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8b512f01d8dcda417c41c0c11dcb3aaca7ca1d5f
[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 it
6 * under the terms of the GNU General Public License as published by the Free
7 * Software Foundation; only version 2 of the License.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
16 * Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18
19 #define _GNU_SOURCE
20 #include <fcntl.h>
21 #include <getopt.h>
22 #include <grp.h>
23 #include <limits.h>
24 #include <pthread.h>
25 #include <semaphore.h>
26 #include <signal.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <sys/mman.h>
31 #include <sys/mount.h>
32 #include <sys/resource.h>
33 #include <sys/socket.h>
34 #include <sys/stat.h>
35 #include <sys/types.h>
36 #include <sys/wait.h>
37 #include <urcu/futex.h>
38 #include <unistd.h>
39 #include <config.h>
40
41 #include <bin/lttng-consumerd/lttng-consumerd.h>
42 #include <common/lttngerr.h>
43 #include <common/kernel-consumer/kernel-consumer.h>
44 #include <common/ust-consumer/ust-consumer.h>
45 #include <common/common.h>
46 #include <common/defaults.h>
47 #include <common/compat/poll.h>
48
49 #include "lttng-sessiond.h"
50 #include "channel.h"
51 #include "context.h"
52 #include "event.h"
53 #include "futex.h"
54 #include "kernel.h"
55 #include "shm.h"
56 #include "ust-ctl.h"
57 #include "utils.h"
58
59 #define CONSUMERD_FILE "lttng-consumerd"
60
61 struct consumer_data {
62 enum lttng_consumer_type type;
63
64 pthread_t thread; /* Worker thread interacting with the consumer */
65 sem_t sem;
66
67 /* Mutex to control consumerd pid assignation */
68 pthread_mutex_t pid_mutex;
69 pid_t pid;
70
71 int err_sock;
72 int cmd_sock;
73
74 /* consumer error and command Unix socket path */
75 char err_unix_sock_path[PATH_MAX];
76 char cmd_unix_sock_path[PATH_MAX];
77 };
78
79 /* Const values */
80 const char default_home_dir[] = DEFAULT_HOME_DIR;
81 const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
82 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
83 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
84
85 /* Variables */
86 int opt_verbose; /* Not static for lttngerr.h */
87 int opt_verbose_consumer; /* Not static for lttngerr.h */
88 int opt_quiet; /* Not static for lttngerr.h */
89
90 const char *progname;
91 const char *opt_tracing_group;
92 static int opt_sig_parent;
93 static int opt_daemon;
94 static int opt_no_kernel;
95 static int is_root; /* Set to 1 if the daemon is running as root */
96 static pid_t ppid; /* Parent PID for --sig-parent option */
97 static char *rundir;
98
99 /* Consumer daemon specific control data */
100 static struct consumer_data kconsumer_data = {
101 .type = LTTNG_CONSUMER_KERNEL,
102 .err_unix_sock_path = KCONSUMERD_ERR_SOCK_PATH,
103 .cmd_unix_sock_path = KCONSUMERD_CMD_SOCK_PATH,
104 };
105 static struct consumer_data ustconsumer64_data = {
106 .type = LTTNG_CONSUMER64_UST,
107 .err_unix_sock_path = USTCONSUMERD64_ERR_SOCK_PATH,
108 .cmd_unix_sock_path = USTCONSUMERD64_CMD_SOCK_PATH,
109 };
110 static struct consumer_data ustconsumer32_data = {
111 .type = LTTNG_CONSUMER32_UST,
112 .err_unix_sock_path = USTCONSUMERD32_ERR_SOCK_PATH,
113 .cmd_unix_sock_path = USTCONSUMERD32_CMD_SOCK_PATH,
114 };
115
116 static int dispatch_thread_exit;
117
118 /* Global application Unix socket path */
119 static char apps_unix_sock_path[PATH_MAX];
120 /* Global client Unix socket path */
121 static char client_unix_sock_path[PATH_MAX];
122 /* global wait shm path for UST */
123 static char wait_shm_path[PATH_MAX];
124
125 /* Sockets and FDs */
126 static int client_sock;
127 static int apps_sock;
128 static int kernel_tracer_fd;
129 static int kernel_poll_pipe[2];
130
131 /*
132 * Quit pipe for all threads. This permits a single cancellation point
133 * for all threads when receiving an event on the pipe.
134 */
135 static int thread_quit_pipe[2];
136
137 /*
138 * This pipe is used to inform the thread managing application communication
139 * that a command is queued and ready to be processed.
140 */
141 static int apps_cmd_pipe[2];
142
143 /* Pthread, Mutexes and Semaphores */
144 static pthread_t apps_thread;
145 static pthread_t reg_apps_thread;
146 static pthread_t client_thread;
147 static pthread_t kernel_thread;
148 static pthread_t dispatch_thread;
149
150
151 /*
152 * UST registration command queue. This queue is tied with a futex and uses a N
153 * wakers / 1 waiter implemented and detailed in futex.c/.h
154 *
155 * The thread_manage_apps and thread_dispatch_ust_registration interact with
156 * this queue and the wait/wake scheme.
157 */
158 static struct ust_cmd_queue ust_cmd_queue;
159
160 /*
161 * Pointer initialized before thread creation.
162 *
163 * This points to the tracing session list containing the session count and a
164 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
165 * MUST NOT be taken if you call a public function in session.c.
166 *
167 * The lock is nested inside the structure: session_list_ptr->lock. Please use
168 * session_lock_list and session_unlock_list for lock acquisition.
169 */
170 static struct ltt_session_list *session_list_ptr;
171
172 int ust_consumerd64_fd = -1;
173 int ust_consumerd32_fd = -1;
174
175 static const char *consumerd32_bin = CONFIG_CONSUMERD32_BIN;
176 static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
177 static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
178 static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
179
180 static
181 void setup_consumerd_path(void)
182 {
183 const char *bin, *libdir;
184
185 /*
186 * Allow INSTALL_BIN_PATH to be used as a target path for the
187 * native architecture size consumer if CONFIG_CONSUMER*_PATH
188 * has not been defined.
189 */
190 #if (CAA_BITS_PER_LONG == 32)
191 if (!consumerd32_bin[0]) {
192 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
193 }
194 if (!consumerd32_libdir[0]) {
195 consumerd32_libdir = INSTALL_LIB_PATH;
196 }
197 #elif (CAA_BITS_PER_LONG == 64)
198 if (!consumerd64_bin[0]) {
199 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
200 }
201 if (!consumerd64_libdir[0]) {
202 consumerd64_libdir = INSTALL_LIB_PATH;
203 }
204 #else
205 #error "Unknown bitness"
206 #endif
207
208 /*
209 * runtime env. var. overrides the build default.
210 */
211 bin = getenv("LTTNG_CONSUMERD32_BIN");
212 if (bin) {
213 consumerd32_bin = bin;
214 }
215 bin = getenv("LTTNG_CONSUMERD64_BIN");
216 if (bin) {
217 consumerd64_bin = bin;
218 }
219 libdir = getenv("LTTNG_TOOLS_CONSUMERD32_LIBDIR");
220 if (libdir) {
221 consumerd32_libdir = libdir;
222 }
223 libdir = getenv("LTTNG_TOOLS_CONSUMERD64_LIBDIR");
224 if (libdir) {
225 consumerd64_libdir = libdir;
226 }
227 }
228
229 /*
230 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
231 */
232 static int create_thread_poll_set(struct lttng_poll_event *events,
233 unsigned int size)
234 {
235 int ret;
236
237 if (events == NULL || size == 0) {
238 ret = -1;
239 goto error;
240 }
241
242 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
243 if (ret < 0) {
244 goto error;
245 }
246
247 /* Add quit pipe */
248 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
249 if (ret < 0) {
250 goto error;
251 }
252
253 return 0;
254
255 error:
256 return ret;
257 }
258
259 /*
260 * Check if the thread quit pipe was triggered.
261 *
262 * Return 1 if it was triggered else 0;
263 */
264 static int check_thread_quit_pipe(int fd, uint32_t events)
265 {
266 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
267 return 1;
268 }
269
270 return 0;
271 }
272
273 /*
274 * Remove modules in reverse load order.
275 */
276 static int modprobe_remove_kernel_modules(void)
277 {
278 int ret = 0, i;
279 char modprobe[256];
280
281 for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
282 ret = snprintf(modprobe, sizeof(modprobe),
283 "/sbin/modprobe -r -q %s",
284 kernel_modules_list[i].name);
285 if (ret < 0) {
286 perror("snprintf modprobe -r");
287 goto error;
288 }
289 modprobe[sizeof(modprobe) - 1] = '\0';
290 ret = system(modprobe);
291 if (ret == -1) {
292 ERR("Unable to launch modprobe -r for module %s",
293 kernel_modules_list[i].name);
294 } else if (kernel_modules_list[i].required
295 && WEXITSTATUS(ret) != 0) {
296 ERR("Unable to remove module %s",
297 kernel_modules_list[i].name);
298 } else {
299 DBG("Modprobe removal successful %s",
300 kernel_modules_list[i].name);
301 }
302 }
303
304 error:
305 return ret;
306 }
307
308 /*
309 * Return group ID of the tracing group or -1 if not found.
310 */
311 static gid_t allowed_group(void)
312 {
313 struct group *grp;
314
315 if (opt_tracing_group) {
316 grp = getgrnam(opt_tracing_group);
317 } else {
318 grp = getgrnam(default_tracing_group);
319 }
320 if (!grp) {
321 return -1;
322 } else {
323 return grp->gr_gid;
324 }
325 }
326
327 /*
328 * Init thread quit pipe.
329 *
330 * Return -1 on error or 0 if all pipes are created.
331 */
332 static int init_thread_quit_pipe(void)
333 {
334 int ret;
335
336 ret = pipe2(thread_quit_pipe, O_CLOEXEC);
337 if (ret < 0) {
338 perror("thread quit pipe");
339 goto error;
340 }
341
342 error:
343 return ret;
344 }
345
346 /*
347 * Complete teardown of a kernel session. This free all data structure related
348 * to a kernel session and update counter.
349 */
350 static void teardown_kernel_session(struct ltt_session *session)
351 {
352 if (!session->kernel_session) {
353 DBG3("No kernel session when tearingdown session");
354 return;
355 }
356
357 DBG("Tearing down kernel session");
358
359 /*
360 * If a custom kernel consumer was registered, close the socket before
361 * tearing down the complete kernel session structure
362 */
363 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
364 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
365 }
366
367 trace_kernel_destroy_session(session->kernel_session);
368 }
369
370 /*
371 * Complete teardown of all UST sessions. This will free everything on his path
372 * and destroy the core essence of all ust sessions :)
373 */
374 static void teardown_ust_session(struct ltt_session *session)
375 {
376 int ret;
377
378 if (!session->ust_session) {
379 DBG3("No UST session when tearingdown session");
380 return;
381 }
382
383 DBG("Tearing down UST session(s)");
384
385 ret = ust_app_destroy_trace_all(session->ust_session);
386 if (ret) {
387 ERR("Error in ust_app_destroy_trace_all");
388 }
389
390 trace_ust_destroy_session(session->ust_session);
391 }
392
393 /*
394 * Stop all threads by closing the thread quit pipe.
395 */
396 static void stop_threads(void)
397 {
398 int ret;
399
400 /* Stopping all threads */
401 DBG("Terminating all threads");
402 ret = notify_thread_pipe(thread_quit_pipe[1]);
403 if (ret < 0) {
404 ERR("write error on thread quit pipe");
405 }
406
407 /* Dispatch thread */
408 dispatch_thread_exit = 1;
409 futex_nto1_wake(&ust_cmd_queue.futex);
410 }
411
412 /*
413 * Cleanup the daemon
414 */
415 static void cleanup(void)
416 {
417 int ret;
418 char *cmd;
419 struct ltt_session *sess, *stmp;
420
421 DBG("Cleaning up");
422
423 DBG("Removing %s directory", rundir);
424 ret = asprintf(&cmd, "rm -rf %s", rundir);
425 if (ret < 0) {
426 ERR("asprintf failed. Something is really wrong!");
427 }
428
429 /* Remove lttng run directory */
430 ret = system(cmd);
431 if (ret < 0) {
432 ERR("Unable to clean %s", rundir);
433 }
434 free(cmd);
435
436 DBG("Cleaning up all session");
437
438 /* Destroy session list mutex */
439 if (session_list_ptr != NULL) {
440 pthread_mutex_destroy(&session_list_ptr->lock);
441
442 /* Cleanup ALL session */
443 cds_list_for_each_entry_safe(sess, stmp,
444 &session_list_ptr->head, list) {
445 teardown_kernel_session(sess);
446 teardown_ust_session(sess);
447 free(sess);
448 }
449 }
450
451 DBG("Closing all UST sockets");
452 ust_app_clean_list();
453
454 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
455
456 if (is_root && !opt_no_kernel) {
457 DBG2("Closing kernel fd");
458 close(kernel_tracer_fd);
459 DBG("Unloading kernel modules");
460 modprobe_remove_kernel_modules();
461 }
462
463 close(thread_quit_pipe[0]);
464 close(thread_quit_pipe[1]);
465
466 /* <fun> */
467 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
468 "Matthew, BEET driven development works!%c[%dm",
469 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
470 /* </fun> */
471 }
472
473 /*
474 * Send data on a unix socket using the liblttsessiondcomm API.
475 *
476 * Return lttcomm error code.
477 */
478 static int send_unix_sock(int sock, void *buf, size_t len)
479 {
480 /* Check valid length */
481 if (len <= 0) {
482 return -1;
483 }
484
485 return lttcomm_send_unix_sock(sock, buf, len);
486 }
487
488 /*
489 * Free memory of a command context structure.
490 */
491 static void clean_command_ctx(struct command_ctx **cmd_ctx)
492 {
493 DBG("Clean command context structure");
494 if (*cmd_ctx) {
495 if ((*cmd_ctx)->llm) {
496 free((*cmd_ctx)->llm);
497 }
498 if ((*cmd_ctx)->lsm) {
499 free((*cmd_ctx)->lsm);
500 }
501 free(*cmd_ctx);
502 *cmd_ctx = NULL;
503 }
504 }
505
506 /*
507 * Send all stream fds of kernel channel to the consumer.
508 */
509 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
510 int sock, struct ltt_kernel_channel *channel,
511 uid_t uid, gid_t gid)
512 {
513 int ret;
514 struct ltt_kernel_stream *stream;
515 struct lttcomm_consumer_msg lkm;
516
517 DBG("Sending streams of channel %s to kernel consumer",
518 channel->channel->name);
519
520 /* Send channel */
521 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
522 lkm.u.channel.channel_key = channel->fd;
523 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
524 lkm.u.channel.mmap_len = 0; /* for kernel */
525 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
526 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
527 if (ret < 0) {
528 perror("send consumer channel");
529 goto error;
530 }
531
532 /* Send streams */
533 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
534 if (!stream->fd) {
535 continue;
536 }
537 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
538 lkm.u.stream.channel_key = channel->fd;
539 lkm.u.stream.stream_key = stream->fd;
540 lkm.u.stream.state = stream->state;
541 lkm.u.stream.output = channel->channel->attr.output;
542 lkm.u.stream.mmap_len = 0; /* for kernel */
543 lkm.u.stream.uid = uid;
544 lkm.u.stream.gid = gid;
545 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
546 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
547 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
548 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
549 if (ret < 0) {
550 perror("send consumer stream");
551 goto error;
552 }
553 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
554 if (ret < 0) {
555 perror("send consumer stream ancillary data");
556 goto error;
557 }
558 }
559
560 DBG("consumer channel streams sent");
561
562 return 0;
563
564 error:
565 return ret;
566 }
567
568 /*
569 * Send all stream fds of the kernel session to the consumer.
