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Fix DBG message grammatical error
[lttng-tools.git] / src / bin / lttng-sessiond / main.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the Free
7 * Software Foundation; only version 2 of the License.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
16 * Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18
19 #define _GNU_SOURCE
20 #include <fcntl.h>
21 #include <getopt.h>
22 #include <grp.h>
23 #include <limits.h>
24 #include <pthread.h>
25 #include <semaphore.h>
26 #include <signal.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <sys/mman.h>
31 #include <sys/mount.h>
32 #include <sys/resource.h>
33 #include <sys/socket.h>
34 #include <sys/stat.h>
35 #include <sys/types.h>
36 #include <sys/wait.h>
37 #include <urcu/futex.h>
38 #include <unistd.h>
39 #include <config.h>
40
41 #include <bin/lttng-consumerd/lttng-consumerd.h>
42 #include <common/lttngerr.h>
43 #include <common/kernel-consumer/kernel-consumer.h>
44 #include <common/ust-consumer/ust-consumer.h>
45 #include <common/runas.h>
46 #include <common/compat/poll.h>
47
48 #include "lttng-sessiond.h"
49 #include "channel.h"
50 #include "context.h"
51 #include "event.h"
52 #include "futex.h"
53 #include "kernel.h"
54 #include "shm.h"
55 #include "ust-ctl.h"
56 #include "utils.h"
57
58 #define CONSUMERD_FILE "lttng-consumerd"
59
60 struct consumer_data {
61 enum lttng_consumer_type type;
62
63 pthread_t thread; /* Worker thread interacting with the consumer */
64 sem_t sem;
65
66 /* Mutex to control consumerd pid assignation */
67 pthread_mutex_t pid_mutex;
68 pid_t pid;
69
70 int err_sock;
71 int cmd_sock;
72
73 /* consumer error and command Unix socket path */
74 char err_unix_sock_path[PATH_MAX];
75 char cmd_unix_sock_path[PATH_MAX];
76 };
77
78 /* Const values */
79 const char default_home_dir[] = DEFAULT_HOME_DIR;
80 const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
81 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
82 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
83
84 /* Variables */
85 int opt_verbose; /* Not static for lttngerr.h */
86 int opt_verbose_consumer; /* Not static for lttngerr.h */
87 int opt_quiet; /* Not static for lttngerr.h */
88
89 const char *progname;
90 const char *opt_tracing_group;
91 static int opt_sig_parent;
92 static int opt_daemon;
93 static int opt_no_kernel;
94 static int is_root; /* Set to 1 if the daemon is running as root */
95 static pid_t ppid; /* Parent PID for --sig-parent option */
96 static char *rundir;
97
98 /* Consumer daemon specific control data */
99 static struct consumer_data kconsumer_data = {
100 .type = LTTNG_CONSUMER_KERNEL,
101 .err_unix_sock_path = KCONSUMERD_ERR_SOCK_PATH,
102 .cmd_unix_sock_path = KCONSUMERD_CMD_SOCK_PATH,
103 };
104 static struct consumer_data ustconsumer64_data = {
105 .type = LTTNG_CONSUMER64_UST,
106 .err_unix_sock_path = USTCONSUMERD64_ERR_SOCK_PATH,
107 .cmd_unix_sock_path = USTCONSUMERD64_CMD_SOCK_PATH,
108 };
109 static struct consumer_data ustconsumer32_data = {
110 .type = LTTNG_CONSUMER32_UST,
111 .err_unix_sock_path = USTCONSUMERD32_ERR_SOCK_PATH,
112 .cmd_unix_sock_path = USTCONSUMERD32_CMD_SOCK_PATH,
113 };
114
115 static int dispatch_thread_exit;
116
117 /* Global application Unix socket path */
118 static char apps_unix_sock_path[PATH_MAX];
119 /* Global client Unix socket path */
120 static char client_unix_sock_path[PATH_MAX];
121 /* global wait shm path for UST */
122 static char wait_shm_path[PATH_MAX];
123
124 /* Sockets and FDs */
125 static int client_sock;
126 static int apps_sock;
127 static int kernel_tracer_fd;
128 static int kernel_poll_pipe[2];
129
130 /*
131 * Quit pipe for all threads. This permits a single cancellation point
132 * for all threads when receiving an event on the pipe.
133 */
134 static int thread_quit_pipe[2];
135
136 /*
137 * This pipe is used to inform the thread managing application communication
138 * that a command is queued and ready to be processed.
139 */
140 static int apps_cmd_pipe[2];
141
142 /* Pthread, Mutexes and Semaphores */
143 static pthread_t apps_thread;
144 static pthread_t reg_apps_thread;
145 static pthread_t client_thread;
146 static pthread_t kernel_thread;
147 static pthread_t dispatch_thread;
148
149
150 /*
151 * UST registration command queue. This queue is tied with a futex and uses a N
152 * wakers / 1 waiter implemented and detailed in futex.c/.h
153 *
154 * The thread_manage_apps and thread_dispatch_ust_registration interact with
155 * this queue and the wait/wake scheme.
156 */
157 static struct ust_cmd_queue ust_cmd_queue;
158
159 /*
160 * Pointer initialized before thread creation.
161 *
162 * This points to the tracing session list containing the session count and a
163 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
164 * MUST NOT be taken if you call a public function in session.c.
165 *
166 * The lock is nested inside the structure: session_list_ptr->lock. Please use
167 * session_lock_list and session_unlock_list for lock acquisition.
168 */
169 static struct ltt_session_list *session_list_ptr;
170
171 int ust_consumerd64_fd = -1;
172 int ust_consumerd32_fd = -1;
173
174 static const char *consumerd32_bin = CONFIG_CONSUMERD32_BIN;
175 static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
176 static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
177 static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
178
179 static
180 void setup_consumerd_path(void)
181 {
182 const char *bin, *libdir;
183
184 /*
185 * Allow INSTALL_BIN_PATH to be used as a target path for the
186 * native architecture size consumer if CONFIG_CONSUMER*_PATH
187 * has not been defined.
188 */
189 #if (CAA_BITS_PER_LONG == 32)
190 if (!consumerd32_bin[0]) {
191 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
192 }
193 if (!consumerd32_libdir[0]) {
194 consumerd32_libdir = INSTALL_LIB_PATH;
195 }
196 #elif (CAA_BITS_PER_LONG == 64)
197 if (!consumerd64_bin[0]) {
198 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
199 }
200 if (!consumerd64_libdir[0]) {
201 consumerd64_libdir = INSTALL_LIB_PATH;
202 }
203 #else
204 #error "Unknown bitness"
205 #endif
206
207 /*
208 * runtime env. var. overrides the build default.
209 */
210 bin = getenv("LTTNG_CONSUMERD32_BIN");
211 if (bin) {
212 consumerd32_bin = bin;
213 }
214 bin = getenv("LTTNG_CONSUMERD64_BIN");
215 if (bin) {
216 consumerd64_bin = bin;
217 }
218 libdir = getenv("LTTNG_TOOLS_CONSUMERD32_LIBDIR");
219 if (libdir) {
220 consumerd32_libdir = libdir;
221 }
222 libdir = getenv("LTTNG_TOOLS_CONSUMERD64_LIBDIR");
223 if (libdir) {
224 consumerd64_libdir = libdir;
225 }
226 }
227
228 /*
229 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
230 */
231 static int create_thread_poll_set(struct lttng_poll_event *events,
232 unsigned int size)
233 {
234 int ret;
235
236 if (events == NULL || size == 0) {
237 ret = -1;
238 goto error;
239 }
240
241 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
242 if (ret < 0) {
243 goto error;
244 }
245
246 /* Add quit pipe */
247 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
248 if (ret < 0) {
249 goto error;
250 }
251
252 return 0;
253
254 error:
255 return ret;
256 }
257
258 /*
259 * Check if the thread quit pipe was triggered.
260 *
261 * Return 1 if it was triggered else 0;
262 */
263 static int check_thread_quit_pipe(int fd, uint32_t events)
264 {
265 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
266 return 1;
267 }
268
269 return 0;
270 }
271
272 /*
273 * Remove modules in reverse load order.
274 */
275 static int modprobe_remove_kernel_modules(void)
276 {
277 int ret = 0, i;
278 char modprobe[256];
279
280 for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
281 ret = snprintf(modprobe, sizeof(modprobe),
282 "/sbin/modprobe -r -q %s",
283 kernel_modules_list[i].name);
284 if (ret < 0) {
285 perror("snprintf modprobe -r");
286 goto error;
287 }
288 modprobe[sizeof(modprobe) - 1] = '\0';
289 ret = system(modprobe);
290 if (ret == -1) {
291 ERR("Unable to launch modprobe -r for module %s",
292 kernel_modules_list[i].name);
293 } else if (kernel_modules_list[i].required
294 && WEXITSTATUS(ret) != 0) {
295 ERR("Unable to remove module %s",
296 kernel_modules_list[i].name);
297 } else {
298 DBG("Modprobe removal successful %s",
299 kernel_modules_list[i].name);
300 }
301 }
302
303 error:
304 return ret;
305 }
306
307 /*
308 * Return group ID of the tracing group or -1 if not found.
309 */
310 static gid_t allowed_group(void)
311 {
312 struct group *grp;
313
314 if (opt_tracing_group) {
315 grp = getgrnam(opt_tracing_group);
316 } else {
317 grp = getgrnam(default_tracing_group);
318 }
319 if (!grp) {
320 return -1;
321 } else {
322 return grp->gr_gid;
323 }
324 }
325
326 /*
327 * Init thread quit pipe.
328 *
329 * Return -1 on error or 0 if all pipes are created.
330 */
331 static int init_thread_quit_pipe(void)
332 {
333 int ret;
334
335 ret = pipe2(thread_quit_pipe, O_CLOEXEC);
336 if (ret < 0) {
337 perror("thread quit pipe");
338 goto error;
339 }
340
341 error:
342 return ret;
343 }
344
345 /*
346 * Complete teardown of a kernel session. This free all data structure related
347 * to a kernel session and update counter.
348 */
349 static void teardown_kernel_session(struct ltt_session *session)
350 {
351 if (!session->kernel_session) {
352 DBG3("No kernel session when tearingdown session");
353 return;
354 }
355
356 DBG("Tearing down kernel session");
357
358 /*
359 * If a custom kernel consumer was registered, close the socket before
360 * tearing down the complete kernel session structure
361 */
362 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
363 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
364 }
365
366 trace_kernel_destroy_session(session->kernel_session);
367 }
368
369 /*
370 * Complete teardown of all UST sessions. This will free everything on his path
371 * and destroy the core essence of all ust sessions :)
372 */
373 static void teardown_ust_session(struct ltt_session *session)
374 {
375 int ret;
376
377 if (!session->ust_session) {
378 DBG3("No UST session when tearingdown session");
379 return;
380 }
381
382 DBG("Tearing down UST session(s)");
383
384 ret = ust_app_destroy_trace_all(session->ust_session);
385 if (ret) {
386 ERR("Error in ust_app_destroy_trace_all");
387 }
388
389 trace_ust_destroy_session(session->ust_session);
390 }
391
392 /*
393 * Stop all threads by closing the thread quit pipe.
394 */
395 static void stop_threads(void)
396 {
397 int ret;
398
399 /* Stopping all threads */
400 DBG("Terminating all threads");
401 ret = notify_thread_pipe(thread_quit_pipe[1]);
402 if (ret < 0) {
403 ERR("write error on thread quit pipe");
404 }
405
406 /* Dispatch thread */
407 dispatch_thread_exit = 1;
408 futex_nto1_wake(&ust_cmd_queue.futex);
409 }
410
411 /*
412 * Cleanup the daemon
413 */
414 static void cleanup(void)
415 {
416 int ret;
417 char *cmd;
418 struct ltt_session *sess, *stmp;
419
420 DBG("Cleaning up");
421
422 DBG("Removing %s directory", rundir);
423 ret = asprintf(&cmd, "rm -rf %s", rundir);
424 if (ret < 0) {
425 ERR("asprintf failed. Something is really wrong!");
426 }
427
428 /* Remove lttng run directory */
429 ret = system(cmd);
430 if (ret < 0) {
431 ERR("Unable to clean %s", rundir);
432 }
433 free(cmd);
434
435 DBG("Cleaning up all session");
436
437 /* Destroy session list mutex */
438 if (session_list_ptr != NULL) {
439 pthread_mutex_destroy(&session_list_ptr->lock);
440
441 /* Cleanup ALL session */
442 cds_list_for_each_entry_safe(sess, stmp,
443 &session_list_ptr->head, list) {
444 teardown_kernel_session(sess);
445 teardown_ust_session(sess);
446 free(sess);
447 }
448 }
449
450 DBG("Closing all UST sockets");
451 ust_app_clean_list();
452
453 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
454
455 if (is_root && !opt_no_kernel) {
456 DBG2("Closing kernel fd");
457 close(kernel_tracer_fd);
458 DBG("Unloading kernel modules");
459 modprobe_remove_kernel_modules();
460 }
461
462 close(thread_quit_pipe[0]);
463 close(thread_quit_pipe[1]);
464
465 /* <fun> */
466 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
467 "Matthew, BEET driven development works!%c[%dm",
468 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
469 /* </fun> */
470 }
471
472 /*
473 * Send data on a unix socket using the liblttsessiondcomm API.
474 *
475 * Return lttcomm error code.
476 */
477 static int send_unix_sock(int sock, void *buf, size_t len)
478 {
479 /* Check valid length */
480 if (len <= 0) {
481 return -1;
482 }
483
484 return lttcomm_send_unix_sock(sock, buf, len);
485 }
486
487 /*
488 * Free memory of a command context structure.
489 */
490 static void clean_command_ctx(struct command_ctx **cmd_ctx)
491 {
492 DBG("Clean command context structure");
493 if (*cmd_ctx) {
494 if ((*cmd_ctx)->llm) {
495 free((*cmd_ctx)->llm);
496 }
497 if ((*cmd_ctx)->lsm) {
498 free((*cmd_ctx)->lsm);
499 }
500 free(*cmd_ctx);
501 *cmd_ctx = NULL;
502 }
503 }
504
505 /*
506 * Send all stream fds of kernel channel to the consumer.
507 */
508 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
509 int sock, struct ltt_kernel_channel *channel,
510 uid_t uid, gid_t gid)
511 {
512 int ret;
513 struct ltt_kernel_stream *stream;
514 struct lttcomm_consumer_msg lkm;
515
516 DBG("Sending streams of channel %s to kernel consumer",
517 channel->channel->name);
518
519 /* Send channel */
520 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
521 lkm.u.channel.channel_key = channel->fd;
522 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
523 lkm.u.channel.mmap_len = 0; /* for kernel */
524 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
525 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
526 if (ret < 0) {
527 perror("send consumer channel");
528 goto error;
529 }
530
531 /* Send streams */
532 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
533 if (!stream->fd) {
534 continue;
535 }
536 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
537 lkm.u.stream.channel_key = channel->fd;
538 lkm.u.stream.stream_key = stream->fd;
539 lkm.u.stream.state = stream->state;
540 lkm.u.stream.output = channel->channel->attr.output;
541 lkm.u.stream.mmap_len = 0; /* for kernel */
542 lkm.u.stream.uid = uid;
543 lkm.u.stream.gid = gid;
544 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
545 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
546 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
547 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
548 if (ret < 0) {
549 perror("send consumer stream");
550 goto error;
551 }
552 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
553 if (ret < 0) {
554 perror("send consumer stream ancillary data");
555 goto error;
556 }
557 }
558
559 DBG("consumer channel streams sent");
560
561 return 0;
562
563 error:
564 return ret;
565 }
566
567 /*
568 * Send all stream fds of the kernel session to the consumer.
