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67b2e77f49c34ff690bf9467ad975c95c85ef59c
[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 #include <common/dynamic-buffer.h>
33 #include <common/buffer-view.h>
34 #include <lttng/trigger/trigger-internal.h>
35 #include <lttng/condition/condition.h>
36 #include <lttng/action/action.h>
37 #include <lttng/channel.h>
38 #include <lttng/channel-internal.h>
39 #include <common/string-utils/string-utils.h>
40
41 #include "channel.h"
42 #include "consumer.h"
43 #include "event.h"
44 #include "health-sessiond.h"
45 #include "kernel.h"
46 #include "kernel-consumer.h"
47 #include "lttng-sessiond.h"
48 #include "utils.h"
49 #include "syscall.h"
50 #include "agent.h"
51 #include "buffer-registry.h"
52 #include "notification-thread.h"
53 #include "notification-thread-commands.h"
54
55 #include "cmd.h"
56
57 /*
58 * Used to keep a unique index for each relayd socket created where this value
59 * is associated with streams on the consumer so it can match the right relayd
60 * to send to. It must be accessed with the relayd_net_seq_idx_lock
61 * held.
62 */
63 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
64 static uint64_t relayd_net_seq_idx;
65
66 static int validate_ust_event_name(const char *);
67 static int cmd_enable_event_internal(struct ltt_session *session,
68 struct lttng_domain *domain,
69 char *channel_name, struct lttng_event *event,
70 char *filter_expression,
71 struct lttng_filter_bytecode *filter,
72 struct lttng_event_exclusion *exclusion,
73 int wpipe);
74
75 /*
76 * Create a session path used by list_lttng_sessions for the case that the
77 * session consumer is on the network.
78 */
79 static int build_network_session_path(char *dst, size_t size,
80 struct ltt_session *session)
81 {
82 int ret, kdata_port, udata_port;
83 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
84 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
85
86 assert(session);
87 assert(dst);
88
89 memset(tmp_urls, 0, sizeof(tmp_urls));
90 memset(tmp_uurl, 0, sizeof(tmp_uurl));
91
92 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
93
94 if (session->kernel_session && session->kernel_session->consumer) {
95 kuri = &session->kernel_session->consumer->dst.net.control;
96 kdata_port = session->kernel_session->consumer->dst.net.data.port;
97 }
98
99 if (session->ust_session && session->ust_session->consumer) {
100 uuri = &session->ust_session->consumer->dst.net.control;
101 udata_port = session->ust_session->consumer->dst.net.data.port;
102 }
103
104 if (uuri == NULL && kuri == NULL) {
105 uri = &session->consumer->dst.net.control;
106 kdata_port = session->consumer->dst.net.data.port;
107 } else if (kuri && uuri) {
108 ret = uri_compare(kuri, uuri);
109 if (ret) {
110 /* Not Equal */
111 uri = kuri;
112 /* Build uuri URL string */
113 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
114 if (ret < 0) {
115 goto error;
116 }
117 } else {
118 uri = kuri;
119 }
120 } else if (kuri && uuri == NULL) {
121 uri = kuri;
122 } else if (uuri && kuri == NULL) {
123 uri = uuri;
124 }
125
126 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
127 if (ret < 0) {
128 goto error;
129 }
130
131 /*
132 * Do we have a UST url set. If yes, this means we have both kernel and UST
133 * to print.
134 */
135 if (*tmp_uurl != '\0') {
136 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
137 tmp_urls, kdata_port, tmp_uurl, udata_port);
138 } else {
139 int dport;
140 if (kuri || (!kuri && !uuri)) {
141 dport = kdata_port;
142 } else {
143 /* No kernel URI, use the UST port. */
144 dport = udata_port;
145 }
146 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
147 }
148
149 error:
150 return ret;
151 }
152
153 /*
154 * Get run-time attributes if the session has been started (discarded events,
155 * lost packets).
156 */
157 static int get_kernel_runtime_stats(struct ltt_session *session,
158 struct ltt_kernel_channel *kchan, uint64_t *discarded_events,
159 uint64_t *lost_packets)
160 {
161 int ret;
162
163 if (!session->has_been_started) {
164 ret = 0;
165 *discarded_events = 0;
166 *lost_packets = 0;
167 goto end;
168 }
169
170 ret = consumer_get_discarded_events(session->id, kchan->fd,
171 session->kernel_session->consumer,
172 discarded_events);
173 if (ret < 0) {
174 goto end;
175 }
176
177 ret = consumer_get_lost_packets(session->id, kchan->fd,
178 session->kernel_session->consumer,
179 lost_packets);
180 if (ret < 0) {
181 goto end;
182 }
183
184 end:
185 return ret;
186 }
187
188 /*
189 * Get run-time attributes if the session has been started (discarded events,
190 * lost packets).
191 */
192 static int get_ust_runtime_stats(struct ltt_session *session,
193 struct ltt_ust_channel *uchan, uint64_t *discarded_events,
194 uint64_t *lost_packets)
195 {
196 int ret;
197 struct ltt_ust_session *usess;
198
199 if (!discarded_events || !lost_packets) {
200 ret = -1;
201 goto end;
202 }
203
204 usess = session->ust_session;
205 assert(discarded_events);
206 assert(lost_packets);
207
208 if (!usess || !session->has_been_started) {
209 *discarded_events = 0;
210 *lost_packets = 0;
211 ret = 0;
212 goto end;
213 }
214
215 if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
216 ret = ust_app_uid_get_channel_runtime_stats(usess->id,
217 &usess->buffer_reg_uid_list,
218 usess->consumer, uchan->id,
219 uchan->attr.overwrite,
220 discarded_events,
221 lost_packets);
222 } else if (usess->buffer_type == LTTNG_BUFFER_PER_PID) {
223 ret = ust_app_pid_get_channel_runtime_stats(usess,
224 uchan, usess->consumer,
225 uchan->attr.overwrite,
226 discarded_events,
227 lost_packets);
228 if (ret < 0) {
229 goto end;
230 }
231 *discarded_events += uchan->per_pid_closed_app_discarded;
232 *lost_packets += uchan->per_pid_closed_app_lost;
233 } else {
234 ERR("Unsupported buffer type");
235 assert(0);
236 ret = -1;
237 goto end;
238 }
239
240 end:
241 return ret;
242 }
243
244 /*
245 * Fill lttng_channel array of all channels.
246 */
247 static ssize_t list_lttng_channels(enum lttng_domain_type domain,
248 struct ltt_session *session, struct lttng_channel *channels,
249 struct lttng_channel_extended *chan_exts)
250 {
251 int i = 0, ret = 0;
252 struct ltt_kernel_channel *kchan;
253
254 DBG("Listing channels for session %s", session->name);
255
256 switch (domain) {
257 case LTTNG_DOMAIN_KERNEL:
258 /* Kernel channels */
259 if (session->kernel_session != NULL) {
260 cds_list_for_each_entry(kchan,
261 &session->kernel_session->channel_list.head, list) {
262 uint64_t discarded_events, lost_packets;
263 struct lttng_channel_extended *extended;
264
265 extended = (struct lttng_channel_extended *)
266 kchan->channel->attr.extended.ptr;
267
268 ret = get_kernel_runtime_stats(session, kchan,
269 &discarded_events, &lost_packets);
270 if (ret < 0) {
271 goto end;
272 }
273 /* Copy lttng_channel struct to array */
274 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
275 channels[i].enabled = kchan->enabled;
276 chan_exts[i].discarded_events =
277 discarded_events;
278 chan_exts[i].lost_packets = lost_packets;
279 chan_exts[i].monitor_timer_interval =
280 extended->monitor_timer_interval;
281 chan_exts[i].blocking_timeout = 0;
282 i++;
283 }
284 }
285 break;
286 case LTTNG_DOMAIN_UST:
287 {
288 struct lttng_ht_iter iter;
289 struct ltt_ust_channel *uchan;
290
291 rcu_read_lock();
292 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
293 &iter.iter, uchan, node.node) {
294 uint64_t discarded_events = 0, lost_packets = 0;
295
296 if (lttng_strncpy(channels[i].name, uchan->name,
297 LTTNG_SYMBOL_NAME_LEN)) {
298 break;
299 }
300 channels[i].attr.overwrite = uchan->attr.overwrite;
301 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
302 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
303 channels[i].attr.switch_timer_interval =
304 uchan->attr.switch_timer_interval;
305 channels[i].attr.read_timer_interval =
306 uchan->attr.read_timer_interval;
307 channels[i].enabled = uchan->enabled;
308 channels[i].attr.tracefile_size = uchan->tracefile_size;
309 channels[i].attr.tracefile_count = uchan->tracefile_count;
310
311 /*
312 * Map enum lttng_ust_output to enum lttng_event_output.
313 */
314 switch (uchan->attr.output) {
315 case LTTNG_UST_MMAP:
316 channels[i].attr.output = LTTNG_EVENT_MMAP;
317 break;
318 default:
319 /*
320 * LTTNG_UST_MMAP is the only supported UST
321 * output mode.
