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Add debug statement to the teardown session
[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-sessiond-comm.h>
43 #include <lttng/lttng-consumer.h>
44
45 #include <lttngerr.h>
46
47 #include "channel.h"
48 #include "compat/poll.h"
49 #include "context.h"
50 #include "event.h"
51 #include "futex.h"
52 #include "hashtable.h"
53 #include "kernel-ctl.h"
54 #include "lttng-sessiond.h"
55 #include "shm.h"
56 #include "ust-app.h"
57 #include "ust-ctl.h"
58 #include "utils.h"
59
60 struct consumer_data {
61 enum lttng_consumer_type type;
62
63 pthread_t thread; /* Worker thread interacting with the consumer */
64 sem_t sem;
65
66 /* Mutex to control consumerd pid assignation */
67 pthread_mutex_t pid_mutex;
68 pid_t pid;
69
70 int err_sock;
71 int cmd_sock;
72
73 /* consumer error and command Unix socket path */
74 char err_unix_sock_path[PATH_MAX];
75 char cmd_unix_sock_path[PATH_MAX];
76 };
77
78 /* Const values */
79 const char default_home_dir[] = DEFAULT_HOME_DIR;
80 const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
81 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
82 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
83
84 /* Variables */
85 int opt_verbose; /* Not static for lttngerr.h */
86 int opt_verbose_consumer; /* Not static for lttngerr.h */
87 int opt_quiet; /* Not static for lttngerr.h */
88
89 const char *progname;
90 const char *opt_tracing_group;
91 static int opt_sig_parent;
92 static int opt_daemon;
93 static int is_root; /* Set to 1 if the daemon is running as root */
94 static pid_t ppid; /* Parent PID for --sig-parent option */
95
96 /* Consumer daemon specific control data */
97 static struct consumer_data kconsumer_data = {
98 .type = LTTNG_CONSUMER_KERNEL,
99 .err_unix_sock_path = KCONSUMERD_ERR_SOCK_PATH,
100 .cmd_unix_sock_path = KCONSUMERD_CMD_SOCK_PATH,
101 };
102 static struct consumer_data ustconsumer64_data = {
103 .type = LTTNG_CONSUMER64_UST,
104 .err_unix_sock_path = USTCONSUMERD64_ERR_SOCK_PATH,
105 .cmd_unix_sock_path = USTCONSUMERD64_CMD_SOCK_PATH,
106 };
107 static struct consumer_data ustconsumer32_data = {
108 .type = LTTNG_CONSUMER32_UST,
109 .err_unix_sock_path = USTCONSUMERD32_ERR_SOCK_PATH,
110 .cmd_unix_sock_path = USTCONSUMERD32_CMD_SOCK_PATH,
111 };
112
113 static int dispatch_thread_exit;
114
115 /* Global application Unix socket path */
116 static char apps_unix_sock_path[PATH_MAX];
117 /* Global client Unix socket path */
118 static char client_unix_sock_path[PATH_MAX];
119 /* global wait shm path for UST */
120 static char wait_shm_path[PATH_MAX];
121
122 /* Sockets and FDs */
123 static int client_sock;
124 static int apps_sock;
125 static int kernel_tracer_fd;
126 static int kernel_poll_pipe[2];
127
128 /*
129 * Quit pipe for all threads. This permits a single cancellation point
130 * for all threads when receiving an event on the pipe.
131 */
132 static int thread_quit_pipe[2];
133
134 /*
135 * This pipe is used to inform the thread managing application communication
136 * that a command is queued and ready to be processed.
137 */
138 static int apps_cmd_pipe[2];
139
140 /* Pthread, Mutexes and Semaphores */
141 static pthread_t apps_thread;
142 static pthread_t reg_apps_thread;
143 static pthread_t client_thread;
144 static pthread_t kernel_thread;
145 static pthread_t dispatch_thread;
146
147
148 /*
149 * UST registration command queue. This queue is tied with a futex and uses a N
150 * wakers / 1 waiter implemented and detailed in futex.c/.h
151 *
152 * The thread_manage_apps and thread_dispatch_ust_registration interact with
153 * this queue and the wait/wake scheme.
154 */
155 static struct ust_cmd_queue ust_cmd_queue;
156
157 /*
158 * Pointer initialized before thread creation.
159 *
160 * This points to the tracing session list containing the session count and a
161 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
162 * MUST NOT be taken if you call a public function in session.c.
163 *
164 * The lock is nested inside the structure: session_list_ptr->lock. Please use
165 * session_lock_list and session_unlock_list for lock acquisition.
166 */
167 static struct ltt_session_list *session_list_ptr;
168
169 int ust_consumerd64_fd = -1;
170 int ust_consumerd32_fd = -1;
171
172 static const char *consumerd64_prog = "lttng-consumerd";
173 static const char *consumerd32_prog = "lttng-consumerd";
174
175 static const char *consumerd64_bindir =
176 __stringify(CONFIG_64BIT_BINDIR);
177 static const char *consumerd32_bindir =
178 __stringify(CONFIG_32BIT_BINDIR);
179
180 static
181 void setup_consumerd_path(void)
182 {
183 const char *bindir;
184
185 /*
186 * Allow INSTALL_BIN_PATH to be used as a target path for the
187 * native architecture size consumer if CONFIG_NBIT_BINDIR as
188 * not been defined.
189 */
190 #if (CAA_BITS_PER_LONG == 64)
191 if (!consumerd64_bindir[0]) {
192 consumerd64_bindir = INSTALL_BIN_PATH;
193 }
194 #elif (CAA_BITS_PER_LONG == 32)
195 if (!consumerd32_bindir[0]) {
196 consumerd32_bindir = INSTALL_BIN_PATH;
197 }
198 #else
199 #error "Unknown bitness"
200 #endif
201
202 /*
203 * runtime env. var. overrides the build default.
204 */
205 bindir = getenv("LTTNG_TOOLS_64BIT_BINDIR");
206 if (bindir) {
207 consumerd64_bindir = bindir;
208 }
209 bindir = getenv("LTTNG_TOOLS_32BIT_BINDIR");
210 if (bindir) {
211 consumerd32_bindir = bindir;
212 }
213 }
214
215 /*
216 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
217 */
218 static int create_thread_poll_set(struct lttng_poll_event *events,
219 unsigned int size)
220 {
221 int ret;
222
223 if (events == NULL || size == 0) {
224 ret = -1;
225 goto error;
226 }
227
228 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
229 if (ret < 0) {
230 goto error;
231 }
232
233 /* Add quit pipe */
234 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
235 if (ret < 0) {
236 goto error;
237 }
238
239 return 0;
240
241 error:
242 return ret;
243 }
244
245 /*
246 * Check if the thread quit pipe was triggered.
247 *
248 * Return 1 if it was triggered else 0;
249 */
250 static int check_thread_quit_pipe(int fd, uint32_t events)
251 {
252 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
253 return 1;
254 }
255
256 return 0;
257 }
258
259 /*
260 * Remove modules in reverse load order.
261 */
262 static int modprobe_remove_kernel_modules(void)
263 {
264 int ret = 0, i;
265 char modprobe[256];
266
267 for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
268 ret = snprintf(modprobe, sizeof(modprobe),
269 "/sbin/modprobe -r -q %s",
270 kernel_modules_list[i].name);
271 if (ret < 0) {
272 perror("snprintf modprobe -r");
273 goto error;
274 }
275 modprobe[sizeof(modprobe) - 1] = '\0';
276 ret = system(modprobe);
277 if (ret == -1) {
278 ERR("Unable to launch modprobe -r for module %s",
279 kernel_modules_list[i].name);
280 } else if (kernel_modules_list[i].required
281 && WEXITSTATUS(ret) != 0) {
282 ERR("Unable to remove module %s",
283 kernel_modules_list[i].name);
284 } else {
285 DBG("Modprobe removal successful %s",
286 kernel_modules_list[i].name);
287 }
288 }
289
290 error:
291 return ret;
292 }
293
294 /*
295 * Return group ID of the tracing group or -1 if not found.
296 */
297 static gid_t allowed_group(void)
298 {
299 struct group *grp;
300
301 if (opt_tracing_group) {
302 grp = getgrnam(opt_tracing_group);
303 } else {
304 grp = getgrnam(default_tracing_group);
305 }
306 if (!grp) {
307 return -1;
308 } else {
309 return grp->gr_gid;
310 }
311 }
312
313 /*
314 * Init thread quit pipe.
315 *
316 * Return -1 on error or 0 if all pipes are created.
317 */
318 static int init_thread_quit_pipe(void)
319 {
320 int ret;
321
322 ret = pipe2(thread_quit_pipe, O_CLOEXEC);
323 if (ret < 0) {
324 perror("thread quit pipe");
325 goto error;
326 }
327
328 error:
329 return ret;
330 }
331
332 /*
333 * Complete teardown of a kernel session. This free all data structure related
334 * to a kernel session and update counter.
335 */
336 static void teardown_kernel_session(struct ltt_session *session)
337 {
338 if (!session->kernel_session) {
339 DBG3("No kernel session when tearingdown session");
340 return;
341 }
342
343 DBG("Tearing down kernel session");
344
345 /*
346 * If a custom kernel consumer was registered, close the socket before
347 * tearing down the complete kernel session structure
348 */
349 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
350 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
351 }
352
353 trace_kernel_destroy_session(session->kernel_session);
354 }
355
356 /*
357 * Complete teardown of all UST sessions. This will free everything on his path
358 * and destroy the core essence of all ust sessions :)
359 */
360 static void teardown_ust_session(struct ltt_session *session)
361 {
362 int ret;
363
364 if (!session->ust_session) {
365 DBG3("No UST session when tearingdown session");
366 return;
367 }
368
369 DBG("Tearing down UST session(s)");
370
371 ret = ust_app_destroy_trace_all(session->ust_session);
372 if (ret) {
373 ERR("Error in ust_app_destroy_trace_all");
374 }
375
376 trace_ust_destroy_session(session->ust_session);
377 }
378
379 /*
380 * Stop all threads by closing the thread quit pipe.
381 */
382 static void stop_threads(void)
383 {
384 int ret;
385
386 /* Stopping all threads */
387 DBG("Terminating all threads");
388 ret = notify_thread_pipe(thread_quit_pipe[1]);
389 if (ret < 0) {
390 ERR("write error on thread quit pipe");
391 }
392
393 /* Dispatch thread */
394 dispatch_thread_exit = 1;
395 futex_nto1_wake(&ust_cmd_queue.futex);
396 }
397
398 /*
399 * Cleanup the daemon
400 */
401 static void cleanup(void)
402 {
403 int ret;
404 char *cmd;
405 struct ltt_session *sess, *stmp;
406
407 DBG("Cleaning up");
408
409 if (is_root) {
410 DBG("Removing %s directory", LTTNG_RUNDIR);
411 ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
412 if (ret < 0) {
413 ERR("asprintf failed. Something is really wrong!");
414 }
415
416 /* Remove lttng run directory */
417 ret = system(cmd);
418 if (ret < 0) {
419 ERR("Unable to clean " LTTNG_RUNDIR);
420 }
421 }
422
423 DBG("Cleaning up all session");
424
425 /* Destroy session list mutex */
426 if (session_list_ptr != NULL) {
427 pthread_mutex_destroy(&session_list_ptr->lock);
428
429 /* Cleanup ALL session */
430 cds_list_for_each_entry_safe(sess, stmp,
431 &session_list_ptr->head, list) {
432 teardown_kernel_session(sess);
433 teardown_ust_session(sess);
434 free(sess);
435 }
436 }
437
438 DBG("Closing all UST sockets");
439 ust_app_clean_list();
440
441 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
442
443 DBG("Closing kernel fd");
444 close(kernel_tracer_fd);
445
446 if (is_root) {
447 DBG("Unloading kernel modules");
448 modprobe_remove_kernel_modules();
449 }
450
451 close(thread_quit_pipe[0]);
452 close(thread_quit_pipe[1]);
453
454 /* <fun> */
455 MSG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
456 "Matthew, BEET driven development works!%c[%dm",
457 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
458 /* </fun> */
459 }
460
461 /*
462 * Send data on a unix socket using the liblttsessiondcomm API.
463 *
464 * Return lttcomm error code.
465 */
466 static int send_unix_sock(int sock, void *buf, size_t len)
467 {
468 /* Check valid length */
469 if (len <= 0) {
470 return -1;
471 }
472
473 return lttcomm_send_unix_sock(sock, buf, len);
474 }
475
476 /*
477 * Free memory of a command context structure.
478 */
479 static void clean_command_ctx(struct command_ctx **cmd_ctx)
480 {
481 DBG("Clean command context structure");
482 if (*cmd_ctx) {
483 if ((*cmd_ctx)->llm) {
484 free((*cmd_ctx)->llm);
485 }
486 if ((*cmd_ctx)->lsm) {
487 free((*cmd_ctx)->lsm);
488 }
489 free(*cmd_ctx);
490 *cmd_ctx = NULL;
491 }
492 }
493
494 /*
495 * Send all stream fds of kernel channel to the consumer.
496 */
497 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
498 int sock, struct ltt_kernel_channel *channel)
499 {
500 int ret;
501 struct ltt_kernel_stream *stream;
502 struct lttcomm_consumer_msg lkm;
503
504 DBG("Sending streams of channel %s to kernel consumer",
505 channel->channel->name);
506
507 /* Send channel */
508 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
509 lkm.u.channel.channel_key = channel->fd;
510 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
511 lkm.u.channel.mmap_len = 0; /* for kernel */
512 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
513 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
514 if (ret < 0) {
515 perror("send consumer channel");
516 goto error;
517 }
518
519 /* Send streams */
520 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
521 if (!stream->fd) {
522 continue;
523 }
524 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
525 lkm.u.stream.channel_key = channel->fd;
526 lkm.u.stream.stream_key = stream->fd;
527 lkm.u.stream.state = stream->state;
528 lkm.u.stream.output = channel->channel->attr.output;
529 lkm.u.stream.mmap_len = 0; /* for kernel */
530 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
531 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
532 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
533 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
534 if (ret < 0) {
535 perror("send consumer stream");
536 goto error;
537 }
538 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
539 if (ret < 0) {
540 perror("send consumer stream ancillary data");
541 goto error;
542 }
543 }
544
545 DBG("consumer channel streams sent");
546
547 return 0;
548
549 error:
550 return ret;
551 }
552
553 /*
554 * Send all stream fds of the kernel session to the consumer.
