Merge branch 'master' into compat-freebsd
[lttng-tools.git] / src / bin / 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 <getopt.h>
21 #include <grp.h>
22 #include <limits.h>
23 #include <pthread.h>
24 #include <semaphore.h>
25 #include <signal.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <sys/mman.h>
30 #include <sys/mount.h>
31 #include <sys/resource.h>
32 #include <sys/socket.h>
33 #include <sys/stat.h>
34 #include <sys/types.h>
35 #include <sys/wait.h>
36 #include <urcu/futex.h>
37 #include <unistd.h>
38 #include <config.h>
39
40 #include <common/common.h>
41 #include <common/compat/poll.h>
42 #include <common/compat/socket.h>
43 #include <common/defaults.h>
44 #include <common/kernel-consumer/kernel-consumer.h>
45 #include <common/ust-consumer/ust-consumer.h>
46
47 #include "lttng-sessiond.h"
48 #include "channel.h"
49 #include "context.h"
50 #include "event.h"
51 #include "futex.h"
52 #include "kernel.h"
53 #include "modprobe.h"
54 #include "shm.h"
55 #include "ust-ctl.h"
56 #include "utils.h"
57
58 #define CONSUMERD_FILE "lttng-consumerd"
59
60 struct consumer_data {
61 enum lttng_consumer_type type;
62
63 pthread_t thread; /* Worker thread interacting with the consumer */
64 sem_t sem;
65
66 /* Mutex to control consumerd pid assignation */
67 pthread_mutex_t pid_mutex;
68 pid_t pid;
69
70 int err_sock;
71 int cmd_sock;
72
73 /* consumer error and command Unix socket path */
74 char err_unix_sock_path[PATH_MAX];
75 char cmd_unix_sock_path[PATH_MAX];
76 };
77
78 /* Const values */
79 const char default_home_dir[] = DEFAULT_HOME_DIR;
80 const char default_tracing_group[] = DEFAULT_TRACING_GROUP;
81 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
82 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
83
84 /* Variables */
85 int opt_verbose; /* Not static for lttngerr.h */
86 int opt_verbose_consumer; /* Not static for lttngerr.h */
87 int opt_quiet; /* Not static for lttngerr.h */
88
89 const char *progname;
90 const char *opt_tracing_group;
91 static int opt_sig_parent;
92 static int opt_daemon;
93 static int opt_no_kernel;
94 static int is_root; /* Set to 1 if the daemon is running as root */
95 static pid_t ppid; /* Parent PID for --sig-parent option */
96 static char *rundir;
97
98 /* Consumer daemon specific control data */
99 static struct consumer_data kconsumer_data = {
100 .type = LTTNG_CONSUMER_KERNEL,
101 .err_unix_sock_path = DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
102 .cmd_unix_sock_path = DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
103 };
104 static struct consumer_data ustconsumer64_data = {
105 .type = LTTNG_CONSUMER64_UST,
106 .err_unix_sock_path = DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
107 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
108 };
109 static struct consumer_data ustconsumer32_data = {
110 .type = LTTNG_CONSUMER32_UST,
111 .err_unix_sock_path = DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
112 .cmd_unix_sock_path = DEFAULT_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_bin = CONFIG_CONSUMERD32_BIN;
175 static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
176 static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
177 static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
178
179 static
180 void setup_consumerd_path(void)
181 {
182 const char *bin, *libdir;
183
184 /*
185 * Allow INSTALL_BIN_PATH to be used as a target path for the
186 * native architecture size consumer if CONFIG_CONSUMER*_PATH
187 * has not been defined.
188 */
189 #if (CAA_BITS_PER_LONG == 32)
190 if (!consumerd32_bin[0]) {
191 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
192 }
193 if (!consumerd32_libdir[0]) {
194 consumerd32_libdir = INSTALL_LIB_PATH;
195 }
196 #elif (CAA_BITS_PER_LONG == 64)
197 if (!consumerd64_bin[0]) {
198 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
199 }
200 if (!consumerd64_libdir[0]) {
201 consumerd64_libdir = INSTALL_LIB_PATH;
202 }
203 #else
204 #error "Unknown bitness"
205 #endif
206
207 /*
208 * runtime env. var. overrides the build default.
209 */
210 bin = getenv("LTTNG_CONSUMERD32_BIN");
211 if (bin) {
212 consumerd32_bin = bin;
213 }
214 bin = getenv("LTTNG_CONSUMERD64_BIN");
215 if (bin) {
216 consumerd64_bin = bin;
217 }
218 libdir = getenv("LTTNG_CONSUMERD32_LIBDIR");
219 if (libdir) {
220 consumerd32_libdir = libdir;
221 }
222 libdir = getenv("LTTNG_CONSUMERD64_LIBDIR");
223 if (libdir) {
224 consumerd64_libdir = libdir;
225 }
226 }
227
228 /*
229 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
230 */
231 static int create_thread_poll_set(struct lttng_poll_event *events,
232 unsigned int size)
233 {
234 int ret;
235
236 if (events == NULL || size == 0) {
237 ret = -1;
238 goto error;
239 }
240
241 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
242 if (ret < 0) {
243 goto error;
244 }
245
246 /* Add quit pipe */
247 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
248 if (ret < 0) {
249 goto error;
250 }
251
252 return 0;
253
254 error:
255 return ret;
256 }
257
258 /*
259 * Check if the thread quit pipe was triggered.
260 *
261 * Return 1 if it was triggered else 0;
262 */
263 static int check_thread_quit_pipe(int fd, uint32_t events)
264 {
265 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
266 return 1;
267 }
268
269 return 0;
270 }
271
272 /*
273 * Return group ID of the tracing group or -1 if not found.
274 */
275 static gid_t allowed_group(void)
276 {
277 struct group *grp;
278
279 if (opt_tracing_group) {
280 grp = getgrnam(opt_tracing_group);
281 } else {
282 grp = getgrnam(default_tracing_group);
283 }
284 if (!grp) {
285 return -1;
286 } else {
287 return grp->gr_gid;
288 }
289 }
290
291 /*
292 * Init thread quit pipe.
293 *
294 * Return -1 on error or 0 if all pipes are created.
295 */
296 static int init_thread_quit_pipe(void)
297 {
298 int ret, i;
299
300 ret = pipe(thread_quit_pipe);
301 if (ret < 0) {
302 PERROR("thread quit pipe");
303 goto error;
304 }
305
306 for (i = 0; i < 2; i++) {
307 ret = fcntl(thread_quit_pipe[i], F_SETFD, FD_CLOEXEC);
308 if (ret < 0) {
309 PERROR("fcntl");
310 goto error;
311 }
312 }
313
314 error:
315 return ret;
316 }
317
318 /*
319 * Complete teardown of a kernel session. This free all data structure related
320 * to a kernel session and update counter.
321 */
322 static void teardown_kernel_session(struct ltt_session *session)
323 {
324 if (!session->kernel_session) {
325 DBG3("No kernel session when tearing down session");
326 return;
327 }
328
329 DBG("Tearing down kernel session");
330
331 /*
332 * If a custom kernel consumer was registered, close the socket before
333 * tearing down the complete kernel session structure
334 */
335 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
336 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
337 }
338
339 trace_kernel_destroy_session(session->kernel_session);
340 }
341
342 /*
343 * Complete teardown of all UST sessions. This will free everything on his path
344 * and destroy the core essence of all ust sessions :)
345 */
346 static void teardown_ust_session(struct ltt_session *session)
347 {
348 int ret;
349
350 if (!session->ust_session) {
351 DBG3("No UST session when tearing down session");
352 return;
353 }
354
355 DBG("Tearing down UST session(s)");
356
357 ret = ust_app_destroy_trace_all(session->ust_session);
358 if (ret) {
359 ERR("Error in ust_app_destroy_trace_all");
360 }
361
362 trace_ust_destroy_session(session->ust_session);
363 }
364
365 /*
366 * Stop all threads by closing the thread quit pipe.
367 */
368 static void stop_threads(void)
369 {
370 int ret;
371
372 /* Stopping all threads */
373 DBG("Terminating all threads");
374 ret = notify_thread_pipe(thread_quit_pipe[1]);
375 if (ret < 0) {
376 ERR("write error on thread quit pipe");
377 }
378
379 /* Dispatch thread */
380 dispatch_thread_exit = 1;
381 futex_nto1_wake(&ust_cmd_queue.futex);
382 }
383
384 /*
385 * Cleanup the daemon
386 */
387 static void cleanup(void)
388 {
389 int ret;
390 char *cmd;
391 struct ltt_session *sess, *stmp;
392
393 DBG("Cleaning up");
394
395 DBG("Removing %s directory", rundir);
396 ret = asprintf(&cmd, "rm -rf %s", rundir);
397 if (ret < 0) {
398 ERR("asprintf failed. Something is really wrong!");
399 }
400
401 /* Remove lttng run directory */
402 ret = system(cmd);
403 if (ret < 0) {
404 ERR("Unable to clean %s", rundir);
405 }
406 free(cmd);
407
408 DBG("Cleaning up all sessions");
409
410 /* Destroy session list mutex */
411 if (session_list_ptr != NULL) {
412 pthread_mutex_destroy(&session_list_ptr->lock);
413
414 /* Cleanup ALL session */
415 cds_list_for_each_entry_safe(sess, stmp,
416 &session_list_ptr->head, list) {
417 teardown_kernel_session(sess);
418 teardown_ust_session(sess);
419 free(sess);
420 }
421 }
422
423 DBG("Closing all UST sockets");
424 ust_app_clean_list();
425
426 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
427
428 if (is_root && !opt_no_kernel) {
429 DBG2("Closing kernel fd");
430 close(kernel_tracer_fd);
431 DBG("Unloading kernel modules");
432 modprobe_remove_lttng_all();
433 }
434
435 close(thread_quit_pipe[0]);
436 close(thread_quit_pipe[1]);
437
438 /* <fun> */
439 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
440 "Matthew, BEET driven development works!%c[%dm",
441 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
442 /* </fun> */
443 }
444
445 /*
446 * Send data on a unix socket using the liblttsessiondcomm API.
447 *
448 * Return lttcomm error code.
449 */
450 static int send_unix_sock(int sock, void *buf, size_t len)
451 {
452 /* Check valid length */
453 if (len <= 0) {
454 return -1;
455 }
456
457 return lttcomm_send_unix_sock(sock, buf, len);
458 }
459
460 /*
461 * Free memory of a command context structure.
462 */
463 static void clean_command_ctx(struct command_ctx **cmd_ctx)
464 {
465 DBG("Clean command context structure");
466 if (*cmd_ctx) {
467 if ((*cmd_ctx)->llm) {
468 free((*cmd_ctx)->llm);
469 }
470 if ((*cmd_ctx)->lsm) {
471 free((*cmd_ctx)->lsm);
472 }
473 free(*cmd_ctx);
474 *cmd_ctx = NULL;
475 }
476 }
477
478 /*
479 * Send all stream fds of kernel channel to the consumer.
