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Fix: liblttng-ctl comm: lttng_event is not packed
[lttng-tools.git] / src / bin / lttng-sessiond / cmd.cpp
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 <algorithm>
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/relayd/relayd.h>
25 #include <common/sessiond-comm/sessiond-comm.h>
26 #include <common/string-utils/string-utils.h>
27 #include <common/trace-chunk.h>
28 #include <common/utils.h>
29
30 #include <lttng/action/action.h>
31 #include <lttng/action/action-internal.h>
32 #include <lttng/channel-internal.h>
33 #include <lttng/channel.h>
34 #include <lttng/condition/condition.h>
35 #include <lttng/error-query-internal.h>
36 #include <lttng/event-internal.h>
37 #include <lttng/location-internal.h>
38 #include <lttng/rotate-internal.h>
39 #include <lttng/session-descriptor-internal.h>
40 #include <lttng/session-internal.h>
41 #include <lttng/trigger/trigger-internal.h>
42 #include <lttng/userspace-probe-internal.h>
43
44 #include "agent-thread.h"
45 #include "agent.h"
46 #include "buffer-registry.h"
47 #include "channel.h"
48 #include "cmd.h"
49 #include "consumer.h"
50 #include "event-notifier-error-accounting.h"
51 #include "event.h"
52 #include "health-sessiond.h"
53 #include "kernel-consumer.h"
54 #include "kernel.h"
55 #include "lttng-sessiond.h"
56 #include "lttng-syscall.h"
57 #include "notification-thread-commands.h"
58 #include "notification-thread.h"
59 #include "rotate.h"
60 #include "rotation-thread.h"
61 #include "session.h"
62 #include "timer.h"
63 #include "tracker.h"
64 #include "utils.h"
65
66 /* Sleep for 100ms between each check for the shm path's deletion. */
67 #define SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US 100000
68
69 struct cmd_destroy_session_reply_context {
70 int reply_sock_fd;
71 bool implicit_rotation_on_destroy;
72 /*
73 * Indicates whether or not an error occurred while launching the
74 * destruction of a session.
75 */
76 enum lttng_error_code destruction_status;
77 };
78
79 static enum lttng_error_code wait_on_path(void *path);
80
81 /*
82 * Command completion handler that is used by the destroy command
83 * when a session that has a non-default shm_path is being destroyed.
84 *
85 * See comment in cmd_destroy_session() for the rationale.
86 */
87 static struct destroy_completion_handler {
88 struct cmd_completion_handler handler;
89 char shm_path[member_sizeof(struct ltt_session, shm_path)];
90 } destroy_completion_handler = {
91 .handler = {
92 .run = wait_on_path,
93 .data = destroy_completion_handler.shm_path
94 },
95 .shm_path = { 0 },
96 };
97
98 static struct cmd_completion_handler *current_completion_handler;
99
100 /*
101 * Used to keep a unique index for each relayd socket created where this value
102 * is associated with streams on the consumer so it can match the right relayd
103 * to send to. It must be accessed with the relayd_net_seq_idx_lock
104 * held.
105 */
106 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
107 static uint64_t relayd_net_seq_idx;
108
109 static int validate_ust_event_name(const char *);
110 static int cmd_enable_event_internal(struct ltt_session *session,
111 const struct lttng_domain *domain,
112 char *channel_name, struct lttng_event *event,
113 char *filter_expression,
114 struct lttng_bytecode *filter,
115 struct lttng_event_exclusion *exclusion,
116 int wpipe);
117 static int cmd_enable_channel_internal(struct ltt_session *session,
118 const struct lttng_domain *domain,
119 const struct lttng_channel *_attr,
120 int wpipe);
121
122 /*
123 * Create a session path used by list_lttng_sessions for the case that the
124 * session consumer is on the network.
125 */
126 static int build_network_session_path(char *dst, size_t size,
127 struct ltt_session *session)
128 {
129 int ret, kdata_port, udata_port;
130 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
131 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
132
133 LTTNG_ASSERT(session);
134 LTTNG_ASSERT(dst);
135
136 memset(tmp_urls, 0, sizeof(tmp_urls));
137 memset(tmp_uurl, 0, sizeof(tmp_uurl));
138
139 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
140
141 if (session->kernel_session && session->kernel_session->consumer) {
142 kuri = &session->kernel_session->consumer->dst.net.control;
143 kdata_port = session->kernel_session->consumer->dst.net.data.port;
144 }
145
146 if (session->ust_session && session->ust_session->consumer) {
147 uuri = &session->ust_session->consumer->dst.net.control;
148 udata_port = session->ust_session->consumer->dst.net.data.port;
149 }
150
151 if (uuri == NULL && kuri == NULL) {
152 uri = &session->consumer->dst.net.control;
153 kdata_port = session->consumer->dst.net.data.port;
154 } else if (kuri && uuri) {
155 ret = uri_compare(kuri, uuri);
156 if (ret) {
157 /* Not Equal */
158 uri = kuri;
159 /* Build uuri URL string */
160 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
161 if (ret < 0) {
162 goto error;
163 }
164 } else {
165 uri = kuri;
166 }
167 } else if (kuri && uuri == NULL) {
168 uri = kuri;
169 } else if (uuri && kuri == NULL) {
170 uri = uuri;
171 }
172
173 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
174 if (ret < 0) {
175 goto error;
176 }
177
178 /*
179 * Do we have a UST url set. If yes, this means we have both kernel and UST
180 * to print.
181 */
182 if (*tmp_uurl != '\0') {
183 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
184 tmp_urls, kdata_port, tmp_uurl, udata_port);
185 } else {
186 int dport;
187 if (kuri || (!kuri && !uuri)) {
188 dport = kdata_port;
189 } else {
190 /* No kernel URI, use the UST port. */
191 dport = udata_port;
192 }
193 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
194 }
195
196 error:
197 return ret;
198 }
199
200 /*
201 * Get run-time attributes if the session has been started (discarded events,
202 * lost packets).
203 */
204 static int get_kernel_runtime_stats(struct ltt_session *session,
205 struct ltt_kernel_channel *kchan, uint64_t *discarded_events,
206 uint64_t *lost_packets)
207 {
208 int ret;
209
210 if (!session->has_been_started) {
211 ret = 0;
212 *discarded_events = 0;
213 *lost_packets = 0;
214 goto end;
215 }
216
217 ret = consumer_get_discarded_events(session->id, kchan->key,
218 session->kernel_session->consumer,
219 discarded_events);
220 if (ret < 0) {
221 goto end;
222 }
223
224 ret = consumer_get_lost_packets(session->id, kchan->key,
225 session->kernel_session->consumer,
226 lost_packets);
227 if (ret < 0) {
228 goto end;
229 }
230
231 end:
232 return ret;
233 }
234
235 /*
236 * Get run-time attributes if the session has been started (discarded events,
237 * lost packets).
238 */
239 static int get_ust_runtime_stats(struct ltt_session *session,
240 struct ltt_ust_channel *uchan, uint64_t *discarded_events,
241 uint64_t *lost_packets)
242 {
243 int ret;
244 struct ltt_ust_session *usess;
245
246 if (!discarded_events || !lost_packets) {
247 ret = -1;
248 goto end;
249 }
250
251 usess = session->ust_session;
252 LTTNG_ASSERT(discarded_events);
253 LTTNG_ASSERT(lost_packets);
254
255 if (!usess || !session->has_been_started) {
256 *discarded_events = 0;
257 *lost_packets = 0;
258 ret = 0;
259 goto end;
260 }
261
262 if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
263 ret = ust_app_uid_get_channel_runtime_stats(usess->id,
264 &usess->buffer_reg_uid_list,
265 usess->consumer, uchan->id,
266 uchan->attr.overwrite,
267 discarded_events,
268 lost_packets);
269 } else if (usess->buffer_type == LTTNG_BUFFER_PER_PID) {
270 ret = ust_app_pid_get_channel_runtime_stats(usess,
271 uchan, usess->consumer,
272 uchan->attr.overwrite,
273 discarded_events,
274 lost_packets);
275 if (ret < 0) {
276 goto end;
277 }
278 *discarded_events += uchan->per_pid_closed_app_discarded;
279 *lost_packets += uchan->per_pid_closed_app_lost;
280 } else {
281 ERR("Unsupported buffer type");
282 abort();
283 ret = -1;
284 goto end;
285 }
286
287 end:
288 return ret;
289 }
290
291 /*
292 * Create a list of agent domain events.
293 *
294 * Return number of events in list on success or else a negative value.
295 */
296 static enum lttng_error_code list_lttng_agent_events(
297 struct agent *agt, struct lttng_payload *reply_payload,
298 unsigned int *nb_events)
299 {
300 enum lttng_error_code ret_code;
301 int ret = 0;
302 unsigned int local_nb_events = 0;
303 struct agent_event *event;
304 struct lttng_ht_iter iter;
305 unsigned long agent_event_count;
306
307 assert(agt);
308 assert(reply_payload);
309
310 DBG3("Listing agent events");
311
312 rcu_read_lock();
313 agent_event_count = lttng_ht_get_count(agt->events);
314 if (agent_event_count == 0) {
315 /* Early exit. */
316 goto end;
317 }
318
319 if (agent_event_count > UINT_MAX) {
320 ret_code = LTTNG_ERR_OVERFLOW;
321 goto error;
322 }
323
324 local_nb_events = (unsigned int) agent_event_count;
325
326 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
327 struct lttng_event *tmp_event = lttng_event_create();
328
329 if (!tmp_event) {
330 ret_code = LTTNG_ERR_NOMEM;
331 goto error;
332 }
333
334 if (lttng_strncpy(tmp_event->name, event->name, sizeof(tmp_event->name))) {
335 lttng_event_destroy(tmp_event);
336 ret_code = LTTNG_ERR_FATAL;
337 goto error;
338 }
339
340 tmp_event->name[sizeof(tmp_event->name) - 1] = '\0';
341 tmp_event->enabled = !!event->enabled_count;
342 tmp_event->loglevel = event->loglevel_value;
343 tmp_event->loglevel_type = event->loglevel_type;
344
345 ret = lttng_event_serialize(tmp_event, 0, NULL,
346 event->filter_expression, 0, NULL, reply_payload);
347 lttng_event_destroy(tmp_event);
348 if (ret) {
349 ret_code = LTTNG_ERR_FATAL;
350 goto error;
351 }
352 }
353
354 end:
355 ret_code = LTTNG_OK;
356 *nb_events = local_nb_events;
357 error:
358 rcu_read_unlock();
359 return ret_code;
360 }
361
362 /*
363 * Create a list of ust global domain events.
364 */
365 static enum lttng_error_code list_lttng_ust_global_events(char *channel_name,
366 struct ltt_ust_domain_global *ust_global,
367 struct lttng_payload *reply_payload,
368 unsigned int *nb_events)
369 {
370 enum lttng_error_code ret_code;
371 int ret;
372 struct lttng_ht_iter iter;
373 struct lttng_ht_node_str *node;
374 struct ltt_ust_channel *uchan;
375 struct ltt_ust_event *uevent;
376 unsigned long channel_event_count;
377 unsigned int local_nb_events = 0;
378
379 assert(reply_payload);
380 assert(nb_events);
381
382 DBG("Listing UST global events for channel %s", channel_name);
383
384 rcu_read_lock();
385
386 lttng_ht_lookup(ust_global->channels, (void *) channel_name, &iter);
387 node = lttng_ht_iter_get_node_str(&iter);
388 if (node == NULL) {
389 ret_code = LTTNG_ERR_UST_CHAN_NOT_FOUND;
390 goto end;
391 }
392
393 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
394
395 channel_event_count = lttng_ht_get_count(uchan->events);
396 if (channel_event_count == 0) {
397 /* Early exit. */
398 ret_code = LTTNG_OK;
399 goto end;
400 }
401
402 if (channel_event_count > UINT_MAX) {
403 ret_code = LTTNG_ERR_OVERFLOW;
404 goto error;
405 }
406
407 local_nb_events = (unsigned int) channel_event_count;
408
409 DBG3("Listing UST global %d events", *nb_events);
410
411 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
412 struct lttng_event *tmp_event = NULL;
413
414 if (uevent->internal) {
415 /* This event should remain hidden from clients */
416 local_nb_events--;
417 continue;
418 }
419
420 tmp_event = lttng_event_create();
421 if (!tmp_event) {
422 ret_code = LTTNG_ERR_NOMEM;
423 goto end;
424 }
425
426 if (lttng_strncpy(tmp_event->name, uevent->attr.name,
427 LTTNG_SYMBOL_NAME_LEN)) {
428 ret_code = LTTNG_ERR_FATAL;
429 lttng_event_destroy(tmp_event);
430 goto end;
431 }
432
433 tmp_event->name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
434 tmp_event->enabled = uevent->enabled;
435
436 switch (uevent->attr.instrumentation) {
437 case LTTNG_UST_ABI_TRACEPOINT:
438 tmp_event->type = LTTNG_EVENT_TRACEPOINT;
439 break;
440 case LTTNG_UST_ABI_PROBE:
441 tmp_event->type = LTTNG_EVENT_PROBE;
442 break;
443 case LTTNG_UST_ABI_FUNCTION:
444 tmp_event->type = LTTNG_EVENT_FUNCTION;
445 break;
446 }
447
448 tmp_event->loglevel = uevent->attr.loglevel;
449 switch (uevent->attr.loglevel_type) {
450 case LTTNG_UST_ABI_LOGLEVEL_ALL:
451 tmp_event->loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
452 break;
453 case LTTNG_UST_ABI_LOGLEVEL_RANGE:
454 tmp_event->loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
455 break;
456 case LTTNG_UST_ABI_LOGLEVEL_SINGLE:
457 tmp_event->loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
458 break;
459 }
460 if (uevent->filter) {
461 tmp_event->filter = 1;
462 }
463 if (uevent->exclusion) {
464 tmp_event->exclusion = 1;
465 }
466
467 /*
468 * We do not care about the filter bytecode and the fd from the
469 * userspace_probe_location.
470 */
471 ret = lttng_event_serialize(tmp_event, uevent->exclusion ? uevent->exclusion->count : 0,
472 uevent->exclusion ? (char **) uevent->exclusion ->names : NULL,
473 uevent->filter_expression, 0, NULL, reply_payload);
474 lttng_event_destroy(tmp_event);
475 if (ret) {
476 ret_code = LTTNG_ERR_FATAL;
477 goto error;
478 }
479 }
480
481 end:
482 /* nb_events is already set at this point. */
483 ret_code = LTTNG_OK;
484 *nb_events = local_nb_events;
485 error:
486 rcu_read_unlock();
487 return ret_code;
488 }
489
490 /*
491 * Fill lttng_event array of all kernel events in the channel.
492 */
493 static enum lttng_error_code list_lttng_kernel_events(char *channel_name,
494 struct ltt_kernel_session *kernel_session,
495 struct lttng_payload *reply_payload,
496 unsigned int *nb_events)
497 {
498 enum lttng_error_code ret_code;
499 int ret;
500 struct ltt_kernel_event *event;
501 struct ltt_kernel_channel *kchan;
502
503 assert(reply_payload);
504
505 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
506 if (kchan == NULL) {
507 ret_code = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
508 goto end;
509 }
510
511 *nb_events = kchan->event_count;
512
513 DBG("Listing events for channel %s", kchan->channel->name);
514
515 if (*nb_events == 0) {
516 ret_code = LTTNG_OK;
517 goto end;
518 }
519
520 /* Kernel channels */
521 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
522 struct lttng_event *tmp_event = lttng_event_create();
523
524 if (!tmp_event) {
525 ret_code = LTTNG_ERR_NOMEM;
526 goto end;
527 }
528
529 if (lttng_strncpy(tmp_event->name, event->event->name, LTTNG_SYMBOL_NAME_LEN)) {
530 lttng_event_destroy(tmp_event);
531 ret_code = LTTNG_ERR_FATAL;
532 goto end;
533
534 }
535
536 tmp_event->name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
537 tmp_event->enabled = event->enabled;
538 tmp_event->filter = (unsigned char) !!event->filter_expression;
539
540 switch (event->event->instrumentation) {
541 case LTTNG_KERNEL_ABI_TRACEPOINT:
542 tmp_event->type = LTTNG_EVENT_TRACEPOINT;
543 break;
544 case LTTNG_KERNEL_ABI_KRETPROBE:
545 tmp_event->type = LTTNG_EVENT_FUNCTION;
546 memcpy(&tmp_event->attr.probe, &event->event->u.kprobe,
547 sizeof(struct lttng_kernel_abi_kprobe));
548 break;
549 case LTTNG_KERNEL_ABI_KPROBE:
550 tmp_event->type = LTTNG_EVENT_PROBE;
551 memcpy(&tmp_event->attr.probe, &event->event->u.kprobe,
552 sizeof(struct lttng_kernel_abi_kprobe));
553 break;
554 case LTTNG_KERNEL_ABI_UPROBE:
555 tmp_event->type = LTTNG_EVENT_USERSPACE_PROBE;
556 break;
557 case LTTNG_KERNEL_ABI_FUNCTION:
558 tmp_event->type = LTTNG_EVENT_FUNCTION;
559 memcpy(&(tmp_event->attr.ftrace), &event->event->u.ftrace,
560 sizeof(struct lttng_kernel_abi_function));
561 break;
562 case LTTNG_KERNEL_ABI_NOOP:
563 tmp_event->type = LTTNG_EVENT_NOOP;
564 break;
565 case LTTNG_KERNEL_ABI_SYSCALL:
566 tmp_event->type = LTTNG_EVENT_SYSCALL;
567 break;
568 case LTTNG_KERNEL_ABI_ALL:
569 /* fall-through. */
570 default:
571 abort();
572 break;
573 }
574
575 if (event->userspace_probe_location) {
576 struct lttng_userspace_probe_location *location_copy =
577 lttng_userspace_probe_location_copy(
578 event->userspace_probe_location);
579
580 if (!location_copy) {
581 lttng_event_destroy(tmp_event);
582 ret_code = LTTNG_ERR_NOMEM;
583 goto end;
584 }
585
586 ret = lttng_event_set_userspace_probe_location(
587 tmp_event, location_copy);
588 if (ret) {
589 lttng_event_destroy(tmp_event);
590 lttng_userspace_probe_location_destroy(
591 location_copy);
592 ret_code = LTTNG_ERR_INVALID;
593 goto end;
594 }
595 }
596
597 ret = lttng_event_serialize(tmp_event, 0, NULL,
598 event->filter_expression, 0, NULL, reply_payload);
599 lttng_event_destroy(tmp_event);
600 if (ret) {
601 ret_code = LTTNG_ERR_FATAL;
602 goto end;
603 }
604 }
605
606 ret_code = LTTNG_OK;
607 end:
608 return ret_code;
609 }
610
611 /*
612 * Add URI so the consumer output object. Set the correct path depending on the
613 * domain adding the default trace directory.
614 */
615 static enum lttng_error_code add_uri_to_consumer(
616 const struct ltt_session *session,
617 struct consumer_output *consumer,
618 struct lttng_uri *uri, enum lttng_domain_type domain)
619 {
620 int ret;
621 enum lttng_error_code ret_code = LTTNG_OK;
622
623 LTTNG_ASSERT(uri);
624
625 if (consumer == NULL) {
626 DBG("No consumer detected. Don't add URI. Stopping.");
627 ret_code = LTTNG_ERR_NO_CONSUMER;
628 goto error;
629 }
630
631 switch (domain) {
632 case LTTNG_DOMAIN_KERNEL:
633 ret = lttng_strncpy(consumer->domain_subdir,
634 DEFAULT_KERNEL_TRACE_DIR,
635 sizeof(consumer->domain_subdir));
636 break;
637 case LTTNG_DOMAIN_UST:
638 ret = lttng_strncpy(consumer->domain_subdir,
639 DEFAULT_UST_TRACE_DIR,
640 sizeof(consumer->domain_subdir));
641 break;
642 default:
643 /*
644 * This case is possible is we try to add the URI to the global
645 * tracing session consumer object which in this case there is
646 * no subdir.
647 */
648 memset(consumer->domain_subdir, 0,
649 sizeof(consumer->domain_subdir));
650 ret = 0;
651 }
652 if (ret) {
653 ERR("Failed to initialize consumer output domain subdirectory");
654 ret_code = LTTNG_ERR_FATAL;
655 goto error;
656 }
657
658 switch (uri->dtype) {
659 case LTTNG_DST_IPV4:
660 case LTTNG_DST_IPV6:
661 DBG2("Setting network URI to consumer");
662
663 if (consumer->type == CONSUMER_DST_NET) {
664 if ((uri->stype == LTTNG_STREAM_CONTROL &&
665 consumer->dst.net.control_isset) ||
666 (uri->stype == LTTNG_STREAM_DATA &&
667 consumer->dst.net.data_isset)) {
668 ret_code = LTTNG_ERR_URL_EXIST;
669 goto error;
670 }
671 } else {
672 memset(&consumer->dst, 0, sizeof(consumer->dst));
673 }
674
675 /* Set URI into consumer output object */
676 ret = consumer_set_network_uri(session, consumer, uri);
677 if (ret < 0) {
678 ret_code = (lttng_error_code) -ret;
679 goto error;
680 } else if (ret == 1) {
681 /*
682 * URI was the same in the consumer so we do not append the subdir
683 * again so to not duplicate output dir.
684 */
685 ret_code = LTTNG_OK;
686 goto error;
687 }
688 break;
689 case LTTNG_DST_PATH:
690 if (*uri->dst.path != '/' || strstr(uri->dst.path, "../")) {
691 ret_code = LTTNG_ERR_INVALID;
692 goto error;
693 }
694 DBG2("Setting trace directory path from URI to %s",
695 uri->dst.path);
696 memset(&consumer->dst, 0, sizeof(consumer->dst));
697
698 ret = lttng_strncpy(consumer->dst.session_root_path,
699 uri->dst.path,
700 sizeof(consumer->dst.session_root_path));
701 if (ret) {
702 ret_code = LTTNG_ERR_FATAL;
703 goto error;
704 }
705 consumer->type = CONSUMER_DST_LOCAL;
706 break;
707 }
708
709 ret_code = LTTNG_OK;
710 error:
711 return ret_code;
712 }
713
714 /*
715 * Init tracing by creating trace directory and sending fds kernel consumer.
716 */
717 static int init_kernel_tracing(struct ltt_kernel_session *session)
718 {
719 int ret = 0;
720 struct lttng_ht_iter iter;
721 struct consumer_socket *socket;
722
723 LTTNG_ASSERT(session);
724
725 rcu_read_lock();
726
727 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
728 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
729 socket, node.node) {
730 pthread_mutex_lock(socket->lock);
731 ret = kernel_consumer_send_session(socket, session);
732 pthread_mutex_unlock(socket->lock);
733 if (ret < 0) {
734 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
735 goto error;
736 }
737 }
738 }
739
740 error:
741 rcu_read_unlock();
742 return ret;
743 }
744
745 /*
746 * Create a socket to the relayd using the URI.
747 *
748 * On success, the relayd_sock pointer is set to the created socket.
749 * Else, it remains untouched and an LTTng error code is returned.
750 */
751 static enum lttng_error_code create_connect_relayd(struct lttng_uri *uri,
752 struct lttcomm_relayd_sock **relayd_sock,
753 struct consumer_output *consumer)
754 {
755 int ret;
756 enum lttng_error_code status = LTTNG_OK;
757 struct lttcomm_relayd_sock *rsock;
758
759 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
760 RELAYD_VERSION_COMM_MINOR);
761 if (!rsock) {
762 status = LTTNG_ERR_FATAL;
763 goto error;
764 }
765
766 /*
767 * Connect to relayd so we can proceed with a session creation. This call
768 * can possibly block for an arbitrary amount of time to set the health
769 * state to be in poll execution.
