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New sessiond comm error for kernel version
[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 <common/common.h>
42 #include <common/compat/poll.h>
43 #include <common/defaults.h>
44 #include <common/kernel-consumer/kernel-consumer.h>
45 #include <common/ust-consumer/ust-consumer.h>
46
47 #include "lttng-sessiond.h"
48 #include "channel.h"
49 #include "context.h"
50 #include "event.h"
51 #include "futex.h"
52 #include "kernel.h"
53 #include "shm.h"
54 #include "ust-ctl.h"
55 #include "utils.h"
56
57 #define CONSUMERD_FILE "lttng-consumerd"
58
59 struct consumer_data {
60 enum lttng_consumer_type type;
61
62 pthread_t thread; /* Worker thread interacting with the consumer */
63 sem_t sem;
64
65 /* Mutex to control consumerd pid assignation */
66 pthread_mutex_t pid_mutex;
67 pid_t pid;
68
69 int err_sock;
70 int cmd_sock;
71
72 /* consumer error and command Unix socket path */
73 char err_unix_sock_path[PATH_MAX];
74 char cmd_unix_sock_path[PATH_MAX];
75 };
76
77 /* Const values */
78 const char default_home_dir[] = DEFAULT_HOME_DIR;
79 const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
80 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
81 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
82
83 /* Variables */
84 int opt_verbose; /* Not static for lttngerr.h */
85 int opt_verbose_consumer; /* Not static for lttngerr.h */
86 int opt_quiet; /* Not static for lttngerr.h */
87
88 const char *progname;
89 const char *opt_tracing_group;
90 static int opt_sig_parent;
91 static int opt_daemon;
92 static int opt_no_kernel;
93 static int is_root; /* Set to 1 if the daemon is running as root */
94 static pid_t ppid; /* Parent PID for --sig-parent option */
95 static char *rundir;
96
97 /* Consumer daemon specific control data */
98 static struct consumer_data kconsumer_data = {
99 .type = LTTNG_CONSUMER_KERNEL,
100 .err_unix_sock_path = DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
101 .cmd_unix_sock_path = DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
102 };
103 static struct consumer_data ustconsumer64_data = {
104 .type = LTTNG_CONSUMER64_UST,
105 .err_unix_sock_path = DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
106 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
107 };
108 static struct consumer_data ustconsumer32_data = {
109 .type = LTTNG_CONSUMER32_UST,
110 .err_unix_sock_path = DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
111 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
112 };
113
114 static int dispatch_thread_exit;
115
116 /* Global application Unix socket path */
117 static char apps_unix_sock_path[PATH_MAX];
118 /* Global client Unix socket path */
119 static char client_unix_sock_path[PATH_MAX];
120 /* global wait shm path for UST */
121 static char wait_shm_path[PATH_MAX];
122
123 /* Sockets and FDs */
124 static int client_sock;
125 static int apps_sock;
126 static int kernel_tracer_fd;
127 static int kernel_poll_pipe[2];
128
129 /*
130 * Quit pipe for all threads. This permits a single cancellation point
131 * for all threads when receiving an event on the pipe.
132 */
133 static int thread_quit_pipe[2];
134
135 /*
136 * This pipe is used to inform the thread managing application communication
137 * that a command is queued and ready to be processed.
138 */
139 static int apps_cmd_pipe[2];
140
141 /* Pthread, Mutexes and Semaphores */
142 static pthread_t apps_thread;
143 static pthread_t reg_apps_thread;
144 static pthread_t client_thread;
145 static pthread_t kernel_thread;
146 static pthread_t dispatch_thread;
147
148
149 /*
150 * UST registration command queue. This queue is tied with a futex and uses a N
151 * wakers / 1 waiter implemented and detailed in futex.c/.h
152 *
153 * The thread_manage_apps and thread_dispatch_ust_registration interact with
154 * this queue and the wait/wake scheme.
155 */
156 static struct ust_cmd_queue ust_cmd_queue;
157
158 /*
159 * Pointer initialized before thread creation.
160 *
161 * This points to the tracing session list containing the session count and a
162 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
163 * MUST NOT be taken if you call a public function in session.c.
164 *
165 * The lock is nested inside the structure: session_list_ptr->lock. Please use
166 * session_lock_list and session_unlock_list for lock acquisition.
167 */
168 static struct ltt_session_list *session_list_ptr;
169
170 int ust_consumerd64_fd = -1;
171 int ust_consumerd32_fd = -1;
172
173 static const char *consumerd32_bin = CONFIG_CONSUMERD32_BIN;
174 static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
175 static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
176 static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
177
178 static
179 void setup_consumerd_path(void)
180 {
181 const char *bin, *libdir;
182
183 /*
184 * Allow INSTALL_BIN_PATH to be used as a target path for the
185 * native architecture size consumer if CONFIG_CONSUMER*_PATH
186 * has not been defined.
187 */
188 #if (CAA_BITS_PER_LONG == 32)
189 if (!consumerd32_bin[0]) {
190 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
191 }
192 if (!consumerd32_libdir[0]) {
193 consumerd32_libdir = INSTALL_LIB_PATH;
194 }
195 #elif (CAA_BITS_PER_LONG == 64)
196 if (!consumerd64_bin[0]) {
197 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
198 }
199 if (!consumerd64_libdir[0]) {
200 consumerd64_libdir = INSTALL_LIB_PATH;
201 }
202 #else
203 #error "Unknown bitness"
204 #endif
205
206 /*
207 * runtime env. var. overrides the build default.
208 */
209 bin = getenv("LTTNG_CONSUMERD32_BIN");
210 if (bin) {
211 consumerd32_bin = bin;
212 }
213 bin = getenv("LTTNG_CONSUMERD64_BIN");
214 if (bin) {
215 consumerd64_bin = bin;
216 }
217 libdir = getenv("LTTNG_TOOLS_CONSUMERD32_LIBDIR");
218 if (libdir) {
219 consumerd32_libdir = libdir;
220 }
221 libdir = getenv("LTTNG_TOOLS_CONSUMERD64_LIBDIR");
222 if (libdir) {
223 consumerd64_libdir = libdir;
224 }
225 }
226
227 /*
228 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
229 */
230 static int create_thread_poll_set(struct lttng_poll_event *events,
231 unsigned int size)
232 {
233 int ret;
234
235 if (events == NULL || size == 0) {
236 ret = -1;
237 goto error;
238 }
239
240 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
241 if (ret < 0) {
242 goto error;
243 }
244
245 /* Add quit pipe */
246 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
247 if (ret < 0) {
248 goto error;
249 }
250
251 return 0;
252
253 error:
254 return ret;
255 }
256
257 /*
258 * Check if the thread quit pipe was triggered.
259 *
260 * Return 1 if it was triggered else 0;
261 */
262 static int check_thread_quit_pipe(int fd, uint32_t events)
263 {
264 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
265 return 1;
266 }
267
268 return 0;
269 }
270
271 /*
272 * Remove modules in reverse load order.
273 */
274 static int modprobe_remove_kernel_modules(void)
275 {
276 int ret = 0, i;
277 char modprobe[256];
278
279 for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
280 ret = snprintf(modprobe, sizeof(modprobe),
281 "/sbin/modprobe -r -q %s",
282 kernel_modules_list[i].name);
283 if (ret < 0) {
284 perror("snprintf modprobe -r");
285 goto error;
286 }
287 modprobe[sizeof(modprobe) - 1] = '\0';
288 ret = system(modprobe);
289 if (ret == -1) {
290 ERR("Unable to launch modprobe -r for module %s",
291 kernel_modules_list[i].name);
292 } else if (kernel_modules_list[i].required
293 && WEXITSTATUS(ret) != 0) {
294 ERR("Unable to remove module %s",
295 kernel_modules_list[i].name);
296 } else {
297 DBG("Modprobe removal successful %s",
298 kernel_modules_list[i].name);
299 }
300 }
301
302 error:
303 return ret;
304 }
305
306 /*
307 * Return group ID of the tracing group or -1 if not found.
308 */
309 static gid_t allowed_group(void)
310 {
311 struct group *grp;
312
313 if (opt_tracing_group) {
314 grp = getgrnam(opt_tracing_group);
315 } else {
316 grp = getgrnam(default_tracing_group);
317 }
318 if (!grp) {
319 return -1;
320 } else {
321 return grp->gr_gid;
322 }
323 }
324
325 /*
326 * Init thread quit pipe.
327 *
328 * Return -1 on error or 0 if all pipes are created.
329 */
330 static int init_thread_quit_pipe(void)
331 {
332 int ret;
333
334 ret = pipe2(thread_quit_pipe, O_CLOEXEC);
335 if (ret < 0) {
336 perror("thread quit pipe");
337 goto error;
338 }
339
340 error:
341 return ret;
342 }
343
344 /*
345 * Complete teardown of a kernel session. This free all data structure related
346 * to a kernel session and update counter.
347 */
348 static void teardown_kernel_session(struct ltt_session *session)
349 {
350 if (!session->kernel_session) {
351 DBG3("No kernel session when tearingdown session");
352 return;
353 }
354
355 DBG("Tearing down kernel session");
356
357 /*
358 * If a custom kernel consumer was registered, close the socket before
359 * tearing down the complete kernel session structure
360 */
361 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
362 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
363 }
364
365 trace_kernel_destroy_session(session->kernel_session);
366 }
367
368 /*
369 * Complete teardown of all UST sessions. This will free everything on his path
370 * and destroy the core essence of all ust sessions :)
371 */
372 static void teardown_ust_session(struct ltt_session *session)
373 {
374 int ret;
375
376 if (!session->ust_session) {
377 DBG3("No UST session when tearingdown session");
378 return;
379 }
380
381 DBG("Tearing down UST session(s)");
382
383 ret = ust_app_destroy_trace_all(session->ust_session);
384 if (ret) {
385 ERR("Error in ust_app_destroy_trace_all");
386 }
387
388 trace_ust_destroy_session(session->ust_session);
389 }
390
391 /*
392 * Stop all threads by closing the thread quit pipe.
393 */
394 static void stop_threads(void)
395 {
396 int ret;
397
398 /* Stopping all threads */
399 DBG("Terminating all threads");
400 ret = notify_thread_pipe(thread_quit_pipe[1]);
401 if (ret < 0) {
402 ERR("write error on thread quit pipe");
403 }
404
405 /* Dispatch thread */
406 dispatch_thread_exit = 1;
407 futex_nto1_wake(&ust_cmd_queue.futex);
408 }
409
410 /*
411 * Cleanup the daemon
412 */
413 static void cleanup(void)
414 {
415 int ret;
416 char *cmd;
417 struct ltt_session *sess, *stmp;
418
419 DBG("Cleaning up");
420
421 DBG("Removing %s directory", rundir);
422 ret = asprintf(&cmd, "rm -rf %s", rundir);
423 if (ret < 0) {
424 ERR("asprintf failed. Something is really wrong!");
425 }
426
427 /* Remove lttng run directory */
428 ret = system(cmd);
429 if (ret < 0) {
430 ERR("Unable to clean %s", rundir);
431 }
432 free(cmd);
433
434 DBG("Cleaning up all session");
435
436 /* Destroy session list mutex */
437 if (session_list_ptr != NULL) {
438 pthread_mutex_destroy(&session_list_ptr->lock);
439
440 /* Cleanup ALL session */
441 cds_list_for_each_entry_safe(sess, stmp,
442 &session_list_ptr->head, list) {
443 teardown_kernel_session(sess);
444 teardown_ust_session(sess);
445 free(sess);
446 }
447 }
448
449 DBG("Closing all UST sockets");
450 ust_app_clean_list();
451
452 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
453
454 if (is_root && !opt_no_kernel) {
455 DBG2("Closing kernel fd");
456 close(kernel_tracer_fd);
457 DBG("Unloading kernel modules");
458 modprobe_remove_kernel_modules();
459 }
460
461 close(thread_quit_pipe[0]);
462 close(thread_quit_pipe[1]);
463
464 /* <fun> */
465 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
466 "Matthew, BEET driven development works!%c[%dm",
467 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
468 /* </fun> */
469 }
470
471 /*
472 * Send data on a unix socket using the liblttsessiondcomm API.
473 *
474 * Return lttcomm error code.
475 */
476 static int send_unix_sock(int sock, void *buf, size_t len)
477 {
478 /* Check valid length */
479 if (len <= 0) {
480 return -1;
481 }
482
483 return lttcomm_send_unix_sock(sock, buf, len);
484 }
485
486 /*
487 * Free memory of a command context structure.
488 */
489 static void clean_command_ctx(struct command_ctx **cmd_ctx)
490 {
491 DBG("Clean command context structure");
492 if (*cmd_ctx) {
493 if ((*cmd_ctx)->llm) {
494 free((*cmd_ctx)->llm);
495 }
496 if ((*cmd_ctx)->lsm) {
497 free((*cmd_ctx)->lsm);
498 }
499 free(*cmd_ctx);
500 *cmd_ctx = NULL;
501 }
502 }
503
504 /*
505 * Send all stream fds of kernel channel to the consumer.
506 */
507 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
508 int sock, struct ltt_kernel_channel *channel,
509 uid_t uid, gid_t gid)
510 {
511 int ret;
512 struct ltt_kernel_stream *stream;
513 struct lttcomm_consumer_msg lkm;
514
515 DBG("Sending streams of channel %s to kernel consumer",
516 channel->channel->name);
517
518 /* Send channel */
519 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
520 lkm.u.channel.channel_key = channel->fd;
521 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
522 lkm.u.channel.mmap_len = 0; /* for kernel */
523 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
524 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
525 if (ret < 0) {
526 perror("send consumer channel");
527 goto error;
528 }
529
530 /* Send streams */
531 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
532 if (!stream->fd) {
533 continue;
534 }
535 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
536 lkm.u.stream.channel_key = channel->fd;
537 lkm.u.stream.stream_key = stream->fd;
538 lkm.u.stream.state = stream->state;
539 lkm.u.stream.output = channel->channel->attr.output;
540 lkm.u.stream.mmap_len = 0; /* for kernel */
541 lkm.u.stream.uid = uid;
542 lkm.u.stream.gid = gid;
543 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
544 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
545 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
546 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
547 if (ret < 0) {
548 perror("send consumer stream");
549 goto error;
550 }
551 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
552 if (ret < 0) {
553 perror("send consumer stream ancillary data");
554 goto error;
555 }
556 }
557
558 DBG("consumer channel streams sent");
559
560 return 0;
561
562 error:
563 return ret;
564 }
565
566 /*
567 * Send all stream fds of the kernel session to the consumer.
568 */
569 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
570 struct ltt_kernel_session *session)
571 {
572 int ret;
573 struct ltt_kernel_channel *chan;
574 struct lttcomm_consumer_msg lkm;
575 int sock = session->consumer_fd;
576
577 DBG("Sending metadata stream fd");
578
579 /* Extra protection. It's NOT supposed to be set to 0 at this point */
580 if (session->consumer_fd == 0) {
581 session->consumer_fd = consumer_data->cmd_sock;
582 }
583
584 if (session->metadata_stream_fd != 0) {
585 /* Send metadata channel fd */
586 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
587 lkm.u.channel.channel_key = session->metadata->fd;
588 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
589 lkm.u.channel.mmap_len = 0; /* for kernel */
590 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
591 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
592 if (ret < 0) {
593 perror("send consumer channel");
594 goto error;
595 }
596
597 /* Send metadata stream fd */
598 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
599 lkm.u.stream.channel_key = session->metadata->fd;
600 lkm.u.stream.stream_key = session->metadata_stream_fd;
601 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
602 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
603 lkm.u.stream.mmap_len = 0; /* for kernel */
604 lkm.u.stream.uid = session->uid;
605 lkm.u.stream.gid = session->gid;
606 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
607 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
608 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
609 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
610 if (ret < 0) {
611 perror("send consumer stream");
612 goto error;
613 }
614 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
615 if (ret < 0) {
616 perror("send consumer stream");
617 goto error;
618 }
619 }
620
621 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
622 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
623 session->uid, session->gid);
624 if (ret < 0) {
625 goto error;
626 }
627 }
628
629 DBG("consumer fds (metadata and channel streams) sent");
630
631 return 0;
632
633 error:
634 return ret;
635 }
636
637 /*
638 * Notify UST applications using the shm mmap futex.