570 */
571 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
572 struct ltt_kernel_session *session)
573 {
574 int ret;
575 struct ltt_kernel_channel *chan;
576 struct lttcomm_consumer_msg lkm;
577 int sock = session->consumer_fd;
578
579 DBG("Sending metadata stream fd");
580
581 /* Extra protection. It's NOT supposed to be set to 0 at this point */
582 if (session->consumer_fd == 0) {
583 session->consumer_fd = consumer_data->cmd_sock;
584 }
585
586 if (session->metadata_stream_fd != 0) {
587 /* Send metadata channel fd */
588 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
589 lkm.u.channel.channel_key = session->metadata->fd;
590 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
591 lkm.u.channel.mmap_len = 0; /* for kernel */
592 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
593 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
594 if (ret < 0) {
595 perror("send consumer channel");
596 goto error;
597 }
598
599 /* Send metadata stream fd */
600 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
601 lkm.u.stream.channel_key = session->metadata->fd;
602 lkm.u.stream.stream_key = session->metadata_stream_fd;
603 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
604 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
605 lkm.u.stream.mmap_len = 0; /* for kernel */
606 lkm.u.stream.uid = session->uid;
607 lkm.u.stream.gid = session->gid;
608 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
609 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
610 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
611 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
612 if (ret < 0) {
613 perror("send consumer stream");
614 goto error;
615 }
616 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
617 if (ret < 0) {
618 perror("send consumer stream");
619 goto error;
620 }
621 }
622
623 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
624 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
625 session->uid, session->gid);
626 if (ret < 0) {
627 goto error;
628 }
629 }
630
631 DBG("consumer fds (metadata and channel streams) sent");
632
633 return 0;
634
635 error:
636 return ret;
637 }
638
639 /*
640 * Notify UST applications using the shm mmap futex.
641 */
642 static int notify_ust_apps(int active)
643 {
644 char *wait_shm_mmap;
645
646 DBG("Notifying applications of session daemon state: %d", active);
647
648 /* See shm.c for this call implying mmap, shm and futex calls */
649 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
650 if (wait_shm_mmap == NULL) {
651 goto error;
652 }
653
654 /* Wake waiting process */
655 futex_wait_update((int32_t *) wait_shm_mmap, active);
656
657 /* Apps notified successfully */
658 return 0;
659
660 error:
661 return -1;
662 }
663
664 /*
665 * Setup the outgoing data buffer for the response (llm) by allocating the
666 * right amount of memory and copying the original information from the lsm
667 * structure.
668 *
669 * Return total size of the buffer pointed by buf.
670 */
671 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
672 {
673 int ret, buf_size;
674
675 buf_size = size;
676
677 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
678 if (cmd_ctx->llm == NULL) {
679 perror("zmalloc");
680 ret = -ENOMEM;
681 goto error;
682 }
683
684 /* Copy common data */
685 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
686 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
687
688 cmd_ctx->llm->data_size = size;
689 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
690
691 return buf_size;
692
693 error:
694 return ret;
695 }
696
697 /*
698 * Update the kernel poll set of all channel fd available over all tracing
699 * session. Add the wakeup pipe at the end of the set.
700 */
701 static int update_kernel_poll(struct lttng_poll_event *events)
702 {
703 int ret;
704 struct ltt_session *session;
705 struct ltt_kernel_channel *channel;
706
707 DBG("Updating kernel poll set");
708
709 session_lock_list();
710 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
711 session_lock(session);
712 if (session->kernel_session == NULL) {
713 session_unlock(session);
714 continue;
715 }
716
717 cds_list_for_each_entry(channel,
718 &session->kernel_session->channel_list.head, list) {
719 /* Add channel fd to the kernel poll set */
720 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
721 if (ret < 0) {
722 session_unlock(session);
723 goto error;
724 }
725 DBG("Channel fd %d added to kernel set", channel->fd);
726 }
727 session_unlock(session);
728 }
729 session_unlock_list();
730
731 return 0;
732
733 error:
734 session_unlock_list();
735 return -1;
736 }
737
738 /*
739 * Find the channel fd from 'fd' over all tracing session. When found, check
740 * for new channel stream and send those stream fds to the kernel consumer.
741 *
742 * Useful for CPU hotplug feature.
743 */
744 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
745 {
746 int ret = 0;
747 struct ltt_session *session;
748 struct ltt_kernel_channel *channel;
749
750 DBG("Updating kernel streams for channel fd %d", fd);
751
752 session_lock_list();
753 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
754 session_lock(session);
755 if (session->kernel_session == NULL) {
756 session_unlock(session);
757 continue;
758 }
759
760 /* This is not suppose to be 0 but this is an extra security check */
761 if (session->kernel_session->consumer_fd == 0) {
762 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
763 }
764
765 cds_list_for_each_entry(channel,
766 &session->kernel_session->channel_list.head, list) {
767 if (channel->fd == fd) {
768 DBG("Channel found, updating kernel streams");
769 ret = kernel_open_channel_stream(channel);
770 if (ret < 0) {
771 goto error;
772 }
773
774 /*
775 * Have we already sent fds to the consumer? If yes, it means
776 * that tracing is started so it is safe to send our updated
777 * stream fds.
778 */
779 if (session->kernel_session->consumer_fds_sent == 1) {
780 ret = send_kconsumer_channel_streams(consumer_data,
781 session->kernel_session->consumer_fd, channel,
782 session->uid, session->gid);
783 if (ret < 0) {
784 goto error;
785 }
786 }
787 goto error;
788 }
789 }
790 session_unlock(session);
791 }
792 session_unlock_list();
793 return ret;
794
795 error:
796 session_unlock(session);
797 session_unlock_list();
798 return ret;
799 }
800
801 /*
802 * For each tracing session, update newly registered apps.
803 */
804 static void update_ust_app(int app_sock)
805 {
806 struct ltt_session *sess, *stmp;
807
808 /* For all tracing session(s) */
809 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
810 if (sess->ust_session) {
811 ust_app_global_update(sess->ust_session, app_sock);
812 }
813 }
814 }
815
816 /*
817 * This thread manage event coming from the kernel.
818 *
819 * Features supported in this thread:
820 * -) CPU Hotplug
821 */
822 static void *thread_manage_kernel(void *data)
823 {
824 int ret, i, pollfd, update_poll_flag = 1;
825 uint32_t revents, nb_fd;
826 char tmp;
827 struct lttng_poll_event events;
828
829 DBG("Thread manage kernel started");
830
831 ret = create_thread_poll_set(&events, 2);
832 if (ret < 0) {
833 goto error;
834 }
835
836 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
837 if (ret < 0) {
838 goto error;
839 }
840
841 while (1) {
842 if (update_poll_flag == 1) {
843 /*
844 * Reset number of fd in the poll set. Always 2 since there is the thread
845 * quit pipe and the kernel pipe.
846 */
847 events.nb_fd = 2;
848
849 ret = update_kernel_poll(&events);
850 if (ret < 0) {
851 goto error;
852 }
853 update_poll_flag = 0;
854 }
855
856 nb_fd = LTTNG_POLL_GETNB(&events);
857
858 DBG("Thread kernel polling on %d fds", nb_fd);
859
860 /* Zeroed the poll events */
861 lttng_poll_reset(&events);
862
863 /* Poll infinite value of time */
864 ret = lttng_poll_wait(&events, -1);
865 if (ret < 0) {
866 goto error;
867 } else if (ret == 0) {
868 /* Should not happen since timeout is infinite */
869 ERR("Return value of poll is 0 with an infinite timeout.\n"
870 "This should not have happened! Continuing...");
871 continue;
872 }
873
874 for (i = 0; i < nb_fd; i++) {
875 /* Fetch once the poll data */
876 revents = LTTNG_POLL_GETEV(&events, i);
877 pollfd = LTTNG_POLL_GETFD(&events, i);
878
879 /* Thread quit pipe has been closed. Killing thread. */
880 ret = check_thread_quit_pipe(pollfd, revents);
881 if (ret) {
882 goto error;
883 }
884
885 /* Check for data on kernel pipe */
886 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
887 ret = read(kernel_poll_pipe[0], &tmp, 1);
888 update_poll_flag = 1;
889 continue;
890 } else {
891 /*
892 * New CPU detected by the kernel. Adding kernel stream to
893 * kernel session and updating the kernel consumer
894 */
895 if (revents & LPOLLIN) {
896 ret = update_kernel_stream(&kconsumer_data, pollfd);
897 if (ret < 0) {
898 continue;
899 }
900 break;
901 /*
902 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
903 * and unregister kernel stream at this point.
904 */
905 }
906 }
907 }
908 }
909
910 error:
911 DBG("Kernel thread dying");
912 close(kernel_poll_pipe[0]);
913 close(kernel_poll_pipe[1]);
914
915 lttng_poll_clean(&events);
916
917 return NULL;
918 }
919
920 /*
921 * This thread manage the consumer error sent back to the session daemon.
922 */
923 static void *thread_manage_consumer(void *data)
924 {
925 int sock = 0, i, ret, pollfd;
926 uint32_t revents, nb_fd;
927 enum lttcomm_return_code code;
928 struct lttng_poll_event events;
929 struct consumer_data *consumer_data = data;
930
931 DBG("[thread] Manage consumer started");
932
933 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
934 if (ret < 0) {
935 goto error;
936 }
937
938 /*
939 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
940 * Nothing more will be added to this poll set.
941 */
942 ret = create_thread_poll_set(&events, 2);
943 if (ret < 0) {
944 goto error;
945 }
946
947 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
948 if (ret < 0) {
949 goto error;
950 }
951
952 nb_fd = LTTNG_POLL_GETNB(&events);
953
954 /* Inifinite blocking call, waiting for transmission */
955 ret = lttng_poll_wait(&events, -1);
956 if (ret < 0) {
957 goto error;
958 }
959
960 for (i = 0; i < nb_fd; i++) {
961 /* Fetch once the poll data */
962 revents = LTTNG_POLL_GETEV(&events, i);
963 pollfd = LTTNG_POLL_GETFD(&events, i);
964
965 /* Thread quit pipe has been closed. Killing thread. */
966 ret = check_thread_quit_pipe(pollfd, revents);
967 if (ret) {
968 goto error;
969 }
970
971 /* Event on the registration socket */
972 if (pollfd == consumer_data->err_sock) {
973 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
974 ERR("consumer err socket poll error");
975 goto error;
976 }
977 }
978 }
979
980 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
981 if (sock < 0) {
982 goto error;
983 }
984
985 DBG2("Receiving code from consumer err_sock");
986
987 /* Getting status code from kconsumerd */
988 ret = lttcomm_recv_unix_sock(sock, &code,
989 sizeof(enum lttcomm_return_code));
990 if (ret <= 0) {
991 goto error;
992 }
993
994 if (code == CONSUMERD_COMMAND_SOCK_READY) {
995 consumer_data->cmd_sock =
996 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
997 if (consumer_data->cmd_sock < 0) {
998 sem_post(&consumer_data->sem);
999 PERROR("consumer connect");
1000 goto error;
1001 }
1002 /* Signal condition to tell that the kconsumerd is ready */
1003 sem_post(&consumer_data->sem);
1004 DBG("consumer command socket ready");
1005 } else {
1006 ERR("consumer error when waiting for SOCK_READY : %s",
1007 lttcomm_get_readable_code(-code));
1008 goto error;
1009 }
1010
1011 /* Remove the kconsumerd error sock since we've established a connexion */
1012 ret = lttng_poll_del(&events, consumer_data->err_sock);
1013 if (ret < 0) {
1014 goto error;
1015 }
1016
1017 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1018 if (ret < 0) {
1019 goto error;
1020 }
1021
1022 /* Update number of fd */
1023 nb_fd = LTTNG_POLL_GETNB(&events);
1024
1025 /* Inifinite blocking call, waiting for transmission */
1026 ret = lttng_poll_wait(&events, -1);
1027 if (ret < 0) {
1028 goto error;
1029 }
1030
1031 for (i = 0; i < nb_fd; i++) {
1032 /* Fetch once the poll data */
1033 revents = LTTNG_POLL_GETEV(&events, i);
1034 pollfd = LTTNG_POLL_GETFD(&events, i);
1035
1036 /* Thread quit pipe has been closed. Killing thread. */
1037 ret = check_thread_quit_pipe(pollfd, revents);
1038 if (ret) {
1039 goto error;
1040 }
1041
1042 /* Event on the kconsumerd socket */
1043 if (pollfd == sock) {
1044 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1045 ERR("consumer err socket second poll error");
1046 goto error;
1047 }
1048 }
1049 }
1050
1051 /* Wait for any kconsumerd error */
1052 ret = lttcomm_recv_unix_sock(sock, &code,
1053 sizeof(enum lttcomm_return_code));
1054 if (ret <= 0) {
1055 ERR("consumer closed the command socket");
1056 goto error;
1057 }
1058
1059 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1060
1061 error:
1062 DBG("consumer thread dying");
1063 close(consumer_data->err_sock);
1064 close(consumer_data->cmd_sock);
1065 close(sock);
1066
1067 unlink(consumer_data->err_unix_sock_path);
1068 unlink(consumer_data->cmd_unix_sock_path);
1069 consumer_data->pid = 0;
1070
1071 lttng_poll_clean(&events);
1072
1073 return NULL;
1074 }
1075
1076 /*
1077 * This thread manage application communication.
1078 */
1079 static void *thread_manage_apps(void *data)
1080 {
1081 int i, ret, pollfd;
1082 uint32_t revents, nb_fd;
1083 struct ust_command ust_cmd;
1084 struct lttng_poll_event events;
1085
1086 DBG("[thread] Manage application started");
1087
1088 rcu_register_thread();
1089 rcu_thread_online();
1090
1091 ret = create_thread_poll_set(&events, 2);
1092 if (ret < 0) {
1093 goto error;
1094 }
1095
1096 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1097 if (ret < 0) {
1098 goto error;
1099 }
1100
1101 while (1) {
1102 /* Zeroed the events structure */
1103 lttng_poll_reset(&events);
1104
1105 nb_fd = LTTNG_POLL_GETNB(&events);
1106
1107 DBG("Apps thread polling on %d fds", nb_fd);
1108
1109 /* Inifinite blocking call, waiting for transmission */
1110 ret = lttng_poll_wait(&events, -1);
1111 if (ret < 0) {
1112 goto error;
1113 }
1114
1115 for (i = 0; i < nb_fd; i++) {
1116 /* Fetch once the poll data */
1117 revents = LTTNG_POLL_GETEV(&events, i);
1118 pollfd = LTTNG_POLL_GETFD(&events, i);
1119
1120 /* Thread quit pipe has been closed. Killing thread. */
1121 ret = check_thread_quit_pipe(pollfd, revents);
1122 if (ret) {
1123 goto error;
1124 }
1125
1126 /* Inspect the apps cmd pipe */
1127 if (pollfd == apps_cmd_pipe[0]) {
1128 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1129 ERR("Apps command pipe error");
1130 goto error;
1131 } else if (revents & LPOLLIN) {
1132 /* Empty pipe */
1133 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1134 if (ret < 0 || ret < sizeof(ust_cmd)) {
1135 perror("read apps cmd pipe");
1136 goto error;
1137 }
1138
1139 /* Register applicaton to the session daemon */
1140 ret = ust_app_register(&ust_cmd.reg_msg,
1141 ust_cmd.sock);
1142 if (ret == -ENOMEM) {
1143 goto error;
1144 } else if (ret < 0) {
1145 break;
1146 }
1147
1148 /*
1149 * Add channel(s) and event(s) to newly registered apps
1150 * from lttng global UST domain.
1151 */
1152 update_ust_app(ust_cmd.sock);
1153
1154 ret = ust_app_register_done(ust_cmd.sock);
1155 if (ret < 0) {
1156 /*
1157 * If the registration is not possible, we simply
1158 * unregister the apps and continue
1159 */
1160 ust_app_unregister(ust_cmd.sock);
1161 } else {
1162 /*
1163 * We just need here to monitor the close of the UST
1164 * socket and poll set monitor those by default.
1165 */
1166 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1167 if (ret < 0) {
1168 goto error;
1169 }
1170
1171 DBG("Apps with sock %d added to poll set",
1172 ust_cmd.sock);
1173 }
1174
1175 break;
1176 }
1177 } else {
1178 /*
1179 * At this point, we know that a registered application made
1180 * the event at poll_wait.
