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Fix bad return value on enable syscalls making it freeze
[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.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 #define CONSUMERD_FILE "lttng-consumerd"
61
62 struct consumer_data {
63 enum lttng_consumer_type type;
64
65 pthread_t thread; /* Worker thread interacting with the consumer */
66 sem_t sem;
67
68 /* Mutex to control consumerd pid assignation */
69 pthread_mutex_t pid_mutex;
70 pid_t pid;
71
72 int err_sock;
73 int cmd_sock;
74
75 /* consumer error and command Unix socket path */
76 char err_unix_sock_path[PATH_MAX];
77 char cmd_unix_sock_path[PATH_MAX];
78 };
79
80 /* Const values */
81 const char default_home_dir[] = DEFAULT_HOME_DIR;
82 const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
83 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
84 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
85
86 /* Variables */
87 int opt_verbose; /* Not static for lttngerr.h */
88 int opt_verbose_consumer; /* Not static for lttngerr.h */
89 int opt_quiet; /* Not static for lttngerr.h */
90
91 const char *progname;
92 const char *opt_tracing_group;
93 static int opt_sig_parent;
94 static int opt_daemon;
95 static int is_root; /* Set to 1 if the daemon is running as root */
96 static pid_t ppid; /* Parent PID for --sig-parent option */
97
98 /* Consumer daemon specific control data */
99 static struct consumer_data kconsumer_data = {
100 .type = LTTNG_CONSUMER_KERNEL,
101 .err_unix_sock_path = KCONSUMERD_ERR_SOCK_PATH,
102 .cmd_unix_sock_path = KCONSUMERD_CMD_SOCK_PATH,
103 };
104 static struct consumer_data ustconsumer64_data = {
105 .type = LTTNG_CONSUMER64_UST,
106 .err_unix_sock_path = USTCONSUMERD64_ERR_SOCK_PATH,
107 .cmd_unix_sock_path = USTCONSUMERD64_CMD_SOCK_PATH,
108 };
109 static struct consumer_data ustconsumer32_data = {
110 .type = LTTNG_CONSUMER32_UST,
111 .err_unix_sock_path = USTCONSUMERD32_ERR_SOCK_PATH,
112 .cmd_unix_sock_path = USTCONSUMERD32_CMD_SOCK_PATH,
113 };
114
115 static int dispatch_thread_exit;
116
117 /* Global application Unix socket path */
118 static char apps_unix_sock_path[PATH_MAX];
119 /* Global client Unix socket path */
120 static char client_unix_sock_path[PATH_MAX];
121 /* global wait shm path for UST */
122 static char wait_shm_path[PATH_MAX];
123
124 /* Sockets and FDs */
125 static int client_sock;
126 static int apps_sock;
127 static int kernel_tracer_fd;
128 static int kernel_poll_pipe[2];
129
130 /*
131 * Quit pipe for all threads. This permits a single cancellation point
132 * for all threads when receiving an event on the pipe.
133 */
134 static int thread_quit_pipe[2];
135
136 /*
137 * This pipe is used to inform the thread managing application communication
138 * that a command is queued and ready to be processed.
139 */
140 static int apps_cmd_pipe[2];
141
142 /* Pthread, Mutexes and Semaphores */
143 static pthread_t apps_thread;
144 static pthread_t reg_apps_thread;
145 static pthread_t client_thread;
146 static pthread_t kernel_thread;
147 static pthread_t dispatch_thread;
148
149
150 /*
151 * UST registration command queue. This queue is tied with a futex and uses a N
152 * wakers / 1 waiter implemented and detailed in futex.c/.h
153 *
154 * The thread_manage_apps and thread_dispatch_ust_registration interact with
155 * this queue and the wait/wake scheme.
156 */
157 static struct ust_cmd_queue ust_cmd_queue;
158
159 /*
160 * Pointer initialized before thread creation.
161 *
162 * This points to the tracing session list containing the session count and a
163 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
164 * MUST NOT be taken if you call a public function in session.c.
165 *
166 * The lock is nested inside the structure: session_list_ptr->lock. Please use
167 * session_lock_list and session_unlock_list for lock acquisition.
168 */
169 static struct ltt_session_list *session_list_ptr;
170
171 int ust_consumerd64_fd = -1;
172 int ust_consumerd32_fd = -1;
173
174 static const char *consumerd32_path =
175 __stringify(CONFIG_CONSUMERD32_PATH);
176 static const char *consumerd64_path =
177 __stringify(CONFIG_CONSUMERD64_PATH);
178 static const char *consumerd32_libdir =
179 __stringify(CONFIG_CONSUMERD32_LIBDIR);
180 static const char *consumerd64_libdir =
181 __stringify(CONFIG_CONSUMERD64_LIBDIR);
182
183 static
184 void setup_consumerd_path(void)
185 {
186 const char *path, *libdir;
187
188 /*
189 * Allow INSTALL_BIN_PATH to be used as a target path for the
190 * native architecture size consumer if CONFIG_CONSUMER*_PATH
191 * has not been defined.
192 */
193 #if (CAA_BITS_PER_LONG == 32)
194 if (!consumerd32_path[0]) {
195 consumerd32_path = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
196 }
197 if (!consumerd32_libdir[0]) {
198 consumerd32_libdir = INSTALL_LIB_PATH;
199 }
200 #elif (CAA_BITS_PER_LONG == 64)
201 if (!consumerd64_path[0]) {
202 consumerd64_path = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
203 }
204 if (!consumerd64_libdir[0]) {
205 consumerd64_libdir = INSTALL_LIB_PATH;
206 }
207 #else
208 #error "Unknown bitness"
209 #endif
210
211 /*
212 * runtime env. var. overrides the build default.
213 */
214 path = getenv("LTTNG_CONSUMERD32_PATH");
215 if (path) {
216 consumerd32_path = path;
217 }
218 path = getenv("LTTNG_CONSUMERD64_PATH");
219 if (path) {
220 consumerd64_path = path;
221 }
222 libdir = getenv("LTTNG_TOOLS_CONSUMERD32_LIBDIR");
223 if (libdir) {
224 consumerd32_libdir = libdir;
225 }
226 libdir = getenv("LTTNG_TOOLS_CONSUMERD64_LIBDIR");
227 if (libdir) {
228 consumerd64_libdir = libdir;
229 }
230 }
231
232 /*
233 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
234 */
235 static int create_thread_poll_set(struct lttng_poll_event *events,
236 unsigned int size)
237 {
238 int ret;
239
240 if (events == NULL || size == 0) {
241 ret = -1;
242 goto error;
243 }
244
245 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
246 if (ret < 0) {
247 goto error;
248 }
249
250 /* Add quit pipe */
251 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
252 if (ret < 0) {
253 goto error;
254 }
255
256 return 0;
257
258 error:
259 return ret;
260 }
261
262 /*
263 * Check if the thread quit pipe was triggered.
264 *
265 * Return 1 if it was triggered else 0;
266 */
267 static int check_thread_quit_pipe(int fd, uint32_t events)
268 {
269 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
270 return 1;
271 }
272
273 return 0;
274 }
275
276 /*
277 * Remove modules in reverse load order.
278 */
279 static int modprobe_remove_kernel_modules(void)
280 {
281 int ret = 0, i;
282 char modprobe[256];
283
284 for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
285 ret = snprintf(modprobe, sizeof(modprobe),
286 "/sbin/modprobe -r -q %s",
287 kernel_modules_list[i].name);
288 if (ret < 0) {
289 perror("snprintf modprobe -r");
290 goto error;
291 }
292 modprobe[sizeof(modprobe) - 1] = '\0';
293 ret = system(modprobe);
294 if (ret == -1) {
295 ERR("Unable to launch modprobe -r for module %s",
296 kernel_modules_list[i].name);
297 } else if (kernel_modules_list[i].required
298 && WEXITSTATUS(ret) != 0) {
299 ERR("Unable to remove module %s",
300 kernel_modules_list[i].name);
301 } else {
302 DBG("Modprobe removal successful %s",
303 kernel_modules_list[i].name);
304 }
305 }
306
307 error:
308 return ret;
309 }
310
311 /*
312 * Return group ID of the tracing group or -1 if not found.
313 */
314 static gid_t allowed_group(void)
315 {
316 struct group *grp;
317
318 if (opt_tracing_group) {
319 grp = getgrnam(opt_tracing_group);
320 } else {
321 grp = getgrnam(default_tracing_group);
322 }
323 if (!grp) {
324 return -1;
325 } else {
326 return grp->gr_gid;
327 }
328 }
329
330 /*
331 * Init thread quit pipe.
332 *
333 * Return -1 on error or 0 if all pipes are created.
334 */
335 static int init_thread_quit_pipe(void)
336 {
337 int ret;
338
339 ret = pipe2(thread_quit_pipe, O_CLOEXEC);
340 if (ret < 0) {
341 perror("thread quit pipe");
342 goto error;
343 }
344
345 error:
346 return ret;
347 }
348
349 /*
350 * Complete teardown of a kernel session. This free all data structure related
351 * to a kernel session and update counter.
352 */
353 static void teardown_kernel_session(struct ltt_session *session)
354 {
355 if (!session->kernel_session) {
356 DBG3("No kernel session when tearingdown session");
357 return;
358 }
359
360 DBG("Tearing down kernel session");
361
362 /*
363 * If a custom kernel consumer was registered, close the socket before
364 * tearing down the complete kernel session structure
365 */
366 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
367 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
368 }
369
370 trace_kernel_destroy_session(session->kernel_session);
371 }
372
373 /*
374 * Complete teardown of all UST sessions. This will free everything on his path
375 * and destroy the core essence of all ust sessions :)
376 */
377 static void teardown_ust_session(struct ltt_session *session)
378 {
379 int ret;
380
381 if (!session->ust_session) {
382 DBG3("No UST session when tearingdown session");
383 return;
384 }
385
386 DBG("Tearing down UST session(s)");
387
388 ret = ust_app_destroy_trace_all(session->ust_session);
389 if (ret) {
390 ERR("Error in ust_app_destroy_trace_all");
391 }
392
393 trace_ust_destroy_session(session->ust_session);
394 }
395
396 /*
397 * Stop all threads by closing the thread quit pipe.
398 */
399 static void stop_threads(void)
400 {
401 int ret;
402
403 /* Stopping all threads */
404 DBG("Terminating all threads");
405 ret = notify_thread_pipe(thread_quit_pipe[1]);
406 if (ret < 0) {
407 ERR("write error on thread quit pipe");
408 }
409
410 /* Dispatch thread */
411 dispatch_thread_exit = 1;
412 futex_nto1_wake(&ust_cmd_queue.futex);
413 }
414
415 /*
416 * Cleanup the daemon
417 */
418 static void cleanup(void)
419 {
420 int ret;
421 char *cmd;
422 struct ltt_session *sess, *stmp;
423
424 DBG("Cleaning up");
425
426 if (is_root) {
427 DBG("Removing %s directory", LTTNG_RUNDIR);
428 ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
429 if (ret < 0) {
430 ERR("asprintf failed. Something is really wrong!");
431 }
432
433 /* Remove lttng run directory */
434 ret = system(cmd);
435 if (ret < 0) {
436 ERR("Unable to clean " LTTNG_RUNDIR);
437 }
438 }
439
440 DBG("Cleaning up all session");
441
442 /* Destroy session list mutex */
443 if (session_list_ptr != NULL) {
444 pthread_mutex_destroy(&session_list_ptr->lock);
445
446 /* Cleanup ALL session */
447 cds_list_for_each_entry_safe(sess, stmp,
448 &session_list_ptr->head, list) {
449 teardown_kernel_session(sess);
450 teardown_ust_session(sess);
451 free(sess);
452 }
453 }
454
455 DBG("Closing all UST sockets");
456 ust_app_clean_list();
457
458 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
459
460 DBG("Closing kernel fd");
461 close(kernel_tracer_fd);
462
463 if (is_root) {
464 DBG("Unloading kernel modules");
465 modprobe_remove_kernel_modules();
466 }
467
468 close(thread_quit_pipe[0]);
469 close(thread_quit_pipe[1]);
470
471 /* <fun> */
472 MSG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
473 "Matthew, BEET driven development works!%c[%dm",
474 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
475 /* </fun> */
476 }
477
478 /*
479 * Send data on a unix socket using the liblttsessiondcomm API.
480 *
481 * Return lttcomm error code.
482 */
483 static int send_unix_sock(int sock, void *buf, size_t len)
484 {
485 /* Check valid length */
486 if (len <= 0) {
487 return -1;
488 }
489
490 return lttcomm_send_unix_sock(sock, buf, len);
491 }
492
493 /*
494 * Free memory of a command context structure.
495 */
496 static void clean_command_ctx(struct command_ctx **cmd_ctx)
497 {
498 DBG("Clean command context structure");
499 if (*cmd_ctx) {
500 if ((*cmd_ctx)->llm) {
501 free((*cmd_ctx)->llm);
502 }
503 if ((*cmd_ctx)->lsm) {
504 free((*cmd_ctx)->lsm);
505 }
506 free(*cmd_ctx);
507 *cmd_ctx = NULL;
508 }
509 }
510
511 /*
512 * Send all stream fds of kernel channel to the consumer.
513 */
514 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
515 int sock, struct ltt_kernel_channel *channel)
516 {
517 int ret;
518 struct ltt_kernel_stream *stream;
519 struct lttcomm_consumer_msg lkm;
520
521 DBG("Sending streams of channel %s to kernel consumer",
522 channel->channel->name);
523
524 /* Send channel */
525 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
526 lkm.u.channel.channel_key = channel->fd;
527 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
528 lkm.u.channel.mmap_len = 0; /* for kernel */
529 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
530 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
531 if (ret < 0) {
532 perror("send consumer channel");
533 goto error;
534 }
535
536 /* Send streams */
537 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
538 if (!stream->fd) {
539 continue;
540 }
541 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
542 lkm.u.stream.channel_key = channel->fd;
543 lkm.u.stream.stream_key = stream->fd;
544 lkm.u.stream.state = stream->state;
545 lkm.u.stream.output = channel->channel->attr.output;
546 lkm.u.stream.mmap_len = 0; /* for kernel */
547 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
548 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
549 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
550 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
551 if (ret < 0) {
552 perror("send consumer stream");
553 goto error;
554 }
555 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
556 if (ret < 0) {
557 perror("send consumer stream ancillary data");
558 goto error;
559 }
560 }
561
562 DBG("consumer channel streams sent");
563
564 return 0;
565
566 error:
567 return ret;
568 }
569
570 /*
571 * Send all stream fds of the kernel session to the consumer.
572 */
573 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
574 struct ltt_kernel_session *session)
575 {
576 int ret;
577 struct ltt_kernel_channel *chan;
578 struct lttcomm_consumer_msg lkm;
579 int sock = session->consumer_fd;
580
581 DBG("Sending metadata stream fd");
582
583 /* Extra protection. It's NOT supposed to be set to 0 at this point */
584 if (session->consumer_fd == 0) {
585 session->consumer_fd = consumer_data->cmd_sock;
586 }
587
588 if (session->metadata_stream_fd != 0) {
589 /* Send metadata channel fd */
590 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
591 lkm.u.channel.channel_key = session->metadata->fd;
592 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
593 lkm.u.channel.mmap_len = 0; /* for kernel */
594 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
595 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
596 if (ret < 0) {
597 perror("send consumer channel");
598 goto error;
599 }
600
601 /* Send metadata stream fd */
602 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
603 lkm.u.stream.channel_key = session->metadata->fd;
604 lkm.u.stream.stream_key = session->metadata_stream_fd;
605 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
606 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
607 lkm.u.stream.mmap_len = 0; /* for kernel */
608 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
609 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
610 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
611 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
612 if (ret < 0) {
613 perror("send consumer stream");
614 goto error;
615 }
616 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
617 if (ret < 0) {
618 perror("send consumer stream");
619 goto error;
620 }
621 }
622
623 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
624 ret = send_kconsumer_channel_streams(consumer_data, sock, chan);
625 if (ret < 0) {
626 goto error;
627 }
628 }
629
630 DBG("consumer fds (metadata and channel streams) sent");
631
632 return 0;
633
634 error:
635 return ret;
636 }
637
638 /*
639 * Notify UST applications using the shm mmap futex.
640 */
641 static int notify_ust_apps(int active)
642 {
643 char *wait_shm_mmap;
644
645 DBG("Notifying applications of session daemon state: %d", active);
646
647 /* See shm.c for this call implying mmap, shm and futex calls */
648 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
649 if (wait_shm_mmap == NULL) {
650 goto error;
651 }
652
653 /* Wake waiting process */
654 futex_wait_update((int32_t *) wait_shm_mmap, active);
655
656 /* Apps notified successfully */
657 return 0;
658
659 error:
660 return -1;
661 }
662
663 /*
664 * Setup the outgoing data buffer for the response (llm) by allocating the
665 * right amount of memory and copying the original information from the lsm
666 * structure.
667 *
668 * Return total size of the buffer pointed by buf.
669 */
670 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
671 {
672 int ret, buf_size;
673
674 buf_size = size;
675
676 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
677 if (cmd_ctx->llm == NULL) {
678 perror("zmalloc");
679 ret = -ENOMEM;
680 goto error;
681 }
682
683 /* Copy common data */
684 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
685 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
686
687 cmd_ctx->llm->data_size = size;
688 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
689
690 return buf_size;
691
692 error:
693 return ret;
694 }
695
696 /*
697 * Update the kernel poll set of all channel fd available over all tracing
698 * session. Add the wakeup pipe at the end of the set.
699 */
700 static int update_kernel_poll(struct lttng_poll_event *events)
701 {
702 int ret;
703 struct ltt_session *session;
704 struct ltt_kernel_channel *channel;
705
706 DBG("Updating kernel poll set");
707
708 session_lock_list();
709 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
710 session_lock(session);
711 if (session->kernel_session == NULL) {
712 session_unlock(session);
713 continue;
714 }
715
716 cds_list_for_each_entry(channel,
717 &session->kernel_session->channel_list.head, list) {
718 /* Add channel fd to the kernel poll set */
719 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
720 if (ret < 0) {
721 session_unlock(session);
722 goto error;
723 }
724 DBG("Channel fd %d added to kernel set", channel->fd);
725 }
726 session_unlock(session);
727 }
728 session_unlock_list();
729
730 return 0;
731
732 error:
733 session_unlock_list();
734 return -1;
735 }
736
737 /*
738 * Find the channel fd from 'fd' over all tracing session. When found, check
739 * for new channel stream and send those stream fds to the kernel consumer.
740 *
741 * Useful for CPU hotplug feature.
742 */
743 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
744 {
745 int ret = 0;
746 struct ltt_session *session;
747 struct ltt_kernel_channel *channel;
748
749 DBG("Updating kernel streams for channel fd %d", fd);
750
751 session_lock_list();
752 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
753 session_lock(session);
754 if (session->kernel_session == NULL) {
755 session_unlock(session);
756 continue;
757 }
758
759 /* This is not suppose to be 0 but this is an extra security check */
760 if (session->kernel_session->consumer_fd == 0) {
761 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
762 }
763
764 cds_list_for_each_entry(channel,
765 &session->kernel_session->channel_list.head, list) {
766 if (channel->fd == fd) {
767 DBG("Channel found, updating kernel streams");
768 ret = kernel_open_channel_stream(channel);
769 if (ret < 0) {
770 goto error;
771 }
772
773 /*
774 * Have we already sent fds to the consumer? If yes, it means
775 * that tracing is started so it is safe to send our updated
776 * stream fds.
777 */
778 if (session->kernel_session->consumer_fds_sent == 1) {
779 ret = send_kconsumer_channel_streams(consumer_data,
780 session->kernel_session->consumer_fd, channel);
781 if (ret < 0) {
782 goto error;
783 }
784 }
785 goto error;
786 }
787 }
788 session_unlock(session);
789 }
790 session_unlock_list();
791 return ret;
792
793 error:
794 session_unlock(session);
795 session_unlock_list();
796 return ret;
797 }
798
799 /*
800 * For each tracing session, update newly registered apps.
801 */
802 static void update_ust_app(int app_sock)
803 {
804 struct ltt_session *sess, *stmp;
805
806 /* For all tracing session(s) */
807 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
808 if (sess->ust_session) {
809 ust_app_global_update(sess->ust_session, app_sock);
810 }
811 }
812 }
813
814 /*
815 * This thread manage event coming from the kernel.
816 *
817 * Features supported in this thread:
818 * -) CPU Hotplug
819 */
820 static void *thread_manage_kernel(void *data)
821 {
822 int ret, i, pollfd, update_poll_flag = 1;
823 uint32_t revents, nb_fd;
824 char tmp;
825 struct lttng_poll_event events;
826
827 DBG("Thread manage kernel started");
828
829 ret = create_thread_poll_set(&events, 2);
830 if (ret < 0) {
831 goto error;
832 }
833
834 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
835 if (ret < 0) {
836 goto error;
837 }
838
839 while (1) {
840 if (update_poll_flag == 1) {
841 /*
842 * Reset number of fd in the poll set. Always 2 since there is the thread
843 * quit pipe and the kernel pipe.
844 */
845 events.nb_fd = 2;
846
847 ret = update_kernel_poll(&events);
848 if (ret < 0) {
849 goto error;
850 }
851 update_poll_flag = 0;
852 }
853
854 nb_fd = LTTNG_POLL_GETNB(&events);
855
856 DBG("Thread kernel polling on %d fds", nb_fd);
857
858 /* Zeroed the poll events */
859 lttng_poll_reset(&events);
860
861 /* Poll infinite value of time */
862 ret = lttng_poll_wait(&events, -1);
863 if (ret < 0) {
864 goto error;
865 } else if (ret == 0) {
866 /* Should not happen since timeout is infinite */
867 ERR("Return value of poll is 0 with an infinite timeout.\n"
868 "This should not have happened! Continuing...");
869 continue;
870 }
871
872 for (i = 0; i < nb_fd; i++) {
873 /* Fetch once the poll data */
874 revents = LTTNG_POLL_GETEV(&events, i);
875 pollfd = LTTNG_POLL_GETFD(&events, i);
876
877 /* Thread quit pipe has been closed. Killing thread. */
878 ret = check_thread_quit_pipe(pollfd, revents);
879 if (ret) {
880 goto error;
881 }
882
883 /* Check for data on kernel pipe */
884 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
885 ret = read(kernel_poll_pipe[0], &tmp, 1);
886 update_poll_flag = 1;
887 continue;
888 } else {
889 /*
890 * New CPU detected by the kernel. Adding kernel stream to
891 * kernel session and updating the kernel consumer
892 */
893 if (revents & LPOLLIN) {
894 ret = update_kernel_stream(&kconsumer_data, pollfd);
895 if (ret < 0) {
896 continue;
897 }
898 break;
899 /*
900 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
901 * and unregister kernel stream at this point.
902 */
903 }
904 }
905 }
906 }
907
908 error:
909 DBG("Kernel thread dying");
910 close(kernel_poll_pipe[0]);
911 close(kernel_poll_pipe[1]);
912
913 lttng_poll_clean(&events);
914
915 return NULL;
916 }
917
918 /*
919 * This thread manage the consumer error sent back to the session daemon.
920 */
921 static void *thread_manage_consumer(void *data)
922 {
923 int sock = 0, i, ret, pollfd;
924 uint32_t revents, nb_fd;
925 enum lttcomm_return_code code;
926 struct lttng_poll_event events;
927 struct consumer_data *consumer_data = data;
928
929 DBG("[thread] Manage consumer started");
930
931 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
932 if (ret < 0) {
933 goto error;
934 }
935
936 /*
937 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
938 * Nothing more will be added to this poll set.
939 */
940 ret = create_thread_poll_set(&events, 2);
941 if (ret < 0) {
942 goto error;
943 }
944
945 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
946 if (ret < 0) {
947 goto error;
948 }
949
950 nb_fd = LTTNG_POLL_GETNB(&events);
951
952 /* Inifinite blocking call, waiting for transmission */
953 ret = lttng_poll_wait(&events, -1);
954 if (ret < 0) {
955 goto error;
956 }
957
958 for (i = 0; i < nb_fd; i++) {
959 /* Fetch once the poll data */
960 revents = LTTNG_POLL_GETEV(&events, i);
961 pollfd = LTTNG_POLL_GETFD(&events, i);
962
963 /* Thread quit pipe has been closed. Killing thread. */
964 ret = check_thread_quit_pipe(pollfd, revents);
965 if (ret) {
966 goto error;
967 }
968
969 /* Event on the registration socket */
970 if (pollfd == consumer_data->err_sock) {
971 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
972 ERR("consumer err socket poll error");
973 goto error;
974 }
975 }
976 }
977
978 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
979 if (sock < 0) {
980 goto error;
981 }
982
983 DBG2("Receiving code from consumer err_sock");
984
985 /* Getting status code from kconsumerd */
986 ret = lttcomm_recv_unix_sock(sock, &code,
987 sizeof(enum lttcomm_return_code));
988 if (ret <= 0) {
989 goto error;
990 }
991
992 if (code == CONSUMERD_COMMAND_SOCK_READY) {
993 consumer_data->cmd_sock =
994 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
995 if (consumer_data->cmd_sock < 0) {
996 sem_post(&consumer_data->sem);
997 PERROR("consumer connect");
998 goto error;
999 }
1000 /* Signal condition to tell that the kconsumerd is ready */
1001 sem_post(&consumer_data->sem);
1002 DBG("consumer command socket ready");
1003 } else {
1004 ERR("consumer error when waiting for SOCK_READY : %s",
1005 lttcomm_get_readable_code(-code));
1006 goto error;
1007 }
1008
1009 /* Remove the kconsumerd error sock since we've established a connexion */
1010 ret = lttng_poll_del(&events, consumer_data->err_sock);
1011 if (ret < 0) {
1012 goto error;
1013 }
1014
1015 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1016 if (ret < 0) {
1017 goto error;
1018 }
1019
1020 /* Update number of fd */
1021 nb_fd = LTTNG_POLL_GETNB(&events);
1022
1023 /* Inifinite blocking call, waiting for transmission */
1024 ret = lttng_poll_wait(&events, -1);
1025 if (ret < 0) {
1026 goto error;
1027 }
1028
1029 for (i = 0; i < nb_fd; i++) {
1030 /* Fetch once the poll data */
1031 revents = LTTNG_POLL_GETEV(&events, i);
1032 pollfd = LTTNG_POLL_GETFD(&events, i);
1033
1034 /* Thread quit pipe has been closed. Killing thread. */
1035 ret = check_thread_quit_pipe(pollfd, revents);
1036 if (ret) {
1037 goto error;
1038 }
1039
1040 /* Event on the kconsumerd socket */
1041 if (pollfd == sock) {
1042 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1043 ERR("consumer err socket second poll error");
1044 goto error;
1045 }
1046 }
1047 }
1048
1049 /* Wait for any kconsumerd error */
1050 ret = lttcomm_recv_unix_sock(sock, &code,
1051 sizeof(enum lttcomm_return_code));
1052 if (ret <= 0) {
1053 ERR("consumer closed the command socket");
1054 goto error;
1055 }
1056
1057 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1058
1059 error:
1060 DBG("consumer thread dying");
1061 close(consumer_data->err_sock);
1062 close(consumer_data->cmd_sock);
1063 close(sock);
1064
1065 unlink(consumer_data->err_unix_sock_path);
1066 unlink(consumer_data->cmd_unix_sock_path);
1067 consumer_data->pid = 0;
1068
1069 lttng_poll_clean(&events);
1070
1071 return NULL;
1072 }
1073
1074 /*
1075 * This thread manage application communication.
1076 */
1077 static void *thread_manage_apps(void *data)
1078 {
1079 int i, ret, pollfd;
1080 uint32_t revents, nb_fd;
1081 struct ust_command ust_cmd;
1082 struct lttng_poll_event events;
1083
1084 DBG("[thread] Manage application started");
1085
1086 rcu_register_thread();
1087 rcu_thread_online();
1088
1089 ret = create_thread_poll_set(&events, 2);
1090 if (ret < 0) {
1091 goto error;
1092 }
1093
1094 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1095 if (ret < 0) {
1096 goto error;
1097 }
1098
1099 while (1) {
1100 /* Zeroed the events structure */
1101 lttng_poll_reset(&events);
1102
1103 nb_fd = LTTNG_POLL_GETNB(&events);
1104
1105 DBG("Apps thread polling on %d fds", nb_fd);
1106
1107 /* Inifinite blocking call, waiting for transmission */
1108 ret = lttng_poll_wait(&events, -1);
1109 if (ret < 0) {
1110 goto error;
1111 }
1112
1113 for (i = 0; i < nb_fd; i++) {
1114 /* Fetch once the poll data */
1115 revents = LTTNG_POLL_GETEV(&events, i);
1116 pollfd = LTTNG_POLL_GETFD(&events, i);
1117
1118 /* Thread quit pipe has been closed. Killing thread. */
1119 ret = check_thread_quit_pipe(pollfd, revents);
1120 if (ret) {
1121 goto error;
1122 }
1123
1124 /* Inspect the apps cmd pipe */
1125 if (pollfd == apps_cmd_pipe[0]) {
1126 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1127 ERR("Apps command pipe error");
1128 goto error;
1129 } else if (revents & LPOLLIN) {
1130 /* Empty pipe */
1131 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1132 if (ret < 0 || ret < sizeof(ust_cmd)) {
1133 perror("read apps cmd pipe");
1134 goto error;
1135 }
1136
1137 /* Register applicaton to the session daemon */
1138 ret = ust_app_register(&ust_cmd.reg_msg,
1139 ust_cmd.sock);
1140 if (ret == -ENOMEM) {
1141 goto error;
1142 } else if (ret < 0) {
1143 break;
1144 }
1145
1146 /*
1147 * Add channel(s) and event(s) to newly registered apps
1148 * from lttng global UST domain.
1149 */
1150 update_ust_app(ust_cmd.sock);
1151
1152 ret = ustctl_register_done(ust_cmd.sock);
1153 if (ret < 0) {
1154 /*
1155 * If the registration is not possible, we simply
1156 * unregister the apps and continue
1157 */
1158 ust_app_unregister(ust_cmd.sock);
1159 } else {
1160 /*
1161 * We just need here to monitor the close of the UST
1162 * socket and poll set monitor those by default.
1163 */
1164 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1165 if (ret < 0) {
1166 goto error;
1167 }
1168
1169 DBG("Apps with sock %d added to poll set",
1170 ust_cmd.sock);
1171 }
1172
1173 break;
1174 }
1175 } else {
1176 /*
1177 * At this point, we know that a registered application made
1178 * the event at poll_wait.
