Rename ltt-sessiond to lttng-sessiond
[lttng-tools.git] / lttng-sessiond / main.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the Free
7 * Software Foundation; only version 2 of the License.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
16 * Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18
19 #define _GNU_SOURCE
20 #include <fcntl.h>
21 #include <getopt.h>
22 #include <grp.h>
23 #include <limits.h>
24 #include <pthread.h>
25 #include <semaphore.h>
26 #include <signal.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <sys/mman.h>
31 #include <sys/mount.h>
32 #include <sys/resource.h>
33 #include <sys/socket.h>
34 #include <sys/stat.h>
35 #include <sys/types.h>
36 #include <sys/wait.h>
37 #include <urcu/futex.h>
38 #include <unistd.h>
39 #include <config.h>
40
41 #include <lttng-consumerd.h>
42 #include <lttng-sessiond-comm.h>
43 #include <lttng/lttng-consumer.h>
44
45 #include <lttngerr.h>
46
47 #include "channel.h"
48 #include "compat/poll.h"
49 #include "context.h"
50 #include "event.h"
51 #include "futex.h"
52 #include "hashtable.h"
53 #include "kernel-ctl.h"
54 #include "lttng-sessiond.h"
55 #include "shm.h"
56 #include "ust-app.h"
57 #include "ust-ctl.h"
58 #include "utils.h"
59
60 struct consumer_data {
61 enum lttng_consumer_type type;
62
63 pthread_t thread; /* Worker thread interacting with the consumer */
64 sem_t sem;
65
66 /* Mutex to control consumerd pid assignation */
67 pthread_mutex_t pid_mutex;
68 pid_t pid;
69
70 int err_sock;
71 int cmd_sock;
72
73 /* consumer error and command Unix socket path */
74 char err_unix_sock_path[PATH_MAX];
75 char cmd_unix_sock_path[PATH_MAX];
76 };
77
78 /* Const values */
79 const char default_home_dir[] = DEFAULT_HOME_DIR;
80 const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
81 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
82 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
83
84 /* Variables */
85 int opt_verbose; /* Not static for lttngerr.h */
86 int opt_verbose_consumer; /* Not static for lttngerr.h */
87 int opt_quiet; /* Not static for lttngerr.h */
88
89 const char *progname;
90 const char *opt_tracing_group;
91 static int opt_sig_parent;
92 static int opt_daemon;
93 static int is_root; /* Set to 1 if the daemon is running as root */
94 static pid_t ppid; /* Parent PID for --sig-parent option */
95
96 /* Consumer daemon specific control data */
97 static struct consumer_data kconsumer_data = {
98 .type = LTTNG_CONSUMER_KERNEL,
99 };
100 static struct consumer_data ustconsumer_data = {
101 .type = LTTNG_CONSUMER_UST,
102 };
103
104 static int dispatch_thread_exit;
105
106 /* Global application Unix socket path */
107 static char apps_unix_sock_path[PATH_MAX];
108 /* Global client Unix socket path */
109 static char client_unix_sock_path[PATH_MAX];
110 /* global wait shm path for UST */
111 static char wait_shm_path[PATH_MAX];
112
113 /* Sockets and FDs */
114 static int client_sock;
115 static int apps_sock;
116 static int kernel_tracer_fd;
117 static int kernel_poll_pipe[2];
118
119 /*
120 * Quit pipe for all threads. This permits a single cancellation point
121 * for all threads when receiving an event on the pipe.
122 */
123 static int thread_quit_pipe[2];
124
125 /*
126 * This pipe is used to inform the thread managing application communication
127 * that a command is queued and ready to be processed.
128 */
129 static int apps_cmd_pipe[2];
130
131 /* Pthread, Mutexes and Semaphores */
132 static pthread_t apps_thread;
133 static pthread_t reg_apps_thread;
134 static pthread_t client_thread;
135 static pthread_t kernel_thread;
136 static pthread_t dispatch_thread;
137
138
139 /*
140 * UST registration command queue. This queue is tied with a futex and uses a N
141 * wakers / 1 waiter implemented and detailed in futex.c/.h
142 *
143 * The thread_manage_apps and thread_dispatch_ust_registration interact with
144 * this queue and the wait/wake scheme.
145 */
146 static struct ust_cmd_queue ust_cmd_queue;
147
148 /*
149 * Pointer initialized before thread creation.
150 *
151 * This points to the tracing session list containing the session count and a
152 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
153 * MUST NOT be taken if you call a public function in session.c.
154 *
155 * The lock is nested inside the structure: session_list_ptr->lock. Please use
156 * session_lock_list and session_unlock_list for lock acquisition.
157 */
158 static struct ltt_session_list *session_list_ptr;
159
160 /*
161 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
162 */
163 static int create_thread_poll_set(struct lttng_poll_event *events,
164 unsigned int size)
165 {
166 int ret;
167
168 if (events == NULL || size == 0) {
169 ret = -1;
170 goto error;
171 }
172
173 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
174 if (ret < 0) {
175 goto error;
176 }
177
178 /* Add quit pipe */
179 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
180 if (ret < 0) {
181 goto error;
182 }
183
184 return 0;
185
186 error:
187 return ret;
188 }
189
190 /*
191 * Check if the thread quit pipe was triggered.
192 *
193 * Return 1 if it was triggered else 0;
194 */
195 static int check_thread_quit_pipe(int fd, uint32_t events)
196 {
197 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
198 return 1;
199 }
200
201 return 0;
202 }
203
204 /*
205 * Remove modules in reverse load order.
206 */
207 static int modprobe_remove_kernel_modules(void)
208 {
209 int ret = 0, i;
210 char modprobe[256];
211
212 for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
213 ret = snprintf(modprobe, sizeof(modprobe),
214 "/sbin/modprobe -r -q %s",
215 kernel_modules_list[i].name);
216 if (ret < 0) {
217 perror("snprintf modprobe -r");
218 goto error;
219 }
220 modprobe[sizeof(modprobe) - 1] = '\0';
221 ret = system(modprobe);
222 if (ret == -1) {
223 ERR("Unable to launch modprobe -r for module %s",
224 kernel_modules_list[i].name);
225 } else if (kernel_modules_list[i].required
226 && WEXITSTATUS(ret) != 0) {
227 ERR("Unable to remove module %s",
228 kernel_modules_list[i].name);
229 } else {
230 DBG("Modprobe removal successful %s",
231 kernel_modules_list[i].name);
232 }
233 }
234
235 error:
236 return ret;
237 }
238
239 /*
240 * Return group ID of the tracing group or -1 if not found.
241 */
242 static gid_t allowed_group(void)
243 {
244 struct group *grp;
245
246 if (opt_tracing_group) {
247 grp = getgrnam(opt_tracing_group);
248 } else {
249 grp = getgrnam(default_tracing_group);
250 }
251 if (!grp) {
252 return -1;
253 } else {
254 return grp->gr_gid;
255 }
256 }
257
258 /*
259 * Init thread quit pipe.
260 *
261 * Return -1 on error or 0 if all pipes are created.
262 */
263 static int init_thread_quit_pipe(void)
264 {
265 int ret;
266
267 ret = pipe2(thread_quit_pipe, O_CLOEXEC);
268 if (ret < 0) {
269 perror("thread quit pipe");
270 goto error;
271 }
272
273 error:
274 return ret;
275 }
276
277 /*
278 * Complete teardown of a kernel session. This free all data structure related
279 * to a kernel session and update counter.
280 */
281 static void teardown_kernel_session(struct ltt_session *session)
282 {
283 if (session->kernel_session != NULL) {
284 DBG("Tearing down kernel session");
285
286 /*
287 * If a custom kernel consumer was registered, close the socket before
288 * tearing down the complete kernel session structure
289 */
290 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
291 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
292 }
293
294 trace_kernel_destroy_session(session->kernel_session);
295 /* Extra precaution */
296 session->kernel_session = NULL;
297 }
298 }
299
300 /*
301 * Complete teardown of all UST sessions. This will free everything on his path
302 * and destroy the core essence of all ust sessions :)
303 */
304 static void teardown_ust_session(struct ltt_session *session)
305 {
306 DBG("Tearing down UST session(s)");
307
308 trace_ust_destroy_session(session->ust_session);
309 }
310
311 /*
312 * Stop all threads by closing the thread quit pipe.
313 */
314 static void stop_threads(void)
315 {
316 int ret;
317
318 /* Stopping all threads */
319 DBG("Terminating all threads");
320 ret = notify_thread_pipe(thread_quit_pipe[1]);
321 if (ret < 0) {
322 ERR("write error on thread quit pipe");
323 }
324
325 /* Dispatch thread */
326 dispatch_thread_exit = 1;
327 futex_nto1_wake(&ust_cmd_queue.futex);
328 }
329
330 /*
331 * Cleanup the daemon
332 */
333 static void cleanup(void)
334 {
335 int ret;
336 char *cmd;
337 struct ltt_session *sess, *stmp;
338
339 DBG("Cleaning up");
340
341 /* <fun> */
342 MSG("%c[%d;%dm*** assert failed *** ==> %c[%dm%c[%d;%dm"
343 "Matthew, BEET driven development works!%c[%dm",
344 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
345 /* </fun> */
346
347 if (is_root) {
348 DBG("Removing %s directory", LTTNG_RUNDIR);
349 ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
350 if (ret < 0) {
351 ERR("asprintf failed. Something is really wrong!");
352 }
353
354 /* Remove lttng run directory */
355 ret = system(cmd);
356 if (ret < 0) {
357 ERR("Unable to clean " LTTNG_RUNDIR);
358 }
359 }
360
361 DBG("Cleaning up all session");
362
363 /* Destroy session list mutex */
364 if (session_list_ptr != NULL) {
365 pthread_mutex_destroy(&session_list_ptr->lock);
366
367 /* Cleanup ALL session */
368 cds_list_for_each_entry_safe(sess, stmp,
369 &session_list_ptr->head, list) {
370 teardown_kernel_session(sess);
371 teardown_ust_session(sess);
372 free(sess);
373 }
374 }
375
376 DBG("Closing all UST sockets");
377 ust_app_clean_list();
378
379 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
380
381 DBG("Closing kernel fd");
382 close(kernel_tracer_fd);
383
384 if (is_root) {
385 DBG("Unloading kernel modules");
386 modprobe_remove_kernel_modules();
387 }
388
389 close(thread_quit_pipe[0]);
390 close(thread_quit_pipe[1]);
391 }
392
393 /*
394 * Send data on a unix socket using the liblttsessiondcomm API.
395 *
396 * Return lttcomm error code.
397 */
398 static int send_unix_sock(int sock, void *buf, size_t len)
399 {
400 /* Check valid length */
401 if (len <= 0) {
402 return -1;
403 }
404
405 return lttcomm_send_unix_sock(sock, buf, len);
406 }
407
408 /*
409 * Free memory of a command context structure.
410 */
411 static void clean_command_ctx(struct command_ctx **cmd_ctx)
412 {
413 DBG("Clean command context structure");
414 if (*cmd_ctx) {
415 if ((*cmd_ctx)->llm) {
416 free((*cmd_ctx)->llm);
417 }
418 if ((*cmd_ctx)->lsm) {
419 free((*cmd_ctx)->lsm);
420 }
421 free(*cmd_ctx);
422 *cmd_ctx = NULL;
423 }
424 }
425
426 /*
427 * Send all stream fds of kernel channel to the consumer.
428 */
429 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
430 int sock, struct ltt_kernel_channel *channel)
431 {
432 int ret;
433 struct ltt_kernel_stream *stream;
434 struct lttcomm_consumer_msg lkm;
435
436 DBG("Sending streams of channel %s to kernel consumer",
437 channel->channel->name);
438
439 /* Send channel */
440 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
441 lkm.u.channel.channel_key = channel->fd;
442 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
443 lkm.u.channel.mmap_len = 0; /* for kernel */
444 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
445 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
446 if (ret < 0) {
447 perror("send consumer channel");
448 goto error;
449 }
450
451 /* Send streams */
452 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
453 if (!stream->fd) {
454 continue;
455 }
456 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
457 lkm.u.stream.channel_key = channel->fd;
458 lkm.u.stream.stream_key = stream->fd;
459 lkm.u.stream.state = stream->state;
460 lkm.u.stream.output = channel->channel->attr.output;
461 lkm.u.stream.mmap_len = 0; /* for kernel */
462 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
463 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
464 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
465 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
466 if (ret < 0) {
467 perror("send consumer stream");
468 goto error;
469 }
470 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
471 if (ret < 0) {
472 perror("send consumer stream ancillary data");
473 goto error;
474 }
475 }
476
477 DBG("consumer channel streams sent");
478
479 return 0;
480
481 error:
482 return ret;
483 }
484
485 /*
486 * Send all stream fds of the kernel session to the consumer.
487 */
488 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
489 struct ltt_kernel_session *session)
490 {
491 int ret;
492 struct ltt_kernel_channel *chan;
493 struct lttcomm_consumer_msg lkm;
494 int sock = session->consumer_fd;
495
496 DBG("Sending metadata stream fd");
497
498 /* Extra protection. It's NOT supposed to be set to 0 at this point */
499 if (session->consumer_fd == 0) {
500 session->consumer_fd = consumer_data->cmd_sock;
501 }
502
503 if (session->metadata_stream_fd != 0) {
504 /* Send metadata channel fd */
505 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
506 lkm.u.channel.channel_key = session->metadata->fd;
507 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
508 lkm.u.channel.mmap_len = 0; /* for kernel */
509 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
510 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
511 if (ret < 0) {
512 perror("send consumer channel");
513 goto error;
514 }
515
516 /* Send metadata stream fd */
517 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
518 lkm.u.stream.channel_key = session->metadata->fd;
519 lkm.u.stream.stream_key = session->metadata_stream_fd;
520 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
521 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
522 lkm.u.stream.mmap_len = 0; /* for kernel */
523 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
524 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
525 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
526 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
527 if (ret < 0) {
528 perror("send consumer stream");
529 goto error;
530 }
531 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
532 if (ret < 0) {
533 perror("send consumer stream");
534 goto error;
535 }
536 }
537
538 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
539 ret = send_kconsumer_channel_streams(consumer_data, sock, chan);
540 if (ret < 0) {
541 goto error;
542 }
543 }
544
545 DBG("consumer fds (metadata and channel streams) sent");
546
547 return 0;
548
549 error:
550 return ret;
551 }
552
553 /*
554 * Notify UST applications using the shm mmap futex.
555 */
556 static int notify_ust_apps(int active)
557 {
558 char *wait_shm_mmap;
559
560 DBG("Notifying applications of session daemon state: %d", active);
561
562 /* See shm.c for this call implying mmap, shm and futex calls */
563 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
564 if (wait_shm_mmap == NULL) {
565 goto error;
566 }
567
568 /* Wake waiting process */
569 futex_wait_update((int32_t *) wait_shm_mmap, active);
570
571 /* Apps notified successfully */
572 return 0;
573
574 error:
575 return -1;
576 }
577
578 /*
579 * Setup the outgoing data buffer for the response (llm) by allocating the
580 * right amount of memory and copying the original information from the lsm
581 * structure.
582 *
583 * Return total size of the buffer pointed by buf.
584 */
585 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
586 {
587 int ret, buf_size;
588
589 buf_size = size;
590
591 cmd_ctx->llm = malloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
592 if (cmd_ctx->llm == NULL) {
593 perror("malloc");
594 ret = -ENOMEM;
595 goto error;
596 }
597
598 /* Copy common data */
599 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
600 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
601
602 cmd_ctx->llm->data_size = size;
603 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
604
605 return buf_size;
606
607 error:
608 return ret;
609 }
610
611 /*
612 * Update the kernel poll set of all channel fd available over all tracing
613 * session. Add the wakeup pipe at the end of the set.
614 */
615 static int update_kernel_poll(struct lttng_poll_event *events)
616 {
617 int ret;
618 struct ltt_session *session;
619 struct ltt_kernel_channel *channel;
620
621 DBG("Updating kernel poll set");
622
623 session_lock_list();
624 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
625 session_lock(session);
626 if (session->kernel_session == NULL) {
627 session_unlock(session);
628 continue;
629 }
630
631 cds_list_for_each_entry(channel,
632 &session->kernel_session->channel_list.head, list) {
633 /* Add channel fd to the kernel poll set */
634 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
635 if (ret < 0) {
636 session_unlock(session);
637 goto error;
638 }
639 DBG("Channel fd %d added to kernel set", channel->fd);
640 }
641 session_unlock(session);
642 }
643 session_unlock_list();
644
645 return 0;
646
647 error:
648 session_unlock_list();
649 return -1;
650 }
651
652 /*
653 * Find the channel fd from 'fd' over all tracing session. When found, check
654 * for new channel stream and send those stream fds to the kernel consumer.
655 *
656 * Useful for CPU hotplug feature.
657 */
658 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
659 {
660 int ret = 0;
661 struct ltt_session *session;
662 struct ltt_kernel_channel *channel;
663
664 DBG("Updating kernel streams for channel fd %d", fd);
665
666 session_lock_list();
667 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
668 session_lock(session);
669 if (session->kernel_session == NULL) {
670 session_unlock(session);
671 continue;
672 }
673
674 /* This is not suppose to be 0 but this is an extra security check */
675 if (session->kernel_session->consumer_fd == 0) {
676 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
677 }
678
679 cds_list_for_each_entry(channel,
680 &session->kernel_session->channel_list.head, list) {
681 if (channel->fd == fd) {
682 DBG("Channel found, updating kernel streams");
683 ret = kernel_open_channel_stream(channel);
684 if (ret < 0) {
685 goto error;
686 }
687
688 /*
689 * Have we already sent fds to the consumer? If yes, it means
690 * that tracing is started so it is safe to send our updated
691 * stream fds.
692 */
693 if (session->kernel_session->consumer_fds_sent == 1) {
694 ret = send_kconsumer_channel_streams(consumer_data,
695 session->kernel_session->consumer_fd, channel);
696 if (ret < 0) {
697 goto error;
698 }
699 }
700 goto error;
701 }
702 }
703 session_unlock(session);
704 }
705 session_unlock_list();
706 return ret;
707
708 error:
709 session_unlock(session);
710 session_unlock_list();
711 return ret;
712 }
713
714 /*
715 * This thread manage event coming from the kernel.
716 *
717 * Features supported in this thread:
718 * -) CPU Hotplug
719 */
720 static void *thread_manage_kernel(void *data)
721 {
722 int ret, i, pollfd, update_poll_flag = 1;
723 uint32_t revents, nb_fd;
724 char tmp;
725 struct lttng_poll_event events;
726
727 DBG("Thread manage kernel started");
728
729 ret = create_thread_poll_set(&events, 2);
730 if (ret < 0) {
731 goto error;
732 }
733
734 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
735 if (ret < 0) {
736 goto error;
737 }
738
739 while (1) {
740 if (update_poll_flag == 1) {
741 /*
742 * Reset number of fd in the poll set. Always 2 since there is the thread
743 * quit pipe and the kernel pipe.
744 */
745 events.nb_fd = 2;
746
747 ret = update_kernel_poll(&events);
748 if (ret < 0) {
749 goto error;
750 }
751 update_poll_flag = 0;
752 }
753
754 nb_fd = LTTNG_POLL_GETNB(&events);
755
756 DBG("Thread kernel polling on %d fds", nb_fd);
757
758 /* Zeroed the poll events */
759 lttng_poll_reset(&events);
760
761 /* Poll infinite value of time */
762 ret = lttng_poll_wait(&events, -1);
763 if (ret < 0) {
764 goto error;
765 } else if (ret == 0) {
766 /* Should not happen since timeout is infinite */
767 ERR("Return value of poll is 0 with an infinite timeout.\n"
768 "This should not have happened! Continuing...");
769 continue;
770 }
771
772 for (i = 0; i < nb_fd; i++) {
773 /* Fetch once the poll data */
774 revents = LTTNG_POLL_GETEV(&events, i);
775 pollfd = LTTNG_POLL_GETFD(&events, i);
776
777 /* Thread quit pipe has been closed. Killing thread. */
778 ret = check_thread_quit_pipe(pollfd, revents);
779 if (ret) {
780 goto error;
781 }
782
783 /* Check for data on kernel pipe */
784 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
785 ret = read(kernel_poll_pipe[0], &tmp, 1);
786 update_poll_flag = 1;
787 continue;
788 } else {
789 /*
790 * New CPU detected by the kernel. Adding kernel stream to
791 * kernel session and updating the kernel consumer
792 */
793 if (revents & LPOLLIN) {
794 ret = update_kernel_stream(&kconsumer_data, pollfd);
795 if (ret < 0) {
796 continue;
797 }
798 break;
799 /*
800 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
801 * and unregister kernel stream at this point.
802 */
803 }
804 }
805 }
806 }
807
808 error:
809 DBG("Kernel thread dying");
810 close(kernel_poll_pipe[0]);
811 close(kernel_poll_pipe[1]);
812
813 lttng_poll_clean(&events);
814
815 return NULL;
816 }
817
818 /*
819 * This thread manage the consumer error sent back to the session daemon.
820 */
821 static void *thread_manage_consumer(void *data)
822 {
823 int sock = 0, i, ret, pollfd;
824 uint32_t revents, nb_fd;
825 enum lttcomm_return_code code;
826 struct lttng_poll_event events;
827 struct consumer_data *consumer_data = data;
828
829 DBG("[thread] Manage consumer started");
830
831 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
832 if (ret < 0) {
833 goto error;
834 }
835
836 /*
837 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
838 * Nothing more will be added to this poll set.
839 */
840 ret = create_thread_poll_set(&events, 2);
841 if (ret < 0) {
842 goto error;
843 }
844
845 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
846 if (ret < 0) {
847 goto error;
848 }
849
850 nb_fd = LTTNG_POLL_GETNB(&events);
851
852 /* Inifinite blocking call, waiting for transmission */
853 ret = lttng_poll_wait(&events, -1);
854 if (ret < 0) {
855 goto error;
856 }
857
858 for (i = 0; i < nb_fd; i++) {
859 /* Fetch once the poll data */
860 revents = LTTNG_POLL_GETEV(&events, i);
861 pollfd = LTTNG_POLL_GETFD(&events, i);
862
863 /* Thread quit pipe has been closed. Killing thread. */
864 ret = check_thread_quit_pipe(pollfd, revents);
865 if (ret) {
866 goto error;
867 }
868
869 /* Event on the registration socket */
870 if (pollfd == consumer_data->err_sock) {
871 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
872 ERR("consumer err socket poll error");
873 goto error;
874 }
875 }
876 }
877
878 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
879 if (sock < 0) {
880 goto error;
881 }
882
883 DBG2("Receiving code from consumer err_sock");
884
885 /* Getting status code from kconsumerd */
886 ret = lttcomm_recv_unix_sock(sock, &code,
887 sizeof(enum lttcomm_return_code));
888 if (ret <= 0) {
889 goto error;
890 }
891
892 if (code == CONSUMERD_COMMAND_SOCK_READY) {
893 consumer_data->cmd_sock =
894 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
895 if (consumer_data->cmd_sock < 0) {
896 sem_post(&consumer_data->sem);
897 PERROR("consumer connect");
898 goto error;
899 }
900 /* Signal condition to tell that the kconsumerd is ready */
901 sem_post(&consumer_data->sem);
902 DBG("consumer command socket ready");
903 } else {
904 ERR("consumer error when waiting for SOCK_READY : %s",
905 lttcomm_get_readable_code(-code));
906 goto error;
907 }
908
909 /* Remove the kconsumerd error sock since we've established a connexion */
910 ret = lttng_poll_del(&events, consumer_data->err_sock);
911 if (ret < 0) {
912 goto error;
913 }
914
915 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
916 if (ret < 0) {
917 goto error;
918 }
919
920 /* Update number of fd */
921 nb_fd = LTTNG_POLL_GETNB(&events);
922
923 /* Inifinite blocking call, waiting for transmission */
924 ret = lttng_poll_wait(&events, -1);
925 if (ret < 0) {
926 goto error;
927 }
928
929 for (i = 0; i < nb_fd; i++) {
930 /* Fetch once the poll data */
931 revents = LTTNG_POLL_GETEV(&events, i);
932 pollfd = LTTNG_POLL_GETFD(&events, i);
933
934 /* Thread quit pipe has been closed. Killing thread. */
935 ret = check_thread_quit_pipe(pollfd, revents);
936 if (ret) {
937 goto error;
938 }
939
940 /* Event on the kconsumerd socket */
941 if (pollfd == sock) {
942 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
943 ERR("consumer err socket second poll error");
944 goto error;
945 }
946 }
947 }
948
949 /* Wait for any kconsumerd error */
950 ret = lttcomm_recv_unix_sock(sock, &code,
951 sizeof(enum lttcomm_return_code));
952 if (ret <= 0) {
953 ERR("consumer closed the command socket");
954 goto error;
955 }
956
957 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
958
959 error:
960 DBG("consumer thread dying");
961 close(consumer_data->err_sock);
962 close(consumer_data->cmd_sock);
963 close(sock);
964
965 unlink(consumer_data->err_unix_sock_path);
966 unlink(consumer_data->cmd_unix_sock_path);
967 consumer_data->pid = 0;
968
969 lttng_poll_clean(&events);
970
971 return NULL;
972 }
973
974 /*
975 * This thread manage application communication.
976 */
977 static void *thread_manage_apps(void *data)
978 {
979 int i, ret, pollfd;
980 uint32_t revents, nb_fd;
981 struct ust_command ust_cmd;
982 struct lttng_poll_event events;
983
984 DBG("[thread] Manage application started");
985
986 rcu_register_thread();
987 rcu_thread_online();
988
989 ret = create_thread_poll_set(&events, 2);
990 if (ret < 0) {
991 goto error;
992 }
993
994 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
995 if (ret < 0) {
996 goto error;
997 }
998
999 while (1) {
1000 /* Zeroed the events structure */
1001 lttng_poll_reset(&events);
1002
1003 nb_fd = LTTNG_POLL_GETNB(&events);
1004
1005 DBG("Apps thread polling on %d fds", nb_fd);
1006
1007 /* Inifinite blocking call, waiting for transmission */
1008 ret = lttng_poll_wait(&events, -1);
1009 if (ret < 0) {
1010 goto error;
1011 }
1012
1013 for (i = 0; i < nb_fd; i++) {
1014 /* Fetch once the poll data */
1015 revents = LTTNG_POLL_GETEV(&events, i);
1016 pollfd = LTTNG_POLL_GETFD(&events, i);
1017
1018 /* Thread quit pipe has been closed. Killing thread. */
1019 ret = check_thread_quit_pipe(pollfd, revents);
1020 if (ret) {
1021 goto error;
1022 }
1023
1024 /* Inspect the apps cmd pipe */
1025 if (pollfd == apps_cmd_pipe[0]) {
1026 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1027 ERR("Apps command pipe error");
1028 goto error;
1029 } else if (revents & LPOLLIN) {
1030 /* Empty pipe */
1031 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1032 if (ret < 0 || ret < sizeof(ust_cmd)) {
1033 perror("read apps cmd pipe");
1034 goto error;
1035 }
1036
1037 /* Register applicaton to the session daemon */
1038 ret = ust_app_register(&ust_cmd.reg_msg,
1039 ust_cmd.sock);
1040 if (ret < 0) {
1041 /* Only critical ENOMEM error can be returned here */
1042 goto error;
1043 }
1044
1045 ret = ustctl_register_done(ust_cmd.sock);
1046 if (ret < 0) {
1047 /*
1048 * If the registration is not possible, we simply
1049 * unregister the apps and continue
1050 */
1051 ust_app_unregister(ust_cmd.sock);
1052 } else {
1053 /*
1054 * We just need here to monitor the close of the UST
1055 * socket and poll set monitor those by default.
