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Build a list of triggers applying to a given session on creation
[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c
1 /*
2 * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
3 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License, version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 51
16 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #define _LGPL_SOURCE
20 #include <assert.h>
21 #include <inttypes.h>
22 #include <urcu/list.h>
23 #include <urcu/uatomic.h>
24 #include <sys/stat.h>
25
26 #include <common/defaults.h>
27 #include <common/common.h>
28 #include <common/sessiond-comm/sessiond-comm.h>
29 #include <common/relayd/relayd.h>
30 #include <common/utils.h>
31 #include <common/compat/string.h>
32 #include <common/kernel-ctl/kernel-ctl.h>
33 #include <common/dynamic-buffer.h>
34 #include <common/buffer-view.h>
35 #include <lttng/trigger/trigger-internal.h>
36 #include <lttng/condition/condition.h>
37 #include <lttng/action/action.h>
38 #include <lttng/channel.h>
39 #include <lttng/channel-internal.h>
40 #include <lttng/rotate-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 "sessiond-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 static enum lttng_error_code wait_on_path(void *path);
67
68 /*
69 * Command completion handler that is used by the destroy command
70 * when a session that has a non-default shm_path is being destroyed.
71 *
72 * See comment in cmd_destroy_session() for the rationale.
73 */
74 static struct destroy_completion_handler {
75 struct cmd_completion_handler handler;
76 char shm_path[member_sizeof(struct ltt_session, shm_path)];
77 } destroy_completion_handler = {
78 .handler = {
79 .run = wait_on_path,
80 .data = destroy_completion_handler.shm_path
81 },
82 .shm_path = { 0 },
83 };
84
85 static struct cmd_completion_handler *current_completion_handler;
86
87 /*
88 * Used to keep a unique index for each relayd socket created where this value
89 * is associated with streams on the consumer so it can match the right relayd
90 * to send to. It must be accessed with the relayd_net_seq_idx_lock
91 * held.
92 */
93 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
94 static uint64_t relayd_net_seq_idx;
95
96 static int validate_ust_event_name(const char *);
97 static int cmd_enable_event_internal(struct ltt_session *session,
98 struct lttng_domain *domain,
99 char *channel_name, struct lttng_event *event,
100 char *filter_expression,
101 struct lttng_filter_bytecode *filter,
102 struct lttng_event_exclusion *exclusion,
103 int wpipe);
104
105 /*
106 * Create a session path used by list_lttng_sessions for the case that the
107 * session consumer is on the network.
108 */
109 static int build_network_session_path(char *dst, size_t size,
110 struct ltt_session *session)
111 {
112 int ret, kdata_port, udata_port;
113 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
114 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
115
116 assert(session);
117 assert(dst);
118
119 memset(tmp_urls, 0, sizeof(tmp_urls));
120 memset(tmp_uurl, 0, sizeof(tmp_uurl));
121
122 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
123
124 if (session->kernel_session && session->kernel_session->consumer) {
125 kuri = &session->kernel_session->consumer->dst.net.control;
126 kdata_port = session->kernel_session->consumer->dst.net.data.port;
127 }
128
129 if (session->ust_session && session->ust_session->consumer) {
130 uuri = &session->ust_session->consumer->dst.net.control;
131 udata_port = session->ust_session->consumer->dst.net.data.port;
132 }
133
134 if (uuri == NULL && kuri == NULL) {
135 uri = &session->consumer->dst.net.control;
136 kdata_port = session->consumer->dst.net.data.port;
137 } else if (kuri && uuri) {
138 ret = uri_compare(kuri, uuri);
139 if (ret) {
140 /* Not Equal */
141 uri = kuri;
142 /* Build uuri URL string */
143 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
144 if (ret < 0) {
145 goto error;
146 }
147 } else {
148 uri = kuri;
149 }
150 } else if (kuri && uuri == NULL) {
151 uri = kuri;
152 } else if (uuri && kuri == NULL) {
153 uri = uuri;
154 }
155
156 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
157 if (ret < 0) {
158 goto error;
159 }
160
161 /*
162 * Do we have a UST url set. If yes, this means we have both kernel and UST
163 * to print.
164 */
165 if (*tmp_uurl != '\0') {
166 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
167 tmp_urls, kdata_port, tmp_uurl, udata_port);
168 } else {
169 int dport;
170 if (kuri || (!kuri && !uuri)) {
171 dport = kdata_port;
172 } else {
173 /* No kernel URI, use the UST port. */
174 dport = udata_port;
175 }
176 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
177 }
178
179 error:
180 return ret;
181 }
182
183 /*
184 * Get run-time attributes if the session has been started (discarded events,
185 * lost packets).
186 */
187 static int get_kernel_runtime_stats(struct ltt_session *session,
188 struct ltt_kernel_channel *kchan, uint64_t *discarded_events,
189 uint64_t *lost_packets)
190 {
191 int ret;
192
193 if (!session->has_been_started) {
194 ret = 0;
195 *discarded_events = 0;
196 *lost_packets = 0;
197 goto end;
198 }
199
200 ret = consumer_get_discarded_events(session->id, kchan->key,
201 session->kernel_session->consumer,
202 discarded_events);
203 if (ret < 0) {
204 goto end;
205 }
206
207 ret = consumer_get_lost_packets(session->id, kchan->key,
208 session->kernel_session->consumer,
209 lost_packets);
210 if (ret < 0) {
211 goto end;
212 }
213
214 end:
215 return ret;
216 }
217
218 /*
219 * Get run-time attributes if the session has been started (discarded events,
220 * lost packets).
221 */
222 static int get_ust_runtime_stats(struct ltt_session *session,
223 struct ltt_ust_channel *uchan, uint64_t *discarded_events,
224 uint64_t *lost_packets)
225 {
226 int ret;
227 struct ltt_ust_session *usess;
228
229 if (!discarded_events || !lost_packets) {
230 ret = -1;
231 goto end;
232 }
233
234 usess = session->ust_session;
235 assert(discarded_events);
236 assert(lost_packets);
237
238 if (!usess || !session->has_been_started) {
239 *discarded_events = 0;
240 *lost_packets = 0;
241 ret = 0;
242 goto end;
243 }
244
245 if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
246 ret = ust_app_uid_get_channel_runtime_stats(usess->id,
247 &usess->buffer_reg_uid_list,
248 usess->consumer, uchan->id,
249 uchan->attr.overwrite,
250 discarded_events,
251 lost_packets);
252 } else if (usess->buffer_type == LTTNG_BUFFER_PER_PID) {
253 ret = ust_app_pid_get_channel_runtime_stats(usess,
254 uchan, usess->consumer,
255 uchan->attr.overwrite,
256 discarded_events,
257 lost_packets);
258 if (ret < 0) {
259 goto end;
260 }
261 *discarded_events += uchan->per_pid_closed_app_discarded;
262 *lost_packets += uchan->per_pid_closed_app_lost;
263 } else {
264 ERR("Unsupported buffer type");
265 assert(0);
266 ret = -1;
267 goto end;
268 }
269
270 end:
271 return ret;
272 }
273
274 /*
275 * Fill lttng_channel array of all channels.
276 */
277 static ssize_t list_lttng_channels(enum lttng_domain_type domain,
278 struct ltt_session *session, struct lttng_channel *channels,
279 struct lttng_channel_extended *chan_exts)
280 {
281 int i = 0, ret = 0;
282 struct ltt_kernel_channel *kchan;
283
284 DBG("Listing channels for session %s", session->name);
285
286 switch (domain) {
287 case LTTNG_DOMAIN_KERNEL:
288 /* Kernel channels */
289 if (session->kernel_session != NULL) {
290 cds_list_for_each_entry(kchan,
291 &session->kernel_session->channel_list.head, list) {
292 uint64_t discarded_events, lost_packets;
293 struct lttng_channel_extended *extended;
294
295 extended = (struct lttng_channel_extended *)
296 kchan->channel->attr.extended.ptr;
297
298 ret = get_kernel_runtime_stats(session, kchan,
299 &discarded_events, &lost_packets);
300 if (ret < 0) {
301 goto end;
302 }
303 /* Copy lttng_channel struct to array */
304 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
305 channels[i].enabled = kchan->enabled;
306 chan_exts[i].discarded_events =
307 discarded_events;
308 chan_exts[i].lost_packets = lost_packets;
309 chan_exts[i].monitor_timer_interval =
310 extended->monitor_timer_interval;
311 chan_exts[i].blocking_timeout = 0;
312 i++;
313 }
314 }
315 break;
316 case LTTNG_DOMAIN_UST:
317 {
318 struct lttng_ht_iter iter;
319 struct ltt_ust_channel *uchan;
320
321 rcu_read_lock();
322 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
323 &iter.iter, uchan, node.node) {
324 uint64_t discarded_events = 0, lost_packets = 0;
325
326 if (lttng_strncpy(channels[i].name, uchan->name,
327 LTTNG_SYMBOL_NAME_LEN)) {
328 break;
329 }
330 channels[i].attr.overwrite = uchan->attr.overwrite;
331 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
332 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
333 channels[i].attr.switch_timer_interval =
334 uchan->attr.switch_timer_interval;
335 channels[i].attr.read_timer_interval =
336 uchan->attr.read_timer_interval;
337 channels[i].enabled = uchan->enabled;
338 channels[i].attr.tracefile_size = uchan->tracefile_size;
339 channels[i].attr.tracefile_count = uchan->tracefile_count;
340
341 /*
342 * Map enum lttng_ust_output to enum lttng_event_output.
343 */
344 switch (uchan->attr.output) {
345 case LTTNG_UST_MMAP:
346 channels[i].attr.output = LTTNG_EVENT_MMAP;
347 break;
348 default:
349 /*
350 * LTTNG_UST_MMAP is the only supported UST
351 * output mode.
352 */
353 assert(0);
354 break;
355 }
356
357 chan_exts[i].monitor_timer_interval =
358 uchan->monitor_timer_interval;
359 chan_exts[i].blocking_timeout =
360 uchan->attr.u.s.blocking_timeout;
361
362 ret = get_ust_runtime_stats(session, uchan,
363 &discarded_events, &lost_packets);
364 if (ret < 0) {
365 break;
366 }
367 chan_exts[i].discarded_events = discarded_events;
368 chan_exts[i].lost_packets = lost_packets;
369 i++;
370 }
371 rcu_read_unlock();
372 break;
373 }
374 default:
375 break;
376 }
377
378 end:
379 if (ret < 0) {
380 return -LTTNG_ERR_FATAL;
381 } else {
382 return LTTNG_OK;
383 }
384 }
385
386 static void increment_extended_len(const char *filter_expression,
387 struct lttng_event_exclusion *exclusion, size_t *extended_len)
388 {
389 *extended_len += sizeof(struct lttcomm_event_extended_header);
390
391 if (filter_expression) {
392 *extended_len += strlen(filter_expression) + 1;
393 }
394
395 if (exclusion) {
396 *extended_len += exclusion->count * LTTNG_SYMBOL_NAME_LEN;
397 }
398 }
399
400 static void append_extended_info(const char *filter_expression,
401 struct lttng_event_exclusion *exclusion, void **extended_at)
402 {
403 struct lttcomm_event_extended_header extended_header;
404 size_t filter_len = 0;
405 size_t nb_exclusions = 0;
406
407 if (filter_expression) {
408 filter_len = strlen(filter_expression) + 1;
409 }
410
411 if (exclusion) {
412 nb_exclusions = exclusion->count;
413 }
414
415 /* Set header fields */
416 extended_header.filter_len = filter_len;
417 extended_header.nb_exclusions = nb_exclusions;
418
419 /* Copy header */
420 memcpy(*extended_at, &extended_header, sizeof(extended_header));
421 *extended_at += sizeof(extended_header);
422
423 /* Copy filter string */
424 if (filter_expression) {
425 memcpy(*extended_at, filter_expression, filter_len);
426 *extended_at += filter_len;
427 }
428
429 /* Copy exclusion names */
430 if (exclusion) {
431 size_t len = nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
432
433 memcpy(*extended_at, &exclusion->names, len);
434 *extended_at += len;
435 }
436 }
437
438 /*
439 * Create a list of agent domain events.
440 *
441 * Return number of events in list on success or else a negative value.
442 */
443 static int list_lttng_agent_events(struct agent *agt,
444 struct lttng_event **events, size_t *total_size)
445 {
446 int i = 0, ret = 0;
447 unsigned int nb_event = 0;
448 struct agent_event *event;
449 struct lttng_event *tmp_events;
450 struct lttng_ht_iter iter;
451 size_t extended_len = 0;
452 void *extended_at;
453
454 assert(agt);
455 assert(events);
456
457 DBG3("Listing agent events");
458
459 rcu_read_lock();
460 nb_event = lttng_ht_get_count(agt->events);
461 rcu_read_unlock();
462 if (nb_event == 0) {
463 ret = nb_event;
464 *total_size = 0;
465 goto error;
466 }
467
468 /* Compute required extended infos size */
469 extended_len = nb_event * sizeof(struct lttcomm_event_extended_header);
470
471 /*
472 * This is only valid because the commands which add events are
473 * processed in the same thread as the listing.
474 */
475 rcu_read_lock();
476 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
477 increment_extended_len(event->filter_expression, NULL,
478 &extended_len);
479 }
480 rcu_read_unlock();
481
482 *total_size = nb_event * sizeof(*tmp_events) + extended_len;
483 tmp_events = zmalloc(*total_size);
484 if (!tmp_events) {
485 PERROR("zmalloc agent events session");
486 ret = -LTTNG_ERR_FATAL;
487 goto error;
488 }
489
490 extended_at = ((uint8_t *) tmp_events) +
491 nb_event * sizeof(struct lttng_event);
492
493 rcu_read_lock();
494 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
495 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
496 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
497 tmp_events[i].enabled = event->enabled;
498 tmp_events[i].loglevel = event->loglevel_value;
499 tmp_events[i].loglevel_type = event->loglevel_type;
500 i++;
501
502 /* Append extended info */
503 append_extended_info(event->filter_expression, NULL,
504 &extended_at);
505 }
506 rcu_read_unlock();
507
508 *events = tmp_events;
509 ret = nb_event;
510
511 error:
512 assert(nb_event == i);
513 return ret;
514 }
515
516 /*
517 * Create a list of ust global domain events.
518 */
519 static int list_lttng_ust_global_events(char *channel_name,
520 struct ltt_ust_domain_global *ust_global,
521 struct lttng_event **events, size_t *total_size)
522 {
523 int i = 0, ret = 0;
524 unsigned int nb_event = 0;
525 struct lttng_ht_iter iter;
526 struct lttng_ht_node_str *node;
527 struct ltt_ust_channel *uchan;
528 struct ltt_ust_event *uevent;
529 struct lttng_event *tmp;
530 size_t extended_len = 0;
531 void *extended_at;
532
533 DBG("Listing UST global events for channel %s", channel_name);
534
535 rcu_read_lock();
536
537 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
538 node = lttng_ht_iter_get_node_str(&iter);
539 if (node == NULL) {
540 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
541 goto end;
542 }
543
544 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
545
546 nb_event = lttng_ht_get_count(uchan->events);
547 if (nb_event == 0) {
548 ret = nb_event;
549 *total_size = 0;
550 goto end;
551 }
552
553 DBG3("Listing UST global %d events", nb_event);
554
555 /* Compute required extended infos size */
556 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
557 if (uevent->internal) {
558 nb_event--;
559 continue;
560 }
561
562 increment_extended_len(uevent->filter_expression,
563 uevent->exclusion, &extended_len);
564 }
565 if (nb_event == 0) {
566 /* All events are internal, skip. */
567 ret = 0;
568 *total_size = 0;
569 goto end;
570 }
571
572 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
573 tmp = zmalloc(*total_size);
574 if (tmp == NULL) {
575 ret = -LTTNG_ERR_FATAL;
576 goto end;
577 }
578
579 extended_at = ((uint8_t *) tmp) + nb_event * sizeof(struct lttng_event);
580
581 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
582 if (uevent->internal) {
583 /* This event should remain hidden from clients */
584 continue;
585 }
586 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
587 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
588 tmp[i].enabled = uevent->enabled;
589
590 switch (uevent->attr.instrumentation) {
591 case LTTNG_UST_TRACEPOINT:
592 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
593 break;
594 case LTTNG_UST_PROBE:
595 tmp[i].type = LTTNG_EVENT_PROBE;
596 break;
597 case LTTNG_UST_FUNCTION:
598 tmp[i].type = LTTNG_EVENT_FUNCTION;
599 break;
600 }
601
602 tmp[i].loglevel = uevent->attr.loglevel;
603 switch (uevent->attr.loglevel_type) {
604 case LTTNG_UST_LOGLEVEL_ALL:
605 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
606 break;
607 case LTTNG_UST_LOGLEVEL_RANGE:
608 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
609 break;
610 case LTTNG_UST_LOGLEVEL_SINGLE:
611 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
612 break;
613 }
614 if (uevent->filter) {
615 tmp[i].filter = 1;
616 }
617 if (uevent->exclusion) {
618 tmp[i].exclusion = 1;
619 }
620 i++;
621
622 /* Append extended info */
623 append_extended_info(uevent->filter_expression,
624 uevent->exclusion, &extended_at);
625 }
626
627 ret = nb_event;
628 *events = tmp;
629 end:
630 rcu_read_unlock();
631 return ret;
632 }
633
634 /*
635 * Fill lttng_event array of all kernel events in the channel.
636 */
637 static int list_lttng_kernel_events(char *channel_name,
638 struct ltt_kernel_session *kernel_session,
639 struct lttng_event **events, size_t *total_size)
640 {
641 int i = 0, ret;
642 unsigned int nb_event;
643 struct ltt_kernel_event *event;
644 struct ltt_kernel_channel *kchan;
645 size_t extended_len = 0;
646 void *extended_at;
647
648 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
649 if (kchan == NULL) {
650 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
651 goto error;
652 }
653
654 nb_event = kchan->event_count;
655
656 DBG("Listing events for channel %s", kchan->channel->name);
657
658 if (nb_event == 0) {
659 *total_size = 0;
660 *events = NULL;
661 goto end;
662 }
663
664 /* Compute required extended infos size */
665 cds_list_for_each_entry(event, &kchan->events_list.head, list) {
666 increment_extended_len(event->filter_expression, NULL,
667 &extended_len);
668 }
669
670 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
671 *events = zmalloc(*total_size);
672 if (*events == NULL) {
673 ret = LTTNG_ERR_FATAL;
674 goto error;
675 }
676
677 extended_at = ((void *) *events) +
678 nb_event * sizeof(struct lttng_event);
679
680 /* Kernel channels */
681 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
682 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
683 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
684 (*events)[i].enabled = event->enabled;
685 (*events)[i].filter =
686 (unsigned char) !!event->filter_expression;
687
688 switch (event->event->instrumentation) {
689 case LTTNG_KERNEL_TRACEPOINT:
690 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
691 break;
692 case LTTNG_KERNEL_KRETPROBE:
693 (*events)[i].type = LTTNG_EVENT_FUNCTION;
694 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
695 sizeof(struct lttng_kernel_kprobe));
696 break;
697 case LTTNG_KERNEL_KPROBE:
698 (*events)[i].type = LTTNG_EVENT_PROBE;
699 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
700 sizeof(struct lttng_kernel_kprobe));
701 break;
702 case LTTNG_KERNEL_FUNCTION:
703 (*events)[i].type = LTTNG_EVENT_FUNCTION;
704 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
705 sizeof(struct lttng_kernel_function));
706 break;
707 case LTTNG_KERNEL_NOOP:
708 (*events)[i].type = LTTNG_EVENT_NOOP;
709 break;
710 case LTTNG_KERNEL_SYSCALL:
711 (*events)[i].type = LTTNG_EVENT_SYSCALL;
712 break;
713 case LTTNG_KERNEL_ALL:
714 assert(0);
715 break;
716 }
717 i++;
718
719 /* Append extended info */
720 append_extended_info(event->filter_expression, NULL,
721 &extended_at);
722 }
723
724 end:
725 return nb_event;
726
727 error:
728 /* Negate the error code to differentiate the size from an error */
729 return -ret;
730 }
731
732 /*
733 * Add URI so the consumer output object. Set the correct path depending on the
734 * domain adding the default trace directory.
