Fix debug message channel vs session name mixup
[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(int domain, 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 switch (domain) {
1807 case LTTNG_DOMAIN_KERNEL:
1808 /* Kernel channels */
1809 if (session->kernel_session != NULL) {
1810 cds_list_for_each_entry(kchan,
1811 &session->kernel_session->channel_list.head, list) {
1812 /* Copy lttng_channel struct to array */
1813 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
1814 channels[i].enabled = kchan->enabled;
1815 i++;
1816 }
1817 }
1818 break;
1819 case LTTNG_DOMAIN_UST:
1820 {
1821 struct cds_lfht_iter iter;
1822 struct ltt_ust_channel *uchan;
1823
1824 cds_lfht_for_each_entry(session->ust_session->domain_global.channels,
1825 &iter, uchan, node) {
1826 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
1827 channels[i].attr.overwrite = uchan->attr.overwrite;
1828 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
1829 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
1830 channels[i].attr.switch_timer_interval =
1831 uchan->attr.switch_timer_interval;
1832 channels[i].attr.read_timer_interval =
1833 uchan->attr.read_timer_interval;
1834 channels[i].attr.output = uchan->attr.output;
1835 }
1836 break;
1837 }
1838 default:
1839 break;
1840 }
1841 }
1842
1843 /*
1844 * Create a list of ust global domain events.
1845 */
1846 static int list_lttng_ust_global_events(char *channel_name,
1847 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
1848 {
1849 int i = 0, ret = 0;
1850 unsigned int nb_event = 0;
1851 struct cds_lfht_iter iter;
1852 struct ltt_ust_channel *uchan;
1853 struct ltt_ust_event *uevent;
1854 struct lttng_event *tmp;
1855
1856 DBG("Listing UST global events for channel %s", channel_name);
1857
1858 rcu_read_lock();
1859
1860 /* Count events in all channels */
1861 cds_lfht_for_each_entry(ust_global->channels, &iter, uchan, node) {
1862 nb_event += hashtable_get_count(uchan->events);
1863 }
1864
1865 if (nb_event == 0) {
1866 ret = nb_event;
1867 goto error;
1868 }
1869
1870 DBG3("Listing UST global %d events", nb_event);
1871
1872 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
1873 if (tmp == NULL) {
1874 ret = -LTTCOMM_FATAL;
1875 goto error;
1876 }
1877
1878 cds_lfht_for_each_entry(ust_global->channels, &iter, uchan, node) {
1879 cds_lfht_for_each_entry(uchan->events, &iter, uevent, node) {
1880 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
1881 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
1882 switch (uevent->attr.instrumentation) {
1883 case LTTNG_UST_TRACEPOINT:
1884 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
1885 break;
1886 case LTTNG_UST_PROBE:
1887 tmp[i].type = LTTNG_EVENT_PROBE;
1888 break;
1889 case LTTNG_UST_FUNCTION:
1890 tmp[i].type = LTTNG_EVENT_FUNCTION;
1891 break;
1892 }
1893 i++;
1894 }
1895 }
1896
1897 ret = nb_event;
1898 *events = tmp;
1899
1900 error:
1901 rcu_read_unlock();
1902 return ret;
1903 }
1904
1905 /*
1906 * Fill lttng_event array of all kernel events in the channel.
1907 */
1908 static int list_lttng_kernel_events(char *channel_name,
1909 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
1910 {
1911 int i = 0, ret;
1912 unsigned int nb_event;
1913 struct ltt_kernel_event *event;
1914 struct ltt_kernel_channel *kchan;
1915
1916 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
1917 if (kchan == NULL) {
1918 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
1919 goto error;
1920 }
1921
1922 nb_event = kchan->event_count;
1923
1924 DBG("Listing events for channel %s", kchan->channel->name);
1925
1926 if (nb_event == 0) {
1927 ret = nb_event;
1928 goto error;
1929 }
1930
1931 *events = zmalloc(nb_event * sizeof(struct lttng_event));
1932 if (*events == NULL) {
1933 ret = LTTCOMM_FATAL;
1934 goto error;
1935 }
1936
1937 /* Kernel channels */
1938 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
1939 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
1940 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
1941 (*events)[i].enabled = event->enabled;
1942 switch (event->event->instrumentation) {
1943 case LTTNG_KERNEL_TRACEPOINT:
1944 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
1945 break;
1946 case LTTNG_KERNEL_KPROBE:
1947 case LTTNG_KERNEL_KRETPROBE:
1948 (*events)[i].type = LTTNG_EVENT_PROBE;
1949 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
1950 sizeof(struct lttng_kernel_kprobe));
1951 break;
1952 case LTTNG_KERNEL_FUNCTION:
1953 (*events)[i].type = LTTNG_EVENT_FUNCTION;
1954 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
1955 sizeof(struct lttng_kernel_function));
1956 break;
1957 case LTTNG_KERNEL_NOOP:
1958 (*events)[i].type = LTTNG_EVENT_NOOP;
1959 break;
1960 case LTTNG_KERNEL_SYSCALL:
1961 (*events)[i].type = LTTNG_EVENT_SYSCALL;
1962 break;
1963 case LTTNG_KERNEL_ALL:
1964 assert(0);
1965 break;
1966 }
1967 i++;
1968 }
1969
1970 return nb_event;
1971
1972 error:
1973 return ret;
1974 }
1975
1976 /*
1977 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1978 */
1979 static int cmd_disable_channel(struct ltt_session *session,
1980 int domain, char *channel_name)
1981 {
1982 int ret;
1983
1984 switch (domain) {
1985 case LTTNG_DOMAIN_KERNEL:
1986 ret = channel_kernel_disable(session->kernel_session,
1987 channel_name);
1988 if (ret != LTTCOMM_OK) {
1989 goto error;
1990 }
1991
1992 kernel_wait_quiescent(kernel_tracer_fd);
1993 break;
1994 case LTTNG_DOMAIN_UST_PID:
1995 break;
1996 default:
1997 ret = LTTCOMM_UNKNOWN_DOMAIN;
1998 goto error;
1999 }
2000
2001 ret = LTTCOMM_OK;
2002
2003 error:
2004 return ret;
2005 }
2006
2007 /*
2008 * Copy channel from attributes and set it in the application channel list.