639 */
640 static int notify_ust_apps(int active)
641 {
642 char *wait_shm_mmap;
643
644 DBG("Notifying applications of session daemon state: %d", active);
645
646 /* See shm.c for this call implying mmap, shm and futex calls */
647 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
648 if (wait_shm_mmap == NULL) {
649 goto error;
650 }
651
652 /* Wake waiting process */
653 futex_wait_update((int32_t *) wait_shm_mmap, active);
654
655 /* Apps notified successfully */
656 return 0;
657
658 error:
659 return -1;
660 }
661
662 /*
663 * Setup the outgoing data buffer for the response (llm) by allocating the
664 * right amount of memory and copying the original information from the lsm
665 * structure.
666 *
667 * Return total size of the buffer pointed by buf.
668 */
669 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
670 {
671 int ret, buf_size;
672
673 buf_size = size;
674
675 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
676 if (cmd_ctx->llm == NULL) {
677 perror("zmalloc");
678 ret = -ENOMEM;
679 goto error;
680 }
681
682 /* Copy common data */
683 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
684 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
685
686 cmd_ctx->llm->data_size = size;
687 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
688
689 return buf_size;
690
691 error:
692 return ret;
693 }
694
695 /*
696 * Update the kernel poll set of all channel fd available over all tracing
697 * session. Add the wakeup pipe at the end of the set.
698 */
699 static int update_kernel_poll(struct lttng_poll_event *events)
700 {
701 int ret;
702 struct ltt_session *session;
703 struct ltt_kernel_channel *channel;
704
705 DBG("Updating kernel poll set");
706
707 session_lock_list();
708 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
709 session_lock(session);
710 if (session->kernel_session == NULL) {
711 session_unlock(session);
712 continue;
713 }
714
715 cds_list_for_each_entry(channel,
716 &session->kernel_session->channel_list.head, list) {
717 /* Add channel fd to the kernel poll set */
718 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
719 if (ret < 0) {
720 session_unlock(session);
721 goto error;
722 }
723 DBG("Channel fd %d added to kernel set", channel->fd);
724 }
725 session_unlock(session);
726 }
727 session_unlock_list();
728
729 return 0;
730
731 error:
732 session_unlock_list();
733 return -1;
734 }
735
736 /*
737 * Find the channel fd from 'fd' over all tracing session. When found, check
738 * for new channel stream and send those stream fds to the kernel consumer.
739 *
740 * Useful for CPU hotplug feature.
741 */
742 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
743 {
744 int ret = 0;
745 struct ltt_session *session;
746 struct ltt_kernel_channel *channel;
747
748 DBG("Updating kernel streams for channel fd %d", fd);
749
750 session_lock_list();
751 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
752 session_lock(session);
753 if (session->kernel_session == NULL) {
754 session_unlock(session);
755 continue;
756 }
757
758 /* This is not suppose to be 0 but this is an extra security check */
759 if (session->kernel_session->consumer_fd == 0) {
760 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
761 }
762
763 cds_list_for_each_entry(channel,
764 &session->kernel_session->channel_list.head, list) {
765 if (channel->fd == fd) {
766 DBG("Channel found, updating kernel streams");
767 ret = kernel_open_channel_stream(channel);
768 if (ret < 0) {
769 goto error;
770 }
771
772 /*
773 * Have we already sent fds to the consumer? If yes, it means
774 * that tracing is started so it is safe to send our updated
775 * stream fds.
776 */
777 if (session->kernel_session->consumer_fds_sent == 1) {
778 ret = send_kconsumer_channel_streams(consumer_data,
779 session->kernel_session->consumer_fd, channel,
780 session->uid, session->gid);
781 if (ret < 0) {
782 goto error;
783 }
784 }
785 goto error;
786 }
787 }
788 session_unlock(session);
789 }
790 session_unlock_list();
791 return ret;
792
793 error:
794 session_unlock(session);
795 session_unlock_list();
796 return ret;
797 }
798
799 /*
800 * For each tracing session, update newly registered apps.
801 */
802 static void update_ust_app(int app_sock)
803 {
804 struct ltt_session *sess, *stmp;
805
806 /* For all tracing session(s) */
807 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
808 if (sess->ust_session) {
809 ust_app_global_update(sess->ust_session, app_sock);
810 }
811 }
812 }
813
814 /*
815 * This thread manage event coming from the kernel.
816 *
817 * Features supported in this thread:
818 * -) CPU Hotplug
819 */
820 static void *thread_manage_kernel(void *data)
821 {
822 int ret, i, pollfd, update_poll_flag = 1;
823 uint32_t revents, nb_fd;
824 char tmp;
825 struct lttng_poll_event events;
826
827 DBG("Thread manage kernel started");
828
829 ret = create_thread_poll_set(&events, 2);
830 if (ret < 0) {
831 goto error;
832 }
833
834 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
835 if (ret < 0) {
836 goto error;
837 }
838
839 while (1) {
840 if (update_poll_flag == 1) {
841 /*
842 * Reset number of fd in the poll set. Always 2 since there is the thread
843 * quit pipe and the kernel pipe.
844 */
845 events.nb_fd = 2;
846
847 ret = update_kernel_poll(&events);
848 if (ret < 0) {
849 goto error;
850 }
851 update_poll_flag = 0;
852 }
853
854 nb_fd = LTTNG_POLL_GETNB(&events);
855
856 DBG("Thread kernel polling on %d fds", nb_fd);
857
858 /* Zeroed the poll events */
859 lttng_poll_reset(&events);
860
861 /* Poll infinite value of time */
862 ret = lttng_poll_wait(&events, -1);
863 if (ret < 0) {
864 goto error;
865 } else if (ret == 0) {
866 /* Should not happen since timeout is infinite */
867 ERR("Return value of poll is 0 with an infinite timeout.\n"
868 "This should not have happened! Continuing...");
869 continue;
870 }
871
872 for (i = 0; i < nb_fd; i++) {
873 /* Fetch once the poll data */
874 revents = LTTNG_POLL_GETEV(&events, i);
875 pollfd = LTTNG_POLL_GETFD(&events, i);
876
877 /* Thread quit pipe has been closed. Killing thread. */
878 ret = check_thread_quit_pipe(pollfd, revents);
879 if (ret) {
880 goto error;
881 }
882
883 /* Check for data on kernel pipe */
884 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
885 ret = read(kernel_poll_pipe[0], &tmp, 1);
886 update_poll_flag = 1;
887 continue;
888 } else {
889 /*
890 * New CPU detected by the kernel. Adding kernel stream to
891 * kernel session and updating the kernel consumer
892 */
893 if (revents & LPOLLIN) {
894 ret = update_kernel_stream(&kconsumer_data, pollfd);
895 if (ret < 0) {
896 continue;
897 }
898 break;
899 /*
900 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
901 * and unregister kernel stream at this point.
902 */
903 }
904 }
905 }
906 }
907
908 error:
909 DBG("Kernel thread dying");
910 close(kernel_poll_pipe[0]);
911 close(kernel_poll_pipe[1]);
912
913 lttng_poll_clean(&events);
914
915 return NULL;
916 }
917
918 /*
919 * This thread manage the consumer error sent back to the session daemon.
920 */
921 static void *thread_manage_consumer(void *data)
922 {
923 int sock = 0, i, ret, pollfd;
924 uint32_t revents, nb_fd;
925 enum lttcomm_return_code code;
926 struct lttng_poll_event events;
927 struct consumer_data *consumer_data = data;
928
929 DBG("[thread] Manage consumer started");
930
931 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
932 if (ret < 0) {
933 goto error;
934 }
935
936 /*
937 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
938 * Nothing more will be added to this poll set.
939 */
940 ret = create_thread_poll_set(&events, 2);
941 if (ret < 0) {
942 goto error;
943 }
944
945 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
946 if (ret < 0) {
947 goto error;
948 }
949
950 nb_fd = LTTNG_POLL_GETNB(&events);
951
952 /* Inifinite blocking call, waiting for transmission */
953 ret = lttng_poll_wait(&events, -1);
954 if (ret < 0) {
955 goto error;
956 }
957
958 for (i = 0; i < nb_fd; i++) {
959 /* Fetch once the poll data */
960 revents = LTTNG_POLL_GETEV(&events, i);
961 pollfd = LTTNG_POLL_GETFD(&events, i);
962
963 /* Thread quit pipe has been closed. Killing thread. */
964 ret = check_thread_quit_pipe(pollfd, revents);
965 if (ret) {
966 goto error;
967 }
968
969 /* Event on the registration socket */
970 if (pollfd == consumer_data->err_sock) {
971 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
972 ERR("consumer err socket poll error");
973 goto error;
974 }
975 }
976 }
977
978 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
979 if (sock < 0) {
980 goto error;
981 }
982
983 DBG2("Receiving code from consumer err_sock");
984
985 /* Getting status code from kconsumerd */
986 ret = lttcomm_recv_unix_sock(sock, &code,
987 sizeof(enum lttcomm_return_code));
988 if (ret <= 0) {
989 goto error;
990 }
991
992 if (code == CONSUMERD_COMMAND_SOCK_READY) {
993 consumer_data->cmd_sock =
994 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
995 if (consumer_data->cmd_sock < 0) {
996 sem_post(&consumer_data->sem);
997 PERROR("consumer connect");
998 goto error;
999 }
1000 /* Signal condition to tell that the kconsumerd is ready */
1001 sem_post(&consumer_data->sem);
1002 DBG("consumer command socket ready");
1003 } else {
1004 ERR("consumer error when waiting for SOCK_READY : %s",
1005 lttcomm_get_readable_code(-code));
1006 goto error;
1007 }
1008
1009 /* Remove the kconsumerd error sock since we've established a connexion */
1010 ret = lttng_poll_del(&events, consumer_data->err_sock);
1011 if (ret < 0) {
1012 goto error;
1013 }
1014
1015 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1016 if (ret < 0) {
1017 goto error;
1018 }
1019
1020 /* Update number of fd */
1021 nb_fd = LTTNG_POLL_GETNB(&events);
1022
1023 /* Inifinite blocking call, waiting for transmission */
1024 ret = lttng_poll_wait(&events, -1);
1025 if (ret < 0) {
1026 goto error;
1027 }
1028
1029 for (i = 0; i < nb_fd; i++) {
1030 /* Fetch once the poll data */
1031 revents = LTTNG_POLL_GETEV(&events, i);
1032 pollfd = LTTNG_POLL_GETFD(&events, i);
1033
1034 /* Thread quit pipe has been closed. Killing thread. */
1035 ret = check_thread_quit_pipe(pollfd, revents);
1036 if (ret) {
1037 goto error;
1038 }
1039
1040 /* Event on the kconsumerd socket */
1041 if (pollfd == sock) {
1042 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1043 ERR("consumer err socket second poll error");
1044 goto error;
1045 }
1046 }
1047 }
1048
1049 /* Wait for any kconsumerd error */
1050 ret = lttcomm_recv_unix_sock(sock, &code,
1051 sizeof(enum lttcomm_return_code));
1052 if (ret <= 0) {
1053 ERR("consumer closed the command socket");
1054 goto error;
1055 }
1056
1057 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1058
1059 error:
1060 DBG("consumer thread dying");
1061 close(consumer_data->err_sock);
1062 close(consumer_data->cmd_sock);
1063 close(sock);
1064
1065 unlink(consumer_data->err_unix_sock_path);
1066 unlink(consumer_data->cmd_unix_sock_path);
1067 consumer_data->pid = 0;
1068
1069 lttng_poll_clean(&events);
1070
1071 return NULL;
1072 }
1073
1074 /*
1075 * This thread manage application communication.
1076 */
1077 static void *thread_manage_apps(void *data)
1078 {
1079 int i, ret, pollfd;
1080 uint32_t revents, nb_fd;
1081 struct ust_command ust_cmd;
1082 struct lttng_poll_event events;
1083
1084 DBG("[thread] Manage application started");
1085
1086 rcu_register_thread();
1087 rcu_thread_online();
1088
1089 ret = create_thread_poll_set(&events, 2);
1090 if (ret < 0) {
1091 goto error;
1092 }
1093
1094 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1095 if (ret < 0) {
1096 goto error;
1097 }
1098
1099 while (1) {
1100 /* Zeroed the events structure */
1101 lttng_poll_reset(&events);
1102
1103 nb_fd = LTTNG_POLL_GETNB(&events);
1104
1105 DBG("Apps thread polling on %d fds", nb_fd);
1106
1107 /* Inifinite blocking call, waiting for transmission */
1108 ret = lttng_poll_wait(&events, -1);
1109 if (ret < 0) {
1110 goto error;
1111 }
1112
1113 for (i = 0; i < nb_fd; i++) {
1114 /* Fetch once the poll data */
1115 revents = LTTNG_POLL_GETEV(&events, i);
1116 pollfd = LTTNG_POLL_GETFD(&events, i);
1117
1118 /* Thread quit pipe has been closed. Killing thread. */
1119 ret = check_thread_quit_pipe(pollfd, revents);
1120 if (ret) {
1121 goto error;
1122 }
1123
1124 /* Inspect the apps cmd pipe */
1125 if (pollfd == apps_cmd_pipe[0]) {
1126 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1127 ERR("Apps command pipe error");
1128 goto error;
1129 } else if (revents & LPOLLIN) {
1130 /* Empty pipe */
1131 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1132 if (ret < 0 || ret < sizeof(ust_cmd)) {
1133 perror("read apps cmd pipe");
1134 goto error;
1135 }
1136
1137 /* Register applicaton to the session daemon */
1138 ret = ust_app_register(&ust_cmd.reg_msg,
1139 ust_cmd.sock);
1140 if (ret == -ENOMEM) {
1141 goto error;
1142 } else if (ret < 0) {
1143 break;
1144 }
1145
1146 /*
1147 * Add channel(s) and event(s) to newly registered apps
1148 * from lttng global UST domain.
1149 */
1150 update_ust_app(ust_cmd.sock);
1151
1152 ret = ust_app_register_done(ust_cmd.sock);
1153 if (ret < 0) {
1154 /*
1155 * If the registration is not possible, we simply
1156 * unregister the apps and continue
1157 */
1158 ust_app_unregister(ust_cmd.sock);
1159 } else {
1160 /*
1161 * We just need here to monitor the close of the UST
1162 * socket and poll set monitor those by default.
1163 */
1164 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1165 if (ret < 0) {
1166 goto error;
1167 }
1168
1169 DBG("Apps with sock %d added to poll set",
1170 ust_cmd.sock);
1171 }
1172
1173 break;
1174 }
1175 } else {
1176 /*
1177 * At this point, we know that a registered application made
1178 * the event at poll_wait.
1179 */
1180 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1181 /* Removing from the poll set */
1182 ret = lttng_poll_del(&events, pollfd);
1183 if (ret < 0) {
1184 goto error;
1185 }
1186
1187 /* Socket closed on remote end. */
1188 ust_app_unregister(pollfd);
1189 break;
1190 }
1191 }
1192 }
1193 }
1194
1195 error:
1196 DBG("Application communication apps dying");
1197 close(apps_cmd_pipe[0]);
1198 close(apps_cmd_pipe[1]);
1199
1200 lttng_poll_clean(&events);
1201
1202 rcu_thread_offline();
1203 rcu_unregister_thread();
1204 return NULL;
1205 }
1206
1207 /*
1208 * Dispatch request from the registration threads to the application
1209 * communication thread.