1179 */
1180 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1181 /* Removing from the poll set */
1182 ret = lttng_poll_del(&events, pollfd);
1183 if (ret < 0) {
1184 goto error;
1185 }
1186
1187 /* Socket closed on remote end. */
1188 ust_app_unregister(pollfd);
1189 break;
1190 }
1191 }
1192 }
1193 }
1194
1195 error:
1196 DBG("Application communication apps dying");
1197 close(apps_cmd_pipe[0]);
1198 close(apps_cmd_pipe[1]);
1199
1200 lttng_poll_clean(&events);
1201
1202 rcu_thread_offline();
1203 rcu_unregister_thread();
1204 return NULL;
1205 }
1206
1207 /*
1208 * Dispatch request from the registration threads to the application
1209 * communication thread.
1210 */
1211 static void *thread_dispatch_ust_registration(void *data)
1212 {
1213 int ret;
1214 struct cds_wfq_node *node;
1215 struct ust_command *ust_cmd = NULL;
1216
1217 DBG("[thread] Dispatch UST command started");
1218
1219 while (!dispatch_thread_exit) {
1220 /* Atomically prepare the queue futex */
1221 futex_nto1_prepare(&ust_cmd_queue.futex);
1222
1223 do {
1224 /* Dequeue command for registration */
1225 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1226 if (node == NULL) {
1227 DBG("Woken up but nothing in the UST command queue");
1228 /* Continue thread execution */
1229 break;
1230 }
1231
1232 ust_cmd = caa_container_of(node, struct ust_command, node);
1233
1234 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1235 " gid:%d sock:%d name:%s (version %d.%d)",
1236 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1237 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1238 ust_cmd->sock, ust_cmd->reg_msg.name,
1239 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1240 /*
1241 * Inform apps thread of the new application registration. This
1242 * call is blocking so we can be assured that the data will be read
1243 * at some point in time or wait to the end of the world :)
1244 */
1245 ret = write(apps_cmd_pipe[1], ust_cmd,
1246 sizeof(struct ust_command));
1247 if (ret < 0) {
1248 perror("write apps cmd pipe");
1249 if (errno == EBADF) {
1250 /*
1251 * We can't inform the application thread to process
1252 * registration. We will exit or else application
1253 * registration will not occur and tracing will never
1254 * start.
1255 */
1256 goto error;
1257 }
1258 }
1259 free(ust_cmd);
1260 } while (node != NULL);
1261
1262 /* Futex wait on queue. Blocking call on futex() */
1263 futex_nto1_wait(&ust_cmd_queue.futex);
1264 }
1265
1266 error:
1267 DBG("Dispatch thread dying");
1268 return NULL;
1269 }
1270
1271 /*
1272 * This thread manage application registration.
1273 */
1274 static void *thread_registration_apps(void *data)
1275 {
1276 int sock = 0, i, ret, pollfd;
1277 uint32_t revents, nb_fd;
1278 struct lttng_poll_event events;
1279 /*
1280 * Get allocated in this thread, enqueued to a global queue, dequeued and
1281 * freed in the manage apps thread.
1282 */
1283 struct ust_command *ust_cmd = NULL;
1284
1285 DBG("[thread] Manage application registration started");
1286
1287 ret = lttcomm_listen_unix_sock(apps_sock);
1288 if (ret < 0) {
1289 goto error;
1290 }
1291
1292 /*
1293 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1294 * more will be added to this poll set.
1295 */
1296 ret = create_thread_poll_set(&events, 2);
1297 if (ret < 0) {
1298 goto error;
1299 }
1300
1301 /* Add the application registration socket */
1302 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1303 if (ret < 0) {
1304 goto error;
1305 }
1306
1307 /* Notify all applications to register */
1308 ret = notify_ust_apps(1);
1309 if (ret < 0) {
1310 ERR("Failed to notify applications or create the wait shared memory.\n"
1311 "Execution continues but there might be problem for already\n"
1312 "running applications that wishes to register.");
1313 }
1314
1315 while (1) {
1316 DBG("Accepting application registration");
1317
1318 nb_fd = LTTNG_POLL_GETNB(&events);
1319
1320 /* Inifinite blocking call, waiting for transmission */
1321 ret = lttng_poll_wait(&events, -1);
1322 if (ret < 0) {
1323 goto error;
1324 }
1325
1326 for (i = 0; i < nb_fd; i++) {
1327 /* Fetch once the poll data */
1328 revents = LTTNG_POLL_GETEV(&events, i);
1329 pollfd = LTTNG_POLL_GETFD(&events, i);
1330
1331 /* Thread quit pipe has been closed. Killing thread. */
1332 ret = check_thread_quit_pipe(pollfd, revents);
1333 if (ret) {
1334 goto error;
1335 }
1336
1337 /* Event on the registration socket */
1338 if (pollfd == apps_sock) {
1339 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1340 ERR("Register apps socket poll error");
1341 goto error;
1342 } else if (revents & LPOLLIN) {
1343 sock = lttcomm_accept_unix_sock(apps_sock);
1344 if (sock < 0) {
1345 goto error;
1346 }
1347
1348 /* Create UST registration command for enqueuing */
1349 ust_cmd = zmalloc(sizeof(struct ust_command));
1350 if (ust_cmd == NULL) {
1351 perror("ust command zmalloc");
1352 goto error;
1353 }
1354
1355 /*
1356 * Using message-based transmissions to ensure we don't
1357 * have to deal with partially received messages.
1358 */
1359 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1360 sizeof(struct ust_register_msg));
1361 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1362 if (ret < 0) {
1363 perror("lttcomm_recv_unix_sock register apps");
1364 } else {
1365 ERR("Wrong size received on apps register");
1366 }
1367 free(ust_cmd);
1368 close(sock);
1369 continue;
1370 }
1371
1372 ust_cmd->sock = sock;
1373
1374 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1375 " gid:%d sock:%d name:%s (version %d.%d)",
1376 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1377 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1378 ust_cmd->sock, ust_cmd->reg_msg.name,
1379 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1380
1381 /*
1382 * Lock free enqueue the registration request. The red pill
1383 * has been taken! This apps will be part of the *system*.
1384 */
1385 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1386
1387 /*
1388 * Wake the registration queue futex. Implicit memory
1389 * barrier with the exchange in cds_wfq_enqueue.
1390 */
1391 futex_nto1_wake(&ust_cmd_queue.futex);
1392 }
1393 }
1394 }
1395 }
1396
1397 error:
1398 DBG("UST Registration thread dying");
1399
1400 /* Notify that the registration thread is gone */
1401 notify_ust_apps(0);
1402
1403 close(apps_sock);
1404 close(sock);
1405 unlink(apps_unix_sock_path);
1406
1407 lttng_poll_clean(&events);
1408
1409 return NULL;
1410 }
1411
1412 /*
1413 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1414 * exec or it will fails.
1415 */
1416 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1417 {
1418 int ret;
1419 struct timespec timeout;
1420
1421 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1422 timeout.tv_nsec = 0;
1423
1424 /* Setup semaphore */
1425 ret = sem_init(&consumer_data->sem, 0, 0);
1426 if (ret < 0) {
1427 PERROR("sem_init consumer semaphore");
1428 goto error;
1429 }
1430
1431 ret = pthread_create(&consumer_data->thread, NULL,
1432 thread_manage_consumer, consumer_data);
1433 if (ret != 0) {
1434 PERROR("pthread_create consumer");
1435 ret = -1;
1436 goto error;
1437 }
1438
1439 /* Get time for sem_timedwait absolute timeout */
1440 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1441 if (ret < 0) {
1442 PERROR("clock_gettime spawn consumer");
1443 /* Infinite wait for the kconsumerd thread to be ready */
1444 ret = sem_wait(&consumer_data->sem);
1445 } else {
1446 /* Normal timeout if the gettime was successful */
1447 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1448 ret = sem_timedwait(&consumer_data->sem, &timeout);
1449 }
1450
1451 if (ret < 0) {
1452 if (errno == ETIMEDOUT) {
1453 /*
1454 * Call has timed out so we kill the kconsumerd_thread and return
1455 * an error.
1456 */
1457 ERR("The consumer thread was never ready. Killing it");
1458 ret = pthread_cancel(consumer_data->thread);
1459 if (ret < 0) {
1460 PERROR("pthread_cancel consumer thread");
1461 }
1462 } else {
1463 PERROR("semaphore wait failed consumer thread");
1464 }
1465 goto error;
1466 }
1467
1468 pthread_mutex_lock(&consumer_data->pid_mutex);
1469 if (consumer_data->pid == 0) {
1470 ERR("Kconsumerd did not start");
1471 pthread_mutex_unlock(&consumer_data->pid_mutex);
1472 goto error;
1473 }
1474 pthread_mutex_unlock(&consumer_data->pid_mutex);
1475
1476 return 0;
1477
1478 error:
1479 return ret;
1480 }
1481
1482 /*
1483 * Join consumer thread
1484 */
1485 static int join_consumer_thread(struct consumer_data *consumer_data)
1486 {
1487 void *status;
1488 int ret;
1489
1490 if (consumer_data->pid != 0) {
1491 ret = kill(consumer_data->pid, SIGTERM);
1492 if (ret) {
1493 ERR("Error killing consumer daemon");
1494 return ret;
1495 }
1496 return pthread_join(consumer_data->thread, &status);
1497 } else {
1498 return 0;
1499 }
1500 }
1501
1502 /*
1503 * Fork and exec a consumer daemon (consumerd).
1504 *
1505 * Return pid if successful else -1.
1506 */
1507 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1508 {
1509 int ret;
1510 pid_t pid;
1511 const char *verbosity;
1512
1513 DBG("Spawning consumerd");
1514
1515 pid = fork();
1516 if (pid == 0) {
1517 /*
1518 * Exec consumerd.
1519 */
1520 if (opt_verbose > 1 || opt_verbose_consumer) {
1521 verbosity = "--verbose";
1522 } else {
1523 verbosity = "--quiet";
1524 }
1525 switch (consumer_data->type) {
1526 case LTTNG_CONSUMER_KERNEL:
1527 execl(INSTALL_BIN_PATH "/lttng-consumerd",
1528 "lttng-consumerd", verbosity, "-k",
1529 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1530 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1531 NULL);
1532 break;
1533 case LTTNG_CONSUMER64_UST:
1534 {
1535 char *tmpnew = NULL;
1536
1537 if (consumerd64_libdir[0] != '\0') {
1538 char *tmp;
1539 size_t tmplen;
1540
1541 tmp = getenv("LD_LIBRARY_PATH");
1542 if (!tmp) {
1543 tmp = "";
1544 }
1545 tmplen = strlen("LD_LIBRARY_PATH=")
1546 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1547 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1548 if (!tmpnew) {
1549 ret = -ENOMEM;
1550 goto error;
1551 }
1552 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1553 strcat(tmpnew, consumerd64_libdir);
1554 if (tmp[0] != '\0') {
1555 strcat(tmpnew, ":");
1556 strcat(tmpnew, tmp);
1557 }
1558 ret = putenv(tmpnew);
1559 if (ret) {
1560 ret = -errno;
1561 goto error;
1562 }
1563 }
1564 ret = execl(consumerd64_path, verbosity, "-u",
1565 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1566 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1567 NULL);
1568 if (consumerd64_libdir[0] != '\0') {
1569 free(tmpnew);
1570 }
1571 if (ret) {
1572 goto error;
1573 }
1574 break;
1575 }
1576 case LTTNG_CONSUMER32_UST:
1577 {
1578 char *tmpnew = NULL;
1579
1580 if (consumerd32_libdir[0] != '\0') {
1581 char *tmp;
1582 size_t tmplen;
1583
1584 tmp = getenv("LD_LIBRARY_PATH");
1585 if (!tmp) {
1586 tmp = "";
1587 }
1588 tmplen = strlen("LD_LIBRARY_PATH=")
1589 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1590 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1591 if (!tmpnew) {
1592 ret = -ENOMEM;
1593 goto error;
1594 }
1595 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1596 strcat(tmpnew, consumerd32_libdir);
1597 if (tmp[0] != '\0') {
1598 strcat(tmpnew, ":");
1599 strcat(tmpnew, tmp);
1600 }
1601 ret = putenv(tmpnew);
1602 if (ret) {
1603 ret = -errno;
1604 goto error;
1605 }
1606 }
1607 ret = execl(consumerd32_path, verbosity, "-u",
1608 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1609 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1610 NULL);
1611 if (consumerd32_libdir[0] != '\0') {
1612 free(tmpnew);
1613 }
1614 if (ret) {
1615 goto error;
1616 }
1617 break;
1618 }
1619 default:
1620 perror("unknown consumer type");
1621 exit(EXIT_FAILURE);
1622 }
1623 if (errno != 0) {
1624 perror("kernel start consumer exec");
1625 }
1626 exit(EXIT_FAILURE);
1627 } else if (pid > 0) {
1628 ret = pid;
1629 } else {
1630 perror("start consumer fork");
1631 ret = -errno;
1632 }
1633 error:
1634 return ret;
1635 }
1636
1637 /*
1638 * Spawn the consumerd daemon and session daemon thread.
1639 */
1640 static int start_consumerd(struct consumer_data *consumer_data)
1641 {
1642 int ret;
1643
1644 pthread_mutex_lock(&consumer_data->pid_mutex);
1645 if (consumer_data->pid != 0) {
1646 pthread_mutex_unlock(&consumer_data->pid_mutex);
1647 goto end;
1648 }
1649
1650 ret = spawn_consumerd(consumer_data);
1651 if (ret < 0) {
1652 ERR("Spawning consumerd failed");
1653 pthread_mutex_unlock(&consumer_data->pid_mutex);
1654 goto error;
1655 }
1656
1657 /* Setting up the consumer_data pid */
1658 consumer_data->pid = ret;
1659 DBG2("Consumer pid %d", consumer_data->pid);
1660 pthread_mutex_unlock(&consumer_data->pid_mutex);
1661
1662 DBG2("Spawning consumer control thread");
1663 ret = spawn_consumer_thread(consumer_data);
1664 if (ret < 0) {
1665 ERR("Fatal error spawning consumer control thread");
1666 goto error;
1667 }
1668
1669 end:
1670 return 0;
1671
1672 error:
1673 return ret;
1674 }
1675
1676 /*
1677 * modprobe_kernel_modules
1678 */
1679 static int modprobe_kernel_modules(void)
1680 {
1681 int ret = 0, i;
1682 char modprobe[256];
1683
1684 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1685 ret = snprintf(modprobe, sizeof(modprobe),
1686 "/sbin/modprobe %s%s",
1687 kernel_modules_list[i].required ? "" : "-q ",
1688 kernel_modules_list[i].name);
1689 if (ret < 0) {
1690 perror("snprintf modprobe");
1691 goto error;
1692 }
1693 modprobe[sizeof(modprobe) - 1] = '\0';
1694 ret = system(modprobe);
1695 if (ret == -1) {
1696 ERR("Unable to launch modprobe for module %s",
1697 kernel_modules_list[i].name);
1698 } else if (kernel_modules_list[i].required
1699 && WEXITSTATUS(ret) != 0) {
1700 ERR("Unable to load module %s",
1701 kernel_modules_list[i].name);
1702 } else {
1703 DBG("Modprobe successfully %s",
1704 kernel_modules_list[i].name);
1705 }
1706 }
1707
1708 error:
1709 return ret;
1710 }
1711
1712 /*
1713 * mount_debugfs
1714 */
1715 static int mount_debugfs(char *path)
1716 {
1717 int ret;
1718 char *type = "debugfs";
1719
1720 ret = mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1721 if (ret < 0) {
1722 PERROR("Cannot create debugfs path");
1723 goto error;
1724 }
1725
1726 ret = mount(type, path, type, 0, NULL);
1727 if (ret < 0) {
1728 PERROR("Cannot mount debugfs");
1729 goto error;
1730 }
1731
1732 DBG("Mounted debugfs successfully at %s", path);
1733
1734 error:
1735 return ret;
1736 }
1737
1738 /*
1739 * Setup necessary data for kernel tracer action.
