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Document the locking assumptions of consumerd-relayd socket passing
[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
25 #include <common/defaults.h>
26 #include <common/common.h>
27 #include <common/sessiond-comm/sessiond-comm.h>
28 #include <common/relayd/relayd.h>
29 #include <common/utils.h>
30 #include <common/compat/string.h>
31 #include <common/kernel-ctl/kernel-ctl.h>
32
33 #include "channel.h"
34 #include "consumer.h"
35 #include "event.h"
36 #include "health-sessiond.h"
37 #include "kernel.h"
38 #include "kernel-consumer.h"
39 #include "lttng-sessiond.h"
40 #include "utils.h"
41 #include "syscall.h"
42 #include "agent.h"
43 #include "buffer-registry.h"
44
45 #include "cmd.h"
46
47 /*
48 * Used to keep a unique index for each relayd socket created where this value
49 * is associated with streams on the consumer so it can match the right relayd
50 * to send to. It must be accessed with the relayd_net_seq_idx_lock
51 * held.
52 */
53 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
54 static uint64_t relayd_net_seq_idx;
55
56 static int validate_event_name(const char *);
57 static int validate_ust_event_name(const char *);
58 static int cmd_enable_event_internal(struct ltt_session *session,
59 struct lttng_domain *domain,
60 char *channel_name, struct lttng_event *event,
61 char *filter_expression,
62 struct lttng_filter_bytecode *filter,
63 struct lttng_event_exclusion *exclusion,
64 int wpipe);
65
66 /*
67 * Create a session path used by list_lttng_sessions for the case that the
68 * session consumer is on the network.
69 */
70 static int build_network_session_path(char *dst, size_t size,
71 struct ltt_session *session)
72 {
73 int ret, kdata_port, udata_port;
74 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
75 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
76
77 assert(session);
78 assert(dst);
79
80 memset(tmp_urls, 0, sizeof(tmp_urls));
81 memset(tmp_uurl, 0, sizeof(tmp_uurl));
82
83 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
84
85 if (session->kernel_session && session->kernel_session->consumer) {
86 kuri = &session->kernel_session->consumer->dst.net.control;
87 kdata_port = session->kernel_session->consumer->dst.net.data.port;
88 }
89
90 if (session->ust_session && session->ust_session->consumer) {
91 uuri = &session->ust_session->consumer->dst.net.control;
92 udata_port = session->ust_session->consumer->dst.net.data.port;
93 }
94
95 if (uuri == NULL && kuri == NULL) {
96 uri = &session->consumer->dst.net.control;
97 kdata_port = session->consumer->dst.net.data.port;
98 } else if (kuri && uuri) {
99 ret = uri_compare(kuri, uuri);
100 if (ret) {
101 /* Not Equal */
102 uri = kuri;
103 /* Build uuri URL string */
104 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
105 if (ret < 0) {
106 goto error;
107 }
108 } else {
109 uri = kuri;
110 }
111 } else if (kuri && uuri == NULL) {
112 uri = kuri;
113 } else if (uuri && kuri == NULL) {
114 uri = uuri;
115 }
116
117 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
118 if (ret < 0) {
119 goto error;
120 }
121
122 /*
123 * Do we have a UST url set. If yes, this means we have both kernel and UST
124 * to print.
125 */
126 if (*tmp_uurl != '\0') {
127 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
128 tmp_urls, kdata_port, tmp_uurl, udata_port);
129 } else {
130 int dport;
131 if (kuri || (!kuri && !uuri)) {
132 dport = kdata_port;
133 } else {
134 /* No kernel URI, use the UST port. */
135 dport = udata_port;
136 }
137 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
138 }
139
140 error:
141 return ret;
142 }
143
144 /*
145 * Get run-time attributes if the session has been started (discarded events,
146 * lost packets).
147 */
148 static int get_kernel_runtime_stats(struct ltt_session *session,
149 struct ltt_kernel_channel *kchan, uint64_t *discarded_events,
150 uint64_t *lost_packets)
151 {
152 int ret;
153
154 if (!session->has_been_started) {
155 ret = 0;
156 *discarded_events = 0;
157 *lost_packets = 0;
158 goto end;
159 }
160
161 ret = consumer_get_discarded_events(session->id, kchan->fd,
162 session->kernel_session->consumer,
163 discarded_events);
164 if (ret < 0) {
165 goto end;
166 }
167
168 ret = consumer_get_lost_packets(session->id, kchan->fd,
169 session->kernel_session->consumer,
170 lost_packets);
171 if (ret < 0) {
172 goto end;
173 }
174
175 end:
176 return ret;
177 }
178
179 /*
180 * Get run-time attributes if the session has been started (discarded events,
181 * lost packets).
182 */
183 static int get_ust_runtime_stats(struct ltt_session *session,
184 struct ltt_ust_channel *uchan, uint64_t *discarded_events,
185 uint64_t *lost_packets)
186 {
187 int ret;
188 struct ltt_ust_session *usess;
189
190 if (!discarded_events || !lost_packets) {
191 ret = -1;
192 goto end;
193 }
194
195 usess = session->ust_session;
196 assert(discarded_events);
197 assert(lost_packets);
198
199 if (!usess || !session->has_been_started) {
200 *discarded_events = 0;
201 *lost_packets = 0;
202 ret = 0;
203 goto end;
204 }
205
206 if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
207 ret = ust_app_uid_get_channel_runtime_stats(usess->id,
208 &usess->buffer_reg_uid_list,
209 usess->consumer, uchan->id,
210 uchan->attr.overwrite,
211 discarded_events,
212 lost_packets);
213 } else if (usess->buffer_type == LTTNG_BUFFER_PER_PID) {
214 ret = ust_app_pid_get_channel_runtime_stats(usess,
215 uchan, usess->consumer,
216 uchan->attr.overwrite,
217 discarded_events,
218 lost_packets);
219 if (ret < 0) {
220 goto end;
221 }
222 *discarded_events += uchan->per_pid_closed_app_discarded;
223 *lost_packets += uchan->per_pid_closed_app_lost;
224 } else {
225 ERR("Unsupported buffer type");
226 assert(0);
227 ret = -1;
228 goto end;
229 }
230
231 end:
232 return ret;
233 }
234
235 /*
236 * Fill lttng_channel array of all channels.
237 */
238 static ssize_t list_lttng_channels(enum lttng_domain_type domain,
239 struct ltt_session *session, struct lttng_channel *channels,
240 struct lttcomm_channel_extended *chan_exts)
241 {
242 int i = 0, ret = 0;
243 struct ltt_kernel_channel *kchan;
244
245 DBG("Listing channels for session %s", session->name);
246
247 switch (domain) {
248 case LTTNG_DOMAIN_KERNEL:
249 /* Kernel channels */
250 if (session->kernel_session != NULL) {
251 cds_list_for_each_entry(kchan,
252 &session->kernel_session->channel_list.head, list) {
253 uint64_t discarded_events, lost_packets;
254
255 ret = get_kernel_runtime_stats(session, kchan,
256 &discarded_events, &lost_packets);
257 if (ret < 0) {
258 goto end;
259 }
260 /* Copy lttng_channel struct to array */
261 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
262 channels[i].enabled = kchan->enabled;
263 chan_exts[i].discarded_events =
264 discarded_events;
265 chan_exts[i].lost_packets = lost_packets;
266 i++;
267 }
268 }
269 break;
270 case LTTNG_DOMAIN_UST:
271 {
272 struct lttng_ht_iter iter;
273 struct ltt_ust_channel *uchan;
274
275 rcu_read_lock();
276 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
277 &iter.iter, uchan, node.node) {
278 uint64_t discarded_events = 0, lost_packets = 0;
279
280 if (lttng_strncpy(channels[i].name, uchan->name,
281 LTTNG_SYMBOL_NAME_LEN)) {
282 break;
283 }
284 channels[i].attr.overwrite = uchan->attr.overwrite;
285 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
286 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
287 channels[i].attr.switch_timer_interval =
288 uchan->attr.switch_timer_interval;
289 channels[i].attr.read_timer_interval =
290 uchan->attr.read_timer_interval;
291 channels[i].enabled = uchan->enabled;
292 channels[i].attr.tracefile_size = uchan->tracefile_size;
293 channels[i].attr.tracefile_count = uchan->tracefile_count;
294
295 /*
296 * Map enum lttng_ust_output to enum lttng_event_output.
297 */
298 switch (uchan->attr.output) {
299 case LTTNG_UST_MMAP:
300 channels[i].attr.output = LTTNG_EVENT_MMAP;
301 break;
302 default:
303 /*
304 * LTTNG_UST_MMAP is the only supported UST
305 * output mode.
306 */
307 assert(0);
308 break;
309 }
310
311 ret = get_ust_runtime_stats(session, uchan,
312 &discarded_events, &lost_packets);
313 if (ret < 0) {
314 break;
315 }
316 chan_exts[i].discarded_events = discarded_events;
317 chan_exts[i].lost_packets = lost_packets;
318 i++;
319 }
320 rcu_read_unlock();
321 break;
322 }
323 default:
324 break;
325 }
326
327 end:
328 if (ret < 0) {
329 return -LTTNG_ERR_FATAL;
330 } else {
331 return LTTNG_OK;
332 }
333 }
334
335 static void increment_extended_len(const char *filter_expression,
336 struct lttng_event_exclusion *exclusion, size_t *extended_len)
337 {
338 *extended_len += sizeof(struct lttcomm_event_extended_header);
339
340 if (filter_expression) {
341 *extended_len += strlen(filter_expression) + 1;
342 }
343
344 if (exclusion) {
345 *extended_len += exclusion->count * LTTNG_SYMBOL_NAME_LEN;
346 }
347 }
348
349 static void append_extended_info(const char *filter_expression,
350 struct lttng_event_exclusion *exclusion, void **extended_at)
351 {
352 struct lttcomm_event_extended_header extended_header;
353 size_t filter_len = 0;
354 size_t nb_exclusions = 0;
355
356 if (filter_expression) {
357 filter_len = strlen(filter_expression) + 1;
358 }
359
360 if (exclusion) {
361 nb_exclusions = exclusion->count;
362 }
363
364 /* Set header fields */
365 extended_header.filter_len = filter_len;
366 extended_header.nb_exclusions = nb_exclusions;
367
368 /* Copy header */
369 memcpy(*extended_at, &extended_header, sizeof(extended_header));
370 *extended_at += sizeof(extended_header);
371
372 /* Copy filter string */
373 if (filter_expression) {
374 memcpy(*extended_at, filter_expression, filter_len);
375 *extended_at += filter_len;
376 }
377
378 /* Copy exclusion names */
379 if (exclusion) {
380 size_t len = nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
381
382 memcpy(*extended_at, &exclusion->names, len);
383 *extended_at += len;
384 }
385 }
386
387 /*
388 * Create a list of agent domain events.
389 *
390 * Return number of events in list on success or else a negative value.
391 */
392 static int list_lttng_agent_events(struct agent *agt,
393 struct lttng_event **events, size_t *total_size)
394 {
395 int i = 0, ret = 0;
396 unsigned int nb_event = 0;
397 struct agent_event *event;
398 struct lttng_event *tmp_events;
399 struct lttng_ht_iter iter;
400 size_t extended_len = 0;
401 void *extended_at;
402
403 assert(agt);
404 assert(events);
405
406 DBG3("Listing agent events");
407
408 rcu_read_lock();
409 nb_event = lttng_ht_get_count(agt->events);
410 rcu_read_unlock();
411 if (nb_event == 0) {
412 ret = nb_event;
413 *total_size = 0;
414 goto error;
415 }
416
417 /* Compute required extended infos size */
418 extended_len = nb_event * sizeof(struct lttcomm_event_extended_header);
419
420 /*
421 * This is only valid because the commands which add events are
422 * processed in the same thread as the listing.
423 */
424 rcu_read_lock();
425 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
426 increment_extended_len(event->filter_expression, NULL,
427 &extended_len);
428 }
429 rcu_read_unlock();
430
431 *total_size = nb_event * sizeof(*tmp_events) + extended_len;
432 tmp_events = zmalloc(*total_size);
433 if (!tmp_events) {
434 PERROR("zmalloc agent events session");
435 ret = -LTTNG_ERR_FATAL;
436 goto error;
437 }
438
439 extended_at = ((uint8_t *) tmp_events) +
440 nb_event * sizeof(struct lttng_event);
441
442 rcu_read_lock();
443 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
444 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
445 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
446 tmp_events[i].enabled = event->enabled;
447 tmp_events[i].loglevel = event->loglevel_value;
448 tmp_events[i].loglevel_type = event->loglevel_type;
449 i++;
450
451 /* Append extended info */
452 append_extended_info(event->filter_expression, NULL,
453 &extended_at);
454 }
455 rcu_read_unlock();
456
457 *events = tmp_events;
458 ret = nb_event;
459
460 error:
461 assert(nb_event == i);
462 return ret;
463 }
464
465 /*
466 * Create a list of ust global domain events.
