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