569 */
570 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
571 struct ltt_kernel_session *session)
572 {
573 int ret;
574 struct ltt_kernel_channel *chan;
575 struct lttcomm_consumer_msg lkm;
576 int sock = session->consumer_fd;
577
578 DBG("Sending metadata stream fd");
579
580 /* Extra protection. It's NOT supposed to be set to 0 at this point */
581 if (session->consumer_fd == 0) {
582 session->consumer_fd = consumer_data->cmd_sock;
583 }
584
585 if (session->metadata_stream_fd != 0) {
586 /* Send metadata channel fd */
587 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
588 lkm.u.channel.channel_key = session->metadata->fd;
589 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
590 lkm.u.channel.mmap_len = 0; /* for kernel */
591 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
592 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
593 if (ret < 0) {
594 perror("send consumer channel");
595 goto error;
596 }
597
598 /* Send metadata stream fd */
599 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
600 lkm.u.stream.channel_key = session->metadata->fd;
601 lkm.u.stream.stream_key = session->metadata_stream_fd;
602 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
603 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
604 lkm.u.stream.mmap_len = 0; /* for kernel */
605 lkm.u.stream.uid = session->uid;
606 lkm.u.stream.gid = session->gid;
607 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
608 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
609 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
610 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
611 if (ret < 0) {
612 perror("send consumer stream");
613 goto error;
614 }
615 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
616 if (ret < 0) {
617 perror("send consumer stream");
618 goto error;
619 }
620 }
621
622 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
623 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
624 session->uid, session->gid);
625 if (ret < 0) {
626 goto error;
627 }
628 }
629
630 DBG("consumer fds (metadata and channel streams) sent");
631
632 return 0;
633
634 error:
635 return ret;
636 }
637
638 /*
639 * Notify UST applications using the shm mmap futex.
640 */
641 static int notify_ust_apps(int active)
642 {
643 char *wait_shm_mmap;
644
645 DBG("Notifying applications of session daemon state: %d", active);
646
647 /* See shm.c for this call implying mmap, shm and futex calls */
648 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
649 if (wait_shm_mmap == NULL) {
650 goto error;
651 }
652
653 /* Wake waiting process */
654 futex_wait_update((int32_t *) wait_shm_mmap, active);
655
656 /* Apps notified successfully */
657 return 0;
658
659 error:
660 return -1;
661 }
662
663 /*
664 * Setup the outgoing data buffer for the response (llm) by allocating the
665 * right amount of memory and copying the original information from the lsm
666 * structure.
667 *
668 * Return total size of the buffer pointed by buf.
669 */
670 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
671 {
672 int ret, buf_size;
673
674 buf_size = size;
675
676 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
677 if (cmd_ctx->llm == NULL) {
678 perror("zmalloc");
679 ret = -ENOMEM;
680 goto error;
681 }
682
683 /* Copy common data */
684 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
685 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
686
687 cmd_ctx->llm->data_size = size;
688 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
689
690 return buf_size;
691
692 error:
693 return ret;
694 }
695
696 /*
697 * Update the kernel poll set of all channel fd available over all tracing
698 * session. Add the wakeup pipe at the end of the set.
699 */
700 static int update_kernel_poll(struct lttng_poll_event *events)
701 {
702 int ret;
703 struct ltt_session *session;
704 struct ltt_kernel_channel *channel;
705
706 DBG("Updating kernel poll set");
707
708 session_lock_list();
709 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
710 session_lock(session);
711 if (session->kernel_session == NULL) {
712 session_unlock(session);
713 continue;
714 }
715
716 cds_list_for_each_entry(channel,
717 &session->kernel_session->channel_list.head, list) {
718 /* Add channel fd to the kernel poll set */
719 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
720 if (ret < 0) {
721 session_unlock(session);
722 goto error;
723 }
724 DBG("Channel fd %d added to kernel set", channel->fd);
725 }
726 session_unlock(session);
727 }
728 session_unlock_list();
729
730 return 0;
731
732 error:
733 session_unlock_list();
734 return -1;
735 }
736
737 /*
738 * Find the channel fd from 'fd' over all tracing session. When found, check
739 * for new channel stream and send those stream fds to the kernel consumer.
740 *
741 * Useful for CPU hotplug feature.
742 */
743 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
744 {
745 int ret = 0;
746 struct ltt_session *session;
747 struct ltt_kernel_channel *channel;
748
749 DBG("Updating kernel streams for channel fd %d", fd);
750
751 session_lock_list();
752 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
753 session_lock(session);
754 if (session->kernel_session == NULL) {
755 session_unlock(session);
756 continue;
757 }
758
759 /* This is not suppose to be 0 but this is an extra security check */
760 if (session->kernel_session->consumer_fd == 0) {
761 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
762 }
763
764 cds_list_for_each_entry(channel,
765 &session->kernel_session->channel_list.head, list) {
766 if (channel->fd == fd) {
767 DBG("Channel found, updating kernel streams");
768 ret = kernel_open_channel_stream(channel);
769 if (ret < 0) {
770 goto error;
771 }
772
773 /*
774 * Have we already sent fds to the consumer? If yes, it means
775 * that tracing is started so it is safe to send our updated
776 * stream fds.
777 */
778 if (session->kernel_session->consumer_fds_sent == 1) {
779 ret = send_kconsumer_channel_streams(consumer_data,
780 session->kernel_session->consumer_fd, channel,
781 session->uid, session->gid);
782 if (ret < 0) {
783 goto error;
784 }
785 }
786 goto error;
787 }
788 }
789 session_unlock(session);
790 }
791 session_unlock_list();
792 return ret;
793
794 error:
795 session_unlock(session);
796 session_unlock_list();
797 return ret;
798 }
799
800 /*
801 * For each tracing session, update newly registered apps.
802 */
803 static void update_ust_app(int app_sock)
804 {
805 struct ltt_session *sess, *stmp;
806
807 /* For all tracing session(s) */
808 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
809 if (sess->ust_session) {
810 ust_app_global_update(sess->ust_session, app_sock);
811 }
812 }
813 }
814
815 /*
816 * This thread manage event coming from the kernel.
817 *
818 * Features supported in this thread:
819 * -) CPU Hotplug
820 */
821 static void *thread_manage_kernel(void *data)
822 {
823 int ret, i, pollfd, update_poll_flag = 1;
824 uint32_t revents, nb_fd;
825 char tmp;
826 struct lttng_poll_event events;
827
828 DBG("Thread manage kernel started");
829
830 ret = create_thread_poll_set(&events, 2);
831 if (ret < 0) {
832 goto error;
833 }
834
835 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
836 if (ret < 0) {
837 goto error;
838 }
839
840 while (1) {
841 if (update_poll_flag == 1) {
842 /*
843 * Reset number of fd in the poll set. Always 2 since there is the thread
844 * quit pipe and the kernel pipe.
845 */
846 events.nb_fd = 2;
847
848 ret = update_kernel_poll(&events);
849 if (ret < 0) {
850 goto error;
851 }
852 update_poll_flag = 0;
853 }
854
855 nb_fd = LTTNG_POLL_GETNB(&events);
856
857 DBG("Thread kernel polling on %d fds", nb_fd);
858
859 /* Zeroed the poll events */
860 lttng_poll_reset(&events);
861
862 /* Poll infinite value of time */
863 ret = lttng_poll_wait(&events, -1);
864 if (ret < 0) {
865 goto error;
866 } else if (ret == 0) {
867 /* Should not happen since timeout is infinite */
868 ERR("Return value of poll is 0 with an infinite timeout.\n"
869 "This should not have happened! Continuing...");
870 continue;
871 }
872
873 for (i = 0; i < nb_fd; i++) {
874 /* Fetch once the poll data */
875 revents = LTTNG_POLL_GETEV(&events, i);
876 pollfd = LTTNG_POLL_GETFD(&events, i);
877
878 /* Thread quit pipe has been closed. Killing thread. */
879 ret = check_thread_quit_pipe(pollfd, revents);
880 if (ret) {
881 goto error;
882 }
883
884 /* Check for data on kernel pipe */
885 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
886 ret = read(kernel_poll_pipe[0], &tmp, 1);
887 update_poll_flag = 1;
888 continue;
889 } else {
890 /*
891 * New CPU detected by the kernel. Adding kernel stream to
892 * kernel session and updating the kernel consumer
893 */
894 if (revents & LPOLLIN) {
895 ret = update_kernel_stream(&kconsumer_data, pollfd);
896 if (ret < 0) {
897 continue;
898 }
899 break;
900 /*
901 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
902 * and unregister kernel stream at this point.
903 */
904 }
905 }
906 }
907 }
908
909 error:
910 DBG("Kernel thread dying");
911 close(kernel_poll_pipe[0]);
912 close(kernel_poll_pipe[1]);
913
914 lttng_poll_clean(&events);
915
916 return NULL;
917 }
918
919 /*
920 * This thread manage the consumer error sent back to the session daemon.
921 */
922 static void *thread_manage_consumer(void *data)
923 {
924 int sock = 0, i, ret, pollfd;
925 uint32_t revents, nb_fd;
926 enum lttcomm_return_code code;
927 struct lttng_poll_event events;
928 struct consumer_data *consumer_data = data;
929
930 DBG("[thread] Manage consumer started");
931
932 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
933 if (ret < 0) {
934 goto error;
935 }
936
937 /*
938 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
939 * Nothing more will be added to this poll set.
940 */
941 ret = create_thread_poll_set(&events, 2);
942 if (ret < 0) {
943 goto error;
944 }
945
946 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
947 if (ret < 0) {
948 goto error;
949 }
950
951 nb_fd = LTTNG_POLL_GETNB(&events);
952
953 /* Inifinite blocking call, waiting for transmission */
954 ret = lttng_poll_wait(&events, -1);
955 if (ret < 0) {
956 goto error;
957 }
958
959 for (i = 0; i < nb_fd; i++) {
960 /* Fetch once the poll data */
961 revents = LTTNG_POLL_GETEV(&events, i);
962 pollfd = LTTNG_POLL_GETFD(&events, i);
963
964 /* Thread quit pipe has been closed. Killing thread. */
965 ret = check_thread_quit_pipe(pollfd, revents);
966 if (ret) {
967 goto error;
968 }
969
970 /* Event on the registration socket */
971 if (pollfd == consumer_data->err_sock) {
972 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
973 ERR("consumer err socket poll error");
974 goto error;
975 }
976 }
977 }
978
979 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
980 if (sock < 0) {
981 goto error;
982 }
983
984 DBG2("Receiving code from consumer err_sock");
985
986 /* Getting status code from kconsumerd */
987 ret = lttcomm_recv_unix_sock(sock, &code,
988 sizeof(enum lttcomm_return_code));
989 if (ret <= 0) {
990 goto error;
991 }
992
993 if (code == CONSUMERD_COMMAND_SOCK_READY) {
994 consumer_data->cmd_sock =
995 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
996 if (consumer_data->cmd_sock < 0) {
997 sem_post(&consumer_data->sem);
998 PERROR("consumer connect");
999 goto error;
1000 }
1001 /* Signal condition to tell that the kconsumerd is ready */
1002 sem_post(&consumer_data->sem);
1003 DBG("consumer command socket ready");
1004 } else {
1005 ERR("consumer error when waiting for SOCK_READY : %s",
1006 lttcomm_get_readable_code(-code));
1007 goto error;
1008 }
1009
1010 /* Remove the kconsumerd error sock since we've established a connexion */
1011 ret = lttng_poll_del(&events, consumer_data->err_sock);
1012 if (ret < 0) {
1013 goto error;
1014 }
1015
1016 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1017 if (ret < 0) {
1018 goto error;
1019 }
1020
1021 /* Update number of fd */
1022 nb_fd = LTTNG_POLL_GETNB(&events);
1023
1024 /* Inifinite blocking call, waiting for transmission */
1025 ret = lttng_poll_wait(&events, -1);
1026 if (ret < 0) {
1027 goto error;
1028 }
1029
1030 for (i = 0; i < nb_fd; i++) {
1031 /* Fetch once the poll data */
1032 revents = LTTNG_POLL_GETEV(&events, i);
1033 pollfd = LTTNG_POLL_GETFD(&events, i);
1034
1035 /* Thread quit pipe has been closed. Killing thread. */
1036 ret = check_thread_quit_pipe(pollfd, revents);
1037 if (ret) {
1038 goto error;
1039 }
1040
1041 /* Event on the kconsumerd socket */
1042 if (pollfd == sock) {
1043 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1044 ERR("consumer err socket second poll error");
1045 goto error;
1046 }
1047 }
1048 }
1049
1050 /* Wait for any kconsumerd error */
1051 ret = lttcomm_recv_unix_sock(sock, &code,
1052 sizeof(enum lttcomm_return_code));
1053 if (ret <= 0) {
1054 ERR("consumer closed the command socket");
1055 goto error;
1056 }
1057
1058 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1059
1060 error:
1061 DBG("consumer thread dying");
1062 close(consumer_data->err_sock);
1063 close(consumer_data->cmd_sock);
1064 close(sock);
1065
1066 unlink(consumer_data->err_unix_sock_path);
1067 unlink(consumer_data->cmd_unix_sock_path);
1068 consumer_data->pid = 0;
1069
1070 lttng_poll_clean(&events);
1071
1072 return NULL;
1073 }
1074
1075 /*
1076 * This thread manage application communication.
1077 */
1078 static void *thread_manage_apps(void *data)
1079 {
1080 int i, ret, pollfd;
1081 uint32_t revents, nb_fd;
1082 struct ust_command ust_cmd;
1083 struct lttng_poll_event events;
1084
1085 DBG("[thread] Manage application started");
1086
1087 rcu_register_thread();
1088 rcu_thread_online();
1089
1090 ret = create_thread_poll_set(&events, 2);
1091 if (ret < 0) {
1092 goto error;
1093 }
1094
1095 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1096 if (ret < 0) {
1097 goto error;
1098 }
1099
1100 while (1) {
1101 /* Zeroed the events structure */
1102 lttng_poll_reset(&events);
1103
1104 nb_fd = LTTNG_POLL_GETNB(&events);
1105
1106 DBG("Apps thread polling on %d fds", nb_fd);
1107
1108 /* Inifinite blocking call, waiting for transmission */
1109 ret = lttng_poll_wait(&events, -1);
1110 if (ret < 0) {
1111 goto error;
1112 }
1113
1114 for (i = 0; i < nb_fd; i++) {
1115 /* Fetch once the poll data */
1116 revents = LTTNG_POLL_GETEV(&events, i);
1117 pollfd = LTTNG_POLL_GETFD(&events, i);
1118
1119 /* Thread quit pipe has been closed. Killing thread. */
1120 ret = check_thread_quit_pipe(pollfd, revents);
1121 if (ret) {
1122 goto error;
1123 }
1124
1125 /* Inspect the apps cmd pipe */
1126 if (pollfd == apps_cmd_pipe[0]) {
1127 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1128 ERR("Apps command pipe error");
1129 goto error;
1130 } else if (revents & LPOLLIN) {
1131 /* Empty pipe */
1132 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1133 if (ret < 0 || ret < sizeof(ust_cmd)) {
1134 perror("read apps cmd pipe");
1135 goto error;
1136 }
1137
1138 /* Register applicaton to the session daemon */
1139 ret = ust_app_register(&ust_cmd.reg_msg,
1140 ust_cmd.sock);
1141 if (ret == -ENOMEM) {
1142 goto error;
1143 } else if (ret < 0) {
1144 break;
1145 }
1146
1147 /*
1148 * Add channel(s) and event(s) to newly registered apps
1149 * from lttng global UST domain.
1150 */
1151 update_ust_app(ust_cmd.sock);
1152
1153 ret = ust_app_register_done(ust_cmd.sock);
1154 if (ret < 0) {
1155 /*
1156 * If the registration is not possible, we simply
1157 * unregister the apps and continue
1158 */
1159 ust_app_unregister(ust_cmd.sock);
1160 } else {
1161 /*
1162 * We just need here to monitor the close of the UST
1163 * socket and poll set monitor those by default.
1164 */
1165 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1166 if (ret < 0) {
1167 goto error;
1168 }
1169
1170 DBG("Apps with sock %d added to poll set",
1171 ust_cmd.sock);
1172 }
1173
1174 break;
1175 }
1176 } else {
1177 /*
1178 * At this point, we know that a registered application made
1179 * the event at poll_wait.
