7dd652abc38b62994d9ed9c1c9df8a663fedabca
[lttng-tools.git] / src / bin / lttng-sessiond / main.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #define _GNU_SOURCE
20 #include <getopt.h>
21 #include <grp.h>
22 #include <limits.h>
23 #include <pthread.h>
24 #include <signal.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <sys/mman.h>
29 #include <sys/mount.h>
30 #include <sys/resource.h>
31 #include <sys/socket.h>
32 #include <sys/stat.h>
33 #include <sys/types.h>
34 #include <sys/wait.h>
35 #include <urcu/uatomic.h>
36 #include <unistd.h>
37 #include <config.h>
38
39 #include <common/common.h>
40 #include <common/compat/poll.h>
41 #include <common/compat/socket.h>
42 #include <common/defaults.h>
43 #include <common/kernel-consumer/kernel-consumer.h>
44 #include <common/futex.h>
45 #include <common/relayd/relayd.h>
46 #include <common/utils.h>
47
48 #include "lttng-sessiond.h"
49 #include "channel.h"
50 #include "cmd.h"
51 #include "consumer.h"
52 #include "context.h"
53 #include "event.h"
54 #include "kernel.h"
55 #include "kernel-consumer.h"
56 #include "modprobe.h"
57 #include "shm.h"
58 #include "ust-ctl.h"
59 #include "ust-consumer.h"
60 #include "utils.h"
61 #include "fd-limit.h"
62 #include "filter.h"
63 #include "health.h"
64 #include "testpoint.h"
65
66 #define CONSUMERD_FILE "lttng-consumerd"
67
68 /* Const values */
69 const char default_home_dir[] = DEFAULT_HOME_DIR;
70 const char default_tracing_group[] = DEFAULT_TRACING_GROUP;
71 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
72 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
73
74 const char *progname;
75 const char *opt_tracing_group;
76 static int opt_sig_parent;
77 static int opt_verbose_consumer;
78 static int opt_daemon;
79 static int opt_no_kernel;
80 static int is_root; /* Set to 1 if the daemon is running as root */
81 static pid_t ppid; /* Parent PID for --sig-parent option */
82 static char *rundir;
83
84 /*
85 * Consumer daemon specific control data. Every value not initialized here is
86 * set to 0 by the static definition.
87 */
88 static struct consumer_data kconsumer_data = {
89 .type = LTTNG_CONSUMER_KERNEL,
90 .err_unix_sock_path = DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
91 .cmd_unix_sock_path = DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
92 .err_sock = -1,
93 .cmd_sock = -1,
94 .pid_mutex = PTHREAD_MUTEX_INITIALIZER,
95 .lock = PTHREAD_MUTEX_INITIALIZER,
96 .cond = PTHREAD_COND_INITIALIZER,
97 .cond_mutex = PTHREAD_MUTEX_INITIALIZER,
98 };
99 static struct consumer_data ustconsumer64_data = {
100 .type = LTTNG_CONSUMER64_UST,
101 .err_unix_sock_path = DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
102 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
103 .err_sock = -1,
104 .cmd_sock = -1,
105 .pid_mutex = PTHREAD_MUTEX_INITIALIZER,
106 .lock = PTHREAD_MUTEX_INITIALIZER,
107 .cond = PTHREAD_COND_INITIALIZER,
108 .cond_mutex = PTHREAD_MUTEX_INITIALIZER,
109 };
110 static struct consumer_data ustconsumer32_data = {
111 .type = LTTNG_CONSUMER32_UST,
112 .err_unix_sock_path = DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
113 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
114 .err_sock = -1,
115 .cmd_sock = -1,
116 .pid_mutex = PTHREAD_MUTEX_INITIALIZER,
117 .lock = PTHREAD_MUTEX_INITIALIZER,
118 .cond = PTHREAD_COND_INITIALIZER,
119 .cond_mutex = PTHREAD_MUTEX_INITIALIZER,
120 };
121
122 /* Shared between threads */
123 static int dispatch_thread_exit;
124
125 /* Global application Unix socket path */
126 static char apps_unix_sock_path[PATH_MAX];
127 /* Global client Unix socket path */
128 static char client_unix_sock_path[PATH_MAX];
129 /* global wait shm path for UST */
130 static char wait_shm_path[PATH_MAX];
131 /* Global health check unix path */
132 static char health_unix_sock_path[PATH_MAX];
133
134 /* Sockets and FDs */
135 static int client_sock = -1;
136 static int apps_sock = -1;
137 int kernel_tracer_fd = -1;
138 static int kernel_poll_pipe[2] = { -1, -1 };
139
140 /*
141 * Quit pipe for all threads. This permits a single cancellation point
142 * for all threads when receiving an event on the pipe.
143 */
144 static int thread_quit_pipe[2] = { -1, -1 };
145
146 /*
147 * This pipe is used to inform the thread managing application communication
148 * that a command is queued and ready to be processed.
149 */
150 static int apps_cmd_pipe[2] = { -1, -1 };
151
152 /* Pthread, Mutexes and Semaphores */
153 static pthread_t apps_thread;
154 static pthread_t reg_apps_thread;
155 static pthread_t client_thread;
156 static pthread_t kernel_thread;
157 static pthread_t dispatch_thread;
158 static pthread_t health_thread;
159
160 /*
161 * UST registration command queue. This queue is tied with a futex and uses a N
162 * wakers / 1 waiter implemented and detailed in futex.c/.h
163 *
164 * The thread_manage_apps and thread_dispatch_ust_registration interact with
165 * this queue and the wait/wake scheme.
166 */
167 static struct ust_cmd_queue ust_cmd_queue;
168
169 /*
170 * Pointer initialized before thread creation.
171 *
172 * This points to the tracing session list containing the session count and a
173 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
174 * MUST NOT be taken if you call a public function in session.c.
175 *
176 * The lock is nested inside the structure: session_list_ptr->lock. Please use
177 * session_lock_list and session_unlock_list for lock acquisition.
178 */
179 static struct ltt_session_list *session_list_ptr;
180
181 int ust_consumerd64_fd = -1;
182 int ust_consumerd32_fd = -1;
183
184 static const char *consumerd32_bin = CONFIG_CONSUMERD32_BIN;
185 static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
186 static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
187 static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
188
189 static const char *module_proc_lttng = "/proc/lttng";
190
191 /*
192 * Consumer daemon state which is changed when spawning it, killing it or in
193 * case of a fatal error.
194 */
195 enum consumerd_state {
196 CONSUMER_STARTED = 1,
197 CONSUMER_STOPPED = 2,
198 CONSUMER_ERROR = 3,
199 };
200
201 /*
202 * This consumer daemon state is used to validate if a client command will be
203 * able to reach the consumer. If not, the client is informed. For instance,
204 * doing a "lttng start" when the consumer state is set to ERROR will return an
205 * error to the client.
206 *
207 * The following example shows a possible race condition of this scheme:
208 *
209 * consumer thread error happens
210 * client cmd arrives
211 * client cmd checks state -> still OK
212 * consumer thread exit, sets error
213 * client cmd try to talk to consumer
214 * ...
215 *
216 * However, since the consumer is a different daemon, we have no way of making
217 * sure the command will reach it safely even with this state flag. This is why
218 * we consider that up to the state validation during command processing, the
219 * command is safe. After that, we can not guarantee the correctness of the
220 * client request vis-a-vis the consumer.
221 */
222 static enum consumerd_state ust_consumerd_state;
223 static enum consumerd_state kernel_consumerd_state;
224
225 /* Used for the health monitoring of the session daemon. See health.h */
226 struct health_state health_thread_cmd;
227 struct health_state health_thread_app_manage;
228 struct health_state health_thread_app_reg;
229 struct health_state health_thread_kernel;
230
231 /*
232 * Socket timeout for receiving and sending in seconds.
233 */
234 static int app_socket_timeout;
235
236 static
237 void setup_consumerd_path(void)
238 {
239 const char *bin, *libdir;
240
241 /*
242 * Allow INSTALL_BIN_PATH to be used as a target path for the
243 * native architecture size consumer if CONFIG_CONSUMER*_PATH
244 * has not been defined.
245 */
246 #if (CAA_BITS_PER_LONG == 32)
247 if (!consumerd32_bin[0]) {
248 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
249 }
250 if (!consumerd32_libdir[0]) {
251 consumerd32_libdir = INSTALL_LIB_PATH;
252 }
253 #elif (CAA_BITS_PER_LONG == 64)
254 if (!consumerd64_bin[0]) {
255 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
256 }
257 if (!consumerd64_libdir[0]) {
258 consumerd64_libdir = INSTALL_LIB_PATH;
259 }
260 #else
261 #error "Unknown bitness"
262 #endif
263
264 /*
265 * runtime env. var. overrides the build default.
266 */
267 bin = getenv("LTTNG_CONSUMERD32_BIN");
268 if (bin) {
269 consumerd32_bin = bin;
270 }
271 bin = getenv("LTTNG_CONSUMERD64_BIN");
272 if (bin) {
273 consumerd64_bin = bin;
274 }
275 libdir = getenv("LTTNG_CONSUMERD32_LIBDIR");
276 if (libdir) {
277 consumerd32_libdir = libdir;
278 }
279 libdir = getenv("LTTNG_CONSUMERD64_LIBDIR");
280 if (libdir) {
281 consumerd64_libdir = libdir;
282 }
283 }
284
285 /*
286 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
287 */
288 static int create_thread_poll_set(struct lttng_poll_event *events,
289 unsigned int size)
290 {
291 int ret;
292
293 if (events == NULL || size == 0) {
294 ret = -1;
295 goto error;
296 }
297
298 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
299 if (ret < 0) {
300 goto error;
301 }
302
303 /* Add quit pipe */
304 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
305 if (ret < 0) {
306 goto error;
307 }
308
309 return 0;
310
311 error:
312 return ret;
313 }
314
315 /*
316 * Check if the thread quit pipe was triggered.
317 *
318 * Return 1 if it was triggered else 0;
319 */
320 static int check_thread_quit_pipe(int fd, uint32_t events)
321 {
322 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
323 return 1;
324 }
325
326 return 0;
327 }
328
329 /*
330 * Return group ID of the tracing group or -1 if not found.
331 */
332 static gid_t allowed_group(void)
333 {
334 struct group *grp;
335
336 if (opt_tracing_group) {
337 grp = getgrnam(opt_tracing_group);
338 } else {
339 grp = getgrnam(default_tracing_group);
340 }
341 if (!grp) {
342 return -1;
343 } else {
344 return grp->gr_gid;
345 }
346 }
347
348 /*
349 * Init thread quit pipe.
350 *
351 * Return -1 on error or 0 if all pipes are created.
352 */
353 static int init_thread_quit_pipe(void)
354 {
355 int ret, i;
356
357 ret = pipe(thread_quit_pipe);
358 if (ret < 0) {
359 PERROR("thread quit pipe");
360 goto error;
361 }
362
363 for (i = 0; i < 2; i++) {
364 ret = fcntl(thread_quit_pipe[i], F_SETFD, FD_CLOEXEC);
365 if (ret < 0) {
366 PERROR("fcntl");
367 goto error;
368 }
369 }
370
371 error:
372 return ret;
373 }
374
375 /*
376 * Stop all threads by closing the thread quit pipe.
377 */
378 static void stop_threads(void)
379 {
380 int ret;
381
382 /* Stopping all threads */
383 DBG("Terminating all threads");
384 ret = notify_thread_pipe(thread_quit_pipe[1]);
385 if (ret < 0) {
386 ERR("write error on thread quit pipe");
387 }
388
389 /* Dispatch thread */
390 CMM_STORE_SHARED(dispatch_thread_exit, 1);
391 futex_nto1_wake(&ust_cmd_queue.futex);
392 }
393
394 /*
395 * Cleanup the daemon
396 */
397 static void cleanup(void)
398 {
399 int ret;
400 char *cmd = NULL;
401 struct ltt_session *sess, *stmp;
402
403 DBG("Cleaning up");
404
405 /* First thing first, stop all threads */
406 utils_close_pipe(thread_quit_pipe);
407
408 DBG("Removing %s directory", rundir);
409 ret = asprintf(&cmd, "rm -rf %s", rundir);
410 if (ret < 0) {
411 ERR("asprintf failed. Something is really wrong!");
412 }
413
414 /* Remove lttng run directory */
415 ret = system(cmd);
416 if (ret < 0) {
417 ERR("Unable to clean %s", rundir);
418 }
419 free(cmd);
420 free(rundir);
421
422 DBG("Cleaning up all sessions");
423
424 /* Destroy session list mutex */
425 if (session_list_ptr != NULL) {
426 pthread_mutex_destroy(&session_list_ptr->lock);
427
428 /* Cleanup ALL session */
429 cds_list_for_each_entry_safe(sess, stmp,
430 &session_list_ptr->head, list) {
431 cmd_destroy_session(sess, kernel_poll_pipe[1]);
432 }
433 }
434
435 DBG("Closing all UST sockets");
436 ust_app_clean_list();
437
438 if (is_root && !opt_no_kernel) {
439 DBG2("Closing kernel fd");
440 if (kernel_tracer_fd >= 0) {
441 ret = close(kernel_tracer_fd);
442 if (ret) {
443 PERROR("close");
444 }
445 }
446 DBG("Unloading kernel modules");
447 modprobe_remove_lttng_all();
448 }
449
450 /* <fun> */
451 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
452 "Matthew, BEET driven development works!%c[%dm",
453 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
454 /* </fun> */
455 }
456
457 /*
458 * Send data on a unix socket using the liblttsessiondcomm API.
459 *
460 * Return lttcomm error code.
461 */
462 static int send_unix_sock(int sock, void *buf, size_t len)
463 {
464 /* Check valid length */
465 if (len <= 0) {
466 return -1;
467 }
468
469 return lttcomm_send_unix_sock(sock, buf, len);
470 }
471
472 /*
473 * Free memory of a command context structure.
474 */
475 static void clean_command_ctx(struct command_ctx **cmd_ctx)
476 {
477 DBG("Clean command context structure");
478 if (*cmd_ctx) {
479 if ((*cmd_ctx)->llm) {
480 free((*cmd_ctx)->llm);
481 }
482 if ((*cmd_ctx)->lsm) {
483 free((*cmd_ctx)->lsm);
484 }
485 free(*cmd_ctx);
486 *cmd_ctx = NULL;
487 }
488 }
489
490 /*
491 * Notify UST applications using the shm mmap futex.
492 */
493 static int notify_ust_apps(int active)
494 {
495 char *wait_shm_mmap;
496
497 DBG("Notifying applications of session daemon state: %d", active);
498
499 /* See shm.c for this call implying mmap, shm and futex calls */
500 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
501 if (wait_shm_mmap == NULL) {
502 goto error;
503 }
504
505 /* Wake waiting process */
506 futex_wait_update((int32_t *) wait_shm_mmap, active);
507
508 /* Apps notified successfully */
509 return 0;
510
511 error:
512 return -1;
513 }
514
515 /*
516 * Setup the outgoing data buffer for the response (llm) by allocating the
517 * right amount of memory and copying the original information from the lsm
518 * structure.
519 *
520 * Return total size of the buffer pointed by buf.
521 */
522 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
523 {
524 int ret, buf_size;
525
526 buf_size = size;
527
528 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
529 if (cmd_ctx->llm == NULL) {
530 PERROR("zmalloc");
531 ret = -ENOMEM;
532 goto error;
533 }
534
535 /* Copy common data */
536 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
537 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
538
539 cmd_ctx->llm->data_size = size;
540 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
541
542 return buf_size;
543
544 error:
545 return ret;
546 }
547
548 /*
549 * Update the kernel poll set of all channel fd available over all tracing
550 * session. Add the wakeup pipe at the end of the set.
551 */
552 static int update_kernel_poll(struct lttng_poll_event *events)
553 {
554 int ret;
555 struct ltt_session *session;
556 struct ltt_kernel_channel *channel;
557
558 DBG("Updating kernel poll set");
559
560 session_lock_list();
561 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
562 session_lock(session);
563 if (session->kernel_session == NULL) {
564 session_unlock(session);
565 continue;
566 }
567
568 cds_list_for_each_entry(channel,
569 &session->kernel_session->channel_list.head, list) {
570 /* Add channel fd to the kernel poll set */
571 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
572 if (ret < 0) {
573 session_unlock(session);
574 goto error;
575 }
576 DBG("Channel fd %d added to kernel set", channel->fd);
577 }
578 session_unlock(session);
579 }
580 session_unlock_list();
581
582 return 0;
583
584 error:
585 session_unlock_list();
586 return -1;
587 }
588
589 /*
590 * Find the channel fd from 'fd' over all tracing session. When found, check
591 * for new channel stream and send those stream fds to the kernel consumer.
592 *
593 * Useful for CPU hotplug feature.
594 */
595 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
596 {
597 int ret = 0;
598 struct ltt_session *session;
599 struct ltt_kernel_session *ksess;
600 struct ltt_kernel_channel *channel;
601
602 DBG("Updating kernel streams for channel fd %d", fd);
603
604 session_lock_list();
605 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
606 session_lock(session);
607 if (session->kernel_session == NULL) {
608 session_unlock(session);
609 continue;
610 }
611 ksess = session->kernel_session;
612
613 cds_list_for_each_entry(channel, &ksess->channel_list.head, list) {
614 if (channel->fd == fd) {
615 DBG("Channel found, updating kernel streams");
616 ret = kernel_open_channel_stream(channel);
617 if (ret < 0) {
618 goto error;
619 }
620
621 /*
622 * Have we already sent fds to the consumer? If yes, it means
623 * that tracing is started so it is safe to send our updated
624 * stream fds.
625 */
626 if (ksess->consumer_fds_sent == 1 && ksess->consumer != NULL) {
627 struct lttng_ht_iter iter;
628 struct consumer_socket *socket;
629
630
631 cds_lfht_for_each_entry(ksess->consumer->socks->ht,
632 &iter.iter, socket, node.node) {
633 /* Code flow error */
634 assert(socket->fd >= 0);
635
636 pthread_mutex_lock(socket->lock);
637 ret = kernel_consumer_send_channel_stream(socket->fd,
638 channel, ksess);
639 pthread_mutex_unlock(socket->lock);
640 if (ret < 0) {
641 goto error;
642 }
643 }
644 }
645 goto error;
646 }
647 }
648 session_unlock(session);
649 }
650 session_unlock_list();
651 return ret;
652
653 error:
654 session_unlock(session);
655 session_unlock_list();
656 return ret;
657 }
658
659 /*
660 * For each tracing session, update newly registered apps.
661 */
662 static void update_ust_app(int app_sock)
663 {
664 struct ltt_session *sess, *stmp;
665
666 session_lock_list();
667
668 /* For all tracing session(s) */
669 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
670 session_lock(sess);
671 if (sess->ust_session) {
672 ust_app_global_update(sess->ust_session, app_sock);
673 }
674 session_unlock(sess);
675 }
676
677 session_unlock_list();
678 }
679
680 /*
681 * This thread manage event coming from the kernel.
682 *
683 * Features supported in this thread:
684 * -) CPU Hotplug
685 */
686 static void *thread_manage_kernel(void *data)
687 {
688 int ret, i, pollfd, update_poll_flag = 1, err = -1;
689 uint32_t revents, nb_fd;
690 char tmp;
691 struct lttng_poll_event events;
692
693 DBG("Thread manage kernel started");
694
695 testpoint(thread_manage_kernel);
696
697 health_code_update(&health_thread_kernel);
698
699 testpoint(thread_manage_kernel_before_loop);
700
701 ret = create_thread_poll_set(&events, 2);
702 if (ret < 0) {
703 goto error_poll_create;
704 }
705
706 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
707 if (ret < 0) {
708 goto error;
709 }
710
711 while (1) {
712 health_code_update(&health_thread_kernel);
713
714 if (update_poll_flag == 1) {
715 /*
716 * Reset number of fd in the poll set. Always 2 since there is the thread
717 * quit pipe and the kernel pipe.
718 */
719 events.nb_fd = 2;
720
721 ret = update_kernel_poll(&events);
722 if (ret < 0) {
723 goto error;
724 }
725 update_poll_flag = 0;
726 }
727
728 nb_fd = LTTNG_POLL_GETNB(&events);
729
730 DBG("Thread kernel polling on %d fds", nb_fd);
731
732 /* Zeroed the poll events */
733 lttng_poll_reset(&events);
734
735 /* Poll infinite value of time */
736 restart:
737 health_poll_update(&health_thread_kernel);
738 ret = lttng_poll_wait(&events, -1);
739 health_poll_update(&health_thread_kernel);
740 if (ret < 0) {
741 /*
742 * Restart interrupted system call.
743 */
744 if (errno == EINTR) {
745 goto restart;
746 }
747 goto error;
748 } else if (ret == 0) {
749 /* Should not happen since timeout is infinite */
750 ERR("Return value of poll is 0 with an infinite timeout.\n"
751 "This should not have happened! Continuing...");
752 continue;
753 }
754
755 for (i = 0; i < nb_fd; i++) {
756 /* Fetch once the poll data */
757 revents = LTTNG_POLL_GETEV(&events, i);
758 pollfd = LTTNG_POLL_GETFD(&events, i);
759
760 health_code_update(&health_thread_kernel);
761
762 /* Thread quit pipe has been closed. Killing thread. */
763 ret = check_thread_quit_pipe(pollfd, revents);
764 if (ret) {
765 err = 0;
766 goto exit;
767 }
768
769 /* Check for data on kernel pipe */
770 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
771 ret = read(kernel_poll_pipe[0], &tmp, 1);
772 update_poll_flag = 1;
773 continue;
774 } else {
775 /*
776 * New CPU detected by the kernel. Adding kernel stream to
777 * kernel session and updating the kernel consumer
778 */
779 if (revents & LPOLLIN) {
780 ret = update_kernel_stream(&kconsumer_data, pollfd);
781 if (ret < 0) {
782 continue;
783 }
784 break;
785 /*
786 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
787 * and unregister kernel stream at this point.
788 */
789 }
790 }
791 }
792 }
793
794 exit:
795 error:
796 lttng_poll_clean(&events);
797 error_poll_create:
798 utils_close_pipe(kernel_poll_pipe);
799 kernel_poll_pipe[0] = kernel_poll_pipe[1] = -1;
800 if (err) {
801 health_error(&health_thread_kernel);
802 ERR("Health error occurred in %s", __func__);
803 WARN("Kernel thread died unexpectedly. "
804 "Kernel tracing can continue but CPU hotplug is disabled.");
805 }
806 health_exit(&health_thread_kernel);
807 DBG("Kernel thread dying");
808 return NULL;
809 }
810
811 /*
812 * Signal pthread condition of the consumer data that the thread.
813 */
814 static void signal_consumer_condition(struct consumer_data *data, int state)
815 {
816 pthread_mutex_lock(&data->cond_mutex);
817
818 /*
819 * The state is set before signaling. It can be any value, it's the waiter
820 * job to correctly interpret this condition variable associated to the
821 * consumer pthread_cond.
822 *
823 * A value of 0 means that the corresponding thread of the consumer data
824 * was not started. 1 indicates that the thread has started and is ready
825 * for action. A negative value means that there was an error during the
826 * thread bootstrap.
827 */
828 data->consumer_thread_is_ready = state;
829 (void) pthread_cond_signal(&data->cond);
830
831 pthread_mutex_unlock(&data->cond_mutex);
832 }
833
834 /*
835 * This thread manage the consumer error sent back to the session daemon.
836 */
837 static void *thread_manage_consumer(void *data)
838 {
839 int sock = -1, i, ret, pollfd, err = -1;
840 uint32_t revents, nb_fd;
841 enum lttcomm_return_code code;
842 struct lttng_poll_event events;
843 struct consumer_data *consumer_data = data;
844
845 DBG("[thread] Manage consumer started");
846
847 /*
848 * Since the consumer thread can be spawned at any moment in time, we init
849 * the health to a poll status (1, which is a valid health over time).
850 * When the thread starts, we update here the health to a "code" path being
851 * an even value so this thread, when reaching a poll wait, does not
852 * trigger an error with an even value.
853 *
854 * Here is the use case we avoid.
855 *
856 * +1: the first poll update during initialization (main())
857 * +2 * x: multiple code update once in this thread.
858 * +1: poll wait in this thread (being a good health state).
859 * == even number which after the wait period shows as a bad health.
860 *
861 * In a nutshell, the following poll update to the health state brings back
862 * the state to an even value meaning a code path.
863 */
864 health_poll_update(&consumer_data->health);
865
866 /*
867 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
868 * Nothing more will be added to this poll set.
869 */
870 ret = create_thread_poll_set(&events, 2);
871 if (ret < 0) {
872 goto error_poll;
873 }
874
875 /*
876 * The error socket here is already in a listening state which was done
877 * just before spawning this thread to avoid a race between the consumer
878 * daemon exec trying to connect and the listen() call.
879 */
880 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
881 if (ret < 0) {
882 goto error;
883 }
884
885 nb_fd = LTTNG_POLL_GETNB(&events);
886
887 health_code_update(&consumer_data->health);
888
889 /* Inifinite blocking call, waiting for transmission */
890 restart:
891 health_poll_update(&consumer_data->health);
892
893 testpoint(thread_manage_consumer);
894
895 ret = lttng_poll_wait(&events, -1);
896 health_poll_update(&consumer_data->health);
897 if (ret < 0) {
898 /*
899 * Restart interrupted system call.
900 */
901 if (errno == EINTR) {
902 goto restart;
903 }
904 goto error;
905 }
906
907 for (i = 0; i < nb_fd; i++) {
908 /* Fetch once the poll data */
909 revents = LTTNG_POLL_GETEV(&events, i);
910 pollfd = LTTNG_POLL_GETFD(&events, i);
911
912 health_code_update(&consumer_data->health);
913
914 /* Thread quit pipe has been closed. Killing thread. */
915 ret = check_thread_quit_pipe(pollfd, revents);
916 if (ret) {
917 err = 0;
918 goto exit;
919 }
920
921 /* Event on the registration socket */
922 if (pollfd == consumer_data->err_sock) {
923 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
924 ERR("consumer err socket poll error");
925 goto error;
926 }
927 }
928 }
929
930 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
931 if (sock < 0) {
932 goto error;
933 }
934
935 /*
936 * Set the CLOEXEC flag. Return code is useless because either way, the
937 * show must go on.
938 */
939 (void) utils_set_fd_cloexec(sock);
940
941 health_code_update(&consumer_data->health);
942
943 DBG2("Receiving code from consumer err_sock");
944
945 /* Getting status code from kconsumerd */
946 ret = lttcomm_recv_unix_sock(sock, &code,
947 sizeof(enum lttcomm_return_code));
948 if (ret <= 0) {
949 goto error;
950 }
951
952 health_code_update(&consumer_data->health);
953
954 if (code == LTTCOMM_CONSUMERD_COMMAND_SOCK_READY) {
955 consumer_data->cmd_sock =
956 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
957 if (consumer_data->cmd_sock < 0) {
958 /* On error, signal condition and quit. */
959 signal_consumer_condition(consumer_data, -1);
960 PERROR("consumer connect");
961 goto error;
962 }
963 signal_consumer_condition(consumer_data, 1);
964 DBG("Consumer command socket ready");
965 } else {
966 ERR("consumer error when waiting for SOCK_READY : %s",
967 lttcomm_get_readable_code(-code));
968 goto error;
969 }
970
971 /* Remove the kconsumerd error sock since we've established a connexion */
972 ret = lttng_poll_del(&events, consumer_data->err_sock);
973 if (ret < 0) {
974 goto error;
975 }
976
977 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
978 if (ret < 0) {
979 goto error;
980 }
981
982 health_code_update(&consumer_data->health);
983
984 /* Update number of fd */
985 nb_fd = LTTNG_POLL_GETNB(&events);
986
987 /* Inifinite blocking call, waiting for transmission */
988 restart_poll:
989 health_poll_update(&consumer_data->health);
990 ret = lttng_poll_wait(&events, -1);
991 health_poll_update(&consumer_data->health);
992 if (ret < 0) {
993 /*
994 * Restart interrupted system call.
995 */
996 if (errno == EINTR) {
997 goto restart_poll;
998 }
999 goto error;
1000 }
1001
1002 for (i = 0; i < nb_fd; i++) {
1003 /* Fetch once the poll data */
1004 revents = LTTNG_POLL_GETEV(&events, i);
1005 pollfd = LTTNG_POLL_GETFD(&events, i);
1006
1007 health_code_update(&consumer_data->health);
1008
1009 /* Thread quit pipe has been closed. Killing thread. */
1010 ret = check_thread_quit_pipe(pollfd, revents);
1011 if (ret) {
1012 err = 0;
1013 goto exit;
1014 }
1015
1016 /* Event on the kconsumerd socket */
1017 if (pollfd == sock) {
1018 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1019 ERR("consumer err socket second poll error");
1020 goto error;
1021 }
1022 }
1023 }
1024
1025 health_code_update(&consumer_data->health);
1026
1027 /* Wait for any kconsumerd error */
1028 ret = lttcomm_recv_unix_sock(sock, &code,
1029 sizeof(enum lttcomm_return_code));
1030 if (ret <= 0) {
1031 ERR("consumer closed the command socket");
1032 goto error;
1033 }
1034
1035 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1036
1037 exit:
1038 error:
1039 /* Immediately set the consumerd state to stopped */
1040 if (consumer_data->type == LTTNG_CONSUMER_KERNEL) {
1041 uatomic_set(&kernel_consumerd_state, CONSUMER_ERROR);
1042 } else if (consumer_data->type == LTTNG_CONSUMER64_UST ||
1043 consumer_data->type == LTTNG_CONSUMER32_UST) {
1044 uatomic_set(&ust_consumerd_state, CONSUMER_ERROR);
1045 } else {
1046 /* Code flow error... */
1047 assert(0);
1048 }
1049
1050 if (consumer_data->err_sock >= 0) {
1051 ret = close(consumer_data->err_sock);
1052 if (ret) {
1053 PERROR("close");
1054 }
1055 }
1056 if (consumer_data->cmd_sock >= 0) {
1057 ret = close(consumer_data->cmd_sock);
1058 if (ret) {
1059 PERROR("close");
1060 }
1061 }
1062 if (sock >= 0) {
1063 ret = close(sock);
1064 if (ret) {
1065 PERROR("close");
1066 }
1067 }
1068
1069 unlink(consumer_data->err_unix_sock_path);
1070 unlink(consumer_data->cmd_unix_sock_path);
1071 consumer_data->pid = 0;
1072
1073 lttng_poll_clean(&events);
1074 error_poll:
1075 if (err) {
1076 health_error(&consumer_data->health);
1077 ERR("Health error occurred in %s", __func__);
1078 }
1079 health_exit(&consumer_data->health);
1080 DBG("consumer thread cleanup completed");
1081
1082 return NULL;
1083 }
1084
1085 /*
1086 * This thread manage application communication.
1087 */
1088 static void *thread_manage_apps(void *data)
1089 {
1090 int i, ret, pollfd, err = -1;
1091 uint32_t revents, nb_fd;
1092 struct ust_command ust_cmd;
1093 struct lttng_poll_event events;
1094
1095 DBG("[thread] Manage application started");
1096
1097 testpoint(thread_manage_apps);
1098
1099 rcu_register_thread();
1100 rcu_thread_online();
1101
1102 health_code_update(&health_thread_app_manage);
1103
1104 ret = create_thread_poll_set(&events, 2);
1105 if (ret < 0) {
1106 goto error_poll_create;
1107 }
1108
1109 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1110 if (ret < 0) {
1111 goto error;
1112 }
1113
1114 testpoint(thread_manage_apps_before_loop);
1115
1116 health_code_update(&health_thread_app_manage);
1117
1118 while (1) {
1119 /* Zeroed the events structure */
1120 lttng_poll_reset(&events);
1121
1122 nb_fd = LTTNG_POLL_GETNB(&events);
1123
1124 DBG("Apps thread polling on %d fds", nb_fd);
1125
1126 /* Inifinite blocking call, waiting for transmission */
1127 restart:
1128 health_poll_update(&health_thread_app_manage);
1129 ret = lttng_poll_wait(&events, -1);
1130 health_poll_update(&health_thread_app_manage);
1131 if (ret < 0) {
1132 /*
1133 * Restart interrupted system call.
1134 */
1135 if (errno == EINTR) {
1136 goto restart;
1137 }
1138 goto error;
1139 }
1140
1141 for (i = 0; i < nb_fd; i++) {
1142 /* Fetch once the poll data */
1143 revents = LTTNG_POLL_GETEV(&events, i);
1144 pollfd = LTTNG_POLL_GETFD(&events, i);
1145
1146 health_code_update(&health_thread_app_manage);
1147
1148 /* Thread quit pipe has been closed. Killing thread. */
1149 ret = check_thread_quit_pipe(pollfd, revents);
1150 if (ret) {
1151 err = 0;
1152 goto exit;
1153 }
1154
1155 /* Inspect the apps cmd pipe */
1156 if (pollfd == apps_cmd_pipe[0]) {
1157 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1158 ERR("Apps command pipe error");
1159 goto error;
1160 } else if (revents & LPOLLIN) {
1161 /* Empty pipe */
1162 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1163 if (ret < 0 || ret < sizeof(ust_cmd)) {
1164 PERROR("read apps cmd pipe");
1165 goto error;
1166 }
1167
1168 health_code_update(&health_thread_app_manage);
1169
1170 /* Register applicaton to the session daemon */
1171 ret = ust_app_register(&ust_cmd.reg_msg,
1172 ust_cmd.sock);
1173 if (ret == -ENOMEM) {
1174 goto error;
1175 } else if (ret < 0) {
1176 break;
1177 }
1178
1179 health_code_update(&health_thread_app_manage);
1180
1181 /*
1182 * Validate UST version compatibility.
1183 */
1184 ret = ust_app_validate_version(ust_cmd.sock);
1185 if (ret >= 0) {
1186 /*
1187 * Add channel(s) and event(s) to newly registered apps
1188 * from lttng global UST domain.
1189 */
1190 update_ust_app(ust_cmd.sock);
1191 }
1192
1193 health_code_update(&health_thread_app_manage);
1194
1195 ret = ust_app_register_done(ust_cmd.sock);
1196 if (ret < 0) {
1197 /*
1198 * If the registration is not possible, we simply
1199 * unregister the apps and continue
1200 */
1201 ust_app_unregister(ust_cmd.sock);
1202 } else {
1203 /*
1204 * We only monitor the error events of the socket. This
1205 * thread does not handle any incoming data from UST
1206 * (POLLIN).
1207 */
1208 ret = lttng_poll_add(&events, ust_cmd.sock,
1209 LPOLLERR & LPOLLHUP & LPOLLRDHUP);
1210 if (ret < 0) {
1211 goto error;
1212 }
1213
1214 /* Set socket timeout for both receiving and ending */
1215 (void) lttcomm_setsockopt_rcv_timeout(ust_cmd.sock,
1216 app_socket_timeout);
1217 (void) lttcomm_setsockopt_snd_timeout(ust_cmd.sock,
1218 app_socket_timeout);
1219
1220 DBG("Apps with sock %d added to poll set",
1221 ust_cmd.sock);
1222 }
1223
1224 health_code_update(&health_thread_app_manage);
1225
1226 break;
1227 }
1228 } else {
1229 /*
1230 * At this point, we know that a registered application made
1231 * the event at poll_wait.
1232 */
1233 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1234 /* Removing from the poll set */
1235 ret = lttng_poll_del(&events, pollfd);
1236 if (ret < 0) {
1237 goto error;
1238 }
1239
1240 /* Socket closed on remote end. */
1241 ust_app_unregister(pollfd);
1242 break;
1243 }
1244 }
1245
1246 health_code_update(&health_thread_app_manage);
1247 }
1248 }
1249
1250 exit:
1251 error:
1252 lttng_poll_clean(&events);
1253 error_poll_create:
1254 utils_close_pipe(apps_cmd_pipe);
1255 apps_cmd_pipe[0] = apps_cmd_pipe[1] = -1;
1256
1257 /*
1258 * We don't clean the UST app hash table here since already registered
1259 * applications can still be controlled so let them be until the session
1260 * daemon dies or the applications stop.
1261 */
1262
1263 if (err) {
1264 health_error(&health_thread_app_manage);
1265 ERR("Health error occurred in %s", __func__);
1266 }
1267 health_exit(&health_thread_app_manage);
1268 DBG("Application communication apps thread cleanup complete");
1269 rcu_thread_offline();
1270 rcu_unregister_thread();
1271 return NULL;
1272 }
1273
1274 /*
1275 * Dispatch request from the registration threads to the application
1276 * communication thread.
1277 */
1278 static void *thread_dispatch_ust_registration(void *data)
1279 {
1280 int ret;
1281 struct cds_wfq_node *node;
1282 struct ust_command *ust_cmd = NULL;
1283
1284 DBG("[thread] Dispatch UST command started");
1285
1286 while (!CMM_LOAD_SHARED(dispatch_thread_exit)) {
1287 /* Atomically prepare the queue futex */
1288 futex_nto1_prepare(&ust_cmd_queue.futex);
1289
1290 do {
1291 /* Dequeue command for registration */
1292 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1293 if (node == NULL) {
1294 DBG("Woken up but nothing in the UST command queue");
1295 /* Continue thread execution */
1296 break;
1297 }
1298
1299 ust_cmd = caa_container_of(node, struct ust_command, node);
1300
1301 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1302 " gid:%d sock:%d name:%s (version %d.%d)",
1303 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1304 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1305 ust_cmd->sock, ust_cmd->reg_msg.name,
1306 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1307 /*
1308 * Inform apps thread of the new application registration. This
1309 * call is blocking so we can be assured that the data will be read
1310 * at some point in time or wait to the end of the world :)
1311 */
1312 if (apps_cmd_pipe[1] >= 0) {
1313 ret = write(apps_cmd_pipe[1], ust_cmd,
1314 sizeof(struct ust_command));
1315 if (ret < 0) {
1316 PERROR("write apps cmd pipe");
1317 if (errno == EBADF) {
1318 /*
1319 * We can't inform the application thread to process
1320 * registration. We will exit or else application
1321 * registration will not occur and tracing will never
1322 * start.
1323 */
1324 goto error;
1325 }
1326 }
1327 } else {
1328 /* Application manager thread is not available. */
1329 ret = close(ust_cmd->sock);
1330 if (ret < 0) {
1331 PERROR("close ust_cmd sock");
1332 }
1333 }
1334 free(ust_cmd);
1335 } while (node != NULL);
1336
1337 /* Futex wait on queue. Blocking call on futex() */
1338 futex_nto1_wait(&ust_cmd_queue.futex);
1339 }
1340
1341 error:
1342 DBG("Dispatch thread dying");
1343 return NULL;
1344 }
1345
1346 /*
1347 * This thread manage application registration.
1348 */
1349 static void *thread_registration_apps(void *data)
1350 {
1351 int sock = -1, i, ret, pollfd, err = -1;
1352 uint32_t revents, nb_fd;
1353 struct lttng_poll_event events;
1354 /*
1355 * Get allocated in this thread, enqueued to a global queue, dequeued and
1356 * freed in the manage apps thread.
1357 */
1358 struct ust_command *ust_cmd = NULL;
1359
1360 DBG("[thread] Manage application registration started");
1361
1362 testpoint(thread_registration_apps);
1363
1364 ret = lttcomm_listen_unix_sock(apps_sock);
1365 if (ret < 0) {
1366 goto error_listen;
1367 }
1368
1369 /*
1370 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1371 * more will be added to this poll set.
1372 */
1373 ret = create_thread_poll_set(&events, 2);
1374 if (ret < 0) {
1375 goto error_create_poll;
1376 }
1377
1378 /* Add the application registration socket */
1379 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1380 if (ret < 0) {
1381 goto error_poll_add;
1382 }
1383
1384 /* Notify all applications to register */
1385 ret = notify_ust_apps(1);
1386 if (ret < 0) {
1387 ERR("Failed to notify applications or create the wait shared memory.\n"
1388 "Execution continues but there might be problem for already\n"
1389 "running applications that wishes to register.");
1390 }
1391
1392 while (1) {
1393 DBG("Accepting application registration");
1394
1395 nb_fd = LTTNG_POLL_GETNB(&events);
1396
1397 /* Inifinite blocking call, waiting for transmission */
1398 restart:
1399 health_poll_update(&health_thread_app_reg);
1400 ret = lttng_poll_wait(&events, -1);
1401 health_poll_update(&health_thread_app_reg);
1402 if (ret < 0) {
1403 /*
1404 * Restart interrupted system call.
1405 */
1406 if (errno == EINTR) {
1407 goto restart;
1408 }
1409 goto error;
1410 }
1411
1412 for (i = 0; i < nb_fd; i++) {
1413 health_code_update(&health_thread_app_reg);
1414
1415 /* Fetch once the poll data */
1416 revents = LTTNG_POLL_GETEV(&events, i);
1417 pollfd = LTTNG_POLL_GETFD(&events, i);
1418
1419 /* Thread quit pipe has been closed. Killing thread. */
1420 ret = check_thread_quit_pipe(pollfd, revents);
1421 if (ret) {
1422 err = 0;
1423 goto exit;
1424 }
1425
1426 /* Event on the registration socket */
1427 if (pollfd == apps_sock) {
1428 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1429 ERR("Register apps socket poll error");
1430 goto error;
1431 } else if (revents & LPOLLIN) {
1432 sock = lttcomm_accept_unix_sock(apps_sock);
1433 if (sock < 0) {
1434 goto error;
1435 }
1436
1437 /*
1438 * Set the CLOEXEC flag. Return code is useless because
1439 * either way, the show must go on.
1440 */
1441 (void) utils_set_fd_cloexec(sock);
1442
1443 /* Create UST registration command for enqueuing */
1444 ust_cmd = zmalloc(sizeof(struct ust_command));
1445 if (ust_cmd == NULL) {
1446 PERROR("ust command zmalloc");
1447 goto error;
1448 }
1449
1450 /*
1451 * Using message-based transmissions to ensure we don't
1452 * have to deal with partially received messages.
1453 */
1454 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
1455 if (ret < 0) {
1456 ERR("Exhausted file descriptors allowed for applications.");
1457 free(ust_cmd);
1458 ret = close(sock);
1459 if (ret) {
1460 PERROR("close");
1461 }
1462 sock = -1;
1463 continue;
1464 }
1465 health_code_update(&health_thread_app_reg);
1466 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1467 sizeof(struct ust_register_msg));
1468 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1469 if (ret < 0) {
1470 PERROR("lttcomm_recv_unix_sock register apps");
1471 } else {
1472 ERR("Wrong size received on apps register");
1473 }
1474 free(ust_cmd);
1475 ret = close(sock);
1476 if (ret) {
1477 PERROR("close");
1478 }
1479 lttng_fd_put(LTTNG_FD_APPS, 1);
1480 sock = -1;
1481 continue;
1482 }
1483 health_code_update(&health_thread_app_reg);
1484
1485 ust_cmd->sock = sock;
1486 sock = -1;
1487
1488 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1489 " gid:%d sock:%d name:%s (version %d.%d)",
1490 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1491 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1492 ust_cmd->sock, ust_cmd->reg_msg.name,
1493 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1494
1495 /*
1496 * Lock free enqueue the registration request. The red pill
1497 * has been taken! This apps will be part of the *system*.
1498 */
1499 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1500
1501 /*
1502 * Wake the registration queue futex. Implicit memory
1503 * barrier with the exchange in cds_wfq_enqueue.
1504 */
1505 futex_nto1_wake(&ust_cmd_queue.futex);
1506 }
1507 }
1508 }
1509 }
1510
1511 exit:
1512 error:
1513 if (err) {
1514 health_error(&health_thread_app_reg);
1515 ERR("Health error occurred in %s", __func__);
1516 }
1517 health_exit(&health_thread_app_reg);
1518
1519 /* Notify that the registration thread is gone */
1520 notify_ust_apps(0);
1521
1522 if (apps_sock >= 0) {
1523 ret = close(apps_sock);
1524 if (ret) {
1525 PERROR("close");
1526 }
1527 }
1528 if (sock >= 0) {
1529 ret = close(sock);
1530 if (ret) {
1531 PERROR("close");
1532 }
1533 lttng_fd_put(LTTNG_FD_APPS, 1);
1534 }
1535 unlink(apps_unix_sock_path);
1536
1537 error_poll_add:
1538 lttng_poll_clean(&events);
1539 error_listen:
1540 error_create_poll:
1541 DBG("UST Registration thread cleanup complete");
1542
1543 return NULL;
1544 }
1545
1546 /*
1547 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1548 * exec or it will fails.
1549 */
1550 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1551 {
1552 int ret, clock_ret;
1553 struct timespec timeout;
1554
1555 /* Make sure we set the readiness flag to 0 because we are NOT ready */
1556 consumer_data->consumer_thread_is_ready = 0;
1557
1558 /* Setup pthread condition */
1559 ret = pthread_condattr_init(&consumer_data->condattr);
1560 if (ret != 0) {
1561 errno = ret;
1562 PERROR("pthread_condattr_init consumer data");
1563 goto error;
1564 }
1565
1566 /*
1567 * Set the monotonic clock in order to make sure we DO NOT jump in time
1568 * between the clock_gettime() call and the timedwait call. See bug #324
1569 * for a more details and how we noticed it.
1570 */
1571 ret = pthread_condattr_setclock(&consumer_data->condattr, CLOCK_MONOTONIC);
1572 if (ret != 0) {
1573 errno = ret;
1574 PERROR("pthread_condattr_setclock consumer data");
1575 goto error;
1576 }
1577
1578 ret = pthread_cond_init(&consumer_data->cond, &consumer_data->condattr);
1579 if (ret != 0) {
1580 errno = ret;
1581 PERROR("pthread_cond_init consumer data");
1582 goto error;
1583 }
1584
1585 ret = pthread_create(&consumer_data->thread, NULL, thread_manage_consumer,
1586 consumer_data);
1587 if (ret != 0) {
1588 PERROR("pthread_create consumer");
1589 ret = -1;
1590 goto error;
1591 }
1592
1593 /* We are about to wait on a pthread condition */
1594 pthread_mutex_lock(&consumer_data->cond_mutex);
1595
1596 /* Get time for sem_timedwait absolute timeout */
1597 clock_ret = clock_gettime(CLOCK_MONOTONIC, &timeout);
1598 /*
1599 * Set the timeout for the condition timed wait even if the clock gettime
1600 * call fails since we might loop on that call and we want to avoid to
1601 * increment the timeout too many times.
1602 */
1603 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1604
1605 /*
1606 * The following loop COULD be skipped in some conditions so this is why we
1607 * set ret to 0 in order to make sure at least one round of the loop is
1608 * done.
1609 */
1610 ret = 0;
1611
1612 /*
1613 * Loop until the condition is reached or when a timeout is reached. Note
1614 * that the pthread_cond_timedwait(P) man page specifies that EINTR can NOT
1615 * be returned but the pthread_cond(3), from the glibc-doc, says that it is
1616 * possible. This loop does not take any chances and works with both of
1617 * them.
1618 */
1619 while (!consumer_data->consumer_thread_is_ready && ret != ETIMEDOUT) {
1620 if (clock_ret < 0) {
1621 PERROR("clock_gettime spawn consumer");
1622 /* Infinite wait for the consumerd thread to be ready */
1623 ret = pthread_cond_wait(&consumer_data->cond,
1624 &consumer_data->cond_mutex);
1625 } else {
1626 ret = pthread_cond_timedwait(&consumer_data->cond,
1627 &consumer_data->cond_mutex, &timeout);
1628 }
1629 }
1630
1631 /* Release the pthread condition */
1632 pthread_mutex_unlock(&consumer_data->cond_mutex);
1633
1634 if (ret != 0) {
1635 errno = ret;
1636 if (ret == ETIMEDOUT) {
1637 /*
1638 * Call has timed out so we kill the kconsumerd_thread and return
1639 * an error.
1640 */
1641 ERR("Condition timed out. The consumer thread was never ready."
1642 " Killing it");
1643 ret = pthread_cancel(consumer_data->thread);
1644 if (ret < 0) {
1645 PERROR("pthread_cancel consumer thread");
1646 }
1647 } else {
1648 PERROR("pthread_cond_wait failed consumer thread");
1649 }
1650 goto error;
1651 }
1652
1653 pthread_mutex_lock(&consumer_data->pid_mutex);
1654 if (consumer_data->pid == 0) {
1655 ERR("Consumerd did not start");
1656 pthread_mutex_unlock(&consumer_data->pid_mutex);
1657 goto error;
1658 }
1659 pthread_mutex_unlock(&consumer_data->pid_mutex);
1660
1661 return 0;
1662
1663 error:
1664 return ret;
1665 }
1666
1667 /*
1668 * Join consumer thread
1669 */
1670 static int join_consumer_thread(struct consumer_data *consumer_data)
1671 {
1672 void *status;
1673 int ret;
1674
1675 /* Consumer pid must be a real one. */
1676 if (consumer_data->pid > 0) {
1677 ret = kill(consumer_data->pid, SIGTERM);
1678 if (ret) {
1679 ERR("Error killing consumer daemon");
1680 return ret;
1681 }
1682 return pthread_join(consumer_data->thread, &status);
1683 } else {
1684 return 0;
1685 }
1686 }
1687
1688 /*
1689 * Fork and exec a consumer daemon (consumerd).
1690 *
1691 * Return pid if successful else -1.
1692 */
1693 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1694 {
1695 int ret;
1696 pid_t pid;
1697 const char *consumer_to_use;
1698 const char *verbosity;
1699 struct stat st;
1700
1701 DBG("Spawning consumerd");
1702
1703 pid = fork();
1704 if (pid == 0) {
1705 /*
1706 * Exec consumerd.
1707 */
1708 if (opt_verbose_consumer) {
1709 verbosity = "--verbose";
1710 } else {
1711 verbosity = "--quiet";
1712 }
1713 switch (consumer_data->type) {
1714 case LTTNG_CONSUMER_KERNEL:
1715 /*
1716 * Find out which consumerd to execute. We will first try the
1717 * 64-bit path, then the sessiond's installation directory, and
1718 * fallback on the 32-bit one,
1719 */
1720 DBG3("Looking for a kernel consumer at these locations:");
1721 DBG3(" 1) %s", consumerd64_bin);
1722 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1723 DBG3(" 3) %s", consumerd32_bin);
1724 if (stat(consumerd64_bin, &st) == 0) {
1725 DBG3("Found location #1");
1726 consumer_to_use = consumerd64_bin;
1727 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1728 DBG3("Found location #2");
1729 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1730 } else if (stat(consumerd32_bin, &st) == 0) {
1731 DBG3("Found location #3");
1732 consumer_to_use = consumerd32_bin;
1733 } else {
1734 DBG("Could not find any valid consumerd executable");
1735 break;
1736 }
1737 DBG("Using kernel consumer at: %s", consumer_to_use);
1738 execl(consumer_to_use,
1739 "lttng-consumerd", verbosity, "-k",
1740 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1741 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1742 NULL);
1743 break;
1744 case LTTNG_CONSUMER64_UST:
1745 {
1746 char *tmpnew = NULL;
1747
1748 if (consumerd64_libdir[0] != '\0') {
1749 char *tmp;
1750 size_t tmplen;
1751
1752 tmp = getenv("LD_LIBRARY_PATH");
1753 if (!tmp) {
1754 tmp = "";
1755 }
1756 tmplen = strlen("LD_LIBRARY_PATH=")
1757 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1758 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1759 if (!tmpnew) {
1760 ret = -ENOMEM;
1761 goto error;
1762 }
1763 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1764 strcat(tmpnew, consumerd64_libdir);
1765 if (tmp[0] != '\0') {
1766 strcat(tmpnew, ":");
1767 strcat(tmpnew, tmp);
1768 }
1769 ret = putenv(tmpnew);
1770 if (ret) {
1771 ret = -errno;
1772 goto error;
1773 }
1774 }
1775 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1776 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1777 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1778 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1779 NULL);
1780 if (consumerd64_libdir[0] != '\0') {
1781 free(tmpnew);
1782 }
1783 if (ret) {
1784 goto error;
1785 }
1786 break;
1787 }
1788 case LTTNG_CONSUMER32_UST:
1789 {
1790 char *tmpnew = NULL;
1791
1792 if (consumerd32_libdir[0] != '\0') {
1793 char *tmp;
1794 size_t tmplen;
1795
1796 tmp = getenv("LD_LIBRARY_PATH");
1797 if (!tmp) {
1798 tmp = "";
1799 }
1800 tmplen = strlen("LD_LIBRARY_PATH=")
1801 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1802 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1803 if (!tmpnew) {
1804 ret = -ENOMEM;
1805 goto error;
1806 }
1807 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1808 strcat(tmpnew, consumerd32_libdir);
1809 if (tmp[0] != '\0') {
1810 strcat(tmpnew, ":");
1811 strcat(tmpnew, tmp);
1812 }
1813 ret = putenv(tmpnew);
1814 if (ret) {
1815 ret = -errno;
1816 goto error;
1817 }
1818 }
1819 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1820 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1821 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1822 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1823 NULL);
1824 if (consumerd32_libdir[0] != '\0') {
1825 free(tmpnew);
1826 }
1827 if (ret) {
1828 goto error;
1829 }
1830 break;
1831 }
1832 default:
1833 PERROR("unknown consumer type");
1834 exit(EXIT_FAILURE);
1835 }
1836 if (errno != 0) {
1837 PERROR("kernel start consumer exec");
1838 }
1839 exit(EXIT_FAILURE);
1840 } else if (pid > 0) {
1841 ret = pid;
1842 } else {
1843 PERROR("start consumer fork");
1844 ret = -errno;
1845 }
1846 error:
1847 return ret;
1848 }
1849
1850 /*
1851 * Spawn the consumerd daemon and session daemon thread.
1852 */
1853 static int start_consumerd(struct consumer_data *consumer_data)
1854 {
1855 int ret, err;
1856
1857 /*
1858 * Set the listen() state on the socket since there is a possible race
1859 * between the exec() of the consumer daemon and this call if place in the
1860 * consumer thread. See bug #366 for more details.
1861 */
1862 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
1863 if (ret < 0) {
1864 goto error;
1865 }
1866
1867 pthread_mutex_lock(&consumer_data->pid_mutex);
1868 if (consumer_data->pid != 0) {
1869 pthread_mutex_unlock(&consumer_data->pid_mutex);
1870 goto end;
1871 }
1872
1873 ret = spawn_consumerd(consumer_data);
1874 if (ret < 0) {
1875 ERR("Spawning consumerd failed");
1876 pthread_mutex_unlock(&consumer_data->pid_mutex);
1877 goto error;
1878 }
1879
1880 /* Setting up the consumer_data pid */
1881 consumer_data->pid = ret;
1882 DBG2("Consumer pid %d", consumer_data->pid);
1883 pthread_mutex_unlock(&consumer_data->pid_mutex);
1884
1885 DBG2("Spawning consumer control thread");
1886 ret = spawn_consumer_thread(consumer_data);
1887 if (ret < 0) {
1888 ERR("Fatal error spawning consumer control thread");
1889 goto error;
1890 }
1891
1892 end:
1893 return 0;
1894
1895 error:
1896 /* Cleanup already created socket on error. */
1897 if (consumer_data->err_sock >= 0) {
1898 err = close(consumer_data->err_sock);
1899 if (err < 0) {
1900 PERROR("close consumer data error socket");
1901 }
1902 }
1903 return ret;
1904 }
1905
1906 /*
1907 * Compute health status of each consumer. If one of them is zero (bad
1908 * state), we return 0.
1909 */
1910 static int check_consumer_health(void)
1911 {
1912 int ret;
1913
1914 ret = health_check_state(&kconsumer_data.health) &&
1915 health_check_state(&ustconsumer32_data.health) &&
1916 health_check_state(&ustconsumer64_data.health);
1917
1918 DBG3("Health consumer check %d", ret);
1919
1920 return ret;
1921 }
1922
1923 /*
1924 * Setup necessary data for kernel tracer action.
1925 */
1926 static int init_kernel_tracer(void)
1927 {
1928 int ret;
1929
1930 /* Modprobe lttng kernel modules */
1931 ret = modprobe_lttng_control();
1932 if (ret < 0) {
1933 goto error;
1934 }
1935
1936 /* Open debugfs lttng */
1937 kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
1938 if (kernel_tracer_fd < 0) {
1939 DBG("Failed to open %s", module_proc_lttng);
1940 ret = -1;
1941 goto error_open;
1942 }
1943
1944 /* Validate kernel version */
1945 ret = kernel_validate_version(kernel_tracer_fd);
1946 if (ret < 0) {
1947 goto error_version;
1948 }
1949
1950 ret = modprobe_lttng_data();
1951 if (ret < 0) {
1952 goto error_modules;
1953 }
1954
1955 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1956 return 0;
1957
1958 error_version:
1959 modprobe_remove_lttng_control();
1960 ret = close(kernel_tracer_fd);
1961 if (ret) {
1962 PERROR("close");
1963 }
1964 kernel_tracer_fd = -1;
1965 return LTTNG_ERR_KERN_VERSION;
1966
1967 error_modules:
1968 ret = close(kernel_tracer_fd);
1969 if (ret) {
1970 PERROR("close");
1971 }
1972
1973 error_open:
1974 modprobe_remove_lttng_control();
1975
1976 error:
1977 WARN("No kernel tracer available");
1978 kernel_tracer_fd = -1;
1979 if (!is_root) {
1980 return LTTNG_ERR_NEED_ROOT_SESSIOND;
1981 } else {
1982 return LTTNG_ERR_KERN_NA;
1983 }
1984 }
1985
1986
1987 /*
1988 * Copy consumer output from the tracing session to the domain session. The
1989 * function also applies the right modification on a per domain basis for the
1990 * trace files destination directory.
1991 */
1992 static int copy_session_consumer(int domain, struct ltt_session *session)
1993 {
1994 int ret;
1995 const char *dir_name;
1996 struct consumer_output *consumer;
1997
1998 assert(session);
1999 assert(session->consumer);
2000
2001 switch (domain) {
2002 case LTTNG_DOMAIN_KERNEL:
2003 DBG3("Copying tracing session consumer output in kernel session");
2004 /*
2005 * XXX: We should audit the session creation and what this function
2006 * does "extra" in order to avoid a destroy since this function is used
2007 * in the domain session creation (kernel and ust) only. Same for UST
2008 * domain.
2009 */
2010 if (session->kernel_session->consumer) {
2011 consumer_destroy_output(session->kernel_session->consumer);
2012 }
2013 session->kernel_session->consumer =
2014 consumer_copy_output(session->consumer);
2015 /* Ease our life a bit for the next part */
2016 consumer = session->kernel_session->consumer;
2017 dir_name = DEFAULT_KERNEL_TRACE_DIR;
2018 break;
2019 case LTTNG_DOMAIN_UST:
2020 DBG3("Copying tracing session consumer output in UST session");
2021 if (session->ust_session->consumer) {
2022 consumer_destroy_output(session->ust_session->consumer);
2023 }
2024 session->ust_session->consumer =
2025 consumer_copy_output(session->consumer);
2026 /* Ease our life a bit for the next part */
2027 consumer = session->ust_session->consumer;
2028 dir_name = DEFAULT_UST_TRACE_DIR;
2029 break;
2030 default:
2031 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
2032 goto error;
2033 }
2034
2035 /* Append correct directory to subdir */
2036 strncat(consumer->subdir, dir_name,
2037 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
2038 DBG3("Copy session consumer subdir %s", consumer->subdir);
2039
2040 ret = LTTNG_OK;
2041
2042 error:
2043 return ret;
2044 }
2045
2046 /*
2047 * Create an UST session and add it to the session ust list.
2048 */
2049 static int create_ust_session(struct ltt_session *session,
2050 struct lttng_domain *domain)
2051 {
2052 int ret;
2053 struct ltt_ust_session *lus = NULL;
2054
2055 assert(session);
2056 assert(domain);
2057 assert(session->consumer);
2058
2059 switch (domain->type) {
2060 case LTTNG_DOMAIN_UST:
2061 break;
2062 default:
2063 ERR("Unknown UST domain on create session %d", domain->type);
2064 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
2065 goto error;
2066 }
2067
2068 DBG("Creating UST session");
2069
2070 lus = trace_ust_create_session(session->path, session->id, domain);
2071 if (lus == NULL) {
2072 ret = LTTNG_ERR_UST_SESS_FAIL;
2073 goto error;
2074 }
2075
2076 lus->uid = session->uid;
2077 lus->gid = session->gid;
2078 session->ust_session = lus;
2079
2080 /* Copy session output to the newly created UST session */
2081 ret = copy_session_consumer(domain->type, session);
2082 if (ret != LTTNG_OK) {
2083 goto error;
2084 }
2085
2086 return LTTNG_OK;
2087
2088 error:
2089 free(lus);
2090 session->ust_session = NULL;
2091 return ret;
2092 }
2093
2094 /*
2095 * Create a kernel tracer session then create the default channel.
2096 */
2097 static int create_kernel_session(struct ltt_session *session)
2098 {
2099 int ret;
2100
2101 DBG("Creating kernel session");
2102
2103 ret = kernel_create_session(session, kernel_tracer_fd);
2104 if (ret < 0) {
2105 ret = LTTNG_ERR_KERN_SESS_FAIL;
2106 goto error;
2107 }
2108
2109 /* Code flow safety */
2110 assert(session->kernel_session);
2111
2112 /* Copy session output to the newly created Kernel session */
2113 ret = copy_session_consumer(LTTNG_DOMAIN_KERNEL, session);
2114 if (ret != LTTNG_OK) {
2115 goto error;
2116 }
2117
2118 /* Create directory(ies) on local filesystem. */
2119 if (session->kernel_session->consumer->type == CONSUMER_DST_LOCAL &&
2120 strlen(session->kernel_session->consumer->dst.trace_path) > 0) {
2121 ret = run_as_mkdir_recursive(
2122 session->kernel_session->consumer->dst.trace_path,
2123 S_IRWXU | S_IRWXG, session->uid, session->gid);
2124 if (ret < 0) {
2125 if (ret != -EEXIST) {
2126 ERR("Trace directory creation error");
2127 goto error;
2128 }
2129 }
2130 }
2131
2132 session->kernel_session->uid = session->uid;
2133 session->kernel_session->gid = session->gid;
2134
2135 return LTTNG_OK;
2136
2137 error:
2138 trace_kernel_destroy_session(session->kernel_session);
2139 session->kernel_session = NULL;
2140 return ret;
2141 }
2142
2143 /*
2144 * Count number of session permitted by uid/gid.
2145 */
2146 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
2147 {
2148 unsigned int i = 0;
2149 struct ltt_session *session;
2150
2151 DBG("Counting number of available session for UID %d GID %d",
2152 uid, gid);
2153 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2154 /*
2155 * Only list the sessions the user can control.
2156 */
2157 if (!session_access_ok(session, uid, gid)) {
2158 continue;
2159 }
2160 i++;
2161 }
2162 return i;
2163 }
2164
2165 /*
2166 * Process the command requested by the lttng client within the command
2167 * context structure. This function make sure that the return structure (llm)
2168 * is set and ready for transmission before returning.
2169 *
2170 * Return any error encountered or 0 for success.
2171 *
2172 * "sock" is only used for special-case var. len data.
2173 */
2174 static int process_client_msg(struct command_ctx *cmd_ctx, int sock,
2175 int *sock_error)
2176 {
2177 int ret = LTTNG_OK;
2178 int need_tracing_session = 1;
2179 int need_domain;
2180
2181 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
2182
2183 *sock_error = 0;
2184
2185 switch (cmd_ctx->lsm->cmd_type) {
2186 case LTTNG_CREATE_SESSION:
2187 case LTTNG_DESTROY_SESSION:
2188 case LTTNG_LIST_SESSIONS:
2189 case LTTNG_LIST_DOMAINS:
2190 case LTTNG_START_TRACE:
2191 case LTTNG_STOP_TRACE:
2192 case LTTNG_DATA_PENDING:
2193 need_domain = 0;
2194 break;
2195 default:
2196 need_domain = 1;
2197 }
2198
2199 if (opt_no_kernel && need_domain
2200 && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
2201 if (!is_root) {
2202 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
2203 } else {
2204 ret = LTTNG_ERR_KERN_NA;
2205 }
2206 goto error;
2207 }
2208
2209 /* Deny register consumer if we already have a spawned consumer. */
2210 if (cmd_ctx->lsm->cmd_type == LTTNG_REGISTER_CONSUMER) {
2211 pthread_mutex_lock(&kconsumer_data.pid_mutex);
2212 if (kconsumer_data.pid > 0) {
2213 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2214 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2215 goto error;
2216 }
2217 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2218 }
2219
2220 /*
2221 * Check for command that don't needs to allocate a returned payload. We do
2222 * this here so we don't have to make the call for no payload at each
2223 * command.
2224 */
2225 switch(cmd_ctx->lsm->cmd_type) {
2226 case LTTNG_LIST_SESSIONS:
2227 case LTTNG_LIST_TRACEPOINTS:
2228 case LTTNG_LIST_TRACEPOINT_FIELDS:
2229 case LTTNG_LIST_DOMAINS:
2230 case LTTNG_LIST_CHANNELS:
2231 case LTTNG_LIST_EVENTS:
2232 break;
2233 default:
2234 /* Setup lttng message with no payload */
2235 ret = setup_lttng_msg(cmd_ctx, 0);
2236 if (ret < 0) {
2237 /* This label does not try to unlock the session */
2238 goto init_setup_error;
2239 }
2240 }
2241
2242 /* Commands that DO NOT need a session. */
2243 switch (cmd_ctx->lsm->cmd_type) {
2244 case LTTNG_CREATE_SESSION:
2245 case LTTNG_CALIBRATE:
2246 case LTTNG_LIST_SESSIONS:
2247 case LTTNG_LIST_TRACEPOINTS:
2248 case LTTNG_LIST_TRACEPOINT_FIELDS:
2249 need_tracing_session = 0;
2250 break;
2251 default:
2252 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
2253 /*
2254 * We keep the session list lock across _all_ commands
2255 * for now, because the per-session lock does not
2256 * handle teardown properly.
2257 */
2258 session_lock_list();
2259 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
2260 if (cmd_ctx->session == NULL) {
2261 if (cmd_ctx->lsm->session.name != NULL) {
2262 ret = LTTNG_ERR_SESS_NOT_FOUND;
2263 } else {
2264 /* If no session name specified */
2265 ret = LTTNG_ERR_SELECT_SESS;
2266 }
2267 goto error;
2268 } else {
2269 /* Acquire lock for the session */
2270 session_lock(cmd_ctx->session);
2271 }
2272 break;
2273 }
2274
2275 if (!need_domain) {
2276 goto skip_domain;
2277 }
2278
2279 /*
2280 * Check domain type for specific "pre-action".
2281 */
2282 switch (cmd_ctx->lsm->domain.type) {
2283 case LTTNG_DOMAIN_KERNEL:
2284 if (!is_root) {
2285 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
2286 goto error;
2287 }
2288
2289 /* Kernel tracer check */
2290 if (kernel_tracer_fd == -1) {
2291 /* Basically, load kernel tracer modules */
2292 ret = init_kernel_tracer();
2293 if (ret != 0) {
2294 goto error;
2295 }
2296 }
2297
2298 /* Consumer is in an ERROR state. Report back to client */
2299 if (uatomic_read(&kernel_consumerd_state) == CONSUMER_ERROR) {
2300 ret = LTTNG_ERR_NO_KERNCONSUMERD;
2301 goto error;
2302 }
2303
2304 /* Need a session for kernel command */
2305 if (need_tracing_session) {
2306 if (cmd_ctx->session->kernel_session == NULL) {
2307 ret = create_kernel_session(cmd_ctx->session);
2308 if (ret < 0) {
2309 ret = LTTNG_ERR_KERN_SESS_FAIL;
2310 goto error;
2311 }
2312 }
2313
2314 /* Start the kernel consumer daemon */
2315 pthread_mutex_lock(&kconsumer_data.pid_mutex);
2316 if (kconsumer_data.pid == 0 &&
2317 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER &&
2318 cmd_ctx->session->start_consumer) {
2319 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2320 ret = start_consumerd(&kconsumer_data);
2321 if (ret < 0) {
2322 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2323 goto error;
2324 }
2325 uatomic_set(&kernel_consumerd_state, CONSUMER_STARTED);
2326 } else {
2327 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2328 }
2329
2330 /*
2331 * The consumer was just spawned so we need to add the socket to
2332 * the consumer output of the session if exist.
2333 */
2334 ret = consumer_create_socket(&kconsumer_data,
2335 cmd_ctx->session->kernel_session->consumer);
2336 if (ret < 0) {
2337 goto error;
2338 }
2339 }
2340
2341 break;
2342 case LTTNG_DOMAIN_UST:
2343 {
2344 /* Consumer is in an ERROR state. Report back to client */
2345 if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
2346 ret = LTTNG_ERR_NO_USTCONSUMERD;
2347 goto error;
2348 }
2349
2350 if (need_tracing_session) {
2351 /* Create UST session if none exist. */
2352 if (cmd_ctx->session->ust_session == NULL) {
2353 ret = create_ust_session(cmd_ctx->session,
2354 &cmd_ctx->lsm->domain);
2355 if (ret != LTTNG_OK) {
2356 goto error;
2357 }
2358 }
2359
2360 /* Start the UST consumer daemons */
2361 /* 64-bit */
2362 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
2363 if (consumerd64_bin[0] != '\0' &&
2364 ustconsumer64_data.pid == 0 &&
2365 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER &&
2366 cmd_ctx->session->start_consumer) {
2367 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
2368 ret = start_consumerd(&ustconsumer64_data);
2369 if (ret < 0) {
2370 ret = LTTNG_ERR_UST_CONSUMER64_FAIL;
2371 uatomic_set(&ust_consumerd64_fd, -EINVAL);
2372 goto error;
2373 }
2374
2375 uatomic_set(&ust_consumerd64_fd, ustconsumer64_data.cmd_sock);
2376 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
2377 } else {
2378 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
2379 }
2380
2381 /*
2382 * Setup socket for consumer 64 bit. No need for atomic access
2383 * since it was set above and can ONLY be set in this thread.
2384 */
2385 ret = consumer_create_socket(&ustconsumer64_data,
2386 cmd_ctx->session->ust_session->consumer);
2387 if (ret < 0) {
2388 goto error;
2389 }
2390
2391 /* 32-bit */
2392 if (consumerd32_bin[0] != '\0' &&
2393 ustconsumer32_data.pid == 0 &&
2394 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER &&
2395 cmd_ctx->session->start_consumer) {
2396 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
2397 ret = start_consumerd(&ustconsumer32_data);
2398 if (ret < 0) {
2399 ret = LTTNG_ERR_UST_CONSUMER32_FAIL;
2400 uatomic_set(&ust_consumerd32_fd, -EINVAL);
2401 goto error;
2402 }
2403
2404 uatomic_set(&ust_consumerd32_fd, ustconsumer32_data.cmd_sock);
2405 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
2406 } else {
2407 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
2408 }
2409
2410 /*
2411 * Setup socket for consumer 64 bit. No need for atomic access
2412 * since it was set above and can ONLY be set in this thread.
2413 */
2414 ret = consumer_create_socket(&ustconsumer32_data,
2415 cmd_ctx->session->ust_session->consumer);
2416 if (ret < 0) {
2417 goto error;
2418 }
2419 }
2420 break;
2421 }
2422 default:
2423 break;
2424 }
2425 skip_domain:
2426
2427 /* Validate consumer daemon state when start/stop trace command */
2428 if (cmd_ctx->lsm->cmd_type == LTTNG_START_TRACE ||
2429 cmd_ctx->lsm->cmd_type == LTTNG_STOP_TRACE) {
2430 switch (cmd_ctx->lsm->domain.type) {
2431 case LTTNG_DOMAIN_UST:
2432 if (uatomic_read(&ust_consumerd_state) != CONSUMER_STARTED) {
2433 ret = LTTNG_ERR_NO_USTCONSUMERD;
2434 goto error;
2435 }
2436 break;
2437 case LTTNG_DOMAIN_KERNEL:
2438 if (uatomic_read(&kernel_consumerd_state) != CONSUMER_STARTED) {
2439 ret = LTTNG_ERR_NO_KERNCONSUMERD;
2440 goto error;
2441 }
2442 break;
2443 }
2444 }
2445
2446 /*
2447 * Check that the UID or GID match that of the tracing session.
2448 * The root user can interact with all sessions.
2449 */
2450 if (need_tracing_session) {
2451 if (!session_access_ok(cmd_ctx->session,
2452 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
2453 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds))) {
2454 ret = LTTNG_ERR_EPERM;
2455 goto error;
2456 }
2457 }
2458
2459 /* Process by command type */
2460 switch (cmd_ctx->lsm->cmd_type) {
2461 case LTTNG_ADD_CONTEXT:
2462 {
2463 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2464 cmd_ctx->lsm->u.context.channel_name,
2465 &cmd_ctx->lsm->u.context.ctx, kernel_poll_pipe[1]);
2466 break;
2467 }
2468 case LTTNG_DISABLE_CHANNEL:
2469 {
2470 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2471 cmd_ctx->lsm->u.disable.channel_name);
2472 break;
2473 }
2474 case LTTNG_DISABLE_EVENT:
2475 {
2476 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2477 cmd_ctx->lsm->u.disable.channel_name,
2478 cmd_ctx->lsm->u.disable.name);
2479 break;
2480 }
2481 case LTTNG_DISABLE_ALL_EVENT:
2482 {
2483 DBG("Disabling all events");
2484
2485 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2486 cmd_ctx->lsm->u.disable.channel_name);
2487 break;
2488 }
2489 case LTTNG_DISABLE_CONSUMER:
2490 {
2491 ret = cmd_disable_consumer(cmd_ctx->lsm->domain.type, cmd_ctx->session);
2492 break;
2493 }
2494 case LTTNG_ENABLE_CHANNEL:
2495 {
2496 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2497 &cmd_ctx->lsm->u.channel.chan, kernel_poll_pipe[1]);
2498 break;
2499 }
2500 case LTTNG_ENABLE_CONSUMER:
2501 {
2502 /*
2503 * XXX: 0 means that this URI should be applied on the session. Should
2504 * be a DOMAIN enuam.
2505 */
2506 ret = cmd_enable_consumer(cmd_ctx->lsm->domain.type, cmd_ctx->session);
2507 if (ret != LTTNG_OK) {
2508 goto error;
2509 }
2510
2511 if (cmd_ctx->lsm->domain.type == 0) {
2512 /* Add the URI for the UST session if a consumer is present. */
2513 if (cmd_ctx->session->ust_session &&
2514 cmd_ctx->session->ust_session->consumer) {
2515 ret = cmd_enable_consumer(LTTNG_DOMAIN_UST, cmd_ctx->session);
2516 } else if (cmd_ctx->session->kernel_session &&
2517 cmd_ctx->session->kernel_session->consumer) {
2518 ret = cmd_enable_consumer(LTTNG_DOMAIN_KERNEL,
2519 cmd_ctx->session);
2520 }
2521 }
2522 break;
2523 }
2524 case LTTNG_ENABLE_EVENT:
2525 {
2526 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2527 cmd_ctx->lsm->u.enable.channel_name,
2528 &cmd_ctx->lsm->u.enable.event, kernel_poll_pipe[1]);
2529 break;
2530 }
2531 case LTTNG_ENABLE_ALL_EVENT:
2532 {
2533 DBG("Enabling all events");
2534
2535 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2536 cmd_ctx->lsm->u.enable.channel_name,
2537 cmd_ctx->lsm->u.enable.event.type, kernel_poll_pipe[1]);
2538 break;
2539 }
2540 case LTTNG_LIST_TRACEPOINTS:
2541 {
2542 struct lttng_event *events;
2543 ssize_t nb_events;
2544
2545 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
2546 if (nb_events < 0) {
2547 /* Return value is a negative lttng_error_code. */
2548 ret = -nb_events;
2549 goto error;
2550 }
2551
2552 /*
2553 * Setup lttng message with payload size set to the event list size in
2554 * bytes and then copy list into the llm payload.
2555 */
2556 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
2557 if (ret < 0) {
2558 free(events);
2559 goto setup_error;
2560 }
2561
2562 /* Copy event list into message payload */
2563 memcpy(cmd_ctx->llm->payload, events,
2564 sizeof(struct lttng_event) * nb_events);
2565
2566 free(events);
2567
2568 ret = LTTNG_OK;
2569 break;
2570 }
2571 case LTTNG_LIST_TRACEPOINT_FIELDS:
2572 {
2573 struct lttng_event_field *fields;
2574 ssize_t nb_fields;
2575
2576 nb_fields = cmd_list_tracepoint_fields(cmd_ctx->lsm->domain.type,
2577 &fields);
2578 if (nb_fields < 0) {
2579 /* Return value is a negative lttng_error_code. */
2580 ret = -nb_fields;
2581 goto error;
2582 }
2583
2584 /*
2585 * Setup lttng message with payload size set to the event list size in
2586 * bytes and then copy list into the llm payload.
2587 */
2588 ret = setup_lttng_msg(cmd_ctx,
2589 sizeof(struct lttng_event_field) * nb_fields);
2590 if (ret < 0) {
2591 free(fields);
2592 goto setup_error;
2593 }
2594
2595 /* Copy event list into message payload */
2596 memcpy(cmd_ctx->llm->payload, fields,
2597 sizeof(struct lttng_event_field) * nb_fields);
2598
2599 free(fields);
2600
2601 ret = LTTNG_OK;
2602 break;
2603 }
2604 case LTTNG_SET_CONSUMER_URI:
2605 {
2606 size_t nb_uri, len;
2607 struct lttng_uri *uris;
2608
2609 nb_uri = cmd_ctx->lsm->u.uri.size;
2610 len = nb_uri * sizeof(struct lttng_uri);
2611
2612 if (nb_uri == 0) {
2613 ret = LTTNG_ERR_INVALID;
2614 goto error;
2615 }
2616
2617 uris = zmalloc(len);
2618 if (uris == NULL) {
2619 ret = LTTNG_ERR_FATAL;
2620 goto error;
2621 }
2622
2623 /* Receive variable len data */
2624 DBG("Receiving %zu URI(s) from client ...", nb_uri);
2625 ret = lttcomm_recv_unix_sock(sock, uris, len);
2626 if (ret <= 0) {
2627 DBG("No URIs received from client... continuing");
2628 *sock_error = 1;
2629 ret = LTTNG_ERR_SESSION_FAIL;
2630 free(uris);
2631 goto error;
2632 }
2633
2634 ret = cmd_set_consumer_uri(cmd_ctx->lsm->domain.type, cmd_ctx->session,
2635 nb_uri, uris);
2636 if (ret != LTTNG_OK) {
2637 free(uris);
2638 goto error;
2639 }
2640
2641 /*
2642 * XXX: 0 means that this URI should be applied on the session. Should
2643 * be a DOMAIN enuam.
2644 */
2645 if (cmd_ctx->lsm->domain.type == 0) {
2646 /* Add the URI for the UST session if a consumer is present. */
2647 if (cmd_ctx->session->ust_session &&
2648 cmd_ctx->session->ust_session->consumer) {
2649 ret = cmd_set_consumer_uri(LTTNG_DOMAIN_UST, cmd_ctx->session,
2650 nb_uri, uris);
2651 } else if (cmd_ctx->session->kernel_session &&
2652 cmd_ctx->session->kernel_session->consumer) {
2653 ret = cmd_set_consumer_uri(LTTNG_DOMAIN_KERNEL,
2654 cmd_ctx->session, nb_uri, uris);
2655 }
2656 }
2657
2658 free(uris);
2659
2660 break;
2661 }
2662 case LTTNG_START_TRACE:
2663 {
2664 ret = cmd_start_trace(cmd_ctx->session);
2665 break;
2666 }
2667 case LTTNG_STOP_TRACE:
2668 {
2669 ret = cmd_stop_trace(cmd_ctx->session);
2670 break;
2671 }
2672 case LTTNG_CREATE_SESSION:
2673 {
2674 size_t nb_uri, len;
2675 struct lttng_uri *uris = NULL;
2676
2677 nb_uri = cmd_ctx->lsm->u.uri.size;
2678 len = nb_uri * sizeof(struct lttng_uri);
2679
2680 if (nb_uri > 0) {
2681 uris = zmalloc(len);
2682 if (uris == NULL) {
2683 ret = LTTNG_ERR_FATAL;
2684 goto error;
2685 }
2686
2687 /* Receive variable len data */
2688 DBG("Waiting for %zu URIs from client ...", nb_uri);
2689 ret = lttcomm_recv_unix_sock(sock, uris, len);
2690 if (ret <= 0) {
2691 DBG("No URIs received from client... continuing");
2692 *sock_error = 1;
2693 ret = LTTNG_ERR_SESSION_FAIL;
2694 free(uris);
2695 goto error;
2696 }
2697
2698 if (nb_uri == 1 && uris[0].dtype != LTTNG_DST_PATH) {
2699 DBG("Creating session with ONE network URI is a bad call");
2700 ret = LTTNG_ERR_SESSION_FAIL;
2701 free(uris);
2702 goto error;
2703 }
2704 }
2705
2706 ret = cmd_create_session_uri(cmd_ctx->lsm->session.name, uris, nb_uri,
2707 &cmd_ctx->creds);
2708
2709 free(uris);
2710
2711 break;
2712 }
2713 case LTTNG_DESTROY_SESSION:
2714 {
2715 ret = cmd_destroy_session(cmd_ctx->session, kernel_poll_pipe[1]);
2716
2717 /* Set session to NULL so we do not unlock it after free. */
2718 cmd_ctx->session = NULL;
2719 break;
2720 }
2721 case LTTNG_LIST_DOMAINS:
2722 {
2723 ssize_t nb_dom;
2724 struct lttng_domain *domains;
2725
2726 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
2727 if (nb_dom < 0) {
2728 /* Return value is a negative lttng_error_code. */
2729 ret = -nb_dom;
2730 goto error;
2731 }
2732
2733 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
2734 if (ret < 0) {
2735 goto setup_error;
2736 }
2737
2738 /* Copy event list into message payload */
2739 memcpy(cmd_ctx->llm->payload, domains,
2740 nb_dom * sizeof(struct lttng_domain));
2741
2742 free(domains);
2743
2744 ret = LTTNG_OK;
2745 break;
2746 }
2747 case LTTNG_LIST_CHANNELS:
2748 {
2749 int nb_chan;
2750 struct lttng_channel *channels;
2751
2752 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
2753 cmd_ctx->session, &channels);
2754 if (nb_chan < 0) {
2755 /* Return value is a negative lttng_error_code. */
2756 ret = -nb_chan;
2757 goto error;
2758 }
2759
2760 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
2761 if (ret < 0) {
2762 goto setup_error;
2763 }
2764
2765 /* Copy event list into message payload */
2766 memcpy(cmd_ctx->llm->payload, channels,
2767 nb_chan * sizeof(struct lttng_channel));
2768
2769 free(channels);
2770
2771 ret = LTTNG_OK;
2772 break;
2773 }
2774 case LTTNG_LIST_EVENTS:
2775 {
2776 ssize_t nb_event;
2777 struct lttng_event *events = NULL;
2778
2779 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
2780 cmd_ctx->lsm->u.list.channel_name, &events);
2781 if (nb_event < 0) {
2782 /* Return value is a negative lttng_error_code. */
2783 ret = -nb_event;
2784 goto error;
2785 }
2786
2787 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
2788 if (ret < 0) {
2789 goto setup_error;
2790 }
2791
2792 /* Copy event list into message payload */
2793 memcpy(cmd_ctx->llm->payload, events,
2794 nb_event * sizeof(struct lttng_event));
2795
2796 free(events);
2797
2798 ret = LTTNG_OK;
2799 break;
2800 }
2801 case LTTNG_LIST_SESSIONS:
2802 {
2803 unsigned int nr_sessions;
2804
2805 session_lock_list();
2806 nr_sessions = lttng_sessions_count(
2807 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
2808 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
2809
2810 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * nr_sessions);
2811 if (ret < 0) {
2812 session_unlock_list();
2813 goto setup_error;
2814 }
2815
2816 /* Filled the session array */
2817 cmd_list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload),
2818 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
2819 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
2820
2821 session_unlock_list();
2822
2823 ret = LTTNG_OK;
2824 break;
2825 }
2826 case LTTNG_CALIBRATE:
2827 {
2828 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
2829 &cmd_ctx->lsm->u.calibrate);
2830 break;
2831 }
2832 case LTTNG_REGISTER_CONSUMER:
2833 {
2834 struct consumer_data *cdata;
2835
2836 switch (cmd_ctx->lsm->domain.type) {
2837 case LTTNG_DOMAIN_KERNEL:
2838 cdata = &kconsumer_data;
2839 break;
2840 default:
2841 ret = LTTNG_ERR_UND;
2842 goto error;
2843 }
2844
2845 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2846 cmd_ctx->lsm->u.reg.path, cdata);
2847 break;
2848 }
2849 case LTTNG_SET_FILTER:
2850 {
2851 struct lttng_filter_bytecode *bytecode;
2852
2853 if (cmd_ctx->lsm->u.filter.bytecode_len > LTTNG_FILTER_MAX_LEN) {
2854 ret = LTTNG_ERR_FILTER_INVAL;
2855 goto error;
2856 }
2857 bytecode = zmalloc(cmd_ctx->lsm->u.filter.bytecode_len);
2858 if (!bytecode) {
2859 ret = LTTNG_ERR_FILTER_NOMEM;
2860 goto error;
2861 }
2862 /* Receive var. len. data */
2863 DBG("Receiving var len data from client ...");
2864 ret = lttcomm_recv_unix_sock(sock, bytecode,
2865 cmd_ctx->lsm->u.filter.bytecode_len);
2866 if (ret <= 0) {
2867 DBG("Nothing recv() from client var len data... continuing");
2868 *sock_error = 1;
2869 ret = LTTNG_ERR_FILTER_INVAL;
2870 goto error;
2871 }
2872
2873 if (bytecode->len + sizeof(*bytecode)
2874 != cmd_ctx->lsm->u.filter.bytecode_len) {
2875 free(bytecode);
2876 ret = LTTNG_ERR_FILTER_INVAL;
2877 goto error;
2878 }
2879
2880 ret = cmd_set_filter(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2881 cmd_ctx->lsm->u.filter.channel_name,
2882 cmd_ctx->lsm->u.filter.event_name,
2883 bytecode);
2884 break;
2885 }
2886 case LTTNG_DATA_PENDING:
2887 {
2888 ret = cmd_data_pending(cmd_ctx->session);
2889 break;
2890 }
2891 default:
2892 ret = LTTNG_ERR_UND;
2893 break;
2894 }
2895
2896 error:
2897 if (cmd_ctx->llm == NULL) {
2898 DBG("Missing llm structure. Allocating one.");
2899 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
2900 goto setup_error;
2901 }
2902 }
2903 /* Set return code */
2904 cmd_ctx->llm->ret_code = ret;
2905 setup_error:
2906 if (cmd_ctx->session) {
2907 session_unlock(cmd_ctx->session);
2908 }
2909 if (need_tracing_session) {
2910 session_unlock_list();
2911 }
2912 init_setup_error:
2913 return ret;
2914 }
2915
2916 /*
2917 * Thread managing health check socket.
2918 */
2919 static void *thread_manage_health(void *data)
2920 {
2921 int sock = -1, new_sock = -1, ret, i, pollfd, err = -1;
2922 uint32_t revents, nb_fd;
2923 struct lttng_poll_event events;
2924 struct lttcomm_health_msg msg;
2925 struct lttcomm_health_data reply;
2926
2927 DBG("[thread] Manage health check started");
2928
2929 rcu_register_thread();
2930
2931 /* Create unix socket */
2932 sock = lttcomm_create_unix_sock(health_unix_sock_path);
2933 if (sock < 0) {
2934 ERR("Unable to create health check Unix socket");
2935 ret = -1;
2936 goto error;
2937 }
2938
2939 /*
2940 * Set the CLOEXEC flag. Return code is useless because either way, the
2941 * show must go on.
2942 */
2943 (void) utils_set_fd_cloexec(sock);
2944
2945 ret = lttcomm_listen_unix_sock(sock);
2946 if (ret < 0) {
2947 goto error;
2948 }
2949
2950 /*
2951 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2952 * more will be added to this poll set.
2953 */
2954 ret = create_thread_poll_set(&events, 2);
2955 if (ret < 0) {
2956 goto error;
2957 }
2958
2959 /* Add the application registration socket */
2960 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLPRI);
2961 if (ret < 0) {
2962 goto error;
2963 }
2964
2965 while (1) {
2966 DBG("Health check ready");
2967
2968 nb_fd = LTTNG_POLL_GETNB(&events);
2969
2970 /* Inifinite blocking call, waiting for transmission */
2971 restart:
2972 ret = lttng_poll_wait(&events, -1);
2973 if (ret < 0) {
2974 /*
2975 * Restart interrupted system call.
2976 */
2977 if (errno == EINTR) {
2978 goto restart;
2979 }
2980 goto error;
2981 }
2982
2983 for (i = 0; i < nb_fd; i++) {
2984 /* Fetch once the poll data */
2985 revents = LTTNG_POLL_GETEV(&events, i);
2986 pollfd = LTTNG_POLL_GETFD(&events, i);
2987
2988 /* Thread quit pipe has been closed. Killing thread. */
2989 ret = check_thread_quit_pipe(pollfd, revents);
2990 if (ret) {
2991 err = 0;
2992 goto exit;
2993 }
2994
2995 /* Event on the registration socket */
2996 if (pollfd == sock) {
2997 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2998 ERR("Health socket poll error");
2999 goto error;
3000 }
3001 }
3002 }
3003
3004 new_sock = lttcomm_accept_unix_sock(sock);
3005 if (new_sock < 0) {
3006 goto error;
3007 }
3008
3009 /*
3010 * Set the CLOEXEC flag. Return code is useless because either way, the
3011 * show must go on.
3012 */
3013 (void) utils_set_fd_cloexec(new_sock);
3014
3015 DBG("Receiving data from client for health...");
3016 ret = lttcomm_recv_unix_sock(new_sock, (void *)&msg, sizeof(msg));
3017 if (ret <= 0) {
3018 DBG("Nothing recv() from client... continuing");
3019 ret = close(new_sock);
3020 if (ret) {
3021 PERROR("close");
3022 }
3023 new_sock = -1;
3024 continue;
3025 }
3026
3027 rcu_thread_online();
3028
3029 switch (msg.component) {
3030 case LTTNG_HEALTH_CMD:
3031 reply.ret_code = health_check_state(&health_thread_cmd);
3032 break;
3033 case LTTNG_HEALTH_APP_MANAGE:
3034 reply.ret_code = health_check_state(&health_thread_app_manage);
3035 break;
3036 case LTTNG_HEALTH_APP_REG:
3037 reply.ret_code = health_check_state(&health_thread_app_reg);
3038 break;
3039 case LTTNG_HEALTH_KERNEL:
3040 reply.ret_code = health_check_state(&health_thread_kernel);
3041 break;
3042 case LTTNG_HEALTH_CONSUMER:
3043 reply.ret_code = check_consumer_health();
3044 break;
3045 case LTTNG_HEALTH_ALL:
3046 reply.ret_code =
3047 health_check_state(&health_thread_app_manage) &&
3048 health_check_state(&health_thread_app_reg) &&
3049 health_check_state(&health_thread_cmd) &&
3050 health_check_state(&health_thread_kernel) &&
3051 check_consumer_health();
3052 break;
3053 default:
3054 reply.ret_code = LTTNG_ERR_UND;
3055 break;
3056 }
3057
3058 /*
3059 * Flip ret value since 0 is a success and 1 indicates a bad health for
3060 * the client where in the sessiond it is the opposite. Again, this is
3061 * just to make things easier for us poor developer which enjoy a lot
3062 * lazyness.
3063 */
3064 if (reply.ret_code == 0 || reply.ret_code == 1) {
3065 reply.ret_code = !reply.ret_code;
3066 }
3067
3068 DBG2("Health check return value %d", reply.ret_code);
3069
3070 ret = send_unix_sock(new_sock, (void *) &reply, sizeof(reply));
3071 if (ret < 0) {
3072 ERR("Failed to send health data back to client");
3073 }
3074
3075 /* End of transmission */
3076 ret = close(new_sock);
3077 if (ret) {
3078 PERROR("close");
3079 }
3080 new_sock = -1;
3081 }
3082
3083 exit:
3084 error:
3085 if (err) {
3086 ERR("Health error occurred in %s", __func__);
3087 }
3088 DBG("Health check thread dying");
3089 unlink(health_unix_sock_path);
3090 if (sock >= 0) {
3091 ret = close(sock);
3092 if (ret) {
3093 PERROR("close");
3094 }
3095 }
3096 if (new_sock >= 0) {
3097 ret = close(new_sock);
3098 if (ret) {
3099 PERROR("close");
3100 }
3101 }
3102
3103 lttng_poll_clean(&events);
3104
3105 rcu_unregister_thread();
3106 return NULL;
3107 }
3108
3109 /*
3110 * This thread manage all clients request using the unix client socket for
3111 * communication.
3112 */
3113 static void *thread_manage_clients(void *data)
3114 {
3115 int sock = -1, ret, i, pollfd, err = -1;
3116 int sock_error;
3117 uint32_t revents, nb_fd;
3118 struct command_ctx *cmd_ctx = NULL;
3119 struct lttng_poll_event events;
3120
3121 DBG("[thread] Manage client started");
3122
3123 testpoint(thread_manage_clients);
3124
3125 rcu_register_thread();
3126
3127 health_code_update(&health_thread_cmd);
3128
3129 ret = lttcomm_listen_unix_sock(client_sock);
3130 if (ret < 0) {
3131 goto error_listen;
3132 }
3133
3134 /*
3135 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3136 * more will be added to this poll set.
3137 */
3138 ret = create_thread_poll_set(&events, 2);
3139 if (ret < 0) {
3140 goto error_create_poll;
3141 }
3142
3143 /* Add the application registration socket */
3144 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3145 if (ret < 0) {
3146 goto error;
3147 }
3148
3149 /*
3150 * Notify parent pid that we are ready to accept command for client side.
3151 */
3152 if (opt_sig_parent) {
3153 kill(ppid, SIGUSR1);
3154 }
3155
3156 testpoint(thread_manage_clients_before_loop);
3157
3158 health_code_update(&health_thread_cmd);
3159
3160 while (1) {
3161 DBG("Accepting client command ...");
3162
3163 nb_fd = LTTNG_POLL_GETNB(&events);
3164
3165 /* Inifinite blocking call, waiting for transmission */
3166 restart:
3167 health_poll_update(&health_thread_cmd);
3168 ret = lttng_poll_wait(&events, -1);
3169 health_poll_update(&health_thread_cmd);
3170 if (ret < 0) {
3171 /*
3172 * Restart interrupted system call.
3173 */
3174 if (errno == EINTR) {
3175 goto restart;
3176 }
3177 goto error;
3178 }
3179
3180 for (i = 0; i < nb_fd; i++) {
3181 /* Fetch once the poll data */
3182 revents = LTTNG_POLL_GETEV(&events, i);
3183 pollfd = LTTNG_POLL_GETFD(&events, i);
3184
3185 health_code_update(&health_thread_cmd);
3186
3187 /* Thread quit pipe has been closed. Killing thread. */
3188 ret = check_thread_quit_pipe(pollfd, revents);
3189 if (ret) {
3190 err = 0;
3191 goto exit;
3192 }
3193
3194 /* Event on the registration socket */
3195 if (pollfd == client_sock) {
3196 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3197 ERR("Client socket poll error");
3198 goto error;
3199 }
3200 }
3201 }
3202
3203 DBG("Wait for client response");
3204
3205 health_code_update(&health_thread_cmd);
3206
3207 sock = lttcomm_accept_unix_sock(client_sock);
3208 if (sock < 0) {
3209 goto error;
3210 }
3211
3212 /*
3213 * Set the CLOEXEC flag. Return code is useless because either way, the
3214 * show must go on.
3215 */
3216 (void) utils_set_fd_cloexec(sock);
3217
3218 /* Set socket option for credentials retrieval */
3219 ret = lttcomm_setsockopt_creds_unix_sock(sock);
3220 if (ret < 0) {
3221 goto error;
3222 }
3223
3224 /* Allocate context command to process the client request */
3225 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3226 if (cmd_ctx == NULL) {
3227 PERROR("zmalloc cmd_ctx");
3228 goto error;
3229 }
3230
3231 /* Allocate data buffer for reception */
3232 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3233 if (cmd_ctx->lsm == NULL) {
3234 PERROR("zmalloc cmd_ctx->lsm");
3235 goto error;
3236 }
3237
3238 cmd_ctx->llm = NULL;
3239 cmd_ctx->session = NULL;
3240
3241 health_code_update(&health_thread_cmd);
3242
3243 /*
3244 * Data is received from the lttng client. The struct
3245 * lttcomm_session_msg (lsm) contains the command and data request of
3246 * the client.
3247 */
3248 DBG("Receiving data from client ...");
3249 ret = lttcomm_recv_creds_unix_sock(sock, cmd_ctx->lsm,
3250 sizeof(struct lttcomm_session_msg), &cmd_ctx->creds);
3251 if (ret <= 0) {
3252 DBG("Nothing recv() from client... continuing");
3253 ret = close(sock);
3254 if (ret) {
3255 PERROR("close");
3256 }
3257 sock = -1;
3258 clean_command_ctx(&cmd_ctx);
3259 continue;
3260 }
3261
3262 health_code_update(&health_thread_cmd);
3263
3264 // TODO: Validate cmd_ctx including sanity check for
3265 // security purpose.
3266
3267 rcu_thread_online();
3268 /*
3269 * This function dispatch the work to the kernel or userspace tracer
3270 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3271 * informations for the client. The command context struct contains
3272 * everything this function may needs.
3273 */
3274 ret = process_client_msg(cmd_ctx, sock, &sock_error);
3275 rcu_thread_offline();
3276 if (ret < 0) {
3277 if (sock_error) {
3278 ret = close(sock);
3279 if (ret) {
3280 PERROR("close");
3281 }
3282 sock = -1;
3283 }
3284 /*
3285 * TODO: Inform client somehow of the fatal error. At
3286 * this point, ret < 0 means that a zmalloc failed
3287 * (ENOMEM). Error detected but still accept
3288 * command, unless a socket error has been
3289 * detected.
3290 */
3291 clean_command_ctx(&cmd_ctx);
3292 continue;
3293 }
3294
3295 health_code_update(&health_thread_cmd);
3296
3297 DBG("Sending response (size: %d, retcode: %s)",
3298 cmd_ctx->lttng_msg_size,
3299 lttng_strerror(-cmd_ctx->llm->ret_code));
3300 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3301 if (ret < 0) {
3302 ERR("Failed to send data back to client");
3303 }
3304
3305 /* End of transmission */
3306 ret = close(sock);
3307 if (ret) {
3308 PERROR("close");
3309 }
3310 sock = -1;
3311
3312 clean_command_ctx(&cmd_ctx);
3313
3314 health_code_update(&health_thread_cmd);
3315 }
3316
3317 exit:
3318 error:
3319 if (sock >= 0) {
3320 ret = close(sock);
3321 if (ret) {
3322 PERROR("close");
3323 }
3324 }
3325
3326 lttng_poll_clean(&events);
3327 clean_command_ctx(&cmd_ctx);
3328
3329 error_listen:
3330 error_create_poll:
3331 unlink(client_unix_sock_path);
3332 if (client_sock >= 0) {
3333 ret = close(client_sock);
3334 if (ret) {
3335 PERROR("close");
3336 }
3337 }
3338
3339 if (err) {
3340 health_error(&health_thread_cmd);
3341 ERR("Health error occurred in %s", __func__);
3342 }
3343
3344 health_exit(&health_thread_cmd);
3345
3346 DBG("Client thread dying");
3347
3348 rcu_unregister_thread();
3349 return NULL;
3350 }
3351
3352
3353 /*
3354 * usage function on stderr
3355 */
3356 static void usage(void)
3357 {
3358 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3359 fprintf(stderr, " -h, --help Display this usage.\n");
3360 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3361 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3362 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3363 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3364 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
3365 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
3366 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
3367 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
3368 fprintf(stderr, " --consumerd32-path PATH Specify path for the 32-bit UST consumer daemon binary\n");
3369 fprintf(stderr, " --consumerd32-libdir PATH Specify path for the 32-bit UST consumer daemon libraries\n");
3370 fprintf(stderr, " --consumerd64-path PATH Specify path for the 64-bit UST consumer daemon binary\n");
3371 fprintf(stderr, " --consumerd64-libdir PATH Specify path for the 64-bit UST consumer daemon libraries\n");
3372 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3373 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3374 fprintf(stderr, " -V, --version Show version number.\n");
3375 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3376 fprintf(stderr, " -q, --quiet No output at all.\n");
3377 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3378 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3379 fprintf(stderr, " --no-kernel Disable kernel tracer\n");
3380 }
3381
3382 /*
3383 * daemon argument parsing
3384 */
3385 static int parse_args(int argc, char **argv)
3386 {
3387 int c;
3388
3389 static struct option long_options[] = {
3390 { "client-sock", 1, 0, 'c' },
3391 { "apps-sock", 1, 0, 'a' },
3392 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3393 { "kconsumerd-err-sock", 1, 0, 'E' },
3394 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
3395 { "ustconsumerd32-err-sock", 1, 0, 'H' },
3396 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
3397 { "ustconsumerd64-err-sock", 1, 0, 'F' },
3398 { "consumerd32-path", 1, 0, 'u' },
3399 { "consumerd32-libdir", 1, 0, 'U' },
3400 { "consumerd64-path", 1, 0, 't' },
3401 { "consumerd64-libdir", 1, 0, 'T' },
3402 { "daemonize", 0, 0, 'd' },
3403 { "sig-parent", 0, 0, 'S' },
3404 { "help", 0, 0, 'h' },
3405 { "group", 1, 0, 'g' },
3406 { "version", 0, 0, 'V' },
3407 { "quiet", 0, 0, 'q' },
3408 { "verbose", 0, 0, 'v' },
3409 { "verbose-consumer", 0, 0, 'Z' },
3410 { "no-kernel", 0, 0, 'N' },
3411 { NULL, 0, 0, 0 }
3412 };
3413
3414 while (1) {
3415 int option_index = 0;
3416 c = getopt_long(argc, argv, "dhqvVSN" "a:c:g:s:C:E:D:F:Z:u:t",
3417 long_options, &option_index);
3418 if (c == -1) {
3419 break;
3420 }
3421
3422 switch (c) {
3423 case 0:
3424 fprintf(stderr, "option %s", long_options[option_index].name);
3425 if (optarg) {
3426 fprintf(stderr, " with arg %s\n", optarg);
3427 }
3428 break;
3429 case 'c':
3430 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3431 break;
3432 case 'a':
3433 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3434 break;
3435 case 'd':
3436 opt_daemon = 1;
3437 break;
3438 case 'g':
3439 opt_tracing_group = optarg;
3440 break;
3441 case 'h':
3442 usage();
3443 exit(EXIT_FAILURE);
3444 case 'V':
3445 fprintf(stdout, "%s\n", VERSION);
3446 exit(EXIT_SUCCESS);
3447 case 'S':
3448 opt_sig_parent = 1;
3449 break;
3450 case 'E':
3451 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3452 break;
3453 case 'C':
3454 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3455 break;
3456 case 'F':
3457 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3458 break;
3459 case 'D':
3460 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3461 break;
3462 case 'H':
3463 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3464 break;
3465 case 'G':
3466 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3467 break;
3468 case 'N':
3469 opt_no_kernel = 1;
3470 break;
3471 case 'q':
3472 lttng_opt_quiet = 1;
3473 break;
3474 case 'v':
3475 /* Verbose level can increase using multiple -v */
3476 lttng_opt_verbose += 1;
3477 break;
3478 case 'Z':
3479 opt_verbose_consumer += 1;
3480 break;
3481 case 'u':
3482 consumerd32_bin= optarg;
3483 break;
3484 case 'U':
3485 consumerd32_libdir = optarg;
3486 break;
3487 case 't':
3488 consumerd64_bin = optarg;
3489 break;
3490 case 'T':
3491 consumerd64_libdir = optarg;
3492 break;
3493 default:
3494 /* Unknown option or other error.
3495 * Error is printed by getopt, just return */
3496 return -1;
3497 }
3498 }
3499
3500 return 0;
3501 }
3502
3503 /*
3504 * Creates the two needed socket by the daemon.
3505 * apps_sock - The communication socket for all UST apps.
3506 * client_sock - The communication of the cli tool (lttng).
3507 */
3508 static int init_daemon_socket(void)
3509 {
3510 int ret = 0;
3511 mode_t old_umask;
3512
3513 old_umask = umask(0);
3514
3515 /* Create client tool unix socket */
3516 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3517 if (client_sock < 0) {
3518 ERR("Create unix sock failed: %s", client_unix_sock_path);
3519 ret = -1;
3520 goto end;
3521 }
3522
3523 /* Set the cloexec flag */
3524 ret = utils_set_fd_cloexec(client_sock);
3525 if (ret < 0) {
3526 ERR("Unable to set CLOEXEC flag to the client Unix socket (fd: %d). "
3527 "Continuing but note that the consumer daemon will have a "
3528 "reference to this socket on exec()", client_sock);
3529 }
3530
3531 /* File permission MUST be 660 */
3532 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3533 if (ret < 0) {
3534 ERR("Set file permissions failed: %s", client_unix_sock_path);
3535 PERROR("chmod");
3536 goto end;
3537 }
3538
3539 /* Create the application unix socket */
3540 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3541 if (apps_sock < 0) {
3542 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3543 ret = -1;
3544 goto end;
3545 }
3546
3547 /* Set the cloexec flag */
3548 ret = utils_set_fd_cloexec(apps_sock);
3549 if (ret < 0) {
3550 ERR("Unable to set CLOEXEC flag to the app Unix socket (fd: %d). "
3551 "Continuing but note that the consumer daemon will have a "
3552 "reference to this socket on exec()", apps_sock);
3553 }
3554
3555 /* File permission MUST be 666 */
3556 ret = chmod(apps_unix_sock_path,
3557 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3558 if (ret < 0) {
3559 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3560 PERROR("chmod");
3561 goto end;
3562 }
3563
3564 DBG3("Session daemon client socket %d and application socket %d created",
3565 client_sock, apps_sock);
3566
3567 end:
3568 umask(old_umask);
3569 return ret;
3570 }
3571
3572 /*
3573 * Check if the global socket is available, and if a daemon is answering at the
3574 * other side. If yes, error is returned.
3575 */
3576 static int check_existing_daemon(void)
3577 {
3578 /* Is there anybody out there ? */
3579 if (lttng_session_daemon_alive()) {
3580 return -EEXIST;
3581 }
3582
3583 return 0;
3584 }
3585
3586 /*
3587 * Set the tracing group gid onto the client socket.
3588 *
3589 * Race window between mkdir and chown is OK because we are going from more
3590 * permissive (root.root) to less permissive (root.tracing).
3591 */
3592 static int set_permissions(char *rundir)
3593 {
3594 int ret;
3595 gid_t gid;
3596
3597 ret = allowed_group();
3598 if (ret < 0) {
3599 WARN("No tracing group detected");
3600 ret = 0;
3601 goto end;
3602 }
3603
3604 gid = ret;
3605
3606 /* Set lttng run dir */
3607 ret = chown(rundir, 0, gid);
3608 if (ret < 0) {
3609 ERR("Unable to set group on %s", rundir);
3610 PERROR("chown");
3611 }
3612
3613 /* Ensure tracing group can search the run dir */
3614 ret = chmod(rundir, S_IRWXU | S_IXGRP | S_IXOTH);
3615 if (ret < 0) {
3616 ERR("Unable to set permissions on %s", rundir);
3617 PERROR("chmod");
3618 }
3619
3620 /* lttng client socket path */
3621 ret = chown(client_unix_sock_path, 0, gid);
3622 if (ret < 0) {
3623 ERR("Unable to set group on %s", client_unix_sock_path);
3624 PERROR("chown");
3625 }
3626
3627 /* kconsumer error socket path */
3628 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
3629 if (ret < 0) {
3630 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
3631 PERROR("chown");
3632 }
3633
3634 /* 64-bit ustconsumer error socket path */
3635 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
3636 if (ret < 0) {
3637 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
3638 PERROR("chown");
3639 }
3640
3641 /* 32-bit ustconsumer compat32 error socket path */
3642 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
3643 if (ret < 0) {
3644 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
3645 PERROR("chown");
3646 }
3647
3648 DBG("All permissions are set");
3649
3650 end:
3651 return ret;
3652 }
3653
3654 /*
3655 * Create the lttng run directory needed for all global sockets and pipe.
3656 */
3657 static int create_lttng_rundir(const char *rundir)
3658 {
3659 int ret;
3660
3661 DBG3("Creating LTTng run directory: %s", rundir);
3662
3663 ret = mkdir(rundir, S_IRWXU);
3664 if (ret < 0) {
3665 if (errno != EEXIST) {
3666 ERR("Unable to create %s", rundir);
3667 goto error;
3668 } else {
3669 ret = 0;
3670 }
3671 }
3672
3673 error:
3674 return ret;
3675 }
3676
3677 /*
3678 * Setup sockets and directory needed by the kconsumerd communication with the
3679 * session daemon.
3680 */
3681 static int set_consumer_sockets(struct consumer_data *consumer_data,
3682 const char *rundir)
3683 {
3684 int ret;
3685 char path[PATH_MAX];
3686
3687 switch (consumer_data->type) {
3688 case LTTNG_CONSUMER_KERNEL:
3689 snprintf(path, PATH_MAX, DEFAULT_KCONSUMERD_PATH, rundir);
3690 break;
3691 case LTTNG_CONSUMER64_UST:
3692 snprintf(path, PATH_MAX, DEFAULT_USTCONSUMERD64_PATH, rundir);
3693 break;
3694 case LTTNG_CONSUMER32_UST:
3695 snprintf(path, PATH_MAX, DEFAULT_USTCONSUMERD32_PATH, rundir);
3696 break;
3697 default:
3698 ERR("Consumer type unknown");
3699 ret = -EINVAL;
3700 goto error;
3701 }
3702
3703 DBG2("Creating consumer directory: %s", path);
3704
3705 ret = mkdir(path, S_IRWXU);
3706 if (ret < 0) {
3707 if (errno != EEXIST) {
3708 PERROR("mkdir");
3709 ERR("Failed to create %s", path);
3710 goto error;
3711 }
3712 ret = -1;
3713 }
3714
3715 /* Create the kconsumerd error unix socket */
3716 consumer_data->err_sock =
3717 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
3718 if (consumer_data->err_sock < 0) {
3719 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
3720 ret = -1;
3721 goto error;
3722 }
3723
3724 /* File permission MUST be 660 */
3725 ret = chmod(consumer_data->err_unix_sock_path,
3726 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3727 if (ret < 0) {
3728 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
3729 PERROR("chmod");
3730 goto error;
3731 }
3732
3733 error:
3734 return ret;
3735 }
3736
3737 /*
3738 * Signal handler for the daemon
3739 *
3740 * Simply stop all worker threads, leaving main() return gracefully after
3741 * joining all threads and calling cleanup().
3742 */
3743 static void sighandler(int sig)
3744 {
3745 switch (sig) {
3746 case SIGPIPE:
3747 DBG("SIGPIPE caught");
3748 return;
3749 case SIGINT:
3750 DBG("SIGINT caught");
3751 stop_threads();
3752 break;
3753 case SIGTERM:
3754 DBG("SIGTERM caught");
3755 stop_threads();
3756 break;
3757 default:
3758 break;
3759 }
3760 }
3761
3762 /*
3763 * Setup signal handler for :
3764 * SIGINT, SIGTERM, SIGPIPE
3765 */
3766 static int set_signal_handler(void)
3767 {
3768 int ret = 0;
3769 struct sigaction sa;
3770 sigset_t sigset;
3771
3772 if ((ret = sigemptyset(&sigset)) < 0) {
3773 PERROR("sigemptyset");
3774 return ret;
3775 }
3776
3777 sa.sa_handler = sighandler;
3778 sa.sa_mask = sigset;
3779 sa.sa_flags = 0;
3780 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
3781 PERROR("sigaction");
3782 return ret;
3783 }
3784
3785 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
3786 PERROR("sigaction");
3787 return ret;
3788 }
3789
3790 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
3791 PERROR("sigaction");
3792 return ret;
3793 }
3794
3795 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3796
3797 return ret;
3798 }
3799
3800 /*
3801 * Set open files limit to unlimited. This daemon can open a large number of
3802 * file descriptors in order to consumer multiple kernel traces.
3803 */
3804 static void set_ulimit(void)
3805 {
3806 int ret;
3807 struct rlimit lim;
3808
3809 /* The kernel does not allowed an infinite limit for open files */
3810 lim.rlim_cur = 65535;
3811 lim.rlim_max = 65535;
3812
3813 ret = setrlimit(RLIMIT_NOFILE, &lim);
3814 if (ret < 0) {
3815 PERROR("failed to set open files limit");
3816 }
3817 }
3818
3819 /*
3820 * main
3821 */
3822 int main(int argc, char **argv)
3823 {
3824 int ret = 0;
3825 void *status;
3826 const char *home_path, *env_app_timeout;
3827
3828 init_kernel_workarounds();
3829
3830 rcu_register_thread();
3831
3832 setup_consumerd_path();
3833
3834 /* Parse arguments */
3835 progname = argv[0];
3836 if ((ret = parse_args(argc, argv) < 0)) {
3837 goto error;
3838 }
3839
3840 /* Daemonize */
3841 if (opt_daemon) {
3842 int i;
3843
3844 /*
3845 * fork
3846 * child: setsid, close FD 0, 1, 2, chdir /
3847 * parent: exit (if fork is successful)
3848 */
3849 ret = daemon(0, 0);
3850 if (ret < 0) {
3851 PERROR("daemon");
3852 goto error;
3853 }
3854 /*
3855 * We are in the child. Make sure all other file
3856 * descriptors are closed, in case we are called with
3857 * more opened file descriptors than the standard ones.
3858 */
3859 for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
3860 (void) close(i);
3861 }
3862 }
3863
3864 /* Create thread quit pipe */
3865 if ((ret = init_thread_quit_pipe()) < 0) {
3866 goto error;
3867 }
3868
3869 /* Check if daemon is UID = 0 */
3870 is_root = !getuid();
3871
3872 if (is_root) {
3873 rundir = strdup(DEFAULT_LTTNG_RUNDIR);
3874
3875 /* Create global run dir with root access */
3876 ret = create_lttng_rundir(rundir);
3877 if (ret < 0) {
3878 goto error;
3879 }
3880
3881 if (strlen(apps_unix_sock_path) == 0) {
3882 snprintf(apps_unix_sock_path, PATH_MAX,
3883 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
3884 }
3885
3886 if (strlen(client_unix_sock_path) == 0) {
3887 snprintf(client_unix_sock_path, PATH_MAX,
3888 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
3889 }
3890
3891 /* Set global SHM for ust */
3892 if (strlen(wait_shm_path) == 0) {
3893 snprintf(wait_shm_path, PATH_MAX,
3894 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
3895 }
3896
3897 if (strlen(health_unix_sock_path) == 0) {
3898 snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
3899 DEFAULT_GLOBAL_HEALTH_UNIX_SOCK);
3900 }
3901
3902 /* Setup kernel consumerd path */
3903 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX,
3904 DEFAULT_KCONSUMERD_ERR_SOCK_PATH, rundir);
3905 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX,
3906 DEFAULT_KCONSUMERD_CMD_SOCK_PATH, rundir);
3907
3908 DBG2("Kernel consumer err path: %s",
3909 kconsumer_data.err_unix_sock_path);
3910 DBG2("Kernel consumer cmd path: %s",
3911 kconsumer_data.cmd_unix_sock_path);
3912 } else {
3913 home_path = get_home_dir();
3914 if (home_path == NULL) {
3915 /* TODO: Add --socket PATH option */
3916 ERR("Can't get HOME directory for sockets creation.");
3917 ret = -EPERM;
3918 goto error;
3919 }
3920
3921 /*
3922 * Create rundir from home path. This will create something like
3923 * $HOME/.lttng
3924 */
3925 ret = asprintf(&rundir, DEFAULT_LTTNG_HOME_RUNDIR, home_path);
3926 if (ret < 0) {
3927 ret = -ENOMEM;
3928 goto error;
3929 }
3930
3931 ret = create_lttng_rundir(rundir);
3932 if (ret < 0) {
3933 goto error;
3934 }
3935
3936 if (strlen(apps_unix_sock_path) == 0) {
3937 snprintf(apps_unix_sock_path, PATH_MAX,
3938 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
3939 }
3940
3941 /* Set the cli tool unix socket path */
3942 if (strlen(client_unix_sock_path) == 0) {
3943 snprintf(client_unix_sock_path, PATH_MAX,
3944 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
3945 }
3946
3947 /* Set global SHM for ust */
3948 if (strlen(wait_shm_path) == 0) {
3949 snprintf(wait_shm_path, PATH_MAX,
3950 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
3951 }
3952
3953 /* Set health check Unix path */
3954 if (strlen(health_unix_sock_path) == 0) {
3955 snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
3956 DEFAULT_HOME_HEALTH_UNIX_SOCK, home_path);
3957 }
3958 }
3959
3960 /* Set consumer initial state */
3961 kernel_consumerd_state = CONSUMER_STOPPED;
3962 ust_consumerd_state = CONSUMER_STOPPED;
3963
3964 DBG("Client socket path %s", client_unix_sock_path);
3965 DBG("Application socket path %s", apps_unix_sock_path);
3966 DBG("LTTng run directory path: %s", rundir);
3967
3968 /* 32 bits consumerd path setup */
3969 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX,
3970 DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH, rundir);
3971 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX,
3972 DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH, rundir);
3973
3974 DBG2("UST consumer 32 bits err path: %s",
3975 ustconsumer32_data.err_unix_sock_path);
3976 DBG2("UST consumer 32 bits cmd path: %s",
3977 ustconsumer32_data.cmd_unix_sock_path);
3978
3979 /* 64 bits consumerd path setup */
3980 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX,
3981 DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH, rundir);
3982 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX,
3983 DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH, rundir);
3984
3985 DBG2("UST consumer 64 bits err path: %s",
3986 ustconsumer64_data.err_unix_sock_path);
3987 DBG2("UST consumer 64 bits cmd path: %s",
3988 ustconsumer64_data.cmd_unix_sock_path);
3989
3990 /*
3991 * See if daemon already exist.
3992 */
3993 if ((ret = check_existing_daemon()) < 0) {
3994 ERR("Already running daemon.\n");
3995 /*
3996 * We do not goto exit because we must not cleanup()
3997 * because a daemon is already running.
3998 */
3999 goto error;
4000 }
4001
4002 /*
4003 * Init UST app hash table. Alloc hash table before this point since
4004 * cleanup() can get called after that point.
4005 */
4006 ust_app_ht_alloc();
4007
4008 /* After this point, we can safely call cleanup() with "goto exit" */
4009
4010 /*
4011 * These actions must be executed as root. We do that *after* setting up
4012 * the sockets path because we MUST make the check for another daemon using
4013 * those paths *before* trying to set the kernel consumer sockets and init
4014 * kernel tracer.
4015 */
4016 if (is_root) {
4017 ret = set_consumer_sockets(&kconsumer_data, rundir);
4018 if (ret < 0) {
4019 goto exit;
4020 }
4021
4022 /* Setup kernel tracer */
4023 if (!opt_no_kernel) {
4024 init_kernel_tracer();
4025 }
4026
4027 /* Set ulimit for open files */
4028 set_ulimit();
4029 }
4030 /* init lttng_fd tracking must be done after set_ulimit. */
4031 lttng_fd_init();
4032
4033 ret = set_consumer_sockets(&ustconsumer64_data, rundir);
4034 if (ret < 0) {
4035 goto exit;
4036 }
4037
4038 ret = set_consumer_sockets(&ustconsumer32_data, rundir);
4039 if (ret < 0) {
4040 goto exit;
4041 }
4042
4043 if ((ret = set_signal_handler()) < 0) {
4044 goto exit;
4045 }
4046
4047 /* Setup the needed unix socket */
4048 if ((ret = init_daemon_socket()) < 0) {
4049 goto exit;
4050 }
4051
4052 /* Set credentials to socket */
4053 if (is_root && ((ret = set_permissions(rundir)) < 0)) {
4054 goto exit;
4055 }
4056
4057 /* Get parent pid if -S, --sig-parent is specified. */
4058 if (opt_sig_parent) {
4059 ppid = getppid();
4060 }
4061
4062 /* Setup the kernel pipe for waking up the kernel thread */
4063 if (is_root && !opt_no_kernel) {
4064 if ((ret = utils_create_pipe_cloexec(kernel_poll_pipe)) < 0) {
4065 goto exit;
4066 }
4067 }
4068
4069 /* Setup the thread apps communication pipe. */
4070 if ((ret = utils_create_pipe_cloexec(apps_cmd_pipe)) < 0) {
4071 goto exit;
4072 }
4073
4074 /* Init UST command queue. */
4075 cds_wfq_init(&ust_cmd_queue.queue);
4076
4077 /*
4078 * Get session list pointer. This pointer MUST NOT be free(). This list is
4079 * statically declared in session.c
4080 */
4081 session_list_ptr = session_get_list();
4082
4083 /* Set up max poll set size */
4084 lttng_poll_set_max_size();
4085
4086 cmd_init();
4087
4088 /* Init all health thread counters. */
4089 health_init(&health_thread_cmd);
4090 health_init(&health_thread_kernel);
4091 health_init(&health_thread_app_manage);
4092 health_init(&health_thread_app_reg);
4093
4094 /*
4095 * Init health counters of the consumer thread. We do a quick hack here to
4096 * the state of the consumer health is fine even if the thread is not
4097 * started. Once the thread starts, the health state is updated with a poll
4098 * value to set a health code path. This is simply to ease our life and has
4099 * no cost what so ever.
4100 */
4101 health_init(&kconsumer_data.health);
4102 health_poll_update(&kconsumer_data.health);
4103 health_init(&ustconsumer32_data.health);
4104 health_poll_update(&ustconsumer32_data.health);
4105 health_init(&ustconsumer64_data.health);
4106 health_poll_update(&ustconsumer64_data.health);
4107
4108 /* Check for the application socket timeout env variable. */
4109 env_app_timeout = getenv(DEFAULT_APP_SOCKET_TIMEOUT_ENV);
4110 if (env_app_timeout) {
4111 app_socket_timeout = atoi(env_app_timeout);
4112 } else {
4113 app_socket_timeout = DEFAULT_APP_SOCKET_RW_TIMEOUT;
4114 }
4115
4116 /* Create thread to manage the client socket */
4117 ret = pthread_create(&health_thread, NULL,
4118 thread_manage_health, (void *) NULL);
4119 if (ret != 0) {
4120 PERROR("pthread_create health");
4121 goto exit_health;
4122 }
4123
4124 /* Create thread to manage the client socket */
4125 ret = pthread_create(&client_thread, NULL,
4126 thread_manage_clients, (void *) NULL);
4127 if (ret != 0) {
4128 PERROR("pthread_create clients");
4129 goto exit_client;
4130 }
4131
4132 /* Create thread to dispatch registration */
4133 ret = pthread_create(&dispatch_thread, NULL,
4134 thread_dispatch_ust_registration, (void *) NULL);
4135 if (ret != 0) {
4136 PERROR("pthread_create dispatch");
4137 goto exit_dispatch;
4138 }
4139
4140 /* Create thread to manage application registration. */
4141 ret = pthread_create(&reg_apps_thread, NULL,
4142 thread_registration_apps, (void *) NULL);
4143 if (ret != 0) {
4144 PERROR("pthread_create registration");
4145 goto exit_reg_apps;
4146 }
4147
4148 /* Create thread to manage application socket */
4149 ret = pthread_create(&apps_thread, NULL,
4150 thread_manage_apps, (void *) NULL);
4151 if (ret != 0) {
4152 PERROR("pthread_create apps");
4153 goto exit_apps;
4154 }
4155
4156 /* Don't start this thread if kernel tracing is not requested nor root */
4157 if (is_root && !opt_no_kernel) {
4158 /* Create kernel thread to manage kernel event */
4159 ret = pthread_create(&kernel_thread, NULL,
4160 thread_manage_kernel, (void *) NULL);
4161 if (ret != 0) {
4162 PERROR("pthread_create kernel");
4163 goto exit_kernel;
4164 }
4165
4166 ret = pthread_join(kernel_thread, &status);
4167 if (ret != 0) {
4168 PERROR("pthread_join");
4169 goto error; /* join error, exit without cleanup */
4170 }
4171 }
4172
4173 exit_kernel:
4174 ret = pthread_join(apps_thread, &status);
4175 if (ret != 0) {
4176 PERROR("pthread_join");
4177 goto error; /* join error, exit without cleanup */
4178 }
4179
4180 exit_apps:
4181 ret = pthread_join(reg_apps_thread, &status);
4182 if (ret != 0) {
4183 PERROR("pthread_join");
4184 goto error; /* join error, exit without cleanup */
4185 }
4186
4187 exit_reg_apps:
4188 ret = pthread_join(dispatch_thread, &status);
4189 if (ret != 0) {
4190 PERROR("pthread_join");
4191 goto error; /* join error, exit without cleanup */
4192 }
4193
4194 exit_dispatch:
4195 ret = pthread_join(client_thread, &status);
4196 if (ret != 0) {
4197 PERROR("pthread_join");
4198 goto error; /* join error, exit without cleanup */
4199 }
4200
4201 ret = join_consumer_thread(&kconsumer_data);
4202 if (ret != 0) {
4203 PERROR("join_consumer");
4204 goto error; /* join error, exit without cleanup */
4205 }
4206
4207 ret = join_consumer_thread(&ustconsumer32_data);
4208 if (ret != 0) {
4209 PERROR("join_consumer ust32");
4210 goto error; /* join error, exit without cleanup */
4211 }
4212
4213 ret = join_consumer_thread(&ustconsumer64_data);
4214 if (ret != 0) {
4215 PERROR("join_consumer ust64");
4216 goto error; /* join error, exit without cleanup */
4217 }
4218
4219 exit_client:
4220 ret = pthread_join(health_thread, &status);
4221 if (ret != 0) {
4222 PERROR("pthread_join health thread");
4223 goto error; /* join error, exit without cleanup */
4224 }
4225
4226 exit_health:
4227 exit:
4228 /*
4229 * cleanup() is called when no other thread is running.
4230 */
4231 rcu_thread_online();
4232 cleanup();
4233 rcu_thread_offline();
4234 rcu_unregister_thread();
4235 if (!ret) {
4236 exit(EXIT_SUCCESS);
4237 }
4238 error:
4239 exit(EXIT_FAILURE);
4240 }
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