1740 */
1741 static void init_kernel_tracer(void)
1742 {
1743 int ret;
1744 char *proc_mounts = "/proc/mounts";
1745 char line[256];
1746 char *debugfs_path = NULL, *lttng_path = NULL;
1747 FILE *fp;
1748
1749 /* Detect debugfs */
1750 fp = fopen(proc_mounts, "r");
1751 if (fp == NULL) {
1752 ERR("Unable to probe %s", proc_mounts);
1753 goto error;
1754 }
1755
1756 while (fgets(line, sizeof(line), fp) != NULL) {
1757 if (strstr(line, "debugfs") != NULL) {
1758 /* Remove first string */
1759 strtok(line, " ");
1760 /* Dup string here so we can reuse line later on */
1761 debugfs_path = strdup(strtok(NULL, " "));
1762 DBG("Got debugfs path : %s", debugfs_path);
1763 break;
1764 }
1765 }
1766
1767 fclose(fp);
1768
1769 /* Mount debugfs if needded */
1770 if (debugfs_path == NULL) {
1771 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1772 if (ret < 0) {
1773 perror("asprintf debugfs path");
1774 goto error;
1775 }
1776 ret = mount_debugfs(debugfs_path);
1777 if (ret < 0) {
1778 perror("Cannot mount debugfs");
1779 goto error;
1780 }
1781 }
1782
1783 /* Modprobe lttng kernel modules */
1784 ret = modprobe_kernel_modules();
1785 if (ret < 0) {
1786 goto error;
1787 }
1788
1789 /* Setup lttng kernel path */
1790 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1791 if (ret < 0) {
1792 perror("asprintf lttng path");
1793 goto error;
1794 }
1795
1796 /* Open debugfs lttng */
1797 kernel_tracer_fd = open(lttng_path, O_RDWR);
1798 if (kernel_tracer_fd < 0) {
1799 DBG("Failed to open %s", lttng_path);
1800 goto error;
1801 }
1802
1803 free(lttng_path);
1804 free(debugfs_path);
1805 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1806 return;
1807
1808 error:
1809 if (lttng_path) {
1810 free(lttng_path);
1811 }
1812 if (debugfs_path) {
1813 free(debugfs_path);
1814 }
1815 WARN("No kernel tracer available");
1816 kernel_tracer_fd = 0;
1817 return;
1818 }
1819
1820 /*
1821 * Init tracing by creating trace directory and sending fds kernel consumer.
1822 */
1823 static int init_kernel_tracing(struct ltt_kernel_session *session)
1824 {
1825 int ret = 0;
1826
1827 if (session->consumer_fds_sent == 0) {
1828 /*
1829 * Assign default kernel consumer socket if no consumer assigned to the
1830 * kernel session. At this point, it's NOT suppose to be 0 but this is
1831 * an extra security check.
1832 */
1833 if (session->consumer_fd == 0) {
1834 session->consumer_fd = kconsumer_data.cmd_sock;
1835 }
1836
1837 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1838 if (ret < 0) {
1839 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1840 goto error;
1841 }
1842
1843 session->consumer_fds_sent = 1;
1844 }
1845
1846 error:
1847 return ret;
1848 }
1849
1850 /*
1851 * Create an UST session and add it to the session ust list.
1852 */
1853 static int create_ust_session(struct ltt_session *session,
1854 struct lttng_domain *domain)
1855 {
1856 int ret;
1857 unsigned int uid;
1858 struct ltt_ust_session *lus = NULL;
1859
1860 switch (domain->type) {
1861 case LTTNG_DOMAIN_UST:
1862 break;
1863 default:
1864 ret = LTTCOMM_UNKNOWN_DOMAIN;
1865 goto error;
1866 }
1867
1868 DBG("Creating UST session");
1869
1870 uid = session->uid;
1871 lus = trace_ust_create_session(session->path, uid, domain);
1872 if (lus == NULL) {
1873 ret = LTTCOMM_UST_SESS_FAIL;
1874 goto error;
1875 }
1876
1877 ret = mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1878 geteuid(), allowed_group());
1879 if (ret < 0) {
1880 if (ret != -EEXIST) {
1881 ERR("Trace directory creation error");
1882 ret = LTTCOMM_UST_SESS_FAIL;
1883 goto error;
1884 }
1885 }
1886
1887 /* The domain type dictate different actions on session creation */
1888 switch (domain->type) {
1889 case LTTNG_DOMAIN_UST:
1890 /* No ustctl for the global UST domain */
1891 break;
1892 default:
1893 ERR("Unknown UST domain on create session %d", domain->type);
1894 goto error;
1895 }
1896 session->ust_session = lus;
1897
1898 return LTTCOMM_OK;
1899
1900 error:
1901 free(lus);
1902 return ret;
1903 }
1904
1905 /*
1906 * Create a kernel tracer session then create the default channel.
1907 */
1908 static int create_kernel_session(struct ltt_session *session)
1909 {
1910 int ret;
1911
1912 DBG("Creating kernel session");
1913
1914 ret = kernel_create_session(session, kernel_tracer_fd);
1915 if (ret < 0) {
1916 ret = LTTCOMM_KERN_SESS_FAIL;
1917 goto error;
1918 }
1919
1920 /* Set kernel consumer socket fd */
1921 if (kconsumer_data.cmd_sock) {
1922 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1923 }
1924
1925 ret = mkdir_recursive(session->kernel_session->trace_path,
1926 S_IRWXU | S_IRWXG, geteuid(), allowed_group());
1927 if (ret < 0) {
1928 if (ret != -EEXIST) {
1929 ERR("Trace directory creation error");
1930 goto error;
1931 }
1932 }
1933
1934 error:
1935 return ret;
1936 }
1937
1938 /*
1939 * Using the session list, filled a lttng_session array to send back to the
1940 * client for session listing.
1941 *
1942 * The session list lock MUST be acquired before calling this function. Use
1943 * session_lock_list() and session_unlock_list().
1944 */
1945 static void list_lttng_sessions(struct lttng_session *sessions)
1946 {
1947 int i = 0;
1948 struct ltt_session *session;
1949
1950 DBG("Getting all available session");
1951 /*
1952 * Iterate over session list and append data after the control struct in
1953 * the buffer.
1954 */
1955 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1956 strncpy(sessions[i].path, session->path, PATH_MAX);
1957 sessions[i].path[PATH_MAX - 1] = '\0';
1958 strncpy(sessions[i].name, session->name, NAME_MAX);
1959 sessions[i].name[NAME_MAX - 1] = '\0';
1960 sessions[i].enabled = session->enabled;
1961 i++;
1962 }
1963 }
1964
1965 /*
1966 * Fill lttng_channel array of all channels.
1967 */
1968 static void list_lttng_channels(int domain, struct ltt_session *session,
1969 struct lttng_channel *channels)
1970 {
1971 int i = 0;
1972 struct ltt_kernel_channel *kchan;
1973
1974 DBG("Listing channels for session %s", session->name);
1975
1976 switch (domain) {
1977 case LTTNG_DOMAIN_KERNEL:
1978 /* Kernel channels */
1979 if (session->kernel_session != NULL) {
1980 cds_list_for_each_entry(kchan,
1981 &session->kernel_session->channel_list.head, list) {
1982 /* Copy lttng_channel struct to array */
1983 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
1984 channels[i].enabled = kchan->enabled;
1985 i++;
1986 }
1987 }
1988 break;
1989 case LTTNG_DOMAIN_UST:
1990 {
1991 struct cds_lfht_iter iter;
1992 struct ltt_ust_channel *uchan;
1993
1994 cds_lfht_for_each_entry(session->ust_session->domain_global.channels,
1995 &iter, uchan, node) {
1996 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
1997 channels[i].attr.overwrite = uchan->attr.overwrite;
1998 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
1999 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2000 channels[i].attr.switch_timer_interval =
2001 uchan->attr.switch_timer_interval;
2002 channels[i].attr.read_timer_interval =
2003 uchan->attr.read_timer_interval;
2004 channels[i].enabled = uchan->enabled;
2005 switch (uchan->attr.output) {
2006 case LTTNG_UST_MMAP:
2007 default:
2008 channels[i].attr.output = LTTNG_EVENT_MMAP;
2009 break;
2010 }
2011 i++;
2012 }
2013 break;
2014 }
2015 default:
2016 break;
2017 }
2018 }
2019
2020 /*
2021 * Create a list of ust global domain events.
2022 */
2023 static int list_lttng_ust_global_events(char *channel_name,
2024 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2025 {
2026 int i = 0, ret = 0;
2027 unsigned int nb_event = 0;
2028 struct cds_lfht_iter iter;
2029 struct cds_lfht_node *node;
2030 struct ltt_ust_channel *uchan;
2031 struct ltt_ust_event *uevent;
2032 struct lttng_event *tmp;
2033
2034 DBG("Listing UST global events for channel %s", channel_name);
2035
2036 rcu_read_lock();
2037
2038 node = hashtable_lookup(ust_global->channels, (void *) channel_name,
2039 strlen(channel_name), &iter);
2040 if (node == NULL) {
2041 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2042 goto error;
2043 }
2044
2045 uchan = caa_container_of(node, struct ltt_ust_channel, node);
2046
2047 nb_event += hashtable_get_count(uchan->events);
2048
2049 if (nb_event == 0) {
2050 ret = nb_event;
2051 goto error;
2052 }
2053
2054 DBG3("Listing UST global %d events", nb_event);
2055
2056 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2057 if (tmp == NULL) {
2058 ret = -LTTCOMM_FATAL;
2059 goto error;
2060 }
2061
2062 cds_lfht_for_each_entry(uchan->events, &iter, uevent, node) {
2063 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2064 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2065 tmp[i].enabled = uevent->enabled;
2066 switch (uevent->attr.instrumentation) {
2067 case LTTNG_UST_TRACEPOINT:
2068 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2069 break;
2070 case LTTNG_UST_PROBE:
2071 tmp[i].type = LTTNG_EVENT_PROBE;
2072 break;
2073 case LTTNG_UST_FUNCTION:
2074 tmp[i].type = LTTNG_EVENT_FUNCTION;
2075 break;
2076 case LTTNG_UST_TRACEPOINT_LOGLEVEL:
2077 /* TODO */
2078 ret = -LTTCOMM_NOT_IMPLEMENTED;
2079 goto error;
2080 break;
2081 }
2082 i++;
2083 }
2084
2085 ret = nb_event;
2086 *events = tmp;
2087
2088 error:
2089 rcu_read_unlock();
2090 return ret;
2091 }
2092
2093 /*
2094 * Fill lttng_event array of all kernel events in the channel.
2095 */
2096 static int list_lttng_kernel_events(char *channel_name,
2097 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2098 {
2099 int i = 0, ret;
2100 unsigned int nb_event;
2101 struct ltt_kernel_event *event;
2102 struct ltt_kernel_channel *kchan;
2103
2104 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2105 if (kchan == NULL) {
2106 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2107 goto error;
2108 }
2109
2110 nb_event = kchan->event_count;
2111
2112 DBG("Listing events for channel %s", kchan->channel->name);
2113
2114 if (nb_event == 0) {
2115 ret = nb_event;
2116 goto error;
2117 }
2118
2119 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2120 if (*events == NULL) {
2121 ret = LTTCOMM_FATAL;
2122 goto error;
2123 }
2124
2125 /* Kernel channels */
2126 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2127 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2128 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2129 (*events)[i].enabled = event->enabled;
2130 switch (event->event->instrumentation) {
2131 case LTTNG_KERNEL_TRACEPOINT:
2132 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2133 break;
2134 case LTTNG_KERNEL_KPROBE:
2135 case LTTNG_KERNEL_KRETPROBE:
2136 (*events)[i].type = LTTNG_EVENT_PROBE;
2137 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2138 sizeof(struct lttng_kernel_kprobe));
2139 break;
2140 case LTTNG_KERNEL_FUNCTION:
2141 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2142 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2143 sizeof(struct lttng_kernel_function));
2144 break;
2145 case LTTNG_KERNEL_NOOP:
2146 (*events)[i].type = LTTNG_EVENT_NOOP;
2147 break;
2148 case LTTNG_KERNEL_SYSCALL:
2149 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2150 break;
2151 case LTTNG_KERNEL_ALL:
2152 assert(0);
2153 break;
2154 }
2155 i++;
2156 }
2157
2158 return nb_event;
2159
2160 error:
2161 return ret;
2162 }
2163
2164 /*
2165 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2166 */
2167 static int cmd_disable_channel(struct ltt_session *session,
2168 int domain, char *channel_name)
2169 {
2170 int ret;
2171 struct ltt_ust_session *usess;
2172
2173 usess = session->ust_session;
2174
2175 switch (domain) {
2176 case LTTNG_DOMAIN_KERNEL:
2177 {
2178 ret = channel_kernel_disable(session->kernel_session,
2179 channel_name);
2180 if (ret != LTTCOMM_OK) {
2181 goto error;
2182 }
2183
2184 kernel_wait_quiescent(kernel_tracer_fd);
2185 break;
2186 }
2187 case LTTNG_DOMAIN_UST:
2188 {
2189 struct ltt_ust_channel *uchan;
2190
2191 /* Get channel in global UST domain HT */
2192 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2193 channel_name);
2194 if (uchan == NULL) {
2195 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2196 goto error;
2197 }
2198
2199 /* Already disabled */
2200 if (!uchan->enabled) {
2201 DBG2("UST channel %s already disabled", channel_name);
2202 break;
2203 }
2204
2205 ret = ust_app_disable_channel_glb(usess, uchan);
2206 if (ret < 0) {
2207 ret = LTTCOMM_UST_DISABLE_FAIL;
2208 goto error;
2209 }
2210
2211 uchan->enabled = 0;
2212
2213 break;
2214 }
2215 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2216 case LTTNG_DOMAIN_UST_EXEC_NAME:
2217 case LTTNG_DOMAIN_UST_PID:
2218 ret = LTTCOMM_NOT_IMPLEMENTED;
2219 goto error;
2220 default:
2221 ret = LTTCOMM_UNKNOWN_DOMAIN;
2222 goto error;
2223 }
2224
2225 ret = LTTCOMM_OK;
2226
2227 error:
2228 return ret;
2229 }
2230
2231 /*
2232 * Copy channel from attributes and set it in the application channel list.
