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Don't init kernel tracer if not root (UID=0)
[lttng-tools.git] / 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 <lttng-consumerd.h>
42 #include <lttng-ht.h>
43 #include <lttng-sessiond-comm.h>
44 #include <lttng/lttng-consumer.h>
45
46 #include <lttngerr.h>
47 #include "common/runas.h"
48
49 #include "channel.h"
50 #include "compat/poll.h"
51 #include "context.h"
52 #include "event.h"
53 #include "futex.h"
54 #include "kernel.h"
55 #include "lttng-sessiond.h"
56 #include "shm.h"
57 #include "ust-app.h"
58 #include "ust-ctl.h"
59 #include "utils.h"
60
61 #define CONSUMERD_FILE "lttng-consumerd"
62
63 struct consumer_data {
64 enum lttng_consumer_type type;
65
66 pthread_t thread; /* Worker thread interacting with the consumer */
67 sem_t sem;
68
69 /* Mutex to control consumerd pid assignation */
70 pthread_mutex_t pid_mutex;
71 pid_t pid;
72
73 int err_sock;
74 int cmd_sock;
75
76 /* consumer error and command Unix socket path */
77 char err_unix_sock_path[PATH_MAX];
78 char cmd_unix_sock_path[PATH_MAX];
79 };
80
81 /* Const values */
82 const char default_home_dir[] = DEFAULT_HOME_DIR;
83 const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
84 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
85 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
86
87 /* Variables */
88 int opt_verbose; /* Not static for lttngerr.h */
89 int opt_verbose_consumer; /* Not static for lttngerr.h */
90 int opt_quiet; /* Not static for lttngerr.h */
91
92 const char *progname;
93 const char *opt_tracing_group;
94 static int opt_sig_parent;
95 static int opt_daemon;
96 static int opt_no_kernel;
97 static int is_root; /* Set to 1 if the daemon is running as root */
98 static pid_t ppid; /* Parent PID for --sig-parent option */
99 static char *rundir;
100
101 /* Consumer daemon specific control data */
102 static struct consumer_data kconsumer_data = {
103 .type = LTTNG_CONSUMER_KERNEL,
104 .err_unix_sock_path = KCONSUMERD_ERR_SOCK_PATH,
105 .cmd_unix_sock_path = KCONSUMERD_CMD_SOCK_PATH,
106 };
107 static struct consumer_data ustconsumer64_data = {
108 .type = LTTNG_CONSUMER64_UST,
109 .err_unix_sock_path = USTCONSUMERD64_ERR_SOCK_PATH,
110 .cmd_unix_sock_path = USTCONSUMERD64_CMD_SOCK_PATH,
111 };
112 static struct consumer_data ustconsumer32_data = {
113 .type = LTTNG_CONSUMER32_UST,
114 .err_unix_sock_path = USTCONSUMERD32_ERR_SOCK_PATH,
115 .cmd_unix_sock_path = USTCONSUMERD32_CMD_SOCK_PATH,
116 };
117
118 static int dispatch_thread_exit;
119
120 /* Global application Unix socket path */
121 static char apps_unix_sock_path[PATH_MAX];
122 /* Global client Unix socket path */
123 static char client_unix_sock_path[PATH_MAX];
124 /* global wait shm path for UST */
125 static char wait_shm_path[PATH_MAX];
126
127 /* Sockets and FDs */
128 static int client_sock;
129 static int apps_sock;
130 static int kernel_tracer_fd;
131 static int kernel_poll_pipe[2];
132
133 /*
134 * Quit pipe for all threads. This permits a single cancellation point
135 * for all threads when receiving an event on the pipe.
136 */
137 static int thread_quit_pipe[2];
138
139 /*
140 * This pipe is used to inform the thread managing application communication
141 * that a command is queued and ready to be processed.
142 */
143 static int apps_cmd_pipe[2];
144
145 /* Pthread, Mutexes and Semaphores */
146 static pthread_t apps_thread;
147 static pthread_t reg_apps_thread;
148 static pthread_t client_thread;
149 static pthread_t kernel_thread;
150 static pthread_t dispatch_thread;
151
152
153 /*
154 * UST registration command queue. This queue is tied with a futex and uses a N
155 * wakers / 1 waiter implemented and detailed in futex.c/.h
156 *
157 * The thread_manage_apps and thread_dispatch_ust_registration interact with
158 * this queue and the wait/wake scheme.
159 */
160 static struct ust_cmd_queue ust_cmd_queue;
161
162 /*
163 * Pointer initialized before thread creation.
164 *
165 * This points to the tracing session list containing the session count and a
166 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
167 * MUST NOT be taken if you call a public function in session.c.
168 *
169 * The lock is nested inside the structure: session_list_ptr->lock. Please use
170 * session_lock_list and session_unlock_list for lock acquisition.
171 */
172 static struct ltt_session_list *session_list_ptr;
173
174 int ust_consumerd64_fd = -1;
175 int ust_consumerd32_fd = -1;
176
177 static const char *consumerd32_bin = CONFIG_CONSUMERD32_BIN;
178 static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
179 static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
180 static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
181
182 static
183 void setup_consumerd_path(void)
184 {
185 const char *bin, *libdir;
186
187 /*
188 * Allow INSTALL_BIN_PATH to be used as a target path for the
189 * native architecture size consumer if CONFIG_CONSUMER*_PATH
190 * has not been defined.
191 */
192 #if (CAA_BITS_PER_LONG == 32)
193 if (!consumerd32_bin[0]) {
194 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
195 }
196 if (!consumerd32_libdir[0]) {
197 consumerd32_libdir = INSTALL_LIB_PATH;
198 }
199 #elif (CAA_BITS_PER_LONG == 64)
200 if (!consumerd64_bin[0]) {
201 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
202 }
203 if (!consumerd64_libdir[0]) {
204 consumerd64_libdir = INSTALL_LIB_PATH;
205 }
206 #else
207 #error "Unknown bitness"
208 #endif
209
210 /*
211 * runtime env. var. overrides the build default.
212 */
213 bin = getenv("LTTNG_CONSUMERD32_BIN");
214 if (bin) {
215 consumerd32_bin = bin;
216 }
217 bin = getenv("LTTNG_CONSUMERD64_BIN");
218 if (bin) {
219 consumerd64_bin = bin;
220 }
221 libdir = getenv("LTTNG_TOOLS_CONSUMERD32_LIBDIR");
222 if (libdir) {
223 consumerd32_libdir = libdir;
224 }
225 libdir = getenv("LTTNG_TOOLS_CONSUMERD64_LIBDIR");
226 if (libdir) {
227 consumerd64_libdir = libdir;
228 }
229 }
230
231 /*
232 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
233 */
234 static int create_thread_poll_set(struct lttng_poll_event *events,
235 unsigned int size)
236 {
237 int ret;
238
239 if (events == NULL || size == 0) {
240 ret = -1;
241 goto error;
242 }
243
244 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
245 if (ret < 0) {
246 goto error;
247 }
248
249 /* Add quit pipe */
250 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
251 if (ret < 0) {
252 goto error;
253 }
254
255 return 0;
256
257 error:
258 return ret;
259 }
260
261 /*
262 * Check if the thread quit pipe was triggered.
263 *
264 * Return 1 if it was triggered else 0;
265 */
266 static int check_thread_quit_pipe(int fd, uint32_t events)
267 {
268 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
269 return 1;
270 }
271
272 return 0;
273 }
274
275 /*
276 * Remove modules in reverse load order.
277 */
278 static int modprobe_remove_kernel_modules(void)
279 {
280 int ret = 0, i;
281 char modprobe[256];
282
283 for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
284 ret = snprintf(modprobe, sizeof(modprobe),
285 "/sbin/modprobe -r -q %s",
286 kernel_modules_list[i].name);
287 if (ret < 0) {
288 perror("snprintf modprobe -r");
289 goto error;
290 }
291 modprobe[sizeof(modprobe) - 1] = '\0';
292 ret = system(modprobe);
293 if (ret == -1) {
294 ERR("Unable to launch modprobe -r for module %s",
295 kernel_modules_list[i].name);
296 } else if (kernel_modules_list[i].required
297 && WEXITSTATUS(ret) != 0) {
298 ERR("Unable to remove module %s",
299 kernel_modules_list[i].name);
300 } else {
301 DBG("Modprobe removal successful %s",
302 kernel_modules_list[i].name);
303 }
304 }
305
306 error:
307 return ret;
308 }
309
310 /*
311 * Return group ID of the tracing group or -1 if not found.
312 */
313 static gid_t allowed_group(void)
314 {
315 struct group *grp;
316
317 if (opt_tracing_group) {
318 grp = getgrnam(opt_tracing_group);
319 } else {
320 grp = getgrnam(default_tracing_group);
321 }
322 if (!grp) {
323 return -1;
324 } else {
325 return grp->gr_gid;
326 }
327 }
328
329 /*
330 * Init thread quit pipe.
331 *
332 * Return -1 on error or 0 if all pipes are created.
333 */
334 static int init_thread_quit_pipe(void)
335 {
336 int ret;
337
338 ret = pipe2(thread_quit_pipe, O_CLOEXEC);
339 if (ret < 0) {
340 perror("thread quit pipe");
341 goto error;
342 }
343
344 error:
345 return ret;
346 }
347
348 /*
349 * Complete teardown of a kernel session. This free all data structure related
350 * to a kernel session and update counter.
351 */
352 static void teardown_kernel_session(struct ltt_session *session)
353 {
354 if (!session->kernel_session) {
355 DBG3("No kernel session when tearingdown session");
356 return;
357 }
358
359 DBG("Tearing down kernel session");
360
361 /*
362 * If a custom kernel consumer was registered, close the socket before
363 * tearing down the complete kernel session structure
364 */
365 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
366 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
367 }
368
369 trace_kernel_destroy_session(session->kernel_session);
370 }
371
372 /*
373 * Complete teardown of all UST sessions. This will free everything on his path
374 * and destroy the core essence of all ust sessions :)
375 */
376 static void teardown_ust_session(struct ltt_session *session)
377 {
378 int ret;
379
380 if (!session->ust_session) {
381 DBG3("No UST session when tearingdown session");
382 return;
383 }
384
385 DBG("Tearing down UST session(s)");
386
387 ret = ust_app_destroy_trace_all(session->ust_session);
388 if (ret) {
389 ERR("Error in ust_app_destroy_trace_all");
390 }
391
392 trace_ust_destroy_session(session->ust_session);
393 }
394
395 /*
396 * Stop all threads by closing the thread quit pipe.
397 */
398 static void stop_threads(void)
399 {
400 int ret;
401
402 /* Stopping all threads */
403 DBG("Terminating all threads");
404 ret = notify_thread_pipe(thread_quit_pipe[1]);
405 if (ret < 0) {
406 ERR("write error on thread quit pipe");
407 }
408
409 /* Dispatch thread */
410 dispatch_thread_exit = 1;
411 futex_nto1_wake(&ust_cmd_queue.futex);
412 }
413
414 /*
415 * Cleanup the daemon
416 */
417 static void cleanup(void)
418 {
419 int ret;
420 char *cmd;
421 struct ltt_session *sess, *stmp;
422
423 DBG("Cleaning up");
424
425 DBG("Removing %s directory", rundir);
426 ret = asprintf(&cmd, "rm -rf %s", rundir);
427 if (ret < 0) {
428 ERR("asprintf failed. Something is really wrong!");
429 }
430
431 /* Remove lttng run directory */
432 ret = system(cmd);
433 if (ret < 0) {
434 ERR("Unable to clean %s", rundir);
435 }
436 free(cmd);
437
438 DBG("Cleaning up all session");
439
440 /* Destroy session list mutex */
441 if (session_list_ptr != NULL) {
442 pthread_mutex_destroy(&session_list_ptr->lock);
443
444 /* Cleanup ALL session */
445 cds_list_for_each_entry_safe(sess, stmp,
446 &session_list_ptr->head, list) {
447 teardown_kernel_session(sess);
448 teardown_ust_session(sess);
449 free(sess);
450 }
451 }
452
453 DBG("Closing all UST sockets");
454 ust_app_clean_list();
455
456 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
457
458 if (is_root && !opt_no_kernel) {
459 DBG2("Closing kernel fd");
460 close(kernel_tracer_fd);
461 DBG("Unloading kernel modules");
462 modprobe_remove_kernel_modules();
463 }
464
465 close(thread_quit_pipe[0]);
466 close(thread_quit_pipe[1]);
467
468 /* <fun> */
469 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
470 "Matthew, BEET driven development works!%c[%dm",
471 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
472 /* </fun> */
473 }
474
475 /*
476 * Send data on a unix socket using the liblttsessiondcomm API.
477 *
478 * Return lttcomm error code.
479 */
480 static int send_unix_sock(int sock, void *buf, size_t len)
481 {
482 /* Check valid length */
483 if (len <= 0) {
484 return -1;
485 }
486
487 return lttcomm_send_unix_sock(sock, buf, len);
488 }
489
490 /*
491 * Free memory of a command context structure.
492 */
493 static void clean_command_ctx(struct command_ctx **cmd_ctx)
494 {
495 DBG("Clean command context structure");
496 if (*cmd_ctx) {
497 if ((*cmd_ctx)->llm) {
498 free((*cmd_ctx)->llm);
499 }
500 if ((*cmd_ctx)->lsm) {
501 free((*cmd_ctx)->lsm);
502 }
503 free(*cmd_ctx);
504 *cmd_ctx = NULL;
505 }
506 }
507
508 /*
509 * Send all stream fds of kernel channel to the consumer.
510 */
511 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
512 int sock, struct ltt_kernel_channel *channel,
513 uid_t uid, gid_t gid)
514 {
515 int ret;
516 struct ltt_kernel_stream *stream;
517 struct lttcomm_consumer_msg lkm;
518
519 DBG("Sending streams of channel %s to kernel consumer",
520 channel->channel->name);
521
522 /* Send channel */
523 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
524 lkm.u.channel.channel_key = channel->fd;
525 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
526 lkm.u.channel.mmap_len = 0; /* for kernel */
527 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
528 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
529 if (ret < 0) {
530 perror("send consumer channel");
531 goto error;
532 }
533
534 /* Send streams */
535 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
536 if (!stream->fd) {
537 continue;
538 }
539 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
540 lkm.u.stream.channel_key = channel->fd;
541 lkm.u.stream.stream_key = stream->fd;
542 lkm.u.stream.state = stream->state;
543 lkm.u.stream.output = channel->channel->attr.output;
544 lkm.u.stream.mmap_len = 0; /* for kernel */
545 lkm.u.stream.uid = uid;
546 lkm.u.stream.gid = gid;
547 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
548 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
549 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
550 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
551 if (ret < 0) {
552 perror("send consumer stream");
553 goto error;
554 }
555 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
556 if (ret < 0) {
557 perror("send consumer stream ancillary data");
558 goto error;
559 }
560 }
561
562 DBG("consumer channel streams sent");
563
564 return 0;
565
566 error:
567 return ret;
568 }
569
570 /*
571 * Send all stream fds of the kernel session to the consumer.
572 */
573 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
574 struct ltt_kernel_session *session)
575 {
576 int ret;
577 struct ltt_kernel_channel *chan;
578 struct lttcomm_consumer_msg lkm;
579 int sock = session->consumer_fd;
580
581 DBG("Sending metadata stream fd");
582
583 /* Extra protection. It's NOT supposed to be set to 0 at this point */
584 if (session->consumer_fd == 0) {
585 session->consumer_fd = consumer_data->cmd_sock;
586 }
587
588 if (session->metadata_stream_fd != 0) {
589 /* Send metadata channel fd */
590 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
591 lkm.u.channel.channel_key = session->metadata->fd;
592 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
593 lkm.u.channel.mmap_len = 0; /* for kernel */
594 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
595 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
596 if (ret < 0) {
597 perror("send consumer channel");
598 goto error;
599 }
600
601 /* Send metadata stream fd */
602 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
603 lkm.u.stream.channel_key = session->metadata->fd;
604 lkm.u.stream.stream_key = session->metadata_stream_fd;
605 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
606 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
607 lkm.u.stream.mmap_len = 0; /* for kernel */
608 lkm.u.stream.uid = session->uid;
609 lkm.u.stream.gid = session->gid;
610 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
611 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
612 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
613 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
614 if (ret < 0) {
615 perror("send consumer stream");
616 goto error;
617 }
618 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
619 if (ret < 0) {
620 perror("send consumer stream");
621 goto error;
622 }
623 }
624
625 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
626 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
627 session->uid, session->gid);
628 if (ret < 0) {
629 goto error;
630 }
631 }
632
633 DBG("consumer fds (metadata and channel streams) sent");
634
635 return 0;
636
637 error:
638 return ret;
639 }
640
641 /*
642 * Notify UST applications using the shm mmap futex.
