12322837e7f681038e0ed6fe54d2ac72e035668d
[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 .err_sock = -1,
104 .cmd_sock = -1,
105 };
106 static struct consumer_data ustconsumer64_data = {
107 .type = LTTNG_CONSUMER64_UST,
108 .err_unix_sock_path = DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
109 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
110 .err_sock = -1,
111 .cmd_sock = -1,
112 };
113 static struct consumer_data ustconsumer32_data = {
114 .type = LTTNG_CONSUMER32_UST,
115 .err_unix_sock_path = DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
116 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
117 .err_sock = -1,
118 .cmd_sock = -1,
119 };
120
121 static int dispatch_thread_exit;
122
123 /* Global application Unix socket path */
124 static char apps_unix_sock_path[PATH_MAX];
125 /* Global client Unix socket path */
126 static char client_unix_sock_path[PATH_MAX];
127 /* global wait shm path for UST */
128 static char wait_shm_path[PATH_MAX];
129
130 /* Sockets and FDs */
131 static int client_sock = -1;
132 static int apps_sock = -1;
133 static int kernel_tracer_fd = -1;
134 static int kernel_poll_pipe[2] = { -1, -1 };
135
136 /*
137 * Quit pipe for all threads. This permits a single cancellation point
138 * for all threads when receiving an event on the pipe.
139 */
140 static int thread_quit_pipe[2] = { -1, -1 };
141
142 /*
143 * This pipe is used to inform the thread managing application communication
144 * that a command is queued and ready to be processed.
145 */
146 static int apps_cmd_pipe[2] = { -1, -1 };
147
148 /* Pthread, Mutexes and Semaphores */
149 static pthread_t apps_thread;
150 static pthread_t reg_apps_thread;
151 static pthread_t client_thread;
152 static pthread_t kernel_thread;
153 static pthread_t dispatch_thread;
154
155
156 /*
157 * UST registration command queue. This queue is tied with a futex and uses a N
158 * wakers / 1 waiter implemented and detailed in futex.c/.h
159 *
160 * The thread_manage_apps and thread_dispatch_ust_registration interact with
161 * this queue and the wait/wake scheme.
162 */
163 static struct ust_cmd_queue ust_cmd_queue;
164
165 /*
166 * Pointer initialized before thread creation.
167 *
168 * This points to the tracing session list containing the session count and a
169 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
170 * MUST NOT be taken if you call a public function in session.c.
171 *
172 * The lock is nested inside the structure: session_list_ptr->lock. Please use
173 * session_lock_list and session_unlock_list for lock acquisition.
174 */
175 static struct ltt_session_list *session_list_ptr;
176
177 int ust_consumerd64_fd = -1;
178 int ust_consumerd32_fd = -1;
179
180 static const char *consumerd32_bin = CONFIG_CONSUMERD32_BIN;
181 static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
182 static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
183 static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
184
185 static
186 void setup_consumerd_path(void)
187 {
188 const char *bin, *libdir;
189
190 /*
191 * Allow INSTALL_BIN_PATH to be used as a target path for the
192 * native architecture size consumer if CONFIG_CONSUMER*_PATH
193 * has not been defined.
194 */
195 #if (CAA_BITS_PER_LONG == 32)
196 if (!consumerd32_bin[0]) {
197 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
198 }
199 if (!consumerd32_libdir[0]) {
200 consumerd32_libdir = INSTALL_LIB_PATH;
201 }
202 #elif (CAA_BITS_PER_LONG == 64)
203 if (!consumerd64_bin[0]) {
204 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
205 }
206 if (!consumerd64_libdir[0]) {
207 consumerd64_libdir = INSTALL_LIB_PATH;
208 }
209 #else
210 #error "Unknown bitness"
211 #endif
212
213 /*
214 * runtime env. var. overrides the build default.
215 */
216 bin = getenv("LTTNG_CONSUMERD32_BIN");
217 if (bin) {
218 consumerd32_bin = bin;
219 }
220 bin = getenv("LTTNG_CONSUMERD64_BIN");
221 if (bin) {
222 consumerd64_bin = bin;
223 }
224 libdir = getenv("LTTNG_CONSUMERD32_LIBDIR");
225 if (libdir) {
226 consumerd32_libdir = libdir;
227 }
228 libdir = getenv("LTTNG_CONSUMERD64_LIBDIR");
229 if (libdir) {
230 consumerd64_libdir = libdir;
231 }
232 }
233
234 /*
235 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
236 */
237 static int create_thread_poll_set(struct lttng_poll_event *events,
238 unsigned int size)
239 {
240 int ret;
241
242 if (events == NULL || size == 0) {
243 ret = -1;
244 goto error;
245 }
246
247 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
248 if (ret < 0) {
249 goto error;
250 }
251
252 /* Add quit pipe */
253 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
254 if (ret < 0) {
255 goto error;
256 }
257
258 return 0;
259
260 error:
261 return ret;
262 }
263
264 /*
265 * Check if the thread quit pipe was triggered.
266 *
267 * Return 1 if it was triggered else 0;
268 */
269 static int check_thread_quit_pipe(int fd, uint32_t events)
270 {
271 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
272 return 1;
273 }
274
275 return 0;
276 }
277
278 /*
279 * Return group ID of the tracing group or -1 if not found.
280 */
281 static gid_t allowed_group(void)
282 {
283 struct group *grp;
284
285 if (opt_tracing_group) {
286 grp = getgrnam(opt_tracing_group);
287 } else {
288 grp = getgrnam(default_tracing_group);
289 }
290 if (!grp) {
291 return -1;
292 } else {
293 return grp->gr_gid;
294 }
295 }
296
297 /*
298 * Init thread quit pipe.
299 *
300 * Return -1 on error or 0 if all pipes are created.
301 */
302 static int init_thread_quit_pipe(void)
303 {
304 int ret, i;
305
306 ret = pipe(thread_quit_pipe);
307 if (ret < 0) {
308 PERROR("thread quit pipe");
309 goto error;
310 }
311
312 for (i = 0; i < 2; i++) {
313 ret = fcntl(thread_quit_pipe[i], F_SETFD, FD_CLOEXEC);
314 if (ret < 0) {
315 PERROR("fcntl");
316 goto error;
317 }
318 }
319
320 error:
321 return ret;
322 }
323
324 /*
325 * Complete teardown of a kernel session. This free all data structure related
326 * to a kernel session and update counter.
327 */
328 static void teardown_kernel_session(struct ltt_session *session)
329 {
330 if (!session->kernel_session) {
331 DBG3("No kernel session when tearing down session");
332 return;
333 }
334
335 DBG("Tearing down kernel session");
336
337 /*
338 * If a custom kernel consumer was registered, close the socket before
339 * tearing down the complete kernel session structure
340 */
341 if (kconsumer_data.cmd_sock >= 0 &&
342 session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
343 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
344 }
345
346 trace_kernel_destroy_session(session->kernel_session);
347 }
348
349 /*
350 * Complete teardown of all UST sessions. This will free everything on his path
351 * and destroy the core essence of all ust sessions :)
352 */
353 static void teardown_ust_session(struct ltt_session *session)
354 {
355 int ret;
356
357 if (!session->ust_session) {
358 DBG3("No UST session when tearing down session");
359 return;
360 }
361
362 DBG("Tearing down UST session(s)");
363
364 ret = ust_app_destroy_trace_all(session->ust_session);
365 if (ret) {
366 ERR("Error in ust_app_destroy_trace_all");
367 }
368
369 trace_ust_destroy_session(session->ust_session);
370 }
371
372 /*
373 * Stop all threads by closing the thread quit pipe.
374 */
375 static void stop_threads(void)
376 {
377 int ret;
378
379 /* Stopping all threads */
380 DBG("Terminating all threads");
381 ret = notify_thread_pipe(thread_quit_pipe[1]);
382 if (ret < 0) {
383 ERR("write error on thread quit pipe");
384 }
385
386 /* Dispatch thread */
387 dispatch_thread_exit = 1;
388 futex_nto1_wake(&ust_cmd_queue.futex);
389 }
390
391 /*
392 * Cleanup the daemon
393 */
394 static void cleanup(void)
395 {
396 int ret, i;
397 char *cmd;
398 struct ltt_session *sess, *stmp;
399
400 DBG("Cleaning up");
401
402 DBG("Removing %s directory", rundir);
403 ret = asprintf(&cmd, "rm -rf %s", rundir);
404 if (ret < 0) {
405 ERR("asprintf failed. Something is really wrong!");
406 }
407
408 /* Remove lttng run directory */
409 ret = system(cmd);
410 if (ret < 0) {
411 ERR("Unable to clean %s", rundir);
412 }
413 free(cmd);
414
415 DBG("Cleaning up all sessions");
416
417 /* Destroy session list mutex */
418 if (session_list_ptr != NULL) {
419 pthread_mutex_destroy(&session_list_ptr->lock);
420
421 /* Cleanup ALL session */
422 cds_list_for_each_entry_safe(sess, stmp,
423 &session_list_ptr->head, list) {
424 teardown_kernel_session(sess);
425 teardown_ust_session(sess);
426 free(sess);
427 }
428 }
429
430 DBG("Closing all UST sockets");
431 ust_app_clean_list();
432
433 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
434
435 if (is_root && !opt_no_kernel) {
436 DBG2("Closing kernel fd");
437 if (kernel_tracer_fd >= 0) {
438 ret = close(kernel_tracer_fd);
439 if (ret) {
440 PERROR("close");
441 }
442 }
443 DBG("Unloading kernel modules");
444 modprobe_remove_lttng_all();
445 }
446
447 /*
448 * Closing all pipes used for communication between threads.
449 */
450 for (i = 0; i < 2; i++) {
451 if (kernel_poll_pipe[i] >= 0) {
452 ret = close(kernel_poll_pipe[i]);
453 if (ret) {
454 PERROR("close");
455 }
456
457 }
458 }
459 for (i = 0; i < 2; i++) {
460 if (thread_quit_pipe[i] >= 0) {
461 ret = close(thread_quit_pipe[i]);
462 if (ret) {
463 PERROR("close");
464 }
465 }
466 }
467 for (i = 0; i < 2; i++) {
468 if (apps_cmd_pipe[i] >= 0) {
469 ret = close(apps_cmd_pipe[i]);
470 if (ret) {
471 PERROR("close");
472 }
473 }
474 }
475
476 /* <fun> */
477 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
478 "Matthew, BEET driven development works!%c[%dm",
479 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
480 /* </fun> */
481 }
482
483 /*
484 * Send data on a unix socket using the liblttsessiondcomm API.
485 *
486 * Return lttcomm error code.
487 */
488 static int send_unix_sock(int sock, void *buf, size_t len)
489 {
490 /* Check valid length */
491 if (len <= 0) {
492 return -1;
493 }
494
495 return lttcomm_send_unix_sock(sock, buf, len);
496 }
497
498 /*
499 * Free memory of a command context structure.
