context)
3186 {
3187 int ret;
3188 ssize_t comm_ret;
3189 const struct cmd_destroy_session_reply_context *reply_context =
3190 _reply_context;
3191 struct lttng_dynamic_buffer payload;
3192 struct lttcomm_session_destroy_command_header cmd_header;
3193 struct lttng_trace_archive_location *location = NULL;
3194 struct lttcomm_lttng_msg llm = {
3195 .cmd_type = LTTNG_DESTROY_SESSION,
3196 .ret_code = reply_context->destruction_status,
3197 .pid = UINT32_MAX,
3198 .cmd_header_size =
3199 sizeof(struct lttcomm_session_destroy_command_header),
3200 .data_size = 0,
3201 };
3202 size_t payload_size_before_location;
3203
3204 lttng_dynamic_buffer_init(&payload);
3205
3206 ret = lttng_dynamic_buffer_append(&payload, &llm, sizeof(llm));
3207 if (ret) {
3208 ERR("Failed to append session destruction message");
3209 goto error;
3210 }
3211
3212 cmd_header.rotation_state =
3213 (int32_t) (reply_context->implicit_rotation_on_destroy ?
3214 session->rotation_state :
3215 LTTNG_ROTATION_STATE_NO_ROTATION);
3216 ret = lttng_dynamic_buffer_append(&payload, &cmd_header,
3217 sizeof(cmd_header));
3218 if (ret) {
3219 ERR("Failed to append session destruction command header");
3220 goto error;
3221 }
3222
3223 if (!reply_context->implicit_rotation_on_destroy) {
3224 DBG("No implicit rotation performed during the destruction of session \"%s\", sending reply",
3225 session->name);
3226 goto send_reply;
3227 }
3228 if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED) {
3229 DBG("Rotation state of session \"%s\" is not \"completed\", sending session destruction reply",
3230 session->name);
3231 goto send_reply;
3232 }
3233
3234 location = session_get_trace_archive_location(session);
3235 if (!location) {
3236 ERR("Failed to get the location of the trace archive produced during the destruction of session \"%s\"",
3237 session->name);
3238 goto error;
3239 }
3240
3241 payload_size_before_location = payload.size;
3242 comm_ret = lttng_trace_archive_location_serialize(location,
3243 &payload);
3244 if (comm_ret < 0) {
3245 ERR("Failed to serialize the location of the trace archive produced during the destruction of session \"%s\"",
3246 session->name);
3247 goto error;
3248 }
3249 /* Update the message to indicate the location's length. */
3250 ((struct lttcomm_lttng_msg *) payload.data)->data_size =
3251 payload.size - payload_size_before_location;
3252 send_reply:
3253 comm_ret = lttcomm_send_unix_sock(reply_context->reply_sock_fd,
3254 payload.data, payload.size);
3255 if (comm_ret != (ssize_t) payload.size) {
3256 ERR("Failed to send result of the destruction of session \"%s\" to client",
3257 session->name);
3258 }
3259 error:
3260 ret = close(reply_context->reply_sock_fd);
3261 if (ret) {
3262 PERROR("Failed to close client socket in deferred session destroy reply");
3263 }
3264 lttng_dynamic_buffer_reset(&payload);
3265 free(_reply_context);
3266 }
3267
3268 /*
3269 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3270 *
3271 * Called with session lock held.
3272 */
3273 int cmd_destroy_session(struct ltt_session *session,
3274 struct notification_thread_handle *notification_thread_handle,
3275 int *sock_fd)
3276 {
3277 int ret;
3278 enum lttng_error_code destruction_last_error = LTTNG_OK;
3279 struct cmd_destroy_session_reply_context *reply_context = NULL;
3280
3281 if (sock_fd) {
3282 reply_context = zmalloc(sizeof(*reply_context));
3283 if (!reply_context) {
3284 ret = LTTNG_ERR_NOMEM;
3285 goto end;
3286 }
3287 reply_context->reply_sock_fd = *sock_fd;
3288 }
3289
3290 /* Safety net */
3291 assert(session);
3292
3293 DBG("Begin destroy session %s (id %" PRIu64 ")", session->name,
3294 session->id);
3295 if (session->active) {
3296 DBG("Session \"%s\" is active, attempting to stop it before destroying it",
3297 session->name);
3298 ret = cmd_stop_trace(session);
3299 if (ret != LTTNG_OK && ret != LTTNG_ERR_TRACE_ALREADY_STOPPED) {
3300 /* Carry on with the destruction of the session. */
3301 ERR("Failed to stop session \"%s\" as part of its destruction: %s",
3302 session->name, lttng_strerror(-ret));
3303 destruction_last_error = ret;
3304 }
3305 }
3306
3307 if (session->rotation_schedule_timer_enabled) {
3308 if (timer_session_rotation_schedule_timer_stop(
3309 session)) {
3310 ERR("Failed to stop the \"rotation schedule\" timer of session %s",
3311 session->name);
3312 destruction_last_error = LTTNG_ERR_TIMER_STOP_ERROR;
3313 }
3314 }
3315
3316 if (session->rotate_size) {
3317 unsubscribe_session_consumed_size_rotation(session, notification_thread_handle);
3318 session->rotate_size = 0;
3319 }
3320
3321 if (session->rotated && session->current_trace_chunk && session->output_traces) {
3322 /*
3323 * Perform a last rotation on destruction if rotations have
3324 * occurred during the session's lifetime.
3325 */
3326 ret = cmd_rotate_session(session, NULL, false,
3327 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
3328 if (ret != LTTNG_OK) {
3329 ERR("Failed to perform an implicit rotation as part of the destruction of session \"%s\": %s",
3330 session->name, lttng_strerror(-ret));
3331 destruction_last_error = -ret;
3332 }
3333 if (reply_context) {
3334 reply_context->implicit_rotation_on_destroy = true;
3335 }
3336 } else if (session->has_been_started && session->current_trace_chunk) {
3337 /*
3338 * The user has not triggered a session rotation. However, to
3339 * ensure all data has been consumed, the session is rotated
3340 * to a 'null' trace chunk before it is destroyed.
3341 *
3342 * This is a "quiet" rotation meaning that no notification is
3343 * emitted and no renaming of the current trace chunk takes
3344 * place.
3345 */
3346 ret = cmd_rotate_session(session, NULL, true,
3347 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
3348 /*
3349 * Rotation operations may not be supported by the kernel
3350 * tracer. Hence, do not consider this implicit rotation as
3351 * a session destruction error. The library has already stopped
3352 * the session and waited for pending data; there is nothing
3353 * left to do but complete the destruction of the session.
3354 */
3355 if (ret != LTTNG_OK &&
3356 ret != -LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL) {
3357 ERR("Failed to perform a quiet rotation as part of the destruction of session \"%s\": %s",
3358 session->name, lttng_strerror(ret));
3359 destruction_last_error = -ret;
3360 }
3361 }
3362
3363 if (session->shm_path[0]) {
3364 /*
3365 * When a session is created with an explicit shm_path,
3366 * the consumer daemon will create its shared memory files
3367 * at that location and will *not* unlink them. This is normal
3368 * as the intention of that feature is to make it possible
3369 * to retrieve the content of those files should a crash occur.
3370 *
3371 * To ensure the content of those files can be used, the
3372 * sessiond daemon will replicate the content of the metadata
3373 * cache in a metadata file.
3374 *
3375 * On clean-up, it is expected that the consumer daemon will
3376 * unlink the shared memory files and that the session daemon
3377 * will unlink the metadata file. Then, the session's directory
3378 * in the shm path can be removed.
3379 *
3380 * Unfortunately, a flaw in the design of the sessiond's and
3381 * consumerd's tear down of channels makes it impossible to
3382 * determine when the sessiond _and_ the consumerd have both
3383 * destroyed their representation of a channel. For one, the
3384 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3385 * callbacks in both daemons.
3386 *
3387 * However, it is also impossible for the sessiond to know when
3388 * the consumer daemon is done destroying its channel(s) since
3389 * it occurs as a reaction to the closing of the channel's file
3390 * descriptor. There is no resulting communication initiated
3391 * from the consumerd to the sessiond to confirm that the
3392 * operation is completed (and was successful).
3393 *
3394 * Until this is all fixed, the session daemon checks for the
3395 * removal of the session's shm path which makes it possible
3396 * to safely advertise a session as having been destroyed.
3397 *
3398 * Prior to this fix, it was not possible to reliably save
3399 * a session making use of the --shm-path option, destroy it,
3400 * and load it again. This is because the creation of the
3401 * session would fail upon seeing the session's shm path
3402 * already in existence.
3403 *
3404 * Note that none of the error paths in the check for the
3405 * directory's existence return an error. This is normal
3406 * as there isn't much that can be done. The session will
3407 * be destroyed properly, except that we can't offer the
3408 * guarantee that the same session can be re-created.
3409 */
3410 current_completion_handler = &destroy_completion_handler.handler;
3411 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3412 session->shm_path,
3413 sizeof(destroy_completion_handler.shm_path));
3414 assert(!ret);
3415 }
3416
3417 /*
3418 * The session is destroyed. However, note that the command context
3419 * still holds a reference to the session, thus delaying its destruction
3420 * _at least_ up to the point when that reference is released.