2009 */
2010 /*
2011 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
2012 struct lttng_channel *attr, struct ust_app *app)
2013 {
2014 int ret;
2015 struct ltt_ust_channel *uchan, *new_chan;
2016
2017 uchan = trace_ust_get_channel_by_key(usess->channels, attr->name);
2018 if (uchan == NULL) {
2019 ret = LTTCOMM_FATAL;
2020 goto error;
2021 }
2022
2023 new_chan = trace_ust_create_channel(attr, usess->path);
2024 if (new_chan == NULL) {
2025 PERROR("malloc ltt_ust_channel");
2026 ret = LTTCOMM_FATAL;
2027 goto error;
2028 }
2029
2030 ret = channel_ust_copy(new_chan, uchan);
2031 if (ret < 0) {
2032 ret = LTTCOMM_FATAL;
2033 goto error;
2034 }
2035
2036 error:
2037 return ret;
2038 }
2039 */
2040
2041 /*
2042 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2043 */
2044 static int cmd_enable_channel(struct ltt_session *session,
2045 struct lttng_domain *domain, struct lttng_channel *attr)
2046 {
2047 int ret;
2048 struct ltt_ust_session *usess = session->ust_session;
2049
2050 DBG("Enabling channel %s for session %s", attr->name, session->name);
2051
2052 switch (domain->type) {
2053 case LTTNG_DOMAIN_KERNEL:
2054 {
2055 struct ltt_kernel_channel *kchan;
2056
2057 kchan = trace_kernel_get_channel_by_name(attr->name,
2058 session->kernel_session);
2059 if (kchan == NULL) {
2060 ret = channel_kernel_create(session->kernel_session,
2061 attr, kernel_poll_pipe[1]);
2062 } else {
2063 ret = channel_kernel_enable(session->kernel_session, kchan);
2064 }
2065
2066 if (ret != LTTCOMM_OK) {
2067 goto error;
2068 }
2069
2070 kernel_wait_quiescent(kernel_tracer_fd);
2071 break;
2072 }
2073 case LTTNG_DOMAIN_UST:
2074 {
2075 struct ltt_ust_channel *uchan;
2076
2077 DBG2("Enabling channel for LTTNG_DOMAIN_UST");
2078
2079 /* Get channel in global UST domain HT */
2080 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2081 attr->name);
2082 if (uchan == NULL) {
2083 uchan = trace_ust_create_channel(attr, usess->pathname);
2084 if (uchan == NULL) {
2085 ret = LTTCOMM_UST_CHAN_FAIL;
2086 goto error;
2087 }
2088 rcu_read_lock();
2089 hashtable_add_unique(usess->domain_global.channels, &uchan->node);
2090 rcu_read_unlock();
2091 DBG2("UST channel %s added to global domain HT", attr->name);
2092 } else {
2093 ret = LTTCOMM_UST_CHAN_EXIST;
2094 goto error;
2095 }
2096
2097 /* Add channel to all registered applications */
2098 ret = ust_app_add_channel_all(usess, uchan);
2099 if (ret != 0) {
2100 goto error;
2101 }
2102
2103 break;
2104 }
2105 case LTTNG_DOMAIN_UST_PID:
2106 {
2107 /*
2108 int sock;
2109 struct ltt_ust_channel *uchan;
2110 struct ltt_ust_session *usess;
2111 struct ust_app *app;
2112
2113 usess = trace_ust_get_session_by_pid(&session->ust_session_list,
2114 domain->attr.pid);
2115 if (usess == NULL) {
2116 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2117 goto error;
2118 }
2119
2120 app = ust_app_get_by_pid(domain->attr.pid);
2121 if (app == NULL) {
2122 ret = LTTCOMM_APP_NOT_FOUND;
2123 goto error;
2124 }
2125 sock = app->sock;
2126
2127 uchan = trace_ust_get_channel_by_name(attr->name, usess);
2128 if (uchan == NULL) {
2129 ret = channel_ust_create(usess, attr, sock);
2130 } else {
2131 ret = channel_ust_enable(usess, uchan, sock);
2132 }
2133
2134 if (ret != LTTCOMM_OK) {
2135 goto error;
2136 }
2137
2138 ret = copy_ust_channel_to_app(usess, attr, app);
2139 if (ret != LTTCOMM_OK) {
2140 goto error;
2141 }
2142
2143 DBG("UST channel %s created for app sock %d with pid %d",
2144 attr->name, app->sock, domain->attr.pid);
2145 */
2146 ret = LTTCOMM_NOT_IMPLEMENTED;
2147 goto error;
2148 }
2149 default:
2150 ret = LTTCOMM_UNKNOWN_DOMAIN;
2151 goto error;
2152 }
2153
2154 ret = LTTCOMM_OK;
2155
2156 error:
2157 return ret;
2158 }
2159
2160 /*
2161 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2162 */
2163 static int cmd_disable_event(struct ltt_session *session, int domain,
2164 char *channel_name, char *event_name)
2165 {
2166 int ret;
2167
2168 switch (domain) {
2169 case LTTNG_DOMAIN_KERNEL:
2170 {
2171 struct ltt_kernel_channel *kchan;
2172
2173 kchan = trace_kernel_get_channel_by_name(channel_name,
2174 session->kernel_session);
2175 if (kchan == NULL) {
2176 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2177 goto error;
2178 }
2179
2180 ret = event_kernel_disable_tracepoint(session->kernel_session, kchan, event_name);
2181 if (ret != LTTCOMM_OK) {
2182 goto error;
2183 }
2184
2185 kernel_wait_quiescent(kernel_tracer_fd);
2186 break;
2187 }
2188 case LTTNG_DOMAIN_UST:
2189 case LTTNG_DOMAIN_UST_EXEC_NAME:
2190 case LTTNG_DOMAIN_UST_PID:
2191 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2192 default:
2193 /* TODO: Other UST domains */
2194 ret = LTTCOMM_NOT_IMPLEMENTED;
2195 goto error;
2196 }
2197
2198 ret = LTTCOMM_OK;
2199
2200 error:
2201 return ret;
2202 }
2203
2204 /*
2205 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2206 */
2207 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2208 char *channel_name)
2209 {
2210 int ret;
2211 struct ltt_kernel_channel *kchan;
2212
2213 switch (domain) {
2214 case LTTNG_DOMAIN_KERNEL:
2215 kchan = trace_kernel_get_channel_by_name(channel_name,
2216 session->kernel_session);
