Rename consumerd32_bindir -> consumerd32_path
[lttng-tools.git] / lttng-sessiond / main.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the Free
7 * Software Foundation; only version 2 of the License.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
16 * Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18
19 #define _GNU_SOURCE
20 #include <fcntl.h>
21 #include <getopt.h>
22 #include <grp.h>
23 #include <limits.h>
24 #include <pthread.h>
25 #include <semaphore.h>
26 #include <signal.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <sys/mman.h>
31 #include <sys/mount.h>
32 #include <sys/resource.h>
33 #include <sys/socket.h>
34 #include <sys/stat.h>
35 #include <sys/types.h>
36 #include <sys/wait.h>
37 #include <urcu/futex.h>
38 #include <unistd.h>
39 #include <config.h>
40
41 #include <lttng-consumerd.h>
42 #include <lttng-sessiond-comm.h>
43 #include <lttng/lttng-consumer.h>
44
45 #include <lttngerr.h>
46
47 #include "channel.h"
48 #include "compat/poll.h"
49 #include "context.h"
50 #include "event.h"
51 #include "futex.h"
52 #include "hashtable.h"
53 #include "kernel-ctl.h"
54 #include "lttng-sessiond.h"
55 #include "shm.h"
56 #include "ust-app.h"
57 #include "ust-ctl.h"
58 #include "utils.h"
59
60 #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;
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;
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 ret = ust_app_disable_channel_all(usess, uchan);
2195 if (ret < 0) {
2196 ret = LTTCOMM_UST_DISABLE_FAIL;
2197 goto error;
2198 }
2199
2200 uchan->enabled = 0;
2201
2202 break;
2203 }
2204 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2205 case LTTNG_DOMAIN_UST_EXEC_NAME:
2206 case LTTNG_DOMAIN_UST_PID:
2207 ret = LTTCOMM_NOT_IMPLEMENTED;
2208 goto error;
2209 default:
2210 ret = LTTCOMM_UNKNOWN_DOMAIN;
2211 goto error;
2212 }
2213
2214 ret = LTTCOMM_OK;
2215
2216 error:
2217 return ret;
2218 }
2219
2220 /*
2221 * Copy channel from attributes and set it in the application channel list.
2222 */
2223 /*
2224 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
2225 struct lttng_channel *attr, struct ust_app *app)
2226 {
2227 int ret;
2228 struct ltt_ust_channel *uchan, *new_chan;
2229
2230 uchan = trace_ust_get_channel_by_key(usess->channels, attr->name);
2231 if (uchan == NULL) {
2232 ret = LTTCOMM_FATAL;
2233 goto error;
2234 }
2235
2236 new_chan = trace_ust_create_channel(attr, usess->path);
2237 if (new_chan == NULL) {
2238 PERROR("malloc ltt_ust_channel");
2239 ret = LTTCOMM_FATAL;
2240 goto error;
2241 }
2242
2243 ret = channel_ust_copy(new_chan, uchan);
2244 if (ret < 0) {
2245 ret = LTTCOMM_FATAL;
2246 goto error;
2247 }
2248
2249 error:
2250 return ret;
2251 }
2252 */
2253
2254 /*
2255 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2256 */
2257 static int cmd_enable_channel(struct ltt_session *session,
2258 int domain, struct lttng_channel *attr)
2259 {
2260 int ret;
2261 struct ltt_ust_session *usess = session->ust_session;
2262
2263 DBG("Enabling channel %s for session %s", attr->name, session->name);
2264
2265 switch (domain) {
2266 case LTTNG_DOMAIN_KERNEL:
2267 {
2268 struct ltt_kernel_channel *kchan;
2269
2270 kchan = trace_kernel_get_channel_by_name(attr->name,
2271 session->kernel_session);
2272 if (kchan == NULL) {
2273 ret = channel_kernel_create(session->kernel_session,
2274 attr, kernel_poll_pipe[1]);
2275 } else {
2276 ret = channel_kernel_enable(session->kernel_session, kchan);
2277 }
2278
2279 if (ret != LTTCOMM_OK) {
2280 goto error;
2281 }
2282
2283 kernel_wait_quiescent(kernel_tracer_fd);
2284 break;
2285 }
2286 case LTTNG_DOMAIN_UST:
2287 {
2288 struct ltt_ust_channel *uchan;
2289
2290 DBG2("Enabling channel for LTTNG_DOMAIN_UST");
2291
2292 /* Get channel in global UST domain HT */
2293 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2294 attr->name);
2295 if (uchan == NULL) {
2296 uchan = trace_ust_create_channel(attr, usess->pathname);
2297 if (uchan == NULL) {
2298 ret = LTTCOMM_UST_CHAN_FAIL;
2299 goto error;
2300 }
2301
2302 rcu_read_lock();
2303 hashtable_add_unique(usess->domain_global.channels, &uchan->node);
2304 rcu_read_unlock();
2305 DBG2("UST channel %s added to global domain HT", attr->name);
2306
2307 /* Add channel to all registered applications */
2308 ret = ust_app_create_channel_all(usess, uchan);
2309 if (ret != 0) {
2310 ret = LTTCOMM_UST_CHAN_FAIL;
2311 goto error;
2312 }
2313 } else {
2314 /* If already enabled, everything is OK */
2315 if (uchan->enabled) {
2316 ret = LTTCOMM_OK;
2317 goto error;
2318 }
2319
2320 ret = ust_app_enable_channel_all(usess, uchan);
2321 if (ret < 0) {
2322 ret = LTTCOMM_UST_ENABLE_FAIL;
2323 goto error;
2324 }
2325 }
2326
2327 uchan->enabled = 1;
2328
2329 break;
2330 }
2331 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2332 case LTTNG_DOMAIN_UST_EXEC_NAME:
2333 case LTTNG_DOMAIN_UST_PID:
2334 ret = LTTCOMM_NOT_IMPLEMENTED;
2335 goto error;
2336 default:
2337 ret = LTTCOMM_UNKNOWN_DOMAIN;
2338 goto error;
2339 }
2340
2341 ret = LTTCOMM_OK;
2342
2343 error:
2344 return ret;
2345 }
2346
2347 /*
2348 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2349 */
2350 static int cmd_disable_event(struct ltt_session *session, int domain,
2351 char *channel_name, char *event_name)
2352 {
2353 int ret;
2354
2355 switch (domain) {
2356 case LTTNG_DOMAIN_KERNEL:
2357 {
2358 struct ltt_kernel_channel *kchan;
2359 struct ltt_kernel_session *ksess;
2360
2361 ksess = session->kernel_session;
2362
2363 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2364 if (kchan == NULL) {
2365 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2366 goto error;
2367 }
2368
2369 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2370 if (ret != LTTCOMM_OK) {
2371 goto error;
2372 }
2373
2374 kernel_wait_quiescent(kernel_tracer_fd);
2375 break;
2376 }
2377 case LTTNG_DOMAIN_UST:
2378 {
2379 struct ltt_ust_session *usess;
2380 struct ltt_ust_channel *uchan;
2381
2382 usess = session->ust_session;
2383
2384 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2385 channel_name);
2386 if (uchan == NULL) {
2387 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2388 goto error;
2389 }
2390
2391 ret = ust_app_disable_event(usess, uchan, event_name);
2392 if (ret < 0) {
2393 ret = LTTCOMM_UST_DISABLE_FAIL;
2394 goto error;
2395 }
2396
2397 DBG2("Disable UST event %s in channel %s completed", event_name,
2398 channel_name);
2399
2400 break;
2401 }
2402 case LTTNG_DOMAIN_UST_EXEC_NAME:
2403 case LTTNG_DOMAIN_UST_PID:
2404 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2405 default:
2406 ret = LTTCOMM_NOT_IMPLEMENTED;
2407 goto error;
2408 }
2409
2410 ret = LTTCOMM_OK;
2411
2412 error:
2413 return ret;
2414 }
2415
2416 /*
2417 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2418 */
2419 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2420 char *channel_name)
2421 {
2422 int ret;
2423
2424 switch (domain) {
2425 case LTTNG_DOMAIN_KERNEL:
2426 {
2427 struct ltt_kernel_session *ksess;
2428 struct ltt_kernel_channel *kchan;
2429
2430 ksess = session->kernel_session;
2431
2432 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2433 if (kchan == NULL) {
2434 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2435 goto error;
2436 }
2437
2438 ret = event_kernel_disable_all(ksess, kchan);
2439 if (ret != LTTCOMM_OK) {
2440 goto error;
2441 }
2442
2443 kernel_wait_quiescent(kernel_tracer_fd);
2444 break;
2445 }
2446 case LTTNG_DOMAIN_UST:
2447 {
2448 struct ltt_ust_session *usess;
2449 struct ltt_ust_channel *uchan;
2450
2451 usess = session->ust_session;
2452
2453 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2454 channel_name);