1210 */
1211 static void *thread_dispatch_ust_registration(void *data)
1212 {
1213 int ret;
1214 struct cds_wfq_node *node;
1215 struct ust_command *ust_cmd = NULL;
1216
1217 DBG("[thread] Dispatch UST command started");
1218
1219 while (!dispatch_thread_exit) {
1220 /* Atomically prepare the queue futex */
1221 futex_nto1_prepare(&ust_cmd_queue.futex);
1222
1223 do {
1224 /* Dequeue command for registration */
1225 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1226 if (node == NULL) {
1227 DBG("Woken up but nothing in the UST command queue");
1228 /* Continue thread execution */
1229 break;
1230 }
1231
1232 ust_cmd = caa_container_of(node, struct ust_command, node);
1233
1234 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1235 " gid:%d sock:%d name:%s (version %d.%d)",
1236 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1237 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1238 ust_cmd->sock, ust_cmd->reg_msg.name,
1239 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1240 /*
1241 * Inform apps thread of the new application registration. This
1242 * call is blocking so we can be assured that the data will be read
1243 * at some point in time or wait to the end of the world :)
1244 */
1245 ret = write(apps_cmd_pipe[1], ust_cmd,
1246 sizeof(struct ust_command));
1247 if (ret < 0) {
1248 perror("write apps cmd pipe");
1249 if (errno == EBADF) {
1250 /*
1251 * We can't inform the application thread to process
1252 * registration. We will exit or else application
1253 * registration will not occur and tracing will never
1254 * start.
1255 */
1256 goto error;
1257 }
1258 }
1259 free(ust_cmd);
1260 } while (node != NULL);
1261
1262 /* Futex wait on queue. Blocking call on futex() */
1263 futex_nto1_wait(&ust_cmd_queue.futex);
1264 }
1265
1266 error:
1267 DBG("Dispatch thread dying");
1268 return NULL;
1269 }
1270
1271 /*
1272 * This thread manage application registration.
1273 */
1274 static void *thread_registration_apps(void *data)
1275 {
1276 int sock = 0, i, ret, pollfd;
1277 uint32_t revents, nb_fd;
1278 struct lttng_poll_event events;
1279 /*
1280 * Get allocated in this thread, enqueued to a global queue, dequeued and
1281 * freed in the manage apps thread.
1282 */
1283 struct ust_command *ust_cmd = NULL;
1284
1285 DBG("[thread] Manage application registration started");
1286
1287 ret = lttcomm_listen_unix_sock(apps_sock);
1288 if (ret < 0) {
1289 goto error;
1290 }
1291
1292 /*
1293 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1294 * more will be added to this poll set.
1295 */
1296 ret = create_thread_poll_set(&events, 2);
1297 if (ret < 0) {
1298 goto error;
1299 }
1300
1301 /* Add the application registration socket */
1302 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1303 if (ret < 0) {
1304 goto error;
1305 }
1306
1307 /* Notify all applications to register */
1308 ret = notify_ust_apps(1);
1309 if (ret < 0) {
1310 ERR("Failed to notify applications or create the wait shared memory.\n"
1311 "Execution continues but there might be problem for already\n"
1312 "running applications that wishes to register.");
1313 }
1314
1315 while (1) {
1316 DBG("Accepting application registration");
1317
1318 nb_fd = LTTNG_POLL_GETNB(&events);
1319
1320 /* Inifinite blocking call, waiting for transmission */
1321 ret = lttng_poll_wait(&events, -1);
1322 if (ret < 0) {
1323 goto error;
1324 }
1325
1326 for (i = 0; i < nb_fd; i++) {
1327 /* Fetch once the poll data */
1328 revents = LTTNG_POLL_GETEV(&events, i);
1329 pollfd = LTTNG_POLL_GETFD(&events, i);
1330
1331 /* Thread quit pipe has been closed. Killing thread. */
1332 ret = check_thread_quit_pipe(pollfd, revents);
1333 if (ret) {
1334 goto error;
1335 }
1336
1337 /* Event on the registration socket */
1338 if (pollfd == apps_sock) {
1339 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1340 ERR("Register apps socket poll error");
1341 goto error;
1342 } else if (revents & LPOLLIN) {
1343 sock = lttcomm_accept_unix_sock(apps_sock);
1344 if (sock < 0) {
1345 goto error;
1346 }
1347
1348 /* Create UST registration command for enqueuing */
1349 ust_cmd = zmalloc(sizeof(struct ust_command));
1350 if (ust_cmd == NULL) {
1351 perror("ust command zmalloc");
1352 goto error;
1353 }
1354
1355 /*
1356 * Using message-based transmissions to ensure we don't
1357 * have to deal with partially received messages.
1358 */
1359 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1360 sizeof(struct ust_register_msg));
1361 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1362 if (ret < 0) {
1363 perror("lttcomm_recv_unix_sock register apps");
1364 } else {
1365 ERR("Wrong size received on apps register");
1366 }
1367 free(ust_cmd);
1368 close(sock);
1369 continue;
1370 }
1371
1372 ust_cmd->sock = sock;
1373
1374 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1375 " gid:%d sock:%d name:%s (version %d.%d)",
1376 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1377 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1378 ust_cmd->sock, ust_cmd->reg_msg.name,
1379 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1380
1381 /*
1382 * Lock free enqueue the registration request. The red pill
1383 * has been taken! This apps will be part of the *system*.
1384 */
1385 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1386
1387 /*
1388 * Wake the registration queue futex. Implicit memory
1389 * barrier with the exchange in cds_wfq_enqueue.
1390 */
1391 futex_nto1_wake(&ust_cmd_queue.futex);
1392 }
1393 }
1394 }
1395 }
1396
1397 error:
1398 DBG("UST Registration thread dying");
1399
1400 /* Notify that the registration thread is gone */
1401 notify_ust_apps(0);
1402
1403 close(apps_sock);
1404 close(sock);
1405 unlink(apps_unix_sock_path);
1406
1407 lttng_poll_clean(&events);
1408
1409 return NULL;
1410 }
1411
1412 /*
1413 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1414 * exec or it will fails.
1415 */
1416 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1417 {
1418 int ret;
1419 struct timespec timeout;
1420
1421 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1422 timeout.tv_nsec = 0;
1423
1424 /* Setup semaphore */
1425 ret = sem_init(&consumer_data->sem, 0, 0);
1426 if (ret < 0) {
1427 PERROR("sem_init consumer semaphore");
1428 goto error;
1429 }
1430
1431 ret = pthread_create(&consumer_data->thread, NULL,
1432 thread_manage_consumer, consumer_data);
1433 if (ret != 0) {
1434 PERROR("pthread_create consumer");
1435 ret = -1;
1436 goto error;
1437 }
1438
1439 /* Get time for sem_timedwait absolute timeout */
1440 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1441 if (ret < 0) {
1442 PERROR("clock_gettime spawn consumer");
1443 /* Infinite wait for the kconsumerd thread to be ready */
1444 ret = sem_wait(&consumer_data->sem);
1445 } else {
1446 /* Normal timeout if the gettime was successful */
1447 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1448 ret = sem_timedwait(&consumer_data->sem, &timeout);
1449 }
1450
1451 if (ret < 0) {
1452 if (errno == ETIMEDOUT) {
1453 /*
1454 * Call has timed out so we kill the kconsumerd_thread and return
1455 * an error.
1456 */
1457 ERR("The consumer thread was never ready. Killing it");
1458 ret = pthread_cancel(consumer_data->thread);
1459 if (ret < 0) {
1460 PERROR("pthread_cancel consumer thread");
1461 }
1462 } else {
1463 PERROR("semaphore wait failed consumer thread");
1464 }
1465 goto error;
1466 }
1467
1468 pthread_mutex_lock(&consumer_data->pid_mutex);
1469 if (consumer_data->pid == 0) {
1470 ERR("Kconsumerd did not start");
1471 pthread_mutex_unlock(&consumer_data->pid_mutex);
1472 goto error;
1473 }
1474 pthread_mutex_unlock(&consumer_data->pid_mutex);
1475
1476 return 0;
1477
1478 error:
1479 return ret;
1480 }
1481
1482 /*
1483 * Join consumer thread
1484 */
1485 static int join_consumer_thread(struct consumer_data *consumer_data)
1486 {
1487 void *status;
1488 int ret;
1489
1490 if (consumer_data->pid != 0) {
1491 ret = kill(consumer_data->pid, SIGTERM);
1492 if (ret) {
1493 ERR("Error killing consumer daemon");
1494 return ret;
1495 }
1496 return pthread_join(consumer_data->thread, &status);
1497 } else {
1498 return 0;
1499 }
1500 }
1501
1502 /*
1503 * Fork and exec a consumer daemon (consumerd).
1504 *
1505 * Return pid if successful else -1.
1506 */
1507 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1508 {
1509 int ret;
1510 pid_t pid;
1511 const char *consumer_to_use;
1512 const char *verbosity;
1513 struct stat st;
1514
1515 DBG("Spawning consumerd");
1516
1517 pid = fork();
1518 if (pid == 0) {
1519 /*
1520 * Exec consumerd.
1521 */
1522 if (opt_verbose_consumer) {
1523 verbosity = "--verbose";
1524 } else {
1525 verbosity = "--quiet";
1526 }
1527 switch (consumer_data->type) {
1528 case LTTNG_CONSUMER_KERNEL:
1529 /*
1530 * Find out which consumerd to execute. We will first try the
1531 * 64-bit path, then the sessiond's installation directory, and
1532 * fallback on the 32-bit one,
1533 */
1534 DBG3("Looking for a kernel consumer at these locations:");
1535 DBG3(" 1) %s", consumerd64_bin);
1536 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1537 DBG3(" 3) %s", consumerd32_bin);
1538 if (stat(consumerd64_bin, &st) == 0) {
1539 DBG3("Found location #1");
1540 consumer_to_use = consumerd64_bin;
1541 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1542 DBG3("Found location #2");
1543 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1544 } else if (stat(consumerd32_bin, &st) == 0) {
1545 DBG3("Found location #3");
1546 consumer_to_use = consumerd32_bin;
1547 } else {
1548 DBG("Could not find any valid consumerd executable");
1549 break;
1550 }
1551 DBG("Using kernel consumer at: %s", consumer_to_use);
1552 execl(consumer_to_use,
1553 "lttng-consumerd", verbosity, "-k",
1554 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1555 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1556 NULL);
1557 break;
1558 case LTTNG_CONSUMER64_UST:
1559 {
1560 char *tmpnew = NULL;
1561
1562 if (consumerd64_libdir[0] != '\0') {
1563 char *tmp;
1564 size_t tmplen;
1565
1566 tmp = getenv("LD_LIBRARY_PATH");
1567 if (!tmp) {
1568 tmp = "";
1569 }
1570 tmplen = strlen("LD_LIBRARY_PATH=")
1571 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1572 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1573 if (!tmpnew) {
1574 ret = -ENOMEM;
1575 goto error;
1576 }
1577 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1578 strcat(tmpnew, consumerd64_libdir);
1579 if (tmp[0] != '\0') {
1580 strcat(tmpnew, ":");
1581 strcat(tmpnew, tmp);
1582 }
1583 ret = putenv(tmpnew);
1584 if (ret) {
1585 ret = -errno;
1586 goto error;
1587 }
1588 }
1589 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1590 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1591 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1592 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1593 NULL);
1594 if (consumerd64_libdir[0] != '\0') {
1595 free(tmpnew);
1596 }
1597 if (ret) {
1598 goto error;
1599 }
1600 break;
1601 }
1602 case LTTNG_CONSUMER32_UST:
1603 {
1604 char *tmpnew = NULL;
1605
1606 if (consumerd32_libdir[0] != '\0') {
1607 char *tmp;
1608 size_t tmplen;
1609
1610 tmp = getenv("LD_LIBRARY_PATH");
1611 if (!tmp) {
1612 tmp = "";
1613 }
1614 tmplen = strlen("LD_LIBRARY_PATH=")
1615 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1616 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1617 if (!tmpnew) {
1618 ret = -ENOMEM;
1619 goto error;
1620 }
1621 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1622 strcat(tmpnew, consumerd32_libdir);
1623 if (tmp[0] != '\0') {
1624 strcat(tmpnew, ":");
1625 strcat(tmpnew, tmp);
1626 }
1627 ret = putenv(tmpnew);
1628 if (ret) {
1629 ret = -errno;
1630 goto error;
1631 }
1632 }
1633 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1634 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1635 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1636 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1637 NULL);
1638 if (consumerd32_libdir[0] != '\0') {
1639 free(tmpnew);
1640 }
1641 if (ret) {
1642 goto error;
1643 }
1644 break;
1645 }
1646 default:
1647 perror("unknown consumer type");
1648 exit(EXIT_FAILURE);
1649 }
1650 if (errno != 0) {
1651 perror("kernel start consumer exec");
1652 }
1653 exit(EXIT_FAILURE);
1654 } else if (pid > 0) {
1655 ret = pid;
1656 } else {
1657 perror("start consumer fork");
1658 ret = -errno;
1659 }
1660 error:
1661 return ret;
1662 }
1663
1664 /*
1665 * Spawn the consumerd daemon and session daemon thread.
1666 */
1667 static int start_consumerd(struct consumer_data *consumer_data)
1668 {
1669 int ret;
1670
1671 pthread_mutex_lock(&consumer_data->pid_mutex);
1672 if (consumer_data->pid != 0) {
1673 pthread_mutex_unlock(&consumer_data->pid_mutex);
1674 goto end;
1675 }
1676
1677 ret = spawn_consumerd(consumer_data);
1678 if (ret < 0) {
1679 ERR("Spawning consumerd failed");
1680 pthread_mutex_unlock(&consumer_data->pid_mutex);
1681 goto error;
1682 }
1683
1684 /* Setting up the consumer_data pid */
1685 consumer_data->pid = ret;
1686 DBG2("Consumer pid %d", consumer_data->pid);
1687 pthread_mutex_unlock(&consumer_data->pid_mutex);
1688
1689 DBG2("Spawning consumer control thread");
1690 ret = spawn_consumer_thread(consumer_data);
1691 if (ret < 0) {
1692 ERR("Fatal error spawning consumer control thread");
1693 goto error;
1694 }
1695
1696 end:
1697 return 0;
1698
1699 error:
1700 return ret;
1701 }
1702
1703 /*
1704 * modprobe_kernel_modules
1705 */
1706 static int modprobe_kernel_modules(void)
1707 {
1708 int ret = 0, i;
1709 char modprobe[256];
1710
1711 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1712 ret = snprintf(modprobe, sizeof(modprobe),
1713 "/sbin/modprobe %s%s",
1714 kernel_modules_list[i].required ? "" : "-q ",
1715 kernel_modules_list[i].name);
1716 if (ret < 0) {
1717 perror("snprintf modprobe");
1718 goto error;
1719 }
1720 modprobe[sizeof(modprobe) - 1] = '\0';
1721 ret = system(modprobe);
1722 if (ret == -1) {
1723 ERR("Unable to launch modprobe for module %s",
1724 kernel_modules_list[i].name);
1725 } else if (kernel_modules_list[i].required
1726 && WEXITSTATUS(ret) != 0) {
1727 ERR("Unable to load module %s",
1728 kernel_modules_list[i].name);
1729 } else {
1730 DBG("Modprobe successfully %s",
1731 kernel_modules_list[i].name);
1732 }
1733 }
1734
1735 error:
1736 return ret;
1737 }
1738
1739 /*
1740 * mount_debugfs
1741 */
1742 static int mount_debugfs(char *path)
1743 {
1744 int ret;
1745 char *type = "debugfs";
1746
1747 ret = run_as_mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1748 if (ret < 0) {
1749 PERROR("Cannot create debugfs path");
1750 goto error;
1751 }
1752
1753 ret = mount(type, path, type, 0, NULL);
1754 if (ret < 0) {
1755 PERROR("Cannot mount debugfs");
1756 goto error;
1757 }
1758
1759 DBG("Mounted debugfs successfully at %s", path);
1760
1761 error:
1762 return ret;
1763 }
1764
1765 /*
1766 * Setup necessary data for kernel tracer action.
1767 */
1768 static void init_kernel_tracer(void)
1769 {
1770 int ret;
1771 char *proc_mounts = "/proc/mounts";
1772 char line[256];
1773 char *debugfs_path = NULL, *lttng_path = NULL;
1774 FILE *fp;
1775
1776 /* Detect debugfs */
1777 fp = fopen(proc_mounts, "r");
1778 if (fp == NULL) {
1779 ERR("Unable to probe %s", proc_mounts);
1780 goto error;
1781 }
1782
1783 while (fgets(line, sizeof(line), fp) != NULL) {
1784 if (strstr(line, "debugfs") != NULL) {
1785 /* Remove first string */
1786 strtok(line, " ");
1787 /* Dup string here so we can reuse line later on */
1788 debugfs_path = strdup(strtok(NULL, " "));
1789 DBG("Got debugfs path : %s", debugfs_path);
1790 break;
1791 }
1792 }
1793
1794 fclose(fp);
1795
1796 /* Mount debugfs if needded */
1797 if (debugfs_path == NULL) {
1798 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1799 if (ret < 0) {
1800 perror("asprintf debugfs path");
1801 goto error;
1802 }
1803 ret = mount_debugfs(debugfs_path);
1804 if (ret < 0) {
1805 perror("Cannot mount debugfs");
1806 goto error;
1807 }
1808 }
1809
1810 /* Modprobe lttng kernel modules */
1811 ret = modprobe_kernel_modules();
1812 if (ret < 0) {
1813 goto error;
1814 }
1815
1816 /* Setup lttng kernel path */
1817 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1818 if (ret < 0) {
1819 perror("asprintf lttng path");
1820 goto error;
1821 }
1822
1823 /* Open debugfs lttng */
1824 kernel_tracer_fd = open(lttng_path, O_RDWR);
1825 if (kernel_tracer_fd < 0) {
1826 DBG("Failed to open %s", lttng_path);
1827 goto error;
1828 }
1829
1830 free(lttng_path);
1831 free(debugfs_path);
1832 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1833 return;
1834
1835 error:
1836 if (lttng_path) {
1837 free(lttng_path);
1838 }
1839 if (debugfs_path) {
1840 free(debugfs_path);
1841 }
1842 WARN("No kernel tracer available");
1843 kernel_tracer_fd = 0;
1844 return;
1845 }
1846
1847 /*
1848 * Init tracing by creating trace directory and sending fds kernel consumer.
1849 */
1850 static int init_kernel_tracing(struct ltt_kernel_session *session)
1851 {
1852 int ret = 0;
1853
1854 if (session->consumer_fds_sent == 0) {
1855 /*
1856 * Assign default kernel consumer socket if no consumer assigned to the
1857 * kernel session. At this point, it's NOT suppose to be 0 but this is
1858 * an extra security check.
1859 */
1860 if (session->consumer_fd == 0) {
1861 session->consumer_fd = kconsumer_data.cmd_sock;
1862 }
1863
1864 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1865 if (ret < 0) {
1866 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1867 goto error;
1868 }
1869
1870 session->consumer_fds_sent = 1;
1871 }
1872
1873 error:
1874 return ret;
1875 }
1876
1877 /*
1878 * Create an UST session and add it to the session ust list.
1879 */
1880 static int create_ust_session(struct ltt_session *session,
1881 struct lttng_domain *domain)
1882 {
1883 struct ltt_ust_session *lus = NULL;
1884 int ret;
1885
1886 switch (domain->type) {
1887 case LTTNG_DOMAIN_UST:
1888 break;
1889 default:
1890 ret = LTTCOMM_UNKNOWN_DOMAIN;
1891 goto error;
1892 }
1893
1894 DBG("Creating UST session");
1895
1896 lus = trace_ust_create_session(session->path, session->id, domain);
1897 if (lus == NULL) {
1898 ret = LTTCOMM_UST_SESS_FAIL;
1899 goto error;
1900 }
1901
1902 ret = run_as_mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1903 session->uid, session->gid);
1904 if (ret < 0) {
1905 if (ret != -EEXIST) {
1906 ERR("Trace directory creation error");
1907 ret = LTTCOMM_UST_SESS_FAIL;
1908 goto error;
1909 }
1910 }
1911
1912 /* The domain type dictate different actions on session creation */
1913 switch (domain->type) {
1914 case LTTNG_DOMAIN_UST:
1915 /* No ustctl for the global UST domain */
1916 break;
1917 default:
1918 ERR("Unknown UST domain on create session %d", domain->type);
1919 goto error;
1920 }
1921 lus->uid = session->uid;
1922 lus->gid = session->gid;
1923 session->ust_session = lus;
1924
1925 return LTTCOMM_OK;
1926
1927 error:
1928 free(lus);
1929 return ret;
1930 }
1931
1932 /*
1933 * Create a kernel tracer session then create the default channel.
1934 */
1935 static int create_kernel_session(struct ltt_session *session)
1936 {
1937 int ret;
1938
1939 DBG("Creating kernel session");
1940
1941 ret = kernel_create_session(session, kernel_tracer_fd);
1942 if (ret < 0) {
1943 ret = LTTCOMM_KERN_SESS_FAIL;
1944 goto error;
1945 }
1946
1947 /* Set kernel consumer socket fd */
1948 if (kconsumer_data.cmd_sock) {
1949 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1950 }
1951
1952 ret = run_as_mkdir_recursive(session->kernel_session->trace_path,
1953 S_IRWXU | S_IRWXG, session->uid, session->gid);
1954 if (ret < 0) {
1955 if (ret != -EEXIST) {
1956 ERR("Trace directory creation error");
1957 goto error;
1958 }
1959 }
1960 session->kernel_session->uid = session->uid;
1961 session->kernel_session->gid = session->gid;
1962
1963 error:
1964 return ret;
1965 }
1966
1967 /*
1968 * Check if the UID or GID match the session. Root user has access to all
1969 * sessions.
1970 */
1971 static int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid)
1972 {
1973 if (uid != session->uid && gid != session->gid && uid != 0) {
1974 return 0;
1975 } else {
1976 return 1;
1977 }
1978 }
1979
1980 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
1981 {
1982 unsigned int i = 0;
1983 struct ltt_session *session;
1984
1985 DBG("Counting number of available session for UID %d GID %d",
1986 uid, gid);
1987 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1988 /*
1989 * Only list the sessions the user can control.
1990 */
1991 if (!session_access_ok(session, uid, gid)) {
1992 continue;
1993 }
1994 i++;
1995 }
1996 return i;
1997 }
1998
1999 /*
2000 * Using the session list, filled a lttng_session array to send back to the
2001 * client for session listing.
2002 *
2003 * The session list lock MUST be acquired before calling this function. Use
2004 * session_lock_list() and session_unlock_list().
2005 */
2006 static void list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2007 gid_t gid)
2008 {
2009 unsigned int i = 0;
2010 struct ltt_session *session;
2011
2012 DBG("Getting all available session for UID %d GID %d",
2013 uid, gid);
2014 /*
2015 * Iterate over session list and append data after the control struct in
2016 * the buffer.
2017 */
2018 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2019 /*
2020 * Only list the sessions the user can control.
2021 */
2022 if (!session_access_ok(session, uid, gid)) {
2023 continue;
2024 }
2025 strncpy(sessions[i].path, session->path, PATH_MAX);
2026 sessions[i].path[PATH_MAX - 1] = '\0';
2027 strncpy(sessions[i].name, session->name, NAME_MAX);
2028 sessions[i].name[NAME_MAX - 1] = '\0';
2029 sessions[i].enabled = session->enabled;
2030 i++;
2031 }
2032 }
2033
2034 /*
2035 * Fill lttng_channel array of all channels.
2036 */
2037 static void list_lttng_channels(int domain, struct ltt_session *session,
2038 struct lttng_channel *channels)
2039 {
2040 int i = 0;
2041 struct ltt_kernel_channel *kchan;
2042
2043 DBG("Listing channels for session %s", session->name);
2044
2045 switch (domain) {
2046 case LTTNG_DOMAIN_KERNEL:
2047 /* Kernel channels */
2048 if (session->kernel_session != NULL) {
2049 cds_list_for_each_entry(kchan,
2050 &session->kernel_session->channel_list.head, list) {
2051 /* Copy lttng_channel struct to array */
2052 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2053 channels[i].enabled = kchan->enabled;
2054 i++;
2055 }
2056 }
2057 break;
2058 case LTTNG_DOMAIN_UST:
2059 {
2060 struct lttng_ht_iter iter;
2061 struct ltt_ust_channel *uchan;
2062
2063 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
2064 &iter.iter, uchan, node.node) {
2065 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2066 channels[i].attr.overwrite = uchan->attr.overwrite;
2067 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2068 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2069 channels[i].attr.switch_timer_interval =
2070 uchan->attr.switch_timer_interval;
2071 channels[i].attr.read_timer_interval =
2072 uchan->attr.read_timer_interval;
2073 channels[i].enabled = uchan->enabled;
2074 switch (uchan->attr.output) {
2075 case LTTNG_UST_MMAP:
2076 default:
2077 channels[i].attr.output = LTTNG_EVENT_MMAP;
2078 break;
2079 }
2080 i++;
2081 }
2082 break;
2083 }
2084 default:
2085 break;
2086 }
2087 }
2088
2089 /*
2090 * Create a list of ust global domain events.
2091 */
2092 static int list_lttng_ust_global_events(char *channel_name,
2093 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2094 {
2095 int i = 0, ret = 0;
2096 unsigned int nb_event = 0;
2097 struct lttng_ht_iter iter;
2098 struct lttng_ht_node_str *node;
2099 struct ltt_ust_channel *uchan;
2100 struct ltt_ust_event *uevent;
2101 struct lttng_event *tmp;
2102
2103 DBG("Listing UST global events for channel %s", channel_name);
2104
2105 rcu_read_lock();
2106
2107 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2108 node = lttng_ht_iter_get_node_str(&iter);
2109 if (node == NULL) {
2110 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2111 goto error;
2112 }
2113
2114 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2115
2116 nb_event += lttng_ht_get_count(uchan->events);
2117
2118 if (nb_event == 0) {
2119 ret = nb_event;
2120 goto error;
2121 }
2122
2123 DBG3("Listing UST global %d events", nb_event);
2124
2125 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2126 if (tmp == NULL) {
2127 ret = -LTTCOMM_FATAL;
2128 goto error;
2129 }
2130
2131 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2132 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2133 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2134 tmp[i].enabled = uevent->enabled;
2135 switch (uevent->attr.instrumentation) {
2136 case LTTNG_UST_TRACEPOINT:
2137 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2138 break;
2139 case LTTNG_UST_PROBE:
2140 tmp[i].type = LTTNG_EVENT_PROBE;
2141 break;
2142 case LTTNG_UST_FUNCTION:
2143 tmp[i].type = LTTNG_EVENT_FUNCTION;
2144 break;
2145 case LTTNG_UST_TRACEPOINT_LOGLEVEL:
2146 tmp[i].type = LTTNG_EVENT_TRACEPOINT_LOGLEVEL;
2147 break;
2148 }
2149 i++;
2150 }
2151
2152 ret = nb_event;
2153 *events = tmp;
2154
2155 error:
2156 rcu_read_unlock();
2157 return ret;
2158 }
2159
2160 /*
2161 * Fill lttng_event array of all kernel events in the channel.
2162 */
2163 static int list_lttng_kernel_events(char *channel_name,
2164 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2165 {
2166 int i = 0, ret;
2167 unsigned int nb_event;
2168 struct ltt_kernel_event *event;
2169 struct ltt_kernel_channel *kchan;
2170
2171 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2172 if (kchan == NULL) {
2173 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2174 goto error;
2175 }
2176
2177 nb_event = kchan->event_count;
2178
2179 DBG("Listing events for channel %s", kchan->channel->name);
2180
2181 if (nb_event == 0) {
2182 ret = nb_event;
2183 goto error;
2184 }
2185
2186 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2187 if (*events == NULL) {
2188 ret = LTTCOMM_FATAL;
2189 goto error;
2190 }
2191
2192 /* Kernel channels */
2193 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2194 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2195 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2196 (*events)[i].enabled = event->enabled;
2197 switch (event->event->instrumentation) {
2198 case LTTNG_KERNEL_TRACEPOINT:
2199 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2200 break;
2201 case LTTNG_KERNEL_KPROBE:
2202 case LTTNG_KERNEL_KRETPROBE:
2203 (*events)[i].type = LTTNG_EVENT_PROBE;
2204 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2205 sizeof(struct lttng_kernel_kprobe));
2206 break;
2207 case LTTNG_KERNEL_FUNCTION:
2208 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2209 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2210 sizeof(struct lttng_kernel_function));
2211 break;
2212 case LTTNG_KERNEL_NOOP:
2213 (*events)[i].type = LTTNG_EVENT_NOOP;
2214 break;
2215 case LTTNG_KERNEL_SYSCALL:
2216 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2217 break;
2218 case LTTNG_KERNEL_ALL:
2219 assert(0);
2220 break;
2221 }
2222 i++;
2223 }
2224
2225 return nb_event;
2226
2227 error:
2228 return ret;
2229 }
2230
2231 /*
2232 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2233 */
2234 static int cmd_disable_channel(struct ltt_session *session,
2235 int domain, char *channel_name)
2236 {
2237 int ret;
2238 struct ltt_ust_session *usess;
2239
2240 usess = session->ust_session;
2241
2242 switch (domain) {
2243 case LTTNG_DOMAIN_KERNEL:
2244 {
2245 ret = channel_kernel_disable(session->kernel_session,
2246 channel_name);
2247 if (ret != LTTCOMM_OK) {
2248 goto error;
2249 }
2250
2251 kernel_wait_quiescent(kernel_tracer_fd);
2252 break;
2253 }
2254 case LTTNG_DOMAIN_UST:
2255 {
2256 struct ltt_ust_channel *uchan;
2257 struct lttng_ht *chan_ht;
2258
2259 chan_ht = usess->domain_global.channels;
2260
2261 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2262 if (uchan == NULL) {
2263 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2264 goto error;
2265 }
2266
2267 ret = channel_ust_disable(usess, domain, uchan);
2268 if (ret != LTTCOMM_OK) {
2269 goto error;
2270 }
2271 break;
2272 }
2273 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2274 case LTTNG_DOMAIN_UST_EXEC_NAME:
2275 case LTTNG_DOMAIN_UST_PID:
2276 ret = LTTCOMM_NOT_IMPLEMENTED;
2277 goto error;
2278 default:
2279 ret = LTTCOMM_UNKNOWN_DOMAIN;
2280 goto error;
2281 }
2282
2283 ret = LTTCOMM_OK;
2284
2285 error:
2286 return ret;
2287 }
2288
2289 /*
2290 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2291 */
2292 static int cmd_enable_channel(struct ltt_session *session,
2293 int domain, struct lttng_channel *attr)
2294 {
2295 int ret;
2296 struct ltt_ust_session *usess = session->ust_session;
2297 struct lttng_ht *chan_ht;
2298
2299 DBG("Enabling channel %s for session %s", attr->name, session->name);
2300
2301 switch (domain) {
2302 case LTTNG_DOMAIN_KERNEL:
2303 {
2304 struct ltt_kernel_channel *kchan;
2305
2306 kchan = trace_kernel_get_channel_by_name(attr->name,
2307 session->kernel_session);
2308 if (kchan == NULL) {
2309 ret = channel_kernel_create(session->kernel_session,
2310 attr, kernel_poll_pipe[1]);
2311 } else {
2312 ret = channel_kernel_enable(session->kernel_session, kchan);
2313 }
2314
2315 if (ret != LTTCOMM_OK) {
2316 goto error;
2317 }
2318
2319 kernel_wait_quiescent(kernel_tracer_fd);
2320 break;
2321 }
2322 case LTTNG_DOMAIN_UST:
2323 {
2324 struct ltt_ust_channel *uchan;
2325
2326 chan_ht = usess->domain_global.channels;
2327
2328 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2329 if (uchan == NULL) {
2330 ret = channel_ust_create(usess, domain, attr);
2331 } else {
2332 ret = channel_ust_enable(usess, domain, uchan);
2333 }
2334 break;
2335 }
2336 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2337 case LTTNG_DOMAIN_UST_EXEC_NAME:
2338 case LTTNG_DOMAIN_UST_PID:
2339 ret = LTTCOMM_NOT_IMPLEMENTED;
2340 goto error;
2341 default:
2342 ret = LTTCOMM_UNKNOWN_DOMAIN;
2343 goto error;
2344 }
2345
2346 error:
2347 return ret;
2348 }
2349
2350 /*
2351 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2352 */
2353 static int cmd_disable_event(struct ltt_session *session, int domain,
2354 char *channel_name, char *event_name)
2355 {
2356 int ret;
2357
2358 switch (domain) {
2359 case LTTNG_DOMAIN_KERNEL:
2360 {
2361 struct ltt_kernel_channel *kchan;
2362 struct ltt_kernel_session *ksess;
2363
2364 ksess = session->kernel_session;
2365
2366 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2367 if (kchan == NULL) {
2368 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2369 goto error;
2370 }
2371
2372 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2373 if (ret != LTTCOMM_OK) {
2374 goto error;
2375 }
2376
2377 kernel_wait_quiescent(kernel_tracer_fd);
2378 break;
2379 }
2380 case LTTNG_DOMAIN_UST:
2381 {
2382 struct ltt_ust_channel *uchan;
2383 struct ltt_ust_session *usess;
2384
2385 usess = session->ust_session;
2386
2387 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2388 channel_name);
2389 if (uchan == NULL) {
2390 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2391 goto error;
2392 }
2393
2394 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2395 if (ret != LTTCOMM_OK) {
2396 goto error;
2397 }
2398
2399 DBG3("Disable UST event %s in channel %s completed", event_name,
2400 channel_name);
2401 break;
2402 }
2403 case LTTNG_DOMAIN_UST_EXEC_NAME:
2404 case LTTNG_DOMAIN_UST_PID:
2405 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2406 default:
2407 ret = LTTCOMM_NOT_IMPLEMENTED;
2408 goto error;
2409 }
2410
2411 ret = LTTCOMM_OK;
2412
2413 error:
2414 return ret;
2415 }
2416
2417 /*
2418 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2419 */
2420 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2421 char *channel_name)
2422 {
2423 int ret;
2424
2425 switch (domain) {
2426 case LTTNG_DOMAIN_KERNEL:
2427 {
2428 struct ltt_kernel_session *ksess;
2429 struct ltt_kernel_channel *kchan;
2430
2431 ksess = session->kernel_session;
2432
2433 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2434 if (kchan == NULL) {
2435 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2436 goto error;
2437 }
2438
2439 ret = event_kernel_disable_all(ksess, kchan);
2440 if (ret != LTTCOMM_OK) {
2441 goto error;
2442 }
2443
2444 kernel_wait_quiescent(kernel_tracer_fd);
2445 break;
2446 }
2447 case LTTNG_DOMAIN_UST:
2448 {
2449 struct ltt_ust_session *usess;
2450 struct ltt_ust_channel *uchan;
2451
2452 usess = session->ust_session;
2453
2454 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2455 channel_name);
2456 if (uchan == NULL) {
2457 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2458 goto error;
2459 }
2460
2461 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2462 if (ret != 0) {
2463 goto error;
2464 }
2465
2466 DBG3("Disable all UST events in channel %s completed", channel_name);
2467
2468 break;
2469 }
2470 case LTTNG_DOMAIN_UST_EXEC_NAME:
2471 case LTTNG_DOMAIN_UST_PID:
2472 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2473 default:
2474 ret = LTTCOMM_NOT_IMPLEMENTED;
2475 goto error;
2476 }
2477
2478 ret = LTTCOMM_OK;
2479
2480 error:
2481 return ret;
2482 }
2483
2484 /*
2485 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2486 */
2487 static int cmd_add_context(struct ltt_session *session, int domain,
2488 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2489 {
2490 int ret;
2491
2492 switch (domain) {
2493 case LTTNG_DOMAIN_KERNEL:
2494 /* Add kernel context to kernel tracer */
2495 ret = context_kernel_add(session->kernel_session, ctx,
2496 event_name, channel_name);
2497 if (ret != LTTCOMM_OK) {
2498 goto error;
2499 }
2500 break;
2501 case LTTNG_DOMAIN_UST:
2502 {
2503 struct ltt_ust_session *usess = session->ust_session;
2504
2505 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2506 if (ret != LTTCOMM_OK) {
2507 goto error;
2508 }
2509 break;
2510 }
2511 case LTTNG_DOMAIN_UST_EXEC_NAME:
2512 case LTTNG_DOMAIN_UST_PID:
2513 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2514 default:
2515 ret = LTTCOMM_NOT_IMPLEMENTED;
2516 goto error;
2517 }
2518
2519 ret = LTTCOMM_OK;
2520
2521 error:
2522 return ret;
2523 }
2524
2525 /*
2526 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2527 *
2528 * TODO: currently, both events and loglevels are kept within the same
2529 * namespace for UST global registry/app registery, so if an event
2530 * happen to have the same name as the loglevel (very unlikely though),
2531 * and an attempt is made to enable/disable both in the same session,
2532 * the first to be created will be the only one allowed to exist.
2533 */
2534 static int cmd_enable_event(struct ltt_session *session, int domain,
2535 char *channel_name, struct lttng_event *event)
2536 {
2537 int ret;
2538 struct lttng_channel *attr;
2539 struct ltt_ust_session *usess = session->ust_session;
2540
2541 switch (domain) {
2542 case LTTNG_DOMAIN_KERNEL:
2543 {
2544 struct ltt_kernel_channel *kchan;
2545
2546 kchan = trace_kernel_get_channel_by_name(channel_name,
2547 session->kernel_session);
2548 if (kchan == NULL) {
2549 attr = channel_new_default_attr(domain);
2550 if (attr == NULL) {
2551 ret = LTTCOMM_FATAL;
2552 goto error;
2553 }
2554 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2555
2556 /* This call will notify the kernel thread */
2557 ret = channel_kernel_create(session->kernel_session,
2558 attr, kernel_poll_pipe[1]);
2559 if (ret != LTTCOMM_OK) {
2560 free(attr);
2561 goto error;
2562 }
2563 free(attr);
2564 }
2565
2566 /* Get the newly created kernel channel pointer */
2567 kchan = trace_kernel_get_channel_by_name(channel_name,
2568 session->kernel_session);
2569 if (kchan == NULL) {
2570 /* This sould not happen... */
2571 ret = LTTCOMM_FATAL;
2572 goto error;
2573 }
2574
2575 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2576 event);
2577 if (ret != LTTCOMM_OK) {
2578 goto error;
2579 }
2580
2581 kernel_wait_quiescent(kernel_tracer_fd);
2582 break;
2583 }
2584 case LTTNG_DOMAIN_UST:
2585 {
2586 struct lttng_channel *attr;
2587 struct ltt_ust_channel *uchan;
2588
2589 /* Get channel from global UST domain */
2590 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2591 channel_name);
2592 if (uchan == NULL) {
2593 /* Create default channel */
2594 attr = channel_new_default_attr(domain);
2595 if (attr == NULL) {
2596 ret = LTTCOMM_FATAL;
2597 goto error;
2598 }
2599 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2600 attr->name[NAME_MAX - 1] = '\0';
2601
2602 ret = channel_ust_create(usess, domain, attr);
2603 if (ret != LTTCOMM_OK) {
2604 free(attr);
2605 goto error;
2606 }
2607 free(attr);
2608
2609 /* Get the newly created channel reference back */
2610 uchan = trace_ust_find_channel_by_name(
2611 usess->domain_global.channels, channel_name);
2612 if (uchan == NULL) {
2613 /* Something is really wrong */
2614 ret = LTTCOMM_FATAL;
2615 goto error;
2616 }
2617 }
2618
2619 /* At this point, the session and channel exist on the tracer */
2620 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2621 if (ret != LTTCOMM_OK) {
2622 goto error;
2623 }
2624 break;
2625 }
2626 case LTTNG_DOMAIN_UST_EXEC_NAME:
2627 case LTTNG_DOMAIN_UST_PID:
2628 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2629 default:
2630 ret = LTTCOMM_NOT_IMPLEMENTED;
2631 goto error;
2632 }
2633
2634 ret = LTTCOMM_OK;
2635
2636 error:
2637 return ret;
2638 }
2639
2640 /*
2641 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2642 */
2643 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2644 char *channel_name, int event_type)
2645 {
2646 int ret;
2647 struct ltt_kernel_channel *kchan;
2648
2649 switch (domain) {
2650 case LTTNG_DOMAIN_KERNEL:
2651 kchan = trace_kernel_get_channel_by_name(channel_name,
2652 session->kernel_session);
2653 if (kchan == NULL) {
2654 /* This call will notify the kernel thread */
2655 ret = channel_kernel_create(session->kernel_session, NULL,
2656 kernel_poll_pipe[1]);
2657 if (ret != LTTCOMM_OK) {
2658 goto error;
2659 }
2660
2661 /* Get the newly created kernel channel pointer */
2662 kchan = trace_kernel_get_channel_by_name(channel_name,
2663 session->kernel_session);
2664 if (kchan == NULL) {
2665 /* This sould not happen... */
2666 ret = LTTCOMM_FATAL;
2667 goto error;
2668 }
2669
2670 }
2671
2672 switch (event_type) {
2673 case LTTNG_EVENT_SYSCALL:
2674 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2675 kchan, kernel_tracer_fd);
2676 break;
2677 case LTTNG_EVENT_TRACEPOINT:
2678 /*
2679 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2680 * events already registered to the channel.
2681 */
2682 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2683 kchan, kernel_tracer_fd);
2684 break;
2685 case LTTNG_EVENT_ALL:
2686 /* Enable syscalls and tracepoints */
2687 ret = event_kernel_enable_all(session->kernel_session,
2688 kchan, kernel_tracer_fd);
2689 break;
2690 default:
2691 ret = LTTCOMM_KERN_ENABLE_FAIL;
2692 goto error;
2693 }
2694
2695 /* Manage return value */
2696 if (ret != LTTCOMM_OK) {
2697 goto error;
2698 }
2699
2700 kernel_wait_quiescent(kernel_tracer_fd);
2701 break;
2702 case LTTNG_DOMAIN_UST:
2703 {
2704 struct lttng_channel *attr;
2705 struct ltt_ust_channel *uchan;
2706 struct ltt_ust_session *usess = session->ust_session;
2707
2708 /* Get channel from global UST domain */
2709 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2710 channel_name);
2711 if (uchan == NULL) {
2712 /* Create default channel */
2713 attr = channel_new_default_attr(domain);
2714 if (attr == NULL) {
2715 ret = LTTCOMM_FATAL;
2716 goto error;
2717 }
2718 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2719 attr->name[NAME_MAX - 1] = '\0';
2720
2721 /* Use the internal command enable channel */
2722 ret = channel_ust_create(usess, domain, attr);
2723 if (ret != LTTCOMM_OK) {
2724 free(attr);
2725 goto error;
2726 }
2727 free(attr);
2728
2729 /* Get the newly created channel reference back */
2730 uchan = trace_ust_find_channel_by_name(
2731 usess->domain_global.channels, channel_name);
2732 if (uchan == NULL) {
2733 /* Something is really wrong */
2734 ret = LTTCOMM_FATAL;
2735 goto error;
2736 }
2737 }
2738
2739 /* At this point, the session and channel exist on the tracer */
2740
2741 switch (event_type) {
2742 case LTTNG_EVENT_ALL:
2743 case LTTNG_EVENT_TRACEPOINT:
2744 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2745 if (ret != LTTCOMM_OK) {
2746 goto error;
2747 }
2748 break;
2749 default:
2750 ret = LTTCOMM_UST_ENABLE_FAIL;
2751 goto error;
2752 }
2753
2754 /* Manage return value */
2755 if (ret != LTTCOMM_OK) {
2756 goto error;
2757 }
2758
2759 break;
2760 }
2761 case LTTNG_DOMAIN_UST_EXEC_NAME:
2762 case LTTNG_DOMAIN_UST_PID:
2763 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2764 default:
2765 ret = LTTCOMM_NOT_IMPLEMENTED;
2766 goto error;
2767 }
2768
2769 ret = LTTCOMM_OK;
2770
2771 error:
2772 return ret;
2773 }
2774
2775 /*
2776 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2777 */
2778 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2779 {
2780 int ret;
2781 ssize_t nb_events = 0;
2782
2783 switch (domain) {
2784 case LTTNG_DOMAIN_KERNEL:
2785 nb_events = kernel_list_events(kernel_tracer_fd, events);
2786 if (nb_events < 0) {
2787 ret = LTTCOMM_KERN_LIST_FAIL;
2788 goto error;
2789 }
2790 break;
2791 case LTTNG_DOMAIN_UST:
2792 nb_events = ust_app_list_events(events);
2793 if (nb_events < 0) {
2794 ret = LTTCOMM_UST_LIST_FAIL;
2795 goto error;
2796 }
2797 break;
2798 default:
2799 ret = LTTCOMM_NOT_IMPLEMENTED;
2800 goto error;
2801 }
2802
2803 return nb_events;
2804
2805 error:
2806 /* Return negative value to differentiate return code */
2807 return -ret;
2808 }
2809
2810 /*
2811 * Command LTTNG_START_TRACE processed by the client thread.
2812 */
2813 static int cmd_start_trace(struct ltt_session *session)
2814 {
2815 int ret;
2816 struct ltt_kernel_session *ksession;
2817 struct ltt_ust_session *usess;
2818
2819 /* Short cut */
2820 ksession = session->kernel_session;
2821 usess = session->ust_session;
2822
2823 if (session->enabled) {
2824 ret = LTTCOMM_UST_START_FAIL;
2825 goto error;
2826 }
2827
2828 session->enabled = 1;
2829
2830 /* Kernel tracing */
2831 if (ksession != NULL) {
2832 struct ltt_kernel_channel *kchan;
2833
2834 /* Open kernel metadata */
2835 if (ksession->metadata == NULL) {
2836 ret = kernel_open_metadata(ksession, ksession->trace_path);
2837 if (ret < 0) {
2838 ret = LTTCOMM_KERN_META_FAIL;
2839 goto error;
2840 }
2841 }
2842
2843 /* Open kernel metadata stream */
2844 if (ksession->metadata_stream_fd == 0) {
2845 ret = kernel_open_metadata_stream(ksession);
2846 if (ret < 0) {
2847 ERR("Kernel create metadata stream failed");
2848 ret = LTTCOMM_KERN_STREAM_FAIL;
2849 goto error;
2850 }
2851 }
2852
2853 /* For each channel */
2854 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2855 if (kchan->stream_count == 0) {
2856 ret = kernel_open_channel_stream(kchan);
2857 if (ret < 0) {
2858 ret = LTTCOMM_KERN_STREAM_FAIL;
2859 goto error;
2860 }
2861 /* Update the stream global counter */
2862 ksession->stream_count_global += ret;
2863 }
2864 }
2865
2866 /* Setup kernel consumer socket and send fds to it */
2867 ret = init_kernel_tracing(ksession);
2868 if (ret < 0) {
2869 ret = LTTCOMM_KERN_START_FAIL;
2870 goto error;
2871 }
2872
2873 /* This start the kernel tracing */
2874 ret = kernel_start_session(ksession);
2875 if (ret < 0) {
2876 ret = LTTCOMM_KERN_START_FAIL;
2877 goto error;
2878 }
2879
2880 /* Quiescent wait after starting trace */
2881 kernel_wait_quiescent(kernel_tracer_fd);
2882 }
2883
2884 /* Flag session that trace should start automatically */
2885 if (usess) {
2886 usess->start_trace = 1;
2887
2888 ret = ust_app_start_trace_all(usess);
2889 if (ret < 0) {
2890 ret = LTTCOMM_UST_START_FAIL;
2891 goto error;
2892 }
2893 }
2894
2895 ret = LTTCOMM_OK;
2896
2897 error:
2898 return ret;
2899 }
2900
2901 /*
2902 * Command LTTNG_STOP_TRACE processed by the client thread.