2217 if (kchan == NULL) {
2218 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2219 goto error;
2220 }
2221
2222 ret = event_kernel_disable_all(session->kernel_session, kchan);
2223 if (ret != LTTCOMM_OK) {
2224 goto error;
2225 }
2226
2227 kernel_wait_quiescent(kernel_tracer_fd);
2228 break;
2229 default:
2230 /* TODO: Userspace tracing */
2231 ret = LTTCOMM_NOT_IMPLEMENTED;
2232 goto error;
2233 }
2234
2235 ret = LTTCOMM_OK;
2236
2237 error:
2238 return ret;
2239 }
2240
2241 /*
2242 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2243 */
2244 static int cmd_add_context(struct ltt_session *session, int domain,
2245 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2246 {
2247 int ret;
2248
2249 switch (domain) {
2250 case LTTNG_DOMAIN_KERNEL:
2251 /* Add kernel context to kernel tracer */
2252 ret = context_kernel_add(session->kernel_session, ctx,
2253 event_name, channel_name);
2254 if (ret != LTTCOMM_OK) {
2255 goto error;
2256 }
2257 break;
2258 case LTTNG_DOMAIN_UST:
2259 {
2260 /*
2261 struct ltt_ust_session *usess;
2262
2263 cds_list_for_each_entry(usess, &session->ust_session_list.head, list) {
2264 ret = context_ust_add(usess, ctx,
2265 event_name, channel_name, domain);
2266 if (ret != LTTCOMM_OK) {
2267 goto error;
2268 }
2269 }
2270 break;
2271 */
2272 }
2273 default:
2274 /* TODO: UST other domains */
2275 ret = LTTCOMM_NOT_IMPLEMENTED;
2276 goto error;
2277 }
2278
2279 ret = LTTCOMM_OK;
2280
2281 error:
2282 return ret;
2283 }
2284
2285 /*
2286 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2287 */
2288 static int cmd_enable_event(struct ltt_session *session, int domain,
2289 char *channel_name, struct lttng_event *event)
2290 {
2291 int ret;
2292 struct lttng_channel *attr;
2293 struct ltt_ust_session *usess = session->ust_session;
2294
2295 switch (domain) {
2296 case LTTNG_DOMAIN_KERNEL:
2297 {
2298 struct ltt_kernel_channel *kchan;
2299
2300 kchan = trace_kernel_get_channel_by_name(channel_name,
2301 session->kernel_session);
2302 if (kchan == NULL) {
2303 attr = channel_new_default_attr(domain);
2304 if (attr == NULL) {
2305 ret = LTTCOMM_FATAL;
2306 goto error;
2307 }
2308 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2309
2310 /* This call will notify the kernel thread */
2311 ret = channel_kernel_create(session->kernel_session,
2312 attr, kernel_poll_pipe[1]);
2313 if (ret != LTTCOMM_OK) {
2314 goto error;
2315 }
2316 }
2317
2318 /* Get the newly created kernel channel pointer */
2319 kchan = trace_kernel_get_channel_by_name(channel_name,
2320 session->kernel_session);
2321 if (kchan == NULL) {
2322 /* This sould not happen... */
2323 ret = LTTCOMM_FATAL;
2324 goto error;
2325 }
2326
2327 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2328 event);
2329 if (ret != LTTCOMM_OK) {
2330 goto error;
2331 }
2332
2333 kernel_wait_quiescent(kernel_tracer_fd);
2334 break;
2335 }
2336 case LTTNG_DOMAIN_UST:
2337 {
2338 struct ltt_ust_channel *uchan;
2339 struct ltt_ust_event *uevent;
2340
2341 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2342 channel_name);
2343 if (uchan == NULL) {
2344 /* TODO: Create default channel */
2345 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2346 goto error;
2347 }
2348
2349 uevent = trace_ust_find_event_by_name(uchan->events, event->name);
2350 if (uevent == NULL) {
2351 uevent = trace_ust_create_event(event);
2352 if (uevent == NULL) {
2353 ret = LTTCOMM_FATAL;
2354 goto error;
2355 }
2356 }
2357
2358 ret = ust_app_add_event_all(usess, uchan, uevent);
2359 if (ret < 0) {
2360 ret = LTTCOMM_UST_ENABLE_FAIL;
2361 goto error;
2362 }
2363
2364 rcu_read_lock();
2365 hashtable_add_unique(uchan->events, &uevent->node);
2366 rcu_read_unlock();
2367 break;
2368 }
2369 case LTTNG_DOMAIN_UST_EXEC_NAME:
2370 case LTTNG_DOMAIN_UST_PID:
2371 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2372 default:
2373 ret = LTTCOMM_NOT_IMPLEMENTED;
2374 goto error;
2375 }
2376
2377 ret = LTTCOMM_OK;
2378
2379 error:
2380 return ret;
2381 }
2382
2383 /*
2384 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2385 */
2386 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2387 char *channel_name, int event_type)
2388 {
2389 int ret;
2390 struct ltt_kernel_channel *kchan;
2391
2392 switch (domain) {
2393 case LTTNG_DOMAIN_KERNEL:
2394 kchan = trace_kernel_get_channel_by_name(channel_name,
2395 session->kernel_session);
2396 if (kchan == NULL) {
2397 /* This call will notify the kernel thread */
2398 ret = channel_kernel_create(session->kernel_session, NULL,
2399 kernel_poll_pipe[1]);
2400 if (ret != LTTCOMM_OK) {
2401 goto error;
2402 }
2403 }
2404
2405 /* Get the newly created kernel channel pointer */
2406 kchan = trace_kernel_get_channel_by_name(channel_name,
2407 session->kernel_session);
2408 if (kchan == NULL) {
2409 /* This sould not happen... */
2410 ret = LTTCOMM_FATAL;
2411 goto error;
2412 }
2413
2414 switch (event_type) {
2415 case LTTNG_KERNEL_SYSCALL:
2416 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2417 kchan, kernel_tracer_fd);
2418 break;
2419 case LTTNG_KERNEL_TRACEPOINT:
2420 /*
2421 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2422 * events already registered to the channel.