322 */
323 assert(0);
324 break;
325 }
326
327 chan_exts[i].monitor_timer_interval =
328 uchan->monitor_timer_interval;
329 chan_exts[i].blocking_timeout =
330 uchan->attr.u.s.blocking_timeout;
331
332 ret = get_ust_runtime_stats(session, uchan,
333 &discarded_events, &lost_packets);
334 if (ret < 0) {
335 break;
336 }
337 chan_exts[i].discarded_events = discarded_events;
338 chan_exts[i].lost_packets = lost_packets;
339 i++;
340 }
341 rcu_read_unlock();
342 break;
343 }
344 default:
345 break;
346 }
347
348 end:
349 if (ret < 0) {
350 return -LTTNG_ERR_FATAL;
351 } else {
352 return LTTNG_OK;
353 }
354 }
355
356 static void increment_extended_len(const char *filter_expression,
357 struct lttng_event_exclusion *exclusion, size_t *extended_len)
358 {
359 *extended_len += sizeof(struct lttcomm_event_extended_header);
360
361 if (filter_expression) {
362 *extended_len += strlen(filter_expression) + 1;
363 }
364
365 if (exclusion) {
366 *extended_len += exclusion->count * LTTNG_SYMBOL_NAME_LEN;
367 }
368 }
369
370 static void append_extended_info(const char *filter_expression,
371 struct lttng_event_exclusion *exclusion, void **extended_at)
372 {
373 struct lttcomm_event_extended_header extended_header;
374 size_t filter_len = 0;
375 size_t nb_exclusions = 0;
376
377 if (filter_expression) {
378 filter_len = strlen(filter_expression) + 1;
379 }
380
381 if (exclusion) {
382 nb_exclusions = exclusion->count;
383 }
384
385 /* Set header fields */
386 extended_header.filter_len = filter_len;
387 extended_header.nb_exclusions = nb_exclusions;
388
389 /* Copy header */
390 memcpy(*extended_at, &extended_header, sizeof(extended_header));
391 *extended_at += sizeof(extended_header);
392
393 /* Copy filter string */
394 if (filter_expression) {
395 memcpy(*extended_at, filter_expression, filter_len);
396 *extended_at += filter_len;
397 }
398
399 /* Copy exclusion names */
400 if (exclusion) {
401 size_t len = nb_exclusions * LTTNG_SYMBOL_NAME_LEN;
402
403 memcpy(*extended_at, &exclusion->names, len);
404 *extended_at += len;
405 }
406 }
407
408 /*
409 * Create a list of agent domain events.
410 *
411 * Return number of events in list on success or else a negative value.
412 */
413 static int list_lttng_agent_events(struct agent *agt,
414 struct lttng_event **events, size_t *total_size)
415 {
416 int i = 0, ret = 0;
417 unsigned int nb_event = 0;
418 struct agent_event *event;
419 struct lttng_event *tmp_events;
420 struct lttng_ht_iter iter;
421 size_t extended_len = 0;
422 void *extended_at;
423
424 assert(agt);
425 assert(events);
426
427 DBG3("Listing agent events");
428
429 rcu_read_lock();
430 nb_event = lttng_ht_get_count(agt->events);
431 rcu_read_unlock();
432 if (nb_event == 0) {
433 ret = nb_event;
434 *total_size = 0;
435 goto error;
436 }
437
438 /* Compute required extended infos size */
439 extended_len = nb_event * sizeof(struct lttcomm_event_extended_header);
440
441 /*
442 * This is only valid because the commands which add events are
443 * processed in the same thread as the listing.
444 */
445 rcu_read_lock();
446 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
447 increment_extended_len(event->filter_expression, NULL,
448 &extended_len);
449 }
450 rcu_read_unlock();
451
452 *total_size = nb_event * sizeof(*tmp_events) + extended_len;
453 tmp_events = zmalloc(*total_size);
454 if (!tmp_events) {
455 PERROR("zmalloc agent events session");
456 ret = -LTTNG_ERR_FATAL;
457 goto error;
458 }
459
460 extended_at = ((uint8_t *) tmp_events) +
461 nb_event * sizeof(struct lttng_event);
462
463 rcu_read_lock();
464 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
465 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
466 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
467 tmp_events[i].enabled = event->enabled;
468 tmp_events[i].loglevel = event->loglevel_value;
469 tmp_events[i].loglevel_type = event->loglevel_type;
470 i++;
471
472 /* Append extended info */
473 append_extended_info(event->filter_expression, NULL,
474 &extended_at);
475 }
476 rcu_read_unlock();
477
478 *events = tmp_events;
479 ret = nb_event;
480
481 error:
482 assert(nb_event == i);
483 return ret;
484 }
485
486 /*
487 * Create a list of ust global domain events.
488 */
489 static int list_lttng_ust_global_events(char *channel_name,
490 struct ltt_ust_domain_global *ust_global,
491 struct lttng_event **events, size_t *total_size)
492 {
493 int i = 0, ret = 0;
494 unsigned int nb_event = 0;
495 struct lttng_ht_iter iter;
496 struct lttng_ht_node_str *node;
497 struct ltt_ust_channel *uchan;
498 struct ltt_ust_event *uevent;
499 struct lttng_event *tmp;
500 size_t extended_len = 0;
501 void *extended_at;
502
503 DBG("Listing UST global events for channel %s", channel_name);
504
505 rcu_read_lock();
506
507 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
508 node = lttng_ht_iter_get_node_str(&iter);
509 if (node == NULL) {
510 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
511 goto end;
512 }
513
514 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
515
516 nb_event = lttng_ht_get_count(uchan->events);
517 if (nb_event == 0) {
518 ret = nb_event;
519 *total_size = 0;
520 goto end;
521 }
522
523 DBG3("Listing UST global %d events", nb_event);
524
525 /* Compute required extended infos size */
526 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
527 if (uevent->internal) {
528 nb_event--;
529 continue;
530 }
531
532 increment_extended_len(uevent->filter_expression,
533 uevent->exclusion, &extended_len);
534 }
535 if (nb_event == 0) {
536 /* All events are internal, skip. */
537 ret = 0;
538 *total_size = 0;
539 goto end;
540 }
541
542 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
543 tmp = zmalloc(*total_size);
544 if (tmp == NULL) {
545 ret = -LTTNG_ERR_FATAL;
546 goto end;
547 }
548
549 extended_at = ((uint8_t *) tmp) + nb_event * sizeof(struct lttng_event);
550
551 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
552 if (uevent->internal) {
553 /* This event should remain hidden from clients */
554 continue;
555 }
556 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
557 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
558 tmp[i].enabled = uevent->enabled;
559
560 switch (uevent->attr.instrumentation) {
561 case LTTNG_UST_TRACEPOINT:
562 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
563 break;
564 case LTTNG_UST_PROBE:
565 tmp[i].type = LTTNG_EVENT_PROBE;
566 break;
567 case LTTNG_UST_FUNCTION:
568 tmp[i].type = LTTNG_EVENT_FUNCTION;
569 break;
570 }
571
572 tmp[i].loglevel = uevent->attr.loglevel;
573 switch (uevent->attr.loglevel_type) {
574 case LTTNG_UST_LOGLEVEL_ALL:
575 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
576 break;
577 case LTTNG_UST_LOGLEVEL_RANGE:
578 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
579 break;
580 case LTTNG_UST_LOGLEVEL_SINGLE:
581 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
582 break;
583 }
584 if (uevent->filter) {
585 tmp[i].filter = 1;
586 }
587 if (uevent->exclusion) {
588 tmp[i].exclusion = 1;
589 }
590 i++;
591
592 /* Append extended info */
593 append_extended_info(uevent->filter_expression,
594 uevent->exclusion, &extended_at);
595 }
596
597 ret = nb_event;
598 *events = tmp;
599 end:
600 rcu_read_unlock();
601 return ret;
602 }
603
604 /*
605 * Fill lttng_event array of all kernel events in the channel.
606 */
607 static int list_lttng_kernel_events(char *channel_name,
608 struct ltt_kernel_session *kernel_session,
609 struct lttng_event **events, size_t *total_size)
610 {
611 int i = 0, ret;
612 unsigned int nb_event;
613 struct ltt_kernel_event *event;
614 struct ltt_kernel_channel *kchan;
615 size_t extended_len = 0;
616 void *extended_at;
617
618 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
619 if (kchan == NULL) {
620 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
621 goto error;
622 }
623
624 nb_event = kchan->event_count;
625
626 DBG("Listing events for channel %s", kchan->channel->name);
627
628 if (nb_event == 0) {
629 *total_size = 0;
630 *events = NULL;
631 goto end;
632 }
633
634 /* Compute required extended infos size */
635 cds_list_for_each_entry(event, &kchan->events_list.head, list) {
636 increment_extended_len(event->filter_expression, NULL,
637 &extended_len);
638 }
639
640 *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
641 *events = zmalloc(*total_size);
642 if (*events == NULL) {
643 ret = LTTNG_ERR_FATAL;
644 goto error;
645 }
646
647 extended_at = ((void *) *events) +
648 nb_event * sizeof(struct lttng_event);
649
650 /* Kernel channels */
651 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
652 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
653 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
654 (*events)[i].enabled = event->enabled;
655 (*events)[i].filter =
656 (unsigned char) !!event->filter_expression;
657
658 switch (event->event->instrumentation) {
659 case LTTNG_KERNEL_TRACEPOINT:
660 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
661 break;
662 case LTTNG_KERNEL_KRETPROBE:
663 (*events)[i].type = LTTNG_EVENT_FUNCTION;
664 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
665 sizeof(struct lttng_kernel_kprobe));
666 break;
667 case LTTNG_KERNEL_KPROBE:
668 (*events)[i].type = LTTNG_EVENT_PROBE;
669 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
670 sizeof(struct lttng_kernel_kprobe));
671 break;
672 case LTTNG_KERNEL_FUNCTION:
673 (*events)[i].type = LTTNG_EVENT_FUNCTION;
674 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
675 sizeof(struct lttng_kernel_function));
676 break;
677 case LTTNG_KERNEL_NOOP:
678 (*events)[i].type = LTTNG_EVENT_NOOP;
679 break;
680 case LTTNG_KERNEL_SYSCALL:
681 (*events)[i].type = LTTNG_EVENT_SYSCALL;
682 break;
683 case LTTNG_KERNEL_ALL:
684 assert(0);
685 break;
686 }
687 i++;
688
689 /* Append extended info */
690 append_extended_info(event->filter_expression, NULL,
691 &extended_at);
692 }
693
694 end:
695 return nb_event;
696
697 error:
698 /* Negate the error code to differentiate the size from an error */
699 return -ret;
700 }
701
702 /*
703 * Add URI so the consumer output object. Set the correct path depending on the
704 * domain adding the default trace directory.
