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4bb7240378161540cb4573e4a3fc91e076dbdbae
[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 channels[i].enabled = uchan->enabled;
1926 i++;
1927 }
1928 break;
1929 }
1930 default:
1931 break;
1932 }
1933 }
1934
1935 /*
1936 * Create a list of ust global domain events.
1937 */
1938 static int list_lttng_ust_global_events(char *channel_name,
1939 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
1940 {
1941 int i = 0, ret = 0;
1942 unsigned int nb_event = 0;
1943 struct cds_lfht_iter iter;
1944 struct ltt_ust_channel *uchan;
1945 struct ltt_ust_event *uevent;
1946 struct lttng_event *tmp;
1947
1948 DBG("Listing UST global events for channel %s", channel_name);
1949
1950 rcu_read_lock();
1951
1952 /* Count events in all channels */
1953 cds_lfht_for_each_entry(ust_global->channels, &iter, uchan, node) {
1954 nb_event += hashtable_get_count(uchan->events);
1955 }
1956
1957 if (nb_event == 0) {
1958 ret = nb_event;
1959 goto error;
1960 }
1961
1962 DBG3("Listing UST global %d events", nb_event);
1963
1964 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
1965 if (tmp == NULL) {
1966 ret = -LTTCOMM_FATAL;
1967 goto error;
1968 }
1969
1970 cds_lfht_for_each_entry(ust_global->channels, &iter, uchan, node) {
1971 cds_lfht_for_each_entry(uchan->events, &iter, uevent, node) {
1972 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
1973 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
1974 tmp[i].enabled = uevent->enabled;
1975 switch (uevent->attr.instrumentation) {
1976 case LTTNG_UST_TRACEPOINT:
1977 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
1978 break;
1979 case LTTNG_UST_PROBE:
1980 tmp[i].type = LTTNG_EVENT_PROBE;
1981 break;
1982 case LTTNG_UST_FUNCTION:
1983 tmp[i].type = LTTNG_EVENT_FUNCTION;
1984 break;
1985 }
1986 i++;
1987 }
1988 }
1989
1990 ret = nb_event;
1991 *events = tmp;
1992
1993 error:
1994 rcu_read_unlock();
1995 return ret;
1996 }
1997
1998 /*
1999 * Fill lttng_event array of all kernel events in the channel.
2000 */
2001 static int list_lttng_kernel_events(char *channel_name,
2002 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2003 {
2004 int i = 0, ret;
2005 unsigned int nb_event;
2006 struct ltt_kernel_event *event;
2007 struct ltt_kernel_channel *kchan;
2008
2009 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2010 if (kchan == NULL) {
2011 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2012 goto error;
2013 }
2014
2015 nb_event = kchan->event_count;
2016
2017 DBG("Listing events for channel %s", kchan->channel->name);
2018
2019 if (nb_event == 0) {
2020 ret = nb_event;
2021 goto error;
2022 }
2023
2024 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2025 if (*events == NULL) {
2026 ret = LTTCOMM_FATAL;
2027 goto error;
2028 }
2029
2030 /* Kernel channels */
2031 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2032 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2033 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2034 (*events)[i].enabled = event->enabled;
2035 switch (event->event->instrumentation) {
2036 case LTTNG_KERNEL_TRACEPOINT:
2037 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2038 break;
2039 case LTTNG_KERNEL_KPROBE:
2040 case LTTNG_KERNEL_KRETPROBE:
2041 (*events)[i].type = LTTNG_EVENT_PROBE;
2042 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2043 sizeof(struct lttng_kernel_kprobe));
2044 break;
2045 case LTTNG_KERNEL_FUNCTION:
2046 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2047 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2048 sizeof(struct lttng_kernel_function));
2049 break;
2050 case LTTNG_KERNEL_NOOP:
2051 (*events)[i].type = LTTNG_EVENT_NOOP;
2052 break;
2053 case LTTNG_KERNEL_SYSCALL:
2054 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2055 break;
2056 case LTTNG_KERNEL_ALL:
2057 assert(0);
2058 break;
2059 }
2060 i++;
2061 }
2062
2063 return nb_event;
2064
2065 error:
2066 return ret;
2067 }
2068
2069 /*
2070 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2071 */
2072 static int cmd_disable_channel(struct ltt_session *session,
2073 int domain, char *channel_name)
2074 {
2075 int ret;
2076 struct ltt_ust_session *usess;
2077
2078 usess = session->ust_session;
2079
2080 switch (domain) {
2081 case LTTNG_DOMAIN_KERNEL:
2082 {
2083 ret = channel_kernel_disable(session->kernel_session,
2084 channel_name);
2085 if (ret != LTTCOMM_OK) {
2086 goto error;
2087 }
2088
2089 kernel_wait_quiescent(kernel_tracer_fd);
2090 break;
2091 }
2092 case LTTNG_DOMAIN_UST:
2093 {
2094 struct ltt_ust_channel *uchan;
2095
2096 /* Get channel in global UST domain HT */
2097 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2098 channel_name);
2099 if (uchan == NULL) {
2100 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2101 goto error;
2102 }
2103
2104 ret = ust_app_disable_channel_all(usess, uchan);
2105 if (ret < 0) {
2106 ret = LTTCOMM_UST_DISABLE_FAIL;
2107 goto error;
2108 }
2109
2110 uchan->enabled = 0;
2111
2112 break;
2113 }
2114 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2115 case LTTNG_DOMAIN_UST_EXEC_NAME:
2116 case LTTNG_DOMAIN_UST_PID:
2117 ret = LTTCOMM_NOT_IMPLEMENTED;
2118 goto error;
2119 default:
2120 ret = LTTCOMM_UNKNOWN_DOMAIN;
2121 goto error;
2122 }
2123
2124 ret = LTTCOMM_OK;
2125
2126 error:
2127 return ret;
2128 }
2129
2130 /*
2131 * Copy channel from attributes and set it in the application channel list.
2132 */
2133 /*
2134 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
2135 struct lttng_channel *attr, struct ust_app *app)
2136 {
2137 int ret;
2138 struct ltt_ust_channel *uchan, *new_chan;
2139
2140 uchan = trace_ust_get_channel_by_key(usess->channels, attr->name);
2141 if (uchan == NULL) {
2142 ret = LTTCOMM_FATAL;
2143 goto error;
2144 }
2145
2146 new_chan = trace_ust_create_channel(attr, usess->path);
2147 if (new_chan == NULL) {
2148 PERROR("malloc ltt_ust_channel");
2149 ret = LTTCOMM_FATAL;
2150 goto error;
2151 }
2152
2153 ret = channel_ust_copy(new_chan, uchan);
2154 if (ret < 0) {
2155 ret = LTTCOMM_FATAL;
2156 goto error;
2157 }
2158
2159 error:
2160 return ret;
2161 }
2162 */
2163
2164 /*
2165 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2166 */
2167 static int cmd_enable_channel(struct ltt_session *session,
2168 int domain, struct lttng_channel *attr)
2169 {
2170 int ret;
2171 struct ltt_ust_session *usess = session->ust_session;
2172
2173 DBG("Enabling channel %s for session %s", attr->name, session->name);
2174
2175 switch (domain) {
2176 case LTTNG_DOMAIN_KERNEL:
2177 {
2178 struct ltt_kernel_channel *kchan;
2179
2180 kchan = trace_kernel_get_channel_by_name(attr->name,
2181 session->kernel_session);
2182 if (kchan == NULL) {
2183 ret = channel_kernel_create(session->kernel_session,
2184 attr, kernel_poll_pipe[1]);
2185 } else {
2186 ret = channel_kernel_enable(session->kernel_session, kchan);
2187 }
2188
2189 if (ret != LTTCOMM_OK) {
2190 goto error;
2191 }
2192
2193 kernel_wait_quiescent(kernel_tracer_fd);
2194 break;
2195 }
2196 case LTTNG_DOMAIN_UST:
2197 {
2198 struct ltt_ust_channel *uchan;
2199
2200 DBG2("Enabling channel for LTTNG_DOMAIN_UST");
2201
2202 /* Get channel in global UST domain HT */
2203 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2204 attr->name);
2205 if (uchan == NULL) {
2206 uchan = trace_ust_create_channel(attr, usess->pathname);
2207 if (uchan == NULL) {
2208 ret = LTTCOMM_UST_CHAN_FAIL;
2209 goto error;
2210 }
2211
2212 rcu_read_lock();
2213 hashtable_add_unique(usess->domain_global.channels, &uchan->node);
2214 rcu_read_unlock();
2215 DBG2("UST channel %s added to global domain HT", attr->name);
2216
2217 /* Add channel to all registered applications */
2218 ret = ust_app_create_channel_all(usess, uchan);
2219 if (ret != 0) {
2220 ret = LTTCOMM_UST_CHAN_FAIL;
2221 goto error;
2222 }
2223 } else {
2224 /* If already enabled, everything is OK */
2225 if (uchan->enabled) {
2226 ret = LTTCOMM_OK;