770 */
771 health_poll_entry();
772 ret = relayd_connect(rsock);
773 health_poll_exit();
774 if (ret < 0) {
775 ERR("Unable to reach lttng-relayd");
776 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
777 goto free_sock;
778 }
779
780 /* Create socket for control stream. */
781 if (uri->stype == LTTNG_STREAM_CONTROL) {
782 uint64_t result_flags;
783
784 DBG3("Creating relayd stream socket from URI");
785
786 /* Check relayd version */
787 ret = relayd_version_check(rsock);
788 if (ret == LTTNG_ERR_RELAYD_VERSION_FAIL) {
789 status = LTTNG_ERR_RELAYD_VERSION_FAIL;
790 goto close_sock;
791 } else if (ret < 0) {
792 ERR("Unable to reach lttng-relayd");
793 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
794 goto close_sock;
795 }
796 consumer->relay_major_version = rsock->major;
797 consumer->relay_minor_version = rsock->minor;
798 ret = relayd_get_configuration(rsock, 0,
799 &result_flags);
800 if (ret < 0) {
801 ERR("Unable to get relayd configuration");
802 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
803 goto close_sock;
804 }
805 if (result_flags & LTTCOMM_RELAYD_CONFIGURATION_FLAG_CLEAR_ALLOWED) {
806 consumer->relay_allows_clear = true;
807 }
808 } else if (uri->stype == LTTNG_STREAM_DATA) {
809 DBG3("Creating relayd data socket from URI");
810 } else {
811 /* Command is not valid */
812 ERR("Relayd invalid stream type: %d", uri->stype);
813 status = LTTNG_ERR_INVALID;
814 goto close_sock;
815 }
816
817 *relayd_sock = rsock;
818
819 return status;
820
821 close_sock:
822 /* The returned value is not useful since we are on an error path. */
823 (void) relayd_close(rsock);
824 free_sock:
825 free(rsock);
826 error:
827 return status;
828 }
829
830 /*
831 * Connect to the relayd using URI and send the socket to the right consumer.
832 *
833 * The consumer socket lock must be held by the caller.
834 *
835 * Returns LTTNG_OK on success or an LTTng error code on failure.
836 */
837 static enum lttng_error_code send_consumer_relayd_socket(
838 unsigned int session_id,
839 struct lttng_uri *relayd_uri,
840 struct consumer_output *consumer,
841 struct consumer_socket *consumer_sock,
842 const char *session_name, const char *hostname,
843 const char *base_path, int session_live_timer,
844 const uint64_t *current_chunk_id,
845 time_t session_creation_time,
846 bool session_name_contains_creation_time)
847 {
848 int ret;
849 struct lttcomm_relayd_sock *rsock = NULL;
850 enum lttng_error_code status;
851
852 /* Connect to relayd and make version check if uri is the control. */
853 status = create_connect_relayd(relayd_uri, &rsock, consumer);
854 if (status != LTTNG_OK) {
855 goto relayd_comm_error;
856 }
857 LTTNG_ASSERT(rsock);
858
859 /* Set the network sequence index if not set. */
860 if (consumer->net_seq_index == (uint64_t) -1ULL) {
861 pthread_mutex_lock(&relayd_net_seq_idx_lock);
862 /*
863 * Increment net_seq_idx because we are about to transfer the
864 * new relayd socket to the consumer.
865 * Assign unique key so the consumer can match streams.
866 */
867 consumer->net_seq_index = ++relayd_net_seq_idx;
868 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
869 }
870
871 /* Send relayd socket to consumer. */
872 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
873 relayd_uri->stype, session_id,
874 session_name, hostname, base_path,
875 session_live_timer, current_chunk_id,
876 session_creation_time, session_name_contains_creation_time);
877 if (ret < 0) {
878 status = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
879 goto close_sock;
880 }
881
882 /* Flag that the corresponding socket was sent. */
883 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
884 consumer_sock->control_sock_sent = 1;
885 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
886 consumer_sock->data_sock_sent = 1;
887 }
888
889 /*
890 * Close socket which was dup on the consumer side. The session daemon does
891 * NOT keep track of the relayd socket(s) once transfer to the consumer.
892 */
893
894 close_sock:
895 if (status != LTTNG_OK) {
896 /*
897 * The consumer output for this session should not be used anymore
898 * since the relayd connection failed thus making any tracing or/and
899 * streaming not usable.
900 */
901 consumer->enabled = 0;
902 }
903 (void) relayd_close(rsock);
904 free(rsock);
905
906 relayd_comm_error:
907 return status;
908 }
909
910 /*
911 * Send both relayd sockets to a specific consumer and domain. This is a
912 * helper function to facilitate sending the information to the consumer for a
913 * session.
914 *
915 * The consumer socket lock must be held by the caller.
916 *
917 * Returns LTTNG_OK, or an LTTng error code on failure.
918 */
919 static enum lttng_error_code send_consumer_relayd_sockets(
920 enum lttng_domain_type domain,
921 unsigned int session_id, struct consumer_output *consumer,
922 struct consumer_socket *sock, const char *session_name,
923 const char *hostname, const char *base_path, int session_live_timer,
924 const uint64_t *current_chunk_id, time_t session_creation_time,
925 bool session_name_contains_creation_time)
926 {
927 enum lttng_error_code status = LTTNG_OK;
928
929 LTTNG_ASSERT(consumer);
930 LTTNG_ASSERT(sock);
931
932 /* Sending control relayd socket. */
933 if (!sock->control_sock_sent) {
934 status = send_consumer_relayd_socket(session_id,
935 &consumer->dst.net.control, consumer, sock,
936 session_name, hostname, base_path, session_live_timer,
937 current_chunk_id, session_creation_time,
938 session_name_contains_creation_time);
939 if (status != LTTNG_OK) {
940 goto error;
941 }
942 }
943
944 /* Sending data relayd socket. */
945 if (!sock->data_sock_sent) {
946 status = send_consumer_relayd_socket(session_id,
947 &consumer->dst.net.data, consumer, sock,
948 session_name, hostname, base_path, session_live_timer,
949 current_chunk_id, session_creation_time,
950 session_name_contains_creation_time);
951 if (status != LTTNG_OK) {
952 goto error;
953 }
954 }
955
956 error:
957 return status;
958 }
959
960 /*
961 * Setup relayd connections for a tracing session. First creates the socket to
962 * the relayd and send them to the right domain consumer. Consumer type MUST be
963 * network.
964 */
965 int cmd_setup_relayd(struct ltt_session *session)
966 {
967 int ret = LTTNG_OK;
968 struct ltt_ust_session *usess;
969 struct ltt_kernel_session *ksess;
970 struct consumer_socket *socket;
971 struct lttng_ht_iter iter;
972 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
973
974 LTTNG_ASSERT(session);
975
976 usess = session->ust_session;
977 ksess = session->kernel_session;
978
979 DBG("Setting relayd for session %s", session->name);
980
981 rcu_read_lock();
982 if (session->current_trace_chunk) {
983 enum lttng_trace_chunk_status status = lttng_trace_chunk_get_id(
984 session->current_trace_chunk, &current_chunk_id.value);
985
986 if (status == LTTNG_TRACE_CHUNK_STATUS_OK) {
987 current_chunk_id.is_set = true;
988 } else {
989 ERR("Failed to get current trace chunk id");
990 ret = LTTNG_ERR_UNK;
991 goto error;
992 }
993 }
994
995 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
996 && usess->consumer->enabled) {
997 /* For each consumer socket, send relayd sockets */
998 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
999 socket, node.node) {
1000 pthread_mutex_lock(socket->lock);
1001 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1002 usess->consumer, socket,
1003 session->name, session->hostname,
1004 session->base_path,
1005 session->live_timer,
1006 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1007 session->creation_time,
1008 session->name_contains_creation_time);
1009 pthread_mutex_unlock(socket->lock);
1010 if (ret != LTTNG_OK) {
1011 goto error;
1012 }
1013 /* Session is now ready for network streaming. */
1014 session->net_handle = 1;
1015 }
1016 session->consumer->relay_major_version =
1017 usess->consumer->relay_major_version;
1018 session->consumer->relay_minor_version =
1019 usess->consumer->relay_minor_version;
1020 session->consumer->relay_allows_clear =
1021 usess->consumer->relay_allows_clear;
1022 }
1023
1024 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1025 && ksess->consumer->enabled) {
1026 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1027 socket, node.node) {
1028 pthread_mutex_lock(socket->lock);
1029 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1030 ksess->consumer, socket,
1031 session->name, session->hostname,
1032 session->base_path,
1033 session->live_timer,
1034 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1035 session->creation_time,
1036 session->name_contains_creation_time);
1037 pthread_mutex_unlock(socket->lock);
1038 if (ret != LTTNG_OK) {
1039 goto error;
1040 }
1041 /* Session is now ready for network streaming. */
1042 session->net_handle = 1;
1043 }
1044 session->consumer->relay_major_version =
1045 ksess->consumer->relay_major_version;
1046 session->consumer->relay_minor_version =
1047 ksess->consumer->relay_minor_version;
1048 session->consumer->relay_allows_clear =
1049 ksess->consumer->relay_allows_clear;
1050 }
1051
1052 error:
1053 rcu_read_unlock();
1054 return ret;
1055 }
1056
1057 /*
1058 * Start a kernel session by opening all necessary streams.
1059 */
1060 int start_kernel_session(struct ltt_kernel_session *ksess)
1061 {
1062 int ret;
1063 struct ltt_kernel_channel *kchan;
1064
1065 /* Open kernel metadata */
1066 if (ksess->metadata == NULL && ksess->output_traces) {
1067 ret = kernel_open_metadata(ksess);
1068 if (ret < 0) {
1069 ret = LTTNG_ERR_KERN_META_FAIL;
1070 goto error;
1071 }
1072 }
1073
1074 /* Open kernel metadata stream */
1075 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1076 ret = kernel_open_metadata_stream(ksess);
1077 if (ret < 0) {
1078 ERR("Kernel create metadata stream failed");
1079 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1080 goto error;
1081 }
1082 }
1083
1084 /* For each channel */
1085 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1086 if (kchan->stream_count == 0) {
1087 ret = kernel_open_channel_stream(kchan);
1088 if (ret < 0) {
1089 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1090 goto error;
1091 }
1092 /* Update the stream global counter */
1093 ksess->stream_count_global += ret;
1094 }
1095 }
1096
1097 /* Setup kernel consumer socket and send fds to it */
1098 ret = init_kernel_tracing(ksess);
1099 if (ret != 0) {
1100 ret = LTTNG_ERR_KERN_START_FAIL;
1101 goto error;
1102 }
1103
1104 /* This start the kernel tracing */
1105 ret = kernel_start_session(ksess);
1106 if (ret < 0) {
1107 ret = LTTNG_ERR_KERN_START_FAIL;
1108 goto error;
1109 }
1110
1111 /* Quiescent wait after starting trace */
1112 kernel_wait_quiescent();
1113
1114 ksess->active = 1;
1115
1116 ret = LTTNG_OK;
1117
1118 error:
1119 return ret;
1120 }
1121
1122 int stop_kernel_session(struct ltt_kernel_session *ksess)
1123 {
1124 struct ltt_kernel_channel *kchan;
1125 bool error_occurred = false;
1126 int ret;
1127
1128 if (!ksess || !ksess->active) {
1129 return LTTNG_OK;
1130 }
1131 DBG("Stopping kernel tracing");
1132
1133 ret = kernel_stop_session(ksess);
1134 if (ret < 0) {
1135 ret = LTTNG_ERR_KERN_STOP_FAIL;
1136 goto error;
1137 }
1138
1139 kernel_wait_quiescent();
1140
1141 /* Flush metadata after stopping (if exists) */
1142 if (ksess->metadata_stream_fd >= 0) {
1143 ret = kernel_metadata_flush_buffer(ksess->metadata_stream_fd);
1144 if (ret < 0) {
1145 ERR("Kernel metadata flush failed");
1146 error_occurred = true;
1147 }
1148 }
1149
1150 /* Flush all buffers after stopping */
1151 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1152 ret = kernel_flush_buffer(kchan);
1153 if (ret < 0) {
1154 ERR("Kernel flush buffer error");
1155 error_occurred = true;
1156 }
1157 }
1158
1159 ksess->active = 0;
1160 if (error_occurred) {
1161 ret = LTTNG_ERR_UNK;
1162 } else {
1163 ret = LTTNG_OK;
1164 }
1165 error:
1166 return ret;
1167 }
1168
1169 /*
1170 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1171 */
1172 int cmd_disable_channel(struct ltt_session *session,
1173 enum lttng_domain_type domain, char *channel_name)
1174 {
1175 int ret;
1176 struct ltt_ust_session *usess;
1177
1178 usess = session->ust_session;
1179
1180 rcu_read_lock();
1181
1182 switch (domain) {
1183 case LTTNG_DOMAIN_KERNEL:
1184 {
1185 ret = channel_kernel_disable(session->kernel_session,
1186 channel_name);
1187 if (ret != LTTNG_OK) {
1188 goto error;
1189 }
1190
1191 kernel_wait_quiescent();
1192 break;
1193 }
1194 case LTTNG_DOMAIN_UST:
1195 {
1196 struct ltt_ust_channel *uchan;
1197 struct lttng_ht *chan_ht;
1198
1199 chan_ht = usess->domain_global.channels;
1200
1201 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1202 if (uchan == NULL) {
1203 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1204 goto error;
1205 }
1206
1207 ret = channel_ust_disable(usess, uchan);
1208 if (ret != LTTNG_OK) {
1209 goto error;
1210 }
1211 break;
1212 }
1213 default:
1214 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1215 goto error;
1216 }
1217
1218 ret = LTTNG_OK;
1219
1220 error:
1221 rcu_read_unlock();
1222 return ret;
1223 }
1224
1225 /*
1226 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1227 *
1228 * The wpipe arguments is used as a notifier for the kernel thread.
1229 */
1230 int cmd_enable_channel(struct command_ctx *cmd_ctx, int sock, int wpipe)
1231 {
1232 int ret;
1233 size_t channel_len;
1234 ssize_t sock_recv_len;
1235 struct lttng_channel *channel = NULL;
1236 struct lttng_buffer_view view;
1237 struct lttng_dynamic_buffer channel_buffer;
1238 const struct lttng_domain command_domain = cmd_ctx->lsm.domain;
1239
1240 lttng_dynamic_buffer_init(&channel_buffer);
1241 channel_len = (size_t) cmd_ctx->lsm.u.channel.length;
1242 ret = lttng_dynamic_buffer_set_size(&channel_buffer, channel_len);
1243 if (ret) {
1244 ret = LTTNG_ERR_NOMEM;
1245 goto end;
1246 }
1247
1248 sock_recv_len = lttcomm_recv_unix_sock(sock, channel_buffer.data,
1249 channel_len);
1250 if (sock_recv_len < 0 || sock_recv_len != channel_len) {
1251 ERR("Failed to receive \"enable channel\" command payload");
1252 ret = LTTNG_ERR_INVALID;
1253 goto end;
1254 }
1255
1256 view = lttng_buffer_view_from_dynamic_buffer(&channel_buffer, 0, channel_len);
1257 if (!lttng_buffer_view_is_valid(&view)) {
1258 ret = LTTNG_ERR_INVALID;
1259 goto end;
1260 }
1261
1262 if (lttng_channel_create_from_buffer(&view, &channel) != channel_len) {
1263 ERR("Invalid channel payload received in \"enable channel\" command");
1264 ret = LTTNG_ERR_INVALID;
1265 goto end;
1266 }
1267
1268 ret = cmd_enable_channel_internal(
1269 cmd_ctx->session, &command_domain, channel, wpipe);
1270
1271 end:
1272 lttng_dynamic_buffer_reset(&channel_buffer);
1273 lttng_channel_destroy(channel);
1274 return ret;
1275 }
1276
1277 static int cmd_enable_channel_internal(struct ltt_session *session,
1278 const struct lttng_domain *domain,
1279 const struct lttng_channel *_attr,
1280 int wpipe)
1281 {
1282 int ret;
1283 struct ltt_ust_session *usess = session->ust_session;
1284 struct lttng_ht *chan_ht;
1285 size_t len;
1286 struct lttng_channel *attr = NULL;
1287
1288 LTTNG_ASSERT(session);
1289 LTTNG_ASSERT(_attr);
1290 LTTNG_ASSERT(domain);
1291
1292 attr = lttng_channel_copy(_attr);
1293 if (!attr) {
1294 ret = -LTTNG_ERR_NOMEM;
1295 goto end;
1296 }
1297
1298 len = lttng_strnlen(attr->name, sizeof(attr->name));
1299
1300 /* Validate channel name */
1301 if (attr->name[0] == '.' ||
1302 memchr(attr->name, '/', len) != NULL) {
1303 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1304 goto end;
1305 }
1306
1307 DBG("Enabling channel %s for session %s", attr->name, session->name);
1308
1309 rcu_read_lock();
1310
1311 /*
1312 * If the session is a live session, remove the switch timer, the
1313 * live timer does the same thing but sends also synchronisation
1314 * beacons for inactive streams.
1315 */
1316 if (session->live_timer > 0) {
1317 attr->attr.live_timer_interval = session->live_timer;
1318 attr->attr.switch_timer_interval = 0;
1319 }
1320
1321 /* Check for feature support */
1322 switch (domain->type) {
1323 case LTTNG_DOMAIN_KERNEL:
1324 {
1325 if (kernel_supports_ring_buffer_snapshot_sample_positions() != 1) {
1326 /* Sampling position of buffer is not supported */
1327 WARN("Kernel tracer does not support buffer monitoring. "
1328 "Setting the monitor interval timer to 0 "
1329 "(disabled) for channel '%s' of session '%s'",
1330 attr->name, session->name);
1331 lttng_channel_set_monitor_timer_interval(attr, 0);
1332 }
1333 break;
1334 }
1335 case LTTNG_DOMAIN_UST:
1336 break;
1337 case LTTNG_DOMAIN_JUL:
1338 case LTTNG_DOMAIN_LOG4J:
1339 case LTTNG_DOMAIN_PYTHON:
1340 if (!agent_tracing_is_enabled()) {
1341 DBG("Attempted to enable a channel in an agent domain but the agent thread is not running");
1342 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
1343 goto error;
1344 }
1345 break;
1346 default:
1347 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1348 goto error;
1349 }
1350
1351 switch (domain->type) {
1352 case LTTNG_DOMAIN_KERNEL:
1353 {
1354 struct ltt_kernel_channel *kchan;
1355
1356 kchan = trace_kernel_get_channel_by_name(
1357 attr->name, session->kernel_session);
1358 if (kchan == NULL) {
1359 /*
1360 * Don't try to create a channel if the session has been started at
1361 * some point in time before. The tracer does not allow it.
1362 */
1363 if (session->has_been_started) {
1364 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1365 goto error;
1366 }
1367
1368 if (session->snapshot.nb_output > 0 ||
1369 session->snapshot_mode) {
1370 /* Enforce mmap output for snapshot sessions. */
1371 attr->attr.output = LTTNG_EVENT_MMAP;
1372 }
1373 ret = channel_kernel_create(
1374 session->kernel_session, attr, wpipe);
1375 if (attr->name[0] != '\0') {
1376 session->kernel_session->has_non_default_channel = 1;
1377 }
1378 } else {
1379 ret = channel_kernel_enable(session->kernel_session, kchan);
1380 }
1381
1382 if (ret != LTTNG_OK) {
1383 goto error;
1384 }
1385
1386 kernel_wait_quiescent();
1387 break;
1388 }
1389 case LTTNG_DOMAIN_UST:
1390 case LTTNG_DOMAIN_JUL:
1391 case LTTNG_DOMAIN_LOG4J:
1392 case LTTNG_DOMAIN_PYTHON:
1393 {
1394 struct ltt_ust_channel *uchan;
1395
1396 /*
1397 * FIXME
1398 *
1399 * Current agent implementation limitations force us to allow
1400 * only one channel at once in "agent" subdomains. Each
1401 * subdomain has a default channel name which must be strictly
1402 * adhered to.
1403 */
1404 if (domain->type == LTTNG_DOMAIN_JUL) {
1405 if (strncmp(attr->name, DEFAULT_JUL_CHANNEL_NAME,
1406 LTTNG_SYMBOL_NAME_LEN)) {
1407 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1408 goto error;
1409 }
1410 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1411 if (strncmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME,
1412 LTTNG_SYMBOL_NAME_LEN)) {
1413 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1414 goto error;
1415 }
1416 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1417 if (strncmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME,
1418 LTTNG_SYMBOL_NAME_LEN)) {
1419 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1420 goto error;
1421 }
1422 }
1423
1424 chan_ht = usess->domain_global.channels;
1425
1426 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1427 if (uchan == NULL) {
1428 /*
1429 * Don't try to create a channel if the session has been started at
1430 * some point in time before. The tracer does not allow it.