2233 */
2234 /*
2235 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
2236 struct lttng_channel *attr, struct ust_app *app)
2237 {
2238 int ret;
2239 struct ltt_ust_channel *uchan, *new_chan;
2240
2241 uchan = trace_ust_get_channel_by_key(usess->channels, attr->name);
2242 if (uchan == NULL) {
2243 ret = LTTCOMM_FATAL;
2244 goto error;
2245 }
2246
2247 new_chan = trace_ust_create_channel(attr, usess->path);
2248 if (new_chan == NULL) {
2249 PERROR("malloc ltt_ust_channel");
2250 ret = LTTCOMM_FATAL;
2251 goto error;
2252 }
2253
2254 ret = channel_ust_copy(new_chan, uchan);
2255 if (ret < 0) {
2256 ret = LTTCOMM_FATAL;
2257 goto error;
2258 }
2259
2260 error:
2261 return ret;
2262 }
2263 */
2264
2265 /*
2266 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2267 */
2268 static int cmd_enable_channel(struct ltt_session *session,
2269 int domain, struct lttng_channel *attr)
2270 {
2271 int ret;
2272 struct ltt_ust_session *usess = session->ust_session;
2273
2274 DBG("Enabling channel %s for session %s", attr->name, session->name);
2275
2276 switch (domain) {
2277 case LTTNG_DOMAIN_KERNEL:
2278 {
2279 struct ltt_kernel_channel *kchan;
2280
2281 kchan = trace_kernel_get_channel_by_name(attr->name,
2282 session->kernel_session);
2283 if (kchan == NULL) {
2284 ret = channel_kernel_create(session->kernel_session,
2285 attr, kernel_poll_pipe[1]);
2286 } else {
2287 ret = channel_kernel_enable(session->kernel_session, kchan);
2288 }
2289
2290 if (ret != LTTCOMM_OK) {
2291 goto error;
2292 }
2293
2294 kernel_wait_quiescent(kernel_tracer_fd);
2295 break;
2296 }
2297 case LTTNG_DOMAIN_UST:
2298 {
2299 struct ltt_ust_channel *uchan;
2300
2301 DBG2("Enabling channel for LTTNG_DOMAIN_UST");
2302
2303 /* Get channel in global UST domain HT */
2304 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2305 attr->name);
2306 if (uchan == NULL) {
2307 uchan = trace_ust_create_channel(attr, usess->pathname);
2308 if (uchan == NULL) {
2309 ret = LTTCOMM_UST_CHAN_FAIL;
2310 goto error;
2311 }
2312
2313 /* Add channel to all registered applications */
2314 ret = ust_app_create_channel_glb(usess, uchan);
2315 if (ret != 0) {
2316 ret = LTTCOMM_UST_CHAN_FAIL;
2317 goto error;
2318 }
2319
2320 rcu_read_lock();
2321 hashtable_add_unique(usess->domain_global.channels, &uchan->node);
2322 rcu_read_unlock();
2323
2324 DBG2("UST channel %s added to global domain HT", attr->name);
2325 } else {
2326 /* If already enabled, everything is OK */
2327 if (uchan->enabled) {
2328 break;
2329 }
2330
2331 ret = ust_app_enable_channel_glb(usess, uchan);
2332 if (ret < 0) {
2333 if (ret != -EEXIST) {
2334 ret = LTTCOMM_UST_CHAN_ENABLE_FAIL;
2335 goto error;
2336 } else {
2337 ret = LTTCOMM_OK;
2338 }
2339 }
2340 }
2341
2342 uchan->enabled = 1;
2343
2344 break;
2345 }
2346 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2347 case LTTNG_DOMAIN_UST_EXEC_NAME:
2348 case LTTNG_DOMAIN_UST_PID:
2349 ret = LTTCOMM_NOT_IMPLEMENTED;
2350 goto error;
2351 default:
2352 ret = LTTCOMM_UNKNOWN_DOMAIN;
2353 goto error;
2354 }
2355
2356 ret = LTTCOMM_OK;
2357
2358 error:
2359 return ret;
2360 }
2361
2362 /*
2363 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2364 */
2365 static int cmd_disable_event(struct ltt_session *session, int domain,
2366 char *channel_name, char *event_name)
2367 {
2368 int ret;
2369
2370 switch (domain) {
2371 case LTTNG_DOMAIN_KERNEL:
2372 {
2373 struct ltt_kernel_channel *kchan;
2374 struct ltt_kernel_session *ksess;
2375
2376 ksess = session->kernel_session;
2377
2378 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2379 if (kchan == NULL) {
2380 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2381 goto error;
2382 }
2383
2384 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2385 if (ret != LTTCOMM_OK) {
2386 goto error;
2387 }
2388
2389 kernel_wait_quiescent(kernel_tracer_fd);
2390 break;
2391 }
2392 case LTTNG_DOMAIN_UST:
2393 {
2394 struct ltt_ust_session *usess;
2395 struct ltt_ust_channel *uchan;
2396 struct ltt_ust_event *uevent;
2397
2398 usess = session->ust_session;
2399
2400 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2401 channel_name);
2402 if (uchan == NULL) {
2403 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2404 goto error;
2405 }
2406
2407 uevent = trace_ust_find_event_by_name(uchan->events, event_name);
2408 if (uevent == NULL) {
2409 ret = LTTCOMM_UST_EVENT_NOT_FOUND;
2410 goto error;
2411 }
2412
2413 ret = ust_app_disable_event_glb(usess, uchan, uevent);
2414 if (ret < 0) {
2415 ret = LTTCOMM_UST_DISABLE_FAIL;
2416 goto error;
2417 }
2418
2419 uevent->enabled = 0;
2420
2421 DBG2("Disable UST event %s in channel %s completed", event_name,
2422 channel_name);
2423
2424 break;
2425 }
2426 case LTTNG_DOMAIN_UST_EXEC_NAME:
2427 case LTTNG_DOMAIN_UST_PID:
2428 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2429 default:
2430 ret = LTTCOMM_NOT_IMPLEMENTED;
2431 goto error;
2432 }
2433
2434 ret = LTTCOMM_OK;
2435
2436 error:
2437 return ret;
2438 }
2439
2440 /*
2441 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2442 */
2443 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2444 char *channel_name)
2445 {
2446 int ret;
2447
2448 switch (domain) {
2449 case LTTNG_DOMAIN_KERNEL:
2450 {
2451 struct ltt_kernel_session *ksess;
2452 struct ltt_kernel_channel *kchan;
2453
2454 ksess = session->kernel_session;
2455
2456 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2457 if (kchan == NULL) {
2458 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2459 goto error;
2460 }
2461
2462 ret = event_kernel_disable_all(ksess, kchan);
2463 if (ret != LTTCOMM_OK) {
2464 goto error;
2465 }
2466
2467 kernel_wait_quiescent(kernel_tracer_fd);
2468 break;
2469 }
2470 case LTTNG_DOMAIN_UST:
2471 {
2472 struct ltt_ust_session *usess;
2473 struct ltt_ust_channel *uchan;
2474
2475 usess = session->ust_session;
2476
2477 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2478 channel_name);
2479 if (uchan == NULL) {
2480 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2481 goto error;
2482 }
2483
2484 ret = ust_app_disable_all_event_glb(usess, uchan);
2485 if (ret < 0) {
2486 ret = LTTCOMM_UST_DISABLE_FAIL;
2487 goto error;
2488 }
2489
2490 DBG2("Disable all UST event in channel %s completed", channel_name);
2491
2492 break;
2493 }
2494 case LTTNG_DOMAIN_UST_EXEC_NAME:
2495 case LTTNG_DOMAIN_UST_PID:
2496 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2497 default:
2498 ret = LTTCOMM_NOT_IMPLEMENTED;
2499 goto error;
2500 }
2501
2502 ret = LTTCOMM_OK;
2503
2504 error:
2505 return ret;
2506 }
2507
2508 /*
2509 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2510 */
2511 static int cmd_add_context(struct ltt_session *session, int domain,
2512 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2513 {
2514 int ret;
2515
2516 switch (domain) {
2517 case LTTNG_DOMAIN_KERNEL:
2518 /* Add kernel context to kernel tracer */
2519 ret = context_kernel_add(session->kernel_session, ctx,
2520 event_name, channel_name);
2521 if (ret != LTTCOMM_OK) {
2522 goto error;
2523 }
2524 break;
2525 case LTTNG_DOMAIN_UST:
2526 {
2527 struct ltt_ust_session *usess = session->ust_session;
2528
2529 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2530 if (ret != LTTCOMM_OK) {
2531 goto error;
2532 }
2533 break;
2534 }
2535 case LTTNG_DOMAIN_UST_EXEC_NAME:
2536 case LTTNG_DOMAIN_UST_PID:
2537 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2538 default:
2539 ret = LTTCOMM_NOT_IMPLEMENTED;
2540 goto error;
2541 }
2542
2543 ret = LTTCOMM_OK;
2544
2545 error:
2546 return ret;
2547 }
2548
2549 /*
2550 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2551 */
2552 static int cmd_enable_event(struct ltt_session *session, int domain,
2553 char *channel_name, struct lttng_event *event)
2554 {
2555 int ret;
2556 struct lttng_channel *attr;
2557 struct ltt_ust_session *usess = session->ust_session;
2558
2559 switch (domain) {
2560 case LTTNG_DOMAIN_KERNEL:
2561 {
2562 struct ltt_kernel_channel *kchan;
2563
2564 kchan = trace_kernel_get_channel_by_name(channel_name,
2565 session->kernel_session);
2566 if (kchan == NULL) {
2567 attr = channel_new_default_attr(domain);
2568 if (attr == NULL) {
2569 ret = LTTCOMM_FATAL;
2570 goto error;
2571 }
2572 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2573
2574 /* This call will notify the kernel thread */
2575 ret = channel_kernel_create(session->kernel_session,
2576 attr, kernel_poll_pipe[1]);
2577 if (ret != LTTCOMM_OK) {
2578 free(attr);
2579 goto error;
2580 }
2581 free(attr);
2582 }
2583
2584 /* Get the newly created kernel channel pointer */
2585 kchan = trace_kernel_get_channel_by_name(channel_name,
2586 session->kernel_session);
2587 if (kchan == NULL) {
2588 /* This sould not happen... */
2589 ret = LTTCOMM_FATAL;
2590 goto error;
2591 }
2592
2593 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2594 event);
2595 if (ret != LTTCOMM_OK) {
2596 goto error;
2597 }
2598
2599 kernel_wait_quiescent(kernel_tracer_fd);
2600 break;
2601 }
2602 case LTTNG_DOMAIN_UST:
2603 {
2604 struct lttng_channel *attr;
2605 struct ltt_ust_channel *uchan;
2606
2607 /* Get channel from global UST domain */
2608 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2609 channel_name);
2610 if (uchan == NULL) {
2611 /* Create default channel */
2612 attr = channel_new_default_attr(domain);
2613 if (attr == NULL) {
2614 ret = LTTCOMM_FATAL;
2615 goto error;
2616 }
2617 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2618 attr->name[NAME_MAX - 1] = '\0';
2619
2620 /* Use the internal command enable channel */
2621 ret = cmd_enable_channel(session, domain, attr);
2622 if (ret != LTTCOMM_OK) {
2623 free(attr);
2624 goto error;
2625 }
2626 free(attr);
2627
2628 /* Get the newly created channel reference back */
2629 uchan = trace_ust_find_channel_by_name(
2630 usess->domain_global.channels, channel_name);
2631 if (uchan == NULL) {
2632 /* Something is really wrong */
2633 ret = LTTCOMM_FATAL;
2634 goto error;
2635 }
2636 }
2637
2638 /* At this point, the session and channel exist on the tracer */
2639
2640 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2641 if (ret != LTTCOMM_OK) {
2642 goto error;
2643 }
2644 break;
2645 }
2646 case LTTNG_DOMAIN_UST_EXEC_NAME:
2647 case LTTNG_DOMAIN_UST_PID:
2648 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2649 default:
2650 ret = LTTCOMM_NOT_IMPLEMENTED;
2651 goto error;
2652 }
2653
2654 ret = LTTCOMM_OK;
2655
2656 error:
2657 return ret;
2658 }
2659
2660 /*
2661 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2662 */
2663 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2664 char *channel_name, int event_type)
2665 {
2666 int ret;
2667 struct ltt_kernel_channel *kchan;
2668
2669 switch (domain) {
2670 case LTTNG_DOMAIN_KERNEL:
2671 kchan = trace_kernel_get_channel_by_name(channel_name,
2672 session->kernel_session);
2673 if (kchan == NULL) {
2674 /* This call will notify the kernel thread */
2675 ret = channel_kernel_create(session->kernel_session, NULL,
2676 kernel_poll_pipe[1]);
2677 if (ret != LTTCOMM_OK) {
2678 goto error;
2679 }
2680
2681 /* Get the newly created kernel channel pointer */
2682 kchan = trace_kernel_get_channel_by_name(channel_name,
2683 session->kernel_session);
2684 if (kchan == NULL) {
2685 /* This sould not happen... */
2686 ret = LTTCOMM_FATAL;
2687 goto error;
2688 }
2689
2690 }
2691
2692 switch (event_type) {
2693 case LTTNG_KERNEL_SYSCALL:
2694 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2695 kchan, kernel_tracer_fd);
2696 break;
2697 case LTTNG_KERNEL_TRACEPOINT:
2698 /*
2699 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2700 * events already registered to the channel.
2701 */
2702 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2703 kchan, kernel_tracer_fd);
2704 break;
2705 case LTTNG_KERNEL_ALL:
2706 /* Enable syscalls and tracepoints */
2707 ret = event_kernel_enable_all(session->kernel_session,
2708 kchan, kernel_tracer_fd);
2709 break;
2710 default:
2711 ret = LTTCOMM_KERN_ENABLE_FAIL;
2712 goto error;
2713 }
2714
2715 /* Manage return value */
2716 if (ret != LTTCOMM_OK) {
2717 goto error;
2718 }
2719
2720 kernel_wait_quiescent(kernel_tracer_fd);
2721 break;
2722 default:
2723 /* TODO: Userspace tracing */
2724 ret = LTTCOMM_NOT_IMPLEMENTED;
2725 goto error;
2726 }
2727
2728 ret = LTTCOMM_OK;
2729
2730 error:
2731 return ret;
2732 }
2733
2734 /*
2735 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2736 */
2737 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2738 {
2739 int ret;
2740 ssize_t nb_events = 0;
2741
2742 switch (domain) {
2743 case LTTNG_DOMAIN_KERNEL:
2744 nb_events = kernel_list_events(kernel_tracer_fd, events);
2745 if (nb_events < 0) {
2746 ret = LTTCOMM_KERN_LIST_FAIL;
2747 goto error;
2748 }
2749 break;
2750 case LTTNG_DOMAIN_UST:
2751 nb_events = ust_app_list_events(events);
2752 if (nb_events < 0) {
2753 ret = LTTCOMM_UST_LIST_FAIL;
2754 goto error;
2755 }
2756 break;
2757 default:
2758 ret = LTTCOMM_NOT_IMPLEMENTED;
2759 goto error;
2760 }
2761
2762 return nb_events;
2763
2764 error:
2765 /* Return negative value to differentiate return code */
2766 return -ret;
2767 }
2768
2769 /*
2770 * Command LTTNG_START_TRACE processed by the client thread.
2771 */
2772 static int cmd_start_trace(struct ltt_session *session)
2773 {
2774 int ret;
2775 struct ltt_kernel_session *ksession;
2776 struct ltt_ust_session *usess;
2777
2778 /* Short cut */
2779 ksession = session->kernel_session;
2780 usess = session->ust_session;
2781
2782 if (session->enabled)
2783 return LTTCOMM_UST_START_FAIL;
2784 session->enabled = 1;
2785
2786 /* Kernel tracing */
2787 if (ksession != NULL) {
2788 struct ltt_kernel_channel *kchan;
2789
2790 /* Open kernel metadata */
2791 if (ksession->metadata == NULL) {
2792 ret = kernel_open_metadata(ksession, ksession->trace_path);
2793 if (ret < 0) {
2794 ret = LTTCOMM_KERN_META_FAIL;
2795 goto error;
2796 }
2797 }
2798
2799 /* Open kernel metadata stream */
2800 if (ksession->metadata_stream_fd == 0) {
2801 ret = kernel_open_metadata_stream(ksession);
2802 if (ret < 0) {
2803 ERR("Kernel create metadata stream failed");
2804 ret = LTTCOMM_KERN_STREAM_FAIL;
2805 goto error;
2806 }
2807 }
2808
2809 /* For each channel */
2810 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2811 if (kchan->stream_count == 0) {
2812 ret = kernel_open_channel_stream(kchan);
2813 if (ret < 0) {
2814 ret = LTTCOMM_KERN_STREAM_FAIL;
2815 goto error;
2816 }
2817 /* Update the stream global counter */
2818 ksession->stream_count_global += ret;
2819 }
2820 }
2821
2822 /* Setup kernel consumer socket and send fds to it */
2823 ret = init_kernel_tracing(ksession);
2824 if (ret < 0) {
2825 ret = LTTCOMM_KERN_START_FAIL;
2826 goto error;
2827 }
2828
2829 /* This start the kernel tracing */
2830 ret = kernel_start_session(ksession);
2831 if (ret < 0) {
2832 ret = LTTCOMM_KERN_START_FAIL;
2833 goto error;
2834 }
2835
2836 /* Quiescent wait after starting trace */
2837 kernel_wait_quiescent(kernel_tracer_fd);
2838 }
2839
2840 /* Flag session that trace should start automatically */
2841 if (usess) {
2842 usess->start_trace = 1;
2843
2844 ret = ust_app_start_trace_all(usess);
2845 if (ret < 0) {
2846 ret = LTTCOMM_UST_START_FAIL;
2847 goto error;
2848 }
2849 }
2850
2851 ret = LTTCOMM_OK;
2852
2853 error:
2854 return ret;
2855 }
2856
2857 /*
2858 * Command LTTNG_STOP_TRACE processed by the client thread.
2859 */
2860 static int cmd_stop_trace(struct ltt_session *session)
2861 {
2862 int ret;
2863 struct ltt_kernel_channel *kchan;
2864 struct ltt_kernel_session *ksession;
2865 struct ltt_ust_session *usess;
2866
2867 /* Short cut */
2868 ksession = session->kernel_session;
2869 usess = session->ust_session;
2870
2871 if (!session->enabled)
2872 return LTTCOMM_UST_START_FAIL;
2873 session->enabled = 0;
2874
2875 /* Kernel tracer */
2876 if (ksession != NULL) {
2877 DBG("Stop kernel tracing");
2878
2879 /* Flush all buffers before stopping */
2880 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2881 if (ret < 0) {
2882 ERR("Kernel metadata flush failed");
2883 }
2884
2885 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2886 ret = kernel_flush_buffer(kchan);
2887 if (ret < 0) {
2888 ERR("Kernel flush buffer error");
2889 }
2890 }
2891
2892 ret = kernel_stop_session(ksession);
2893 if (ret < 0) {
2894 ret = LTTCOMM_KERN_STOP_FAIL;
2895 goto error;
2896 }
2897
2898 kernel_wait_quiescent(kernel_tracer_fd);
2899 }
2900
2901 if (usess) {
2902 usess->start_trace = 0;
2903
2904 ret = ust_app_stop_trace_all(usess);
2905 if (ret < 0) {
2906 ret = LTTCOMM_UST_START_FAIL;
2907 goto error;
2908 }
2909 }
2910
2911 ret = LTTCOMM_OK;
2912
2913 error:
2914 return ret;
2915 }
2916
2917 /*
2918 * Command LTTNG_CREATE_SESSION processed by the client thread.
2919 */
2920 static int cmd_create_session(char *name, char *path)
2921 {
2922 int ret;
2923
2924 ret = session_create(name, path);
2925 if (ret != LTTCOMM_OK) {
2926 goto error;
2927 }
2928
2929 ret = LTTCOMM_OK;
2930
2931 error:
2932 return ret;
2933 }
2934
2935 /*
2936 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2937 */
2938 static int cmd_destroy_session(struct ltt_session *session, char *name)
2939 {
2940 int ret;
2941
2942 /* Clean kernel session teardown */
2943 teardown_kernel_session(session);
2944 /* UST session teardown */
2945 teardown_ust_session(session);
2946
2947 /*
2948 * Must notify the kernel thread here to update it's poll setin order
2949 * to remove the channel(s)' fd just destroyed.
2950 */
2951 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2952 if (ret < 0) {
2953 perror("write kernel poll pipe");
2954 }
2955
2956 ret = session_destroy(session);
2957
2958 return ret;
2959 }
2960
2961 /*
2962 * Command LTTNG_CALIBRATE processed by the client thread.
2963 */
2964 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2965 {
2966 int ret;
2967
2968 switch (domain) {
2969 case LTTNG_DOMAIN_KERNEL:
2970 {
2971 struct lttng_kernel_calibrate kcalibrate;
2972
2973 kcalibrate.type = calibrate->type;
2974 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2975 if (ret < 0) {
2976 ret = LTTCOMM_KERN_ENABLE_FAIL;
2977 goto error;
2978 }
2979 break;
2980 }
2981 default:
2982 /* TODO: Userspace tracing */
2983 ret = LTTCOMM_NOT_IMPLEMENTED;
2984 goto error;
2985 }
2986
2987 ret = LTTCOMM_OK;
2988
2989 error:
2990 return ret;
2991 }
2992
2993 /*
2994 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2995 */
2996 static int cmd_register_consumer(struct ltt_session *session, int domain,
2997 char *sock_path)
2998 {
2999 int ret, sock;
3000
3001 switch (domain) {
3002 case LTTNG_DOMAIN_KERNEL:
3003 /* Can't register a consumer if there is already one */
3004 if (session->kernel_session->consumer_fd != 0) {
3005 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3006 goto error;
3007 }
3008
3009 sock = lttcomm_connect_unix_sock(sock_path);
3010 if (sock < 0) {
3011 ret = LTTCOMM_CONNECT_FAIL;
3012 goto error;
3013 }
3014
3015 session->kernel_session->consumer_fd = sock;
3016 break;
3017 default:
3018 /* TODO: Userspace tracing */
3019 ret = LTTCOMM_NOT_IMPLEMENTED;
3020 goto error;
3021 }
3022
3023 ret = LTTCOMM_OK;
3024
3025 error:
3026 return ret;
3027 }
3028
3029 /*
3030 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3031 */
3032 static ssize_t cmd_list_domains(struct ltt_session *session,
3033 struct lttng_domain **domains)
3034 {
3035 int ret, index = 0;
3036 ssize_t nb_dom = 0;
3037
3038 if (session->kernel_session != NULL) {
3039 DBG3("Listing domains found kernel domain");
3040 nb_dom++;
3041 }
3042
3043 if (session->ust_session != NULL) {
3044 DBG3("Listing domains found UST global domain");
3045 nb_dom++;
3046 }
3047
3048 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3049 if (*domains == NULL) {
3050 ret = -LTTCOMM_FATAL;
3051 goto error;
3052 }
3053
3054 if (session->kernel_session != NULL) {
3055 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3056 index++;
3057 }
3058
3059 if (session->ust_session != NULL) {
3060 (*domains)[index].type = LTTNG_DOMAIN_UST;
3061 index++;
3062 }
3063
3064 return nb_dom;
3065
3066 error:
3067 return ret;
3068 }
3069
3070 /*
3071 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3072 */
3073 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3074 struct lttng_channel **channels)
3075 {
3076 int ret;
3077 ssize_t nb_chan = 0;
3078
3079 switch (domain) {
3080 case LTTNG_DOMAIN_KERNEL:
3081 if (session->kernel_session != NULL) {
3082 nb_chan = session->kernel_session->channel_count;
3083 }
3084 DBG3("Number of kernel channels %zd", nb_chan);
3085 break;
3086 case LTTNG_DOMAIN_UST:
3087 if (session->ust_session != NULL) {
3088 nb_chan = hashtable_get_count(
3089 session->ust_session->domain_global.channels);
3090 }
3091 DBG3("Number of UST global channels %zd", nb_chan);
3092 break;
3093 default:
3094 *channels = NULL;
3095 ret = -LTTCOMM_NOT_IMPLEMENTED;
3096 goto error;
3097 }
3098
3099 if (nb_chan > 0) {
3100 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3101 if (*channels == NULL) {
3102 ret = -LTTCOMM_FATAL;
3103 goto error;
3104 }
3105
3106 list_lttng_channels(domain, session, *channels);
3107 } else {
3108 *channels = NULL;
3109 }
3110
3111 return nb_chan;
3112
3113 error:
3114 return ret;
3115 }
3116
3117 /*
3118 * Command LTTNG_LIST_EVENTS processed by the client thread.
3119 */
3120 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3121 char *channel_name, struct lttng_event **events)
3122 {
3123 int ret = 0;
3124 ssize_t nb_event = 0;
3125
3126 switch (domain) {
3127 case LTTNG_DOMAIN_KERNEL:
3128 if (session->kernel_session != NULL) {
3129 nb_event = list_lttng_kernel_events(channel_name,
3130 session->kernel_session, events);
3131 }
3132 break;
3133 case LTTNG_DOMAIN_UST:
3134 {
3135 if (session->ust_session != NULL) {
3136 nb_event = list_lttng_ust_global_events(channel_name,
3137 &session->ust_session->domain_global, events);
3138 }
3139 break;
3140 }
3141 default:
3142 ret = -LTTCOMM_NOT_IMPLEMENTED;
3143 goto error;
3144 }
3145
3146 ret = nb_event;
3147
3148 error:
3149 return ret;
3150 }
3151
3152 /*
3153 * Process the command requested by the lttng client within the command
3154 * context structure. This function make sure that the return structure (llm)
3155 * is set and ready for transmission before returning.
3156 *
3157 * Return any error encountered or 0 for success.
3158 */
3159 static int process_client_msg(struct command_ctx *cmd_ctx)
3160 {
3161 int ret = LTTCOMM_OK;
3162 int need_tracing_session = 1;
3163
3164 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3165
3166 /*
3167 * Check for command that don't needs to allocate a returned payload. We do
3168 * this here so we don't have to make the call for no payload at each
3169 * command.
3170 */
3171 switch(cmd_ctx->lsm->cmd_type) {
3172 case LTTNG_LIST_SESSIONS:
3173 case LTTNG_LIST_TRACEPOINTS:
3174 case LTTNG_LIST_DOMAINS:
3175 case LTTNG_LIST_CHANNELS:
3176 case LTTNG_LIST_EVENTS:
3177 break;
3178 default:
3179 /* Setup lttng message with no payload */
3180 ret = setup_lttng_msg(cmd_ctx, 0);
3181 if (ret < 0) {
3182 /* This label does not try to unlock the session */
3183 goto init_setup_error;
3184 }
3185 }
3186
3187 /* Commands that DO NOT need a session. */
3188 switch (cmd_ctx->lsm->cmd_type) {
3189 case LTTNG_CALIBRATE:
3190 case LTTNG_CREATE_SESSION:
3191 case LTTNG_LIST_SESSIONS:
3192 case LTTNG_LIST_TRACEPOINTS:
3193 need_tracing_session = 0;
3194 break;
3195 default:
3196 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3197 session_lock_list();
3198 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3199 session_unlock_list();
3200 if (cmd_ctx->session == NULL) {
3201 if (cmd_ctx->lsm->session.name != NULL) {
3202 ret = LTTCOMM_SESS_NOT_FOUND;
3203 } else {
3204 /* If no session name specified */
3205 ret = LTTCOMM_SELECT_SESS;
3206 }
3207 goto error;
3208 } else {
3209 /* Acquire lock for the session */
3210 session_lock(cmd_ctx->session);
3211 }
3212 break;
3213 }
3214
3215 /*
3216 * Check domain type for specific "pre-action".
3217 */
3218 switch (cmd_ctx->lsm->domain.type) {
3219 case LTTNG_DOMAIN_KERNEL:
3220 /* Kernel tracer check */
3221 if (kernel_tracer_fd == 0) {
3222 /* Basically, load kernel tracer modules */
3223 init_kernel_tracer();
3224 if (kernel_tracer_fd == 0) {
3225 ret = LTTCOMM_KERN_NA;
3226 goto error;
3227 }
3228 }
3229
3230 /* Need a session for kernel command */
3231 if (need_tracing_session) {
3232 if (cmd_ctx->session->kernel_session == NULL) {
3233 ret = create_kernel_session(cmd_ctx->session);
3234 if (ret < 0) {
3235 ret = LTTCOMM_KERN_SESS_FAIL;
3236 goto error;
3237 }
3238 }
3239
3240 /* Start the kernel consumer daemon */
3241 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3242 if (kconsumer_data.pid == 0 &&
3243 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3244 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3245 ret = start_consumerd(&kconsumer_data);
3246 if (ret < 0) {
3247 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3248 goto error;
3249 }
3250 } else {
3251 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3252 }
3253 }
3254 break;
3255 case LTTNG_DOMAIN_UST:
3256 {
3257 if (need_tracing_session) {
3258 if (cmd_ctx->session->ust_session == NULL) {
3259 ret = create_ust_session(cmd_ctx->session,
3260 &cmd_ctx->lsm->domain);
3261 if (ret != LTTCOMM_OK) {
3262 goto error;
3263 }
3264 }
3265 /* Start the UST consumer daemons */
3266 /* 64-bit */
3267 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3268 if (consumerd64_path[0] != '\0' &&
3269 ustconsumer64_data.pid == 0 &&
3270 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3271 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3272 ret = start_consumerd(&ustconsumer64_data);
3273 if (ret < 0) {
3274 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3275 ust_consumerd64_fd = -EINVAL;
3276 goto error;
3277 }
3278
3279 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3280 } else {
3281 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3282 }
3283 /* 32-bit */
3284 if (consumerd32_path[0] != '\0' &&
3285 ustconsumer32_data.pid == 0 &&
3286 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3287 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3288 ret = start_consumerd(&ustconsumer32_data);
3289 if (ret < 0) {
3290 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3291 ust_consumerd32_fd = -EINVAL;
3292 goto error;
3293 }
3294 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3295 } else {
3296 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3297 }
3298 }
3299 break;
3300 }
3301 default:
3302 break;
3303 }
3304
3305 /* Process by command type */
3306 switch (cmd_ctx->lsm->cmd_type) {
3307 case LTTNG_ADD_CONTEXT:
3308 {
3309 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3310 cmd_ctx->lsm->u.context.channel_name,
3311 cmd_ctx->lsm->u.context.event_name,
3312 &cmd_ctx->lsm->u.context.ctx);
3313 break;
3314 }
3315 case LTTNG_DISABLE_CHANNEL:
3316 {
3317 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3318 cmd_ctx->lsm->u.disable.channel_name);
3319 break;
3320 }
3321 case LTTNG_DISABLE_EVENT:
3322 {
3323 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3324 cmd_ctx->lsm->u.disable.channel_name,
3325 cmd_ctx->lsm->u.disable.name);
3326 ret = LTTCOMM_OK;
3327 break;
3328 }
3329 case LTTNG_DISABLE_ALL_EVENT:
3330 {
3331 DBG("Disabling all events");
3332
3333 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3334 cmd_ctx->lsm->u.disable.channel_name);
3335 break;
3336 }
3337 case LTTNG_ENABLE_CHANNEL:
3338 {
3339 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3340 &cmd_ctx->lsm->u.channel.chan);
3341 break;
3342 }
3343 case LTTNG_ENABLE_EVENT:
3344 {
3345 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3346 cmd_ctx->lsm->u.enable.channel_name,
3347 &cmd_ctx->lsm->u.enable.event);
3348 break;
3349 }
3350 case LTTNG_ENABLE_ALL_EVENT:
3351 {
3352 DBG("Enabling all events");
3353
3354 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3355 cmd_ctx->lsm->u.enable.channel_name,
3356 cmd_ctx->lsm->u.enable.event.type);
3357 break;
3358 }
3359 case LTTNG_LIST_TRACEPOINTS:
3360 {
3361 struct lttng_event *events;
3362 ssize_t nb_events;
3363
3364 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3365 if (nb_events < 0) {
3366 ret = -nb_events;
3367 goto error;
3368 }
3369
3370 /*
3371 * Setup lttng message with payload size set to the event list size in
3372 * bytes and then copy list into the llm payload.