643 */
644 static int notify_ust_apps(int active)
645 {
646 char *wait_shm_mmap;
647
648 DBG("Notifying applications of session daemon state: %d", active);
649
650 /* See shm.c for this call implying mmap, shm and futex calls */
651 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
652 if (wait_shm_mmap == NULL) {
653 goto error;
654 }
655
656 /* Wake waiting process */
657 futex_wait_update((int32_t *) wait_shm_mmap, active);
658
659 /* Apps notified successfully */
660 return 0;
661
662 error:
663 return -1;
664 }
665
666 /*
667 * Setup the outgoing data buffer for the response (llm) by allocating the
668 * right amount of memory and copying the original information from the lsm
669 * structure.
670 *
671 * Return total size of the buffer pointed by buf.
672 */
673 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
674 {
675 int ret, buf_size;
676
677 buf_size = size;
678
679 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
680 if (cmd_ctx->llm == NULL) {
681 perror("zmalloc");
682 ret = -ENOMEM;
683 goto error;
684 }
685
686 /* Copy common data */
687 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
688 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
689
690 cmd_ctx->llm->data_size = size;
691 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
692
693 return buf_size;
694
695 error:
696 return ret;
697 }
698
699 /*
700 * Update the kernel poll set of all channel fd available over all tracing
701 * session. Add the wakeup pipe at the end of the set.
702 */
703 static int update_kernel_poll(struct lttng_poll_event *events)
704 {
705 int ret;
706 struct ltt_session *session;
707 struct ltt_kernel_channel *channel;
708
709 DBG("Updating kernel poll set");
710
711 session_lock_list();
712 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
713 session_lock(session);
714 if (session->kernel_session == NULL) {
715 session_unlock(session);
716 continue;
717 }
718
719 cds_list_for_each_entry(channel,
720 &session->kernel_session->channel_list.head, list) {
721 /* Add channel fd to the kernel poll set */
722 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
723 if (ret < 0) {
724 session_unlock(session);
725 goto error;
726 }
727 DBG("Channel fd %d added to kernel set", channel->fd);
728 }
729 session_unlock(session);
730 }
731 session_unlock_list();
732
733 return 0;
734
735 error:
736 session_unlock_list();
737 return -1;
738 }
739
740 /*
741 * Find the channel fd from 'fd' over all tracing session. When found, check
742 * for new channel stream and send those stream fds to the kernel consumer.
743 *
744 * Useful for CPU hotplug feature.
745 */
746 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
747 {
748 int ret = 0;
749 struct ltt_session *session;
750 struct ltt_kernel_channel *channel;
751
752 DBG("Updating kernel streams for channel fd %d", fd);
753
754 session_lock_list();
755 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
756 session_lock(session);
757 if (session->kernel_session == NULL) {
758 session_unlock(session);
759 continue;
760 }
761
762 /* This is not suppose to be 0 but this is an extra security check */
763 if (session->kernel_session->consumer_fd == 0) {
764 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
765 }
766
767 cds_list_for_each_entry(channel,
768 &session->kernel_session->channel_list.head, list) {
769 if (channel->fd == fd) {
770 DBG("Channel found, updating kernel streams");
771 ret = kernel_open_channel_stream(channel);
772 if (ret < 0) {
773 goto error;
774 }
775
776 /*
777 * Have we already sent fds to the consumer? If yes, it means
778 * that tracing is started so it is safe to send our updated
779 * stream fds.
780 */
781 if (session->kernel_session->consumer_fds_sent == 1) {
782 ret = send_kconsumer_channel_streams(consumer_data,
783 session->kernel_session->consumer_fd, channel,
784 session->uid, session->gid);
785 if (ret < 0) {
786 goto error;
787 }
788 }
789 goto error;
790 }
791 }
792 session_unlock(session);
793 }
794 session_unlock_list();
795 return ret;
796
797 error:
798 session_unlock(session);
799 session_unlock_list();
800 return ret;
801 }
802
803 /*
804 * For each tracing session, update newly registered apps.
805 */
806 static void update_ust_app(int app_sock)
807 {
808 struct ltt_session *sess, *stmp;
809
810 /* For all tracing session(s) */
811 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
812 if (sess->ust_session) {
813 ust_app_global_update(sess->ust_session, app_sock);
814 }
815 }
816 }
817
818 /*
819 * This thread manage event coming from the kernel.
820 *
821 * Features supported in this thread:
822 * -) CPU Hotplug
823 */
824 static void *thread_manage_kernel(void *data)
825 {
826 int ret, i, pollfd, update_poll_flag = 1;
827 uint32_t revents, nb_fd;
828 char tmp;
829 struct lttng_poll_event events;
830
831 DBG("Thread manage kernel started");
832
833 ret = create_thread_poll_set(&events, 2);
834 if (ret < 0) {
835 goto error;
836 }
837
838 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
839 if (ret < 0) {
840 goto error;
841 }
842
843 while (1) {
844 if (update_poll_flag == 1) {
845 /*
846 * Reset number of fd in the poll set. Always 2 since there is the thread
847 * quit pipe and the kernel pipe.
848 */
849 events.nb_fd = 2;
850
851 ret = update_kernel_poll(&events);
852 if (ret < 0) {
853 goto error;
854 }
855 update_poll_flag = 0;
856 }
857
858 nb_fd = LTTNG_POLL_GETNB(&events);
859
860 DBG("Thread kernel polling on %d fds", nb_fd);
861
862 /* Zeroed the poll events */
863 lttng_poll_reset(&events);
864
865 /* Poll infinite value of time */
866 ret = lttng_poll_wait(&events, -1);
867 if (ret < 0) {
868 goto error;
869 } else if (ret == 0) {
870 /* Should not happen since timeout is infinite */
871 ERR("Return value of poll is 0 with an infinite timeout.\n"
872 "This should not have happened! Continuing...");
873 continue;
874 }
875
876 for (i = 0; i < nb_fd; i++) {
877 /* Fetch once the poll data */
878 revents = LTTNG_POLL_GETEV(&events, i);
879 pollfd = LTTNG_POLL_GETFD(&events, i);
880
881 /* Thread quit pipe has been closed. Killing thread. */
882 ret = check_thread_quit_pipe(pollfd, revents);
883 if (ret) {
884 goto error;
885 }
886
887 /* Check for data on kernel pipe */
888 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
889 ret = read(kernel_poll_pipe[0], &tmp, 1);
890 update_poll_flag = 1;
891 continue;
892 } else {
893 /*
894 * New CPU detected by the kernel. Adding kernel stream to
895 * kernel session and updating the kernel consumer
896 */
897 if (revents & LPOLLIN) {
898 ret = update_kernel_stream(&kconsumer_data, pollfd);
899 if (ret < 0) {
900 continue;
901 }
902 break;
903 /*
904 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
905 * and unregister kernel stream at this point.
906 */
907 }
908 }
909 }
910 }
911
912 error:
913 DBG("Kernel thread dying");
914 close(kernel_poll_pipe[0]);
915 close(kernel_poll_pipe[1]);
916
917 lttng_poll_clean(&events);
918
919 return NULL;
920 }
921
922 /*
923 * This thread manage the consumer error sent back to the session daemon.
924 */
925 static void *thread_manage_consumer(void *data)
926 {
927 int sock = 0, i, ret, pollfd;
928 uint32_t revents, nb_fd;
929 enum lttcomm_return_code code;
930 struct lttng_poll_event events;
931 struct consumer_data *consumer_data = data;
932
933 DBG("[thread] Manage consumer started");
934
935 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
936 if (ret < 0) {
937 goto error;
938 }
939
940 /*
941 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
942 * Nothing more will be added to this poll set.
943 */
944 ret = create_thread_poll_set(&events, 2);
945 if (ret < 0) {
946 goto error;
947 }
948
949 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
950 if (ret < 0) {
951 goto error;
952 }
953
954 nb_fd = LTTNG_POLL_GETNB(&events);
955
956 /* Inifinite blocking call, waiting for transmission */
957 ret = lttng_poll_wait(&events, -1);
958 if (ret < 0) {
959 goto error;
960 }
961
962 for (i = 0; i < nb_fd; i++) {
963 /* Fetch once the poll data */
964 revents = LTTNG_POLL_GETEV(&events, i);
965 pollfd = LTTNG_POLL_GETFD(&events, i);
966
967 /* Thread quit pipe has been closed. Killing thread. */
968 ret = check_thread_quit_pipe(pollfd, revents);
969 if (ret) {
970 goto error;
971 }
972
973 /* Event on the registration socket */
974 if (pollfd == consumer_data->err_sock) {
975 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
976 ERR("consumer err socket poll error");
977 goto error;
978 }
979 }
980 }
981
982 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
983 if (sock < 0) {
984 goto error;
985 }
986
987 DBG2("Receiving code from consumer err_sock");
988
989 /* Getting status code from kconsumerd */
990 ret = lttcomm_recv_unix_sock(sock, &code,
991 sizeof(enum lttcomm_return_code));
992 if (ret <= 0) {
993 goto error;
994 }
995
996 if (code == CONSUMERD_COMMAND_SOCK_READY) {
997 consumer_data->cmd_sock =
998 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
999 if (consumer_data->cmd_sock < 0) {
1000 sem_post(&consumer_data->sem);
1001 PERROR("consumer connect");
1002 goto error;
1003 }
1004 /* Signal condition to tell that the kconsumerd is ready */
1005 sem_post(&consumer_data->sem);
1006 DBG("consumer command socket ready");
1007 } else {
1008 ERR("consumer error when waiting for SOCK_READY : %s",
1009 lttcomm_get_readable_code(-code));
1010 goto error;
1011 }
1012
1013 /* Remove the kconsumerd error sock since we've established a connexion */
1014 ret = lttng_poll_del(&events, consumer_data->err_sock);
1015 if (ret < 0) {
1016 goto error;
1017 }
1018
1019 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1020 if (ret < 0) {
1021 goto error;
1022 }
1023
1024 /* Update number of fd */
1025 nb_fd = LTTNG_POLL_GETNB(&events);
1026
1027 /* Inifinite blocking call, waiting for transmission */
1028 ret = lttng_poll_wait(&events, -1);
1029 if (ret < 0) {
1030 goto error;
1031 }
1032
1033 for (i = 0; i < nb_fd; i++) {
1034 /* Fetch once the poll data */
1035 revents = LTTNG_POLL_GETEV(&events, i);
1036 pollfd = LTTNG_POLL_GETFD(&events, i);
1037
1038 /* Thread quit pipe has been closed. Killing thread. */
1039 ret = check_thread_quit_pipe(pollfd, revents);
1040 if (ret) {
1041 goto error;
1042 }
1043
1044 /* Event on the kconsumerd socket */
1045 if (pollfd == sock) {
1046 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1047 ERR("consumer err socket second poll error");
1048 goto error;
1049 }
1050 }
1051 }
1052
1053 /* Wait for any kconsumerd error */
1054 ret = lttcomm_recv_unix_sock(sock, &code,
1055 sizeof(enum lttcomm_return_code));
1056 if (ret <= 0) {
1057 ERR("consumer closed the command socket");
1058 goto error;
1059 }
1060
1061 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1062
1063 error:
1064 DBG("consumer thread dying");
1065 close(consumer_data->err_sock);
1066 close(consumer_data->cmd_sock);
1067 close(sock);
1068
1069 unlink(consumer_data->err_unix_sock_path);
1070 unlink(consumer_data->cmd_unix_sock_path);
1071 consumer_data->pid = 0;
1072
1073 lttng_poll_clean(&events);
1074
1075 return NULL;
1076 }
1077
1078 /*
1079 * This thread manage application communication.
1080 */
1081 static void *thread_manage_apps(void *data)
1082 {
1083 int i, ret, pollfd;
1084 uint32_t revents, nb_fd;
1085 struct ust_command ust_cmd;
1086 struct lttng_poll_event events;
1087
1088 DBG("[thread] Manage application started");
1089
1090 rcu_register_thread();
1091 rcu_thread_online();
1092
1093 ret = create_thread_poll_set(&events, 2);
1094 if (ret < 0) {
1095 goto error;
1096 }
1097
1098 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1099 if (ret < 0) {
1100 goto error;
1101 }
1102
1103 while (1) {
1104 /* Zeroed the events structure */
1105 lttng_poll_reset(&events);
1106
1107 nb_fd = LTTNG_POLL_GETNB(&events);
1108
1109 DBG("Apps thread polling on %d fds", nb_fd);
1110
1111 /* Inifinite blocking call, waiting for transmission */
1112 ret = lttng_poll_wait(&events, -1);
1113 if (ret < 0) {
1114 goto error;
1115 }
1116
1117 for (i = 0; i < nb_fd; i++) {
1118 /* Fetch once the poll data */
1119 revents = LTTNG_POLL_GETEV(&events, i);
1120 pollfd = LTTNG_POLL_GETFD(&events, i);
1121
1122 /* Thread quit pipe has been closed. Killing thread. */
1123 ret = check_thread_quit_pipe(pollfd, revents);
1124 if (ret) {
1125 goto error;
1126 }
1127
1128 /* Inspect the apps cmd pipe */
1129 if (pollfd == apps_cmd_pipe[0]) {
1130 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1131 ERR("Apps command pipe error");
1132 goto error;
1133 } else if (revents & LPOLLIN) {
1134 /* Empty pipe */
1135 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1136 if (ret < 0 || ret < sizeof(ust_cmd)) {
1137 perror("read apps cmd pipe");
1138 goto error;
1139 }
1140
1141 /* Register applicaton to the session daemon */
1142 ret = ust_app_register(&ust_cmd.reg_msg,
1143 ust_cmd.sock);
1144 if (ret == -ENOMEM) {
1145 goto error;
1146 } else if (ret < 0) {
1147 break;
1148 }
1149
1150 /*
1151 * Add channel(s) and event(s) to newly registered apps
1152 * from lttng global UST domain.
1153 */
1154 update_ust_app(ust_cmd.sock);
1155
1156 ret = ust_app_register_done(ust_cmd.sock);
1157 if (ret < 0) {
1158 /*
1159 * If the registration is not possible, we simply
1160 * unregister the apps and continue
1161 */
1162 ust_app_unregister(ust_cmd.sock);
1163 } else {
1164 /*
1165 * We just need here to monitor the close of the UST
1166 * socket and poll set monitor those by default.
1167 */
1168 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1169 if (ret < 0) {
1170 goto error;
1171 }
1172
1173 DBG("Apps with sock %d added to poll set",
1174 ust_cmd.sock);
1175 }
1176
1177 break;
1178 }
1179 } else {
1180 /*
1181 * At this point, we know that a registered application made
1182 * the event at poll_wait.
1183 */
1184 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1185 /* Removing from the poll set */
1186 ret = lttng_poll_del(&events, pollfd);
1187 if (ret < 0) {
1188 goto error;
1189 }
1190
1191 /* Socket closed on remote end. */
1192 ust_app_unregister(pollfd);
1193 break;
1194 }
1195 }
1196 }
1197 }
1198
1199 error:
1200 DBG("Application communication apps dying");
1201 close(apps_cmd_pipe[0]);
1202 close(apps_cmd_pipe[1]);
1203
1204 lttng_poll_clean(&events);
1205
1206 rcu_thread_offline();
1207 rcu_unregister_thread();
1208 return NULL;
1209 }
1210
1211 /*
1212 * Dispatch request from the registration threads to the application
1213 * communication thread.