1431 */
1432 if (session->has_been_started) {
1433 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1434 goto error;
1435 }
1436
1437 ret = channel_ust_create(usess, attr, domain->buf_type);
1438 if (attr->name[0] != '\0') {
1439 usess->has_non_default_channel = 1;
1440 }
1441 } else {
1442 ret = channel_ust_enable(usess, uchan);
1443 }
1444 break;
1445 }
1446 default:
1447 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1448 goto error;
1449 }
1450
1451 if (ret == LTTNG_OK && attr->attr.output != LTTNG_EVENT_MMAP) {
1452 session->has_non_mmap_channel = true;
1453 }
1454 error:
1455 rcu_read_unlock();
1456 end:
1457 lttng_channel_destroy(attr);
1458 return ret;
1459 }
1460
1461 enum lttng_error_code cmd_process_attr_tracker_get_tracking_policy(
1462 struct ltt_session *session,
1463 enum lttng_domain_type domain,
1464 enum lttng_process_attr process_attr,
1465 enum lttng_tracking_policy *policy)
1466 {
1467 enum lttng_error_code ret_code = LTTNG_OK;
1468 const struct process_attr_tracker *tracker;
1469
1470 switch (domain) {
1471 case LTTNG_DOMAIN_KERNEL:
1472 if (!session->kernel_session) {
1473 ret_code = LTTNG_ERR_INVALID;
1474 goto end;
1475 }
1476 tracker = kernel_get_process_attr_tracker(
1477 session->kernel_session, process_attr);
1478 break;
1479 case LTTNG_DOMAIN_UST:
1480 if (!session->ust_session) {
1481 ret_code = LTTNG_ERR_INVALID;
1482 goto end;
1483 }
1484 tracker = trace_ust_get_process_attr_tracker(
1485 session->ust_session, process_attr);
1486 break;
1487 default:
1488 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1489 goto end;
1490 }
1491 if (tracker) {
1492 *policy = process_attr_tracker_get_tracking_policy(tracker);
1493 } else {
1494 ret_code = LTTNG_ERR_INVALID;
1495 }
1496 end:
1497 return ret_code;
1498 }
1499
1500 enum lttng_error_code cmd_process_attr_tracker_set_tracking_policy(
1501 struct ltt_session *session,
1502 enum lttng_domain_type domain,
1503 enum lttng_process_attr process_attr,
1504 enum lttng_tracking_policy policy)
1505 {
1506 enum lttng_error_code ret_code = LTTNG_OK;
1507
1508 switch (policy) {
1509 case LTTNG_TRACKING_POLICY_INCLUDE_SET:
1510 case LTTNG_TRACKING_POLICY_EXCLUDE_ALL:
1511 case LTTNG_TRACKING_POLICY_INCLUDE_ALL:
1512 break;
1513 default:
1514 ret_code = LTTNG_ERR_INVALID;
1515 goto end;
1516 }
1517
1518 switch (domain) {
1519 case LTTNG_DOMAIN_KERNEL:
1520 if (!session->kernel_session) {
1521 ret_code = LTTNG_ERR_INVALID;
1522 goto end;
1523 }
1524 ret_code = kernel_process_attr_tracker_set_tracking_policy(
1525 session->kernel_session, process_attr, policy);
1526 break;
1527 case LTTNG_DOMAIN_UST:
1528 if (!session->ust_session) {
1529 ret_code = LTTNG_ERR_INVALID;
1530 goto end;
1531 }
1532 ret_code = trace_ust_process_attr_tracker_set_tracking_policy(
1533 session->ust_session, process_attr, policy);
1534 break;
1535 default:
1536 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1537 break;
1538 }
1539 end:
1540 return ret_code;
1541 }
1542
1543 enum lttng_error_code cmd_process_attr_tracker_inclusion_set_add_value(
1544 struct ltt_session *session,
1545 enum lttng_domain_type domain,
1546 enum lttng_process_attr process_attr,
1547 const struct process_attr_value *value)
1548 {
1549 enum lttng_error_code ret_code = LTTNG_OK;
1550
1551 switch (domain) {
1552 case LTTNG_DOMAIN_KERNEL:
1553 if (!session->kernel_session) {
1554 ret_code = LTTNG_ERR_INVALID;
1555 goto end;
1556 }
1557 ret_code = kernel_process_attr_tracker_inclusion_set_add_value(
1558 session->kernel_session, process_attr, value);
1559 break;
1560 case LTTNG_DOMAIN_UST:
1561 if (!session->ust_session) {
1562 ret_code = LTTNG_ERR_INVALID;
1563 goto end;
1564 }
1565 ret_code = trace_ust_process_attr_tracker_inclusion_set_add_value(
1566 session->ust_session, process_attr, value);
1567 break;
1568 default:
1569 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1570 break;
1571 }
1572 end:
1573 return ret_code;
1574 }
1575
1576 enum lttng_error_code cmd_process_attr_tracker_inclusion_set_remove_value(
1577 struct ltt_session *session,
1578 enum lttng_domain_type domain,
1579 enum lttng_process_attr process_attr,
1580 const struct process_attr_value *value)
1581 {
1582 enum lttng_error_code ret_code = LTTNG_OK;
1583
1584 switch (domain) {
1585 case LTTNG_DOMAIN_KERNEL:
1586 if (!session->kernel_session) {
1587 ret_code = LTTNG_ERR_INVALID;
1588 goto end;
1589 }
1590 ret_code = kernel_process_attr_tracker_inclusion_set_remove_value(
1591 session->kernel_session, process_attr, value);
1592 break;
1593 case LTTNG_DOMAIN_UST:
1594 if (!session->ust_session) {
1595 ret_code = LTTNG_ERR_INVALID;
1596 goto end;
1597 }
1598 ret_code = trace_ust_process_attr_tracker_inclusion_set_remove_value(
1599 session->ust_session, process_attr, value);
1600 break;
1601 default:
1602 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1603 break;
1604 }
1605 end:
1606 return ret_code;
1607 }
1608
1609 enum lttng_error_code cmd_process_attr_tracker_get_inclusion_set(
1610 struct ltt_session *session,
1611 enum lttng_domain_type domain,
1612 enum lttng_process_attr process_attr,
1613 struct lttng_process_attr_values **values)
1614 {
1615 enum lttng_error_code ret_code = LTTNG_OK;
1616 const struct process_attr_tracker *tracker;
1617 enum process_attr_tracker_status status;
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 tracker = kernel_get_process_attr_tracker(
1626 session->kernel_session, process_attr);
1627 break;
1628 case LTTNG_DOMAIN_UST:
1629 if (!session->ust_session) {
1630 ret_code = LTTNG_ERR_INVALID;
1631 goto end;
1632 }
1633 tracker = trace_ust_get_process_attr_tracker(
1634 session->ust_session, process_attr);
1635 break;
1636 default:
1637 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1638 goto end;
1639 }
1640
1641 if (!tracker) {
1642 ret_code = LTTNG_ERR_INVALID;
1643 goto end;
1644 }
1645
1646 status = process_attr_tracker_get_inclusion_set(tracker, values);
1647 switch (status) {
1648 case PROCESS_ATTR_TRACKER_STATUS_OK:
1649 ret_code = LTTNG_OK;
1650 break;
1651 case PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY:
1652 ret_code = LTTNG_ERR_PROCESS_ATTR_TRACKER_INVALID_TRACKING_POLICY;
1653 break;
1654 case PROCESS_ATTR_TRACKER_STATUS_ERROR:
1655 ret_code = LTTNG_ERR_NOMEM;
1656 break;
1657 default:
1658 ret_code = LTTNG_ERR_UNK;
1659 break;
1660 }
1661
1662 end:
1663 return ret_code;
1664 }
1665
1666 /*
1667 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1668 */
1669 int cmd_disable_event(struct command_ctx *cmd_ctx,
1670 struct lttng_event *event,
1671 char *filter_expression,
1672 struct lttng_bytecode *bytecode,
1673 struct lttng_event_exclusion *exclusion)
1674 {
1675 int ret;
1676 const char *event_name;
1677 const struct ltt_session *session = cmd_ctx->session;
1678 const char *channel_name = cmd_ctx->lsm.u.disable.channel_name;
1679 const enum lttng_domain_type domain = cmd_ctx->lsm.domain.type;
1680
1681 DBG("Disable event command for event \'%s\'", event->name);
1682
1683 /*
1684 * Filter and exclusions are simply not handled by the
1685 * disable event command at this time.
1686 *
1687 * FIXME
1688 */
1689 (void) filter_expression;
1690 (void) exclusion;
1691
1692 /* Ignore the presence of filter or exclusion for the event */
1693 event->filter = 0;
1694 event->exclusion = 0;
1695
1696 event_name = event->name;
1697
1698 /* Error out on unhandled search criteria */
1699 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1700 || event->pid || event->filter || event->exclusion) {
1701 ret = LTTNG_ERR_UNK;
1702 goto error;
1703 }
1704
1705 rcu_read_lock();
1706
1707 switch (domain) {
1708 case LTTNG_DOMAIN_KERNEL:
1709 {
1710 struct ltt_kernel_channel *kchan;
1711 struct ltt_kernel_session *ksess;
1712
1713 ksess = session->kernel_session;
1714
1715 /*
1716 * If a non-default channel has been created in the
1717 * session, explicitely require that -c chan_name needs
1718 * to be provided.
1719 */
1720 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1721 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1722 goto error_unlock;
1723 }
1724
1725 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1726 if (kchan == NULL) {
1727 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1728 goto error_unlock;
1729 }
1730
1731 switch (event->type) {
1732 case LTTNG_EVENT_ALL:
1733 case LTTNG_EVENT_TRACEPOINT:
1734 case LTTNG_EVENT_SYSCALL:
1735 case LTTNG_EVENT_PROBE:
1736 case LTTNG_EVENT_FUNCTION:
1737 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1738 if (event_name[0] == '\0') {
1739 ret = event_kernel_disable_event(kchan,
1740 NULL, event->type);
1741 } else {
1742 ret = event_kernel_disable_event(kchan,
1743 event_name, event->type);
1744 }
1745 if (ret != LTTNG_OK) {
1746 goto error_unlock;
1747 }
1748 break;
1749 default:
1750 ret = LTTNG_ERR_UNK;
1751 goto error_unlock;
1752 }
1753
1754 kernel_wait_quiescent();
1755 break;
1756 }
1757 case LTTNG_DOMAIN_UST:
1758 {
1759 struct ltt_ust_channel *uchan;
1760 struct ltt_ust_session *usess;
1761
1762 usess = session->ust_session;
1763
1764 if (validate_ust_event_name(event_name)) {
1765 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1766 goto error_unlock;
1767 }
1768
1769 /*
1770 * If a non-default channel has been created in the
1771 * session, explicitly require that -c chan_name needs
1772 * to be provided.
1773 */
1774 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1775 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1776 goto error_unlock;
1777 }
1778
1779 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1780 channel_name);
1781 if (uchan == NULL) {
1782 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1783 goto error_unlock;
1784 }
1785
1786 switch (event->type) {
1787 case LTTNG_EVENT_ALL:
1788 /*
1789 * An empty event name means that everything
1790 * should be disabled.
1791 */
1792 if (event->name[0] == '\0') {
1793 ret = event_ust_disable_all_tracepoints(usess, uchan);
1794 } else {
1795 ret = event_ust_disable_tracepoint(usess, uchan,
1796 event_name);
1797 }
1798 if (ret != LTTNG_OK) {
1799 goto error_unlock;
1800 }
1801 break;
1802 default:
1803 ret = LTTNG_ERR_UNK;
1804 goto error_unlock;
1805 }
1806
1807 DBG3("Disable UST event %s in channel %s completed", event_name,
1808 channel_name);
1809 break;
1810 }
1811 case LTTNG_DOMAIN_LOG4J:
1812 case LTTNG_DOMAIN_JUL:
1813 case LTTNG_DOMAIN_PYTHON:
1814 {
1815 struct agent *agt;
1816 struct ltt_ust_session *usess = session->ust_session;
1817
1818 LTTNG_ASSERT(usess);
1819
1820 switch (event->type) {
1821 case LTTNG_EVENT_ALL:
1822 break;
1823 default:
1824 ret = LTTNG_ERR_UNK;
1825 goto error_unlock;
1826 }
1827
1828 agt = trace_ust_find_agent(usess, domain);
1829 if (!agt) {
1830 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1831 goto error_unlock;
1832 }
1833 /*
1834 * An empty event name means that everything
1835 * should be disabled.
1836 */
1837 if (event->name[0] == '\0') {
1838 ret = event_agent_disable_all(usess, agt);
1839 } else {
1840 ret = event_agent_disable(usess, agt, event_name);
1841 }
1842 if (ret != LTTNG_OK) {
1843 goto error_unlock;
1844 }
1845
1846 break;
1847 }
1848 default:
1849 ret = LTTNG_ERR_UND;
1850 goto error_unlock;
1851 }
1852
1853 ret = LTTNG_OK;
1854
1855 error_unlock:
1856 rcu_read_unlock();
1857 error:
1858 free(exclusion);
1859 free(bytecode);
1860 free(filter_expression);
1861 return ret;
1862 }
1863
1864 /*
1865 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1866 */
1867 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1868 char *channel_name, const struct lttng_event_context *ctx, int kwpipe)
1869 {
1870 int ret, chan_kern_created = 0, chan_ust_created = 0;
1871 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1872
1873 /*
1874 * Don't try to add a context if the session has been started at
1875 * some point in time before. The tracer does not allow it and would
1876 * result in a corrupted trace.
1877 */
1878 if (session->has_been_started) {
1879 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1880 goto end;
1881 }
1882
1883 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1884 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1885 app_ctx_name = ctx->u.app_ctx.ctx_name;
1886 }
1887
1888 switch (domain) {
1889 case LTTNG_DOMAIN_KERNEL:
1890 LTTNG_ASSERT(session->kernel_session);
1891
1892 if (session->kernel_session->channel_count == 0) {
1893 /* Create default channel */
1894 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1895 if (ret != LTTNG_OK) {
1896 goto error;
1897 }
1898 chan_kern_created = 1;
1899 }
1900 /* Add kernel context to kernel tracer */
1901 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1902 if (ret != LTTNG_OK) {
1903 goto error;
1904 }
1905 break;
1906 case LTTNG_DOMAIN_JUL:
1907 case LTTNG_DOMAIN_LOG4J:
1908 {
1909 /*
1910 * Validate channel name.
1911 * If no channel name is given and the domain is JUL or LOG4J,
1912 * set it to the appropriate domain-specific channel name. If
1913 * a name is provided but does not match the expexted channel
1914 * name, return an error.
1915 */
1916 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1917 strcmp(channel_name,
1918 DEFAULT_JUL_CHANNEL_NAME)) {
1919 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1920 goto error;
1921 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1922 strcmp(channel_name,
1923 DEFAULT_LOG4J_CHANNEL_NAME)) {
1924 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1925 goto error;
1926 }
1927 /* break is _not_ missing here. */
1928 }
1929 case LTTNG_DOMAIN_UST:
1930 {
1931 struct ltt_ust_session *usess = session->ust_session;
1932 unsigned int chan_count;
1933
1934 LTTNG_ASSERT(usess);
1935
1936 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1937 if (chan_count == 0) {
1938 struct lttng_channel *attr;
1939 /* Create default channel */
1940 attr = channel_new_default_attr(domain, usess->buffer_type);
1941 if (attr == NULL) {
1942 ret = LTTNG_ERR_FATAL;
1943 goto error;
1944 }
1945
1946 ret = channel_ust_create(usess, attr, usess->buffer_type);
1947 if (ret != LTTNG_OK) {
1948 free(attr);
1949 goto error;
1950 }
1951 channel_attr_destroy(attr);
1952 chan_ust_created = 1;
1953 }
1954
1955 ret = context_ust_add(usess, domain, ctx, channel_name);
1956 free(app_ctx_provider_name);
1957 free(app_ctx_name);
1958 app_ctx_name = NULL;
1959 app_ctx_provider_name = NULL;
1960 if (ret != LTTNG_OK) {
1961 goto error;
1962 }
1963 break;
1964 }
1965 default:
1966 ret = LTTNG_ERR_UND;
1967 goto error;
1968 }
1969
1970 ret = LTTNG_OK;
1971 goto end;
1972
1973 error:
1974 if (chan_kern_created) {
1975 struct ltt_kernel_channel *kchan =
1976 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1977 session->kernel_session);
1978 /* Created previously, this should NOT fail. */
1979 LTTNG_ASSERT(kchan);
1980 kernel_destroy_channel(kchan);
1981 }
1982
1983 if (chan_ust_created) {
1984 struct ltt_ust_channel *uchan =
1985 trace_ust_find_channel_by_name(
1986 session->ust_session->domain_global.channels,
1987 DEFAULT_CHANNEL_NAME);
1988 /* Created previously, this should NOT fail. */
1989 LTTNG_ASSERT(uchan);
1990 /* Remove from the channel list of the session. */
1991 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1992 uchan);
1993 trace_ust_destroy_channel(uchan);
1994 }
1995 end:
1996 free(app_ctx_provider_name);
1997 free(app_ctx_name);
1998 return ret;
1999 }
2000
2001 static inline bool name_starts_with(const char *name, const char *prefix)
2002 {
2003 const size_t max_cmp_len = std::min(strlen(prefix), (size_t) LTTNG_SYMBOL_NAME_LEN);
2004
2005 return !strncmp(name, prefix, max_cmp_len);
2006 }
2007
2008 /* Perform userspace-specific event name validation */
2009 static int validate_ust_event_name(const char *name)
2010 {
2011 int ret = 0;
2012
2013 if (!name) {
2014 ret = -1;
2015 goto end;
2016 }
2017
2018 /*
2019 * Check name against all internal UST event component namespaces used
2020 * by the agents.
2021 */
2022 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
2023 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
2024 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
2025 ret = -1;
2026 }
2027
2028 end:
2029 return ret;
2030 }
2031
2032 /*
2033 * Internal version of cmd_enable_event() with a supplemental
2034 * "internal_event" flag which is used to enable internal events which should
2035 * be hidden from clients. Such events are used in the agent implementation to
2036 * enable the events through which all "agent" events are funeled.
2037 */
2038 static int _cmd_enable_event(struct ltt_session *session,
2039 const struct lttng_domain *domain,
2040 char *channel_name, struct lttng_event *event,
2041 char *filter_expression,
2042 struct lttng_bytecode *filter,
2043 struct lttng_event_exclusion *exclusion,
2044 int wpipe, bool internal_event)
2045 {
2046 int ret = 0, channel_created = 0;
2047 struct lttng_channel *attr = NULL;
2048
2049 LTTNG_ASSERT(session);
2050 LTTNG_ASSERT(event);
2051 LTTNG_ASSERT(channel_name);
2052
2053 /* If we have a filter, we must have its filter expression */
2054 LTTNG_ASSERT(!(!!filter_expression ^ !!filter));
2055
2056 /* Normalize event name as a globbing pattern */
2057 strutils_normalize_star_glob_pattern(event->name);
2058
2059 /* Normalize exclusion names as globbing patterns */
2060 if (exclusion) {
2061 size_t i;
2062
2063 for (i = 0; i < exclusion->count; i++) {
2064 char *name = LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
2065
2066 strutils_normalize_star_glob_pattern(name);
2067 }
2068 }
2069
2070 DBG("Enable event command for event \'%s\'", event->name);
2071
2072 rcu_read_lock();
2073
2074 switch (domain->type) {
2075 case LTTNG_DOMAIN_KERNEL:
2076 {
2077 struct ltt_kernel_channel *kchan;
2078
2079 /*
2080 * If a non-default channel has been created in the
2081 * session, explicitely require that -c chan_name needs
2082 * to be provided.
2083 */
2084 if (session->kernel_session->has_non_default_channel
2085 && channel_name[0] == '\0') {
2086 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2087 goto error;
2088 }
2089
2090 kchan = trace_kernel_get_channel_by_name(channel_name,
2091 session->kernel_session);
2092 if (kchan == NULL) {
2093 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
2094 LTTNG_BUFFER_GLOBAL);
2095 if (attr == NULL) {
2096 ret = LTTNG_ERR_FATAL;
2097 goto error;
2098 }
2099 if (lttng_strncpy(attr->name, channel_name,
2100 sizeof(attr->name))) {
2101 ret = LTTNG_ERR_INVALID;
2102 goto error;
2103 }
2104
2105 ret = cmd_enable_channel_internal(
2106 session, domain, attr, wpipe);
2107 if (ret != LTTNG_OK) {
2108 goto error;
2109 }
2110 channel_created = 1;
2111 }
2112
2113 /* Get the newly created kernel channel pointer */
2114 kchan = trace_kernel_get_channel_by_name(channel_name,
2115 session->kernel_session);
2116 if (kchan == NULL) {
2117 /* This sould not happen... */
2118 ret = LTTNG_ERR_FATAL;
2119 goto error;
2120 }
2121
2122 switch (event->type) {
2123 case LTTNG_EVENT_ALL:
2124 {
2125 char *filter_expression_a = NULL;
2126 struct lttng_bytecode *filter_a = NULL;
2127
2128 /*
2129 * We need to duplicate filter_expression and filter,
2130 * because ownership is passed to first enable
2131 * event.
2132 */
2133 if (filter_expression) {
2134 filter_expression_a = strdup(filter_expression);
2135 if (!filter_expression_a) {
2136 ret = LTTNG_ERR_FATAL;
2137 goto error;
2138 }
2139 }
2140 if (filter) {
2141 filter_a = (lttng_bytecode *) zmalloc(sizeof(*filter_a) + filter->len);
2142 if (!filter_a) {
2143 free(filter_expression_a);
2144 ret = LTTNG_ERR_FATAL;
2145 goto error;
2146 }
2147 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
2148 }
2149 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
2150 ret = event_kernel_enable_event(kchan, event,
2151 filter_expression, filter);
2152 /* We have passed ownership */
2153 filter_expression = NULL;
2154 filter = NULL;
2155 if (ret != LTTNG_OK) {
2156 if (channel_created) {
2157 /* Let's not leak a useless channel. */
2158 kernel_destroy_channel(kchan);
2159 }
2160 free(filter_expression_a);
2161 free(filter_a);
2162 goto error;
2163 }
2164 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
2165 ret = event_kernel_enable_event(kchan, event,
2166 filter_expression_a, filter_a);
2167 /* We have passed ownership */
2168 filter_expression_a = NULL;
2169 filter_a = NULL;
2170 if (ret != LTTNG_OK) {
2171 goto error;
2172 }
2173 break;
2174 }
2175 case LTTNG_EVENT_PROBE:
2176 case LTTNG_EVENT_USERSPACE_PROBE:
2177 case LTTNG_EVENT_FUNCTION:
2178 case LTTNG_EVENT_FUNCTION_ENTRY:
2179 case LTTNG_EVENT_TRACEPOINT:
2180 ret = event_kernel_enable_event(kchan, event,
2181 filter_expression, filter);
2182 /* We have passed ownership */
2183 filter_expression = NULL;
2184 filter = NULL;
2185 if (ret != LTTNG_OK) {
2186 if (channel_created) {
2187 /* Let's not leak a useless channel. */
2188 kernel_destroy_channel(kchan);
2189 }
2190 goto error;
2191 }
2192 break;
2193 case LTTNG_EVENT_SYSCALL:
2194 ret = event_kernel_enable_event(kchan, event,
2195 filter_expression, filter);
2196 /* We have passed ownership */
2197 filter_expression = NULL;
2198 filter = NULL;
2199 if (ret != LTTNG_OK) {
2200 goto error;
2201 }
2202 break;
2203 default:
2204 ret = LTTNG_ERR_UNK;
2205 goto error;
2206 }
2207
2208 kernel_wait_quiescent();
2209 break;
2210 }
2211 case LTTNG_DOMAIN_UST:
2212 {
2213 struct ltt_ust_channel *uchan;
2214 struct ltt_ust_session *usess = session->ust_session;
2215
2216 LTTNG_ASSERT(usess);
2217
2218 /*
2219 * If a non-default channel has been created in the
2220 * session, explicitely require that -c chan_name needs
2221 * to be provided.
2222 */
2223 if (usess->has_non_default_channel && channel_name[0] == '\0') {
2224 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2225 goto error;
2226 }
2227
2228 /* Get channel from global UST domain */
2229 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2230 channel_name);
2231 if (uchan == NULL) {
2232 /* Create default channel */
2233 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
2234 usess->buffer_type);
2235 if (attr == NULL) {
2236 ret = LTTNG_ERR_FATAL;
2237 goto error;
2238 }
2239 if (lttng_strncpy(attr->name, channel_name,
2240 sizeof(attr->name))) {
2241 ret = LTTNG_ERR_INVALID;
2242 goto error;
2243 }
2244
2245 ret = cmd_enable_channel_internal(
2246 session, domain, attr, wpipe);
2247 if (ret != LTTNG_OK) {
2248 goto error;
2249 }
2250
2251 /* Get the newly created channel reference back */
2252 uchan = trace_ust_find_channel_by_name(
2253 usess->domain_global.channels, channel_name);
2254 LTTNG_ASSERT(uchan);
2255 }
2256
2257 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2258 /*
2259 * Don't allow users to add UST events to channels which
2260 * are assigned to a userspace subdomain (JUL, Log4J,
2261 * Python, etc.).
2262 */
2263 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2264 goto error;
2265 }
2266
2267 if (!internal_event) {
2268 /*
2269 * Ensure the event name is not reserved for internal
2270 * use.
2271 */
2272 ret = validate_ust_event_name(event->name);
2273 if (ret) {
2274 WARN("Userspace event name %s failed validation.",
2275 event->name);
2276 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2277 goto error;
2278 }
2279 }
2280
2281 /* At this point, the session and channel exist on the tracer */
2282 ret = event_ust_enable_tracepoint(usess, uchan, event,
2283 filter_expression, filter, exclusion,
2284 internal_event);
2285 /* We have passed ownership */
2286 filter_expression = NULL;
2287 filter = NULL;
2288 exclusion = NULL;
2289 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2290 goto already_enabled;
2291 } else if (ret != LTTNG_OK) {
2292 goto error;
2293 }
2294 break;
2295 }
2296 case LTTNG_DOMAIN_LOG4J:
2297 case LTTNG_DOMAIN_JUL:
2298 case LTTNG_DOMAIN_PYTHON:
2299 {
2300 const char *default_event_name, *default_chan_name;
2301 struct agent *agt;
2302 struct lttng_event uevent;
2303 struct lttng_domain tmp_dom;
2304 struct ltt_ust_session *usess = session->ust_session;
2305
2306 LTTNG_ASSERT(usess);
2307
2308 if (!agent_tracing_is_enabled()) {
2309 DBG("Attempted to enable an event in an agent domain but the agent thread is not running");
2310 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
2311 goto error;
2312 }
2313
2314 agt = trace_ust_find_agent(usess, domain->type);
2315 if (!agt) {
2316 agt = agent_create(domain->type);
2317 if (!agt) {
2318 ret = LTTNG_ERR_NOMEM;
2319 goto error;
2320 }
2321 agent_add(agt, usess->agents);
2322 }
2323
2324 /* Create the default tracepoint. */
2325 memset(&uevent, 0, sizeof(uevent));
2326 uevent.type = LTTNG_EVENT_TRACEPOINT;
2327 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2328 default_event_name = event_get_default_agent_ust_name(
2329 domain->type);
2330 if (!default_event_name) {
2331 ret = LTTNG_ERR_FATAL;
2332 goto error;
2333 }
2334 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2335 uevent.name[sizeof(uevent.name) - 1] = '\0';
2336
2337 /*
2338 * The domain type is changed because we are about to enable the
2339 * default channel and event for the JUL domain that are hardcoded.
2340 * This happens in the UST domain.
