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Fix: use off_t type for lseek function return value to avoid overflow
[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 == LTTNG_ERR_RELAYD_VERSION_FAIL) {
860 goto close_sock;
861 } else if (ret < 0) {
862 ERR("Unable to reach lttng-relayd");
863 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
864 goto close_sock;
865 }
866 consumer->relay_major_version = rsock->major;
867 consumer->relay_minor_version = rsock->minor;
868 } else if (uri->stype == LTTNG_STREAM_DATA) {
869 DBG3("Creating relayd data socket from URI");
870 } else {
871 /* Command is not valid */
872 ERR("Relayd invalid stream type: %d", uri->stype);
873 ret = LTTNG_ERR_INVALID;
874 goto close_sock;
875 }
876
877 *relayd_sock = rsock;
878
879 return LTTNG_OK;
880
881 close_sock:
882 /* The returned value is not useful since we are on an error path. */
883 (void) relayd_close(rsock);
884 free_sock:
885 free(rsock);
886 error:
887 return ret;
888 }
889
890 /*
891 * Connect to the relayd using URI and send the socket to the right consumer.
892 *
893 * The consumer socket lock must be held by the caller.
894 */
895 static int send_consumer_relayd_socket(enum lttng_domain_type domain,
896 unsigned int session_id, struct lttng_uri *relayd_uri,
897 struct consumer_output *consumer,
898 struct consumer_socket *consumer_sock,
899 char *session_name, char *hostname, int session_live_timer)
900 {
901 int ret;
902 struct lttcomm_relayd_sock *rsock = NULL;
903
904 /* Connect to relayd and make version check if uri is the control. */
905 ret = create_connect_relayd(relayd_uri, &rsock, consumer);
906 if (ret != LTTNG_OK) {
907 goto relayd_comm_error;
908 }
909 assert(rsock);
910
911 /* Set the network sequence index if not set. */
912 if (consumer->net_seq_index == (uint64_t) -1ULL) {
913 pthread_mutex_lock(&relayd_net_seq_idx_lock);
914 /*
915 * Increment net_seq_idx because we are about to transfer the
916 * new relayd socket to the consumer.
917 * Assign unique key so the consumer can match streams.
918 */
919 consumer->net_seq_index = ++relayd_net_seq_idx;
920 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
921 }
922
923 /* Send relayd socket to consumer. */
924 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
925 relayd_uri->stype, session_id,
926 session_name, hostname, session_live_timer);
927 if (ret < 0) {
928 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
929 goto close_sock;
930 }
931
932 /* Flag that the corresponding socket was sent. */
933 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
934 consumer_sock->control_sock_sent = 1;
935 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
936 consumer_sock->data_sock_sent = 1;
937 }
938
939 ret = LTTNG_OK;
940
941 /*
942 * Close socket which was dup on the consumer side. The session daemon does
943 * NOT keep track of the relayd socket(s) once transfer to the consumer.
944 */
945
946 close_sock:
947 if (ret != LTTNG_OK) {
948 /*
949 * The consumer output for this session should not be used anymore
950 * since the relayd connection failed thus making any tracing or/and
951 * streaming not usable.
952 */
953 consumer->enabled = 0;
954 }
955 (void) relayd_close(rsock);
956 free(rsock);
957
958 relayd_comm_error:
959 return ret;
960 }
961
962 /*
963 * Send both relayd sockets to a specific consumer and domain. This is a
964 * helper function to facilitate sending the information to the consumer for a
965 * session.
966 *
967 * The consumer socket lock must be held by the caller.
968 */
969 static int send_consumer_relayd_sockets(enum lttng_domain_type domain,
970 unsigned int session_id, struct consumer_output *consumer,
971 struct consumer_socket *sock, char *session_name,
972 char *hostname, int session_live_timer)
973 {
974 int ret = LTTNG_OK;
975
976 assert(consumer);
977 assert(sock);
978
979 /* Sending control relayd socket. */
980 if (!sock->control_sock_sent) {
981 ret = send_consumer_relayd_socket(domain, session_id,
982 &consumer->dst.net.control, consumer, sock,
983 session_name, hostname, session_live_timer);
984 if (ret != LTTNG_OK) {
985 goto error;
986 }
987 }
988
989 /* Sending data relayd socket. */
990 if (!sock->data_sock_sent) {
991 ret = send_consumer_relayd_socket(domain, session_id,
992 &consumer->dst.net.data, consumer, sock,
993 session_name, hostname, session_live_timer);
994 if (ret != LTTNG_OK) {
995 goto error;
996 }
997 }
998
999 error:
1000 return ret;
1001 }
1002
1003 /*
1004 * Setup relayd connections for a tracing session. First creates the socket to
1005 * the relayd and send them to the right domain consumer. Consumer type MUST be
1006 * network.
1007 */
1008 int cmd_setup_relayd(struct ltt_session *session)
1009 {
1010 int ret = LTTNG_OK;
1011 struct ltt_ust_session *usess;
1012 struct ltt_kernel_session *ksess;
1013 struct consumer_socket *socket;
1014 struct lttng_ht_iter iter;
1015
1016 assert(session);
1017
1018 usess = session->ust_session;
1019 ksess = session->kernel_session;
1020
1021 DBG("Setting relayd for session %s", session->name);
1022
1023 rcu_read_lock();
1024
1025 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1026 && usess->consumer->enabled) {
1027 /* For each consumer socket, send relayd sockets */
1028 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1029 socket, node.node) {
1030 pthread_mutex_lock(socket->lock);
1031 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1032 usess->consumer, socket,
1033 session->name, session->hostname,
1034 session->live_timer);
1035 pthread_mutex_unlock(socket->lock);
1036 if (ret != LTTNG_OK) {
1037 goto error;
1038 }
1039 /* Session is now ready for network streaming. */
1040 session->net_handle = 1;
1041 }
1042 session->consumer->relay_major_version =
1043 usess->consumer->relay_major_version;
1044 session->consumer->relay_minor_version =
1045 usess->consumer->relay_minor_version;
1046 }
1047
1048 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1049 && ksess->consumer->enabled) {
1050 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1051 socket, node.node) {
1052 pthread_mutex_lock(socket->lock);
1053 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1054 ksess->consumer, socket,
1055 session->name, session->hostname,
1056 session->live_timer);
1057 pthread_mutex_unlock(socket->lock);
1058 if (ret != LTTNG_OK) {
1059 goto error;
1060 }
1061 /* Session is now ready for network streaming. */
1062 session->net_handle = 1;
1063 }
1064 session->consumer->relay_major_version =
1065 ksess->consumer->relay_major_version;
1066 session->consumer->relay_minor_version =
1067 ksess->consumer->relay_minor_version;
1068 }
1069
1070 error:
1071 rcu_read_unlock();
1072 return ret;
1073 }
1074
1075 /*
1076 * Start a kernel session by opening all necessary streams.
1077 */
1078 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
1079 {
1080 int ret;
1081 struct ltt_kernel_channel *kchan;
1082
1083 /* Open kernel metadata */
1084 if (ksess->metadata == NULL && ksess->output_traces) {
1085 ret = kernel_open_metadata(ksess);
1086 if (ret < 0) {
1087 ret = LTTNG_ERR_KERN_META_FAIL;
1088 goto error;
1089 }
1090 }
1091
1092 /* Open kernel metadata stream */
1093 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1094 ret = kernel_open_metadata_stream(ksess);
1095 if (ret < 0) {
1096 ERR("Kernel create metadata stream failed");
1097 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1098 goto error;
1099 }
1100 }
1101
1102 /* For each channel */
1103 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1104 if (kchan->stream_count == 0) {
1105 ret = kernel_open_channel_stream(kchan);
1106 if (ret < 0) {
1107 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1108 goto error;
1109 }
1110 /* Update the stream global counter */
1111 ksess->stream_count_global += ret;
1112 }
1113 }
1114
1115 /* Setup kernel consumer socket and send fds to it */
1116 ret = init_kernel_tracing(ksess);
1117 if (ret != 0) {
1118 ret = LTTNG_ERR_KERN_START_FAIL;
1119 goto error;
1120 }
1121
1122 /* This start the kernel tracing */
1123 ret = kernel_start_session(ksess);
1124 if (ret < 0) {
1125 ret = LTTNG_ERR_KERN_START_FAIL;
1126 goto error;
1127 }
1128
1129 /* Quiescent wait after starting trace */
1130 kernel_wait_quiescent(kernel_tracer_fd);
1131
1132 ksess->active = 1;
1133
1134 ret = LTTNG_OK;
1135
1136 error:
1137 return ret;
1138 }
1139
1140 /*
1141 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1142 */
1143 int cmd_disable_channel(struct ltt_session *session,
1144 enum lttng_domain_type domain, char *channel_name)
1145 {
1146 int ret;
1147 struct ltt_ust_session *usess;
1148
1149 usess = session->ust_session;
1150
1151 rcu_read_lock();
1152
1153 switch (domain) {
1154 case LTTNG_DOMAIN_KERNEL:
1155 {
1156 ret = channel_kernel_disable(session->kernel_session,
1157 channel_name);
1158 if (ret != LTTNG_OK) {
1159 goto error;
1160 }
1161
1162 kernel_wait_quiescent(kernel_tracer_fd);
1163 break;
1164 }
1165 case LTTNG_DOMAIN_UST:
1166 {
1167 struct ltt_ust_channel *uchan;
1168 struct lttng_ht *chan_ht;
1169
1170 chan_ht = usess->domain_global.channels;
1171
1172 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1173 if (uchan == NULL) {
1174 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1175 goto error;
1176 }
1177
1178 ret = channel_ust_disable(usess, uchan);
1179 if (ret != LTTNG_OK) {
1180 goto error;
1181 }
1182 break;
1183 }
1184 default:
1185 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1186 goto error;
1187 }
1188
1189 ret = LTTNG_OK;
1190
1191 error:
1192 rcu_read_unlock();
1193 return ret;
1194 }
1195
1196 /*
1197 * Command LTTNG_TRACK_PID processed by the client thread.
1198 *
1199 * Called with session lock held.
1200 */
1201 int cmd_track_pid(struct ltt_session *session, enum lttng_domain_type domain,
1202 int pid)
1203 {
1204 int ret;
1205
1206 rcu_read_lock();
1207
1208 switch (domain) {
1209 case LTTNG_DOMAIN_KERNEL:
1210 {
1211 struct ltt_kernel_session *ksess;
1212
1213 ksess = session->kernel_session;
1214
1215 ret = kernel_track_pid(ksess, pid);
1216 if (ret != LTTNG_OK) {
1217 goto error;
1218 }
1219
1220 kernel_wait_quiescent(kernel_tracer_fd);
1221 break;
1222 }
1223 case LTTNG_DOMAIN_UST:
1224 {
1225 struct ltt_ust_session *usess;
1226
1227 usess = session->ust_session;
1228
1229 ret = trace_ust_track_pid(usess, pid);
1230 if (ret != LTTNG_OK) {
1231 goto error;
1232 }
1233 break;
1234 }
1235 default:
1236 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1237 goto error;
1238 }
1239
1240 ret = LTTNG_OK;
1241
1242 error:
1243 rcu_read_unlock();
1244 return ret;
1245 }
1246
1247 /*
1248 * Command LTTNG_UNTRACK_PID processed by the client thread.
1249 *
1250 * Called with session lock held.
