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[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 }
1919 break;
1920 }
1921 default:
1922 break;
1923 }
1924 }
1925
1926 /*
1927 * Create a list of ust global domain events.
1928 */
1929 static int list_lttng_ust_global_events(char *channel_name,
1930 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
1931 {
1932 int i = 0, ret = 0;
1933 unsigned int nb_event = 0;
1934 struct cds_lfht_iter iter;
1935 struct ltt_ust_channel *uchan;
1936 struct ltt_ust_event *uevent;
1937 struct lttng_event *tmp;
1938
1939 DBG("Listing UST global events for channel %s", channel_name);
1940
1941 rcu_read_lock();
1942
1943 /* Count events in all channels */
1944 cds_lfht_for_each_entry(ust_global->channels, &iter, uchan, node) {
1945 nb_event += hashtable_get_count(uchan->events);
1946 }
1947
1948 if (nb_event == 0) {
1949 ret = nb_event;
1950 goto error;
1951 }
1952
1953 DBG3("Listing UST global %d events", nb_event);
1954
1955 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
1956 if (tmp == NULL) {
1957 ret = -LTTCOMM_FATAL;
1958 goto error;
1959 }
1960
1961 cds_lfht_for_each_entry(ust_global->channels, &iter, uchan, node) {
1962 cds_lfht_for_each_entry(uchan->events, &iter, uevent, node) {
1963 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
1964 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
1965 tmp[i].enabled = uevent->enabled;
1966 switch (uevent->attr.instrumentation) {
1967 case LTTNG_UST_TRACEPOINT:
1968 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
1969 break;
1970 case LTTNG_UST_PROBE:
1971 tmp[i].type = LTTNG_EVENT_PROBE;
1972 break;
1973 case LTTNG_UST_FUNCTION:
1974 tmp[i].type = LTTNG_EVENT_FUNCTION;
1975 break;
1976 }
1977 i++;
1978 }
1979 }
1980
1981 ret = nb_event;
1982 *events = tmp;
1983
1984 error:
1985 rcu_read_unlock();
1986 return ret;
1987 }
1988
1989 /*
1990 * Fill lttng_event array of all kernel events in the channel.
1991 */
1992 static int list_lttng_kernel_events(char *channel_name,
1993 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
1994 {
1995 int i = 0, ret;
1996 unsigned int nb_event;
1997 struct ltt_kernel_event *event;
1998 struct ltt_kernel_channel *kchan;
1999
2000 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2001 if (kchan == NULL) {
2002 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2003 goto error;
2004 }
2005
2006 nb_event = kchan->event_count;
2007
2008 DBG("Listing events for channel %s", kchan->channel->name);
2009
2010 if (nb_event == 0) {
2011 ret = nb_event;
2012 goto error;
2013 }
2014
2015 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2016 if (*events == NULL) {
2017 ret = LTTCOMM_FATAL;
2018 goto error;
2019 }
2020
2021 /* Kernel channels */
2022 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2023 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2024 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2025 (*events)[i].enabled = event->enabled;
2026 switch (event->event->instrumentation) {
2027 case LTTNG_KERNEL_TRACEPOINT:
2028 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2029 break;
2030 case LTTNG_KERNEL_KPROBE:
2031 case LTTNG_KERNEL_KRETPROBE:
2032 (*events)[i].type = LTTNG_EVENT_PROBE;
2033 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2034 sizeof(struct lttng_kernel_kprobe));
2035 break;
2036 case LTTNG_KERNEL_FUNCTION:
2037 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2038 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2039 sizeof(struct lttng_kernel_function));
2040 break;
2041 case LTTNG_KERNEL_NOOP:
2042 (*events)[i].type = LTTNG_EVENT_NOOP;
2043 break;
2044 case LTTNG_KERNEL_SYSCALL:
2045 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2046 break;
2047 case LTTNG_KERNEL_ALL:
2048 assert(0);
2049 break;
2050 }
2051 i++;
2052 }
2053
2054 return nb_event;
2055
2056 error:
2057 return ret;
2058 }
2059
2060 /*
2061 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2062 */
2063 static int cmd_disable_channel(struct ltt_session *session,
2064 int domain, char *channel_name)
2065 {
2066 int ret;
2067
2068 switch (domain) {
2069 case LTTNG_DOMAIN_KERNEL:
2070 ret = channel_kernel_disable(session->kernel_session,
2071 channel_name);
2072 if (ret != LTTCOMM_OK) {
2073 goto error;
2074 }
2075
2076 kernel_wait_quiescent(kernel_tracer_fd);
2077 break;
2078 case LTTNG_DOMAIN_UST_PID:
2079 break;
2080 default:
2081 ret = LTTCOMM_UNKNOWN_DOMAIN;
2082 goto error;
2083 }
2084
2085 ret = LTTCOMM_OK;
2086
2087 error:
2088 return ret;
2089 }
2090
2091 /*
2092 * Copy channel from attributes and set it in the application channel list.
2093 */
2094 /*
2095 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
2096 struct lttng_channel *attr, struct ust_app *app)
2097 {
2098 int ret;
2099 struct ltt_ust_channel *uchan, *new_chan;
2100
2101 uchan = trace_ust_get_channel_by_key(usess->channels, attr->name);
2102 if (uchan == NULL) {
2103 ret = LTTCOMM_FATAL;
2104 goto error;
2105 }
2106
2107 new_chan = trace_ust_create_channel(attr, usess->path);
2108 if (new_chan == NULL) {
2109 PERROR("malloc ltt_ust_channel");
2110 ret = LTTCOMM_FATAL;
2111 goto error;
2112 }
2113
2114 ret = channel_ust_copy(new_chan, uchan);
2115 if (ret < 0) {
2116 ret = LTTCOMM_FATAL;
2117 goto error;
2118 }
2119
2120 error:
2121 return ret;
2122 }
2123 */
2124
2125 /*
2126 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2127 */
2128 static int cmd_enable_channel(struct ltt_session *session,
2129 struct lttng_domain *domain, struct lttng_channel *attr)
2130 {
2131 int ret;
2132 struct ltt_ust_session *usess = session->ust_session;
2133
2134 DBG("Enabling channel %s for session %s", attr->name, session->name);
2135
2136 switch (domain->type) {
2137 case LTTNG_DOMAIN_KERNEL:
2138 {
2139 struct ltt_kernel_channel *kchan;
2140
2141 kchan = trace_kernel_get_channel_by_name(attr->name,
2142 session->kernel_session);
2143 if (kchan == NULL) {
2144 ret = channel_kernel_create(session->kernel_session,
2145 attr, kernel_poll_pipe[1]);
2146 } else {
2147 ret = channel_kernel_enable(session->kernel_session, kchan);
2148 }
2149
2150 if (ret != LTTCOMM_OK) {
2151 goto error;
2152 }
2153
2154 kernel_wait_quiescent(kernel_tracer_fd);
2155 break;
2156 }
2157 case LTTNG_DOMAIN_UST:
2158 {
2159 struct ltt_ust_channel *uchan;
2160
2161 DBG2("Enabling channel for LTTNG_DOMAIN_UST");
2162
2163 /* Get channel in global UST domain HT */
2164 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2165 attr->name);
2166 if (uchan == NULL) {
2167 uchan = trace_ust_create_channel(attr, usess->pathname);
2168 if (uchan == NULL) {
2169 ret = LTTCOMM_UST_CHAN_FAIL;
2170 goto error;
2171 }
2172
2173 rcu_read_lock();
2174 hashtable_add_unique(usess->domain_global.channels, &uchan->node);
2175 rcu_read_unlock();
2176 DBG2("UST channel %s added to global domain HT", attr->name);
2177 } else {
2178 ret = LTTCOMM_UST_CHAN_EXIST;
2179 goto error;
2180 }
2181
2182 /* Add channel to all registered applications */
2183 ret = ust_app_create_channel_all(usess, uchan);
2184 if (ret != 0) {
2185 goto error;
2186 }
2187
2188 uchan->enabled = 1;
2189
2190 break;
2191 }
2192 case LTTNG_DOMAIN_UST_PID:
2193 {
2194 /*
2195 int sock;
2196 struct ltt_ust_channel *uchan;
2197 struct ltt_ust_session *usess;
2198 struct ust_app *app;
2199
2200 usess = trace_ust_get_session_by_pid(&session->ust_session_list,
2201 domain->attr.pid);
2202 if (usess == NULL) {
2203 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2204 goto error;
2205 }
2206
2207 app = ust_app_get_by_pid(domain->attr.pid);
2208 if (app == NULL) {
2209 ret = LTTCOMM_APP_NOT_FOUND;
2210 goto error;
2211 }
2212 sock = app->sock;
2213
2214 uchan = trace_ust_get_channel_by_name(attr->name, usess);
2215 if (uchan == NULL) {
2216 ret = channel_ust_create(usess, attr, sock);
2217 } else {
2218 ret = channel_ust_enable(usess, uchan, sock);
2219 }
2220
2221 if (ret != LTTCOMM_OK) {
2222 goto error;
2223 }
2224
2225 ret = copy_ust_channel_to_app(usess, attr, app);
2226 if (ret != LTTCOMM_OK) {
2227 goto error;
2228 }
2229
2230 DBG("UST channel %s created for app sock %d with pid %d",
2231 attr->name, app->sock, domain->attr.pid);
2232 */
2233 ret = LTTCOMM_NOT_IMPLEMENTED;
2234 goto error;
2235 }
2236 default:
2237 ret = LTTCOMM_UNKNOWN_DOMAIN;
2238 goto error;
2239 }
2240
2241 ret = LTTCOMM_OK;
2242
2243 error:
2244 return ret;
2245 }
2246
2247 /*
2248 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2249 */
2250 static int cmd_disable_event(struct ltt_session *session, int domain,
2251 char *channel_name, char *event_name)
2252 {
2253 int ret;
2254
2255 switch (domain) {
2256 case LTTNG_DOMAIN_KERNEL:
2257 {
2258 struct ltt_kernel_channel *kchan;
2259
2260 kchan = trace_kernel_get_channel_by_name(channel_name,
2261 session->kernel_session);
2262 if (kchan == NULL) {
2263 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2264 goto error;
2265 }
2266
2267 ret = event_kernel_disable_tracepoint(session->kernel_session, kchan, event_name);
2268 if (ret != LTTCOMM_OK) {
2269 goto error;
2270 }
2271
2272 kernel_wait_quiescent(kernel_tracer_fd);
2273 break;
2274 }
2275 case LTTNG_DOMAIN_UST:
2276 case LTTNG_DOMAIN_UST_EXEC_NAME:
2277 case LTTNG_DOMAIN_UST_PID:
2278 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2279 default:
2280 /* TODO: Other UST domains */
2281 ret = LTTCOMM_NOT_IMPLEMENTED;
2282 goto error;
2283 }
2284
2285 ret = LTTCOMM_OK;
2286
2287 error:
2288 return ret;
2289 }
2290
2291 /*
2292 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2293 */
2294 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2295 char *channel_name)
2296 {
2297 int ret;
2298 struct ltt_kernel_channel *kchan;
2299
2300 switch (domain) {
2301 case LTTNG_DOMAIN_KERNEL:
2302 kchan = trace_kernel_get_channel_by_name(channel_name,
2303 session->kernel_session);
2304 if (kchan == NULL) {
2305 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2306 goto error;
2307 }
2308
2309 ret = event_kernel_disable_all(session->kernel_session, kchan);
2310 if (ret != LTTCOMM_OK) {
2311 goto error;
2312 }
2313
2314 kernel_wait_quiescent(kernel_tracer_fd);
2315 break;
2316 default:
2317 /* TODO: Userspace tracing */
2318 ret = LTTCOMM_NOT_IMPLEMENTED;
2319 goto error;
2320 }
2321
2322 ret = LTTCOMM_OK;
2323
2324 error:
2325 return ret;
2326 }
2327
2328 /*
2329 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2330 */
2331 static int cmd_add_context(struct ltt_session *session, int domain,
2332 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2333 {
2334 int ret;
2335
2336 switch (domain) {
2337 case LTTNG_DOMAIN_KERNEL:
2338 /* Add kernel context to kernel tracer */
2339 ret = context_kernel_add(session->kernel_session, ctx,
2340 event_name, channel_name);
2341 if (ret != LTTCOMM_OK) {
2342 goto error;
2343 }
2344 break;
2345 case LTTNG_DOMAIN_UST:
2346 {
2347 /*
2348 struct ltt_ust_session *usess;
2349
2350 cds_list_for_each_entry(usess, &session->ust_session_list.head, list) {
2351 ret = context_ust_add(usess, ctx,
2352 event_name, channel_name, domain);
2353 if (ret != LTTCOMM_OK) {
2354 goto error;
2355 }
2356 }
2357 break;
2358 */
2359 }
2360 default:
2361 /* TODO: UST other domains */
2362 ret = LTTCOMM_NOT_IMPLEMENTED;
2363 goto error;
2364 }
2365
2366 ret = LTTCOMM_OK;
2367
2368 error:
2369 return ret;
2370 }
2371
2372 /*
2373 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2374 */
2375 static int cmd_enable_event(struct ltt_session *session, int domain,
2376 char *channel_name, struct lttng_event *event)
2377 {
2378 int ret;
2379 struct lttng_channel *attr;
2380 struct ltt_ust_session *usess = session->ust_session;
2381
2382 switch (domain) {
2383 case LTTNG_DOMAIN_KERNEL:
2384 {
2385 struct ltt_kernel_channel *kchan;
2386
2387 kchan = trace_kernel_get_channel_by_name(channel_name,
2388 session->kernel_session);
2389 if (kchan == NULL) {
2390 attr = channel_new_default_attr(domain);
2391 if (attr == NULL) {
2392 ret = LTTCOMM_FATAL;
2393 goto error;
2394 }
2395 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2396
2397 /* This call will notify the kernel thread */
2398 ret = channel_kernel_create(session->kernel_session,
2399 attr, kernel_poll_pipe[1]);
2400 if (ret != LTTCOMM_OK) {
2401 goto error;
2402 }
2403 }
2404
2405 /* Get the newly created kernel channel pointer */
2406 kchan = trace_kernel_get_channel_by_name(channel_name,
2407 session->kernel_session);
2408 if (kchan == NULL) {
2409 /* This sould not happen... */
2410 ret = LTTCOMM_FATAL;
2411 goto error;
2412 }
2413
2414 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2415 event);
2416 if (ret != LTTCOMM_OK) {
2417 goto error;
2418 }
2419
2420 kernel_wait_quiescent(kernel_tracer_fd);
2421 break;
2422 }
2423 case LTTNG_DOMAIN_UST:
2424 {
2425 struct ltt_ust_channel *uchan;
2426 struct ltt_ust_event *uevent;
2427
2428 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2429 channel_name);
2430 if (uchan == NULL) {
2431 /* TODO: Create default channel */
2432 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2433 goto error;
2434 }
2435
2436 uevent = trace_ust_find_event_by_name(uchan->events, event->name);
2437 if (uevent == NULL) {
2438 uevent = trace_ust_create_event(event);
2439 if (uevent == NULL) {
2440 ret = LTTCOMM_FATAL;
2441 goto error;
2442 }
2443
2444 }
2445
2446 ret = ust_app_create_event_all(usess, uchan, uevent);
2447 if (ret < 0) {
2448 ret = LTTCOMM_UST_ENABLE_FAIL;
2449 goto error;
2450 }
2451
2452 /* Add ltt ust event to channel */
2453 rcu_read_lock();
2454 hashtable_add_unique(uchan->events, &uevent->node);
2455 rcu_read_unlock();
2456
2457 uevent->enabled = 1;
2458
2459 DBG3("UST ltt event %s added to channel %s", uevent->attr.name,
2460 uchan->name);
2461 break;
2462 }
2463 case LTTNG_DOMAIN_UST_EXEC_NAME:
2464 case LTTNG_DOMAIN_UST_PID:
2465 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2466 default:
2467 ret = LTTCOMM_NOT_IMPLEMENTED;
2468 goto error;
2469 }
2470
2471 ret = LTTCOMM_OK;
2472
2473 error:
2474 return ret;
2475 }
2476
2477 /*
2478 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2479 */
2480 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2481 char *channel_name, int event_type)
2482 {
2483 int ret;
2484 struct ltt_kernel_channel *kchan;
2485
2486 switch (domain) {
2487 case LTTNG_DOMAIN_KERNEL:
2488 kchan = trace_kernel_get_channel_by_name(channel_name,
2489 session->kernel_session);
2490 if (kchan == NULL) {
2491 /* This call will notify the kernel thread */
2492 ret = channel_kernel_create(session->kernel_session, NULL,
2493 kernel_poll_pipe[1]);
2494 if (ret != LTTCOMM_OK) {
2495 goto error;
2496 }
2497 }
2498
2499 /* Get the newly created kernel channel pointer */
2500 kchan = trace_kernel_get_channel_by_name(channel_name,
2501 session->kernel_session);
2502 if (kchan == NULL) {
2503 /* This sould not happen... */
2504 ret = LTTCOMM_FATAL;
2505 goto error;
2506 }
2507
2508 switch (event_type) {
2509 case LTTNG_KERNEL_SYSCALL:
2510 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2511 kchan, kernel_tracer_fd);
2512 break;
2513 case LTTNG_KERNEL_TRACEPOINT:
2514 /*
2515 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2516 * events already registered to the channel.