2341 */
2342 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2343 tmp_dom.type = LTTNG_DOMAIN_UST;
2344
2345 switch (domain->type) {
2346 case LTTNG_DOMAIN_LOG4J:
2347 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2348 break;
2349 case LTTNG_DOMAIN_JUL:
2350 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2351 break;
2352 case LTTNG_DOMAIN_PYTHON:
2353 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2354 break;
2355 default:
2356 /* The switch/case we are in makes this impossible */
2357 abort();
2358 }
2359
2360 {
2361 char *filter_expression_copy = NULL;
2362 struct lttng_bytecode *filter_copy = NULL;
2363
2364 if (filter) {
2365 const size_t filter_size = sizeof(
2366 struct lttng_bytecode)
2367 + filter->len;
2368
2369 filter_copy = (lttng_bytecode *) zmalloc(filter_size);
2370 if (!filter_copy) {
2371 ret = LTTNG_ERR_NOMEM;
2372 goto error;
2373 }
2374 memcpy(filter_copy, filter, filter_size);
2375
2376 filter_expression_copy =
2377 strdup(filter_expression);
2378 if (!filter_expression) {
2379 ret = LTTNG_ERR_NOMEM;
2380 }
2381
2382 if (!filter_expression_copy || !filter_copy) {
2383 free(filter_expression_copy);
2384 free(filter_copy);
2385 goto error;
2386 }
2387 }
2388
2389 ret = cmd_enable_event_internal(session, &tmp_dom,
2390 (char *) default_chan_name,
2391 &uevent, filter_expression_copy,
2392 filter_copy, NULL, wpipe);
2393 }
2394
2395 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2396 goto already_enabled;
2397 } else if (ret != LTTNG_OK) {
2398 goto error;
2399 }
2400
2401 /* The wild card * means that everything should be enabled. */
2402 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2403 ret = event_agent_enable_all(usess, agt, event, filter,
2404 filter_expression);
2405 } else {
2406 ret = event_agent_enable(usess, agt, event, filter,
2407 filter_expression);
2408 }
2409 filter = NULL;
2410 filter_expression = NULL;
2411 if (ret != LTTNG_OK) {
2412 goto error;
2413 }
2414
2415 break;
2416 }
2417 default:
2418 ret = LTTNG_ERR_UND;
2419 goto error;
2420 }
2421
2422 ret = LTTNG_OK;
2423
2424 already_enabled:
2425 error:
2426 free(filter_expression);
2427 free(filter);
2428 free(exclusion);
2429 channel_attr_destroy(attr);
2430 rcu_read_unlock();
2431 return ret;
2432 }
2433
2434 /*
2435 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2436 * We own filter, exclusion, and filter_expression.
2437 */
2438 int cmd_enable_event(struct command_ctx *cmd_ctx,
2439 struct lttng_event *event,
2440 char *filter_expression,
2441 struct lttng_event_exclusion *exclusion,
2442 struct lttng_bytecode *bytecode,
2443 int wpipe)
2444 {
2445 int ret;
2446 /*
2447 * Copied to ensure proper alignment since 'lsm' is a packed structure.
2448 */
2449 const lttng_domain command_domain = cmd_ctx->lsm.domain;
2450
2451 /*
2452 * The ownership of the following parameters is transferred to
2453 * _cmd_enable_event:
2454 *
2455 * - filter_expression,
2456 * - bytecode,
2457 * - exclusion
2458 */
2459 ret = _cmd_enable_event(cmd_ctx->session,
2460 &command_domain,
2461 cmd_ctx->lsm.u.enable.channel_name, event,
2462 filter_expression, bytecode, exclusion, wpipe, false);
2463 filter_expression = NULL;
2464 bytecode = NULL;
2465 exclusion = NULL;
2466 return ret;
2467 }
2468
2469 /*
2470 * Enable an event which is internal to LTTng. An internal should
2471 * never be made visible to clients and are immune to checks such as
2472 * reserved names.
2473 */
2474 static int cmd_enable_event_internal(struct ltt_session *session,
2475 const struct lttng_domain *domain,
2476 char *channel_name, struct lttng_event *event,
2477 char *filter_expression,
2478 struct lttng_bytecode *filter,
2479 struct lttng_event_exclusion *exclusion,
2480 int wpipe)
2481 {
2482 return _cmd_enable_event(session, domain, channel_name, event,
2483 filter_expression, filter, exclusion, wpipe, true);
2484 }
2485
2486 /*
2487 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2488 */
2489 enum lttng_error_code cmd_list_tracepoints(enum lttng_domain_type domain,
2490 struct lttng_payload *reply_payload)
2491 {
2492 enum lttng_error_code ret_code;
2493 int ret;
2494 ssize_t i, nb_events = 0;
2495 struct lttng_event *events = NULL;
2496 struct lttcomm_list_command_header reply_command_header = {};
2497 size_t reply_command_header_offset;
2498
2499 assert(reply_payload);
2500
2501 /* Reserve space for command reply header. */
2502 reply_command_header_offset = reply_payload->buffer.size;
2503 ret = lttng_dynamic_buffer_set_size(&reply_payload->buffer,
2504 reply_command_header_offset +
2505 sizeof(struct lttcomm_list_command_header));
2506 if (ret) {
2507 ret_code = LTTNG_ERR_NOMEM;
2508 goto error;
2509 }
2510
2511 switch (domain) {
2512 case LTTNG_DOMAIN_KERNEL:
2513 nb_events = kernel_list_events(&events);
2514 if (nb_events < 0) {
2515 ret_code = LTTNG_ERR_KERN_LIST_FAIL;
2516 goto error;
2517 }
2518 break;
2519 case LTTNG_DOMAIN_UST:
2520 nb_events = ust_app_list_events(&events);
2521 if (nb_events < 0) {
2522 ret_code = LTTNG_ERR_UST_LIST_FAIL;
2523 goto error;
2524 }
2525 break;
2526 case LTTNG_DOMAIN_LOG4J:
2527 case LTTNG_DOMAIN_JUL:
2528 case LTTNG_DOMAIN_PYTHON:
2529 nb_events = agent_list_events(&events, domain);
2530 if (nb_events < 0) {
2531 ret_code = LTTNG_ERR_UST_LIST_FAIL;
2532 goto error;
2533 }
2534 break;
2535 default:
2536 ret_code = LTTNG_ERR_UND;
2537 goto error;
2538 }
2539
2540 for (i = 0; i < nb_events; i++) {
2541 ret = lttng_event_serialize(&events[i], 0, NULL, NULL, 0, NULL,
2542 reply_payload);
2543 if (ret) {
2544 ret_code = LTTNG_ERR_NOMEM;
2545 goto error;
2546 }
2547 }
2548
2549 if (nb_events > UINT32_MAX) {
2550 ERR("Tracepoint count would overflow the tracepoint listing command's reply");
2551 ret_code = LTTNG_ERR_OVERFLOW;
2552 goto error;
2553 }
2554
2555 /* Update command reply header. */
2556 reply_command_header.count = (uint32_t) nb_events;
2557 memcpy(reply_payload->buffer.data + reply_command_header_offset, &reply_command_header,
2558 sizeof(reply_command_header));
2559
2560 ret_code = LTTNG_OK;
2561 error:
2562 free(events);
2563 return ret_code;
2564 }
2565
2566 /*
2567 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2568 */
2569 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2570 struct lttng_event_field **fields)
2571 {
2572 int ret;
2573 ssize_t nb_fields = 0;
2574
2575 switch (domain) {
2576 case LTTNG_DOMAIN_UST:
2577 nb_fields = ust_app_list_event_fields(fields);
2578 if (nb_fields < 0) {
2579 ret = LTTNG_ERR_UST_LIST_FAIL;
2580 goto error;
2581 }
2582 break;
2583 case LTTNG_DOMAIN_KERNEL:
2584 default: /* fall-through */
2585 ret = LTTNG_ERR_UND;
2586 goto error;
2587 }
2588
2589 return nb_fields;
2590
2591 error:
2592 /* Return negative value to differentiate return code */
2593 return -ret;
2594 }
2595
2596 enum lttng_error_code cmd_list_syscalls(
2597 struct lttng_payload *reply_payload)
2598 {
2599 enum lttng_error_code ret_code;
2600 ssize_t nb_events, i;
2601 int ret;
2602 struct lttng_event *events = NULL;
2603 struct lttcomm_list_command_header reply_command_header = {};
2604 size_t reply_command_header_offset;
2605
2606 assert(reply_payload);
2607
2608 /* Reserve space for command reply header. */
2609 reply_command_header_offset = reply_payload->buffer.size;
2610 ret = lttng_dynamic_buffer_set_size(&reply_payload->buffer,
2611 reply_command_header_offset +
2612 sizeof(struct lttcomm_list_command_header));
2613 if (ret) {
2614 ret_code = LTTNG_ERR_NOMEM;
2615 goto end;
2616 }
2617
2618 nb_events = syscall_table_list(&events);
2619 if (nb_events < 0) {
2620 ret_code = (enum lttng_error_code) -nb_events;
2621 goto end;
2622 }
2623
2624 for (i = 0; i < nb_events; i++) {
2625 ret = lttng_event_serialize(&events[i], 0, NULL, NULL, 0, NULL,
2626 reply_payload);
2627 if (ret) {
2628 ret_code = LTTNG_ERR_NOMEM;
2629 goto end;
2630 }
2631 }
2632
2633 if (nb_events > UINT32_MAX) {
2634 ERR("Syscall count would overflow the syscall listing command's reply");
2635 ret_code = LTTNG_ERR_OVERFLOW;
2636 goto end;
2637 }
2638
2639 /* Update command reply header. */
2640 reply_command_header.count = (uint32_t) nb_events;
2641 memcpy(reply_payload->buffer.data + reply_command_header_offset, &reply_command_header,
2642 sizeof(reply_command_header));
2643
2644 ret_code = LTTNG_OK;
2645 end:
2646 free(events);
2647 return ret_code;
2648 }
2649
2650 /*
2651 * Command LTTNG_START_TRACE processed by the client thread.
2652 *
2653 * Called with session mutex held.
2654 */
2655 int cmd_start_trace(struct ltt_session *session)
2656 {
2657 enum lttng_error_code ret;
2658 unsigned long nb_chan = 0;
2659 struct ltt_kernel_session *ksession;
2660 struct ltt_ust_session *usess;
2661 const bool session_rotated_after_last_stop =
2662 session->rotated_after_last_stop;
2663 const bool session_cleared_after_last_stop =
2664 session->cleared_after_last_stop;
2665
2666 LTTNG_ASSERT(session);
2667
2668 /* Ease our life a bit ;) */
2669 ksession = session->kernel_session;
2670 usess = session->ust_session;
2671
2672 /* Is the session already started? */
2673 if (session->active) {
2674 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2675 /* Perform nothing */
2676 goto end;
2677 }
2678
2679 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING &&
2680 !session->current_trace_chunk) {
2681 /*
2682 * A rotation was launched while the session was stopped and
2683 * it has not been completed yet. It is not possible to start
2684 * the session since starting the session here would require a
2685 * rotation from "NULL" to a new trace chunk. That rotation
2686 * would overlap with the ongoing rotation, which is not
2687 * supported.
2688 */
2689 WARN("Refusing to start session \"%s\" as a rotation launched after the last \"stop\" is still ongoing",
2690 session->name);
2691 ret = LTTNG_ERR_ROTATION_PENDING;
2692 goto error;
2693 }
2694
2695 /*
2696 * Starting a session without channel is useless since after that it's not
2697 * possible to enable channel thus inform the client.
2698 */
2699 if (usess && usess->domain_global.channels) {
2700 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2701 }
2702 if (ksession) {
2703 nb_chan += ksession->channel_count;
2704 }
2705 if (!nb_chan) {
2706 ret = LTTNG_ERR_NO_CHANNEL;
2707 goto error;
2708 }
2709
2710 session->active = 1;
2711 session->rotated_after_last_stop = false;
2712 session->cleared_after_last_stop = false;
2713 if (session->output_traces && !session->current_trace_chunk) {
2714 if (!session->has_been_started) {
2715 struct lttng_trace_chunk *trace_chunk;
2716
2717 DBG("Creating initial trace chunk of session \"%s\"",
2718 session->name);
2719 trace_chunk = session_create_new_trace_chunk(
2720 session, NULL, NULL, NULL);
2721 if (!trace_chunk) {
2722 ret = LTTNG_ERR_CREATE_DIR_FAIL;
2723 goto error;
2724 }
2725 LTTNG_ASSERT(!session->current_trace_chunk);
2726 ret = (lttng_error_code) session_set_trace_chunk(session, trace_chunk,
2727 NULL);
2728 lttng_trace_chunk_put(trace_chunk);
2729 if (ret) {
2730 ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
2731 goto error;
2732 }
2733 } else {
2734 DBG("Rotating session \"%s\" from its current \"NULL\" trace chunk to a new chunk",
2735 session->name);
2736 /*
2737 * Rotate existing streams into the new chunk.
2738 * This is a "quiet" rotation has no client has
2739 * explicitly requested this operation.
2740 *
2741 * There is also no need to wait for the rotation
2742 * to complete as it will happen immediately. No data
2743 * was produced as the session was stopped, so the
2744 * rotation should happen on reception of the command.
2745 */
2746 ret = (lttng_error_code) cmd_rotate_session(session, NULL, true,
2747 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
2748 if (ret != LTTNG_OK) {
2749 goto error;
2750 }
2751 }
2752 }
2753
2754 /* Kernel tracing */
2755 if (ksession != NULL) {
2756 DBG("Start kernel tracing session %s", session->name);
2757 ret = (lttng_error_code) start_kernel_session(ksession);
2758 if (ret != LTTNG_OK) {
2759 goto error;
2760 }
2761 }
2762
2763 /* Flag session that trace should start automatically */
2764 if (usess) {
2765 int int_ret = ust_app_start_trace_all(usess);
2766
2767 if (int_ret < 0) {
2768 ret = LTTNG_ERR_UST_START_FAIL;
2769 goto error;
2770 }
2771 }
2772
2773 /*
2774 * Open a packet in every stream of the session to ensure that viewers
2775 * can correctly identify the boundaries of the periods during which
2776 * tracing was active for this session.
2777 */
2778 ret = session_open_packets(session);
2779 if (ret != LTTNG_OK) {
2780 goto error;
2781 }
2782
2783 /*
2784 * Clear the flag that indicates that a rotation was done while the
2785 * session was stopped.
2786 */
2787 session->rotated_after_last_stop = false;
2788
2789 if (session->rotate_timer_period) {
2790 int int_ret = timer_session_rotation_schedule_timer_start(
2791 session, session->rotate_timer_period);
2792
2793 if (int_ret < 0) {
2794 ERR("Failed to enable rotate timer");
2795 ret = LTTNG_ERR_UNK;
2796 goto error;
2797 }
2798 }
2799
2800 ret = LTTNG_OK;
2801
2802 error:
2803 if (ret == LTTNG_OK) {
2804 /* Flag this after a successful start. */
2805 session->has_been_started |= 1;
2806 } else {
2807 session->active = 0;
2808 /* Restore initial state on error. */
2809 session->rotated_after_last_stop =
2810 session_rotated_after_last_stop;
2811 session->cleared_after_last_stop =
2812 session_cleared_after_last_stop;
2813 }
2814 end:
2815 return ret;
2816 }
2817
2818 /*
2819 * Command LTTNG_STOP_TRACE processed by the client thread.
2820 */
2821 int cmd_stop_trace(struct ltt_session *session)
2822 {
2823 int ret;
2824 struct ltt_kernel_session *ksession;
2825 struct ltt_ust_session *usess;
2826
2827 LTTNG_ASSERT(session);
2828
2829 DBG("Begin stop session \"%s\" (id %" PRIu64 ")", session->name, session->id);
2830 /* Short cut */
2831 ksession = session->kernel_session;
2832 usess = session->ust_session;
2833
2834 /* Session is not active. Skip everything and inform the client. */
2835 if (!session->active) {
2836 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2837 goto error;
2838 }
2839
2840 ret = stop_kernel_session(ksession);
2841 if (ret != LTTNG_OK) {
2842 goto error;
2843 }
2844
2845 if (usess && usess->active) {
2846 ret = ust_app_stop_trace_all(usess);
2847 if (ret < 0) {
2848 ret = LTTNG_ERR_UST_STOP_FAIL;
2849 goto error;
2850 }
2851 }
2852
2853 DBG("Completed stop session \"%s\" (id %" PRIu64 ")", session->name,
2854 session->id);
2855 /* Flag inactive after a successful stop. */
2856 session->active = 0;
2857 ret = LTTNG_OK;
2858
2859 error:
2860 return ret;
2861 }
2862
2863 /*
2864 * Set the base_path of the session only if subdir of a control uris is set.
2865 * Return LTTNG_OK on success, otherwise LTTNG_ERR_*.
2866 */
2867 static int set_session_base_path_from_uris(struct ltt_session *session,
2868 size_t nb_uri,
2869 struct lttng_uri *uris)
2870 {
2871 int ret;
2872 size_t i;
2873
2874 for (i = 0; i < nb_uri; i++) {
2875 if (uris[i].stype != LTTNG_STREAM_CONTROL ||
2876 uris[i].subdir[0] == '\0') {
2877 /* Not interested in these URIs */
2878 continue;
2879 }
2880
2881 if (session->base_path != NULL) {
2882 free(session->base_path);
2883 session->base_path = NULL;
2884 }
2885
2886 /* Set session base_path */
2887 session->base_path = strdup(uris[i].subdir);
2888 if (!session->base_path) {
2889 PERROR("Failed to copy base path \"%s\" to session \"%s\"",
2890 uris[i].subdir, session->name);
2891 ret = LTTNG_ERR_NOMEM;
2892 goto error;
2893 }
2894 DBG2("Setting base path \"%s\" for session \"%s\"",
2895 session->base_path, session->name);
2896 }
2897 ret = LTTNG_OK;
2898 error:
2899 return ret;
2900 }
2901
2902 /*
2903 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2904 */
2905 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2906 struct lttng_uri *uris)
2907 {
2908 int ret, i;
2909 struct ltt_kernel_session *ksess = session->kernel_session;
2910 struct ltt_ust_session *usess = session->ust_session;
2911
2912 LTTNG_ASSERT(session);
2913 LTTNG_ASSERT(uris);
2914 LTTNG_ASSERT(nb_uri > 0);
2915
2916 /* Can't set consumer URI if the session is active. */
2917 if (session->active) {
2918 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2919 goto error;
2920 }
2921
2922 /*
2923 * Set the session base path if any. This is done inside
2924 * cmd_set_consumer_uri to preserve backward compatibility of the
2925 * previous session creation api vs the session descriptor api.
2926 */
2927 ret = set_session_base_path_from_uris(session, nb_uri, uris);
2928 if (ret != LTTNG_OK) {
2929 goto error;
2930 }
2931
2932 /* Set the "global" consumer URIs */
2933 for (i = 0; i < nb_uri; i++) {
2934 ret = add_uri_to_consumer(session, session->consumer, &uris[i],
2935 LTTNG_DOMAIN_NONE);
2936 if (ret != LTTNG_OK) {
2937 goto error;
2938 }
2939 }
2940
2941 /* Set UST session URIs */
2942 if (session->ust_session) {
2943 for (i = 0; i < nb_uri; i++) {
2944 ret = add_uri_to_consumer(session,
2945 session->ust_session->consumer,
2946 &uris[i], LTTNG_DOMAIN_UST);
2947 if (ret != LTTNG_OK) {
2948 goto error;
2949 }
2950 }
2951 }
2952
2953 /* Set kernel session URIs */
2954 if (session->kernel_session) {
2955 for (i = 0; i < nb_uri; i++) {
2956 ret = add_uri_to_consumer(session,
2957 session->kernel_session->consumer,
2958 &uris[i], LTTNG_DOMAIN_KERNEL);
2959 if (ret != LTTNG_OK) {
2960 goto error;
2961 }
2962 }
2963 }
2964
2965 /*
2966 * Make sure to set the session in output mode after we set URI since a
2967 * session can be created without URL (thus flagged in no output mode).
2968 */
2969 session->output_traces = 1;
2970 if (ksess) {
2971 ksess->output_traces = 1;
2972 }
2973
2974 if (usess) {
2975 usess->output_traces = 1;
2976 }
2977
2978 /* All good! */
2979 ret = LTTNG_OK;
2980
2981 error:
2982 return ret;
2983 }
2984
2985 static
2986 enum lttng_error_code set_session_output_from_descriptor(
2987 struct ltt_session *session,
2988 const struct lttng_session_descriptor *descriptor)
2989 {
2990 int ret;
2991 enum lttng_error_code ret_code = LTTNG_OK;
2992 enum lttng_session_descriptor_type session_type =
2993 lttng_session_descriptor_get_type(descriptor);
2994 enum lttng_session_descriptor_output_type output_type =
2995 lttng_session_descriptor_get_output_type(descriptor);
2996 struct lttng_uri uris[2] = {};
2997 size_t uri_count = 0;
2998
2999 switch (output_type) {
3000 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NONE:
3001 goto end;
3002 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_LOCAL:
3003 lttng_session_descriptor_get_local_output_uri(descriptor,
3004 &uris[0]);
3005 uri_count = 1;
3006 break;
3007 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NETWORK:
3008 lttng_session_descriptor_get_network_output_uris(descriptor,
3009 &uris[0], &uris[1]);
3010 uri_count = 2;
3011 break;
3012 default:
3013 ret_code = LTTNG_ERR_INVALID;
3014 goto end;
3015 }
3016
3017 switch (session_type) {
3018 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
3019 {
3020 struct snapshot_output *new_output = NULL;
3021
3022 new_output = snapshot_output_alloc();
3023 if (!new_output) {
3024 ret_code = LTTNG_ERR_NOMEM;
3025 goto end;
3026 }
3027
3028 ret = snapshot_output_init_with_uri(session,
3029 DEFAULT_SNAPSHOT_MAX_SIZE,
3030 NULL, uris, uri_count, session->consumer,
3031 new_output, &session->snapshot);
3032 if (ret < 0) {
3033 ret_code = (ret == -ENOMEM) ?
3034 LTTNG_ERR_NOMEM : LTTNG_ERR_INVALID;
3035 snapshot_output_destroy(new_output);
3036 goto end;
3037 }
3038 snapshot_add_output(&session->snapshot, new_output);
3039 break;
3040 }
3041 case LTTNG_SESSION_DESCRIPTOR_TYPE_REGULAR:
3042 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3043 {
3044 ret_code = (lttng_error_code) cmd_set_consumer_uri(session, uri_count, uris);
3045 break;
3046 }
3047 default:
3048 ret_code = LTTNG_ERR_INVALID;
3049 goto end;
3050 }
3051 end:
3052 return ret_code;
3053 }
3054
3055 static
3056 enum lttng_error_code cmd_create_session_from_descriptor(
3057 struct lttng_session_descriptor *descriptor,
3058 const lttng_sock_cred *creds,
3059 const char *home_path)
3060 {
3061 int ret;
3062 enum lttng_error_code ret_code;
3063 const char *session_name;
3064 struct ltt_session *new_session = NULL;
3065 enum lttng_session_descriptor_status descriptor_status;
3066
3067 session_lock_list();
3068 if (home_path) {
3069 if (*home_path != '/') {
3070 ERR("Home path provided by client is not absolute");
3071 ret_code = LTTNG_ERR_INVALID;
3072 goto end;
3073 }
3074 }
3075
3076 descriptor_status = lttng_session_descriptor_get_session_name(
3077 descriptor, &session_name);
3078 switch (descriptor_status) {
3079 case LTTNG_SESSION_DESCRIPTOR_STATUS_OK:
3080 break;
3081 case LTTNG_SESSION_DESCRIPTOR_STATUS_UNSET:
3082 session_name = NULL;
3083 break;
3084 default:
3085 ret_code = LTTNG_ERR_INVALID;
3086 goto end;
3087 }
3088
3089 ret_code = session_create(session_name, creds->uid, creds->gid,
3090 &new_session);
3091 if (ret_code != LTTNG_OK) {
3092 goto end;
3093 }
3094
3095 if (!session_name) {
3096 ret = lttng_session_descriptor_set_session_name(descriptor,
3097 new_session->name);
3098 if (ret) {
3099 ret_code = LTTNG_ERR_SESSION_FAIL;
3100 goto end;
3101 }
3102 }
3103
3104 if (!lttng_session_descriptor_is_output_destination_initialized(
3105 descriptor)) {
3106 /*
3107 * Only include the session's creation time in the output
3108 * destination if the name of the session itself was
3109 * not auto-generated.