467 */
468 static int list_lttng_ust_global_events(char *channel_name,
469 struct ltt_ust_domain_global *ust_global,
470 struct lttng_event **events, size_t *total_size)
471 {
472 int i = 0, ret = 0;
473 unsigned int nb_event = 0;
474 struct lttng_ht_iter iter;
475 struct lttng_ht_node_str *node;
476 struct ltt_ust_channel *uchan;
477 struct ltt_ust_event *uevent;
478 struct lttng_event *tmp;
479 size_t extended_len = 0;
480 void *extended_at;
481
482 DBG("Listing UST global events for channel %s", channel_name);
483
484 rcu_read_lock();
485
486 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
487 node = lttng_ht_iter_get_node_str(&iter);
488 if (node == NULL) {
489 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
490 goto end;
491 }
492
493 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
494
495 nb_event = lttng_ht_get_count(uchan->events);
496 if (nb_event == 0) {
497 ret = nb_event;
498 *total_size = 0;
499 goto end;
500 }
501
502 DBG3("Listing UST global %d events", nb_event);
503
504 /* Compute required extended infos size */
505 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
506 if (uevent->internal) {
507 nb_event--;
508 continue;
509 }
510
511 increment_extended_len(uevent->filter_expression,
512 uevent->exclusion, &extended_len);
513 }
514 if (nb_event == 0) {
515 /* All events are internal, skip. */
516 ret = 0;
517 *total_size = 0;
518 goto end;
519 }
520
521 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
522 tmp = zmalloc(*total_size);
523 if (tmp == NULL) {
524 ret = -LTTNG_ERR_FATAL;
525 goto end;
526 }
527
528 extended_at = ((uint8_t *) tmp) + nb_event * sizeof(struct lttng_event);
529
530 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
531 if (uevent->internal) {
532 /* This event should remain hidden from clients */
533 continue;
534 }
535 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
536 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
537 tmp[i].enabled = uevent->enabled;
538
539 switch (uevent->attr.instrumentation) {
540 case LTTNG_UST_TRACEPOINT:
541 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
542 break;
543 case LTTNG_UST_PROBE:
544 tmp[i].type = LTTNG_EVENT_PROBE;
545 break;
546 case LTTNG_UST_FUNCTION:
547 tmp[i].type = LTTNG_EVENT_FUNCTION;
548 break;
549 }
550
551 tmp[i].loglevel = uevent->attr.loglevel;
552 switch (uevent->attr.loglevel_type) {
553 case LTTNG_UST_LOGLEVEL_ALL:
554 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
555 break;
556 case LTTNG_UST_LOGLEVEL_RANGE:
557 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
558 break;
559 case LTTNG_UST_LOGLEVEL_SINGLE:
560 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
561 break;
562 }
563 if (uevent->filter) {
564 tmp[i].filter = 1;
565 }
566 if (uevent->exclusion) {
567 tmp[i].exclusion = 1;
568 }
569 i++;
570
571 /* Append extended info */
572 append_extended_info(uevent->filter_expression,
573 uevent->exclusion, &extended_at);
574 }
575
576 ret = nb_event;
577 *events = tmp;
578 end:
579 rcu_read_unlock();
580 return ret;
581 }
582
583 /*
584 * Fill lttng_event array of all kernel events in the channel.
585 */
586 static int list_lttng_kernel_events(char *channel_name,
587 struct ltt_kernel_session *kernel_session,
588 struct lttng_event **events, size_t *total_size)
589 {
590 int i = 0, ret;
591 unsigned int nb_event;
592 struct ltt_kernel_event *event;
593 struct ltt_kernel_channel *kchan;
594 size_t extended_len = 0;
595 void *extended_at;
596
597 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
598 if (kchan == NULL) {
599 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
600 goto error;
601 }
602
603 nb_event = kchan->event_count;
604
605 DBG("Listing events for channel %s", kchan->channel->name);
606
607 if (nb_event == 0) {
608 *total_size = 0;
609 *events = NULL;
610 goto end;
611 }
612
613 /* Compute required extended infos size */
614 cds_list_for_each_entry(event, &kchan->events_list.head, list) {
615 increment_extended_len(event->filter_expression, NULL,
616 &extended_len);
617 }
618
619 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
620 *events = zmalloc(*total_size);
621 if (*events == NULL) {
622 ret = LTTNG_ERR_FATAL;
623 goto error;
624 }
625
626 extended_at = ((void *) *events) +
627 nb_event * sizeof(struct lttng_event);
628
629 /* Kernel channels */
630 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
631 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
632 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
633 (*events)[i].enabled = event->enabled;
634 (*events)[i].filter =
635 (unsigned char) !!event->filter_expression;
636
637 switch (event->event->instrumentation) {
638 case LTTNG_KERNEL_TRACEPOINT:
639 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
640 break;
641 case LTTNG_KERNEL_KRETPROBE:
642 (*events)[i].type = LTTNG_EVENT_FUNCTION;
643 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
644 sizeof(struct lttng_kernel_kprobe));
645 break;
646 case LTTNG_KERNEL_KPROBE:
647 (*events)[i].type = LTTNG_EVENT_PROBE;
648 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
649 sizeof(struct lttng_kernel_kprobe));
650 break;
651 case LTTNG_KERNEL_FUNCTION:
652 (*events)[i].type = LTTNG_EVENT_FUNCTION;
653 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
654 sizeof(struct lttng_kernel_function));
655 break;
656 case LTTNG_KERNEL_NOOP:
657 (*events)[i].type = LTTNG_EVENT_NOOP;
658 break;
659 case LTTNG_KERNEL_SYSCALL:
660 (*events)[i].type = LTTNG_EVENT_SYSCALL;
661 break;
662 case LTTNG_KERNEL_ALL:
663 assert(0);
664 break;
665 }
666 i++;
667
668 /* Append extended info */
669 append_extended_info(event->filter_expression, NULL,
670 &extended_at);
671 }
672
673 end:
674 return nb_event;
675
676 error:
677 /* Negate the error code to differentiate the size from an error */
678 return -ret;
679 }
680
681 /*
682 * Add URI so the consumer output object. Set the correct path depending on the
683 * domain adding the default trace directory.
684 */
685 static int add_uri_to_consumer(struct consumer_output *consumer,
686 struct lttng_uri *uri, enum lttng_domain_type domain,
687 const char *session_name)
688 {
689 int ret = LTTNG_OK;
690 const char *default_trace_dir;
691
692 assert(uri);
693
694 if (consumer == NULL) {
695 DBG("No consumer detected. Don't add URI. Stopping.");
696 ret = LTTNG_ERR_NO_CONSUMER;
697 goto error;
698 }
699
700 switch (domain) {
701 case LTTNG_DOMAIN_KERNEL:
702 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
703 break;
704 case LTTNG_DOMAIN_UST:
705 default_trace_dir = DEFAULT_UST_TRACE_DIR;
706 break;
707 default:
708 /*
709 * This case is possible is we try to add the URI to the global tracing
710 * session consumer object which in this case there is no subdir.
711 */
712 default_trace_dir = "";
713 }
714
715 switch (uri->dtype) {
716 case LTTNG_DST_IPV4:
717 case LTTNG_DST_IPV6:
718 DBG2("Setting network URI to consumer");
719
720 if (consumer->type == CONSUMER_DST_NET) {
721 if ((uri->stype == LTTNG_STREAM_CONTROL &&
722 consumer->dst.net.control_isset) ||
723 (uri->stype == LTTNG_STREAM_DATA &&
724 consumer->dst.net.data_isset)) {
725 ret = LTTNG_ERR_URL_EXIST;
726 goto error;
727 }
728 } else {
729 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
730 }
731
732 consumer->type = CONSUMER_DST_NET;
733
734 /* Set URI into consumer output object */
735 ret = consumer_set_network_uri(consumer, uri);
736 if (ret < 0) {
737 ret = -ret;
738 goto error;
739 } else if (ret == 1) {
740 /*
741 * URI was the same in the consumer so we do not append the subdir
742 * again so to not duplicate output dir.
743 */
744 ret = LTTNG_OK;
745 goto error;
746 }
747
748 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
749 ret = consumer_set_subdir(consumer, session_name);
750 if (ret < 0) {
751 ret = LTTNG_ERR_FATAL;
752 goto error;
753 }
754 }
755
756 if (uri->stype == LTTNG_STREAM_CONTROL) {
757 /* On a new subdir, reappend the default trace dir. */
758 strncat(consumer->subdir, default_trace_dir,
759 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
760 DBG3("Append domain trace name to subdir %s", consumer->subdir);
761 }
762
763 break;
764 case LTTNG_DST_PATH:
765 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
766 memset(consumer->dst.trace_path, 0,
767 sizeof(consumer->dst.trace_path));
768 /* Explicit length checks for strcpy and strcat. */
769 if (strlen(uri->dst.path) + strlen(default_trace_dir)
770 >= sizeof(consumer->dst.trace_path)) {
771 ret = LTTNG_ERR_FATAL;
772 goto error;
773 }
774 strcpy(consumer->dst.trace_path, uri->dst.path);
775 /* Append default trace dir */
776 strcat(consumer->dst.trace_path, default_trace_dir);
777 /* Flag consumer as local. */
778 consumer->type = CONSUMER_DST_LOCAL;
779 break;
780 }
781
782 ret = LTTNG_OK;
783
784 error:
785 return ret;
786 }
787
788 /*
789 * Init tracing by creating trace directory and sending fds kernel consumer.
790 */
791 static int init_kernel_tracing(struct ltt_kernel_session *session)
792 {
793 int ret = 0;
794 struct lttng_ht_iter iter;
795 struct consumer_socket *socket;
796
797 assert(session);
798
799 rcu_read_lock();
800
801 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
802 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
803 socket, node.node) {
804 pthread_mutex_lock(socket->lock);
805 ret = kernel_consumer_send_session(socket, session);
806 pthread_mutex_unlock(socket->lock);
807 if (ret < 0) {
808 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
809 goto error;
810 }
811 }
812 }
813
814 error:
815 rcu_read_unlock();
816 return ret;
817 }
818
819 /*
820 * Create a socket to the relayd using the URI.
821 *
822 * On success, the relayd_sock pointer is set to the created socket.
823 * Else, it's stays untouched and a lttcomm error code is returned.
824 */
825 static int create_connect_relayd(struct lttng_uri *uri,
826 struct lttcomm_relayd_sock **relayd_sock,
827 struct consumer_output *consumer)
828 {
829 int ret;
830 struct lttcomm_relayd_sock *rsock;
831
832 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
833 RELAYD_VERSION_COMM_MINOR);
834 if (!rsock) {
835 ret = LTTNG_ERR_FATAL;
836 goto error;
837 }
838
839 /*
840 * Connect to relayd so we can proceed with a session creation. This call
841 * can possibly block for an arbitrary amount of time to set the health
842 * state to be in poll execution.
843 */
844 health_poll_entry();
845 ret = relayd_connect(rsock);
846 health_poll_exit();
847 if (ret < 0) {
848 ERR("Unable to reach lttng-relayd");
849 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
850 goto free_sock;
851 }
852
853 /* Create socket for control stream. */
854 if (uri->stype == LTTNG_STREAM_CONTROL) {
855 DBG3("Creating relayd stream socket from URI");
856
857 /* Check relayd version */
858 ret = relayd_version_check(rsock);
859 if (ret < 0) {
860 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
861 goto close_sock;
862 }
863 consumer->relay_major_version = rsock->major;
864 consumer->relay_minor_version = rsock->minor;
865 } else if (uri->stype == LTTNG_STREAM_DATA) {
866 DBG3("Creating relayd data socket from URI");
867 } else {
868 /* Command is not valid */
869 ERR("Relayd invalid stream type: %d", uri->stype);
870 ret = LTTNG_ERR_INVALID;
871 goto close_sock;
872 }
873
874 *relayd_sock = rsock;
875
876 return LTTNG_OK;
877
878 close_sock:
879 /* The returned value is not useful since we are on an error path. */
880 (void) relayd_close(rsock);
881 free_sock:
882 free(rsock);
883 error:
884 return ret;
885 }
886
887 /*
888 * Connect to the relayd using URI and send the socket to the right consumer.
889 *
890 * The consumer socket lock must be held by the caller.
891 */
892 static int send_consumer_relayd_socket(enum lttng_domain_type domain,
893 unsigned int session_id, struct lttng_uri *relayd_uri,
894 struct consumer_output *consumer,
895 struct consumer_socket *consumer_sock,
896 char *session_name, char *hostname, int session_live_timer)
897 {
898 int ret;
899 struct lttcomm_relayd_sock *rsock = NULL;
900
901 /* Connect to relayd and make version check if uri is the control. */
902 ret = create_connect_relayd(relayd_uri, &rsock, consumer);
903 if (ret != LTTNG_OK) {
904 goto relayd_comm_error;
905 }
906 assert(rsock);
907
908 /* Set the network sequence index if not set. */
909 if (consumer->net_seq_index == (uint64_t) -1ULL) {
910 pthread_mutex_lock(&relayd_net_seq_idx_lock);
911 /*
912 * Increment net_seq_idx because we are about to transfer the
913 * new relayd socket to the consumer.
914 * Assign unique key so the consumer can match streams.
915 */
916 consumer->net_seq_index = ++relayd_net_seq_idx;
917 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
918 }
919
920 /* Send relayd socket to consumer. */
921 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
922 relayd_uri->stype, session_id,
923 session_name, hostname, session_live_timer);
924 if (ret < 0) {
925 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
926 goto close_sock;
927 }
928
929 /* Flag that the corresponding socket was sent. */
930 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
931 consumer_sock->control_sock_sent = 1;
932 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
933 consumer_sock->data_sock_sent = 1;
934 }
935
936 ret = LTTNG_OK;
937
938 /*
939 * Close socket which was dup on the consumer side. The session daemon does
940 * NOT keep track of the relayd socket(s) once transfer to the consumer.
941 */
942
943 close_sock:
944 if (ret != LTTNG_OK) {
945 /*
946 * The consumer output for this session should not be used anymore
947 * since the relayd connection failed thus making any tracing or/and
948 * streaming not usable.
949 */
950 consumer->enabled = 0;
951 }
952 (void) relayd_close(rsock);
953 free(rsock);
954
955 relayd_comm_error:
956 return ret;
957 }
958
959 /*
960 * Send both relayd sockets to a specific consumer and domain. This is a
961 * helper function to facilitate sending the information to the consumer for a
962 * session.
963 *
964 * The consumer socket lock must be held by the caller.
965 */
966 static int send_consumer_relayd_sockets(enum lttng_domain_type domain,
967 unsigned int session_id, struct consumer_output *consumer,
968 struct consumer_socket *sock, char *session_name,
969 char *hostname, int session_live_timer)
970 {
971 int ret = LTTNG_OK;
972
973 assert(consumer);
974 assert(sock);
975
976 /* Sending control relayd socket. */
977 if (!sock->control_sock_sent) {
978 ret = send_consumer_relayd_socket(domain, session_id,
979 &consumer->dst.net.control, consumer, sock,
980 session_name, hostname, session_live_timer);
981 if (ret != LTTNG_OK) {
982 goto error;
983 }
984 }
985
986 /* Sending data relayd socket. */
987 if (!sock->data_sock_sent) {
988 ret = send_consumer_relayd_socket(domain, session_id,
989 &consumer->dst.net.data, consumer, sock,
990 session_name, hostname, session_live_timer);
991 if (ret != LTTNG_OK) {
992 goto error;
993 }
994 }
995
996 error:
997 return ret;
998 }
999
1000 /*
1001 * Setup relayd connections for a tracing session. First creates the socket to
1002 * the relayd and send them to the right domain consumer. Consumer type MUST be
1003 * network.
1004 */
1005 int cmd_setup_relayd(struct ltt_session *session)
1006 {
1007 int ret = LTTNG_OK;
1008 struct ltt_ust_session *usess;
1009 struct ltt_kernel_session *ksess;
1010 struct consumer_socket *socket;
1011 struct lttng_ht_iter iter;
1012
1013 assert(session);
1014
1015 usess = session->ust_session;
1016 ksess = session->kernel_session;
1017
1018 DBG("Setting relayd for session %s", session->name);
1019
1020 rcu_read_lock();
1021
1022 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1023 && usess->consumer->enabled) {
1024 /* For each consumer socket, send relayd sockets */
1025 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1026 socket, node.node) {
1027 pthread_mutex_lock(socket->lock);
1028 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1029 usess->consumer, socket,
1030 session->name, session->hostname,
1031 session->live_timer);
1032 pthread_mutex_unlock(socket->lock);
1033 if (ret != LTTNG_OK) {
1034 goto error;
1035 }
1036 /* Session is now ready for network streaming. */
1037 session->net_handle = 1;
1038 }
1039 session->consumer->relay_major_version =
1040 usess->consumer->relay_major_version;
1041 session->consumer->relay_minor_version =
1042 usess->consumer->relay_minor_version;
1043 }
1044
1045 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1046 && ksess->consumer->enabled) {
1047 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1048 socket, node.node) {
1049 pthread_mutex_lock(socket->lock);
1050 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1051 ksess->consumer, socket,
1052 session->name, session->hostname,
1053 session->live_timer);
1054 pthread_mutex_unlock(socket->lock);
1055 if (ret != LTTNG_OK) {
1056 goto error;
1057 }
1058 /* Session is now ready for network streaming. */
1059 session->net_handle = 1;
1060 }
1061 session->consumer->relay_major_version =
1062 ksess->consumer->relay_major_version;
1063 session->consumer->relay_minor_version =
1064 ksess->consumer->relay_minor_version;
1065 }
1066
1067 error:
1068 rcu_read_unlock();
1069 return ret;
1070 }
1071
1072 /*
1073 * Start a kernel session by opening all necessary streams.
1074 */
1075 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
1076 {
1077 int ret;
1078 struct ltt_kernel_channel *kchan;
1079
1080 /* Open kernel metadata */
1081 if (ksess->metadata == NULL && ksess->output_traces) {
1082 ret = kernel_open_metadata(ksess);
1083 if (ret < 0) {
1084 ret = LTTNG_ERR_KERN_META_FAIL;
1085 goto error;
1086 }
1087 }
1088
1089 /* Open kernel metadata stream */
1090 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1091 ret = kernel_open_metadata_stream(ksess);
1092 if (ret < 0) {
1093 ERR("Kernel create metadata stream failed");
1094 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1095 goto error;
1096 }
1097 }
1098
1099 /* For each channel */
1100 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1101 if (kchan->stream_count == 0) {
1102 ret = kernel_open_channel_stream(kchan);
1103 if (ret < 0) {
1104 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1105 goto error;
1106 }
1107 /* Update the stream global counter */
1108 ksess->stream_count_global += ret;
1109 }
1110 }
1111
1112 /* Setup kernel consumer socket and send fds to it */
1113 ret = init_kernel_tracing(ksess);
1114 if (ret != 0) {
1115 ret = LTTNG_ERR_KERN_START_FAIL;
1116 goto error;
1117 }
1118
1119 /* This start the kernel tracing */
1120 ret = kernel_start_session(ksess);
1121 if (ret < 0) {
1122 ret = LTTNG_ERR_KERN_START_FAIL;
1123 goto error;
1124 }
1125
1126 /* Quiescent wait after starting trace */
1127 kernel_wait_quiescent(kernel_tracer_fd);
1128
1129 ksess->active = 1;
1130
1131 ret = LTTNG_OK;
1132
1133 error:
1134 return ret;
1135 }
1136
1137 /*
1138 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1139 */
1140 int cmd_disable_channel(struct ltt_session *session,
1141 enum lttng_domain_type domain, char *channel_name)
1142 {
1143 int ret;
1144 struct ltt_ust_session *usess;
1145
1146 usess = session->ust_session;
1147
1148 rcu_read_lock();
1149
1150 switch (domain) {
1151 case LTTNG_DOMAIN_KERNEL:
1152 {
1153 ret = channel_kernel_disable(session->kernel_session,
1154 channel_name);
1155 if (ret != LTTNG_OK) {
1156 goto error;
1157 }
1158
1159 kernel_wait_quiescent(kernel_tracer_fd);
1160 break;
1161 }
1162 case LTTNG_DOMAIN_UST:
1163 {
1164 struct ltt_ust_channel *uchan;
1165 struct lttng_ht *chan_ht;
1166
1167 chan_ht = usess->domain_global.channels;
1168
1169 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1170 if (uchan == NULL) {
1171 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1172 goto error;
1173 }
1174
1175 ret = channel_ust_disable(usess, uchan);
1176 if (ret != LTTNG_OK) {
1177 goto error;
1178 }
1179 break;
1180 }
1181 default:
1182 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1183 goto error;
1184 }
1185
1186 ret = LTTNG_OK;
1187
1188 error:
1189 rcu_read_unlock();
1190 return ret;
1191 }
1192
1193 /*
1194 * Command LTTNG_TRACK_PID processed by the client thread.
1195 *
1196 * Called with session lock held.
1197 */
1198 int cmd_track_pid(struct ltt_session *session, enum lttng_domain_type domain,
1199 int pid)
1200 {
1201 int ret;
1202
1203 rcu_read_lock();
1204
1205 switch (domain) {
1206 case LTTNG_DOMAIN_KERNEL:
1207 {
1208 struct ltt_kernel_session *ksess;
1209
1210 ksess = session->kernel_session;
1211
1212 ret = kernel_track_pid(ksess, pid);
1213 if (ret != LTTNG_OK) {
1214 goto error;
1215 }
1216
1217 kernel_wait_quiescent(kernel_tracer_fd);
1218 break;
1219 }
1220 case LTTNG_DOMAIN_UST:
1221 {
1222 struct ltt_ust_session *usess;
1223
1224 usess = session->ust_session;
1225
1226 ret = trace_ust_track_pid(usess, pid);
1227 if (ret != LTTNG_OK) {
1228 goto error;
1229 }
1230 break;
1231 }
1232 default:
1233 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1234 goto error;
1235 }
1236
1237 ret = LTTNG_OK;
1238
1239 error:
1240 rcu_read_unlock();
1241 return ret;
1242 }
1243
1244 /*
1245 * Command LTTNG_UNTRACK_PID processed by the client thread.
1246 *
1247 * Called with session lock held.
1248 */
1249 int cmd_untrack_pid(struct ltt_session *session, enum lttng_domain_type domain,
1250 int pid)
1251 {
1252 int ret;
1253
1254 rcu_read_lock();
1255
1256 switch (domain) {
1257 case LTTNG_DOMAIN_KERNEL:
1258 {
1259 struct ltt_kernel_session *ksess;
1260
1261 ksess = session->kernel_session;
1262
1263 ret = kernel_untrack_pid(ksess, pid);
1264 if (ret != LTTNG_OK) {
1265 goto error;
1266 }
1267
1268 kernel_wait_quiescent(kernel_tracer_fd);
1269 break;
1270 }
1271 case LTTNG_DOMAIN_UST:
1272 {
1273 struct ltt_ust_session *usess;
1274
1275 usess = session->ust_session;
1276
1277 ret = trace_ust_untrack_pid(usess, pid);
1278 if (ret != LTTNG_OK) {
1279 goto error;
1280 }
1281 break;
1282 }
1283 default:
1284 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1285 goto error;
1286 }
1287
1288 ret = LTTNG_OK;
1289
1290 error:
1291 rcu_read_unlock();
1292 return ret;
1293 }
1294
1295 /*
1296 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1297 *
1298 * The wpipe arguments is used as a notifier for the kernel thread.
1299 */
1300 int cmd_enable_channel(struct ltt_session *session,
1301 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1302 {
1303 int ret;
1304 struct ltt_ust_session *usess = session->ust_session;
1305 struct lttng_ht *chan_ht;
1306 size_t len;
1307
1308 assert(session);
1309 assert(attr);
1310 assert(domain);
1311
1312 len = lttng_strnlen(attr->name, sizeof(attr->name));
1313
1314 /* Validate channel name */
1315 if (attr->name[0] == '.' ||
1316 memchr(attr->name, '/', len) != NULL) {
1317 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1318 goto end;
1319 }
1320
1321 DBG("Enabling channel %s for session %s", attr->name, session->name);
1322
1323 rcu_read_lock();
1324
1325 /*
1326 * Don't try to enable a channel if the session has been started at
1327 * some point in time before. The tracer does not allow it.
1328 */
1329 if (session->has_been_started) {
1330 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1331 goto error;
1332 }
1333
1334 /*
1335 * If the session is a live session, remove the switch timer, the
1336 * live timer does the same thing but sends also synchronisation
1337 * beacons for inactive streams.
1338 */
1339 if (session->live_timer > 0) {
1340 attr->attr.live_timer_interval = session->live_timer;
1341 attr->attr.switch_timer_interval = 0;
1342 }
1343
1344 switch (domain->type) {
1345 case LTTNG_DOMAIN_KERNEL:
1346 {
1347 struct ltt_kernel_channel *kchan;
1348
1349 kchan = trace_kernel_get_channel_by_name(attr->name,
1350 session->kernel_session);
1351 if (kchan == NULL) {
1352 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1353 if (attr->name[0] != '\0') {
1354 session->kernel_session->has_non_default_channel = 1;
1355 }
1356 } else {
1357 ret = channel_kernel_enable(session->kernel_session, kchan);
1358 }
1359
1360 if (ret != LTTNG_OK) {
1361 goto error;
1362 }
1363
1364 kernel_wait_quiescent(kernel_tracer_fd);
1365 break;
1366 }
1367 case LTTNG_DOMAIN_UST:
1368 case LTTNG_DOMAIN_JUL:
1369 case LTTNG_DOMAIN_LOG4J:
1370 case LTTNG_DOMAIN_PYTHON:
1371 {
1372 struct ltt_ust_channel *uchan;
1373
1374 /*
1375 * FIXME
1376 *
1377 * Current agent implementation limitations force us to allow
1378 * only one channel at once in "agent" subdomains. Each
1379 * subdomain has a default channel name which must be strictly
1380 * adhered to.
1381 */
1382 if (domain->type == LTTNG_DOMAIN_JUL) {
1383 if (strncmp(attr->name, DEFAULT_JUL_CHANNEL_NAME,
1384 LTTNG_SYMBOL_NAME_LEN)) {
1385 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1386 goto error;
1387 }
1388 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1389 if (strncmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME,
1390 LTTNG_SYMBOL_NAME_LEN)) {
1391 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1392 goto error;
1393 }
1394 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1395 if (strncmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME,
1396 LTTNG_SYMBOL_NAME_LEN)) {
1397 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1398 goto error;
1399 }
1400 }
1401
1402 chan_ht = usess->domain_global.channels;
1403
1404 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1405 if (uchan == NULL) {
1406 ret = channel_ust_create(usess, attr, domain->buf_type);
1407 if (attr->name[0] != '\0') {
1408 usess->has_non_default_channel = 1;
1409 }
1410 } else {
1411 ret = channel_ust_enable(usess, uchan);
1412 }
1413 break;
1414 }
1415 default:
1416 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1417 goto error;
1418 }
1419
1420 error:
1421 rcu_read_unlock();
1422 end:
1423 return ret;
1424 }
1425
1426 /*
1427 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1428 */
1429 int cmd_disable_event(struct ltt_session *session,
1430 enum lttng_domain_type domain, char *channel_name,
1431 struct lttng_event *event)
1432 {
1433 int ret;
1434 char *event_name;
1435
1436 DBG("Disable event command for event \'%s\'", event->name);
1437
1438 event_name = event->name;
1439 if (validate_event_name(event_name)) {
1440 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1441 goto error;
1442 }
1443
1444 /* Error out on unhandled search criteria */
1445 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1446 || event->pid || event->filter || event->exclusion) {
1447 ret = LTTNG_ERR_UNK;
1448 goto error;
1449 }
1450
1451 rcu_read_lock();
1452
1453 switch (domain) {
1454 case LTTNG_DOMAIN_KERNEL:
1455 {
1456 struct ltt_kernel_channel *kchan;
1457 struct ltt_kernel_session *ksess;
1458
1459 ksess = session->kernel_session;
1460
1461 /*
1462 * If a non-default channel has been created in the
1463 * session, explicitely require that -c chan_name needs
1464 * to be provided.
1465 */
1466 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1467 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1468 goto error_unlock;
1469 }
1470
1471 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1472 if (kchan == NULL) {
1473 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1474 goto error_unlock;
1475 }
1476
1477 switch (event->type) {
1478 case LTTNG_EVENT_ALL:
1479 case LTTNG_EVENT_TRACEPOINT:
1480 case LTTNG_EVENT_SYSCALL:
1481 case LTTNG_EVENT_PROBE:
1482 case LTTNG_EVENT_FUNCTION:
1483 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1484 if (event_name[0] == '\0') {
1485 ret = event_kernel_disable_event(kchan,
1486 NULL, event->type);
1487 } else {
1488 ret = event_kernel_disable_event(kchan,
1489 event_name, event->type);
1490 }
1491 if (ret != LTTNG_OK) {
1492 goto error_unlock;
1493 }
1494 break;
1495 default:
1496 ret = LTTNG_ERR_UNK;
1497 goto error_unlock;
1498 }
1499
1500 kernel_wait_quiescent(kernel_tracer_fd);
1501 break;
1502 }
1503 case LTTNG_DOMAIN_UST:
1504 {
1505 struct ltt_ust_channel *uchan;
1506 struct ltt_ust_session *usess;
1507
1508 usess = session->ust_session;
1509
1510 if (validate_ust_event_name(event_name)) {
1511 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1512 goto error_unlock;
1513 }
1514
1515 /*
1516 * If a non-default channel has been created in the
1517 * session, explicitly require that -c chan_name needs
1518 * to be provided.
1519 */
1520 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1521 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1522 goto error_unlock;
1523 }
1524
1525 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1526 channel_name);
1527 if (uchan == NULL) {
1528 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1529 goto error_unlock;
1530 }
1531
1532 switch (event->type) {
1533 case LTTNG_EVENT_ALL:
1534 /*
1535 * An empty event name means that everything
1536 * should be disabled.
1537 */
1538 if (event->name[0] == '\0') {
1539 ret = event_ust_disable_all_tracepoints(usess, uchan);
1540 } else {
1541 ret = event_ust_disable_tracepoint(usess, uchan,
1542 event_name);
1543 }
1544 if (ret != LTTNG_OK) {
1545 goto error_unlock;
1546 }
1547 break;
1548 default:
1549 ret = LTTNG_ERR_UNK;
1550 goto error_unlock;
1551 }
1552
1553 DBG3("Disable UST event %s in channel %s completed", event_name,
1554 channel_name);
1555 break;
1556 }
1557 case LTTNG_DOMAIN_LOG4J:
1558 case LTTNG_DOMAIN_JUL:
1559 case LTTNG_DOMAIN_PYTHON:
1560 {
1561 struct agent *agt;
1562 struct ltt_ust_session *usess = session->ust_session;
1563
1564 assert(usess);
1565
1566 switch (event->type) {
1567 case LTTNG_EVENT_ALL:
1568 break;
1569 default:
1570 ret = LTTNG_ERR_UNK;
1571 goto error_unlock;
1572 }
1573
1574 agt = trace_ust_find_agent(usess, domain);
1575 if (!agt) {
1576 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1577 goto error_unlock;
1578 }
1579 /*
1580 * An empty event name means that everything
1581 * should be disabled.
1582 */
1583 if (event->name[0] == '\0') {
1584 ret = event_agent_disable_all(usess, agt);
1585 } else {
1586 ret = event_agent_disable(usess, agt, event_name);
1587 }
1588 if (ret != LTTNG_OK) {
1589 goto error_unlock;
1590 }
1591
1592 break;
1593 }
1594 default:
1595 ret = LTTNG_ERR_UND;
1596 goto error_unlock;
1597 }
1598
1599 ret = LTTNG_OK;
1600
1601 error_unlock:
1602 rcu_read_unlock();
1603 error:
1604 return ret;
1605 }
1606
1607 /*
1608 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1609 */
1610 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1611 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1612 {
1613 int ret, chan_kern_created = 0, chan_ust_created = 0;
1614 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1615
1616 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1617 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1618 app_ctx_name = ctx->u.app_ctx.ctx_name;
1619 }
1620
1621 switch (domain) {
1622 case LTTNG_DOMAIN_KERNEL:
1623 assert(session->kernel_session);
1624
1625 if (session->kernel_session->channel_count == 0) {
1626 /* Create default channel */
1627 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1628 if (ret != LTTNG_OK) {
1629 goto error;
1630 }
1631 chan_kern_created = 1;
1632 }
1633 /* Add kernel context to kernel tracer */
1634 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1635 if (ret != LTTNG_OK) {
1636 goto error;
1637 }
1638 break;
1639 case LTTNG_DOMAIN_JUL:
1640 case LTTNG_DOMAIN_LOG4J:
1641 {
1642 /*
1643 * Validate channel name.
1644 * If no channel name is given and the domain is JUL or LOG4J,
1645 * set it to the appropriate domain-specific channel name. If
1646 * a name is provided but does not match the expexted channel
1647 * name, return an error.
1648 */
1649 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1650 strcmp(channel_name,
1651 DEFAULT_JUL_CHANNEL_NAME)) {
1652 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1653 goto error;
1654 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1655 strcmp(channel_name,
1656 DEFAULT_LOG4J_CHANNEL_NAME)) {
1657 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1658 goto error;
1659 }
1660 /* break is _not_ missing here. */
1661 }
1662 case LTTNG_DOMAIN_UST:
1663 {
1664 struct ltt_ust_session *usess = session->ust_session;
1665 unsigned int chan_count;
1666
1667 assert(usess);
1668
1669 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1670 if (chan_count == 0) {
1671 struct lttng_channel *attr;
1672 /* Create default channel */
1673 attr = channel_new_default_attr(domain, usess->buffer_type);
1674 if (attr == NULL) {
1675 ret = LTTNG_ERR_FATAL;
1676 goto error;
1677 }
1678
1679 ret = channel_ust_create(usess, attr, usess->buffer_type);
1680 if (ret != LTTNG_OK) {
1681 free(attr);
1682 goto error;
1683 }
1684 free(attr);
1685 chan_ust_created = 1;
1686 }
1687
1688 ret = context_ust_add(usess, domain, ctx, channel_name);
1689 free(app_ctx_provider_name);
1690 free(app_ctx_name);
1691 app_ctx_name = NULL;
1692 app_ctx_provider_name = NULL;
1693 if (ret != LTTNG_OK) {
1694 goto error;
1695 }
1696 break;
1697 }
1698 default:
1699 ret = LTTNG_ERR_UND;
1700 goto error;
1701 }
1702
1703 ret = LTTNG_OK;
1704 goto end;
1705
1706 error:
1707 if (chan_kern_created) {
1708 struct ltt_kernel_channel *kchan =
1709 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1710 session->kernel_session);
1711 /* Created previously, this should NOT fail. */
1712 assert(kchan);
1713 kernel_destroy_channel(kchan);
1714 }
1715
1716 if (chan_ust_created) {
1717 struct ltt_ust_channel *uchan =
1718 trace_ust_find_channel_by_name(
1719 session->ust_session->domain_global.channels,
1720 DEFAULT_CHANNEL_NAME);
1721 /* Created previously, this should NOT fail. */
1722 assert(uchan);
1723 /* Remove from the channel list of the session. */
1724 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1725 uchan);
1726 trace_ust_destroy_channel(uchan);
1727 }
1728 end:
1729 free(app_ctx_provider_name);
1730 free(app_ctx_name);
1731 return ret;
1732 }
1733
1734 static int validate_event_name(const char *name)
1735 {
1736 int ret = 0;
1737 const char *c = name;
1738 const char *event_name_end = c + LTTNG_SYMBOL_NAME_LEN;
1739 bool null_terminated = false;
1740
1741 /*
1742 * Make sure that unescaped wildcards are only used as the last
1743 * character of the event name.
1744 */
1745 while (c < event_name_end) {
1746 switch (*c) {
1747 case '\0':
1748 null_terminated = true;
1749 goto end;
1750 case '\\':
1751 c++;
1752 break;
1753 case '*':
1754 if ((c + 1) < event_name_end && *(c + 1)) {
1755 /* Wildcard is not the last character */
1756 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1757 goto end;
1758 }
1759 default:
1760 break;
1761 }
1762 c++;
1763 }
1764 end:
1765 if (!ret && !null_terminated) {
1766 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1767 }
1768 return ret;
1769 }
1770
1771 static inline bool name_starts_with(const char *name, const char *prefix)
1772 {
1773 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1774
1775 return !strncmp(name, prefix, max_cmp_len);
1776 }
1777
1778 /* Perform userspace-specific event name validation */
1779 static int validate_ust_event_name(const char *name)
1780 {
1781 int ret = 0;
1782
1783 if (!name) {
1784 ret = -1;
1785 goto end;
1786 }
1787
1788 /*
1789 * Check name against all internal UST event component namespaces used
1790 * by the agents.
1791 */
1792 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1793 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1794 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1795 ret = -1;
1796 }
1797
1798 end:
1799 return ret;
1800 }
1801
1802 /*
1803 * Internal version of cmd_enable_event() with a supplemental
1804 * "internal_event" flag which is used to enable internal events which should
1805 * be hidden from clients. Such events are used in the agent implementation to
1806 * enable the events through which all "agent" events are funeled.
1807 */
1808 static int _cmd_enable_event(struct ltt_session *session,
1809 struct lttng_domain *domain,
1810 char *channel_name, struct lttng_event *event,
1811 char *filter_expression,
1812 struct lttng_filter_bytecode *filter,
1813 struct lttng_event_exclusion *exclusion,
1814 int wpipe, bool internal_event)
1815 {
1816 int ret, channel_created = 0;
1817 struct lttng_channel *attr = NULL;
1818
1819 assert(session);
1820 assert(event);
1821 assert(channel_name);
1822
1823 /* If we have a filter, we must have its filter expression */
1824 assert(!(!!filter_expression ^ !!filter));
1825
1826 DBG("Enable event command for event \'%s\'", event->name);
1827
1828 rcu_read_lock();
1829
1830 ret = validate_event_name(event->name);
1831 if (ret) {
1832 goto error;
1833 }
1834
1835 switch (domain->type) {
1836 case LTTNG_DOMAIN_KERNEL:
1837 {
1838 struct ltt_kernel_channel *kchan;
1839
1840 /*
1841 * If a non-default channel has been created in the
1842 * session, explicitely require that -c chan_name needs
1843 * to be provided.
1844 */
1845 if (session->kernel_session->has_non_default_channel
1846 && channel_name[0] == '\0') {
1847 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1848 goto error;
1849 }
1850
1851 kchan = trace_kernel_get_channel_by_name(channel_name,
1852 session->kernel_session);
1853 if (kchan == NULL) {
1854 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1855 LTTNG_BUFFER_GLOBAL);
1856 if (attr == NULL) {
1857 ret = LTTNG_ERR_FATAL;
1858 goto error;
1859 }
1860 if (lttng_strncpy(attr->name, channel_name,
1861 sizeof(attr->name))) {
1862 ret = LTTNG_ERR_INVALID;
1863 goto error;
1864 }
1865
1866 ret = cmd_enable_channel(session, domain, attr, wpipe);
1867 if (ret != LTTNG_OK) {
1868 goto error;
1869 }
1870 channel_created = 1;
1871 }
1872
1873 /* Get the newly created kernel channel pointer */
1874 kchan = trace_kernel_get_channel_by_name(channel_name,
1875 session->kernel_session);
1876 if (kchan == NULL) {
1877 /* This sould not happen... */
1878 ret = LTTNG_ERR_FATAL;
1879 goto error;
1880 }
1881
1882 switch (event->type) {
1883 case LTTNG_EVENT_ALL:
1884 {
1885 char *filter_expression_a = NULL;
1886 struct lttng_filter_bytecode *filter_a = NULL;
1887
1888 /*
1889 * We need to duplicate filter_expression and filter,
1890 * because ownership is passed to first enable
1891 * event.
1892 */
1893 if (filter_expression) {
1894 filter_expression_a = strdup(filter_expression);
1895 if (!filter_expression_a) {
1896 ret = LTTNG_ERR_FATAL;
1897 goto error;
1898 }
1899 }
1900 if (filter) {
1901 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
1902 if (!filter_a) {
1903 free(filter_expression_a);
1904 ret = LTTNG_ERR_FATAL;
1905 goto error;
1906 }
1907 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
1908 }
1909 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
1910 ret = event_kernel_enable_event(kchan, event,
1911 filter_expression, filter);
1912 /* We have passed ownership */
1913 filter_expression = NULL;
1914 filter = NULL;
1915 if (ret != LTTNG_OK) {
1916 if (channel_created) {
1917 /* Let's not leak a useless channel. */
1918 kernel_destroy_channel(kchan);
1919 }
1920 free(filter_expression_a);
1921 free(filter_a);
1922 goto error;
1923 }
1924 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
1925 ret = event_kernel_enable_event(kchan, event,
1926 filter_expression_a, filter_a);
1927 /* We have passed ownership */
1928 filter_expression_a = NULL;
1929 filter_a = NULL;
1930 if (ret != LTTNG_OK) {
1931 goto error;
1932 }
1933 break;
1934 }
1935 case LTTNG_EVENT_PROBE:
1936 case LTTNG_EVENT_FUNCTION:
1937 case LTTNG_EVENT_FUNCTION_ENTRY:
1938 case LTTNG_EVENT_TRACEPOINT:
1939 ret = event_kernel_enable_event(kchan, event,
1940 filter_expression, filter);
1941 /* We have passed ownership */
1942 filter_expression = NULL;
1943 filter = NULL;
1944 if (ret != LTTNG_OK) {
1945 if (channel_created) {
1946 /* Let's not leak a useless channel. */
1947 kernel_destroy_channel(kchan);
1948 }
1949 goto error;
1950 }
1951 break;
1952 case LTTNG_EVENT_SYSCALL:
1953 ret = event_kernel_enable_event(kchan, event,
1954 filter_expression, filter);
1955 /* We have passed ownership */
1956 filter_expression = NULL;
1957 filter = NULL;
1958 if (ret != LTTNG_OK) {
1959 goto error;
1960 }
1961 break;
1962 default:
1963 ret = LTTNG_ERR_UNK;
1964 goto error;
1965 }
1966
1967 kernel_wait_quiescent(kernel_tracer_fd);
1968 break;
1969 }
1970 case LTTNG_DOMAIN_UST:
1971 {
1972 struct ltt_ust_channel *uchan;
1973 struct ltt_ust_session *usess = session->ust_session;
1974
1975 assert(usess);
1976
1977 /*
1978 * If a non-default channel has been created in the
1979 * session, explicitely require that -c chan_name needs
1980 * to be provided.
1981 */
1982 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1983 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1984 goto error;
1985 }
1986
1987 /* Get channel from global UST domain */
1988 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1989 channel_name);
1990 if (uchan == NULL) {
1991 /* Create default channel */
1992 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1993 usess->buffer_type);
1994 if (attr == NULL) {
1995 ret = LTTNG_ERR_FATAL;
1996 goto error;
1997 }
1998 if (lttng_strncpy(attr->name, channel_name,
1999 sizeof(attr->name))) {
2000 ret = LTTNG_ERR_INVALID;
2001 goto error;
2002 }
2003
2004 ret = cmd_enable_channel(session, domain, attr, wpipe);
2005 if (ret != LTTNG_OK) {
2006 goto error;
2007 }
2008
2009 /* Get the newly created channel reference back */
2010 uchan = trace_ust_find_channel_by_name(
2011 usess->domain_global.channels, channel_name);
2012 assert(uchan);
2013 }
2014
2015 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2016 /*
2017 * Don't allow users to add UST events to channels which
2018 * are assigned to a userspace subdomain (JUL, Log4J,
2019 * Python, etc.).
2020 */
2021 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2022 goto error;
2023 }
2024
2025 if (!internal_event) {
2026 /*
2027 * Ensure the event name is not reserved for internal
2028 * use.
2029 */
2030 ret = validate_ust_event_name(event->name);
2031 if (ret) {
2032 WARN("Userspace event name %s failed validation.",
2033 event->name ?
2034 event->name : "NULL");
2035 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2036 goto error;
2037 }
2038 }
2039
2040 /* At this point, the session and channel exist on the tracer */
2041 ret = event_ust_enable_tracepoint(usess, uchan, event,
2042 filter_expression, filter, exclusion,
2043 internal_event);
2044 /* We have passed ownership */
2045 filter_expression = NULL;
2046 filter = NULL;
2047 exclusion = NULL;
2048 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2049 goto already_enabled;
2050 } else if (ret != LTTNG_OK) {
2051 goto error;
2052 }
2053 break;
2054 }
2055 case LTTNG_DOMAIN_LOG4J:
2056 case LTTNG_DOMAIN_JUL:
2057 case LTTNG_DOMAIN_PYTHON:
2058 {
2059 const char *default_event_name, *default_chan_name;
2060 struct agent *agt;
2061 struct lttng_event uevent;
2062 struct lttng_domain tmp_dom;
2063 struct ltt_ust_session *usess = session->ust_session;
2064
2065 assert(usess);
2066
2067 agt = trace_ust_find_agent(usess, domain->type);
2068 if (!agt) {
2069 agt = agent_create(domain->type);
2070 if (!agt) {
2071 ret = LTTNG_ERR_NOMEM;
2072 goto error;
2073 }
2074 agent_add(agt, usess->agents);
2075 }
2076
2077 /* Create the default tracepoint. */
2078 memset(&uevent, 0, sizeof(uevent));
2079 uevent.type = LTTNG_EVENT_TRACEPOINT;
2080 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2081 default_event_name = event_get_default_agent_ust_name(
2082 domain->type);
2083 if (!default_event_name) {
2084 ret = LTTNG_ERR_FATAL;
2085 goto error;
2086 }
2087 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2088 uevent.name[sizeof(uevent.name) - 1] = '\0';
2089
2090 /*
2091 * The domain type is changed because we are about to enable the
2092 * default channel and event for the JUL domain that are hardcoded.
2093 * This happens in the UST domain.
2094 */
2095 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2096 tmp_dom.type = LTTNG_DOMAIN_UST;
2097
2098 switch (domain->type) {
2099 case LTTNG_DOMAIN_LOG4J:
2100 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2101 break;
2102 case LTTNG_DOMAIN_JUL:
2103 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2104 break;
2105 case LTTNG_DOMAIN_PYTHON:
2106 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2107 break;
2108 default:
2109 /* The switch/case we are in makes this impossible */
2110 assert(0);
2111 }
2112
2113 {
2114 char *filter_expression_copy = NULL;
2115 struct lttng_filter_bytecode *filter_copy = NULL;
2116
2117 if (filter) {
2118 const size_t filter_size = sizeof(
2119 struct lttng_filter_bytecode)
2120 + filter->len;
2121
2122 filter_copy = zmalloc(filter_size);
2123 if (!filter_copy) {
2124 ret = LTTNG_ERR_NOMEM;
2125 goto error;
2126 }
2127 memcpy(filter_copy, filter, filter_size);
2128
2129 filter_expression_copy =
2130 strdup(filter_expression);
2131 if (!filter_expression) {
2132 ret = LTTNG_ERR_NOMEM;
2133 }
2134
2135 if (!filter_expression_copy || !filter_copy) {
2136 free(filter_expression_copy);
2137 free(filter_copy);
2138 goto error;
2139 }
2140 }
2141
2142 ret = cmd_enable_event_internal(session, &tmp_dom,
2143 (char *) default_chan_name,
2144 &uevent, filter_expression_copy,
2145 filter_copy, NULL, wpipe);
2146 }
2147
2148 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2149 goto already_enabled;
2150 } else if (ret != LTTNG_OK) {
2151 goto error;
2152 }
2153
2154 /* The wild card * means that everything should be enabled. */
2155 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2156 ret = event_agent_enable_all(usess, agt, event, filter,
2157 filter_expression);
2158 } else {
2159 ret = event_agent_enable(usess, agt, event, filter,
2160 filter_expression);
2161 }
2162 filter = NULL;
2163 filter_expression = NULL;
2164 if (ret != LTTNG_OK) {
2165 goto error;
2166 }
2167
2168 break;
2169 }
2170 default:
2171 ret = LTTNG_ERR_UND;
2172 goto error;
2173 }
2174
2175 ret = LTTNG_OK;
2176
2177 already_enabled:
2178 error:
2179 free(filter_expression);
2180 free(filter);
2181 free(exclusion);
2182 free(attr);
2183 rcu_read_unlock();
2184 return ret;
2185 }
2186
2187 /*
2188 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2189 * We own filter, exclusion, and filter_expression.
2190 */
2191 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
2192 char *channel_name, struct lttng_event *event,
2193 char *filter_expression,
2194 struct lttng_filter_bytecode *filter,
2195 struct lttng_event_exclusion *exclusion,
2196 int wpipe)
2197 {
2198 return _cmd_enable_event(session, domain, channel_name, event,
2199 filter_expression, filter, exclusion, wpipe, false);
2200 }
2201
2202 /*
2203 * Enable an event which is internal to LTTng. An internal should
2204 * never be made visible to clients and are immune to checks such as
2205 * reserved names.
2206 */
2207 static int cmd_enable_event_internal(struct ltt_session *session,
2208 struct lttng_domain *domain,
2209 char *channel_name, struct lttng_event *event,
2210 char *filter_expression,
2211 struct lttng_filter_bytecode *filter,
2212 struct lttng_event_exclusion *exclusion,
2213 int wpipe)
2214 {
2215 return _cmd_enable_event(session, domain, channel_name, event,
2216 filter_expression, filter, exclusion, wpipe, true);
2217 }
2218
2219 /*
2220 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2221 */
2222 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2223 struct lttng_event **events)
2224 {
2225 int ret;
2226 ssize_t nb_events = 0;
2227
2228 switch (domain) {
2229 case LTTNG_DOMAIN_KERNEL:
2230 nb_events = kernel_list_events(kernel_tracer_fd, events);
2231 if (nb_events < 0) {
2232 ret = LTTNG_ERR_KERN_LIST_FAIL;
2233 goto error;
2234 }
2235 break;
2236 case LTTNG_DOMAIN_UST:
2237 nb_events = ust_app_list_events(events);
2238 if (nb_events < 0) {
2239 ret = LTTNG_ERR_UST_LIST_FAIL;
2240 goto error;
2241 }
2242 break;
2243 case LTTNG_DOMAIN_LOG4J:
2244 case LTTNG_DOMAIN_JUL:
2245 case LTTNG_DOMAIN_PYTHON:
2246 nb_events = agent_list_events(events, domain);
2247 if (nb_events < 0) {
2248 ret = LTTNG_ERR_UST_LIST_FAIL;
2249 goto error;
2250 }
2251 break;
2252 default:
2253 ret = LTTNG_ERR_UND;
2254 goto error;
2255 }
2256
2257 return nb_events;
2258
2259 error:
2260 /* Return negative value to differentiate return code */
2261 return -ret;
2262 }
2263
2264 /*
2265 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2266 */
2267 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2268 struct lttng_event_field **fields)
2269 {
2270 int ret;
2271 ssize_t nb_fields = 0;
2272
2273 switch (domain) {
2274 case LTTNG_DOMAIN_UST:
2275 nb_fields = ust_app_list_event_fields(fields);
2276 if (nb_fields < 0) {
2277 ret = LTTNG_ERR_UST_LIST_FAIL;
2278 goto error;
2279 }
2280 break;
2281 case LTTNG_DOMAIN_KERNEL:
2282 default: /* fall-through */
2283 ret = LTTNG_ERR_UND;
2284 goto error;
2285 }
2286
2287 return nb_fields;
2288
2289 error:
2290 /* Return negative value to differentiate return code */
2291 return -ret;
2292 }
2293
2294 ssize_t cmd_list_syscalls(struct lttng_event **events)
2295 {
2296 return syscall_table_list(events);
2297 }
2298
2299 /*
2300 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
2301 *
2302 * Called with session lock held.
2303 */
2304 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
2305 enum lttng_domain_type domain, int32_t **pids)
2306 {
2307 int ret;
2308 ssize_t nr_pids = 0;
2309
2310 switch (domain) {
2311 case LTTNG_DOMAIN_KERNEL:
2312 {
2313 struct ltt_kernel_session *ksess;
2314
2315 ksess = session->kernel_session;
2316 nr_pids = kernel_list_tracker_pids(ksess, pids);
2317 if (nr_pids < 0) {
2318 ret = LTTNG_ERR_KERN_LIST_FAIL;
2319 goto error;
2320 }
2321 break;
2322 }
2323 case LTTNG_DOMAIN_UST:
2324 {
2325 struct ltt_ust_session *usess;
2326
2327 usess = session->ust_session;
2328 nr_pids = trace_ust_list_tracker_pids(usess, pids);
2329 if (nr_pids < 0) {
2330 ret = LTTNG_ERR_UST_LIST_FAIL;
2331 goto error;
2332 }
2333 break;
2334 }
2335 case LTTNG_DOMAIN_LOG4J:
2336 case LTTNG_DOMAIN_JUL:
2337 case LTTNG_DOMAIN_PYTHON:
2338 default:
2339 ret = LTTNG_ERR_UND;
2340 goto error;
2341 }
2342
2343 return nr_pids;
2344
2345 error:
2346 /* Return negative value to differentiate return code */
2347 return -ret;
2348 }
2349
2350 /*
2351 * Command LTTNG_START_TRACE processed by the client thread.
2352 *
2353 * Called with session mutex held.
2354 */
2355 int cmd_start_trace(struct ltt_session *session)
2356 {
2357 int ret;
2358 unsigned long nb_chan = 0;
2359 struct ltt_kernel_session *ksession;
2360 struct ltt_ust_session *usess;
2361
2362 assert(session);
2363
2364 /* Ease our life a bit ;) */
2365 ksession = session->kernel_session;
2366 usess = session->ust_session;
2367
2368 /* Is the session already started? */
2369 if (session->active) {
2370 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2371 goto error;
2372 }
2373
2374 /*
2375 * Starting a session without channel is useless since after that it's not
2376 * possible to enable channel thus inform the client.
2377 */
2378 if (usess && usess->domain_global.channels) {
2379 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2380 }
2381 if (ksession) {
2382 nb_chan += ksession->channel_count;
2383 }
2384 if (!nb_chan) {
2385 ret = LTTNG_ERR_NO_CHANNEL;
2386 goto error;
2387 }
2388
2389 /* Kernel tracing */
2390 if (ksession != NULL) {
2391 ret = start_kernel_session(ksession, kernel_tracer_fd);
2392 if (ret != LTTNG_OK) {
2393 goto error;
2394 }
2395 }
2396
2397 /* Flag session that trace should start automatically */
2398 if (usess) {
2399 /*
2400 * Even though the start trace might fail, flag this session active so
2401 * other application coming in are started by default.
2402 */
2403 usess->active = 1;
2404
2405 ret = ust_app_start_trace_all(usess);
2406 if (ret < 0) {
2407 ret = LTTNG_ERR_UST_START_FAIL;
2408 goto error;
2409 }
2410 }
2411
2412 /* Flag this after a successful start. */
2413 session->has_been_started = 1;
2414 session->active = 1;
2415
2416 ret = LTTNG_OK;
2417
2418 error:
2419 return ret;
2420 }
2421
2422 /*
2423 * Command LTTNG_STOP_TRACE processed by the client thread.
2424 */
2425 int cmd_stop_trace(struct ltt_session *session)
2426 {
2427 int ret;
2428 struct ltt_kernel_channel *kchan;
2429 struct ltt_kernel_session *ksession;
2430 struct ltt_ust_session *usess;
2431
2432 assert(session);
2433
2434 /* Short cut */
2435 ksession = session->kernel_session;
2436 usess = session->ust_session;
2437
2438 /* Session is not active. Skip everythong and inform the client. */
2439 if (!session->active) {
2440 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2441 goto error;
2442 }
2443
2444 /* Kernel tracer */
2445 if (ksession && ksession->active) {
2446 DBG("Stop kernel tracing");
2447
2448 ret = kernel_stop_session(ksession);
2449 if (ret < 0) {
2450 ret = LTTNG_ERR_KERN_STOP_FAIL;
2451 goto error;
2452 }
2453
2454 kernel_wait_quiescent(kernel_tracer_fd);
2455
2456 /* Flush metadata after stopping (if exists) */
2457 if (ksession->metadata_stream_fd >= 0) {
2458 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2459 if (ret < 0) {
2460 ERR("Kernel metadata flush failed");
2461 }
2462 }
2463
2464 /* Flush all buffers after stopping */
2465 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2466 ret = kernel_flush_buffer(kchan);
2467 if (ret < 0) {
2468 ERR("Kernel flush buffer error");
2469 }
2470 }
2471
2472 ksession->active = 0;
2473 }
2474
2475 if (usess && usess->active) {
2476 /*
2477 * Even though the stop trace might fail, flag this session inactive so
2478 * other application coming in are not started by default.
2479 */
2480 usess->active = 0;
2481
2482 ret = ust_app_stop_trace_all(usess);
2483 if (ret < 0) {
2484 ret = LTTNG_ERR_UST_STOP_FAIL;
2485 goto error;
2486 }
2487 }
2488
2489 /* Flag inactive after a successful stop. */
2490 session->active = 0;
2491 ret = LTTNG_OK;
2492
2493 error:
2494 return ret;
2495 }
2496
2497 /*
2498 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2499 */
2500 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2501 struct lttng_uri *uris)
2502 {
2503 int ret, i;
2504 struct ltt_kernel_session *ksess = session->kernel_session;
2505 struct ltt_ust_session *usess = session->ust_session;
2506
2507 assert(session);
2508 assert(uris);
2509 assert(nb_uri > 0);
2510
2511 /* Can't set consumer URI if the session is active. */
2512 if (session->active) {
2513 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2514 goto error;
2515 }
2516
2517 /* Set the "global" consumer URIs */
2518 for (i = 0; i < nb_uri; i++) {
2519 ret = add_uri_to_consumer(session->consumer,
2520 &uris[i], 0, session->name);
2521 if (ret != LTTNG_OK) {
2522 goto error;
2523 }
2524 }
2525
2526 /* Set UST session URIs */
2527 if (session->ust_session) {
2528 for (i = 0; i < nb_uri; i++) {
2529 ret = add_uri_to_consumer(
2530 session->ust_session->consumer,
2531 &uris[i], LTTNG_DOMAIN_UST,
2532 session->name);
2533 if (ret != LTTNG_OK) {
2534 goto error;
2535 }
2536 }
2537 }
2538
2539 /* Set kernel session URIs */
2540 if (session->kernel_session) {
2541 for (i = 0; i < nb_uri; i++) {
2542 ret = add_uri_to_consumer(
2543 session->kernel_session->consumer,
2544 &uris[i], LTTNG_DOMAIN_KERNEL,
2545 session->name);
2546 if (ret != LTTNG_OK) {
2547 goto error;
2548 }
2549 }
2550 }
2551
2552 /*
2553 * Make sure to set the session in output mode after we set URI since a
2554 * session can be created without URL (thus flagged in no output mode).
2555 */
2556 session->output_traces = 1;
2557 if (ksess) {
2558 ksess->output_traces = 1;
2559 }
2560
2561 if (usess) {
2562 usess->output_traces = 1;
2563 }
2564
2565 /* All good! */
2566 ret = LTTNG_OK;
2567
2568 error:
2569 return ret;
2570 }
2571
2572 /*
2573 * Command LTTNG_CREATE_SESSION processed by the client thread.
2574 */
2575 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
2576 size_t nb_uri, lttng_sock_cred *creds, unsigned int live_timer)
2577 {
2578 int ret;
2579 struct ltt_session *session;
2580
2581 assert(name);
2582 assert(creds);
2583
2584 /*
2585 * Verify if the session already exist
2586 *
2587 * XXX: There is no need for the session lock list here since the caller
2588 * (process_client_msg) is holding it. We might want to change that so a
2589 * single command does not lock the entire session list.
2590 */
2591 session = session_find_by_name(name);
2592 if (session != NULL) {
2593 ret = LTTNG_ERR_EXIST_SESS;
2594 goto find_error;
2595 }
2596
2597 /* Create tracing session in the registry */
2598 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
2599 LTTNG_SOCK_GET_GID_CRED(creds));
2600 if (ret != LTTNG_OK) {
2601 goto session_error;
2602 }
2603
2604 /*
2605 * Get the newly created session pointer back
2606 *
2607 * XXX: There is no need for the session lock list here since the caller
2608 * (process_client_msg) is holding it. We might want to change that so a
2609 * single command does not lock the entire session list.
2610 */
2611 session = session_find_by_name(name);
2612 assert(session);
2613
2614 session->live_timer = live_timer;
2615 /* Create default consumer output for the session not yet created. */
2616 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
2617 if (session->consumer == NULL) {
2618 ret = LTTNG_ERR_FATAL;
2619 goto consumer_error;
2620 }
2621
2622 if (uris) {
2623 ret = cmd_set_consumer_uri(session, nb_uri, uris);
2624 if (ret != LTTNG_OK) {
2625 goto consumer_error;
2626 }
2627 session->output_traces = 1;
2628 } else {
2629 session->output_traces = 0;
2630 DBG2("Session %s created with no output", session->name);
2631 }
2632
2633 session->consumer->enabled = 1;
2634
2635 return LTTNG_OK;
2636
2637 consumer_error:
2638 session_destroy(session);
2639 session_error:
2640 find_error:
2641 return ret;
2642 }
2643
2644 /*
2645 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
2646 */
2647 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
2648 size_t nb_uri, lttng_sock_cred *creds)
2649 {
2650 int ret;
2651 struct ltt_session *session;
2652 struct snapshot_output *new_output = NULL;
2653
2654 assert(name);
2655 assert(creds);
2656
2657 /*
2658 * Create session in no output mode with URIs set to NULL. The uris we've
2659 * received are for a default snapshot output if one.
2660 */
2661 ret = cmd_create_session_uri(name, NULL, 0, creds, 0);
2662 if (ret != LTTNG_OK) {
2663 goto error;
2664 }
2665
2666 /* Get the newly created session pointer back. This should NEVER fail. */
2667 session = session_find_by_name(name);
2668 assert(session);
2669
2670 /* Flag session for snapshot mode. */
2671 session->snapshot_mode = 1;
2672
2673 /* Skip snapshot output creation if no URI is given. */
2674 if (nb_uri == 0) {
2675 goto end;
2676 }
2677
2678 new_output = snapshot_output_alloc();
2679 if (!new_output) {
2680 ret = LTTNG_ERR_NOMEM;
2681 goto error_snapshot_alloc;
2682 }
2683
2684 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
2685 uris, nb_uri, session->consumer, new_output, &session->snapshot);
2686 if (ret < 0) {
2687 if (ret == -ENOMEM) {
2688 ret = LTTNG_ERR_NOMEM;
2689 } else {
2690 ret = LTTNG_ERR_INVALID;
2691 }
2692 goto error_snapshot;
2693 }
2694
2695 rcu_read_lock();
2696 snapshot_add_output(&session->snapshot, new_output);
2697 rcu_read_unlock();
2698
2699 end:
2700 return LTTNG_OK;
2701
2702 error_snapshot:
2703 snapshot_output_destroy(new_output);
2704 error_snapshot_alloc:
2705 session_destroy(session);
2706 error:
2707 return ret;
2708 }
2709
2710 /*
2711 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2712 *
2713 * Called with session lock held.
2714 */
2715 int cmd_destroy_session(struct ltt_session *session, int wpipe)
2716 {
2717 int ret;
2718 struct ltt_ust_session *usess;
2719 struct ltt_kernel_session *ksess;
2720
2721 /* Safety net */
2722 assert(session);
2723
2724 usess = session->ust_session;
2725 ksess = session->kernel_session;
2726
2727 /* Clean kernel session teardown */
2728 kernel_destroy_session(ksess);
2729
2730 /* UST session teardown */
2731 if (usess) {
2732 /* Close any relayd session */
2733 consumer_output_send_destroy_relayd(usess->consumer);
2734
2735 /* Destroy every UST application related to this session. */
2736 ret = ust_app_destroy_trace_all(usess);
2737 if (ret) {
2738 ERR("Error in ust_app_destroy_trace_all");
2739 }
2740
2741 /* Clean up the rest. */
2742 trace_ust_destroy_session(usess);
2743 }
2744
2745 /*
2746 * Must notify the kernel thread here to update it's poll set in order to
2747 * remove the channel(s)' fd just destroyed.
2748 */
2749 ret = notify_thread_pipe(wpipe);
2750 if (ret < 0) {
2751 PERROR("write kernel poll pipe");
2752 }
2753
2754 ret = session_destroy(session);
2755
2756 return ret;
2757 }
2758
2759 /*
2760 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2761 */
2762 int cmd_register_consumer(struct ltt_session *session,
2763 enum lttng_domain_type domain, const char *sock_path,
2764 struct consumer_data *cdata)
2765 {
2766 int ret, sock;
2767 struct consumer_socket *socket = NULL;
2768
2769 assert(session);
2770 assert(cdata);
2771 assert(sock_path);
2772
2773 switch (domain) {
2774 case LTTNG_DOMAIN_KERNEL:
2775 {
2776 struct ltt_kernel_session *ksess = session->kernel_session;
2777
2778 assert(ksess);
2779
2780 /* Can't register a consumer if there is already one */
2781 if (ksess->consumer_fds_sent != 0) {
2782 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2783 goto error;
2784 }
2785
2786 sock = lttcomm_connect_unix_sock(sock_path);
2787 if (sock < 0) {
2788 ret = LTTNG_ERR_CONNECT_FAIL;
2789 goto error;
2790 }
2791 cdata->cmd_sock = sock;
2792
2793 socket = consumer_allocate_socket(&cdata->cmd_sock);
2794 if (socket == NULL) {
2795 ret = close(sock);
2796 if (ret < 0) {
2797 PERROR("close register consumer");
2798 }
2799 cdata->cmd_sock = -1;
2800 ret = LTTNG_ERR_FATAL;
2801 goto error;
2802 }
2803
2804 socket->lock = zmalloc(sizeof(pthread_mutex_t));
2805 if (socket->lock == NULL) {
2806 PERROR("zmalloc pthread mutex");
2807 ret = LTTNG_ERR_FATAL;
2808 goto error;
2809 }
2810 pthread_mutex_init(socket->lock, NULL);
2811 socket->registered = 1;
2812
2813 rcu_read_lock();
2814 consumer_add_socket(socket, ksess->consumer);
2815 rcu_read_unlock();
2816
2817 pthread_mutex_lock(&cdata->pid_mutex);
2818 cdata->pid = -1;
2819 pthread_mutex_unlock(&cdata->pid_mutex);
2820
2821 break;
2822 }
2823 default:
2824 /* TODO: Userspace tracing */
2825 ret = LTTNG_ERR_UND;
2826 goto error;
2827 }
2828
2829 return LTTNG_OK;
2830
2831 error:
2832 if (socket) {
2833 consumer_destroy_socket(socket);
2834 }
2835 return ret;
2836 }
2837
2838 /*
2839 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2840 */
2841 ssize_t cmd_list_domains(struct ltt_session *session,
2842 struct lttng_domain **domains)
2843 {
2844 int ret, index = 0;
2845 ssize_t nb_dom = 0;
2846 struct agent *agt;
2847 struct lttng_ht_iter iter;
2848
2849 if (session->kernel_session != NULL) {
2850 DBG3("Listing domains found kernel domain");
2851 nb_dom++;
2852 }
2853
2854 if (session->ust_session != NULL) {
2855 DBG3("Listing domains found UST global domain");
2856 nb_dom++;
2857
2858 rcu_read_lock();
2859 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2860 agt, node.node) {
2861 if (agt->being_used) {
2862 nb_dom++;
2863 }
2864 }
2865 rcu_read_unlock();
2866 }
2867
2868 if (!nb_dom) {
2869 goto end;
2870 }
2871
2872 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2873 if (*domains == NULL) {
2874 ret = LTTNG_ERR_FATAL;
2875 goto error;
2876 }
2877
2878 if (session->kernel_session != NULL) {
2879 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2880
2881 /* Kernel session buffer type is always GLOBAL */
2882 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
2883
2884 index++;
2885 }
2886
2887 if (session->ust_session != NULL) {
2888 (*domains)[index].type = LTTNG_DOMAIN_UST;
2889 (*domains)[index].buf_type = session->ust_session->buffer_type;
2890 index++;
2891
2892 rcu_read_lock();
2893 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2894 agt, node.node) {
2895 if (agt->being_used) {
2896 (*domains)[index].type = agt->domain;
2897 (*domains)[index].buf_type = session->ust_session->buffer_type;
2898 index++;
2899 }
2900 }
2901 rcu_read_unlock();
2902 }
2903 end:
2904 return nb_dom;
2905
2906 error:
2907 /* Return negative value to differentiate return code */
2908 return -ret;
2909 }
2910
2911
2912 /*
2913 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2914 */
2915 ssize_t cmd_list_channels(enum lttng_domain_type domain,
2916 struct ltt_session *session, struct lttng_channel **channels)
2917 {
2918 ssize_t nb_chan = 0, payload_size = 0, ret;
2919
2920 switch (domain) {
2921 case LTTNG_DOMAIN_KERNEL:
2922 if (session->kernel_session != NULL) {
2923 nb_chan = session->kernel_session->channel_count;
2924 }
2925 DBG3("Number of kernel channels %zd", nb_chan);
2926 if (nb_chan <= 0) {
2927 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
2928 goto end;
2929 }
2930 break;
2931 case LTTNG_DOMAIN_UST:
2932 if (session->ust_session != NULL) {
2933 rcu_read_lock();
2934 nb_chan = lttng_ht_get_count(
2935 session->ust_session->domain_global.channels);
2936 rcu_read_unlock();
2937 }
2938 DBG3("Number of UST global channels %zd", nb_chan);
2939 if (nb_chan < 0) {
2940 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
2941 goto end;
2942 }
2943 break;
2944 default:
2945 ret = -LTTNG_ERR_UND;
2946 goto end;
2947 }
2948
2949 if (nb_chan > 0) {
2950 const size_t channel_size = sizeof(struct lttng_channel) +
2951 sizeof(struct lttcomm_channel_extended);
2952 struct lttcomm_channel_extended *channel_exts;
2953
2954 payload_size = nb_chan * channel_size;
2955 *channels = zmalloc(payload_size);
2956 if (*channels == NULL) {
2957 ret = -LTTNG_ERR_FATAL;
2958 goto end;
2959 }
2960
2961 channel_exts = ((void *) *channels) +
2962 (nb_chan * sizeof(struct lttng_channel));
2963 ret = list_lttng_channels(domain, session, *channels, channel_exts);
2964 if (ret != LTTNG_OK) {
2965 free(*channels);
2966 *channels = NULL;
2967 goto end;
2968 }
2969 } else {
2970 *channels = NULL;
2971 }
2972
2973 ret = payload_size;
2974 end:
2975 return ret;
2976 }
2977
2978 /*
2979 * Command LTTNG_LIST_EVENTS processed by the client thread.
2980 */
2981 ssize_t cmd_list_events(enum lttng_domain_type domain,
2982 struct ltt_session *session, char *channel_name,
2983 struct lttng_event **events, size_t *total_size)
2984 {
2985 int ret = 0;
2986 ssize_t nb_event = 0;
2987
2988 switch (domain) {
2989 case LTTNG_DOMAIN_KERNEL:
2990 if (session->kernel_session != NULL) {
2991 nb_event = list_lttng_kernel_events(channel_name,
2992 session->kernel_session, events,
2993 total_size);
2994 }
2995 break;
2996 case LTTNG_DOMAIN_UST:
2997 {
2998 if (session->ust_session != NULL) {
2999 nb_event = list_lttng_ust_global_events(channel_name,
3000 &session->ust_session->domain_global, events,
3001 total_size);
3002 }
3003 break;
3004 }
3005 case LTTNG_DOMAIN_LOG4J:
3006 case LTTNG_DOMAIN_JUL:
3007 case LTTNG_DOMAIN_PYTHON:
3008 if (session->ust_session) {
3009 struct lttng_ht_iter iter;
3010 struct agent *agt;
3011
3012 rcu_read_lock();
3013 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3014 &iter.iter, agt, node.node) {
3015 if (agt->domain == domain) {
3016 nb_event = list_lttng_agent_events(
3017 agt, events,
3018 total_size);
3019 break;
3020 }
3021 }
3022 rcu_read_unlock();
3023 }
3024 break;
3025 default:
3026 ret = LTTNG_ERR_UND;
3027 goto error;
3028 }
3029
3030 return nb_event;
3031
3032 error:
3033 /* Return negative value to differentiate return code */
3034 return -ret;
3035 }
3036
3037 /*
3038 * Using the session list, filled a lttng_session array to send back to the
3039 * client for session listing.
3040 *
3041 * The session list lock MUST be acquired before calling this function. Use
3042 * session_lock_list() and session_unlock_list().
3043 */
3044 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
3045 gid_t gid)
3046 {
3047 int ret;
3048 unsigned int i = 0;
3049 struct ltt_session *session;
3050 struct ltt_session_list *list = session_get_list();
3051
3052 DBG("Getting all available session for UID %d GID %d",
3053 uid, gid);
3054 /*
3055 * Iterate over session list and append data after the control struct in
3056 * the buffer.
3057 */
3058 cds_list_for_each_entry(session, &list->head, list) {
3059 /*
3060 * Only list the sessions the user can control.
3061 */
3062 if (!session_access_ok(session, uid, gid)) {
3063 continue;
3064 }
3065
3066 struct ltt_kernel_session *ksess = session->kernel_session;
3067 struct ltt_ust_session *usess = session->ust_session;
3068
3069 if (session->consumer->type == CONSUMER_DST_NET ||
3070 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3071 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3072 ret = build_network_session_path(sessions[i].path,
3073 sizeof(sessions[i].path), session);
3074 } else {
3075 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3076 session->consumer->dst.trace_path);
3077 }
3078 if (ret < 0) {
3079 PERROR("snprintf session path");
3080 continue;
3081 }
3082
3083 strncpy(sessions[i].name, session->name, NAME_MAX);
3084 sessions[i].name[NAME_MAX - 1] = '\0';
3085 sessions[i].enabled = session->active;
3086 sessions[i].snapshot_mode = session->snapshot_mode;
3087 sessions[i].live_timer_interval = session->live_timer;
3088 i++;
3089 }
3090 }
3091
3092 /*
3093 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3094 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3095 */
3096 int cmd_data_pending(struct ltt_session *session)
3097 {
3098 int ret;
3099 struct ltt_kernel_session *ksess = session->kernel_session;
3100 struct ltt_ust_session *usess = session->ust_session;
3101
3102 assert(session);
3103
3104 /* Session MUST be stopped to ask for data availability. */
3105 if (session->active) {
3106 ret = LTTNG_ERR_SESSION_STARTED;
3107 goto error;
3108 } else {
3109 /*
3110 * If stopped, just make sure we've started before else the above call
3111 * will always send that there is data pending.
3112 *
3113 * The consumer assumes that when the data pending command is received,
3114 * the trace has been started before or else no output data is written
3115 * by the streams which is a condition for data pending. So, this is
3116 * *VERY* important that we don't ask the consumer before a start
3117 * trace.
3118 */
3119 if (!session->has_been_started) {
3120 ret = 0;
3121 goto error;
3122 }
3123 }
3124
3125 if (ksess && ksess->consumer) {
3126 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3127 if (ret == 1) {
3128 /* Data is still being extracted for the kernel. */
3129 goto error;
3130 }
3131 }
3132
3133 if (usess && usess->consumer) {
3134 ret = consumer_is_data_pending(usess->id, usess->consumer);
3135 if (ret == 1) {
3136 /* Data is still being extracted for the kernel. */
3137 goto error;
3138 }
3139 }
3140
3141 /* Data is ready to be read by a viewer */
3142 ret = 0;
3143
3144 error:
3145 return ret;
3146 }
3147
3148 /*
3149 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3150 *
3151 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3152 */
3153 int cmd_snapshot_add_output(struct ltt_session *session,
3154 struct lttng_snapshot_output *output, uint32_t *id)
3155 {
3156 int ret;
3157 struct snapshot_output *new_output;
3158
3159 assert(session);
3160 assert(output);
3161
3162 DBG("Cmd snapshot add output for session %s", session->name);
3163
3164 /*
3165 * Can't create an output if the session is not set in no-output mode.
3166 */
3167 if (session->output_traces) {
3168 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3169 goto error;
3170 }
3171
3172 /* Only one output is allowed until we have the "tee" feature. */
3173 if (session->snapshot.nb_output == 1) {
3174 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3175 goto error;
3176 }
3177
3178 new_output = snapshot_output_alloc();
3179 if (!new_output) {
3180 ret = LTTNG_ERR_NOMEM;
3181 goto error;
3182 }
3183
3184 ret = snapshot_output_init(output->max_size, output->name,
3185 output->ctrl_url, output->data_url, session->consumer, new_output,
3186 &session->snapshot);
3187 if (ret < 0) {
3188 if (ret == -ENOMEM) {
3189 ret = LTTNG_ERR_NOMEM;
3190 } else {
3191 ret = LTTNG_ERR_INVALID;
3192 }
3193 goto free_error;
3194 }
3195
3196 rcu_read_lock();
3197 snapshot_add_output(&session->snapshot, new_output);
3198 if (id) {
3199 *id = new_output->id;
3200 }
3201 rcu_read_unlock();
3202
3203 return LTTNG_OK;
3204
3205 free_error:
3206 snapshot_output_destroy(new_output);
3207 error:
3208 return ret;
3209 }
3210
3211 /*
3212 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3213 *
3214 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3215 */
3216 int cmd_snapshot_del_output(struct ltt_session *session,
3217 struct lttng_snapshot_output *output)
3218 {
3219 int ret;
3220 struct snapshot_output *sout = NULL;
3221
3222 assert(session);
3223 assert(output);
3224
3225 rcu_read_lock();
3226
3227 /*
3228 * Permission denied to create an output if the session is not
3229 * set in no output mode.
3230 */
3231 if (session->output_traces) {
3232 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3233 goto error;
3234 }
3235
3236 if (output->id) {
3237 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
3238 session->name);
3239 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
3240 } else if (*output->name != '\0') {
3241 DBG("Cmd snapshot del output name %s for session %s", output->name,
3242 session->name);
3243 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
3244 }
3245 if (!sout) {
3246 ret = LTTNG_ERR_INVALID;
3247 goto error;
3248 }
3249
3250 snapshot_delete_output(&session->snapshot, sout);
3251 snapshot_output_destroy(sout);
3252 ret = LTTNG_OK;
3253
3254 error:
3255 rcu_read_unlock();
3256 return ret;
3257 }
3258
3259 /*
3260 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
3261 *
3262 * If no output is available, outputs is untouched and 0 is returned.
3263 *
3264 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
3265 */
3266 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
3267 struct lttng_snapshot_output **outputs)
3268 {
3269 int ret, idx = 0;
3270 struct lttng_snapshot_output *list = NULL;
3271 struct lttng_ht_iter iter;
3272 struct snapshot_output *output;
3273
3274 assert(session);
3275 assert(outputs);
3276
3277 DBG("Cmd snapshot list outputs for session %s", session->name);
3278
3279 /*
3280 * Permission denied to create an output if the session is not
3281 * set in no output mode.
3282 */
3283 if (session->output_traces) {
3284 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3285 goto end;
3286 }
3287
3288 if (session->snapshot.nb_output == 0) {
3289 ret = 0;
3290 goto end;
3291 }
3292
3293 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
3294 if (!list) {
3295 ret = -LTTNG_ERR_NOMEM;
3296 goto end;
3297 }
3298
3299 /* Copy list from session to the new list object. */
3300 rcu_read_lock();
3301 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
3302 output, node.node) {
3303 assert(output->consumer);
3304 list[idx].id = output->id;
3305 list[idx].max_size = output->max_size;
3306 if (lttng_strncpy(list[idx].name, output->name,
3307 sizeof(list[idx].name))) {
3308 ret = -LTTNG_ERR_INVALID;
3309 goto error;
3310 }
3311 if (output->consumer->type == CONSUMER_DST_LOCAL) {
3312 if (lttng_strncpy(list[idx].ctrl_url,
3313 output->consumer->dst.trace_path,
3314 sizeof(list[idx].ctrl_url))) {
3315 ret = -LTTNG_ERR_INVALID;
3316 goto error;
3317 }
3318 } else {
3319 /* Control URI. */
3320 ret = uri_to_str_url(&output->consumer->dst.net.control,
3321 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
3322 if (ret < 0) {
3323 ret = -LTTNG_ERR_NOMEM;
3324 goto error;
3325 }
3326
3327 /* Data URI. */
3328 ret = uri_to_str_url(&output->consumer->dst.net.data,
3329 list[idx].data_url, sizeof(list[idx].data_url));
3330 if (ret < 0) {
3331 ret = -LTTNG_ERR_NOMEM;
3332 goto error;
3333 }
3334 }
3335 idx++;
3336 }
3337
3338 *outputs = list;
3339 list = NULL;
3340 ret = session->snapshot.nb_output;
3341 error:
3342 rcu_read_unlock();
3343 free(list);
3344 end:
3345 return ret;
3346 }
3347
3348 /*
3349 * Check if we can regenerate the metadata for this session.
3350 * Only kernel, UST per-uid and non-live sessions are supported.
3351 *
3352 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
3353 */
3354 static
3355 int check_regenerate_metadata_support(struct ltt_session *session)
3356 {
3357 int ret;
3358
3359 assert(session);
3360
3361 if (session->live_timer != 0) {
3362 ret = LTTNG_ERR_LIVE_SESSION;
3363 goto end;
3364 }
3365 if (!session->active) {
3366 ret = LTTNG_ERR_SESSION_NOT_STARTED;
3367 goto end;
3368 }
3369 if (session->ust_session) {
3370 switch (session->ust_session->buffer_type) {
3371 case LTTNG_BUFFER_PER_UID:
3372 break;
3373 case LTTNG_BUFFER_PER_PID:
3374 ret = LTTNG_ERR_PER_PID_SESSION;
3375 goto end;
3376 default:
3377 assert(0);
3378 ret = LTTNG_ERR_UNK;
3379 goto end;
3380 }
3381 }
3382 if (session->consumer->type == CONSUMER_DST_NET &&
3383 session->consumer->relay_minor_version < 8) {
3384 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
3385 goto end;
3386 }
3387 ret = 0;
3388
3389 end:
3390 return ret;
3391 }
3392
3393 static
3394 int clear_metadata_file(int fd)
3395 {
3396 int ret;
3397
3398 ret = lseek(fd, 0, SEEK_SET);
3399 if (ret < 0) {
3400 PERROR("lseek");
3401 goto end;
3402 }
3403
3404 ret = ftruncate(fd, 0);
3405 if (ret < 0) {
3406 PERROR("ftruncate");
3407 goto end;
3408 }
3409
3410 end:
3411 return ret;
3412 }
3413
3414 static
3415 int ust_regenerate_metadata(struct ltt_ust_session *usess)
3416 {
3417 int ret = 0;
3418 struct buffer_reg_uid *uid_reg = NULL;
3419 struct buffer_reg_session *session_reg = NULL;
3420
3421 rcu_read_lock();
3422 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
3423 struct ust_registry_session *registry;
3424 struct ust_registry_channel *chan;
3425 struct lttng_ht_iter iter_chan;
3426
3427 session_reg = uid_reg->registry;
3428 registry = session_reg->reg.ust;
3429
3430 pthread_mutex_lock(&registry->lock);
3431 registry->metadata_len_sent = 0;
3432 memset(registry->metadata, 0, registry->metadata_alloc_len);
3433 registry->metadata_len = 0;
3434 registry->metadata_version++;
3435 if (registry->metadata_fd > 0) {
3436 /* Clear the metadata file's content. */
3437 ret = clear_metadata_file(registry->metadata_fd);
3438 if (ret) {
3439 pthread_mutex_unlock(&registry->lock);
3440 goto end;
3441 }
3442 }
3443
3444 ret = ust_metadata_session_statedump(registry, NULL,
3445 registry->major, registry->minor);
3446 if (ret) {
3447 pthread_mutex_unlock(&registry->lock);
3448 ERR("Failed to generate session metadata (err = %d)",
3449 ret);
3450 goto end;
3451 }
3452 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
3453 chan, node.node) {
3454 struct ust_registry_event *event;
3455 struct lttng_ht_iter iter_event;
3456
3457 ret = ust_metadata_channel_statedump(registry, chan);
3458 if (ret) {
3459 pthread_mutex_unlock(&registry->lock);
3460 ERR("Failed to generate channel metadata "
3461 "(err = %d)", ret);
3462 goto end;
3463 }
3464 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
3465 event, node.node) {
3466 ret = ust_metadata_event_statedump(registry,
3467 chan, event);
3468 if (ret) {
3469 pthread_mutex_unlock(&registry->lock);
3470 ERR("Failed to generate event metadata "
3471 "(err = %d)", ret);
3472 goto end;
3473 }
3474 }
3475 }
3476 pthread_mutex_unlock(&registry->lock);
3477 }
3478
3479 end:
3480 rcu_read_unlock();
3481 return ret;
3482 }
3483
3484 /*
3485 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
3486 *
3487 * Ask the consumer to truncate the existing metadata file(s) and
3488 * then regenerate the metadata. Live and per-pid sessions are not
3489 * supported and return an error.
3490 *
3491 * Return 0 on success or else a LTTNG_ERR code.
3492 */
3493 int cmd_regenerate_metadata(struct ltt_session *session)
3494 {
3495 int ret;
3496
3497 assert(session);
3498
3499 ret = check_regenerate_metadata_support(session);
3500 if (ret) {
3501 goto end;
3502 }
3503
3504 if (session->kernel_session) {
3505 ret = kernctl_session_regenerate_metadata(
3506 session->kernel_session->fd);
3507 if (ret < 0) {
3508 ERR("Failed to regenerate the kernel metadata");
3509 goto end;
3510 }
3511 }
3512
3513 if (session->ust_session) {
3514 ret = ust_regenerate_metadata(session->ust_session);
3515 if (ret < 0) {
3516 ERR("Failed to regenerate the UST metadata");
3517 goto end;
3518 }
3519 }
3520 DBG("Cmd metadata regenerate for session %s", session->name);
3521 ret = LTTNG_OK;
3522
3523 end:
3524 return ret;
3525 }
3526
3527 /*
3528 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
3529 *
3530 * Ask the tracer to regenerate a new statedump.
3531 *
3532 * Return 0 on success or else a LTTNG_ERR code.
3533 */
3534 int cmd_regenerate_statedump(struct ltt_session *session)
3535 {
3536 int ret;
3537
3538 assert(session);
3539
3540 if (!session->active) {
3541 ret = LTTNG_ERR_SESSION_NOT_STARTED;
3542 goto end;
3543 }
3544 ret = 0;
3545
3546 if (session->kernel_session) {
3547 ret = kernctl_session_regenerate_statedump(
3548 session->kernel_session->fd);
3549 /*
3550 * Currently, the statedump in kernel can only fail if out
3551 * of memory.
3552 */
3553 if (ret < 0) {
3554 if (ret == -ENOMEM) {
3555 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
3556 } else {
3557 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
3558 }
3559 ERR("Failed to regenerate the kernel statedump");
3560 goto end;
3561 }
3562 }
3563
3564 if (session->ust_session) {
3565 ret = ust_app_regenerate_statedump_all(session->ust_session);
3566 /*
3567 * Currently, the statedump in UST always returns 0.
3568 */
3569 if (ret < 0) {
3570 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
3571 ERR("Failed to regenerate the UST statedump");
3572 goto end;
3573 }
3574 }
3575 DBG("Cmd regenerate statedump for session %s", session->name);
3576 ret = LTTNG_OK;
3577
3578 end:
3579 return ret;
3580 }
3581
3582 /*
3583 * Send relayd sockets from snapshot output to consumer. Ignore request if the
3584 * snapshot output is *not* set with a remote destination.
3585 *
3586 * Return 0 on success or a LTTNG_ERR code.
3587 */
3588 static int set_relayd_for_snapshot(struct consumer_output *consumer,
3589 struct snapshot_output *snap_output, struct ltt_session *session)
3590 {
3591 int ret = LTTNG_OK;
3592 struct lttng_ht_iter iter;
3593 struct consumer_socket *socket;
3594
3595 assert(consumer);
3596 assert(snap_output);
3597 assert(session);
3598
3599 DBG2("Set relayd object from snapshot output");
3600
3601 /* Ignore if snapshot consumer output is not network. */
3602 if (snap_output->consumer->type != CONSUMER_DST_NET) {
3603 goto error;
3604 }
3605
3606 /*
3607 * For each consumer socket, create and send the relayd object of the
3608 * snapshot output.
3609 */
3610 rcu_read_lock();
3611 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
3612 socket, node.node) {
3613 ret = send_consumer_relayd_sockets(0, session->id,
3614 snap_output->consumer, socket,
3615 session->name, session->hostname,
3616 session->live_timer);
3617 if (ret != LTTNG_OK) {
3618 rcu_read_unlock();
3619 goto error;
3620 }
3621 }
3622 rcu_read_unlock();
3623
3624 error:
3625 return ret;
3626 }
3627
3628 /*
3629 * Record a kernel snapshot.
3630 *
3631 * Return LTTNG_OK on success or a LTTNG_ERR code.
3632 */
3633 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
3634 struct snapshot_output *output, struct ltt_session *session,
3635 int wait, uint64_t nb_packets_per_stream)
3636 {
3637 int ret;
3638
3639 assert(ksess);
3640 assert(output);
3641 assert(session);
3642
3643
3644 /*
3645 * Copy kernel session sockets so we can communicate with the right
3646 * consumer for the snapshot record command.
3647 */
3648 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
3649 if (ret < 0) {
3650 ret = LTTNG_ERR_NOMEM;
3651 goto error;
3652 }
3653
3654 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
3655 if (ret != LTTNG_OK) {
3656 goto error_snapshot;
3657 }
3658
3659 ret = kernel_snapshot_record(ksess, output, wait, nb_packets_per_stream);
3660 if (ret != LTTNG_OK) {
3661 goto error_snapshot;
3662 }
3663
3664 ret = LTTNG_OK;
3665 goto end;
3666
3667 error_snapshot:
3668 /* Clean up copied sockets so this output can use some other later on. */
3669 consumer_destroy_output_sockets(output->consumer);
3670 error:
3671 end:
3672 return ret;
3673 }
3674
3675 /*
3676 * Record a UST snapshot.
3677 *
3678 * Return 0 on success or a LTTNG_ERR error code.
3679 */
3680 static int record_ust_snapshot(struct ltt_ust_session *usess,
3681 struct snapshot_output *output, struct ltt_session *session,
3682 int wait, uint64_t nb_packets_per_stream)
3683 {
3684 int ret;
3685
3686 assert(usess);
3687 assert(output);
3688 assert(session);
3689
3690 /*
3691 * Copy UST session sockets so we can communicate with the right
3692 * consumer for the snapshot record command.
3693 */
3694 ret = consumer_copy_sockets(output->consumer, usess->consumer);
3695 if (ret < 0) {
3696 ret = LTTNG_ERR_NOMEM;
3697 goto error;
3698 }
3699
3700 ret = set_relayd_for_snapshot(usess->consumer, output, session);
3701 if (ret != LTTNG_OK) {
3702 goto error_snapshot;
3703 }
3704
3705 ret = ust_app_snapshot_record(usess, output, wait, nb_packets_per_stream);
3706 if (ret < 0) {
3707 switch (-ret) {
3708 case EINVAL:
3709 ret = LTTNG_ERR_INVALID;
3710 break;
3711 default:
3712 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3713 break;
3714 }
3715 goto error_snapshot;
3716 }
3717
3718 ret = LTTNG_OK;
3719
3720 error_snapshot:
3721 /* Clean up copied sockets so this output can use some other later on. */
3722 consumer_destroy_output_sockets(output->consumer);
3723 error:
3724 return ret;
3725 }
3726
3727 static
3728 uint64_t get_session_size_one_more_packet_per_stream(struct ltt_session *session,
3729 uint64_t cur_nr_packets)
3730 {
3731 uint64_t tot_size = 0;
3732
3733 if (session->kernel_session) {
3734 struct ltt_kernel_channel *chan;
3735 struct ltt_kernel_session *ksess = session->kernel_session;
3736
3737 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
3738 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
3739 /*
3740 * Don't take channel into account if we
3741 * already grab all its packets.
3742 */
3743 continue;
3744 }
3745 tot_size += chan->channel->attr.subbuf_size
3746 * chan->stream_count;
3747 }
3748 }
3749
3750 if (session->ust_session) {
3751 struct ltt_ust_session *usess = session->ust_session;
3752
3753 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
3754 cur_nr_packets);
3755 }
3756
3757 return tot_size;
3758 }
3759
3760 /*
3761 * Calculate the number of packets we can grab from each stream that
3762 * fits within the overall snapshot max size.
3763 *
3764 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
3765 * the number of packets per stream.
3766 *
3767 * TODO: this approach is not perfect: we consider the worse case
3768 * (packet filling the sub-buffers) as an upper bound, but we could do
3769 * better if we do this calculation while we actually grab the packet
3770 * content: we would know how much padding we don't actually store into
3771 * the file.
3772 *
3773 * This algorithm is currently bounded by the number of packets per
3774 * stream.
3775 *
3776 * Since we call this algorithm before actually grabbing the data, it's
3777 * an approximation: for instance, applications could appear/disappear
3778 * in between this call and actually grabbing data.
3779 */
3780 static
3781 int64_t get_session_nb_packets_per_stream(struct ltt_session *session, uint64_t max_size)
3782 {
3783 int64_t size_left;
3784 uint64_t cur_nb_packets = 0;
3785
3786 if (!max_size) {
3787 return 0; /* Infinite */
3788 }
3789
3790 size_left = max_size;
3791 for (;;) {
3792 uint64_t one_more_packet_tot_size;
3793
3794 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(session,
3795 cur_nb_packets);
3796 if (!one_more_packet_tot_size) {
3797 /* We are already grabbing all packets. */
3798 break;
3799 }
3800 size_left -= one_more_packet_tot_size;
3801 if (size_left < 0) {
3802 break;
3803 }
3804 cur_nb_packets++;
3805 }
3806 if (!cur_nb_packets) {
3807 /* Not enough room to grab one packet of each stream, error. */
3808 return -1;
3809 }
3810 return cur_nb_packets;
3811 }
3812
3813 /*
3814 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
3815 *
3816 * The wait parameter is ignored so this call always wait for the snapshot to
3817 * complete before returning.
3818 *
3819 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3820 */
3821 int cmd_snapshot_record(struct ltt_session *session,
3822 struct lttng_snapshot_output *output, int wait)
3823 {
3824 int ret = LTTNG_OK;
3825 unsigned int use_tmp_output = 0;
3826 struct snapshot_output tmp_output;
3827 unsigned int snapshot_success = 0;
3828 char datetime[16];
3829
3830 assert(session);
3831 assert(output);
3832
3833 DBG("Cmd snapshot record for session %s", session->name);
3834
3835 /* Get the datetime for the snapshot output directory. */
3836 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
3837 sizeof(datetime));
3838 if (!ret) {
3839 ret = LTTNG_ERR_INVALID;
3840 goto error;
3841 }
3842
3843 /*
3844 * Permission denied to create an output if the session is not
3845 * set in no output mode.
3846 */
3847 if (session->output_traces) {
3848 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3849 goto error;
3850 }
3851
3852 /* The session needs to be started at least once. */
3853 if (!session->has_been_started) {
3854 ret = LTTNG_ERR_START_SESSION_ONCE;
3855 goto error;
3856 }
3857
3858 /* Use temporary output for the session. */
3859 if (*output->ctrl_url != '\0') {
3860 ret = snapshot_output_init(output->max_size, output->name,
3861 output->ctrl_url, output->data_url, session->consumer,
3862 &tmp_output, NULL);
3863 if (ret < 0) {
3864 if (ret == -ENOMEM) {
3865 ret = LTTNG_ERR_NOMEM;
3866 } else {
3867 ret = LTTNG_ERR_INVALID;
3868 }
3869 goto error;
3870 }
3871 /* Use the global session count for the temporary snapshot. */
3872 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3873
3874 /* Use the global datetime */
3875 memcpy(tmp_output.datetime, datetime, sizeof(datetime));
3876 use_tmp_output = 1;
3877 }
3878
3879 if (use_tmp_output) {
3880 int64_t nb_packets_per_stream;
3881
3882 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3883 tmp_output.max_size);
3884 if (nb_packets_per_stream < 0) {
3885 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3886 goto error;
3887 }
3888
3889 if (session->kernel_session) {
3890 ret = record_kernel_snapshot(session->kernel_session,
3891 &tmp_output, session,
3892 wait, nb_packets_per_stream);
3893 if (ret != LTTNG_OK) {
3894 goto error;
3895 }
3896 }
3897
3898 if (session->ust_session) {
3899 ret = record_ust_snapshot(session->ust_session,
3900 &tmp_output, session,
3901 wait, nb_packets_per_stream);
3902 if (ret != LTTNG_OK) {
3903 goto error;
3904 }
3905 }
3906
3907 snapshot_success = 1;
3908 } else {
3909 struct snapshot_output *sout;
3910 struct lttng_ht_iter iter;
3911
3912 rcu_read_lock();
3913 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3914 &iter.iter, sout, node.node) {
3915 int64_t nb_packets_per_stream;
3916
3917 /*
3918 * Make a local copy of the output and assign the possible
3919 * temporary value given by the caller.
3920 */
3921 memset(&tmp_output, 0, sizeof(tmp_output));
3922 memcpy(&tmp_output, sout, sizeof(tmp_output));
3923
3924 if (output->max_size != (uint64_t) -1ULL) {
3925 tmp_output.max_size = output->max_size;
3926 }
3927
3928 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3929 tmp_output.max_size);
3930 if (nb_packets_per_stream < 0) {
3931 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3932 rcu_read_unlock();
3933 goto error;
3934 }
3935
3936 /* Use temporary name. */
3937 if (*output->name != '\0') {
3938 if (lttng_strncpy(tmp_output.name, output->name,
3939 sizeof(tmp_output.name))) {
3940 ret = LTTNG_ERR_INVALID;
3941 rcu_read_unlock();
3942 goto error;
3943 }
3944 }
3945
3946 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3947 memcpy(tmp_output.datetime, datetime, sizeof(datetime));
3948
3949 if (session->kernel_session) {
3950 ret = record_kernel_snapshot(session->kernel_session,
3951 &tmp_output, session,
3952 wait, nb_packets_per_stream);
3953 if (ret != LTTNG_OK) {
3954 rcu_read_unlock();
3955 goto error;
3956 }
3957 }
3958
3959 if (session->ust_session) {
3960 ret = record_ust_snapshot(session->ust_session,
3961 &tmp_output, session,
3962 wait, nb_packets_per_stream);
3963 if (ret != LTTNG_OK) {
3964 rcu_read_unlock();
3965 goto error;
3966 }
3967 }
3968 snapshot_success = 1;
3969 }
3970 rcu_read_unlock();
3971 }
3972
3973 if (snapshot_success) {
3974 session->snapshot.nb_snapshot++;
3975 } else {
3976 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3977 }
3978
3979 error:
3980 return ret;
3981 }
3982
3983 /*
3984 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
3985 */
3986 int cmd_set_session_shm_path(struct ltt_session *session,
3987 const char *shm_path)
3988 {
3989 /* Safety net */
3990 assert(session);
3991
3992 /*
3993 * Can only set shm path before session is started.
3994 */
3995 if (session->has_been_started) {
3996 return LTTNG_ERR_SESSION_STARTED;
3997 }
3998
3999 strncpy(session->shm_path, shm_path,
4000 sizeof(session->shm_path));
4001 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
4002
4003 return 0;
4004 }
4005
4006 /*
4007 * Init command subsystem.
4008 */
4009 void cmd_init(void)
4010 {
4011 /*
4012 * Set network sequence index to 1 for streams to match a relayd
4013 * socket on the consumer side.
4014 */
4015 pthread_mutex_lock(&relayd_net_seq_idx_lock);
4016 relayd_net_seq_idx = 1;
4017 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
4018
4019 DBG("Command subsystem initialized");
4020 }
LTTng 2.0 tools and control repository
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