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UST support: send commands to app before register done
[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 if (is_root) {
342 DBG("Removing %s directory", LTTNG_RUNDIR);
343 ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
344 if (ret < 0) {
345 ERR("asprintf failed. Something is really wrong!");
346 }
347
348 /* Remove lttng run directory */
349 ret = system(cmd);
350 if (ret < 0) {
351 ERR("Unable to clean " LTTNG_RUNDIR);
352 }
353 }
354
355 DBG("Cleaning up all session");
356
357 /* Destroy session list mutex */
358 if (session_list_ptr != NULL) {
359 pthread_mutex_destroy(&session_list_ptr->lock);
360
361 /* Cleanup ALL session */
362 cds_list_for_each_entry_safe(sess, stmp,
363 &session_list_ptr->head, list) {
364 teardown_kernel_session(sess);
365 teardown_ust_session(sess);
366 free(sess);
367 }
368 }
369
370 DBG("Closing all UST sockets");
371 ust_app_clean_list();
372
373 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
374
375 DBG("Closing kernel fd");
376 close(kernel_tracer_fd);
377
378 if (is_root) {
379 DBG("Unloading kernel modules");
380 modprobe_remove_kernel_modules();
381 }
382
383 close(thread_quit_pipe[0]);
384 close(thread_quit_pipe[1]);
385
386 /* <fun> */
387 MSG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
388 "Matthew, BEET driven development works!%c[%dm",
389 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
390 /* </fun> */
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 * For each tracing session, update newly registered apps.
716 */
717 static void update_ust_app(int app_sock)
718 {
719 struct ltt_session *sess, *stmp;
720
721 /* For all tracing session(s) */
722 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
723 if (sess->ust_session) {
724 ust_app_global_update(sess->ust_session, app_sock);
725 }
726 }
727 }
728
729 /*
730 * This thread manage event coming from the kernel.
731 *
732 * Features supported in this thread:
733 * -) CPU Hotplug
734 */
735 static void *thread_manage_kernel(void *data)
736 {
737 int ret, i, pollfd, update_poll_flag = 1;
738 uint32_t revents, nb_fd;
739 char tmp;
740 struct lttng_poll_event events;
741
742 DBG("Thread manage kernel started");
743
744 ret = create_thread_poll_set(&events, 2);
745 if (ret < 0) {
746 goto error;
747 }
748
749 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
750 if (ret < 0) {
751 goto error;
752 }
753
754 while (1) {
755 if (update_poll_flag == 1) {
756 /*
757 * Reset number of fd in the poll set. Always 2 since there is the thread
758 * quit pipe and the kernel pipe.
759 */
760 events.nb_fd = 2;
761
762 ret = update_kernel_poll(&events);
763 if (ret < 0) {
764 goto error;
765 }
766 update_poll_flag = 0;
767 }
768
769 nb_fd = LTTNG_POLL_GETNB(&events);
770
771 DBG("Thread kernel polling on %d fds", nb_fd);
772
773 /* Zeroed the poll events */
774 lttng_poll_reset(&events);
775
776 /* Poll infinite value of time */
777 ret = lttng_poll_wait(&events, -1);
778 if (ret < 0) {
779 goto error;
780 } else if (ret == 0) {
781 /* Should not happen since timeout is infinite */
782 ERR("Return value of poll is 0 with an infinite timeout.\n"
783 "This should not have happened! Continuing...");
784 continue;
785 }
786
787 for (i = 0; i < nb_fd; i++) {
788 /* Fetch once the poll data */
789 revents = LTTNG_POLL_GETEV(&events, i);
790 pollfd = LTTNG_POLL_GETFD(&events, i);
791
792 /* Thread quit pipe has been closed. Killing thread. */
793 ret = check_thread_quit_pipe(pollfd, revents);
794 if (ret) {
795 goto error;
796 }
797
798 /* Check for data on kernel pipe */
799 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
800 ret = read(kernel_poll_pipe[0], &tmp, 1);
801 update_poll_flag = 1;
802 continue;
803 } else {
804 /*
805 * New CPU detected by the kernel. Adding kernel stream to
806 * kernel session and updating the kernel consumer
807 */
808 if (revents & LPOLLIN) {
809 ret = update_kernel_stream(&kconsumer_data, pollfd);
810 if (ret < 0) {
811 continue;
812 }
813 break;
814 /*
815 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
816 * and unregister kernel stream at this point.
817 */
818 }
819 }
820 }
821 }
822
823 error:
824 DBG("Kernel thread dying");
825 close(kernel_poll_pipe[0]);
826 close(kernel_poll_pipe[1]);
827
828 lttng_poll_clean(&events);
829
830 return NULL;
831 }
832
833 /*
834 * This thread manage the consumer error sent back to the session daemon.
835 */
836 static void *thread_manage_consumer(void *data)
837 {
838 int sock = 0, i, ret, pollfd;
839 uint32_t revents, nb_fd;
840 enum lttcomm_return_code code;
841 struct lttng_poll_event events;
842 struct consumer_data *consumer_data = data;
843
844 DBG("[thread] Manage consumer started");
845
846 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
847 if (ret < 0) {
848 goto error;
849 }
850
851 /*
852 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
853 * Nothing more will be added to this poll set.
854 */
855 ret = create_thread_poll_set(&events, 2);
856 if (ret < 0) {
857 goto error;
858 }
859
860 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
861 if (ret < 0) {
862 goto error;
863 }
864
865 nb_fd = LTTNG_POLL_GETNB(&events);
866
867 /* Inifinite blocking call, waiting for transmission */
868 ret = lttng_poll_wait(&events, -1);
869 if (ret < 0) {
870 goto error;
871 }
872
873 for (i = 0; i < nb_fd; i++) {
874 /* Fetch once the poll data */
875 revents = LTTNG_POLL_GETEV(&events, i);
876 pollfd = LTTNG_POLL_GETFD(&events, i);
877
878 /* Thread quit pipe has been closed. Killing thread. */
879 ret = check_thread_quit_pipe(pollfd, revents);
880 if (ret) {
881 goto error;
882 }
883
884 /* Event on the registration socket */
885 if (pollfd == consumer_data->err_sock) {
886 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
887 ERR("consumer err socket poll error");
888 goto error;
889 }
890 }
891 }
892
893 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
894 if (sock < 0) {
895 goto error;
896 }
897
898 DBG2("Receiving code from consumer err_sock");
899
900 /* Getting status code from kconsumerd */
901 ret = lttcomm_recv_unix_sock(sock, &code,
902 sizeof(enum lttcomm_return_code));
903 if (ret <= 0) {
904 goto error;
905 }
906
907 if (code == CONSUMERD_COMMAND_SOCK_READY) {
908 consumer_data->cmd_sock =
909 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
910 if (consumer_data->cmd_sock < 0) {
911 sem_post(&consumer_data->sem);
912 PERROR("consumer connect");
913 goto error;
914 }
915 /* Signal condition to tell that the kconsumerd is ready */
916 sem_post(&consumer_data->sem);
917 DBG("consumer command socket ready");
918 } else {
919 ERR("consumer error when waiting for SOCK_READY : %s",
920 lttcomm_get_readable_code(-code));
921 goto error;
922 }
923
924 /* Remove the kconsumerd error sock since we've established a connexion */
925 ret = lttng_poll_del(&events, consumer_data->err_sock);
926 if (ret < 0) {
927 goto error;
928 }
929
930 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
931 if (ret < 0) {
932 goto error;
933 }
934
935 /* Update number of fd */
936 nb_fd = LTTNG_POLL_GETNB(&events);
937
938 /* Inifinite blocking call, waiting for transmission */
939 ret = lttng_poll_wait(&events, -1);
940 if (ret < 0) {
941 goto error;
942 }
943
944 for (i = 0; i < nb_fd; i++) {
945 /* Fetch once the poll data */
946 revents = LTTNG_POLL_GETEV(&events, i);
947 pollfd = LTTNG_POLL_GETFD(&events, i);
948
949 /* Thread quit pipe has been closed. Killing thread. */
950 ret = check_thread_quit_pipe(pollfd, revents);
951 if (ret) {
952 goto error;
953 }
954
955 /* Event on the kconsumerd socket */
956 if (pollfd == sock) {
957 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
958 ERR("consumer err socket second poll error");
959 goto error;
960 }
961 }
962 }
963
964 /* Wait for any kconsumerd error */
965 ret = lttcomm_recv_unix_sock(sock, &code,
966 sizeof(enum lttcomm_return_code));
967 if (ret <= 0) {
968 ERR("consumer closed the command socket");
969 goto error;
970 }
971
972 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
973
974 error:
975 DBG("consumer thread dying");
976 close(consumer_data->err_sock);
977 close(consumer_data->cmd_sock);
978 close(sock);
979
980 unlink(consumer_data->err_unix_sock_path);
981 unlink(consumer_data->cmd_unix_sock_path);
982 consumer_data->pid = 0;
983
984 lttng_poll_clean(&events);
985
986 return NULL;
987 }
988
989 /*
990 * This thread manage application communication.
991 */
992 static void *thread_manage_apps(void *data)
993 {
994 int i, ret, pollfd;
995 uint32_t revents, nb_fd;
996 struct ust_command ust_cmd;
997 struct lttng_poll_event events;
998
999 DBG("[thread] Manage application started");
1000
1001 rcu_register_thread();
1002 rcu_thread_online();
1003
1004 ret = create_thread_poll_set(&events, 2);
1005 if (ret < 0) {
1006 goto error;
1007 }
1008
1009 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1010 if (ret < 0) {
1011 goto error;
1012 }
1013
1014 while (1) {
1015 /* Zeroed the events structure */
1016 lttng_poll_reset(&events);
1017
1018 nb_fd = LTTNG_POLL_GETNB(&events);
1019
1020 DBG("Apps thread polling on %d fds", nb_fd);
1021
1022 /* Inifinite blocking call, waiting for transmission */
1023 ret = lttng_poll_wait(&events, -1);
1024 if (ret < 0) {
1025 goto error;
1026 }
1027
1028 for (i = 0; i < nb_fd; i++) {
1029 /* Fetch once the poll data */
1030 revents = LTTNG_POLL_GETEV(&events, i);
1031 pollfd = LTTNG_POLL_GETFD(&events, i);
1032
1033 /* Thread quit pipe has been closed. Killing thread. */
1034 ret = check_thread_quit_pipe(pollfd, revents);
1035 if (ret) {
1036 goto error;
1037 }
1038
1039 /* Inspect the apps cmd pipe */
1040 if (pollfd == apps_cmd_pipe[0]) {
1041 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1042 ERR("Apps command pipe error");
1043 goto error;
1044 } else if (revents & LPOLLIN) {
1045 /* Empty pipe */
1046 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1047 if (ret < 0 || ret < sizeof(ust_cmd)) {
1048 perror("read apps cmd pipe");
1049 goto error;
1050 }
1051
1052 /* Register applicaton to the session daemon */
1053 ret = ust_app_register(&ust_cmd.reg_msg,
1054 ust_cmd.sock);
1055 if (ret < 0) {
1056 /* Only critical ENOMEM error can be returned here */
1057 goto error;
1058 }
1059
1060 /*
1061 * Add channel(s) and event(s) to newly registered apps
1062 * from lttng global UST domain.
1063 */
1064 update_ust_app(ust_cmd.sock);
1065
1066 ret = ustctl_register_done(ust_cmd.sock);
1067 if (ret < 0) {
1068 /*
1069 * If the registration is not possible, we simply
1070 * unregister the apps and continue
1071 */
1072 ust_app_unregister(ust_cmd.sock);
1073 } else {
1074 /*
1075 * We just need here to monitor the close of the UST
1076 * socket and poll set monitor those by default.
1077 */
1078 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1079 if (ret < 0) {
1080 goto error;
1081 }
1082
1083 DBG("Apps with sock %d added to poll set",
1084 ust_cmd.sock);
1085 }
1086
1087 break;
1088 }
1089 } else {
1090 /*
1091 * At this point, we know that a registered application made
1092 * the event at poll_wait.