1214 */
1215 static void *thread_dispatch_ust_registration(void *data)
1216 {
1217 int ret;
1218 struct cds_wfq_node *node;
1219 struct ust_command *ust_cmd = NULL;
1220
1221 DBG("[thread] Dispatch UST command started");
1222
1223 while (!dispatch_thread_exit) {
1224 /* Atomically prepare the queue futex */
1225 futex_nto1_prepare(&ust_cmd_queue.futex);
1226
1227 do {
1228 /* Dequeue command for registration */
1229 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1230 if (node == NULL) {
1231 DBG("Woken up but nothing in the UST command queue");
1232 /* Continue thread execution */
1233 break;
1234 }
1235
1236 ust_cmd = caa_container_of(node, struct ust_command, node);
1237
1238 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1239 " gid:%d sock:%d name:%s (version %d.%d)",
1240 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1241 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1242 ust_cmd->sock, ust_cmd->reg_msg.name,
1243 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1244 /*
1245 * Inform apps thread of the new application registration. This
1246 * call is blocking so we can be assured that the data will be read
1247 * at some point in time or wait to the end of the world :)
1248 */
1249 ret = write(apps_cmd_pipe[1], ust_cmd,
1250 sizeof(struct ust_command));
1251 if (ret < 0) {
1252 perror("write apps cmd pipe");
1253 if (errno == EBADF) {
1254 /*
1255 * We can't inform the application thread to process
1256 * registration. We will exit or else application
1257 * registration will not occur and tracing will never
1258 * start.
1259 */
1260 goto error;
1261 }
1262 }
1263 free(ust_cmd);
1264 } while (node != NULL);
1265
1266 /* Futex wait on queue. Blocking call on futex() */
1267 futex_nto1_wait(&ust_cmd_queue.futex);
1268 }
1269
1270 error:
1271 DBG("Dispatch thread dying");
1272 return NULL;
1273 }
1274
1275 /*
1276 * This thread manage application registration.
1277 */
1278 static void *thread_registration_apps(void *data)
1279 {
1280 int sock = 0, i, ret, pollfd;
1281 uint32_t revents, nb_fd;
1282 struct lttng_poll_event events;
1283 /*
1284 * Get allocated in this thread, enqueued to a global queue, dequeued and
1285 * freed in the manage apps thread.
1286 */
1287 struct ust_command *ust_cmd = NULL;
1288
1289 DBG("[thread] Manage application registration started");
1290
1291 ret = lttcomm_listen_unix_sock(apps_sock);
1292 if (ret < 0) {
1293 goto error;
1294 }
1295
1296 /*
1297 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1298 * more will be added to this poll set.
1299 */
1300 ret = create_thread_poll_set(&events, 2);
1301 if (ret < 0) {
1302 goto error;
1303 }
1304
1305 /* Add the application registration socket */
1306 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1307 if (ret < 0) {
1308 goto error;
1309 }
1310
1311 /* Notify all applications to register */
1312 ret = notify_ust_apps(1);
1313 if (ret < 0) {
1314 ERR("Failed to notify applications or create the wait shared memory.\n"
1315 "Execution continues but there might be problem for already\n"
1316 "running applications that wishes to register.");
1317 }
1318
1319 while (1) {
1320 DBG("Accepting application registration");
1321
1322 nb_fd = LTTNG_POLL_GETNB(&events);
1323
1324 /* Inifinite blocking call, waiting for transmission */
1325 ret = lttng_poll_wait(&events, -1);
1326 if (ret < 0) {
1327 goto error;
1328 }
1329
1330 for (i = 0; i < nb_fd; i++) {
1331 /* Fetch once the poll data */
1332 revents = LTTNG_POLL_GETEV(&events, i);
1333 pollfd = LTTNG_POLL_GETFD(&events, i);
1334
1335 /* Thread quit pipe has been closed. Killing thread. */
1336 ret = check_thread_quit_pipe(pollfd, revents);
1337 if (ret) {
1338 goto error;
1339 }
1340
1341 /* Event on the registration socket */
1342 if (pollfd == apps_sock) {
1343 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1344 ERR("Register apps socket poll error");
1345 goto error;
1346 } else if (revents & LPOLLIN) {
1347 sock = lttcomm_accept_unix_sock(apps_sock);
1348 if (sock < 0) {
1349 goto error;
1350 }
1351
1352 /* Create UST registration command for enqueuing */
1353 ust_cmd = zmalloc(sizeof(struct ust_command));
1354 if (ust_cmd == NULL) {
1355 perror("ust command zmalloc");
1356 goto error;
1357 }
1358
1359 /*
1360 * Using message-based transmissions to ensure we don't
1361 * have to deal with partially received messages.
1362 */
1363 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1364 sizeof(struct ust_register_msg));
1365 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1366 if (ret < 0) {
1367 perror("lttcomm_recv_unix_sock register apps");
1368 } else {
1369 ERR("Wrong size received on apps register");
1370 }
1371 free(ust_cmd);
1372 close(sock);
1373 continue;
1374 }
1375
1376 ust_cmd->sock = sock;
1377
1378 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1379 " gid:%d sock:%d name:%s (version %d.%d)",
1380 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1381 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1382 ust_cmd->sock, ust_cmd->reg_msg.name,
1383 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1384
1385 /*
1386 * Lock free enqueue the registration request. The red pill
1387 * has been taken! This apps will be part of the *system*.
1388 */
1389 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1390
1391 /*
1392 * Wake the registration queue futex. Implicit memory
1393 * barrier with the exchange in cds_wfq_enqueue.
1394 */
1395 futex_nto1_wake(&ust_cmd_queue.futex);
1396 }
1397 }
1398 }
1399 }
1400
1401 error:
1402 DBG("UST Registration thread dying");
1403
1404 /* Notify that the registration thread is gone */
1405 notify_ust_apps(0);
1406
1407 close(apps_sock);
1408 close(sock);
1409 unlink(apps_unix_sock_path);
1410
1411 lttng_poll_clean(&events);
1412
1413 return NULL;
1414 }
1415
1416 /*
1417 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1418 * exec or it will fails.
1419 */
1420 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1421 {
1422 int ret;
1423 struct timespec timeout;
1424
1425 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1426 timeout.tv_nsec = 0;
1427
1428 /* Setup semaphore */
1429 ret = sem_init(&consumer_data->sem, 0, 0);
1430 if (ret < 0) {
1431 PERROR("sem_init consumer semaphore");
1432 goto error;
1433 }
1434
1435 ret = pthread_create(&consumer_data->thread, NULL,
1436 thread_manage_consumer, consumer_data);
1437 if (ret != 0) {
1438 PERROR("pthread_create consumer");
1439 ret = -1;
1440 goto error;
1441 }
1442
1443 /* Get time for sem_timedwait absolute timeout */
1444 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1445 if (ret < 0) {
1446 PERROR("clock_gettime spawn consumer");
1447 /* Infinite wait for the kconsumerd thread to be ready */
1448 ret = sem_wait(&consumer_data->sem);
1449 } else {
1450 /* Normal timeout if the gettime was successful */
1451 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1452 ret = sem_timedwait(&consumer_data->sem, &timeout);
1453 }
1454
1455 if (ret < 0) {
1456 if (errno == ETIMEDOUT) {
1457 /*
1458 * Call has timed out so we kill the kconsumerd_thread and return
1459 * an error.
1460 */
1461 ERR("The consumer thread was never ready. Killing it");
1462 ret = pthread_cancel(consumer_data->thread);
1463 if (ret < 0) {
1464 PERROR("pthread_cancel consumer thread");
1465 }
1466 } else {
1467 PERROR("semaphore wait failed consumer thread");
1468 }
1469 goto error;
1470 }
1471
1472 pthread_mutex_lock(&consumer_data->pid_mutex);
1473 if (consumer_data->pid == 0) {
1474 ERR("Kconsumerd did not start");
1475 pthread_mutex_unlock(&consumer_data->pid_mutex);
1476 goto error;
1477 }
1478 pthread_mutex_unlock(&consumer_data->pid_mutex);
1479
1480 return 0;
1481
1482 error:
1483 return ret;
1484 }
1485
1486 /*
1487 * Join consumer thread
1488 */
1489 static int join_consumer_thread(struct consumer_data *consumer_data)
1490 {
1491 void *status;
1492 int ret;
1493
1494 if (consumer_data->pid != 0) {
1495 ret = kill(consumer_data->pid, SIGTERM);
1496 if (ret) {
1497 ERR("Error killing consumer daemon");
1498 return ret;
1499 }
1500 return pthread_join(consumer_data->thread, &status);
1501 } else {
1502 return 0;
1503 }
1504 }
1505
1506 /*
1507 * Fork and exec a consumer daemon (consumerd).
1508 *
1509 * Return pid if successful else -1.
1510 */
1511 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1512 {
1513 int ret;
1514 pid_t pid;
1515 const char *consumer_to_use;
1516 const char *verbosity;
1517 struct stat st;
1518
1519 DBG("Spawning consumerd");
1520
1521 pid = fork();
1522 if (pid == 0) {
1523 /*
1524 * Exec consumerd.
1525 */
1526 if (opt_verbose_consumer) {
1527 verbosity = "--verbose";
1528 } else {
1529 verbosity = "--quiet";
1530 }
1531 switch (consumer_data->type) {
1532 case LTTNG_CONSUMER_KERNEL:
1533 /*
1534 * Find out which consumerd to execute. We will first try the
1535 * 64-bit path, then the sessiond's installation directory, and
1536 * fallback on the 32-bit one,
1537 */
1538 DBG3("Looking for a kernel consumer at these locations:");
1539 DBG3(" 1) %s", consumerd64_bin);
1540 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1541 DBG3(" 3) %s", consumerd32_bin);
1542 if (stat(consumerd64_bin, &st) == 0) {
1543 DBG3("Found location #1");
1544 consumer_to_use = consumerd64_bin;
1545 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1546 DBG3("Found location #2");
1547 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1548 } else if (stat(consumerd32_bin, &st) == 0) {
1549 DBG3("Found location #3");
1550 consumer_to_use = consumerd32_bin;
1551 } else {
1552 DBG("Could not find any valid consumerd executable");
1553 break;
1554 }
1555 DBG("Using kernel consumer at: %s", consumer_to_use);
1556 execl(consumer_to_use,
1557 "lttng-consumerd", verbosity, "-k",
1558 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1559 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1560 NULL);
1561 break;
1562 case LTTNG_CONSUMER64_UST:
1563 {
1564 char *tmpnew = NULL;
1565
1566 if (consumerd64_libdir[0] != '\0') {
1567 char *tmp;
1568 size_t tmplen;
1569
1570 tmp = getenv("LD_LIBRARY_PATH");
1571 if (!tmp) {
1572 tmp = "";
1573 }
1574 tmplen = strlen("LD_LIBRARY_PATH=")
1575 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1576 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1577 if (!tmpnew) {
1578 ret = -ENOMEM;
1579 goto error;
1580 }
1581 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1582 strcat(tmpnew, consumerd64_libdir);
1583 if (tmp[0] != '\0') {
1584 strcat(tmpnew, ":");
1585 strcat(tmpnew, tmp);
1586 }
1587 ret = putenv(tmpnew);
1588 if (ret) {
1589 ret = -errno;
1590 goto error;
1591 }
1592 }
1593 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1594 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1595 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1596 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1597 NULL);
1598 if (consumerd64_libdir[0] != '\0') {
1599 free(tmpnew);
1600 }
1601 if (ret) {
1602 goto error;
1603 }
1604 break;
1605 }
1606 case LTTNG_CONSUMER32_UST:
1607 {
1608 char *tmpnew = NULL;
1609
1610 if (consumerd32_libdir[0] != '\0') {
1611 char *tmp;
1612 size_t tmplen;
1613
1614 tmp = getenv("LD_LIBRARY_PATH");
1615 if (!tmp) {
1616 tmp = "";
1617 }
1618 tmplen = strlen("LD_LIBRARY_PATH=")
1619 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1620 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1621 if (!tmpnew) {
1622 ret = -ENOMEM;
1623 goto error;
1624 }
1625 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1626 strcat(tmpnew, consumerd32_libdir);
1627 if (tmp[0] != '\0') {
1628 strcat(tmpnew, ":");
1629 strcat(tmpnew, tmp);
1630 }
1631 ret = putenv(tmpnew);
1632 if (ret) {
1633 ret = -errno;
1634 goto error;
1635 }
1636 }
1637 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1638 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1639 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1640 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1641 NULL);
1642 if (consumerd32_libdir[0] != '\0') {
1643 free(tmpnew);
1644 }
1645 if (ret) {
1646 goto error;
1647 }
1648 break;
1649 }
1650 default:
1651 perror("unknown consumer type");
1652 exit(EXIT_FAILURE);
1653 }
1654 if (errno != 0) {
1655 perror("kernel start consumer exec");
1656 }
1657 exit(EXIT_FAILURE);
1658 } else if (pid > 0) {
1659 ret = pid;
1660 } else {
1661 perror("start consumer fork");
1662 ret = -errno;
1663 }
1664 error:
1665 return ret;
1666 }
1667
1668 /*
1669 * Spawn the consumerd daemon and session daemon thread.
1670 */
1671 static int start_consumerd(struct consumer_data *consumer_data)
1672 {
1673 int ret;
1674
1675 pthread_mutex_lock(&consumer_data->pid_mutex);
1676 if (consumer_data->pid != 0) {
1677 pthread_mutex_unlock(&consumer_data->pid_mutex);
1678 goto end;
1679 }
1680
1681 ret = spawn_consumerd(consumer_data);
1682 if (ret < 0) {
1683 ERR("Spawning consumerd failed");
1684 pthread_mutex_unlock(&consumer_data->pid_mutex);
1685 goto error;
1686 }
1687
1688 /* Setting up the consumer_data pid */
1689 consumer_data->pid = ret;
1690 DBG2("Consumer pid %d", consumer_data->pid);
1691 pthread_mutex_unlock(&consumer_data->pid_mutex);
1692
1693 DBG2("Spawning consumer control thread");
1694 ret = spawn_consumer_thread(consumer_data);
1695 if (ret < 0) {
1696 ERR("Fatal error spawning consumer control thread");
1697 goto error;
1698 }
1699
1700 end:
1701 return 0;
1702
1703 error:
1704 return ret;
1705 }
1706
1707 /*
1708 * modprobe_kernel_modules
1709 */
1710 static int modprobe_kernel_modules(void)
1711 {
1712 int ret = 0, i;
1713 char modprobe[256];
1714
1715 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1716 ret = snprintf(modprobe, sizeof(modprobe),
1717 "/sbin/modprobe %s%s",
1718 kernel_modules_list[i].required ? "" : "-q ",
1719 kernel_modules_list[i].name);
1720 if (ret < 0) {
1721 perror("snprintf modprobe");
1722 goto error;
1723 }
1724 modprobe[sizeof(modprobe) - 1] = '\0';
1725 ret = system(modprobe);
1726 if (ret == -1) {
1727 ERR("Unable to launch modprobe for module %s",
1728 kernel_modules_list[i].name);
1729 } else if (kernel_modules_list[i].required
1730 && WEXITSTATUS(ret) != 0) {
1731 ERR("Unable to load module %s",
1732 kernel_modules_list[i].name);
1733 } else {
1734 DBG("Modprobe successfully %s",
1735 kernel_modules_list[i].name);
1736 }
1737 }
1738
1739 error:
1740 return ret;
1741 }
1742
1743 /*
1744 * mount_debugfs
1745 */
1746 static int mount_debugfs(char *path)
1747 {
1748 int ret;
1749 char *type = "debugfs";
1750
1751 ret = run_as_mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1752 if (ret < 0) {
1753 PERROR("Cannot create debugfs path");
1754 goto error;
1755 }
1756
1757 ret = mount(type, path, type, 0, NULL);
1758 if (ret < 0) {
1759 PERROR("Cannot mount debugfs");
1760 goto error;
1761 }
1762
1763 DBG("Mounted debugfs successfully at %s", path);
1764
1765 error:
1766 return ret;
1767 }
1768
1769 /*
1770 * Setup necessary data for kernel tracer action.