500 */
501 static void clean_command_ctx(struct command_ctx **cmd_ctx)
502 {
503 DBG("Clean command context structure");
504 if (*cmd_ctx) {
505 if ((*cmd_ctx)->llm) {
506 free((*cmd_ctx)->llm);
507 }
508 if ((*cmd_ctx)->lsm) {
509 free((*cmd_ctx)->lsm);
510 }
511 free(*cmd_ctx);
512 *cmd_ctx = NULL;
513 }
514 }
515
516 /*
517 * Send all stream fds of kernel channel to the consumer.
518 */
519 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
520 int sock, struct ltt_kernel_channel *channel,
521 uid_t uid, gid_t gid)
522 {
523 int ret;
524 struct ltt_kernel_stream *stream;
525 struct lttcomm_consumer_msg lkm;
526
527 DBG("Sending streams of channel %s to kernel consumer",
528 channel->channel->name);
529
530 /* Send channel */
531 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
532 lkm.u.channel.channel_key = channel->fd;
533 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
534 lkm.u.channel.mmap_len = 0; /* for kernel */
535 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
536 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
537 if (ret < 0) {
538 PERROR("send consumer channel");
539 goto error;
540 }
541
542 /* Send streams */
543 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
544 if (!stream->fd) {
545 continue;
546 }
547 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
548 lkm.u.stream.channel_key = channel->fd;
549 lkm.u.stream.stream_key = stream->fd;
550 lkm.u.stream.state = stream->state;
551 lkm.u.stream.output = channel->channel->attr.output;
552 lkm.u.stream.mmap_len = 0; /* for kernel */
553 lkm.u.stream.uid = uid;
554 lkm.u.stream.gid = gid;
555 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
556 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
557 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
558 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
559 if (ret < 0) {
560 PERROR("send consumer stream");
561 goto error;
562 }
563 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
564 if (ret < 0) {
565 PERROR("send consumer stream ancillary data");
566 goto error;
567 }
568 }
569
570 DBG("consumer channel streams sent");
571
572 return 0;
573
574 error:
575 return ret;
576 }
577
578 /*
579 * Send all stream fds of the kernel session to the consumer.
580 */
581 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
582 struct ltt_kernel_session *session)
583 {
584 int ret;
585 struct ltt_kernel_channel *chan;
586 struct lttcomm_consumer_msg lkm;
587 int sock = session->consumer_fd;
588
589 DBG("Sending metadata stream fd");
590
591 /* Extra protection. It's NOT supposed to be set to -1 at this point */
592 if (session->consumer_fd < 0) {
593 session->consumer_fd = consumer_data->cmd_sock;
594 }
595
596 if (session->metadata_stream_fd >= 0) {
597 /* Send metadata channel fd */
598 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
599 lkm.u.channel.channel_key = session->metadata->fd;
600 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
601 lkm.u.channel.mmap_len = 0; /* for kernel */
602 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
603 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
604 if (ret < 0) {
605 PERROR("send consumer channel");
606 goto error;
607 }
608
609 /* Send metadata stream fd */
610 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
611 lkm.u.stream.channel_key = session->metadata->fd;
612 lkm.u.stream.stream_key = session->metadata_stream_fd;
613 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
614 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
615 lkm.u.stream.mmap_len = 0; /* for kernel */
616 lkm.u.stream.uid = session->uid;
617 lkm.u.stream.gid = session->gid;
618 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
619 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
620 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
621 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
622 if (ret < 0) {
623 PERROR("send consumer stream");
624 goto error;
625 }
626 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
627 if (ret < 0) {
628 PERROR("send consumer stream");
629 goto error;
630 }
631 }
632
633 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
634 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
635 session->uid, session->gid);
636 if (ret < 0) {
637 goto error;
638 }
639 }
640
641 DBG("consumer fds (metadata and channel streams) sent");
642
643 return 0;
644
645 error:
646 return ret;
647 }
648
649 /*
650 * Notify UST applications using the shm mmap futex.
651 */
652 static int notify_ust_apps(int active)
653 {
654 char *wait_shm_mmap;
655
656 DBG("Notifying applications of session daemon state: %d", active);
657
658 /* See shm.c for this call implying mmap, shm and futex calls */
659 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
660 if (wait_shm_mmap == NULL) {
661 goto error;
662 }
663
664 /* Wake waiting process */
665 futex_wait_update((int32_t *) wait_shm_mmap, active);
666
667 /* Apps notified successfully */
668 return 0;
669
670 error:
671 return -1;
672 }
673
674 /*
675 * Setup the outgoing data buffer for the response (llm) by allocating the
676 * right amount of memory and copying the original information from the lsm
677 * structure.
678 *
679 * Return total size of the buffer pointed by buf.
680 */
681 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
682 {
683 int ret, buf_size;
684
685 buf_size = size;
686
687 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
688 if (cmd_ctx->llm == NULL) {
689 PERROR("zmalloc");
690 ret = -ENOMEM;
691 goto error;
692 }
693
694 /* Copy common data */
695 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
696 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
697
698 cmd_ctx->llm->data_size = size;
699 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
700
701 return buf_size;
702
703 error:
704 return ret;
705 }
706
707 /*
708 * Update the kernel poll set of all channel fd available over all tracing
709 * session. Add the wakeup pipe at the end of the set.
710 */
711 static int update_kernel_poll(struct lttng_poll_event *events)
712 {
713 int ret;
714 struct ltt_session *session;
715 struct ltt_kernel_channel *channel;
716
717 DBG("Updating kernel poll set");
718
719 session_lock_list();
720 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
721 session_lock(session);
722 if (session->kernel_session == NULL) {
723 session_unlock(session);
724 continue;
725 }
726
727 cds_list_for_each_entry(channel,
728 &session->kernel_session->channel_list.head, list) {
729 /* Add channel fd to the kernel poll set */
730 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
731 if (ret < 0) {
732 session_unlock(session);
733 goto error;
734 }
735 DBG("Channel fd %d added to kernel set", channel->fd);
736 }
737 session_unlock(session);
738 }
739 session_unlock_list();
740
741 return 0;
742
743 error:
744 session_unlock_list();
745 return -1;
746 }
747
748 /*
749 * Find the channel fd from 'fd' over all tracing session. When found, check
750 * for new channel stream and send those stream fds to the kernel consumer.
751 *
752 * Useful for CPU hotplug feature.
753 */
754 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
755 {
756 int ret = 0;
757 struct ltt_session *session;
758 struct ltt_kernel_channel *channel;
759
760 DBG("Updating kernel streams for channel fd %d", fd);
761
762 session_lock_list();
763 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
764 session_lock(session);
765 if (session->kernel_session == NULL) {
766 session_unlock(session);
767 continue;
768 }
769
770 /* This is not suppose to be -1 but this is an extra security check */
771 if (session->kernel_session->consumer_fd < 0) {
772 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
773 }
774
775 cds_list_for_each_entry(channel,
776 &session->kernel_session->channel_list.head, list) {
777 if (channel->fd == fd) {
778 DBG("Channel found, updating kernel streams");
779 ret = kernel_open_channel_stream(channel);
780 if (ret < 0) {
781 goto error;
782 }
783
784 /*
785 * Have we already sent fds to the consumer? If yes, it means
786 * that tracing is started so it is safe to send our updated
787 * stream fds.
788 */
789 if (session->kernel_session->consumer_fds_sent == 1) {
790 ret = send_kconsumer_channel_streams(consumer_data,
791 session->kernel_session->consumer_fd, channel,
792 session->uid, session->gid);
793 if (ret < 0) {
794 goto error;
795 }
796 }
797 goto error;
798 }
799 }
800 session_unlock(session);
801 }
802 session_unlock_list();
803 return ret;
804
805 error:
806 session_unlock(session);
807 session_unlock_list();
808 return ret;
809 }
810
811 /*
812 * For each tracing session, update newly registered apps.
813 */
814 static void update_ust_app(int app_sock)
815 {
816 struct ltt_session *sess, *stmp;
817
818 session_lock_list();
819
820 /* For all tracing session(s) */
821 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
822 session_lock(sess);
823 if (sess->ust_session) {
824 ust_app_global_update(sess->ust_session, app_sock);
825 }
826 session_unlock(sess);
827 }
828
829 session_unlock_list();
830 }
831
832 /*
833 * This thread manage event coming from the kernel.
834 *
835 * Features supported in this thread:
836 * -) CPU Hotplug
837 */
838 static void *thread_manage_kernel(void *data)
839 {
840 int ret, i, pollfd, update_poll_flag = 1;
841 uint32_t revents, nb_fd;
842 char tmp;
843 struct lttng_poll_event events;
844
845 DBG("Thread manage kernel started");
846
847 ret = create_thread_poll_set(&events, 2);
848 if (ret < 0) {
849 goto error_poll_create;
850 }
851
852 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
853 if (ret < 0) {
854 goto error;
855 }
856
857 while (1) {
858 if (update_poll_flag == 1) {
859 /*
860 * Reset number of fd in the poll set. Always 2 since there is the thread
861 * quit pipe and the kernel pipe.
862 */
863 events.nb_fd = 2;
864
865 ret = update_kernel_poll(&events);
866 if (ret < 0) {
867 goto error;
868 }
869 update_poll_flag = 0;
870 }
871
872 nb_fd = LTTNG_POLL_GETNB(&events);
873
874 DBG("Thread kernel polling on %d fds", nb_fd);
875
876 /* Zeroed the poll events */
877 lttng_poll_reset(&events);
878
879 /* Poll infinite value of time */
880 restart:
881 ret = lttng_poll_wait(&events, -1);
882 if (ret < 0) {
883 /*
884 * Restart interrupted system call.
885 */
886 if (errno == EINTR) {
887 goto restart;
888 }
889 goto error;
890 } else if (ret == 0) {
891 /* Should not happen since timeout is infinite */
892 ERR("Return value of poll is 0 with an infinite timeout.\n"
893 "This should not have happened! Continuing...");
894 continue;
895 }
896
897 for (i = 0; i < nb_fd; i++) {
898 /* Fetch once the poll data */
899 revents = LTTNG_POLL_GETEV(&events, i);
900 pollfd = LTTNG_POLL_GETFD(&events, i);
901
902 /* Thread quit pipe has been closed. Killing thread. */
903 ret = check_thread_quit_pipe(pollfd, revents);
904 if (ret) {
905 goto error;
906 }
907
908 /* Check for data on kernel pipe */
909 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
910 ret = read(kernel_poll_pipe[0], &tmp, 1);
911 update_poll_flag = 1;
912 continue;
913 } else {
914 /*
915 * New CPU detected by the kernel. Adding kernel stream to
916 * kernel session and updating the kernel consumer
917 */
918 if (revents & LPOLLIN) {
919 ret = update_kernel_stream(&kconsumer_data, pollfd);
920 if (ret < 0) {
921 continue;
922 }
923 break;
924 /*
925 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
926 * and unregister kernel stream at this point.
927 */
928 }
929 }
930 }
931 }
932
933 error:
934 lttng_poll_clean(&events);
935 error_poll_create:
936 DBG("Kernel thread dying");
937 return NULL;
938 }
939
940 /*
941 * This thread manage the consumer error sent back to the session daemon.