705 */
706 static int add_uri_to_consumer(struct consumer_output *consumer,
707 struct lttng_uri *uri, enum lttng_domain_type domain,
708 const char *session_name)
709 {
710 int ret = LTTNG_OK;
711 const char *default_trace_dir;
712
713 assert(uri);
714
715 if (consumer == NULL) {
716 DBG("No consumer detected. Don't add URI. Stopping.");
717 ret = LTTNG_ERR_NO_CONSUMER;
718 goto error;
719 }
720
721 switch (domain) {
722 case LTTNG_DOMAIN_KERNEL:
723 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
724 break;
725 case LTTNG_DOMAIN_UST:
726 default_trace_dir = DEFAULT_UST_TRACE_DIR;
727 break;
728 default:
729 /*
730 * This case is possible is we try to add the URI to the global tracing
731 * session consumer object which in this case there is no subdir.
732 */
733 default_trace_dir = "";
734 }
735
736 switch (uri->dtype) {
737 case LTTNG_DST_IPV4:
738 case LTTNG_DST_IPV6:
739 DBG2("Setting network URI to consumer");
740
741 if (consumer->type == CONSUMER_DST_NET) {
742 if ((uri->stype == LTTNG_STREAM_CONTROL &&
743 consumer->dst.net.control_isset) ||
744 (uri->stype == LTTNG_STREAM_DATA &&
745 consumer->dst.net.data_isset)) {
746 ret = LTTNG_ERR_URL_EXIST;
747 goto error;
748 }
749 } else {
750 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
751 }
752
753 consumer->type = CONSUMER_DST_NET;
754
755 /* Set URI into consumer output object */
756 ret = consumer_set_network_uri(consumer, uri);
757 if (ret < 0) {
758 ret = -ret;
759 goto error;
760 } else if (ret == 1) {
761 /*
762 * URI was the same in the consumer so we do not append the subdir
763 * again so to not duplicate output dir.
764 */
765 ret = LTTNG_OK;
766 goto error;
767 }
768
769 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
770 ret = consumer_set_subdir(consumer, session_name);
771 if (ret < 0) {
772 ret = LTTNG_ERR_FATAL;
773 goto error;
774 }
775 }
776
777 if (uri->stype == LTTNG_STREAM_CONTROL) {
778 /* On a new subdir, reappend the default trace dir. */
779 strncat(consumer->subdir, default_trace_dir,
780 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
781 DBG3("Append domain trace name to subdir %s", consumer->subdir);
782 }
783
784 break;
785 case LTTNG_DST_PATH:
786 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
787 memset(consumer->dst.trace_path, 0,
788 sizeof(consumer->dst.trace_path));
789 /* Explicit length checks for strcpy and strcat. */
790 if (strlen(uri->dst.path) + strlen(default_trace_dir)
791 >= sizeof(consumer->dst.trace_path)) {
792 ret = LTTNG_ERR_FATAL;
793 goto error;
794 }
795 strcpy(consumer->dst.trace_path, uri->dst.path);
796 /* Append default trace dir */
797 strcat(consumer->dst.trace_path, default_trace_dir);
798 /* Flag consumer as local. */
799 consumer->type = CONSUMER_DST_LOCAL;
800 break;
801 }
802
803 ret = LTTNG_OK;
804
805 error:
806 return ret;
807 }
808
809 /*
810 * Init tracing by creating trace directory and sending fds kernel consumer.
811 */
812 static int init_kernel_tracing(struct ltt_kernel_session *session)
813 {
814 int ret = 0;
815 struct lttng_ht_iter iter;
816 struct consumer_socket *socket;
817
818 assert(session);
819
820 rcu_read_lock();
821
822 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
823 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
824 socket, node.node) {
825 pthread_mutex_lock(socket->lock);
826 ret = kernel_consumer_send_session(socket, session);
827 pthread_mutex_unlock(socket->lock);
828 if (ret < 0) {
829 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
830 goto error;
831 }
832 }
833 }
834
835 error:
836 rcu_read_unlock();
837 return ret;
838 }
839
840 /*
841 * Create a socket to the relayd using the URI.
842 *
843 * On success, the relayd_sock pointer is set to the created socket.
844 * Else, it's stays untouched and a lttcomm error code is returned.
845 */
846 static int create_connect_relayd(struct lttng_uri *uri,
847 struct lttcomm_relayd_sock **relayd_sock,
848 struct consumer_output *consumer)
849 {
850 int ret;
851 struct lttcomm_relayd_sock *rsock;
852
853 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
854 RELAYD_VERSION_COMM_MINOR);
855 if (!rsock) {
856 ret = LTTNG_ERR_FATAL;
857 goto error;
858 }
859
860 /*
861 * Connect to relayd so we can proceed with a session creation. This call
862 * can possibly block for an arbitrary amount of time to set the health
863 * state to be in poll execution.
864 */
865 health_poll_entry();
866 ret = relayd_connect(rsock);
867 health_poll_exit();
868 if (ret < 0) {
869 ERR("Unable to reach lttng-relayd");
870 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
871 goto free_sock;
872 }
873
874 /* Create socket for control stream. */
875 if (uri->stype == LTTNG_STREAM_CONTROL) {
876 DBG3("Creating relayd stream socket from URI");
877
878 /* Check relayd version */
879 ret = relayd_version_check(rsock);
880 if (ret < 0) {
881 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
882 goto close_sock;
883 }
884 consumer->relay_major_version = rsock->major;
885 consumer->relay_minor_version = rsock->minor;
886 } else if (uri->stype == LTTNG_STREAM_DATA) {
887 DBG3("Creating relayd data socket from URI");
888 } else {
889 /* Command is not valid */
890 ERR("Relayd invalid stream type: %d", uri->stype);
891 ret = LTTNG_ERR_INVALID;
892 goto close_sock;
893 }
894
895 *relayd_sock = rsock;
896
897 return LTTNG_OK;
898
899 close_sock:
900 /* The returned value is not useful since we are on an error path. */
901 (void) relayd_close(rsock);
902 free_sock:
903 free(rsock);
904 error:
905 return ret;
906 }
907
908 /*
909 * Connect to the relayd using URI and send the socket to the right consumer.
910 *
911 * The consumer socket lock must be held by the caller.
912 */
913 static int send_consumer_relayd_socket(enum lttng_domain_type domain,
914 unsigned int session_id, struct lttng_uri *relayd_uri,
915 struct consumer_output *consumer,
916 struct consumer_socket *consumer_sock,
917 char *session_name, char *hostname, int session_live_timer)
918 {
919 int ret;
920 struct lttcomm_relayd_sock *rsock = NULL;
921
922 /* Connect to relayd and make version check if uri is the control. */
923 ret = create_connect_relayd(relayd_uri, &rsock, consumer);
924 if (ret != LTTNG_OK) {
925 goto relayd_comm_error;
926 }
927 assert(rsock);
928
929 /* Set the network sequence index if not set. */
930 if (consumer->net_seq_index == (uint64_t) -1ULL) {
931 pthread_mutex_lock(&relayd_net_seq_idx_lock);
932 /*
933 * Increment net_seq_idx because we are about to transfer the
934 * new relayd socket to the consumer.
935 * Assign unique key so the consumer can match streams.
936 */
937 consumer->net_seq_index = ++relayd_net_seq_idx;
938 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
939 }
940
941 /* Send relayd socket to consumer. */
942 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
943 relayd_uri->stype, session_id,
944 session_name, hostname, session_live_timer);
945 if (ret < 0) {
946 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
947 goto close_sock;
948 }
949
950 /* Flag that the corresponding socket was sent. */
951 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
952 consumer_sock->control_sock_sent = 1;
953 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
954 consumer_sock->data_sock_sent = 1;
955 }
956
957 ret = LTTNG_OK;
958
959 /*
960 * Close socket which was dup on the consumer side. The session daemon does
961 * NOT keep track of the relayd socket(s) once transfer to the consumer.
962 */
963
964 close_sock:
965 if (ret != LTTNG_OK) {
966 /*
967 * The consumer output for this session should not be used anymore
968 * since the relayd connection failed thus making any tracing or/and
969 * streaming not usable.
970 */
971 consumer->enabled = 0;
972 }
973 (void) relayd_close(rsock);
974 free(rsock);
975
976 relayd_comm_error:
977 return ret;
978 }
979
980 /*
981 * Send both relayd sockets to a specific consumer and domain. This is a
982 * helper function to facilitate sending the information to the consumer for a
983 * session.
984 *
985 * The consumer socket lock must be held by the caller.
986 */
987 static int send_consumer_relayd_sockets(enum lttng_domain_type domain,
988 unsigned int session_id, struct consumer_output *consumer,
989 struct consumer_socket *sock, char *session_name,
990 char *hostname, int session_live_timer)
991 {
992 int ret = LTTNG_OK;
993
994 assert(consumer);
995 assert(sock);
996
997 /* Sending control relayd socket. */
998 if (!sock->control_sock_sent) {
999 ret = send_consumer_relayd_socket(domain, session_id,
1000 &consumer->dst.net.control, consumer, sock,
1001 session_name, hostname, session_live_timer);
1002 if (ret != LTTNG_OK) {
1003 goto error;
1004 }
1005 }
1006
1007 /* Sending data relayd socket. */
1008 if (!sock->data_sock_sent) {
1009 ret = send_consumer_relayd_socket(domain, session_id,
1010 &consumer->dst.net.data, consumer, sock,
1011 session_name, hostname, session_live_timer);
1012 if (ret != LTTNG_OK) {
1013 goto error;
1014 }
1015 }
1016
1017 error:
1018 return ret;
1019 }
1020
1021 /*
1022 * Setup relayd connections for a tracing session. First creates the socket to
1023 * the relayd and send them to the right domain consumer. Consumer type MUST be
1024 * network.
1025 */
1026 int cmd_setup_relayd(struct ltt_session *session)
1027 {
1028 int ret = LTTNG_OK;
1029 struct ltt_ust_session *usess;
1030 struct ltt_kernel_session *ksess;
1031 struct consumer_socket *socket;
1032 struct lttng_ht_iter iter;
1033
1034 assert(session);
1035
1036 usess = session->ust_session;
1037 ksess = session->kernel_session;
1038
1039 DBG("Setting relayd for session %s", session->name);
1040
1041 rcu_read_lock();
1042
1043 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
1044 && usess->consumer->enabled) {
1045 /* For each consumer socket, send relayd sockets */
1046 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
1047 socket, node.node) {
1048 pthread_mutex_lock(socket->lock);
1049 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
1050 usess->consumer, socket,
1051 session->name, session->hostname,
1052 session->live_timer);
1053 pthread_mutex_unlock(socket->lock);
1054 if (ret != LTTNG_OK) {
1055 goto error;
1056 }
1057 /* Session is now ready for network streaming. */
1058 session->net_handle = 1;
1059 }
1060 session->consumer->relay_major_version =
1061 usess->consumer->relay_major_version;
1062 session->consumer->relay_minor_version =
1063 usess->consumer->relay_minor_version;
1064 }
1065
1066 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
1067 && ksess->consumer->enabled) {
1068 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
1069 socket, node.node) {
1070 pthread_mutex_lock(socket->lock);
1071 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
1072 ksess->consumer, socket,
1073 session->name, session->hostname,
1074 session->live_timer);
1075 pthread_mutex_unlock(socket->lock);
1076 if (ret != LTTNG_OK) {
1077 goto error;
1078 }
1079 /* Session is now ready for network streaming. */
1080 session->net_handle = 1;
1081 }
1082 session->consumer->relay_major_version =
1083 ksess->consumer->relay_major_version;
1084 session->consumer->relay_minor_version =
1085 ksess->consumer->relay_minor_version;
1086 }
1087
1088 error:
1089 rcu_read_unlock();
1090 return ret;
1091 }
1092
1093 /*
1094 * Start a kernel session by opening all necessary streams.
1095 */
1096 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
1097 {
1098 int ret;
1099 struct ltt_kernel_channel *kchan;
1100
1101 /* Open kernel metadata */
1102 if (ksess->metadata == NULL && ksess->output_traces) {
1103 ret = kernel_open_metadata(ksess);
1104 if (ret < 0) {
1105 ret = LTTNG_ERR_KERN_META_FAIL;
1106 goto error;
1107 }
1108 }
1109
1110 /* Open kernel metadata stream */
1111 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
1112 ret = kernel_open_metadata_stream(ksess);
1113 if (ret < 0) {
1114 ERR("Kernel create metadata stream failed");
1115 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1116 goto error;
1117 }
1118 }
1119
1120 /* For each channel */
1121 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
1122 if (kchan->stream_count == 0) {
1123 ret = kernel_open_channel_stream(kchan);
1124 if (ret < 0) {
1125 ret = LTTNG_ERR_KERN_STREAM_FAIL;
1126 goto error;
1127 }
1128 /* Update the stream global counter */
1129 ksess->stream_count_global += ret;
1130 }
1131 }
1132
1133 /* Setup kernel consumer socket and send fds to it */
1134 ret = init_kernel_tracing(ksess);
1135 if (ret != 0) {
1136 ret = LTTNG_ERR_KERN_START_FAIL;
1137 goto error;
1138 }
1139
1140 /* This start the kernel tracing */
1141 ret = kernel_start_session(ksess);
1142 if (ret < 0) {
1143 ret = LTTNG_ERR_KERN_START_FAIL;
1144 goto error;
1145 }
1146
1147 /* Quiescent wait after starting trace */
1148 kernel_wait_quiescent(kernel_tracer_fd);
1149
1150 ksess->active = 1;
1151
1152 ret = LTTNG_OK;
1153
1154 error:
1155 return ret;
1156 }
1157
1158 /*
1159 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1160 */
1161 int cmd_disable_channel(struct ltt_session *session,
1162 enum lttng_domain_type domain, char *channel_name)
1163 {
1164 int ret;
1165 struct ltt_ust_session *usess;
1166
1167 usess = session->ust_session;
1168
1169 rcu_read_lock();
1170
1171 switch (domain) {
1172 case LTTNG_DOMAIN_KERNEL:
1173 {
1174 ret = channel_kernel_disable(session->kernel_session,
1175 channel_name);
1176 if (ret != LTTNG_OK) {
1177 goto error;
1178 }
1179
1180 kernel_wait_quiescent(kernel_tracer_fd);
1181 break;
1182 }
1183 case LTTNG_DOMAIN_UST:
1184 {
1185 struct ltt_ust_channel *uchan;
1186 struct lttng_ht *chan_ht;
1187
1188 chan_ht = usess->domain_global.channels;
1189
1190 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
1191 if (uchan == NULL) {
1192 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1193 goto error;
1194 }
1195
1196 ret = channel_ust_disable(usess, uchan);
1197 if (ret != LTTNG_OK) {
1198 goto error;
1199 }
1200 break;
1201 }
1202 default:
1203 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1204 goto error;
1205 }
1206
1207 ret = LTTNG_OK;
1208
1209 error:
1210 rcu_read_unlock();
1211 return ret;
1212 }
1213
1214 /*
1215 * Command LTTNG_TRACK_PID processed by the client thread.
1216 *
1217 * Called with session lock held.
1218 */
1219 int cmd_track_pid(struct ltt_session *session, enum lttng_domain_type domain,
1220 int pid)
1221 {
1222 int ret;
1223
1224 rcu_read_lock();
1225
1226 switch (domain) {
1227 case LTTNG_DOMAIN_KERNEL:
1228 {
1229 struct ltt_kernel_session *ksess;
1230
1231 ksess = session->kernel_session;
1232
1233 ret = kernel_track_pid(ksess, pid);
1234 if (ret != LTTNG_OK) {
1235 goto error;
1236 }
1237
1238 kernel_wait_quiescent(kernel_tracer_fd);
1239 break;
1240 }
1241 case LTTNG_DOMAIN_UST:
1242 {
1243 struct ltt_ust_session *usess;
1244
1245 usess = session->ust_session;
1246
1247 ret = trace_ust_track_pid(usess, pid);
1248 if (ret != LTTNG_OK) {
1249 goto error;
1250 }
1251 break;
1252 }
1253 default:
1254 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1255 goto error;
1256 }
1257
1258 ret = LTTNG_OK;
1259
1260 error:
1261 rcu_read_unlock();
1262 return ret;
1263 }
1264
1265 /*
1266 * Command LTTNG_UNTRACK_PID processed by the client thread.
1267 *
1268 * Called with session lock held.
1269 */
1270 int cmd_untrack_pid(struct ltt_session *session, enum lttng_domain_type domain,
1271 int pid)
1272 {
1273 int ret;
1274
1275 rcu_read_lock();
1276
1277 switch (domain) {
1278 case LTTNG_DOMAIN_KERNEL:
1279 {
1280 struct ltt_kernel_session *ksess;
1281
1282 ksess = session->kernel_session;
1283
1284 ret = kernel_untrack_pid(ksess, pid);
1285 if (ret != LTTNG_OK) {
1286 goto error;
1287 }
1288
1289 kernel_wait_quiescent(kernel_tracer_fd);
1290 break;
1291 }
1292 case LTTNG_DOMAIN_UST:
1293 {
1294 struct ltt_ust_session *usess;
1295
1296 usess = session->ust_session;
1297
1298 ret = trace_ust_untrack_pid(usess, pid);
1299 if (ret != LTTNG_OK) {
1300 goto error;
1301 }
1302 break;
1303 }
1304 default:
1305 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1306 goto error;
1307 }
1308
1309 ret = LTTNG_OK;
1310
1311 error:
1312 rcu_read_unlock();
1313 return ret;
1314 }
1315
1316 /*
1317 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1318 *
1319 * The wpipe arguments is used as a notifier for the kernel thread.
