Add missing rcu read lock
[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 }
2077 i++;
2078 }
2079
2080 ret = nb_event;
2081 *events = tmp;
2082
2083 error:
2084 rcu_read_unlock();
2085 return ret;
2086 }
2087
2088 /*
2089 * Fill lttng_event array of all kernel events in the channel.
2090 */
2091 static int list_lttng_kernel_events(char *channel_name,
2092 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2093 {
2094 int i = 0, ret;
2095 unsigned int nb_event;
2096 struct ltt_kernel_event *event;
2097 struct ltt_kernel_channel *kchan;
2098
2099 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2100 if (kchan == NULL) {
2101 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2102 goto error;
2103 }
2104
2105 nb_event = kchan->event_count;
2106
2107 DBG("Listing events for channel %s", kchan->channel->name);
2108
2109 if (nb_event == 0) {
2110 ret = nb_event;
2111 goto error;
2112 }
2113
2114 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2115 if (*events == NULL) {
2116 ret = LTTCOMM_FATAL;
2117 goto error;
2118 }
2119
2120 /* Kernel channels */
2121 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2122 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2123 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2124 (*events)[i].enabled = event->enabled;
2125 switch (event->event->instrumentation) {
2126 case LTTNG_KERNEL_TRACEPOINT:
2127 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2128 break;
2129 case LTTNG_KERNEL_KPROBE:
2130 case LTTNG_KERNEL_KRETPROBE:
2131 (*events)[i].type = LTTNG_EVENT_PROBE;
2132 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2133 sizeof(struct lttng_kernel_kprobe));
2134 break;
2135 case LTTNG_KERNEL_FUNCTION:
2136 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2137 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2138 sizeof(struct lttng_kernel_function));
2139 break;
2140 case LTTNG_KERNEL_NOOP:
2141 (*events)[i].type = LTTNG_EVENT_NOOP;
2142 break;
2143 case LTTNG_KERNEL_SYSCALL:
2144 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2145 break;
2146 case LTTNG_KERNEL_ALL:
2147 assert(0);
2148 break;
2149 }
2150 i++;
2151 }
2152
2153 return nb_event;
2154
2155 error:
2156 return ret;
2157 }
2158
2159 /*
2160 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2161 */
2162 static int cmd_disable_channel(struct ltt_session *session,
2163 int domain, char *channel_name)
2164 {
2165 int ret;
2166 struct ltt_ust_session *usess;
2167
2168 usess = session->ust_session;
2169
2170 switch (domain) {
2171 case LTTNG_DOMAIN_KERNEL:
2172 {
2173 ret = channel_kernel_disable(session->kernel_session,
2174 channel_name);
2175 if (ret != LTTCOMM_OK) {
2176 goto error;
2177 }
2178
2179 kernel_wait_quiescent(kernel_tracer_fd);
2180 break;
2181 }
2182 case LTTNG_DOMAIN_UST:
2183 {
2184 struct ltt_ust_channel *uchan;
2185
2186 /* Get channel in global UST domain HT */
2187 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2188 channel_name);
2189 if (uchan == NULL) {
2190 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2191 goto error;
2192 }
2193
2194 /* Already disabled */
2195 if (!uchan->enabled) {
2196 DBG2("UST channel %s already disabled", channel_name);
2197 break;
2198 }
2199
2200 ret = ust_app_disable_channel_glb(usess, uchan);
2201 if (ret < 0) {
2202 ret = LTTCOMM_UST_DISABLE_FAIL;
2203 goto error;
2204 }
2205
2206 uchan->enabled = 0;
2207
2208 break;
2209 }
2210 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2211 case LTTNG_DOMAIN_UST_EXEC_NAME:
2212 case LTTNG_DOMAIN_UST_PID:
2213 ret = LTTCOMM_NOT_IMPLEMENTED;
2214 goto error;
2215 default:
2216 ret = LTTCOMM_UNKNOWN_DOMAIN;
2217 goto error;
2218 }
2219
2220 ret = LTTCOMM_OK;
2221
2222 error:
2223 return ret;
2224 }
2225
2226 /*
2227 * Copy channel from attributes and set it in the application channel list.