2423 */
2424 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2425 kchan, kernel_tracer_fd);
2426 break;
2427 case LTTNG_KERNEL_ALL:
2428 /* Enable syscalls and tracepoints */
2429 ret = event_kernel_enable_all(session->kernel_session,
2430 kchan, kernel_tracer_fd);
2431 break;
2432 default:
2433 ret = LTTCOMM_KERN_ENABLE_FAIL;
2434 goto error;
2435 }
2436 if (ret != LTTCOMM_OK) {
2437 goto error;
2438 }
2439
2440 kernel_wait_quiescent(kernel_tracer_fd);
2441 break;
2442 default:
2443 /* TODO: Userspace tracing */
2444 ret = LTTCOMM_NOT_IMPLEMENTED;
2445 goto error;
2446 }
2447
2448 ret = LTTCOMM_OK;
2449
2450 error:
2451 return ret;
2452 }
2453
2454 /*
2455 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2456 */
2457 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2458 {
2459 int ret;
2460 ssize_t nb_events = 0;
2461
2462 switch (domain) {
2463 case LTTNG_DOMAIN_KERNEL:
2464 nb_events = kernel_list_events(kernel_tracer_fd, events);
2465 if (nb_events < 0) {
2466 ret = LTTCOMM_KERN_LIST_FAIL;
2467 goto error;
2468 }
2469 break;
2470 case LTTNG_DOMAIN_UST:
2471 nb_events = ust_app_list_events(events);
2472 if (nb_events < 0) {
2473 ret = LTTCOMM_UST_LIST_FAIL;
2474 goto error;
2475 }
2476 break;
2477 default:
2478 ret = LTTCOMM_NOT_IMPLEMENTED;
2479 goto error;
2480 }
2481
2482 return nb_events;
2483
2484 error:
2485 /* Return negative value to differentiate return code */
2486 return -ret;
2487 }
2488
2489 /*
2490 * Command LTTNG_START_TRACE processed by the client thread.
2491 */
2492 static int cmd_start_trace(struct ltt_session *session)
2493 {
2494 int ret;
2495 struct ltt_kernel_session *ksession;
2496 struct ltt_ust_session *usess = session->ust_session;
2497
2498 /* Short cut */
2499 ksession = session->kernel_session;
2500
2501 /* Kernel tracing */
2502 if (ksession != NULL) {
2503 struct ltt_kernel_channel *kchan;
2504
2505 /* Open kernel metadata */
2506 if (ksession->metadata == NULL) {
2507 ret = kernel_open_metadata(ksession, ksession->trace_path);
2508 if (ret < 0) {
2509 ret = LTTCOMM_KERN_META_FAIL;
2510 goto error;
2511 }
2512 }
2513
2514 /* Open kernel metadata stream */
2515 if (ksession->metadata_stream_fd == 0) {
2516 ret = kernel_open_metadata_stream(ksession);
2517 if (ret < 0) {
2518 ERR("Kernel create metadata stream failed");
2519 ret = LTTCOMM_KERN_STREAM_FAIL;
2520 goto error;
2521 }
2522 }
2523
2524 /* For each channel */
2525 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2526 if (kchan->stream_count == 0) {
2527 ret = kernel_open_channel_stream(kchan);
2528 if (ret < 0) {
2529 ret = LTTCOMM_KERN_STREAM_FAIL;
2530 goto error;
2531 }
2532 /* Update the stream global counter */
2533 ksession->stream_count_global += ret;
2534 }
2535 }
2536
2537 /* Setup kernel consumer socket and send fds to it */
2538 ret = init_kernel_tracing(ksession);
2539 if (ret < 0) {
2540 ret = LTTCOMM_KERN_START_FAIL;
2541 goto error;
2542 }
2543
2544 /* This start the kernel tracing */
2545 ret = kernel_start_session(ksession);
2546 if (ret < 0) {
2547 ret = LTTCOMM_KERN_START_FAIL;
2548 goto error;
2549 }
2550
2551 /* Quiescent wait after starting trace */
2552 kernel_wait_quiescent(kernel_tracer_fd);
2553 }
2554
2555 /* Flag session that trace should start automatically */
2556 usess->start_trace = 1;
2557
2558 ret = ust_app_start_trace_all(usess);
2559 if (ret < 0) {
2560 ret = LTTCOMM_UST_START_FAIL;
2561 goto error;
2562 }
2563
2564 ret = LTTCOMM_OK;
2565
2566 error:
2567 return ret;
2568 }
2569
2570 /*
2571 * Command LTTNG_STOP_TRACE processed by the client thread.