1181 */
1182 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1183 /* Removing from the poll set */
1184 ret = lttng_poll_del(&events, pollfd);
1185 if (ret < 0) {
1186 goto error;
1187 }
1188
1189 /* Socket closed on remote end. */
1190 ust_app_unregister(pollfd);
1191 break;
1192 }
1193 }
1194 }
1195 }
1196
1197 error:
1198 DBG("Application communication apps dying");
1199 close(apps_cmd_pipe[0]);
1200 close(apps_cmd_pipe[1]);
1201
1202 lttng_poll_clean(&events);
1203
1204 rcu_thread_offline();
1205 rcu_unregister_thread();
1206 return NULL;
1207 }
1208
1209 /*
1210 * Dispatch request from the registration threads to the application
1211 * communication thread.
1212 */
1213 static void *thread_dispatch_ust_registration(void *data)
1214 {
1215 int ret;
1216 struct cds_wfq_node *node;
1217 struct ust_command *ust_cmd = NULL;
1218
1219 DBG("[thread] Dispatch UST command started");
1220
1221 while (!dispatch_thread_exit) {
1222 /* Atomically prepare the queue futex */
1223 futex_nto1_prepare(&ust_cmd_queue.futex);
1224
1225 do {
1226 /* Dequeue command for registration */
1227 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1228 if (node == NULL) {
1229 DBG("Woken up but nothing in the UST command queue");
1230 /* Continue thread execution */
1231 break;
1232 }
1233
1234 ust_cmd = caa_container_of(node, struct ust_command, node);
1235
1236 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1237 " gid:%d sock:%d name:%s (version %d.%d)",
1238 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1239 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1240 ust_cmd->sock, ust_cmd->reg_msg.name,
1241 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1242 /*
1243 * Inform apps thread of the new application registration. This
1244 * call is blocking so we can be assured that the data will be read
1245 * at some point in time or wait to the end of the world :)
1246 */
1247 ret = write(apps_cmd_pipe[1], ust_cmd,
1248 sizeof(struct ust_command));
1249 if (ret < 0) {
1250 perror("write apps cmd pipe");
1251 if (errno == EBADF) {
1252 /*
1253 * We can't inform the application thread to process
1254 * registration. We will exit or else application
1255 * registration will not occur and tracing will never
1256 * start.
1257 */
1258 goto error;
1259 }
1260 }
1261 free(ust_cmd);
1262 } while (node != NULL);
1263
1264 /* Futex wait on queue. Blocking call on futex() */
1265 futex_nto1_wait(&ust_cmd_queue.futex);
1266 }
1267
1268 error:
1269 DBG("Dispatch thread dying");
1270 return NULL;
1271 }
1272
1273 /*
1274 * This thread manage application registration.
1275 */
1276 static void *thread_registration_apps(void *data)
1277 {
1278 int sock = 0, i, ret, pollfd;
1279 uint32_t revents, nb_fd;
1280 struct lttng_poll_event events;
1281 /*
1282 * Get allocated in this thread, enqueued to a global queue, dequeued and
1283 * freed in the manage apps thread.
1284 */
1285 struct ust_command *ust_cmd = NULL;
1286
1287 DBG("[thread] Manage application registration started");
1288
1289 ret = lttcomm_listen_unix_sock(apps_sock);
1290 if (ret < 0) {
1291 goto error;
1292 }
1293
1294 /*
1295 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1296 * more will be added to this poll set.
1297 */
1298 ret = create_thread_poll_set(&events, 2);
1299 if (ret < 0) {
1300 goto error;
1301 }
1302
1303 /* Add the application registration socket */
1304 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1305 if (ret < 0) {
1306 goto error;
1307 }
1308
1309 /* Notify all applications to register */
1310 ret = notify_ust_apps(1);
1311 if (ret < 0) {
1312 ERR("Failed to notify applications or create the wait shared memory.\n"
1313 "Execution continues but there might be problem for already\n"
1314 "running applications that wishes to register.");
1315 }
1316
1317 while (1) {
1318 DBG("Accepting application registration");
1319
1320 nb_fd = LTTNG_POLL_GETNB(&events);
1321
1322 /* Inifinite blocking call, waiting for transmission */
1323 ret = lttng_poll_wait(&events, -1);
1324 if (ret < 0) {
1325 goto error;
1326 }
1327
1328 for (i = 0; i < nb_fd; i++) {
1329 /* Fetch once the poll data */
1330 revents = LTTNG_POLL_GETEV(&events, i);
1331 pollfd = LTTNG_POLL_GETFD(&events, i);
1332
1333 /* Thread quit pipe has been closed. Killing thread. */
1334 ret = check_thread_quit_pipe(pollfd, revents);
1335 if (ret) {
1336 goto error;
1337 }
1338
1339 /* Event on the registration socket */
1340 if (pollfd == apps_sock) {
1341 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1342 ERR("Register apps socket poll error");
1343 goto error;
1344 } else if (revents & LPOLLIN) {
1345 sock = lttcomm_accept_unix_sock(apps_sock);
1346 if (sock < 0) {
1347 goto error;
1348 }
1349
1350 /* Create UST registration command for enqueuing */
1351 ust_cmd = zmalloc(sizeof(struct ust_command));
1352 if (ust_cmd == NULL) {
1353 perror("ust command zmalloc");
1354 goto error;
1355 }
1356
1357 /*
1358 * Using message-based transmissions to ensure we don't
1359 * have to deal with partially received messages.
1360 */
1361 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1362 sizeof(struct ust_register_msg));
1363 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1364 if (ret < 0) {
1365 perror("lttcomm_recv_unix_sock register apps");
1366 } else {
1367 ERR("Wrong size received on apps register");
1368 }
1369 free(ust_cmd);
1370 close(sock);
1371 continue;
1372 }
1373
1374 ust_cmd->sock = sock;
1375
1376 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1377 " gid:%d sock:%d name:%s (version %d.%d)",
1378 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1379 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1380 ust_cmd->sock, ust_cmd->reg_msg.name,
1381 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1382
1383 /*
1384 * Lock free enqueue the registration request. The red pill
1385 * has been taken! This apps will be part of the *system*.
1386 */
1387 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1388
1389 /*
1390 * Wake the registration queue futex. Implicit memory
1391 * barrier with the exchange in cds_wfq_enqueue.
1392 */
1393 futex_nto1_wake(&ust_cmd_queue.futex);
1394 }
1395 }
1396 }
1397 }
1398
1399 error:
1400 DBG("UST Registration thread dying");
1401
1402 /* Notify that the registration thread is gone */
1403 notify_ust_apps(0);
1404
1405 close(apps_sock);
1406 close(sock);
1407 unlink(apps_unix_sock_path);
1408
1409 lttng_poll_clean(&events);
1410
1411 return NULL;
1412 }
1413
1414 /*
1415 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1416 * exec or it will fails.
1417 */
1418 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1419 {
1420 int ret;
1421 struct timespec timeout;
1422
1423 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1424 timeout.tv_nsec = 0;
1425
1426 /* Setup semaphore */
1427 ret = sem_init(&consumer_data->sem, 0, 0);
1428 if (ret < 0) {
1429 PERROR("sem_init consumer semaphore");
1430 goto error;
1431 }
1432
1433 ret = pthread_create(&consumer_data->thread, NULL,
1434 thread_manage_consumer, consumer_data);
1435 if (ret != 0) {
1436 PERROR("pthread_create consumer");
1437 ret = -1;
1438 goto error;
1439 }
1440
1441 /* Get time for sem_timedwait absolute timeout */
1442 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1443 if (ret < 0) {
1444 PERROR("clock_gettime spawn consumer");
1445 /* Infinite wait for the kconsumerd thread to be ready */
1446 ret = sem_wait(&consumer_data->sem);
1447 } else {
1448 /* Normal timeout if the gettime was successful */
1449 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1450 ret = sem_timedwait(&consumer_data->sem, &timeout);
1451 }
1452
1453 if (ret < 0) {
1454 if (errno == ETIMEDOUT) {
1455 /*
1456 * Call has timed out so we kill the kconsumerd_thread and return
1457 * an error.
1458 */
1459 ERR("The consumer thread was never ready. Killing it");
1460 ret = pthread_cancel(consumer_data->thread);
1461 if (ret < 0) {
1462 PERROR("pthread_cancel consumer thread");
1463 }
1464 } else {
1465 PERROR("semaphore wait failed consumer thread");
1466 }
1467 goto error;
1468 }
1469
1470 pthread_mutex_lock(&consumer_data->pid_mutex);
1471 if (consumer_data->pid == 0) {
1472 ERR("Kconsumerd did not start");
1473 pthread_mutex_unlock(&consumer_data->pid_mutex);
1474 goto error;
1475 }
1476 pthread_mutex_unlock(&consumer_data->pid_mutex);
1477
1478 return 0;
1479
1480 error:
1481 return ret;
1482 }
1483
1484 /*
1485 * Join consumer thread
1486 */
1487 static int join_consumer_thread(struct consumer_data *consumer_data)
1488 {
1489 void *status;
1490 int ret;
1491
1492 if (consumer_data->pid != 0) {
1493 ret = kill(consumer_data->pid, SIGTERM);
1494 if (ret) {
1495 ERR("Error killing consumer daemon");
1496 return ret;
1497 }
1498 return pthread_join(consumer_data->thread, &status);
1499 } else {
1500 return 0;
1501 }
1502 }
1503
1504 /*
1505 * Fork and exec a consumer daemon (consumerd).
1506 *
1507 * Return pid if successful else -1.
1508 */
1509 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1510 {
1511 int ret;
1512 pid_t pid;
1513 const char *consumer_to_use;
1514 const char *verbosity;
1515 struct stat st;
1516
1517 DBG("Spawning consumerd");
1518
1519 pid = fork();
1520 if (pid == 0) {
1521 /*
1522 * Exec consumerd.
1523 */
1524 if (opt_verbose_consumer) {
1525 verbosity = "--verbose";
1526 } else {
1527 verbosity = "--quiet";
1528 }
1529 switch (consumer_data->type) {
1530 case LTTNG_CONSUMER_KERNEL:
1531 /*
1532 * Find out which consumerd to execute. We will first try the
1533 * 64-bit path, then the sessiond's installation directory, and
1534 * fallback on the 32-bit one,
1535 */
1536 DBG3("Looking for a kernel consumer at these locations:");
1537 DBG3(" 1) %s", consumerd64_bin);
1538 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1539 DBG3(" 3) %s", consumerd32_bin);
1540 if (stat(consumerd64_bin, &st) == 0) {
1541 DBG3("Found location #1");
1542 consumer_to_use = consumerd64_bin;
1543 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1544 DBG3("Found location #2");
1545 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1546 } else if (stat(consumerd32_bin, &st) == 0) {
1547 DBG3("Found location #3");
1548 consumer_to_use = consumerd32_bin;
1549 } else {
1550 DBG("Could not find any valid consumerd executable");
1551 break;
1552 }
1553 DBG("Using kernel consumer at: %s", consumer_to_use);
1554 execl(consumer_to_use,
1555 "lttng-consumerd", verbosity, "-k",
1556 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1557 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1558 NULL);
1559 break;
1560 case LTTNG_CONSUMER64_UST:
1561 {
1562 char *tmpnew = NULL;
1563
1564 if (consumerd64_libdir[0] != '\0') {
1565 char *tmp;
1566 size_t tmplen;
1567
1568 tmp = getenv("LD_LIBRARY_PATH");
1569 if (!tmp) {
1570 tmp = "";
1571 }
1572 tmplen = strlen("LD_LIBRARY_PATH=")
1573 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1574 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1575 if (!tmpnew) {
1576 ret = -ENOMEM;
1577 goto error;
1578 }
1579 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1580 strcat(tmpnew, consumerd64_libdir);
1581 if (tmp[0] != '\0') {
1582 strcat(tmpnew, ":");
1583 strcat(tmpnew, tmp);
1584 }
1585 ret = putenv(tmpnew);
1586 if (ret) {
1587 ret = -errno;
1588 goto error;
1589 }
1590 }
1591 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1592 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1593 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1594 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1595 NULL);
1596 if (consumerd64_libdir[0] != '\0') {
1597 free(tmpnew);
1598 }
1599 if (ret) {
1600 goto error;
1601 }
1602 break;
1603 }
1604 case LTTNG_CONSUMER32_UST:
1605 {
1606 char *tmpnew = NULL;
1607
1608 if (consumerd32_libdir[0] != '\0') {
1609 char *tmp;
1610 size_t tmplen;
1611
1612 tmp = getenv("LD_LIBRARY_PATH");
1613 if (!tmp) {
1614 tmp = "";
1615 }
1616 tmplen = strlen("LD_LIBRARY_PATH=")
1617 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1618 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1619 if (!tmpnew) {
1620 ret = -ENOMEM;
1621 goto error;
1622 }
1623 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1624 strcat(tmpnew, consumerd32_libdir);
1625 if (tmp[0] != '\0') {
1626 strcat(tmpnew, ":");
1627 strcat(tmpnew, tmp);
1628 }
1629 ret = putenv(tmpnew);
1630 if (ret) {
1631 ret = -errno;
1632 goto error;
1633 }
1634 }
1635 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1636 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1637 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1638 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1639 NULL);
1640 if (consumerd32_libdir[0] != '\0') {
1641 free(tmpnew);
1642 }
1643 if (ret) {
1644 goto error;
1645 }
1646 break;
1647 }
1648 default:
1649 perror("unknown consumer type");
1650 exit(EXIT_FAILURE);
1651 }
1652 if (errno != 0) {
1653 perror("kernel start consumer exec");
1654 }
1655 exit(EXIT_FAILURE);
1656 } else if (pid > 0) {
1657 ret = pid;
1658 } else {
1659 perror("start consumer fork");
1660 ret = -errno;
1661 }
1662 error:
1663 return ret;
1664 }
1665
1666 /*
1667 * Spawn the consumerd daemon and session daemon thread.
1668 */
1669 static int start_consumerd(struct consumer_data *consumer_data)
1670 {
1671 int ret;
1672
1673 pthread_mutex_lock(&consumer_data->pid_mutex);
1674 if (consumer_data->pid != 0) {
1675 pthread_mutex_unlock(&consumer_data->pid_mutex);
1676 goto end;
1677 }
1678
1679 ret = spawn_consumerd(consumer_data);
1680 if (ret < 0) {
1681 ERR("Spawning consumerd failed");
1682 pthread_mutex_unlock(&consumer_data->pid_mutex);
1683 goto error;
1684 }
1685
1686 /* Setting up the consumer_data pid */
1687 consumer_data->pid = ret;
1688 DBG2("Consumer pid %d", consumer_data->pid);
1689 pthread_mutex_unlock(&consumer_data->pid_mutex);
1690
1691 DBG2("Spawning consumer control thread");
1692 ret = spawn_consumer_thread(consumer_data);
1693 if (ret < 0) {
1694 ERR("Fatal error spawning consumer control thread");
1695 goto error;
1696 }
1697
1698 end:
1699 return 0;
1700
1701 error:
1702 return ret;
1703 }
1704
1705 /*
1706 * modprobe_kernel_modules
1707 */
1708 static int modprobe_kernel_modules(void)
1709 {
1710 int ret = 0, i;
1711 char modprobe[256];
1712
1713 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1714 ret = snprintf(modprobe, sizeof(modprobe),
1715 "/sbin/modprobe %s%s",
1716 kernel_modules_list[i].required ? "" : "-q ",
1717 kernel_modules_list[i].name);
1718 if (ret < 0) {
1719 perror("snprintf modprobe");
1720 goto error;
1721 }
1722 modprobe[sizeof(modprobe) - 1] = '\0';
1723 ret = system(modprobe);
1724 if (ret == -1) {
1725 ERR("Unable to launch modprobe for module %s",
1726 kernel_modules_list[i].name);
1727 } else if (kernel_modules_list[i].required
1728 && WEXITSTATUS(ret) != 0) {
1729 ERR("Unable to load module %s",
1730 kernel_modules_list[i].name);
1731 } else {
1732 DBG("Modprobe successfully %s",
1733 kernel_modules_list[i].name);
1734 }
1735 }
1736
1737 error:
1738 return ret;
1739 }
1740
1741 /*
1742 * mount_debugfs
1743 */
1744 static int mount_debugfs(char *path)
1745 {
1746 int ret;
1747 char *type = "debugfs";
1748
1749 ret = run_as_mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1750 if (ret < 0) {
1751 PERROR("Cannot create debugfs path");
1752 goto error;
1753 }
1754
1755 ret = mount(type, path, type, 0, NULL);
1756 if (ret < 0) {
1757 PERROR("Cannot mount debugfs");
1758 goto error;
1759 }
1760
1761 DBG("Mounted debugfs successfully at %s", path);
1762
1763 error:
1764 return ret;
1765 }
1766
1767 /*
1768 * Setup necessary data for kernel tracer action.
