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Fix: sessiond: snapshot: leak of trace chunk
[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c
1 /*
2 * Copyright (C) 2012 David Goulet <dgoulet@efficios.com>
3 * Copyright (C) 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 *
5 * SPDX-License-Identifier: GPL-2.0-only
6 *
7 */
8
9 #include "bin/lttng-sessiond/tracker.h"
10 #include "lttng/lttng-error.h"
11 #include "lttng/tracker.h"
12 #define _LGPL_SOURCE
13 #include <assert.h>
14 #include <inttypes.h>
15 #include <urcu/list.h>
16 #include <urcu/uatomic.h>
17 #include <sys/stat.h>
18 #include <stdio.h>
19
20 #include <common/defaults.h>
21 #include <common/common.h>
22 #include <common/sessiond-comm/sessiond-comm.h>
23 #include <common/relayd/relayd.h>
24 #include <common/utils.h>
25 #include <common/compat/string.h>
26 #include <common/kernel-ctl/kernel-ctl.h>
27 #include <common/dynamic-buffer.h>
28 #include <common/buffer-view.h>
29 #include <common/trace-chunk.h>
30 #include <lttng/location-internal.h>
31 #include <lttng/trigger/trigger-internal.h>
32 #include <lttng/condition/condition.h>
33 #include <lttng/action/action.h>
34 #include <lttng/channel.h>
35 #include <lttng/channel-internal.h>
36 #include <lttng/rotate-internal.h>
37 #include <lttng/location-internal.h>
38 #include <lttng/session-internal.h>
39 #include <lttng/userspace-probe-internal.h>
40 #include <lttng/session-descriptor-internal.h>
41 #include <common/string-utils/string-utils.h>
42
43 #include "channel.h"
44 #include "consumer.h"
45 #include "event.h"
46 #include "health-sessiond.h"
47 #include "kernel.h"
48 #include "kernel-consumer.h"
49 #include "lttng-sessiond.h"
50 #include "utils.h"
51 #include "lttng-syscall.h"
52 #include "agent.h"
53 #include "buffer-registry.h"
54 #include "notification-thread.h"
55 #include "notification-thread-commands.h"
56 #include "rotate.h"
57 #include "rotation-thread.h"
58 #include "timer.h"
59 #include "agent-thread.h"
60
61 #include "cmd.h"
62
63 /* Sleep for 100ms between each check for the shm path's deletion. */
64 #define SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US 100000
65
66 struct cmd_destroy_session_reply_context {
67 int reply_sock_fd;
68 bool implicit_rotation_on_destroy;
69 /*
70 * Indicates whether or not an error occurred while launching the
71 * destruction of a session.
72 */
73 enum lttng_error_code destruction_status;
74 };
75
76 static enum lttng_error_code wait_on_path(void *path);
77
78 /*
79 * Command completion handler that is used by the destroy command
80 * when a session that has a non-default shm_path is being destroyed.
81 *
82 * See comment in cmd_destroy_session() for the rationale.
83 */
84 static struct destroy_completion_handler {
85 struct cmd_completion_handler handler;
86 char shm_path[member_sizeof(struct ltt_session, shm_path)];
87 } destroy_completion_handler = {
88 .handler = {
89 .run = wait_on_path,
90 .data = destroy_completion_handler.shm_path
91 },
92 .shm_path = { 0 },
93 };
94
95 static struct cmd_completion_handler *current_completion_handler;
96
97 /*
98 * Used to keep a unique index for each relayd socket created where this value
99 * is associated with streams on the consumer so it can match the right relayd
100 * to send to. It must be accessed with the relayd_net_seq_idx_lock
101 * held.
102 */
103 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
104 static uint64_t relayd_net_seq_idx;
105
106 static int validate_ust_event_name(const char *);
107 static int cmd_enable_event_internal(struct ltt_session *session,
108 const struct lttng_domain *domain,
109 char *channel_name, struct lttng_event *event,
110 char *filter_expression,
111 struct lttng_filter_bytecode *filter,
112 struct lttng_event_exclusion *exclusion,
113 int wpipe);
114
115 /*
116 * Create a session path used by list_lttng_sessions for the case that the
117 * session consumer is on the network.
118 */
119 static int build_network_session_path(char *dst, size_t size,
120 struct ltt_session *session)
121 {
122 int ret, kdata_port, udata_port;
123 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
124 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
125
126 assert(session);
127 assert(dst);
128
129 memset(tmp_urls, 0, sizeof(tmp_urls));
130 memset(tmp_uurl, 0, sizeof(tmp_uurl));
131
132 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
133
134 if (session->kernel_session && session->kernel_session->consumer) {
135 kuri = &session->kernel_session->consumer->dst.net.control;
136 kdata_port = session->kernel_session->consumer->dst.net.data.port;
137 }
138
139 if (session->ust_session && session->ust_session->consumer) {
140 uuri = &session->ust_session->consumer->dst.net.control;
141 udata_port = session->ust_session->consumer->dst.net.data.port;
142 }
143
144 if (uuri == NULL && kuri == NULL) {
145 uri = &session->consumer->dst.net.control;
146 kdata_port = session->consumer->dst.net.data.port;
147 } else if (kuri && uuri) {
148 ret = uri_compare(kuri, uuri);
149 if (ret) {
150 /* Not Equal */
151 uri = kuri;
152 /* Build uuri URL string */
153 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
154 if (ret < 0) {
155 goto error;
156 }
157 } else {
158 uri = kuri;
159 }
160 } else if (kuri && uuri == NULL) {
161 uri = kuri;
162 } else if (uuri && kuri == NULL) {
163 uri = uuri;
164 }
165
166 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
167 if (ret < 0) {
168 goto error;
169 }
170
171 /*
172 * Do we have a UST url set. If yes, this means we have both kernel and UST
173 * to print.
174 */
175 if (*tmp_uurl != '\0') {
176 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
177 tmp_urls, kdata_port, tmp_uurl, udata_port);
178 } else {
179 int dport;
180 if (kuri || (!kuri && !uuri)) {
181 dport = kdata_port;
182 } else {
183 /* No kernel URI, use the UST port. */
184 dport = udata_port;
185 }
186 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
187 }
188
189 error:
190 return ret;
191 }
192
193 /*
194 * Get run-time attributes if the session has been started (discarded events,
195 * lost packets).
196 */
197 static int get_kernel_runtime_stats(struct ltt_session *session,
198 struct ltt_kernel_channel *kchan, uint64_t *discarded_events,
199 uint64_t *lost_packets)
200 {
201 int ret;
202
203 if (!session->has_been_started) {
204 ret = 0;
205 *discarded_events = 0;
206 *lost_packets = 0;
207 goto end;
208 }
209
210 ret = consumer_get_discarded_events(session->id, kchan->key,
211 session->kernel_session->consumer,
212 discarded_events);
213 if (ret < 0) {
214 goto end;
215 }
216
217 ret = consumer_get_lost_packets(session->id, kchan->key,
218 session->kernel_session->consumer,
219 lost_packets);
220 if (ret < 0) {
221 goto end;
222 }
223
224 end:
225 return ret;
226 }
227
228 /*
229 * Get run-time attributes if the session has been started (discarded events,
230 * lost packets).
231 */
232 static int get_ust_runtime_stats(struct ltt_session *session,
233 struct ltt_ust_channel *uchan, uint64_t *discarded_events,
234 uint64_t *lost_packets)
235 {
236 int ret;
237 struct ltt_ust_session *usess;
238
239 if (!discarded_events || !lost_packets) {
240 ret = -1;
241 goto end;
242 }
243
244 usess = session->ust_session;
245 assert(discarded_events);
246 assert(lost_packets);
247
248 if (!usess || !session->has_been_started) {
249 *discarded_events = 0;
250 *lost_packets = 0;
251 ret = 0;
252 goto end;
253 }
254
255 if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
256 ret = ust_app_uid_get_channel_runtime_stats(usess->id,
257 &usess->buffer_reg_uid_list,
258 usess->consumer, uchan->id,
259 uchan->attr.overwrite,
260 discarded_events,
261 lost_packets);
262 } else if (usess->buffer_type == LTTNG_BUFFER_PER_PID) {
263 ret = ust_app_pid_get_channel_runtime_stats(usess,
264 uchan, usess->consumer,
265 uchan->attr.overwrite,
266 discarded_events,
267 lost_packets);
268 if (ret < 0) {
269 goto end;
270 }
271 *discarded_events += uchan->per_pid_closed_app_discarded;
272 *lost_packets += uchan->per_pid_closed_app_lost;
273 } else {
274 ERR("Unsupported buffer type");
275 assert(0);
276 ret = -1;
277 goto end;
278 }
279
280 end:
281 return ret;
282 }
283
284 /*
285 * Fill lttng_channel array of all channels.
286 */
287 static ssize_t list_lttng_channels(enum lttng_domain_type domain,
288 struct ltt_session *session, struct lttng_channel *channels,
289 struct lttng_channel_extended *chan_exts)
290 {
291 int i = 0, ret = 0;
292 struct ltt_kernel_channel *kchan;
293
294 DBG("Listing channels for session %s", session->name);
295
296 switch (domain) {
297 case LTTNG_DOMAIN_KERNEL:
298 /* Kernel channels */
299 if (session->kernel_session != NULL) {
300 cds_list_for_each_entry(kchan,
301 &session->kernel_session->channel_list.head, list) {
302 uint64_t discarded_events, lost_packets;
303 struct lttng_channel_extended *extended;
304
305 extended = (struct lttng_channel_extended *)
306 kchan->channel->attr.extended.ptr;
307
308 ret = get_kernel_runtime_stats(session, kchan,
309 &discarded_events, &lost_packets);
310 if (ret < 0) {
311 goto end;
312 }
313 /* Copy lttng_channel struct to array */
314 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
315 channels[i].enabled = kchan->enabled;
316 chan_exts[i].discarded_events =
317 discarded_events;
318 chan_exts[i].lost_packets = lost_packets;
319 chan_exts[i].monitor_timer_interval =
320 extended->monitor_timer_interval;
321 chan_exts[i].blocking_timeout = 0;
322 i++;
323 }
324 }
325 break;
326 case LTTNG_DOMAIN_UST:
327 {
328 struct lttng_ht_iter iter;
329 struct ltt_ust_channel *uchan;
330
331 rcu_read_lock();
332 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
333 &iter.iter, uchan, node.node) {
334 uint64_t discarded_events = 0, lost_packets = 0;
335
336 if (lttng_strncpy(channels[i].name, uchan->name,
337 LTTNG_SYMBOL_NAME_LEN)) {
338 break;
339 }
340 channels[i].attr.overwrite = uchan->attr.overwrite;
341 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
342 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
343 channels[i].attr.switch_timer_interval =
344 uchan->attr.switch_timer_interval;
345 channels[i].attr.read_timer_interval =
346 uchan->attr.read_timer_interval;
347 channels[i].enabled = uchan->enabled;
348 channels[i].attr.tracefile_size = uchan->tracefile_size;
349 channels[i].attr.tracefile_count = uchan->tracefile_count;
350
351 /*
352 * Map enum lttng_ust_output to enum lttng_event_output.
353 */
354 switch (uchan->attr.output) {
355 case LTTNG_UST_MMAP:
356 channels[i].attr.output = LTTNG_EVENT_MMAP;
357 break;
358 default:
359 /*
360 * LTTNG_UST_MMAP is the only supported UST
361 * output mode.
362 */
363 assert(0);
364 break;
365 }
366
367 chan_exts[i].monitor_timer_interval =
368 uchan->monitor_timer_interval;
369 chan_exts[i].blocking_timeout =
370 uchan->attr.u.s.blocking_timeout;
371
372 ret = get_ust_runtime_stats(session, uchan,
373 &discarded_events, &lost_packets);
374 if (ret < 0) {
375 break;
376 }
377 chan_exts[i].discarded_events = discarded_events;
378 chan_exts[i].lost_packets = lost_packets;
379 i++;
380 }
381 rcu_read_unlock();
382 break;
383 }
384 default:
385 break;
386 }
387
388 end:
389 if (ret < 0) {
390 return -LTTNG_ERR_FATAL;
391 } else {
392 return LTTNG_OK;
393 }
394 }
395
396 static int increment_extended_len(const char *filter_expression,
397 struct lttng_event_exclusion *exclusion,
398 const struct lttng_userspace_probe_location *probe_location,
399 size_t *extended_len)
400 {
401 int ret = 0;
402
403 *extended_len += sizeof(struct lttcomm_event_extended_header);
404
405 if (filter_expression) {
406 *extended_len += strlen(filter_expression) + 1;
407 }
408
409 if (exclusion) {
410 *extended_len += exclusion->count * LTTNG_SYMBOL_NAME_LEN;
411 }
412
413 if (probe_location) {
414 ret = lttng_userspace_probe_location_serialize(probe_location,
415 NULL, NULL);
416 if (ret < 0) {
417 goto end;
418 }
419 *extended_len += ret;
420 }
421 ret = 0;
422 end:
423 return ret;
424 }
425
426 static int append_extended_info(const char *filter_expression,
427 struct lttng_event_exclusion *exclusion,
428 struct lttng_userspace_probe_location *probe_location,
429 void **extended_at)
430 {
431 int ret = 0;
432 size_t filter_len = 0;
433 size_t nb_exclusions = 0;
434 size_t userspace_probe_location_len = 0;
435 struct lttng_dynamic_buffer location_buffer;
436 struct lttcomm_event_extended_header extended_header;
437
438 if (filter_expression) {
439 filter_len = strlen(filter_expression) + 1;
440 }
441
442 if (exclusion) {
443 nb_exclusions = exclusion->count;
444 }
445
446 if (probe_location) {
447 lttng_dynamic_buffer_init(&location_buffer);
448 ret = lttng_userspace_probe_location_serialize(probe_location,
449 &location_buffer, NULL);
450 if (ret < 0) {
451 ret = -1;
452 goto end;
453 }
454 userspace_probe_location_len = location_buffer.size;
455 }
456
457 /* Set header fields */
458 extended_header.filter_len = filter_len;
459 extended_header.nb_exclusions = nb_exclusions;
460 extended_header.userspace_probe_location_len = userspace_probe_location_len;
461
462 /* Copy header */
463 memcpy(*extended_at, &extended_header, sizeof(extended_header));
464 *extended_at += sizeof(extended_header);
465
466 /* Copy filter string */
467 if (filter_expression) {
468 memcpy(*extended_at, filter_expression, filter_len);
469 *extended_at += filter_len;
470 }
471
472 /* Copy exclusion names */
473 if (exclusion) {
474 size_t len = nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
475
476 memcpy(*extended_at, &exclusion->names, len);
477 *extended_at += len;
478 }
479
480 if (probe_location) {
481 memcpy(*extended_at, location_buffer.data, location_buffer.size);
482 *extended_at += location_buffer.size;
483 lttng_dynamic_buffer_reset(&location_buffer);
484 }
485 ret = 0;
486 end:
487 return ret;
488 }
489
490 /*
491 * Create a list of agent domain events.
492 *
493 * Return number of events in list on success or else a negative value.
494 */
495 static int list_lttng_agent_events(struct agent *agt,
496 struct lttng_event **events, size_t *total_size)
497 {
498 int i = 0, ret = 0;
499 unsigned int nb_event = 0;
500 struct agent_event *event;
501 struct lttng_event *tmp_events = NULL;
502 struct lttng_ht_iter iter;
503 size_t extended_len = 0;
504 void *extended_at;
505
506 assert(agt);
507 assert(events);
508
509 DBG3("Listing agent events");
510
511 rcu_read_lock();
512 nb_event = lttng_ht_get_count(agt->events);
513 if (nb_event == 0) {
514 ret = nb_event;
515 *total_size = 0;
516 goto error;
517 }
518
519 /* Compute required extended infos size */
520 extended_len = nb_event * sizeof(struct lttcomm_event_extended_header);
521
522 /*
523 * This is only valid because the commands which add events are
524 * processed in the same thread as the listing.
525 */
526 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
527 ret = increment_extended_len(event->filter_expression, NULL, NULL,
528 &extended_len);
529 if (ret) {
530 DBG("Error computing the length of extended info message");
531 ret = -LTTNG_ERR_FATAL;
532 goto error;
533 }
534 }
535
536 *total_size = nb_event * sizeof(*tmp_events) + extended_len;
537 tmp_events = zmalloc(*total_size);
538 if (!tmp_events) {
539 PERROR("zmalloc agent events session");
540 ret = -LTTNG_ERR_FATAL;
541 goto error;
542 }
543
544 extended_at = ((uint8_t *) tmp_events) +
545 nb_event * sizeof(struct lttng_event);
546
547 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
548 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
549 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
550 tmp_events[i].enabled = event->enabled;
551 tmp_events[i].loglevel = event->loglevel_value;
552 tmp_events[i].loglevel_type = event->loglevel_type;
553 i++;
554
555 /* Append extended info */
556 ret = append_extended_info(event->filter_expression, NULL, NULL,
557 &extended_at);
558 if (ret) {
559 DBG("Error appending extended info message");
560 ret = -LTTNG_ERR_FATAL;
561 goto error;
562 }
563 }
564
565 *events = tmp_events;
566 ret = nb_event;
567 assert(nb_event == i);
568
569 end:
570 rcu_read_unlock();
571 return ret;
572 error:
573 free(tmp_events);
574 goto end;
575 }
576
577 /*
578 * Create a list of ust global domain events.
579 */
580 static int list_lttng_ust_global_events(char *channel_name,
581 struct ltt_ust_domain_global *ust_global,
582 struct lttng_event **events, size_t *total_size)
583 {
584 int i = 0, ret = 0;
585 unsigned int nb_event = 0;
586 struct lttng_ht_iter iter;
587 struct lttng_ht_node_str *node;
588 struct ltt_ust_channel *uchan;
589 struct ltt_ust_event *uevent;
590 struct lttng_event *tmp;
591 size_t extended_len = 0;
592 void *extended_at;
593
594 DBG("Listing UST global events for channel %s", channel_name);
595
596 rcu_read_lock();
597
598 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
599 node = lttng_ht_iter_get_node_str(&iter);
600 if (node == NULL) {
601 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
602 goto end;
603 }
604
605 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
606
607 nb_event = lttng_ht_get_count(uchan->events);
608 if (nb_event == 0) {
609 ret = nb_event;
610 *total_size = 0;
611 goto end;
612 }
613
614 DBG3("Listing UST global %d events", nb_event);
615
616 /* Compute required extended infos size */
617 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
618 if (uevent->internal) {
619 nb_event--;
620 continue;
621 }
622
623 ret = increment_extended_len(uevent->filter_expression,
624 uevent->exclusion, NULL, &extended_len);
625 if (ret) {
626 DBG("Error computing the length of extended info message");
627 ret = -LTTNG_ERR_FATAL;
628 goto end;
629 }
630 }
631 if (nb_event == 0) {
632 /* All events are internal, skip. */
633 ret = 0;
634 *total_size = 0;
635 goto end;
636 }
637
638 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
639 tmp = zmalloc(*total_size);
640 if (tmp == NULL) {
641 ret = -LTTNG_ERR_FATAL;
642 goto end;
643 }
644
645 extended_at = ((uint8_t *) tmp) + nb_event * sizeof(struct lttng_event);
646
647 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
648 if (uevent->internal) {
649 /* This event should remain hidden from clients */
650 continue;
651 }
652 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
653 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
654 tmp[i].enabled = uevent->enabled;
655
656 switch (uevent->attr.instrumentation) {
657 case LTTNG_UST_TRACEPOINT:
658 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
659 break;
660 case LTTNG_UST_PROBE:
661 tmp[i].type = LTTNG_EVENT_PROBE;
662 break;
663 case LTTNG_UST_FUNCTION:
664 tmp[i].type = LTTNG_EVENT_FUNCTION;
665 break;
666 }
667
668 tmp[i].loglevel = uevent->attr.loglevel;
669 switch (uevent->attr.loglevel_type) {
670 case LTTNG_UST_LOGLEVEL_ALL:
671 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
672 break;
673 case LTTNG_UST_LOGLEVEL_RANGE:
674 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
675 break;
676 case LTTNG_UST_LOGLEVEL_SINGLE:
677 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
678 break;
679 }
680 if (uevent->filter) {
681 tmp[i].filter = 1;
682 }
683 if (uevent->exclusion) {
684 tmp[i].exclusion = 1;
685 }
686 i++;
687
688 /* Append extended info */
689 ret = append_extended_info(uevent->filter_expression,
690 uevent->exclusion, NULL, &extended_at);
691 if (ret) {
692 DBG("Error appending extended info message");
693 ret = -LTTNG_ERR_FATAL;
694 goto end;
695 }
696 }
697
698 ret = nb_event;
699 *events = tmp;
700 end:
701 rcu_read_unlock();
702 return ret;
703 }
704
705 /*
706 * Fill lttng_event array of all kernel events in the channel.