3421 */
3422 session_destroy(session);
3423 if (reply_context) {
3424 reply_context->destruction_status = destruction_last_error;
3425 ret = session_add_destroy_notifier(session,
3426 cmd_destroy_session_reply,
3427 (void *) reply_context);
3428 if (ret) {
3429 ret = LTTNG_ERR_FATAL;
3430 goto end;
3431 } else {
3432 *sock_fd = -1;
3433 }
3434 }
3435 ret = LTTNG_OK;
3436 end:
3437 return ret;
3438 }
3439
3440 /*
3441 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3442 */
3443 int cmd_register_consumer(struct ltt_session *session,
3444 enum lttng_domain_type domain, const char *sock_path,
3445 struct consumer_data *cdata)
3446 {
3447 int ret, sock;
3448 struct consumer_socket *socket = NULL;
3449
3450 assert(session);
3451 assert(cdata);
3452 assert(sock_path);
3453
3454 switch (domain) {
3455 case LTTNG_DOMAIN_KERNEL:
3456 {
3457 struct ltt_kernel_session *ksess = session->kernel_session;
3458
3459 assert(ksess);
3460
3461 /* Can't register a consumer if there is already one */
3462 if (ksess->consumer_fds_sent != 0) {
3463 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3464 goto error;
3465 }
3466
3467 sock = lttcomm_connect_unix_sock(sock_path);
3468 if (sock < 0) {
3469 ret = LTTNG_ERR_CONNECT_FAIL;
3470 goto error;
3471 }
3472 cdata->cmd_sock = sock;
3473
3474 socket = consumer_allocate_socket(&cdata->cmd_sock);
3475 if (socket == NULL) {
3476 ret = close(sock);
3477 if (ret < 0) {
3478 PERROR("close register consumer");
3479 }
3480 cdata->cmd_sock = -1;
3481 ret = LTTNG_ERR_FATAL;
3482 goto error;
3483 }
3484
3485 socket->lock = zmalloc(sizeof(pthread_mutex_t));
3486 if (socket->lock == NULL) {
3487 PERROR("zmalloc pthread mutex");
3488 ret = LTTNG_ERR_FATAL;
3489 goto error;
3490 }
3491 pthread_mutex_init(socket->lock, NULL);
3492 socket->registered = 1;
3493
3494 rcu_read_lock();
3495 consumer_add_socket(socket, ksess->consumer);
3496 rcu_read_unlock();
3497
3498 pthread_mutex_lock(&cdata->pid_mutex);
3499 cdata->pid = -1;
3500 pthread_mutex_unlock(&cdata->pid_mutex);
3501
3502 break;
3503 }
3504 default:
3505 /* TODO: Userspace tracing */
3506 ret = LTTNG_ERR_UND;
3507 goto error;
3508 }
3509
3510 return LTTNG_OK;
3511
3512 error:
3513 if (socket) {
3514 consumer_destroy_socket(socket);
3515 }
3516 return ret;
3517 }
3518
3519 /*
3520 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3521 */
3522 ssize_t cmd_list_domains(struct ltt_session *session,
3523 struct lttng_domain **domains)
3524 {
3525 int ret, index = 0;
3526 ssize_t nb_dom = 0;
3527 struct agent *agt;
3528 struct lttng_ht_iter iter;
3529
3530 if (session->kernel_session != NULL) {
3531 DBG3("Listing domains found kernel domain");
3532 nb_dom++;
3533 }
3534
3535 if (session->ust_session != NULL) {
3536 DBG3("Listing domains found UST global domain");
3537 nb_dom++;
3538
3539 rcu_read_lock();
3540 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3541 agt, node.node) {
3542 if (agt->being_used) {
3543 nb_dom++;
3544 }
3545 }
3546 rcu_read_unlock();
3547 }
3548
3549 if (!nb_dom) {
3550 goto end;
3551 }
3552
3553 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3554 if (*domains == NULL) {
3555 ret = LTTNG_ERR_FATAL;
3556 goto error;
3557 }
3558
3559 if (session->kernel_session != NULL) {
3560 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3561
3562 /* Kernel session buffer type is always GLOBAL */
3563 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3564
3565 index++;
3566 }
3567
3568 if (session->ust_session != NULL) {
3569 (*domains)[index].type = LTTNG_DOMAIN_UST;
3570 (*domains)[index].buf_type = session->ust_session->buffer_type;
3571 index++;
3572
3573 rcu_read_lock();
3574 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3575 agt, node.node) {
3576 if (agt->being_used) {
3577 (*domains)[index].type = agt->domain;
3578 (*domains)[index].buf_type = session->ust_session->buffer_type;
3579 index++;
3580 }
3581 }
3582 rcu_read_unlock();
3583 }
3584 end:
3585 return nb_dom;
3586
3587 error:
3588 /* Return negative value to differentiate return code */
3589 return -ret;
3590 }
3591
3592
3593 /*
3594 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3595 */
3596 ssize_t cmd_list_channels(enum lttng_domain_type domain,
3597 struct ltt_session *session, struct lttng_channel **channels)
3598 {
3599 ssize_t nb_chan = 0, payload_size = 0, ret;
3600
3601 switch (domain) {
3602 case LTTNG_DOMAIN_KERNEL:
3603 if (session->kernel_session != NULL) {
3604 nb_chan = session->kernel_session->channel_count;
3605 }
3606 DBG3("Number of kernel channels %zd", nb_chan);
3607 if (nb_chan <= 0) {
3608 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
3609 goto end;
3610 }
3611 break;
3612 case LTTNG_DOMAIN_UST:
3613 if (session->ust_session != NULL) {
3614 rcu_read_lock();
3615 nb_chan = lttng_ht_get_count(
3616 session->ust_session->domain_global.channels);
3617 rcu_read_unlock();
3618 }
3619 DBG3("Number of UST global channels %zd", nb_chan);
3620 if (nb_chan < 0) {
3621 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
3622 goto end;
3623 }
3624 break;
3625 default:
3626 ret = -LTTNG_ERR_UND;
3627 goto end;
3628 }
3629
3630 if (nb_chan > 0) {
3631 const size_t channel_size = sizeof(struct lttng_channel) +
3632 sizeof(struct lttng_channel_extended);
3633 struct lttng_channel_extended *channel_exts;
3634
3635 payload_size = nb_chan * channel_size;
3636 *channels = zmalloc(payload_size);
3637 if (*channels == NULL) {
3638 ret = -LTTNG_ERR_FATAL;
3639 goto end;
3640 }
3641
3642 channel_exts = ((void *) *channels) +
3643 (nb_chan * sizeof(struct lttng_channel));
3644 ret = list_lttng_channels(domain, session, *channels, channel_exts);
3645 if (ret != LTTNG_OK) {
3646 free(*channels);
3647 *channels = NULL;
3648 goto end;
3649 }
3650 } else {
3651 *channels = NULL;
3652 }
3653
3654 ret = payload_size;
3655 end:
3656 return ret;
3657 }
3658
3659 /*
3660 * Command LTTNG_LIST_EVENTS processed by the client thread.
3661 */
3662 ssize_t cmd_list_events(enum lttng_domain_type domain,
3663 struct ltt_session *session, char *channel_name,
3664 struct lttng_payload *payload)
3665 {
3666 int ret = 0;
3667 ssize_t nb_events = 0;
3668 struct lttcomm_event_command_header cmd_header = {};
3669 const size_t cmd_header_offset = payload->buffer.size;
3670
3671 ret = lttng_dynamic_buffer_append(
3672 &payload->buffer, &cmd_header, sizeof(cmd_header));
3673 if (ret) {
3674 ret = LTTNG_ERR_NOMEM;
3675 goto error;
3676 }
3677
3678 switch (domain) {
3679 case LTTNG_DOMAIN_KERNEL:
3680 if (session->kernel_session != NULL) {
3681 nb_events = list_lttng_kernel_events(channel_name,
3682 session->kernel_session, payload);
3683 }
3684 break;
3685 case LTTNG_DOMAIN_UST:
3686 {
3687 if (session->ust_session != NULL) {
3688 nb_events = list_lttng_ust_global_events(channel_name,
3689 &session->ust_session->domain_global,
3690 payload);
3691 }
3692 break;
3693 }
3694 case LTTNG_DOMAIN_LOG4J:
3695 case LTTNG_DOMAIN_JUL:
3696 case LTTNG_DOMAIN_PYTHON:
3697 if (session->ust_session) {
3698 struct lttng_ht_iter iter;
3699 struct agent *agt;
3700
3701 rcu_read_lock();
3702 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3703 &iter.iter, agt, node.node) {
3704 if (agt->domain == domain) {
3705 nb_events = list_lttng_agent_events(
3706 agt, payload);
3707 break;
3708 }
3709 }
3710 rcu_read_unlock();
3711 }
3712 break;
3713 default:
3714 ret = LTTNG_ERR_UND;
3715 goto error;
3716 }
3717
3718 ((struct lttcomm_event_command_header *) (payload->buffer.data +
3719 cmd_header_offset))->nb_events = (uint32_t) nb_events;
3720
3721 return nb_events;
3722
3723 error:
3724 /* Return negative value to differentiate return code */
3725 return -ret;
3726 }
3727
3728 /*
3729 * Using the session list, filled a lttng_session array to send back to the
3730 * client for session listing.
3731 *
3732 * The session list lock MUST be acquired before calling this function. Use
3733 * session_lock_list() and session_unlock_list().
3734 */
3735 void cmd_list_lttng_sessions(struct lttng_session *sessions,
3736 size_t session_count, uid_t uid, gid_t gid)
3737 {
3738 int ret;
3739 unsigned int i = 0;
3740 struct ltt_session *session;
3741 struct ltt_session_list *list = session_get_list();
3742 struct lttng_session_extended *extended =
3743 (typeof(extended)) (&sessions[session_count]);
3744
3745 DBG("Getting all available session for UID %d GID %d",
3746 uid, gid);
3747 /*
3748 * Iterate over session list and append data after the control struct in
3749 * the buffer.
3750 */
3751 cds_list_for_each_entry(session, &list->head, list) {
3752 if (!session_get(session)) {
3753 continue;
3754 }
3755 /*
3756 * Only list the sessions the user can control.
3757 */
3758 if (!session_access_ok(session, uid) ||
3759 session->destroyed) {
3760 session_put(session);
3761 continue;
3762 }
3763
3764 struct ltt_kernel_session *ksess = session->kernel_session;
3765 struct ltt_ust_session *usess = session->ust_session;
3766
3767 if (session->consumer->type == CONSUMER_DST_NET ||
3768 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3769 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3770 ret = build_network_session_path(sessions[i].path,
3771 sizeof(sessions[i].path), session);
3772 } else {
3773 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3774 session->consumer->dst.session_root_path);
3775 }
3776 if (ret < 0) {
3777 PERROR("snprintf session path");
3778 session_put(session);
3779 continue;
3780 }
3781
3782 strncpy(sessions[i].name, session->name, NAME_MAX);
3783 sessions[i].name[NAME_MAX - 1] = '\0';
3784 sessions[i].enabled = session->active;
3785 sessions[i].snapshot_mode = session->snapshot_mode;
3786 sessions[i].live_timer_interval = session->live_timer;
3787 extended[i].creation_time.value = (uint64_t) session->creation_time;
3788 extended[i].creation_time.is_set = 1;
3789 i++;
3790 session_put(session);
3791 }
3792 }
3793
3794 /*
3795 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3796 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3797 */
3798 int cmd_data_pending(struct ltt_session *session)
3799 {
3800 int ret;
3801 struct ltt_kernel_session *ksess = session->kernel_session;
3802 struct ltt_ust_session *usess = session->ust_session;
3803
3804 assert(session);
3805
3806 DBG("Data pending for session %s", session->name);
3807
3808 /* Session MUST be stopped to ask for data availability. */
3809 if (session->active) {
3810 ret = LTTNG_ERR_SESSION_STARTED;
3811 goto error;
3812 } else {
3813 /*
3814 * If stopped, just make sure we've started before else the above call
3815 * will always send that there is data pending.
3816 *
3817 * The consumer assumes that when the data pending command is received,
3818 * the trace has been started before or else no output data is written
3819 * by the streams which is a condition for data pending. So, this is
3820 * *VERY* important that we don't ask the consumer before a start
3821 * trace.