942 */
943 static void *thread_manage_consumer(void *data)
944 {
945 int sock = -1, i, ret, pollfd;
946 uint32_t revents, nb_fd;
947 enum lttcomm_return_code code;
948 struct lttng_poll_event events;
949 struct consumer_data *consumer_data = data;
950
951 DBG("[thread] Manage consumer started");
952
953 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
954 if (ret < 0) {
955 goto error_listen;
956 }
957
958 /*
959 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
960 * Nothing more will be added to this poll set.
961 */
962 ret = create_thread_poll_set(&events, 2);
963 if (ret < 0) {
964 goto error_poll;
965 }
966
967 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
968 if (ret < 0) {
969 goto error;
970 }
971
972 nb_fd = LTTNG_POLL_GETNB(&events);
973
974 /* Inifinite blocking call, waiting for transmission */
975 restart:
976 ret = lttng_poll_wait(&events, -1);
977 if (ret < 0) {
978 /*
979 * Restart interrupted system call.
980 */
981 if (errno == EINTR) {
982 goto restart;
983 }
984 goto error;
985 }
986
987 for (i = 0; i < nb_fd; i++) {
988 /* Fetch once the poll data */
989 revents = LTTNG_POLL_GETEV(&events, i);
990 pollfd = LTTNG_POLL_GETFD(&events, i);
991
992 /* Thread quit pipe has been closed. Killing thread. */
993 ret = check_thread_quit_pipe(pollfd, revents);
994 if (ret) {
995 goto error;
996 }
997
998 /* Event on the registration socket */
999 if (pollfd == consumer_data->err_sock) {
1000 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1001 ERR("consumer err socket poll error");
1002 goto error;
1003 }
1004 }
1005 }
1006
1007 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
1008 if (sock < 0) {
1009 goto error;
1010 }
1011
1012 DBG2("Receiving code from consumer err_sock");
1013
1014 /* Getting status code from kconsumerd */
1015 ret = lttcomm_recv_unix_sock(sock, &code,
1016 sizeof(enum lttcomm_return_code));
1017 if (ret <= 0) {
1018 goto error;
1019 }
1020
1021 if (code == CONSUMERD_COMMAND_SOCK_READY) {
1022 consumer_data->cmd_sock =
1023 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
1024 if (consumer_data->cmd_sock < 0) {
1025 sem_post(&consumer_data->sem);
1026 PERROR("consumer connect");
1027 goto error;
1028 }
1029 /* Signal condition to tell that the kconsumerd is ready */
1030 sem_post(&consumer_data->sem);
1031 DBG("consumer command socket ready");
1032 } else {
1033 ERR("consumer error when waiting for SOCK_READY : %s",
1034 lttcomm_get_readable_code(-code));
1035 goto error;
1036 }
1037
1038 /* Remove the kconsumerd error sock since we've established a connexion */
1039 ret = lttng_poll_del(&events, consumer_data->err_sock);
1040 if (ret < 0) {
1041 goto error;
1042 }
1043
1044 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1045 if (ret < 0) {
1046 goto error;
1047 }
1048
1049 /* Update number of fd */
1050 nb_fd = LTTNG_POLL_GETNB(&events);
1051
1052 /* Inifinite blocking call, waiting for transmission */
1053 restart_poll:
1054 ret = lttng_poll_wait(&events, -1);
1055 if (ret < 0) {
1056 /*
1057 * Restart interrupted system call.
1058 */
1059 if (errno == EINTR) {
1060 goto restart_poll;
1061 }
1062 goto error;
1063 }
1064
1065 for (i = 0; i < nb_fd; i++) {
1066 /* Fetch once the poll data */
1067 revents = LTTNG_POLL_GETEV(&events, i);
1068 pollfd = LTTNG_POLL_GETFD(&events, i);
1069
1070 /* Thread quit pipe has been closed. Killing thread. */
1071 ret = check_thread_quit_pipe(pollfd, revents);
1072 if (ret) {
1073 goto error;
1074 }
1075
1076 /* Event on the kconsumerd socket */
1077 if (pollfd == sock) {
1078 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1079 ERR("consumer err socket second poll error");
1080 goto error;
1081 }
1082 }
1083 }
1084
1085 /* Wait for any kconsumerd error */
1086 ret = lttcomm_recv_unix_sock(sock, &code,
1087 sizeof(enum lttcomm_return_code));
1088 if (ret <= 0) {
1089 ERR("consumer closed the command socket");
1090 goto error;
1091 }
1092
1093 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1094
1095 error:
1096 if (consumer_data->err_sock >= 0) {
1097 ret = close(consumer_data->err_sock);
1098 if (ret) {
1099 PERROR("close");
1100 }
1101 }
1102 if (consumer_data->cmd_sock >= 0) {
1103 ret = close(consumer_data->cmd_sock);
1104 if (ret) {
1105 PERROR("close");
1106 }
1107 }
1108 if (sock >= 0) {
1109 ret = close(sock);
1110 if (ret) {
1111 PERROR("close");
1112 }
1113 }
1114
1115 unlink(consumer_data->err_unix_sock_path);
1116 unlink(consumer_data->cmd_unix_sock_path);
1117 consumer_data->pid = 0;
1118
1119 lttng_poll_clean(&events);
1120 error_poll:
1121 error_listen:
1122 DBG("consumer thread cleanup completed");
1123
1124 return NULL;
1125 }
1126
1127 /*
1128 * This thread manage application communication.
1129 */
1130 static void *thread_manage_apps(void *data)
1131 {
1132 int i, ret, pollfd;
1133 uint32_t revents, nb_fd;
1134 struct ust_command ust_cmd;
1135 struct lttng_poll_event events;
1136
1137 DBG("[thread] Manage application started");
1138
1139 rcu_register_thread();
1140 rcu_thread_online();
1141
1142 ret = create_thread_poll_set(&events, 2);
1143 if (ret < 0) {
1144 goto error_poll_create;
1145 }
1146
1147 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1148 if (ret < 0) {
1149 goto error;
1150 }
1151
1152 while (1) {
1153 /* Zeroed the events structure */
1154 lttng_poll_reset(&events);
1155
1156 nb_fd = LTTNG_POLL_GETNB(&events);
1157
1158 DBG("Apps thread polling on %d fds", nb_fd);
1159
1160 /* Inifinite blocking call, waiting for transmission */
1161 restart:
1162 ret = lttng_poll_wait(&events, -1);
1163 if (ret < 0) {
1164 /*
1165 * Restart interrupted system call.
1166 */
1167 if (errno == EINTR) {
1168 goto restart;
1169 }
1170 goto error;
1171 }
1172
1173 for (i = 0; i < nb_fd; i++) {
1174 /* Fetch once the poll data */
1175 revents = LTTNG_POLL_GETEV(&events, i);
1176 pollfd = LTTNG_POLL_GETFD(&events, i);
1177
1178 /* Thread quit pipe has been closed. Killing thread. */
1179 ret = check_thread_quit_pipe(pollfd, revents);
1180 if (ret) {
1181 goto error;
1182 }
1183
1184 /* Inspect the apps cmd pipe */
1185 if (pollfd == apps_cmd_pipe[0]) {
1186 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1187 ERR("Apps command pipe error");
1188 goto error;
1189 } else if (revents & LPOLLIN) {
1190 /* Empty pipe */
1191 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1192 if (ret < 0 || ret < sizeof(ust_cmd)) {
1193 PERROR("read apps cmd pipe");
1194 goto error;
1195 }
1196
1197 /* Register applicaton to the session daemon */
1198 ret = ust_app_register(&ust_cmd.reg_msg,
1199 ust_cmd.sock);
1200 if (ret == -ENOMEM) {
1201 goto error;
1202 } else if (ret < 0) {
1203 break;
1204 }
1205
1206 /*
1207 * Validate UST version compatibility.
1208 */
1209 ret = ust_app_validate_version(ust_cmd.sock);
1210 if (ret >= 0) {
1211 /*
1212 * Add channel(s) and event(s) to newly registered apps
1213 * from lttng global UST domain.
1214 */
1215 update_ust_app(ust_cmd.sock);
1216 }
1217
1218 ret = ust_app_register_done(ust_cmd.sock);
1219 if (ret < 0) {
1220 /*
1221 * If the registration is not possible, we simply
1222 * unregister the apps and continue
1223 */
1224 ust_app_unregister(ust_cmd.sock);
1225 } else {
1226 /*
1227 * We just need here to monitor the close of the UST
1228 * socket and poll set monitor those by default.
1229 * Listen on POLLIN (even if we never expect any
1230 * data) to ensure that hangup wakes us.
1231 */
1232 ret = lttng_poll_add(&events, ust_cmd.sock, LPOLLIN);
1233 if (ret < 0) {
1234 goto error;
1235 }
1236
1237 DBG("Apps with sock %d added to poll set",
1238 ust_cmd.sock);
1239 }
1240
1241 break;
1242 }
1243 } else {
1244 /*
1245 * At this point, we know that a registered application made
1246 * the event at poll_wait.
1247 */
1248 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1249 /* Removing from the poll set */
1250 ret = lttng_poll_del(&events, pollfd);
1251 if (ret < 0) {
1252 goto error;
1253 }
1254
1255 /* Socket closed on remote end. */
1256 ust_app_unregister(pollfd);
1257 break;
1258 }
1259 }
1260 }
1261 }
1262
1263 error:
1264 lttng_poll_clean(&events);
1265 error_poll_create:
1266 DBG("Application communication apps thread cleanup complete");
1267 rcu_thread_offline();
1268 rcu_unregister_thread();
1269 return NULL;
1270 }
1271
1272 /*
1273 * Dispatch request from the registration threads to the application
1274 * communication thread.
1275 */
1276 static void *thread_dispatch_ust_registration(void *data)
1277 {
1278 int ret;
1279 struct cds_wfq_node *node;
1280 struct ust_command *ust_cmd = NULL;
1281
1282 DBG("[thread] Dispatch UST command started");
1283
1284 while (!dispatch_thread_exit) {
1285 /* Atomically prepare the queue futex */
1286 futex_nto1_prepare(&ust_cmd_queue.futex);
1287
1288 do {
1289 /* Dequeue command for registration */
1290 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1291 if (node == NULL) {
1292 DBG("Woken up but nothing in the UST command queue");
1293 /* Continue thread execution */
1294 break;
1295 }
1296
1297 ust_cmd = caa_container_of(node, struct ust_command, node);
1298
1299 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1300 " gid:%d sock:%d name:%s (version %d.%d)",
1301 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1302 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1303 ust_cmd->sock, ust_cmd->reg_msg.name,
1304 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1305 /*
1306 * Inform apps thread of the new application registration. This
1307 * call is blocking so we can be assured that the data will be read
1308 * at some point in time or wait to the end of the world :)
1309 */
1310 ret = write(apps_cmd_pipe[1], ust_cmd,
1311 sizeof(struct ust_command));
1312 if (ret < 0) {
1313 PERROR("write apps cmd pipe");
1314 if (errno == EBADF) {
1315 /*
1316 * We can't inform the application thread to process
1317 * registration. We will exit or else application
1318 * registration will not occur and tracing will never
1319 * start.
1320 */
1321 goto error;
1322 }
1323 }
1324 free(ust_cmd);
1325 } while (node != NULL);
1326
1327 /* Futex wait on queue. Blocking call on futex() */
1328 futex_nto1_wait(&ust_cmd_queue.futex);
1329 }
1330
1331 error:
1332 DBG("Dispatch thread dying");
1333 return NULL;
1334 }
1335
1336 /*
1337 * This thread manage application registration.
1338 */
1339 static void *thread_registration_apps(void *data)
1340 {
1341 int sock = -1, i, ret, pollfd;
1342 uint32_t revents, nb_fd;
1343 struct lttng_poll_event events;
1344 /*
1345 * Get allocated in this thread, enqueued to a global queue, dequeued and
1346 * freed in the manage apps thread.
1347 */
1348 struct ust_command *ust_cmd = NULL;
1349
1350 DBG("[thread] Manage application registration started");
1351
1352 ret = lttcomm_listen_unix_sock(apps_sock);
1353 if (ret < 0) {
1354 goto error_listen;
1355 }
1356
1357 /*
1358 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1359 * more will be added to this poll set.
1360 */
1361 ret = create_thread_poll_set(&events, 2);
1362 if (ret < 0) {
1363 goto error_create_poll;
1364 }
1365
1366 /* Add the application registration socket */
1367 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1368 if (ret < 0) {
1369 goto error_poll_add;
1370 }
1371
1372 /* Notify all applications to register */
1373 ret = notify_ust_apps(1);
1374 if (ret < 0) {
1375 ERR("Failed to notify applications or create the wait shared memory.\n"
1376 "Execution continues but there might be problem for already\n"
1377 "running applications that wishes to register.");
1378 }
1379
1380 while (1) {
1381 DBG("Accepting application registration");
1382
1383 nb_fd = LTTNG_POLL_GETNB(&events);
1384
1385 /* Inifinite blocking call, waiting for transmission */
1386 restart:
1387 ret = lttng_poll_wait(&events, -1);
1388 if (ret < 0) {
1389 /*
1390 * Restart interrupted system call.
1391 */
1392 if (errno == EINTR) {
1393 goto restart;
1394 }
1395 goto error;
1396 }
1397
1398 for (i = 0; i < nb_fd; i++) {
1399 /* Fetch once the poll data */
1400 revents = LTTNG_POLL_GETEV(&events, i);
1401 pollfd = LTTNG_POLL_GETFD(&events, i);
1402
1403 /* Thread quit pipe has been closed. Killing thread. */
1404 ret = check_thread_quit_pipe(pollfd, revents);
1405 if (ret) {
1406 goto error;
1407 }
1408
1409 /* Event on the registration socket */
1410 if (pollfd == apps_sock) {
1411 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1412 ERR("Register apps socket poll error");
1413 goto error;
1414 } else if (revents & LPOLLIN) {
1415 sock = lttcomm_accept_unix_sock(apps_sock);
1416 if (sock < 0) {
1417 goto error;
1418 }
1419
1420 /* Create UST registration command for enqueuing */
1421 ust_cmd = zmalloc(sizeof(struct ust_command));
1422 if (ust_cmd == NULL) {
1423 PERROR("ust command zmalloc");
1424 goto error;
1425 }
1426
1427 /*
1428 * Using message-based transmissions to ensure we don't
1429 * have to deal with partially received messages.
1430 */
1431 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1432 sizeof(struct ust_register_msg));
1433 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1434 if (ret < 0) {
1435 PERROR("lttcomm_recv_unix_sock register apps");
1436 } else {
1437 ERR("Wrong size received on apps register");
1438 }
1439 free(ust_cmd);
1440 ret = close(sock);
1441 if (ret) {
1442 PERROR("close");
1443 }
1444 sock = -1;
1445 continue;
1446 }
1447
1448 ust_cmd->sock = sock;
1449 sock = -1;
1450
1451 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1452 " gid:%d sock:%d name:%s (version %d.%d)",
1453 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1454 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1455 ust_cmd->sock, ust_cmd->reg_msg.name,
1456 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1457
1458 /*
1459 * Lock free enqueue the registration request. The red pill
1460 * has been taken! This apps will be part of the *system*.
1461 */
1462 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1463
1464 /*
1465 * Wake the registration queue futex. Implicit memory
1466 * barrier with the exchange in cds_wfq_enqueue.
1467 */
1468 futex_nto1_wake(&ust_cmd_queue.futex);
1469 }
1470 }
1471 }
1472 }
1473
1474 error:
1475 /* Notify that the registration thread is gone */
1476 notify_ust_apps(0);
1477
1478 if (apps_sock >= 0) {
1479 ret = close(apps_sock);
1480 if (ret) {
1481 PERROR("close");
1482 }
1483 }
1484 if (sock >= 0) {
1485 ret = close(sock);
1486 if (ret) {
1487 PERROR("close");
1488 }
1489 }
1490 unlink(apps_unix_sock_path);
1491
1492 error_poll_add:
1493 lttng_poll_clean(&events);
1494 error_listen:
1495 error_create_poll:
1496 DBG("UST Registration thread cleanup complete");
1497
1498 return NULL;
1499 }
1500
1501 /*
1502 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1503 * exec or it will fails.
1504 */
1505 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1506 {
1507 int ret;
1508 struct timespec timeout;
1509
1510 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1511 timeout.tv_nsec = 0;
1512
1513 /* Setup semaphore */
1514 ret = sem_init(&consumer_data->sem, 0, 0);
1515 if (ret < 0) {
1516 PERROR("sem_init consumer semaphore");
1517 goto error;
1518 }
1519
1520 ret = pthread_create(&consumer_data->thread, NULL,
1521 thread_manage_consumer, consumer_data);
1522 if (ret != 0) {
1523 PERROR("pthread_create consumer");
1524 ret = -1;
1525 goto error;
1526 }
1527
1528 /* Get time for sem_timedwait absolute timeout */
1529 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1530 if (ret < 0) {
1531 PERROR("clock_gettime spawn consumer");
1532 /* Infinite wait for the kconsumerd thread to be ready */
1533 ret = sem_wait(&consumer_data->sem);
1534 } else {
1535 /* Normal timeout if the gettime was successful */
1536 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1537 ret = sem_timedwait(&consumer_data->sem, &timeout);
1538 }
1539
1540 if (ret < 0) {
1541 if (errno == ETIMEDOUT) {
1542 /*
1543 * Call has timed out so we kill the kconsumerd_thread and return
1544 * an error.
1545 */
1546 ERR("The consumer thread was never ready. Killing it");
1547 ret = pthread_cancel(consumer_data->thread);
1548 if (ret < 0) {
1549 PERROR("pthread_cancel consumer thread");
1550 }
1551 } else {
1552 PERROR("semaphore wait failed consumer thread");
1553 }
1554 goto error;
1555 }
1556
1557 pthread_mutex_lock(&consumer_data->pid_mutex);
1558 if (consumer_data->pid == 0) {
1559 ERR("Kconsumerd did not start");
1560 pthread_mutex_unlock(&consumer_data->pid_mutex);
1561 goto error;
1562 }
1563 pthread_mutex_unlock(&consumer_data->pid_mutex);
1564
1565 return 0;
1566
1567 error:
1568 return ret;
1569 }
1570
1571 /*
1572 * Join consumer thread
1573 */
1574 static int join_consumer_thread(struct consumer_data *consumer_data)
1575 {
1576 void *status;
1577 int ret;
1578
1579 if (consumer_data->pid != 0) {
1580 ret = kill(consumer_data->pid, SIGTERM);
1581 if (ret) {
1582 ERR("Error killing consumer daemon");
1583 return ret;
1584 }
1585 return pthread_join(consumer_data->thread, &status);
1586 } else {
1587 return 0;
1588 }
1589 }
1590
1591 /*
1592 * Fork and exec a consumer daemon (consumerd).
1593 *
1594 * Return pid if successful else -1.
1595 */
1596 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1597 {
1598 int ret;
1599 pid_t pid;
1600 const char *consumer_to_use;
1601 const char *verbosity;
1602 struct stat st;
1603
1604 DBG("Spawning consumerd");
1605
1606 pid = fork();
1607 if (pid == 0) {
1608 /*
1609 * Exec consumerd.
1610 */
1611 if (opt_verbose_consumer) {
1612 verbosity = "--verbose";
1613 } else {
1614 verbosity = "--quiet";
1615 }
1616 switch (consumer_data->type) {
1617 case LTTNG_CONSUMER_KERNEL:
1618 /*
1619 * Find out which consumerd to execute. We will first try the
1620 * 64-bit path, then the sessiond's installation directory, and
1621 * fallback on the 32-bit one,
1622 */
1623 DBG3("Looking for a kernel consumer at these locations:");
1624 DBG3(" 1) %s", consumerd64_bin);
1625 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1626 DBG3(" 3) %s", consumerd32_bin);
1627 if (stat(consumerd64_bin, &st) == 0) {
1628 DBG3("Found location #1");
1629 consumer_to_use = consumerd64_bin;
1630 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1631 DBG3("Found location #2");
1632 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1633 } else if (stat(consumerd32_bin, &st) == 0) {
1634 DBG3("Found location #3");
1635 consumer_to_use = consumerd32_bin;
1636 } else {
1637 DBG("Could not find any valid consumerd executable");
1638 break;
1639 }
1640 DBG("Using kernel consumer at: %s", consumer_to_use);
1641 execl(consumer_to_use,
1642 "lttng-consumerd", verbosity, "-k",
1643 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1644 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1645 NULL);
1646 break;
1647 case LTTNG_CONSUMER64_UST:
1648 {
1649 char *tmpnew = NULL;
1650
1651 if (consumerd64_libdir[0] != '\0') {
1652 char *tmp;
1653 size_t tmplen;
1654
1655 tmp = getenv("LD_LIBRARY_PATH");
1656 if (!tmp) {
1657 tmp = "";
1658 }
1659 tmplen = strlen("LD_LIBRARY_PATH=")
1660 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1661 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1662 if (!tmpnew) {
1663 ret = -ENOMEM;
1664 goto error;
1665 }
1666 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1667 strcat(tmpnew, consumerd64_libdir);
1668 if (tmp[0] != '\0') {
1669 strcat(tmpnew, ":");
1670 strcat(tmpnew, tmp);
1671 }
1672 ret = putenv(tmpnew);
1673 if (ret) {
1674 ret = -errno;
1675 goto error;
1676 }
1677 }
1678 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1679 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1680 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1681 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1682 NULL);
1683 if (consumerd64_libdir[0] != '\0') {
1684 free(tmpnew);
1685 }
1686 if (ret) {
1687 goto error;
1688 }
1689 break;
1690 }
1691 case LTTNG_CONSUMER32_UST:
1692 {
1693 char *tmpnew = NULL;
1694
1695 if (consumerd32_libdir[0] != '\0') {
1696 char *tmp;
1697 size_t tmplen;
1698
1699 tmp = getenv("LD_LIBRARY_PATH");
1700 if (!tmp) {
1701 tmp = "";
1702 }
1703 tmplen = strlen("LD_LIBRARY_PATH=")
1704 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1705 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1706 if (!tmpnew) {
1707 ret = -ENOMEM;
1708 goto error;
1709 }
1710 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1711 strcat(tmpnew, consumerd32_libdir);
1712 if (tmp[0] != '\0') {
1713 strcat(tmpnew, ":");
1714 strcat(tmpnew, tmp);
1715 }
1716 ret = putenv(tmpnew);
1717 if (ret) {
1718 ret = -errno;
1719 goto error;
1720 }
1721 }
1722 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1723 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1724 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1725 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1726 NULL);
1727 if (consumerd32_libdir[0] != '\0') {
1728 free(tmpnew);
1729 }
1730 if (ret) {
1731 goto error;
1732 }
1733 break;
1734 }
1735 default:
1736 PERROR("unknown consumer type");
1737 exit(EXIT_FAILURE);
1738 }
1739 if (errno != 0) {
1740 PERROR("kernel start consumer exec");
1741 }
1742 exit(EXIT_FAILURE);
1743 } else if (pid > 0) {
1744 ret = pid;
1745 } else {
1746 PERROR("start consumer fork");
1747 ret = -errno;
1748 }
1749 error:
1750 return ret;
1751 }
1752
1753 /*
1754 * Spawn the consumerd daemon and session daemon thread.