2903 */
2904 static int cmd_stop_trace(struct ltt_session *session)
2905 {
2906 int ret;
2907 struct ltt_kernel_channel *kchan;
2908 struct ltt_kernel_session *ksession;
2909 struct ltt_ust_session *usess;
2910
2911 /* Short cut */
2912 ksession = session->kernel_session;
2913 usess = session->ust_session;
2914
2915 if (!session->enabled) {
2916 ret = LTTCOMM_UST_STOP_FAIL;
2917 goto error;
2918 }
2919
2920 session->enabled = 0;
2921
2922 /* Kernel tracer */
2923 if (ksession != NULL) {
2924 DBG("Stop kernel tracing");
2925
2926 /* Flush all buffers before stopping */
2927 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2928 if (ret < 0) {
2929 ERR("Kernel metadata flush failed");
2930 }
2931
2932 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2933 ret = kernel_flush_buffer(kchan);
2934 if (ret < 0) {
2935 ERR("Kernel flush buffer error");
2936 }
2937 }
2938
2939 ret = kernel_stop_session(ksession);
2940 if (ret < 0) {
2941 ret = LTTCOMM_KERN_STOP_FAIL;
2942 goto error;
2943 }
2944
2945 kernel_wait_quiescent(kernel_tracer_fd);
2946 }
2947
2948 if (usess) {
2949 usess->start_trace = 0;
2950
2951 ret = ust_app_stop_trace_all(usess);
2952 if (ret < 0) {
2953 ret = LTTCOMM_UST_STOP_FAIL;
2954 goto error;
2955 }
2956 }
2957
2958 ret = LTTCOMM_OK;
2959
2960 error:
2961 return ret;
2962 }
2963
2964 /*
2965 * Command LTTNG_CREATE_SESSION processed by the client thread.
2966 */
2967 static int cmd_create_session(char *name, char *path, struct ucred *creds)
2968 {
2969 int ret;
2970
2971 ret = session_create(name, path, creds->uid, creds->gid);
2972 if (ret != LTTCOMM_OK) {
2973 goto error;
2974 }
2975
2976 ret = LTTCOMM_OK;
2977
2978 error:
2979 return ret;
2980 }
2981
2982 /*
2983 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2984 */
2985 static int cmd_destroy_session(struct ltt_session *session, char *name)
2986 {
2987 int ret;
2988
2989 /* Clean kernel session teardown */
2990 teardown_kernel_session(session);
2991 /* UST session teardown */
2992 teardown_ust_session(session);
2993
2994 /*
2995 * Must notify the kernel thread here to update it's poll setin order
2996 * to remove the channel(s)' fd just destroyed.
2997 */
2998 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2999 if (ret < 0) {
3000 perror("write kernel poll pipe");
3001 }
3002
3003 ret = session_destroy(session);
3004
3005 return ret;
3006 }
3007
3008 /*
3009 * Command LTTNG_CALIBRATE processed by the client thread.
3010 */
3011 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3012 {
3013 int ret;
3014
3015 switch (domain) {
3016 case LTTNG_DOMAIN_KERNEL:
3017 {
3018 struct lttng_kernel_calibrate kcalibrate;
3019
3020 kcalibrate.type = calibrate->type;
3021 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3022 if (ret < 0) {
3023 ret = LTTCOMM_KERN_ENABLE_FAIL;
3024 goto error;
3025 }
3026 break;
3027 }
3028 default:
3029 /* TODO: Userspace tracing */
3030 ret = LTTCOMM_NOT_IMPLEMENTED;
3031 goto error;
3032 }
3033
3034 ret = LTTCOMM_OK;
3035
3036 error:
3037 return ret;
3038 }
3039
3040 /*
3041 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3042 */
3043 static int cmd_register_consumer(struct ltt_session *session, int domain,
3044 char *sock_path)
3045 {
3046 int ret, sock;
3047
3048 switch (domain) {
3049 case LTTNG_DOMAIN_KERNEL:
3050 /* Can't register a consumer if there is already one */
3051 if (session->kernel_session->consumer_fds_sent != 0) {
3052 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3053 goto error;
3054 }
3055
3056 sock = lttcomm_connect_unix_sock(sock_path);
3057 if (sock < 0) {
3058 ret = LTTCOMM_CONNECT_FAIL;
3059 goto error;
3060 }
3061
3062 session->kernel_session->consumer_fd = sock;
3063 break;
3064 default:
3065 /* TODO: Userspace tracing */
3066 ret = LTTCOMM_NOT_IMPLEMENTED;
3067 goto error;
3068 }
3069
3070 ret = LTTCOMM_OK;
3071
3072 error:
3073 return ret;
3074 }
3075
3076 /*
3077 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3078 */
3079 static ssize_t cmd_list_domains(struct ltt_session *session,
3080 struct lttng_domain **domains)
3081 {
3082 int ret, index = 0;
3083 ssize_t nb_dom = 0;
3084
3085 if (session->kernel_session != NULL) {
3086 DBG3("Listing domains found kernel domain");
3087 nb_dom++;
3088 }
3089
3090 if (session->ust_session != NULL) {
3091 DBG3("Listing domains found UST global domain");
3092 nb_dom++;
3093 }
3094
3095 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3096 if (*domains == NULL) {
3097 ret = -LTTCOMM_FATAL;
3098 goto error;
3099 }
3100
3101 if (session->kernel_session != NULL) {
3102 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3103 index++;
3104 }
3105
3106 if (session->ust_session != NULL) {
3107 (*domains)[index].type = LTTNG_DOMAIN_UST;
3108 index++;
3109 }
3110
3111 return nb_dom;
3112
3113 error:
3114 return ret;
3115 }
3116
3117 /*
3118 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3119 */
3120 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3121 struct lttng_channel **channels)
3122 {
3123 int ret;
3124 ssize_t nb_chan = 0;
3125
3126 switch (domain) {
3127 case LTTNG_DOMAIN_KERNEL:
3128 if (session->kernel_session != NULL) {
3129 nb_chan = session->kernel_session->channel_count;
3130 }
3131 DBG3("Number of kernel channels %zd", nb_chan);
3132 break;
3133 case LTTNG_DOMAIN_UST:
3134 if (session->ust_session != NULL) {
3135 nb_chan = lttng_ht_get_count(
3136 session->ust_session->domain_global.channels);
3137 }
3138 DBG3("Number of UST global channels %zd", nb_chan);
3139 break;
3140 default:
3141 *channels = NULL;
3142 ret = -LTTCOMM_NOT_IMPLEMENTED;
3143 goto error;
3144 }
3145
3146 if (nb_chan > 0) {
3147 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3148 if (*channels == NULL) {
3149 ret = -LTTCOMM_FATAL;
3150 goto error;
3151 }
3152
3153 list_lttng_channels(domain, session, *channels);
3154 } else {
3155 *channels = NULL;
3156 }
3157
3158 return nb_chan;
3159
3160 error:
3161 return ret;
3162 }
3163
3164 /*
3165 * Command LTTNG_LIST_EVENTS processed by the client thread.
3166 */
3167 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3168 char *channel_name, struct lttng_event **events)
3169 {
3170 int ret = 0;
3171 ssize_t nb_event = 0;
3172
3173 switch (domain) {
3174 case LTTNG_DOMAIN_KERNEL:
3175 if (session->kernel_session != NULL) {
3176 nb_event = list_lttng_kernel_events(channel_name,
3177 session->kernel_session, events);
3178 }
3179 break;
3180 case LTTNG_DOMAIN_UST:
3181 {
3182 if (session->ust_session != NULL) {
3183 nb_event = list_lttng_ust_global_events(channel_name,
3184 &session->ust_session->domain_global, events);
3185 }
3186 break;
3187 }
3188 default:
3189 ret = -LTTCOMM_NOT_IMPLEMENTED;
3190 goto error;
3191 }
3192
3193 ret = nb_event;
3194
3195 error:
3196 return ret;
3197 }
3198
3199 /*
3200 * Process the command requested by the lttng client within the command
3201 * context structure. This function make sure that the return structure (llm)
3202 * is set and ready for transmission before returning.
3203 *
3204 * Return any error encountered or 0 for success.
3205 */
3206 static int process_client_msg(struct command_ctx *cmd_ctx)
3207 {
3208 int ret = LTTCOMM_OK;
3209 int need_tracing_session = 1;
3210
3211 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3212
3213 if (opt_no_kernel && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
3214 ret = LTTCOMM_KERN_NA;
3215 goto error;
3216 }
3217
3218 /*
3219 * Check for command that don't needs to allocate a returned payload. We do
3220 * this here so we don't have to make the call for no payload at each
3221 * command.
3222 */
3223 switch(cmd_ctx->lsm->cmd_type) {
3224 case LTTNG_LIST_SESSIONS:
3225 case LTTNG_LIST_TRACEPOINTS:
3226 case LTTNG_LIST_DOMAINS:
3227 case LTTNG_LIST_CHANNELS:
3228 case LTTNG_LIST_EVENTS:
3229 break;
3230 default:
3231 /* Setup lttng message with no payload */
3232 ret = setup_lttng_msg(cmd_ctx, 0);
3233 if (ret < 0) {
3234 /* This label does not try to unlock the session */
3235 goto init_setup_error;
3236 }
3237 }
3238
3239 /* Commands that DO NOT need a session. */
3240 switch (cmd_ctx->lsm->cmd_type) {
3241 case LTTNG_CALIBRATE:
3242 case LTTNG_CREATE_SESSION:
3243 case LTTNG_LIST_SESSIONS:
3244 case LTTNG_LIST_TRACEPOINTS:
3245 need_tracing_session = 0;
3246 break;
3247 default:
3248 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3249 session_lock_list();
3250 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3251 session_unlock_list();
3252 if (cmd_ctx->session == NULL) {
3253 if (cmd_ctx->lsm->session.name != NULL) {
3254 ret = LTTCOMM_SESS_NOT_FOUND;
3255 } else {
3256 /* If no session name specified */
3257 ret = LTTCOMM_SELECT_SESS;
3258 }
3259 goto error;
3260 } else {
3261 /* Acquire lock for the session */
3262 session_lock(cmd_ctx->session);
3263 }
3264 break;
3265 }
3266
3267 /*
3268 * Check domain type for specific "pre-action".
3269 */
3270 switch (cmd_ctx->lsm->domain.type) {
3271 case LTTNG_DOMAIN_KERNEL:
3272 if (!is_root) {
3273 ret = LTTCOMM_KERN_NA;
3274 goto error;
3275 }
3276
3277 /* Kernel tracer check */
3278 if (kernel_tracer_fd == 0) {
3279 /* Basically, load kernel tracer modules */
3280 init_kernel_tracer();
3281 if (kernel_tracer_fd == 0) {
3282 ret = LTTCOMM_KERN_NA;
3283 goto error;
3284 }
3285 }
3286
3287 /* Need a session for kernel command */
3288 if (need_tracing_session) {
3289 if (cmd_ctx->session->kernel_session == NULL) {
3290 ret = create_kernel_session(cmd_ctx->session);
3291 if (ret < 0) {
3292 ret = LTTCOMM_KERN_SESS_FAIL;
3293 goto error;
3294 }
3295 }
3296
3297 /* Start the kernel consumer daemon */
3298 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3299 if (kconsumer_data.pid == 0 &&
3300 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3301 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3302 ret = start_consumerd(&kconsumer_data);
3303 if (ret < 0) {
3304 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3305 goto error;
3306 }
3307 } else {
3308 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3309 }
3310 }
3311 break;
3312 case LTTNG_DOMAIN_UST:
3313 {
3314 if (need_tracing_session) {
3315 if (cmd_ctx->session->ust_session == NULL) {
3316 ret = create_ust_session(cmd_ctx->session,
3317 &cmd_ctx->lsm->domain);
3318 if (ret != LTTCOMM_OK) {
3319 goto error;
3320 }
3321 }
3322 /* Start the UST consumer daemons */
3323 /* 64-bit */
3324 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3325 if (consumerd64_bin[0] != '\0' &&
3326 ustconsumer64_data.pid == 0 &&
3327 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3328 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3329 ret = start_consumerd(&ustconsumer64_data);
3330 if (ret < 0) {
3331 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3332 ust_consumerd64_fd = -EINVAL;
3333 goto error;
3334 }
3335
3336 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3337 } else {
3338 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3339 }
3340 /* 32-bit */
3341 if (consumerd32_bin[0] != '\0' &&
3342 ustconsumer32_data.pid == 0 &&
3343 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3344 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3345 ret = start_consumerd(&ustconsumer32_data);
3346 if (ret < 0) {
3347 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3348 ust_consumerd32_fd = -EINVAL;
3349 goto error;
3350 }
3351 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3352 } else {
3353 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3354 }
3355 }
3356 break;
3357 }
3358 default:
3359 break;
3360 }
3361
3362 /*
3363 * Check that the UID or GID match that of the tracing session.
3364 * The root user can interact with all sessions.
3365 */
3366 if (need_tracing_session) {
3367 if (!session_access_ok(cmd_ctx->session,
3368 cmd_ctx->creds.uid, cmd_ctx->creds.gid)) {
3369 ret = LTTCOMM_EPERM;
3370 goto error;
3371 }
3372 }
3373
3374 /* Process by command type */
3375 switch (cmd_ctx->lsm->cmd_type) {
3376 case LTTNG_ADD_CONTEXT:
3377 {
3378 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3379 cmd_ctx->lsm->u.context.channel_name,
3380 cmd_ctx->lsm->u.context.event_name,
3381 &cmd_ctx->lsm->u.context.ctx);
3382 break;
3383 }
3384 case LTTNG_DISABLE_CHANNEL:
3385 {
3386 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3387 cmd_ctx->lsm->u.disable.channel_name);
3388 break;
3389 }
3390 case LTTNG_DISABLE_EVENT:
3391 {
3392 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3393 cmd_ctx->lsm->u.disable.channel_name,
3394 cmd_ctx->lsm->u.disable.name);
3395 ret = LTTCOMM_OK;
3396 break;
3397 }
3398 case LTTNG_DISABLE_ALL_EVENT:
3399 {
3400 DBG("Disabling all events");
3401
3402 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3403 cmd_ctx->lsm->u.disable.channel_name);
3404 break;
3405 }
3406 case LTTNG_ENABLE_CHANNEL:
3407 {
3408 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3409 &cmd_ctx->lsm->u.channel.chan);
3410 break;
3411 }
3412 case LTTNG_ENABLE_EVENT:
3413 {
3414 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3415 cmd_ctx->lsm->u.enable.channel_name,
3416 &cmd_ctx->lsm->u.enable.event);
3417 break;
3418 }
3419 case LTTNG_ENABLE_ALL_EVENT:
3420 {
3421 DBG("Enabling all events");
3422
3423 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3424 cmd_ctx->lsm->u.enable.channel_name,
3425 cmd_ctx->lsm->u.enable.event.type);
3426 break;
3427 }
3428 case LTTNG_LIST_TRACEPOINTS:
3429 {
3430 struct lttng_event *events;
3431 ssize_t nb_events;
3432
3433 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3434 if (nb_events < 0) {
3435 ret = -nb_events;
3436 goto error;
3437 }
3438
3439 /*
3440 * Setup lttng message with payload size set to the event list size in
3441 * bytes and then copy list into the llm payload.
3442 */
3443 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3444 if (ret < 0) {
3445 free(events);
3446 goto setup_error;
3447 }
3448
3449 /* Copy event list into message payload */
3450 memcpy(cmd_ctx->llm->payload, events,
3451 sizeof(struct lttng_event) * nb_events);
3452
3453 free(events);
3454
3455 ret = LTTCOMM_OK;
3456 break;
3457 }
3458 case LTTNG_START_TRACE:
3459 {
3460 ret = cmd_start_trace(cmd_ctx->session);
3461 break;
3462 }
3463 case LTTNG_STOP_TRACE:
3464 {
3465 ret = cmd_stop_trace(cmd_ctx->session);
3466 break;
3467 }
3468 case LTTNG_CREATE_SESSION:
3469 {
3470 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3471 cmd_ctx->lsm->session.path, &cmd_ctx->creds);
3472 break;
3473 }
3474 case LTTNG_DESTROY_SESSION:
3475 {
3476 ret = cmd_destroy_session(cmd_ctx->session,
3477 cmd_ctx->lsm->session.name);
3478 break;
3479 }
3480 case LTTNG_LIST_DOMAINS:
3481 {
3482 ssize_t nb_dom;
3483 struct lttng_domain *domains;
3484
3485 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3486 if (nb_dom < 0) {
3487 ret = -nb_dom;
3488 goto error;
3489 }
3490
3491 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3492 if (ret < 0) {
3493 goto setup_error;
3494 }
3495
3496 /* Copy event list into message payload */
3497 memcpy(cmd_ctx->llm->payload, domains,
3498 nb_dom * sizeof(struct lttng_domain));
3499
3500 free(domains);
3501
3502 ret = LTTCOMM_OK;
3503 break;
3504 }
3505 case LTTNG_LIST_CHANNELS:
3506 {
3507 size_t nb_chan;
3508 struct lttng_channel *channels;
3509
3510 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
3511 cmd_ctx->session, &channels);
3512 if (nb_chan < 0) {
3513 ret = -nb_chan;
3514 goto error;
3515 }
3516
3517 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3518 if (ret < 0) {
3519 goto setup_error;
3520 }
3521
3522 /* Copy event list into message payload */
3523 memcpy(cmd_ctx->llm->payload, channels,
3524 nb_chan * sizeof(struct lttng_channel));
3525
3526 free(channels);
3527
3528 ret = LTTCOMM_OK;
3529 break;
3530 }
3531 case LTTNG_LIST_EVENTS:
3532 {
3533 ssize_t nb_event;
3534 struct lttng_event *events = NULL;
3535
3536 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
3537 cmd_ctx->lsm->u.list.channel_name, &events);
3538 if (nb_event < 0) {
3539 ret = -nb_event;
3540 goto error;
3541 }
3542
3543 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3544 if (ret < 0) {
3545 goto setup_error;
3546 }
3547
3548 /* Copy event list into message payload */
3549 memcpy(cmd_ctx->llm->payload, events,
3550 nb_event * sizeof(struct lttng_event));
3551
3552 free(events);
3553
3554 ret = LTTCOMM_OK;
3555 break;
3556 }
3557 case LTTNG_LIST_SESSIONS:
3558 {
3559 unsigned int nr_sessions;
3560
3561 session_lock_list();
3562 nr_sessions = lttng_sessions_count(cmd_ctx->creds.uid, cmd_ctx->creds.gid);
3563 if (nr_sessions == 0) {
3564 ret = LTTCOMM_NO_SESSION;
3565 session_unlock_list();
3566 goto error;
3567 }
3568 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * nr_sessions);
3569 if (ret < 0) {
3570 session_unlock_list();
3571 goto setup_error;
3572 }
3573
3574 /* Filled the session array */
3575 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload),
3576 cmd_ctx->creds.uid, cmd_ctx->creds.gid);
3577
3578 session_unlock_list();
3579
3580 ret = LTTCOMM_OK;
3581 break;
3582 }
3583 case LTTNG_CALIBRATE:
3584 {
3585 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3586 &cmd_ctx->lsm->u.calibrate);
3587 break;
3588 }
3589 case LTTNG_REGISTER_CONSUMER:
3590 {
3591 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3592 cmd_ctx->lsm->u.reg.path);
3593 break;
3594 }
3595 default:
3596 ret = LTTCOMM_UND;
3597 break;
3598 }
3599
3600 error:
3601 if (cmd_ctx->llm == NULL) {
3602 DBG("Missing llm structure. Allocating one.");
3603 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3604 goto setup_error;
3605 }
3606 }
3607 /* Set return code */
3608 cmd_ctx->llm->ret_code = ret;
3609 setup_error:
3610 if (cmd_ctx->session) {
3611 session_unlock(cmd_ctx->session);
3612 }
3613 init_setup_error:
3614 return ret;
3615 }
3616
3617 /*
3618 * This thread manage all clients request using the unix client socket for
3619 * communication.
3620 */
3621 static void *thread_manage_clients(void *data)
3622 {
3623 int sock = 0, ret, i, pollfd;
3624 uint32_t revents, nb_fd;
3625 struct command_ctx *cmd_ctx = NULL;
3626 struct lttng_poll_event events;
3627
3628 DBG("[thread] Manage client started");
3629
3630 rcu_register_thread();
3631
3632 ret = lttcomm_listen_unix_sock(client_sock);
3633 if (ret < 0) {
3634 goto error;
3635 }
3636
3637 /*
3638 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3639 * more will be added to this poll set.
3640 */
3641 ret = create_thread_poll_set(&events, 2);
3642 if (ret < 0) {
3643 goto error;
3644 }
3645
3646 /* Add the application registration socket */
3647 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3648 if (ret < 0) {
3649 goto error;
3650 }
3651
3652 /*
3653 * Notify parent pid that we are ready to accept command for client side.
3654 */
3655 if (opt_sig_parent) {
3656 kill(ppid, SIGCHLD);
3657 }
3658
3659 while (1) {
3660 DBG("Accepting client command ...");
3661
3662 nb_fd = LTTNG_POLL_GETNB(&events);
3663
3664 /* Inifinite blocking call, waiting for transmission */
3665 ret = lttng_poll_wait(&events, -1);
3666 if (ret < 0) {
3667 goto error;
3668 }
3669
3670 for (i = 0; i < nb_fd; i++) {
3671 /* Fetch once the poll data */
3672 revents = LTTNG_POLL_GETEV(&events, i);
3673 pollfd = LTTNG_POLL_GETFD(&events, i);
3674
3675 /* Thread quit pipe has been closed. Killing thread. */
3676 ret = check_thread_quit_pipe(pollfd, revents);
3677 if (ret) {
3678 goto error;
3679 }
3680
3681 /* Event on the registration socket */
3682 if (pollfd == client_sock) {
3683 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3684 ERR("Client socket poll error");
3685 goto error;
3686 }
3687 }
3688 }
3689
3690 DBG("Wait for client response");
3691
3692 sock = lttcomm_accept_unix_sock(client_sock);
3693 if (sock < 0) {
3694 goto error;
3695 }
3696
3697 /* Set socket option for credentials retrieval */
3698 ret = lttcomm_setsockopt_creds_unix_sock(sock);
3699 if (ret < 0) {
3700 goto error;
3701 }
3702
3703 /* Allocate context command to process the client request */
3704 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3705 if (cmd_ctx == NULL) {
3706 perror("zmalloc cmd_ctx");
3707 goto error;
3708 }
3709
3710 /* Allocate data buffer for reception */
3711 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3712 if (cmd_ctx->lsm == NULL) {
3713 perror("zmalloc cmd_ctx->lsm");
3714 goto error;
3715 }
3716
3717 cmd_ctx->llm = NULL;
3718 cmd_ctx->session = NULL;
3719
3720 /*
3721 * Data is received from the lttng client. The struct
3722 * lttcomm_session_msg (lsm) contains the command and data request of
3723 * the client.
3724 */
3725 DBG("Receiving data from client ...");
3726 ret = lttcomm_recv_creds_unix_sock(sock, cmd_ctx->lsm,
3727 sizeof(struct lttcomm_session_msg), &cmd_ctx->creds);
3728 if (ret <= 0) {
3729 DBG("Nothing recv() from client... continuing");
3730 close(sock);
3731 free(cmd_ctx);
3732 continue;
3733 }
3734
3735 // TODO: Validate cmd_ctx including sanity check for
3736 // security purpose.
3737
3738 rcu_thread_online();
3739 /*
3740 * This function dispatch the work to the kernel or userspace tracer
3741 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3742 * informations for the client. The command context struct contains
3743 * everything this function may needs.
3744 */
3745 ret = process_client_msg(cmd_ctx);
3746 rcu_thread_offline();
3747 if (ret < 0) {
3748 /*
3749 * TODO: Inform client somehow of the fatal error. At
3750 * this point, ret < 0 means that a zmalloc failed
3751 * (ENOMEM). Error detected but still accept command.
3752 */
3753 clean_command_ctx(&cmd_ctx);
3754 continue;
3755 }
3756
3757 DBG("Sending response (size: %d, retcode: %s)",
3758 cmd_ctx->lttng_msg_size,
3759 lttng_strerror(-cmd_ctx->llm->ret_code));
3760 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3761 if (ret < 0) {
3762 ERR("Failed to send data back to client");
3763 }
3764
3765 /* End of transmission */
3766 close(sock);
3767
3768 clean_command_ctx(&cmd_ctx);
3769 }
3770
3771 error:
3772 DBG("Client thread dying");
3773 unlink(client_unix_sock_path);
3774 close(client_sock);
3775 close(sock);
3776
3777 lttng_poll_clean(&events);
3778 clean_command_ctx(&cmd_ctx);
3779
3780 rcu_unregister_thread();
3781 return NULL;
3782 }
3783
3784
3785 /*
3786 * usage function on stderr
3787 */
3788 static void usage(void)
3789 {
3790 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3791 fprintf(stderr, " -h, --help Display this usage.\n");
3792 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3793 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3794 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3795 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3796 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
3797 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
3798 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
3799 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
3800 fprintf(stderr, " --consumerd32-path PATH Specify path for the 32-bit UST consumer daemon binary\n");
3801 fprintf(stderr, " --consumerd32-libdir PATH Specify path for the 32-bit UST consumer daemon libraries\n");
3802 fprintf(stderr, " --consumerd64-path PATH Specify path for the 64-bit UST consumer daemon binary\n");
3803 fprintf(stderr, " --consumerd64-libdir PATH Specify path for the 64-bit UST consumer daemon libraries\n");
3804 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3805 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3806 fprintf(stderr, " -V, --version Show version number.\n");
3807 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3808 fprintf(stderr, " -q, --quiet No output at all.\n");
3809 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3810 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3811 fprintf(stderr, " --no-kernel Disable kernel tracer\n");
3812 }
3813
3814 /*
3815 * daemon argument parsing
3816 */
3817 static int parse_args(int argc, char **argv)
3818 {
3819 int c;
3820
3821 static struct option long_options[] = {
3822 { "client-sock", 1, 0, 'c' },
3823 { "apps-sock", 1, 0, 'a' },
3824 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3825 { "kconsumerd-err-sock", 1, 0, 'E' },
3826 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
3827 { "ustconsumerd32-err-sock", 1, 0, 'H' },
3828 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
3829 { "ustconsumerd64-err-sock", 1, 0, 'F' },
3830 { "consumerd32-path", 1, 0, 'u' },
3831 { "consumerd32-libdir", 1, 0, 'U' },
3832 { "consumerd64-path", 1, 0, 't' },
3833 { "consumerd64-libdir", 1, 0, 'T' },
3834 { "daemonize", 0, 0, 'd' },
3835 { "sig-parent", 0, 0, 'S' },
3836 { "help", 0, 0, 'h' },
3837 { "group", 1, 0, 'g' },
3838 { "version", 0, 0, 'V' },
3839 { "quiet", 0, 0, 'q' },
3840 { "verbose", 0, 0, 'v' },
3841 { "verbose-consumer", 0, 0, 'Z' },
3842 { "no-kernel", 0, 0, 'N' },
3843 { NULL, 0, 0, 0 }
3844 };
3845
3846 while (1) {
3847 int option_index = 0;
3848 c = getopt_long(argc, argv, "dhqvVSN" "a:c:g:s:C:E:D:F:Z:u:t",
3849 long_options, &option_index);
3850 if (c == -1) {
3851 break;
3852 }
3853
3854 switch (c) {
3855 case 0:
3856 fprintf(stderr, "option %s", long_options[option_index].name);
3857 if (optarg) {
3858 fprintf(stderr, " with arg %s\n", optarg);
3859 }
3860 break;
3861 case 'c':
3862 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3863 break;
3864 case 'a':
3865 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3866 break;
3867 case 'd':
3868 opt_daemon = 1;
3869 break;
3870 case 'g':
3871 opt_tracing_group = optarg;
3872 break;
3873 case 'h':
3874 usage();
3875 exit(EXIT_FAILURE);
3876 case 'V':
3877 fprintf(stdout, "%s\n", VERSION);
3878 exit(EXIT_SUCCESS);
3879 case 'S':
3880 opt_sig_parent = 1;
3881 break;
3882 case 'E':
3883 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3884 break;
3885 case 'C':
3886 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3887 break;
3888 case 'F':
3889 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3890 break;
3891 case 'D':
3892 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3893 break;
3894 case 'H':
3895 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3896 break;
3897 case 'G':
3898 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3899 break;
3900 case 'N':
3901 opt_no_kernel = 1;
3902 break;
3903 case 'q':
3904 opt_quiet = 1;
3905 break;
3906 case 'v':
3907 /* Verbose level can increase using multiple -v */
3908 opt_verbose += 1;
3909 break;
3910 case 'Z':
3911 opt_verbose_consumer += 1;
3912 break;
3913 case 'u':
3914 consumerd32_bin= optarg;
3915 break;
3916 case 'U':
3917 consumerd32_libdir = optarg;
3918 break;
3919 case 't':
3920 consumerd64_bin = optarg;
3921 break;
3922 case 'T':
3923 consumerd64_libdir = optarg;
3924 break;
3925 default:
3926 /* Unknown option or other error.
3927 * Error is printed by getopt, just return */
3928 return -1;
3929 }
3930 }
3931
3932 return 0;
3933 }
3934
3935 /*
3936 * Creates the two needed socket by the daemon.
3937 * apps_sock - The communication socket for all UST apps.
3938 * client_sock - The communication of the cli tool (lttng).
3939 */
3940 static int init_daemon_socket(void)
3941 {
3942 int ret = 0;
3943 mode_t old_umask;
3944
3945 old_umask = umask(0);
3946
3947 /* Create client tool unix socket */
3948 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3949 if (client_sock < 0) {
3950 ERR("Create unix sock failed: %s", client_unix_sock_path);
3951 ret = -1;
3952 goto end;
3953 }
3954
3955 /* File permission MUST be 660 */
3956 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3957 if (ret < 0) {
3958 ERR("Set file permissions failed: %s", client_unix_sock_path);
3959 perror("chmod");
3960 goto end;
3961 }
3962
3963 /* Create the application unix socket */
3964 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3965 if (apps_sock < 0) {
3966 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3967 ret = -1;
3968 goto end;
3969 }
3970
3971 /* File permission MUST be 666 */
3972 ret = chmod(apps_unix_sock_path,
3973 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3974 if (ret < 0) {
3975 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3976 perror("chmod");
3977 goto end;
3978 }
3979
3980 end:
3981 umask(old_umask);
3982 return ret;
3983 }
3984
3985 /*
3986 * Check if the global socket is available, and if a daemon is answering at the
3987 * other side. If yes, error is returned.
3988 */
3989 static int check_existing_daemon(void)
3990 {
3991 if (access(client_unix_sock_path, F_OK) < 0 &&
3992 access(apps_unix_sock_path, F_OK) < 0) {
3993 return 0;
3994 }
3995
3996 /* Is there anybody out there ? */
3997 if (lttng_session_daemon_alive()) {
3998 return -EEXIST;
3999 } else {
4000 return 0;
4001 }
4002 }
4003
4004 /*
4005 * Set the tracing group gid onto the client socket.
4006 *
4007 * Race window between mkdir and chown is OK because we are going from more
4008 * permissive (root.root) to les permissive (root.tracing).