1180 */
1181 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1182 /* Removing from the poll set */
1183 ret = lttng_poll_del(&events, pollfd);
1184 if (ret < 0) {
1185 goto error;
1186 }
1187
1188 /* Socket closed on remote end. */
1189 ust_app_unregister(pollfd);
1190 break;
1191 }
1192 }
1193 }
1194 }
1195
1196 error:
1197 DBG("Application communication apps dying");
1198 close(apps_cmd_pipe[0]);
1199 close(apps_cmd_pipe[1]);
1200
1201 lttng_poll_clean(&events);
1202
1203 rcu_thread_offline();
1204 rcu_unregister_thread();
1205 return NULL;
1206 }
1207
1208 /*
1209 * Dispatch request from the registration threads to the application
1210 * communication thread.
1211 */
1212 static void *thread_dispatch_ust_registration(void *data)
1213 {
1214 int ret;
1215 struct cds_wfq_node *node;
1216 struct ust_command *ust_cmd = NULL;
1217
1218 DBG("[thread] Dispatch UST command started");
1219
1220 while (!dispatch_thread_exit) {
1221 /* Atomically prepare the queue futex */
1222 futex_nto1_prepare(&ust_cmd_queue.futex);
1223
1224 do {
1225 /* Dequeue command for registration */
1226 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1227 if (node == NULL) {
1228 DBG("Woken up but nothing in the UST command queue");
1229 /* Continue thread execution */
1230 break;
1231 }
1232
1233 ust_cmd = caa_container_of(node, struct ust_command, node);
1234
1235 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1236 " gid:%d sock:%d name:%s (version %d.%d)",
1237 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1238 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1239 ust_cmd->sock, ust_cmd->reg_msg.name,
1240 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1241 /*
1242 * Inform apps thread of the new application registration. This
1243 * call is blocking so we can be assured that the data will be read
1244 * at some point in time or wait to the end of the world :)
1245 */
1246 ret = write(apps_cmd_pipe[1], ust_cmd,
1247 sizeof(struct ust_command));
1248 if (ret < 0) {
1249 perror("write apps cmd pipe");
1250 if (errno == EBADF) {
1251 /*
1252 * We can't inform the application thread to process
1253 * registration. We will exit or else application
1254 * registration will not occur and tracing will never
1255 * start.
1256 */
1257 goto error;
1258 }
1259 }
1260 free(ust_cmd);
1261 } while (node != NULL);
1262
1263 /* Futex wait on queue. Blocking call on futex() */
1264 futex_nto1_wait(&ust_cmd_queue.futex);
1265 }
1266
1267 error:
1268 DBG("Dispatch thread dying");
1269 return NULL;
1270 }
1271
1272 /*
1273 * This thread manage application registration.
1274 */
1275 static void *thread_registration_apps(void *data)
1276 {
1277 int sock = 0, i, ret, pollfd;
1278 uint32_t revents, nb_fd;
1279 struct lttng_poll_event events;
1280 /*
1281 * Get allocated in this thread, enqueued to a global queue, dequeued and
1282 * freed in the manage apps thread.
1283 */
1284 struct ust_command *ust_cmd = NULL;
1285
1286 DBG("[thread] Manage application registration started");
1287
1288 ret = lttcomm_listen_unix_sock(apps_sock);
1289 if (ret < 0) {
1290 goto error;
1291 }
1292
1293 /*
1294 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1295 * more will be added to this poll set.
1296 */
1297 ret = create_thread_poll_set(&events, 2);
1298 if (ret < 0) {
1299 goto error;
1300 }
1301
1302 /* Add the application registration socket */
1303 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1304 if (ret < 0) {
1305 goto error;
1306 }
1307
1308 /* Notify all applications to register */
1309 ret = notify_ust_apps(1);
1310 if (ret < 0) {
1311 ERR("Failed to notify applications or create the wait shared memory.\n"
1312 "Execution continues but there might be problem for already\n"
1313 "running applications that wishes to register.");
1314 }
1315
1316 while (1) {
1317 DBG("Accepting application registration");
1318
1319 nb_fd = LTTNG_POLL_GETNB(&events);
1320
1321 /* Inifinite blocking call, waiting for transmission */
1322 ret = lttng_poll_wait(&events, -1);
1323 if (ret < 0) {
1324 goto error;
1325 }
1326
1327 for (i = 0; i < nb_fd; i++) {
1328 /* Fetch once the poll data */
1329 revents = LTTNG_POLL_GETEV(&events, i);
1330 pollfd = LTTNG_POLL_GETFD(&events, i);
1331
1332 /* Thread quit pipe has been closed. Killing thread. */
1333 ret = check_thread_quit_pipe(pollfd, revents);
1334 if (ret) {
1335 goto error;
1336 }
1337
1338 /* Event on the registration socket */
1339 if (pollfd == apps_sock) {
1340 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1341 ERR("Register apps socket poll error");
1342 goto error;
1343 } else if (revents & LPOLLIN) {
1344 sock = lttcomm_accept_unix_sock(apps_sock);
1345 if (sock < 0) {
1346 goto error;
1347 }
1348
1349 /* Create UST registration command for enqueuing */
1350 ust_cmd = zmalloc(sizeof(struct ust_command));
1351 if (ust_cmd == NULL) {
1352 perror("ust command zmalloc");
1353 goto error;
1354 }
1355
1356 /*
1357 * Using message-based transmissions to ensure we don't
1358 * have to deal with partially received messages.
1359 */
1360 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1361 sizeof(struct ust_register_msg));
1362 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1363 if (ret < 0) {
1364 perror("lttcomm_recv_unix_sock register apps");
1365 } else {
1366 ERR("Wrong size received on apps register");
1367 }
1368 free(ust_cmd);
1369 close(sock);
1370 continue;
1371 }
1372
1373 ust_cmd->sock = sock;
1374
1375 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1376 " gid:%d sock:%d name:%s (version %d.%d)",
1377 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1378 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1379 ust_cmd->sock, ust_cmd->reg_msg.name,
1380 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1381
1382 /*
1383 * Lock free enqueue the registration request. The red pill
1384 * has been taken! This apps will be part of the *system*.
1385 */
1386 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1387
1388 /*
1389 * Wake the registration queue futex. Implicit memory
1390 * barrier with the exchange in cds_wfq_enqueue.
1391 */
1392 futex_nto1_wake(&ust_cmd_queue.futex);
1393 }
1394 }
1395 }
1396 }
1397
1398 error:
1399 DBG("UST Registration thread dying");
1400
1401 /* Notify that the registration thread is gone */
1402 notify_ust_apps(0);
1403
1404 close(apps_sock);
1405 close(sock);
1406 unlink(apps_unix_sock_path);
1407
1408 lttng_poll_clean(&events);
1409
1410 return NULL;
1411 }
1412
1413 /*
1414 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1415 * exec or it will fails.
1416 */
1417 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1418 {
1419 int ret;
1420 struct timespec timeout;
1421
1422 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1423 timeout.tv_nsec = 0;
1424
1425 /* Setup semaphore */
1426 ret = sem_init(&consumer_data->sem, 0, 0);
1427 if (ret < 0) {
1428 PERROR("sem_init consumer semaphore");
1429 goto error;
1430 }
1431
1432 ret = pthread_create(&consumer_data->thread, NULL,
1433 thread_manage_consumer, consumer_data);
1434 if (ret != 0) {
1435 PERROR("pthread_create consumer");
1436 ret = -1;
1437 goto error;
1438 }
1439
1440 /* Get time for sem_timedwait absolute timeout */
1441 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1442 if (ret < 0) {
1443 PERROR("clock_gettime spawn consumer");
1444 /* Infinite wait for the kconsumerd thread to be ready */
1445 ret = sem_wait(&consumer_data->sem);
1446 } else {
1447 /* Normal timeout if the gettime was successful */
1448 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1449 ret = sem_timedwait(&consumer_data->sem, &timeout);
1450 }
1451
1452 if (ret < 0) {
1453 if (errno == ETIMEDOUT) {
1454 /*
1455 * Call has timed out so we kill the kconsumerd_thread and return
1456 * an error.
1457 */
1458 ERR("The consumer thread was never ready. Killing it");
1459 ret = pthread_cancel(consumer_data->thread);
1460 if (ret < 0) {
1461 PERROR("pthread_cancel consumer thread");
1462 }
1463 } else {
1464 PERROR("semaphore wait failed consumer thread");
1465 }
1466 goto error;
1467 }
1468
1469 pthread_mutex_lock(&consumer_data->pid_mutex);
1470 if (consumer_data->pid == 0) {
1471 ERR("Kconsumerd did not start");
1472 pthread_mutex_unlock(&consumer_data->pid_mutex);
1473 goto error;
1474 }
1475 pthread_mutex_unlock(&consumer_data->pid_mutex);
1476
1477 return 0;
1478
1479 error:
1480 return ret;
1481 }
1482
1483 /*
1484 * Join consumer thread
1485 */
1486 static int join_consumer_thread(struct consumer_data *consumer_data)
1487 {
1488 void *status;
1489 int ret;
1490
1491 if (consumer_data->pid != 0) {
1492 ret = kill(consumer_data->pid, SIGTERM);
1493 if (ret) {
1494 ERR("Error killing consumer daemon");
1495 return ret;
1496 }
1497 return pthread_join(consumer_data->thread, &status);
1498 } else {
1499 return 0;
1500 }
1501 }
1502
1503 /*
1504 * Fork and exec a consumer daemon (consumerd).
1505 *
1506 * Return pid if successful else -1.
1507 */
1508 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1509 {
1510 int ret;
1511 pid_t pid;
1512 const char *consumer_to_use;
1513 const char *verbosity;
1514 struct stat st;
1515
1516 DBG("Spawning consumerd");
1517
1518 pid = fork();
1519 if (pid == 0) {
1520 /*
1521 * Exec consumerd.
1522 */
1523 if (opt_verbose_consumer) {
1524 verbosity = "--verbose";
1525 } else {
1526 verbosity = "--quiet";
1527 }
1528 switch (consumer_data->type) {
1529 case LTTNG_CONSUMER_KERNEL:
1530 /*
1531 * Find out which consumerd to execute. We will first try the
1532 * 64-bit path, then the sessiond's installation directory, and
1533 * fallback on the 32-bit one,
1534 */
1535 DBG3("Looking for a kernel consumer at these locations:");
1536 DBG3(" 1) %s", consumerd64_bin);
1537 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1538 DBG3(" 3) %s", consumerd32_bin);
1539 if (stat(consumerd64_bin, &st) == 0) {
1540 DBG3("Found location #1");
1541 consumer_to_use = consumerd64_bin;
1542 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1543 DBG3("Found location #2");
1544 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1545 } else if (stat(consumerd32_bin, &st) == 0) {
1546 DBG3("Found location #3");
1547 consumer_to_use = consumerd32_bin;
1548 } else {
1549 DBG("Could not find any valid consumerd executable");
1550 break;
1551 }
1552 DBG("Using kernel consumer at: %s", consumer_to_use);
1553 execl(consumer_to_use,
1554 "lttng-consumerd", verbosity, "-k",
1555 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1556 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1557 NULL);
1558 break;
1559 case LTTNG_CONSUMER64_UST:
1560 {
1561 char *tmpnew = NULL;
1562
1563 if (consumerd64_libdir[0] != '\0') {
1564 char *tmp;
1565 size_t tmplen;
1566
1567 tmp = getenv("LD_LIBRARY_PATH");
1568 if (!tmp) {
1569 tmp = "";
1570 }
1571 tmplen = strlen("LD_LIBRARY_PATH=")
1572 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1573 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1574 if (!tmpnew) {
1575 ret = -ENOMEM;
1576 goto error;
1577 }
1578 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1579 strcat(tmpnew, consumerd64_libdir);
1580 if (tmp[0] != '\0') {
1581 strcat(tmpnew, ":");
1582 strcat(tmpnew, tmp);
1583 }
1584 ret = putenv(tmpnew);
1585 if (ret) {
1586 ret = -errno;
1587 goto error;
1588 }
1589 }
1590 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1591 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1592 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1593 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1594 NULL);
1595 if (consumerd64_libdir[0] != '\0') {
1596 free(tmpnew);
1597 }
1598 if (ret) {
1599 goto error;
1600 }
1601 break;
1602 }
1603 case LTTNG_CONSUMER32_UST:
1604 {
1605 char *tmpnew = NULL;
1606
1607 if (consumerd32_libdir[0] != '\0') {
1608 char *tmp;
1609 size_t tmplen;
1610
1611 tmp = getenv("LD_LIBRARY_PATH");
1612 if (!tmp) {
1613 tmp = "";
1614 }
1615 tmplen = strlen("LD_LIBRARY_PATH=")
1616 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1617 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1618 if (!tmpnew) {
1619 ret = -ENOMEM;
1620 goto error;
1621 }
1622 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1623 strcat(tmpnew, consumerd32_libdir);
1624 if (tmp[0] != '\0') {
1625 strcat(tmpnew, ":");
1626 strcat(tmpnew, tmp);
1627 }
1628 ret = putenv(tmpnew);
1629 if (ret) {
1630 ret = -errno;
1631 goto error;
1632 }
1633 }
1634 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1635 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1636 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1637 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1638 NULL);
1639 if (consumerd32_libdir[0] != '\0') {
1640 free(tmpnew);
1641 }
1642 if (ret) {
1643 goto error;
1644 }
1645 break;
1646 }
1647 default:
1648 perror("unknown consumer type");
1649 exit(EXIT_FAILURE);
1650 }
1651 if (errno != 0) {
1652 perror("kernel start consumer exec");
1653 }
1654 exit(EXIT_FAILURE);
1655 } else if (pid > 0) {
1656 ret = pid;
1657 } else {
1658 perror("start consumer fork");
1659 ret = -errno;
1660 }
1661 error:
1662 return ret;
1663 }
1664
1665 /*
1666 * Spawn the consumerd daemon and session daemon thread.
1667 */
1668 static int start_consumerd(struct consumer_data *consumer_data)
1669 {
1670 int ret;
1671
1672 pthread_mutex_lock(&consumer_data->pid_mutex);
1673 if (consumer_data->pid != 0) {
1674 pthread_mutex_unlock(&consumer_data->pid_mutex);
1675 goto end;
1676 }
1677
1678 ret = spawn_consumerd(consumer_data);
1679 if (ret < 0) {
1680 ERR("Spawning consumerd failed");
1681 pthread_mutex_unlock(&consumer_data->pid_mutex);
1682 goto error;
1683 }
1684
1685 /* Setting up the consumer_data pid */
1686 consumer_data->pid = ret;
1687 DBG2("Consumer pid %d", consumer_data->pid);
1688 pthread_mutex_unlock(&consumer_data->pid_mutex);
1689
1690 DBG2("Spawning consumer control thread");
1691 ret = spawn_consumer_thread(consumer_data);
1692 if (ret < 0) {
1693 ERR("Fatal error spawning consumer control thread");
1694 goto error;
1695 }
1696
1697 end:
1698 return 0;
1699
1700 error:
1701 return ret;
1702 }
1703
1704 /*
1705 * modprobe_kernel_modules
1706 */
1707 static int modprobe_kernel_modules(void)
1708 {
1709 int ret = 0, i;
1710 char modprobe[256];
1711
1712 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1713 ret = snprintf(modprobe, sizeof(modprobe),
1714 "/sbin/modprobe %s%s",
1715 kernel_modules_list[i].required ? "" : "-q ",
1716 kernel_modules_list[i].name);
1717 if (ret < 0) {
1718 perror("snprintf modprobe");
1719 goto error;
1720 }
1721 modprobe[sizeof(modprobe) - 1] = '\0';
1722 ret = system(modprobe);
1723 if (ret == -1) {
1724 ERR("Unable to launch modprobe for module %s",
1725 kernel_modules_list[i].name);
1726 } else if (kernel_modules_list[i].required
1727 && WEXITSTATUS(ret) != 0) {
1728 ERR("Unable to load module %s",
1729 kernel_modules_list[i].name);
1730 } else {
1731 DBG("Modprobe successfully %s",
1732 kernel_modules_list[i].name);
1733 }
1734 }
1735
1736 error:
1737 return ret;
1738 }
1739
1740 /*
1741 * mount_debugfs
1742 */
1743 static int mount_debugfs(char *path)
1744 {
1745 int ret;
1746 char *type = "debugfs";
1747
1748 ret = run_as_mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1749 if (ret < 0) {
1750 PERROR("Cannot create debugfs path");
1751 goto error;
1752 }
1753
1754 ret = mount(type, path, type, 0, NULL);
1755 if (ret < 0) {
1756 PERROR("Cannot mount debugfs");
1757 goto error;
1758 }
1759
1760 DBG("Mounted debugfs successfully at %s", path);
1761
1762 error:
1763 return ret;
1764 }
1765
1766 /*
1767 * Setup necessary data for kernel tracer action.
1768 */
1769 static void init_kernel_tracer(void)
1770 {
1771 int ret;
1772 char *proc_mounts = "/proc/mounts";
1773 char line[256];
1774 char *debugfs_path = NULL, *lttng_path = NULL;
1775 FILE *fp;
1776
1777 /* Detect debugfs */
1778 fp = fopen(proc_mounts, "r");
1779 if (fp == NULL) {
1780 ERR("Unable to probe %s", proc_mounts);
1781 goto error;
1782 }
1783
1784 while (fgets(line, sizeof(line), fp) != NULL) {
1785 if (strstr(line, "debugfs") != NULL) {
1786 /* Remove first string */
1787 strtok(line, " ");
1788 /* Dup string here so we can reuse line later on */
1789 debugfs_path = strdup(strtok(NULL, " "));
1790 DBG("Got debugfs path : %s", debugfs_path);
1791 break;
1792 }
1793 }
1794
1795 fclose(fp);
1796
1797 /* Mount debugfs if needded */
1798 if (debugfs_path == NULL) {
1799 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1800 if (ret < 0) {
1801 perror("asprintf debugfs path");
1802 goto error;
1803 }
1804 ret = mount_debugfs(debugfs_path);
1805 if (ret < 0) {
1806 perror("Cannot mount debugfs");
1807 goto error;
1808 }
1809 }
1810
1811 /* Modprobe lttng kernel modules */
1812 ret = modprobe_kernel_modules();
1813 if (ret < 0) {
1814 goto error;
1815 }
1816
1817 /* Setup lttng kernel path */
1818 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1819 if (ret < 0) {
1820 perror("asprintf lttng path");
1821 goto error;
1822 }
1823
1824 /* Open debugfs lttng */
1825 kernel_tracer_fd = open(lttng_path, O_RDWR);
1826 if (kernel_tracer_fd < 0) {
1827 DBG("Failed to open %s", lttng_path);
1828 goto error;
1829 }
1830
1831 free(lttng_path);
1832 free(debugfs_path);
1833 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1834 return;
1835
1836 error:
1837 if (lttng_path) {
1838 free(lttng_path);
1839 }
1840 if (debugfs_path) {
1841 free(debugfs_path);
1842 }
1843 WARN("No kernel tracer available");
1844 kernel_tracer_fd = 0;
1845 return;
1846 }
1847
1848 /*
1849 * Init tracing by creating trace directory and sending fds kernel consumer.
1850 */
1851 static int init_kernel_tracing(struct ltt_kernel_session *session)
1852 {
1853 int ret = 0;
1854
1855 if (session->consumer_fds_sent == 0) {
1856 /*
1857 * Assign default kernel consumer socket if no consumer assigned to the
1858 * kernel session. At this point, it's NOT suppose to be 0 but this is
1859 * an extra security check.
1860 */
1861 if (session->consumer_fd == 0) {
1862 session->consumer_fd = kconsumer_data.cmd_sock;
1863 }
1864
1865 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1866 if (ret < 0) {
1867 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1868 goto error;
1869 }
1870
1871 session->consumer_fds_sent = 1;
1872 }
1873
1874 error:
1875 return ret;
1876 }
1877
1878 /*
1879 * Create an UST session and add it to the session ust list.
1880 */
1881 static int create_ust_session(struct ltt_session *session,
1882 struct lttng_domain *domain)
1883 {
1884 struct ltt_ust_session *lus = NULL;
1885 int ret;
1886
1887 switch (domain->type) {
1888 case LTTNG_DOMAIN_UST:
1889 break;
1890 default:
1891 ret = LTTCOMM_UNKNOWN_DOMAIN;
1892 goto error;
1893 }
1894
1895 DBG("Creating UST session");
1896
1897 lus = trace_ust_create_session(session->path, session->id, domain);
1898 if (lus == NULL) {
1899 ret = LTTCOMM_UST_SESS_FAIL;
1900 goto error;
1901 }
1902
1903 ret = run_as_mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1904 session->uid, session->gid);
1905 if (ret < 0) {
1906 if (ret != -EEXIST) {
1907 ERR("Trace directory creation error");
1908 ret = LTTCOMM_UST_SESS_FAIL;
1909 goto error;
1910 }
1911 }
1912
1913 /* The domain type dictate different actions on session creation */
1914 switch (domain->type) {
1915 case LTTNG_DOMAIN_UST:
1916 /* No ustctl for the global UST domain */
1917 break;
1918 default:
1919 ERR("Unknown UST domain on create session %d", domain->type);
1920 goto error;
1921 }
1922 lus->uid = session->uid;
1923 lus->gid = session->gid;
1924 session->ust_session = lus;
1925
1926 return LTTCOMM_OK;
1927
1928 error:
1929 free(lus);
1930 return ret;
1931 }
1932
1933 /*
1934 * Create a kernel tracer session then create the default channel.
1935 */
1936 static int create_kernel_session(struct ltt_session *session)
1937 {
1938 int ret;
1939
1940 DBG("Creating kernel session");
1941
1942 ret = kernel_create_session(session, kernel_tracer_fd);
1943 if (ret < 0) {
1944 ret = LTTCOMM_KERN_SESS_FAIL;
1945 goto error;
1946 }
1947
1948 /* Set kernel consumer socket fd */
1949 if (kconsumer_data.cmd_sock) {
1950 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1951 }
1952
1953 ret = run_as_mkdir_recursive(session->kernel_session->trace_path,
1954 S_IRWXU | S_IRWXG, session->uid, session->gid);
1955 if (ret < 0) {
1956 if (ret != -EEXIST) {
1957 ERR("Trace directory creation error");
1958 goto error;
1959 }
1960 }
1961 session->kernel_session->uid = session->uid;
1962 session->kernel_session->gid = session->gid;
1963
1964 error:
1965 return ret;
1966 }
1967
1968 /*
1969 * Check if the UID or GID match the session. Root user has access to all
1970 * sessions.
1971 */
1972 static int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid)
1973 {
1974 if (uid != session->uid && gid != session->gid && uid != 0) {
1975 return 0;
1976 } else {
1977 return 1;
1978 }
1979 }
1980
1981 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
1982 {
1983 unsigned int i = 0;
1984 struct ltt_session *session;
1985
1986 DBG("Counting number of available session for UID %d GID %d",
1987 uid, gid);
1988 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1989 /*
1990 * Only list the sessions the user can control.
1991 */
1992 if (!session_access_ok(session, uid, gid)) {
1993 continue;
1994 }
1995 i++;
1996 }
1997 return i;
1998 }
1999
2000 /*
2001 * Using the session list, filled a lttng_session array to send back to the
2002 * client for session listing.
2003 *
2004 * The session list lock MUST be acquired before calling this function. Use
2005 * session_lock_list() and session_unlock_list().
2006 */
2007 static void list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2008 gid_t gid)
2009 {
2010 unsigned int i = 0;
2011 struct ltt_session *session;
2012
2013 DBG("Getting all available session for UID %d GID %d",
2014 uid, gid);
2015 /*
2016 * Iterate over session list and append data after the control struct in
2017 * the buffer.
2018 */
2019 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2020 /*
2021 * Only list the sessions the user can control.
2022 */
2023 if (!session_access_ok(session, uid, gid)) {
2024 continue;
2025 }
2026 strncpy(sessions[i].path, session->path, PATH_MAX);
2027 sessions[i].path[PATH_MAX - 1] = '\0';
2028 strncpy(sessions[i].name, session->name, NAME_MAX);
2029 sessions[i].name[NAME_MAX - 1] = '\0';
2030 sessions[i].enabled = session->enabled;
2031 i++;
2032 }
2033 }
2034
2035 /*
2036 * Fill lttng_channel array of all channels.
2037 */
2038 static void list_lttng_channels(int domain, struct ltt_session *session,
2039 struct lttng_channel *channels)
2040 {
2041 int i = 0;
2042 struct ltt_kernel_channel *kchan;
2043
2044 DBG("Listing channels for session %s", session->name);
2045
2046 switch (domain) {
2047 case LTTNG_DOMAIN_KERNEL:
2048 /* Kernel channels */
2049 if (session->kernel_session != NULL) {
2050 cds_list_for_each_entry(kchan,
2051 &session->kernel_session->channel_list.head, list) {
2052 /* Copy lttng_channel struct to array */
2053 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2054 channels[i].enabled = kchan->enabled;
2055 i++;
2056 }
2057 }
2058 break;
2059 case LTTNG_DOMAIN_UST:
2060 {
2061 struct lttng_ht_iter iter;
2062 struct ltt_ust_channel *uchan;
2063
2064 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
2065 &iter.iter, uchan, node.node) {
2066 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2067 channels[i].attr.overwrite = uchan->attr.overwrite;
2068 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2069 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2070 channels[i].attr.switch_timer_interval =
2071 uchan->attr.switch_timer_interval;
2072 channels[i].attr.read_timer_interval =
2073 uchan->attr.read_timer_interval;
2074 channels[i].enabled = uchan->enabled;
2075 switch (uchan->attr.output) {
2076 case LTTNG_UST_MMAP:
2077 default:
2078 channels[i].attr.output = LTTNG_EVENT_MMAP;
2079 break;
2080 }
2081 i++;
2082 }
2083 break;
2084 }
2085 default:
2086 break;
2087 }
2088 }
2089
2090 /*
2091 * Create a list of ust global domain events.
2092 */
2093 static int list_lttng_ust_global_events(char *channel_name,
2094 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2095 {
2096 int i = 0, ret = 0;
2097 unsigned int nb_event = 0;
2098 struct lttng_ht_iter iter;
2099 struct lttng_ht_node_str *node;
2100 struct ltt_ust_channel *uchan;
2101 struct ltt_ust_event *uevent;
2102 struct lttng_event *tmp;
2103
2104 DBG("Listing UST global events for channel %s", channel_name);
2105
2106 rcu_read_lock();
2107
2108 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2109 node = lttng_ht_iter_get_node_str(&iter);
2110 if (node == NULL) {
2111 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2112 goto error;
2113 }
2114
2115 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2116
2117 nb_event += lttng_ht_get_count(uchan->events);
2118
2119 if (nb_event == 0) {
2120 ret = nb_event;
2121 goto error;
2122 }
2123
2124 DBG3("Listing UST global %d events", nb_event);
2125
2126 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2127 if (tmp == NULL) {
2128 ret = -LTTCOMM_FATAL;
2129 goto error;
2130 }
2131
2132 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2133 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2134 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2135 tmp[i].enabled = uevent->enabled;
2136 switch (uevent->attr.instrumentation) {
2137 case LTTNG_UST_TRACEPOINT:
2138 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2139 break;
2140 case LTTNG_UST_PROBE:
2141 tmp[i].type = LTTNG_EVENT_PROBE;
2142 break;
2143 case LTTNG_UST_FUNCTION:
2144 tmp[i].type = LTTNG_EVENT_FUNCTION;
2145 break;
2146 case LTTNG_UST_TRACEPOINT_LOGLEVEL:
2147 tmp[i].type = LTTNG_EVENT_TRACEPOINT_LOGLEVEL;
2148 break;
2149 }
2150 i++;
2151 }
2152
2153 ret = nb_event;
2154 *events = tmp;
2155
2156 error:
2157 rcu_read_unlock();
2158 return ret;
2159 }
2160
2161 /*
2162 * Fill lttng_event array of all kernel events in the channel.
2163 */
2164 static int list_lttng_kernel_events(char *channel_name,
2165 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2166 {
2167 int i = 0, ret;
2168 unsigned int nb_event;
2169 struct ltt_kernel_event *event;
2170 struct ltt_kernel_channel *kchan;
2171
2172 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2173 if (kchan == NULL) {
2174 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2175 goto error;
2176 }
2177
2178 nb_event = kchan->event_count;
2179
2180 DBG("Listing events for channel %s", kchan->channel->name);
2181
2182 if (nb_event == 0) {
2183 ret = nb_event;
2184 goto error;
2185 }
2186
2187 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2188 if (*events == NULL) {
2189 ret = LTTCOMM_FATAL;
2190 goto error;
2191 }
2192
2193 /* Kernel channels */
2194 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2195 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2196 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2197 (*events)[i].enabled = event->enabled;
2198 switch (event->event->instrumentation) {
2199 case LTTNG_KERNEL_TRACEPOINT:
2200 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2201 break;
2202 case LTTNG_KERNEL_KPROBE:
2203 case LTTNG_KERNEL_KRETPROBE:
2204 (*events)[i].type = LTTNG_EVENT_PROBE;
2205 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2206 sizeof(struct lttng_kernel_kprobe));
2207 break;
2208 case LTTNG_KERNEL_FUNCTION:
2209 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2210 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2211 sizeof(struct lttng_kernel_function));
2212 break;
2213 case LTTNG_KERNEL_NOOP:
2214 (*events)[i].type = LTTNG_EVENT_NOOP;
2215 break;
2216 case LTTNG_KERNEL_SYSCALL:
2217 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2218 break;
2219 case LTTNG_KERNEL_ALL:
2220 assert(0);
2221 break;
2222 }
2223 i++;
2224 }
2225
2226 return nb_event;
2227
2228 error:
2229 return ret;
2230 }
2231
2232 /*
2233 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2234 */
2235 static int cmd_disable_channel(struct ltt_session *session,
2236 int domain, char *channel_name)
2237 {
2238 int ret;
2239 struct ltt_ust_session *usess;
2240
2241 usess = session->ust_session;
2242
2243 switch (domain) {
2244 case LTTNG_DOMAIN_KERNEL:
2245 {
2246 ret = channel_kernel_disable(session->kernel_session,
2247 channel_name);
2248 if (ret != LTTCOMM_OK) {
2249 goto error;
2250 }
2251
2252 kernel_wait_quiescent(kernel_tracer_fd);
2253 break;
2254 }
2255 case LTTNG_DOMAIN_UST:
2256 {
2257 struct ltt_ust_channel *uchan;
2258 struct lttng_ht *chan_ht;
2259
2260 chan_ht = usess->domain_global.channels;
2261
2262 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2263 if (uchan == NULL) {
2264 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2265 goto error;
2266 }
2267
2268 ret = channel_ust_disable(usess, domain, uchan);
2269 if (ret != LTTCOMM_OK) {
2270 goto error;
2271 }
2272 break;
2273 }
2274 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2275 case LTTNG_DOMAIN_UST_EXEC_NAME:
2276 case LTTNG_DOMAIN_UST_PID:
2277 ret = LTTCOMM_NOT_IMPLEMENTED;
2278 goto error;
2279 default:
2280 ret = LTTCOMM_UNKNOWN_DOMAIN;
2281 goto error;
2282 }
2283
2284 ret = LTTCOMM_OK;
2285
2286 error:
2287 return ret;
2288 }
2289
2290 /*
2291 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2292 */
2293 static int cmd_enable_channel(struct ltt_session *session,
2294 int domain, struct lttng_channel *attr)
2295 {
2296 int ret;
2297 struct ltt_ust_session *usess = session->ust_session;
2298 struct lttng_ht *chan_ht;
2299
2300 DBG("Enabling channel %s for session %s", attr->name, session->name);
2301
2302 switch (domain) {
2303 case LTTNG_DOMAIN_KERNEL:
2304 {
2305 struct ltt_kernel_channel *kchan;
2306
2307 kchan = trace_kernel_get_channel_by_name(attr->name,
2308 session->kernel_session);
2309 if (kchan == NULL) {
2310 ret = channel_kernel_create(session->kernel_session,
2311 attr, kernel_poll_pipe[1]);
2312 } else {
2313 ret = channel_kernel_enable(session->kernel_session, kchan);
2314 }
2315
2316 if (ret != LTTCOMM_OK) {
2317 goto error;
2318 }
2319
2320 kernel_wait_quiescent(kernel_tracer_fd);
2321 break;
2322 }
2323 case LTTNG_DOMAIN_UST:
2324 {
2325 struct ltt_ust_channel *uchan;
2326
2327 chan_ht = usess->domain_global.channels;
2328
2329 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2330 if (uchan == NULL) {
2331 ret = channel_ust_create(usess, domain, attr);
2332 } else {
2333 ret = channel_ust_enable(usess, domain, uchan);
2334 }
2335 break;
2336 }
2337 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2338 case LTTNG_DOMAIN_UST_EXEC_NAME:
2339 case LTTNG_DOMAIN_UST_PID:
2340 ret = LTTCOMM_NOT_IMPLEMENTED;
2341 goto error;
2342 default:
2343 ret = LTTCOMM_UNKNOWN_DOMAIN;
2344 goto error;
2345 }
2346
2347 error:
2348 return ret;
2349 }
2350
2351 /*
2352 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2353 */
2354 static int cmd_disable_event(struct ltt_session *session, int domain,
2355 char *channel_name, char *event_name)
2356 {
2357 int ret;
2358
2359 switch (domain) {
2360 case LTTNG_DOMAIN_KERNEL:
2361 {
2362 struct ltt_kernel_channel *kchan;
2363 struct ltt_kernel_session *ksess;
2364
2365 ksess = session->kernel_session;
2366
2367 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2368 if (kchan == NULL) {
2369 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2370 goto error;
2371 }
2372
2373 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2374 if (ret != LTTCOMM_OK) {
2375 goto error;
2376 }
2377
2378 kernel_wait_quiescent(kernel_tracer_fd);
2379 break;
2380 }
2381 case LTTNG_DOMAIN_UST:
2382 {
2383 struct ltt_ust_channel *uchan;
2384 struct ltt_ust_session *usess;
2385
2386 usess = session->ust_session;
2387
2388 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2389 channel_name);
2390 if (uchan == NULL) {
2391 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2392 goto error;
2393 }
2394
2395 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2396 if (ret != LTTCOMM_OK) {
2397 goto error;
2398 }
2399
2400 DBG3("Disable UST event %s in channel %s completed", event_name,
2401 channel_name);
2402 break;
2403 }
2404 case LTTNG_DOMAIN_UST_EXEC_NAME:
2405 case LTTNG_DOMAIN_UST_PID:
2406 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2407 default:
2408 ret = LTTCOMM_NOT_IMPLEMENTED;
2409 goto error;
2410 }
2411
2412 ret = LTTCOMM_OK;
2413
2414 error:
2415 return ret;
2416 }
2417
2418 /*
2419 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2420 */
2421 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2422 char *channel_name)
2423 {
2424 int ret;
2425
2426 switch (domain) {
2427 case LTTNG_DOMAIN_KERNEL:
2428 {
2429 struct ltt_kernel_session *ksess;
2430 struct ltt_kernel_channel *kchan;
2431
2432 ksess = session->kernel_session;
2433
2434 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2435 if (kchan == NULL) {
2436 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2437 goto error;
2438 }
2439
2440 ret = event_kernel_disable_all(ksess, kchan);
2441 if (ret != LTTCOMM_OK) {
2442 goto error;
2443 }
2444
2445 kernel_wait_quiescent(kernel_tracer_fd);
2446 break;
2447 }
2448 case LTTNG_DOMAIN_UST:
2449 {
2450 struct ltt_ust_session *usess;
2451 struct ltt_ust_channel *uchan;
2452
2453 usess = session->ust_session;
2454
2455 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2456 channel_name);
2457 if (uchan == NULL) {
2458 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2459 goto error;
2460 }
2461
2462 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2463 if (ret != 0) {
2464 goto error;
2465 }
2466
2467 DBG3("Disable all UST events in channel %s completed", channel_name);
2468
2469 break;
2470 }
2471 case LTTNG_DOMAIN_UST_EXEC_NAME:
2472 case LTTNG_DOMAIN_UST_PID:
2473 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2474 default:
2475 ret = LTTCOMM_NOT_IMPLEMENTED;
2476 goto error;
2477 }
2478
2479 ret = LTTCOMM_OK;
2480
2481 error:
2482 return ret;
2483 }
2484
2485 /*
2486 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2487 */
2488 static int cmd_add_context(struct ltt_session *session, int domain,
2489 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2490 {
2491 int ret;
2492
2493 switch (domain) {
2494 case LTTNG_DOMAIN_KERNEL:
2495 /* Add kernel context to kernel tracer */
2496 ret = context_kernel_add(session->kernel_session, ctx,
2497 event_name, channel_name);
2498 if (ret != LTTCOMM_OK) {
2499 goto error;
2500 }
2501 break;
2502 case LTTNG_DOMAIN_UST:
2503 {
2504 struct ltt_ust_session *usess = session->ust_session;
2505
2506 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2507 if (ret != LTTCOMM_OK) {
2508 goto error;
2509 }
2510 break;
2511 }
2512 case LTTNG_DOMAIN_UST_EXEC_NAME:
2513 case LTTNG_DOMAIN_UST_PID:
2514 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2515 default:
2516 ret = LTTCOMM_NOT_IMPLEMENTED;
2517 goto error;
2518 }
2519
2520 ret = LTTCOMM_OK;
2521
2522 error:
2523 return ret;
2524 }
2525
2526 /*
2527 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2528 *
2529 * TODO: currently, both events and loglevels are kept within the same
2530 * namespace for UST global registry/app registery, so if an event
2531 * happen to have the same name as the loglevel (very unlikely though),
2532 * and an attempt is made to enable/disable both in the same session,
2533 * the first to be created will be the only one allowed to exist.
2534 */
2535 static int cmd_enable_event(struct ltt_session *session, int domain,
2536 char *channel_name, struct lttng_event *event)
2537 {
2538 int ret;
2539 struct lttng_channel *attr;
2540 struct ltt_ust_session *usess = session->ust_session;
2541
2542 switch (domain) {
2543 case LTTNG_DOMAIN_KERNEL:
2544 {
2545 struct ltt_kernel_channel *kchan;
2546
2547 kchan = trace_kernel_get_channel_by_name(channel_name,
2548 session->kernel_session);
2549 if (kchan == NULL) {
2550 attr = channel_new_default_attr(domain);
2551 if (attr == NULL) {
2552 ret = LTTCOMM_FATAL;
2553 goto error;
2554 }
2555 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2556
2557 /* This call will notify the kernel thread */
2558 ret = channel_kernel_create(session->kernel_session,
2559 attr, kernel_poll_pipe[1]);
2560 if (ret != LTTCOMM_OK) {
2561 free(attr);
2562 goto error;
2563 }
2564 free(attr);
2565 }
2566
2567 /* Get the newly created kernel channel pointer */
2568 kchan = trace_kernel_get_channel_by_name(channel_name,
2569 session->kernel_session);
2570 if (kchan == NULL) {
2571 /* This sould not happen... */
2572 ret = LTTCOMM_FATAL;
2573 goto error;
2574 }
2575
2576 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2577 event);
2578 if (ret != LTTCOMM_OK) {
2579 goto error;
2580 }
2581
2582 kernel_wait_quiescent(kernel_tracer_fd);
2583 break;
2584 }
2585 case LTTNG_DOMAIN_UST:
2586 {
2587 struct lttng_channel *attr;
2588 struct ltt_ust_channel *uchan;
2589
2590 /* Get channel from global UST domain */
2591 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2592 channel_name);
2593 if (uchan == NULL) {
2594 /* Create default channel */
2595 attr = channel_new_default_attr(domain);
2596 if (attr == NULL) {
2597 ret = LTTCOMM_FATAL;
2598 goto error;
2599 }
2600 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2601 attr->name[NAME_MAX - 1] = '\0';
2602
2603 ret = channel_ust_create(usess, domain, attr);
2604 if (ret != LTTCOMM_OK) {
2605 free(attr);
2606 goto error;
2607 }
2608 free(attr);
2609
2610 /* Get the newly created channel reference back */
2611 uchan = trace_ust_find_channel_by_name(
2612 usess->domain_global.channels, channel_name);
2613 if (uchan == NULL) {
2614 /* Something is really wrong */
2615 ret = LTTCOMM_FATAL;
2616 goto error;
2617 }
2618 }
2619
2620 /* At this point, the session and channel exist on the tracer */
2621 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2622 if (ret != LTTCOMM_OK) {
2623 goto error;
2624 }
2625 break;
2626 }
2627 case LTTNG_DOMAIN_UST_EXEC_NAME:
2628 case LTTNG_DOMAIN_UST_PID:
2629 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2630 default:
2631 ret = LTTCOMM_NOT_IMPLEMENTED;
2632 goto error;
2633 }
2634
2635 ret = LTTCOMM_OK;
2636
2637 error:
2638 return ret;
2639 }
2640
2641 /*
2642 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2643 */
2644 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2645 char *channel_name, int event_type)
2646 {
2647 int ret;
2648 struct ltt_kernel_channel *kchan;
2649
2650 switch (domain) {
2651 case LTTNG_DOMAIN_KERNEL:
2652 kchan = trace_kernel_get_channel_by_name(channel_name,
2653 session->kernel_session);
2654 if (kchan == NULL) {
2655 /* This call will notify the kernel thread */
2656 ret = channel_kernel_create(session->kernel_session, NULL,
2657 kernel_poll_pipe[1]);
2658 if (ret != LTTCOMM_OK) {
2659 goto error;
2660 }
2661
2662 /* Get the newly created kernel channel pointer */
2663 kchan = trace_kernel_get_channel_by_name(channel_name,
2664 session->kernel_session);
2665 if (kchan == NULL) {
2666 /* This sould not happen... */
2667 ret = LTTCOMM_FATAL;
2668 goto error;
2669 }
2670
2671 }
2672
2673 switch (event_type) {
2674 case LTTNG_EVENT_SYSCALL:
2675 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2676 kchan, kernel_tracer_fd);
2677 break;
2678 case LTTNG_EVENT_TRACEPOINT:
2679 /*
2680 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2681 * events already registered to the channel.
2682 */
2683 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2684 kchan, kernel_tracer_fd);
2685 break;
2686 case LTTNG_EVENT_ALL:
2687 /* Enable syscalls and tracepoints */
2688 ret = event_kernel_enable_all(session->kernel_session,
2689 kchan, kernel_tracer_fd);
2690 break;
2691 default:
2692 ret = LTTCOMM_KERN_ENABLE_FAIL;
2693 goto error;
2694 }
2695
2696 /* Manage return value */
2697 if (ret != LTTCOMM_OK) {
2698 goto error;
2699 }
2700
2701 kernel_wait_quiescent(kernel_tracer_fd);
2702 break;
2703 case LTTNG_DOMAIN_UST:
2704 {
2705 struct lttng_channel *attr;
2706 struct ltt_ust_channel *uchan;
2707 struct ltt_ust_session *usess = session->ust_session;
2708
2709 /* Get channel from global UST domain */
2710 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2711 channel_name);
2712 if (uchan == NULL) {
2713 /* Create default channel */
2714 attr = channel_new_default_attr(domain);
2715 if (attr == NULL) {
2716 ret = LTTCOMM_FATAL;
2717 goto error;
2718 }
2719 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2720 attr->name[NAME_MAX - 1] = '\0';
2721
2722 /* Use the internal command enable channel */
2723 ret = channel_ust_create(usess, domain, attr);
2724 if (ret != LTTCOMM_OK) {
2725 free(attr);
2726 goto error;
2727 }
2728 free(attr);
2729
2730 /* Get the newly created channel reference back */
2731 uchan = trace_ust_find_channel_by_name(
2732 usess->domain_global.channels, channel_name);
2733 if (uchan == NULL) {
2734 /* Something is really wrong */
2735 ret = LTTCOMM_FATAL;
2736 goto error;
2737 }
2738 }
2739
2740 /* At this point, the session and channel exist on the tracer */
2741
2742 switch (event_type) {
2743 case LTTNG_EVENT_ALL:
2744 case LTTNG_EVENT_TRACEPOINT:
2745 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2746 if (ret != LTTCOMM_OK) {
2747 goto error;
2748 }
2749 break;
2750 default:
2751 ret = LTTCOMM_UST_ENABLE_FAIL;
2752 goto error;
2753 }
2754
2755 /* Manage return value */
2756 if (ret != LTTCOMM_OK) {
2757 goto error;
2758 }
2759
2760 break;
2761 }
2762 case LTTNG_DOMAIN_UST_EXEC_NAME:
2763 case LTTNG_DOMAIN_UST_PID:
2764 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2765 default:
2766 ret = LTTCOMM_NOT_IMPLEMENTED;
2767 goto error;
2768 }
2769
2770 ret = LTTCOMM_OK;
2771
2772 error:
2773 return ret;
2774 }
2775
2776 /*
2777 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2778 */
2779 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2780 {
2781 int ret;
2782 ssize_t nb_events = 0;
2783
2784 switch (domain) {
2785 case LTTNG_DOMAIN_KERNEL:
2786 nb_events = kernel_list_events(kernel_tracer_fd, events);
2787 if (nb_events < 0) {
2788 ret = LTTCOMM_KERN_LIST_FAIL;
2789 goto error;
2790 }
2791 break;
2792 case LTTNG_DOMAIN_UST:
2793 nb_events = ust_app_list_events(events);
2794 if (nb_events < 0) {
2795 ret = LTTCOMM_UST_LIST_FAIL;
2796 goto error;
2797 }
2798 break;
2799 default:
2800 ret = LTTCOMM_NOT_IMPLEMENTED;
2801 goto error;
2802 }
2803
2804 return nb_events;
2805
2806 error:
2807 /* Return negative value to differentiate return code */
2808 return -ret;
2809 }
2810
2811 /*
2812 * Command LTTNG_START_TRACE processed by the client thread.
2813 */
2814 static int cmd_start_trace(struct ltt_session *session)
2815 {
2816 int ret;
2817 struct ltt_kernel_session *ksession;
2818 struct ltt_ust_session *usess;
2819
2820 /* Short cut */
2821 ksession = session->kernel_session;
2822 usess = session->ust_session;
2823
2824 if (session->enabled) {
2825 ret = LTTCOMM_UST_START_FAIL;
2826 goto error;
2827 }
2828
2829 session->enabled = 1;
2830
2831 /* Kernel tracing */
2832 if (ksession != NULL) {
2833 struct ltt_kernel_channel *kchan;
2834
2835 /* Open kernel metadata */
2836 if (ksession->metadata == NULL) {
2837 ret = kernel_open_metadata(ksession, ksession->trace_path);
2838 if (ret < 0) {
2839 ret = LTTCOMM_KERN_META_FAIL;
2840 goto error;
2841 }
2842 }
2843
2844 /* Open kernel metadata stream */
2845 if (ksession->metadata_stream_fd == 0) {
2846 ret = kernel_open_metadata_stream(ksession);
2847 if (ret < 0) {
2848 ERR("Kernel create metadata stream failed");
2849 ret = LTTCOMM_KERN_STREAM_FAIL;
2850 goto error;
2851 }
2852 }
2853
2854 /* For each channel */
2855 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2856 if (kchan->stream_count == 0) {
2857 ret = kernel_open_channel_stream(kchan);
2858 if (ret < 0) {
2859 ret = LTTCOMM_KERN_STREAM_FAIL;
2860 goto error;
2861 }
2862 /* Update the stream global counter */
2863 ksession->stream_count_global += ret;
2864 }
2865 }
2866
2867 /* Setup kernel consumer socket and send fds to it */
2868 ret = init_kernel_tracing(ksession);
2869 if (ret < 0) {
2870 ret = LTTCOMM_KERN_START_FAIL;
2871 goto error;
2872 }
2873
2874 /* This start the kernel tracing */
2875 ret = kernel_start_session(ksession);
2876 if (ret < 0) {
2877 ret = LTTCOMM_KERN_START_FAIL;
2878 goto error;
2879 }
2880
2881 /* Quiescent wait after starting trace */
2882 kernel_wait_quiescent(kernel_tracer_fd);
2883 }
2884
2885 /* Flag session that trace should start automatically */
2886 if (usess) {
2887 usess->start_trace = 1;
2888
2889 ret = ust_app_start_trace_all(usess);
2890 if (ret < 0) {
2891 ret = LTTCOMM_UST_START_FAIL;
2892 goto error;
2893 }
2894 }
2895
2896 ret = LTTCOMM_OK;
2897
2898 error:
2899 return ret;
2900 }
2901
2902 /*
2903 * Command LTTNG_STOP_TRACE processed by the client thread.