1769 */
1770 static void init_kernel_tracer(void)
1771 {
1772 int ret;
1773 char *proc_mounts = "/proc/mounts";
1774 char line[256];
1775 char *debugfs_path = NULL, *lttng_path = NULL;
1776 FILE *fp;
1777
1778 /* Detect debugfs */
1779 fp = fopen(proc_mounts, "r");
1780 if (fp == NULL) {
1781 ERR("Unable to probe %s", proc_mounts);
1782 goto error;
1783 }
1784
1785 while (fgets(line, sizeof(line), fp) != NULL) {
1786 if (strstr(line, "debugfs") != NULL) {
1787 /* Remove first string */
1788 strtok(line, " ");
1789 /* Dup string here so we can reuse line later on */
1790 debugfs_path = strdup(strtok(NULL, " "));
1791 DBG("Got debugfs path : %s", debugfs_path);
1792 break;
1793 }
1794 }
1795
1796 fclose(fp);
1797
1798 /* Mount debugfs if needded */
1799 if (debugfs_path == NULL) {
1800 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1801 if (ret < 0) {
1802 perror("asprintf debugfs path");
1803 goto error;
1804 }
1805 ret = mount_debugfs(debugfs_path);
1806 if (ret < 0) {
1807 perror("Cannot mount debugfs");
1808 goto error;
1809 }
1810 }
1811
1812 /* Modprobe lttng kernel modules */
1813 ret = modprobe_kernel_modules();
1814 if (ret < 0) {
1815 goto error;
1816 }
1817
1818 /* Setup lttng kernel path */
1819 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1820 if (ret < 0) {
1821 perror("asprintf lttng path");
1822 goto error;
1823 }
1824
1825 /* Open debugfs lttng */
1826 kernel_tracer_fd = open(lttng_path, O_RDWR);
1827 if (kernel_tracer_fd < 0) {
1828 DBG("Failed to open %s", lttng_path);
1829 goto error;
1830 }
1831
1832 free(lttng_path);
1833 free(debugfs_path);
1834 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1835 return;
1836
1837 error:
1838 if (lttng_path) {
1839 free(lttng_path);
1840 }
1841 if (debugfs_path) {
1842 free(debugfs_path);
1843 }
1844 WARN("No kernel tracer available");
1845 kernel_tracer_fd = 0;
1846 return;
1847 }
1848
1849 /*
1850 * Init tracing by creating trace directory and sending fds kernel consumer.
1851 */
1852 static int init_kernel_tracing(struct ltt_kernel_session *session)
1853 {
1854 int ret = 0;
1855
1856 if (session->consumer_fds_sent == 0) {
1857 /*
1858 * Assign default kernel consumer socket if no consumer assigned to the
1859 * kernel session. At this point, it's NOT suppose to be 0 but this is
1860 * an extra security check.
1861 */
1862 if (session->consumer_fd == 0) {
1863 session->consumer_fd = kconsumer_data.cmd_sock;
1864 }
1865
1866 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1867 if (ret < 0) {
1868 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1869 goto error;
1870 }
1871
1872 session->consumer_fds_sent = 1;
1873 }
1874
1875 error:
1876 return ret;
1877 }
1878
1879 /*
1880 * Create an UST session and add it to the session ust list.
1881 */
1882 static int create_ust_session(struct ltt_session *session,
1883 struct lttng_domain *domain)
1884 {
1885 struct ltt_ust_session *lus = NULL;
1886 int ret;
1887
1888 switch (domain->type) {
1889 case LTTNG_DOMAIN_UST:
1890 break;
1891 default:
1892 ret = LTTCOMM_UNKNOWN_DOMAIN;
1893 goto error;
1894 }
1895
1896 DBG("Creating UST session");
1897
1898 lus = trace_ust_create_session(session->path, session->id, domain);
1899 if (lus == NULL) {
1900 ret = LTTCOMM_UST_SESS_FAIL;
1901 goto error;
1902 }
1903
1904 ret = run_as_mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1905 session->uid, session->gid);
1906 if (ret < 0) {
1907 if (ret != -EEXIST) {
1908 ERR("Trace directory creation error");
1909 ret = LTTCOMM_UST_SESS_FAIL;
1910 goto error;
1911 }
1912 }
1913
1914 /* The domain type dictate different actions on session creation */
1915 switch (domain->type) {
1916 case LTTNG_DOMAIN_UST:
1917 /* No ustctl for the global UST domain */
1918 break;
1919 default:
1920 ERR("Unknown UST domain on create session %d", domain->type);
1921 goto error;
1922 }
1923 lus->uid = session->uid;
1924 lus->gid = session->gid;
1925 session->ust_session = lus;
1926
1927 return LTTCOMM_OK;
1928
1929 error:
1930 free(lus);
1931 return ret;
1932 }
1933
1934 /*
1935 * Create a kernel tracer session then create the default channel.
1936 */
1937 static int create_kernel_session(struct ltt_session *session)
1938 {
1939 int ret;
1940
1941 DBG("Creating kernel session");
1942
1943 ret = kernel_create_session(session, kernel_tracer_fd);
1944 if (ret < 0) {
1945 ret = LTTCOMM_KERN_SESS_FAIL;
1946 goto error;
1947 }
1948
1949 /* Set kernel consumer socket fd */
1950 if (kconsumer_data.cmd_sock) {
1951 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1952 }
1953
1954 ret = run_as_mkdir_recursive(session->kernel_session->trace_path,
1955 S_IRWXU | S_IRWXG, session->uid, session->gid);
1956 if (ret < 0) {
1957 if (ret != -EEXIST) {
1958 ERR("Trace directory creation error");
1959 goto error;
1960 }
1961 }
1962 session->kernel_session->uid = session->uid;
1963 session->kernel_session->gid = session->gid;
1964
1965 error:
1966 return ret;
1967 }
1968
1969 /*
1970 * Check if the UID or GID match the session. Root user has access to all
1971 * sessions.
1972 */
1973 static int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid)
1974 {
1975 if (uid != session->uid && gid != session->gid && uid != 0) {
1976 return 0;
1977 } else {
1978 return 1;
1979 }
1980 }
1981
1982 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
1983 {
1984 unsigned int i = 0;
1985 struct ltt_session *session;
1986
1987 DBG("Counting number of available session for UID %d GID %d",
1988 uid, gid);
1989 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1990 /*
1991 * Only list the sessions the user can control.
1992 */
1993 if (!session_access_ok(session, uid, gid)) {
1994 continue;
1995 }
1996 i++;
1997 }
1998 return i;
1999 }
2000
2001 /*
2002 * Using the session list, filled a lttng_session array to send back to the
2003 * client for session listing.
2004 *
2005 * The session list lock MUST be acquired before calling this function. Use
2006 * session_lock_list() and session_unlock_list().
2007 */
2008 static void list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2009 gid_t gid)
2010 {
2011 unsigned int i = 0;
2012 struct ltt_session *session;
2013
2014 DBG("Getting all available session for UID %d GID %d",
2015 uid, gid);
2016 /*
2017 * Iterate over session list and append data after the control struct in
2018 * the buffer.
2019 */
2020 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2021 /*
2022 * Only list the sessions the user can control.
2023 */
2024 if (!session_access_ok(session, uid, gid)) {
2025 continue;
2026 }
2027 strncpy(sessions[i].path, session->path, PATH_MAX);
2028 sessions[i].path[PATH_MAX - 1] = '\0';
2029 strncpy(sessions[i].name, session->name, NAME_MAX);
2030 sessions[i].name[NAME_MAX - 1] = '\0';
2031 sessions[i].enabled = session->enabled;
2032 i++;
2033 }
2034 }
2035
2036 /*
2037 * Fill lttng_channel array of all channels.
2038 */
2039 static void list_lttng_channels(int domain, struct ltt_session *session,
2040 struct lttng_channel *channels)
2041 {
2042 int i = 0;
2043 struct ltt_kernel_channel *kchan;
2044
2045 DBG("Listing channels for session %s", session->name);
2046
2047 switch (domain) {
2048 case LTTNG_DOMAIN_KERNEL:
2049 /* Kernel channels */
2050 if (session->kernel_session != NULL) {
2051 cds_list_for_each_entry(kchan,
2052 &session->kernel_session->channel_list.head, list) {
2053 /* Copy lttng_channel struct to array */
2054 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2055 channels[i].enabled = kchan->enabled;
2056 i++;
2057 }
2058 }
2059 break;
2060 case LTTNG_DOMAIN_UST:
2061 {
2062 struct lttng_ht_iter iter;
2063 struct ltt_ust_channel *uchan;
2064
2065 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
2066 &iter.iter, uchan, node.node) {
2067 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2068 channels[i].attr.overwrite = uchan->attr.overwrite;
2069 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2070 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2071 channels[i].attr.switch_timer_interval =
2072 uchan->attr.switch_timer_interval;
2073 channels[i].attr.read_timer_interval =
2074 uchan->attr.read_timer_interval;
2075 channels[i].enabled = uchan->enabled;
2076 switch (uchan->attr.output) {
2077 case LTTNG_UST_MMAP:
2078 default:
2079 channels[i].attr.output = LTTNG_EVENT_MMAP;
2080 break;
2081 }
2082 i++;
2083 }
2084 break;
2085 }
2086 default:
2087 break;
2088 }
2089 }
2090
2091 /*
2092 * Create a list of ust global domain events.
2093 */
2094 static int list_lttng_ust_global_events(char *channel_name,
2095 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2096 {
2097 int i = 0, ret = 0;
2098 unsigned int nb_event = 0;
2099 struct lttng_ht_iter iter;
2100 struct lttng_ht_node_str *node;
2101 struct ltt_ust_channel *uchan;
2102 struct ltt_ust_event *uevent;
2103 struct lttng_event *tmp;
2104
2105 DBG("Listing UST global events for channel %s", channel_name);
2106
2107 rcu_read_lock();
2108
2109 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2110 node = lttng_ht_iter_get_node_str(&iter);
2111 if (node == NULL) {
2112 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2113 goto error;
2114 }
2115
2116 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2117
2118 nb_event += lttng_ht_get_count(uchan->events);
2119
2120 if (nb_event == 0) {
2121 ret = nb_event;
2122 goto error;
2123 }
2124
2125 DBG3("Listing UST global %d events", nb_event);
2126
2127 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2128 if (tmp == NULL) {
2129 ret = -LTTCOMM_FATAL;
2130 goto error;
2131 }
2132
2133 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2134 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2135 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2136 tmp[i].enabled = uevent->enabled;
2137 switch (uevent->attr.instrumentation) {
2138 case LTTNG_UST_TRACEPOINT:
2139 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2140 break;
2141 case LTTNG_UST_PROBE:
2142 tmp[i].type = LTTNG_EVENT_PROBE;
2143 break;
2144 case LTTNG_UST_FUNCTION:
2145 tmp[i].type = LTTNG_EVENT_FUNCTION;
2146 break;
2147 case LTTNG_UST_TRACEPOINT_LOGLEVEL:
2148 tmp[i].type = LTTNG_EVENT_TRACEPOINT_LOGLEVEL;
2149 break;
2150 }
2151 i++;
2152 }
2153
2154 ret = nb_event;
2155 *events = tmp;
2156
2157 error:
2158 rcu_read_unlock();
2159 return ret;
2160 }
2161
2162 /*
2163 * Fill lttng_event array of all kernel events in the channel.
2164 */
2165 static int list_lttng_kernel_events(char *channel_name,
2166 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2167 {
2168 int i = 0, ret;
2169 unsigned int nb_event;
2170 struct ltt_kernel_event *event;
2171 struct ltt_kernel_channel *kchan;
2172
2173 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2174 if (kchan == NULL) {
2175 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2176 goto error;
2177 }
2178
2179 nb_event = kchan->event_count;
2180
2181 DBG("Listing events for channel %s", kchan->channel->name);
2182
2183 if (nb_event == 0) {
2184 ret = nb_event;
2185 goto error;
2186 }
2187
2188 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2189 if (*events == NULL) {
2190 ret = LTTCOMM_FATAL;
2191 goto error;
2192 }
2193
2194 /* Kernel channels */
2195 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2196 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2197 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2198 (*events)[i].enabled = event->enabled;
2199 switch (event->event->instrumentation) {
2200 case LTTNG_KERNEL_TRACEPOINT:
2201 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2202 break;
2203 case LTTNG_KERNEL_KPROBE:
2204 case LTTNG_KERNEL_KRETPROBE:
2205 (*events)[i].type = LTTNG_EVENT_PROBE;
2206 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2207 sizeof(struct lttng_kernel_kprobe));
2208 break;
2209 case LTTNG_KERNEL_FUNCTION:
2210 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2211 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2212 sizeof(struct lttng_kernel_function));
2213 break;
2214 case LTTNG_KERNEL_NOOP:
2215 (*events)[i].type = LTTNG_EVENT_NOOP;
2216 break;
2217 case LTTNG_KERNEL_SYSCALL:
2218 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2219 break;
2220 case LTTNG_KERNEL_ALL:
2221 assert(0);
2222 break;
2223 }
2224 i++;
2225 }
2226
2227 return nb_event;
2228
2229 error:
2230 return ret;
2231 }
2232
2233 /*
2234 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2235 */
2236 static int cmd_disable_channel(struct ltt_session *session,
2237 int domain, char *channel_name)
2238 {
2239 int ret;
2240 struct ltt_ust_session *usess;
2241
2242 usess = session->ust_session;
2243
2244 switch (domain) {
2245 case LTTNG_DOMAIN_KERNEL:
2246 {
2247 ret = channel_kernel_disable(session->kernel_session,
2248 channel_name);
2249 if (ret != LTTCOMM_OK) {
2250 goto error;
2251 }
2252
2253 kernel_wait_quiescent(kernel_tracer_fd);
2254 break;
2255 }
2256 case LTTNG_DOMAIN_UST:
2257 {
2258 struct ltt_ust_channel *uchan;
2259 struct lttng_ht *chan_ht;
2260
2261 chan_ht = usess->domain_global.channels;
2262
2263 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2264 if (uchan == NULL) {
2265 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2266 goto error;
2267 }
2268
2269 ret = channel_ust_disable(usess, domain, uchan);
2270 if (ret != LTTCOMM_OK) {
2271 goto error;
2272 }
2273 break;
2274 }
2275 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2276 case LTTNG_DOMAIN_UST_EXEC_NAME:
2277 case LTTNG_DOMAIN_UST_PID:
2278 ret = LTTCOMM_NOT_IMPLEMENTED;
2279 goto error;
2280 default:
2281 ret = LTTCOMM_UNKNOWN_DOMAIN;
2282 goto error;
2283 }
2284
2285 ret = LTTCOMM_OK;
2286
2287 error:
2288 return ret;
2289 }
2290
2291 /*
2292 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2293 */
2294 static int cmd_enable_channel(struct ltt_session *session,
2295 int domain, struct lttng_channel *attr)
2296 {
2297 int ret;
2298 struct ltt_ust_session *usess = session->ust_session;
2299 struct lttng_ht *chan_ht;
2300
2301 DBG("Enabling channel %s for session %s", attr->name, session->name);
2302
2303 switch (domain) {
2304 case LTTNG_DOMAIN_KERNEL:
2305 {
2306 struct ltt_kernel_channel *kchan;
2307
2308 kchan = trace_kernel_get_channel_by_name(attr->name,
2309 session->kernel_session);
2310 if (kchan == NULL) {
2311 ret = channel_kernel_create(session->kernel_session,
2312 attr, kernel_poll_pipe[1]);
2313 } else {
2314 ret = channel_kernel_enable(session->kernel_session, kchan);
2315 }
2316
2317 if (ret != LTTCOMM_OK) {
2318 goto error;
2319 }
2320
2321 kernel_wait_quiescent(kernel_tracer_fd);
2322 break;
2323 }
2324 case LTTNG_DOMAIN_UST:
2325 {
2326 struct ltt_ust_channel *uchan;
2327
2328 chan_ht = usess->domain_global.channels;
2329
2330 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2331 if (uchan == NULL) {
2332 ret = channel_ust_create(usess, domain, attr);
2333 } else {
2334 ret = channel_ust_enable(usess, domain, uchan);
2335 }
2336 break;
2337 }
2338 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2339 case LTTNG_DOMAIN_UST_EXEC_NAME:
2340 case LTTNG_DOMAIN_UST_PID:
2341 ret = LTTCOMM_NOT_IMPLEMENTED;
2342 goto error;
2343 default:
2344 ret = LTTCOMM_UNKNOWN_DOMAIN;
2345 goto error;
2346 }
2347
2348 error:
2349 return ret;
2350 }
2351
2352 /*
2353 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2354 */
2355 static int cmd_disable_event(struct ltt_session *session, int domain,
2356 char *channel_name, char *event_name)
2357 {
2358 int ret;
2359
2360 switch (domain) {
2361 case LTTNG_DOMAIN_KERNEL:
2362 {
2363 struct ltt_kernel_channel *kchan;
2364 struct ltt_kernel_session *ksess;
2365
2366 ksess = session->kernel_session;
2367
2368 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2369 if (kchan == NULL) {
2370 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2371 goto error;
2372 }
2373
2374 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2375 if (ret != LTTCOMM_OK) {
2376 goto error;
2377 }
2378
2379 kernel_wait_quiescent(kernel_tracer_fd);
2380 break;
2381 }
2382 case LTTNG_DOMAIN_UST:
2383 {
2384 struct ltt_ust_channel *uchan;
2385 struct ltt_ust_session *usess;
2386
2387 usess = session->ust_session;
2388
2389 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2390 channel_name);
2391 if (uchan == NULL) {
2392 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2393 goto error;
2394 }
2395
2396 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2397 if (ret != LTTCOMM_OK) {
2398 goto error;
2399 }
2400
2401 DBG3("Disable UST event %s in channel %s completed", event_name,
2402 channel_name);
2403 break;
2404 }
2405 case LTTNG_DOMAIN_UST_EXEC_NAME:
2406 case LTTNG_DOMAIN_UST_PID:
2407 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2408 default:
2409 ret = LTTCOMM_NOT_IMPLEMENTED;
2410 goto error;
2411 }
2412
2413 ret = LTTCOMM_OK;
2414
2415 error:
2416 return ret;
2417 }
2418
2419 /*
2420 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2421 */
2422 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2423 char *channel_name)
2424 {
2425 int ret;
2426
2427 switch (domain) {
2428 case LTTNG_DOMAIN_KERNEL:
2429 {
2430 struct ltt_kernel_session *ksess;
2431 struct ltt_kernel_channel *kchan;
2432
2433 ksess = session->kernel_session;
2434
2435 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2436 if (kchan == NULL) {
2437 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2438 goto error;
2439 }
2440
2441 ret = event_kernel_disable_all(ksess, kchan);
2442 if (ret != LTTCOMM_OK) {
2443 goto error;
2444 }
2445
2446 kernel_wait_quiescent(kernel_tracer_fd);
2447 break;
2448 }
2449 case LTTNG_DOMAIN_UST:
2450 {
2451 struct ltt_ust_session *usess;
2452 struct ltt_ust_channel *uchan;
2453
2454 usess = session->ust_session;
2455
2456 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2457 channel_name);
2458 if (uchan == NULL) {
2459 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2460 goto error;
2461 }
2462
2463 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2464 if (ret != 0) {
2465 goto error;
2466 }
2467
2468 DBG3("Disable all UST events in channel %s completed", channel_name);
2469
2470 break;
2471 }
2472 case LTTNG_DOMAIN_UST_EXEC_NAME:
2473 case LTTNG_DOMAIN_UST_PID:
2474 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2475 default:
2476 ret = LTTCOMM_NOT_IMPLEMENTED;
2477 goto error;
2478 }
2479
2480 ret = LTTCOMM_OK;
2481
2482 error:
2483 return ret;
2484 }
2485
2486 /*
2487 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2488 */
2489 static int cmd_add_context(struct ltt_session *session, int domain,
2490 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2491 {
2492 int ret;
2493
2494 switch (domain) {
2495 case LTTNG_DOMAIN_KERNEL:
2496 /* Add kernel context to kernel tracer */
2497 ret = context_kernel_add(session->kernel_session, ctx,
2498 event_name, channel_name);
2499 if (ret != LTTCOMM_OK) {
2500 goto error;
2501 }
2502 break;
2503 case LTTNG_DOMAIN_UST:
2504 {
2505 struct ltt_ust_session *usess = session->ust_session;
2506
2507 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2508 if (ret != LTTCOMM_OK) {
2509 goto error;
2510 }
2511 break;
2512 }
2513 case LTTNG_DOMAIN_UST_EXEC_NAME:
2514 case LTTNG_DOMAIN_UST_PID:
2515 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2516 default:
2517 ret = LTTCOMM_NOT_IMPLEMENTED;
2518 goto error;
2519 }
2520
2521 ret = LTTCOMM_OK;
2522
2523 error:
2524 return ret;
2525 }
2526
2527 /*
2528 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2529 *
2530 * TODO: currently, both events and loglevels are kept within the same
2531 * namespace for UST global registry/app registery, so if an event
2532 * happen to have the same name as the loglevel (very unlikely though),
2533 * and an attempt is made to enable/disable both in the same session,
2534 * the first to be created will be the only one allowed to exist.
2535 */
2536 static int cmd_enable_event(struct ltt_session *session, int domain,
2537 char *channel_name, struct lttng_event *event)
2538 {
2539 int ret;
2540 struct lttng_channel *attr;
2541 struct ltt_ust_session *usess = session->ust_session;
2542
2543 switch (domain) {
2544 case LTTNG_DOMAIN_KERNEL:
2545 {
2546 struct ltt_kernel_channel *kchan;
2547
2548 kchan = trace_kernel_get_channel_by_name(channel_name,
2549 session->kernel_session);
2550 if (kchan == NULL) {
2551 attr = channel_new_default_attr(domain);
2552 if (attr == NULL) {
2553 ret = LTTCOMM_FATAL;
2554 goto error;
2555 }
2556 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2557
2558 /* This call will notify the kernel thread */
2559 ret = channel_kernel_create(session->kernel_session,
2560 attr, kernel_poll_pipe[1]);
2561 if (ret != LTTCOMM_OK) {
2562 free(attr);
2563 goto error;
2564 }
2565 free(attr);
2566 }
2567
2568 /* Get the newly created kernel channel pointer */
2569 kchan = trace_kernel_get_channel_by_name(channel_name,
2570 session->kernel_session);
2571 if (kchan == NULL) {
2572 /* This sould not happen... */
2573 ret = LTTCOMM_FATAL;
2574 goto error;
2575 }
2576
2577 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2578 event);
2579 if (ret != LTTCOMM_OK) {
2580 goto error;
2581 }
2582
2583 kernel_wait_quiescent(kernel_tracer_fd);
2584 break;
2585 }
2586 case LTTNG_DOMAIN_UST:
2587 {
2588 struct lttng_channel *attr;
2589 struct ltt_ust_channel *uchan;
2590
2591 /* Get channel from global UST domain */
2592 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2593 channel_name);
2594 if (uchan == NULL) {
2595 /* Create default channel */
2596 attr = channel_new_default_attr(domain);
2597 if (attr == NULL) {
2598 ret = LTTCOMM_FATAL;
2599 goto error;
2600 }
2601 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2602 attr->name[NAME_MAX - 1] = '\0';
2603
2604 ret = channel_ust_create(usess, domain, attr);
2605 if (ret != LTTCOMM_OK) {
2606 free(attr);
2607 goto error;
2608 }
2609 free(attr);
2610
2611 /* Get the newly created channel reference back */
2612 uchan = trace_ust_find_channel_by_name(
2613 usess->domain_global.channels, channel_name);
2614 if (uchan == NULL) {
2615 /* Something is really wrong */
2616 ret = LTTCOMM_FATAL;
2617 goto error;
2618 }
2619 }
2620
2621 /* At this point, the session and channel exist on the tracer */
2622 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2623 if (ret != LTTCOMM_OK) {
2624 goto error;
2625 }
2626 break;
2627 }
2628 case LTTNG_DOMAIN_UST_EXEC_NAME:
2629 case LTTNG_DOMAIN_UST_PID:
2630 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2631 default:
2632 ret = LTTCOMM_NOT_IMPLEMENTED;
2633 goto error;
2634 }
2635
2636 ret = LTTCOMM_OK;
2637
2638 error:
2639 return ret;
2640 }
2641
2642 /*
2643 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2644 */
2645 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2646 char *channel_name, int event_type)
2647 {
2648 int ret;
2649 struct ltt_kernel_channel *kchan;
2650
2651 switch (domain) {
2652 case LTTNG_DOMAIN_KERNEL:
2653 kchan = trace_kernel_get_channel_by_name(channel_name,
2654 session->kernel_session);
2655 if (kchan == NULL) {
2656 /* This call will notify the kernel thread */
2657 ret = channel_kernel_create(session->kernel_session, NULL,
2658 kernel_poll_pipe[1]);
2659 if (ret != LTTCOMM_OK) {
2660 goto error;
2661 }
2662
2663 /* Get the newly created kernel channel pointer */
2664 kchan = trace_kernel_get_channel_by_name(channel_name,
2665 session->kernel_session);
2666 if (kchan == NULL) {
2667 /* This sould not happen... */
2668 ret = LTTCOMM_FATAL;
2669 goto error;
2670 }
2671
2672 }
2673
2674 switch (event_type) {
2675 case LTTNG_EVENT_SYSCALL:
2676 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2677 kchan, kernel_tracer_fd);
2678 break;
2679 case LTTNG_EVENT_TRACEPOINT:
2680 /*
2681 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2682 * events already registered to the channel.
2683 */
2684 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2685 kchan, kernel_tracer_fd);
2686 break;
2687 case LTTNG_EVENT_ALL:
2688 /* Enable syscalls and tracepoints */
2689 ret = event_kernel_enable_all(session->kernel_session,
2690 kchan, kernel_tracer_fd);
2691 break;
2692 default:
2693 ret = LTTCOMM_KERN_ENABLE_FAIL;
2694 goto error;
2695 }
2696
2697 /* Manage return value */
2698 if (ret != LTTCOMM_OK) {
2699 goto error;
2700 }
2701
2702 kernel_wait_quiescent(kernel_tracer_fd);
2703 break;
2704 case LTTNG_DOMAIN_UST:
2705 {
2706 struct lttng_channel *attr;
2707 struct ltt_ust_channel *uchan;
2708 struct ltt_ust_session *usess = session->ust_session;
2709
2710 /* Get channel from global UST domain */
2711 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2712 channel_name);
2713 if (uchan == NULL) {
2714 /* Create default channel */
2715 attr = channel_new_default_attr(domain);
2716 if (attr == NULL) {
2717 ret = LTTCOMM_FATAL;
2718 goto error;
2719 }
2720 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2721 attr->name[NAME_MAX - 1] = '\0';
2722
2723 /* Use the internal command enable channel */
2724 ret = channel_ust_create(usess, domain, attr);
2725 if (ret != LTTCOMM_OK) {
2726 free(attr);
2727 goto error;
2728 }
2729 free(attr);
2730
2731 /* Get the newly created channel reference back */
2732 uchan = trace_ust_find_channel_by_name(
2733 usess->domain_global.channels, channel_name);
2734 if (uchan == NULL) {
2735 /* Something is really wrong */
2736 ret = LTTCOMM_FATAL;
2737 goto error;
2738 }
2739 }
2740
2741 /* At this point, the session and channel exist on the tracer */
2742
2743 switch (event_type) {
2744 case LTTNG_EVENT_ALL:
2745 case LTTNG_EVENT_TRACEPOINT:
2746 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2747 if (ret != LTTCOMM_OK) {
2748 goto error;
2749 }
2750 break;
2751 default:
2752 ret = LTTCOMM_UST_ENABLE_FAIL;
2753 goto error;
2754 }
2755
2756 /* Manage return value */
2757 if (ret != LTTCOMM_OK) {
2758 goto error;
2759 }
2760
2761 break;
2762 }
2763 case LTTNG_DOMAIN_UST_EXEC_NAME:
2764 case LTTNG_DOMAIN_UST_PID:
2765 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2766 default:
2767 ret = LTTCOMM_NOT_IMPLEMENTED;
2768 goto error;
2769 }
2770
2771 ret = LTTCOMM_OK;
2772
2773 error:
2774 return ret;
2775 }
2776
2777 /*
2778 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2779 */
2780 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2781 {
2782 int ret;
2783 ssize_t nb_events = 0;
2784
2785 switch (domain) {
2786 case LTTNG_DOMAIN_KERNEL:
2787 nb_events = kernel_list_events(kernel_tracer_fd, events);
2788 if (nb_events < 0) {
2789 ret = LTTCOMM_KERN_LIST_FAIL;
2790 goto error;
2791 }
2792 break;
2793 case LTTNG_DOMAIN_UST:
2794 nb_events = ust_app_list_events(events);
2795 if (nb_events < 0) {
2796 ret = LTTCOMM_UST_LIST_FAIL;
2797 goto error;
2798 }
2799 break;
2800 default:
2801 ret = LTTCOMM_NOT_IMPLEMENTED;
2802 goto error;
2803 }
2804
2805 return nb_events;
2806
2807 error:
2808 /* Return negative value to differentiate return code */
2809 return -ret;
2810 }
2811
2812 /*
2813 * Command LTTNG_START_TRACE processed by the client thread.
2814 */
2815 static int cmd_start_trace(struct ltt_session *session)
2816 {
2817 int ret;
2818 struct ltt_kernel_session *ksession;
2819 struct ltt_ust_session *usess;
2820
2821 /* Short cut */
2822 ksession = session->kernel_session;
2823 usess = session->ust_session;
2824
2825 if (session->enabled) {
2826 ret = LTTCOMM_UST_START_FAIL;
2827 goto error;
2828 }
2829
2830 session->enabled = 1;
2831
2832 /* Kernel tracing */
2833 if (ksession != NULL) {
2834 struct ltt_kernel_channel *kchan;
2835
2836 /* Open kernel metadata */
2837 if (ksession->metadata == NULL) {
2838 ret = kernel_open_metadata(ksession, ksession->trace_path);
2839 if (ret < 0) {
2840 ret = LTTCOMM_KERN_META_FAIL;
2841 goto error;
2842 }
2843 }
2844
2845 /* Open kernel metadata stream */
2846 if (ksession->metadata_stream_fd == 0) {
2847 ret = kernel_open_metadata_stream(ksession);
2848 if (ret < 0) {
2849 ERR("Kernel create metadata stream failed");
2850 ret = LTTCOMM_KERN_STREAM_FAIL;
2851 goto error;
2852 }
2853 }
2854
2855 /* For each channel */
2856 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2857 if (kchan->stream_count == 0) {
2858 ret = kernel_open_channel_stream(kchan);
2859 if (ret < 0) {
2860 ret = LTTCOMM_KERN_STREAM_FAIL;
2861 goto error;
2862 }
2863 /* Update the stream global counter */
2864 ksession->stream_count_global += ret;
2865 }
2866 }
2867
2868 /* Setup kernel consumer socket and send fds to it */
2869 ret = init_kernel_tracing(ksession);
2870 if (ret < 0) {
2871 ret = LTTCOMM_KERN_START_FAIL;
2872 goto error;
2873 }
2874
2875 /* This start the kernel tracing */
2876 ret = kernel_start_session(ksession);
2877 if (ret < 0) {
2878 ret = LTTCOMM_KERN_START_FAIL;
2879 goto error;
2880 }
2881
2882 /* Quiescent wait after starting trace */
2883 kernel_wait_quiescent(kernel_tracer_fd);
2884 }
2885
2886 /* Flag session that trace should start automatically */
2887 if (usess) {
2888 usess->start_trace = 1;
2889
2890 ret = ust_app_start_trace_all(usess);
2891 if (ret < 0) {
2892 ret = LTTCOMM_UST_START_FAIL;
2893 goto error;
2894 }
2895 }
2896
2897 ret = LTTCOMM_OK;
2898
2899 error:
2900 return ret;
2901 }
2902
2903 /*
2904 * Command LTTNG_STOP_TRACE processed by the client thread.
2905 */
2906 static int cmd_stop_trace(struct ltt_session *session)
2907 {
2908 int ret;
2909 struct ltt_kernel_channel *kchan;
2910 struct ltt_kernel_session *ksession;
2911 struct ltt_ust_session *usess;
2912
2913 /* Short cut */
2914 ksession = session->kernel_session;
2915 usess = session->ust_session;
2916
2917 if (!session->enabled) {
2918 ret = LTTCOMM_UST_STOP_FAIL;
2919 goto error;
2920 }
2921
2922 session->enabled = 0;
2923
2924 /* Kernel tracer */
2925 if (ksession != NULL) {
2926 DBG("Stop kernel tracing");
2927
2928 /* Flush all buffers before stopping */
2929 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2930 if (ret < 0) {
2931 ERR("Kernel metadata flush failed");
2932 }
2933
2934 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2935 ret = kernel_flush_buffer(kchan);
2936 if (ret < 0) {
2937 ERR("Kernel flush buffer error");
2938 }
2939 }
2940
2941 ret = kernel_stop_session(ksession);
2942 if (ret < 0) {
2943 ret = LTTCOMM_KERN_STOP_FAIL;
2944 goto error;
2945 }
2946
2947 kernel_wait_quiescent(kernel_tracer_fd);
2948 }
2949
2950 if (usess) {
2951 usess->start_trace = 0;
2952
2953 ret = ust_app_stop_trace_all(usess);
2954 if (ret < 0) {
2955 ret = LTTCOMM_UST_STOP_FAIL;
2956 goto error;
2957 }
2958 }
2959
2960 ret = LTTCOMM_OK;
2961
2962 error:
2963 return ret;
2964 }
2965
2966 /*
2967 * Command LTTNG_CREATE_SESSION processed by the client thread.
2968 */
2969 static int cmd_create_session(char *name, char *path, struct ucred *creds)
2970 {
2971 int ret;
2972
2973 ret = session_create(name, path, creds->uid, creds->gid);
2974 if (ret != LTTCOMM_OK) {
2975 goto error;
2976 }
2977
2978 ret = LTTCOMM_OK;
2979
2980 error:
2981 return ret;
2982 }
2983
2984 /*
2985 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2986 */
2987 static int cmd_destroy_session(struct ltt_session *session, char *name)
2988 {
2989 int ret;
2990
2991 /* Clean kernel session teardown */
2992 teardown_kernel_session(session);
2993 /* UST session teardown */
2994 teardown_ust_session(session);
2995
2996 /*
2997 * Must notify the kernel thread here to update it's poll setin order
2998 * to remove the channel(s)' fd just destroyed.
2999 */
3000 ret = notify_thread_pipe(kernel_poll_pipe[1]);
3001 if (ret < 0) {
3002 perror("write kernel poll pipe");
3003 }
3004
3005 ret = session_destroy(session);
3006
3007 return ret;
3008 }
3009
3010 /*
3011 * Command LTTNG_CALIBRATE processed by the client thread.
3012 */
3013 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3014 {
3015 int ret;
3016
3017 switch (domain) {
3018 case LTTNG_DOMAIN_KERNEL:
3019 {
3020 struct lttng_kernel_calibrate kcalibrate;
3021
3022 kcalibrate.type = calibrate->type;
3023 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3024 if (ret < 0) {
3025 ret = LTTCOMM_KERN_ENABLE_FAIL;
3026 goto error;
3027 }
3028 break;
3029 }
3030 default:
3031 /* TODO: Userspace tracing */
3032 ret = LTTCOMM_NOT_IMPLEMENTED;
3033 goto error;
3034 }
3035
3036 ret = LTTCOMM_OK;
3037
3038 error:
3039 return ret;
3040 }
3041
3042 /*
3043 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3044 */
3045 static int cmd_register_consumer(struct ltt_session *session, int domain,
3046 char *sock_path)
3047 {
3048 int ret, sock;
3049
3050 switch (domain) {
3051 case LTTNG_DOMAIN_KERNEL:
3052 /* Can't register a consumer if there is already one */
3053 if (session->kernel_session->consumer_fds_sent != 0) {
3054 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3055 goto error;
3056 }
3057
3058 sock = lttcomm_connect_unix_sock(sock_path);
3059 if (sock < 0) {
3060 ret = LTTCOMM_CONNECT_FAIL;
3061 goto error;
3062 }
3063
3064 session->kernel_session->consumer_fd = sock;
3065 break;
3066 default:
3067 /* TODO: Userspace tracing */
3068 ret = LTTCOMM_NOT_IMPLEMENTED;
3069 goto error;
3070 }
3071
3072 ret = LTTCOMM_OK;
3073
3074 error:
3075 return ret;
3076 }
3077
3078 /*
3079 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3080 */
3081 static ssize_t cmd_list_domains(struct ltt_session *session,
3082 struct lttng_domain **domains)
3083 {
3084 int ret, index = 0;
3085 ssize_t nb_dom = 0;
3086
3087 if (session->kernel_session != NULL) {
3088 DBG3("Listing domains found kernel domain");
3089 nb_dom++;
3090 }
3091
3092 if (session->ust_session != NULL) {
3093 DBG3("Listing domains found UST global domain");
3094 nb_dom++;
3095 }
3096
3097 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3098 if (*domains == NULL) {
3099 ret = -LTTCOMM_FATAL;
3100 goto error;
3101 }
3102
3103 if (session->kernel_session != NULL) {
3104 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3105 index++;
3106 }
3107
3108 if (session->ust_session != NULL) {
3109 (*domains)[index].type = LTTNG_DOMAIN_UST;
3110 index++;
3111 }
3112
3113 return nb_dom;
3114
3115 error:
3116 return ret;
3117 }
3118
3119 /*
3120 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3121 */
3122 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3123 struct lttng_channel **channels)
3124 {
3125 int ret;
3126 ssize_t nb_chan = 0;
3127
3128 switch (domain) {
3129 case LTTNG_DOMAIN_KERNEL:
3130 if (session->kernel_session != NULL) {
3131 nb_chan = session->kernel_session->channel_count;
3132 }
3133 DBG3("Number of kernel channels %zd", nb_chan);
3134 break;
3135 case LTTNG_DOMAIN_UST:
3136 if (session->ust_session != NULL) {
3137 nb_chan = lttng_ht_get_count(
3138 session->ust_session->domain_global.channels);
3139 }
3140 DBG3("Number of UST global channels %zd", nb_chan);
3141 break;
3142 default:
3143 *channels = NULL;
3144 ret = -LTTCOMM_NOT_IMPLEMENTED;
3145 goto error;
3146 }
3147
3148 if (nb_chan > 0) {
3149 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3150 if (*channels == NULL) {
3151 ret = -LTTCOMM_FATAL;
3152 goto error;
3153 }
3154
3155 list_lttng_channels(domain, session, *channels);
3156 } else {
3157 *channels = NULL;
3158 }
3159
3160 return nb_chan;
3161
3162 error:
3163 return ret;
3164 }
3165
3166 /*
3167 * Command LTTNG_LIST_EVENTS processed by the client thread.
3168 */
3169 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3170 char *channel_name, struct lttng_event **events)
3171 {
3172 int ret = 0;
3173 ssize_t nb_event = 0;
3174
3175 switch (domain) {
3176 case LTTNG_DOMAIN_KERNEL:
3177 if (session->kernel_session != NULL) {
3178 nb_event = list_lttng_kernel_events(channel_name,
3179 session->kernel_session, events);
3180 }
3181 break;
3182 case LTTNG_DOMAIN_UST:
3183 {
3184 if (session->ust_session != NULL) {
3185 nb_event = list_lttng_ust_global_events(channel_name,
3186 &session->ust_session->domain_global, events);
3187 }
3188 break;
3189 }
3190 default:
3191 ret = -LTTCOMM_NOT_IMPLEMENTED;
3192 goto error;
3193 }
3194
3195 ret = nb_event;
3196
3197 error:
3198 return ret;
3199 }
3200
3201 /*
3202 * Process the command requested by the lttng client within the command
3203 * context structure. This function make sure that the return structure (llm)
3204 * is set and ready for transmission before returning.
3205 *
3206 * Return any error encountered or 0 for success.
3207 */
3208 static int process_client_msg(struct command_ctx *cmd_ctx)
3209 {
3210 int ret = LTTCOMM_OK;
3211 int need_tracing_session = 1;
3212
3213 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3214
3215 if (opt_no_kernel && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
3216 ret = LTTCOMM_KERN_NA;
3217 goto error;
3218 }
3219
3220 /*
3221 * Check for command that don't needs to allocate a returned payload. We do
3222 * this here so we don't have to make the call for no payload at each
3223 * command.
3224 */
3225 switch(cmd_ctx->lsm->cmd_type) {
3226 case LTTNG_LIST_SESSIONS:
3227 case LTTNG_LIST_TRACEPOINTS:
3228 case LTTNG_LIST_DOMAINS:
3229 case LTTNG_LIST_CHANNELS:
3230 case LTTNG_LIST_EVENTS:
3231 break;
3232 default:
3233 /* Setup lttng message with no payload */
3234 ret = setup_lttng_msg(cmd_ctx, 0);
3235 if (ret < 0) {
3236 /* This label does not try to unlock the session */
3237 goto init_setup_error;
3238 }
3239 }
3240
3241 /* Commands that DO NOT need a session. */
3242 switch (cmd_ctx->lsm->cmd_type) {
3243 case LTTNG_CALIBRATE:
3244 case LTTNG_CREATE_SESSION:
3245 case LTTNG_LIST_SESSIONS:
3246 case LTTNG_LIST_TRACEPOINTS:
3247 need_tracing_session = 0;
3248 break;
3249 default:
3250 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3251 session_lock_list();
3252 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3253 session_unlock_list();
3254 if (cmd_ctx->session == NULL) {
3255 if (cmd_ctx->lsm->session.name != NULL) {
3256 ret = LTTCOMM_SESS_NOT_FOUND;
3257 } else {
3258 /* If no session name specified */
3259 ret = LTTCOMM_SELECT_SESS;
3260 }
3261 goto error;
3262 } else {
3263 /* Acquire lock for the session */
3264 session_lock(cmd_ctx->session);
3265 }
3266 break;
3267 }
3268
3269 /*
3270 * Check domain type for specific "pre-action".
3271 */
3272 switch (cmd_ctx->lsm->domain.type) {
3273 case LTTNG_DOMAIN_KERNEL:
3274 if (!is_root) {
3275 ret = LTTCOMM_KERN_NA;
3276 goto error;
3277 }
3278
3279 /* Kernel tracer check */
3280 if (kernel_tracer_fd == 0) {
3281 /* Basically, load kernel tracer modules */
3282 init_kernel_tracer();
3283 if (kernel_tracer_fd == 0) {
3284 ret = LTTCOMM_KERN_NA;
3285 goto error;
3286 }
3287 }
3288
3289 /* Need a session for kernel command */
3290 if (need_tracing_session) {
3291 if (cmd_ctx->session->kernel_session == NULL) {
3292 ret = create_kernel_session(cmd_ctx->session);
3293 if (ret < 0) {
3294 ret = LTTCOMM_KERN_SESS_FAIL;
3295 goto error;
3296 }
3297 }
3298
3299 /* Start the kernel consumer daemon */
3300 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3301 if (kconsumer_data.pid == 0 &&
3302 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3303 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3304 ret = start_consumerd(&kconsumer_data);
3305 if (ret < 0) {
3306 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3307 goto error;
3308 }
3309 } else {
3310 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3311 }
3312 }
3313 break;
3314 case LTTNG_DOMAIN_UST:
3315 {
3316 if (need_tracing_session) {
3317 if (cmd_ctx->session->ust_session == NULL) {
3318 ret = create_ust_session(cmd_ctx->session,
3319 &cmd_ctx->lsm->domain);
3320 if (ret != LTTCOMM_OK) {
3321 goto error;
3322 }
3323 }
3324 /* Start the UST consumer daemons */
3325 /* 64-bit */
3326 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3327 if (consumerd64_bin[0] != '\0' &&
3328 ustconsumer64_data.pid == 0 &&
3329 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3330 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3331 ret = start_consumerd(&ustconsumer64_data);
3332 if (ret < 0) {
3333 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3334 ust_consumerd64_fd = -EINVAL;
3335 goto error;
3336 }
3337
3338 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3339 } else {
3340 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3341 }
3342 /* 32-bit */
3343 if (consumerd32_bin[0] != '\0' &&
3344 ustconsumer32_data.pid == 0 &&
3345 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3346 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3347 ret = start_consumerd(&ustconsumer32_data);
3348 if (ret < 0) {
3349 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3350 ust_consumerd32_fd = -EINVAL;
3351 goto error;
3352 }
3353 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3354 } else {
3355 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3356 }
3357 }
3358 break;
3359 }
3360 default:
3361 break;
3362 }
3363
3364 /*
3365 * Check that the UID or GID match that of the tracing session.
3366 * The root user can interact with all sessions.
3367 */
3368 if (need_tracing_session) {
3369 if (!session_access_ok(cmd_ctx->session,
3370 cmd_ctx->creds.uid, cmd_ctx->creds.gid)) {
3371 ret = LTTCOMM_EPERM;
3372 goto error;
3373 }
3374 }
3375
3376 /* Process by command type */
3377 switch (cmd_ctx->lsm->cmd_type) {
3378 case LTTNG_ADD_CONTEXT:
3379 {
3380 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3381 cmd_ctx->lsm->u.context.channel_name,
3382 cmd_ctx->lsm->u.context.event_name,
3383 &cmd_ctx->lsm->u.context.ctx);
3384 break;
3385 }
3386 case LTTNG_DISABLE_CHANNEL:
3387 {
3388 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3389 cmd_ctx->lsm->u.disable.channel_name);
3390 break;
3391 }
3392 case LTTNG_DISABLE_EVENT:
3393 {
3394 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3395 cmd_ctx->lsm->u.disable.channel_name,
3396 cmd_ctx->lsm->u.disable.name);
3397 ret = LTTCOMM_OK;
3398 break;
3399 }
3400 case LTTNG_DISABLE_ALL_EVENT:
3401 {
3402 DBG("Disabling all events");
3403
3404 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3405 cmd_ctx->lsm->u.disable.channel_name);
3406 break;
3407 }
3408 case LTTNG_ENABLE_CHANNEL:
3409 {
3410 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3411 &cmd_ctx->lsm->u.channel.chan);
3412 break;
3413 }
3414 case LTTNG_ENABLE_EVENT:
3415 {
3416 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3417 cmd_ctx->lsm->u.enable.channel_name,
3418 &cmd_ctx->lsm->u.enable.event);
3419 break;
3420 }
3421 case LTTNG_ENABLE_ALL_EVENT:
3422 {
3423 DBG("Enabling all events");
3424
3425 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3426 cmd_ctx->lsm->u.enable.channel_name,
3427 cmd_ctx->lsm->u.enable.event.type);
3428 break;
3429 }
3430 case LTTNG_LIST_TRACEPOINTS:
3431 {
3432 struct lttng_event *events;
3433 ssize_t nb_events;
3434
3435 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3436 if (nb_events < 0) {
3437 ret = -nb_events;
3438 goto error;
3439 }
3440
3441 /*
3442 * Setup lttng message with payload size set to the event list size in
3443 * bytes and then copy list into the llm payload.
3444 */
3445 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3446 if (ret < 0) {
3447 free(events);
3448 goto setup_error;
3449 }
3450
3451 /* Copy event list into message payload */
3452 memcpy(cmd_ctx->llm->payload, events,
3453 sizeof(struct lttng_event) * nb_events);
3454
3455 free(events);
3456
3457 ret = LTTCOMM_OK;
3458 break;
3459 }
3460 case LTTNG_START_TRACE:
3461 {
3462 ret = cmd_start_trace(cmd_ctx->session);
3463 break;
3464 }
3465 case LTTNG_STOP_TRACE:
3466 {
3467 ret = cmd_stop_trace(cmd_ctx->session);
3468 break;
3469 }
3470 case LTTNG_CREATE_SESSION:
3471 {
3472 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3473 cmd_ctx->lsm->session.path, &cmd_ctx->creds);
3474 break;
3475 }
3476 case LTTNG_DESTROY_SESSION:
3477 {
3478 ret = cmd_destroy_session(cmd_ctx->session,
3479 cmd_ctx->lsm->session.name);
3480 break;
3481 }
3482 case LTTNG_LIST_DOMAINS:
3483 {
3484 ssize_t nb_dom;
3485 struct lttng_domain *domains;
3486
3487 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3488 if (nb_dom < 0) {
3489 ret = -nb_dom;
3490 goto error;
3491 }
3492
3493 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3494 if (ret < 0) {
3495 goto setup_error;
3496 }
3497
3498 /* Copy event list into message payload */
3499 memcpy(cmd_ctx->llm->payload, domains,
3500 nb_dom * sizeof(struct lttng_domain));
3501
3502 free(domains);
3503
3504 ret = LTTCOMM_OK;
3505 break;
3506 }
3507 case LTTNG_LIST_CHANNELS:
3508 {
3509 size_t nb_chan;
3510 struct lttng_channel *channels;
3511
3512 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
3513 cmd_ctx->session, &channels);
3514 if (nb_chan < 0) {
3515 ret = -nb_chan;
3516 goto error;
3517 }
3518
3519 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3520 if (ret < 0) {
3521 goto setup_error;
3522 }
3523
3524 /* Copy event list into message payload */
3525 memcpy(cmd_ctx->llm->payload, channels,
3526 nb_chan * sizeof(struct lttng_channel));
3527
3528 free(channels);
3529
3530 ret = LTTCOMM_OK;
3531 break;
3532 }
3533 case LTTNG_LIST_EVENTS:
3534 {
3535 ssize_t nb_event;
3536 struct lttng_event *events = NULL;
3537
3538 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
3539 cmd_ctx->lsm->u.list.channel_name, &events);
3540 if (nb_event < 0) {
3541 ret = -nb_event;
3542 goto error;
3543 }
3544
3545 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3546 if (ret < 0) {
3547 goto setup_error;
3548 }
3549
3550 /* Copy event list into message payload */
3551 memcpy(cmd_ctx->llm->payload, events,
3552 nb_event * sizeof(struct lttng_event));
3553
3554 free(events);
3555
3556 ret = LTTCOMM_OK;
3557 break;
3558 }
3559 case LTTNG_LIST_SESSIONS:
3560 {
3561 unsigned int nr_sessions;
3562
3563 session_lock_list();
3564 nr_sessions = lttng_sessions_count(cmd_ctx->creds.uid, cmd_ctx->creds.gid);
3565 if (nr_sessions == 0) {
3566 ret = LTTCOMM_NO_SESSION;
3567 session_unlock_list();
3568 goto error;
3569 }
3570 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * nr_sessions);
3571 if (ret < 0) {
3572 session_unlock_list();
3573 goto setup_error;
3574 }
3575
3576 /* Filled the session array */
3577 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload),
3578 cmd_ctx->creds.uid, cmd_ctx->creds.gid);
3579
3580 session_unlock_list();
3581
3582 ret = LTTCOMM_OK;
3583 break;
3584 }
3585 case LTTNG_CALIBRATE:
3586 {
3587 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3588 &cmd_ctx->lsm->u.calibrate);
3589 break;
3590 }
3591 case LTTNG_REGISTER_CONSUMER:
3592 {
3593 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3594 cmd_ctx->lsm->u.reg.path);
3595 break;
3596 }
3597 default:
3598 ret = LTTCOMM_UND;
3599 break;
3600 }
3601
3602 error:
3603 if (cmd_ctx->llm == NULL) {
3604 DBG("Missing llm structure. Allocating one.");
3605 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3606 goto setup_error;
3607 }
3608 }
3609 /* Set return code */
3610 cmd_ctx->llm->ret_code = ret;
3611 setup_error:
3612 if (cmd_ctx->session) {
3613 session_unlock(cmd_ctx->session);
3614 }
3615 init_setup_error:
3616 return ret;
3617 }
3618
3619 /*
3620 * This thread manage all clients request using the unix client socket for
3621 * communication.
3622 */
3623 static void *thread_manage_clients(void *data)
3624 {
3625 int sock = 0, ret, i, pollfd;
3626 uint32_t revents, nb_fd;
3627 struct command_ctx *cmd_ctx = NULL;
3628 struct lttng_poll_event events;
3629
3630 DBG("[thread] Manage client started");
3631
3632 rcu_register_thread();
3633
3634 ret = lttcomm_listen_unix_sock(client_sock);
3635 if (ret < 0) {
3636 goto error;
3637 }
3638
3639 /*
3640 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3641 * more will be added to this poll set.
3642 */
3643 ret = create_thread_poll_set(&events, 2);
3644 if (ret < 0) {
3645 goto error;
3646 }
3647
3648 /* Add the application registration socket */
3649 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3650 if (ret < 0) {
3651 goto error;
3652 }
3653
3654 /*
3655 * Notify parent pid that we are ready to accept command for client side.
3656 */
3657 if (opt_sig_parent) {
3658 kill(ppid, SIGCHLD);
3659 }
3660
3661 while (1) {
3662 DBG("Accepting client command ...");
3663
3664 nb_fd = LTTNG_POLL_GETNB(&events);
3665
3666 /* Inifinite blocking call, waiting for transmission */
3667 ret = lttng_poll_wait(&events, -1);
3668 if (ret < 0) {
3669 goto error;
3670 }
3671
3672 for (i = 0; i < nb_fd; i++) {
3673 /* Fetch once the poll data */
3674 revents = LTTNG_POLL_GETEV(&events, i);
3675 pollfd = LTTNG_POLL_GETFD(&events, i);
3676
3677 /* Thread quit pipe has been closed. Killing thread. */
3678 ret = check_thread_quit_pipe(pollfd, revents);
3679 if (ret) {
3680 goto error;
3681 }
3682
3683 /* Event on the registration socket */
3684 if (pollfd == client_sock) {
3685 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3686 ERR("Client socket poll error");
3687 goto error;
3688 }
3689 }
3690 }
3691
3692 DBG("Wait for client response");
3693
3694 sock = lttcomm_accept_unix_sock(client_sock);
3695 if (sock < 0) {
3696 goto error;
3697 }
3698
3699 /* Set socket option for credentials retrieval */
3700 ret = lttcomm_setsockopt_creds_unix_sock(sock);
3701 if (ret < 0) {
3702 goto error;
3703 }
3704
3705 /* Allocate context command to process the client request */
3706 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3707 if (cmd_ctx == NULL) {
3708 perror("zmalloc cmd_ctx");
3709 goto error;
3710 }
3711
3712 /* Allocate data buffer for reception */
3713 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3714 if (cmd_ctx->lsm == NULL) {
3715 perror("zmalloc cmd_ctx->lsm");
3716 goto error;
3717 }
3718
3719 cmd_ctx->llm = NULL;
3720 cmd_ctx->session = NULL;
3721
3722 /*
3723 * Data is received from the lttng client. The struct
3724 * lttcomm_session_msg (lsm) contains the command and data request of
3725 * the client.
3726 */
3727 DBG("Receiving data from client ...");
3728 ret = lttcomm_recv_creds_unix_sock(sock, cmd_ctx->lsm,
3729 sizeof(struct lttcomm_session_msg), &cmd_ctx->creds);
3730 if (ret <= 0) {
3731 DBG("Nothing recv() from client... continuing");
3732 close(sock);
3733 free(cmd_ctx);
3734 continue;
3735 }
3736
3737 // TODO: Validate cmd_ctx including sanity check for
3738 // security purpose.
3739
3740 rcu_thread_online();
3741 /*
3742 * This function dispatch the work to the kernel or userspace tracer
3743 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3744 * informations for the client. The command context struct contains
3745 * everything this function may needs.
3746 */
3747 ret = process_client_msg(cmd_ctx);
3748 rcu_thread_offline();
3749 if (ret < 0) {
3750 /*
3751 * TODO: Inform client somehow of the fatal error. At
3752 * this point, ret < 0 means that a zmalloc failed
3753 * (ENOMEM). Error detected but still accept command.
3754 */
3755 clean_command_ctx(&cmd_ctx);
3756 continue;
3757 }
3758
3759 DBG("Sending response (size: %d, retcode: %s)",
3760 cmd_ctx->lttng_msg_size,
3761 lttng_strerror(-cmd_ctx->llm->ret_code));
3762 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3763 if (ret < 0) {
3764 ERR("Failed to send data back to client");
3765 }
3766
3767 /* End of transmission */
3768 close(sock);
3769
3770 clean_command_ctx(&cmd_ctx);
3771 }
3772
3773 error:
3774 DBG("Client thread dying");
3775 unlink(client_unix_sock_path);
3776 close(client_sock);
3777 close(sock);
3778
3779 lttng_poll_clean(&events);
3780 clean_command_ctx(&cmd_ctx);
3781
3782 rcu_unregister_thread();
3783 return NULL;
3784 }
3785
3786
3787 /*
3788 * usage function on stderr
3789 */
3790 static void usage(void)
3791 {
3792 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3793 fprintf(stderr, " -h, --help Display this usage.\n");
3794 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3795 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3796 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3797 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3798 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
3799 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
3800 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
3801 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
3802 fprintf(stderr, " --consumerd32-path PATH Specify path for the 32-bit UST consumer daemon binary\n");
3803 fprintf(stderr, " --consumerd32-libdir PATH Specify path for the 32-bit UST consumer daemon libraries\n");
3804 fprintf(stderr, " --consumerd64-path PATH Specify path for the 64-bit UST consumer daemon binary\n");
3805 fprintf(stderr, " --consumerd64-libdir PATH Specify path for the 64-bit UST consumer daemon libraries\n");
3806 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3807 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3808 fprintf(stderr, " -V, --version Show version number.\n");
3809 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3810 fprintf(stderr, " -q, --quiet No output at all.\n");
3811 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3812 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3813 fprintf(stderr, " --no-kernel Disable kernel tracer\n");
3814 }
3815
3816 /*
3817 * daemon argument parsing
3818 */
3819 static int parse_args(int argc, char **argv)
3820 {
3821 int c;
3822
3823 static struct option long_options[] = {
3824 { "client-sock", 1, 0, 'c' },
3825 { "apps-sock", 1, 0, 'a' },
3826 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3827 { "kconsumerd-err-sock", 1, 0, 'E' },
3828 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
3829 { "ustconsumerd32-err-sock", 1, 0, 'H' },
3830 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
3831 { "ustconsumerd64-err-sock", 1, 0, 'F' },
3832 { "consumerd32-path", 1, 0, 'u' },
3833 { "consumerd32-libdir", 1, 0, 'U' },
3834 { "consumerd64-path", 1, 0, 't' },
3835 { "consumerd64-libdir", 1, 0, 'T' },
3836 { "daemonize", 0, 0, 'd' },
3837 { "sig-parent", 0, 0, 'S' },
3838 { "help", 0, 0, 'h' },
3839 { "group", 1, 0, 'g' },
3840 { "version", 0, 0, 'V' },
3841 { "quiet", 0, 0, 'q' },
3842 { "verbose", 0, 0, 'v' },
3843 { "verbose-consumer", 0, 0, 'Z' },
3844 { "no-kernel", 0, 0, 'N' },
3845 { NULL, 0, 0, 0 }
3846 };
3847
3848 while (1) {
3849 int option_index = 0;
3850 c = getopt_long(argc, argv, "dhqvVSN" "a:c:g:s:C:E:D:F:Z:u:t",
3851 long_options, &option_index);
3852 if (c == -1) {
3853 break;
3854 }
3855
3856 switch (c) {
3857 case 0:
3858 fprintf(stderr, "option %s", long_options[option_index].name);
3859 if (optarg) {
3860 fprintf(stderr, " with arg %s\n", optarg);
3861 }
3862 break;
3863 case 'c':
3864 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3865 break;
3866 case 'a':
3867 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3868 break;
3869 case 'd':
3870 opt_daemon = 1;
3871 break;
3872 case 'g':
3873 opt_tracing_group = optarg;
3874 break;
3875 case 'h':
3876 usage();
3877 exit(EXIT_FAILURE);
3878 case 'V':
3879 fprintf(stdout, "%s\n", VERSION);
3880 exit(EXIT_SUCCESS);
3881 case 'S':
3882 opt_sig_parent = 1;
3883 break;
3884 case 'E':
3885 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3886 break;
3887 case 'C':
3888 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3889 break;
3890 case 'F':
3891 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3892 break;
3893 case 'D':
3894 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3895 break;
3896 case 'H':
3897 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3898 break;
3899 case 'G':
3900 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3901 break;
3902 case 'N':
3903 opt_no_kernel = 1;
3904 break;
3905 case 'q':
3906 opt_quiet = 1;
3907 break;
3908 case 'v':
3909 /* Verbose level can increase using multiple -v */
3910 opt_verbose += 1;
3911 break;
3912 case 'Z':
3913 opt_verbose_consumer += 1;
3914 break;
3915 case 'u':
3916 consumerd32_bin= optarg;
3917 break;
3918 case 'U':
3919 consumerd32_libdir = optarg;
3920 break;
3921 case 't':
3922 consumerd64_bin = optarg;
3923 break;
3924 case 'T':
3925 consumerd64_libdir = optarg;
3926 break;
3927 default:
3928 /* Unknown option or other error.
3929 * Error is printed by getopt, just return */
3930 return -1;
3931 }
3932 }
3933
3934 return 0;
3935 }
3936
3937 /*
3938 * Creates the two needed socket by the daemon.
3939 * apps_sock - The communication socket for all UST apps.
3940 * client_sock - The communication of the cli tool (lttng).
3941 */
3942 static int init_daemon_socket(void)
3943 {
3944 int ret = 0;
3945 mode_t old_umask;
3946
3947 old_umask = umask(0);
3948
3949 /* Create client tool unix socket */
3950 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3951 if (client_sock < 0) {
3952 ERR("Create unix sock failed: %s", client_unix_sock_path);
3953 ret = -1;
3954 goto end;
3955 }
3956
3957 /* File permission MUST be 660 */
3958 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3959 if (ret < 0) {
3960 ERR("Set file permissions failed: %s", client_unix_sock_path);
3961 perror("chmod");
3962 goto end;
3963 }
3964
3965 /* Create the application unix socket */
3966 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3967 if (apps_sock < 0) {
3968 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3969 ret = -1;
3970 goto end;
3971 }
3972
3973 /* File permission MUST be 666 */
3974 ret = chmod(apps_unix_sock_path,
3975 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3976 if (ret < 0) {
3977 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3978 perror("chmod");
3979 goto end;
3980 }
3981
3982 end:
3983 umask(old_umask);
3984 return ret;
3985 }
3986
3987 /*
3988 * Check if the global socket is available, and if a daemon is answering at the
3989 * other side. If yes, error is returned.
3990 */
3991 static int check_existing_daemon(void)
3992 {
3993 if (access(client_unix_sock_path, F_OK) < 0 &&
3994 access(apps_unix_sock_path, F_OK) < 0) {
3995 return 0;
3996 }
3997
3998 /* Is there anybody out there ? */
3999 if (lttng_session_daemon_alive()) {
4000 return -EEXIST;
4001 } else {
4002 return 0;
4003 }
4004 }
4005
4006 /*
4007 * Set the tracing group gid onto the client socket.
4008 *
4009 * Race window between mkdir and chown is OK because we are going from more
4010 * permissive (root.root) to les permissive (root.tracing).