735 */
736 static int add_uri_to_consumer(struct consumer_output *consumer,
737 struct lttng_uri *uri, enum lttng_domain_type domain,
738 const char *session_name)
739 {
740 int ret = LTTNG_OK;
741 const char *default_trace_dir;
742
743 assert(uri);
744
745 if (consumer == NULL) {
746 DBG("No consumer detected. Don't add URI. Stopping.");
747 ret = LTTNG_ERR_NO_CONSUMER;
748 goto error;
749 }
750
751 switch (domain) {
752 case LTTNG_DOMAIN_KERNEL:
753 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
754 break;
755 case LTTNG_DOMAIN_UST:
756 default_trace_dir = DEFAULT_UST_TRACE_DIR;
757 break;
758 default:
759 /*
760 * This case is possible is we try to add the URI to the global tracing
761 * session consumer object which in this case there is no subdir.
762 */
763 default_trace_dir = "";
764 }
765
766 switch (uri->dtype) {
767 case LTTNG_DST_IPV4:
768 case LTTNG_DST_IPV6:
769 DBG2("Setting network URI to consumer");
770
771 if (consumer->type == CONSUMER_DST_NET) {
772 if ((uri->stype == LTTNG_STREAM_CONTROL &&
773 consumer->dst.net.control_isset) ||
774 (uri->stype == LTTNG_STREAM_DATA &&
775 consumer->dst.net.data_isset)) {
776 ret = LTTNG_ERR_URL_EXIST;
777 goto error;
778 }
779 } else {
780 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
781 }
782
783 consumer->type = CONSUMER_DST_NET;
784
785 /* Set URI into consumer output object */
786 ret = consumer_set_network_uri(consumer, uri);
787 if (ret < 0) {
788 ret = -ret;
789 goto error;
790 } else if (ret == 1) {
791 /*
792 * URI was the same in the consumer so we do not append the subdir
793 * again so to not duplicate output dir.
794 */
795 ret = LTTNG_OK;
796 goto error;
797 }
798
799 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
800 ret = consumer_set_subdir(consumer, session_name);
801 if (ret < 0) {
802 ret = LTTNG_ERR_FATAL;
803 goto error;
804 }
805 }
806
807 if (uri->stype == LTTNG_STREAM_CONTROL) {
808 /* On a new subdir, reappend the default trace dir. */
809 strncat(consumer->subdir, default_trace_dir,
810 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
811 DBG3("Append domain trace name to subdir %s", consumer->subdir);
812 }
813
814 break;
815 case LTTNG_DST_PATH:
816 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
817 memset(consumer->dst.session_root_path, 0,
818 sizeof(consumer->dst.session_root_path));
819 /* Explicit length checks for strcpy and strcat. */
820 if (strlen(uri->dst.path) + strlen(default_trace_dir)
821 >= sizeof(consumer->dst.session_root_path)) {
822 ret = LTTNG_ERR_FATAL;
823 goto error;
824 }
825 strcpy(consumer->dst.session_root_path, uri->dst.path);
826 /* Append default trace dir */
827 strcat(consumer->dst.session_root_path, default_trace_dir);
828 /* Flag consumer as local. */
829 consumer->type = CONSUMER_DST_LOCAL;
830 break;
831 }
832
833 ret = LTTNG_OK;
834
835 error:
836 return ret;
837 }
838
839 /*
840 * Init tracing by creating trace directory and sending fds kernel consumer.
841 */
842 static int init_kernel_tracing(struct ltt_kernel_session *session)
843 {
844 int ret = 0;
845 struct lttng_ht_iter iter;
846 struct consumer_socket *socket;
847
848 assert(session);
849
850 rcu_read_lock();
851
852 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
853 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
854 socket, node.node) {
855 pthread_mutex_lock(socket->lock);
856 ret = kernel_consumer_send_session(socket, session);
857 pthread_mutex_unlock(socket->lock);
858 if (ret < 0) {
859 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
860 goto error;
861 }
862 }
863 }
864
865 error:
866 rcu_read_unlock();
867 return ret;
868 }
869
870 /*
871 * Create a socket to the relayd using the URI.
872 *
873 * On success, the relayd_sock pointer is set to the created socket.
874 * Else, it's stays untouched and a lttcomm error code is returned.
875 */
876 static int create_connect_relayd(struct lttng_uri *uri,
877 struct lttcomm_relayd_sock **relayd_sock,
878 struct consumer_output *consumer)
879 {
880 int ret;
881 struct lttcomm_relayd_sock *rsock;
882
883 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
884 RELAYD_VERSION_COMM_MINOR);
885 if (!rsock) {
886 ret = LTTNG_ERR_FATAL;
887 goto error;
888 }
889
890 /*
891 * Connect to relayd so we can proceed with a session creation. This call
892 * can possibly block for an arbitrary amount of time to set the health
893 * state to be in poll execution.
894 */
895 health_poll_entry();
896 ret = relayd_connect(rsock);
897 health_poll_exit();
898 if (ret < 0) {
899 ERR("Unable to reach lttng-relayd");
900 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
901 goto free_sock;
902 }
903
904 /* Create socket for control stream. */
905 if (uri->stype == LTTNG_STREAM_CONTROL) {
906 DBG3("Creating relayd stream socket from URI");
907
908 /* Check relayd version */
909 ret = relayd_version_check(rsock);
910 if (ret == LTTNG_ERR_RELAYD_VERSION_FAIL) {
911 goto close_sock;
912 } else if (ret < 0) {
913 ERR("Unable to reach lttng-relayd");
914 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
915 goto close_sock;
916 }
917 consumer->relay_major_version = rsock->major;
918 consumer->relay_minor_version = rsock->minor;
919 } else if (uri->stype == LTTNG_STREAM_DATA) {
920 DBG3("Creating relayd data socket from URI");
921 } else {
922 /* Command is not valid */
923 ERR("Relayd invalid stream type: %d", uri->stype);
924 ret = LTTNG_ERR_INVALID;
925 goto close_sock;
926 }
927
928 *relayd_sock = rsock;
929
930 return LTTNG_OK;
931
932 close_sock:
933 /* The returned value is not useful since we are on an error path. */
934 (void) relayd_close(rsock);
935 free_sock:
936 free(rsock);
937 error:
938 return ret;
939 }
940
941 /*
942 * Connect to the relayd using URI and send the socket to the right consumer.
943 *
944 * The consumer socket lock must be held by the caller.
945 */
946 static int send_consumer_relayd_socket(unsigned int session_id,
947 struct lttng_uri *relayd_uri,
948 struct consumer_output *consumer,
949 struct consumer_socket *consumer_sock,
950 char *session_name, char *hostname, int session_live_timer)
951 {
952 int ret;
953 struct lttcomm_relayd_sock *rsock = NULL;
954
955 /* Connect to relayd and make version check if uri is the control. */
956 ret = create_connect_relayd(relayd_uri, &rsock, consumer);
957 if (ret != LTTNG_OK) {
958 goto relayd_comm_error;
959 }
960 assert(rsock);
961
962 /* Set the network sequence index if not set. */
963 if (consumer->net_seq_index == (uint64_t) -1ULL) {
964 pthread_mutex_lock(&relayd_net_seq_idx_lock);
965 /*
966 * Increment net_seq_idx because we are about to transfer the
967 * new relayd socket to the consumer.
968 * Assign unique key so the consumer can match streams.
969 */
970 consumer->net_seq_index = ++relayd_net_seq_idx;
971 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
972 }
973
974 /* Send relayd socket to consumer. */
975 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
976 relayd_uri->stype, session_id,
977 session_name, hostname, session_live_timer);
978 if (ret < 0) {
979 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
980 goto close_sock;
981 }
982
983 /* Flag that the corresponding socket was sent. */
984 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
985 consumer_sock->control_sock_sent = 1;
986 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
987 consumer_sock->data_sock_sent = 1;
988 }
989
990 ret = LTTNG_OK;
991
992 /*
993 * Close socket which was dup on the consumer side. The session daemon does
994 * NOT keep track of the relayd socket(s) once transfer to the consumer.
995 */
996
997 close_sock:
998 if (ret != LTTNG_OK) {
999 /*
1000 * The consumer output for this session should not be used anymore
1001 * since the relayd connection failed thus making any tracing or/and
1002 * streaming not usable.
1003 */
1004 consumer->enabled = 0;
1005 }
1006 (void) relayd_close(rsock);
1007 free(rsock);
1008
1009 relayd_comm_error:
1010 return ret;
1011 }
1012
1013 /*
1014 * Send both relayd sockets to a specific consumer and domain. This is a
1015 * helper function to facilitate sending the information to the consumer for a
1016 * session.
1017 *
1018 * The consumer socket lock must be held by the caller.
1019 */
1020 static int send_consumer_relayd_sockets(enum lttng_domain_type domain,
1021 unsigned int session_id, struct consumer_output *consumer,
1022 struct consumer_socket *sock, char *session_name,
1023 char *hostname, int session_live_timer)
1024 {
1025 int ret = LTTNG_OK;
1026
1027 assert(consumer);
1028 assert(sock);
1029
1030 /* Sending control relayd socket. */
1031 if (!sock->control_sock_sent) {
1032 ret = send_consumer_relayd_socket(session_id,
1033 &consumer->dst.net.control, consumer, sock,
1034 session_name, hostname, session_live_timer);
1035 if (ret != LTTNG_OK) {
1036 goto error;
1037 }
1038 }
1039
1040 /* Sending data relayd socket. */
1041 if (!sock->data_sock_sent) {
1042 ret = send_consumer_relayd_socket(session_id,
1043 &consumer->dst.net.data, consumer, sock,
1044 session_name, hostname, session_live_timer);
1045 if (ret != LTTNG_OK) {
1046 goto error;
1047 }
1048 }
1049
1050 error:
1051 return ret;
1052 }
1053
1054 /*
1055 * Setup relayd connections for a tracing session. First creates the socket to
1056 * the relayd and send them to the right domain consumer. Consumer type MUST be
1057 * network.
1058 */
1059 int cmd_setup_relayd(struct ltt_session *session)
1060 {
1061 int ret = LTTNG_OK;
1062 struct ltt_ust_session *usess;
1063 struct ltt_kernel_session *ksess;
1064 struct consumer_socket *socket;
1065 struct lttng_ht_iter iter;
1066
1067 assert(session);
1068
1069 usess = session->ust_session;
1070 ksess = session->kernel_session;
1071
1072 DBG("Setting relayd for session %s", session->name);
1073
1074 rcu_read_lock();
1075
1076 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1077 && usess->consumer->enabled) {
1078 /* For each consumer socket, send relayd sockets */
1079 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1080 socket, node.node) {
1081 pthread_mutex_lock(socket->lock);
1082 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1083 usess->consumer, socket,
1084 session->name, session->hostname,
1085 session->live_timer);
1086 pthread_mutex_unlock(socket->lock);
1087 if (ret != LTTNG_OK) {
1088 goto error;
1089 }
1090 /* Session is now ready for network streaming. */
1091 session->net_handle = 1;
1092 }
1093 session->consumer->relay_major_version =
1094 usess->consumer->relay_major_version;
1095 session->consumer->relay_minor_version =
1096 usess->consumer->relay_minor_version;
1097 }
1098
1099 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1100 && ksess->consumer->enabled) {
1101 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1102 socket, node.node) {
1103 pthread_mutex_lock(socket->lock);
1104 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1105 ksess->consumer, socket,
1106 session->name, session->hostname,
1107 session->live_timer);
1108 pthread_mutex_unlock(socket->lock);
1109 if (ret != LTTNG_OK) {
1110 goto error;
1111 }
1112 /* Session is now ready for network streaming. */
1113 session->net_handle = 1;
1114 }
1115 session->consumer->relay_major_version =
1116 ksess->consumer->relay_major_version;
1117 session->consumer->relay_minor_version =
1118 ksess->consumer->relay_minor_version;
1119 }
1120
1121 error:
1122 rcu_read_unlock();
1123 return ret;
1124 }
1125
1126 /*
1127 * Start a kernel session by opening all necessary streams.
1128 */
1129 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
1130 {
1131 int ret;
1132 struct ltt_kernel_channel *kchan;
1133
1134 /* Open kernel metadata */
1135 if (ksess->metadata == NULL && ksess->output_traces) {
1136 ret = kernel_open_metadata(ksess);
1137 if (ret < 0) {
1138 ret = LTTNG_ERR_KERN_META_FAIL;
1139 goto error;
1140 }
1141 }
1142
1143 /* Open kernel metadata stream */
1144 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1145 ret = kernel_open_metadata_stream(ksess);
1146 if (ret < 0) {
1147 ERR("Kernel create metadata stream failed");
1148 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1149 goto error;
1150 }
1151 }
1152
1153 /* For each channel */
1154 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1155 if (kchan->stream_count == 0) {
1156 ret = kernel_open_channel_stream(kchan);
1157 if (ret < 0) {
1158 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1159 goto error;
1160 }
1161 /* Update the stream global counter */
1162 ksess->stream_count_global += ret;
1163 }
1164 }
1165
1166 /* Setup kernel consumer socket and send fds to it */
1167 ret = init_kernel_tracing(ksess);
1168 if (ret != 0) {
1169 ret = LTTNG_ERR_KERN_START_FAIL;
1170 goto error;
1171 }
1172
1173 /* This start the kernel tracing */
1174 ret = kernel_start_session(ksess);
1175 if (ret < 0) {
1176 ret = LTTNG_ERR_KERN_START_FAIL;
1177 goto error;
1178 }
1179
1180 /* Quiescent wait after starting trace */
1181 kernel_wait_quiescent(wpipe);
1182
1183 ksess->active = 1;
1184
1185 ret = LTTNG_OK;
1186
1187 error:
1188 return ret;
1189 }
1190
1191 /*
1192 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1193 */
1194 int cmd_disable_channel(struct ltt_session *session,
1195 enum lttng_domain_type domain, char *channel_name)
1196 {
1197 int ret;
1198 struct ltt_ust_session *usess;
1199
1200 usess = session->ust_session;
1201
1202 rcu_read_lock();
1203
1204 switch (domain) {
1205 case LTTNG_DOMAIN_KERNEL:
1206 {
1207 ret = channel_kernel_disable(session->kernel_session,
1208 channel_name);
1209 if (ret != LTTNG_OK) {
1210 goto error;
1211 }
1212
1213 kernel_wait_quiescent(kernel_tracer_fd);
1214 break;
1215 }
1216 case LTTNG_DOMAIN_UST:
1217 {
1218 struct ltt_ust_channel *uchan;
1219 struct lttng_ht *chan_ht;
1220
1221 chan_ht = usess->domain_global.channels;
1222
1223 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1224 if (uchan == NULL) {
1225 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1226 goto error;
1227 }
1228
1229 ret = channel_ust_disable(usess, uchan);
1230 if (ret != LTTNG_OK) {
1231 goto error;
1232 }
1233 break;
1234 }
1235 default:
1236 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1237 goto error;
1238 }
1239
1240 ret = LTTNG_OK;
1241
1242 error:
1243 rcu_read_unlock();
1244 return ret;
1245 }
1246
1247 /*
1248 * Command LTTNG_TRACK_PID processed by the client thread.
1249 *
1250 * Called with session lock held.
1251 */
1252 int cmd_track_pid(struct ltt_session *session, enum lttng_domain_type domain,
1253 int pid)
1254 {
1255 int ret;
1256
1257 rcu_read_lock();
1258
1259 switch (domain) {
1260 case LTTNG_DOMAIN_KERNEL:
1261 {
1262 struct ltt_kernel_session *ksess;
1263
1264 ksess = session->kernel_session;
1265
1266 ret = kernel_track_pid(ksess, pid);
1267 if (ret != LTTNG_OK) {
1268 goto error;
1269 }
1270
1271 kernel_wait_quiescent(kernel_tracer_fd);
1272 break;
1273 }
1274 case LTTNG_DOMAIN_UST:
1275 {
1276 struct ltt_ust_session *usess;
1277
1278 usess = session->ust_session;
1279
1280 ret = trace_ust_track_pid(usess, pid);
1281 if (ret != LTTNG_OK) {
1282 goto error;
1283 }
1284 break;
1285 }
1286 default:
1287 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1288 goto error;
1289 }
1290
1291 ret = LTTNG_OK;
1292
1293 error:
1294 rcu_read_unlock();
1295 return ret;
1296 }
1297
1298 /*
1299 * Command LTTNG_UNTRACK_PID processed by the client thread.
1300 *
1301 * Called with session lock held.
1302 */
1303 int cmd_untrack_pid(struct ltt_session *session, enum lttng_domain_type domain,
1304 int pid)
1305 {
1306 int ret;
1307
1308 rcu_read_lock();
1309
1310 switch (domain) {
1311 case LTTNG_DOMAIN_KERNEL:
1312 {
1313 struct ltt_kernel_session *ksess;
1314
1315 ksess = session->kernel_session;
1316
1317 ret = kernel_untrack_pid(ksess, pid);
1318 if (ret != LTTNG_OK) {
1319 goto error;
1320 }
1321
1322 kernel_wait_quiescent(kernel_tracer_fd);
1323 break;
1324 }
1325 case LTTNG_DOMAIN_UST:
1326 {
1327 struct ltt_ust_session *usess;
1328
1329 usess = session->ust_session;
1330
1331 ret = trace_ust_untrack_pid(usess, pid);
1332 if (ret != LTTNG_OK) {
1333 goto error;
1334 }
1335 break;
1336 }
1337 default:
1338 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1339 goto error;
1340 }
1341
1342 ret = LTTNG_OK;
1343
1344 error:
1345 rcu_read_unlock();
1346 return ret;
1347 }
1348
1349 /*
1350 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1351 *
1352 * The wpipe arguments is used as a notifier for the kernel thread.