2904 */
2905 static int cmd_stop_trace(struct ltt_session *session)
2906 {
2907 int ret;
2908 struct ltt_kernel_channel *kchan;
2909 struct ltt_kernel_session *ksession;
2910 struct ltt_ust_session *usess;
2911
2912 /* Short cut */
2913 ksession = session->kernel_session;
2914 usess = session->ust_session;
2915
2916 if (!session->enabled) {
2917 ret = LTTCOMM_UST_STOP_FAIL;
2918 goto error;
2919 }
2920
2921 session->enabled = 0;
2922
2923 /* Kernel tracer */
2924 if (ksession != NULL) {
2925 DBG("Stop kernel tracing");
2926
2927 /* Flush all buffers before stopping */
2928 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2929 if (ret < 0) {
2930 ERR("Kernel metadata flush failed");
2931 }
2932
2933 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2934 ret = kernel_flush_buffer(kchan);
2935 if (ret < 0) {
2936 ERR("Kernel flush buffer error");
2937 }
2938 }
2939
2940 ret = kernel_stop_session(ksession);
2941 if (ret < 0) {
2942 ret = LTTCOMM_KERN_STOP_FAIL;
2943 goto error;
2944 }
2945
2946 kernel_wait_quiescent(kernel_tracer_fd);
2947 }
2948
2949 if (usess) {
2950 usess->start_trace = 0;
2951
2952 ret = ust_app_stop_trace_all(usess);
2953 if (ret < 0) {
2954 ret = LTTCOMM_UST_STOP_FAIL;
2955 goto error;
2956 }
2957 }
2958
2959 ret = LTTCOMM_OK;
2960
2961 error:
2962 return ret;
2963 }
2964
2965 /*
2966 * Command LTTNG_CREATE_SESSION processed by the client thread.
2967 */
2968 static int cmd_create_session(char *name, char *path, struct ucred *creds)
2969 {
2970 int ret;
2971
2972 ret = session_create(name, path, creds->uid, creds->gid);
2973 if (ret != LTTCOMM_OK) {
2974 goto error;
2975 }
2976
2977 ret = LTTCOMM_OK;
2978
2979 error:
2980 return ret;
2981 }
2982
2983 /*
2984 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2985 */
2986 static int cmd_destroy_session(struct ltt_session *session, char *name)
2987 {
2988 int ret;
2989
2990 /* Clean kernel session teardown */
2991 teardown_kernel_session(session);
2992 /* UST session teardown */
2993 teardown_ust_session(session);
2994
2995 /*
2996 * Must notify the kernel thread here to update it's poll setin order
2997 * to remove the channel(s)' fd just destroyed.
2998 */
2999 ret = notify_thread_pipe(kernel_poll_pipe[1]);
3000 if (ret < 0) {
3001 perror("write kernel poll pipe");
3002 }
3003
3004 ret = session_destroy(session);
3005
3006 return ret;
3007 }
3008
3009 /*
3010 * Command LTTNG_CALIBRATE processed by the client thread.
3011 */
3012 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3013 {
3014 int ret;
3015
3016 switch (domain) {
3017 case LTTNG_DOMAIN_KERNEL:
3018 {
3019 struct lttng_kernel_calibrate kcalibrate;
3020
3021 kcalibrate.type = calibrate->type;
3022 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3023 if (ret < 0) {
3024 ret = LTTCOMM_KERN_ENABLE_FAIL;
3025 goto error;
3026 }
3027 break;
3028 }
3029 default:
3030 /* TODO: Userspace tracing */
3031 ret = LTTCOMM_NOT_IMPLEMENTED;
3032 goto error;
3033 }
3034
3035 ret = LTTCOMM_OK;
3036
3037 error:
3038 return ret;
3039 }
3040
3041 /*
3042 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3043 */
3044 static int cmd_register_consumer(struct ltt_session *session, int domain,
3045 char *sock_path)
3046 {
3047 int ret, sock;
3048
3049 switch (domain) {
3050 case LTTNG_DOMAIN_KERNEL:
3051 /* Can't register a consumer if there is already one */
3052 if (session->kernel_session->consumer_fds_sent != 0) {
3053 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3054 goto error;
3055 }
3056
3057 sock = lttcomm_connect_unix_sock(sock_path);
3058 if (sock < 0) {
3059 ret = LTTCOMM_CONNECT_FAIL;
3060 goto error;
3061 }
3062
3063 session->kernel_session->consumer_fd = sock;
3064 break;
3065 default:
3066 /* TODO: Userspace tracing */
3067 ret = LTTCOMM_NOT_IMPLEMENTED;
3068 goto error;
3069 }
3070
3071 ret = LTTCOMM_OK;
3072
3073 error:
3074 return ret;
3075 }
3076
3077 /*
3078 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3079 */
3080 static ssize_t cmd_list_domains(struct ltt_session *session,
3081 struct lttng_domain **domains)
3082 {
3083 int ret, index = 0;
3084 ssize_t nb_dom = 0;
3085
3086 if (session->kernel_session != NULL) {
3087 DBG3("Listing domains found kernel domain");
3088 nb_dom++;
3089 }
3090
3091 if (session->ust_session != NULL) {
3092 DBG3("Listing domains found UST global domain");
3093 nb_dom++;
3094 }
3095
3096 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3097 if (*domains == NULL) {
3098 ret = -LTTCOMM_FATAL;
3099 goto error;
3100 }
3101
3102 if (session->kernel_session != NULL) {
3103 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3104 index++;
3105 }
3106
3107 if (session->ust_session != NULL) {
3108 (*domains)[index].type = LTTNG_DOMAIN_UST;
3109 index++;
3110 }
3111
3112 return nb_dom;
3113
3114 error:
3115 return ret;
3116 }
3117
3118 /*
3119 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3120 */
3121 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3122 struct lttng_channel **channels)
3123 {
3124 int ret;
3125 ssize_t nb_chan = 0;
3126
3127 switch (domain) {
3128 case LTTNG_DOMAIN_KERNEL:
3129 if (session->kernel_session != NULL) {
3130 nb_chan = session->kernel_session->channel_count;
3131 }
3132 DBG3("Number of kernel channels %zd", nb_chan);
3133 break;
3134 case LTTNG_DOMAIN_UST:
3135 if (session->ust_session != NULL) {
3136 nb_chan = lttng_ht_get_count(
3137 session->ust_session->domain_global.channels);
3138 }
3139 DBG3("Number of UST global channels %zd", nb_chan);
3140 break;
3141 default:
3142 *channels = NULL;
3143 ret = -LTTCOMM_NOT_IMPLEMENTED;
3144 goto error;
3145 }
3146
3147 if (nb_chan > 0) {
3148 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3149 if (*channels == NULL) {
3150 ret = -LTTCOMM_FATAL;
3151 goto error;
3152 }
3153
3154 list_lttng_channels(domain, session, *channels);
3155 } else {
3156 *channels = NULL;
3157 }
3158
3159 return nb_chan;
3160
3161 error:
3162 return ret;
3163 }
3164
3165 /*
3166 * Command LTTNG_LIST_EVENTS processed by the client thread.
3167 */
3168 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3169 char *channel_name, struct lttng_event **events)
3170 {
3171 int ret = 0;
3172 ssize_t nb_event = 0;
3173
3174 switch (domain) {
3175 case LTTNG_DOMAIN_KERNEL:
3176 if (session->kernel_session != NULL) {
3177 nb_event = list_lttng_kernel_events(channel_name,
3178 session->kernel_session, events);
3179 }
3180 break;
3181 case LTTNG_DOMAIN_UST:
3182 {
3183 if (session->ust_session != NULL) {
3184 nb_event = list_lttng_ust_global_events(channel_name,
3185 &session->ust_session->domain_global, events);
3186 }
3187 break;
3188 }
3189 default:
3190 ret = -LTTCOMM_NOT_IMPLEMENTED;
3191 goto error;
3192 }
3193
3194 ret = nb_event;
3195
3196 error:
3197 return ret;
3198 }
3199
3200 /*
3201 * Process the command requested by the lttng client within the command
3202 * context structure. This function make sure that the return structure (llm)
3203 * is set and ready for transmission before returning.
3204 *
3205 * Return any error encountered or 0 for success.
3206 */
3207 static int process_client_msg(struct command_ctx *cmd_ctx)
3208 {
3209 int ret = LTTCOMM_OK;
3210 int need_tracing_session = 1;
3211
3212 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3213
3214 if (opt_no_kernel && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
3215 ret = LTTCOMM_KERN_NA;
3216 goto error;
3217 }
3218
3219 /*
3220 * Check for command that don't needs to allocate a returned payload. We do
3221 * this here so we don't have to make the call for no payload at each
3222 * command.
3223 */
3224 switch(cmd_ctx->lsm->cmd_type) {
3225 case LTTNG_LIST_SESSIONS:
3226 case LTTNG_LIST_TRACEPOINTS:
3227 case LTTNG_LIST_DOMAINS:
3228 case LTTNG_LIST_CHANNELS:
3229 case LTTNG_LIST_EVENTS:
3230 break;
3231 default:
3232 /* Setup lttng message with no payload */
3233 ret = setup_lttng_msg(cmd_ctx, 0);
3234 if (ret < 0) {
3235 /* This label does not try to unlock the session */
3236 goto init_setup_error;
3237 }
3238 }
3239
3240 /* Commands that DO NOT need a session. */
3241 switch (cmd_ctx->lsm->cmd_type) {
3242 case LTTNG_CALIBRATE:
3243 case LTTNG_CREATE_SESSION:
3244 case LTTNG_LIST_SESSIONS:
3245 case LTTNG_LIST_TRACEPOINTS:
3246 need_tracing_session = 0;
3247 break;
3248 default:
3249 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3250 session_lock_list();
3251 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3252 session_unlock_list();
3253 if (cmd_ctx->session == NULL) {
3254 if (cmd_ctx->lsm->session.name != NULL) {
3255 ret = LTTCOMM_SESS_NOT_FOUND;
3256 } else {
3257 /* If no session name specified */
3258 ret = LTTCOMM_SELECT_SESS;
3259 }
3260 goto error;
3261 } else {
3262 /* Acquire lock for the session */
3263 session_lock(cmd_ctx->session);
3264 }
3265 break;
3266 }
3267
3268 /*
3269 * Check domain type for specific "pre-action".
3270 */
3271 switch (cmd_ctx->lsm->domain.type) {
3272 case LTTNG_DOMAIN_KERNEL:
3273 if (!is_root) {
3274 ret = LTTCOMM_KERN_NA;
3275 goto error;
3276 }
3277
3278 /* Kernel tracer check */
3279 if (kernel_tracer_fd == 0) {
3280 /* Basically, load kernel tracer modules */
3281 init_kernel_tracer();
3282 if (kernel_tracer_fd == 0) {
3283 ret = LTTCOMM_KERN_NA;
3284 goto error;
3285 }
3286 }
3287
3288 /* Need a session for kernel command */
3289 if (need_tracing_session) {
3290 if (cmd_ctx->session->kernel_session == NULL) {
3291 ret = create_kernel_session(cmd_ctx->session);
3292 if (ret < 0) {
3293 ret = LTTCOMM_KERN_SESS_FAIL;
3294 goto error;
3295 }
3296 }
3297
3298 /* Start the kernel consumer daemon */
3299 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3300 if (kconsumer_data.pid == 0 &&
3301 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3302 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3303 ret = start_consumerd(&kconsumer_data);
3304 if (ret < 0) {
3305 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3306 goto error;
3307 }
3308 } else {
3309 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3310 }
3311 }
3312 break;
3313 case LTTNG_DOMAIN_UST:
3314 {
3315 if (need_tracing_session) {
3316 if (cmd_ctx->session->ust_session == NULL) {
3317 ret = create_ust_session(cmd_ctx->session,
3318 &cmd_ctx->lsm->domain);
3319 if (ret != LTTCOMM_OK) {
3320 goto error;
3321 }
3322 }
3323 /* Start the UST consumer daemons */
3324 /* 64-bit */
3325 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3326 if (consumerd64_bin[0] != '\0' &&
3327 ustconsumer64_data.pid == 0 &&
3328 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3329 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3330 ret = start_consumerd(&ustconsumer64_data);
3331 if (ret < 0) {
3332 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3333 ust_consumerd64_fd = -EINVAL;
3334 goto error;
3335 }
3336
3337 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3338 } else {
3339 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3340 }
3341 /* 32-bit */
3342 if (consumerd32_bin[0] != '\0' &&
3343 ustconsumer32_data.pid == 0 &&
3344 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3345 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3346 ret = start_consumerd(&ustconsumer32_data);
3347 if (ret < 0) {
3348 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3349 ust_consumerd32_fd = -EINVAL;
3350 goto error;
3351 }
3352 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3353 } else {
3354 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3355 }
3356 }
3357 break;
3358 }
3359 default:
3360 break;
3361 }
3362
3363 /*
3364 * Check that the UID or GID match that of the tracing session.
3365 * The root user can interact with all sessions.
3366 */
3367 if (need_tracing_session) {
3368 if (!session_access_ok(cmd_ctx->session,
3369 cmd_ctx->creds.uid, cmd_ctx->creds.gid)) {
3370 ret = LTTCOMM_EPERM;
3371 goto error;
3372 }
3373 }
3374
3375 /* Process by command type */
3376 switch (cmd_ctx->lsm->cmd_type) {
3377 case LTTNG_ADD_CONTEXT:
3378 {
3379 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3380 cmd_ctx->lsm->u.context.channel_name,
3381 cmd_ctx->lsm->u.context.event_name,
3382 &cmd_ctx->lsm->u.context.ctx);
3383 break;
3384 }
3385 case LTTNG_DISABLE_CHANNEL:
3386 {
3387 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3388 cmd_ctx->lsm->u.disable.channel_name);
3389 break;
3390 }
3391 case LTTNG_DISABLE_EVENT:
3392 {
3393 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3394 cmd_ctx->lsm->u.disable.channel_name,
3395 cmd_ctx->lsm->u.disable.name);
3396 ret = LTTCOMM_OK;
3397 break;
3398 }
3399 case LTTNG_DISABLE_ALL_EVENT:
3400 {
3401 DBG("Disabling all events");
3402
3403 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3404 cmd_ctx->lsm->u.disable.channel_name);
3405 break;
3406 }
3407 case LTTNG_ENABLE_CHANNEL:
3408 {
3409 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3410 &cmd_ctx->lsm->u.channel.chan);
3411 break;
3412 }
3413 case LTTNG_ENABLE_EVENT:
3414 {
3415 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3416 cmd_ctx->lsm->u.enable.channel_name,
3417 &cmd_ctx->lsm->u.enable.event);
3418 break;
3419 }
3420 case LTTNG_ENABLE_ALL_EVENT:
3421 {
3422 DBG("Enabling all events");
3423
3424 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3425 cmd_ctx->lsm->u.enable.channel_name,
3426 cmd_ctx->lsm->u.enable.event.type);
3427 break;
3428 }
3429 case LTTNG_LIST_TRACEPOINTS:
3430 {
3431 struct lttng_event *events;
3432 ssize_t nb_events;
3433
3434 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3435 if (nb_events < 0) {
3436 ret = -nb_events;
3437 goto error;
3438 }
3439
3440 /*
3441 * Setup lttng message with payload size set to the event list size in
3442 * bytes and then copy list into the llm payload.
