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Prevent disable event on internal UST events
[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c
1 /*
2 * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License, version 2 only, as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
11 * more details.
12 *
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 51
15 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
16 */
17
18 #define _GNU_SOURCE
19 #define _LGPL_SOURCE
20 #include <assert.h>
21 #include <string.h>
22 #include <inttypes.h>
23 #include <urcu/list.h>
24 #include <urcu/uatomic.h>
25
26 #include <common/defaults.h>
27 #include <common/common.h>
28 #include <common/sessiond-comm/sessiond-comm.h>
29 #include <common/relayd/relayd.h>
30 #include <common/utils.h>
31
32 #include "channel.h"
33 #include "consumer.h"
34 #include "event.h"
35 #include "health-sessiond.h"
36 #include "kernel.h"
37 #include "kernel-consumer.h"
38 #include "lttng-sessiond.h"
39 #include "utils.h"
40 #include "syscall.h"
41
42 #include "cmd.h"
43
44 /*
45 * Used to keep a unique index for each relayd socket created where this value
46 * is associated with streams on the consumer so it can match the right relayd
47 * to send to. It must be accessed with the relayd_net_seq_idx_lock
48 * held.
49 */
50 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
51 static uint64_t relayd_net_seq_idx;
52
53 static int validate_event_name(const char *);
54 static int validate_ust_event_name(const char *);
55 static int cmd_enable_event_internal(struct ltt_session *session,
56 struct lttng_domain *domain,
57 char *channel_name, struct lttng_event *event,
58 char *filter_expression,
59 struct lttng_filter_bytecode *filter,
60 struct lttng_event_exclusion *exclusion,
61 int wpipe);
62
63 /*
64 * Create a session path used by list_lttng_sessions for the case that the
65 * session consumer is on the network.
66 */
67 static int build_network_session_path(char *dst, size_t size,
68 struct ltt_session *session)
69 {
70 int ret, kdata_port, udata_port;
71 struct lttng_uri *kuri = NULL, *uuri = NULL, *uri = NULL;
72 char tmp_uurl[PATH_MAX], tmp_urls[PATH_MAX];
73
74 assert(session);
75 assert(dst);
76
77 memset(tmp_urls, 0, sizeof(tmp_urls));
78 memset(tmp_uurl, 0, sizeof(tmp_uurl));
79
80 kdata_port = udata_port = DEFAULT_NETWORK_DATA_PORT;
81
82 if (session->kernel_session && session->kernel_session->consumer) {
83 kuri = &session->kernel_session->consumer->dst.net.control;
84 kdata_port = session->kernel_session->consumer->dst.net.data.port;
85 }
86
87 if (session->ust_session && session->ust_session->consumer) {
88 uuri = &session->ust_session->consumer->dst.net.control;
89 udata_port = session->ust_session->consumer->dst.net.data.port;
90 }
91
92 if (uuri == NULL && kuri == NULL) {
93 uri = &session->consumer->dst.net.control;
94 kdata_port = session->consumer->dst.net.data.port;
95 } else if (kuri && uuri) {
96 ret = uri_compare(kuri, uuri);
97 if (ret) {
98 /* Not Equal */
99 uri = kuri;
100 /* Build uuri URL string */
101 ret = uri_to_str_url(uuri, tmp_uurl, sizeof(tmp_uurl));
102 if (ret < 0) {
103 goto error;
104 }
105 } else {
106 uri = kuri;
107 }
108 } else if (kuri && uuri == NULL) {
109 uri = kuri;
110 } else if (uuri && kuri == NULL) {
111 uri = uuri;
112 }
113
114 ret = uri_to_str_url(uri, tmp_urls, sizeof(tmp_urls));
115 if (ret < 0) {
116 goto error;
117 }
118
119 /*
120 * Do we have a UST url set. If yes, this means we have both kernel and UST
121 * to print.
122 */
123 if (*tmp_uurl != '\0') {
124 ret = snprintf(dst, size, "[K]: %s [data: %d] -- [U]: %s [data: %d]",
125 tmp_urls, kdata_port, tmp_uurl, udata_port);
126 } else {
127 int dport;
128 if (kuri || (!kuri && !uuri)) {
129 dport = kdata_port;
130 } else {
131 /* No kernel URI, use the UST port. */
132 dport = udata_port;
133 }
134 ret = snprintf(dst, size, "%s [data: %d]", tmp_urls, dport);
135 }
136
137 error:
138 return ret;
139 }
140
141 /*
142 * Fill lttng_channel array of all channels.
143 */
144 static void list_lttng_channels(int domain, struct ltt_session *session,
145 struct lttng_channel *channels)
146 {
147 int i = 0;
148 struct ltt_kernel_channel *kchan;
149
150 DBG("Listing channels for session %s", session->name);
151
152 switch (domain) {
153 case LTTNG_DOMAIN_KERNEL:
154 /* Kernel channels */
155 if (session->kernel_session != NULL) {
156 cds_list_for_each_entry(kchan,
157 &session->kernel_session->channel_list.head, list) {
158 /* Copy lttng_channel struct to array */
159 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
160 channels[i].enabled = kchan->enabled;
161 i++;
162 }
163 }
164 break;
165 case LTTNG_DOMAIN_UST:
166 {
167 struct lttng_ht_iter iter;
168 struct ltt_ust_channel *uchan;
169
170 rcu_read_lock();
171 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
172 &iter.iter, uchan, node.node) {
173 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
174 channels[i].attr.overwrite = uchan->attr.overwrite;
175 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
176 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
177 channels[i].attr.switch_timer_interval =
178 uchan->attr.switch_timer_interval;
179 channels[i].attr.read_timer_interval =
180 uchan->attr.read_timer_interval;
181 channels[i].enabled = uchan->enabled;
182 channels[i].attr.tracefile_size = uchan->tracefile_size;
183 channels[i].attr.tracefile_count = uchan->tracefile_count;
184 switch (uchan->attr.output) {
185 case LTTNG_UST_MMAP:
186 default:
187 channels[i].attr.output = LTTNG_EVENT_MMAP;
188 break;
189 }
190 i++;
191 }
192 rcu_read_unlock();
193 break;
194 }
195 default:
196 break;
197 }
198 }
199
200 /*
201 * Create a list of agent domain events.
202 *
203 * Return number of events in list on success or else a negative value.
204 */
205 static int list_lttng_agent_events(struct agent *agt,
206 struct lttng_event **events)
207 {
208 int i = 0, ret = 0;
209 unsigned int nb_event = 0;
210 struct agent_event *event;
211 struct lttng_event *tmp_events;
212 struct lttng_ht_iter iter;
213
214 assert(agt);
215 assert(events);
216
217 DBG3("Listing agent events");
218
219 rcu_read_lock();
220 nb_event = lttng_ht_get_count(agt->events);
221 rcu_read_unlock();
222 if (nb_event == 0) {
223 ret = nb_event;
224 goto error;
225 }
226
227 tmp_events = zmalloc(nb_event * sizeof(*tmp_events));
228 if (!tmp_events) {
229 PERROR("zmalloc agent events session");
230 ret = -LTTNG_ERR_FATAL;
231 goto error;
232 }
233
234 rcu_read_lock();
235 cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
236 strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
237 tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
238 tmp_events[i].enabled = event->enabled;
239 tmp_events[i].loglevel = event->loglevel;
240 tmp_events[i].loglevel_type = event->loglevel_type;
241 i++;
242 }
243 rcu_read_unlock();
244
245 *events = tmp_events;
246 ret = nb_event;
247
248 error:
249 assert(nb_event == i);
250 return ret;
251 }
252
253 /*
254 * Create a list of ust global domain events.
255 */
256 static int list_lttng_ust_global_events(char *channel_name,
257 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
258 {
259 int i = 0, ret = 0;
260 unsigned int nb_event = 0;
261 struct lttng_ht_iter iter;
262 struct lttng_ht_node_str *node;
263 struct ltt_ust_channel *uchan;
264 struct ltt_ust_event *uevent;
265 struct lttng_event *tmp;
266
267 DBG("Listing UST global events for channel %s", channel_name);
268
269 rcu_read_lock();
270
271 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
272 node = lttng_ht_iter_get_node_str(&iter);
273 if (node == NULL) {
274 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
275 goto error;
276 }
277
278 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
279
280 nb_event = lttng_ht_get_count(uchan->events);
281 if (nb_event == 0) {
282 ret = nb_event;
283 goto error;
284 }
285
286 DBG3("Listing UST global %d events", nb_event);
287
288 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
289 if (tmp == NULL) {
290 ret = LTTNG_ERR_FATAL;
291 goto error;
292 }
293
294 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
295 if (uevent->internal) {
296 /* This event should remain hidden from clients */
297 nb_event--;
298 continue;
299 }
300 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
301 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
302 tmp[i].enabled = uevent->enabled;
303
304 switch (uevent->attr.instrumentation) {
305 case LTTNG_UST_TRACEPOINT:
306 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
307 break;
308 case LTTNG_UST_PROBE:
309 tmp[i].type = LTTNG_EVENT_PROBE;
310 break;
311 case LTTNG_UST_FUNCTION:
312 tmp[i].type = LTTNG_EVENT_FUNCTION;
313 break;
314 }
315
316 tmp[i].loglevel = uevent->attr.loglevel;
317 switch (uevent->attr.loglevel_type) {
318 case LTTNG_UST_LOGLEVEL_ALL:
319 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
320 break;
321 case LTTNG_UST_LOGLEVEL_RANGE:
322 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
323 break;
324 case LTTNG_UST_LOGLEVEL_SINGLE:
325 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
326 break;
327 }
328 if (uevent->filter) {
329 tmp[i].filter = 1;
330 }
331 if (uevent->exclusion) {
332 tmp[i].exclusion = 1;
333 }
334 i++;
335 }
336
337 ret = nb_event;
338 *events = tmp;
339
340 error:
341 rcu_read_unlock();
342 return ret;
343 }
344
345 /*
346 * Fill lttng_event array of all kernel events in the channel.
347 */
348 static int list_lttng_kernel_events(char *channel_name,
349 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
350 {
351 int i = 0, ret;
352 unsigned int nb_event;
353 struct ltt_kernel_event *event;
354 struct ltt_kernel_channel *kchan;
355
356 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
357 if (kchan == NULL) {
358 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
359 goto error;
360 }
361
362 nb_event = kchan->event_count;
363
364 DBG("Listing events for channel %s", kchan->channel->name);
365
366 if (nb_event == 0) {
367 *events = NULL;
368 goto syscall;
369 }
370
371 *events = zmalloc(nb_event * sizeof(struct lttng_event));
372 if (*events == NULL) {
373 ret = LTTNG_ERR_FATAL;
374 goto error;
375 }
376
377 /* Kernel channels */
378 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
379 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
380 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
381 (*events)[i].enabled = event->enabled;
382
383 switch (event->event->instrumentation) {
384 case LTTNG_KERNEL_TRACEPOINT:
385 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
386 break;
387 case LTTNG_KERNEL_KRETPROBE:
388 (*events)[i].type = LTTNG_EVENT_FUNCTION;
389 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
390 sizeof(struct lttng_kernel_kprobe));
391 break;
392 case LTTNG_KERNEL_KPROBE:
393 (*events)[i].type = LTTNG_EVENT_PROBE;
394 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
395 sizeof(struct lttng_kernel_kprobe));
396 break;
397 case LTTNG_KERNEL_FUNCTION:
398 (*events)[i].type = LTTNG_EVENT_FUNCTION;
399 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
400 sizeof(struct lttng_kernel_function));
401 break;
402 case LTTNG_KERNEL_NOOP:
403 (*events)[i].type = LTTNG_EVENT_NOOP;
404 break;
405 case LTTNG_KERNEL_SYSCALL:
406 (*events)[i].type = LTTNG_EVENT_SYSCALL;
407 break;
408 case LTTNG_KERNEL_ALL:
409 assert(0);
410 break;
411 }
412 i++;
413 }
414
415 syscall:
416 if (syscall_table) {
417 ssize_t new_size;
418
419 new_size = syscall_list_channel(kchan, events, nb_event);
420 if (new_size < 0) {
421 free(events);
422 ret = -new_size;
423 goto error;
424 }
425 nb_event = new_size;
426 }
427
428 return nb_event;
429
430 error:
431 /* Negate the error code to differentiate the size from an error */
432 return -ret;
433 }
434
435 /*
436 * Add URI so the consumer output object. Set the correct path depending on the
437 * domain adding the default trace directory.
438 */
439 static int add_uri_to_consumer(struct consumer_output *consumer,
440 struct lttng_uri *uri, int domain, const char *session_name)
441 {
442 int ret = LTTNG_OK;
443 const char *default_trace_dir;
444
445 assert(uri);
446
447 if (consumer == NULL) {
448 DBG("No consumer detected. Don't add URI. Stopping.");
449 ret = LTTNG_ERR_NO_CONSUMER;
450 goto error;
451 }
452
453 switch (domain) {
454 case LTTNG_DOMAIN_KERNEL:
455 default_trace_dir = DEFAULT_KERNEL_TRACE_DIR;
456 break;
457 case LTTNG_DOMAIN_UST:
458 default_trace_dir = DEFAULT_UST_TRACE_DIR;
459 break;
460 default:
461 /*
462 * This case is possible is we try to add the URI to the global tracing
463 * session consumer object which in this case there is no subdir.