1353 */
1354 int cmd_enable_channel(struct ltt_session *session,
1355 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1356 {
1357 int ret;
1358 struct ltt_ust_session *usess = session->ust_session;
1359 struct lttng_ht *chan_ht;
1360 size_t len;
1361
1362 assert(session);
1363 assert(attr);
1364 assert(domain);
1365
1366 len = lttng_strnlen(attr->name, sizeof(attr->name));
1367
1368 /* Validate channel name */
1369 if (attr->name[0] == '.' ||
1370 memchr(attr->name, '/', len) != NULL) {
1371 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1372 goto end;
1373 }
1374
1375 DBG("Enabling channel %s for session %s", attr->name, session->name);
1376
1377 rcu_read_lock();
1378
1379 /*
1380 * Don't try to enable a channel if the session has been started at
1381 * some point in time before. The tracer does not allow it.
1382 */
1383 if (session->has_been_started) {
1384 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1385 goto error;
1386 }
1387
1388 /*
1389 * If the session is a live session, remove the switch timer, the
1390 * live timer does the same thing but sends also synchronisation
1391 * beacons for inactive streams.
1392 */
1393 if (session->live_timer > 0) {
1394 attr->attr.live_timer_interval = session->live_timer;
1395 attr->attr.switch_timer_interval = 0;
1396 }
1397
1398 /* Check for feature support */
1399 switch (domain->type) {
1400 case LTTNG_DOMAIN_KERNEL:
1401 {
1402 if (kernel_supports_ring_buffer_snapshot_sample_positions(kernel_tracer_fd) != 1) {
1403 /* Sampling position of buffer is not supported */
1404 WARN("Kernel tracer does not support buffer monitoring. "
1405 "Setting the monitor interval timer to 0 "
1406 "(disabled) for channel '%s' of session '%s'",
1407 attr-> name, session->name);
1408 lttng_channel_set_monitor_timer_interval(attr, 0);
1409 }
1410 break;
1411 }
1412 case LTTNG_DOMAIN_UST:
1413 break;
1414 case LTTNG_DOMAIN_JUL:
1415 case LTTNG_DOMAIN_LOG4J:
1416 case LTTNG_DOMAIN_PYTHON:
1417 if (!agent_tracing_is_enabled()) {
1418 DBG("Attempted to enable a channel in an agent domain but the agent thread is not running");
1419 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
1420 goto error;
1421 }
1422 break;
1423 default:
1424 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1425 goto error;
1426 }
1427
1428 switch (domain->type) {
1429 case LTTNG_DOMAIN_KERNEL:
1430 {
1431 struct ltt_kernel_channel *kchan;
1432
1433 kchan = trace_kernel_get_channel_by_name(attr->name,
1434 session->kernel_session);
1435 if (kchan == NULL) {
1436 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1437 if (attr->name[0] != '\0') {
1438 session->kernel_session->has_non_default_channel = 1;
1439 }
1440 } else {
1441 ret = channel_kernel_enable(session->kernel_session, kchan);
1442 }
1443
1444 if (ret != LTTNG_OK) {
1445 goto error;
1446 }
1447
1448 kernel_wait_quiescent(kernel_tracer_fd);
1449 break;
1450 }
1451 case LTTNG_DOMAIN_UST:
1452 case LTTNG_DOMAIN_JUL:
1453 case LTTNG_DOMAIN_LOG4J:
1454 case LTTNG_DOMAIN_PYTHON:
1455 {
1456 struct ltt_ust_channel *uchan;
1457
1458 /*
1459 * FIXME
1460 *
1461 * Current agent implementation limitations force us to allow
1462 * only one channel at once in "agent" subdomains. Each
1463 * subdomain has a default channel name which must be strictly
1464 * adhered to.
1465 */
1466 if (domain->type == LTTNG_DOMAIN_JUL) {
1467 if (strncmp(attr->name, DEFAULT_JUL_CHANNEL_NAME,
1468 LTTNG_SYMBOL_NAME_LEN)) {
1469 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1470 goto error;
1471 }
1472 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1473 if (strncmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME,
1474 LTTNG_SYMBOL_NAME_LEN)) {
1475 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1476 goto error;
1477 }
1478 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1479 if (strncmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME,
1480 LTTNG_SYMBOL_NAME_LEN)) {
1481 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1482 goto error;
1483 }
1484 }
1485
1486 chan_ht = usess->domain_global.channels;
1487
1488 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1489 if (uchan == NULL) {
1490 ret = channel_ust_create(usess, attr, domain->buf_type);
1491 if (attr->name[0] != '\0') {
1492 usess->has_non_default_channel = 1;
1493 }
1494 } else {
1495 ret = channel_ust_enable(usess, uchan);
1496 }
1497 break;
1498 }
1499 default:
1500 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1501 goto error;
1502 }
1503
1504 error:
1505 rcu_read_unlock();
1506 end:
1507 return ret;
1508 }
1509
1510 /*
1511 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1512 */
1513 int cmd_disable_event(struct ltt_session *session,
1514 enum lttng_domain_type domain, char *channel_name,
1515 struct lttng_event *event)
1516 {
1517 int ret;
1518 char *event_name;
1519
1520 DBG("Disable event command for event \'%s\'", event->name);
1521
1522 event_name = event->name;
1523
1524 /* Error out on unhandled search criteria */
1525 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1526 || event->pid || event->filter || event->exclusion) {
1527 ret = LTTNG_ERR_UNK;
1528 goto error;
1529 }
1530
1531 rcu_read_lock();
1532
1533 switch (domain) {
1534 case LTTNG_DOMAIN_KERNEL:
1535 {
1536 struct ltt_kernel_channel *kchan;
1537 struct ltt_kernel_session *ksess;
1538
1539 ksess = session->kernel_session;
1540
1541 /*
1542 * If a non-default channel has been created in the
1543 * session, explicitely require that -c chan_name needs
1544 * to be provided.
1545 */
1546 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1547 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1548 goto error_unlock;
1549 }
1550
1551 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1552 if (kchan == NULL) {
1553 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1554 goto error_unlock;
1555 }
1556
1557 switch (event->type) {
1558 case LTTNG_EVENT_ALL:
1559 case LTTNG_EVENT_TRACEPOINT:
1560 case LTTNG_EVENT_SYSCALL:
1561 case LTTNG_EVENT_PROBE:
1562 case LTTNG_EVENT_FUNCTION:
1563 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1564 if (event_name[0] == '\0') {
1565 ret = event_kernel_disable_event(kchan,
1566 NULL, event->type);
1567 } else {
1568 ret = event_kernel_disable_event(kchan,
1569 event_name, event->type);
1570 }
1571 if (ret != LTTNG_OK) {
1572 goto error_unlock;
1573 }
1574 break;
1575 default:
1576 ret = LTTNG_ERR_UNK;
1577 goto error_unlock;
1578 }
1579
1580 kernel_wait_quiescent(kernel_tracer_fd);
1581 break;
1582 }
1583 case LTTNG_DOMAIN_UST:
1584 {
1585 struct ltt_ust_channel *uchan;
1586 struct ltt_ust_session *usess;
1587
1588 usess = session->ust_session;
1589
1590 if (validate_ust_event_name(event_name)) {
1591 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1592 goto error_unlock;
1593 }
1594
1595 /*
1596 * If a non-default channel has been created in the
1597 * session, explicitly require that -c chan_name needs
1598 * to be provided.
1599 */
1600 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1601 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1602 goto error_unlock;
1603 }
1604
1605 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1606 channel_name);
1607 if (uchan == NULL) {
1608 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1609 goto error_unlock;
1610 }
1611
1612 switch (event->type) {
1613 case LTTNG_EVENT_ALL:
1614 /*
1615 * An empty event name means that everything
1616 * should be disabled.
1617 */
1618 if (event->name[0] == '\0') {
1619 ret = event_ust_disable_all_tracepoints(usess, uchan);
1620 } else {
1621 ret = event_ust_disable_tracepoint(usess, uchan,
1622 event_name);
1623 }
1624 if (ret != LTTNG_OK) {
1625 goto error_unlock;
1626 }
1627 break;
1628 default:
1629 ret = LTTNG_ERR_UNK;
1630 goto error_unlock;
1631 }
1632
1633 DBG3("Disable UST event %s in channel %s completed", event_name,
1634 channel_name);
1635 break;
1636 }
1637 case LTTNG_DOMAIN_LOG4J:
1638 case LTTNG_DOMAIN_JUL:
1639 case LTTNG_DOMAIN_PYTHON:
1640 {
1641 struct agent *agt;
1642 struct ltt_ust_session *usess = session->ust_session;
1643
1644 assert(usess);
1645
1646 switch (event->type) {
1647 case LTTNG_EVENT_ALL:
1648 break;
1649 default:
1650 ret = LTTNG_ERR_UNK;
1651 goto error_unlock;
1652 }
1653
1654 agt = trace_ust_find_agent(usess, domain);
1655 if (!agt) {
1656 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1657 goto error_unlock;
1658 }
1659 /*
1660 * An empty event name means that everything
1661 * should be disabled.
1662 */
1663 if (event->name[0] == '\0') {
1664 ret = event_agent_disable_all(usess, agt);
1665 } else {
1666 ret = event_agent_disable(usess, agt, event_name);
1667 }
1668 if (ret != LTTNG_OK) {
1669 goto error_unlock;
1670 }
1671
1672 break;
1673 }
1674 default:
1675 ret = LTTNG_ERR_UND;
1676 goto error_unlock;
1677 }
1678
1679 ret = LTTNG_OK;
1680
1681 error_unlock:
1682 rcu_read_unlock();
1683 error:
1684 return ret;
1685 }
1686
1687 /*
1688 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1689 */
1690 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1691 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1692 {
1693 int ret, chan_kern_created = 0, chan_ust_created = 0;
1694 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1695
1696 /*
1697 * Don't try to add a context if the session has been started at
1698 * some point in time before. The tracer does not allow it and would
1699 * result in a corrupted trace.
1700 */
1701 if (session->has_been_started) {
1702 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1703 goto end;
1704 }
1705
1706 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1707 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1708 app_ctx_name = ctx->u.app_ctx.ctx_name;
1709 }
1710
1711 switch (domain) {
1712 case LTTNG_DOMAIN_KERNEL:
1713 assert(session->kernel_session);
1714
1715 if (session->kernel_session->channel_count == 0) {
1716 /* Create default channel */
1717 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1718 if (ret != LTTNG_OK) {
1719 goto error;
1720 }
1721 chan_kern_created = 1;
1722 }
1723 /* Add kernel context to kernel tracer */
1724 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1725 if (ret != LTTNG_OK) {
1726 goto error;
1727 }
1728 break;
1729 case LTTNG_DOMAIN_JUL:
1730 case LTTNG_DOMAIN_LOG4J:
1731 {
1732 /*
1733 * Validate channel name.
1734 * If no channel name is given and the domain is JUL or LOG4J,
1735 * set it to the appropriate domain-specific channel name. If
1736 * a name is provided but does not match the expexted channel
1737 * name, return an error.
1738 */
1739 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1740 strcmp(channel_name,
1741 DEFAULT_JUL_CHANNEL_NAME)) {
1742 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1743 goto error;
1744 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1745 strcmp(channel_name,
1746 DEFAULT_LOG4J_CHANNEL_NAME)) {
1747 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1748 goto error;
1749 }
1750 /* break is _not_ missing here. */
1751 }
1752 case LTTNG_DOMAIN_UST:
1753 {
1754 struct ltt_ust_session *usess = session->ust_session;
1755 unsigned int chan_count;
1756
1757 assert(usess);
1758
1759 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1760 if (chan_count == 0) {
1761 struct lttng_channel *attr;
1762 /* Create default channel */
1763 attr = channel_new_default_attr(domain, usess->buffer_type);
1764 if (attr == NULL) {
1765 ret = LTTNG_ERR_FATAL;
1766 goto error;
1767 }
1768
1769 ret = channel_ust_create(usess, attr, usess->buffer_type);
1770 if (ret != LTTNG_OK) {
1771 free(attr);
1772 goto error;
1773 }
1774 channel_attr_destroy(attr);
1775 chan_ust_created = 1;
1776 }
1777
1778 ret = context_ust_add(usess, domain, ctx, channel_name);
1779 free(app_ctx_provider_name);
1780 free(app_ctx_name);
1781 app_ctx_name = NULL;
1782 app_ctx_provider_name = NULL;
1783 if (ret != LTTNG_OK) {
1784 goto error;
1785 }
1786 break;
1787 }
1788 default:
1789 ret = LTTNG_ERR_UND;
1790 goto error;
1791 }
1792
1793 ret = LTTNG_OK;
1794 goto end;
1795
1796 error:
1797 if (chan_kern_created) {
1798 struct ltt_kernel_channel *kchan =
1799 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1800 session->kernel_session);
1801 /* Created previously, this should NOT fail. */
1802 assert(kchan);
1803 kernel_destroy_channel(kchan);
1804 }
1805
1806 if (chan_ust_created) {
1807 struct ltt_ust_channel *uchan =
1808 trace_ust_find_channel_by_name(
1809 session->ust_session->domain_global.channels,
1810 DEFAULT_CHANNEL_NAME);
1811 /* Created previously, this should NOT fail. */
1812 assert(uchan);
1813 /* Remove from the channel list of the session. */
1814 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1815 uchan);
1816 trace_ust_destroy_channel(uchan);
1817 }
1818 end:
1819 free(app_ctx_provider_name);
1820 free(app_ctx_name);
1821 return ret;
1822 }
1823
1824 static inline bool name_starts_with(const char *name, const char *prefix)
1825 {
1826 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1827
1828 return !strncmp(name, prefix, max_cmp_len);
1829 }
1830
1831 /* Perform userspace-specific event name validation */
1832 static int validate_ust_event_name(const char *name)
1833 {
1834 int ret = 0;
1835
1836 if (!name) {
1837 ret = -1;
1838 goto end;
1839 }
1840
1841 /*
1842 * Check name against all internal UST event component namespaces used
1843 * by the agents.
1844 */
1845 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1846 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1847 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1848 ret = -1;
1849 }
1850
1851 end:
1852 return ret;
1853 }
1854
1855 /*
1856 * Internal version of cmd_enable_event() with a supplemental
1857 * "internal_event" flag which is used to enable internal events which should
1858 * be hidden from clients. Such events are used in the agent implementation to
1859 * enable the events through which all "agent" events are funeled.
1860 */
1861 static int _cmd_enable_event(struct ltt_session *session,
1862 struct lttng_domain *domain,
1863 char *channel_name, struct lttng_event *event,
1864 char *filter_expression,
1865 struct lttng_filter_bytecode *filter,
1866 struct lttng_event_exclusion *exclusion,
1867 int wpipe, bool internal_event)
1868 {
1869 int ret = 0, channel_created = 0;
1870 struct lttng_channel *attr = NULL;
1871
1872 assert(session);
1873 assert(event);
1874 assert(channel_name);
1875
1876 /* If we have a filter, we must have its filter expression */
1877 assert(!(!!filter_expression ^ !!filter));
1878
1879 /* Normalize event name as a globbing pattern */
1880 strutils_normalize_star_glob_pattern(event->name);
1881
1882 /* Normalize exclusion names as globbing patterns */
1883 if (exclusion) {
1884 size_t i;
1885
1886 for (i = 0; i < exclusion->count; i++) {
1887 char *name = LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
1888
1889 strutils_normalize_star_glob_pattern(name);
1890 }
1891 }
1892
1893 DBG("Enable event command for event \'%s\'", event->name);
1894
1895 rcu_read_lock();
1896
1897 switch (domain->type) {
1898 case LTTNG_DOMAIN_KERNEL:
1899 {
1900 struct ltt_kernel_channel *kchan;
1901
1902 /*
1903 * If a non-default channel has been created in the
1904 * session, explicitely require that -c chan_name needs
1905 * to be provided.
1906 */
1907 if (session->kernel_session->has_non_default_channel
1908 && channel_name[0] == '\0') {
1909 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1910 goto error;
1911 }
1912
1913 kchan = trace_kernel_get_channel_by_name(channel_name,
1914 session->kernel_session);
1915 if (kchan == NULL) {
1916 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1917 LTTNG_BUFFER_GLOBAL);
1918 if (attr == NULL) {
1919 ret = LTTNG_ERR_FATAL;
1920 goto error;
1921 }
1922 if (lttng_strncpy(attr->name, channel_name,
1923 sizeof(attr->name))) {
1924 ret = LTTNG_ERR_INVALID;
1925 goto error;
1926 }
1927
1928 ret = cmd_enable_channel(session, domain, attr, wpipe);
1929 if (ret != LTTNG_OK) {
1930 goto error;
1931 }
1932 channel_created = 1;
1933 }
1934
1935 /* Get the newly created kernel channel pointer */
1936 kchan = trace_kernel_get_channel_by_name(channel_name,
1937 session->kernel_session);
1938 if (kchan == NULL) {
1939 /* This sould not happen... */
1940 ret = LTTNG_ERR_FATAL;
1941 goto error;
1942 }
1943
1944 switch (event->type) {
1945 case LTTNG_EVENT_ALL:
1946 {
1947 char *filter_expression_a = NULL;
1948 struct lttng_filter_bytecode *filter_a = NULL;
1949
1950 /*
1951 * We need to duplicate filter_expression and filter,
1952 * because ownership is passed to first enable
1953 * event.
1954 */
1955 if (filter_expression) {
1956 filter_expression_a = strdup(filter_expression);
1957 if (!filter_expression_a) {
1958 ret = LTTNG_ERR_FATAL;
1959 goto error;
1960 }
1961 }
1962 if (filter) {
1963 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
1964 if (!filter_a) {
1965 free(filter_expression_a);
1966 ret = LTTNG_ERR_FATAL;
1967 goto error;
1968 }
1969 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
1970 }
1971 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
1972 ret = event_kernel_enable_event(kchan, event,
1973 filter_expression, filter);
1974 /* We have passed ownership */
1975 filter_expression = NULL;
1976 filter = NULL;
1977 if (ret != LTTNG_OK) {
1978 if (channel_created) {
1979 /* Let's not leak a useless channel. */
1980 kernel_destroy_channel(kchan);
1981 }
1982 free(filter_expression_a);
1983 free(filter_a);
1984 goto error;
1985 }
1986 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
1987 ret = event_kernel_enable_event(kchan, event,
1988 filter_expression_a, filter_a);
1989 /* We have passed ownership */
1990 filter_expression_a = NULL;
1991 filter_a = NULL;
1992 if (ret != LTTNG_OK) {
1993 goto error;
1994 }
1995 break;
1996 }
1997 case LTTNG_EVENT_PROBE:
1998 case LTTNG_EVENT_FUNCTION:
1999 case LTTNG_EVENT_FUNCTION_ENTRY:
2000 case LTTNG_EVENT_TRACEPOINT:
2001 ret = event_kernel_enable_event(kchan, event,
2002 filter_expression, filter);
2003 /* We have passed ownership */
2004 filter_expression = NULL;
2005 filter = NULL;
2006 if (ret != LTTNG_OK) {
2007 if (channel_created) {
2008 /* Let's not leak a useless channel. */
2009 kernel_destroy_channel(kchan);
2010 }
2011 goto error;
2012 }
2013 break;
2014 case LTTNG_EVENT_SYSCALL:
2015 ret = event_kernel_enable_event(kchan, event,
2016 filter_expression, filter);
2017 /* We have passed ownership */
2018 filter_expression = NULL;
2019 filter = NULL;
2020 if (ret != LTTNG_OK) {
2021 goto error;
2022 }
2023 break;
2024 default:
2025 ret = LTTNG_ERR_UNK;
2026 goto error;
2027 }
2028
2029 kernel_wait_quiescent(kernel_tracer_fd);
2030 break;
2031 }
2032 case LTTNG_DOMAIN_UST:
2033 {
2034 struct ltt_ust_channel *uchan;
2035 struct ltt_ust_session *usess = session->ust_session;
2036
2037 assert(usess);
2038
2039 /*
2040 * If a non-default channel has been created in the
2041 * session, explicitely require that -c chan_name needs
2042 * to be provided.
2043 */
2044 if (usess->has_non_default_channel && channel_name[0] == '\0') {
2045 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
2046 goto error;
2047 }
2048
2049 /* Get channel from global UST domain */
2050 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2051 channel_name);
2052 if (uchan == NULL) {
2053 /* Create default channel */
2054 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
2055 usess->buffer_type);
2056 if (attr == NULL) {
2057 ret = LTTNG_ERR_FATAL;
2058 goto error;
2059 }
2060 if (lttng_strncpy(attr->name, channel_name,
2061 sizeof(attr->name))) {
2062 ret = LTTNG_ERR_INVALID;
2063 goto error;
2064 }
2065
2066 ret = cmd_enable_channel(session, domain, attr, wpipe);
2067 if (ret != LTTNG_OK) {
2068 goto error;
2069 }
2070
2071 /* Get the newly created channel reference back */
2072 uchan = trace_ust_find_channel_by_name(
2073 usess->domain_global.channels, channel_name);
2074 assert(uchan);
2075 }
2076
2077 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2078 /*
2079 * Don't allow users to add UST events to channels which
2080 * are assigned to a userspace subdomain (JUL, Log4J,
2081 * Python, etc.).
2082 */
2083 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2084 goto error;
2085 }
2086
2087 if (!internal_event) {
2088 /*
2089 * Ensure the event name is not reserved for internal
2090 * use.
2091 */
2092 ret = validate_ust_event_name(event->name);
2093 if (ret) {
2094 WARN("Userspace event name %s failed validation.",
2095 event->name ?
2096 event->name : "NULL");
2097 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2098 goto error;
2099 }
2100 }
2101
2102 /* At this point, the session and channel exist on the tracer */
2103 ret = event_ust_enable_tracepoint(usess, uchan, event,
2104 filter_expression, filter, exclusion,
2105 internal_event);
2106 /* We have passed ownership */
2107 filter_expression = NULL;
2108 filter = NULL;
2109 exclusion = NULL;
2110 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2111 goto already_enabled;
2112 } else if (ret != LTTNG_OK) {
2113 goto error;
2114 }
2115 break;
2116 }
2117 case LTTNG_DOMAIN_LOG4J:
2118 case LTTNG_DOMAIN_JUL:
2119 case LTTNG_DOMAIN_PYTHON:
2120 {
2121 const char *default_event_name, *default_chan_name;
2122 struct agent *agt;
2123 struct lttng_event uevent;
2124 struct lttng_domain tmp_dom;
2125 struct ltt_ust_session *usess = session->ust_session;
2126
2127 assert(usess);
2128
2129 if (!agent_tracing_is_enabled()) {
2130 DBG("Attempted to enable an event in an agent domain but the agent thread is not running");
2131 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
2132 goto error;
2133 }
2134
2135 agt = trace_ust_find_agent(usess, domain->type);
2136 if (!agt) {
2137 agt = agent_create(domain->type);
2138 if (!agt) {
2139 ret = LTTNG_ERR_NOMEM;
2140 goto error;
2141 }
2142 agent_add(agt, usess->agents);
2143 }
2144
2145 /* Create the default tracepoint. */
2146 memset(&uevent, 0, sizeof(uevent));
2147 uevent.type = LTTNG_EVENT_TRACEPOINT;
2148 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2149 default_event_name = event_get_default_agent_ust_name(
2150 domain->type);
2151 if (!default_event_name) {
2152 ret = LTTNG_ERR_FATAL;
2153 goto error;
2154 }
2155 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2156 uevent.name[sizeof(uevent.name) - 1] = '\0';
2157
2158 /*
2159 * The domain type is changed because we are about to enable the
2160 * default channel and event for the JUL domain that are hardcoded.
2161 * This happens in the UST domain.
2162 */
2163 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2164 tmp_dom.type = LTTNG_DOMAIN_UST;
2165
2166 switch (domain->type) {
2167 case LTTNG_DOMAIN_LOG4J:
2168 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2169 break;
2170 case LTTNG_DOMAIN_JUL:
2171 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2172 break;
2173 case LTTNG_DOMAIN_PYTHON:
2174 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2175 break;
2176 default:
2177 /* The switch/case we are in makes this impossible */
2178 assert(0);
2179 }
2180
2181 {
2182 char *filter_expression_copy = NULL;
2183 struct lttng_filter_bytecode *filter_copy = NULL;
2184
2185 if (filter) {
2186 const size_t filter_size = sizeof(
2187 struct lttng_filter_bytecode)
2188 + filter->len;
2189
2190 filter_copy = zmalloc(filter_size);
2191 if (!filter_copy) {
2192 ret = LTTNG_ERR_NOMEM;
2193 goto error;
2194 }
2195 memcpy(filter_copy, filter, filter_size);
2196
2197 filter_expression_copy =
2198 strdup(filter_expression);
2199 if (!filter_expression) {
2200 ret = LTTNG_ERR_NOMEM;
2201 }
2202
2203 if (!filter_expression_copy || !filter_copy) {
2204 free(filter_expression_copy);
2205 free(filter_copy);
2206 goto error;
2207 }
2208 }
2209
2210 ret = cmd_enable_event_internal(session, &tmp_dom,
2211 (char *) default_chan_name,
2212 &uevent, filter_expression_copy,
2213 filter_copy, NULL, wpipe);
2214 }
2215
2216 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2217 goto already_enabled;
2218 } else if (ret != LTTNG_OK) {
2219 goto error;
2220 }
2221
2222 /* The wild card * means that everything should be enabled. */
2223 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2224 ret = event_agent_enable_all(usess, agt, event, filter,
2225 filter_expression);
2226 } else {
2227 ret = event_agent_enable(usess, agt, event, filter,
2228 filter_expression);
2229 }
2230 filter = NULL;
2231 filter_expression = NULL;
2232 if (ret != LTTNG_OK) {
2233 goto error;
2234 }
2235
2236 break;
2237 }
2238 default:
2239 ret = LTTNG_ERR_UND;
2240 goto error;
2241 }
2242
2243 ret = LTTNG_OK;
2244
2245 already_enabled:
2246 error:
2247 free(filter_expression);
2248 free(filter);
2249 free(exclusion);
2250 channel_attr_destroy(attr);
2251 rcu_read_unlock();
2252 return ret;
2253 }
2254
2255 /*
2256 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2257 * We own filter, exclusion, and filter_expression.
2258 */
2259 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
2260 char *channel_name, struct lttng_event *event,
2261 char *filter_expression,
2262 struct lttng_filter_bytecode *filter,
2263 struct lttng_event_exclusion *exclusion,
2264 int wpipe)
2265 {
2266 return _cmd_enable_event(session, domain, channel_name, event,
2267 filter_expression, filter, exclusion, wpipe, false);
2268 }
2269
2270 /*
2271 * Enable an event which is internal to LTTng. An internal should
2272 * never be made visible to clients and are immune to checks such as
2273 * reserved names.
2274 */
2275 static int cmd_enable_event_internal(struct ltt_session *session,
2276 struct lttng_domain *domain,
2277 char *channel_name, struct lttng_event *event,
2278 char *filter_expression,
2279 struct lttng_filter_bytecode *filter,
2280 struct lttng_event_exclusion *exclusion,
2281 int wpipe)
2282 {
2283 return _cmd_enable_event(session, domain, channel_name, event,
2284 filter_expression, filter, exclusion, wpipe, true);
2285 }
2286
2287 /*
2288 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2289 */
2290 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2291 struct lttng_event **events)
2292 {
2293 int ret;
2294 ssize_t nb_events = 0;
2295
2296 switch (domain) {
2297 case LTTNG_DOMAIN_KERNEL:
2298 nb_events = kernel_list_events(kernel_tracer_fd, events);
2299 if (nb_events < 0) {
2300 ret = LTTNG_ERR_KERN_LIST_FAIL;
2301 goto error;
2302 }
2303 break;
2304 case LTTNG_DOMAIN_UST:
2305 nb_events = ust_app_list_events(events);
2306 if (nb_events < 0) {
2307 ret = LTTNG_ERR_UST_LIST_FAIL;
2308 goto error;
2309 }
2310 break;
2311 case LTTNG_DOMAIN_LOG4J:
2312 case LTTNG_DOMAIN_JUL:
2313 case LTTNG_DOMAIN_PYTHON:
2314 nb_events = agent_list_events(events, domain);
2315 if (nb_events < 0) {
2316 ret = LTTNG_ERR_UST_LIST_FAIL;
2317 goto error;
2318 }
2319 break;
2320 default:
2321 ret = LTTNG_ERR_UND;
2322 goto error;
2323 }
2324
2325 return nb_events;
2326
2327 error:
2328 /* Return negative value to differentiate return code */
2329 return -ret;
2330 }
2331
2332 /*
2333 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2334 */
2335 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2336 struct lttng_event_field **fields)
2337 {
2338 int ret;
2339 ssize_t nb_fields = 0;
2340
2341 switch (domain) {
2342 case LTTNG_DOMAIN_UST:
2343 nb_fields = ust_app_list_event_fields(fields);
2344 if (nb_fields < 0) {
2345 ret = LTTNG_ERR_UST_LIST_FAIL;
2346 goto error;
2347 }
2348 break;
2349 case LTTNG_DOMAIN_KERNEL:
2350 default: /* fall-through */
2351 ret = LTTNG_ERR_UND;
2352 goto error;
2353 }
2354
2355 return nb_fields;
2356
2357 error:
2358 /* Return negative value to differentiate return code */
2359 return -ret;
2360 }
2361
2362 ssize_t cmd_list_syscalls(struct lttng_event **events)
2363 {
2364 return syscall_table_list(events);
2365 }
2366
2367 /*
2368 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
2369 *
2370 * Called with session lock held.
2371 */
2372 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
2373 enum lttng_domain_type domain, int32_t **pids)
2374 {
2375 int ret;
2376 ssize_t nr_pids = 0;
2377
2378 switch (domain) {
2379 case LTTNG_DOMAIN_KERNEL:
2380 {
2381 struct ltt_kernel_session *ksess;
2382
2383 ksess = session->kernel_session;
2384 nr_pids = kernel_list_tracker_pids(ksess, pids);
2385 if (nr_pids < 0) {
2386 ret = LTTNG_ERR_KERN_LIST_FAIL;
2387 goto error;
2388 }
2389 break;
2390 }
2391 case LTTNG_DOMAIN_UST:
2392 {
2393 struct ltt_ust_session *usess;
2394
2395 usess = session->ust_session;
2396 nr_pids = trace_ust_list_tracker_pids(usess, pids);
2397 if (nr_pids < 0) {
2398 ret = LTTNG_ERR_UST_LIST_FAIL;
2399 goto error;
2400 }
2401 break;
2402 }
2403 case LTTNG_DOMAIN_LOG4J:
2404 case LTTNG_DOMAIN_JUL:
2405 case LTTNG_DOMAIN_PYTHON:
2406 default:
2407 ret = LTTNG_ERR_UND;
2408 goto error;
2409 }
2410
2411 return nr_pids;
2412
2413 error:
2414 /* Return negative value to differentiate return code */
2415 return -ret;
2416 }
2417
2418 static
2419 int domain_mkdir(const struct consumer_output *output,
2420 const struct ltt_session *session,
2421 uid_t uid, gid_t gid)
2422 {
2423 struct consumer_socket *socket;
2424 struct lttng_ht_iter iter;
2425 int ret;
2426 char *path = NULL;
2427
2428 if (!output || !output->socks) {
2429 ERR("No consumer output found");
2430 ret = -1;
2431 goto end;
2432 }
2433
2434 path = zmalloc(LTTNG_PATH_MAX * sizeof(char));
2435 if (!path) {
2436 ERR("Cannot allocate mkdir path");
2437 ret = -1;
2438 goto end;
2439 }
2440
2441 ret = snprintf(path, LTTNG_PATH_MAX, "%s%s%s",
2442 session_get_base_path(session),
2443 output->chunk_path, output->subdir);
2444 if (ret < 0 || ret >= LTTNG_PATH_MAX) {
2445 ERR("Format path");
2446 ret = -1;
2447 goto end;
2448 }
2449
2450 DBG("Domain mkdir %s for session %" PRIu64, path, session->id);
2451 rcu_read_lock();
2452 /*
2453 * We have to iterate to find a socket, but we only need to send the
2454 * rename command to one consumer, so we break after the first one.
2455 */
2456 cds_lfht_for_each_entry(output->socks->ht, &iter.iter, socket, node.node) {
2457 pthread_mutex_lock(socket->lock);
2458 ret = consumer_mkdir(socket, session->id, output, path, uid, gid);
2459 pthread_mutex_unlock(socket->lock);
2460 if (ret) {
2461 ERR("Consumer mkdir");
2462 ret = -1;
2463 goto end_unlock;
2464 }
2465 break;
2466 }
2467
2468 ret = 0;
2469
2470 end_unlock:
2471 rcu_read_unlock();
2472 end:
2473 free(path);
2474 return ret;
2475 }
2476
2477 static
2478 int session_mkdir(const struct ltt_session *session)
2479 {
2480 int ret;
2481 struct consumer_output *output;
2482 uid_t uid;
2483 gid_t gid;
2484
2485 /*
2486 * Unsupported feature in lttng-relayd before 2.11, not an error since it
2487 * is only needed for session rotation and the user will get an error
2488 * on rotate.
2489 */
2490 if (session->consumer->type == CONSUMER_DST_NET &&
2491 session->consumer->relay_major_version == 2 &&
2492 session->consumer->relay_minor_version < 11) {
2493 ret = 0;
2494 goto end;
2495 }
2496
2497 if (session->kernel_session) {
2498 output = session->kernel_session->consumer;
2499 uid = session->kernel_session->uid;
2500 gid = session->kernel_session->gid;
2501 ret = domain_mkdir(output, session, uid, gid);
2502 if (ret) {
2503 ERR("Mkdir kernel");
2504 goto end;
2505 }
2506 }
2507
2508 if (session->ust_session) {
2509 output = session->ust_session->consumer;
2510 uid = session->ust_session->uid;
2511 gid = session->ust_session->gid;
2512 ret = domain_mkdir(output, session, uid, gid);
2513 if (ret) {
2514 ERR("Mkdir UST");
2515 goto end;
2516 }
2517 }
2518
2519 ret = 0;
2520
2521 end:
2522 return ret;
2523 }
2524
2525 /*
2526 * Command LTTNG_START_TRACE processed by the client thread.
2527 *
2528 * Called with session mutex held.
2529 */
2530 int cmd_start_trace(struct ltt_session *session)
2531 {
2532 int ret;
2533 unsigned long nb_chan = 0;
2534 struct ltt_kernel_session *ksession;
2535 struct ltt_ust_session *usess;
2536
2537 assert(session);
2538
2539 /* Ease our life a bit ;) */
2540 ksession = session->kernel_session;
2541 usess = session->ust_session;
2542
2543 /* Is the session already started? */
2544 if (session->active) {
2545 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2546 goto error;
2547 }
2548
2549 /*
2550 * Starting a session without channel is useless since after that it's not
2551 * possible to enable channel thus inform the client.
2552 */
2553 if (usess && usess->domain_global.channels) {
2554 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2555 }
2556 if (ksession) {
2557 nb_chan += ksession->channel_count;
2558 }
2559 if (!nb_chan) {
2560 ret = LTTNG_ERR_NO_CHANNEL;
2561 goto error;
2562 }
2563
2564 /*
2565 * Record the timestamp of the first time the session is started for
2566 * an eventual session rotation call.
2567 */
2568 if (!session->has_been_started) {
2569 session->current_chunk_start_ts = time(NULL);
2570 if (session->current_chunk_start_ts == (time_t) -1) {
2571 PERROR("Failed to retrieve the \"%s\" session's start time",
2572 session->name);
2573 ret = LTTNG_ERR_FATAL;
2574 goto error;
2575 }
2576 if (!session->snapshot_mode && session->output_traces) {
2577 ret = session_mkdir(session);
2578 if (ret) {
2579 ERR("Failed to create the session directories");
2580 ret = LTTNG_ERR_CREATE_DIR_FAIL;
2581 goto error;
2582 }
2583 }
2584 }
2585
2586 /* Kernel tracing */
2587 if (ksession != NULL) {
2588 DBG("Start kernel tracing session %s", session->name);
2589 ret = start_kernel_session(ksession, kernel_tracer_fd);
2590 if (ret != LTTNG_OK) {
2591 goto error;
2592 }
2593 }
2594
2595 /* Flag session that trace should start automatically */
2596 if (usess) {
2597 /*
2598 * Even though the start trace might fail, flag this session active so
2599 * other application coming in are started by default.
2600 */
2601 usess->active = 1;
2602
2603 ret = ust_app_start_trace_all(usess);
2604 if (ret < 0) {
2605 ret = LTTNG_ERR_UST_START_FAIL;
2606 goto error;
2607 }
2608 }
2609
2610 /* Flag this after a successful start. */
2611 session->has_been_started = 1;
2612 session->active = 1;
2613
2614 /*
2615 * Clear the flag that indicates that a rotation was done while the
2616 * session was stopped.
2617 */
2618 session->rotated_after_last_stop = false;
2619
2620 if (session->rotate_timer_period) {
2621 ret = sessiond_rotate_timer_start(session,
2622 session->rotate_timer_period);
2623 if (ret < 0) {
2624 ERR("Failed to enable rotate timer");
2625 ret = LTTNG_ERR_UNK;
2626 goto error;
2627 }
2628 }
2629
2630 ret = LTTNG_OK;
2631
2632 error:
2633 return ret;
2634 }
2635
2636 static
2637 int rename_active_chunk(struct ltt_session *session)
2638 {
2639 int ret;
2640
2641 session->current_archive_id++;
2642
2643 /*
2644 * The currently active tracing path is now the folder we
2645 * want to rename.
2646 */
2647 ret = lttng_strncpy(session->rotation_chunk.current_rotate_path,
2648 session->rotation_chunk.active_tracing_path,
2649 sizeof(session->rotation_chunk.current_rotate_path));
2650 if (ret) {
2651 ERR("Failed to copy active tracing path");
2652 goto end;
2653 }
2654
2655 ret = rename_complete_chunk(session, time(NULL));
2656 if (ret < 0) {
2657 ERR("Failed to rename current rotate path");
2658 goto end;
2659 }
2660
2661 /*
2662 * We just renamed, the folder, we didn't do an actual rotation, so
2663 * the active tracing path is now the renamed folder and we have to
2664 * restore the rotate count.
2665 */
2666 ret = lttng_strncpy(session->rotation_chunk.active_tracing_path,
2667 session->rotation_chunk.current_rotate_path,
2668 sizeof(session->rotation_chunk.active_tracing_path));
2669 if (ret) {
2670 ERR("Failed to rename active session chunk tracing path");
2671 goto end;
2672 }
2673 end:
2674 session->current_archive_id--;
2675 return ret;
2676 }
2677
2678 /*
2679 * Command LTTNG_STOP_TRACE processed by the client thread.
2680 */
2681 int cmd_stop_trace(struct ltt_session *session)
2682 {
2683 int ret;
2684 struct ltt_kernel_channel *kchan;
2685 struct ltt_kernel_session *ksession;
2686 struct ltt_ust_session *usess;
2687 bool error_occured = false;
2688
2689 assert(session);
2690
2691 DBG("Begin stop session %s (id %" PRIu64 ")", session->name, session->id);
2692 /* Short cut */
2693 ksession = session->kernel_session;
2694 usess = session->ust_session;
2695
2696 /* Session is not active. Skip everythong and inform the client. */
2697 if (!session->active) {
2698 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2699 goto error;
2700 }
2701
2702 if (session->rotate_relay_pending_timer_enabled) {
2703 sessiond_timer_rotate_pending_stop(session);
2704 }
2705
2706 if (session->rotate_timer_enabled) {
2707 sessiond_rotate_timer_stop(session);
2708 }
2709
2710 if (session->current_archive_id > 0 && !session->rotate_pending) {
2711 ret = rename_active_chunk(session);
2712 if (ret) {
2713 /*
2714 * This error should not prevent the user from stopping
2715 * the session. However, it will be reported at the end.
2716 */
2717 error_occured = true;
2718 }
2719 }
2720
2721 /* Kernel tracer */
2722 if (ksession && ksession->active) {
2723 DBG("Stop kernel tracing");
2724
2725 ret = kernel_stop_session(ksession);
2726 if (ret < 0) {
2727 ret = LTTNG_ERR_KERN_STOP_FAIL;
2728 goto error;
2729 }
2730
2731 kernel_wait_quiescent(kernel_tracer_fd);
2732
2733 /* Flush metadata after stopping (if exists) */
2734 if (ksession->metadata_stream_fd >= 0) {
2735 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2736 if (ret < 0) {
2737 ERR("Kernel metadata flush failed");
2738 }
2739 }
2740
2741 /* Flush all buffers after stopping */
2742 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2743 ret = kernel_flush_buffer(kchan);
2744 if (ret < 0) {
2745 ERR("Kernel flush buffer error");
2746 }
2747 }
2748
2749 ksession->active = 0;
2750 DBG("Kernel session stopped %s (id %" PRIu64 ")", session->name,
2751 session->id);
2752 }
2753
2754 if (usess && usess->active) {
2755 /*
2756 * Even though the stop trace might fail, flag this session inactive so
2757 * other application coming in are not started by default.
2758 */
2759 usess->active = 0;
2760
2761 ret = ust_app_stop_trace_all(usess);
2762 if (ret < 0) {
2763 ret = LTTNG_ERR_UST_STOP_FAIL;
2764 goto error;
2765 }
2766 }
2767
2768 /* Flag inactive after a successful stop. */
2769 session->active = 0;
2770 ret = !error_occured ? LTTNG_OK : LTTNG_ERR_UNK;
2771
2772 error:
2773 return ret;
2774 }
2775
2776 /*
2777 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2778 */
2779 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2780 struct lttng_uri *uris)
2781 {
2782 int ret, i;
2783 struct ltt_kernel_session *ksess = session->kernel_session;
2784 struct ltt_ust_session *usess = session->ust_session;
2785
2786 assert(session);
2787 assert(uris);
2788 assert(nb_uri > 0);
2789
2790 /* Can't set consumer URI if the session is active. */
2791 if (session->active) {
2792 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2793 goto error;
2794 }
2795
2796 /* Set the "global" consumer URIs */
2797 for (i = 0; i < nb_uri; i++) {
2798 ret = add_uri_to_consumer(session->consumer,
2799 &uris[i], 0, session->name);
2800 if (ret != LTTNG_OK) {
2801 goto error;
2802 }
2803 }
2804
2805 /* Set UST session URIs */
2806 if (session->ust_session) {
2807 for (i = 0; i < nb_uri; i++) {
2808 ret = add_uri_to_consumer(
2809 session->ust_session->consumer,
2810 &uris[i], LTTNG_DOMAIN_UST,
2811 session->name);
2812 if (ret != LTTNG_OK) {
2813 goto error;
2814 }
2815 }
2816 }
2817
2818 /* Set kernel session URIs */
2819 if (session->kernel_session) {
2820 for (i = 0; i < nb_uri; i++) {
2821 ret = add_uri_to_consumer(
2822 session->kernel_session->consumer,
2823 &uris[i], LTTNG_DOMAIN_KERNEL,
2824 session->name);
2825 if (ret != LTTNG_OK) {
2826 goto error;
2827 }
2828 }
2829 }
2830
2831 /*
2832 * Make sure to set the session in output mode after we set URI since a
2833 * session can be created without URL (thus flagged in no output mode).
2834 */
2835 session->output_traces = 1;
2836 if (ksess) {
2837 ksess->output_traces = 1;
2838 }
2839
2840 if (usess) {
2841 usess->output_traces = 1;
2842 }
2843
2844 /* All good! */
2845 ret = LTTNG_OK;
2846
2847 error:
2848 return ret;
2849 }
2850
2851 /*
2852 * Command LTTNG_CREATE_SESSION processed by the client thread.
2853 */
2854 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
2855 size_t nb_uri, lttng_sock_cred *creds, unsigned int live_timer)
2856 {
2857 int ret;
2858 struct ltt_session *session;
2859
2860 assert(name);
2861 assert(creds);
2862
2863 /*
2864 * Verify if the session already exist
2865 *
2866 * XXX: There is no need for the session lock list here since the caller
2867 * (process_client_msg) is holding it. We might want to change that so a
2868 * single command does not lock the entire session list.
2869 */
2870 session = session_find_by_name(name);
2871 if (session != NULL) {
2872 ret = LTTNG_ERR_EXIST_SESS;
2873 goto find_error;
2874 }
2875
2876 /* Create tracing session in the registry */
2877 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
2878 LTTNG_SOCK_GET_GID_CRED(creds));
2879 if (ret != LTTNG_OK) {
2880 goto session_error;
2881 }
2882
2883 /*
2884 * Get the newly created session pointer back
2885 *
2886 * XXX: There is no need for the session lock list here since the caller
2887 * (process_client_msg) is holding it. We might want to change that so a
2888 * single command does not lock the entire session list.
2889 */
2890 session = session_find_by_name(name);
2891 assert(session);
2892
2893 session->live_timer = live_timer;
2894 /* Create default consumer output for the session not yet created. */
2895 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
2896 if (session->consumer == NULL) {
2897 ret = LTTNG_ERR_FATAL;
2898 goto consumer_error;
2899 }
2900
2901 if (uris) {
2902 ret = cmd_set_consumer_uri(session, nb_uri, uris);
2903 if (ret != LTTNG_OK) {
2904 goto consumer_error;
2905 }
2906 session->output_traces = 1;
2907 } else {
2908 session->output_traces = 0;
2909 DBG2("Session %s created with no output", session->name);
2910 }
2911
2912 session->consumer->enabled = 1;
2913
2914 return LTTNG_OK;
2915
2916 consumer_error:
2917 session_destroy(session);
2918 session_error:
2919 find_error:
2920 return ret;
2921 }
2922
2923 /*
2924 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
2925 */
2926 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
2927 size_t nb_uri, lttng_sock_cred *creds)
2928 {
2929 int ret;
2930 struct ltt_session *session;
2931 struct snapshot_output *new_output = NULL;
2932
2933 assert(name);
2934 assert(creds);
2935
2936 /*
2937 * Create session in no output mode with URIs set to NULL. The uris we've
2938 * received are for a default snapshot output if one.
2939 */
2940 ret = cmd_create_session_uri(name, NULL, 0, creds, 0);
2941 if (ret != LTTNG_OK) {
2942 goto error;
2943 }
2944
2945 /* Get the newly created session pointer back. This should NEVER fail. */
2946 session = session_find_by_name(name);
2947 assert(session);
2948
2949 /* Flag session for snapshot mode. */
2950 session->snapshot_mode = 1;
2951
2952 /* Skip snapshot output creation if no URI is given. */
2953 if (nb_uri == 0) {
2954 goto end;
2955 }
2956
2957 new_output = snapshot_output_alloc();
2958 if (!new_output) {
2959 ret = LTTNG_ERR_NOMEM;
2960 goto error_snapshot_alloc;
2961 }
2962
2963 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
2964 uris, nb_uri, session->consumer, new_output, &session->snapshot);
2965 if (ret < 0) {
2966 if (ret == -ENOMEM) {
2967 ret = LTTNG_ERR_NOMEM;
2968 } else {
2969 ret = LTTNG_ERR_INVALID;
2970 }
2971 goto error_snapshot;
2972 }
2973
2974 rcu_read_lock();
2975 snapshot_add_output(&session->snapshot, new_output);
2976 rcu_read_unlock();
2977
2978 end:
2979 return LTTNG_OK;
2980
2981 error_snapshot:
2982 snapshot_output_destroy(new_output);
2983 error_snapshot_alloc:
2984 session_destroy(session);
2985 error:
2986 return ret;
2987 }
2988
2989 /*
2990 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2991 *
2992 * Called with session lock held.
2993 */
2994 int cmd_destroy_session(struct ltt_session *session, int wpipe,
2995 struct notification_thread_handle *notification_thread_handle)
2996 {
2997 int ret;
2998 struct ltt_ust_session *usess;
2999 struct ltt_kernel_session *ksess;
3000
3001 /* Safety net */
3002 assert(session);
3003
3004 usess = session->ust_session;
3005 ksess = session->kernel_session;
3006
3007 DBG("Begin destroy session %s (id %" PRIu64 ")", session->name, session->id);
3008
3009 if (session->rotate_relay_pending_timer_enabled) {
3010 sessiond_timer_rotate_pending_stop(session);
3011 }
3012
3013 if (session->rotate_timer_enabled) {
3014 sessiond_rotate_timer_stop(session);
3015 }
3016
3017 if (session->rotate_size) {
3018 unsubscribe_session_consumed_size_rotation(session, notification_thread_handle);
3019 session->rotate_size = 0;
3020 }
3021
3022 /*
3023 * The rename of the current chunk is performed at stop, but if we rotated
3024 * the session after the previous stop command, we need to rename the
3025 * new (and empty) chunk that was started in between.
3026 */
3027 if (session->rotated_after_last_stop) {
3028 rename_active_chunk(session);
3029 }
3030
3031 /* Clean kernel session teardown */
3032 kernel_destroy_session(ksess);
3033
3034 /* UST session teardown */
3035 if (usess) {
3036 /* Close any relayd session */
3037 consumer_output_send_destroy_relayd(usess->consumer);
3038
3039 /* Destroy every UST application related to this session. */
3040 ret = ust_app_destroy_trace_all(usess);
3041 if (ret) {
3042 ERR("Error in ust_app_destroy_trace_all");
3043 }
3044
3045 /* Clean up the rest. */
3046 trace_ust_destroy_session(usess);
3047 }
3048
3049 /*
3050 * Must notify the kernel thread here to update it's poll set in order to
3051 * remove the channel(s)' fd just destroyed.
3052 */
3053 ret = notify_thread_pipe(wpipe);
3054 if (ret < 0) {
3055 PERROR("write kernel poll pipe");
3056 }
3057
3058 if (session->shm_path[0]) {
3059 /*
3060 * When a session is created with an explicit shm_path,
3061 * the consumer daemon will create its shared memory files
3062 * at that location and will *not* unlink them. This is normal
3063 * as the intention of that feature is to make it possible
3064 * to retrieve the content of those files should a crash occur.
3065 *
3066 * To ensure the content of those files can be used, the
3067 * sessiond daemon will replicate the content of the metadata
3068 * cache in a metadata file.
3069 *
3070 * On clean-up, it is expected that the consumer daemon will
3071 * unlink the shared memory files and that the session daemon
3072 * will unlink the metadata file. Then, the session's directory
3073 * in the shm path can be removed.
3074 *
3075 * Unfortunately, a flaw in the design of the sessiond's and
3076 * consumerd's tear down of channels makes it impossible to
3077 * determine when the sessiond _and_ the consumerd have both
3078 * destroyed their representation of a channel. For one, the
3079 * unlinking, close, and rmdir happen in deferred 'call_rcu'
3080 * callbacks in both daemons.
3081 *
3082 * However, it is also impossible for the sessiond to know when
3083 * the consumer daemon is done destroying its channel(s) since
3084 * it occurs as a reaction to the closing of the channel's file
3085 * descriptor. There is no resulting communication initiated
3086 * from the consumerd to the sessiond to confirm that the
3087 * operation is completed (and was successful).
3088 *
3089 * Until this is all fixed, the session daemon checks for the
3090 * removal of the session's shm path which makes it possible
3091 * to safely advertise a session as having been destroyed.
3092 *
3093 * Prior to this fix, it was not possible to reliably save
3094 * a session making use of the --shm-path option, destroy it,
3095 * and load it again. This is because the creation of the
3096 * session would fail upon seeing the session's shm path
3097 * already in existence.
3098 *
3099 * Note that none of the error paths in the check for the
3100 * directory's existence return an error. This is normal
3101 * as there isn't much that can be done. The session will
3102 * be destroyed properly, except that we can't offer the
3103 * guarantee that the same session can be re-created.
3104 */
3105 current_completion_handler = &destroy_completion_handler.handler;
3106 ret = lttng_strncpy(destroy_completion_handler.shm_path,
3107 session->shm_path,
3108 sizeof(destroy_completion_handler.shm_path));
3109 assert(!ret);
3110 }
3111 ret = session_destroy(session);
3112
3113 return ret;
3114 }
3115
3116 /*
3117 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3118 */
3119 int cmd_register_consumer(struct ltt_session *session,
3120 enum lttng_domain_type domain, const char *sock_path,
3121 struct consumer_data *cdata)
3122 {
3123 int ret, sock;
3124 struct consumer_socket *socket = NULL;
3125
3126 assert(session);
3127 assert(cdata);
3128 assert(sock_path);
3129
3130 switch (domain) {
3131 case LTTNG_DOMAIN_KERNEL:
3132 {
3133 struct ltt_kernel_session *ksess = session->kernel_session;
3134
3135 assert(ksess);
3136
3137 /* Can't register a consumer if there is already one */
3138 if (ksess->consumer_fds_sent != 0) {
3139 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
3140 goto error;
3141 }
3142
3143 sock = lttcomm_connect_unix_sock(sock_path);
3144 if (sock < 0) {
3145 ret = LTTNG_ERR_CONNECT_FAIL;
3146 goto error;
3147 }
3148 cdata->cmd_sock = sock;
3149
3150 socket = consumer_allocate_socket(&cdata->cmd_sock);
3151 if (socket == NULL) {
3152 ret = close(sock);
3153 if (ret < 0) {
3154 PERROR("close register consumer");
3155 }
3156 cdata->cmd_sock = -1;
3157 ret = LTTNG_ERR_FATAL;
3158 goto error;
3159 }
3160
3161 socket->lock = zmalloc(sizeof(pthread_mutex_t));
3162 if (socket->lock == NULL) {
3163 PERROR("zmalloc pthread mutex");
3164 ret = LTTNG_ERR_FATAL;
3165 goto error;
3166 }
3167 pthread_mutex_init(socket->lock, NULL);
3168 socket->registered = 1;
3169
3170 rcu_read_lock();
3171 consumer_add_socket(socket, ksess->consumer);
3172 rcu_read_unlock();
3173
3174 pthread_mutex_lock(&cdata->pid_mutex);
3175 cdata->pid = -1;
3176 pthread_mutex_unlock(&cdata->pid_mutex);
3177
3178 break;
3179 }
3180 default:
3181 /* TODO: Userspace tracing */
3182 ret = LTTNG_ERR_UND;
3183 goto error;
3184 }
3185
3186 return LTTNG_OK;
3187
3188 error:
3189 if (socket) {
3190 consumer_destroy_socket(socket);
3191 }
3192 return ret;
3193 }
3194
3195 /*
3196 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3197 */
3198 ssize_t cmd_list_domains(struct ltt_session *session,
3199 struct lttng_domain **domains)
3200 {
3201 int ret, index = 0;
3202 ssize_t nb_dom = 0;
3203 struct agent *agt;
3204 struct lttng_ht_iter iter;
3205
3206 if (session->kernel_session != NULL) {
3207 DBG3("Listing domains found kernel domain");
3208 nb_dom++;
3209 }
3210
3211 if (session->ust_session != NULL) {
3212 DBG3("Listing domains found UST global domain");
3213 nb_dom++;
3214
3215 rcu_read_lock();
3216 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3217 agt, node.node) {
3218 if (agt->being_used) {
3219 nb_dom++;
3220 }
3221 }
3222 rcu_read_unlock();
3223 }
3224
3225 if (!nb_dom) {
3226 goto end;
3227 }
3228
3229 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3230 if (*domains == NULL) {
3231 ret = LTTNG_ERR_FATAL;
3232 goto error;
3233 }
3234
3235 if (session->kernel_session != NULL) {
3236 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3237
3238 /* Kernel session buffer type is always GLOBAL */
3239 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
3240
3241 index++;
3242 }
3243
3244 if (session->ust_session != NULL) {
3245 (*domains)[index].type = LTTNG_DOMAIN_UST;
3246 (*domains)[index].buf_type = session->ust_session->buffer_type;
3247 index++;
3248
3249 rcu_read_lock();
3250 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
3251 agt, node.node) {
3252 if (agt->being_used) {
3253 (*domains)[index].type = agt->domain;
3254 (*domains)[index].buf_type = session->ust_session->buffer_type;
3255 index++;
3256 }
3257 }
3258 rcu_read_unlock();
3259 }
3260 end:
3261 return nb_dom;
3262
3263 error:
3264 /* Return negative value to differentiate return code */
3265 return -ret;
3266 }
3267
3268
3269 /*
3270 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3271 */
3272 ssize_t cmd_list_channels(enum lttng_domain_type domain,
3273 struct ltt_session *session, struct lttng_channel **channels)
3274 {
3275 ssize_t nb_chan = 0, payload_size = 0, ret;
3276
3277 switch (domain) {
3278 case LTTNG_DOMAIN_KERNEL:
3279 if (session->kernel_session != NULL) {
3280 nb_chan = session->kernel_session->channel_count;
3281 }
3282 DBG3("Number of kernel channels %zd", nb_chan);
3283 if (nb_chan <= 0) {
3284 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
3285 goto end;
3286 }
3287 break;
3288 case LTTNG_DOMAIN_UST:
3289 if (session->ust_session != NULL) {
3290 rcu_read_lock();
3291 nb_chan = lttng_ht_get_count(
3292 session->ust_session->domain_global.channels);
3293 rcu_read_unlock();
3294 }
3295 DBG3("Number of UST global channels %zd", nb_chan);
3296 if (nb_chan < 0) {
3297 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
3298 goto end;
3299 }
3300 break;
3301 default:
3302 ret = -LTTNG_ERR_UND;
3303 goto end;
3304 }
3305
3306 if (nb_chan > 0) {
3307 const size_t channel_size = sizeof(struct lttng_channel) +
3308 sizeof(struct lttng_channel_extended);
3309 struct lttng_channel_extended *channel_exts;
3310
3311 payload_size = nb_chan * channel_size;
3312 *channels = zmalloc(payload_size);
3313 if (*channels == NULL) {
3314 ret = -LTTNG_ERR_FATAL;
3315 goto end;
3316 }
3317
3318 channel_exts = ((void *) *channels) +
3319 (nb_chan * sizeof(struct lttng_channel));
3320 ret = list_lttng_channels(domain, session, *channels, channel_exts);
3321 if (ret != LTTNG_OK) {
3322 free(*channels);
3323 *channels = NULL;
3324 goto end;
3325 }
3326 } else {
3327 *channels = NULL;
3328 }
3329
3330 ret = payload_size;
3331 end:
3332 return ret;
3333 }
3334
3335 /*
3336 * Command LTTNG_LIST_EVENTS processed by the client thread.
3337 */
3338 ssize_t cmd_list_events(enum lttng_domain_type domain,
3339 struct ltt_session *session, char *channel_name,
3340 struct lttng_event **events, size_t *total_size)
3341 {
3342 int ret = 0;
3343 ssize_t nb_event = 0;
3344
3345 switch (domain) {
3346 case LTTNG_DOMAIN_KERNEL:
3347 if (session->kernel_session != NULL) {
3348 nb_event = list_lttng_kernel_events(channel_name,
3349 session->kernel_session, events,
3350 total_size);
3351 }
3352 break;
3353 case LTTNG_DOMAIN_UST:
3354 {
3355 if (session->ust_session != NULL) {
3356 nb_event = list_lttng_ust_global_events(channel_name,
3357 &session->ust_session->domain_global, events,
3358 total_size);
3359 }
3360 break;
3361 }
3362 case LTTNG_DOMAIN_LOG4J:
3363 case LTTNG_DOMAIN_JUL:
3364 case LTTNG_DOMAIN_PYTHON:
3365 if (session->ust_session) {
3366 struct lttng_ht_iter iter;
3367 struct agent *agt;
3368
3369 rcu_read_lock();
3370 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3371 &iter.iter, agt, node.node) {
3372 if (agt->domain == domain) {
3373 nb_event = list_lttng_agent_events(
3374 agt, events,
3375 total_size);
3376 break;
3377 }
3378 }
3379 rcu_read_unlock();
3380 }
3381 break;
3382 default:
3383 ret = LTTNG_ERR_UND;
3384 goto error;
3385 }
3386
3387 return nb_event;
3388
3389 error:
3390 /* Return negative value to differentiate return code */
3391 return -ret;
3392 }
3393
3394 /*
3395 * Using the session list, filled a lttng_session array to send back to the
3396 * client for session listing.
3397 *
3398 * The session list lock MUST be acquired before calling this function. Use
3399 * session_lock_list() and session_unlock_list().
3400 */
3401 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
3402 gid_t gid)
3403 {
3404 int ret;
3405 unsigned int i = 0;
3406 struct ltt_session *session;
3407 struct ltt_session_list *list = session_get_list();
3408
3409 DBG("Getting all available session for UID %d GID %d",
3410 uid, gid);
3411 /*
3412 * Iterate over session list and append data after the control struct in
3413 * the buffer.
3414 */
3415 cds_list_for_each_entry(session, &list->head, list) {
3416 /*
3417 * Only list the sessions the user can control.
3418 */
3419 if (!session_access_ok(session, uid, gid)) {
3420 continue;
3421 }
3422
3423 struct ltt_kernel_session *ksess = session->kernel_session;
3424 struct ltt_ust_session *usess = session->ust_session;
3425
3426 if (session->consumer->type == CONSUMER_DST_NET ||
3427 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3428 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3429 ret = build_network_session_path(sessions[i].path,
3430 sizeof(sessions[i].path), session);
3431 } else {
3432 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3433 session->consumer->dst.session_root_path);
3434 }
3435 if (ret < 0) {
3436 PERROR("snprintf session path");
3437 continue;
3438 }
3439
3440 strncpy(sessions[i].name, session->name, NAME_MAX);
3441 sessions[i].name[NAME_MAX - 1] = '\0';
3442 sessions[i].enabled = session->active;
3443 sessions[i].snapshot_mode = session->snapshot_mode;
3444 sessions[i].live_timer_interval = session->live_timer;
3445 i++;
3446 }
3447 }
3448
3449 /*
3450 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3451 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3452 */
3453 int cmd_data_pending(struct ltt_session *session)
3454 {
3455 int ret;
3456 struct ltt_kernel_session *ksess = session->kernel_session;
3457 struct ltt_ust_session *usess = session->ust_session;
3458
3459 assert(session);
3460
3461 DBG("Data pending for session %s", session->name);
3462
3463 /* Session MUST be stopped to ask for data availability. */
3464 if (session->active) {
3465 ret = LTTNG_ERR_SESSION_STARTED;
3466 goto error;
3467 } else {
3468 /*
3469 * If stopped, just make sure we've started before else the above call
3470 * will always send that there is data pending.
3471 *
3472 * The consumer assumes that when the data pending command is received,
3473 * the trace has been started before or else no output data is written
3474 * by the streams which is a condition for data pending. So, this is
3475 * *VERY* important that we don't ask the consumer before a start
3476 * trace.
3477 */
3478 if (!session->has_been_started) {
3479 ret = 0;
3480 goto error;
3481 }
3482 }
3483
3484 /*
3485 * A rotation is still pending, we have to wait.
3486 */
3487 if (session->rotate_pending) {
3488 DBG("Rotate still pending for session %s", session->name);
3489 ret = 1;
3490 goto error;
3491 }
3492
3493 if (ksess && ksess->consumer) {
3494 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3495 if (ret == 1) {
3496 /* Data is still being extracted for the kernel. */
3497 goto error;
3498 }
3499 }
3500
3501 if (usess && usess->consumer) {
3502 ret = consumer_is_data_pending(usess->id, usess->consumer);
3503 if (ret == 1) {
3504 /* Data is still being extracted for the kernel. */
3505 goto error;
3506 }
3507 }
3508
3509 /* Data is ready to be read by a viewer */
3510 ret = 0;
3511
3512 error:
3513 return ret;
3514 }
3515
3516 /*
3517 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3518 *
3519 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3520 */
3521 int cmd_snapshot_add_output(struct ltt_session *session,
3522 struct lttng_snapshot_output *output, uint32_t *id)
3523 {
3524 int ret;
3525 struct snapshot_output *new_output;
3526
3527 assert(session);
3528 assert(output);
3529
3530 DBG("Cmd snapshot add output for session %s", session->name);
3531
3532 /*
3533 * Can't create an output if the session is not set in no-output mode.
3534 */
3535 if (session->output_traces) {
3536 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3537 goto error;
3538 }
3539
3540 /* Only one output is allowed until we have the "tee" feature. */
3541 if (session->snapshot.nb_output == 1) {
3542 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3543 goto error;
3544 }
3545
3546 new_output = snapshot_output_alloc();
3547 if (!new_output) {
3548 ret = LTTNG_ERR_NOMEM;
3549 goto error;
3550 }
3551
3552 ret = snapshot_output_init(output->max_size, output->name,
3553 output->ctrl_url, output->data_url, session->consumer, new_output,
3554 &session->snapshot);
3555 if (ret < 0) {
3556 if (ret == -ENOMEM) {
3557 ret = LTTNG_ERR_NOMEM;
3558 } else {
3559 ret = LTTNG_ERR_INVALID;
3560 }
3561 goto free_error;
3562 }
3563
3564 rcu_read_lock();
3565 snapshot_add_output(&session->snapshot, new_output);
3566 if (id) {
3567 *id = new_output->id;
3568 }
3569 rcu_read_unlock();
3570
3571 return LTTNG_OK;
3572
3573 free_error:
3574 snapshot_output_destroy(new_output);
3575 error:
3576 return ret;
3577 }
3578
3579 /*
3580 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3581 *
3582 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3583 */
3584 int cmd_snapshot_del_output(struct ltt_session *session,
3585 struct lttng_snapshot_output *output)
3586 {
3587 int ret;
3588 struct snapshot_output *sout = NULL;
3589
3590 assert(session);
3591 assert(output);
3592
3593 rcu_read_lock();
3594
3595 /*
3596 * Permission denied to create an output if the session is not
3597 * set in no output mode.
3598 */
3599 if (session->output_traces) {
3600 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3601 goto error;
3602 }
3603
3604 if (output->id) {
3605 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
3606 session->name);
3607 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
3608 } else if (*output->name != '\0') {
3609 DBG("Cmd snapshot del output name %s for session %s", output->name,
3610 session->name);
3611 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
3612 }
3613 if (!sout) {
3614 ret = LTTNG_ERR_INVALID;
3615 goto error;
3616 }
3617
3618 snapshot_delete_output(&session->snapshot, sout);
3619 snapshot_output_destroy(sout);
3620 ret = LTTNG_OK;
3621
3622 error:
3623 rcu_read_unlock();
3624 return ret;
3625 }
3626
3627 /*
3628 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
3629 *
3630 * If no output is available, outputs is untouched and 0 is returned.
3631 *
3632 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
3633 */
3634 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
3635 struct lttng_snapshot_output **outputs)
3636 {
3637 int ret, idx = 0;
3638 struct lttng_snapshot_output *list = NULL;
3639 struct lttng_ht_iter iter;
3640 struct snapshot_output *output;
3641
3642 assert(session);
3643 assert(outputs);
3644
3645 DBG("Cmd snapshot list outputs for session %s", session->name);
3646
3647 /*
3648 * Permission denied to create an output if the session is not
3649 * set in no output mode.
3650 */
3651 if (session->output_traces) {
3652 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3653 goto end;
3654 }
3655
3656 if (session->snapshot.nb_output == 0) {
3657 ret = 0;
3658 goto end;
3659 }
3660
3661 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
3662 if (!list) {
3663 ret = -LTTNG_ERR_NOMEM;
3664 goto end;
3665 }
3666
3667 /* Copy list from session to the new list object. */
3668 rcu_read_lock();
3669 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
3670 output, node.node) {
3671 assert(output->consumer);
3672 list[idx].id = output->id;
3673 list[idx].max_size = output->max_size;
3674 if (lttng_strncpy(list[idx].name, output->name,
3675 sizeof(list[idx].name))) {
3676 ret = -LTTNG_ERR_INVALID;
3677 goto error;
3678 }
3679 if (output->consumer->type == CONSUMER_DST_LOCAL) {
3680 if (lttng_strncpy(list[idx].ctrl_url,
3681 output->consumer->dst.session_root_path,
3682 sizeof(list[idx].ctrl_url))) {
3683 ret = -LTTNG_ERR_INVALID;
3684 goto error;
3685 }
3686 } else {
3687 /* Control URI. */
3688 ret = uri_to_str_url(&output->consumer->dst.net.control,
3689 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
3690 if (ret < 0) {
3691 ret = -LTTNG_ERR_NOMEM;
3692 goto error;
3693 }
3694
3695 /* Data URI. */
3696 ret = uri_to_str_url(&output->consumer->dst.net.data,
3697 list[idx].data_url, sizeof(list[idx].data_url));
3698 if (ret < 0) {
3699 ret = -LTTNG_ERR_NOMEM;
3700 goto error;
3701 }
3702 }
3703 idx++;
3704 }
3705
3706 *outputs = list;
3707 list = NULL;
3708 ret = session->snapshot.nb_output;
3709 error:
3710 rcu_read_unlock();
3711 free(list);
3712 end:
3713 return ret;
3714 }
3715
3716 /*
3717 * Check if we can regenerate the metadata for this session.
3718 * Only kernel, UST per-uid and non-live sessions are supported.
3719 *
3720 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
3721 */
3722 static
3723 int check_regenerate_metadata_support(struct ltt_session *session)
3724 {
3725 int ret;
3726
3727 assert(session);
3728
3729 if (session->live_timer != 0) {
3730 ret = LTTNG_ERR_LIVE_SESSION;
3731 goto end;
3732 }
3733 if (!session->active) {
3734 ret = LTTNG_ERR_SESSION_NOT_STARTED;
3735 goto end;
3736 }
3737 if (session->ust_session) {
3738 switch (session->ust_session->buffer_type) {
3739 case LTTNG_BUFFER_PER_UID:
3740 break;
3741 case LTTNG_BUFFER_PER_PID:
3742 ret = LTTNG_ERR_PER_PID_SESSION;
3743 goto end;
3744 default:
3745 assert(0);
3746 ret = LTTNG_ERR_UNK;
3747 goto end;
3748 }
3749 }
3750 if (session->consumer->type == CONSUMER_DST_NET &&
3751 session->consumer->relay_minor_version < 8) {
3752 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
3753 goto end;
3754 }
3755 ret = 0;
3756
3757 end:
3758 return ret;
3759 }
3760
3761 static
3762 int clear_metadata_file(int fd)
3763 {
3764 int ret;
3765 off_t lseek_ret;
3766
3767 lseek_ret = lseek(fd, 0, SEEK_SET);
3768 if (lseek_ret < 0) {
3769 PERROR("lseek");
3770 ret = -1;
3771 goto end;
3772 }
3773
3774 ret = ftruncate(fd, 0);
3775 if (ret < 0) {
3776 PERROR("ftruncate");
3777 goto end;
3778 }
3779
3780 end:
3781 return ret;
3782 }
3783
3784 static
3785 int ust_regenerate_metadata(struct ltt_ust_session *usess)
3786 {
3787 int ret = 0;
3788 struct buffer_reg_uid *uid_reg = NULL;
3789 struct buffer_reg_session *session_reg = NULL;
3790
3791 rcu_read_lock();
3792 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
3793 struct ust_registry_session *registry;
3794 struct ust_registry_channel *chan;
3795 struct lttng_ht_iter iter_chan;
3796
3797 session_reg = uid_reg->registry;
3798 registry = session_reg->reg.ust;
3799
3800 pthread_mutex_lock(&registry->lock);
3801 registry->metadata_len_sent = 0;
3802 memset(registry->metadata, 0, registry->metadata_alloc_len);
3803 registry->metadata_len = 0;
3804 registry->metadata_version++;
3805 if (registry->metadata_fd > 0) {
3806 /* Clear the metadata file's content. */
3807 ret = clear_metadata_file(registry->metadata_fd);
3808 if (ret) {
3809 pthread_mutex_unlock(&registry->lock);
3810 goto end;
3811 }
3812 }
3813
3814 ret = ust_metadata_session_statedump(registry, NULL,
3815 registry->major, registry->minor);
3816 if (ret) {
3817 pthread_mutex_unlock(&registry->lock);
3818 ERR("Failed to generate session metadata (err = %d)",
3819 ret);
3820 goto end;
3821 }
3822 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
3823 chan, node.node) {
3824 struct ust_registry_event *event;
3825 struct lttng_ht_iter iter_event;
3826
3827 ret = ust_metadata_channel_statedump(registry, chan);
3828 if (ret) {
3829 pthread_mutex_unlock(&registry->lock);
3830 ERR("Failed to generate channel metadata "
3831 "(err = %d)", ret);
3832 goto end;
3833 }
3834 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
3835 event, node.node) {
3836 ret = ust_metadata_event_statedump(registry,
3837 chan, event);
3838 if (ret) {
3839 pthread_mutex_unlock(&registry->lock);
3840 ERR("Failed to generate event metadata "
3841 "(err = %d)", ret);
3842 goto end;
3843 }
3844 }
3845 }
3846 pthread_mutex_unlock(&registry->lock);
3847 }
3848
3849 end:
3850 rcu_read_unlock();
3851 return ret;
3852 }
3853
3854 /*
3855 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
3856 *
3857 * Ask the consumer to truncate the existing metadata file(s) and
3858 * then regenerate the metadata. Live and per-pid sessions are not
3859 * supported and return an error.
3860 *
3861 * Return 0 on success or else a LTTNG_ERR code.
3862 */
3863 int cmd_regenerate_metadata(struct ltt_session *session)
3864 {
3865 int ret;
3866
3867 assert(session);
3868
3869 ret = check_regenerate_metadata_support(session);
3870 if (ret) {
3871 goto end;
3872 }
3873
3874 if (session->kernel_session) {
3875 ret = kernctl_session_regenerate_metadata(
3876 session->kernel_session->fd);
3877 if (ret < 0) {
3878 ERR("Failed to regenerate the kernel metadata");
3879 goto end;
3880 }
3881 }
3882
3883 if (session->ust_session) {
3884 ret = ust_regenerate_metadata(session->ust_session);
3885 if (ret < 0) {
3886 ERR("Failed to regenerate the UST metadata");
3887 goto end;
3888 }
3889 }
3890 DBG("Cmd metadata regenerate for session %s", session->name);
3891 ret = LTTNG_OK;
3892
3893 end:
3894 return ret;
3895 }
3896
3897 /*
3898 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
3899 *
3900 * Ask the tracer to regenerate a new statedump.
3901 *
3902 * Return 0 on success or else a LTTNG_ERR code.
3903 */
3904 int cmd_regenerate_statedump(struct ltt_session *session)
3905 {
3906 int ret;
3907
3908 assert(session);
3909
3910 if (!session->active) {
3911 ret = LTTNG_ERR_SESSION_NOT_STARTED;
3912 goto end;
3913 }
3914
3915 if (session->kernel_session) {
3916 ret = kernctl_session_regenerate_statedump(
3917 session->kernel_session->fd);
3918 /*
3919 * Currently, the statedump in kernel can only fail if out
3920 * of memory.
3921 */
3922 if (ret < 0) {
3923 if (ret == -ENOMEM) {
3924 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
3925 } else {
3926 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
3927 }
3928 ERR("Failed to regenerate the kernel statedump");
3929 goto end;
3930 }
3931 }
3932
3933 if (session->ust_session) {
3934 ret = ust_app_regenerate_statedump_all(session->ust_session);
3935 /*
3936 * Currently, the statedump in UST always returns 0.
3937 */
3938 if (ret < 0) {
3939 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
3940 ERR("Failed to regenerate the UST statedump");
3941 goto end;
3942 }
3943 }
3944 DBG("Cmd regenerate statedump for session %s", session->name);
3945 ret = LTTNG_OK;
3946
3947 end:
3948 return ret;
3949 }
3950
3951 int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
3952 struct notification_thread_handle *notification_thread)
3953 {
3954 int ret;
3955 size_t trigger_len;
3956 ssize_t sock_recv_len;
3957 struct lttng_trigger *trigger = NULL;
3958 struct lttng_buffer_view view;
3959 struct lttng_dynamic_buffer trigger_buffer;
3960
3961 lttng_dynamic_buffer_init(&trigger_buffer);
3962 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
3963 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
3964 if (ret) {
3965 ret = LTTNG_ERR_NOMEM;
3966 goto end;
3967 }
3968
3969 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
3970 trigger_len);
3971 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
3972 ERR("Failed to receive \"register trigger\" command payload");
3973 /* TODO: should this be a new error enum ? */
3974 ret = LTTNG_ERR_INVALID_TRIGGER;
3975 goto end;
3976 }
3977
3978 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
3979 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
3980 trigger_len) {
3981 ERR("Invalid trigger payload received in \"register trigger\" command");
3982 ret = LTTNG_ERR_INVALID_TRIGGER;
3983 goto end;
3984 }
3985
3986 ret = notification_thread_command_register_trigger(notification_thread,
3987 trigger);
3988 /* Ownership of trigger was transferred. */
3989 trigger = NULL;
3990 end:
3991 lttng_trigger_destroy(trigger);
3992 lttng_dynamic_buffer_reset(&trigger_buffer);
3993 return ret;
3994 }
3995
3996 int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
3997 struct notification_thread_handle *notification_thread)
3998 {
3999 int ret;
4000 size_t trigger_len;
4001 ssize_t sock_recv_len;
4002 struct lttng_trigger *trigger = NULL;
4003 struct lttng_buffer_view view;
4004 struct lttng_dynamic_buffer trigger_buffer;
4005
4006 lttng_dynamic_buffer_init(&trigger_buffer);
4007 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
4008 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
4009 if (ret) {
4010 ret = LTTNG_ERR_NOMEM;
4011 goto end;
4012 }
4013
4014 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
4015 trigger_len);
4016 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
4017 ERR("Failed to receive \"unregister trigger\" command payload");
4018 /* TODO: should this be a new error enum ? */
4019 ret = LTTNG_ERR_INVALID_TRIGGER;
4020 goto end;
4021 }
4022
4023 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
4024 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
4025 trigger_len) {
4026 ERR("Invalid trigger payload received in \"unregister trigger\" command");
4027 ret = LTTNG_ERR_INVALID_TRIGGER;
4028 goto end;
4029 }
4030
4031 ret = notification_thread_command_unregister_trigger(notification_thread,
4032 trigger);
4033 end:
4034 lttng_trigger_destroy(trigger);
4035 lttng_dynamic_buffer_reset(&trigger_buffer);
4036 return ret;
4037 }
4038
4039 /*
4040 * Send relayd sockets from snapshot output to consumer. Ignore request if the
4041 * snapshot output is *not* set with a remote destination.
4042 *
4043 * Return 0 on success or a LTTNG_ERR code.
4044 */
4045 static int set_relayd_for_snapshot(struct consumer_output *consumer,
4046 struct snapshot_output *snap_output, struct ltt_session *session)
4047 {
4048 int ret = LTTNG_OK;
4049 struct lttng_ht_iter iter;
4050 struct consumer_socket *socket;
4051
4052 assert(consumer);
4053 assert(snap_output);
4054 assert(session);
4055
4056 DBG2("Set relayd object from snapshot output");
4057
4058 /* Ignore if snapshot consumer output is not network. */
4059 if (snap_output->consumer->type != CONSUMER_DST_NET) {
4060 goto error;
4061 }
4062
4063 /*
4064 * For each consumer socket, create and send the relayd object of the
4065 * snapshot output.
4066 */
4067 rcu_read_lock();
4068 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
4069 socket, node.node) {
4070 pthread_mutex_lock(socket->lock);
4071 ret = send_consumer_relayd_sockets(0, session->id,
4072 snap_output->consumer, socket,
4073 session->name, session->hostname,
4074 session->live_timer);
4075 pthread_mutex_unlock(socket->lock);
4076 if (ret != LTTNG_OK) {
4077 rcu_read_unlock();
4078 goto error;
4079 }
4080 }
4081 rcu_read_unlock();
4082
4083 error:
4084 return ret;
4085 }
4086
4087 /*
4088 * Record a kernel snapshot.
4089 *
4090 * Return LTTNG_OK on success or a LTTNG_ERR code.
4091 */
4092 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
4093 struct snapshot_output *output, struct ltt_session *session,
4094 int wait, uint64_t nb_packets_per_stream)
4095 {
4096 int ret;
4097
4098 assert(ksess);
4099 assert(output);
4100 assert(session);
4101
4102
4103 /*
4104 * Copy kernel session sockets so we can communicate with the right
4105 * consumer for the snapshot record command.
4106 */
4107 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
4108 if (ret < 0) {
4109 ret = LTTNG_ERR_NOMEM;
4110 goto error;
4111 }
4112
4113 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
4114 if (ret != LTTNG_OK) {
4115 goto error_snapshot;
4116 }
4117
4118 ret = kernel_snapshot_record(ksess, output, wait, nb_packets_per_stream);
4119 if (ret != LTTNG_OK) {
4120 goto error_snapshot;
4121 }
4122
4123 ret = LTTNG_OK;
4124 goto end;
4125
4126 error_snapshot:
4127 /* Clean up copied sockets so this output can use some other later on. */
4128 consumer_destroy_output_sockets(output->consumer);
4129 error:
4130 end:
4131 return ret;
4132 }
4133
4134 /*
4135 * Record a UST snapshot.
4136 *
4137 * Return 0 on success or a LTTNG_ERR error code.
4138 */
4139 static int record_ust_snapshot(struct ltt_ust_session *usess,
4140 struct snapshot_output *output, struct ltt_session *session,
4141 int wait, uint64_t nb_packets_per_stream)
4142 {
4143 int ret;
4144
4145 assert(usess);
4146 assert(output);
4147 assert(session);
4148
4149 /*
4150 * Copy UST session sockets so we can communicate with the right
4151 * consumer for the snapshot record command.
4152 */
4153 ret = consumer_copy_sockets(output->consumer, usess->consumer);
4154 if (ret < 0) {
4155 ret = LTTNG_ERR_NOMEM;
4156 goto error;
4157 }
4158
4159 ret = set_relayd_for_snapshot(usess->consumer, output, session);
4160 if (ret != LTTNG_OK) {
4161 goto error_snapshot;
4162 }
4163
4164 ret = ust_app_snapshot_record(usess, output, wait, nb_packets_per_stream);
4165 if (ret < 0) {
4166 switch (-ret) {
4167 case EINVAL:
4168 ret = LTTNG_ERR_INVALID;
4169 break;
4170 default:
4171 ret = LTTNG_ERR_SNAPSHOT_FAIL;
4172 break;
4173 }
4174 goto error_snapshot;
4175 }
4176
4177 ret = LTTNG_OK;
4178
4179 error_snapshot:
4180 /* Clean up copied sockets so this output can use some other later on. */
4181 consumer_destroy_output_sockets(output->consumer);
4182 error:
4183 return ret;
4184 }
4185
4186 static
4187 uint64_t get_session_size_one_more_packet_per_stream(struct ltt_session *session,
4188 uint64_t cur_nr_packets)
4189 {
4190 uint64_t tot_size = 0;
4191
4192 if (session->kernel_session) {
4193 struct ltt_kernel_channel *chan;
4194 struct ltt_kernel_session *ksess = session->kernel_session;
4195
4196 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
4197 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
4198 /*
4199 * Don't take channel into account if we
4200 * already grab all its packets.
4201 */
4202 continue;
4203 }
4204 tot_size += chan->channel->attr.subbuf_size
4205 * chan->stream_count;
4206 }
4207 }
4208
4209 if (session->ust_session) {
4210 struct ltt_ust_session *usess = session->ust_session;
4211
4212 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
4213 cur_nr_packets);
4214 }
4215
4216 return tot_size;
4217 }
4218
4219 /*
4220 * Calculate the number of packets we can grab from each stream that
4221 * fits within the overall snapshot max size.
4222 *
4223 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
4224 * the number of packets per stream.
4225 *
4226 * TODO: this approach is not perfect: we consider the worse case
4227 * (packet filling the sub-buffers) as an upper bound, but we could do
4228 * better if we do this calculation while we actually grab the packet
4229 * content: we would know how much padding we don't actually store into
4230 * the file.
4231 *
4232 * This algorithm is currently bounded by the number of packets per
4233 * stream.
4234 *
4235 * Since we call this algorithm before actually grabbing the data, it's
4236 * an approximation: for instance, applications could appear/disappear
4237 * in between this call and actually grabbing data.
4238 */
4239 static
4240 int64_t get_session_nb_packets_per_stream(struct ltt_session *session, uint64_t max_size)
4241 {
4242 int64_t size_left;
4243 uint64_t cur_nb_packets = 0;
4244
4245 if (!max_size) {
4246 return 0; /* Infinite */
4247 }
4248
4249 size_left = max_size;
4250 for (;;) {
4251 uint64_t one_more_packet_tot_size;
4252
4253 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(session,
4254 cur_nb_packets);
4255 if (!one_more_packet_tot_size) {
4256 /* We are already grabbing all packets. */
4257 break;
4258 }
4259 size_left -= one_more_packet_tot_size;
4260 if (size_left < 0) {
4261 break;
4262 }
4263 cur_nb_packets++;
4264 }
4265 if (!cur_nb_packets) {
4266 /* Not enough room to grab one packet of each stream, error. */
4267 return -1;
4268 }
4269 return cur_nb_packets;
4270 }
4271
4272 /*
4273 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
4274 *
4275 * The wait parameter is ignored so this call always wait for the snapshot to
4276 * complete before returning.
4277 *
4278 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4279 */
4280 int cmd_snapshot_record(struct ltt_session *session,
4281 struct lttng_snapshot_output *output, int wait)
4282 {
4283 int ret = LTTNG_OK;
4284 unsigned int use_tmp_output = 0;
4285 struct snapshot_output tmp_output;
4286 unsigned int snapshot_success = 0;
4287 char datetime[16];
4288
4289 assert(session);
4290 assert(output);
4291
4292 DBG("Cmd snapshot record for session %s", session->name);
4293
4294 /* Get the datetime for the snapshot output directory. */
4295 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
4296 sizeof(datetime));
4297 if (!ret) {
4298 ret = LTTNG_ERR_INVALID;
4299 goto error;
4300 }
4301
4302 /*
4303 * Permission denied to create an output if the session is not
4304 * set in no output mode.
4305 */
4306 if (session->output_traces) {
4307 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
4308 goto error;
4309 }
4310
4311 /* The session needs to be started at least once. */
4312 if (!session->has_been_started) {
4313 ret = LTTNG_ERR_START_SESSION_ONCE;
4314 goto error;
4315 }
4316
4317 /* Use temporary output for the session. */
4318 if (*output->ctrl_url != '\0') {
4319 ret = snapshot_output_init(output->max_size, output->name,
4320 output->ctrl_url, output->data_url, session->consumer,
4321 &tmp_output, NULL);
4322 if (ret < 0) {
4323 if (ret == -ENOMEM) {
4324 ret = LTTNG_ERR_NOMEM;
4325 } else {
4326 ret = LTTNG_ERR_INVALID;
4327 }
4328 goto error;
4329 }
4330 /* Use the global session count for the temporary snapshot. */
4331 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
4332
4333 /* Use the global datetime */
4334 memcpy(tmp_output.datetime, datetime, sizeof(datetime));
4335 use_tmp_output = 1;
4336 }
4337
4338 if (use_tmp_output) {
4339 int64_t nb_packets_per_stream;
4340
4341 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
4342 tmp_output.max_size);
4343 if (nb_packets_per_stream < 0) {
4344 ret = LTTNG_ERR_MAX_SIZE_INVALID;
4345 goto error;
4346 }
4347
4348 if (session->kernel_session) {
4349 ret = record_kernel_snapshot(session->kernel_session,
4350 &tmp_output, session,
4351 wait, nb_packets_per_stream);
4352 if (ret != LTTNG_OK) {
4353 goto error;
4354 }
4355 }
4356
4357 if (session->ust_session) {
4358 ret = record_ust_snapshot(session->ust_session,
4359 &tmp_output, session,
4360 wait, nb_packets_per_stream);
4361 if (ret != LTTNG_OK) {
4362 goto error;
4363 }
4364 }
4365
4366 snapshot_success = 1;
4367 } else {
4368 struct snapshot_output *sout;
4369 struct lttng_ht_iter iter;
4370
4371 rcu_read_lock();
4372 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
4373 &iter.iter, sout, node.node) {
4374 int64_t nb_packets_per_stream;
4375
4376 /*
4377 * Make a local copy of the output and assign the possible
4378 * temporary value given by the caller.
4379 */
4380 memset(&tmp_output, 0, sizeof(tmp_output));
4381 memcpy(&tmp_output, sout, sizeof(tmp_output));
4382
4383 if (output->max_size != (uint64_t) -1ULL) {
4384 tmp_output.max_size = output->max_size;
4385 }
4386
4387 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
4388 tmp_output.max_size);
4389 if (nb_packets_per_stream < 0) {
4390 ret = LTTNG_ERR_MAX_SIZE_INVALID;
4391 rcu_read_unlock();
4392 goto error;
4393 }
4394
4395 /* Use temporary name. */
4396 if (*output->name != '\0') {
4397 if (lttng_strncpy(tmp_output.name, output->name,
4398 sizeof(tmp_output.name))) {
4399 ret = LTTNG_ERR_INVALID;
4400 rcu_read_unlock();
4401 goto error;
4402 }
4403 }
4404
4405 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
4406 memcpy(tmp_output.datetime, datetime, sizeof(datetime));
4407
4408 if (session->kernel_session) {
4409 ret = record_kernel_snapshot(session->kernel_session,
4410 &tmp_output, session,
4411 wait, nb_packets_per_stream);
4412 if (ret != LTTNG_OK) {
4413 rcu_read_unlock();
4414 goto error;
4415 }
4416 }
4417
4418 if (session->ust_session) {
4419 ret = record_ust_snapshot(session->ust_session,
4420 &tmp_output, session,
4421 wait, nb_packets_per_stream);
4422 if (ret != LTTNG_OK) {
4423 rcu_read_unlock();
4424 goto error;
4425 }
4426 }
4427 snapshot_success = 1;
4428 }
4429 rcu_read_unlock();
4430 }
4431
4432 if (snapshot_success) {
4433 session->snapshot.nb_snapshot++;
4434 } else {
4435 ret = LTTNG_ERR_SNAPSHOT_FAIL;
4436 }
4437
4438 error:
4439 return ret;
4440 }
4441
4442 /*
4443 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
4444 */
4445 int cmd_set_session_shm_path(struct ltt_session *session,
4446 const char *shm_path)
4447 {
4448 /* Safety net */
4449 assert(session);
4450
4451 /*
4452 * Can only set shm path before session is started.
4453 */
4454 if (session->has_been_started) {
4455 return LTTNG_ERR_SESSION_STARTED;
4456 }
4457
4458 strncpy(session->shm_path, shm_path,
4459 sizeof(session->shm_path));
4460 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
4461
4462 return 0;
4463 }
4464
4465 /*
4466 * Command LTTNG_ROTATE_SESSION from the lttng-ctl library.
4467 *
4468 * Ask the consumer to rotate the session output directory.
4469 * The session lock must be held.
4470 *
4471 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4472 */
4473 int cmd_rotate_session(struct ltt_session *session,
4474 struct lttng_rotate_session_return *rotate_return)
4475 {
4476 int ret;
4477 size_t strf_ret;
4478 struct tm *timeinfo;
4479 char datetime[21];
4480 time_t now;
4481 bool ust_active = false;
4482
4483 assert(session);
4484
4485 if (!session->has_been_started) {
4486 ret = -LTTNG_ERR_START_SESSION_ONCE;
4487 goto end;
4488 }
4489
4490 if (session->live_timer || session->snapshot_mode ||
4491 !session->output_traces) {
4492 ret = -LTTNG_ERR_ROTATION_NOT_AVAILABLE;
4493 goto end;
4494 }
4495
4496 /*
4497 * Unsupported feature in lttng-relayd before 2.11.
4498 */
4499 if (session->consumer->type == CONSUMER_DST_NET &&
4500 (session->consumer->relay_major_version == 2 &&
4501 session->consumer->relay_minor_version < 11)) {
4502 ret = -LTTNG_ERR_ROTATION_NOT_AVAILABLE_RELAY;
4503 goto end;
4504 }
4505
4506 if (session->rotate_pending || session->rotate_pending_relay) {
4507 ret = -LTTNG_ERR_ROTATION_PENDING;
4508 DBG("Rotate already in progress");
4509 goto end;
4510 }
4511
4512 /*
4513 * After a stop, we only allow one rotation to occur, the other ones are
4514 * useless until a new start.