1251 */
1252 int cmd_untrack_pid(struct ltt_session *session, enum lttng_domain_type domain,
1253 int pid)
1254 {
1255 int ret;
1256
1257 rcu_read_lock();
1258
1259 switch (domain) {
1260 case LTTNG_DOMAIN_KERNEL:
1261 {
1262 struct ltt_kernel_session *ksess;
1263
1264 ksess = session->kernel_session;
1265
1266 ret = kernel_untrack_pid(ksess, pid);
1267 if (ret != LTTNG_OK) {
1268 goto error;
1269 }
1270
1271 kernel_wait_quiescent(kernel_tracer_fd);
1272 break;
1273 }
1274 case LTTNG_DOMAIN_UST:
1275 {
1276 struct ltt_ust_session *usess;
1277
1278 usess = session->ust_session;
1279
1280 ret = trace_ust_untrack_pid(usess, pid);
1281 if (ret != LTTNG_OK) {
1282 goto error;
1283 }
1284 break;
1285 }
1286 default:
1287 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1288 goto error;
1289 }
1290
1291 ret = LTTNG_OK;
1292
1293 error:
1294 rcu_read_unlock();
1295 return ret;
1296 }
1297
1298 /*
1299 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1300 *
1301 * The wpipe arguments is used as a notifier for the kernel thread.
1302 */
1303 int cmd_enable_channel(struct ltt_session *session,
1304 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1305 {
1306 int ret;
1307 struct ltt_ust_session *usess = session->ust_session;
1308 struct lttng_ht *chan_ht;
1309 size_t len;
1310
1311 assert(session);
1312 assert(attr);
1313 assert(domain);
1314
1315 len = lttng_strnlen(attr->name, sizeof(attr->name));
1316
1317 /* Validate channel name */
1318 if (attr->name[0] == '.' ||
1319 memchr(attr->name, '/', len) != NULL) {
1320 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1321 goto end;
1322 }
1323
1324 DBG("Enabling channel %s for session %s", attr->name, session->name);
1325
1326 rcu_read_lock();
1327
1328 /*
1329 * Don't try to enable a channel if the session has been started at
1330 * some point in time before. The tracer does not allow it.
1331 */
1332 if (session->has_been_started) {
1333 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1334 goto error;
1335 }
1336
1337 /*
1338 * If the session is a live session, remove the switch timer, the
1339 * live timer does the same thing but sends also synchronisation
1340 * beacons for inactive streams.
1341 */
1342 if (session->live_timer > 0) {
1343 attr->attr.live_timer_interval = session->live_timer;
1344 attr->attr.switch_timer_interval = 0;
1345 }
1346
1347 switch (domain->type) {
1348 case LTTNG_DOMAIN_KERNEL:
1349 {
1350 struct ltt_kernel_channel *kchan;
1351
1352 kchan = trace_kernel_get_channel_by_name(attr->name,
1353 session->kernel_session);
1354 if (kchan == NULL) {
1355 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1356 if (attr->name[0] != '\0') {
1357 session->kernel_session->has_non_default_channel = 1;
1358 }
1359 } else {
1360 ret = channel_kernel_enable(session->kernel_session, kchan);
1361 }
1362
1363 if (ret != LTTNG_OK) {
1364 goto error;
1365 }
1366
1367 kernel_wait_quiescent(kernel_tracer_fd);
1368 break;
1369 }
1370 case LTTNG_DOMAIN_UST:
1371 case LTTNG_DOMAIN_JUL:
1372 case LTTNG_DOMAIN_LOG4J:
1373 case LTTNG_DOMAIN_PYTHON:
1374 {
1375 struct ltt_ust_channel *uchan;
1376
1377 /*
1378 * FIXME
1379 *
1380 * Current agent implementation limitations force us to allow
1381 * only one channel at once in "agent" subdomains. Each
1382 * subdomain has a default channel name which must be strictly
1383 * adhered to.
1384 */
1385 if (domain->type == LTTNG_DOMAIN_JUL) {
1386 if (strncmp(attr->name, DEFAULT_JUL_CHANNEL_NAME,
1387 LTTNG_SYMBOL_NAME_LEN)) {
1388 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1389 goto error;
1390 }
1391 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1392 if (strncmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME,
1393 LTTNG_SYMBOL_NAME_LEN)) {
1394 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1395 goto error;
1396 }
1397 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1398 if (strncmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME,
1399 LTTNG_SYMBOL_NAME_LEN)) {
1400 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1401 goto error;
1402 }
1403 }
1404
1405 chan_ht = usess->domain_global.channels;
1406
1407 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1408 if (uchan == NULL) {
1409 ret = channel_ust_create(usess, attr, domain->buf_type);
1410 if (attr->name[0] != '\0') {
1411 usess->has_non_default_channel = 1;
1412 }
1413 } else {
1414 ret = channel_ust_enable(usess, uchan);
1415 }
1416 break;
1417 }
1418 default:
1419 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1420 goto error;
1421 }
1422
1423 error:
1424 rcu_read_unlock();
1425 end:
1426 return ret;
1427 }
1428
1429 /*
1430 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1431 */
1432 int cmd_disable_event(struct ltt_session *session,
1433 enum lttng_domain_type domain, char *channel_name,
1434 struct lttng_event *event)
1435 {
1436 int ret;
1437 char *event_name;
1438
1439 DBG("Disable event command for event \'%s\'", event->name);
1440
1441 event_name = event->name;
1442 if (validate_event_name(event_name)) {
1443 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1444 goto error;
1445 }
1446
1447 /* Error out on unhandled search criteria */
1448 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1449 || event->pid || event->filter || event->exclusion) {
1450 ret = LTTNG_ERR_UNK;
1451 goto error;
1452 }
1453
1454 rcu_read_lock();
1455
1456 switch (domain) {
1457 case LTTNG_DOMAIN_KERNEL:
1458 {
1459 struct ltt_kernel_channel *kchan;
1460 struct ltt_kernel_session *ksess;
1461
1462 ksess = session->kernel_session;
1463
1464 /*
1465 * If a non-default channel has been created in the
1466 * session, explicitely require that -c chan_name needs
1467 * to be provided.
1468 */
1469 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1470 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1471 goto error_unlock;
1472 }
1473
1474 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1475 if (kchan == NULL) {
1476 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1477 goto error_unlock;
1478 }
1479
1480 switch (event->type) {
1481 case LTTNG_EVENT_ALL:
1482 case LTTNG_EVENT_TRACEPOINT:
1483 case LTTNG_EVENT_SYSCALL:
1484 case LTTNG_EVENT_PROBE:
1485 case LTTNG_EVENT_FUNCTION:
1486 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1487 if (event_name[0] == '\0') {
1488 ret = event_kernel_disable_event(kchan,
1489 NULL, event->type);
1490 } else {
1491 ret = event_kernel_disable_event(kchan,
1492 event_name, event->type);
1493 }
1494 if (ret != LTTNG_OK) {
1495 goto error_unlock;
1496 }
1497 break;
1498 default:
1499 ret = LTTNG_ERR_UNK;
1500 goto error_unlock;
1501 }
1502
1503 kernel_wait_quiescent(kernel_tracer_fd);
1504 break;
1505 }
1506 case LTTNG_DOMAIN_UST:
1507 {
1508 struct ltt_ust_channel *uchan;
1509 struct ltt_ust_session *usess;
1510
1511 usess = session->ust_session;
1512
1513 if (validate_ust_event_name(event_name)) {
1514 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1515 goto error_unlock;
1516 }
1517
1518 /*
1519 * If a non-default channel has been created in the
1520 * session, explicitly require that -c chan_name needs
1521 * to be provided.
1522 */
1523 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1524 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1525 goto error_unlock;
1526 }
1527
1528 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1529 channel_name);
1530 if (uchan == NULL) {
1531 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1532 goto error_unlock;
1533 }
1534
1535 switch (event->type) {
1536 case LTTNG_EVENT_ALL:
1537 /*
1538 * An empty event name means that everything
1539 * should be disabled.
1540 */
1541 if (event->name[0] == '\0') {
1542 ret = event_ust_disable_all_tracepoints(usess, uchan);
1543 } else {
1544 ret = event_ust_disable_tracepoint(usess, uchan,
1545 event_name);
1546 }
1547 if (ret != LTTNG_OK) {
1548 goto error_unlock;
1549 }
1550 break;
1551 default:
1552 ret = LTTNG_ERR_UNK;
1553 goto error_unlock;
1554 }
1555
1556 DBG3("Disable UST event %s in channel %s completed", event_name,
1557 channel_name);
1558 break;
1559 }
1560 case LTTNG_DOMAIN_LOG4J:
1561 case LTTNG_DOMAIN_JUL:
1562 case LTTNG_DOMAIN_PYTHON:
1563 {
1564 struct agent *agt;
1565 struct ltt_ust_session *usess = session->ust_session;
1566
1567 assert(usess);
1568
1569 switch (event->type) {
1570 case LTTNG_EVENT_ALL:
1571 break;
1572 default:
1573 ret = LTTNG_ERR_UNK;
1574 goto error_unlock;
1575 }
1576
1577 agt = trace_ust_find_agent(usess, domain);
1578 if (!agt) {
1579 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1580 goto error_unlock;
1581 }
1582 /*
1583 * An empty event name means that everything
1584 * should be disabled.
1585 */
1586 if (event->name[0] == '\0') {
1587 ret = event_agent_disable_all(usess, agt);
1588 } else {
1589 ret = event_agent_disable(usess, agt, event_name);
1590 }
1591 if (ret != LTTNG_OK) {
1592 goto error_unlock;
1593 }
1594
1595 break;
1596 }
1597 default:
1598 ret = LTTNG_ERR_UND;
1599 goto error_unlock;
1600 }
1601
1602 ret = LTTNG_OK;
1603
1604 error_unlock:
1605 rcu_read_unlock();
1606 error:
1607 return ret;
1608 }
1609
1610 /*
1611 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1612 */
1613 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1614 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1615 {
1616 int ret, chan_kern_created = 0, chan_ust_created = 0;
1617 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1618
1619 /*
1620 * Don't try to add a context if the session has been started at
1621 * some point in time before. The tracer does not allow it and would
1622 * result in a corrupted trace.
1623 */
1624 if (session->has_been_started) {
1625 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1626 goto end;
1627 }
1628
1629 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1630 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1631 app_ctx_name = ctx->u.app_ctx.ctx_name;
1632 }
1633
1634 switch (domain) {
1635 case LTTNG_DOMAIN_KERNEL:
1636 assert(session->kernel_session);
1637
1638 if (session->kernel_session->channel_count == 0) {
1639 /* Create default channel */
1640 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1641 if (ret != LTTNG_OK) {
1642 goto error;
1643 }
1644 chan_kern_created = 1;
1645 }
1646 /* Add kernel context to kernel tracer */
1647 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1648 if (ret != LTTNG_OK) {
1649 goto error;
1650 }
1651 break;
1652 case LTTNG_DOMAIN_JUL:
1653 case LTTNG_DOMAIN_LOG4J:
1654 {
1655 /*
1656 * Validate channel name.
1657 * If no channel name is given and the domain is JUL or LOG4J,
1658 * set it to the appropriate domain-specific channel name. If
1659 * a name is provided but does not match the expexted channel
1660 * name, return an error.