3110 */
3111 ret_code = lttng_session_descriptor_set_default_output(
3112 descriptor,
3113 session_name ? &new_session->creation_time : NULL,
3114 home_path);
3115 if (ret_code != LTTNG_OK) {
3116 goto end;
3117 }
3118 } else {
3119 new_session->has_user_specified_directory =
3120 lttng_session_descriptor_has_output_directory(
3121 descriptor);
3122 }
3123
3124 switch (lttng_session_descriptor_get_type(descriptor)) {
3125 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
3126 new_session->snapshot_mode = 1;
3127 break;
3128 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3129 new_session->live_timer =
3130 lttng_session_descriptor_live_get_timer_interval(
3131 descriptor);
3132 break;
3133 default:
3134 break;
3135 }
3136
3137 ret_code = set_session_output_from_descriptor(new_session, descriptor);
3138 if (ret_code != LTTNG_OK) {
3139 goto end;
3140 }
3141 new_session->consumer->enabled = 1;
3142 ret_code = LTTNG_OK;
3143 end:
3144 /* Release reference provided by the session_create function. */
3145 session_put(new_session);
3146 if (ret_code != LTTNG_OK && new_session) {
3147 /* Release the global reference on error. */
3148 session_destroy(new_session);
3149 }
3150 session_unlock_list();
3151 return ret_code;
3152 }
3153
3154 enum lttng_error_code cmd_create_session(struct command_ctx *cmd_ctx, int sock,
3155 struct lttng_session_descriptor **return_descriptor)
3156 {
3157 int ret;
3158 size_t payload_size;
3159 struct lttng_dynamic_buffer payload;
3160 struct lttng_buffer_view home_dir_view;
3161 struct lttng_buffer_view session_descriptor_view;
3162 struct lttng_session_descriptor *session_descriptor = NULL;
3163 enum lttng_error_code ret_code;
3164
3165 lttng_dynamic_buffer_init(&payload);
3166 if (cmd_ctx->lsm.u.create_session.home_dir_size >=
3167 LTTNG_PATH_MAX) {
3168 ret_code = LTTNG_ERR_INVALID;
3169 goto error;
3170 }
3171 if (cmd_ctx->lsm.u.create_session.session_descriptor_size >
3172 LTTNG_SESSION_DESCRIPTOR_MAX_LEN) {
3173 ret_code = LTTNG_ERR_INVALID;
3174 goto error;
3175 }
3176
3177 payload_size = cmd_ctx->lsm.u.create_session.home_dir_size +
3178 cmd_ctx->lsm.u.create_session.session_descriptor_size;
3179 ret = lttng_dynamic_buffer_set_size(&payload, payload_size);
3180 if (ret) {
3181 ret_code = LTTNG_ERR_NOMEM;
3182 goto error;
3183 }
3184
3185 ret = lttcomm_recv_unix_sock(sock, payload.data, payload.size);
3186 if (ret <= 0) {
3187 ERR("Reception of session descriptor failed, aborting.");
3188 ret_code = LTTNG_ERR_SESSION_FAIL;
3189 goto error;
3190 }
3191
3192 home_dir_view = lttng_buffer_view_from_dynamic_buffer(
3193 &payload,
3194 0,
3195 cmd_ctx->lsm.u.create_session.home_dir_size);
3196 if (cmd_ctx->lsm.u.create_session.home_dir_size > 0 &&
3197 !lttng_buffer_view_is_valid(&home_dir_view)) {
3198 ERR("Invalid payload in \"create session\" command: buffer too short to contain home directory");
3199 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
3200 goto error;
3201 }
3202
3203 session_descriptor_view = lttng_buffer_view_from_dynamic_buffer(
3204 &payload,
3205 cmd_ctx->lsm.u.create_session.home_dir_size,
3206 cmd_ctx->lsm.u.create_session.session_descriptor_size);
3207 if (!lttng_buffer_view_is_valid(&session_descriptor_view)) {
3208 ERR("Invalid payload in \"create session\" command: buffer too short to contain session descriptor");
3209 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
3210 goto error;
3211 }
3212
3213 ret = lttng_session_descriptor_create_from_buffer(
3214 &session_descriptor_view, &session_descriptor);
3215 if (ret < 0) {
3216 ERR("Failed to create session descriptor from payload of \"create session\" command");
3217 ret_code = LTTNG_ERR_INVALID;
3218 goto error;
3219 }
3220
3221 /*
3222 * Sets the descriptor's auto-generated properties (name, output) if
3223 * needed.
3224 */
3225 ret_code = cmd_create_session_from_descriptor(session_descriptor,
3226 &cmd_ctx->creds,
3227 home_dir_view.size ? home_dir_view.data : NULL);
3228 if (ret_code != LTTNG_OK) {
3229 goto error;
3230 }
3231
3232 ret_code = LTTNG_OK;
3233 *return_descriptor = session_descriptor;
3234 session_descriptor = NULL;
3235 error:
3236 lttng_dynamic_buffer_reset(&payload);
3237 lttng_session_descriptor_destroy(session_descriptor);
3238 return ret_code;
3239 }
3240
3241 static
3242 void cmd_destroy_session_reply(const struct ltt_session *session,
3243 void *_reply_context)
3244 {
3245 int ret;
3246 ssize_t comm_ret;
3247 const struct cmd_destroy_session_reply_context *reply_context =
3248 (cmd_destroy_session_reply_context *) _reply_context;
3249 struct lttng_dynamic_buffer payload;
3250 struct lttcomm_session_destroy_command_header cmd_header;
3251 struct lttng_trace_archive_location *location = NULL;
3252 struct lttcomm_lttng_msg llm = {
3253 .cmd_type = LTTNG_DESTROY_SESSION,
3254 .ret_code = reply_context->destruction_status,
3255 .pid = UINT32_MAX,
3256 .cmd_header_size =
3257 sizeof(struct lttcomm_session_destroy_command_header),
3258 .data_size = 0,
3259 };
3260 size_t payload_size_before_location;
3261
3262 lttng_dynamic_buffer_init(&payload);
3263
3264 ret = lttng_dynamic_buffer_append(&payload, &llm, sizeof(llm));
3265 if (ret) {
3266 ERR("Failed to append session destruction message");
3267 goto error;
3268 }
3269
3270 cmd_header.rotation_state =
3271 (int32_t) (reply_context->implicit_rotation_on_destroy ?
3272 session->rotation_state :
3273 LTTNG_ROTATION_STATE_NO_ROTATION);
3274 ret = lttng_dynamic_buffer_append(&payload, &cmd_header,
3275 sizeof(cmd_header));
3276 if (ret) {
3277 ERR("Failed to append session destruction command header");
3278 goto error;
3279 }
3280
3281 if (!reply_context->implicit_rotation_on_destroy) {
3282 DBG("No implicit rotation performed during the destruction of session \"%s\", sending reply",
3283 session->name);
3284 goto send_reply;
3285 }
3286 if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED) {
3287 DBG("Rotation state of session \"%s\" is not \"completed\", sending session destruction reply",
3288 session->name);
3289 goto send_reply;
3290 }
3291
3292 location = session_get_trace_archive_location(session);
3293 if (!location) {
3294 ERR("Failed to get the location of the trace archive produced during the destruction of session \"%s\"",
3295 session->name);
3296 goto error;
3297 }
3298
3299 payload_size_before_location = payload.size;
3300 comm_ret = lttng_trace_archive_location_serialize(location,
3301 &payload);
3302 lttng_trace_archive_location_put(location);
3303 if (comm_ret < 0) {
3304 ERR("Failed to serialize the location of the trace archive produced during the destruction of session \"%s\"",
3305 session->name);
3306 goto error;
3307 }
3308 /* Update the message to indicate the location's length. */
3309 ((struct lttcomm_lttng_msg *) payload.data)->data_size =
3310 payload.size - payload_size_before_location;
3311 send_reply:
3312 comm_ret = lttcomm_send_unix_sock(reply_context->reply_sock_fd,
3313 payload.data, payload.size);
3314 if (comm_ret != (ssize_t) payload.size) {
3315 ERR("Failed to send result of the destruction of session \"%s\" to client",
3316 session->name);
3317 }
3318 error:
3319 ret = close(reply_context->reply_sock_fd);
3320 if (ret) {
3321 PERROR("Failed to close client socket in deferred session destroy reply");
3322 }
3323 lttng_dynamic_buffer_reset(&payload);
3324 free(_reply_context);
3325 }
3326
3327 /*
3328 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3329 *
3330 * Called with session lock held.
3331 */
3332 int cmd_destroy_session(struct ltt_session *session,
3333 struct notification_thread_handle *notification_thread_handle,
3334 int *sock_fd)
3335 {
3336 int ret;
3337 enum lttng_error_code destruction_last_error = LTTNG_OK;
3338 struct cmd_destroy_session_reply_context *reply_context = NULL;
3339
3340 if (sock_fd) {
3341 reply_context = (cmd_destroy_session_reply_context *) zmalloc(sizeof(*reply_context));
3342 if (!reply_context) {
3343 ret = LTTNG_ERR_NOMEM;
3344 goto end;
3345 }
3346 reply_context->reply_sock_fd = *sock_fd;
3347 }
3348
3349 /* Safety net */
3350 LTTNG_ASSERT(session);
3351
3352 DBG("Begin destroy session %s (id %" PRIu64 ")", session->name,
3353 session->id);
3354 if (session->active) {
3355 DBG("Session \"%s\" is active, attempting to stop it before destroying it",
3356 session->name);
3357 ret = cmd_stop_trace(session);
3358 if (ret != LTTNG_OK && ret != LTTNG_ERR_TRACE_ALREADY_STOPPED) {
3359 /* Carry on with the destruction of the session. */
3360 ERR("Failed to stop session \"%s\" as part of its destruction: %s",
3361 session->name, lttng_strerror(-ret));
3362 destruction_last_error = (lttng_error_code) ret;
3363 }
3364 }
3365
3366 if (session->rotation_schedule_timer_enabled) {
3367 if (timer_session_rotation_schedule_timer_stop(
3368 session)) {
3369 ERR("Failed to stop the \"rotation schedule\" timer of session %s",
3370 session->name);
3371 destruction_last_error = LTTNG_ERR_TIMER_STOP_ERROR;
3372 }
3373 }
3374
3375 if (session->rotate_size) {
3376 unsubscribe_session_consumed_size_rotation(session, notification_thread_handle);
3377 session->rotate_size = 0;
3378 }
3379
3380 if (session->rotated && session->current_trace_chunk && session->output_traces) {
3381 /*
3382 * Perform a last rotation on destruction if rotations have
3383 * occurred during the session's lifetime.
3384 */
3385 ret = cmd_rotate_session(session, NULL, false,
3386 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
3387 if (ret != LTTNG_OK) {
3388 ERR("Failed to perform an implicit rotation as part of the destruction of session \"%s\": %s",
3389 session->name, lttng_strerror(-ret));
3390 destruction_last_error = (lttng_error_code) -ret;
3391 }
3392 if (reply_context) {
3393 reply_context->implicit_rotation_on_destroy = true;
3394 }
3395 } else if (session->has_been_started && session->current_trace_chunk) {
3396 /*
3397 * The user has not triggered a session rotation. However, to
3398 * ensure all data has been consumed, the session is rotated
3399 * to a 'null' trace chunk before it is destroyed.
3400 *
3401 * This is a "quiet" rotation meaning that no notification is
3402 * emitted and no renaming of the current trace chunk takes
3403 * place.
3404 */
3405 ret = cmd_rotate_session(session, NULL, true,
3406 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
3407 /*
3408 * Rotation operations may not be supported by the kernel
3409 * tracer. Hence, do not consider this implicit rotation as
3410 * a session destruction error. The library has already stopped
3411 * the session and waited for pending data; there is nothing
3412 * left to do but complete the destruction of the session.
3413 */
3414 if (ret != LTTNG_OK &&
3415 ret != -LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL) {
3416 ERR("Failed to perform a quiet rotation as part of the destruction of session \"%s\": %s",
3417 session->name, lttng_strerror(ret));
3418 destruction_last_error = (lttng_error_code) -ret;
3419 }
3420 }
3421
3422 if (session->shm_path[0]) {
3423 /*
3424 * When a session is created with an explicit shm_path,
3425 * the consumer daemon will create its shared memory files
3426 * at that location and will *not* unlink them. This is normal
3427 * as the intention of that feature is to make it possible
3428 * to retrieve the content of those files should a crash occur.
3429 *
3430 * To ensure the content of those files can be used, the
3431 * sessiond daemon will replicate the content of the metadata
3432 * cache in a metadata file.
3433 *
3434 * On clean-up, it is expected that the consumer daemon will
3435 * unlink the shared memory files and that the session daemon
3436 * will unlink the metadata file. Then, the session's directory
3437 * in the shm path can be removed.
3438 *
3439 * Unfortunately, a flaw in the design of the sessiond's and
3440 * consumerd's tear down of channels makes it impossible to
3441 * determine when the sessiond _and_ the consumerd have both
3442 * destroyed their representation of a channel. For one, the
3443 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3444 * callbacks in both daemons.
3445 *
3446 * However, it is also impossible for the sessiond to know when
3447 * the consumer daemon is done destroying its channel(s) since
3448 * it occurs as a reaction to the closing of the channel's file
3449 * descriptor. There is no resulting communication initiated
3450 * from the consumerd to the sessiond to confirm that the
3451 * operation is completed (and was successful).
3452 *
3453 * Until this is all fixed, the session daemon checks for the
3454 * removal of the session's shm path which makes it possible
3455 * to safely advertise a session as having been destroyed.
3456 *
3457 * Prior to this fix, it was not possible to reliably save
3458 * a session making use of the --shm-path option, destroy it,
3459 * and load it again. This is because the creation of the
3460 * session would fail upon seeing the session's shm path
3461 * already in existence.
3462 *
3463 * Note that none of the error paths in the check for the
3464 * directory's existence return an error. This is normal
3465 * as there isn't much that can be done. The session will
3466 * be destroyed properly, except that we can't offer the
3467 * guarantee that the same session can be re-created.
3468 */
3469 current_completion_handler = &destroy_completion_handler.handler;
3470 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3471 session->shm_path,
3472 sizeof(destroy_completion_handler.shm_path));
3473 LTTNG_ASSERT(!ret);
3474 }
3475
3476 /*
3477 * The session is destroyed. However, note that the command context
3478 * still holds a reference to the session, thus delaying its destruction
3479 * _at least_ up to the point when that reference is released.
3480 */
3481 session_destroy(session);
3482 if (reply_context) {
3483 reply_context->destruction_status = destruction_last_error;
3484 ret = session_add_destroy_notifier(session,
3485 cmd_destroy_session_reply,
3486 (void *) reply_context);
3487 if (ret) {
3488 ret = LTTNG_ERR_FATAL;
3489 goto end;
3490 } else {
3491 *sock_fd = -1;
3492 }
3493 }
3494 ret = LTTNG_OK;
3495 end:
3496 return ret;
3497 }
3498
3499 /*
3500 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3501 */
3502 int cmd_register_consumer(struct ltt_session *session,
3503 enum lttng_domain_type domain, const char *sock_path,
3504 struct consumer_data *cdata)
3505 {
3506 int ret, sock;
3507 struct consumer_socket *socket = NULL;
3508
3509 LTTNG_ASSERT(session);
3510 LTTNG_ASSERT(cdata);
3511 LTTNG_ASSERT(sock_path);
3512
3513 switch (domain) {
3514 case LTTNG_DOMAIN_KERNEL:
3515 {
3516 struct ltt_kernel_session *ksess = session->kernel_session;
3517
3518 LTTNG_ASSERT(ksess);
3519
3520 /* Can't register a consumer if there is already one */
3521 if (ksess->consumer_fds_sent != 0) {
3522 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3523 goto error;
3524 }
3525
3526 sock = lttcomm_connect_unix_sock(sock_path);
3527 if (sock < 0) {
3528 ret = LTTNG_ERR_CONNECT_FAIL;
3529 goto error;
3530 }
3531 cdata->cmd_sock = sock;
3532
3533 socket = consumer_allocate_socket(&cdata->cmd_sock);
3534 if (socket == NULL) {
3535 ret = close(sock);
3536 if (ret < 0) {
3537 PERROR("close register consumer");
3538 }
3539 cdata->cmd_sock = -1;
3540 ret = LTTNG_ERR_FATAL;
3541 goto error;
3542 }
3543
3544 socket->lock = (pthread_mutex_t *) zmalloc(sizeof(pthread_mutex_t));
3545 if (socket->lock == NULL) {
3546 PERROR("zmalloc pthread mutex");
3547 ret = LTTNG_ERR_FATAL;
3548 goto error;
3549 }
3550 pthread_mutex_init(socket->lock, NULL);
3551 socket->registered = 1;
3552
3553 rcu_read_lock();
3554 consumer_add_socket(socket, ksess->consumer);
3555 rcu_read_unlock();
3556
3557 pthread_mutex_lock(&cdata->pid_mutex);
3558 cdata->pid = -1;
3559 pthread_mutex_unlock(&cdata->pid_mutex);
3560
3561 break;
3562 }
3563 default:
3564 /* TODO: Userspace tracing */
3565 ret = LTTNG_ERR_UND;
3566 goto error;
3567 }
3568
3569 return LTTNG_OK;
3570
3571 error:
3572 if (socket) {
3573 consumer_destroy_socket(socket);
3574 }
3575 return ret;
3576 }
3577
3578 /*
3579 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3580 */
3581 ssize_t cmd_list_domains(struct ltt_session *session,
3582 struct lttng_domain **domains)
3583 {
3584 int ret, index = 0;
3585 ssize_t nb_dom = 0;
3586 struct agent *agt;
3587 struct lttng_ht_iter iter;
3588
3589 if (session->kernel_session != NULL) {
3590 DBG3("Listing domains found kernel domain");
3591 nb_dom++;
3592 }
3593
3594 if (session->ust_session != NULL) {
3595 DBG3("Listing domains found UST global domain");
3596 nb_dom++;
3597
3598 rcu_read_lock();
3599 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3600 agt, node.node) {
3601 if (agt->being_used) {
3602 nb_dom++;
3603 }
3604 }
3605 rcu_read_unlock();
3606 }
3607
3608 if (!nb_dom) {
3609 goto end;
3610 }
3611
3612 *domains = (lttng_domain *) zmalloc(nb_dom * sizeof(struct lttng_domain));
3613 if (*domains == NULL) {
3614 ret = LTTNG_ERR_FATAL;
3615 goto error;
3616 }
3617
3618 if (session->kernel_session != NULL) {
3619 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3620
3621 /* Kernel session buffer type is always GLOBAL */
3622 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3623
3624 index++;
3625 }
3626
3627 if (session->ust_session != NULL) {
3628 (*domains)[index].type = LTTNG_DOMAIN_UST;
3629 (*domains)[index].buf_type = session->ust_session->buffer_type;
3630 index++;
3631
3632 rcu_read_lock();
3633 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3634 agt, node.node) {
3635 if (agt->being_used) {
3636 (*domains)[index].type = agt->domain;
3637 (*domains)[index].buf_type = session->ust_session->buffer_type;
3638 index++;
3639 }
3640 }
3641 rcu_read_unlock();
3642 }
3643 end:
3644 return nb_dom;
3645
3646 error:
3647 /* Return negative value to differentiate return code */
3648 return -ret;
3649 }
3650
3651
3652 /*
3653 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3654 */
3655 enum lttng_error_code cmd_list_channels(enum lttng_domain_type domain,
3656 struct ltt_session *session,
3657 struct lttng_payload *payload)
3658 {
3659 int ret = 0;
3660 unsigned int i = 0;
3661 struct lttcomm_list_command_header cmd_header = {};
3662 size_t cmd_header_offset;
3663 enum lttng_error_code ret_code;
3664
3665 assert(session);
3666 assert(payload);
3667
3668 DBG("Listing channels for session %s", session->name);
3669
3670 cmd_header_offset = payload->buffer.size;
3671
3672 /* Reserve space for command reply header. */
3673 ret = lttng_dynamic_buffer_set_size(&payload->buffer,
3674 cmd_header_offset + sizeof(cmd_header));
3675 if (ret) {
3676 ret_code = LTTNG_ERR_NOMEM;
3677 goto end;
3678 }
3679
3680 switch (domain) {
3681 case LTTNG_DOMAIN_KERNEL:
3682 {
3683 /* Kernel channels */
3684 struct ltt_kernel_channel *kchan;
3685 if (session->kernel_session != NULL) {
3686 cds_list_for_each_entry(kchan,
3687 &session->kernel_session->channel_list.head, list) {
3688 uint64_t discarded_events, lost_packets;
3689 struct lttng_channel_extended *extended;
3690
3691 extended = (struct lttng_channel_extended *)
3692 kchan->channel->attr.extended.ptr;
3693
3694 ret = get_kernel_runtime_stats(session, kchan,
3695 &discarded_events, &lost_packets);
3696 if (ret < 0) {
3697 ret_code = LTTNG_ERR_UNK;
3698 goto end;
3699 }
3700
3701 /*
3702 * Update the discarded_events and lost_packets
3703 * count for the channel
3704 */
3705 extended->discarded_events = discarded_events;
3706 extended->lost_packets = lost_packets;
3707
3708 ret = lttng_channel_serialize(
3709 kchan->channel, &payload->buffer);
3710 if (ret) {
3711 ERR("Failed to serialize lttng_channel: channel name = '%s'",
3712 kchan->channel->name);
3713 ret_code = LTTNG_ERR_UNK;
3714 goto end;
3715 }
3716
3717 i++;
3718 }
3719 }
3720 break;
3721 }
3722 case LTTNG_DOMAIN_UST:
3723 {
3724 struct lttng_ht_iter iter;
3725 struct ltt_ust_channel *uchan;
3726
3727 rcu_read_lock();
3728 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
3729 &iter.iter, uchan, node.node) {
3730 uint64_t discarded_events = 0, lost_packets = 0;
3731 struct lttng_channel *channel = NULL;
3732 struct lttng_channel_extended *extended;
3733
3734 channel = trace_ust_channel_to_lttng_channel(uchan);
3735 if (!channel) {
3736 ret = LTTNG_ERR_NOMEM;
3737 break;
3738 }
3739
3740 extended = (struct lttng_channel_extended *)
3741 channel->attr.extended.ptr;
3742
3743 ret = get_ust_runtime_stats(session, uchan,
3744 &discarded_events, &lost_packets);
3745 if (ret < 0) {
3746 lttng_channel_destroy(channel);
3747 ret_code = LTTNG_ERR_UNK;
3748 break;
3749 }
3750
3751 extended->discarded_events = discarded_events;
3752 extended->lost_packets = lost_packets;
3753
3754 ret = lttng_channel_serialize(
3755 channel, &payload->buffer);
3756 if (ret) {
3757 ERR("Failed to serialize lttng_channel: channel name = '%s'",
3758 channel->name);
3759 ret_code = LTTNG_ERR_UNK;
3760 ret = -1;
3761 break;
3762 }
3763
3764 i++;
3765 }
3766 rcu_read_unlock();
3767 break;
3768 }
3769 default:
3770 break;
3771 }
3772
3773 if (i > UINT32_MAX) {
3774 ERR("Channel count would overflow the channel listing command's reply");
3775 ret_code = LTTNG_ERR_OVERFLOW;
3776 goto end;
3777 }
3778
3779 /* Update command reply header. */
3780 cmd_header.count = (uint32_t) i;
3781 memcpy(payload->buffer.data + cmd_header_offset, &cmd_header,
3782 sizeof(cmd_header));
3783 ret_code = LTTNG_OK;
3784
3785 end:
3786 return ret_code;
3787 }
3788
3789 /*
3790 * Command LTTNG_LIST_EVENTS processed by the client thread.
