Fix: Conditionally disable test requiring shared libs
[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 "health.h"
63 #include "testpoint.h"
64
65 #define CONSUMERD_FILE "lttng-consumerd"
66
67 /* Const values */
68 const char default_home_dir[] = DEFAULT_HOME_DIR;
69 const char default_tracing_group[] = DEFAULT_TRACING_GROUP;
70 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
71 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
72
73 const char *progname;
74 const char *opt_tracing_group;
75 static const char *opt_pidfile;
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 /*
226 * Socket timeout for receiving and sending in seconds.
227 */
228 static int app_socket_timeout;
229
230 static
231 void setup_consumerd_path(void)
232 {
233 const char *bin, *libdir;
234
235 /*
236 * Allow INSTALL_BIN_PATH to be used as a target path for the
237 * native architecture size consumer if CONFIG_CONSUMER*_PATH
238 * has not been defined.
239 */
240 #if (CAA_BITS_PER_LONG == 32)
241 if (!consumerd32_bin[0]) {
242 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
243 }
244 if (!consumerd32_libdir[0]) {
245 consumerd32_libdir = INSTALL_LIB_PATH;
246 }
247 #elif (CAA_BITS_PER_LONG == 64)
248 if (!consumerd64_bin[0]) {
249 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
250 }
251 if (!consumerd64_libdir[0]) {
252 consumerd64_libdir = INSTALL_LIB_PATH;
253 }
254 #else
255 #error "Unknown bitness"
256 #endif
257
258 /*
259 * runtime env. var. overrides the build default.
260 */
261 bin = getenv("LTTNG_CONSUMERD32_BIN");
262 if (bin) {
263 consumerd32_bin = bin;
264 }
265 bin = getenv("LTTNG_CONSUMERD64_BIN");
266 if (bin) {
267 consumerd64_bin = bin;
268 }
269 libdir = getenv("LTTNG_CONSUMERD32_LIBDIR");
270 if (libdir) {
271 consumerd32_libdir = libdir;
272 }
273 libdir = getenv("LTTNG_CONSUMERD64_LIBDIR");
274 if (libdir) {
275 consumerd64_libdir = libdir;
276 }
277 }
278
279 /*
280 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
281 */
282 static int create_thread_poll_set(struct lttng_poll_event *events,
283 unsigned int size)
284 {
285 int ret;
286
287 if (events == NULL || size == 0) {
288 ret = -1;
289 goto error;
290 }
291
292 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
293 if (ret < 0) {
294 goto error;
295 }
296
297 /* Add quit pipe */
298 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
299 if (ret < 0) {
300 goto error;
301 }
302
303 return 0;
304
305 error:
306 return ret;
307 }
308
309 /*
310 * Check if the thread quit pipe was triggered.
311 *
312 * Return 1 if it was triggered else 0;
313 */
314 static int check_thread_quit_pipe(int fd, uint32_t events)
315 {
316 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
317 return 1;
318 }
319
320 return 0;
321 }
322
323 /*
324 * Return group ID of the tracing group or -1 if not found.
325 */
326 static gid_t allowed_group(void)
327 {
328 struct group *grp;
329
330 if (opt_tracing_group) {
331 grp = getgrnam(opt_tracing_group);
332 } else {
333 grp = getgrnam(default_tracing_group);
334 }
335 if (!grp) {
336 return -1;
337 } else {
338 return grp->gr_gid;
339 }
340 }
341
342 /*
343 * Init thread quit pipe.
344 *
345 * Return -1 on error or 0 if all pipes are created.
346 */
347 static int init_thread_quit_pipe(void)
348 {
349 int ret, i;
350
351 ret = pipe(thread_quit_pipe);
352 if (ret < 0) {
353 PERROR("thread quit pipe");
354 goto error;
355 }
356
357 for (i = 0; i < 2; i++) {
358 ret = fcntl(thread_quit_pipe[i], F_SETFD, FD_CLOEXEC);
359 if (ret < 0) {
360 PERROR("fcntl");
361 goto error;
362 }
363 }
364
365 error:
366 return ret;
367 }
368
369 /*
370 * Stop all threads by closing the thread quit pipe.
371 */
372 static void stop_threads(void)
373 {
374 int ret;
375
376 /* Stopping all threads */
377 DBG("Terminating all threads");
378 ret = notify_thread_pipe(thread_quit_pipe[1]);
379 if (ret < 0) {
380 ERR("write error on thread quit pipe");
381 }
382
383 /* Dispatch thread */
384 CMM_STORE_SHARED(dispatch_thread_exit, 1);
385 futex_nto1_wake(&ust_cmd_queue.futex);
386 }
387
388 /*
389 * Cleanup the daemon
390 */
391 static void cleanup(void)
392 {
393 int ret;
394 char *cmd = NULL;
395 struct ltt_session *sess, *stmp;
396
397 DBG("Cleaning up");
398
399 /* First thing first, stop all threads */
400 utils_close_pipe(thread_quit_pipe);
401
402 /*
403 * If opt_pidfile is undefined, the default file will be wiped when
404 * removing the rundir.
405 */
406 if (opt_pidfile) {
407 ret = remove(opt_pidfile);
408 if (ret < 0) {
409 PERROR("remove pidfile %s", opt_pidfile);
410 }
411 }
412
413 DBG("Removing %s directory", rundir);
414 ret = asprintf(&cmd, "rm -rf %s", rundir);
415 if (ret < 0) {
416 ERR("asprintf failed. Something is really wrong!");
417 }
418
419 /* Remove lttng run directory */
420 ret = system(cmd);
421 if (ret < 0) {
422 ERR("Unable to clean %s", rundir);
423 }
424 free(cmd);
425 free(rundir);
426
427 DBG("Cleaning up all sessions");
428
429 /* Destroy session list mutex */
430 if (session_list_ptr != NULL) {
431 pthread_mutex_destroy(&session_list_ptr->lock);
432
433 /* Cleanup ALL session */
434 cds_list_for_each_entry_safe(sess, stmp,
435 &session_list_ptr->head, list) {
436 cmd_destroy_session(sess, kernel_poll_pipe[1]);
437 }
438 }
439
440 DBG("Closing all UST sockets");
441 ust_app_clean_list();
442
443 if (is_root && !opt_no_kernel) {
444 DBG2("Closing kernel fd");
445 if (kernel_tracer_fd >= 0) {
446 ret = close(kernel_tracer_fd);
447 if (ret) {
448 PERROR("close");
449 }
450 }
451 DBG("Unloading kernel modules");
452 modprobe_remove_lttng_all();
453 }
454
455 /* <fun> */
456 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
457 "Matthew, BEET driven development works!%c[%dm",
458 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
459 /* </fun> */
460 }
461
462 /*
463 * Send data on a unix socket using the liblttsessiondcomm API.
464 *
465 * Return lttcomm error code.
466 */
467 static int send_unix_sock(int sock, void *buf, size_t len)
468 {
469 /* Check valid length */
470 if (len == 0) {
471 return -1;
472 }
473
474 return lttcomm_send_unix_sock(sock, buf, len);
475 }
476
477 /*
478 * Free memory of a command context structure.
479 */
480 static void clean_command_ctx(struct command_ctx **cmd_ctx)
481 {
482 DBG("Clean command context structure");
483 if (*cmd_ctx) {
484 if ((*cmd_ctx)->llm) {
485 free((*cmd_ctx)->llm);
486 }
487 if ((*cmd_ctx)->lsm) {
488 free((*cmd_ctx)->lsm);
489 }
490 free(*cmd_ctx);
491 *cmd_ctx = NULL;
492 }
493 }
494
495 /*
496 * Notify UST applications using the shm mmap futex.
497 */
498 static int notify_ust_apps(int active)
499 {
500 char *wait_shm_mmap;
501
502 DBG("Notifying applications of session daemon state: %d", active);
503
504 /* See shm.c for this call implying mmap, shm and futex calls */
505 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
506 if (wait_shm_mmap == NULL) {
507 goto error;
508 }
509
510 /* Wake waiting process */
511 futex_wait_update((int32_t *) wait_shm_mmap, active);
512
513 /* Apps notified successfully */
514 return 0;
515
516 error:
517 return -1;
518 }
519
520 /*
521 * Setup the outgoing data buffer for the response (llm) by allocating the
522 * right amount of memory and copying the original information from the lsm
523 * structure.
524 *
525 * Return total size of the buffer pointed by buf.
526 */
527 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
528 {
529 int ret, buf_size;
530
531 buf_size = size;
532
533 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
534 if (cmd_ctx->llm == NULL) {
535 PERROR("zmalloc");
536 ret = -ENOMEM;
537 goto error;
538 }
539
540 /* Copy common data */
541 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
542 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
543
544 cmd_ctx->llm->data_size = size;
545 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
546
547 return buf_size;
548
549 error:
550 return ret;
551 }
552
553 /*
554 * Update the kernel poll set of all channel fd available over all tracing
555 * session. Add the wakeup pipe at the end of the set.
556 */
557 static int update_kernel_poll(struct lttng_poll_event *events)
558 {
559 int ret;
560 struct ltt_session *session;
561 struct ltt_kernel_channel *channel;
562
563 DBG("Updating kernel poll set");
564
565 session_lock_list();
566 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
567 session_lock(session);
568 if (session->kernel_session == NULL) {
569 session_unlock(session);
570 continue;
571 }
572
573 cds_list_for_each_entry(channel,
574 &session->kernel_session->channel_list.head, list) {
575 /* Add channel fd to the kernel poll set */
576 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
577 if (ret < 0) {
578 session_unlock(session);
579 goto error;
580 }
581 DBG("Channel fd %d added to kernel set", channel->fd);
582 }
583 session_unlock(session);
584 }
585 session_unlock_list();
586
587 return 0;
588
589 error:
590 session_unlock_list();
591 return -1;
592 }
593
594 /*
595 * Find the channel fd from 'fd' over all tracing session. When found, check
596 * for new channel stream and send those stream fds to the kernel consumer.
597 *
598 * Useful for CPU hotplug feature.
599 */
600 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
601 {
602 int ret = 0;
603 struct ltt_session *session;
604 struct ltt_kernel_session *ksess;
605 struct ltt_kernel_channel *channel;
606
607 DBG("Updating kernel streams for channel fd %d", fd);
608
609 session_lock_list();
610 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
611 session_lock(session);
612 if (session->kernel_session == NULL) {
613 session_unlock(session);
614 continue;
615 }
616 ksess = session->kernel_session;
617
618 cds_list_for_each_entry(channel, &ksess->channel_list.head, list) {
619 if (channel->fd == fd) {
620 DBG("Channel found, updating kernel streams");
621 ret = kernel_open_channel_stream(channel);
622 if (ret < 0) {
623 goto error;
624 }
625
626 /*
627 * Have we already sent fds to the consumer? If yes, it means
628 * that tracing is started so it is safe to send our updated
629 * stream fds.
630 */
631 if (ksess->consumer_fds_sent == 1 && ksess->consumer != NULL) {
632 struct lttng_ht_iter iter;
633 struct consumer_socket *socket;
634
635 rcu_read_lock();
636 cds_lfht_for_each_entry(ksess->consumer->socks->ht,
637 &iter.iter, socket, node.node) {
638 /* Code flow error */
639 assert(socket->fd >= 0);
640
641 pthread_mutex_lock(socket->lock);
642 ret = kernel_consumer_send_channel_stream(socket,
643 channel, ksess);
644 pthread_mutex_unlock(socket->lock);
645 if (ret < 0) {
646 rcu_read_unlock();
647 goto error;
648 }
649 }
650 rcu_read_unlock();
651 }
652 goto error;
653 }
654 }
655 session_unlock(session);
656 }
657 session_unlock_list();
658 return ret;
659
660 error:
661 session_unlock(session);
662 session_unlock_list();
663 return ret;
664 }
665
666 /*
667 * For each tracing session, update newly registered apps.
668 */
669 static void update_ust_app(int app_sock)
670 {
671 struct ltt_session *sess, *stmp;
672
673 session_lock_list();
674
675 /* For all tracing session(s) */
676 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
677 session_lock(sess);
678 if (sess->ust_session) {
679 ust_app_global_update(sess->ust_session, app_sock);
680 }
681 session_unlock(sess);
682 }
683
684 session_unlock_list();
685 }
686
687 /*
688 * This thread manage event coming from the kernel.
689 *
690 * Features supported in this thread:
691 * -) CPU Hotplug
692 */
693 static void *thread_manage_kernel(void *data)
694 {
695 int ret, i, pollfd, update_poll_flag = 1, err = -1;
696 uint32_t revents, nb_fd;
697 char tmp;
698 struct lttng_poll_event events;
699
700 DBG("[thread] Thread manage kernel started");
701
702 health_register(HEALTH_TYPE_KERNEL);
703
704 /*
705 * This first step of the while is to clean this structure which could free
706 * non NULL pointers so zero it before the loop.
707 */
708 memset(&events, 0, sizeof(events));
709
710 if (testpoint(thread_manage_kernel)) {
711 goto error_testpoint;
712 }
713
714 health_code_update();
715
716 if (testpoint(thread_manage_kernel_before_loop)) {
717 goto error_testpoint;
718 }
719
720 while (1) {
721 health_code_update();
722
723 if (update_poll_flag == 1) {
724 /* Clean events object. We are about to populate it again. */
725 lttng_poll_clean(&events);
726
727 ret = create_thread_poll_set(&events, 2);
728 if (ret < 0) {
729 goto error_poll_create;
730 }
731
732 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
733 if (ret < 0) {
734 goto error;
735 }
736
737 /* This will add the available kernel channel if any. */
738 ret = update_kernel_poll(&events);
739 if (ret < 0) {
740 goto error;
741 }
742 update_poll_flag = 0;
743 }
744
745 DBG("Thread kernel polling on %d fds", LTTNG_POLL_GETNB(&events));
746
747 /* Poll infinite value of time */
748 restart:
749 health_poll_entry();
750 ret = lttng_poll_wait(&events, -1);
751 health_poll_exit();
752 if (ret < 0) {
753 /*
754 * Restart interrupted system call.
755 */
756 if (errno == EINTR) {
757 goto restart;
758 }
759 goto error;
760 } else if (ret == 0) {
761 /* Should not happen since timeout is infinite */
762 ERR("Return value of poll is 0 with an infinite timeout.\n"
763 "This should not have happened! Continuing...");
764 continue;
765 }
766
767 nb_fd = ret;
768
769 for (i = 0; i < nb_fd; i++) {
770 /* Fetch once the poll data */
771 revents = LTTNG_POLL_GETEV(&events, i);
772 pollfd = LTTNG_POLL_GETFD(&events, i);
773
774 health_code_update();
775
776 /* Thread quit pipe has been closed. Killing thread. */
777 ret = check_thread_quit_pipe(pollfd, revents);
778 if (ret) {
779 err = 0;
780 goto exit;
781 }
782
783 /* Check for data on kernel pipe */
784 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
785 do {
786 ret = read(kernel_poll_pipe[0], &tmp, 1);
787 } while (ret < 0 && errno == EINTR);
788 /*
789 * Ret value is useless here, if this pipe gets any actions an
790 * update is required anyway.
