Fix: replace 'modprobe -l' by lsmod in kernel test
[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
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 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 #include "fd-limit.h"
58
59 #define CONSUMERD_FILE "lttng-consumerd"
60
61 struct consumer_data {
62 enum lttng_consumer_type type;
63
64 pthread_t thread; /* Worker thread interacting with the consumer */
65 sem_t sem;
66
67 /* Mutex to control consumerd pid assignation */
68 pthread_mutex_t pid_mutex;
69 pid_t pid;
70
71 int err_sock;
72 int cmd_sock;
73
74 /* consumer error and command Unix socket path */
75 char err_unix_sock_path[PATH_MAX];
76 char cmd_unix_sock_path[PATH_MAX];
77 };
78
79 /* Const values */
80 const char default_home_dir[] = DEFAULT_HOME_DIR;
81 const char default_tracing_group[] = DEFAULT_TRACING_GROUP;
82 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
83 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
84
85 const char *progname;
86 const char *opt_tracing_group;
87 static int opt_sig_parent;
88 static int opt_verbose_consumer;
89 static int opt_daemon;
90 static int opt_no_kernel;
91 static int is_root; /* Set to 1 if the daemon is running as root */
92 static pid_t ppid; /* Parent PID for --sig-parent option */
93 static char *rundir;
94
95 /* Consumer daemon specific control data */
96 static struct consumer_data kconsumer_data = {
97 .type = LTTNG_CONSUMER_KERNEL,
98 .err_unix_sock_path = DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
99 .cmd_unix_sock_path = DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
100 .err_sock = -1,
101 .cmd_sock = -1,
102 };
103 static struct consumer_data ustconsumer64_data = {
104 .type = LTTNG_CONSUMER64_UST,
105 .err_unix_sock_path = DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
106 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
107 .err_sock = -1,
108 .cmd_sock = -1,
109 };
110 static struct consumer_data ustconsumer32_data = {
111 .type = LTTNG_CONSUMER32_UST,
112 .err_unix_sock_path = DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
113 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
114 .err_sock = -1,
115 .cmd_sock = -1,
116 };
117
118 static int dispatch_thread_exit;
119
120 /* Global application Unix socket path */
121 static char apps_unix_sock_path[PATH_MAX];
122 /* Global client Unix socket path */
123 static char client_unix_sock_path[PATH_MAX];
124 /* global wait shm path for UST */
125 static char wait_shm_path[PATH_MAX];
126
127 /* Sockets and FDs */
128 static int client_sock = -1;
129 static int apps_sock = -1;
130 static int kernel_tracer_fd = -1;
131 static int kernel_poll_pipe[2] = { -1, -1 };
132
133 /*
134 * Quit pipe for all threads. This permits a single cancellation point
135 * for all threads when receiving an event on the pipe.
136 */
137 static int thread_quit_pipe[2] = { -1, -1 };
138
139 /*
140 * This pipe is used to inform the thread managing application communication
141 * that a command is queued and ready to be processed.
142 */
143 static int apps_cmd_pipe[2] = { -1, -1 };
144
145 /* Pthread, Mutexes and Semaphores */
146 static pthread_t apps_thread;
147 static pthread_t reg_apps_thread;
148 static pthread_t client_thread;
149 static pthread_t kernel_thread;
150 static pthread_t dispatch_thread;
151
152
153 /*
154 * UST registration command queue. This queue is tied with a futex and uses a N
155 * wakers / 1 waiter implemented and detailed in futex.c/.h
156 *
157 * The thread_manage_apps and thread_dispatch_ust_registration interact with
158 * this queue and the wait/wake scheme.
159 */
160 static struct ust_cmd_queue ust_cmd_queue;
161
162 /*
163 * Pointer initialized before thread creation.
164 *
165 * This points to the tracing session list containing the session count and a
166 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
167 * MUST NOT be taken if you call a public function in session.c.
168 *
169 * The lock is nested inside the structure: session_list_ptr->lock. Please use
170 * session_lock_list and session_unlock_list for lock acquisition.
171 */
172 static struct ltt_session_list *session_list_ptr;
173
174 int ust_consumerd64_fd = -1;
175 int ust_consumerd32_fd = -1;
176
177 static const char *consumerd32_bin = CONFIG_CONSUMERD32_BIN;
178 static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
179 static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
180 static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
181
182 static
183 void setup_consumerd_path(void)
184 {
185 const char *bin, *libdir;
186
187 /*
188 * Allow INSTALL_BIN_PATH to be used as a target path for the
189 * native architecture size consumer if CONFIG_CONSUMER*_PATH
190 * has not been defined.
191 */
192 #if (CAA_BITS_PER_LONG == 32)
193 if (!consumerd32_bin[0]) {
194 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
195 }
196 if (!consumerd32_libdir[0]) {
197 consumerd32_libdir = INSTALL_LIB_PATH;
198 }
199 #elif (CAA_BITS_PER_LONG == 64)
200 if (!consumerd64_bin[0]) {
201 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
202 }
203 if (!consumerd64_libdir[0]) {
204 consumerd64_libdir = INSTALL_LIB_PATH;
205 }
206 #else
207 #error "Unknown bitness"
208 #endif
209
210 /*
211 * runtime env. var. overrides the build default.
212 */
213 bin = getenv("LTTNG_CONSUMERD32_BIN");
214 if (bin) {
215 consumerd32_bin = bin;
216 }
217 bin = getenv("LTTNG_CONSUMERD64_BIN");
218 if (bin) {
219 consumerd64_bin = bin;
220 }
221 libdir = getenv("LTTNG_CONSUMERD32_LIBDIR");
222 if (libdir) {
223 consumerd32_libdir = libdir;
224 }
225 libdir = getenv("LTTNG_CONSUMERD64_LIBDIR");
226 if (libdir) {
227 consumerd64_libdir = libdir;
228 }
229 }
230
231 /*
232 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
233 */
234 static int create_thread_poll_set(struct lttng_poll_event *events,
235 unsigned int size)
236 {
237 int ret;
238
239 if (events == NULL || size == 0) {
240 ret = -1;
241 goto error;
242 }
243
244 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
245 if (ret < 0) {
246 goto error;
247 }
248
249 /* Add quit pipe */
250 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
251 if (ret < 0) {
252 goto error;
253 }
254
255 return 0;
256
257 error:
258 return ret;
259 }
260
261 /*
262 * Check if the thread quit pipe was triggered.
263 *
264 * Return 1 if it was triggered else 0;
265 */
266 static int check_thread_quit_pipe(int fd, uint32_t events)
267 {
268 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
269 return 1;
270 }
271
272 return 0;
273 }
274
275 /*
276 * Return group ID of the tracing group or -1 if not found.
277 */
278 static gid_t allowed_group(void)
279 {
280 struct group *grp;
281
282 if (opt_tracing_group) {
283 grp = getgrnam(opt_tracing_group);
284 } else {
285 grp = getgrnam(default_tracing_group);
286 }
287 if (!grp) {
288 return -1;
289 } else {
290 return grp->gr_gid;
291 }
292 }
293
294 /*
295 * Init thread quit pipe.
296 *
297 * Return -1 on error or 0 if all pipes are created.
298 */
299 static int init_thread_quit_pipe(void)
300 {
301 int ret, i;
302
303 ret = pipe(thread_quit_pipe);
304 if (ret < 0) {
305 PERROR("thread quit pipe");
306 goto error;
307 }
308
309 for (i = 0; i < 2; i++) {
310 ret = fcntl(thread_quit_pipe[i], F_SETFD, FD_CLOEXEC);
311 if (ret < 0) {
312 PERROR("fcntl");
313 goto error;
314 }
315 }
316
317 error:
318 return ret;
319 }
320
321 /*
322 * Complete teardown of a kernel session. This free all data structure related
323 * to a kernel session and update counter.
324 */
325 static void teardown_kernel_session(struct ltt_session *session)
326 {
327 if (!session->kernel_session) {
328 DBG3("No kernel session when tearing down session");
329 return;
330 }
331
332 DBG("Tearing down kernel session");
333
334 /*
335 * If a custom kernel consumer was registered, close the socket before
336 * tearing down the complete kernel session structure
337 */
338 if (kconsumer_data.cmd_sock >= 0 &&
339 session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
340 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
341 }
342
343 trace_kernel_destroy_session(session->kernel_session);
344 }
345
346 /*
347 * Complete teardown of all UST sessions. This will free everything on his path
348 * and destroy the core essence of all ust sessions :)
349 */
350 static void teardown_ust_session(struct ltt_session *session)
351 {
352 int ret;
353
354 if (!session->ust_session) {
355 DBG3("No UST session when tearing down session");
356 return;
357 }
358
359 DBG("Tearing down UST session(s)");
360
361 ret = ust_app_destroy_trace_all(session->ust_session);
362 if (ret) {
363 ERR("Error in ust_app_destroy_trace_all");
364 }
365
366 trace_ust_destroy_session(session->ust_session);
367 }
368
369 /*
370 * Stop all threads by closing the thread quit pipe.
371 */
372 static void stop_threads(void)
373 {
374 int ret;
375
376 /* Stopping all threads */
377 DBG("Terminating all threads");
378 ret = notify_thread_pipe(thread_quit_pipe[1]);
379 if (ret < 0) {
380 ERR("write error on thread quit pipe");
381 }
382
383 /* Dispatch thread */
384 dispatch_thread_exit = 1;
385 futex_nto1_wake(&ust_cmd_queue.futex);
386 }
387
388 /*
389 * Cleanup the daemon
390 */
391 static void cleanup(void)
392 {
393 int ret, i;
394 char *cmd;
395 struct ltt_session *sess, *stmp;
396
397 DBG("Cleaning up");
398
399 DBG("Removing %s directory", rundir);
400 ret = asprintf(&cmd, "rm -rf %s", rundir);
401 if (ret < 0) {
402 ERR("asprintf failed. Something is really wrong!");
403 }
404
405 /* Remove lttng run directory */
406 ret = system(cmd);
407 if (ret < 0) {
408 ERR("Unable to clean %s", rundir);
409 }
410 free(cmd);
411
412 DBG("Cleaning up all sessions");
413
414 /* Destroy session list mutex */
415 if (session_list_ptr != NULL) {
416 pthread_mutex_destroy(&session_list_ptr->lock);
417
418 /* Cleanup ALL session */
419 cds_list_for_each_entry_safe(sess, stmp,
420 &session_list_ptr->head, list) {
421 teardown_kernel_session(sess);
422 teardown_ust_session(sess);
423 free(sess);
424 }
425 }
426
427 DBG("Closing all UST sockets");
428 ust_app_clean_list();
429
430 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
431
432 if (is_root && !opt_no_kernel) {
433 DBG2("Closing kernel fd");
434 if (kernel_tracer_fd >= 0) {
435 ret = close(kernel_tracer_fd);
436 if (ret) {
437 PERROR("close");
438 }
439 }
440 DBG("Unloading kernel modules");
441 modprobe_remove_lttng_all();
442 }
443
444 /*
445 * Closing all pipes used for communication between threads.
446 */
447 for (i = 0; i < 2; i++) {
448 if (kernel_poll_pipe[i] >= 0) {
449 ret = close(kernel_poll_pipe[i]);
450 if (ret) {
451 PERROR("close");
452 }
453
454 }
455 }
456 for (i = 0; i < 2; i++) {
457 if (thread_quit_pipe[i] >= 0) {
458 ret = close(thread_quit_pipe[i]);
459 if (ret) {
460 PERROR("close");
461 }
462 }
463 }
464 for (i = 0; i < 2; i++) {
465 if (apps_cmd_pipe[i] >= 0) {
466 ret = close(apps_cmd_pipe[i]);
467 if (ret) {
468 PERROR("close");
469 }
470 }
471 }
472
473 /* <fun> */
474 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
475 "Matthew, BEET driven development works!%c[%dm",
476 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
477 /* </fun> */
478 }
479
480 /*
481 * Send data on a unix socket using the liblttsessiondcomm API.
482 *
483 * Return lttcomm error code.
484 */
485 static int send_unix_sock(int sock, void *buf, size_t len)
486 {
487 /* Check valid length */
488 if (len <= 0) {
489 return -1;
490 }
491
492 return lttcomm_send_unix_sock(sock, buf, len);
493 }
494
495 /*
496 * Free memory of a command context structure.
497 */
498 static void clean_command_ctx(struct command_ctx **cmd_ctx)
499 {
500 DBG("Clean command context structure");
501 if (*cmd_ctx) {
502 if ((*cmd_ctx)->llm) {
503 free((*cmd_ctx)->llm);
504 }
505 if ((*cmd_ctx)->lsm) {
506 free((*cmd_ctx)->lsm);
507 }
508 free(*cmd_ctx);
509 *cmd_ctx = NULL;
510 }
511 }
512
513 /*
514 * Send all stream fds of kernel channel to the consumer.
515 */
516 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
517 int sock, struct ltt_kernel_channel *channel,
518 uid_t uid, gid_t gid)
519 {
520 int ret;
521 struct ltt_kernel_stream *stream;
522 struct lttcomm_consumer_msg lkm;
523
524 DBG("Sending streams of channel %s to kernel consumer",
525 channel->channel->name);
526
527 /* Send channel */
528 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
529 lkm.u.channel.channel_key = channel->fd;
530 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
531 lkm.u.channel.mmap_len = 0; /* for kernel */
532 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
533 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
534 if (ret < 0) {
535 PERROR("send consumer channel");
536 goto error;
537 }
538
539 /* Send streams */
540 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
541 if (!stream->fd) {
542 continue;
543 }
544 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
545 lkm.u.stream.channel_key = channel->fd;
546 lkm.u.stream.stream_key = stream->fd;
547 lkm.u.stream.state = stream->state;
548 lkm.u.stream.output = channel->channel->attr.output;
549 lkm.u.stream.mmap_len = 0; /* for kernel */
550 lkm.u.stream.uid = uid;
551 lkm.u.stream.gid = gid;
552 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
553 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
554 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
555 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
556 if (ret < 0) {
557 PERROR("send consumer stream");
558 goto error;
559 }
560 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
561 if (ret < 0) {
562 PERROR("send consumer stream ancillary data");
563 goto error;
564 }
565 }
566
567 DBG("consumer channel streams sent");
568
569 return 0;
570
571 error:
572 return ret;
573 }
574
575 /*
576 * Send all stream fds of the kernel session to the consumer.
577 */
578 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
579 struct ltt_kernel_session *session)
580 {
581 int ret;
582 struct ltt_kernel_channel *chan;
583 struct lttcomm_consumer_msg lkm;
584 int sock = session->consumer_fd;
585
586 DBG("Sending metadata stream fd");
587
588 /* Extra protection. It's NOT supposed to be set to -1 at this point */
589 if (session->consumer_fd < 0) {
590 session->consumer_fd = consumer_data->cmd_sock;
591 }
592
593 if (session->metadata_stream_fd >= 0) {
594 /* Send metadata channel fd */
595 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
596 lkm.u.channel.channel_key = session->metadata->fd;
597 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
598 lkm.u.channel.mmap_len = 0; /* for kernel */
599 DBG("Sending metadata channel %d to consumer", lkm.u.channel.channel_key);
600 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
601 if (ret < 0) {
602 PERROR("send consumer channel");
603 goto error;
604 }
605
606 /* Send metadata stream fd */
607 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
608 lkm.u.stream.channel_key = session->metadata->fd;
609 lkm.u.stream.stream_key = session->metadata_stream_fd;
610 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
611 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
612 lkm.u.stream.mmap_len = 0; /* for kernel */
613 lkm.u.stream.uid = session->uid;
614 lkm.u.stream.gid = session->gid;
615 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
616 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
617 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
618 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
619 if (ret < 0) {
620 PERROR("send consumer stream");
621 goto error;
622 }
623 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
624 if (ret < 0) {
625 PERROR("send consumer stream");
626 goto error;
627 }
628 }
629
630 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
631 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
632 session->uid, session->gid);
633 if (ret < 0) {
634 goto error;
635 }
636 }
637
638 DBG("consumer fds (metadata and channel streams) sent");
639
640 return 0;
641
642 error:
643 return ret;
644 }
645
646 /*
647 * Notify UST applications using the shm mmap futex.
648 */
649 static int notify_ust_apps(int active)
650 {
651 char *wait_shm_mmap;
652
653 DBG("Notifying applications of session daemon state: %d", active);
654
655 /* See shm.c for this call implying mmap, shm and futex calls */
656 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
657 if (wait_shm_mmap == NULL) {
658 goto error;
659 }
660
661 /* Wake waiting process */
662 futex_wait_update((int32_t *) wait_shm_mmap, active);
663
664 /* Apps notified successfully */
665 return 0;
666
667 error:
668 return -1;
669 }
670
671 /*
672 * Setup the outgoing data buffer for the response (llm) by allocating the
673 * right amount of memory and copying the original information from the lsm
674 * structure.
675 *
676 * Return total size of the buffer pointed by buf.
677 */
678 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
679 {
680 int ret, buf_size;
681
682 buf_size = size;
683
684 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
685 if (cmd_ctx->llm == NULL) {
686 PERROR("zmalloc");
687 ret = -ENOMEM;
688 goto error;
689 }
690
691 /* Copy common data */
692 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
693 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
694
695 cmd_ctx->llm->data_size = size;
696 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
697
698 return buf_size;
699
700 error:
701 return ret;
702 }
703
704 /*
705 * Update the kernel poll set of all channel fd available over all tracing
706 * session. Add the wakeup pipe at the end of the set.
707 */
708 static int update_kernel_poll(struct lttng_poll_event *events)
709 {
710 int ret;
711 struct ltt_session *session;
712 struct ltt_kernel_channel *channel;
713
714 DBG("Updating kernel poll set");
715
716 session_lock_list();
717 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
718 session_lock(session);
719 if (session->kernel_session == NULL) {
720 session_unlock(session);
721 continue;
722 }
723
724 cds_list_for_each_entry(channel,
725 &session->kernel_session->channel_list.head, list) {
726 /* Add channel fd to the kernel poll set */
727 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
728 if (ret < 0) {
729 session_unlock(session);
730 goto error;
731 }
732 DBG("Channel fd %d added to kernel set", channel->fd);
733 }
734 session_unlock(session);
735 }
736 session_unlock_list();
737
738 return 0;
739
740 error:
741 session_unlock_list();
742 return -1;
743 }
744
745 /*
746 * Find the channel fd from 'fd' over all tracing session. When found, check
747 * for new channel stream and send those stream fds to the kernel consumer.
748 *
749 * Useful for CPU hotplug feature.
750 */
751 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
752 {
753 int ret = 0;
754 struct ltt_session *session;
755 struct ltt_kernel_channel *channel;
756
757 DBG("Updating kernel streams for channel fd %d", fd);
758
759 session_lock_list();
760 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
761 session_lock(session);
762 if (session->kernel_session == NULL) {
763 session_unlock(session);
764 continue;
765 }
766
767 /* This is not suppose to be -1 but this is an extra security check */
768 if (session->kernel_session->consumer_fd < 0) {
769 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
770 }
771
772 cds_list_for_each_entry(channel,
773 &session->kernel_session->channel_list.head, list) {
774 if (channel->fd == fd) {
775 DBG("Channel found, updating kernel streams");
776 ret = kernel_open_channel_stream(channel);
777 if (ret < 0) {
778 goto error;
779 }
780
781 /*
782 * Have we already sent fds to the consumer? If yes, it means
783 * that tracing is started so it is safe to send our updated
784 * stream fds.
785 */
786 if (session->kernel_session->consumer_fds_sent == 1) {
787 ret = send_kconsumer_channel_streams(consumer_data,
788 session->kernel_session->consumer_fd, channel,
789 session->uid, session->gid);
790 if (ret < 0) {
791 goto error;
792 }
793 }
794 goto error;
795 }
796 }
797 session_unlock(session);
798 }
799 session_unlock_list();
800 return ret;
801
802 error:
803 session_unlock(session);
804 session_unlock_list();
805 return ret;
806 }
807
808 /*
809 * For each tracing session, update newly registered apps.
810 */
811 static void update_ust_app(int app_sock)
812 {
813 struct ltt_session *sess, *stmp;
814
815 session_lock_list();
816
817 /* For all tracing session(s) */
818 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
819 session_lock(sess);
820 if (sess->ust_session) {
821 ust_app_global_update(sess->ust_session, app_sock);
822 }
823 session_unlock(sess);
824 }
825
826 session_unlock_list();
827 }
828
829 /*
830 * This thread manage event coming from the kernel.
831 *
832 * Features supported in this thread:
833 * -) CPU Hotplug
834 */
835 static void *thread_manage_kernel(void *data)
836 {
837 int ret, i, pollfd, update_poll_flag = 1;
838 uint32_t revents, nb_fd;
839 char tmp;
840 struct lttng_poll_event events;
841
842 DBG("Thread manage kernel started");
843
844 ret = create_thread_poll_set(&events, 2);
845 if (ret < 0) {
846 goto error_poll_create;
847 }
848
849 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
850 if (ret < 0) {
851 goto error;
852 }
853
854 while (1) {
855 if (update_poll_flag == 1) {
856 /*
857 * Reset number of fd in the poll set. Always 2 since there is the thread
858 * quit pipe and the kernel pipe.
859 */
860 events.nb_fd = 2;
861
862 ret = update_kernel_poll(&events);
863 if (ret < 0) {
864 goto error;
865 }
866 update_poll_flag = 0;
867 }
868
869 nb_fd = LTTNG_POLL_GETNB(&events);
870
871 DBG("Thread kernel polling on %d fds", nb_fd);
872
873 /* Zeroed the poll events */
874 lttng_poll_reset(&events);
875
876 /* Poll infinite value of time */
877 restart:
878 ret = lttng_poll_wait(&events, -1);
879 if (ret < 0) {
880 /*
881 * Restart interrupted system call.
882 */
883 if (errno == EINTR) {
884 goto restart;
885 }
886 goto error;
887 } else if (ret == 0) {
888 /* Should not happen since timeout is infinite */
889 ERR("Return value of poll is 0 with an infinite timeout.\n"
890 "This should not have happened! Continuing...");
891 continue;
892 }
893
894 for (i = 0; i < nb_fd; i++) {
895 /* Fetch once the poll data */
896 revents = LTTNG_POLL_GETEV(&events, i);
897 pollfd = LTTNG_POLL_GETFD(&events, i);
898
899 /* Thread quit pipe has been closed. Killing thread. */
900 ret = check_thread_quit_pipe(pollfd, revents);
901 if (ret) {
902 goto error;
903 }
904
905 /* Check for data on kernel pipe */
906 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
907 ret = read(kernel_poll_pipe[0], &tmp, 1);
908 update_poll_flag = 1;
909 continue;
910 } else {
911 /*
912 * New CPU detected by the kernel. Adding kernel stream to
913 * kernel session and updating the kernel consumer
914 */
915 if (revents & LPOLLIN) {
916 ret = update_kernel_stream(&kconsumer_data, pollfd);
917 if (ret < 0) {
918 continue;
919 }
920 break;
921 /*
922 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
923 * and unregister kernel stream at this point.
924 */
925 }
926 }
927 }
928 }
929
930 error:
931 lttng_poll_clean(&events);
932 error_poll_create:
933 DBG("Kernel thread dying");
934 return NULL;
935 }
936
937 /*
938 * This thread manage the consumer error sent back to the session daemon.
939 */
940 static void *thread_manage_consumer(void *data)
941 {
942 int sock = -1, i, ret, pollfd;
943 uint32_t revents, nb_fd;
944 enum lttcomm_return_code code;
945 struct lttng_poll_event events;
946 struct consumer_data *consumer_data = data;
947
948 DBG("[thread] Manage consumer started");
949
950 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
951 if (ret < 0) {
952 goto error_listen;
953 }
954
955 /*
956 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
957 * Nothing more will be added to this poll set.
958 */
959 ret = create_thread_poll_set(&events, 2);
960 if (ret < 0) {
961 goto error_poll;
962 }
963
964 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
965 if (ret < 0) {
966 goto error;
967 }
968
969 nb_fd = LTTNG_POLL_GETNB(&events);
970
971 /* Inifinite blocking call, waiting for transmission */
972 restart:
973 ret = lttng_poll_wait(&events, -1);
974 if (ret < 0) {
975 /*
976 * Restart interrupted system call.
977 */
978 if (errno == EINTR) {
979 goto restart;
980 }
981 goto error;
982 }
983
984 for (i = 0; i < nb_fd; i++) {
985 /* Fetch once the poll data */
986 revents = LTTNG_POLL_GETEV(&events, i);
987 pollfd = LTTNG_POLL_GETFD(&events, i);
988
989 /* Thread quit pipe has been closed. Killing thread. */
990 ret = check_thread_quit_pipe(pollfd, revents);
991 if (ret) {
992 goto error;
993 }
994
995 /* Event on the registration socket */
996 if (pollfd == consumer_data->err_sock) {
997 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
998 ERR("consumer err socket poll error");
999 goto error;
1000 }
1001 }
1002 }
1003
1004 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
1005 if (sock < 0) {
1006 goto error;
1007 }
1008
1009 DBG2("Receiving code from consumer err_sock");
1010
1011 /* Getting status code from kconsumerd */
1012 ret = lttcomm_recv_unix_sock(sock, &code,
1013 sizeof(enum lttcomm_return_code));
1014 if (ret <= 0) {
1015 goto error;
1016 }
1017
1018 if (code == CONSUMERD_COMMAND_SOCK_READY) {
1019 consumer_data->cmd_sock =
1020 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
1021 if (consumer_data->cmd_sock < 0) {
1022 sem_post(&consumer_data->sem);
1023 PERROR("consumer connect");
1024 goto error;
1025 }
1026 /* Signal condition to tell that the kconsumerd is ready */
1027 sem_post(&consumer_data->sem);
1028 DBG("consumer command socket ready");
1029 } else {
1030 ERR("consumer error when waiting for SOCK_READY : %s",
1031 lttcomm_get_readable_code(-code));
1032 goto error;
1033 }
1034
1035 /* Remove the kconsumerd error sock since we've established a connexion */
1036 ret = lttng_poll_del(&events, consumer_data->err_sock);
1037 if (ret < 0) {
1038 goto error;
1039 }
1040
1041 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1042 if (ret < 0) {
1043 goto error;
1044 }
1045
1046 /* Update number of fd */
1047 nb_fd = LTTNG_POLL_GETNB(&events);
1048
1049 /* Inifinite blocking call, waiting for transmission */
1050 restart_poll:
1051 ret = lttng_poll_wait(&events, -1);
1052 if (ret < 0) {
1053 /*
1054 * Restart interrupted system call.
1055 */
1056 if (errno == EINTR) {
1057 goto restart_poll;
1058 }
1059 goto error;
1060 }
1061
1062 for (i = 0; i < nb_fd; i++) {
1063 /* Fetch once the poll data */
1064 revents = LTTNG_POLL_GETEV(&events, i);
1065 pollfd = LTTNG_POLL_GETFD(&events, i);
1066
1067 /* Thread quit pipe has been closed. Killing thread. */
1068 ret = check_thread_quit_pipe(pollfd, revents);
1069 if (ret) {
1070 goto error;
1071 }
1072
1073 /* Event on the kconsumerd socket */
1074 if (pollfd == sock) {
1075 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1076 ERR("consumer err socket second poll error");
1077 goto error;
1078 }
1079 }
1080 }
1081
1082 /* Wait for any kconsumerd error */
1083 ret = lttcomm_recv_unix_sock(sock, &code,
1084 sizeof(enum lttcomm_return_code));
1085 if (ret <= 0) {
1086 ERR("consumer closed the command socket");
1087 goto error;
1088 }
1089
1090 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1091
1092 error:
1093 if (consumer_data->err_sock >= 0) {
1094 ret = close(consumer_data->err_sock);
1095 if (ret) {
1096 PERROR("close");
1097 }
1098 }
1099 if (consumer_data->cmd_sock >= 0) {
1100 ret = close(consumer_data->cmd_sock);
1101 if (ret) {
1102 PERROR("close");
1103 }
1104 }
1105 if (sock >= 0) {
1106 ret = close(sock);
1107 if (ret) {
1108 PERROR("close");
1109 }
1110 }
1111
1112 unlink(consumer_data->err_unix_sock_path);
1113 unlink(consumer_data->cmd_unix_sock_path);
1114 consumer_data->pid = 0;
1115
1116 lttng_poll_clean(&events);
1117 error_poll:
1118 error_listen:
1119 DBG("consumer thread cleanup completed");
1120
1121 return NULL;
1122 }
1123
1124 /*
1125 * This thread manage application communication.
1126 */
1127 static void *thread_manage_apps(void *data)
1128 {
1129 int i, ret, pollfd;
1130 uint32_t revents, nb_fd;
1131 struct ust_command ust_cmd;
1132 struct lttng_poll_event events;
1133
1134 DBG("[thread] Manage application started");
1135
1136 rcu_register_thread();
1137 rcu_thread_online();
1138
1139 ret = create_thread_poll_set(&events, 2);
1140 if (ret < 0) {
1141 goto error_poll_create;
1142 }
1143
1144 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1145 if (ret < 0) {
1146 goto error;
1147 }
1148
1149 while (1) {
1150 /* Zeroed the events structure */
1151 lttng_poll_reset(&events);
1152
1153 nb_fd = LTTNG_POLL_GETNB(&events);
1154
1155 DBG("Apps thread polling on %d fds", nb_fd);
1156
1157 /* Inifinite blocking call, waiting for transmission */
1158 restart:
1159 ret = lttng_poll_wait(&events, -1);
1160 if (ret < 0) {
1161 /*
1162 * Restart interrupted system call.
1163 */
1164 if (errno == EINTR) {
1165 goto restart;
1166 }
1167 goto error;
1168 }
1169
1170 for (i = 0; i < nb_fd; i++) {
1171 /* Fetch once the poll data */
1172 revents = LTTNG_POLL_GETEV(&events, i);
1173 pollfd = LTTNG_POLL_GETFD(&events, i);
1174
1175 /* Thread quit pipe has been closed. Killing thread. */
1176 ret = check_thread_quit_pipe(pollfd, revents);
1177 if (ret) {
1178 goto error;
1179 }
1180
1181 /* Inspect the apps cmd pipe */
1182 if (pollfd == apps_cmd_pipe[0]) {
1183 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1184 ERR("Apps command pipe error");
1185 goto error;
1186 } else if (revents & LPOLLIN) {
1187 /* Empty pipe */
1188 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1189 if (ret < 0 || ret < sizeof(ust_cmd)) {
1190 PERROR("read apps cmd pipe");
1191 goto error;
1192 }
1193
1194 /* Register applicaton to the session daemon */
1195 ret = ust_app_register(&ust_cmd.reg_msg,
1196 ust_cmd.sock);
1197 if (ret == -ENOMEM) {
1198 goto error;
1199 } else if (ret < 0) {
1200 break;
1201 }
1202
1203 /*
1204 * Validate UST version compatibility.
1205 */
1206 ret = ust_app_validate_version(ust_cmd.sock);
1207 if (ret >= 0) {
1208 /*
1209 * Add channel(s) and event(s) to newly registered apps
1210 * from lttng global UST domain.
1211 */
1212 update_ust_app(ust_cmd.sock);
1213 }
1214
1215 ret = ust_app_register_done(ust_cmd.sock);
1216 if (ret < 0) {
1217 /*
1218 * If the registration is not possible, we simply
1219 * unregister the apps and continue
1220 */
1221 ust_app_unregister(ust_cmd.sock);
1222 } else {
1223 /*
1224 * We just need here to monitor the close of the UST
1225 * socket and poll set monitor those by default.
1226 * Listen on POLLIN (even if we never expect any
1227 * data) to ensure that hangup wakes us.
1228 */
1229 ret = lttng_poll_add(&events, ust_cmd.sock, LPOLLIN);
1230 if (ret < 0) {
1231 goto error;
1232 }
1233
1234 DBG("Apps with sock %d added to poll set",
1235 ust_cmd.sock);
1236 }
1237
1238 break;
1239 }
1240 } else {
1241 /*
1242 * At this point, we know that a registered application made
1243 * the event at poll_wait.
1244 */
1245 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1246 /* Removing from the poll set */
1247 ret = lttng_poll_del(&events, pollfd);
1248 if (ret < 0) {
1249 goto error;
1250 }
1251
1252 /* Socket closed on remote end. */
1253 ust_app_unregister(pollfd);
1254 break;
1255 }
1256 }
1257 }
1258 }
1259
1260 error:
1261 lttng_poll_clean(&events);
1262 error_poll_create:
1263 DBG("Application communication apps thread cleanup complete");
1264 rcu_thread_offline();
1265 rcu_unregister_thread();
1266 return NULL;
1267 }
1268
1269 /*
1270 * Dispatch request from the registration threads to the application
1271 * communication thread.
1272 */
1273 static void *thread_dispatch_ust_registration(void *data)
1274 {
1275 int ret;
1276 struct cds_wfq_node *node;
1277 struct ust_command *ust_cmd = NULL;
1278
1279 DBG("[thread] Dispatch UST command started");
1280
1281 while (!dispatch_thread_exit) {
1282 /* Atomically prepare the queue futex */
1283 futex_nto1_prepare(&ust_cmd_queue.futex);
1284
1285 do {
1286 /* Dequeue command for registration */
1287 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1288 if (node == NULL) {
1289 DBG("Woken up but nothing in the UST command queue");
1290 /* Continue thread execution */
1291 break;
1292 }
1293
1294 ust_cmd = caa_container_of(node, struct ust_command, node);
1295
1296 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1297 " gid:%d sock:%d name:%s (version %d.%d)",
1298 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1299 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1300 ust_cmd->sock, ust_cmd->reg_msg.name,
1301 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1302 /*
1303 * Inform apps thread of the new application registration. This
1304 * call is blocking so we can be assured that the data will be read
1305 * at some point in time or wait to the end of the world :)
1306 */
1307 ret = write(apps_cmd_pipe[1], ust_cmd,
1308 sizeof(struct ust_command));
1309 if (ret < 0) {
1310 PERROR("write apps cmd pipe");
1311 if (errno == EBADF) {
1312 /*
1313 * We can't inform the application thread to process
1314 * registration. We will exit or else application
1315 * registration will not occur and tracing will never
1316 * start.
1317 */
1318 goto error;
1319 }
1320 }
1321 free(ust_cmd);
1322 } while (node != NULL);
1323
1324 /* Futex wait on queue. Blocking call on futex() */
1325 futex_nto1_wait(&ust_cmd_queue.futex);
1326 }
1327
1328 error:
1329 DBG("Dispatch thread dying");
1330 return NULL;
1331 }
1332
1333 /*
1334 * This thread manage application registration.
1335 */
1336 static void *thread_registration_apps(void *data)
1337 {
1338 int sock = -1, i, ret, pollfd;
1339 uint32_t revents, nb_fd;
1340 struct lttng_poll_event events;
1341 /*
1342 * Get allocated in this thread, enqueued to a global queue, dequeued and
1343 * freed in the manage apps thread.
1344 */
1345 struct ust_command *ust_cmd = NULL;
1346
1347 DBG("[thread] Manage application registration started");
1348
1349 ret = lttcomm_listen_unix_sock(apps_sock);
1350 if (ret < 0) {
1351 goto error_listen;
1352 }
1353
1354 /*
1355 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1356 * more will be added to this poll set.
1357 */
1358 ret = create_thread_poll_set(&events, 2);
1359 if (ret < 0) {
1360 goto error_create_poll;
1361 }
1362
1363 /* Add the application registration socket */
1364 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1365 if (ret < 0) {
1366 goto error_poll_add;
1367 }
1368
1369 /* Notify all applications to register */
1370 ret = notify_ust_apps(1);
1371 if (ret < 0) {
1372 ERR("Failed to notify applications or create the wait shared memory.\n"
1373 "Execution continues but there might be problem for already\n"
1374 "running applications that wishes to register.");
1375 }
1376
1377 while (1) {
1378 DBG("Accepting application registration");
1379
1380 nb_fd = LTTNG_POLL_GETNB(&events);
1381
1382 /* Inifinite blocking call, waiting for transmission */
1383 restart:
1384 ret = lttng_poll_wait(&events, -1);
1385 if (ret < 0) {
1386 /*
1387 * Restart interrupted system call.
1388 */
1389 if (errno == EINTR) {
1390 goto restart;
1391 }
1392 goto error;
1393 }
1394
1395 for (i = 0; i < nb_fd; i++) {
1396 /* Fetch once the poll data */
1397 revents = LTTNG_POLL_GETEV(&events, i);
1398 pollfd = LTTNG_POLL_GETFD(&events, i);
1399
1400 /* Thread quit pipe has been closed. Killing thread. */
1401 ret = check_thread_quit_pipe(pollfd, revents);
1402 if (ret) {
1403 goto error;
1404 }
1405
1406 /* Event on the registration socket */
1407 if (pollfd == apps_sock) {
1408 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1409 ERR("Register apps socket poll error");
1410 goto error;
1411 } else if (revents & LPOLLIN) {
1412 sock = lttcomm_accept_unix_sock(apps_sock);
1413 if (sock < 0) {
1414 goto error;
1415 }
1416
1417 /* Create UST registration command for enqueuing */
1418 ust_cmd = zmalloc(sizeof(struct ust_command));
1419 if (ust_cmd == NULL) {
1420 PERROR("ust command zmalloc");
1421 goto error;
1422 }
1423
1424 /*
1425 * Using message-based transmissions to ensure we don't
1426 * have to deal with partially received messages.
1427 */
1428 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
1429 if (ret < 0) {
1430 ERR("Exhausted file descriptors allowed for applications.");
1431 free(ust_cmd);
1432 ret = close(sock);
1433 if (ret) {
1434 PERROR("close");
1435 }
1436 sock = -1;
1437 continue;
1438 }
1439 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1440 sizeof(struct ust_register_msg));
1441 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1442 if (ret < 0) {
1443 PERROR("lttcomm_recv_unix_sock register apps");
1444 } else {
1445 ERR("Wrong size received on apps register");
1446 }
1447 free(ust_cmd);
1448 ret = close(sock);
1449 if (ret) {
1450 PERROR("close");
1451 }
1452 lttng_fd_put(LTTNG_FD_APPS, 1);
1453 sock = -1;
1454 continue;
1455 }
1456
1457 ust_cmd->sock = sock;
1458 sock = -1;
1459
1460 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1461 " gid:%d sock:%d name:%s (version %d.%d)",
1462 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1463 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1464 ust_cmd->sock, ust_cmd->reg_msg.name,
1465 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1466
1467 /*
1468 * Lock free enqueue the registration request. The red pill
1469 * has been taken! This apps will be part of the *system*.
1470 */
1471 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1472
1473 /*
1474 * Wake the registration queue futex. Implicit memory
1475 * barrier with the exchange in cds_wfq_enqueue.
1476 */
1477 futex_nto1_wake(&ust_cmd_queue.futex);
1478 }
1479 }
1480 }
1481 }
1482
1483 error:
1484 /* Notify that the registration thread is gone */
1485 notify_ust_apps(0);
1486
1487 if (apps_sock >= 0) {
1488 ret = close(apps_sock);
1489 if (ret) {
1490 PERROR("close");
1491 }
1492 }
1493 if (sock >= 0) {
1494 ret = close(sock);
1495 if (ret) {
1496 PERROR("close");
1497 }
1498 lttng_fd_put(LTTNG_FD_APPS, 1);
1499 }
1500 unlink(apps_unix_sock_path);
1501
1502 error_poll_add:
1503 lttng_poll_clean(&events);
1504 error_listen:
1505 error_create_poll:
1506 DBG("UST Registration thread cleanup complete");
1507
1508 return NULL;
1509 }
1510
1511 /*
1512 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1513 * exec or it will fails.
1514 */
1515 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1516 {
1517 int ret;
1518 struct timespec timeout;
1519
1520 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1521 timeout.tv_nsec = 0;
1522
1523 /* Setup semaphore */
1524 ret = sem_init(&consumer_data->sem, 0, 0);
1525 if (ret < 0) {
1526 PERROR("sem_init consumer semaphore");
1527 goto error;
1528 }
1529
1530 ret = pthread_create(&consumer_data->thread, NULL,
1531 thread_manage_consumer, consumer_data);
1532 if (ret != 0) {
1533 PERROR("pthread_create consumer");
1534 ret = -1;
1535 goto error;
1536 }
1537
1538 /* Get time for sem_timedwait absolute timeout */
1539 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1540 if (ret < 0) {
1541 PERROR("clock_gettime spawn consumer");
1542 /* Infinite wait for the kconsumerd thread to be ready */
1543 ret = sem_wait(&consumer_data->sem);
1544 } else {
1545 /* Normal timeout if the gettime was successful */
1546 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1547 ret = sem_timedwait(&consumer_data->sem, &timeout);
1548 }
1549
1550 if (ret < 0) {
1551 if (errno == ETIMEDOUT) {
1552 /*
1553 * Call has timed out so we kill the kconsumerd_thread and return
1554 * an error.
1555 */
1556 ERR("The consumer thread was never ready. Killing it");
1557 ret = pthread_cancel(consumer_data->thread);
1558 if (ret < 0) {
1559 PERROR("pthread_cancel consumer thread");
1560 }
1561 } else {
1562 PERROR("semaphore wait failed consumer thread");
1563 }
1564 goto error;
1565 }
1566
1567 pthread_mutex_lock(&consumer_data->pid_mutex);
1568 if (consumer_data->pid == 0) {
1569 ERR("Kconsumerd did not start");
1570 pthread_mutex_unlock(&consumer_data->pid_mutex);
1571 goto error;
1572 }
1573 pthread_mutex_unlock(&consumer_data->pid_mutex);
1574
1575 return 0;
1576
1577 error:
1578 return ret;
1579 }
1580
1581 /*
1582 * Join consumer thread
1583 */
1584 static int join_consumer_thread(struct consumer_data *consumer_data)
1585 {
1586 void *status;
1587 int ret;
1588
1589 if (consumer_data->pid != 0) {
1590 ret = kill(consumer_data->pid, SIGTERM);
1591 if (ret) {
1592 ERR("Error killing consumer daemon");
1593 return ret;
1594 }
1595 return pthread_join(consumer_data->thread, &status);
1596 } else {
1597 return 0;
1598 }
1599 }
1600
1601 /*
1602 * Fork and exec a consumer daemon (consumerd).
1603 *
1604 * Return pid if successful else -1.
1605 */
1606 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1607 {
1608 int ret;
1609 pid_t pid;
1610 const char *consumer_to_use;
1611 const char *verbosity;
1612 struct stat st;
1613
1614 DBG("Spawning consumerd");
1615
1616 pid = fork();
1617 if (pid == 0) {
1618 /*
1619 * Exec consumerd.
1620 */
1621 if (opt_verbose_consumer) {
1622 verbosity = "--verbose";
1623 } else {
1624 verbosity = "--quiet";
1625 }
1626 switch (consumer_data->type) {
1627 case LTTNG_CONSUMER_KERNEL:
1628 /*
1629 * Find out which consumerd to execute. We will first try the
1630 * 64-bit path, then the sessiond's installation directory, and
1631 * fallback on the 32-bit one,
1632 */
1633 DBG3("Looking for a kernel consumer at these locations:");
1634 DBG3(" 1) %s", consumerd64_bin);
1635 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1636 DBG3(" 3) %s", consumerd32_bin);
1637 if (stat(consumerd64_bin, &st) == 0) {
1638 DBG3("Found location #1");
1639 consumer_to_use = consumerd64_bin;
1640 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1641 DBG3("Found location #2");
1642 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1643 } else if (stat(consumerd32_bin, &st) == 0) {
1644 DBG3("Found location #3");
1645 consumer_to_use = consumerd32_bin;
1646 } else {
1647 DBG("Could not find any valid consumerd executable");
1648 break;
1649 }
1650 DBG("Using kernel consumer at: %s", consumer_to_use);
1651 execl(consumer_to_use,
1652 "lttng-consumerd", verbosity, "-k",
1653 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1654 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1655 NULL);
1656 break;
1657 case LTTNG_CONSUMER64_UST:
1658 {
1659 char *tmpnew = NULL;
1660
1661 if (consumerd64_libdir[0] != '\0') {
1662 char *tmp;
1663 size_t tmplen;
1664
1665 tmp = getenv("LD_LIBRARY_PATH");
1666 if (!tmp) {
1667 tmp = "";
1668 }
1669 tmplen = strlen("LD_LIBRARY_PATH=")
1670 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1671 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1672 if (!tmpnew) {
1673 ret = -ENOMEM;
1674 goto error;
1675 }
1676 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1677 strcat(tmpnew, consumerd64_libdir);
1678 if (tmp[0] != '\0') {
1679 strcat(tmpnew, ":");
1680 strcat(tmpnew, tmp);
1681 }
1682 ret = putenv(tmpnew);
1683 if (ret) {
1684 ret = -errno;
1685 goto error;
1686 }
1687 }
1688 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1689 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1690 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1691 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1692 NULL);
1693 if (consumerd64_libdir[0] != '\0') {
1694 free(tmpnew);
1695 }
1696 if (ret) {
1697 goto error;
1698 }
1699 break;
1700 }
1701 case LTTNG_CONSUMER32_UST:
1702 {
1703 char *tmpnew = NULL;
1704
1705 if (consumerd32_libdir[0] != '\0') {
1706 char *tmp;
1707 size_t tmplen;
1708
1709 tmp = getenv("LD_LIBRARY_PATH");
1710 if (!tmp) {
1711 tmp = "";
1712 }
1713 tmplen = strlen("LD_LIBRARY_PATH=")
1714 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1715 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1716 if (!tmpnew) {
1717 ret = -ENOMEM;
1718 goto error;
1719 }
1720 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1721 strcat(tmpnew, consumerd32_libdir);
1722 if (tmp[0] != '\0') {
1723 strcat(tmpnew, ":");
1724 strcat(tmpnew, tmp);
1725 }
1726 ret = putenv(tmpnew);
1727 if (ret) {
1728 ret = -errno;
1729 goto error;
1730 }
1731 }
1732 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1733 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1734 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1735 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1736 NULL);
1737 if (consumerd32_libdir[0] != '\0') {
1738 free(tmpnew);
1739 }
1740 if (ret) {
1741 goto error;
1742 }
1743 break;
1744 }
1745 default:
1746 PERROR("unknown consumer type");
1747 exit(EXIT_FAILURE);
1748 }
1749 if (errno != 0) {
1750 PERROR("kernel start consumer exec");
1751 }
1752 exit(EXIT_FAILURE);
1753 } else if (pid > 0) {
1754 ret = pid;
1755 } else {
1756 PERROR("start consumer fork");
1757 ret = -errno;
1758 }
1759 error:
1760 return ret;
1761 }
1762
1763 /*
1764 * Spawn the consumerd daemon and session daemon thread.
1765 */
1766 static int start_consumerd(struct consumer_data *consumer_data)
1767 {
1768 int ret;
1769
1770 pthread_mutex_lock(&consumer_data->pid_mutex);
1771 if (consumer_data->pid != 0) {
1772 pthread_mutex_unlock(&consumer_data->pid_mutex);
1773 goto end;
1774 }
1775
1776 ret = spawn_consumerd(consumer_data);
1777 if (ret < 0) {
1778 ERR("Spawning consumerd failed");
1779 pthread_mutex_unlock(&consumer_data->pid_mutex);
1780 goto error;
1781 }
1782
1783 /* Setting up the consumer_data pid */
1784 consumer_data->pid = ret;
1785 DBG2("Consumer pid %d", consumer_data->pid);
1786 pthread_mutex_unlock(&consumer_data->pid_mutex);
1787
1788 DBG2("Spawning consumer control thread");
1789 ret = spawn_consumer_thread(consumer_data);
1790 if (ret < 0) {
1791 ERR("Fatal error spawning consumer control thread");
1792 goto error;
1793 }
1794
1795 end:
1796 return 0;
1797
1798 error:
1799 return ret;
1800 }
1801
1802 /*
1803 * Check version of the lttng-modules.
1804 */
1805 static int validate_lttng_modules_version(void)
1806 {
1807 return kernel_validate_version(kernel_tracer_fd);
1808 }
1809
1810 /*
1811 * Setup necessary data for kernel tracer action.
1812 */
1813 static int init_kernel_tracer(void)
1814 {
1815 int ret;
1816
1817 /* Modprobe lttng kernel modules */
1818 ret = modprobe_lttng_control();
1819 if (ret < 0) {
1820 goto error;
1821 }
1822
1823 /* Open debugfs lttng */
1824 kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
1825 if (kernel_tracer_fd < 0) {
1826 DBG("Failed to open %s", module_proc_lttng);
1827 ret = -1;
1828 goto error_open;
1829 }
1830
1831 /* Validate kernel version */
1832 ret = validate_lttng_modules_version();
1833 if (ret < 0) {
1834 goto error_version;
1835 }
1836
1837 ret = modprobe_lttng_data();
1838 if (ret < 0) {
1839 goto error_modules;
1840 }
1841
1842 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1843 return 0;
1844
1845 error_version:
1846 modprobe_remove_lttng_control();
1847 ret = close(kernel_tracer_fd);
1848 if (ret) {
1849 PERROR("close");
1850 }
1851 kernel_tracer_fd = -1;
1852 return LTTCOMM_KERN_VERSION;
1853
1854 error_modules:
1855 ret = close(kernel_tracer_fd);
1856 if (ret) {
1857 PERROR("close");
1858 }
1859
1860 error_open:
1861 modprobe_remove_lttng_control();
1862
1863 error:
1864 WARN("No kernel tracer available");
1865 kernel_tracer_fd = -1;
1866 if (!is_root) {
1867 return LTTCOMM_NEED_ROOT_SESSIOND;
1868 } else {
1869 return LTTCOMM_KERN_NA;
1870 }
1871 }
1872
1873 /*
1874 * Init tracing by creating trace directory and sending fds kernel consumer.
1875 */
1876 static int init_kernel_tracing(struct ltt_kernel_session *session)
1877 {
1878 int ret = 0;
1879
1880 if (session->consumer_fds_sent == 0) {
1881 /*
1882 * Assign default kernel consumer socket if no consumer assigned to the
1883 * kernel session. At this point, it's NOT supposed to be -1 but this is
1884 * an extra security check.
1885 */
1886 if (session->consumer_fd < 0) {
1887 session->consumer_fd = kconsumer_data.cmd_sock;
1888 }
1889
1890 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1891 if (ret < 0) {
1892 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1893 goto error;
1894 }
1895
1896 session->consumer_fds_sent = 1;
1897 }
1898
1899 error:
1900 return ret;
1901 }
1902
1903 /*
1904 * Create an UST session and add it to the session ust list.
1905 */
1906 static int create_ust_session(struct ltt_session *session,
1907 struct lttng_domain *domain)
1908 {
1909 struct ltt_ust_session *lus = NULL;
1910 int ret;
1911
1912 switch (domain->type) {
1913 case LTTNG_DOMAIN_UST:
1914 break;
1915 default:
1916 ret = LTTCOMM_UNKNOWN_DOMAIN;
1917 goto error;
1918 }
1919
1920 DBG("Creating UST session");
1921
1922 lus = trace_ust_create_session(session->path, session->id, domain);
1923 if (lus == NULL) {
1924 ret = LTTCOMM_UST_SESS_FAIL;
1925 goto error;
1926 }
1927
1928 ret = run_as_mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1929 session->uid, session->gid);
1930 if (ret < 0) {
1931 if (ret != -EEXIST) {
1932 ERR("Trace directory creation error");
1933 ret = LTTCOMM_UST_SESS_FAIL;
1934 goto error;
1935 }
1936 }
1937
1938 /* The domain type dictate different actions on session creation */
1939 switch (domain->type) {
1940 case LTTNG_DOMAIN_UST:
1941 /* No ustctl for the global UST domain */
1942 break;
1943 default:
1944 ERR("Unknown UST domain on create session %d", domain->type);
1945 goto error;
1946 }
1947 lus->uid = session->uid;
1948 lus->gid = session->gid;
1949 session->ust_session = lus;
1950
1951 return LTTCOMM_OK;
1952
1953 error:
1954 free(lus);
1955 return ret;
1956 }
1957
1958 /*
1959 * Create a kernel tracer session then create the default channel.
1960 */
1961 static int create_kernel_session(struct ltt_session *session)
1962 {
1963 int ret;
1964
1965 DBG("Creating kernel session");
1966
1967 ret = kernel_create_session(session, kernel_tracer_fd);
1968 if (ret < 0) {
1969 ret = LTTCOMM_KERN_SESS_FAIL;
1970 goto error;
1971 }
1972
1973 /* Set kernel consumer socket fd */
1974 if (kconsumer_data.cmd_sock >= 0) {
1975 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1976 }
1977
1978 ret = run_as_mkdir_recursive(session->kernel_session->trace_path,
1979 S_IRWXU | S_IRWXG, session->uid, session->gid);
1980 if (ret < 0) {
1981 if (ret != -EEXIST) {
1982 ERR("Trace directory creation error");
1983 goto error;
1984 }
1985 }
1986 session->kernel_session->uid = session->uid;
1987 session->kernel_session->gid = session->gid;
1988
1989 error:
1990 return ret;
1991 }
1992
1993 /*
1994 * Check if the UID or GID match the session. Root user has access to all
1995 * sessions.
1996 */
1997 static int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid)
1998 {
1999 if (uid != session->uid && gid != session->gid && uid != 0) {
2000 return 0;
2001 } else {
2002 return 1;
2003 }
2004 }
2005
2006 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
2007 {
2008 unsigned int i = 0;
2009 struct ltt_session *session;
2010
2011 DBG("Counting number of available session for UID %d GID %d",
2012 uid, gid);
2013 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2014 /*
2015 * Only list the sessions the user can control.
2016 */
2017 if (!session_access_ok(session, uid, gid)) {
2018 continue;
2019 }
2020 i++;
2021 }
2022 return i;
2023 }
2024
2025 /*
2026 * Using the session list, filled a lttng_session array to send back to the
2027 * client for session listing.
2028 *
2029 * The session list lock MUST be acquired before calling this function. Use
2030 * session_lock_list() and session_unlock_list().
2031 */
2032 static void list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2033 gid_t gid)
2034 {
2035 unsigned int i = 0;
2036 struct ltt_session *session;
2037
2038 DBG("Getting all available session for UID %d GID %d",
2039 uid, gid);
2040 /*
2041 * Iterate over session list and append data after the control struct in
2042 * the buffer.
2043 */
2044 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2045 /*
2046 * Only list the sessions the user can control.
2047 */
2048 if (!session_access_ok(session, uid, gid)) {
2049 continue;
2050 }
2051 strncpy(sessions[i].path, session->path, PATH_MAX);
2052 sessions[i].path[PATH_MAX - 1] = '\0';
2053 strncpy(sessions[i].name, session->name, NAME_MAX);
2054 sessions[i].name[NAME_MAX - 1] = '\0';
2055 sessions[i].enabled = session->enabled;
2056 i++;
2057 }
2058 }
2059
2060 /*
2061 * Fill lttng_channel array of all channels.
2062 */
2063 static void list_lttng_channels(int domain, struct ltt_session *session,
2064 struct lttng_channel *channels)
2065 {
2066 int i = 0;
2067 struct ltt_kernel_channel *kchan;
2068
2069 DBG("Listing channels for session %s", session->name);
2070
2071 switch (domain) {
2072 case LTTNG_DOMAIN_KERNEL:
2073 /* Kernel channels */
2074 if (session->kernel_session != NULL) {
2075 cds_list_for_each_entry(kchan,
2076 &session->kernel_session->channel_list.head, list) {
2077 /* Copy lttng_channel struct to array */
2078 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2079 channels[i].enabled = kchan->enabled;
2080 i++;
2081 }
2082 }
2083 break;
2084 case LTTNG_DOMAIN_UST:
2085 {
2086 struct lttng_ht_iter iter;
2087 struct ltt_ust_channel *uchan;
2088
2089 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
2090 &iter.iter, uchan, node.node) {
2091 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2092 channels[i].attr.overwrite = uchan->attr.overwrite;
2093 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2094 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2095 channels[i].attr.switch_timer_interval =
2096 uchan->attr.switch_timer_interval;
2097 channels[i].attr.read_timer_interval =
2098 uchan->attr.read_timer_interval;
2099 channels[i].enabled = uchan->enabled;
2100 switch (uchan->attr.output) {
2101 case LTTNG_UST_MMAP:
2102 default:
2103 channels[i].attr.output = LTTNG_EVENT_MMAP;
2104 break;
2105 }
2106 i++;
2107 }
2108 break;
2109 }
2110 default:
2111 break;
2112 }
2113 }
2114
2115 /*
2116 * Create a list of ust global domain events.
2117 */
2118 static int list_lttng_ust_global_events(char *channel_name,
2119 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2120 {
2121 int i = 0, ret = 0;
2122 unsigned int nb_event = 0;
2123 struct lttng_ht_iter iter;
2124 struct lttng_ht_node_str *node;
2125 struct ltt_ust_channel *uchan;
2126 struct ltt_ust_event *uevent;
2127 struct lttng_event *tmp;
2128
2129 DBG("Listing UST global events for channel %s", channel_name);
2130
2131 rcu_read_lock();
2132
2133 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2134 node = lttng_ht_iter_get_node_str(&iter);
2135 if (node == NULL) {
2136 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2137 goto error;
2138 }
2139
2140 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2141
2142 nb_event += lttng_ht_get_count(uchan->events);
2143
2144 if (nb_event == 0) {
2145 ret = nb_event;
2146 goto error;
2147 }
2148
2149 DBG3("Listing UST global %d events", nb_event);
2150
2151 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2152 if (tmp == NULL) {
2153 ret = -LTTCOMM_FATAL;
2154 goto error;
2155 }
2156
2157 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2158 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2159 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2160 tmp[i].enabled = uevent->enabled;
2161 switch (uevent->attr.instrumentation) {
2162 case LTTNG_UST_TRACEPOINT:
2163 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2164 break;
2165 case LTTNG_UST_PROBE:
2166 tmp[i].type = LTTNG_EVENT_PROBE;
2167 break;
2168 case LTTNG_UST_FUNCTION:
2169 tmp[i].type = LTTNG_EVENT_FUNCTION;
2170 break;
2171 }
2172 tmp[i].loglevel = uevent->attr.loglevel;
2173 switch (uevent->attr.loglevel_type) {
2174 case LTTNG_UST_LOGLEVEL_ALL:
2175 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2176 break;
2177 case LTTNG_UST_LOGLEVEL_RANGE:
2178 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
2179 break;
2180 case LTTNG_UST_LOGLEVEL_SINGLE:
2181 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
2182 break;
2183 }
2184 i++;
2185 }
2186
2187 ret = nb_event;
2188 *events = tmp;
2189
2190 error:
2191 rcu_read_unlock();
2192 return ret;
2193 }
2194
2195 /*
2196 * Fill lttng_event array of all kernel events in the channel.
2197 */
2198 static int list_lttng_kernel_events(char *channel_name,
2199 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2200 {
2201 int i = 0, ret;
2202 unsigned int nb_event;
2203 struct ltt_kernel_event *event;
2204 struct ltt_kernel_channel *kchan;
2205
2206 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2207 if (kchan == NULL) {
2208 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2209 goto error;
2210 }
2211
2212 nb_event = kchan->event_count;
2213
2214 DBG("Listing events for channel %s", kchan->channel->name);
2215
2216 if (nb_event == 0) {
2217 ret = nb_event;
2218 goto error;
2219 }
2220
2221 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2222 if (*events == NULL) {
2223 ret = LTTCOMM_FATAL;
2224 goto error;
2225 }
2226
2227 /* Kernel channels */
2228 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2229 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2230 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2231 (*events)[i].enabled = event->enabled;
2232 switch (event->event->instrumentation) {
2233 case LTTNG_KERNEL_TRACEPOINT:
2234 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2235 break;
2236 case LTTNG_KERNEL_KPROBE:
2237 case LTTNG_KERNEL_KRETPROBE:
2238 (*events)[i].type = LTTNG_EVENT_PROBE;
2239 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2240 sizeof(struct lttng_kernel_kprobe));
2241 break;
2242 case LTTNG_KERNEL_FUNCTION:
2243 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2244 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2245 sizeof(struct lttng_kernel_function));
2246 break;
2247 case LTTNG_KERNEL_NOOP:
2248 (*events)[i].type = LTTNG_EVENT_NOOP;
2249 break;
2250 case LTTNG_KERNEL_SYSCALL:
2251 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2252 break;
2253 case LTTNG_KERNEL_ALL:
2254 assert(0);
2255 break;
2256 }
2257 i++;
2258 }
2259
2260 return nb_event;
2261
2262 error:
2263 return ret;
2264 }
2265
2266 /*
2267 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2268 */
2269 static int cmd_disable_channel(struct ltt_session *session,
2270 int domain, char *channel_name)
2271 {
2272 int ret;
2273 struct ltt_ust_session *usess;
2274
2275 usess = session->ust_session;
2276
2277 switch (domain) {
2278 case LTTNG_DOMAIN_KERNEL:
2279 {
2280 ret = channel_kernel_disable(session->kernel_session,
2281 channel_name);
2282 if (ret != LTTCOMM_OK) {
2283 goto error;
2284 }
2285
2286 kernel_wait_quiescent(kernel_tracer_fd);
2287 break;
2288 }
2289 case LTTNG_DOMAIN_UST:
2290 {
2291 struct ltt_ust_channel *uchan;
2292 struct lttng_ht *chan_ht;
2293
2294 chan_ht = usess->domain_global.channels;
2295
2296 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2297 if (uchan == NULL) {
2298 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2299 goto error;
2300 }
2301
2302 ret = channel_ust_disable(usess, domain, uchan);
2303 if (ret != LTTCOMM_OK) {
2304 goto error;
2305 }
2306 break;
2307 }
2308 #if 0
2309 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2310 case LTTNG_DOMAIN_UST_EXEC_NAME:
2311 case LTTNG_DOMAIN_UST_PID:
2312 #endif
2313 default:
2314 ret = LTTCOMM_UNKNOWN_DOMAIN;
2315 goto error;
2316 }
2317
2318 ret = LTTCOMM_OK;
2319
2320 error:
2321 return ret;
2322 }
2323
2324 /*
2325 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2326 */
2327 static int cmd_enable_channel(struct ltt_session *session,
2328 int domain, struct lttng_channel *attr)
2329 {
2330 int ret;
2331 struct ltt_ust_session *usess = session->ust_session;
2332 struct lttng_ht *chan_ht;
2333
2334 DBG("Enabling channel %s for session %s", attr->name, session->name);
2335
2336 switch (domain) {
2337 case LTTNG_DOMAIN_KERNEL:
2338 {
2339 struct ltt_kernel_channel *kchan;
2340
2341 kchan = trace_kernel_get_channel_by_name(attr->name,
2342 session->kernel_session);
2343 if (kchan == NULL) {
2344 ret = channel_kernel_create(session->kernel_session,
2345 attr, kernel_poll_pipe[1]);
2346 } else {
2347 ret = channel_kernel_enable(session->kernel_session, kchan);
2348 }
2349
2350 if (ret != LTTCOMM_OK) {
2351 goto error;
2352 }
2353
2354 kernel_wait_quiescent(kernel_tracer_fd);
2355 break;
2356 }
2357 case LTTNG_DOMAIN_UST:
2358 {
2359 struct ltt_ust_channel *uchan;
2360
2361 chan_ht = usess->domain_global.channels;
2362
2363 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2364 if (uchan == NULL) {
2365 ret = channel_ust_create(usess, domain, attr);
2366 } else {
2367 ret = channel_ust_enable(usess, domain, uchan);
2368 }
2369 break;
2370 }
2371 #if 0
2372 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2373 case LTTNG_DOMAIN_UST_EXEC_NAME:
2374 case LTTNG_DOMAIN_UST_PID:
2375 #endif
2376 default:
2377 ret = LTTCOMM_UNKNOWN_DOMAIN;
2378 goto error;
2379 }
2380
2381 error:
2382 return ret;
2383 }
2384
2385 /*
2386 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2387 */
2388 static int cmd_disable_event(struct ltt_session *session, int domain,
2389 char *channel_name, char *event_name)
2390 {
2391 int ret;
2392
2393 switch (domain) {
2394 case LTTNG_DOMAIN_KERNEL:
2395 {
2396 struct ltt_kernel_channel *kchan;
2397 struct ltt_kernel_session *ksess;
2398
2399 ksess = session->kernel_session;
2400
2401 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2402 if (kchan == NULL) {
2403 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2404 goto error;
2405 }
2406
2407 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2408 if (ret != LTTCOMM_OK) {
2409 goto error;
2410 }
2411
2412 kernel_wait_quiescent(kernel_tracer_fd);
2413 break;
2414 }
2415 case LTTNG_DOMAIN_UST:
2416 {
2417 struct ltt_ust_channel *uchan;
2418 struct ltt_ust_session *usess;
2419
2420 usess = session->ust_session;
2421
2422 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2423 channel_name);
2424 if (uchan == NULL) {
2425 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2426 goto error;
2427 }
2428
2429 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2430 if (ret != LTTCOMM_OK) {
2431 goto error;
2432 }
2433
2434 DBG3("Disable UST event %s in channel %s completed", event_name,
2435 channel_name);
2436 break;
2437 }
2438 #if 0
2439 case LTTNG_DOMAIN_UST_EXEC_NAME:
2440 case LTTNG_DOMAIN_UST_PID:
2441 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2442 #endif
2443 default:
2444 ret = LTTCOMM_UND;
2445 goto error;
2446 }
2447
2448 ret = LTTCOMM_OK;
2449
2450 error:
2451 return ret;
2452 }
2453
2454 /*
2455 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2456 */
2457 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2458 char *channel_name)
2459 {
2460 int ret;
2461
2462 switch (domain) {
2463 case LTTNG_DOMAIN_KERNEL:
2464 {
2465 struct ltt_kernel_session *ksess;
2466 struct ltt_kernel_channel *kchan;
2467
2468 ksess = session->kernel_session;
2469
2470 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2471 if (kchan == NULL) {
2472 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2473 goto error;
2474 }
2475
2476 ret = event_kernel_disable_all(ksess, kchan);
2477 if (ret != LTTCOMM_OK) {
2478 goto error;
2479 }
2480
2481 kernel_wait_quiescent(kernel_tracer_fd);
2482 break;
2483 }
2484 case LTTNG_DOMAIN_UST:
2485 {
2486 struct ltt_ust_session *usess;
2487 struct ltt_ust_channel *uchan;
2488
2489 usess = session->ust_session;
2490
2491 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2492 channel_name);
2493 if (uchan == NULL) {
2494 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2495 goto error;
2496 }
2497
2498 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2499 if (ret != 0) {
2500 goto error;
2501 }
2502
2503 DBG3("Disable all UST events in channel %s completed", channel_name);
2504
2505 break;
2506 }
2507 #if 0
2508 case LTTNG_DOMAIN_UST_EXEC_NAME:
2509 case LTTNG_DOMAIN_UST_PID:
2510 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2511 #endif
2512 default:
2513 ret = LTTCOMM_UND;
2514 goto error;
2515 }
2516
2517 ret = LTTCOMM_OK;
2518
2519 error:
2520 return ret;
2521 }
2522
2523 /*
2524 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2525 */
2526 static int cmd_add_context(struct ltt_session *session, int domain,
2527 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2528 {
2529 int ret;
2530
2531 switch (domain) {
2532 case LTTNG_DOMAIN_KERNEL:
2533 /* Add kernel context to kernel tracer */
2534 ret = context_kernel_add(session->kernel_session, ctx,
2535 event_name, channel_name);
2536 if (ret != LTTCOMM_OK) {
2537 goto error;
2538 }
2539 break;
2540 case LTTNG_DOMAIN_UST:
2541 {
2542 struct ltt_ust_session *usess = session->ust_session;
2543
2544 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2545 if (ret != LTTCOMM_OK) {
2546 goto error;
2547 }
2548 break;
2549 }
2550 #if 0
2551 case LTTNG_DOMAIN_UST_EXEC_NAME:
2552 case LTTNG_DOMAIN_UST_PID:
2553 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2554 #endif
2555 default:
2556 ret = LTTCOMM_UND;
2557 goto error;
2558 }
2559
2560 ret = LTTCOMM_OK;
2561
2562 error:
2563 return ret;
2564 }
2565
2566 /*
2567 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2568 */
2569 static int cmd_enable_event(struct ltt_session *session, int domain,
2570 char *channel_name, struct lttng_event *event)
2571 {
2572 int ret;
2573 struct lttng_channel *attr;
2574 struct ltt_ust_session *usess = session->ust_session;
2575
2576 switch (domain) {
2577 case LTTNG_DOMAIN_KERNEL:
2578 {
2579 struct ltt_kernel_channel *kchan;
2580
2581 kchan = trace_kernel_get_channel_by_name(channel_name,
2582 session->kernel_session);
2583 if (kchan == NULL) {
2584 attr = channel_new_default_attr(domain);
2585 if (attr == NULL) {
2586 ret = LTTCOMM_FATAL;
2587 goto error;
2588 }
2589 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2590
2591 /* This call will notify the kernel thread */
2592 ret = channel_kernel_create(session->kernel_session,
2593 attr, kernel_poll_pipe[1]);
2594 if (ret != LTTCOMM_OK) {
2595 free(attr);
2596 goto error;
2597 }
2598 free(attr);
2599 }
2600
2601 /* Get the newly created kernel channel pointer */
2602 kchan = trace_kernel_get_channel_by_name(channel_name,
2603 session->kernel_session);
2604 if (kchan == NULL) {
2605 /* This sould not happen... */
2606 ret = LTTCOMM_FATAL;
2607 goto error;
2608 }
2609
2610 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2611 event);
2612 if (ret != LTTCOMM_OK) {
2613 goto error;
2614 }
2615
2616 kernel_wait_quiescent(kernel_tracer_fd);
2617 break;
2618 }
2619 case LTTNG_DOMAIN_UST:
2620 {
2621 struct lttng_channel *attr;
2622 struct ltt_ust_channel *uchan;
2623
2624 /* Get channel from global UST domain */
2625 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2626 channel_name);
2627 if (uchan == NULL) {
2628 /* Create default channel */
2629 attr = channel_new_default_attr(domain);
2630 if (attr == NULL) {
2631 ret = LTTCOMM_FATAL;
2632 goto error;
2633 }
2634 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2635 attr->name[NAME_MAX - 1] = '\0';
2636
2637 ret = channel_ust_create(usess, domain, attr);
2638 if (ret != LTTCOMM_OK) {
2639 free(attr);
2640 goto error;
2641 }
2642 free(attr);
2643
2644 /* Get the newly created channel reference back */
2645 uchan = trace_ust_find_channel_by_name(
2646 usess->domain_global.channels, channel_name);
2647 if (uchan == NULL) {
2648 /* Something is really wrong */
2649 ret = LTTCOMM_FATAL;
2650 goto error;
2651 }
2652 }
2653
2654 /* At this point, the session and channel exist on the tracer */
2655 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2656 if (ret != LTTCOMM_OK) {
2657 goto error;
2658 }
2659 break;
2660 }
2661 #if 0
2662 case LTTNG_DOMAIN_UST_EXEC_NAME:
2663 case LTTNG_DOMAIN_UST_PID:
2664 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2665 #endif
2666 default:
2667 ret = LTTCOMM_UND;
2668 goto error;
2669 }
2670
2671 ret = LTTCOMM_OK;
2672
2673 error:
2674 return ret;
2675 }
2676
2677 /*
2678 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2679 */
2680 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2681 char *channel_name, int event_type)
2682 {
2683 int ret;
2684 struct ltt_kernel_channel *kchan;
2685
2686 switch (domain) {
2687 case LTTNG_DOMAIN_KERNEL:
2688 kchan = trace_kernel_get_channel_by_name(channel_name,
2689 session->kernel_session);
2690 if (kchan == NULL) {
2691 /* This call will notify the kernel thread */
2692 ret = channel_kernel_create(session->kernel_session, NULL,
2693 kernel_poll_pipe[1]);
2694 if (ret != LTTCOMM_OK) {
2695 goto error;
2696 }
2697
2698 /* Get the newly created kernel channel pointer */
2699 kchan = trace_kernel_get_channel_by_name(channel_name,
2700 session->kernel_session);
2701 if (kchan == NULL) {
2702 /* This sould not happen... */
2703 ret = LTTCOMM_FATAL;
2704 goto error;
2705 }
2706
2707 }
2708
2709 switch (event_type) {
2710 case LTTNG_EVENT_SYSCALL:
2711 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2712 kchan, kernel_tracer_fd);
2713 break;
2714 case LTTNG_EVENT_TRACEPOINT:
2715 /*
2716 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2717 * events already registered to the channel.
2718 */
2719 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2720 kchan, kernel_tracer_fd);
2721 break;
2722 case LTTNG_EVENT_ALL:
2723 /* Enable syscalls and tracepoints */
2724 ret = event_kernel_enable_all(session->kernel_session,
2725 kchan, kernel_tracer_fd);
2726 break;
2727 default:
2728 ret = LTTCOMM_KERN_ENABLE_FAIL;
2729 goto error;
2730 }
2731
2732 /* Manage return value */
2733 if (ret != LTTCOMM_OK) {
2734 goto error;
2735 }
2736
2737 kernel_wait_quiescent(kernel_tracer_fd);
2738 break;
2739 case LTTNG_DOMAIN_UST:
2740 {
2741 struct lttng_channel *attr;
2742 struct ltt_ust_channel *uchan;
2743 struct ltt_ust_session *usess = session->ust_session;
2744
2745 /* Get channel from global UST domain */
2746 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2747 channel_name);
2748 if (uchan == NULL) {
2749 /* Create default channel */
2750 attr = channel_new_default_attr(domain);
2751 if (attr == NULL) {
2752 ret = LTTCOMM_FATAL;
2753 goto error;
2754 }
2755 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2756 attr->name[NAME_MAX - 1] = '\0';
2757
2758 /* Use the internal command enable channel */
2759 ret = channel_ust_create(usess, domain, attr);
2760 if (ret != LTTCOMM_OK) {
2761 free(attr);
2762 goto error;
2763 }
2764 free(attr);
2765
2766 /* Get the newly created channel reference back */
2767 uchan = trace_ust_find_channel_by_name(
2768 usess->domain_global.channels, channel_name);
2769 if (uchan == NULL) {
2770 /* Something is really wrong */
2771 ret = LTTCOMM_FATAL;
2772 goto error;
2773 }
2774 }
2775
2776 /* At this point, the session and channel exist on the tracer */
2777
2778 switch (event_type) {
2779 case LTTNG_EVENT_ALL:
2780 case LTTNG_EVENT_TRACEPOINT:
2781 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2782 if (ret != LTTCOMM_OK) {
2783 goto error;
2784 }
2785 break;
2786 default:
2787 ret = LTTCOMM_UST_ENABLE_FAIL;
2788 goto error;
2789 }
2790
2791 /* Manage return value */
2792 if (ret != LTTCOMM_OK) {
2793 goto error;
2794 }
2795
2796 break;
2797 }
2798 #if 0
2799 case LTTNG_DOMAIN_UST_EXEC_NAME:
2800 case LTTNG_DOMAIN_UST_PID:
2801 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2802 #endif
2803 default:
2804 ret = LTTCOMM_UND;
2805 goto error;
2806 }
2807
2808 ret = LTTCOMM_OK;
2809
2810 error:
2811 return ret;
2812 }
2813
2814 /*
2815 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2816 */
2817 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2818 {
2819 int ret;
2820 ssize_t nb_events = 0;
2821
2822 switch (domain) {
2823 case LTTNG_DOMAIN_KERNEL:
2824 nb_events = kernel_list_events(kernel_tracer_fd, events);
2825 if (nb_events < 0) {
2826 ret = LTTCOMM_KERN_LIST_FAIL;
2827 goto error;
2828 }
2829 break;
2830 case LTTNG_DOMAIN_UST:
2831 nb_events = ust_app_list_events(events);
2832 if (nb_events < 0) {
2833 ret = LTTCOMM_UST_LIST_FAIL;
2834 goto error;
2835 }
2836 break;
2837 default:
2838 ret = LTTCOMM_UND;
2839 goto error;
2840 }
2841
2842 return nb_events;
2843
2844 error:
2845 /* Return negative value to differentiate return code */
2846 return -ret;
2847 }
2848
2849 /*
2850 * Command LTTNG_START_TRACE processed by the client thread.
2851 */
2852 static int cmd_start_trace(struct ltt_session *session)
2853 {
2854 int ret;
2855 struct ltt_kernel_session *ksession;
2856 struct ltt_ust_session *usess;
2857
2858 /* Short cut */
2859 ksession = session->kernel_session;
2860 usess = session->ust_session;
2861
2862 if (session->enabled) {
2863 /* Already started. */
2864 ret = LTTCOMM_TRACE_ALREADY_STARTED;
2865 goto error;
2866 }
2867
2868 session->enabled = 1;
2869
2870 /* Kernel tracing */
2871 if (ksession != NULL) {
2872 struct ltt_kernel_channel *kchan;
2873
2874 /* Open kernel metadata */
2875 if (ksession->metadata == NULL) {
2876 ret = kernel_open_metadata(ksession, ksession->trace_path);
2877 if (ret < 0) {
2878 ret = LTTCOMM_KERN_META_FAIL;
2879 goto error;
2880 }
2881 }
2882
2883 /* Open kernel metadata stream */
2884 if (ksession->metadata_stream_fd < 0) {
2885 ret = kernel_open_metadata_stream(ksession);
2886 if (ret < 0) {
2887 ERR("Kernel create metadata stream failed");
2888 ret = LTTCOMM_KERN_STREAM_FAIL;
2889 goto error;
2890 }
2891 }
2892
2893 /* For each channel */
2894 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2895 if (kchan->stream_count == 0) {
2896 ret = kernel_open_channel_stream(kchan);
2897 if (ret < 0) {
2898 ret = LTTCOMM_KERN_STREAM_FAIL;
2899 goto error;
2900 }
2901 /* Update the stream global counter */
2902 ksession->stream_count_global += ret;
2903 }
2904 }
2905
2906 /* Setup kernel consumer socket and send fds to it */
2907 ret = init_kernel_tracing(ksession);
2908 if (ret < 0) {
2909 ret = LTTCOMM_KERN_START_FAIL;
2910 goto error;
2911 }
2912
2913 /* This start the kernel tracing */
2914 ret = kernel_start_session(ksession);
2915 if (ret < 0) {
2916 ret = LTTCOMM_KERN_START_FAIL;
2917 goto error;
2918 }
2919
2920 /* Quiescent wait after starting trace */
2921 kernel_wait_quiescent(kernel_tracer_fd);
2922 }
2923
2924 /* Flag session that trace should start automatically */
2925 if (usess) {
2926 usess->start_trace = 1;
2927
2928 ret = ust_app_start_trace_all(usess);
2929 if (ret < 0) {
2930 ret = LTTCOMM_UST_START_FAIL;
2931 goto error;
2932 }
2933 }
2934
2935 ret = LTTCOMM_OK;
2936
2937 error:
2938 return ret;
2939 }
2940
2941 /*
2942 * Command LTTNG_STOP_TRACE processed by the client thread.
2943 */
2944 static int cmd_stop_trace(struct ltt_session *session)
2945 {
2946 int ret;
2947 struct ltt_kernel_channel *kchan;
2948 struct ltt_kernel_session *ksession;
2949 struct ltt_ust_session *usess;
2950
2951 /* Short cut */
2952 ksession = session->kernel_session;
2953 usess = session->ust_session;
2954
2955 if (!session->enabled) {
2956 ret = LTTCOMM_TRACE_ALREADY_STOPPED;
2957 goto error;
2958 }
2959
2960 session->enabled = 0;
2961
2962 /* Kernel tracer */
2963 if (ksession != NULL) {
2964 DBG("Stop kernel tracing");
2965
2966 /* Flush all buffers before stopping */
2967 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2968 if (ret < 0) {
2969 ERR("Kernel metadata flush failed");
2970 }
2971
2972 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2973 ret = kernel_flush_buffer(kchan);
2974 if (ret < 0) {
2975 ERR("Kernel flush buffer error");
2976 }
2977 }
2978
2979 ret = kernel_stop_session(ksession);
2980 if (ret < 0) {
2981 ret = LTTCOMM_KERN_STOP_FAIL;
2982 goto error;
2983 }
2984
2985 kernel_wait_quiescent(kernel_tracer_fd);
2986 }
2987
2988 if (usess) {
2989 usess->start_trace = 0;
2990
2991 ret = ust_app_stop_trace_all(usess);
2992 if (ret < 0) {
2993 ret = LTTCOMM_UST_STOP_FAIL;
2994 goto error;
2995 }
2996 }
2997
2998 ret = LTTCOMM_OK;
2999
3000 error:
3001 return ret;
3002 }
3003
3004 /*
3005 * Command LTTNG_CREATE_SESSION processed by the client thread.
3006 */
3007 static int cmd_create_session(char *name, char *path, lttng_sock_cred *creds)
3008 {
3009 int ret;
3010
3011 ret = session_create(name, path, LTTNG_SOCK_GET_UID_CRED(creds),
3012 LTTNG_SOCK_GET_GID_CRED(creds));
3013 if (ret != LTTCOMM_OK) {
3014 goto error;
3015 }
3016
3017 ret = LTTCOMM_OK;
3018
3019 error:
3020 return ret;
3021 }
3022
3023 /*
3024 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3025 */
3026 static int cmd_destroy_session(struct ltt_session *session, char *name)
3027 {
3028 int ret;
3029
3030 /* Clean kernel session teardown */
3031 teardown_kernel_session(session);
3032 /* UST session teardown */
3033 teardown_ust_session(session);
3034
3035 /*
3036 * Must notify the kernel thread here to update it's poll setin order
3037 * to remove the channel(s)' fd just destroyed.
3038 */
3039 ret = notify_thread_pipe(kernel_poll_pipe[1]);
3040 if (ret < 0) {
3041 PERROR("write kernel poll pipe");
3042 }
3043
3044 ret = session_destroy(session);
3045
3046 return ret;
3047 }
3048
3049 /*
3050 * Command LTTNG_CALIBRATE processed by the client thread.
3051 */
3052 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3053 {
3054 int ret;
3055
3056 switch (domain) {
3057 case LTTNG_DOMAIN_KERNEL:
3058 {
3059 struct lttng_kernel_calibrate kcalibrate;
3060
3061 kcalibrate.type = calibrate->type;
3062 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3063 if (ret < 0) {
3064 ret = LTTCOMM_KERN_ENABLE_FAIL;
3065 goto error;
3066 }
3067 break;
3068 }
3069 case LTTNG_DOMAIN_UST:
3070 {
3071 struct lttng_ust_calibrate ucalibrate;
3072
3073 ucalibrate.type = calibrate->type;
3074 ret = ust_app_calibrate_glb(&ucalibrate);
3075 if (ret < 0) {
3076 ret = LTTCOMM_UST_CALIBRATE_FAIL;
3077 goto error;
3078 }
3079 break;
3080 }
3081 default:
3082 ret = LTTCOMM_UND;
3083 goto error;
3084 }
3085
3086 ret = LTTCOMM_OK;
3087
3088 error:
3089 return ret;
3090 }
3091
3092 /*
3093 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3094 */
3095 static int cmd_register_consumer(struct ltt_session *session, int domain,
3096 char *sock_path)
3097 {
3098 int ret, sock;
3099
3100 switch (domain) {
3101 case LTTNG_DOMAIN_KERNEL:
3102 /* Can't register a consumer if there is already one */
3103 if (session->kernel_session->consumer_fds_sent != 0) {
3104 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3105 goto error;
3106 }
3107
3108 sock = lttcomm_connect_unix_sock(sock_path);
3109 if (sock < 0) {
3110 ret = LTTCOMM_CONNECT_FAIL;
3111 goto error;
3112 }
3113
3114 session->kernel_session->consumer_fd = sock;
3115 break;
3116 default:
3117 /* TODO: Userspace tracing */
3118 ret = LTTCOMM_UND;
3119 goto error;
3120 }
3121
3122 ret = LTTCOMM_OK;
3123
3124 error:
3125 return ret;
3126 }
3127
3128 /*
3129 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3130 */
3131 static ssize_t cmd_list_domains(struct ltt_session *session,
3132 struct lttng_domain **domains)
3133 {
3134 int ret, index = 0;
3135 ssize_t nb_dom = 0;
3136
3137 if (session->kernel_session != NULL) {
3138 DBG3("Listing domains found kernel domain");
3139 nb_dom++;
3140 }
3141
3142 if (session->ust_session != NULL) {
3143 DBG3("Listing domains found UST global domain");
3144 nb_dom++;
3145 }
3146
3147 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3148 if (*domains == NULL) {
3149 ret = -LTTCOMM_FATAL;
3150 goto error;
3151 }
3152
3153 if (session->kernel_session != NULL) {
3154 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3155 index++;
3156 }
3157
3158 if (session->ust_session != NULL) {
3159 (*domains)[index].type = LTTNG_DOMAIN_UST;
3160 index++;
3161 }
3162
3163 return nb_dom;
3164
3165 error:
3166 return ret;
3167 }
3168
3169 /*
3170 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3171 */
3172 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3173 struct lttng_channel **channels)
3174 {
3175 int ret;
3176 ssize_t nb_chan = 0;
3177
3178 switch (domain) {
3179 case LTTNG_DOMAIN_KERNEL:
3180 if (session->kernel_session != NULL) {
3181 nb_chan = session->kernel_session->channel_count;
3182 }
3183 DBG3("Number of kernel channels %zd", nb_chan);
3184 break;
3185 case LTTNG_DOMAIN_UST:
3186 if (session->ust_session != NULL) {
3187 nb_chan = lttng_ht_get_count(
3188 session->ust_session->domain_global.channels);
3189 }
3190 DBG3("Number of UST global channels %zd", nb_chan);
3191 break;
3192 default:
3193 *channels = NULL;
3194 ret = -LTTCOMM_UND;
3195 goto error;
3196 }
3197
3198 if (nb_chan > 0) {
3199 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3200 if (*channels == NULL) {
3201 ret = -LTTCOMM_FATAL;
3202 goto error;
3203 }
3204
3205 list_lttng_channels(domain, session, *channels);
3206 } else {
3207 *channels = NULL;
3208 }
3209
3210 return nb_chan;
3211
3212 error:
3213 return ret;
3214 }
3215
3216 /*
3217 * Command LTTNG_LIST_EVENTS processed by the client thread.
3218 */
3219 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3220 char *channel_name, struct lttng_event **events)
3221 {
3222 int ret = 0;
3223 ssize_t nb_event = 0;
3224
3225 switch (domain) {
3226 case LTTNG_DOMAIN_KERNEL:
3227 if (session->kernel_session != NULL) {
3228 nb_event = list_lttng_kernel_events(channel_name,
3229 session->kernel_session, events);
3230 }
3231 break;
3232 case LTTNG_DOMAIN_UST:
3233 {
3234 if (session->ust_session != NULL) {
3235 nb_event = list_lttng_ust_global_events(channel_name,
3236 &session->ust_session->domain_global, events);
3237 }
3238 break;
3239 }
3240 default:
3241 ret = -LTTCOMM_UND;
3242 goto error;
3243 }
3244
3245 ret = nb_event;
3246
3247 error:
3248 return ret;
3249 }
3250
3251 /*
3252 * Process the command requested by the lttng client within the command
3253 * context structure. This function make sure that the return structure (llm)
3254 * is set and ready for transmission before returning.
3255 *
3256 * Return any error encountered or 0 for success.
3257 */
3258 static int process_client_msg(struct command_ctx *cmd_ctx)
3259 {
3260 int ret = LTTCOMM_OK;