2517 */
2518 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2519 kchan, kernel_tracer_fd);
2520 break;
2521 case LTTNG_KERNEL_ALL:
2522 /* Enable syscalls and tracepoints */
2523 ret = event_kernel_enable_all(session->kernel_session,
2524 kchan, kernel_tracer_fd);
2525 break;
2526 default:
2527 ret = LTTCOMM_KERN_ENABLE_FAIL;
2528 goto error;
2529 }
2530 if (ret != LTTCOMM_OK) {
2531 goto error;
2532 }
2533
2534 kernel_wait_quiescent(kernel_tracer_fd);
2535 break;
2536 default:
2537 /* TODO: Userspace tracing */
2538 ret = LTTCOMM_NOT_IMPLEMENTED;
2539 goto error;
2540 }
2541
2542 ret = LTTCOMM_OK;
2543
2544 error:
2545 return ret;
2546 }
2547
2548 /*
2549 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2550 */
2551 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2552 {
2553 int ret;
2554 ssize_t nb_events = 0;
2555
2556 switch (domain) {
2557 case LTTNG_DOMAIN_KERNEL:
2558 nb_events = kernel_list_events(kernel_tracer_fd, events);
2559 if (nb_events < 0) {
2560 ret = LTTCOMM_KERN_LIST_FAIL;
2561 goto error;
2562 }
2563 break;
2564 case LTTNG_DOMAIN_UST:
2565 nb_events = ust_app_list_events(events);
2566 if (nb_events < 0) {
2567 ret = LTTCOMM_UST_LIST_FAIL;
2568 goto error;
2569 }
2570 break;
2571 default:
2572 ret = LTTCOMM_NOT_IMPLEMENTED;
2573 goto error;
2574 }
2575
2576 return nb_events;
2577
2578 error:
2579 /* Return negative value to differentiate return code */
2580 return -ret;
2581 }
2582
2583 /*
2584 * Command LTTNG_START_TRACE processed by the client thread.
2585 */
2586 static int cmd_start_trace(struct ltt_session *session)
2587 {
2588 int ret;
2589 struct ltt_kernel_session *ksession;
2590 struct ltt_ust_session *usess;
2591
2592 /* Short cut */
2593 ksession = session->kernel_session;
2594 usess = session->ust_session;
2595
2596 if (session->enabled)
2597 return LTTCOMM_UST_START_FAIL;
2598 session->enabled = 1;
2599
2600 /* Kernel tracing */
2601 if (ksession != NULL) {
2602 struct ltt_kernel_channel *kchan;
2603
2604 /* Open kernel metadata */
2605 if (ksession->metadata == NULL) {
2606 ret = kernel_open_metadata(ksession, ksession->trace_path);
2607 if (ret < 0) {
2608 ret = LTTCOMM_KERN_META_FAIL;
2609 goto error;
2610 }
2611 }
2612
2613 /* Open kernel metadata stream */
2614 if (ksession->metadata_stream_fd == 0) {
2615 ret = kernel_open_metadata_stream(ksession);
2616 if (ret < 0) {
2617 ERR("Kernel create metadata stream failed");
2618 ret = LTTCOMM_KERN_STREAM_FAIL;
2619 goto error;
2620 }
2621 }
2622
2623 /* For each channel */
2624 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2625 if (kchan->stream_count == 0) {
2626 ret = kernel_open_channel_stream(kchan);
2627 if (ret < 0) {
2628 ret = LTTCOMM_KERN_STREAM_FAIL;
2629 goto error;
2630 }
2631 /* Update the stream global counter */
2632 ksession->stream_count_global += ret;
2633 }
2634 }
2635
2636 /* Setup kernel consumer socket and send fds to it */
2637 ret = init_kernel_tracing(ksession);
2638 if (ret < 0) {
2639 ret = LTTCOMM_KERN_START_FAIL;
2640 goto error;
2641 }
2642
2643 /* This start the kernel tracing */
2644 ret = kernel_start_session(ksession);
2645 if (ret < 0) {
2646 ret = LTTCOMM_KERN_START_FAIL;
2647 goto error;
2648 }
2649
2650 /* Quiescent wait after starting trace */
2651 kernel_wait_quiescent(kernel_tracer_fd);
2652 }
2653
2654 /* Flag session that trace should start automatically */
2655 if (usess) {
2656 usess->start_trace = 1;
2657
2658 ret = ust_app_start_trace_all(usess);
2659 if (ret < 0) {
2660 ret = LTTCOMM_UST_START_FAIL;
2661 goto error;
2662 }
2663 }
2664
2665 ret = LTTCOMM_OK;
2666
2667 error:
2668 return ret;
2669 }
2670
2671 /*
2672 * Command LTTNG_STOP_TRACE processed by the client thread.
2673 */
2674 static int cmd_stop_trace(struct ltt_session *session)
2675 {
2676 int ret;
2677 struct ltt_kernel_channel *kchan;
2678 struct ltt_kernel_session *ksession;
2679 struct ltt_ust_session *usess;
2680
2681 /* Short cut */
2682 ksession = session->kernel_session;
2683 usess = session->ust_session;
2684
2685 if (!session->enabled)
2686 return LTTCOMM_UST_START_FAIL;
2687 session->enabled = 0;
2688
2689 /* Kernel tracer */
2690 if (ksession != NULL) {
2691 DBG("Stop kernel tracing");
2692
2693 /* Flush all buffers before stopping */
2694 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2695 if (ret < 0) {
2696 ERR("Kernel metadata flush failed");
2697 }
2698
2699 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2700 ret = kernel_flush_buffer(kchan);
2701 if (ret < 0) {
2702 ERR("Kernel flush buffer error");
2703 }
2704 }
2705
2706 ret = kernel_stop_session(ksession);
2707 if (ret < 0) {
2708 ret = LTTCOMM_KERN_STOP_FAIL;
2709 goto error;
2710 }
2711
2712 kernel_wait_quiescent(kernel_tracer_fd);
2713 }
2714
2715 /* Flag session that trace should start automatically */
2716 if (usess) {
2717 usess->start_trace = 0;
2718
2719 ret = ust_app_stop_trace_all(usess);
2720 if (ret < 0) {
2721 ret = LTTCOMM_UST_START_FAIL;
2722 goto error;
2723 }
2724 }
2725
2726 ret = LTTCOMM_OK;
2727
2728 error:
2729 return ret;
2730 }
2731
2732 /*
2733 * Command LTTNG_CREATE_SESSION processed by the client thread.
2734 */
2735 static int cmd_create_session(char *name, char *path)
2736 {
2737 int ret;
2738
2739 ret = session_create(name, path);
2740 if (ret != LTTCOMM_OK) {
2741 goto error;
2742 }
2743
2744 ret = LTTCOMM_OK;
2745
2746 error:
2747 return ret;
2748 }
2749
2750 /*
2751 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2752 */
2753 static int cmd_destroy_session(struct ltt_session *session, char *name)
2754 {
2755 int ret;
2756
2757 /* Clean kernel session teardown */
2758 teardown_kernel_session(session);
2759 /* UST session teardown */
2760 teardown_ust_session(session);
2761
2762 /*
2763 * Must notify the kernel thread here to update it's poll setin order
2764 * to remove the channel(s)' fd just destroyed.
2765 */
2766 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2767 if (ret < 0) {
2768 perror("write kernel poll pipe");
2769 }
2770
2771 ret = session_destroy(session);
2772
2773 return ret;
2774 }
2775
2776 /*
2777 * Command LTTNG_CALIBRATE processed by the client thread.
2778 */
2779 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2780 {
2781 int ret;
2782
2783 switch (domain) {
2784 case LTTNG_DOMAIN_KERNEL:
2785 {
2786 struct lttng_kernel_calibrate kcalibrate;
2787
2788 kcalibrate.type = calibrate->type;
2789 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2790 if (ret < 0) {
2791 ret = LTTCOMM_KERN_ENABLE_FAIL;
2792 goto error;
2793 }
2794 break;
2795 }
2796 default:
2797 /* TODO: Userspace tracing */
2798 ret = LTTCOMM_NOT_IMPLEMENTED;
2799 goto error;
2800 }
2801
2802 ret = LTTCOMM_OK;
2803
2804 error:
2805 return ret;
2806 }
2807
2808 /*
2809 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2810 */
2811 static int cmd_register_consumer(struct ltt_session *session, int domain,
2812 char *sock_path)
2813 {
2814 int ret, sock;
2815
2816 switch (domain) {
2817 case LTTNG_DOMAIN_KERNEL:
2818 /* Can't register a consumer if there is already one */
2819 if (session->kernel_session->consumer_fd != 0) {
2820 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2821 goto error;
2822 }
2823
2824 sock = lttcomm_connect_unix_sock(sock_path);
2825 if (sock < 0) {
2826 ret = LTTCOMM_CONNECT_FAIL;
2827 goto error;
2828 }
2829
2830 session->kernel_session->consumer_fd = sock;
2831 break;
2832 default:
2833 /* TODO: Userspace tracing */
2834 ret = LTTCOMM_NOT_IMPLEMENTED;
2835 goto error;
2836 }
2837
2838 ret = LTTCOMM_OK;
2839
2840 error:
2841 return ret;
2842 }
2843
2844 /*
2845 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2846 */
2847 static ssize_t cmd_list_domains(struct ltt_session *session,
2848 struct lttng_domain **domains)
2849 {
2850 int ret, index = 0;
2851 ssize_t nb_dom = 0;
2852
2853 if (session->kernel_session != NULL) {
2854 DBG3("Listing domains found kernel domain");
2855 nb_dom++;
2856 }
2857
2858 if (session->ust_session != NULL) {
2859 DBG3("Listing domains found UST global domain");
2860 nb_dom++;
2861 }
2862
2863 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
2864 if (*domains == NULL) {
2865 ret = -LTTCOMM_FATAL;
2866 goto error;
2867 }
2868
2869 if (session->kernel_session != NULL) {
2870 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
2871 index++;
2872 }
2873
2874 if (session->ust_session != NULL) {
2875 (*domains)[index].type = LTTNG_DOMAIN_UST;
2876 index++;
2877 }
2878
2879 return nb_dom;
2880
2881 error:
2882 return ret;
2883 }
2884
2885 /*
2886 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2887 */
2888 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
2889 struct lttng_channel **channels)
2890 {
2891 int ret;
2892 ssize_t nb_chan = 0;
2893
2894 switch (domain) {
2895 case LTTNG_DOMAIN_KERNEL:
2896 if (session->kernel_session != NULL) {
2897 nb_chan = session->kernel_session->channel_count;
2898 }
2899 DBG3("Number of kernel channels %zd", nb_chan);
2900 break;
2901 case LTTNG_DOMAIN_UST:
2902 if (session->ust_session != NULL) {
2903 nb_chan = hashtable_get_count(
2904 session->ust_session->domain_global.channels);
2905 }
2906 DBG3("Number of UST global channels %zd", nb_chan);
2907 break;
2908 default:
2909 *channels = NULL;
2910 ret = -LTTCOMM_NOT_IMPLEMENTED;
2911 goto error;
2912 }
2913
2914 if (nb_chan > 0) {
2915 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
2916 if (*channels == NULL) {
2917 ret = -LTTCOMM_FATAL;
2918 goto error;
2919 }
2920
2921 list_lttng_channels(domain, session, *channels);
2922 } else {
2923 *channels = NULL;
2924 }
2925
2926 return nb_chan;
2927
2928 error:
2929 return ret;
2930 }
2931
2932 /*
2933 * Command LTTNG_LIST_EVENTS processed by the client thread.
2934 */
2935 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
2936 char *channel_name, struct lttng_event **events)
2937 {
2938 int ret = 0;
2939 ssize_t nb_event = 0;
2940
2941 switch (domain) {
2942 case LTTNG_DOMAIN_KERNEL:
2943 if (session->kernel_session != NULL) {
2944 nb_event = list_lttng_kernel_events(channel_name,
2945 session->kernel_session, events);
2946 }
2947 break;
2948 case LTTNG_DOMAIN_UST:
2949 {
2950 if (session->ust_session != NULL) {
2951 nb_event = list_lttng_ust_global_events(channel_name,
2952 &session->ust_session->domain_global, events);
2953 }
2954 break;
2955 }
2956 default:
2957 ret = -LTTCOMM_NOT_IMPLEMENTED;
2958 goto error;
2959 }
2960
2961 ret = nb_event;
2962
2963 error:
2964 return ret;
2965 }
2966
2967 /*
2968 * Process the command requested by the lttng client within the command
2969 * context structure. This function make sure that the return structure (llm)
2970 * is set and ready for transmission before returning.
2971 *
2972 * Return any error encountered or 0 for success.
2973 */
2974 static int process_client_msg(struct command_ctx *cmd_ctx)
2975 {
2976 int ret = LTTCOMM_OK;
2977 int need_tracing_session = 1;
2978
2979 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
2980
2981 /*
2982 * Check for command that don't needs to allocate a returned payload. We do
2983 * this here so we don't have to make the call for no payload at each
2984 * command.
2985 */
2986 switch(cmd_ctx->lsm->cmd_type) {
2987 case LTTNG_LIST_SESSIONS:
2988 case LTTNG_LIST_TRACEPOINTS:
2989 case LTTNG_LIST_DOMAINS:
2990 case LTTNG_LIST_CHANNELS:
2991 case LTTNG_LIST_EVENTS:
2992 break;
2993 default:
2994 /* Setup lttng message with no payload */
2995 ret = setup_lttng_msg(cmd_ctx, 0);
2996 if (ret < 0) {
2997 /* This label does not try to unlock the session */
2998 goto init_setup_error;
2999 }
3000 }
3001
3002 /* Commands that DO NOT need a session. */
3003 switch (cmd_ctx->lsm->cmd_type) {
3004 case LTTNG_CALIBRATE:
3005 case LTTNG_CREATE_SESSION:
3006 case LTTNG_LIST_SESSIONS:
3007 case LTTNG_LIST_TRACEPOINTS:
3008 need_tracing_session = 0;
3009 break;
3010 default:
3011 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3012 session_lock_list();
3013 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3014 session_unlock_list();
3015 if (cmd_ctx->session == NULL) {
3016 if (cmd_ctx->lsm->session.name != NULL) {
3017 ret = LTTCOMM_SESS_NOT_FOUND;
3018 } else {
3019 /* If no session name specified */
3020 ret = LTTCOMM_SELECT_SESS;
3021 }
3022 goto error;
3023 } else {
3024 /* Acquire lock for the session */
3025 session_lock(cmd_ctx->session);
3026 }
3027 break;
3028 }
3029
3030 /*
3031 * Check domain type for specific "pre-action".
3032 */
3033 switch (cmd_ctx->lsm->domain.type) {
3034 case LTTNG_DOMAIN_KERNEL:
3035 /* Kernel tracer check */
3036 if (kernel_tracer_fd == 0) {
3037 /* Basically, load kernel tracer modules */
3038 init_kernel_tracer();
3039 if (kernel_tracer_fd == 0) {
3040 ret = LTTCOMM_KERN_NA;
3041 goto error;
3042 }
3043 }
3044
3045 /* Need a session for kernel command */
3046 if (need_tracing_session) {
3047 if (cmd_ctx->session->kernel_session == NULL) {
3048 ret = create_kernel_session(cmd_ctx->session);
3049 if (ret < 0) {
3050 ret = LTTCOMM_KERN_SESS_FAIL;
3051 goto error;
3052 }
3053 }
3054
3055 /* Start the kernel consumer daemon */
3056 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3057 if (kconsumer_data.pid == 0 &&
3058 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3059 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3060 ret = start_consumerd(&kconsumer_data);
3061 if (ret < 0) {
3062 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3063 goto error;
3064 }
3065 } else {
3066 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3067 }
3068 }
3069 break;
3070 case LTTNG_DOMAIN_UST:
3071 {
3072 if (need_tracing_session) {
3073 if (cmd_ctx->session->ust_session == NULL) {
3074 ret = create_ust_session(cmd_ctx->session,
3075 &cmd_ctx->lsm->domain);
3076 if (ret != LTTCOMM_OK) {
3077 goto error;
3078 }
3079 }
3080 /* Start the UST consumer daemons */
3081 /* 64-bit */
3082 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3083 if (consumerd64_bindir[0] != '\0' &&
3084 ustconsumer64_data.pid == 0 &&
3085 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3086 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3087 ret = start_consumerd(&ustconsumer64_data);
3088 if (ret < 0) {
3089 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3090 ust_consumerd64_fd = -EINVAL;
3091 goto error;
3092 }
3093
3094 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3095 } else {
3096 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3097 }
3098 /* 32-bit */
3099 if (consumerd32_bindir[0] != '\0' &&
3100 ustconsumer32_data.pid == 0 &&
3101 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3102 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3103 ret = start_consumerd(&ustconsumer32_data);
3104 if (ret < 0) {
3105 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3106 ust_consumerd32_fd = -EINVAL;
3107 goto error;
3108 }
3109 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3110 } else {
3111 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3112 }
3113 }
3114 break;
3115 }
3116 default:
3117 break;
3118 }
3119
3120 /* Process by command type */
3121 switch (cmd_ctx->lsm->cmd_type) {
3122 case LTTNG_ADD_CONTEXT:
3123 {
3124 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3125 cmd_ctx->lsm->u.context.channel_name,
3126 cmd_ctx->lsm->u.context.event_name,
3127 &cmd_ctx->lsm->u.context.ctx);
3128 break;
3129 }
3130 case LTTNG_DISABLE_CHANNEL:
3131 {
3132 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3133 cmd_ctx->lsm->u.disable.channel_name);
3134 break;
3135 }
3136 case LTTNG_DISABLE_EVENT:
3137 {
3138 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3139 cmd_ctx->lsm->u.disable.channel_name,
3140 cmd_ctx->lsm->u.disable.name);
3141 ret = LTTCOMM_OK;
3142 break;
3143 }
3144 case LTTNG_DISABLE_ALL_EVENT:
3145 {
3146 DBG("Disabling all events");
3147
3148 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3149 cmd_ctx->lsm->u.disable.channel_name);
3150 break;
3151 }
3152 case LTTNG_ENABLE_CHANNEL:
3153 {
3154 ret = cmd_enable_channel(cmd_ctx->session, &cmd_ctx->lsm->domain,
3155 &cmd_ctx->lsm->u.channel.chan);
3156 break;
3157 }
3158 case LTTNG_ENABLE_EVENT:
3159 {
3160 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3161 cmd_ctx->lsm->u.enable.channel_name,
3162 &cmd_ctx->lsm->u.enable.event);
3163 break;
3164 }
3165 case LTTNG_ENABLE_ALL_EVENT:
3166 {
3167 DBG("Enabling all events");
3168
3169 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3170 cmd_ctx->lsm->u.enable.channel_name,
3171 cmd_ctx->lsm->u.enable.event.type);
3172 break;
3173 }
3174 case LTTNG_LIST_TRACEPOINTS:
3175 {
3176 struct lttng_event *events;
3177 ssize_t nb_events;
3178
3179 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3180 if (nb_events < 0) {
3181 ret = -nb_events;
3182 goto error;
3183 }
3184
3185 /*
3186 * Setup lttng message with payload size set to the event list size in
3187 * bytes and then copy list into the llm payload.
3188 */
3189 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3190 if (ret < 0) {
3191 free(events);
3192 goto setup_error;
3193 }
3194
3195 /* Copy event list into message payload */
3196 memcpy(cmd_ctx->llm->payload, events,
3197 sizeof(struct lttng_event) * nb_events);
3198
3199 free(events);
3200
3201 ret = LTTCOMM_OK;
3202 break;
3203 }
3204 case LTTNG_START_TRACE:
3205 {
3206 ret = cmd_start_trace(cmd_ctx->session);
3207 break;
3208 }
3209 case LTTNG_STOP_TRACE:
3210 {
3211 ret = cmd_stop_trace(cmd_ctx->session);
3212 break;
3213 }
3214 case LTTNG_CREATE_SESSION:
3215 {
3216 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3217 cmd_ctx->lsm->session.path);
3218 break;
3219 }
3220 case LTTNG_DESTROY_SESSION:
3221 {
3222 ret = cmd_destroy_session(cmd_ctx->session,
3223 cmd_ctx->lsm->session.name);
3224 break;
3225 }
3226 case LTTNG_LIST_DOMAINS:
3227 {
3228 ssize_t nb_dom;
3229 struct lttng_domain *domains;
3230
3231 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3232 if (nb_dom < 0) {
3233 ret = -nb_dom;
3234 goto error;
3235 }
3236
3237 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3238 if (ret < 0) {
3239 goto setup_error;
3240 }
3241
3242 /* Copy event list into message payload */
3243 memcpy(cmd_ctx->llm->payload, domains,
3244 nb_dom * sizeof(struct lttng_domain));
3245
3246 free(domains);
3247
3248 ret = LTTCOMM_OK;
3249 break;
3250 }
3251 case LTTNG_LIST_CHANNELS:
3252 {
3253 size_t nb_chan;
3254 struct lttng_channel *channels;
3255
3256 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
3257 cmd_ctx->session, &channels);
3258 if (nb_chan < 0) {
3259 ret = -nb_chan;
3260 goto error;
3261 }
3262
3263 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3264 if (ret < 0) {
3265 goto setup_error;
3266 }
3267
3268 /* Copy event list into message payload */
3269 memcpy(cmd_ctx->llm->payload, channels,
3270 nb_chan * sizeof(struct lttng_channel));
3271
3272 free(channels);
3273
3274 ret = LTTCOMM_OK;
3275 break;
3276 }
3277 case LTTNG_LIST_EVENTS:
3278 {
3279 ssize_t nb_event;
3280 struct lttng_event *events = NULL;
3281
3282 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
3283 cmd_ctx->lsm->u.list.channel_name, &events);
3284 if (nb_event < 0) {
3285 ret = -nb_event;
3286 goto error;
3287 }
3288
3289 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3290 if (ret < 0) {
3291 goto setup_error;
3292 }
3293
3294 /* Copy event list into message payload */
3295 memcpy(cmd_ctx->llm->payload, events,
3296 nb_event * sizeof(struct lttng_event));
3297
3298 free(events);
3299
3300 ret = LTTCOMM_OK;
3301 break;
3302 }
3303 case LTTNG_LIST_SESSIONS:
3304 {
3305 session_lock_list();
3306
3307 if (session_list_ptr->count == 0) {
3308 ret = LTTCOMM_NO_SESSION;
3309 session_unlock_list();
3310 goto error;
3311 }
3312
3313 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) *
3314 session_list_ptr->count);
3315 if (ret < 0) {
3316 session_unlock_list();
3317 goto setup_error;
3318 }
3319
3320 /* Filled the session array */
3321 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
3322
3323 session_unlock_list();
3324
3325 ret = LTTCOMM_OK;
3326 break;
3327 }
3328 case LTTNG_CALIBRATE:
3329 {
3330 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3331 &cmd_ctx->lsm->u.calibrate);
3332 break;
3333 }
3334 case LTTNG_REGISTER_CONSUMER:
3335 {
3336 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3337 cmd_ctx->lsm->u.reg.path);
3338 break;
3339 }
3340 default:
3341 ret = LTTCOMM_UND;
3342 break;
3343 }
3344
3345 error:
3346 if (cmd_ctx->llm == NULL) {
3347 DBG("Missing llm structure. Allocating one.");
3348 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3349 goto setup_error;
3350 }
3351 }
3352 /* Set return code */
3353 cmd_ctx->llm->ret_code = ret;
3354 setup_error:
3355 if (cmd_ctx->session) {
3356 session_unlock(cmd_ctx->session);
3357 }
3358 init_setup_error:
3359 return ret;
3360 }
3361
3362 /*
3363 * This thread manage all clients request using the unix client socket for
3364 * communication.
3365 */
3366 static void *thread_manage_clients(void *data)
3367 {
3368 int sock = 0, ret, i, pollfd;
3369 uint32_t revents, nb_fd;
3370 struct command_ctx *cmd_ctx = NULL;
3371 struct lttng_poll_event events;
3372
3373 DBG("[thread] Manage client started");
3374
3375 rcu_register_thread();
3376
3377 ret = lttcomm_listen_unix_sock(client_sock);
3378 if (ret < 0) {
3379 goto error;
3380 }
3381
3382 /*
3383 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3384 * more will be added to this poll set.
3385 */
3386 ret = create_thread_poll_set(&events, 2);
3387 if (ret < 0) {
3388 goto error;
3389 }
3390
3391 /* Add the application registration socket */
3392 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3393 if (ret < 0) {
3394 goto error;
3395 }
3396
3397 /*
3398 * Notify parent pid that we are ready to accept command for client side.
3399 */
3400 if (opt_sig_parent) {
3401 kill(ppid, SIGCHLD);
3402 }
3403
3404 while (1) {
3405 DBG("Accepting client command ...");
3406
3407 nb_fd = LTTNG_POLL_GETNB(&events);
3408
3409 /* Inifinite blocking call, waiting for transmission */
3410 ret = lttng_poll_wait(&events, -1);
3411 if (ret < 0) {
3412 goto error;
3413 }
3414
3415 for (i = 0; i < nb_fd; i++) {
3416 /* Fetch once the poll data */
3417 revents = LTTNG_POLL_GETEV(&events, i);
3418 pollfd = LTTNG_POLL_GETFD(&events, i);
3419
3420 /* Thread quit pipe has been closed. Killing thread. */
3421 ret = check_thread_quit_pipe(pollfd, revents);
3422 if (ret) {
3423 goto error;
3424 }
3425
3426 /* Event on the registration socket */
3427 if (pollfd == client_sock) {
3428 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3429 ERR("Client socket poll error");
3430 goto error;
3431 }
3432 }
3433 }
3434
3435 DBG("Wait for client response");
3436
3437 sock = lttcomm_accept_unix_sock(client_sock);
3438 if (sock < 0) {
3439 goto error;
3440 }
3441
3442 /* Allocate context command to process the client request */
3443 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3444 if (cmd_ctx == NULL) {
3445 perror("zmalloc cmd_ctx");
3446 goto error;
3447 }
3448
3449 /* Allocate data buffer for reception */
3450 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3451 if (cmd_ctx->lsm == NULL) {
3452 perror("zmalloc cmd_ctx->lsm");
3453 goto error;
3454 }
3455
3456 cmd_ctx->llm = NULL;
3457 cmd_ctx->session = NULL;
3458
3459 /*
3460 * Data is received from the lttng client. The struct
3461 * lttcomm_session_msg (lsm) contains the command and data request of
3462 * the client.
3463 */
3464 DBG("Receiving data from client ...");
3465 ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm,
3466 sizeof(struct lttcomm_session_msg));
3467 if (ret <= 0) {
3468 DBG("Nothing recv() from client... continuing");
3469 close(sock);
3470 free(cmd_ctx);
3471 continue;
3472 }
3473
3474 // TODO: Validate cmd_ctx including sanity check for
3475 // security purpose.
3476
3477 rcu_thread_online();
3478 /*
3479 * This function dispatch the work to the kernel or userspace tracer
3480 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3481 * informations for the client. The command context struct contains
3482 * everything this function may needs.
3483 */
3484 ret = process_client_msg(cmd_ctx);
3485 rcu_thread_offline();
3486 if (ret < 0) {
3487 /*
3488 * TODO: Inform client somehow of the fatal error. At
3489 * this point, ret < 0 means that a zmalloc failed
3490 * (ENOMEM). Error detected but still accept command.
3491 */
3492 clean_command_ctx(&cmd_ctx);
3493 continue;
3494 }
3495
3496 DBG("Sending response (size: %d, retcode: %s)",
3497 cmd_ctx->lttng_msg_size,
3498 lttng_strerror(-cmd_ctx->llm->ret_code));
3499 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3500 if (ret < 0) {
3501 ERR("Failed to send data back to client");
3502 }
3503
3504 clean_command_ctx(&cmd_ctx);
3505
3506 /* End of transmission */
3507 close(sock);
3508 }
3509
3510 error:
3511 DBG("Client thread dying");
3512 unlink(client_unix_sock_path);
3513 close(client_sock);
3514 close(sock);
3515
3516 lttng_poll_clean(&events);
3517 clean_command_ctx(&cmd_ctx);
3518
3519 rcu_unregister_thread();
3520 return NULL;
3521 }
3522
3523
3524 /*
3525 * usage function on stderr
3526 */
3527 static void usage(void)
3528 {
3529 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3530 fprintf(stderr, " -h, --help Display this usage.\n");
3531 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3532 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3533 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3534 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3535 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
3536 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
3537 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
3538 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
3539 fprintf(stderr, " --ustconsumerd32 PATH Specify path for the 32-bit UST consumer daemon binary\n");
3540 fprintf(stderr, " --ustconsumerd64 PATH Specify path for the 64-bit UST consumer daemon binary\n");
3541 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3542 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3543 fprintf(stderr, " -V, --version Show version number.\n");
3544 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3545 fprintf(stderr, " -q, --quiet No output at all.\n");
3546 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3547 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3548 }
3549
3550 /*
3551 * daemon argument parsing
3552 */
3553 static int parse_args(int argc, char **argv)
3554 {
3555 int c;
3556
3557 static struct option long_options[] = {
3558 { "client-sock", 1, 0, 'c' },
3559 { "apps-sock", 1, 0, 'a' },
3560 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3561 { "kconsumerd-err-sock", 1, 0, 'E' },
3562 { "ustconsumerd64", 1, 0, 't' },
3563 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
3564 { "ustconsumerd64-err-sock", 1, 0, 'F' },
3565 { "ustconsumerd32", 1, 0, 'u' },
3566 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
3567 { "ustconsumerd32-err-sock", 1, 0, 'H' },
3568 { "daemonize", 0, 0, 'd' },
3569 { "sig-parent", 0, 0, 'S' },
3570 { "help", 0, 0, 'h' },
3571 { "group", 1, 0, 'g' },
3572 { "version", 0, 0, 'V' },
3573 { "quiet", 0, 0, 'q' },
3574 { "verbose", 0, 0, 'v' },
3575 { "verbose-consumer", 0, 0, 'Z' },
3576 { NULL, 0, 0, 0 }
3577 };
3578
3579 while (1) {
3580 int option_index = 0;
3581 c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:C:E:D:F:Z:u:t",
3582 long_options, &option_index);
3583 if (c == -1) {
3584 break;
3585 }
3586
3587 switch (c) {
3588 case 0:
3589 fprintf(stderr, "option %s", long_options[option_index].name);
3590 if (optarg) {
3591 fprintf(stderr, " with arg %s\n", optarg);
3592 }
3593 break;
3594 case 'c':
3595 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3596 break;
3597 case 'a':
3598 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3599 break;
3600 case 'd':
3601 opt_daemon = 1;
3602 break;
3603 case 'g':
3604 opt_tracing_group = optarg;
3605 break;
3606 case 'h':
3607 usage();
3608 exit(EXIT_FAILURE);
3609 case 'V':
3610 fprintf(stdout, "%s\n", VERSION);
3611 exit(EXIT_SUCCESS);
3612 case 'S':
3613 opt_sig_parent = 1;
3614 break;
3615 case 'E':
3616 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3617 break;
3618 case 'C':
3619 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3620 break;
3621 case 'F':
3622 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3623 break;
3624 case 'D':
3625 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3626 break;
3627 case 'H':
3628 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3629 break;
3630 case 'G':
3631 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3632 break;
3633 case 'q':
3634 opt_quiet = 1;
3635 break;
3636 case 'v':
3637 /* Verbose level can increase using multiple -v */
3638 opt_verbose += 1;
3639 break;
3640 case 'Z':
3641 opt_verbose_consumer += 1;
3642 break;
3643 case 'u':
3644 consumerd32_bindir = optarg;
3645 break;
3646 case 't':
3647 consumerd64_bindir = optarg;
3648 break;
3649 default:
3650 /* Unknown option or other error.
3651 * Error is printed by getopt, just return */
3652 return -1;
3653 }
3654 }
3655
3656 return 0;
3657 }
3658
3659 /*
3660 * Creates the two needed socket by the daemon.
3661 * apps_sock - The communication socket for all UST apps.
3662 * client_sock - The communication of the cli tool (lttng).
3663 */
3664 static int init_daemon_socket(void)
3665 {
3666 int ret = 0;
3667 mode_t old_umask;
3668
3669 old_umask = umask(0);
3670
3671 /* Create client tool unix socket */
3672 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3673 if (client_sock < 0) {
3674 ERR("Create unix sock failed: %s", client_unix_sock_path);
3675 ret = -1;
3676 goto end;
3677 }
3678
3679 /* File permission MUST be 660 */
3680 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3681 if (ret < 0) {
3682 ERR("Set file permissions failed: %s", client_unix_sock_path);
3683 perror("chmod");
3684 goto end;
3685 }
3686
3687 /* Create the application unix socket */
3688 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3689 if (apps_sock < 0) {
3690 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3691 ret = -1;
3692 goto end;
3693 }
3694
3695 /* File permission MUST be 666 */
3696 ret = chmod(apps_unix_sock_path,
3697 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3698 if (ret < 0) {
3699 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3700 perror("chmod");
3701 goto end;
3702 }
3703
3704 end:
3705 umask(old_umask);
3706 return ret;
3707 }
3708
3709 /*
3710 * Check if the global socket is available, and if a daemon is answering at the
3711 * other side. If yes, error is returned.
3712 */
3713 static int check_existing_daemon(void)
3714 {
3715 if (access(client_unix_sock_path, F_OK) < 0 &&
3716 access(apps_unix_sock_path, F_OK) < 0) {
3717 return 0;
3718 }
3719
3720 /* Is there anybody out there ? */
3721 if (lttng_session_daemon_alive()) {
3722 return -EEXIST;
3723 } else {
3724 return 0;
3725 }
3726 }
3727
3728 /*
3729 * Set the tracing group gid onto the client socket.
3730 *
3731 * Race window between mkdir and chown is OK because we are going from more
3732 * permissive (root.root) to les permissive (root.tracing).
3733 */
3734 static int set_permissions(void)
3735 {
3736 int ret;
3737 gid_t gid;
3738
3739 gid = allowed_group();
3740 if (gid < 0) {
3741 if (is_root) {
3742 WARN("No tracing group detected");
3743 ret = 0;
3744 } else {
3745 ERR("Missing tracing group. Aborting execution.");
3746 ret = -1;
3747 }
3748 goto end;
3749 }
3750
3751 /* Set lttng run dir */
3752 ret = chown(LTTNG_RUNDIR, 0, gid);
3753 if (ret < 0) {
3754 ERR("Unable to set group on " LTTNG_RUNDIR);
3755 perror("chown");
3756 }
3757
3758 /* lttng client socket path */
3759 ret = chown(client_unix_sock_path, 0, gid);
3760 if (ret < 0) {
3761 ERR("Unable to set group on %s", client_unix_sock_path);
3762 perror("chown");
3763 }
3764
3765 /* kconsumer error socket path */
3766 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
3767 if (ret < 0) {
3768 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
3769 perror("chown");
3770 }
3771
3772 /* 64-bit ustconsumer error socket path */
3773 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
3774 if (ret < 0) {
3775 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
3776 perror("chown");
3777 }
3778
3779 /* 32-bit ustconsumer compat32 error socket path */
3780 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
3781 if (ret < 0) {
3782 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
3783 perror("chown");
3784 }
3785
3786 DBG("All permissions are set");
3787
3788 end:
3789 return ret;
3790 }
3791
3792 /*
3793 * Create the pipe used to wake up the kernel thread.
3794 */
3795 static int create_kernel_poll_pipe(void)
3796 {
3797 return pipe2(kernel_poll_pipe, O_CLOEXEC);
3798 }
3799
3800 /*
3801 * Create the application command pipe to wake thread_manage_apps.
3802 */
3803 static int create_apps_cmd_pipe(void)
3804 {
3805 return pipe2(apps_cmd_pipe, O_CLOEXEC);
3806 }
3807
3808 /*
3809 * Create the lttng run directory needed for all global sockets and pipe.
3810 */
3811 static int create_lttng_rundir(void)
3812 {
3813 int ret;
3814
3815 ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG );
3816 if (ret < 0) {
3817 if (errno != EEXIST) {
3818 ERR("Unable to create " LTTNG_RUNDIR);
3819 goto error;
3820 } else {
3821 ret = 0;
3822 }
3823 }
3824
3825 error:
3826 return ret;
3827 }
3828
3829 /*
3830 * Setup sockets and directory needed by the kconsumerd communication with the
3831 * session daemon.
3832 */
3833 static int set_consumer_sockets(struct consumer_data *consumer_data)
3834 {
3835 int ret;
3836 const char *path;
3837
3838 switch (consumer_data->type) {
3839 case LTTNG_CONSUMER_KERNEL:
3840 path = KCONSUMERD_PATH;
3841 break;
3842 case LTTNG_CONSUMER64_UST:
3843 path = USTCONSUMERD64_PATH;
3844 break;
3845 case LTTNG_CONSUMER32_UST:
3846 path = USTCONSUMERD32_PATH;
3847 break;
3848 default:
3849 ERR("Consumer type unknown");
3850 ret = -EINVAL;
3851 goto error;
3852 }
3853
3854 ret = mkdir(path, S_IRWXU | S_IRWXG);
3855 if (ret < 0) {
3856 if (errno != EEXIST) {
3857 ERR("Failed to create %s", path);
3858 goto error;
3859 }
3860 ret = 0;
3861 }
3862
3863 /* Create the kconsumerd error unix socket */
3864 consumer_data->err_sock =
3865 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
3866 if (consumer_data->err_sock < 0) {
3867 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
3868 ret = -1;
3869 goto error;
3870 }
3871
3872 /* File permission MUST be 660 */
3873 ret = chmod(consumer_data->err_unix_sock_path,
3874 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3875 if (ret < 0) {
3876 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
3877 perror("chmod");
3878 goto error;
3879 }
3880
3881 error:
3882 return ret;
3883 }
3884
3885 /*
3886 * Signal handler for the daemon
3887 *
3888 * Simply stop all worker threads, leaving main() return gracefully after
3889 * joining all threads and calling cleanup().
3890 */
3891 static void sighandler(int sig)
3892 {
3893 switch (sig) {
3894 case SIGPIPE:
3895 DBG("SIGPIPE catched");
3896 return;
3897 case SIGINT:
3898 DBG("SIGINT catched");
3899 stop_threads();
3900 break;
3901 case SIGTERM:
3902 DBG("SIGTERM catched");
3903 stop_threads();
3904 break;
3905 default:
3906 break;
3907 }
3908 }
3909
3910 /*
3911 * Setup signal handler for :
3912 * SIGINT, SIGTERM, SIGPIPE
3913 */
3914 static int set_signal_handler(void)
3915 {
3916 int ret = 0;
3917 struct sigaction sa;
3918 sigset_t sigset;
3919
3920 if ((ret = sigemptyset(&sigset)) < 0) {
3921 perror("sigemptyset");
3922 return ret;
3923 }
3924
3925 sa.sa_handler = sighandler;
3926 sa.sa_mask = sigset;
3927 sa.sa_flags = 0;
3928 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
3929 perror("sigaction");
3930 return ret;
3931 }
3932
3933 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
3934 perror("sigaction");
3935 return ret;
3936 }
3937
3938 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
3939 perror("sigaction");
3940 return ret;
3941 }
3942
3943 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3944
3945 return ret;
3946 }
3947
3948 /*
3949 * Set open files limit to unlimited. This daemon can open a large number of
3950 * file descriptors in order to consumer multiple kernel traces.
3951 */
3952 static void set_ulimit(void)
3953 {
3954 int ret;
3955 struct rlimit lim;
3956
3957 /* The kernel does not allowed an infinite limit for open files */
3958 lim.rlim_cur = 65535;
3959 lim.rlim_max = 65535;
3960
3961 ret = setrlimit(RLIMIT_NOFILE, &lim);
3962 if (ret < 0) {
3963 perror("failed to set open files limit");
3964 }
3965 }
3966
3967 /*
3968 * main
3969 */
3970 int main(int argc, char **argv)
3971 {
3972 int ret = 0;
3973 void *status;
3974 const char *home_path;
3975
3976 rcu_register_thread();
3977
3978 /* Create thread quit pipe */
3979 if ((ret = init_thread_quit_pipe()) < 0) {
3980 goto error;
3981 }
3982
3983 setup_consumerd_path();
3984
3985 /* Parse arguments */
3986 progname = argv[0];
3987 if ((ret = parse_args(argc, argv) < 0)) {
3988 goto error;
3989 }
3990
3991 /* Daemonize */
3992 if (opt_daemon) {
3993 ret = daemon(0, 0);
3994 if (ret < 0) {
3995 perror("daemon");
3996 goto error;
3997 }
3998 }
3999
4000 /* Check if daemon is UID = 0 */
4001 is_root = !getuid();
4002
4003 if (is_root) {
4004 ret = create_lttng_rundir();
4005 if (ret < 0) {
4006 goto error;
4007 }
4008
4009 if (strlen(apps_unix_sock_path) == 0) {
4010 snprintf(apps_unix_sock_path, PATH_MAX,
4011 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
4012 }
4013
4014 if (strlen(client_unix_sock_path) == 0) {
4015 snprintf(client_unix_sock_path, PATH_MAX,
4016 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
4017 }
4018
4019 /* Set global SHM for ust */
4020 if (strlen(wait_shm_path) == 0) {
4021 snprintf(wait_shm_path, PATH_MAX,
4022 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
4023 }
4024 } else {
4025 home_path = get_home_dir();
4026 if (home_path == NULL) {
4027 /* TODO: Add --socket PATH option */
4028 ERR("Can't get HOME directory for sockets creation.");
4029 ret = -EPERM;
4030 goto error;
4031 }
4032
4033 if (strlen(apps_unix_sock_path) == 0) {
4034 snprintf(apps_unix_sock_path, PATH_MAX,
4035 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
4036 }
4037
4038 /* Set the cli tool unix socket path */
4039 if (strlen(client_unix_sock_path) == 0) {
4040 snprintf(client_unix_sock_path, PATH_MAX,
4041 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
4042 }
4043
4044 /* Set global SHM for ust */
4045 if (strlen(wait_shm_path) == 0) {
4046 snprintf(wait_shm_path, PATH_MAX,
4047 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
4048 }
4049 }
4050
4051 DBG("Client socket path %s", client_unix_sock_path);
4052 DBG("Application socket path %s", apps_unix_sock_path);
4053
4054 /*
4055 * See if daemon already exist.
4056 */
4057 if ((ret = check_existing_daemon()) < 0) {
4058 ERR("Already running daemon.\n");
4059 /*
4060 * We do not goto exit because we must not cleanup()
4061 * because a daemon is already running.
4062 */
4063 goto error;
4064 }
4065
4066 /* After this point, we can safely call cleanup() with "goto exit" */
4067
4068 /*
4069 * These actions must be executed as root. We do that *after* setting up
4070 * the sockets path because we MUST make the check for another daemon using
4071 * those paths *before* trying to set the kernel consumer sockets and init
4072 * kernel tracer.
4073 */
4074 if (is_root) {
4075 ret = set_consumer_sockets(&kconsumer_data);
4076 if (ret < 0) {
4077 goto exit;
4078 }
4079
4080 ret = set_consumer_sockets(&ustconsumer64_data);
4081 if (ret < 0) {
4082 goto exit;
4083 }
4084
4085 ret = set_consumer_sockets(&ustconsumer32_data);
4086 if (ret < 0) {
4087 goto exit;
4088 }
4089
4090 /* Setup kernel tracer */
4091 init_kernel_tracer();
4092
4093 /* Set ulimit for open files */
4094 set_ulimit();
4095 }
4096
4097 if ((ret = set_signal_handler()) < 0) {
4098 goto exit;
4099 }
4100
4101 /* Setup the needed unix socket */
4102 if ((ret = init_daemon_socket()) < 0) {
4103 goto exit;
4104 }
4105
4106 /* Set credentials to socket */
4107 if (is_root && ((ret = set_permissions()) < 0)) {
4108 goto exit;
4109 }
4110
4111 /* Get parent pid if -S, --sig-parent is specified. */
4112 if (opt_sig_parent) {
4113 ppid = getppid();
4114 }
4115
4116 /* Setup the kernel pipe for waking up the kernel thread */
4117 if ((ret = create_kernel_poll_pipe()) < 0) {
4118 goto exit;
4119 }
4120
4121 /* Setup the thread apps communication pipe. */
4122 if ((ret = create_apps_cmd_pipe()) < 0) {
4123 goto exit;
4124 }
4125
4126 /* Init UST command queue. */
4127 cds_wfq_init(&ust_cmd_queue.queue);
4128
4129 /* Init UST app hash table */
4130 ust_app_ht_alloc();
4131
4132 /*
4133 * Get session list pointer. This pointer MUST NOT be free(). This list is
4134 * statically declared in session.c
4135 */
4136 session_list_ptr = session_get_list();
4137
4138 /* Set up max poll set size */
4139 lttng_poll_set_max_size();
4140
4141 /* Create thread to manage the client socket */
4142 ret = pthread_create(&client_thread, NULL,
4143 thread_manage_clients, (void *) NULL);
4144 if (ret != 0) {
4145 perror("pthread_create clients");
4146 goto exit_client;
4147 }
4148
4149 /* Create thread to dispatch registration */
4150 ret = pthread_create(&dispatch_thread, NULL,
4151 thread_dispatch_ust_registration, (void *) NULL);
4152 if (ret != 0) {
4153 perror("pthread_create dispatch");
4154 goto exit_dispatch;
4155 }
4156
4157 /* Create thread to manage application registration. */
4158 ret = pthread_create(&reg_apps_thread, NULL,
4159 thread_registration_apps, (void *) NULL);
4160 if (ret != 0) {
4161 perror("pthread_create registration");
4162 goto exit_reg_apps;
4163 }
4164
4165 /* Create thread to manage application socket */
4166 ret = pthread_create(&apps_thread, NULL,
4167 thread_manage_apps, (void *) NULL);
4168 if (ret != 0) {
4169 perror("pthread_create apps");
4170 goto exit_apps;
4171 }
4172
4173 /* Create kernel thread to manage kernel event */
4174 ret = pthread_create(&kernel_thread, NULL,
4175 thread_manage_kernel, (void *) NULL);
4176 if (ret != 0) {
4177 perror("pthread_create kernel");
4178 goto exit_kernel;
4179 }
4180
4181 ret = pthread_join(kernel_thread, &status);
4182 if (ret != 0) {
4183 perror("pthread_join");
4184 goto error; /* join error, exit without cleanup */
4185 }
4186
4187 exit_kernel:
4188 ret = pthread_join(apps_thread, &status);
4189 if (ret != 0) {
4190 perror("pthread_join");
4191 goto error; /* join error, exit without cleanup */
4192 }
4193
4194 exit_apps:
4195 ret = pthread_join(reg_apps_thread, &status);
4196 if (ret != 0) {
4197 perror("pthread_join");
4198 goto error; /* join error, exit without cleanup */
4199 }
4200
4201 exit_reg_apps:
4202 ret = pthread_join(dispatch_thread, &status);
4203 if (ret != 0) {
4204 perror("pthread_join");
4205 goto error; /* join error, exit without cleanup */
4206 }
4207
4208 exit_dispatch:
4209 ret = pthread_join(client_thread, &status);
4210 if (ret != 0) {
4211 perror("pthread_join");
4212 goto error; /* join error, exit without cleanup */
4213 }
4214
4215 ret = join_consumer_thread(&kconsumer_data);
4216 if (ret != 0) {
4217 perror("join_consumer");
4218 goto error; /* join error, exit without cleanup */
4219 }
4220
4221 exit_client:
4222 exit:
4223 /*
4224 * cleanup() is called when no other thread is running.
4225 */
4226 rcu_thread_online();
4227 cleanup();
4228 rcu_thread_offline();
4229 rcu_unregister_thread();
4230 if (!ret)
4231 exit(EXIT_SUCCESS);
4232 error:
4233 exit(EXIT_FAILURE);
4234 }
LTTng 2.0 tools and control repository
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