2455 if (uchan == NULL) {
2456 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2457 goto error;
2458 }
2459
2460 ret = ust_app_disable_event_all(usess, uchan);
2461 if (ret < 0) {
2462 ret = LTTCOMM_UST_DISABLE_FAIL;
2463 goto error;
2464 }
2465
2466 DBG2("Disable all UST event in channel %s completed", channel_name);
2467
2468 break;
2469 }
2470 case LTTNG_DOMAIN_UST_EXEC_NAME:
2471 case LTTNG_DOMAIN_UST_PID:
2472 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2473 default:
2474 ret = LTTCOMM_NOT_IMPLEMENTED;
2475 goto error;
2476 }
2477
2478 ret = LTTCOMM_OK;
2479
2480 error:
2481 return ret;
2482 }
2483
2484 /*
2485 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2486 */
2487 static int cmd_add_context(struct ltt_session *session, int domain,
2488 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2489 {
2490 int ret;
2491
2492 switch (domain) {
2493 case LTTNG_DOMAIN_KERNEL:
2494 /* Add kernel context to kernel tracer */
2495 ret = context_kernel_add(session->kernel_session, ctx,
2496 event_name, channel_name);
2497 if (ret != LTTCOMM_OK) {
2498 goto error;
2499 }
2500 break;
2501 case LTTNG_DOMAIN_UST:
2502 {
2503 /*
2504 struct ltt_ust_session *usess;
2505
2506 cds_list_for_each_entry(usess, &session->ust_session_list.head, list) {
2507 ret = context_ust_add(usess, ctx,
2508 event_name, channel_name, domain);
2509 if (ret != LTTCOMM_OK) {
2510 goto error;
2511 }
2512 }
2513 break;
2514 */
2515 }
2516 default:
2517 /* TODO: UST other domains */
2518 ret = LTTCOMM_NOT_IMPLEMENTED;
2519 goto error;
2520 }
2521
2522 ret = LTTCOMM_OK;
2523
2524 error:
2525 return ret;
2526 }
2527
2528 /*
2529 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2530 */
2531 static int cmd_enable_event(struct ltt_session *session, int domain,
2532 char *channel_name, struct lttng_event *event)
2533 {
2534 int ret;
2535 struct lttng_channel *attr;
2536 struct ltt_ust_session *usess = session->ust_session;
2537
2538 switch (domain) {
2539 case LTTNG_DOMAIN_KERNEL:
2540 {
2541 struct ltt_kernel_channel *kchan;
2542
2543 kchan = trace_kernel_get_channel_by_name(channel_name,
2544 session->kernel_session);
2545 if (kchan == NULL) {
2546 attr = channel_new_default_attr(domain);
2547 if (attr == NULL) {
2548 ret = LTTCOMM_FATAL;
2549 goto error;
2550 }
2551 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2552
2553 /* This call will notify the kernel thread */
2554 ret = channel_kernel_create(session->kernel_session,
2555 attr, kernel_poll_pipe[1]);
2556 if (ret != LTTCOMM_OK) {
2557 free(attr);
2558 goto error;
2559 }
2560 free(attr);
2561 }
2562
2563 /* Get the newly created kernel channel pointer */
2564 kchan = trace_kernel_get_channel_by_name(channel_name,
2565 session->kernel_session);
2566 if (kchan == NULL) {
2567 /* This sould not happen... */
2568 ret = LTTCOMM_FATAL;
2569 goto error;
2570 }
2571
2572 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2573 event);
2574 if (ret != LTTCOMM_OK) {
2575 goto error;
2576 }
2577
2578 kernel_wait_quiescent(kernel_tracer_fd);
2579 break;
2580 }
2581 case LTTNG_DOMAIN_UST:
2582 {
2583 struct ltt_ust_channel *uchan;
2584 struct ltt_ust_event *uevent;
2585 struct lttng_channel *attr;
2586
2587 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2588 channel_name);
2589 if (uchan == NULL) {
2590 /* Create default channel */
2591 attr = channel_new_default_attr(domain);
2592 if (attr == NULL) {
2593 ret = LTTCOMM_FATAL;
2594 goto error;
2595 }
2596 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2597
2598 /* Use the internal command enable channel */
2599 ret = cmd_enable_channel(session, domain, attr);
2600 if (ret < 0) {
2601 free(attr);
2602 goto error;
2603 }
2604
2605 free(attr);
2606
2607 /* Get the newly created channel reference back */
2608 uchan = trace_ust_find_channel_by_name(
2609 usess->domain_global.channels, channel_name);
2610 if (uchan == NULL) {
2611 /* Something is really wrong */
2612 ret = LTTCOMM_FATAL;
2613 goto error;
2614 }
2615 }
2616
2617 uevent = trace_ust_find_event_by_name(uchan->events, event->name);
2618 if (uevent == NULL) {
2619 uevent = trace_ust_create_event(event);
2620 if (uevent == NULL) {
2621 ret = LTTCOMM_FATAL;
2622 goto error;
2623 }
2624
2625 }
2626
2627 ret = ust_app_create_event_all(usess, uchan, uevent);
2628 if (ret < 0) {
2629 ret = LTTCOMM_UST_ENABLE_FAIL;
2630 goto error;
2631 }
2632
2633 /* Add ltt ust event to channel */
2634 rcu_read_lock();
2635 hashtable_add_unique(uchan->events, &uevent->node);
2636 rcu_read_unlock();
2637
2638 uevent->enabled = 1;
2639
2640 DBG3("UST ltt event %s added to channel %s", uevent->attr.name,
2641 uchan->name);
2642 break;
2643 }
2644 case LTTNG_DOMAIN_UST_EXEC_NAME:
2645 case LTTNG_DOMAIN_UST_PID:
2646 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2647 default:
2648 ret = LTTCOMM_NOT_IMPLEMENTED;
2649 goto error;
2650 }
2651
2652 ret = LTTCOMM_OK;
2653
2654 error:
2655 return ret;
2656 }
2657
2658 /*
2659 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2660 */
2661 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2662 char *channel_name, int event_type)
2663 {
2664 int ret;
2665 struct ltt_kernel_channel *kchan;
2666
2667 switch (domain) {
2668 case LTTNG_DOMAIN_KERNEL:
2669 kchan = trace_kernel_get_channel_by_name(channel_name,
2670 session->kernel_session);
2671 if (kchan == NULL) {
2672 /* This call will notify the kernel thread */
2673 ret = channel_kernel_create(session->kernel_session, NULL,
2674 kernel_poll_pipe[1]);
2675 if (ret != LTTCOMM_OK) {
2676 goto error;
2677 }
2678 }
2679
2680 /* Get the newly created kernel channel pointer */
2681 kchan = trace_kernel_get_channel_by_name(channel_name,
2682 session->kernel_session);
2683 if (kchan == NULL) {
2684 /* This sould not happen... */
2685 ret = LTTCOMM_FATAL;
2686 goto error;
2687 }
2688
2689 switch (event_type) {
2690 case LTTNG_KERNEL_SYSCALL:
2691 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2692 kchan, kernel_tracer_fd);
2693 break;
2694 case LTTNG_KERNEL_TRACEPOINT:
2695 /*
2696 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2697 * events already registered to the channel.
2698 */
2699 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2700 kchan, kernel_tracer_fd);
2701 break;
2702 case LTTNG_KERNEL_ALL:
2703 /* Enable syscalls and tracepoints */
2704 ret = event_kernel_enable_all(session->kernel_session,
2705 kchan, kernel_tracer_fd);
2706 break;
2707 default:
2708 ret = LTTCOMM_KERN_ENABLE_FAIL;
2709 goto error;
2710 }
2711 if (ret != LTTCOMM_OK) {
2712 goto error;
2713 }
2714
2715 kernel_wait_quiescent(kernel_tracer_fd);
2716 break;
2717 default:
2718 /* TODO: Userspace tracing */
2719 ret = LTTCOMM_NOT_IMPLEMENTED;
2720 goto error;
2721 }
2722
2723 ret = LTTCOMM_OK;
2724
2725 error:
2726 return ret;
2727 }
2728
2729 /*
2730 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2731 */
2732 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2733 {
2734 int ret;
2735 ssize_t nb_events = 0;
2736
2737 switch (domain) {
2738 case LTTNG_DOMAIN_KERNEL:
2739 nb_events = kernel_list_events(kernel_tracer_fd, events);
2740 if (nb_events < 0) {
2741 ret = LTTCOMM_KERN_LIST_FAIL;
2742 goto error;
2743 }
2744 break;
2745 case LTTNG_DOMAIN_UST:
2746 nb_events = ust_app_list_events(events);
2747 if (nb_events < 0) {
2748 ret = LTTCOMM_UST_LIST_FAIL;
2749 goto error;
2750 }
2751 break;
2752 default:
2753 ret = LTTCOMM_NOT_IMPLEMENTED;
2754 goto error;
2755 }
2756
2757 return nb_events;
2758
2759 error:
2760 /* Return negative value to differentiate return code */
2761 return -ret;
2762 }
2763
2764 /*
2765 * Command LTTNG_START_TRACE processed by the client thread.
2766 */
2767 static int cmd_start_trace(struct ltt_session *session)
2768 {
2769 int ret;
2770 struct ltt_kernel_session *ksession;
2771 struct ltt_ust_session *usess;
2772
2773 /* Short cut */
2774 ksession = session->kernel_session;
2775 usess = session->ust_session;
2776
2777 if (session->enabled)
2778 return LTTCOMM_UST_START_FAIL;
2779 session->enabled = 1;
2780
2781 /* Kernel tracing */
2782 if (ksession != NULL) {
2783 struct ltt_kernel_channel *kchan;
2784
2785 /* Open kernel metadata */
2786 if (ksession->metadata == NULL) {
2787 ret = kernel_open_metadata(ksession, ksession->trace_path);
2788 if (ret < 0) {
2789 ret = LTTCOMM_KERN_META_FAIL;
2790 goto error;
2791 }
2792 }
2793
2794 /* Open kernel metadata stream */
2795 if (ksession->metadata_stream_fd == 0) {
2796 ret = kernel_open_metadata_stream(ksession);
2797 if (ret < 0) {
2798 ERR("Kernel create metadata stream failed");
2799 ret = LTTCOMM_KERN_STREAM_FAIL;
2800 goto error;
2801 }
2802 }
2803
2804 /* For each channel */
2805 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2806 if (kchan->stream_count == 0) {
2807 ret = kernel_open_channel_stream(kchan);
2808 if (ret < 0) {
2809 ret = LTTCOMM_KERN_STREAM_FAIL;
2810 goto error;
2811 }
2812 /* Update the stream global counter */
2813 ksession->stream_count_global += ret;
2814 }
2815 }
2816
2817 /* Setup kernel consumer socket and send fds to it */
2818 ret = init_kernel_tracing(ksession);
2819 if (ret < 0) {
2820 ret = LTTCOMM_KERN_START_FAIL;
2821 goto error;
2822 }
2823
2824 /* This start the kernel tracing */
2825 ret = kernel_start_session(ksession);
2826 if (ret < 0) {
2827 ret = LTTCOMM_KERN_START_FAIL;
2828 goto error;
2829 }
2830
2831 /* Quiescent wait after starting trace */
2832 kernel_wait_quiescent(kernel_tracer_fd);
2833 }
2834
2835 /* Flag session that trace should start automatically */
2836 if (usess) {
2837 usess->start_trace = 1;
2838
2839 ret = ust_app_start_trace_all(usess);
2840 if (ret < 0) {
2841 ret = LTTCOMM_UST_START_FAIL;
2842 goto error;
2843 }
2844 }
2845
2846 ret = LTTCOMM_OK;
2847
2848 error:
2849 return ret;
2850 }
2851
2852 /*
2853 * Command LTTNG_STOP_TRACE processed by the client thread.
2854 */
2855 static int cmd_stop_trace(struct ltt_session *session)
2856 {
2857 int ret;
2858 struct ltt_kernel_channel *kchan;
2859 struct ltt_kernel_session *ksession;
2860 struct ltt_ust_session *usess;
2861
2862 /* Short cut */
2863 ksession = session->kernel_session;
2864 usess = session->ust_session;
2865
2866 if (!session->enabled)
2867 return LTTCOMM_UST_START_FAIL;
2868 session->enabled = 0;
2869
2870 /* Kernel tracer */
2871 if (ksession != NULL) {
2872 DBG("Stop kernel tracing");
2873
2874 /* Flush all buffers before stopping */
2875 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2876 if (ret < 0) {
2877 ERR("Kernel metadata flush failed");
2878 }
2879
2880 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2881 ret = kernel_flush_buffer(kchan);
2882 if (ret < 0) {
2883 ERR("Kernel flush buffer error");
2884 }
2885 }
2886
2887 ret = kernel_stop_session(ksession);
2888 if (ret < 0) {
2889 ret = LTTCOMM_KERN_STOP_FAIL;
2890 goto error;
2891 }
2892
2893 kernel_wait_quiescent(kernel_tracer_fd);
2894 }
2895
2896 if (usess) {
2897 usess->start_trace = 0;
2898
2899 ret = ust_app_stop_trace_all(usess);
2900 if (ret < 0) {
2901 ret = LTTCOMM_UST_START_FAIL;
2902 goto error;
2903 }
2904 }
2905
2906 ret = LTTCOMM_OK;
2907
2908 error:
2909 return ret;
2910 }
2911
2912 /*
2913 * Command LTTNG_CREATE_SESSION processed by the client thread.
2914 */
2915 static int cmd_create_session(char *name, char *path)
2916 {
2917 int ret;
2918
2919 ret = session_create(name, path);
2920 if (ret != LTTCOMM_OK) {
2921 goto error;
2922 }
2923
2924 ret = LTTCOMM_OK;
2925
2926 error:
2927 return ret;
2928 }
2929
2930 /*
2931 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2932 */
2933 static int cmd_destroy_session(struct ltt_session *session, char *name)
2934 {
2935 int ret;
2936
2937 /* Clean kernel session teardown */
2938 teardown_kernel_session(session);
2939 /* UST session teardown */
2940 teardown_ust_session(session);
2941
2942 /*
2943 * Must notify the kernel thread here to update it's poll setin order
2944 * to remove the channel(s)' fd just destroyed.
2945 */
2946 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2947 if (ret < 0) {
2948 perror("write kernel poll pipe");
2949 }
2950
2951 ret = session_destroy(session);
2952
2953 return ret;
2954 }
2955
2956 /*
2957 * Command LTTNG_CALIBRATE processed by the client thread.
2958 */
2959 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2960 {
2961 int ret;
2962
2963 switch (domain) {
2964 case LTTNG_DOMAIN_KERNEL:
2965 {
2966 struct lttng_kernel_calibrate kcalibrate;
2967
2968 kcalibrate.type = calibrate->type;
2969 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2970 if (ret < 0) {
2971 ret = LTTCOMM_KERN_ENABLE_FAIL;
2972 goto error;
2973 }
2974 break;
2975 }
2976 default:
2977 /* TODO: Userspace tracing */
2978 ret = LTTCOMM_NOT_IMPLEMENTED;
2979 goto error;
2980 }
2981
2982 ret = LTTCOMM_OK;
2983
2984 error:
2985 return ret;
2986 }
2987
2988 /*
2989 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2990 */
2991 static int cmd_register_consumer(struct ltt_session *session, int domain,
2992 char *sock_path)
2993 {
2994 int ret, sock;
2995
2996 switch (domain) {
2997 case LTTNG_DOMAIN_KERNEL:
2998 /* Can't register a consumer if there is already one */
2999 if (session->kernel_session->consumer_fd != 0) {
3000 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3001 goto error;
3002 }
3003
3004 sock = lttcomm_connect_unix_sock(sock_path);
3005 if (sock < 0) {
3006 ret = LTTCOMM_CONNECT_FAIL;
3007 goto error;
3008 }
3009
3010 session->kernel_session->consumer_fd = sock;
3011 break;
3012 default:
3013 /* TODO: Userspace tracing */
3014 ret = LTTCOMM_NOT_IMPLEMENTED;
3015 goto error;
3016 }
3017
3018 ret = LTTCOMM_OK;
3019
3020 error:
3021 return ret;
3022 }
3023
3024 /*
3025 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3026 */
3027 static ssize_t cmd_list_domains(struct ltt_session *session,
3028 struct lttng_domain **domains)
3029 {
3030 int ret, index = 0;
3031 ssize_t nb_dom = 0;
3032
3033 if (session->kernel_session != NULL) {
3034 DBG3("Listing domains found kernel domain");
3035 nb_dom++;
3036 }
3037
3038 if (session->ust_session != NULL) {
3039 DBG3("Listing domains found UST global domain");
3040 nb_dom++;
3041 }
3042
3043 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3044 if (*domains == NULL) {
3045 ret = -LTTCOMM_FATAL;
3046 goto error;
3047 }
3048
3049 if (session->kernel_session != NULL) {
3050 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3051 index++;
3052 }
3053
3054 if (session->ust_session != NULL) {
3055 (*domains)[index].type = LTTNG_DOMAIN_UST;
3056 index++;
3057 }
3058
3059 return nb_dom;
3060
3061 error:
3062 return ret;
3063 }
3064
3065 /*
3066 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3067 */
3068 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3069 struct lttng_channel **channels)
3070 {
3071 int ret;
3072 ssize_t nb_chan = 0;
3073
3074 switch (domain) {
3075 case LTTNG_DOMAIN_KERNEL:
3076 if (session->kernel_session != NULL) {
3077 nb_chan = session->kernel_session->channel_count;
3078 }
3079 DBG3("Number of kernel channels %zd", nb_chan);
3080 break;
3081 case LTTNG_DOMAIN_UST:
3082 if (session->ust_session != NULL) {
3083 nb_chan = hashtable_get_count(
3084 session->ust_session->domain_global.channels);
3085 }
3086 DBG3("Number of UST global channels %zd", nb_chan);
3087 break;
3088 default:
3089 *channels = NULL;
3090 ret = -LTTCOMM_NOT_IMPLEMENTED;
3091 goto error;
3092 }
3093
3094 if (nb_chan > 0) {
3095 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3096 if (*channels == NULL) {
3097 ret = -LTTCOMM_FATAL;
3098 goto error;
3099 }
3100
3101 list_lttng_channels(domain, session, *channels);
3102 } else {
3103 *channels = NULL;
3104 }
3105
3106 return nb_chan;
3107
3108 error:
3109 return ret;
3110 }
3111
3112 /*
3113 * Command LTTNG_LIST_EVENTS processed by the client thread.
3114 */
3115 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3116 char *channel_name, struct lttng_event **events)
3117 {
3118 int ret = 0;
3119 ssize_t nb_event = 0;
3120
3121 switch (domain) {
3122 case LTTNG_DOMAIN_KERNEL:
3123 if (session->kernel_session != NULL) {
3124 nb_event = list_lttng_kernel_events(channel_name,
3125 session->kernel_session, events);
3126 }
3127 break;
3128 case LTTNG_DOMAIN_UST:
3129 {
3130 if (session->ust_session != NULL) {
3131 nb_event = list_lttng_ust_global_events(channel_name,
3132 &session->ust_session->domain_global, events);
3133 }
3134 break;
3135 }
3136 default:
3137 ret = -LTTCOMM_NOT_IMPLEMENTED;
3138 goto error;
3139 }
3140
3141 ret = nb_event;
3142
3143 error:
3144 return ret;
3145 }
3146
3147 /*
3148 * Process the command requested by the lttng client within the command
3149 * context structure. This function make sure that the return structure (llm)
3150 * is set and ready for transmission before returning.
3151 *
3152 * Return any error encountered or 0 for success.
3153 */
3154 static int process_client_msg(struct command_ctx *cmd_ctx)
3155 {
3156 int ret = LTTCOMM_OK;
3157 int need_tracing_session = 1;
3158
3159 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3160
3161 /*
3162 * Check for command that don't needs to allocate a returned payload. We do
3163 * this here so we don't have to make the call for no payload at each
3164 * command.
3165 */
3166 switch(cmd_ctx->lsm->cmd_type) {
3167 case LTTNG_LIST_SESSIONS:
3168 case LTTNG_LIST_TRACEPOINTS:
3169 case LTTNG_LIST_DOMAINS:
3170 case LTTNG_LIST_CHANNELS:
3171 case LTTNG_LIST_EVENTS:
3172 break;
3173 default:
3174 /* Setup lttng message with no payload */
3175 ret = setup_lttng_msg(cmd_ctx, 0);
3176 if (ret < 0) {
3177 /* This label does not try to unlock the session */
3178 goto init_setup_error;
3179 }
3180 }
3181
3182 /* Commands that DO NOT need a session. */
3183 switch (cmd_ctx->lsm->cmd_type) {
3184 case LTTNG_CALIBRATE:
3185 case LTTNG_CREATE_SESSION:
3186 case LTTNG_LIST_SESSIONS:
3187 case LTTNG_LIST_TRACEPOINTS:
3188 need_tracing_session = 0;
3189 break;
3190 default:
3191 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3192 session_lock_list();
3193 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3194 session_unlock_list();
3195 if (cmd_ctx->session == NULL) {
3196 if (cmd_ctx->lsm->session.name != NULL) {
3197 ret = LTTCOMM_SESS_NOT_FOUND;
3198 } else {
3199 /* If no session name specified */
3200 ret = LTTCOMM_SELECT_SESS;
3201 }
3202 goto error;
3203 } else {
3204 /* Acquire lock for the session */
3205 session_lock(cmd_ctx->session);
3206 }
3207 break;
3208 }
3209
3210 /*
3211 * Check domain type for specific "pre-action".