707 */
708 static int list_lttng_kernel_events(char *channel_name,
709 struct ltt_kernel_session *kernel_session,
710 struct lttng_event **events, size_t *total_size)
711 {
712 int i = 0, ret;
713 unsigned int nb_event;
714 struct ltt_kernel_event *event;
715 struct ltt_kernel_channel *kchan;
716 size_t extended_len = 0;
717 void *extended_at;
718
719 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
720 if (kchan == NULL) {
721 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
722 goto error;
723 }
724
725 nb_event = kchan->event_count;
726
727 DBG("Listing events for channel %s", kchan->channel->name);
728
729 if (nb_event == 0) {
730 *total_size = 0;
731 *events = NULL;
732 goto end;
733 }
734
735 /* Compute required extended infos size */
736 cds_list_for_each_entry(event, &kchan->events_list.head, list) {
737 ret = increment_extended_len(event->filter_expression, NULL,
738 event->userspace_probe_location,
739 &extended_len);
740 if (ret) {
741 DBG("Error computing the length of extended info message");
742 ret = -LTTNG_ERR_FATAL;
743 goto error;
744 }
745 }
746
747 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
748 *events = zmalloc(*total_size);
749 if (*events == NULL) {
750 ret = -LTTNG_ERR_FATAL;
751 goto error;
752 }
753
754 extended_at = ((void *) *events) +
755 nb_event * sizeof(struct lttng_event);
756
757 /* Kernel channels */
758 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
759 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
760 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
761 (*events)[i].enabled = event->enabled;
762 (*events)[i].filter =
763 (unsigned char) !!event->filter_expression;
764
765 switch (event->event->instrumentation) {
766 case LTTNG_KERNEL_TRACEPOINT:
767 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
768 break;
769 case LTTNG_KERNEL_KRETPROBE:
770 (*events)[i].type = LTTNG_EVENT_FUNCTION;
771 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
772 sizeof(struct lttng_kernel_kprobe));
773 break;
774 case LTTNG_KERNEL_KPROBE:
775 (*events)[i].type = LTTNG_EVENT_PROBE;
776 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
777 sizeof(struct lttng_kernel_kprobe));
778 break;
779 case LTTNG_KERNEL_UPROBE:
780 (*events)[i].type = LTTNG_EVENT_USERSPACE_PROBE;
781 break;
782 case LTTNG_KERNEL_FUNCTION:
783 (*events)[i].type = LTTNG_EVENT_FUNCTION;
784 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
785 sizeof(struct lttng_kernel_function));
786 break;
787 case LTTNG_KERNEL_NOOP:
788 (*events)[i].type = LTTNG_EVENT_NOOP;
789 break;
790 case LTTNG_KERNEL_SYSCALL:
791 (*events)[i].type = LTTNG_EVENT_SYSCALL;
792 break;
793 case LTTNG_KERNEL_ALL:
794 /* fall-through. */
795 default:
796 assert(0);
797 break;
798 }
799 i++;
800
801 /* Append extended info */
802 ret = append_extended_info(event->filter_expression, NULL,
803 event->userspace_probe_location, &extended_at);
804 if (ret) {
805 DBG("Error appending extended info message");
806 ret = -LTTNG_ERR_FATAL;
807 goto error;
808 }
809 }
810
811 end:
812 return nb_event;
813
814 error:
815 return ret;
816 }
817
818 /*
819 * Add URI so the consumer output object. Set the correct path depending on the
820 * domain adding the default trace directory.
821 */
822 static enum lttng_error_code add_uri_to_consumer(
823 const struct ltt_session *session,
824 struct consumer_output *consumer,
825 struct lttng_uri *uri, enum lttng_domain_type domain)
826 {
827 int ret;
828 enum lttng_error_code ret_code = LTTNG_OK;
829
830 assert(uri);
831
832 if (consumer == NULL) {
833 DBG("No consumer detected. Don't add URI. Stopping.");
834 ret_code = LTTNG_ERR_NO_CONSUMER;
835 goto error;
836 }
837
838 switch (domain) {
839 case LTTNG_DOMAIN_KERNEL:
840 ret = lttng_strncpy(consumer->domain_subdir,
841 DEFAULT_KERNEL_TRACE_DIR,
842 sizeof(consumer->domain_subdir));
843 break;
844 case LTTNG_DOMAIN_UST:
845 ret = lttng_strncpy(consumer->domain_subdir,
846 DEFAULT_UST_TRACE_DIR,
847 sizeof(consumer->domain_subdir));
848 break;
849 default:
850 /*
851 * This case is possible is we try to add the URI to the global
852 * tracing session consumer object which in this case there is
853 * no subdir.
854 */
855 memset(consumer->domain_subdir, 0,
856 sizeof(consumer->domain_subdir));
857 ret = 0;
858 }
859 if (ret) {
860 ERR("Failed to initialize consumer output domain subdirectory");
861 ret_code = LTTNG_ERR_FATAL;
862 goto error;
863 }
864
865 switch (uri->dtype) {
866 case LTTNG_DST_IPV4:
867 case LTTNG_DST_IPV6:
868 DBG2("Setting network URI to consumer");
869
870 if (consumer->type == CONSUMER_DST_NET) {
871 if ((uri->stype == LTTNG_STREAM_CONTROL &&
872 consumer->dst.net.control_isset) ||
873 (uri->stype == LTTNG_STREAM_DATA &&
874 consumer->dst.net.data_isset)) {
875 ret_code = LTTNG_ERR_URL_EXIST;
876 goto error;
877 }
878 } else {
879 memset(&consumer->dst, 0, sizeof(consumer->dst));
880 }
881
882 /* Set URI into consumer output object */
883 ret = consumer_set_network_uri(session, consumer, uri);
884 if (ret < 0) {
885 ret_code = -ret;
886 goto error;
887 } else if (ret == 1) {
888 /*
889 * URI was the same in the consumer so we do not append the subdir
890 * again so to not duplicate output dir.
891 */
892 ret_code = LTTNG_OK;
893 goto error;
894 }
895 break;
896 case LTTNG_DST_PATH:
897 if (*uri->dst.path != '/' || strstr(uri->dst.path, "../")) {
898 ret_code = LTTNG_ERR_INVALID;
899 goto error;
900 }
901 DBG2("Setting trace directory path from URI to %s",
902 uri->dst.path);
903 memset(&consumer->dst, 0, sizeof(consumer->dst));
904
905 ret = lttng_strncpy(consumer->dst.session_root_path,
906 uri->dst.path,
907 sizeof(consumer->dst.session_root_path));
908 if (ret) {
909 ret_code = LTTNG_ERR_FATAL;
910 goto error;
911 }
912 consumer->type = CONSUMER_DST_LOCAL;
913 break;
914 }
915
916 ret_code = LTTNG_OK;
917 error:
918 return ret_code;
919 }
920
921 /*
922 * Init tracing by creating trace directory and sending fds kernel consumer.
923 */
924 static int init_kernel_tracing(struct ltt_kernel_session *session)
925 {
926 int ret = 0;
927 struct lttng_ht_iter iter;
928 struct consumer_socket *socket;
929
930 assert(session);
931
932 rcu_read_lock();
933
934 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
935 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
936 socket, node.node) {
937 pthread_mutex_lock(socket->lock);
938 ret = kernel_consumer_send_session(socket, session);
939 pthread_mutex_unlock(socket->lock);
940 if (ret < 0) {
941 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
942 goto error;
943 }
944 }
945 }
946
947 error:
948 rcu_read_unlock();
949 return ret;
950 }
951
952 /*
953 * Create a socket to the relayd using the URI.
954 *
955 * On success, the relayd_sock pointer is set to the created socket.
956 * Else, it remains untouched and an LTTng error code is returned.
957 */
958 static enum lttng_error_code create_connect_relayd(struct lttng_uri *uri,
959 struct lttcomm_relayd_sock **relayd_sock,
960 struct consumer_output *consumer)
961 {
962 int ret;
963 enum lttng_error_code status = LTTNG_OK;
964 struct lttcomm_relayd_sock *rsock;
965
966 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
967 RELAYD_VERSION_COMM_MINOR);
968 if (!rsock) {
969 status = LTTNG_ERR_FATAL;
970 goto error;
971 }
972
973 /*
974 * Connect to relayd so we can proceed with a session creation. This call
975 * can possibly block for an arbitrary amount of time to set the health
976 * state to be in poll execution.
977 */
978 health_poll_entry();
979 ret = relayd_connect(rsock);
980 health_poll_exit();
981 if (ret < 0) {
982 ERR("Unable to reach lttng-relayd");
983 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
984 goto free_sock;
985 }
986
987 /* Create socket for control stream. */
988 if (uri->stype == LTTNG_STREAM_CONTROL) {
989 uint64_t result_flags;
990
991 DBG3("Creating relayd stream socket from URI");
992
993 /* Check relayd version */
994 ret = relayd_version_check(rsock);
995 if (ret == LTTNG_ERR_RELAYD_VERSION_FAIL) {
996 status = LTTNG_ERR_RELAYD_VERSION_FAIL;
997 goto close_sock;
998 } else if (ret < 0) {
999 ERR("Unable to reach lttng-relayd");
1000 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
1001 goto close_sock;
1002 }
1003 consumer->relay_major_version = rsock->major;
1004 consumer->relay_minor_version = rsock->minor;
1005 ret = relayd_get_configuration(rsock, 0,
1006 &result_flags);
1007 if (ret < 0) {
1008 ERR("Unable to get relayd configuration");
1009 status = LTTNG_ERR_RELAYD_CONNECT_FAIL;
1010 goto close_sock;
1011 }
1012 if (result_flags & LTTCOMM_RELAYD_CONFIGURATION_FLAG_CLEAR_ALLOWED) {
1013 consumer->relay_allows_clear = true;
1014 }
1015 } else if (uri->stype == LTTNG_STREAM_DATA) {
1016 DBG3("Creating relayd data socket from URI");
1017 } else {
1018 /* Command is not valid */
1019 ERR("Relayd invalid stream type: %d", uri->stype);
1020 status = LTTNG_ERR_INVALID;
1021 goto close_sock;
1022 }
1023
1024 *relayd_sock = rsock;
1025
1026 return status;
1027
1028 close_sock:
1029 /* The returned value is not useful since we are on an error path. */
1030 (void) relayd_close(rsock);
1031 free_sock:
1032 free(rsock);
1033 error:
1034 return status;
1035 }
1036
1037 /*
1038 * Connect to the relayd using URI and send the socket to the right consumer.
1039 *
1040 * The consumer socket lock must be held by the caller.
1041 *
1042 * Returns LTTNG_OK on success or an LTTng error code on failure.
1043 */
1044 static enum lttng_error_code send_consumer_relayd_socket(
1045 unsigned int session_id,
1046 struct lttng_uri *relayd_uri,
1047 struct consumer_output *consumer,
1048 struct consumer_socket *consumer_sock,
1049 const char *session_name, const char *hostname,
1050 const char *base_path, int session_live_timer,
1051 const uint64_t *current_chunk_id,
1052 time_t session_creation_time,
1053 bool session_name_contains_creation_time)
1054 {
1055 int ret;
1056 struct lttcomm_relayd_sock *rsock = NULL;
1057 enum lttng_error_code status;
1058
1059 /* Connect to relayd and make version check if uri is the control. */
1060 status = create_connect_relayd(relayd_uri, &rsock, consumer);
1061 if (status != LTTNG_OK) {
1062 goto relayd_comm_error;
1063 }
1064 assert(rsock);
1065
1066 /* Set the network sequence index if not set. */
1067 if (consumer->net_seq_index == (uint64_t) -1ULL) {
1068 pthread_mutex_lock(&relayd_net_seq_idx_lock);
1069 /*
1070 * Increment net_seq_idx because we are about to transfer the
1071 * new relayd socket to the consumer.
1072 * Assign unique key so the consumer can match streams.
1073 */
1074 consumer->net_seq_index = ++relayd_net_seq_idx;
1075 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
1076 }
1077
1078 /* Send relayd socket to consumer. */
1079 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
1080 relayd_uri->stype, session_id,
1081 session_name, hostname, base_path,
1082 session_live_timer, current_chunk_id,
1083 session_creation_time, session_name_contains_creation_time);
1084 if (ret < 0) {
1085 status = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
1086 goto close_sock;
1087 }
1088
1089 /* Flag that the corresponding socket was sent. */
1090 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
1091 consumer_sock->control_sock_sent = 1;
1092 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
1093 consumer_sock->data_sock_sent = 1;
1094 }
1095
1096 /*
1097 * Close socket which was dup on the consumer side. The session daemon does
1098 * NOT keep track of the relayd socket(s) once transfer to the consumer.
1099 */
1100
1101 close_sock:
1102 if (status != LTTNG_OK) {
1103 /*
1104 * The consumer output for this session should not be used anymore
1105 * since the relayd connection failed thus making any tracing or/and
1106 * streaming not usable.
1107 */
1108 consumer->enabled = 0;
1109 }
1110 (void) relayd_close(rsock);
1111 free(rsock);
1112
1113 relayd_comm_error:
1114 return status;
1115 }
1116
1117 /*
1118 * Send both relayd sockets to a specific consumer and domain. This is a
1119 * helper function to facilitate sending the information to the consumer for a
1120 * session.
1121 *
1122 * The consumer socket lock must be held by the caller.
1123 *
1124 * Returns LTTNG_OK, or an LTTng error code on failure.
1125 */
1126 static enum lttng_error_code send_consumer_relayd_sockets(
1127 enum lttng_domain_type domain,
1128 unsigned int session_id, struct consumer_output *consumer,
1129 struct consumer_socket *sock, const char *session_name,
1130 const char *hostname, const char *base_path, int session_live_timer,
1131 const uint64_t *current_chunk_id, time_t session_creation_time,
1132 bool session_name_contains_creation_time)
1133 {
1134 enum lttng_error_code status = LTTNG_OK;
1135
1136 assert(consumer);
1137 assert(sock);
1138
1139 /* Sending control relayd socket. */
1140 if (!sock->control_sock_sent) {
1141 status = send_consumer_relayd_socket(session_id,
1142 &consumer->dst.net.control, consumer, sock,
1143 session_name, hostname, base_path, session_live_timer,
1144 current_chunk_id, session_creation_time,
1145 session_name_contains_creation_time);
1146 if (status != LTTNG_OK) {
1147 goto error;
1148 }
1149 }
1150
1151 /* Sending data relayd socket. */
1152 if (!sock->data_sock_sent) {
1153 status = send_consumer_relayd_socket(session_id,
1154 &consumer->dst.net.data, consumer, sock,
1155 session_name, hostname, base_path, session_live_timer,
1156 current_chunk_id, session_creation_time,
1157 session_name_contains_creation_time);
1158 if (status != LTTNG_OK) {
1159 goto error;
1160 }
1161 }
1162
1163 error:
1164 return status;
1165 }
1166
1167 /*
1168 * Setup relayd connections for a tracing session. First creates the socket to
1169 * the relayd and send them to the right domain consumer. Consumer type MUST be
1170 * network.
1171 */
1172 int cmd_setup_relayd(struct ltt_session *session)
1173 {
1174 int ret = LTTNG_OK;
1175 struct ltt_ust_session *usess;
1176 struct ltt_kernel_session *ksess;
1177 struct consumer_socket *socket;
1178 struct lttng_ht_iter iter;
1179 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
1180
1181 assert(session);
1182
1183 usess = session->ust_session;
1184 ksess = session->kernel_session;
1185
1186 DBG("Setting relayd for session %s", session->name);
1187
1188 rcu_read_lock();
1189 if (session->current_trace_chunk) {
1190 enum lttng_trace_chunk_status status = lttng_trace_chunk_get_id(
1191 session->current_trace_chunk, &current_chunk_id.value);
1192
1193 if (status == LTTNG_TRACE_CHUNK_STATUS_OK) {
1194 current_chunk_id.is_set = true;
1195 } else {
1196 ERR("Failed to get current trace chunk id");
1197 ret = LTTNG_ERR_UNK;
1198 goto error;
1199 }
1200 }
1201
1202 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1203 && usess->consumer->enabled) {
1204 /* For each consumer socket, send relayd sockets */
1205 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1206 socket, node.node) {
1207 pthread_mutex_lock(socket->lock);
1208 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1209 usess->consumer, socket,
1210 session->name, session->hostname,
1211 session->base_path,
1212 session->live_timer,
1213 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1214 session->creation_time,
1215 session->name_contains_creation_time);
1216 pthread_mutex_unlock(socket->lock);
1217 if (ret != LTTNG_OK) {
1218 goto error;
1219 }
1220 /* Session is now ready for network streaming. */
1221 session->net_handle = 1;
1222 }
1223 session->consumer->relay_major_version =
1224 usess->consumer->relay_major_version;
1225 session->consumer->relay_minor_version =
1226 usess->consumer->relay_minor_version;
1227 session->consumer->relay_allows_clear =
1228 usess->consumer->relay_allows_clear;
1229 }
1230
1231 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1232 && ksess->consumer->enabled) {
1233 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1234 socket, node.node) {
1235 pthread_mutex_lock(socket->lock);
1236 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1237 ksess->consumer, socket,
1238 session->name, session->hostname,
1239 session->base_path,
1240 session->live_timer,
1241 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
1242 session->creation_time,
1243 session->name_contains_creation_time);
1244 pthread_mutex_unlock(socket->lock);
1245 if (ret != LTTNG_OK) {
1246 goto error;
1247 }
1248 /* Session is now ready for network streaming. */
1249 session->net_handle = 1;
1250 }
1251 session->consumer->relay_major_version =
1252 ksess->consumer->relay_major_version;
1253 session->consumer->relay_minor_version =
1254 ksess->consumer->relay_minor_version;
1255 session->consumer->relay_allows_clear =
1256 ksess->consumer->relay_allows_clear;
1257 }
1258
1259 error:
1260 rcu_read_unlock();
1261 return ret;
1262 }
1263
1264 /*
1265 * Start a kernel session by opening all necessary streams.
1266 */
1267 int start_kernel_session(struct ltt_kernel_session *ksess)
1268 {
1269 int ret;
1270 struct ltt_kernel_channel *kchan;
1271
1272 /* Open kernel metadata */
1273 if (ksess->metadata == NULL && ksess->output_traces) {
1274 ret = kernel_open_metadata(ksess);
1275 if (ret < 0) {
1276 ret = LTTNG_ERR_KERN_META_FAIL;
1277 goto error;
1278 }
1279 }
1280
1281 /* Open kernel metadata stream */
1282 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1283 ret = kernel_open_metadata_stream(ksess);
1284 if (ret < 0) {
1285 ERR("Kernel create metadata stream failed");
1286 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1287 goto error;
1288 }
1289 }
1290
1291 /* For each channel */
1292 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1293 if (kchan->stream_count == 0) {
1294 ret = kernel_open_channel_stream(kchan);
1295 if (ret < 0) {
1296 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1297 goto error;
1298 }
1299 /* Update the stream global counter */
1300 ksess->stream_count_global += ret;
1301 }
1302 }
1303
1304 /* Setup kernel consumer socket and send fds to it */
1305 ret = init_kernel_tracing(ksess);
1306 if (ret != 0) {
1307 ret = LTTNG_ERR_KERN_START_FAIL;
1308 goto error;
1309 }
1310
1311 /* This start the kernel tracing */
1312 ret = kernel_start_session(ksess);
1313 if (ret < 0) {
1314 ret = LTTNG_ERR_KERN_START_FAIL;
1315 goto error;
1316 }
1317
1318 /* Quiescent wait after starting trace */
1319 kernel_wait_quiescent();
1320
1321 ksess->active = 1;
1322
1323 ret = LTTNG_OK;
1324
1325 error:
1326 return ret;
1327 }
1328
1329 int stop_kernel_session(struct ltt_kernel_session *ksess)
1330 {
1331 struct ltt_kernel_channel *kchan;
1332 bool error_occurred = false;
1333 int ret;
1334
1335 if (!ksess || !ksess->active) {
1336 return LTTNG_OK;
1337 }
1338 DBG("Stopping kernel tracing");
1339
1340 ret = kernel_stop_session(ksess);
1341 if (ret < 0) {
1342 ret = LTTNG_ERR_KERN_STOP_FAIL;
1343 goto error;
1344 }
1345
1346 kernel_wait_quiescent();
1347
1348 /* Flush metadata after stopping (if exists) */
1349 if (ksess->metadata_stream_fd >= 0) {
1350 ret = kernel_metadata_flush_buffer(ksess->metadata_stream_fd);
1351 if (ret < 0) {
1352 ERR("Kernel metadata flush failed");
1353 error_occurred = true;
1354 }
1355 }
1356
1357 /* Flush all buffers after stopping */
1358 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1359 ret = kernel_flush_buffer(kchan);
1360 if (ret < 0) {
1361 ERR("Kernel flush buffer error");
1362 error_occurred = true;
1363 }
1364 }
1365
1366 ksess->active = 0;
1367 if (error_occurred) {
1368 ret = LTTNG_ERR_UNK;
1369 } else {
1370 ret = LTTNG_OK;
1371 }
1372 error:
1373 return ret;
1374 }
1375
1376 /*
1377 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1378 */
1379 int cmd_disable_channel(struct ltt_session *session,
1380 enum lttng_domain_type domain, char *channel_name)
1381 {
1382 int ret;
1383 struct ltt_ust_session *usess;
1384
1385 usess = session->ust_session;
1386
1387 rcu_read_lock();
1388
1389 switch (domain) {
1390 case LTTNG_DOMAIN_KERNEL:
1391 {
1392 ret = channel_kernel_disable(session->kernel_session,
1393 channel_name);
1394 if (ret != LTTNG_OK) {
1395 goto error;
1396 }
1397
1398 kernel_wait_quiescent();
1399 break;
1400 }
1401 case LTTNG_DOMAIN_UST:
1402 {
1403 struct ltt_ust_channel *uchan;
1404 struct lttng_ht *chan_ht;
1405
1406 chan_ht = usess->domain_global.channels;
1407
1408 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1409 if (uchan == NULL) {
1410 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1411 goto error;
1412 }
1413
1414 ret = channel_ust_disable(usess, uchan);
1415 if (ret != LTTNG_OK) {
1416 goto error;
1417 }
1418 break;
1419 }
1420 default:
1421 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1422 goto error;
1423 }
1424
1425 ret = LTTNG_OK;
1426
1427 error:
1428 rcu_read_unlock();
1429 return ret;
1430 }
1431
1432 /*
1433 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1434 *
1435 * The wpipe arguments is used as a notifier for the kernel thread.