1755 */
1756 static int start_consumerd(struct consumer_data *consumer_data)
1757 {
1758 int ret;
1759
1760 pthread_mutex_lock(&consumer_data->pid_mutex);
1761 if (consumer_data->pid != 0) {
1762 pthread_mutex_unlock(&consumer_data->pid_mutex);
1763 goto end;
1764 }
1765
1766 ret = spawn_consumerd(consumer_data);
1767 if (ret < 0) {
1768 ERR("Spawning consumerd failed");
1769 pthread_mutex_unlock(&consumer_data->pid_mutex);
1770 goto error;
1771 }
1772
1773 /* Setting up the consumer_data pid */
1774 consumer_data->pid = ret;
1775 DBG2("Consumer pid %d", consumer_data->pid);
1776 pthread_mutex_unlock(&consumer_data->pid_mutex);
1777
1778 DBG2("Spawning consumer control thread");
1779 ret = spawn_consumer_thread(consumer_data);
1780 if (ret < 0) {
1781 ERR("Fatal error spawning consumer control thread");
1782 goto error;
1783 }
1784
1785 end:
1786 return 0;
1787
1788 error:
1789 return ret;
1790 }
1791
1792 /*
1793 * Check version of the lttng-modules.
1794 */
1795 static int validate_lttng_modules_version(void)
1796 {
1797 return kernel_validate_version(kernel_tracer_fd);
1798 }
1799
1800 /*
1801 * Setup necessary data for kernel tracer action.
1802 */
1803 static int init_kernel_tracer(void)
1804 {
1805 int ret;
1806
1807 /* Modprobe lttng kernel modules */
1808 ret = modprobe_lttng_control();
1809 if (ret < 0) {
1810 goto error;
1811 }
1812
1813 /* Open debugfs lttng */
1814 kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
1815 if (kernel_tracer_fd < 0) {
1816 DBG("Failed to open %s", module_proc_lttng);
1817 ret = -1;
1818 goto error_open;
1819 }
1820
1821 /* Validate kernel version */
1822 ret = validate_lttng_modules_version();
1823 if (ret < 0) {
1824 goto error_version;
1825 }
1826
1827 ret = modprobe_lttng_data();
1828 if (ret < 0) {
1829 goto error_modules;
1830 }
1831
1832 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1833 return 0;
1834
1835 error_version:
1836 modprobe_remove_lttng_control();
1837 ret = close(kernel_tracer_fd);
1838 if (ret) {
1839 PERROR("close");
1840 }
1841 kernel_tracer_fd = -1;
1842 return LTTCOMM_KERN_VERSION;
1843
1844 error_modules:
1845 ret = close(kernel_tracer_fd);
1846 if (ret) {
1847 PERROR("close");
1848 }
1849
1850 error_open:
1851 modprobe_remove_lttng_control();
1852
1853 error:
1854 WARN("No kernel tracer available");
1855 kernel_tracer_fd = -1;
1856 if (!is_root) {
1857 return LTTCOMM_NEED_ROOT_SESSIOND;
1858 } else {
1859 return LTTCOMM_KERN_NA;
1860 }
1861 }
1862
1863 /*
1864 * Init tracing by creating trace directory and sending fds kernel consumer.
1865 */
1866 static int init_kernel_tracing(struct ltt_kernel_session *session)
1867 {
1868 int ret = 0;
1869
1870 if (session->consumer_fds_sent == 0) {
1871 /*
1872 * Assign default kernel consumer socket if no consumer assigned to the
1873 * kernel session. At this point, it's NOT supposed to be -1 but this is
1874 * an extra security check.
1875 */
1876 if (session->consumer_fd < 0) {
1877 session->consumer_fd = kconsumer_data.cmd_sock;
1878 }
1879
1880 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1881 if (ret < 0) {
1882 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1883 goto error;
1884 }
1885
1886 session->consumer_fds_sent = 1;
1887 }
1888
1889 error:
1890 return ret;
1891 }
1892
1893 /*
1894 * Create an UST session and add it to the session ust list.
1895 */
1896 static int create_ust_session(struct ltt_session *session,
1897 struct lttng_domain *domain)
1898 {
1899 struct ltt_ust_session *lus = NULL;
1900 int ret;
1901
1902 switch (domain->type) {
1903 case LTTNG_DOMAIN_UST:
1904 break;
1905 default:
1906 ret = LTTCOMM_UNKNOWN_DOMAIN;
1907 goto error;
1908 }
1909
1910 DBG("Creating UST session");
1911
1912 lus = trace_ust_create_session(session->path, session->id, domain);
1913 if (lus == NULL) {
1914 ret = LTTCOMM_UST_SESS_FAIL;
1915 goto error;
1916 }
1917
1918 ret = run_as_mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1919 session->uid, session->gid);
1920 if (ret < 0) {
1921 if (ret != -EEXIST) {
1922 ERR("Trace directory creation error");
1923 ret = LTTCOMM_UST_SESS_FAIL;
1924 goto error;
1925 }
1926 }
1927
1928 /* The domain type dictate different actions on session creation */
1929 switch (domain->type) {
1930 case LTTNG_DOMAIN_UST:
1931 /* No ustctl for the global UST domain */
1932 break;
1933 default:
1934 ERR("Unknown UST domain on create session %d", domain->type);
1935 goto error;
1936 }
1937 lus->uid = session->uid;
1938 lus->gid = session->gid;
1939 session->ust_session = lus;
1940
1941 return LTTCOMM_OK;
1942
1943 error:
1944 free(lus);
1945 return ret;
1946 }
1947
1948 /*
1949 * Create a kernel tracer session then create the default channel.
1950 */
1951 static int create_kernel_session(struct ltt_session *session)
1952 {
1953 int ret;
1954
1955 DBG("Creating kernel session");
1956
1957 ret = kernel_create_session(session, kernel_tracer_fd);
1958 if (ret < 0) {
1959 ret = LTTCOMM_KERN_SESS_FAIL;
1960 goto error;
1961 }
1962
1963 /* Set kernel consumer socket fd */
1964 if (kconsumer_data.cmd_sock >= 0) {
1965 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1966 }
1967
1968 ret = run_as_mkdir_recursive(session->kernel_session->trace_path,
1969 S_IRWXU | S_IRWXG, session->uid, session->gid);
1970 if (ret < 0) {
1971 if (ret != -EEXIST) {
1972 ERR("Trace directory creation error");
1973 goto error;
1974 }
1975 }
1976 session->kernel_session->uid = session->uid;
1977 session->kernel_session->gid = session->gid;
1978
1979 error:
1980 return ret;
1981 }
1982
1983 /*
1984 * Check if the UID or GID match the session. Root user has access to all
1985 * sessions.
1986 */
1987 static int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid)
1988 {
1989 if (uid != session->uid && gid != session->gid && uid != 0) {
1990 return 0;
1991 } else {
1992 return 1;
1993 }
1994 }
1995
1996 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
1997 {
1998 unsigned int i = 0;
1999 struct ltt_session *session;
2000
2001 DBG("Counting number of available session for UID %d GID %d",
2002 uid, gid);
2003 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2004 /*
2005 * Only list the sessions the user can control.
2006 */
2007 if (!session_access_ok(session, uid, gid)) {
2008 continue;
2009 }
2010 i++;
2011 }
2012 return i;
2013 }
2014
2015 /*
2016 * Using the session list, filled a lttng_session array to send back to the
2017 * client for session listing.
2018 *
2019 * The session list lock MUST be acquired before calling this function. Use
2020 * session_lock_list() and session_unlock_list().
2021 */
2022 static void list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2023 gid_t gid)
2024 {
2025 unsigned int i = 0;
2026 struct ltt_session *session;
2027
2028 DBG("Getting all available session for UID %d GID %d",
2029 uid, gid);
2030 /*
2031 * Iterate over session list and append data after the control struct in
2032 * the buffer.
2033 */
2034 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2035 /*
2036 * Only list the sessions the user can control.
2037 */
2038 if (!session_access_ok(session, uid, gid)) {
2039 continue;
2040 }
2041 strncpy(sessions[i].path, session->path, PATH_MAX);
2042 sessions[i].path[PATH_MAX - 1] = '\0';
2043 strncpy(sessions[i].name, session->name, NAME_MAX);
2044 sessions[i].name[NAME_MAX - 1] = '\0';
2045 sessions[i].enabled = session->enabled;
2046 i++;
2047 }
2048 }
2049
2050 /*
2051 * Fill lttng_channel array of all channels.
2052 */
2053 static void list_lttng_channels(int domain, struct ltt_session *session,
2054 struct lttng_channel *channels)
2055 {
2056 int i = 0;
2057 struct ltt_kernel_channel *kchan;
2058
2059 DBG("Listing channels for session %s", session->name);
2060
2061 switch (domain) {
2062 case LTTNG_DOMAIN_KERNEL:
2063 /* Kernel channels */
2064 if (session->kernel_session != NULL) {
2065 cds_list_for_each_entry(kchan,
2066 &session->kernel_session->channel_list.head, list) {
2067 /* Copy lttng_channel struct to array */
2068 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2069 channels[i].enabled = kchan->enabled;
2070 i++;
2071 }
2072 }
2073 break;
2074 case LTTNG_DOMAIN_UST:
2075 {
2076 struct lttng_ht_iter iter;
2077 struct ltt_ust_channel *uchan;
2078
2079 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
2080 &iter.iter, uchan, node.node) {
2081 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2082 channels[i].attr.overwrite = uchan->attr.overwrite;
2083 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2084 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2085 channels[i].attr.switch_timer_interval =
2086 uchan->attr.switch_timer_interval;
2087 channels[i].attr.read_timer_interval =
2088 uchan->attr.read_timer_interval;
2089 channels[i].enabled = uchan->enabled;
2090 switch (uchan->attr.output) {
2091 case LTTNG_UST_MMAP:
2092 default:
2093 channels[i].attr.output = LTTNG_EVENT_MMAP;
2094 break;
2095 }
2096 i++;
2097 }
2098 break;
2099 }
2100 default:
2101 break;
2102 }
2103 }
2104
2105 /*
2106 * Create a list of ust global domain events.
2107 */
2108 static int list_lttng_ust_global_events(char *channel_name,
2109 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2110 {
2111 int i = 0, ret = 0;
2112 unsigned int nb_event = 0;
2113 struct lttng_ht_iter iter;
2114 struct lttng_ht_node_str *node;
2115 struct ltt_ust_channel *uchan;
2116 struct ltt_ust_event *uevent;
2117 struct lttng_event *tmp;
2118
2119 DBG("Listing UST global events for channel %s", channel_name);
2120
2121 rcu_read_lock();
2122
2123 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2124 node = lttng_ht_iter_get_node_str(&iter);
2125 if (node == NULL) {
2126 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2127 goto error;
2128 }
2129
2130 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2131
2132 nb_event += lttng_ht_get_count(uchan->events);
2133
2134 if (nb_event == 0) {
2135 ret = nb_event;
2136 goto error;
2137 }
2138
2139 DBG3("Listing UST global %d events", nb_event);
2140
2141 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2142 if (tmp == NULL) {
2143 ret = -LTTCOMM_FATAL;
2144 goto error;
2145 }
2146
2147 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2148 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2149 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2150 tmp[i].enabled = uevent->enabled;
2151 switch (uevent->attr.instrumentation) {
2152 case LTTNG_UST_TRACEPOINT:
2153 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2154 break;
2155 case LTTNG_UST_PROBE:
2156 tmp[i].type = LTTNG_EVENT_PROBE;
2157 break;
2158 case LTTNG_UST_FUNCTION:
2159 tmp[i].type = LTTNG_EVENT_FUNCTION;
2160 break;
2161 }
2162 tmp[i].loglevel = uevent->attr.loglevel;
2163 switch (uevent->attr.loglevel_type) {
2164 case LTTNG_UST_LOGLEVEL_ALL:
2165 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2166 break;
2167 case LTTNG_UST_LOGLEVEL_RANGE:
2168 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
2169 break;
2170 case LTTNG_UST_LOGLEVEL_SINGLE:
2171 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
2172 break;
2173 }
2174 i++;
2175 }
2176
2177 ret = nb_event;
2178 *events = tmp;
2179
2180 error:
2181 rcu_read_unlock();
2182 return ret;
2183 }
2184
2185 /*
2186 * Fill lttng_event array of all kernel events in the channel.
2187 */
2188 static int list_lttng_kernel_events(char *channel_name,
2189 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2190 {
2191 int i = 0, ret;
2192 unsigned int nb_event;
2193 struct ltt_kernel_event *event;
2194 struct ltt_kernel_channel *kchan;
2195
2196 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2197 if (kchan == NULL) {
2198 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2199 goto error;
2200 }
2201
2202 nb_event = kchan->event_count;
2203
2204 DBG("Listing events for channel %s", kchan->channel->name);
2205
2206 if (nb_event == 0) {
2207 ret = nb_event;
2208 goto error;
2209 }
2210
2211 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2212 if (*events == NULL) {
2213 ret = LTTCOMM_FATAL;
2214 goto error;
2215 }
2216
2217 /* Kernel channels */
2218 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2219 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2220 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2221 (*events)[i].enabled = event->enabled;
2222 switch (event->event->instrumentation) {
2223 case LTTNG_KERNEL_TRACEPOINT:
2224 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2225 break;
2226 case LTTNG_KERNEL_KPROBE:
2227 case LTTNG_KERNEL_KRETPROBE:
2228 (*events)[i].type = LTTNG_EVENT_PROBE;
2229 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2230 sizeof(struct lttng_kernel_kprobe));
2231 break;
2232 case LTTNG_KERNEL_FUNCTION:
2233 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2234 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2235 sizeof(struct lttng_kernel_function));
2236 break;
2237 case LTTNG_KERNEL_NOOP:
2238 (*events)[i].type = LTTNG_EVENT_NOOP;
2239 break;
2240 case LTTNG_KERNEL_SYSCALL:
2241 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2242 break;
2243 case LTTNG_KERNEL_ALL:
2244 assert(0);
2245 break;
2246 }
2247 i++;
2248 }
2249
2250 return nb_event;
2251
2252 error:
2253 return ret;
2254 }
2255
2256 /*
2257 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2258 */
2259 static int cmd_disable_channel(struct ltt_session *session,
2260 int domain, char *channel_name)
2261 {
2262 int ret;
2263 struct ltt_ust_session *usess;
2264
2265 usess = session->ust_session;
2266
2267 switch (domain) {
2268 case LTTNG_DOMAIN_KERNEL:
2269 {
2270 ret = channel_kernel_disable(session->kernel_session,
2271 channel_name);
2272 if (ret != LTTCOMM_OK) {
2273 goto error;
2274 }
2275
2276 kernel_wait_quiescent(kernel_tracer_fd);
2277 break;
2278 }
2279 case LTTNG_DOMAIN_UST:
2280 {
2281 struct ltt_ust_channel *uchan;
2282 struct lttng_ht *chan_ht;
2283
2284 chan_ht = usess->domain_global.channels;
2285
2286 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2287 if (uchan == NULL) {
2288 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2289 goto error;
2290 }
2291
2292 ret = channel_ust_disable(usess, domain, uchan);
2293 if (ret != LTTCOMM_OK) {
2294 goto error;
2295 }
2296 break;
2297 }
2298 #if 0
2299 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2300 case LTTNG_DOMAIN_UST_EXEC_NAME:
2301 case LTTNG_DOMAIN_UST_PID:
2302 #endif
2303 default:
2304 ret = LTTCOMM_UNKNOWN_DOMAIN;
2305 goto error;
2306 }
2307
2308 ret = LTTCOMM_OK;
2309
2310 error:
2311 return ret;
2312 }
2313
2314 /*
2315 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2316 */
2317 static int cmd_enable_channel(struct ltt_session *session,
2318 int domain, struct lttng_channel *attr)
2319 {
2320 int ret;
2321 struct ltt_ust_session *usess = session->ust_session;
2322 struct lttng_ht *chan_ht;
2323
2324 DBG("Enabling channel %s for session %s", attr->name, session->name);
2325
2326 switch (domain) {
2327 case LTTNG_DOMAIN_KERNEL:
2328 {
2329 struct ltt_kernel_channel *kchan;
2330
2331 kchan = trace_kernel_get_channel_by_name(attr->name,
2332 session->kernel_session);
2333 if (kchan == NULL) {
2334 ret = channel_kernel_create(session->kernel_session,
2335 attr, kernel_poll_pipe[1]);
2336 } else {
2337 ret = channel_kernel_enable(session->kernel_session, kchan);
2338 }
2339
2340 if (ret != LTTCOMM_OK) {
2341 goto error;
2342 }
2343
2344 kernel_wait_quiescent(kernel_tracer_fd);
2345 break;
2346 }
2347 case LTTNG_DOMAIN_UST:
2348 {
2349 struct ltt_ust_channel *uchan;
2350
2351 chan_ht = usess->domain_global.channels;
2352
2353 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2354 if (uchan == NULL) {
2355 ret = channel_ust_create(usess, domain, attr);
2356 } else {
2357 ret = channel_ust_enable(usess, domain, uchan);
2358 }
2359 break;
2360 }
2361 #if 0
2362 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2363 case LTTNG_DOMAIN_UST_EXEC_NAME:
2364 case LTTNG_DOMAIN_UST_PID:
2365 #endif
2366 default:
2367 ret = LTTCOMM_UNKNOWN_DOMAIN;
2368 goto error;
2369 }
2370
2371 error:
2372 return ret;
2373 }
2374
2375 /*
2376 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2377 */
2378 static int cmd_disable_event(struct ltt_session *session, int domain,
2379 char *channel_name, char *event_name)
2380 {
2381 int ret;
2382
2383 switch (domain) {
2384 case LTTNG_DOMAIN_KERNEL:
2385 {
2386 struct ltt_kernel_channel *kchan;
2387 struct ltt_kernel_session *ksess;
2388
2389 ksess = session->kernel_session;
2390
2391 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2392 if (kchan == NULL) {
2393 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2394 goto error;
2395 }
2396
2397 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2398 if (ret != LTTCOMM_OK) {
2399 goto error;
2400 }
2401
2402 kernel_wait_quiescent(kernel_tracer_fd);
2403 break;
2404 }
2405 case LTTNG_DOMAIN_UST:
2406 {
2407 struct ltt_ust_channel *uchan;
2408 struct ltt_ust_session *usess;
2409
2410 usess = session->ust_session;
2411
2412 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2413 channel_name);
2414 if (uchan == NULL) {
2415 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2416 goto error;
2417 }
2418
2419 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2420 if (ret != LTTCOMM_OK) {
2421 goto error;
2422 }
2423
2424 DBG3("Disable UST event %s in channel %s completed", event_name,
2425 channel_name);
2426 break;
2427 }
2428 #if 0
2429 case LTTNG_DOMAIN_UST_EXEC_NAME:
2430 case LTTNG_DOMAIN_UST_PID:
2431 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2432 #endif
2433 default:
2434 ret = LTTCOMM_UND;
2435 goto error;
2436 }
2437
2438 ret = LTTCOMM_OK;
2439
2440 error:
2441 return ret;
2442 }
2443
2444 /*
2445 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2446 */
2447 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2448 char *channel_name)
2449 {
2450 int ret;
2451
2452 switch (domain) {
2453 case LTTNG_DOMAIN_KERNEL:
2454 {
2455 struct ltt_kernel_session *ksess;
2456 struct ltt_kernel_channel *kchan;
2457
2458 ksess = session->kernel_session;
2459
2460 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2461 if (kchan == NULL) {
2462 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2463 goto error;
2464 }
2465
2466 ret = event_kernel_disable_all(ksess, kchan);
2467 if (ret != LTTCOMM_OK) {
2468 goto error;
2469 }
2470
2471 kernel_wait_quiescent(kernel_tracer_fd);
2472 break;
2473 }
2474 case LTTNG_DOMAIN_UST:
2475 {
2476 struct ltt_ust_session *usess;
2477 struct ltt_ust_channel *uchan;
2478
2479 usess = session->ust_session;
2480
2481 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2482 channel_name);
2483 if (uchan == NULL) {
2484 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2485 goto error;
2486 }
2487
2488 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2489 if (ret != 0) {
2490 goto error;
2491 }
2492
2493 DBG3("Disable all UST events in channel %s completed", channel_name);
2494
2495 break;
2496 }
2497 #if 0
2498 case LTTNG_DOMAIN_UST_EXEC_NAME:
2499 case LTTNG_DOMAIN_UST_PID:
2500 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2501 #endif
2502 default:
2503 ret = LTTCOMM_UND;
2504 goto error;
2505 }
2506
2507 ret = LTTCOMM_OK;
2508
2509 error:
2510 return ret;
2511 }
2512
2513 /*
2514 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2515 */
2516 static int cmd_add_context(struct ltt_session *session, int domain,
2517 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2518 {
2519 int ret;
2520
2521 switch (domain) {
2522 case LTTNG_DOMAIN_KERNEL:
2523 /* Add kernel context to kernel tracer */
2524 ret = context_kernel_add(session->kernel_session, ctx,
2525 event_name, channel_name);
2526 if (ret != LTTCOMM_OK) {
2527 goto error;
2528 }
2529 break;
2530 case LTTNG_DOMAIN_UST:
2531 {
2532 struct ltt_ust_session *usess = session->ust_session;
2533
2534 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2535 if (ret != LTTCOMM_OK) {
2536 goto error;
2537 }
2538 break;
2539 }
2540 #if 0
2541 case LTTNG_DOMAIN_UST_EXEC_NAME:
2542 case LTTNG_DOMAIN_UST_PID:
2543 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2544 #endif
2545 default:
2546 ret = LTTCOMM_UND;
2547 goto error;
2548 }
2549
2550 ret = LTTCOMM_OK;
2551
2552 error:
2553 return ret;
2554 }
2555
2556 /*
2557 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2558 */
2559 static int cmd_enable_event(struct ltt_session *session, int domain,
2560 char *channel_name, struct lttng_event *event)
2561 {
2562 int ret;
2563 struct lttng_channel *attr;
2564 struct ltt_ust_session *usess = session->ust_session;
2565
2566 switch (domain) {
2567 case LTTNG_DOMAIN_KERNEL:
2568 {
2569 struct ltt_kernel_channel *kchan;
2570
2571 kchan = trace_kernel_get_channel_by_name(channel_name,
2572 session->kernel_session);
2573 if (kchan == NULL) {
2574 attr = channel_new_default_attr(domain);
2575 if (attr == NULL) {
2576 ret = LTTCOMM_FATAL;
2577 goto error;
2578 }
2579 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2580
2581 /* This call will notify the kernel thread */
2582 ret = channel_kernel_create(session->kernel_session,
2583 attr, kernel_poll_pipe[1]);
2584 if (ret != LTTCOMM_OK) {
2585 free(attr);
2586 goto error;
2587 }
2588 free(attr);
2589 }
2590
2591 /* Get the newly created kernel channel pointer */
2592 kchan = trace_kernel_get_channel_by_name(channel_name,
2593 session->kernel_session);
2594 if (kchan == NULL) {
2595 /* This sould not happen... */
2596 ret = LTTCOMM_FATAL;
2597 goto error;
2598 }
2599
2600 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2601 event);
2602 if (ret != LTTCOMM_OK) {
2603 goto error;
2604 }
2605
2606 kernel_wait_quiescent(kernel_tracer_fd);
2607 break;
2608 }
2609 case LTTNG_DOMAIN_UST:
2610 {
2611 struct lttng_channel *attr;
2612 struct ltt_ust_channel *uchan;
2613
2614 /* Get channel from global UST domain */
2615 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2616 channel_name);
2617 if (uchan == NULL) {
2618 /* Create default channel */
2619 attr = channel_new_default_attr(domain);
2620 if (attr == NULL) {
2621 ret = LTTCOMM_FATAL;
2622 goto error;
2623 }
2624 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2625 attr->name[NAME_MAX - 1] = '\0';
2626
2627 ret = channel_ust_create(usess, domain, attr);
2628 if (ret != LTTCOMM_OK) {
2629 free(attr);
2630 goto error;
2631 }
2632 free(attr);
2633
2634 /* Get the newly created channel reference back */
2635 uchan = trace_ust_find_channel_by_name(
2636 usess->domain_global.channels, channel_name);
2637 if (uchan == NULL) {
2638 /* Something is really wrong */
2639 ret = LTTCOMM_FATAL;
2640 goto error;
2641 }
2642 }
2643
2644 /* At this point, the session and channel exist on the tracer */
2645 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2646 if (ret != LTTCOMM_OK) {
2647 goto error;
2648 }
2649 break;
2650 }
2651 #if 0
2652 case LTTNG_DOMAIN_UST_EXEC_NAME:
2653 case LTTNG_DOMAIN_UST_PID:
2654 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2655 #endif
2656 default:
2657 ret = LTTCOMM_UND;
2658 goto error;
2659 }
2660
2661 ret = LTTCOMM_OK;
2662
2663 error:
2664 return ret;
2665 }
2666
2667 /*
2668 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2669 */
2670 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2671 char *channel_name, int event_type)
2672 {
2673 int ret;
2674 struct ltt_kernel_channel *kchan;
2675
2676 switch (domain) {
2677 case LTTNG_DOMAIN_KERNEL:
2678 kchan = trace_kernel_get_channel_by_name(channel_name,
2679 session->kernel_session);
2680 if (kchan == NULL) {
2681 /* This call will notify the kernel thread */
2682 ret = channel_kernel_create(session->kernel_session, NULL,
2683 kernel_poll_pipe[1]);
2684 if (ret != LTTCOMM_OK) {
2685 goto error;
2686 }
2687
2688 /* Get the newly created kernel channel pointer */
2689 kchan = trace_kernel_get_channel_by_name(channel_name,
2690 session->kernel_session);
2691 if (kchan == NULL) {
2692 /* This sould not happen... */
2693 ret = LTTCOMM_FATAL;
2694 goto error;
2695 }
2696
2697 }
2698
2699 switch (event_type) {
2700 case LTTNG_EVENT_SYSCALL:
2701 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2702 kchan, kernel_tracer_fd);
2703 break;
2704 case LTTNG_EVENT_TRACEPOINT:
2705 /*
2706 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2707 * events already registered to the channel.
2708 */
2709 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2710 kchan, kernel_tracer_fd);
2711 break;
2712 case LTTNG_EVENT_ALL:
2713 /* Enable syscalls and tracepoints */
2714 ret = event_kernel_enable_all(session->kernel_session,
2715 kchan, kernel_tracer_fd);
2716 break;
2717 default:
2718 ret = LTTCOMM_KERN_ENABLE_FAIL;
2719 goto error;
2720 }
2721
2722 /* Manage return value */
2723 if (ret != LTTCOMM_OK) {
2724 goto error;
2725 }
2726
2727 kernel_wait_quiescent(kernel_tracer_fd);
2728 break;
2729 case LTTNG_DOMAIN_UST:
2730 {
2731 struct lttng_channel *attr;
2732 struct ltt_ust_channel *uchan;
2733 struct ltt_ust_session *usess = session->ust_session;
2734
2735 /* Get channel from global UST domain */
2736 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2737 channel_name);
2738 if (uchan == NULL) {
2739 /* Create default channel */
2740 attr = channel_new_default_attr(domain);
2741 if (attr == NULL) {
2742 ret = LTTCOMM_FATAL;
2743 goto error;
2744 }
2745 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2746 attr->name[NAME_MAX - 1] = '\0';
2747
2748 /* Use the internal command enable channel */
2749 ret = channel_ust_create(usess, domain, attr);
2750 if (ret != LTTCOMM_OK) {
2751 free(attr);
2752 goto error;
2753 }
2754 free(attr);
2755
2756 /* Get the newly created channel reference back */
2757 uchan = trace_ust_find_channel_by_name(
2758 usess->domain_global.channels, channel_name);
2759 if (uchan == NULL) {
2760 /* Something is really wrong */
2761 ret = LTTCOMM_FATAL;
2762 goto error;
2763 }
2764 }
2765
2766 /* At this point, the session and channel exist on the tracer */
2767
2768 switch (event_type) {
2769 case LTTNG_EVENT_ALL:
2770 case LTTNG_EVENT_TRACEPOINT:
2771 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2772 if (ret != LTTCOMM_OK) {
2773 goto error;
2774 }
2775 break;
2776 default:
2777 ret = LTTCOMM_UST_ENABLE_FAIL;
2778 goto error;
2779 }
2780
2781 /* Manage return value */
2782 if (ret != LTTCOMM_OK) {
2783 goto error;
2784 }
2785
2786 break;
2787 }
2788 #if 0
2789 case LTTNG_DOMAIN_UST_EXEC_NAME:
2790 case LTTNG_DOMAIN_UST_PID:
2791 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2792 #endif
2793 default:
2794 ret = LTTCOMM_UND;
2795 goto error;
2796 }
2797
2798 ret = LTTCOMM_OK;
2799
2800 error:
2801 return ret;
2802 }
2803
2804 /*
2805 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2806 */
2807 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2808 {
2809 int ret;
2810 ssize_t nb_events = 0;
2811
2812 switch (domain) {
2813 case LTTNG_DOMAIN_KERNEL:
2814 nb_events = kernel_list_events(kernel_tracer_fd, events);
2815 if (nb_events < 0) {
2816 ret = LTTCOMM_KERN_LIST_FAIL;
2817 goto error;
2818 }
2819 break;
2820 case LTTNG_DOMAIN_UST:
2821 nb_events = ust_app_list_events(events);
2822 if (nb_events < 0) {
2823 ret = LTTCOMM_UST_LIST_FAIL;
2824 goto error;
2825 }
2826 break;
2827 default:
2828 ret = LTTCOMM_UND;
2829 goto error;
2830 }
2831
2832 return nb_events;
2833
2834 error:
2835 /* Return negative value to differentiate return code */
2836 return -ret;
2837 }
2838
2839 /*
2840 * Command LTTNG_START_TRACE processed by the client thread.
2841 */
2842 static int cmd_start_trace(struct ltt_session *session)
2843 {
2844 int ret;
2845 struct ltt_kernel_session *ksession;
2846 struct ltt_ust_session *usess;
2847
2848 /* Short cut */
2849 ksession = session->kernel_session;
2850 usess = session->ust_session;
2851
2852 if (session->enabled) {
2853 ret = LTTCOMM_UST_START_FAIL;
2854 goto error;
2855 }
2856
2857 session->enabled = 1;
2858
2859 /* Kernel tracing */
2860 if (ksession != NULL) {
2861 struct ltt_kernel_channel *kchan;
2862
2863 /* Open kernel metadata */
2864 if (ksession->metadata == NULL) {
2865 ret = kernel_open_metadata(ksession, ksession->trace_path);
2866 if (ret < 0) {
2867 ret = LTTCOMM_KERN_META_FAIL;
2868 goto error;
2869 }
2870 }
2871
2872 /* Open kernel metadata stream */
2873 if (ksession->metadata_stream_fd < 0) {
2874 ret = kernel_open_metadata_stream(ksession);
2875 if (ret < 0) {
2876 ERR("Kernel create metadata stream failed");
2877 ret = LTTCOMM_KERN_STREAM_FAIL;
2878 goto error;
2879 }
2880 }
2881
2882 /* For each channel */
2883 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2884 if (kchan->stream_count == 0) {
2885 ret = kernel_open_channel_stream(kchan);
2886 if (ret < 0) {
2887 ret = LTTCOMM_KERN_STREAM_FAIL;
2888 goto error;
2889 }
2890 /* Update the stream global counter */
2891 ksession->stream_count_global += ret;
2892 }
2893 }
2894
2895 /* Setup kernel consumer socket and send fds to it */
2896 ret = init_kernel_tracing(ksession);
2897 if (ret < 0) {
2898 ret = LTTCOMM_KERN_START_FAIL;
2899 goto error;
2900 }
2901
2902 /* This start the kernel tracing */
2903 ret = kernel_start_session(ksession);
2904 if (ret < 0) {
2905 ret = LTTCOMM_KERN_START_FAIL;
2906 goto error;
2907 }
2908
2909 /* Quiescent wait after starting trace */
2910 kernel_wait_quiescent(kernel_tracer_fd);
2911 }
2912
2913 /* Flag session that trace should start automatically */
2914 if (usess) {
2915 usess->start_trace = 1;
2916
2917 ret = ust_app_start_trace_all(usess);
2918 if (ret < 0) {
2919 ret = LTTCOMM_UST_START_FAIL;
2920 goto error;
2921 }
2922 }
2923
2924 ret = LTTCOMM_OK;
2925
2926 error:
2927 return ret;
2928 }
2929
2930 /*
2931 * Command LTTNG_STOP_TRACE processed by the client thread.
2932 */
2933 static int cmd_stop_trace(struct ltt_session *session)
2934 {
2935 int ret;
2936 struct ltt_kernel_channel *kchan;
2937 struct ltt_kernel_session *ksession;
2938 struct ltt_ust_session *usess;
2939
2940 /* Short cut */
2941 ksession = session->kernel_session;
2942 usess = session->ust_session;
2943
2944 if (!session->enabled) {
2945 ret = LTTCOMM_UST_STOP_FAIL;
2946 goto error;
2947 }
2948
2949 session->enabled = 0;
2950
2951 /* Kernel tracer */
2952 if (ksession != NULL) {
2953 DBG("Stop kernel tracing");
2954
2955 /* Flush all buffers before stopping */
2956 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2957 if (ret < 0) {
2958 ERR("Kernel metadata flush failed");
2959 }
2960
2961 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2962 ret = kernel_flush_buffer(kchan);
2963 if (ret < 0) {
2964 ERR("Kernel flush buffer error");
2965 }
2966 }
2967
2968 ret = kernel_stop_session(ksession);
2969 if (ret < 0) {
2970 ret = LTTCOMM_KERN_STOP_FAIL;
2971 goto error;
2972 }
2973
2974 kernel_wait_quiescent(kernel_tracer_fd);
2975 }
2976
2977 if (usess) {
2978 usess->start_trace = 0;
2979
2980 ret = ust_app_stop_trace_all(usess);
2981 if (ret < 0) {
2982 ret = LTTCOMM_UST_STOP_FAIL;
2983 goto error;
2984 }
2985 }
2986
2987 ret = LTTCOMM_OK;
2988
2989 error:
2990 return ret;
2991 }
2992
2993 /*
2994 * Command LTTNG_CREATE_SESSION processed by the client thread.
2995 */
2996 static int cmd_create_session(char *name, char *path, lttng_sock_cred *creds)
2997 {
2998 int ret;
2999
3000 ret = session_create(name, path, LTTNG_SOCK_GET_UID_CRED(creds),
3001 LTTNG_SOCK_GET_GID_CRED(creds));
3002 if (ret != LTTCOMM_OK) {
3003 goto error;
3004 }
3005
3006 ret = LTTCOMM_OK;
3007
3008 error:
3009 return ret;
3010 }
3011
3012 /*
3013 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3014 */
3015 static int cmd_destroy_session(struct ltt_session *session, char *name)
3016 {
3017 int ret;
3018
3019 /* Clean kernel session teardown */
3020 teardown_kernel_session(session);
3021 /* UST session teardown */
3022 teardown_ust_session(session);
3023
3024 /*
3025 * Must notify the kernel thread here to update it's poll setin order
3026 * to remove the channel(s)' fd just destroyed.
3027 */
3028 ret = notify_thread_pipe(kernel_poll_pipe[1]);
3029 if (ret < 0) {
3030 PERROR("write kernel poll pipe");
3031 }
3032
3033 ret = session_destroy(session);
3034
3035 return ret;
3036 }
3037
3038 /*
3039 * Command LTTNG_CALIBRATE processed by the client thread.
3040 */
3041 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3042 {
3043 int ret;
3044
3045 switch (domain) {
3046 case LTTNG_DOMAIN_KERNEL:
3047 {
3048 struct lttng_kernel_calibrate kcalibrate;
3049
3050 kcalibrate.type = calibrate->type;
3051 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3052 if (ret < 0) {
3053 ret = LTTCOMM_KERN_ENABLE_FAIL;
3054 goto error;
3055 }
3056 break;
3057 }
3058 case LTTNG_DOMAIN_UST:
3059 {
3060 struct lttng_ust_calibrate ucalibrate;
3061
3062 ucalibrate.type = calibrate->type;
3063 ret = ust_app_calibrate_glb(&ucalibrate);
3064 if (ret < 0) {
3065 ret = LTTCOMM_UST_CALIBRATE_FAIL;
3066 goto error;
3067 }
3068 break;
3069 }
3070 default:
3071 ret = LTTCOMM_UND;
3072 goto error;
3073 }
3074
3075 ret = LTTCOMM_OK;
3076
3077 error:
3078 return ret;
3079 }
3080
3081 /*
3082 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3083 */
3084 static int cmd_register_consumer(struct ltt_session *session, int domain,
3085 char *sock_path)
3086 {
3087 int ret, sock;
3088
3089 switch (domain) {
3090 case LTTNG_DOMAIN_KERNEL:
3091 /* Can't register a consumer if there is already one */
3092 if (session->kernel_session->consumer_fds_sent != 0) {
3093 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3094 goto error;
3095 }
3096
3097 sock = lttcomm_connect_unix_sock(sock_path);
3098 if (sock < 0) {
3099 ret = LTTCOMM_CONNECT_FAIL;
3100 goto error;
3101 }
3102
3103 session->kernel_session->consumer_fd = sock;
3104 break;
3105 default:
3106 /* TODO: Userspace tracing */
3107 ret = LTTCOMM_UND;
3108 goto error;
3109 }
3110
3111 ret = LTTCOMM_OK;
3112
3113 error:
3114 return ret;
3115 }
3116
3117 /*
3118 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3119 */
3120 static ssize_t cmd_list_domains(struct ltt_session *session,
3121 struct lttng_domain **domains)
3122 {
3123 int ret, index = 0;
3124 ssize_t nb_dom = 0;
3125
3126 if (session->kernel_session != NULL) {
3127 DBG3("Listing domains found kernel domain");
3128 nb_dom++;
3129 }
3130
3131 if (session->ust_session != NULL) {
3132 DBG3("Listing domains found UST global domain");
3133 nb_dom++;
3134 }
3135
3136 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3137 if (*domains == NULL) {
3138 ret = -LTTCOMM_FATAL;
3139 goto error;
3140 }
3141
3142 if (session->kernel_session != NULL) {
3143 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3144 index++;
3145 }
3146
3147 if (session->ust_session != NULL) {
3148 (*domains)[index].type = LTTNG_DOMAIN_UST;
3149 index++;
3150 }
3151
3152 return nb_dom;
3153
3154 error:
3155 return ret;
3156 }
3157
3158 /*
3159 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3160 */
3161 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3162 struct lttng_channel **channels)
3163 {
3164 int ret;
3165 ssize_t nb_chan = 0;
3166
3167 switch (domain) {
3168 case LTTNG_DOMAIN_KERNEL:
3169 if (session->kernel_session != NULL) {
3170 nb_chan = session->kernel_session->channel_count;
3171 }
3172 DBG3("Number of kernel channels %zd", nb_chan);
3173 break;
3174 case LTTNG_DOMAIN_UST:
3175 if (session->ust_session != NULL) {
3176 nb_chan = lttng_ht_get_count(
3177 session->ust_session->domain_global.channels);
3178 }
3179 DBG3("Number of UST global channels %zd", nb_chan);
3180 break;
3181 default:
3182 *channels = NULL;
3183 ret = -LTTCOMM_UND;
3184 goto error;
3185 }
3186
3187 if (nb_chan > 0) {
3188 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3189 if (*channels == NULL) {
3190 ret = -LTTCOMM_FATAL;
3191 goto error;
3192 }
3193
3194 list_lttng_channels(domain, session, *channels);
3195 } else {
3196 *channels = NULL;
3197 }
3198
3199 return nb_chan;
3200
3201 error:
3202 return ret;
3203 }
3204
3205 /*
3206 * Command LTTNG_LIST_EVENTS processed by the client thread.
3207 */
3208 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3209 char *channel_name, struct lttng_event **events)
3210 {
3211 int ret = 0;
3212 ssize_t nb_event = 0;
3213
3214 switch (domain) {
3215 case LTTNG_DOMAIN_KERNEL:
3216 if (session->kernel_session != NULL) {
3217 nb_event = list_lttng_kernel_events(channel_name,
3218 session->kernel_session, events);
3219 }
3220 break;
3221 case LTTNG_DOMAIN_UST:
3222 {
3223 if (session->ust_session != NULL) {
3224 nb_event = list_lttng_ust_global_events(channel_name,
3225 &session->ust_session->domain_global, events);
3226 }
3227 break;
3228 }
3229 default:
3230 ret = -LTTCOMM_UND;
3231 goto error;
3232 }
3233
3234 ret = nb_event;
3235
3236 error:
3237 return ret;
3238 }
3239
3240 /*
3241 * Process the command requested by the lttng client within the command
3242 * context structure. This function make sure that the return structure (llm)
3243 * is set and ready for transmission before returning.
3244 *
3245 * Return any error encountered or 0 for success.
3246 */
3247 static int process_client_msg(struct command_ctx *cmd_ctx)
3248 {
3249 int ret = LTTCOMM_OK;
3250 int need_tracing_session = 1;
3251 int need_domain;
3252
3253 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3254
3255 switch (cmd_ctx->lsm->cmd_type) {
3256 case LTTNG_CREATE_SESSION:
3257 case LTTNG_DESTROY_SESSION:
3258 case LTTNG_LIST_SESSIONS:
3259 case LTTNG_LIST_DOMAINS:
3260 case LTTNG_START_TRACE:
3261 case LTTNG_STOP_TRACE:
3262 need_domain = 0;
3263 break;
3264 default:
3265 need_domain = 1;
3266 }
3267</