555 */
556 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
557 struct ltt_kernel_session *session)
558 {
559 int ret;
560 struct ltt_kernel_channel *chan;
561 struct lttcomm_consumer_msg lkm;
562 int sock = session->consumer_fd;
563
564 DBG("Sending metadata stream fd");
565
566 /* Extra protection. It's NOT supposed to be set to 0 at this point */
567 if (session->consumer_fd == 0) {
568 session->consumer_fd = consumer_data->cmd_sock;
569 }
570
571 if (session->metadata_stream_fd != 0) {
572 /* Send metadata channel fd */
573 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
574 lkm.u.channel.channel_key = session->metadata->fd;
575 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
576 lkm.u.channel.mmap_len = 0; /* for kernel */
577 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
578 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
579 if (ret < 0) {
580 perror("send consumer channel");
581 goto error;
582 }
583
584 /* Send metadata stream fd */
585 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
586 lkm.u.stream.channel_key = session->metadata->fd;
587 lkm.u.stream.stream_key = session->metadata_stream_fd;
588 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
589 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
590 lkm.u.stream.mmap_len = 0; /* for kernel */
591 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
592 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
593 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
594 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
595 if (ret < 0) {
596 perror("send consumer stream");
597 goto error;
598 }
599 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
600 if (ret < 0) {
601 perror("send consumer stream");
602 goto error;
603 }
604 }
605
606 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
607 ret = send_kconsumer_channel_streams(consumer_data, sock, chan);
608 if (ret < 0) {
609 goto error;
610 }
611 }
612
613 DBG("consumer fds (metadata and channel streams) sent");
614
615 return 0;
616
617 error:
618 return ret;
619 }
620
621 /*
622 * Notify UST applications using the shm mmap futex.
623 */
624 static int notify_ust_apps(int active)
625 {
626 char *wait_shm_mmap;
627
628 DBG("Notifying applications of session daemon state: %d", active);
629
630 /* See shm.c for this call implying mmap, shm and futex calls */
631 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
632 if (wait_shm_mmap == NULL) {
633 goto error;
634 }
635
636 /* Wake waiting process */
637 futex_wait_update((int32_t *) wait_shm_mmap, active);
638
639 /* Apps notified successfully */
640 return 0;
641
642 error:
643 return -1;
644 }
645
646 /*
647 * Setup the outgoing data buffer for the response (llm) by allocating the
648 * right amount of memory and copying the original information from the lsm
649 * structure.
650 *
651 * Return total size of the buffer pointed by buf.
652 */
653 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
654 {
655 int ret, buf_size;
656
657 buf_size = size;
658
659 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
660 if (cmd_ctx->llm == NULL) {
661 perror("zmalloc");
662 ret = -ENOMEM;
663 goto error;
664 }
665
666 /* Copy common data */
667 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
668 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
669
670 cmd_ctx->llm->data_size = size;
671 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
672
673 return buf_size;
674
675 error:
676 return ret;
677 }
678
679 /*
680 * Update the kernel poll set of all channel fd available over all tracing
681 * session. Add the wakeup pipe at the end of the set.
682 */
683 static int update_kernel_poll(struct lttng_poll_event *events)
684 {
685 int ret;
686 struct ltt_session *session;
687 struct ltt_kernel_channel *channel;
688
689 DBG("Updating kernel poll set");
690
691 session_lock_list();
692 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
693 session_lock(session);
694 if (session->kernel_session == NULL) {
695 session_unlock(session);
696 continue;
697 }
698
699 cds_list_for_each_entry(channel,
700 &session->kernel_session->channel_list.head, list) {
701 /* Add channel fd to the kernel poll set */
702 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
703 if (ret < 0) {
704 session_unlock(session);
705 goto error;
706 }
707 DBG("Channel fd %d added to kernel set", channel->fd);
708 }
709 session_unlock(session);
710 }
711 session_unlock_list();
712
713 return 0;
714
715 error:
716 session_unlock_list();
717 return -1;
718 }
719
720 /*
721 * Find the channel fd from 'fd' over all tracing session. When found, check
722 * for new channel stream and send those stream fds to the kernel consumer.
723 *
724 * Useful for CPU hotplug feature.
725 */
726 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
727 {
728 int ret = 0;
729 struct ltt_session *session;
730 struct ltt_kernel_channel *channel;
731
732 DBG("Updating kernel streams for channel fd %d", fd);
733
734 session_lock_list();
735 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
736 session_lock(session);
737 if (session->kernel_session == NULL) {
738 session_unlock(session);
739 continue;
740 }
741
742 /* This is not suppose to be 0 but this is an extra security check */
743 if (session->kernel_session->consumer_fd == 0) {
744 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
745 }
746
747 cds_list_for_each_entry(channel,
748 &session->kernel_session->channel_list.head, list) {
749 if (channel->fd == fd) {
750 DBG("Channel found, updating kernel streams");
751 ret = kernel_open_channel_stream(channel);
752 if (ret < 0) {
753 goto error;
754 }
755
756 /*
757 * Have we already sent fds to the consumer? If yes, it means
758 * that tracing is started so it is safe to send our updated
759 * stream fds.
760 */
761 if (session->kernel_session->consumer_fds_sent == 1) {
762 ret = send_kconsumer_channel_streams(consumer_data,
763 session->kernel_session->consumer_fd, channel);
764 if (ret < 0) {
765 goto error;
766 }
767 }
768 goto error;
769 }
770 }
771 session_unlock(session);
772 }
773 session_unlock_list();
774 return ret;
775
776 error:
777 session_unlock(session);
778 session_unlock_list();
779 return ret;
780 }
781
782 /*
783 * For each tracing session, update newly registered apps.
784 */
785 static void update_ust_app(int app_sock)
786 {
787 struct ltt_session *sess, *stmp;
788
789 /* For all tracing session(s) */
790 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
791 if (sess->ust_session) {
792 ust_app_global_update(sess->ust_session, app_sock);
793 }
794 }
795 }
796
797 /*
798 * This thread manage event coming from the kernel.
799 *
800 * Features supported in this thread:
801 * -) CPU Hotplug
802 */
803 static void *thread_manage_kernel(void *data)
804 {
805 int ret, i, pollfd, update_poll_flag = 1;
806 uint32_t revents, nb_fd;
807 char tmp;
808 struct lttng_poll_event events;
809
810 DBG("Thread manage kernel started");
811
812 ret = create_thread_poll_set(&events, 2);
813 if (ret < 0) {
814 goto error;
815 }
816
817 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
818 if (ret < 0) {
819 goto error;
820 }
821
822 while (1) {
823 if (update_poll_flag == 1) {
824 /*
825 * Reset number of fd in the poll set. Always 2 since there is the thread
826 * quit pipe and the kernel pipe.
827 */
828 events.nb_fd = 2;
829
830 ret = update_kernel_poll(&events);
831 if (ret < 0) {
832 goto error;
833 }
834 update_poll_flag = 0;
835 }
836
837 nb_fd = LTTNG_POLL_GETNB(&events);
838
839 DBG("Thread kernel polling on %d fds", nb_fd);
840
841 /* Zeroed the poll events */
842 lttng_poll_reset(&events);
843
844 /* Poll infinite value of time */
845 ret = lttng_poll_wait(&events, -1);
846 if (ret < 0) {
847 goto error;
848 } else if (ret == 0) {
849 /* Should not happen since timeout is infinite */
850 ERR("Return value of poll is 0 with an infinite timeout.\n"
851 "This should not have happened! Continuing...");
852 continue;
853 }
854
855 for (i = 0; i < nb_fd; i++) {
856 /* Fetch once the poll data */
857 revents = LTTNG_POLL_GETEV(&events, i);
858 pollfd = LTTNG_POLL_GETFD(&events, i);
859
860 /* Thread quit pipe has been closed. Killing thread. */
861 ret = check_thread_quit_pipe(pollfd, revents);
862 if (ret) {
863 goto error;
864 }
865
866 /* Check for data on kernel pipe */
867 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
868 ret = read(kernel_poll_pipe[0], &tmp, 1);
869 update_poll_flag = 1;
870 continue;
871 } else {
872 /*
873 * New CPU detected by the kernel. Adding kernel stream to
874 * kernel session and updating the kernel consumer
875 */
876 if (revents & LPOLLIN) {
877 ret = update_kernel_stream(&kconsumer_data, pollfd);
878 if (ret < 0) {
879 continue;
880 }
881 break;
882 /*
883 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
884 * and unregister kernel stream at this point.
885 */
886 }
887 }
888 }
889 }
890
891 error:
892 DBG("Kernel thread dying");
893 close(kernel_poll_pipe[0]);
894 close(kernel_poll_pipe[1]);
895
896 lttng_poll_clean(&events);
897
898 return NULL;
899 }
900
901 /*
902 * This thread manage the consumer error sent back to the session daemon.
903 */
904 static void *thread_manage_consumer(void *data)
905 {
906 int sock = 0, i, ret, pollfd;
907 uint32_t revents, nb_fd;
908 enum lttcomm_return_code code;
909 struct lttng_poll_event events;
910 struct consumer_data *consumer_data = data;
911
912 DBG("[thread] Manage consumer started");
913
914 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
915 if (ret < 0) {
916 goto error;
917 }
918
919 /*
920 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
921 * Nothing more will be added to this poll set.
922 */
923 ret = create_thread_poll_set(&events, 2);
924 if (ret < 0) {
925 goto error;
926 }
927
928 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
929 if (ret < 0) {
930 goto error;
931 }
932
933 nb_fd = LTTNG_POLL_GETNB(&events);
934
935 /* Inifinite blocking call, waiting for transmission */
936 ret = lttng_poll_wait(&events, -1);
937 if (ret < 0) {
938 goto error;
939 }
940
941 for (i = 0; i < nb_fd; i++) {
942 /* Fetch once the poll data */
943 revents = LTTNG_POLL_GETEV(&events, i);
944 pollfd = LTTNG_POLL_GETFD(&events, i);
945
946 /* Thread quit pipe has been closed. Killing thread. */
947 ret = check_thread_quit_pipe(pollfd, revents);
948 if (ret) {
949 goto error;
950 }
951
952 /* Event on the registration socket */
953 if (pollfd == consumer_data->err_sock) {
954 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
955 ERR("consumer err socket poll error");
956 goto error;
957 }
958 }
959 }
960
961 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
962 if (sock < 0) {
963 goto error;
964 }
965
966 DBG2("Receiving code from consumer err_sock");
967
968 /* Getting status code from kconsumerd */
969 ret = lttcomm_recv_unix_sock(sock, &code,
970 sizeof(enum lttcomm_return_code));
971 if (ret <= 0) {
972 goto error;
973 }
974
975 if (code == CONSUMERD_COMMAND_SOCK_READY) {
976 consumer_data->cmd_sock =
977 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
978 if (consumer_data->cmd_sock < 0) {
979 sem_post(&consumer_data->sem);
980 PERROR("consumer connect");
981 goto error;
982 }
983 /* Signal condition to tell that the kconsumerd is ready */
984 sem_post(&consumer_data->sem);
985 DBG("consumer command socket ready");
986 } else {
987 ERR("consumer error when waiting for SOCK_READY : %s",
988 lttcomm_get_readable_code(-code));
989 goto error;
990 }
991
992 /* Remove the kconsumerd error sock since we've established a connexion */
993 ret = lttng_poll_del(&events, consumer_data->err_sock);
994 if (ret < 0) {
995 goto error;
996 }
997
998 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
999 if (ret < 0) {
1000 goto error;
1001 }
1002
1003 /* Update number of fd */
1004 nb_fd = LTTNG_POLL_GETNB(&events);
1005
1006 /* Inifinite blocking call, waiting for transmission */
1007 ret = lttng_poll_wait(&events, -1);
1008 if (ret < 0) {
1009 goto error;
1010 }
1011
1012 for (i = 0; i < nb_fd; i++) {
1013 /* Fetch once the poll data */
1014 revents = LTTNG_POLL_GETEV(&events, i);
1015 pollfd = LTTNG_POLL_GETFD(&events, i);
1016
1017 /* Thread quit pipe has been closed. Killing thread. */
1018 ret = check_thread_quit_pipe(pollfd, revents);
1019 if (ret) {
1020 goto error;
1021 }
1022
1023 /* Event on the kconsumerd socket */
1024 if (pollfd == sock) {
1025 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1026 ERR("consumer err socket second poll error");
1027 goto error;
1028 }
1029 }
1030 }
1031
1032 /* Wait for any kconsumerd error */
1033 ret = lttcomm_recv_unix_sock(sock, &code,
1034 sizeof(enum lttcomm_return_code));
1035 if (ret <= 0) {
1036 ERR("consumer closed the command socket");
1037 goto error;
1038 }
1039
1040 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1041
1042 error:
1043 DBG("consumer thread dying");
1044 close(consumer_data->err_sock);
1045 close(consumer_data->cmd_sock);
1046 close(sock);
1047
1048 unlink(consumer_data->err_unix_sock_path);
1049 unlink(consumer_data->cmd_unix_sock_path);
1050 consumer_data->pid = 0;
1051
1052 lttng_poll_clean(&events);
1053
1054 return NULL;
1055 }
1056
1057 /*
1058 * This thread manage application communication.
1059 */
1060 static void *thread_manage_apps(void *data)
1061 {
1062 int i, ret, pollfd;
1063 uint32_t revents, nb_fd;
1064 struct ust_command ust_cmd;
1065 struct lttng_poll_event events;
1066
1067 DBG("[thread] Manage application started");
1068
1069 rcu_register_thread();
1070 rcu_thread_online();
1071
1072 ret = create_thread_poll_set(&events, 2);
1073 if (ret < 0) {
1074 goto error;
1075 }
1076
1077 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1078 if (ret < 0) {
1079 goto error;
1080 }
1081
1082 while (1) {
1083 /* Zeroed the events structure */
1084 lttng_poll_reset(&events);
1085
1086 nb_fd = LTTNG_POLL_GETNB(&events);
1087
1088 DBG("Apps thread polling on %d fds", nb_fd);
1089
1090 /* Inifinite blocking call, waiting for transmission */
1091 ret = lttng_poll_wait(&events, -1);
1092 if (ret < 0) {
1093 goto error;
1094 }
1095
1096 for (i = 0; i < nb_fd; i++) {
1097 /* Fetch once the poll data */
1098 revents = LTTNG_POLL_GETEV(&events, i);
1099 pollfd = LTTNG_POLL_GETFD(&events, i);
1100
1101 /* Thread quit pipe has been closed. Killing thread. */
1102 ret = check_thread_quit_pipe(pollfd, revents);
1103 if (ret) {
1104 goto error;
1105 }
1106
1107 /* Inspect the apps cmd pipe */
1108 if (pollfd == apps_cmd_pipe[0]) {
1109 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1110 ERR("Apps command pipe error");
1111 goto error;
1112 } else if (revents & LPOLLIN) {
1113 /* Empty pipe */
1114 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1115 if (ret < 0 || ret < sizeof(ust_cmd)) {
1116 perror("read apps cmd pipe");
1117 goto error;
1118 }
1119
1120 /* Register applicaton to the session daemon */
1121 ret = ust_app_register(&ust_cmd.reg_msg,
1122 ust_cmd.sock);
1123 if (ret == -ENOMEM) {
1124 goto error;
1125 } else if (ret < 0) {
1126 break;
1127 }
1128
1129 /*
1130 * Add channel(s) and event(s) to newly registered apps
1131 * from lttng global UST domain.