3373 */
3374 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3375 if (ret < 0) {
3376 free(events);
3377 goto setup_error;
3378 }
3379
3380 /* Copy event list into message payload */
3381 memcpy(cmd_ctx->llm->payload, events,
3382 sizeof(struct lttng_event) * nb_events);
3383
3384 free(events);
3385
3386 ret = LTTCOMM_OK;
3387 break;
3388 }
3389 case LTTNG_START_TRACE:
3390 {
3391 ret = cmd_start_trace(cmd_ctx->session);
3392 break;
3393 }
3394 case LTTNG_STOP_TRACE:
3395 {
3396 ret = cmd_stop_trace(cmd_ctx->session);
3397 break;
3398 }
3399 case LTTNG_CREATE_SESSION:
3400 {
3401 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3402 cmd_ctx->lsm->session.path);
3403 break;
3404 }
3405 case LTTNG_DESTROY_SESSION:
3406 {
3407 ret = cmd_destroy_session(cmd_ctx->session,
3408 cmd_ctx->lsm->session.name);
3409 break;
3410 }
3411 case LTTNG_LIST_DOMAINS:
3412 {
3413 ssize_t nb_dom;
3414 struct lttng_domain *domains;
3415
3416 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3417 if (nb_dom < 0) {
3418 ret = -nb_dom;
3419 goto error;
3420 }
3421
3422 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3423 if (ret < 0) {
3424 goto setup_error;
3425 }
3426
3427 /* Copy event list into message payload */
3428 memcpy(cmd_ctx->llm->payload, domains,
3429 nb_dom * sizeof(struct lttng_domain));
3430
3431 free(domains);
3432
3433 ret = LTTCOMM_OK;
3434 break;
3435 }
3436 case LTTNG_LIST_CHANNELS:
3437 {
3438 size_t nb_chan;
3439 struct lttng_channel *channels;
3440
3441 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
3442 cmd_ctx->session, &channels);
3443 if (nb_chan < 0) {
3444 ret = -nb_chan;
3445 goto error;
3446 }
3447
3448 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3449 if (ret < 0) {
3450 goto setup_error;
3451 }
3452
3453 /* Copy event list into message payload */
3454 memcpy(cmd_ctx->llm->payload, channels,
3455 nb_chan * sizeof(struct lttng_channel));
3456
3457 free(channels);
3458
3459 ret = LTTCOMM_OK;
3460 break;
3461 }
3462 case LTTNG_LIST_EVENTS:
3463 {
3464 ssize_t nb_event;
3465 struct lttng_event *events = NULL;
3466
3467 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
3468 cmd_ctx->lsm->u.list.channel_name, &events);
3469 if (nb_event < 0) {
3470 ret = -nb_event;
3471 goto error;
3472 }
3473
3474 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3475 if (ret < 0) {
3476 goto setup_error;
3477 }
3478
3479 /* Copy event list into message payload */
3480 memcpy(cmd_ctx->llm->payload, events,
3481 nb_event * sizeof(struct lttng_event));
3482
3483 free(events);
3484
3485 ret = LTTCOMM_OK;
3486 break;
3487 }
3488 case LTTNG_LIST_SESSIONS:
3489 {
3490 session_lock_list();
3491
3492 if (session_list_ptr->count == 0) {
3493 ret = LTTCOMM_NO_SESSION;
3494 session_unlock_list();
3495 goto error;
3496 }
3497
3498 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) *
3499 session_list_ptr->count);
3500 if (ret < 0) {
3501 session_unlock_list();
3502 goto setup_error;
3503 }
3504
3505 /* Filled the session array */
3506 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload));
3507
3508 session_unlock_list();
3509
3510 ret = LTTCOMM_OK;
3511 break;
3512 }
3513 case LTTNG_CALIBRATE:
3514 {
3515 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3516 &cmd_ctx->lsm->u.calibrate);
3517 break;
3518 }
3519 case LTTNG_REGISTER_CONSUMER:
3520 {
3521 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3522 cmd_ctx->lsm->u.reg.path);
3523 break;
3524 }
3525 default:
3526 ret = LTTCOMM_UND;
3527 break;
3528 }
3529
3530 error:
3531 if (cmd_ctx->llm == NULL) {
3532 DBG("Missing llm structure. Allocating one.");
3533 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3534 goto setup_error;
3535 }
3536 }
3537 /* Set return code */
3538 cmd_ctx->llm->ret_code = ret;
3539 setup_error:
3540 if (cmd_ctx->session) {
3541 session_unlock(cmd_ctx->session);
3542 }
3543 init_setup_error:
3544 return ret;
3545 }
3546
3547 /*
3548 * This thread manage all clients request using the unix client socket for
3549 * communication.
3550 */
3551 static void *thread_manage_clients(void *data)
3552 {
3553 int sock = 0, ret, i, pollfd;
3554 uint32_t revents, nb_fd;
3555 struct command_ctx *cmd_ctx = NULL;
3556 struct lttng_poll_event events;
3557
3558 DBG("[thread] Manage client started");
3559
3560 rcu_register_thread();
3561
3562 ret = lttcomm_listen_unix_sock(client_sock);
3563 if (ret < 0) {
3564 goto error;
3565 }
3566
3567 /*
3568 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3569 * more will be added to this poll set.
3570 */
3571 ret = create_thread_poll_set(&events, 2);
3572 if (ret < 0) {
3573 goto error;
3574 }
3575
3576 /* Add the application registration socket */
3577 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3578 if (ret < 0) {
3579 goto error;
3580 }
3581
3582 /*
3583 * Notify parent pid that we are ready to accept command for client side.
3584 */
3585 if (opt_sig_parent) {
3586 kill(ppid, SIGCHLD);
3587 }
3588
3589 while (1) {
3590 DBG("Accepting client command ...");
3591
3592 nb_fd = LTTNG_POLL_GETNB(&events);
3593
3594 /* Inifinite blocking call, waiting for transmission */
3595 ret = lttng_poll_wait(&events, -1);
3596 if (ret < 0) {
3597 goto error;
3598 }
3599
3600 for (i = 0; i < nb_fd; i++) {
3601 /* Fetch once the poll data */
3602 revents = LTTNG_POLL_GETEV(&events, i);
3603 pollfd = LTTNG_POLL_GETFD(&events, i);
3604
3605 /* Thread quit pipe has been closed. Killing thread. */
3606 ret = check_thread_quit_pipe(pollfd, revents);
3607 if (ret) {
3608 goto error;
3609 }
3610
3611 /* Event on the registration socket */
3612 if (pollfd == client_sock) {
3613 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3614 ERR("Client socket poll error");
3615 goto error;
3616 }
3617 }
3618 }
3619
3620 DBG("Wait for client response");
3621
3622 sock = lttcomm_accept_unix_sock(client_sock);
3623 if (sock < 0) {
3624 goto error;
3625 }
3626
3627 /* Allocate context command to process the client request */
3628 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3629 if (cmd_ctx == NULL) {
3630 perror("zmalloc cmd_ctx");
3631 goto error;
3632 }
3633
3634 /* Allocate data buffer for reception */
3635 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3636 if (cmd_ctx->lsm == NULL) {
3637 perror("zmalloc cmd_ctx->lsm");
3638 goto error;
3639 }
3640
3641 cmd_ctx->llm = NULL;
3642 cmd_ctx->session = NULL;
3643
3644 /*
3645 * Data is received from the lttng client. The struct
3646 * lttcomm_session_msg (lsm) contains the command and data request of
3647 * the client.
3648 */
3649 DBG("Receiving data from client ...");
3650 ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm,
3651 sizeof(struct lttcomm_session_msg));
3652 if (ret <= 0) {
3653 DBG("Nothing recv() from client... continuing");
3654 close(sock);
3655 free(cmd_ctx);
3656 continue;
3657 }
3658
3659 // TODO: Validate cmd_ctx including sanity check for
3660 // security purpose.
3661
3662 rcu_thread_online();
3663 /*
3664 * This function dispatch the work to the kernel or userspace tracer
3665 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3666 * informations for the client. The command context struct contains
3667 * everything this function may needs.
3668 */
3669 ret = process_client_msg(cmd_ctx);
3670 rcu_thread_offline();
3671 if (ret < 0) {
3672 /*
3673 * TODO: Inform client somehow of the fatal error. At
3674 * this point, ret < 0 means that a zmalloc failed
3675 * (ENOMEM). Error detected but still accept command.
3676 */
3677 clean_command_ctx(&cmd_ctx);
3678 continue;
3679 }
3680
3681 DBG("Sending response (size: %d, retcode: %s)",
3682 cmd_ctx->lttng_msg_size,
3683 lttng_strerror(-cmd_ctx->llm->ret_code));
3684 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3685 if (ret < 0) {
3686 ERR("Failed to send data back to client");
3687 }
3688
3689 clean_command_ctx(&cmd_ctx);
3690
3691 /* End of transmission */
3692 close(sock);
3693 }
3694
3695 error:
3696 DBG("Client thread dying");
3697 unlink(client_unix_sock_path);
3698 close(client_sock);
3699 close(sock);
3700
3701 lttng_poll_clean(&events);
3702 clean_command_ctx(&cmd_ctx);
3703
3704 rcu_unregister_thread();
3705 return NULL;
3706 }
3707
3708
3709 /*
3710 * usage function on stderr
3711 */
3712 static void usage(void)
3713 {
3714 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3715 fprintf(stderr, " -h, --help Display this usage.\n");
3716 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3717 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3718 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3719 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3720 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
3721 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
3722 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
3723 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
3724 fprintf(stderr, " --consumerd32-path PATH Specify path for the 32-bit UST consumer daemon binary\n");
3725 fprintf(stderr, " --consumerd32-libdir PATH Specify path for the 32-bit UST consumer daemon libraries\n");
3726 fprintf(stderr, " --consumerd64-path PATH Specify path for the 64-bit UST consumer daemon binary\n");
3727 fprintf(stderr, " --consumerd64-libdir PATH Specify path for the 64-bit UST consumer daemon libraries\n");
3728 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3729 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3730 fprintf(stderr, " -V, --version Show version number.\n");
3731 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3732 fprintf(stderr, " -q, --quiet No output at all.\n");
3733 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3734 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3735 }
3736
3737 /*
3738 * daemon argument parsing
3739 */
3740 static int parse_args(int argc, char **argv)
3741 {
3742 int c;
3743
3744 static struct option long_options[] = {
3745 { "client-sock", 1, 0, 'c' },
3746 { "apps-sock", 1, 0, 'a' },
3747 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3748 { "kconsumerd-err-sock", 1, 0, 'E' },
3749 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
3750 { "ustconsumerd32-err-sock", 1, 0, 'H' },
3751 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
3752 { "ustconsumerd64-err-sock", 1, 0, 'F' },
3753 { "consumerd32-path", 1, 0, 'u' },
3754 { "consumerd32-libdir", 1, 0, 'U' },
3755 { "consumerd64-path", 1, 0, 't' },
3756 { "consumerd64-libdir", 1, 0, 'T' },
3757 { "daemonize", 0, 0, 'd' },
3758 { "sig-parent", 0, 0, 'S' },
3759 { "help", 0, 0, 'h' },
3760 { "group", 1, 0, 'g' },
3761 { "version", 0, 0, 'V' },
3762 { "quiet", 0, 0, 'q' },
3763 { "verbose", 0, 0, 'v' },
3764 { "verbose-consumer", 0, 0, 'Z' },
3765 { NULL, 0, 0, 0 }
3766 };
3767
3768 while (1) {
3769 int option_index = 0;
3770 c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:C:E:D:F:Z:u:t",
3771 long_options, &option_index);
3772 if (c == -1) {
3773 break;
3774 }
3775
3776 switch (c) {
3777 case 0:
3778 fprintf(stderr, "option %s", long_options[option_index].name);
3779 if (optarg) {
3780 fprintf(stderr, " with arg %s\n", optarg);
3781 }
3782 break;
3783 case 'c':
3784 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3785 break;
3786 case 'a':
3787 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3788 break;
3789 case 'd':
3790 opt_daemon = 1;
3791 break;
3792 case 'g':
3793 opt_tracing_group = optarg;
3794 break;
3795 case 'h':
3796 usage();
3797 exit(EXIT_FAILURE);
3798 case 'V':
3799 fprintf(stdout, "%s\n", VERSION);
3800 exit(EXIT_SUCCESS);
3801 case 'S':
3802 opt_sig_parent = 1;
3803 break;
3804 case 'E':
3805 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3806 break;
3807 case 'C':
3808 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3809 break;
3810 case 'F':
3811 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3812 break;
3813 case 'D':
3814 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3815 break;
3816 case 'H':
3817 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3818 break;
3819 case 'G':
3820 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3821 break;
3822 case 'q':
3823 opt_quiet = 1;
3824 break;
3825 case 'v':
3826 /* Verbose level can increase using multiple -v */
3827 opt_verbose += 1;
3828 break;
3829 case 'Z':
3830 opt_verbose_consumer += 1;
3831 break;
3832 case 'u':
3833 consumerd32_path= optarg;
3834 break;
3835 case 'U':
3836 consumerd32_libdir = optarg;
3837 break;
3838 case 't':
3839 consumerd64_path = optarg;
3840 break;
3841 case 'T':
3842 consumerd64_libdir = optarg;
3843 break;
3844 default:
3845 /* Unknown option or other error.
3846 * Error is printed by getopt, just return */
3847 return -1;
3848 }
3849 }
3850
3851 return 0;
3852 }
3853
3854 /*
3855 * Creates the two needed socket by the daemon.
3856 * apps_sock - The communication socket for all UST apps.
3857 * client_sock - The communication of the cli tool (lttng).
3858 */
3859 static int init_daemon_socket(void)
3860 {
3861 int ret = 0;
3862 mode_t old_umask;
3863
3864 old_umask = umask(0);
3865
3866 /* Create client tool unix socket */
3867 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
3868 if (client_sock < 0) {
3869 ERR("Create unix sock failed: %s", client_unix_sock_path);
3870 ret = -1;
3871 goto end;
3872 }
3873
3874 /* File permission MUST be 660 */
3875 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
3876 if (ret < 0) {
3877 ERR("Set file permissions failed: %s", client_unix_sock_path);
3878 perror("chmod");
3879 goto end;
3880 }
3881
3882 /* Create the application unix socket */
3883 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
3884 if (apps_sock < 0) {
3885 ERR("Create unix sock failed: %s", apps_unix_sock_path);
3886 ret = -1;
3887 goto end;
3888 }
3889
3890 /* File permission MUST be 666 */
3891 ret = chmod(apps_unix_sock_path,
3892 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
3893 if (ret < 0) {
3894 ERR("Set file permissions failed: %s", apps_unix_sock_path);
3895 perror("chmod");
3896 goto end;
3897 }
3898
3899 end:
3900 umask(old_umask);
3901 return ret;
3902 }
3903
3904 /*
3905 * Check if the global socket is available, and if a daemon is answering at the
3906 * other side. If yes, error is returned.