1771 */
1772 static void init_kernel_tracer(void)
1773 {
1774 int ret;
1775 char *proc_mounts = "/proc/mounts";
1776 char line[256];
1777 char *debugfs_path = NULL, *lttng_path = NULL;
1778 FILE *fp;
1779
1780 /* Detect debugfs */
1781 fp = fopen(proc_mounts, "r");
1782 if (fp == NULL) {
1783 ERR("Unable to probe %s", proc_mounts);
1784 goto error;
1785 }
1786
1787 while (fgets(line, sizeof(line), fp) != NULL) {
1788 if (strstr(line, "debugfs") != NULL) {
1789 /* Remove first string */
1790 strtok(line, " ");
1791 /* Dup string here so we can reuse line later on */
1792 debugfs_path = strdup(strtok(NULL, " "));
1793 DBG("Got debugfs path : %s", debugfs_path);
1794 break;
1795 }
1796 }
1797
1798 fclose(fp);
1799
1800 /* Mount debugfs if needded */
1801 if (debugfs_path == NULL) {
1802 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1803 if (ret < 0) {
1804 perror("asprintf debugfs path");
1805 goto error;
1806 }
1807 ret = mount_debugfs(debugfs_path);
1808 if (ret < 0) {
1809 perror("Cannot mount debugfs");
1810 goto error;
1811 }
1812 }
1813
1814 /* Modprobe lttng kernel modules */
1815 ret = modprobe_kernel_modules();
1816 if (ret < 0) {
1817 goto error;
1818 }
1819
1820 /* Setup lttng kernel path */
1821 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1822 if (ret < 0) {
1823 perror("asprintf lttng path");
1824 goto error;
1825 }
1826
1827 /* Open debugfs lttng */
1828 kernel_tracer_fd = open(lttng_path, O_RDWR);
1829 if (kernel_tracer_fd < 0) {
1830 DBG("Failed to open %s", lttng_path);
1831 goto error;
1832 }
1833
1834 free(lttng_path);
1835 free(debugfs_path);
1836 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1837 return;
1838
1839 error:
1840 if (lttng_path) {
1841 free(lttng_path);
1842 }
1843 if (debugfs_path) {
1844 free(debugfs_path);
1845 }
1846 WARN("No kernel tracer available");
1847 kernel_tracer_fd = 0;
1848 return;
1849 }
1850
1851 /*
1852 * Init tracing by creating trace directory and sending fds kernel consumer.
1853 */
1854 static int init_kernel_tracing(struct ltt_kernel_session *session)
1855 {
1856 int ret = 0;
1857
1858 if (session->consumer_fds_sent == 0) {
1859 /*
1860 * Assign default kernel consumer socket if no consumer assigned to the
1861 * kernel session. At this point, it's NOT suppose to be 0 but this is
1862 * an extra security check.
1863 */
1864 if (session->consumer_fd == 0) {
1865 session->consumer_fd = kconsumer_data.cmd_sock;
1866 }
1867
1868 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1869 if (ret < 0) {
1870 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1871 goto error;
1872 }
1873
1874 session->consumer_fds_sent = 1;
1875 }
1876
1877 error:
1878 return ret;
1879 }
1880
1881 /*
1882 * Create an UST session and add it to the session ust list.
1883 */
1884 static int create_ust_session(struct ltt_session *session,
1885 struct lttng_domain *domain)
1886 {
1887 struct ltt_ust_session *lus = NULL;
1888 int ret;
1889
1890 switch (domain->type) {
1891 case LTTNG_DOMAIN_UST:
1892 break;
1893 default:
1894 ret = LTTCOMM_UNKNOWN_DOMAIN;
1895 goto error;
1896 }
1897
1898 DBG("Creating UST session");
1899
1900 lus = trace_ust_create_session(session->path, session->id, domain);
1901 if (lus == NULL) {
1902 ret = LTTCOMM_UST_SESS_FAIL;
1903 goto error;
1904 }
1905
1906 ret = run_as_mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1907 session->uid, session->gid);
1908 if (ret < 0) {
1909 if (ret != -EEXIST) {
1910 ERR("Trace directory creation error");
1911 ret = LTTCOMM_UST_SESS_FAIL;
1912 goto error;
1913 }
1914 }
1915
1916 /* The domain type dictate different actions on session creation */
1917 switch (domain->type) {
1918 case LTTNG_DOMAIN_UST:
1919 /* No ustctl for the global UST domain */
1920 break;
1921 default:
1922 ERR("Unknown UST domain on create session %d", domain->type);
1923 goto error;
1924 }
1925 lus->uid = session->uid;
1926 lus->gid = session->gid;
1927 session->ust_session = lus;
1928
1929 return LTTCOMM_OK;
1930
1931 error:
1932 free(lus);
1933 return ret;
1934 }
1935
1936 /*
1937 * Create a kernel tracer session then create the default channel.
1938 */
1939 static int create_kernel_session(struct ltt_session *session)
1940 {
1941 int ret;
1942
1943 DBG("Creating kernel session");
1944
1945 ret = kernel_create_session(session, kernel_tracer_fd);
1946 if (ret < 0) {
1947 ret = LTTCOMM_KERN_SESS_FAIL;
1948 goto error;
1949 }
1950
1951 /* Set kernel consumer socket fd */
1952 if (kconsumer_data.cmd_sock) {
1953 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1954 }
1955
1956 ret = run_as_mkdir_recursive(session->kernel_session->trace_path,
1957 S_IRWXU | S_IRWXG, session->uid, session->gid);
1958 if (ret < 0) {
1959 if (ret != -EEXIST) {
1960 ERR("Trace directory creation error");
1961 goto error;
1962 }
1963 }
1964 session->kernel_session->uid = session->uid;
1965 session->kernel_session->gid = session->gid;
1966
1967 error:
1968 return ret;
1969 }
1970
1971 /*
1972 * Check if the UID or GID match the session. Root user has access to all
1973 * sessions.
1974 */
1975 static int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid)
1976 {
1977 if (uid != session->uid && gid != session->gid && uid != 0) {
1978 return 0;
1979 } else {
1980 return 1;
1981 }
1982 }
1983
1984 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
1985 {
1986 unsigned int i = 0;
1987 struct ltt_session *session;
1988
1989 DBG("Counting number of available session for UID %d GID %d",
1990 uid, gid);
1991 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1992 /*
1993 * Only list the sessions the user can control.
1994 */
1995 if (!session_access_ok(session, uid, gid)) {
1996 continue;
1997 }
1998 i++;
1999 }
2000 return i;
2001 }
2002
2003 /*
2004 * Using the session list, filled a lttng_session array to send back to the
2005 * client for session listing.
2006 *
2007 * The session list lock MUST be acquired before calling this function. Use
2008 * session_lock_list() and session_unlock_list().
2009 */
2010 static void list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2011 gid_t gid)
2012 {
2013 unsigned int i = 0;
2014 struct ltt_session *session;
2015
2016 DBG("Getting all available session for UID %d GID %d",
2017 uid, gid);
2018 /*
2019 * Iterate over session list and append data after the control struct in
2020 * the buffer.
2021 */
2022 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2023 /*
2024 * Only list the sessions the user can control.
2025 */
2026 if (!session_access_ok(session, uid, gid)) {
2027 continue;
2028 }
2029 strncpy(sessions[i].path, session->path, PATH_MAX);
2030 sessions[i].path[PATH_MAX - 1] = '\0';
2031 strncpy(sessions[i].name, session->name, NAME_MAX);
2032 sessions[i].name[NAME_MAX - 1] = '\0';
2033 sessions[i].enabled = session->enabled;
2034 i++;
2035 }
2036 }
2037
2038 /*
2039 * Fill lttng_channel array of all channels.
2040 */
2041 static void list_lttng_channels(int domain, struct ltt_session *session,
2042 struct lttng_channel *channels)
2043 {
2044 int i = 0;
2045 struct ltt_kernel_channel *kchan;
2046
2047 DBG("Listing channels for session %s", session->name);
2048
2049 switch (domain) {
2050 case LTTNG_DOMAIN_KERNEL:
2051 /* Kernel channels */
2052 if (session->kernel_session != NULL) {
2053 cds_list_for_each_entry(kchan,
2054 &session->kernel_session->channel_list.head, list) {
2055 /* Copy lttng_channel struct to array */
2056 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2057 channels[i].enabled = kchan->enabled;
2058 i++;
2059 }
2060 }
2061 break;
2062 case LTTNG_DOMAIN_UST:
2063 {
2064 struct lttng_ht_iter iter;
2065 struct ltt_ust_channel *uchan;
2066
2067 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
2068 &iter.iter, uchan, node.node) {
2069 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2070 channels[i].attr.overwrite = uchan->attr.overwrite;
2071 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2072 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2073 channels[i].attr.switch_timer_interval =
2074 uchan->attr.switch_timer_interval;
2075 channels[i].attr.read_timer_interval =
2076 uchan->attr.read_timer_interval;
2077 channels[i].enabled = uchan->enabled;
2078 switch (uchan->attr.output) {
2079 case LTTNG_UST_MMAP:
2080 default:
2081 channels[i].attr.output = LTTNG_EVENT_MMAP;
2082 break;
2083 }
2084 i++;
2085 }
2086 break;
2087 }
2088 default:
2089 break;
2090 }
2091 }
2092
2093 /*
2094 * Create a list of ust global domain events.
2095 */
2096 static int list_lttng_ust_global_events(char *channel_name,
2097 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2098 {
2099 int i = 0, ret = 0;
2100 unsigned int nb_event = 0;
2101 struct lttng_ht_iter iter;
2102 struct lttng_ht_node_str *node;
2103 struct ltt_ust_channel *uchan;
2104 struct ltt_ust_event *uevent;
2105 struct lttng_event *tmp;
2106
2107 DBG("Listing UST global events for channel %s", channel_name);
2108
2109 rcu_read_lock();
2110
2111 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2112 node = lttng_ht_iter_get_node_str(&iter);
2113 if (node == NULL) {
2114 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2115 goto error;
2116 }
2117
2118 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2119
2120 nb_event += lttng_ht_get_count(uchan->events);
2121
2122 if (nb_event == 0) {
2123 ret = nb_event;
2124 goto error;
2125 }
2126
2127 DBG3("Listing UST global %d events", nb_event);
2128
2129 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2130 if (tmp == NULL) {
2131 ret = -LTTCOMM_FATAL;
2132 goto error;
2133 }
2134
2135 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2136 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2137 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2138 tmp[i].enabled = uevent->enabled;
2139 switch (uevent->attr.instrumentation) {
2140 case LTTNG_UST_TRACEPOINT:
2141 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2142 break;
2143 case LTTNG_UST_PROBE:
2144 tmp[i].type = LTTNG_EVENT_PROBE;
2145 break;
2146 case LTTNG_UST_FUNCTION:
2147 tmp[i].type = LTTNG_EVENT_FUNCTION;
2148 break;
2149 case LTTNG_UST_TRACEPOINT_LOGLEVEL:
2150 tmp[i].type = LTTNG_EVENT_TRACEPOINT_LOGLEVEL;
2151 break;
2152 }
2153 i++;
2154 }
2155
2156 ret = nb_event;
2157 *events = tmp;
2158
2159 error:
2160 rcu_read_unlock();
2161 return ret;
2162 }
2163
2164 /*
2165 * Fill lttng_event array of all kernel events in the channel.
2166 */
2167 static int list_lttng_kernel_events(char *channel_name,
2168 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2169 {
2170 int i = 0, ret;
2171 unsigned int nb_event;
2172 struct ltt_kernel_event *event;
2173 struct ltt_kernel_channel *kchan;
2174
2175 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2176 if (kchan == NULL) {
2177 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2178 goto error;
2179 }
2180
2181 nb_event = kchan->event_count;
2182
2183 DBG("Listing events for channel %s", kchan->channel->name);
2184
2185 if (nb_event == 0) {
2186 ret = nb_event;
2187 goto error;
2188 }
2189
2190 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2191 if (*events == NULL) {
2192 ret = LTTCOMM_FATAL;
2193 goto error;
2194 }
2195
2196 /* Kernel channels */
2197 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2198 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2199 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2200 (*events)[i].enabled = event->enabled;
2201 switch (event->event->instrumentation) {
2202 case LTTNG_KERNEL_TRACEPOINT:
2203 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2204 break;
2205 case LTTNG_KERNEL_KPROBE:
2206 case LTTNG_KERNEL_KRETPROBE:
2207 (*events)[i].type = LTTNG_EVENT_PROBE;
2208 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2209 sizeof(struct lttng_kernel_kprobe));
2210 break;
2211 case LTTNG_KERNEL_FUNCTION:
2212 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2213 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2214 sizeof(struct lttng_kernel_function));
2215 break;
2216 case LTTNG_KERNEL_NOOP:
2217 (*events)[i].type = LTTNG_EVENT_NOOP;
2218 break;
2219 case LTTNG_KERNEL_SYSCALL:
2220 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2221 break;
2222 case LTTNG_KERNEL_ALL:
2223 assert(0);
2224 break;
2225 }
2226 i++;
2227 }
2228
2229 return nb_event;
2230
2231 error:
2232 return ret;
2233 }
2234
2235 /*
2236 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2237 */
2238 static int cmd_disable_channel(struct ltt_session *session,
2239 int domain, char *channel_name)
2240 {
2241 int ret;
2242 struct ltt_ust_session *usess;
2243
2244 usess = session->ust_session;
2245
2246 switch (domain) {
2247 case LTTNG_DOMAIN_KERNEL:
2248 {
2249 ret = channel_kernel_disable(session->kernel_session,
2250 channel_name);
2251 if (ret != LTTCOMM_OK) {
2252 goto error;
2253 }
2254
2255 kernel_wait_quiescent(kernel_tracer_fd);
2256 break;
2257 }
2258 case LTTNG_DOMAIN_UST:
2259 {
2260 struct ltt_ust_channel *uchan;
2261 struct lttng_ht *chan_ht;
2262
2263 chan_ht = usess->domain_global.channels;
2264
2265 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2266 if (uchan == NULL) {
2267 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2268 goto error;
2269 }
2270
2271 ret = channel_ust_disable(usess, domain, uchan);
2272 if (ret != LTTCOMM_OK) {
2273 goto error;
2274 }
2275 break;
2276 }
2277 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2278 case LTTNG_DOMAIN_UST_EXEC_NAME:
2279 case LTTNG_DOMAIN_UST_PID:
2280 ret = LTTCOMM_NOT_IMPLEMENTED;
2281 goto error;
2282 default:
2283 ret = LTTCOMM_UNKNOWN_DOMAIN;
2284 goto error;
2285 }
2286
2287 ret = LTTCOMM_OK;
2288
2289 error:
2290 return ret;
2291 }
2292
2293 /*
2294 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2295 */
2296 static int cmd_enable_channel(struct ltt_session *session,
2297 int domain, struct lttng_channel *attr)
2298 {
2299 int ret;
2300 struct ltt_ust_session *usess = session->ust_session;
2301 struct lttng_ht *chan_ht;
2302
2303 DBG("Enabling channel %s for session %s", attr->name, session->name);
2304
2305 switch (domain) {
2306 case LTTNG_DOMAIN_KERNEL:
2307 {
2308 struct ltt_kernel_channel *kchan;
2309
2310 kchan = trace_kernel_get_channel_by_name(attr->name,
2311 session->kernel_session);
2312 if (kchan == NULL) {
2313 ret = channel_kernel_create(session->kernel_session,
2314 attr, kernel_poll_pipe[1]);
2315 } else {
2316 ret = channel_kernel_enable(session->kernel_session, kchan);
2317 }
2318
2319 if (ret != LTTCOMM_OK) {
2320 goto error;
2321 }
2322
2323 kernel_wait_quiescent(kernel_tracer_fd);
2324 break;
2325 }
2326 case LTTNG_DOMAIN_UST:
2327 {
2328 struct ltt_ust_channel *uchan;
2329
2330 chan_ht = usess->domain_global.channels;
2331
2332 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2333 if (uchan == NULL) {
2334 ret = channel_ust_create(usess, domain, attr);
2335 } else {
2336 ret = channel_ust_enable(usess, domain, uchan);
2337 }
2338 break;
2339 }
2340 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2341 case LTTNG_DOMAIN_UST_EXEC_NAME:
2342 case LTTNG_DOMAIN_UST_PID:
2343 ret = LTTCOMM_NOT_IMPLEMENTED;
2344 goto error;
2345 default:
2346 ret = LTTCOMM_UNKNOWN_DOMAIN;
2347 goto error;
2348 }
2349
2350 error:
2351 return ret;
2352 }
2353
2354 /*
2355 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2356 */
2357 static int cmd_disable_event(struct ltt_session *session, int domain,
2358 char *channel_name, char *event_name)
2359 {
2360 int ret;
2361
2362 switch (domain) {
2363 case LTTNG_DOMAIN_KERNEL:
2364 {
2365 struct ltt_kernel_channel *kchan;
2366 struct ltt_kernel_session *ksess;
2367
2368 ksess = session->kernel_session;
2369
2370 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2371 if (kchan == NULL) {
2372 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2373 goto error;
2374 }
2375
2376 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2377 if (ret != LTTCOMM_OK) {
2378 goto error;
2379 }
2380
2381 kernel_wait_quiescent(kernel_tracer_fd);
2382 break;
2383 }
2384 case LTTNG_DOMAIN_UST:
2385 {
2386 struct ltt_ust_channel *uchan;
2387 struct ltt_ust_session *usess;
2388
2389 usess = session->ust_session;
2390
2391 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2392 channel_name);
2393 if (uchan == NULL) {
2394 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2395 goto error;
2396 }
2397
2398 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2399 if (ret != LTTCOMM_OK) {
2400 goto error;
2401 }
2402
2403 DBG3("Disable UST event %s in channel %s completed", event_name,
2404 channel_name);
2405 break;
2406 }
2407 case LTTNG_DOMAIN_UST_EXEC_NAME:
2408 case LTTNG_DOMAIN_UST_PID:
2409 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2410 default:
2411 ret = LTTCOMM_NOT_IMPLEMENTED;
2412 goto error;
2413 }
2414
2415 ret = LTTCOMM_OK;
2416
2417 error:
2418 return ret;
2419 }
2420
2421 /*
2422 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2423 */
2424 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2425 char *channel_name)
2426 {
2427 int ret;
2428
2429 switch (domain) {
2430 case LTTNG_DOMAIN_KERNEL:
2431 {
2432 struct ltt_kernel_session *ksess;
2433 struct ltt_kernel_channel *kchan;
2434
2435 ksess = session->kernel_session;
2436
2437 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2438 if (kchan == NULL) {
2439 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2440 goto error;
2441 }
2442
2443 ret = event_kernel_disable_all(ksess, kchan);
2444 if (ret != LTTCOMM_OK) {
2445 goto error;
2446 }
2447
2448 kernel_wait_quiescent(kernel_tracer_fd);
2449 break;
2450 }
2451 case LTTNG_DOMAIN_UST:
2452 {
2453 struct ltt_ust_session *usess;
2454 struct ltt_ust_channel *uchan;
2455
2456 usess = session->ust_session;
2457
2458 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2459 channel_name);
2460 if (uchan == NULL) {
2461 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2462 goto error;
2463 }
2464
2465 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2466 if (ret != 0) {
2467 goto error;
2468 }
2469
2470 DBG3("Disable all UST events in channel %s completed", channel_name);
2471
2472 break;
2473 }
2474 case LTTNG_DOMAIN_UST_EXEC_NAME:
2475 case LTTNG_DOMAIN_UST_PID:
2476 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2477 default:
2478 ret = LTTCOMM_NOT_IMPLEMENTED;
2479 goto error;
2480 }
2481
2482 ret = LTTCOMM_OK;
2483
2484 error:
2485 return ret;
2486 }
2487
2488 /*
2489 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2490 */
2491 static int cmd_add_context(struct ltt_session *session, int domain,
2492 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2493 {
2494 int ret;
2495
2496 switch (domain) {
2497 case LTTNG_DOMAIN_KERNEL:
2498 /* Add kernel context to kernel tracer */
2499 ret = context_kernel_add(session->kernel_session, ctx,
2500 event_name, channel_name);
2501 if (ret != LTTCOMM_OK) {
2502 goto error;
2503 }
2504 break;
2505 case LTTNG_DOMAIN_UST:
2506 {
2507 struct ltt_ust_session *usess = session->ust_session;
2508
2509 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2510 if (ret != LTTCOMM_OK) {
2511 goto error;
2512 }
2513 break;
2514 }
2515 case LTTNG_DOMAIN_UST_EXEC_NAME:
2516 case LTTNG_DOMAIN_UST_PID:
2517 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2518 default:
2519 ret = LTTCOMM_NOT_IMPLEMENTED;
2520 goto error;
2521 }
2522
2523 ret = LTTCOMM_OK;
2524
2525 error:
2526 return ret;
2527 }
2528
2529 /*
2530 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2531 *
2532 * TODO: currently, both events and loglevels are kept within the same
2533 * namespace for UST global registry/app registery, so if an event
2534 * happen to have the same name as the loglevel (very unlikely though),
2535 * and an attempt is made to enable/disable both in the same session,
2536 * the first to be created will be the only one allowed to exist.
2537 */
2538 static int cmd_enable_event(struct ltt_session *session, int domain,
2539 char *channel_name, struct lttng_event *event)
2540 {
2541 int ret;
2542 struct lttng_channel *attr;
2543 struct ltt_ust_session *usess = session->ust_session;
2544
2545 switch (domain) {
2546 case LTTNG_DOMAIN_KERNEL:
2547 {
2548 struct ltt_kernel_channel *kchan;
2549
2550 kchan = trace_kernel_get_channel_by_name(channel_name,
2551 session->kernel_session);
2552 if (kchan == NULL) {
2553 attr = channel_new_default_attr(domain);
2554 if (attr == NULL) {
2555 ret = LTTCOMM_FATAL;
2556 goto error;
2557 }
2558 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2559
2560 /* This call will notify the kernel thread */
2561 ret = channel_kernel_create(session->kernel_session,
2562 attr, kernel_poll_pipe[1]);
2563 if (ret != LTTCOMM_OK) {
2564 free(attr);
2565 goto error;
2566 }
2567 free(attr);
2568 }
2569
2570 /* Get the newly created kernel channel pointer */
2571 kchan = trace_kernel_get_channel_by_name(channel_name,
2572 session->kernel_session);
2573 if (kchan == NULL) {
2574 /* This sould not happen... */
2575 ret = LTTCOMM_FATAL;
2576 goto error;
2577 }
2578
2579 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2580 event);
2581 if (ret != LTTCOMM_OK) {
2582 goto error;
2583 }
2584
2585 kernel_wait_quiescent(kernel_tracer_fd);
2586 break;
2587 }
2588 case LTTNG_DOMAIN_UST:
2589 {
2590 struct lttng_channel *attr;
2591 struct ltt_ust_channel *uchan;
2592
2593 /* Get channel from global UST domain */
2594 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2595 channel_name);
2596 if (uchan == NULL) {
2597 /* Create default channel */
2598 attr = channel_new_default_attr(domain);
2599 if (attr == NULL) {
2600 ret = LTTCOMM_FATAL;
2601 goto error;
2602 }
2603 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2604 attr->name[NAME_MAX - 1] = '\0';
2605
2606 ret = channel_ust_create(usess, domain, attr);
2607 if (ret != LTTCOMM_OK) {
2608 free(attr);
2609 goto error;
2610 }
2611 free(attr);
2612
2613 /* Get the newly created channel reference back */
2614 uchan = trace_ust_find_channel_by_name(
2615 usess->domain_global.channels, channel_name);
2616 if (uchan == NULL) {
2617 /* Something is really wrong */
2618 ret = LTTCOMM_FATAL;
2619 goto error;
2620 }
2621 }
2622
2623 /* At this point, the session and channel exist on the tracer */
2624 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2625 if (ret != LTTCOMM_OK) {
2626 goto error;
2627 }
2628 break;
2629 }
2630 case LTTNG_DOMAIN_UST_EXEC_NAME:
2631 case LTTNG_DOMAIN_UST_PID:
2632 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2633 default:
2634 ret = LTTCOMM_NOT_IMPLEMENTED;
2635 goto error;
2636 }
2637
2638 ret = LTTCOMM_OK;
2639
2640 error:
2641 return ret;
2642 }
2643
2644 /*
2645 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2646 */
2647 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2648 char *channel_name, int event_type)
2649 {
2650 int ret;
2651 struct ltt_kernel_channel *kchan;
2652
2653 switch (domain) {
2654 case LTTNG_DOMAIN_KERNEL:
2655 kchan = trace_kernel_get_channel_by_name(channel_name,
2656 session->kernel_session);
2657 if (kchan == NULL) {
2658 /* This call will notify the kernel thread */
2659 ret = channel_kernel_create(session->kernel_session, NULL,
2660 kernel_poll_pipe[1]);
2661 if (ret != LTTCOMM_OK) {
2662 goto error;
2663 }
2664
2665 /* Get the newly created kernel channel pointer */
2666 kchan = trace_kernel_get_channel_by_name(channel_name,
2667 session->kernel_session);
2668 if (kchan == NULL) {
2669 /* This sould not happen... */
2670 ret = LTTCOMM_FATAL;
2671 goto error;
2672 }
2673
2674 }
2675
2676 switch (event_type) {
2677 case LTTNG_EVENT_SYSCALL:
2678 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2679 kchan, kernel_tracer_fd);
2680 break;
2681 case LTTNG_EVENT_TRACEPOINT:
2682 /*
2683 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2684 * events already registered to the channel.
2685 */
2686 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2687 kchan, kernel_tracer_fd);
2688 break;
2689 case LTTNG_EVENT_ALL:
2690 /* Enable syscalls and tracepoints */
2691 ret = event_kernel_enable_all(session->kernel_session,
2692 kchan, kernel_tracer_fd);
2693 break;
2694 default:
2695 ret = LTTCOMM_KERN_ENABLE_FAIL;
2696 goto error;
2697 }
2698
2699 /* Manage return value */
2700 if (ret != LTTCOMM_OK) {
2701 goto error;
2702 }
2703
2704 kernel_wait_quiescent(kernel_tracer_fd);
2705 break;
2706 case LTTNG_DOMAIN_UST:
2707 {
2708 struct lttng_channel *attr;
2709 struct ltt_ust_channel *uchan;
2710 struct ltt_ust_session *usess = session->ust_session;
2711
2712 /* Get channel from global UST domain */
2713 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2714 channel_name);
2715 if (uchan == NULL) {
2716 /* Create default channel */
2717 attr = channel_new_default_attr(domain);
2718 if (attr == NULL) {
2719 ret = LTTCOMM_FATAL;
2720 goto error;
2721 }
2722 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2723 attr->name[NAME_MAX - 1] = '\0';
2724
2725 /* Use the internal command enable channel */
2726 ret = channel_ust_create(usess, domain, attr);
2727 if (ret != LTTCOMM_OK) {
2728 free(attr);
2729 goto error;
2730 }
2731 free(attr);
2732
2733 /* Get the newly created channel reference back */
2734 uchan = trace_ust_find_channel_by_name(
2735 usess->domain_global.channels, channel_name);
2736 if (uchan == NULL) {
2737 /* Something is really wrong */
2738 ret = LTTCOMM_FATAL;
2739 goto error;
2740 }
2741 }
2742
2743 /* At this point, the session and channel exist on the tracer */
2744
2745 switch (event_type) {
2746 case LTTNG_EVENT_ALL:
2747 case LTTNG_EVENT_TRACEPOINT:
2748 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2749 if (ret != LTTCOMM_OK) {
2750 goto error;
2751 }
2752 break;
2753 default:
2754 ret = LTTCOMM_UST_ENABLE_FAIL;
2755 goto error;
2756 }
2757
2758 /* Manage return value */
2759 if (ret != LTTCOMM_OK) {
2760 goto error;
2761 }
2762
2763 break;
2764 }
2765 case LTTNG_DOMAIN_UST_EXEC_NAME:
2766 case LTTNG_DOMAIN_UST_PID:
2767 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2768 default:
2769 ret = LTTCOMM_NOT_IMPLEMENTED;
2770 goto error;
2771 }
2772
2773 ret = LTTCOMM_OK;
2774
2775 error:
2776 return ret;
2777 }
2778
2779 /*
2780 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2781 */
2782 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2783 {
2784 int ret;
2785 ssize_t nb_events = 0;
2786
2787 switch (domain) {
2788 case LTTNG_DOMAIN_KERNEL:
2789 nb_events = kernel_list_events(kernel_tracer_fd, events);
2790 if (nb_events < 0) {
2791 ret = LTTCOMM_KERN_LIST_FAIL;
2792 goto error;
2793 }
2794 break;
2795 case LTTNG_DOMAIN_UST:
2796 nb_events = ust_app_list_events(events);
2797 if (nb_events < 0) {
2798 ret = LTTCOMM_UST_LIST_FAIL;
2799 goto error;
2800 }
2801 break;
2802 default:
2803 ret = LTTCOMM_NOT_IMPLEMENTED;
2804 goto error;
2805 }
2806
2807 return nb_events;
2808
2809 error:
2810 /* Return negative value to differentiate return code */
2811 return -ret;
2812 }
2813
2814 /*
2815 * Command LTTNG_START_TRACE processed by the client thread.
2816 */
2817 static int cmd_start_trace(struct ltt_session *session)
2818 {
2819 int ret;
2820 struct ltt_kernel_session *ksession;
2821 struct ltt_ust_session *usess;
2822
2823 /* Short cut */
2824 ksession = session->kernel_session;
2825 usess = session->ust_session;
2826
2827 if (session->enabled) {
2828 ret = LTTCOMM_UST_START_FAIL;
2829 goto error;
2830 }
2831
2832 session->enabled = 1;
2833
2834 /* Kernel tracing */
2835 if (ksession != NULL) {
2836 struct ltt_kernel_channel *kchan;
2837
2838 /* Open kernel metadata */
2839 if (ksession->metadata == NULL) {
2840 ret = kernel_open_metadata(ksession, ksession->trace_path);
2841 if (ret < 0) {
2842 ret = LTTCOMM_KERN_META_FAIL;
2843 goto error;
2844 }
2845 }
2846
2847 /* Open kernel metadata stream */
2848 if (ksession->metadata_stream_fd == 0) {
2849 ret = kernel_open_metadata_stream(ksession);
2850 if (ret < 0) {
2851 ERR("Kernel create metadata stream failed");
2852 ret = LTTCOMM_KERN_STREAM_FAIL;
2853 goto error;
2854 }
2855 }
2856
2857 /* For each channel */
2858 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2859 if (kchan->stream_count == 0) {
2860 ret = kernel_open_channel_stream(kchan);
2861 if (ret < 0) {
2862 ret = LTTCOMM_KERN_STREAM_FAIL;
2863 goto error;
2864 }
2865 /* Update the stream global counter */
2866 ksession->stream_count_global += ret;
2867 }
2868 }
2869
2870 /* Setup kernel consumer socket and send fds to it */
2871 ret = init_kernel_tracing(ksession);
2872 if (ret < 0) {
2873 ret = LTTCOMM_KERN_START_FAIL;
2874 goto error;
2875 }
2876
2877 /* This start the kernel tracing */
2878 ret = kernel_start_session(ksession);
2879 if (ret < 0) {
2880 ret = LTTCOMM_KERN_START_FAIL;
2881 goto error;
2882 }
2883
2884 /* Quiescent wait after starting trace */
2885 kernel_wait_quiescent(kernel_tracer_fd);
2886 }
2887
2888 /* Flag session that trace should start automatically */
2889 if (usess) {
2890 usess->start_trace = 1;
2891
2892 ret = ust_app_start_trace_all(usess);
2893 if (ret < 0) {
2894 ret = LTTCOMM_UST_START_FAIL;
2895 goto error;
2896 }
2897 }
2898
2899 ret = LTTCOMM_OK;
2900
2901 error:
2902 return ret;
2903 }
2904
2905 /*
2906 * Command LTTNG_STOP_TRACE processed by the client thread.
2907 */
2908 static int cmd_stop_trace(struct ltt_session *session)
2909 {
2910 int ret;
2911 struct ltt_kernel_channel *kchan;
2912 struct ltt_kernel_session *ksession;
2913 struct ltt_ust_session *usess;
2914
2915 /* Short cut */
2916 ksession = session->kernel_session;
2917 usess = session->ust_session;
2918
2919 if (!session->enabled) {
2920 ret = LTTCOMM_UST_STOP_FAIL;
2921 goto error;
2922 }
2923
2924 session->enabled = 0;
2925
2926 /* Kernel tracer */
2927 if (ksession != NULL) {
2928 DBG("Stop kernel tracing");
2929
2930 /* Flush all buffers before stopping */
2931 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2932 if (ret < 0) {
2933 ERR("Kernel metadata flush failed");
2934 }
2935
2936 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2937 ret = kernel_flush_buffer(kchan);
2938 if (ret < 0) {
2939 ERR("Kernel flush buffer error");
2940 }
2941 }
2942
2943 ret = kernel_stop_session(ksession);
2944 if (ret < 0) {
2945 ret = LTTCOMM_KERN_STOP_FAIL;
2946 goto error;
2947 }
2948
2949 kernel_wait_quiescent(kernel_tracer_fd);
2950 }
2951
2952 if (usess) {
2953 usess->start_trace = 0;
2954
2955 ret = ust_app_stop_trace_all(usess);
2956 if (ret < 0) {
2957 ret = LTTCOMM_UST_STOP_FAIL;
2958 goto error;
2959 }
2960 }
2961
2962 ret = LTTCOMM_OK;
2963
2964 error:
2965 return ret;
2966 }
2967
2968 /*
2969 * Command LTTNG_CREATE_SESSION processed by the client thread.
2970 */
2971 static int cmd_create_session(char *name, char *path, struct ucred *creds)
2972 {
2973 int ret;
2974
2975 ret = session_create(name, path, creds->uid, creds->gid);
2976 if (ret != LTTCOMM_OK) {
2977 goto error;
2978 }
2979
2980 ret = LTTCOMM_OK;
2981
2982 error:
2983 return ret;
2984 }
2985
2986 /*
2987 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2988 */
2989 static int cmd_destroy_session(struct ltt_session *session, char *name)
2990 {
2991 int ret;
2992
2993 /* Clean kernel session teardown */
2994 teardown_kernel_session(session);
2995 /* UST session teardown */
2996 teardown_ust_session(session);
2997
2998 /*
2999 * Must notify the kernel thread here to update it's poll setin order
3000 * to remove the channel(s)' fd just destroyed.
3001 */
3002 ret = notify_thread_pipe(kernel_poll_pipe[1]);
3003 if (ret < 0) {
3004 perror("write kernel poll pipe");
3005 }
3006
3007 ret = session_destroy(session);
3008
3009 return ret;
3010 }
3011
3012 /*
3013 * Command LTTNG_CALIBRATE processed by the client thread.
3014 */
3015 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3016 {
3017 int ret;
3018
3019 switch (domain) {
3020 case LTTNG_DOMAIN_KERNEL:
3021 {
3022 struct lttng_kernel_calibrate kcalibrate;
3023
3024 kcalibrate.type = calibrate->type;
3025 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3026 if (ret < 0) {
3027 ret = LTTCOMM_KERN_ENABLE_FAIL;
3028 goto error;
3029 }
3030 break;
3031 }
3032 default:
3033 /* TODO: Userspace tracing */
3034 ret = LTTCOMM_NOT_IMPLEMENTED;
3035 goto error;
3036 }
3037
3038 ret = LTTCOMM_OK;
3039
3040 error:
3041 return ret;
3042 }
3043
3044 /*
3045 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3046 */
3047 static int cmd_register_consumer(struct ltt_session *session, int domain,
3048 char *sock_path)
3049 {
3050 int ret, sock;
3051
3052 switch (domain) {
3053 case LTTNG_DOMAIN_KERNEL:
3054 /* Can't register a consumer if there is already one */
3055 if (session->kernel_session->consumer_fds_sent != 0) {
3056 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3057 goto error;
3058 }
3059
3060 sock = lttcomm_connect_unix_sock(sock_path);
3061 if (sock < 0) {
3062 ret = LTTCOMM_CONNECT_FAIL;
3063 goto error;
3064 }
3065
3066 session->kernel_session->consumer_fd = sock;
3067 break;
3068 default:
3069 /* TODO: Userspace tracing */
3070 ret = LTTCOMM_NOT_IMPLEMENTED;
3071 goto error;
3072 }
3073
3074 ret = LTTCOMM_OK;
3075
3076 error:
3077 return ret;
3078 }
3079
3080 /*
3081 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3082 */
3083 static ssize_t cmd_list_domains(struct ltt_session *session,
3084 struct lttng_domain **domains)
3085 {
3086 int ret, index = 0;
3087 ssize_t nb_dom = 0;
3088
3089 if (session->kernel_session != NULL) {
3090 DBG3("Listing domains found kernel domain");
3091 nb_dom++;
3092 }
3093
3094 if (session->ust_session != NULL) {
3095 DBG3("Listing domains found UST global domain");
3096 nb_dom++;
3097 }
3098
3099 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3100 if (*domains == NULL) {
3101 ret = -LTTCOMM_FATAL;
3102 goto error;
3103 }
3104
3105 if (session->kernel_session != NULL) {
3106 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3107 index++;
3108 }
3109
3110 if (session->ust_session != NULL) {
3111 (*domains)[index].type = LTTNG_DOMAIN_UST;
3112 index++;
3113 }
3114
3115 return nb_dom;
3116
3117 error:
3118 return ret;
3119 }
3120
3121 /*
3122 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3123 */
3124 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3125 struct lttng_channel **channels)
3126 {
3127 int ret;
3128 ssize_t nb_chan = 0;
3129
3130 switch (domain) {
3131 case LTTNG_DOMAIN_KERNEL:
3132 if (session->kernel_session != NULL) {
3133 nb_chan = session->kernel_session->channel_count;
3134 }
3135 DBG3("Number of kernel channels %zd", nb_chan);
3136 break;
3137 case LTTNG_DOMAIN_UST:
3138 if (session->ust_session != NULL) {
3139 nb_chan = lttng_ht_get_count(
3140 session->ust_session->domain_global.channels);
3141 }
3142 DBG3("Number of UST global channels %zd", nb_chan);
3143 break;
3144 default:
3145 *channels = NULL;
3146 ret = -LTTCOMM_NOT_IMPLEMENTED;
3147 goto error;
3148 }
3149
3150 if (nb_chan > 0) {
3151 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3152 if (*channels == NULL) {
3153 ret = -LTTCOMM_FATAL;
3154 goto error;
3155 }
3156
3157 list_lttng_channels(domain, session, *channels);
3158 } else {
3159 *channels = NULL;
3160 }
3161
3162 return nb_chan;
3163
3164 error:
3165 return ret;
3166 }
3167
3168 /*
3169 * Command LTTNG_LIST_EVENTS processed by the client thread.
3170 */
3171 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3172 char *channel_name, struct lttng_event **events)
3173 {
3174 int ret = 0;
3175 ssize_t nb_event = 0;
3176
3177 switch (domain) {
3178 case LTTNG_DOMAIN_KERNEL:
3179 if (session->kernel_session != NULL) {
3180 nb_event = list_lttng_kernel_events(channel_name,
3181 session->kernel_session, events);
3182 }
3183 break;
3184 case LTTNG_DOMAIN_UST:
3185 {
3186 if (session->ust_session != NULL) {
3187 nb_event = list_lttng_ust_global_events(channel_name,
3188 &session->ust_session->domain_global, events);
3189 }
3190 break;
3191 }
3192 default:
3193 ret = -LTTCOMM_NOT_IMPLEMENTED;
3194 goto error;
3195 }
3196
3197 ret = nb_event;
3198
3199 error:
3200 return ret;
3201 }
3202
3203 /*
3204 * Process the command requested by the lttng client within the command
3205 * context structure. This function make sure that the return structure (llm)
3206 * is set and ready for transmission before returning.
3207 *
3208 * Return any error encountered or 0 for success.
3209 */
3210 static int process_client_msg(struct command_ctx *cmd_ctx)
3211 {
3212 int ret = LTTCOMM_OK;
3213 int need_tracing_session = 1;
3214
3215 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3216
3217 if (opt_no_kernel && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
3218 ret = LTTCOMM_KERN_NA;
3219 goto error;
3220 }
3221
3222 /*
3223 * Check for command that don't needs to allocate a returned payload. We do
3224 * this here so we don't have to make the call for no payload at each
3225 * command.
3226 */
3227 switch(cmd_ctx->lsm->cmd_type) {
3228 case LTTNG_LIST_SESSIONS:
3229 case LTTNG_LIST_TRACEPOINTS:
3230 case LTTNG_LIST_DOMAINS:
3231 case LTTNG_LIST_CHANNELS:
3232 case LTTNG_LIST_EVENTS:
3233 break;
3234 default:
3235 /* Setup lttng message with no payload */
3236 ret = setup_lttng_msg(cmd_ctx, 0);
3237 if (ret < 0) {
3238 /* This label does not try to unlock the session */
3239 goto init_setup_error;
3240 }
3241 }
3242
3243 /* Commands that DO NOT need a session. */
3244 switch (cmd_ctx->lsm->cmd_type) {
3245 case LTTNG_CALIBRATE:
3246 case LTTNG_CREATE_SESSION:
3247 case LTTNG_LIST_SESSIONS:
3248 case LTTNG_LIST_TRACEPOINTS:
3249 need_tracing_session = 0;
3250 break;
3251 default:
3252 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3253 session_lock_list();
3254 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3255 session_unlock_list();
3256 if (cmd_ctx->session == NULL) {
3257 if (cmd_ctx->lsm->session.name != NULL) {
3258 ret = LTTCOMM_SESS_NOT_FOUND;
3259 } else {
3260 /* If no session name specified */
3261 ret = LTTCOMM_SELECT_SESS;
3262 }
3263 goto error;
3264 } else {
3265 /* Acquire lock for the session */
3266 session_lock(cmd_ctx->session);
3267 }
3268 break;
3269 }
3270
3271 /*
3272 * Check domain type for specific "pre-action".
3273 */
3274 switch (cmd_ctx->lsm->domain.type) {
3275 case LTTNG_DOMAIN_KERNEL:
3276 if (!is_root) {
3277 ret = LTTCOMM_KERN_NA;
3278 goto error;
3279 }
3280
3281 /* Kernel tracer check */
3282 if (kernel_tracer_fd == 0) {
3283 /* Basically, load kernel tracer modules */
3284 init_kernel_tracer();
3285 if (kernel_tracer_fd == 0) {
3286 ret = LTTCOMM_KERN_NA;
3287 goto error;
3288 }
3289 }
3290
3291 /* Need a session for kernel command */
3292 if (need_tracing_session) {
3293 if (cmd_ctx->session->kernel_session == NULL) {
3294 ret = create_kernel_session(cmd_ctx->session);
3295 if (ret < 0) {
3296 ret = LTTCOMM_KERN_SESS_FAIL;
3297 goto error;
3298 }
3299 }
3300
3301 /* Start the kernel consumer daemon */
3302 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3303 if (kconsumer_data.pid == 0 &&
3304 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3305 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3306 ret = start_consumerd(&kconsumer_data);
3307 if (ret < 0) {
3308 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3309 goto error;
3310 }
3311 } else {
3312 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3313 }
3314 }
3315 break;
3316 case LTTNG_DOMAIN_UST:
3317 {
3318 if (need_tracing_session) {
3319 if (cmd_ctx->session->ust_session == NULL) {
3320 ret = create_ust_session(cmd_ctx->session,
3321 &cmd_ctx->lsm->domain);
3322 if (ret != LTTCOMM_OK) {
3323 goto error;
3324 }
3325 }
3326 /* Start the UST consumer daemons */
3327 /* 64-bit */
3328 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3329 if (consumerd64_bin[0] != '\0' &&
3330 ustconsumer64_data.pid == 0 &&
3331 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3332 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3333 ret = start_consumerd(&ustconsumer64_data);
3334 if (ret < 0) {
3335 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3336 ust_consumerd64_fd = -EINVAL;
3337 goto error;
3338 }
3339
3340 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3341 } else {
3342 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3343 }
3344 /* 32-bit */
3345 if (consumerd32_bin[0] != '\0' &&
3346 ustconsumer32_data.pid == 0 &&
3347 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3348 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3349 ret = start_consumerd(&ustconsumer32_data);
3350 if (ret < 0) {
3351 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3352 ust_consumerd32_fd = -EINVAL;
3353 goto error;
3354 }
3355 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3356 } else {
3357 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3358 }
3359 }
3360 break;
3361 }
3362 default:
3363 break;
3364 }
3365
3366 /*
3367 * Check that the UID or GID match that of the tracing session.
3368 * The root user can interact with all sessions.
3369 */
3370 if (need_tracing_session) {
3371 if (!session_access_ok(cmd_ctx->session,
3372 cmd_ctx->creds.uid, cmd_ctx->creds.gid)) {
3373 ret = LTTCOMM_EPERM;
3374 goto error;
3375 }
3376 }
3377
3378 /* Process by command type */
3379 switch (cmd_ctx->lsm->cmd_type) {
3380 case LTTNG_ADD_CONTEXT:
3381 {
3382 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3383 cmd_ctx->lsm->u.context.channel_name,
3384 cmd_ctx->lsm->u.context.event_name,
3385 &cmd_ctx->lsm->u.context.ctx);
3386 break;
3387 }
3388 case LTTNG_DISABLE_CHANNEL:
3389 {
3390 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3391 cmd_ctx->lsm->u.disable.channel_name);
3392 break;
3393 }
3394 case LTTNG_DISABLE_EVENT:
3395 {
3396 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3397 cmd_ctx->lsm->u.disable.channel_name,
3398 cmd_ctx->lsm->u.disable.name);
3399 ret = LTTCOMM_OK;
3400 break;
3401 }
3402 case LTTNG_DISABLE_ALL_EVENT:
3403 {
3404 DBG("Disabling all events");
3405
3406 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3407 cmd_ctx->lsm->u.disable.channel_name);
3408 break;
3409 }
3410 case LTTNG_ENABLE_CHANNEL:
3411 {
3412 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3413 &cmd_ctx->lsm->u.channel.chan);
3414 break;
3415 }
3416 case LTTNG_ENABLE_EVENT:
3417 {
3418 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3419 cmd_ctx->lsm->u.enable.channel_name,
3420 &cmd_ctx->lsm->u.enable.event);
3421 break;
3422 }
3423 case LTTNG_ENABLE_ALL_EVENT:
3424 {
3425 DBG("Enabling all events");
3426
3427 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3428 cmd_ctx->lsm->u.enable.channel_name,
3429 cmd_ctx->lsm->u.enable.event.type);
3430 break;
3431 }
3432 case LTTNG_LIST_TRACEPOINTS:
3433 {
3434 struct lttng_event *events;
3435 ssize_t nb_events;
3436
3437 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3438 if (nb_events < 0) {
3439 ret = -nb_events;
3440 goto error;
3441 }
3442
3443 /*
3444 * Setup lttng message with payload size set to the event list size in
3445 * bytes and then copy list into the llm payload.
3446 */
3447 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3448 if (ret < 0) {
3449 free(events);
3450 goto setup_error;
3451 }
3452
3453 /* Copy event list into message payload */
3454 memcpy(cmd_ctx->llm->payload, events,
3455 sizeof(struct lttng_event) * nb_events);
3456
3457 free(events);
3458
3459 ret = LTTCOMM_OK;
3460 break;
3461 }
3462 case LTTNG_START_TRACE:
3463 {
3464 ret = cmd_start_trace(cmd_ctx->session);
3465 break;
3466 }
3467 case LTTNG_STOP_TRACE:
3468 {
3469 ret = cmd_stop_trace(cmd_ctx->session);
3470 break;
3471 }
3472 case LTTNG_CREATE_SESSION:
3473 {
3474 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3475 cmd_ctx->lsm->session.path, &cmd_ctx->creds);
3476 break;
3477 }
3478 case LTTNG_DESTROY_SESSION:
3479 {
3480 ret = cmd_destroy_session(cmd_ctx->session,
3481 cmd_ctx->lsm->session.name);
3482 break;
3483 }
3484 case LTTNG_LIST_DOMAINS:
3485 {
3486 ssize_t nb_dom;
3487 struct lttng_domain *domains;
3488
3489 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3490 if (nb_dom < 0) {
3491 ret = -nb_dom;
3492 goto error;
3493 }
3494
3495 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3496 if (ret < 0) {
3497 goto setup_error;
3498 }
3499
3500 /* Copy event list into message payload */
3501 memcpy(cmd_ctx->llm->payload, domains,
3502 nb_dom * sizeof(struct lttng_domain));
3503
3504 free(domains);
3505
3506 ret = LTTCOMM_OK;
3507 break;
3508 }
3509 case LTTNG_LIST_CHANNELS:
3510 {
3511 size_t nb_chan;
3512 struct lttng_channel *channels;
3513
3514 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
3515 cmd_ctx->session, &channels);
3516 if (nb_chan < 0) {
3517 ret = -nb_chan;
3518 goto error;
3519 }
3520
3521 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3522 if (ret < 0) {
3523 goto setup_error;
3524 }
3525
3526 /* Copy event list into message payload */
3527 memcpy(cmd_ctx->llm->payload, channels,
3528 nb_chan * sizeof(struct lttng_channel));
3529
3530 free(channels);
3531
3532 ret = LTTCOMM_OK;
3533 break;
3534 }
3535 case LTTNG_LIST_EVENTS:
3536 {
3537 ssize_t nb_event;
3538 struct lttng_event *events = NULL;
3539
3540 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
3541 cmd_ctx->lsm->u.list.channel_name, &events);
3542 if (nb_event < 0) {
3543 ret = -nb_event;
3544 goto error;
3545 }
3546
3547 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3548 if (ret < 0) {
3549 goto setup_error;
3550 }
3551
3552 /* Copy event list into message payload */
3553 memcpy(cmd_ctx->llm->payload, events,
3554 nb_event * sizeof(struct lttng_event));
3555
3556 free(events);
3557
3558 ret = LTTCOMM_OK;
3559 break;
3560 }
3561 case LTTNG_LIST_SESSIONS:
3562 {
3563 unsigned int nr_sessions;
3564
3565 session_lock_list();
3566 nr_sessions = lttng_sessions_count(cmd_ctx->creds.uid, cmd_ctx->creds.gid);
3567 if (nr_sessions == 0) {
3568 ret = LTTCOMM_NO_SESSION;
3569 session_unlock_list();
3570 goto error;
3571 }
3572 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * nr_sessions);
3573 if (ret < 0) {
3574 session_unlock_list();
3575 goto setup_error;
3576 }
3577
3578 /* Filled the session array */
3579 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload),
3580 cmd_ctx->creds.uid, cmd_ctx->creds.gid);
3581
3582 session_unlock_list();
3583
3584 ret = LTTCOMM_OK;
3585 break;
3586 }
3587 case LTTNG_CALIBRATE:
3588 {
3589 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3590 &cmd_ctx->lsm->u.calibrate);
3591 break;
3592 }
3593 case LTTNG_REGISTER_CONSUMER:
3594 {
3595 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3596 cmd_ctx->lsm->u.reg.path);
3597 break;
3598 }
3599 default:
3600 ret = LTTCOMM_UND;
3601 break;
3602 }
3603
3604 error:
3605 if (cmd_ctx->llm == NULL) {
3606 DBG("Missing llm structure. Allocating one.");
3607 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3608 goto setup_error;
3609 }
3610 }
3611 /* Set return code */
3612 cmd_ctx->llm->ret_code = ret;
3613 setup_error:
3614 if (cmd_ctx->session) {
3615 session_unlock(cmd_ctx->session);
3616 }
3617 init_setup_error:
3618 return ret;
3619 }
3620
3621 /*
3622 * This thread manage all clients request using the unix client socket for
3623 * communication.
3624 */
3625 static void *thread_manage_clients(void *data)
3626 {
3627 int sock = 0, ret, i, pollfd;
3628 uint32_t revents, nb_fd;
3629 struct command_ctx *cmd_ctx = NULL;
3630 struct lttng_poll_event events;
3631
3632 DBG("[thread] Manage client started");
3633
3634 rcu_register_thread();
3635
3636 ret = lttcomm_listen_unix_sock(client_sock);
3637 if (ret < 0) {
3638 goto error;
3639 }
3640
3641 /*
3642 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3643 * more will be added to this poll set.
3644 */
3645 ret = create_thread_poll_set(&events, 2);
3646 if (ret < 0) {
3647 goto error;
3648 }
3649
3650 /* Add the application registration socket */
3651 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3652 if (ret < 0) {
3653 goto error;
3654 }
3655
3656 /*
3657 * Notify parent pid that we are ready to accept command for client side.
3658 */
3659 if (opt_sig_parent) {
3660 kill(ppid, SIGCHLD);
3661 }
3662
3663 while (1) {
3664 DBG("Accepting client command ...");
3665
3666 nb_fd = LTTNG_POLL_GETNB(&events);
3667
3668 /* Inifinite blocking call, waiting for transmission */
3669 ret = lttng_poll_wait(&events, -1);
3670 if (ret < 0) {
3671 goto error;
3672 }
3673
3674 for (i = 0; i < nb_fd; i++) {
3675 /* Fetch once the poll data */
3676 revents = LTTNG_POLL_GETEV(&events, i);
3677 pollfd = LTTNG_POLL_GETFD(&events, i);
3678
3679 /* Thread quit pipe has been closed. Killing thread. */
3680 ret = check_thread_quit_pipe(pollfd, revents);
3681 if (ret) {
3682 goto error;
3683 }
3684
3685 /* Event on the registration socket */
3686 if (pollfd == client_sock) {
3687 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3688 ERR("Client socket poll error");
3689 goto error;
3690 }
3691 }
3692 }
3693
3694 DBG("Wait for client response");
3695
3696 sock = lttcomm_accept_unix_sock(client_sock);
3697 if (sock < 0) {
3698 goto error;
3699 }
3700
3701 /* Set socket option for credentials retrieval */
3702 ret = lttcomm_setsockopt_creds_unix_sock(sock);
3703 if (ret < 0) {
3704 goto error;
3705 }
3706
3707 /* Allocate context command to process the client request */
3708 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3709 if (cmd_ctx == NULL) {
3710 perror("zmalloc cmd_ctx");
3711 goto error;
3712 }
3713
3714 /* Allocate data buffer for reception */
3715 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3716 if (cmd_ctx->lsm == NULL) {
3717 perror("zmalloc cmd_ctx->lsm");
3718 goto error;
3719 }
3720
3721 cmd_ctx->llm = NULL;
3722 cmd_ctx->session = NULL;
3723
3724 /*
3725 * Data is received from the lttng client. The struct
3726 * lttcomm_session_msg (lsm) contains the command and data request of
3727 * the client.
3728 */
3729 DBG("Receiving data from client ...");
3730 ret = lttcomm_recv_creds_unix_sock(sock, cmd_ctx->lsm,
3731 sizeof(struct lttcomm_session_msg), &cmd_ctx->creds);
3732 if (ret <= 0) {
3733 DBG("Nothing recv() from client... continuing");
3734 close(sock);
3735 free(cmd_ctx);
3736 continue;
3737 }
3738
3739 // TODO: Validate cmd_ctx including sanity check for
3740 // security purpose.
3741
3742 rcu_thread_online();
3743 /*
3744 * This function dispatch the work to the kernel or userspace tracer
3745 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3746 * informations for the client. The command context struct contains
3747 * everything this function may needs.
3748 */
3749 ret = process_client_msg(cmd_ctx);
3750 rcu_thread_offline();
3751 if (ret < 0) {
3752 /*
3753 * TODO: Inform client somehow of the fatal error. At
3754 * this point, ret < 0 means that a zmalloc failed
3755 * (ENOMEM). Error detected but still accept command.
3756 */
3757 clean_command_ctx(&cmd_ctx);
3758 continue;
3759 }
3760
3761 DBG("Sending response (size: %d, retcode: %s)",
3762 cmd_ctx->lttng_msg_size,
3763 lttng_strerror(-cmd_ctx->llm->ret_code));
3764 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3765 if (ret < 0) {
3766 ERR("Failed to send data back to client");
3767 }
3768
3769 /* End of transmission */
3770 close(sock);
3771
3772 clean_command_ctx(&cmd_ctx);
3773 }
3774
3775 error:
3776 DBG("Client thread dying");
3777 unlink(client_unix_sock_path);
3778 close(client_sock);
3779 close(sock);
3780
3781 lttng_poll_clean(&events);
3782 clean_command_ctx(&cmd_ctx);
3783
3784 rcu_unregister_thread();
3785 return NULL;
3786 }
3787
3788
3789 /*
3790 * usage function on stderr
3791 */
3792 static void usage(void)
3793 {
3794 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3795 fprintf(stderr, " -h, --help Display this usage.\n");
3796 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3797 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3798 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3799 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3800 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
3801 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
3802 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
3803 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
3804 fprintf(stderr, " --consumerd32-path PATH Specify path for the 32-bit UST consumer daemon binary\n");
3805 fprintf(stderr, " --consumerd32-libdir PATH Specify path for the 32-bit UST consumer daemon libraries\n");
3806 fprintf(stderr, " --consumerd64-path PATH Specify path for the 64-bit UST consumer daemon binary\n");
3807 fprintf(stderr, " --consumerd64-libdir PATH Specify path for the 64-bit UST consumer daemon libraries\n");
3808 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3809 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3810 fprintf(stderr, " -V, --version Show version number.\n");
3811 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3812 fprintf(stderr, " -q, --quiet No output at all.\n");
3813 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3814 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3815 fprintf(stderr, " --no-kernel Disable kernel tracer\n");
3816 }
3817
3818 /*
3819 * daemon argument parsing
3820 */
3821 static int parse_args(int argc, char **argv)
3822 {
3823 int c;
3824
3825 static struct option long_options[] = {
3826 { "client-sock", 1, 0, 'c' },
3827 { "apps-sock", 1, 0, 'a' },
3828 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3829 { "kconsumerd-err-sock", 1, 0, 'E' },
3830 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
3831 { "ustconsumerd32-err-sock", 1, 0, 'H' },
3832 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
3833 { "ustconsumerd64-err-sock", 1, 0, 'F' },
3834 { "consumerd32-path", 1, 0, 'u' },
3835 { "consumerd32-libdir", 1, 0, 'U' },
3836 { "consumerd64-path", 1, 0, 't' },
3837 { "consumerd64-libdir", 1, 0, 'T' },
3838 { "daemonize", 0, 0, 'd' },
3839 { "sig-parent", 0, 0, 'S' },
3840 { "help", 0, 0, 'h' },
3841 { "group", 1, 0, 'g' },
3842 { "version", 0, 0, 'V' },
3843 { "quiet", 0, 0, 'q' },
3844 { "verbose", 0, 0, 'v' },
3845 { "verbose-consumer", 0, 0, 'Z' },
3846 { "no-kernel", 0, 0, 'N' },
3847 { NULL, 0, 0, 0 }
3848 };
3849
3850 while (1) {
3851 int option_index = 0;
3852 c = getopt_long(argc, argv, "dhqvVSN" "a:c:g:s:C:E:D:F:Z:u:t",
3853 long_options, &option_index);
3854 if (c == -1) {
3855 break;
3856 }
3857
3858 switch (c) {
3859 case 0:
3860 fprintf(stderr, "option %s", long_options[option_index].name);
3861 if (optarg) {
3862 fprintf(stderr, " with arg %s\n", optarg);
3863 }
3864 break;
3865 case 'c':
3866 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3867 break;
3868 case 'a':
3869 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3870 break;
3871 case 'd':
3872 opt_daemon = 1;
3873 break;
3874 case 'g':
3875 opt_tracing_group = optarg;
3876 break;
3877 case 'h':
3878 usage();
3879 exit(EXIT_FAILURE);
3880 case 'V':
3881 fprintf(stdout, "%s\n", VERSION);
3882 exit(EXIT_SUCCESS);
3883 case 'S':
3884 opt_sig_parent = 1;
3885 break;
3886 case 'E':
3887 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3888 break;
3889 case 'C':
3890 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3891 break;
3892 case 'F':
3893 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3894 break;
3895 case 'D':
3896 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3897 break;
3898 case 'H':
3899 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3900 break;
3901 case 'G':
3902 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3903 break;
3904 case 'N':
3905 opt_no_kernel = 1;
3906 break;
3907 case 'q':
3908 opt_quiet = 1;
3909 break;
3910 case 'v':
3911 /* Verbose level can increase using multiple -v */
3912 opt_verbose += 1;
3913 break;
3914 case 'Z':
3915 opt_verbose_consumer += 1;
3916 break;
3917 case 'u':
3918 consumerd32_bin= optarg;
3919 break;
3920 case 'U':
3921 consumerd32_libdir = optarg;
3922 break;
3923 case 't':
3924 consumerd64_bin = optarg;
3925 break;
3926 case 'T':
3927 consumerd64_libdir = optarg;
3928 break;
3929 default:
3930 /* Unknown option or other error.
3931 * Error is printed by getopt, just return */
3932 return -1;
3933 }
3934 }
3935
3936 return 0;
3937 }
3938
3939 /*
3940 * Creates the two needed socket by the daemon.
3941 * apps_sock - The communication socket for all UST apps.
3942 * client_sock - The communication of the cli tool (lttng).
3943 */
3944 static int init_daemon_socket(void)
3945 {
3946 int ret = 0;
3947 mode_t old_umask;
3948
3949 old_umask = umask(0);
3950
3951 /* Create client tool unix socket */
3952 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3953 if (client_sock < 0) {
3954 ERR("Create unix sock failed: %s", client_unix_sock_path);
3955 ret = -1;
3956 goto end;
3957 }
3958
3959 /* File permission MUST be 660 */
3960 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3961 if (ret < 0) {
3962 ERR("Set file permissions failed: %s", client_unix_sock_path);
3963 perror("chmod");
3964 goto end;
3965 }
3966
3967 /* Create the application unix socket */
3968 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3969 if (apps_sock < 0) {
3970 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3971 ret = -1;
3972 goto end;
3973 }
3974
3975 /* File permission MUST be 666 */
3976 ret = chmod(apps_unix_sock_path,
3977 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3978 if (ret < 0) {
3979 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3980 perror("chmod");
3981 goto end;
3982 }
3983
3984 end:
3985 umask(old_umask);
3986 return ret;
3987 }
3988
3989 /*
3990 * Check if the global socket is available, and if a daemon is answering at the
3991 * other side. If yes, error is returned.
3992 */
3993 static int check_existing_daemon(void)
3994 {
3995 if (access(client_unix_sock_path, F_OK) < 0 &&
3996 access(apps_unix_sock_path, F_OK) < 0) {
3997 return 0;
3998 }
3999
4000 /* Is there anybody out there ? */
4001 if (lttng_session_daemon_alive()) {
4002 return -EEXIST;
4003 } else {
4004 return 0;
4005 }
4006 }
4007
4008 /*
4009 * Set the tracing group gid onto the client socket.
4010 *
4011 * Race window between mkdir and chown is OK because we are going from more
4012 * permissive (root.root) to les permissive (root.tracing).