3791 */
3792 enum lttng_error_code cmd_list_events(enum lttng_domain_type domain,
3793 struct ltt_session *session,
3794 char *channel_name,
3795 struct lttng_payload *reply_payload)
3796 {
3797 int buffer_resize_ret;
3798 enum lttng_error_code ret_code = LTTNG_OK;
3799 struct lttcomm_list_command_header reply_command_header = {};
3800 size_t reply_command_header_offset;
3801 unsigned int nb_events;
3802
3803 assert(reply_payload);
3804
3805 /* Reserve space for command reply header. */
3806 reply_command_header_offset = reply_payload->buffer.size;
3807 buffer_resize_ret = lttng_dynamic_buffer_set_size(&reply_payload->buffer,
3808 reply_command_header_offset +
3809 sizeof(struct lttcomm_list_command_header));
3810 if (buffer_resize_ret) {
3811 ret_code = LTTNG_ERR_NOMEM;
3812 goto end;
3813 }
3814
3815 switch (domain) {
3816 case LTTNG_DOMAIN_KERNEL:
3817 if (session->kernel_session != NULL) {
3818 ret_code = list_lttng_kernel_events(channel_name,
3819 session->kernel_session, reply_payload, &nb_events);
3820 }
3821
3822 break;
3823 case LTTNG_DOMAIN_UST:
3824 {
3825 if (session->ust_session != NULL) {
3826 ret_code = list_lttng_ust_global_events(channel_name,
3827 &session->ust_session->domain_global,
3828 reply_payload, &nb_events);
3829 }
3830
3831 break;
3832 }
3833 case LTTNG_DOMAIN_LOG4J:
3834 case LTTNG_DOMAIN_JUL:
3835 case LTTNG_DOMAIN_PYTHON:
3836 if (session->ust_session) {
3837 struct lttng_ht_iter iter;
3838 struct agent *agt;
3839
3840 rcu_read_lock();
3841 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3842 &iter.iter, agt, node.node) {
3843 if (agt->domain == domain) {
3844 ret_code = list_lttng_agent_events(
3845 agt, reply_payload, &nb_events);
3846 break;
3847 }
3848 }
3849
3850 rcu_read_unlock();
3851 }
3852 break;
3853 default:
3854 ret_code = LTTNG_ERR_UND;
3855 break;
3856 }
3857
3858 if (nb_events > UINT32_MAX) {
3859 ret_code = LTTNG_ERR_OVERFLOW;
3860 goto end;
3861 }
3862
3863 /* Update command reply header. */
3864 reply_command_header.count = (uint32_t) nb_events;
3865 memcpy(reply_payload->buffer.data + reply_command_header_offset, &reply_command_header,
3866 sizeof(reply_command_header));
3867
3868 end:
3869 return ret_code;
3870 }
3871
3872 /*
3873 * Using the session list, filled a lttng_session array to send back to the
3874 * client for session listing.
3875 *
3876 * The session list lock MUST be acquired before calling this function. Use
3877 * session_lock_list() and session_unlock_list().
3878 */
3879 void cmd_list_lttng_sessions(struct lttng_session *sessions,
3880 size_t session_count, uid_t uid, gid_t gid)
3881 {
3882 int ret;
3883 unsigned int i = 0;
3884 struct ltt_session *session;
3885 struct ltt_session_list *list = session_get_list();
3886 struct lttng_session_extended *extended =
3887 (typeof(extended)) (&sessions[session_count]);
3888
3889 DBG("Getting all available session for UID %d GID %d",
3890 uid, gid);
3891 /*
3892 * Iterate over session list and append data after the control struct in
3893 * the buffer.
3894 */
3895 cds_list_for_each_entry(session, &list->head, list) {
3896 if (!session_get(session)) {
3897 continue;
3898 }
3899 /*
3900 * Only list the sessions the user can control.
3901 */
3902 if (!session_access_ok(session, uid) ||
3903 session->destroyed) {
3904 session_put(session);
3905 continue;
3906 }
3907
3908 struct ltt_kernel_session *ksess = session->kernel_session;
3909 struct ltt_ust_session *usess = session->ust_session;
3910
3911 if (session->consumer->type == CONSUMER_DST_NET ||
3912 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3913 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3914 ret = build_network_session_path(sessions[i].path,
3915 sizeof(sessions[i].path), session);
3916 } else {
3917 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3918 session->consumer->dst.session_root_path);
3919 }
3920 if (ret < 0) {
3921 PERROR("snprintf session path");
3922 session_put(session);
3923 continue;
3924 }
3925
3926 strncpy(sessions[i].name, session->name, NAME_MAX);
3927 sessions[i].name[NAME_MAX - 1] = '\0';
3928 sessions[i].enabled = session->active;
3929 sessions[i].snapshot_mode = session->snapshot_mode;
3930 sessions[i].live_timer_interval = session->live_timer;
3931 extended[i].creation_time.value = (uint64_t) session->creation_time;
3932 extended[i].creation_time.is_set = 1;
3933 i++;
3934 session_put(session);
3935 }
3936 }
3937
3938 /*
3939 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3940 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3941 */
3942 int cmd_data_pending(struct ltt_session *session)
3943 {
3944 int ret;
3945 struct ltt_kernel_session *ksess = session->kernel_session;
3946 struct ltt_ust_session *usess = session->ust_session;
3947
3948 LTTNG_ASSERT(session);
3949
3950 DBG("Data pending for session %s", session->name);
3951
3952 /* Session MUST be stopped to ask for data availability. */
3953 if (session->active) {
3954 ret = LTTNG_ERR_SESSION_STARTED;
3955 goto error;
3956 } else {
3957 /*
3958 * If stopped, just make sure we've started before else the above call
3959 * will always send that there is data pending.
3960 *
3961 * The consumer assumes that when the data pending command is received,
3962 * the trace has been started before or else no output data is written
3963 * by the streams which is a condition for data pending. So, this is
3964 * *VERY* important that we don't ask the consumer before a start
3965 * trace.
3966 */
3967 if (!session->has_been_started) {
3968 ret = 0;
3969 goto error;
3970 }
3971 }
3972
3973 /* A rotation is still pending, we have to wait. */
3974 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
3975 DBG("Rotate still pending for session %s", session->name);
3976 ret = 1;
3977 goto error;
3978 }
3979
3980 if (ksess && ksess->consumer) {
3981 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3982 if (ret == 1) {
3983 /* Data is still being extracted for the kernel. */
3984 goto error;
3985 }
3986 }
3987
3988 if (usess && usess->consumer) {
3989 ret = consumer_is_data_pending(usess->id, usess->consumer);
3990 if (ret == 1) {
3991 /* Data is still being extracted for the kernel. */
3992 goto error;
3993 }
3994 }
3995
3996 /* Data is ready to be read by a viewer */
3997 ret = 0;
3998
3999 error:
4000 return ret;
4001 }
4002
4003 /*
4004 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
4005 *
4006 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4007 */
4008 int cmd_snapshot_add_output(struct ltt_session *session,
4009 const struct lttng_snapshot_output *output, uint32_t *id)
4010 {
4011 int ret;
4012 struct snapshot_output *new_output;
4013
4014 LTTNG_ASSERT(session);
4015 LTTNG_ASSERT(output);
4016
4017 DBG("Cmd snapshot add output for session %s", session->name);
4018
4019 /*
4020 * Can't create an output if the session is not set in no-output mode.
4021 */
4022 if (session->output_traces) {
4023 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4024 goto error;
4025 }
4026
4027 if (session->has_non_mmap_channel) {
4028 ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
4029 goto error;
4030 }
4031
4032 /* Only one output is allowed until we have the "tee" feature. */
4033 if (session->snapshot.nb_output == 1) {
4034 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
4035 goto error;
4036 }
4037
4038 new_output = snapshot_output_alloc();
4039 if (!new_output) {
4040 ret = LTTNG_ERR_NOMEM;
4041 goto error;
4042 }
4043
4044 ret = snapshot_output_init(session, output->max_size, output->name,
4045 output->ctrl_url, output->data_url, session->consumer, new_output,
4046 &session->snapshot);
4047 if (ret < 0) {
4048 if (ret == -ENOMEM) {
4049 ret = LTTNG_ERR_NOMEM;
4050 } else {
4051 ret = LTTNG_ERR_INVALID;
4052 }
4053 goto free_error;
4054 }
4055
4056 rcu_read_lock();
4057 snapshot_add_output(&session->snapshot, new_output);
4058 if (id) {
4059 *id = new_output->id;
4060 }
4061 rcu_read_unlock();
4062
4063 return LTTNG_OK;
4064
4065 free_error:
4066 snapshot_output_destroy(new_output);
4067 error:
4068 return ret;
4069 }
4070
4071 /*
4072 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
4073 *
4074 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4075 */
4076 int cmd_snapshot_del_output(struct ltt_session *session,
4077 const struct lttng_snapshot_output *output)
4078 {
4079 int ret;
4080 struct snapshot_output *sout = NULL;
4081
4082 LTTNG_ASSERT(session);
4083 LTTNG_ASSERT(output);
4084
4085 rcu_read_lock();
4086
4087 /*
4088 * Permission denied to create an output if the session is not
4089 * set in no output mode.
4090 */
4091 if (session->output_traces) {
4092 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4093 goto error;
4094 }
4095
4096 if (output->id) {
4097 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
4098 session->name);
4099 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
4100 } else if (*output->name != '\0') {
4101 DBG("Cmd snapshot del output name %s for session %s", output->name,
4102 session->name);
4103 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
4104 }
4105 if (!sout) {
4106 ret = LTTNG_ERR_INVALID;
4107 goto error;
4108 }
4109
4110 snapshot_delete_output(&session->snapshot, sout);
4111 snapshot_output_destroy(sout);
4112 ret = LTTNG_OK;
4113
4114 error:
4115 rcu_read_unlock();
4116 return ret;
4117 }
4118
4119 /*
4120 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
4121 *
4122 * If no output is available, outputs is untouched and 0 is returned.
4123 *
4124 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
4125 */
4126 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
4127 struct lttng_snapshot_output **outputs)
4128 {
4129 int ret, idx = 0;
4130 struct lttng_snapshot_output *list = NULL;
4131 struct lttng_ht_iter iter;
4132 struct snapshot_output *output;
4133
4134 LTTNG_ASSERT(session);
4135 LTTNG_ASSERT(outputs);
4136
4137 DBG("Cmd snapshot list outputs for session %s", session->name);
4138
4139 /*
4140 * Permission denied to create an output if the session is not
4141 * set in no output mode.
4142 */
4143 if (session->output_traces) {
4144 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4145 goto end;
4146 }
4147
4148 if (session->snapshot.nb_output == 0) {
4149 ret = 0;
4150 goto end;
4151 }
4152
4153 list = (lttng_snapshot_output *) zmalloc(session->snapshot.nb_output * sizeof(*list));
4154 if (!list) {
4155 ret = -LTTNG_ERR_NOMEM;
4156 goto end;
4157 }
4158
4159 /* Copy list from session to the new list object. */
4160 rcu_read_lock();
4161 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
4162 output, node.node) {
4163 LTTNG_ASSERT(output->consumer);
4164 list[idx].id = output->id;
4165 list[idx].max_size = output->max_size;
4166 if (lttng_strncpy(list[idx].name, output->name,
4167 sizeof(list[idx].name))) {
4168 ret = -LTTNG_ERR_INVALID;
4169 goto error;
4170 }
4171 if (output->consumer->type == CONSUMER_DST_LOCAL) {
4172 if (lttng_strncpy(list[idx].ctrl_url,
4173 output->consumer->dst.session_root_path,
4174 sizeof(list[idx].ctrl_url))) {
4175 ret = -LTTNG_ERR_INVALID;
4176 goto error;
4177 }
4178 } else {
4179 /* Control URI. */
4180 ret = uri_to_str_url(&output->consumer->dst.net.control,
4181 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
4182 if (ret < 0) {
4183 ret = -LTTNG_ERR_NOMEM;
4184 goto error;
4185 }
4186
4187 /* Data URI. */
4188 ret = uri_to_str_url(&output->consumer->dst.net.data,
4189 list[idx].data_url, sizeof(list[idx].data_url));
4190 if (ret < 0) {
4191 ret = -LTTNG_ERR_NOMEM;
4192 goto error;
4193 }
4194 }
4195 idx++;
4196 }
4197
4198 *outputs = list;
4199 list = NULL;
4200 ret = session->snapshot.nb_output;
4201 error:
4202 rcu_read_unlock();
4203 free(list);
4204 end:
4205 return ret;
4206 }
4207
4208 /*
4209 * Check if we can regenerate the metadata for this session.
4210 * Only kernel, UST per-uid and non-live sessions are supported.
4211 *
4212 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
4213 */
4214 static
4215 int check_regenerate_metadata_support(struct ltt_session *session)
4216 {
4217 int ret;
4218
4219 LTTNG_ASSERT(session);
4220
4221 if (session->live_timer != 0) {
4222 ret = LTTNG_ERR_LIVE_SESSION;
4223 goto end;
4224 }
4225 if (!session->active) {
4226 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4227 goto end;
4228 }
4229 if (session->ust_session) {
4230 switch (session->ust_session->buffer_type) {
4231 case LTTNG_BUFFER_PER_UID:
4232 break;
4233 case LTTNG_BUFFER_PER_PID:
4234 ret = LTTNG_ERR_PER_PID_SESSION;
4235 goto end;
4236 default:
4237 abort();
4238 ret = LTTNG_ERR_UNK;
4239 goto end;
4240 }
4241 }
4242 if (session->consumer->type == CONSUMER_DST_NET &&
4243 session->consumer->relay_minor_version < 8) {
4244 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
4245 goto end;
4246 }
4247 ret = 0;
4248
4249 end:
4250 return ret;
4251 }
4252
4253 static
4254 int clear_metadata_file(int fd)
4255 {
4256 int ret;
4257 off_t lseek_ret;
4258
4259 lseek_ret = lseek(fd, 0, SEEK_SET);
4260 if (lseek_ret < 0) {
4261 PERROR("lseek");
4262 ret = -1;
4263 goto end;
4264 }
4265
4266 ret = ftruncate(fd, 0);
4267 if (ret < 0) {
4268 PERROR("ftruncate");
4269 goto end;
4270 }
4271
4272 end:
4273 return ret;
4274 }
4275
4276 static
4277 int ust_regenerate_metadata(struct ltt_ust_session *usess)
4278 {
4279 int ret = 0;
4280 struct buffer_reg_uid *uid_reg = NULL;
4281 struct buffer_reg_session *session_reg = NULL;
4282
4283 rcu_read_lock();
4284 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
4285 struct ust_registry_session *registry;
4286 struct ust_registry_channel *chan;
4287 struct lttng_ht_iter iter_chan;
4288
4289 session_reg = uid_reg->registry;
4290 registry = session_reg->reg.ust;
4291
4292 pthread_mutex_lock(&registry->lock);
4293 registry->metadata_len_sent = 0;
4294 memset(registry->metadata, 0, registry->metadata_alloc_len);
4295 registry->metadata_len = 0;
4296 registry->metadata_version++;
4297 if (registry->metadata_fd > 0) {
4298 /* Clear the metadata file's content. */
4299 ret = clear_metadata_file(registry->metadata_fd);
4300 if (ret) {
4301 pthread_mutex_unlock(&registry->lock);
4302 goto end;
4303 }
4304 }
4305
4306 ret = ust_metadata_session_statedump(registry, NULL,
4307 registry->major, registry->minor);
4308 if (ret) {
4309 pthread_mutex_unlock(&registry->lock);
4310 ERR("Failed to generate session metadata (err = %d)",
4311 ret);
4312 goto end;
4313 }
4314 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
4315 chan, node.node) {
4316 struct ust_registry_event *event;
4317 struct lttng_ht_iter iter_event;
4318
4319 ret = ust_metadata_channel_statedump(registry, chan);
4320 if (ret) {
4321 pthread_mutex_unlock(&registry->lock);
4322 ERR("Failed to generate channel metadata "
4323 "(err = %d)", ret);
4324 goto end;
4325 }
4326 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
4327 event, node.node) {
4328 ret = ust_metadata_event_statedump(registry,
4329 chan, event);
4330 if (ret) {
4331 pthread_mutex_unlock(&registry->lock);
4332 ERR("Failed to generate event metadata "
4333 "(err = %d)", ret);
4334 goto end;
4335 }
4336 }
4337 }
4338 pthread_mutex_unlock(&registry->lock);
4339 }
4340
4341 end:
4342 rcu_read_unlock();
4343 return ret;
4344 }
4345
4346 /*
4347 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
4348 *
4349 * Ask the consumer to truncate the existing metadata file(s) and
4350 * then regenerate the metadata. Live and per-pid sessions are not
4351 * supported and return an error.
4352 *
4353 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4354 */
4355 int cmd_regenerate_metadata(struct ltt_session *session)
4356 {
4357 int ret;
4358
4359 LTTNG_ASSERT(session);
4360
4361 ret = check_regenerate_metadata_support(session);
4362 if (ret) {
4363 goto end;
4364 }
4365
4366 if (session->kernel_session) {
4367 ret = kernctl_session_regenerate_metadata(
4368 session->kernel_session->fd);
4369 if (ret < 0) {
4370 ERR("Failed to regenerate the kernel metadata");
4371 goto end;
4372 }
4373 }
4374
4375 if (session->ust_session) {
4376 ret = ust_regenerate_metadata(session->ust_session);
4377 if (ret < 0) {
4378 ERR("Failed to regenerate the UST metadata");
4379 goto end;
4380 }
4381 }
4382 DBG("Cmd metadata regenerate for session %s", session->name);
4383 ret = LTTNG_OK;
4384
4385 end:
4386 return ret;
4387 }
4388
4389 /*
4390 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
4391 *
4392 * Ask the tracer to regenerate a new statedump.
4393 *
4394 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4395 */
4396 int cmd_regenerate_statedump(struct ltt_session *session)
4397 {
4398 int ret;
4399
4400 LTTNG_ASSERT(session);
4401
4402 if (!session->active) {
4403 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4404 goto end;
4405 }
4406
4407 if (session->kernel_session) {
4408 ret = kernctl_session_regenerate_statedump(
4409 session->kernel_session->fd);
4410 /*
4411 * Currently, the statedump in kernel can only fail if out
4412 * of memory.
4413 */
4414 if (ret < 0) {
4415 if (ret == -ENOMEM) {
4416 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
4417 } else {
4418 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4419 }
4420 ERR("Failed to regenerate the kernel statedump");
4421 goto end;
4422 }
4423 }
4424
4425 if (session->ust_session) {
4426 ret = ust_app_regenerate_statedump_all(session->ust_session);
4427 /*
4428 * Currently, the statedump in UST always returns 0.
4429 */
4430 if (ret < 0) {
4431 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4432 ERR("Failed to regenerate the UST statedump");
4433 goto end;
4434 }
4435 }
4436 DBG("Cmd regenerate statedump for session %s", session->name);
4437 ret = LTTNG_OK;
4438
4439 end:
4440 return ret;
4441 }
4442
4443 static
4444 enum lttng_error_code synchronize_tracer_notifier_register(
4445 struct notification_thread_handle *notification_thread,
4446 struct lttng_trigger *trigger, const struct lttng_credentials *cmd_creds)
4447 {
4448 enum lttng_error_code ret_code;
4449 const struct lttng_condition *condition =
4450 lttng_trigger_get_const_condition(trigger);
4451 const char *trigger_name;
4452 uid_t trigger_owner;
4453 enum lttng_trigger_status trigger_status;
4454 const enum lttng_domain_type trigger_domain =
4455 lttng_trigger_get_underlying_domain_type_restriction(
4456 trigger);
4457
4458 trigger_status = lttng_trigger_get_owner_uid(trigger, &trigger_owner);
4459 LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
4460
4461 LTTNG_ASSERT(condition);
4462 LTTNG_ASSERT(lttng_condition_get_type(condition) ==
4463 LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES);
4464
4465 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
4466 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ?
4467 trigger_name : "(anonymous)";
4468
4469 session_lock_list();
4470 switch (trigger_domain) {
4471 case LTTNG_DOMAIN_KERNEL:
4472 {
4473 ret_code = kernel_register_event_notifier(trigger, cmd_creds);
4474 if (ret_code != LTTNG_OK) {
4475 enum lttng_error_code notif_thread_unregister_ret;
4476
4477 notif_thread_unregister_ret =
4478 notification_thread_command_unregister_trigger(
4479 notification_thread, trigger);
4480
4481 if (notif_thread_unregister_ret != LTTNG_OK) {
4482 /* Return the original error code. */
4483 ERR("Failed to unregister trigger from notification thread during error recovery: trigger name = '%s', trigger owner uid = %d, error code = %d",
4484 trigger_name,
4485 (int) trigger_owner,
4486 ret_code);
4487 }
4488 }
4489 break;
4490 }
4491 case LTTNG_DOMAIN_UST:
4492 ust_app_global_update_all_event_notifier_rules();
4493 break;
4494 case LTTNG_DOMAIN_JUL:
4495 case LTTNG_DOMAIN_LOG4J:
4496 case LTTNG_DOMAIN_PYTHON:
4497 {
4498 /* Agent domains. */
4499 struct agent *agt = agent_find_by_event_notifier_domain(
4500 trigger_domain);
4501
4502 if (!agt) {
4503 agt = agent_create(trigger_domain);
4504 if (!agt) {
4505 ret_code = LTTNG_ERR_NOMEM;
4506 goto end_unlock_session_list;
4507 }
4508
4509 agent_add(agt, the_trigger_agents_ht_by_domain);
4510 }
4511
4512 ret_code = (lttng_error_code) trigger_agent_enable(trigger, agt);
4513 if (ret_code != LTTNG_OK) {
4514 goto end_unlock_session_list;
4515 }
4516
4517 break;
4518 }
4519 case LTTNG_DOMAIN_NONE:
4520 default:
4521 abort();
4522 }
4523
4524 ret_code = LTTNG_OK;
4525 end_unlock_session_list:
4526 session_unlock_list();
4527 return ret_code;
4528 }
4529
4530 enum lttng_error_code cmd_register_trigger(const struct lttng_credentials *cmd_creds,
4531 struct lttng_trigger *trigger,
4532 bool is_trigger_anonymous,
4533 struct notification_thread_handle *notification_thread,
4534 struct lttng_trigger **return_trigger)
4535 {
4536 enum lttng_error_code ret_code;
4537 const char *trigger_name;
4538 uid_t trigger_owner;
4539 enum lttng_trigger_status trigger_status;
4540
4541 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
4542 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ?
4543 trigger_name : "(anonymous)";
4544
4545 trigger_status = lttng_trigger_get_owner_uid(
4546 trigger, &trigger_owner);
4547 LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
4548
4549 DBG("Running register trigger command: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4550 trigger_name, (int) trigger_owner,
4551 (int) lttng_credentials_get_uid(cmd_creds));
4552
4553 /*
4554 * Validate the trigger credentials against the command credentials.
4555 * Only the root user can register a trigger with non-matching
4556 * credentials.
4557 */
4558 if (!lttng_credentials_is_equal_uid(
4559 lttng_trigger_get_credentials(trigger),
4560 cmd_creds)) {
4561 if (lttng_credentials_get_uid(cmd_creds) != 0) {
4562 ERR("Trigger credentials do not match the command credentials: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4563 trigger_name, (int) trigger_owner,
4564 (int) lttng_credentials_get_uid(cmd_creds));
4565 ret_code = LTTNG_ERR_INVALID_TRIGGER;
4566 goto end;
4567 }
4568 }
4569
4570 /*
4571 * The bytecode generation also serves as a validation step for the
4572 * bytecode expressions.
4573 */
4574 ret_code = lttng_trigger_generate_bytecode(trigger, cmd_creds);
4575 if (ret_code != LTTNG_OK) {
4576 ERR("Failed to generate bytecode of trigger: trigger name = '%s', trigger owner uid = %d, error code = %d",
4577 trigger_name, (int) trigger_owner, ret_code);
4578 goto end;
4579 }
4580
4581 /*
4582 * A reference to the trigger is acquired by the notification thread.