3443 */
3444 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3445 if (ret < 0) {
3446 free(events);
3447 goto setup_error;
3448 }
3449
3450 /* Copy event list into message payload */
3451 memcpy(cmd_ctx->llm->payload, events,
3452 sizeof(struct lttng_event) * nb_events);
3453
3454 free(events);
3455
3456 ret = LTTCOMM_OK;
3457 break;
3458 }
3459 case LTTNG_START_TRACE:
3460 {
3461 ret = cmd_start_trace(cmd_ctx->session);
3462 break;
3463 }
3464 case LTTNG_STOP_TRACE:
3465 {
3466 ret = cmd_stop_trace(cmd_ctx->session);
3467 break;
3468 }
3469 case LTTNG_CREATE_SESSION:
3470 {
3471 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3472 cmd_ctx->lsm->session.path, &cmd_ctx->creds);
3473 break;
3474 }
3475 case LTTNG_DESTROY_SESSION:
3476 {
3477 ret = cmd_destroy_session(cmd_ctx->session,
3478 cmd_ctx->lsm->session.name);
3479 break;
3480 }
3481 case LTTNG_LIST_DOMAINS:
3482 {
3483 ssize_t nb_dom;
3484 struct lttng_domain *domains;
3485
3486 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3487 if (nb_dom < 0) {
3488 ret = -nb_dom;
3489 goto error;
3490 }
3491
3492 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3493 if (ret < 0) {
3494 goto setup_error;
3495 }
3496
3497 /* Copy event list into message payload */
3498 memcpy(cmd_ctx->llm->payload, domains,
3499 nb_dom * sizeof(struct lttng_domain));
3500
3501 free(domains);
3502
3503 ret = LTTCOMM_OK;
3504 break;
3505 }
3506 case LTTNG_LIST_CHANNELS:
3507 {
3508 size_t nb_chan;
3509 struct lttng_channel *channels;
3510
3511 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
3512 cmd_ctx->session, &channels);
3513 if (nb_chan < 0) {
3514 ret = -nb_chan;
3515 goto error;
3516 }
3517
3518 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3519 if (ret < 0) {
3520 goto setup_error;
3521 }
3522
3523 /* Copy event list into message payload */
3524 memcpy(cmd_ctx->llm->payload, channels,
3525 nb_chan * sizeof(struct lttng_channel));
3526
3527 free(channels);
3528
3529 ret = LTTCOMM_OK;
3530 break;
3531 }
3532 case LTTNG_LIST_EVENTS:
3533 {
3534 ssize_t nb_event;
3535 struct lttng_event *events = NULL;
3536
3537 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
3538 cmd_ctx->lsm->u.list.channel_name, &events);
3539 if (nb_event < 0) {
3540 ret = -nb_event;
3541 goto error;
3542 }
3543
3544 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3545 if (ret < 0) {
3546 goto setup_error;
3547 }
3548
3549 /* Copy event list into message payload */
3550 memcpy(cmd_ctx->llm->payload, events,
3551 nb_event * sizeof(struct lttng_event));
3552
3553 free(events);
3554
3555 ret = LTTCOMM_OK;
3556 break;
3557 }
3558 case LTTNG_LIST_SESSIONS:
3559 {
3560 unsigned int nr_sessions;
3561
3562 session_lock_list();
3563 nr_sessions = lttng_sessions_count(cmd_ctx->creds.uid, cmd_ctx->creds.gid);
3564 if (nr_sessions == 0) {
3565 ret = LTTCOMM_NO_SESSION;
3566 session_unlock_list();
3567 goto error;
3568 }
3569 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * nr_sessions);
3570 if (ret < 0) {
3571 session_unlock_list();
3572 goto setup_error;
3573 }
3574
3575 /* Filled the session array */
3576 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload),
3577 cmd_ctx->creds.uid, cmd_ctx->creds.gid);
3578
3579 session_unlock_list();
3580
3581 ret = LTTCOMM_OK;
3582 break;
3583 }
3584 case LTTNG_CALIBRATE:
3585 {
3586 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3587 &cmd_ctx->lsm->u.calibrate);
3588 break;
3589 }
3590 case LTTNG_REGISTER_CONSUMER:
3591 {
3592 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3593 cmd_ctx->lsm->u.reg.path);
3594 break;
3595 }
3596 default:
3597 ret = LTTCOMM_UND;
3598 break;
3599 }
3600
3601 error:
3602 if (cmd_ctx->llm == NULL) {
3603 DBG("Missing llm structure. Allocating one.");
3604 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3605 goto setup_error;
3606 }
3607 }
3608 /* Set return code */
3609 cmd_ctx->llm->ret_code = ret;
3610 setup_error:
3611 if (cmd_ctx->session) {
3612 session_unlock(cmd_ctx->session);
3613 }
3614 init_setup_error:
3615 return ret;
3616 }
3617
3618 /*
3619 * This thread manage all clients request using the unix client socket for
3620 * communication.
3621 */
3622 static void *thread_manage_clients(void *data)
3623 {
3624 int sock = 0, ret, i, pollfd;
3625 uint32_t revents, nb_fd;
3626 struct command_ctx *cmd_ctx = NULL;
3627 struct lttng_poll_event events;
3628
3629 DBG("[thread] Manage client started");
3630
3631 rcu_register_thread();
3632
3633 ret = lttcomm_listen_unix_sock(client_sock);
3634 if (ret < 0) {
3635 goto error;
3636 }
3637
3638 /*
3639 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3640 * more will be added to this poll set.
3641 */
3642 ret = create_thread_poll_set(&events, 2);
3643 if (ret < 0) {
3644 goto error;
3645 }
3646
3647 /* Add the application registration socket */
3648 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3649 if (ret < 0) {
3650 goto error;
3651 }
3652
3653 /*
3654 * Notify parent pid that we are ready to accept command for client side.
3655 */
3656 if (opt_sig_parent) {
3657 kill(ppid, SIGCHLD);
3658 }
3659
3660 while (1) {
3661 DBG("Accepting client command ...");
3662
3663 nb_fd = LTTNG_POLL_GETNB(&events);
3664
3665 /* Inifinite blocking call, waiting for transmission */
3666 ret = lttng_poll_wait(&events, -1);
3667 if (ret < 0) {
3668 goto error;
3669 }
3670
3671 for (i = 0; i < nb_fd; i++) {
3672 /* Fetch once the poll data */
3673 revents = LTTNG_POLL_GETEV(&events, i);
3674 pollfd = LTTNG_POLL_GETFD(&events, i);
3675
3676 /* Thread quit pipe has been closed. Killing thread. */
3677 ret = check_thread_quit_pipe(pollfd, revents);
3678 if (ret) {
3679 goto error;
3680 }
3681
3682 /* Event on the registration socket */
3683 if (pollfd == client_sock) {
3684 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3685 ERR("Client socket poll error");
3686 goto error;
3687 }
3688 }
3689 }
3690
3691 DBG("Wait for client response");
3692
3693 sock = lttcomm_accept_unix_sock(client_sock);
3694 if (sock < 0) {
3695 goto error;
3696 }
3697
3698 /* Set socket option for credentials retrieval */
3699 ret = lttcomm_setsockopt_creds_unix_sock(sock);
3700 if (ret < 0) {
3701 goto error;
3702 }
3703
3704 /* Allocate context command to process the client request */
3705 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3706 if (cmd_ctx == NULL) {
3707 perror("zmalloc cmd_ctx");
3708 goto error;
3709 }
3710
3711 /* Allocate data buffer for reception */
3712 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3713 if (cmd_ctx->lsm == NULL) {
3714 perror("zmalloc cmd_ctx->lsm");
3715 goto error;
3716 }
3717
3718 cmd_ctx->llm = NULL;
3719 cmd_ctx->session = NULL;
3720
3721 /*
3722 * Data is received from the lttng client. The struct
3723 * lttcomm_session_msg (lsm) contains the command and data request of
3724 * the client.
3725 */
3726 DBG("Receiving data from client ...");
3727 ret = lttcomm_recv_creds_unix_sock(sock, cmd_ctx->lsm,
3728 sizeof(struct lttcomm_session_msg), &cmd_ctx->creds);
3729 if (ret <= 0) {
3730 DBG("Nothing recv() from client... continuing");
3731 close(sock);
3732 free(cmd_ctx);
3733 continue;
3734 }
3735
3736 // TODO: Validate cmd_ctx including sanity check for
3737 // security purpose.
3738
3739 rcu_thread_online();
3740 /*
3741 * This function dispatch the work to the kernel or userspace tracer
3742 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3743 * informations for the client. The command context struct contains
3744 * everything this function may needs.
3745 */
3746 ret = process_client_msg(cmd_ctx);
3747 rcu_thread_offline();
3748 if (ret < 0) {
3749 /*
3750 * TODO: Inform client somehow of the fatal error. At
3751 * this point, ret < 0 means that a zmalloc failed
3752 * (ENOMEM). Error detected but still accept command.
3753 */
3754 clean_command_ctx(&cmd_ctx);
3755 continue;
3756 }
3757
3758 DBG("Sending response (size: %d, retcode: %s)",
3759 cmd_ctx->lttng_msg_size,
3760 lttng_strerror(-cmd_ctx->llm->ret_code));
3761 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3762 if (ret < 0) {
3763 ERR("Failed to send data back to client");
3764 }
3765
3766 /* End of transmission */
3767 close(sock);
3768
3769 clean_command_ctx(&cmd_ctx);
3770 }
3771
3772 error:
3773 DBG("Client thread dying");
3774 unlink(client_unix_sock_path);
3775 close(client_sock);
3776 close(sock);
3777
3778 lttng_poll_clean(&events);
3779 clean_command_ctx(&cmd_ctx);
3780
3781 rcu_unregister_thread();
3782 return NULL;
3783 }
3784
3785
3786 /*
3787 * usage function on stderr
3788 */
3789 static void usage(void)
3790 {
3791 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3792 fprintf(stderr, " -h, --help Display this usage.\n");
3793 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3794 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3795 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3796 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3797 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
3798 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
3799 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
3800 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
3801 fprintf(stderr, " --consumerd32-path PATH Specify path for the 32-bit UST consumer daemon binary\n");
3802 fprintf(stderr, " --consumerd32-libdir PATH Specify path for the 32-bit UST consumer daemon libraries\n");
3803 fprintf(stderr, " --consumerd64-path PATH Specify path for the 64-bit UST consumer daemon binary\n");
3804 fprintf(stderr, " --consumerd64-libdir PATH Specify path for the 64-bit UST consumer daemon libraries\n");
3805 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3806 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3807 fprintf(stderr, " -V, --version Show version number.\n");
3808 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3809 fprintf(stderr, " -q, --quiet No output at all.\n");
3810 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3811 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3812 fprintf(stderr, " --no-kernel Disable kernel tracer\n");
3813 }
3814
3815 /*
3816 * daemon argument parsing
3817 */
3818 static int parse_args(int argc, char **argv)
3819 {
3820 int c;
3821
3822 static struct option long_options[] = {
3823 { "client-sock", 1, 0, 'c' },
3824 { "apps-sock", 1, 0, 'a' },
3825 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3826 { "kconsumerd-err-sock", 1, 0, 'E' },
3827 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
3828 { "ustconsumerd32-err-sock", 1, 0, 'H' },
3829 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
3830 { "ustconsumerd64-err-sock", 1, 0, 'F' },
3831 { "consumerd32-path", 1, 0, 'u' },
3832 { "consumerd32-libdir", 1, 0, 'U' },
3833 { "consumerd64-path", 1, 0, 't' },
3834 { "consumerd64-libdir", 1, 0, 'T' },
3835 { "daemonize", 0, 0, 'd' },
3836 { "sig-parent", 0, 0, 'S' },
3837 { "help", 0, 0, 'h' },
3838 { "group", 1, 0, 'g' },
3839 { "version", 0, 0, 'V' },
3840 { "quiet", 0, 0, 'q' },
3841 { "verbose", 0, 0, 'v' },
3842 { "verbose-consumer", 0, 0, 'Z' },
3843 { "no-kernel", 0, 0, 'N' },
3844 { NULL, 0, 0, 0 }
3845 };
3846
3847 while (1) {
3848 int option_index = 0;
3849 c = getopt_long(argc, argv, "dhqvVSN" "a:c:g:s:C:E:D:F:Z:u:t",
3850 long_options, &option_index);
3851 if (c == -1) {
3852 break;
3853 }
3854
3855 switch (c) {
3856 case 0:
3857 fprintf(stderr, "option %s", long_options[option_index].name);
3858 if (optarg) {
3859 fprintf(stderr, " with arg %s\n", optarg);
3860 }
3861 break;
3862 case 'c':
3863 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3864 break;
3865 case 'a':
3866 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3867 break;
3868 case 'd':
3869 opt_daemon = 1;
3870 break;
3871 case 'g':
3872 opt_tracing_group = optarg;
3873 break;
3874 case 'h':
3875 usage();
3876 exit(EXIT_FAILURE);
3877 case 'V':
3878 fprintf(stdout, "%s\n", VERSION);
3879 exit(EXIT_SUCCESS);
3880 case 'S':
3881 opt_sig_parent = 1;
3882 break;
3883 case 'E':
3884 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3885 break;
3886 case 'C':
3887 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3888 break;
3889 case 'F':
3890 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3891 break;
3892 case 'D':
3893 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3894 break;
3895 case 'H':
3896 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3897 break;
3898 case 'G':
3899 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3900 break;
3901 case 'N':
3902 opt_no_kernel = 1;
3903 break;
3904 case 'q':
3905 opt_quiet = 1;
3906 break;
3907 case 'v':
3908 /* Verbose level can increase using multiple -v */
3909 opt_verbose += 1;
3910 break;
3911 case 'Z':
3912 opt_verbose_consumer += 1;
3913 break;
3914 case 'u':
3915 consumerd32_bin= optarg;
3916 break;
3917 case 'U':
3918 consumerd32_libdir = optarg;
3919 break;
3920 case 't':
3921 consumerd64_bin = optarg;
3922 break;
3923 case 'T':
3924 consumerd64_libdir = optarg;
3925 break;
3926 default:
3927 /* Unknown option or other error.
3928 * Error is printed by getopt, just return */
3929 return -1;
3930 }
3931 }
3932
3933 return 0;
3934 }
3935
3936 /*
3937 * Creates the two needed socket by the daemon.
3938 * apps_sock - The communication socket for all UST apps.
3939 * client_sock - The communication of the cli tool (lttng).
3940 */
3941 static int init_daemon_socket(void)
3942 {
3943 int ret = 0;
3944 mode_t old_umask;
3945
3946 old_umask = umask(0);
3947
3948 /* Create client tool unix socket */
3949 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3950 if (client_sock < 0) {
3951 ERR("Create unix sock failed: %s", client_unix_sock_path);
3952 ret = -1;
3953 goto end;
3954 }
3955
3956 /* File permission MUST be 660 */
3957 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3958 if (ret < 0) {
3959 ERR("Set file permissions failed: %s", client_unix_sock_path);
3960 perror("chmod");
3961 goto end;
3962 }
3963
3964 /* Create the application unix socket */
3965 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3966 if (apps_sock < 0) {
3967 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3968 ret = -1;
3969 goto end;
3970 }
3971
3972 /* File permission MUST be 666 */
3973 ret = chmod(apps_unix_sock_path,
3974 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3975 if (ret < 0) {
3976 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3977 perror("chmod");
3978 goto end;
3979 }
3980
3981 end:
3982 umask(old_umask);
3983 return ret;
3984 }
3985
3986 /*
3987 * Check if the global socket is available, and if a daemon is answering at the
3988 * other side. If yes, error is returned.
3989 */
3990 static int check_existing_daemon(void)
3991 {
3992 if (access(client_unix_sock_path, F_OK) < 0 &&
3993 access(apps_unix_sock_path, F_OK) < 0) {
3994 return 0;
3995 }
3996
3997 /* Is there anybody out there ? */
3998 if (lttng_session_daemon_alive()) {
3999 return -EEXIST;
4000 } else {
4001 return 0;
4002 }
4003 }
4004
4005 /*
4006 * Set the tracing group gid onto the client socket.
4007 *
4008 * Race window between mkdir and chown is OK because we are going from more
4009 * permissive (root.root) to les permissive (root.tracing).