3212 */
3213 switch (cmd_ctx->lsm->domain.type) {
3214 case LTTNG_DOMAIN_KERNEL:
3215 /* Kernel tracer check */
3216 if (kernel_tracer_fd == 0) {
3217 /* Basically, load kernel tracer modules */
3218 init_kernel_tracer();
3219 if (kernel_tracer_fd == 0) {
3220 ret = LTTCOMM_KERN_NA;
3221 goto error;
3222 }
3223 }
3224
3225 /* Need a session for kernel command */
3226 if (need_tracing_session) {
3227 if (cmd_ctx->session->kernel_session == NULL) {
3228 ret = create_kernel_session(cmd_ctx->session);
3229 if (ret < 0) {
3230 ret = LTTCOMM_KERN_SESS_FAIL;
3231 goto error;
3232 }
3233 }
3234
3235 /* Start the kernel consumer daemon */
3236 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3237 if (kconsumer_data.pid == 0 &&
3238 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3239 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3240 ret = start_consumerd(&kconsumer_data);
3241 if (ret < 0) {
3242 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3243 goto error;
3244 }
3245 } else {
3246 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3247 }
3248 }
3249 break;
3250 case LTTNG_DOMAIN_UST:
3251 {
3252 if (need_tracing_session) {
3253 if (cmd_ctx->session->ust_session == NULL) {
3254 ret = create_ust_session(cmd_ctx->session,
3255 &cmd_ctx->lsm->domain);
3256 if (ret != LTTCOMM_OK) {
3257 goto error;
3258 }
3259 }
3260 /* Start the UST consumer daemons */
3261 /* 64-bit */
3262 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3263 if (consumerd64_path[0] != '\0' &&
3264 ustconsumer64_data.pid == 0 &&
3265 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3266 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3267 ret = start_consumerd(&ustconsumer64_data);
3268 if (ret < 0) {
3269 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3270 ust_consumerd64_fd = -EINVAL;
3271 goto error;
3272 }
3273
3274 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3275 } else {
3276 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3277 }
3278 /* 32-bit */
3279 if (consumerd32_path[0] != '\0' &&
3280 ustconsumer32_data.pid == 0 &&
3281 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3282 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3283 ret = start_consumerd(&ustconsumer32_data);
3284 if (ret < 0) {
3285 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3286 ust_consumerd32_fd = -EINVAL;
3287 goto error;
3288 }
3289 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3290 } else {
3291 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3292 }
3293 }
3294 break;
3295 }
3296 default:
3297 break;
3298 }
3299
3300 /* Process by command type */
3301 switch (cmd_ctx->lsm->cmd_type) {
3302 case LTTNG_ADD_CONTEXT:
3303 {
3304 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3305 cmd_ctx->lsm->u.context.channel_name,
3306 cmd_ctx->lsm->u.context.event_name,
3307 &cmd_ctx->lsm->u.context.ctx);
3308 break;
3309 }
3310 case LTTNG_DISABLE_CHANNEL:
3311 {
3312 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3313 cmd_ctx->lsm->u.disable.channel_name);
3314 break;
3315 }
3316 case LTTNG_DISABLE_EVENT:
3317 {
3318 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3319 cmd_ctx->lsm->u.disable.channel_name,
3320 cmd_ctx->lsm->u.disable.name);
3321 ret = LTTCOMM_OK;
3322 break;
3323 }
3324 case LTTNG_DISABLE_ALL_EVENT:
3325 {
3326 DBG("Disabling all events");
3327
3328 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3329 cmd_ctx->lsm->u.disable.channel_name);
3330 break;
3331 }
3332 case LTTNG_ENABLE_CHANNEL:
3333 {
3334 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3335 &cmd_ctx->lsm->u.channel.chan);
3336 break;
3337 }
3338 case LTTNG_ENABLE_EVENT:
3339 {
3340 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3341 cmd_ctx->lsm->u.enable.channel_name,
3342 &cmd_ctx->lsm->u.enable.event);
3343 break;
3344 }