3907 */
3908 static int check_existing_daemon(void)
3909 {
3910 if (access(client_unix_sock_path, F_OK) < 0 &&
3911 access(apps_unix_sock_path, F_OK) < 0) {
3912 return 0;
3913 }
3914
3915 /* Is there anybody out there ? */
3916 if (lttng_session_daemon_alive()) {
3917 return -EEXIST;
3918 } else {
3919 return 0;
3920 }
3921 }
3922
3923 /*
3924 * Set the tracing group gid onto the client socket.
3925 *
3926 * Race window between mkdir and chown is OK because we are going from more
3927 * permissive (root.root) to les permissive (root.tracing).
3928 */
3929 static int set_permissions(void)
3930 {
3931 int ret;
3932 gid_t gid;
3933
3934 gid = allowed_group();
3935 if (gid < 0) {
3936 if (is_root) {
3937 WARN("No tracing group detected");
3938 ret = 0;
3939 } else {
3940 ERR("Missing tracing group. Aborting execution.");
3941 ret = -1;
3942 }
3943 goto end;
3944 }
3945
3946 /* Set lttng run dir */
3947 ret = chown(LTTNG_RUNDIR, 0, gid);
3948 if (ret < 0) {
3949 ERR("Unable to set group on " LTTNG_RUNDIR);
3950 perror("chown");
3951 }
3952
3953 /* lttng client socket path */
3954 ret = chown(client_unix_sock_path, 0, gid);
3955 if (ret < 0) {
3956 ERR("Unable to set group on %s", client_unix_sock_path);
3957 perror("chown");
3958 }
3959
3960 /* kconsumer error socket path */
3961 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
3962 if (ret < 0) {
3963 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
3964 perror("chown");
3965 }
3966
3967 /* 64-bit ustconsumer error socket path */
3968 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
3969 if (ret < 0) {
3970 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
3971 perror("chown");
3972 }
3973
3974 /* 32-bit ustconsumer compat32 error socket path */
3975 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
3976 if (ret < 0) {
3977 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
3978 perror("chown");
3979 }
3980
3981 DBG("All permissions are set");
3982
3983 end:
3984 return ret;
3985 }
3986
3987 /*
3988 * Create the pipe used to wake up the kernel thread.
3989 */
3990 static int create_kernel_poll_pipe(void)
3991 {
3992 return pipe2(kernel_poll_pipe, O_CLOEXEC);
3993 }
3994
3995 /*
3996 * Create the application command pipe to wake thread_manage_apps.
3997 */
3998 static int create_apps_cmd_pipe(void)
3999 {
4000 return pipe2(apps_cmd_pipe, O_CLOEXEC);
4001 }
4002
4003 /*
4004 * Create the lttng run directory needed for all global sockets and pipe.
4005 */
4006 static int create_lttng_rundir(void)
4007 {
4008 int ret;
4009
4010 ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG );
4011 if (ret < 0) {
4012 if (errno != EEXIST) {
4013 ERR("Unable to create " LTTNG_RUNDIR);
4014 goto error;
4015 } else {
4016 ret = 0;
4017 }
4018 }
4019
4020 error:
4021 return ret;
4022 }
4023
4024 /*
4025 * Setup sockets and directory needed by the kconsumerd communication with the
4026 * session daemon.
4027 */
4028 static int set_consumer_sockets(struct consumer_data *consumer_data)
4029 {
4030 int ret;
4031 const char *path;
4032
4033 switch (consumer_data->type) {
4034 case LTTNG_CONSUMER_KERNEL:
4035 path = KCONSUMERD_PATH;
4036 break;
4037 case LTTNG_CONSUMER64_UST:
4038 path = USTCONSUMERD64_PATH;
4039 break;
4040 case LTTNG_CONSUMER32_UST:
4041 path = USTCONSUMERD32_PATH;
4042 break;
4043 default:
4044 ERR("Consumer type unknown");
4045 ret = -EINVAL;
4046 goto error;
4047 }
4048
4049 ret = mkdir(path, S_IRWXU | S_IRWXG);
4050 if (ret < 0) {
4051 if (errno != EEXIST) {
4052 ERR("Failed to create %s", path);
4053 goto error;
4054 }
4055 ret = 0;
4056 }
4057
4058 /* Create the kconsumerd error unix socket */
4059 consumer_data->err_sock =
4060 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
4061 if (consumer_data->err_sock < 0) {
4062 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
4063 ret = -1;
4064 goto error;
4065 }
4066
4067 /* File permission MUST be 660 */
4068 ret = chmod(consumer_data->err_unix_sock_path,
4069 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
4070 if (ret < 0) {
4071 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
4072 perror("chmod");
4073 goto error;
4074 }
4075
4076 error:
4077 return ret;
4078 }
4079
4080 /*
4081 * Signal handler for the daemon
4082 *
4083 * Simply stop all worker threads, leaving main() return gracefully after
4084 * joining all threads and calling cleanup().
4085 */
4086 static void sighandler(int sig)
4087 {
4088 switch (sig) {
4089 case SIGPIPE:
4090 DBG("SIGPIPE catched");
4091 return;
4092 case SIGINT:
4093 DBG("SIGINT catched");
4094 stop_threads();
4095 break;
4096 case SIGTERM:
4097 DBG("SIGTERM catched");
4098 stop_threads();
4099 break;
4100 default:
4101 break;
4102 }
4103 }
4104
4105 /*
4106 * Setup signal handler for :
4107 * SIGINT, SIGTERM, SIGPIPE
4108 */
4109 static int set_signal_handler(void)
4110 {
4111 int ret = 0;
4112 struct sigaction sa;
4113 sigset_t sigset;
4114
4115 if ((ret = sigemptyset(&sigset)) < 0) {
4116 perror("sigemptyset");
4117 return ret;
4118 }
4119
4120 sa.sa_handler = sighandler;
4121 sa.sa_mask = sigset;
4122 sa.sa_flags = 0;
4123 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
4124 perror("sigaction");
4125 return ret;
4126 }
4127
4128 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
4129 perror("sigaction");
4130 return ret;
4131 }
4132
4133 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
4134 perror("sigaction");
4135 return ret;
4136 }
4137
4138 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
4139
4140 return ret;
4141 }
4142
4143 /*
4144 * Set open files limit to unlimited. This daemon can open a large number of
4145 * file descriptors in order to consumer multiple kernel traces.
4146 */
4147 static void set_ulimit(void)
4148 {
4149 int ret;
4150 struct rlimit lim;
4151
4152 /* The kernel does not allowed an infinite limit for open files */
4153 lim.rlim_cur = 65535;
4154 lim.rlim_max = 65535;
4155
4156 ret = setrlimit(RLIMIT_NOFILE, &lim);
4157 if (ret < 0) {
4158 perror("failed to set open files limit");
4159 }
4160 }
4161
4162 /*
4163 * main
4164 */
4165 int main(int argc, char **argv)
4166 {
4167 int ret = 0;
4168 void *status;
4169 const char *home_path;
4170
4171 rcu_register_thread();
4172
4173 /* Create thread quit pipe */
4174 if ((ret = init_thread_quit_pipe()) < 0) {
4175 goto error;
4176 }
4177
4178 setup_consumerd_path();
4179
4180 /* Parse arguments */
4181 progname = argv[0];
4182 if ((ret = parse_args(argc, argv) < 0)) {
4183 goto error;
4184 }
4185
4186 /* Daemonize */
4187 if (opt_daemon) {
4188 ret = daemon(0, 0);
4189 if (ret < 0) {
4190 perror("daemon");
4191 goto error;
4192 }
4193 }
4194
4195 /* Check if daemon is UID = 0 */
4196 is_root = !getuid();
4197
4198 if (is_root) {
4199 ret = create_lttng_rundir();
4200 if (ret < 0) {
4201 goto error;
4202 }
4203
4204 if (strlen(apps_unix_sock_path) == 0) {
4205 snprintf(apps_unix_sock_path, PATH_MAX,
4206 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
4207 }
4208
4209 if (strlen(client_unix_sock_path) == 0) {
4210 snprintf(client_unix_sock_path, PATH_MAX,
4211 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
4212 }
4213
4214 /* Set global SHM for ust */
4215 if (strlen(wait_shm_path) == 0) {
4216 snprintf(wait_shm_path, PATH_MAX,
4217 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
4218 }
4219 } else {
4220 home_path = get_home_dir();
4221 if (home_path == NULL) {
4222 /* TODO: Add --socket PATH option */
4223 ERR("Can't get HOME directory for sockets creation.");
4224 ret = -EPERM;
4225 goto error;
4226 }
4227
4228 if (strlen(apps_unix_sock_path) == 0) {
4229 snprintf(apps_unix_sock_path, PATH_MAX,
4230 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
4231 }
4232
4233 /* Set the cli tool unix socket path */
4234 if (strlen(client_unix_sock_path) == 0) {
4235 snprintf(client_unix_sock_path, PATH_MAX,
4236 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
4237 }
4238
4239 /* Set global SHM for ust */
4240 if (strlen(wait_shm_path) == 0) {
4241 snprintf(wait_shm_path, PATH_MAX,
4242 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
4243 }
4244 }
4245
4246 DBG("Client socket path %s", client_unix_sock_path);
4247 DBG("Application socket path %s", apps_unix_sock_path);
4248
4249 /*
4250 * See if daemon already exist.
4251 */
4252 if ((ret = check_existing_daemon()) < 0) {
4253 ERR("Already running daemon.\n");
4254 /*
4255 * We do not goto exit because we must not cleanup()
4256 * because a daemon is already running.
4257 */
4258 goto error;
4259 }
4260
4261 /* After this point, we can safely call cleanup() with "goto exit" */
4262
4263 /*
4264 * These actions must be executed as root. We do that *after* setting up
4265 * the sockets path because we MUST make the check for another daemon using
4266 * those paths *before* trying to set the kernel consumer sockets and init
4267 * kernel tracer.
4268 */
4269 if (is_root) {
4270 ret = set_consumer_sockets(&kconsumer_data);
4271 if (ret < 0) {
4272 goto exit;
4273 }
4274
4275 ret = set_consumer_sockets(&ustconsumer64_data);
4276 if (ret < 0) {
4277 goto exit;
4278 }
4279
4280 ret = set_consumer_sockets(&ustconsumer32_data);
4281 if (ret < 0) {
4282 goto exit;
4283 }
4284
4285 /* Setup kernel tracer */
4286 init_kernel_tracer();
4287
4288 /* Set ulimit for open files */
4289 set_ulimit();
4290 }
4291
4292 if ((ret = set_signal_handler()) < 0) {
4293 goto exit;
4294 }
4295
4296 /* Setup the needed unix socket */
4297 if ((ret = init_daemon_socket()) < 0) {
4298 goto exit;
4299 }
4300
4301 /* Set credentials to socket */
4302 if (is_root && ((ret = set_permissions()) < 0)) {
4303 goto exit;
4304 }
4305
4306 /* Get parent pid if -S, --sig-parent is specified. */
4307 if (opt_sig_parent) {
4308 ppid = getppid();
4309 }
4310
4311 /* Setup the kernel pipe for waking up the kernel thread */
4312 if ((ret = create_kernel_poll_pipe()) < 0) {
4313 goto exit;
4314 }
4315
4316 /* Setup the thread apps communication pipe. */
4317 if ((ret = create_apps_cmd_pipe()) < 0) {
4318 goto exit;
4319 }
4320
4321 /* Init UST command queue. */
4322 cds_wfq_init(&ust_cmd_queue.queue);
4323
4324 /* Init UST app hash table */
4325 ust_app_ht_alloc();
4326
4327 /*
4328 * Get session list pointer. This pointer MUST NOT be free(). This list is
4329 * statically declared in session.c
4330 */
4331 session_list_ptr = session_get_list();
4332
4333 /* Set up max poll set size */
4334 lttng_poll_set_max_size();
4335
4336 /* Create thread to manage the client socket */
4337 ret = pthread_create(&client_thread, NULL,
4338 thread_manage_clients, (void *) NULL);
4339 if (ret != 0) {
4340 perror("pthread_create clients");
4341 goto exit_client;
4342 }
4343
4344 /* Create thread to dispatch registration */
4345 ret = pthread_create(&dispatch_thread, NULL,
4346 thread_dispatch_ust_registration, (void *) NULL);
4347 if (ret != 0) {
4348 perror("pthread_create dispatch");
4349 goto exit_dispatch;
4350 }
4351
4352 /* Create thread to manage application registration. */
4353 ret = pthread_create(&reg_apps_thread, NULL,
4354 thread_registration_apps, (void *) NULL);
4355 if (ret != 0) {
4356 perror("pthread_create registration");
4357 goto exit_reg_apps;
4358 }
4359
4360 /* Create thread to manage application socket */
4361 ret = pthread_create(&apps_thread, NULL,
4362 thread_manage_apps, (void *) NULL);
4363 if (ret != 0) {
4364 perror("pthread_create apps");
4365 goto exit_apps;
4366 }
4367
4368 /* Create kernel thread to manage kernel event */
4369 ret = pthread_create(&kernel_thread, NULL,
4370 thread_manage_kernel, (void *) NULL);
4371 if (ret != 0) {
4372 perror("pthread_create kernel");
4373 goto exit_kernel;
4374 }
4375
4376 ret = pthread_join(kernel_thread, &status);
4377 if (ret != 0) {
4378 perror("pthread_join");
4379 goto error; /* join error, exit without cleanup */
4380 }
4381
4382 exit_kernel:
4383 ret = pthread_join(apps_thread, &status);
4384 if (ret != 0) {
4385 perror("pthread_join");
4386 goto error; /* join error, exit without cleanup */
4387 }
4388
4389 exit_apps:
4390 ret = pthread_join(reg_apps_thread, &status);
4391 if (ret != 0) {
4392 perror("pthread_join");
4393 goto error; /* join error, exit without cleanup */
4394 }
4395
4396 exit_reg_apps:
4397 ret = pthread_join(dispatch_thread, &status);
4398 if (ret != 0) {
4399 perror("pthread_join");
4400 goto error; /* join error, exit without cleanup */
4401 }
4402
4403 exit_dispatch:
4404 ret = pthread_join(client_thread, &status);
4405 if (ret != 0) {
4406 perror("pthread_join");
4407 goto error; /* join error, exit without cleanup */
4408 }
4409
4410 ret = join_consumer_thread(&kconsumer_data);
4411 if (ret != 0) {
4412 perror("join_consumer");
4413 goto error; /* join error, exit without cleanup */
4414 }
4415
4416 exit_client:
4417 exit:
4418 /*
4419 * cleanup() is called when no other thread is running.
4420 */
4421 rcu_thread_online();
4422 cleanup();
4423 rcu_thread_offline();
4424 rcu_unregister_thread();
4425 if (!ret)
4426 exit(EXIT_SUCCESS);
4427 error:
4428 exit(EXIT_FAILURE);
4429 }
LTTng 2.0 tools and control repository
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