2572 */
2573 static int cmd_stop_trace(struct ltt_session *session)
2574 {
2575 int ret;
2576 struct ltt_kernel_channel *kchan;
2577 struct ltt_kernel_session *ksession;
2578 //struct ltt_ust_session *usess;
2579 //struct ltt_ust_channel *ustchan;
2580
2581 /* Short cut */
2582 ksession = session->kernel_session;
2583
2584 /* Kernel tracer */
2585 if (ksession != NULL) {
2586 DBG("Stop kernel tracing");
2587
2588 /* Flush all buffers before stopping */
2589 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2590 if (ret < 0) {
2591 ERR("Kernel metadata flush failed");
2592 }
2593
2594 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2595 ret = kernel_flush_buffer(kchan);
2596 if (ret < 0) {
2597 ERR("Kernel flush buffer error");
2598 }
2599 }
2600
2601 ret = kernel_stop_session(ksession);
2602 if (ret < 0) {
2603 ret = LTTCOMM_KERN_STOP_FAIL;
2604 goto error;
2605 }
2606
2607 kernel_wait_quiescent(kernel_tracer_fd);
2608 }
2609
2610 #ifdef DISABLE
2611 /* Stop each UST session */
2612 DBG("Stop UST tracing");
2613 cds_list_for_each_entry(usess, &session->ust_session_list.head, list) {
2614 /* Flush all buffers before stopping */
2615 ret = ustctl_flush_buffer(usess->sock, usess->metadata->obj);
2616 if (ret < 0) {
2617 ERR("UST metadata flush failed");
2618 }
2619
2620 cds_list_for_each_entry(ustchan, &usess->channels.head, list) {
2621 ret = ustctl_flush_buffer(usess->sock, ustchan->obj);
2622 if (ret < 0) {
2623 ERR("UST flush buffer error");
2624 }
2625 }
2626
2627 ret = ustctl_stop_session(usess->sock, usess->handle);
2628 if (ret < 0) {
2629 ret = LTTCOMM_KERN_STOP_FAIL;
2630 goto error;
2631 }
2632
2633 ustctl_wait_quiescent(usess->sock);
2634 }
2635 #endif
2636
2637 ret = LTTCOMM_OK;
2638
2639 error:
2640 return ret;
2641 }
2642
2643 /*
2644 * Command LTTNG_CREATE_SESSION processed by the client thread.
2645 */
2646 static int cmd_create_session(char *name, char *path)
2647 {
2648 int ret;
2649
2650 ret = session_create(name, path);
2651 if (ret != LTTCOMM_OK) {
2652 goto error;
2653 }
2654
2655 ret = LTTCOMM_OK;
2656
2657 error:
2658 return ret;
2659 }
2660
2661 /*
2662 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2663 */
2664 static int cmd_destroy_session(struct ltt_session *session, char *name)
2665 {
2666 int ret;
2667
2668 /* Clean kernel session teardown */
2669 teardown_kernel_session(session);
2670
2671 /*
2672 * Must notify the kernel thread here to update it's poll setin order
2673 * to remove the channel(s)' fd just destroyed.
2674 */
2675 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2676 if (ret < 0) {
2677 perror("write kernel poll pipe");
2678 }
2679
2680 ret = session_destroy(session);
2681
2682 return ret;
2683 }
2684
2685 /*
2686 * Command LTTNG_CALIBRATE processed by the client thread.
2687 */
2688 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2689 {
2690 int ret;
2691
2692 switch (domain) {
2693 case LTTNG_DOMAIN_KERNEL:
2694 {
2695 struct lttng_kernel_calibrate kcalibrate;
2696
2697 kcalibrate.type = calibrate->type;
2698 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2699 if (ret < 0) {
2700 ret = LTTCOMM_KERN_ENABLE_FAIL;
2701 goto error;
2702 }
2703 break;
2704 }
2705 default:
2706 /* TODO: Userspace tracing */
2707 ret = LTTCOMM_NOT_IMPLEMENTED;
2708 goto error;
2709 }
2710
2711 ret = LTTCOMM_OK;
2712
2713 error:
2714 return ret;
2715 }
2716
2717 /*
2718 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2719 */
2720 static int cmd_register_consumer(struct ltt_session *session, int domain,
2721 char *sock_path)
2722 {
2723 int ret, sock;
2724
2725 switch (domain) {
2726 case LTTNG_DOMAIN_KERNEL:
2727 /* Can't register a consumer if there is already one */
2728 if (session->kernel_session->consumer_fd != 0) {
2729 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2730 goto error;
2731 }
2732
2733 sock = lttcomm_connect_unix_sock(sock_path);
2734 if (sock < 0) {
2735 ret = LTTCOMM_CONNECT_FAIL;
2736 goto error;
2737 }
2738
2739 session->kernel_session->consumer_fd = sock;
2740 break;
2741 default:
2742 /* TODO: Userspace tracing */
2743 ret = LTTCOMM_NOT_IMPLEMENTED;
2744 goto error;
2745 }
2746
2747 ret = LTTCOMM_OK;
2748
2749 error:
2750 return ret;
2751 }
2752
2753 /*
2754 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2755 */
2756 static ssize_t cmd_list_domains(struct ltt_session *session,
2757 struct lttng_domain **domains)
2758 {
2759 int ret, index = 0;
2760 ssize_t nb_dom = 0;
2761
2762 if (session->kernel_session != NULL) {
2763 DBG3("Listing domains found kernel domain");