3822 */
3823 if (!session->has_been_started) {
3824 ret = 0;
3825 goto error;
3826 }
3827 }
3828
3829 /* A rotation is still pending, we have to wait. */
3830 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
3831 DBG("Rotate still pending for session %s", session->name);
3832 ret = 1;
3833 goto error;
3834 }
3835
3836 if (ksess && ksess->consumer) {
3837 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3838 if (ret == 1) {
3839 /* Data is still being extracted for the kernel. */
3840 goto error;
3841 }
3842 }
3843
3844 if (usess && usess->consumer) {
3845 ret = consumer_is_data_pending(usess->id, usess->consumer);
3846 if (ret == 1) {
3847 /* Data is still being extracted for the kernel. */
3848 goto error;
3849 }
3850 }
3851
3852 /* Data is ready to be read by a viewer */
3853 ret = 0;
3854
3855 error:
3856 return ret;
3857 }
3858
3859 /*
3860 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3861 *
3862 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3863 */
3864 int cmd_snapshot_add_output(struct ltt_session *session,
3865 const struct lttng_snapshot_output *output, uint32_t *id)
3866 {
3867 int ret;
3868 struct snapshot_output *new_output;
3869
3870 assert(session);
3871 assert(output);
3872
3873 DBG("Cmd snapshot add output for session %s", session->name);
3874
3875 /*
3876 * Can't create an output if the session is not set in no-output mode.
3877 */
3878 if (session->output_traces) {
3879 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3880 goto error;
3881 }
3882
3883 if (session->has_non_mmap_channel) {
3884 ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
3885 goto error;
3886 }
3887
3888 /* Only one output is allowed until we have the "tee" feature. */
3889 if (session->snapshot.nb_output == 1) {
3890 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3891 goto error;
3892 }
3893
3894 new_output = snapshot_output_alloc();
3895 if (!new_output) {
3896 ret = LTTNG_ERR_NOMEM;
3897 goto error;
3898 }
3899
3900 ret = snapshot_output_init(session, output->max_size, output->name,
3901 output->ctrl_url, output->data_url, session->consumer, new_output,
3902 &session->snapshot);
3903 if (ret < 0) {
3904 if (ret == -ENOMEM) {
3905 ret = LTTNG_ERR_NOMEM;
3906 } else {
3907 ret = LTTNG_ERR_INVALID;
3908 }
3909 goto free_error;
3910 }
3911
3912 rcu_read_lock();
3913 snapshot_add_output(&session->snapshot, new_output);
3914 if (id) {
3915 *id = new_output->id;
3916 }
3917 rcu_read_unlock();
3918
3919 return LTTNG_OK;
3920
3921 free_error:
3922 snapshot_output_destroy(new_output);
3923 error:
3924 return ret;
3925 }
3926
3927 /*
3928 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3929 *
3930 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3931 */
3932 int cmd_snapshot_del_output(struct ltt_session *session,
3933 const struct lttng_snapshot_output *output)
3934 {
3935 int ret;
3936 struct snapshot_output *sout = NULL;
3937
3938 assert(session);
3939 assert(output);
3940
3941 rcu_read_lock();
3942
3943 /*
3944 * Permission denied to create an output if the session is not
3945 * set in no output mode.
3946 */
3947 if (session->output_traces) {
3948 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3949 goto error;
3950 }
3951
3952 if (output->id) {
3953 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
3954 session->name);
3955 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
3956 } else if (*output->name != '\0') {
3957 DBG("Cmd snapshot del output name %s for session %s", output->name,
3958 session->name);
3959 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
3960 }
3961 if (!sout) {
3962 ret = LTTNG_ERR_INVALID;
3963 goto error;
3964 }
3965
3966 snapshot_delete_output(&session->snapshot, sout);
3967 snapshot_output_destroy(sout);
3968 ret = LTTNG_OK;
3969
3970 error:
3971 rcu_read_unlock();
3972 return ret;
3973 }
3974
3975 /*
3976 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
3977 *
3978 * If no output is available, outputs is untouched and 0 is returned.
3979 *
3980 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
3981 */
3982 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
3983 struct lttng_snapshot_output **outputs)
3984 {
3985 int ret, idx = 0;
3986 struct lttng_snapshot_output *list = NULL;
3987 struct lttng_ht_iter iter;
3988 struct snapshot_output *output;
3989
3990 assert(session);
3991 assert(outputs);
3992
3993 DBG("Cmd snapshot list outputs for session %s", session->name);
3994
3995 /*
3996 * Permission denied to create an output if the session is not
3997 * set in no output mode.
3998 */
3999 if (session->output_traces) {
4000 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4001 goto end;
4002 }
4003
4004 if (session->snapshot.nb_output == 0) {
4005 ret = 0;
4006 goto end;
4007 }
4008
4009 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
4010 if (!list) {
4011 ret = -LTTNG_ERR_NOMEM;
4012 goto end;
4013 }
4014
4015 /* Copy list from session to the new list object. */
4016 rcu_read_lock();
4017 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
4018 output, node.node) {
4019 assert(output->consumer);
4020 list[idx].id = output->id;
4021 list[idx].max_size = output->max_size;
4022 if (lttng_strncpy(list[idx].name, output->name,
4023 sizeof(list[idx].name))) {
4024 ret = -LTTNG_ERR_INVALID;
4025 goto error;
4026 }
4027 if (output->consumer->type == CONSUMER_DST_LOCAL) {
4028 if (lttng_strncpy(list[idx].ctrl_url,
4029 output->consumer->dst.session_root_path,
4030 sizeof(list[idx].ctrl_url))) {
4031 ret = -LTTNG_ERR_INVALID;
4032 goto error;
4033 }
4034 } else {
4035 /* Control URI. */
4036 ret = uri_to_str_url(&output->consumer->dst.net.control,
4037 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
4038 if (ret < 0) {
4039 ret = -LTTNG_ERR_NOMEM;
4040 goto error;
4041 }
4042
4043 /* Data URI. */
4044 ret = uri_to_str_url(&output->consumer->dst.net.data,
4045 list[idx].data_url, sizeof(list[idx].data_url));
4046 if (ret < 0) {
4047 ret = -LTTNG_ERR_NOMEM;
4048 goto error;
4049 }
4050 }
4051 idx++;
4052 }
4053
4054 *outputs = list;
4055 list = NULL;
4056 ret = session->snapshot.nb_output;
4057 error:
4058 rcu_read_unlock();
4059 free(list);
4060 end:
4061 return ret;
4062 }
4063
4064 /*
4065 * Check if we can regenerate the metadata for this session.
4066 * Only kernel, UST per-uid and non-live sessions are supported.
4067 *
4068 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
4069 */
4070 static
4071 int check_regenerate_metadata_support(struct ltt_session *session)
4072 {
4073 int ret;
4074
4075 assert(session);
4076
4077 if (session->live_timer != 0) {
4078 ret = LTTNG_ERR_LIVE_SESSION;
4079 goto end;
4080 }
4081 if (!session->active) {
4082 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4083 goto end;
4084 }
4085 if (session->ust_session) {
4086 switch (session->ust_session->buffer_type) {
4087 case LTTNG_BUFFER_PER_UID:
4088 break;
4089 case LTTNG_BUFFER_PER_PID:
4090 ret = LTTNG_ERR_PER_PID_SESSION;
4091 goto end;
4092 default:
4093 assert(0);
4094 ret = LTTNG_ERR_UNK;
4095 goto end;
4096 }
4097 }
4098 if (session->consumer->type == CONSUMER_DST_NET &&
4099 session->consumer->relay_minor_version < 8) {
4100 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
4101 goto end;
4102 }
4103 ret = 0;
4104
4105 end:
4106 return ret;
4107 }
4108
4109 static
4110 int clear_metadata_file(int fd)
4111 {
4112 int ret;
4113 off_t lseek_ret;
4114
4115 lseek_ret = lseek(fd, 0, SEEK_SET);
4116 if (lseek_ret < 0) {
4117 PERROR("lseek");
4118 ret = -1;
4119 goto end;
4120 }
4121
4122 ret = ftruncate(fd, 0);
4123 if (ret < 0) {
4124 PERROR("ftruncate");
4125 goto end;
4126 }
4127
4128 end:
4129 return ret;
4130 }
4131
4132 static
4133 int ust_regenerate_metadata(struct ltt_ust_session *usess)
4134 {
4135 int ret = 0;
4136 struct buffer_reg_uid *uid_reg = NULL;
4137 struct buffer_reg_session *session_reg = NULL;
4138
4139 rcu_read_lock();
4140 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
4141 struct ust_registry_session *registry;
4142 struct ust_registry_channel *chan;
4143 struct lttng_ht_iter iter_chan;
4144
4145 session_reg = uid_reg->registry;
4146 registry = session_reg->reg.ust;
4147
4148 pthread_mutex_lock(&registry->lock);
4149 registry->metadata_len_sent = 0;
4150 memset(registry->metadata, 0, registry->metadata_alloc_len);
4151 registry->metadata_len = 0;
4152 registry->metadata_version++;
4153 if (registry->metadata_fd > 0) {
4154 /* Clear the metadata file's content. */
4155 ret = clear_metadata_file(registry->metadata_fd);
4156 if (ret) {
4157 pthread_mutex_unlock(&registry->lock);
4158 goto end;
4159 }
4160 }
4161
4162 ret = ust_metadata_session_statedump(registry, NULL,
4163 registry->major, registry->minor);
4164 if (ret) {
4165 pthread_mutex_unlock(&registry->lock);
4166 ERR("Failed to generate session metadata (err = %d)",
4167 ret);
4168 goto end;
4169 }
4170 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
4171 chan, node.node) {
4172 struct ust_registry_event *event;
4173 struct lttng_ht_iter iter_event;
4174
4175 ret = ust_metadata_channel_statedump(registry, chan);
4176 if (ret) {
4177 pthread_mutex_unlock(&registry->lock);
4178 ERR("Failed to generate channel metadata "
4179 "(err = %d)", ret);
4180 goto end;
4181 }
4182 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
4183 event, node.node) {
4184 ret = ust_metadata_event_statedump(registry,
4185 chan, event);
4186 if (ret) {
4187 pthread_mutex_unlock(&registry->lock);
4188 ERR("Failed to generate event metadata "
4189 "(err = %d)", ret);
4190 goto end;
4191 }
4192 }
4193 }
4194 pthread_mutex_unlock(&registry->lock);
4195 }
4196
4197 end:
4198 rcu_read_unlock();
4199 return ret;
4200 }
4201
4202 /*
4203 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
4204 *
4205 * Ask the consumer to truncate the existing metadata file(s) and
4206 * then regenerate the metadata. Live and per-pid sessions are not
4207 * supported and return an error.