2228 */
2229 /*
2230 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
2231 struct lttng_channel *attr, struct ust_app *app)
2232 {
2233 int ret;
2234 struct ltt_ust_channel *uchan, *new_chan;
2235
2236 uchan = trace_ust_get_channel_by_key(usess->channels, attr->name);
2237 if (uchan == NULL) {
2238 ret = LTTCOMM_FATAL;
2239 goto error;
2240 }
2241
2242 new_chan = trace_ust_create_channel(attr, usess->path);
2243 if (new_chan == NULL) {
2244 PERROR("malloc ltt_ust_channel");
2245 ret = LTTCOMM_FATAL;
2246 goto error;
2247 }
2248
2249 ret = channel_ust_copy(new_chan, uchan);
2250 if (ret < 0) {
2251 ret = LTTCOMM_FATAL;
2252 goto error;
2253 }
2254
2255 error:
2256 return ret;
2257 }
2258 */
2259
2260 /*
2261 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2262 */
2263 static int cmd_enable_channel(struct ltt_session *session,
2264 int domain, struct lttng_channel *attr)
2265 {
2266 int ret;
2267 struct ltt_ust_session *usess = session->ust_session;
2268
2269 DBG("Enabling channel %s for session %s", attr->name, session->name);
2270
2271 switch (domain) {
2272 case LTTNG_DOMAIN_KERNEL:
2273 {
2274 struct ltt_kernel_channel *kchan;
2275
2276 kchan = trace_kernel_get_channel_by_name(attr->name,
2277 session->kernel_session);
2278 if (kchan == NULL) {
2279 ret = channel_kernel_create(session->kernel_session,
2280 attr, kernel_poll_pipe[1]);
2281 } else {
2282 ret = channel_kernel_enable(session->kernel_session, kchan);
2283 }
2284
2285 if (ret != LTTCOMM_OK) {
2286 goto error;
2287 }
2288
2289 kernel_wait_quiescent(kernel_tracer_fd);
2290 break;
2291 }
2292 case LTTNG_DOMAIN_UST:
2293 {
2294 struct ltt_ust_channel *uchan;
2295
2296 DBG2("Enabling channel for LTTNG_DOMAIN_UST");
2297
2298 /* Get channel in global UST domain HT */
2299 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2300 attr->name);
2301 if (uchan == NULL) {
2302 uchan = trace_ust_create_channel(attr, usess->pathname);
2303 if (uchan == NULL) {
2304 ret = LTTCOMM_UST_CHAN_FAIL;
2305 goto error;
2306 }
2307
2308 /* Add channel to all registered applications */
2309 ret = ust_app_create_channel_glb(usess, uchan);
2310 if (ret != 0) {
2311 ret = LTTCOMM_UST_CHAN_FAIL;
2312 goto error;
2313 }
2314
2315 rcu_read_lock();
2316 hashtable_add_unique(usess->domain_global.channels, &uchan->node);
2317 rcu_read_unlock();
2318
2319 DBG2("UST channel %s added to global domain HT", attr->name);
2320 } else {
2321 /* If already enabled, everything is OK */
2322 if (uchan->enabled) {
2323 break;
2324 }
2325
2326 ret = ust_app_enable_channel_glb(usess, uchan);
2327 if (ret < 0) {
2328 if (ret != -EEXIST) {
2329 ret = LTTCOMM_UST_CHAN_ENABLE_FAIL;
2330 goto error;
2331 } else {
2332 ret = LTTCOMM_OK;
2333 }
2334 }
2335 }
2336
2337 uchan->enabled = 1;
2338
2339 break;
2340 }
2341 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2342 case LTTNG_DOMAIN_UST_EXEC_NAME:
2343 case LTTNG_DOMAIN_UST_PID:
2344 ret = LTTCOMM_NOT_IMPLEMENTED;
2345 goto error;
2346 default:
2347 ret = LTTCOMM_UNKNOWN_DOMAIN;
2348 goto error;
2349 }
2350
2351 ret = LTTCOMM_OK;
2352
2353 error:
2354 return ret;
2355 }
2356
2357 /*
2358 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2359 */
2360 static int cmd_disable_event(struct ltt_session *session, int domain,
2361 char *channel_name, char *event_name)
2362 {
2363 int ret;
2364
2365 switch (domain) {
2366 case LTTNG_DOMAIN_KERNEL:
2367 {
2368 struct ltt_kernel_channel *kchan;
2369 struct ltt_kernel_session *ksess;
2370
2371 ksess = session->kernel_session;
2372
2373 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2374 if (kchan == NULL) {
2375 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2376 goto error;
2377 }
2378
2379 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2380 if (ret != LTTCOMM_OK) {
2381 goto error;
2382 }
2383
2384 kernel_wait_quiescent(kernel_tracer_fd);
2385 break;
2386 }