4013 */
4014 static int set_permissions(char *rundir)
4015 {
4016 int ret;
4017 gid_t gid;
4018
4019 gid = allowed_group();
4020 if (gid < 0) {
4021 WARN("No tracing group detected");
4022 ret = 0;
4023 goto end;
4024 }
4025
4026 /* Set lttng run dir */
4027 ret = chown(rundir, 0, gid);
4028 if (ret < 0) {
4029 ERR("Unable to set group on %s", rundir);
4030 perror("chown");
4031 }
4032
4033 /* lttng client socket path */
4034 ret = chown(client_unix_sock_path, 0, gid);
4035 if (ret < 0) {
4036 ERR("Unable to set group on %s", client_unix_sock_path);
4037 perror("chown");
4038 }
4039
4040 /* kconsumer error socket path */
4041 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
4042 if (ret < 0) {
4043 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
4044 perror("chown");
4045 }
4046
4047 /* 64-bit ustconsumer error socket path */
4048 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
4049 if (ret < 0) {
4050 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
4051 perror("chown");
4052 }
4053
4054 /* 32-bit ustconsumer compat32 error socket path */
4055 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
4056 if (ret < 0) {
4057 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
4058 perror("chown");
4059 }
4060
4061 DBG("All permissions are set");
4062
4063 end:
4064 return ret;
4065 }
4066
4067 /*
4068 * Create the pipe used to wake up the kernel thread.
4069 */
4070 static int create_kernel_poll_pipe(void)
4071 {
4072 return pipe2(kernel_poll_pipe, O_CLOEXEC);
4073 }
4074
4075 /*
4076 * Create the application command pipe to wake thread_manage_apps.
4077 */
4078 static int create_apps_cmd_pipe(void)
4079 {
4080 return pipe2(apps_cmd_pipe, O_CLOEXEC);
4081 }
4082
4083 /*
4084 * Create the lttng run directory needed for all global sockets and pipe.
4085 */
4086 static int create_lttng_rundir(const char *rundir)
4087 {
4088 int ret;
4089
4090 DBG3("Creating LTTng run directory: %s", rundir);
4091
4092 ret = mkdir(rundir, S_IRWXU | S_IRWXG );
4093 if (ret < 0) {
4094 if (errno != EEXIST) {
4095 ERR("Unable to create %s", rundir);
4096 goto error;
4097 } else {
4098 ret = 0;
4099 }
4100 }
4101
4102 error:
4103 return ret;
4104 }
4105
4106 /*
4107 * Setup sockets and directory needed by the kconsumerd communication with the
4108 * session daemon.
4109 */
4110 static int set_consumer_sockets(struct consumer_data *consumer_data,
4111 const char *rundir)
4112 {
4113 int ret;
4114 char path[PATH_MAX];
4115
4116 switch (consumer_data->type) {
4117 case LTTNG_CONSUMER_KERNEL:
4118 snprintf(path, PATH_MAX, KCONSUMERD_PATH, rundir);
4119 break;
4120 case LTTNG_CONSUMER64_UST:
4121 snprintf(path, PATH_MAX, USTCONSUMERD64_PATH, rundir);
4122 break;
4123 case LTTNG_CONSUMER32_UST:
4124 snprintf(path, PATH_MAX, USTCONSUMERD32_PATH, rundir);
4125 break;
4126 default:
4127 ERR("Consumer type unknown");
4128 ret = -EINVAL;
4129 goto error;
4130 }
4131
4132 DBG2("Creating consumer directory: %s", path);
4133
4134 ret = mkdir(path, S_IRWXU | S_IRWXG);
4135 if (ret < 0) {
4136 if (errno != EEXIST) {
4137 ERR("Failed to create %s", path);
4138 goto error;
4139 }
4140 ret = 0;
4141 }
4142
4143 /* Create the kconsumerd error unix socket */
4144 consumer_data->err_sock =
4145 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
4146 if (consumer_data->err_sock < 0) {
4147 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
4148 ret = -1;
4149 goto error;
4150 }
4151
4152 /* File permission MUST be 660 */
4153 ret = chmod(consumer_data->err_unix_sock_path,
4154 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
4155 if (ret < 0) {
4156 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
4157 PERROR("chmod");
4158 goto error;
4159 }
4160
4161 error:
4162 return ret;
4163 }
4164
4165 /*
4166 * Signal handler for the daemon
4167 *
4168 * Simply stop all worker threads, leaving main() return gracefully after
4169 * joining all threads and calling cleanup().
4170 */
4171 static void sighandler(int sig)
4172 {
4173 switch (sig) {
4174 case SIGPIPE:
4175 DBG("SIGPIPE catched");
4176 return;
4177 case SIGINT:
4178 DBG("SIGINT catched");
4179 stop_threads();
4180 break;
4181 case SIGTERM:
4182 DBG("SIGTERM catched");
4183 stop_threads();
4184 break;
4185 default:
4186 break;
4187 }
4188 }
4189
4190 /*
4191 * Setup signal handler for :
4192 * SIGINT, SIGTERM, SIGPIPE
4193 */
4194 static int set_signal_handler(void)
4195 {
4196 int ret = 0;
4197 struct sigaction sa;
4198 sigset_t sigset;
4199
4200 if ((ret = sigemptyset(&sigset)) < 0) {
4201 perror("sigemptyset");
4202 return ret;
4203 }
4204
4205 sa.sa_handler = sighandler;
4206 sa.sa_mask = sigset;
4207 sa.sa_flags = 0;
4208 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
4209 perror("sigaction");
4210 return ret;
4211 }
4212
4213 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
4214 perror("sigaction");
4215 return ret;
4216 }
4217
4218 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
4219 perror("sigaction");
4220 return ret;
4221 }
4222
4223 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
4224
4225 return ret;
4226 }
4227
4228 /*
4229 * Set open files limit to unlimited. This daemon can open a large number of
4230 * file descriptors in order to consumer multiple kernel traces.
4231 */
4232 static void set_ulimit(void)
4233 {
4234 int ret;
4235 struct rlimit lim;
4236
4237 /* The kernel does not allowed an infinite limit for open files */
4238 lim.rlim_cur = 65535;
4239 lim.rlim_max = 65535;
4240
4241 ret = setrlimit(RLIMIT_NOFILE, &lim);
4242 if (ret < 0) {
4243 perror("failed to set open files limit");
4244 }
4245 }
4246
4247 /*
4248 * main
4249 */
4250 int main(int argc, char **argv)
4251 {
4252 int ret = 0;
4253 void *status;
4254 const char *home_path;
4255
4256 rcu_register_thread();
4257
4258 /* Create thread quit pipe */
4259 if ((ret = init_thread_quit_pipe()) < 0) {
4260 goto error;
4261 }
4262
4263 setup_consumerd_path();
4264
4265 /* Parse arguments */
4266 progname = argv[0];
4267 if ((ret = parse_args(argc, argv) < 0)) {
4268 goto error;
4269 }
4270
4271 /* Daemonize */
4272 if (opt_daemon) {
4273 ret = daemon(0, 0);
4274 if (ret < 0) {
4275 perror("daemon");
4276 goto error;
4277 }
4278 }
4279
4280 /* Check if daemon is UID = 0 */
4281 is_root = !getuid();
4282
4283 if (is_root) {
4284 rundir = strdup(LTTNG_RUNDIR);
4285
4286 /* Create global run dir with root access */
4287 ret = create_lttng_rundir(rundir);
4288 if (ret < 0) {
4289 goto error;
4290 }
4291
4292 if (strlen(apps_unix_sock_path) == 0) {
4293 snprintf(apps_unix_sock_path, PATH_MAX,
4294 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
4295 }
4296
4297 if (strlen(client_unix_sock_path) == 0) {
4298 snprintf(client_unix_sock_path, PATH_MAX,
4299 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
4300 }
4301
4302 /* Set global SHM for ust */
4303 if (strlen(wait_shm_path) == 0) {
4304 snprintf(wait_shm_path, PATH_MAX,
4305 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
4306 }
4307
4308 /* Setup kernel consumerd path */
4309 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX,
4310 KCONSUMERD_ERR_SOCK_PATH, rundir);
4311 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX,
4312 KCONSUMERD_CMD_SOCK_PATH, rundir);
4313
4314 DBG2("Kernel consumer err path: %s",
4315 kconsumer_data.err_unix_sock_path);
4316 DBG2("Kernel consumer cmd path: %s",
4317 kconsumer_data.cmd_unix_sock_path);
4318 } else {
4319 home_path = get_home_dir();
4320 if (home_path == NULL) {
4321 /* TODO: Add --socket PATH option */
4322 ERR("Can't get HOME directory for sockets creation.");
4323 ret = -EPERM;
4324 goto error;
4325 }
4326
4327 /*
4328 * Create rundir from home path. This will create something like
4329 * $HOME/.lttng
4330 */
4331 ret = asprintf(&rundir, LTTNG_HOME_RUNDIR, home_path);
4332 if (ret < 0) {
4333 ret = -ENOMEM;
4334 goto error;
4335 }
4336
4337 ret = create_lttng_rundir(rundir);
4338 if (ret < 0) {
4339 goto error;
4340 }
4341
4342 if (strlen(apps_unix_sock_path) == 0) {
4343 snprintf(apps_unix_sock_path, PATH_MAX,
4344 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
4345 }
4346
4347 /* Set the cli tool unix socket path */
4348 if (strlen(client_unix_sock_path) == 0) {
4349 snprintf(client_unix_sock_path, PATH_MAX,
4350 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
4351 }
4352
4353 /* Set global SHM for ust */
4354 if (strlen(wait_shm_path) == 0) {
4355 snprintf(wait_shm_path, PATH_MAX,
4356 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
4357 }
4358 }
4359
4360 DBG("Client socket path %s", client_unix_sock_path);
4361 DBG("Application socket path %s", apps_unix_sock_path);
4362 DBG("LTTng run directory path: %s", rundir);
4363
4364 /* 32 bits consumerd path setup */
4365 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX,
4366 USTCONSUMERD32_ERR_SOCK_PATH, rundir);
4367 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX,
4368 USTCONSUMERD32_CMD_SOCK_PATH, rundir);
4369
4370 DBG2("UST consumer 32 bits err path: %s",
4371 ustconsumer32_data.err_unix_sock_path);
4372 DBG2("UST consumer 32 bits cmd path: %s",
4373 ustconsumer32_data.cmd_unix_sock_path);
4374
4375 /* 64 bits consumerd path setup */
4376 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX,
4377 USTCONSUMERD64_ERR_SOCK_PATH, rundir);
4378 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX,
4379 USTCONSUMERD64_CMD_SOCK_PATH, rundir);
4380
4381 DBG2("UST consumer 64 bits err path: %s",
4382 ustconsumer64_data.err_unix_sock_path);
4383 DBG2("UST consumer 64 bits cmd path: %s",
4384 ustconsumer64_data.cmd_unix_sock_path);
4385
4386 /*
4387 * See if daemon already exist.
4388 */
4389 if ((ret = check_existing_daemon()) < 0) {
4390 ERR("Already running daemon.\n");
4391 /*
4392 * We do not goto exit because we must not cleanup()
4393 * because a daemon is already running.
4394 */
4395 goto error;
4396 }
4397
4398 /* After this point, we can safely call cleanup() with "goto exit" */
4399
4400 /*
4401 * These actions must be executed as root. We do that *after* setting up
4402 * the sockets path because we MUST make the check for another daemon using
4403 * those paths *before* trying to set the kernel consumer sockets and init
4404 * kernel tracer.
4405 */
4406 if (is_root) {
4407 ret = set_consumer_sockets(&kconsumer_data, rundir);
4408 if (ret < 0) {
4409 goto exit;
4410 }
4411
4412 /* Setup kernel tracer */
4413 if (!opt_no_kernel) {
4414 init_kernel_tracer();
4415 }
4416
4417 /* Set ulimit for open files */
4418 set_ulimit();
4419 }
4420
4421 ret = set_consumer_sockets(&ustconsumer64_data, rundir);
4422 if (ret < 0) {
4423 goto exit;
4424 }
4425
4426 ret = set_consumer_sockets(&ustconsumer32_data, rundir);
4427 if (ret < 0) {
4428 goto exit;
4429 }
4430
4431 if ((ret = set_signal_handler()) < 0) {
4432 goto exit;
4433 }
4434
4435 /* Setup the needed unix socket */
4436 if ((ret = init_daemon_socket()) < 0) {
4437 goto exit;
4438 }
4439
4440 /* Set credentials to socket */
4441 if (is_root && ((ret = set_permissions(rundir)) < 0)) {
4442 goto exit;
4443 }
4444
4445 /* Get parent pid if -S, --sig-parent is specified. */
4446 if (opt_sig_parent) {
4447 ppid = getppid();
4448 }
4449
4450 /* Setup the kernel pipe for waking up the kernel thread */
4451 if ((ret = create_kernel_poll_pipe()) < 0) {
4452 goto exit;
4453 }
4454
4455 /* Setup the thread apps communication pipe. */
4456 if ((ret = create_apps_cmd_pipe()) < 0) {
4457 goto exit;
4458 }
4459
4460 /* Init UST command queue. */
4461 cds_wfq_init(&ust_cmd_queue.queue);
4462
4463 /* Init UST app hash table */
4464 ust_app_ht_alloc();
4465
4466 /*
4467 * Get session list pointer. This pointer MUST NOT be free(). This list is
4468 * statically declared in session.c
4469 */
4470 session_list_ptr = session_get_list();
4471
4472 /* Set up max poll set size */
4473 lttng_poll_set_max_size();
4474
4475 /* Create thread to manage the client socket */
4476 ret = pthread_create(&client_thread, NULL,
4477 thread_manage_clients, (void *) NULL);
4478 if (ret != 0) {
4479 perror("pthread_create clients");
4480 goto exit_client;
4481 }
4482
4483 /* Create thread to dispatch registration */
4484 ret = pthread_create(&dispatch_thread, NULL,
4485 thread_dispatch_ust_registration, (void *) NULL);
4486 if (ret != 0) {
4487 perror("pthread_create dispatch");
4488 goto exit_dispatch;
4489 }
4490
4491 /* Create thread to manage application registration. */
4492 ret = pthread_create(&reg_apps_thread, NULL,
4493 thread_registration_apps, (void *) NULL);
4494 if (ret != 0) {
4495 perror("pthread_create registration");
4496 goto exit_reg_apps;
4497 }
4498
4499 /* Create thread to manage application socket */
4500 ret = pthread_create(&apps_thread, NULL,
4501 thread_manage_apps, (void *) NULL);
4502 if (ret != 0) {
4503 perror("pthread_create apps");
4504 goto exit_apps;
4505 }
4506
4507 /* Create kernel thread to manage kernel event */
4508 ret = pthread_create(&kernel_thread, NULL,
4509 thread_manage_kernel, (void *) NULL);
4510 if (ret != 0) {
4511 perror("pthread_create kernel");
4512 goto exit_kernel;
4513 }
4514
4515 ret = pthread_join(kernel_thread, &status);
4516 if (ret != 0) {
4517 perror("pthread_join");
4518 goto error; /* join error, exit without cleanup */
4519 }
4520
4521 exit_kernel:
4522 ret = pthread_join(apps_thread, &status);
4523 if (ret != 0) {
4524 perror("pthread_join");
4525 goto error; /* join error, exit without cleanup */
4526 }
4527
4528 exit_apps:
4529 ret = pthread_join(reg_apps_thread, &status);
4530 if (ret != 0) {
4531 perror("pthread_join");
4532 goto error; /* join error, exit without cleanup */
4533 }
4534
4535 exit_reg_apps:
4536 ret = pthread_join(dispatch_thread, &status);
4537 if (ret != 0) {
4538 perror("pthread_join");
4539 goto error; /* join error, exit without cleanup */
4540 }
4541
4542 exit_dispatch:
4543 ret = pthread_join(client_thread, &status);
4544 if (ret != 0) {
4545 perror("pthread_join");
4546 goto error; /* join error, exit without cleanup */
4547 }
4548
4549 ret = join_consumer_thread(&kconsumer_data);
4550 if (ret != 0) {
4551 perror("join_consumer");
4552 goto error; /* join error, exit without cleanup */
4553 }
4554
4555 exit_client:
4556 exit:
4557 /*
4558 * cleanup() is called when no other thread is running.
4559 */
4560 rcu_thread_online();
4561 cleanup();
4562 rcu_thread_offline();
4563 rcu_unregister_thread();
4564 if (!ret) {
4565 exit(EXIT_SUCCESS);
4566 }
4567 error:
4568 exit(EXIT_FAILURE);
4569 }
LTTng 2.0 tools and control repository
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