480 */
481 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
482 int sock, struct ltt_kernel_channel *channel,
483 uid_t uid, gid_t gid)
484 {
485 int ret;
486 struct ltt_kernel_stream *stream;
487 struct lttcomm_consumer_msg lkm;
488
489 DBG("Sending streams of channel %s to kernel consumer",
490 channel->channel->name);
491
492 /* Send channel */
493 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
494 lkm.u.channel.channel_key = channel->fd;
495 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
496 lkm.u.channel.mmap_len = 0; /* for kernel */
497 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
498 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
499 if (ret < 0) {
500 perror("send consumer channel");
501 goto error;
502 }
503
504 /* Send streams */
505 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
506 if (!stream->fd) {
507 continue;
508 }
509 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
510 lkm.u.stream.channel_key = channel->fd;
511 lkm.u.stream.stream_key = stream->fd;
512 lkm.u.stream.state = stream->state;
513 lkm.u.stream.output = channel->channel->attr.output;
514 lkm.u.stream.mmap_len = 0; /* for kernel */
515 lkm.u.stream.uid = uid;
516 lkm.u.stream.gid = gid;
517 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
518 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
519 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
520 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
521 if (ret < 0) {
522 perror("send consumer stream");
523 goto error;
524 }
525 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
526 if (ret < 0) {
527 perror("send consumer stream ancillary data");
528 goto error;
529 }
530 }
531
532 DBG("consumer channel streams sent");
533
534 return 0;
535
536 error:
537 return ret;
538 }
539
540 /*
541 * Send all stream fds of the kernel session to the consumer.
542 */
543 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
544 struct ltt_kernel_session *session)
545 {
546 int ret;
547 struct ltt_kernel_channel *chan;
548 struct lttcomm_consumer_msg lkm;
549 int sock = session->consumer_fd;
550
551 DBG("Sending metadata stream fd");
552
553 /* Extra protection. It's NOT supposed to be set to 0 at this point */
554 if (session->consumer_fd == 0) {
555 session->consumer_fd = consumer_data->cmd_sock;
556 }
557
558 if (session->metadata_stream_fd != 0) {
559 /* Send metadata channel fd */
560 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
561 lkm.u.channel.channel_key = session->metadata->fd;
562 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
563 lkm.u.channel.mmap_len = 0; /* for kernel */
564 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
565 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
566 if (ret < 0) {
567 perror("send consumer channel");
568 goto error;
569 }
570
571 /* Send metadata stream fd */
572 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
573 lkm.u.stream.channel_key = session->metadata->fd;
574 lkm.u.stream.stream_key = session->metadata_stream_fd;
575 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
576 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
577 lkm.u.stream.mmap_len = 0; /* for kernel */
578 lkm.u.stream.uid = session->uid;
579 lkm.u.stream.gid = session->gid;
580 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
581 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
582 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
583 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
584 if (ret < 0) {
585 perror("send consumer stream");
586 goto error;
587 }
588 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
589 if (ret < 0) {
590 perror("send consumer stream");
591 goto error;
592 }
593 }
594
595 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
596 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
597 session->uid, session->gid);
598 if (ret < 0) {
599 goto error;
600 }
601 }
602
603 DBG("consumer fds (metadata and channel streams) sent");
604
605 return 0;
606
607 error:
608 return ret;
609 }
610
611 /*
612 * Notify UST applications using the shm mmap futex.
613 */
614 static int notify_ust_apps(int active)
615 {
616 char *wait_shm_mmap;
617
618 DBG("Notifying applications of session daemon state: %d", active);
619
620 /* See shm.c for this call implying mmap, shm and futex calls */
621 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
622 if (wait_shm_mmap == NULL) {
623 goto error;
624 }
625
626 /* Wake waiting process */
627 futex_wait_update((int32_t *) wait_shm_mmap, active);
628
629 /* Apps notified successfully */
630 return 0;
631
632 error:
633 return -1;
634 }
635
636 /*
637 * Setup the outgoing data buffer for the response (llm) by allocating the
638 * right amount of memory and copying the original information from the lsm
639 * structure.
640 *
641 * Return total size of the buffer pointed by buf.
642 */
643 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
644 {
645 int ret, buf_size;
646
647 buf_size = size;
648
649 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
650 if (cmd_ctx->llm == NULL) {
651 perror("zmalloc");
652 ret = -ENOMEM;
653 goto error;
654 }
655
656 /* Copy common data */
657 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
658 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
659
660 cmd_ctx->llm->data_size = size;
661 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
662
663 return buf_size;
664
665 error:
666 return ret;
667 }
668
669 /*
670 * Update the kernel poll set of all channel fd available over all tracing
671 * session. Add the wakeup pipe at the end of the set.
672 */
673 static int update_kernel_poll(struct lttng_poll_event *events)
674 {
675 int ret;
676 struct ltt_session *session;
677 struct ltt_kernel_channel *channel;
678
679 DBG("Updating kernel poll set");
680
681 session_lock_list();
682 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
683 session_lock(session);
684 if (session->kernel_session == NULL) {
685 session_unlock(session);
686 continue;
687 }
688
689 cds_list_for_each_entry(channel,
690 &session->kernel_session->channel_list.head, list) {
691 /* Add channel fd to the kernel poll set */
692 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
693 if (ret < 0) {
694 session_unlock(session);
695 goto error;
696 }
697 DBG("Channel fd %d added to kernel set", channel->fd);
698 }
699 session_unlock(session);
700 }
701 session_unlock_list();
702
703 return 0;
704
705 error:
706 session_unlock_list();
707 return -1;
708 }
709
710 /*
711 * Find the channel fd from 'fd' over all tracing session. When found, check
712 * for new channel stream and send those stream fds to the kernel consumer.
713 *
714 * Useful for CPU hotplug feature.
715 */
716 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
717 {
718 int ret = 0;
719 struct ltt_session *session;
720 struct ltt_kernel_channel *channel;
721
722 DBG("Updating kernel streams for channel fd %d", fd);
723
724 session_lock_list();
725 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
726 session_lock(session);
727 if (session->kernel_session == NULL) {
728 session_unlock(session);
729 continue;
730 }
731
732 /* This is not suppose to be 0 but this is an extra security check */
733 if (session->kernel_session->consumer_fd == 0) {
734 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
735 }
736
737 cds_list_for_each_entry(channel,
738 &session->kernel_session->channel_list.head, list) {
739 if (channel->fd == fd) {
740 DBG("Channel found, updating kernel streams");
741 ret = kernel_open_channel_stream(channel);
742 if (ret < 0) {
743 goto error;
744 }
745
746 /*
747 * Have we already sent fds to the consumer? If yes, it means
748 * that tracing is started so it is safe to send our updated
749 * stream fds.
750 */
751 if (session->kernel_session->consumer_fds_sent == 1) {
752 ret = send_kconsumer_channel_streams(consumer_data,
753 session->kernel_session->consumer_fd, channel,
754 session->uid, session->gid);
755 if (ret < 0) {
756 goto error;
757 }
758 }
759 goto error;
760 }
761 }
762 session_unlock(session);
763 }
764 session_unlock_list();
765 return ret;
766
767 error:
768 session_unlock(session);
769 session_unlock_list();
770 return ret;
771 }
772
773 /*
774 * For each tracing session, update newly registered apps.
775 */
776 static void update_ust_app(int app_sock)
777 {
778 struct ltt_session *sess, *stmp;
779
780 session_lock_list();
781
782 /* For all tracing session(s) */
783 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
784 session_lock(sess);
785 if (sess->ust_session) {
786 ust_app_global_update(sess->ust_session, app_sock);
787 }
788 session_unlock(sess);
789 }
790
791 session_unlock_list();
792 }
793
794 /*
795 * This thread manage event coming from the kernel.
796 *
797 * Features supported in this thread:
798 * -) CPU Hotplug
799 */
800 static void *thread_manage_kernel(void *data)
801 {
802 int ret, i, pollfd, update_poll_flag = 1;
803 uint32_t revents, nb_fd;
804 char tmp;
805 struct lttng_poll_event events;
806
807 DBG("Thread manage kernel started");
808
809 ret = create_thread_poll_set(&events, 2);
810 if (ret < 0) {
811 goto error;
812 }
813
814 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
815 if (ret < 0) {
816 goto error;
817 }
818
819 while (1) {
820 if (update_poll_flag == 1) {
821 /*
822 * Reset number of fd in the poll set. Always 2 since there is the thread
823 * quit pipe and the kernel pipe.
824 */
825 events.nb_fd = 2;
826
827 ret = update_kernel_poll(&events);
828 if (ret < 0) {
829 goto error;
830 }
831 update_poll_flag = 0;
832 }
833
834 nb_fd = LTTNG_POLL_GETNB(&events);
835
836 DBG("Thread kernel polling on %d fds", nb_fd);
837
838 /* Zeroed the poll events */
839 lttng_poll_reset(&events);
840
841 /* Poll infinite value of time */
842 ret = lttng_poll_wait(&events, -1);
843 if (ret < 0) {
844 goto error;
845 } else if (ret == 0) {
846 /* Should not happen since timeout is infinite */
847 ERR("Return value of poll is 0 with an infinite timeout.\n"
848 "This should not have happened! Continuing...");
849 continue;
850 }
851
852 for (i = 0; i < nb_fd; i++) {
853 /* Fetch once the poll data */
854 revents = LTTNG_POLL_GETEV(&events, i);
855 pollfd = LTTNG_POLL_GETFD(&events, i);
856
857 /* Thread quit pipe has been closed. Killing thread. */
858 ret = check_thread_quit_pipe(pollfd, revents);
859 if (ret) {
860 goto error;
861 }
862
863 /* Check for data on kernel pipe */
864 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
865 ret = read(kernel_poll_pipe[0], &tmp, 1);
866 update_poll_flag = 1;
867 continue;
868 } else {
869 /*
870 * New CPU detected by the kernel. Adding kernel stream to
871 * kernel session and updating the kernel consumer
872 */
873 if (revents & LPOLLIN) {
874 ret = update_kernel_stream(&kconsumer_data, pollfd);
875 if (ret < 0) {
876 continue;
877 }
878 break;
879 /*
880 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
881 * and unregister kernel stream at this point.
882 */
883 }
884 }
885 }
886 }
887
888 error:
889 DBG("Kernel thread dying");
890 close(kernel_poll_pipe[0]);
891 close(kernel_poll_pipe[1]);
892
893 lttng_poll_clean(&events);
894
895 return NULL;
896 }
897
898 /*
899 * This thread manage the consumer error sent back to the session daemon.
900 */
901 static void *thread_manage_consumer(void *data)
902 {
903 int sock = 0, i, ret, pollfd;
904 uint32_t revents, nb_fd;
905 enum lttcomm_return_code code;
906 struct lttng_poll_event events;
907 struct consumer_data *consumer_data = data;
908
909 DBG("[thread] Manage consumer started");
910
911 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
912 if (ret < 0) {
913 goto error;
914 }
915
916 /*
917 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
918 * Nothing more will be added to this poll set.
919 */
920 ret = create_thread_poll_set(&events, 2);
921 if (ret < 0) {
922 goto error;
923 }
924
925 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
926 if (ret < 0) {
927 goto error;
928 }
929
930 nb_fd = LTTNG_POLL_GETNB(&events);
931
932 /* Inifinite blocking call, waiting for transmission */
933 ret = lttng_poll_wait(&events, -1);
934 if (ret < 0) {
935 goto error;
936 }
937
938 for (i = 0; i < nb_fd; i++) {
939 /* Fetch once the poll data */
940 revents = LTTNG_POLL_GETEV(&events, i);
941 pollfd = LTTNG_POLL_GETFD(&events, i);
942
943 /* Thread quit pipe has been closed. Killing thread. */
944 ret = check_thread_quit_pipe(pollfd, revents);
945 if (ret) {
946 goto error;
947 }
948
949 /* Event on the registration socket */
950 if (pollfd == consumer_data->err_sock) {
951 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
952 ERR("consumer err socket poll error");
953 goto error;
954 }
955 }
956 }
957
958 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
959 if (sock < 0) {
960 goto error;
961 }
962
963 DBG2("Receiving code from consumer err_sock");
964
965 /* Getting status code from kconsumerd */
966 ret = lttcomm_recv_unix_sock(sock, &code,
967 sizeof(enum lttcomm_return_code));
968 if (ret <= 0) {
969 goto error;
970 }
971
972 if (code == CONSUMERD_COMMAND_SOCK_READY) {
973 consumer_data->cmd_sock =
974 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
975 if (consumer_data->cmd_sock < 0) {
976 sem_post(&consumer_data->sem);
977 PERROR("consumer connect");
978 goto error;
979 }
980 /* Signal condition to tell that the kconsumerd is ready */
981 sem_post(&consumer_data->sem);
982 DBG("consumer command socket ready");
983 } else {
984 ERR("consumer error when waiting for SOCK_READY : %s",
985 lttcomm_get_readable_code(-code));
986 goto error;
987 }
988
989 /* Remove the kconsumerd error sock since we've established a connexion */
990 ret = lttng_poll_del(&events, consumer_data->err_sock);
991 if (ret < 0) {
992 goto error;
993 }
994
995 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
996 if (ret < 0) {
997 goto error;
998 }
999
1000 /* Update number of fd */
1001 nb_fd = LTTNG_POLL_GETNB(&events);
1002
1003 /* Inifinite blocking call, waiting for transmission */
1004 ret = lttng_poll_wait(&events, -1);
1005 if (ret < 0) {
1006 goto error;
1007 }
1008
1009 for (i = 0; i < nb_fd; i++) {
1010 /* Fetch once the poll data */
1011 revents = LTTNG_POLL_GETEV(&events, i);
1012 pollfd = LTTNG_POLL_GETFD(&events, i);
1013
1014 /* Thread quit pipe has been closed. Killing thread. */
1015 ret = check_thread_quit_pipe(pollfd, revents);
1016 if (ret) {
1017 goto error;
1018 }
1019
1020 /* Event on the kconsumerd socket */
1021 if (pollfd == sock) {
1022 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1023 ERR("consumer err socket second poll error");
1024 goto error;
1025 }
1026 }
1027 }
1028
1029 /* Wait for any kconsumerd error */
1030 ret = lttcomm_recv_unix_sock(sock, &code,
1031 sizeof(enum lttcomm_return_code));
1032 if (ret <= 0) {
1033 ERR("consumer closed the command socket");
1034 goto error;
1035 }
1036
1037 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1038
1039 error:
1040 DBG("consumer thread dying");
1041 close(consumer_data->err_sock);
1042 close(consumer_data->cmd_sock);
1043 close(sock);
1044
1045 unlink(consumer_data->err_unix_sock_path);
1046 unlink(consumer_data->cmd_unix_sock_path);
1047 consumer_data->pid = 0;
1048
1049 lttng_poll_clean(&events);
1050
1051 return NULL;
1052 }
1053
1054 /*
1055 * This thread manage application communication.
1056 */
1057 static void *thread_manage_apps(void *data)
1058 {
1059 int i, ret, pollfd;
1060 uint32_t revents, nb_fd;
1061 struct ust_command ust_cmd;
1062 struct lttng_poll_event events;
1063
1064 DBG("[thread] Manage application started");
1065
1066 rcu_register_thread();
1067 rcu_thread_online();
1068
1069 ret = create_thread_poll_set(&events, 2);
1070 if (ret < 0) {
1071 goto error;
1072 }
1073
1074 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1075 if (ret < 0) {
1076 goto error;
1077 }
1078
1079 while (1) {
1080 /* Zeroed the events structure */
1081 lttng_poll_reset(&events);
1082
1083 nb_fd = LTTNG_POLL_GETNB(&events);
1084
1085 DBG("Apps thread polling on %d fds", nb_fd);
1086
1087 /* Inifinite blocking call, waiting for transmission */
1088 ret = lttng_poll_wait(&events, -1);
1089 if (ret < 0) {
1090 goto error;
1091 }
1092
1093 for (i = 0; i < nb_fd; i++) {
1094 /* Fetch once the poll data */
1095 revents = LTTNG_POLL_GETEV(&events, i);
1096 pollfd = LTTNG_POLL_GETFD(&events, i);
1097
1098 /* Thread quit pipe has been closed. Killing thread. */
1099 ret = check_thread_quit_pipe(pollfd, revents);
1100 if (ret) {
1101 goto error;
1102 }
1103
1104 /* Inspect the apps cmd pipe */
1105 if (pollfd == apps_cmd_pipe[0]) {
1106 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1107 ERR("Apps command pipe error");
1108 goto error;
1109 } else if (revents & LPOLLIN) {
1110 /* Empty pipe */
1111 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1112 if (ret < 0 || ret < sizeof(ust_cmd)) {
1113 perror("read apps cmd pipe");
1114 goto error;
1115 }
1116
1117 /* Register applicaton to the session daemon */
1118 ret = ust_app_register(&ust_cmd.reg_msg,
1119 ust_cmd.sock);
1120 if (ret == -ENOMEM) {
1121 goto error;
1122 } else if (ret < 0) {
1123 break;
1124 }
1125
1126 /*
1127 * Validate UST version compatibility.
1128 */
1129 ret = ust_app_validate_version(ust_cmd.sock);
1130 if (ret >= 0) {
1131 /*
1132 * Add channel(s) and event(s) to newly registered apps
1133 * from lttng global UST domain.
1134 */
1135 update_ust_app(ust_cmd.sock);
1136 }
1137
1138 ret = ust_app_register_done(ust_cmd.sock);
1139 if (ret < 0) {
1140 /*
1141 * If the registration is not possible, we simply
1142 * unregister the apps and continue
1143 */
1144 ust_app_unregister(ust_cmd.sock);
1145 } else {
1146 /*
1147 * We just need here to monitor the close of the UST
1148 * socket and poll set monitor those by default.
1149 */
1150 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1151 if (ret < 0) {
1152 goto error;
1153 }
1154
1155 DBG("Apps with sock %d added to poll set",
1156 ust_cmd.sock);
1157 }
1158
1159 break;
1160 }
1161 } else {
1162 /*
1163 * At this point, we know that a registered application made
1164 * the event at poll_wait.
1165 */
1166 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1167 /* Removing from the poll set */
1168 ret = lttng_poll_del(&events, pollfd);
1169 if (ret < 0) {
1170 goto error;
1171 }
1172
1173 /* Socket closed on remote end. */
1174 ust_app_unregister(pollfd);
1175 break;
1176 }
1177 }
1178 }
1179 }
1180
1181 error:
1182 DBG("Application communication apps dying");
1183 close(apps_cmd_pipe[0]);
1184 close(apps_cmd_pipe[1]);
1185
1186 lttng_poll_clean(&events);
1187
1188 rcu_thread_offline();
1189 rcu_unregister_thread();
1190 return NULL;
1191 }
1192
1193 /*
1194 * Dispatch request from the registration threads to the application
1195 * communication thread.
1196 */
1197 static void *thread_dispatch_ust_registration(void *data)
1198 {
1199 int ret;
1200 struct cds_wfq_node *node;
1201 struct ust_command *ust_cmd = NULL;
1202
1203 DBG("[thread] Dispatch UST command started");
1204
1205 while (!dispatch_thread_exit) {
1206 /* Atomically prepare the queue futex */
1207 futex_nto1_prepare(&ust_cmd_queue.futex);
1208
1209 do {
1210 /* Dequeue command for registration */
1211 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1212 if (node == NULL) {
1213 DBG("Woken up but nothing in the UST command queue");
1214 /* Continue thread execution */
1215 break;
1216 }
1217
1218 ust_cmd = caa_container_of(node, struct ust_command, node);
1219
1220 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1221 " gid:%d sock:%d name:%s (version %d.%d)",
1222 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1223 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1224 ust_cmd->sock, ust_cmd->reg_msg.name,
1225 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1226 /*
1227 * Inform apps thread of the new application registration. This
1228 * call is blocking so we can be assured that the data will be read
1229 * at some point in time or wait to the end of the world :)
1230 */
1231 ret = write(apps_cmd_pipe[1], ust_cmd,
1232 sizeof(struct ust_command));
1233 if (ret < 0) {
1234 perror("write apps cmd pipe");
1235 if (errno == EBADF) {
1236 /*
1237 * We can't inform the application thread to process
1238 * registration. We will exit or else application
1239 * registration will not occur and tracing will never
1240 * start.
1241 */
1242 goto error;
1243 }
1244 }
1245 free(ust_cmd);
1246 } while (node != NULL);
1247
1248 /* Futex wait on queue. Blocking call on futex() */
1249 futex_nto1_wait(&ust_cmd_queue.futex);
1250 }
1251
1252 error:
1253 DBG("Dispatch thread dying");
1254 return NULL;
1255 }
1256
1257 /*
1258 * This thread manage application registration.
1259 */
1260 static void *thread_registration_apps(void *data)
1261 {
1262 int sock = 0, i, ret, pollfd;
1263 uint32_t revents, nb_fd;
1264 struct lttng_poll_event events;
1265 /*
1266 * Get allocated in this thread, enqueued to a global queue, dequeued and
1267 * freed in the manage apps thread.
1268 */
1269 struct ust_command *ust_cmd = NULL;
1270
1271 DBG("[thread] Manage application registration started");
1272
1273 ret = lttcomm_listen_unix_sock(apps_sock);
1274 if (ret < 0) {
1275 goto error;
1276 }
1277
1278 /*
1279 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1280 * more will be added to this poll set.
1281 */
1282 ret = create_thread_poll_set(&events, 2);
1283 if (ret < 0) {
1284 goto error;
1285 }
1286
1287 /* Add the application registration socket */
1288 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1289 if (ret < 0) {
1290 goto error;
1291 }
1292
1293 /* Notify all applications to register */
1294 ret = notify_ust_apps(1);
1295 if (ret < 0) {
1296 ERR("Failed to notify applications or create the wait shared memory.\n"
1297 "Execution continues but there might be problem for already\n"
1298 "running applications that wishes to register.");
1299 }
1300
1301 while (1) {
1302 DBG("Accepting application registration");
1303
1304 nb_fd = LTTNG_POLL_GETNB(&events);
1305
1306 /* Inifinite blocking call, waiting for transmission */
1307 ret = lttng_poll_wait(&events, -1);
1308 if (ret < 0) {
1309 goto error;
1310 }
1311
1312 for (i = 0; i < nb_fd; i++) {
1313 /* Fetch once the poll data */
1314 revents = LTTNG_POLL_GETEV(&events, i);
1315 pollfd = LTTNG_POLL_GETFD(&events, i);
1316
1317 /* Thread quit pipe has been closed. Killing thread. */
1318 ret = check_thread_quit_pipe(pollfd, revents);
1319 if (ret) {
1320 goto error;
1321 }
1322
1323 /* Event on the registration socket */
1324 if (pollfd == apps_sock) {
1325 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1326 ERR("Register apps socket poll error");
1327 goto error;
1328 } else if (revents & LPOLLIN) {
1329 sock = lttcomm_accept_unix_sock(apps_sock);
1330 if (sock < 0) {
1331 goto error;
1332 }
1333
1334 /* Create UST registration command for enqueuing */
1335 ust_cmd = zmalloc(sizeof(struct ust_command));
1336 if (ust_cmd == NULL) {
1337 perror("ust command zmalloc");
1338 goto error;
1339 }
1340
1341 /*
1342 * Using message-based transmissions to ensure we don't
1343 * have to deal with partially received messages.
1344 */
1345 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1346 sizeof(struct ust_register_msg));
1347 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1348 if (ret < 0) {
1349 perror("lttcomm_recv_unix_sock register apps");
1350 } else {
1351 ERR("Wrong size received on apps register");
1352 }
1353 free(ust_cmd);
1354 close(sock);
1355 continue;
1356 }
1357
1358 ust_cmd->sock = sock;
1359
1360 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1361 " gid:%d sock:%d name:%s (version %d.%d)",
1362 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1363 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1364 ust_cmd->sock, ust_cmd->reg_msg.name,
1365 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1366
1367 /*
1368 * Lock free enqueue the registration request. The red pill
1369 * has been taken! This apps will be part of the *system*.
1370 */
1371 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1372
1373 /*
1374 * Wake the registration queue futex. Implicit memory
1375 * barrier with the exchange in cds_wfq_enqueue.
1376 */
1377 futex_nto1_wake(&ust_cmd_queue.futex);
1378 }
1379 }
1380 }
1381 }
1382
1383 error:
1384 DBG("UST Registration thread dying");
1385
1386 /* Notify that the registration thread is gone */
1387 notify_ust_apps(0);
1388
1389 close(apps_sock);
1390 close(sock);
1391 unlink(apps_unix_sock_path);
1392
1393 lttng_poll_clean(&events);
1394
1395 return NULL;
1396 }
1397
1398 /*
1399 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1400 * exec or it will fails.
1401 */
1402 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1403 {
1404 int ret;
1405 struct timespec timeout;
1406
1407 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1408 timeout.tv_nsec = 0;
1409
1410 /* Setup semaphore */
1411 ret = sem_init(&consumer_data->sem, 0, 0);
1412 if (ret < 0) {
1413 PERROR("sem_init consumer semaphore");
1414 goto error;
1415 }
1416
1417 ret = pthread_create(&consumer_data->thread, NULL,
1418 thread_manage_consumer, consumer_data);
1419 if (ret != 0) {
1420 PERROR("pthread_create consumer");
1421 ret = -1;
1422 goto error;
1423 }
1424
1425 /* Get time for sem_timedwait absolute timeout */
1426 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1427 if (ret < 0) {
1428 PERROR("clock_gettime spawn consumer");
1429 /* Infinite wait for the kconsumerd thread to be ready */
1430 ret = sem_wait(&consumer_data->sem);
1431 } else {
1432 /* Normal timeout if the gettime was successful */
1433 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1434 ret = sem_timedwait(&consumer_data->sem, &timeout);
1435 }
1436
1437 if (ret < 0) {
1438 if (errno == ETIMEDOUT) {
1439 /*
1440 * Call has timed out so we kill the kconsumerd_thread and return
1441 * an error.
1442 */
1443 ERR("The consumer thread was never ready. Killing it");
1444 ret = pthread_cancel(consumer_data->thread);
1445 if (ret < 0) {
1446 PERROR("pthread_cancel consumer thread");
1447 }
1448 } else {
1449 PERROR("semaphore wait failed consumer thread");
1450 }
1451 goto error;
1452 }
1453
1454 pthread_mutex_lock(&consumer_data->pid_mutex);
1455 if (consumer_data->pid == 0) {
1456 ERR("Kconsumerd did not start");
1457 pthread_mutex_unlock(&consumer_data->pid_mutex);
1458 goto error;
1459 }
1460 pthread_mutex_unlock(&consumer_data->pid_mutex);
1461
1462 return 0;
1463
1464 error:
1465 return ret;
1466 }
1467
1468 /*
1469 * Join consumer thread
1470 */
1471 static int join_consumer_thread(struct consumer_data *consumer_data)
1472 {
1473 void *status;
1474 int ret;
1475
1476 if (consumer_data->pid != 0) {
1477 ret = kill(consumer_data->pid, SIGTERM);
1478 if (ret) {
1479 ERR("Error killing consumer daemon");
1480 return ret;
1481 }
1482 return pthread_join(consumer_data->thread, &status);
1483 } else {
1484 return 0;
1485 }
1486 }
1487
1488 /*
1489 * Fork and exec a consumer daemon (consumerd).
1490 *
1491 * Return pid if successful else -1.
1492 */
1493 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1494 {
1495 int ret;
1496 pid_t pid;
1497 const char *consumer_to_use;
1498 const char *verbosity;
1499 struct stat st;
1500
1501 DBG("Spawning consumerd");
1502
1503 pid = fork();
1504 if (pid == 0) {
1505 /*
1506 * Exec consumerd.
1507 */
1508 if (opt_verbose_consumer) {
1509 verbosity = "--verbose";
1510 } else {
1511 verbosity = "--quiet";
1512 }
1513 switch (consumer_data->type) {
1514 case LTTNG_CONSUMER_KERNEL:
1515 /*
1516 * Find out which consumerd to execute. We will first try the
1517 * 64-bit path, then the sessiond's installation directory, and
1518 * fallback on the 32-bit one,
1519 */
1520 DBG3("Looking for a kernel consumer at these locations:");
1521 DBG3(" 1) %s", consumerd64_bin);
1522 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1523 DBG3(" 3) %s", consumerd32_bin);
1524 if (stat(consumerd64_bin, &st) == 0) {
1525 DBG3("Found location #1");
1526 consumer_to_use = consumerd64_bin;
1527 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1528 DBG3("Found location #2");
1529 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1530 } else if (stat(consumerd32_bin, &st) == 0) {
1531 DBG3("Found location #3");
1532 consumer_to_use = consumerd32_bin;
1533 } else {
1534 DBG("Could not find any valid consumerd executable");
1535 break;
1536 }
1537 DBG("Using kernel consumer at: %s", consumer_to_use);
1538 execl(consumer_to_use,
1539 "lttng-consumerd", verbosity, "-k",
1540 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1541 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1542 NULL);
1543 break;
1544 case LTTNG_CONSUMER64_UST:
1545 {
1546 char *tmpnew = NULL;
1547
1548 if (consumerd64_libdir[0] != '\0') {
1549 char *tmp;
1550 size_t tmplen;
1551
1552 tmp = getenv("LD_LIBRARY_PATH");
1553 if (!tmp) {
1554 tmp = "";
1555 }
1556 tmplen = strlen("LD_LIBRARY_PATH=")
1557 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1558 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1559 if (!tmpnew) {
1560 ret = -ENOMEM;
1561 goto error;
1562 }
1563 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1564 strcat(tmpnew, consumerd64_libdir);
1565 if (tmp[0] != '\0') {
1566 strcat(tmpnew, ":");
1567 strcat(tmpnew, tmp);
1568 }
1569 ret = putenv(tmpnew);
1570 if (ret) {
1571 ret = -errno;
1572 goto error;
1573 }
1574 }
1575 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1576 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1577 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1578 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1579 NULL);
1580 if (consumerd64_libdir[0] != '\0') {
1581 free(tmpnew);
1582 }
1583 if (ret) {
1584 goto error;
1585 }
1586 break;
1587 }
1588 case LTTNG_CONSUMER32_UST:
1589 {
1590 char *tmpnew = NULL;
1591
1592 if (consumerd32_libdir[0] != '\0') {
1593 char *tmp;
1594 size_t tmplen;
1595
1596 tmp = getenv("LD_LIBRARY_PATH");
1597 if (!tmp) {
1598 tmp = "";
1599 }
1600 tmplen = strlen("LD_LIBRARY_PATH=")
1601 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1602 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1603 if (!tmpnew) {
1604 ret = -ENOMEM;
1605 goto error;
1606 }
1607 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1608 strcat(tmpnew, consumerd32_libdir);
1609 if (tmp[0] != '\0') {
1610 strcat(tmpnew, ":");
1611 strcat(tmpnew, tmp);
1612 }
1613 ret = putenv(tmpnew);
1614 if (ret) {
1615 ret = -errno;
1616 goto error;
1617 }
1618 }
1619 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1620 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1621 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1622 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1623 NULL);
1624 if (consumerd32_libdir[0] != '\0') {
1625 free(tmpnew);
1626 }
1627 if (ret) {
1628 goto error;
1629 }
1630 break;
1631 }
1632 default:
1633 perror("unknown consumer type");
1634 exit(EXIT_FAILURE);
1635 }
1636 if (errno != 0) {
1637 perror("kernel start consumer exec");
1638 }
1639 exit(EXIT_FAILURE);
1640 } else if (pid > 0) {
1641 ret = pid;
1642 } else {
1643 perror("start consumer fork");
1644 ret = -errno;
1645 }
1646 error:
1647 return ret;
1648 }
1649
1650 /*
1651 * Spawn the consumerd daemon and session daemon thread.
1652 */
1653 static int start_consumerd(struct consumer_data *consumer_data)
1654 {
1655 int ret;
1656
1657 pthread_mutex_lock(&consumer_data->pid_mutex);
1658 if (consumer_data->pid != 0) {
1659 pthread_mutex_unlock(&consumer_data->pid_mutex);
1660 goto end;
1661 }
1662
1663 ret = spawn_consumerd(consumer_data);
1664 if (ret < 0) {
1665 ERR("Spawning consumerd failed");
1666 pthread_mutex_unlock(&consumer_data->pid_mutex);
1667 goto error;
1668 }
1669
1670 /* Setting up the consumer_data pid */
1671 consumer_data->pid = ret;
1672 DBG2("Consumer pid %d", consumer_data->pid);
1673 pthread_mutex_unlock(&consumer_data->pid_mutex);
1674
1675 DBG2("Spawning consumer control thread");
1676 ret = spawn_consumer_thread(consumer_data);
1677 if (ret < 0) {
1678 ERR("Fatal error spawning consumer control thread");
1679 goto error;
1680 }
1681
1682 end:
1683 return 0;
1684
1685 error:
1686 return ret;
1687 }
1688
1689 /*
1690 * Check version of the lttng-modules.
1691 */
1692 static int validate_lttng_modules_version(void)
1693 {
1694 return kernel_validate_version(kernel_tracer_fd);
1695 }
1696
1697 /*
1698 * Setup necessary data for kernel tracer action.
1699 */
1700 static int init_kernel_tracer(void)
1701 {
1702 int ret;
1703
1704 /* Modprobe lttng kernel modules */
1705 ret = modprobe_lttng_control();
1706 if (ret < 0) {
1707 goto error;
1708 }
1709
1710 /* Open debugfs lttng */
1711 kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
1712 if (kernel_tracer_fd < 0) {
1713 DBG("Failed to open %s", module_proc_lttng);
1714 ret = -1;
1715 goto error_open;
1716 }
1717
1718 /* Validate kernel version */
1719 ret = validate_lttng_modules_version();
1720 if (ret < 0) {
1721 goto error_version;
1722 }
1723
1724 ret = modprobe_lttng_data();
1725 if (ret < 0) {
1726 goto error_modules;
1727 }
1728
1729 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1730 return 0;
1731
1732 error_version:
1733 modprobe_remove_lttng_control();
1734 close(kernel_tracer_fd);
1735 kernel_tracer_fd = 0;
1736 return LTTCOMM_KERN_VERSION;
1737
1738 error_modules:
1739 close(kernel_tracer_fd);
1740
1741 error_open:
1742 modprobe_remove_lttng_control();
1743
1744 error:
1745 WARN("No kernel tracer available");
1746 kernel_tracer_fd = 0;
1747 return LTTCOMM_KERN_NA;
1748 }
1749
1750 /*
1751 * Init tracing by creating trace directory and sending fds kernel consumer.
1752 */
1753 static int init_kernel_tracing(struct ltt_kernel_session *session)
1754 {
1755 int ret = 0;
1756
1757 if (session->consumer_fds_sent == 0) {
1758 /*
1759 * Assign default kernel consumer socket if no consumer assigned to the
1760 * kernel session. At this point, it's NOT suppose to be 0 but this is
1761 * an extra security check.
1762 */
1763 if (session->consumer_fd == 0) {
1764 session->consumer_fd = kconsumer_data.cmd_sock;
1765 }
1766
1767 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1768 if (ret < 0) {
1769 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1770 goto error;
1771 }
1772
1773 session->consumer_fds_sent = 1;
1774 }
1775
1776 error:
1777 return ret;
1778 }
1779
1780 /*
1781 * Create an UST session and add it to the session ust list.
1782 */
1783 static int create_ust_session(struct ltt_session *session,
1784 struct lttng_domain *domain)
1785 {
1786 struct ltt_ust_session *lus = NULL;
1787 int ret;
1788
1789 switch (domain->type) {
1790 case LTTNG_DOMAIN_UST:
1791 break;
1792 default:
1793 ret = LTTCOMM_UNKNOWN_DOMAIN;
1794 goto error;
1795 }
1796
1797 DBG("Creating UST session");
1798
1799 lus = trace_ust_create_session(session->path, session->id, domain);
1800 if (lus == NULL) {
1801 ret = LTTCOMM_UST_SESS_FAIL;
1802 goto error;
1803 }
1804
1805 ret = run_as_mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1806 session->uid, session->gid);
1807 if (ret < 0) {
1808 if (ret != -EEXIST) {
1809 ERR("Trace directory creation error");
1810 ret = LTTCOMM_UST_SESS_FAIL;
1811 goto error;
1812 }
1813 }
1814
1815 /* The domain type dictate different actions on session creation */
1816 switch (domain->type) {
1817 case LTTNG_DOMAIN_UST:
1818 /* No ustctl for the global UST domain */
1819 break;
1820 default:
1821 ERR("Unknown UST domain on create session %d", domain->type);
1822 goto error;
1823 }
1824 lus->uid = session->uid;
1825 lus->gid = session->gid;
1826 session->ust_session = lus;
1827
1828 return LTTCOMM_OK;
1829
1830 error:
1831 free(lus);
1832 return ret;
1833 }
1834
1835 /*
1836 * Create a kernel tracer session then create the default channel.
1837 */
1838 static int create_kernel_session(struct ltt_session *session)
1839 {
1840 int ret;
1841
1842 DBG("Creating kernel session");
1843
1844 ret = kernel_create_session(session, kernel_tracer_fd);
1845 if (ret < 0) {
1846 ret = LTTCOMM_KERN_SESS_FAIL;
1847 goto error;
1848 }
1849
1850 /* Set kernel consumer socket fd */
1851 if (kconsumer_data.cmd_sock) {
1852 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1853 }
1854
1855 ret = run_as_mkdir_recursive(session->kernel_session->trace_path,
1856 S_IRWXU | S_IRWXG, session->uid, session->gid);
1857 if (ret < 0) {
1858 if (ret != -EEXIST) {
1859 ERR("Trace directory creation error");
1860 goto error;
1861 }
1862 }
1863 session->kernel_session->uid = session->uid;
1864 session->kernel_session->gid = session->gid;
1865
1866 error:
1867 return ret;
1868 }
1869
1870 /*
1871 * Check if the UID or GID match the session. Root user has access to all
1872 * sessions.
1873 */
1874 static int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid)
1875 {
1876 if (uid != session->uid && gid != session->gid && uid != 0) {
1877 return 0;
1878 } else {
1879 return 1;
1880 }
1881 }
1882
1883 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
1884 {
1885 unsigned int i = 0;
1886 struct ltt_session *session;
1887
1888 DBG("Counting number of available session for UID %d GID %d",
1889 uid, gid);
1890 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1891 /*
1892 * Only list the sessions the user can control.
1893 */
1894 if (!session_access_ok(session, uid, gid)) {
1895 continue;
1896 }
1897 i++;
1898 }
1899 return i;
1900 }
1901
1902 /*
1903 * Using the session list, filled a lttng_session array to send back to the
1904 * client for session listing.
1905 *
1906 * The session list lock MUST be acquired before calling this function. Use
1907 * session_lock_list() and session_unlock_list().
1908 */
1909 static void list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
1910 gid_t gid)
1911 {
1912 unsigned int i = 0;
1913 struct ltt_session *session;
1914
1915 DBG("Getting all available session for UID %d GID %d",
1916 uid, gid);
1917 /*
1918 * Iterate over session list and append data after the control struct in
1919 * the buffer.
1920 */
1921 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1922 /*
1923 * Only list the sessions the user can control.
1924 */
1925 if (!session_access_ok(session, uid, gid)) {
1926 continue;
1927 }
1928 strncpy(sessions[i].path, session->path, PATH_MAX);
1929 sessions[i].path[PATH_MAX - 1] = '\0';
1930 strncpy(sessions[i].name, session->name, NAME_MAX);
1931 sessions[i].name[NAME_MAX - 1] = '\0';
1932 sessions[i].enabled = session->enabled;
1933 i++;
1934 }
1935 }
1936
1937 /*
1938 * Fill lttng_channel array of all channels.
1939 */
1940 static void list_lttng_channels(int domain, struct ltt_session *session,
1941 struct lttng_channel *channels)
1942 {
1943 int i = 0;
1944 struct ltt_kernel_channel *kchan;
1945
1946 DBG("Listing channels for session %s", session->name);
1947
1948 switch (domain) {
1949 case LTTNG_DOMAIN_KERNEL:
1950 /* Kernel channels */
1951 if (session->kernel_session != NULL) {
1952 cds_list_for_each_entry(kchan,
1953 &session->kernel_session->channel_list.head, list) {
1954 /* Copy lttng_channel struct to array */
1955 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
1956 channels[i].enabled = kchan->enabled;
1957 i++;
1958 }
1959 }
1960 break;
1961 case LTTNG_DOMAIN_UST:
1962 {
1963 struct lttng_ht_iter iter;
1964 struct ltt_ust_channel *uchan;
1965
1966 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
1967 &iter.iter, uchan, node.node) {
1968 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
1969 channels[i].attr.overwrite = uchan->attr.overwrite;
1970 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
1971 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
1972 channels[i].attr.switch_timer_interval =
1973 uchan->attr.switch_timer_interval;
1974 channels[i].attr.read_timer_interval =
1975 uchan->attr.read_timer_interval;
1976 channels[i].enabled = uchan->enabled;
1977 switch (uchan->attr.output) {
1978 case LTTNG_UST_MMAP:
1979 default:
1980 channels[i].attr.output = LTTNG_EVENT_MMAP;
1981 break;
1982 }
1983 i++;
1984 }
1985 break;
1986 }
1987 default:
1988 break;
1989 }
1990 }
1991
1992 /*
1993 * Create a list of ust global domain events.
1994 */
1995 static int list_lttng_ust_global_events(char *channel_name,
1996 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
1997 {
1998 int i = 0, ret = 0;
1999 unsigned int nb_event = 0;
2000 struct lttng_ht_iter iter;
2001 struct lttng_ht_node_str *node;
2002 struct ltt_ust_channel *uchan;
2003 struct ltt_ust_event *uevent;
2004 struct lttng_event *tmp;
2005
2006 DBG("Listing UST global events for channel %s", channel_name);
2007
2008 rcu_read_lock();
2009
2010 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2011 node = lttng_ht_iter_get_node_str(&iter);
2012 if (node == NULL) {
2013 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2014 goto error;
2015 }
2016
2017 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2018
2019 nb_event += lttng_ht_get_count(uchan->events);
2020
2021 if (nb_event == 0) {
2022 ret = nb_event;
2023 goto error;
2024 }
2025
2026 DBG3("Listing UST global %d events", nb_event);
2027
2028 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2029 if (tmp == NULL) {
2030 ret = -LTTCOMM_FATAL;
2031 goto error;
2032 }
2033
2034 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2035 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2036 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2037 tmp[i].enabled = uevent->enabled;
2038 switch (uevent->attr.instrumentation) {
2039 case LTTNG_UST_TRACEPOINT:
2040 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2041 break;
2042 case LTTNG_UST_PROBE:
2043 tmp[i].type = LTTNG_EVENT_PROBE;
2044 break;
2045 case LTTNG_UST_FUNCTION:
2046 tmp[i].type = LTTNG_EVENT_FUNCTION;
2047 break;
2048 }
2049 tmp[i].loglevel = uevent->attr.loglevel;
2050 switch (uevent->attr.loglevel_type) {
2051 case LTTNG_UST_LOGLEVEL_ALL:
2052 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2053 break;
2054 case LTTNG_UST_LOGLEVEL_RANGE:
2055 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
2056 break;
2057 case LTTNG_UST_LOGLEVEL_SINGLE:
2058 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
2059 break;
2060 }
2061 i++;
2062 }
2063
2064 ret = nb_event;
2065 *events = tmp;
2066
2067 error:
2068 rcu_read_unlock();
2069 return ret;
2070 }
2071
2072 /*
2073 * Fill lttng_event array of all kernel events in the channel.