2387 case LTTNG_DOMAIN_UST:
2388 {
2389 struct ltt_ust_session *usess;
2390 struct ltt_ust_channel *uchan;
2391 struct ltt_ust_event *uevent;
2392
2393 usess = session->ust_session;
2394
2395 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2396 channel_name);
2397 if (uchan == NULL) {
2398 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2399 goto error;
2400 }
2401
2402 uevent = trace_ust_find_event_by_name(uchan->events, event_name);
2403 if (uevent == NULL) {
2404 ret = LTTCOMM_UST_EVENT_NOT_FOUND;
2405 goto error;
2406 }
2407
2408 ret = ust_app_disable_event_glb(usess, uchan, uevent);
2409 if (ret < 0) {
2410 ret = LTTCOMM_UST_DISABLE_FAIL;
2411 goto error;
2412 }
2413
2414 uevent->enabled = 0;
2415
2416 DBG2("Disable UST event %s in channel %s completed", event_name,
2417 channel_name);
2418
2419 break;
2420 }
2421 case LTTNG_DOMAIN_UST_EXEC_NAME:
2422 case LTTNG_DOMAIN_UST_PID:
2423 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2424 default:
2425 ret = LTTCOMM_NOT_IMPLEMENTED;
2426 goto error;
2427 }
2428
2429 ret = LTTCOMM_OK;
2430
2431 error:
2432 return ret;
2433 }
2434
2435 /*
2436 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2437 */
2438 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2439 char *channel_name)
2440 {
2441 int ret;
2442
2443 switch (domain) {
2444 case LTTNG_DOMAIN_KERNEL:
2445 {
2446 struct ltt_kernel_session *ksess;
2447 struct ltt_kernel_channel *kchan;
2448
2449 ksess = session->kernel_session;
2450
2451 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2452 if (kchan == NULL) {
2453 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2454 goto error;
2455 }
2456
2457 ret = event_kernel_disable_all(ksess, kchan);
2458 if (ret != LTTCOMM_OK) {
2459 goto error;
2460 }
2461
2462 kernel_wait_quiescent(kernel_tracer_fd);
2463 break;
2464 }
2465 case LTTNG_DOMAIN_UST:
2466 {
2467 struct ltt_ust_session *usess;
2468 struct ltt_ust_channel *uchan;
2469
2470 usess = session->ust_session;
2471
2472 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2473 channel_name);
2474 if (uchan == NULL) {
2475 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2476 goto error;
2477 }
2478
2479 ret = ust_app_disable_all_event_glb(usess, uchan);
2480 if (ret < 0) {
2481 ret = LTTCOMM_UST_DISABLE_FAIL;
2482 goto error;
2483 }
2484
2485 DBG2("Disable all UST event in channel %s completed", channel_name);
2486
2487 break;
2488 }
2489 case LTTNG_DOMAIN_UST_EXEC_NAME:
2490 case LTTNG_DOMAIN_UST_PID:
2491 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2492 default:
2493 ret = LTTCOMM_NOT_IMPLEMENTED;
2494 goto error;
2495 }
2496
2497 ret = LTTCOMM_OK;
2498
2499 error:
2500 return ret;
2501 }
2502
2503 /*
2504 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2505 */
2506 static int cmd_add_context(struct ltt_session *session, int domain,
2507 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2508 {
2509 int ret;
2510
2511 switch (domain) {
2512 case LTTNG_DOMAIN_KERNEL:
2513 /* Add kernel context to kernel tracer */
2514 ret = context_kernel_add(session->kernel_session, ctx,
2515 event_name, channel_name);
2516 if (ret != LTTCOMM_OK) {
2517 goto error;
2518 }
2519 break;
2520 case LTTNG_DOMAIN_UST:
2521 {
2522 struct ltt_ust_session *usess = session->ust_session;
2523
2524 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2525 if (ret != LTTCOMM_OK) {
2526 goto error;
2527 }
2528 break;
2529 }
2530 case LTTNG_DOMAIN_UST_EXEC_NAME:
2531 case LTTNG_DOMAIN_UST_PID:
2532 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2533 default:
2534 ret = LTTCOMM_NOT_IMPLEMENTED;
2535 goto error;
2536 }
2537
2538 ret = LTTCOMM_OK;
2539
2540 error:
2541 return ret;
2542 }
2543
2544 /*
2545 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2546 */
2547 static int cmd_enable_event(struct ltt_session *session, int domain,
2548 char *channel_name, struct lttng_event *event)
2549 {
