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