1093 */
1094 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1095 /* Removing from the poll set */
1096 ret = lttng_poll_del(&events, pollfd);
1097 if (ret < 0) {
1098 goto error;
1099 }
1100
1101 /* Socket closed */
1102 ust_app_unregister(pollfd);
1103 break;
1104 }
1105 }
1106 }
1107 }
1108
1109 error:
1110 DBG("Application communication apps dying");
1111 close(apps_cmd_pipe[0]);
1112 close(apps_cmd_pipe[1]);
1113
1114 lttng_poll_clean(&events);
1115
1116 rcu_thread_offline();
1117 rcu_unregister_thread();
1118 return NULL;
1119 }
1120
1121 /*
1122 * Dispatch request from the registration threads to the application
1123 * communication thread.
1124 */
1125 static void *thread_dispatch_ust_registration(void *data)
1126 {
1127 int ret;
1128 struct cds_wfq_node *node;
1129 struct ust_command *ust_cmd = NULL;
1130
1131 DBG("[thread] Dispatch UST command started");
1132
1133 while (!dispatch_thread_exit) {
1134 /* Atomically prepare the queue futex */
1135 futex_nto1_prepare(&ust_cmd_queue.futex);
1136
1137 do {
1138 /* Dequeue command for registration */
1139 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1140 if (node == NULL) {
1141 DBG("Woken up but nothing in the UST command queue");
1142 /* Continue thread execution */
1143 break;
1144 }
1145
1146 ust_cmd = caa_container_of(node, struct ust_command, node);
1147
1148 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1149 " gid:%d sock:%d name:%s (version %d.%d)",
1150 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1151 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1152 ust_cmd->sock, ust_cmd->reg_msg.name,
1153 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1154 /*
1155 * Inform apps thread of the new application registration. This
1156 * call is blocking so we can be assured that the data will be read
1157 * at some point in time or wait to the end of the world :)
1158 */
1159 ret = write(apps_cmd_pipe[1], ust_cmd,
1160 sizeof(struct ust_command));
1161 if (ret < 0) {
1162 perror("write apps cmd pipe");
1163 if (errno == EBADF) {
1164 /*
1165 * We can't inform the application thread to process
1166 * registration. We will exit or else application
1167 * registration will not occur and tracing will never
1168 * start.
1169 */
1170 goto error;
1171 }
1172 }
1173 free(ust_cmd);
1174 } while (node != NULL);
1175
1176 /* Futex wait on queue. Blocking call on futex() */
1177 futex_nto1_wait(&ust_cmd_queue.futex);
1178 }
1179
1180 error:
1181 DBG("Dispatch thread dying");
1182 return NULL;
1183 }
1184
1185 /*
1186 * This thread manage application registration.
1187 */
1188 static void *thread_registration_apps(void *data)
1189 {
1190 int sock = 0, i, ret, pollfd;
1191 uint32_t revents, nb_fd;
1192 struct lttng_poll_event events;
1193 /*
1194 * Get allocated in this thread, enqueued to a global queue, dequeued and
1195 * freed in the manage apps thread.
1196 */
1197 struct ust_command *ust_cmd = NULL;
1198
1199 DBG("[thread] Manage application registration started");
1200
1201 ret = lttcomm_listen_unix_sock(apps_sock);
1202 if (ret < 0) {
1203 goto error;
1204 }
1205
1206 /*
1207 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1208 * more will be added to this poll set.
1209 */
1210 ret = create_thread_poll_set(&events, 2);
1211 if (ret < 0) {
1212 goto error;
1213 }
1214
1215 /* Add the application registration socket */
1216 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1217 if (ret < 0) {
1218 goto error;
1219 }
1220
1221 /* Notify all applications to register */
1222 ret = notify_ust_apps(1);
1223 if (ret < 0) {
1224 ERR("Failed to notify applications or create the wait shared memory.\n"
1225 "Execution continues but there might be problem for already\n"
1226 "running applications that wishes to register.");
1227 }
1228
1229 while (1) {
1230 DBG("Accepting application registration");
1231
1232 nb_fd = LTTNG_POLL_GETNB(&events);
1233
1234 /* Inifinite blocking call, waiting for transmission */
1235 ret = lttng_poll_wait(&events, -1);
1236 if (ret < 0) {
1237 goto error;
1238 }
1239
1240 for (i = 0; i < nb_fd; i++) {
1241 /* Fetch once the poll data */
1242 revents = LTTNG_POLL_GETEV(&events, i);
1243 pollfd = LTTNG_POLL_GETFD(&events, i);
1244
1245 /* Thread quit pipe has been closed. Killing thread. */
1246 ret = check_thread_quit_pipe(pollfd, revents);
1247 if (ret) {
1248 goto error;
1249 }
1250
1251 /* Event on the registration socket */
1252 if (pollfd == apps_sock) {
1253 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1254 ERR("Register apps socket poll error");
1255 goto error;
1256 } else if (revents & LPOLLIN) {
1257 sock = lttcomm_accept_unix_sock(apps_sock);
1258 if (sock < 0) {
1259 goto error;
1260 }
1261
1262 /* Create UST registration command for enqueuing */
1263 ust_cmd = malloc(sizeof(struct ust_command));
1264 if (ust_cmd == NULL) {
1265 perror("ust command malloc");
1266 goto error;
1267 }
1268
1269 /*
1270 * Using message-based transmissions to ensure we don't
1271 * have to deal with partially received messages.
1272 */
1273 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1274 sizeof(struct ust_register_msg));
1275 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1276 if (ret < 0) {
1277 perror("lttcomm_recv_unix_sock register apps");
1278 } else {
1279 ERR("Wrong size received on apps register");
1280 }
1281 free(ust_cmd);
1282 close(sock);
1283 continue;
1284 }
1285
1286 ust_cmd->sock = sock;
1287
1288 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1289 " gid:%d sock:%d name:%s (version %d.%d)",
1290 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1291 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1292 ust_cmd->sock, ust_cmd->reg_msg.name,
1293 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1294
1295 /*
1296 * Lock free enqueue the registration request. The red pill
1297 * has been taken! This apps will be part of the *system*.
1298 */
1299 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1300
1301 /*
1302 * Wake the registration queue futex. Implicit memory
1303 * barrier with the exchange in cds_wfq_enqueue.
1304 */
1305 futex_nto1_wake(&ust_cmd_queue.futex);
1306 }
1307 }
1308 }
1309 }
1310
1311 error:
1312 DBG("UST Registration thread dying");
1313
1314 /* Notify that the registration thread is gone */
1315 notify_ust_apps(0);
1316
1317 close(apps_sock);
1318 close(sock);
1319 unlink(apps_unix_sock_path);
1320
1321 lttng_poll_clean(&events);
1322
1323 return NULL;
1324 }
1325
1326 /*
1327 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1328 * exec or it will fails.
1329 */
1330 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1331 {
1332 int ret;
1333 struct timespec timeout;
1334
1335 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1336 timeout.tv_nsec = 0;
1337
1338 /* Setup semaphore */
1339 ret = sem_init(&consumer_data->sem, 0, 0);
1340 if (ret < 0) {
1341 PERROR("sem_init consumer semaphore");
1342 goto error;
1343 }
1344
1345 ret = pthread_create(&consumer_data->thread, NULL,
1346 thread_manage_consumer, consumer_data);
1347 if (ret != 0) {
1348 PERROR("pthread_create consumer");
1349 ret = -1;
1350 goto error;
1351 }
1352
1353 /* Get time for sem_timedwait absolute timeout */
1354 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1355 if (ret < 0) {
1356 PERROR("clock_gettime spawn consumer");
1357 /* Infinite wait for the kconsumerd thread to be ready */
1358 ret = sem_wait(&consumer_data->sem);
1359 } else {
1360 /* Normal timeout if the gettime was successful */
1361 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1362 ret = sem_timedwait(&consumer_data->sem, &timeout);
1363 }
1364
1365 if (ret < 0) {
1366 if (errno == ETIMEDOUT) {
1367 /*
1368 * Call has timed out so we kill the kconsumerd_thread and return
1369 * an error.
1370 */
1371 ERR("The consumer thread was never ready. Killing it");
1372 ret = pthread_cancel(consumer_data->thread);
1373 if (ret < 0) {
1374 PERROR("pthread_cancel consumer thread");
1375 }
1376 } else {
1377 PERROR("semaphore wait failed consumer thread");
1378 }
1379 goto error;
1380 }
1381
1382 pthread_mutex_lock(&consumer_data->pid_mutex);
1383 if (consumer_data->pid == 0) {
1384 ERR("Kconsumerd did not start");
1385 pthread_mutex_unlock(&consumer_data->pid_mutex);
1386 goto error;
1387 }
1388 pthread_mutex_unlock(&consumer_data->pid_mutex);
1389
1390 return 0;
1391
1392 error:
1393 return ret;
1394 }
1395
1396 /*
1397 * Join consumer thread
1398 */
1399 static int join_consumer_thread(struct consumer_data *consumer_data)
1400 {
1401 void *status;
1402 int ret;
1403
1404 if (consumer_data->pid != 0) {
1405 ret = kill(consumer_data->pid, SIGTERM);
1406 if (ret) {
1407 ERR("Error killing consumer daemon");
1408 return ret;
1409 }
1410 return pthread_join(consumer_data->thread, &status);
1411 } else {
1412 return 0;
1413 }
1414 }
1415
1416 /*
1417 * Fork and exec a consumer daemon (consumerd).
1418 *
1419 * Return pid if successful else -1.
1420 */
1421 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1422 {
1423 int ret;
1424 pid_t pid;
1425 const char *verbosity;
1426
1427 DBG("Spawning consumerd");
1428
1429 pid = fork();
1430 if (pid == 0) {
1431 /*
1432 * Exec consumerd.
1433 */
1434 if (opt_verbose > 1 || opt_verbose_consumer) {
1435 verbosity = "--verbose";
1436 } else {
1437 verbosity = "--quiet";
1438 }
1439 switch (consumer_data->type) {
1440 case LTTNG_CONSUMER_KERNEL:
1441 execl(INSTALL_BIN_PATH "/lttng-consumerd",
1442 "lttng-consumerd", verbosity, "-k", NULL);
1443 break;
1444 case LTTNG_CONSUMER_UST:
1445 execl(INSTALL_BIN_PATH "/lttng-consumerd",
1446 "lttng-consumerd", verbosity, "-u", NULL);
1447 break;
1448 default:
1449 perror("unknown consumer type");
1450 exit(EXIT_FAILURE);
1451 }
1452 if (errno != 0) {
1453 perror("kernel start consumer exec");
1454 }
1455 exit(EXIT_FAILURE);
1456 } else if (pid > 0) {
1457 ret = pid;
1458 } else {
1459 perror("start consumer fork");
1460 ret = -errno;
1461 }
1462 return ret;
1463 }
1464
1465 /*
1466 * Spawn the consumerd daemon and session daemon thread.