464 */
465 default_trace_dir = "";
466 }
467
468 switch (uri->dtype) {
469 case LTTNG_DST_IPV4:
470 case LTTNG_DST_IPV6:
471 DBG2("Setting network URI to consumer");
472
473 if (consumer->type == CONSUMER_DST_NET) {
474 if ((uri->stype == LTTNG_STREAM_CONTROL &&
475 consumer->dst.net.control_isset) ||
476 (uri->stype == LTTNG_STREAM_DATA &&
477 consumer->dst.net.data_isset)) {
478 ret = LTTNG_ERR_URL_EXIST;
479 goto error;
480 }
481 } else {
482 memset(&consumer->dst.net, 0, sizeof(consumer->dst.net));
483 }
484
485 consumer->type = CONSUMER_DST_NET;
486
487 /* Set URI into consumer output object */
488 ret = consumer_set_network_uri(consumer, uri);
489 if (ret < 0) {
490 ret = -ret;
491 goto error;
492 } else if (ret == 1) {
493 /*
494 * URI was the same in the consumer so we do not append the subdir
495 * again so to not duplicate output dir.
496 */
497 ret = LTTNG_OK;
498 goto error;
499 }
500
501 if (uri->stype == LTTNG_STREAM_CONTROL && strlen(uri->subdir) == 0) {
502 ret = consumer_set_subdir(consumer, session_name);
503 if (ret < 0) {
504 ret = LTTNG_ERR_FATAL;
505 goto error;
506 }
507 }
508
509 if (uri->stype == LTTNG_STREAM_CONTROL) {
510 /* On a new subdir, reappend the default trace dir. */
511 strncat(consumer->subdir, default_trace_dir,
512 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
513 DBG3("Append domain trace name to subdir %s", consumer->subdir);
514 }
515
516 break;
517 case LTTNG_DST_PATH:
518 DBG2("Setting trace directory path from URI to %s", uri->dst.path);
519 memset(consumer->dst.trace_path, 0,
520 sizeof(consumer->dst.trace_path));
521 strncpy(consumer->dst.trace_path, uri->dst.path,
522 sizeof(consumer->dst.trace_path));
523 /* Append default trace dir */
524 strncat(consumer->dst.trace_path, default_trace_dir,
525 sizeof(consumer->dst.trace_path) -
526 strlen(consumer->dst.trace_path) - 1);
527 /* Flag consumer as local. */
528 consumer->type = CONSUMER_DST_LOCAL;
529 break;
530 }
531
532 ret = LTTNG_OK;
533
534 error:
535 return ret;
536 }
537
538 /*
539 * Init tracing by creating trace directory and sending fds kernel consumer.
540 */
541 static int init_kernel_tracing(struct ltt_kernel_session *session)
542 {
543 int ret = 0;
544 struct lttng_ht_iter iter;
545 struct consumer_socket *socket;
546
547 assert(session);
548
549 rcu_read_lock();
550
551 if (session->consumer_fds_sent == 0 && session->consumer != NULL) {
552 cds_lfht_for_each_entry(session->consumer->socks->ht, &iter.iter,
553 socket, node.node) {
554 pthread_mutex_lock(socket->lock);
555 ret = kernel_consumer_send_session(socket, session);
556 pthread_mutex_unlock(socket->lock);
557 if (ret < 0) {
558 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
559 goto error;
560 }
561 }
562 }
563
564 error:
565 rcu_read_unlock();
566 return ret;
567 }
568
569 /*
570 * Create a socket to the relayd using the URI.
571 *
572 * On success, the relayd_sock pointer is set to the created socket.
573 * Else, it's stays untouched and a lttcomm error code is returned.
574 */
575 static int create_connect_relayd(struct lttng_uri *uri,
576 struct lttcomm_relayd_sock **relayd_sock)
577 {
578 int ret;
579 struct lttcomm_relayd_sock *rsock;
580
581 rsock = lttcomm_alloc_relayd_sock(uri, RELAYD_VERSION_COMM_MAJOR,
582 RELAYD_VERSION_COMM_MINOR);
583 if (!rsock) {
584 ret = LTTNG_ERR_FATAL;
585 goto error;
586 }
587
588 /*
589 * Connect to relayd so we can proceed with a session creation. This call
590 * can possibly block for an arbitrary amount of time to set the health
591 * state to be in poll execution.
592 */
593 health_poll_entry();
594 ret = relayd_connect(rsock);
595 health_poll_exit();
596 if (ret < 0) {
597 ERR("Unable to reach lttng-relayd");
598 ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
599 goto free_sock;
600 }
601
602 /* Create socket for control stream. */
603 if (uri->stype == LTTNG_STREAM_CONTROL) {
604 DBG3("Creating relayd stream socket from URI");
605
606 /* Check relayd version */
607 ret = relayd_version_check(rsock);
608 if (ret < 0) {
609 ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
610 goto close_sock;
611 }
612 } else if (uri->stype == LTTNG_STREAM_DATA) {
613 DBG3("Creating relayd data socket from URI");
614 } else {
615 /* Command is not valid */
616 ERR("Relayd invalid stream type: %d", uri->stype);
617 ret = LTTNG_ERR_INVALID;
618 goto close_sock;
619 }
620
621 *relayd_sock = rsock;
622
623 return LTTNG_OK;
624
625 close_sock:
626 /* The returned value is not useful since we are on an error path. */
627 (void) relayd_close(rsock);
628 free_sock:
629 free(rsock);
630 error:
631 return ret;
632 }
633
634 /*
635 * Connect to the relayd using URI and send the socket to the right consumer.
636 */
637 static int send_consumer_relayd_socket(int domain, unsigned int session_id,
638 struct lttng_uri *relayd_uri, struct consumer_output *consumer,
639 struct consumer_socket *consumer_sock,
640 char *session_name, char *hostname, int session_live_timer)
641 {
642 int ret;
643 struct lttcomm_relayd_sock *rsock = NULL;
644
645 /* Connect to relayd and make version check if uri is the control. */
646 ret = create_connect_relayd(relayd_uri, &rsock);
647 if (ret != LTTNG_OK) {
648 goto error;
649 }
650 assert(rsock);
651
652 /* Set the network sequence index if not set. */
653 if (consumer->net_seq_index == (uint64_t) -1ULL) {
654 pthread_mutex_lock(&relayd_net_seq_idx_lock);
655 /*
656 * Increment net_seq_idx because we are about to transfer the
657 * new relayd socket to the consumer.
658 * Assign unique key so the consumer can match streams.
659 */
660 consumer->net_seq_index = ++relayd_net_seq_idx;
661 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
662 }
663
664 /* Send relayd socket to consumer. */
665 ret = consumer_send_relayd_socket(consumer_sock, rsock, consumer,
666 relayd_uri->stype, session_id,
667 session_name, hostname, session_live_timer);
668 if (ret < 0) {
669 ret = LTTNG_ERR_ENABLE_CONSUMER_FAIL;
670 goto close_sock;
671 }
672
673 /* Flag that the corresponding socket was sent. */
674 if (relayd_uri->stype == LTTNG_STREAM_CONTROL) {
675 consumer_sock->control_sock_sent = 1;
676 } else if (relayd_uri->stype == LTTNG_STREAM_DATA) {
677 consumer_sock->data_sock_sent = 1;
678 }
679
680 ret = LTTNG_OK;
681
682 /*
683 * Close socket which was dup on the consumer side. The session daemon does
684 * NOT keep track of the relayd socket(s) once transfer to the consumer.
685 */
686
687 close_sock:
688 (void) relayd_close(rsock);
689 free(rsock);
690
691 error:
692 if (ret != LTTNG_OK) {
693 /*
694 * The consumer output for this session should not be used anymore
695 * since the relayd connection failed thus making any tracing or/and
696 * streaming not usable.
697 */
698 consumer->enabled = 0;
699 }
700 return ret;
701 }
702
703 /*
704 * Send both relayd sockets to a specific consumer and domain. This is a
705 * helper function to facilitate sending the information to the consumer for a
706 * session.
707 */
708 static int send_consumer_relayd_sockets(int domain, unsigned int session_id,
709 struct consumer_output *consumer, struct consumer_socket *sock,
710 char *session_name, char *hostname, int session_live_timer)
711 {
712 int ret = LTTNG_OK;
713
714 assert(consumer);
715 assert(sock);
716
717 /* Sending control relayd socket. */
718 if (!sock->control_sock_sent) {
719 ret = send_consumer_relayd_socket(domain, session_id,
720 &consumer->dst.net.control, consumer, sock,
721 session_name, hostname, session_live_timer);
722 if (ret != LTTNG_OK) {
723 goto error;
724 }
725 }
726
727 /* Sending data relayd socket. */
728 if (!sock->data_sock_sent) {
729 ret = send_consumer_relayd_socket(domain, session_id,
730 &consumer->dst.net.data, consumer, sock,
731 session_name, hostname, session_live_timer);
732 if (ret != LTTNG_OK) {
733 goto error;
734 }
735 }
736
737 error:
738 return ret;
739 }
740
741 /*
742 * Setup relayd connections for a tracing session. First creates the socket to
743 * the relayd and send them to the right domain consumer. Consumer type MUST be
744 * network.
745 */
746 int cmd_setup_relayd(struct ltt_session *session)
747 {
748 int ret = LTTNG_OK;
749 struct ltt_ust_session *usess;
750 struct ltt_kernel_session *ksess;
751 struct consumer_socket *socket;
752 struct lttng_ht_iter iter;
753
754 assert(session);
755
756 usess = session->ust_session;
757 ksess = session->kernel_session;
758
759 DBG("Setting relayd for session %s", session->name);
760
761 rcu_read_lock();
762
763 if (usess && usess->consumer && usess->consumer->type == CONSUMER_DST_NET
764 && usess->consumer->enabled) {
765 /* For each consumer socket, send relayd sockets */
766 cds_lfht_for_each_entry(usess->consumer->socks->ht, &iter.iter,
767 socket, node.node) {
768 pthread_mutex_lock(socket->lock);
769 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_UST, session->id,
770 usess->consumer, socket,
771 session->name, session->hostname,
772 session->live_timer);
773 pthread_mutex_unlock(socket->lock);
774 if (ret != LTTNG_OK) {
775 goto error;
776 }
777 /* Session is now ready for network streaming. */
778 session->net_handle = 1;
779 }
780 }
781
782 if (ksess && ksess->consumer && ksess->consumer->type == CONSUMER_DST_NET
783 && ksess->consumer->enabled) {
784 cds_lfht_for_each_entry(ksess->consumer->socks->ht, &iter.iter,
785 socket, node.node) {
786 pthread_mutex_lock(socket->lock);
787 ret = send_consumer_relayd_sockets(LTTNG_DOMAIN_KERNEL, session->id,
788 ksess->consumer, socket,
789 session->name, session->hostname,
790 session->live_timer);
791 pthread_mutex_unlock(socket->lock);
792 if (ret != LTTNG_OK) {
793 goto error;
794 }
795 /* Session is now ready for network streaming. */
796 session->net_handle = 1;
797 }
798 }
799
800 error:
801 rcu_read_unlock();
802 return ret;
803 }
804
805 /*
806 * Start a kernel session by opening all necessary streams.
807 */
808 static int start_kernel_session(struct ltt_kernel_session *ksess, int wpipe)
809 {
810 int ret;
811 struct ltt_kernel_channel *kchan;
812
813 /* Open kernel metadata */
814 if (ksess->metadata == NULL && ksess->output_traces) {
815 ret = kernel_open_metadata(ksess);
816 if (ret < 0) {
817 ret = LTTNG_ERR_KERN_META_FAIL;
818 goto error;
819 }
820 }
821
822 /* Open kernel metadata stream */
823 if (ksess->metadata && ksess->metadata_stream_fd < 0) {
824 ret = kernel_open_metadata_stream(ksess);
825 if (ret < 0) {
826 ERR("Kernel create metadata stream failed");
827 ret = LTTNG_ERR_KERN_STREAM_FAIL;
828 goto error;
829 }
830 }
831
832 /* For each channel */
833 cds_list_for_each_entry(kchan, &ksess->channel_list.head, list) {
834 if (kchan->stream_count == 0) {
835 ret = kernel_open_channel_stream(kchan);
836 if (ret < 0) {
837 ret = LTTNG_ERR_KERN_STREAM_FAIL;
838 goto error;
839 }
840 /* Update the stream global counter */
841 ksess->stream_count_global += ret;
842 }
843 }
844
845 /* Setup kernel consumer socket and send fds to it */
846 ret = init_kernel_tracing(ksess);
847 if (ret != 0) {
848 ret = LTTNG_ERR_KERN_START_FAIL;
849 goto error;
850 }
851
852 /* This start the kernel tracing */
853 ret = kernel_start_session(ksess);
854 if (ret < 0) {
855 ret = LTTNG_ERR_KERN_START_FAIL;
856 goto error;
857 }
858
859 /* Quiescent wait after starting trace */
860 kernel_wait_quiescent(kernel_tracer_fd);
861
862 ksess->active = 1;
863
864 ret = LTTNG_OK;
865
866 error:
867 return ret;
868 }
869
870 /*
871 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
872 */
873 int cmd_disable_channel(struct ltt_session *session, int domain,
874 char *channel_name)
875 {
876 int ret;
877 struct ltt_ust_session *usess;
878
879 usess = session->ust_session;
880
881 rcu_read_lock();
882
883 switch (domain) {
884 case LTTNG_DOMAIN_KERNEL:
885 {
886 ret = channel_kernel_disable(session->kernel_session,
887 channel_name);
888 if (ret != LTTNG_OK) {
889 goto error;
890 }
891
892 kernel_wait_quiescent(kernel_tracer_fd);
893 break;
894 }
895 case LTTNG_DOMAIN_UST:
896 {
897 struct ltt_ust_channel *uchan;
898 struct lttng_ht *chan_ht;
899
900 chan_ht = usess->domain_global.channels;
901
902 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
903 if (uchan == NULL) {
904 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
905 goto error;
906 }
907
908 ret = channel_ust_disable(usess, uchan);
909 if (ret != LTTNG_OK) {
910 goto error;
911 }
912 break;
913 }
914 default:
915 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
916 goto error;
917 }
918
919 ret = LTTNG_OK;
920
921 error:
922 rcu_read_unlock();
923 return ret;
924 }
925
926 /*
927 * Command LTTNG_TRACK_PID processed by the client thread.