1661 */
1662 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1663 strcmp(channel_name,
1664 DEFAULT_JUL_CHANNEL_NAME)) {
1665 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1666 goto error;
1667 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1668 strcmp(channel_name,
1669 DEFAULT_LOG4J_CHANNEL_NAME)) {
1670 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1671 goto error;
1672 }
1673 /* break is _not_ missing here. */
1674 }
1675 case LTTNG_DOMAIN_UST:
1676 {
1677 struct ltt_ust_session *usess = session->ust_session;
1678 unsigned int chan_count;
1679
1680 assert(usess);
1681
1682 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1683 if (chan_count == 0) {
1684 struct lttng_channel *attr;
1685 /* Create default channel */
1686 attr = channel_new_default_attr(domain, usess->buffer_type);
1687 if (attr == NULL) {
1688 ret = LTTNG_ERR_FATAL;
1689 goto error;
1690 }
1691
1692 ret = channel_ust_create(usess, attr, usess->buffer_type);
1693 if (ret != LTTNG_OK) {
1694 free(attr);
1695 goto error;
1696 }
1697 free(attr);
1698 chan_ust_created = 1;
1699 }
1700
1701 ret = context_ust_add(usess, domain, ctx, channel_name);
1702 free(app_ctx_provider_name);
1703 free(app_ctx_name);
1704 app_ctx_name = NULL;
1705 app_ctx_provider_name = NULL;
1706 if (ret != LTTNG_OK) {
1707 goto error;
1708 }
1709 break;
1710 }
1711 default:
1712 ret = LTTNG_ERR_UND;
1713 goto error;
1714 }
1715
1716 ret = LTTNG_OK;
1717 goto end;
1718
1719 error:
1720 if (chan_kern_created) {
1721 struct ltt_kernel_channel *kchan =
1722 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1723 session->kernel_session);
1724 /* Created previously, this should NOT fail. */
1725 assert(kchan);
1726 kernel_destroy_channel(kchan);
1727 }
1728
1729 if (chan_ust_created) {
1730 struct ltt_ust_channel *uchan =
1731 trace_ust_find_channel_by_name(
1732 session->ust_session->domain_global.channels,
1733 DEFAULT_CHANNEL_NAME);
1734 /* Created previously, this should NOT fail. */
1735 assert(uchan);
1736 /* Remove from the channel list of the session. */
1737 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1738 uchan);
1739 trace_ust_destroy_channel(uchan);
1740 }
1741 end:
1742 free(app_ctx_provider_name);
1743 free(app_ctx_name);
1744 return ret;
1745 }
1746
1747 static int validate_event_name(const char *name)
1748 {
1749 int ret = 0;
1750 const char *c = name;
1751 const char *event_name_end = c + LTTNG_SYMBOL_NAME_LEN;
1752 bool null_terminated = false;
1753
1754 /*
1755 * Make sure that unescaped wildcards are only used as the last
1756 * character of the event name.
1757 */
1758 while (c < event_name_end) {
1759 switch (*c) {
1760 case '\0':
1761 null_terminated = true;
1762 goto end;
1763 case '\\':
1764 c++;
1765 break;
1766 case '*':
1767 if ((c + 1) < event_name_end && *(c + 1)) {
1768 /* Wildcard is not the last character */
1769 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1770 goto end;
1771 }
1772 default:
1773 break;
1774 }
1775 c++;
1776 }
1777 end:
1778 if (!ret && !null_terminated) {
1779 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1780 }
1781 return ret;
1782 }
1783
1784 static inline bool name_starts_with(const char *name, const char *prefix)
1785 {
1786 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1787
1788 return !strncmp(name, prefix, max_cmp_len);
1789 }
1790
1791 /* Perform userspace-specific event name validation */
1792 static int validate_ust_event_name(const char *name)
1793 {
1794 int ret = 0;
1795
1796 if (!name) {
1797 ret = -1;
1798 goto end;
1799 }
1800
1801 /*
1802 * Check name against all internal UST event component namespaces used
1803 * by the agents.
1804 */
1805 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1806 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1807 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1808 ret = -1;
1809 }
1810
1811 end:
1812 return ret;
1813 }
1814
1815 /*
1816 * Internal version of cmd_enable_event() with a supplemental
1817 * "internal_event" flag which is used to enable internal events which should
1818 * be hidden from clients. Such events are used in the agent implementation to
1819 * enable the events through which all "agent" events are funeled.
1820 */
1821 static int _cmd_enable_event(struct ltt_session *session,
1822 struct lttng_domain *domain,
1823 char *channel_name, struct lttng_event *event,
1824 char *filter_expression,
1825 struct lttng_filter_bytecode *filter,
1826 struct lttng_event_exclusion *exclusion,
1827 int wpipe, bool internal_event)
1828 {
1829 int ret, channel_created = 0;
1830 struct lttng_channel *attr = NULL;
1831
1832 assert(session);
1833 assert(event);
1834 assert(channel_name);
1835
1836 /* If we have a filter, we must have its filter expression */
1837 assert(!(!!filter_expression ^ !!filter));
1838
1839 DBG("Enable event command for event \'%s\'", event->name);
1840
1841 rcu_read_lock();
1842
1843 ret = validate_event_name(event->name);
1844 if (ret) {
1845 goto error;
1846 }
1847
1848 switch (domain->type) {
1849 case LTTNG_DOMAIN_KERNEL:
1850 {
1851 struct ltt_kernel_channel *kchan;
1852
1853 /*
1854 * If a non-default channel has been created in the
1855 * session, explicitely require that -c chan_name needs
1856 * to be provided.
1857 */
1858 if (session->kernel_session->has_non_default_channel
1859 && channel_name[0] == '\0') {
1860 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1861 goto error;
1862 }
1863
1864 kchan = trace_kernel_get_channel_by_name(channel_name,
1865 session->kernel_session);
1866 if (kchan == NULL) {
1867 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1868 LTTNG_BUFFER_GLOBAL);
1869 if (attr == NULL) {
1870 ret = LTTNG_ERR_FATAL;
1871 goto error;
1872 }
1873 if (lttng_strncpy(attr->name, channel_name,
1874 sizeof(attr->name))) {
1875 ret = LTTNG_ERR_INVALID;
1876 goto error;
1877 }
1878
1879 ret = cmd_enable_channel(session, domain, attr, wpipe);
1880 if (ret != LTTNG_OK) {
1881 goto error;
1882 }
1883 channel_created = 1;
1884 }
1885
1886 /* Get the newly created kernel channel pointer */
1887 kchan = trace_kernel_get_channel_by_name(channel_name,
1888 session->kernel_session);
1889 if (kchan == NULL) {
1890 /* This sould not happen... */
1891 ret = LTTNG_ERR_FATAL;
1892 goto error;
1893 }
1894
1895 switch (event->type) {
1896 case LTTNG_EVENT_ALL:
1897 {
1898 char *filter_expression_a = NULL;
1899 struct lttng_filter_bytecode *filter_a = NULL;
1900
1901 /*
1902 * We need to duplicate filter_expression and filter,
1903 * because ownership is passed to first enable
1904 * event.
1905 */
1906 if (filter_expression) {
1907 filter_expression_a = strdup(filter_expression);
1908 if (!filter_expression_a) {
1909 ret = LTTNG_ERR_FATAL;
1910 goto error;
1911 }
1912 }
1913 if (filter) {
1914 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
1915 if (!filter_a) {
1916 free(filter_expression_a);
1917 ret = LTTNG_ERR_FATAL;
1918 goto error;
1919 }
1920 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
1921 }
1922 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
1923 ret = event_kernel_enable_event(kchan, event,
1924 filter_expression, filter);
1925 /* We have passed ownership */
1926 filter_expression = NULL;
1927 filter = NULL;
1928 if (ret != LTTNG_OK) {
1929 if (channel_created) {
1930 /* Let's not leak a useless channel. */
1931 kernel_destroy_channel(kchan);
1932 }
1933 free(filter_expression_a);
1934 free(filter_a);
1935 goto error;
1936 }
1937 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
1938 ret = event_kernel_enable_event(kchan, event,
1939 filter_expression_a, filter_a);
1940 /* We have passed ownership */
1941 filter_expression_a = NULL;
1942 filter_a = NULL;
1943 if (ret != LTTNG_OK) {
1944 goto error;
1945 }
1946 break;
1947 }
1948 case LTTNG_EVENT_PROBE:
1949 case LTTNG_EVENT_FUNCTION:
1950 case LTTNG_EVENT_FUNCTION_ENTRY:
1951 case LTTNG_EVENT_TRACEPOINT:
1952 ret = event_kernel_enable_event(kchan, event,
1953 filter_expression, filter);
1954 /* We have passed ownership */
1955 filter_expression = NULL;
1956 filter = NULL;
1957 if (ret != LTTNG_OK) {
1958 if (channel_created) {
1959 /* Let's not leak a useless channel. */
1960 kernel_destroy_channel(kchan);
1961 }
1962 goto error;
1963 }
1964 break;
1965 case LTTNG_EVENT_SYSCALL:
1966 ret = event_kernel_enable_event(kchan, event,
1967 filter_expression, filter);
1968 /* We have passed ownership */
1969 filter_expression = NULL;
1970 filter = NULL;
1971 if (ret != LTTNG_OK) {
1972 goto error;
1973 }
1974 break;
1975 default:
1976 ret = LTTNG_ERR_UNK;
1977 goto error;
1978 }
1979
1980 kernel_wait_quiescent(kernel_tracer_fd);
1981 break;
1982 }
1983 case LTTNG_DOMAIN_UST:
1984 {
1985 struct ltt_ust_channel *uchan;
1986 struct ltt_ust_session *usess = session->ust_session;
1987
1988 assert(usess);
1989
1990 /*
1991 * If a non-default channel has been created in the
1992 * session, explicitely require that -c chan_name needs
1993 * to be provided.
1994 */
1995 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1996 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1997 goto error;
1998 }
1999
2000 /* Get channel from global UST domain */
2001 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2002 channel_name);
2003 if (uchan == NULL) {
2004 /* Create default channel */
2005 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
2006 usess->buffer_type);
2007 if (attr == NULL) {
2008 ret = LTTNG_ERR_FATAL;
2009 goto error;
2010 }
2011 if (lttng_strncpy(attr->name, channel_name,
2012 sizeof(attr->name))) {
2013 ret = LTTNG_ERR_INVALID;
2014 goto error;
2015 }
2016
2017 ret = cmd_enable_channel(session, domain, attr, wpipe);
2018 if (ret != LTTNG_OK) {
2019 goto error;
2020 }
2021
2022 /* Get the newly created channel reference back */
2023 uchan = trace_ust_find_channel_by_name(
2024 usess->domain_global.channels, channel_name);
2025 assert(uchan);
2026 }
2027
2028 if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
2029 /*
2030 * Don't allow users to add UST events to channels which
2031 * are assigned to a userspace subdomain (JUL, Log4J,
2032 * Python, etc.).
2033 */
2034 ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
2035 goto error;
2036 }
2037
2038 if (!internal_event) {
2039 /*
2040 * Ensure the event name is not reserved for internal
2041 * use.
2042 */
2043 ret = validate_ust_event_name(event->name);
2044 if (ret) {
2045 WARN("Userspace event name %s failed validation.",
2046 event->name ?
2047 event->name : "NULL");
2048 ret = LTTNG_ERR_INVALID_EVENT_NAME;
2049 goto error;
2050 }
2051 }
2052
2053 /* At this point, the session and channel exist on the tracer */
2054 ret = event_ust_enable_tracepoint(usess, uchan, event,
2055 filter_expression, filter, exclusion,
2056 internal_event);
2057 /* We have passed ownership */
2058 filter_expression = NULL;
2059 filter = NULL;
2060 exclusion = NULL;
2061 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2062 goto already_enabled;
2063 } else if (ret != LTTNG_OK) {
2064 goto error;
2065 }
2066 break;
2067 }
2068 case LTTNG_DOMAIN_LOG4J:
2069 case LTTNG_DOMAIN_JUL:
2070 case LTTNG_DOMAIN_PYTHON:
2071 {
2072 const char *default_event_name, *default_chan_name;
2073 struct agent *agt;
2074 struct lttng_event uevent;
2075 struct lttng_domain tmp_dom;
2076 struct ltt_ust_session *usess = session->ust_session;
2077
2078 assert(usess);
2079
2080 agt = trace_ust_find_agent(usess, domain->type);
2081 if (!agt) {
2082 agt = agent_create(domain->type);
2083 if (!agt) {
2084 ret = LTTNG_ERR_NOMEM;
2085 goto error;
2086 }
2087 agent_add(agt, usess->agents);
2088 }
2089
2090 /* Create the default tracepoint. */
2091 memset(&uevent, 0, sizeof(uevent));
2092 uevent.type = LTTNG_EVENT_TRACEPOINT;
2093 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2094 default_event_name = event_get_default_agent_ust_name(
2095 domain->type);
2096 if (!default_event_name) {
2097 ret = LTTNG_ERR_FATAL;
2098 goto error;
2099 }
2100 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
2101 uevent.name[sizeof(uevent.name) - 1] = '\0';
2102
2103 /*
2104 * The domain type is changed because we are about to enable the
2105 * default channel and event for the JUL domain that are hardcoded.
2106 * This happens in the UST domain.
2107 */
2108 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
2109 tmp_dom.type = LTTNG_DOMAIN_UST;
2110
2111 switch (domain->type) {
2112 case LTTNG_DOMAIN_LOG4J:
2113 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
2114 break;
2115 case LTTNG_DOMAIN_JUL:
2116 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
2117 break;
2118 case LTTNG_DOMAIN_PYTHON:
2119 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
2120 break;
2121 default:
2122 /* The switch/case we are in makes this impossible */
2123 assert(0);
2124 }
2125
2126 {
2127 char *filter_expression_copy = NULL;
2128 struct lttng_filter_bytecode *filter_copy = NULL;
2129
2130 if (filter) {
2131 const size_t filter_size = sizeof(
2132 struct lttng_filter_bytecode)
2133 + filter->len;
2134
2135 filter_copy = zmalloc(filter_size);
2136 if (!filter_copy) {
2137 ret = LTTNG_ERR_NOMEM;
2138 goto error;
2139 }
2140 memcpy(filter_copy, filter, filter_size);
2141
2142 filter_expression_copy =
2143 strdup(filter_expression);
2144 if (!filter_expression) {
2145 ret = LTTNG_ERR_NOMEM;
2146 }
2147
2148 if (!filter_expression_copy || !filter_copy) {
2149 free(filter_expression_copy);
2150 free(filter_copy);
2151 goto error;
2152 }
2153 }
2154
2155 ret = cmd_enable_event_internal(session, &tmp_dom,
2156 (char *) default_chan_name,
2157 &uevent, filter_expression_copy,
2158 filter_copy, NULL, wpipe);
2159 }
2160
2161 if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
2162 goto already_enabled;
2163 } else if (ret != LTTNG_OK) {
2164 goto error;
2165 }
2166
2167 /* The wild card * means that everything should be enabled. */
2168 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
2169 ret = event_agent_enable_all(usess, agt, event, filter,
2170 filter_expression);
2171 } else {
2172 ret = event_agent_enable(usess, agt, event, filter,
2173 filter_expression);
2174 }
2175 filter = NULL;
2176 filter_expression = NULL;
2177 if (ret != LTTNG_OK) {
2178 goto error;
2179 }
2180
2181 break;
2182 }
2183 default:
2184 ret = LTTNG_ERR_UND;
2185 goto error;
2186 }
2187
2188 ret = LTTNG_OK;
2189
2190 already_enabled:
2191 error:
2192 free(filter_expression);
2193 free(filter);
2194 free(exclusion);
2195 free(attr);
2196 rcu_read_unlock();
2197 return ret;
2198 }
2199
2200 /*
2201 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2202 * We own filter, exclusion, and filter_expression.
2203 */
2204 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
2205 char *channel_name, struct lttng_event *event,
2206 char *filter_expression,
2207 struct lttng_filter_bytecode *filter,
2208 struct lttng_event_exclusion *exclusion,
2209 int wpipe)
2210 {
2211 return _cmd_enable_event(session, domain, channel_name, event,
2212 filter_expression, filter, exclusion, wpipe, false);
2213 }
2214
2215 /*
2216 * Enable an event which is internal to LTTng. An internal should
2217 * never be made visible to clients and are immune to checks such as
2218 * reserved names.
2219 */
2220 static int cmd_enable_event_internal(struct ltt_session *session,
2221 struct lttng_domain *domain,
2222 char *channel_name, struct lttng_event *event,
2223 char *filter_expression,
2224 struct lttng_filter_bytecode *filter,
2225 struct lttng_event_exclusion *exclusion,
2226 int wpipe)
2227 {
2228 return _cmd_enable_event(session, domain, channel_name, event,
2229 filter_expression, filter, exclusion, wpipe, true);
2230 }
2231
2232 /*
2233 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2234 */
2235 ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
2236 struct lttng_event **events)
2237 {
2238 int ret;
2239 ssize_t nb_events = 0;
2240
2241 switch (domain) {
2242 case LTTNG_DOMAIN_KERNEL:
2243 nb_events = kernel_list_events(kernel_tracer_fd, events);
2244 if (nb_events < 0) {
2245 ret = LTTNG_ERR_KERN_LIST_FAIL;
2246 goto error;
2247 }
2248 break;
2249 case LTTNG_DOMAIN_UST:
2250 nb_events = ust_app_list_events(events);
2251 if (nb_events < 0) {
2252 ret = LTTNG_ERR_UST_LIST_FAIL;
2253 goto error;
2254 }
2255 break;
2256 case LTTNG_DOMAIN_LOG4J:
2257 case LTTNG_DOMAIN_JUL:
2258 case LTTNG_DOMAIN_PYTHON:
2259 nb_events = agent_list_events(events, domain);
2260 if (nb_events < 0) {
2261 ret = LTTNG_ERR_UST_LIST_FAIL;
2262 goto error;
2263 }
2264 break;
2265 default:
2266 ret = LTTNG_ERR_UND;
2267 goto error;
2268 }
2269
2270 return nb_events;
2271
2272 error:
2273 /* Return negative value to differentiate return code */
2274 return -ret;
2275 }
2276
2277 /*
2278 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2279 */
2280 ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
2281 struct lttng_event_field **fields)
2282 {
2283 int ret;
2284 ssize_t nb_fields = 0;
2285
2286 switch (domain) {
2287 case LTTNG_DOMAIN_UST:
2288 nb_fields = ust_app_list_event_fields(fields);
2289 if (nb_fields < 0) {
2290 ret = LTTNG_ERR_UST_LIST_FAIL;
2291 goto error;
2292 }
2293 break;
2294 case LTTNG_DOMAIN_KERNEL:
2295 default: /* fall-through */
2296 ret = LTTNG_ERR_UND;
2297 goto error;
2298 }
2299
2300 return nb_fields;
2301
2302 error:
2303 /* Return negative value to differentiate return code */
2304 return -ret;
2305 }
2306
2307 ssize_t cmd_list_syscalls(struct lttng_event **events)
2308 {
2309 return syscall_table_list(events);
2310 }
2311
2312 /*
2313 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
2314 *
2315 * Called with session lock held.
2316 */
2317 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
2318 enum lttng_domain_type domain, int32_t **pids)
2319 {
2320 int ret;
2321 ssize_t nr_pids = 0;
2322
2323 switch (domain) {
2324 case LTTNG_DOMAIN_KERNEL:
2325 {
2326 struct ltt_kernel_session *ksess;
2327
2328 ksess = session->kernel_session;
2329 nr_pids = kernel_list_tracker_pids(ksess, pids);
2330 if (nr_pids < 0) {
2331 ret = LTTNG_ERR_KERN_LIST_FAIL;
2332 goto error;
2333 }
2334 break;
2335 }
2336 case LTTNG_DOMAIN_UST:
2337 {
2338 struct ltt_ust_session *usess;
2339
2340 usess = session->ust_session;
2341 nr_pids = trace_ust_list_tracker_pids(usess, pids);
2342 if (nr_pids < 0) {
2343 ret = LTTNG_ERR_UST_LIST_FAIL;
2344 goto error;
2345 }
2346 break;
2347 }
2348 case LTTNG_DOMAIN_LOG4J:
2349 case LTTNG_DOMAIN_JUL:
2350 case LTTNG_DOMAIN_PYTHON:
2351 default:
2352 ret = LTTNG_ERR_UND;
2353 goto error;
2354 }
2355
2356 return nr_pids;
2357
2358 error:
2359 /* Return negative value to differentiate return code */
2360 return -ret;
2361 }
2362
2363 /*
2364 * Command LTTNG_START_TRACE processed by the client thread.
2365 *
2366 * Called with session mutex held.
2367 */
2368 int cmd_start_trace(struct ltt_session *session)
2369 {
2370 int ret;
2371 unsigned long nb_chan = 0;
2372 struct ltt_kernel_session *ksession;
2373 struct ltt_ust_session *usess;
2374
2375 assert(session);
2376
2377 /* Ease our life a bit ;) */
2378 ksession = session->kernel_session;
2379 usess = session->ust_session;
2380
2381 /* Is the session already started? */
2382 if (session->active) {
2383 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2384 goto error;
2385 }
2386
2387 /*
2388 * Starting a session without channel is useless since after that it's not
2389 * possible to enable channel thus inform the client.
2390 */
2391 if (usess && usess->domain_global.channels) {
2392 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2393 }
2394 if (ksession) {
2395 nb_chan += ksession->channel_count;
2396 }
2397 if (!nb_chan) {
2398 ret = LTTNG_ERR_NO_CHANNEL;
2399 goto error;
2400 }
2401
2402 /* Kernel tracing */
2403 if (ksession != NULL) {
2404 ret = start_kernel_session(ksession, kernel_tracer_fd);
2405 if (ret != LTTNG_OK) {
2406 goto error;
2407 }
2408 }
2409
2410 /* Flag session that trace should start automatically */
2411 if (usess) {
2412 /*
2413 * Even though the start trace might fail, flag this session active so
2414 * other application coming in are started by default.
2415 */
2416 usess->active = 1;
2417
2418 ret = ust_app_start_trace_all(usess);
2419 if (ret < 0) {
2420 ret = LTTNG_ERR_UST_START_FAIL;
2421 goto error;
2422 }
2423 }
2424
2425 /* Flag this after a successful start. */
2426 session->has_been_started = 1;
2427 session->active = 1;
2428
2429 ret = LTTNG_OK;
2430
2431 error:
2432 return ret;
2433 }
2434
2435 /*
2436 * Command LTTNG_STOP_TRACE processed by the client thread.
2437 */
2438 int cmd_stop_trace(struct ltt_session *session)
2439 {
2440 int ret;
2441 struct ltt_kernel_channel *kchan;
2442 struct ltt_kernel_session *ksession;
2443 struct ltt_ust_session *usess;
2444
2445 assert(session);
2446
2447 /* Short cut */
2448 ksession = session->kernel_session;
2449 usess = session->ust_session;
2450
2451 /* Session is not active. Skip everythong and inform the client. */
2452 if (!session->active) {
2453 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2454 goto error;
2455 }
2456
2457 /* Kernel tracer */
2458 if (ksession && ksession->active) {
2459 DBG("Stop kernel tracing");
2460
2461 ret = kernel_stop_session(ksession);
2462 if (ret < 0) {
2463 ret = LTTNG_ERR_KERN_STOP_FAIL;
2464 goto error;
2465 }
2466
2467 kernel_wait_quiescent(kernel_tracer_fd);
2468
2469 /* Flush metadata after stopping (if exists) */
2470 if (ksession->metadata_stream_fd >= 0) {
2471 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2472 if (ret < 0) {
2473 ERR("Kernel metadata flush failed");
2474 }
2475 }
2476
2477 /* Flush all buffers after stopping */
2478 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2479 ret = kernel_flush_buffer(kchan);
2480 if (ret < 0) {
2481 ERR("Kernel flush buffer error");
2482 }
2483 }
2484
2485 ksession->active = 0;
2486 }
2487
2488 if (usess && usess->active) {
2489 /*
2490 * Even though the stop trace might fail, flag this session inactive so
2491 * other application coming in are not started by default.
2492 */
2493 usess->active = 0;
2494
2495 ret = ust_app_stop_trace_all(usess);
2496 if (ret < 0) {
2497 ret = LTTNG_ERR_UST_STOP_FAIL;
2498 goto error;
2499 }
2500 }
2501
2502 /* Flag inactive after a successful stop. */
2503 session->active = 0;
2504 ret = LTTNG_OK;
2505
2506 error:
2507 return ret;
2508 }
2509
2510 /*
2511 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2512 */
2513 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2514 struct lttng_uri *uris)
2515 {
2516 int ret, i;
2517 struct ltt_kernel_session *ksess = session->kernel_session;
2518 struct ltt_ust_session *usess = session->ust_session;
2519
2520 assert(session);
2521 assert(uris);
2522 assert(nb_uri > 0);
2523
2524 /* Can't set consumer URI if the session is active. */
2525 if (session->active) {
2526 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2527 goto error;
2528 }
2529
2530 /* Set the "global" consumer URIs */
2531 for (i = 0; i < nb_uri; i++) {
2532 ret = add_uri_to_consumer(session->consumer,
2533 &uris[i], 0, session->name);
2534 if (ret != LTTNG_OK) {
2535 goto error;
2536 }
2537 }
2538
2539 /* Set UST session URIs */
2540 if (session->ust_session) {
2541 for (i = 0; i < nb_uri; i++) {
2542 ret = add_uri_to_consumer(
2543 session->ust_session->consumer,
2544 &uris[i], LTTNG_DOMAIN_UST,
2545 session->name);
2546 if (ret != LTTNG_OK) {
2547 goto error;
2548 }
2549 }
2550 }
2551
2552 /* Set kernel session URIs */
2553 if (session->kernel_session) {
2554 for (i = 0; i < nb_uri; i++) {
2555 ret = add_uri_to_consumer(
2556 session->kernel_session->consumer,
2557 &uris[i], LTTNG_DOMAIN_KERNEL,
2558 session->name);
2559 if (ret != LTTNG_OK) {
2560 goto error;
2561 }
2562 }
2563 }
2564
2565 /*
2566 * Make sure to set the session in output mode after we set URI since a
2567 * session can be created without URL (thus flagged in no output mode).
2568 */
2569 session->output_traces = 1;
2570 if (ksess) {
2571 ksess->output_traces = 1;
2572 }
2573
2574 if (usess) {
2575 usess->output_traces = 1;
2576 }
2577
2578 /* All good! */
2579 ret = LTTNG_OK;
2580
2581 error:
2582 return ret;
2583 }
2584
2585 /*
2586 * Command LTTNG_CREATE_SESSION processed by the client thread.
2587 */
2588 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
2589 size_t nb_uri, lttng_sock_cred *creds, unsigned int live_timer)
2590 {
2591 int ret;
2592 struct ltt_session *session;
2593
2594 assert(name);
2595 assert(creds);
2596
2597 /*
2598 * Verify if the session already exist
2599 *
2600 * XXX: There is no need for the session lock list here since the caller
2601 * (process_client_msg) is holding it. We might want to change that so a
2602 * single command does not lock the entire session list.
2603 */
2604 session = session_find_by_name(name);
2605 if (session != NULL) {
2606 ret = LTTNG_ERR_EXIST_SESS;
2607 goto find_error;
2608 }
2609
2610 /* Create tracing session in the registry */
2611 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
2612 LTTNG_SOCK_GET_GID_CRED(creds));
2613 if (ret != LTTNG_OK) {
2614 goto session_error;
2615 }
2616
2617 /*
2618 * Get the newly created session pointer back
2619 *
2620 * XXX: There is no need for the session lock list here since the caller
2621 * (process_client_msg) is holding it. We might want to change that so a
2622 * single command does not lock the entire session list.
2623 */
2624 session = session_find_by_name(name);
2625 assert(session);
2626
2627 session->live_timer = live_timer;
2628 /* Create default consumer output for the session not yet created. */
2629 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
2630 if (session->consumer == NULL) {
2631 ret = LTTNG_ERR_FATAL;
2632 goto consumer_error;
2633 }
2634
2635 if (uris) {
2636 ret = cmd_set_consumer_uri(session, nb_uri, uris);
2637 if (ret != LTTNG_OK) {
2638 goto consumer_error;
2639 }
2640 session->output_traces = 1;
2641 } else {
2642 session->output_traces = 0;
2643 DBG2("Session %s created with no output", session->name);
2644 }
2645
2646 session->consumer->enabled = 1;
2647
2648 return LTTNG_OK;
2649
2650 consumer_error:
2651 session_destroy(session);
2652 session_error:
2653 find_error:
2654 return ret;
2655 }
2656
2657 /*
2658 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
2659 */
2660 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
2661 size_t nb_uri, lttng_sock_cred *creds)
2662 {
2663 int ret;
2664 struct ltt_session *session;
2665 struct snapshot_output *new_output = NULL;
2666
2667 assert(name);
2668 assert(creds);
2669
2670 /*
2671 * Create session in no output mode with URIs set to NULL. The uris we've
2672 * received are for a default snapshot output if one.
2673 */
2674 ret = cmd_create_session_uri(name, NULL, 0, creds, 0);
2675 if (ret != LTTNG_OK) {
2676 goto error;
2677 }
2678
2679 /* Get the newly created session pointer back. This should NEVER fail. */
2680 session = session_find_by_name(name);
2681 assert(session);
2682
2683 /* Flag session for snapshot mode. */
2684 session->snapshot_mode = 1;
2685
2686 /* Skip snapshot output creation if no URI is given. */
2687 if (nb_uri == 0) {
2688 goto end;
2689 }
2690
2691 new_output = snapshot_output_alloc();
2692 if (!new_output) {
2693 ret = LTTNG_ERR_NOMEM;
2694 goto error_snapshot_alloc;
2695 }
2696
2697 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
2698 uris, nb_uri, session->consumer, new_output, &session->snapshot);
2699 if (ret < 0) {
2700 if (ret == -ENOMEM) {
2701 ret = LTTNG_ERR_NOMEM;
2702 } else {
2703 ret = LTTNG_ERR_INVALID;
2704 }
2705 goto error_snapshot;
2706 }
2707
2708 rcu_read_lock();
2709 snapshot_add_output(&session->snapshot, new_output);
2710 rcu_read_unlock();
2711
2712 end:
2713 return LTTNG_OK;
2714
2715 error_snapshot:
2716 snapshot_output_destroy(new_output);
2717 error_snapshot_alloc:
2718 session_destroy(session);
2719 error:
2720 return ret;
2721 }
2722
2723 /*
2724 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2725 *
2726 * Called with session lock held.
2727 */
2728 int cmd_destroy_session(struct ltt_session *session, int wpipe)
2729 {
2730 int ret;
2731 struct ltt_ust_session *usess;
2732 struct ltt_kernel_session *ksess;
2733
2734 /* Safety net */
2735 assert(session);
2736
2737 usess = session->ust_session;
2738 ksess = session->kernel_session;
2739
2740 /* Clean kernel session teardown */
2741 kernel_destroy_session(ksess);
2742
2743 /* UST session teardown */
2744 if (usess) {
2745 /* Close any relayd session */
2746 consumer_output_send_destroy_relayd(usess->consumer);
2747
2748 /* Destroy every UST application related to this session. */
2749 ret = ust_app_destroy_trace_all(usess);
2750 if (ret) {
2751 ERR("Error in ust_app_destroy_trace_all");
2752 }
2753
2754 /* Clean up the rest. */
2755 trace_ust_destroy_session(usess);
2756 }
2757
2758 /*
2759 * Must notify the kernel thread here to update it's poll set in order to
2760 * remove the channel(s)' fd just destroyed.