2227 goto error;
2228 }
2229
2230 ret = ust_app_enable_channel_all(usess, uchan);
2231 if (ret < 0) {
2232 ret = LTTCOMM_UST_ENABLE_FAIL;
2233 goto error;
2234 }
2235 }
2236
2237 uchan->enabled = 1;
2238
2239 break;
2240 }
2241 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2242 case LTTNG_DOMAIN_UST_EXEC_NAME:
2243 case LTTNG_DOMAIN_UST_PID:
2244 ret = LTTCOMM_NOT_IMPLEMENTED;
2245 goto error;
2246 default:
2247 ret = LTTCOMM_UNKNOWN_DOMAIN;
2248 goto error;
2249 }
2250
2251 ret = LTTCOMM_OK;
2252
2253 error:
2254 return ret;
2255 }
2256
2257 /*
2258 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2259 */
2260 static int cmd_disable_event(struct ltt_session *session, int domain,
2261 char *channel_name, char *event_name)
2262 {
2263 int ret;
2264
2265 switch (domain) {
2266 case LTTNG_DOMAIN_KERNEL:
2267 {
2268 struct ltt_kernel_channel *kchan;
2269
2270 kchan = trace_kernel_get_channel_by_name(channel_name,
2271 session->kernel_session);
2272 if (kchan == NULL) {
2273 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2274 goto error;
2275 }
2276
2277 ret = event_kernel_disable_tracepoint(session->kernel_session, kchan, event_name);
2278 if (ret != LTTCOMM_OK) {
2279 goto error;
2280 }
2281
2282 kernel_wait_quiescent(kernel_tracer_fd);
2283 break;
2284 }
2285 case LTTNG_DOMAIN_UST:
2286 case LTTNG_DOMAIN_UST_EXEC_NAME:
2287 case LTTNG_DOMAIN_UST_PID:
2288 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2289 default:
2290 /* TODO: Other UST domains */
2291 ret = LTTCOMM_NOT_IMPLEMENTED;
2292 goto error;
2293 }
2294
2295 ret = LTTCOMM_OK;
2296
2297 error:
2298 return ret;
2299 }
2300
2301 /*
2302 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2303 */
2304 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2305 char *channel_name)
2306 {
2307 int ret;
2308 struct ltt_kernel_channel *kchan;
2309
2310 switch (domain) {
2311 case LTTNG_DOMAIN_KERNEL:
2312 kchan = trace_kernel_get_channel_by_name(channel_name,
2313 session->kernel_session);
2314 if (kchan == NULL) {
2315 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2316 goto error;
2317 }
2318
2319 ret = event_kernel_disable_all(session->kernel_session, kchan);
2320 if (ret != LTTCOMM_OK) {
2321 goto error;
2322 }
2323
2324 kernel_wait_quiescent(kernel_tracer_fd);
2325 break;
2326 default:
2327 /* TODO: Userspace tracing */
2328 ret = LTTCOMM_NOT_IMPLEMENTED;
2329 goto error;
2330 }
2331
2332 ret = LTTCOMM_OK;
2333
2334 error:
2335 return ret;
2336 }
2337
2338 /*
2339 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2340 */
2341 static int cmd_add_context(struct ltt_session *session, int domain,
2342 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2343 {
2344 int ret;
2345
2346 switch (domain) {
2347 case LTTNG_DOMAIN_KERNEL:
2348 /* Add kernel context to kernel tracer */
2349 ret = context_kernel_add(session->kernel_session, ctx,
2350 event_name, channel_name);
2351 if (ret != LTTCOMM_OK) {
2352 goto error;
2353 }
2354 break;
2355 case LTTNG_DOMAIN_UST:
2356 {
2357 /*
2358 struct ltt_ust_session *usess;
2359
2360 cds_list_for_each_entry(usess, &session->ust_session_list.head, list) {
2361 ret = context_ust_add(usess, ctx,
2362 event_name, channel_name, domain);
2363 if (ret != LTTCOMM_OK) {
2364 goto error;
2365 }
2366 }
2367 break;
2368 */
2369 }
2370 default:
2371 /* TODO: UST other domains */
2372 ret = LTTCOMM_NOT_IMPLEMENTED;
2373 goto error;
2374 }
2375
2376 ret = LTTCOMM_OK;
2377
2378 error:
2379 return ret;
2380 }
2381
2382 /*
2383 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2384 */
2385 static int cmd_enable_event(struct ltt_session *session, int domain,
2386 char *channel_name, struct lttng_event *event)
2387 {
2388 int ret;
2389 struct lttng_channel *attr;
2390 struct ltt_ust_session *usess = session->ust_session;
2391
2392 switch (domain) {
2393 case LTTNG_DOMAIN_KERNEL:
2394 {
2395 struct ltt_kernel_channel *kchan;
2396
2397 kchan = trace_kernel_get_channel_by_name(channel_name,
2398 session->kernel_session);
2399 if (kchan == NULL) {
2400 attr = channel_new_default_attr(domain);
2401 if (attr == NULL) {
2402 ret = LTTCOMM_FATAL;
2403 goto error;
2404 }
2405 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2406
2407 /* This call will notify the kernel thread */
2408 ret = channel_kernel_create(session->kernel_session,
2409 attr, kernel_poll_pipe[1]);
2410 if (ret != LTTCOMM_OK) {
2411 goto error;
2412 }
2413 }
2414
2415 /* Get the newly created kernel channel pointer */
2416 kchan = trace_kernel_get_channel_by_name(channel_name,
2417 session->kernel_session);
2418 if (kchan == NULL) {
2419 /* This sould not happen... */
2420 ret = LTTCOMM_FATAL;
2421 goto error;
2422 }
2423
2424 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2425 event);
2426 if (ret != LTTCOMM_OK) {
2427 goto error;
2428 }
2429
2430 kernel_wait_quiescent(kernel_tracer_fd);
2431 break;
2432 }
2433 case LTTNG_DOMAIN_UST:
2434 {
2435 struct ltt_ust_channel *uchan;
2436 struct ltt_ust_event *uevent;
2437 struct lttng_channel *attr;
2438
2439 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2440 channel_name);
2441 if (uchan == NULL) {
2442 /* Create default channel */
2443 attr = channel_new_default_attr(domain);
2444 if (attr == NULL) {
2445 ret = LTTCOMM_FATAL;
2446 goto error;
2447 }
2448 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2449
2450 /* Use the internal command enable channel */
2451 ret = cmd_enable_channel(session, domain, attr);
2452 if (ret < 0) {
2453 goto error;
2454 }
2455
2456 free(attr);
2457
2458 /* Get the newly created channel reference back */
2459 uchan = trace_ust_find_channel_by_name(
2460 usess->domain_global.channels, channel_name);
2461 if (uchan == NULL) {
2462 /* Something is really wrong */
2463 ret = LTTCOMM_FATAL;
2464 goto error;
2465 }
2466 }
2467
2468 uevent = trace_ust_find_event_by_name(uchan->events, event->name);
2469 if (uevent == NULL) {
2470 uevent = trace_ust_create_event(event);
2471 if (uevent == NULL) {
2472 ret = LTTCOMM_FATAL;
2473 goto error;
2474 }
2475
2476 }
2477
2478 ret = ust_app_create_event_all(usess, uchan, uevent);
2479 if (ret < 0) {
2480 ret = LTTCOMM_UST_ENABLE_FAIL;
2481 goto error;
2482 }
2483
2484 /* Add ltt ust event to channel */
2485 rcu_read_lock();
2486 hashtable_add_unique(uchan->events, &uevent->node);
2487 rcu_read_unlock();
2488
2489 uevent->enabled = 1;
2490
2491 DBG3("UST ltt event %s added to channel %s", uevent->attr.name,
2492 uchan->name);
2493 break;
2494 }
2495 case LTTNG_DOMAIN_UST_EXEC_NAME:
2496 case LTTNG_DOMAIN_UST_PID:
2497 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2498 default:
2499 ret = LTTCOMM_NOT_IMPLEMENTED;
2500 goto error;
2501 }
2502
2503 ret = LTTCOMM_OK;
2504
2505 error:
2506 return ret;
2507 }
2508
2509 /*
2510 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2511 */
2512 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2513 char *channel_name, int event_type)
2514 {
2515 int ret;
2516 struct ltt_kernel_channel *kchan;
2517
2518 switch (domain) {
2519 case LTTNG_DOMAIN_KERNEL:
2520 kchan = trace_kernel_get_channel_by_name(channel_name,
2521 session->kernel_session);
2522 if (kchan == NULL) {
2523 /* This call will notify the kernel thread */
2524 ret = channel_kernel_create(session->kernel_session, NULL,
2525 kernel_poll_pipe[1]);
2526 if (ret != LTTCOMM_OK) {
2527 goto error;
2528 }
2529 }
2530
2531 /* Get the newly created kernel channel pointer */
2532 kchan = trace_kernel_get_channel_by_name(channel_name,
2533 session->kernel_session);
2534 if (kchan == NULL) {
2535 /* This sould not happen... */
2536 ret = LTTCOMM_FATAL;
2537 goto error;
2538 }
2539
2540 switch (event_type) {
2541 case LTTNG_KERNEL_SYSCALL:
2542 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2543 kchan, kernel_tracer_fd);
2544 break;
2545 case LTTNG_KERNEL_TRACEPOINT:
2546 /*
2547 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2548 * events already registered to the channel.