2764 nb_dom++;
2765 }
2766
2767 if (session->ust_session != NULL) {
2768 DBG3("Listing domains found UST global domain");
2769 nb_dom++;
2770 }
2771
2772 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2773 if (*domains == NULL) {
2774 ret = -LTTCOMM_FATAL;
2775 goto error;
2776 }
2777
2778 if (session->kernel_session != NULL) {
2779 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2780 index++;
2781 }
2782
2783 if (session->ust_session != NULL) {
2784 (*domains)[index].type = LTTNG_DOMAIN_UST;
2785 index++;
2786 }
2787
2788 return nb_dom;
2789
2790 error:
2791 return ret;
2792 }
2793
2794 /*
2795 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2796 */
2797 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
2798 struct lttng_channel **channels)
2799 {
2800 int ret;
2801 ssize_t nb_chan = 0;
2802
2803 switch (domain) {
2804 case LTTNG_DOMAIN_KERNEL:
2805 if (session->kernel_session != NULL) {
2806 nb_chan = session->kernel_session->channel_count;
2807 }
2808 DBG3("Number of kernel channels %ld", nb_chan);
2809 break;
2810 case LTTNG_DOMAIN_UST:
2811 if (session->ust_session != NULL) {
2812 nb_chan = hashtable_get_count(
2813 session->ust_session->domain_global.channels);
2814 }
2815 DBG3("Number of UST global channels %ld", nb_chan);
2816 break;
2817 default:
2818 *channels = NULL;
2819 ret = -LTTCOMM_NOT_IMPLEMENTED;
2820 goto error;
2821 }
2822
2823 if (nb_chan > 0) {
2824 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
2825 if (*channels == NULL) {
2826 ret = -LTTCOMM_FATAL;
2827 goto error;
2828 }
2829
2830 list_lttng_channels(domain, session, *channels);
2831 } else {
2832 *channels = NULL;
2833 }
2834
2835 return nb_chan;
2836
2837 error:
2838 return ret;
2839 }
2840
2841 /*
2842 * Command LTTNG_LIST_EVENTS processed by the client thread.
2843 */
2844 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
2845 char *channel_name, struct lttng_event **events)
2846 {
2847 int ret = 0;
2848 ssize_t nb_event = 0;
2849
2850 switch (domain) {
2851 case LTTNG_DOMAIN_KERNEL:
2852 if (session->kernel_session != NULL) {
2853 nb_event = list_lttng_kernel_events(channel_name,
2854 session->kernel_session, events);
2855 }
2856 break;
2857 case LTTNG_DOMAIN_UST:
2858 {
2859 if (session->ust_session != NULL) {
2860 nb_event = list_lttng_ust_global_events(channel_name,
2861 &session->ust_session->domain_global, events);
2862 }
2863 break;
2864 }
2865 default:
2866 ret = -LTTCOMM_NOT_IMPLEMENTED;
2867 goto error;
2868 }
2869
2870 ret = nb_event;
2871
2872 error:
2873 return ret;
2874 }
2875
2876 /*
2877 * Process the command requested by the lttng client within the command
2878 * context structure. This function make sure that the return structure (llm)
2879 * is set and ready for transmission before returning.
2880 *
2881 * Return any error encountered or 0 for success.
2882 */
2883 static int process_client_msg(struct command_ctx *cmd_ctx)
2884 {
2885 int ret = LTTCOMM_OK;
2886 int need_tracing_session = 1;
2887
2888 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
2889
2890 /*
2891 * Check for command that don't needs to allocate a returned payload. We do
2892 * this here so we don't have to make the call for no payload at each
2893 * command.
2894 */
2895 switch(cmd_ctx->lsm->cmd_type) {
2896 case LTTNG_LIST_SESSIONS:
2897 case LTTNG_LIST_TRACEPOINTS:
2898 case LTTNG_LIST_DOMAINS:
2899 case LTTNG_LIST_CHANNELS:
2900 case LTTNG_LIST_EVENTS:
2901 break;
2902 default:
2903 /* Setup lttng message with no payload */
2904 ret = setup_lttng_msg(cmd_ctx, 0);
2905 if (ret < 0) {
2906 /* This label does not try to unlock the session */
2907 goto init_setup_error;
2908 }
2909 }
2910
2911 /* Commands that DO NOT need a session. */
2912 switch (cmd_ctx->lsm->cmd_type) {
2913 case LTTNG_CALIBRATE:
2914 case LTTNG_CREATE_SESSION:
2915 case LTTNG_LIST_SESSIONS:
2916 case LTTNG_LIST_TRACEPOINTS:
2917 need_tracing_session = 0;
2918 break;
2919 default:
2920 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
2921 session_lock_list();
2922 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
2923 session_unlock_list();
2924 if (cmd_ctx->session == NULL) {
2925 if (cmd_ctx->lsm->session.name != NULL) {
2926 ret = LTTCOMM_SESS_NOT_FOUND;
2927 } else {
2928 /* If no session name specified */
2929 ret = LTTCOMM_SELECT_SESS;
2930 }
2931 goto error;
2932 } else {
2933 /* Acquire lock for the session */
2934 session_lock(cmd_ctx->session);
2935 }
2936 break;
2937 }
2938
2939 /*
2940 * Check domain type for specific "pre-action".
2941 */
2942 switch (cmd_ctx->lsm->domain.type) {
2943 case LTTNG_DOMAIN_KERNEL:
2944 /* Kernel tracer check */
2945 if (kernel_tracer_fd == 0) {
2946 /* Basically, load kernel tracer modules */
2947 init_kernel_tracer();
2948 if (kernel_tracer_fd == 0) {
2949 ret = LTTCOMM_KERN_NA;
2950 goto error;
2951 }
2952 }
2953
2954 /* Need a session for kernel command */
2955 if (need_tracing_session) {
2956 if (cmd_ctx->session->kernel_session == NULL) {
2957 ret = create_kernel_session(cmd_ctx->session);
2958 if (ret < 0) {
2959 ret = LTTCOMM_KERN_SESS_FAIL;
2960 goto error;
2961 }
2962 }
2963
2964 /* Start the kernel consumer daemon */
2965 pthread_mutex_lock(&kconsumer_data.pid_mutex);
2966 if (kconsumer_data.pid == 0 &&
2967 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
2968 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2969 ret = start_consumerd(&kconsumer_data);
2970 if (ret < 0) {
2971 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2972 goto error;
2973 }
2974 }
2975 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2976 }
2977 break;
2978 case LTTNG_DOMAIN_UST:
2979 {
2980 if (need_tracing_session) {
2981 if (cmd_ctx->session->ust_session == NULL) {
2982 ret = create_ust_session(cmd_ctx->session,
2983 &cmd_ctx->lsm->domain);
2984 if (ret != LTTCOMM_OK) {
2985 goto error;
2986 }
2987 }
2988 /* Start the kernel consumer daemon */
2989 pthread_mutex_lock(&ustconsumer_data.pid_mutex);
2990 if (ustconsumer_data.pid == 0 &&
2991 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
2992 pthread_mutex_unlock(&ustconsumer_data.pid_mutex);
2993 ret = start_consumerd(&ustconsumer_data);
2994 if (ret < 0) {
2995 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2996 goto error;
2997 }
2998
2999 cmd_ctx->session->ust_session->consumer_fd =
3000 ustconsumer_data.cmd_sock;
3001 }
3002 pthread_mutex_unlock(&ustconsumer_data.pid_mutex);
3003 }
3004 break;
3005 }
3006 default:
3007 break;
3008 }
3009
3010 /* Process by command type */
3011 switch (cmd_ctx->lsm->cmd_type) {
3012 case LTTNG_ADD_CONTEXT:
3013 {
3014 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3015 cmd_ctx->lsm->u.context.channel_name,
3016 cmd_ctx->lsm->u.context.event_name,
3017 &cmd_ctx->lsm->u.context.ctx);
3018 break;
3019 }
3020 case LTTNG_DISABLE_CHANNEL:
3021 {
3022 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3023 cmd_ctx->lsm->u.disable.channel_name);
3024 break;
3025 }
3026 case LTTNG_DISABLE_EVENT:
3027 {
3028 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3029 cmd_ctx->lsm->u.disable.channel_name,
3030 cmd_ctx->lsm->u.disable.name);
3031 ret = LTTCOMM_OK;
3032 break;
3033 }
3034 case LTTNG_DISABLE_ALL_EVENT:
3035 {
3036 DBG("Disabling all events");
3037
3038 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3039 cmd_ctx->lsm->u.disable.channel_name);
3040 break;
3041 }
3042 case LTTNG_ENABLE_CHANNEL:
3043 {
3044 ret = cmd_enable_channel(cmd_ctx->session, &cmd_ctx->lsm->domain,
3045 &cmd_ctx->lsm->u.channel.chan);
3046 break;
3047 }
3048 case LTTNG_ENABLE_EVENT:
3049 {
3050 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3051 cmd_ctx->lsm->u.enable.channel_name,
3052 &cmd_ctx->lsm->u.enable.event);
3053 break;
3054 }
3055 case LTTNG_ENABLE_ALL_EVENT:
3056 {
3057 DBG("Enabling all events");
3058
3059 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3060 cmd_ctx->lsm->u.enable.channel_name,
3061 cmd_ctx->lsm->u.enable.event.type);
3062 break;
3063 }
3064 case LTTNG_LIST_TRACEPOINTS:
3065 {
3066 struct lttng_event *events;
3067 ssize_t nb_events;
3068
3069 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3070 if (nb_events < 0) {
3071 ret = -nb_events;
3072 goto error;
3073 }
3074
3075 /*
3076 * Setup lttng message with payload size set to the event list size in
3077 * bytes and then copy list into the llm payload.
3078 */
3079 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3080 if (ret < 0) {
3081 free(events);
3082 goto setup_error;
3083 }
3084
3085 /* Copy event list into message payload */
3086 memcpy(cmd_ctx->llm->payload, events,
3087 sizeof(struct lttng_event) * nb_events);
3088
3089 free(events);
3090
3091 ret = LTTCOMM_OK;
3092 break;
3093 }
3094 case LTTNG_START_TRACE:
3095 {
3096 ret = cmd_start_trace(cmd_ctx->session);
3097 break;
3098 }
3099 case LTTNG_STOP_TRACE:
3100 {
3101 ret = cmd_stop_trace(cmd_ctx->session);
3102 break;
3103 }
3104 case LTTNG_CREATE_SESSION:
3105 {
3106 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3107 cmd_ctx->lsm->session.path);
3108 break;
3109 }
3110 case LTTNG_DESTROY_SESSION:
3111 {
3112 ret = cmd_destroy_session(cmd_ctx->session,
3113 cmd_ctx->lsm->session.name);
3114 break;
3115 }
3116 case LTTNG_LIST_DOMAINS:
3117 {
3118 ssize_t nb_dom;
3119 struct lttng_domain *domains;
3120
3121 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3122 if (nb_dom < 0) {
3123 ret = -nb_dom;
3124 goto error;
3125 }
3126
3127 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3128 if (ret < 0) {
3129 goto setup_error;
3130 }
3131
3132 /* Copy event list into message payload */
3133 memcpy(cmd_ctx->llm->payload, domains,
3134 nb_dom * sizeof(struct lttng_domain));
3135
3136 free(domains);
3137
3138 ret = LTTCOMM_OK;
3139 break;
3140 }
3141 case LTTNG_LIST_CHANNELS:
3142 {
3143 size_t nb_chan;
3144 struct lttng_channel *channels;
3145
3146 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
3147 cmd_ctx->session, &channels);
3148 if (nb_chan < 0) {
3149 ret = -nb_chan;
3150 goto error;
3151 }
3152
3153 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3154 if (ret < 0) {
3155 goto setup_error;
3156 }
3157
3158 /* Copy event list into message payload */
3159 memcpy(cmd_ctx->llm->payload, channels,
3160 nb_chan * sizeof(struct lttng_channel));
3161
3162 free(channels);
3163
3164 ret = LTTCOMM_OK;
3165 break;
3166 }
3167 case LTTNG_LIST_EVENTS:
3168 {
3169 ssize_t nb_event;
3170 struct lttng_event *events = NULL;
3171
3172 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
3173 cmd_ctx->lsm->u.list.channel_name, &events);
3174 if (nb_event < 0) {
3175 ret = -nb_event;
3176 goto error;
3177 }
3178
3179 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3180 if (ret < 0) {
3181 goto setup_error;
3182 }
3183
3184 /* Copy event list into message payload */
3185 memcpy(cmd_ctx->llm->payload, events,
3186 nb_event * sizeof(struct lttng_event));
3187
3188 free(events);
3189
3190 ret = LTTCOMM_OK;
3191 break;
3192 }
3193 case LTTNG_LIST_SESSIONS:
3194 {
3195 session_lock_list();
3196
3197 if (session_list_ptr->count == 0) {
3198 ret = LTTCOMM_NO_SESSION;
3199 session_unlock_list();
3200 goto error;
3201 }
3202
3203 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) *
3204 session_list_ptr->count);
3205 if (ret < 0) {
3206 session_unlock_list();
3207 goto setup_error;
3208 }
3209
3210 /* Filled the session array */
3211 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
3212
3213 session_unlock_list();
3214
3215 ret = LTTCOMM_OK;
3216 break;
3217 }
3218 case LTTNG_CALIBRATE:
3219 {
3220 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3221 &cmd_ctx->lsm->u.calibrate);
3222 break;
3223 }
3224 case LTTNG_REGISTER_CONSUMER:
3225 {
3226 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3227 cmd_ctx->lsm->u.reg.path);
3228 break;
3229 }
3230 default:
3231 ret = LTTCOMM_UND;
3232 break;
3233 }
3234
3235 error:
3236 if (cmd_ctx->llm == NULL) {
3237 DBG("Missing llm structure. Allocating one.");
3238 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3239 goto setup_error;
3240 }
3241 }
3242 /* Set return code */
3243 cmd_ctx->llm->ret_code = ret;
3244 setup_error:
3245 if (cmd_ctx->session) {
3246 session_unlock(cmd_ctx->session);
3247 }
3248 init_setup_error:
3249 return ret;
3250 }
3251
3252 /*
3253 * This thread manage all clients request using the unix client socket for
3254 * communication.
3255 */
3256 static void *thread_manage_clients(void *data)
3257 {
3258 int sock = 0, ret, i, pollfd;
3259 uint32_t revents, nb_fd;
3260 struct command_ctx *cmd_ctx = NULL;
3261 struct lttng_poll_event events;
3262
3263 DBG("[thread] Manage client started");
3264
3265 rcu_register_thread();
3266
3267 ret = lttcomm_listen_unix_sock(client_sock);
3268 if (ret < 0) {
3269 goto error;
3270 }
3271
3272 /*
3273 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3274 * more will be added to this poll set.
3275 */
3276 ret = create_thread_poll_set(&events, 2);
3277 if (ret < 0) {
3278 goto error;
3279 }
3280
3281 /* Add the application registration socket */
3282 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3283 if (ret < 0) {
3284 goto error;
3285 }
3286
3287 /*
3288 * Notify parent pid that we are ready to accept command for client side.
3289 */
3290 if (opt_sig_parent) {
3291 kill(ppid, SIGCHLD);
3292 }
3293
3294 while (1) {
3295 DBG("Accepting client command ...");
3296
3297 nb_fd = LTTNG_POLL_GETNB(&events);
3298
3299 /* Inifinite blocking call, waiting for transmission */
3300 ret = lttng_poll_wait(&events, -1);
3301 if (ret < 0) {
3302 goto error;
3303 }
3304
3305 for (i = 0; i < nb_fd; i++) {
3306 /* Fetch once the poll data */
3307 revents = LTTNG_POLL_GETEV(&events, i);
3308 pollfd = LTTNG_POLL_GETFD(&events, i);
3309
3310 /* Thread quit pipe has been closed. Killing thread. */
3311 ret = check_thread_quit_pipe(pollfd, revents);
3312 if (ret) {
3313 goto error;
3314 }
3315
3316 /* Event on the registration socket */
3317 if (pollfd == client_sock) {
3318 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3319 ERR("Client socket poll error");
3320 goto error;
3321 }
3322 }
3323 }
3324
3325 DBG("Wait for client response");
3326
3327 sock = lttcomm_accept_unix_sock(client_sock);
3328 if (sock < 0) {
3329 goto error;
3330 }
3331
3332 /* Allocate context command to process the client request */
3333 cmd_ctx = malloc(sizeof(struct command_ctx));
3334 if (cmd_ctx == NULL) {
3335 perror("malloc cmd_ctx");
3336 goto error;
3337 }
3338
3339 /* Allocate data buffer for reception */
3340 cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
3341 if (cmd_ctx->lsm == NULL) {
3342 perror("malloc cmd_ctx->lsm");
3343 goto error;
3344 }
3345
3346 cmd_ctx->llm = NULL;
3347 cmd_ctx->session = NULL;
3348
3349 /*
3350 * Data is received from the lttng client. The struct
3351 * lttcomm_session_msg (lsm) contains the command and data request of
3352 * the client.
3353 */
3354 DBG("Receiving data from client ...");
3355 ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm,