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