2761 */
2762 ret = notify_thread_pipe(wpipe);
2763 if (ret < 0) {
2764 PERROR("write kernel poll pipe");
2765 }
2766
2767 ret = session_destroy(session);
2768
2769 return ret;
2770 }
2771
2772 /*
2773 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2774 */
2775 int cmd_register_consumer(struct ltt_session *session,
2776 enum lttng_domain_type domain, const char *sock_path,
2777 struct consumer_data *cdata)
2778 {
2779 int ret, sock;
2780 struct consumer_socket *socket = NULL;
2781
2782 assert(session);
2783 assert(cdata);
2784 assert(sock_path);
2785
2786 switch (domain) {
2787 case LTTNG_DOMAIN_KERNEL:
2788 {
2789 struct ltt_kernel_session *ksess = session->kernel_session;
2790
2791 assert(ksess);
2792
2793 /* Can't register a consumer if there is already one */
2794 if (ksess->consumer_fds_sent != 0) {
2795 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2796 goto error;
2797 }
2798
2799 sock = lttcomm_connect_unix_sock(sock_path);
2800 if (sock < 0) {
2801 ret = LTTNG_ERR_CONNECT_FAIL;
2802 goto error;
2803 }
2804 cdata->cmd_sock = sock;
2805
2806 socket = consumer_allocate_socket(&cdata->cmd_sock);
2807 if (socket == NULL) {
2808 ret = close(sock);
2809 if (ret < 0) {
2810 PERROR("close register consumer");
2811 }
2812 cdata->cmd_sock = -1;
2813 ret = LTTNG_ERR_FATAL;
2814 goto error;
2815 }
2816
2817 socket->lock = zmalloc(sizeof(pthread_mutex_t));
2818 if (socket->lock == NULL) {
2819 PERROR("zmalloc pthread mutex");
2820 ret = LTTNG_ERR_FATAL;
2821 goto error;
2822 }
2823 pthread_mutex_init(socket->lock, NULL);
2824 socket->registered = 1;
2825
2826 rcu_read_lock();
2827 consumer_add_socket(socket, ksess->consumer);
2828 rcu_read_unlock();
2829
2830 pthread_mutex_lock(&cdata->pid_mutex);
2831 cdata->pid = -1;
2832 pthread_mutex_unlock(&cdata->pid_mutex);
2833
2834 break;
2835 }
2836 default:
2837 /* TODO: Userspace tracing */
2838 ret = LTTNG_ERR_UND;
2839 goto error;
2840 }
2841
2842 return LTTNG_OK;
2843
2844 error:
2845 if (socket) {
2846 consumer_destroy_socket(socket);
2847 }
2848 return ret;
2849 }
2850
2851 /*
2852 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2853 */
2854 ssize_t cmd_list_domains(struct ltt_session *session,
2855 struct lttng_domain **domains)
2856 {
2857 int ret, index = 0;
2858 ssize_t nb_dom = 0;
2859 struct agent *agt;
2860 struct lttng_ht_iter iter;
2861
2862 if (session->kernel_session != NULL) {
2863 DBG3("Listing domains found kernel domain");
2864 nb_dom++;
2865 }
2866
2867 if (session->ust_session != NULL) {
2868 DBG3("Listing domains found UST global domain");
2869 nb_dom++;
2870
2871 rcu_read_lock();
2872 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2873 agt, node.node) {
2874 if (agt->being_used) {
2875 nb_dom++;
2876 }
2877 }
2878 rcu_read_unlock();
2879 }
2880
2881 if (!nb_dom) {
2882 goto end;
2883 }
2884
2885 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2886 if (*domains == NULL) {
2887 ret = LTTNG_ERR_FATAL;
2888 goto error;
2889 }
2890
2891 if (session->kernel_session != NULL) {
2892 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2893
2894 /* Kernel session buffer type is always GLOBAL */
2895 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
2896
2897 index++;
2898 }
2899
2900 if (session->ust_session != NULL) {
2901 (*domains)[index].type = LTTNG_DOMAIN_UST;
2902 (*domains)[index].buf_type = session->ust_session->buffer_type;
2903 index++;
2904
2905 rcu_read_lock();
2906 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2907 agt, node.node) {
2908 if (agt->being_used) {
2909 (*domains)[index].type = agt->domain;
2910 (*domains)[index].buf_type = session->ust_session->buffer_type;
2911 index++;
2912 }
2913 }
2914 rcu_read_unlock();
2915 }
2916 end:
2917 return nb_dom;
2918
2919 error:
2920 /* Return negative value to differentiate return code */
2921 return -ret;
2922 }
2923
2924
2925 /*
2926 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2927 */
2928 ssize_t cmd_list_channels(enum lttng_domain_type domain,
2929 struct ltt_session *session, struct lttng_channel **channels)
2930 {
2931 ssize_t nb_chan = 0, payload_size = 0, ret;
2932
2933 switch (domain) {
2934 case LTTNG_DOMAIN_KERNEL:
2935 if (session->kernel_session != NULL) {
2936 nb_chan = session->kernel_session->channel_count;
2937 }
2938 DBG3("Number of kernel channels %zd", nb_chan);
2939 if (nb_chan <= 0) {
2940 ret = -LTTNG_ERR_KERN_CHAN_NOT_FOUND;
2941 goto end;
2942 }
2943 break;
2944 case LTTNG_DOMAIN_UST:
2945 if (session->ust_session != NULL) {
2946 rcu_read_lock();
2947 nb_chan = lttng_ht_get_count(
2948 session->ust_session->domain_global.channels);
2949 rcu_read_unlock();
2950 }
2951 DBG3("Number of UST global channels %zd", nb_chan);
2952 if (nb_chan < 0) {
2953 ret = -LTTNG_ERR_UST_CHAN_NOT_FOUND;
2954 goto end;
2955 }
2956 break;
2957 default:
2958 ret = -LTTNG_ERR_UND;
2959 goto end;
2960 }
2961
2962 if (nb_chan > 0) {
2963 const size_t channel_size = sizeof(struct lttng_channel) +
2964 sizeof(struct lttcomm_channel_extended);
2965 struct lttcomm_channel_extended *channel_exts;
2966
2967 payload_size = nb_chan * channel_size;
2968 *channels = zmalloc(payload_size);
2969 if (*channels == NULL) {
2970 ret = -LTTNG_ERR_FATAL;
2971 goto end;
2972 }
2973
2974 channel_exts = ((void *) *channels) +
2975 (nb_chan * sizeof(struct lttng_channel));
2976 ret = list_lttng_channels(domain, session, *channels, channel_exts);
2977 if (ret != LTTNG_OK) {
2978 free(*channels);
2979 *channels = NULL;
2980 goto end;
2981 }
2982 } else {
2983 *channels = NULL;
2984 }
2985
2986 ret = payload_size;
2987 end:
2988 return ret;
2989 }
2990
2991 /*
2992 * Command LTTNG_LIST_EVENTS processed by the client thread.
2993 */
2994 ssize_t cmd_list_events(enum lttng_domain_type domain,
2995 struct ltt_session *session, char *channel_name,
2996 struct lttng_event **events, size_t *total_size)
2997 {
2998 int ret = 0;
2999 ssize_t nb_event = 0;
3000
3001 switch (domain) {
3002 case LTTNG_DOMAIN_KERNEL:
3003 if (session->kernel_session != NULL) {
3004 nb_event = list_lttng_kernel_events(channel_name,
3005 session->kernel_session, events,
3006 total_size);
3007 }
3008 break;
3009 case LTTNG_DOMAIN_UST:
3010 {
3011 if (session->ust_session != NULL) {
3012 nb_event = list_lttng_ust_global_events(channel_name,
3013 &session->ust_session->domain_global, events,
3014 total_size);
3015 }
3016 break;
3017 }
3018 case LTTNG_DOMAIN_LOG4J:
3019 case LTTNG_DOMAIN_JUL:
3020 case LTTNG_DOMAIN_PYTHON:
3021 if (session->ust_session) {
3022 struct lttng_ht_iter iter;
3023 struct agent *agt;
3024
3025 rcu_read_lock();
3026 cds_lfht_for_each_entry(session->ust_session->agents->ht,
3027 &iter.iter, agt, node.node) {
3028 if (agt->domain == domain) {
3029 nb_event = list_lttng_agent_events(
3030 agt, events,
3031 total_size);
3032 break;
3033 }
3034 }
3035 rcu_read_unlock();
3036 }
3037 break;
3038 default:
3039 ret = LTTNG_ERR_UND;
3040 goto error;
3041 }
3042
3043 return nb_event;
3044
3045 error:
3046 /* Return negative value to differentiate return code */
3047 return -ret;
3048 }
3049
3050 /*
3051 * Using the session list, filled a lttng_session array to send back to the
3052 * client for session listing.
3053 *
3054 * The session list lock MUST be acquired before calling this function. Use
3055 * session_lock_list() and session_unlock_list().
3056 */
3057 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
3058 gid_t gid)
3059 {
3060 int ret;
3061 unsigned int i = 0;
3062 struct ltt_session *session;
3063 struct ltt_session_list *list = session_get_list();
3064
3065 DBG("Getting all available session for UID %d GID %d",
3066 uid, gid);
3067 /*
3068 * Iterate over session list and append data after the control struct in
3069 * the buffer.
3070 */
3071 cds_list_for_each_entry(session, &list->head, list) {
3072 /*
3073 * Only list the sessions the user can control.
3074 */
3075 if (!session_access_ok(session, uid, gid)) {
3076 continue;
3077 }
3078
3079 struct ltt_kernel_session *ksess = session->kernel_session;
3080 struct ltt_ust_session *usess = session->ust_session;
3081
3082 if (session->consumer->type == CONSUMER_DST_NET ||
3083 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
3084 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
3085 ret = build_network_session_path(sessions[i].path,
3086 sizeof(sessions[i].path), session);
3087 } else {
3088 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
3089 session->consumer->dst.trace_path);
3090 }
3091 if (ret < 0) {
3092 PERROR("snprintf session path");
3093 continue;
3094 }
3095
3096 strncpy(sessions[i].name, session->name, NAME_MAX);
3097 sessions[i].name[NAME_MAX - 1] = '\0';
3098 sessions[i].enabled = session->active;
3099 sessions[i].snapshot_mode = session->snapshot_mode;
3100 sessions[i].live_timer_interval = session->live_timer;
3101 i++;
3102 }
3103 }
3104
3105 /*
3106 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
3107 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
3108 */
3109 int cmd_data_pending(struct ltt_session *session)
3110 {
3111 int ret;
3112 struct ltt_kernel_session *ksess = session->kernel_session;
3113 struct ltt_ust_session *usess = session->ust_session;
3114
3115 assert(session);
3116
3117 /* Session MUST be stopped to ask for data availability. */
3118 if (session->active) {
3119 ret = LTTNG_ERR_SESSION_STARTED;
3120 goto error;
3121 } else {
3122 /*
3123 * If stopped, just make sure we've started before else the above call
3124 * will always send that there is data pending.
3125 *
3126 * The consumer assumes that when the data pending command is received,
3127 * the trace has been started before or else no output data is written
3128 * by the streams which is a condition for data pending. So, this is
3129 * *VERY* important that we don't ask the consumer before a start
3130 * trace.
3131 */
3132 if (!session->has_been_started) {
3133 ret = 0;
3134 goto error;
3135 }
3136 }
3137
3138 if (ksess && ksess->consumer) {
3139 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
3140 if (ret == 1) {
3141 /* Data is still being extracted for the kernel. */
3142 goto error;
3143 }
3144 }
3145
3146 if (usess && usess->consumer) {
3147 ret = consumer_is_data_pending(usess->id, usess->consumer);
3148 if (ret == 1) {
3149 /* Data is still being extracted for the kernel. */
3150 goto error;
3151 }
3152 }
3153
3154 /* Data is ready to be read by a viewer */
3155 ret = 0;
3156
3157 error:
3158 return ret;
3159 }
3160
3161 /*
3162 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
3163 *
3164 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3165 */
3166 int cmd_snapshot_add_output(struct ltt_session *session,
3167 struct lttng_snapshot_output *output, uint32_t *id)
3168 {
3169 int ret;
3170 struct snapshot_output *new_output;
3171
3172 assert(session);
3173 assert(output);
3174
3175 DBG("Cmd snapshot add output for session %s", session->name);
3176
3177 /*
3178 * Can't create an output if the session is not set in no-output mode.
3179 */
3180 if (session->output_traces) {
3181 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3182 goto error;
3183 }
3184
3185 /* Only one output is allowed until we have the "tee" feature. */
3186 if (session->snapshot.nb_output == 1) {
3187 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
3188 goto error;
3189 }
3190
3191 new_output = snapshot_output_alloc();
3192 if (!new_output) {
3193 ret = LTTNG_ERR_NOMEM;
3194 goto error;
3195 }
3196
3197 ret = snapshot_output_init(output->max_size, output->name,
3198 output->ctrl_url, output->data_url, session->consumer, new_output,
3199 &session->snapshot);
3200 if (ret < 0) {
3201 if (ret == -ENOMEM) {
3202 ret = LTTNG_ERR_NOMEM;
3203 } else {
3204 ret = LTTNG_ERR_INVALID;
3205 }
3206 goto free_error;
3207 }
3208
3209 rcu_read_lock();
3210 snapshot_add_output(&session->snapshot, new_output);
3211 if (id) {
3212 *id = new_output->id;
3213 }
3214 rcu_read_unlock();
3215
3216 return LTTNG_OK;
3217
3218 free_error:
3219 snapshot_output_destroy(new_output);
3220 error:
3221 return ret;
3222 }
3223
3224 /*
3225 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
3226 *
3227 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3228 */
3229 int cmd_snapshot_del_output(struct ltt_session *session,
3230 struct lttng_snapshot_output *output)
3231 {
3232 int ret;
3233 struct snapshot_output *sout = NULL;
3234
3235 assert(session);
3236 assert(output);
3237
3238 rcu_read_lock();
3239
3240 /*
3241 * Permission denied to create an output if the session is not
3242 * set in no output mode.