1436 */
1437 int cmd_enable_channel(struct ltt_session *session,
1438 const struct lttng_domain *domain, const struct lttng_channel *_attr, int wpipe)
1439 {
1440 int ret;
1441 struct ltt_ust_session *usess = session->ust_session;
1442 struct lttng_ht *chan_ht;
1443 size_t len;
1444 struct lttng_channel attr;
1445
1446 assert(session);
1447 assert(_attr);
1448 assert(domain);
1449
1450 attr = *_attr;
1451 len = lttng_strnlen(attr.name, sizeof(attr.name));
1452
1453 /* Validate channel name */
1454 if (attr.name[0] == '.' ||
1455 memchr(attr.name, '/', len) != NULL) {
1456 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1457 goto end;
1458 }
1459
1460 DBG("Enabling channel %s for session %s", attr.name, session->name);
1461
1462 rcu_read_lock();
1463
1464 /*
1465 * If the session is a live session, remove the switch timer, the
1466 * live timer does the same thing but sends also synchronisation
1467 * beacons for inactive streams.
1468 */
1469 if (session->live_timer > 0) {
1470 attr.attr.live_timer_interval = session->live_timer;
1471 attr.attr.switch_timer_interval = 0;
1472 }
1473
1474 /* Check for feature support */
1475 switch (domain->type) {
1476 case LTTNG_DOMAIN_KERNEL:
1477 {
1478 if (kernel_supports_ring_buffer_snapshot_sample_positions() != 1) {
1479 /* Sampling position of buffer is not supported */
1480 WARN("Kernel tracer does not support buffer monitoring. "
1481 "Setting the monitor interval timer to 0 "
1482 "(disabled) for channel '%s' of session '%s'",
1483 attr.name, session->name);
1484 lttng_channel_set_monitor_timer_interval(&attr, 0);
1485 }
1486 break;
1487 }
1488 case LTTNG_DOMAIN_UST:
1489 break;
1490 case LTTNG_DOMAIN_JUL:
1491 case LTTNG_DOMAIN_LOG4J:
1492 case LTTNG_DOMAIN_PYTHON:
1493 if (!agent_tracing_is_enabled()) {
1494 DBG("Attempted to enable a channel in an agent domain but the agent thread is not running");
1495 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
1496 goto error;
1497 }
1498 break;
1499 default:
1500 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1501 goto error;
1502 }
1503
1504 switch (domain->type) {
1505 case LTTNG_DOMAIN_KERNEL:
1506 {
1507 struct ltt_kernel_channel *kchan;
1508
1509 kchan = trace_kernel_get_channel_by_name(attr.name,
1510 session->kernel_session);
1511 if (kchan == NULL) {
1512 /*
1513 * Don't try to create a channel if the session has been started at
1514 * some point in time before. The tracer does not allow it.
1515 */
1516 if (session->has_been_started) {
1517 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1518 goto error;
1519 }
1520
1521 if (session->snapshot.nb_output > 0 ||
1522 session->snapshot_mode) {
1523 /* Enforce mmap output for snapshot sessions. */
1524 attr.attr.output = LTTNG_EVENT_MMAP;
1525 }
1526 ret = channel_kernel_create(session->kernel_session, &attr, wpipe);
1527 if (attr.name[0] != '\0') {
1528 session->kernel_session->has_non_default_channel = 1;
1529 }
1530 } else {
1531 ret = channel_kernel_enable(session->kernel_session, kchan);
1532 }
1533
1534 if (ret != LTTNG_OK) {
1535 goto error;
1536 }
1537
1538 kernel_wait_quiescent();
1539 break;
1540 }
1541 case LTTNG_DOMAIN_UST:
1542 case LTTNG_DOMAIN_JUL:
1543 case LTTNG_DOMAIN_LOG4J:
1544 case LTTNG_DOMAIN_PYTHON:
1545 {
1546 struct ltt_ust_channel *uchan;
1547
1548 /*
1549 * FIXME
1550 *
1551 * Current agent implementation limitations force us to allow
1552 * only one channel at once in "agent" subdomains. Each
1553 * subdomain has a default channel name which must be strictly
1554 * adhered to.
1555 */
1556 if (domain->type == LTTNG_DOMAIN_JUL) {
1557 if (strncmp(attr.name, DEFAULT_JUL_CHANNEL_NAME,
1558 LTTNG_SYMBOL_NAME_LEN)) {
1559 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1560 goto error;
1561 }
1562 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1563 if (strncmp(attr.name, DEFAULT_LOG4J_CHANNEL_NAME,
1564 LTTNG_SYMBOL_NAME_LEN)) {
1565 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1566 goto error;
1567 }
1568 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1569 if (strncmp(attr.name, DEFAULT_PYTHON_CHANNEL_NAME,
1570 LTTNG_SYMBOL_NAME_LEN)) {
1571 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1572 goto error;
1573 }
1574 }
1575
1576 chan_ht = usess->domain_global.channels;
1577
1578 uchan = trace_ust_find_channel_by_name(chan_ht, attr.name);
1579 if (uchan == NULL) {
1580 /*
1581 * Don't try to create a channel if the session has been started at
1582 * some point in time before. The tracer does not allow it.
1583 */
1584 if (session->has_been_started) {
1585 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1586 goto error;
1587 }
1588
1589 ret = channel_ust_create(usess, &attr, domain->buf_type);
1590 if (attr.name[0] != '\0') {
1591 usess->has_non_default_channel = 1;
1592 }
1593 } else {
1594 ret = channel_ust_enable(usess, uchan);
1595 }
1596 break;
1597 }
1598 default:
1599 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1600 goto error;
1601 }
1602
1603 if (ret == LTTNG_OK && attr.attr.output != LTTNG_EVENT_MMAP) {
1604 session->has_non_mmap_channel = true;
1605 }
1606 error:
1607 rcu_read_unlock();
1608 end:
1609 return ret;
1610 }
1611
1612 enum lttng_error_code cmd_process_attr_tracker_get_tracking_policy(
1613 struct ltt_session *session,
1614 enum lttng_domain_type domain,
1615 enum lttng_process_attr process_attr,
1616 enum lttng_tracking_policy *policy)
1617 {
1618 enum lttng_error_code ret_code = LTTNG_OK;
1619 const struct process_attr_tracker *tracker;
1620
1621 switch (domain) {
1622 case LTTNG_DOMAIN_KERNEL:
1623 if (!session->kernel_session) {
1624 ret_code = LTTNG_ERR_INVALID;
1625 goto end;
1626 }
1627 tracker = kernel_get_process_attr_tracker(
1628 session->kernel_session, process_attr);
1629 break;
1630 case LTTNG_DOMAIN_UST:
1631 if (!session->ust_session) {
1632 ret_code = LTTNG_ERR_INVALID;
1633 goto end;
1634 }
1635 tracker = trace_ust_get_process_attr_tracker(
1636 session->ust_session, process_attr);
1637 break;
1638 default:
1639 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1640 goto end;
1641 }
1642 if (tracker) {
1643 *policy = process_attr_tracker_get_tracking_policy(tracker);
1644 } else {
1645 ret_code = LTTNG_ERR_INVALID;
1646 }
1647 end:
1648 return ret_code;
1649 }
1650
1651 enum lttng_error_code cmd_process_attr_tracker_set_tracking_policy(
1652 struct ltt_session *session,
1653 enum lttng_domain_type domain,
1654 enum lttng_process_attr process_attr,
1655 enum lttng_tracking_policy policy)
1656 {
1657 enum lttng_error_code ret_code = LTTNG_OK;
1658
1659 switch (policy) {
1660 case LTTNG_TRACKING_POLICY_INCLUDE_SET:
1661 case LTTNG_TRACKING_POLICY_EXCLUDE_ALL:
1662 case LTTNG_TRACKING_POLICY_INCLUDE_ALL:
1663 break;
1664 default:
1665 ret_code = LTTNG_ERR_INVALID;
1666 goto end;
1667 }
1668
1669 switch (domain) {
1670 case LTTNG_DOMAIN_KERNEL:
1671 if (!session->kernel_session) {
1672 ret_code = LTTNG_ERR_INVALID;
1673 goto end;
1674 }
1675 ret_code = kernel_process_attr_tracker_set_tracking_policy(
1676 session->kernel_session, process_attr, policy);
1677 break;
1678 case LTTNG_DOMAIN_UST:
1679 if (!session->ust_session) {
1680 ret_code = LTTNG_ERR_INVALID;
1681 goto end;
1682 }
1683 ret_code = trace_ust_process_attr_tracker_set_tracking_policy(
1684 session->ust_session, process_attr, policy);
1685 break;
1686 default:
1687 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1688 break;
1689 }
1690 end:
1691 return ret_code;
1692 }
1693
1694 enum lttng_error_code cmd_process_attr_tracker_inclusion_set_add_value(
1695 struct ltt_session *session,
1696 enum lttng_domain_type domain,
1697 enum lttng_process_attr process_attr,
1698 const struct process_attr_value *value)
1699 {
1700 enum lttng_error_code ret_code = LTTNG_OK;
1701
1702 switch (domain) {
1703 case LTTNG_DOMAIN_KERNEL:
1704 if (!session->kernel_session) {
1705 ret_code = LTTNG_ERR_INVALID;
1706 goto end;
1707 }
1708 ret_code = kernel_process_attr_tracker_inclusion_set_add_value(
1709 session->kernel_session, process_attr, value);
1710 break;
1711 case LTTNG_DOMAIN_UST:
1712 if (!session->ust_session) {
1713 ret_code = LTTNG_ERR_INVALID;
1714 goto end;
1715 }
1716 ret_code = trace_ust_process_attr_tracker_inclusion_set_add_value(
1717 session->ust_session, process_attr, value);
1718 break;
1719 default:
1720 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1721 break;
1722 }
1723 end:
1724 return ret_code;
1725 }
1726
1727 enum lttng_error_code cmd_process_attr_tracker_inclusion_set_remove_value(
1728 struct ltt_session *session,
1729 enum lttng_domain_type domain,
1730 enum lttng_process_attr process_attr,
1731 const struct process_attr_value *value)
1732 {
1733 enum lttng_error_code ret_code = LTTNG_OK;
1734
1735 switch (domain) {
1736 case LTTNG_DOMAIN_KERNEL:
1737 if (!session->kernel_session) {
1738 ret_code = LTTNG_ERR_INVALID;
1739 goto end;
1740 }
1741 ret_code = kernel_process_attr_tracker_inclusion_set_remove_value(
1742 session->kernel_session, process_attr, value);
1743 break;
1744 case LTTNG_DOMAIN_UST:
1745 if (!session->ust_session) {
1746 ret_code = LTTNG_ERR_INVALID;
1747 goto end;
1748 }
1749 ret_code = trace_ust_process_attr_tracker_inclusion_set_remove_value(
1750 session->ust_session, process_attr, value);
1751 break;
1752 default:
1753 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1754 break;
1755 }
1756 end:
1757 return ret_code;
1758 }
1759
1760 enum lttng_error_code cmd_process_attr_tracker_get_inclusion_set(
1761 struct ltt_session *session,
1762 enum lttng_domain_type domain,
1763 enum lttng_process_attr process_attr,
1764 struct lttng_process_attr_values **values)
1765 {
1766 enum lttng_error_code ret_code = LTTNG_OK;
1767 const struct process_attr_tracker *tracker;
1768 enum process_attr_tracker_status status;
1769
1770 switch (domain) {
1771 case LTTNG_DOMAIN_KERNEL:
1772 if (!session->kernel_session) {
1773 ret_code = LTTNG_ERR_INVALID;
1774 goto end;
1775 }
1776 tracker = kernel_get_process_attr_tracker(
1777 session->kernel_session, process_attr);
1778 break;
1779 case LTTNG_DOMAIN_UST:
1780 if (!session->ust_session) {
1781 ret_code = LTTNG_ERR_INVALID;
1782 goto end;
1783 }
1784 tracker = trace_ust_get_process_attr_tracker(
1785 session->ust_session, process_attr);
1786 break;
1787 default:
1788 ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
1789 goto end;
1790 }
1791
1792 if (!tracker) {
1793 ret_code = LTTNG_ERR_INVALID;
1794 goto end;
1795 }
1796
1797 status = process_attr_tracker_get_inclusion_set(tracker, values);
1798 switch (status) {
1799 case PROCESS_ATTR_TRACKER_STATUS_OK:
1800 ret_code = LTTNG_OK;
1801 break;
1802 case PROCESS_ATTR_TRACKER_STATUS_INVALID_TRACKING_POLICY:
1803 ret_code = LTTNG_ERR_PROCESS_ATTR_TRACKER_INVALID_TRACKING_POLICY;
1804 break;
1805 case PROCESS_ATTR_TRACKER_STATUS_ERROR:
1806 ret_code = LTTNG_ERR_NOMEM;
1807 break;
1808 default:
1809 ret_code = LTTNG_ERR_UNK;
1810 break;
1811 }
1812
1813 end:
1814 return ret_code;
1815 }
1816
1817 /*
1818 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1819 */
1820 int cmd_disable_event(struct ltt_session *session,
1821 enum lttng_domain_type domain, const char *channel_name,
1822 const struct lttng_event *event)
1823 {
1824 int ret;
1825 const char *event_name;
1826
1827 DBG("Disable event command for event \'%s\'", event->name);
1828
1829 event_name = event->name;
1830
1831 /* Error out on unhandled search criteria */
1832 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1833 || event->pid || event->filter || event->exclusion) {
1834 ret = LTTNG_ERR_UNK;
1835 goto error;
1836 }
1837
1838 rcu_read_lock();
1839
1840 switch (domain) {
1841 case LTTNG_DOMAIN_KERNEL:
1842 {
1843 struct ltt_kernel_channel *kchan;
1844 struct ltt_kernel_session *ksess;
1845
1846 ksess = session->kernel_session;
1847
1848 /*
1849 * If a non-default channel has been created in the
1850 * session, explicitely require that -c chan_name needs
1851 * to be provided.
1852 */
1853 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1854 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1855 goto error_unlock;
1856 }
1857
1858 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1859 if (kchan == NULL) {
1860 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1861 goto error_unlock;
1862 }
1863
1864 switch (event->type) {
1865 case LTTNG_EVENT_ALL:
1866 case LTTNG_EVENT_TRACEPOINT:
1867 case LTTNG_EVENT_SYSCALL:
1868 case LTTNG_EVENT_PROBE:
1869 case LTTNG_EVENT_FUNCTION:
1870 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1871 if (event_name[0] == '\0') {
1872 ret = event_kernel_disable_event(kchan,
1873 NULL, event->type);
1874 } else {
1875 ret = event_kernel_disable_event(kchan,
1876 event_name, event->type);
1877 }
1878 if (ret != LTTNG_OK) {
1879 goto error_unlock;
1880 }
1881 break;
1882 default:
1883 ret = LTTNG_ERR_UNK;
1884 goto error_unlock;
1885 }
1886
1887 kernel_wait_quiescent();
1888 break;
1889 }
1890 case LTTNG_DOMAIN_UST:
1891 {
1892 struct ltt_ust_channel *uchan;
1893 struct ltt_ust_session *usess;
1894
1895 usess = session->ust_session;
1896
1897 if (validate_ust_event_name(event_name)) {
1898 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1899 goto error_unlock;
1900 }
1901
1902 /*
1903 * If a non-default channel has been created in the
1904 * session, explicitly require that -c chan_name needs
1905 * to be provided.
1906 */
1907 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1908 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1909 goto error_unlock;
1910 }
1911
1912 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1913 channel_name);
1914 if (uchan == NULL) {
1915 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1916 goto error_unlock;
1917 }
1918
1919 switch (event->type) {
1920 case LTTNG_EVENT_ALL:
1921 /*
1922 * An empty event name means that everything
1923 * should be disabled.
1924 */
1925 if (event->name[0] == '\0') {
1926 ret = event_ust_disable_all_tracepoints(usess, uchan);
1927 } else {
1928 ret = event_ust_disable_tracepoint(usess, uchan,
1929 event_name);
1930 }
1931 if (ret != LTTNG_OK) {
1932 goto error_unlock;
1933 }
1934 break;
1935 default:
1936 ret = LTTNG_ERR_UNK;
1937 goto error_unlock;
1938 }
1939
1940 DBG3("Disable UST event %s in channel %s completed", event_name,
1941 channel_name);
1942 break;
1943 }
1944 case LTTNG_DOMAIN_LOG4J:
1945 case LTTNG_DOMAIN_JUL:
1946 case LTTNG_DOMAIN_PYTHON:
1947 {
1948 struct agent *agt;
1949 struct ltt_ust_session *usess = session->ust_session;
1950
1951 assert(usess);
1952
1953 switch (event->type) {
1954 case LTTNG_EVENT_ALL:
1955 break;
1956 default:
1957 ret = LTTNG_ERR_UNK;
1958 goto error_unlock;
1959 }
1960
1961 agt = trace_ust_find_agent(usess, domain);
1962 if (!agt) {
1963 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1964 goto error_unlock;
1965 }
1966 /*
1967 * An empty event name means that everything
1968 * should be disabled.
1969 */
1970 if (event->name[0] == '\0') {
1971 ret = event_agent_disable_all(usess, agt);
1972 } else {
1973 ret = event_agent_disable(usess, agt, event_name);
1974 }
1975 if (ret != LTTNG_OK) {
1976 goto error_unlock;
1977 }
1978
1979 break;
1980 }
1981 default:
1982 ret = LTTNG_ERR_UND;
1983 goto error_unlock;
1984 }
1985
1986 ret = LTTNG_OK;
1987
1988 error_unlock:
1989 rcu_read_unlock();
1990 error:
1991 return ret;
1992 }
1993
1994 /*
1995 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1996 */
1997 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1998 char *channel_name, const struct lttng_event_context *ctx, int kwpipe)
1999 {
2000 int ret, chan_kern_created = 0, chan_ust_created = 0;
2001 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
2002
2003 /*
2004 * Don't try to add a context if the session has been started at
2005 * some point in time before. The tracer does not allow it and would
2006 * result in a corrupted trace.
2007 */
2008 if (session->has_been_started) {
2009 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2010 goto end;
2011 }
2012
2013 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
2014 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
2015 app_ctx_name = ctx->u.app_ctx.ctx_name;
2016 }
2017
2018 switch (domain) {
2019 case LTTNG_DOMAIN_KERNEL:
2020 assert(session->kernel_session);
2021
2022 if (session->kernel_session->channel_count == 0) {
2023 /* Create default channel */
2024 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
2025 if (ret != LTTNG_OK) {
2026 goto error;
2027 }
2028 chan_kern_created = 1;
2029 }
2030 /* Add kernel context to kernel tracer */
2031 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
2032 if (ret != LTTNG_OK) {
2033 goto error;
2034 }
2035 break;
2036 case LTTNG_DOMAIN_JUL:
2037 case LTTNG_DOMAIN_LOG4J:
2038 {
2039 /*
2040 * Validate channel name.
2041 * If no channel name is given and the domain is JUL or LOG4J,
2042 * set it to the appropriate domain-specific channel name. If
2043 * a name is provided but does not match the expexted channel
2044 * name, return an error.
2045 */
2046 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
2047 strcmp(channel_name,
2048 DEFAULT_JUL_CHANNEL_NAME)) {
2049 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2050 goto error;
2051 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
2052 strcmp(channel_name,
2053 DEFAULT_LOG4J_CHANNEL_NAME)) {
2054 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2055 goto error;
2056 }
2057 /* break is _not_ missing here. */
2058 }
2059 case LTTNG_DOMAIN_UST:
2060 {
2061 struct ltt_ust_session *usess = session->ust_session;
2062 unsigned int chan_count;
2063
2064 assert(usess);
2065
2066 chan_count = lttng_ht_get_count(usess->domain_global.channels);
2067 if (chan_count == 0) {
2068 struct lttng_channel *attr;
2069 /* Create default channel */
2070 attr = channel_new_default_attr(domain, usess->buffer_type);
2071 if (attr == NULL) {
2072 ret = LTTNG_ERR_FATAL;
2073 goto error;
2074 }
2075
2076 ret = channel_ust_create(usess, attr, usess->buffer_type);
2077 if (ret != LTTNG_OK) {
2078 free(attr);
2079 goto error;
2080 }
2081 channel_attr_destroy(attr);
2082 chan_ust_created = 1;
2083 }
2084
2085 ret = context_ust_add(usess, domain, ctx, channel_name);
2086 free(app_ctx_provider_name);
2087 free(app_ctx_name);
2088 app_ctx_name = NULL;
2089 app_ctx_provider_name = NULL;
2090 if (ret != LTTNG_OK) {
2091 goto error;
2092 }
2093 break;
2094 }
2095 default:
2096 ret = LTTNG_ERR_UND;
2097 goto error;
2098 }
2099
2100 ret = LTTNG_OK;
2101 goto end;
2102
2103 error:
2104 if (chan_kern_created) {
2105 struct ltt_kernel_channel *kchan =
2106 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
2107 session->kernel_session);
2108 /* Created previously, this should NOT fail. */
2109 assert(kchan);
2110 kernel_destroy_channel(kchan);
2111 }
2112
2113 if (chan_ust_created) {
2114 struct ltt_ust_channel *uchan =
2115 trace_ust_find_channel_by_name(
2116 session->ust_session->domain_global.channels,
2117 DEFAULT_CHANNEL_NAME);
2118 /* Created previously, this should NOT fail. */
2119 assert(uchan);
2120 /* Remove from the channel list of the session. */
2121 trace_ust_delete_channel(session->ust_session->domain_global.channels,
2122 uchan);
2123 trace_ust_destroy_channel(uchan);
2124 }
2125 end:
2126 free(app_ctx_provider_name);
2127 free(app_ctx_name);
2128 return ret;
2129 }
2130
2131 static inline bool name_starts_with(const char *name, const char *prefix)
2132 {
2133 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
2134
2135 return !strncmp(name, prefix, max_cmp_len);
2136 }
2137
2138 /* Perform userspace-specific event name validation */
2139 static int validate_ust_event_name(const char *name)
2140 {
2141 int ret = 0;
2142
2143 if (!name) {
2144 ret = -1;
2145 goto end;
2146 }
2147
2148 /*
2149 * Check name against all internal UST event component namespaces used
2150 * by the agents.
