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