3243 */
3244 if (session->output_traces) {
3245 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3246 goto error;
3247 }
3248
3249 if (output->id) {
3250 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
3251 session->name);
3252 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
3253 } else if (*output->name != '\0') {
3254 DBG("Cmd snapshot del output name %s for session %s", output->name,
3255 session->name);
3256 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
3257 }
3258 if (!sout) {
3259 ret = LTTNG_ERR_INVALID;
3260 goto error;
3261 }
3262
3263 snapshot_delete_output(&session->snapshot, sout);
3264 snapshot_output_destroy(sout);
3265 ret = LTTNG_OK;
3266
3267 error:
3268 rcu_read_unlock();
3269 return ret;
3270 }
3271
3272 /*
3273 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
3274 *
3275 * If no output is available, outputs is untouched and 0 is returned.
3276 *
3277 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
3278 */
3279 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
3280 struct lttng_snapshot_output **outputs)
3281 {
3282 int ret, idx = 0;
3283 struct lttng_snapshot_output *list = NULL;
3284 struct lttng_ht_iter iter;
3285 struct snapshot_output *output;
3286
3287 assert(session);
3288 assert(outputs);
3289
3290 DBG("Cmd snapshot list outputs for session %s", session->name);
3291
3292 /*
3293 * Permission denied to create an output if the session is not
3294 * set in no output mode.
3295 */
3296 if (session->output_traces) {
3297 ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3298 goto end;
3299 }
3300
3301 if (session->snapshot.nb_output == 0) {
3302 ret = 0;
3303 goto end;
3304 }
3305
3306 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
3307 if (!list) {
3308 ret = -LTTNG_ERR_NOMEM;
3309 goto end;
3310 }
3311
3312 /* Copy list from session to the new list object. */
3313 rcu_read_lock();
3314 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
3315 output, node.node) {
3316 assert(output->consumer);
3317 list[idx].id = output->id;
3318 list[idx].max_size = output->max_size;
3319 if (lttng_strncpy(list[idx].name, output->name,
3320 sizeof(list[idx].name))) {
3321 ret = -LTTNG_ERR_INVALID;
3322 goto error;
3323 }
3324 if (output->consumer->type == CONSUMER_DST_LOCAL) {
3325 if (lttng_strncpy(list[idx].ctrl_url,
3326 output->consumer->dst.trace_path,
3327 sizeof(list[idx].ctrl_url))) {
3328 ret = -LTTNG_ERR_INVALID;
3329 goto error;
3330 }
3331 } else {
3332 /* Control URI. */
3333 ret = uri_to_str_url(&output->consumer->dst.net.control,
3334 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
3335 if (ret < 0) {
3336 ret = -LTTNG_ERR_NOMEM;
3337 goto error;
3338 }
3339
3340 /* Data URI. */
3341 ret = uri_to_str_url(&output->consumer->dst.net.data,
3342 list[idx].data_url, sizeof(list[idx].data_url));
3343 if (ret < 0) {
3344 ret = -LTTNG_ERR_NOMEM;
3345 goto error;
3346 }
3347 }
3348 idx++;
3349 }
3350
3351 *outputs = list;
3352 list = NULL;
3353 ret = session->snapshot.nb_output;
3354 error:
3355 rcu_read_unlock();
3356 free(list);
3357 end:
3358 return ret;
3359 }
3360
3361 /*
3362 * Check if we can regenerate the metadata for this session.
3363 * Only kernel, UST per-uid and non-live sessions are supported.
3364 *
3365 * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
3366 */
3367 static
3368 int check_regenerate_metadata_support(struct ltt_session *session)
3369 {
3370 int ret;
3371
3372 assert(session);
3373
3374 if (session->live_timer != 0) {
3375 ret = LTTNG_ERR_LIVE_SESSION;
3376 goto end;
3377 }
3378 if (!session->active) {
3379 ret = LTTNG_ERR_SESSION_NOT_STARTED;
3380 goto end;
3381 }
3382 if (session->ust_session) {
3383 switch (session->ust_session->buffer_type) {
3384 case LTTNG_BUFFER_PER_UID:
3385 break;
3386 case LTTNG_BUFFER_PER_PID:
3387 ret = LTTNG_ERR_PER_PID_SESSION;
3388 goto end;
3389 default:
3390 assert(0);
3391 ret = LTTNG_ERR_UNK;
3392 goto end;
3393 }
3394 }
3395 if (session->consumer->type == CONSUMER_DST_NET &&
3396 session->consumer->relay_minor_version < 8) {
3397 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
3398 goto end;
3399 }
3400 ret = 0;
3401
3402 end:
3403 return ret;
3404 }
3405
3406 static
3407 int clear_metadata_file(int fd)
3408 {
3409 int ret;
3410 off_t lseek_ret;
3411
3412 lseek_ret = lseek(fd, 0, SEEK_SET);
3413 if (lseek_ret < 0) {
3414 PERROR("lseek");
3415 ret = -1;
3416 goto end;
3417 }
3418
3419 ret = ftruncate(fd, 0);
3420 if (ret < 0) {
3421 PERROR("ftruncate");
3422 goto end;
3423 }
3424
3425 end:
3426 return ret;
3427 }
3428
3429 static
3430 int ust_regenerate_metadata(struct ltt_ust_session *usess)
3431 {
3432 int ret = 0;
3433 struct buffer_reg_uid *uid_reg = NULL;
3434 struct buffer_reg_session *session_reg = NULL;
3435
3436 rcu_read_lock();
3437 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
3438 struct ust_registry_session *registry;
3439 struct ust_registry_channel *chan;
3440 struct lttng_ht_iter iter_chan;
3441
3442 session_reg = uid_reg->registry;
3443 registry = session_reg->reg.ust;
3444
3445 pthread_mutex_lock(&registry->lock);
3446 registry->metadata_len_sent = 0;
3447 memset(registry->metadata, 0, registry->metadata_alloc_len);
3448 registry->metadata_len = 0;
3449 registry->metadata_version++;
3450 if (registry->metadata_fd > 0) {
3451 /* Clear the metadata file's content. */
3452 ret = clear_metadata_file(registry->metadata_fd);
3453 if (ret) {
3454 pthread_mutex_unlock(&registry->lock);
3455 goto end;
3456 }
3457 }
3458
3459 ret = ust_metadata_session_statedump(registry, NULL,
3460 registry->major, registry->minor);
3461 if (ret) {
3462 pthread_mutex_unlock(&registry->lock);
3463 ERR("Failed to generate session metadata (err = %d)",
3464 ret);
3465 goto end;
3466 }
3467 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
3468 chan, node.node) {
3469 struct ust_registry_event *event;
3470 struct lttng_ht_iter iter_event;
3471
3472 ret = ust_metadata_channel_statedump(registry, chan);
3473 if (ret) {
3474 pthread_mutex_unlock(&registry->lock);
3475 ERR("Failed to generate channel metadata "
3476 "(err = %d)", ret);
3477 goto end;
3478 }
3479 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
3480 event, node.node) {
3481 ret = ust_metadata_event_statedump(registry,
3482 chan, event);
3483 if (ret) {
3484 pthread_mutex_unlock(&registry->lock);
3485 ERR("Failed to generate event metadata "
3486 "(err = %d)", ret);
3487 goto end;
3488 }
3489 }
3490 }
3491 pthread_mutex_unlock(&registry->lock);
3492 }
3493
3494 end:
3495 rcu_read_unlock();
3496 return ret;
3497 }
3498
3499 /*
3500 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
3501 *
3502 * Ask the consumer to truncate the existing metadata file(s) and
3503 * then regenerate the metadata. Live and per-pid sessions are not
3504 * supported and return an error.
3505 *
3506 * Return 0 on success or else a LTTNG_ERR code.
3507 */
3508 int cmd_regenerate_metadata(struct ltt_session *session)
3509 {
3510 int ret;
3511
3512 assert(session);
3513
3514 ret = check_regenerate_metadata_support(session);
3515 if (ret) {
3516 goto end;
3517 }
3518
3519 if (session->kernel_session) {
3520 ret = kernctl_session_regenerate_metadata(
3521 session->kernel_session->fd);
3522 if (ret < 0) {
3523 ERR("Failed to regenerate the kernel metadata");
3524 goto end;
3525 }
3526 }
3527
3528 if (session->ust_session) {
3529 ret = ust_regenerate_metadata(session->ust_session);
3530 if (ret < 0) {
3531 ERR("Failed to regenerate the UST metadata");
3532 goto end;
3533 }
3534 }
3535 DBG("Cmd metadata regenerate for session %s", session->name);
3536 ret = LTTNG_OK;
3537
3538 end:
3539 return ret;
3540 }
3541
3542 /*
3543 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
3544 *
3545 * Ask the tracer to regenerate a new statedump.
3546 *
3547 * Return 0 on success or else a LTTNG_ERR code.
3548 */
3549 int cmd_regenerate_statedump(struct ltt_session *session)
3550 {
3551 int ret;
3552
3553 assert(session);
3554
3555 if (!session->active) {
3556 ret = LTTNG_ERR_SESSION_NOT_STARTED;
3557 goto end;
3558 }
3559 ret = 0;
3560
3561 if (session->kernel_session) {
3562 ret = kernctl_session_regenerate_statedump(
3563 session->kernel_session->fd);
3564 /*
3565 * Currently, the statedump in kernel can only fail if out
3566 * of memory.
3567 */
3568 if (ret < 0) {
3569 if (ret == -ENOMEM) {
3570 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
3571 } else {
3572 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
3573 }
3574 ERR("Failed to regenerate the kernel statedump");
3575 goto end;
3576 }
3577 }
3578
3579 if (session->ust_session) {
3580 ret = ust_app_regenerate_statedump_all(session->ust_session);
3581 /*
3582 * Currently, the statedump in UST always returns 0.
3583 */
3584 if (ret < 0) {
3585 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
3586 ERR("Failed to regenerate the UST statedump");
3587 goto end;
3588 }
3589 }
3590 DBG("Cmd regenerate statedump for session %s", session->name);
3591 ret = LTTNG_OK;
3592
3593 end:
3594 return ret;
3595 }
3596
3597 /*
3598 * Send relayd sockets from snapshot output to consumer. Ignore request if the
3599 * snapshot output is *not* set with a remote destination.
3600 *
3601 * Return 0 on success or a LTTNG_ERR code.
3602 */
3603 static int set_relayd_for_snapshot(struct consumer_output *consumer,
3604 struct snapshot_output *snap_output, struct ltt_session *session)
3605 {
3606 int ret = LTTNG_OK;
3607 struct lttng_ht_iter iter;
3608 struct consumer_socket *socket;
3609
3610 assert(consumer);
3611 assert(snap_output);
3612 assert(session);
3613
3614 DBG2("Set relayd object from snapshot output");
3615
3616 /* Ignore if snapshot consumer output is not network. */
3617 if (snap_output->consumer->type != CONSUMER_DST_NET) {
3618 goto error;
3619 }
3620
3621 /*
3622 * For each consumer socket, create and send the relayd object of the
3623 * snapshot output.
3624 */
3625 rcu_read_lock();
3626 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
3627 socket, node.node) {
3628 pthread_mutex_lock(socket->lock);
3629 ret = send_consumer_relayd_sockets(0, session->id,
3630 snap_output->consumer, socket,
3631 session->name, session->hostname,
3632 session->live_timer);
3633 pthread_mutex_unlock(socket->lock);
3634 if (ret != LTTNG_OK) {
3635 rcu_read_unlock();
3636 goto error;
3637 }
3638 }
3639 rcu_read_unlock();
3640
3641 error:
3642 return ret;
3643 }
3644
3645 /*
3646 * Record a kernel snapshot.