2074 */
2075 static int list_lttng_kernel_events(char *channel_name,
2076 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2077 {
2078 int i = 0, ret;
2079 unsigned int nb_event;
2080 struct ltt_kernel_event *event;
2081 struct ltt_kernel_channel *kchan;
2082
2083 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2084 if (kchan == NULL) {
2085 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2086 goto error;
2087 }
2088
2089 nb_event = kchan->event_count;
2090
2091 DBG("Listing events for channel %s", kchan->channel->name);
2092
2093 if (nb_event == 0) {
2094 ret = nb_event;
2095 goto error;
2096 }
2097
2098 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2099 if (*events == NULL) {
2100 ret = LTTCOMM_FATAL;
2101 goto error;
2102 }
2103
2104 /* Kernel channels */
2105 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2106 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2107 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2108 (*events)[i].enabled = event->enabled;
2109 switch (event->event->instrumentation) {
2110 case LTTNG_KERNEL_TRACEPOINT:
2111 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2112 break;
2113 case LTTNG_KERNEL_KPROBE:
2114 case LTTNG_KERNEL_KRETPROBE:
2115 (*events)[i].type = LTTNG_EVENT_PROBE;
2116 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2117 sizeof(struct lttng_kernel_kprobe));
2118 break;
2119 case LTTNG_KERNEL_FUNCTION:
2120 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2121 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2122 sizeof(struct lttng_kernel_function));
2123 break;
2124 case LTTNG_KERNEL_NOOP:
2125 (*events)[i].type = LTTNG_EVENT_NOOP;
2126 break;
2127 case LTTNG_KERNEL_SYSCALL:
2128 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2129 break;
2130 case LTTNG_KERNEL_ALL:
2131 assert(0);
2132 break;
2133 }
2134 i++;
2135 }
2136
2137 return nb_event;
2138
2139 error:
2140 return ret;
2141 }
2142
2143 /*
2144 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2145 */
2146 static int cmd_disable_channel(struct ltt_session *session,
2147 int domain, char *channel_name)
2148 {
2149 int ret;
2150 struct ltt_ust_session *usess;
2151
2152 usess = session->ust_session;
2153
2154 switch (domain) {
2155 case LTTNG_DOMAIN_KERNEL:
2156 {
2157 ret = channel_kernel_disable(session->kernel_session,
2158 channel_name);
2159 if (ret != LTTCOMM_OK) {
2160 goto error;
2161 }
2162
2163 kernel_wait_quiescent(kernel_tracer_fd);
2164 break;
2165 }
2166 case LTTNG_DOMAIN_UST:
2167 {
2168 struct ltt_ust_channel *uchan;
2169 struct lttng_ht *chan_ht;
2170
2171 chan_ht = usess->domain_global.channels;
2172
2173 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2174 if (uchan == NULL) {
2175 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2176 goto error;
2177 }
2178
2179 ret = channel_ust_disable(usess, domain, uchan);
2180 if (ret != LTTCOMM_OK) {
2181 goto error;
2182 }
2183 break;
2184 }
2185 #if 0
2186 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2187 case LTTNG_DOMAIN_UST_EXEC_NAME:
2188 case LTTNG_DOMAIN_UST_PID:
2189 #endif
2190 default:
2191 ret = LTTCOMM_UNKNOWN_DOMAIN;
2192 goto error;
2193 }
2194
2195 ret = LTTCOMM_OK;
2196
2197 error:
2198 return ret;
2199 }
2200
2201 /*
2202 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2203 */
2204 static int cmd_enable_channel(struct ltt_session *session,
2205 int domain, struct lttng_channel *attr)
2206 {
2207 int ret;
2208 struct ltt_ust_session *usess = session->ust_session;
2209 struct lttng_ht *chan_ht;
2210
2211 DBG("Enabling channel %s for session %s", attr->name, session->name);
2212
2213 switch (domain) {
2214 case LTTNG_DOMAIN_KERNEL:
2215 {
2216 struct ltt_kernel_channel *kchan;
2217
2218 kchan = trace_kernel_get_channel_by_name(attr->name,
2219 session->kernel_session);
2220 if (kchan == NULL) {
2221 ret = channel_kernel_create(session->kernel_session,
2222 attr, kernel_poll_pipe[1]);
2223 } else {
2224 ret = channel_kernel_enable(session->kernel_session, kchan);
2225 }
2226
2227 if (ret != LTTCOMM_OK) {
2228 goto error;
2229 }
2230
2231 kernel_wait_quiescent(kernel_tracer_fd);
2232 break;
2233 }
2234 case LTTNG_DOMAIN_UST:
2235 {
2236 struct ltt_ust_channel *uchan;
2237
2238 chan_ht = usess->domain_global.channels;
2239
2240 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2241 if (uchan == NULL) {
2242 ret = channel_ust_create(usess, domain, attr);
2243 } else {
2244 ret = channel_ust_enable(usess, domain, uchan);
2245 }
2246 break;
2247 }
2248 #if 0
2249 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2250 case LTTNG_DOMAIN_UST_EXEC_NAME:
2251 case LTTNG_DOMAIN_UST_PID:
2252 #endif
2253 default:
2254 ret = LTTCOMM_UNKNOWN_DOMAIN;
2255 goto error;
2256 }
2257
2258 error:
2259 return ret;
2260 }
2261
2262 /*
2263 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2264 */
2265 static int cmd_disable_event(struct ltt_session *session, int domain,
2266 char *channel_name, char *event_name)
2267 {
2268 int ret;
2269
2270 switch (domain) {
2271 case LTTNG_DOMAIN_KERNEL:
2272 {
2273 struct ltt_kernel_channel *kchan;
2274 struct ltt_kernel_session *ksess;
2275
2276 ksess = session->kernel_session;
2277
2278 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2279 if (kchan == NULL) {
2280 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2281 goto error;
2282 }
2283
2284 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
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 struct ltt_ust_session *usess;
2296
2297 usess = session->ust_session;
2298
2299 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2300 channel_name);
2301 if (uchan == NULL) {
2302 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2303 goto error;
2304 }
2305
2306 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2307 if (ret != LTTCOMM_OK) {
2308 goto error;
2309 }
2310
2311 DBG3("Disable UST event %s in channel %s completed", event_name,
2312 channel_name);
2313 break;
2314 }
2315 #if 0
2316 case LTTNG_DOMAIN_UST_EXEC_NAME:
2317 case LTTNG_DOMAIN_UST_PID:
2318 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2319 #endif
2320 default:
2321 ret = LTTCOMM_UND;
2322 goto error;
2323 }
2324
2325 ret = LTTCOMM_OK;
2326
2327 error:
2328 return ret;
2329 }
2330
2331 /*
2332 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2333 */
2334 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2335 char *channel_name)
2336 {
2337 int ret;
2338
2339 switch (domain) {
2340 case LTTNG_DOMAIN_KERNEL:
2341 {
2342 struct ltt_kernel_session *ksess;
2343 struct ltt_kernel_channel *kchan;
2344
2345 ksess = session->kernel_session;
2346
2347 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2348 if (kchan == NULL) {
2349 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2350 goto error;
2351 }
2352
2353 ret = event_kernel_disable_all(ksess, kchan);
2354 if (ret != LTTCOMM_OK) {
2355 goto error;
2356 }
2357
2358 kernel_wait_quiescent(kernel_tracer_fd);
2359 break;
2360 }
2361 case LTTNG_DOMAIN_UST:
2362 {
2363 struct ltt_ust_session *usess;
2364 struct ltt_ust_channel *uchan;
2365
2366 usess = session->ust_session;
2367
2368 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2369 channel_name);
2370 if (uchan == NULL) {
2371 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2372 goto error;
2373 }
2374
2375 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2376 if (ret != 0) {
2377 goto error;
2378 }
2379
2380 DBG3("Disable all UST events in channel %s completed", channel_name);
2381
2382 break;
2383 }
2384 #if 0
2385 case LTTNG_DOMAIN_UST_EXEC_NAME:
2386 case LTTNG_DOMAIN_UST_PID:
2387 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2388 #endif
2389 default:
2390 ret = LTTCOMM_UND;
2391 goto error;
2392 }
2393
2394 ret = LTTCOMM_OK;
2395
2396 error:
2397 return ret;
2398 }
2399
2400 /*
2401 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2402 */
2403 static int cmd_add_context(struct ltt_session *session, int domain,
2404 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2405 {
2406 int ret;
2407
2408 switch (domain) {
2409 case LTTNG_DOMAIN_KERNEL:
2410 /* Add kernel context to kernel tracer */
2411 ret = context_kernel_add(session->kernel_session, ctx,
2412 event_name, channel_name);
2413 if (ret != LTTCOMM_OK) {
2414 goto error;
2415 }
2416 break;
2417 case LTTNG_DOMAIN_UST:
2418 {
2419 struct ltt_ust_session *usess = session->ust_session;
2420
2421 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2422 if (ret != LTTCOMM_OK) {
2423 goto error;
2424 }
2425 break;
2426 }
2427 #if 0
2428 case LTTNG_DOMAIN_UST_EXEC_NAME:
2429 case LTTNG_DOMAIN_UST_PID:
2430 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2431 #endif
2432 default:
2433 ret = LTTCOMM_UND;
2434 goto error;
2435 }
2436
2437 ret = LTTCOMM_OK;
2438
2439 error:
2440 return ret;
2441 }
2442
2443 /*
2444 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2445 */
2446 static int cmd_enable_event(struct ltt_session *session, int domain,
2447 char *channel_name, struct lttng_event *event)
2448 {
2449 int ret;
2450 struct lttng_channel *attr;
2451 struct ltt_ust_session *usess = session->ust_session;
2452