2549 */
2550 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2551 kchan, kernel_tracer_fd);
2552 break;
2553 case LTTNG_KERNEL_ALL:
2554 /* Enable syscalls and tracepoints */
2555 ret = event_kernel_enable_all(session->kernel_session,
2556 kchan, kernel_tracer_fd);
2557 break;
2558 default:
2559 ret = LTTCOMM_KERN_ENABLE_FAIL;
2560 goto error;
2561 }
2562 if (ret != LTTCOMM_OK) {
2563 goto error;
2564 }
2565
2566 kernel_wait_quiescent(kernel_tracer_fd);
2567 break;
2568 default:
2569 /* TODO: Userspace tracing */
2570 ret = LTTCOMM_NOT_IMPLEMENTED;
2571 goto error;
2572 }
2573
2574 ret = LTTCOMM_OK;
2575
2576 error:
2577 return ret;
2578 }
2579
2580 /*
2581 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2582 */
2583 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2584 {
2585 int ret;
2586 ssize_t nb_events = 0;
2587
2588 switch (domain) {
2589 case LTTNG_DOMAIN_KERNEL:
2590 nb_events = kernel_list_events(kernel_tracer_fd, events);
2591 if (nb_events < 0) {
2592 ret = LTTCOMM_KERN_LIST_FAIL;
2593 goto error;
2594 }
2595 break;
2596 case LTTNG_DOMAIN_UST:
2597 nb_events = ust_app_list_events(events);
2598 if (nb_events < 0) {
2599 ret = LTTCOMM_UST_LIST_FAIL;
2600 goto error;
2601 }
2602 break;
2603 default:
2604 ret = LTTCOMM_NOT_IMPLEMENTED;
2605 goto error;
2606 }
2607
2608 return nb_events;
2609
2610 error:
2611 /* Return negative value to differentiate return code */
2612 return -ret;
2613 }
2614
2615 /*
2616 * Command LTTNG_START_TRACE processed by the client thread.
2617 */
2618 static int cmd_start_trace(struct ltt_session *session)
2619 {
2620 int ret;
2621 struct ltt_kernel_session *ksession;
2622 struct ltt_ust_session *usess;
2623
2624 /* Short cut */
2625 ksession = session->kernel_session;
2626 usess = session->ust_session;
2627
2628 if (session->enabled)
2629 return LTTCOMM_UST_START_FAIL;
2630 session->enabled = 1;
2631
2632 /* Kernel tracing */
2633 if (ksession != NULL) {
2634 struct ltt_kernel_channel *kchan;
2635
2636 /* Open kernel metadata */
2637 if (ksession->metadata == NULL) {
2638 ret = kernel_open_metadata(ksession, ksession->trace_path);
2639 if (ret < 0) {
2640 ret = LTTCOMM_KERN_META_FAIL;
2641 goto error;
2642 }
2643 }
2644
2645 /* Open kernel metadata stream */
2646 if (ksession->metadata_stream_fd == 0) {
2647 ret = kernel_open_metadata_stream(ksession);
2648 if (ret < 0) {
2649 ERR("Kernel create metadata stream failed");
2650 ret = LTTCOMM_KERN_STREAM_FAIL;
2651 goto error;
2652 }
2653 }
2654
2655 /* For each channel */
2656 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2657 if (kchan->stream_count == 0) {
2658 ret = kernel_open_channel_stream(kchan);
2659 if (ret < 0) {
2660 ret = LTTCOMM_KERN_STREAM_FAIL;
2661 goto error;
2662 }
2663 /* Update the stream global counter */
2664 ksession->stream_count_global += ret;
2665 }
2666 }
2667
2668 /* Setup kernel consumer socket and send fds to it */
2669 ret = init_kernel_tracing(ksession);
2670 if (ret < 0) {
2671 ret = LTTCOMM_KERN_START_FAIL;
2672 goto error;
2673 }
2674
2675 /* This start the kernel tracing */
2676 ret = kernel_start_session(ksession);
2677 if (ret < 0) {
2678 ret = LTTCOMM_KERN_START_FAIL;
2679 goto error;
2680 }
2681
2682 /* Quiescent wait after starting trace */
2683 kernel_wait_quiescent(kernel_tracer_fd);
2684 }
2685
2686 /* Flag session that trace should start automatically */
2687 if (usess) {
2688 usess->start_trace = 1;
2689
2690 ret = ust_app_start_trace_all(usess);
2691 if (ret < 0) {
2692 ret = LTTCOMM_UST_START_FAIL;
2693 goto error;
2694 }
2695 }
2696
2697 ret = LTTCOMM_OK;
2698
2699 error:
2700 return ret;
2701 }
2702
2703 /*
2704 * Command LTTNG_STOP_TRACE processed by the client thread.
2705 */
2706 static int cmd_stop_trace(struct ltt_session *session)
2707 {
2708 int ret;
2709 struct ltt_kernel_channel *kchan;
2710 struct ltt_kernel_session *ksession;
2711 struct ltt_ust_session *usess;
2712
2713 /* Short cut */
2714 ksession = session->kernel_session;
2715 usess = session->ust_session;
2716
2717 if (!session->enabled)
2718 return LTTCOMM_UST_START_FAIL;
2719 session->enabled = 0;
2720
2721 /* Kernel tracer */
2722 if (ksession != NULL) {
2723 DBG("Stop kernel tracing");
2724
2725 /* Flush all buffers before stopping */
2726 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2727 if (ret < 0) {
2728 ERR("Kernel metadata flush failed");
2729 }
2730
2731 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2732 ret = kernel_flush_buffer(kchan);
2733 if (ret < 0) {
2734 ERR("Kernel flush buffer error");
2735 }
2736 }
2737
2738 ret = kernel_stop_session(ksession);
2739 if (ret < 0) {
2740 ret = LTTCOMM_KERN_STOP_FAIL;
2741 goto error;
2742 }
2743
2744 kernel_wait_quiescent(kernel_tracer_fd);
2745 }
2746
2747 if (usess) {
2748 usess->start_trace = 0;
2749
2750 ret = ust_app_stop_trace_all(usess);
2751 if (ret < 0) {
2752 ret = LTTCOMM_UST_START_FAIL;
2753 goto error;
2754 }
2755 }
2756
2757 ret = LTTCOMM_OK;
2758
2759 error:
2760 return ret;
2761 }
2762
2763 /*
2764 * Command LTTNG_CREATE_SESSION processed by the client thread.
2765 */
2766 static int cmd_create_session(char *name, char *path)
2767 {
2768 int ret;
2769
2770 ret = session_create(name, path);
2771 if (ret != LTTCOMM_OK) {
2772 goto error;
2773 }
2774
2775 ret = LTTCOMM_OK;
2776
2777 error:
2778 return ret;
2779 }
2780
2781 /*
2782 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2783 */
2784 static int cmd_destroy_session(struct ltt_session *session, char *name)
2785 {
2786 int ret;
2787
2788 /* Clean kernel session teardown */
2789 teardown_kernel_session(session);
2790 /* UST session teardown */
2791 teardown_ust_session(session);
2792
2793 /*
2794 * Must notify the kernel thread here to update it's poll setin order
2795 * to remove the channel(s)' fd just destroyed.
2796 */
2797 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2798 if (ret < 0) {
2799 perror("write kernel poll pipe");
2800 }
2801
2802 ret = session_destroy(session);
2803
2804 return ret;
2805 }
2806
2807 /*
2808 * Command LTTNG_CALIBRATE processed by the client thread.
2809 */
2810 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2811 {
2812 int ret;
2813
2814 switch (domain) {
2815 case LTTNG_DOMAIN_KERNEL:
2816 {
2817 struct lttng_kernel_calibrate kcalibrate;
2818
2819 kcalibrate.type = calibrate->type;
2820 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2821 if (ret < 0) {
2822 ret = LTTCOMM_KERN_ENABLE_FAIL;
2823 goto error;
2824 }
2825 break;
2826 }
2827 default:
2828 /* TODO: Userspace tracing */
2829 ret = LTTCOMM_NOT_IMPLEMENTED;
2830 goto error;
2831 }
2832
2833 ret = LTTCOMM_OK;
2834
2835 error:
2836 return ret;
2837 }
2838
2839 /*
2840 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2841 */
2842 static int cmd_register_consumer(struct ltt_session *session, int domain,
2843 char *sock_path)
2844 {
2845 int ret, sock;
2846
2847 switch (domain) {
2848 case LTTNG_DOMAIN_KERNEL:
2849 /* Can't register a consumer if there is already one */
2850 if (session->kernel_session->consumer_fd != 0) {
2851 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2852 goto error;
2853 }
2854
2855 sock = lttcomm_connect_unix_sock(sock_path);
2856 if (sock < 0) {
2857 ret = LTTCOMM_CONNECT_FAIL;
2858 goto error;
2859 }
2860
2861 session->kernel_session->consumer_fd = sock;
2862 break;
2863 default:
2864 /* TODO: Userspace tracing */
2865 ret = LTTCOMM_NOT_IMPLEMENTED;
2866 goto error;
2867 }
2868
2869 ret = LTTCOMM_OK;
2870
2871 error:
2872 return ret;
2873 }
2874
2875 /*
2876 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2877 */
2878 static ssize_t cmd_list_domains(struct ltt_session *session,
2879 struct lttng_domain **domains)
2880 {
2881 int ret, index = 0;
2882 ssize_t nb_dom = 0;
2883
2884 if (session->kernel_session != NULL) {
2885 DBG3("Listing domains found kernel domain");
2886 nb_dom++;
2887 }
2888
2889 if (session->ust_session != NULL) {
2890 DBG3("Listing domains found UST global domain");
2891 nb_dom++;
2892 }
2893
2894 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2895 if (*domains == NULL) {
2896 ret = -LTTCOMM_FATAL;
2897 goto error;
2898 }
2899
2900 if (session->kernel_session != NULL) {
2901 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2902 index++;
2903 }
2904
2905 if (session->ust_session != NULL) {
2906 (*domains)[index].type = LTTNG_DOMAIN_UST;
2907 index++;
2908 }
2909
2910 return nb_dom;
2911
2912 error:
2913 return ret;
2914 }
2915
2916 /*
2917 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2918 */
2919 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
2920 struct lttng_channel **channels)
2921 {
2922 int ret;
2923 ssize_t nb_chan = 0;
2924
2925 switch (domain) {
2926 case LTTNG_DOMAIN_KERNEL:
2927 if (session->kernel_session != NULL) {
2928 nb_chan = session->kernel_session->channel_count;
2929 }
2930 DBG3("Number of kernel channels %zd", nb_chan);
2931 break;
2932 case LTTNG_DOMAIN_UST:
2933 if (session->ust_session != NULL) {
2934 nb_chan = hashtable_get_count(
2935 session->ust_session->domain_global.channels);
2936 }
2937 DBG3("Number of UST global channels %zd", nb_chan);
2938 break;
2939 default:
2940 *channels = NULL;
2941 ret = -LTTCOMM_NOT_IMPLEMENTED;
2942 goto error;
2943 }
2944
2945 if (nb_chan > 0) {
2946 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
2947 if (*channels == NULL) {
2948 ret = -LTTCOMM_FATAL;
2949 goto error;
2950 }
2951
2952 list_lttng_channels(domain, session, *channels);
2953 } else {
2954 *channels = NULL;
2955 }
2956
2957 return nb_chan;
2958
2959 error:
2960 return ret;
2961 }
2962
2963 /*
2964 * Command LTTNG_LIST_EVENTS processed by the client thread.
2965 */
2966 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
2967 char *channel_name, struct lttng_event **events)
2968 {
2969 int ret = 0;
2970 ssize_t nb_event = 0;
2971
2972 switch (domain) {
2973 case LTTNG_DOMAIN_KERNEL:
2974 if (session->kernel_session != NULL) {
2975 nb_event = list_lttng_kernel_events(channel_name,
2976 session->kernel_session, events);
2977 }
2978 break;
2979 case LTTNG_DOMAIN_UST:
2980 {
2981 if (session->ust_session != NULL) {
2982 nb_event = list_lttng_ust_global_events(channel_name,
2983 &session->ust_session->domain_global, events);
2984 }
2985 break;
2986 }
2987 default:
2988 ret = -LTTCOMM_NOT_IMPLEMENTED;
2989 goto error;
2990 }
2991
2992 ret = nb_event;
2993
2994 error:
2995 return ret;
2996 }
2997
2998 /*
2999 * Process the command requested by the lttng client within the command
3000 * context structure. This function make sure that the return structure (llm)
3001 * is set and ready for transmission before returning.
3002 *
3003 * Return any error encountered or 0 for success.
3004 */
3005 static int process_client_msg(struct command_ctx *cmd_ctx)
3006 {
3007 int ret = LTTCOMM_OK;
3008 int need_tracing_session = 1;
3009
3010 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3011
3012 /*
3013 * Check for command that don't needs to allocate a returned payload. We do
3014 * this here so we don't have to make the call for no payload at each
3015 * command.
3016 */
3017 switch(cmd_ctx->lsm->cmd_type) {
3018 case LTTNG_LIST_SESSIONS:
3019 case LTTNG_LIST_TRACEPOINTS:
3020 case LTTNG_LIST_DOMAINS:
3021 case LTTNG_LIST_CHANNELS:
3022 case LTTNG_LIST_EVENTS:
3023 break;
3024 default:
3025 /* Setup lttng message with no payload */
3026 ret = setup_lttng_msg(cmd_ctx, 0);
3027 if (ret < 0) {
3028 /* This label does not try to unlock the session */
3029 goto init_setup_error;
3030 }
3031 }
3032
3033 /* Commands that DO NOT need a session. */
3034 switch (cmd_ctx->lsm->cmd_type) {
3035 case LTTNG_CALIBRATE:
3036 case LTTNG_CREATE_SESSION:
3037 case LTTNG_LIST_SESSIONS:
3038 case LTTNG_LIST_TRACEPOINTS:
3039 need_tracing_session = 0;
3040 break;
3041 default:
3042 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3043 session_lock_list();
3044 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3045 session_unlock_list();
3046 if (cmd_ctx->session == NULL) {
3047 if (cmd_ctx->lsm->session.name != NULL) {
3048 ret = LTTCOMM_SESS_NOT_FOUND;
3049 } else {
3050 /* If no session name specified */
3051 ret = LTTCOMM_SELECT_SESS;
3052 }
3053 goto error;
3054 } else {
3055 /* Acquire lock for the session */
3056 session_lock(cmd_ctx->session);
3057 }
3058 break;
3059 }
3060
3061 /*
3062 * Check domain type for specific "pre-action".