3647 *
3648 * Return LTTNG_OK on success or a LTTNG_ERR code.
3649 */
3650 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
3651 struct snapshot_output *output, struct ltt_session *session,
3652 int wait, uint64_t nb_packets_per_stream)
3653 {
3654 int ret;
3655
3656 assert(ksess);
3657 assert(output);
3658 assert(session);
3659
3660
3661 /*
3662 * Copy kernel session sockets so we can communicate with the right
3663 * consumer for the snapshot record command.
3664 */
3665 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
3666 if (ret < 0) {
3667 ret = LTTNG_ERR_NOMEM;
3668 goto error;
3669 }
3670
3671 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
3672 if (ret != LTTNG_OK) {
3673 goto error_snapshot;
3674 }
3675
3676 ret = kernel_snapshot_record(ksess, output, wait, nb_packets_per_stream);
3677 if (ret != LTTNG_OK) {
3678 goto error_snapshot;
3679 }
3680
3681 ret = LTTNG_OK;
3682 goto end;
3683
3684 error_snapshot:
3685 /* Clean up copied sockets so this output can use some other later on. */
3686 consumer_destroy_output_sockets(output->consumer);
3687 error:
3688 end:
3689 return ret;
3690 }
3691
3692 /*
3693 * Record a UST snapshot.
3694 *
3695 * Return 0 on success or a LTTNG_ERR error code.
3696 */
3697 static int record_ust_snapshot(struct ltt_ust_session *usess,
3698 struct snapshot_output *output, struct ltt_session *session,
3699 int wait, uint64_t nb_packets_per_stream)
3700 {
3701 int ret;
3702
3703 assert(usess);
3704 assert(output);
3705 assert(session);
3706
3707 /*
3708 * Copy UST session sockets so we can communicate with the right
3709 * consumer for the snapshot record command.
3710 */
3711 ret = consumer_copy_sockets(output->consumer, usess->consumer);
3712 if (ret < 0) {
3713 ret = LTTNG_ERR_NOMEM;
3714 goto error;
3715 }
3716
3717 ret = set_relayd_for_snapshot(usess->consumer, output, session);
3718 if (ret != LTTNG_OK) {
3719 goto error_snapshot;
3720 }
3721
3722 ret = ust_app_snapshot_record(usess, output, wait, nb_packets_per_stream);
3723 if (ret < 0) {
3724 switch (-ret) {
3725 case EINVAL:
3726 ret = LTTNG_ERR_INVALID;
3727 break;
3728 default:
3729 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3730 break;
3731 }
3732 goto error_snapshot;
3733 }
3734
3735 ret = LTTNG_OK;
3736
3737 error_snapshot:
3738 /* Clean up copied sockets so this output can use some other later on. */
3739 consumer_destroy_output_sockets(output->consumer);
3740 error:
3741 return ret;
3742 }
3743
3744 static
3745 uint64_t get_session_size_one_more_packet_per_stream(struct ltt_session *session,
3746 uint64_t cur_nr_packets)
3747 {
3748 uint64_t tot_size = 0;
3749
3750 if (session->kernel_session) {
3751 struct ltt_kernel_channel *chan;
3752 struct ltt_kernel_session *ksess = session->kernel_session;
3753
3754 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
3755 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
3756 /*
3757 * Don't take channel into account if we
3758 * already grab all its packets.
3759 */
3760 continue;
3761 }
3762 tot_size += chan->channel->attr.subbuf_size
3763 * chan->stream_count;
3764 }
3765 }
3766
3767 if (session->ust_session) {
3768 struct ltt_ust_session *usess = session->ust_session;
3769
3770 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
3771 cur_nr_packets);
3772 }
3773
3774 return tot_size;
3775 }
3776
3777 /*
3778 * Calculate the number of packets we can grab from each stream that
3779 * fits within the overall snapshot max size.
3780 *
3781 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
3782 * the number of packets per stream.
3783 *
3784 * TODO: this approach is not perfect: we consider the worse case
3785 * (packet filling the sub-buffers) as an upper bound, but we could do
3786 * better if we do this calculation while we actually grab the packet
3787 * content: we would know how much padding we don't actually store into
3788 * the file.
3789 *
3790 * This algorithm is currently bounded by the number of packets per
3791 * stream.
3792 *
3793 * Since we call this algorithm before actually grabbing the data, it's
3794 * an approximation: for instance, applications could appear/disappear
3795 * in between this call and actually grabbing data.
3796 */
3797 static
3798 int64_t get_session_nb_packets_per_stream(struct ltt_session *session, uint64_t max_size)
3799 {
3800 int64_t size_left;
3801 uint64_t cur_nb_packets = 0;
3802
3803 if (!max_size) {
3804 return 0; /* Infinite */
3805 }
3806
3807 size_left = max_size;
3808 for (;;) {
3809 uint64_t one_more_packet_tot_size;
3810
3811 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(session,
3812 cur_nb_packets);
3813 if (!one_more_packet_tot_size) {
3814 /* We are already grabbing all packets. */
3815 break;
3816 }
3817 size_left -= one_more_packet_tot_size;
3818 if (size_left < 0) {
3819 break;
3820 }
3821 cur_nb_packets++;
3822 }
3823 if (!cur_nb_packets) {
3824 /* Not enough room to grab one packet of each stream, error. */
3825 return -1;
3826 }
3827 return cur_nb_packets;
3828 }
3829
3830 /*
3831 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
3832 *
3833 * The wait parameter is ignored so this call always wait for the snapshot to
3834 * complete before returning.
3835 *
3836 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3837 */
3838 int cmd_snapshot_record(struct ltt_session *session,
3839 struct lttng_snapshot_output *output, int wait)
3840 {
3841 int ret = LTTNG_OK;
3842 unsigned int use_tmp_output = 0;
3843 struct snapshot_output tmp_output;
3844 unsigned int snapshot_success = 0;
3845 char datetime[16];
3846
3847 assert(session);
3848 assert(output);
3849
3850 DBG("Cmd snapshot record for session %s", session->name);
3851
3852 /* Get the datetime for the snapshot output directory. */
3853 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
3854 sizeof(datetime));
3855 if (!ret) {
3856 ret = LTTNG_ERR_INVALID;
3857 goto error;
3858 }
3859
3860 /*
3861 * Permission denied to create an output if the session is not
3862 * set in no output mode.
3863 */
3864 if (session->output_traces) {
3865 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3866 goto error;
3867 }
3868
3869 /* The session needs to be started at least once. */
3870 if (!session->has_been_started) {
3871 ret = LTTNG_ERR_START_SESSION_ONCE;
3872 goto error;
3873 }
3874
3875 /* Use temporary output for the session. */
3876 if (*output->ctrl_url != '\0') {
3877 ret = snapshot_output_init(output->max_size, output->name,
3878 output->ctrl_url, output->data_url, session->consumer,
3879 &tmp_output, NULL);
3880 if (ret < 0) {
3881 if (ret == -ENOMEM) {
3882 ret = LTTNG_ERR_NOMEM;
3883 } else {
3884 ret = LTTNG_ERR_INVALID;
3885 }
3886 goto error;
3887 }
3888 /* Use the global session count for the temporary snapshot. */
3889 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3890
3891 /* Use the global datetime */
3892 memcpy(tmp_output.datetime, datetime, sizeof(datetime));
3893 use_tmp_output = 1;
3894 }
3895
3896 if (use_tmp_output) {
3897 int64_t nb_packets_per_stream;
3898
3899 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3900 tmp_output.max_size);
3901 if (nb_packets_per_stream < 0) {
3902 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3903 goto error;
3904 }
3905
3906 if (session->kernel_session) {
3907 ret = record_kernel_snapshot(session->kernel_session,
3908 &tmp_output, session,
3909 wait, nb_packets_per_stream);
3910 if (ret != LTTNG_OK) {
3911 goto error;
3912 }
3913 }
3914
3915 if (session->ust_session) {
3916 ret = record_ust_snapshot(session->ust_session,
3917 &tmp_output, session,
3918 wait, nb_packets_per_stream);
3919 if (ret != LTTNG_OK) {
3920 goto error;
3921 }
3922 }
3923
3924 snapshot_success = 1;
3925 } else {
3926 struct snapshot_output *sout;
3927 struct lttng_ht_iter iter;
3928
3929 rcu_read_lock();
3930 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3931 &iter.iter, sout, node.node) {
3932 int64_t nb_packets_per_stream;
3933
3934 /*
3935 * Make a local copy of the output and assign the possible
3936 * temporary value given by the caller.
3937 */
3938 memset(&tmp_output, 0, sizeof(tmp_output));
3939 memcpy(&tmp_output, sout, sizeof(tmp_output));
3940
3941 if (output->max_size != (uint64_t) -1ULL) {
3942 tmp_output.max_size = output->max_size;
3943 }
3944
3945 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3946 tmp_output.max_size);
3947 if (nb_packets_per_stream < 0) {
3948 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3949 rcu_read_unlock();
3950 goto error;
3951 }
3952
3953 /* Use temporary name. */
3954 if (*output->name != '\0') {
3955 if (lttng_strncpy(tmp_output.name, output->name,
3956 sizeof(tmp_output.name))) {
3957 ret = LTTNG_ERR_INVALID;
3958 rcu_read_unlock();
3959 goto error;
3960 }
3961 }
3962
3963 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3964 memcpy(tmp_output.datetime, datetime, sizeof(datetime));
3965
3966 if (session->kernel_session) {
3967 ret = record_kernel_snapshot(session->kernel_session,
3968 &tmp_output, session,
3969 wait, nb_packets_per_stream);
3970 if (ret != LTTNG_OK) {
3971 rcu_read_unlock();
3972 goto error;
3973 }
3974 }
3975
3976 if (session->ust_session) {
3977 ret = record_ust_snapshot(session->ust_session,
3978 &tmp_output, session,
3979 wait, nb_packets_per_stream);
3980 if (ret != LTTNG_OK) {
3981 rcu_read_unlock();
3982 goto error;
3983 }
3984 }
3985 snapshot_success = 1;
3986 }
3987 rcu_read_unlock();
3988 }
3989
3990 if (snapshot_success) {
3991 session->snapshot.nb_snapshot++;
3992 } else {
3993 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3994 }
3995
3996 error:
3997 return ret;
3998 }
3999
4000 /*
4001 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
4002 */
4003 int cmd_set_session_shm_path(struct ltt_session *session,
4004 const char *shm_path)
4005 {
4006 /* Safety net */
4007 assert(session);
4008
4009 /*
4010 * Can only set shm path before session is started.
4011 */
4012 if (session->has_been_started) {
4013 return LTTNG_ERR_SESSION_STARTED;
4014 }
4015
4016 strncpy(session->shm_path, shm_path,
4017 sizeof(session->shm_path));
4018 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
4019
4020 return 0;
4021 }
4022
4023 /*
4024 * Init command subsystem.
4025 */
4026 void cmd_init(void)
4027 {
4028 /*
4029 * Set network sequence index to 1 for streams to match a relayd
4030 * socket on the consumer side.
4031 */
4032 pthread_mutex_lock(&relayd_net_seq_idx_lock);
4033 relayd_net_seq_idx = 1;
4034 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
4035
4036 DBG("Command subsystem initialized");
4037 }
LTTng tools - Deliverables
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