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c288afbb049f4a078f049756fce9c20094f1d705
[lttng-tools.git] / ltt-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 #ifdef CONFIG_LTTNG_TOOLS_HAVE_UST
46 #include <ust/lttng-ust-ctl.h>
47 #else
48 #include "lttng-ust-ctl.h"
49 #endif
50
51
52 #include <lttngerr.h>
53
54 #include "channel.h"
55 #include "compat/poll.h"
56 #include "context.h"
57 #include "event.h"
58 #include "futex.h"
59 #include "kernel-ctl.h"
60 #include "ltt-sessiond.h"
61 #include "shm.h"
62 #include "ust-app.h"
63 #include "ust-ctl.h"
64 #include "utils.h"
65 #include "ust-ctl.h"
66
67 struct consumer_data {
68 enum lttng_consumer_type type;
69
70 pthread_t thread; /* Worker thread interacting with the consumer */
71 sem_t sem;
72
73 /* Mutex to control consumerd pid assignation */
74 pthread_mutex_t pid_mutex;
75 pid_t pid;
76
77 int err_sock;
78 int cmd_sock;
79
80 /* consumer error and command Unix socket path */
81 char err_unix_sock_path[PATH_MAX];
82 char cmd_unix_sock_path[PATH_MAX];
83 };
84
85 /* Const values */
86 const char default_home_dir[] = DEFAULT_HOME_DIR;
87 const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
88 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
89 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
90
91 /* Variables */
92 int opt_verbose; /* Not static for lttngerr.h */
93 int opt_verbose_consumer; /* Not static for lttngerr.h */
94 int opt_quiet; /* Not static for lttngerr.h */
95
96 const char *progname;
97 const char *opt_tracing_group;
98 static int opt_sig_parent;
99 static int opt_daemon;
100 static int is_root; /* Set to 1 if the daemon is running as root */
101 static pid_t ppid; /* Parent PID for --sig-parent option */
102
103 /* Consumer daemon specific control data */
104 static struct consumer_data kconsumer_data = {
105 .type = LTTNG_CONSUMER_KERNEL,
106 };
107 static struct consumer_data ustconsumer_data = {
108 .type = LTTNG_CONSUMER_UST,
109 };
110
111 static int dispatch_thread_exit;
112
113 /* Global application Unix socket path */
114 static char apps_unix_sock_path[PATH_MAX];
115 /* Global client Unix socket path */
116 static char client_unix_sock_path[PATH_MAX];
117 /* global wait shm path for UST */
118 static char wait_shm_path[PATH_MAX];
119
120 /* Sockets and FDs */
121 static int client_sock;
122 static int apps_sock;
123 static int kernel_tracer_fd;
124 static int kernel_poll_pipe[2];
125
126 /*
127 * Quit pipe for all threads. This permits a single cancellation point
128 * for all threads when receiving an event on the pipe.
129 */
130 static int thread_quit_pipe[2];
131
132 /*
133 * This pipe is used to inform the thread managing application communication
134 * that a command is queued and ready to be processed.
135 */
136 static int apps_cmd_pipe[2];
137
138 /* Pthread, Mutexes and Semaphores */
139 static pthread_t apps_thread;
140 static pthread_t reg_apps_thread;
141 static pthread_t client_thread;
142 static pthread_t kernel_thread;
143 static pthread_t dispatch_thread;
144
145
146 /*
147 * UST registration command queue. This queue is tied with a futex and uses a N
148 * wakers / 1 waiter implemented and detailed in futex.c/.h
149 *
150 * The thread_manage_apps and thread_dispatch_ust_registration interact with
151 * this queue and the wait/wake scheme.
152 */
153 static struct ust_cmd_queue ust_cmd_queue;
154
155 /*
156 * Pointer initialized before thread creation.
157 *
158 * This points to the tracing session list containing the session count and a
159 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
160 * MUST NOT be taken if you call a public function in session.c.
161 *
162 * The lock is nested inside the structure: session_list_ptr->lock. Please use
163 * session_lock_list and session_unlock_list for lock acquisition.
164 */
165 static struct ltt_session_list *session_list_ptr;
166
167 /*
168 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
169 */
170 static int create_thread_poll_set(struct lttng_poll_event *events,
171 unsigned int size)
172 {
173 int ret;
174
175 if (events == NULL || size == 0) {
176 ret = -1;
177 goto error;
178 }
179
180 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
181 if (ret < 0) {
182 goto error;
183 }
184
185 /* Add quit pipe */
186 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
187 if (ret < 0) {
188 goto error;
189 }
190
191 return 0;
192
193 error:
194 return ret;
195 }
196
197 /*
198 * Check if the thread quit pipe was triggered.
199 *
200 * Return 1 if it was triggered else 0;
201 */
202 static int check_thread_quit_pipe(int fd, uint32_t events)
203 {
204 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
205 return 1;
206 }
207
208 return 0;
209 }
210
211 /*
212 * Remove modules in reverse load order.
213 */
214 static int modprobe_remove_kernel_modules(void)
215 {
216 int ret = 0, i;
217 char modprobe[256];
218
219 for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
220 ret = snprintf(modprobe, sizeof(modprobe),
221 "/sbin/modprobe --remove --quiet %s",
222 kernel_modules_list[i].name);
223 if (ret < 0) {
224 perror("snprintf modprobe --remove");
225 goto error;
226 }
227 modprobe[sizeof(modprobe) - 1] = '\0';
228 ret = system(modprobe);
229 if (ret == -1) {
230 ERR("Unable to launch modprobe --remove for module %s",
231 kernel_modules_list[i].name);
232 } else if (kernel_modules_list[i].required
233 && WEXITSTATUS(ret) != 0) {
234 ERR("Unable to remove module %s",
235 kernel_modules_list[i].name);
236 } else {
237 DBG("Modprobe removal successful %s",
238 kernel_modules_list[i].name);
239 }
240 }
241
242 error:
243 return ret;
244 }
245
246 /*
247 * Return group ID of the tracing group or -1 if not found.
248 */
249 static gid_t allowed_group(void)
250 {
251 struct group *grp;
252
253 if (opt_tracing_group) {
254 grp = getgrnam(opt_tracing_group);
255 } else {
256 grp = getgrnam(default_tracing_group);
257 }
258 if (!grp) {
259 return -1;
260 } else {
261 return grp->gr_gid;
262 }
263 }
264
265 /*
266 * Init thread quit pipe.
267 *
268 * Return -1 on error or 0 if all pipes are created.
269 */
270 static int init_thread_quit_pipe(void)
271 {
272 int ret;
273
274 ret = pipe2(thread_quit_pipe, O_CLOEXEC);
275 if (ret < 0) {
276 perror("thread quit pipe");
277 goto error;
278 }
279
280 error:
281 return ret;
282 }
283
284 /*
285 * Complete teardown of a kernel session. This free all data structure related
286 * to a kernel session and update counter.
287 */
288 static void teardown_kernel_session(struct ltt_session *session)
289 {
290 if (session->kernel_session != NULL) {
291 DBG("Tearing down kernel session");
292
293 /*
294 * If a custom kernel consumer was registered, close the socket before
295 * tearing down the complete kernel session structure
296 */
297 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
298 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
299 }
300
301 trace_kernel_destroy_session(session->kernel_session);
302 /* Extra precaution */
303 session->kernel_session = NULL;
304 }
305 }
306
307 /*
308 * Stop all threads by closing the thread quit pipe.
309 */
310 static void stop_threads(void)
311 {
312 int ret;
313
314 /* Stopping all threads */
315 DBG("Terminating all threads");
316 ret = notify_thread_pipe(thread_quit_pipe[1]);
317 if (ret < 0) {
318 ERR("write error on thread quit pipe");
319 }
320
321 /* Dispatch thread */
322 dispatch_thread_exit = 1;
323 futex_nto1_wake(&ust_cmd_queue.futex);
324 }
325
326 /*
327 * Cleanup the daemon
328 */
329 static void cleanup(void)
330 {
331 int ret;
332 char *cmd;
333 struct ltt_session *sess, *stmp;
334
335 DBG("Cleaning up");
336
337 /* <fun> */
338 MSG("%c[%d;%dm*** assert failed *** ==> %c[%dm%c[%d;%dm"
339 "Matthew, BEET driven development works!%c[%dm",
340 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
341 /* </fun> */
342
343 if (is_root) {
344 DBG("Removing %s directory", LTTNG_RUNDIR);
345 ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
346 if (ret < 0) {
347 ERR("asprintf failed. Something is really wrong!");
348 }
349
350 /* Remove lttng run directory */
351 ret = system(cmd);
352 if (ret < 0) {
353 ERR("Unable to clean " LTTNG_RUNDIR);
354 }
355 }
356
357 DBG("Cleaning up all session");
358
359 /* Destroy session list mutex */
360 if (session_list_ptr != NULL) {
361 pthread_mutex_destroy(&session_list_ptr->lock);
362
363 /* Cleanup ALL session */
364 cds_list_for_each_entry_safe(sess, stmp,
365 &session_list_ptr->head, list) {
366 teardown_kernel_session(sess);
367 // TODO complete session cleanup (including UST)
368 }
369 }
370
371 DBG("Closing all UST sockets");
372 ust_app_clean_list();
373
374 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
375
376 DBG("Closing kernel fd");
377 close(kernel_tracer_fd);
378
379 if (is_root) {
380 DBG("Unloading kernel modules");
381 modprobe_remove_kernel_modules();
382 }
383
384 close(thread_quit_pipe[0]);
385 close(thread_quit_pipe[1]);
386 }
387
388 /*
389 * Send data on a unix socket using the liblttsessiondcomm API.
390 *
391 * Return lttcomm error code.
392 */
393 static int send_unix_sock(int sock, void *buf, size_t len)
394 {
395 /* Check valid length */
396 if (len <= 0) {
397 return -1;
398 }
399
400 return lttcomm_send_unix_sock(sock, buf, len);
401 }
402
403 /*
404 * Free memory of a command context structure.
405 */
406 static void clean_command_ctx(struct command_ctx **cmd_ctx)
407 {
408 DBG("Clean command context structure");
409 if (*cmd_ctx) {
410 if ((*cmd_ctx)->llm) {
411 free((*cmd_ctx)->llm);
412 }
413 if ((*cmd_ctx)->lsm) {
414 free((*cmd_ctx)->lsm);
415 }
416 free(*cmd_ctx);
417 *cmd_ctx = NULL;
418 }
419 }
420
421 /*
422 * Send all stream fds of kernel channel to the consumer.
423 */
424 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
425 int sock, struct ltt_kernel_channel *channel)
426 {
427 int ret;
428 struct ltt_kernel_stream *stream;
429 struct lttcomm_consumer_msg lkm;
430
431 DBG("Sending streams of channel %s to kernel consumer",
432 channel->channel->name);
433
434 /* Send channel */
435 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
436 lkm.u.channel.channel_key = channel->fd;
437 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
438 lkm.u.channel.mmap_len = 0; /* for kernel */
439 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
440 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
441 if (ret < 0) {
442 perror("send consumer channel");
443 goto error;
444 }
445
446 /* Send streams */
447 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
448 if (!stream->fd) {
449 continue;
450 }
451 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
452 lkm.u.stream.channel_key = channel->fd;
453 lkm.u.stream.stream_key = stream->fd;
454 lkm.u.stream.state = stream->state;
455 lkm.u.stream.output = channel->channel->attr.output;
456 lkm.u.stream.mmap_len = 0; /* for kernel */
457 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
458 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
459 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
460 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
461 if (ret < 0) {
462 perror("send consumer stream");
463 goto error;
464 }
465 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
466 if (ret < 0) {
467 perror("send consumer stream ancillary data");
468 goto error;
469 }
470 }
471
472 DBG("consumer channel streams sent");
473
474 return 0;
475
476 error:
477 return ret;
478 }
479
480 /*
481 * Send all stream fds of UST channel to the consumer.
482 */
483 static int send_ustconsumer_channel_streams(struct consumer_data *consumer_data,
484 int sock, struct ltt_ust_channel *channel)
485 {
486 int ret, fds[2];
487 struct ltt_ust_stream *stream;
488 struct lttcomm_consumer_msg lum;
489
490 DBG("Sending streams of channel %s to UST consumer",
491 channel->name);
492
493 /* Send channel */
494 lum.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
495 /*
496 * We need to keep shm_fd open to make sure this key stays
497 * unique within the session daemon.
498 */
499 lum.u.channel.channel_key = channel->obj->shm_fd;
500 lum.u.channel.max_sb_size = channel->attr.subbuf_size;
501 lum.u.channel.mmap_len = channel->obj->memory_map_size;
502 DBG("Sending channel %d to consumer", lum.u.channel.channel_key);
503 ret = lttcomm_send_unix_sock(sock, &lum, sizeof(lum));
504 if (ret < 0) {
505 perror("send consumer channel");
506 goto error;
507 }
508 fds[0] = channel->obj->shm_fd;
509 fds[1] = channel->obj->wait_fd;
510 ret = lttcomm_send_fds_unix_sock(sock, fds, 2);
511 if (ret < 0) {
512 perror("send consumer channel ancillary data");
513 goto error;
514 }
515
516 /* Send streams */
517 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
518 int fds[2];
519
520 if (!stream->obj->shm_fd) {
521 continue;
522 }
523 lum.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
524 lum.u.stream.channel_key = channel->obj->shm_fd;
525 lum.u.stream.stream_key = stream->obj->shm_fd;
526 lum.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
527 lum.u.stream.output = channel->attr.output;
528 lum.u.stream.mmap_len = stream->obj->memory_map_size;
529 strncpy(lum.u.stream.path_name, stream->pathname, PATH_MAX - 1);
530 lum.u.stream.path_name[PATH_MAX - 1] = '\0';
531 DBG("Sending stream %d to consumer", lum.u.stream.stream_key);
532 ret = lttcomm_send_unix_sock(sock, &lum, sizeof(lum));
533 if (ret < 0) {
534 perror("send consumer stream");
535 goto error;
536 }
537 fds[0] = stream->obj->shm_fd;
538 fds[1] = stream->obj->wait_fd;
539 ret = lttcomm_send_fds_unix_sock(sock, fds, 2);
540 if (ret < 0) {
541 perror("send consumer stream ancillary data");
542 goto error;
543 }
544 }
545
546 DBG("consumer channel streams sent");
547
548 return 0;
549
550 error:
551 return ret;
552 }
553
554 /*
555 * Send all stream fds of the kernel session to the consumer.