4583 * It is safe to return the same trigger to the caller since it the
4584 * other user holds a reference.
4585 *
4586 * The trigger is modified during the execution of the
4587 * "register trigger" command. However, by the time the command returns,
4588 * it is safe to use without any locking as its properties are
4589 * immutable.
4590 */
4591 ret_code = notification_thread_command_register_trigger(
4592 notification_thread, trigger, is_trigger_anonymous);
4593 if (ret_code != LTTNG_OK) {
4594 DBG("Failed to register trigger to notification thread: trigger name = '%s', trigger owner uid = %d, error code = %d",
4595 trigger_name, (int) trigger_owner, ret_code);
4596 goto end;
4597 }
4598
4599 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
4600 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ?
4601 trigger_name : "(anonymous)";
4602
4603 /*
4604 * Synchronize tracers if the trigger adds an event notifier.
4605 */
4606 if (lttng_trigger_needs_tracer_notifier(trigger)) {
4607 ret_code = synchronize_tracer_notifier_register(notification_thread,
4608 trigger, cmd_creds);
4609 if (ret_code != LTTNG_OK) {
4610 ERR("Error registering tracer notifier: %s",
4611 lttng_strerror(-ret_code));
4612 goto end;
4613 }
4614 }
4615
4616 /*
4617 * Return an updated trigger to the client.
4618 *
4619 * Since a modified version of the same trigger is returned, acquire a
4620 * reference to the trigger so the caller doesn't have to care if those
4621 * are distinct instances or not.
4622 */
4623 if (ret_code == LTTNG_OK) {
4624 lttng_trigger_get(trigger);
4625 *return_trigger = trigger;
4626 /* Ownership of trigger was transferred to caller. */
4627 trigger = NULL;
4628 }
4629 end:
4630 return ret_code;
4631 }
4632
4633 static
4634 enum lttng_error_code synchronize_tracer_notifier_unregister(
4635 const struct lttng_trigger *trigger)
4636 {
4637 enum lttng_error_code ret_code;
4638 const struct lttng_condition *condition =
4639 lttng_trigger_get_const_condition(trigger);
4640 const enum lttng_domain_type trigger_domain =
4641 lttng_trigger_get_underlying_domain_type_restriction(
4642 trigger);
4643
4644 LTTNG_ASSERT(condition);
4645 LTTNG_ASSERT(lttng_condition_get_type(condition) ==
4646 LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES);
4647
4648 session_lock_list();
4649 switch (trigger_domain) {
4650 case LTTNG_DOMAIN_KERNEL:
4651 ret_code = kernel_unregister_event_notifier(trigger);
4652 if (ret_code != LTTNG_OK) {
4653 goto end_unlock_session_list;
4654 }
4655
4656 break;
4657 case LTTNG_DOMAIN_UST:
4658 ust_app_global_update_all_event_notifier_rules();
4659 break;
4660 case LTTNG_DOMAIN_JUL:
4661 case LTTNG_DOMAIN_LOG4J:
4662 case LTTNG_DOMAIN_PYTHON:
4663 {
4664 /* Agent domains. */
4665 struct agent *agt = agent_find_by_event_notifier_domain(
4666 trigger_domain);
4667
4668 /*
4669 * This trigger was never registered in the first place. Calling
4670 * this function under those circumstances is an internal error.
4671 */
4672 LTTNG_ASSERT(agt);
4673 ret_code = (lttng_error_code) trigger_agent_disable(trigger, agt);
4674 if (ret_code != LTTNG_OK) {
4675 goto end_unlock_session_list;
4676 }
4677
4678 break;
4679 }
4680 case LTTNG_DOMAIN_NONE:
4681 default:
4682 abort();
4683 }
4684
4685 ret_code = LTTNG_OK;
4686
4687 end_unlock_session_list:
4688 session_unlock_list();
4689 return ret_code;
4690 }
4691
4692 enum lttng_error_code cmd_unregister_trigger(const struct lttng_credentials *cmd_creds,
4693 const struct lttng_trigger *trigger,
4694 struct notification_thread_handle *notification_thread)
4695 {
4696 enum lttng_error_code ret_code;
4697 const char *trigger_name;
4698 uid_t trigger_owner;
4699 enum lttng_trigger_status trigger_status;
4700 struct lttng_trigger *sessiond_trigger = NULL;
4701
4702 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
4703 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ? trigger_name : "(anonymous)";
4704 trigger_status = lttng_trigger_get_owner_uid(trigger, &trigger_owner);
4705 LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
4706
4707 DBG("Running unregister trigger command: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4708 trigger_name, (int) trigger_owner,
4709 (int) lttng_credentials_get_uid(cmd_creds));
4710
4711 /*
4712 * Validate the trigger credentials against the command credentials.
4713 * Only the root user can unregister a trigger with non-matching
4714 * credentials.
4715 */
4716 if (!lttng_credentials_is_equal_uid(
4717 lttng_trigger_get_credentials(trigger),
4718 cmd_creds)) {
4719 if (lttng_credentials_get_uid(cmd_creds) != 0) {
4720 ERR("Trigger credentials do not match the command credentials: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4721 trigger_name, (int) trigger_owner,
4722 (int) lttng_credentials_get_uid(cmd_creds));
4723 ret_code = LTTNG_ERR_INVALID_TRIGGER;
4724 goto end;
4725 }
4726 }
4727
4728 /* Fetch the sessiond side trigger object. */
4729 ret_code = notification_thread_command_get_trigger(
4730 notification_thread, trigger, &sessiond_trigger);
4731 if (ret_code != LTTNG_OK) {
4732 DBG("Failed to get trigger from notification thread during unregister: trigger name = '%s', trigger owner uid = %d, error code = %d",
4733 trigger_name, (int) trigger_owner, ret_code);
4734 goto end;
4735 }
4736
4737 LTTNG_ASSERT(sessiond_trigger);
4738
4739 /*
4740 * From this point on, no matter what, consider the trigger
4741 * unregistered.
4742 *
4743 * We set the unregistered state of the sessiond side trigger object in
4744 * the client thread since we want to minimize the possibility of the
4745 * notification thread being stalled due to a long execution of an
4746 * action that required the trigger lock.
4747 */
4748 lttng_trigger_set_as_unregistered(sessiond_trigger);
4749
4750 ret_code = notification_thread_command_unregister_trigger(notification_thread,
4751 trigger);
4752 if (ret_code != LTTNG_OK) {
4753 DBG("Failed to unregister trigger from notification thread: trigger name = '%s', trigger owner uid = %d, error code = %d",
4754 trigger_name, (int) trigger_owner, ret_code);
4755 goto end;
4756 }
4757
4758 /*
4759 * Synchronize tracers if the trigger removes an event notifier.
4760 * Do this even if the trigger unregistration failed to at least stop
4761 * the tracers from producing notifications associated with this
4762 * event notifier.
4763 */
4764 if (lttng_trigger_needs_tracer_notifier(trigger)) {
4765 ret_code = synchronize_tracer_notifier_unregister(trigger);
4766 if (ret_code != LTTNG_OK) {
4767 ERR("Error unregistering trigger to tracer.");
4768 goto end;
4769 }
4770
4771 }
4772
4773 end:
4774 lttng_trigger_put(sessiond_trigger);
4775 return ret_code;
4776 }
4777
4778 enum lttng_error_code cmd_list_triggers(struct command_ctx *cmd_ctx,
4779 struct notification_thread_handle *notification_thread,
4780 struct lttng_triggers **return_triggers)
4781 {
4782 int ret;
4783 enum lttng_error_code ret_code;
4784 struct lttng_triggers *triggers = NULL;
4785
4786 /* Get the set of triggers from the notification thread. */
4787 ret_code = notification_thread_command_list_triggers(
4788 notification_thread, cmd_ctx->creds.uid, &triggers);
4789 if (ret_code != LTTNG_OK) {
4790 goto end;
4791 }
4792
4793 ret = lttng_triggers_remove_hidden_triggers(triggers);
4794 if (ret) {
4795 ret_code = LTTNG_ERR_UNK;
4796 goto end;
4797 }
4798
4799 *return_triggers = triggers;
4800 triggers = NULL;
4801 ret_code = LTTNG_OK;
4802 end:
4803 lttng_triggers_destroy(triggers);
4804 return ret_code;
4805 }
4806
4807 enum lttng_error_code cmd_execute_error_query(const struct lttng_credentials *cmd_creds,
4808 const struct lttng_error_query *query,
4809 struct lttng_error_query_results **_results,
4810 struct notification_thread_handle *notification_thread)
4811 {
4812 enum lttng_error_code ret_code;
4813 const struct lttng_trigger *query_target_trigger;
4814 const struct lttng_action *query_target_action = NULL;
4815 struct lttng_trigger *matching_trigger = NULL;
4816 const char *trigger_name;
4817 uid_t trigger_owner;
4818 enum lttng_trigger_status trigger_status;
4819 struct lttng_error_query_results *results = NULL;
4820
4821 switch (lttng_error_query_get_target_type(query)) {
4822 case LTTNG_ERROR_QUERY_TARGET_TYPE_TRIGGER:
4823 query_target_trigger = lttng_error_query_trigger_borrow_target(query);
4824 break;
4825 case LTTNG_ERROR_QUERY_TARGET_TYPE_CONDITION:
4826 query_target_trigger =
4827 lttng_error_query_condition_borrow_target(query);
4828 break;
4829 case LTTNG_ERROR_QUERY_TARGET_TYPE_ACTION:
4830 query_target_trigger = lttng_error_query_action_borrow_trigger_target(
4831 query);
4832 break;
4833 default:
4834 abort();
4835 }
4836
4837 LTTNG_ASSERT(query_target_trigger);
4838
4839 ret_code = notification_thread_command_get_trigger(notification_thread,
4840 query_target_trigger, &matching_trigger);
4841 if (ret_code != LTTNG_OK) {
4842 goto end;
4843 }
4844
4845 /* No longer needed. */
4846 query_target_trigger = NULL;
4847
4848 if (lttng_error_query_get_target_type(query) ==
4849 LTTNG_ERROR_QUERY_TARGET_TYPE_ACTION) {
4850 /* Get the sessiond-side version of the target action. */
4851 query_target_action =
4852 lttng_error_query_action_borrow_action_target(
4853 query, matching_trigger);
4854 }
4855
4856 trigger_status = lttng_trigger_get_name(matching_trigger, &trigger_name);
4857 trigger_name = trigger_status == LTTNG_TRIGGER_STATUS_OK ?
4858 trigger_name : "(anonymous)";
4859 trigger_status = lttng_trigger_get_owner_uid(matching_trigger,
4860 &trigger_owner);
4861 LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
4862
4863 results = lttng_error_query_results_create();
4864 if (!results) {
4865 ret_code = LTTNG_ERR_NOMEM;
4866 goto end;
4867 }
4868
4869 DBG("Running \"execute error query\" command: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4870 trigger_name, (int) trigger_owner,
4871 (int) lttng_credentials_get_uid(cmd_creds));
4872
4873 /*
4874 * Validate the trigger credentials against the command credentials.
4875 * Only the root user can target a trigger with non-matching
4876 * credentials.
4877 */
4878 if (!lttng_credentials_is_equal_uid(
4879 lttng_trigger_get_credentials(matching_trigger),
4880 cmd_creds)) {
4881 if (lttng_credentials_get_uid(cmd_creds) != 0) {
4882 ERR("Trigger credentials do not match the command credentials: trigger name = '%s', trigger owner uid = %d, command creds uid = %d",
4883 trigger_name, (int) trigger_owner,
4884 (int) lttng_credentials_get_uid(cmd_creds));
4885 ret_code = LTTNG_ERR_INVALID_TRIGGER;
4886 goto end;
4887 }
4888 }
4889
4890 switch (lttng_error_query_get_target_type(query)) {
4891 case LTTNG_ERROR_QUERY_TARGET_TYPE_TRIGGER:
4892 trigger_status = lttng_trigger_add_error_results(
4893 matching_trigger, results);
4894
4895 switch (trigger_status) {
4896 case LTTNG_TRIGGER_STATUS_OK:
4897 break;
4898 default:
4899 ret_code = LTTNG_ERR_UNK;
4900 goto end;
4901 }
4902
4903 break;
4904 case LTTNG_ERROR_QUERY_TARGET_TYPE_CONDITION:
4905 {
4906 trigger_status = lttng_trigger_condition_add_error_results(
4907 matching_trigger, results);
4908
4909 switch (trigger_status) {
4910 case LTTNG_TRIGGER_STATUS_OK:
4911 break;
4912 default:
4913 ret_code = LTTNG_ERR_UNK;
4914 goto end;
4915 }
4916
4917 break;
4918 }
4919 case LTTNG_ERROR_QUERY_TARGET_TYPE_ACTION:
4920 {
4921 const enum lttng_action_status action_status =
4922 lttng_action_add_error_query_results(
4923 query_target_action, results);
4924
4925 switch (action_status) {
4926 case LTTNG_ACTION_STATUS_OK:
4927 break;
4928 default:
4929 ret_code = LTTNG_ERR_UNK;
4930 goto end;
4931 }
4932
4933 break;
4934 }
4935 default:
4936 abort();
4937 break;
4938 }
4939
4940 *_results = results;
4941 results = NULL;
4942 ret_code = LTTNG_OK;
4943 end:
4944 lttng_trigger_put(matching_trigger);
4945 lttng_error_query_results_destroy(results);
4946 return ret_code;
4947 }
4948
4949 /*
4950 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4951 * snapshot output is *not* set with a remote destination.
4952 *
4953 * Return LTTNG_OK on success or a LTTNG_ERR code.
4954 */
4955 static enum lttng_error_code set_relayd_for_snapshot(
4956 struct consumer_output *output,
4957 const struct ltt_session *session)
4958 {
4959 enum lttng_error_code status = LTTNG_OK;
4960 struct lttng_ht_iter iter;
4961 struct consumer_socket *socket;
4962 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
4963 const char *base_path;
4964
4965 LTTNG_ASSERT(output);
4966 LTTNG_ASSERT(session);
4967
4968 DBG2("Set relayd object from snapshot output");
4969
4970 if (session->current_trace_chunk) {
4971 enum lttng_trace_chunk_status chunk_status =
4972 lttng_trace_chunk_get_id(
4973 session->current_trace_chunk,
4974 &current_chunk_id.value);
4975
4976 if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK) {
4977 current_chunk_id.is_set = true;
4978 } else {
4979 ERR("Failed to get current trace chunk id");
4980 status = LTTNG_ERR_UNK;
4981 goto error;
4982 }
4983 }
4984
4985 /* Ignore if snapshot consumer output is not network. */
4986 if (output->type != CONSUMER_DST_NET) {
4987 goto error;
4988 }
4989
4990 /*
4991 * The snapshot record URI base path overrides the session
4992 * base path.
4993 */
4994 if (output->dst.net.control.subdir[0] != '\0') {
4995 base_path = output->dst.net.control.subdir;
4996 } else {
4997 base_path = session->base_path;
4998 }
4999
5000 /*
5001 * For each consumer socket, create and send the relayd object of the
5002 * snapshot output.
5003 */
5004 rcu_read_lock();
5005 cds_lfht_for_each_entry(output->socks->ht, &iter.iter,
5006 socket, node.node) {
5007 pthread_mutex_lock(socket->lock);
5008 status = send_consumer_relayd_sockets(LTTNG_DOMAIN_NONE, session->id,
5009 output, socket,
5010 session->name, session->hostname,
5011 base_path,
5012 session->live_timer,
5013 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
5014 session->creation_time,
5015 session->name_contains_creation_time);
5016 pthread_mutex_unlock(socket->lock);
5017 if (status != LTTNG_OK) {
5018 rcu_read_unlock();
5019 goto error;
5020 }
5021 }
5022 rcu_read_unlock();
5023
5024 error:
5025 return status;
5026 }
5027
5028 /*
5029 * Record a kernel snapshot.
5030 *
5031 * Return LTTNG_OK on success or a LTTNG_ERR code.
5032 */
5033 static enum lttng_error_code record_kernel_snapshot(
5034 struct ltt_kernel_session *ksess,
5035 const struct consumer_output *output,
5036 const struct ltt_session *session,
5037 int wait, uint64_t nb_packets_per_stream)
5038 {
5039 enum lttng_error_code status;
5040
5041 LTTNG_ASSERT(ksess);
5042 LTTNG_ASSERT(output);
5043 LTTNG_ASSERT(session);
5044
5045 status = kernel_snapshot_record(
5046 ksess, output, wait, nb_packets_per_stream);
5047 return status;
5048 }
5049
5050 /*
5051 * Record a UST snapshot.
5052 *
5053 * Returns LTTNG_OK on success or a LTTNG_ERR error code.
5054 */
5055 static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
5056 const struct consumer_output *output,
5057 const struct ltt_session *session,
5058 int wait, uint64_t nb_packets_per_stream)
5059 {
5060 enum lttng_error_code status;
5061
5062 LTTNG_ASSERT(usess);
5063 LTTNG_ASSERT(output);
5064 LTTNG_ASSERT(session);
5065
5066 status = ust_app_snapshot_record(
5067 usess, output, wait, nb_packets_per_stream);
5068 return status;
5069 }
5070
5071 static
5072 uint64_t get_session_size_one_more_packet_per_stream(
5073 const struct ltt_session *session, uint64_t cur_nr_packets)
5074 {
5075 uint64_t tot_size = 0;
5076
5077 if (session->kernel_session) {
5078 struct ltt_kernel_channel *chan;
5079 const struct ltt_kernel_session *ksess =
5080 session->kernel_session;
5081
5082 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
5083 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
5084 /*
5085 * Don't take channel into account if we
5086 * already grab all its packets.
5087 */
5088 continue;
5089 }
5090 tot_size += chan->channel->attr.subbuf_size
5091 * chan->stream_count;
5092 }
5093 }
5094
5095 if (session->ust_session) {
5096 const struct ltt_ust_session *usess = session->ust_session;
5097
5098 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
5099 cur_nr_packets);
5100 }
5101
5102 return tot_size;
5103 }
5104
5105 /*
5106 * Calculate the number of packets we can grab from each stream that
5107 * fits within the overall snapshot max size.
5108 *
5109 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
5110 * the number of packets per stream.
5111 *
5112 * TODO: this approach is not perfect: we consider the worse case
5113 * (packet filling the sub-buffers) as an upper bound, but we could do
5114 * better if we do this calculation while we actually grab the packet
5115 * content: we would know how much padding we don't actually store into
5116 * the file.
5117 *
5118 * This algorithm is currently bounded by the number of packets per
5119 * stream.
5120 *
5121 * Since we call this algorithm before actually grabbing the data, it's
5122 * an approximation: for instance, applications could appear/disappear
5123 * in between this call and actually grabbing data.
5124 */
5125 static
5126 int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
5127 uint64_t max_size)
5128 {
5129 int64_t size_left;
5130 uint64_t cur_nb_packets = 0;
5131
5132 if (!max_size) {
5133 return 0; /* Infinite */
5134 }
5135
5136 size_left = max_size;
5137 for (;;) {
5138 uint64_t one_more_packet_tot_size;
5139
5140 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(
5141 session, cur_nb_packets);
5142 if (!one_more_packet_tot_size) {
5143 /* We are already grabbing all packets. */
5144 break;
5145 }
5146 size_left -= one_more_packet_tot_size;
5147 if (size_left < 0) {
5148 break;
5149 }
5150 cur_nb_packets++;
5151 }
5152 if (!cur_nb_packets && size_left != max_size) {
5153 /* Not enough room to grab one packet of each stream, error. */
5154 return -1;
5155 }
5156 return cur_nb_packets;
5157 }
5158
5159 static
5160 enum lttng_error_code snapshot_record(struct ltt_session *session,
5161 const struct snapshot_output *snapshot_output, int wait)
5162 {
5163 int64_t nb_packets_per_stream;
5164 char snapshot_chunk_name[LTTNG_NAME_MAX];
5165 int ret;
5166 enum lttng_error_code ret_code = LTTNG_OK;
5167 struct lttng_trace_chunk *snapshot_trace_chunk;
5168 struct consumer_output *original_ust_consumer_output = NULL;
5169 struct consumer_output *original_kernel_consumer_output = NULL;
5170 struct consumer_output *snapshot_ust_consumer_output = NULL;
5171 struct consumer_output *snapshot_kernel_consumer_output = NULL;
5172
5173 ret = snprintf(snapshot_chunk_name, sizeof(snapshot_chunk_name),
5174 "%s-%s-%" PRIu64,
5175 snapshot_output->name,
5176 snapshot_output->datetime,
5177 snapshot_output->nb_snapshot);
5178 if (ret < 0 || ret >= sizeof(snapshot_chunk_name)) {
5179 ERR("Failed to format snapshot name");
5180 ret_code = LTTNG_ERR_INVALID;
5181 goto error;
5182 }
5183 DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
5184 snapshot_output->name, session->name,
5185 snapshot_chunk_name);
5186 if (!session->kernel_session && !session->ust_session) {
5187 ERR("Failed to record snapshot as no channels exist");
5188 ret_code = LTTNG_ERR_NO_CHANNEL;
5189 goto error;
5190 }
5191
5192 if (session->kernel_session) {
5193 original_kernel_consumer_output =
5194 session->kernel_session->consumer;
5195 snapshot_kernel_consumer_output =
5196 consumer_copy_output(snapshot_output->consumer);
5197 strcpy(snapshot_kernel_consumer_output->chunk_path,
5198 snapshot_chunk_name);
5199
5200 /* Copy the original domain subdir. */
5201 strcpy(snapshot_kernel_consumer_output->domain_subdir,
5202 original_kernel_consumer_output->domain_subdir);
5203
5204 ret = consumer_copy_sockets(snapshot_kernel_consumer_output,
5205 original_kernel_consumer_output);
5206 if (ret < 0) {
5207 ERR("Failed to copy consumer sockets from snapshot output configuration");
5208 ret_code = LTTNG_ERR_NOMEM;
5209 goto error;
5210 }
5211 ret_code = set_relayd_for_snapshot(
5212 snapshot_kernel_consumer_output, session);
5213 if (ret_code != LTTNG_OK) {
5214 ERR("Failed to setup relay daemon for kernel tracer snapshot");
5215 goto error;
5216 }
5217 session->kernel_session->consumer =
5218 snapshot_kernel_consumer_output;
5219 }
5220 if (session->ust_session) {
5221 original_ust_consumer_output = session->ust_session->consumer;
5222 snapshot_ust_consumer_output =
5223 consumer_copy_output(snapshot_output->consumer);
5224 strcpy(snapshot_ust_consumer_output->chunk_path,
5225 snapshot_chunk_name);
5226
5227 /* Copy the original domain subdir. */
5228 strcpy(snapshot_ust_consumer_output->domain_subdir,
5229 original_ust_consumer_output->domain_subdir);
5230
5231 ret = consumer_copy_sockets(snapshot_ust_consumer_output,
5232 original_ust_consumer_output);
5233 if (ret < 0) {
5234 ERR("Failed to copy consumer sockets from snapshot output configuration");
5235 ret_code = LTTNG_ERR_NOMEM;
5236 goto error;
5237 }
5238 ret_code = set_relayd_for_snapshot(
5239 snapshot_ust_consumer_output, session);
5240 if (ret_code != LTTNG_OK) {
5241 ERR("Failed to setup relay daemon for userspace tracer snapshot");
5242 goto error;
5243 }
5244 session->ust_session->consumer =
5245 snapshot_ust_consumer_output;
5246 }
5247
5248 snapshot_trace_chunk = session_create_new_trace_chunk(session,
5249 snapshot_kernel_consumer_output ?:
5250 snapshot_ust_consumer_output,
5251 consumer_output_get_base_path(
5252 snapshot_output->consumer),
5253 snapshot_chunk_name);
5254 if (!snapshot_trace_chunk) {
5255 ERR("Failed to create temporary trace chunk to record a snapshot of session \"%s\"",
5256 session->name);
5257 ret_code = LTTNG_ERR_CREATE_DIR_FAIL;
5258 goto error;
5259 }
5260 LTTNG_ASSERT(!session->current_trace_chunk);
5261 ret = session_set_trace_chunk(session, snapshot_trace_chunk, NULL);
5262 lttng_trace_chunk_put(snapshot_trace_chunk);
5263 snapshot_trace_chunk = NULL;
5264 if (ret) {
5265 ERR("Failed to set temporary trace chunk to record a snapshot of session \"%s\"",
5266 session->name);
5267 ret_code = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
5268 goto error;
5269 }
5270
5271 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
5272 snapshot_output->max_size);
5273 if (nb_packets_per_stream < 0) {
5274 ret_code = LTTNG_ERR_MAX_SIZE_INVALID;
5275 goto error_close_trace_chunk;
5276 }
5277
5278 if (session->kernel_session) {
5279 ret_code = record_kernel_snapshot(session->kernel_session,
5280 snapshot_kernel_consumer_output, session,
5281 wait, nb_packets_per_stream);
5282 if (ret_code != LTTNG_OK) {
5283 goto error_close_trace_chunk;
5284 }
5285 }
5286
5287 if (session->ust_session) {
5288 ret_code = record_ust_snapshot(session->ust_session,
5289 snapshot_ust_consumer_output, session,
5290 wait, nb_packets_per_stream);
5291 if (ret_code != LTTNG_OK) {
5292 goto error_close_trace_chunk;
5293 }
5294 }
5295
5296 error_close_trace_chunk:
5297 if (session_set_trace_chunk(session, NULL, &snapshot_trace_chunk)) {
5298 ERR("Failed to release the current trace chunk of session \"%s\"",
5299 session->name);
5300 ret_code = LTTNG_ERR_UNK;
5301 }
5302
5303 if (session_close_trace_chunk(session, snapshot_trace_chunk,
5304 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION, NULL)) {
5305 /*
5306 * Don't goto end; make sure the chunk is closed for the session
5307 * to allow future snapshots.
5308 */
5309 ERR("Failed to close snapshot trace chunk of session \"%s\"",
5310 session->name);
5311 ret_code = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5312 }
5313
5314 lttng_trace_chunk_put(snapshot_trace_chunk);
5315 snapshot_trace_chunk = NULL;
5316 error:
5317 if (original_ust_consumer_output) {
5318 session->ust_session->consumer = original_ust_consumer_output;
5319 }
5320 if (original_kernel_consumer_output) {
5321 session->kernel_session->consumer =
5322 original_kernel_consumer_output;
5323 }
5324 consumer_output_put(snapshot_ust_consumer_output);
5325 consumer_output_put(snapshot_kernel_consumer_output);
5326 return ret_code;
5327 }
5328
5329 /*
5330 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
5331 *
5332 * The wait parameter is ignored so this call always wait for the snapshot to
5333 * complete before returning.
5334 *
5335 * Return LTTNG_OK on success or else a LTTNG_ERR code.
5336 */
5337 int cmd_snapshot_record(struct ltt_session *session,
5338 const struct lttng_snapshot_output *output, int wait)
5339 {
5340 enum lttng_error_code cmd_ret = LTTNG_OK;
5341 int ret;
5342 unsigned int snapshot_success = 0;
5343 char datetime[16];
5344 struct snapshot_output *tmp_output = NULL;
5345
5346 LTTNG_ASSERT(session);
5347 LTTNG_ASSERT(output);
5348
5349 DBG("Cmd snapshot record for session %s", session->name);
5350
5351 /* Get the datetime for the snapshot output directory. */
5352 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
5353 sizeof(datetime));
5354 if (!ret) {
5355 cmd_ret = LTTNG_ERR_INVALID;
5356 goto error;
5357 }
5358
5359 /*
5360 * Permission denied to create an output if the session is not
5361 * set in no output mode.
5362 */
5363 if (session->output_traces) {
5364 cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
5365 goto error;
5366 }
5367
5368 /* The session needs to be started at least once. */
5369 if (!session->has_been_started) {
5370 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
5371 goto error;
5372 }
5373
5374 /* Use temporary output for the session. */
5375 if (*output->ctrl_url != '\0') {
5376 tmp_output = snapshot_output_alloc();
5377 if (!tmp_output) {
5378 cmd_ret = LTTNG_ERR_NOMEM;
5379 goto error;
5380 }
5381
5382 ret = snapshot_output_init(session, output->max_size,
5383 output->name,
5384 output->ctrl_url, output->data_url,
5385 session->consumer,
5386 tmp_output, NULL);
5387 if (ret < 0) {
5388 if (ret == -ENOMEM) {
5389 cmd_ret = LTTNG_ERR_NOMEM;
5390 } else {
5391 cmd_ret = LTTNG_ERR_INVALID;
5392 }
5393 goto error;
5394 }
5395 /* Use the global session count for the temporary snapshot. */
5396 tmp_output->nb_snapshot = session->snapshot.nb_snapshot;
5397
5398 /* Use the global datetime */
5399 memcpy(tmp_output->datetime, datetime, sizeof(datetime));
5400 cmd_ret = snapshot_record(session, tmp_output, wait);
5401 if (cmd_ret != LTTNG_OK) {
5402 goto error;
5403 }
5404 snapshot_success = 1;
5405 } else {
5406 struct snapshot_output *sout;
5407 struct lttng_ht_iter iter;
5408
5409 rcu_read_lock();
5410 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
5411 &iter.iter, sout, node.node) {
5412 struct snapshot_output output_copy;
5413
5414 /*
5415 * Make a local copy of the output and override output
5416 * parameters with those provided as part of the
5417 * command.
5418 */
5419 memcpy(&output_copy, sout, sizeof(output_copy));
5420
5421 if (output->max_size != (uint64_t) -1ULL) {
5422 output_copy.max_size = output->max_size;
5423 }
5424
5425 output_copy.nb_snapshot = session->snapshot.nb_snapshot;
5426 memcpy(output_copy.datetime, datetime,
5427 sizeof(datetime));
5428
5429 /* Use temporary name. */
5430 if (*output->name != '\0') {
5431 if (lttng_strncpy(output_copy.name,
5432 output->name,
5433 sizeof(output_copy.name))) {
5434 cmd_ret = LTTNG_ERR_INVALID;
5435 rcu_read_unlock();
5436 goto error;
5437 }
5438 }
5439
5440 cmd_ret = snapshot_record(session, &output_copy, wait);
5441 if (cmd_ret != LTTNG_OK) {
5442 rcu_read_unlock();
5443 goto error;
5444 }
5445 snapshot_success = 1;
5446 }
5447 rcu_read_unlock();
5448 }
5449
5450 if (snapshot_success) {
5451 session->snapshot.nb_snapshot++;
5452 } else {
5453 cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
5454 }
5455
5456 error:
5457 if (tmp_output) {
5458 snapshot_output_destroy(tmp_output);
5459 }
5460 return cmd_ret;
5461 }
5462
5463 /*
5464 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
5465 */
5466 int cmd_set_session_shm_path(struct ltt_session *session,
5467 const char *shm_path)
5468 {
5469 /* Safety net */
5470 LTTNG_ASSERT(session);
5471
5472 /*
5473 * Can only set shm path before session is started.
5474 */
5475 if (session->has_been_started) {
5476 return LTTNG_ERR_SESSION_STARTED;
5477 }
5478
5479 strncpy(session->shm_path, shm_path,
5480 sizeof(session->shm_path));
5481 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
5482
5483 return LTTNG_OK;
5484 }
5485
5486 /*
5487 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
5488 *
5489 * Ask the consumer to rotate the session output directory.
5490 * The session lock must be held.
5491 *
5492 * Returns LTTNG_OK on success or else a negative LTTng error code.
5493 */
5494 int cmd_rotate_session(struct ltt_session *session,
5495 struct lttng_rotate_session_return *rotate_return,
5496 bool quiet_rotation,
5497 enum lttng_trace_chunk_command_type command)
5498 {
5499 int ret;
5500 uint64_t ongoing_rotation_chunk_id;
5501 enum lttng_error_code cmd_ret = LTTNG_OK;
5502 struct lttng_trace_chunk *chunk_being_archived = NULL;
5503 struct lttng_trace_chunk *new_trace_chunk = NULL;
5504 enum lttng_trace_chunk_status chunk_status;
5505 bool failed_to_rotate = false;
5506 enum lttng_error_code rotation_fail_code = LTTNG_OK;
5507
5508 LTTNG_ASSERT(session);
5509
5510 if (!session->has_been_started) {
5511 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
5512 goto end;
5513 }
5514
5515 /*
5516 * Explicit rotation is not supported for live sessions.
5517 * However, live sessions can perform a quiet rotation on
5518 * destroy.
5519 * Rotation is not supported for snapshot traces (no output).
5520 */
5521 if ((!quiet_rotation && session->live_timer) ||
5522 !session->output_traces) {
5523 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5524 goto end;
5525 }
5526
5527 /* Unsupported feature in lttng-relayd before 2.11. */
5528 if (!quiet_rotation && session->consumer->type == CONSUMER_DST_NET &&
5529 (session->consumer->relay_major_version == 2 &&
5530 session->consumer->relay_minor_version < 11)) {
5531 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
5532 goto end;
5533 }
5534
5535 /* Unsupported feature in lttng-modules before 2.8 (lack of sequence number). */
5536 if (session->kernel_session && !kernel_supports_ring_buffer_packet_sequence_number()) {
5537 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL;
5538 goto end;
5539 }
5540
5541 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
5542 DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
5543 session->name);
5544 cmd_ret = LTTNG_ERR_ROTATION_PENDING;
5545 goto end;
5546 }
5547
5548 /*
5549 * After a stop, we only allow one rotation to occur, the other ones are
5550 * useless until a new start.
5551 */
5552 if (session->rotated_after_last_stop) {
5553 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
5554 session->name);
5555 cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
5556 goto end;
5557 }
5558
5559 /*
5560 * After a stop followed by a clear, disallow following rotations a they would
5561 * generate empty chunks.
5562 */
5563 if (session->cleared_after_last_stop) {
5564 DBG("Session \"%s\" was already cleared after stop, refusing rotation",
5565 session->name);
5566 cmd_ret = LTTNG_ERR_ROTATION_AFTER_STOP_CLEAR;
5567 goto end;
5568 }
5569
5570 if (session->active) {
5571 new_trace_chunk = session_create_new_trace_chunk(session, NULL,
5572 NULL, NULL);
5573 if (!new_trace_chunk) {
5574 cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
5575 goto error;
5576 }
5577 }
5578
5579 /*
5580 * The current trace chunk becomes the chunk being archived.
5581 *
5582 * After this point, "chunk_being_archived" must absolutely
5583 * be closed on the consumer(s), otherwise it will never be
5584 * cleaned-up, which will result in a leak.
5585 */
5586 ret = session_set_trace_chunk(session, new_trace_chunk,
5587 &chunk_being_archived);
5588 if (ret) {
5589 cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
5590 goto error;
5591 }
5592
5593 if (session->kernel_session) {
5594 cmd_ret = kernel_rotate_session(session);
5595 if (cmd_ret != LTTNG_OK) {
5596 failed_to_rotate = true;
5597 rotation_fail_code = cmd_ret;
5598 }
5599 }
5600 if (session->ust_session) {
5601 cmd_ret = ust_app_rotate_session(session);
5602 if (cmd_ret != LTTNG_OK) {
5603 failed_to_rotate = true;
5604 rotation_fail_code = cmd_ret;
5605 }
5606 }
5607
5608 if (!session->active) {
5609 session->rotated_after_last_stop = true;
5610 }
5611
5612 if (!chunk_being_archived) {
5613 DBG("Rotating session \"%s\" from a \"NULL\" trace chunk to a new trace chunk, skipping completion check",
5614 session->name);
5615 if (failed_to_rotate) {
5616 cmd_ret = rotation_fail_code;
5617 goto error;
5618 }
5619 cmd_ret = LTTNG_OK;
5620 goto end;
5621 }
5622
5623 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
5624 chunk_status = lttng_trace_chunk_get_id(chunk_being_archived,
5625 &ongoing_rotation_chunk_id);
5626 LTTNG_ASSERT(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5627
5628 ret = session_close_trace_chunk(session, chunk_being_archived,
5629 command, session->last_chunk_path);
5630 if (ret) {
5631 cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5632 goto error;
5633 }
5634
5635 if (failed_to_rotate) {
5636 cmd_ret = rotation_fail_code;
5637 goto error;
5638 }
5639
5640 session->quiet_rotation = quiet_rotation;
5641 ret = timer_session_rotation_pending_check_start(session,
5642 DEFAULT_ROTATE_PENDING_TIMER);
5643 if (ret) {
5644 cmd_ret = LTTNG_ERR_UNK;
5645 goto error;
5646 }
5647
5648 if (rotate_return) {
5649 rotate_return->rotation_id = ongoing_rotation_chunk_id;
5650 }
5651
5652 session->chunk_being_archived = chunk_being_archived;
5653 chunk_being_archived = NULL;
5654 if (!quiet_rotation) {
5655 ret = notification_thread_command_session_rotation_ongoing(
5656 the_notification_thread_handle, session->name,
5657 session->uid, session->gid,
5658 ongoing_rotation_chunk_id);
5659 if (ret != LTTNG_OK) {
5660 ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
5661 session->name);
5662 cmd_ret = (lttng_error_code) ret;
5663 }
5664 }
5665
5666 DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
5667 session->name, ongoing_rotation_chunk_id);
5668 end:
5669 lttng_trace_chunk_put(new_trace_chunk);
5670 lttng_trace_chunk_put(chunk_being_archived);
5671 ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
5672 return ret;
5673 error:
5674 if (session_reset_rotation_state(session,
5675 LTTNG_ROTATION_STATE_ERROR)) {
5676 ERR("Failed to reset rotation state of session \"%s\"",
5677 session->name);
5678 }
5679 goto end;
5680 }
5681
5682 /*
5683 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
5684 *
5685 * Check if the session has finished its rotation.
5686 *
5687 * Return LTTNG_OK on success or else an LTTNG_ERR code.
5688 */
5689 int cmd_rotate_get_info(struct ltt_session *session,
5690 struct lttng_rotation_get_info_return *info_return,
5691 uint64_t rotation_id)
5692 {
5693 enum lttng_error_code cmd_ret = LTTNG_OK;
5694 enum lttng_rotation_state rotation_state;
5695
5696 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
5697 session->most_recent_chunk_id.value);
5698
5699 if (session->chunk_being_archived) {
5700 enum lttng_trace_chunk_status chunk_status;
5701 uint64_t chunk_id;
5702
5703 chunk_status = lttng_trace_chunk_get_id(
5704 session->chunk_being_archived,
5705 &chunk_id);
5706 LTTNG_ASSERT(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5707
5708 rotation_state = rotation_id == chunk_id ?
5709 LTTNG_ROTATION_STATE_ONGOING :
5710 LTTNG_ROTATION_STATE_EXPIRED;
5711 } else {
5712 if (session->last_archived_chunk_id.is_set &&
5713 rotation_id != session->last_archived_chunk_id.value) {
5714 rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
5715 } else {
5716 rotation_state = session->rotation_state;
5717 }
5718 }
5719
5720 switch (rotation_state) {
5721 case LTTNG_ROTATION_STATE_NO_ROTATION:
5722 DBG("Reporting that no rotation has occurred within the lifetime of session \"%s\"",
5723 session->name);
5724 goto end;
5725 case LTTNG_ROTATION_STATE_EXPIRED:
5726 DBG("Reporting that the rotation state of rotation id %" PRIu64 " of session \"%s\" has expired",
5727 rotation_id, session->name);
5728 break;
5729 case LTTNG_ROTATION_STATE_ONGOING:
5730 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
5731 rotation_id, session->name);
5732 break;
5733 case LTTNG_ROTATION_STATE_COMPLETED:
5734 {
5735 int fmt_ret;
5736 char *chunk_path;
5737 char *current_tracing_path_reply;
5738 size_t current_tracing_path_reply_len;
5739
5740 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
5741 rotation_id, session->name);
5742
5743 switch (session_get_consumer_destination_type(session)) {
5744 case CONSUMER_DST_LOCAL:
5745 current_tracing_path_reply =
5746 info_return->location.local.absolute_path;
5747 current_tracing_path_reply_len =
5748 sizeof(info_return->location.local.absolute_path);
5749 info_return->location_type =
5750 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
5751 fmt_ret = asprintf(&chunk_path,
5752 "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
5753 session_get_base_path(session),
5754 session->last_archived_chunk_name);
5755 if (fmt_ret == -1) {
5756 PERROR("Failed to format the path of the last archived trace chunk");
5757 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5758 cmd_ret = LTTNG_ERR_UNK;
5759 goto end;
5760 }
5761 break;
5762 case CONSUMER_DST_NET:
5763 {
5764 uint16_t ctrl_port, data_port;
5765
5766 current_tracing_path_reply =
5767 info_return->location.relay.relative_path;
5768 current_tracing_path_reply_len =
5769 sizeof(info_return->location.relay.relative_path);
5770 /* Currently the only supported relay protocol. */
5771 info_return->location.relay.protocol =
5772 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
5773
5774 fmt_ret = lttng_strncpy(info_return->location.relay.host,
5775 session_get_net_consumer_hostname(session),
5776 sizeof(info_return->location.relay.host));
5777 if (fmt_ret) {
5778 ERR("Failed to copy host name to rotate_get_info reply");
5779 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5780 cmd_ret = LTTNG_ERR_SET_URL;
5781 goto end;
5782 }
5783
5784 session_get_net_consumer_ports(session, &ctrl_port, &data_port);
5785 info_return->location.relay.ports.control = ctrl_port;
5786 info_return->location.relay.ports.data = data_port;
5787 info_return->location_type =
5788 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
5789 chunk_path = strdup(session->last_chunk_path);
5790 if (!chunk_path) {
5791 ERR("Failed to allocate the path of the last archived trace chunk");
5792 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5793 cmd_ret = LTTNG_ERR_UNK;
5794 goto end;
5795 }
5796 break;
5797 }
5798 default:
5799 abort();
5800 }
5801
5802 fmt_ret = lttng_strncpy(current_tracing_path_reply,
5803 chunk_path, current_tracing_path_reply_len);
5804 free(chunk_path);
5805 if (fmt_ret) {
5806 ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
5807 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5808 cmd_ret = LTTNG_ERR_UNK;
5809 goto end;
5810 }
5811
5812 break;
5813 }
5814 case LTTNG_ROTATION_STATE_ERROR:
5815 DBG("Reporting that an error occurred during rotation %" PRIu64 " of session \"%s\"",
5816 rotation_id, session->name);
5817 break;
5818 default:
5819 abort();
5820 }
5821
5822 cmd_ret = LTTNG_OK;
5823 end:
5824 info_return->status = (int32_t) rotation_state;
5825 return cmd_ret;
5826 }
5827
5828 /*
5829 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
5830 *
5831 * Configure the automatic rotation parameters.
5832 * 'activate' to true means activate the rotation schedule type with 'new_value'.
5833 * 'activate' to false means deactivate the rotation schedule and validate that
5834 * 'new_value' has the same value as the currently active value.
5835 *
5836 * Return LTTNG_OK on success or else a positive LTTNG_ERR code.
5837 */
5838 int cmd_rotation_set_schedule(struct ltt_session *session,
5839 bool activate, enum lttng_rotation_schedule_type schedule_type,
5840 uint64_t new_value,
5841 struct notification_thread_handle *notification_thread_handle)
5842 {
5843 int ret;
5844 uint64_t *parameter_value;
5845
5846 LTTNG_ASSERT(session);
5847
5848 DBG("Cmd rotate set schedule session %s", session->name);
5849
5850 if (session->live_timer || !session->output_traces) {
5851 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
5852 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5853 goto end;
5854 }
5855
5856 switch (schedule_type) {
5857 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5858 parameter_value = &session->rotate_size;
5859 break;
5860 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5861 parameter_value = &session->rotate_timer_period;
5862 if (new_value >= UINT_MAX) {
5863 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
5864 new_value, UINT_MAX);
5865 ret = LTTNG_ERR_INVALID;
5866 goto end;
5867 }
5868 break;
5869 default:
5870 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
5871 ret = LTTNG_ERR_INVALID;
5872 goto end;
5873 }
5874
5875 /* Improper use of the API. */
5876 if (new_value == -1ULL) {
5877 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
5878 ret = LTTNG_ERR_INVALID;
5879 goto end;
5880 }
5881
5882 /*
5883 * As indicated in struct ltt_session's comments, a value of == 0 means
5884 * this schedule rotation type is not in use.
5885 *
5886 * Reject the command if we were asked to activate a schedule that was
5887 * already active.
5888 */
5889 if (activate && *parameter_value != 0) {
5890 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
5891 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
5892 goto end;
5893 }
5894
5895 /*
5896 * Reject the command if we were asked to deactivate a schedule that was
5897 * not active.
5898 */
5899 if (!activate && *parameter_value == 0) {
5900 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
5901 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5902 goto end;
5903 }
5904
5905 /*
5906 * Reject the command if we were asked to deactivate a schedule that
5907 * doesn't exist.
5908 */
5909 if (!activate && *parameter_value != new_value) {
5910 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
5911 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5912 goto end;
5913 }
5914
5915 *parameter_value = activate ? new_value : 0;
5916
5917 switch (schedule_type) {
5918 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5919 if (activate && session->active) {
5920 /*
5921 * Only start the timer if the session is active,
5922 * otherwise it will be started when the session starts.
5923 */
5924 ret = timer_session_rotation_schedule_timer_start(
5925 session, new_value);
5926 if (ret) {
5927 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
5928 ret = LTTNG_ERR_UNK;
5929 goto end;
5930 }
5931 } else {
5932 ret = timer_session_rotation_schedule_timer_stop(
5933 session);
5934 if (ret) {
5935 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
5936 ret = LTTNG_ERR_UNK;
5937 goto end;
5938 }
5939 }
5940 break;
5941 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5942 if (activate) {
5943 ret = subscribe_session_consumed_size_rotation(session,
5944 new_value, notification_thread_handle);
5945 if (ret) {
5946 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
5947 ret = LTTNG_ERR_UNK;
5948 goto end;
5949 }
5950 } else {
5951 ret = unsubscribe_session_consumed_size_rotation(session,
5952 notification_thread_handle);
5953 if (ret) {
5954 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
5955 ret = LTTNG_ERR_UNK;
5956 goto end;
5957 }
5958
5959 }
5960 break;
5961 default:
5962 /* Would have been caught before. */
5963 abort();
5964 }
5965
5966 ret = LTTNG_OK;
5967
5968 goto end;
5969
5970 end:
5971 return ret;
5972 }
5973
5974 /* Wait for a given path to be removed before continuing. */
5975 static enum lttng_error_code wait_on_path(void *path_data)
5976 {
5977 const char *shm_path = (const char *) path_data;
5978
5979 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5980 shm_path);
5981 while (true) {
5982 int ret;
5983 struct stat st;
5984
5985 ret = stat(shm_path, &st);
5986 if (ret) {
5987 if (errno != ENOENT) {
5988 PERROR("stat() returned an error while checking for the existence of the shm path");
5989 } else {
5990 DBG("shm path no longer exists, completing the destruction of session");
5991 }
5992 break;
5993 } else {
5994 if (!S_ISDIR(st.st_mode)) {
5995 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5996 shm_path);
5997 break;
5998 }
5999 }
6000 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
6001 }
6002 return LTTNG_OK;
6003 }
6004
6005 /*
6006 * Returns a pointer to a handler to run on completion of a command.
6007 * Returns NULL if no handler has to be run for the last command executed.
6008 */
6009 const struct cmd_completion_handler *cmd_pop_completion_handler(void)
6010 {
6011 struct cmd_completion_handler *handler = current_completion_handler;
6012
6013 current_completion_handler = NULL;
6014 return handler;
6015 }
6016
6017 /*
6018 * Init command subsystem.
6019 */
6020 void cmd_init(void)
6021 {
6022 /*
6023 * Set network sequence index to 1 for streams to match a relayd
6024 * socket on the consumer side.
6025 */
6026 pthread_mutex_lock(&relayd_net_seq_idx_lock);
6027 relayd_net_seq_idx = 1;
6028 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
6029
6030 DBG("Command subsystem initialized");
6031 }
LTTng 2.0 tools and control repository
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