4011 */
4012 static int set_permissions(char *rundir)
4013 {
4014 int ret;
4015 gid_t gid;
4016
4017 gid = allowed_group();
4018 if (gid < 0) {
4019 WARN("No tracing group detected");
4020 ret = 0;
4021 goto end;
4022 }
4023
4024 /* Set lttng run dir */
4025 ret = chown(rundir, 0, gid);
4026 if (ret < 0) {
4027 ERR("Unable to set group on %s", rundir);
4028 perror("chown");
4029 }
4030
4031 /* lttng client socket path */
4032 ret = chown(client_unix_sock_path, 0, gid);
4033 if (ret < 0) {
4034 ERR("Unable to set group on %s", client_unix_sock_path);
4035 perror("chown");
4036 }
4037
4038 /* kconsumer error socket path */
4039 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
4040 if (ret < 0) {
4041 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
4042 perror("chown");
4043 }
4044
4045 /* 64-bit ustconsumer error socket path */
4046 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
4047 if (ret < 0) {
4048 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
4049 perror("chown");
4050 }
4051
4052 /* 32-bit ustconsumer compat32 error socket path */
4053 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
4054 if (ret < 0) {
4055 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
4056 perror("chown");
4057 }
4058
4059 DBG("All permissions are set");
4060
4061 end:
4062 return ret;
4063 }
4064
4065 /*
4066 * Create the pipe used to wake up the kernel thread.
4067 */
4068 static int create_kernel_poll_pipe(void)
4069 {
4070 return pipe2(kernel_poll_pipe, O_CLOEXEC);
4071 }
4072
4073 /*
4074 * Create the application command pipe to wake thread_manage_apps.
4075 */
4076 static int create_apps_cmd_pipe(void)
4077 {
4078 return pipe2(apps_cmd_pipe, O_CLOEXEC);
4079 }
4080
4081 /*
4082 * Create the lttng run directory needed for all global sockets and pipe.
4083 */
4084 static int create_lttng_rundir(const char *rundir)
4085 {
4086 int ret;
4087
4088 DBG3("Creating LTTng run directory: %s", rundir);
4089
4090 ret = mkdir(rundir, S_IRWXU | S_IRWXG );
4091 if (ret < 0) {
4092 if (errno != EEXIST) {
4093 ERR("Unable to create %s", rundir);
4094 goto error;
4095 } else {
4096 ret = 0;
4097 }
4098 }
4099
4100 error:
4101 return ret;
4102 }
4103
4104 /*
4105 * Setup sockets and directory needed by the kconsumerd communication with the
4106 * session daemon.
4107 */
4108 static int set_consumer_sockets(struct consumer_data *consumer_data,
4109 const char *rundir)
4110 {
4111 int ret;
4112 char path[PATH_MAX];
4113
4114 switch (consumer_data->type) {
4115 case LTTNG_CONSUMER_KERNEL:
4116 snprintf(path, PATH_MAX, KCONSUMERD_PATH, rundir);
4117 break;
4118 case LTTNG_CONSUMER64_UST:
4119 snprintf(path, PATH_MAX, USTCONSUMERD64_PATH, rundir);
4120 break;
4121 case LTTNG_CONSUMER32_UST:
4122 snprintf(path, PATH_MAX, USTCONSUMERD32_PATH, rundir);
4123 break;
4124 default:
4125 ERR("Consumer type unknown");
4126 ret = -EINVAL;
4127 goto error;
4128 }
4129
4130 DBG2("Creating consumer directory: %s", path);
4131
4132 ret = mkdir(path, S_IRWXU | S_IRWXG);
4133 if (ret < 0) {
4134 if (errno != EEXIST) {
4135 ERR("Failed to create %s", path);
4136 goto error;
4137 }
4138 ret = 0;
4139 }
4140
4141 /* Create the kconsumerd error unix socket */
4142 consumer_data->err_sock =
4143 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
4144 if (consumer_data->err_sock < 0) {
4145 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
4146 ret = -1;
4147 goto error;
4148 }
4149
4150 /* File permission MUST be 660 */
4151 ret = chmod(consumer_data->err_unix_sock_path,
4152 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
4153 if (ret < 0) {
4154 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
4155 PERROR("chmod");
4156 goto error;
4157 }
4158
4159 error:
4160 return ret;
4161 }
4162
4163 /*
4164 * Signal handler for the daemon
4165 *
4166 * Simply stop all worker threads, leaving main() return gracefully after
4167 * joining all threads and calling cleanup().
4168 */
4169 static void sighandler(int sig)
4170 {
4171 switch (sig) {
4172 case SIGPIPE:
4173 DBG("SIGPIPE caugth");
4174 return;
4175 case SIGINT:
4176 DBG("SIGINT caugth");
4177 stop_threads();
4178 break;
4179 case SIGTERM:
4180 DBG("SIGTERM caugth");
4181 stop_threads();
4182 break;
4183 default:
4184 break;
4185 }
4186 }
4187
4188 /*
4189 * Setup signal handler for :
4190 * SIGINT, SIGTERM, SIGPIPE
4191 */
4192 static int set_signal_handler(void)
4193 {
4194 int ret = 0;
4195 struct sigaction sa;
4196 sigset_t sigset;
4197
4198 if ((ret = sigemptyset(&sigset)) < 0) {
4199 perror("sigemptyset");
4200 return ret;
4201 }
4202
4203 sa.sa_handler = sighandler;
4204 sa.sa_mask = sigset;
4205 sa.sa_flags = 0;
4206 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
4207 perror("sigaction");
4208 return ret;
4209 }
4210
4211 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
4212 perror("sigaction");
4213 return ret;
4214 }
4215
4216 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
4217 perror("sigaction");
4218 return ret;
4219 }
4220
4221 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
4222
4223 return ret;
4224 }
4225
4226 /*
4227 * Set open files limit to unlimited. This daemon can open a large number of
4228 * file descriptors in order to consumer multiple kernel traces.
4229 */
4230 static void set_ulimit(void)
4231 {
4232 int ret;
4233 struct rlimit lim;
4234
4235 /* The kernel does not allowed an infinite limit for open files */
4236 lim.rlim_cur = 65535;
4237 lim.rlim_max = 65535;
4238
4239 ret = setrlimit(RLIMIT_NOFILE, &lim);
4240 if (ret < 0) {
4241 perror("failed to set open files limit");
4242 }
4243 }
4244
4245 /*
4246 * main
4247 */
4248 int main(int argc, char **argv)
4249 {
4250 int ret = 0;
4251 void *status;
4252 const char *home_path;
4253
4254 rcu_register_thread();
4255
4256 /* Create thread quit pipe */
4257 if ((ret = init_thread_quit_pipe()) < 0) {
4258 goto error;
4259 }
4260
4261 setup_consumerd_path();
4262
4263 /* Parse arguments */
4264 progname = argv[0];
4265 if ((ret = parse_args(argc, argv) < 0)) {
4266 goto error;
4267 }
4268
4269 /* Daemonize */
4270 if (opt_daemon) {
4271 ret = daemon(0, 0);
4272 if (ret < 0) {
4273 perror("daemon");
4274 goto error;
4275 }
4276 }
4277
4278 /* Check if daemon is UID = 0 */
4279 is_root = !getuid();
4280
4281 if (is_root) {
4282 rundir = strdup(DEFAULT_LTTNG_RUNDIR);
4283
4284 /* Create global run dir with root access */
4285 ret = create_lttng_rundir(rundir);
4286 if (ret < 0) {
4287 goto error;
4288 }
4289
4290 if (strlen(apps_unix_sock_path) == 0) {
4291 snprintf(apps_unix_sock_path, PATH_MAX,
4292 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
4293 }
4294
4295 if (strlen(client_unix_sock_path) == 0) {
4296 snprintf(client_unix_sock_path, PATH_MAX,
4297 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
4298 }
4299
4300 /* Set global SHM for ust */
4301 if (strlen(wait_shm_path) == 0) {
4302 snprintf(wait_shm_path, PATH_MAX,
4303 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
4304 }
4305
4306 /* Setup kernel consumerd path */
4307 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX,
4308 KCONSUMERD_ERR_SOCK_PATH, rundir);
4309 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX,
4310 KCONSUMERD_CMD_SOCK_PATH, rundir);
4311
4312 DBG2("Kernel consumer err path: %s",
4313 kconsumer_data.err_unix_sock_path);
4314 DBG2("Kernel consumer cmd path: %s",
4315 kconsumer_data.cmd_unix_sock_path);
4316 } else {
4317 home_path = get_home_dir();
4318 if (home_path == NULL) {
4319 /* TODO: Add --socket PATH option */
4320 ERR("Can't get HOME directory for sockets creation.");
4321 ret = -EPERM;
4322 goto error;
4323 }
4324
4325 /*
4326 * Create rundir from home path. This will create something like
4327 * $HOME/.lttng
4328 */
4329 ret = asprintf(&rundir, DEFAULT_LTTNG_HOME_RUNDIR, home_path);
4330 if (ret < 0) {
4331 ret = -ENOMEM;
4332 goto error;
4333 }
4334
4335 ret = create_lttng_rundir(rundir);
4336 if (ret < 0) {
4337 goto error;
4338 }
4339
4340 if (strlen(apps_unix_sock_path) == 0) {
4341 snprintf(apps_unix_sock_path, PATH_MAX,
4342 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
4343 }
4344
4345 /* Set the cli tool unix socket path */
4346 if (strlen(client_unix_sock_path) == 0) {
4347 snprintf(client_unix_sock_path, PATH_MAX,
4348 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
4349 }
4350
4351 /* Set global SHM for ust */
4352 if (strlen(wait_shm_path) == 0) {
4353 snprintf(wait_shm_path, PATH_MAX,
4354 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
4355 }
4356 }
4357
4358 DBG("Client socket path %s", client_unix_sock_path);
4359 DBG("Application socket path %s", apps_unix_sock_path);
4360 DBG("LTTng run directory path: %s", rundir);
4361
4362 /* 32 bits consumerd path setup */
4363 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX,
4364 USTCONSUMERD32_ERR_SOCK_PATH, rundir);
4365 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX,
4366 USTCONSUMERD32_CMD_SOCK_PATH, rundir);
4367
4368 DBG2("UST consumer 32 bits err path: %s",
4369 ustconsumer32_data.err_unix_sock_path);
4370 DBG2("UST consumer 32 bits cmd path: %s",
4371 ustconsumer32_data.cmd_unix_sock_path);
4372
4373 /* 64 bits consumerd path setup */
4374 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX,
4375 USTCONSUMERD64_ERR_SOCK_PATH, rundir);
4376 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX,
4377 USTCONSUMERD64_CMD_SOCK_PATH, rundir);
4378
4379 DBG2("UST consumer 64 bits err path: %s",
4380 ustconsumer64_data.err_unix_sock_path);
4381 DBG2("UST consumer 64 bits cmd path: %s",
4382 ustconsumer64_data.cmd_unix_sock_path);
4383
4384 /*
4385 * See if daemon already exist.
4386 */
4387 if ((ret = check_existing_daemon()) < 0) {
4388 ERR("Already running daemon.\n");
4389 /*
4390 * We do not goto exit because we must not cleanup()
4391 * because a daemon is already running.
4392 */
4393 goto error;
4394 }
4395
4396 /* After this point, we can safely call cleanup() with "goto exit" */
4397
4398 /*
4399 * These actions must be executed as root. We do that *after* setting up
4400 * the sockets path because we MUST make the check for another daemon using
4401 * those paths *before* trying to set the kernel consumer sockets and init
4402 * kernel tracer.
4403 */
4404 if (is_root) {
4405 ret = set_consumer_sockets(&kconsumer_data, rundir);
4406 if (ret < 0) {
4407 goto exit;
4408 }
4409
4410 /* Setup kernel tracer */
4411 if (!opt_no_kernel) {
4412 init_kernel_tracer();
4413 }
4414
4415 /* Set ulimit for open files */
4416 set_ulimit();
4417 }
4418
4419 ret = set_consumer_sockets(&ustconsumer64_data, rundir);
4420 if (ret < 0) {
4421 goto exit;
4422 }
4423
4424 ret = set_consumer_sockets(&ustconsumer32_data, rundir);
4425 if (ret < 0) {
4426 goto exit;
4427 }
4428
4429 if ((ret = set_signal_handler()) < 0) {
4430 goto exit;
4431 }
4432
4433 /* Setup the needed unix socket */
4434 if ((ret = init_daemon_socket()) < 0) {
4435 goto exit;
4436 }
4437
4438 /* Set credentials to socket */
4439 if (is_root && ((ret = set_permissions(rundir)) < 0)) {
4440 goto exit;
4441 }
4442
4443 /* Get parent pid if -S, --sig-parent is specified. */
4444 if (opt_sig_parent) {
4445 ppid = getppid();
4446 }
4447
4448 /* Setup the kernel pipe for waking up the kernel thread */
4449 if ((ret = create_kernel_poll_pipe()) < 0) {
4450 goto exit;
4451 }
4452
4453 /* Setup the thread apps communication pipe. */
4454 if ((ret = create_apps_cmd_pipe()) < 0) {
4455 goto exit;
4456 }
4457
4458 /* Init UST command queue. */
4459 cds_wfq_init(&ust_cmd_queue.queue);
4460
4461 /* Init UST app hash table */
4462 ust_app_ht_alloc();
4463
4464 /*
4465 * Get session list pointer. This pointer MUST NOT be free(). This list is
4466 * statically declared in session.c
4467 */
4468 session_list_ptr = session_get_list();
4469
4470 /* Set up max poll set size */
4471 lttng_poll_set_max_size();
4472
4473 /* Create thread to manage the client socket */
4474 ret = pthread_create(&client_thread, NULL,
4475 thread_manage_clients, (void *) NULL);
4476 if (ret != 0) {
4477 perror("pthread_create clients");
4478 goto exit_client;
4479 }
4480
4481 /* Create thread to dispatch registration */
4482 ret = pthread_create(&dispatch_thread, NULL,
4483 thread_dispatch_ust_registration, (void *) NULL);
4484 if (ret != 0) {
4485 perror("pthread_create dispatch");
4486 goto exit_dispatch;
4487 }
4488
4489 /* Create thread to manage application registration. */
4490 ret = pthread_create(&reg_apps_thread, NULL,
4491 thread_registration_apps, (void *) NULL);
4492 if (ret != 0) {
4493 perror("pthread_create registration");
4494 goto exit_reg_apps;
4495 }
4496
4497 /* Create thread to manage application socket */
4498 ret = pthread_create(&apps_thread, NULL,
4499 thread_manage_apps, (void *) NULL);
4500 if (ret != 0) {
4501 perror("pthread_create apps");
4502 goto exit_apps;
4503 }
4504
4505 /* Create kernel thread to manage kernel event */
4506 ret = pthread_create(&kernel_thread, NULL,
4507 thread_manage_kernel, (void *) NULL);
4508 if (ret != 0) {
4509 perror("pthread_create kernel");
4510 goto exit_kernel;
4511 }
4512
4513 ret = pthread_join(kernel_thread, &status);
4514 if (ret != 0) {
4515 perror("pthread_join");
4516 goto error; /* join error, exit without cleanup */
4517 }
4518
4519 exit_kernel:
4520 ret = pthread_join(apps_thread, &status);
4521 if (ret != 0) {
4522 perror("pthread_join");
4523 goto error; /* join error, exit without cleanup */
4524 }
4525
4526 exit_apps:
4527 ret = pthread_join(reg_apps_thread, &status);
4528 if (ret != 0) {
4529 perror("pthread_join");
4530 goto error; /* join error, exit without cleanup */
4531 }
4532
4533 exit_reg_apps:
4534 ret = pthread_join(dispatch_thread, &status);
4535 if (ret != 0) {
4536 perror("pthread_join");
4537 goto error; /* join error, exit without cleanup */
4538 }
4539
4540 exit_dispatch:
4541 ret = pthread_join(client_thread, &status);
4542 if (ret != 0) {
4543 perror("pthread_join");
4544 goto error; /* join error, exit without cleanup */
4545 }
4546
4547 ret = join_consumer_thread(&kconsumer_data);
4548 if (ret != 0) {
4549 perror("join_consumer");
4550 goto error; /* join error, exit without cleanup */
4551 }
4552
4553 exit_client:
4554 exit:
4555 /*
4556 * cleanup() is called when no other thread is running.
4557 */
4558 rcu_thread_online();
4559 cleanup();
4560 rcu_thread_offline();
4561 rcu_unregister_thread();
4562 if (!ret) {
4563 exit(EXIT_SUCCESS);
4564 }
4565 error:
4566 exit(EXIT_FAILURE);
4567 }
LTTng 2.0 tools and control repository
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