1320 */
1321 int cmd_enable_channel(struct ltt_session *session,
1322 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1323 {
1324 int ret;
1325 struct ltt_ust_session *usess = session->ust_session;
1326 struct lttng_ht *chan_ht;
1327 size_t len;
1328
1329 assert(session);
1330 assert(attr);
1331 assert(domain);
1332
1333 len = lttng_strnlen(attr->name, sizeof(attr->name));
1334
1335 /* Validate channel name */
1336 if (attr->name[0] == '.' ||
1337 memchr(attr->name, '/', len) != NULL) {
1338 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1339 goto end;
1340 }
1341
1342 DBG("Enabling channel %s for session %s", attr->name, session->name);
1343
1344 rcu_read_lock();
1345
1346 /*
1347 * Don't try to enable a channel if the session has been started at
1348 * some point in time before. The tracer does not allow it.
1349 */
1350 if (session->has_been_started) {
1351 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1352 goto error;
1353 }
1354
1355 /*
1356 * If the session is a live session, remove the switch timer, the
1357 * live timer does the same thing but sends also synchronisation
1358 * beacons for inactive streams.
1359 */
1360 if (session->live_timer > 0) {
1361 attr->attr.live_timer_interval = session->live_timer;
1362 attr->attr.switch_timer_interval = 0;
1363 }
1364
1365 /* Check for feature support */
1366 switch (domain->type) {
1367 case LTTNG_DOMAIN_KERNEL:
1368 {
1369 if (kernel_supports_ring_buffer_snapshot_sample_positions(kernel_tracer_fd) != 1) {
1370 /* Sampling position of buffer is not supported */
1371 WARN("Kernel tracer does not support buffer monitoring. "
1372 "Setting the monitor interval timer to 0 "
1373 "(disabled) for channel '%s' of session '%s'",
1374 attr-> name, session->name);
1375 lttng_channel_set_monitor_timer_interval(attr, 0);
1376 }
1377 break;
1378 }
1379 case LTTNG_DOMAIN_UST:
1380 case LTTNG_DOMAIN_JUL:
1381 case LTTNG_DOMAIN_LOG4J:
1382 case LTTNG_DOMAIN_PYTHON:
1383 break;
1384 default:
1385 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1386 goto error;
1387 }
1388
1389 switch (domain->type) {
1390 case LTTNG_DOMAIN_KERNEL:
1391 {
1392 struct ltt_kernel_channel *kchan;
1393
1394 kchan = trace_kernel_get_channel_by_name(attr->name,
1395 session->kernel_session);
1396 if (kchan == NULL) {
1397 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1398 if (attr->name[0] != '\0') {
1399 session->kernel_session->has_non_default_channel = 1;
1400 }
1401 } else {
1402 ret = channel_kernel_enable(session->kernel_session, kchan);
1403 }
1404
1405 if (ret != LTTNG_OK) {
1406 goto error;
1407 }
1408
1409 kernel_wait_quiescent(kernel_tracer_fd);
1410 break;
1411 }
1412 case LTTNG_DOMAIN_UST:
1413 case LTTNG_DOMAIN_JUL:
1414 case LTTNG_DOMAIN_LOG4J:
1415 case LTTNG_DOMAIN_PYTHON:
1416 {
1417 struct ltt_ust_channel *uchan;
1418
1419 /*
1420 * FIXME
1421 *
1422 * Current agent implementation limitations force us to allow
1423 * only one channel at once in "agent" subdomains. Each
1424 * subdomain has a default channel name which must be strictly
1425 * adhered to.
1426 */
1427 if (domain->type == LTTNG_DOMAIN_JUL) {
1428 if (strncmp(attr->name, DEFAULT_JUL_CHANNEL_NAME,
1429 LTTNG_SYMBOL_NAME_LEN)) {
1430 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1431 goto error;
1432 }
1433 } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
1434 if (strncmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME,
1435 LTTNG_SYMBOL_NAME_LEN)) {
1436 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1437 goto error;
1438 }
1439 } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
1440 if (strncmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME,
1441 LTTNG_SYMBOL_NAME_LEN)) {
1442 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1443 goto error;
1444 }
1445 }
1446
1447 chan_ht = usess->domain_global.channels;
1448
1449 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1450 if (uchan == NULL) {
1451 ret = channel_ust_create(usess, attr, domain->buf_type);
1452 if (attr->name[0] != '\0') {
1453 usess->has_non_default_channel = 1;
1454 }
1455 } else {
1456 ret = channel_ust_enable(usess, uchan);
1457 }
1458 break;
1459 }
1460 default:
1461 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1462 goto error;
1463 }
1464
1465 error:
1466 rcu_read_unlock();
1467 end:
1468 return ret;
1469 }
1470
1471 /*
1472 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1473 */
1474 int cmd_disable_event(struct ltt_session *session,
1475 enum lttng_domain_type domain, char *channel_name,
1476 struct lttng_event *event)
1477 {
1478 int ret;
1479 char *event_name;
1480
1481 DBG("Disable event command for event \'%s\'", event->name);
1482
1483 event_name = event->name;
1484
1485 /* Error out on unhandled search criteria */
1486 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1487 || event->pid || event->filter || event->exclusion) {
1488 ret = LTTNG_ERR_UNK;
1489 goto error;
1490 }
1491
1492 rcu_read_lock();
1493
1494 switch (domain) {
1495 case LTTNG_DOMAIN_KERNEL:
1496 {
1497 struct ltt_kernel_channel *kchan;
1498 struct ltt_kernel_session *ksess;
1499
1500 ksess = session->kernel_session;
1501
1502 /*
1503 * If a non-default channel has been created in the
1504 * session, explicitely require that -c chan_name needs
1505 * to be provided.
1506 */
1507 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1508 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1509 goto error_unlock;
1510 }
1511
1512 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1513 if (kchan == NULL) {
1514 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1515 goto error_unlock;
1516 }
1517
1518 switch (event->type) {
1519 case LTTNG_EVENT_ALL:
1520 case LTTNG_EVENT_TRACEPOINT:
1521 case LTTNG_EVENT_SYSCALL:
1522 case LTTNG_EVENT_PROBE:
1523 case LTTNG_EVENT_FUNCTION:
1524 case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
1525 if (event_name[0] == '\0') {
1526 ret = event_kernel_disable_event(kchan,
1527 NULL, event->type);
1528 } else {
1529 ret = event_kernel_disable_event(kchan,
1530 event_name, event->type);
1531 }
1532 if (ret != LTTNG_OK) {
1533 goto error_unlock;
1534 }
1535 break;
1536 default:
1537 ret = LTTNG_ERR_UNK;
1538 goto error_unlock;
1539 }
1540
1541 kernel_wait_quiescent(kernel_tracer_fd);
1542 break;
1543 }
1544 case LTTNG_DOMAIN_UST:
1545 {
1546 struct ltt_ust_channel *uchan;
1547 struct ltt_ust_session *usess;
1548
1549 usess = session->ust_session;
1550
1551 if (validate_ust_event_name(event_name)) {
1552 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1553 goto error_unlock;
1554 }
1555
1556 /*
1557 * If a non-default channel has been created in the
1558 * session, explicitly require that -c chan_name needs
1559 * to be provided.
1560 */
1561 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1562 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1563 goto error_unlock;
1564 }
1565
1566 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1567 channel_name);
1568 if (uchan == NULL) {
1569 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1570 goto error_unlock;
1571 }
1572
1573 switch (event->type) {
1574 case LTTNG_EVENT_ALL:
1575 /*
1576 * An empty event name means that everything
1577 * should be disabled.
1578 */
1579 if (event->name[0] == '\0') {
1580 ret = event_ust_disable_all_tracepoints(usess, uchan);
1581 } else {
1582 ret = event_ust_disable_tracepoint(usess, uchan,
1583 event_name);
1584 }
1585 if (ret != LTTNG_OK) {
1586 goto error_unlock;
1587 }
1588 break;
1589 default:
1590 ret = LTTNG_ERR_UNK;
1591 goto error_unlock;
1592 }
1593
1594 DBG3("Disable UST event %s in channel %s completed", event_name,
1595 channel_name);
1596 break;
1597 }
1598 case LTTNG_DOMAIN_LOG4J:
1599 case LTTNG_DOMAIN_JUL:
1600 case LTTNG_DOMAIN_PYTHON:
1601 {
1602 struct agent *agt;
1603 struct ltt_ust_session *usess = session->ust_session;
1604
1605 assert(usess);
1606
1607 switch (event->type) {
1608 case LTTNG_EVENT_ALL:
1609 break;
1610 default:
1611 ret = LTTNG_ERR_UNK;
1612 goto error_unlock;
1613 }
1614
1615 agt = trace_ust_find_agent(usess, domain);
1616 if (!agt) {
1617 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1618 goto error_unlock;
1619 }
1620 /*
1621 * An empty event name means that everything
1622 * should be disabled.