4515 */
4516 if (session->rotated_after_last_stop) {
4517 DBG("Session \"%s\" was already rotated after stop, refusing rotation",
4518 session->name);
4519 ret = -LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP;
4520 goto end;
4521 }
4522
4523 /* Special case for the first rotation. */
4524 if (session->current_archive_id == 0) {
4525 const char *base_path = NULL;
4526
4527 /* Either one of the two sessions is enough to get the root path. */
4528 if (session->kernel_session) {
4529 base_path = session_get_base_path(session);
4530 } else if (session->ust_session) {
4531 base_path = session_get_base_path(session);
4532 } else {
4533 assert(0);
4534 }
4535 assert(base_path);
4536 ret = lttng_strncpy(session->rotation_chunk.current_rotate_path,
4537 base_path,
4538 sizeof(session->rotation_chunk.current_rotate_path));
4539 if (ret) {
4540 ERR("Failed to copy session base path to current rotation chunk path");
4541 ret = -LTTNG_ERR_UNK;
4542 goto end;
4543 }
4544 } else {
4545 /*
4546 * The currently active tracing path is now the folder we
4547 * want to rotate.
4548 */
4549 ret = lttng_strncpy(session->rotation_chunk.current_rotate_path,
4550 session->rotation_chunk.active_tracing_path,
4551 sizeof(session->rotation_chunk.current_rotate_path));
4552 if (ret) {
4553 ERR("Failed to copy the active tracing path to the current rotate path");
4554 ret = -LTTNG_ERR_UNK;
4555 goto end;
4556 }
4557 }
4558 DBG("Current rotate path %s", session->rotation_chunk.current_rotate_path);
4559
4560 session->current_archive_id++;
4561 session->rotate_pending = true;
4562 session->rotation_state = LTTNG_ROTATION_STATE_ONGOING;
4563
4564 /*
4565 * Create the path name for the next chunk.
4566 */
4567 now = time(NULL);
4568 if (now == (time_t) -1) {
4569 ret = -LTTNG_ERR_ROTATION_NOT_AVAILABLE;
4570 goto end;
4571 }
4572 session->last_chunk_start_ts = session->current_chunk_start_ts;
4573 session->current_chunk_start_ts = now;
4574
4575 timeinfo = localtime(&now);
4576 if (!timeinfo) {
4577 PERROR("Failed to sample local time in rotate session command");
4578 ret = -LTTNG_ERR_UNK;
4579 goto end;
4580 }
4581 strf_ret = strftime(datetime, sizeof(datetime), "%Y%m%dT%H%M%S%z",
4582 timeinfo);
4583 if (!strf_ret) {
4584 ERR("Failed to format local time timestamp in rotate session command");
4585 ret = -LTTNG_ERR_UNK;
4586 goto end;
4587 }
4588 if (session->kernel_session) {
4589 /*
4590 * The active path for the next rotation/destroy.
4591 * Ex: ~/lttng-traces/auto-20170922-111748/20170922-111754-42
4592 */
4593 ret = snprintf(session->rotation_chunk.active_tracing_path,
4594 sizeof(session->rotation_chunk.active_tracing_path),
4595 "%s/%s-%" PRIu64,
4596 session_get_base_path(session),
4597 datetime, session->current_archive_id + 1);
4598 if (ret < 0 || ret == sizeof(session->rotation_chunk.active_tracing_path)) {
4599 ERR("Failed to format active kernel tracing path in rotate session command");
4600 ret = -LTTNG_ERR_UNK;
4601 goto end;
4602 }
4603 /*
4604 * The sub-directory for the consumer
4605 * Ex: /20170922-111754-42/kernel
4606 */
4607 ret = snprintf(session->kernel_session->consumer->chunk_path,
4608 sizeof(session->kernel_session->consumer->chunk_path),
4609 "/%s-%" PRIu64, datetime,
4610 session->current_archive_id + 1);
4611 if (ret < 0 || ret == sizeof(session->kernel_session->consumer->chunk_path)) {
4612 ERR("Failed to format the kernel consumer's sub-directory in rotate session command");
4613 ret = -LTTNG_ERR_UNK;
4614 goto end;
4615 }
4616 /*
4617 * Create the new chunk folder, before the rotation begins so we don't
4618 * race with the consumer/tracer activity.
4619 */
4620 ret = domain_mkdir(session->kernel_session->consumer, session,
4621 session->kernel_session->uid,
4622 session->kernel_session->gid);
4623 if (ret) {
4624 ERR("Failed to create kernel session tracing path at %s",
4625 session->kernel_session->consumer->chunk_path);
4626 ret = -LTTNG_ERR_CREATE_DIR_FAIL;
4627 goto end;
4628 }
4629 ret = kernel_rotate_session(session);
4630 if (ret != LTTNG_OK) {
4631 ret = -ret;
4632 goto end;
4633 }
4634 }
4635 if (session->ust_session) {
4636 ret = snprintf(session->rotation_chunk.active_tracing_path,
4637 PATH_MAX, "%s/%s-%" PRIu64,
4638 session_get_base_path(session),
4639 datetime, session->current_archive_id + 1);
4640 if (ret < 0) {
4641 ERR("Failed to format active UST tracing path in rotate session command");
4642 ret = -LTTNG_ERR_UNK;
4643 goto end;
4644 }
4645 ret = snprintf(session->ust_session->consumer->chunk_path,
4646 PATH_MAX, "/%s-%" PRIu64, datetime,
4647 session->current_archive_id + 1);
4648 if (ret < 0) {
4649 ERR("Failed to format the UST consumer's sub-directory in rotate session command");
4650 ret = -LTTNG_ERR_UNK;
4651 goto end;
4652 }
4653 /*
4654 * Create the new chunk folder, before the rotation begins so we don't
4655 * race with the consumer/tracer activity.
4656 */
4657 ret = domain_mkdir(session->ust_session->consumer, session,
4658 session->ust_session->uid,
4659 session->ust_session->gid);
4660 if (ret) {
4661 ret = -LTTNG_ERR_CREATE_DIR_FAIL;
4662 goto end;
4663 }
4664 ret = ust_app_rotate_session(session, &ust_active);
4665 if (ret != LTTNG_OK) {
4666 goto end;
4667 }
4668 /*
4669 * Handle the case where we did not start a rotation on any channel.
4670 * The consumer will never wake up the rotation thread to perform the
4671 * rename, so we have to do it here while we hold the session and
4672 * session_list locks.
4673 */
4674 if (!session->kernel_session && !ust_active) {
4675 ret = rename_complete_chunk(session, now);
4676 if (ret < 0) {
4677 ERR("Failed to rename completed rotation chunk");
4678 goto end;
4679 }
4680 session->rotate_pending = false;
4681 session->rotation_state = LTTNG_ROTATION_STATE_COMPLETED;
4682 }
4683 }
4684
4685 if (!session->active) {
4686 session->rotated_after_last_stop = true;
4687 }
4688
4689 if (rotate_return) {
4690 rotate_return->rotation_id = session->current_archive_id;
4691 }
4692
4693 DBG("Cmd rotate session %s, current_archive_id %" PRIu64 " sent",
4694 session->name, session->current_archive_id);
4695 ret = LTTNG_OK;
4696
4697 end:
4698 return ret;
4699 }
4700
4701 /*
4702 * Command LTTNG_ROTATION_GET_INFO from the lttng-ctl library.
4703 *
4704 * Check if the session has finished its rotation.
4705 *
4706 * Return 0 on success or else a LTTNG_ERR code.
4707 */
4708 int cmd_rotate_get_info(struct ltt_session *session,
4709 struct lttng_rotation_get_info_return *info_return,
4710 uint64_t rotation_id)
4711 {
4712 int ret;
4713
4714 assert(session);
4715
4716 DBG("Cmd rotate_get_info session %s, rotation id %" PRIu64, session->name,
4717 session->current_archive_id);
4718
4719 if (session->current_archive_id != rotation_id) {
4720 info_return->status = (int32_t) LTTNG_ROTATION_STATE_EXPIRED;
4721 ret = LTTNG_OK;
4722 goto end;
4723 }
4724
4725 switch (session->rotation_state) {
4726 case LTTNG_ROTATION_STATE_ONGOING:
4727 DBG("Reporting that rotation id %" PRIu64 " of session %s is still pending",
4728 rotation_id, session->name);
4729 break;
4730 case LTTNG_ROTATION_STATE_COMPLETED:
4731 {
4732 char *current_tracing_path_reply;
4733 size_t current_tracing_path_reply_len;
4734
4735 switch (session_get_consumer_destination_type(session)) {
4736 case CONSUMER_DST_LOCAL:
4737 current_tracing_path_reply =
4738 info_return->location.local.absolute_path;
4739 current_tracing_path_reply_len =
4740 sizeof(info_return->location.local.absolute_path);
4741 info_return->location_type =
4742 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_LOCAL;
4743 break;
4744 case CONSUMER_DST_NET:
4745 current_tracing_path_reply =
4746 info_return->location.relay.relative_path;
4747 current_tracing_path_reply_len =
4748 sizeof(info_return->location.relay.relative_path);
4749 /* Currently the only supported relay protocol. */
4750 info_return->location.relay.protocol =
4751 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP;
4752
4753 ret = lttng_strncpy(info_return->location.relay.host,
4754 session_get_net_consumer_hostname(session),
4755 sizeof(info_return->location.relay.host));
4756 if (ret) {
4757 ERR("Failed to host name to rotate_get_info reply");
4758 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
4759 ret = -LTTNG_ERR_UNK;
4760 goto end;
4761 }
4762
4763 session_get_net_consumer_ports(session,
4764 &info_return->location.relay.ports.control,
4765 &info_return->location.relay.ports.data);
4766 info_return->location_type =
4767 (int8_t) LTTNG_TRACE_ARCHIVE_LOCATION_TYPE_RELAY;
4768 break;
4769 default:
4770 abort();
4771 }
4772 ret = lttng_strncpy(current_tracing_path_reply,
4773 session->rotation_chunk.current_rotate_path,
4774 current_tracing_path_reply_len);
4775 if (ret) {
4776 ERR("Failed to copy current tracing path to rotate_get_info reply");
4777 info_return->status = LTTNG_ROTATION_STATUS_ERROR;
4778 ret = -LTTNG_ERR_UNK;
4779 goto end;
4780 }
4781
4782 break;
4783 }
4784 case LTTNG_ROTATION_STATE_ERROR:
4785 DBG("Reporting that an error occurred during rotation %" PRIu64 " of session %s",
4786 rotation_id, session->name);
4787 break;
4788 default:
4789 abort();
4790 }
4791
4792 info_return->status = (int32_t) session->rotation_state;
4793 ret = LTTNG_OK;
4794 end:
4795 return ret;
4796 }
4797
4798 /*
4799 * Command LTTNG_ROTATION_SET_SCHEDULE from the lttng-ctl library.
4800 *
4801 * Configure the automatic rotation parameters.
4802 * 'activate' to true means activate the rotation schedule type with 'new_value'.
4803 * 'activate' to false means deactivate the rotation schedule and validate that
4804 * 'new_value' has the same value as the currently active value.
4805 *
4806 * Return 0 on success or else a positive LTTNG_ERR code.
4807 */
4808 int cmd_rotation_set_schedule(struct ltt_session *session,
4809 bool activate, enum lttng_rotation_schedule_type schedule_type,
4810 uint64_t new_value,
4811 struct notification_thread_handle *notification_thread_handle)
4812 {
4813 int ret;
4814 uint64_t *parameter_value;
4815
4816 assert(session);
4817
4818 DBG("Cmd rotate set schedule session %s", session->name);
4819
4820 if (session->live_timer || session->snapshot_mode ||
4821 !session->output_traces) {
4822 DBG("Failing ROTATION_SET_SCHEDULE command as the rotation feature is not available for this session");
4823 ret = LTTNG_ERR_ROTATION_NOT_AVAILABLE;
4824 goto end;
4825 }
4826
4827 switch (schedule_type) {
4828 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
4829 parameter_value = &session->rotate_size;
4830 break;
4831 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
4832 parameter_value = &session->rotate_timer_period;
4833 if (new_value >= UINT_MAX) {
4834 DBG("Failing ROTATION_SET_SCHEDULE command as the value requested for a periodic rotation schedule is invalid: %" PRIu64 " > %u (UINT_MAX)",
4835 new_value, UINT_MAX);
4836 ret = LTTNG_ERR_INVALID;
4837 goto end;
4838 }
4839 break;
4840 default:
4841 WARN("Failing ROTATION_SET_SCHEDULE command on unknown schedule type");
4842 ret = LTTNG_ERR_INVALID;
4843 goto end;
4844 }
4845
4846 /* Improper use of the API. */
4847 if (new_value == -1ULL) {
4848 WARN("Failing ROTATION_SET_SCHEDULE command as the value requested is -1");
4849 ret = LTTNG_ERR_INVALID;
4850 goto end;
4851 }
4852
4853 /*
4854 * As indicated in struct ltt_session's comments, a value of == 0 means
4855 * this schedule rotation type is not in use.
4856 *
4857 * Reject the command if we were asked to activate a schedule that was
4858 * already active.
4859 */
4860 if (activate && *parameter_value != 0) {
4861 DBG("Failing ROTATION_SET_SCHEDULE (activate) command as the schedule is already active");
4862 ret = LTTNG_ERR_ROTATION_SCHEDULE_SET;
4863 goto end;
4864 }
4865
4866 /*
4867 * Reject the command if we were asked to deactivate a schedule that was
4868 * not active.
4869 */
4870 if (!activate && *parameter_value == 0) {
4871 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as the schedule is already inactive");
4872 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
4873 goto end;
4874 }
4875
4876 /*
4877 * Reject the command if we were asked to deactivate a schedule that
4878 * doesn't exist.
4879 */
4880 if (!activate && *parameter_value != new_value) {
4881 DBG("Failing ROTATION_SET_SCHEDULE (deactivate) command as an inexistant schedule was provided");
4882 ret = LTTNG_ERR_ROTATION_SCHEDULE_NOT_SET;
4883 goto end;
4884 }
4885
4886 *parameter_value = activate ? new_value : 0;
4887
4888 switch (schedule_type) {
4889 case LTTNG_ROTATION_SCHEDULE_TYPE_PERIODIC:
4890 if (activate && session->active) {
4891 /*
4892 * Only start the timer if the session is active,
4893 * otherwise it will be started when the session starts.
4894 */
4895 ret = sessiond_rotate_timer_start(session, new_value);
4896 if (ret) {
4897 ERR("Failed to enable session rotation timer in ROTATION_SET_SCHEDULE command");
4898 ret = LTTNG_ERR_UNK;
4899 goto end;
4900 }
4901 } else {
4902 ret = sessiond_rotate_timer_stop(session);
4903 if (ret) {
4904 ERR("Failed to disable session rotation timer in ROTATION_SET_SCHEDULE command");
4905 ret = LTTNG_ERR_UNK;
4906 goto end;
4907 }
4908 }
4909 break;
4910 case LTTNG_ROTATION_SCHEDULE_TYPE_SIZE_THRESHOLD:
4911 if (activate) {
4912 ret = subscribe_session_consumed_size_rotation(session,
4913 new_value, notification_thread_handle);
4914 if (ret) {
4915 ERR("Failed to enable consumed-size notification in ROTATION_SET_SCHEDULE command");
4916 ret = LTTNG_ERR_UNK;
4917 goto end;
4918 }
4919 } else {
4920 ret = unsubscribe_session_consumed_size_rotation(session,
4921 notification_thread_handle);
4922 if (ret) {
4923 ERR("Failed to disable consumed-size notification in ROTATION_SET_SCHEDULE command");
4924 ret = LTTNG_ERR_UNK;
4925 goto end;
4926 }
4927
4928 }
4929 break;
4930 default:
4931 /* Would have been caught before. */
4932 abort();
4933 }
4934
4935 ret = LTTNG_OK;
4936
4937 goto end;
4938
4939 end:
4940 return ret;
4941 }
4942
4943 /*
4944 * Command ROTATE_GET_CURRENT_PATH from the lttng-ctl library.
4945 *
4946 * Configure the automatic rotation parameters.
4947 * Set to -1ULL to disable them.
4948 *
4949 * Return LTTNG_OK on success or else a LTTNG_ERR code.
4950 */
4951 int cmd_session_get_current_output(struct ltt_session *session,
4952 struct lttng_session_get_current_output_return *output_return)
4953 {
4954 int ret;
4955 const char *path;
4956
4957 if (!session->snapshot_mode) {
4958 if (session->current_archive_id == 0) {
4959 if (session->kernel_session) {
4960 path = session_get_base_path(session);
4961 } else if (session->ust_session) {
4962 path = session_get_base_path(session);
4963 } else {
4964 abort();
4965 }
4966 assert(path);
4967 } else {
4968 path = session->rotation_chunk.active_tracing_path;
4969 }
4970 } else {
4971 /*
4972 * A snapshot session does not have a "current" trace archive
4973 * location.
4974 */
4975 path = "";
4976 }
4977
4978 DBG("Cmd get current output for session %s, returning %s",
4979 session->name, path);
4980
4981 ret = lttng_strncpy(output_return->path,
4982 path,
4983 sizeof(output_return->path));
4984 if (ret) {
4985 ERR("Failed to copy trace output path to session get current output command reply");
4986 ret = -LTTNG_ERR_UNK;
4987 goto end;
4988 }
4989
4990 ret = LTTNG_OK;
4991 end:
4992 return ret;
4993 }
4994
4995 /* Wait for a given path to be removed before continuing. */
4996 static enum lttng_error_code wait_on_path(void *path_data)
4997 {
4998 const char *shm_path = path_data;
4999
5000 DBG("Waiting for the shm path at %s to be removed before completing session destruction",
5001 shm_path);
5002 while (true) {
5003 int ret;
5004 struct stat st;
5005
5006 ret = stat(shm_path, &st);
5007 if (ret) {
5008 if (errno != ENOENT) {
5009 PERROR("stat() returned an error while checking for the existence of the shm path");
5010 } else {
5011 DBG("shm path no longer exists, completing the destruction of session");
5012 }
5013 break;
5014 } else {
5015 if (!S_ISDIR(st.st_mode)) {
5016 ERR("The type of shm path %s returned by stat() is not a directory; aborting the wait for shm path removal",
5017 shm_path);
5018 break;
5019 }
5020 }
5021 usleep(SESSION_DESTROY_SHM_PATH_CHECK_DELAY_US);
5022 }
5023 return LTTNG_OK;
5024 }
5025
5026 /*
5027 * Returns a pointer to a handler to run on completion of a command.
5028 * Returns NULL if no handler has to be run for the last command executed.
5029 */
5030 const struct cmd_completion_handler *cmd_pop_completion_handler(void)
5031 {
5032 struct cmd_completion_handler *handler = current_completion_handler;
5033
5034 current_completion_handler = NULL;
5035 return handler;
5036 }
5037
5038 /*
5039 * Init command subsystem.
5040 */
5041 void cmd_init(void)
5042 {
5043 /*
5044 * Set network sequence index to 1 for streams to match a relayd
5045 * socket on the consumer side.
5046 */
5047 pthread_mutex_lock(&relayd_net_seq_idx_lock);
5048 relayd_net_seq_idx = 1;
5049 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
5050
5051 DBG("Command subsystem initialized");
5052 }
LTTng 2.0 tools and control repository
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