556 */
557 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
558 struct ltt_kernel_session *session)
559 {
560 int ret;
561 struct ltt_kernel_channel *chan;
562 struct lttcomm_consumer_msg lkm;
563 int sock = session->consumer_fd;
564
565 DBG("Sending metadata stream fd");
566
567 /* Extra protection. It's NOT supposed to be set to 0 at this point */
568 if (session->consumer_fd == 0) {
569 session->consumer_fd = consumer_data->cmd_sock;
570 }
571
572 if (session->metadata_stream_fd != 0) {
573 /* Send metadata channel fd */
574 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
575 lkm.u.channel.channel_key = session->metadata->fd;
576 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
577 lkm.u.channel.mmap_len = 0; /* for kernel */
578 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
579 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
580 if (ret < 0) {
581 perror("send consumer channel");
582 goto error;
583 }
584
585 /* Send metadata stream fd */
586 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
587 lkm.u.stream.channel_key = session->metadata->fd;
588 lkm.u.stream.stream_key = session->metadata_stream_fd;
589 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
590 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
591 lkm.u.stream.mmap_len = 0; /* for kernel */
592 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
593 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
594 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
595 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
596 if (ret < 0) {
597 perror("send consumer stream");
598 goto error;
599 }
600 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
601 if (ret < 0) {
602 perror("send consumer stream");
603 goto error;
604 }
605 }
606
607 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
608 ret = send_kconsumer_channel_streams(consumer_data, sock, chan);
609 if (ret < 0) {
610 goto error;
611 }
612 }
613
614 DBG("consumer fds (metadata and channel streams) sent");
615
616 return 0;
617
618 error:
619 return ret;
620 }
621
622 /*
623 * Send all stream fds of the UST session to the consumer.
624 */
625 static int send_ustconsumer_session_streams(struct consumer_data *consumer_data,
626 struct ltt_ust_session *session)
627 {
628 int ret;
629 struct ltt_ust_channel *chan;
630 struct lttcomm_consumer_msg lum;
631 int sock = session->consumer_fd;
632
633 DBG("Sending metadata stream fd");
634
635 /* Extra protection. It's NOT supposed to be set to 0 at this point */
636 if (session->consumer_fd == 0) {
637 session->consumer_fd = consumer_data->cmd_sock;
638 }
639
640 if (session->metadata->obj->shm_fd != 0) {
641 int fds[2];
642
643 /* Send metadata channel fd */
644 lum.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
645 lum.u.channel.channel_key = session->metadata->obj->shm_fd;
646 lum.u.channel.max_sb_size = session->metadata->attr.subbuf_size;
647 lum.u.channel.mmap_len = 0; /* for kernel */
648 DBG("Sending metadata channel %d to consumer", lum.u.stream.stream_key);
649 ret = lttcomm_send_unix_sock(sock, &lum, sizeof(lum));
650 if (ret < 0) {
651 perror("send consumer channel");
652 goto error;
653 }
654 fds[0] = session->metadata->obj->shm_fd;
655 fds[1] = session->metadata->obj->wait_fd;
656 ret = lttcomm_send_fds_unix_sock(sock, fds, 2);
657 if (ret < 0) {
658 perror("send consumer metadata channel");
659 goto error;
660 }
661
662 /* Send metadata stream fd */
663 lum.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
664 lum.u.stream.channel_key = session->metadata->obj->shm_fd;
665 lum.u.stream.stream_key = session->metadata->stream_obj->shm_fd;
666 lum.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
667 lum.u.stream.output = DEFAULT_UST_CHANNEL_OUTPUT;
668 lum.u.stream.mmap_len = session->metadata->stream_obj->memory_map_size;
669 strncpy(lum.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
670 lum.u.stream.path_name[PATH_MAX - 1] = '\0';
671 DBG("Sending metadata stream %d to consumer", lum.u.stream.stream_key);
672 ret = lttcomm_send_unix_sock(sock, &lum, sizeof(lum));
673 if (ret < 0) {
674 perror("send consumer metadata stream");
675 goto error;
676 }
677 fds[0] = session->metadata->stream_obj->shm_fd;
678 fds[1] = session->metadata->stream_obj->wait_fd;
679 ret = lttcomm_send_fds_unix_sock(sock, fds, 2);
680 if (ret < 0) {
681 perror("send consumer stream");
682 goto error;
683 }
684 }
685
686 cds_list_for_each_entry(chan, &session->channels.head, list) {
687 ret = send_ustconsumer_channel_streams(consumer_data, sock, chan);
688 if (ret < 0) {
689 goto error;
690 }
691 }
692
693 DBG("consumer fds (metadata and channel streams) sent");
694
695 return 0;
696
697 error:
698 return ret;
699 }
700
701 /*
702 * Notify UST applications using the shm mmap futex.
703 */
704 static int notify_ust_apps(int active)
705 {
706 char *wait_shm_mmap;
707
708 DBG("Notifying applications of session daemon state: %d", active);
709
710 /* See shm.c for this call implying mmap, shm and futex calls */
711 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
712 if (wait_shm_mmap == NULL) {
713 goto error;
714 }
715
716 /* Wake waiting process */
717 futex_wait_update((int32_t *) wait_shm_mmap, active);
718
719 /* Apps notified successfully */
720 return 0;
721
722 error:
723 return -1;
724 }
725
726 /*
727 * Setup the outgoing data buffer for the response (llm) by allocating the
728 * right amount of memory and copying the original information from the lsm
729 * structure.
730 *
731 * Return total size of the buffer pointed by buf.
732 */
733 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
734 {
735 int ret, buf_size;
736
737 buf_size = size;
738
739 cmd_ctx->llm = malloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
740 if (cmd_ctx->llm == NULL) {
741 perror("malloc");
742 ret = -ENOMEM;
743 goto error;
744 }
745
746 /* Copy common data */
747 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
748 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
749
750 cmd_ctx->llm->data_size = size;
751 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
752
753 return buf_size;
754
755 error:
756 return ret;
757 }
758
759 /*
760 * Update the kernel poll set of all channel fd available over all tracing
761 * session. Add the wakeup pipe at the end of the set.
762 */
763 static int update_kernel_poll(struct lttng_poll_event *events)
764 {
765 int ret;
766 struct ltt_session *session;
767 struct ltt_kernel_channel *channel;
768
769 DBG("Updating kernel poll set");
770
771 session_lock_list();
772 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
773 session_lock(session);
774 if (session->kernel_session == NULL) {
775 session_unlock(session);
776 continue;
777 }
778
779 cds_list_for_each_entry(channel,
780 &session->kernel_session->channel_list.head, list) {
781 /* Add channel fd to the kernel poll set */
782 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
783 if (ret < 0) {
784 session_unlock(session);
785 goto error;
786 }
787 DBG("Channel fd %d added to kernel set", channel->fd);
788 }
789 session_unlock(session);
790 }
791 session_unlock_list();
792
793 return 0;
794
795 error:
796 session_unlock_list();
797 return -1;
798 }
799
800 /*
801 * Find the channel fd from 'fd' over all tracing session. When found, check
802 * for new channel stream and send those stream fds to the kernel consumer.
803 *
804 * Useful for CPU hotplug feature.
805 */
806 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
807 {
808 int ret = 0;
809 struct ltt_session *session;
810 struct ltt_kernel_channel *channel;
811
812 DBG("Updating kernel streams for channel fd %d", fd);
813
814 session_lock_list();
815 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
816 session_lock(session);
817 if (session->kernel_session == NULL) {
818 session_unlock(session);
819 continue;
820 }
821
822 /* This is not suppose to be 0 but this is an extra security check */
823 if (session->kernel_session->consumer_fd == 0) {
824 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
825 }
826
827 cds_list_for_each_entry(channel,
828 &session->kernel_session->channel_list.head, list) {
829 if (channel->fd == fd) {
830 DBG("Channel found, updating kernel streams");
831 ret = kernel_open_channel_stream(channel);
832 if (ret < 0) {
833 goto error;
834 }
835
836 /*
837 * Have we already sent fds to the consumer? If yes, it means
838 * that tracing is started so it is safe to send our updated
839 * stream fds.
840 */
841 if (session->kernel_session->consumer_fds_sent == 1) {
842 ret = send_kconsumer_channel_streams(consumer_data,
843 session->kernel_session->consumer_fd, channel);
844 if (ret < 0) {
845 goto error;
846 }
847 }
848 goto error;
849 }
850 }
851 session_unlock(session);
852 }
853 session_unlock_list();
854 return ret;
855
856 error:
857 session_unlock(session);
858 session_unlock_list();
859 return ret;
860 }
861
862 /*
863 * This thread manage event coming from the kernel.
864 *
865 * Features supported in this thread:
866 * -) CPU Hotplug
867 */
868 static void *thread_manage_kernel(void *data)
869 {
870 int ret, i, pollfd, update_poll_flag = 1;
871 uint32_t revents, nb_fd;
872 char tmp;
873 struct lttng_poll_event events;
874
875 DBG("Thread manage kernel started");
876
877 ret = create_thread_poll_set(&events, 2);
878 if (ret < 0) {
879 goto error;
880 }
881
882 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
883 if (ret < 0) {
884 goto error;
885 }
886
887 while (1) {
888 if (update_poll_flag == 1) {
889 /*
890 * Reset number of fd in the poll set. Always 2 since there is the thread
891 * quit pipe and the kernel pipe.
892 */
893 events.nb_fd = 2;
894
895 ret = update_kernel_poll(&events);
896 if (ret < 0) {
897 goto error;
898 }
899 update_poll_flag = 0;
900 }
901
902 nb_fd = LTTNG_POLL_GETNB(&events);
903
904 DBG("Thread kernel polling on %d fds", nb_fd);
905
906 /* Zeroed the poll events */
907 lttng_poll_reset(&events);
908
909 /* Poll infinite value of time */
910 ret = lttng_poll_wait(&events, -1);
911 if (ret < 0) {
912 goto error;
913 } else if (ret == 0) {
914 /* Should not happen since timeout is infinite */
915 ERR("Return value of poll is 0 with an infinite timeout.\n"
916 "This should not have happened! Continuing...");
917 continue;
918 }
919
920 for (i = 0; i < nb_fd; i++) {
921 /* Fetch once the poll data */
922 revents = LTTNG_POLL_GETEV(&events, i);
923 pollfd = LTTNG_POLL_GETFD(&events, i);
924
925 /* Thread quit pipe has been closed. Killing thread. */
926 ret = check_thread_quit_pipe(pollfd, revents);
927 if (ret) {
928 goto error;
929 }
930
931 /* Check for data on kernel pipe */
932 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
933 ret = read(kernel_poll_pipe[0], &tmp, 1);
934 update_poll_flag = 1;
935 continue;
936 } else {
937 /*
938 * New CPU detected by the kernel. Adding kernel stream to
939 * kernel session and updating the kernel consumer
940 */
941 if (revents & LPOLLIN) {
942 ret = update_kernel_stream(&kconsumer_data, pollfd);
943 if (ret < 0) {
944 continue;
945 }
946 break;
947 /*
948 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
949 * and unregister kernel stream at this point.
950 */
951 }
952 }
953 }
954 }
955
956 error:
957 DBG("Kernel thread dying");
958 close(kernel_poll_pipe[0]);
959 close(kernel_poll_pipe[1]);
960
961 lttng_poll_clean(&events);
962
963 return NULL;
964 }
965
966 /*
967 * This thread manage the consumer error sent back to the session daemon.
968 */
969 static void *thread_manage_consumer(void *data)
970 {
971 int sock = 0, i, ret, pollfd;
972 uint32_t revents, nb_fd;
973 enum lttcomm_return_code code;
974 struct lttng_poll_event events;
975 struct consumer_data *consumer_data = data;
976
977 DBG("[thread] Manage consumer started");
978
979 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
980 if (ret < 0) {
981 goto error;
982 }
983
984 /*
985 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
986 * Nothing more will be added to this poll set.
987 */
988 ret = create_thread_poll_set(&events, 2);
989 if (ret < 0) {
990 goto error;
991 }
992
993 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
994 if (ret < 0) {
995 goto error;
996 }
997
998 nb_fd = LTTNG_POLL_GETNB(&events);
999
1000 /* Inifinite blocking call, waiting for transmission */
1001 ret = lttng_poll_wait(&events, -1);
1002 if (ret < 0) {
1003 goto error;
1004 }
1005
1006 for (i = 0; i < nb_fd; i++) {
1007 /* Fetch once the poll data */
1008 revents = LTTNG_POLL_GETEV(&events, i);
1009 pollfd = LTTNG_POLL_GETFD(&events, i);
1010
1011 /* Thread quit pipe has been closed. Killing thread. */
1012 ret = check_thread_quit_pipe(pollfd, revents);
1013 if (ret) {
1014 goto error;
1015 }
1016
1017 /* Event on the registration socket */
1018 if (pollfd == consumer_data->err_sock) {
1019 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1020 ERR("consumer err socket poll error");
1021 goto error;
1022 }
1023 }
1024 }
1025
1026 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
1027 if (sock < 0) {
1028 goto error;
1029 }
1030
1031 DBG2("Receiving code from consumer err_sock");
1032
1033 /* Getting status code from kconsumerd */
1034 ret = lttcomm_recv_unix_sock(sock, &code,
1035 sizeof(enum lttcomm_return_code));
1036 if (ret <= 0) {
1037 goto error;
1038 }
1039
1040 if (code == CONSUMERD_COMMAND_SOCK_READY) {
1041 consumer_data->cmd_sock =
1042 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
1043 if (consumer_data->cmd_sock < 0) {
1044 sem_post(&consumer_data->sem);
1045 perror("consumer connect");
1046 goto error;
1047 }
1048 /* Signal condition to tell that the kconsumerd is ready */
1049 sem_post(&consumer_data->sem);
1050 DBG("consumer command socket ready");
1051 } else {
1052 ERR("consumer error when waiting for SOCK_READY : %s",
1053 lttcomm_get_readable_code(-code));
1054 goto error;
1055 }
1056
1057 /* Remove the kconsumerd error sock since we've established a connexion */
1058 ret = lttng_poll_del(&events, consumer_data->err_sock);
1059 if (ret < 0) {
1060 goto error;
1061 }
1062
1063 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1064 if (ret < 0) {
1065 goto error;
1066 }
1067
1068 /* Update number of fd */
1069 nb_fd = LTTNG_POLL_GETNB(&events);
1070
1071 /* Inifinite blocking call, waiting for transmission */
1072 ret = lttng_poll_wait(&events, -1);
1073 if (ret < 0) {
1074 goto error;
1075 }
1076
1077 for (i = 0; i < nb_fd; i++) {
1078 /* Fetch once the poll data */
1079 revents = LTTNG_POLL_GETEV(&events, i);
1080 pollfd = LTTNG_POLL_GETFD(&events, i);
1081
1082 /* Thread quit pipe has been closed. Killing thread. */
1083 ret = check_thread_quit_pipe(pollfd, revents);
1084 if (ret) {
1085 goto error;
1086 }
1087
1088 /* Event on the kconsumerd socket */
1089 if (pollfd == sock) {
1090 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1091 ERR("consumer err socket second poll error");
1092 goto error;
1093 }
1094 }
1095 }
1096
1097 /* Wait for any kconsumerd error */
1098 ret = lttcomm_recv_unix_sock(sock, &code,
1099 sizeof(enum lttcomm_return_code));
1100 if (ret <= 0) {
1101 ERR("consumer closed the command socket");
1102 goto error;
1103 }
1104
1105 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1106
1107 error:
1108 DBG("consumer thread dying");
1109 close(consumer_data->err_sock);
1110 close(consumer_data->cmd_sock);
1111 close(sock);
1112
1113 unlink(consumer_data->err_unix_sock_path);
1114 unlink(consumer_data->cmd_unix_sock_path);
1115 consumer_data->pid = 0;
1116
1117 lttng_poll_clean(&events);
1118
1119 return NULL;
1120 }
1121
1122 /*
1123 * This thread manage application communication.
1124 */
1125 static void *thread_manage_apps(void *data)
1126 {
1127 int i, ret, pollfd;
1128 uint32_t revents, nb_fd;
1129 struct ust_command ust_cmd;
1130 struct lttng_poll_event events;
1131
1132 DBG("[thread] Manage application started");
1133
1134 ret = create_thread_poll_set(&events, 2);
1135 if (ret < 0) {
1136 goto error;
1137 }
1138
1139 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1140 if (ret < 0) {
1141 goto error;
1142 }
1143
1144 while (1) {
1145 /* Zeroed the events structure */
1146 lttng_poll_reset(&events);
1147
1148 nb_fd = LTTNG_POLL_GETNB(&events);
1149
1150 DBG("Apps thread polling on %d fds", nb_fd);
1151
1152 /* Inifinite blocking call, waiting for transmission */
1153 ret = lttng_poll_wait(&events, -1);
1154 if (ret < 0) {
1155 goto error;
1156 }
1157
1158 for (i = 0; i < nb_fd; i++) {
1159 /* Fetch once the poll data */
1160 revents = LTTNG_POLL_GETEV(&events, i);
1161 pollfd = LTTNG_POLL_GETFD(&events, i);
1162
1163 /* Thread quit pipe has been closed. Killing thread. */
1164 ret = check_thread_quit_pipe(pollfd, revents);
1165 if (ret) {
1166 goto error;
1167 }
1168
1169 /* Inspect the apps cmd pipe */
1170 if (pollfd == apps_cmd_pipe[0]) {
1171 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1172 ERR("Apps command pipe error");
1173 goto error;
1174 } else if (revents & LPOLLIN) {
1175 /* Empty pipe */
1176 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1177 if (ret < 0 || ret < sizeof(ust_cmd)) {
1178 perror("read apps cmd pipe");
1179 goto error;
1180 }
1181
1182 /* Register applicaton to the session daemon */
1183 ret = ust_app_register(&ust_cmd.reg_msg,
1184 ust_cmd.sock);
1185 if (ret < 0) {
1186 /* Only critical ENOMEM error can be returned here */
1187 goto error;
1188 }
1189
1190 ret = ustctl_register_done(ust_cmd.sock);
1191 if (ret < 0) {
1192 /*
1193 * If the registration is not possible, we simply
1194 * unregister the apps and continue
1195 */
1196 ust_app_unregister(ust_cmd.sock);
1197 } else {
1198 /*
1199 * We just need here to monitor the close of the UST
1200 * socket and poll set monitor those by default.
1201 */
1202 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1203 if (ret < 0) {
1204 goto error;
1205 }
1206
1207 DBG("Apps with sock %d added to poll set",
1208 ust_cmd.sock);
1209 }
1210 break;
1211 }
1212 } else {
1213 /*
1214 * At this point, we know that a registered application made
1215 * the event at poll_wait.
1216 */
1217 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1218 /* Removing from the poll set */
1219 ret = lttng_poll_del(&events, pollfd);
1220 if (ret < 0) {
1221 goto error;
1222 }
1223
1224 /* Socket closed */
1225 ust_app_unregister(pollfd);
1226 break;
1227 }
1228 }
1229 }
1230 }
1231
1232 error:
1233 DBG("Application communication apps dying");
1234 close(apps_cmd_pipe[0]);
1235 close(apps_cmd_pipe[1]);
1236
1237 lttng_poll_clean(&events);
1238
1239 return NULL;
1240 }
1241
1242 /*
1243 * Dispatch request from the registration threads to the application
1244 * communication thread.
1245 */
1246 static void *thread_dispatch_ust_registration(void *data)
1247 {
1248 int ret;
1249 struct cds_wfq_node *node;
1250 struct ust_command *ust_cmd = NULL;
1251
1252 DBG("[thread] Dispatch UST command started");
1253
1254 while (!dispatch_thread_exit) {
1255 /* Atomically prepare the queue futex */
1256 futex_nto1_prepare(&ust_cmd_queue.futex);
1257
1258 do {
1259 /* Dequeue command for registration */
1260 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1261 if (node == NULL) {
1262 DBG("Woken up but nothing in the UST command queue");
1263 /* Continue thread execution */
1264 break;
1265 }
1266
1267 ust_cmd = caa_container_of(node, struct ust_command, node);
1268
1269 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1270 " gid:%d sock:%d name:%s (version %d.%d)",
1271 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1272 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1273 ust_cmd->sock, ust_cmd->reg_msg.name,
1274 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1275 /*
1276 * Inform apps thread of the new application registration. This
1277 * call is blocking so we can be assured that the data will be read
1278 * at some point in time or wait to the end of the world :)
1279 */
1280 ret = write(apps_cmd_pipe[1], ust_cmd,
1281 sizeof(struct ust_command));
1282 if (ret < 0) {
1283 perror("write apps cmd pipe");
1284 if (errno == EBADF) {
1285 /*
1286 * We can't inform the application thread to process
1287 * registration. We will exit or else application
1288 * registration will not occur and tracing will never
1289 * start.
1290 */
1291 goto error;
1292 }
1293 }
1294 free(ust_cmd);
1295 } while (node != NULL);
1296
1297 /* Futex wait on queue. Blocking call on futex() */
1298 futex_nto1_wait(&ust_cmd_queue.futex);
1299 }
1300
1301 error:
1302 DBG("Dispatch thread dying");
1303 return NULL;
1304 }
1305
1306 /*
1307 * This thread manage application registration.
1308 */
1309 static void *thread_registration_apps(void *data)
1310 {
1311 int sock = 0, i, ret, pollfd;
1312 uint32_t revents, nb_fd;
1313 struct lttng_poll_event events;
1314 /*
1315 * Get allocated in this thread, enqueued to a global queue, dequeued and
1316 * freed in the manage apps thread.
1317 */
1318 struct ust_command *ust_cmd = NULL;
1319
1320 DBG("[thread] Manage application registration started");
1321
1322 ret = lttcomm_listen_unix_sock(apps_sock);
1323 if (ret < 0) {
1324 goto error;
1325 }
1326
1327 /*
1328 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1329 * more will be added to this poll set.
1330 */
1331 ret = create_thread_poll_set(&events, 2);
1332 if (ret < 0) {
1333 goto error;
1334 }
1335
1336 /* Add the application registration socket */
1337 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1338 if (ret < 0) {
1339 goto error;
1340 }
1341
1342 /* Notify all applications to register */
1343 ret = notify_ust_apps(1);
1344 if (ret < 0) {
1345 ERR("Failed to notify applications or create the wait shared memory.\n"
1346 "Execution continues but there might be problem for already\n"
1347 "running applications that wishes to register.");
1348 }
1349
1350 while (1) {
1351 DBG("Accepting application registration");
1352
1353 nb_fd = LTTNG_POLL_GETNB(&events);
1354
1355 /* Inifinite blocking call, waiting for transmission */
1356 ret = lttng_poll_wait(&events, -1);
1357 if (ret < 0) {
1358 goto error;
1359 }
1360
1361 for (i = 0; i < nb_fd; i++) {
1362 /* Fetch once the poll data */
1363 revents = LTTNG_POLL_GETEV(&events, i);
1364 pollfd = LTTNG_POLL_GETFD(&events, i);
1365
1366 /* Thread quit pipe has been closed. Killing thread. */
1367 ret = check_thread_quit_pipe(pollfd, revents);
1368 if (ret) {
1369 goto error;
1370 }
1371
1372 /* Event on the registration socket */
1373 if (pollfd == apps_sock) {
1374 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1375 ERR("Register apps socket poll error");
1376 goto error;
1377 } else if (revents & LPOLLIN) {
1378 sock = lttcomm_accept_unix_sock(apps_sock);
1379 if (sock < 0) {
1380 goto error;
1381 }
1382
1383 /* Create UST registration command for enqueuing */
1384 ust_cmd = malloc(sizeof(struct ust_command));
1385 if (ust_cmd == NULL) {
1386 perror("ust command malloc");
1387 goto error;
1388 }
1389
1390 /*
1391 * Using message-based transmissions to ensure we don't
1392 * have to deal with partially received messages.
1393 */
1394 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1395 sizeof(struct ust_register_msg));
1396 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1397 if (ret < 0) {
1398 perror("lttcomm_recv_unix_sock register apps");
1399 } else {
1400 ERR("Wrong size received on apps register");
1401 }
1402 free(ust_cmd);
1403 close(sock);
1404 continue;
1405 }
1406
1407 ust_cmd->sock = sock;
1408
1409 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1410 " gid:%d sock:%d name:%s (version %d.%d)",
1411 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1412 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1413 ust_cmd->sock, ust_cmd->reg_msg.name,
1414 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1415
1416 /*
1417 * Lock free enqueue the registration request. The red pill
1418 * has been taken! This apps will be part of the *system*.
1419 */
1420 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1421
1422 /*
1423 * Wake the registration queue futex. Implicit memory
1424 * barrier with the exchange in cds_wfq_enqueue.
1425 */
1426 futex_nto1_wake(&ust_cmd_queue.futex);
1427 }
1428 }
1429 }
1430 }
1431
1432 error:
1433 DBG("UST Registration thread dying");
1434
1435 /* Notify that the registration thread is gone */
1436 notify_ust_apps(0);
1437
1438 close(apps_sock);
1439 close(sock);
1440 unlink(apps_unix_sock_path);
1441
1442 lttng_poll_clean(&events);
1443
1444 return NULL;
1445 }
1446
1447 /*
1448 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1449 * exec or it will fails.
1450 */
1451 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1452 {
1453 int ret;
1454 struct timespec timeout;
1455
1456 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1457 timeout.tv_nsec = 0;
1458
1459 /* Setup semaphore */
1460 ret = sem_init(&consumer_data->sem, 0, 0);
1461 if (ret < 0) {
1462 PERROR("sem_init consumer semaphore");
1463 goto error;
1464 }
1465
1466 ret = pthread_create(&consumer_data->thread, NULL,
1467 thread_manage_consumer, consumer_data);
1468 if (ret != 0) {
1469 PERROR("pthread_create consumer");
1470 ret = -1;
1471 goto error;
1472 }
1473
1474 /* Get time for sem_timedwait absolute timeout */
1475 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1476 if (ret < 0) {
1477 PERROR("clock_gettime spawn consumer");
1478 /* Infinite wait for the kconsumerd thread to be ready */
1479 ret = sem_wait(&consumer_data->sem);
1480 } else {
1481 /* Normal timeout if the gettime was successful */
1482 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1483 ret = sem_timedwait(&consumer_data->sem, &timeout);
1484 }
1485
1486 if (ret < 0) {
1487 if (errno == ETIMEDOUT) {
1488 /*
1489 * Call has timed out so we kill the kconsumerd_thread and return
1490 * an error.
1491 */
1492 ERR("The consumer thread was never ready. Killing it");
1493 ret = pthread_cancel(consumer_data->thread);
1494 if (ret < 0) {
1495 PERROR("pthread_cancel consumer thread");
1496 }
1497 } else {
1498 PERROR("semaphore wait failed consumer thread");
1499 }
1500 goto error;
1501 }
1502
1503 pthread_mutex_lock(&consumer_data->pid_mutex);
1504 if (consumer_data->pid == 0) {
1505 ERR("Kconsumerd did not start");
1506 pthread_mutex_unlock(&consumer_data->pid_mutex);
1507 goto error;
1508 }
1509 pthread_mutex_unlock(&consumer_data->pid_mutex);
1510
1511 return 0;
1512
1513 error:
1514 return ret;
1515 }
1516
1517 /*
1518 * Join consumer thread
1519 */
1520 static int join_consumer_thread(struct consumer_data *consumer_data)
1521 {
1522 void *status;
1523 int ret;
1524
1525 if (consumer_data->pid != 0) {
1526 ret = kill(consumer_data->pid, SIGTERM);
1527 if (ret) {
1528 ERR("Error killing consumer daemon");
1529 return ret;
1530 }
1531 return pthread_join(consumer_data->thread, &status);
1532 } else {
1533 return 0;
1534 }
1535 }
1536
1537 /*
1538 * Fork and exec a consumer daemon (consumerd).
1539 *
1540 * Return pid if successful else -1.
1541 */
1542 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1543 {
1544 int ret;
1545 pid_t pid;
1546 const char *verbosity;
1547
1548 DBG("Spawning consumerd");
1549
1550 pid = fork();
1551 if (pid == 0) {
1552 /*
1553 * Exec consumerd.
1554 */
1555 if (opt_verbose > 1 || opt_verbose_consumer) {
1556 verbosity = "--verbose";
1557 } else {
1558 verbosity = "--quiet";
1559 }
1560 switch (consumer_data->type) {
1561 case LTTNG_CONSUMER_KERNEL:
1562 execl(INSTALL_BIN_PATH "/lttng-consumerd",
1563 "lttng-consumerd", verbosity, "-k", NULL);
1564 break;
1565 case LTTNG_CONSUMER_UST:
1566 execl(INSTALL_BIN_PATH "/lttng-consumerd",
1567 "lttng-consumerd", verbosity, "-u", NULL);
1568 break;
1569 default:
1570 perror("unknown consumer type");
1571 exit(EXIT_FAILURE);
1572 }
1573 if (errno != 0) {
1574 perror("kernel start consumer exec");
1575 }
1576 exit(EXIT_FAILURE);
1577 } else if (pid > 0) {
1578 ret = pid;
1579 } else {
1580 perror("start consumer fork");
1581 ret = -errno;
1582 }
1583 return ret;
1584 }
1585
1586 /*
1587 * Spawn the consumerd daemon and session daemon thread.
1588 */
1589 static int start_consumerd(struct consumer_data *consumer_data)
1590 {
1591 int ret;
1592
1593 pthread_mutex_lock(&consumer_data->pid_mutex);
1594 if (consumer_data->pid != 0) {
1595 pthread_mutex_unlock(&consumer_data->pid_mutex);
1596 goto end;
1597 }
1598
1599 ret = spawn_consumerd(consumer_data);
1600 if (ret < 0) {
1601 ERR("Spawning consumerd failed");
1602 pthread_mutex_unlock(&consumer_data->pid_mutex);
1603 goto error;
1604 }
1605
1606 /* Setting up the consumer_data pid */
1607 consumer_data->pid = ret;
1608 DBG2("consumer pid %d", consumer_data->pid);
1609 pthread_mutex_unlock(&consumer_data->pid_mutex);
1610
1611 DBG2("Spawning consumer control thread");
1612 ret = spawn_consumer_thread(consumer_data);
1613 if (ret < 0) {
1614 ERR("Fatal error spawning consumer control thread");
1615 goto error;
1616 }
1617
1618 end:
1619 return 0;
1620
1621 error:
1622 return ret;
1623 }
1624
1625 /*
1626 * modprobe_kernel_modules
1627 */
1628 static int modprobe_kernel_modules(void)
1629 {
1630 int ret = 0, i;
1631 char modprobe[256];
1632
1633 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1634 ret = snprintf(modprobe, sizeof(modprobe),
1635 "/sbin/modprobe %s%s",
1636 kernel_modules_list[i].required ? "" : "--quiet ",
1637 kernel_modules_list[i].name);
1638 if (ret < 0) {
1639 perror("snprintf modprobe");
1640 goto error;
1641 }
1642 modprobe[sizeof(modprobe) - 1] = '\0';
1643 ret = system(modprobe);
1644 if (ret == -1) {
1645 ERR("Unable to launch modprobe for module %s",
1646 kernel_modules_list[i].name);
1647 } else if (kernel_modules_list[i].required
1648 && WEXITSTATUS(ret) != 0) {
1649 ERR("Unable to load module %s",
1650 kernel_modules_list[i].name);
1651 } else {
1652 DBG("Modprobe successfully %s",
1653 kernel_modules_list[i].name);
1654 }
1655 }
1656
1657 error:
1658 return ret;
1659 }
1660
1661 /*
1662 * mount_debugfs
1663 */
1664 static int mount_debugfs(char *path)
1665 {
1666 int ret;
1667 char *type = "debugfs";
1668
1669 ret = mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1670 if (ret < 0) {
1671 PERROR("Cannot create debugfs path");
1672 goto error;
1673 }
1674
1675 ret = mount(type, path, type, 0, NULL);
1676 if (ret < 0) {
1677 PERROR("Cannot mount debugfs");
1678 goto error;
1679 }
1680
1681 DBG("Mounted debugfs successfully at %s", path);
1682
1683 error:
1684 return ret;
1685 }
1686
1687 /*
1688 * Setup necessary data for kernel tracer action.
1689 */
1690 static void init_kernel_tracer(void)
1691 {
1692 int ret;
1693 char *proc_mounts = "/proc/mounts";
1694 char line[256];
1695 char *debugfs_path = NULL, *lttng_path = NULL;
1696 FILE *fp;
1697
1698 /* Detect debugfs */
1699 fp = fopen(proc_mounts, "r");
1700 if (fp == NULL) {
1701 ERR("Unable to probe %s", proc_mounts);
1702 goto error;
1703 }
1704
1705 while (fgets(line, sizeof(line), fp) != NULL) {
1706 if (strstr(line, "debugfs") != NULL) {
1707 /* Remove first string */
1708 strtok(line, " ");
1709 /* Dup string here so we can reuse line later on */
1710 debugfs_path = strdup(strtok(NULL, " "));
1711 DBG("Got debugfs path : %s", debugfs_path);
1712 break;
1713 }
1714 }
1715
1716 fclose(fp);
1717
1718 /* Mount debugfs if needded */
1719 if (debugfs_path == NULL) {
1720 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1721 if (ret < 0) {
1722 perror("asprintf debugfs path");
1723 goto error;
1724 }
1725 ret = mount_debugfs(debugfs_path);
1726 if (ret < 0) {
1727 perror("Cannot mount debugfs");
1728 goto error;
1729 }
1730 }
1731
1732 /* Modprobe lttng kernel modules */
1733 ret = modprobe_kernel_modules();
1734 if (ret < 0) {
1735 goto error;
1736 }
1737
1738 /* Setup lttng kernel path */
1739 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1740 if (ret < 0) {
1741 perror("asprintf lttng path");
1742 goto error;
1743 }
1744
1745 /* Open debugfs lttng */
1746 kernel_tracer_fd = open(lttng_path, O_RDWR);
1747 if (kernel_tracer_fd < 0) {
1748 DBG("Failed to open %s", lttng_path);
1749 goto error;
1750 }
1751
1752 free(lttng_path);
1753 free(debugfs_path);
1754 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1755 return;
1756
1757 error:
1758 if (lttng_path) {
1759 free(lttng_path);
1760 }
1761 if (debugfs_path) {
1762 free(debugfs_path);
1763 }
1764 WARN("No kernel tracer available");
1765 kernel_tracer_fd = 0;
1766 return;
1767 }
1768
1769 /*
1770 * Init tracing by creating trace directory and sending fds kernel consumer.
1771 */
1772 static int init_kernel_tracing(struct ltt_kernel_session *session)
1773 {
1774 int ret = 0;
1775
1776 if (session->consumer_fds_sent == 0) {
1777 /*
1778 * Assign default kernel consumer socket if no consumer assigned to the
1779 * kernel session. At this point, it's NOT suppose to be 0 but this is
1780 * an extra security check.
1781 */
1782 if (session->consumer_fd == 0) {
1783 session->consumer_fd = kconsumer_data.cmd_sock;
1784 }
1785
1786 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1787 if (ret < 0) {
1788 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1789 goto error;
1790 }
1791
1792 session->consumer_fds_sent = 1;
1793 }
1794
1795 error:
1796 return ret;
1797 }
1798
1799 /*
1800 * Init tracing by creating trace directory and sending fds ust consumer.
1801 */
1802 static int init_ust_tracing(struct ltt_ust_session *session)
1803 {
1804 int ret = 0;
1805
1806 if (session->consumer_fds_sent == 0) {
1807 /*
1808 * Assign default ust consumer socket if no consumer assigned to the
1809 * ust session. At this point, it's NOT suppose to be 0 but this is
1810 * an extra security check.
1811 */
1812 if (session->consumer_fd == 0) {
1813 session->consumer_fd = ustconsumer_data.cmd_sock;
1814 }
1815
1816 ret = send_ustconsumer_session_streams(&ustconsumer_data, session);
1817 if (ret < 0) {
1818 ret = LTTCOMM_UST_CONSUMER_FAIL;
1819 goto error;
1820 }
1821
1822 session->consumer_fds_sent = 1;
1823 }
1824
1825 error:
1826 return ret;
1827 }
1828
1829 /*
1830 * Create an UST session and add it to the session ust list.
1831 */
1832 static int create_ust_session(struct ltt_session *session,
1833 struct lttng_domain *domain)
1834 {
1835 int ret;
1836 struct ltt_ust_session *lus = NULL;
1837 struct ust_app *app;
1838
1839 switch (domain->type) {
1840 case LTTNG_DOMAIN_UST_PID:
1841 app = ust_app_get_by_pid(domain->attr.pid);
1842 if (app == NULL) {
1843 ret = LTTCOMM_APP_NOT_FOUND;
1844 goto error;
1845 }
1846 break;
1847 default:
1848 ret = LTTCOMM_UNKNOWN_DOMAIN;
1849 goto error;
1850 }
1851
1852 DBG("Creating UST session");
1853
1854 lus = trace_ust_create_session(session->path, domain->attr.pid, domain);
1855 if (lus == NULL) {
1856 ret = LTTCOMM_UST_SESS_FAIL;
1857 goto error;
1858 }
1859
1860 ret = mkdir_recursive(lus->path, S_IRWXU | S_IRWXG,
1861 geteuid(), allowed_group());
1862 if (ret < 0) {
1863 if (ret != -EEXIST) {
1864 ERR("Trace directory creation error");
1865 ret = LTTCOMM_UST_SESS_FAIL;
1866 goto error;
1867 }
1868 }
1869
1870 /* Create session on the UST tracer */
1871 ret = ustctl_create_session(app->sock);
1872 if (ret < 0) {
1873 ret = LTTCOMM_UST_SESS_FAIL;
1874 goto error;
1875 }
1876 lus->handle = ret;
1877 lus->sock = app->sock;
1878
1879 cds_list_add(&lus->list, &session->ust_session_list.head);
1880 session->ust_session_list.count++;
1881
1882 return LTTCOMM_OK;
1883
1884 error:
1885 free(lus);
1886 return ret;
1887 }
1888
1889 /*
1890 * Create a kernel tracer session then create the default channel.
1891 */
1892 static int create_kernel_session(struct ltt_session *session)
1893 {
1894 int ret;
1895
1896 DBG("Creating kernel session");
1897
1898 ret = kernel_create_session(session, kernel_tracer_fd);
1899 if (ret < 0) {
1900 ret = LTTCOMM_KERN_SESS_FAIL;
1901 goto error;
1902 }
1903
1904 /* Set kernel consumer socket fd */
1905 if (kconsumer_data.cmd_sock) {
1906 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1907 }
1908
1909 ret = mkdir_recursive(session->kernel_session->trace_path,
1910 S_IRWXU | S_IRWXG, geteuid(), allowed_group());
1911 if (ret < 0) {
1912 if (ret != -EEXIST) {
1913 ERR("Trace directory creation error");
1914 goto error;
1915 }
1916 }
1917
1918 error:
1919 return ret;
1920 }
1921
1922 /*
1923 * Using the session list, filled a lttng_session array to send back to the
1924 * client for session listing.
1925 *
1926 * The session list lock MUST be acquired before calling this function. Use
1927 * session_lock_list() and session_unlock_list().
1928 */
1929 static void list_lttng_sessions(struct lttng_session *sessions)
1930 {
1931 int i = 0;
1932 struct ltt_session *session;
1933
1934 DBG("Getting all available session");
1935 /*
1936 * Iterate over session list and append data after the control struct in
1937 * the buffer.
1938 */
1939 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1940 strncpy(sessions[i].path, session->path, PATH_MAX);
1941 sessions[i].path[PATH_MAX - 1] = '\0';
1942 strncpy(sessions[i].name, session->name, NAME_MAX);
1943 sessions[i].name[NAME_MAX - 1] = '\0';
1944 i++;
1945 }
1946 }
1947
1948 /*
1949 * Fill lttng_channel array of all channels.
1950 */
1951 static void list_lttng_channels(struct ltt_session *session,
1952 struct lttng_channel *channels)
1953 {
1954 int i = 0;
1955 struct ltt_kernel_channel *kchan;
1956
1957 DBG("Listing channels for session %s", session->name);
1958
1959 /* Kernel channels */
1960 if (session->kernel_session != NULL) {
1961 cds_list_for_each_entry(kchan,
1962 &session->kernel_session->channel_list.head, list) {
1963 /* Copy lttng_channel struct to array */
1964 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
1965 channels[i].enabled = kchan->enabled;
1966 i++;
1967 }
1968 }
1969
1970 /* TODO: Missing UST listing */
1971 }
1972
1973 /*
1974 * Fill lttng_event array of all events in the channel.
1975 */
1976 static void list_lttng_events(struct ltt_kernel_channel *kchan,
1977 struct lttng_event *events)
1978 {
1979 /*
1980 * TODO: This is ONLY kernel. Need UST support.
1981 */
1982 int i = 0;
1983 struct ltt_kernel_event *event;
1984
1985 DBG("Listing events for channel %s", kchan->channel->name);
1986
1987 /* Kernel channels */
1988 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
1989 strncpy(events[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
1990 events[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
1991 events[i].enabled = event->enabled;
1992 switch (event->event->instrumentation) {
1993 case LTTNG_KERNEL_TRACEPOINT:
1994 events[i].type = LTTNG_EVENT_TRACEPOINT;
1995 break;
1996 case LTTNG_KERNEL_KPROBE:
1997 case LTTNG_KERNEL_KRETPROBE:
1998 events[i].type = LTTNG_EVENT_PROBE;
1999 memcpy(&events[i].attr.probe, &event->event->u.kprobe,
2000 sizeof(struct lttng_kernel_kprobe));
2001 break;
2002 case LTTNG_KERNEL_FUNCTION:
2003 events[i].type = LTTNG_EVENT_FUNCTION;
2004 memcpy(&events[i].attr.ftrace, &event->event->u.ftrace,
2005 sizeof(struct lttng_kernel_function));
2006 break;
2007 case LTTNG_KERNEL_NOOP:
2008 events[i].type = LTTNG_EVENT_NOOP;
2009 break;
2010 case LTTNG_KERNEL_SYSCALL:
2011 events[i].type = LTTNG_EVENT_SYSCALL;
2012 break;
2013 case LTTNG_KERNEL_ALL:
2014 assert(0);
2015 break;
2016 }
2017 i++;
2018 }
2019 }
2020
2021 /*
2022 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2023 */
2024 static int cmd_disable_channel(struct ltt_session *session,
2025 int domain, char *channel_name)
2026 {
2027 int ret;
2028
2029 switch (domain) {
2030 case LTTNG_DOMAIN_KERNEL:
2031 ret = channel_kernel_disable(session->kernel_session,
2032 channel_name);
2033 if (ret != LTTCOMM_OK) {
2034 goto error;
2035 }
2036
2037 kernel_wait_quiescent(kernel_tracer_fd);
2038 break;
2039 case LTTNG_DOMAIN_UST_PID:
2040 break;
2041 default:
2042 ret = LTTCOMM_UNKNOWN_DOMAIN;
2043 goto error;
2044 }
2045
2046 ret = LTTCOMM_OK;
2047
2048 error:
2049 return ret;
2050 }
2051
2052 /*
2053 * Copy channel from attributes and set it in the application channel list.
2054 */
2055 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
2056 struct lttng_channel *attr, struct ust_app *app)
2057 {
2058 int ret;
2059 struct ltt_ust_channel *uchan, *new_chan;
2060
2061 uchan = trace_ust_get_channel_by_name(attr->name, usess);
2062 if (uchan == NULL) {
2063 ret = LTTCOMM_FATAL;
2064 goto error;
2065 }
2066
2067 new_chan = trace_ust_create_channel(attr, usess->path);
2068 if (new_chan == NULL) {
2069 PERROR("malloc ltt_ust_channel");
2070 ret = LTTCOMM_FATAL;
2071 goto error;
2072 }
2073
2074 ret = channel_ust_copy(new_chan, uchan);
2075 if (ret < 0) {
2076 ret = LTTCOMM_FATAL;
2077 goto error;
2078 }
2079
2080 /* Add channel to the ust app channel list */
2081 cds_list_add(&new_chan->list, &app->channels.head);
2082 app->channels.count++;
2083
2084 error:
2085 return ret;
2086 }
2087
2088 /*
2089 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2090 */
2091 static int cmd_enable_channel(struct ltt_session *session,
2092 struct lttng_domain *domain, struct lttng_channel *attr)
2093 {
2094 int ret;
2095
2096 switch (domain->type) {
2097 case LTTNG_DOMAIN_KERNEL:
2098 {
2099 struct ltt_kernel_channel *kchan;
2100
2101 kchan = trace_kernel_get_channel_by_name(attr->name,
2102 session->kernel_session);
2103 if (kchan == NULL) {
2104 ret = channel_kernel_create(session->kernel_session,
2105 attr, kernel_poll_pipe[1]);
2106 } else {
2107 ret = channel_kernel_enable(session->kernel_session, kchan);
2108 }
2109
2110 if (ret != LTTCOMM_OK) {
2111 goto error;
2112 }
2113
2114 kernel_wait_quiescent(kernel_tracer_fd);
2115 break;
2116 }
2117 case LTTNG_DOMAIN_UST_PID:
2118 {
2119 int sock;
2120 struct ltt_ust_channel *uchan;
2121 struct ltt_ust_session *usess;
2122 struct ust_app *app;
2123
2124 usess = trace_ust_get_session_by_pid(&session->ust_session_list,
2125 domain->attr.pid);
2126 if (usess == NULL) {
2127 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2128 goto error;
2129 }
2130
2131 app = ust_app_get_by_pid(domain->attr.pid);
2132 if (app == NULL) {
2133 ret = LTTCOMM_APP_NOT_FOUND;
2134 goto error;
2135 }
2136 sock = app->sock;
2137
2138 uchan = trace_ust_get_channel_by_name(attr->name, usess);
2139 if (uchan == NULL) {
2140 ret = channel_ust_create(usess, attr, sock);
2141 } else {
2142 ret = channel_ust_enable(usess, uchan, sock);
2143 }
2144
2145 if (ret != LTTCOMM_OK) {
2146 goto error;
2147 }
2148
2149 ret = copy_ust_channel_to_app(usess, attr, app);
2150 if (ret != LTTCOMM_OK) {
2151 goto error;
2152 }
2153
2154 DBG("UST channel %s created for app sock %d with pid %d",
2155 attr->name, app->sock, domain->attr.pid);
2156 break;
2157 }
2158 default:
2159 ret = LTTCOMM_UNKNOWN_DOMAIN;
2160 goto error;
2161 }
2162
2163 ret = LTTCOMM_OK;
2164
2165 error:
2166 return ret;
2167 }
2168
2169 /*
2170 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2171 */
2172 static int cmd_disable_event(struct ltt_session *session, int domain,
2173 char *channel_name, char *event_name)
2174 {
2175 int ret;
2176
2177 switch (domain) {
2178 case LTTNG_DOMAIN_KERNEL:
2179 {
2180 struct ltt_kernel_channel *kchan;
2181
2182 kchan = trace_kernel_get_channel_by_name(channel_name,
2183 session->kernel_session);
2184 if (kchan == NULL) {
2185 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2186 goto error;
2187 }
2188
2189 ret = event_kernel_disable_tracepoint(session->kernel_session, kchan, event_name);
2190 if (ret != LTTCOMM_OK) {
2191 goto error;
2192 }
2193
2194 kernel_wait_quiescent(kernel_tracer_fd);
2195 break;
2196 }
2197 case LTTNG_DOMAIN_UST:
2198 {
2199 struct ltt_ust_session *ustsession;
2200
2201 cds_list_for_each_entry(ustsession, &session->ust_session_list.head, list) {
2202 struct ltt_ust_channel *ustchan;
2203
2204 ustchan = trace_ust_get_channel_by_name(channel_name,
2205 ustsession);
2206 if (ustchan == NULL) {
2207 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2208 goto error;
2209 }
2210 ret = event_ust_disable_tracepoint(ustsession, ustchan, event_name);
2211 if (ret != LTTCOMM_OK) {
2212 goto error;
2213 }
2214
2215 ustctl_wait_quiescent(ustsession->sock);
2216 }
2217 break;
2218 }
2219 case LTTNG_DOMAIN_UST_EXEC_NAME:
2220 case LTTNG_DOMAIN_UST_PID:
2221 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2222 default:
2223 /* TODO: Other UST domains */
2224 ret = LTTCOMM_NOT_IMPLEMENTED;
2225 goto error;
2226 }
2227
2228 ret = LTTCOMM_OK;
2229
2230 error:
2231 return ret;
2232 }
2233
2234 /*
2235 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2236 */
2237 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2238 char *channel_name)
2239 {
2240 int ret;
2241 struct ltt_kernel_channel *kchan;
2242
2243 switch (domain) {
2244 case LTTNG_DOMAIN_KERNEL:
2245 kchan = trace_kernel_get_channel_by_name(channel_name,
2246 session->kernel_session);
2247 if (kchan == NULL) {
2248 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2249 goto error;
2250 }
2251
2252 ret = event_kernel_disable_all(session->kernel_session, kchan);
2253 if (ret != LTTCOMM_OK) {
2254 goto error;
2255 }
2256
2257 kernel_wait_quiescent(kernel_tracer_fd);
2258 break;
2259 default:
2260 /* TODO: Userspace tracing */
2261 ret = LTTCOMM_NOT_IMPLEMENTED;
2262 goto error;
2263 }
2264
2265 ret = LTTCOMM_OK;
2266
2267 error:
2268 return ret;
2269 }
2270
2271 /*
2272 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2273 */
2274 static int cmd_add_context(struct ltt_session *session, int domain,
2275 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2276 {
2277 int ret;
2278
2279 switch (domain) {
2280 case LTTNG_DOMAIN_KERNEL:
2281 /* Add kernel context to kernel tracer */
2282 ret = context_kernel_add(session->kernel_session, ctx,
2283 event_name, channel_name);
2284 if (ret != LTTCOMM_OK) {
2285 goto error;
2286 }
2287 break;
2288 case LTTNG_DOMAIN_UST:
2289 {
2290 struct ltt_ust_session *ustsession;
2291
2292 cds_list_for_each_entry(ustsession, &session->ust_session_list.head, list) {
2293 /* Add UST context to UST tracer */
2294 ret = context_ust_add(ustsession, ctx,
2295 event_name, channel_name);
2296 if (ret != LTTCOMM_OK) {
2297 goto error;
2298 }
2299 }
2300 break;
2301 }
2302 default:
2303 /* TODO: UST other domains */
2304 ret = LTTCOMM_NOT_IMPLEMENTED;
2305 goto error;
2306 }
2307
2308 ret = LTTCOMM_OK;
2309
2310 error:
2311 return ret;
2312 }
2313
2314 /*
2315 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2316 */
2317 static int cmd_enable_event(struct ltt_session *session, int domain,
2318 char *channel_name, struct lttng_event *event)
2319 {
2320 int ret;
2321 struct lttng_channel *attr;
2322
2323 switch (domain) {
2324 case LTTNG_DOMAIN_KERNEL:
2325 {
2326 struct ltt_kernel_channel *kchan;
2327
2328 kchan = trace_kernel_get_channel_by_name(channel_name,
2329 session->kernel_session);
2330 if (kchan == NULL) {
2331 attr = channel_new_default_attr(domain);
2332 if (attr == NULL) {
2333 ret = LTTCOMM_FATAL;
2334 goto error;
2335 }
2336 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2337
2338 /* This call will notify the kernel thread */
2339 ret = channel_kernel_create(session->kernel_session,
2340 attr, kernel_poll_pipe[1]);
2341 if (ret != LTTCOMM_OK) {
2342 goto error;
2343 }
2344 }
2345
2346 /* Get the newly created kernel channel pointer */
2347 kchan = trace_kernel_get_channel_by_name(channel_name,
2348 session->kernel_session);
2349 if (kchan == NULL) {
2350 /* This sould not happen... */
2351 ret = LTTCOMM_FATAL;
2352 goto error;
2353 }
2354
2355 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan, event);
2356 if (ret != LTTCOMM_OK) {
2357 goto error;
2358 }
2359
2360 kernel_wait_quiescent(kernel_tracer_fd);
2361 break;
2362 }
2363 case LTTNG_DOMAIN_UST:
2364 {
2365 struct ltt_ust_session *ustsession;
2366
2367 cds_list_for_each_entry(ustsession, &session->ust_session_list.head, list) {
2368 struct ltt_ust_channel *ustchan;
2369
2370 ustchan = trace_ust_get_channel_by_name(channel_name,
2371 ustsession);
2372 if (ustchan == NULL) {
2373 attr = channel_new_default_attr(domain);
2374 if (attr == NULL) {
2375 ret = LTTCOMM_FATAL;
2376 goto error;
2377 }
2378 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2379
2380 ret = channel_ust_create(ustsession,
2381 attr, ustsession->sock);
2382 if (ret != LTTCOMM_OK) {
2383 goto error;
2384 }
2385 }
2386
2387 /* Get the newly created ust channel pointer */
2388 ustchan = trace_ust_get_channel_by_name(channel_name,
2389 ustsession);
2390 if (ustchan == NULL) {
2391 /* This sould not happen... */
2392 ret = LTTCOMM_FATAL;
2393 goto error;
2394 }
2395
2396 ret = event_ust_enable_tracepoint(ustsession, ustchan, event);
2397 if (ret != LTTCOMM_OK) {
2398 goto error;
2399 }
2400
2401 ustctl_wait_quiescent(ustsession->sock);
2402 }
2403 break;
2404 }
2405 case LTTNG_DOMAIN_UST_EXEC_NAME:
2406 case LTTNG_DOMAIN_UST_PID:
2407 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2408 default:
2409 /* TODO: UST other domains */
2410 ret = LTTCOMM_NOT_IMPLEMENTED;
2411 goto error;
2412 }
2413
2414 ret = LTTCOMM_OK;
2415
2416 error:
2417 return ret;
2418 }
2419
2420 /*
2421 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2422 */
2423 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2424 char *channel_name, int event_type)
2425 {
2426 int ret;
2427 struct ltt_kernel_channel *kchan;
2428
2429 switch (domain) {
2430 case LTTNG_DOMAIN_KERNEL:
2431 kchan = trace_kernel_get_channel_by_name(channel_name,
2432 session->kernel_session);
2433 if (kchan == NULL) {
2434 /* This call will notify the kernel thread */
2435 ret = channel_kernel_create(session->kernel_session, NULL,
2436 kernel_poll_pipe[1]);
2437 if (ret != LTTCOMM_OK) {
2438 goto error;
2439 }
2440 }
2441
2442 /* Get the newly created kernel channel pointer */
2443 kchan = trace_kernel_get_channel_by_name(channel_name,
2444 session->kernel_session);
2445 if (kchan == NULL) {
2446 /* This sould not happen... */
2447 ret = LTTCOMM_FATAL;
2448 goto error;
2449 }
2450
2451 switch (event_type) {
2452 case LTTNG_KERNEL_SYSCALL:
2453 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2454 kchan, kernel_tracer_fd);
2455 break;
2456 case LTTNG_KERNEL_TRACEPOINT:
2457 /*
2458 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2459 * events already registered to the channel.
2460 */
2461 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2462 kchan, kernel_tracer_fd);
2463 break;
2464 case LTTNG_KERNEL_ALL:
2465 /* Enable syscalls and tracepoints */
2466 ret = event_kernel_enable_all(session->kernel_session,
2467 kchan, kernel_tracer_fd);
2468 break;
2469 default:
2470 ret = LTTCOMM_KERN_ENABLE_FAIL;
2471 goto error;
2472 }
2473 if (ret != LTTCOMM_OK) {
2474 goto error;
2475 }
2476
2477 kernel_wait_quiescent(kernel_tracer_fd);
2478 break;
2479 default:
2480 /* TODO: Userspace tracing */
2481 ret = LTTCOMM_NOT_IMPLEMENTED;
2482 goto error;
2483 }
2484
2485 ret = LTTCOMM_OK;
2486
2487 error:
2488 return ret;
2489 }
2490
2491 /*
2492 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2493 */
2494 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2495 {
2496 int ret;
2497 ssize_t nb_events = 0;
2498
2499 switch (domain) {
2500 case LTTNG_DOMAIN_KERNEL:
2501 nb_events = kernel_list_events(kernel_tracer_fd, events);
2502 if (nb_events < 0) {
2503 ret = LTTCOMM_KERN_LIST_FAIL;
2504 goto error;
2505 }
2506 break;
2507 default:
2508 /* TODO: Userspace listing */
2509 ret = LTTCOMM_NOT_IMPLEMENTED;
2510 goto error;
2511 }
2512
2513 return nb_events;
2514
2515 error:
2516 /* Return negative value to differentiate return code */
2517 return -ret;
2518 }
2519
2520 /*
2521 * Command LTTNG_START_TRACE processed by the client thread.
2522 */
2523 static int cmd_start_trace(struct ltt_session *session)
2524 {
2525 int ret;
2526 struct ltt_kernel_session *ksession;
2527 struct ltt_ust_session *ustsession;
2528
2529 /* Short cut */
2530 ksession = session->kernel_session;
2531
2532 /* Kernel tracing */
2533 if (ksession != NULL) {
2534 struct ltt_kernel_channel *kchan;
2535
2536 /* Open kernel metadata */
2537 if (ksession->metadata == NULL) {
2538 ret = kernel_open_metadata(ksession, ksession->trace_path);
2539 if (ret < 0) {
2540 ret = LTTCOMM_KERN_META_FAIL;
2541 goto error;
2542 }
2543 }
2544
2545 /* Open kernel metadata stream */
2546 if (ksession->metadata_stream_fd == 0) {
2547 ret = kernel_open_metadata_stream(ksession);
2548 if (ret < 0) {
2549 ERR("Kernel create metadata stream failed");
2550 ret = LTTCOMM_KERN_STREAM_FAIL;
2551 goto error;
2552 }
2553 }
2554
2555 /* For each channel */
2556 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2557 if (kchan->stream_count == 0) {
2558 ret = kernel_open_channel_stream(kchan);
2559 if (ret < 0) {
2560 ret = LTTCOMM_KERN_STREAM_FAIL;
2561 goto error;
2562 }
2563 /* Update the stream global counter */
2564 ksession->stream_count_global += ret;
2565 }
2566 }
2567
2568 /* Setup kernel consumer socket and send fds to it */
2569 ret = init_kernel_tracing(ksession);
2570 if (ret < 0) {
2571 ret = LTTCOMM_KERN_START_FAIL;
2572 goto error;
2573 }
2574
2575 /* This start the kernel tracing */
2576 ret = kernel_start_session(ksession);
2577 if (ret < 0) {
2578 ret = LTTCOMM_KERN_START_FAIL;
2579 goto error;
2580 }
2581
2582 /* Quiescent wait after starting trace */
2583 kernel_wait_quiescent(kernel_tracer_fd);
2584 }
2585
2586 /* Start all UST traces */
2587 cds_list_for_each_entry(ustsession, &session->ust_session_list.head, list) {
2588 struct ltt_ust_channel *ustchan;
2589
2590 /* Open kernel metadata */
2591 if (ustsession->metadata == NULL) {
2592 struct lttng_ust_channel_attr ustattr;
2593
2594 /* Allocate UST metadata */
2595 ustsession->metadata = trace_ust_create_metadata(ustsession->path);
2596 if (ustsession->metadata == NULL) {
2597 ret = LTTCOMM_UST_META_FAIL;
2598 goto error;
2599 }
2600
2601 ustattr.overwrite = ustsession->metadata->attr.overwrite;
2602 ustattr.subbuf_size = ustsession->metadata->attr.subbuf_size;
2603 ustattr.num_subbuf = ustsession->metadata->attr.num_subbuf;
2604 ustattr.switch_timer_interval = ustsession->metadata->attr.switch_timer_interval;
2605 ustattr.read_timer_interval = ustsession->metadata->attr.read_timer_interval;
2606 ustattr.output = ustsession->metadata->attr.output;
2607
2608 /* UST tracer metadata creation */
2609 ret = ustctl_open_metadata(ustsession->sock,
2610 ustsession->handle, &ustattr,
2611 &ustsession->metadata->obj);
2612 if (ret < 0) {
2613 ret = LTTCOMM_UST_META_FAIL;
2614 goto error;
2615 }
2616 }
2617
2618 /* Open UST metadata stream */
2619 if (ustsession->metadata->stream_obj == NULL) {
2620 ret = ustctl_create_stream(ustsession->sock,
2621 ustsession->metadata->obj,
2622 &ustsession->metadata->stream_obj);
2623 if (ret < 0) {
2624 ERR("UST create metadata stream failed");
2625 ret = LTTCOMM_UST_STREAM_FAIL;
2626 goto error;
2627 }
2628 ret = asprintf(&ustsession->metadata->pathname, "%s/%s",
2629 ustsession->path, "metadata");
2630 if (ret < 0) {
2631 perror("asprintf UST create stream");
2632 goto error;
2633 }
2634 }
2635
2636 /* For each channel */
2637 cds_list_for_each_entry(ustchan, &ustsession->channels.head, list) {
2638 if (ustchan->stream_count == 0) {
2639 struct ltt_ust_stream *ustream;
2640
2641 ustream = zmalloc(sizeof(*ustream));
2642 if (!ustream) {
2643 ret = LTTCOMM_UST_STREAM_FAIL;
2644 goto error;
2645 }
2646 ret = ustctl_create_stream(ustsession->sock,
2647 ustchan->obj, &ustream->obj);
2648 if (ret < 0) {
2649 ret = LTTCOMM_UST_STREAM_FAIL;
2650 goto error;
2651 }
2652 ret = asprintf(&ustream->pathname, "%s/%s_%d",
2653 ustchan->trace_path, ustchan->name,
2654 ustchan->stream_count);
2655 if (ret < 0) {
2656 perror("asprintf UST create stream");
2657 goto error;
2658 }
2659 cds_list_add(&ustream->list, &ustchan->stream_list.head);
2660 ustchan->stream_count++;
2661 }
2662 }
2663
2664 /* Setup UST consumer socket and send fds to it */
2665 ret = init_ust_tracing(ustsession);
2666 if (ret < 0) {
2667 ret = LTTCOMM_UST_START_FAIL;
2668 goto error;
2669 }
2670
2671 /* This start the UST tracing */
2672 ret = ustctl_start_session(ustsession->sock, ustsession->handle);
2673 if (ret < 0) {
2674 ret = LTTCOMM_UST_START_FAIL;
2675 goto error;
2676 }
2677
2678 /* Quiescent wait after starting trace */
2679 ustctl_wait_quiescent(ustsession->sock);
2680 }
2681
2682 ret = LTTCOMM_OK;
2683
2684 error:
2685 return ret;
2686 }
2687
2688 /*
2689 * Command LTTNG_STOP_TRACE processed by the client thread.
2690 */
2691 static int cmd_stop_trace(struct ltt_session *session)
2692 {
2693 int ret;
2694 struct ltt_kernel_channel *kchan;
2695 struct ltt_kernel_session *ksession;
2696 struct ltt_ust_session *ustsession;
2697 struct ltt_ust_channel *ustchan;
2698
2699 /* Short cut */
2700 ksession = session->kernel_session;
2701
2702 /* Kernel tracer */
2703 if (ksession != NULL) {
2704 DBG("Stop kernel tracing");
2705
2706 /* Flush all buffers before stopping */
2707 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2708 if (ret < 0) {
2709 ERR("Kernel metadata flush failed");
2710 }
2711
2712 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2713 ret = kernel_flush_buffer(kchan);
2714 if (ret < 0) {
2715 ERR("Kernel flush buffer error");
2716 }
2717 }
2718
2719 ret = kernel_stop_session(ksession);
2720 if (ret < 0) {
2721 ret = LTTCOMM_KERN_STOP_FAIL;
2722 goto error;
2723 }
2724
2725 kernel_wait_quiescent(kernel_tracer_fd);
2726 }
2727
2728 /* Stop each UST session */
2729 DBG("Stop UST tracing");
2730 cds_list_for_each_entry(ustsession, &session->ust_session_list.head, list) {
2731 /* Flush all buffers before stopping */
2732 ret = ustctl_flush_buffer(ustsession->sock, ustsession->metadata->obj);
2733 if (ret < 0) {
2734 ERR("UST metadata flush failed");
2735 }
2736
2737 cds_list_for_each_entry(ustchan, &ustsession->channels.head, list) {
2738 ret = ustctl_flush_buffer(ustsession->sock, ustchan->obj);
2739 if (ret < 0) {
2740 ERR("UST flush buffer error");
2741 }
2742 }
2743
2744 ret = ustctl_stop_session(ustsession->sock, ustsession->handle);
2745 if (ret < 0) {
2746 ret = LTTCOMM_KERN_STOP_FAIL;
2747 goto error;
2748 }
2749
2750 ustctl_wait_quiescent(ustsession->sock);
2751 }
2752
2753 ret = LTTCOMM_OK;
2754
2755 error:
2756 return ret;
2757 }
2758
2759 /*
2760 * Command LTTNG_CREATE_SESSION processed by the client thread.
2761 */
2762 static int cmd_create_session(char *name, char *path)
2763 {
2764 int ret;
2765
2766 ret = session_create(name, path);
2767 if (ret != LTTCOMM_OK) {
2768 goto error;
2769 }
2770
2771 ret = LTTCOMM_OK;
2772
2773 error:
2774 return ret;
2775 }
2776
2777 /*
2778 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2779 */
2780 static int cmd_destroy_session(struct ltt_session *session, char *name)
2781 {
2782 int ret;
2783
2784 /* Clean kernel session teardown */
2785 teardown_kernel_session(session);
2786
2787 /*
2788 * Must notify the kernel thread here to update it's poll setin order
2789 * to remove the channel(s)' fd just destroyed.
2790 */
2791 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2792 if (ret < 0) {
2793 perror("write kernel poll pipe");
2794 }
2795
2796 ret = session_destroy(session);
2797
2798 return ret;
2799 }
2800
2801 /*
2802 * Command LTTNG_CALIBRATE processed by the client thread.
2803 */
2804 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2805 {
2806 int ret;
2807
2808 switch (domain) {
2809 case LTTNG_DOMAIN_KERNEL:
2810 {
2811 struct lttng_kernel_calibrate kcalibrate;
2812
2813 kcalibrate.type = calibrate->type;
2814 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2815 if (ret < 0) {
2816 ret = LTTCOMM_KERN_ENABLE_FAIL;
2817 goto error;
2818 }
2819 break;
2820 }
2821 default:
2822 /* TODO: Userspace tracing */
2823 ret = LTTCOMM_NOT_IMPLEMENTED;
2824 goto error;
2825 }
2826
2827 ret = LTTCOMM_OK;
2828
2829 error:
2830 return ret;
2831 }
2832
2833 /*
2834 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2835 */
2836 static int cmd_register_consumer(struct ltt_session *session, int domain,
2837 char *sock_path)
2838 {
2839 int ret, sock;
2840
2841 switch (domain) {
2842 case LTTNG_DOMAIN_KERNEL:
2843 /* Can't register a consumer if there is already one */
2844 if (session->kernel_session->consumer_fd != 0) {
2845 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2846 goto error;
2847 }
2848
2849 sock = lttcomm_connect_unix_sock(sock_path);
2850 if (sock < 0) {
2851 ret = LTTCOMM_CONNECT_FAIL;
2852 goto error;
2853 }
2854
2855 session->kernel_session->consumer_fd = sock;
2856 break;
2857 default:
2858 /* TODO: Userspace tracing */
2859 ret = LTTCOMM_NOT_IMPLEMENTED;
2860 goto error;
2861 }
2862
2863 ret = LTTCOMM_OK;
2864
2865 error:
2866 return ret;
2867 }
2868
2869 /*
2870 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2871 */
2872 static ssize_t cmd_list_domains(struct ltt_session *session,
2873 struct lttng_domain **domains)
2874 {
2875 int ret;
2876 ssize_t nb_dom = 0;
2877
2878 if (session->kernel_session != NULL) {
2879 nb_dom++;
2880 }
2881
2882 nb_dom += session->ust_session_list.count;
2883
2884 *domains = malloc(nb_dom * sizeof(struct lttng_domain));
2885 if (*domains == NULL) {
2886 ret = -LTTCOMM_FATAL;
2887 goto error;
2888 }
2889
2890 (*domains)[0].type = LTTNG_DOMAIN_KERNEL;
2891
2892 /* TODO: User-space tracer domain support */
2893
2894 return nb_dom;
2895
2896 error:
2897 return ret;
2898 }
2899
2900 /*
2901 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2902 */
2903 static ssize_t cmd_list_channels(struct ltt_session *session,
2904 struct lttng_channel **channels)
2905 {
2906 int ret;
2907 ssize_t nb_chan = 0;
2908
2909 if (session->kernel_session != NULL) {
2910 nb_chan += session->kernel_session->channel_count;
2911 }
2912
2913 *channels = malloc(nb_chan * sizeof(struct lttng_channel));
2914 if (*channels == NULL) {
2915 ret = -LTTCOMM_FATAL;
2916 goto error;
2917 }
2918
2919 list_lttng_channels(session, *channels);
2920
2921 /* TODO UST support */
2922
2923 return nb_chan;
2924
2925 error:
2926 return ret;
2927 }
2928
2929 /*
2930 * Command LTTNG_LIST_EVENTS processed by the client thread.
2931 */
2932 static ssize_t cmd_list_events(struct ltt_session *session,
2933 char *channel_name, struct lttng_event **events)
2934 {
2935 int ret;
2936 ssize_t nb_event = 0;
2937 struct ltt_kernel_channel *kchan = NULL;
2938
2939 if (session->kernel_session != NULL) {
2940 kchan = trace_kernel_get_channel_by_name(channel_name,
2941 session->kernel_session);
2942 if (kchan == NULL) {
2943 ret = -LTTCOMM_KERN_CHAN_NOT_FOUND;
2944 goto error;
2945 }
2946 nb_event += kchan->event_count;
2947 }
2948
2949 *events = malloc(nb_event * sizeof(struct lttng_event));
2950 if (*events == NULL) {
2951 ret = -LTTCOMM_FATAL;
2952 goto error;
2953 }
2954
2955 list_lttng_events(kchan, *events);
2956
2957 /* TODO: User-space tracer support */
2958
2959 return nb_event;
2960
2961 error:
2962 return ret;
2963 }
2964
2965 /*
2966 * Process the command requested by the lttng client within the command
2967 * context structure. This function make sure that the return structure (llm)
2968 * is set and ready for transmission before returning.
2969 *
2970 * Return any error encountered or 0 for success.
2971 */
2972 static int process_client_msg(struct command_ctx *cmd_ctx)
2973 {
2974 int ret = LTTCOMM_OK;
2975 int need_tracing_session = 1;
2976
2977 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
2978
2979 /*
2980 * Check for command that don't needs to allocate a returned payload. We do
2981 * this here so we don't have to make the call for no payload at each
2982 * command.
2983 */
2984 switch(cmd_ctx->lsm->cmd_type) {
2985 case LTTNG_LIST_SESSIONS:
2986 case LTTNG_LIST_TRACEPOINTS:
2987 case LTTNG_LIST_DOMAINS:
2988 case LTTNG_LIST_CHANNELS:
2989 case LTTNG_LIST_EVENTS:
2990 break;
2991 default:
2992 /* Setup lttng message with no payload */
2993 ret = setup_lttng_msg(cmd_ctx, 0);
2994 if (ret < 0) {
2995 /* This label does not try to unlock the session */
2996 goto init_setup_error;
2997 }
2998 }
2999
3000 /* Commands that DO NOT need a session. */
3001 switch (cmd_ctx->lsm->cmd_type) {
3002 case LTTNG_CALIBRATE:
3003 case LTTNG_CREATE_SESSION:
3004 case LTTNG_LIST_SESSIONS:
3005 case LTTNG_LIST_TRACEPOINTS:
3006 need_tracing_session = 0;
3007 break;
3008 default:
3009 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3010 session_lock_list();
3011 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3012 session_unlock_list();
3013 if (cmd_ctx->session == NULL) {
3014 if (cmd_ctx->lsm->session.name != NULL) {
3015 ret = LTTCOMM_SESS_NOT_FOUND;
3016 } else {
3017 /* If no session name specified */
3018 ret = LTTCOMM_SELECT_SESS;
3019 }
3020 goto error;
3021 } else {
3022 /* Acquire lock for the session */
3023 session_lock(cmd_ctx->session);
3024 }
3025 break;
3026 }
3027
3028 /*
3029 * Check domain type for specific "pre-action".
3030 */
3031 switch (cmd_ctx->lsm->domain.type) {
3032 case LTTNG_DOMAIN_KERNEL:
3033 /* Kernel tracer check */
3034 if (kernel_tracer_fd == 0) {
3035 /* Basically, load kernel tracer modules */
3036 init_kernel_tracer();
3037 if (kernel_tracer_fd == 0) {
3038 ret = LTTCOMM_KERN_NA;
3039 goto error;
3040 }
3041 }
3042
3043 /* Need a session for kernel command */
3044 if (need_tracing_session) {
3045 if (cmd_ctx->session->kernel_session == NULL) {
3046 ret = create_kernel_session(cmd_ctx->session);
3047 if (ret < 0) {
3048 ret = LTTCOMM_KERN_SESS_FAIL;
3049 goto error;
3050 }
3051 }
3052
3053 /* Start the kernel consumer daemon */
3054 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3055 if (kconsumer_data.pid == 0 &&
3056 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3057 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3058 ret = start_consumerd(&kconsumer_data);
3059 if (ret < 0) {
3060 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3061 goto error;
3062 }
3063 }
3064 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3065 }
3066 break;
3067 case LTTNG_DOMAIN_UST:
3068 case LTTNG_DOMAIN_UST_EXEC_NAME:
3069 case LTTNG_DOMAIN_UST_PID:
3070 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
3071 {
3072 struct ltt_ust_session *usess;
3073
3074 if (need_tracing_session) {
3075 usess = trace_ust_get_session_by_pid(
3076 &cmd_ctx->session->ust_session_list,
3077 cmd_ctx->lsm->domain.attr.pid);
3078 if (usess == NULL) {
3079 ret = create_ust_session(cmd_ctx->session,
3080 &cmd_ctx->lsm->domain);
3081 if (ret != LTTCOMM_OK) {
3082 goto error;
3083 }
3084 }
3085 /* Start the kernel consumer daemon */
3086 pthread_mutex_lock(&ustconsumer_data.pid_mutex);
3087 if (ustconsumer_data.pid == 0 &&
3088 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3089 pthread_mutex_unlock(&ustconsumer_data.pid_mutex);
3090 ret = start_consumerd(&ustconsumer_data);
3091 if (ret < 0) {
3092 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3093 goto error;
3094 }
3095 }
3096 pthread_mutex_unlock(&ustconsumer_data.pid_mutex);
3097 }
3098 break;
3099 }
3100 default:
3101 break;
3102 }
3103
3104 /* Process by command type */
3105 switch (cmd_ctx->lsm->cmd_type) {
3106 case LTTNG_ADD_CONTEXT:
3107 {
3108 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3109 cmd_ctx->lsm->u.context.channel_name,
3110 cmd_ctx->lsm->u.context.event_name,
3111 &cmd_ctx->lsm->u.context.ctx);
3112 break;
3113 }
3114 case LTTNG_DISABLE_CHANNEL:
3115 {
3116 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3117 cmd_ctx->lsm->u.disable.channel_name);
3118 break;
3119 }
3120 case LTTNG_DISABLE_EVENT:
3121 {
3122 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3123 cmd_ctx->lsm->u.disable.channel_name,
3124 cmd_ctx->lsm->u.disable.name);
3125 ret = LTTCOMM_OK;
3126 break;
3127 }
3128 case LTTNG_DISABLE_ALL_EVENT:
3129 {
3130 DBG("Disabling all events");
3131
3132 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3133 cmd_ctx->lsm->u.disable.channel_name);
3134 break;
3135 }
3136 case LTTNG_ENABLE_CHANNEL:
3137 {
3138 ret = cmd_enable_channel(cmd_ctx->session, &cmd_ctx->lsm->domain,
3139 &cmd_ctx->lsm->u.channel.chan);
3140 break;
3141 }
3142 case LTTNG_ENABLE_EVENT:
3143 {
3144 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3145 cmd_ctx->lsm->u.enable.channel_name,
3146 &cmd_ctx->lsm->u.enable.event);
3147 break;
3148 }
3149 case LTTNG_ENABLE_ALL_EVENT:
3150 {
3151 DBG("Enabling all events");
3152
3153 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3154 cmd_ctx->lsm->u.enable.channel_name,
3155 cmd_ctx->lsm->u.enable.event.type);
3156 break;
3157 }
3158 case LTTNG_LIST_TRACEPOINTS:
3159 {
3160 struct lttng_event *events;
3161 ssize_t nb_events;
3162
3163 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3164 if (nb_events < 0) {
3165 ret = -nb_events;
3166 goto error;
3167 }
3168
3169 /*
3170 * Setup lttng message with payload size set to the event list size in
3171 * bytes and then copy list into the llm payload.
3172 */
3173 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3174 if (ret < 0) {
3175 free(events);
3176 goto setup_error;
3177 }
3178
3179 /* Copy event list into message payload */
3180 memcpy(cmd_ctx->llm->payload, events,
3181 sizeof(struct lttng_event) * nb_events);
3182
3183 free(events);
3184
3185 ret = LTTCOMM_OK;
3186 break;
3187 }
3188 case LTTNG_START_TRACE:
3189 {
3190 ret = cmd_start_trace(cmd_ctx->session);
3191 break;
3192 }
3193 case LTTNG_STOP_TRACE:
3194 {
3195 ret = cmd_stop_trace(cmd_ctx->session);
3196 break;
3197 }
3198 case LTTNG_CREATE_SESSION:
3199 {
3200 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3201 cmd_ctx->lsm->session.path);
3202 break;
3203 }
3204 case LTTNG_DESTROY_SESSION:
3205 {
3206 ret = cmd_destroy_session(cmd_ctx->session,
3207 cmd_ctx->lsm->session.name);
3208 break;
3209 }
3210 case LTTNG_LIST_DOMAINS:
3211 {
3212 ssize_t nb_dom;
3213 struct lttng_domain *domains;
3214
3215 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3216 if (nb_dom < 0) {
3217 ret = -nb_dom;
3218 goto error;
3219 }
3220
3221 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3222 if (ret < 0) {
3223 goto setup_error;
3224 }
3225
3226 /* Copy event list into message payload */
3227 memcpy(cmd_ctx->llm->payload, domains,
3228 nb_dom * sizeof(struct lttng_domain));
3229
3230 free(domains);
3231
3232 ret = LTTCOMM_OK;
3233 break;
3234 }
3235 case LTTNG_LIST_CHANNELS:
3236 {
3237 size_t nb_chan;
3238 struct lttng_channel *channels;
3239
3240 nb_chan = cmd_list_channels(cmd_ctx->session, &channels);
3241 if (nb_chan < 0) {
3242 ret = -nb_chan;
3243 goto error;
3244 }
3245
3246 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3247 if (ret < 0) {
3248 goto setup_error;
3249 }
3250
3251 /* Copy event list into message payload */
3252 memcpy(cmd_ctx->llm->payload, channels,
3253 nb_chan * sizeof(struct lttng_channel));
3254
3255 free(channels);
3256
3257 ret = LTTCOMM_OK;
3258 break;
3259 }
3260 case LTTNG_LIST_EVENTS:
3261 {
3262 size_t nb_event;
3263 struct lttng_event *events = NULL;
3264
3265 nb_event = cmd_list_events(cmd_ctx->session,
3266 cmd_ctx->lsm->u.list.channel_name, &events);
3267 if (nb_event < 0) {
3268 ret = -nb_event;
3269 goto error;
3270 }
3271
3272 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3273 if (ret < 0) {
3274 goto setup_error;
3275 }
3276
3277 /* Copy event list into message payload */
3278 memcpy(cmd_ctx->llm->payload, events,
3279 nb_event * sizeof(struct lttng_event));
3280
3281 free(events);
3282
3283 ret = LTTCOMM_OK;
3284 break;
3285 }
3286 case LTTNG_LIST_SESSIONS:
3287 {
3288 session_lock_list();
3289
3290 if (session_list_ptr->count == 0) {
3291 ret = LTTCOMM_NO_SESSION;
3292 session_unlock_list();
3293 goto error;
3294 }
3295
3296 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) *
3297 session_list_ptr->count);
3298 if (ret < 0) {
3299 session_unlock_list();
3300 goto setup_error;
3301 }
3302
3303 /* Filled the session array */
3304 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
3305
3306 session_unlock_list();
3307
3308 ret = LTTCOMM_OK;
3309 break;
3310 }
3311 case LTTNG_CALIBRATE:
3312 {
3313 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3314 &cmd_ctx->lsm->u.calibrate);
3315 break;
3316 }
3317 case LTTNG_REGISTER_CONSUMER:
3318 {
3319 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3320 cmd_ctx->lsm->u.reg.path);
3321 break;
3322 }
3323 default:
3324 ret = LTTCOMM_UND;
3325 break;
3326 }
3327
3328 error:
3329 if (cmd_ctx->llm == NULL) {
3330 DBG("Missing llm structure. Allocating one.");
3331 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3332 goto setup_error;
3333 }
3334 }
3335 /* Set return code */
3336 cmd_ctx->llm->ret_code = ret;
3337 setup_error:
3338 if (cmd_ctx->session) {
3339 session_unlock(cmd_ctx->session);
3340 }
3341 init_setup_error:
3342 return ret;
3343 }
3344
3345 /*
3346 * This thread manage all clients request using the unix client socket for
3347 * communication.
3348 */
3349 static void *thread_manage_clients(void *data)
3350 {
3351 int sock = 0, ret, i, pollfd;
3352 uint32_t revents, nb_fd;
3353 struct command_ctx *cmd_ctx = NULL;
3354 struct lttng_poll_event events;
3355
3356 DBG("[thread] Manage client started");
3357
3358 ret = lttcomm_listen_unix_sock(client_sock);
3359 if (ret < 0) {
3360 goto error;
3361 }
3362
3363 /*
3364 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3365 * more will be added to this poll set.
3366 */
3367 ret = create_thread_poll_set(&events, 2);
3368 if (ret < 0) {
3369 goto error;
3370 }
3371
3372 /* Add the application registration socket */
3373 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3374 if (ret < 0) {
3375 goto error;
3376 }
3377
3378 /*
3379 * Notify parent pid that we are ready to accept command for client side.
3380 */
3381 if (opt_sig_parent) {
3382 kill(ppid, SIGCHLD);
3383 }
3384
3385 while (1) {
3386 DBG("Accepting client command ...");
3387
3388 nb_fd = LTTNG_POLL_GETNB(&events);
3389
3390 /* Inifinite blocking call, waiting for transmission */
3391 ret = lttng_poll_wait(&events, -1);
3392 if (ret < 0) {
3393 goto error;
3394 }
3395
3396 for (i = 0; i < nb_fd; i++) {
3397 /* Fetch once the poll data */
3398 revents = LTTNG_POLL_GETEV(&events, i);
3399 pollfd = LTTNG_POLL_GETFD(&events, i);
3400
3401 /* Thread quit pipe has been closed. Killing thread. */
3402 ret = check_thread_quit_pipe(pollfd, revents);
3403 if (ret) {
3404 goto error;
3405 }
3406
3407 /* Event on the registration socket */
3408 if (pollfd == client_sock) {
3409 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3410 ERR("Client socket poll error");
3411 goto error;
3412 }
3413 }
3414 }
3415
3416 DBG("Wait for client response");
3417
3418 sock = lttcomm_accept_unix_sock(client_sock);
3419 if (sock < 0) {
3420 goto error;
3421 }
3422
3423 /* Allocate context command to process the client request */
3424 cmd_ctx = malloc(sizeof(struct command_ctx));
3425 if (cmd_ctx == NULL) {
3426 perror("malloc cmd_ctx");
3427 goto error;
3428 }
3429
3430 /* Allocate data buffer for reception */
3431 cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg));
3432 if (cmd_ctx->lsm == NULL) {
3433 perror("malloc cmd_ctx->lsm");
3434 goto error;
3435 }
3436
3437 cmd_ctx->llm = NULL;
3438 cmd_ctx->session = NULL;
3439
3440 /*
3441 * Data is received from the lttng client. The struct
3442 * lttcomm_session_msg (lsm) contains the command and data request of
3443 * the client.
3444 */
3445 DBG("Receiving data from client ...");
3446 ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm,
3447 sizeof(struct lttcomm_session_msg));
3448 if (ret <= 0) {
3449 DBG("Nothing recv() from client... continuing");
3450 close(sock);
3451 free(cmd_ctx);
3452 continue;
3453 }
3454
3455 // TODO: Validate cmd_ctx including sanity check for
3456 // security purpose.
3457
3458 /*
3459 * This function dispatch the work to the kernel or userspace tracer
3460 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3461 * informations for the client. The command context struct contains
3462 * everything this function may needs.
3463 */
3464 ret = process_client_msg(cmd_ctx);
3465 if (ret < 0) {
3466 /*
3467 * TODO: Inform client somehow of the fatal error. At
3468 * this point, ret < 0 means that a malloc failed
3469 * (ENOMEM). Error detected but still accept command.
3470 */
3471 clean_command_ctx(&cmd_ctx);
3472 continue;
3473 }
3474
3475 DBG("Sending response (size: %d, retcode: %s)",
3476 cmd_ctx->lttng_msg_size,
3477 lttng_strerror(-cmd_ctx->llm->ret_code));
3478 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3479 if (ret < 0) {
3480 ERR("Failed to send data back to client");
3481 }
3482
3483 clean_command_ctx(&cmd_ctx);
3484
3485 /* End of transmission */
3486 close(sock);
3487 }
3488
3489 error:
3490 DBG("Client thread dying");
3491 unlink(client_unix_sock_path);
3492 close(client_sock);
3493 close(sock);
3494
3495 lttng_poll_clean(&events);
3496 clean_command_ctx(&cmd_ctx);
3497 return NULL;
3498 }
3499
3500
3501 /*
3502 * usage function on stderr
3503 */
3504 static void usage(void)
3505 {
3506 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3507 fprintf(stderr, " -h, --help Display this usage.\n");
3508 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3509 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3510 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3511 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3512 fprintf(stderr, " --ustconsumerd-err-sock PATH Specify path for the UST consumer error socket\n");
3513 fprintf(stderr, " --ustconsumerd-cmd-sock PATH Specify path for the UST consumer command socket\n");
3514 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3515 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3516 fprintf(stderr, " -V, --version Show version number.\n");
3517 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3518 fprintf(stderr, " -q, --quiet No output at all.\n");
3519 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3520 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3521 }
3522
3523 /*
3524 * daemon argument parsing
3525 */
3526 static int parse_args(int argc, char **argv)
3527 {
3528 int c;
3529
3530 static struct option long_options[] = {
3531 { "client-sock", 1, 0, 'c' },
3532 { "apps-sock", 1, 0, 'a' },
3533 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3534 { "kconsumerd-err-sock", 1, 0, 'E' },
3535 { "ustconsumerd-cmd-sock", 1, 0, 'D' },
3536 { "ustconsumerd-err-sock", 1, 0, 'F' },
3537 { "daemonize", 0, 0, 'd' },
3538 { "sig-parent", 0, 0, 'S' },
3539 { "help", 0, 0, 'h' },
3540 { "group", 1, 0, 'g' },
3541 { "version", 0, 0, 'V' },
3542 { "quiet", 0, 0, 'q' },
3543 { "verbose", 0, 0, 'v' },
3544 { "verbose-consumer", 0, 0, 'Z' },
3545 { NULL, 0, 0, 0 }
3546 };
3547
3548 while (1) {
3549 int option_index = 0;
3550 c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:C:E:D:F:Z",
3551 long_options, &option_index);
3552 if (c == -1) {
3553 break;
3554 }
3555
3556 switch (c) {
3557 case 0:
3558 fprintf(stderr, "option %s", long_options[option_index].name);
3559 if (optarg) {
3560 fprintf(stderr, " with arg %s\n", optarg);
3561 }
3562 break;
3563 case 'c':
3564 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3565 break;
3566 case 'a':
3567 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3568 break;
3569 case 'd':
3570 opt_daemon = 1;
3571 break;
3572 case 'g':
3573 opt_tracing_group = strdup(optarg);
3574 break;
3575 case 'h':
3576 usage();
3577 exit(EXIT_FAILURE);
3578 case 'V':
3579 fprintf(stdout, "%s\n", VERSION);
3580 exit(EXIT_SUCCESS);
3581 case 'S':
3582 opt_sig_parent = 1;
3583 break;
3584 case 'E':
3585 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3586 break;
3587 case 'C':
3588 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3589 break;
3590 case 'F':
3591 snprintf(ustconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3592 break;
3593 case 'D':
3594 snprintf(ustconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3595 break;
3596 case 'q':
3597 opt_quiet = 1;
3598 break;
3599 case 'v':
3600 /* Verbose level can increase using multiple -v */
3601 opt_verbose += 1;
3602 break;
3603 case 'Z':
3604 opt_verbose_consumer += 1;
3605 break;
3606 default:
3607 /* Unknown option or other error.
3608 * Error is printed by getopt, just return */
3609 return -1;
3610 }
3611 }
3612
3613 return 0;
3614 }
3615
3616 /*
3617 * Creates the two needed socket by the daemon.
3618 * apps_sock - The communication socket for all UST apps.
3619 * client_sock - The communication of the cli tool (lttng).
3620 */
3621 static int init_daemon_socket(void)
3622 {
3623 int ret = 0;
3624 mode_t old_umask;
3625
3626 old_umask = umask(0);
3627
3628 /* Create client tool unix socket */
3629 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3630 if (client_sock < 0) {
3631 ERR("Create unix sock failed: %s", client_unix_sock_path);
3632 ret = -1;
3633 goto end;
3634 }
3635
3636 /* File permission MUST be 660 */
3637 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3638 if (ret < 0) {
3639 ERR("Set file permissions failed: %s", client_unix_sock_path);
3640 perror("chmod");
3641 goto end;
3642 }
3643
3644 /* Create the application unix socket */
3645 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3646 if (apps_sock < 0) {
3647 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3648 ret = -1;
3649 goto end;
3650 }
3651
3652 /* File permission MUST be 666 */
3653 ret = chmod(apps_unix_sock_path,
3654 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3655 if (ret < 0) {
3656 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3657 perror("chmod");
3658 goto end;
3659 }
3660
3661 end:
3662 umask(old_umask);
3663 return ret;
3664 }
3665
3666 /*
3667 * Check if the global socket is available, and if a daemon is answering at the
3668 * other side. If yes, error is returned.
3669 */
3670 static int check_existing_daemon(void)
3671 {
3672 if (access(client_unix_sock_path, F_OK) < 0 &&
3673 access(apps_unix_sock_path, F_OK) < 0) {
3674 return 0;
3675 }
3676
3677 /* Is there anybody out there ? */
3678 if (lttng_session_daemon_alive()) {
3679 return -EEXIST;
3680 } else {
3681 return 0;
3682 }
3683 }
3684
3685 /*
3686 * Set the tracing group gid onto the client socket.
3687 *
3688 * Race window between mkdir and chown is OK because we are going from more
3689 * permissive (root.root) to les permissive (root.tracing).
3690 */
3691 static int set_permissions(void)
3692 {
3693 int ret;
3694 gid_t gid;
3695
3696 gid = allowed_group();
3697 if (gid < 0) {
3698 if (is_root) {
3699 WARN("No tracing group detected");
3700 ret = 0;
3701 } else {
3702 ERR("Missing tracing group. Aborting execution.");
3703 ret = -1;
3704 }
3705 goto end;
3706 }
3707
3708 /* Set lttng run dir */
3709 ret = chown(LTTNG_RUNDIR, 0, gid);
3710 if (ret < 0) {
3711 ERR("Unable to set group on " LTTNG_RUNDIR);
3712 perror("chown");
3713 }
3714
3715 /* lttng client socket path */
3716 ret = chown(client_unix_sock_path, 0, gid);
3717 if (ret < 0) {
3718 ERR("Unable to set group on %s", client_unix_sock_path);
3719 perror("chown");
3720 }
3721
3722 /* kconsumer error socket path */
3723 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
3724 if (ret < 0) {
3725 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
3726 perror("chown");
3727 }
3728
3729 /* ustconsumer error socket path */
3730 ret = chown(ustconsumer_data.err_unix_sock_path, 0, gid);
3731 if (ret < 0) {
3732 ERR("Unable to set group on %s", ustconsumer_data.err_unix_sock_path);
3733 perror("chown");
3734 }
3735
3736 DBG("All permissions are set");
3737
3738 end:
3739 return ret;
3740 }
3741
3742 /*
3743 * Create the pipe used to wake up the kernel thread.
3744 */
3745 static int create_kernel_poll_pipe(void)
3746 {
3747 return pipe2(kernel_poll_pipe, O_CLOEXEC);
3748 }
3749
3750 /*
3751 * Create the application command pipe to wake thread_manage_apps.
3752 */
3753 static int create_apps_cmd_pipe(void)
3754 {
3755 return pipe2(apps_cmd_pipe, O_CLOEXEC);
3756 }
3757
3758 /*
3759 * Create the lttng run directory needed for all global sockets and pipe.
3760 */
3761 static int create_lttng_rundir(void)
3762 {
3763 int ret;
3764
3765 ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG );
3766 if (ret < 0) {
3767 if (errno != EEXIST) {
3768 ERR("Unable to create " LTTNG_RUNDIR);
3769 goto error;
3770 } else {
3771 ret = 0;
3772 }
3773 }
3774
3775 error:
3776 return ret;
3777 }
3778
3779 /*
3780 * Setup sockets and directory needed by the kconsumerd communication with the
3781 * session daemon.
3782 */
3783 static int set_consumer_sockets(struct consumer_data *consumer_data)
3784 {
3785 int ret;
3786 const char *path = consumer_data->type == LTTNG_CONSUMER_KERNEL ?
3787 KCONSUMERD_PATH : USTCONSUMERD_PATH;
3788
3789 if (strlen(consumer_data->err_unix_sock_path) == 0) {
3790 snprintf(consumer_data->err_unix_sock_path, PATH_MAX,
3791 consumer_data->type == LTTNG_CONSUMER_KERNEL ?
3792 KCONSUMERD_ERR_SOCK_PATH :
3793 USTCONSUMERD_ERR_SOCK_PATH);
3794 }
3795
3796 if (strlen(consumer_data->cmd_unix_sock_path) == 0) {
3797 snprintf(consumer_data->cmd_unix_sock_path, PATH_MAX,
3798 consumer_data->type == LTTNG_CONSUMER_KERNEL ?
3799 KCONSUMERD_CMD_SOCK_PATH :
3800 USTCONSUMERD_CMD_SOCK_PATH);
3801 }
3802
3803 ret = mkdir(path, S_IRWXU | S_IRWXG);
3804 if (ret < 0) {
3805 if (errno != EEXIST) {
3806 ERR("Failed to create %s", path);
3807 goto error;
3808 }
3809 ret = 0;
3810 }
3811
3812 /* Create the kconsumerd error unix socket */
3813 consumer_data->err_sock =
3814 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
3815 if (consumer_data->err_sock < 0) {
3816 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
3817 ret = -1;
3818 goto error;
3819 }
3820
3821 /* File permission MUST be 660 */
3822 ret = chmod(consumer_data->err_unix_sock_path,
3823 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3824 if (ret < 0) {
3825 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
3826 perror("chmod");
3827 goto error;
3828 }
3829
3830 error:
3831 return ret;
3832 }
3833
3834 /*
3835 * Signal handler for the daemon
3836 *
3837 * Simply stop all worker threads, leaving main() return gracefully after
3838 * joining all threads and calling cleanup().
3839 */
3840 static void sighandler(int sig)
3841 {
3842 switch (sig) {
3843 case SIGPIPE:
3844 DBG("SIGPIPE catched");
3845 return;
3846 case SIGINT:
3847 DBG("SIGINT catched");
3848 stop_threads();
3849 break;
3850 case SIGTERM:
3851 DBG("SIGTERM catched");
3852 stop_threads();
3853 break;
3854 default:
3855 break;
3856 }
3857 }
3858
3859 /*
3860 * Setup signal handler for :
3861 * SIGINT, SIGTERM, SIGPIPE
3862 */
3863 static int set_signal_handler(void)
3864 {
3865 int ret = 0;
3866 struct sigaction sa;
3867 sigset_t sigset;
3868
3869 if ((ret = sigemptyset(&sigset)) < 0) {
3870 perror("sigemptyset");
3871 return ret;
3872 }
3873
3874 sa.sa_handler = sighandler;
3875 sa.sa_mask = sigset;
3876 sa.sa_flags = 0;
3877 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
3878 perror("sigaction");
3879 return ret;
3880 }
3881
3882 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
3883 perror("sigaction");
3884 return ret;
3885 }
3886
3887 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
3888 perror("sigaction");
3889 return ret;
3890 }
3891
3892 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3893
3894 return ret;
3895 }
3896
3897 /*
3898 * Set open files limit to unlimited. This daemon can open a large number of
3899 * file descriptors in order to consumer multiple kernel traces.
3900 */
3901 static void set_ulimit(void)
3902 {
3903 int ret;
3904 struct rlimit lim;
3905
3906 /* The kernel does not allowed an infinite limit for open files */
3907 lim.rlim_cur = 65535;
3908 lim.rlim_max = 65535;
3909
3910 ret = setrlimit(RLIMIT_NOFILE, &lim);
3911 if (ret < 0) {
3912 perror("failed to set open files limit");
3913 }
3914 }
3915
3916 /*
3917 * main
3918 */
3919 int main(int argc, char **argv)
3920 {
3921 int ret = 0;
3922 void *status;
3923 const char *home_path;
3924
3925 /* Create thread quit pipe */
3926 if ((ret = init_thread_quit_pipe()) < 0) {
3927 goto error;
3928 }
3929
3930 /* Parse arguments */
3931 progname = argv[0];
3932 if ((ret = parse_args(argc, argv) < 0)) {
3933 goto error;
3934 }
3935
3936 /* Daemonize */
3937 if (opt_daemon) {
3938 ret = daemon(0, 0);
3939 if (ret < 0) {
3940 perror("daemon");
3941 goto error;
3942 }
3943 }
3944
3945 /* Check if daemon is UID = 0 */
3946 is_root = !getuid();
3947
3948 if (is_root) {
3949 ret = create_lttng_rundir();
3950 if (ret < 0) {
3951 goto error;
3952 }
3953
3954 if (strlen(apps_unix_sock_path) == 0) {
3955 snprintf(apps_unix_sock_path, PATH_MAX,
3956 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
3957 }
3958
3959 if (strlen(client_unix_sock_path) == 0) {
3960 snprintf(client_unix_sock_path, PATH_MAX,
3961 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
3962 }
3963
3964 /* Set global SHM for ust */
3965 if (strlen(wait_shm_path) == 0) {
3966 snprintf(wait_shm_path, PATH_MAX,
3967 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
3968 }
3969 } else {
3970 home_path = get_home_dir();
3971 if (home_path == NULL) {
3972 /* TODO: Add --socket PATH option */
3973 ERR("Can't get HOME directory for sockets creation.");
3974 ret = -EPERM;
3975 goto error;
3976 }
3977
3978 if (strlen(apps_unix_sock_path) == 0) {
3979 snprintf(apps_unix_sock_path, PATH_MAX,
3980 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
3981 }
3982
3983 /* Set the cli tool unix socket path */
3984 if (strlen(client_unix_sock_path) == 0) {
3985 snprintf(client_unix_sock_path, PATH_MAX,
3986 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
3987 }
3988
3989 /* Set global SHM for ust */
3990 if (strlen(wait_shm_path) == 0) {
3991 snprintf(wait_shm_path, PATH_MAX,
3992 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
3993 }
3994 }
3995
3996 DBG("Client socket path %s", client_unix_sock_path);
3997 DBG("Application socket path %s", apps_unix_sock_path);
3998
3999 /*
4000 * See if daemon already exist.
4001 */
4002 if ((ret = check_existing_daemon()) < 0) {
4003 ERR("Already running daemon.\n");
4004 /*
4005 * We do not goto exit because we must not cleanup()
4006 * because a daemon is already running.
4007 */
4008 goto error;
4009 }
4010
4011 /* After this point, we can safely call cleanup() with "goto exit" */
4012
4013 /*
4014 * These actions must be executed as root. We do that *after* setting up
4015 * the sockets path because we MUST make the check for another daemon using
4016 * those paths *before* trying to set the kernel consumer sockets and init
4017 * kernel tracer.
4018 */
4019 if (is_root) {
4020 ret = set_consumer_sockets(&kconsumer_data);
4021 if (ret < 0) {
4022 goto exit;
4023 }
4024 ret = set_consumer_sockets(&ustconsumer_data);
4025 if (ret < 0) {
4026 goto exit;
4027 }
4028 /* Setup kernel tracer */
4029 init_kernel_tracer();
4030
4031 /* Set ulimit for open files */
4032 set_ulimit();
4033 }
4034
4035 if ((ret = set_signal_handler()) < 0) {
4036 goto exit;
4037 }
4038
4039 /* Setup the needed unix socket */
4040 if ((ret = init_daemon_socket()) < 0) {
4041 goto exit;
4042 }
4043
4044 /* Set credentials to socket */
4045 if (is_root && ((ret = set_permissions()) < 0)) {
4046 goto exit;
4047 }
4048
4049 /* Get parent pid if -S, --sig-parent is specified. */
4050 if (opt_sig_parent) {
4051 ppid = getppid();
4052 }
4053
4054 /* Setup the kernel pipe for waking up the kernel thread */
4055 if ((ret = create_kernel_poll_pipe()) < 0) {
4056 goto exit;
4057 }
4058
4059 /* Setup the thread apps communication pipe. */
4060 if ((ret = create_apps_cmd_pipe()) < 0) {
4061 goto exit;
4062 }
4063
4064 /* Init UST command queue. */
4065 cds_wfq_init(&ust_cmd_queue.queue);
4066
4067 /*
4068 * Get session list pointer. This pointer MUST NOT be free(). This list is
4069 * statically declared in session.c
4070 */
4071 session_list_ptr = session_get_list();
4072
4073 /* Set up max poll set size */
4074 lttng_poll_set_max_size();
4075
4076 /* Create thread to manage the client socket */
4077 ret = pthread_create(&client_thread, NULL,
4078 thread_manage_clients, (void *) NULL);
4079 if (ret != 0) {
4080 perror("pthread_create clients");
4081 goto exit_client;
4082 }
4083
4084 /* Create thread to dispatch registration */
4085 ret = pthread_create(&dispatch_thread, NULL,
4086 thread_dispatch_ust_registration, (void *) NULL);
4087 if (ret != 0) {
4088 perror("pthread_create dispatch");
4089 goto exit_dispatch;
4090 }
4091
4092 /* Create thread to manage application registration. */
4093 ret = pthread_create(&reg_apps_thread, NULL,
4094 thread_registration_apps, (void *) NULL);
4095 if (ret != 0) {
4096 perror("pthread_create registration");
4097 goto exit_reg_apps;
4098 }
4099
4100 /* Create thread to manage application socket */
4101 ret = pthread_create(&apps_thread, NULL,
4102 thread_manage_apps, (void *) NULL);
4103 if (ret != 0) {
4104 perror("pthread_create apps");
4105 goto exit_apps;
4106 }
4107
4108 /* Create kernel thread to manage kernel event */
4109 ret = pthread_create(&kernel_thread, NULL,
4110 thread_manage_kernel, (void *) NULL);
4111 if (ret != 0) {
4112 perror("pthread_create kernel");
4113 goto exit_kernel;
4114 }
4115
4116 ret = pthread_join(kernel_thread, &status);
4117 if (ret != 0) {
4118 perror("pthread_join");
4119 goto error; /* join error, exit without cleanup */
4120 }
4121
4122 exit_kernel:
4123 ret = pthread_join(apps_thread, &status);
4124 if (ret != 0) {
4125 perror("pthread_join");
4126 goto error; /* join error, exit without cleanup */
4127 }
4128
4129 exit_apps:
4130 ret = pthread_join(reg_apps_thread, &status);
4131 if (ret != 0) {
4132 perror("pthread_join");
4133 goto error; /* join error, exit without cleanup */
4134 }
4135
4136 exit_reg_apps:
4137 ret = pthread_join(dispatch_thread, &status);
4138 if (ret != 0) {
4139 perror("pthread_join");
4140 goto error; /* join error, exit without cleanup */
4141 }
4142
4143 exit_dispatch:
4144 ret = pthread_join(client_thread, &status);
4145 if (ret != 0) {
4146 perror("pthread_join");
4147 goto error; /* join error, exit without cleanup */
4148 }
4149
4150 ret = join_consumer_thread(&kconsumer_data);
4151 if (ret != 0) {
4152 perror("join_consumer");
4153 goto error; /* join error, exit without cleanup */
4154 }
4155
4156 exit_client:
4157 exit:
4158 /*
4159 * cleanup() is called when no other thread is running.
4160 */
4161 cleanup();
4162 if (!ret)
4163 exit(EXIT_SUCCESS);
4164 error:
4165 exit(EXIT_FAILURE);
4166 }
LTTng 2.0 tools and control repository
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