4010 */
4011 static int set_permissions(char *rundir)
4012 {
4013 int ret;
4014 gid_t gid;
4015
4016 gid = allowed_group();
4017 if (gid < 0) {
4018 WARN("No tracing group detected");
4019 ret = 0;
4020 goto end;
4021 }
4022
4023 /* Set lttng run dir */
4024 ret = chown(rundir, 0, gid);
4025 if (ret < 0) {
4026 ERR("Unable to set group on %s", rundir);
4027 perror("chown");
4028 }
4029
4030 /* lttng client socket path */
4031 ret = chown(client_unix_sock_path, 0, gid);
4032 if (ret < 0) {
4033 ERR("Unable to set group on %s", client_unix_sock_path);
4034 perror("chown");
4035 }
4036
4037 /* kconsumer error socket path */
4038 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
4039 if (ret < 0) {
4040 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
4041 perror("chown");
4042 }
4043
4044 /* 64-bit ustconsumer error socket path */
4045 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
4046 if (ret < 0) {
4047 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
4048 perror("chown");
4049 }
4050
4051 /* 32-bit ustconsumer compat32 error socket path */
4052 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
4053 if (ret < 0) {
4054 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
4055 perror("chown");
4056 }
4057
4058 DBG("All permissions are set");
4059
4060 end:
4061 return ret;
4062 }
4063
4064 /*
4065 * Create the pipe used to wake up the kernel thread.
4066 */
4067 static int create_kernel_poll_pipe(void)
4068 {
4069 return pipe2(kernel_poll_pipe, O_CLOEXEC);
4070 }
4071
4072 /*
4073 * Create the application command pipe to wake thread_manage_apps.
4074 */
4075 static int create_apps_cmd_pipe(void)
4076 {
4077 return pipe2(apps_cmd_pipe, O_CLOEXEC);
4078 }
4079
4080 /*
4081 * Create the lttng run directory needed for all global sockets and pipe.
4082 */
4083 static int create_lttng_rundir(const char *rundir)
4084 {
4085 int ret;
4086
4087 DBG3("Creating LTTng run directory: %s", rundir);
4088
4089 ret = mkdir(rundir, S_IRWXU | S_IRWXG );
4090 if (ret < 0) {
4091 if (errno != EEXIST) {
4092 ERR("Unable to create %s", rundir);
4093 goto error;
4094 } else {
4095 ret = 0;
4096 }
4097 }
4098
4099 error:
4100 return ret;
4101 }
4102
4103 /*
4104 * Setup sockets and directory needed by the kconsumerd communication with the
4105 * session daemon.
4106 */
4107 static int set_consumer_sockets(struct consumer_data *consumer_data,
4108 const char *rundir)
4109 {
4110 int ret;
4111 char path[PATH_MAX];
4112
4113 switch (consumer_data->type) {
4114 case LTTNG_CONSUMER_KERNEL:
4115 snprintf(path, PATH_MAX, KCONSUMERD_PATH, rundir);
4116 break;
4117 case LTTNG_CONSUMER64_UST:
4118 snprintf(path, PATH_MAX, USTCONSUMERD64_PATH, rundir);
4119 break;
4120 case LTTNG_CONSUMER32_UST:
4121 snprintf(path, PATH_MAX, USTCONSUMERD32_PATH, rundir);
4122 break;
4123 default:
4124 ERR("Consumer type unknown");
4125 ret = -EINVAL;
4126 goto error;
4127 }
4128
4129 DBG2("Creating consumer directory: %s", path);
4130
4131 ret = mkdir(path, S_IRWXU | S_IRWXG);
4132 if (ret < 0) {
4133 if (errno != EEXIST) {
4134 ERR("Failed to create %s", path);
4135 goto error;
4136 }
4137 ret = 0;
4138 }
4139
4140 /* Create the kconsumerd error unix socket */
4141 consumer_data->err_sock =
4142 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
4143 if (consumer_data->err_sock < 0) {
4144 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
4145 ret = -1;
4146 goto error;
4147 }
4148
4149 /* File permission MUST be 660 */
4150 ret = chmod(consumer_data->err_unix_sock_path,
4151 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
4152 if (ret < 0) {
4153 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
4154 PERROR("chmod");
4155 goto error;
4156 }
4157
4158 error:
4159 return ret;
4160 }
4161
4162 /*
4163 * Signal handler for the daemon
4164 *
4165 * Simply stop all worker threads, leaving main() return gracefully after
4166 * joining all threads and calling cleanup().
4167 */
4168 static void sighandler(int sig)
4169 {
4170 switch (sig) {
4171 case SIGPIPE:
4172 DBG("SIGPIPE caugth");
4173 return;
4174 case SIGINT:
4175 DBG("SIGINT caugth");
4176 stop_threads();
4177 break;
4178 case SIGTERM:
4179 DBG("SIGTERM caugth");
4180 stop_threads();
4181 break;
4182 default:
4183 break;
4184 }
4185 }
4186
4187 /*
4188 * Setup signal handler for :
4189 * SIGINT, SIGTERM, SIGPIPE
4190 */
4191 static int set_signal_handler(void)
4192 {
4193 int ret = 0;
4194 struct sigaction sa;
4195 sigset_t sigset;
4196
4197 if ((ret = sigemptyset(&sigset)) < 0) {
4198 perror("sigemptyset");
4199 return ret;
4200 }
4201
4202 sa.sa_handler = sighandler;
4203 sa.sa_mask = sigset;
4204 sa.sa_flags = 0;
4205 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
4206 perror("sigaction");
4207 return ret;
4208 }
4209
4210 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
4211 perror("sigaction");
4212 return ret;
4213 }
4214
4215 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
4216 perror("sigaction");
4217 return ret;
4218 }
4219
4220 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
4221
4222 return ret;
4223 }
4224
4225 /*
4226 * Set open files limit to unlimited. This daemon can open a large number of
4227 * file descriptors in order to consumer multiple kernel traces.
4228 */
4229 static void set_ulimit(void)
4230 {
4231 int ret;
4232 struct rlimit lim;
4233
4234 /* The kernel does not allowed an infinite limit for open files */
4235 lim.rlim_cur = 65535;
4236 lim.rlim_max = 65535;
4237
4238 ret = setrlimit(RLIMIT_NOFILE, &lim);
4239 if (ret < 0) {
4240 perror("failed to set open files limit");
4241 }
4242 }
4243
4244 /*
4245 * main
4246 */
4247 int main(int argc, char **argv)
4248 {
4249 int ret = 0;
4250 void *status;
4251 const char *home_path;
4252
4253 rcu_register_thread();
4254
4255 /* Create thread quit pipe */
4256 if ((ret = init_thread_quit_pipe()) < 0) {
4257 goto error;
4258 }
4259
4260 setup_consumerd_path();
4261
4262 /* Parse arguments */
4263 progname = argv[0];
4264 if ((ret = parse_args(argc, argv) < 0)) {
4265 goto error;
4266 }
4267
4268 /* Daemonize */
4269 if (opt_daemon) {
4270 ret = daemon(0, 0);
4271 if (ret < 0) {
4272 perror("daemon");
4273 goto error;
4274 }
4275 }
4276
4277 /* Check if daemon is UID = 0 */
4278 is_root = !getuid();
4279
4280 if (is_root) {
4281 rundir = strdup(LTTNG_RUNDIR);
4282
4283 /* Create global run dir with root access */
4284 ret = create_lttng_rundir(rundir);
4285 if (ret < 0) {
4286 goto error;
4287 }
4288
4289 if (strlen(apps_unix_sock_path) == 0) {
4290 snprintf(apps_unix_sock_path, PATH_MAX,
4291 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
4292 }
4293
4294 if (strlen(client_unix_sock_path) == 0) {
4295 snprintf(client_unix_sock_path, PATH_MAX,
4296 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
4297 }
4298
4299 /* Set global SHM for ust */
4300 if (strlen(wait_shm_path) == 0) {
4301 snprintf(wait_shm_path, PATH_MAX,
4302 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
4303 }
4304
4305 /* Setup kernel consumerd path */
4306 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX,
4307 KCONSUMERD_ERR_SOCK_PATH, rundir);
4308 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX,
4309 KCONSUMERD_CMD_SOCK_PATH, rundir);
4310
4311 DBG2("Kernel consumer err path: %s",
4312 kconsumer_data.err_unix_sock_path);
4313 DBG2("Kernel consumer cmd path: %s",
4314 kconsumer_data.cmd_unix_sock_path);
4315 } else {
4316 home_path = get_home_dir();
4317 if (home_path == NULL) {
4318 /* TODO: Add --socket PATH option */
4319 ERR("Can't get HOME directory for sockets creation.");
4320 ret = -EPERM;
4321 goto error;
4322 }
4323
4324 /*
4325 * Create rundir from home path. This will create something like
4326 * $HOME/.lttng
4327 */
4328 ret = asprintf(&rundir, LTTNG_HOME_RUNDIR, home_path);
4329 if (ret < 0) {
4330 ret = -ENOMEM;
4331 goto error;
4332 }
4333
4334 ret = create_lttng_rundir(rundir);
4335 if (ret < 0) {
4336 goto error;
4337 }
4338
4339 if (strlen(apps_unix_sock_path) == 0) {
4340 snprintf(apps_unix_sock_path, PATH_MAX,
4341 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
4342 }
4343
4344 /* Set the cli tool unix socket path */
4345 if (strlen(client_unix_sock_path) == 0) {
4346 snprintf(client_unix_sock_path, PATH_MAX,
4347 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
4348 }
4349
4350 /* Set global SHM for ust */
4351 if (strlen(wait_shm_path) == 0) {
4352 snprintf(wait_shm_path, PATH_MAX,
4353 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
4354 }
4355 }
4356
4357 DBG("Client socket path %s", client_unix_sock_path);
4358 DBG("Application socket path %s", apps_unix_sock_path);
4359 DBG("LTTng run directory path: %s", rundir);
4360
4361 /* 32 bits consumerd path setup */
4362 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX,
4363 USTCONSUMERD32_ERR_SOCK_PATH, rundir);
4364 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX,
4365 USTCONSUMERD32_CMD_SOCK_PATH, rundir);
4366
4367 DBG2("UST consumer 32 bits err path: %s",
4368 ustconsumer32_data.err_unix_sock_path);
4369 DBG2("UST consumer 32 bits cmd path: %s",
4370 ustconsumer32_data.cmd_unix_sock_path);
4371
4372 /* 64 bits consumerd path setup */
4373 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX,
4374 USTCONSUMERD64_ERR_SOCK_PATH, rundir);
4375 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX,
4376 USTCONSUMERD64_CMD_SOCK_PATH, rundir);
4377
4378 DBG2("UST consumer 64 bits err path: %s",
4379 ustconsumer64_data.err_unix_sock_path);
4380 DBG2("UST consumer 64 bits cmd path: %s",
4381 ustconsumer64_data.cmd_unix_sock_path);
4382
4383 /*
4384 * See if daemon already exist.
4385 */
4386 if ((ret = check_existing_daemon()) < 0) {
4387 ERR("Already running daemon.\n");
4388 /*
4389 * We do not goto exit because we must not cleanup()
4390 * because a daemon is already running.
4391 */
4392 goto error;
4393 }
4394
4395 /* After this point, we can safely call cleanup() with "goto exit" */
4396
4397 /*
4398 * These actions must be executed as root. We do that *after* setting up
4399 * the sockets path because we MUST make the check for another daemon using
4400 * those paths *before* trying to set the kernel consumer sockets and init
4401 * kernel tracer.
4402 */
4403 if (is_root) {
4404 ret = set_consumer_sockets(&kconsumer_data, rundir);
4405 if (ret < 0) {
4406 goto exit;
4407 }
4408
4409 /* Setup kernel tracer */
4410 if (!opt_no_kernel) {
4411 init_kernel_tracer();
4412 }
4413
4414 /* Set ulimit for open files */
4415 set_ulimit();
4416 }
4417
4418 ret = set_consumer_sockets(&ustconsumer64_data, rundir);
4419 if (ret < 0) {
4420 goto exit;
4421 }
4422
4423 ret = set_consumer_sockets(&ustconsumer32_data, rundir);
4424 if (ret < 0) {
4425 goto exit;
4426 }
4427
4428 if ((ret = set_signal_handler()) < 0) {
4429 goto exit;
4430 }
4431
4432 /* Setup the needed unix socket */
4433 if ((ret = init_daemon_socket()) < 0) {
4434 goto exit;
4435 }
4436
4437 /* Set credentials to socket */
4438 if (is_root && ((ret = set_permissions(rundir)) < 0)) {
4439 goto exit;
4440 }
4441
4442 /* Get parent pid if -S, --sig-parent is specified. */
4443 if (opt_sig_parent) {
4444 ppid = getppid();
4445 }
4446
4447 /* Setup the kernel pipe for waking up the kernel thread */
4448 if ((ret = create_kernel_poll_pipe()) < 0) {
4449 goto exit;
4450 }
4451
4452 /* Setup the thread apps communication pipe. */
4453 if ((ret = create_apps_cmd_pipe()) < 0) {
4454 goto exit;
4455 }
4456
4457 /* Init UST command queue. */
4458 cds_wfq_init(&ust_cmd_queue.queue);
4459
4460 /* Init UST app hash table */
4461 ust_app_ht_alloc();
4462
4463 /*
4464 * Get session list pointer. This pointer MUST NOT be free(). This list is
4465 * statically declared in session.c
4466 */
4467 session_list_ptr = session_get_list();
4468
4469 /* Set up max poll set size */
4470 lttng_poll_set_max_size();
4471
4472 /* Create thread to manage the client socket */
4473 ret = pthread_create(&client_thread, NULL,
4474 thread_manage_clients, (void *) NULL);
4475 if (ret != 0) {
4476 perror("pthread_create clients");
4477 goto exit_client;
4478 }
4479
4480 /* Create thread to dispatch registration */
4481 ret = pthread_create(&dispatch_thread, NULL,
4482 thread_dispatch_ust_registration, (void *) NULL);
4483 if (ret != 0) {
4484 perror("pthread_create dispatch");
4485 goto exit_dispatch;
4486 }
4487
4488 /* Create thread to manage application registration. */
4489 ret = pthread_create(&reg_apps_thread, NULL,
4490 thread_registration_apps, (void *) NULL);
4491 if (ret != 0) {
4492 perror("pthread_create registration");
4493 goto exit_reg_apps;
4494 }
4495
4496 /* Create thread to manage application socket */
4497 ret = pthread_create(&apps_thread, NULL,
4498 thread_manage_apps, (void *) NULL);
4499 if (ret != 0) {
4500 perror("pthread_create apps");
4501 goto exit_apps;
4502 }
4503
4504 /* Create kernel thread to manage kernel event */
4505 ret = pthread_create(&kernel_thread, NULL,
4506 thread_manage_kernel, (void *) NULL);
4507 if (ret != 0) {
4508 perror("pthread_create kernel");
4509 goto exit_kernel;
4510 }
4511
4512 ret = pthread_join(kernel_thread, &status);
4513 if (ret != 0) {
4514 perror("pthread_join");
4515 goto error; /* join error, exit without cleanup */
4516 }
4517
4518 exit_kernel:
4519 ret = pthread_join(apps_thread, &status);
4520 if (ret != 0) {
4521 perror("pthread_join");
4522 goto error; /* join error, exit without cleanup */
4523 }
4524
4525 exit_apps:
4526 ret = pthread_join(reg_apps_thread, &status);
4527 if (ret != 0) {
4528 perror("pthread_join");
4529 goto error; /* join error, exit without cleanup */
4530 }
4531
4532 exit_reg_apps:
4533 ret = pthread_join(dispatch_thread, &status);
4534 if (ret != 0) {
4535 perror("pthread_join");
4536 goto error; /* join error, exit without cleanup */
4537 }
4538
4539 exit_dispatch:
4540 ret = pthread_join(client_thread, &status);
4541 if (ret != 0) {
4542 perror("pthread_join");
4543 goto error; /* join error, exit without cleanup */
4544 }
4545
4546 ret = join_consumer_thread(&kconsumer_data);
4547 if (ret != 0) {
4548 perror("join_consumer");
4549 goto error; /* join error, exit without cleanup */
4550 }
4551
4552 exit_client:
4553 exit:
4554 /*
4555 * cleanup() is called when no other thread is running.
4556 */
4557 rcu_thread_online();
4558 cleanup();
4559 rcu_thread_offline();
4560 rcu_unregister_thread();
4561 if (!ret) {
4562 exit(EXIT_SUCCESS);
4563 }
4564 error:
4565 exit(EXIT_FAILURE);
4566 }
LTTng 2.0 tools and control repository
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