2151 */
2152 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
2153 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
2154 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
2155 ret = -1;
2156 }
2157
2158 end:
2159 return ret;
2160 }
2161
2162 /*
2163 * Internal version of cmd_enable_event() with a supplemental
2164 * "internal_event" flag which is used to enable internal events which should
2165 * be hidden from clients. Such events are used in the agent implementation to
2166 * enable the events through which all "agent" events are funeled.
2167 */
2168 static int _cmd_enable_event(struct ltt_session *session,
2169 const struct lttng_domain *domain,
2170 char *channel_name, struct lttng_event *event,
2171 char *filter_expression,
2172 struct lttng_filter_bytecode *filter,
2173 struct lttng_event_exclusion *exclusion,
2174 int wpipe, bool internal_event)
2175 {
2176 int ret = 0, channel_created = 0;
2177 struct lttng_channel *attr = NULL;
2178
2179 assert(session);
2180 assert(event);
2181 assert(channel_name);
2182
2183 /* If we have a filter, we must have its filter expression */
2184 assert(!(!!filter_expression ^ !!filter));
2185
2186 /* Normalize event name as a globbing pattern */
2187 strutils_normalize_star_glob_pattern(event->name);
2188
2189 /* Normalize exclusion names as globbing patterns */
2190 if (exclusion) {
2191 size_t i;
2192
2193 for (i = 0; i < exclusion->count; i++) {
2194 char *name = LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
2195
2196 strutils_normalize_star_glob_pattern(name);
2197 }
2198 }
2199
2200 DBG("Enable event command for event \'%s\'", event->name);
2201
2202 rcu_read_lock();
2203
2204 switch (domain->type) {
2205 case LTTNG_DOMAIN_KERNEL:
2206 {
2207 struct ltt_kernel_channel *kchan;
2208
2209 /*
2210 * If a non-default channel has been created in the
2211 * session, explicitely require that -c chan_name needs
2212 * to be provided.
2213 */
2214 if (session->kernel_session->has_non_default_channel
2215 && channel_name[0] == '\0') {
2216 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2217 goto error;
2218 }
2219
2220 kchan = trace_kernel_get_channel_by_name(channel_name,
2221 session->kernel_session);
2222 if (kchan == NULL) {
2223 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
2224 LTTNG_BUFFER_GLOBAL);
2225 if (attr == NULL) {
2226 ret = LTTNG_ERR_FATAL;
2227 goto error;
2228 }
2229 if (lttng_strncpy(attr->name, channel_name,
2230 sizeof(attr->name))) {
2231 ret = LTTNG_ERR_INVALID;
2232 goto error;
2233 }
2234
2235 ret = cmd_enable_channel(session, domain, attr, wpipe);
2236 if (ret != LTTNG_OK) {
2237 goto error;
2238 }
2239 channel_created = 1;
2240 }
2241
2242 /* Get the newly created kernel channel pointer */
2243 kchan = trace_kernel_get_channel_by_name(channel_name,
2244 session->kernel_session);
2245 if (kchan == NULL) {
2246 /* This sould not happen... */
2247 ret = LTTNG_ERR_FATAL;
2248 goto error;
2249 }
2250
2251 switch (event->type) {
2252 case LTTNG_EVENT_ALL:
2253 {
2254 char *filter_expression_a = NULL;
2255 struct lttng_filter_bytecode *filter_a = NULL;
2256
2257 /*
2258 * We need to duplicate filter_expression and filter,
2259 * because ownership is passed to first enable
2260 * event.
2261 */
2262 if (filter_expression) {
2263 filter_expression_a = strdup(filter_expression);
2264 if (!filter_expression_a) {
2265 ret = LTTNG_ERR_FATAL;
2266 goto error;
2267 }
2268 }
2269 if (filter) {
2270 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
2271 if (!filter_a) {
2272 free(filter_expression_a);
2273 ret = LTTNG_ERR_FATAL;
2274 goto error;
2275 }
2276 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
2277 }
2278 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
2279 ret = event_kernel_enable_event(kchan, event,
2280 filter_expression, filter);
2281 /* We have passed ownership */
2282 filter_expression = NULL;
2283 filter = NULL;
2284 if (ret != LTTNG_OK) {
2285 if (channel_created) {
2286 /* Let's not leak a useless channel. */
2287 kernel_destroy_channel(kchan);
2288 }
2289 free(filter_expression_a);
2290 free(filter_a);
2291 goto error;
2292 }
2293 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
2294 ret = event_kernel_enable_event(kchan, event,
2295 filter_expression_a, filter_a);
2296 /* We have passed ownership */
2297 filter_expression_a = NULL;
2298 filter_a = NULL;
2299 if (ret != LTTNG_OK) {
2300 goto error;
2301 }
2302 break;
2303 }
2304 case LTTNG_EVENT_PROBE:
2305 case LTTNG_EVENT_USERSPACE_PROBE:
2306 case LTTNG_EVENT_FUNCTION:
2307 case LTTNG_EVENT_FUNCTION_ENTRY:
2308 case LTTNG_EVENT_TRACEPOINT:
2309 ret = event_kernel_enable_event(kchan, event,
2310 filter_expression, filter);
2311 /* We have passed ownership */
2312 filter_expression = NULL;
2313 filter = NULL;
2314 if (ret != LTTNG_OK) {
2315 if (channel_created) {
2316 /* Let's not leak a useless channel. */
2317 kernel_destroy_channel(kchan);
2318 }
2319 goto error;
2320 }
2321 break;
2322 case LTTNG_EVENT_SYSCALL:
2323 ret = event_kernel_enable_event(kchan, event,
2324 filter_expression, filter);
2325 /* We have passed ownership */
2326 filter_expression = NULL;
2327 filter = NULL;
2328 if (ret != LTTNG_OK) {
2329 goto error;
2330 }
2331 break;
2332 default:
2333 ret = LTTNG_ERR_UNK;
2334 goto error;
2335 }
2336
2337 kernel_wait_quiescent();
2338 break;
2339 }
2340 case LTTNG_DOMAIN_UST:
2341 {
2342 struct ltt_ust_channel *uchan;
2343 struct ltt_ust_session *usess = session->ust_session;
2344
2345 assert(usess);
2346
2347 /*
2348 * If a non-default channel has been created in the
2349 * session, explicitely require that -c chan_name needs
2350 * to be provided.
2351 */
2352 if (usess->has_non_default_channel && channel_name[0] == '\0') {
2353 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2354 goto error;
2355 }
2356
2357 /* Get channel from global UST domain */
2358 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2359 channel_name);
2360 if (uchan == NULL) {
2361 /* Create default channel */
2362 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
2363 usess->buffer_type);
2364 if (attr == NULL) {
2365 ret = LTTNG_ERR_FATAL;
2366 goto error;
2367 }
2368 if (lttng_strncpy(attr->name, channel_name,
2369 sizeof(attr->name))) {
2370 ret = LTTNG_ERR_INVALID;
2371 goto error;
2372 }
2373
2374 ret = cmd_enable_channel(session, domain, attr, wpipe);
2375 if (ret != LTTNG_OK) {
2376 goto error;
2377 }
2378
2379 /* Get the newly created channel reference back */
2380 uchan = trace_ust_find_channel_by_name(
2381 usess->domain_global.channels, channel_name);
2382 assert(uchan);
2383 }
2384
2385 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2386 /*
2387 * Don't allow users to add UST events to channels which
2388 * are assigned to a userspace subdomain (JUL, Log4J,
2389 * Python, etc.).
2390 */
2391 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2392 goto error;
2393 }
2394
2395 if (!internal_event) {
2396 /*
2397 * Ensure the event name is not reserved for internal
2398 * use.
2399 */
2400 ret = validate_ust_event_name(event->name);
2401 if (ret) {
2402 WARN("Userspace event name %s failed validation.",
2403 event->name);
2404 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2405 goto error;
2406 }
2407 }
2408
2409 /* At this point, the session and channel exist on the tracer */
2410 ret = event_ust_enable_tracepoint(usess, uchan, event,
2411 filter_expression, filter, exclusion,
2412 internal_event);
2413 /* We have passed ownership */
2414 filter_expression = NULL;
2415 filter = NULL;
2416 exclusion = NULL;
2417 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2418 goto already_enabled;
2419 } else if (ret != LTTNG_OK) {
2420 goto error;
2421 }
2422 break;
2423 }
2424 case LTTNG_DOMAIN_LOG4J:
2425 case LTTNG_DOMAIN_JUL:
2426 case LTTNG_DOMAIN_PYTHON:
2427 {
2428 const char *default_event_name, *default_chan_name;
2429 struct agent *agt;
2430 struct lttng_event uevent;
2431 struct lttng_domain tmp_dom;
2432 struct ltt_ust_session *usess = session->ust_session;
2433
2434 assert(usess);
2435
2436 if (!agent_tracing_is_enabled()) {
2437 DBG("Attempted to enable an event in an agent domain but the agent thread is not running");
2438 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
2439 goto error;
2440 }
2441
2442 agt = trace_ust_find_agent(usess, domain->type);
2443 if (!agt) {
2444 agt = agent_create(domain->type);
2445 if (!agt) {
2446 ret = LTTNG_ERR_NOMEM;
2447 goto error;
2448 }
2449 agent_add(agt, usess->agents);
2450 }
2451
2452 /* Create the default tracepoint. */
2453 memset(&uevent, 0, sizeof(uevent));
2454 uevent.type = LTTNG_EVENT_TRACEPOINT;
2455 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2456 default_event_name = event_get_default_agent_ust_name(
2457 domain->type);
2458 if (!default_event_name) {
2459 ret = LTTNG_ERR_FATAL;
2460 goto error;
2461 }
2462 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2463 uevent.name[sizeof(uevent.name) - 1] = '\0';
2464
2465 /*
2466 * The domain type is changed because we are about to enable the
2467 * default channel and event for the JUL domain that are hardcoded.
2468 * This happens in the UST domain.
2469 */
2470 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2471 tmp_dom.type = LTTNG_DOMAIN_UST;
2472
2473 switch (domain->type) {
2474 case LTTNG_DOMAIN_LOG4J:
2475 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2476 break;
2477 case LTTNG_DOMAIN_JUL:
2478 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2479 break;
2480 case LTTNG_DOMAIN_PYTHON:
2481 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2482 break;
2483 default:
2484 /* The switch/case we are in makes this impossible */
2485 assert(0);
2486 }
2487
2488 {
2489 char *filter_expression_copy = NULL;
2490 struct lttng_filter_bytecode *filter_copy = NULL;
2491
2492 if (filter) {
2493 const size_t filter_size = sizeof(
2494 struct lttng_filter_bytecode)
2495 + filter->len;
2496
2497 filter_copy = zmalloc(filter_size);
2498 if (!filter_copy) {
2499 ret = LTTNG_ERR_NOMEM;
2500 goto error;
2501 }
2502 memcpy(filter_copy, filter, filter_size);
2503
2504 filter_expression_copy =
2505 strdup(filter_expression);
2506 if (!filter_expression) {
2507 ret = LTTNG_ERR_NOMEM;
2508 }
2509
2510 if (!filter_expression_copy || !filter_copy) {
2511 free(filter_expression_copy);
2512 free(filter_copy);
2513 goto error;
2514 }
2515 }
2516
2517 ret = cmd_enable_event_internal(session, &tmp_dom,
2518 (char *) default_chan_name,
2519 &uevent, filter_expression_copy,
2520 filter_copy, NULL, wpipe);
2521 }
2522
2523 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2524 goto already_enabled;
2525 } else if (ret != LTTNG_OK) {
2526 goto error;
2527 }
2528
2529 /* The wild card * means that everything should be enabled. */
2530 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2531 ret = event_agent_enable_all(usess, agt, event, filter,
2532 filter_expression);
2533 } else {
2534 ret = event_agent_enable(usess, agt, event, filter,
2535 filter_expression);
2536 }
2537 filter = NULL;
2538 filter_expression = NULL;
2539 if (ret != LTTNG_OK) {
2540 goto error;
2541 }
2542
2543 break;
2544 }
2545 default:
2546 ret = LTTNG_ERR_UND;
2547 goto error;
2548 }
2549
2550 ret = LTTNG_OK;
2551
2552 already_enabled:
2553 error:
2554 free(filter_expression);
2555 free(filter);
2556 free(exclusion);
2557 channel_attr_destroy(attr);
2558 rcu_read_unlock();
2559 return ret;
2560 }
2561
2562 /*
2563 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2564 * We own filter, exclusion, and filter_expression.
2565 */
2566 int cmd_enable_event(struct ltt_session *session,
2567 const struct lttng_domain *domain,
2568 char *channel_name, struct lttng_event *event,
2569 char *filter_expression,
2570 struct lttng_filter_bytecode *filter,
2571 struct lttng_event_exclusion *exclusion,
2572 int wpipe)
2573 {
2574 return _cmd_enable_event(session, domain, channel_name, event,
2575 filter_expression, filter, exclusion, wpipe, false);
2576 }
2577
2578 /*
2579 * Enable an event which is internal to LTTng. An internal should
2580 * never be made visible to clients and are immune to checks such as
2581 * reserved names.
2582 */
2583 static int cmd_enable_event_internal(struct ltt_session *session,
2584 const struct lttng_domain *domain,
2585 char *channel_name, struct lttng_event *event,
2586 char *filter_expression,
2587 struct lttng_filter_bytecode *filter,
2588 struct lttng_event_exclusion *exclusion,
2589 int wpipe)
2590 {
2591 return _cmd_enable_event(session, domain, channel_name, event,
2592 filter_expression, filter, exclusion, wpipe, true);
2593 }
2594
2595 /*
2596 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2597 */
2598 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2599 struct lttng_event **events)
2600 {
2601 int ret;
2602 ssize_t nb_events = 0;
2603
2604 switch (domain) {
2605 case LTTNG_DOMAIN_KERNEL:
2606 nb_events = kernel_list_events(events);
2607 if (nb_events < 0) {
2608 ret = LTTNG_ERR_KERN_LIST_FAIL;
2609 goto error;
2610 }
2611 break;
2612 case LTTNG_DOMAIN_UST:
2613 nb_events = ust_app_list_events(events);
2614 if (nb_events < 0) {
2615 ret = LTTNG_ERR_UST_LIST_FAIL;
2616 goto error;
2617 }
2618 break;
2619 case LTTNG_DOMAIN_LOG4J:
2620 case LTTNG_DOMAIN_JUL:
2621 case LTTNG_DOMAIN_PYTHON:
2622 nb_events = agent_list_events(events, domain);
2623 if (nb_events < 0) {
2624 ret = LTTNG_ERR_UST_LIST_FAIL;
2625 goto error;
2626 }
2627 break;
2628 default:
2629 ret = LTTNG_ERR_UND;
2630 goto error;
2631 }
2632
2633 return nb_events;
2634
2635 error:
2636 /* Return negative value to differentiate return code */
2637 return -ret;
2638 }
2639
2640 /*
2641 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2642 */
2643 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2644 struct lttng_event_field **fields)
2645 {
2646 int ret;
2647 ssize_t nb_fields = 0;
2648
2649 switch (domain) {
2650 case LTTNG_DOMAIN_UST:
2651 nb_fields = ust_app_list_event_fields(fields);
2652 if (nb_fields < 0) {
2653 ret = LTTNG_ERR_UST_LIST_FAIL;
2654 goto error;
2655 }
2656 break;
2657 case LTTNG_DOMAIN_KERNEL:
2658 default: /* fall-through */
2659 ret = LTTNG_ERR_UND;
2660 goto error;
2661 }
2662
2663 return nb_fields;
2664
2665 error:
2666 /* Return negative value to differentiate return code */
2667 return -ret;
2668 }
2669
2670 ssize_t cmd_list_syscalls(struct lttng_event **events)
2671 {
2672 return syscall_table_list(events);
2673 }
2674
2675 /*
2676 * Command LTTNG_START_TRACE processed by the client thread.
2677 *
2678 * Called with session mutex held.
2679 */
2680 int cmd_start_trace(struct ltt_session *session)
2681 {
2682 enum lttng_error_code ret;
2683 unsigned long nb_chan = 0;
2684 struct ltt_kernel_session *ksession;
2685 struct ltt_ust_session *usess;
2686 const bool session_rotated_after_last_stop =
2687 session->rotated_after_last_stop;
2688 const bool session_cleared_after_last_stop =
2689 session->cleared_after_last_stop;
2690
2691 assert(session);
2692
2693 /* Ease our life a bit ;) */
2694 ksession = session->kernel_session;
2695 usess = session->ust_session;
2696
2697 /* Is the session already started? */
2698 if (session->active) {
2699 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2700 /* Perform nothing */
2701 goto end;
2702 }
2703
2704 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING &&
2705 !session->current_trace_chunk) {
2706 /*
2707 * A rotation was launched while the session was stopped and
2708 * it has not been completed yet. It is not possible to start
2709 * the session since starting the session here would require a
2710 * rotation from "NULL" to a new trace chunk. That rotation
2711 * would overlap with the ongoing rotation, which is not
2712 * supported.
2713 */
2714 WARN("Refusing to start session \"%s\" as a rotation launched after the last \"stop\" is still ongoing",
2715 session->name);
2716 ret = LTTNG_ERR_ROTATION_PENDING;
2717 goto error;
2718 }
2719
2720 /*
2721 * Starting a session without channel is useless since after that it's not
2722 * possible to enable channel thus inform the client.
2723 */
2724 if (usess && usess->domain_global.channels) {
2725 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2726 }
2727 if (ksession) {
2728 nb_chan += ksession->channel_count;
2729 }
2730 if (!nb_chan) {
2731 ret = LTTNG_ERR_NO_CHANNEL;
2732 goto error;
2733 }
2734
2735 session->active = 1;
2736 session->rotated_after_last_stop = false;
2737 session->cleared_after_last_stop = false;
2738 if (session->output_traces && !session->current_trace_chunk) {
2739 if (!session->has_been_started) {
2740 struct lttng_trace_chunk *trace_chunk;
2741
2742 DBG("Creating initial trace chunk of session \"%s\"",
2743 session->name);
2744 trace_chunk = session_create_new_trace_chunk(
2745 session, NULL, NULL, NULL);
2746 if (!trace_chunk) {
2747 ret = LTTNG_ERR_CREATE_DIR_FAIL;
2748 goto error;
2749 }
2750 assert(!session->current_trace_chunk);
2751 ret = session_set_trace_chunk(session, trace_chunk,
2752 NULL);
2753 lttng_trace_chunk_put(trace_chunk);
2754 if (ret) {
2755 ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
2756 goto error;
2757 }
2758 } else {
2759 DBG("Rotating session \"%s\" from its current \"NULL\" trace chunk to a new chunk",
2760 session->name);
2761 /*
2762 * Rotate existing streams into the new chunk.
2763 * This is a "quiet" rotation has no client has
2764 * explicitly requested this operation.
2765 *
2766 * There is also no need to wait for the rotation
2767 * to complete as it will happen immediately. No data
2768 * was produced as the session was stopped, so the
2769 * rotation should happen on reception of the command.
2770 */
2771 ret = cmd_rotate_session(session, NULL, true,
2772 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
2773 if (ret != LTTNG_OK) {
2774 goto error;
2775 }
2776 }
2777 }
2778
2779 /* Kernel tracing */
2780 if (ksession != NULL) {
2781 DBG("Start kernel tracing session %s", session->name);
2782 ret = start_kernel_session(ksession);
2783 if (ret != LTTNG_OK) {
2784 goto error;
2785 }
2786 }
2787
2788 /* Flag session that trace should start automatically */
2789 if (usess) {
2790 int int_ret = ust_app_start_trace_all(usess);
2791
2792 if (int_ret < 0) {
2793 ret = LTTNG_ERR_UST_START_FAIL;
2794 goto error;
2795 }
2796 }
2797
2798 /*
2799 * Open a packet in every stream of the session to ensure that viewers
2800 * can correctly identify the boundaries of the periods during which
2801 * tracing was active for this session.
2802 */
2803 ret = session_open_packets(session);
2804 if (ret != LTTNG_OK) {
2805 goto error;
2806 }
2807
2808 /*
2809 * Clear the flag that indicates that a rotation was done while the
2810 * session was stopped.
2811 */
2812 session->rotated_after_last_stop = false;
2813
2814 if (session->rotate_timer_period) {
2815 int int_ret = timer_session_rotation_schedule_timer_start(
2816 session, session->rotate_timer_period);
2817
2818 if (int_ret < 0) {
2819 ERR("Failed to enable rotate timer");
2820 ret = LTTNG_ERR_UNK;
2821 goto error;
2822 }
2823 }
2824
2825 ret = LTTNG_OK;
2826
2827 error:
2828 if (ret == LTTNG_OK) {
2829 /* Flag this after a successful start. */
2830 session->has_been_started |= 1;
2831 } else {
2832 session->active = 0;
2833 /* Restore initial state on error. */
2834 session->rotated_after_last_stop =
2835 session_rotated_after_last_stop;
2836 session->cleared_after_last_stop =
2837 session_cleared_after_last_stop;
2838 }
2839 end:
2840 return ret;
2841 }
2842
2843 /*
2844 * Command LTTNG_STOP_TRACE processed by the client thread.