2550 int ret;
2551 struct lttng_channel *attr;
2552 struct ltt_ust_session *usess = session->ust_session;
2553
2554 switch (domain) {
2555 case LTTNG_DOMAIN_KERNEL:
2556 {
2557 struct ltt_kernel_channel *kchan;
2558
2559 kchan = trace_kernel_get_channel_by_name(channel_name,
2560 session->kernel_session);
2561 if (kchan == NULL) {
2562 attr = channel_new_default_attr(domain);
2563 if (attr == NULL) {
2564 ret = LTTCOMM_FATAL;
2565 goto error;
2566 }
2567 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2568
2569 /* This call will notify the kernel thread */
2570 ret = channel_kernel_create(session->kernel_session,
2571 attr, kernel_poll_pipe[1]);
2572 if (ret != LTTCOMM_OK) {
2573 free(attr);
2574 goto error;
2575 }
2576 free(attr);
2577 }
2578
2579 /* Get the newly created kernel channel pointer */
2580 kchan = trace_kernel_get_channel_by_name(channel_name,
2581 session->kernel_session);
2582 if (kchan == NULL) {
2583 /* This sould not happen... */
2584 ret = LTTCOMM_FATAL;
2585 goto error;
2586 }
2587
2588 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2589 event);
2590 if (ret != LTTCOMM_OK) {
2591 goto error;
2592 }
2593
2594 kernel_wait_quiescent(kernel_tracer_fd);
2595 break;
2596 }
2597 case LTTNG_DOMAIN_UST:
2598 {
2599 struct lttng_channel *attr;
2600 struct ltt_ust_channel *uchan;
2601
2602 /* Get channel from global UST domain */
2603 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2604 channel_name);
2605 if (uchan == NULL) {
2606 /* Create default channel */
2607 attr = channel_new_default_attr(domain);
2608 if (attr == NULL) {
2609 ret = LTTCOMM_FATAL;
2610 goto error;
2611 }
2612 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2613 attr->name[NAME_MAX - 1] = '\0';
2614
2615 /* Use the internal command enable channel */
2616 ret = cmd_enable_channel(session, domain, attr);
2617 if (ret != LTTCOMM_OK) {
2618 free(attr);
2619 goto error;
2620 }
2621 free(attr);
2622
2623 /* Get the newly created channel reference back */
2624 uchan = trace_ust_find_channel_by_name(
2625 usess->domain_global.channels, channel_name);
2626 if (uchan == NULL) {
2627 /* Something is really wrong */
2628 ret = LTTCOMM_FATAL;
2629 goto error;
2630 }
2631 }
2632
2633 /* At this point, the session and channel exist on the tracer */
2634
2635 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2636 if (ret != LTTCOMM_OK) {
2637 goto error;
2638 }
2639 break;
2640 }
2641 case LTTNG_DOMAIN_UST_EXEC_NAME:
2642 case LTTNG_DOMAIN_UST_PID:
2643 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2644 default:
2645 ret = LTTCOMM_NOT_IMPLEMENTED;
2646 goto error;
2647 }
2648
2649 ret = LTTCOMM_OK;
2650
2651 error:
2652 return ret;
2653 }
2654
2655 /*
2656 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2657 */
2658 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2659 char *channel_name, int event_type)
2660 {
2661 int ret;
2662 struct ltt_kernel_channel *kchan;
2663
2664 switch (domain) {
2665 case LTTNG_DOMAIN_KERNEL:
2666 kchan = trace_kernel_get_channel_by_name(channel_name,
2667 session->kernel_session);
2668 if (kchan == NULL) {
2669 /* This call will notify the kernel thread */
2670 ret = channel_kernel_create(session->kernel_session, NULL,
2671 kernel_poll_pipe[1]);
2672 if (ret != LTTCOMM_OK) {
2673 goto error;
2674 }
2675 }
2676
2677 /* Get the newly created kernel channel pointer */
2678 kchan = trace_kernel_get_channel_by_name(channel_name,
2679 session->kernel_session);
2680 if (kchan == NULL) {
2681 /* This sould not happen... */
2682 ret = LTTCOMM_FATAL;
2683 goto error;
2684 }
2685
2686 switch (event_type) {
2687 case LTTNG_KERNEL_SYSCALL:
2688 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2689 kchan, kernel_tracer_fd);
2690 break;
2691 case LTTNG_KERNEL_TRACEPOINT:
2692 /*
2693 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2694 * events already registered to the channel.