791 */
792 update_poll_flag = 1;
793 continue;
794 } else {
795 /*
796 * New CPU detected by the kernel. Adding kernel stream to
797 * kernel session and updating the kernel consumer
798 */
799 if (revents & LPOLLIN) {
800 ret = update_kernel_stream(&kconsumer_data, pollfd);
801 if (ret < 0) {
802 continue;
803 }
804 break;
805 /*
806 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
807 * and unregister kernel stream at this point.
808 */
809 }
810 }
811 }
812 }
813
814 exit:
815 error:
816 lttng_poll_clean(&events);
817 error_poll_create:
818 error_testpoint:
819 utils_close_pipe(kernel_poll_pipe);
820 kernel_poll_pipe[0] = kernel_poll_pipe[1] = -1;
821 if (err) {
822 health_error();
823 ERR("Health error occurred in %s", __func__);
824 WARN("Kernel thread died unexpectedly. "
825 "Kernel tracing can continue but CPU hotplug is disabled.");
826 }
827 health_unregister();
828 DBG("Kernel thread dying");
829 return NULL;
830 }
831
832 /*
833 * Signal pthread condition of the consumer data that the thread.
834 */
835 static void signal_consumer_condition(struct consumer_data *data, int state)
836 {
837 pthread_mutex_lock(&data->cond_mutex);
838
839 /*
840 * The state is set before signaling. It can be any value, it's the waiter
841 * job to correctly interpret this condition variable associated to the
842 * consumer pthread_cond.
843 *
844 * A value of 0 means that the corresponding thread of the consumer data
845 * was not started. 1 indicates that the thread has started and is ready
846 * for action. A negative value means that there was an error during the
847 * thread bootstrap.
848 */
849 data->consumer_thread_is_ready = state;
850 (void) pthread_cond_signal(&data->cond);
851
852 pthread_mutex_unlock(&data->cond_mutex);
853 }
854
855 /*
856 * This thread manage the consumer error sent back to the session daemon.
857 */
858 static void *thread_manage_consumer(void *data)
859 {
860 int sock = -1, i, ret, pollfd, err = -1;
861 uint32_t revents, nb_fd;
862 enum lttcomm_return_code code;
863 struct lttng_poll_event events;
864 struct consumer_data *consumer_data = data;
865
866 DBG("[thread] Manage consumer started");
867
868 health_register(HEALTH_TYPE_CONSUMER);
869
870 health_code_update();
871
872 /*
873 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
874 * Nothing more will be added to this poll set.
875 */
876 ret = create_thread_poll_set(&events, 2);
877 if (ret < 0) {
878 goto error_poll;
879 }
880
881 /*
882 * The error socket here is already in a listening state which was done
883 * just before spawning this thread to avoid a race between the consumer
884 * daemon exec trying to connect and the listen() call.
885 */
886 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
887 if (ret < 0) {
888 goto error;
889 }
890
891 health_code_update();
892
893 /* Inifinite blocking call, waiting for transmission */
894 restart:
895 health_poll_entry();
896
897 if (testpoint(thread_manage_consumer)) {
898 goto error;
899 }
900
901 ret = lttng_poll_wait(&events, -1);
902 health_poll_exit();
903 if (ret < 0) {
904 /*
905 * Restart interrupted system call.
906 */
907 if (errno == EINTR) {
908 goto restart;
909 }
910 goto error;
911 }
912
913 nb_fd = ret;
914
915 for (i = 0; i < nb_fd; i++) {
916 /* Fetch once the poll data */
917 revents = LTTNG_POLL_GETEV(&events, i);
918 pollfd = LTTNG_POLL_GETFD(&events, i);
919
920 health_code_update();
921
922 /* Thread quit pipe has been closed. Killing thread. */
923 ret = check_thread_quit_pipe(pollfd, revents);
924 if (ret) {
925 err = 0;
926 goto exit;
927 }
928
929 /* Event on the registration socket */
930 if (pollfd == consumer_data->err_sock) {
931 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
932 ERR("consumer err socket poll error");
933 goto error;
934 }
935 }
936 }
937
938 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
939 if (sock < 0) {
940 goto error;
941 }
942
943 /*
944 * Set the CLOEXEC flag. Return code is useless because either way, the
945 * show must go on.
946 */
947 (void) utils_set_fd_cloexec(sock);
948
949 health_code_update();
950
951 DBG2("Receiving code from consumer err_sock");
952
953 /* Getting status code from kconsumerd */
954 ret = lttcomm_recv_unix_sock(sock, &code,
955 sizeof(enum lttcomm_return_code));
956 if (ret <= 0) {
957 goto error;
958 }
959
960 health_code_update();
961
962 if (code == LTTCOMM_CONSUMERD_COMMAND_SOCK_READY) {
963 consumer_data->cmd_sock =
964 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
965 if (consumer_data->cmd_sock < 0) {
966 /* On error, signal condition and quit. */
967 signal_consumer_condition(consumer_data, -1);
968 PERROR("consumer connect");
969 goto error;
970 }
971 signal_consumer_condition(consumer_data, 1);
972 DBG("Consumer command socket ready");
973 } else {
974 ERR("consumer error when waiting for SOCK_READY : %s",
975 lttcomm_get_readable_code(-code));
976 goto error;
977 }
978
979 /* Remove the kconsumerd error sock since we've established a connexion */
980 ret = lttng_poll_del(&events, consumer_data->err_sock);
981 if (ret < 0) {
982 goto error;
983 }
984
985 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
986 if (ret < 0) {
987 goto error;
988 }
989
990 health_code_update();
991
992 /* Inifinite blocking call, waiting for transmission */
993 restart_poll:
994 health_poll_entry();
995 ret = lttng_poll_wait(&events, -1);
996 health_poll_exit();
997 if (ret < 0) {
998 /*
999 * Restart interrupted system call.
1000 */
1001 if (errno == EINTR) {
1002 goto restart_poll;
1003 }
1004 goto error;
1005 }
1006
1007 nb_fd = ret;
1008
1009 for (i = 0; i < nb_fd; i++) {
1010 /* Fetch once the poll data */
1011 revents = LTTNG_POLL_GETEV(&events, i);
1012 pollfd = LTTNG_POLL_GETFD(&events, i);
1013
1014 health_code_update();
1015
1016 /* Thread quit pipe has been closed. Killing thread. */
1017 ret = check_thread_quit_pipe(pollfd, revents);
1018 if (ret) {
1019 err = 0;
1020 goto exit;
1021 }
1022
1023 /* Event on the kconsumerd socket */
1024 if (pollfd == sock) {
1025 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1026 ERR("consumer err socket second poll error");
1027 goto error;
1028 }
1029 }
1030 }
1031
1032 health_code_update();
1033
1034 /* Wait for any kconsumerd error */
1035 ret = lttcomm_recv_unix_sock(sock, &code,
1036 sizeof(enum lttcomm_return_code));
1037 if (ret <= 0) {
1038 ERR("consumer closed the command socket");
1039 goto error;
1040 }
1041
1042 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1043
1044 exit:
1045 error:
1046 /* Immediately set the consumerd state to stopped */
1047 if (consumer_data->type == LTTNG_CONSUMER_KERNEL) {
1048 uatomic_set(&kernel_consumerd_state, CONSUMER_ERROR);
1049 } else if (consumer_data->type == LTTNG_CONSUMER64_UST ||
1050 consumer_data->type == LTTNG_CONSUMER32_UST) {
1051 uatomic_set(&ust_consumerd_state, CONSUMER_ERROR);
1052 } else {
1053 /* Code flow error... */
1054 assert(0);
1055 }
1056
1057 if (consumer_data->err_sock >= 0) {
1058 ret = close(consumer_data->err_sock);
1059 if (ret) {
1060 PERROR("close");
1061 }
1062 }
1063 if (consumer_data->cmd_sock >= 0) {
1064 ret = close(consumer_data->cmd_sock);
1065 if (ret) {
1066 PERROR("close");
1067 }
1068 }
1069 if (sock >= 0) {
1070 ret = close(sock);
1071 if (ret) {
1072 PERROR("close");
1073 }
1074 }
1075
1076 unlink(consumer_data->err_unix_sock_path);
1077 unlink(consumer_data->cmd_unix_sock_path);
1078 consumer_data->pid = 0;
1079
1080 lttng_poll_clean(&events);
1081 error_poll:
1082 if (err) {
1083 health_error();
1084 ERR("Health error occurred in %s", __func__);
1085 }
1086 health_unregister();
1087 DBG("consumer thread cleanup completed");
1088
1089 return NULL;
1090 }
1091
1092 /*
1093 * This thread manage application communication.
1094 */
1095 static void *thread_manage_apps(void *data)
1096 {
1097 int i, ret, pollfd, err = -1;
1098 uint32_t revents, nb_fd;
1099 struct ust_command ust_cmd;
1100 struct lttng_poll_event events;
1101
1102 DBG("[thread] Manage application started");
1103
1104 rcu_register_thread();
1105 rcu_thread_online();
1106
1107 health_register(HEALTH_TYPE_APP_MANAGE);
1108
1109 if (testpoint(thread_manage_apps)) {
1110 goto error_testpoint;
1111 }
1112
1113 health_code_update();
1114
1115 ret = create_thread_poll_set(&events, 2);
1116 if (ret < 0) {
1117 goto error_poll_create;
1118 }
1119
1120 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1121 if (ret < 0) {
1122 goto error;
1123 }
1124
1125 if (testpoint(thread_manage_apps_before_loop)) {
1126 goto error;
1127 }
1128
1129 health_code_update();
1130
1131 while (1) {
1132 DBG("Apps thread polling on %d fds", LTTNG_POLL_GETNB(&events));
1133
1134 /* Inifinite blocking call, waiting for transmission */
1135 restart:
1136 health_poll_entry();
1137 ret = lttng_poll_wait(&events, -1);
1138 health_poll_exit();
1139 if (ret < 0) {
1140 /*
1141 * Restart interrupted system call.
1142 */
1143 if (errno == EINTR) {
1144 goto restart;
1145 }
1146 goto error;
1147 }
1148
1149 nb_fd = ret;
1150
1151 for (i = 0; i < nb_fd; i++) {
1152 /* Fetch once the poll data */
1153 revents = LTTNG_POLL_GETEV(&events, i);
1154 pollfd = LTTNG_POLL_GETFD(&events, i);
1155
1156 health_code_update();
1157
1158 /* Thread quit pipe has been closed. Killing thread. */
1159 ret = check_thread_quit_pipe(pollfd, revents);
1160 if (ret) {
1161 err = 0;
1162 goto exit;
1163 }
1164
1165 /* Inspect the apps cmd pipe */
1166 if (pollfd == apps_cmd_pipe[0]) {
1167 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1168 ERR("Apps command pipe error");
1169 goto error;
1170 } else if (revents & LPOLLIN) {
1171 /* Empty pipe */
1172 do {
1173 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1174 } while (ret < 0 && errno == EINTR);
1175 if (ret < 0 || ret < sizeof(ust_cmd)) {
1176 PERROR("read apps cmd pipe");
1177 goto error;
1178 }
1179
1180 health_code_update();
1181
1182 /* Register applicaton to the session daemon */
1183 ret = ust_app_register(&ust_cmd.reg_msg,
1184 ust_cmd.sock);
1185 if (ret == -ENOMEM) {
1186 goto error;
1187 } else if (ret < 0) {
1188 break;
1189 }
1190
1191 health_code_update();
1192
1193 /*
1194 * Validate UST version compatibility.
1195 */
1196 ret = ust_app_validate_version(ust_cmd.sock);
1197 if (ret >= 0) {
1198 /*
1199 * Add channel(s) and event(s) to newly registered apps
1200 * from lttng global UST domain.
1201 */
1202 update_ust_app(ust_cmd.sock);
1203 }
1204
1205 health_code_update();
1206
1207 ret = ust_app_register_done(ust_cmd.sock);
1208 if (ret < 0) {
1209 /*
1210 * If the registration is not possible, we simply
1211 * unregister the apps and continue
1212 */
1213 ust_app_unregister(ust_cmd.sock);
1214 } else {
1215 /*
1216 * We only monitor the error events of the socket. This
1217 * thread does not handle any incoming data from UST
1218 * (POLLIN).
1219 */
1220 ret = lttng_poll_add(&events, ust_cmd.sock,
1221 LPOLLERR & LPOLLHUP & LPOLLRDHUP);
1222 if (ret < 0) {
1223 goto error;
1224 }
1225
1226 /* Set socket timeout for both receiving and ending */
1227 (void) lttcomm_setsockopt_rcv_timeout(ust_cmd.sock,
1228 app_socket_timeout);
1229 (void) lttcomm_setsockopt_snd_timeout(ust_cmd.sock,
1230 app_socket_timeout);
1231
1232 DBG("Apps with sock %d added to poll set",
1233 ust_cmd.sock);
1234 }
1235
1236 health_code_update();
1237
1238 break;
1239 }
1240 } else {
1241 /*
1242 * At this point, we know that a registered application made
1243 * the event at poll_wait.
1244 */
1245 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1246 /* Removing from the poll set */
1247 ret = lttng_poll_del(&events, pollfd);
1248 if (ret < 0) {
1249 goto error;
1250 }
1251
1252 /* Socket closed on remote end. */
1253 ust_app_unregister(pollfd);
1254 break;
1255 }
1256 }
1257
1258 health_code_update();
1259 }
1260 }
1261
1262 exit:
1263 error:
1264 lttng_poll_clean(&events);
1265 error_poll_create:
1266 error_testpoint:
1267 utils_close_pipe(apps_cmd_pipe);
1268 apps_cmd_pipe[0] = apps_cmd_pipe[1] = -1;
1269
1270 /*
1271 * We don't clean the UST app hash table here since already registered
1272 * applications can still be controlled so let them be until the session
1273 * daemon dies or the applications stop.
1274 */
1275
1276 if (err) {
1277 health_error();
1278 ERR("Health error occurred in %s", __func__);
1279 }
1280 health_unregister();
1281 DBG("Application communication apps thread cleanup complete");
1282 rcu_thread_offline();
1283 rcu_unregister_thread();
1284 return NULL;
1285 }
1286
1287 /*
1288 * Dispatch request from the registration threads to the application
1289 * communication thread.
1290 */
1291 static void *thread_dispatch_ust_registration(void *data)
1292 {
1293 int ret;
1294 struct cds_wfq_node *node;
1295 struct ust_command *ust_cmd = NULL;
1296
1297 DBG("[thread] Dispatch UST command started");
1298
1299 while (!CMM_LOAD_SHARED(dispatch_thread_exit)) {
1300 /* Atomically prepare the queue futex */
1301 futex_nto1_prepare(&ust_cmd_queue.futex);
1302
1303 do {
1304 /* Dequeue command for registration */
1305 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1306 if (node == NULL) {
1307 DBG("Woken up but nothing in the UST command queue");
1308 /* Continue thread execution */
1309 break;
1310 }
1311
1312 ust_cmd = caa_container_of(node, struct ust_command, node);
1313
1314 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1315 " gid:%d sock:%d name:%s (version %d.%d)",
1316 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1317 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1318 ust_cmd->sock, ust_cmd->reg_msg.name,
1319 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1320 /*
1321 * Inform apps thread of the new application registration. This
1322 * call is blocking so we can be assured that the data will be read
1323 * at some point in time or wait to the end of the world :)
1324 */
1325 if (apps_cmd_pipe[1] >= 0) {
1326 do {
1327 ret = write(apps_cmd_pipe[1], ust_cmd,
1328 sizeof(struct ust_command));
1329 } while (ret < 0 && errno == EINTR);
1330 if (ret < 0 || ret != sizeof(struct ust_command)) {
1331 PERROR("write apps cmd pipe");
1332 if (errno == EBADF) {
1333 /*
1334 * We can't inform the application thread to process
1335 * registration. We will exit or else application
1336 * registration will not occur and tracing will never
1337 * start.
1338 */
1339 goto error;
1340 }
1341 }
1342 } else {
1343 /* Application manager thread is not available. */
1344 ret = close(ust_cmd->sock);
1345 if (ret < 0) {
1346 PERROR("close ust_cmd sock");
1347 }
1348 }
1349 free(ust_cmd);
1350 } while (node != NULL);
1351
1352 /* Futex wait on queue. Blocking call on futex() */
1353 futex_nto1_wait(&ust_cmd_queue.futex);
1354 }
1355
1356 error:
1357 DBG("Dispatch thread dying");
1358 return NULL;
1359 }
1360
1361 /*
1362 * This thread manage application registration.
1363 */
1364 static void *thread_registration_apps(void *data)
1365 {
1366 int sock = -1, i, ret, pollfd, err = -1;
1367 uint32_t revents, nb_fd;
1368 struct lttng_poll_event events;
1369 /*
1370 * Get allocated in this thread, enqueued to a global queue, dequeued and
1371 * freed in the manage apps thread.
1372 */
1373 struct ust_command *ust_cmd = NULL;
1374
1375 DBG("[thread] Manage application registration started");
1376
1377 health_register(HEALTH_TYPE_APP_REG);
1378
1379 if (testpoint(thread_registration_apps)) {
1380 goto error_testpoint;
1381 }
1382
1383 ret = lttcomm_listen_unix_sock(apps_sock);
1384 if (ret < 0) {
1385 goto error_listen;
1386 }
1387
1388 /*
1389 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1390 * more will be added to this poll set.
1391 */
1392 ret = create_thread_poll_set(&events, 2);
1393 if (ret < 0) {
1394 goto error_create_poll;
1395 }
1396
1397 /* Add the application registration socket */
1398 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1399 if (ret < 0) {
1400 goto error_poll_add;
1401 }
1402
1403 /* Notify all applications to register */
1404 ret = notify_ust_apps(1);
1405 if (ret < 0) {
1406 ERR("Failed to notify applications or create the wait shared memory.\n"
1407 "Execution continues but there might be problem for already\n"
1408 "running applications that wishes to register.");
1409 }
1410
1411 while (1) {
1412 DBG("Accepting application registration");
1413
1414 /* Inifinite blocking call, waiting for transmission */
1415 restart:
1416 health_poll_entry();
1417 ret = lttng_poll_wait(&events, -1);
1418 health_poll_exit();
1419 if (ret < 0) {
1420 /*
1421 * Restart interrupted system call.
1422 */
1423 if (errno == EINTR) {
1424 goto restart;
1425 }
1426 goto error;
1427 }
1428
1429 nb_fd = ret;
1430
1431 for (i = 0; i < nb_fd; i++) {
1432 health_code_update();
1433
1434 /* Fetch once the poll data */
1435 revents = LTTNG_POLL_GETEV(&events, i);
1436 pollfd = LTTNG_POLL_GETFD(&events, i);
1437
1438 /* Thread quit pipe has been closed. Killing thread. */
1439 ret = check_thread_quit_pipe(pollfd, revents);
1440 if (ret) {
1441 err = 0;
1442 goto exit;
1443 }
1444
1445 /* Event on the registration socket */
1446 if (pollfd == apps_sock) {
1447 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1448 ERR("Register apps socket poll error");
1449 goto error;
1450 } else if (revents & LPOLLIN) {
1451 sock = lttcomm_accept_unix_sock(apps_sock);
1452 if (sock < 0) {
1453 goto error;
1454 }
1455
1456 /*
1457 * Set the CLOEXEC flag. Return code is useless because
1458 * either way, the show must go on.
1459 */
1460 (void) utils_set_fd_cloexec(sock);
1461
1462 /* Create UST registration command for enqueuing */
1463 ust_cmd = zmalloc(sizeof(struct ust_command));
1464 if (ust_cmd == NULL) {
1465 PERROR("ust command zmalloc");
1466 goto error;
1467 }
1468
1469 /*
1470 * Using message-based transmissions to ensure we don't
1471 * have to deal with partially received messages.
1472 */
1473 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
1474 if (ret < 0) {
1475 ERR("Exhausted file descriptors allowed for applications.");
1476 free(ust_cmd);
1477 ret = close(sock);
1478 if (ret) {
1479 PERROR("close");
1480 }
1481 sock = -1;
1482 continue;
1483 }
1484 health_code_update();
1485 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1486 sizeof(struct ust_register_msg));
1487 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1488 if (ret < 0) {
1489 PERROR("lttcomm_recv_unix_sock register apps");
1490 } else {
1491 ERR("Wrong size received on apps register");
1492 }
1493 free(ust_cmd);
1494 ret = close(sock);
1495 if (ret) {
1496 PERROR("close");
1497 }
1498 lttng_fd_put(LTTNG_FD_APPS, 1);
1499 sock = -1;
1500 continue;
1501 }
1502 health_code_update();
1503
1504 ust_cmd->sock = sock;
1505 sock = -1;
1506
1507 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1508 " gid:%d sock:%d name:%s (version %d.%d)",
1509 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1510 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1511 ust_cmd->sock, ust_cmd->reg_msg.name,
1512 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1513
1514 /*
1515 * Lock free enqueue the registration request. The red pill
1516 * has been taken! This apps will be part of the *system*.
1517 */
1518 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1519
1520 /*
1521 * Wake the registration queue futex. Implicit memory
1522 * barrier with the exchange in cds_wfq_enqueue.
1523 */
1524 futex_nto1_wake(&ust_cmd_queue.futex);
1525 }
1526 }
1527 }
1528 }
1529
1530 exit:
1531 error:
1532 if (err) {
1533 health_error();
1534 ERR("Health error occurred in %s", __func__);
1535 }
1536
1537 /* Notify that the registration thread is gone */
1538 notify_ust_apps(0);
1539
1540 if (apps_sock >= 0) {
1541 ret = close(apps_sock);
1542 if (ret) {
1543 PERROR("close");
1544 }
1545 }
1546 if (sock >= 0) {
1547 ret = close(sock);
1548 if (ret) {
1549 PERROR("close");
1550 }
1551 lttng_fd_put(LTTNG_FD_APPS, 1);
1552 }
1553 unlink(apps_unix_sock_path);
1554
1555 error_poll_add:
1556 lttng_poll_clean(&events);
1557 error_listen:
1558 error_create_poll:
1559 error_testpoint:
1560 DBG("UST Registration thread cleanup complete");
1561 health_unregister();
1562
1563 return NULL;
1564 }
1565
1566 /*
1567 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1568 * exec or it will fails.
1569 */
1570 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1571 {
1572 int ret, clock_ret;
1573 struct timespec timeout;
1574
1575 /* Make sure we set the readiness flag to 0 because we are NOT ready */
1576 consumer_data->consumer_thread_is_ready = 0;
1577
1578 /* Setup pthread condition */
1579 ret = pthread_condattr_init(&consumer_data->condattr);
1580 if (ret != 0) {
1581 errno = ret;
1582 PERROR("pthread_condattr_init consumer data");
1583 goto error;
1584 }
1585
1586 /*
1587 * Set the monotonic clock in order to make sure we DO NOT jump in time
1588 * between the clock_gettime() call and the timedwait call. See bug #324
1589 * for a more details and how we noticed it.
1590 */
1591 ret = pthread_condattr_setclock(&consumer_data->condattr, CLOCK_MONOTONIC);
1592 if (ret != 0) {
1593 errno = ret;
1594 PERROR("pthread_condattr_setclock consumer data");
1595 goto error;
1596 }
1597
1598 ret = pthread_cond_init(&consumer_data->cond, &consumer_data->condattr);
1599 if (ret != 0) {
1600 errno = ret;
1601 PERROR("pthread_cond_init consumer data");
1602 goto error;
1603 }
1604
1605 ret = pthread_create(&consumer_data->thread, NULL, thread_manage_consumer,
1606 consumer_data);
1607 if (ret != 0) {
1608 PERROR("pthread_create consumer");
1609 ret = -1;
1610 goto error;
1611 }
1612
1613 /* We are about to wait on a pthread condition */
1614 pthread_mutex_lock(&consumer_data->cond_mutex);
1615
1616 /* Get time for sem_timedwait absolute timeout */
1617 clock_ret = clock_gettime(CLOCK_MONOTONIC, &timeout);
1618 /*
1619 * Set the timeout for the condition timed wait even if the clock gettime
1620 * call fails since we might loop on that call and we want to avoid to
1621 * increment the timeout too many times.
1622 */
1623 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1624
1625 /*
1626 * The following loop COULD be skipped in some conditions so this is why we
1627 * set ret to 0 in order to make sure at least one round of the loop is
1628 * done.
1629 */
1630 ret = 0;
1631
1632 /*
1633 * Loop until the condition is reached or when a timeout is reached. Note
1634 * that the pthread_cond_timedwait(P) man page specifies that EINTR can NOT
1635 * be returned but the pthread_cond(3), from the glibc-doc, says that it is
1636 * possible. This loop does not take any chances and works with both of
1637 * them.
1638 */
1639 while (!consumer_data->consumer_thread_is_ready && ret != ETIMEDOUT) {
1640 if (clock_ret < 0) {
1641 PERROR("clock_gettime spawn consumer");
1642 /* Infinite wait for the consumerd thread to be ready */
1643 ret = pthread_cond_wait(&consumer_data->cond,
1644 &consumer_data->cond_mutex);
1645 } else {
1646 ret = pthread_cond_timedwait(&consumer_data->cond,
1647 &consumer_data->cond_mutex, &timeout);
1648 }
1649 }
1650
1651 /* Release the pthread condition */
1652 pthread_mutex_unlock(&consumer_data->cond_mutex);
1653
1654 if (ret != 0) {
1655 errno = ret;
1656 if (ret == ETIMEDOUT) {
1657 /*
1658 * Call has timed out so we kill the kconsumerd_thread and return
1659 * an error.
1660 */
1661 ERR("Condition timed out. The consumer thread was never ready."
1662 " Killing it");
1663 ret = pthread_cancel(consumer_data->thread);
1664 if (ret < 0) {
1665 PERROR("pthread_cancel consumer thread");
1666 }
1667 } else {
1668 PERROR("pthread_cond_wait failed consumer thread");
1669 }
1670 goto error;
1671 }
1672
1673 pthread_mutex_lock(&consumer_data->pid_mutex);
1674 if (consumer_data->pid == 0) {
1675 ERR("Consumerd did not start");
1676 pthread_mutex_unlock(&consumer_data->pid_mutex);
1677 goto error;
1678 }
1679 pthread_mutex_unlock(&consumer_data->pid_mutex);
1680
1681 return 0;
1682
1683 error:
1684 return ret;
1685 }
1686
1687 /*
1688 * Join consumer thread
1689 */
1690 static int join_consumer_thread(struct consumer_data *consumer_data)
1691 {
1692 void *status;
1693
1694 /* Consumer pid must be a real one. */
1695 if (consumer_data->pid > 0) {
1696 int ret;
1697 ret = kill(consumer_data->pid, SIGTERM);
1698 if (ret) {
1699 ERR("Error killing consumer daemon");
1700 return ret;
1701 }
1702 return pthread_join(consumer_data->thread, &status);
1703 } else {
1704 return 0;
1705 }
1706 }
1707
1708 /*
1709 * Fork and exec a consumer daemon (consumerd).
1710 *
1711 * Return pid if successful else -1.
1712 */
1713 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1714 {
1715 int ret;
1716 pid_t pid;
1717 const char *consumer_to_use;
1718 const char *verbosity;
1719 struct stat st;
1720
1721 DBG("Spawning consumerd");
1722
1723 pid = fork();
1724 if (pid == 0) {
1725 /*
1726 * Exec consumerd.
1727 */
1728 if (opt_verbose_consumer) {
1729 verbosity = "--verbose";
1730 } else {
1731 verbosity = "--quiet";
1732 }
1733 switch (consumer_data->type) {
1734 case LTTNG_CONSUMER_KERNEL:
1735 /*
1736 * Find out which consumerd to execute. We will first try the
1737 * 64-bit path, then the sessiond's installation directory, and
1738 * fallback on the 32-bit one,
1739 */
1740 DBG3("Looking for a kernel consumer at these locations:");
1741 DBG3(" 1) %s", consumerd64_bin);
1742 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1743 DBG3(" 3) %s", consumerd32_bin);
1744 if (stat(consumerd64_bin, &st) == 0) {
1745 DBG3("Found location #1");
1746 consumer_to_use = consumerd64_bin;
1747 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1748 DBG3("Found location #2");
1749 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1750 } else if (stat(consumerd32_bin, &st) == 0) {
1751 DBG3("Found location #3");
1752 consumer_to_use = consumerd32_bin;
1753 } else {
1754 DBG("Could not find any valid consumerd executable");
1755 break;
1756 }
1757 DBG("Using kernel consumer at: %s", consumer_to_use);
1758 execl(consumer_to_use,
1759 "lttng-consumerd", verbosity, "-k",
1760 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1761 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1762 NULL);
1763 break;
1764 case LTTNG_CONSUMER64_UST:
1765 {
1766 char *tmpnew = NULL;
1767
1768 if (consumerd64_libdir[0] != '\0') {
1769 char *tmp;
1770 size_t tmplen;
1771
1772 tmp = getenv("LD_LIBRARY_PATH");
1773 if (!tmp) {
1774 tmp = "";
1775 }
1776 tmplen = strlen("LD_LIBRARY_PATH=")
1777 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1778 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1779 if (!tmpnew) {
1780 ret = -ENOMEM;
1781 goto error;
1782 }
1783 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1784 strcat(tmpnew, consumerd64_libdir);
1785 if (tmp[0] != '\0') {
1786 strcat(tmpnew, ":");
1787 strcat(tmpnew, tmp);
1788 }
1789 ret = putenv(tmpnew);
1790 if (ret) {
1791 ret = -errno;
1792 goto error;
1793 }
1794 }
1795 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1796 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1797 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1798 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1799 NULL);
1800 if (consumerd64_libdir[0] != '\0') {
1801 free(tmpnew);
1802 }
1803 if (ret) {
1804 goto error;
1805 }
1806 break;
1807 }
1808 case LTTNG_CONSUMER32_UST:
1809 {
1810 char *tmpnew = NULL;
1811
1812 if (consumerd32_libdir[0] != '\0') {
1813 char *tmp;
1814 size_t tmplen;
1815
1816 tmp = getenv("LD_LIBRARY_PATH");
1817 if (!tmp) {
1818 tmp = "";
1819 }
1820 tmplen = strlen("LD_LIBRARY_PATH=")
1821 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1822 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1823 if (!tmpnew) {
1824 ret = -ENOMEM;
1825 goto error;
1826 }
1827 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1828 strcat(tmpnew, consumerd32_libdir);
1829 if (tmp[0] != '\0') {
1830 strcat(tmpnew, ":");
1831 strcat(tmpnew, tmp);
1832 }
1833 ret = putenv(tmpnew);
1834 if (ret) {
1835 ret = -errno;
1836 goto error;
1837 }
1838 }
1839 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1840 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1841 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1842 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1843 NULL);
1844 if (consumerd32_libdir[0] != '\0') {
1845 free(tmpnew);
1846 }
1847 if (ret) {
1848 goto error;
1849 }
1850 break;
1851 }
1852 default:
1853 PERROR("unknown consumer type");
1854 exit(EXIT_FAILURE);
1855 }
1856 if (errno != 0) {
1857 PERROR("kernel start consumer exec");
1858 }
1859 exit(EXIT_FAILURE);
1860 } else if (pid > 0) {
1861 ret = pid;
1862 } else {
1863 PERROR("start consumer fork");
1864 ret = -errno;
1865 }
1866 error:
1867 return ret;
1868 }
1869
1870 /*
1871 * Spawn the consumerd daemon and session daemon thread.
1872 */
1873 static int start_consumerd(struct consumer_data *consumer_data)
1874 {
1875 int ret;
1876
1877 /*
1878 * Set the listen() state on the socket since there is a possible race
1879 * between the exec() of the consumer daemon and this call if place in the
1880 * consumer thread. See bug #366 for more details.
1881 */
1882 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
1883 if (ret < 0) {
1884 goto error;
1885 }
1886
1887 pthread_mutex_lock(&consumer_data->pid_mutex);
1888 if (consumer_data->pid != 0) {
1889 pthread_mutex_unlock(&consumer_data->pid_mutex);
1890 goto end;
1891 }
1892
1893 ret = spawn_consumerd(consumer_data);
1894 if (ret < 0) {
1895 ERR("Spawning consumerd failed");
1896 pthread_mutex_unlock(&consumer_data->pid_mutex);
1897 goto error;
1898 }
1899
1900 /* Setting up the consumer_data pid */
1901 consumer_data->pid = ret;
1902 DBG2("Consumer pid %d", consumer_data->pid);
1903 pthread_mutex_unlock(&consumer_data->pid_mutex);
1904
1905 DBG2("Spawning consumer control thread");
1906 ret = spawn_consumer_thread(consumer_data);
1907 if (ret < 0) {
1908 ERR("Fatal error spawning consumer control thread");
1909 goto error;
1910 }
1911
1912 end:
1913 return 0;
1914
1915 error:
1916 /* Cleanup already created socket on error. */
1917 if (consumer_data->err_sock >= 0) {
1918 int err;
1919
1920 err = close(consumer_data->err_sock);
1921 if (err < 0) {
1922 PERROR("close consumer data error socket");
1923 }
1924 }
1925 return ret;
1926 }
1927
1928 /*
1929 * Compute health status of each consumer. If one of them is zero (bad
1930 * state), we return 0.
1931 */
1932 static int check_consumer_health(void)
1933 {
1934 int ret;
1935
1936 ret = health_check_state(HEALTH_TYPE_CONSUMER);
1937
1938 DBG3("Health consumer check %d", ret);
1939
1940 return ret;
1941 }
1942
1943 /*
1944 * Setup necessary data for kernel tracer action.
1945 */
1946 static int init_kernel_tracer(void)
1947 {
1948 int ret;
1949
1950 /* Modprobe lttng kernel modules */
1951 ret = modprobe_lttng_control();
1952 if (ret < 0) {
1953 goto error;
1954 }
1955
1956 /* Open debugfs lttng */
1957 kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
1958 if (kernel_tracer_fd < 0) {
1959 DBG("Failed to open %s", module_proc_lttng);
1960 ret = -1;
1961 goto error_open;
1962 }
1963
1964 /* Validate kernel version */
1965 ret = kernel_validate_version(kernel_tracer_fd);
1966 if (ret < 0) {
1967 goto error_version;
1968 }
1969
1970 ret = modprobe_lttng_data();
1971 if (ret < 0) {
1972 goto error_modules;
1973 }
1974
1975 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1976 return 0;
1977
1978 error_version:
1979 modprobe_remove_lttng_control();
1980 ret = close(kernel_tracer_fd);
1981 if (ret) {
1982 PERROR("close");
1983 }
1984 kernel_tracer_fd = -1;
1985 return LTTNG_ERR_KERN_VERSION;
1986
1987 error_modules:
1988 ret = close(kernel_tracer_fd);
1989 if (ret) {
1990 PERROR("close");
1991 }
1992
1993 error_open:
1994 modprobe_remove_lttng_control();
1995
1996 error:
1997 WARN("No kernel tracer available");
1998 kernel_tracer_fd = -1;
1999 if (!is_root) {
2000 return LTTNG_ERR_NEED_ROOT_SESSIOND;
2001 } else {
2002 return LTTNG_ERR_KERN_NA;
2003 }
2004 }
2005
2006
2007 /*
2008 * Copy consumer output from the tracing session to the domain session. The
2009 * function also applies the right modification on a per domain basis for the
2010 * trace files destination directory.
2011 */
2012 static int copy_session_consumer(int domain, struct ltt_session *session)
2013 {
2014 int ret;
2015 const char *dir_name;
2016 struct consumer_output *consumer;
2017
2018 assert(session);
2019 assert(session->consumer);
2020
2021 switch (domain) {
2022 case LTTNG_DOMAIN_KERNEL:
2023 DBG3("Copying tracing session consumer output in kernel session");
2024 /*
2025 * XXX: We should audit the session creation and what this function
2026 * does "extra" in order to avoid a destroy since this function is used
2027 * in the domain session creation (kernel and ust) only. Same for UST
2028 * domain.
2029 */
2030 if (session->kernel_session->consumer) {
2031 consumer_destroy_output(session->kernel_session->consumer);
2032 }
2033 session->kernel_session->consumer =
2034 consumer_copy_output(session->consumer);
2035 /* Ease our life a bit for the next part */
2036 consumer = session->kernel_session->consumer;
2037 dir_name = DEFAULT_KERNEL_TRACE_DIR;
2038 break;
2039 case LTTNG_DOMAIN_UST:
2040 DBG3("Copying tracing session consumer output in UST session");
2041 if (session->ust_session->consumer) {
2042 consumer_destroy_output(session->ust_session->consumer);
2043 }
2044 session->ust_session->consumer =
2045 consumer_copy_output(session->consumer);
2046 /* Ease our life a bit for the next part */
2047 consumer = session->ust_session->consumer;
2048 dir_name = DEFAULT_UST_TRACE_DIR;
2049 break;
2050 default:
2051 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
2052 goto error;
2053 }
2054
2055 /* Append correct directory to subdir */
2056 strncat(consumer->subdir, dir_name,
2057 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
2058 DBG3("Copy session consumer subdir %s", consumer->subdir);
2059
2060 ret = LTTNG_OK;
2061
2062 error:
2063 return ret;
2064 }
2065
2066 /*
2067 * Create an UST session and add it to the session ust list.
2068 */
2069 static int create_ust_session(struct ltt_session *session,
2070 struct lttng_domain *domain)
2071 {
2072 int ret;
2073 struct ltt_ust_session *lus = NULL;
2074
2075 assert(session);
2076 assert(domain);
2077 assert(session->consumer);
2078
2079 switch (domain->type) {
2080 case LTTNG_DOMAIN_UST:
2081 break;
2082 default:
2083 ERR("Unknown UST domain on create session %d", domain->type);
2084 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
2085 goto error;
2086 }
2087
2088 DBG("Creating UST session");
2089
2090 lus = trace_ust_create_session(session->path, session->id);
2091 if (lus == NULL) {
2092 ret = LTTNG_ERR_UST_SESS_FAIL;
2093 goto error;
2094 }
2095
2096 lus->uid = session->uid;
2097 lus->gid = session->gid;
2098 session->ust_session = lus;
2099
2100 /* Copy session output to the newly created UST session */
2101 ret = copy_session_consumer(domain->type, session);
2102 if (ret != LTTNG_OK) {
2103 goto error;
2104 }
2105
2106 return LTTNG_OK;
2107
2108 error:
2109 free(lus);
2110 session->ust_session = NULL;
2111 return ret;
2112 }
2113
2114 /*
2115 * Create a kernel tracer session then create the default channel.
2116 */
2117 static int create_kernel_session(struct ltt_session *session)
2118 {
2119 int ret;
2120
2121 DBG("Creating kernel session");
2122
2123 ret = kernel_create_session(session, kernel_tracer_fd);
2124 if (ret < 0) {
2125 ret = LTTNG_ERR_KERN_SESS_FAIL;
2126 goto error;
2127 }
2128
2129 /* Code flow safety */
2130 assert(session->kernel_session);
2131
2132 /* Copy session output to the newly created Kernel session */
2133 ret = copy_session_consumer(LTTNG_DOMAIN_KERNEL, session);
2134 if (ret != LTTNG_OK) {
2135 goto error;
2136 }
2137
2138 /* Create directory(ies) on local filesystem. */
2139 if (session->kernel_session->consumer->type == CONSUMER_DST_LOCAL &&
2140 strlen(session->kernel_session->consumer->dst.trace_path) > 0) {
2141 ret = run_as_mkdir_recursive(
2142 session->kernel_session->consumer->dst.trace_path,
2143 S_IRWXU | S_IRWXG, session->uid, session->gid);
2144 if (ret < 0) {
2145 if (ret != -EEXIST) {
2146 ERR("Trace directory creation error");
2147 goto error;
2148 }
2149 }
2150 }
2151
2152 session->kernel_session->uid = session->uid;
2153 session->kernel_session->gid = session->gid;
2154
2155 return LTTNG_OK;
2156
2157 error:
2158 trace_kernel_destroy_session(session->kernel_session);
2159 session->kernel_session = NULL;
2160 return ret;
2161 }
2162
2163 /*
2164 * Count number of session permitted by uid/gid.
2165 */
2166 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
2167 {
2168 unsigned int i = 0;
2169 struct ltt_session *session;
2170
2171 DBG("Counting number of available session for UID %d GID %d",
2172 uid, gid);
2173 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2174 /*
2175 * Only list the sessions the user can control.
2176 */
2177 if (!session_access_ok(session, uid, gid)) {
2178 continue;
2179 }
2180 i++;
2181 }
2182 return i;
2183 }
2184
2185 /*
2186 * Process the command requested by the lttng client within the command
2187 * context structure. This function make sure that the return structure (llm)
2188 * is set and ready for transmission before returning.
2189 *
2190 * Return any error encountered or 0 for success.
2191 *
2192 * "sock" is only used for special-case var. len data.
2193 */
2194 static int process_client_msg(struct command_ctx *cmd_ctx, int sock,
2195 int *sock_error)
2196 {
2197 int ret = LTTNG_OK;
2198 int need_tracing_session = 1;
2199 int need_domain;
2200
2201 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
2202
2203 *sock_error = 0;
2204
2205 switch (cmd_ctx->lsm->cmd_type) {
2206 case LTTNG_CREATE_SESSION:
2207 case LTTNG_DESTROY_SESSION:
2208 case LTTNG_LIST_SESSIONS:
2209 case LTTNG_LIST_DOMAINS:
2210 case LTTNG_START_TRACE:
2211 case LTTNG_STOP_TRACE:
2212 case LTTNG_DATA_PENDING:
2213 need_domain = 0;
2214 break;
2215 default:
2216 need_domain = 1;
2217 }
2218
2219 if (opt_no_kernel && need_domain
2220 && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
2221 if (!is_root) {
2222 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
2223 } else {
2224 ret = LTTNG_ERR_KERN_NA;
2225 }
2226 goto error;
2227 }
2228
2229 /* Deny register consumer if we already have a spawned consumer. */
2230 if (cmd_ctx->lsm->cmd_type == LTTNG_REGISTER_CONSUMER) {
2231 pthread_mutex_lock(&kconsumer_data.pid_mutex);
2232 if (kconsumer_data.pid > 0) {
2233 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2234 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2235 goto error;
2236 }
2237 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2238 }
2239
2240 /*
2241 * Check for command that don't needs to allocate a returned payload. We do
2242 * this here so we don't have to make the call for no payload at each
2243 * command.
2244 */
2245 switch(cmd_ctx->lsm->cmd_type) {
2246 case LTTNG_LIST_SESSIONS:
2247 case LTTNG_LIST_TRACEPOINTS:
2248 case LTTNG_LIST_TRACEPOINT_FIELDS:
2249 case LTTNG_LIST_DOMAINS:
2250 case LTTNG_LIST_CHANNELS:
2251 case LTTNG_LIST_EVENTS:
2252 break;
2253 default:
2254 /* Setup lttng message with no payload */
2255 ret = setup_lttng_msg(cmd_ctx, 0);
2256 if (ret < 0) {
2257 /* This label does not try to unlock the session */
2258 goto init_setup_error;
2259 }
2260 }
2261
2262 /* Commands that DO NOT need a session. */
2263 switch (cmd_ctx->lsm->cmd_type) {
2264 case LTTNG_CREATE_SESSION:
2265 case LTTNG_CALIBRATE:
2266 case LTTNG_LIST_SESSIONS:
2267 case LTTNG_LIST_TRACEPOINTS:
2268 case LTTNG_LIST_TRACEPOINT_FIELDS:
2269 need_tracing_session = 0;
2270 break;
2271 default:
2272 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
2273 /*
2274 * We keep the session list lock across _all_ commands
2275 * for now, because the per-session lock does not
2276 * handle teardown properly.
2277 */
2278 session_lock_list();
2279 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
2280 if (cmd_ctx->session == NULL) {
2281 if (cmd_ctx->lsm->session.name != NULL) {
2282 ret = LTTNG_ERR_SESS_NOT_FOUND;
2283 } else {
2284 /* If no session name specified */
2285 ret = LTTNG_ERR_SELECT_SESS;
2286 }
2287 goto error;
2288 } else {
2289 /* Acquire lock for the session */
2290 session_lock(cmd_ctx->session);
2291 }
2292 break;
2293 }
2294
2295 if (!need_domain) {
2296 goto skip_domain;
2297 }
2298
2299 /*
2300 * Check domain type for specific "pre-action".
2301 */
2302 switch (cmd_ctx->lsm->domain.type) {
2303 case LTTNG_DOMAIN_KERNEL:
2304 if (!is_root) {
2305 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
2306 goto error;
2307 }
2308
2309 /* Kernel tracer check */
2310 if (kernel_tracer_fd == -1) {
2311 /* Basically, load kernel tracer modules */
2312 ret = init_kernel_tracer();
2313 if (ret != 0) {
2314 goto error;
2315 }
2316 }
2317
2318 /* Consumer is in an ERROR state. Report back to client */
2319 if (uatomic_read(&kernel_consumerd_state) == CONSUMER_ERROR) {
2320 ret = LTTNG_ERR_NO_KERNCONSUMERD;
2321 goto error;
2322 }
2323
2324 /* Need a session for kernel command */
2325 if (need_tracing_session) {
2326 if (cmd_ctx->session->kernel_session == NULL) {
2327 ret = create_kernel_session(cmd_ctx->session);
2328 if (ret < 0) {
2329 ret = LTTNG_ERR_KERN_SESS_FAIL;
2330 goto error;
2331 }
2332 }
2333
2334 /* Start the kernel consumer daemon */
2335 pthread_mutex_lock(&kconsumer_data.pid_mutex);
2336 if (kconsumer_data.pid == 0 &&
2337 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER &&
2338 cmd_ctx->session->start_consumer) {
2339 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2340 ret = start_consumerd(&kconsumer_data);
2341 if (ret < 0) {
2342 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
2343 goto error;
2344 }
2345 uatomic_set(&kernel_consumerd_state, CONSUMER_STARTED);
2346 } else {
2347 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2348 }
2349
2350 /*
2351 * The consumer was just spawned so we need to add the socket to
2352 * the consumer output of the session if exist.
2353 */
2354 ret = consumer_create_socket(&kconsumer_data,
2355 cmd_ctx->session->kernel_session->consumer);
2356 if (ret < 0) {
2357 goto error;
2358 }
2359 }
2360
2361 break;
2362 case LTTNG_DOMAIN_UST:
2363 {
2364 /* Consumer is in an ERROR state. Report back to client */
2365 if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
2366 ret = LTTNG_ERR_NO_USTCONSUMERD;
2367 goto error;
2368 }
2369
2370 if (need_tracing_session) {
2371 /* Create UST session if none exist. */
2372 if (cmd_ctx->session->ust_session == NULL) {
2373 ret = create_ust_session(cmd_ctx->session,
2374 &cmd_ctx->lsm->domain);
2375 if (ret != LTTNG_OK) {
2376 goto error;
2377 }
2378 }
2379
2380 /* Start the UST consumer daemons */
2381 /* 64-bit */
2382 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
2383 if (consumerd64_bin[0] != '\0' &&
2384 ustconsumer64_data.pid == 0 &&
2385 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER &&
2386 cmd_ctx->session->start_consumer) {
2387 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
2388 ret = start_consumerd(&ustconsumer64_data);
2389 if (ret < 0) {
2390 ret = LTTNG_ERR_UST_CONSUMER64_FAIL;
2391 uatomic_set(&ust_consumerd64_fd, -EINVAL);
2392 goto error;
2393 }
2394
2395 uatomic_set(&ust_consumerd64_fd, ustconsumer64_data.cmd_sock);
2396 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
2397 } else {
2398 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
2399 }
2400
2401 /*
2402 * Setup socket for consumer 64 bit. No need for atomic access
2403 * since it was set above and can ONLY be set in this thread.
2404 */
2405 ret = consumer_create_socket(&ustconsumer64_data,
2406 cmd_ctx->session->ust_session->consumer);
2407 if (ret < 0) {
2408 goto error;
2409 }
2410
2411 /* 32-bit */
2412 if (consumerd32_bin[0] != '\0' &&
2413 ustconsumer32_data.pid == 0 &&
2414 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER &&
2415 cmd_ctx->session->start_consumer) {
2416 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
2417 ret = start_consumerd(&ustconsumer32_data);
2418 if (ret < 0) {
2419 ret = LTTNG_ERR_UST_CONSUMER32_FAIL;
2420 uatomic_set(&ust_consumerd32_fd, -EINVAL);
2421 goto error;
2422 }
2423
2424 uatomic_set(&ust_consumerd32_fd, ustconsumer32_data.cmd_sock);
2425 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
2426 } else {
2427 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
2428 }
2429
2430 /*
2431 * Setup socket for consumer 64 bit. No need for atomic access
2432 * since it was set above and can ONLY be set in this thread.
2433 */
2434 ret = consumer_create_socket(&ustconsumer32_data,
2435 cmd_ctx->session->ust_session->consumer);
2436 if (ret < 0) {
2437 goto error;
2438 }
2439 }
2440 break;
2441 }
2442 default:
2443 break;
2444 }
2445 skip_domain:
2446
2447 /* Validate consumer daemon state when start/stop trace command */
2448 if (cmd_ctx->lsm->cmd_type == LTTNG_START_TRACE ||
2449 cmd_ctx->lsm->cmd_type == LTTNG_STOP_TRACE) {
2450 switch (cmd_ctx->lsm->domain.type) {
2451 case LTTNG_DOMAIN_UST:
2452 if (uatomic_read(&ust_consumerd_state) != CONSUMER_STARTED) {
2453 ret = LTTNG_ERR_NO_USTCONSUMERD;
2454 goto error;
2455 }
2456 break;
2457 case LTTNG_DOMAIN_KERNEL:
2458 if (uatomic_read(&kernel_consumerd_state) != CONSUMER_STARTED) {
2459 ret = LTTNG_ERR_NO_KERNCONSUMERD;
2460 goto error;
2461 }
2462 break;
2463 }
2464 }
2465
2466 /*
2467 * Check that the UID or GID match that of the tracing session.
2468 * The root user can interact with all sessions.
2469 */
2470 if (need_tracing_session) {
2471 if (!session_access_ok(cmd_ctx->session,
2472 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
2473 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds))) {
2474 ret = LTTNG_ERR_EPERM;
2475 goto error;
2476 }
2477 }
2478
2479 /* Process by command type */
2480 switch (cmd_ctx->lsm->cmd_type) {
2481 case LTTNG_ADD_CONTEXT:
2482 {
2483 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2484 cmd_ctx->lsm->u.context.channel_name,
2485 &cmd_ctx->lsm->u.context.ctx, kernel_poll_pipe[1]);
2486 break;
2487 }
2488 case LTTNG_DISABLE_CHANNEL:
2489 {
2490 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2491 cmd_ctx->lsm->u.disable.channel_name);
2492 break;
2493 }
2494 case LTTNG_DISABLE_EVENT:
2495 {
2496 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2497 cmd_ctx->lsm->u.disable.channel_name,
2498 cmd_ctx->lsm->u.disable.name);
2499 break;
2500 }
2501 case LTTNG_DISABLE_ALL_EVENT:
2502 {
2503 DBG("Disabling all events");
2504
2505 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2506 cmd_ctx->lsm->u.disable.channel_name);
2507 break;
2508 }
2509 case LTTNG_DISABLE_CONSUMER:
2510 {
2511 ret = cmd_disable_consumer(cmd_ctx->lsm->domain.type, cmd_ctx->session);
2512 break;
2513 }
2514 case LTTNG_ENABLE_CHANNEL:
2515 {
2516 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2517 &cmd_ctx->lsm->u.channel.chan, kernel_poll_pipe[1]);
2518 break;
2519 }
2520 case LTTNG_ENABLE_CONSUMER:
2521 {
2522 /*
2523 * XXX: 0 means that this URI should be applied on the session. Should
2524 * be a DOMAIN enuam.
2525 */
2526 ret = cmd_enable_consumer(cmd_ctx->lsm->domain.type, cmd_ctx->session);
2527 if (ret != LTTNG_OK) {
2528 goto error;
2529 }
2530
2531 if (cmd_ctx->lsm->domain.type == 0) {
2532 /* Add the URI for the UST session if a consumer is present. */
2533 if (cmd_ctx->session->ust_session &&
2534 cmd_ctx->session->ust_session->consumer) {
2535 ret = cmd_enable_consumer(LTTNG_DOMAIN_UST, cmd_ctx->session);
2536 } else if (cmd_ctx->session->kernel_session &&
2537 cmd_ctx->session->kernel_session->consumer) {
2538 ret = cmd_enable_consumer(LTTNG_DOMAIN_KERNEL,
2539 cmd_ctx->session);
2540 }
2541 }
2542 break;
2543 }
2544 case LTTNG_ENABLE_EVENT:
2545 {
2546 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2547 cmd_ctx->lsm->u.enable.channel_name,
2548 &cmd_ctx->lsm->u.enable.event, NULL, kernel_poll_pipe[1]);
2549 break;
2550 }
2551 case LTTNG_ENABLE_ALL_EVENT:
2552 {
2553 DBG("Enabling all events");
2554
2555 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2556 cmd_ctx->lsm->u.enable.channel_name,
2557 cmd_ctx->lsm->u.enable.event.type, NULL, kernel_poll_pipe[1]);
2558 break;
2559 }
2560 case LTTNG_LIST_TRACEPOINTS:
2561 {
2562 struct lttng_event *events;
2563 ssize_t nb_events;
2564
2565 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
2566 if (nb_events < 0) {
2567 /* Return value is a negative lttng_error_code. */
2568 ret = -nb_events;
2569 goto error;
2570 }
2571
2572 /*
2573 * Setup lttng message with payload size set to the event list size in
2574 * bytes and then copy list into the llm payload.
2575 */
2576 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
2577 if (ret < 0) {
2578 free(events);
2579 goto setup_error;
2580 }
2581
2582 /* Copy event list into message payload */
2583 memcpy(cmd_ctx->llm->payload, events,
2584 sizeof(struct lttng_event) * nb_events);
2585
2586 free(events);
2587
2588 ret = LTTNG_OK;
2589 break;
2590 }
2591 case LTTNG_LIST_TRACEPOINT_FIELDS:
2592 {
2593 struct lttng_event_field *fields;
2594 ssize_t nb_fields;
2595
2596 nb_fields = cmd_list_tracepoint_fields(cmd_ctx->lsm->domain.type,
2597 &fields);
2598 if (nb_fields < 0) {
2599 /* Return value is a negative lttng_error_code. */
2600 ret = -nb_fields;
2601 goto error;
2602 }
2603
2604 /*
2605 * Setup lttng message with payload size set to the event list size in
2606 * bytes and then copy list into the llm payload.
2607 */
2608 ret = setup_lttng_msg(cmd_ctx,
2609 sizeof(struct lttng_event_field) * nb_fields);
2610 if (ret < 0) {
2611 free(fields);
2612 goto setup_error;
2613 }
2614
2615 /* Copy event list into message payload */
2616 memcpy(cmd_ctx->llm->payload, fields,
2617 sizeof(struct lttng_event_field) * nb_fields);
2618
2619 free(fields);
2620
2621 ret = LTTNG_OK;
2622 break;
2623 }
2624 case LTTNG_SET_CONSUMER_URI:
2625 {
2626 size_t nb_uri, len;
2627 struct lttng_uri *uris;
2628
2629 nb_uri = cmd_ctx->lsm->u.uri.size;
2630 len = nb_uri * sizeof(struct lttng_uri);
2631
2632 if (nb_uri == 0) {
2633 ret = LTTNG_ERR_INVALID;
2634 goto error;
2635 }
2636
2637 uris = zmalloc(len);
2638 if (uris == NULL) {
2639 ret = LTTNG_ERR_FATAL;
2640 goto error;
2641 }
2642
2643 /* Receive variable len data */
2644 DBG("Receiving %zu URI(s) from client ...", nb_uri);
2645 ret = lttcomm_recv_unix_sock(sock, uris, len);
2646 if (ret <= 0) {
2647 DBG("No URIs received from client... continuing");
2648 *sock_error = 1;
2649 ret = LTTNG_ERR_SESSION_FAIL;
2650 free(uris);
2651 goto error;
2652 }
2653
2654 ret = cmd_set_consumer_uri(cmd_ctx->lsm->domain.type, cmd_ctx->session,
2655 nb_uri, uris);
2656 if (ret != LTTNG_OK) {
2657 free(uris);
2658 goto error;
2659 }
2660
2661 /*
2662 * XXX: 0 means that this URI should be applied on the session. Should
2663 * be a DOMAIN enuam.
2664 */
2665 if (cmd_ctx->lsm->domain.type == 0) {
2666 /* Add the URI for the UST session if a consumer is present. */
2667 if (cmd_ctx->session->ust_session &&
2668 cmd_ctx->session->ust_session->consumer) {
2669 ret = cmd_set_consumer_uri(LTTNG_DOMAIN_UST, cmd_ctx->session,
2670 nb_uri, uris);
2671 } else if (cmd_ctx->session->kernel_session &&
2672 cmd_ctx->session->kernel_session->consumer) {
2673 ret = cmd_set_consumer_uri(LTTNG_DOMAIN_KERNEL,
2674 cmd_ctx->session, nb_uri, uris);
2675 }
2676 }
2677
2678 free(uris);
2679
2680 break;
2681 }
2682 case LTTNG_START_TRACE:
2683 {
2684 ret = cmd_start_trace(cmd_ctx->session);
2685 break;
2686 }
2687 case LTTNG_STOP_TRACE:
2688 {
2689 ret = cmd_stop_trace(cmd_ctx->session);
2690 break;
2691 }
2692 case LTTNG_CREATE_SESSION:
2693 {
2694 size_t nb_uri, len;
2695 struct lttng_uri *uris = NULL;
2696
2697 nb_uri = cmd_ctx->lsm->u.uri.size;
2698 len = nb_uri * sizeof(struct lttng_uri);
2699
2700 if (nb_uri > 0) {
2701 uris = zmalloc(len);
2702 if (uris == NULL) {
2703 ret = LTTNG_ERR_FATAL;
2704 goto error;
2705 }
2706
2707 /* Receive variable len data */
2708 DBG("Waiting for %zu URIs from client ...", nb_uri);
2709 ret = lttcomm_recv_unix_sock(sock, uris, len);
2710 if (ret <= 0) {
2711 DBG("No URIs received from client... continuing");
2712 *sock_error = 1;
2713 ret = LTTNG_ERR_SESSION_FAIL;
2714 free(uris);
2715 goto error;
2716 }
2717
2718 if (nb_uri == 1 && uris[0].dtype != LTTNG_DST_PATH) {
2719 DBG("Creating session with ONE network URI is a bad call");
2720 ret = LTTNG_ERR_SESSION_FAIL;
2721 free(uris);
2722 goto error;
2723 }
2724 }
2725
2726 ret = cmd_create_session_uri(cmd_ctx->lsm->session.name, uris, nb_uri,
2727 &cmd_ctx->creds);
2728
2729 free(uris);
2730
2731 break;
2732 }
2733 case LTTNG_DESTROY_SESSION:
2734 {
2735 ret = cmd_destroy_session(cmd_ctx->session, kernel_poll_pipe[1]);
2736
2737 /* Set session to NULL so we do not unlock it after free. */
2738 cmd_ctx->session = NULL;
2739 break;
2740 }
2741 case LTTNG_LIST_DOMAINS:
2742 {
2743 ssize_t nb_dom;
2744 struct lttng_domain *domains;
2745
2746 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
2747 if (nb_dom < 0) {
2748 /* Return value is a negative lttng_error_code. */
2749 ret = -nb_dom;
2750 goto error;
2751 }
2752
2753 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
2754 if (ret < 0) {
2755 goto setup_error;
2756 }
2757
2758 /* Copy event list into message payload */
2759 memcpy(cmd_ctx->llm->payload, domains,
2760 nb_dom * sizeof(struct lttng_domain));
2761
2762 free(domains);
2763
2764 ret = LTTNG_OK;
2765 break;
2766 }
2767 case LTTNG_LIST_CHANNELS:
2768 {
2769 int nb_chan;
2770 struct lttng_channel *channels;
2771
2772 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
2773 cmd_ctx->session, &channels);
2774 if (nb_chan < 0) {
2775 /* Return value is a negative lttng_error_code. */
2776 ret = -nb_chan;
2777 goto error;
2778 }
2779
2780 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
2781 if (ret < 0) {
2782 goto setup_error;
2783 }
2784
2785 /* Copy event list into message payload */
2786 memcpy(cmd_ctx->llm->payload, channels,
2787 nb_chan * sizeof(struct lttng_channel));
2788
2789 free(channels);
2790
2791 ret = LTTNG_OK;
2792 break;
2793 }
2794 case LTTNG_LIST_EVENTS:
2795 {
2796 ssize_t nb_event;
2797 struct lttng_event *events = NULL;
2798
2799 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
2800 cmd_ctx->lsm->u.list.channel_name, &events);
2801 if (nb_event < 0) {
2802 /* Return value is a negative lttng_error_code. */
2803 ret = -nb_event;
2804 goto error;
2805 }
2806
2807 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
2808 if (ret < 0) {
2809 goto setup_error;
2810 }
2811
2812 /* Copy event list into message payload */
2813 memcpy(cmd_ctx->llm->payload, events,
2814 nb_event * sizeof(struct lttng_event));
2815
2816 free(events);
2817
2818 ret = LTTNG_OK;
2819 break;
2820 }
2821 case LTTNG_LIST_SESSIONS:
2822 {
2823 unsigned int nr_sessions;
2824
2825 session_lock_list();
2826 nr_sessions = lttng_sessions_count(
2827 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
2828 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
2829
2830 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * nr_sessions);
2831 if (ret < 0) {
2832 session_unlock_list();
2833 goto setup_error;
2834 }
2835
2836 /* Filled the session array */
2837 cmd_list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload),
2838 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
2839 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
2840
2841 session_unlock_list();
2842
2843 ret = LTTNG_OK;
2844 break;
2845 }
2846 case LTTNG_CALIBRATE:
2847 {
2848 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
2849 &cmd_ctx->lsm->u.calibrate);
2850 break;
2851 }
2852 case LTTNG_REGISTER_CONSUMER:
2853 {
2854 struct consumer_data *cdata;
2855
2856 switch (cmd_ctx->lsm->domain.type) {
2857 case LTTNG_DOMAIN_KERNEL:
2858 cdata = &kconsumer_data;
2859 break;
2860 default:
2861 ret = LTTNG_ERR_UND;
2862 goto error;
2863 }
2864
2865 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2866 cmd_ctx->lsm->u.reg.path, cdata);
2867 break;
2868 }
2869 case LTTNG_ENABLE_EVENT_WITH_FILTER:
2870 {
2871 struct lttng_filter_bytecode *bytecode;
2872
2873 if (cmd_ctx->lsm->u.enable.bytecode_len > LTTNG_FILTER_MAX_LEN) {
2874 ret = LTTNG_ERR_FILTER_INVAL;
2875 goto error;
2876 }
2877 if (cmd_ctx->lsm->u.enable.bytecode_len == 0) {
2878 ret = LTTNG_ERR_FILTER_INVAL;
2879 goto error;
2880 }
2881 bytecode = zmalloc(cmd_ctx->lsm->u.enable.bytecode_len);
2882 if (!bytecode) {
2883 ret = LTTNG_ERR_FILTER_NOMEM;
2884 goto error;
2885 }
2886 /* Receive var. len. data */
2887 DBG("Receiving var len data from client ...");
2888 ret = lttcomm_recv_unix_sock(sock, bytecode,
2889 cmd_ctx->lsm->u.enable.bytecode_len);
2890 if (ret <= 0) {
2891 DBG("Nothing recv() from client var len data... continuing");
2892 *sock_error = 1;
2893 ret = LTTNG_ERR_FILTER_INVAL;
2894 goto error;
2895 }
2896
2897 if (bytecode->len + sizeof(*bytecode)
2898 != cmd_ctx->lsm->u.enable.bytecode_len) {
2899 free(bytecode);
2900 ret = LTTNG_ERR_FILTER_INVAL;
2901 goto error;
2902 }
2903
2904 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
2905 cmd_ctx->lsm->u.enable.channel_name,
2906 &cmd_ctx->lsm->u.enable.event, bytecode, kernel_poll_pipe[1]);
2907 break;
2908 }
2909 case LTTNG_DATA_PENDING:
2910 {
2911 ret = cmd_data_pending(cmd_ctx->session);
2912 break;
2913 }
2914 default:
2915 ret = LTTNG_ERR_UND;
2916 break;
2917 }
2918
2919 error:
2920 if (cmd_ctx->llm == NULL) {
2921 DBG("Missing llm structure. Allocating one.");
2922 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
2923 goto setup_error;
2924 }
2925 }
2926 /* Set return code */
2927 cmd_ctx->llm->ret_code = ret;
2928 setup_error:
2929 if (cmd_ctx->session) {
2930 session_unlock(cmd_ctx->session);
2931 }
2932 if (need_tracing_session) {
2933 session_unlock_list();
2934 }
2935 init_setup_error:
2936 return ret;
2937 }
2938
2939 /*
2940 * Thread managing health check socket.
2941 */
2942 static void *thread_manage_health(void *data)
2943 {
2944 int sock = -1, new_sock = -1, ret, i, pollfd, err = -1;
2945 uint32_t revents, nb_fd;
2946 struct lttng_poll_event events;
2947 struct lttcomm_health_msg msg;
2948 struct lttcomm_health_data reply;
2949
2950 DBG("[thread] Manage health check started");
2951
2952 rcu_register_thread();
2953
2954 /* Create unix socket */
2955 sock = lttcomm_create_unix_sock(health_unix_sock_path);
2956 if (sock < 0) {
2957 ERR("Unable to create health check Unix socket");
2958 ret = -1;
2959 goto error;
2960 }
2961
2962 /*
2963 * Set the CLOEXEC flag. Return code is useless because either way, the
2964 * show must go on.
2965 */
2966 (void) utils_set_fd_cloexec(sock);
2967
2968 ret = lttcomm_listen_unix_sock(sock);
2969 if (ret < 0) {
2970 goto error;
2971 }
2972
2973 /*
2974 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2975 * more will be added to this poll set.
2976 */
2977 ret = create_thread_poll_set(&events, 2);
2978 if (ret < 0) {
2979 goto error;
2980 }
2981
2982 /* Add the application registration socket */
2983 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLPRI);
2984 if (ret < 0) {
2985 goto error;
2986 }
2987
2988 while (1) {
2989 DBG("Health check ready");
2990
2991 /* Inifinite blocking call, waiting for transmission */
2992 restart:
2993 ret = lttng_poll_wait(&events, -1);
2994 if (ret < 0) {
2995 /*
2996 * Restart interrupted system call.
2997 */
2998 if (errno == EINTR) {
2999 goto restart;
3000 }
3001 goto error;
3002 }
3003
3004 nb_fd = ret;
3005
3006 for (i = 0; i < nb_fd; i++) {
3007 /* Fetch once the poll data */
3008 revents = LTTNG_POLL_GETEV(&events, i);
3009 pollfd = LTTNG_POLL_GETFD(&events, i);
3010
3011 /* Thread quit pipe has been closed. Killing thread. */
3012 ret = check_thread_quit_pipe(pollfd, revents);
3013 if (ret) {
3014 err = 0;
3015 goto exit;
3016 }
3017
3018 /* Event on the registration socket */
3019 if (pollfd == sock) {
3020 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3021 ERR("Health socket poll error");
3022 goto error;
3023 }
3024 }
3025 }
3026
3027 new_sock = lttcomm_accept_unix_sock(sock);
3028 if (new_sock < 0) {
3029 goto error;
3030 }
3031
3032 /*
3033 * Set the CLOEXEC flag. Return code is useless because either way, the
3034 * show must go on.
3035 */
3036 (void) utils_set_fd_cloexec(new_sock);
3037
3038 DBG("Receiving data from client for health...");
3039 ret = lttcomm_recv_unix_sock(new_sock, (void *)&msg, sizeof(msg));
3040 if (ret <= 0) {
3041 DBG("Nothing recv() from client... continuing");
3042 ret = close(new_sock);
3043 if (ret) {
3044 PERROR("close");
3045 }
3046 new_sock = -1;
3047 continue;
3048 }
3049
3050 rcu_thread_online();
3051
3052 switch (msg.component) {
3053 case LTTNG_HEALTH_CMD:
3054 reply.ret_code = health_check_state(HEALTH_TYPE_CMD);
3055 break;
3056 case LTTNG_HEALTH_APP_MANAGE:
3057 reply.ret_code = health_check_state(HEALTH_TYPE_APP_MANAGE);
3058 break;
3059 case LTTNG_HEALTH_APP_REG:
3060 reply.ret_code = health_check_state(HEALTH_TYPE_APP_REG);
3061 break;
3062 case LTTNG_HEALTH_KERNEL:
3063 reply.ret_code = health_check_state(HEALTH_TYPE_KERNEL);
3064 break;
3065 case LTTNG_HEALTH_CONSUMER:
3066 reply.ret_code = check_consumer_health();
3067 break;
3068 case LTTNG_HEALTH_ALL:
3069 reply.ret_code =
3070 health_check_state(HEALTH_TYPE_APP_MANAGE) &&
3071 health_check_state(HEALTH_TYPE_APP_REG) &&
3072 health_check_state(HEALTH_TYPE_CMD) &&
3073 health_check_state(HEALTH_TYPE_KERNEL) &&
3074 check_consumer_health();
3075 break;
3076 default:
3077 reply.ret_code = LTTNG_ERR_UND;
3078 break;
3079 }
3080
3081 /*
3082 * Flip ret value since 0 is a success and 1 indicates a bad health for
3083 * the client where in the sessiond it is the opposite. Again, this is
3084 * just to make things easier for us poor developer which enjoy a lot
3085 * lazyness.
3086 */
3087 if (reply.ret_code == 0 || reply.ret_code == 1) {
3088 reply.ret_code = !reply.ret_code;
3089 }
3090
3091 DBG2("Health check return value %d", reply.ret_code);
3092
3093 ret = send_unix_sock(new_sock, (void *) &reply, sizeof(reply));
3094 if (ret < 0) {
3095 ERR("Failed to send health data back to client");
3096 }
3097
3098 /* End of transmission */
3099 ret = close(new_sock);
3100 if (ret) {
3101 PERROR("close");
3102 }
3103 new_sock = -1;
3104 }
3105
3106 exit:
3107 error:
3108 if (err) {
3109 ERR("Health error occurred in %s", __func__);
3110 }
3111 DBG("Health check thread dying");
3112 unlink(health_unix_sock_path);
3113 if (sock >= 0) {
3114 ret = close(sock);
3115 if (ret) {
3116 PERROR("close");
3117 }
3118 }
3119 if (new_sock >= 0) {
3120 ret = close(new_sock);
3121 if (ret) {
3122 PERROR("close");
3123 }
3124 }
3125
3126 lttng_poll_clean(&events);
3127
3128 rcu_unregister_thread();
3129 return NULL;
3130 }
3131
3132 /*
3133 * This thread manage all clients request using the unix client socket for
3134 * communication.
3135 */
3136 static void *thread_manage_clients(void *data)
3137 {
3138 int sock = -1, ret, i, pollfd, err = -1;
3139 int sock_error;
3140 uint32_t revents, nb_fd;
3141 struct command_ctx *cmd_ctx = NULL;
3142 struct lttng_poll_event events;
3143
3144 DBG("[thread] Manage client started");
3145
3146 rcu_register_thread();
3147
3148 health_register(HEALTH_TYPE_CMD);
3149
3150 if (testpoint(thread_manage_clients)) {
3151 goto error_testpoint;
3152 }
3153
3154 health_code_update();
3155
3156 ret = lttcomm_listen_unix_sock(client_sock);
3157 if (ret < 0) {
3158 goto error_listen;
3159 }
3160
3161 /*
3162 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3163 * more will be added to this poll set.
3164 */
3165 ret = create_thread_poll_set(&events, 2);
3166 if (ret < 0) {
3167 goto error_create_poll;
3168 }
3169
3170 /* Add the application registration socket */
3171 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3172 if (ret < 0) {
3173 goto error;
3174 }
3175
3176 /*
3177 * Notify parent pid that we are ready to accept command for client side.
3178 */
3179 if (opt_sig_parent) {
3180 kill(ppid, SIGUSR1);
3181 }
3182
3183 if (testpoint(thread_manage_clients_before_loop)) {
3184 goto error;
3185 }
3186
3187 health_code_update();
3188
3189 while (1) {
3190 DBG("Accepting client command ...");
3191
3192 /* Inifinite blocking call, waiting for transmission */
3193 restart:
3194 health_poll_entry();
3195 ret = lttng_poll_wait(&events, -1);
3196 health_poll_exit();
3197 if (ret < 0) {
3198 /*
3199 * Restart interrupted system call.
3200 */
3201 if (errno == EINTR) {
3202 goto restart;
3203 }
3204 goto error;
3205 }
3206
3207 nb_fd = ret;
3208
3209 for (i = 0; i < nb_fd; i++) {
3210 /* Fetch once the poll data */
3211 revents = LTTNG_POLL_GETEV(&events, i);
3212 pollfd = LTTNG_POLL_GETFD(&events, i);
3213
3214 health_code_update();
3215
3216 /* Thread quit pipe has been closed. Killing thread. */
3217 ret = check_thread_quit_pipe(pollfd, revents);
3218 if (ret) {
3219 err = 0;
3220 goto exit;
3221 }
3222
3223 /* Event on the registration socket */
3224 if (pollfd == client_sock) {
3225 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3226 ERR("Client socket poll error");
3227 goto error;
3228 }
3229 }
3230 }
3231
3232 DBG("Wait for client response");
3233
3234 health_code_update();
3235
3236 sock = lttcomm_accept_unix_sock(client_sock);
3237 if (sock < 0) {
3238 goto error;
3239 }
3240
3241 /*
3242 * Set the CLOEXEC flag. Return code is useless because either way, the
3243 * show must go on.
3244 */
3245 (void) utils_set_fd_cloexec(sock);
3246
3247 /* Set socket option for credentials retrieval */
3248 ret = lttcomm_setsockopt_creds_unix_sock(sock);
3249 if (ret < 0) {
3250 goto error;
3251 }
3252
3253 /* Allocate context command to process the client request */
3254 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3255 if (cmd_ctx == NULL) {
3256 PERROR("zmalloc cmd_ctx");
3257 goto error;
3258 }
3259
3260 /* Allocate data buffer for reception */
3261 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3262 if (cmd_ctx->lsm == NULL) {
3263 PERROR("zmalloc cmd_ctx->lsm");
3264 goto error;
3265 }
3266
3267 cmd_ctx->llm = NULL;
3268 cmd_ctx->session = NULL;
3269
3270 health_code_update();
3271
3272 /*
3273 * Data is received from the lttng client. The struct
3274 * lttcomm_session_msg (lsm) contains the command and data request of
3275 * the client.
3276 */
3277 DBG("Receiving data from client ...");
3278 ret = lttcomm_recv_creds_unix_sock(sock, cmd_ctx->lsm,
3279 sizeof(struct lttcomm_session_msg), &cmd_ctx->creds);
3280 if (ret <= 0) {
3281 DBG("Nothing recv() from client... continuing");
3282 ret = close(sock);
3283 if (ret) {
3284 PERROR("close");
3285 }
3286 sock = -1;
3287 clean_command_ctx(&cmd_ctx);
3288 continue;
3289 }
3290
3291 health_code_update();
3292
3293 // TODO: Validate cmd_ctx including sanity check for
3294 // security purpose.
3295
3296 rcu_thread_online();
3297 /*
3298 * This function dispatch the work to the kernel or userspace tracer
3299 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3300 * informations for the client. The command context struct contains
3301 * everything this function may needs.
3302 */
3303 ret = process_client_msg(cmd_ctx, sock, &sock_error);
3304 rcu_thread_offline();
3305 if (ret < 0) {
3306 if (sock_error) {
3307 ret = close(sock);
3308 if (ret) {
3309 PERROR("close");
3310 }
3311 sock = -1;
3312 }
3313 /*
3314 * TODO: Inform client somehow of the fatal error. At
3315 * this point, ret < 0 means that a zmalloc failed
3316 * (ENOMEM). Error detected but still accept
3317 * command, unless a socket error has been
3318 * detected.
3319 */
3320 clean_command_ctx(&cmd_ctx);
3321 continue;
3322 }
3323
3324 health_code_update();
3325
3326 DBG("Sending response (size: %d, retcode: %s)",
3327 cmd_ctx->lttng_msg_size,
3328 lttng_strerror(-cmd_ctx->llm->ret_code));
3329 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3330 if (ret < 0) {
3331 ERR("Failed to send data back to client");
3332 }
3333
3334 /* End of transmission */
3335 ret = close(sock);
3336 if (ret) {
3337 PERROR("close");
3338 }
3339 sock = -1;
3340
3341 clean_command_ctx(&cmd_ctx);
3342
3343 health_code_update();
3344 }
3345
3346 exit:
3347 error:
3348 if (sock >= 0) {
3349 ret = close(sock);
3350 if (ret) {
3351 PERROR("close");
3352 }
3353 }
3354
3355 lttng_poll_clean(&events);
3356 clean_command_ctx(&cmd_ctx);
3357
3358 error_listen:
3359 error_create_poll:
3360 error_testpoint:
3361 unlink(client_unix_sock_path);
3362 if (client_sock >= 0) {
3363 ret = close(client_sock);
3364 if (ret) {
3365 PERROR("close");
3366 }
3367 }
3368
3369 if (err) {
3370 health_error();
3371 ERR("Health error occurred in %s", __func__);
3372 }
3373
3374 health_unregister();
3375
3376 DBG("Client thread dying");
3377
3378 rcu_unregister_thread();
3379 return NULL;
3380 }
3381
3382
3383 /*
3384 * usage function on stderr
3385 */
3386 static void usage(void)
3387 {
3388 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3389 fprintf(stderr, " -h, --help Display this usage.\n");
3390 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3391 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3392 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3393 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3394 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
3395 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
3396 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
3397 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
3398 fprintf(stderr, " --consumerd32-path PATH Specify path for the 32-bit UST consumer daemon binary\n");
3399 fprintf(stderr, " --consumerd32-libdir PATH Specify path for the 32-bit UST consumer daemon libraries\n");
3400 fprintf(stderr, " --consumerd64-path PATH Specify path for the 64-bit UST consumer daemon binary\n");
3401 fprintf(stderr, " --consumerd64-libdir PATH Specify path for the 64-bit UST consumer daemon libraries\n");
3402 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3403 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3404 fprintf(stderr, " -V, --version Show version number.\n");
3405 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3406 fprintf(stderr, " -q, --quiet No output at all.\n");
3407 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3408 fprintf(stderr, " -p, --pidfile FILE Write a pid to FILE name overriding the default value.\n");
3409 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3410 fprintf(stderr, " --no-kernel Disable kernel tracer\n");
3411 }
3412
3413 /*
3414 * daemon argument parsing
3415 */
3416 static int parse_args(int argc, char **argv)
3417 {
3418 int c;
3419
3420 static struct option long_options[] = {
3421 { "client-sock", 1, 0, 'c' },
3422 { "apps-sock", 1, 0, 'a' },
3423 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3424 { "kconsumerd-err-sock", 1, 0, 'E' },
3425 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
3426 { "ustconsumerd32-err-sock", 1, 0, 'H' },
3427 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
3428 { "ustconsumerd64-err-sock", 1, 0, 'F' },
3429 { "consumerd32-path", 1, 0, 'u' },
3430 { "consumerd32-libdir", 1, 0, 'U' },
3431 { "consumerd64-path", 1, 0, 't' },
3432 { "consumerd64-libdir", 1, 0, 'T' },
3433 { "daemonize", 0, 0, 'd' },
3434 { "sig-parent", 0, 0, 'S' },
3435 { "help", 0, 0, 'h' },
3436 { "group", 1, 0, 'g' },
3437 { "version", 0, 0, 'V' },
3438 { "quiet", 0, 0, 'q' },
3439 { "verbose", 0, 0, 'v' },
3440 { "verbose-consumer", 0, 0, 'Z' },
3441 { "no-kernel", 0, 0, 'N' },
3442 { "pidfile", 1, 0, 'p' },
3443 { NULL, 0, 0, 0 }
3444 };
3445
3446 while (1) {
3447 int option_index = 0;
3448 c = getopt_long(argc, argv, "dhqvVSN" "a:c:g:s:C:E:D:F:Z:u:t:p:",
3449 long_options, &option_index);
3450 if (c == -1) {
3451 break;
3452 }
3453
3454 switch (c) {
3455 case 0:
3456 fprintf(stderr, "option %s", long_options[option_index].name);
3457 if (optarg) {
3458 fprintf(stderr, " with arg %s\n", optarg);
3459 }
3460 break;
3461 case 'c':
3462 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3463 break;
3464 case 'a':
3465 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3466 break;
3467 case 'd':
3468 opt_daemon = 1;
3469 break;
3470 case 'g':
3471 opt_tracing_group = optarg;
3472 break;
3473 case 'h':
3474 usage();
3475 exit(EXIT_FAILURE);
3476 case 'V':
3477 fprintf(stdout, "%s\n", VERSION);
3478 exit(EXIT_SUCCESS);
3479 case 'S':
3480 opt_sig_parent = 1;
3481 break;
3482 case 'E':
3483 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3484 break;
3485 case 'C':
3486 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3487 break;
3488 case 'F':
3489 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3490 break;
3491 case 'D':
3492 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3493 break;
3494 case 'H':
3495 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3496 break;
3497 case 'G':
3498 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3499 break;
3500 case 'N':
3501 opt_no_kernel = 1;
3502 break;
3503 case 'q':
3504 lttng_opt_quiet = 1;
3505 break;
3506 case 'v':
3507 /* Verbose level can increase using multiple -v */
3508 lttng_opt_verbose += 1;
3509 break;
3510 case 'Z':
3511 opt_verbose_consumer += 1;
3512 break;
3513 case 'u':
3514 consumerd32_bin= optarg;
3515 break;
3516 case 'U':
3517 consumerd32_libdir = optarg;
3518 break;
3519 case 't':
3520 consumerd64_bin = optarg;
3521 break;
3522 case 'T':
3523 consumerd64_libdir = optarg;
3524 break;
3525 case 'p':
3526 opt_pidfile = optarg;
3527 break;
3528 default:
3529 /* Unknown option or other error.
3530 * Error is printed by getopt, just return */
3531 return -1;
3532 }
3533 }
3534
3535 return 0;
3536 }
3537
3538 /*
3539 * Creates the two needed socket by the daemon.
3540 * apps_sock - The communication socket for all UST apps.
3541 * client_sock - The communication of the cli tool (lttng).
3542 */
3543 static int init_daemon_socket(void)
3544 {
3545 int ret = 0;
3546 mode_t old_umask;
3547
3548 old_umask = umask(0);
3549
3550 /* Create client tool unix socket */
3551 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3552 if (client_sock < 0) {
3553 ERR("Create unix sock failed: %s", client_unix_sock_path);
3554 ret = -1;
3555 goto end;
3556 }
3557
3558 /* Set the cloexec flag */
3559 ret = utils_set_fd_cloexec(client_sock);
3560 if (ret < 0) {
3561 ERR("Unable to set CLOEXEC flag to the client Unix socket (fd: %d). "
3562 "Continuing but note that the consumer daemon will have a "
3563 "reference to this socket on exec()", client_sock);
3564 }
3565
3566 /* File permission MUST be 660 */
3567 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3568 if (ret < 0) {
3569 ERR("Set file permissions failed: %s", client_unix_sock_path);
3570 PERROR("chmod");
3571 goto end;
3572 }
3573
3574 /* Create the application unix socket */
3575 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3576 if (apps_sock < 0) {
3577 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3578 ret = -1;
3579 goto end;
3580 }
3581
3582 /* Set the cloexec flag */
3583 ret = utils_set_fd_cloexec(apps_sock);
3584 if (ret < 0) {
3585 ERR("Unable to set CLOEXEC flag to the app Unix socket (fd: %d). "
3586 "Continuing but note that the consumer daemon will have a "
3587 "reference to this socket on exec()", apps_sock);
3588 }
3589
3590 /* File permission MUST be 666 */
3591 ret = chmod(apps_unix_sock_path,
3592 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3593 if (ret < 0) {
3594 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3595 PERROR("chmod");
3596 goto end;
3597 }
3598
3599 DBG3("Session daemon client socket %d and application socket %d created",
3600 client_sock, apps_sock);
3601
3602 end:
3603 umask(old_umask);
3604 return ret;
3605 }
3606
3607 /*
3608 * Check if the global socket is available, and if a daemon is answering at the
3609 * other side. If yes, error is returned.
3610 */
3611 static int check_existing_daemon(void)
3612 {
3613 /* Is there anybody out there ? */
3614 if (lttng_session_daemon_alive()) {
3615 return -EEXIST;
3616 }
3617
3618 return 0;
3619 }
3620
3621 /*
3622 * Set the tracing group gid onto the client socket.
3623 *
3624 * Race window between mkdir and chown is OK because we are going from more
3625 * permissive (root.root) to less permissive (root.tracing).
3626 */
3627 static int set_permissions(char *rundir)
3628 {
3629 int ret;
3630 gid_t gid;
3631
3632 ret = allowed_group();
3633 if (ret < 0) {
3634 WARN("No tracing group detected");
3635 ret = 0;
3636 goto end;
3637 }
3638
3639 gid = ret;
3640
3641 /* Set lttng run dir */
3642 ret = chown(rundir, 0, gid);
3643 if (ret < 0) {
3644 ERR("Unable to set group on %s", rundir);
3645 PERROR("chown");
3646 }
3647
3648 /* Ensure tracing group can search the run dir */
3649 ret = chmod(rundir, S_IRWXU | S_IXGRP | S_IXOTH);
3650 if (ret < 0) {
3651 ERR("Unable to set permissions on %s", rundir);
3652 PERROR("chmod");
3653 }
3654
3655 /* lttng client socket path */
3656 ret = chown(client_unix_sock_path, 0, gid);
3657 if (ret < 0) {
3658 ERR("Unable to set group on %s", client_unix_sock_path);
3659 PERROR("chown");
3660 }
3661
3662 /* kconsumer error socket path */
3663 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
3664 if (ret < 0) {
3665 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
3666 PERROR("chown");
3667 }
3668
3669 /* 64-bit ustconsumer error socket path */
3670 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
3671 if (ret < 0) {
3672 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
3673 PERROR("chown");
3674 }
3675
3676 /* 32-bit ustconsumer compat32 error socket path */
3677 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
3678 if (ret < 0) {
3679 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
3680 PERROR("chown");
3681 }
3682
3683 DBG("All permissions are set");
3684
3685 end:
3686 return ret;
3687 }
3688
3689 /*
3690 * Create the lttng run directory needed for all global sockets and pipe.
3691 */
3692 static int create_lttng_rundir(const char *rundir)
3693 {
3694 int ret;
3695
3696 DBG3("Creating LTTng run directory: %s", rundir);
3697
3698 ret = mkdir(rundir, S_IRWXU);
3699 if (ret < 0) {
3700 if (errno != EEXIST) {
3701 ERR("Unable to create %s", rundir);
3702 goto error;
3703 } else {
3704 ret = 0;
3705 }
3706 }
3707
3708 error:
3709 return ret;
3710 }
3711
3712 /*
3713 * Setup sockets and directory needed by the kconsumerd communication with the
3714 * session daemon.
3715 */
3716 static int set_consumer_sockets(struct consumer_data *consumer_data,
3717 const char *rundir)
3718 {
3719 int ret;
3720 char path[PATH_MAX];
3721
3722 switch (consumer_data->type) {
3723 case LTTNG_CONSUMER_KERNEL:
3724 snprintf(path, PATH_MAX, DEFAULT_KCONSUMERD_PATH, rundir);
3725 break;
3726 case LTTNG_CONSUMER64_UST:
3727 snprintf(path, PATH_MAX, DEFAULT_USTCONSUMERD64_PATH, rundir);
3728 break;
3729 case LTTNG_CONSUMER32_UST:
3730 snprintf(path, PATH_MAX, DEFAULT_USTCONSUMERD32_PATH, rundir);
3731 break;
3732 default:
3733 ERR("Consumer type unknown");
3734 ret = -EINVAL;
3735 goto error;
3736 }
3737
3738 DBG2("Creating consumer directory: %s", path);
3739
3740 ret = mkdir(path, S_IRWXU);
3741 if (ret < 0) {
3742 if (errno != EEXIST) {
3743 PERROR("mkdir");
3744 ERR("Failed to create %s", path);
3745 goto error;
3746 }
3747 ret = -1;
3748 }
3749
3750 /* Create the kconsumerd error unix socket */
3751 consumer_data->err_sock =
3752 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
3753 if (consumer_data->err_sock < 0) {
3754 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
3755 ret = -1;
3756 goto error;
3757 }
3758
3759 /* File permission MUST be 660 */
3760 ret = chmod(consumer_data->err_unix_sock_path,
3761 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3762 if (ret < 0) {
3763 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
3764 PERROR("chmod");
3765 goto error;
3766 }
3767
3768 error:
3769 return ret;
3770 }
3771
3772 /*
3773 * Signal handler for the daemon
3774 *
3775 * Simply stop all worker threads, leaving main() return gracefully after
3776 * joining all threads and calling cleanup().
3777 */
3778 static void sighandler(int sig)
3779 {
3780 switch (sig) {
3781 case SIGPIPE:
3782 DBG("SIGPIPE caught");
3783 return;
3784 case SIGINT:
3785 DBG("SIGINT caught");
3786 stop_threads();
3787 break;
3788 case SIGTERM:
3789 DBG("SIGTERM caught");
3790 stop_threads();
3791 break;
3792 default:
3793 break;
3794 }
3795 }
3796
3797 /*
3798 * Setup signal handler for :
3799 * SIGINT, SIGTERM, SIGPIPE
3800 */
3801 static int set_signal_handler(void)
3802 {
3803 int ret = 0;
3804 struct sigaction sa;
3805 sigset_t sigset;
3806
3807 if ((ret = sigemptyset(&sigset)) < 0) {
3808 PERROR("sigemptyset");
3809 return ret;
3810 }
3811
3812 sa.sa_handler = sighandler;
3813 sa.sa_mask = sigset;
3814 sa.sa_flags = 0;
3815 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
3816 PERROR("sigaction");
3817 return ret;
3818 }
3819
3820 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
3821 PERROR("sigaction");
3822 return ret;
3823 }
3824
3825 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
3826 PERROR("sigaction");
3827 return ret;
3828 }
3829
3830 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3831
3832 return ret;
3833 }
3834
3835 /*
3836 * Set open files limit to unlimited. This daemon can open a large number of
3837 * file descriptors in order to consumer multiple kernel traces.
3838 */
3839 static void set_ulimit(void)
3840 {
3841 int ret;
3842 struct rlimit lim;
3843
3844 /* The kernel does not allowed an infinite limit for open files */
3845 lim.rlim_cur = 65535;
3846 lim.rlim_max = 65535;
3847
3848 ret = setrlimit(RLIMIT_NOFILE, &lim);
3849 if (ret < 0) {
3850 PERROR("failed to set open files limit");
3851 }
3852 }
3853
3854 /*
3855 * Write pidfile using the rundir and opt_pidfile.
3856 */
3857 static void write_pidfile(void)
3858 {
3859 int ret;
3860 char pidfile_path[PATH_MAX];
3861
3862 assert(rundir);
3863
3864 if (opt_pidfile) {
3865 strncpy(pidfile_path, opt_pidfile, sizeof(pidfile_path));
3866 } else {
3867 /* Build pidfile path from rundir and opt_pidfile. */
3868 ret = snprintf(pidfile_path, sizeof(pidfile_path), "%s/"
3869 DEFAULT_LTTNG_SESSIOND_PIDFILE, rundir);
3870 if (ret < 0) {
3871 PERROR("snprintf pidfile path");
3872 goto error;
3873 }
3874 }
3875
3876 /*
3877 * Create pid file in rundir. Return value is of no importance. The
3878 * execution will continue even though we are not able to write the file.
3879 */
3880 (void) utils_create_pid_file(getpid(), pidfile_path);
3881
3882 error:
3883 return;
3884 }
3885
3886 /*
3887 * main
3888 */
3889 int main(int argc, char **argv)
3890 {
3891 int ret = 0;
3892 void *status;
3893 const char *home_path, *env_app_timeout;
3894
3895 init_kernel_workarounds();
3896
3897 rcu_register_thread();
3898
3899 setup_consumerd_path();
3900
3901 /* Parse arguments */
3902 progname = argv[0];
3903 if ((ret = parse_args(argc, argv)) < 0) {
3904 goto error;
3905 }
3906
3907 /* Daemonize */
3908 if (opt_daemon) {
3909 int i;
3910
3911 /*
3912 * fork
3913 * child: setsid, close FD 0, 1, 2, chdir /
3914 * parent: exit (if fork is successful)
3915 */
3916 ret = daemon(0, 0);
3917 if (ret < 0) {
3918 PERROR("daemon");
3919 goto error;
3920 }
3921 /*
3922 * We are in the child. Make sure all other file
3923 * descriptors are closed, in case we are called with
3924 * more opened file descriptors than the standard ones.
3925 */
3926 for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
3927 (void) close(i);
3928 }
3929 }
3930
3931 /* Create thread quit pipe */
3932 if ((ret = init_thread_quit_pipe()) < 0) {
3933 goto error;
3934 }
3935
3936 /* Check if daemon is UID = 0 */
3937 is_root = !getuid();
3938
3939 if (is_root) {
3940 rundir = strdup(DEFAULT_LTTNG_RUNDIR);
3941
3942 /* Create global run dir with root access */
3943 ret = create_lttng_rundir(rundir);
3944 if (ret < 0) {
3945 goto error;
3946 }
3947
3948 if (strlen(apps_unix_sock_path) == 0) {
3949 snprintf(apps_unix_sock_path, PATH_MAX,
3950 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
3951 }
3952
3953 if (strlen(client_unix_sock_path) == 0) {
3954 snprintf(client_unix_sock_path, PATH_MAX,
3955 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
3956 }
3957
3958 /* Set global SHM for ust */
3959 if (strlen(wait_shm_path) == 0) {
3960 snprintf(wait_shm_path, PATH_MAX,
3961 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
3962 }
3963
3964 if (strlen(health_unix_sock_path) == 0) {
3965 snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
3966 DEFAULT_GLOBAL_HEALTH_UNIX_SOCK);
3967 }
3968
3969 /* Setup kernel consumerd path */
3970 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX,
3971 DEFAULT_KCONSUMERD_ERR_SOCK_PATH, rundir);
3972 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX,
3973 DEFAULT_KCONSUMERD_CMD_SOCK_PATH, rundir);
3974
3975 DBG2("Kernel consumer err path: %s",
3976 kconsumer_data.err_unix_sock_path);
3977 DBG2("Kernel consumer cmd path: %s",
3978 kconsumer_data.cmd_unix_sock_path);
3979 } else {
3980 home_path = get_home_dir();
3981 if (home_path == NULL) {
3982 /* TODO: Add --socket PATH option */
3983 ERR("Can't get HOME directory for sockets creation.");
3984 ret = -EPERM;
3985 goto error;
3986 }
3987
3988 /*
3989 * Create rundir from home path. This will create something like
3990 * $HOME/.lttng
3991 */
3992 ret = asprintf(&rundir, DEFAULT_LTTNG_HOME_RUNDIR, home_path);
3993 if (ret < 0) {
3994 ret = -ENOMEM;
3995 goto error;
3996 }
3997
3998 ret = create_lttng_rundir(rundir);
3999 if (ret < 0) {
4000 goto error;
4001 }
4002
4003 if (strlen(apps_unix_sock_path) == 0) {
4004 snprintf(apps_unix_sock_path, PATH_MAX,
4005 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
4006 }
4007
4008 /* Set the cli tool unix socket path */
4009 if (strlen(client_unix_sock_path) == 0) {
4010 snprintf(client_unix_sock_path, PATH_MAX,
4011 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
4012 }
4013
4014 /* Set global SHM for ust */
4015 if (strlen(wait_shm_path) == 0) {
4016 snprintf(wait_shm_path, PATH_MAX,
4017 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
4018 }
4019
4020 /* Set health check Unix path */
4021 if (strlen(health_unix_sock_path) == 0) {
4022 snprintf(health_unix_sock_path, sizeof(health_unix_sock_path),
4023 DEFAULT_HOME_HEALTH_UNIX_SOCK, home_path);
4024 }
4025 }
4026
4027 /* Set consumer initial state */
4028 kernel_consumerd_state = CONSUMER_STOPPED;
4029 ust_consumerd_state = CONSUMER_STOPPED;
4030
4031 DBG("Client socket path %s", client_unix_sock_path);
4032 DBG("Application socket path %s", apps_unix_sock_path);
4033 DBG("LTTng run directory path: %s", rundir);
4034
4035 /* 32 bits consumerd path setup */
4036 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX,
4037 DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH, rundir);
4038 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX,
4039 DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH, rundir);
4040
4041 DBG2("UST consumer 32 bits err path: %s",
4042 ustconsumer32_data.err_unix_sock_path);
4043 DBG2("UST consumer 32 bits cmd path: %s",
4044 ustconsumer32_data.cmd_unix_sock_path);
4045
4046 /* 64 bits consumerd path setup */
4047 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX,
4048 DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH, rundir);
4049 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX,
4050 DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH, rundir);
4051
4052 DBG2("UST consumer 64 bits err path: %s",
4053 ustconsumer64_data.err_unix_sock_path);
4054 DBG2("UST consumer 64 bits cmd path: %s",
4055 ustconsumer64_data.cmd_unix_sock_path);
4056
4057 /*
4058 * See if daemon already exist.
4059 */
4060 if ((ret = check_existing_daemon()) < 0) {
4061 ERR("Already running daemon.\n");
4062 /*
4063 * We do not goto exit because we must not cleanup()
4064 * because a daemon is already running.
4065 */
4066 goto error;
4067 }
4068
4069 /*
4070 * Init UST app hash table. Alloc hash table before this point since
4071 * cleanup() can get called after that point.
4072 */
4073 ust_app_ht_alloc();
4074
4075 /* After this point, we can safely call cleanup() with "goto exit" */
4076
4077 /*
4078 * These actions must be executed as root. We do that *after* setting up
4079 * the sockets path because we MUST make the check for another daemon using
4080 * those paths *before* trying to set the kernel consumer sockets and init
4081 * kernel tracer.
4082 */
4083 if (is_root) {
4084 ret = set_consumer_sockets(&kconsumer_data, rundir);
4085 if (ret < 0) {
4086 goto exit;
4087 }
4088
4089 /* Setup kernel tracer */
4090 if (!opt_no_kernel) {
4091 init_kernel_tracer();
4092 }
4093
4094 /* Set ulimit for open files */
4095 set_ulimit();
4096 }
4097 /* init lttng_fd tracking must be done after set_ulimit. */
4098 lttng_fd_init();
4099
4100 ret = set_consumer_sockets(&ustconsumer64_data, rundir);
4101 if (ret < 0) {
4102 goto exit;
4103 }
4104
4105 ret = set_consumer_sockets(&ustconsumer32_data, rundir);
4106 if (ret < 0) {
4107 goto exit;
4108 }
4109
4110 if ((ret = set_signal_handler()) < 0) {
4111 goto exit;
4112 }
4113
4114 /* Setup the needed unix socket */
4115 if ((ret = init_daemon_socket()) < 0) {
4116 goto exit;
4117 }
4118
4119 /* Set credentials to socket */
4120 if (is_root && ((ret = set_permissions(rundir)) < 0)) {
4121 goto exit;
4122 }
4123
4124 /* Get parent pid if -S, --sig-parent is specified. */
4125 if (opt_sig_parent) {
4126 ppid = getppid();
4127 }
4128
4129 /* Setup the kernel pipe for waking up the kernel thread */
4130 if (is_root && !opt_no_kernel) {
4131 if ((ret = utils_create_pipe_cloexec(kernel_poll_pipe)) < 0) {
4132 goto exit;
4133 }
4134 }
4135
4136 /* Setup the thread apps communication pipe. */
4137 if ((ret = utils_create_pipe_cloexec(apps_cmd_pipe)) < 0) {
4138 goto exit;
4139 }
4140
4141 /* Init UST command queue. */
4142 cds_wfq_init(&ust_cmd_queue.queue);
4143
4144 /*
4145 * Get session list pointer. This pointer MUST NOT be free(). This list is
4146 * statically declared in session.c
4147 */
4148 session_list_ptr = session_get_list();
4149
4150 /* Set up max poll set size */
4151 lttng_poll_set_max_size();
4152
4153 cmd_init();
4154
4155 /* Check for the application socket timeout env variable. */
4156 env_app_timeout = getenv(DEFAULT_APP_SOCKET_TIMEOUT_ENV);
4157 if (env_app_timeout) {
4158 app_socket_timeout = atoi(env_app_timeout);
4159 } else {
4160 app_socket_timeout = DEFAULT_APP_SOCKET_RW_TIMEOUT;
4161 }
4162
4163 write_pidfile();
4164
4165 /* Create thread to manage the client socket */
4166 ret = pthread_create(&health_thread, NULL,
4167 thread_manage_health, (void *) NULL);
4168 if (ret != 0) {
4169 PERROR("pthread_create health");
4170 goto exit_health;
4171 }
4172
4173 /* Create thread to manage the client socket */
4174 ret = pthread_create(&client_thread, NULL,
4175 thread_manage_clients, (void *) NULL);
4176 if (ret != 0) {
4177 PERROR("pthread_create clients");
4178 goto exit_client;
4179 }
4180
4181 /* Create thread to dispatch registration */
4182 ret = pthread_create(&dispatch_thread, NULL,
4183 thread_dispatch_ust_registration, (void *) NULL);
4184 if (ret != 0) {
4185 PERROR("pthread_create dispatch");
4186 goto exit_dispatch;
4187 }
4188
4189 /* Create thread to manage application registration. */
4190 ret = pthread_create(&reg_apps_thread, NULL,
4191 thread_registration_apps, (void *) NULL);
4192 if (ret != 0) {
4193 PERROR("pthread_create registration");
4194 goto exit_reg_apps;
4195 }
4196
4197 /* Create thread to manage application socket */
4198 ret = pthread_create(&apps_thread, NULL,
4199 thread_manage_apps, (void *) NULL);
4200 if (ret != 0) {
4201 PERROR("pthread_create apps");
4202 goto exit_apps;
4203 }
4204
4205 /* Don't start this thread if kernel tracing is not requested nor root */
4206 if (is_root && !opt_no_kernel) {
4207 /* Create kernel thread to manage kernel event */
4208 ret = pthread_create(&kernel_thread, NULL,
4209 thread_manage_kernel, (void *) NULL);
4210 if (ret != 0) {
4211 PERROR("pthread_create kernel");
4212 goto exit_kernel;
4213 }
4214
4215 ret = pthread_join(kernel_thread, &status);
4216 if (ret != 0) {
4217 PERROR("pthread_join");
4218 goto error; /* join error, exit without cleanup */
4219 }
4220 }
4221
4222 exit_kernel:
4223 ret = pthread_join(apps_thread, &status);
4224 if (ret != 0) {
4225 PERROR("pthread_join");
4226 goto error; /* join error, exit without cleanup */
4227 }
4228
4229 exit_apps:
4230 ret = pthread_join(reg_apps_thread, &status);
4231 if (ret != 0) {
4232 PERROR("pthread_join");
4233 goto error; /* join error, exit without cleanup */
4234 }
4235
4236 exit_reg_apps:
4237 ret = pthread_join(dispatch_thread, &status);
4238 if (ret != 0) {
4239 PERROR("pthread_join");
4240 goto error; /* join error, exit without cleanup */
4241 }
4242
4243 exit_dispatch:
4244 ret = pthread_join(client_thread, &status);
4245 if (ret != 0) {
4246 PERROR("pthread_join");
4247 goto error; /* join error, exit without cleanup */
4248 }
4249
4250 ret = join_consumer_thread(&kconsumer_data);
4251 if (ret != 0) {
4252 PERROR("join_consumer");
4253 goto error; /* join error, exit without cleanup */
4254 }
4255
4256 ret = join_consumer_thread(&ustconsumer32_data);
4257 if (ret != 0) {
4258 PERROR("join_consumer ust32");
4259 goto error; /* join error, exit without cleanup */
4260 }
4261
4262 ret = join_consumer_thread(&ustconsumer64_data);
4263 if (ret != 0) {
4264 PERROR("join_consumer ust64");
4265 goto error; /* join error, exit without cleanup */
4266 }
4267
4268 exit_client:
4269 ret = pthread_join(health_thread, &status);
4270 if (ret != 0) {
4271 PERROR("pthread_join health thread");
4272 goto error; /* join error, exit without cleanup */
4273 }
4274
4275 exit_health:
4276 exit:
4277 /*
4278 * cleanup() is called when no other thread is running.
4279 */
4280 rcu_thread_online();
4281 cleanup();
4282 rcu_thread_offline();
4283 rcu_unregister_thread();
4284 if (!ret) {
4285 exit(EXIT_SUCCESS);
4286 }
4287 error:
4288 exit(EXIT_FAILURE);
4289 }
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