2845 */
2846 int cmd_stop_trace(struct ltt_session *session)
2847 {
2848 int ret;
2849 struct ltt_kernel_session *ksession;
2850 struct ltt_ust_session *usess;
2851
2852 assert(session);
2853
2854 DBG("Begin stop session \"%s\" (id %" PRIu64 ")", session->name, session->id);
2855 /* Short cut */
2856 ksession = session->kernel_session;
2857 usess = session->ust_session;
2858
2859 /* Session is not active. Skip everythong and inform the client. */
2860 if (!session->active) {
2861 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2862 goto error;
2863 }
2864
2865 ret = stop_kernel_session(ksession);
2866 if (ret != LTTNG_OK) {
2867 goto error;
2868 }
2869
2870 if (usess && usess->active) {
2871 ret = ust_app_stop_trace_all(usess);
2872 if (ret < 0) {
2873 ret = LTTNG_ERR_UST_STOP_FAIL;
2874 goto error;
2875 }
2876 }
2877
2878 DBG("Completed stop session \"%s\" (id %" PRIu64 ")", session->name,
2879 session->id);
2880 /* Flag inactive after a successful stop. */
2881 session->active = 0;
2882 ret = LTTNG_OK;
2883
2884 error:
2885 return ret;
2886 }
2887
2888 /*
2889 * Set the base_path of the session only if subdir of a control uris is set.
2890 * Return LTTNG_OK on success, otherwise LTTNG_ERR_*.
2891 */
2892 static int set_session_base_path_from_uris(struct ltt_session *session,
2893 size_t nb_uri,
2894 struct lttng_uri *uris)
2895 {
2896 int ret;
2897 size_t i;
2898
2899 for (i = 0; i < nb_uri; i++) {
2900 if (uris[i].stype != LTTNG_STREAM_CONTROL ||
2901 uris[i].subdir[0] == '\0') {
2902 /* Not interested in these URIs */
2903 continue;
2904 }
2905
2906 if (session->base_path != NULL) {
2907 free(session->base_path);
2908 session->base_path = NULL;
2909 }
2910
2911 /* Set session base_path */
2912 session->base_path = strdup(uris[i].subdir);
2913 if (!session->base_path) {
2914 PERROR("Failed to copy base path \"%s\" to session \"%s\"",
2915 uris[i].subdir, session->name);
2916 ret = LTTNG_ERR_NOMEM;
2917 goto error;
2918 }
2919 DBG2("Setting base path \"%s\" for session \"%s\"",
2920 session->base_path, session->name);
2921 }
2922 ret = LTTNG_OK;
2923 error:
2924 return ret;
2925 }
2926
2927 /*
2928 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2929 */
2930 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2931 struct lttng_uri *uris)
2932 {
2933 int ret, i;
2934 struct ltt_kernel_session *ksess = session->kernel_session;
2935 struct ltt_ust_session *usess = session->ust_session;
2936
2937 assert(session);
2938 assert(uris);
2939 assert(nb_uri > 0);
2940
2941 /* Can't set consumer URI if the session is active. */
2942 if (session->active) {
2943 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2944 goto error;
2945 }
2946
2947 /*
2948 * Set the session base path if any. This is done inside
2949 * cmd_set_consumer_uri to preserve backward compatibility of the
2950 * previous session creation api vs the session descriptor api.
2951 */
2952 ret = set_session_base_path_from_uris(session, nb_uri, uris);
2953 if (ret != LTTNG_OK) {
2954 goto error;
2955 }
2956
2957 /* Set the "global" consumer URIs */
2958 for (i = 0; i < nb_uri; i++) {
2959 ret = add_uri_to_consumer(session, session->consumer, &uris[i],
2960 LTTNG_DOMAIN_NONE);
2961 if (ret != LTTNG_OK) {
2962 goto error;
2963 }
2964 }
2965
2966 /* Set UST session URIs */
2967 if (session->ust_session) {
2968 for (i = 0; i < nb_uri; i++) {
2969 ret = add_uri_to_consumer(session,
2970 session->ust_session->consumer,
2971 &uris[i], LTTNG_DOMAIN_UST);
2972 if (ret != LTTNG_OK) {
2973 goto error;
2974 }
2975 }
2976 }
2977
2978 /* Set kernel session URIs */
2979 if (session->kernel_session) {
2980 for (i = 0; i < nb_uri; i++) {
2981 ret = add_uri_to_consumer(session,
2982 session->kernel_session->consumer,
2983 &uris[i], LTTNG_DOMAIN_KERNEL);
2984 if (ret != LTTNG_OK) {
2985 goto error;
2986 }
2987 }
2988 }
2989
2990 /*
2991 * Make sure to set the session in output mode after we set URI since a
2992 * session can be created without URL (thus flagged in no output mode).
2993 */
2994 session->output_traces = 1;
2995 if (ksess) {
2996 ksess->output_traces = 1;
2997 }
2998
2999 if (usess) {
3000 usess->output_traces = 1;
3001 }
3002
3003 /* All good! */
3004 ret = LTTNG_OK;
3005
3006 error:
3007 return ret;
3008 }
3009
3010 static
3011 enum lttng_error_code set_session_output_from_descriptor(
3012 struct ltt_session *session,
3013 const struct lttng_session_descriptor *descriptor)
3014 {
3015 int ret;
3016 enum lttng_error_code ret_code = LTTNG_OK;
3017 enum lttng_session_descriptor_type session_type =
3018 lttng_session_descriptor_get_type(descriptor);
3019 enum lttng_session_descriptor_output_type output_type =
3020 lttng_session_descriptor_get_output_type(descriptor);
3021 struct lttng_uri uris[2] = {};
3022 size_t uri_count = 0;
3023
3024 switch (output_type) {
3025 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NONE:
3026 goto end;
3027 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_LOCAL:
3028 lttng_session_descriptor_get_local_output_uri(descriptor,
3029 &uris[0]);
3030 uri_count = 1;
3031 break;
3032 case LTTNG_SESSION_DESCRIPTOR_OUTPUT_TYPE_NETWORK:
3033 lttng_session_descriptor_get_network_output_uris(descriptor,
3034 &uris[0], &uris[1]);
3035 uri_count = 2;
3036 break;
3037 default:
3038 ret_code = LTTNG_ERR_INVALID;
3039 goto end;
3040 }
3041
3042 switch (session_type) {
3043 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
3044 {
3045 struct snapshot_output *new_output = NULL;
3046
3047 new_output = snapshot_output_alloc();
3048 if (!new_output) {
3049 ret_code = LTTNG_ERR_NOMEM;
3050 goto end;
3051 }
3052
3053 ret = snapshot_output_init_with_uri(session,
3054 DEFAULT_SNAPSHOT_MAX_SIZE,
3055 NULL, uris, uri_count, session->consumer,
3056 new_output, &session->snapshot);
3057 if (ret < 0) {
3058 ret_code = (ret == -ENOMEM) ?
3059 LTTNG_ERR_NOMEM : LTTNG_ERR_INVALID;
3060 snapshot_output_destroy(new_output);
3061 goto end;
3062 }
3063 snapshot_add_output(&session->snapshot, new_output);
3064 break;
3065 }
3066 case LTTNG_SESSION_DESCRIPTOR_TYPE_REGULAR:
3067 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3068 {
3069 ret_code = cmd_set_consumer_uri(session, uri_count, uris);
3070 break;
3071 }
3072 default:
3073 ret_code = LTTNG_ERR_INVALID;
3074 goto end;
3075 }
3076 end:
3077 return ret_code;
3078 }
3079
3080 static
3081 enum lttng_error_code cmd_create_session_from_descriptor(
3082 struct lttng_session_descriptor *descriptor,
3083 const lttng_sock_cred *creds,
3084 const char *home_path)
3085 {
3086 int ret;
3087 enum lttng_error_code ret_code;
3088 const char *session_name;
3089 struct ltt_session *new_session = NULL;
3090 enum lttng_session_descriptor_status descriptor_status;
3091
3092 session_lock_list();
3093 if (home_path) {
3094 if (*home_path != '/') {
3095 ERR("Home path provided by client is not absolute");
3096 ret_code = LTTNG_ERR_INVALID;
3097 goto end;
3098 }
3099 }
3100
3101 descriptor_status = lttng_session_descriptor_get_session_name(
3102 descriptor, &session_name);
3103 switch (descriptor_status) {
3104 case LTTNG_SESSION_DESCRIPTOR_STATUS_OK:
3105 break;
3106 case LTTNG_SESSION_DESCRIPTOR_STATUS_UNSET:
3107 session_name = NULL;
3108 break;
3109 default:
3110 ret_code = LTTNG_ERR_INVALID;
3111 goto end;
3112 }
3113
3114 ret_code = session_create(session_name, creds->uid, creds->gid,
3115 &new_session);
3116 if (ret_code != LTTNG_OK) {
3117 goto end;
3118 }
3119
3120 if (!session_name) {
3121 ret = lttng_session_descriptor_set_session_name(descriptor,
3122 new_session->name);
3123 if (ret) {
3124 ret_code = LTTNG_ERR_SESSION_FAIL;
3125 goto end;
3126 }
3127 }
3128
3129 if (!lttng_session_descriptor_is_output_destination_initialized(
3130 descriptor)) {
3131 /*
3132 * Only include the session's creation time in the output
3133 * destination if the name of the session itself was
3134 * not auto-generated.
3135 */
3136 ret_code = lttng_session_descriptor_set_default_output(
3137 descriptor,
3138 session_name ? &new_session->creation_time : NULL,
3139 home_path);
3140 if (ret_code != LTTNG_OK) {
3141 goto end;
3142 }
3143 } else {
3144 new_session->has_user_specified_directory =
3145 lttng_session_descriptor_has_output_directory(
3146 descriptor);
3147 }
3148
3149 switch (lttng_session_descriptor_get_type(descriptor)) {
3150 case LTTNG_SESSION_DESCRIPTOR_TYPE_SNAPSHOT:
3151 new_session->snapshot_mode = 1;
3152 break;
3153 case LTTNG_SESSION_DESCRIPTOR_TYPE_LIVE:
3154 new_session->live_timer =
3155 lttng_session_descriptor_live_get_timer_interval(
3156 descriptor);
3157 break;
3158 default:
3159 break;
3160 }
3161
3162 ret_code = set_session_output_from_descriptor(new_session, descriptor);
3163 if (ret_code != LTTNG_OK) {
3164 goto end;
3165 }
3166 new_session->consumer->enabled = 1;
3167 ret_code = LTTNG_OK;
3168 end:
3169 /* Release reference provided by the session_create function. */
3170 session_put(new_session);
3171 if (ret_code != LTTNG_OK && new_session) {
3172 /* Release the global reference on error. */
3173 session_destroy(new_session);
3174 }
3175 session_unlock_list();
3176 return ret_code;
3177 }
3178
3179 enum lttng_error_code cmd_create_session(struct command_ctx *cmd_ctx, int sock,
3180 struct lttng_session_descriptor **return_descriptor)
3181 {
3182 int ret;
3183 size_t payload_size;
3184 struct lttng_dynamic_buffer payload;
3185 struct lttng_buffer_view home_dir_view;
3186 struct lttng_buffer_view session_descriptor_view;
3187 struct lttng_session_descriptor *session_descriptor = NULL;
3188 enum lttng_error_code ret_code;
3189
3190 lttng_dynamic_buffer_init(&payload);
3191 if (cmd_ctx->lsm->u.create_session.home_dir_size >=
3192 LTTNG_PATH_MAX) {
3193 ret_code = LTTNG_ERR_INVALID;
3194 goto error;
3195 }
3196 if (cmd_ctx->lsm->u.create_session.session_descriptor_size >
3197 LTTNG_SESSION_DESCRIPTOR_MAX_LEN) {
3198 ret_code = LTTNG_ERR_INVALID;
3199 goto error;
3200 }
3201
3202 payload_size = cmd_ctx->lsm->u.create_session.home_dir_size +
3203 cmd_ctx->lsm->u.create_session.session_descriptor_size;
3204 ret = lttng_dynamic_buffer_set_size(&payload, payload_size);
3205 if (ret) {
3206 ret_code = LTTNG_ERR_NOMEM;
3207 goto error;
3208 }
3209
3210 ret = lttcomm_recv_unix_sock(sock, payload.data, payload.size);
3211 if (ret <= 0) {
3212 ERR("Reception of session descriptor failed, aborting.");
3213 ret_code = LTTNG_ERR_SESSION_FAIL;
3214 goto error;
3215 }
3216
3217 home_dir_view = lttng_buffer_view_from_dynamic_buffer(
3218 &payload,
3219 0,
3220 cmd_ctx->lsm->u.create_session.home_dir_size);
3221 session_descriptor_view = lttng_buffer_view_from_dynamic_buffer(
3222 &payload,
3223 cmd_ctx->lsm->u.create_session.home_dir_size,
3224 cmd_ctx->lsm->u.create_session.session_descriptor_size);
3225
3226 ret = lttng_session_descriptor_create_from_buffer(
3227 &session_descriptor_view, &session_descriptor);
3228 if (ret < 0) {
3229 ERR("Failed to create session descriptor from payload of \"create session\" command");
3230 ret_code = LTTNG_ERR_INVALID;
3231 goto error;
3232 }
3233
3234 /*
3235 * Sets the descriptor's auto-generated properties (name, output) if
3236 * needed.
3237 */
3238 ret_code = cmd_create_session_from_descriptor(session_descriptor,
3239 &cmd_ctx->creds,
3240 home_dir_view.size ? home_dir_view.data : NULL);
3241 if (ret_code != LTTNG_OK) {
3242 goto error;
3243 }
3244
3245 ret_code = LTTNG_OK;
3246 *return_descriptor = session_descriptor;
3247 session_descriptor = NULL;
3248 error:
3249 lttng_dynamic_buffer_reset(&payload);
3250 lttng_session_descriptor_destroy(session_descriptor);
3251 return ret_code;
3252 }
3253
3254 static
3255 void cmd_destroy_session_reply(const struct ltt_session *session,
3256 void *_reply_context)
3257 {
3258 int ret;
3259 ssize_t comm_ret;
3260 const struct cmd_destroy_session_reply_context *reply_context =
3261 _reply_context;
3262 struct lttng_dynamic_buffer payload;
3263 struct lttcomm_session_destroy_command_header cmd_header;
3264 struct lttng_trace_archive_location *location = NULL;
3265 struct lttcomm_lttng_msg llm = {
3266 .cmd_type = LTTNG_DESTROY_SESSION,
3267 .ret_code = reply_context->destruction_status,
3268 .pid = UINT32_MAX,
3269 .cmd_header_size =
3270 sizeof(struct lttcomm_session_destroy_command_header),
3271 .data_size = 0,
3272 };
3273 size_t payload_size_before_location;
3274
3275 lttng_dynamic_buffer_init(&payload);
3276
3277 ret = lttng_dynamic_buffer_append(&payload, &llm, sizeof(llm));
3278 if (ret) {
3279 ERR("Failed to append session destruction message");
3280 goto error;
3281 }
3282
3283 cmd_header.rotation_state =
3284 (int32_t) (reply_context->implicit_rotation_on_destroy ?
3285 session->rotation_state :
3286 LTTNG_ROTATION_STATE_NO_ROTATION);
3287 ret = lttng_dynamic_buffer_append(&payload, &cmd_header,
3288 sizeof(cmd_header));
3289 if (ret) {
3290 ERR("Failed to append session destruction command header");
3291 goto error;
3292 }
3293
3294 if (!reply_context->implicit_rotation_on_destroy) {
3295 DBG("No implicit rotation performed during the destruction of session \"%s\", sending reply",
3296 session->name);
3297 goto send_reply;
3298 }
3299 if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED) {
3300 DBG("Rotation state of session \"%s\" is not \"completed\", sending session destruction reply",
3301 session->name);
3302 goto send_reply;
3303 }
3304
3305 location = session_get_trace_archive_location(session);
3306 if (!location) {
3307 ERR("Failed to get the location of the trace archive produced during the destruction of session \"%s\"",
3308 session->name);
3309 goto error;
3310 }
3311
3312 payload_size_before_location = payload.size;
3313 comm_ret = lttng_trace_archive_location_serialize(location,
3314 &payload);
3315 lttng_trace_archive_location_put(location);
3316 if (comm_ret < 0) {
3317 ERR("Failed to serialize the location of the trace archive produced during the destruction of session \"%s\"",
3318 session->name);
3319 goto error;
3320 }
3321 /* Update the message to indicate the location's length. */
3322 ((struct lttcomm_lttng_msg *) payload.data)->data_size =
3323 payload.size - payload_size_before_location;
3324 send_reply:
3325 comm_ret = lttcomm_send_unix_sock(reply_context->reply_sock_fd,
3326 payload.data, payload.size);
3327 if (comm_ret != (ssize_t) payload.size) {
3328 ERR("Failed to send result of the destruction of session \"%s\" to client",
3329 session->name);
3330 }
3331 error:
3332 ret = close(reply_context->reply_sock_fd);
3333 if (ret) {
3334 PERROR("Failed to close client socket in deferred session destroy reply");
3335 }
3336 lttng_dynamic_buffer_reset(&payload);
3337 free(_reply_context);
3338 }
3339
3340 /*
3341 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3342 *
3343 * Called with session lock held.
3344 */
3345 int cmd_destroy_session(struct ltt_session *session,
3346 struct notification_thread_handle *notification_thread_handle,
3347 int *sock_fd)
3348 {
3349 int ret;
3350 enum lttng_error_code destruction_last_error = LTTNG_OK;
3351 struct cmd_destroy_session_reply_context *reply_context = NULL;
3352
3353 if (sock_fd) {
3354 reply_context = zmalloc(sizeof(*reply_context));
3355 if (!reply_context) {
3356 ret = LTTNG_ERR_NOMEM;
3357 goto end;
3358 }
3359 reply_context->reply_sock_fd = *sock_fd;
3360 }
3361
3362 /* Safety net */
3363 assert(session);
3364
3365 DBG("Begin destroy session %s (id %" PRIu64 ")", session->name,
3366 session->id);
3367 if (session->active) {
3368 DBG("Session \"%s\" is active, attempting to stop it before destroying it",
3369 session->name);
3370 ret = cmd_stop_trace(session);
3371 if (ret != LTTNG_OK && ret != LTTNG_ERR_TRACE_ALREADY_STOPPED) {
3372 /* Carry on with the destruction of the session. */
3373 ERR("Failed to stop session \"%s\" as part of its destruction: %s",
3374 session->name, lttng_strerror(-ret));
3375 destruction_last_error = ret;
3376 }
3377 }
3378
3379 if (session->rotation_schedule_timer_enabled) {
3380 if (timer_session_rotation_schedule_timer_stop(
3381 session)) {
3382 ERR("Failed to stop the \"rotation schedule\" timer of session %s",
3383 session->name);
3384 destruction_last_error = LTTNG_ERR_TIMER_STOP_ERROR;
3385 }
3386 }
3387
3388 if (session->rotate_size) {
3389 unsubscribe_session_consumed_size_rotation(session, notification_thread_handle);
3390 session->rotate_size = 0;
3391 }
3392
3393 if (session->rotated && session->current_trace_chunk && session->output_traces) {
3394 /*
3395 * Perform a last rotation on destruction if rotations have
3396 * occurred during the session's lifetime.
3397 */
3398 ret = cmd_rotate_session(session, NULL, false,
3399 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
3400 if (ret != LTTNG_OK) {
3401 ERR("Failed to perform an implicit rotation as part of the destruction of session \"%s\": %s",
3402 session->name, lttng_strerror(-ret));
3403 destruction_last_error = -ret;
3404 }
3405 if (reply_context) {
3406 reply_context->implicit_rotation_on_destroy = true;
3407 }
3408 } else if (session->has_been_started && session->current_trace_chunk) {
3409 /*
3410 * The user has not triggered a session rotation. However, to
3411 * ensure all data has been consumed, the session is rotated
3412 * to a 'null' trace chunk before it is destroyed.
3413 *
3414 * This is a "quiet" rotation meaning that no notification is
3415 * emitted and no renaming of the current trace chunk takes
3416 * place.
3417 */
3418 ret = cmd_rotate_session(session, NULL, true,
3419 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION);
3420 /*
3421 * Rotation operations may not be supported by the kernel
3422 * tracer. Hence, do not consider this implicit rotation as
3423 * a session destruction error. The library has already stopped
3424 * the session and waited for pending data; there is nothing
3425 * left to do but complete the destruction of the session.
3426 */
3427 if (ret != LTTNG_OK &&
3428 ret != -LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL) {
3429 ERR("Failed to perform a quiet rotation as part of the destruction of session \"%s\": %s",
3430 session->name, lttng_strerror(ret));
3431 destruction_last_error = -ret;
3432 }
3433 }
3434
3435 if (session->shm_path[0]) {
3436 /*
3437 * When a session is created with an explicit shm_path,
3438 * the consumer daemon will create its shared memory files
3439 * at that location and will *not* unlink them. This is normal
3440 * as the intention of that feature is to make it possible
3441 * to retrieve the content of those files should a crash occur.
3442 *
3443 * To ensure the content of those files can be used, the
3444 * sessiond daemon will replicate the content of the metadata
3445 * cache in a metadata file.
3446 *
3447 * On clean-up, it is expected that the consumer daemon will
3448 * unlink the shared memory files and that the session daemon
3449 * will unlink the metadata file. Then, the session's directory
3450 * in the shm path can be removed.
3451 *
3452 * Unfortunately, a flaw in the design of the sessiond's and
3453 * consumerd's tear down of channels makes it impossible to
3454 * determine when the sessiond _and_ the consumerd have both
3455 * destroyed their representation of a channel. For one, the
3456 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3457 * callbacks in both daemons.
3458 *
3459 * However, it is also impossible for the sessiond to know when
3460 * the consumer daemon is done destroying its channel(s) since
3461 * it occurs as a reaction to the closing of the channel's file
3462 * descriptor. There is no resulting communication initiated
3463 * from the consumerd to the sessiond to confirm that the
3464 * operation is completed (and was successful).
3465 *
3466 * Until this is all fixed, the session daemon checks for the
3467 * removal of the session's shm path which makes it possible
3468 * to safely advertise a session as having been destroyed.
3469 *
3470 * Prior to this fix, it was not possible to reliably save
3471 * a session making use of the --shm-path option, destroy it,
3472 * and load it again. This is because the creation of the
3473 * session would fail upon seeing the session's shm path
3474 * already in existence.
3475 *
3476 * Note that none of the error paths in the check for the
3477 * directory's existence return an error. This is normal
3478 * as there isn't much that can be done. The session will
3479 * be destroyed properly, except that we can't offer the
3480 * guarantee that the same session can be re-created.
3481 */
3482 current_completion_handler = &destroy_completion_handler.handler;
3483 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3484 session->shm_path,
3485 sizeof(destroy_completion_handler.shm_path));
3486 assert(!ret);
3487 }
3488
3489 /*
3490 * The session is destroyed. However, note that the command context
3491 * still holds a reference to the session, thus delaying its destruction
3492 * _at least_ up to the point when that reference is released.
3493 */
3494 session_destroy(session);
3495 if (reply_context) {
3496 reply_context->destruction_status = destruction_last_error;
3497 ret = session_add_destroy_notifier(session,
3498 cmd_destroy_session_reply,
3499 (void *) reply_context);
3500 if (ret) {
3501 ret = LTTNG_ERR_FATAL;
3502 goto end;
3503 } else {
3504 *sock_fd = -1;
3505 }
3506 }
3507 ret = LTTNG_OK;
3508 end:
3509 return ret;
3510 }
3511
3512 /*
3513 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3514 */
3515 int cmd_register_consumer(struct ltt_session *session,
3516 enum lttng_domain_type domain, const char *sock_path,
3517 struct consumer_data *cdata)
3518 {
3519 int ret, sock;
3520 struct consumer_socket *socket = NULL;
3521
3522 assert(session);
3523 assert(cdata);
3524 assert(sock_path);
3525
3526 switch (domain) {
3527 case LTTNG_DOMAIN_KERNEL:
3528 {
3529 struct ltt_kernel_session *ksess = session->kernel_session;
3530
3531 assert(ksess);
3532
3533 /* Can't register a consumer if there is already one */
3534 if (ksess->consumer_fds_sent != 0) {
3535 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3536 goto error;
3537 }
3538
3539 sock = lttcomm_connect_unix_sock(sock_path);
3540 if (sock < 0) {
3541 ret = LTTNG_ERR_CONNECT_FAIL;
3542 goto error;
3543 }
3544 cdata->cmd_sock = sock;
3545
3546 socket = consumer_allocate_socket(&cdata->cmd_sock);
3547 if (socket == NULL) {
3548 ret = close(sock);
3549 if (ret < 0) {
3550 PERROR("close register consumer");
3551 }
3552 cdata->cmd_sock = -1;
3553 ret = LTTNG_ERR_FATAL;
3554 goto error;
3555 }
3556
3557 socket->lock = zmalloc(sizeof(pthread_mutex_t));
3558 if (socket->lock == NULL) {
3559 PERROR("zmalloc pthread mutex");
3560 ret = LTTNG_ERR_FATAL;
3561 goto error;
3562 }
3563 pthread_mutex_init(socket->lock, NULL);
3564 socket->registered = 1;
3565
3566 rcu_read_lock();
3567 consumer_add_socket(socket, ksess->consumer);
3568 rcu_read_unlock();
3569
3570 pthread_mutex_lock(&cdata->pid_mutex);
3571 cdata->pid = -1;
3572 pthread_mutex_unlock(&cdata->pid_mutex);
3573
3574 break;
3575 }
3576 default:
3577 /* TODO: Userspace tracing */
3578 ret = LTTNG_ERR_UND;
3579 goto error;
3580 }
3581
3582 return LTTNG_OK;
3583
3584 error:
3585 if (socket) {
3586 consumer_destroy_socket(socket);
3587 }
3588 return ret;
3589 }
3590
3591 /*
3592 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3593 */
3594 ssize_t cmd_list_domains(struct ltt_session *session,
3595 struct lttng_domain **domains)
3596 {
3597 int ret, index = 0;
3598 ssize_t nb_dom = 0;
3599 struct agent *agt;
3600 struct lttng_ht_iter iter;
3601
3602 if (session->kernel_session != NULL) {
3603 DBG3("Listing domains found kernel domain");
3604 nb_dom++;
3605 }
3606
3607 if (session->ust_session != NULL) {
3608 DBG3("Listing domains found UST global domain");
3609 nb_dom++;
3610
3611 rcu_read_lock();
3612 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3613 agt, node.node) {
3614 if (agt->being_used) {
3615 nb_dom++;
3616 }
3617 }
3618 rcu_read_unlock();
3619 }
3620
3621 if (!nb_dom) {
3622 goto end;
3623 }
3624
3625 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3626 if (*domains == NULL) {
3627 ret = LTTNG_ERR_FATAL;
3628 goto error;
3629 }
3630
3631 if (session->kernel_session != NULL) {
3632 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3633
3634 /* Kernel session buffer type is always GLOBAL */
3635 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3636
3637 index++;
3638 }
3639
3640 if (session->ust_session != NULL) {
3641 (*domains)[index].type = LTTNG_DOMAIN_UST;
3642 (*domains)[index].buf_type = session->ust_session->buffer_type;
3643 index++;
3644
3645 rcu_read_lock();
3646 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3647 agt, node.node) {
3648 if (agt->being_used) {
3649 (*domains)[index].type = agt->domain;
3650 (*domains)[index].buf_type = session->ust_session->buffer_type;
3651 index++;
3652 }
3653 }
3654 rcu_read_unlock();
3655 }
3656 end:
3657 return nb_dom;
3658
3659 error:
3660 /* Return negative value to differentiate return code */
3661 return -ret;
3662 }
3663
3664
3665 /*
3666 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3667 */
3668 ssize_t cmd_list_channels(enum lttng_domain_type domain,
3669 struct ltt_session *session, struct lttng_channel **channels)
3670 {
3671 ssize_t nb_chan = 0, payload_size = 0, ret;
3672
3673 switch (domain) {
3674 case LTTNG_DOMAIN_KERNEL:
3675 if (session->kernel_session != NULL) {
3676 nb_chan = session->kernel_session->channel_count;
3677 }
3678 DBG3("Number of kernel channels %zd", nb_chan);
3679 if (nb_chan <= 0) {
3680 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
3681 goto end;
3682 }
3683 break;
3684 case LTTNG_DOMAIN_UST:
3685 if (session->ust_session != NULL) {
3686 rcu_read_lock();
3687 nb_chan = lttng_ht_get_count(
3688 session->ust_session->domain_global.channels);
3689 rcu_read_unlock();
3690 }
3691 DBG3("Number of UST global channels %zd", nb_chan);
3692 if (nb_chan < 0) {
3693 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
3694 goto end;
3695 }
3696 break;
3697 default:
3698 ret = -LTTNG_ERR_UND;
3699 goto end;
3700 }
3701
3702 if (nb_chan > 0) {
3703 const size_t channel_size = sizeof(struct lttng_channel) +
3704 sizeof(struct lttng_channel_extended);
3705 struct lttng_channel_extended *channel_exts;
3706
3707 payload_size = nb_chan * channel_size;
3708 *channels = zmalloc(payload_size);
3709 if (*channels == NULL) {
3710 ret = -LTTNG_ERR_FATAL;
3711 goto end;
3712 }
3713
3714 channel_exts = ((void *) *channels) +
3715 (nb_chan * sizeof(struct lttng_channel));
3716 ret = list_lttng_channels(domain, session, *channels, channel_exts);
3717 if (ret != LTTNG_OK) {
3718 free(*channels);
3719 *channels = NULL;
3720 goto end;
3721 }
3722 } else {
3723 *channels = NULL;
3724 }
3725
3726 ret = payload_size;
3727 end:
3728 return ret;
3729 }
3730
3731 /*
3732 * Command LTTNG_LIST_EVENTS processed by the client thread.
3733 */
3734 ssize_t cmd_list_events(enum lttng_domain_type domain,
3735 struct ltt_session *session, char *channel_name,
3736 struct lttng_event **events, size_t *total_size)
3737 {
3738 int ret = 0;
3739 ssize_t nb_event = 0;
3740
3741 switch (domain) {
3742 case LTTNG_DOMAIN_KERNEL:
3743 if (session->kernel_session != NULL) {
3744 nb_event = list_lttng_kernel_events(channel_name,
3745 session->kernel_session, events,
3746 total_size);
3747 }
3748 break;
3749 case LTTNG_DOMAIN_UST:
3750 {
3751 if (session->ust_session != NULL) {
3752 nb_event = list_lttng_ust_global_events(channel_name,
3753 &session->ust_session->domain_global, events,
3754 total_size);
3755 }
3756 break;
3757 }
3758 case LTTNG_DOMAIN_LOG4J:
3759 case LTTNG_DOMAIN_JUL:
3760 case LTTNG_DOMAIN_PYTHON:
3761 if (session->ust_session) {
3762 struct lttng_ht_iter iter;
3763 struct agent *agt;
3764
3765 rcu_read_lock();
3766 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3767 &iter.iter, agt, node.node) {
3768 if (agt->domain == domain) {
3769 nb_event = list_lttng_agent_events(
3770 agt, events,
3771 total_size);
3772 break;
3773 }
3774 }
3775 rcu_read_unlock();
3776 }
3777 break;
3778 default:
3779 ret = LTTNG_ERR_UND;
3780 goto error;
3781 }
3782
3783 return nb_event;
3784
3785 error:
3786 /* Return negative value to differentiate return code */
3787 return -ret;
3788 }
3789
3790 /*
3791 * Using the session list, filled a lttng_session array to send back to the
3792 * client for session listing.
3793 *
3794 * The session list lock MUST be acquired before calling this function. Use
3795 * session_lock_list() and session_unlock_list().
3796 */
3797 void cmd_list_lttng_sessions(struct lttng_session *sessions,
3798 size_t session_count, uid_t uid, gid_t gid)
3799 {
3800 int ret;
3801 unsigned int i = 0;
3802 struct ltt_session *session;
3803 struct ltt_session_list *list = session_get_list();
3804 struct lttng_session_extended *extended =
3805 (typeof(extended)) (&sessions[session_count]);
3806
3807 DBG("Getting all available session for UID %d GID %d",
3808 uid, gid);
3809 /*
3810 * Iterate over session list and append data after the control struct in
3811 * the buffer.
3812 */
3813 cds_list_for_each_entry(session, &list->head, list) {
3814 if (!session_get(session)) {
3815 continue;
3816 }
3817 /*
3818 * Only list the sessions the user can control.
3819 */
3820 if (!session_access_ok(session, uid, gid) ||
3821 session->destroyed) {
3822 session_put(session);
3823 continue;
3824 }
3825
3826 struct ltt_kernel_session *ksess = session->kernel_session;
3827 struct ltt_ust_session *usess = session->ust_session;
3828
3829 if (session->consumer->type == CONSUMER_DST_NET ||
3830 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3831 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3832 ret = build_network_session_path(sessions[i].path,
3833 sizeof(sessions[i].path), session);
3834 } else {
3835 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3836 session->consumer->dst.session_root_path);
3837 }
3838 if (ret < 0) {
3839 PERROR("snprintf session path");
3840 session_put(session);
3841 continue;
3842 }
3843
3844 strncpy(sessions[i].name, session->name, NAME_MAX);
3845 sessions[i].name[NAME_MAX - 1] = '\0';
3846 sessions[i].enabled = session->active;
3847 sessions[i].snapshot_mode = session->snapshot_mode;
3848 sessions[i].live_timer_interval = session->live_timer;
3849 extended[i].creation_time.value = (uint64_t) session->creation_time;
3850 extended[i].creation_time.is_set = 1;
3851 i++;
3852 session_put(session);
3853 }
3854 }
3855
3856 /*
3857 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3858 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3859 */
3860 int cmd_data_pending(struct ltt_session *session)
3861 {
3862 int ret;
3863 struct ltt_kernel_session *ksess = session->kernel_session;
3864 struct ltt_ust_session *usess = session->ust_session;
3865
3866 assert(session);
3867
3868 DBG("Data pending for session %s", session->name);
3869
3870 /* Session MUST be stopped to ask for data availability. */
3871 if (session->active) {
3872 ret = LTTNG_ERR_SESSION_STARTED;
3873 goto error;
3874 } else {
3875 /*
3876 * If stopped, just make sure we've started before else the above call
3877 * will always send that there is data pending.
3878 *
3879 * The consumer assumes that when the data pending command is received,
3880 * the trace has been started before or else no output data is written
3881 * by the streams which is a condition for data pending. So, this is
3882 * *VERY* important that we don't ask the consumer before a start
3883 * trace.
3884 */
3885 if (!session->has_been_started) {
3886 ret = 0;
3887 goto error;
3888 }
3889 }
3890
3891 /* A rotation is still pending, we have to wait. */
3892 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
3893 DBG("Rotate still pending for session %s", session->name);
3894 ret = 1;
3895 goto error;
3896 }
3897
3898 if (ksess && ksess->consumer) {
3899 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3900 if (ret == 1) {
3901 /* Data is still being extracted for the kernel. */
3902 goto error;
3903 }
3904 }
3905
3906 if (usess && usess->consumer) {
3907 ret = consumer_is_data_pending(usess->id, usess->consumer);
3908 if (ret == 1) {
3909 /* Data is still being extracted for the kernel. */
3910 goto error;
3911 }
3912 }
3913
3914 /* Data is ready to be read by a viewer */
3915 ret = 0;
3916
3917 error:
3918 return ret;
3919 }
3920
3921 /*
3922 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3923 *
3924 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3925 */
3926 int cmd_snapshot_add_output(struct ltt_session *session,
3927 const struct lttng_snapshot_output *output, uint32_t *id)
3928 {
3929 int ret;
3930 struct snapshot_output *new_output;
3931
3932 assert(session);
3933 assert(output);
3934
3935 DBG("Cmd snapshot add output for session %s", session->name);
3936
3937 /*
3938 * Can't create an output if the session is not set in no-output mode.
3939 */
3940 if (session->output_traces) {
3941 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3942 goto error;
3943 }
3944
3945 if (session->has_non_mmap_channel) {
3946 ret = LTTNG_ERR_SNAPSHOT_UNSUPPORTED;
3947 goto error;
3948 }
3949
3950 /* Only one output is allowed until we have the "tee" feature. */
3951 if (session->snapshot.nb_output == 1) {
3952 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3953 goto error;
3954 }
3955
3956 new_output = snapshot_output_alloc();
3957 if (!new_output) {
3958 ret = LTTNG_ERR_NOMEM;
3959 goto error;
3960 }
3961
3962 ret = snapshot_output_init(session, output->max_size, output->name,
3963 output->ctrl_url, output->data_url, session->consumer, new_output,
3964 &session->snapshot);
3965 if (ret < 0) {
3966 if (ret == -ENOMEM) {
3967 ret = LTTNG_ERR_NOMEM;
3968 } else {
3969 ret = LTTNG_ERR_INVALID;
3970 }
3971 goto free_error;
3972 }
3973
3974 rcu_read_lock();
3975 snapshot_add_output(&session->snapshot, new_output);
3976 if (id) {
3977 *id = new_output->id;
3978 }
3979 rcu_read_unlock();
3980
3981 return LTTNG_OK;
3982
3983 free_error:
3984 snapshot_output_destroy(new_output);
3985 error:
3986 return ret;
3987 }
3988
3989 /*
3990 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3991 *
3992 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3993 */
3994 int cmd_snapshot_del_output(struct ltt_session *session,
3995 const struct lttng_snapshot_output *output)
3996 {
3997 int ret;
3998 struct snapshot_output *sout = NULL;
3999
4000 assert(session);
4001 assert(output);
4002
4003 rcu_read_lock();
4004
4005 /*
4006 * Permission denied to create an output if the session is not
4007 * set in no output mode.
4008 */
4009 if (session->output_traces) {
4010 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4011 goto error;
4012 }
4013
4014 if (output->id) {
4015 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
4016 session->name);
4017 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
4018 } else if (*output->name != '\0') {
4019 DBG("Cmd snapshot del output name %s for session %s", output->name,
4020 session->name);
4021 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
4022 }
4023 if (!sout) {
4024 ret = LTTNG_ERR_INVALID;
4025 goto error;
4026 }
4027
4028 snapshot_delete_output(&session->snapshot, sout);
4029 snapshot_output_destroy(sout);
4030 ret = LTTNG_OK;
4031
4032 error:
4033 rcu_read_unlock();
4034 return ret;
4035 }
4036
4037 /*
4038 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
4039 *
4040 * If no output is available, outputs is untouched and 0 is returned.
4041 *
4042 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
4043 */
4044 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
4045 struct lttng_snapshot_output **outputs)
4046 {
4047 int ret, idx = 0;
4048 struct lttng_snapshot_output *list = NULL;
4049 struct lttng_ht_iter iter;
4050 struct snapshot_output *output;
4051
4052 assert(session);
4053 assert(outputs);
4054
4055 DBG("Cmd snapshot list outputs for session %s", session->name);
4056
4057 /*
4058 * Permission denied to create an output if the session is not
4059 * set in no output mode.
4060 */
4061 if (session->output_traces) {
4062 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4063 goto end;
4064 }
4065
4066 if (session->snapshot.nb_output == 0) {
4067 ret = 0;
4068 goto end;
4069 }
4070
4071 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
4072 if (!list) {
4073 ret = -LTTNG_ERR_NOMEM;
4074 goto end;
4075 }
4076
4077 /* Copy list from session to the new list object. */
4078 rcu_read_lock();
4079 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
4080 output, node.node) {
4081 assert(output->consumer);
4082 list[idx].id = output->id;
4083 list[idx].max_size = output->max_size;
4084 if (lttng_strncpy(list[idx].name, output->name,
4085 sizeof(list[idx].name))) {
4086 ret = -LTTNG_ERR_INVALID;
4087 goto error;
4088 }
4089 if (output->consumer->type == CONSUMER_DST_LOCAL) {
4090 if (lttng_strncpy(list[idx].ctrl_url,
4091 output->consumer->dst.session_root_path,
4092 sizeof(list[idx].ctrl_url))) {
4093 ret = -LTTNG_ERR_INVALID;
4094 goto error;
4095 }
4096 } else {
4097 /* Control URI. */
4098 ret = uri_to_str_url(&output->consumer->dst.net.control,
4099 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
4100 if (ret < 0) {
4101 ret = -LTTNG_ERR_NOMEM;
4102 goto error;
4103 }
4104
4105 /* Data URI. */
4106 ret = uri_to_str_url(&output->consumer->dst.net.data,
4107 list[idx].data_url, sizeof(list[idx].data_url));
4108 if (ret < 0) {
4109 ret = -LTTNG_ERR_NOMEM;
4110 goto error;
4111 }
4112 }
4113 idx++;
4114 }
4115
4116 *outputs = list;
4117 list = NULL;
4118 ret = session->snapshot.nb_output;
4119 error:
4120 rcu_read_unlock();
4121 free(list);
4122 end:
4123 return ret;
4124 }
4125
4126 /*
4127 * Check if we can regenerate the metadata for this session.
4128 * Only kernel, UST per-uid and non-live sessions are supported.
4129 *
4130 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
4131 */
4132 static
4133 int check_regenerate_metadata_support(struct ltt_session *session)
4134 {
4135 int ret;
4136
4137 assert(session);
4138
4139 if (session->live_timer != 0) {
4140 ret = LTTNG_ERR_LIVE_SESSION;
4141 goto end;
4142 }
4143 if (!session->active) {
4144 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4145 goto end;
4146 }
4147 if (session->ust_session) {
4148 switch (session->ust_session->buffer_type) {
4149 case LTTNG_BUFFER_PER_UID:
4150 break;
4151 case LTTNG_BUFFER_PER_PID:
4152 ret = LTTNG_ERR_PER_PID_SESSION;
4153 goto end;
4154 default:
4155 assert(0);
4156 ret = LTTNG_ERR_UNK;
4157 goto end;
4158 }
4159 }
4160 if (session->consumer->type == CONSUMER_DST_NET &&
4161 session->consumer->relay_minor_version < 8) {
4162 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
4163 goto end;
4164 }
4165 ret = 0;
4166
4167 end:
4168 return ret;
4169 }
4170
4171 static
4172 int clear_metadata_file(int fd)
4173 {
4174 int ret;
4175 off_t lseek_ret;
4176
4177 lseek_ret = lseek(fd, 0, SEEK_SET);
4178 if (lseek_ret < 0) {
4179 PERROR("lseek");
4180 ret = -1;
4181 goto end;
4182 }
4183
4184 ret = ftruncate(fd, 0);
4185 if (ret < 0) {
4186 PERROR("ftruncate");
4187 goto end;
4188 }
4189
4190 end:
4191 return ret;
4192 }
4193
4194 static
4195 int ust_regenerate_metadata(struct ltt_ust_session *usess)
4196 {
4197 int ret = 0;
4198 struct buffer_reg_uid *uid_reg = NULL;
4199 struct buffer_reg_session *session_reg = NULL;
4200
4201 rcu_read_lock();
4202 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
4203 struct ust_registry_session *registry;
4204 struct ust_registry_channel *chan;
4205 struct lttng_ht_iter iter_chan;
4206
4207 session_reg = uid_reg->registry;
4208 registry = session_reg->reg.ust;
4209
4210 pthread_mutex_lock(&registry->lock);
4211 registry->metadata_len_sent = 0;
4212 memset(registry->metadata, 0, registry->metadata_alloc_len);
4213 registry->metadata_len = 0;
4214 registry->metadata_version++;
4215 if (registry->metadata_fd > 0) {
4216 /* Clear the metadata file's content. */
4217 ret = clear_metadata_file(registry->metadata_fd);
4218 if (ret) {
4219 pthread_mutex_unlock(&registry->lock);
4220 goto end;
4221 }
4222 }
4223
4224 ret = ust_metadata_session_statedump(registry, NULL,
4225 registry->major, registry->minor);
4226 if (ret) {
4227 pthread_mutex_unlock(&registry->lock);
4228 ERR("Failed to generate session metadata (err = %d)",
4229 ret);
4230 goto end;
4231 }
4232 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
4233 chan, node.node) {
4234 struct ust_registry_event *event;
4235 struct lttng_ht_iter iter_event;
4236
4237 ret = ust_metadata_channel_statedump(registry, chan);
4238 if (ret) {
4239 pthread_mutex_unlock(&registry->lock);
4240 ERR("Failed to generate channel metadata "
4241 "(err = %d)", ret);
4242 goto end;
4243 }
4244 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
4245 event, node.node) {
4246 ret = ust_metadata_event_statedump(registry,
4247 chan, event);
4248 if (ret) {
4249 pthread_mutex_unlock(&registry->lock);
4250 ERR("Failed to generate event metadata "
4251 "(err = %d)", ret);
4252 goto end;
4253 }
4254 }
4255 }
4256 pthread_mutex_unlock(&registry->lock);
4257 }
4258
4259 end:
4260 rcu_read_unlock();
4261 return ret;
4262 }
4263
4264 /*
4265 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
4266 *
4267 * Ask the consumer to truncate the existing metadata file(s) and
4268 * then regenerate the metadata. Live and per-pid sessions are not
4269 * supported and return an error.
4270 *
4271 * Return 0 on success or else a LTTNG_ERR code.
4272 */
4273 int cmd_regenerate_metadata(struct ltt_session *session)
4274 {
4275 int ret;
4276
4277 assert(session);
4278
4279 ret = check_regenerate_metadata_support(session);
4280 if (ret) {
4281 goto end;
4282 }
4283
4284 if (session->kernel_session) {
4285 ret = kernctl_session_regenerate_metadata(
4286 session->kernel_session->fd);
4287 if (ret < 0) {
4288 ERR("Failed to regenerate the kernel metadata");
4289 goto end;
4290 }
4291 }
4292
4293 if (session->ust_session) {
4294 ret = ust_regenerate_metadata(session->ust_session);
4295 if (ret < 0) {
4296 ERR("Failed to regenerate the UST metadata");
4297 goto end;
4298 }
4299 }
4300 DBG("Cmd metadata regenerate for session %s", session->name);
4301 ret = LTTNG_OK;
4302
4303 end:
4304 return ret;
4305 }
4306
4307 /*
4308 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
4309 *
4310 * Ask the tracer to regenerate a new statedump.
4311 *
4312 * Return 0 on success or else a LTTNG_ERR code.
4313 */
4314 int cmd_regenerate_statedump(struct ltt_session *session)
4315 {
4316 int ret;
4317
4318 assert(session);
4319
4320 if (!session->active) {
4321 ret = LTTNG_ERR_SESSION_NOT_STARTED;
4322 goto end;
4323 }
4324
4325 if (session->kernel_session) {
4326 ret = kernctl_session_regenerate_statedump(
4327 session->kernel_session->fd);
4328 /*
4329 * Currently, the statedump in kernel can only fail if out
4330 * of memory.
4331 */
4332 if (ret < 0) {
4333 if (ret == -ENOMEM) {
4334 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
4335 } else {
4336 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4337 }
4338 ERR("Failed to regenerate the kernel statedump");
4339 goto end;
4340 }
4341 }
4342
4343 if (session->ust_session) {
4344 ret = ust_app_regenerate_statedump_all(session->ust_session);
4345 /*
4346 * Currently, the statedump in UST always returns 0.
4347 */
4348 if (ret < 0) {
4349 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
4350 ERR("Failed to regenerate the UST statedump");
4351 goto end;
4352 }
4353 }
4354 DBG("Cmd regenerate statedump for session %s", session->name);
4355 ret = LTTNG_OK;
4356
4357 end:
4358 return ret;
4359 }
4360
4361 int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
4362 struct notification_thread_handle *notification_thread)
4363 {
4364 int ret;
4365 size_t trigger_len;
4366 ssize_t sock_recv_len;
4367 struct lttng_trigger *trigger = NULL;
4368 struct lttng_buffer_view view;
4369 struct lttng_dynamic_buffer trigger_buffer;
4370
4371 lttng_dynamic_buffer_init(&trigger_buffer);
4372 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4373 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4374 if (ret) {
4375 ret = LTTNG_ERR_NOMEM;
4376 goto end;
4377 }
4378
4379 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4380 trigger_len);
4381 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4382 ERR("Failed to receive \"register trigger\" command payload");
4383 /* TODO: should this be a new error enum ? */
4384 ret = LTTNG_ERR_INVALID_TRIGGER;
4385 goto end;
4386 }
4387
4388 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4389 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4390 trigger_len) {
4391 ERR("Invalid trigger payload received in \"register trigger\" command");
4392 ret = LTTNG_ERR_INVALID_TRIGGER;
4393 goto end;
4394 }
4395
4396 ret = notification_thread_command_register_trigger(notification_thread,
4397 trigger);
4398 /* Ownership of trigger was transferred. */
4399 trigger = NULL;
4400 end:
4401 lttng_trigger_destroy(trigger);
4402 lttng_dynamic_buffer_reset(&trigger_buffer);
4403 return ret;
4404 }
4405
4406 int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
4407 struct notification_thread_handle *notification_thread)
4408 {
4409 int ret;
4410 size_t trigger_len;
4411 ssize_t sock_recv_len;
4412 struct lttng_trigger *trigger = NULL;
4413 struct lttng_buffer_view view;
4414 struct lttng_dynamic_buffer trigger_buffer;
4415
4416 lttng_dynamic_buffer_init(&trigger_buffer);
4417 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4418 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4419 if (ret) {
4420 ret = LTTNG_ERR_NOMEM;
4421 goto end;
4422 }
4423
4424 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4425 trigger_len);
4426 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4427 ERR("Failed to receive \"unregister trigger\" command payload");
4428 /* TODO: should this be a new error enum ? */
4429 ret = LTTNG_ERR_INVALID_TRIGGER;
4430 goto end;
4431 }
4432
4433 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4434 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4435 trigger_len) {
4436 ERR("Invalid trigger payload received in \"unregister trigger\" command");
4437 ret = LTTNG_ERR_INVALID_TRIGGER;
4438 goto end;
4439 }
4440
4441 ret = notification_thread_command_unregister_trigger(notification_thread,
4442 trigger);
4443 end:
4444 lttng_trigger_destroy(trigger);
4445 lttng_dynamic_buffer_reset(&trigger_buffer);
4446 return ret;
4447 }
4448
4449 /*
4450 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4451 * snapshot output is *not* set with a remote destination.
4452 *
4453 * Return LTTNG_OK on success or a LTTNG_ERR code.
4454 */
4455 static enum lttng_error_code set_relayd_for_snapshot(
4456 struct consumer_output *output,
4457 const struct ltt_session *session)
4458 {
4459 enum lttng_error_code status = LTTNG_OK;
4460 struct lttng_ht_iter iter;
4461 struct consumer_socket *socket;
4462 LTTNG_OPTIONAL(uint64_t) current_chunk_id = {};
4463 const char *base_path;
4464
4465 assert(output);
4466 assert(session);
4467
4468 DBG2("Set relayd object from snapshot output");
4469
4470 if (session->current_trace_chunk) {
4471 enum lttng_trace_chunk_status chunk_status =
4472 lttng_trace_chunk_get_id(
4473 session->current_trace_chunk,
4474 &current_chunk_id.value);
4475
4476 if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK) {
4477 current_chunk_id.is_set = true;
4478 } else {
4479 ERR("Failed to get current trace chunk id");
4480 status = LTTNG_ERR_UNK;
4481 goto error;
4482 }
4483 }
4484
4485 /* Ignore if snapshot consumer output is not network. */
4486 if (output->type != CONSUMER_DST_NET) {
4487 goto error;
4488 }
4489
4490 /*
4491 * The snapshot record URI base path overrides the session
4492 * base path.
4493 */
4494 if (output->dst.net.control.subdir[0] != '\0') {
4495 base_path = output->dst.net.control.subdir;
4496 } else {
4497 base_path = session->base_path;
4498 }
4499
4500 /*
4501 * For each consumer socket, create and send the relayd object of the
4502 * snapshot output.
4503 */
4504 rcu_read_lock();
4505 cds_lfht_for_each_entry(output->socks->ht, &iter.iter,
4506 socket, node.node) {
4507 pthread_mutex_lock(socket->lock);
4508 status = send_consumer_relayd_sockets(0, session->id,
4509 output, socket,
4510 session->name, session->hostname,
4511 base_path,
4512 session->live_timer,
4513 current_chunk_id.is_set ? &current_chunk_id.value : NULL,
4514 session->creation_time,
4515 session->name_contains_creation_time);
4516 pthread_mutex_unlock(socket->lock);
4517 if (status != LTTNG_OK) {
4518 rcu_read_unlock();
4519 goto error;
4520 }
4521 }
4522 rcu_read_unlock();
4523
4524 error:
4525 return status;
4526 }
4527
4528 /*
4529 * Record a kernel snapshot.
4530 *
4531 * Return LTTNG_OK on success or a LTTNG_ERR code.
4532 */
4533 static enum lttng_error_code record_kernel_snapshot(
4534 struct ltt_kernel_session *ksess,
4535 const struct consumer_output *output,
4536 const struct ltt_session *session,
4537 int wait, uint64_t nb_packets_per_stream)
4538 {
4539 enum lttng_error_code status;
4540
4541 assert(ksess);
4542 assert(output);
4543 assert(session);
4544
4545 status = kernel_snapshot_record(
4546 ksess, output, wait, nb_packets_per_stream);
4547 return status;
4548 }
4549
4550 /*
4551 * Record a UST snapshot.
4552 *
4553 * Returns LTTNG_OK on success or a LTTNG_ERR error code.
4554 */
4555 static enum lttng_error_code record_ust_snapshot(struct ltt_ust_session *usess,
4556 const struct consumer_output *output,
4557 const struct ltt_session *session,
4558 int wait, uint64_t nb_packets_per_stream)
4559 {
4560 enum lttng_error_code status;
4561
4562 assert(usess);
4563 assert(output);
4564 assert(session);
4565
4566 status = ust_app_snapshot_record(
4567 usess, output, wait, nb_packets_per_stream);
4568 return status;
4569 }
4570
4571 static
4572 uint64_t get_session_size_one_more_packet_per_stream(
4573 const struct ltt_session *session, uint64_t cur_nr_packets)
4574 {
4575 uint64_t tot_size = 0;
4576
4577 if (session->kernel_session) {
4578 struct ltt_kernel_channel *chan;
4579 const struct ltt_kernel_session *ksess =
4580 session->kernel_session;
4581
4582 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
4583 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
4584 /*
4585 * Don't take channel into account if we
4586 * already grab all its packets.
4587 */
4588 continue;
4589 }
4590 tot_size += chan->channel->attr.subbuf_size
4591 * chan->stream_count;
4592 }
4593 }
4594
4595 if (session->ust_session) {
4596 const struct ltt_ust_session *usess = session->ust_session;
4597
4598 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
4599 cur_nr_packets);
4600 }
4601
4602 return tot_size;
4603 }
4604
4605 /*
4606 * Calculate the number of packets we can grab from each stream that
4607 * fits within the overall snapshot max size.
4608 *
4609 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
4610 * the number of packets per stream.
4611 *
4612 * TODO: this approach is not perfect: we consider the worse case
4613 * (packet filling the sub-buffers) as an upper bound, but we could do
4614 * better if we do this calculation while we actually grab the packet
4615 * content: we would know how much padding we don't actually store into
4616 * the file.
4617 *
4618 * This algorithm is currently bounded by the number of packets per
4619 * stream.
4620 *
4621 * Since we call this algorithm before actually grabbing the data, it's
4622 * an approximation: for instance, applications could appear/disappear
4623 * in between this call and actually grabbing data.
4624 */
4625 static
4626 int64_t get_session_nb_packets_per_stream(const struct ltt_session *session,
4627 uint64_t max_size)
4628 {
4629 int64_t size_left;
4630 uint64_t cur_nb_packets = 0;
4631
4632 if (!max_size) {
4633 return 0; /* Infinite */
4634 }
4635
4636 size_left = max_size;
4637 for (;;) {
4638 uint64_t one_more_packet_tot_size;
4639
4640 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(
4641 session, cur_nb_packets);
4642 if (!one_more_packet_tot_size) {
4643 /* We are already grabbing all packets. */
4644 break;
4645 }
4646 size_left -= one_more_packet_tot_size;
4647 if (size_left < 0) {
4648 break;
4649 }
4650 cur_nb_packets++;
4651 }
4652 if (!cur_nb_packets && size_left != max_size) {
4653 /* Not enough room to grab one packet of each stream, error. */
4654 return -1;
4655 }
4656 return cur_nb_packets;
4657 }
4658
4659 static
4660 enum lttng_error_code snapshot_record(struct ltt_session *session,
4661 const struct snapshot_output *snapshot_output, int wait)
4662 {
4663 int64_t nb_packets_per_stream;
4664 char snapshot_chunk_name[LTTNG_NAME_MAX];
4665 int ret;
4666 enum lttng_error_code ret_code = LTTNG_OK;
4667 struct lttng_trace_chunk *snapshot_trace_chunk;
4668 struct consumer_output *original_ust_consumer_output = NULL;
4669 struct consumer_output *original_kernel_consumer_output = NULL;
4670 struct consumer_output *snapshot_ust_consumer_output = NULL;
4671 struct consumer_output *snapshot_kernel_consumer_output = NULL;
4672
4673 ret = snprintf(snapshot_chunk_name, sizeof(snapshot_chunk_name),
4674 "%s-%s-%" PRIu64,
4675 snapshot_output->name,
4676 snapshot_output->datetime,
4677 snapshot_output->nb_snapshot);
4678 if (ret < 0 || ret >= sizeof(snapshot_chunk_name)) {
4679 ERR("Failed to format snapshot name");
4680 ret_code = LTTNG_ERR_INVALID;
4681 goto error;
4682 }
4683 DBG("Recording snapshot \"%s\" for session \"%s\" with chunk name \"%s\"",
4684 snapshot_output->name, session->name,
4685 snapshot_chunk_name);
4686 if (!session->kernel_session && !session->ust_session) {
4687 ERR("Failed to record snapshot as no channels exist");
4688 ret_code = LTTNG_ERR_NO_CHANNEL;
4689 goto error;
4690 }
4691
4692 if (session->kernel_session) {
4693 original_kernel_consumer_output =
4694 session->kernel_session->consumer;
4695 snapshot_kernel_consumer_output =
4696 consumer_copy_output(snapshot_output->consumer);
4697 strcpy(snapshot_kernel_consumer_output->chunk_path,
4698 snapshot_chunk_name);
4699
4700 /* Copy the original domain subdir. */
4701 strcpy(snapshot_kernel_consumer_output->domain_subdir,
4702 original_kernel_consumer_output->domain_subdir);
4703
4704 ret = consumer_copy_sockets(snapshot_kernel_consumer_output,
4705 original_kernel_consumer_output);
4706 if (ret < 0) {
4707 ERR("Failed to copy consumer sockets from snapshot output configuration");
4708 ret_code = LTTNG_ERR_NOMEM;
4709 goto error;
4710 }
4711 ret_code = set_relayd_for_snapshot(
4712 snapshot_kernel_consumer_output, session);
4713 if (ret_code != LTTNG_OK) {
4714 ERR("Failed to setup relay daemon for kernel tracer snapshot");
4715 goto error;
4716 }
4717 session->kernel_session->consumer =
4718 snapshot_kernel_consumer_output;
4719 }
4720 if (session->ust_session) {
4721 original_ust_consumer_output = session->ust_session->consumer;
4722 snapshot_ust_consumer_output =
4723 consumer_copy_output(snapshot_output->consumer);
4724 strcpy(snapshot_ust_consumer_output->chunk_path,
4725 snapshot_chunk_name);
4726
4727 /* Copy the original domain subdir. */
4728 strcpy(snapshot_ust_consumer_output->domain_subdir,
4729 original_ust_consumer_output->domain_subdir);
4730
4731 ret = consumer_copy_sockets(snapshot_ust_consumer_output,
4732 original_ust_consumer_output);
4733 if (ret < 0) {
4734 ERR("Failed to copy consumer sockets from snapshot output configuration");
4735 ret_code = LTTNG_ERR_NOMEM;
4736 goto error;
4737 }
4738 ret_code = set_relayd_for_snapshot(
4739 snapshot_ust_consumer_output, session);
4740 if (ret_code != LTTNG_OK) {
4741 ERR("Failed to setup relay daemon for userspace tracer snapshot");
4742 goto error;
4743 }
4744 session->ust_session->consumer =
4745 snapshot_ust_consumer_output;
4746 }
4747
4748 snapshot_trace_chunk = session_create_new_trace_chunk(session,
4749 snapshot_kernel_consumer_output ?:
4750 snapshot_ust_consumer_output,
4751 consumer_output_get_base_path(
4752 snapshot_output->consumer),
4753 snapshot_chunk_name);
4754 if (!snapshot_trace_chunk) {
4755 ERR("Failed to create temporary trace chunk to record a snapshot of session \"%s\"",
4756 session->name);
4757 ret_code = LTTNG_ERR_CREATE_DIR_FAIL;
4758 goto error;
4759 }
4760 assert(!session->current_trace_chunk);
4761 ret = session_set_trace_chunk(session, snapshot_trace_chunk, NULL);
4762 lttng_trace_chunk_put(snapshot_trace_chunk);
4763 snapshot_trace_chunk = NULL;
4764 if (ret) {
4765 ERR("Failed to set temporary trace chunk to record a snapshot of session \"%s\"",
4766 session->name);
4767 ret_code = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
4768 goto error;
4769 }
4770
4771 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
4772 snapshot_output->max_size);
4773 if (nb_packets_per_stream < 0) {
4774 ret_code = LTTNG_ERR_MAX_SIZE_INVALID;
4775 goto error_close_trace_chunk;
4776 }
4777
4778 if (session->kernel_session) {
4779 ret_code = record_kernel_snapshot(session->kernel_session,
4780 snapshot_kernel_consumer_output, session,
4781 wait, nb_packets_per_stream);
4782 if (ret_code != LTTNG_OK) {
4783 goto error_close_trace_chunk;
4784 }
4785 }
4786
4787 if (session->ust_session) {
4788 ret_code = record_ust_snapshot(session->ust_session,
4789 snapshot_ust_consumer_output, session,
4790 wait, nb_packets_per_stream);
4791 if (ret_code != LTTNG_OK) {
4792 goto error_close_trace_chunk;
4793 }
4794 }
4795
4796 error_close_trace_chunk:
4797 if (session_set_trace_chunk(session, NULL, &snapshot_trace_chunk)) {
4798 ERR("Failed to release the current trace chunk of session \"%s\"",
4799 session->name);
4800 ret_code = LTTNG_ERR_UNK;
4801 }
4802
4803 if (session_close_trace_chunk(session, snapshot_trace_chunk,
4804 LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION, NULL)) {
4805 /*
4806 * Don't goto end; make sure the chunk is closed for the session
4807 * to allow future snapshots.
4808 */
4809 ERR("Failed to close snapshot trace chunk of session \"%s\"",
4810 session->name);
4811 ret_code = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
4812 }
4813
4814 lttng_trace_chunk_put(snapshot_trace_chunk);
4815 snapshot_trace_chunk = NULL;
4816 error:
4817 if (original_ust_consumer_output) {
4818 session->ust_session->consumer = original_ust_consumer_output;
4819 }
4820 if (original_kernel_consumer_output) {
4821 session->kernel_session->consumer =
4822 original_kernel_consumer_output;
4823 }
4824 consumer_output_put(snapshot_ust_consumer_output);
4825 consumer_output_put(snapshot_kernel_consumer_output);
4826 return ret_code;
4827 }
4828
4829 /*
4830 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
4831 *
4832 * The wait parameter is ignored so this call always wait for the snapshot to
4833 * complete before returning.
4834 *
4835 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4836 */
4837 int cmd_snapshot_record(struct ltt_session *session,
4838 const struct lttng_snapshot_output *output, int wait)
4839 {
4840 enum lttng_error_code cmd_ret = LTTNG_OK;
4841 int ret;
4842 unsigned int snapshot_success = 0;
4843 char datetime[16];
4844 struct snapshot_output *tmp_output = NULL;
4845
4846 assert(session);
4847 assert(output);
4848
4849 DBG("Cmd snapshot record for session %s", session->name);
4850
4851 /* Get the datetime for the snapshot output directory. */
4852 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
4853 sizeof(datetime));
4854 if (!ret) {
4855 cmd_ret = LTTNG_ERR_INVALID;
4856 goto error;
4857 }
4858
4859 /*
4860 * Permission denied to create an output if the session is not
4861 * set in no output mode.
4862 */
4863 if (session->output_traces) {
4864 cmd_ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4865 goto error;
4866 }
4867
4868 /* The session needs to be started at least once. */
4869 if (!session->has_been_started) {
4870 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
4871 goto error;
4872 }
4873
4874 /* Use temporary output for the session. */
4875 if (*output->ctrl_url != '\0') {
4876 tmp_output = snapshot_output_alloc();
4877 if (!tmp_output) {
4878 cmd_ret = LTTNG_ERR_NOMEM;
4879 goto error;
4880 }
4881
4882 ret = snapshot_output_init(session, output->max_size,
4883 output->name,
4884 output->ctrl_url, output->data_url,
4885 session->consumer,
4886 tmp_output, NULL);
4887 if (ret < 0) {
4888 if (ret == -ENOMEM) {
4889 cmd_ret = LTTNG_ERR_NOMEM;
4890 } else {
4891 cmd_ret = LTTNG_ERR_INVALID;
4892 }
4893 goto error;
4894 }
4895 /* Use the global session count for the temporary snapshot. */
4896 tmp_output->nb_snapshot = session->snapshot.nb_snapshot;
4897
4898 /* Use the global datetime */
4899 memcpy(tmp_output->datetime, datetime, sizeof(datetime));
4900 cmd_ret = snapshot_record(session, tmp_output, wait);
4901 if (cmd_ret != LTTNG_OK) {
4902 goto error;
4903 }
4904 snapshot_success = 1;
4905 } else {
4906 struct snapshot_output *sout;
4907 struct lttng_ht_iter iter;
4908
4909 rcu_read_lock();
4910 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
4911 &iter.iter, sout, node.node) {
4912 struct snapshot_output output_copy;
4913
4914 /*
4915 * Make a local copy of the output and override output
4916 * parameters with those provided as part of the
4917 * command.
4918 */
4919 memcpy(&output_copy, sout, sizeof(output_copy));
4920
4921 if (output->max_size != (uint64_t) -1ULL) {
4922 output_copy.max_size = output->max_size;
4923 }
4924
4925 output_copy.nb_snapshot = session->snapshot.nb_snapshot;
4926 memcpy(output_copy.datetime, datetime,
4927 sizeof(datetime));
4928
4929 /* Use temporary name. */
4930 if (*output->name != '\0') {
4931 if (lttng_strncpy(output_copy.name,
4932 output->name,
4933 sizeof(output_copy.name))) {
4934 cmd_ret = LTTNG_ERR_INVALID;
4935 rcu_read_unlock();
4936 goto error;
4937 }
4938 }
4939
4940 cmd_ret = snapshot_record(session, &output_copy, wait);
4941 if (cmd_ret != LTTNG_OK) {
4942 rcu_read_unlock();
4943 goto error;
4944 }
4945 snapshot_success = 1;
4946 }
4947 rcu_read_unlock();
4948 }
4949
4950 if (snapshot_success) {
4951 session->snapshot.nb_snapshot++;
4952 } else {
4953 cmd_ret = LTTNG_ERR_SNAPSHOT_FAIL;
4954 }
4955
4956 error:
4957 if (tmp_output) {
4958 snapshot_output_destroy(tmp_output);
4959 }
4960 return cmd_ret;
4961 }
4962
4963 /*
4964 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
4965 */
4966 int cmd_set_session_shm_path(struct ltt_session *session,
4967 const char *shm_path)
4968 {
4969 /* Safety net */
4970 assert(session);
4971
4972 /*
4973 * Can only set shm path before session is started.
4974 */
4975 if (session->has_been_started) {
4976 return LTTNG_ERR_SESSION_STARTED;
4977 }
4978
4979 strncpy(session->shm_path, shm_path,
4980 sizeof(session->shm_path));
4981 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
4982
4983 return 0;
4984 }
4985
4986 /*
4987 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
4988 *
4989 * Ask the consumer to rotate the session output directory.
4990 * The session lock must be held.
4991 *
4992 * Returns LTTNG_OK on success or else a negative LTTng error code.
4993 */
4994 int cmd_rotate_session(struct ltt_session *session,
4995 struct lttng_rotate_session_return *rotate_return,
4996 bool quiet_rotation,
4997 enum lttng_trace_chunk_command_type command)
4998 {
4999 int ret;
5000 uint64_t ongoing_rotation_chunk_id;
5001 enum lttng_error_code cmd_ret = LTTNG_OK;
5002 struct lttng_trace_chunk *chunk_being_archived = NULL;
5003 struct lttng_trace_chunk *new_trace_chunk = NULL;
5004 enum lttng_trace_chunk_status chunk_status;
5005 bool failed_to_rotate = false;
5006 enum lttng_error_code rotation_fail_code = LTTNG_OK;
5007
5008 assert(session);
5009
5010 if (!session->has_been_started) {
5011 cmd_ret = LTTNG_ERR_START_SESSION_ONCE;
5012 goto end;
5013 }
5014
5015 /*
5016 * Explicit rotation is not supported for live sessions.
5017 * However, live sessions can perform a quiet rotation on
5018 * destroy.
5019 * Rotation is not supported for snapshot traces (no output).
5020 */
5021 if ((!quiet_rotation && session->live_timer) ||
5022 !session->output_traces) {
5023 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5024 goto end;
5025 }
5026
5027 /* Unsupported feature in lttng-relayd before 2.11. */
5028 if (!quiet_rotation && session->consumer->type == CONSUMER_DST_NET &&
5029 (session->consumer->relay_major_version == 2 &&
5030 session->consumer->relay_minor_version < 11)) {
5031 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
5032 goto end;
5033 }
5034
5035 /* Unsupported feature in lttng-modules before 2.8 (lack of sequence number). */
5036 if (session->kernel_session && !kernel_supports_ring_buffer_packet_sequence_number()) {
5037 cmd_ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE_KERNEL;
5038 goto end;
5039 }
5040
5041 if (session->rotation_state == LTTNG_ROTATION_STATE_ONGOING) {
5042 DBG("Refusing to launch a rotation; a rotation is already in progress for session %s",
5043 session->name);
5044 cmd_ret = LTTNG_ERR_ROTATION_PENDING;
5045 goto end;
5046 }
5047
5048 /*
5049 * After a stop, we only allow one rotation to occur, the other ones are
5050 * useless until a new start.
5051 */
5052 if (session->rotated_after_last_stop) {
5053 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
5054 session->name);
5055 cmd_ret = LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
5056 goto end;
5057 }
5058
5059 /*
5060 * After a stop followed by a clear, disallow following rotations a they would
5061 * generate empty chunks.
5062 */
5063 if (session->cleared_after_last_stop) {
5064 DBG("Session \"%s\" was already cleared after stop, refusing rotation",
5065 session->name);
5066 cmd_ret = LTTNG_ERR_ROTATION_AFTER_STOP_CLEAR;
5067 goto end;
5068 }
5069
5070 if (session->active) {
5071 new_trace_chunk = session_create_new_trace_chunk(session, NULL,
5072 NULL, NULL);
5073 if (!new_trace_chunk) {
5074 cmd_ret = LTTNG_ERR_CREATE_DIR_FAIL;
5075 goto error;
5076 }
5077 }
5078
5079 /*
5080 * The current trace chunk becomes the chunk being archived.
5081 *
5082 * After this point, "chunk_being_archived" must absolutely
5083 * be closed on the consumer(s), otherwise it will never be
5084 * cleaned-up, which will result in a leak.
5085 */
5086 ret = session_set_trace_chunk(session, new_trace_chunk,
5087 &chunk_being_archived);
5088 if (ret) {
5089 cmd_ret = LTTNG_ERR_CREATE_TRACE_CHUNK_FAIL_CONSUMER;
5090 goto error;
5091 }
5092
5093 if (session->kernel_session) {
5094 cmd_ret = kernel_rotate_session(session);
5095 if (cmd_ret != LTTNG_OK) {
5096 failed_to_rotate = true;
5097 rotation_fail_code = cmd_ret;
5098 }
5099 }
5100 if (session->ust_session) {
5101 cmd_ret = ust_app_rotate_session(session);
5102 if (cmd_ret != LTTNG_OK) {
5103 failed_to_rotate = true;
5104 rotation_fail_code = cmd_ret;
5105 }
5106 }
5107
5108 if (!session->active) {
5109 session->rotated_after_last_stop = true;
5110 }
5111
5112 if (!chunk_being_archived) {
5113 DBG("Rotating session \"%s\" from a \"NULL\" trace chunk to a new trace chunk, skipping completion check",
5114 session->name);
5115 if (failed_to_rotate) {
5116 cmd_ret = rotation_fail_code;
5117 goto error;
5118 }
5119 cmd_ret = LTTNG_OK;
5120 goto end;
5121 }
5122
5123 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
5124 chunk_status = lttng_trace_chunk_get_id(chunk_being_archived,
5125 &ongoing_rotation_chunk_id);
5126 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5127
5128 ret = session_close_trace_chunk(session, chunk_being_archived,
5129 command, session->last_chunk_path);
5130 if (ret) {
5131 cmd_ret = LTTNG_ERR_CLOSE_TRACE_CHUNK_FAIL_CONSUMER;
5132 goto error;
5133 }
5134
5135 if (failed_to_rotate) {
5136 cmd_ret = rotation_fail_code;
5137 goto error;
5138 }
5139
5140 session->quiet_rotation = quiet_rotation;
5141 ret = timer_session_rotation_pending_check_start(session,
5142 DEFAULT_ROTATE_PENDING_TIMER);
5143 if (ret) {
5144 cmd_ret = LTTNG_ERR_UNK;
5145 goto error;
5146 }
5147
5148 if (rotate_return) {
5149 rotate_return->rotation_id = ongoing_rotation_chunk_id;
5150 }
5151
5152 session->chunk_being_archived = chunk_being_archived;
5153 chunk_being_archived = NULL;
5154 if (!quiet_rotation) {
5155 ret = notification_thread_command_session_rotation_ongoing(
5156 notification_thread_handle,
5157 session->name, session->uid, session->gid,
5158 ongoing_rotation_chunk_id);
5159 if (ret != LTTNG_OK) {
5160 ERR("Failed to notify notification thread that a session rotation is ongoing for session %s",
5161 session->name);
5162 cmd_ret = ret;
5163 }
5164 }
5165
5166 DBG("Cmd rotate session %s, archive_id %" PRIu64 " sent",
5167 session->name, ongoing_rotation_chunk_id);
5168 end:
5169 lttng_trace_chunk_put(new_trace_chunk);
5170 lttng_trace_chunk_put(chunk_being_archived);
5171 ret = (cmd_ret == LTTNG_OK) ? cmd_ret : -((int) cmd_ret);
5172 return ret;
5173 error:
5174 if (session_reset_rotation_state(session,
5175 LTTNG_ROTATION_STATE_ERROR)) {
5176 ERR("Failed to reset rotation state of session \"%s\"",
5177 session->name);
5178 }
5179 goto end;
5180 }
5181
5182 /*
5183 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
5184 *
5185 * Check if the session has finished its rotation.
5186 *
5187 * Return LTTNG_OK on success or else an LTTNG_ERR code.
5188 */
5189 int cmd_rotate_get_info(struct ltt_session *session,
5190 struct lttng_rotation_get_info_return *info_return,
5191 uint64_t rotation_id)
5192 {
5193 enum lttng_error_code cmd_ret = LTTNG_OK;
5194 enum lttng_rotation_state rotation_state;
5195
5196 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
5197 session->most_recent_chunk_id.value);
5198
5199 if (session->chunk_being_archived) {
5200 enum lttng_trace_chunk_status chunk_status;
5201 uint64_t chunk_id;
5202
5203 chunk_status = lttng_trace_chunk_get_id(
5204 session->chunk_being_archived,
5205 &chunk_id);
5206 assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK);
5207
5208 rotation_state = rotation_id == chunk_id ?
5209 LTTNG_ROTATION_STATE_ONGOING :
5210 LTTNG_ROTATION_STATE_EXPIRED;
5211 } else {
5212 if (session->last_archived_chunk_id.is_set &&
5213 rotation_id != session->last_archived_chunk_id.value) {
5214 rotation_state = LTTNG_ROTATION_STATE_EXPIRED;
5215 } else {
5216 rotation_state = session->rotation_state;
5217 }
5218 }
5219
5220 switch (rotation_state) {
5221 case LTTNG_ROTATION_STATE_NO_ROTATION:
5222 DBG("Reporting that no rotation has occurred within the lifetime of session \"%s\"",
5223 session->name);
5224 goto end;
5225 case LTTNG_ROTATION_STATE_EXPIRED:
5226 DBG("Reporting that the rotation state of rotation id %" PRIu64 " of session \"%s\" has expired",
5227 rotation_id, session->name);
5228 break;
5229 case LTTNG_ROTATION_STATE_ONGOING:
5230 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is still pending",
5231 rotation_id, session->name);
5232 break;
5233 case LTTNG_ROTATION_STATE_COMPLETED:
5234 {
5235 int fmt_ret;
5236 char *chunk_path;
5237 char *current_tracing_path_reply;
5238 size_t current_tracing_path_reply_len;
5239
5240 DBG("Reporting that rotation id %" PRIu64 " of session \"%s\" is completed",
5241 rotation_id, session->name);
5242
5243 switch (session_get_consumer_destination_type(session)) {
5244 case CONSUMER_DST_LOCAL:
5245 current_tracing_path_reply =
5246 info_return->location.local.absolute_path;
5247 current_tracing_path_reply_len =
5248 sizeof(info_return->location.local.absolute_path);
5249 info_return->location_type =
5250 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
5251 fmt_ret = asprintf(&chunk_path,
5252 "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s",
5253 session_get_base_path(session),
5254 session->last_archived_chunk_name);
5255 if (fmt_ret == -1) {
5256 PERROR("Failed to format the path of the last archived trace chunk");
5257 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5258 cmd_ret = LTTNG_ERR_UNK;
5259 goto end;
5260 }
5261 break;
5262 case CONSUMER_DST_NET:
5263 {
5264 uint16_t ctrl_port, data_port;
5265
5266 current_tracing_path_reply =
5267 info_return->location.relay.relative_path;
5268 current_tracing_path_reply_len =
5269 sizeof(info_return->location.relay.relative_path);
5270 /* Currently the only supported relay protocol. */
5271 info_return->location.relay.protocol =
5272 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
5273
5274 fmt_ret = lttng_strncpy(info_return->location.relay.host,
5275 session_get_net_consumer_hostname(session),
5276 sizeof(info_return->location.relay.host));
5277 if (fmt_ret) {
5278 ERR("Failed to copy host name to rotate_get_info reply");
5279 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5280 cmd_ret = LTTNG_ERR_SET_URL;
5281 goto end;
5282 }
5283
5284 session_get_net_consumer_ports(session, &ctrl_port, &data_port);
5285 info_return->location.relay.ports.control = ctrl_port;
5286 info_return->location.relay.ports.data = data_port;
5287 info_return->location_type =
5288 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
5289 chunk_path = strdup(session->last_chunk_path);
5290 if (!chunk_path) {
5291 ERR("Failed to allocate the path of the last archived trace chunk");
5292 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5293 cmd_ret = LTTNG_ERR_UNK;
5294 goto end;
5295 }
5296 break;
5297 }
5298 default:
5299 abort();
5300 }
5301
5302 fmt_ret = lttng_strncpy(current_tracing_path_reply,
5303 chunk_path, current_tracing_path_reply_len);
5304 free(chunk_path);
5305 if (fmt_ret) {
5306 ERR("Failed to copy path of the last archived trace chunk to rotate_get_info reply");
5307 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
5308 cmd_ret = LTTNG_ERR_UNK;
5309 goto end;
5310 }
5311
5312 break;
5313 }
5314 case LTTNG_ROTATION_STATE_ERROR:
5315 DBG("Reporting that an error occurred during rotation %" PRIu64 " of session \"%s\"",
5316 rotation_id, session->name);
5317 break;
5318 default:
5319 abort();
5320 }
5321
5322 cmd_ret = LTTNG_OK;
5323 end:
5324 info_return->status = (int32_t) rotation_state;
5325 return cmd_ret;
5326 }
5327
5328 /*
5329 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
5330 *
5331 * Configure the automatic rotation parameters.
5332 * 'activate' to true means activate the rotation schedule type with 'new_value'.
5333 * 'activate' to false means deactivate the rotation schedule and validate that
5334 * 'new_value' has the same value as the currently active value.
5335 *
5336 * Return 0 on success or else a positive LTTNG_ERR code.
5337 */
5338 int cmd_rotation_set_schedule(struct ltt_session *session,
5339 bool activate, enum lttng_rotation_schedule_type schedule_type,
5340 uint64_t new_value,
5341 struct notification_thread_handle *notification_thread_handle)
5342 {
5343 int ret;
5344 uint64_t *parameter_value;
5345
5346 assert(session);
5347
5348 DBG("Cmd rotate set schedule session %s", session->name);
5349
5350 if (session->live_timer || !session->output_traces) {
5351 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
5352 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
5353 goto end;
5354 }
5355
5356 switch (schedule_type) {
5357 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5358 parameter_value = &session->rotate_size;
5359 break;
5360 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5361 parameter_value = &session->rotate_timer_period;
5362 if (new_value >= UINT_MAX) {
5363 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
5364 new_value, UINT_MAX);
5365 ret = LTTNG_ERR_INVALID;
5366 goto end;
5367 }
5368 break;
5369 default:
5370 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
5371 ret = LTTNG_ERR_INVALID;
5372 goto end;
5373 }
5374
5375 /* Improper use of the API. */
5376 if (new_value == -1ULL) {
5377 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
5378 ret = LTTNG_ERR_INVALID;
5379 goto end;
5380 }
5381
5382 /*
5383 * As indicated in struct ltt_session's comments, a value of == 0 means
5384 * this schedule rotation type is not in use.
5385 *
5386 * Reject the command if we were asked to activate a schedule that was
5387 * already active.
5388 */
5389 if (activate && *parameter_value != 0) {
5390 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
5391 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
5392 goto end;
5393 }
5394
5395 /*
5396 * Reject the command if we were asked to deactivate a schedule that was
5397 * not active.
5398 */
5399 if (!activate && *parameter_value == 0) {
5400 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
5401 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5402 goto end;
5403 }
5404
5405 /*
5406 * Reject the command if we were asked to deactivate a schedule that
5407 * doesn't exist.
5408 */
5409 if (!activate && *parameter_value != new_value) {
5410 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
5411 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
5412 goto end;
5413 }
5414
5415 *parameter_value = activate ? new_value : 0;
5416
5417 switch (schedule_type) {
5418 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
5419 if (activate && session->active) {
5420 /*
5421 * Only start the timer if the session is active,
5422 * otherwise it will be started when the session starts.
5423 */
5424 ret = timer_session_rotation_schedule_timer_start(
5425 session, new_value);
5426 if (ret) {
5427 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
5428 ret = LTTNG_ERR_UNK;
5429 goto end;
5430 }
5431 } else {
5432 ret = timer_session_rotation_schedule_timer_stop(
5433 session);
5434 if (ret) {
5435 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
5436 ret = LTTNG_ERR_UNK;
5437 goto end;
5438 }
5439 }
5440 break;
5441 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
5442 if (activate) {
5443 ret = subscribe_session_consumed_size_rotation(session,
5444 new_value, notification_thread_handle);
5445 if (ret) {
5446 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
5447 ret = LTTNG_ERR_UNK;
5448 goto end;
5449 }
5450 } else {
5451 ret = unsubscribe_session_consumed_size_rotation(session,
5452 notification_thread_handle);
5453 if (ret) {
5454 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
5455 ret = LTTNG_ERR_UNK;
5456 goto end;
5457 }
5458
5459 }
5460 break;
5461 default:
5462 /* Would have been caught before. */
5463 abort();
5464 }
5465
5466 ret = LTTNG_OK;
5467
5468 goto end;
5469
5470 end:
5471 return ret;
5472 }
5473
5474 /* Wait for a given path to be removed before continuing. */
5475 static enum lttng_error_code wait_on_path(void *path_data)
5476 {
5477 const char *shm_path = path_data;
5478
5479 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5480 shm_path);
5481 while (true) {
5482 int ret;
5483 struct stat st;
5484
5485 ret = stat(shm_path, &st);
5486 if (ret) {
5487 if (errno != ENOENT) {
5488 PERROR("stat() returned an error while checking for the existence of the shm path");
5489 } else {
5490 DBG("shm path no longer exists, completing the destruction of session");
5491 }
5492 break;
5493 } else {
5494 if (!S_ISDIR(st.st_mode)) {
5495 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5496 shm_path);
5497 break;
5498 }
5499 }
5500 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
5501 }
5502 return LTTNG_OK;
5503 }
5504
5505 /*
5506 * Returns a pointer to a handler to run on completion of a command.
5507 * Returns NULL if no handler has to be run for the last command executed.
5508 */
5509 const struct cmd_completion_handler *cmd_pop_completion_handler(void)
5510 {
5511 struct cmd_completion_handler *handler = current_completion_handler;
5512
5513 current_completion_handler = NULL;
5514 return handler;
5515 }
5516
5517 /*
5518 * Init command subsystem.
5519 */
5520 void cmd_init(void)
5521 {
5522 /*
5523 * Set network sequence index to 1 for streams to match a relayd
5524 * socket on the consumer side.
5525 */
5526 pthread_mutex_lock(&relayd_net_seq_idx_lock);
5527 relayd_net_seq_idx = 1;
5528 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
5529
5530 DBG("Command subsystem initialized");
5531 }
LTTng tools - Deliverables
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