4009 */
4010 static int set_permissions(char *rundir)
4011 {
4012 int ret;
4013 gid_t gid;
4014
4015 gid = allowed_group();
4016 if (gid < 0) {
4017 WARN("No tracing group detected");
4018 ret = 0;
4019 goto end;
4020 }
4021
4022 /* Set lttng run dir */
4023 ret = chown(rundir, 0, gid);
4024 if (ret < 0) {
4025 ERR("Unable to set group on %s", rundir);
4026 perror("chown");
4027 }
4028
4029 /* lttng client socket path */
4030 ret = chown(client_unix_sock_path, 0, gid);
4031 if (ret < 0) {
4032 ERR("Unable to set group on %s", client_unix_sock_path);
4033 perror("chown");
4034 }
4035
4036 /* kconsumer error socket path */
4037 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
4038 if (ret < 0) {
4039 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
4040 perror("chown");
4041 }
4042
4043 /* 64-bit ustconsumer error socket path */
4044 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
4045 if (ret < 0) {
4046 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
4047 perror("chown");
4048 }
4049
4050 /* 32-bit ustconsumer compat32 error socket path */
4051 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
4052 if (ret < 0) {
4053 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
4054 perror("chown");
4055 }
4056
4057 DBG("All permissions are set");
4058
4059 end:
4060 return ret;
4061 }
4062
4063 /*
4064 * Create the pipe used to wake up the kernel thread.
4065 */
4066 static int create_kernel_poll_pipe(void)
4067 {
4068 return pipe2(kernel_poll_pipe, O_CLOEXEC);
4069 }
4070
4071 /*
4072 * Create the application command pipe to wake thread_manage_apps.
4073 */
4074 static int create_apps_cmd_pipe(void)
4075 {
4076 return pipe2(apps_cmd_pipe, O_CLOEXEC);
4077 }
4078
4079 /*
4080 * Create the lttng run directory needed for all global sockets and pipe.
4081 */
4082 static int create_lttng_rundir(const char *rundir)
4083 {
4084 int ret;
4085
4086 DBG3("Creating LTTng run directory: %s", rundir);
4087
4088 ret = mkdir(rundir, S_IRWXU | S_IRWXG );
4089 if (ret < 0) {
4090 if (errno != EEXIST) {
4091 ERR("Unable to create %s", rundir);
4092 goto error;
4093 } else {
4094 ret = 0;
4095 }
4096 }
4097
4098 error:
4099 return ret;
4100 }
4101
4102 /*
4103 * Setup sockets and directory needed by the kconsumerd communication with the
4104 * session daemon.
4105 */
4106 static int set_consumer_sockets(struct consumer_data *consumer_data,
4107 const char *rundir)
4108 {
4109 int ret;
4110 char path[PATH_MAX];
4111
4112 switch (consumer_data->type) {
4113 case LTTNG_CONSUMER_KERNEL:
4114 snprintf(path, PATH_MAX, DEFAULT_KCONSUMERD_PATH, rundir);
4115 break;
4116 case LTTNG_CONSUMER64_UST:
4117 snprintf(path, PATH_MAX, DEFAULT_USTCONSUMERD64_PATH, rundir);
4118 break;
4119 case LTTNG_CONSUMER32_UST:
4120 snprintf(path, PATH_MAX, DEFAULT_USTCONSUMERD32_PATH, rundir);
4121 break;
4122 default:
4123 ERR("Consumer type unknown");
4124 ret = -EINVAL;
4125 goto error;
4126 }
4127
4128 DBG2("Creating consumer directory: %s", path);
4129
4130 ret = mkdir(path, S_IRWXU | S_IRWXG);
4131 if (ret < 0) {
4132 if (errno != EEXIST) {
4133 ERR("Failed to create %s", path);
4134 goto error;
4135 }
4136 ret = 0;
4137 }
4138
4139 /* Create the kconsumerd error unix socket */
4140 consumer_data->err_sock =
4141 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
4142 if (consumer_data->err_sock < 0) {
4143 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
4144 ret = -1;
4145 goto error;
4146 }
4147
4148 /* File permission MUST be 660 */
4149 ret = chmod(consumer_data->err_unix_sock_path,
4150 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
4151 if (ret < 0) {
4152 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
4153 PERROR("chmod");
4154 goto error;
4155 }
4156
4157 error:
4158 return ret;
4159 }
4160
4161 /*
4162 * Signal handler for the daemon
4163 *
4164 * Simply stop all worker threads, leaving main() return gracefully after
4165 * joining all threads and calling cleanup().
4166 */
4167 static void sighandler(int sig)
4168 {
4169 switch (sig) {
4170 case SIGPIPE:
4171 DBG("SIGPIPE caugth");
4172 return;
4173 case SIGINT:
4174 DBG("SIGINT caugth");
4175 stop_threads();
4176 break;
4177 case SIGTERM:
4178 DBG("SIGTERM caugth");
4179 stop_threads();
4180 break;
4181 default:
4182 break;
4183 }
4184 }
4185
4186 /*
4187 * Setup signal handler for :
4188 * SIGINT, SIGTERM, SIGPIPE
4189 */
4190 static int set_signal_handler(void)
4191 {
4192 int ret = 0;
4193 struct sigaction sa;
4194 sigset_t sigset;
4195
4196 if ((ret = sigemptyset(&sigset)) < 0) {
4197 perror("sigemptyset");
4198 return ret;
4199 }
4200
4201 sa.sa_handler = sighandler;
4202 sa.sa_mask = sigset;
4203 sa.sa_flags = 0;
4204 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
4205 perror("sigaction");
4206 return ret;
4207 }
4208
4209 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
4210 perror("sigaction");
4211 return ret;
4212 }
4213
4214 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
4215 perror("sigaction");
4216 return ret;
4217 }
4218
4219 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
4220
4221 return ret;
4222 }
4223
4224 /*
4225 * Set open files limit to unlimited. This daemon can open a large number of
4226 * file descriptors in order to consumer multiple kernel traces.
4227 */
4228 static void set_ulimit(void)
4229 {
4230 int ret;
4231 struct rlimit lim;
4232
4233 /* The kernel does not allowed an infinite limit for open files */
4234 lim.rlim_cur = 65535;
4235 lim.rlim_max = 65535;
4236
4237 ret = setrlimit(RLIMIT_NOFILE, &lim);
4238 if (ret < 0) {
4239 perror("failed to set open files limit");
4240 }
4241 }
4242
4243 /*
4244 * main
4245 */
4246 int main(int argc, char **argv)
4247 {
4248 int ret = 0;
4249 void *status;
4250 const char *home_path;
4251
4252 rcu_register_thread();
4253
4254 /* Create thread quit pipe */
4255 if ((ret = init_thread_quit_pipe()) < 0) {
4256 goto error;
4257 }
4258
4259 setup_consumerd_path();
4260
4261 /* Parse arguments */
4262 progname = argv[0];
4263 if ((ret = parse_args(argc, argv) < 0)) {
4264 goto error;
4265 }
4266
4267 /* Daemonize */
4268 if (opt_daemon) {
4269 ret = daemon(0, 0);
4270 if (ret < 0) {
4271 perror("daemon");
4272 goto error;
4273 }
4274 }
4275
4276 /* Check if daemon is UID = 0 */
4277 is_root = !getuid();
4278
4279 if (is_root) {
4280 rundir = strdup(DEFAULT_LTTNG_RUNDIR);
4281
4282 /* Create global run dir with root access */
4283 ret = create_lttng_rundir(rundir);
4284 if (ret < 0) {
4285 goto error;
4286 }
4287
4288 if (strlen(apps_unix_sock_path) == 0) {
4289 snprintf(apps_unix_sock_path, PATH_MAX,
4290 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
4291 }
4292
4293 if (strlen(client_unix_sock_path) == 0) {
4294 snprintf(client_unix_sock_path, PATH_MAX,
4295 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
4296 }
4297
4298 /* Set global SHM for ust */
4299 if (strlen(wait_shm_path) == 0) {
4300 snprintf(wait_shm_path, PATH_MAX,
4301 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
4302 }
4303
4304 /* Setup kernel consumerd path */
4305 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX,
4306 DEFAULT_KCONSUMERD_ERR_SOCK_PATH, rundir);
4307 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX,
4308 DEFAULT_KCONSUMERD_CMD_SOCK_PATH, rundir);
4309
4310 DBG2("Kernel consumer err path: %s",
4311 kconsumer_data.err_unix_sock_path);
4312 DBG2("Kernel consumer cmd path: %s",
4313 kconsumer_data.cmd_unix_sock_path);
4314 } else {
4315 home_path = get_home_dir();
4316 if (home_path == NULL) {
4317 /* TODO: Add --socket PATH option */
4318 ERR("Can't get HOME directory for sockets creation.");
4319 ret = -EPERM;
4320 goto error;
4321 }
4322
4323 /*
4324 * Create rundir from home path. This will create something like
4325 * $HOME/.lttng
4326 */
4327 ret = asprintf(&rundir, DEFAULT_LTTNG_HOME_RUNDIR, home_path);
4328 if (ret < 0) {
4329 ret = -ENOMEM;
4330 goto error;
4331 }
4332
4333 ret = create_lttng_rundir(rundir);
4334 if (ret < 0) {
4335 goto error;
4336 }
4337
4338 if (strlen(apps_unix_sock_path) == 0) {
4339 snprintf(apps_unix_sock_path, PATH_MAX,
4340 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
4341 }
4342
4343 /* Set the cli tool unix socket path */
4344 if (strlen(client_unix_sock_path) == 0) {
4345 snprintf(client_unix_sock_path, PATH_MAX,
4346 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
4347 }
4348
4349 /* Set global SHM for ust */
4350 if (strlen(wait_shm_path) == 0) {
4351 snprintf(wait_shm_path, PATH_MAX,
4352 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
4353 }
4354 }
4355
4356 DBG("Client socket path %s", client_unix_sock_path);
4357 DBG("Application socket path %s", apps_unix_sock_path);
4358 DBG("LTTng run directory path: %s", rundir);
4359
4360 /* 32 bits consumerd path setup */
4361 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX,
4362 DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH, rundir);
4363 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX,
4364 DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH, rundir);
4365
4366 DBG2("UST consumer 32 bits err path: %s",
4367 ustconsumer32_data.err_unix_sock_path);
4368 DBG2("UST consumer 32 bits cmd path: %s",
4369 ustconsumer32_data.cmd_unix_sock_path);
4370
4371 /* 64 bits consumerd path setup */
4372 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX,
4373 DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH, rundir);
4374 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX,
4375 DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH, rundir);
4376
4377 DBG2("UST consumer 64 bits err path: %s",
4378 ustconsumer64_data.err_unix_sock_path);
4379 DBG2("UST consumer 64 bits cmd path: %s",
4380 ustconsumer64_data.cmd_unix_sock_path);
4381
4382 /*
4383 * See if daemon already exist.
4384 */
4385 if ((ret = check_existing_daemon()) < 0) {
4386 ERR("Already running daemon.\n");
4387 /*
4388 * We do not goto exit because we must not cleanup()
4389 * because a daemon is already running.
4390 */
4391 goto error;
4392 }
4393
4394 /* After this point, we can safely call cleanup() with "goto exit" */
4395
4396 /*
4397 * These actions must be executed as root. We do that *after* setting up
4398 * the sockets path because we MUST make the check for another daemon using
4399 * those paths *before* trying to set the kernel consumer sockets and init
4400 * kernel tracer.
4401 */
4402 if (is_root) {
4403 ret = set_consumer_sockets(&kconsumer_data, rundir);
4404 if (ret < 0) {
4405 goto exit;
4406 }
4407
4408 /* Setup kernel tracer */
4409 if (!opt_no_kernel) {
4410 init_kernel_tracer();
4411 }
4412
4413 /* Set ulimit for open files */
4414 set_ulimit();
4415 }
4416
4417 ret = set_consumer_sockets(&ustconsumer64_data, rundir);
4418 if (ret < 0) {
4419 goto exit;
4420 }
4421
4422 ret = set_consumer_sockets(&ustconsumer32_data, rundir);
4423 if (ret < 0) {
4424 goto exit;
4425 }
4426
4427 if ((ret = set_signal_handler()) < 0) {
4428 goto exit;
4429 }
4430
4431 /* Setup the needed unix socket */
4432 if ((ret = init_daemon_socket()) < 0) {
4433 goto exit;
4434 }
4435
4436 /* Set credentials to socket */
4437 if (is_root && ((ret = set_permissions(rundir)) < 0)) {
4438 goto exit;
4439 }
4440
4441 /* Get parent pid if -S, --sig-parent is specified. */
4442 if (opt_sig_parent) {
4443 ppid = getppid();
4444 }
4445
4446 /* Setup the kernel pipe for waking up the kernel thread */
4447 if ((ret = create_kernel_poll_pipe()) < 0) {
4448 goto exit;
4449 }
4450
4451 /* Setup the thread apps communication pipe. */
4452 if ((ret = create_apps_cmd_pipe()) < 0) {
4453 goto exit;
4454 }
4455
4456 /* Init UST command queue. */
4457 cds_wfq_init(&ust_cmd_queue.queue);
4458
4459 /* Init UST app hash table */
4460 ust_app_ht_alloc();
4461
4462 /*
4463 * Get session list pointer. This pointer MUST NOT be free(). This list is
4464 * statically declared in session.c
4465 */
4466 session_list_ptr = session_get_list();
4467
4468 /* Set up max poll set size */
4469 lttng_poll_set_max_size();
4470
4471 /* Create thread to manage the client socket */
4472 ret = pthread_create(&client_thread, NULL,
4473 thread_manage_clients, (void *) NULL);
4474 if (ret != 0) {
4475 perror("pthread_create clients");
4476 goto exit_client;
4477 }
4478
4479 /* Create thread to dispatch registration */
4480 ret = pthread_create(&dispatch_thread, NULL,
4481 thread_dispatch_ust_registration, (void *) NULL);
4482 if (ret != 0) {
4483 perror("pthread_create dispatch");
4484 goto exit_dispatch;
4485 }
4486
4487 /* Create thread to manage application registration. */
4488 ret = pthread_create(&reg_apps_thread, NULL,
4489 thread_registration_apps, (void *) NULL);
4490 if (ret != 0) {
4491 perror("pthread_create registration");
4492 goto exit_reg_apps;
4493 }
4494
4495 /* Create thread to manage application socket */
4496 ret = pthread_create(&apps_thread, NULL,
4497 thread_manage_apps, (void *) NULL);
4498 if (ret != 0) {
4499 perror("pthread_create apps");
4500 goto exit_apps;
4501 }
4502
4503 /* Create kernel thread to manage kernel event */
4504 ret = pthread_create(&kernel_thread, NULL,
4505 thread_manage_kernel, (void *) NULL);
4506 if (ret != 0) {
4507 perror("pthread_create kernel");
4508 goto exit_kernel;
4509 }
4510
4511 ret = pthread_join(kernel_thread, &status);
4512 if (ret != 0) {
4513 perror("pthread_join");
4514 goto error; /* join error, exit without cleanup */
4515 }
4516
4517 exit_kernel:
4518 ret = pthread_join(apps_thread, &status);
4519 if (ret != 0) {
4520 perror("pthread_join");
4521 goto error; /* join error, exit without cleanup */
4522 }
4523
4524 exit_apps:
4525 ret = pthread_join(reg_apps_thread, &status);
4526 if (ret != 0) {
4527 perror("pthread_join");
4528 goto error; /* join error, exit without cleanup */
4529 }
4530
4531 exit_reg_apps:
4532 ret = pthread_join(dispatch_thread, &status);
4533 if (ret != 0) {
4534 perror("pthread_join");
4535 goto error; /* join error, exit without cleanup */
4536 }
4537
4538 exit_dispatch:
4539 ret = pthread_join(client_thread, &status);
4540 if (ret != 0) {
4541 perror("pthread_join");
4542 goto error; /* join error, exit without cleanup */
4543 }
4544
4545 ret = join_consumer_thread(&kconsumer_data);
4546 if (ret != 0) {
4547 perror("join_consumer");
4548 goto error; /* join error, exit without cleanup */
4549 }
4550
4551 exit_client:
4552 exit:
4553 /*
4554 * cleanup() is called when no other thread is running.
4555 */
4556 rcu_thread_online();
4557 cleanup();
4558 rcu_thread_offline();
4559 rcu_unregister_thread();
4560 if (!ret) {
4561 exit(EXIT_SUCCESS);
4562 }
4563 error:
4564 exit(EXIT_FAILURE);
4565 }
LTTng 2.0 tools and control repository
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