1623 */
1624 if (event->name[0] == '\0') {
1625 ret = event_agent_disable_all(usess, agt);
1626 } else {
1627 ret = event_agent_disable(usess, agt, event_name);
1628 }
1629 if (ret != LTTNG_OK) {
1630 goto error_unlock;
1631 }
1632
1633 break;
1634 }
1635 default:
1636 ret = LTTNG_ERR_UND;
1637 goto error_unlock;
1638 }
1639
1640 ret = LTTNG_OK;
1641
1642 error_unlock:
1643 rcu_read_unlock();
1644 error:
1645 return ret;
1646 }
1647
1648 /*
1649 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1650 */
1651 int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
1652 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1653 {
1654 int ret, chan_kern_created = 0, chan_ust_created = 0;
1655 char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
1656
1657 if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1658 app_ctx_provider_name = ctx->u.app_ctx.provider_name;
1659 app_ctx_name = ctx->u.app_ctx.ctx_name;
1660 }
1661
1662 switch (domain) {
1663 case LTTNG_DOMAIN_KERNEL:
1664 assert(session->kernel_session);
1665
1666 if (session->kernel_session->channel_count == 0) {
1667 /* Create default channel */
1668 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1669 if (ret != LTTNG_OK) {
1670 goto error;
1671 }
1672 chan_kern_created = 1;
1673 }
1674 /* Add kernel context to kernel tracer */
1675 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1676 if (ret != LTTNG_OK) {
1677 goto error;
1678 }
1679 break;
1680 case LTTNG_DOMAIN_JUL:
1681 case LTTNG_DOMAIN_LOG4J:
1682 {
1683 /*
1684 * Validate channel name.
1685 * If no channel name is given and the domain is JUL or LOG4J,
1686 * set it to the appropriate domain-specific channel name. If
1687 * a name is provided but does not match the expexted channel
1688 * name, return an error.
1689 */
1690 if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
1691 strcmp(channel_name,
1692 DEFAULT_JUL_CHANNEL_NAME)) {
1693 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1694 goto error;
1695 } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
1696 strcmp(channel_name,
1697 DEFAULT_LOG4J_CHANNEL_NAME)) {
1698 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1699 goto error;
1700 }
1701 /* break is _not_ missing here. */
1702 }
1703 case LTTNG_DOMAIN_UST:
1704 {
1705 struct ltt_ust_session *usess = session->ust_session;
1706 unsigned int chan_count;
1707
1708 assert(usess);
1709
1710 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1711 if (chan_count == 0) {
1712 struct lttng_channel *attr;
1713 /* Create default channel */
1714 attr = channel_new_default_attr(domain, usess->buffer_type);
1715 if (attr == NULL) {
1716 ret = LTTNG_ERR_FATAL;
1717 goto error;
1718 }
1719
1720 ret = channel_ust_create(usess, attr, usess->buffer_type);
1721 if (ret != LTTNG_OK) {
1722 free(attr);
1723 goto error;
1724 }
1725 channel_attr_destroy(attr);
1726 chan_ust_created = 1;
1727 }
1728
1729 ret = context_ust_add(usess, domain, ctx, channel_name);
1730 free(app_ctx_provider_name);
1731 free(app_ctx_name);
1732 app_ctx_name = NULL;
1733 app_ctx_provider_name = NULL;
1734 if (ret != LTTNG_OK) {
1735 goto error;
1736 }
1737 break;
1738 }
1739 default:
1740 ret = LTTNG_ERR_UND;
1741 goto error;
1742 }
1743
1744 ret = LTTNG_OK;
1745 goto end;
1746
1747 error:
1748 if (chan_kern_created) {
1749 struct ltt_kernel_channel *kchan =
1750 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1751 session->kernel_session);
1752 /* Created previously, this should NOT fail. */
1753 assert(kchan);
1754 kernel_destroy_channel(kchan);
1755 }
1756
1757 if (chan_ust_created) {
1758 struct ltt_ust_channel *uchan =
1759 trace_ust_find_channel_by_name(
1760 session->ust_session->domain_global.channels,
1761 DEFAULT_CHANNEL_NAME);
1762 /* Created previously, this should NOT fail. */
1763 assert(uchan);
1764 /* Remove from the channel list of the session. */
1765 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1766 uchan);
1767 trace_ust_destroy_channel(uchan);
1768 }
1769 end:
1770 free(app_ctx_provider_name);
1771 free(app_ctx_name);
1772 return ret;
1773 }
1774
1775 static inline bool name_starts_with(const char *name, const char *prefix)
1776 {
1777 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1778
1779 return !strncmp(name, prefix, max_cmp_len);
1780 }
1781
1782 /* Perform userspace-specific event name validation */
1783 static int validate_ust_event_name(const char *name)
1784 {
1785 int ret = 0;
1786
1787 if (!name) {
1788 ret = -1;
1789 goto end;
1790 }
1791
1792 /*
1793 * Check name against all internal UST event component namespaces used
1794 * by the agents.
1795 */
1796 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1797 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1798 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1799 ret = -1;
1800 }
1801
1802 end:
1803 return ret;
1804 }
1805
1806 /*
1807 * Internal version of cmd_enable_event() with a supplemental
1808 * "internal_event" flag which is used to enable internal events which should
1809 * be hidden from clients. Such events are used in the agent implementation to
1810 * enable the events through which all "agent" events are funeled.
1811 */
1812 static int _cmd_enable_event(struct ltt_session *session,
1813 struct lttng_domain *domain,
1814 char *channel_name, struct lttng_event *event,
1815 char *filter_expression,
1816 struct lttng_filter_bytecode *filter,
1817 struct lttng_event_exclusion *exclusion,
1818 int wpipe, bool internal_event)
1819 {
1820 int ret = 0, channel_created = 0;
1821 struct lttng_channel *attr = NULL;
1822
1823 assert(session);
1824 assert(event);
1825 assert(channel_name);
1826
1827 /* If we have a filter, we must have its filter expression */
1828 assert(!(!!filter_expression ^ !!filter));
1829
1830 /* Normalize event name as a globbing pattern */
1831 strutils_normalize_star_glob_pattern(event->name);
1832
1833 /* Normalize exclusion names as globbing patterns */
1834 if (exclusion) {
1835 size_t i;
1836
1837 for (i = 0; i < exclusion->count; i++) {
1838 char *name = LTTNG_EVENT_EXCLUSION_NAME_AT(exclusion, i);
1839
1840 strutils_normalize_star_glob_pattern(name);
1841 }
1842 }
1843
1844 DBG("Enable event command for event \'%s\'", event->name);
1845
1846 rcu_read_lock();
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 channel_attr_destroy(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 lttng_channel_extended);
2965 struct lttng_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
3411 ret = lseek(fd, 0, SEEK_SET);
3412 if (ret < 0) {
3413 PERROR("lseek");
3414 goto end;
3415 }
3416
3417 ret = ftruncate(fd, 0);
3418 if (ret < 0) {
3419 PERROR("ftruncate");
3420 goto end;
3421 }
3422
3423 end:
3424 return ret;
3425 }
3426
3427 static
3428 int ust_regenerate_metadata(struct ltt_ust_session *usess)
3429 {
3430 int ret = 0;
3431 struct buffer_reg_uid *uid_reg = NULL;
3432 struct buffer_reg_session *session_reg = NULL;
3433
3434 rcu_read_lock();
3435 cds_list_for_each_entry(uid_reg, &usess->buffer_reg_uid_list, lnode) {
3436 struct ust_registry_session *registry;
3437 struct ust_registry_channel *chan;
3438 struct lttng_ht_iter iter_chan;
3439
3440 session_reg = uid_reg->registry;
3441 registry = session_reg->reg.ust;
3442
3443 pthread_mutex_lock(&registry->lock);
3444 registry->metadata_len_sent = 0;
3445 memset(registry->metadata, 0, registry->metadata_alloc_len);
3446 registry->metadata_len = 0;
3447 registry->metadata_version++;
3448 if (registry->metadata_fd > 0) {
3449 /* Clear the metadata file's content. */
3450 ret = clear_metadata_file(registry->metadata_fd);
3451 if (ret) {
3452 pthread_mutex_unlock(&registry->lock);
3453 goto end;
3454 }
3455 }
3456
3457 ret = ust_metadata_session_statedump(registry, NULL,
3458 registry->major, registry->minor);
3459 if (ret) {
3460 pthread_mutex_unlock(&registry->lock);
3461 ERR("Failed to generate session metadata (err = %d)",
3462 ret);
3463 goto end;
3464 }
3465 cds_lfht_for_each_entry(registry->channels->ht, &iter_chan.iter,
3466 chan, node.node) {
3467 struct ust_registry_event *event;
3468 struct lttng_ht_iter iter_event;
3469
3470 ret = ust_metadata_channel_statedump(registry, chan);
3471 if (ret) {
3472 pthread_mutex_unlock(&registry->lock);
3473 ERR("Failed to generate channel metadata "
3474 "(err = %d)", ret);
3475 goto end;
3476 }
3477 cds_lfht_for_each_entry(chan->ht->ht, &iter_event.iter,
3478 event, node.node) {
3479 ret = ust_metadata_event_statedump(registry,
3480 chan, event);
3481 if (ret) {
3482 pthread_mutex_unlock(&registry->lock);
3483 ERR("Failed to generate event metadata "
3484 "(err = %d)", ret);
3485 goto end;
3486 }
3487 }
3488 }
3489 pthread_mutex_unlock(&registry->lock);
3490 }
3491
3492 end:
3493 rcu_read_unlock();
3494 return ret;
3495 }
3496
3497 /*
3498 * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
3499 *
3500 * Ask the consumer to truncate the existing metadata file(s) and
3501 * then regenerate the metadata. Live and per-pid sessions are not
3502 * supported and return an error.
3503 *
3504 * Return 0 on success or else a LTTNG_ERR code.
3505 */
3506 int cmd_regenerate_metadata(struct ltt_session *session)
3507 {
3508 int ret;
3509
3510 assert(session);
3511
3512 ret = check_regenerate_metadata_support(session);
3513 if (ret) {
3514 goto end;
3515 }
3516
3517 if (session->kernel_session) {
3518 ret = kernctl_session_regenerate_metadata(
3519 session->kernel_session->fd);
3520 if (ret < 0) {
3521 ERR("Failed to regenerate the kernel metadata");
3522 goto end;
3523 }
3524 }
3525
3526 if (session->ust_session) {
3527 ret = ust_regenerate_metadata(session->ust_session);
3528 if (ret < 0) {
3529 ERR("Failed to regenerate the UST metadata");
3530 goto end;
3531 }
3532 }
3533 DBG("Cmd metadata regenerate for session %s", session->name);
3534 ret = LTTNG_OK;
3535
3536 end:
3537 return ret;
3538 }
3539
3540 /*
3541 * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
3542 *
3543 * Ask the tracer to regenerate a new statedump.
3544 *
3545 * Return 0 on success or else a LTTNG_ERR code.
3546 */
3547 int cmd_regenerate_statedump(struct ltt_session *session)
3548 {
3549 int ret;
3550
3551 assert(session);
3552
3553 if (!session->active) {
3554 ret = LTTNG_ERR_SESSION_NOT_STARTED;
3555 goto end;
3556 }
3557
3558 if (session->kernel_session) {
3559 ret = kernctl_session_regenerate_statedump(
3560 session->kernel_session->fd);
3561 /*
3562 * Currently, the statedump in kernel can only fail if out
3563 * of memory.
3564 */
3565 if (ret < 0) {
3566 if (ret == -ENOMEM) {
3567 ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
3568 } else {
3569 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
3570 }
3571 ERR("Failed to regenerate the kernel statedump");
3572 goto end;
3573 }
3574 }
3575
3576 if (session->ust_session) {
3577 ret = ust_app_regenerate_statedump_all(session->ust_session);
3578 /*
3579 * Currently, the statedump in UST always returns 0.
3580 */
3581 if (ret < 0) {
3582 ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
3583 ERR("Failed to regenerate the UST statedump");
3584 goto end;
3585 }
3586 }
3587 DBG("Cmd regenerate statedump for session %s", session->name);
3588 ret = LTTNG_OK;
3589
3590 end:
3591 return ret;
3592 }
3593
3594 int cmd_register_trigger(struct command_ctx *cmd_ctx, int sock,
3595 struct notification_thread_handle *notification_thread)
3596 {
3597 int ret;
3598 size_t trigger_len;
3599 ssize_t sock_recv_len;
3600 struct lttng_trigger *trigger = NULL;
3601 struct lttng_buffer_view view;
3602 struct lttng_dynamic_buffer trigger_buffer;
3603
3604 lttng_dynamic_buffer_init(&trigger_buffer);
3605 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
3606 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
3607 if (ret) {
3608 ret = LTTNG_ERR_NOMEM;
3609 goto end;
3610 }
3611
3612 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
3613 trigger_len);
3614 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
3615 ERR("Failed to receive \"register trigger\" command payload");
3616 /* TODO: should this be a new error enum ? */
3617 ret = LTTNG_ERR_INVALID_TRIGGER;
3618 goto end;
3619 }
3620
3621 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
3622 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
3623 trigger_len) {
3624 ERR("Invalid trigger payload received in \"register trigger\" command");
3625 ret = LTTNG_ERR_INVALID_TRIGGER;
3626 goto end;
3627 }
3628
3629 ret = notification_thread_command_register_trigger(notification_thread,
3630 trigger);
3631 /* Ownership of trigger was transferred. */
3632 trigger = NULL;
3633 end:
3634 lttng_trigger_destroy(trigger);
3635 lttng_dynamic_buffer_reset(&trigger_buffer);
3636 return ret;
3637 }
3638
3639 int cmd_unregister_trigger(struct command_ctx *cmd_ctx, int sock,
3640 struct notification_thread_handle *notification_thread)
3641 {
3642 int ret;
3643 size_t trigger_len;
3644 ssize_t sock_recv_len;
3645 struct lttng_trigger *trigger = NULL;
3646 struct lttng_buffer_view view;
3647 struct lttng_dynamic_buffer trigger_buffer;
3648
3649 lttng_dynamic_buffer_init(&trigger_buffer);
3650 trigger_len = (size_t) cmd_ctx->lsm->u.trigger.length;
3651 ret = lttng_dynamic_buffer_set_size(&trigger_buffer, trigger_len);
3652 if (ret) {
3653 ret = LTTNG_ERR_NOMEM;
3654 goto end;
3655 }
3656
3657 sock_recv_len = lttcomm_recv_unix_sock(sock, trigger_buffer.data,
3658 trigger_len);
3659 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
3660 ERR("Failed to receive \"unregister trigger\" command payload");
3661 /* TODO: should this be a new error enum ? */
3662 ret = LTTNG_ERR_INVALID_TRIGGER;
3663 goto end;
3664 }
3665
3666 view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
3667 if (lttng_trigger_create_from_buffer(&view, &trigger) !=
3668 trigger_len) {
3669 ERR("Invalid trigger payload received in \"unregister trigger\" command");
3670 ret = LTTNG_ERR_INVALID_TRIGGER;
3671 goto end;
3672 }
3673
3674 ret = notification_thread_command_unregister_trigger(notification_thread,
3675 trigger);
3676 end:
3677 lttng_trigger_destroy(trigger);
3678 lttng_dynamic_buffer_reset(&trigger_buffer);
3679 return ret;
3680 }
3681
3682 /*
3683 * Send relayd sockets from snapshot output to consumer. Ignore request if the
3684 * snapshot output is *not* set with a remote destination.
3685 *
3686 * Return 0 on success or a LTTNG_ERR code.
3687 */
3688 static int set_relayd_for_snapshot(struct consumer_output *consumer,
3689 struct snapshot_output *snap_output, struct ltt_session *session)
3690 {
3691 int ret = LTTNG_OK;
3692 struct lttng_ht_iter iter;
3693 struct consumer_socket *socket;
3694
3695 assert(consumer);
3696 assert(snap_output);
3697 assert(session);
3698
3699 DBG2("Set relayd object from snapshot output");
3700
3701 /* Ignore if snapshot consumer output is not network. */
3702 if (snap_output->consumer->type != CONSUMER_DST_NET) {
3703 goto error;
3704 }
3705
3706 /*
3707 * For each consumer socket, create and send the relayd object of the
3708 * snapshot output.
3709 */
3710 rcu_read_lock();
3711 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
3712 socket, node.node) {
3713 pthread_mutex_lock(socket->lock);
3714 ret = send_consumer_relayd_sockets(0, session->id,
3715 snap_output->consumer, socket,
3716 session->name, session->hostname,
3717 session->live_timer);
3718 pthread_mutex_unlock(socket->lock);
3719 if (ret != LTTNG_OK) {
3720 rcu_read_unlock();
3721 goto error;
3722 }
3723 }
3724 rcu_read_unlock();
3725
3726 error:
3727 return ret;
3728 }
3729
3730 /*
3731 * Record a kernel snapshot.
3732 *
3733 * Return LTTNG_OK on success or a LTTNG_ERR code.
3734 */
3735 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
3736 struct snapshot_output *output, struct ltt_session *session,
3737 int wait, uint64_t nb_packets_per_stream)
3738 {
3739 int ret;
3740
3741 assert(ksess);
3742 assert(output);
3743 assert(session);
3744
3745
3746 /*
3747 * Copy kernel session sockets so we can communicate with the right
3748 * consumer for the snapshot record command.
3749 */
3750 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
3751 if (ret < 0) {
3752 ret = LTTNG_ERR_NOMEM;
3753 goto error;
3754 }
3755
3756 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
3757 if (ret != LTTNG_OK) {
3758 goto error_snapshot;
3759 }
3760
3761 ret = kernel_snapshot_record(ksess, output, wait, nb_packets_per_stream);
3762 if (ret != LTTNG_OK) {
3763 goto error_snapshot;
3764 }
3765
3766 ret = LTTNG_OK;
3767 goto end;
3768
3769 error_snapshot:
3770 /* Clean up copied sockets so this output can use some other later on. */
3771 consumer_destroy_output_sockets(output->consumer);
3772 error:
3773 end:
3774 return ret;
3775 }
3776
3777 /*
3778 * Record a UST snapshot.
3779 *
3780 * Return 0 on success or a LTTNG_ERR error code.
3781 */
3782 static int record_ust_snapshot(struct ltt_ust_session *usess,
3783 struct snapshot_output *output, struct ltt_session *session,
3784 int wait, uint64_t nb_packets_per_stream)
3785 {
3786 int ret;
3787
3788 assert(usess);
3789 assert(output);
3790 assert(session);
3791
3792 /*
3793 * Copy UST session sockets so we can communicate with the right
3794 * consumer for the snapshot record command.
3795 */
3796 ret = consumer_copy_sockets(output->consumer, usess->consumer);
3797 if (ret < 0) {
3798 ret = LTTNG_ERR_NOMEM;
3799 goto error;
3800 }
3801
3802 ret = set_relayd_for_snapshot(usess->consumer, output, session);
3803 if (ret != LTTNG_OK) {
3804 goto error_snapshot;
3805 }
3806
3807 ret = ust_app_snapshot_record(usess, output, wait, nb_packets_per_stream);
3808 if (ret < 0) {
3809 switch (-ret) {
3810 case EINVAL:
3811 ret = LTTNG_ERR_INVALID;
3812 break;
3813 default:
3814 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3815 break;
3816 }
3817 goto error_snapshot;
3818 }
3819
3820 ret = LTTNG_OK;
3821
3822 error_snapshot:
3823 /* Clean up copied sockets so this output can use some other later on. */
3824 consumer_destroy_output_sockets(output->consumer);
3825 error:
3826 return ret;
3827 }
3828
3829 static
3830 uint64_t get_session_size_one_more_packet_per_stream(struct ltt_session *session,
3831 uint64_t cur_nr_packets)
3832 {
3833 uint64_t tot_size = 0;
3834
3835 if (session->kernel_session) {
3836 struct ltt_kernel_channel *chan;
3837 struct ltt_kernel_session *ksess = session->kernel_session;
3838
3839 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
3840 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
3841 /*
3842 * Don't take channel into account if we
3843 * already grab all its packets.
3844 */
3845 continue;
3846 }
3847 tot_size += chan->channel->attr.subbuf_size
3848 * chan->stream_count;
3849 }
3850 }
3851
3852 if (session->ust_session) {
3853 struct ltt_ust_session *usess = session->ust_session;
3854
3855 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
3856 cur_nr_packets);
3857 }
3858
3859 return tot_size;
3860 }
3861
3862 /*
3863 * Calculate the number of packets we can grab from each stream that
3864 * fits within the overall snapshot max size.
3865 *
3866 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
3867 * the number of packets per stream.
3868 *
3869 * TODO: this approach is not perfect: we consider the worse case
3870 * (packet filling the sub-buffers) as an upper bound, but we could do
3871 * better if we do this calculation while we actually grab the packet
3872 * content: we would know how much padding we don't actually store into
3873 * the file.
3874 *
3875 * This algorithm is currently bounded by the number of packets per
3876 * stream.
3877 *
3878 * Since we call this algorithm before actually grabbing the data, it's
3879 * an approximation: for instance, applications could appear/disappear
3880 * in between this call and actually grabbing data.
3881 */
3882 static
3883 int64_t get_session_nb_packets_per_stream(struct ltt_session *session, uint64_t max_size)
3884 {
3885 int64_t size_left;
3886 uint64_t cur_nb_packets = 0;
3887
3888 if (!max_size) {
3889 return 0; /* Infinite */
3890 }
3891
3892 size_left = max_size;
3893 for (;;) {
3894 uint64_t one_more_packet_tot_size;
3895
3896 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(session,
3897 cur_nb_packets);
3898 if (!one_more_packet_tot_size) {
3899 /* We are already grabbing all packets. */
3900 break;
3901 }
3902 size_left -= one_more_packet_tot_size;
3903 if (size_left < 0) {
3904 break;
3905 }
3906 cur_nb_packets++;
3907 }
3908 if (!cur_nb_packets) {
3909 /* Not enough room to grab one packet of each stream, error. */
3910 return -1;
3911 }
3912 return cur_nb_packets;
3913 }
3914
3915 /*
3916 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
3917 *
3918 * The wait parameter is ignored so this call always wait for the snapshot to
3919 * complete before returning.
3920 *
3921 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3922 */
3923 int cmd_snapshot_record(struct ltt_session *session,
3924 struct lttng_snapshot_output *output, int wait)
3925 {
3926 int ret = LTTNG_OK;
3927 unsigned int use_tmp_output = 0;
3928 struct snapshot_output tmp_output;
3929 unsigned int snapshot_success = 0;
3930 char datetime[16];
3931
3932 assert(session);
3933 assert(output);
3934
3935 DBG("Cmd snapshot record for session %s", session->name);
3936
3937 /* Get the datetime for the snapshot output directory. */
3938 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", datetime,
3939 sizeof(datetime));
3940 if (!ret) {
3941 ret = LTTNG_ERR_INVALID;
3942 goto error;
3943 }
3944
3945 /*
3946 * Permission denied to create an output if the session is not
3947 * set in no output mode.
3948 */
3949 if (session->output_traces) {
3950 ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
3951 goto error;
3952 }
3953
3954 /* The session needs to be started at least once. */
3955 if (!session->has_been_started) {
3956 ret = LTTNG_ERR_START_SESSION_ONCE;
3957 goto error;
3958 }
3959
3960 /* Use temporary output for the session. */
3961 if (*output->ctrl_url != '\0') {
3962 ret = snapshot_output_init(output->max_size, output->name,
3963 output->ctrl_url, output->data_url, session->consumer,
3964 &tmp_output, NULL);
3965 if (ret < 0) {
3966 if (ret == -ENOMEM) {
3967 ret = LTTNG_ERR_NOMEM;
3968 } else {
3969 ret = LTTNG_ERR_INVALID;
3970 }
3971 goto error;
3972 }
3973 /* Use the global session count for the temporary snapshot. */
3974 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3975
3976 /* Use the global datetime */
3977 memcpy(tmp_output.datetime, datetime, sizeof(datetime));
3978 use_tmp_output = 1;
3979 }
3980
3981 if (use_tmp_output) {
3982 int64_t nb_packets_per_stream;
3983
3984 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3985 tmp_output.max_size);
3986 if (nb_packets_per_stream < 0) {
3987 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3988 goto error;
3989 }
3990
3991 if (session->kernel_session) {
3992 ret = record_kernel_snapshot(session->kernel_session,
3993 &tmp_output, session,
3994 wait, nb_packets_per_stream);
3995 if (ret != LTTNG_OK) {
3996 goto error;
3997 }
3998 }
3999
4000 if (session->ust_session) {
4001 ret = record_ust_snapshot(session->ust_session,
4002 &tmp_output, session,
4003 wait, nb_packets_per_stream);
4004 if (ret != LTTNG_OK) {
4005 goto error;
4006 }
4007 }
4008
4009 snapshot_success = 1;
4010 } else {
4011 struct snapshot_output *sout;
4012 struct lttng_ht_iter iter;
4013
4014 rcu_read_lock();
4015 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
4016 &iter.iter, sout, node.node) {
4017 int64_t nb_packets_per_stream;
4018
4019 /*
4020 * Make a local copy of the output and assign the possible
4021 * temporary value given by the caller.
4022 */
4023 memset(&tmp_output, 0, sizeof(tmp_output));
4024 memcpy(&tmp_output, sout, sizeof(tmp_output));
4025
4026 if (output->max_size != (uint64_t) -1ULL) {
4027 tmp_output.max_size = output->max_size;
4028 }
4029
4030 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
4031 tmp_output.max_size);
4032 if (nb_packets_per_stream < 0) {
4033 ret = LTTNG_ERR_MAX_SIZE_INVALID;
4034 rcu_read_unlock();
4035 goto error;
4036 }
4037
4038 /* Use temporary name. */
4039 if (*output->name != '\0') {
4040 if (lttng_strncpy(tmp_output.name, output->name,
4041 sizeof(tmp_output.name))) {
4042 ret = LTTNG_ERR_INVALID;
4043 rcu_read_unlock();
4044 goto error;
4045 }
4046 }
4047
4048 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
4049 memcpy(tmp_output.datetime, datetime, sizeof(datetime));
4050
4051 if (session->kernel_session) {
4052 ret = record_kernel_snapshot(session->kernel_session,
4053 &tmp_output, session,
4054 wait, nb_packets_per_stream);
4055 if (ret != LTTNG_OK) {
4056 rcu_read_unlock();
4057 goto error;
4058 }
4059 }
4060
4061 if (session->ust_session) {
4062 ret = record_ust_snapshot(session->ust_session,
4063 &tmp_output, session,
4064 wait, nb_packets_per_stream);
4065 if (ret != LTTNG_OK) {
4066 rcu_read_unlock();
4067 goto error;
4068 }
4069 }
4070 snapshot_success = 1;
4071 }
4072 rcu_read_unlock();
4073 }
4074
4075 if (snapshot_success) {
4076 session->snapshot.nb_snapshot++;
4077 } else {
4078 ret = LTTNG_ERR_SNAPSHOT_FAIL;
4079 }
4080
4081 error:
4082 return ret;
4083 }
4084
4085 /*
4086 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
4087 */
4088 int cmd_set_session_shm_path(struct ltt_session *session,
4089 const char *shm_path)
4090 {
4091 /* Safety net */
4092 assert(session);
4093
4094 /*
4095 * Can only set shm path before session is started.
4096 */
4097 if (session->has_been_started) {
4098 return LTTNG_ERR_SESSION_STARTED;
4099 }
4100
4101 strncpy(session->shm_path, shm_path,
4102 sizeof(session->shm_path));
4103 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
4104
4105 return 0;
4106 }
4107
4108 /*
4109 * Init command subsystem.
4110 */
4111 void cmd_init(void)
4112 {
4113 /*
4114 * Set network sequence index to 1 for streams to match a relayd
4115 * socket on the consumer side.
4116 */
4117 pthread_mutex_lock(&relayd_net_seq_idx_lock);
4118 relayd_net_seq_idx = 1;
4119 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
4120
4121 DBG("Command subsystem initialized");
4122 }
LTTng 2.0 tools and control repository
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