4208 *
4209 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4210 */
4211 int cmd_regenerate_metadata(struct ltt_session *session)
4212 {
4213 int ret;
4214
4215 assert(session);
4216
4217 ret = check_regenerate_metadata_support(session);
4218 if (ret) {
4219 goto end;
4220 }
4221
4222 if (session->kernel_session) {
4223 ret = kernctl_session_regenerate_metadata(
4224 session->kernel_session->fd);
4225 if (ret < 0) {
4226 ERR("Failed to regenerate the kernel metadata");
4227 goto end;
4228 }
4229 }
4230
4231 if (session->ust_session) {
4232 ret = ust_regenerate_metadata(session->ust_session);
4233 if (ret < 0) {
4234 ERR("Failed to regenerate the UST metadata");
4235 goto end;
4236 }
4237 }
4238 DBG("Cmd metadata regenerate for session %s", session->name);
4239 ret = LTTNG_OK;
4240
4241 end:
4242 return ret;
4243 }
4244
4245 /*
4246 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
4247 *
4248 * Ask the tracer to regenerate a new statedump.
4249 *
4250 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4251 */
4252 int cmd_regenerate_statedump(struct ltt_session *session)
4253 {
4254 int ret;
4255
4256 assert(session);
4257
4258 if (!session->active) {
4259 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4260 goto end;
4261 }
4262
4263 if (session->kernel_session) {
4264 ret = kernctl_session_regenerate_statedump(
4265 session->kernel_session->fd);
4266 /*
4267 * Currently, the statedump in kernel can only fail if out
4268 * of memory.
4269 */
4270 if (ret < 0) {
4271 if (ret == -ENOMEM) {
4272 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
4273 } else {
4274 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4275 }
4276 ERR("Failed to regenerate the kernel statedump");
4277 goto end;
4278 }
4279 }
4280
4281 if (session->ust_session) {
4282 ret = ust_app_regenerate_statedump_all(session->ust_session);
4283 /*
4284 * Currently, the statedump in UST always returns 0.
4285 */
4286 if (ret < 0) {
4287 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4288 ERR("Failed to regenerate the UST statedump");
4289 goto end;
4290 }
4291 }
4292 DBG("Cmd regenerate statedump for session %s", session->name);
4293 ret = LTTNG_OK;
4294
4295 end:
4296 return ret;
4297 }
4298
4299 static
4300 enum lttng_error_code synchronize_tracer_notifier_register(
4301 struct notification_thread_handle *notification_thread,
4302 struct lttng_trigger *trigger, const struct lttng_credentials *cmd_creds)
4303 {
4304 enum lttng_error_code ret_code;
4305 const struct lttng_condition *condition =
4306 lttng_trigger_get_const_condition(trigger);
4307 const char *trigger_name;
4308 uid_t trigger_owner;
4309 enum lttng_trigger_status trigger_status;
4310 const enum lttng_domain_type trigger_domain =
4311 lttng_trigger_get_underlying_domain_type_restriction(
4312 trigger);
4313
4314 trigger_status = lttng_trigger_get_owner_uid(trigger, &trigger_owner);
4315 assert(trigger_status == LTTNG_TRIGGER_STATUS_OK);
4316
4317 assert(condition);
4318 assert(lttng_condition_get_type(condition) ==
4319 LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES);
4320
4321 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
4322 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ?
4323 trigger_name : "(anonymous)";
4324
4325 session_lock_list();
4326 switch (trigger_domain) {
4327 case LTTNG_DOMAIN_KERNEL:
4328 {
4329 ret_code = kernel_register_event_notifier(trigger, cmd_creds);
4330 if (ret_code != LTTNG_OK) {
4331 enum lttng_error_code notif_thread_unregister_ret;
4332
4333 notif_thread_unregister_ret =
4334 notification_thread_command_unregister_trigger(
4335 notification_thread, trigger);
4336
4337 if (notif_thread_unregister_ret != LTTNG_OK) {
4338 /* Return the original error code. */
4339 ERR("Failed to unregister trigger from notification thread during error recovery: trigger name = '%s', trigger owner uid = %d, error code = %d",
4340 trigger_name,
4341 (int) trigger_owner,
4342 ret_code);
4343 }
4344 }
4345 break;
4346 }
4347 case LTTNG_DOMAIN_UST:
4348 ust_app_global_update_all_event_notifier_rules();
4349 break;
4350 case LTTNG_DOMAIN_JUL:
4351 case LTTNG_DOMAIN_LOG4J:
4352 case LTTNG_DOMAIN_PYTHON:
4353 {
4354 /* Agent domains. */
4355 struct agent *agt = agent_find_by_event_notifier_domain(
4356 trigger_domain);
4357
4358 if (!agt) {
4359 agt = agent_create(trigger_domain);
4360 if (!agt) {
4361 ret_code = LTTNG_ERR_NOMEM;
4362 goto end_unlock_session_list;
4363 }
4364
4365 agent_add(agt, the_trigger_agents_ht_by_domain);
4366 }
4367
4368 ret_code = trigger_agent_enable(trigger, agt);
4369 if (ret_code != LTTNG_OK) {
4370 goto end_unlock_session_list;
4371 }
4372
4373 break;
4374 }
4375 case LTTNG_DOMAIN_NONE:
4376 default:
4377 abort();
4378 }
4379
4380 ret_code = LTTNG_OK;
4381 end_unlock_session_list:
4382 session_unlock_list();
4383 return ret_code;
4384 }
4385
4386 enum lttng_error_code cmd_register_trigger(const struct lttng_credentials *cmd_creds,
4387 struct lttng_trigger *trigger,
4388 bool is_trigger_anonymous,
4389 struct notification_thread_handle *notification_thread,
4390 struct lttng_trigger **return_trigger)
4391 {
4392 enum lttng_error_code ret_code;
4393 const char *trigger_name;
4394 uid_t trigger_owner;
4395 enum lttng_trigger_status trigger_status;
4396
4397 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
4398 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ?
4399 trigger_name : "(anonymous)";
4400
4401 trigger_status = lttng_trigger_get_owner_uid(
4402 trigger, &trigger_owner);
4403 assert(trigger_status == LTTNG_TRIGGER_STATUS_OK);
4404
4405 DBG("Running register trigger command: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4406 trigger_name, (int) trigger_owner,
4407 (int) lttng_credentials_get_uid(cmd_creds));
4408
4409 /*
4410 * Validate the trigger credentials against the command credentials.
4411 * Only the root user can register a trigger with non-matching
4412 * credentials.
4413 */
4414 if (!lttng_credentials_is_equal_uid(
4415 lttng_trigger_get_credentials(trigger),
4416 cmd_creds)) {
4417 if (lttng_credentials_get_uid(cmd_creds) != 0) {
4418 ERR("Trigger credentials do not match the command credentials: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4419 trigger_name, (int) trigger_owner,
4420 (int) lttng_credentials_get_uid(cmd_creds));
4421 ret_code = LTTNG_ERR_INVALID_TRIGGER;
4422 goto end;
4423 }
4424 }
4425
4426 /*
4427 * The bytecode generation also serves as a validation step for the
4428 * bytecode expressions.
4429 */
4430 ret_code = lttng_trigger_generate_bytecode(trigger, cmd_creds);
4431 if (ret_code != LTTNG_OK) {
4432 ERR("Failed to generate bytecode of trigger: trigger name = '%s', trigger owner uid = %d, error code = %d",
4433 trigger_name, (int) trigger_owner, ret_code);
4434 goto end;
4435 }
4436
4437 /*
4438 * A reference to the trigger is acquired by the notification thread.
4439 * It is safe to return the same trigger to the caller since it the
4440 * other user holds a reference.
4441 *
4442 * The trigger is modified during the execution of the
4443 * "register trigger" command. However, by the time the command returns,
4444 * it is safe to use without any locking as its properties are
4445 * immutable.
4446 */
4447 ret_code = notification_thread_command_register_trigger(
4448 notification_thread, trigger, is_trigger_anonymous);
4449 if (ret_code != LTTNG_OK) {
4450 DBG("Failed to register trigger to notification thread: trigger name = '%s', trigger owner uid = %d, error code = %d",
4451 trigger_name, (int) trigger_owner, ret_code);
4452 goto end;
4453 }
4454
4455 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
4456 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ?
4457 trigger_name : "(anonymous)";
4458
4459 /*
4460 * Synchronize tracers if the trigger adds an event notifier.
4461 */
4462 if (lttng_trigger_needs_tracer_notifier(trigger)) {
4463 ret_code = synchronize_tracer_notifier_register(notification_thread,
4464 trigger, cmd_creds);
4465 if (ret_code != LTTNG_OK) {
4466 ERR("Error registering tracer notifier: %s",
4467 lttng_strerror(-ret_code));
4468 goto end;
4469 }
4470 }
4471
4472 /*
4473 * Return an updated trigger to the client.
4474 *
4475 * Since a modified version of the same trigger is returned, acquire a
4476 * reference to the trigger so the caller doesn't have to care if those
4477 * are distinct instances or not.
4478 */
4479 if (ret_code == LTTNG_OK) {
4480 lttng_trigger_get(trigger);
4481 *return_trigger = trigger;
4482 /* Ownership of trigger was transferred to caller. */
4483 trigger = NULL;
4484 }
4485 end:
4486 return ret_code;
4487 }
4488
4489 static
4490 enum lttng_error_code synchronize_tracer_notifier_unregister(
4491 const struct lttng_trigger *trigger)
4492 {
4493 enum lttng_error_code ret_code;
4494 const struct lttng_condition *condition =
4495 lttng_trigger_get_const_condition(trigger);
4496 const enum lttng_domain_type trigger_domain =
4497 lttng_trigger_get_underlying_domain_type_restriction(
4498 trigger);
4499
4500 assert(condition);
4501 assert(lttng_condition_get_type(condition) ==
4502 LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES);
4503
4504 session_lock_list();
4505 switch (trigger_domain) {
4506 case LTTNG_DOMAIN_KERNEL:
4507 ret_code = kernel_unregister_event_notifier(trigger);
4508 if (ret_code != LTTNG_OK) {
4509 goto end_unlock_session_list;
4510 }
4511
4512 break;
4513 case LTTNG_DOMAIN_UST:
4514 ust_app_global_update_all_event_notifier_rules();
4515 break;
4516 case LTTNG_DOMAIN_JUL:
4517 case LTTNG_DOMAIN_LOG4J:
4518 case LTTNG_DOMAIN_PYTHON:
4519 {
4520 /* Agent domains. */
4521 struct agent *agt = agent_find_by_event_notifier_domain(
4522 trigger_domain);
4523
4524 /*
4525 * This trigger was never registered in the first place. Calling
4526 * this function under those circumstances is an internal error.
4527 */
4528 assert(agt);
4529 ret_code = trigger_agent_disable(trigger, agt);
4530 if (ret_code != LTTNG_OK) {
4531 goto end_unlock_session_list;
4532 }
4533
4534 break;
4535 }
4536 case LTTNG_DOMAIN_NONE:
4537 default:
4538 abort();
4539 }
4540
4541 ret_code = LTTNG_OK;
4542
4543 end_unlock_session_list:
4544 session_unlock_list();
4545 return ret_code;
4546 }
4547
4548 enum lttng_error_code cmd_unregister_trigger(const struct lttng_credentials *cmd_creds,
4549 const struct lttng_trigger *trigger,
4550 struct notification_thread_handle *notification_thread)
4551 {
4552 enum lttng_error_code ret_code;
4553 const char *trigger_name;
4554 uid_t trigger_owner;
4555 enum lttng_trigger_status trigger_status;
4556 struct lttng_trigger *sessiond_trigger = NULL;
4557
4558 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
4559 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ? trigger_name : "(anonymous)";
4560 trigger_status = lttng_trigger_get_owner_uid(trigger, &trigger_owner);
4561 assert(trigger_status == LTTNG_TRIGGER_STATUS_OK);
4562
4563 DBG("Running unregister trigger command: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4564 trigger_name, (int) trigger_owner,
4565 (int) lttng_credentials_get_uid(cmd_creds));
4566
4567 /*
4568 * Validate the trigger credentials against the command credentials.
4569 * Only the root user can unregister a trigger with non-matching
4570 * credentials.
4571 */
4572 if (!lttng_credentials_is_equal_uid(
4573 lttng_trigger_get_credentials(trigger),
4574 cmd_creds)) {
4575 if (lttng_credentials_get_uid(cmd_creds) != 0) {
4576 ERR("Trigger credentials do not match the command credentials: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4577 trigger_name, (int) trigger_owner,
4578 (int) lttng_credentials_get_uid(cmd_creds));
4579 ret_code = LTTNG_ERR_INVALID_TRIGGER;
4580 goto end;
4581 }
4582 }
4583
4584 /* Fetch the sessiond side trigger object. */
4585 ret_code = notification_thread_command_get_trigger(
4586 notification_thread, trigger, &sessiond_trigger);
4587 if (ret_code != LTTNG_OK) {
4588 DBG("Failed to get trigger from notification thread during unregister: trigger name = '%s', trigger owner uid = %d, error code = %d",
4589 trigger_name, (int) trigger_owner, ret_code);
4590 goto end;
4591 }
4592
4593 assert(sessiond_trigger);
4594
4595 /*
4596 * From this point on, no matter what, consider the trigger
4597 * unregistered.
4598 *
4599 * We set the unregistered state of the sessiond side trigger object in
4600 * the client thread since we want to minimize the possibility of the
4601 * notification thread being stalled due to a long execution of an
4602 * action that required the trigger lock.
4603 */
4604 lttng_trigger_set_as_unregistered(sessiond_trigger);
4605
4606 ret_code = notification_thread_command_unregister_trigger(notification_thread,
4607 trigger);
4608 if (ret_code != LTTNG_OK) {
4609 DBG("Failed to unregister trigger from notification thread: trigger name = '%s', trigger owner uid = %d, error code = %d",
4610 trigger_name, (int) trigger_owner, ret_code);
4611 goto end;
4612 }
4613
4614 /*
4615 * Synchronize tracers if the trigger removes an event notifier.
4616 * Do this even if the trigger unregistration failed to at least stop
4617 * the tracers from producing notifications associated with this
4618 * event notifier.
4619 */
4620 if (lttng_trigger_needs_tracer_notifier(trigger)) {
4621 ret_code = synchronize_tracer_notifier_unregister(trigger);
4622 if (ret_code != LTTNG_OK) {
4623 ERR("Error unregistering trigger to tracer.");
4624 goto end;
4625 }
4626
4627 }
4628
4629 end:
4630 lttng_trigger_put(sessiond_trigger);
4631 return ret_code;
4632 }
4633
4634 int cmd_list_triggers(struct command_ctx *cmd_ctx,
4635 struct notification_thread_handle *notification_thread,
4636 struct lttng_triggers **return_triggers)
4637 {
4638 int ret = 0;
4639 enum lttng_error_code ret_code;
4640 struct lttng_triggers *triggers = NULL;
4641
4642 /* Get the set of triggers from the notification thread. */
4643 ret_code = notification_thread_command_list_triggers(
4644 notification_thread, cmd_ctx->creds.uid, &triggers);
4645 if (ret_code != LTTNG_OK) {
4646 ret = ret_code;
4647 goto end;
4648 }
4649
4650 *return_triggers = triggers;
4651 triggers = NULL;
4652 ret = LTTNG_OK;
4653 end:
4654 lttng_triggers_destroy(triggers);
4655 return ret;
4656 }
4657
4658 enum lttng_error_code cmd_execute_error_query(const struct lttng_credentials *cmd_creds,
4659 const struct lttng_error_query *query,
4660 struct lttng_error_query_results **_results,
4661 struct notification_thread_handle *notification_thread)
4662 {
4663 enum lttng_error_code ret_code;
4664 const struct lttng_trigger *query_target_trigger;
4665 struct lttng_action *query_target_action = NULL;
4666 struct lttng_trigger *matching_trigger = NULL;
4667 const char *trigger_name;
4668 uid_t trigger_owner;
4669 enum lttng_trigger_status trigger_status;
4670 struct lttng_error_query_results *results = NULL;
4671
4672 switch (lttng_error_query_get_target_type(query)) {
4673 case LTTNG_ERROR_QUERY_TARGET_TYPE_TRIGGER:
4674 query_target_trigger = lttng_error_query_trigger_borrow_target(query);
4675 break;
4676 case LTTNG_ERROR_QUERY_TARGET_TYPE_ACTION:
4677 query_target_trigger = lttng_error_query_action_borrow_trigger_target(
4678 query);
4679 break;
4680 default:
4681 abort();
4682 }
4683
4684 assert(query_target_trigger);
4685
4686 ret_code = notification_thread_command_get_trigger(notification_thread,
4687 query_target_trigger, &matching_trigger);
4688 if (ret_code != LTTNG_OK) {
4689 goto end;
4690 }
4691
4692 /* No longer needed. */
4693 query_target_trigger = NULL;
4694
4695 if (lttng_error_query_get_target_type(query) ==
4696 LTTNG_ERROR_QUERY_TARGET_TYPE_ACTION) {
4697 /* Get the sessiond-side version of the target action. */
4698 query_target_action =
4699 lttng_error_query_action_borrow_action_target(
4700 query, matching_trigger);
4701 }
4702
4703 trigger_status = lttng_trigger_get_name(matching_trigger, &trigger_name);
4704 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ?
4705 trigger_name : "(anonymous)";
4706 trigger_status = lttng_trigger_get_owner_uid(matching_trigger,
4707 &trigger_owner);
4708 assert(trigger_status == LTTNG_TRIGGER_STATUS_OK);
4709
4710 results = lttng_error_query_results_create();
4711 if (!results) {
4712 ret_code = LTTNG_ERR_NOMEM;
4713 goto end;
4714 }
4715
4716 DBG("Running \"execute error query\" command: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4717 trigger_name, (int) trigger_owner,
4718 (int) lttng_credentials_get_uid(cmd_creds));
4719
4720 /*
4721 * Validate the trigger credentials against the command credentials.
4722 * Only the root user can target a trigger with non-matching
4723 * credentials.
4724 */
4725 if (!lttng_credentials_is_equal_uid(
4726 lttng_trigger_get_credentials(matching_trigger),
4727 cmd_creds)) {
4728 if (lttng_credentials_get_uid(cmd_creds) != 0) {
4729 ERR("Trigger credentials do not match the command credentials: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4730 trigger_name, (int) trigger_owner,
4731 (int) lttng_credentials_get_uid(cmd_creds));
4732 ret_code = LTTNG_ERR_INVALID_TRIGGER;
4733 goto end;
4734 }
4735 }
4736
4737 switch (lttng_error_query_get_target_type(query)) {
4738 case LTTNG_ERROR_QUERY_TARGET_TYPE_TRIGGER:
4739 trigger_status = lttng_trigger_add_error_results(
4740 matching_trigger, results);
4741
4742 switch (trigger_status) {
4743 case LTTNG_TRIGGER_STATUS_OK:
4744 break;
4745 default:
4746 ret_code = LTTNG_ERR_UNK;
4747 goto end;
4748 }
4749
4750 break;
4751 case LTTNG_ERROR_QUERY_TARGET_TYPE_ACTION:
4752 {
4753 const enum lttng_action_status action_status =
4754 lttng_action_add_error_query_results(
4755 query_target_action, results);
4756
4757 switch (action_status) {
4758 case LTTNG_ACTION_STATUS_OK:
4759 break;
4760 default:
4761 ret_code = LTTNG_ERR_UNK;
4762 goto end;
4763 }
4764
4765 break;
4766 }
4767 default:
4768 abort();
4769 break;
4770 }
4771
4772 *_results = results;
4773 results = NULL;
4774 ret_code = LTTNG_OK;
4775 end:
4776 lttng_trigger_put(matching_trigger);
4777 lttng_error_query_results_destroy(results);
4778 return ret_code;
4779 }
4780
4781 /*
4782 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4783 * snapshot output is *not* set with a remote destination.
4784 *
4785 * Return LTTNG_OK on success or a LTTNG_ERR code.
4786 */
4787 static enum lttng_error_code set_relayd_for_snapshot(
4788 struct consumer_output *output,
4789 const struct ltt_session *session)
4790 {
4791 enum lttng_error_code status = LTTNG_OK;
4792 struct lttng_ht_iter iter;
4793 struct consumer_socket *socket;
4794 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
4795 const char *base_path;
4796
4797 assert(output);
4798 assert(session);
4799
4800 DBG2("Set relayd object from snapshot output");
4801
4802 if (session->current_trace_chunk) {
4803 enum lttng_trace_chunk_status chunk_status =
4804 lttng_trace_chunk_get_id(
4805 session->current_trace_chunk,
4806 &current_chunk_id.value);
4807
4808 if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK) {
4809 current_chunk_id.is_set = true;
4810 } else {
4811 ERR("Failed to get current trace chunk id");
4812 status = LTTNG_ERR_UNK;
4813 goto error;
4814 }
4815 }
4816
4817 /* Ignore if snapshot consumer output is not network. */
4818 if (output->type != CONSUMER_DST_NET) {
4819 goto error;
4820 }
4821
4822 /*
4823 * The snapshot record URI base path overrides the session
4824 * base path.
4825 */
4826 if (output->dst.net.control.subdir[0] != '\0') {
4827 base_path = output->dst.net.control.subdir;
4828 } else {
4829 base_path = session->base_path;
4830 }
4831
4832 /*
4833 * For each consumer socket, create and send the relayd object of the
4834 * snapshot output.
4835 */
4836 rcu_read_lock();
4837 cds_lfht_for_each_entry(output->socks->ht, &iter.iter,
4838 socket, node.node) {
4839 pthread_mutex_lock(socket->lock);
4840 status = send_consumer_relayd_sockets(0, session->id,
4841 output, socket,
4842 session->name, session->hostname,
4843 base_path,
4844 session->live_timer,
4845 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
4846 session->creation_time,
4847 session->name_contains_creation_time);
4848 pthread_mutex_unlock(socket->lock);
4849 if (status != LTTNG_OK) {
4850 rcu_read_unlock();
4851 goto error;
4852 }
4853 }
4854 rcu_read_unlock();
4855
4856 error:
4857 return status;
4858 }
4859
4860 /*
4861 * Record a kernel snapshot.
4862 *
4863 * Return LTTNG_OK on success or a LTTNG_ERR code.
4864 */
4865 static enum lttng_error_code record_kernel_snapshot(
4866 struct ltt_kernel_session *ksess,
4867 const struct consumer_output *output,
4868 const struct ltt_session *session,
4869 int wait, uint64_t nb_packets_per_stream)
4870 {
4871 enum lttng_error_code status;
4872
4873 assert(ksess);
4874 assert(output);
4875 assert(session);
4876
4877 status = kernel_snapshot_record(
4878 ksess, output, wait, nb_packets_per_stream);
4879 return status;
4880 }
4881
4882 /*
4883 * Record a UST snapshot.
4884 *
4885 * Returns LTTNG_OK on success or a LTTNG_ERR error code.
4886 */
4887 static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
4888 const struct consumer_output *output,
4889 const struct ltt_session *session,
4890 int wait, uint64_t nb_packets_per_stream)
4891 {
4892 enum lttng_error_code status;
4893
4894 assert(usess);
4895 assert(output);
4896 assert(session);
4897
4898 status = ust_app_snapshot_record(
4899 usess, output, wait, nb_packets_per_stream);
4900 return status;
4901 }
4902
4903 static
4904 uint64_t get_session_size_one_more_packet_per_stream(
4905 const struct ltt_session *session, uint64_t cur_nr_packets)
4906 {
4907 uint64_t tot_size = 0;
4908
4909 if (session->kernel_session) {
4910 struct ltt_kernel_channel *chan;
4911 const struct ltt_kernel_session *ksess =
4912 session->kernel_session;
4913
4914 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
4915 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
4916 /*
4917 * Don't take channel into account if we
4918 * already grab all its packets.
4919 */
4920 continue;
4921 }
4922 tot_size += chan->channel->attr.subbuf_size
4923 * chan->stream_count;
4924 }
4925 }
4926
4927 if (session->ust_session) {
4928 const struct ltt_ust_session *usess = session->ust_session;
4929
4930 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
4931 cur_nr_packets);
4932 }
4933
4934 return tot_size;
4935 }
4936
4937 /*
4938 * Calculate the number of packets we can grab from each stream that
4939 * fits within the overall snapshot max size.
4940 *
4941 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
4942 * the number of packets per stream.
4943 *
4944 * TODO: this approach is not perfect: we consider the worse case
4945 * (packet filling the sub-buffers) as an upper bound, but we could do
4946 * better if we do this calculation while we actually grab the packet
4947 * content: we would know how much padding we don't actually store into
4948 * the file.
4949 *
4950 * This algorithm is currently bounded by the number of packets per
4951 * stream.
4952 *
4953 * Since we call this algorithm before actually grabbing the data, it's
4954 * an approximation: for instance, applications could appear/disappear
4955 * in between this call and actually grabbing data.
4956 */
4957 static
4958 int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
4959 uint64_t max_size)
4960 {
4961 int64_t size_left;
4962 uint64_t cur_nb_packets = 0;
4963
4964 if (!max_size) {
4965 return 0; /* Infinite */
4966 }
4967
4968 size_left = max_size;
4969 for (;;) {
4970 uint64_t one_more_packet_tot_size;
4971
4972 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(
4973 session, cur_nb_packets);
4974 if (!one_more_packet_tot_size) {
4975 /* We are already grabbing all packets. */
4976 break;
4977 }
4978 size_left -= one_more_packet_tot_size;
4979 if (size_left < 0) {
4980 break;
4981 }
4982 cur_nb_packets++;
4983 }
4984 if (!cur_nb_packets && size_left != max_size) {
4985 /* Not enough room to grab one packet of each stream, error. */
4986 return -1;
4987 }
4988 return cur_nb_packets;
4989 }
4990
4991 static
4992 enum lttng_error_code snapshot_record(struct ltt_session *session,
4993 const struct snapshot_output *snapshot_output, int wait)
4994 {
4995 int64_t nb_packets_per_stream;
4996 char snapshot_chunk_name[LTTNG_NAME_MAX];
4997 int ret;
4998 enum lttng_error_code ret_code = LTTNG_OK;
4999 struct lttng_trace_chunk *snapshot_trace_chunk;
5000 struct consumer_output *original_ust_consumer_output = NULL;
5001 struct consumer_output *original_kernel_consumer_output = NULL;
5002 struct consumer_output *snapshot_ust_consumer_output = NULL;
5003 struct consumer_output *snapshot_kernel_consumer_output = NULL;
5004
5005 ret = snprintf(snapshot_chunk_name, sizeof(snapshot_chunk_name),
5006 "%s-%s-%" PRIu64,
5007 snapshot_output->name,
5008 snapshot_output->datetime,
5009 snapshot_output->nb_snapshot);
5010 if (ret < 0 || ret >= sizeof(snapshot_chunk_name)) {
5011 ERR("Failed to format snapshot name");
5012 ret_code = LTTNG_ERR_INVALID;
5013 goto error;
5014 }
5015 DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
5016 snapshot_output->name, session->name,
5017 snapshot_chunk_name);
5018 if (!session->kernel_session && !session->ust_session) {
5019 ERR("Failed to record snapshot as no channels exist");
5020 ret_code = LTTNG_ERR_NO_CHANNEL;
5021 goto error;
5022 }
5023
5024 if (session->kernel_session) {
5025 original_kernel_consumer_output =
5026 session->kernel_session->consumer;
5027 snapshot_kernel_consumer_output =
5028 consumer_copy_output(snapshot_output->consumer);
5029 strcpy(snapshot_kernel_consumer_output->chunk_path,
5030 snapshot_chunk_name);
5031
5032 /* Copy the original domain subdir. */
5033 strcpy(snapshot_kernel_consumer_output->domain_subdir,
5034 original_kernel_consumer_output->domain_subdir);
5035
5036 ret = consumer_copy_sockets(snapshot_kernel_consumer_output,
5037 original_kernel_consumer_output);
5038 if (ret < 0) {
5039 ERR("Failed to copy consumer sockets from snapshot output configuration");
5040 ret_code = LTTNG_ERR_NOMEM;
5041 goto error;
5042 }
5043 ret_code = set_relayd_for_snapshot(
5044 snapshot_kernel_consumer_output, session);
5045 if (ret_code != LTTNG_OK) {
5046 ERR("Failed to setup relay daemon for kernel tracer snapshot");
5047 goto error;
5048 }
5049 session->kernel_session->consumer =
5050 snapshot_kernel_consumer_output;
5051 }
5052 if (session->ust_session) {
5053 original_ust_consumer_output = session->ust_session->consumer;
5054 snapshot_ust_consumer_output =
5055 consumer_copy_output(snapshot_output->consumer);
5056 strcpy(snapshot_ust_consumer_output->chunk_path,
5057 snapshot_chunk_name);
5058
5059 /* Copy the original domain subdir. */
5060 strcpy(snapshot_ust_consumer_output->domain_subdir,
5061 original_ust_consumer_output->domain_subdir);
5062
5063 ret = consumer_copy_sockets(snapshot_ust_consumer_output,
5064 original_ust_consumer_output);
5065 if (ret < 0) {
5066 ERR("Failed to copy consumer sockets from snapshot output configuration");
5067 ret_code = LTTNG_ERR_NOMEM;
5068 goto error;
5069 }
5070 ret_code = set_relayd_for_snapshot(
5071 snapshot_ust_consumer_output, session);
5072 if (ret_code != LTTNG_OK) {
5073 ERR("Failed to setup relay daemon for userspace tracer snapshot");
5074 goto error;
5075 }
5076 session->ust_session->consumer =
5077 snapshot_ust_consumer_output;
5078 }
5079
5080 snapshot_trace_chunk = session_create_new_trace_chunk(session,
5081 snapshot_kernel_consumer_output ?:
5082 snapshot_ust_consumer_output,
5083 consumer_output_get_base_path(
5084 snapshot_output->consumer),
5085 snapshot_chunk_name);
5086 if (!snapshot_trace_chunk) {
5087 ERR("Failed to create temporary trace chunk to record a snapshot of session \"%s\"",
5088 session->name);
5089 ret_code = LTTNG_ERR_CREATE_DIR_FAIL;
5090 goto error;
5091 }
5092 assert(!session->current_trace_chunk);
5093 ret = session_set_trace_chunk(session, snapshot_trace_chunk, NULL);
5094 lttng_trace_chunk_put(snapshot_trace_chunk);
5095 snapshot_trace_chunk = NULL;
5096 if (ret) {
5097 ERR("Failed to set temporary trace chunk to record a snapshot of session \"%s\"",
5098 session->name);
5099 ret_code = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
5100 goto error;
5101 }
5102
5103 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
5104 snapshot_output->max_size);
5105 if (nb_packets_per_stream < 0) {
5106 ret_code = LTTNG_ERR_MAX_SIZE_INVALID;
5107 goto error_close_trace_chunk;
5108 }
5109
5110 if (session->kernel_session) {
5111 ret_code = record_kernel_snapshot(session->kernel_session,
5112 snapshot_kernel_consumer_output, session,
5113 wait, nb_packets_per_stream);
5114 if (ret_code != LTTNG_OK) {
5115 goto error_close_trace_chunk;
5116 }
5117 }
5118
5119 if (session->ust_session) {
5120 ret_code = record_ust_snapshot(session->ust_session,
5121 snapshot_ust_consumer_output, session,
5122 wait, nb_packets_per_stream);
5123 if (ret_code != LTTNG_OK) {
5124 goto error_close_trace_chunk;
5125 }
5126 }
5127
5128 error_close_trace_chunk:
5129 if (session_set_trace_chunk(session, NULL, &snapshot_trace_chunk)) {
5130 ERR("Failed to release the current trace chunk of session \"%s\"",
5131 session->name);
5132 ret_code = LTTNG_ERR_UNK;
5133 }
5134
5135 if (session_close_trace_chunk(session, snapshot_trace_chunk,
5136 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION, NULL)) {
5137 /*
5138 * Don't goto end; make sure the chunk is closed for the session
5139 * to allow future snapshots.
5140 */
5141 ERR("Failed to close snapshot trace chunk of session \"%s\"",
5142 session->name);
5143 ret_code = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5144 }
5145 error:
5146 if (original_ust_consumer_output) {
5147 session->ust_session->consumer = original_ust_consumer_output;
5148 }
5149 if (original_kernel_consumer_output) {
5150 session->kernel_session->consumer =
5151 original_kernel_consumer_output;
5152 }
5153 consumer_output_put(snapshot_ust_consumer_output);
5154 consumer_output_put(snapshot_kernel_consumer_output);
5155 return ret_code;
5156 }
5157
5158 /*
5159 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
5160 *
5161 * The wait parameter is ignored so this call always wait for the snapshot to
5162 * complete before returning.
5163 *
5164 * Return LTTNG_OK on success or else a LTTNG_ERR code.
5165 */
5166 int cmd_snapshot_record(struct ltt_session *session,
5167 const struct lttng_snapshot_output *output, int wait)
5168 {
5169 enum lttng_error_code cmd_ret = LTTNG_OK;
5170 int ret;
5171 unsigned int snapshot_success = 0;
5172 char datetime[16];
5173 struct snapshot_output *tmp_output = NULL;
5174
5175 assert(session);
5176 assert(output);
5177
5178 DBG("Cmd snapshot record for session %s", session->name);
5179
5180 /* Get the datetime for the snapshot output directory. */
5181 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
5182 sizeof(datetime));
5183 if (!ret) {
5184 cmd_ret = LTTNG_ERR_INVALID;
5185 goto error;
5186 }
5187
5188 /*
5189 * Permission denied to create an output if the session is not
5190 * set in no output mode.
5191 */
5192 if (session->output_traces) {
5193 cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
5194 goto error;
5195 }
5196
5197 /* The session needs to be started at least once. */
5198 if (!session->has_been_started) {
5199 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
5200 goto error;
5201 }
5202
5203 /* Use temporary output for the session. */
5204 if (*output->ctrl_url != '\0') {
5205 tmp_output = snapshot_output_alloc();
5206 if (!tmp_output) {
5207 cmd_ret = LTTNG_ERR_NOMEM;
5208 goto error;
5209 }
5210
5211 ret = snapshot_output_init(session, output->max_size,
5212 output->name,
5213 output->ctrl_url, output->data_url,
5214 session->consumer,
5215 tmp_output, NULL);
5216 if (ret < 0) {
5217 if (ret == -ENOMEM) {
5218 cmd_ret = LTTNG_ERR_NOMEM;
5219 } else {
5220 cmd_ret = LTTNG_ERR_INVALID;
5221 }
5222 goto error;
5223 }
5224 /* Use the global session count for the temporary snapshot. */
5225 tmp_output->nb_snapshot = session->snapshot.nb_snapshot;
5226
5227 /* Use the global datetime */
5228 memcpy(tmp_output->datetime, datetime, sizeof(datetime));
5229 cmd_ret = snapshot_record(session, tmp_output, wait);
5230 if (cmd_ret != LTTNG_OK) {
5231 goto error;
5232 }
5233 snapshot_success = 1;
5234 } else {
5235 struct snapshot_output *sout;
5236 struct lttng_ht_iter iter;
5237
5238 rcu_read_lock();
5239 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
5240 &iter.iter, sout, node.node) {
5241 struct snapshot_output output_copy;
5242
5243 /*
5244 * Make a local copy of the output and override output
5245 * parameters with those provided as part of the
5246 * command.
5247 */
5248 memcpy(&output_copy, sout, sizeof(output_copy));
5249
5250 if (output->max_size != (uint64_t) -1ULL) {
5251 output_copy.max_size = output->max_size;
5252 }
5253
5254 output_copy.nb_snapshot = session->snapshot.nb_snapshot;
5255 memcpy(output_copy.datetime, datetime,
5256 sizeof(datetime));
5257
5258 /* Use temporary name. */
5259 if (*output->name != '\0') {
5260 if (lttng_strncpy(output_copy.name,
5261 output->name,
5262 sizeof(output_copy.name))) {
5263 cmd_ret = LTTNG_ERR_INVALID;
5264 rcu_read_unlock();
5265 goto error;
5266 }
5267 }
5268
5269 cmd_ret = snapshot_record(session, &output_copy, wait);
5270 if (cmd_ret != LTTNG_OK) {
5271 rcu_read_unlock();
5272 goto error;
5273 }
5274 snapshot_success = 1;
5275 }
5276 rcu_read_unlock();
5277 }
5278
5279 if (snapshot_success) {
5280 session->snapshot.nb_snapshot++;
5281 } else {
5282 cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
5283 }
5284
5285 error:
5286 if (tmp_output) {
5287 snapshot_output_destroy(tmp_output);
5288 }
5289 return cmd_ret;
5290 }
5291
5292 /*
5293 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
5294 */
5295 int cmd_set_session_shm_path(struct ltt_session *session,
5296 const char *shm_path)
5297 {
5298 /* Safety net */
5299 assert(session);
5300
5301 /*
5302 * Can only set shm path before session is started.
5303 */
5304 if (session->has_been_started) {
5305 return LTTNG_ERR_SESSION_STARTED;
5306 }
5307
5308 strncpy(session->shm_path, shm_path,
5309 sizeof(session->shm_path));
5310 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
5311
5312 return LTTNG_OK;
5313 }
5314
5315 /*
5316 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
5317 *
5318 * Ask the consumer to rotate the session output directory.
5319 * The session lock must be held.
5320 *
5321 * Returns LTTNG_OK on success or else a negative LTTng error code.
5322 */
5323 int cmd_rotate_session(struct ltt_session *session,
5324 struct lttng_rotate_session_return *rotate_return,
5325 bool quiet_rotation,
5326 enum lttng_trace_chunk_command_type command)
5327 {
5328 int ret;
5329 uint64_t ongoing_rotation_chunk_id;
5330 enum lttng_error_code cmd_ret = LTTNG_OK;
5331 struct lttng_trace_chunk *chunk_being_archived = NULL;
5332 struct lttng_trace_chunk *new_trace_chunk = NULL;
5333 enum lttng_trace_chunk_status chunk_status;
5334 bool failed_to_rotate = false;
5335 enum lttng_error_code rotation_fail_code = LTTNG_OK;
5336
5337 assert(session);
5338
5339 if (!session->has_been_started) {
5340 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
5341 goto end;
5342 }
5343
5344 /*
5345 * Explicit rotation is not supported for live sessions.
5346 * However, live sessions can perform a quiet rotation on
5347 * destroy.
5348 * Rotation is not supported for snapshot traces (no output).
5349 */
5350 if ((!quiet_rotation && session->live_timer) ||
5351 !session->output_traces) {
5352 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5353 goto end;
5354 }
5355
5356 /* Unsupported feature in lttng-relayd before 2.11. */
5357 if (!quiet_rotation && session->consumer->type == CONSUMER_DST_NET &&
5358 (session->consumer->relay_major_version == 2 &&
5359 session->consumer->relay_minor_version < 11)) {
5360 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
5361 goto end;
5362 }
5363
5364 /* Unsupported feature in lttng-modules before 2.8 (lack of sequence number). */
5365 if (session->kernel_session && !kernel_supports_ring_buffer_packet_sequence_number()) {
5366 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL;
5367 goto end;
5368 }
5369
5370 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
5371 DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
5372 session->name);
5373 cmd_ret = LTTNG_ERR_ROTATION_PENDING;
5374 goto end;
5375 }
5376
5377 /*
5378 * After a stop, we only allow one rotation to occur, the other ones are
5379 * useless until a new start.
5380 */
5381 if (session->rotated_after_last_stop) {
5382 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
5383 session->name);
5384 cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
5385 goto end;
5386 }
5387
5388 /*
5389 * After a stop followed by a clear, disallow following rotations a they would
5390 * generate empty chunks.
5391 */
5392 if (session->cleared_after_last_stop) {
5393 DBG("Session \"%s\" was already cleared after stop, refusing rotation",
5394 session->name);
5395 cmd_ret = LTTNG_ERR_ROTATION_AFTER_STOP_CLEAR;
5396 goto end;
5397 }
5398
5399 if (session->active) {
5400 new_trace_chunk = session_create_new_trace_chunk(session, NULL,
5401 NULL, NULL);
5402 if (!new_trace_chunk) {
5403 cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
5404 goto error;
5405 }
5406 }
5407
5408 /*
5409 * The current trace chunk becomes the chunk being archived.
5410 *
5411 * After this point, "chunk_being_archived" must absolutely
5412 * be closed on the consumer(s), otherwise it will never be
5413 * cleaned-up, which will result in a leak.
5414 */
5415 ret = session_set_trace_chunk(session, new_trace_chunk,
5416 &chunk_being_archived);
5417 if (ret) {
5418 cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
5419 goto error;
5420 }
5421
5422 if (session->kernel_session) {
5423 cmd_ret = kernel_rotate_session(session);
5424 if (cmd_ret != LTTNG_OK) {
5425 failed_to_rotate = true;
5426 rotation_fail_code = cmd_ret;
5427 }
5428 }
5429 if (session->ust_session) {
5430 cmd_ret = ust_app_rotate_session(session);
5431 if (cmd_ret != LTTNG_OK) {
5432 failed_to_rotate = true;
5433 rotation_fail_code = cmd_ret;
5434 }
5435 }
5436
5437 if (!session->active) {
5438 session->rotated_after_last_stop = true;
5439 }
5440
5441 if (!chunk_being_archived) {
5442 DBG("Rotating session \"%s\" from a \"NULL\" trace chunk to a new trace chunk, skipping completion check",
5443 session->name);
5444 if (failed_to_rotate) {
5445 cmd_ret = rotation_fail_code;
5446 goto error;
5447 }
5448 cmd_ret = LTTNG_OK;
5449 goto end;
5450 }
5451
5452 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
5453 chunk_status = lttng_trace_chunk_get_id(chunk_being_archived,
5454 &ongoing_rotation_chunk_id);
5455 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5456
5457 ret = session_close_trace_chunk(session, chunk_being_archived,
5458 command, session->last_chunk_path);
5459 if (ret) {
5460 cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5461 goto error;
5462 }
5463
5464 if (failed_to_rotate) {
5465 cmd_ret = rotation_fail_code;
5466 goto error;
5467 }
5468
5469 session->quiet_rotation = quiet_rotation;
5470 ret = timer_session_rotation_pending_check_start(session,
5471 DEFAULT_ROTATE_PENDING_TIMER);
5472 if (ret) {
5473 cmd_ret = LTTNG_ERR_UNK;
5474 goto error;
5475 }
5476
5477 if (rotate_return) {
5478 rotate_return->rotation_id = ongoing_rotation_chunk_id;
5479 }
5480
5481 session->chunk_being_archived = chunk_being_archived;
5482 chunk_being_archived = NULL;
5483 if (!quiet_rotation) {
5484 ret = notification_thread_command_session_rotation_ongoing(
5485 the_notification_thread_handle, session->name,
5486 session->uid, session->gid,
5487 ongoing_rotation_chunk_id);
5488 if (ret != LTTNG_OK) {
5489 ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
5490 session->name);
5491 cmd_ret = ret;
5492 }
5493 }
5494
5495 DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
5496 session->name, ongoing_rotation_chunk_id);
5497 end:
5498 lttng_trace_chunk_put(new_trace_chunk);
5499 lttng_trace_chunk_put(chunk_being_archived);
5500 ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
5501 return ret;
5502 error:
5503 if (session_reset_rotation_state(session,
5504 LTTNG_ROTATION_STATE_ERROR)) {
5505 ERR("Failed to reset rotation state of session \"%s\"",
5506 session->name);
5507 }
5508 goto end;
5509 }
5510
5511 /*
5512 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
5513 *
5514 * Check if the session has finished its rotation.
5515 *
5516 * Return LTTNG_OK on success or else an LTTNG_ERR code.
5517 */
5518 int cmd_rotate_get_info(struct ltt_session *session,
5519 struct lttng_rotation_get_info_return *info_return,
5520 uint64_t rotation_id)
5521 {
5522 enum lttng_error_code cmd_ret = LTTNG_OK;
5523 enum lttng_rotation_state rotation_state;
5524
5525 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
5526 session->most_recent_chunk_id.value);
5527
5528 if (session->chunk_being_archived) {
5529 enum lttng_trace_chunk_status chunk_status;
5530 uint64_t chunk_id;
5531
5532 chunk_status = lttng_trace_chunk_get_id(
5533 session->chunk_being_archived,
5534 &chunk_id);
5535 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5536
5537 rotation_state = rotation_id == chunk_id ?
5538 LTTNG_ROTATION_STATE_ONGOING :
5539 LTTNG_ROTATION_STATE_EXPIRED;
5540 } else {
5541 if (session->last_archived_chunk_id.is_set &&
5542 rotation_id != session->last_archived_chunk_id.value) {
5543 rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
5544 } else {
5545 rotation_state = session->rotation_state;
5546 }
5547 }
5548
5549 switch (rotation_state) {
5550 case LTTNG_ROTATION_STATE_NO_ROTATION:
5551 DBG("Reporting that no rotation has occurred within the lifetime of session \"%s\"",
5552 session->name);
5553 goto end;
5554 case LTTNG_ROTATION_STATE_EXPIRED:
5555 DBG("Reporting that the rotation state of rotation id %" PRIu64 " of session \"%s\" has expired",
5556 rotation_id, session->name);
5557 break;
5558 case LTTNG_ROTATION_STATE_ONGOING:
5559 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
5560 rotation_id, session->name);
5561 break;
5562 case LTTNG_ROTATION_STATE_COMPLETED:
5563 {
5564 int fmt_ret;
5565 char *chunk_path;
5566 char *current_tracing_path_reply;
5567 size_t current_tracing_path_reply_len;
5568
5569 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
5570 rotation_id, session->name);
5571
5572 switch (session_get_consumer_destination_type(session)) {
5573 case CONSUMER_DST_LOCAL:
5574 current_tracing_path_reply =
5575 info_return->location.local.absolute_path;
5576 current_tracing_path_reply_len =
5577 sizeof(info_return->location.local.absolute_path);
5578 info_return->location_type =
5579 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
5580 fmt_ret = asprintf(&chunk_path,
5581 "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
5582 session_get_base_path(session),
5583 session->last_archived_chunk_name);
5584 if (fmt_ret == -1) {
5585 PERROR("Failed to format the path of the last archived trace chunk");
5586 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5587 cmd_ret = LTTNG_ERR_UNK;
5588 goto end;
5589 }
5590 break;
5591 case CONSUMER_DST_NET:
5592 {
5593 uint16_t ctrl_port, data_port;
5594
5595 current_tracing_path_reply =
5596 info_return->location.relay.relative_path;
5597 current_tracing_path_reply_len =
5598 sizeof(info_return->location.relay.relative_path);
5599 /* Currently the only supported relay protocol. */
5600 info_return->location.relay.protocol =
5601 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
5602
5603 fmt_ret = lttng_strncpy(info_return->location.relay.host,
5604 session_get_net_consumer_hostname(session),
5605 sizeof(info_return->location.relay.host));
5606 if (fmt_ret) {
5607 ERR("Failed to copy host name to rotate_get_info reply");
5608 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5609 cmd_ret = LTTNG_ERR_SET_URL;
5610 goto end;
5611 }
5612
5613 session_get_net_consumer_ports(session, &ctrl_port, &data_port);
5614 info_return->location.relay.ports.control = ctrl_port;
5615 info_return->location.relay.ports.data = data_port;
5616 info_return->location_type =
5617 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
5618 chunk_path = strdup(session->last_chunk_path);
5619 if (!chunk_path) {
5620 ERR("Failed to allocate the path of the last archived trace chunk");
5621 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5622 cmd_ret = LTTNG_ERR_UNK;
5623 goto end;
5624 }
5625 break;
5626 }
5627 default:
5628 abort();
5629 }
5630
5631 fmt_ret = lttng_strncpy(current_tracing_path_reply,
5632 chunk_path, current_tracing_path_reply_len);
5633 free(chunk_path);
5634 if (fmt_ret) {
5635 ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
5636 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5637 cmd_ret = LTTNG_ERR_UNK;
5638 goto end;
5639 }
5640
5641 break;
5642 }
5643 case LTTNG_ROTATION_STATE_ERROR:
5644 DBG("Reporting that an error occurred during rotation %" PRIu64 " of session \"%s\"",
5645 rotation_id, session->name);
5646 break;
5647 default:
5648 abort();
5649 }
5650
5651 cmd_ret = LTTNG_OK;
5652 end:
5653 info_return->status = (int32_t) rotation_state;
5654 return cmd_ret;
5655 }
5656
5657 /*
5658 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
5659 *
5660 * Configure the automatic rotation parameters.
5661 * 'activate' to true means activate the rotation schedule type with 'new_value'.
5662 * 'activate' to false means deactivate the rotation schedule and validate that
5663 * 'new_value' has the same value as the currently active value.
5664 *
5665 * Return LTTNG_OK on success or else a positive LTTNG_ERR code.
5666 */
5667 int cmd_rotation_set_schedule(struct ltt_session *session,
5668 bool activate, enum lttng_rotation_schedule_type schedule_type,
5669 uint64_t new_value,
5670 struct notification_thread_handle *notification_thread_handle)
5671 {
5672 int ret;
5673 uint64_t *parameter_value;
5674
5675 assert(session);
5676
5677 DBG("Cmd rotate set schedule session %s", session->name);
5678
5679 if (session->live_timer || !session->output_traces) {
5680 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
5681 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5682 goto end;
5683 }
5684
5685 switch (schedule_type) {
5686 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5687 parameter_value = &session->rotate_size;
5688 break;
5689 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5690 parameter_value = &session->rotate_timer_period;
5691 if (new_value >= UINT_MAX) {
5692 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
5693 new_value, UINT_MAX);
5694 ret = LTTNG_ERR_INVALID;
5695 goto end;
5696 }
5697 break;
5698 default:
5699 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
5700 ret = LTTNG_ERR_INVALID;
5701 goto end;
5702 }
5703
5704 /* Improper use of the API. */
5705 if (new_value == -1ULL) {
5706 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
5707 ret = LTTNG_ERR_INVALID;
5708 goto end;
5709 }
5710
5711 /*
5712 * As indicated in struct ltt_session's comments, a value of == 0 means
5713 * this schedule rotation type is not in use.
5714 *
5715 * Reject the command if we were asked to activate a schedule that was
5716 * already active.
5717 */
5718 if (activate && *parameter_value != 0) {
5719 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
5720 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
5721 goto end;
5722 }
5723
5724 /*
5725 * Reject the command if we were asked to deactivate a schedule that was
5726 * not active.
5727 */
5728 if (!activate && *parameter_value == 0) {
5729 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
5730 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5731 goto end;
5732 }
5733
5734 /*
5735 * Reject the command if we were asked to deactivate a schedule that
5736 * doesn't exist.
5737 */
5738 if (!activate && *parameter_value != new_value) {
5739 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
5740 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5741 goto end;
5742 }
5743
5744 *parameter_value = activate ? new_value : 0;
5745
5746 switch (schedule_type) {
5747 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5748 if (activate && session->active) {
5749 /*
5750 * Only start the timer if the session is active,
5751 * otherwise it will be started when the session starts.
5752 */
5753 ret = timer_session_rotation_schedule_timer_start(
5754 session, new_value);
5755 if (ret) {
5756 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
5757 ret = LTTNG_ERR_UNK;
5758 goto end;
5759 }
5760 } else {
5761 ret = timer_session_rotation_schedule_timer_stop(
5762 session);
5763 if (ret) {
5764 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
5765 ret = LTTNG_ERR_UNK;
5766 goto end;
5767 }
5768 }
5769 break;
5770 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5771 if (activate) {
5772 ret = subscribe_session_consumed_size_rotation(session,
5773 new_value, notification_thread_handle);
5774 if (ret) {
5775 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
5776 ret = LTTNG_ERR_UNK;
5777 goto end;
5778 }
5779 } else {
5780 ret = unsubscribe_session_consumed_size_rotation(session,
5781 notification_thread_handle);
5782 if (ret) {
5783 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
5784 ret = LTTNG_ERR_UNK;
5785 goto end;
5786 }
5787
5788 }
5789 break;
5790 default:
5791 /* Would have been caught before. */
5792 abort();
5793 }
5794
5795 ret = LTTNG_OK;
5796
5797 goto end;
5798
5799 end:
5800 return ret;
5801 }
5802
5803 /* Wait for a given path to be removed before continuing. */
5804 static enum lttng_error_code wait_on_path(void *path_data)
5805 {
5806 const char *shm_path = path_data;
5807
5808 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5809 shm_path);
5810 while (true) {
5811 int ret;
5812 struct stat st;
5813
5814 ret = stat(shm_path, &st);
5815 if (ret) {
5816 if (errno != ENOENT) {
5817 PERROR("stat() returned an error while checking for the existence of the shm path");
5818 } else {
5819 DBG("shm path no longer exists, completing the destruction of session");
5820 }
5821 break;
5822 } else {
5823 if (!S_ISDIR(st.st_mode)) {
5824 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5825 shm_path);
5826 break;
5827 }
5828 }
5829 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
5830 }
5831 return LTTNG_OK;
5832 }
5833
5834 /*
5835 * Returns a pointer to a handler to run on completion of a command.
5836 * Returns NULL if no handler has to be run for the last command executed.
5837 */
5838 const struct cmd_completion_handler *cmd_pop_completion_handler(void)
5839 {
5840 struct cmd_completion_handler *handler = current_completion_handler;
5841
5842 current_completion_handler = NULL;
5843 return handler;
5844 }
5845
5846 /*
5847 * Init command subsystem.
5848 */
5849 void cmd_init(void)
5850 {
5851 /*
5852 * Set network sequence index to 1 for streams to match a relayd
5853 * socket on the consumer side.
5854 */
5855 pthread_mutex_lock(&relayd_net_seq_idx_lock);
5856 relayd_net_seq_idx = 1;
5857 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
5858
5859 DBG("Command subsystem initialized");
5860 }
LTTng 2.0 tools and control repository
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