2453 switch (domain) {
2454 case LTTNG_DOMAIN_KERNEL:
2455 {
2456 struct ltt_kernel_channel *kchan;
2457
2458 kchan = trace_kernel_get_channel_by_name(channel_name,
2459 session->kernel_session);
2460 if (kchan == NULL) {
2461 attr = channel_new_default_attr(domain);
2462 if (attr == NULL) {
2463 ret = LTTCOMM_FATAL;
2464 goto error;
2465 }
2466 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2467
2468 /* This call will notify the kernel thread */
2469 ret = channel_kernel_create(session->kernel_session,
2470 attr, kernel_poll_pipe[1]);
2471 if (ret != LTTCOMM_OK) {
2472 free(attr);
2473 goto error;
2474 }
2475 free(attr);
2476 }
2477
2478 /* Get the newly created kernel channel pointer */
2479 kchan = trace_kernel_get_channel_by_name(channel_name,
2480 session->kernel_session);
2481 if (kchan == NULL) {
2482 /* This sould not happen... */
2483 ret = LTTCOMM_FATAL;
2484 goto error;
2485 }
2486
2487 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2488 event);
2489 if (ret != LTTCOMM_OK) {
2490 goto error;
2491 }
2492
2493 kernel_wait_quiescent(kernel_tracer_fd);
2494 break;
2495 }
2496 case LTTNG_DOMAIN_UST:
2497 {
2498 struct lttng_channel *attr;
2499 struct ltt_ust_channel *uchan;
2500
2501 /* Get channel from global UST domain */
2502 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2503 channel_name);
2504 if (uchan == NULL) {
2505 /* Create default channel */
2506 attr = channel_new_default_attr(domain);
2507 if (attr == NULL) {
2508 ret = LTTCOMM_FATAL;
2509 goto error;
2510 }
2511 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2512 attr->name[NAME_MAX - 1] = '\0';
2513
2514 ret = channel_ust_create(usess, domain, attr);
2515 if (ret != LTTCOMM_OK) {
2516 free(attr);
2517 goto error;
2518 }
2519 free(attr);
2520
2521 /* Get the newly created channel reference back */
2522 uchan = trace_ust_find_channel_by_name(
2523 usess->domain_global.channels, channel_name);
2524 if (uchan == NULL) {
2525 /* Something is really wrong */
2526 ret = LTTCOMM_FATAL;
2527 goto error;
2528 }
2529 }
2530
2531 /* At this point, the session and channel exist on the tracer */
2532 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2533 if (ret != LTTCOMM_OK) {
2534 goto error;
2535 }
2536 break;
2537 }
2538 #if 0
2539 case LTTNG_DOMAIN_UST_EXEC_NAME:
2540 case LTTNG_DOMAIN_UST_PID:
2541 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2542 #endif
2543 default:
2544 ret = LTTCOMM_UND;
2545 goto error;
2546 }
2547
2548 ret = LTTCOMM_OK;
2549
2550 error:
2551 return ret;
2552 }
2553
2554 /*
2555 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2556 */
2557 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2558 char *channel_name, int event_type)
2559 {
2560 int ret;
2561 struct ltt_kernel_channel *kchan;
2562
2563 switch (domain) {
2564 case LTTNG_DOMAIN_KERNEL:
2565 kchan = trace_kernel_get_channel_by_name(channel_name,
2566 session->kernel_session);
2567 if (kchan == NULL) {
2568 /* This call will notify the kernel thread */
2569 ret = channel_kernel_create(session->kernel_session, NULL,
2570 kernel_poll_pipe[1]);
2571 if (ret != LTTCOMM_OK) {
2572 goto error;
2573 }
2574
2575 /* Get the newly created kernel channel pointer */
2576 kchan = trace_kernel_get_channel_by_name(channel_name,
2577 session->kernel_session);
2578 if (kchan == NULL) {
2579 /* This sould not happen... */
2580 ret = LTTCOMM_FATAL;
2581 goto error;
2582 }
2583
2584 }
2585
2586 switch (event_type) {
2587 case LTTNG_EVENT_SYSCALL:
2588 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2589 kchan, kernel_tracer_fd);
2590 break;
2591 case LTTNG_EVENT_TRACEPOINT:
2592 /*
2593 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2594 * events already registered to the channel.
2595 */
2596 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2597 kchan, kernel_tracer_fd);
2598 break;
2599 case LTTNG_EVENT_ALL:
2600 /* Enable syscalls and tracepoints */
2601 ret = event_kernel_enable_all(session->kernel_session,
2602 kchan, kernel_tracer_fd);
2603 break;
2604 default:
2605 ret = LTTCOMM_KERN_ENABLE_FAIL;
2606 goto error;
2607 }
2608
2609 /* Manage return value */
2610 if (ret != LTTCOMM_OK) {
2611 goto error;
2612 }
2613
2614 kernel_wait_quiescent(kernel_tracer_fd);
2615 break;
2616 case LTTNG_DOMAIN_UST:
2617 {
2618 struct lttng_channel *attr;
2619 struct ltt_ust_channel *uchan;
2620 struct ltt_ust_session *usess = session->ust_session;
2621
2622 /* Get channel from global UST domain */
2623 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2624 channel_name);
2625 if (uchan == NULL) {
2626 /* Create default channel */
2627 attr = channel_new_default_attr(domain);
2628 if (attr == NULL) {
2629 ret = LTTCOMM_FATAL;
2630 goto error;
2631 }
2632 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2633 attr->name[NAME_MAX - 1] = '\0';
2634
2635 /* Use the internal command enable channel */
2636 ret = channel_ust_create(usess, domain, attr);
2637 if (ret != LTTCOMM_OK) {
2638 free(attr);
2639 goto error;
2640 }
2641 free(attr);
2642
2643 /* Get the newly created channel reference back */
2644 uchan = trace_ust_find_channel_by_name(
2645 usess->domain_global.channels, channel_name);
2646 if (uchan == NULL) {
2647 /* Something is really wrong */
2648 ret = LTTCOMM_FATAL;
2649 goto error;
2650 }
2651 }
2652
2653 /* At this point, the session and channel exist on the tracer */
2654
2655 switch (event_type) {
2656 case LTTNG_EVENT_ALL:
2657 case LTTNG_EVENT_TRACEPOINT:
2658 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2659 if (ret != LTTCOMM_OK) {
2660 goto error;
2661 }
2662 break;
2663 default:
2664 ret = LTTCOMM_UST_ENABLE_FAIL;
2665 goto error;
2666 }
2667
2668 /* Manage return value */
2669 if (ret != LTTCOMM_OK) {
2670 goto error;
2671 }
2672
2673 break;
2674 }
2675 #if 0
2676 case LTTNG_DOMAIN_UST_EXEC_NAME:
2677 case LTTNG_DOMAIN_UST_PID:
2678 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2679 #endif
2680 default:
2681 ret = LTTCOMM_UND;
2682 goto error;
2683 }
2684
2685 ret = LTTCOMM_OK;
2686
2687 error:
2688 return ret;
2689 }
2690
2691 /*
2692 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2693 */
2694 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2695 {
2696 int ret;
2697 ssize_t nb_events = 0;
2698
2699 switch (domain) {
2700 case LTTNG_DOMAIN_KERNEL:
2701 nb_events = kernel_list_events(kernel_tracer_fd, events);
2702 if (nb_events < 0) {
2703 ret = LTTCOMM_KERN_LIST_FAIL;
2704 goto error;
2705 }
2706 break;
2707 case LTTNG_DOMAIN_UST:
2708 nb_events = ust_app_list_events(events);
2709 if (nb_events < 0) {
2710 ret = LTTCOMM_UST_LIST_FAIL;
2711 goto error;
2712 }
2713 break;
2714 default:
2715 ret = LTTCOMM_UND;
2716 goto error;
2717 }
2718
2719 return nb_events;
2720
2721 error:
2722 /* Return negative value to differentiate return code */
2723 return -ret;
2724 }
2725
2726 /*
2727 * Command LTTNG_START_TRACE processed by the client thread.
2728 */
2729 static int cmd_start_trace(struct ltt_session *session)
2730 {
2731 int ret;
2732 struct ltt_kernel_session *ksession;
2733 struct ltt_ust_session *usess;
2734
2735 /* Short cut */
2736 ksession = session->kernel_session;
2737 usess = session->ust_session;
2738
2739 if (session->enabled) {
2740 ret = LTTCOMM_UST_START_FAIL;
2741 goto error;
2742 }
2743
2744 session->enabled = 1;
2745
2746 /* Kernel tracing */
2747 if (ksession != NULL) {
2748 struct ltt_kernel_channel *kchan;
2749
2750 /* Open kernel metadata */
2751 if (ksession->metadata == NULL) {
2752 ret = kernel_open_metadata(ksession, ksession->trace_path);
2753 if (ret < 0) {
2754 ret = LTTCOMM_KERN_META_FAIL;
2755 goto error;
2756 }
2757 }
2758
2759 /* Open kernel metadata stream */
2760 if (ksession->metadata_stream_fd == 0) {
2761 ret = kernel_open_metadata_stream(ksession);
2762 if (ret < 0) {
2763 ERR("Kernel create metadata stream failed");
2764 ret = LTTCOMM_KERN_STREAM_FAIL;
2765 goto error;
2766 }
2767 }
2768
2769 /* For each channel */
2770 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2771 if (kchan->stream_count == 0) {
2772 ret = kernel_open_channel_stream(kchan);
2773 if (ret < 0) {
2774 ret = LTTCOMM_KERN_STREAM_FAIL;
2775 goto error;
2776 }
2777 /* Update the stream global counter */
2778 ksession->stream_count_global += ret;
2779 }
2780 }
2781
2782 /* Setup kernel consumer socket and send fds to it */
2783 ret = init_kernel_tracing(ksession);
2784 if (ret < 0) {
2785 ret = LTTCOMM_KERN_START_FAIL;
2786 goto error;
2787 }
2788
2789 /* This start the kernel tracing */
2790 ret = kernel_start_session(ksession);
2791 if (ret < 0) {
2792 ret = LTTCOMM_KERN_START_FAIL;
2793 goto error;
2794 }
2795
2796 /* Quiescent wait after starting trace */
2797 kernel_wait_quiescent(kernel_tracer_fd);
2798 }
2799
2800 /* Flag session that trace should start automatically */
2801 if (usess) {
2802 usess->start_trace = 1;
2803
2804 ret = ust_app_start_trace_all(usess);
2805 if (ret < 0) {
2806 ret = LTTCOMM_UST_START_FAIL;
2807 goto error;
2808 }
2809 }
2810
2811 ret = LTTCOMM_OK;
2812
2813 error:
2814 return ret;
2815 }
2816
2817 /*
2818 * Command LTTNG_STOP_TRACE processed by the client thread.
2819 */
2820 static int cmd_stop_trace(struct ltt_session *session)
2821 {
2822 int ret;
2823 struct ltt_kernel_channel *kchan;
2824 struct ltt_kernel_session *ksession;
2825 struct ltt_ust_session *usess;
2826
2827 /* Short cut */
2828 ksession = session->kernel_session;
2829 usess = session->ust_session;
2830
2831 if (!session->enabled) {
2832 ret = LTTCOMM_UST_STOP_FAIL;
2833 goto error;
2834 }
2835
2836 session->enabled = 0;
2837
2838 /* Kernel tracer */
2839 if (ksession != NULL) {
2840 DBG("Stop kernel tracing");
2841
2842 /* Flush all buffers before stopping */
2843 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2844 if (ret < 0) {
2845 ERR("Kernel metadata flush failed");
2846 }
2847
2848 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2849 ret = kernel_flush_buffer(kchan);
2850 if (ret < 0) {
2851 ERR("Kernel flush buffer error");
2852 }
2853 }
2854
2855 ret = kernel_stop_session(ksession);
2856 if (ret < 0) {
2857 ret = LTTCOMM_KERN_STOP_FAIL;
2858 goto error;
2859 }
2860
2861 kernel_wait_quiescent(kernel_tracer_fd);
2862 }
2863
2864 if (usess) {
2865 usess->start_trace = 0;
2866
2867 ret = ust_app_stop_trace_all(usess);
2868 if (ret < 0) {
2869 ret = LTTCOMM_UST_STOP_FAIL;
2870 goto error;
2871 }
2872 }
2873
2874 ret = LTTCOMM_OK;
2875
2876 error:
2877 return ret;
2878 }
2879
2880 /*
2881 * Command LTTNG_CREATE_SESSION processed by the client thread.
2882 */
2883 static int cmd_create_session(char *name, char *path, lttng_sock_cred *creds)
2884 {
2885 int ret;
2886
2887 ret = session_create(name, path, LTTNG_SOCK_GET_UID_CRED(creds),
2888 LTTNG_SOCK_GET_GID_CRED(creds));
2889 if (ret != LTTCOMM_OK) {
2890 goto error;
2891 }
2892
2893 ret = LTTCOMM_OK;
2894
2895 error:
2896 return ret;
2897 }
2898
2899 /*
2900 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2901 */
2902 static int cmd_destroy_session(struct ltt_session *session, char *name)
2903 {
2904 int ret;
2905
2906 /* Clean kernel session teardown */
2907 teardown_kernel_session(session);
2908 /* UST session teardown */
2909 teardown_ust_session(session);
2910
2911 /*
2912 * Must notify the kernel thread here to update it's poll setin order
2913 * to remove the channel(s)' fd just destroyed.
2914 */
2915 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2916 if (ret < 0) {
2917 perror("write kernel poll pipe");
2918 }
2919
2920 ret = session_destroy(session);
2921
2922 return ret;
2923 }
2924
2925 /*
2926 * Command LTTNG_CALIBRATE processed by the client thread.
2927 */
2928 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2929 {
2930 int ret;
2931
2932 switch (domain) {
2933 case LTTNG_DOMAIN_KERNEL:
2934 {
2935 struct lttng_kernel_calibrate kcalibrate;
2936
2937 kcalibrate.type = calibrate->type;
2938 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2939 if (ret < 0) {
2940 ret = LTTCOMM_KERN_ENABLE_FAIL;
2941 goto error;
2942 }
2943 break;
2944 }
2945 case LTTNG_DOMAIN_UST:
2946 {
2947 struct lttng_ust_calibrate ucalibrate;
2948
2949 ucalibrate.type = calibrate->type;
2950 ret = ust_app_calibrate_glb(&ucalibrate);
2951 if (ret < 0) {
2952 ret = LTTCOMM_UST_CALIBRATE_FAIL;
2953 goto error;
2954 }
2955 break;
2956 }
2957 default:
2958 ret = LTTCOMM_UND;
2959 goto error;
2960 }
2961
2962 ret = LTTCOMM_OK;
2963
2964 error:
2965 return ret;
2966 }
2967
2968 /*
2969 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2970 */
2971 static int cmd_register_consumer(struct ltt_session *session, int domain,
2972 char *sock_path)
2973 {
2974 int ret, sock;
2975
2976 switch (domain) {
2977 case LTTNG_DOMAIN_KERNEL:
2978 /* Can't register a consumer if there is already one */
2979 if (session->kernel_session->consumer_fds_sent != 0) {
2980 ret = LTTCOMM_KERN_CONSUMER_FAIL;
2981 goto error;
2982 }
2983
2984 sock = lttcomm_connect_unix_sock(sock_path);
2985 if (sock < 0) {
2986 ret = LTTCOMM_CONNECT_FAIL;
2987 goto error;
2988 }
2989
2990 session->kernel_session->consumer_fd = sock;
2991 break;
2992 default:
2993 /* TODO: Userspace tracing */
2994 ret = LTTCOMM_UND;
2995 goto error;
2996 }
2997
2998 ret = LTTCOMM_OK;
2999
3000 error:
3001 return ret;
3002 }
3003
3004 /*
3005 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3006 */
3007 static ssize_t cmd_list_domains(struct ltt_session *session,
3008 struct lttng_domain **domains)
3009 {
3010 int ret, index = 0;
3011 ssize_t nb_dom = 0;
3012
3013 if (session->kernel_session != NULL) {
3014 DBG3("Listing domains found kernel domain");
3015 nb_dom++;
3016 }
3017
3018 if (session->ust_session != NULL) {
3019 DBG3("Listing domains found UST global domain");
3020 nb_dom++;
3021 }
3022
3023 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3024 if (*domains == NULL) {
3025 ret = -LTTCOMM_FATAL;
3026 goto error;
3027 }
3028
3029 if (session->kernel_session != NULL) {
3030 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3031 index++;
3032 }
3033
3034 if (session->ust_session != NULL) {
3035 (*domains)[index].type = LTTNG_DOMAIN_UST;
3036 index++;
3037 }
3038
3039 return nb_dom;
3040
3041 error:
3042 return ret;
3043 }
3044
3045 /*
3046 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3047 */
3048 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3049 struct lttng_channel **channels)
3050 {
3051 int ret;
3052 ssize_t nb_chan = 0;
3053
3054 switch (domain) {
3055 case LTTNG_DOMAIN_KERNEL:
3056 if (session->kernel_session != NULL) {
3057 nb_chan = session->kernel_session->channel_count;
3058 }
3059 DBG3("Number of kernel channels %zd", nb_chan);
3060 break;
3061 case LTTNG_DOMAIN_UST:
3062 if (session->ust_session != NULL) {
3063 nb_chan = lttng_ht_get_count(
3064 session->ust_session->domain_global.channels);
3065 }
3066 DBG3("Number of UST global channels %zd", nb_chan);
3067 break;
3068 default:
3069 *channels = NULL;
3070 ret = -LTTCOMM_UND;
3071 goto error;
3072 }
3073
3074 if (nb_chan > 0) {
3075 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3076 if (*channels == NULL) {
3077 ret = -LTTCOMM_FATAL;
3078 goto error;
3079 }
3080
3081 list_lttng_channels(domain, session, *channels);
3082 } else {
3083 *channels = NULL;
3084 }
3085
3086 return nb_chan;
3087
3088 error:
3089 return ret;
3090 }
3091
3092 /*
3093 * Command LTTNG_LIST_EVENTS processed by the client thread.
3094 */
3095 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3096 char *channel_name, struct lttng_event **events)
3097 {
3098 int ret = 0;
3099 ssize_t nb_event = 0;
3100
3101 switch (domain) {
3102 case LTTNG_DOMAIN_KERNEL:
3103 if (session->kernel_session != NULL) {
3104 nb_event = list_lttng_kernel_events(channel_name,
3105 session->kernel_session, events);
3106 }
3107 break;
3108 case LTTNG_DOMAIN_UST:
3109 {
3110 if (session->ust_session != NULL) {
3111 nb_event = list_lttng_ust_global_events(channel_name,
3112 &session->ust_session->domain_global, events);
3113 }
3114 break;
3115 }
3116 default:
3117 ret = -LTTCOMM_UND;
3118 goto error;
3119 }
3120
3121 ret = nb_event;
3122
3123 error:
3124 return ret;
3125 }
3126
3127 /*
3128 * Process the command requested by the lttng client within the command
3129 * context structure. This function make sure that the return structure (llm)
3130 * is set and ready for transmission before returning.
3131 *
3132 * Return any error encountered or 0 for success.
3133 */
3134 static int process_client_msg(struct command_ctx *cmd_ctx)
3135 {
3136 int ret = LTTCOMM_OK;
3137 int need_tracing_session = 1;
3138 int need_domain;
3139
3140 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3141
3142 switch (cmd_ctx->lsm->cmd_type) {
3143 case LTTNG_CREATE_SESSION:
3144 case LTTNG_DESTROY_SESSION:
3145 case LTTNG_LIST_SESSIONS:
3146 case LTTNG_LIST_DOMAINS:
3147 case LTTNG_START_TRACE:
3148 case LTTNG_STOP_TRACE:
3149 need_domain = 0;
3150 break;
3151 default:
3152 need_domain = 1;
3153 }
3154
3155 if (opt_no_kernel && need_domain
3156 && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
3157 ret = LTTCOMM_KERN_NA;
3158 goto error;
3159 }
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_CREATE_SESSION:
3185 case LTTNG_CALIBRATE:
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 if (!need_domain) {
3211 goto skip_domain;
3212 }
3213 /*
3214 * Check domain type for specific "pre-action".
3215 */
3216 switch (cmd_ctx->lsm->domain.type) {
3217 case LTTNG_DOMAIN_KERNEL:
3218 if (!is_root) {
3219 ret = LTTCOMM_KERN_NA;
3220 goto error;
3221 }
3222
3223 /* Kernel tracer check */
3224 if (kernel_tracer_fd == 0) {
3225 /* Basically, load kernel tracer modules */
3226 ret = init_kernel_tracer();
3227 if (ret != 0) {
3228 goto error;
3229 }
3230 }
3231
3232 /* Need a session for kernel command */
3233 if (need_tracing_session) {
3234 if (cmd_ctx->session->kernel_session == NULL) {
3235 ret = create_kernel_session(cmd_ctx->session);
3236 if (ret < 0) {
3237 ret = LTTCOMM_KERN_SESS_FAIL;
3238 goto error;
3239 }
3240 }
3241
3242 /* Start the kernel consumer daemon */
3243 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3244 if (kconsumer_data.pid == 0 &&
3245 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3246 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3247 ret = start_consumerd(&kconsumer_data);
3248 if (ret < 0) {
3249 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3250 goto error;
3251 }
3252 } else {
3253 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3254 }
3255 }
3256 break;
3257 case LTTNG_DOMAIN_UST:
3258 {
3259 if (need_tracing_session) {
3260 if (cmd_ctx->session->ust_session == NULL) {
3261 ret = create_ust_session(cmd_ctx->session,
3262 &cmd_ctx->lsm->domain);
3263 if (ret != LTTCOMM_OK) {
3264 goto error;