2695 */
2696 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2697 kchan, kernel_tracer_fd);
2698 break;
2699 case LTTNG_KERNEL_ALL:
2700 /* Enable syscalls and tracepoints */
2701 ret = event_kernel_enable_all(session->kernel_session,
2702 kchan, kernel_tracer_fd);
2703 break;
2704 default:
2705 ret = LTTCOMM_KERN_ENABLE_FAIL;
2706 goto error;
2707 }
2708 if (ret != LTTCOMM_OK) {
2709 goto error;
2710 }
2711
2712 kernel_wait_quiescent(kernel_tracer_fd);
2713 break;
2714 default:
2715 /* TODO: Userspace tracing */
2716 ret = LTTCOMM_NOT_IMPLEMENTED;
2717 goto error;
2718 }
2719
2720 ret = LTTCOMM_OK;
2721
2722 error:
2723 return ret;
2724 }
2725
2726 /*
2727 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2728 */
2729 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2730 {
2731 int ret;
2732 ssize_t nb_events = 0;
2733
2734 switch (domain) {
2735 case LTTNG_DOMAIN_KERNEL:
2736 nb_events = kernel_list_events(kernel_tracer_fd, events);
2737 if (nb_events < 0) {
2738 ret = LTTCOMM_KERN_LIST_FAIL;
2739 goto error;
2740 }
2741 break;
2742 case LTTNG_DOMAIN_UST:
2743 nb_events = ust_app_list_events(events);
2744 if (nb_events < 0) {
2745 ret = LTTCOMM_UST_LIST_FAIL;
2746 goto error;
2747 }
2748 break;
2749 default:
2750 ret = LTTCOMM_NOT_IMPLEMENTED;
2751 goto error;
2752 }
2753
2754 return nb_events;
2755
2756 error:
2757 /* Return negative value to differentiate return code */
2758 return -ret;
2759 }
2760
2761 /*
2762 * Command LTTNG_START_TRACE processed by the client thread.
2763 */
2764 static int cmd_start_trace(struct ltt_session *session)
2765 {
2766 int ret;
2767 struct ltt_kernel_session *ksession;
2768 struct ltt_ust_session *usess;
2769
2770 /* Short cut */
2771 ksession = session->kernel_session;
2772 usess = session->ust_session;
2773
2774 if (session->enabled)
2775 return LTTCOMM_UST_START_FAIL;
2776 session->enabled = 1;
2777
2778 /* Kernel tracing */
2779 if (ksession != NULL) {
2780 struct ltt_kernel_channel *kchan;
2781
2782 /* Open kernel metadata */
2783 if (ksession->metadata == NULL) {
2784 ret = kernel_open_metadata(ksession, ksession->trace_path);
2785 if (ret < 0) {
2786 ret = LTTCOMM_KERN_META_FAIL;
2787 goto error;
2788 }
2789 }
2790
2791 /* Open kernel metadata stream */
2792 if (ksession->metadata_stream_fd == 0) {
2793 ret = kernel_open_metadata_stream(ksession);
2794 if (ret < 0) {
2795 ERR("Kernel create metadata stream failed");
2796 ret = LTTCOMM_KERN_STREAM_FAIL;
2797 goto error;
2798 }
2799 }
2800
2801 /* For each channel */
2802 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2803 if (kchan->stream_count == 0) {
2804 ret = kernel_open_channel_stream(kchan);
2805 if (ret < 0) {
2806 ret = LTTCOMM_KERN_STREAM_FAIL;
2807 goto error;
2808 }
2809 /* Update the stream global counter */
2810 ksession->stream_count_global += ret;
2811 }
2812 }
2813
2814 /* Setup kernel consumer socket and send fds to it */
2815 ret = init_kernel_tracing(ksession);
2816 if (ret < 0) {
2817 ret = LTTCOMM_KERN_START_FAIL;
2818 goto error;
2819 }
2820
2821 /* This start the kernel tracing */
2822 ret = kernel_start_session(ksession);
2823 if (ret < 0) {
2824 ret = LTTCOMM_KERN_START_FAIL;
2825 goto error;
2826 }
2827
2828 /* Quiescent wait after starting trace */
2829 kernel_wait_quiescent(kernel_tracer_fd);
2830 }
2831
2832 /* Flag session that trace should start automatically */
2833 if (usess) {
2834 usess->start_trace = 1;
2835
2836 ret = ust_app_start_trace_all(usess);
2837 if (ret < 0) {
2838 ret = LTTCOMM_UST_START_FAIL;
2839 goto error;
2840 }
2841 }
2842
2843 ret = LTTCOMM_OK;
2844
2845 error:
2846 return ret;
2847 }
2848
2849 /*
2850 * Command LTTNG_STOP_TRACE processed by the client thread.