1132 */
1133 update_ust_app(ust_cmd.sock);
1134
1135 ret = ustctl_register_done(ust_cmd.sock);
1136 if (ret < 0) {
1137 /*
1138 * If the registration is not possible, we simply
1139 * unregister the apps and continue
1140 */
1141 ust_app_unregister(ust_cmd.sock);
1142 } else {
1143 /*
1144 * We just need here to monitor the close of the UST
1145 * socket and poll set monitor those by default.
1146 */
1147 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1148 if (ret < 0) {
1149 goto error;
1150 }
1151
1152 DBG("Apps with sock %d added to poll set",
1153 ust_cmd.sock);
1154 }
1155
1156 break;
1157 }
1158 } else {
1159 /*
1160 * At this point, we know that a registered application made
1161 * the event at poll_wait.
1162 */
1163 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1164 /* Removing from the poll set */
1165 ret = lttng_poll_del(&events, pollfd);
1166 if (ret < 0) {
1167 goto error;
1168 }
1169
1170 /* Socket closed on remote end. */
1171 ust_app_unregister(pollfd);
1172 break;
1173 }
1174 }
1175 }
1176 }
1177
1178 error:
1179 DBG("Application communication apps dying");
1180 close(apps_cmd_pipe[0]);
1181 close(apps_cmd_pipe[1]);
1182
1183 lttng_poll_clean(&events);
1184
1185 rcu_thread_offline();
1186 rcu_unregister_thread();
1187 return NULL;
1188 }
1189
1190 /*
1191 * Dispatch request from the registration threads to the application
1192 * communication thread.
1193 */
1194 static void *thread_dispatch_ust_registration(void *data)
1195 {
1196 int ret;
1197 struct cds_wfq_node *node;
1198 struct ust_command *ust_cmd = NULL;
1199
1200 DBG("[thread] Dispatch UST command started");
1201
1202 while (!dispatch_thread_exit) {
1203 /* Atomically prepare the queue futex */
1204 futex_nto1_prepare(&ust_cmd_queue.futex);
1205
1206 do {
1207 /* Dequeue command for registration */
1208 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1209 if (node == NULL) {
1210 DBG("Woken up but nothing in the UST command queue");
1211 /* Continue thread execution */
1212 break;
1213 }
1214
1215 ust_cmd = caa_container_of(node, struct ust_command, node);
1216
1217 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1218 " gid:%d sock:%d name:%s (version %d.%d)",
1219 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1220 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1221 ust_cmd->sock, ust_cmd->reg_msg.name,
1222 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1223 /*
1224 * Inform apps thread of the new application registration. This
1225 * call is blocking so we can be assured that the data will be read
1226 * at some point in time or wait to the end of the world :)
1227 */
1228 ret = write(apps_cmd_pipe[1], ust_cmd,
1229 sizeof(struct ust_command));
1230 if (ret < 0) {
1231 perror("write apps cmd pipe");
1232 if (errno == EBADF) {
1233 /*
1234 * We can't inform the application thread to process
1235 * registration. We will exit or else application
1236 * registration will not occur and tracing will never
1237 * start.
1238 */
1239 goto error;
1240 }
1241 }
1242 free(ust_cmd);
1243 } while (node != NULL);
1244
1245 /* Futex wait on queue. Blocking call on futex() */
1246 futex_nto1_wait(&ust_cmd_queue.futex);
1247 }
1248
1249 error:
1250 DBG("Dispatch thread dying");
1251 return NULL;
1252 }
1253
1254 /*
1255 * This thread manage application registration.
1256 */
1257 static void *thread_registration_apps(void *data)
1258 {
1259 int sock = 0, i, ret, pollfd;
1260 uint32_t revents, nb_fd;
1261 struct lttng_poll_event events;
1262 /*
1263 * Get allocated in this thread, enqueued to a global queue, dequeued and
1264 * freed in the manage apps thread.
1265 */
1266 struct ust_command *ust_cmd = NULL;
1267
1268 DBG("[thread] Manage application registration started");
1269
1270 ret = lttcomm_listen_unix_sock(apps_sock);
1271 if (ret < 0) {
1272 goto error;
1273 }
1274
1275 /*
1276 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1277 * more will be added to this poll set.
1278 */
1279 ret = create_thread_poll_set(&events, 2);
1280 if (ret < 0) {
1281 goto error;
1282 }
1283
1284 /* Add the application registration socket */
1285 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1286 if (ret < 0) {
1287 goto error;
1288 }
1289
1290 /* Notify all applications to register */
1291 ret = notify_ust_apps(1);
1292 if (ret < 0) {
1293 ERR("Failed to notify applications or create the wait shared memory.\n"
1294 "Execution continues but there might be problem for already\n"
1295 "running applications that wishes to register.");
1296 }
1297
1298 while (1) {
1299 DBG("Accepting application registration");
1300
1301 nb_fd = LTTNG_POLL_GETNB(&events);
1302
1303 /* Inifinite blocking call, waiting for transmission */
1304 ret = lttng_poll_wait(&events, -1);
1305 if (ret < 0) {
1306 goto error;
1307 }
1308
1309 for (i = 0; i < nb_fd; i++) {
1310 /* Fetch once the poll data */
1311 revents = LTTNG_POLL_GETEV(&events, i);
1312 pollfd = LTTNG_POLL_GETFD(&events, i);
1313
1314 /* Thread quit pipe has been closed. Killing thread. */
1315 ret = check_thread_quit_pipe(pollfd, revents);
1316 if (ret) {
1317 goto error;
1318 }
1319
1320 /* Event on the registration socket */
1321 if (pollfd == apps_sock) {
1322 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1323 ERR("Register apps socket poll error");
1324 goto error;
1325 } else if (revents & LPOLLIN) {
1326 sock = lttcomm_accept_unix_sock(apps_sock);
1327 if (sock < 0) {
1328 goto error;
1329 }
1330
1331 /* Create UST registration command for enqueuing */
1332 ust_cmd = zmalloc(sizeof(struct ust_command));
1333 if (ust_cmd == NULL) {
1334 perror("ust command zmalloc");
1335 goto error;
1336 }
1337
1338 /*
1339 * Using message-based transmissions to ensure we don't
1340 * have to deal with partially received messages.
1341 */
1342 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1343 sizeof(struct ust_register_msg));
1344 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1345 if (ret < 0) {
1346 perror("lttcomm_recv_unix_sock register apps");
1347 } else {
1348 ERR("Wrong size received on apps register");
1349 }
1350 free(ust_cmd);
1351 close(sock);
1352 continue;
1353 }
1354
1355 ust_cmd->sock = sock;
1356
1357 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1358 " gid:%d sock:%d name:%s (version %d.%d)",
1359 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1360 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1361 ust_cmd->sock, ust_cmd->reg_msg.name,
1362 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1363
1364 /*
1365 * Lock free enqueue the registration request. The red pill
1366 * has been taken! This apps will be part of the *system*.
1367 */
1368 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1369
1370 /*
1371 * Wake the registration queue futex. Implicit memory
1372 * barrier with the exchange in cds_wfq_enqueue.
1373 */
1374 futex_nto1_wake(&ust_cmd_queue.futex);
1375 }
1376 }
1377 }
1378 }
1379
1380 error:
1381 DBG("UST Registration thread dying");
1382
1383 /* Notify that the registration thread is gone */
1384 notify_ust_apps(0);
1385
1386 close(apps_sock);
1387 close(sock);
1388 unlink(apps_unix_sock_path);
1389
1390 lttng_poll_clean(&events);
1391
1392 return NULL;
1393 }
1394
1395 /*
1396 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1397 * exec or it will fails.
1398 */
1399 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1400 {
1401 int ret;
1402 struct timespec timeout;
1403
1404 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1405 timeout.tv_nsec = 0;
1406
1407 /* Setup semaphore */
1408 ret = sem_init(&consumer_data->sem, 0, 0);
1409 if (ret < 0) {
1410 PERROR("sem_init consumer semaphore");
1411 goto error;
1412 }
1413
1414 ret = pthread_create(&consumer_data->thread, NULL,
1415 thread_manage_consumer, consumer_data);
1416 if (ret != 0) {
1417 PERROR("pthread_create consumer");
1418 ret = -1;
1419 goto error;
1420 }
1421
1422 /* Get time for sem_timedwait absolute timeout */
1423 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1424 if (ret < 0) {
1425 PERROR("clock_gettime spawn consumer");
1426 /* Infinite wait for the kconsumerd thread to be ready */
1427 ret = sem_wait(&consumer_data->sem);
1428 } else {
1429 /* Normal timeout if the gettime was successful */
1430 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1431 ret = sem_timedwait(&consumer_data->sem, &timeout);
1432 }
1433
1434 if (ret < 0) {
1435 if (errno == ETIMEDOUT) {
1436 /*
1437 * Call has timed out so we kill the kconsumerd_thread and return
1438 * an error.
1439 */
1440 ERR("The consumer thread was never ready. Killing it");
1441 ret = pthread_cancel(consumer_data->thread);
1442 if (ret < 0) {
1443 PERROR("pthread_cancel consumer thread");
1444 }
1445 } else {
1446 PERROR("semaphore wait failed consumer thread");
1447 }
1448 goto error;
1449 }
1450
1451 pthread_mutex_lock(&consumer_data->pid_mutex);
1452 if (consumer_data->pid == 0) {
1453 ERR("Kconsumerd did not start");
1454 pthread_mutex_unlock(&consumer_data->pid_mutex);
1455 goto error;
1456 }
1457 pthread_mutex_unlock(&consumer_data->pid_mutex);
1458
1459 return 0;
1460
1461 error:
1462 return ret;
1463 }
1464
1465 /*
1466 * Join consumer thread
1467 */
1468 static int join_consumer_thread(struct consumer_data *consumer_data)
1469 {
1470 void *status;
1471 int ret;
1472
1473 if (consumer_data->pid != 0) {
1474 ret = kill(consumer_data->pid, SIGTERM);
1475 if (ret) {
1476 ERR("Error killing consumer daemon");
1477 return ret;
1478 }
1479 return pthread_join(consumer_data->thread, &status);
1480 } else {
1481 return 0;
1482 }
1483 }
1484
1485 /*
1486 * Fork and exec a consumer daemon (consumerd).
1487 *
1488 * Return pid if successful else -1.
1489 */
1490 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1491 {
1492 int ret;
1493 pid_t pid;
1494 const char *verbosity;
1495
1496 DBG("Spawning consumerd");
1497
1498 pid = fork();
1499 if (pid == 0) {
1500 /*
1501 * Exec consumerd.
1502 */
1503 if (opt_verbose > 1 || opt_verbose_consumer) {
1504 verbosity = "--verbose";
1505 } else {
1506 verbosity = "--quiet";
1507 }
1508 switch (consumer_data->type) {
1509 case LTTNG_CONSUMER_KERNEL:
1510 execl(INSTALL_BIN_PATH "/lttng-consumerd",
1511 "lttng-consumerd", verbosity, "-k",
1512 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1513 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1514 NULL);
1515 break;
1516 case LTTNG_CONSUMER64_UST:
1517 {
1518 char path[PATH_MAX];
1519
1520 snprintf(path, PATH_MAX, "%s/%s",
1521 consumerd64_bindir, consumerd64_prog);
1522 execl(path, verbosity, "-u",
1523 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1524 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1525 NULL);
1526 break;
1527 }
1528 case LTTNG_CONSUMER32_UST:
1529 {
1530 char path[PATH_MAX];
1531
1532 snprintf(path, PATH_MAX, "%s/%s",
1533 consumerd32_bindir, consumerd32_prog);
1534 execl(path, verbosity, "-u",
1535 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1536 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1537 NULL);
1538 break;
1539 }
1540 default:
1541 perror("unknown consumer type");
1542 exit(EXIT_FAILURE);
1543 }
1544 if (errno != 0) {
1545 perror("kernel start consumer exec");
1546 }
1547 exit(EXIT_FAILURE);
1548 } else if (pid > 0) {
1549 ret = pid;
1550 } else {
1551 perror("start consumer fork");
1552 ret = -errno;
1553 }
1554 return ret;
1555 }
1556
1557 /*
1558 * Spawn the consumerd daemon and session daemon thread.
1559 */
1560 static int start_consumerd(struct consumer_data *consumer_data)
1561 {
1562 int ret;
1563
1564 pthread_mutex_lock(&consumer_data->pid_mutex);
1565 if (consumer_data->pid != 0) {
1566 pthread_mutex_unlock(&consumer_data->pid_mutex);
1567 goto end;
1568 }
1569
1570 ret = spawn_consumerd(consumer_data);
1571 if (ret < 0) {
1572 ERR("Spawning consumerd failed");
1573 pthread_mutex_unlock(&consumer_data->pid_mutex);
1574 goto error;
1575 }
1576
1577 /* Setting up the consumer_data pid */
1578 consumer_data->pid = ret;
1579 DBG2("Consumer pid %d", consumer_data->pid);
1580 pthread_mutex_unlock(&consumer_data->pid_mutex);
1581
1582 DBG2("Spawning consumer control thread");
1583 ret = spawn_consumer_thread(consumer_data);
1584 if (ret < 0) {
1585 ERR("Fatal error spawning consumer control thread");
1586 goto error;
1587 }
1588
1589 end:
1590 return 0;
1591
1592 error:
1593 return ret;
1594 }
1595
1596 /*
1597 * modprobe_kernel_modules
1598 */
1599 static int modprobe_kernel_modules(void)
1600 {
1601 int ret = 0, i;
1602 char modprobe[256];
1603
1604 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1605 ret = snprintf(modprobe, sizeof(modprobe),
1606 "/sbin/modprobe %s%s",
1607 kernel_modules_list[i].required ? "" : "-q ",
1608 kernel_modules_list[i].name);
1609 if (ret < 0) {
1610 perror("snprintf modprobe");
1611 goto error;
1612 }
1613 modprobe[sizeof(modprobe) - 1] = '\0';
1614 ret = system(modprobe);
1615 if (ret == -1) {
1616 ERR("Unable to launch modprobe for module %s",
1617 kernel_modules_list[i].name);
1618 } else if (kernel_modules_list[i].required
1619 && WEXITSTATUS(ret) != 0) {
1620 ERR("Unable to load module %s",
1621 kernel_modules_list[i].name);
1622 } else {
1623 DBG("Modprobe successfully %s",
1624 kernel_modules_list[i].name);
1625 }
1626 }
1627
1628 error:
1629 return ret;
1630 }
1631
1632 /*
1633 * mount_debugfs
1634 */
1635 static int mount_debugfs(char *path)
1636 {
1637 int ret;
1638 char *type = "debugfs";
1639
1640 ret = mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1641 if (ret < 0) {
1642 PERROR("Cannot create debugfs path");
1643 goto error;
1644 }
1645
1646 ret = mount(type, path, type, 0, NULL);
1647 if (ret < 0) {
1648 PERROR("Cannot mount debugfs");
1649 goto error;
1650 }
1651
1652 DBG("Mounted debugfs successfully at %s", path);
1653
1654 error:
1655 return ret;
1656 }
1657
1658 /*
1659 * Setup necessary data for kernel tracer action.
1660 */
1661 static void init_kernel_tracer(void)
1662 {
1663 int ret;
1664 char *proc_mounts = "/proc/mounts";
1665 char line[256];
1666 char *debugfs_path = NULL, *lttng_path = NULL;
1667 FILE *fp;
1668
1669 /* Detect debugfs */
1670 fp = fopen(proc_mounts, "r");
1671 if (fp == NULL) {
1672 ERR("Unable to probe %s", proc_mounts);
1673 goto error;
1674 }
1675
1676 while (fgets(line, sizeof(line), fp) != NULL) {
1677 if (strstr(line, "debugfs") != NULL) {
1678 /* Remove first string */
1679 strtok(line, " ");
1680 /* Dup string here so we can reuse line later on */
1681 debugfs_path = strdup(strtok(NULL, " "));
1682 DBG("Got debugfs path : %s", debugfs_path);
1683 break;
1684 }
1685 }
1686
1687 fclose(fp);
1688
1689 /* Mount debugfs if needded */
1690 if (debugfs_path == NULL) {
1691 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1692 if (ret < 0) {
1693 perror("asprintf debugfs path");
1694 goto error;
1695 }
1696 ret = mount_debugfs(debugfs_path);
1697 if (ret < 0) {
1698 perror("Cannot mount debugfs");
1699 goto error;
1700 }
1701 }
1702
1703 /* Modprobe lttng kernel modules */
1704 ret = modprobe_kernel_modules();
1705 if (ret < 0) {
1706 goto error;
1707 }
1708
1709 /* Setup lttng kernel path */
1710 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1711 if (ret < 0) {
1712 perror("asprintf lttng path");
1713 goto error;
1714 }
1715
1716 /* Open debugfs lttng */
1717 kernel_tracer_fd = open(lttng_path, O_RDWR);
1718 if (kernel_tracer_fd < 0) {
1719 DBG("Failed to open %s", lttng_path);
1720 goto error;
1721 }
1722
1723 free(lttng_path);
1724 free(debugfs_path);
1725 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1726 return;
1727
1728 error:
1729 if (lttng_path) {
1730 free(lttng_path);
1731 }
1732 if (debugfs_path) {
1733 free(debugfs_path);
1734 }
1735 WARN("No kernel tracer available");
1736 kernel_tracer_fd = 0;
1737 return;
1738 }
1739
1740 /*
1741 * Init tracing by creating trace directory and sending fds kernel consumer.
1742 */
1743 static int init_kernel_tracing(struct ltt_kernel_session *session)
1744 {
1745 int ret = 0;
1746
1747 if (session->consumer_fds_sent == 0) {
1748 /*
1749 * Assign default kernel consumer socket if no consumer assigned to the
1750 * kernel session. At this point, it's NOT suppose to be 0 but this is
1751 * an extra security check.
1752 */
1753 if (session->consumer_fd == 0) {
1754 session->consumer_fd = kconsumer_data.cmd_sock;
1755 }
1756
1757 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1758 if (ret < 0) {
1759 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1760 goto error;
1761 }
1762
1763 session->consumer_fds_sent = 1;
1764 }
1765
1766 error:
1767 return ret;
1768 }
1769
1770 /*
1771 * Create an UST session and add it to the session ust list.
1772 */
1773 static int create_ust_session(struct ltt_session *session,
1774 struct lttng_domain *domain)
1775 {
1776 int ret;
1777 unsigned int uid;
1778 struct ltt_ust_session *lus = NULL;
1779
1780 switch (domain->type) {
1781 case LTTNG_DOMAIN_UST:
1782 break;
1783 default:
1784 ret = LTTCOMM_UNKNOWN_DOMAIN;
1785 goto error;
1786 }
1787
1788 DBG("Creating UST session");
1789
1790 uid = session->uid;
1791 lus = trace_ust_create_session(session->path, uid, domain);
1792 if (lus == NULL) {
1793 ret = LTTCOMM_UST_SESS_FAIL;
1794 goto error;
1795 }
1796
1797 ret = mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1798 geteuid(), allowed_group());
1799 if (ret < 0) {
1800 if (ret != -EEXIST) {
1801 ERR("Trace directory creation error");
1802 ret = LTTCOMM_UST_SESS_FAIL;
1803 goto error;
1804 }
1805 }
1806
1807 /* The domain type dictate different actions on session creation */
1808 switch (domain->type) {
1809 case LTTNG_DOMAIN_UST:
1810 /* No ustctl for the global UST domain */
1811 break;
1812 default:
1813 ERR("Unknown UST domain on create session %d", domain->type);
1814 goto error;
1815 }
1816 session->ust_session = lus;
1817
1818 return LTTCOMM_OK;
1819
1820 error:
1821 free(lus);
1822 return ret;
1823 }
1824
1825 /*
1826 * Create a kernel tracer session then create the default channel.
1827 */
1828 static int create_kernel_session(struct ltt_session *session)
1829 {
1830 int ret;
1831
1832 DBG("Creating kernel session");
1833
1834 ret = kernel_create_session(session, kernel_tracer_fd);
1835 if (ret < 0) {
1836 ret = LTTCOMM_KERN_SESS_FAIL;
1837 goto error;
1838 }
1839
1840 /* Set kernel consumer socket fd */
1841 if (kconsumer_data.cmd_sock) {
1842 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1843 }
1844
1845 ret = mkdir_recursive(session->kernel_session->trace_path,
1846 S_IRWXU | S_IRWXG, geteuid(), allowed_group());
1847 if (ret < 0) {
1848 if (ret != -EEXIST) {
1849 ERR("Trace directory creation error");
1850 goto error;
1851 }
1852 }
1853
1854 error:
1855 return ret;
1856 }
1857
1858 /*
1859 * Using the session list, filled a lttng_session array to send back to the
1860 * client for session listing.
1861 *
1862 * The session list lock MUST be acquired before calling this function. Use
1863 * session_lock_list() and session_unlock_list().
1864 */
1865 static void list_lttng_sessions(struct lttng_session *sessions)
1866 {
1867 int i = 0;
1868 struct ltt_session *session;
1869
1870 DBG("Getting all available session");
1871 /*
1872 * Iterate over session list and append data after the control struct in
1873 * the buffer.
1874 */
1875 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1876 strncpy(sessions[i].path, session->path, PATH_MAX);
1877 sessions[i].path[PATH_MAX - 1] = '\0';
1878 strncpy(sessions[i].name, session->name, NAME_MAX);
1879 sessions[i].name[NAME_MAX - 1] = '\0';
1880 sessions[i].enabled = session->enabled;
1881 i++;
1882 }
1883 }
1884
1885 /*
1886 * Fill lttng_channel array of all channels.
1887 */
1888 static void list_lttng_channels(int domain, struct ltt_session *session,
1889 struct lttng_channel *channels)
1890 {
1891 int i = 0;
1892 struct ltt_kernel_channel *kchan;
1893
1894 DBG("Listing channels for session %s", session->name);
1895
1896 switch (domain) {
1897 case LTTNG_DOMAIN_KERNEL:
1898 /* Kernel channels */
1899 if (session->kernel_session != NULL) {
1900 cds_list_for_each_entry(kchan,
1901 &session->kernel_session->channel_list.head, list) {
1902 /* Copy lttng_channel struct to array */
1903 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
1904 channels[i].enabled = kchan->enabled;
1905 i++;
1906 }
1907 }
1908 break;
1909 case LTTNG_DOMAIN_UST:
1910 {
1911 struct cds_lfht_iter iter;
1912 struct ltt_ust_channel *uchan;
1913
1914 cds_lfht_for_each_entry(session->ust_session->domain_global.channels,
1915 &iter, uchan, node) {
1916 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
1917 channels[i].attr.overwrite = uchan->attr.overwrite;
1918 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
1919 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
1920 channels[i].attr.switch_timer_interval =
1921 uchan->attr.switch_timer_interval;
1922 channels[i].attr.read_timer_interval =
1923 uchan->attr.read_timer_interval;
1924 channels[i].attr.output = uchan->attr.output;
1925 i++;
1926 }
1927 break;
1928 }
1929 default:
1930 break;
1931 }
1932 }
1933
1934 /*
1935 * Create a list of ust global domain events.
1936 */
1937 static int list_lttng_ust_global_events(char *channel_name,
1938 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
1939 {
1940 int i = 0, ret = 0;
1941 unsigned int nb_event = 0;
1942 struct cds_lfht_iter iter;
1943 struct ltt_ust_channel *uchan;
1944 struct ltt_ust_event *uevent;
1945 struct lttng_event *tmp;
1946
1947 DBG("Listing UST global events for channel %s", channel_name);
1948
1949 rcu_read_lock();
1950
1951 /* Count events in all channels */
1952 cds_lfht_for_each_entry(ust_global->channels, &iter, uchan, node) {
1953 nb_event += hashtable_get_count(uchan->events);
1954 }
1955
1956 if (nb_event == 0) {
1957 ret = nb_event;
1958 goto error;
1959 }
1960
1961 DBG3("Listing UST global %d events", nb_event);
1962
1963 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
1964 if (tmp == NULL) {
1965 ret = -LTTCOMM_FATAL;
1966 goto error;
1967 }
1968
1969 cds_lfht_for_each_entry(ust_global->channels, &iter, uchan, node) {
1970 cds_lfht_for_each_entry(uchan->events, &iter, uevent, node) {
1971 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
1972 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
1973 tmp[i].enabled = uevent->enabled;
1974 switch (uevent->attr.instrumentation) {
1975 case LTTNG_UST_TRACEPOINT:
1976 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
1977 break;
1978 case LTTNG_UST_PROBE:
1979 tmp[i].type = LTTNG_EVENT_PROBE;
1980 break;
1981 case LTTNG_UST_FUNCTION:
1982 tmp[i].type = LTTNG_EVENT_FUNCTION;
1983 break;
1984 }
1985 i++;
1986 }
1987 }
1988
1989 ret = nb_event;
1990 *events = tmp;
1991
1992 error:
1993 rcu_read_unlock();
1994 return ret;
1995 }
1996
1997 /*
1998 * Fill lttng_event array of all kernel events in the channel.
1999 */
2000 static int list_lttng_kernel_events(char *channel_name,
2001 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2002 {
2003 int i = 0, ret;
2004 unsigned int nb_event;
2005 struct ltt_kernel_event *event;
2006 struct ltt_kernel_channel *kchan;
2007
2008 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2009 if (kchan == NULL) {
2010 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2011 goto error;
2012 }
2013
2014 nb_event = kchan->event_count;
2015
2016 DBG("Listing events for channel %s", kchan->channel->name);
2017
2018 if (nb_event == 0) {
2019 ret = nb_event;
2020 goto error;
2021 }
2022
2023 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2024 if (*events == NULL) {
2025 ret = LTTCOMM_FATAL;
2026 goto error;
2027 }
2028
2029 /* Kernel channels */
2030 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2031 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2032 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2033 (*events)[i].enabled = event->enabled;
2034 switch (event->event->instrumentation) {
2035 case LTTNG_KERNEL_TRACEPOINT:
2036 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2037 break;
2038 case LTTNG_KERNEL_KPROBE:
2039 case LTTNG_KERNEL_KRETPROBE:
2040 (*events)[i].type = LTTNG_EVENT_PROBE;
2041 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2042 sizeof(struct lttng_kernel_kprobe));
2043 break;
2044 case LTTNG_KERNEL_FUNCTION:
2045 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2046 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2047 sizeof(struct lttng_kernel_function));
2048 break;
2049 case LTTNG_KERNEL_NOOP:
2050 (*events)[i].type = LTTNG_EVENT_NOOP;
2051 break;
2052 case LTTNG_KERNEL_SYSCALL:
2053 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2054 break;
2055 case LTTNG_KERNEL_ALL:
2056 assert(0);
2057 break;
2058 }
2059 i++;
2060 }
2061
2062 return nb_event;
2063
2064 error:
2065 return ret;
2066 }
2067
2068 /*
2069 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2070 */
2071 static int cmd_disable_channel(struct ltt_session *session,
2072 int domain, char *channel_name)
2073 {
2074 int ret;
2075
2076 switch (domain) {
2077 case LTTNG_DOMAIN_KERNEL:
2078 ret = channel_kernel_disable(session->kernel_session,
2079 channel_name);
2080 if (ret != LTTCOMM_OK) {
2081 goto error;
2082 }
2083
2084 kernel_wait_quiescent(kernel_tracer_fd);
2085 break;
2086 case LTTNG_DOMAIN_UST_PID:
2087 break;
2088 default:
2089 ret = LTTCOMM_UNKNOWN_DOMAIN;
2090 goto error;
2091 }
2092
2093 ret = LTTCOMM_OK;
2094
2095 error:
2096 return ret;
2097 }
2098
2099 /*
2100 * Copy channel from attributes and set it in the application channel list.
2101 */
2102 /*
2103 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
2104 struct lttng_channel *attr, struct ust_app *app)
2105 {
2106 int ret;
2107 struct ltt_ust_channel *uchan, *new_chan;
2108
2109 uchan = trace_ust_get_channel_by_key(usess->channels, attr->name);
2110 if (uchan == NULL) {
2111 ret = LTTCOMM_FATAL;
2112 goto error;
2113 }
2114
2115 new_chan = trace_ust_create_channel(attr, usess->path);
2116 if (new_chan == NULL) {
2117 PERROR("malloc ltt_ust_channel");
2118 ret = LTTCOMM_FATAL;
2119 goto error;
2120 }
2121
2122 ret = channel_ust_copy(new_chan, uchan);
2123 if (ret < 0) {
2124 ret = LTTCOMM_FATAL;
2125 goto error;
2126 }
2127
2128 error:
2129 return ret;
2130 }
2131 */
2132
2133 /*
2134 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2135 */
2136 static int cmd_enable_channel(struct ltt_session *session,
2137 struct lttng_domain *domain, struct lttng_channel *attr)
2138 {
2139 int ret;
2140 struct ltt_ust_session *usess = session->ust_session;
2141
2142 DBG("Enabling channel %s for session %s", attr->name, session->name);
2143
2144 switch (domain->type) {
2145 case LTTNG_DOMAIN_KERNEL:
2146 {
2147 struct ltt_kernel_channel *kchan;
2148
2149 kchan = trace_kernel_get_channel_by_name(attr->name,
2150 session->kernel_session);
2151 if (kchan == NULL) {
2152 ret = channel_kernel_create(session->kernel_session,
2153 attr, kernel_poll_pipe[1]);
2154 } else {
2155 ret = channel_kernel_enable(session->kernel_session, kchan);
2156 }
2157
2158 if (ret != LTTCOMM_OK) {
2159 goto error;
2160 }
2161
2162 kernel_wait_quiescent(kernel_tracer_fd);
2163 break;
2164 }
2165 case LTTNG_DOMAIN_UST:
2166 {
2167 struct ltt_ust_channel *uchan;
2168
2169 DBG2("Enabling channel for LTTNG_DOMAIN_UST");
2170
2171 /* Get channel in global UST domain HT */
2172 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2173 attr->name);
2174 if (uchan == NULL) {
2175 uchan = trace_ust_create_channel(attr, usess->pathname);
2176 if (uchan == NULL) {
2177 ret = LTTCOMM_UST_CHAN_FAIL;
2178 goto error;
2179 }
2180
2181 rcu_read_lock();
2182 hashtable_add_unique(usess->domain_global.channels, &uchan->node);
2183 rcu_read_unlock();
2184 DBG2("UST channel %s added to global domain HT", attr->name);
2185 } else {
2186 ret = LTTCOMM_UST_CHAN_EXIST;
2187 goto error;
2188 }
2189
2190 /* Add channel to all registered applications */
2191 ret = ust_app_create_channel_all(usess, uchan);
2192 if (ret != 0) {
2193 goto error;
2194 }
2195
2196 uchan->enabled = 1;
2197
2198 break;
2199 }
2200 case LTTNG_DOMAIN_UST_PID:
2201 {
2202 /*
2203 int sock;
2204 struct ltt_ust_channel *uchan;
2205 struct ltt_ust_session *usess;
2206 struct ust_app *app;
2207
2208 usess = trace_ust_get_session_by_pid(&session->ust_session_list,
2209 domain->attr.pid);
2210 if (usess == NULL) {
2211 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2212 goto error;
2213 }
2214
2215 app = ust_app_get_by_pid(domain->attr.pid);
2216 if (app == NULL) {
2217 ret = LTTCOMM_APP_NOT_FOUND;
2218 goto error;
2219 }
2220 sock = app->sock;
2221
2222 uchan = trace_ust_get_channel_by_name(attr->name, usess);
2223 if (uchan == NULL) {
2224 ret = channel_ust_create(usess, attr, sock);
2225 } else {
2226 ret = channel_ust_enable(usess, uchan, sock);
2227 }
2228
2229 if (ret != LTTCOMM_OK) {
2230 goto error;
2231 }
2232
2233 ret = copy_ust_channel_to_app(usess, attr, app);
2234 if (ret != LTTCOMM_OK) {
2235 goto error;
2236 }
2237
2238 DBG("UST channel %s created for app sock %d with pid %d",
2239 attr->name, app->sock, domain->attr.pid);
2240 */
2241 ret = LTTCOMM_NOT_IMPLEMENTED;
2242 goto error;
2243 }
2244 default:
2245 ret = LTTCOMM_UNKNOWN_DOMAIN;
2246 goto error;
2247 }
2248
2249 ret = LTTCOMM_OK;
2250
2251 error:
2252 return ret;
2253 }
2254
2255 /*
2256 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2257 */
2258 static int cmd_disable_event(struct ltt_session *session, int domain,
2259 char *channel_name, char *event_name)
2260 {
2261 int ret;
2262
2263 switch (domain) {
2264 case LTTNG_DOMAIN_KERNEL:
2265 {
2266 struct ltt_kernel_channel *kchan;
2267
2268 kchan = trace_kernel_get_channel_by_name(channel_name,
2269 session->kernel_session);
2270 if (kchan == NULL) {
2271 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2272 goto error;
2273 }
2274
2275 ret = event_kernel_disable_tracepoint(session->kernel_session, kchan, event_name);
2276 if (ret != LTTCOMM_OK) {
2277 goto error;
2278 }
2279
2280 kernel_wait_quiescent(kernel_tracer_fd);
2281 break;
2282 }
2283 case LTTNG_DOMAIN_UST:
2284 case LTTNG_DOMAIN_UST_EXEC_NAME:
2285 case LTTNG_DOMAIN_UST_PID:
2286 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2287 default:
2288 /* TODO: Other UST domains */
2289 ret = LTTCOMM_NOT_IMPLEMENTED;
2290 goto error;
2291 }
2292
2293 ret = LTTCOMM_OK;
2294
2295 error:
2296 return ret;
2297 }
2298
2299 /*
2300 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2301 */
2302 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2303 char *channel_name)
2304 {
2305 int ret;
2306 struct ltt_kernel_channel *kchan;
2307
2308 switch (domain) {
2309 case LTTNG_DOMAIN_KERNEL:
2310 kchan = trace_kernel_get_channel_by_name(channel_name,
2311 session->kernel_session);
2312 if (kchan == NULL) {
2313 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2314 goto error;
2315 }
2316
2317 ret = event_kernel_disable_all(session->kernel_session, kchan);
2318 if (ret != LTTCOMM_OK) {
2319 goto error;
2320 }
2321
2322 kernel_wait_quiescent(kernel_tracer_fd);
2323 break;
2324 default:
2325 /* TODO: Userspace tracing */
2326 ret = LTTCOMM_NOT_IMPLEMENTED;
2327 goto error;
2328 }
2329
2330 ret = LTTCOMM_OK;
2331
2332 error:
2333 return ret;
2334 }
2335
2336 /*
2337 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2338 */
2339 static int cmd_add_context(struct ltt_session *session, int domain,
2340 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2341 {
2342 int ret;
2343
2344 switch (domain) {
2345 case LTTNG_DOMAIN_KERNEL:
2346 /* Add kernel context to kernel tracer */
2347 ret = context_kernel_add(session->kernel_session, ctx,
2348 event_name, channel_name);
2349 if (ret != LTTCOMM_OK) {
2350 goto error;
2351 }
2352 break;
2353 case LTTNG_DOMAIN_UST:
2354 {
2355 /*
2356 struct ltt_ust_session *usess;
2357
2358 cds_list_for_each_entry(usess, &session->ust_session_list.head, list) {
2359 ret = context_ust_add(usess, ctx,
2360 event_name, channel_name, domain);
2361 if (ret != LTTCOMM_OK) {
2362 goto error;
2363 }
2364 }
2365 break;
2366 */
2367 }
2368 default:
2369 /* TODO: UST other domains */
2370 ret = LTTCOMM_NOT_IMPLEMENTED;
2371 goto error;
2372 }
2373
2374 ret = LTTCOMM_OK;
2375
2376 error:
2377 return ret;
2378 }
2379
2380 /*
2381 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2382 */
2383 static int cmd_enable_event(struct ltt_session *session, int domain,
2384 char *channel_name, struct lttng_event *event)
2385 {
2386 int ret;
2387 struct lttng_channel *attr;
2388 struct ltt_ust_session *usess = session->ust_session;
2389
2390 switch (domain) {
2391 case LTTNG_DOMAIN_KERNEL:
2392 {
2393 struct ltt_kernel_channel *kchan;
2394
2395 kchan = trace_kernel_get_channel_by_name(channel_name,
2396 session->kernel_session);
2397 if (kchan == NULL) {
2398 attr = channel_new_default_attr(domain);
2399 if (attr == NULL) {
2400 ret = LTTCOMM_FATAL;
2401 goto error;
2402 }
2403 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2404
2405 /* This call will notify the kernel thread */
2406 ret = channel_kernel_create(session->kernel_session,
2407 attr, kernel_poll_pipe[1]);
2408 if (ret != LTTCOMM_OK) {
2409 goto error;
2410 }
2411 }
2412
2413 /* Get the newly created kernel channel pointer */
2414 kchan = trace_kernel_get_channel_by_name(channel_name,
2415 session->kernel_session);
2416 if (kchan == NULL) {
2417 /* This sould not happen... */
2418 ret = LTTCOMM_FATAL;
2419 goto error;
2420 }
2421
2422 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2423 event);
2424 if (ret != LTTCOMM_OK) {
2425 goto error;
2426 }
2427
2428 kernel_wait_quiescent(kernel_tracer_fd);
2429 break;
2430 }
2431 case LTTNG_DOMAIN_UST:
2432 {
2433 struct ltt_ust_channel *uchan;
2434 struct ltt_ust_event *uevent;
2435
2436 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2437 channel_name);
2438 if (uchan == NULL) {
2439 /* TODO: Create default channel */
2440 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2441 goto error;
2442 }
2443
2444 uevent = trace_ust_find_event_by_name(uchan->events, event->name);
2445 if (uevent == NULL) {
2446 uevent = trace_ust_create_event(event);
2447 if (uevent == NULL) {
2448 ret = LTTCOMM_FATAL;
2449 goto error;
2450 }
2451
2452 }
2453
2454 ret = ust_app_create_event_all(usess, uchan, uevent);
2455 if (ret < 0) {
2456 ret = LTTCOMM_UST_ENABLE_FAIL;
2457 goto error;
2458 }
2459
2460 /* Add ltt ust event to channel */
2461 rcu_read_lock();
2462 hashtable_add_unique(uchan->events, &uevent->node);
2463 rcu_read_unlock();
2464
2465 uevent->enabled = 1;
2466
2467 DBG3("UST ltt event %s added to channel %s", uevent->attr.name,
2468 uchan->name);
2469 break;
2470 }
2471 case LTTNG_DOMAIN_UST_EXEC_NAME:
2472 case LTTNG_DOMAIN_UST_PID:
2473 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2474 default:
2475 ret = LTTCOMM_NOT_IMPLEMENTED;
2476 goto error;
2477 }
2478
2479 ret = LTTCOMM_OK;
2480
2481 error:
2482 return ret;
2483 }
2484
2485 /*
2486 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2487 */
2488 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2489 char *channel_name, int event_type)
2490 {
2491 int ret;
2492 struct ltt_kernel_channel *kchan;
2493
2494 switch (domain) {
2495 case LTTNG_DOMAIN_KERNEL:
2496 kchan = trace_kernel_get_channel_by_name(channel_name,
2497 session->kernel_session);
2498 if (kchan == NULL) {
2499 /* This call will notify the kernel thread */
2500 ret = channel_kernel_create(session->kernel_session, NULL,
2501 kernel_poll_pipe[1]);
2502 if (ret != LTTCOMM_OK) {
2503 goto error;
2504 }
2505 }
2506
2507 /* Get the newly created kernel channel pointer */
2508 kchan = trace_kernel_get_channel_by_name(channel_name,
2509 session->kernel_session);
2510 if (kchan == NULL) {
2511 /* This sould not happen... */
2512 ret = LTTCOMM_FATAL;
2513 goto error;
2514 }
2515
2516 switch (event_type) {
2517 case LTTNG_KERNEL_SYSCALL:
2518 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2519 kchan, kernel_tracer_fd);
2520 break;
2521 case LTTNG_KERNEL_TRACEPOINT:
2522 /*
2523 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2524 * events already registered to the channel.
2525 */
2526 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2527 kchan, kernel_tracer_fd);
2528 break;
2529 case LTTNG_KERNEL_ALL:
2530 /* Enable syscalls and tracepoints */
2531 ret = event_kernel_enable_all(session->kernel_session,
2532 kchan, kernel_tracer_fd);
2533 break;
2534 default:
2535 ret = LTTCOMM_KERN_ENABLE_FAIL;
2536 goto error;
2537 }
2538 if (ret != LTTCOMM_OK) {
2539 goto error;
2540 }
2541
2542 kernel_wait_quiescent(kernel_tracer_fd);
2543 break;
2544 default:
2545 /* TODO: Userspace tracing */
2546 ret = LTTCOMM_NOT_IMPLEMENTED;
2547 goto error;
2548 }
2549
2550 ret = LTTCOMM_OK;
2551
2552 error:
2553 return ret;
2554 }
2555
2556 /*
2557 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2558 */
2559 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2560 {
2561 int ret;
2562 ssize_t nb_events = 0;
2563
2564 switch (domain) {
2565 case LTTNG_DOMAIN_KERNEL:
2566 nb_events = kernel_list_events(kernel_tracer_fd, events);
2567 if (nb_events < 0) {
2568 ret = LTTCOMM_KERN_LIST_FAIL;
2569 goto error;
2570 }
2571 break;
2572 case LTTNG_DOMAIN_UST:
2573 nb_events = ust_app_list_events(events);
2574 if (nb_events < 0) {
2575 ret = LTTCOMM_UST_LIST_FAIL;
2576 goto error;
2577 }
2578 break;
2579 default:
2580 ret = LTTCOMM_NOT_IMPLEMENTED;
2581 goto error;
2582 }
2583
2584 return nb_events;
2585
2586 error:
2587 /* Return negative value to differentiate return code */
2588 return -ret;
2589 }
2590
2591 /*
2592 * Command LTTNG_START_TRACE processed by the client thread.
2593 */
2594 static int cmd_start_trace(struct ltt_session *session)
2595 {
2596 int ret;
2597 struct ltt_kernel_session *ksession;
2598 struct ltt_ust_session *usess;
2599
2600 /* Short cut */
2601 ksession = session->kernel_session;
2602 usess = session->ust_session;
2603
2604 if (session->enabled)
2605 return LTTCOMM_UST_START_FAIL;
2606 session->enabled = 1;
2607
2608 /* Kernel tracing */
2609 if (ksession != NULL) {
2610 struct ltt_kernel_channel *kchan;
2611
2612 /* Open kernel metadata */
2613 if (ksession->metadata == NULL) {
2614 ret = kernel_open_metadata(ksession, ksession->trace_path);
2615 if (ret < 0) {
2616 ret = LTTCOMM_KERN_META_FAIL;
2617 goto error;
2618 }
2619 }
2620
2621 /* Open kernel metadata stream */
2622 if (ksession->metadata_stream_fd == 0) {
2623 ret = kernel_open_metadata_stream(ksession);
2624 if (ret < 0) {
2625 ERR("Kernel create metadata stream failed");
2626 ret = LTTCOMM_KERN_STREAM_FAIL;
2627 goto error;
2628 }
2629 }
2630
2631 /* For each channel */
2632 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2633 if (kchan->stream_count == 0) {
2634 ret = kernel_open_channel_stream(kchan);
2635 if (ret < 0) {
2636 ret = LTTCOMM_KERN_STREAM_FAIL;
2637 goto error;
2638 }
2639 /* Update the stream global counter */
2640 ksession->stream_count_global += ret;
2641 }
2642 }
2643
2644 /* Setup kernel consumer socket and send fds to it */
2645 ret = init_kernel_tracing(ksession);
2646 if (ret < 0) {
2647 ret = LTTCOMM_KERN_START_FAIL;
2648 goto error;
2649 }
2650
2651 /* This start the kernel tracing */
2652 ret = kernel_start_session(ksession);
2653 if (ret < 0) {
2654 ret = LTTCOMM_KERN_START_FAIL;
2655 goto error;
2656 }
2657
2658 /* Quiescent wait after starting trace */
2659 kernel_wait_quiescent(kernel_tracer_fd);
2660 }
2661
2662 /* Flag session that trace should start automatically */
2663 if (usess) {
2664 usess->start_trace = 1;
2665
2666 ret = ust_app_start_trace_all(usess);
2667 if (ret < 0) {
2668 ret = LTTCOMM_UST_START_FAIL;
2669 goto error;
2670 }
2671 }
2672
2673 ret = LTTCOMM_OK;
2674
2675 error:
2676 return ret;
2677 }
2678
2679 /*
2680 * Command LTTNG_STOP_TRACE processed by the client thread.