3063 */
3064 switch (cmd_ctx->lsm->domain.type) {
3065 case LTTNG_DOMAIN_KERNEL:
3066 /* Kernel tracer check */
3067 if (kernel_tracer_fd == 0) {
3068 /* Basically, load kernel tracer modules */
3069 init_kernel_tracer();
3070 if (kernel_tracer_fd == 0) {
3071 ret = LTTCOMM_KERN_NA;
3072 goto error;
3073 }
3074 }
3075
3076 /* Need a session for kernel command */
3077 if (need_tracing_session) {
3078 if (cmd_ctx->session->kernel_session == NULL) {
3079 ret = create_kernel_session(cmd_ctx->session);
3080 if (ret < 0) {
3081 ret = LTTCOMM_KERN_SESS_FAIL;
3082 goto error;
3083 }
3084 }
3085
3086 /* Start the kernel consumer daemon */
3087 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3088 if (kconsumer_data.pid == 0 &&
3089 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3090 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3091 ret = start_consumerd(&kconsumer_data);
3092 if (ret < 0) {
3093 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3094 goto error;
3095 }
3096 } else {
3097 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3098 }
3099 }
3100 break;
3101 case LTTNG_DOMAIN_UST:
3102 {
3103 if (need_tracing_session) {
3104 if (cmd_ctx->session->ust_session == NULL) {
3105 ret = create_ust_session(cmd_ctx->session,
3106 &cmd_ctx->lsm->domain);
3107 if (ret != LTTCOMM_OK) {
3108 goto error;
3109 }
3110 }
3111 /* Start the UST consumer daemons */
3112 /* 64-bit */
3113 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3114 if (consumerd64_bindir[0] != '\0' &&
3115 ustconsumer64_data.pid == 0 &&
3116 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3117 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3118 ret = start_consumerd(&ustconsumer64_data);
3119 if (ret < 0) {
3120 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3121 ust_consumerd64_fd = -EINVAL;
3122 goto error;
3123 }
3124
3125 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3126 } else {
3127 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3128 }
3129 /* 32-bit */
3130 if (consumerd32_bindir[0] != '\0' &&
3131 ustconsumer32_data.pid == 0 &&
3132 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3133 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3134 ret = start_consumerd(&ustconsumer32_data);
3135 if (ret < 0) {
3136 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3137 ust_consumerd32_fd = -EINVAL;
3138 goto error;
3139 }
3140 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3141 } else {
3142 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3143 }
3144 }
3145 break;
3146 }
3147 default:
3148 break;
3149 }
3150
3151 /* Process by command type */
3152 switch (cmd_ctx->lsm->cmd_type) {
3153 case LTTNG_ADD_CONTEXT:
3154 {
3155 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3156 cmd_ctx->lsm->u.context.channel_name,
3157 cmd_ctx->lsm->u.context.event_name,
3158 &cmd_ctx->lsm->u.context.ctx);
3159 break;
3160 }
3161 case LTTNG_DISABLE_CHANNEL:
3162 {
3163 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3164 cmd_ctx->lsm->u.disable.channel_name);
3165 break;
3166 }
3167 case LTTNG_DISABLE_EVENT:
3168 {
3169 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3170 cmd_ctx->lsm->u.disable.channel_name,
3171 cmd_ctx->lsm->u.disable.name);
3172 ret = LTTCOMM_OK;
3173 break;
3174 }
3175 case LTTNG_DISABLE_ALL_EVENT:
3176 {
3177 DBG("Disabling all events");
3178
3179 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3180 cmd_ctx->lsm->u.disable.channel_name);
3181 break;
3182 }
3183 case LTTNG_ENABLE_CHANNEL:
3184 {
3185 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3186 &cmd_ctx->lsm->u.channel.chan);
3187 break;
3188 }
3189 case LTTNG_ENABLE_EVENT:
3190 {
3191 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3192 cmd_ctx->lsm->u.enable.channel_name,
3193 &cmd_ctx->lsm->u.enable.event);
3194 break;
3195 }
3196 case LTTNG_ENABLE_ALL_EVENT:
3197 {
3198 DBG("Enabling all events");
3199
3200 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3201 cmd_ctx->lsm->u.enable.channel_name,
3202 cmd_ctx->lsm->u.enable.event.type);
3203 break;
3204 }
3205 case LTTNG_LIST_TRACEPOINTS:
3206 {
3207 struct lttng_event *events;
3208 ssize_t nb_events;
3209
3210 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3211 if (nb_events < 0) {
3212 ret = -nb_events;
3213 goto error;
3214 }
3215
3216 /*
3217 * Setup lttng message with payload size set to the event list size in
3218 * bytes and then copy list into the llm payload.
3219 */
3220 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3221 if (ret < 0) {
3222 free(events);
3223 goto setup_error;
3224 }
3225
3226 /* Copy event list into message payload */
3227 memcpy(cmd_ctx->llm->payload, events,
3228 sizeof(struct lttng_event) * nb_events);
3229
3230 free(events);
3231
3232 ret = LTTCOMM_OK;
3233 break;
3234 }
3235 case LTTNG_START_TRACE:
3236 {
3237 ret = cmd_start_trace(cmd_ctx->session);
3238 break;
3239 }
3240 case LTTNG_STOP_TRACE:
3241 {
3242 ret = cmd_stop_trace(cmd_ctx->session);
3243 break;
3244 }
3245 case LTTNG_CREATE_SESSION:
3246 {
3247 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3248 cmd_ctx->lsm->session.path);
3249 break;
3250 }
3251 case LTTNG_DESTROY_SESSION:
3252 {
3253 ret = cmd_destroy_session(cmd_ctx->session,
3254 cmd_ctx->lsm->session.name);
3255 break;
3256 }
3257 case LTTNG_LIST_DOMAINS:
3258 {
3259 ssize_t nb_dom;
3260 struct lttng_domain *domains;
3261
3262 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3263 if (nb_dom < 0) {
3264 ret = -nb_dom;
3265 goto error;
3266 }
3267
3268 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3269 if (ret < 0) {
3270 goto setup_error;
3271 }
3272
3273 /* Copy event list into message payload */
3274 memcpy(cmd_ctx->llm->payload, domains,
3275 nb_dom * sizeof(struct lttng_domain));
3276
3277 free(domains);
3278
3279 ret = LTTCOMM_OK;
3280 break;
3281 }
3282 case LTTNG_LIST_CHANNELS:
3283 {
3284 size_t nb_chan;
3285 struct lttng_channel *channels;
3286
3287 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
3288 cmd_ctx->session, &channels);
3289 if (nb_chan < 0) {
3290 ret = -nb_chan;
3291 goto error;
3292 }
3293
3294 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3295 if (ret < 0) {
3296 goto setup_error;
3297 }
3298
3299 /* Copy event list into message payload */
3300 memcpy(cmd_ctx->llm->payload, channels,
3301 nb_chan * sizeof(struct lttng_channel));
3302
3303 free(channels);
3304
3305 ret = LTTCOMM_OK;
3306 break;
3307 }
3308 case LTTNG_LIST_EVENTS:
3309 {
3310 ssize_t nb_event;
3311 struct lttng_event *events = NULL;
3312
3313 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
3314 cmd_ctx->lsm->u.list.channel_name, &events);
3315 if (nb_event < 0) {
3316 ret = -nb_event;
3317 goto error;
3318 }
3319
3320 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3321 if (ret < 0) {
3322 goto setup_error;
3323 }
3324
3325 /* Copy event list into message payload */
3326 memcpy(cmd_ctx->llm->payload, events,
3327 nb_event * sizeof(struct lttng_event));
3328
3329 free(events);
3330
3331 ret = LTTCOMM_OK;
3332 break;
3333 }
3334 case LTTNG_LIST_SESSIONS:
3335 {
3336 session_lock_list();
3337
3338 if (session_list_ptr->count == 0) {
3339 ret = LTTCOMM_NO_SESSION;
3340 session_unlock_list();
3341 goto error;
3342 }
3343
3344 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) *
3345 session_list_ptr->count);
3346 if (ret < 0) {
3347 session_unlock_list();
3348 goto setup_error;
3349 }
3350
3351 /* Filled the session array */
3352 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
3353
3354 session_unlock_list();
3355
3356 ret = LTTCOMM_OK;
3357 break;
3358 }
3359 case LTTNG_CALIBRATE:
3360 {
3361 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3362 &cmd_ctx->lsm->u.calibrate);
3363 break;
3364 }
3365 case LTTNG_REGISTER_CONSUMER:
3366 {
3367 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3368 cmd_ctx->lsm->u.reg.path);
3369 break;
3370 }
3371 default:
3372 ret = LTTCOMM_UND;
3373 break;
3374 }
3375
3376 error:
3377 if (cmd_ctx->llm == NULL) {
3378 DBG("Missing llm structure. Allocating one.");
3379 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3380 goto setup_error;
3381 }
3382 }
3383 /* Set return code */
3384 cmd_ctx->llm->ret_code = ret;
3385 setup_error:
3386 if (cmd_ctx->session) {
3387 session_unlock(cmd_ctx->session);
3388 }
3389 init_setup_error:
3390 return ret;
3391 }
3392
3393 /*
3394 * This thread manage all clients request using the unix client socket for
3395 * communication.
3396 */
3397 static void *thread_manage_clients(void *data)
3398 {
3399 int sock = 0, ret, i, pollfd;
3400 uint32_t revents, nb_fd;
3401 struct command_ctx *cmd_ctx = NULL;
3402 struct lttng_poll_event events;
3403
3404 DBG("[thread] Manage client started");
3405
3406 rcu_register_thread();
3407
3408 ret = lttcomm_listen_unix_sock(client_sock);
3409 if (ret < 0) {
3410 goto error;
3411 }
3412
3413 /*
3414 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3415 * more will be added to this poll set.
3416 */
3417 ret = create_thread_poll_set(&events, 2);
3418 if (ret < 0) {
3419 goto error;
3420 }
3421
3422 /* Add the application registration socket */
3423 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3424 if (ret < 0) {
3425 goto error;
3426 }
3427
3428 /*
3429 * Notify parent pid that we are ready to accept command for client side.
3430 */
3431 if (opt_sig_parent) {
3432 kill(ppid, SIGCHLD);
3433 }
3434
3435 while (1) {
3436 DBG("Accepting client command ...");
3437
3438 nb_fd = LTTNG_POLL_GETNB(&events);
3439
3440 /* Inifinite blocking call, waiting for transmission */
3441 ret = lttng_poll_wait(&events, -1);
3442 if (ret < 0) {
3443 goto error;
3444 }
3445
3446 for (i = 0; i < nb_fd; i++) {
3447 /* Fetch once the poll data */
3448 revents = LTTNG_POLL_GETEV(&events, i);
3449 pollfd = LTTNG_POLL_GETFD(&events, i);
3450
3451 /* Thread quit pipe has been closed. Killing thread. */
3452 ret = check_thread_quit_pipe(pollfd, revents);
3453 if (ret) {
3454 goto error;
3455 }
3456
3457 /* Event on the registration socket */
3458 if (pollfd == client_sock) {
3459 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3460 ERR("Client socket poll error");
3461 goto error;
3462 }
3463 }
3464 }
3465
3466 DBG("Wait for client response");
3467
3468 sock = lttcomm_accept_unix_sock(client_sock);
3469 if (sock < 0) {
3470 goto error;
3471 }
3472
3473 /* Allocate context command to process the client request */
3474 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3475 if (cmd_ctx == NULL) {
3476 perror("zmalloc cmd_ctx");
3477 goto error;
3478 }
3479
3480 /* Allocate data buffer for reception */
3481 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3482 if (cmd_ctx->lsm == NULL) {
3483 perror("zmalloc cmd_ctx->lsm");
3484 goto error;
3485 }
3486
3487 cmd_ctx->llm = NULL;
3488 cmd_ctx->session = NULL;
3489
3490 /*
3491 * Data is received from the lttng client. The struct
3492 * lttcomm_session_msg (lsm) contains the command and data request of
3493 * the client.
3494 */
3495 DBG("Receiving data from client ...");
3496 ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm,
3497 sizeof(struct lttcomm_session_msg));
3498 if (ret <= 0) {
3499 DBG("Nothing recv() from client... continuing");
3500 close(sock);
3501 free(cmd_ctx);
3502 continue;
3503 }
3504
3505 // TODO: Validate cmd_ctx including sanity check for
3506 // security purpose.
3507
3508 rcu_thread_online();
3509 /*
3510 * This function dispatch the work to the kernel or userspace tracer
3511 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3512 * informations for the client. The command context struct contains
3513 * everything this function may needs.
3514 */
3515 ret = process_client_msg(cmd_ctx);
3516 rcu_thread_offline();
3517 if (ret < 0) {
3518 /*
3519 * TODO: Inform client somehow of the fatal error. At
3520 * this point, ret < 0 means that a zmalloc failed
3521 * (ENOMEM). Error detected but still accept command.
3522 */
3523 clean_command_ctx(&cmd_ctx);
3524 continue;
3525 }
3526
3527 DBG("Sending response (size: %d, retcode: %s)",
3528 cmd_ctx->lttng_msg_size,
3529 lttng_strerror(-cmd_ctx->llm->ret_code));
3530 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3531 if (ret < 0) {
3532 ERR("Failed to send data back to client");
3533 }
3534
3535 clean_command_ctx(&cmd_ctx);
3536
3537 /* End of transmission */
3538 close(sock);
3539 }
3540
3541 error:
3542 DBG("Client thread dying");
3543 unlink(client_unix_sock_path);
3544 close(client_sock);
3545 close(sock);
3546
3547 lttng_poll_clean(&events);
3548 clean_command_ctx(&cmd_ctx);
3549
3550 rcu_unregister_thread();
3551 return NULL;
3552 }
3553
3554
3555 /*
3556 * usage function on stderr
3557 */
3558 static void usage(void)
3559 {
3560 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3561 fprintf(stderr, " -h, --help Display this usage.\n");
3562 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3563 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3564 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3565 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3566 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
3567 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
3568 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
3569 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
3570 fprintf(stderr, " --ustconsumerd32 PATH Specify path for the 32-bit UST consumer daemon binary\n");
3571 fprintf(stderr, " --ustconsumerd64 PATH Specify path for the 64-bit UST consumer daemon binary\n");
3572 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3573 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3574 fprintf(stderr, " -V, --version Show version number.\n");
3575 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3576 fprintf(stderr, " -q, --quiet No output at all.\n");
3577 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3578 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3579 }
3580
3581 /*
3582 * daemon argument parsing
3583 */
3584 static int parse_args(int argc, char **argv)
3585 {
3586 int c;
3587
3588 static struct option long_options[] = {
3589 { "client-sock", 1, 0, 'c' },
3590 { "apps-sock", 1, 0, 'a' },
3591 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3592 { "kconsumerd-err-sock", 1, 0, 'E' },
3593 { "ustconsumerd64", 1, 0, 't' },
3594 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
3595 { "ustconsumerd64-err-sock", 1, 0, 'F' },
3596 { "ustconsumerd32", 1, 0, 'u' },
3597 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
3598 { "ustconsumerd32-err-sock", 1, 0, 'H' },
3599 { "daemonize", 0, 0, 'd' },
3600 { "sig-parent", 0, 0, 'S' },
3601 { "help", 0, 0, 'h' },
3602 { "group", 1, 0, 'g' },
3603 { "version", 0, 0, 'V' },
3604 { "quiet", 0, 0, 'q' },
3605 { "verbose", 0, 0, 'v' },
3606 { "verbose-consumer", 0, 0, 'Z' },
3607 { NULL, 0, 0, 0 }
3608 };
3609
3610 while (1) {
3611 int option_index = 0;
3612 c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:C:E:D:F:Z:u:t",
3613 long_options, &option_index);
3614 if (c == -1) {
3615 break;
3616 }
3617
3618 switch (c) {
3619 case 0:
3620 fprintf(stderr, "option %s", long_options[option_index].name);
3621 if (optarg) {
3622 fprintf(stderr, " with arg %s\n", optarg);
3623 }
3624 break;
3625 case 'c':
3626 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3627 break;
3628 case 'a':
3629 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3630 break;
3631 case 'd':
3632 opt_daemon = 1;
3633 break;
3634 case 'g':
3635 opt_tracing_group = optarg;
3636 break;
3637 case 'h':
3638 usage();
3639 exit(EXIT_FAILURE);
3640 case 'V':
3641 fprintf(stdout, "%s\n", VERSION);
3642 exit(EXIT_SUCCESS);
3643 case 'S':
3644 opt_sig_parent = 1;
3645 break;
3646 case 'E':
3647 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3648 break;
3649 case 'C':
3650 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3651 break;
3652 case 'F':
3653 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3654 break;
3655 case 'D':
3656 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3657 break;
3658 case 'H':
3659 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3660 break;
3661 case 'G':
3662 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3663 break;
3664 case 'q':
3665 opt_quiet = 1;
3666 break;
3667 case 'v':
3668 /* Verbose level can increase using multiple -v */
3669 opt_verbose += 1;
3670 break;
3671 case 'Z':
3672 opt_verbose_consumer += 1;
3673 break;
3674 case 'u':
3675 consumerd32_bindir = optarg;
3676 break;
3677 case 't':
3678 consumerd64_bindir = optarg;
3679 break;
3680 default:
3681 /* Unknown option or other error.
3682 * Error is printed by getopt, just return */
3683 return -1;
3684 }
3685 }
3686
3687 return 0;
3688 }
3689
3690 /*
3691 * Creates the two needed socket by the daemon.
3692 * apps_sock - The communication socket for all UST apps.
3693 * client_sock - The communication of the cli tool (lttng).
3694 */
3695 static int init_daemon_socket(void)
3696 {
3697 int ret = 0;
3698 mode_t old_umask;
3699
3700 old_umask = umask(0);
3701
3702 /* Create client tool unix socket */
3703 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3704 if (client_sock < 0) {
3705 ERR("Create unix sock failed: %s", client_unix_sock_path);
3706 ret = -1;
3707 goto end;
3708 }
3709
3710 /* File permission MUST be 660 */
3711 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3712 if (ret < 0) {
3713 ERR("Set file permissions failed: %s", client_unix_sock_path);
3714 perror("chmod");
3715 goto end;
3716 }
3717
3718 /* Create the application unix socket */
3719 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3720 if (apps_sock < 0) {
3721 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3722 ret = -1;
3723 goto end;
3724 }
3725
3726 /* File permission MUST be 666 */
3727 ret = chmod(apps_unix_sock_path,
3728 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3729 if (ret < 0) {
3730 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3731 perror("chmod");
3732 goto end;
3733 }
3734
3735 end:
3736 umask(old_umask);
3737 return ret;
3738 }
3739
3740 /*
3741 * Check if the global socket is available, and if a daemon is answering at the
3742 * other side. If yes, error is returned.
3743 */
3744 static int check_existing_daemon(void)
3745 {
3746 if (access(client_unix_sock_path, F_OK) < 0 &&
3747 access(apps_unix_sock_path, F_OK) < 0) {
3748 return 0;
3749 }
3750
3751 /* Is there anybody out there ? */
3752 if (lttng_session_daemon_alive()) {
3753 return -EEXIST;
3754 } else {
3755 return 0;
3756 }
3757 }
3758
3759 /*
3760 * Set the tracing group gid onto the client socket.
3761 *
3762 * Race window between mkdir and chown is OK because we are going from more
3763 * permissive (root.root) to les permissive (root.tracing).
3764 */
3765 static int set_permissions(void)
3766 {
3767 int ret;
3768 gid_t gid;
3769
3770 gid = allowed_group();
3771 if (gid < 0) {
3772 if (is_root) {
3773 WARN("No tracing group detected");
3774 ret = 0;
3775 } else {
3776 ERR("Missing tracing group. Aborting execution.");
3777 ret = -1;
3778 }
3779 goto end;
3780 }
3781
3782 /* Set lttng run dir */
3783 ret = chown(LTTNG_RUNDIR, 0, gid);
3784 if (ret < 0) {
3785 ERR("Unable to set group on " LTTNG_RUNDIR);
3786 perror("chown");
3787 }
3788
3789 /* lttng client socket path */
3790 ret = chown(client_unix_sock_path, 0, gid);
3791 if (ret < 0) {
3792 ERR("Unable to set group on %s", client_unix_sock_path);
3793 perror("chown");
3794 }
3795
3796 /* kconsumer error socket path */
3797 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
3798 if (ret < 0) {
3799 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
3800 perror("chown");
3801 }
3802
3803 /* 64-bit ustconsumer error socket path */
3804 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
3805 if (ret < 0) {
3806 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
3807 perror("chown");
3808 }
3809
3810 /* 32-bit ustconsumer compat32 error socket path */
3811 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
3812 if (ret < 0) {
3813 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
3814 perror("chown");
3815 }
3816
3817 DBG("All permissions are set");
3818
3819 end:
3820 return ret;
3821 }
3822
3823 /*
3824 * Create the pipe used to wake up the kernel thread.
3825 */
3826 static int create_kernel_poll_pipe(void)
3827 {
3828 return pipe2(kernel_poll_pipe, O_CLOEXEC);
3829 }
3830
3831 /*
3832 * Create the application command pipe to wake thread_manage_apps.
3833 */
3834 static int create_apps_cmd_pipe(void)
3835 {
3836 return pipe2(apps_cmd_pipe, O_CLOEXEC);
3837 }
3838
3839 /*
3840 * Create the lttng run directory needed for all global sockets and pipe.
3841 */
3842 static int create_lttng_rundir(void)
3843 {
3844 int ret;
3845
3846 ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG );
3847 if (ret < 0) {
3848 if (errno != EEXIST) {
3849 ERR("Unable to create " LTTNG_RUNDIR);
3850 goto error;
3851 } else {
3852 ret = 0;
3853 }
3854 }
3855
3856 error:
3857 return ret;
3858 }
3859
3860 /*
3861 * Setup sockets and directory needed by the kconsumerd communication with the
3862 * session daemon.
3863 */
3864 static int set_consumer_sockets(struct consumer_data *consumer_data)
3865 {
3866 int ret;
3867 const char *path;
3868
3869 switch (consumer_data->type) {
3870 case LTTNG_CONSUMER_KERNEL:
3871 path = KCONSUMERD_PATH;
3872 break;
3873 case LTTNG_CONSUMER64_UST:
3874 path = USTCONSUMERD64_PATH;
3875 break;
3876 case LTTNG_CONSUMER32_UST:
3877 path = USTCONSUMERD32_PATH;
3878 break;
3879 default:
3880 ERR("Consumer type unknown");
3881 ret = -EINVAL;
3882 goto error;
3883 }
3884
3885 ret = mkdir(path, S_IRWXU | S_IRWXG);
3886 if (ret < 0) {
3887 if (errno != EEXIST) {
3888 ERR("Failed to create %s", path);
3889 goto error;
3890 }
3891 ret = 0;
3892 }
3893
3894 /* Create the kconsumerd error unix socket */
3895 consumer_data->err_sock =
3896 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
3897 if (consumer_data->err_sock < 0) {
3898 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
3899 ret = -1;
3900 goto error;
3901 }
3902
3903 /* File permission MUST be 660 */
3904 ret = chmod(consumer_data->err_unix_sock_path,
3905 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3906 if (ret < 0) {
3907 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
3908 perror("chmod");
3909 goto error;
3910 }
3911
3912 error:
3913 return ret;
3914 }
3915
3916 /*
3917 * Signal handler for the daemon
3918 *
3919 * Simply stop all worker threads, leaving main() return gracefully after
3920 * joining all threads and calling cleanup().
3921 */
3922 static void sighandler(int sig)
3923 {
3924 switch (sig) {
3925 case SIGPIPE:
3926 DBG("SIGPIPE catched");
3927 return;
3928 case SIGINT:
3929 DBG("SIGINT catched");
3930 stop_threads();
3931 break;
3932 case SIGTERM:
3933 DBG("SIGTERM catched");
3934 stop_threads();
3935 break;
3936 default:
3937 break;
3938 }
3939 }
3940
3941 /*
3942 * Setup signal handler for :
3943 * SIGINT, SIGTERM, SIGPIPE
3944 */
3945 static int set_signal_handler(void)
3946 {
3947 int ret = 0;
3948 struct sigaction sa;
3949 sigset_t sigset;
3950
3951 if ((ret = sigemptyset(&sigset)) < 0) {
3952 perror("sigemptyset");
3953 return ret;
3954 }
3955
3956 sa.sa_handler = sighandler;
3957 sa.sa_mask = sigset;
3958 sa.sa_flags = 0;
3959 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
3960 perror("sigaction");
3961 return ret;
3962 }
3963
3964 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
3965 perror("sigaction");
3966 return ret;
3967 }
3968
3969 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
3970 perror("sigaction");
3971 return ret;
3972 }
3973
3974 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3975
3976 return ret;
3977 }
3978
3979 /*
3980 * Set open files limit to unlimited. This daemon can open a large number of
3981 * file descriptors in order to consumer multiple kernel traces.
3982 */
3983 static void set_ulimit(void)
3984 {
3985 int ret;
3986 struct rlimit lim;
3987
3988 /* The kernel does not allowed an infinite limit for open files */
3989 lim.rlim_cur = 65535;
3990 lim.rlim_max = 65535;
3991
3992 ret = setrlimit(RLIMIT_NOFILE, &lim);
3993 if (ret < 0) {
3994 perror("failed to set open files limit");
3995 }
3996 }
3997
3998 /*
3999 * main
4000 */
4001 int main(int argc, char **argv)
4002 {
4003 int ret = 0;
4004 void *status;
4005 const char *home_path;
4006
4007 rcu_register_thread();
4008
4009 /* Create thread quit pipe */
4010 if ((ret = init_thread_quit_pipe()) < 0) {
4011 goto error;
4012 }
4013
4014 setup_consumerd_path();
4015
4016 /* Parse arguments */
4017 progname = argv[0];
4018 if ((ret = parse_args(argc, argv) < 0)) {
4019 goto error;
4020 }
4021
4022 /* Daemonize */
4023 if (opt_daemon) {
4024 ret = daemon(0, 0);
4025 if (ret < 0) {
4026 perror("daemon");
4027 goto error;
4028 }
4029 }
4030
4031 /* Check if daemon is UID = 0 */
4032 is_root = !getuid();
4033
4034 if (is_root) {
4035 ret = create_lttng_rundir();
4036 if (ret < 0) {
4037 goto error;
4038 }
4039
4040 if (strlen(apps_unix_sock_path) == 0) {
4041 snprintf(apps_unix_sock_path, PATH_MAX,
4042 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
4043 }
4044
4045 if (strlen(client_unix_sock_path) == 0) {
4046 snprintf(client_unix_sock_path, PATH_MAX,
4047 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
4048 }
4049
4050 /* Set global SHM for ust */
4051 if (strlen(wait_shm_path) == 0) {
4052 snprintf(wait_shm_path, PATH_MAX,
4053 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
4054 }
4055 } else {
4056 home_path = get_home_dir();
4057 if (home_path == NULL) {
4058 /* TODO: Add --socket PATH option */
4059 ERR("Can't get HOME directory for sockets creation.");
4060 ret = -EPERM;
4061 goto error;
4062 }
4063
4064 if (strlen(apps_unix_sock_path) == 0) {
4065 snprintf(apps_unix_sock_path, PATH_MAX,
4066 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
4067 }
4068
4069 /* Set the cli tool unix socket path */
4070 if (strlen(client_unix_sock_path) == 0) {
4071 snprintf(client_unix_sock_path, PATH_MAX,
4072 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
4073 }
4074
4075 /* Set global SHM for ust */
4076 if (strlen(wait_shm_path) == 0) {
4077 snprintf(wait_shm_path, PATH_MAX,
4078 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
4079 }
4080 }
4081
4082 DBG("Client socket path %s", client_unix_sock_path);
4083 DBG("Application socket path %s", apps_unix_sock_path);
4084
4085 /*
4086 * See if daemon already exist.
4087 */
4088 if ((ret = check_existing_daemon()) < 0) {
4089 ERR("Already running daemon.\n");
4090 /*
4091 * We do not goto exit because we must not cleanup()
4092 * because a daemon is already running.
4093 */
4094 goto error;
4095 }
4096
4097 /* After this point, we can safely call cleanup() with "goto exit" */
4098
4099 /*
4100 * These actions must be executed as root. We do that *after* setting up
4101 * the sockets path because we MUST make the check for another daemon using
4102 * those paths *before* trying to set the kernel consumer sockets and init
4103 * kernel tracer.
4104 */
4105 if (is_root) {
4106 ret = set_consumer_sockets(&kconsumer_data);
4107 if (ret < 0) {
4108 goto exit;
4109 }
4110
4111 ret = set_consumer_sockets(&ustconsumer64_data);
4112 if (ret < 0) {
4113 goto exit;
4114 }
4115
4116 ret = set_consumer_sockets(&ustconsumer32_data);
4117 if (ret < 0) {
4118 goto exit;
4119 }
4120
4121 /* Setup kernel tracer */
4122 init_kernel_tracer();
4123
4124 /* Set ulimit for open files */
4125 set_ulimit();
4126 }
4127
4128 if ((ret = set_signal_handler()) < 0) {
4129 goto exit;
4130 }
4131
4132 /* Setup the needed unix socket */
4133 if ((ret = init_daemon_socket()) < 0) {
4134 goto exit;
4135 }
4136
4137 /* Set credentials to socket */
4138 if (is_root && ((ret = set_permissions()) < 0)) {
4139 goto exit;
4140 }
4141
4142 /* Get parent pid if -S, --sig-parent is specified. */
4143 if (opt_sig_parent) {
4144 ppid = getppid();
4145 }
4146
4147 /* Setup the kernel pipe for waking up the kernel thread */
4148 if ((ret = create_kernel_poll_pipe()) < 0) {
4149 goto exit;
4150 }
4151
4152 /* Setup the thread apps communication pipe. */
4153 if ((ret = create_apps_cmd_pipe()) < 0) {
4154 goto exit;
4155 }
4156
4157 /* Init UST command queue. */
4158 cds_wfq_init(&ust_cmd_queue.queue);
4159
4160 /* Init UST app hash table */
4161 ust_app_ht_alloc();
4162
4163 /*
4164 * Get session list pointer. This pointer MUST NOT be free(). This list is
4165 * statically declared in session.c
4166 */
4167 session_list_ptr = session_get_list();
4168
4169 /* Set up max poll set size */
4170 lttng_poll_set_max_size();
4171
4172 /* Create thread to manage the client socket */
4173 ret = pthread_create(&client_thread, NULL,
4174 thread_manage_clients, (void *) NULL);
4175 if (ret != 0) {
4176 perror("pthread_create clients");
4177 goto exit_client;
4178 }
4179
4180 /* Create thread to dispatch registration */
4181 ret = pthread_create(&dispatch_thread, NULL,
4182 thread_dispatch_ust_registration, (void *) NULL);
4183 if (ret != 0) {
4184 perror("pthread_create dispatch");
4185 goto exit_dispatch;
4186 }
4187
4188 /* Create thread to manage application registration. */
4189 ret = pthread_create(&reg_apps_thread, NULL,
4190 thread_registration_apps, (void *) NULL);
4191 if (ret != 0) {
4192 perror("pthread_create registration");
4193 goto exit_reg_apps;
4194 }
4195
4196 /* Create thread to manage application socket */
4197 ret = pthread_create(&apps_thread, NULL,
4198 thread_manage_apps, (void *) NULL);
4199 if (ret != 0) {
4200 perror("pthread_create apps");
4201 goto exit_apps;
4202 }
4203
4204 /* Create kernel thread to manage kernel event */
4205 ret = pthread_create(&kernel_thread, NULL,
4206 thread_manage_kernel, (void *) NULL);
4207 if (ret != 0) {
4208 perror("pthread_create kernel");
4209 goto exit_kernel;
4210 }
4211
4212 ret = pthread_join(kernel_thread, &status);
4213 if (ret != 0) {
4214 perror("pthread_join");
4215 goto error; /* join error, exit without cleanup */
4216 }
4217
4218 exit_kernel:
4219 ret = pthread_join(apps_thread, &status);
4220 if (ret != 0) {
4221 perror("pthread_join");
4222 goto error; /* join error, exit without cleanup */
4223 }
4224
4225 exit_apps:
4226 ret = pthread_join(reg_apps_thread, &status);
4227 if (ret != 0) {
4228 perror("pthread_join");
4229 goto error; /* join error, exit without cleanup */
4230 }
4231
4232 exit_reg_apps:
4233 ret = pthread_join(dispatch_thread, &status);
4234 if (ret != 0) {
4235 perror("pthread_join");
4236 goto error; /* join error, exit without cleanup */
4237 }
4238
4239 exit_dispatch:
4240 ret = pthread_join(client_thread, &status);
4241 if (ret != 0) {
4242 perror("pthread_join");
4243 goto error; /* join error, exit without cleanup */
4244 }
4245
4246 ret = join_consumer_thread(&kconsumer_data);
4247 if (ret != 0) {
4248 perror("join_consumer");
4249 goto error; /* join error, exit without cleanup */
4250 }
4251
4252 exit_client:
4253 exit:
4254 /*
4255 * cleanup() is called when no other thread is running.
4256 */
4257 rcu_thread_online();
4258 cleanup();
4259 rcu_thread_offline();
4260 rcu_unregister_thread();
4261 if (!ret)
4262 exit(EXIT_SUCCESS);
4263 error:
4264 exit(EXIT_FAILURE);
4265 }
LTTng 2.0 tools and control repository
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