1056 */
1057 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1058 if (ret < 0) {
1059 goto error;
1060 }
1061
1062 DBG("Apps with sock %d added to poll set",
1063 ust_cmd.sock);
1064 }
1065 break;
1066 }
1067 } else {
1068 /*
1069 * At this point, we know that a registered application made
1070 * the event at poll_wait.
1071 */
1072 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1073 /* Removing from the poll set */
1074 ret = lttng_poll_del(&events, pollfd);
1075 if (ret < 0) {
1076 goto error;
1077 }
1078
1079 /* Socket closed */
1080 ust_app_unregister(pollfd);
1081 break;
1082 }
1083 }
1084 }
1085 }
1086
1087 error:
1088 DBG("Application communication apps dying");
1089 close(apps_cmd_pipe[0]);
1090 close(apps_cmd_pipe[1]);
1091
1092 lttng_poll_clean(&events);
1093
1094 rcu_thread_offline();
1095 rcu_unregister_thread();
1096 return NULL;
1097 }
1098
1099 /*
1100 * Dispatch request from the registration threads to the application
1101 * communication thread.
1102 */
1103 static void *thread_dispatch_ust_registration(void *data)
1104 {
1105 int ret;
1106 struct cds_wfq_node *node;
1107 struct ust_command *ust_cmd = NULL;
1108
1109 DBG("[thread] Dispatch UST command started");
1110
1111 while (!dispatch_thread_exit) {
1112 /* Atomically prepare the queue futex */
1113 futex_nto1_prepare(&ust_cmd_queue.futex);
1114
1115 do {
1116 /* Dequeue command for registration */
1117 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1118 if (node == NULL) {
1119 DBG("Woken up but nothing in the UST command queue");
1120 /* Continue thread execution */
1121 break;
1122 }
1123
1124 ust_cmd = caa_container_of(node, struct ust_command, node);
1125
1126 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1127 " gid:%d sock:%d name:%s (version %d.%d)",
1128 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1129 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1130 ust_cmd->sock, ust_cmd->reg_msg.name,
1131 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1132 /*
1133 * Inform apps thread of the new application registration. This
1134 * call is blocking so we can be assured that the data will be read
1135 * at some point in time or wait to the end of the world :)
1136 */
1137 ret = write(apps_cmd_pipe[1], ust_cmd,
1138 sizeof(struct ust_command));
1139 if (ret < 0) {
1140 perror("write apps cmd pipe");
1141 if (errno == EBADF) {
1142 /*
1143 * We can't inform the application thread to process
1144 * registration. We will exit or else application
1145 * registration will not occur and tracing will never
1146 * start.
1147 */
1148 goto error;
1149 }
1150 }
1151 free(ust_cmd);
1152 } while (node != NULL);
1153
1154 /* Futex wait on queue. Blocking call on futex() */
1155 futex_nto1_wait(&ust_cmd_queue.futex);
1156 }
1157
1158 error:
1159 DBG("Dispatch thread dying");
1160 return NULL;
1161 }
1162
1163 /*
1164 * This thread manage application registration.
1165 */
1166 static void *thread_registration_apps(void *data)
1167 {
1168 int sock = 0, i, ret, pollfd;
1169 uint32_t revents, nb_fd;
1170 struct lttng_poll_event events;
1171 /*
1172 * Get allocated in this thread, enqueued to a global queue, dequeued and
1173 * freed in the manage apps thread.
1174 */
1175 struct ust_command *ust_cmd = NULL;
1176
1177 DBG("[thread] Manage application registration started");
1178
1179 ret = lttcomm_listen_unix_sock(apps_sock);
1180 if (ret < 0) {
1181 goto error;
1182 }
1183
1184 /*
1185 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1186 * more will be added to this poll set.
1187 */
1188 ret = create_thread_poll_set(&events, 2);
1189 if (ret < 0) {
1190 goto error;
1191 }
1192
1193 /* Add the application registration socket */
1194 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1195 if (ret < 0) {
1196 goto error;
1197 }
1198
1199 /* Notify all applications to register */
1200 ret = notify_ust_apps(1);
1201 if (ret < 0) {
1202 ERR("Failed to notify applications or create the wait shared memory.\n"
1203 "Execution continues but there might be problem for already\n"
1204 "running applications that wishes to register.");
1205 }
1206
1207 while (1) {
1208 DBG("Accepting application registration");
1209
1210 nb_fd = LTTNG_POLL_GETNB(&events);
1211
1212 /* Inifinite blocking call, waiting for transmission */
1213 ret = lttng_poll_wait(&events, -1);
1214 if (ret < 0) {
1215 goto error;
1216 }
1217
1218 for (i = 0; i < nb_fd; i++) {
1219 /* Fetch once the poll data */
1220 revents = LTTNG_POLL_GETEV(&events, i);
1221 pollfd = LTTNG_POLL_GETFD(&events, i);
1222
1223 /* Thread quit pipe has been closed. Killing thread. */
1224 ret = check_thread_quit_pipe(pollfd, revents);
1225 if (ret) {
1226 goto error;
1227 }
1228
1229 /* Event on the registration socket */
1230 if (pollfd == apps_sock) {
1231 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1232 ERR("Register apps socket poll error");
1233 goto error;
1234 } else if (revents & LPOLLIN) {
1235 sock = lttcomm_accept_unix_sock(apps_sock);
1236 if (sock < 0) {
1237 goto error;
1238 }
1239
1240 /* Create UST registration command for enqueuing */
1241 ust_cmd = malloc(sizeof(struct ust_command));
1242 if (ust_cmd == NULL) {
1243 perror("ust command malloc");
1244 goto error;
1245 }
1246
1247 /*
1248 * Using message-based transmissions to ensure we don't
1249 * have to deal with partially received messages.
1250 */
1251 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1252 sizeof(struct ust_register_msg));
1253 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1254 if (ret < 0) {
1255 perror("lttcomm_recv_unix_sock register apps");
1256 } else {
1257 ERR("Wrong size received on apps register");
1258 }
1259 free(ust_cmd);
1260 close(sock);
1261 continue;
1262 }
1263
1264 ust_cmd->sock = sock;
1265
1266 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1267 " gid:%d sock:%d name:%s (version %d.%d)",
1268 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1269 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1270 ust_cmd->sock, ust_cmd->reg_msg.name,
1271 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1272
1273 /*
1274 * Lock free enqueue the registration request. The red pill
1275 * has been taken! This apps will be part of the *system*.
1276 */
1277 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1278
1279 /*
1280 * Wake the registration queue futex. Implicit memory
1281 * barrier with the exchange in cds_wfq_enqueue.
1282 */
1283 futex_nto1_wake(&ust_cmd_queue.futex);
1284 }
1285 }
1286 }
1287 }
1288
1289 error:
1290 DBG("UST Registration thread dying");
1291
1292 /* Notify that the registration thread is gone */
1293 notify_ust_apps(0);
1294
1295 close(apps_sock);
1296 close(sock);
1297 unlink(apps_unix_sock_path);
1298
1299 lttng_poll_clean(&events);
1300
1301 return NULL;
1302 }
1303
1304 /*
1305 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1306 * exec or it will fails.
1307 */
1308 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1309 {
1310 int ret;
1311 struct timespec timeout;
1312
1313 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1314 timeout.tv_nsec = 0;
1315
1316 /* Setup semaphore */
1317 ret = sem_init(&consumer_data->sem, 0, 0);
1318 if (ret < 0) {
1319 PERROR("sem_init consumer semaphore");
1320 goto error;
1321 }
1322
1323 ret = pthread_create(&consumer_data->thread, NULL,
1324 thread_manage_consumer, consumer_data);
1325 if (ret != 0) {
1326 PERROR("pthread_create consumer");
1327 ret = -1;
1328 goto error;
1329 }
1330
1331 /* Get time for sem_timedwait absolute timeout */
1332 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1333 if (ret < 0) {
1334 PERROR("clock_gettime spawn consumer");
1335 /* Infinite wait for the kconsumerd thread to be ready */
1336 ret = sem_wait(&consumer_data->sem);
1337 } else {
1338 /* Normal timeout if the gettime was successful */
1339 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1340 ret = sem_timedwait(&consumer_data->sem, &timeout);
1341 }
1342
1343 if (ret < 0) {
1344 if (errno == ETIMEDOUT) {
1345 /*
1346 * Call has timed out so we kill the kconsumerd_thread and return
1347 * an error.
1348 */
1349 ERR("The consumer thread was never ready. Killing it");
1350 ret = pthread_cancel(consumer_data->thread);
1351 if (ret < 0) {
1352 PERROR("pthread_cancel consumer thread");
1353 }
1354 } else {
1355 PERROR("semaphore wait failed consumer thread");
1356 }
1357 goto error;
1358 }
1359
1360 pthread_mutex_lock(&consumer_data->pid_mutex);
1361 if (consumer_data->pid == 0) {
1362 ERR("Kconsumerd did not start");
1363 pthread_mutex_unlock(&consumer_data->pid_mutex);
1364 goto error;
1365 }
1366 pthread_mutex_unlock(&consumer_data->pid_mutex);
1367
1368 return 0;
1369
1370 error:
1371 return ret;
1372 }
1373
1374 /*
1375 * Join consumer thread
1376 */
1377 static int join_consumer_thread(struct consumer_data *consumer_data)
1378 {
1379 void *status;
1380 int ret;
1381
1382 if (consumer_data->pid != 0) {
1383 ret = kill(consumer_data->pid, SIGTERM);
1384 if (ret) {
1385 ERR("Error killing consumer daemon");
1386 return ret;
1387 }
1388 return pthread_join(consumer_data->thread, &status);
1389 } else {
1390 return 0;
1391 }
1392 }
1393
1394 /*
1395 * Fork and exec a consumer daemon (consumerd).
1396 *
1397 * Return pid if successful else -1.
1398 */
1399 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1400 {
1401 int ret;
1402 pid_t pid;
1403 const char *verbosity;
1404
1405 DBG("Spawning consumerd");
1406
1407 pid = fork();
1408 if (pid == 0) {
1409 /*
1410 * Exec consumerd.
1411 */
1412 if (opt_verbose > 1 || opt_verbose_consumer) {
1413 verbosity = "--verbose";
1414 } else {
1415 verbosity = "--quiet";
1416 }
1417 switch (consumer_data->type) {
1418 case LTTNG_CONSUMER_KERNEL:
1419 execl(INSTALL_BIN_PATH "/lttng-consumerd",
1420 "lttng-consumerd", verbosity, "-k", NULL);
1421 break;
1422 case LTTNG_CONSUMER_UST:
1423 execl(INSTALL_BIN_PATH "/lttng-consumerd",
1424 "lttng-consumerd", verbosity, "-u", NULL);
1425 break;
1426 default:
1427 perror("unknown consumer type");
1428 exit(EXIT_FAILURE);
1429 }
1430 if (errno != 0) {
1431 perror("kernel start consumer exec");
1432 }
1433 exit(EXIT_FAILURE);
1434 } else if (pid > 0) {
1435 ret = pid;
1436 } else {
1437 perror("start consumer fork");
1438 ret = -errno;
1439 }
1440 return ret;
1441 }
1442
1443 /*
1444 * Spawn the consumerd daemon and session daemon thread.
1445 */
1446 static int start_consumerd(struct consumer_data *consumer_data)
1447 {
1448 int ret;
1449
1450 pthread_mutex_lock(&consumer_data->pid_mutex);
1451 if (consumer_data->pid != 0) {
1452 pthread_mutex_unlock(&consumer_data->pid_mutex);
1453 goto end;
1454 }
1455
1456 ret = spawn_consumerd(consumer_data);
1457 if (ret < 0) {
1458 ERR("Spawning consumerd failed");
1459 pthread_mutex_unlock(&consumer_data->pid_mutex);
1460 goto error;
1461 }
1462
1463 /* Setting up the consumer_data pid */
1464 consumer_data->pid = ret;
1465 DBG2("Consumer pid %d", consumer_data->pid);
1466 pthread_mutex_unlock(&consumer_data->pid_mutex);
1467
1468 DBG2("Spawning consumer control thread");
1469 ret = spawn_consumer_thread(consumer_data);
1470 if (ret < 0) {
1471 ERR("Fatal error spawning consumer control thread");
1472 goto error;
1473 }
1474
1475 end:
1476 return 0;
1477
1478 error:
1479 return ret;
1480 }
1481
1482 /*
1483 * modprobe_kernel_modules
1484 */
1485 static int modprobe_kernel_modules(void)
1486 {
1487 int ret = 0, i;
1488 char modprobe[256];
1489
1490 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1491 ret = snprintf(modprobe, sizeof(modprobe),
1492 "/sbin/modprobe %s%s",
1493 kernel_modules_list[i].required ? "" : "-q ",
1494 kernel_modules_list[i].name);
1495 if (ret < 0) {
1496 perror("snprintf modprobe");
1497 goto error;
1498 }
1499 modprobe[sizeof(modprobe) - 1] = '\0';
1500 ret = system(modprobe);
1501 if (ret == -1) {
1502 ERR("Unable to launch modprobe for module %s",
1503 kernel_modules_list[i].name);
1504 } else if (kernel_modules_list[i].required
1505 && WEXITSTATUS(ret) != 0) {
1506 ERR("Unable to load module %s",
1507 kernel_modules_list[i].name);
1508 } else {
1509 DBG("Modprobe successfully %s",
1510 kernel_modules_list[i].name);
1511 }
1512 }
1513
1514 error:
1515 return ret;
1516 }
1517
1518 /*
1519 * mount_debugfs
1520 */
1521 static int mount_debugfs(char *path)
1522 {
1523 int ret;
1524 char *type = "debugfs";
1525
1526 ret = mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1527 if (ret < 0) {
1528 PERROR("Cannot create debugfs path");
1529 goto error;
1530 }
1531
1532 ret = mount(type, path, type, 0, NULL);
1533 if (ret < 0) {
1534 PERROR("Cannot mount debugfs");
1535 goto error;
1536 }
1537
1538 DBG("Mounted debugfs successfully at %s", path);
1539
1540 error:
1541 return ret;
1542 }
1543
1544 /*
1545 * Setup necessary data for kernel tracer action.
1546 */
1547 static void init_kernel_tracer(void)
1548 {
1549 int ret;
1550 char *proc_mounts = "/proc/mounts";
1551 char line[256];
1552 char *debugfs_path = NULL, *lttng_path = NULL;
1553 FILE *fp;
1554
1555 /* Detect debugfs */
1556 fp = fopen(proc_mounts, "r");
1557 if (fp == NULL) {
1558 ERR("Unable to probe %s", proc_mounts);
1559 goto error;
1560 }
1561
1562 while (fgets(line, sizeof(line), fp) != NULL) {
1563 if (strstr(line, "debugfs") != NULL) {
1564 /* Remove first string */
1565 strtok(line, " ");
1566 /* Dup string here so we can reuse line later on */
1567 debugfs_path = strdup(strtok(NULL, " "));
1568 DBG("Got debugfs path : %s", debugfs_path);
1569 break;
1570 }
1571 }
1572
1573 fclose(fp);
1574
1575 /* Mount debugfs if needded */
1576 if (debugfs_path == NULL) {
1577 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1578 if (ret < 0) {
1579 perror("asprintf debugfs path");
1580 goto error;
1581 }
1582 ret = mount_debugfs(debugfs_path);
1583 if (ret < 0) {
1584 perror("Cannot mount debugfs");
1585 goto error;
1586 }
1587 }
1588
1589 /* Modprobe lttng kernel modules */
1590 ret = modprobe_kernel_modules();
1591 if (ret < 0) {
1592 goto error;
1593 }
1594
1595 /* Setup lttng kernel path */
1596 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1597 if (ret < 0) {
1598 perror("asprintf lttng path");
1599 goto error;
1600 }
1601
1602 /* Open debugfs lttng */
1603 kernel_tracer_fd = open(lttng_path, O_RDWR);
1604 if (kernel_tracer_fd < 0) {
1605 DBG("Failed to open %s", lttng_path);
1606 goto error;
1607 }
1608
1609 free(lttng_path);
1610 free(debugfs_path);
1611 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1612 return;
1613
1614 error:
1615 if (lttng_path) {
1616 free(lttng_path);
1617 }
1618 if (debugfs_path) {
1619 free(debugfs_path);
1620 }
1621 WARN("No kernel tracer available");
1622 kernel_tracer_fd = 0;
1623 return;
1624 }
1625
1626 /*
1627 * Init tracing by creating trace directory and sending fds kernel consumer.
1628 */
1629 static int init_kernel_tracing(struct ltt_kernel_session *session)
1630 {
1631 int ret = 0;
1632
1633 if (session->consumer_fds_sent == 0) {
1634 /*
1635 * Assign default kernel consumer socket if no consumer assigned to the
1636 * kernel session. At this point, it's NOT suppose to be 0 but this is
1637 * an extra security check.
1638 */
1639 if (session->consumer_fd == 0) {
1640 session->consumer_fd = kconsumer_data.cmd_sock;
1641 }
1642
1643 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1644 if (ret < 0) {
1645 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1646 goto error;
1647 }
1648
1649 session->consumer_fds_sent = 1;
1650 }
1651
1652 error:
1653 return ret;
1654 }
1655
1656 /*
1657 * Create an UST session and add it to the session ust list.
1658 */
1659 static int create_ust_session(struct ltt_session *session,
1660 struct lttng_domain *domain)
1661 {
1662 int ret;
1663 unsigned int uid;
1664 struct ltt_ust_session *lus = NULL;
1665
1666 switch (domain->type) {
1667 case LTTNG_DOMAIN_UST:
1668 break;
1669 default:
1670 ret = LTTCOMM_UNKNOWN_DOMAIN;
1671 goto error;
1672 }
1673
1674 DBG("Creating UST session");
1675
1676 session_lock_list();
1677 uid = session_list_ptr->count;
1678 session_unlock_list();
1679
1680 lus = trace_ust_create_session(session->path, uid, domain);
1681 if (lus == NULL) {
1682 ret = LTTCOMM_UST_SESS_FAIL;
1683 goto error;
1684 }
1685
1686 ret = mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1687 geteuid(), allowed_group());
1688 if (ret < 0) {
1689 if (ret != -EEXIST) {
1690 ERR("Trace directory creation error");
1691 ret = LTTCOMM_UST_SESS_FAIL;
1692 goto error;
1693 }
1694 }
1695
1696 /* The domain type dictate different actions on session creation */
1697 switch (domain->type) {
1698 case LTTNG_DOMAIN_UST:
1699 /* No ustctl for the global UST domain */
1700 break;
1701 default:
1702 goto error;
1703 }
1704 session->ust_session = lus;
1705
1706 return LTTCOMM_OK;
1707
1708 error:
1709 free(lus);
1710 return ret;
1711 }
1712
1713 /*
1714 * Create a kernel tracer session then create the default channel.
1715 */
1716 static int create_kernel_session(struct ltt_session *session)
1717 {
1718 int ret;
1719
1720 DBG("Creating kernel session");
1721
1722 ret = kernel_create_session(session, kernel_tracer_fd);
1723 if (ret < 0) {
1724 ret = LTTCOMM_KERN_SESS_FAIL;
1725 goto error;
1726 }
1727
1728 /* Set kernel consumer socket fd */
1729 if (kconsumer_data.cmd_sock) {
1730 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1731 }
1732
1733 ret = mkdir_recursive(session->kernel_session->trace_path,
1734 S_IRWXU | S_IRWXG, geteuid(), allowed_group());
1735 if (ret < 0) {
1736 if (ret != -EEXIST) {
1737 ERR("Trace directory creation error");
1738 goto error;
1739 }
1740 }
1741
1742 error:
1743 return ret;
1744 }
1745
1746 /*
1747 * Using the session list, filled a lttng_session array to send back to the
1748 * client for session listing.
1749 *
1750 * The session list lock MUST be acquired before calling this function. Use
1751 * session_lock_list() and session_unlock_list().
1752 */
1753 static void list_lttng_sessions(struct lttng_session *sessions)
1754 {
1755 int i = 0;
1756 struct ltt_session *session;
1757
1758 DBG("Getting all available session");
1759 /*
1760 * Iterate over session list and append data after the control struct in
1761 * the buffer.
1762 */
1763 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1764 strncpy(sessions[i].path, session->path, PATH_MAX);
1765 sessions[i].path[PATH_MAX - 1] = '\0';
1766 strncpy(sessions[i].name, session->name, NAME_MAX);
1767 sessions[i].name[NAME_MAX - 1] = '\0';
1768 i++;
1769 }
1770 }
1771
1772 /*
1773 * Fill lttng_channel array of all channels.
1774 */
1775 static void list_lttng_channels(struct ltt_session *session,
1776 struct lttng_channel *channels)
1777 {
1778 int i = 0;
1779 struct ltt_kernel_channel *kchan;
1780
1781 DBG("Listing channels for session %s", session->name);
1782
1783 /* Kernel channels */
1784 if (session->kernel_session != NULL) {
1785 cds_list_for_each_entry(kchan,
1786 &session->kernel_session->channel_list.head, list) {
1787 /* Copy lttng_channel struct to array */
1788 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
1789 channels[i].enabled = kchan->enabled;
1790 i++;
1791 }
1792 }
1793
1794 /* TODO: Missing UST listing */
1795 }
1796
1797 /*
1798 * Fill lttng_event array of all events in the channel.
1799 */
1800 static void list_lttng_events(struct ltt_kernel_channel *kchan,
1801 struct lttng_event *events)
1802 {
1803 /*
1804 * TODO: This is ONLY kernel. Need UST support.
1805 */
1806 int i = 0;
1807 struct ltt_kernel_event *event;
1808
1809 DBG("Listing events for channel %s", kchan->channel->name);
1810
1811 /* Kernel channels */
1812 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
1813 strncpy(events[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
1814 events[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
1815 events[i].enabled = event->enabled;
1816 switch (event->event->instrumentation) {
1817 case LTTNG_KERNEL_TRACEPOINT:
1818 events[i].type = LTTNG_EVENT_TRACEPOINT;
1819 break;
1820 case LTTNG_KERNEL_KPROBE:
1821 case LTTNG_KERNEL_KRETPROBE:
1822 events[i].type = LTTNG_EVENT_PROBE;
1823 memcpy(&events[i].attr.probe, &event->event->u.kprobe,
1824 sizeof(struct lttng_kernel_kprobe));
1825 break;
1826 case LTTNG_KERNEL_FUNCTION:
1827 events[i].type = LTTNG_EVENT_FUNCTION;
1828 memcpy(&events[i].attr.ftrace, &event->event->u.ftrace,
1829 sizeof(struct lttng_kernel_function));
1830 break;
1831 case LTTNG_KERNEL_NOOP:
1832 events[i].type = LTTNG_EVENT_NOOP;
1833 break;
1834 case LTTNG_KERNEL_SYSCALL:
1835 events[i].type = LTTNG_EVENT_SYSCALL;
1836 break;
1837 case LTTNG_KERNEL_ALL:
1838 assert(0);
1839 break;
1840 }
1841 i++;
1842 }
1843 }
1844
1845 /*
1846 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1847 */
1848 static int cmd_disable_channel(struct ltt_session *session,
1849 int domain, char *channel_name)
1850 {
1851 int ret;
1852
1853 switch (domain) {
1854 case LTTNG_DOMAIN_KERNEL:
1855 ret = channel_kernel_disable(session->kernel_session,
1856 channel_name);
1857 if (ret != LTTCOMM_OK) {
1858 goto error;
1859 }
1860
1861 kernel_wait_quiescent(kernel_tracer_fd);
1862 break;
1863 case LTTNG_DOMAIN_UST_PID:
1864 break;
1865 default:
1866 ret = LTTCOMM_UNKNOWN_DOMAIN;
1867 goto error;
1868 }
1869
1870 ret = LTTCOMM_OK;
1871
1872 error:
1873 return ret;
1874 }
1875
1876 /*
1877 * Copy channel from attributes and set it in the application channel list.
1878 */
1879 /*
1880 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
1881 struct lttng_channel *attr, struct ust_app *app)
1882 {
1883 int ret;
1884 struct ltt_ust_channel *uchan, *new_chan;
1885
1886 uchan = trace_ust_get_channel_by_key(usess->channels, attr->name);
1887 if (uchan == NULL) {
1888 ret = LTTCOMM_FATAL;
1889 goto error;
1890 }
1891
1892 new_chan = trace_ust_create_channel(attr, usess->path);
1893 if (new_chan == NULL) {
1894 PERROR("malloc ltt_ust_channel");
1895 ret = LTTCOMM_FATAL;
1896 goto error;
1897 }
1898
1899 ret = channel_ust_copy(new_chan, uchan);
1900 if (ret < 0) {
1901 ret = LTTCOMM_FATAL;
1902 goto error;
1903 }
1904
1905 error:
1906 return ret;
1907 }
1908 */
1909
1910 /*
1911 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1912 */
1913 static int cmd_enable_channel(struct ltt_session *session,
1914 struct lttng_domain *domain, struct lttng_channel *attr)
1915 {
1916 int ret;
1917 struct ltt_ust_session *usess = session->ust_session;
1918
1919 DBG("Enabling channel %s for session %s", session->name, attr->name);
1920
1921 switch (domain->type) {
1922 case LTTNG_DOMAIN_KERNEL:
1923 {
1924 struct ltt_kernel_channel *kchan;
1925
1926 kchan = trace_kernel_get_channel_by_name(attr->name,
1927 session->kernel_session);
1928 if (kchan == NULL) {
1929 ret = channel_kernel_create(session->kernel_session,
1930 attr, kernel_poll_pipe[1]);
1931 } else {
1932 ret = channel_kernel_enable(session->kernel_session, kchan);
1933 }
1934
1935 if (ret != LTTCOMM_OK) {
1936 goto error;
1937 }
1938
1939 kernel_wait_quiescent(kernel_tracer_fd);
1940 break;
1941 }
1942 case LTTNG_DOMAIN_UST:
1943 {
1944 struct ltt_ust_channel *uchan;
1945
1946 DBG2("Enabling channel for LTTNG_DOMAIN_UST");
1947
1948 /* Get channel in global UST domain HT */
1949 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1950 attr->name);
1951 if (uchan == NULL) {
1952 uchan = trace_ust_create_channel(attr, usess->pathname);
1953 if (uchan == NULL) {
1954 ret = LTTCOMM_UST_CHAN_FAIL;
1955 goto error;
1956 }
1957 rcu_read_lock();
1958 hashtable_add_unique(usess->domain_global.channels, &uchan->node);
1959 rcu_read_unlock();
1960 DBG2("UST channel %s added to global domain HT", attr->name);
1961 } else {
1962 ret = LTTCOMM_UST_CHAN_EXIST;
1963 goto error;
1964 }
1965
1966 ret = ust_app_add_channel(usess, uchan);
1967 if (ret != LTTCOMM_OK) {
1968 goto error;
1969 }
1970
1971 break;
1972 }
1973 case LTTNG_DOMAIN_UST_PID:
1974 {
1975 /*
1976 int sock;
1977 struct ltt_ust_channel *uchan;
1978 struct ltt_ust_session *usess;
1979 struct ust_app *app;
1980
1981 usess = trace_ust_get_session_by_pid(&session->ust_session_list,
1982 domain->attr.pid);
1983 if (usess == NULL) {
1984 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
1985 goto error;
1986 }
1987
1988 app = ust_app_get_by_pid(domain->attr.pid);
1989 if (app == NULL) {
1990 ret = LTTCOMM_APP_NOT_FOUND;
1991 goto error;
1992 }
1993 sock = app->sock;
1994
1995 uchan = trace_ust_get_channel_by_name(attr->name, usess);
1996 if (uchan == NULL) {
1997 ret = channel_ust_create(usess, attr, sock);
1998 } else {
1999 ret = channel_ust_enable(usess, uchan, sock);
2000 }
2001
2002 if (ret != LTTCOMM_OK) {
2003 goto error;
2004 }
2005
2006 ret = copy_ust_channel_to_app(usess, attr, app);
2007 if (ret != LTTCOMM_OK) {
2008 goto error;
2009 }
2010
2011 DBG("UST channel %s created for app sock %d with pid %d",
2012 attr->name, app->sock, domain->attr.pid);
2013 */
2014 ret = LTTCOMM_NOT_IMPLEMENTED;
2015 goto error;
2016 }
2017 default:
2018 ret = LTTCOMM_UNKNOWN_DOMAIN;
2019 goto error;
2020 }
2021
2022 ret = LTTCOMM_OK;
2023
2024 error:
2025 return ret;
2026 }
2027
2028 /*
2029 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2030 */
2031 static int cmd_disable_event(struct ltt_session *session, int domain,
2032 char *channel_name, char *event_name)
2033 {
2034 int ret;
2035
2036 switch (domain) {
2037 case LTTNG_DOMAIN_KERNEL:
2038 {
2039 struct ltt_kernel_channel *kchan;
2040
2041 kchan = trace_kernel_get_channel_by_name(channel_name,
2042 session->kernel_session);
2043 if (kchan == NULL) {
2044 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2045 goto error;
2046 }
2047
2048 ret = event_kernel_disable_tracepoint(session->kernel_session, kchan, event_name);
2049 if (ret != LTTCOMM_OK) {
2050 goto error;
2051 }
2052
2053 kernel_wait_quiescent(kernel_tracer_fd);
2054 break;
2055 }
2056 case LTTNG_DOMAIN_UST:
2057 case LTTNG_DOMAIN_UST_EXEC_NAME:
2058 case LTTNG_DOMAIN_UST_PID:
2059 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2060 default:
2061 /* TODO: Other UST domains */
2062 ret = LTTCOMM_NOT_IMPLEMENTED;
2063 goto error;
2064 }
2065
2066 ret = LTTCOMM_OK;
2067
2068 error:
2069 return ret;
2070 }
2071
2072 /*
2073 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2074 */
2075 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2076 char *channel_name)
2077 {
2078 int ret;
2079 struct ltt_kernel_channel *kchan;
2080
2081 switch (domain) {
2082 case LTTNG_DOMAIN_KERNEL:
2083 kchan = trace_kernel_get_channel_by_name(channel_name,
2084 session->kernel_session);
2085 if (kchan == NULL) {
2086 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2087 goto error;
2088 }
2089
2090 ret = event_kernel_disable_all(session->kernel_session, kchan);
2091 if (ret != LTTCOMM_OK) {
2092 goto error;
2093 }
2094
2095 kernel_wait_quiescent(kernel_tracer_fd);
2096 break;
2097 default:
2098 /* TODO: Userspace tracing */
2099 ret = LTTCOMM_NOT_IMPLEMENTED;
2100 goto error;
2101 }
2102
2103 ret = LTTCOMM_OK;
2104
2105 error:
2106 return ret;
2107 }
2108
2109 /*
2110 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2111 */
2112 static int cmd_add_context(struct ltt_session *session, int domain,
2113 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2114 {
2115 int ret;
2116
2117 switch (domain) {
2118 case LTTNG_DOMAIN_KERNEL:
2119 /* Add kernel context to kernel tracer */
2120 ret = context_kernel_add(session->kernel_session, ctx,
2121 event_name, channel_name);
2122 if (ret != LTTCOMM_OK) {
2123 goto error;
2124 }
2125 break;
2126 case LTTNG_DOMAIN_UST:
2127 {
2128 /*
2129 struct ltt_ust_session *usess;
2130
2131 cds_list_for_each_entry(usess, &session->ust_session_list.head, list) {
2132 ret = context_ust_add(usess, ctx,
2133 event_name, channel_name, domain);
2134 if (ret != LTTCOMM_OK) {
2135 goto error;
2136 }
2137 }
2138 break;
2139 */
2140 }
2141 default:
2142 /* TODO: UST other domains */
2143 ret = LTTCOMM_NOT_IMPLEMENTED;
2144 goto error;
2145 }
2146
2147 ret = LTTCOMM_OK;
2148
2149 error:
2150 return ret;
2151 }
2152
2153 /*
2154 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2155 */
2156 static int cmd_enable_event(struct ltt_session *session, int domain,
2157 char *channel_name, struct lttng_event *event)
2158 {
2159 int ret;
2160 struct lttng_channel *attr;
2161 struct ltt_ust_session *usess = session->ust_session;
2162
2163 switch (domain) {
2164 case LTTNG_DOMAIN_KERNEL:
2165 {
2166 struct ltt_kernel_channel *kchan;
2167
2168 kchan = trace_kernel_get_channel_by_name(channel_name,
2169 session->kernel_session);
2170 if (kchan == NULL) {
2171 attr = channel_new_default_attr(domain);
2172 if (attr == NULL) {
2173 ret = LTTCOMM_FATAL;
2174 goto error;
2175 }
2176 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2177
2178 /* This call will notify the kernel thread */
2179 ret = channel_kernel_create(session->kernel_session,
2180 attr, kernel_poll_pipe[1]);
2181 if (ret != LTTCOMM_OK) {
2182 goto error;
2183 }
2184 }
2185
2186 /* Get the newly created kernel channel pointer */
2187 kchan = trace_kernel_get_channel_by_name(channel_name,
2188 session->kernel_session);
2189 if (kchan == NULL) {
2190 /* This sould not happen... */
2191 ret = LTTCOMM_FATAL;
2192 goto error;
2193 }
2194
2195 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2196 event);
2197 if (ret != LTTCOMM_OK) {
2198 goto error;
2199 }
2200
2201 kernel_wait_quiescent(kernel_tracer_fd);
2202 break;
2203 }
2204 case LTTNG_DOMAIN_UST:
2205 {
2206 struct ltt_ust_channel *uchan;
2207 struct ltt_ust_event *uevent;
2208
2209 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2210 channel_name);
2211 if (uchan == NULL) {
2212 /* TODO: Create default channel */
2213 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2214 goto error;
2215 }
2216
2217 uevent = trace_ust_find_event_by_name(uchan->events, event->name);
2218 if (uevent == NULL) {
2219 uevent = trace_ust_create_event(event);
2220 if (uevent == NULL) {
2221 ret = LTTCOMM_FATAL;
2222 goto error;
2223 }
2224 }
2225
2226 ret = ust_app_add_event(usess, uchan, uevent);
2227 if (ret < 0) {
2228 ret = LTTCOMM_UST_ENABLE_FAIL;
2229 goto error;
2230 }
2231 break;
2232 }
2233 case LTTNG_DOMAIN_UST_EXEC_NAME:
2234 case LTTNG_DOMAIN_UST_PID:
2235 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2236 default:
2237 ret = LTTCOMM_NOT_IMPLEMENTED;
2238 goto error;
2239 }
2240
2241 ret = LTTCOMM_OK;
2242
2243 error:
2244 return ret;
2245 }
2246
2247 /*
2248 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2249 */
2250 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2251 char *channel_name, int event_type)
2252 {
2253 int ret;
2254 struct ltt_kernel_channel *kchan;
2255
2256 switch (domain) {
2257 case LTTNG_DOMAIN_KERNEL:
2258 kchan = trace_kernel_get_channel_by_name(channel_name,
2259 session->kernel_session);
2260 if (kchan == NULL) {
2261 /* This call will notify the kernel thread */
2262 ret = channel_kernel_create(session->kernel_session, NULL,
2263 kernel_poll_pipe[1]);
2264 if (ret != LTTCOMM_OK) {
2265 goto error;
2266 }
2267 }
2268
2269 /* Get the newly created kernel channel pointer */
2270 kchan = trace_kernel_get_channel_by_name(channel_name,
2271 session->kernel_session);
2272 if (kchan == NULL) {
2273 /* This sould not happen... */
2274 ret = LTTCOMM_FATAL;
2275 goto error;
2276 }
2277
2278 switch (event_type) {
2279 case LTTNG_KERNEL_SYSCALL:
2280 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2281 kchan, kernel_tracer_fd);
2282 break;
2283 case LTTNG_KERNEL_TRACEPOINT:
2284 /*
2285 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2286 * events already registered to the channel.
2287 */
2288 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2289 kchan, kernel_tracer_fd);
2290 break;
2291 case LTTNG_KERNEL_ALL:
2292 /* Enable syscalls and tracepoints */
2293 ret = event_kernel_enable_all(session->kernel_session,
2294 kchan, kernel_tracer_fd);
2295 break;
2296 default:
2297 ret = LTTCOMM_KERN_ENABLE_FAIL;
2298 goto error;
2299 }
2300 if (ret != LTTCOMM_OK) {
2301 goto error;
2302 }
2303
2304 kernel_wait_quiescent(kernel_tracer_fd);
2305 break;
2306 default:
2307 /* TODO: Userspace tracing */
2308 ret = LTTCOMM_NOT_IMPLEMENTED;
2309 goto error;
2310 }
2311
2312 ret = LTTCOMM_OK;
2313
2314 error:
2315 return ret;
2316 }
2317
2318 /*
2319 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2320 */
2321 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2322 {
2323 int ret;
2324 ssize_t nb_events = 0;
2325
2326 switch (domain) {
2327 case LTTNG_DOMAIN_KERNEL:
2328 nb_events = kernel_list_events(kernel_tracer_fd, events);
2329 if (nb_events < 0) {
2330 ret = LTTCOMM_KERN_LIST_FAIL;
2331 goto error;
2332 }
2333 break;
2334 default:
2335 /* TODO: Userspace listing */
2336 ret = LTTCOMM_NOT_IMPLEMENTED;
2337 goto error;
2338 }
2339
2340 return nb_events;
2341
2342 error:
2343 /* Return negative value to differentiate return code */
2344 return -ret;
2345 }
2346
2347 /*
2348 * Command LTTNG_START_TRACE processed by the client thread.
2349 */
2350 static int cmd_start_trace(struct ltt_session *session)
2351 {
2352 int ret;
2353 struct ltt_kernel_session *ksession;
2354 struct ltt_ust_session *usess = session->ust_session;
2355
2356 /* Short cut */
2357 ksession = session->kernel_session;
2358
2359 /* Kernel tracing */
2360 if (ksession != NULL) {
2361 struct ltt_kernel_channel *kchan;
2362
2363 /* Open kernel metadata */
2364 if (ksession->metadata == NULL) {
2365 ret = kernel_open_metadata(ksession, ksession->trace_path);
2366 if (ret < 0) {
2367 ret = LTTCOMM_KERN_META_FAIL;
2368 goto error;
2369 }
2370 }
2371
2372 /* Open kernel metadata stream */
2373 if (ksession->metadata_stream_fd == 0) {
2374 ret = kernel_open_metadata_stream(ksession);
2375 if (ret < 0) {
2376 ERR("Kernel create metadata stream failed");
2377 ret = LTTCOMM_KERN_STREAM_FAIL;
2378 goto error;
2379 }
2380 }
2381
2382 /* For each channel */
2383 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2384 if (kchan->stream_count == 0) {
2385 ret = kernel_open_channel_stream(kchan);
2386 if (ret < 0) {
2387 ret = LTTCOMM_KERN_STREAM_FAIL;
2388 goto error;
2389 }
2390 /* Update the stream global counter */
2391 ksession->stream_count_global += ret;
2392 }
2393 }
2394
2395 /* Setup kernel consumer socket and send fds to it */
2396 ret = init_kernel_tracing(ksession);
2397 if (ret < 0) {
2398 ret = LTTCOMM_KERN_START_FAIL;
2399 goto error;
2400 }
2401
2402 /* This start the kernel tracing */
2403 ret = kernel_start_session(ksession);
2404 if (ret < 0) {
2405 ret = LTTCOMM_KERN_START_FAIL;
2406 goto error;
2407 }
2408
2409 /* Quiescent wait after starting trace */
2410 kernel_wait_quiescent(kernel_tracer_fd);
2411 }
2412
2413 ret = ust_app_start_trace(usess);
2414 if (ret < 0) {
2415 ret = LTTCOMM_UST_START_FAIL;
2416 goto error;
2417 }
2418
2419 ret = LTTCOMM_OK;
2420
2421 error:
2422 return ret;
2423 }
2424
2425 /*
2426 * Command LTTNG_STOP_TRACE processed by the client thread.
2427 */
2428 static int cmd_stop_trace(struct ltt_session *session)
2429 {
2430 int ret;
2431 struct ltt_kernel_channel *kchan;
2432 struct ltt_kernel_session *ksession;
2433 //struct ltt_ust_session *usess;
2434 //struct ltt_ust_channel *ustchan;
2435
2436 /* Short cut */
2437 ksession = session->kernel_session;
2438
2439 /* Kernel tracer */
2440 if (ksession != NULL) {
2441 DBG("Stop kernel tracing");
2442
2443 /* Flush all buffers before stopping */
2444 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2445 if (ret < 0) {
2446 ERR("Kernel metadata flush failed");
2447 }
2448
2449 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2450 ret = kernel_flush_buffer(kchan);
2451 if (ret < 0) {
2452 ERR("Kernel flush buffer error");
2453 }
2454 }
2455
2456 ret = kernel_stop_session(ksession);
2457 if (ret < 0) {
2458 ret = LTTCOMM_KERN_STOP_FAIL;
2459 goto error;
2460 }
2461
2462 kernel_wait_quiescent(kernel_tracer_fd);
2463 }
2464
2465 #ifdef DISABLE
2466 /* Stop each UST session */
2467 DBG("Stop UST tracing");
2468 cds_list_for_each_entry(usess, &session->ust_session_list.head, list) {
2469 /* Flush all buffers before stopping */
2470 ret = ustctl_flush_buffer(usess->sock, usess->metadata->obj);
2471 if (ret < 0) {
2472 ERR("UST metadata flush failed");
2473 }
2474
2475 cds_list_for_each_entry(ustchan, &usess->channels.head, list) {
2476 ret = ustctl_flush_buffer(usess->sock, ustchan->obj);
2477 if (ret < 0) {
2478 ERR("UST flush buffer error");
2479 }
2480 }
2481
2482 ret = ustctl_stop_session(usess->sock, usess->handle);
2483 if (ret < 0) {
2484 ret = LTTCOMM_KERN_STOP_FAIL;
2485 goto error;
2486 }
2487
2488 ustctl_wait_quiescent(usess->sock);
2489 }
2490 #endif
2491
2492 ret = LTTCOMM_OK;
2493
2494 error:
2495 return ret;
2496 }
2497
2498 /*
2499 * Command LTTNG_CREATE_SESSION processed by the client thread.
2500 */
2501 static int cmd_create_session(char *name, char *path)
2502 {
2503 int ret;
2504
2505 ret = session_create(name, path);
2506 if (ret != LTTCOMM_OK) {
2507 goto error;
2508 }
2509
2510 ret = LTTCOMM_OK;
2511
2512 error:
2513 return ret;
2514 }
2515
2516 /*
2517 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2518 */
2519 static int cmd_destroy_session(struct ltt_session *session, char *name)
2520 {
2521 int ret;
2522
2523 /* Clean kernel session teardown */
2524 teardown_kernel_session(session);
2525
2526 /*
2527 * Must notify the kernel thread here to update it's poll setin order
2528 * to remove the channel(s)' fd just destroyed.
2529 */
2530 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2531 if (ret < 0) {
2532 perror("write kernel poll pipe");
2533 }
2534
2535 ret = session_destroy(session);
2536
2537 return ret;
2538 }
2539
2540 /*
2541 * Command LTTNG_CALIBRATE processed by the client thread.
2542 */
2543 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2544 {
2545 int ret;
2546
2547 switch (domain) {
2548 case LTTNG_DOMAIN_KERNEL:
2549 {
2550 struct lttng_kernel_calibrate kcalibrate;
2551
2552 kcalibrate.type = calibrate->type;
2553 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2554 if (ret < 0) {
2555 ret = LTTCOMM_KERN_ENABLE_FAIL;
2556 goto error;
2557 }
2558 break;
2559 }
2560 default:
2561 /* TODO: Userspace tracing */
2562 ret = LTTCOMM_NOT_IMPLEMENTED;
2563 goto error;
2564 }
2565
2566 ret = LTTCOMM_OK;
2567
2568 error:
2569 return ret;
2570 }
2571
2572 /*
2573 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2574 */
2575 static int cmd_register_consumer(struct ltt_session *session, int domain,
2576 char *sock_path)
2577 {
2578 int ret, sock;
2579
2580 switch (domain) {
2581 case LTTNG_DOMAIN_KERNEL:
2582 /* Can't register a consumer if there is already one */
2583 if (session->kernel_session->consumer_fd != 0) {
2584 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2585 goto error;
2586 }
2587
2588 sock = lttcomm_connect_unix_sock(sock_path);
2589 if (sock < 0) {
2590 ret = LTTCOMM_CONNECT_FAIL;
2591 goto error;
2592 }
2593
2594 session->kernel_session->consumer_fd = sock;
2595 break;
2596 default:
2597 /* TODO: Userspace tracing */
2598 ret = LTTCOMM_NOT_IMPLEMENTED;
2599 goto error;
2600 }
2601
2602 ret = LTTCOMM_OK;
2603
2604 error:
2605 return ret;
2606 }
2607
2608 /*
2609 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2610 */
2611 static ssize_t cmd_list_domains(struct ltt_session *session,
2612 struct lttng_domain **domains)
2613 {
2614 int ret;
2615 ssize_t nb_dom = 0;
2616
2617 if (session->kernel_session != NULL) {
2618 nb_dom++;
2619 }
2620
2621 /* TODO: User-space tracer domain support */
2622
2623 *domains = malloc(nb_dom * sizeof(struct lttng_domain));
2624 if (*domains == NULL) {
2625 ret = -LTTCOMM_FATAL;
2626 goto error;
2627 }
2628
2629 (*domains)[0].type = LTTNG_DOMAIN_KERNEL;
2630
2631 return nb_dom;
2632
2633 error:
2634 return ret;
2635 }
2636
2637 /*
2638 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2639 */
2640 static ssize_t cmd_list_channels(struct ltt_session *session,
2641 struct lttng_channel **channels)
2642 {
2643 int ret;
2644 ssize_t nb_chan = 0;
2645
2646 if (session->kernel_session != NULL) {
2647 nb_chan += session->kernel_session->channel_count;
2648 }
2649
2650 *channels = malloc(nb_chan * sizeof(struct lttng_channel));
2651 if (*channels == NULL) {
2652 ret = -LTTCOMM_FATAL;
2653 goto error;
2654 }
2655
2656 list_lttng_channels(session, *channels);
2657
2658 /* TODO UST support */
2659
2660 return nb_chan;
2661
2662 error:
2663 return ret;
2664 }
2665
2666 /*
2667 * Command LTTNG_LIST_EVENTS processed by the client thread.
2668 */
2669 static ssize_t cmd_list_events(struct ltt_session *session,
2670 char *channel_name, struct lttng_event **events)
2671 {
2672 int ret;
2673 ssize_t nb_event = 0;
2674 struct ltt_kernel_channel *kchan = NULL;
2675
2676 if (session->kernel_session != NULL) {
2677 kchan = trace_kernel_get_channel_by_name(channel_name,
2678 session->kernel_session);
2679 if (kchan == NULL) {
2680 ret = -LTTCOMM_KERN_CHAN_NOT_FOUND;
2681 goto error;
2682 }
2683 nb_event += kchan->event_count;
2684 }
2685
2686 *events = malloc(nb_event * sizeof(struct lttng_event));
2687 if (*events == NULL) {
2688 ret = -LTTCOMM_FATAL;
2689 goto error;
2690 }
2691
2692 list_lttng_events(kchan, *events);
2693
2694 /* TODO: User-space tracer support */
2695
2696 return nb_event;
2697
2698 error:
2699 return ret;
2700 }
2701
2702 /*
2703 * Process the command requested by the lttng client within the command
2704 * context structure. This function make sure that the return structure (llm)
2705 * is set and ready for transmission before returning.
2706 *
2707 * Return any error encountered or 0 for success.
2708 */
2709 static int process_client_msg(struct command_ctx *cmd_ctx)
2710 {
2711 int ret = LTTCOMM_OK;
2712 int need_tracing_session = 1;
2713
2714 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
2715
2716 /*
2717 * Check for command that don't needs to allocate a returned payload. We do
2718 * this here so we don't have to make the call for no payload at each
2719 * command.
2720 */
2721 switch(cmd_ctx->lsm->cmd_type) {
2722 case LTTNG_LIST_SESSIONS:
2723 case LTTNG_LIST_TRACEPOINTS:
2724 case LTTNG_LIST_DOMAINS:
2725 case LTTNG_LIST_CHANNELS:
2726 case LTTNG_LIST_EVENTS:
2727 break;
2728 default:
2729 /* Setup lttng message with no payload */
2730 ret = setup_lttng_msg(cmd_ctx, 0);
2731 if (ret < 0) {
2732 /* This label does not try to unlock the session */
2733 goto init_setup_error;
2734 }
2735 }
2736
2737 /* Commands that DO NOT need a session. */
2738 switch (cmd_ctx->lsm->cmd_type) {
2739 case LTTNG_CALIBRATE:
2740 case LTTNG_CREATE_SESSION:
2741 case LTTNG_LIST_SESSIONS:
2742 case LTTNG_LIST_TRACEPOINTS:
2743 need_tracing_session = 0;
2744 break;
2745 default:
2746 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
2747 session_lock_list();
2748 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
2749 session_unlock_list();
2750 if (cmd_ctx->session == NULL) {
2751 if (cmd_ctx->lsm->session.name != NULL) {
2752 ret = LTTCOMM_SESS_NOT_FOUND;
2753 } else {
2754 /* If no session name specified */
2755 ret = LTTCOMM_SELECT_SESS;
2756 }
2757 goto error;
2758 } else {
2759 /* Acquire lock for the session */
2760 session_lock(cmd_ctx->session);
2761 }
2762 break;
2763 }
2764
2765 /*
2766 * Check domain type for specific "pre-action".
2767 */
2768 switch (cmd_ctx->lsm->domain.type) {
2769 case LTTNG_DOMAIN_KERNEL:
2770 /* Kernel tracer check */
2771 if (kernel_tracer_fd == 0) {
2772 /* Basically, load kernel tracer modules */
2773 init_kernel_tracer();
2774 if (kernel_tracer_fd == 0) {
2775 ret = LTTCOMM_KERN_NA;
2776 goto error;
2777 }
2778 }
2779
2780 /* Need a session for kernel command */
2781 if (need_tracing_session) {
2782 if (cmd_ctx->session->kernel_session == NULL) {
2783 ret = create_kernel_session(cmd_ctx->session);
2784 if (ret < 0) {
2785 ret = LTTCOMM_KERN_SESS_FAIL;
2786 goto error;
2787 }
2788 }
2789
2790 /* Start the kernel consumer daemon */
2791 pthread_mutex_lock(&kconsumer_data.pid_mutex);
2792 if (kconsumer_data.pid == 0 &&
2793 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
2794 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2795 ret = start_consumerd(&kconsumer_data);
2796 if (ret < 0) {
2797 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2798 goto error;
2799 }
2800 }
2801 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2802 }
2803 break;
2804 case LTTNG_DOMAIN_UST:
2805 {
2806 if (need_tracing_session) {
2807 if (cmd_ctx->session->ust_session == NULL) {
2808 ret = create_ust_session(cmd_ctx->session,
2809 &cmd_ctx->lsm->domain);
2810 if (ret != LTTCOMM_OK) {
2811 goto error;
2812 }
2813 }
2814 /* Start the kernel consumer daemon */
2815 pthread_mutex_lock(&ustconsumer_data.pid_mutex);
2816 if (ustconsumer_data.pid == 0 &&
2817 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
2818 pthread_mutex_unlock(&ustconsumer_data.pid_mutex);
2819 ret = start_consumerd(&ustconsumer_data);
2820 if (ret < 0) {
2821 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2822 goto error;
2823 }
2824
2825 cmd_ctx->session->ust_session->consumer_fd =
2826 ustconsumer_data.cmd_sock;
2827 }
2828 pthread_mutex_unlock(&ustconsumer_data.pid_mutex);
2829 }
2830 break;
2831 }
2832 default:
2833 break;
2834 }
2835
2836 /* Process by command type */
2837 switch (cmd_ctx->lsm->cmd_type) {
2838 case LTTNG_ADD_CONTEXT:
2839 {
2840 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2841 cmd_ctx->lsm->u.context.channel_name,
2842 cmd_ctx->lsm->u.context.event_name,
2843 &cmd_ctx->lsm->u.context.ctx);
2844 break;
2845 }
2846 case LTTNG_DISABLE_CHANNEL:
2847 {
2848 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2849 cmd_ctx->lsm->u.disable.channel_name);
2850 break;
2851 }
2852 case LTTNG_DISABLE_EVENT:
2853 {
2854 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2855 cmd_ctx->lsm->u.disable.channel_name,
2856 cmd_ctx->lsm->u.disable.name);
2857 ret = LTTCOMM_OK;
2858 break;
2859 }
2860 case LTTNG_DISABLE_ALL_EVENT:
2861 {
2862 DBG("Disabling all events");
2863
2864 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2865 cmd_ctx->lsm->u.disable.channel_name);
2866 break;
2867 }
2868 case LTTNG_ENABLE_CHANNEL:
2869 {
2870 ret = cmd_enable_channel(cmd_ctx->session, &cmd_ctx->lsm->domain,
2871 &cmd_ctx->lsm->u.channel.chan);
2872 break;
2873 }
2874 case LTTNG_ENABLE_EVENT:
2875 {
2876 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2877 cmd_ctx->lsm->u.enable.channel_name,
2878 &cmd_ctx->lsm->u.enable.event);
2879 break;
2880 }
2881 case LTTNG_ENABLE_ALL_EVENT:
2882 {
2883 DBG("Enabling all events");
2884
2885 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2886 cmd_ctx->lsm->u.enable.channel_name,
2887 cmd_ctx->lsm->u.enable.event.type);
2888 break;
2889 }
2890 case LTTNG_LIST_TRACEPOINTS:
2891 {
2892 struct lttng_event *events;
2893 ssize_t nb_events;
2894
2895 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
2896 if (nb_events < 0) {
2897 ret = -nb_events;
2898 goto error;
2899 }
2900
2901 /*
2902 * Setup lttng message with payload size set to the event list size in
2903 * bytes and then copy list into the llm payload.
2904 */
2905 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
2906 if (ret < 0) {
2907 free(events);
2908 goto setup_error;
2909 }
2910
2911 /* Copy event list into message payload */
2912 memcpy(cmd_ctx->llm->payload, events,
2913 sizeof(struct lttng_event) * nb_events);
2914
2915 free(events);
2916
2917 ret = LTTCOMM_OK;
2918 break;
2919 }
2920 case LTTNG_START_TRACE:
2921 {
2922 ret = cmd_start_trace(cmd_ctx->session);
2923 break;
2924 }
2925 case LTTNG_STOP_TRACE:
2926 {
2927 ret = cmd_stop_trace(cmd_ctx->session);
2928 break;
2929 }
2930 case LTTNG_CREATE_SESSION:
2931 {
2932 ret = cmd_create_session(cmd_ctx->lsm->session.name,
2933 cmd_ctx->lsm->session.path);
2934 break;
2935 }
2936 case LTTNG_DESTROY_SESSION:
2937 {
2938 ret = cmd_destroy_session(cmd_ctx->session,
2939 cmd_ctx->lsm->session.name);
2940 break;
2941 }
2942 case LTTNG_LIST_DOMAINS:
2943 {
2944 ssize_t nb_dom;
2945 struct lttng_domain *domains;
2946
2947 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
2948 if (nb_dom < 0) {
2949 ret = -nb_dom;
2950 goto error;
2951 }
2952
2953 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
2954 if (ret < 0) {
2955 goto setup_error;
2956 }
2957
2958 /* Copy event list into message payload */
2959 memcpy(cmd_ctx->llm->payload, domains,
2960 nb_dom * sizeof(struct lttng_domain));
2961
2962 free(domains);
2963
2964 ret = LTTCOMM_OK;
2965 break;
2966 }
2967 case LTTNG_LIST_CHANNELS:
2968 {
2969 size_t nb_chan;
2970 struct lttng_channel *channels;
2971
2972 nb_chan = cmd_list_channels(cmd_ctx->session, &channels);
2973 if (nb_chan < 0) {
2974 ret = -nb_chan;
2975 goto error;
2976 }
2977
2978 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
2979 if (ret < 0) {
2980 goto setup_error;
2981 }
2982
2983 /* Copy event list into message payload */
2984 memcpy(cmd_ctx->llm->payload, channels,
2985 nb_chan * sizeof(struct lttng_channel));
2986
2987 free(channels);
2988
2989 ret = LTTCOMM_OK;
2990 break;
2991 }
2992 case LTTNG_LIST_EVENTS:
2993 {
2994 size_t nb_event;
2995 struct lttng_event *events = NULL;
2996
2997 nb_event = cmd_list_events(cmd_ctx->session,
2998 cmd_ctx->lsm->u.list.channel_name, &events);
2999 if (nb_event < 0) {
3000 ret = -nb_event;
3001 goto error;
3002 }
3003
3004 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3005 if (ret < 0) {
3006 goto setup_error;
3007 }
3008
3009 /* Copy event list into message payload */
3010 memcpy(cmd_ctx->llm->payload, events,
3011 nb_event * sizeof(struct lttng_event));
3012
3013 free(events);
3014
3015 ret = LTTCOMM_OK;
3016 break;
3017 }
3018 case LTTNG_LIST_SESSIONS:
3019 {
3020 session_lock_list();
3021
3022 if (session_list_ptr->count == 0) {
3023 ret = LTTCOMM_NO_SESSION;
3024 session_unlock_list();
3025 goto error;
3026 }
3027
3028 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) *
3029 session_list_ptr->count);
3030 if (ret < 0) {
3031 session_unlock_list();
3032 goto setup_error;
3033 }
3034
3035 /* Filled the session array */
3036 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
3037
3038 session_unlock_list();
3039
3040 ret = LTTCOMM_OK;
3041 break;
3042 }
3043 case LTTNG_CALIBRATE:
3044 {
3045 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3046 &cmd_ctx->lsm->u.calibrate);
3047 break;
3048 }
3049 case LTTNG_REGISTER_CONSUMER:
3050 {
3051 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3052 cmd_ctx->lsm->u.reg.path);
3053 break;
3054 }
3055 default:
3056 ret = LTTCOMM_UND;
3057 break;
3058 }
3059
3060 error:
3061 if (cmd_ctx->llm == NULL) {
3062 DBG("Missing llm structure. Allocating one.");
3063 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3064 goto setup_error;
3065 }
3066 }
3067 /* Set return code */
3068 cmd_ctx->llm->ret_code = ret;
3069 setup_error:
3070 if (cmd_ctx->session) {
3071 session_unlock(cmd_ctx->session);
3072 }
3073 init_setup_error:
3074 return ret;
3075 }
3076
3077 /*
3078 * This thread manage all clients request using the unix client socket for
3079 * communication.
3080 */
3081 static void *thread_manage_clients(void *data)
3082 {
3083 int sock = 0, ret, i, pollfd;
3084 uint32_t revents, nb_fd;
3085 struct command_ctx *cmd_ctx = NULL;
3086 struct lttng_poll_event events;
3087
3088 DBG("[thread] Manage client started");
3089
3090 rcu_register_thread();
3091
3092 ret = lttcomm_listen_unix_sock(client_sock);
3093 if (ret < 0) {
3094 goto error;
3095 }
3096
3097 /*
3098 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3099 * more will be added to this poll set.
3100 */
3101 ret = create_thread_poll_set(&events, 2);
3102 if (ret < 0) {
3103 goto error;
3104 }
3105
3106 /* Add the application registration socket */
3107 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3108 if (ret < 0) {
3109 goto error;
3110 }
3111
3112 /*
3113 * Notify parent pid that we are ready to accept command for client side.
3114 */
3115 if (opt_sig_parent) {
3116 kill(ppid, SIGCHLD);
3117 }
3118
3119 while (1) {
3120 DBG("Accepting client command ...");
3121
3122 nb_fd = LTTNG_POLL_GETNB(&events);
3123
3124 /* Inifinite blocking call, waiting for transmission */
3125 ret = lttng_poll_wait(&events, -1);
3126 if (ret < 0) {
3127 goto error;
3128 }
3129
3130 for (i = 0; i < nb_fd; i++) {
3131 /* Fetch once the poll data */
3132 revents = LTTNG_POLL_GETEV(&events, i);
3133 pollfd = LTTNG_POLL_GETFD(&events, i);
3134
3135 /* Thread quit pipe has been closed. Killing thread. */
3136 ret = check_thread_quit_pipe(pollfd, revents);
3137 if (ret) {
3138 goto error;
3139 }
3140
3141 /* Event on the registration socket */
3142 if (pollfd == client_sock) {
3143 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3144 ERR("Client socket poll error");
3145 goto error;
3146 }
3147 }
3148 }
3149
3150 DBG("Wait for client response");
3151
3152 sock = lttcomm_accept_unix_sock(client_sock);
3153 if (sock < 0) {
3154 goto error;
3155 }
3156
3157 /* Allocate context command to process the client request */
3158 cmd_ctx = malloc(sizeof(struct command_ctx));
3159 if (cmd_ctx == NULL) {
3160 perror("malloc cmd_ctx");
3161 goto error;
3162 }
3163
3164 /* Allocate data buffer for reception */
3165 cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
3166 if (cmd_ctx->lsm == NULL) {
3167 perror("malloc cmd_ctx->lsm");
3168 goto error;
3169 }
3170
3171 cmd_ctx->llm = NULL;
3172 cmd_ctx->session = NULL;
3173
3174 /*
3175 * Data is received from the lttng client. The struct
3176 * lttcomm_session_msg (lsm) contains the command and data request of
3177 * the client.
3178 */
3179 DBG("Receiving data from client ...");
3180 ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm,
3181 sizeof(struct lttcomm_session_msg));
3182 if (ret <= 0) {
3183 DBG("Nothing recv() from client... continuing");
3184 close(sock);
3185 free(cmd_ctx);
3186 continue;
3187 }
3188
3189 // TODO: Validate cmd_ctx including sanity check for
3190 // security purpose.
3191
3192 rcu_thread_online();
3193 /*
3194 * This function dispatch the work to the kernel or userspace tracer
3195 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3196 * informations for the client. The command context struct contains
3197 * everything this function may needs.
3198 */
3199 ret = process_client_msg(cmd_ctx);
3200 rcu_thread_offline();
3201 if (ret < 0) {
3202 /*
3203 * TODO: Inform client somehow of the fatal error. At
3204 * this point, ret < 0 means that a malloc failed
3205 * (ENOMEM). Error detected but still accept command.
3206 */
3207 clean_command_ctx(&cmd_ctx);
3208 continue;
3209 }
3210
3211 DBG("Sending response (size: %d, retcode: %s)",
3212 cmd_ctx->lttng_msg_size,
3213 lttng_strerror(-cmd_ctx->llm->ret_code));
3214 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3215 if (ret < 0) {
3216 ERR("Failed to send data back to client");
3217 }
3218
3219 clean_command_ctx(&cmd_ctx);
3220
3221 /* End of transmission */
3222 close(sock);
3223 }
3224
3225 error:
3226 DBG("Client thread dying");
3227 unlink(client_unix_sock_path);
3228 close(client_sock);
3229 close(sock);
3230
3231 lttng_poll_clean(&events);
3232 clean_command_ctx(&cmd_ctx);
3233
3234 rcu_unregister_thread();
3235 return NULL;
3236 }
3237
3238
3239 /*
3240 * usage function on stderr
3241 */
3242 static void usage(void)
3243 {
3244 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3245 fprintf(stderr, " -h, --help Display this usage.\n");
3246 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3247 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3248 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3249 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3250 fprintf(stderr, " --ustconsumerd-err-sock PATH Specify path for the UST consumer error socket\n");
3251 fprintf(stderr, " --ustconsumerd-cmd-sock PATH Specify path for the UST consumer command socket\n");
3252 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3253 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3254 fprintf(stderr, " -V, --version Show version number.\n");
3255 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3256 fprintf(stderr, " -q, --quiet No output at all.\n");
3257 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3258 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3259 }
3260
3261 /*
3262 * daemon argument parsing
3263 */
3264 static int parse_args(int argc, char **argv)
3265 {
3266 int c;
3267
3268 static struct option long_options[] = {
3269 { "client-sock", 1, 0, 'c' },
3270 { "apps-sock", 1, 0, 'a' },
3271 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3272 { "kconsumerd-err-sock", 1, 0, 'E' },
3273 { "ustconsumerd-cmd-sock", 1, 0, 'D' },
3274 { "ustconsumerd-err-sock", 1, 0, 'F' },
3275 { "daemonize", 0, 0, 'd' },
3276 { "sig-parent", 0, 0, 'S' },
3277 { "help", 0, 0, 'h' },
3278 { "group", 1, 0, 'g' },
3279 { "version", 0, 0, 'V' },
3280 { "quiet", 0, 0, 'q' },
3281 { "verbose", 0, 0, 'v' },
3282 { "verbose-consumer", 0, 0, 'Z' },
3283 { NULL, 0, 0, 0 }
3284 };
3285
3286 while (1) {
3287 int option_index = 0;
3288 c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:C:E:D:F:Z",
3289 long_options, &option_index);
3290 if (c == -1) {
3291 break;
3292 }
3293
3294 switch (c) {
3295 case 0:
3296 fprintf(stderr, "option %s", long_options[option_index].name);
3297 if (optarg) {
3298 fprintf(stderr, " with arg %s\n", optarg);
3299 }
3300 break;
3301 case 'c':
3302 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3303 break;
3304 case 'a':
3305 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3306 break;
3307 case 'd':
3308 opt_daemon = 1;
3309 break;
3310 case 'g':
3311 opt_tracing_group = strdup(optarg);
3312 break;
3313 case 'h':
3314 usage();
3315 exit(EXIT_FAILURE);
3316 case 'V':
3317 fprintf(stdout, "%s\n", VERSION);
3318 exit(EXIT_SUCCESS);
3319 case 'S':
3320 opt_sig_parent = 1;
3321 break;
3322 case 'E':
3323 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3324 break;
3325 case 'C':
3326 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3327 break;
3328 case 'F':
3329 snprintf(ustconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3330 break;
3331 case 'D':
3332 snprintf(ustconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3333 break;
3334 case 'q':
3335 opt_quiet = 1;
3336 break;
3337 case 'v':
3338 /* Verbose level can increase using multiple -v */
3339 opt_verbose += 1;
3340 break;
3341 case 'Z':
3342 opt_verbose_consumer += 1;
3343 break;
3344 default:
3345 /* Unknown option or other error.
3346 * Error is printed by getopt, just return */
3347 return -1;
3348 }
3349 }
3350
3351 return 0;
3352 }
3353
3354 /*
3355 * Creates the two needed socket by the daemon.
3356 * apps_sock - The communication socket for all UST apps.
3357 * client_sock - The communication of the cli tool (lttng).
3358 */
3359 static int init_daemon_socket(void)
3360 {
3361 int ret = 0;
3362 mode_t old_umask;
3363
3364 old_umask = umask(0);
3365
3366 /* Create client tool unix socket */
3367 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3368 if (client_sock < 0) {
3369 ERR("Create unix sock failed: %s", client_unix_sock_path);
3370 ret = -1;
3371 goto end;
3372 }
3373
3374 /* File permission MUST be 660 */
3375 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3376 if (ret < 0) {
3377 ERR("Set file permissions failed: %s", client_unix_sock_path);
3378 perror("chmod");
3379 goto end;
3380 }
3381
3382 /* Create the application unix socket */
3383 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3384 if (apps_sock < 0) {
3385 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3386 ret = -1;
3387 goto end;
3388 }
3389
3390 /* File permission MUST be 666 */
3391 ret = chmod(apps_unix_sock_path,
3392 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3393 if (ret < 0) {
3394 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3395 perror("chmod");
3396 goto end;
3397 }
3398
3399 end:
3400 umask(old_umask);
3401 return ret;
3402 }
3403
3404 /*
3405 * Check if the global socket is available, and if a daemon is answering at the
3406 * other side. If yes, error is returned.
3407 */
3408 static int check_existing_daemon(void)
3409 {
3410 if (access(client_unix_sock_path, F_OK) < 0 &&
3411 access(apps_unix_sock_path, F_OK) < 0) {
3412 return 0;
3413 }
3414
3415 /* Is there anybody out there ? */
3416 if (lttng_session_daemon_alive()) {
3417 return -EEXIST;
3418 } else {
3419 return 0;
3420 }
3421 }
3422
3423 /*
3424 * Set the tracing group gid onto the client socket.
3425 *
3426 * Race window between mkdir and chown is OK because we are going from more
3427 * permissive (root.root) to les permissive (root.tracing).
3428 */
3429 static int set_permissions(void)
3430 {
3431 int ret;
3432 gid_t gid;
3433
3434 gid = allowed_group();
3435 if (gid < 0) {
3436 if (is_root) {
3437 WARN("No tracing group detected");
3438 ret = 0;
3439 } else {
3440 ERR("Missing tracing group. Aborting execution.");
3441 ret = -1;
3442 }
3443 goto end;
3444 }
3445
3446 /* Set lttng run dir */
3447 ret = chown(LTTNG_RUNDIR, 0, gid);
3448 if (ret < 0) {
3449 ERR("Unable to set group on " LTTNG_RUNDIR);
3450 perror("chown");
3451 }
3452
3453 /* lttng client socket path */
3454 ret = chown(client_unix_sock_path, 0, gid);
3455 if (ret < 0) {
3456 ERR("Unable to set group on %s", client_unix_sock_path);
3457 perror("chown");
3458 }
3459
3460 /* kconsumer error socket path */
3461 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
3462 if (ret < 0) {
3463 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
3464 perror("chown");
3465 }
3466
3467 /* ustconsumer error socket path */
3468 ret = chown(ustconsumer_data.err_unix_sock_path, 0, gid);
3469 if (ret < 0) {
3470 ERR("Unable to set group on %s", ustconsumer_data.err_unix_sock_path);
3471 perror("chown");
3472 }
3473
3474 DBG("All permissions are set");
3475
3476 end:
3477 return ret;
3478 }
3479
3480 /*
3481 * Create the pipe used to wake up the kernel thread.
3482 */
3483 static int create_kernel_poll_pipe(void)
3484 {
3485 return pipe2(kernel_poll_pipe, O_CLOEXEC);
3486 }
3487
3488 /*
3489 * Create the application command pipe to wake thread_manage_apps.
3490 */
3491 static int create_apps_cmd_pipe(void)
3492 {
3493 return pipe2(apps_cmd_pipe, O_CLOEXEC);
3494 }
3495
3496 /*
3497 * Create the lttng run directory needed for all global sockets and pipe.
3498 */
3499 static int create_lttng_rundir(void)
3500 {
3501 int ret;
3502
3503 ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG );
3504 if (ret < 0) {
3505 if (errno != EEXIST) {
3506 ERR("Unable to create " LTTNG_RUNDIR);
3507 goto error;
3508 } else {
3509 ret = 0;
3510 }
3511 }
3512
3513 error:
3514 return ret;
3515 }
3516
3517 /*
3518 * Setup sockets and directory needed by the kconsumerd communication with the
3519 * session daemon.
3520 */
3521 static int set_consumer_sockets(struct consumer_data *consumer_data)
3522 {
3523 int ret;
3524 const char *path = consumer_data->type == LTTNG_CONSUMER_KERNEL ?
3525 KCONSUMERD_PATH : USTCONSUMERD_PATH;
3526
3527 if (strlen(consumer_data->err_unix_sock_path) == 0) {
3528 snprintf(consumer_data->err_unix_sock_path, PATH_MAX,
3529 consumer_data->type == LTTNG_CONSUMER_KERNEL ?
3530 KCONSUMERD_ERR_SOCK_PATH :
3531 USTCONSUMERD_ERR_SOCK_PATH);
3532 }
3533
3534 if (strlen(consumer_data->cmd_unix_sock_path) == 0) {
3535 snprintf(consumer_data->cmd_unix_sock_path, PATH_MAX,
3536 consumer_data->type == LTTNG_CONSUMER_KERNEL ?
3537 KCONSUMERD_CMD_SOCK_PATH :
3538 USTCONSUMERD_CMD_SOCK_PATH);
3539 }
3540
3541 ret = mkdir(path, S_IRWXU | S_IRWXG);
3542 if (ret < 0) {
3543 if (errno != EEXIST) {
3544 ERR("Failed to create %s", path);
3545 goto error;
3546 }
3547 ret = 0;
3548 }
3549
3550 /* Create the kconsumerd error unix socket */
3551 consumer_data->err_sock =
3552 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
3553 if (consumer_data->err_sock < 0) {
3554 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
3555 ret = -1;
3556 goto error;
3557 }
3558
3559 /* File permission MUST be 660 */
3560 ret = chmod(consumer_data->err_unix_sock_path,
3561 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3562 if (ret < 0) {
3563 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
3564 perror("chmod");
3565 goto error;
3566 }
3567
3568 error:
3569 return ret;
3570 }
3571
3572 /*
3573 * Signal handler for the daemon
3574 *
3575 * Simply stop all worker threads, leaving main() return gracefully after
3576 * joining all threads and calling cleanup().
3577 */
3578 static void sighandler(int sig)
3579 {
3580 switch (sig) {
3581 case SIGPIPE:
3582 DBG("SIGPIPE catched");
3583 return;
3584 case SIGINT:
3585 DBG("SIGINT catched");
3586 stop_threads();
3587 break;
3588 case SIGTERM:
3589 DBG("SIGTERM catched");
3590 stop_threads();
3591 break;
3592 default:
3593 break;
3594 }
3595 }
3596
3597 /*
3598 * Setup signal handler for :
3599 * SIGINT, SIGTERM, SIGPIPE
3600 */
3601 static int set_signal_handler(void)
3602 {
3603 int ret = 0;
3604 struct sigaction sa;
3605 sigset_t sigset;
3606
3607 if ((ret = sigemptyset(&sigset)) < 0) {
3608 perror("sigemptyset");
3609 return ret;
3610 }
3611
3612 sa.sa_handler = sighandler;
3613 sa.sa_mask = sigset;
3614 sa.sa_flags = 0;
3615 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
3616 perror("sigaction");
3617 return ret;
3618 }
3619
3620 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
3621 perror("sigaction");
3622 return ret;
3623 }
3624
3625 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
3626 perror("sigaction");
3627 return ret;
3628 }
3629
3630 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3631
3632 return ret;
3633 }
3634
3635 /*
3636 * Set open files limit to unlimited. This daemon can open a large number of
3637 * file descriptors in order to consumer multiple kernel traces.
3638 */
3639 static void set_ulimit(void)
3640 {
3641 int ret;
3642 struct rlimit lim;
3643
3644 /* The kernel does not allowed an infinite limit for open files */
3645 lim.rlim_cur = 65535;
3646 lim.rlim_max = 65535;
3647
3648 ret = setrlimit(RLIMIT_NOFILE, &lim);
3649 if (ret < 0) {
3650 perror("failed to set open files limit");
3651 }
3652 }
3653
3654 /*
3655 * main
3656 */
3657 int main(int argc, char **argv)
3658 {
3659 int ret = 0;
3660 void *status;
3661 const char *home_path;
3662
3663 rcu_register_thread();
3664
3665 /* Create thread quit pipe */
3666 if ((ret = init_thread_quit_pipe()) < 0) {
3667 goto error;
3668 }
3669
3670 /* Parse arguments */
3671 progname = argv[0];
3672 if ((ret = parse_args(argc, argv) < 0)) {
3673 goto error;
3674 }
3675
3676 /* Daemonize */
3677 if (opt_daemon) {
3678 ret = daemon(0, 0);
3679 if (ret < 0) {
3680 perror("daemon");
3681 goto error;
3682 }
3683 }
3684
3685 /* Check if daemon is UID = 0 */
3686 is_root = !getuid();
3687
3688 if (is_root) {
3689 ret = create_lttng_rundir();
3690 if (ret < 0) {
3691 goto error;
3692 }
3693
3694 if (strlen(apps_unix_sock_path) == 0) {
3695 snprintf(apps_unix_sock_path, PATH_MAX,
3696 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
3697 }
3698
3699 if (strlen(client_unix_sock_path) == 0) {
3700 snprintf(client_unix_sock_path, PATH_MAX,
3701 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
3702 }
3703
3704 /* Set global SHM for ust */
3705 if (strlen(wait_shm_path) == 0) {
3706 snprintf(wait_shm_path, PATH_MAX,
3707 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
3708 }
3709 } else {
3710 home_path = get_home_dir();
3711 if (home_path == NULL) {
3712 /* TODO: Add --socket PATH option */
3713 ERR("Can't get HOME directory for sockets creation.");
3714 ret = -EPERM;
3715 goto error;
3716 }
3717
3718 if (strlen(apps_unix_sock_path) == 0) {
3719 snprintf(apps_unix_sock_path, PATH_MAX,
3720 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
3721 }
3722
3723 /* Set the cli tool unix socket path */
3724 if (strlen(client_unix_sock_path) == 0) {
3725 snprintf(client_unix_sock_path, PATH_MAX,
3726 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
3727 }
3728
3729 /* Set global SHM for ust */
3730 if (strlen(wait_shm_path) == 0) {
3731 snprintf(wait_shm_path, PATH_MAX,
3732 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
3733 }
3734 }
3735
3736 DBG("Client socket path %s", client_unix_sock_path);
3737 DBG("Application socket path %s", apps_unix_sock_path);
3738
3739 /*
3740 * See if daemon already exist.
3741 */
3742 if ((ret = check_existing_daemon()) < 0) {
3743 ERR("Already running daemon.\n");
3744 /*
3745 * We do not goto exit because we must not cleanup()
3746 * because a daemon is already running.
3747 */
3748 goto error;
3749 }
3750
3751 /* After this point, we can safely call cleanup() with "goto exit" */
3752
3753 /*
3754 * These actions must be executed as root. We do that *after* setting up
3755 * the sockets path because we MUST make the check for another daemon using
3756 * those paths *before* trying to set the kernel consumer sockets and init
3757 * kernel tracer.
3758 */
3759 if (is_root) {
3760 ret = set_consumer_sockets(&kconsumer_data);
3761 if (ret < 0) {
3762 goto exit;
3763 }
3764
3765 ret = set_consumer_sockets(&ustconsumer_data);
3766 if (ret < 0) {
3767 goto exit;
3768 }
3769 /* Setup kernel tracer */
3770 init_kernel_tracer();
3771
3772 /* Set ulimit for open files */
3773 set_ulimit();
3774 }
3775
3776 if ((ret = set_signal_handler()) < 0) {
3777 goto exit;
3778 }
3779
3780 /* Setup the needed unix socket */
3781 if ((ret = init_daemon_socket()) < 0) {
3782 goto exit;
3783 }
3784
3785 /* Set credentials to socket */
3786 if (is_root && ((ret = set_permissions()) < 0)) {
3787 goto exit;
3788 }
3789
3790 /* Get parent pid if -S, --sig-parent is specified. */
3791 if (opt_sig_parent) {
3792 ppid = getppid();
3793 }
3794
3795 /* Setup the kernel pipe for waking up the kernel thread */
3796 if ((ret = create_kernel_poll_pipe()) < 0) {
3797 goto exit;
3798 }
3799
3800 /* Setup the thread apps communication pipe. */
3801 if ((ret = create_apps_cmd_pipe()) < 0) {
3802 goto exit;
3803 }
3804
3805 /* Init UST command queue. */
3806 cds_wfq_init(&ust_cmd_queue.queue);
3807
3808 /* Init UST app hash table */
3809 ust_app_ht_alloc();
3810
3811 /*
3812 * Get session list pointer. This pointer MUST NOT be free(). This list is
3813 * statically declared in session.c
3814 */
3815 session_list_ptr = session_get_list();
3816
3817 /* Set up max poll set size */
3818 lttng_poll_set_max_size();
3819
3820 /* Create thread to manage the client socket */
3821 ret = pthread_create(&client_thread, NULL,
3822 thread_manage_clients, (void *) NULL);
3823 if (ret != 0) {
3824 perror("pthread_create clients");
3825 goto exit_client;
3826 }
3827
3828 /* Create thread to dispatch registration */
3829 ret = pthread_create(&dispatch_thread, NULL,
3830 thread_dispatch_ust_registration, (void *) NULL);
3831 if (ret != 0) {
3832 perror("pthread_create dispatch");
3833 goto exit_dispatch;
3834 }
3835
3836 /* Create thread to manage application registration. */
3837 ret = pthread_create(&reg_apps_thread, NULL,
3838 thread_registration_apps, (void *) NULL);
3839 if (ret != 0) {
3840 perror("pthread_create registration");
3841 goto exit_reg_apps;
3842 }
3843
3844 /* Create thread to manage application socket */
3845 ret = pthread_create(&apps_thread, NULL,
3846 thread_manage_apps, (void *) NULL);
3847 if (ret != 0) {
3848 perror("pthread_create apps");
3849 goto exit_apps;
3850 }
3851
3852 /* Create kernel thread to manage kernel event */
3853 ret = pthread_create(&kernel_thread, NULL,
3854 thread_manage_kernel, (void *) NULL);
3855 if (ret != 0) {
3856 perror("pthread_create kernel");
3857 goto exit_kernel;
3858 }
3859
3860 ret = pthread_join(kernel_thread, &status);
3861 if (ret != 0) {
3862 perror("pthread_join");
3863 goto error; /* join error, exit without cleanup */
3864 }
3865
3866 exit_kernel:
3867 ret = pthread_join(apps_thread, &status);
3868 if (ret != 0) {
3869 perror("pthread_join");
3870 goto error; /* join error, exit without cleanup */
3871 }
3872
3873 exit_apps:
3874 ret = pthread_join(reg_apps_thread, &status);
3875 if (ret != 0) {
3876 perror("pthread_join");
3877 goto error; /* join error, exit without cleanup */
3878 }
3879
3880 exit_reg_apps:
3881 ret = pthread_join(dispatch_thread, &status);
3882 if (ret != 0) {