2681 */
2682 static int cmd_stop_trace(struct ltt_session *session)
2683 {
2684 int ret;
2685 struct ltt_kernel_channel *kchan;
2686 struct ltt_kernel_session *ksession;
2687 struct ltt_ust_session *usess;
2688
2689 /* Short cut */
2690 ksession = session->kernel_session;
2691 usess = session->ust_session;
2692
2693 if (!session->enabled)
2694 return LTTCOMM_UST_START_FAIL;
2695 session->enabled = 0;
2696
2697 /* Kernel tracer */
2698 if (ksession != NULL) {
2699 DBG("Stop kernel tracing");
2700
2701 /* Flush all buffers before stopping */
2702 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2703 if (ret < 0) {
2704 ERR("Kernel metadata flush failed");
2705 }
2706
2707 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2708 ret = kernel_flush_buffer(kchan);
2709 if (ret < 0) {
2710 ERR("Kernel flush buffer error");
2711 }
2712 }
2713
2714 ret = kernel_stop_session(ksession);
2715 if (ret < 0) {
2716 ret = LTTCOMM_KERN_STOP_FAIL;
2717 goto error;
2718 }
2719
2720 kernel_wait_quiescent(kernel_tracer_fd);
2721 }
2722
2723 /* Flag session that trace should start automatically */
2724 if (usess) {
2725 usess->start_trace = 0;
2726
2727 ret = ust_app_stop_trace_all(usess);
2728 if (ret < 0) {
2729 ret = LTTCOMM_UST_START_FAIL;
2730 goto error;
2731 }
2732 }
2733
2734 ret = LTTCOMM_OK;
2735
2736 error:
2737 return ret;
2738 }
2739
2740 /*
2741 * Command LTTNG_CREATE_SESSION processed by the client thread.
2742 */
2743 static int cmd_create_session(char *name, char *path)
2744 {
2745 int ret;
2746
2747 ret = session_create(name, path);
2748 if (ret != LTTCOMM_OK) {
2749 goto error;
2750 }
2751
2752 ret = LTTCOMM_OK;
2753
2754 error:
2755 return ret;
2756 }
2757
2758 /*
2759 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2760 */
2761 static int cmd_destroy_session(struct ltt_session *session, char *name)
2762 {
2763 int ret;
2764
2765 /* Clean kernel session teardown */
2766 teardown_kernel_session(session);
2767 /* UST session teardown */
2768 teardown_ust_session(session);
2769
2770 /*
2771 * Must notify the kernel thread here to update it's poll setin order
2772 * to remove the channel(s)' fd just destroyed.
2773 */
2774 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2775 if (ret < 0) {
2776 perror("write kernel poll pipe");
2777 }
2778
2779 ret = session_destroy(session);
2780
2781 return ret;
2782 }
2783
2784 /*
2785 * Command LTTNG_CALIBRATE processed by the client thread.
2786 */
2787 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2788 {
2789 int ret;
2790
2791 switch (domain) {
2792 case LTTNG_DOMAIN_KERNEL:
2793 {
2794 struct lttng_kernel_calibrate kcalibrate;
2795
2796 kcalibrate.type = calibrate->type;
2797 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2798 if (ret < 0) {
2799 ret = LTTCOMM_KERN_ENABLE_FAIL;
2800 goto error;
2801 }
2802 break;
2803 }
2804 default:
2805 /* TODO: Userspace tracing */
2806 ret = LTTCOMM_NOT_IMPLEMENTED;
2807 goto error;
2808 }
2809
2810 ret = LTTCOMM_OK;
2811
2812 error:
2813 return ret;
2814 }
2815
2816 /*
2817 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2818 */
2819 static int cmd_register_consumer(struct ltt_session *session, int domain,
2820 char *sock_path)
2821 {
2822 int ret, sock;
2823
2824 switch (domain) {
2825 case LTTNG_DOMAIN_KERNEL:
2826 /* Can't register a consumer if there is already one */
2827 if (session->kernel_session->consumer_fd != 0) {
2828 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2829 goto error;
2830 }
2831
2832 sock = lttcomm_connect_unix_sock(sock_path);
2833 if (sock < 0) {
2834 ret = LTTCOMM_CONNECT_FAIL;
2835 goto error;
2836 }
2837
2838 session->kernel_session->consumer_fd = sock;
2839 break;
2840 default:
2841 /* TODO: Userspace tracing */
2842 ret = LTTCOMM_NOT_IMPLEMENTED;
2843 goto error;
2844 }
2845
2846 ret = LTTCOMM_OK;
2847
2848 error:
2849 return ret;
2850 }
2851
2852 /*
2853 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2854 */
2855 static ssize_t cmd_list_domains(struct ltt_session *session,
2856 struct lttng_domain **domains)
2857 {
2858 int ret, index = 0;
2859 ssize_t nb_dom = 0;
2860
2861 if (session->kernel_session != NULL) {
2862 DBG3("Listing domains found kernel domain");
2863 nb_dom++;
2864 }
2865
2866 if (session->ust_session != NULL) {
2867 DBG3("Listing domains found UST global domain");
2868 nb_dom++;
2869 }
2870
2871 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2872 if (*domains == NULL) {
2873 ret = -LTTCOMM_FATAL;
2874 goto error;
2875 }
2876
2877 if (session->kernel_session != NULL) {
2878 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2879 index++;
2880 }
2881
2882 if (session->ust_session != NULL) {
2883 (*domains)[index].type = LTTNG_DOMAIN_UST;
2884 index++;
2885 }
2886
2887 return nb_dom;
2888
2889 error:
2890 return ret;
2891 }
2892
2893 /*
2894 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2895 */
2896 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
2897 struct lttng_channel **channels)
2898 {
2899 int ret;
2900 ssize_t nb_chan = 0;
2901
2902 switch (domain) {
2903 case LTTNG_DOMAIN_KERNEL:
2904 if (session->kernel_session != NULL) {
2905 nb_chan = session->kernel_session->channel_count;
2906 }
2907 DBG3("Number of kernel channels %zd", nb_chan);
2908 break;
2909 case LTTNG_DOMAIN_UST:
2910 if (session->ust_session != NULL) {
2911 nb_chan = hashtable_get_count(
2912 session->ust_session->domain_global.channels);
2913 }
2914 DBG3("Number of UST global channels %zd", nb_chan);
2915 break;
2916 default:
2917 *channels = NULL;
2918 ret = -LTTCOMM_NOT_IMPLEMENTED;
2919 goto error;
2920 }
2921
2922 if (nb_chan > 0) {
2923 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
2924 if (*channels == NULL) {
2925 ret = -LTTCOMM_FATAL;
2926 goto error;
2927 }
2928
2929 list_lttng_channels(domain, session, *channels);
2930 } else {
2931 *channels = NULL;
2932 }
2933
2934 return nb_chan;
2935
2936 error:
2937 return ret;
2938 }
2939
2940 /*
2941 * Command LTTNG_LIST_EVENTS processed by the client thread.
2942 */
2943 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
2944 char *channel_name, struct lttng_event **events)
2945 {
2946 int ret = 0;
2947 ssize_t nb_event = 0;
2948
2949 switch (domain) {
2950 case LTTNG_DOMAIN_KERNEL:
2951 if (session->kernel_session != NULL) {
2952 nb_event = list_lttng_kernel_events(channel_name,
2953 session->kernel_session, events);
2954 }
2955 break;
2956 case LTTNG_DOMAIN_UST:
2957 {
2958 if (session->ust_session != NULL) {
2959 nb_event = list_lttng_ust_global_events(channel_name,
2960 &session->ust_session->domain_global, events);
2961 }
2962 break;
2963 }
2964 default:
2965 ret = -LTTCOMM_NOT_IMPLEMENTED;
2966 goto error;
2967 }
2968
2969 ret = nb_event;
2970
2971 error:
2972 return ret;
2973 }
2974
2975 /*
2976 * Process the command requested by the lttng client within the command
2977 * context structure. This function make sure that the return structure (llm)
2978 * is set and ready for transmission before returning.
2979 *
2980 * Return any error encountered or 0 for success.
2981 */
2982 static int process_client_msg(struct command_ctx *cmd_ctx)
2983 {
2984 int ret = LTTCOMM_OK;
2985 int need_tracing_session = 1;
2986
2987 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
2988
2989 /*
2990 * Check for command that don't needs to allocate a returned payload. We do
2991 * this here so we don't have to make the call for no payload at each
2992 * command.
2993 */
2994 switch(cmd_ctx->lsm->cmd_type) {
2995 case LTTNG_LIST_SESSIONS:
2996 case LTTNG_LIST_TRACEPOINTS:
2997 case LTTNG_LIST_DOMAINS:
2998 case LTTNG_LIST_CHANNELS:
2999 case LTTNG_LIST_EVENTS:
3000 break;
3001 default:
3002 /* Setup lttng message with no payload */
3003 ret = setup_lttng_msg(cmd_ctx, 0);
3004 if (ret < 0) {
3005 /* This label does not try to unlock the session */
3006 goto init_setup_error;
3007 }
3008 }
3009
3010 /* Commands that DO NOT need a session. */
3011 switch (cmd_ctx->lsm->cmd_type) {
3012 case LTTNG_CALIBRATE:
3013 case LTTNG_CREATE_SESSION:
3014 case LTTNG_LIST_SESSIONS:
3015 case LTTNG_LIST_TRACEPOINTS:
3016 need_tracing_session = 0;
3017 break;
3018 default:
3019 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3020 session_lock_list();
3021 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3022 session_unlock_list();
3023 if (cmd_ctx->session == NULL) {
3024 if (cmd_ctx->lsm->session.name != NULL) {
3025 ret = LTTCOMM_SESS_NOT_FOUND;
3026 } else {
3027 /* If no session name specified */
3028 ret = LTTCOMM_SELECT_SESS;
3029 }
3030 goto error;
3031 } else {
3032 /* Acquire lock for the session */
3033 session_lock(cmd_ctx->session);
3034 }
3035 break;
3036 }
3037
3038 /*
3039 * Check domain type for specific "pre-action".
3040 */
3041 switch (cmd_ctx->lsm->domain.type) {
3042 case LTTNG_DOMAIN_KERNEL:
3043 /* Kernel tracer check */
3044 if (kernel_tracer_fd == 0) {
3045 /* Basically, load kernel tracer modules */
3046 init_kernel_tracer();
3047 if (kernel_tracer_fd == 0) {
3048 ret = LTTCOMM_KERN_NA;
3049 goto error;
3050 }
3051 }
3052
3053 /* Need a session for kernel command */
3054 if (need_tracing_session) {
3055 if (cmd_ctx->session->kernel_session == NULL) {
3056 ret = create_kernel_session(cmd_ctx->session);
3057 if (ret < 0) {
3058 ret = LTTCOMM_KERN_SESS_FAIL;
3059 goto error;
3060 }
3061 }
3062
3063 /* Start the kernel consumer daemon */
3064 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3065 if (kconsumer_data.pid == 0 &&
3066 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3067 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3068 ret = start_consumerd(&kconsumer_data);
3069 if (ret < 0) {
3070 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3071 goto error;
3072 }
3073 } else {
3074 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3075 }
3076 }
3077 break;
3078 case LTTNG_DOMAIN_UST:
3079 {
3080 if (need_tracing_session) {
3081 if (cmd_ctx->session->ust_session == NULL) {
3082 ret = create_ust_session(cmd_ctx->session,
3083 &cmd_ctx->lsm->domain);
3084 if (ret != LTTCOMM_OK) {
3085 goto error;
3086 }
3087 }
3088 /* Start the UST consumer daemons */
3089 /* 64-bit */
3090 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3091 if (consumerd64_bindir[0] != '\0' &&
3092 ustconsumer64_data.pid == 0 &&
3093 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3094 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3095 ret = start_consumerd(&ustconsumer64_data);
3096 if (ret < 0) {
3097 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3098 ust_consumerd64_fd = -EINVAL;
3099 goto error;
3100 }
3101
3102 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3103 } else {
3104 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3105 }
3106 /* 32-bit */
3107 if (consumerd32_bindir[0] != '\0' &&
3108 ustconsumer32_data.pid == 0 &&
3109 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3110 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3111 ret = start_consumerd(&ustconsumer32_data);
3112 if (ret < 0) {
3113 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3114 ust_consumerd32_fd = -EINVAL;
3115 goto error;
3116 }
3117 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3118 } else {
3119 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3120 }
3121 }
3122 break;
3123 }
3124 default:
3125 break;
3126 }
3127
3128 /* Process by command type */
3129 switch (cmd_ctx->lsm->cmd_type) {
3130 case LTTNG_ADD_CONTEXT:
3131 {
3132 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3133 cmd_ctx->lsm->u.context.channel_name,
3134 cmd_ctx->lsm->u.context.event_name,
3135 &cmd_ctx->lsm->u.context.ctx);
3136 break;
3137 }
3138 case LTTNG_DISABLE_CHANNEL:
3139 {
3140 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3141 cmd_ctx->lsm->u.disable.channel_name);
3142 break;
3143 }
3144 case LTTNG_DISABLE_EVENT:
3145 {
3146 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3147 cmd_ctx->lsm->u.disable.channel_name,
3148 cmd_ctx->lsm->u.disable.name);
3149 ret = LTTCOMM_OK;
3150 break;
3151 }
3152 case LTTNG_DISABLE_ALL_EVENT:
3153 {
3154 DBG("Disabling all events");
3155
3156 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3157 cmd_ctx->lsm->u.disable.channel_name);
3158 break;
3159 }
3160 case LTTNG_ENABLE_CHANNEL:
3161 {
3162 ret = cmd_enable_channel(cmd_ctx->session, &cmd_ctx->lsm->domain,
3163 &cmd_ctx->lsm->u.channel.chan);
3164 break;
3165 }
3166 case LTTNG_ENABLE_EVENT:
3167 {
3168 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3169 cmd_ctx->lsm->u.enable.channel_name,
3170 &cmd_ctx->lsm->u.enable.event);
3171 break;
3172 }
3173 case LTTNG_ENABLE_ALL_EVENT:
3174 {
3175 DBG("Enabling all events");
3176
3177 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3178 cmd_ctx->lsm->u.enable.channel_name,
3179 cmd_ctx->lsm->u.enable.event.type);
3180 break;
3181 }
3182 case LTTNG_LIST_TRACEPOINTS:
3183 {
3184 struct lttng_event *events;
3185 ssize_t nb_events;
3186
3187 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3188 if (nb_events < 0) {
3189 ret = -nb_events;
3190 goto error;
3191 }
3192
3193 /*
3194 * Setup lttng message with payload size set to the event list size in
3195 * bytes and then copy list into the llm payload.
3196 */
3197 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3198 if (ret < 0) {
3199 free(events);
3200 goto setup_error;
3201 }
3202
3203 /* Copy event list into message payload */
3204 memcpy(cmd_ctx->llm->payload, events,
3205 sizeof(struct lttng_event) * nb_events);
3206
3207 free(events);
3208
3209 ret = LTTCOMM_OK;
3210 break;
3211 }
3212 case LTTNG_START_TRACE:
3213 {
3214 ret = cmd_start_trace(cmd_ctx->session);
3215 break;
3216 }
3217 case LTTNG_STOP_TRACE:
3218 {
3219 ret = cmd_stop_trace(cmd_ctx->session);
3220 break;
3221 }
3222 case LTTNG_CREATE_SESSION:
3223 {
3224 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3225 cmd_ctx->lsm->session.path);
3226 break;
3227 }
3228 case LTTNG_DESTROY_SESSION:
3229 {
3230 ret = cmd_destroy_session(cmd_ctx->session,
3231 cmd_ctx->lsm->session.name);
3232 break;
3233 }
3234 case LTTNG_LIST_DOMAINS:
3235 {
3236 ssize_t nb_dom;
3237 struct lttng_domain *domains;
3238
3239 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3240 if (nb_dom < 0) {
3241 ret = -nb_dom;
3242 goto error;
3243 }
3244
3245 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3246 if (ret < 0) {
3247 goto setup_error;
3248 }
3249
3250 /* Copy event list into message payload */
3251 memcpy(cmd_ctx->llm->payload, domains,
3252 nb_dom * sizeof(struct lttng_domain));
3253
3254 free(domains);
3255
3256 ret = LTTCOMM_OK;
3257 break;
3258 }
3259 case LTTNG_LIST_CHANNELS:
3260 {
3261 size_t nb_chan;
3262 struct lttng_channel *channels;
3263
3264 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
3265 cmd_ctx->session, &channels);
3266 if (nb_chan < 0) {
3267 ret = -nb_chan;
3268 goto error;
3269 }
3270
3271 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3272 if (ret < 0) {
3273 goto setup_error;
3274 }
3275
3276 /* Copy event list into message payload */
3277 memcpy(cmd_ctx->llm->payload, channels,
3278 nb_chan * sizeof(struct lttng_channel));
3279
3280 free(channels);
3281
3282 ret = LTTCOMM_OK;
3283 break;
3284 }
3285 case LTTNG_LIST_EVENTS:
3286 {
3287 ssize_t nb_event;
3288 struct lttng_event *events = NULL;
3289
3290 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
3291 cmd_ctx->lsm->u.list.channel_name, &events);
3292 if (nb_event < 0) {
3293 ret = -nb_event;
3294 goto error;
3295 }
3296
3297 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3298 if (ret < 0) {
3299 goto setup_error;
3300 }
3301
3302 /* Copy event list into message payload */
3303 memcpy(cmd_ctx->llm->payload, events,
3304 nb_event * sizeof(struct lttng_event));
3305
3306 free(events);
3307
3308 ret = LTTCOMM_OK;
3309 break;
3310 }
3311 case LTTNG_LIST_SESSIONS:
3312 {
3313 session_lock_list();
3314
3315 if (session_list_ptr->count == 0) {
3316 ret = LTTCOMM_NO_SESSION;
3317 session_unlock_list();
3318 goto error;
3319 }
3320
3321 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) *
3322 session_list_ptr->count);
3323 if (ret < 0) {
3324 session_unlock_list();
3325 goto setup_error;
3326 }
3327
3328 /* Filled the session array */
3329 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
3330
3331 session_unlock_list();
3332
3333 ret = LTTCOMM_OK;
3334 break;
3335 }
3336 case LTTNG_CALIBRATE:
3337 {
3338 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3339 &cmd_ctx->lsm->u.calibrate);
3340 break;
3341 }
3342 case LTTNG_REGISTER_CONSUMER:
3343 {
3344 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3345 cmd_ctx->lsm->u.reg.path);
3346 break;
3347 }
3348 default:
3349 ret = LTTCOMM_UND;
3350 break;
3351 }
3352
3353 error:
3354 if (cmd_ctx->llm == NULL) {
3355 DBG("Missing llm structure. Allocating one.");
3356 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3357 goto setup_error;
3358 }
3359 }
3360 /* Set return code */
3361 cmd_ctx->llm->ret_code = ret;
3362 setup_error:
3363 if (cmd_ctx->session) {
3364 session_unlock(cmd_ctx->session);
3365 }
3366 init_setup_error:
3367 return ret;
3368 }
3369
3370 /*
3371 * This thread manage all clients request using the unix client socket for
3372 * communication.
3373 */
3374 static void *thread_manage_clients(void *data)
3375 {
3376 int sock = 0, ret, i, pollfd;
3377 uint32_t revents, nb_fd;
3378 struct command_ctx *cmd_ctx = NULL;
3379 struct lttng_poll_event events;
3380
3381 DBG("[thread] Manage client started");
3382
3383 rcu_register_thread();
3384
3385 ret = lttcomm_listen_unix_sock(client_sock);
3386 if (ret < 0) {
3387 goto error;
3388 }
3389
3390 /*
3391 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3392 * more will be added to this poll set.
3393 */
3394 ret = create_thread_poll_set(&events, 2);
3395 if (ret < 0) {
3396 goto error;
3397 }
3398
3399 /* Add the application registration socket */
3400 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3401 if (ret < 0) {
3402 goto error;
3403 }
3404
3405 /*
3406 * Notify parent pid that we are ready to accept command for client side.
3407 */
3408 if (opt_sig_parent) {
3409 kill(ppid, SIGCHLD);
3410 }
3411
3412 while (1) {
3413 DBG("Accepting client command ...");
3414
3415 nb_fd = LTTNG_POLL_GETNB(&events);
3416
3417 /* Inifinite blocking call, waiting for transmission */
3418 ret = lttng_poll_wait(&events, -1);
3419 if (ret < 0) {
3420 goto error;
3421 }
3422
3423 for (i = 0; i < nb_fd; i++) {
3424 /* Fetch once the poll data */
3425 revents = LTTNG_POLL_GETEV(&events, i);
3426 pollfd = LTTNG_POLL_GETFD(&events, i);
3427
3428 /* Thread quit pipe has been closed. Killing thread. */
3429 ret = check_thread_quit_pipe(pollfd, revents);
3430 if (ret) {
3431 goto error;
3432 }
3433
3434 /* Event on the registration socket */
3435 if (pollfd == client_sock) {
3436 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3437 ERR("Client socket poll error");
3438 goto error;
3439 }
3440 }
3441 }
3442
3443 DBG("Wait for client response");
3444
3445 sock = lttcomm_accept_unix_sock(client_sock);
3446 if (sock < 0) {
3447 goto error;
3448 }
3449
3450 /* Allocate context command to process the client request */
3451 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3452 if (cmd_ctx == NULL) {
3453 perror("zmalloc cmd_ctx");
3454 goto error;
3455 }
3456
3457 /* Allocate data buffer for reception */
3458 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3459 if (cmd_ctx->lsm == NULL) {
3460 perror("zmalloc cmd_ctx->lsm");
3461 goto error;
3462 }
3463
3464 cmd_ctx->llm = NULL;
3465 cmd_ctx->session = NULL;
3466
3467 /*
3468 * Data is received from the lttng client. The struct
3469 * lttcomm_session_msg (lsm) contains the command and data request of
3470 * the client.
3471 */
3472 DBG("Receiving data from client ...");
3473 ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm,
3474 sizeof(struct lttcomm_session_msg));
3475 if (ret <= 0) {
3476 DBG("Nothing recv() from client... continuing");
3477 close(sock);
3478 free(cmd_ctx);
3479 continue;
3480 }
3481
3482 // TODO: Validate cmd_ctx including sanity check for
3483 // security purpose.
3484
3485 rcu_thread_online();
3486 /*
3487 * This function dispatch the work to the kernel or userspace tracer
3488 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3489 * informations for the client. The command context struct contains
3490 * everything this function may needs.
3491 */
3492 ret = process_client_msg(cmd_ctx);
3493 rcu_thread_offline();
3494 if (ret < 0) {
3495 /*
3496 * TODO: Inform client somehow of the fatal error. At
3497 * this point, ret < 0 means that a zmalloc failed
3498 * (ENOMEM). Error detected but still accept command.
3499 */
3500 clean_command_ctx(&cmd_ctx);
3501 continue;
3502 }
3503
3504 DBG("Sending response (size: %d, retcode: %s)",
3505 cmd_ctx->lttng_msg_size,
3506 lttng_strerror(-cmd_ctx->llm->ret_code));
3507 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3508 if (ret < 0) {
3509 ERR("Failed to send data back to client");
3510 }
3511
3512 clean_command_ctx(&cmd_ctx);
3513
3514 /* End of transmission */
3515 close(sock);
3516 }
3517
3518 error:
3519 DBG("Client thread dying");
3520 unlink(client_unix_sock_path);
3521 close(client_sock);
3522 close(sock);
3523
3524 lttng_poll_clean(&events);
3525 clean_command_ctx(&cmd_ctx);
3526
3527 rcu_unregister_thread();
3528 return NULL;
3529 }
3530
3531
3532 /*
3533 * usage function on stderr
3534 */
3535 static void usage(void)
3536 {
3537 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3538 fprintf(stderr, " -h, --help Display this usage.\n");
3539 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3540 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3541 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3542 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3543 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
3544 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
3545 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
3546 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
3547 fprintf(stderr, " --ustconsumerd32 PATH Specify path for the 32-bit UST consumer daemon binary\n");
3548 fprintf(stderr, " --ustconsumerd64 PATH Specify path for the 64-bit UST consumer daemon binary\n");
3549 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3550 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3551 fprintf(stderr, " -V, --version Show version number.\n");
3552 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3553 fprintf(stderr, " -q, --quiet No output at all.\n");
3554 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3555 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3556 }
3557
3558 /*
3559 * daemon argument parsing
3560 */
3561 static int parse_args(int argc, char **argv)
3562 {
3563 int c;
3564
3565 static struct option long_options[] = {
3566 { "client-sock", 1, 0, 'c' },
3567 { "apps-sock", 1, 0, 'a' },
3568 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3569 { "kconsumerd-err-sock", 1, 0, 'E' },
3570 { "ustconsumerd64", 1, 0, 't' },
3571 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
3572 { "ustconsumerd64-err-sock", 1, 0, 'F' },
3573 { "ustconsumerd32", 1, 0, 'u' },
3574 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
3575 { "ustconsumerd32-err-sock", 1, 0, 'H' },
3576 { "daemonize", 0, 0, 'd' },
3577 { "sig-parent", 0, 0, 'S' },
3578 { "help", 0, 0, 'h' },
3579 { "group", 1, 0, 'g' },
3580 { "version", 0, 0, 'V' },
3581 { "quiet", 0, 0, 'q' },
3582 { "verbose", 0, 0, 'v' },
3583 { "verbose-consumer", 0, 0, 'Z' },
3584 { NULL, 0, 0, 0 }
3585 };
3586
3587 while (1) {
3588 int option_index = 0;
3589 c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:C:E:D:F:Z:u:t",
3590 long_options, &option_index);
3591 if (c == -1) {
3592 break;
3593 }
3594
3595 switch (c) {
3596 case 0:
3597 fprintf(stderr, "option %s", long_options[option_index].name);
3598 if (optarg) {
3599 fprintf(stderr, " with arg %s\n", optarg);
3600 }
3601 break;
3602 case 'c':
3603 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3604 break;
3605 case 'a':
3606 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3607 break;
3608 case 'd':
3609 opt_daemon = 1;
3610 break;
3611 case 'g':
3612 opt_tracing_group = optarg;
3613 break;
3614 case 'h':
3615 usage();
3616 exit(EXIT_FAILURE);
3617 case 'V':
3618 fprintf(stdout, "%s\n", VERSION);
3619 exit(EXIT_SUCCESS);
3620 case 'S':
3621 opt_sig_parent = 1;
3622 break;
3623 case 'E':
3624 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3625 break;
3626 case 'C':
3627 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3628 break;
3629 case 'F':
3630 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3631 break;
3632 case 'D':
3633 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3634 break;
3635 case 'H':
3636 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3637 break;
3638 case 'G':
3639 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3640 break;
3641 case 'q':
3642 opt_quiet = 1;
3643 break;
3644 case 'v':
3645 /* Verbose level can increase using multiple -v */
3646 opt_verbose += 1;
3647 break;
3648 case 'Z':
3649 opt_verbose_consumer += 1;
3650 break;
3651 case 'u':
3652 consumerd32_bindir = optarg;
3653 break;
3654 case 't':
3655 consumerd64_bindir = optarg;
3656 break;
3657 default:
3658 /* Unknown option or other error.
3659 * Error is printed by getopt, just return */
3660 return -1;
3661 }
3662 }
3663
3664 return 0;
3665 }
3666
3667 /*
3668 * Creates the two needed socket by the daemon.
3669 * apps_sock - The communication socket for all UST apps.
3670 * client_sock - The communication of the cli tool (lttng).
3671 */
3672 static int init_daemon_socket(void)
3673 {
3674 int ret = 0;
3675 mode_t old_umask;
3676
3677 old_umask = umask(0);
3678
3679 /* Create client tool unix socket */
3680 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3681 if (client_sock < 0) {
3682 ERR("Create unix sock failed: %s", client_unix_sock_path);
3683 ret = -1;
3684 goto end;
3685 }
3686
3687 /* File permission MUST be 660 */
3688 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3689 if (ret < 0) {
3690 ERR("Set file permissions failed: %s", client_unix_sock_path);
3691 perror("chmod");
3692 goto end;
3693 }
3694
3695 /* Create the application unix socket */
3696 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3697 if (apps_sock < 0) {
3698 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3699 ret = -1;
3700 goto end;
3701 }
3702
3703 /* File permission MUST be 666 */
3704 ret = chmod(apps_unix_sock_path,
3705 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3706 if (ret < 0) {
3707 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3708 perror("chmod");
3709 goto end;
3710 }
3711
3712 end:
3713 umask(old_umask);
3714 return ret;
3715 }
3716
3717 /*
3718 * Check if the global socket is available, and if a daemon is answering at the
3719 * other side. If yes, error is returned.
3720 */
3721 static int check_existing_daemon(void)
3722 {
3723 if (access(client_unix_sock_path, F_OK) < 0 &&
3724 access(apps_unix_sock_path, F_OK) < 0) {
3725 return 0;
3726 }
3727
3728 /* Is there anybody out there ? */
3729 if (lttng_session_daemon_alive()) {
3730 return -EEXIST;
3731 } else {
3732 return 0;
3733 }
3734 }
3735
3736 /*
3737 * Set the tracing group gid onto the client socket.
3738 *
3739 * Race window between mkdir and chown is OK because we are going from more
3740 * permissive (root.root) to les permissive (root.tracing).
3741 */
3742 static int set_permissions(void)
3743 {
3744 int ret;
3745 gid_t gid;
3746
3747 gid = allowed_group();
3748 if (gid < 0) {
3749 if (is_root) {
3750 WARN("No tracing group detected");
3751 ret = 0;
3752 } else {
3753 ERR("Missing tracing group. Aborting execution.");
3754 ret = -1;
3755 }
3756 goto end;
3757 }
3758
3759 /* Set lttng run dir */
3760 ret = chown(LTTNG_RUNDIR, 0, gid);
3761 if (ret < 0) {
3762 ERR("Unable to set group on " LTTNG_RUNDIR);
3763 perror("chown");
3764 }
3765
3766 /* lttng client socket path */
3767 ret = chown(client_unix_sock_path, 0, gid);
3768 if (ret < 0) {
3769 ERR("Unable to set group on %s", client_unix_sock_path);
3770 perror("chown");
3771 }
3772
3773 /* kconsumer error socket path */
3774 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
3775 if (ret < 0) {
3776 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
3777 perror("chown");
3778 }
3779
3780 /* 64-bit ustconsumer error socket path */
3781 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
3782 if (ret < 0) {
3783 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
3784 perror("chown");
3785 }
3786
3787 /* 32-bit ustconsumer compat32 error socket path */
3788 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
3789 if (ret < 0) {
3790 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
3791 perror("chown");
3792 }
3793
3794 DBG("All permissions are set");
3795
3796 end:
3797 return ret;
3798 }
3799
3800 /*
3801 * Create the pipe used to wake up the kernel thread.
3802 */
3803 static int create_kernel_poll_pipe(void)
3804 {
3805 return pipe2(kernel_poll_pipe, O_CLOEXEC);
3806 }
3807
3808 /*
3809 * Create the application command pipe to wake thread_manage_apps.
3810 */
3811 static int create_apps_cmd_pipe(void)
3812 {
3813 return pipe2(apps_cmd_pipe, O_CLOEXEC);
3814 }
3815
3816 /*
3817 * Create the lttng run directory needed for all global sockets and pipe.
3818 */
3819 static int create_lttng_rundir(void)
3820 {
3821 int ret;
3822
3823 ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG );
3824 if (ret < 0) {
3825 if (errno != EEXIST) {
3826 ERR("Unable to create " LTTNG_RUNDIR);
3827 goto error;
3828 } else {
3829 ret = 0;
3830 }
3831 }
3832
3833 error:
3834 return ret;
3835 }
3836
3837 /*
3838 * Setup sockets and directory needed by the kconsumerd communication with the
3839 * session daemon.
3840 */
3841 static int set_consumer_sockets(struct consumer_data *consumer_data)
3842 {
3843 int ret;
3844 const char *path;
3845
3846 switch (consumer_data->type) {
3847 case LTTNG_CONSUMER_KERNEL:
3848 path = KCONSUMERD_PATH;
3849 break;
3850 case LTTNG_CONSUMER64_UST:
3851 path = USTCONSUMERD64_PATH;
3852 break;
3853 case LTTNG_CONSUMER32_UST:
3854 path = USTCONSUMERD32_PATH;
3855 break;
3856 default:
3857 ERR("Consumer type unknown");
3858 ret = -EINVAL;
3859 goto error;
3860 }
3861
3862 ret = mkdir(path, S_IRWXU | S_IRWXG);
3863 if (ret < 0) {
3864 if (errno != EEXIST) {
3865 ERR("Failed to create %s", path);
3866 goto error;
3867 }
3868 ret = 0;
3869 }
3870
3871 /* Create the kconsumerd error unix socket */
3872 consumer_data->err_sock =
3873 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
3874 if (consumer_data->err_sock < 0) {
3875 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
3876 ret = -1;
3877 goto error;
3878 }
3879
3880 /* File permission MUST be 660 */
3881 ret = chmod(consumer_data->err_unix_sock_path,
3882 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3883 if (ret < 0) {
3884 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
3885 perror("chmod");
3886 goto error;
3887 }
3888
3889 error:
3890 return ret;
3891 }
3892
3893 /*
3894 * Signal handler for the daemon
3895 *
3896 * Simply stop all worker threads, leaving main() return gracefully after
3897 * joining all threads and calling cleanup().
3898 */
3899 static void sighandler(int sig)
3900 {
3901 switch (sig) {
3902 case SIGPIPE:
3903 DBG("SIGPIPE catched");
3904 return;
3905 case SIGINT:
3906 DBG("SIGINT catched");
3907 stop_threads();
3908 break;
3909 case SIGTERM:
3910 DBG("SIGTERM catched");
3911 stop_threads();
3912 break;
3913 default:
3914 break;
3915 }
3916 }
3917
3918 /*
3919 * Setup signal handler for :
3920 * SIGINT, SIGTERM, SIGPIPE
3921 */
3922 static int set_signal_handler(void)
3923 {
3924 int ret = 0;
3925 struct sigaction sa;
3926 sigset_t sigset;
3927
3928 if ((ret = sigemptyset(&sigset)) < 0) {
3929 perror("sigemptyset");
3930 return ret;
3931 }
3932
3933 sa.sa_handler = sighandler;
3934 sa.sa_mask = sigset;
3935 sa.sa_flags = 0;
3936 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
3937 perror("sigaction");
3938 return ret;
3939 }
3940
3941 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
3942 perror("sigaction");
3943 return ret;
3944 }
3945
3946 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
3947 perror("sigaction");
3948 return ret;
3949 }
3950
3951 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3952
3953 return ret;
3954 }
3955
3956 /*
3957 * Set open files limit to unlimited. This daemon can open a large number of
3958 * file descriptors in order to consumer multiple kernel traces.
3959 */
3960 static void set_ulimit(void)
3961 {
3962 int ret;
3963 struct rlimit lim;
3964
3965 /* The kernel does not allowed an infinite limit for open files */
3966 lim.rlim_cur = 65535;
3967 lim.rlim_max = 65535;
3968
3969 ret = setrlimit(RLIMIT_NOFILE, &lim);
3970 if (ret < 0) {
3971 perror("failed to set open files limit");
3972 }
3973 }
3974
3975 /*
3976 * main
3977 */
3978 int main(int argc, char **argv)
3979 {
3980 int ret = 0;
3981 void *status;
3982 const char *home_path;
3983
3984 rcu_register_thread();
3985
3986 /* Create thread quit pipe */
3987 if ((ret = init_thread_quit_pipe()) < 0) {
3988 goto error;
3989 }
3990
3991 setup_consumerd_path();
3992
3993 /* Parse arguments */
3994 progname = argv[0];
3995 if ((ret = parse_args(argc, argv) < 0)) {
3996 goto error;
3997 }
3998
3999 /* Daemonize */
4000 if (opt_daemon) {
4001 ret = daemon(0, 0);
4002 if (ret < 0) {
4003 perror("daemon");
4004 goto error;
4005 }
4006 }
4007
4008 /* Check if daemon is UID = 0 */
4009 is_root = !getuid();
4010
4011 if (is_root) {
4012 ret = create_lttng_rundir();
4013 if (ret < 0) {
4014 goto error;
4015 }
4016
4017 if (strlen(apps_unix_sock_path) == 0) {
4018 snprintf(apps_unix_sock_path, PATH_MAX,
4019 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
4020 }
4021
4022 if (strlen(client_unix_sock_path) == 0) {
4023 snprintf(client_unix_sock_path, PATH_MAX,
4024 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
4025 }
4026
4027 /* Set global SHM for ust */
4028 if (strlen(wait_shm_path) == 0) {
4029 snprintf(wait_shm_path, PATH_MAX,
4030 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
4031 }
4032 } else {
4033 home_path = get_home_dir();
4034 if (home_path == NULL) {
4035 /* TODO: Add --socket PATH option */
4036 ERR("Can't get HOME directory for sockets creation.");
4037 ret = -EPERM;
4038 goto error;
4039 }
4040
4041 if (strlen(apps_unix_sock_path) == 0) {
4042 snprintf(apps_unix_sock_path, PATH_MAX,
4043 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
4044 }
4045
4046 /* Set the cli tool unix socket path */
4047 if (strlen(client_unix_sock_path) == 0) {
4048 snprintf(client_unix_sock_path, PATH_MAX,
4049 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
4050 }
4051
4052 /* Set global SHM for ust */
4053 if (strlen(wait_shm_path) == 0) {
4054 snprintf(wait_shm_path, PATH_MAX,
4055 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
4056 }
4057 }
4058
4059 DBG("Client socket path %s", client_unix_sock_path);
4060 DBG("Application socket path %s", apps_unix_sock_path);
4061
4062 /*
4063 * See if daemon already exist.
4064 */
4065 if ((ret = check_existing_daemon()) < 0) {
4066 ERR("Already running daemon.\n");
4067 /*
4068 * We do not goto exit because we must not cleanup()
4069 * because a daemon is already running.
4070 */
4071 goto error;
4072 }
4073
4074 /* After this point, we can safely call cleanup() with "goto exit" */
4075
4076 /*
4077 * These actions must be executed as root. We do that *after* setting up
4078 * the sockets path because we MUST make the check for another daemon using
4079 * those paths *before* trying to set the kernel consumer sockets and init
4080 * kernel tracer.
4081 */
4082 if (is_root) {
4083 ret = set_consumer_sockets(&kconsumer_data);
4084 if (ret < 0) {
4085 goto exit;
4086 }
4087
4088 ret = set_consumer_sockets(&ustconsumer64_data);
4089 if (ret < 0) {
4090 goto exit;
4091 }
4092
4093 ret = set_consumer_sockets(&ustconsumer32_data);
4094 if (ret < 0) {
4095 goto exit;
4096 }
4097
4098 /* Setup kernel tracer */
4099 init_kernel_tracer();
4100
4101 /* Set ulimit for open files */
4102 set_ulimit();
4103 }
4104
4105 if ((ret = set_signal_handler()) < 0) {
4106 goto exit;
4107 }
4108
4109 /* Setup the needed unix socket */
4110 if ((ret = init_daemon_socket()) < 0) {
4111 goto exit;
4112 }
4113
4114 /* Set credentials to socket */
4115 if (is_root && ((ret = set_permissions()) < 0)) {
4116 goto exit;
4117 }
4118
4119 /* Get parent pid if -S, --sig-parent is specified. */
4120 if (opt_sig_parent) {
4121 ppid = getppid();
4122 }
4123
4124 /* Setup the kernel pipe for waking up the kernel thread */
4125 if ((ret = create_kernel_poll_pipe()) < 0) {
4126 goto exit;
4127 }
4128
4129 /* Setup the thread apps communication pipe. */
4130 if ((ret = create_apps_cmd_pipe()) < 0) {
4131 goto exit;
4132 }
4133
4134 /* Init UST command queue. */
4135 cds_wfq_init(&ust_cmd_queue.queue);
4136
4137 /* Init UST app hash table */
4138 ust_app_ht_alloc();
4139
4140 /*
4141 * Get session list pointer. This pointer MUST NOT be free(). This list is
4142 * statically declared in session.c
4143 */
4144 session_list_ptr = session_get_list();
4145
4146 /* Set up max poll set size */
4147 lttng_poll_set_max_size();
4148
4149 /* Create thread to manage the client socket */
4150 ret = pthread_create(&client_thread, NULL,
4151 thread_manage_clients, (void *) NULL);
4152 if (ret != 0) {
4153 perror("pthread_create clients");
4154 goto exit_client;
4155 }
4156
4157 /* Create thread to dispatch registration */
4158 ret = pthread_create(&dispatch_thread, NULL,
4159 thread_dispatch_ust_registration, (void *) NULL);
4160 if (ret != 0) {
4161 perror("pthread_create dispatch");
4162 goto exit_dispatch;
4163 }
4164
4165 /* Create thread to manage application registration. */
4166 ret = pthread_create(&reg_apps_thread, NULL,
4167 thread_registration_apps, (void *) NULL);
4168 if (ret != 0) {
4169 perror("pthread_create registration");
4170 goto exit_reg_apps;
4171 }
4172
4173 /* Create thread to manage application socket */
4174 ret = pthread_create(&apps_thread, NULL,
4175 thread_manage_apps, (void *) NULL);
4176 if (ret != 0) {
4177 perror("pthread_create apps");
4178 goto exit_apps;
4179 }
4180
4181 /* Create kernel thread to manage kernel event */
4182 ret = pthread_create(&kernel_thread, NULL,
4183 thread_manage_kernel, (void *) NULL);
4184 if (ret != 0) {
4185 perror("pthread_create kernel");
4186 goto exit_kernel;
4187 }
4188
4189 ret = pthread_join(kernel_thread, &status);
4190 if (ret != 0) {
4191 perror("pthread_join");
4192 goto error; /* join error, exit without cleanup */
4193 }
4194
4195 exit_kernel:
4196 ret = pthread_join(apps_thread, &status);
4197 if (ret != 0) {
4198 perror("pthread_join");
4199 goto error; /* join error, exit without cleanup */
4200 }
4201
4202 exit_apps:
4203 ret = pthread_join(reg_apps_thread, &status);
4204 if (ret != 0) {
4205 perror("pthread_join");
4206 goto error; /* join error, exit without cleanup */
4207 }
4208
4209 exit_reg_apps:
4210 ret = pthread_join(dispatch_thread, &status);
4211 if (ret != 0) {
4212 perror("pthread_join");
4213 goto error; /* join error, exit without cleanup */
4214 }
4215
4216 exit_dispatch:
4217 ret = pthread_join(client_thread, &status);
4218 if (ret != 0) {
4219 perror("pthread_join");
4220 goto error; /* join error, exit without cleanup */
4221 }
4222
4223 ret = join_consumer_thread(&kconsumer_data);
4224 if (ret != 0) {
4225 perror("join_consumer");
4226 goto error; /* join error, exit without cleanup */
4227 }
4228
4229 exit_client:
4230 exit:
4231 /*
4232 * cleanup() is called when no other thread is running.
4233 */
4234 rcu_thread_online();
4235 cleanup();
4236 rcu_thread_offline();
4237 rcu_unregister_thread();
4238 if (!ret)
4239 exit(EXIT_SUCCESS);
4240 error:
4241 exit(EXIT_FAILURE);
4242 }
LTTng 2.0 tools and control repository
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