1467 */
1468 static int start_consumerd(struct consumer_data *consumer_data)
1469 {
1470 int ret;
1471
1472 pthread_mutex_lock(&consumer_data->pid_mutex);
1473 if (consumer_data->pid != 0) {
1474 pthread_mutex_unlock(&consumer_data->pid_mutex);
1475 goto end;
1476 }
1477
1478 ret = spawn_consumerd(consumer_data);
1479 if (ret < 0) {
1480 ERR("Spawning consumerd failed");
1481 pthread_mutex_unlock(&consumer_data->pid_mutex);
1482 goto error;
1483 }
1484
1485 /* Setting up the consumer_data pid */
1486 consumer_data->pid = ret;
1487 DBG2("Consumer pid %d", consumer_data->pid);
1488 pthread_mutex_unlock(&consumer_data->pid_mutex);
1489
1490 DBG2("Spawning consumer control thread");
1491 ret = spawn_consumer_thread(consumer_data);
1492 if (ret < 0) {
1493 ERR("Fatal error spawning consumer control thread");
1494 goto error;
1495 }
1496
1497 end:
1498 return 0;
1499
1500 error:
1501 return ret;
1502 }
1503
1504 /*
1505 * modprobe_kernel_modules
1506 */
1507 static int modprobe_kernel_modules(void)
1508 {
1509 int ret = 0, i;
1510 char modprobe[256];
1511
1512 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1513 ret = snprintf(modprobe, sizeof(modprobe),
1514 "/sbin/modprobe %s%s",
1515 kernel_modules_list[i].required ? "" : "-q ",
1516 kernel_modules_list[i].name);
1517 if (ret < 0) {
1518 perror("snprintf modprobe");
1519 goto error;
1520 }
1521 modprobe[sizeof(modprobe) - 1] = '\0';
1522 ret = system(modprobe);
1523 if (ret == -1) {
1524 ERR("Unable to launch modprobe for module %s",
1525 kernel_modules_list[i].name);
1526 } else if (kernel_modules_list[i].required
1527 && WEXITSTATUS(ret) != 0) {
1528 ERR("Unable to load module %s",
1529 kernel_modules_list[i].name);
1530 } else {
1531 DBG("Modprobe successfully %s",
1532 kernel_modules_list[i].name);
1533 }
1534 }
1535
1536 error:
1537 return ret;
1538 }
1539
1540 /*
1541 * mount_debugfs
1542 */
1543 static int mount_debugfs(char *path)
1544 {
1545 int ret;
1546 char *type = "debugfs";
1547
1548 ret = mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1549 if (ret < 0) {
1550 PERROR("Cannot create debugfs path");
1551 goto error;
1552 }
1553
1554 ret = mount(type, path, type, 0, NULL);
1555 if (ret < 0) {
1556 PERROR("Cannot mount debugfs");
1557 goto error;
1558 }
1559
1560 DBG("Mounted debugfs successfully at %s", path);
1561
1562 error:
1563 return ret;
1564 }
1565
1566 /*
1567 * Setup necessary data for kernel tracer action.
1568 */
1569 static void init_kernel_tracer(void)
1570 {
1571 int ret;
1572 char *proc_mounts = "/proc/mounts";
1573 char line[256];
1574 char *debugfs_path = NULL, *lttng_path = NULL;
1575 FILE *fp;
1576
1577 /* Detect debugfs */
1578 fp = fopen(proc_mounts, "r");
1579 if (fp == NULL) {
1580 ERR("Unable to probe %s", proc_mounts);
1581 goto error;
1582 }
1583
1584 while (fgets(line, sizeof(line), fp) != NULL) {
1585 if (strstr(line, "debugfs") != NULL) {
1586 /* Remove first string */
1587 strtok(line, " ");
1588 /* Dup string here so we can reuse line later on */
1589 debugfs_path = strdup(strtok(NULL, " "));
1590 DBG("Got debugfs path : %s", debugfs_path);
1591 break;
1592 }
1593 }
1594
1595 fclose(fp);
1596
1597 /* Mount debugfs if needded */
1598 if (debugfs_path == NULL) {
1599 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1600 if (ret < 0) {
1601 perror("asprintf debugfs path");
1602 goto error;
1603 }
1604 ret = mount_debugfs(debugfs_path);
1605 if (ret < 0) {
1606 perror("Cannot mount debugfs");
1607 goto error;
1608 }
1609 }
1610
1611 /* Modprobe lttng kernel modules */
1612 ret = modprobe_kernel_modules();
1613 if (ret < 0) {
1614 goto error;
1615 }
1616
1617 /* Setup lttng kernel path */
1618 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1619 if (ret < 0) {
1620 perror("asprintf lttng path");
1621 goto error;
1622 }
1623
1624 /* Open debugfs lttng */
1625 kernel_tracer_fd = open(lttng_path, O_RDWR);
1626 if (kernel_tracer_fd < 0) {
1627 DBG("Failed to open %s", lttng_path);
1628 goto error;
1629 }
1630
1631 free(lttng_path);
1632 free(debugfs_path);
1633 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1634 return;
1635
1636 error:
1637 if (lttng_path) {
1638 free(lttng_path);
1639 }
1640 if (debugfs_path) {
1641 free(debugfs_path);
1642 }
1643 WARN("No kernel tracer available");
1644 kernel_tracer_fd = 0;
1645 return;
1646 }
1647
1648 /*
1649 * Init tracing by creating trace directory and sending fds kernel consumer.
1650 */
1651 static int init_kernel_tracing(struct ltt_kernel_session *session)
1652 {
1653 int ret = 0;
1654
1655 if (session->consumer_fds_sent == 0) {
1656 /*
1657 * Assign default kernel consumer socket if no consumer assigned to the
1658 * kernel session. At this point, it's NOT suppose to be 0 but this is
1659 * an extra security check.
1660 */
1661 if (session->consumer_fd == 0) {
1662 session->consumer_fd = kconsumer_data.cmd_sock;
1663 }
1664
1665 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1666 if (ret < 0) {
1667 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1668 goto error;
1669 }
1670
1671 session->consumer_fds_sent = 1;
1672 }
1673
1674 error:
1675 return ret;
1676 }
1677
1678 /*
1679 * Create an UST session and add it to the session ust list.
1680 */
1681 static int create_ust_session(struct ltt_session *session,
1682 struct lttng_domain *domain)
1683 {
1684 int ret;
1685 unsigned int uid;
1686 struct ltt_ust_session *lus = NULL;
1687
1688 switch (domain->type) {
1689 case LTTNG_DOMAIN_UST:
1690 break;
1691 default:
1692 ret = LTTCOMM_UNKNOWN_DOMAIN;
1693 goto error;
1694 }
1695
1696 DBG("Creating UST session");
1697
1698 session_lock_list();
1699 uid = session_list_ptr->count;
1700 session_unlock_list();
1701
1702 lus = trace_ust_create_session(session->path, uid, domain);
1703 if (lus == NULL) {
1704 ret = LTTCOMM_UST_SESS_FAIL;
1705 goto error;
1706 }
1707
1708 ret = mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1709 geteuid(), allowed_group());
1710 if (ret < 0) {
1711 if (ret != -EEXIST) {
1712 ERR("Trace directory creation error");
1713 ret = LTTCOMM_UST_SESS_FAIL;
1714 goto error;
1715 }
1716 }
1717
1718 /* The domain type dictate different actions on session creation */
1719 switch (domain->type) {
1720 case LTTNG_DOMAIN_UST:
1721 /* No ustctl for the global UST domain */
1722 break;
1723 default:
1724 ERR("Unknown UST domain on create session %d", domain->type);
1725 goto error;
1726 }
1727 session->ust_session = lus;
1728
1729 return LTTCOMM_OK;
1730
1731 error:
1732 free(lus);
1733 return ret;
1734 }
1735
1736 /*
1737 * Create a kernel tracer session then create the default channel.
1738 */
1739 static int create_kernel_session(struct ltt_session *session)
1740 {
1741 int ret;
1742
1743 DBG("Creating kernel session");
1744
1745 ret = kernel_create_session(session, kernel_tracer_fd);
1746 if (ret < 0) {
1747 ret = LTTCOMM_KERN_SESS_FAIL;
1748 goto error;
1749 }
1750
1751 /* Set kernel consumer socket fd */
1752 if (kconsumer_data.cmd_sock) {
1753 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1754 }
1755
1756 ret = mkdir_recursive(session->kernel_session->trace_path,
1757 S_IRWXU | S_IRWXG, geteuid(), allowed_group());
1758 if (ret < 0) {
1759 if (ret != -EEXIST) {
1760 ERR("Trace directory creation error");
1761 goto error;
1762 }
1763 }
1764
1765 error:
1766 return ret;
1767 }
1768
1769 /*
1770 * Using the session list, filled a lttng_session array to send back to the
1771 * client for session listing.
1772 *
1773 * The session list lock MUST be acquired before calling this function. Use
1774 * session_lock_list() and session_unlock_list().
1775 */
1776 static void list_lttng_sessions(struct lttng_session *sessions)
1777 {
1778 int i = 0;
1779 struct ltt_session *session;
1780
1781 DBG("Getting all available session");
1782 /*
1783 * Iterate over session list and append data after the control struct in
1784 * the buffer.
1785 */
1786 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1787 strncpy(sessions[i].path, session->path, PATH_MAX);
1788 sessions[i].path[PATH_MAX - 1] = '\0';
1789 strncpy(sessions[i].name, session->name, NAME_MAX);
1790 sessions[i].name[NAME_MAX - 1] = '\0';
1791 i++;
1792 }
1793 }
1794
1795 /*
1796 * Fill lttng_channel array of all channels.
1797 */
1798 static void list_lttng_channels(struct ltt_session *session,
1799 struct lttng_channel *channels)
1800 {
1801 int i = 0;
1802 struct ltt_kernel_channel *kchan;
1803
1804 DBG("Listing channels for session %s", session->name);
1805
1806 /* Kernel channels */
1807 if (session->kernel_session != NULL) {
1808 cds_list_for_each_entry(kchan,
1809 &session->kernel_session->channel_list.head, list) {
1810 /* Copy lttng_channel struct to array */
1811 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
1812 channels[i].enabled = kchan->enabled;
1813 i++;
1814 }
1815 }
1816
1817 /* TODO: Missing UST listing */
1818 }
1819
1820 /*
1821 * Fill lttng_event array of all events in the channel.
1822 */
1823 static void list_lttng_events(struct ltt_kernel_channel *kchan,
1824 struct lttng_event *events)
1825 {
1826 /*
1827 * TODO: This is ONLY kernel. Need UST support.
1828 */
1829 int i = 0;
1830 struct ltt_kernel_event *event;
1831
1832 DBG("Listing events for channel %s", kchan->channel->name);
1833
1834 /* Kernel channels */
1835 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
1836 strncpy(events[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
1837 events[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
1838 events[i].enabled = event->enabled;
1839 switch (event->event->instrumentation) {
1840 case LTTNG_KERNEL_TRACEPOINT:
1841 events[i].type = LTTNG_EVENT_TRACEPOINT;
1842 break;
1843 case LTTNG_KERNEL_KPROBE:
1844 case LTTNG_KERNEL_KRETPROBE:
1845 events[i].type = LTTNG_EVENT_PROBE;
1846 memcpy(&events[i].attr.probe, &event->event->u.kprobe,
1847 sizeof(struct lttng_kernel_kprobe));
1848 break;
1849 case LTTNG_KERNEL_FUNCTION:
1850 events[i].type = LTTNG_EVENT_FUNCTION;
1851 memcpy(&events[i].attr.ftrace, &event->event->u.ftrace,
1852 sizeof(struct lttng_kernel_function));
1853 break;
1854 case LTTNG_KERNEL_NOOP:
1855 events[i].type = LTTNG_EVENT_NOOP;
1856 break;
1857 case LTTNG_KERNEL_SYSCALL:
1858 events[i].type = LTTNG_EVENT_SYSCALL;
1859 break;
1860 case LTTNG_KERNEL_ALL:
1861 assert(0);
1862 break;
1863 }
1864 i++;
1865 }
1866 }
1867
1868 /*
1869 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1870 */
1871 static int cmd_disable_channel(struct ltt_session *session,
1872 int domain, char *channel_name)
1873 {
1874 int ret;
1875
1876 switch (domain) {
1877 case LTTNG_DOMAIN_KERNEL:
1878 ret = channel_kernel_disable(session->kernel_session,
1879 channel_name);
1880 if (ret != LTTCOMM_OK) {
1881 goto error;
1882 }
1883
1884 kernel_wait_quiescent(kernel_tracer_fd);
1885 break;
1886 case LTTNG_DOMAIN_UST_PID:
1887 break;
1888 default:
1889 ret = LTTCOMM_UNKNOWN_DOMAIN;
1890 goto error;
1891 }
1892
1893 ret = LTTCOMM_OK;
1894
1895 error:
1896 return ret;
1897 }
1898
1899 /*
1900 * Copy channel from attributes and set it in the application channel list.
1901 */
1902 /*
1903 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
1904 struct lttng_channel *attr, struct ust_app *app)
1905 {
1906 int ret;
1907 struct ltt_ust_channel *uchan, *new_chan;
1908
1909 uchan = trace_ust_get_channel_by_key(usess->channels, attr->name);
1910 if (uchan == NULL) {
1911 ret = LTTCOMM_FATAL;
1912 goto error;
1913 }
1914
1915 new_chan = trace_ust_create_channel(attr, usess->path);
1916 if (new_chan == NULL) {
1917 PERROR("malloc ltt_ust_channel");
1918 ret = LTTCOMM_FATAL;
1919 goto error;
1920 }
1921
1922 ret = channel_ust_copy(new_chan, uchan);
1923 if (ret < 0) {
1924 ret = LTTCOMM_FATAL;
1925 goto error;
1926 }
1927
1928 error:
1929 return ret;
1930 }
1931 */
1932
1933 /*
1934 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1935 */
1936 static int cmd_enable_channel(struct ltt_session *session,
1937 struct lttng_domain *domain, struct lttng_channel *attr)
1938 {
1939 int ret;
1940 struct ltt_ust_session *usess = session->ust_session;
1941
1942 DBG("Enabling channel %s for session %s", session->name, attr->name);
1943
1944 switch (domain->type) {
1945 case LTTNG_DOMAIN_KERNEL:
1946 {
1947 struct ltt_kernel_channel *kchan;
1948
1949 kchan = trace_kernel_get_channel_by_name(attr->name,
1950 session->kernel_session);
1951 if (kchan == NULL) {
1952 ret = channel_kernel_create(session->kernel_session,
1953 attr, kernel_poll_pipe[1]);
1954 } else {
1955 ret = channel_kernel_enable(session->kernel_session, kchan);
1956 }
1957
1958 if (ret != LTTCOMM_OK) {
1959 goto error;
1960 }
1961
1962 kernel_wait_quiescent(kernel_tracer_fd);
1963 break;
1964 }
1965 case LTTNG_DOMAIN_UST:
1966 {
1967 struct ltt_ust_channel *uchan;
1968
1969 DBG2("Enabling channel for LTTNG_DOMAIN_UST");
1970
1971 /* Get channel in global UST domain HT */
1972 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1973 attr->name);
1974 if (uchan == NULL) {
1975 uchan = trace_ust_create_channel(attr, usess->pathname);
1976 if (uchan == NULL) {
1977 ret = LTTCOMM_UST_CHAN_FAIL;
1978 goto error;
1979 }
1980 rcu_read_lock();
1981 hashtable_add_unique(usess->domain_global.channels, &uchan->node);
1982 rcu_read_unlock();
1983 DBG2("UST channel %s added to global domain HT", attr->name);
1984 } else {
1985 ret = LTTCOMM_UST_CHAN_EXIST;
1986 goto error;
1987 }
1988
1989 /* Add channel to all registered applications */
1990 ret = ust_app_add_channel_all(usess, uchan);
1991 if (ret != LTTCOMM_OK) {
1992 goto error;
1993 }
1994
1995 break;
1996 }
1997 case LTTNG_DOMAIN_UST_PID:
1998 {
1999 /*
2000 int sock;
2001 struct ltt_ust_channel *uchan;
2002 struct ltt_ust_session *usess;
2003 struct ust_app *app;
2004
2005 usess = trace_ust_get_session_by_pid(&session->ust_session_list,
2006 domain->attr.pid);
2007 if (usess == NULL) {
2008 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2009 goto error;
2010 }
2011
2012 app = ust_app_get_by_pid(domain->attr.pid);
2013 if (app == NULL) {
2014 ret = LTTCOMM_APP_NOT_FOUND;
2015 goto error;
2016 }
2017 sock = app->sock;
2018
2019 uchan = trace_ust_get_channel_by_name(attr->name, usess);
2020 if (uchan == NULL) {
2021 ret = channel_ust_create(usess, attr, sock);
2022 } else {
2023 ret = channel_ust_enable(usess, uchan, sock);
2024 }
2025
2026 if (ret != LTTCOMM_OK) {
2027 goto error;
2028 }
2029
2030 ret = copy_ust_channel_to_app(usess, attr, app);
2031 if (ret != LTTCOMM_OK) {
2032 goto error;
2033 }
2034
2035 DBG("UST channel %s created for app sock %d with pid %d",
2036 attr->name, app->sock, domain->attr.pid);
2037 */
2038 ret = LTTCOMM_NOT_IMPLEMENTED;
2039 goto error;
2040 }
2041 default:
2042 ret = LTTCOMM_UNKNOWN_DOMAIN;
2043 goto error;
2044 }
2045
2046 ret = LTTCOMM_OK;
2047
2048 error:
2049 return ret;
2050 }
2051
2052 /*
2053 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2054 */
2055 static int cmd_disable_event(struct ltt_session *session, int domain,
2056 char *channel_name, char *event_name)
2057 {
2058 int ret;
2059
2060 switch (domain) {
2061 case LTTNG_DOMAIN_KERNEL:
2062 {
2063 struct ltt_kernel_channel *kchan;
2064
2065 kchan = trace_kernel_get_channel_by_name(channel_name,
2066 session->kernel_session);
2067 if (kchan == NULL) {
2068 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2069 goto error;
2070 }
2071
2072 ret = event_kernel_disable_tracepoint(session->kernel_session, kchan, event_name);
2073 if (ret != LTTCOMM_OK) {
2074 goto error;
2075 }
2076
2077 kernel_wait_quiescent(kernel_tracer_fd);
2078 break;
2079 }
2080 case LTTNG_DOMAIN_UST:
2081 case LTTNG_DOMAIN_UST_EXEC_NAME:
2082 case LTTNG_DOMAIN_UST_PID:
2083 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2084 default:
2085 /* TODO: Other UST domains */
2086 ret = LTTCOMM_NOT_IMPLEMENTED;
2087 goto error;
2088 }
2089
2090 ret = LTTCOMM_OK;
2091
2092 error:
2093 return ret;
2094 }
2095
2096 /*
2097 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2098 */
2099 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2100 char *channel_name)
2101 {
2102 int ret;
2103 struct ltt_kernel_channel *kchan;
2104
2105 switch (domain) {
2106 case LTTNG_DOMAIN_KERNEL:
2107 kchan = trace_kernel_get_channel_by_name(channel_name,
2108 session->kernel_session);
2109 if (kchan == NULL) {
2110 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2111 goto error;
2112 }
2113
2114 ret = event_kernel_disable_all(session->kernel_session, kchan);
2115 if (ret != LTTCOMM_OK) {
2116 goto error;
2117 }
2118
2119 kernel_wait_quiescent(kernel_tracer_fd);
2120 break;
2121 default:
2122 /* TODO: Userspace tracing */
2123 ret = LTTCOMM_NOT_IMPLEMENTED;
2124 goto error;
2125 }
2126
2127 ret = LTTCOMM_OK;
2128
2129 error:
2130 return ret;
2131 }
2132
2133 /*
2134 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2135 */
2136 static int cmd_add_context(struct ltt_session *session, int domain,
2137 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2138 {
2139 int ret;
2140
2141 switch (domain) {
2142 case LTTNG_DOMAIN_KERNEL:
2143 /* Add kernel context to kernel tracer */
2144 ret = context_kernel_add(session->kernel_session, ctx,
2145 event_name, channel_name);
2146 if (ret != LTTCOMM_OK) {
2147 goto error;
2148 }
2149 break;
2150 case LTTNG_DOMAIN_UST:
2151 {
2152 /*
2153 struct ltt_ust_session *usess;
2154
2155 cds_list_for_each_entry(usess, &session->ust_session_list.head, list) {
2156 ret = context_ust_add(usess, ctx,
2157 event_name, channel_name, domain);
2158 if (ret != LTTCOMM_OK) {
2159 goto error;
2160 }
2161 }
2162 break;
2163 */
2164 }
2165 default:
2166 /* TODO: UST other domains */
2167 ret = LTTCOMM_NOT_IMPLEMENTED;
2168 goto error;
2169 }
2170
2171 ret = LTTCOMM_OK;
2172
2173 error:
2174 return ret;
2175 }
2176
2177 /*
2178 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2179 */
2180 static int cmd_enable_event(struct ltt_session *session, int domain,
2181 char *channel_name, struct lttng_event *event)
2182 {
2183 int ret;
2184 struct lttng_channel *attr;
2185 struct ltt_ust_session *usess = session->ust_session;
2186
2187 switch (domain) {
2188 case LTTNG_DOMAIN_KERNEL:
2189 {
2190 struct ltt_kernel_channel *kchan;
2191
2192 kchan = trace_kernel_get_channel_by_name(channel_name,
2193 session->kernel_session);
2194 if (kchan == NULL) {
2195 attr = channel_new_default_attr(domain);
2196 if (attr == NULL) {
2197 ret = LTTCOMM_FATAL;
2198 goto error;
2199 }
2200 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2201
2202 /* This call will notify the kernel thread */
2203 ret = channel_kernel_create(session->kernel_session,
2204 attr, kernel_poll_pipe[1]);
2205 if (ret != LTTCOMM_OK) {
2206 goto error;
2207 }
2208 }
2209
2210 /* Get the newly created kernel channel pointer */
2211 kchan = trace_kernel_get_channel_by_name(channel_name,
2212 session->kernel_session);
2213 if (kchan == NULL) {
2214 /* This sould not happen... */
2215 ret = LTTCOMM_FATAL;
2216 goto error;
2217 }
2218
2219 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2220 event);
2221 if (ret != LTTCOMM_OK) {
2222 goto error;
2223 }
2224
2225 kernel_wait_quiescent(kernel_tracer_fd);
2226 break;
2227 }
2228 case LTTNG_DOMAIN_UST:
2229 {
2230 struct ltt_ust_channel *uchan;
2231 struct ltt_ust_event *uevent;
2232
2233 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2234 channel_name);
2235 if (uchan == NULL) {
2236 /* TODO: Create default channel */
2237 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2238 goto error;
2239 }
2240
2241 uevent = trace_ust_find_event_by_name(uchan->events, event->name);
2242 if (uevent == NULL) {
2243 uevent = trace_ust_create_event(event);
2244 if (uevent == NULL) {
2245 ret = LTTCOMM_FATAL;
2246 goto error;
2247 }
2248 }
2249
2250 ret = ust_app_add_event_all(usess, uchan, uevent);
2251 if (ret < 0) {
2252 ret = LTTCOMM_UST_ENABLE_FAIL;
2253 goto error;
2254 }
2255
2256 rcu_read_lock();
2257 hashtable_add_unique(uchan->events, &uevent->node);
2258 rcu_read_unlock();
2259 break;
2260 }
2261 case LTTNG_DOMAIN_UST_EXEC_NAME:
2262 case LTTNG_DOMAIN_UST_PID:
2263 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2264 default:
2265 ret = LTTCOMM_NOT_IMPLEMENTED;
2266 goto error;
2267 }
2268
2269 ret = LTTCOMM_OK;
2270
2271 error:
2272 return ret;
2273 }
2274
2275 /*
2276 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2277 */
2278 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2279 char *channel_name, int event_type)
2280 {
2281 int ret;
2282 struct ltt_kernel_channel *kchan;
2283
2284 switch (domain) {
2285 case LTTNG_DOMAIN_KERNEL:
2286 kchan = trace_kernel_get_channel_by_name(channel_name,
2287 session->kernel_session);
2288 if (kchan == NULL) {
2289 /* This call will notify the kernel thread */
2290 ret = channel_kernel_create(session->kernel_session, NULL,
2291 kernel_poll_pipe[1]);
2292 if (ret != LTTCOMM_OK) {
2293 goto error;
2294 }
2295 }
2296
2297 /* Get the newly created kernel channel pointer */
2298 kchan = trace_kernel_get_channel_by_name(channel_name,
2299 session->kernel_session);
2300 if (kchan == NULL) {
2301 /* This sould not happen... */
2302 ret = LTTCOMM_FATAL;
2303 goto error;
2304 }
2305
2306 switch (event_type) {
2307 case LTTNG_KERNEL_SYSCALL:
2308 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2309 kchan, kernel_tracer_fd);
2310 break;
2311 case LTTNG_KERNEL_TRACEPOINT:
2312 /*
2313 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2314 * events already registered to the channel.
2315 */
2316 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2317 kchan, kernel_tracer_fd);
2318 break;
2319 case LTTNG_KERNEL_ALL:
2320 /* Enable syscalls and tracepoints */
2321 ret = event_kernel_enable_all(session->kernel_session,
2322 kchan, kernel_tracer_fd);
2323 break;
2324 default:
2325 ret = LTTCOMM_KERN_ENABLE_FAIL;
2326 goto error;
2327 }
2328 if (ret != LTTCOMM_OK) {
2329 goto error;
2330 }
2331
2332 kernel_wait_quiescent(kernel_tracer_fd);
2333 break;
2334 default:
2335 /* TODO: Userspace tracing */
2336 ret = LTTCOMM_NOT_IMPLEMENTED;
2337 goto error;
2338 }
2339
2340 ret = LTTCOMM_OK;
2341
2342 error:
2343 return ret;
2344 }
2345
2346 /*
2347 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2348 */
2349 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2350 {
2351 int ret;
2352 ssize_t nb_events = 0;
2353
2354 switch (domain) {
2355 case LTTNG_DOMAIN_KERNEL:
2356 nb_events = kernel_list_events(kernel_tracer_fd, events);
2357 if (nb_events < 0) {
2358 ret = LTTCOMM_KERN_LIST_FAIL;
2359 goto error;
2360 }
2361 break;
2362 default:
2363 /* TODO: Userspace listing */
2364 ret = LTTCOMM_NOT_IMPLEMENTED;
2365 goto error;
2366 }
2367
2368 return nb_events;
2369
2370 error:
2371 /* Return negative value to differentiate return code */
2372 return -ret;
2373 }
2374
2375 /*
2376 * Command LTTNG_START_TRACE processed by the client thread.
2377 */
2378 static int cmd_start_trace(struct ltt_session *session)
2379 {
2380 int ret;
2381 struct ltt_kernel_session *ksession;
2382 struct ltt_ust_session *usess = session->ust_session;
2383
2384 /* Short cut */
2385 ksession = session->kernel_session;
2386
2387 /* Kernel tracing */
2388 if (ksession != NULL) {
2389 struct ltt_kernel_channel *kchan;
2390
2391 /* Open kernel metadata */
2392 if (ksession->metadata == NULL) {
2393 ret = kernel_open_metadata(ksession, ksession->trace_path);
2394 if (ret < 0) {
2395 ret = LTTCOMM_KERN_META_FAIL;
2396 goto error;
2397 }
2398 }
2399
2400 /* Open kernel metadata stream */
2401 if (ksession->metadata_stream_fd == 0) {
2402 ret = kernel_open_metadata_stream(ksession);
2403 if (ret < 0) {
2404 ERR("Kernel create metadata stream failed");
2405 ret = LTTCOMM_KERN_STREAM_FAIL;
2406 goto error;
2407 }
2408 }
2409
2410 /* For each channel */
2411 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2412 if (kchan->stream_count == 0) {
2413 ret = kernel_open_channel_stream(kchan);
2414 if (ret < 0) {
2415 ret = LTTCOMM_KERN_STREAM_FAIL;
2416 goto error;
2417 }
2418 /* Update the stream global counter */
2419 ksession->stream_count_global += ret;
2420 }
2421 }
2422
2423 /* Setup kernel consumer socket and send fds to it */
2424 ret = init_kernel_tracing(ksession);
2425 if (ret < 0) {
2426 ret = LTTCOMM_KERN_START_FAIL;
2427 goto error;
2428 }
2429
2430 /* This start the kernel tracing */
2431 ret = kernel_start_session(ksession);
2432 if (ret < 0) {
2433 ret = LTTCOMM_KERN_START_FAIL;
2434 goto error;
2435 }
2436
2437 /* Quiescent wait after starting trace */
2438 kernel_wait_quiescent(kernel_tracer_fd);
2439 }
2440
2441 /* Flag session that trace should start automatically */
2442 usess->start_trace = 1;
2443
2444 ret = ust_app_start_trace_all(usess);
2445 if (ret < 0) {
2446 ret = LTTCOMM_UST_START_FAIL;
2447 goto error;
2448 }
2449
2450 ret = LTTCOMM_OK;
2451
2452 error:
2453 return ret;
2454 }
2455
2456 /*
2457 * Command LTTNG_STOP_TRACE processed by the client thread.
2458 */
2459 static int cmd_stop_trace(struct ltt_session *session)
2460 {
2461 int ret;
2462 struct ltt_kernel_channel *kchan;
2463 struct ltt_kernel_session *ksession;
2464 //struct ltt_ust_session *usess;
2465 //struct ltt_ust_channel *ustchan;
2466
2467 /* Short cut */
2468 ksession = session->kernel_session;
2469
2470 /* Kernel tracer */
2471 if (ksession != NULL) {
2472 DBG("Stop kernel tracing");
2473
2474 /* Flush all buffers before stopping */
2475 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2476 if (ret < 0) {
2477 ERR("Kernel metadata flush failed");
2478 }
2479
2480 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2481 ret = kernel_flush_buffer(kchan);
2482 if (ret < 0) {
2483 ERR("Kernel flush buffer error");
2484 }
2485 }
2486
2487 ret = kernel_stop_session(ksession);
2488 if (ret < 0) {
2489 ret = LTTCOMM_KERN_STOP_FAIL;
2490 goto error;
2491 }
2492
2493 kernel_wait_quiescent(kernel_tracer_fd);
2494 }
2495
2496 #ifdef DISABLE
2497 /* Stop each UST session */
2498 DBG("Stop UST tracing");
2499 cds_list_for_each_entry(usess, &session->ust_session_list.head, list) {
2500 /* Flush all buffers before stopping */
2501 ret = ustctl_flush_buffer(usess->sock, usess->metadata->obj);
2502 if (ret < 0) {
2503 ERR("UST metadata flush failed");
2504 }
2505
2506 cds_list_for_each_entry(ustchan, &usess->channels.head, list) {
2507 ret = ustctl_flush_buffer(usess->sock, ustchan->obj);
2508 if (ret < 0) {
2509 ERR("UST flush buffer error");
2510 }
2511 }
2512
2513 ret = ustctl_stop_session(usess->sock, usess->handle);
2514 if (ret < 0) {
2515 ret = LTTCOMM_KERN_STOP_FAIL;
2516 goto error;
2517 }
2518
2519 ustctl_wait_quiescent(usess->sock);
2520 }
2521 #endif
2522
2523 ret = LTTCOMM_OK;
2524
2525 error:
2526 return ret;
2527 }
2528
2529 /*
2530 * Command LTTNG_CREATE_SESSION processed by the client thread.
2531 */
2532 static int cmd_create_session(char *name, char *path)
2533 {
2534 int ret;
2535
2536 ret = session_create(name, path);
2537 if (ret != LTTCOMM_OK) {
2538 goto error;
2539 }
2540
2541 ret = LTTCOMM_OK;
2542
2543 error:
2544 return ret;
2545 }
2546
2547 /*
2548 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2549 */
2550 static int cmd_destroy_session(struct ltt_session *session, char *name)
2551 {
2552 int ret;
2553
2554 /* Clean kernel session teardown */
2555 teardown_kernel_session(session);
2556
2557 /*
2558 * Must notify the kernel thread here to update it's poll setin order
2559 * to remove the channel(s)' fd just destroyed.
2560 */
2561 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2562 if (ret < 0) {
2563 perror("write kernel poll pipe");
2564 }
2565
2566 ret = session_destroy(session);
2567
2568 return ret;
2569 }
2570
2571 /*
2572 * Command LTTNG_CALIBRATE processed by the client thread.
2573 */
2574 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2575 {
2576 int ret;
2577
2578 switch (domain) {
2579 case LTTNG_DOMAIN_KERNEL:
2580 {
2581 struct lttng_kernel_calibrate kcalibrate;
2582
2583 kcalibrate.type = calibrate->type;
2584 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2585 if (ret < 0) {
2586 ret = LTTCOMM_KERN_ENABLE_FAIL;
2587 goto error;
2588 }
2589 break;
2590 }
2591 default:
2592 /* TODO: Userspace tracing */
2593 ret = LTTCOMM_NOT_IMPLEMENTED;
2594 goto error;
2595 }
2596
2597 ret = LTTCOMM_OK;
2598
2599 error:
2600 return ret;
2601 }
2602
2603 /*
2604 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2605 */
2606 static int cmd_register_consumer(struct ltt_session *session, int domain,
2607 char *sock_path)
2608 {
2609 int ret, sock;
2610
2611 switch (domain) {
2612 case LTTNG_DOMAIN_KERNEL:
2613 /* Can't register a consumer if there is already one */
2614 if (session->kernel_session->consumer_fd != 0) {
2615 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2616 goto error;
2617 }
2618
2619 sock = lttcomm_connect_unix_sock(sock_path);
2620 if (sock < 0) {
2621 ret = LTTCOMM_CONNECT_FAIL;
2622 goto error;
2623 }
2624
2625 session->kernel_session->consumer_fd = sock;
2626 break;
2627 default:
2628 /* TODO: Userspace tracing */
2629 ret = LTTCOMM_NOT_IMPLEMENTED;
2630 goto error;
2631 }
2632
2633 ret = LTTCOMM_OK;
2634
2635 error:
2636 return ret;
2637 }
2638
2639 /*
2640 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2641 */
2642 static ssize_t cmd_list_domains(struct ltt_session *session,
2643 struct lttng_domain **domains)
2644 {
2645 int ret;
2646 ssize_t nb_dom = 0;
2647
2648 if (session->kernel_session != NULL) {
2649 nb_dom++;
2650 }
2651
2652 /* TODO: User-space tracer domain support */
2653
2654 *domains = malloc(nb_dom * sizeof(struct lttng_domain));
2655 if (*domains == NULL) {
2656 ret = -LTTCOMM_FATAL;
2657 goto error;
2658 }
2659
2660 (*domains)[0].type = LTTNG_DOMAIN_KERNEL;
2661
2662 return nb_dom;
2663
2664 error:
2665 return ret;
2666 }
2667
2668 /*
2669 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2670 */
2671 static ssize_t cmd_list_channels(struct ltt_session *session,
2672 struct lttng_channel **channels)
2673 {
2674 int ret;
2675 ssize_t nb_chan = 0;
2676
2677 if (session->kernel_session != NULL) {
2678 nb_chan += session->kernel_session->channel_count;
2679 }
2680
2681 *channels = malloc(nb_chan * sizeof(struct lttng_channel));
2682 if (*channels == NULL) {
2683 ret = -LTTCOMM_FATAL;
2684 goto error;
2685 }
2686
2687 list_lttng_channels(session, *channels);
2688
2689 /* TODO UST support */
2690
2691 return nb_chan;
2692
2693 error:
2694 return ret;
2695 }
2696
2697 /*
2698 * Command LTTNG_LIST_EVENTS processed by the client thread.
2699 */
2700 static ssize_t cmd_list_events(struct ltt_session *session,
2701 char *channel_name, struct lttng_event **events)
2702 {
2703 int ret;
2704 ssize_t nb_event = 0;
2705 struct ltt_kernel_channel *kchan = NULL;
2706
2707 if (session->kernel_session != NULL) {
2708 kchan = trace_kernel_get_channel_by_name(channel_name,
2709 session->kernel_session);
2710 if (kchan == NULL) {
2711 ret = -LTTCOMM_KERN_CHAN_NOT_FOUND;
2712 goto error;
2713 }
2714 nb_event += kchan->event_count;
2715 }
2716
2717 *events = malloc(nb_event * sizeof(struct lttng_event));
2718 if (*events == NULL) {
2719 ret = -LTTCOMM_FATAL;
2720 goto error;
2721 }
2722
2723 list_lttng_events(kchan, *events);
2724
2725 /* TODO: User-space tracer support */
2726
2727 return nb_event;
2728
2729 error:
2730 return ret;
2731 }
2732
2733 /*
2734 * Process the command requested by the lttng client within the command
2735 * context structure. This function make sure that the return structure (llm)
2736 * is set and ready for transmission before returning.
2737 *
2738 * Return any error encountered or 0 for success.
2739 */
2740 static int process_client_msg(struct command_ctx *cmd_ctx)
2741 {
2742 int ret = LTTCOMM_OK;
2743 int need_tracing_session = 1;
2744
2745 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
2746
2747 /*
2748 * Check for command that don't needs to allocate a returned payload. We do
2749 * this here so we don't have to make the call for no payload at each
2750 * command.
2751 */
2752 switch(cmd_ctx->lsm->cmd_type) {
2753 case LTTNG_LIST_SESSIONS:
2754 case LTTNG_LIST_TRACEPOINTS:
2755 case LTTNG_LIST_DOMAINS:
2756 case LTTNG_LIST_CHANNELS:
2757 case LTTNG_LIST_EVENTS:
2758 break;
2759 default:
2760 /* Setup lttng message with no payload */
2761 ret = setup_lttng_msg(cmd_ctx, 0);
2762 if (ret < 0) {
2763 /* This label does not try to unlock the session */
2764 goto init_setup_error;
2765 }
2766 }
2767
2768 /* Commands that DO NOT need a session. */
2769 switch (cmd_ctx->lsm->cmd_type) {
2770 case LTTNG_CALIBRATE:
2771 case LTTNG_CREATE_SESSION:
2772 case LTTNG_LIST_SESSIONS:
2773 case LTTNG_LIST_TRACEPOINTS:
2774 need_tracing_session = 0;
2775 break;
2776 default:
2777 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
2778 session_lock_list();
2779 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
2780 session_unlock_list();
2781 if (cmd_ctx->session == NULL) {
2782 if (cmd_ctx->lsm->session.name != NULL) {
2783 ret = LTTCOMM_SESS_NOT_FOUND;
2784 } else {
2785 /* If no session name specified */
2786 ret = LTTCOMM_SELECT_SESS;
2787 }
2788 goto error;
2789 } else {
2790 /* Acquire lock for the session */
2791 session_lock(cmd_ctx->session);
2792 }
2793 break;
2794 }
2795
2796 /*
2797 * Check domain type for specific "pre-action".
2798 */
2799 switch (cmd_ctx->lsm->domain.type) {
2800 case LTTNG_DOMAIN_KERNEL:
2801 /* Kernel tracer check */
2802 if (kernel_tracer_fd == 0) {
2803 /* Basically, load kernel tracer modules */
2804 init_kernel_tracer();
2805 if (kernel_tracer_fd == 0) {
2806 ret = LTTCOMM_KERN_NA;
2807 goto error;
2808 }
2809 }
2810
2811 /* Need a session for kernel command */
2812 if (need_tracing_session) {
2813 if (cmd_ctx->session->kernel_session == NULL) {
2814 ret = create_kernel_session(cmd_ctx->session);
2815 if (ret < 0) {
2816 ret = LTTCOMM_KERN_SESS_FAIL;
2817 goto error;
2818 }
2819 }
2820
2821 /* Start the kernel consumer daemon */
2822 pthread_mutex_lock(&kconsumer_data.pid_mutex);
2823 if (kconsumer_data.pid == 0 &&
2824 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
2825 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2826 ret = start_consumerd(&kconsumer_data);
2827 if (ret < 0) {
2828 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2829 goto error;
2830 }
2831 }
2832 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2833 }
2834 break;
2835 case LTTNG_DOMAIN_UST:
2836 {
2837 if (need_tracing_session) {
2838 if (cmd_ctx->session->ust_session == NULL) {
2839 ret = create_ust_session(cmd_ctx->session,
2840 &cmd_ctx->lsm->domain);
2841 if (ret != LTTCOMM_OK) {
2842 goto error;
2843 }
2844 }
2845 /* Start the kernel consumer daemon */
2846 pthread_mutex_lock(&ustconsumer_data.pid_mutex);
2847 if (ustconsumer_data.pid == 0 &&
2848 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
2849 pthread_mutex_unlock(&ustconsumer_data.pid_mutex);
2850 ret = start_consumerd(&ustconsumer_data);
2851 if (ret < 0) {
2852 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2853 goto error;
2854 }
2855
2856 cmd_ctx->session->ust_session->consumer_fd =
2857 ustconsumer_data.cmd_sock;
2858 }
2859 pthread_mutex_unlock(&ustconsumer_data.pid_mutex);
2860 }
2861 break;
2862 }
2863 default:
2864 break;
2865 }
2866
2867 /* Process by command type */
2868 switch (cmd_ctx->lsm->cmd_type) {
2869 case LTTNG_ADD_CONTEXT:
2870 {
2871 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2872 cmd_ctx->lsm->u.context.channel_name,
2873 cmd_ctx->lsm->u.context.event_name,
2874 &cmd_ctx->lsm->u.context.ctx);
2875 break;
2876 }
2877 case LTTNG_DISABLE_CHANNEL:
2878 {
2879 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2880 cmd_ctx->lsm->u.disable.channel_name);
2881 break;
2882 }
2883 case LTTNG_DISABLE_EVENT:
2884 {
2885 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2886 cmd_ctx->lsm->u.disable.channel_name,
2887 cmd_ctx->lsm->u.disable.name);
2888 ret = LTTCOMM_OK;
2889 break;
2890 }
2891 case LTTNG_DISABLE_ALL_EVENT:
2892 {
2893 DBG("Disabling all events");
2894
2895 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2896 cmd_ctx->lsm->u.disable.channel_name);
2897 break;
2898 }
2899 case LTTNG_ENABLE_CHANNEL:
2900 {
2901 ret = cmd_enable_channel(cmd_ctx->session, &cmd_ctx->lsm->domain,
2902 &cmd_ctx->lsm->u.channel.chan);
2903 break;
2904 }
2905 case LTTNG_ENABLE_EVENT:
2906 {
2907 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2908 cmd_ctx->lsm->u.enable.channel_name,
2909 &cmd_ctx->lsm->u.enable.event);
2910 break;
2911 }
2912 case LTTNG_ENABLE_ALL_EVENT:
2913 {
2914 DBG("Enabling all events");
2915
2916 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2917 cmd_ctx->lsm->u.enable.channel_name,
2918 cmd_ctx->lsm->u.enable.event.type);
2919 break;
2920 }
2921 case LTTNG_LIST_TRACEPOINTS:
2922 {
2923 struct lttng_event *events;
2924 ssize_t nb_events;
2925
2926 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
2927 if (nb_events < 0) {
2928 ret = -nb_events;
2929 goto error;
2930 }
2931
2932 /*
2933 * Setup lttng message with payload size set to the event list size in
2934 * bytes and then copy list into the llm payload.
2935 */
2936 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
2937 if (ret < 0) {
2938 free(events);
2939 goto setup_error;
2940 }
2941
2942 /* Copy event list into message payload */
2943 memcpy(cmd_ctx->llm->payload, events,
2944 sizeof(struct lttng_event) * nb_events);
2945
2946 free(events);
2947
2948 ret = LTTCOMM_OK;
2949 break;
2950 }
2951 case LTTNG_START_TRACE:
2952 {
2953 ret = cmd_start_trace(cmd_ctx->session);
2954 break;
2955 }
2956 case LTTNG_STOP_TRACE:
2957 {
2958 ret = cmd_stop_trace(cmd_ctx->session);
2959 break;
2960 }
2961 case LTTNG_CREATE_SESSION:
2962 {
2963 ret = cmd_create_session(cmd_ctx->lsm->session.name,
2964 cmd_ctx->lsm->session.path);
2965 break;
2966 }
2967 case LTTNG_DESTROY_SESSION:
2968 {
2969 ret = cmd_destroy_session(cmd_ctx->session,
2970 cmd_ctx->lsm->session.name);
2971 break;
2972 }
2973 case LTTNG_LIST_DOMAINS:
2974 {
2975 ssize_t nb_dom;
2976 struct lttng_domain *domains;
2977
2978 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
2979 if (nb_dom < 0) {
2980 ret = -nb_dom;
2981 goto error;
2982 }
2983
2984 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
2985 if (ret < 0) {
2986 goto setup_error;
2987 }
2988
2989 /* Copy event list into message payload */
2990 memcpy(cmd_ctx->llm->payload, domains,
2991 nb_dom * sizeof(struct lttng_domain));
2992
2993 free(domains);
2994
2995 ret = LTTCOMM_OK;
2996 break;
2997 }
2998 case LTTNG_LIST_CHANNELS:
2999 {
3000 size_t nb_chan;
3001 struct lttng_channel *channels;
3002
3003 nb_chan = cmd_list_channels(cmd_ctx->session, &channels);
3004 if (nb_chan < 0) {
3005 ret = -nb_chan;
3006 goto error;
3007 }
3008
3009 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3010 if (ret < 0) {
3011 goto setup_error;
3012 }
3013
3014 /* Copy event list into message payload */
3015 memcpy(cmd_ctx->llm->payload, channels,
3016 nb_chan * sizeof(struct lttng_channel));
3017
3018 free(channels);
3019
3020 ret = LTTCOMM_OK;
3021 break;
3022 }
3023 case LTTNG_LIST_EVENTS:
3024 {
3025 size_t nb_event;
3026 struct lttng_event *events = NULL;
3027
3028 nb_event = cmd_list_events(cmd_ctx->session,
3029 cmd_ctx->lsm->u.list.channel_name, &events);
3030 if (nb_event < 0) {
3031 ret = -nb_event;
3032 goto error;
3033 }
3034
3035 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3036 if (ret < 0) {
3037 goto setup_error;
3038 }
3039
3040 /* Copy event list into message payload */
3041 memcpy(cmd_ctx->llm->payload, events,
3042 nb_event * sizeof(struct lttng_event));
3043
3044 free(events);
3045
3046 ret = LTTCOMM_OK;
3047 break;
3048 }
3049 case LTTNG_LIST_SESSIONS:
3050 {
3051 session_lock_list();
3052
3053 if (session_list_ptr->count == 0) {
3054 ret = LTTCOMM_NO_SESSION;
3055 session_unlock_list();
3056 goto error;
3057 }
3058
3059 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) *
3060 session_list_ptr->count);
3061 if (ret < 0) {
3062 session_unlock_list();
3063 goto setup_error;
3064 }
3065
3066 /* Filled the session array */
3067 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
3068
3069 session_unlock_list();
3070
3071 ret = LTTCOMM_OK;
3072 break;
3073 }
3074 case LTTNG_CALIBRATE:
3075 {
3076 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3077 &cmd_ctx->lsm->u.calibrate);
3078 break;
3079 }
3080 case LTTNG_REGISTER_CONSUMER:
3081 {
3082 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3083 cmd_ctx->lsm->u.reg.path);
3084 break;
3085 }
3086 default:
3087 ret = LTTCOMM_UND;
3088 break;
3089 }
3090
3091 error:
3092 if (cmd_ctx->llm == NULL) {
3093 DBG("Missing llm structure. Allocating one.");
3094 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3095 goto setup_error;
3096 }
3097 }
3098 /* Set return code */
3099 cmd_ctx->llm->ret_code = ret;
3100 setup_error:
3101 if (cmd_ctx->session) {
3102 session_unlock(cmd_ctx->session);
3103 }
3104 init_setup_error:
3105 return ret;
3106 }
3107
3108 /*
3109 * This thread manage all clients request using the unix client socket for
3110 * communication.
3111 */
3112 static void *thread_manage_clients(void *data)
3113 {
3114 int sock = 0, ret, i, pollfd;
3115 uint32_t revents, nb_fd;
3116 struct command_ctx *cmd_ctx = NULL;
3117 struct lttng_poll_event events;
3118
3119 DBG("[thread] Manage client started");
3120
3121 rcu_register_thread();
3122
3123 ret = lttcomm_listen_unix_sock(client_sock);
3124 if (ret < 0) {
3125 goto error;
3126 }
3127
3128 /*
3129 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3130 * more will be added to this poll set.
3131 */
3132 ret = create_thread_poll_set(&events, 2);
3133 if (ret < 0) {
3134 goto error;
3135 }
3136
3137 /* Add the application registration socket */
3138 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3139 if (ret < 0) {
3140 goto error;
3141 }
3142
3143 /*
3144 * Notify parent pid that we are ready to accept command for client side.
3145 */
3146 if (opt_sig_parent) {
3147 kill(ppid, SIGCHLD);
3148 }
3149
3150 while (1) {
3151 DBG("Accepting client command ...");
3152
3153 nb_fd = LTTNG_POLL_GETNB(&events);
3154
3155 /* Inifinite blocking call, waiting for transmission */
3156 ret = lttng_poll_wait(&events, -1);
3157 if (ret < 0) {
3158 goto error;
3159 }
3160
3161 for (i = 0; i < nb_fd; i++) {
3162 /* Fetch once the poll data */
3163 revents = LTTNG_POLL_GETEV(&events, i);
3164 pollfd = LTTNG_POLL_GETFD(&events, i);
3165
3166 /* Thread quit pipe has been closed. Killing thread. */
3167 ret = check_thread_quit_pipe(pollfd, revents);
3168 if (ret) {
3169 goto error;
3170 }
3171
3172 /* Event on the registration socket */
3173 if (pollfd == client_sock) {
3174 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3175 ERR("Client socket poll error");
3176 goto error;
3177 }
3178 }
3179 }
3180
3181 DBG("Wait for client response");
3182
3183 sock = lttcomm_accept_unix_sock(client_sock);
3184 if (sock < 0) {
3185 goto error;
3186 }
3187
3188 /* Allocate context command to process the client request */
3189 cmd_ctx = malloc(sizeof(struct command_ctx));
3190 if (cmd_ctx == NULL) {
3191 perror("malloc cmd_ctx");
3192 goto error;
3193 }
3194
3195 /* Allocate data buffer for reception */
3196 cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
3197 if (cmd_ctx->lsm == NULL) {
3198 perror("malloc cmd_ctx->lsm");
3199 goto error;
3200 }
3201
3202 cmd_ctx->llm = NULL;
3203 cmd_ctx->session = NULL;
3204
3205 /*
3206 * Data is received from the lttng client. The struct
3207 * lttcomm_session_msg (lsm) contains the command and data request of
3208 * the client.
3209 */
3210 DBG("Receiving data from client ...");
3211 ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm,
3212 sizeof(struct lttcomm_session_msg));
3213 if (ret <= 0) {
3214 DBG("Nothing recv() from client... continuing");
3215 close(sock);
3216 free(cmd_ctx);
3217 continue;
3218 }
3219
3220 // TODO: Validate cmd_ctx including sanity check for
3221 // security purpose.
3222
3223 rcu_thread_online();
3224 /*
3225 * This function dispatch the work to the kernel or userspace tracer
3226 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3227 * informations for the client. The command context struct contains
3228 * everything this function may needs.
3229 */
3230 ret = process_client_msg(cmd_ctx);
3231 rcu_thread_offline();
3232 if (ret < 0) {
3233 /*
3234 * TODO: Inform client somehow of the fatal error. At
3235 * this point, ret < 0 means that a malloc failed
3236 * (ENOMEM). Error detected but still accept command.
3237 */
3238 clean_command_ctx(&cmd_ctx);
3239 continue;
3240 }
3241
3242 DBG("Sending response (size: %d, retcode: %s)",
3243 cmd_ctx->lttng_msg_size,
3244 lttng_strerror(-cmd_ctx->llm->ret_code));
3245 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3246 if (ret < 0) {
3247 ERR("Failed to send data back to client");
3248 }
3249
3250 clean_command_ctx(&cmd_ctx);
3251
3252 /* End of transmission */
3253 close(sock);
3254 }
3255
3256 error:
3257 DBG("Client thread dying");
3258 unlink(client_unix_sock_path);
3259 close(client_sock);
3260 close(sock);
3261
3262 lttng_poll_clean(&events);
3263 clean_command_ctx(&cmd_ctx);
3264
3265 rcu_unregister_thread();
3266 return NULL;
3267 }
3268
3269
3270 /*
3271 * usage function on stderr
3272 */
3273 static void usage(void)
3274 {
3275 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3276 fprintf(stderr, " -h, --help Display this usage.\n");
3277 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3278 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3279 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3280 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3281 fprintf(stderr, " --ustconsumerd-err-sock PATH Specify path for the UST consumer error socket\n");
3282 fprintf(stderr, " --ustconsumerd-cmd-sock PATH Specify path for the UST consumer command socket\n");
3283 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3284 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3285 fprintf(stderr, " -V, --version Show version number.\n");
3286 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3287 fprintf(stderr, " -q, --quiet No output at all.\n");
3288 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3289 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3290 }
3291
3292 /*
3293 * daemon argument parsing
3294 */
3295 static int parse_args(int argc, char **argv)
3296 {
3297 int c;
3298
3299 static struct option long_options[] = {
3300 { "client-sock", 1, 0, 'c' },
3301 { "apps-sock", 1, 0, 'a' },
3302 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3303 { "kconsumerd-err-sock", 1, 0, 'E' },
3304 { "ustconsumerd-cmd-sock", 1, 0, 'D' },
3305 { "ustconsumerd-err-sock", 1, 0, 'F' },
3306 { "daemonize", 0, 0, 'd' },
3307 { "sig-parent", 0, 0, 'S' },
3308 { "help", 0, 0, 'h' },
3309 { "group", 1, 0, 'g' },
3310 { "version", 0, 0, 'V' },
3311 { "quiet", 0, 0, 'q' },
3312 { "verbose", 0, 0, 'v' },
3313 { "verbose-consumer", 0, 0, 'Z' },
3314 { NULL, 0, 0, 0 }
3315 };
3316
3317 while (1) {
3318 int option_index = 0;
3319 c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:C:E:D:F:Z",
3320 long_options, &option_index);
3321 if (c == -1) {
3322 break;
3323 }
3324
3325 switch (c) {
3326 case 0:
3327 fprintf(stderr, "option %s", long_options[option_index].name);
3328 if (optarg) {
3329 fprintf(stderr, " with arg %s\n", optarg);
3330 }
3331 break;
3332 case 'c':
3333 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3334 break;
3335 case 'a':
3336 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3337 break;
3338 case 'd':
3339 opt_daemon = 1;
3340 break;
3341 case 'g':
3342 opt_tracing_group = strdup(optarg);
3343 break;
3344 case 'h':
3345 usage();
3346 exit(EXIT_FAILURE);
3347 case 'V':
3348 fprintf(stdout, "%s\n", VERSION);
3349 exit(EXIT_SUCCESS);
3350 case 'S':
3351 opt_sig_parent = 1;
3352 break;
3353 case 'E':
3354 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3355 break;
3356 case 'C':
3357 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3358 break;
3359 case 'F':
3360 snprintf(ustconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3361 break;
3362 case 'D':
3363 snprintf(ustconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3364 break;
3365 case 'q':
3366 opt_quiet = 1;
3367 break;
3368 case 'v':
3369 /* Verbose level can increase using multiple -v */
3370 opt_verbose += 1;
3371 break;
3372 case 'Z':
3373 opt_verbose_consumer += 1;
3374 break;
3375 default:
3376 /* Unknown option or other error.
3377 * Error is printed by getopt, just return */
3378 return -1;
3379 }
3380 }
3381
3382 return 0;
3383 }
3384
3385 /*
3386 * Creates the two needed socket by the daemon.
3387 * apps_sock - The communication socket for all UST apps.
3388 * client_sock - The communication of the cli tool (lttng).
3389 */
3390 static int init_daemon_socket(void)
3391 {
3392 int ret = 0;
3393 mode_t old_umask;
3394
3395 old_umask = umask(0);
3396
3397 /* Create client tool unix socket */
3398 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3399 if (client_sock < 0) {
3400 ERR("Create unix sock failed: %s", client_unix_sock_path);
3401 ret = -1;
3402 goto end;
3403 }
3404
3405 /* File permission MUST be 660 */
3406 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3407 if (ret < 0) {
3408 ERR("Set file permissions failed: %s", client_unix_sock_path);
3409 perror("chmod");
3410 goto end;
3411 }
3412
3413 /* Create the application unix socket */
3414 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3415 if (apps_sock < 0) {
3416 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3417 ret = -1;
3418 goto end;
3419 }
3420
3421 /* File permission MUST be 666 */
3422 ret = chmod(apps_unix_sock_path,
3423 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3424 if (ret < 0) {
3425 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3426 perror("chmod");
3427 goto end;
3428 }
3429
3430 end:
3431 umask(old_umask);
3432 return ret;
3433 }
3434
3435 /*
3436 * Check if the global socket is available, and if a daemon is answering at the
3437 * other side. If yes, error is returned.
3438 */
3439 static int check_existing_daemon(void)
3440 {
3441 if (access(client_unix_sock_path, F_OK) < 0 &&
3442 access(apps_unix_sock_path, F_OK) < 0) {
3443 return 0;
3444 }
3445
3446 /* Is there anybody out there ? */
3447 if (lttng_session_daemon_alive()) {
3448 return -EEXIST;
3449 } else {
3450 return 0;
3451 }
3452 }
3453
3454 /*
3455 * Set the tracing group gid onto the client socket.
3456 *
3457 * Race window between mkdir and chown is OK because we are going from more
3458 * permissive (root.root) to les permissive (root.tracing).
3459 */
3460 static int set_permissions(void)
3461 {
3462 int ret;
3463 gid_t gid;
3464
3465 gid = allowed_group();
3466 if (gid < 0) {
3467 if (is_root) {
3468 WARN("No tracing group detected");
3469 ret = 0;
3470 } else {
3471 ERR("Missing tracing group. Aborting execution.");
3472 ret = -1;
3473 }
3474 goto end;
3475 }
3476
3477 /* Set lttng run dir */
3478 ret = chown(LTTNG_RUNDIR, 0, gid);
3479 if (ret < 0) {
3480 ERR("Unable to set group on " LTTNG_RUNDIR);
3481 perror("chown");
3482 }
3483
3484 /* lttng client socket path */
3485 ret = chown(client_unix_sock_path, 0, gid);
3486 if (ret < 0) {
3487 ERR("Unable to set group on %s", client_unix_sock_path);
3488 perror("chown");
3489 }
3490
3491 /* kconsumer error socket path */
3492 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
3493 if (ret < 0) {
3494 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
3495 perror("chown");
3496 }
3497
3498 /* ustconsumer error socket path */
3499 ret = chown(ustconsumer_data.err_unix_sock_path, 0, gid);
3500 if (ret < 0) {
3501 ERR("Unable to set group on %s", ustconsumer_data.err_unix_sock_path);
3502 perror("chown");
3503 }
3504
3505 DBG("All permissions are set");
3506
3507 end:
3508 return ret;
3509 }
3510
3511 /*
3512 * Create the pipe used to wake up the kernel thread.
3513 */
3514 static int create_kernel_poll_pipe(void)
3515 {
3516 return pipe2(kernel_poll_pipe, O_CLOEXEC);
3517 }
3518
3519 /*
3520 * Create the application command pipe to wake thread_manage_apps.
3521 */
3522 static int create_apps_cmd_pipe(void)
3523 {
3524 return pipe2(apps_cmd_pipe, O_CLOEXEC);
3525 }
3526
3527 /*
3528 * Create the lttng run directory needed for all global sockets and pipe.
3529 */
3530 static int create_lttng_rundir(void)
3531 {
3532 int ret;
3533
3534 ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG );
3535 if (ret < 0) {
3536 if (errno != EEXIST) {
3537 ERR("Unable to create " LTTNG_RUNDIR);
3538 goto error;
3539 } else {
3540 ret = 0;
3541 }
3542 }
3543
3544 error:
3545 return ret;
3546 }
3547
3548 /*
3549 * Setup sockets and directory needed by the kconsumerd communication with the
3550 * session daemon.
3551 */
3552 static int set_consumer_sockets(struct consumer_data *consumer_data)
3553 {
3554 int ret;
3555 const char *path = consumer_data->type == LTTNG_CONSUMER_KERNEL ?
3556 KCONSUMERD_PATH : USTCONSUMERD_PATH;
3557
3558 if (strlen(consumer_data->err_unix_sock_path) == 0) {
3559 snprintf(consumer_data->err_unix_sock_path, PATH_MAX,
3560 consumer_data->type == LTTNG_CONSUMER_KERNEL ?
3561 KCONSUMERD_ERR_SOCK_PATH :
3562 USTCONSUMERD_ERR_SOCK_PATH);
3563 }
3564
3565 if (strlen(consumer_data->cmd_unix_sock_path) == 0) {
3566 snprintf(consumer_data->cmd_unix_sock_path, PATH_MAX,
3567 consumer_data->type == LTTNG_CONSUMER_KERNEL ?
3568 KCONSUMERD_CMD_SOCK_PATH :
3569 USTCONSUMERD_CMD_SOCK_PATH);
3570 }
3571
3572 ret = mkdir(path, S_IRWXU | S_IRWXG);
3573 if (ret < 0) {
3574 if (errno != EEXIST) {
3575 ERR("Failed to create %s", path);
3576 goto error;
3577 }
3578 ret = 0;
3579 }
3580
3581 /* Create the kconsumerd error unix socket */
3582 consumer_data->err_sock =
3583 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
3584 if (consumer_data->err_sock < 0) {
3585 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
3586 ret = -1;
3587 goto error;
3588 }
3589
3590 /* File permission MUST be 660 */
3591 ret = chmod(consumer_data->err_unix_sock_path,
3592 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3593 if (ret < 0) {
3594 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
3595 perror("chmod");
3596 goto error;
3597 }
3598
3599 error:
3600 return ret;
3601 }
3602
3603 /*
3604 * Signal handler for the daemon
3605 *
3606 * Simply stop all worker threads, leaving main() return gracefully after
3607 * joining all threads and calling cleanup().
3608 */
3609 static void sighandler(int sig)
3610 {
3611 switch (sig) {
3612 case SIGPIPE:
3613 DBG("SIGPIPE catched");
3614 return;
3615 case SIGINT:
3616 DBG("SIGINT catched");
3617 stop_threads();
3618 break;
3619 case SIGTERM:
3620 DBG("SIGTERM catched");
3621 stop_threads();
3622 break;
3623 default:
3624 break;
3625 }
3626 }
3627
3628 /*
3629 * Setup signal handler for :
3630 * SIGINT, SIGTERM, SIGPIPE
3631 */
3632 static int set_signal_handler(void)
3633 {
3634 int ret = 0;
3635 struct sigaction sa;
3636 sigset_t sigset;
3637
3638 if ((ret = sigemptyset(&sigset)) < 0) {
3639 perror("sigemptyset");
3640 return ret;
3641 }
3642
3643 sa.sa_handler = sighandler;
3644 sa.sa_mask = sigset;
3645 sa.sa_flags = 0;
3646 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
3647 perror("sigaction");
3648 return ret;
3649 }
3650
3651 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
3652 perror("sigaction");
3653 return ret;
3654 }
3655
3656 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
3657 perror("sigaction");
3658 return ret;
3659 }
3660
3661 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3662
3663 return ret;
3664 }
3665
3666 /*
3667 * Set open files limit to unlimited. This daemon can open a large number of
3668 * file descriptors in order to consumer multiple kernel traces.
3669 */
3670 static void set_ulimit(void)
3671 {
3672 int ret;
3673 struct rlimit lim;
3674
3675 /* The kernel does not allowed an infinite limit for open files */
3676 lim.rlim_cur = 65535;
3677 lim.rlim_max = 65535;
3678
3679 ret = setrlimit(RLIMIT_NOFILE, &lim);
3680 if (ret < 0) {
3681 perror("failed to set open files limit");
3682 }
3683 }
3684
3685 /*
3686 * main
3687 */
3688 int main(int argc, char **argv)
3689 {
3690 int ret = 0;
3691 void *status;
3692 const char *home_path;
3693
3694 rcu_register_thread();
3695
3696 /* Create thread quit pipe */
3697 if ((ret = init_thread_quit_pipe()) < 0) {
3698 goto error;
3699 }
3700
3701 /* Parse arguments */
3702 progname = argv[0];
3703 if ((ret = parse_args(argc, argv) < 0)) {
3704 goto error;
3705 }
3706
3707 /* Daemonize */
3708 if (opt_daemon) {
3709 ret = daemon(0, 0);
3710 if (ret < 0) {
3711 perror("daemon");
3712 goto error;
3713 }
3714 }
3715
3716 /* Check if daemon is UID = 0 */
3717 is_root = !getuid();
3718
3719 if (is_root) {
3720 ret = create_lttng_rundir();
3721 if (ret < 0) {
3722 goto error;
3723 }
3724
3725 if (strlen(apps_unix_sock_path) == 0) {
3726 snprintf(apps_unix_sock_path, PATH_MAX,
3727 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
3728 }
3729
3730 if (strlen(client_unix_sock_path) == 0) {
3731 snprintf(client_unix_sock_path, PATH_MAX,
3732 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
3733 }
3734
3735 /* Set global SHM for ust */
3736 if (strlen(wait_shm_path) == 0) {
3737 snprintf(wait_shm_path, PATH_MAX,
3738 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
3739 }
3740 } else {
3741 home_path = get_home_dir();
3742 if (home_path == NULL) {
3743 /* TODO: Add --socket PATH option */
3744 ERR("Can't get HOME directory for sockets creation.");
3745 ret = -EPERM;
3746 goto error;
3747 }
3748
3749 if (strlen(apps_unix_sock_path) == 0) {
3750 snprintf(apps_unix_sock_path, PATH_MAX,
3751 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
3752 }
3753
3754 /* Set the cli tool unix socket path */
3755 if (strlen(client_unix_sock_path) == 0) {
3756 snprintf(client_unix_sock_path, PATH_MAX,
3757 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
3758 }
3759
3760 /* Set global SHM for ust */
3761 if (strlen(wait_shm_path) == 0) {
3762 snprintf(wait_shm_path, PATH_MAX,
3763 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
3764 }
3765 }
3766
3767 DBG("Client socket path %s", client_unix_sock_path);
3768 DBG("Application socket path %s", apps_unix_sock_path);
3769
3770 /*
3771 * See if daemon already exist.
3772 */
3773 if ((ret = check_existing_daemon()) < 0) {
3774 ERR("Already running daemon.\n");
3775 /*
3776 * We do not goto exit because we must not cleanup()
3777 * because a daemon is already running.
3778 */
3779 goto error;
3780 }
3781
3782 /* After this point, we can safely call cleanup() with "goto exit" */
3783
3784 /*
3785 * These actions must be executed as root. We do that *after* setting up
3786 * the sockets path because we MUST make the check for another daemon using
3787 * those paths *before* trying to set the kernel consumer sockets and init
3788 * kernel tracer.
3789 */
3790 if (is_root) {
3791 ret = set_consumer_sockets(&kconsumer_data);
3792 if (ret < 0) {
3793 goto exit;
3794 }
3795
3796 ret = set_consumer_sockets(&ustconsumer_data);
3797 if (ret < 0) {
3798 goto exit;
3799 }
3800 /* Setup kernel tracer */
3801 init_kernel_tracer();
3802
3803 /* Set ulimit for open files */
3804 set_ulimit();
3805 }
3806
3807 if ((ret = set_signal_handler()) < 0) {
3808 goto exit;
3809 }
3810
3811 /* Setup the needed unix socket */
3812 if ((ret = init_daemon_socket()) < 0) {
3813 goto exit;
3814 }
3815
3816 /* Set credentials to socket */
3817 if (is_root && ((ret = set_permissions()) < 0)) {
3818 goto exit;
3819 }
3820
3821 /* Get parent pid if -S, --sig-parent is specified. */
3822 if (opt_sig_parent) {
3823 ppid = getppid();
3824 }
3825
3826 /* Setup the kernel pipe for waking up the kernel thread */
3827 if ((ret = create_kernel_poll_pipe()) < 0) {
3828 goto exit;
3829 }
3830
3831 /* Setup the thread apps communication pipe. */
3832 if ((ret = create_apps_cmd_pipe()) < 0) {
3833 goto exit;
3834 }
3835
3836 /* Init UST command queue. */
3837 cds_wfq_init(&ust_cmd_queue.queue);
3838
3839 /* Init UST app hash table */
3840 ust_app_ht_alloc();
3841
3842 /*
3843 * Get session list pointer. This pointer MUST NOT be free(). This list is
3844 * statically declared in session.c
3845 */
3846 session_list_ptr = session_get_list();
3847
3848 /* Set up max poll set size */
3849 lttng_poll_set_max_size();
3850
3851 /* Create thread to manage the client socket */
3852 ret = pthread_create(&client_thread, NULL,
3853 thread_manage_clients, (void *) NULL);
3854 if (ret != 0) {
3855 perror("pthread_create clients");
3856 goto exit_client;
3857 }
3858
3859 /* Create thread to dispatch registration */
3860 ret = pthread_create(&dispatch_thread, NULL,
3861 thread_dispatch_ust_registration, (void *) NULL);
3862 if (ret != 0) {
3863 perror("pthread_create dispatch");
3864 goto exit_dispatch;
3865 }
3866
3867 /* Create thread to manage application registration. */
3868 ret = pthread_create(&reg_apps_thread, NULL,
3869 thread_registration_apps, (void *) NULL);
3870 if (ret != 0) {
3871 perror("pthread_create registration");
3872 goto exit_reg_apps;
3873 }
3874
3875 /* Create thread to manage application socket */
3876 ret = pthread_create(&apps_thread, NULL,
3877 thread_manage_apps, (void *) NULL);
3878 if (ret != 0) {
3879 perror("pthread_create apps");
3880 goto exit_apps;
3881 }
3882
3883 /* Create kernel thread to manage kernel event */
3884 ret = pthread_create(&kernel_thread, NULL,
3885 thread_manage_kernel, (void *) NULL);
3886 if (ret != 0) {
3887 perror("pthread_create kernel");
3888 goto exit_kernel;
3889 }
3890
3891 ret = pthread_join(kernel_thread, &status);
3892 if (ret != 0) {
3893 perror("pthread_join");
3894 goto error; /* join error, exit without cleanup */
3895 }
3896
3897 exit_kernel:
3898 ret = pthread_join(apps_thread, &status);
3899 if (ret != 0) {
3900 perror("pthread_join");
3901 goto error; /* join error, exit without cleanup */
3902 }
3903
3904 exit_apps:
3905 ret = pthread_join(reg_apps_thread, &status);
3906 if (ret != 0) {
3907 perror("pthread_join");
3908 goto error; /* join error, exit without cleanup */
3909 }
3910
3911 exit_reg_apps:
3912 ret = pthread_join(dispatch_thread, &status);
3913 if (ret != 0) {
3914 perror("pthread_join");
3915 goto error; /* join error, exit without cleanup */
3916 }
3917
3918 exit_dispatch:
3919 ret = pthread_join(client_thread, &status);
3920 if (ret != 0) {
3921 perror("pthread_join");
3922 goto error; /* join error, exit without cleanup */
3923 }
3924
3925 ret = join_consumer_thread(&kconsumer_data);
3926 if (ret != 0) {
3927 perror("join_consumer");
3928 goto error; /* join error, exit without cleanup */
3929 }
3930
3931 exit_client:
3932 exit:
3933 /*
3934 * cleanup() is called when no other thread is running.
3935 */
3936 rcu_thread_online();
3937 cleanup();
3938 rcu_thread_offline();
3939 rcu_unregister_thread();
3940 if (!ret)
3941 exit(EXIT_SUCCESS);
3942 error:
3943 exit(EXIT_FAILURE);
3944 }
LTTng 2.0 tools and control repository
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