Cleanup ust-app.c and make it more modular
[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 ret = ustctl_register_done(ust_cmd.sock);
1061 if (ret < 0) {
1062 /*
1063 * If the registration is not possible, we simply
1064 * unregister the apps and continue
1065 */
1066 ust_app_unregister(ust_cmd.sock);
1067 } else {
1068 /*
1069 * We just need here to monitor the close of the UST
1070 * socket and poll set monitor those by default.
1071 */
1072 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1073 if (ret < 0) {
1074 goto error;
1075 }
1076
1077 DBG("Apps with sock %d added to poll set",
1078 ust_cmd.sock);
1079 }
1080
1081 /*
1082 * Add channel(s) and event(s) to newly registered apps
1083 * from lttng global UST domain.
1084 */
1085 update_ust_app(ust_cmd.sock);
1086 break;
1087 }
1088 } else {
1089 /*
1090 * At this point, we know that a registered application made
1091 * the event at poll_wait.
1092 */
1093 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1094 /* Removing from the poll set */
1095 ret = lttng_poll_del(&events, pollfd);
1096 if (ret < 0) {
1097 goto error;
1098 }
1099
1100 /* Socket closed */
1101 ust_app_unregister(pollfd);
1102 break;
1103 }
1104 }
1105 }
1106 }
1107
1108 error:
1109 DBG("Application communication apps dying");
1110 close(apps_cmd_pipe[0]);
1111 close(apps_cmd_pipe[1]);
1112
1113 lttng_poll_clean(&events);
1114
1115 rcu_thread_offline();
1116 rcu_unregister_thread();
1117 return NULL;
1118 }
1119
1120 /*
1121 * Dispatch request from the registration threads to the application
1122 * communication thread.
1123 */
1124 static void *thread_dispatch_ust_registration(void *data)
1125 {
1126 int ret;
1127 struct cds_wfq_node *node;
1128 struct ust_command *ust_cmd = NULL;
1129
1130 DBG("[thread] Dispatch UST command started");
1131
1132 while (!dispatch_thread_exit) {
1133 /* Atomically prepare the queue futex */
1134 futex_nto1_prepare(&ust_cmd_queue.futex);
1135
1136 do {
1137 /* Dequeue command for registration */
1138 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1139 if (node == NULL) {
1140 DBG("Woken up but nothing in the UST command queue");
1141 /* Continue thread execution */
1142 break;
1143 }
1144
1145 ust_cmd = caa_container_of(node, struct ust_command, node);
1146
1147 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1148 " gid:%d sock:%d name:%s (version %d.%d)",
1149 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1150 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1151 ust_cmd->sock, ust_cmd->reg_msg.name,
1152 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1153 /*
1154 * Inform apps thread of the new application registration. This
1155 * call is blocking so we can be assured that the data will be read
1156 * at some point in time or wait to the end of the world :)
1157 */
1158 ret = write(apps_cmd_pipe[1], ust_cmd,
1159 sizeof(struct ust_command));
1160 if (ret < 0) {
1161 perror("write apps cmd pipe");
1162 if (errno == EBADF) {
1163 /*
1164 * We can't inform the application thread to process
1165 * registration. We will exit or else application
1166 * registration will not occur and tracing will never
1167 * start.
1168 */
1169 goto error;
1170 }
1171 }
1172 free(ust_cmd);
1173 } while (node != NULL);
1174
1175 /* Futex wait on queue. Blocking call on futex() */
1176 futex_nto1_wait(&ust_cmd_queue.futex);
1177 }
1178
1179 error:
1180 DBG("Dispatch thread dying");
1181 return NULL;
1182 }
1183
1184 /*
1185 * This thread manage application registration.
1186 */
1187 static void *thread_registration_apps(void *data)
1188 {
1189 int sock = 0, i, ret, pollfd;
1190 uint32_t revents, nb_fd;
1191 struct lttng_poll_event events;
1192 /*
1193 * Get allocated in this thread, enqueued to a global queue, dequeued and
1194 * freed in the manage apps thread.
1195 */
1196 struct ust_command *ust_cmd = NULL;
1197
1198 DBG("[thread] Manage application registration started");
1199
1200 ret = lttcomm_listen_unix_sock(apps_sock);
1201 if (ret < 0) {
1202 goto error;
1203 }
1204
1205 /*
1206 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1207 * more will be added to this poll set.
1208 */
1209 ret = create_thread_poll_set(&events, 2);
1210 if (ret < 0) {
1211 goto error;
1212 }
1213
1214 /* Add the application registration socket */
1215 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1216 if (ret < 0) {
1217 goto error;
1218 }
1219
1220 /* Notify all applications to register */
1221 ret = notify_ust_apps(1);
1222 if (ret < 0) {
1223 ERR("Failed to notify applications or create the wait shared memory.\n"
1224 "Execution continues but there might be problem for already\n"
1225 "running applications that wishes to register.");
1226 }
1227
1228 while (1) {
1229 DBG("Accepting application registration");
1230
1231 nb_fd = LTTNG_POLL_GETNB(&events);
1232
1233 /* Inifinite blocking call, waiting for transmission */
1234 ret = lttng_poll_wait(&events, -1);
1235 if (ret < 0) {
1236 goto error;
1237 }
1238
1239 for (i = 0; i < nb_fd; i++) {
1240 /* Fetch once the poll data */
1241 revents = LTTNG_POLL_GETEV(&events, i);
1242 pollfd = LTTNG_POLL_GETFD(&events, i);
1243
1244 /* Thread quit pipe has been closed. Killing thread. */
1245 ret = check_thread_quit_pipe(pollfd, revents);
1246 if (ret) {
1247 goto error;
1248 }
1249
1250 /* Event on the registration socket */
1251 if (pollfd == apps_sock) {
1252 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1253 ERR("Register apps socket poll error");
1254 goto error;
1255 } else if (revents & LPOLLIN) {
1256 sock = lttcomm_accept_unix_sock(apps_sock);
1257 if (sock < 0) {
1258 goto error;
1259 }
1260
1261 /* Create UST registration command for enqueuing */
1262 ust_cmd = malloc(sizeof(struct ust_command));
1263 if (ust_cmd == NULL) {
1264 perror("ust command malloc");
1265 goto error;
1266 }
1267
1268 /*
1269 * Using message-based transmissions to ensure we don't
1270 * have to deal with partially received messages.
1271 */
1272 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1273 sizeof(struct ust_register_msg));
1274 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1275 if (ret < 0) {
1276 perror("lttcomm_recv_unix_sock register apps");
1277 } else {
1278 ERR("Wrong size received on apps register");
1279 }
1280 free(ust_cmd);
1281 close(sock);
1282 continue;
1283 }
1284
1285 ust_cmd->sock = sock;
1286
1287 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1288 " gid:%d sock:%d name:%s (version %d.%d)",
1289 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1290 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1291 ust_cmd->sock, ust_cmd->reg_msg.name,
1292 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1293
1294 /*
1295 * Lock free enqueue the registration request. The red pill
1296 * has been taken! This apps will be part of the *system*.
1297 */
1298 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1299
1300 /*
1301 * Wake the registration queue futex. Implicit memory
1302 * barrier with the exchange in cds_wfq_enqueue.
1303 */
1304 futex_nto1_wake(&ust_cmd_queue.futex);
1305 }
1306 }
1307 }
1308 }
1309
1310 error:
1311 DBG("UST Registration thread dying");
1312
1313 /* Notify that the registration thread is gone */
1314 notify_ust_apps(0);
1315
1316 close(apps_sock);
1317 close(sock);
1318 unlink(apps_unix_sock_path);
1319
1320 lttng_poll_clean(&events);
1321
1322 return NULL;
1323 }
1324
1325 /*
1326 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1327 * exec or it will fails.
1328 */
1329 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1330 {
1331 int ret;
1332 struct timespec timeout;
1333
1334 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1335 timeout.tv_nsec = 0;
1336
1337 /* Setup semaphore */
1338 ret = sem_init(&consumer_data->sem, 0, 0);
1339 if (ret < 0) {
1340 PERROR("sem_init consumer semaphore");
1341 goto error;
1342 }
1343
1344 ret = pthread_create(&consumer_data->thread, NULL,
1345 thread_manage_consumer, consumer_data);
1346 if (ret != 0) {
1347 PERROR("pthread_create consumer");
1348 ret = -1;
1349 goto error;
1350 }
1351
1352 /* Get time for sem_timedwait absolute timeout */
1353 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1354 if (ret < 0) {
1355 PERROR("clock_gettime spawn consumer");
1356 /* Infinite wait for the kconsumerd thread to be ready */
1357 ret = sem_wait(&consumer_data->sem);
1358 } else {
1359 /* Normal timeout if the gettime was successful */
1360 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1361 ret = sem_timedwait(&consumer_data->sem, &timeout);
1362 }
1363
1364 if (ret < 0) {
1365 if (errno == ETIMEDOUT) {
1366 /*
1367 * Call has timed out so we kill the kconsumerd_thread and return
1368 * an error.
1369 */
1370 ERR("The consumer thread was never ready. Killing it");
1371 ret = pthread_cancel(consumer_data->thread);
1372 if (ret < 0) {
1373 PERROR("pthread_cancel consumer thread");
1374 }
1375 } else {
1376 PERROR("semaphore wait failed consumer thread");
1377 }
1378 goto error;
1379 }
1380
1381 pthread_mutex_lock(&consumer_data->pid_mutex);
1382 if (consumer_data->pid == 0) {
1383 ERR("Kconsumerd did not start");
1384 pthread_mutex_unlock(&consumer_data->pid_mutex);
1385 goto error;
1386 }
1387 pthread_mutex_unlock(&consumer_data->pid_mutex);
1388
1389 return 0;
1390
1391 error:
1392 return ret;
1393 }
1394
1395 /*
1396 * Join consumer thread
1397 */
1398 static int join_consumer_thread(struct consumer_data *consumer_data)
1399 {
1400 void *status;
1401 int ret;
1402
1403 if (consumer_data->pid != 0) {
1404 ret = kill(consumer_data->pid, SIGTERM);
1405 if (ret) {
1406 ERR("Error killing consumer daemon");
1407 return ret;
1408 }
1409 return pthread_join(consumer_data->thread, &status);
1410 } else {
1411 return 0;
1412 }
1413 }
1414
1415 /*
1416 * Fork and exec a consumer daemon (consumerd).
1417 *
1418 * Return pid if successful else -1.
1419 */
1420 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1421 {
1422 int ret;
1423 pid_t pid;
1424 const char *verbosity;
1425
1426 DBG("Spawning consumerd");
1427
1428 pid = fork();
1429 if (pid == 0) {
1430 /*
1431 * Exec consumerd.
1432 */
1433 if (opt_verbose > 1 || opt_verbose_consumer) {
1434 verbosity = "--verbose";
1435 } else {
1436 verbosity = "--quiet";
1437 }
1438 switch (consumer_data->type) {
1439 case LTTNG_CONSUMER_KERNEL:
1440 execl(INSTALL_BIN_PATH "/lttng-consumerd",
1441 "lttng-consumerd", verbosity, "-k", NULL);
1442 break;
1443 case LTTNG_CONSUMER_UST:
1444 execl(INSTALL_BIN_PATH "/lttng-consumerd",
1445 "lttng-consumerd", verbosity, "-u", NULL);
1446 break;
1447 default:
1448 perror("unknown consumer type");
1449 exit(EXIT_FAILURE);
1450 }
1451 if (errno != 0) {
1452 perror("kernel start consumer exec");
1453 }
1454 exit(EXIT_FAILURE);
1455 } else if (pid > 0) {
1456 ret = pid;
1457 } else {
1458 perror("start consumer fork");
1459 ret = -errno;
1460 }
1461 return ret;
1462 }
1463
1464 /*
1465 * Spawn the consumerd daemon and session daemon thread.
1466 */
1467 static int start_consumerd(struct consumer_data *consumer_data)
1468 {
1469 int ret;
1470
1471 pthread_mutex_lock(&consumer_data->pid_mutex);
1472 if (consumer_data->pid != 0) {
1473 pthread_mutex_unlock(&consumer_data->pid_mutex);
1474 goto end;
1475 }
1476
1477 ret = spawn_consumerd(consumer_data);
1478 if (ret < 0) {
1479 ERR("Spawning consumerd failed");
1480 pthread_mutex_unlock(&consumer_data->pid_mutex);
1481 goto error;
1482 }
1483
1484 /* Setting up the consumer_data pid */
1485 consumer_data->pid = ret;
1486 DBG2("Consumer pid %d", consumer_data->pid);
1487 pthread_mutex_unlock(&consumer_data->pid_mutex);
1488
1489 DBG2("Spawning consumer control thread");
1490 ret = spawn_consumer_thread(consumer_data);
1491 if (ret < 0) {
1492 ERR("Fatal error spawning consumer control thread");
1493 goto error;
1494 }
1495
1496 end:
1497 return 0;
1498
1499 error:
1500 return ret;
1501 }
1502
1503 /*
1504 * modprobe_kernel_modules
1505 */
1506 static int modprobe_kernel_modules(void)
1507 {
1508 int ret = 0, i;
1509 char modprobe[256];
1510
1511 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1512 ret = snprintf(modprobe, sizeof(modprobe),
1513 "/sbin/modprobe %s%s",
1514 kernel_modules_list[i].required ? "" : "-q ",
1515 kernel_modules_list[i].name);
1516 if (ret < 0) {
1517 perror("snprintf modprobe");
1518 goto error;
1519 }
1520 modprobe[sizeof(modprobe) - 1] = '\0';
1521 ret = system(modprobe);
1522 if (ret == -1) {
1523 ERR("Unable to launch modprobe for module %s",
1524 kernel_modules_list[i].name);
1525 } else if (kernel_modules_list[i].required
1526 && WEXITSTATUS(ret) != 0) {
1527 ERR("Unable to load module %s",
1528 kernel_modules_list[i].name);
1529 } else {
1530 DBG("Modprobe successfully %s",
1531 kernel_modules_list[i].name);
1532 }
1533 }
1534
1535 error:
1536 return ret;
1537 }
1538
1539 /*
1540 * mount_debugfs
1541 */
1542 static int mount_debugfs(char *path)
1543 {
1544 int ret;
1545 char *type = "debugfs";
1546
1547 ret = mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1548 if (ret < 0) {
1549 PERROR("Cannot create debugfs path");
1550 goto error;
1551 }
1552
1553 ret = mount(type, path, type, 0, NULL);
1554 if (ret < 0) {
1555 PERROR("Cannot mount debugfs");
1556 goto error;
1557 }
1558
1559 DBG("Mounted debugfs successfully at %s", path);
1560
1561 error:
1562 return ret;
1563 }
1564
1565 /*
1566 * Setup necessary data for kernel tracer action.
1567 */
1568 static void init_kernel_tracer(void)
1569 {
1570 int ret;
1571 char *proc_mounts = "/proc/mounts";
1572 char line[256];
1573 char *debugfs_path = NULL, *lttng_path = NULL;
1574 FILE *fp;
1575
1576 /* Detect debugfs */
1577 fp = fopen(proc_mounts, "r");
1578 if (fp == NULL) {
1579 ERR("Unable to probe %s", proc_mounts);
1580 goto error;
1581 }
1582
1583 while (fgets(line, sizeof(line), fp) != NULL) {
1584 if (strstr(line, "debugfs") != NULL) {
1585 /* Remove first string */
1586 strtok(line, " ");
1587 /* Dup string here so we can reuse line later on */
1588 debugfs_path = strdup(strtok(NULL, " "));
1589 DBG("Got debugfs path : %s", debugfs_path);
1590 break;
1591 }
1592 }
1593
1594 fclose(fp);
1595
1596 /* Mount debugfs if needded */
1597 if (debugfs_path == NULL) {
1598 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1599 if (ret < 0) {
1600 perror("asprintf debugfs path");
1601 goto error;
1602 }
1603 ret = mount_debugfs(debugfs_path);
1604 if (ret < 0) {
1605 perror("Cannot mount debugfs");
1606 goto error;
1607 }
1608 }
1609
1610 /* Modprobe lttng kernel modules */
1611 ret = modprobe_kernel_modules();
1612 if (ret < 0) {
1613 goto error;
1614 }
1615
1616 /* Setup lttng kernel path */
1617 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1618 if (ret < 0) {
1619 perror("asprintf lttng path");
1620 goto error;
1621 }
1622
1623 /* Open debugfs lttng */
1624 kernel_tracer_fd = open(lttng_path, O_RDWR);
1625 if (kernel_tracer_fd < 0) {
1626 DBG("Failed to open %s", lttng_path);
1627 goto error;
1628 }
1629
1630 free(lttng_path);
1631 free(debugfs_path);
1632 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1633 return;
1634
1635 error:
1636 if (lttng_path) {
1637 free(lttng_path);
1638 }
1639 if (debugfs_path) {
1640 free(debugfs_path);
1641 }
1642 WARN("No kernel tracer available");
1643 kernel_tracer_fd = 0;
1644 return;
1645 }
1646
1647 /*
1648 * Init tracing by creating trace directory and sending fds kernel consumer.
1649 */
1650 static int init_kernel_tracing(struct ltt_kernel_session *session)
1651 {
1652 int ret = 0;
1653
1654 if (session->consumer_fds_sent == 0) {
1655 /*
1656 * Assign default kernel consumer socket if no consumer assigned to the
1657 * kernel session. At this point, it's NOT suppose to be 0 but this is
1658 * an extra security check.
1659 */
1660 if (session->consumer_fd == 0) {
1661 session->consumer_fd = kconsumer_data.cmd_sock;
1662 }
1663
1664 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1665 if (ret < 0) {
1666 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1667 goto error;
1668 }
1669
1670 session->consumer_fds_sent = 1;
1671 }
1672
1673 error:
1674 return ret;
1675 }
1676
1677 /*
1678 * Create an UST session and add it to the session ust list.
1679 */
1680 static int create_ust_session(struct ltt_session *session,
1681 struct lttng_domain *domain)
1682 {
1683 int ret;
1684 unsigned int uid;
1685 struct ltt_ust_session *lus = NULL;
1686
1687 switch (domain->type) {
1688 case LTTNG_DOMAIN_UST:
1689 break;
1690 default:
1691 ret = LTTCOMM_UNKNOWN_DOMAIN;
1692 goto error;
1693 }
1694
1695 DBG("Creating UST session");
1696
1697 session_lock_list();
1698 uid = session_list_ptr->count;
1699 session_unlock_list();
1700
1701 lus = trace_ust_create_session(session->path, uid, domain);
1702 if (lus == NULL) {
1703 ret = LTTCOMM_UST_SESS_FAIL;
1704 goto error;
1705 }
1706
1707 ret = mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1708 geteuid(), allowed_group());
1709 if (ret < 0) {
1710 if (ret != -EEXIST) {
1711 ERR("Trace directory creation error");
1712 ret = LTTCOMM_UST_SESS_FAIL;
1713 goto error;
1714 }
1715 }
1716
1717 /* The domain type dictate different actions on session creation */
1718 switch (domain->type) {
1719 case LTTNG_DOMAIN_UST:
1720 /* No ustctl for the global UST domain */
1721 break;
1722 default:
1723 ERR("Unknown UST domain on create session %d", domain->type);
1724 goto error;
1725 }
1726 session->ust_session = lus;
1727
1728 return LTTCOMM_OK;
1729
1730 error:
1731 free(lus);
1732 return ret;
1733 }
1734
1735 /*
1736 * Create a kernel tracer session then create the default channel.
1737 */
1738 static int create_kernel_session(struct ltt_session *session)
1739 {
1740 int ret;
1741
1742 DBG("Creating kernel session");
1743
1744 ret = kernel_create_session(session, kernel_tracer_fd);
1745 if (ret < 0) {
1746 ret = LTTCOMM_KERN_SESS_FAIL;
1747 goto error;
1748 }
1749
1750 /* Set kernel consumer socket fd */
1751 if (kconsumer_data.cmd_sock) {
1752 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1753 }
1754
1755 ret = mkdir_recursive(session->kernel_session->trace_path,
1756 S_IRWXU | S_IRWXG, geteuid(), allowed_group());
1757 if (ret < 0) {
1758 if (ret != -EEXIST) {
1759 ERR("Trace directory creation error");
1760 goto error;
1761 }
1762 }
1763
1764 error:
1765 return ret;
1766 }
1767
1768 /*
1769 * Using the session list, filled a lttng_session array to send back to the
1770 * client for session listing.
1771 *
1772 * The session list lock MUST be acquired before calling this function. Use
1773 * session_lock_list() and session_unlock_list().
1774 */
1775 static void list_lttng_sessions(struct lttng_session *sessions)
1776 {
1777 int i = 0;
1778 struct ltt_session *session;
1779
1780 DBG("Getting all available session");
1781 /*
1782 * Iterate over session list and append data after the control struct in
1783 * the buffer.
1784 */
1785 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1786 strncpy(sessions[i].path, session->path, PATH_MAX);
1787 sessions[i].path[PATH_MAX - 1] = '\0';
1788 strncpy(sessions[i].name, session->name, NAME_MAX);
1789 sessions[i].name[NAME_MAX - 1] = '\0';
1790 i++;
1791 }
1792 }
1793
1794 /*
1795 * Fill lttng_channel array of all channels.
1796 */
1797 static void list_lttng_channels(struct ltt_session *session,
1798 struct lttng_channel *channels)
1799 {
1800 int i = 0;
1801 struct ltt_kernel_channel *kchan;
1802
1803 DBG("Listing channels for session %s", session->name);
1804
1805 /* Kernel channels */
1806 if (session->kernel_session != NULL) {
1807 cds_list_for_each_entry(kchan,
1808 &session->kernel_session->channel_list.head, list) {
1809 /* Copy lttng_channel struct to array */
1810 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
1811 channels[i].enabled = kchan->enabled;
1812 i++;
1813 }
1814 }
1815
1816 /* TODO: Missing UST listing */
1817 }
1818
1819 /*
1820 * Fill lttng_event array of all events in the channel.
1821 */
1822 static void list_lttng_events(struct ltt_kernel_channel *kchan,
1823 struct lttng_event *events)
1824 {
1825 /*
1826 * TODO: This is ONLY kernel. Need UST support.
1827 */
1828 int i = 0;
1829 struct ltt_kernel_event *event;
1830
1831 DBG("Listing events for channel %s", kchan->channel->name);
1832
1833 /* Kernel channels */
1834 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
1835 strncpy(events[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
1836 events[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
1837 events[i].enabled = event->enabled;
1838 switch (event->event->instrumentation) {
1839 case LTTNG_KERNEL_TRACEPOINT:
1840 events[i].type = LTTNG_EVENT_TRACEPOINT;
1841 break;
1842 case LTTNG_KERNEL_KPROBE:
1843 case LTTNG_KERNEL_KRETPROBE:
1844 events[i].type = LTTNG_EVENT_PROBE;
1845 memcpy(&events[i].attr.probe, &event->event->u.kprobe,
1846 sizeof(struct lttng_kernel_kprobe));
1847 break;
1848 case LTTNG_KERNEL_FUNCTION:
1849 events[i].type = LTTNG_EVENT_FUNCTION;
1850 memcpy(&events[i].attr.ftrace, &event->event->u.ftrace,
1851 sizeof(struct lttng_kernel_function));
1852 break;
1853 case LTTNG_KERNEL_NOOP:
1854 events[i].type = LTTNG_EVENT_NOOP;
1855 break;
1856 case LTTNG_KERNEL_SYSCALL:
1857 events[i].type = LTTNG_EVENT_SYSCALL;
1858 break;
1859 case LTTNG_KERNEL_ALL:
1860 assert(0);
1861 break;
1862 }
1863 i++;
1864 }
1865 }
1866
1867 /*
1868 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1869 */
1870 static int cmd_disable_channel(struct ltt_session *session,
1871 int domain, char *channel_name)
1872 {
1873 int ret;
1874
1875 switch (domain) {
1876 case LTTNG_DOMAIN_KERNEL:
1877 ret = channel_kernel_disable(session->kernel_session,
1878 channel_name);
1879 if (ret != LTTCOMM_OK) {
1880 goto error;
1881 }
1882
1883 kernel_wait_quiescent(kernel_tracer_fd);
1884 break;
1885 case LTTNG_DOMAIN_UST_PID:
1886 break;
1887 default:
1888 ret = LTTCOMM_UNKNOWN_DOMAIN;
1889 goto error;
1890 }
1891
1892 ret = LTTCOMM_OK;
1893
1894 error:
1895 return ret;
1896 }
1897
1898 /*
1899 * Copy channel from attributes and set it in the application channel list.
1900 */
1901 /*
1902 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
1903 struct lttng_channel *attr, struct ust_app *app)
1904 {
1905 int ret;
1906 struct ltt_ust_channel *uchan, *new_chan;
1907
1908 uchan = trace_ust_get_channel_by_key(usess->channels, attr->name);
1909 if (uchan == NULL) {
1910 ret = LTTCOMM_FATAL;
1911 goto error;
1912 }
1913
1914 new_chan = trace_ust_create_channel(attr, usess->path);
1915 if (new_chan == NULL) {
1916 PERROR("malloc ltt_ust_channel");
1917 ret = LTTCOMM_FATAL;
1918 goto error;
1919 }
1920
1921 ret = channel_ust_copy(new_chan, uchan);
1922 if (ret < 0) {
1923 ret = LTTCOMM_FATAL;
1924 goto error;
1925 }
1926
1927 error:
1928 return ret;
1929 }
1930 */
1931
1932 /*
1933 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1934 */
1935 static int cmd_enable_channel(struct ltt_session *session,
1936 struct lttng_domain *domain, struct lttng_channel *attr)
1937 {
1938 int ret;
1939 struct ltt_ust_session *usess = session->ust_session;
1940
1941 DBG("Enabling channel %s for session %s", session->name, attr->name);
1942
1943 switch (domain->type) {
1944 case LTTNG_DOMAIN_KERNEL:
1945 {
1946 struct ltt_kernel_channel *kchan;
1947
1948 kchan = trace_kernel_get_channel_by_name(attr->name,
1949 session->kernel_session);
1950 if (kchan == NULL) {
1951 ret = channel_kernel_create(session->kernel_session,
1952 attr, kernel_poll_pipe[1]);
1953 } else {
1954 ret = channel_kernel_enable(session->kernel_session, kchan);
1955 }
1956
1957 if (ret != LTTCOMM_OK) {
1958 goto error;
1959 }
1960
1961 kernel_wait_quiescent(kernel_tracer_fd);
1962 break;
1963 }
1964 case LTTNG_DOMAIN_UST:
1965 {
1966 struct ltt_ust_channel *uchan;
1967
1968 DBG2("Enabling channel for LTTNG_DOMAIN_UST");
1969
1970 /* Get channel in global UST domain HT */
1971 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
1972 attr->name);
1973 if (uchan == NULL) {
1974 uchan = trace_ust_create_channel(attr, usess->pathname);
1975 if (uchan == NULL) {
1976 ret = LTTCOMM_UST_CHAN_FAIL;
1977 goto error;
1978 }
1979 rcu_read_lock();
1980 hashtable_add_unique(usess->domain_global.channels, &uchan->node);
1981 rcu_read_unlock();
1982 DBG2("UST channel %s added to global domain HT", attr->name);
1983 } else {
1984 ret = LTTCOMM_UST_CHAN_EXIST;
1985 goto error;
1986 }
1987
1988 /* Add channel to all registered applications */
1989 ret = ust_app_add_channel_all(usess, uchan);
1990 if (ret != LTTCOMM_OK) {
1991 goto error;
1992 }
1993
1994 break;
1995 }
1996 case LTTNG_DOMAIN_UST_PID:
1997 {
1998 /*
1999 int sock;
2000 struct ltt_ust_channel *uchan;
2001 struct ltt_ust_session *usess;
2002 struct ust_app *app;
2003
2004 usess = trace_ust_get_session_by_pid(&session->ust_session_list,
2005 domain->attr.pid);
2006 if (usess == NULL) {
2007 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2008 goto error;
2009 }
2010
2011 app = ust_app_get_by_pid(domain->attr.pid);
2012 if (app == NULL) {
2013 ret = LTTCOMM_APP_NOT_FOUND;
2014 goto error;
2015 }
2016 sock = app->sock;
2017
2018 uchan = trace_ust_get_channel_by_name(attr->name, usess);
2019 if (uchan == NULL) {
2020 ret = channel_ust_create(usess, attr, sock);
2021 } else {
2022 ret = channel_ust_enable(usess, uchan, sock);
2023 }
2024
2025 if (ret != LTTCOMM_OK) {
2026 goto error;
2027 }
2028
2029 ret = copy_ust_channel_to_app(usess, attr, app);
2030 if (ret != LTTCOMM_OK) {
2031 goto error;
2032 }
2033
2034 DBG("UST channel %s created for app sock %d with pid %d",
2035 attr->name, app->sock, domain->attr.pid);
2036 */
2037 ret = LTTCOMM_NOT_IMPLEMENTED;
2038 goto error;
2039 }
2040 default:
2041 ret = LTTCOMM_UNKNOWN_DOMAIN;
2042 goto error;
2043 }
2044
2045 ret = LTTCOMM_OK;
2046
2047 error:
2048 return ret;
2049 }
2050
2051 /*
2052 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2053 */
2054 static int cmd_disable_event(struct ltt_session *session, int domain,
2055 char *channel_name, char *event_name)
2056 {
2057 int ret;
2058
2059 switch (domain) {
2060 case LTTNG_DOMAIN_KERNEL:
2061 {
2062 struct ltt_kernel_channel *kchan;
2063
2064 kchan = trace_kernel_get_channel_by_name(channel_name,
2065 session->kernel_session);
2066 if (kchan == NULL) {
2067 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2068 goto error;
2069 }
2070
2071 ret = event_kernel_disable_tracepoint(session->kernel_session, kchan, event_name);
2072 if (ret != LTTCOMM_OK) {
2073 goto error;
2074 }
2075
2076 kernel_wait_quiescent(kernel_tracer_fd);
2077 break;
2078 }
2079 case LTTNG_DOMAIN_UST:
2080 case LTTNG_DOMAIN_UST_EXEC_NAME:
2081 case LTTNG_DOMAIN_UST_PID:
2082 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2083 default:
2084 /* TODO: Other UST domains */
2085 ret = LTTCOMM_NOT_IMPLEMENTED;
2086 goto error;
2087 }
2088
2089 ret = LTTCOMM_OK;
2090
2091 error:
2092 return ret;
2093 }
2094
2095 /*
2096 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2097 */
2098 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2099 char *channel_name)
2100 {
2101 int ret;
2102 struct ltt_kernel_channel *kchan;
2103
2104 switch (domain) {
2105 case LTTNG_DOMAIN_KERNEL:
2106 kchan = trace_kernel_get_channel_by_name(channel_name,
2107 session->kernel_session);
2108 if (kchan == NULL) {
2109 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2110 goto error;
2111 }
2112
2113 ret = event_kernel_disable_all(session->kernel_session, kchan);
2114 if (ret != LTTCOMM_OK) {
2115 goto error;
2116 }
2117
2118 kernel_wait_quiescent(kernel_tracer_fd);
2119 break;
2120 default:
2121 /* TODO: Userspace tracing */
2122 ret = LTTCOMM_NOT_IMPLEMENTED;
2123 goto error;
2124 }
2125
2126 ret = LTTCOMM_OK;
2127
2128 error:
2129 return ret;
2130 }
2131
2132 /*
2133 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2134 */
2135 static int cmd_add_context(struct ltt_session *session, int domain,
2136 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2137 {
2138 int ret;
2139
2140 switch (domain) {
2141 case LTTNG_DOMAIN_KERNEL:
2142 /* Add kernel context to kernel tracer */
2143 ret = context_kernel_add(session->kernel_session, ctx,
2144 event_name, channel_name);
2145 if (ret != LTTCOMM_OK) {
2146 goto error;
2147 }
2148 break;
2149 case LTTNG_DOMAIN_UST:
2150 {
2151 /*
2152 struct ltt_ust_session *usess;
2153
2154 cds_list_for_each_entry(usess, &session->ust_session_list.head, list) {
2155 ret = context_ust_add(usess, ctx,
2156 event_name, channel_name, domain);
2157 if (ret != LTTCOMM_OK) {
2158 goto error;
2159 }
2160 }
2161 break;
2162 */
2163 }
2164 default:
2165 /* TODO: UST other domains */
2166 ret = LTTCOMM_NOT_IMPLEMENTED;
2167 goto error;
2168 }
2169
2170 ret = LTTCOMM_OK;
2171
2172 error:
2173 return ret;
2174 }
2175
2176 /*
2177 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2178 */
2179 static int cmd_enable_event(struct ltt_session *session, int domain,
2180 char *channel_name, struct lttng_event *event)
2181 {
2182 int ret;
2183 struct lttng_channel *attr;
2184 struct ltt_ust_session *usess = session->ust_session;
2185
2186 switch (domain) {
2187 case LTTNG_DOMAIN_KERNEL:
2188 {
2189 struct ltt_kernel_channel *kchan;
2190
2191 kchan = trace_kernel_get_channel_by_name(channel_name,
2192 session->kernel_session);
2193 if (kchan == NULL) {
2194 attr = channel_new_default_attr(domain);
2195 if (attr == NULL) {
2196 ret = LTTCOMM_FATAL;
2197 goto error;
2198 }
2199 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2200
2201 /* This call will notify the kernel thread */
2202 ret = channel_kernel_create(session->kernel_session,
2203 attr, kernel_poll_pipe[1]);
2204 if (ret != LTTCOMM_OK) {
2205 goto error;
2206 }
2207 }
2208
2209 /* Get the newly created kernel channel pointer */
2210 kchan = trace_kernel_get_channel_by_name(channel_name,
2211 session->kernel_session);
2212 if (kchan == NULL) {
2213 /* This sould not happen... */
2214 ret = LTTCOMM_FATAL;
2215 goto error;
2216 }
2217
2218 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2219 event);
2220 if (ret != LTTCOMM_OK) {
2221 goto error;
2222 }
2223
2224 kernel_wait_quiescent(kernel_tracer_fd);
2225 break;
2226 }
2227 case LTTNG_DOMAIN_UST:
2228 {
2229 struct ltt_ust_channel *uchan;
2230 struct ltt_ust_event *uevent;
2231
2232 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2233 channel_name);
2234 if (uchan == NULL) {
2235 /* TODO: Create default channel */
2236 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2237 goto error;
2238 }
2239
2240 uevent = trace_ust_find_event_by_name(uchan->events, event->name);
2241 if (uevent == NULL) {
2242 uevent = trace_ust_create_event(event);
2243 if (uevent == NULL) {
2244 ret = LTTCOMM_FATAL;
2245 goto error;
2246 }
2247 }
2248
2249 ret = ust_app_add_event_all(usess, uchan, uevent);
2250 if (ret < 0) {
2251 ret = LTTCOMM_UST_ENABLE_FAIL;
2252 goto error;
2253 }
2254
2255 rcu_read_lock();
2256 hashtable_add_unique(uchan->events, &uevent->node);
2257 rcu_read_unlock();
2258 break;
2259 }
2260 case LTTNG_DOMAIN_UST_EXEC_NAME:
2261 case LTTNG_DOMAIN_UST_PID:
2262 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2263 default:
2264 ret = LTTCOMM_NOT_IMPLEMENTED;
2265 goto error;
2266 }
2267
2268 ret = LTTCOMM_OK;
2269
2270 error:
2271 return ret;
2272 }
2273
2274 /*
2275 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2276 */
2277 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2278 char *channel_name, int event_type)
2279 {
2280 int ret;
2281 struct ltt_kernel_channel *kchan;
2282
2283 switch (domain) {
2284 case LTTNG_DOMAIN_KERNEL:
2285 kchan = trace_kernel_get_channel_by_name(channel_name,
2286 session->kernel_session);
2287 if (kchan == NULL) {
2288 /* This call will notify the kernel thread */
2289 ret = channel_kernel_create(session->kernel_session, NULL,
2290 kernel_poll_pipe[1]);
2291 if (ret != LTTCOMM_OK) {
2292 goto error;
2293 }
2294 }
2295
2296 /* Get the newly created kernel channel pointer */
2297 kchan = trace_kernel_get_channel_by_name(channel_name,
2298 session->kernel_session);
2299 if (kchan == NULL) {
2300 /* This sould not happen... */
2301 ret = LTTCOMM_FATAL;
2302 goto error;
2303 }
2304
2305 switch (event_type) {
2306 case LTTNG_KERNEL_SYSCALL:
2307 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2308 kchan, kernel_tracer_fd);
2309 break;
2310 case LTTNG_KERNEL_TRACEPOINT:
2311 /*
2312 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2313 * events already registered to the channel.
2314 */
2315 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2316 kchan, kernel_tracer_fd);
2317 break;
2318 case LTTNG_KERNEL_ALL:
2319 /* Enable syscalls and tracepoints */
2320 ret = event_kernel_enable_all(session->kernel_session,
2321 kchan, kernel_tracer_fd);
2322 break;
2323 default:
2324 ret = LTTCOMM_KERN_ENABLE_FAIL;
2325 goto error;
2326 }
2327 if (ret != LTTCOMM_OK) {
2328 goto error;
2329 }
2330
2331 kernel_wait_quiescent(kernel_tracer_fd);
2332 break;
2333 default:
2334 /* TODO: Userspace tracing */
2335 ret = LTTCOMM_NOT_IMPLEMENTED;
2336 goto error;
2337 }
2338
2339 ret = LTTCOMM_OK;
2340
2341 error:
2342 return ret;
2343 }
2344
2345 /*
2346 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2347 */
2348 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2349 {
2350 int ret;
2351 ssize_t nb_events = 0;
2352
2353 switch (domain) {
2354 case LTTNG_DOMAIN_KERNEL:
2355 nb_events = kernel_list_events(kernel_tracer_fd, events);
2356 if (nb_events < 0) {
2357 ret = LTTCOMM_KERN_LIST_FAIL;
2358 goto error;
2359 }
2360 break;
2361 default:
2362 /* TODO: Userspace listing */
2363 ret = LTTCOMM_NOT_IMPLEMENTED;
2364 goto error;
2365 }
2366
2367 return nb_events;
2368
2369 error:
2370 /* Return negative value to differentiate return code */
2371 return -ret;
2372 }
2373
2374 /*
2375 * Command LTTNG_START_TRACE processed by the client thread.
2376 */
2377 static int cmd_start_trace(struct ltt_session *session)
2378 {
2379 int ret;
2380 struct ltt_kernel_session *ksession;
2381 struct ltt_ust_session *usess = session->ust_session;
2382
2383 /* Short cut */
2384 ksession = session->kernel_session;
2385
2386 /* Kernel tracing */
2387 if (ksession != NULL) {
2388 struct ltt_kernel_channel *kchan;
2389
2390 /* Open kernel metadata */
2391 if (ksession->metadata == NULL) {
2392 ret = kernel_open_metadata(ksession, ksession->trace_path);
2393 if (ret < 0) {
2394 ret = LTTCOMM_KERN_META_FAIL;
2395 goto error;
2396 }
2397 }
2398
2399 /* Open kernel metadata stream */
2400 if (ksession->metadata_stream_fd == 0) {
2401 ret = kernel_open_metadata_stream(ksession);
2402 if (ret < 0) {
2403 ERR("Kernel create metadata stream failed");
2404 ret = LTTCOMM_KERN_STREAM_FAIL;
2405 goto error;
2406 }
2407 }
2408
2409 /* For each channel */
2410 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2411 if (kchan->stream_count == 0) {
2412 ret = kernel_open_channel_stream(kchan);
2413 if (ret < 0) {
2414 ret = LTTCOMM_KERN_STREAM_FAIL;
2415 goto error;
2416 }
2417 /* Update the stream global counter */
2418 ksession->stream_count_global += ret;
2419 }
2420 }
2421
2422 /* Setup kernel consumer socket and send fds to it */
2423 ret = init_kernel_tracing(ksession);
2424 if (ret < 0) {
2425 ret = LTTCOMM_KERN_START_FAIL;
2426 goto error;
2427 }
2428
2429 /* This start the kernel tracing */
2430 ret = kernel_start_session(ksession);
2431 if (ret < 0) {
2432 ret = LTTCOMM_KERN_START_FAIL;
2433 goto error;
2434 }
2435
2436 /* Quiescent wait after starting trace */
2437 kernel_wait_quiescent(kernel_tracer_fd);
2438 }
2439
2440 /* Flag session that trace should start automatically */
2441 usess->start_trace = 1;
2442
2443 ret = ust_app_start_trace_all(usess);
2444 if (ret < 0) {
2445 ret = LTTCOMM_UST_START_FAIL;
2446 goto error;
2447 }
2448
2449 ret = LTTCOMM_OK;
2450
2451 error:
2452 return ret;
2453 }
2454
2455 /*
2456 * Command LTTNG_STOP_TRACE processed by the client thread.
2457 */
2458 static int cmd_stop_trace(struct ltt_session *session)
2459 {
2460 int ret;
2461 struct ltt_kernel_channel *kchan;
2462 struct ltt_kernel_session *ksession;
2463 //struct ltt_ust_session *usess;
2464 //struct ltt_ust_channel *ustchan;
2465
2466 /* Short cut */
2467 ksession = session->kernel_session;
2468
2469 /* Kernel tracer */
2470 if (ksession != NULL) {
2471 DBG("Stop kernel tracing");
2472
2473 /* Flush all buffers before stopping */
2474 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2475 if (ret < 0) {
2476 ERR("Kernel metadata flush failed");
2477 }
2478
2479 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2480 ret = kernel_flush_buffer(kchan);
2481 if (ret < 0) {
2482 ERR("Kernel flush buffer error");
2483 }
2484 }
2485
2486 ret = kernel_stop_session(ksession);
2487 if (ret < 0) {
2488 ret = LTTCOMM_KERN_STOP_FAIL;
2489 goto error;
2490 }
2491
2492 kernel_wait_quiescent(kernel_tracer_fd);
2493 }
2494
2495 #ifdef DISABLE
2496 /* Stop each UST session */
2497 DBG("Stop UST tracing");
2498 cds_list_for_each_entry(usess, &session->ust_session_list.head, list) {
2499 /* Flush all buffers before stopping */
2500 ret = ustctl_flush_buffer(usess->sock, usess->metadata->obj);
2501 if (ret < 0) {
2502 ERR("UST metadata flush failed");
2503 }
2504
2505 cds_list_for_each_entry(ustchan, &usess->channels.head, list) {
2506 ret = ustctl_flush_buffer(usess->sock, ustchan->obj);
2507 if (ret < 0) {
2508 ERR("UST flush buffer error");
2509 }
2510 }
2511
2512 ret = ustctl_stop_session(usess->sock, usess->handle);
2513 if (ret < 0) {
2514 ret = LTTCOMM_KERN_STOP_FAIL;
2515 goto error;
2516 }
2517
2518 ustctl_wait_quiescent(usess->sock);
2519 }
2520 #endif
2521
2522 ret = LTTCOMM_OK;
2523
2524 error:
2525 return ret;
2526 }
2527
2528 /*
2529 * Command LTTNG_CREATE_SESSION processed by the client thread.
2530 */
2531 static int cmd_create_session(char *name, char *path)
2532 {
2533 int ret;
2534
2535 ret = session_create(name, path);
2536 if (ret != LTTCOMM_OK) {
2537 goto error;
2538 }
2539
2540 ret = LTTCOMM_OK;
2541
2542 error:
2543 return ret;
2544 }
2545
2546 /*
2547 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2548 */
2549 static int cmd_destroy_session(struct ltt_session *session, char *name)
2550 {
2551 int ret;
2552
2553 /* Clean kernel session teardown */
2554 teardown_kernel_session(session);
2555
2556 /*
2557 * Must notify the kernel thread here to update it's poll setin order
2558 * to remove the channel(s)' fd just destroyed.
2559 */
2560 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2561 if (ret < 0) {
2562 perror("write kernel poll pipe");
2563 }
2564
2565 ret = session_destroy(session);
2566
2567 return ret;
2568 }
2569
2570 /*
2571 * Command LTTNG_CALIBRATE processed by the client thread.
2572 */
2573 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2574 {
2575 int ret;
2576
2577 switch (domain) {
2578 case LTTNG_DOMAIN_KERNEL:
2579 {
2580 struct lttng_kernel_calibrate kcalibrate;
2581
2582 kcalibrate.type = calibrate->type;
2583 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2584 if (ret < 0) {
2585 ret = LTTCOMM_KERN_ENABLE_FAIL;
2586 goto error;
2587 }
2588 break;
2589 }
2590 default:
2591 /* TODO: Userspace tracing */
2592 ret = LTTCOMM_NOT_IMPLEMENTED;
2593 goto error;
2594 }
2595
2596 ret = LTTCOMM_OK;
2597
2598 error:
2599 return ret;
2600 }
2601
2602 /*
2603 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2604 */
2605 static int cmd_register_consumer(struct ltt_session *session, int domain,
2606 char *sock_path)
2607 {
2608 int ret, sock;
2609
2610 switch (domain) {
2611 case LTTNG_DOMAIN_KERNEL:
2612 /* Can't register a consumer if there is already one */
2613 if (session->kernel_session->consumer_fd != 0) {
2614 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2615 goto error;
2616 }
2617
2618 sock = lttcomm_connect_unix_sock(sock_path);
2619 if (sock < 0) {
2620 ret = LTTCOMM_CONNECT_FAIL;
2621 goto error;
2622 }
2623
2624 session->kernel_session->consumer_fd = sock;
2625 break;
2626 default:
2627 /* TODO: Userspace tracing */
2628 ret = LTTCOMM_NOT_IMPLEMENTED;
2629 goto error;
2630 }
2631
2632 ret = LTTCOMM_OK;
2633
2634 error:
2635 return ret;
2636 }
2637
2638 /*
2639 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2640 */
2641 static ssize_t cmd_list_domains(struct ltt_session *session,
2642 struct lttng_domain **domains)
2643 {
2644 int ret;
2645 ssize_t nb_dom = 0;
2646
2647 if (session->kernel_session != NULL) {
2648 nb_dom++;
2649 }
2650
2651 /* TODO: User-space tracer domain support */
2652
2653 *domains = malloc(nb_dom * sizeof(struct lttng_domain));
2654 if (*domains == NULL) {
2655 ret = -LTTCOMM_FATAL;
2656 goto error;
2657 }
2658
2659 (*domains)[0].type = LTTNG_DOMAIN_KERNEL;
2660
2661 return nb_dom;
2662
2663 error:
2664 return ret;
2665 }
2666
2667 /*
2668 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2669 */
2670 static ssize_t cmd_list_channels(struct ltt_session *session,
2671 struct lttng_channel **channels)
2672 {
2673 int ret;
2674 ssize_t nb_chan = 0;
2675
2676 if (session->kernel_session != NULL) {
2677 nb_chan += session->kernel_session->channel_count;
2678 }
2679
2680 *channels = malloc(nb_chan * sizeof(struct lttng_channel));
2681 if (*channels == NULL) {
2682 ret = -LTTCOMM_FATAL;
2683 goto error;
2684 }
2685
2686 list_lttng_channels(session, *channels);
2687
2688 /* TODO UST support */
2689
2690 return nb_chan;
2691
2692 error:
2693 return ret;
2694 }
2695
2696 /*
2697 * Command LTTNG_LIST_EVENTS processed by the client thread.
2698 */
2699 static ssize_t cmd_list_events(struct ltt_session *session,
2700 char *channel_name, struct lttng_event **events)
2701 {
2702 int ret;
2703 ssize_t nb_event = 0;
2704 struct ltt_kernel_channel *kchan = NULL;
2705
2706 if (session->kernel_session != NULL) {
2707 kchan = trace_kernel_get_channel_by_name(channel_name,
2708 session->kernel_session);
2709 if (kchan == NULL) {
2710 ret = -LTTCOMM_KERN_CHAN_NOT_FOUND;
2711 goto error;
2712 }
2713 nb_event += kchan->event_count;
2714 }
2715
2716 *events = malloc(nb_event * sizeof(struct lttng_event));
2717 if (*events == NULL) {
2718 ret = -LTTCOMM_FATAL;
2719 goto error;
2720 }
2721
2722 list_lttng_events(kchan, *events);
2723
2724 /* TODO: User-space tracer support */
2725
2726 return nb_event;
2727
2728 error:
2729 return ret;
2730 }
2731
2732 /*
2733 * Process the command requested by the lttng client within the command
2734 * context structure. This function make sure that the return structure (llm)
2735 * is set and ready for transmission before returning.
2736 *
2737 * Return any error encountered or 0 for success.
2738 */
2739 static int process_client_msg(struct command_ctx *cmd_ctx)
2740 {
2741 int ret = LTTCOMM_OK;
2742 int need_tracing_session = 1;
2743
2744 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
2745
2746 /*
2747 * Check for command that don't needs to allocate a returned payload. We do
2748 * this here so we don't have to make the call for no payload at each
2749 * command.
2750 */
2751 switch(cmd_ctx->lsm->cmd_type) {
2752 case LTTNG_LIST_SESSIONS:
2753 case LTTNG_LIST_TRACEPOINTS:
2754 case LTTNG_LIST_DOMAINS:
2755 case LTTNG_LIST_CHANNELS:
2756 case LTTNG_LIST_EVENTS:
2757 break;
2758 default:
2759 /* Setup lttng message with no payload */
2760 ret = setup_lttng_msg(cmd_ctx, 0);
2761 if (ret < 0) {
2762 /* This label does not try to unlock the session */
2763 goto init_setup_error;
2764 }
2765 }
2766
2767 /* Commands that DO NOT need a session. */
2768 switch (cmd_ctx->lsm->cmd_type) {
2769 case LTTNG_CALIBRATE:
2770 case LTTNG_CREATE_SESSION:
2771 case LTTNG_LIST_SESSIONS:
2772 case LTTNG_LIST_TRACEPOINTS:
2773 need_tracing_session = 0;
2774 break;
2775 default:
2776 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
2777 session_lock_list();
2778 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
2779 session_unlock_list();
2780 if (cmd_ctx->session == NULL) {
2781 if (cmd_ctx->lsm->session.name != NULL) {
2782 ret = LTTCOMM_SESS_NOT_FOUND;
2783 } else {
2784 /* If no session name specified */
2785 ret = LTTCOMM_SELECT_SESS;
2786 }
2787 goto error;
2788 } else {
2789 /* Acquire lock for the session */
2790 session_lock(cmd_ctx->session);
2791 }
2792 break;
2793 }
2794
2795 /*
2796 * Check domain type for specific "pre-action".
2797 */
2798 switch (cmd_ctx->lsm->domain.type) {
2799 case LTTNG_DOMAIN_KERNEL:
2800 /* Kernel tracer check */
2801 if (kernel_tracer_fd == 0) {
2802 /* Basically, load kernel tracer modules */
2803 init_kernel_tracer();
2804 if (kernel_tracer_fd == 0) {
2805 ret = LTTCOMM_KERN_NA;
2806 goto error;
2807 }
2808 }
2809
2810 /* Need a session for kernel command */
2811 if (need_tracing_session) {
2812 if (cmd_ctx->session->kernel_session == NULL) {
2813 ret = create_kernel_session(cmd_ctx->session);
2814 if (ret < 0) {
2815 ret = LTTCOMM_KERN_SESS_FAIL;
2816 goto error;
2817 }
2818 }
2819
2820 /* Start the kernel consumer daemon */
2821 pthread_mutex_lock(&kconsumer_data.pid_mutex);
2822 if (kconsumer_data.pid == 0 &&
2823 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
2824 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2825 ret = start_consumerd(&kconsumer_data);
2826 if (ret < 0) {
2827 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2828 goto error;
2829 }
2830 }
2831 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2832 }
2833 break;
2834 case LTTNG_DOMAIN_UST:
2835 {
2836 if (need_tracing_session) {
2837 if (cmd_ctx->session->ust_session == NULL) {
2838 ret = create_ust_session(cmd_ctx->session,
2839 &cmd_ctx->lsm->domain);
2840 if (ret != LTTCOMM_OK) {
2841 goto error;
2842 }
2843 }
2844 /* Start the kernel consumer daemon */
2845 pthread_mutex_lock(&ustconsumer_data.pid_mutex);
2846 if (ustconsumer_data.pid == 0 &&
2847 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
2848 pthread_mutex_unlock(&ustconsumer_data.pid_mutex);
2849 ret = start_consumerd(&ustconsumer_data);
2850 if (ret < 0) {
2851 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2852 goto error;
2853 }
2854
2855 cmd_ctx->session->ust_session->consumer_fd =
2856 ustconsumer_data.cmd_sock;
2857 }
2858 pthread_mutex_unlock(&ustconsumer_data.pid_mutex);
2859 }
2860 break;
2861 }
2862 default:
2863 break;
2864 }
2865
2866 /* Process by command type */
2867 switch (cmd_ctx->lsm->cmd_type) {
2868 case LTTNG_ADD_CONTEXT:
2869 {
2870 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2871 cmd_ctx->lsm->u.context.channel_name,
2872 cmd_ctx->lsm->u.context.event_name,
2873 &cmd_ctx->lsm->u.context.ctx);
2874 break;
2875 }
2876 case LTTNG_DISABLE_CHANNEL:
2877 {
2878 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2879 cmd_ctx->lsm->u.disable.channel_name);
2880 break;
2881 }
2882 case LTTNG_DISABLE_EVENT:
2883 {
2884 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2885 cmd_ctx->lsm->u.disable.channel_name,
2886 cmd_ctx->lsm->u.disable.name);
2887 ret = LTTCOMM_OK;
2888 break;
2889 }
2890 case LTTNG_DISABLE_ALL_EVENT:
2891 {
2892 DBG("Disabling all events");
2893
2894 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2895 cmd_ctx->lsm->u.disable.channel_name);
2896 break;
2897 }
2898 case LTTNG_ENABLE_CHANNEL:
2899 {
2900 ret = cmd_enable_channel(cmd_ctx->session, &cmd_ctx->lsm->domain,
2901 &cmd_ctx->lsm->u.channel.chan);
2902 break;
2903 }
2904 case LTTNG_ENABLE_EVENT:
2905 {
2906 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2907 cmd_ctx->lsm->u.enable.channel_name,
2908 &cmd_ctx->lsm->u.enable.event);
2909 break;
2910 }
2911 case LTTNG_ENABLE_ALL_EVENT:
2912 {
2913 DBG("Enabling all events");
2914
2915 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2916 cmd_ctx->lsm->u.enable.channel_name,
2917 cmd_ctx->lsm->u.enable.event.type);
2918 break;
2919 }
2920 case LTTNG_LIST_TRACEPOINTS:
2921 {
2922 struct lttng_event *events;
2923 ssize_t nb_events;
2924
2925 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
2926 if (nb_events < 0) {
2927 ret = -nb_events;
2928 goto error;
2929 }
2930
2931 /*
2932 * Setup lttng message with payload size set to the event list size in
2933 * bytes and then copy list into the llm payload.
2934 */
2935 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
2936 if (ret < 0) {
2937 free(events);
2938 goto setup_error;
2939 }
2940
2941 /* Copy event list into message payload */
2942 memcpy(cmd_ctx->llm->payload, events,
2943 sizeof(struct lttng_event) * nb_events);
2944
2945 free(events);
2946
2947 ret = LTTCOMM_OK;
2948 break;
2949 }
2950 case LTTNG_START_TRACE:
2951 {
2952 ret = cmd_start_trace(cmd_ctx->session);
2953 break;
2954 }
2955 case LTTNG_STOP_TRACE:
2956 {
2957 ret = cmd_stop_trace(cmd_ctx->session);
2958 break;
2959 }
2960 case LTTNG_CREATE_SESSION:
2961 {
2962 ret = cmd_create_session(cmd_ctx->lsm->session.name,
2963 cmd_ctx->lsm->session.path);
2964 break;
2965 }
2966 case LTTNG_DESTROY_SESSION:
2967 {
2968 ret = cmd_destroy_session(cmd_ctx->session,
2969 cmd_ctx->lsm->session.name);
2970 break;
2971 }
2972 case LTTNG_LIST_DOMAINS:
2973 {
2974 ssize_t nb_dom;
2975 struct lttng_domain *domains;
2976
2977 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
2978 if (nb_dom < 0) {
2979 ret = -nb_dom;
2980 goto error;
2981 }
2982
2983 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
2984 if (ret < 0) {
2985 goto setup_error;
2986 }
2987
2988 /* Copy event list into message payload */
2989 memcpy(cmd_ctx->llm->payload, domains,
2990 nb_dom * sizeof(struct lttng_domain));
2991
2992 free(domains);
2993
2994 ret = LTTCOMM_OK;
2995 break;
2996 }
2997 case LTTNG_LIST_CHANNELS:
2998 {
2999 size_t nb_chan;
3000 struct lttng_channel *channels;
3001
3002 nb_chan = cmd_list_channels(cmd_ctx->session, &channels);
3003 if (nb_chan < 0) {
3004 ret = -nb_chan;
3005 goto error;
3006 }
3007
3008 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3009 if (ret < 0) {
3010 goto setup_error;
3011 }
3012
3013 /* Copy event list into message payload */
3014 memcpy(cmd_ctx->llm->payload, channels,
3015 nb_chan * sizeof(struct lttng_channel));
3016
3017 free(channels);
3018
3019 ret = LTTCOMM_OK;
3020 break;
3021 }
3022 case LTTNG_LIST_EVENTS:
3023 {
3024 size_t nb_event;
3025 struct lttng_event *events = NULL;
3026
3027 nb_event = cmd_list_events(cmd_ctx->session,
3028 cmd_ctx->lsm->u.list.channel_name, &events);
3029 if (nb_event < 0) {
3030 ret = -nb_event;
3031 goto error;
3032 }
3033
3034 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3035 if (ret < 0) {
3036 goto setup_error;
3037 }
3038
3039 /* Copy event list into message payload */
3040 memcpy(cmd_ctx->llm->payload, events,
3041 nb_event * sizeof(struct lttng_event));
3042
3043 free(events);
3044
3045 ret = LTTCOMM_OK;
3046 break;
3047 }
3048 case LTTNG_LIST_SESSIONS:
3049 {
3050 session_lock_list();
3051
3052 if (session_list_ptr->count == 0) {
3053 ret = LTTCOMM_NO_SESSION;
3054 session_unlock_list();
3055 goto error;
3056 }
3057
3058 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) *
3059 session_list_ptr->count);
3060 if (ret < 0) {
3061 session_unlock_list();
3062 goto setup_error;
3063 }
3064
3065 /* Filled the session array */
3066 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
3067
3068 session_unlock_list();
3069
3070 ret = LTTCOMM_OK;
3071 break;
3072 }
3073 case LTTNG_CALIBRATE:
3074 {
3075 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3076 &cmd_ctx->lsm->u.calibrate);
3077 break;
3078 }
3079 case LTTNG_REGISTER_CONSUMER:
3080 {
3081 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3082 cmd_ctx->lsm->u.reg.path);
3083 break;
3084 }
3085 default:
3086 ret = LTTCOMM_UND;
3087 break;
3088 }
3089
3090 error:
3091 if (cmd_ctx->llm == NULL) {
3092 DBG("Missing llm structure. Allocating one.");
3093 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3094 goto setup_error;
3095 }
3096 }
3097 /* Set return code */
3098 cmd_ctx->llm->ret_code = ret;
3099 setup_error:
3100 if (cmd_ctx->session) {
3101 session_unlock(cmd_ctx->session);
3102 }
3103 init_setup_error:
3104 return ret;
3105 }
3106
3107 /*
3108 * This thread manage all clients request using the unix client socket for
3109 * communication.
3110 */
3111 static void *thread_manage_clients(void *data)
3112 {
3113 int sock = 0, ret, i, pollfd;
3114 uint32_t revents, nb_fd;
3115 struct command_ctx *cmd_ctx = NULL;
3116 struct lttng_poll_event events;
3117
3118 DBG("[thread] Manage client started");
3119
3120 rcu_register_thread();
3121
3122 ret = lttcomm_listen_unix_sock(client_sock);
3123 if (ret < 0) {
3124 goto error;
3125 }
3126
3127 /*
3128 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3129 * more will be added to this poll set.
3130 */
3131 ret = create_thread_poll_set(&events, 2);
3132 if (ret < 0) {
3133 goto error;
3134 }
3135
3136 /* Add the application registration socket */
3137 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3138 if (ret < 0) {
3139 goto error;
3140 }
3141
3142 /*
3143 * Notify parent pid that we are ready to accept command for client side.
3144 */
3145 if (opt_sig_parent) {
3146 kill(ppid, SIGCHLD);
3147 }
3148
3149 while (1) {
3150 DBG("Accepting client command ...");
3151
3152 nb_fd = LTTNG_POLL_GETNB(&events);
3153
3154 /* Inifinite blocking call, waiting for transmission */
3155 ret = lttng_poll_wait(&events, -1);
3156 if (ret < 0) {
3157 goto error;
3158 }
3159
3160 for (i = 0; i < nb_fd; i++) {
3161 /* Fetch once the poll data */
3162 revents = LTTNG_POLL_GETEV(&events, i);
3163 pollfd = LTTNG_POLL_GETFD(&events, i);
3164
3165 /* Thread quit pipe has been closed. Killing thread. */
3166 ret = check_thread_quit_pipe(pollfd, revents);
3167 if (ret) {
3168 goto error;
3169 }
3170
3171 /* Event on the registration socket */
3172 if (pollfd == client_sock) {
3173 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3174 ERR("Client socket poll error");
3175 goto error;
3176 }
3177 }
3178 }
3179
3180 DBG("Wait for client response");
3181
3182 sock = lttcomm_accept_unix_sock(client_sock);
3183 if (sock < 0) {
3184 goto error;
3185 }
3186
3187 /* Allocate context command to process the client request */
3188 cmd_ctx = malloc(sizeof(struct command_ctx));
3189 if (cmd_ctx == NULL) {
3190 perror("malloc cmd_ctx");
3191 goto error;
3192 }
3193
3194 /* Allocate data buffer for reception */
3195 cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
3196 if (cmd_ctx->lsm == NULL) {
3197 perror("malloc cmd_ctx->lsm");
3198 goto error;
3199 }
3200
3201 cmd_ctx->llm = NULL;
3202 cmd_ctx->session = NULL;
3203
3204 /*
3205 * Data is received from the lttng client. The struct
3206 * lttcomm_session_msg (lsm) contains the command and data request of
3207 * the client.
3208 */
3209 DBG("Receiving data from client ...");
3210 ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm,
3211 sizeof(struct lttcomm_session_msg));
3212 if (ret <= 0) {
3213 DBG("Nothing recv() from client... continuing");
3214 close(sock);
3215 free(cmd_ctx);
3216 continue;
3217 }
3218
3219 // TODO: Validate cmd_ctx including sanity check for
3220 // security purpose.
3221
3222 rcu_thread_online();
3223 /*
3224 * This function dispatch the work to the kernel or userspace tracer
3225 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3226 * informations for the client. The command context struct contains
3227 * everything this function may needs.
3228 */
3229 ret = process_client_msg(cmd_ctx);
3230 rcu_thread_offline();
3231 if (ret < 0) {
3232 /*
3233 * TODO: Inform client somehow of the fatal error. At
3234 * this point, ret < 0 means that a malloc failed
3235 * (ENOMEM). Error detected but still accept command.
3236 */
3237 clean_command_ctx(&cmd_ctx);
3238 continue;
3239 }
3240
3241 DBG("Sending response (size: %d, retcode: %s)",
3242 cmd_ctx->lttng_msg_size,
3243 lttng_strerror(-cmd_ctx->llm->ret_code));
3244 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3245 if (ret < 0) {
3246 ERR("Failed to send data back to client");
3247 }
3248
3249 clean_command_ctx(&cmd_ctx);
3250
3251 /* End of transmission */
3252 close(sock);
3253 }
3254
3255 error:
3256 DBG("Client thread dying");
3257 unlink(client_unix_sock_path);
3258 close(client_sock);
3259 close(sock);
3260
3261 lttng_poll_clean(&events);
3262 clean_command_ctx(&cmd_ctx);
3263
3264 rcu_unregister_thread();
3265 return NULL;
3266 }
3267
3268
3269 /*
3270 * usage function on stderr
3271 */
3272 static void usage(void)
3273 {
3274 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3275 fprintf(stderr, " -h, --help Display this usage.\n");
3276 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3277 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3278 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3279 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3280 fprintf(stderr, " --ustconsumerd-err-sock PATH Specify path for the UST consumer error socket\n");
3281 fprintf(stderr, " --ustconsumerd-cmd-sock PATH Specify path for the UST consumer command socket\n");
3282 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3283 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3284 fprintf(stderr, " -V, --version Show version number.\n");
3285 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3286 fprintf(stderr, " -q, --quiet No output at all.\n");
3287 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3288 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3289 }
3290
3291 /*
3292 * daemon argument parsing
3293 */
3294 static int parse_args(int argc, char **argv)
3295 {
3296 int c;
3297
3298 static struct option long_options[] = {
3299 { "client-sock", 1, 0, 'c' },
3300 { "apps-sock", 1, 0, 'a' },
3301 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3302 { "kconsumerd-err-sock", 1, 0, 'E' },
3303 { "ustconsumerd-cmd-sock", 1, 0, 'D' },
3304 { "ustconsumerd-err-sock", 1, 0, 'F' },
3305 { "daemonize", 0, 0, 'd' },
3306 { "sig-parent", 0, 0, 'S' },
3307 { "help", 0, 0, 'h' },
3308 { "group", 1, 0, 'g' },
3309 { "version", 0, 0, 'V' },
3310 { "quiet", 0, 0, 'q' },
3311 { "verbose", 0, 0, 'v' },
3312 { "verbose-consumer", 0, 0, 'Z' },
3313 { NULL, 0, 0, 0 }
3314 };
3315
3316 while (1) {
3317 int option_index = 0;
3318 c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:C:E:D:F:Z",
3319 long_options, &option_index);
3320 if (c == -1) {
3321 break;
3322 }
3323
3324 switch (c) {
3325 case 0:
3326 fprintf(stderr, "option %s", long_options[option_index].name);
3327 if (optarg) {
3328 fprintf(stderr, " with arg %s\n", optarg);
3329 }
3330 break;
3331 case 'c':
3332 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3333 break;
3334 case 'a':
3335 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3336 break;
3337 case 'd':
3338 opt_daemon = 1;
3339 break;
3340 case 'g':
3341 opt_tracing_group = strdup(optarg);
3342 break;
3343 case 'h':
3344 usage();