928 *
929 * Called with session lock held.
930 */
931 int cmd_track_pid(struct ltt_session *session, int domain, int pid)
932 {
933 int ret;
934
935 rcu_read_lock();
936
937 switch (domain) {
938 case LTTNG_DOMAIN_KERNEL:
939 {
940 struct ltt_kernel_session *ksess;
941
942 ksess = session->kernel_session;
943
944 ret = kernel_track_pid(ksess, pid);
945 if (ret != LTTNG_OK) {
946 goto error;
947 }
948
949 kernel_wait_quiescent(kernel_tracer_fd);
950 break;
951 }
952 case LTTNG_DOMAIN_UST:
953 {
954 struct ltt_ust_session *usess;
955
956 usess = session->ust_session;
957
958 ret = trace_ust_track_pid(usess, pid);
959 if (ret != LTTNG_OK) {
960 goto error;
961 }
962 break;
963 }
964 default:
965 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
966 goto error;
967 }
968
969 ret = LTTNG_OK;
970
971 error:
972 rcu_read_unlock();
973 return ret;
974 }
975
976 /*
977 * Command LTTNG_UNTRACK_PID processed by the client thread.
978 *
979 * Called with session lock held.
980 */
981 int cmd_untrack_pid(struct ltt_session *session, int domain, int pid)
982 {
983 int ret;
984
985 rcu_read_lock();
986
987 switch (domain) {
988 case LTTNG_DOMAIN_KERNEL:
989 {
990 struct ltt_kernel_session *ksess;
991
992 ksess = session->kernel_session;
993
994 ret = kernel_untrack_pid(ksess, pid);
995 if (ret != LTTNG_OK) {
996 goto error;
997 }
998
999 kernel_wait_quiescent(kernel_tracer_fd);
1000 break;
1001 }
1002 case LTTNG_DOMAIN_UST:
1003 {
1004 struct ltt_ust_session *usess;
1005
1006 usess = session->ust_session;
1007
1008 ret = trace_ust_untrack_pid(usess, pid);
1009 if (ret != LTTNG_OK) {
1010 goto error;
1011 }
1012 break;
1013 }
1014 default:
1015 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1016 goto error;
1017 }
1018
1019 ret = LTTNG_OK;
1020
1021 error:
1022 rcu_read_unlock();
1023 return ret;
1024 }
1025
1026 /*
1027 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1028 *
1029 * The wpipe arguments is used as a notifier for the kernel thread.
1030 */
1031 int cmd_enable_channel(struct ltt_session *session,
1032 struct lttng_domain *domain, struct lttng_channel *attr, int wpipe)
1033 {
1034 int ret;
1035 struct ltt_ust_session *usess = session->ust_session;
1036 struct lttng_ht *chan_ht;
1037 size_t len;
1038
1039 assert(session);
1040 assert(attr);
1041 assert(domain);
1042
1043 len = strnlen(attr->name, sizeof(attr->name));
1044
1045 /* Validate channel name */
1046 if (attr->name[0] == '.' ||
1047 memchr(attr->name, '/', len) != NULL) {
1048 ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
1049 goto end;
1050 }
1051
1052 DBG("Enabling channel %s for session %s", attr->name, session->name);
1053
1054 rcu_read_lock();
1055
1056 /*
1057 * Don't try to enable a channel if the session has been started at
1058 * some point in time before. The tracer does not allow it.
1059 */
1060 if (session->has_been_started) {
1061 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1062 goto error;
1063 }
1064
1065 /*
1066 * If the session is a live session, remove the switch timer, the
1067 * live timer does the same thing but sends also synchronisation
1068 * beacons for inactive streams.
1069 */
1070 if (session->live_timer > 0) {
1071 attr->attr.live_timer_interval = session->live_timer;
1072 attr->attr.switch_timer_interval = 0;
1073 }
1074
1075 /*
1076 * The ringbuffer (both in user space and kernel) behave badly in overwrite
1077 * mode and with less than 2 subbuf so block it right away and send back an
1078 * invalid attribute error.
1079 */
1080 if (attr->attr.overwrite && attr->attr.num_subbuf < 2) {
1081 ret = LTTNG_ERR_INVALID;
1082 goto error;
1083 }
1084
1085 switch (domain->type) {
1086 case LTTNG_DOMAIN_KERNEL:
1087 {
1088 struct ltt_kernel_channel *kchan;
1089
1090 kchan = trace_kernel_get_channel_by_name(attr->name,
1091 session->kernel_session);
1092 if (kchan == NULL) {
1093 ret = channel_kernel_create(session->kernel_session, attr, wpipe);
1094 if (attr->name[0] != '\0') {
1095 session->kernel_session->has_non_default_channel = 1;
1096 }
1097 } else {
1098 ret = channel_kernel_enable(session->kernel_session, kchan);
1099 }
1100
1101 if (ret != LTTNG_OK) {
1102 goto error;
1103 }
1104
1105 kernel_wait_quiescent(kernel_tracer_fd);
1106 break;
1107 }
1108 case LTTNG_DOMAIN_UST:
1109 {
1110 struct ltt_ust_channel *uchan;
1111
1112 chan_ht = usess->domain_global.channels;
1113
1114 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
1115 if (uchan == NULL) {
1116 ret = channel_ust_create(usess, attr, domain->buf_type);
1117 if (attr->name[0] != '\0') {
1118 usess->has_non_default_channel = 1;
1119 }
1120 } else {
1121 ret = channel_ust_enable(usess, uchan);
1122 }
1123 break;
1124 }
1125 default:
1126 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1127 goto error;
1128 }
1129
1130 error:
1131 rcu_read_unlock();
1132 end:
1133 return ret;
1134 }
1135
1136 /*
1137 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1138 */
1139 int cmd_disable_event(struct ltt_session *session, int domain,
1140 char *channel_name,
1141 struct lttng_event *event)
1142 {
1143 int ret;
1144 char *event_name;
1145
1146 DBG("Disable event command for event \'%s\'", event->name);
1147
1148 event_name = event->name;
1149 if (validate_event_name(event_name)) {
1150 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1151 goto error;
1152 }
1153
1154 /* Error out on unhandled search criteria */
1155 if (event->loglevel_type || event->loglevel != -1 || event->enabled
1156 || event->pid || event->filter || event->exclusion) {
1157 ret = LTTNG_ERR_UNK;
1158 goto error;
1159 }
1160
1161 rcu_read_lock();
1162
1163 switch (domain) {
1164 case LTTNG_DOMAIN_KERNEL:
1165 {
1166 struct ltt_kernel_channel *kchan;
1167 struct ltt_kernel_session *ksess;
1168
1169 ksess = session->kernel_session;
1170
1171 /*
1172 * If a non-default channel has been created in the
1173 * session, explicitely require that -c chan_name needs
1174 * to be provided.
1175 */
1176 if (ksess->has_non_default_channel && channel_name[0] == '\0') {
1177 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1178 goto error_unlock;
1179 }
1180
1181 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
1182 if (kchan == NULL) {
1183 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
1184 goto error_unlock;
1185 }
1186
1187 switch (event->type) {
1188 case LTTNG_EVENT_ALL:
1189 ret = event_kernel_disable_event_all(kchan);
1190 if (ret != LTTNG_OK) {
1191 goto error_unlock;
1192 }
1193 break;
1194 case LTTNG_EVENT_TRACEPOINT: /* fall-through */
1195 case LTTNG_EVENT_SYSCALL:
1196 if (!strcmp(event_name, "*")) {
1197 ret = event_kernel_disable_event_type(kchan,
1198 event->type);
1199 } else {
1200 ret = event_kernel_disable_event(kchan,
1201 event_name);
1202 }
1203 if (ret != LTTNG_OK) {
1204 goto error_unlock;
1205 }
1206 break;
1207 case LTTNG_EVENT_PROBE:
1208 case LTTNG_EVENT_FUNCTION:
1209 case LTTNG_EVENT_FUNCTION_ENTRY:
1210 ret = event_kernel_disable_event(kchan, event_name);
1211 if (ret != LTTNG_OK) {
1212 goto error_unlock;
1213 }
1214 break;
1215 default:
1216 ret = LTTNG_ERR_UNK;
1217 goto error_unlock;
1218 }
1219
1220 kernel_wait_quiescent(kernel_tracer_fd);
1221 break;
1222 }
1223 case LTTNG_DOMAIN_UST:
1224 {
1225 struct ltt_ust_channel *uchan;
1226 struct ltt_ust_session *usess;
1227
1228 usess = session->ust_session;
1229
1230 if (validate_ust_event_name(event_name)) {
1231 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1232 goto error_unlock;
1233 }
1234
1235 /*
1236 * If a non-default channel has been created in the
1237 * session, explicitely require that -c chan_name needs
1238 * to be provided.
1239 */
1240 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1241 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1242 goto error_unlock;
1243 }
1244
1245 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1246 channel_name);
1247 if (uchan == NULL) {
1248 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
1249 goto error_unlock;
1250 }
1251
1252 switch (event->type) {
1253 case LTTNG_EVENT_ALL:
1254 ret = event_ust_disable_tracepoint(usess, uchan, event_name);
1255 if (ret != LTTNG_OK) {
1256 goto error_unlock;
1257 }
1258 break;
1259 default:
1260 ret = LTTNG_ERR_UNK;
1261 goto error_unlock;
1262 }
1263
1264 DBG3("Disable UST event %s in channel %s completed", event_name,
1265 channel_name);
1266 break;
1267 }
1268 case LTTNG_DOMAIN_LOG4J:
1269 case LTTNG_DOMAIN_JUL:
1270 case LTTNG_DOMAIN_PYTHON:
1271 {
1272 struct agent *agt;
1273 struct ltt_ust_session *usess = session->ust_session;
1274
1275 assert(usess);
1276
1277 switch (event->type) {
1278 case LTTNG_EVENT_ALL:
1279 break;
1280 default:
1281 ret = LTTNG_ERR_UNK;
1282 goto error_unlock;
1283 }
1284
1285 agt = trace_ust_find_agent(usess, domain);
1286 if (!agt) {
1287 ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
1288 goto error_unlock;
1289 }
1290 /* The wild card * means that everything should be disabled. */
1291 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1292 ret = event_agent_disable_all(usess, agt);
1293 } else {
1294 ret = event_agent_disable(usess, agt, event_name);
1295 }
1296 if (ret != LTTNG_OK) {
1297 goto error_unlock;
1298 }
1299
1300 break;
1301 }
1302 default:
1303 ret = LTTNG_ERR_UND;
1304 goto error_unlock;
1305 }
1306
1307 ret = LTTNG_OK;
1308
1309 error_unlock:
1310 rcu_read_unlock();
1311 error:
1312 return ret;
1313 }
1314
1315 /*
1316 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1317 */
1318 int cmd_add_context(struct ltt_session *session, int domain,
1319 char *channel_name, struct lttng_event_context *ctx, int kwpipe)
1320 {
1321 int ret, chan_kern_created = 0, chan_ust_created = 0;
1322
1323 switch (domain) {
1324 case LTTNG_DOMAIN_KERNEL:
1325 assert(session->kernel_session);
1326
1327 if (session->kernel_session->channel_count == 0) {
1328 /* Create default channel */
1329 ret = channel_kernel_create(session->kernel_session, NULL, kwpipe);
1330 if (ret != LTTNG_OK) {
1331 goto error;
1332 }
1333 chan_kern_created = 1;
1334 }
1335 /* Add kernel context to kernel tracer */
1336 ret = context_kernel_add(session->kernel_session, ctx, channel_name);
1337 if (ret != LTTNG_OK) {
1338 goto error;
1339 }
1340 break;
1341 case LTTNG_DOMAIN_UST:
1342 {
1343 struct ltt_ust_session *usess = session->ust_session;
1344 unsigned int chan_count;
1345
1346 assert(usess);
1347
1348 chan_count = lttng_ht_get_count(usess->domain_global.channels);
1349 if (chan_count == 0) {
1350 struct lttng_channel *attr;
1351 /* Create default channel */
1352 attr = channel_new_default_attr(domain, usess->buffer_type);
1353 if (attr == NULL) {
1354 ret = LTTNG_ERR_FATAL;
1355 goto error;
1356 }
1357
1358 ret = channel_ust_create(usess, attr, usess->buffer_type);
1359 if (ret != LTTNG_OK) {
1360 free(attr);
1361 goto error;
1362 }
1363 free(attr);
1364 chan_ust_created = 1;
1365 }
1366
1367 ret = context_ust_add(usess, domain, ctx, channel_name);
1368 if (ret != LTTNG_OK) {
1369 goto error;
1370 }
1371 break;
1372 }
1373 default:
1374 ret = LTTNG_ERR_UND;
1375 goto error;
1376 }
1377
1378 return LTTNG_OK;
1379
1380 error:
1381 if (chan_kern_created) {
1382 struct ltt_kernel_channel *kchan =
1383 trace_kernel_get_channel_by_name(DEFAULT_CHANNEL_NAME,
1384 session->kernel_session);
1385 /* Created previously, this should NOT fail. */
1386 assert(kchan);
1387 kernel_destroy_channel(kchan);
1388 }
1389
1390 if (chan_ust_created) {
1391 struct ltt_ust_channel *uchan =
1392 trace_ust_find_channel_by_name(
1393 session->ust_session->domain_global.channels,
1394 DEFAULT_CHANNEL_NAME);
1395 /* Created previously, this should NOT fail. */
1396 assert(uchan);
1397 /* Remove from the channel list of the session. */
1398 trace_ust_delete_channel(session->ust_session->domain_global.channels,
1399 uchan);
1400 trace_ust_destroy_channel(uchan);
1401 }
1402 return ret;
1403 }
1404
1405 static int validate_event_name(const char *name)
1406 {
1407 int ret = 0;
1408 const char *c = name;
1409 const char *event_name_end = c + LTTNG_SYMBOL_NAME_LEN;
1410
1411 /*
1412 * Make sure that unescaped wildcards are only used as the last
1413 * character of the event name.
1414 */
1415 while (c < event_name_end) {
1416 switch (*c) {
1417 case '\0':
1418 goto end;
1419 case '\\':
1420 c++;
1421 break;
1422 case '*':
1423 if ((c + 1) < event_name_end && *(c + 1)) {
1424 /* Wildcard is not the last character */
1425 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1426 goto end;
1427 }
1428 default:
1429 break;
1430 }
1431 c++;
1432 }
1433 end:
1434 return ret;
1435 }
1436
1437 static inline bool name_starts_with(const char *name, const char *prefix)
1438 {
1439 const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
1440
1441 return !strncmp(name, prefix, max_cmp_len);
1442 }
1443
1444 /* Perform userspace-specific event name validation */
1445 static int validate_ust_event_name(const char *name)
1446 {
1447 int ret = 0;
1448
1449 if (!name) {
1450 ret = -1;
1451 goto end;
1452 }
1453
1454 /*
1455 * Check name against all internal UST event component namespaces used
1456 * by the agents.
1457 */
1458 if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
1459 name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
1460 name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
1461 ret = -1;
1462 }
1463
1464 end:
1465 return ret;
1466 }
1467
1468 /*
1469 * Internal version of cmd_enable_event() with a supplemental
1470 * "internal_event" flag which is used to enable internal events which should
1471 * be hidden from clients. Such events are used in the agent implementation to
1472 * enable the events through which all "agent" events are funeled.
1473 */
1474 static int _cmd_enable_event(struct ltt_session *session,
1475 struct lttng_domain *domain,
1476 char *channel_name, struct lttng_event *event,
1477 char *filter_expression,
1478 struct lttng_filter_bytecode *filter,
1479 struct lttng_event_exclusion *exclusion,
1480 int wpipe, bool internal_event)
1481 {
1482 int ret, channel_created = 0;
1483 struct lttng_channel *attr;
1484
1485 assert(session);
1486 assert(event);
1487 assert(channel_name);
1488
1489 DBG("Enable event command for event \'%s\'", event->name);
1490
1491 ret = validate_event_name(event->name);
1492 if (ret) {
1493 goto error;
1494 }
1495
1496 rcu_read_lock();
1497
1498 switch (domain->type) {
1499 case LTTNG_DOMAIN_KERNEL:
1500 {
1501 struct ltt_kernel_channel *kchan;
1502
1503 /*
1504 * If a non-default channel has been created in the
1505 * session, explicitely require that -c chan_name needs
1506 * to be provided.
1507 */
1508 if (session->kernel_session->has_non_default_channel
1509 && channel_name[0] == '\0') {
1510 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1511 goto error;
1512 }
1513
1514 kchan = trace_kernel_get_channel_by_name(channel_name,
1515 session->kernel_session);
1516 if (kchan == NULL) {
1517 attr = channel_new_default_attr(LTTNG_DOMAIN_KERNEL,
1518 LTTNG_BUFFER_GLOBAL);
1519 if (attr == NULL) {
1520 ret = LTTNG_ERR_FATAL;
1521 goto error;
1522 }
1523 strncpy(attr->name, channel_name, sizeof(attr->name));
1524
1525 ret = cmd_enable_channel(session, domain, attr, wpipe);
1526 if (ret != LTTNG_OK) {
1527 free(attr);
1528 goto error;
1529 }
1530 free(attr);
1531
1532 channel_created = 1;
1533 }
1534
1535 /* Get the newly created kernel channel pointer */
1536 kchan = trace_kernel_get_channel_by_name(channel_name,
1537 session->kernel_session);
1538 if (kchan == NULL) {
1539 /* This sould not happen... */
1540 ret = LTTNG_ERR_FATAL;
1541 goto error;
1542 }
1543
1544 switch (event->type) {
1545 case LTTNG_EVENT_ALL:
1546 {
1547 char *filter_expression_a = NULL;
1548 struct lttng_filter_bytecode *filter_a = NULL;
1549
1550 /*
1551 * We need to duplicate filter_expression and filter,
1552 * because ownership is passed to first enable
1553 * event.
1554 */
1555 if (filter_expression) {
1556 filter_expression_a = strdup(filter_expression);
1557 if (!filter_expression_a) {
1558 ret = LTTNG_ERR_FATAL;
1559 goto error;
1560 }
1561 }
1562 if (filter) {
1563 filter_a = zmalloc(sizeof(*filter_a) + filter->len);
1564 if (!filter_a) {
1565 free(filter_expression_a);
1566 ret = LTTNG_ERR_FATAL;
1567 goto error;
1568 }
1569 memcpy(filter_a, filter, sizeof(*filter_a) + filter->len);
1570 }
1571 event->type = LTTNG_EVENT_TRACEPOINT; /* Hack */
1572 ret = event_kernel_enable_event(kchan, event,
1573 filter_expression, filter);
1574 /* We have passed ownership */
1575 filter_expression = NULL;
1576 filter = NULL;
1577 if (ret != LTTNG_OK) {
1578 if (channel_created) {
1579 /* Let's not leak a useless channel. */
1580 kernel_destroy_channel(kchan);
1581 }
1582 free(filter_expression_a);
1583 free(filter_a);
1584 goto error;
1585 }
1586 event->type = LTTNG_EVENT_SYSCALL; /* Hack */
1587 ret = event_kernel_enable_event(kchan, event,
1588 filter_expression_a, filter_a);
1589 if (ret != LTTNG_OK) {
1590 free(filter_expression_a);
1591 free(filter_a);
1592 goto error;
1593 }
1594 break;
1595 }
1596 case LTTNG_EVENT_PROBE:
1597 case LTTNG_EVENT_FUNCTION:
1598 case LTTNG_EVENT_FUNCTION_ENTRY:
1599 case LTTNG_EVENT_TRACEPOINT:
1600 ret = event_kernel_enable_event(kchan, event,
1601 filter_expression, filter);
1602 /* We have passed ownership */
1603 filter_expression = NULL;
1604 filter = NULL;
1605 if (ret != LTTNG_OK) {
1606 if (channel_created) {
1607 /* Let's not leak a useless channel. */
1608 kernel_destroy_channel(kchan);
1609 }
1610 goto error;
1611 }
1612 break;
1613 case LTTNG_EVENT_SYSCALL:
1614 ret = event_kernel_enable_event(kchan, event,
1615 filter_expression, filter);
1616 /* We have passed ownership */
1617 filter_expression = NULL;
1618 filter = NULL;
1619 if (ret != LTTNG_OK) {
1620 goto error;
1621 }
1622 break;
1623 default:
1624 ret = LTTNG_ERR_UNK;
1625 goto error;
1626 }
1627
1628 kernel_wait_quiescent(kernel_tracer_fd);
1629 break;
1630 }
1631 case LTTNG_DOMAIN_UST:
1632 {
1633 struct ltt_ust_channel *uchan;
1634 struct ltt_ust_session *usess = session->ust_session;
1635
1636 assert(usess);
1637
1638 /*
1639 * If a non-default channel has been created in the
1640 * session, explicitely require that -c chan_name needs
1641 * to be provided.
1642 */
1643 if (usess->has_non_default_channel && channel_name[0] == '\0') {
1644 ret = LTTNG_ERR_NEED_CHANNEL_NAME;
1645 goto error;
1646 }
1647
1648 /* Get channel from global UST domain */
1649 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1650 channel_name);
1651 if (uchan == NULL) {
1652 /* Create default channel */
1653 attr = channel_new_default_attr(LTTNG_DOMAIN_UST,
1654 usess->buffer_type);
1655 if (attr == NULL) {
1656 ret = LTTNG_ERR_FATAL;
1657 goto error;
1658 }
1659 strncpy(attr->name, channel_name, sizeof(attr->name));
1660
1661 ret = cmd_enable_channel(session, domain, attr, wpipe);
1662 if (ret != LTTNG_OK) {
1663 free(attr);
1664 goto error;
1665 }
1666 free(attr);
1667
1668 /* Get the newly created channel reference back */
1669 uchan = trace_ust_find_channel_by_name(
1670 usess->domain_global.channels, channel_name);
1671 assert(uchan);
1672 }
1673
1674 if (!internal_event) {
1675 /*
1676 * Ensure the event name is not reserved for internal
1677 * use.
1678 */
1679 ret = validate_ust_event_name(event->name);
1680 if (ret) {
1681 WARN("Userspace event name %s failed validation.",
1682 event->name ?
1683 event->name : "NULL");
1684 ret = LTTNG_ERR_INVALID_EVENT_NAME;
1685 goto error;
1686 }
1687 }
1688
1689 /* At this point, the session and channel exist on the tracer */
1690 ret = event_ust_enable_tracepoint(usess, uchan, event,
1691 filter_expression, filter, exclusion,
1692 internal_event);
1693 /* We have passed ownership */
1694 filter_expression = NULL;
1695 filter = NULL;
1696 exclusion = NULL;
1697 if (ret != LTTNG_OK) {
1698 goto error;
1699 }
1700 break;
1701 }
1702 case LTTNG_DOMAIN_LOG4J:
1703 case LTTNG_DOMAIN_JUL:
1704 case LTTNG_DOMAIN_PYTHON:
1705 {
1706 const char *default_event_name, *default_chan_name;
1707 struct agent *agt;
1708 struct lttng_event uevent;
1709 struct lttng_domain tmp_dom;
1710 struct ltt_ust_session *usess = session->ust_session;
1711
1712 assert(usess);
1713
1714 agt = trace_ust_find_agent(usess, domain->type);
1715 if (!agt) {
1716 agt = agent_create(domain->type);
1717 if (!agt) {
1718 ret = -LTTNG_ERR_NOMEM;
1719 goto error;
1720 }
1721 agent_add(agt, usess->agents);
1722 }
1723
1724 /* Create the default tracepoint. */
1725 memset(&uevent, 0, sizeof(uevent));
1726 uevent.type = LTTNG_EVENT_TRACEPOINT;
1727 uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
1728 default_event_name = event_get_default_agent_ust_name(domain->type);
1729 if (!default_event_name) {
1730 ret = -LTTNG_ERR_FATAL;
1731 goto error;
1732 }
1733 strncpy(uevent.name, default_event_name, sizeof(uevent.name));
1734 uevent.name[sizeof(uevent.name) - 1] = '\0';
1735
1736 /*
1737 * The domain type is changed because we are about to enable the
1738 * default channel and event for the JUL domain that are hardcoded.
1739 * This happens in the UST domain.
1740 */
1741 memcpy(&tmp_dom, domain, sizeof(tmp_dom));
1742 tmp_dom.type = LTTNG_DOMAIN_UST;
1743
1744 switch (domain->type) {
1745 case LTTNG_DOMAIN_LOG4J:
1746 default_chan_name = DEFAULT_LOG4J_CHANNEL_NAME;
1747 break;
1748 case LTTNG_DOMAIN_JUL:
1749 default_chan_name = DEFAULT_JUL_CHANNEL_NAME;
1750 break;
1751 case LTTNG_DOMAIN_PYTHON:
1752 default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
1753 break;
1754 default:
1755 /* The switch/case we are in should avoid this else big problem */
1756 assert(0);
1757 }
1758
1759 {
1760 struct lttng_filter_bytecode *filter_copy = NULL;
1761
1762 if (filter) {
1763 filter_copy = zmalloc(
1764 sizeof(struct lttng_filter_bytecode)
1765 + filter->len);
1766 if (!filter_copy) {
1767 goto error;
1768 }
1769
1770 memcpy(filter_copy, filter,
1771 sizeof(struct lttng_filter_bytecode)
1772 + filter->len);
1773 }
1774
1775 ret = cmd_enable_event_internal(session, &tmp_dom,
1776 (char *) default_chan_name,
1777 &uevent, filter_expression, filter_copy,
1778 NULL, wpipe);
1779 /* We have passed ownership */
1780 filter_expression = NULL;
1781 }
1782
1783 if (ret != LTTNG_OK && ret != LTTNG_ERR_UST_EVENT_ENABLED) {
1784 goto error;
1785 }
1786
1787 /* The wild card * means that everything should be enabled. */
1788 if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
1789 ret = event_agent_enable_all(usess, agt, event, filter);
1790 filter = NULL;
1791 } else {
1792 ret = event_agent_enable(usess, agt, event, filter);
1793 filter = NULL;
1794 }
1795 if (ret != LTTNG_OK) {
1796 goto error;
1797 }
1798
1799 break;
1800 }
1801 default:
1802 ret = LTTNG_ERR_UND;
1803 goto error;
1804 }
1805
1806 ret = LTTNG_OK;
1807
1808 error:
1809 free(filter_expression);
1810 free(filter);
1811 free(exclusion);
1812 rcu_read_unlock();
1813 return ret;
1814 }
1815
1816 /*
1817 * Command LTTNG_ENABLE_EVENT processed by the client thread.
1818 * We own filter, exclusion, and filter_expression.
1819 */
1820 int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
1821 char *channel_name, struct lttng_event *event,
1822 char *filter_expression,
1823 struct lttng_filter_bytecode *filter,
1824 struct lttng_event_exclusion *exclusion,
1825 int wpipe)
1826 {
1827 return _cmd_enable_event(session, domain, channel_name, event,
1828 filter_expression, filter, exclusion, wpipe, false);
1829 }
1830
1831 /*
1832 * Enable an event which is internal to LTTng. An internal should
1833 * never be made visible to clients and are immune to checks such as
1834 * reserved names.
1835 */
1836 static int cmd_enable_event_internal(struct ltt_session *session,
1837 struct lttng_domain *domain,
1838 char *channel_name, struct lttng_event *event,
1839 char *filter_expression,
1840 struct lttng_filter_bytecode *filter,
1841 struct lttng_event_exclusion *exclusion,
1842 int wpipe)
1843 {
1844 return _cmd_enable_event(session, domain, channel_name, event,
1845 filter_expression, filter, exclusion, wpipe, true);
1846 }
1847
1848 /*
1849 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
1850 */
1851 ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
1852 {
1853 int ret;
1854 ssize_t nb_events = 0;
1855
1856 switch (domain) {
1857 case LTTNG_DOMAIN_KERNEL:
1858 nb_events = kernel_list_events(kernel_tracer_fd, events);
1859 if (nb_events < 0) {
1860 ret = LTTNG_ERR_KERN_LIST_FAIL;
1861 goto error;
1862 }
1863 break;
1864 case LTTNG_DOMAIN_UST:
1865 nb_events = ust_app_list_events(events);
1866 if (nb_events < 0) {
1867 ret = LTTNG_ERR_UST_LIST_FAIL;
1868 goto error;
1869 }
1870 break;
1871 case LTTNG_DOMAIN_LOG4J:
1872 case LTTNG_DOMAIN_JUL:
1873 case LTTNG_DOMAIN_PYTHON:
1874 nb_events = agent_list_events(events, domain);
1875 if (nb_events < 0) {
1876 ret = LTTNG_ERR_UST_LIST_FAIL;
1877 goto error;
1878 }
1879 break;
1880 default:
1881 ret = LTTNG_ERR_UND;
1882 goto error;
1883 }
1884
1885 return nb_events;
1886
1887 error:
1888 /* Return negative value to differentiate return code */
1889 return -ret;
1890 }
1891
1892 /*
1893 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
1894 */
1895 ssize_t cmd_list_tracepoint_fields(int domain,
1896 struct lttng_event_field **fields)
1897 {
1898 int ret;
1899 ssize_t nb_fields = 0;
1900
1901 switch (domain) {
1902 case LTTNG_DOMAIN_UST:
1903 nb_fields = ust_app_list_event_fields(fields);
1904 if (nb_fields < 0) {
1905 ret = LTTNG_ERR_UST_LIST_FAIL;
1906 goto error;
1907 }
1908 break;
1909 case LTTNG_DOMAIN_KERNEL:
1910 default: /* fall-through */
1911 ret = LTTNG_ERR_UND;
1912 goto error;
1913 }
1914
1915 return nb_fields;
1916
1917 error:
1918 /* Return negative value to differentiate return code */
1919 return -ret;
1920 }
1921
1922 ssize_t cmd_list_syscalls(struct lttng_event **events)
1923 {
1924 return syscall_table_list(events);
1925 }
1926
1927 /*
1928 * Command LTTNG_LIST_TRACKER_PIDS processed by the client thread.
1929 *
1930 * Called with session lock held.
1931 */
1932 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
1933 int domain, int32_t **pids)
1934 {
1935 int ret;
1936 ssize_t nr_pids = 0;
1937
1938 switch (domain) {
1939 case LTTNG_DOMAIN_KERNEL:
1940 {
1941 struct ltt_kernel_session *ksess;
1942
1943 ksess = session->kernel_session;
1944 nr_pids = kernel_list_tracker_pids(ksess, pids);
1945 if (nr_pids < 0) {
1946 ret = LTTNG_ERR_KERN_LIST_FAIL;
1947 goto error;
1948 }
1949 break;
1950 }
1951 case LTTNG_DOMAIN_UST:
1952 {
1953 struct ltt_ust_session *usess;
1954
1955 usess = session->ust_session;
1956 nr_pids = trace_ust_list_tracker_pids(usess, pids);
1957 if (nr_pids < 0) {
1958 ret = LTTNG_ERR_UST_LIST_FAIL;
1959 goto error;
1960 }
1961 break;
1962 }
1963 case LTTNG_DOMAIN_LOG4J:
1964 case LTTNG_DOMAIN_JUL:
1965 case LTTNG_DOMAIN_PYTHON:
1966 default:
1967 ret = LTTNG_ERR_UND;
1968 goto error;
1969 }
1970
1971 return nr_pids;
1972
1973 error:
1974 /* Return negative value to differentiate return code */
1975 return -ret;
1976 }
1977
1978 /*
1979 * Command LTTNG_START_TRACE processed by the client thread.
1980 *
1981 * Called with session mutex held.
1982 */
1983 int cmd_start_trace(struct ltt_session *session)
1984 {
1985 int ret;
1986 unsigned long nb_chan = 0;
1987 struct ltt_kernel_session *ksession;
1988 struct ltt_ust_session *usess;
1989
1990 assert(session);
1991
1992 /* Ease our life a bit ;) */
1993 ksession = session->kernel_session;
1994 usess = session->ust_session;
1995
1996 /* Is the session already started? */
1997 if (session->active) {
1998 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
1999 goto error;
2000 }
2001
2002 /*
2003 * Starting a session without channel is useless since after that it's not
2004 * possible to enable channel thus inform the client.
2005 */
2006 if (usess && usess->domain_global.channels) {
2007 rcu_read_lock();
2008 nb_chan += lttng_ht_get_count(usess->domain_global.channels);
2009 rcu_read_unlock();
2010 }
2011 if (ksession) {
2012 nb_chan += ksession->channel_count;
2013 }
2014 if (!nb_chan) {
2015 ret = LTTNG_ERR_NO_CHANNEL;
2016 goto error;
2017 }
2018
2019 /* Kernel tracing */
2020 if (ksession != NULL) {
2021 ret = start_kernel_session(ksession, kernel_tracer_fd);
2022 if (ret != LTTNG_OK) {
2023 goto error;
2024 }
2025 }
2026
2027 /* Flag session that trace should start automatically */
2028 if (usess) {
2029 /*
2030 * Even though the start trace might fail, flag this session active so
2031 * other application coming in are started by default.
2032 */
2033 usess->active = 1;
2034
2035 ret = ust_app_start_trace_all(usess);
2036 if (ret < 0) {
2037 ret = LTTNG_ERR_UST_START_FAIL;
2038 goto error;
2039 }
2040 }
2041
2042 /* Flag this after a successful start. */
2043 session->has_been_started = 1;
2044 session->active = 1;
2045
2046 ret = LTTNG_OK;
2047
2048 error:
2049 return ret;
2050 }
2051
2052 /*
2053 * Command LTTNG_STOP_TRACE processed by the client thread.
2054 */
2055 int cmd_stop_trace(struct ltt_session *session)
2056 {
2057 int ret;
2058 struct ltt_kernel_channel *kchan;
2059 struct ltt_kernel_session *ksession;
2060 struct ltt_ust_session *usess;
2061
2062 assert(session);
2063
2064 /* Short cut */
2065 ksession = session->kernel_session;
2066 usess = session->ust_session;
2067
2068 /* Session is not active. Skip everythong and inform the client. */
2069 if (!session->active) {
2070 ret = LTTNG_ERR_TRACE_ALREADY_STOPPED;
2071 goto error;
2072 }
2073
2074 /* Kernel tracer */
2075 if (ksession && ksession->active) {
2076 DBG("Stop kernel tracing");
2077
2078 /* Flush metadata if exist */
2079 if (ksession->metadata_stream_fd >= 0) {
2080 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2081 if (ret < 0) {
2082 ERR("Kernel metadata flush failed");
2083 }
2084 }
2085
2086 /* Flush all buffers before stopping */
2087 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2088 ret = kernel_flush_buffer(kchan);
2089 if (ret < 0) {
2090 ERR("Kernel flush buffer error");
2091 }
2092 }
2093
2094 ret = kernel_stop_session(ksession);
2095 if (ret < 0) {
2096 ret = LTTNG_ERR_KERN_STOP_FAIL;
2097 goto error;
2098 }
2099
2100 kernel_wait_quiescent(kernel_tracer_fd);
2101
2102 ksession->active = 0;
2103 }
2104
2105 if (usess && usess->active) {
2106 /*
2107 * Even though the stop trace might fail, flag this session inactive so
2108 * other application coming in are not started by default.
2109 */
2110 usess->active = 0;
2111
2112 ret = ust_app_stop_trace_all(usess);
2113 if (ret < 0) {
2114 ret = LTTNG_ERR_UST_STOP_FAIL;
2115 goto error;
2116 }
2117 }
2118
2119 /* Flag inactive after a successful stop. */
2120 session->active = 0;
2121 ret = LTTNG_OK;
2122
2123 error:
2124 return ret;
2125 }
2126
2127 /*
2128 * Command LTTNG_SET_CONSUMER_URI processed by the client thread.
2129 */
2130 int cmd_set_consumer_uri(struct ltt_session *session, size_t nb_uri,
2131 struct lttng_uri *uris)
2132 {
2133 int ret, i;
2134 struct ltt_kernel_session *ksess = session->kernel_session;
2135 struct ltt_ust_session *usess = session->ust_session;
2136
2137 assert(session);
2138 assert(uris);
2139 assert(nb_uri > 0);
2140
2141 /* Can't set consumer URI if the session is active. */
2142 if (session->active) {
2143 ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
2144 goto error;
2145 }
2146
2147 /* Set the "global" consumer URIs */
2148 for (i = 0; i < nb_uri; i++) {
2149 ret = add_uri_to_consumer(session->consumer,
2150 &uris[i], 0, session->name);
2151 if (ret != LTTNG_OK) {
2152 goto error;
2153 }
2154 }
2155
2156 /* Set UST session URIs */
2157 if (session->ust_session) {
2158 for (i = 0; i < nb_uri; i++) {
2159 ret = add_uri_to_consumer(
2160 session->ust_session->consumer,
2161 &uris[i], LTTNG_DOMAIN_UST,
2162 session->name);
2163 if (ret != LTTNG_OK) {
2164 goto error;
2165 }
2166 }
2167 }
2168
2169 /* Set kernel session URIs */
2170 if (session->kernel_session) {
2171 for (i = 0; i < nb_uri; i++) {
2172 ret = add_uri_to_consumer(
2173 session->kernel_session->consumer,
2174 &uris[i], LTTNG_DOMAIN_KERNEL,
2175 session->name);
2176 if (ret != LTTNG_OK) {
2177 goto error;
2178 }
2179 }
2180 }
2181
2182 /*
2183 * Make sure to set the session in output mode after we set URI since a
2184 * session can be created without URL (thus flagged in no output mode).
2185 */
2186 session->output_traces = 1;
2187 if (ksess) {
2188 ksess->output_traces = 1;
2189 }
2190
2191 if (usess) {
2192 usess->output_traces = 1;
2193 }
2194
2195 /* All good! */
2196 ret = LTTNG_OK;
2197
2198 error:
2199 return ret;
2200 }
2201
2202 /*
2203 * Command LTTNG_CREATE_SESSION processed by the client thread.
2204 */
2205 int cmd_create_session_uri(char *name, struct lttng_uri *uris,
2206 size_t nb_uri, lttng_sock_cred *creds, unsigned int live_timer)
2207 {
2208 int ret;
2209 struct ltt_session *session;
2210
2211 assert(name);
2212 assert(creds);
2213
2214 /*
2215 * Verify if the session already exist
2216 *
2217 * XXX: There is no need for the session lock list here since the caller
2218 * (process_client_msg) is holding it. We might want to change that so a
2219 * single command does not lock the entire session list.
2220 */
2221 session = session_find_by_name(name);
2222 if (session != NULL) {
2223 ret = LTTNG_ERR_EXIST_SESS;
2224 goto find_error;
2225 }
2226
2227 /* Create tracing session in the registry */
2228 ret = session_create(name, LTTNG_SOCK_GET_UID_CRED(creds),
2229 LTTNG_SOCK_GET_GID_CRED(creds));
2230 if (ret != LTTNG_OK) {
2231 goto session_error;
2232 }
2233
2234 /*
2235 * Get the newly created session pointer back
2236 *
2237 * XXX: There is no need for the session lock list here since the caller
2238 * (process_client_msg) is holding it. We might want to change that so a
2239 * single command does not lock the entire session list.
2240 */
2241 session = session_find_by_name(name);
2242 assert(session);
2243
2244 session->live_timer = live_timer;
2245 /* Create default consumer output for the session not yet created. */
2246 session->consumer = consumer_create_output(CONSUMER_DST_LOCAL);
2247 if (session->consumer == NULL) {
2248 ret = LTTNG_ERR_FATAL;
2249 goto consumer_error;
2250 }
2251
2252 if (uris) {
2253 ret = cmd_set_consumer_uri(session, nb_uri, uris);
2254 if (ret != LTTNG_OK) {
2255 goto consumer_error;
2256 }
2257 session->output_traces = 1;
2258 } else {
2259 session->output_traces = 0;
2260 DBG2("Session %s created with no output", session->name);
2261 }
2262
2263 session->consumer->enabled = 1;
2264
2265 return LTTNG_OK;
2266
2267 consumer_error:
2268 session_destroy(session);
2269 session_error:
2270 find_error:
2271 return ret;
2272 }
2273
2274 /*
2275 * Command LTTNG_CREATE_SESSION_SNAPSHOT processed by the client thread.
2276 */
2277 int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
2278 size_t nb_uri, lttng_sock_cred *creds)
2279 {
2280 int ret;
2281 struct ltt_session *session;
2282 struct snapshot_output *new_output = NULL;
2283
2284 assert(name);
2285 assert(creds);
2286
2287 /*
2288 * Create session in no output mode with URIs set to NULL. The uris we've
2289 * received are for a default snapshot output if one.
2290 */
2291 ret = cmd_create_session_uri(name, NULL, 0, creds, -1);
2292 if (ret != LTTNG_OK) {
2293 goto error;
2294 }
2295
2296 /* Get the newly created session pointer back. This should NEVER fail. */
2297 session = session_find_by_name(name);
2298 assert(session);
2299
2300 /* Flag session for snapshot mode. */
2301 session->snapshot_mode = 1;
2302
2303 /* Skip snapshot output creation if no URI is given. */
2304 if (nb_uri == 0) {
2305 goto end;
2306 }
2307
2308 new_output = snapshot_output_alloc();
2309 if (!new_output) {
2310 ret = LTTNG_ERR_NOMEM;
2311 goto error_snapshot_alloc;
2312 }
2313
2314 ret = snapshot_output_init_with_uri(DEFAULT_SNAPSHOT_MAX_SIZE, NULL,
2315 uris, nb_uri, session->consumer, new_output, &session->snapshot);
2316 if (ret < 0) {
2317 if (ret == -ENOMEM) {
2318 ret = LTTNG_ERR_NOMEM;
2319 } else {
2320 ret = LTTNG_ERR_INVALID;
2321 }
2322 goto error_snapshot;
2323 }
2324
2325 rcu_read_lock();
2326 snapshot_add_output(&session->snapshot, new_output);
2327 rcu_read_unlock();
2328
2329 end:
2330 return LTTNG_OK;
2331
2332 error_snapshot:
2333 snapshot_output_destroy(new_output);
2334 error_snapshot_alloc:
2335 session_destroy(session);
2336 error:
2337 return ret;
2338 }
2339
2340 /*
2341 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2342 *
2343 * Called with session lock held.
2344 */
2345 int cmd_destroy_session(struct ltt_session *session, int wpipe)
2346 {
2347 int ret;
2348 struct ltt_ust_session *usess;
2349 struct ltt_kernel_session *ksess;
2350
2351 /* Safety net */
2352 assert(session);
2353
2354 usess = session->ust_session;
2355 ksess = session->kernel_session;
2356
2357 /* Clean kernel session teardown */
2358 kernel_destroy_session(ksess);
2359
2360 /* UST session teardown */
2361 if (usess) {
2362 /* Close any relayd session */
2363 consumer_output_send_destroy_relayd(usess->consumer);
2364
2365 /* Destroy every UST application related to this session. */
2366 ret = ust_app_destroy_trace_all(usess);
2367 if (ret) {
2368 ERR("Error in ust_app_destroy_trace_all");
2369 }
2370
2371 /* Clean up the rest. */
2372 trace_ust_destroy_session(usess);
2373 }
2374
2375 /*
2376 * Must notify the kernel thread here to update it's poll set in order to
2377 * remove the channel(s)' fd just destroyed.
2378 */
2379 ret = notify_thread_pipe(wpipe);
2380 if (ret < 0) {
2381 PERROR("write kernel poll pipe");
2382 }
2383
2384 ret = session_destroy(session);
2385
2386 return ret;
2387 }
2388
2389 /*
2390 * Command LTTNG_CALIBRATE processed by the client thread.
2391 */
2392 int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2393 {
2394 int ret;
2395
2396 switch (domain) {
2397 case LTTNG_DOMAIN_KERNEL:
2398 {
2399 struct lttng_kernel_calibrate kcalibrate;
2400
2401 switch (calibrate->type) {
2402 case LTTNG_CALIBRATE_FUNCTION:
2403 default:
2404 /* Default and only possible calibrate option. */
2405 kcalibrate.type = LTTNG_KERNEL_CALIBRATE_KRETPROBE;
2406 break;
2407 }
2408
2409 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2410 if (ret < 0) {
2411 ret = LTTNG_ERR_KERN_ENABLE_FAIL;
2412 goto error;
2413 }
2414 break;
2415 }
2416 case LTTNG_DOMAIN_UST:
2417 {
2418 struct lttng_ust_calibrate ucalibrate;
2419
2420 switch (calibrate->type) {
2421 case LTTNG_CALIBRATE_FUNCTION:
2422 default:
2423 /* Default and only possible calibrate option. */
2424 ucalibrate.type = LTTNG_UST_CALIBRATE_TRACEPOINT;
2425 break;
2426 }
2427
2428 ret = ust_app_calibrate_glb(&ucalibrate);
2429 if (ret < 0) {
2430 ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
2431 goto error;
2432 }
2433 break;
2434 }
2435 default:
2436 ret = LTTNG_ERR_UND;
2437 goto error;
2438 }
2439
2440 ret = LTTNG_OK;
2441
2442 error:
2443 return ret;
2444 }
2445
2446 /*
2447 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2448 */
2449 int cmd_register_consumer(struct ltt_session *session, int domain,
2450 const char *sock_path, struct consumer_data *cdata)
2451 {
2452 int ret, sock;
2453 struct consumer_socket *socket = NULL;
2454
2455 assert(session);
2456 assert(cdata);
2457 assert(sock_path);
2458
2459 switch (domain) {
2460 case LTTNG_DOMAIN_KERNEL:
2461 {
2462 struct ltt_kernel_session *ksess = session->kernel_session;
2463
2464 assert(ksess);
2465
2466 /* Can't register a consumer if there is already one */
2467 if (ksess->consumer_fds_sent != 0) {
2468 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2469 goto error;
2470 }
2471
2472 sock = lttcomm_connect_unix_sock(sock_path);
2473 if (sock < 0) {
2474 ret = LTTNG_ERR_CONNECT_FAIL;
2475 goto error;
2476 }
2477 cdata->cmd_sock = sock;
2478
2479 socket = consumer_allocate_socket(&cdata->cmd_sock);
2480 if (socket == NULL) {
2481 ret = close(sock);
2482 if (ret < 0) {
2483 PERROR("close register consumer");
2484 }
2485 cdata->cmd_sock = -1;
2486 ret = LTTNG_ERR_FATAL;
2487 goto error;
2488 }
2489
2490 socket->lock = zmalloc(sizeof(pthread_mutex_t));
2491 if (socket->lock == NULL) {
2492 PERROR("zmalloc pthread mutex");
2493 ret = LTTNG_ERR_FATAL;
2494 goto error;
2495 }
2496 pthread_mutex_init(socket->lock, NULL);
2497 socket->registered = 1;
2498
2499 rcu_read_lock();
2500 consumer_add_socket(socket, ksess->consumer);
2501 rcu_read_unlock();
2502
2503 pthread_mutex_lock(&cdata->pid_mutex);
2504 cdata->pid = -1;
2505 pthread_mutex_unlock(&cdata->pid_mutex);
2506
2507 break;
2508 }
2509 default:
2510 /* TODO: Userspace tracing */
2511 ret = LTTNG_ERR_UND;
2512 goto error;
2513 }
2514
2515 return LTTNG_OK;
2516
2517 error:
2518 if (socket) {
2519 consumer_destroy_socket(socket);
2520 }
2521 return ret;
2522 }
2523
2524 /*
2525 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2526 */
2527 ssize_t cmd_list_domains(struct ltt_session *session,
2528 struct lttng_domain **domains)
2529 {
2530 int ret, index = 0;
2531 ssize_t nb_dom = 0;
2532 struct agent *agt;
2533 struct lttng_ht_iter iter;
2534
2535 if (session->kernel_session != NULL) {
2536 DBG3("Listing domains found kernel domain");
2537 nb_dom++;
2538 }
2539
2540 if (session->ust_session != NULL) {
2541 DBG3("Listing domains found UST global domain");
2542 nb_dom++;
2543
2544 rcu_read_lock();
2545 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2546 agt, node.node) {
2547 if (agt->being_used) {
2548 nb_dom++;
2549 }
2550 }
2551 rcu_read_unlock();
2552 }
2553
2554 if (!nb_dom) {
2555 goto end;
2556 }
2557
2558 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2559 if (*domains == NULL) {
2560 ret = LTTNG_ERR_FATAL;
2561 goto error;
2562 }
2563
2564 if (session->kernel_session != NULL) {
2565 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2566
2567 /* Kernel session buffer type is always GLOBAL */
2568 (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
2569
2570 index++;
2571 }
2572
2573 if (session->ust_session != NULL) {
2574 (*domains)[index].type = LTTNG_DOMAIN_UST;
2575 (*domains)[index].buf_type = session->ust_session->buffer_type;
2576 index++;
2577
2578 rcu_read_lock();
2579 cds_lfht_for_each_entry(session->ust_session->agents->ht, &iter.iter,
2580 agt, node.node) {
2581 if (agt->being_used) {
2582 (*domains)[index].type = agt->domain;
2583 (*domains)[index].buf_type = session->ust_session->buffer_type;
2584 index++;
2585 }
2586 }
2587 rcu_read_unlock();
2588 }
2589 end:
2590 return nb_dom;
2591
2592 error:
2593 /* Return negative value to differentiate return code */
2594 return -ret;
2595 }
2596
2597
2598 /*
2599 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2600 */
2601 ssize_t cmd_list_channels(int domain, struct ltt_session *session,
2602 struct lttng_channel **channels)
2603 {
2604 int ret;
2605 ssize_t nb_chan = 0;
2606
2607 switch (domain) {
2608 case LTTNG_DOMAIN_KERNEL:
2609 if (session->kernel_session != NULL) {
2610 nb_chan = session->kernel_session->channel_count;
2611 }
2612 DBG3("Number of kernel channels %zd", nb_chan);
2613 if (nb_chan <= 0) {
2614 ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
2615 }
2616 break;
2617 case LTTNG_DOMAIN_UST:
2618 if (session->ust_session != NULL) {
2619 rcu_read_lock();
2620 nb_chan = lttng_ht_get_count(
2621 session->ust_session->domain_global.channels);
2622 rcu_read_unlock();
2623 }
2624 DBG3("Number of UST global channels %zd", nb_chan);
2625 if (nb_chan < 0) {
2626 ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
2627 goto error;
2628 }
2629 break;
2630 default:
2631 ret = LTTNG_ERR_UND;
2632 goto error;
2633 }
2634
2635 if (nb_chan > 0) {
2636 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
2637 if (*channels == NULL) {
2638 ret = LTTNG_ERR_FATAL;
2639 goto error;
2640 }
2641
2642 list_lttng_channels(domain, session, *channels);
2643 }
2644
2645 return nb_chan;
2646
2647 error:
2648 /* Return negative value to differentiate return code */
2649 return -ret;
2650 }
2651
2652 /*
2653 * Command LTTNG_LIST_EVENTS processed by the client thread.
2654 */
2655 ssize_t cmd_list_events(int domain, struct ltt_session *session,
2656 char *channel_name, struct lttng_event **events)
2657 {
2658 int ret = 0;
2659 ssize_t nb_event = 0;
2660
2661 switch (domain) {
2662 case LTTNG_DOMAIN_KERNEL:
2663 if (session->kernel_session != NULL) {
2664 nb_event = list_lttng_kernel_events(channel_name,
2665 session->kernel_session, events);
2666 }
2667 break;
2668 case LTTNG_DOMAIN_UST:
2669 {
2670 if (session->ust_session != NULL) {
2671 nb_event = list_lttng_ust_global_events(channel_name,
2672 &session->ust_session->domain_global, events);
2673 }
2674 break;
2675 }
2676 case LTTNG_DOMAIN_LOG4J:
2677 case LTTNG_DOMAIN_JUL:
2678 case LTTNG_DOMAIN_PYTHON:
2679 if (session->ust_session) {
2680 struct lttng_ht_iter iter;
2681 struct agent *agt;
2682
2683 rcu_read_lock();
2684 cds_lfht_for_each_entry(session->ust_session->agents->ht,
2685 &iter.iter, agt, node.node) {
2686 nb_event = list_lttng_agent_events(agt, events);
2687 }
2688 rcu_read_unlock();
2689 }
2690 break;
2691 default:
2692 ret = LTTNG_ERR_UND;
2693 goto error;
2694 }
2695
2696 return nb_event;
2697
2698 error:
2699 /* Return negative value to differentiate return code */
2700 return -ret;
2701 }
2702
2703 /*
2704 * Using the session list, filled a lttng_session array to send back to the
2705 * client for session listing.
2706 *
2707 * The session list lock MUST be acquired before calling this function. Use
2708 * session_lock_list() and session_unlock_list().
2709 */
2710 void cmd_list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2711 gid_t gid)
2712 {
2713 int ret;
2714 unsigned int i = 0;
2715 struct ltt_session *session;
2716 struct ltt_session_list *list = session_get_list();
2717
2718 DBG("Getting all available session for UID %d GID %d",
2719 uid, gid);
2720 /*
2721 * Iterate over session list and append data after the control struct in
2722 * the buffer.
2723 */
2724 cds_list_for_each_entry(session, &list->head, list) {
2725 /*
2726 * Only list the sessions the user can control.
2727 */
2728 if (!session_access_ok(session, uid, gid)) {
2729 continue;
2730 }
2731
2732 struct ltt_kernel_session *ksess = session->kernel_session;
2733 struct ltt_ust_session *usess = session->ust_session;
2734
2735 if (session->consumer->type == CONSUMER_DST_NET ||
2736 (ksess && ksess->consumer->type == CONSUMER_DST_NET) ||
2737 (usess && usess->consumer->type == CONSUMER_DST_NET)) {
2738 ret = build_network_session_path(sessions[i].path,
2739 sizeof(sessions[i].path), session);
2740 } else {
2741 ret = snprintf(sessions[i].path, sizeof(sessions[i].path), "%s",
2742 session->consumer->dst.trace_path);
2743 }
2744 if (ret < 0) {
2745 PERROR("snprintf session path");
2746 continue;
2747 }
2748
2749 strncpy(sessions[i].name, session->name, NAME_MAX);
2750 sessions[i].name[NAME_MAX - 1] = '\0';
2751 sessions[i].enabled = session->active;
2752 sessions[i].snapshot_mode = session->snapshot_mode;
2753 sessions[i].live_timer_interval = session->live_timer;
2754 i++;
2755 }
2756 }
2757
2758 /*
2759 * Command LTTNG_DATA_PENDING returning 0 if the data is NOT pending meaning
2760 * ready for trace analysis (or any kind of reader) or else 1 for pending data.
2761 */
2762 int cmd_data_pending(struct ltt_session *session)
2763 {
2764 int ret;
2765 struct ltt_kernel_session *ksess = session->kernel_session;
2766 struct ltt_ust_session *usess = session->ust_session;
2767
2768 assert(session);
2769
2770 /* Session MUST be stopped to ask for data availability. */
2771 if (session->active) {
2772 ret = LTTNG_ERR_SESSION_STARTED;
2773 goto error;
2774 } else {
2775 /*
2776 * If stopped, just make sure we've started before else the above call
2777 * will always send that there is data pending.
2778 *
2779 * The consumer assumes that when the data pending command is received,
2780 * the trace has been started before or else no output data is written
2781 * by the streams which is a condition for data pending. So, this is
2782 * *VERY* important that we don't ask the consumer before a start
2783 * trace.
2784 */
2785 if (!session->has_been_started) {
2786 ret = 0;
2787 goto error;
2788 }
2789 }
2790
2791 if (ksess && ksess->consumer) {
2792 ret = consumer_is_data_pending(ksess->id, ksess->consumer);
2793 if (ret == 1) {
2794 /* Data is still being extracted for the kernel. */
2795 goto error;
2796 }
2797 }
2798
2799 if (usess && usess->consumer) {
2800 ret = consumer_is_data_pending(usess->id, usess->consumer);
2801 if (ret == 1) {
2802 /* Data is still being extracted for the kernel. */
2803 goto error;
2804 }
2805 }
2806
2807 /* Data is ready to be read by a viewer */
2808 ret = 0;
2809
2810 error:
2811 return ret;
2812 }
2813
2814 /*
2815 * Command LTTNG_SNAPSHOT_ADD_OUTPUT from the lttng ctl library.
2816 *
2817 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2818 */
2819 int cmd_snapshot_add_output(struct ltt_session *session,
2820 struct lttng_snapshot_output *output, uint32_t *id)
2821 {
2822 int ret;
2823 struct snapshot_output *new_output;
2824
2825 assert(session);
2826 assert(output);
2827
2828 DBG("Cmd snapshot add output for session %s", session->name);
2829
2830 /*
2831 * Permission denied to create an output if the session is not
2832 * set in no output mode.
2833 */
2834 if (session->output_traces) {
2835 ret = LTTNG_ERR_EPERM;
2836 goto error;
2837 }
2838
2839 /* Only one output is allowed until we have the "tee" feature. */
2840 if (session->snapshot.nb_output == 1) {
2841 ret = LTTNG_ERR_SNAPSHOT_OUTPUT_EXIST;
2842 goto error;
2843 }
2844
2845 new_output = snapshot_output_alloc();
2846 if (!new_output) {
2847 ret = LTTNG_ERR_NOMEM;
2848 goto error;
2849 }
2850
2851 ret = snapshot_output_init(output->max_size, output->name,
2852 output->ctrl_url, output->data_url, session->consumer, new_output,
2853 &session->snapshot);
2854 if (ret < 0) {
2855 if (ret == -ENOMEM) {
2856 ret = LTTNG_ERR_NOMEM;
2857 } else {
2858 ret = LTTNG_ERR_INVALID;
2859 }
2860 goto free_error;
2861 }
2862
2863 rcu_read_lock();
2864 snapshot_add_output(&session->snapshot, new_output);
2865 if (id) {
2866 *id = new_output->id;
2867 }
2868 rcu_read_unlock();
2869
2870 return LTTNG_OK;
2871
2872 free_error:
2873 snapshot_output_destroy(new_output);
2874 error:
2875 return ret;
2876 }
2877
2878 /*
2879 * Command LTTNG_SNAPSHOT_DEL_OUTPUT from lib lttng ctl.
2880 *
2881 * Return LTTNG_OK on success or else a LTTNG_ERR code.
2882 */
2883 int cmd_snapshot_del_output(struct ltt_session *session,
2884 struct lttng_snapshot_output *output)
2885 {
2886 int ret;
2887 struct snapshot_output *sout = NULL;
2888
2889 assert(session);
2890 assert(output);
2891
2892 rcu_read_lock();
2893
2894 /*
2895 * Permission denied to create an output if the session is not
2896 * set in no output mode.
2897 */
2898 if (session->output_traces) {
2899 ret = LTTNG_ERR_EPERM;
2900 goto error;
2901 }
2902
2903 if (output->id) {
2904 DBG("Cmd snapshot del output id %" PRIu32 " for session %s", output->id,
2905 session->name);
2906 sout = snapshot_find_output_by_id(output->id, &session->snapshot);
2907 } else if (*output->name != '\0') {
2908 DBG("Cmd snapshot del output name %s for session %s", output->name,
2909 session->name);
2910 sout = snapshot_find_output_by_name(output->name, &session->snapshot);
2911 }
2912 if (!sout) {
2913 ret = LTTNG_ERR_INVALID;
2914 goto error;
2915 }
2916
2917 snapshot_delete_output(&session->snapshot, sout);
2918 snapshot_output_destroy(sout);
2919 ret = LTTNG_OK;
2920
2921 error:
2922 rcu_read_unlock();
2923 return ret;
2924 }
2925
2926 /*
2927 * Command LTTNG_SNAPSHOT_LIST_OUTPUT from lib lttng ctl.
2928 *
2929 * If no output is available, outputs is untouched and 0 is returned.
2930 *
2931 * Return the size of the newly allocated outputs or a negative LTTNG_ERR code.
2932 */
2933 ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
2934 struct lttng_snapshot_output **outputs)
2935 {
2936 int ret, idx = 0;
2937 struct lttng_snapshot_output *list = NULL;
2938 struct lttng_ht_iter iter;
2939 struct snapshot_output *output;
2940
2941 assert(session);
2942 assert(outputs);
2943
2944 DBG("Cmd snapshot list outputs for session %s", session->name);
2945
2946 /*
2947 * Permission denied to create an output if the session is not
2948 * set in no output mode.
2949 */
2950 if (session->output_traces) {
2951 ret = -LTTNG_ERR_EPERM;
2952 goto error;
2953 }
2954
2955 if (session->snapshot.nb_output == 0) {
2956 ret = 0;
2957 goto error;
2958 }
2959
2960 list = zmalloc(session->snapshot.nb_output * sizeof(*list));
2961 if (!list) {
2962 ret = -LTTNG_ERR_NOMEM;
2963 goto error;
2964 }
2965
2966 /* Copy list from session to the new list object. */
2967 rcu_read_lock();
2968 cds_lfht_for_each_entry(session->snapshot.output_ht->ht, &iter.iter,
2969 output, node.node) {
2970 assert(output->consumer);
2971 list[idx].id = output->id;
2972 list[idx].max_size = output->max_size;
2973 strncpy(list[idx].name, output->name, sizeof(list[idx].name));
2974 if (output->consumer->type == CONSUMER_DST_LOCAL) {
2975 strncpy(list[idx].ctrl_url, output->consumer->dst.trace_path,
2976 sizeof(list[idx].ctrl_url));
2977 } else {
2978 /* Control URI. */
2979 ret = uri_to_str_url(&output->consumer->dst.net.control,
2980 list[idx].ctrl_url, sizeof(list[idx].ctrl_url));
2981 if (ret < 0) {
2982 ret = -LTTNG_ERR_NOMEM;
2983 goto error;
2984 }
2985
2986 /* Data URI. */
2987 ret = uri_to_str_url(&output->consumer->dst.net.data,
2988 list[idx].data_url, sizeof(list[idx].data_url));
2989 if (ret < 0) {
2990 ret = -LTTNG_ERR_NOMEM;
2991 goto error;
2992 }
2993 }
2994 idx++;
2995 }
2996
2997 *outputs = list;
2998 list = NULL;
2999 ret = session->snapshot.nb_output;
3000 error:
3001 free(list);
3002 rcu_read_unlock();
3003 return ret;
3004 }
3005
3006 /*
3007 * Send relayd sockets from snapshot output to consumer. Ignore request if the
3008 * snapshot output is *not* set with a remote destination.
3009 *
3010 * Return 0 on success or a LTTNG_ERR code.
3011 */
3012 static int set_relayd_for_snapshot(struct consumer_output *consumer,
3013 struct snapshot_output *snap_output, struct ltt_session *session)
3014 {
3015 int ret = LTTNG_OK;
3016 struct lttng_ht_iter iter;
3017 struct consumer_socket *socket;
3018
3019 assert(consumer);
3020 assert(snap_output);
3021 assert(session);
3022
3023 DBG2("Set relayd object from snapshot output");
3024
3025 /* Ignore if snapshot consumer output is not network. */
3026 if (snap_output->consumer->type != CONSUMER_DST_NET) {
3027 goto error;
3028 }
3029
3030 /*
3031 * For each consumer socket, create and send the relayd object of the
3032 * snapshot output.
3033 */
3034 rcu_read_lock();
3035 cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
3036 socket, node.node) {
3037 ret = send_consumer_relayd_sockets(0, session->id,
3038 snap_output->consumer, socket,
3039 session->name, session->hostname,
3040 session->live_timer);
3041 if (ret != LTTNG_OK) {
3042 rcu_read_unlock();
3043 goto error;
3044 }
3045 }
3046 rcu_read_unlock();
3047
3048 error:
3049 return ret;
3050 }
3051
3052 /*
3053 * Record a kernel snapshot.
3054 *
3055 * Return LTTNG_OK on success or a LTTNG_ERR code.
3056 */
3057 static int record_kernel_snapshot(struct ltt_kernel_session *ksess,
3058 struct snapshot_output *output, struct ltt_session *session,
3059 int wait, uint64_t nb_packets_per_stream)
3060 {
3061 int ret;
3062
3063 assert(ksess);
3064 assert(output);
3065 assert(session);
3066
3067 /* Get the datetime for the snapshot output directory. */
3068 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
3069 sizeof(output->datetime));
3070 if (!ret) {
3071 ret = LTTNG_ERR_INVALID;
3072 goto error;
3073 }
3074
3075 /*
3076 * Copy kernel session sockets so we can communicate with the right
3077 * consumer for the snapshot record command.
3078 */
3079 ret = consumer_copy_sockets(output->consumer, ksess->consumer);
3080 if (ret < 0) {
3081 ret = LTTNG_ERR_NOMEM;
3082 goto error;
3083 }
3084
3085 ret = set_relayd_for_snapshot(ksess->consumer, output, session);
3086 if (ret != LTTNG_OK) {
3087 goto error_snapshot;
3088 }
3089
3090 ret = kernel_snapshot_record(ksess, output, wait, nb_packets_per_stream);
3091 if (ret != LTTNG_OK) {
3092 goto error_snapshot;
3093 }
3094
3095 ret = LTTNG_OK;
3096 goto end;
3097
3098 error_snapshot:
3099 /* Clean up copied sockets so this output can use some other later on. */
3100 consumer_destroy_output_sockets(output->consumer);
3101 error:
3102 end:
3103 return ret;
3104 }
3105
3106 /*
3107 * Record a UST snapshot.
3108 *
3109 * Return 0 on success or a LTTNG_ERR error code.
3110 */
3111 static int record_ust_snapshot(struct ltt_ust_session *usess,
3112 struct snapshot_output *output, struct ltt_session *session,
3113 int wait, uint64_t nb_packets_per_stream)
3114 {
3115 int ret;
3116
3117 assert(usess);
3118 assert(output);
3119 assert(session);
3120
3121 /* Get the datetime for the snapshot output directory. */
3122 ret = utils_get_current_time_str("%Y%m%d-%H%M%S", output->datetime,
3123 sizeof(output->datetime));
3124 if (!ret) {
3125 ret = LTTNG_ERR_INVALID;
3126 goto error;
3127 }
3128
3129 /*
3130 * Copy UST session sockets so we can communicate with the right
3131 * consumer for the snapshot record command.
3132 */
3133 ret = consumer_copy_sockets(output->consumer, usess->consumer);
3134 if (ret < 0) {
3135 ret = LTTNG_ERR_NOMEM;
3136 goto error;
3137 }
3138
3139 ret = set_relayd_for_snapshot(usess->consumer, output, session);
3140 if (ret != LTTNG_OK) {
3141 goto error_snapshot;
3142 }
3143
3144 ret = ust_app_snapshot_record(usess, output, wait, nb_packets_per_stream);
3145 if (ret < 0) {
3146 switch (-ret) {
3147 case EINVAL:
3148 ret = LTTNG_ERR_INVALID;
3149 break;
3150 case ENODATA:
3151 ret = LTTNG_ERR_SNAPSHOT_NODATA;
3152 break;
3153 default:
3154 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3155 break;
3156 }
3157 goto error_snapshot;
3158 }
3159
3160 ret = LTTNG_OK;
3161
3162 error_snapshot:
3163 /* Clean up copied sockets so this output can use some other later on. */
3164 consumer_destroy_output_sockets(output->consumer);
3165 error:
3166 return ret;
3167 }
3168
3169 static
3170 uint64_t get_session_size_one_more_packet_per_stream(struct ltt_session *session,
3171 uint64_t cur_nr_packets)
3172 {
3173 uint64_t tot_size = 0;
3174
3175 if (session->kernel_session) {
3176 struct ltt_kernel_channel *chan;
3177 struct ltt_kernel_session *ksess = session->kernel_session;
3178
3179 cds_list_for_each_entry(chan, &ksess->channel_list.head, list) {
3180 if (cur_nr_packets >= chan->channel->attr.num_subbuf) {
3181 /*
3182 * Don't take channel into account if we
3183 * already grab all its packets.
3184 */
3185 continue;
3186 }
3187 tot_size += chan->channel->attr.subbuf_size
3188 * chan->stream_count;
3189 }
3190 }
3191
3192 if (session->ust_session) {
3193 struct ltt_ust_session *usess = session->ust_session;
3194
3195 tot_size += ust_app_get_size_one_more_packet_per_stream(usess,
3196 cur_nr_packets);
3197 }
3198
3199 return tot_size;
3200 }
3201
3202 /*
3203 * Calculate the number of packets we can grab from each stream that
3204 * fits within the overall snapshot max size.
3205 *
3206 * Returns -1 on error, 0 means infinite number of packets, else > 0 is
3207 * the number of packets per stream.
3208 *
3209 * TODO: this approach is not perfect: we consider the worse case
3210 * (packet filling the sub-buffers) as an upper bound, but we could do
3211 * better if we do this calculation while we actually grab the packet
3212 * content: we would know how much padding we don't actually store into
3213 * the file.
3214 *
3215 * This algorithm is currently bounded by the number of packets per
3216 * stream.
3217 *
3218 * Since we call this algorithm before actually grabbing the data, it's
3219 * an approximation: for instance, applications could appear/disappear
3220 * in between this call and actually grabbing data.
3221 */
3222 static
3223 int64_t get_session_nb_packets_per_stream(struct ltt_session *session, uint64_t max_size)
3224 {
3225 int64_t size_left;
3226 uint64_t cur_nb_packets = 0;
3227
3228 if (!max_size) {
3229 return 0; /* Infinite */
3230 }
3231
3232 size_left = max_size;
3233 for (;;) {
3234 uint64_t one_more_packet_tot_size;
3235
3236 one_more_packet_tot_size = get_session_size_one_more_packet_per_stream(session,
3237 cur_nb_packets);
3238 if (!one_more_packet_tot_size) {
3239 /* We are already grabbing all packets. */
3240 break;
3241 }
3242 size_left -= one_more_packet_tot_size;
3243 if (size_left < 0) {
3244 break;
3245 }
3246 cur_nb_packets++;
3247 }
3248 if (!cur_nb_packets) {
3249 /* Not enough room to grab one packet of each stream, error. */
3250 return -1;
3251 }
3252 return cur_nb_packets;
3253 }
3254
3255 /*
3256 * Command LTTNG_SNAPSHOT_RECORD from lib lttng ctl.
3257 *
3258 * The wait parameter is ignored so this call always wait for the snapshot to
3259 * complete before returning.
3260 *
3261 * Return LTTNG_OK on success or else a LTTNG_ERR code.
3262 */
3263 int cmd_snapshot_record(struct ltt_session *session,
3264 struct lttng_snapshot_output *output, int wait)
3265 {
3266 int ret = LTTNG_OK;
3267 unsigned int use_tmp_output = 0;
3268 struct snapshot_output tmp_output;
3269 unsigned int snapshot_success = 0;
3270
3271 assert(session);
3272 assert(output);
3273
3274 DBG("Cmd snapshot record for session %s", session->name);
3275
3276 /*
3277 * Permission denied to create an output if the session is not
3278 * set in no output mode.
3279 */
3280 if (session->output_traces) {
3281 ret = LTTNG_ERR_EPERM;
3282 goto error;
3283 }
3284
3285 /* The session needs to be started at least once. */
3286 if (!session->has_been_started) {
3287 ret = LTTNG_ERR_START_SESSION_ONCE;
3288 goto error;
3289 }
3290
3291 /* Use temporary output for the session. */
3292 if (*output->ctrl_url != '\0') {
3293 ret = snapshot_output_init(output->max_size, output->name,
3294 output->ctrl_url, output->data_url, session->consumer,
3295 &tmp_output, NULL);
3296 if (ret < 0) {
3297 if (ret == -ENOMEM) {
3298 ret = LTTNG_ERR_NOMEM;
3299 } else {
3300 ret = LTTNG_ERR_INVALID;
3301 }
3302 goto error;
3303 }
3304 /* Use the global session count for the temporary snapshot. */
3305 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3306 use_tmp_output = 1;
3307 }
3308
3309 if (session->kernel_session) {
3310 struct ltt_kernel_session *ksess = session->kernel_session;
3311
3312 if (use_tmp_output) {
3313 int64_t nb_packets_per_stream;
3314
3315 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3316 tmp_output.max_size);
3317 if (nb_packets_per_stream < 0) {
3318 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3319 goto error;
3320 }
3321 ret = record_kernel_snapshot(ksess, &tmp_output, session,
3322 wait, nb_packets_per_stream);
3323 if (ret != LTTNG_OK) {
3324 goto error;
3325 }
3326 snapshot_success = 1;
3327 } else {
3328 struct snapshot_output *sout;
3329 struct lttng_ht_iter iter;
3330
3331 rcu_read_lock();
3332 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3333 &iter.iter, sout, node.node) {
3334 int64_t nb_packets_per_stream;
3335
3336 /*
3337 * Make a local copy of the output and assign the possible
3338 * temporary value given by the caller.
3339 */
3340 memset(&tmp_output, 0, sizeof(tmp_output));
3341 memcpy(&tmp_output, sout, sizeof(tmp_output));
3342
3343 if (output->max_size != (uint64_t) -1ULL) {
3344 tmp_output.max_size = output->max_size;
3345 }
3346
3347 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3348 tmp_output.max_size);
3349 if (nb_packets_per_stream < 0) {
3350 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3351 goto error;
3352 }
3353
3354 /* Use temporary name. */
3355 if (*output->name != '\0') {
3356 strncpy(tmp_output.name, output->name,
3357 sizeof(tmp_output.name));
3358 }
3359
3360 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3361
3362 ret = record_kernel_snapshot(ksess, &tmp_output,
3363 session, wait, nb_packets_per_stream);
3364 if (ret != LTTNG_OK) {
3365 rcu_read_unlock();
3366 goto error;
3367 }
3368 snapshot_success = 1;
3369 }
3370 rcu_read_unlock();
3371 }
3372 }
3373
3374 if (session->ust_session) {
3375 struct ltt_ust_session *usess = session->ust_session;
3376
3377 if (use_tmp_output) {
3378 int64_t nb_packets_per_stream;
3379
3380 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3381 tmp_output.max_size);
3382 if (nb_packets_per_stream < 0) {
3383 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3384 goto error;
3385 }
3386 ret = record_ust_snapshot(usess, &tmp_output, session,
3387 wait, nb_packets_per_stream);
3388 if (ret != LTTNG_OK) {
3389 goto error;
3390 }
3391 snapshot_success = 1;
3392 } else {
3393 struct snapshot_output *sout;
3394 struct lttng_ht_iter iter;
3395
3396 rcu_read_lock();
3397 cds_lfht_for_each_entry(session->snapshot.output_ht->ht,
3398 &iter.iter, sout, node.node) {
3399 int64_t nb_packets_per_stream;
3400
3401 /*
3402 * Make a local copy of the output and assign the possible
3403 * temporary value given by the caller.
3404 */
3405 memset(&tmp_output, 0, sizeof(tmp_output));
3406 memcpy(&tmp_output, sout, sizeof(tmp_output));
3407
3408 if (output->max_size != (uint64_t) -1ULL) {
3409 tmp_output.max_size = output->max_size;
3410 }
3411
3412 nb_packets_per_stream = get_session_nb_packets_per_stream(session,
3413 tmp_output.max_size);
3414 if (nb_packets_per_stream < 0) {
3415 ret = LTTNG_ERR_MAX_SIZE_INVALID;
3416 rcu_read_unlock();
3417 goto error;
3418 }
3419
3420 /* Use temporary name. */
3421 if (*output->name != '\0') {
3422 strncpy(tmp_output.name, output->name,
3423 sizeof(tmp_output.name));
3424 }
3425
3426 tmp_output.nb_snapshot = session->snapshot.nb_snapshot;
3427
3428 ret = record_ust_snapshot(usess, &tmp_output, session,
3429 wait, nb_packets_per_stream);
3430 if (ret != LTTNG_OK) {
3431 rcu_read_unlock();
3432 goto error;
3433 }
3434 snapshot_success = 1;
3435 }
3436 rcu_read_unlock();
3437 }
3438 }
3439
3440 if (snapshot_success) {
3441 session->snapshot.nb_snapshot++;
3442 } else {
3443 ret = LTTNG_ERR_SNAPSHOT_FAIL;
3444 }
3445
3446 error:
3447 return ret;
3448 }
3449
3450 /*
3451 * Command LTTNG_SET_SESSION_SHM_PATH processed by the client thread.
3452 */
3453 int cmd_set_session_shm_path(struct ltt_session *session,
3454 const char *shm_path)
3455 {
3456 /* Safety net */
3457 assert(session);
3458
3459 /*
3460 * Can only set shm path before session is started.
3461 */
3462 if (session->has_been_started) {
3463 return LTTNG_ERR_SESSION_STARTED;
3464 }
3465
3466 strncpy(session->shm_path, shm_path,
3467 sizeof(session->shm_path));
3468 session->shm_path[sizeof(session->shm_path) - 1] = '\0';
3469
3470 return 0;
3471 }
3472
3473 /*
3474 * Init command subsystem.
3475 */
3476 void cmd_init(void)
3477 {
3478 /*
3479 * Set network sequence index to 1 for streams to match a relayd
3480 * socket on the consumer side.
3481 */
3482 pthread_mutex_lock(&relayd_net_seq_idx_lock);
3483 relayd_net_seq_idx = 1;
3484 pthread_mutex_unlock(&relayd_net_seq_idx_lock);
3485
3486 DBG("Command subsystem initialized");
3487 }
LTTng 2.0 tools and control repository
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