2851 */
2852 static int cmd_stop_trace(struct ltt_session *session)
2853 {
2854 int ret;
2855 struct ltt_kernel_channel *kchan;
2856 struct ltt_kernel_session *ksession;
2857 struct ltt_ust_session *usess;
2858
2859 /* Short cut */
2860 ksession = session->kernel_session;
2861 usess = session->ust_session;
2862
2863 if (!session->enabled)
2864 return LTTCOMM_UST_START_FAIL;
2865 session->enabled = 0;
2866
2867 /* Kernel tracer */
2868 if (ksession != NULL) {
2869 DBG("Stop kernel tracing");
2870
2871 /* Flush all buffers before stopping */
2872 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2873 if (ret < 0) {
2874 ERR("Kernel metadata flush failed");
2875 }
2876
2877 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2878 ret = kernel_flush_buffer(kchan);
2879 if (ret < 0) {
2880 ERR("Kernel flush buffer error");
2881 }
2882 }
2883
2884 ret = kernel_stop_session(ksession);
2885 if (ret < 0) {
2886 ret = LTTCOMM_KERN_STOP_FAIL;
2887 goto error;
2888 }
2889
2890 kernel_wait_quiescent(kernel_tracer_fd);
2891 }
2892
2893 if (usess) {
2894 usess->start_trace = 0;
2895
2896 ret = ust_app_stop_trace_all(usess);
2897 if (ret < 0) {
2898 ret = LTTCOMM_UST_START_FAIL;
2899 goto error;
2900 }
2901 }
2902
2903 ret = LTTCOMM_OK;
2904
2905 error:
2906 return ret;
2907 }
2908
2909 /*
2910 * Command LTTNG_CREATE_SESSION processed by the client thread.
2911 */
2912 static int cmd_create_session(char *name, char *path)
2913 {
2914 int ret;
2915
2916 ret = session_create(name, path);
2917 if (ret != LTTCOMM_OK) {
2918 goto error;
2919 }
2920
2921 ret = LTTCOMM_OK;
2922
2923 error:
2924 return ret;
2925 }
2926
2927 /*
2928 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2929 */
2930 static int cmd_destroy_session(struct ltt_session *session, char *name)
2931 {
2932 int ret;
2933
2934 /* Clean kernel session teardown */
2935 teardown_kernel_session(session);
2936 /* UST session teardown */
2937 teardown_ust_session(session);
2938
2939 /*
2940 * Must notify the kernel thread here to update it's poll setin order
2941 * to remove the channel(s)' fd just destroyed.
2942 */
2943 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2944 if (ret < 0) {
2945 perror("write kernel poll pipe");
2946 }
2947
2948 ret = session_destroy(session);
2949
2950 return ret;
2951 }
2952
2953 /*
2954 * Command LTTNG_CALIBRATE processed by the client thread.
2955 */
2956 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2957 {
2958 int ret;
2959
2960 switch (domain) {
2961 case LTTNG_DOMAIN_KERNEL:
2962 {
2963 struct lttng_kernel_calibrate kcalibrate;
2964
2965 kcalibrate.type = calibrate->type;
2966 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2967 if (ret < 0) {
2968 ret = LTTCOMM_KERN_ENABLE_FAIL;
2969 goto error;
2970 }
2971 break;
2972 }
2973 default:
2974 /* TODO: Userspace tracing */
2975 ret = LTTCOMM_NOT_IMPLEMENTED;
2976 goto error;
2977 }
2978
2979 ret = LTTCOMM_OK;
2980
2981 error:
2982 return ret;
2983 }
2984
2985 /*
2986 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2987 */
2988 static int cmd_register_consumer(struct ltt_session *session, int domain,
2989 char *sock_path)
2990 {
2991 int ret, sock;
2992
2993 switch (domain) {
2994 case LTTNG_DOMAIN_KERNEL:
2995 /* Can't register a consumer if there is already one */
2996 if (session->kernel_session->consumer_fd != 0) {
2997 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2998 goto error;
2999 }
3000
3001 sock = lttcomm_connect_unix_sock(sock_path);
3002 if (sock < 0) {
3003 ret = LTTCOMM_CONNECT_FAIL;
3004 goto error;
3005 }
3006
3007 session->kernel_session->consumer_fd = sock;
3008 break;
3009 default:
3010 /* TODO: Userspace tracing */
3011 ret = LTTCOMM_NOT_IMPLEMENTED;
3012 goto error;
3013 }
3014
3015 ret = LTTCOMM_OK;
3016
3017 error:
3018 return ret;
3019 }
3020
3021 /*
3022 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3023 */
3024 static ssize_t cmd_list_domains(struct ltt_session *session,
3025 struct lttng_domain **domains)
3026 {
3027 int ret, index = 0;
3028 ssize_t nb_dom = 0;
3029
3030 if (session->kernel_session != NULL) {
3031 DBG3("Listing domains found kernel domain");
3032 nb_dom++;
3033 }
3034
3035 if (session->ust_session != NULL) {
3036 DBG3("Listing domains found UST global domain");
3037 nb_dom++;
3038 }
3039
3040 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3041 if (*domains == NULL) {
3042 ret = -LTTCOMM_FATAL;
3043 goto error;
3044 }
3045
3046 if (session->kernel_session != NULL) {
3047 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3048 index++;
3049 }
3050
3051 if (session->ust_session != NULL) {
3052 (*domains)[index].type = LTTNG_DOMAIN_UST;
3053 index++;
3054 }
3055
3056 return nb_dom;
3057
3058 error:
3059 return ret;
3060 }
3061
3062 /*
3063 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3064 */
3065 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3066 struct lttng_channel **channels)
3067 {
3068 int ret;
3069 ssize_t nb_chan = 0;
3070
3071 switch (domain) {
3072 case LTTNG_DOMAIN_KERNEL:
3073 if (session->kernel_session != NULL) {
3074 nb_chan = session->kernel_session->channel_count;
3075 }
3076 DBG3("Number of kernel channels %zd", nb_chan);
3077 break;
3078 case LTTNG_DOMAIN_UST:
3079 if (session->ust_session != NULL) {
3080 nb_chan = hashtable_get_count(
3081 session->ust_session->domain_global.channels);
3082 }
3083 DBG3("Number of UST global channels %zd", nb_chan);
3084 break;
3085 default:
3086 *channels = NULL;
3087 ret = -LTTCOMM_NOT_IMPLEMENTED;
3088 goto error;
3089 }
3090
3091 if (nb_chan > 0) {
3092 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3093 if (*channels == NULL) {
3094 ret = -LTTCOMM_FATAL;
3095 goto error;
3096 }
3097
3098 list_lttng_channels(domain, session, *channels);
3099 } else {
3100 *channels = NULL;
3101 }
3102
3103 return nb_chan;
3104
3105 error:
3106 return ret;
3107 }
3108
3109 /*
3110 * Command LTTNG_LIST_EVENTS processed by the client thread.
3111 */
3112 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3113 char *channel_name, struct lttng_event **events)
3114 {
3115 int ret = 0;
3116 ssize_t nb_event = 0;
3117
3118 switch (domain) {
3119 case LTTNG_DOMAIN_KERNEL:
3120 if (session->kernel_session != NULL) {
3121 nb_event = list_lttng_kernel_events(channel_name,
3122 session->kernel_session, events);
3123 }
3124 break;
3125 case LTTNG_DOMAIN_UST:
3126 {
3127 if (session->ust_session != NULL) {
3128 nb_event = list_lttng_ust_global_events(channel_name,
3129 &session->ust_session->domain_global, events);
3130 }
3131 break;
3132 }
3133 default:
3134 ret = -LTTCOMM_NOT_IMPLEMENTED;
3135 goto error;
3136 }
3137
3138 ret = nb_event;
3139
3140 error:
3141 return ret;
3142 }
3143
3144 /*
3145 * Process the command requested by the lttng client within the command
3146 * context structure. This function make sure that the return structure (llm)
3147 * is set and ready for transmission before returning.
3148 *
3149 * Return any error encountered or 0 for success.
3150 */
3151 static int process_client_msg(struct command_ctx *cmd_ctx)
3152 {
3153 int ret = LTTCOMM_OK;
3154 int need_tracing_session = 1;
3155
3156 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3157
3158 /*
3159 * Check for command that don't needs to allocate a returned payload. We do
3160 * this here so we don't have to make the call for no payload at each
3161 * command.
3162 */
3163 switch(cmd_ctx->lsm->cmd_type) {
3164 case LTTNG_LIST_SESSIONS:
3165 case LTTNG_LIST_TRACEPOINTS:
3166 case LTTNG_LIST_DOMAINS:
3167 case LTTNG_LIST_CHANNELS:
3168 case LTTNG_LIST_EVENTS:
3169 break;
3170 default:
3171 /* Setup lttng message with no payload */
3172 ret = setup_lttng_msg(cmd_ctx, 0);
3173 if (ret < 0) {
3174 /* This label does not try to unlock the session */
3175 goto init_setup_error;
3176 }
3177 }
3178
3179 /* Commands that DO NOT need a session. */
3180 switch (cmd_ctx->lsm->cmd_type) {
3181 case LTTNG_CALIBRATE:
3182 case LTTNG_CREATE_SESSION:
3183 case LTTNG_LIST_SESSIONS:
3184 case LTTNG_LIST_TRACEPOINTS:
3185 need_tracing_session = 0;
3186 break;
3187 default:
3188 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3189 session_lock_list();
3190 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3191 session_unlock_list();
3192 if (cmd_ctx->session == NULL) {
3193 if (cmd_ctx->lsm->session.name != NULL) {
3194 ret = LTTCOMM_SESS_NOT_FOUND;
3195 } else {
3196 /* If no session name specified */
3197 ret = LTTCOMM_SELECT_SESS;
3198 }
3199 goto error;
3200 } else {
3201 /* Acquire lock for the session */
3202 session_lock(cmd_ctx->session);
3203 }
3204 break;
3205 }
3206
3207 /*
3208 * Check domain type for specific "pre-action".
3209 */
3210 switch (cmd_ctx->lsm->domain.type) {
3211 case LTTNG_DOMAIN_KERNEL:
3212 /* Kernel tracer check */
3213 if (kernel_tracer_fd == 0) {
3214 /* Basically, load kernel tracer modules */
3215 init_kernel_tracer();
3216 if (kernel_tracer_fd == 0) {
3217 ret = LTTCOMM_KERN_NA;
3218 goto error;
3219 }
3220 }
3221
3222 /* Need a session for kernel command */
3223 if (need_tracing_session) {
3224 if (cmd_ctx->session->kernel_session == NULL) {
3225 ret = create_kernel_session(cmd_ctx->session);
3226 if (ret < 0) {
3227 ret = LTTCOMM_KERN_SESS_FAIL;
3228 goto error;
3229 }
3230 }
3231
3232 /* Start the kernel consumer daemon */
3233 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3234 if (kconsumer_data.pid == 0 &&
3235 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3236 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3237 ret = start_consumerd(&kconsumer_data);
3238 if (ret < 0) {
3239 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3240 goto error;
3241 }
3242 } else {
3243 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3244 }
3245 }
3246 break;
3247 case LTTNG_DOMAIN_UST:
3248 {
3249 if (need_tracing_session) {
3250 if (cmd_ctx->session->ust_session == NULL) {
3251 ret = create_ust_session(cmd_ctx->session,
3252 &cmd_ctx->lsm->domain);
3253 if (ret != LTTCOMM_OK) {
3254 goto error;
3255 }
3256 }
3257 /* Start the UST consumer daemons */
3258 /* 64-bit */
3259 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3260 if (consumerd64_path[0] != '\0' &&
3261 ustconsumer64_data.pid == 0 &&
3262 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3263 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3264 ret = start_consumerd(&ustconsumer64_data);
3265 if (ret < 0) {
3266 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3267 ust_consumerd64_fd = -EINVAL;
3268 goto error;
3269 }
3270
3271 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3272 } else {
3273 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3274 }
3275 /* 32-bit */
3276 if (consumerd32_path[0] != '\0' &&
3277 ustconsumer32_data.pid == 0 &&
3278 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3279 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3280 ret = start_consumerd(&ustconsumer32_data);
3281 if (ret < 0) {
3282 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3283 ust_consumerd32_fd = -EINVAL;
3284 goto error;
3285 }
3286 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3287 } else {
3288 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3289 }
3290 }
3291 break;
3292 }
3293 default:
3294 break;
3295 }
3296
3297 /* Process by command type */
3298 switch (cmd_ctx->lsm->cmd_type) {
3299 case LTTNG_ADD_CONTEXT:
3300 {
3301 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3302 cmd_ctx->lsm->u.context.channel_name,
3303 cmd_ctx->lsm->u.context.event_name,
3304 &cmd_ctx->lsm->u.context.ctx);
3305 break;
3306 }
3307 case LTTNG_DISABLE_CHANNEL:
3308 {
3309 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3310 cmd_ctx->lsm->u.disable.channel_name);
3311 break;
3312 }
3313 case LTTNG_DISABLE_EVENT:
3314 {
3315 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3316 cmd_ctx->lsm->u.disable.channel_name,
3317 cmd_ctx->lsm->u.disable.name);
3318 ret = LTTCOMM_OK;
3319 break;
3320 }
3321 case LTTNG_DISABLE_ALL_EVENT:
3322 {
3323 DBG("Disabling all events");
3324
3325 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3326 cmd_ctx->lsm->u.disable.channel_name);
3327 break;
3328 }
3329 case LTTNG_ENABLE_CHANNEL:
3330 {
3331 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3332 &cmd_ctx->lsm->u.channel.chan);
3333 break;
3334 }
3335 case LTTNG_ENABLE_EVENT:
3336 {
3337 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3338 cmd_ctx->lsm->u.enable.channel_name,
3339 &cmd_ctx->lsm->u.enable.event);
3340 break;
3341 }
3342 case LTTNG_ENABLE_ALL_EVENT: