Add support for UST enable all tracepoints
[lttng-tools.git] / lttng-sessiond / main.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the Free
7 * Software Foundation; only version 2 of the License.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
16 * Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18
19 #define _GNU_SOURCE
20 #include <fcntl.h>
21 #include <getopt.h>
22 #include <grp.h>
23 #include <limits.h>
24 #include <pthread.h>
25 #include <semaphore.h>
26 #include <signal.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <sys/mman.h>
31 #include <sys/mount.h>
32 #include <sys/resource.h>
33 #include <sys/socket.h>
34 #include <sys/stat.h>
35 #include <sys/types.h>
36 #include <sys/wait.h>
37 #include <urcu/futex.h>
38 #include <unistd.h>
39 #include <config.h>
40
41 #include <lttng-consumerd.h>
42 #include <lttng-sessiond-comm.h>
43 #include <lttng/lttng-consumer.h>
44
45 #include <lttngerr.h>
46
47 #include "channel.h"
48 #include "compat/poll.h"
49 #include "context.h"
50 #include "event.h"
51 #include "futex.h"
52 #include "hashtable.h"
53 #include "kernel.h"
54 #include "lttng-sessiond.h"
55 #include "shm.h"
56 #include "ust-app.h"
57 #include "ust-ctl.h"
58 #include "utils.h"
59
60 #define CONSUMERD_FILE "lttng-consumerd"
61
62 struct consumer_data {
63 enum lttng_consumer_type type;
64
65 pthread_t thread; /* Worker thread interacting with the consumer */
66 sem_t sem;
67
68 /* Mutex to control consumerd pid assignation */
69 pthread_mutex_t pid_mutex;
70 pid_t pid;
71
72 int err_sock;
73 int cmd_sock;
74
75 /* consumer error and command Unix socket path */
76 char err_unix_sock_path[PATH_MAX];
77 char cmd_unix_sock_path[PATH_MAX];
78 };
79
80 /* Const values */
81 const char default_home_dir[] = DEFAULT_HOME_DIR;
82 const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
83 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
84 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
85
86 /* Variables */
87 int opt_verbose; /* Not static for lttngerr.h */
88 int opt_verbose_consumer; /* Not static for lttngerr.h */
89 int opt_quiet; /* Not static for lttngerr.h */
90
91 const char *progname;
92 const char *opt_tracing_group;
93 static int opt_sig_parent;
94 static int opt_daemon;
95 static int is_root; /* Set to 1 if the daemon is running as root */
96 static pid_t ppid; /* Parent PID for --sig-parent option */
97
98 /* Consumer daemon specific control data */
99 static struct consumer_data kconsumer_data = {
100 .type = LTTNG_CONSUMER_KERNEL,
101 .err_unix_sock_path = KCONSUMERD_ERR_SOCK_PATH,
102 .cmd_unix_sock_path = KCONSUMERD_CMD_SOCK_PATH,
103 };
104 static struct consumer_data ustconsumer64_data = {
105 .type = LTTNG_CONSUMER64_UST,
106 .err_unix_sock_path = USTCONSUMERD64_ERR_SOCK_PATH,
107 .cmd_unix_sock_path = USTCONSUMERD64_CMD_SOCK_PATH,
108 };
109 static struct consumer_data ustconsumer32_data = {
110 .type = LTTNG_CONSUMER32_UST,
111 .err_unix_sock_path = USTCONSUMERD32_ERR_SOCK_PATH,
112 .cmd_unix_sock_path = USTCONSUMERD32_CMD_SOCK_PATH,
113 };
114
115 static int dispatch_thread_exit;
116
117 /* Global application Unix socket path */
118 static char apps_unix_sock_path[PATH_MAX];
119 /* Global client Unix socket path */
120 static char client_unix_sock_path[PATH_MAX];
121 /* global wait shm path for UST */
122 static char wait_shm_path[PATH_MAX];
123
124 /* Sockets and FDs */
125 static int client_sock;
126 static int apps_sock;
127 static int kernel_tracer_fd;
128 static int kernel_poll_pipe[2];
129
130 /*
131 * Quit pipe for all threads. This permits a single cancellation point
132 * for all threads when receiving an event on the pipe.
133 */
134 static int thread_quit_pipe[2];
135
136 /*
137 * This pipe is used to inform the thread managing application communication
138 * that a command is queued and ready to be processed.
139 */
140 static int apps_cmd_pipe[2];
141
142 /* Pthread, Mutexes and Semaphores */
143 static pthread_t apps_thread;
144 static pthread_t reg_apps_thread;
145 static pthread_t client_thread;
146 static pthread_t kernel_thread;
147 static pthread_t dispatch_thread;
148
149
150 /*
151 * UST registration command queue. This queue is tied with a futex and uses a N
152 * wakers / 1 waiter implemented and detailed in futex.c/.h
153 *
154 * The thread_manage_apps and thread_dispatch_ust_registration interact with
155 * this queue and the wait/wake scheme.
156 */
157 static struct ust_cmd_queue ust_cmd_queue;
158
159 /*
160 * Pointer initialized before thread creation.
161 *
162 * This points to the tracing session list containing the session count and a
163 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
164 * MUST NOT be taken if you call a public function in session.c.
165 *
166 * The lock is nested inside the structure: session_list_ptr->lock. Please use
167 * session_lock_list and session_unlock_list for lock acquisition.
168 */
169 static struct ltt_session_list *session_list_ptr;
170
171 int ust_consumerd64_fd = -1;
172 int ust_consumerd32_fd = -1;
173
174 static const char *consumerd32_bin =
175 __stringify(CONFIG_CONSUMERD32_BIN);
176 static const char *consumerd64_bin =
177 __stringify(CONFIG_CONSUMERD64_BIN);
178 static const char *consumerd32_libdir =
179 __stringify(CONFIG_CONSUMERD32_LIBDIR);
180 static const char *consumerd64_libdir =
181 __stringify(CONFIG_CONSUMERD64_LIBDIR);
182
183 static
184 void setup_consumerd_path(void)
185 {
186 const char *bin, *libdir;
187
188 /*
189 * Allow INSTALL_BIN_PATH to be used as a target path for the
190 * native architecture size consumer if CONFIG_CONSUMER*_PATH
191 * has not been defined.
192 */
193 #if (CAA_BITS_PER_LONG == 32)
194 if (!consumerd32_bin[0]) {
195 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
196 }
197 if (!consumerd32_libdir[0]) {
198 consumerd32_libdir = INSTALL_LIB_PATH;
199 }
200 #elif (CAA_BITS_PER_LONG == 64)
201 if (!consumerd64_bin[0]) {
202 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
203 }
204 if (!consumerd64_libdir[0]) {
205 consumerd64_libdir = INSTALL_LIB_PATH;
206 }
207 #else
208 #error "Unknown bitness"
209 #endif
210
211 /*
212 * runtime env. var. overrides the build default.
213 */
214 bin = getenv("LTTNG_CONSUMERD32_BIN");
215 if (bin) {
216 consumerd32_bin = bin;
217 }
218 bin = getenv("LTTNG_CONSUMERD64_BIN");
219 if (bin) {
220 consumerd64_bin = bin;
221 }
222 libdir = getenv("LTTNG_TOOLS_CONSUMERD32_LIBDIR");
223 if (libdir) {
224 consumerd32_libdir = libdir;
225 }
226 libdir = getenv("LTTNG_TOOLS_CONSUMERD64_LIBDIR");
227 if (libdir) {
228 consumerd64_libdir = libdir;
229 }
230 }
231
232 /*
233 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
234 */
235 static int create_thread_poll_set(struct lttng_poll_event *events,
236 unsigned int size)
237 {
238 int ret;
239
240 if (events == NULL || size == 0) {
241 ret = -1;
242 goto error;
243 }
244
245 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
246 if (ret < 0) {
247 goto error;
248 }
249
250 /* Add quit pipe */
251 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
252 if (ret < 0) {
253 goto error;
254 }
255
256 return 0;
257
258 error:
259 return ret;
260 }
261
262 /*
263 * Check if the thread quit pipe was triggered.
264 *
265 * Return 1 if it was triggered else 0;
266 */
267 static int check_thread_quit_pipe(int fd, uint32_t events)
268 {
269 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
270 return 1;
271 }
272
273 return 0;
274 }
275
276 /*
277 * Remove modules in reverse load order.
278 */
279 static int modprobe_remove_kernel_modules(void)
280 {
281 int ret = 0, i;
282 char modprobe[256];
283
284 for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
285 ret = snprintf(modprobe, sizeof(modprobe),
286 "/sbin/modprobe -r -q %s",
287 kernel_modules_list[i].name);
288 if (ret < 0) {
289 perror("snprintf modprobe -r");
290 goto error;
291 }
292 modprobe[sizeof(modprobe) - 1] = '\0';
293 ret = system(modprobe);
294 if (ret == -1) {
295 ERR("Unable to launch modprobe -r for module %s",
296 kernel_modules_list[i].name);
297 } else if (kernel_modules_list[i].required
298 && WEXITSTATUS(ret) != 0) {
299 ERR("Unable to remove module %s",
300 kernel_modules_list[i].name);
301 } else {
302 DBG("Modprobe removal successful %s",
303 kernel_modules_list[i].name);
304 }
305 }
306
307 error:
308 return ret;
309 }
310
311 /*
312 * Return group ID of the tracing group or -1 if not found.
313 */
314 static gid_t allowed_group(void)
315 {
316 struct group *grp;
317
318 if (opt_tracing_group) {
319 grp = getgrnam(opt_tracing_group);
320 } else {
321 grp = getgrnam(default_tracing_group);
322 }
323 if (!grp) {
324 return -1;
325 } else {
326 return grp->gr_gid;
327 }
328 }
329
330 /*
331 * Init thread quit pipe.
332 *
333 * Return -1 on error or 0 if all pipes are created.
334 */
335 static int init_thread_quit_pipe(void)
336 {
337 int ret;
338
339 ret = pipe2(thread_quit_pipe, O_CLOEXEC);
340 if (ret < 0) {
341 perror("thread quit pipe");
342 goto error;
343 }
344
345 error:
346 return ret;
347 }
348
349 /*
350 * Complete teardown of a kernel session. This free all data structure related
351 * to a kernel session and update counter.
352 */
353 static void teardown_kernel_session(struct ltt_session *session)
354 {
355 if (!session->kernel_session) {
356 DBG3("No kernel session when tearingdown session");
357 return;
358 }
359
360 DBG("Tearing down kernel session");
361
362 /*
363 * If a custom kernel consumer was registered, close the socket before
364 * tearing down the complete kernel session structure
365 */
366 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
367 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
368 }
369
370 trace_kernel_destroy_session(session->kernel_session);
371 }
372
373 /*
374 * Complete teardown of all UST sessions. This will free everything on his path
375 * and destroy the core essence of all ust sessions :)
376 */
377 static void teardown_ust_session(struct ltt_session *session)
378 {
379 int ret;
380
381 if (!session->ust_session) {
382 DBG3("No UST session when tearingdown session");
383 return;
384 }
385
386 DBG("Tearing down UST session(s)");
387
388 ret = ust_app_destroy_trace_all(session->ust_session);
389 if (ret) {
390 ERR("Error in ust_app_destroy_trace_all");
391 }
392
393 trace_ust_destroy_session(session->ust_session);
394 }
395
396 /*
397 * Stop all threads by closing the thread quit pipe.
398 */
399 static void stop_threads(void)
400 {
401 int ret;
402
403 /* Stopping all threads */
404 DBG("Terminating all threads");
405 ret = notify_thread_pipe(thread_quit_pipe[1]);
406 if (ret < 0) {
407 ERR("write error on thread quit pipe");
408 }
409
410 /* Dispatch thread */
411 dispatch_thread_exit = 1;
412 futex_nto1_wake(&ust_cmd_queue.futex);
413 }
414
415 /*
416 * Cleanup the daemon
417 */
418 static void cleanup(void)
419 {
420 int ret;
421 char *cmd;
422 struct ltt_session *sess, *stmp;
423
424 DBG("Cleaning up");
425
426 if (is_root) {
427 DBG("Removing %s directory", LTTNG_RUNDIR);
428 ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
429 if (ret < 0) {
430 ERR("asprintf failed. Something is really wrong!");
431 }
432
433 /* Remove lttng run directory */
434 ret = system(cmd);
435 if (ret < 0) {
436 ERR("Unable to clean " LTTNG_RUNDIR);
437 }
438 }
439
440 DBG("Cleaning up all session");
441
442 /* Destroy session list mutex */
443 if (session_list_ptr != NULL) {
444 pthread_mutex_destroy(&session_list_ptr->lock);
445
446 /* Cleanup ALL session */
447 cds_list_for_each_entry_safe(sess, stmp,
448 &session_list_ptr->head, list) {
449 teardown_kernel_session(sess);
450 teardown_ust_session(sess);
451 free(sess);
452 }
453 }
454
455 DBG("Closing all UST sockets");
456 ust_app_clean_list();
457
458 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
459
460 DBG("Closing kernel fd");
461 close(kernel_tracer_fd);
462
463 if (is_root) {
464 DBG("Unloading kernel modules");
465 modprobe_remove_kernel_modules();
466 }
467
468 close(thread_quit_pipe[0]);
469 close(thread_quit_pipe[1]);
470
471 /* <fun> */
472 MSG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
473 "Matthew, BEET driven development works!%c[%dm",
474 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
475 /* </fun> */
476 }
477
478 /*
479 * Send data on a unix socket using the liblttsessiondcomm API.
480 *
481 * Return lttcomm error code.
482 */
483 static int send_unix_sock(int sock, void *buf, size_t len)
484 {
485 /* Check valid length */
486 if (len <= 0) {
487 return -1;
488 }
489
490 return lttcomm_send_unix_sock(sock, buf, len);
491 }
492
493 /*
494 * Free memory of a command context structure.
495 */
496 static void clean_command_ctx(struct command_ctx **cmd_ctx)
497 {
498 DBG("Clean command context structure");
499 if (*cmd_ctx) {
500 if ((*cmd_ctx)->llm) {
501 free((*cmd_ctx)->llm);
502 }
503 if ((*cmd_ctx)->lsm) {
504 free((*cmd_ctx)->lsm);
505 }
506 free(*cmd_ctx);
507 *cmd_ctx = NULL;
508 }
509 }
510
511 /*
512 * Send all stream fds of kernel channel to the consumer.
513 */
514 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
515 int sock, struct ltt_kernel_channel *channel)
516 {
517 int ret;
518 struct ltt_kernel_stream *stream;
519 struct lttcomm_consumer_msg lkm;
520
521 DBG("Sending streams of channel %s to kernel consumer",
522 channel->channel->name);
523
524 /* Send channel */
525 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
526 lkm.u.channel.channel_key = channel->fd;
527 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
528 lkm.u.channel.mmap_len = 0; /* for kernel */
529 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
530 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
531 if (ret < 0) {
532 perror("send consumer channel");
533 goto error;
534 }
535
536 /* Send streams */
537 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
538 if (!stream->fd) {
539 continue;
540 }
541 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
542 lkm.u.stream.channel_key = channel->fd;
543 lkm.u.stream.stream_key = stream->fd;
544 lkm.u.stream.state = stream->state;
545 lkm.u.stream.output = channel->channel->attr.output;
546 lkm.u.stream.mmap_len = 0; /* for kernel */
547 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
548 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
549 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
550 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
551 if (ret < 0) {
552 perror("send consumer stream");
553 goto error;
554 }
555 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
556 if (ret < 0) {
557 perror("send consumer stream ancillary data");
558 goto error;
559 }
560 }
561
562 DBG("consumer channel streams sent");
563
564 return 0;
565
566 error:
567 return ret;
568 }
569
570 /*
571 * Send all stream fds of the kernel session to the consumer.
572 */
573 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
574 struct ltt_kernel_session *session)
575 {
576 int ret;
577 struct ltt_kernel_channel *chan;
578 struct lttcomm_consumer_msg lkm;
579 int sock = session->consumer_fd;
580
581 DBG("Sending metadata stream fd");
582
583 /* Extra protection. It's NOT supposed to be set to 0 at this point */
584 if (session->consumer_fd == 0) {
585 session->consumer_fd = consumer_data->cmd_sock;
586 }
587
588 if (session->metadata_stream_fd != 0) {
589 /* Send metadata channel fd */
590 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
591 lkm.u.channel.channel_key = session->metadata->fd;
592 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
593 lkm.u.channel.mmap_len = 0; /* for kernel */
594 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
595 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
596 if (ret < 0) {
597 perror("send consumer channel");
598 goto error;
599 }
600
601 /* Send metadata stream fd */
602 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
603 lkm.u.stream.channel_key = session->metadata->fd;
604 lkm.u.stream.stream_key = session->metadata_stream_fd;
605 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
606 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
607 lkm.u.stream.mmap_len = 0; /* for kernel */
608 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
609 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
610 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
611 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
612 if (ret < 0) {
613 perror("send consumer stream");
614 goto error;
615 }
616 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
617 if (ret < 0) {
618 perror("send consumer stream");
619 goto error;
620 }
621 }
622
623 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
624 ret = send_kconsumer_channel_streams(consumer_data, sock, chan);
625 if (ret < 0) {
626 goto error;
627 }
628 }
629
630 DBG("consumer fds (metadata and channel streams) sent");
631
632 return 0;
633
634 error:
635 return ret;
636 }
637
638 /*
639 * Notify UST applications using the shm mmap futex.
640 */
641 static int notify_ust_apps(int active)
642 {
643 char *wait_shm_mmap;
644
645 DBG("Notifying applications of session daemon state: %d", active);
646
647 /* See shm.c for this call implying mmap, shm and futex calls */
648 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
649 if (wait_shm_mmap == NULL) {
650 goto error;
651 }
652
653 /* Wake waiting process */
654 futex_wait_update((int32_t *) wait_shm_mmap, active);
655
656 /* Apps notified successfully */
657 return 0;
658
659 error:
660 return -1;
661 }
662
663 /*
664 * Setup the outgoing data buffer for the response (llm) by allocating the
665 * right amount of memory and copying the original information from the lsm
666 * structure.
667 *
668 * Return total size of the buffer pointed by buf.
669 */
670 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
671 {
672 int ret, buf_size;
673
674 buf_size = size;
675
676 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
677 if (cmd_ctx->llm == NULL) {
678 perror("zmalloc");
679 ret = -ENOMEM;
680 goto error;
681 }
682
683 /* Copy common data */
684 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
685 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
686
687 cmd_ctx->llm->data_size = size;
688 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
689
690 return buf_size;
691
692 error:
693 return ret;
694 }
695
696 /*
697 * Update the kernel poll set of all channel fd available over all tracing
698 * session. Add the wakeup pipe at the end of the set.
699 */
700 static int update_kernel_poll(struct lttng_poll_event *events)
701 {
702 int ret;
703 struct ltt_session *session;
704 struct ltt_kernel_channel *channel;
705
706 DBG("Updating kernel poll set");
707
708 session_lock_list();
709 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
710 session_lock(session);
711 if (session->kernel_session == NULL) {
712 session_unlock(session);
713 continue;
714 }
715
716 cds_list_for_each_entry(channel,
717 &session->kernel_session->channel_list.head, list) {
718 /* Add channel fd to the kernel poll set */
719 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
720 if (ret < 0) {
721 session_unlock(session);
722 goto error;
723 }
724 DBG("Channel fd %d added to kernel set", channel->fd);
725 }
726 session_unlock(session);
727 }
728 session_unlock_list();
729
730 return 0;
731
732 error:
733 session_unlock_list();
734 return -1;
735 }
736
737 /*
738 * Find the channel fd from 'fd' over all tracing session. When found, check
739 * for new channel stream and send those stream fds to the kernel consumer.
740 *
741 * Useful for CPU hotplug feature.
742 */
743 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
744 {
745 int ret = 0;
746 struct ltt_session *session;
747 struct ltt_kernel_channel *channel;
748
749 DBG("Updating kernel streams for channel fd %d", fd);
750
751 session_lock_list();
752 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
753 session_lock(session);
754 if (session->kernel_session == NULL) {
755 session_unlock(session);
756 continue;
757 }
758
759 /* This is not suppose to be 0 but this is an extra security check */
760 if (session->kernel_session->consumer_fd == 0) {
761 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
762 }
763
764 cds_list_for_each_entry(channel,
765 &session->kernel_session->channel_list.head, list) {
766 if (channel->fd == fd) {
767 DBG("Channel found, updating kernel streams");
768 ret = kernel_open_channel_stream(channel);
769 if (ret < 0) {
770 goto error;
771 }
772
773 /*
774 * Have we already sent fds to the consumer? If yes, it means
775 * that tracing is started so it is safe to send our updated
776 * stream fds.
777 */
778 if (session->kernel_session->consumer_fds_sent == 1) {
779 ret = send_kconsumer_channel_streams(consumer_data,
780 session->kernel_session->consumer_fd, channel);
781 if (ret < 0) {
782 goto error;
783 }
784 }
785 goto error;
786 }
787 }
788 session_unlock(session);
789 }
790 session_unlock_list();
791 return ret;
792
793 error:
794 session_unlock(session);
795 session_unlock_list();
796 return ret;
797 }
798
799 /*
800 * For each tracing session, update newly registered apps.
801 */
802 static void update_ust_app(int app_sock)
803 {
804 struct ltt_session *sess, *stmp;
805
806 /* For all tracing session(s) */
807 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
808 if (sess->ust_session) {
809 ust_app_global_update(sess->ust_session, app_sock);
810 }
811 }
812 }
813
814 /*
815 * This thread manage event coming from the kernel.
816 *
817 * Features supported in this thread:
818 * -) CPU Hotplug
819 */
820 static void *thread_manage_kernel(void *data)
821 {
822 int ret, i, pollfd, update_poll_flag = 1;
823 uint32_t revents, nb_fd;
824 char tmp;
825 struct lttng_poll_event events;
826
827 DBG("Thread manage kernel started");
828
829 ret = create_thread_poll_set(&events, 2);
830 if (ret < 0) {
831 goto error;
832 }
833
834 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
835 if (ret < 0) {
836 goto error;
837 }
838
839 while (1) {
840 if (update_poll_flag == 1) {
841 /*
842 * Reset number of fd in the poll set. Always 2 since there is the thread
843 * quit pipe and the kernel pipe.
844 */
845 events.nb_fd = 2;
846
847 ret = update_kernel_poll(&events);
848 if (ret < 0) {
849 goto error;
850 }
851 update_poll_flag = 0;
852 }
853
854 nb_fd = LTTNG_POLL_GETNB(&events);
855
856 DBG("Thread kernel polling on %d fds", nb_fd);
857
858 /* Zeroed the poll events */
859 lttng_poll_reset(&events);
860
861 /* Poll infinite value of time */
862 ret = lttng_poll_wait(&events, -1);
863 if (ret < 0) {
864 goto error;
865 } else if (ret == 0) {
866 /* Should not happen since timeout is infinite */
867 ERR("Return value of poll is 0 with an infinite timeout.\n"
868 "This should not have happened! Continuing...");
869 continue;
870 }
871
872 for (i = 0; i < nb_fd; i++) {
873 /* Fetch once the poll data */
874 revents = LTTNG_POLL_GETEV(&events, i);
875 pollfd = LTTNG_POLL_GETFD(&events, i);
876
877 /* Thread quit pipe has been closed. Killing thread. */
878 ret = check_thread_quit_pipe(pollfd, revents);
879 if (ret) {
880 goto error;
881 }
882
883 /* Check for data on kernel pipe */
884 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
885 ret = read(kernel_poll_pipe[0], &tmp, 1);
886 update_poll_flag = 1;
887 continue;
888 } else {
889 /*
890 * New CPU detected by the kernel. Adding kernel stream to
891 * kernel session and updating the kernel consumer
892 */
893 if (revents & LPOLLIN) {
894 ret = update_kernel_stream(&kconsumer_data, pollfd);
895 if (ret < 0) {
896 continue;
897 }
898 break;
899 /*
900 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
901 * and unregister kernel stream at this point.
902 */
903 }
904 }
905 }
906 }
907
908 error:
909 DBG("Kernel thread dying");
910 close(kernel_poll_pipe[0]);
911 close(kernel_poll_pipe[1]);
912
913 lttng_poll_clean(&events);
914
915 return NULL;
916 }
917
918 /*
919 * This thread manage the consumer error sent back to the session daemon.
920 */
921 static void *thread_manage_consumer(void *data)
922 {
923 int sock = 0, i, ret, pollfd;
924 uint32_t revents, nb_fd;
925 enum lttcomm_return_code code;
926 struct lttng_poll_event events;
927 struct consumer_data *consumer_data = data;
928
929 DBG("[thread] Manage consumer started");
930
931 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
932 if (ret < 0) {
933 goto error;
934 }
935
936 /*
937 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
938 * Nothing more will be added to this poll set.
939 */
940 ret = create_thread_poll_set(&events, 2);
941 if (ret < 0) {
942 goto error;
943 }
944
945 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
946 if (ret < 0) {
947 goto error;
948 }
949
950 nb_fd = LTTNG_POLL_GETNB(&events);
951
952 /* Inifinite blocking call, waiting for transmission */
953 ret = lttng_poll_wait(&events, -1);
954 if (ret < 0) {
955 goto error;
956 }
957
958 for (i = 0; i < nb_fd; i++) {
959 /* Fetch once the poll data */
960 revents = LTTNG_POLL_GETEV(&events, i);
961 pollfd = LTTNG_POLL_GETFD(&events, i);
962
963 /* Thread quit pipe has been closed. Killing thread. */
964 ret = check_thread_quit_pipe(pollfd, revents);
965 if (ret) {
966 goto error;
967 }
968
969 /* Event on the registration socket */
970 if (pollfd == consumer_data->err_sock) {
971 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
972 ERR("consumer err socket poll error");
973 goto error;
974 }
975 }
976 }
977
978 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
979 if (sock < 0) {
980 goto error;
981 }
982
983 DBG2("Receiving code from consumer err_sock");
984
985 /* Getting status code from kconsumerd */
986 ret = lttcomm_recv_unix_sock(sock, &code,
987 sizeof(enum lttcomm_return_code));
988 if (ret <= 0) {
989 goto error;
990 }
991
992 if (code == CONSUMERD_COMMAND_SOCK_READY) {
993 consumer_data->cmd_sock =
994 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
995 if (consumer_data->cmd_sock < 0) {
996 sem_post(&consumer_data->sem);
997 PERROR("consumer connect");
998 goto error;
999 }
1000 /* Signal condition to tell that the kconsumerd is ready */
1001 sem_post(&consumer_data->sem);
1002 DBG("consumer command socket ready");
1003 } else {
1004 ERR("consumer error when waiting for SOCK_READY : %s",
1005 lttcomm_get_readable_code(-code));
1006 goto error;
1007 }
1008
1009 /* Remove the kconsumerd error sock since we've established a connexion */
1010 ret = lttng_poll_del(&events, consumer_data->err_sock);
1011 if (ret < 0) {
1012 goto error;
1013 }
1014
1015 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1016 if (ret < 0) {
1017 goto error;
1018 }
1019
1020 /* Update number of fd */
1021 nb_fd = LTTNG_POLL_GETNB(&events);
1022
1023 /* Inifinite blocking call, waiting for transmission */
1024 ret = lttng_poll_wait(&events, -1);
1025 if (ret < 0) {
1026 goto error;
1027 }
1028
1029 for (i = 0; i < nb_fd; i++) {
1030 /* Fetch once the poll data */
1031 revents = LTTNG_POLL_GETEV(&events, i);
1032 pollfd = LTTNG_POLL_GETFD(&events, i);
1033
1034 /* Thread quit pipe has been closed. Killing thread. */
1035 ret = check_thread_quit_pipe(pollfd, revents);
1036 if (ret) {
1037 goto error;
1038 }
1039
1040 /* Event on the kconsumerd socket */
1041 if (pollfd == sock) {
1042 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1043 ERR("consumer err socket second poll error");
1044 goto error;
1045 }
1046 }
1047 }
1048
1049 /* Wait for any kconsumerd error */
1050 ret = lttcomm_recv_unix_sock(sock, &code,
1051 sizeof(enum lttcomm_return_code));
1052 if (ret <= 0) {
1053 ERR("consumer closed the command socket");
1054 goto error;
1055 }
1056
1057 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1058
1059 error:
1060 DBG("consumer thread dying");
1061 close(consumer_data->err_sock);
1062 close(consumer_data->cmd_sock);
1063 close(sock);
1064
1065 unlink(consumer_data->err_unix_sock_path);
1066 unlink(consumer_data->cmd_unix_sock_path);
1067 consumer_data->pid = 0;
1068
1069 lttng_poll_clean(&events);
1070
1071 return NULL;
1072 }
1073
1074 /*
1075 * This thread manage application communication.
1076 */
1077 static void *thread_manage_apps(void *data)
1078 {
1079 int i, ret, pollfd;
1080 uint32_t revents, nb_fd;
1081 struct ust_command ust_cmd;
1082 struct lttng_poll_event events;
1083
1084 DBG("[thread] Manage application started");
1085
1086 rcu_register_thread();
1087 rcu_thread_online();
1088
1089 ret = create_thread_poll_set(&events, 2);
1090 if (ret < 0) {
1091 goto error;
1092 }
1093
1094 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1095 if (ret < 0) {
1096 goto error;
1097 }
1098
1099 while (1) {
1100 /* Zeroed the events structure */
1101 lttng_poll_reset(&events);
1102
1103 nb_fd = LTTNG_POLL_GETNB(&events);
1104
1105 DBG("Apps thread polling on %d fds", nb_fd);
1106
1107 /* Inifinite blocking call, waiting for transmission */
1108 ret = lttng_poll_wait(&events, -1);
1109 if (ret < 0) {
1110 goto error;
1111 }
1112
1113 for (i = 0; i < nb_fd; i++) {
1114 /* Fetch once the poll data */
1115 revents = LTTNG_POLL_GETEV(&events, i);
1116 pollfd = LTTNG_POLL_GETFD(&events, i);
1117
1118 /* Thread quit pipe has been closed. Killing thread. */
1119 ret = check_thread_quit_pipe(pollfd, revents);
1120 if (ret) {
1121 goto error;
1122 }
1123
1124 /* Inspect the apps cmd pipe */
1125 if (pollfd == apps_cmd_pipe[0]) {
1126 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1127 ERR("Apps command pipe error");
1128 goto error;
1129 } else if (revents & LPOLLIN) {
1130 /* Empty pipe */
1131 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1132 if (ret < 0 || ret < sizeof(ust_cmd)) {
1133 perror("read apps cmd pipe");
1134 goto error;
1135 }
1136
1137 /* Register applicaton to the session daemon */
1138 ret = ust_app_register(&ust_cmd.reg_msg,
1139 ust_cmd.sock);
1140 if (ret == -ENOMEM) {
1141 goto error;
1142 } else if (ret < 0) {
1143 break;
1144 }
1145
1146 /*
1147 * Add channel(s) and event(s) to newly registered apps
1148 * from lttng global UST domain.
1149 */
1150 update_ust_app(ust_cmd.sock);
1151
1152 ret = ustctl_register_done(ust_cmd.sock);
1153 if (ret < 0) {
1154 /*
1155 * If the registration is not possible, we simply
1156 * unregister the apps and continue
1157 */
1158 ust_app_unregister(ust_cmd.sock);
1159 } else {
1160 /*
1161 * We just need here to monitor the close of the UST
1162 * socket and poll set monitor those by default.
1163 */
1164 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1165 if (ret < 0) {
1166 goto error;
1167 }
1168
1169 DBG("Apps with sock %d added to poll set",
1170 ust_cmd.sock);
1171 }
1172
1173 break;
1174 }
1175 } else {
1176 /*
1177 * At this point, we know that a registered application made
1178 * the event at poll_wait.
1179 */
1180 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1181 /* Removing from the poll set */
1182 ret = lttng_poll_del(&events, pollfd);
1183 if (ret < 0) {
1184 goto error;
1185 }
1186
1187 /* Socket closed on remote end. */
1188 ust_app_unregister(pollfd);
1189 break;
1190 }
1191 }
1192 }
1193 }
1194
1195 error:
1196 DBG("Application communication apps dying");
1197 close(apps_cmd_pipe[0]);
1198 close(apps_cmd_pipe[1]);
1199
1200 lttng_poll_clean(&events);
1201
1202 rcu_thread_offline();
1203 rcu_unregister_thread();
1204 return NULL;
1205 }
1206
1207 /*
1208 * Dispatch request from the registration threads to the application
1209 * communication thread.
1210 */
1211 static void *thread_dispatch_ust_registration(void *data)
1212 {
1213 int ret;
1214 struct cds_wfq_node *node;
1215 struct ust_command *ust_cmd = NULL;
1216
1217 DBG("[thread] Dispatch UST command started");
1218
1219 while (!dispatch_thread_exit) {
1220 /* Atomically prepare the queue futex */
1221 futex_nto1_prepare(&ust_cmd_queue.futex);
1222
1223 do {
1224 /* Dequeue command for registration */
1225 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1226 if (node == NULL) {
1227 DBG("Woken up but nothing in the UST command queue");
1228 /* Continue thread execution */
1229 break;
1230 }
1231
1232 ust_cmd = caa_container_of(node, struct ust_command, node);
1233
1234 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1235 " gid:%d sock:%d name:%s (version %d.%d)",
1236 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1237 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1238 ust_cmd->sock, ust_cmd->reg_msg.name,
1239 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1240 /*
1241 * Inform apps thread of the new application registration. This
1242 * call is blocking so we can be assured that the data will be read
1243 * at some point in time or wait to the end of the world :)
1244 */
1245 ret = write(apps_cmd_pipe[1], ust_cmd,
1246 sizeof(struct ust_command));
1247 if (ret < 0) {
1248 perror("write apps cmd pipe");
1249 if (errno == EBADF) {
1250 /*
1251 * We can't inform the application thread to process
1252 * registration. We will exit or else application
1253 * registration will not occur and tracing will never
1254 * start.
1255 */
1256 goto error;
1257 }
1258 }
1259 free(ust_cmd);
1260 } while (node != NULL);
1261
1262 /* Futex wait on queue. Blocking call on futex() */
1263 futex_nto1_wait(&ust_cmd_queue.futex);
1264 }
1265
1266 error:
1267 DBG("Dispatch thread dying");
1268 return NULL;
1269 }
1270
1271 /*
1272 * This thread manage application registration.
1273 */
1274 static void *thread_registration_apps(void *data)
1275 {
1276 int sock = 0, i, ret, pollfd;
1277 uint32_t revents, nb_fd;
1278 struct lttng_poll_event events;
1279 /*
1280 * Get allocated in this thread, enqueued to a global queue, dequeued and
1281 * freed in the manage apps thread.
1282 */
1283 struct ust_command *ust_cmd = NULL;
1284
1285 DBG("[thread] Manage application registration started");
1286
1287 ret = lttcomm_listen_unix_sock(apps_sock);
1288 if (ret < 0) {
1289 goto error;
1290 }
1291
1292 /*
1293 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1294 * more will be added to this poll set.
1295 */
1296 ret = create_thread_poll_set(&events, 2);
1297 if (ret < 0) {
1298 goto error;
1299 }
1300
1301 /* Add the application registration socket */
1302 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1303 if (ret < 0) {
1304 goto error;
1305 }
1306
1307 /* Notify all applications to register */
1308 ret = notify_ust_apps(1);
1309 if (ret < 0) {
1310 ERR("Failed to notify applications or create the wait shared memory.\n"
1311 "Execution continues but there might be problem for already\n"
1312 "running applications that wishes to register.");
1313 }
1314
1315 while (1) {
1316 DBG("Accepting application registration");
1317
1318 nb_fd = LTTNG_POLL_GETNB(&events);
1319
1320 /* Inifinite blocking call, waiting for transmission */
1321 ret = lttng_poll_wait(&events, -1);
1322 if (ret < 0) {
1323 goto error;
1324 }
1325
1326 for (i = 0; i < nb_fd; i++) {
1327 /* Fetch once the poll data */
1328 revents = LTTNG_POLL_GETEV(&events, i);
1329 pollfd = LTTNG_POLL_GETFD(&events, i);
1330
1331 /* Thread quit pipe has been closed. Killing thread. */
1332 ret = check_thread_quit_pipe(pollfd, revents);
1333 if (ret) {
1334 goto error;
1335 }
1336
1337 /* Event on the registration socket */
1338 if (pollfd == apps_sock) {
1339 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1340 ERR("Register apps socket poll error");
1341 goto error;
1342 } else if (revents & LPOLLIN) {
1343 sock = lttcomm_accept_unix_sock(apps_sock);
1344 if (sock < 0) {
1345 goto error;
1346 }
1347
1348 /* Create UST registration command for enqueuing */
1349 ust_cmd = zmalloc(sizeof(struct ust_command));
1350 if (ust_cmd == NULL) {
1351 perror("ust command zmalloc");
1352 goto error;
1353 }
1354
1355 /*
1356 * Using message-based transmissions to ensure we don't
1357 * have to deal with partially received messages.
1358 */
1359 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1360 sizeof(struct ust_register_msg));
1361 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1362 if (ret < 0) {
1363 perror("lttcomm_recv_unix_sock register apps");
1364 } else {
1365 ERR("Wrong size received on apps register");
1366 }
1367 free(ust_cmd);
1368 close(sock);
1369 continue;
1370 }
1371
1372 ust_cmd->sock = sock;
1373
1374 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1375 " gid:%d sock:%d name:%s (version %d.%d)",
1376 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1377 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1378 ust_cmd->sock, ust_cmd->reg_msg.name,
1379 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1380
1381 /*
1382 * Lock free enqueue the registration request. The red pill
1383 * has been taken! This apps will be part of the *system*.
1384 */
1385 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1386
1387 /*
1388 * Wake the registration queue futex. Implicit memory
1389 * barrier with the exchange in cds_wfq_enqueue.
1390 */
1391 futex_nto1_wake(&ust_cmd_queue.futex);
1392 }
1393 }
1394 }
1395 }
1396
1397 error:
1398 DBG("UST Registration thread dying");
1399
1400 /* Notify that the registration thread is gone */
1401 notify_ust_apps(0);
1402
1403 close(apps_sock);
1404 close(sock);
1405 unlink(apps_unix_sock_path);
1406
1407 lttng_poll_clean(&events);
1408
1409 return NULL;
1410 }
1411
1412 /*
1413 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1414 * exec or it will fails.
1415 */
1416 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1417 {
1418 int ret;
1419 struct timespec timeout;
1420
1421 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1422 timeout.tv_nsec = 0;
1423
1424 /* Setup semaphore */
1425 ret = sem_init(&consumer_data->sem, 0, 0);
1426 if (ret < 0) {
1427 PERROR("sem_init consumer semaphore");
1428 goto error;
1429 }
1430
1431 ret = pthread_create(&consumer_data->thread, NULL,
1432 thread_manage_consumer, consumer_data);
1433 if (ret != 0) {
1434 PERROR("pthread_create consumer");
1435 ret = -1;
1436 goto error;
1437 }
1438
1439 /* Get time for sem_timedwait absolute timeout */
1440 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1441 if (ret < 0) {
1442 PERROR("clock_gettime spawn consumer");
1443 /* Infinite wait for the kconsumerd thread to be ready */
1444 ret = sem_wait(&consumer_data->sem);
1445 } else {
1446 /* Normal timeout if the gettime was successful */
1447 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1448 ret = sem_timedwait(&consumer_data->sem, &timeout);
1449 }
1450
1451 if (ret < 0) {
1452 if (errno == ETIMEDOUT) {
1453 /*
1454 * Call has timed out so we kill the kconsumerd_thread and return
1455 * an error.
1456 */
1457 ERR("The consumer thread was never ready. Killing it");
1458 ret = pthread_cancel(consumer_data->thread);
1459 if (ret < 0) {
1460 PERROR("pthread_cancel consumer thread");
1461 }
1462 } else {
1463 PERROR("semaphore wait failed consumer thread");
1464 }
1465 goto error;
1466 }
1467
1468 pthread_mutex_lock(&consumer_data->pid_mutex);
1469 if (consumer_data->pid == 0) {
1470 ERR("Kconsumerd did not start");
1471 pthread_mutex_unlock(&consumer_data->pid_mutex);
1472 goto error;
1473 }
1474 pthread_mutex_unlock(&consumer_data->pid_mutex);
1475
1476 return 0;
1477
1478 error:
1479 return ret;
1480 }
1481
1482 /*
1483 * Join consumer thread
1484 */
1485 static int join_consumer_thread(struct consumer_data *consumer_data)
1486 {
1487 void *status;
1488 int ret;
1489
1490 if (consumer_data->pid != 0) {
1491 ret = kill(consumer_data->pid, SIGTERM);
1492 if (ret) {
1493 ERR("Error killing consumer daemon");
1494 return ret;
1495 }
1496 return pthread_join(consumer_data->thread, &status);
1497 } else {
1498 return 0;
1499 }
1500 }
1501
1502 /*
1503 * Fork and exec a consumer daemon (consumerd).
1504 *
1505 * Return pid if successful else -1.
1506 */
1507 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1508 {
1509 int ret;
1510 pid_t pid;
1511 const char *consumer_to_use;
1512 const char *verbosity;
1513 struct stat st;
1514
1515 DBG("Spawning consumerd");
1516
1517 pid = fork();
1518 if (pid == 0) {
1519 /*
1520 * Exec consumerd.
1521 */
1522 if (opt_verbose > 1 || opt_verbose_consumer) {
1523 verbosity = "--verbose";
1524 } else {
1525 verbosity = "--quiet";
1526 }
1527 switch (consumer_data->type) {
1528 case LTTNG_CONSUMER_KERNEL:
1529 /*
1530 * Find out which consumerd to execute. We will first
1531 * try the 64-bit path, then the 32-bit one, then
1532 * fallback on sessiond's installation directory.
1533 */
1534 if (stat(consumerd64_bin, &st) == 0) {
1535 consumer_to_use = consumerd64_bin;
1536 } else if (stat(consumerd32_bin, &st) == 0) {
1537 consumer_to_use = consumerd32_bin;
1538 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1539 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1540 } else {
1541 break;
1542 }
1543 DBG("Using kernel consumer at: %s", consumer_to_use);
1544 execl(consumer_to_use,
1545 "lttng-consumerd", verbosity, "-k",
1546 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1547 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1548 NULL);
1549 break;
1550 case LTTNG_CONSUMER64_UST:
1551 {
1552 char *tmpnew = NULL;
1553
1554 if (consumerd64_libdir[0] != '\0') {
1555 char *tmp;
1556 size_t tmplen;
1557
1558 tmp = getenv("LD_LIBRARY_PATH");
1559 if (!tmp) {
1560 tmp = "";
1561 }
1562 tmplen = strlen("LD_LIBRARY_PATH=")
1563 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1564 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1565 if (!tmpnew) {
1566 ret = -ENOMEM;
1567 goto error;
1568 }
1569 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1570 strcat(tmpnew, consumerd64_libdir);
1571 if (tmp[0] != '\0') {
1572 strcat(tmpnew, ":");
1573 strcat(tmpnew, tmp);
1574 }
1575 ret = putenv(tmpnew);
1576 if (ret) {
1577 ret = -errno;
1578 goto error;
1579 }
1580 }
1581 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1582 ret = execl(consumerd64_bin, verbosity, "-u",
1583 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1584 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1585 NULL);
1586 if (consumerd64_libdir[0] != '\0') {
1587 free(tmpnew);
1588 }
1589 if (ret) {
1590 goto error;
1591 }
1592 break;
1593 }
1594 case LTTNG_CONSUMER32_UST:
1595 {
1596 char *tmpnew = NULL;
1597
1598 if (consumerd32_libdir[0] != '\0') {
1599 char *tmp;
1600 size_t tmplen;
1601
1602 tmp = getenv("LD_LIBRARY_PATH");
1603 if (!tmp) {
1604 tmp = "";
1605 }
1606 tmplen = strlen("LD_LIBRARY_PATH=")
1607 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1608 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1609 if (!tmpnew) {
1610 ret = -ENOMEM;
1611 goto error;
1612 }
1613 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1614 strcat(tmpnew, consumerd32_libdir);
1615 if (tmp[0] != '\0') {
1616 strcat(tmpnew, ":");
1617 strcat(tmpnew, tmp);
1618 }
1619 ret = putenv(tmpnew);
1620 if (ret) {
1621 ret = -errno;
1622 goto error;
1623 }
1624 }
1625 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1626 ret = execl(consumerd32_bin, verbosity, "-u",
1627 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1628 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1629 NULL);
1630 if (consumerd32_libdir[0] != '\0') {
1631 free(tmpnew);
1632 }
1633 if (ret) {
1634 goto error;
1635 }
1636 break;
1637 }
1638 default:
1639 perror("unknown consumer type");
1640 exit(EXIT_FAILURE);
1641 }
1642 if (errno != 0) {
1643 perror("kernel start consumer exec");
1644 }
1645 exit(EXIT_FAILURE);
1646 } else if (pid > 0) {
1647 ret = pid;
1648 } else {
1649 perror("start consumer fork");
1650 ret = -errno;
1651 }
1652 error:
1653 return ret;
1654 }
1655
1656 /*
1657 * Spawn the consumerd daemon and session daemon thread.
1658 */
1659 static int start_consumerd(struct consumer_data *consumer_data)
1660 {
1661 int ret;
1662
1663 pthread_mutex_lock(&consumer_data->pid_mutex);
1664 if (consumer_data->pid != 0) {
1665 pthread_mutex_unlock(&consumer_data->pid_mutex);
1666 goto end;
1667 }
1668
1669 ret = spawn_consumerd(consumer_data);
1670 if (ret < 0) {
1671 ERR("Spawning consumerd failed");
1672 pthread_mutex_unlock(&consumer_data->pid_mutex);
1673 goto error;
1674 }
1675
1676 /* Setting up the consumer_data pid */
1677 consumer_data->pid = ret;
1678 DBG2("Consumer pid %d", consumer_data->pid);
1679 pthread_mutex_unlock(&consumer_data->pid_mutex);
1680
1681 DBG2("Spawning consumer control thread");
1682 ret = spawn_consumer_thread(consumer_data);
1683 if (ret < 0) {
1684 ERR("Fatal error spawning consumer control thread");
1685 goto error;
1686 }
1687
1688 end:
1689 return 0;
1690
1691 error:
1692 return ret;
1693 }
1694
1695 /*
1696 * modprobe_kernel_modules
1697 */
1698 static int modprobe_kernel_modules(void)
1699 {
1700 int ret = 0, i;
1701 char modprobe[256];
1702
1703 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1704 ret = snprintf(modprobe, sizeof(modprobe),
1705 "/sbin/modprobe %s%s",
1706 kernel_modules_list[i].required ? "" : "-q ",
1707 kernel_modules_list[i].name);
1708 if (ret < 0) {
1709 perror("snprintf modprobe");
1710 goto error;
1711 }
1712 modprobe[sizeof(modprobe) - 1] = '\0';
1713 ret = system(modprobe);
1714 if (ret == -1) {
1715 ERR("Unable to launch modprobe for module %s",
1716 kernel_modules_list[i].name);
1717 } else if (kernel_modules_list[i].required
1718 && WEXITSTATUS(ret) != 0) {
1719 ERR("Unable to load module %s",
1720 kernel_modules_list[i].name);
1721 } else {
1722 DBG("Modprobe successfully %s",
1723 kernel_modules_list[i].name);
1724 }
1725 }
1726
1727 error:
1728 return ret;
1729 }
1730
1731 /*
1732 * mount_debugfs
1733 */
1734 static int mount_debugfs(char *path)
1735 {
1736 int ret;
1737 char *type = "debugfs";
1738
1739 ret = mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1740 if (ret < 0) {
1741 PERROR("Cannot create debugfs path");
1742 goto error;
1743 }
1744
1745 ret = mount(type, path, type, 0, NULL);
1746 if (ret < 0) {
1747 PERROR("Cannot mount debugfs");
1748 goto error;
1749 }
1750
1751 DBG("Mounted debugfs successfully at %s", path);
1752
1753 error:
1754 return ret;
1755 }
1756
1757 /*
1758 * Setup necessary data for kernel tracer action.
1759 */
1760 static void init_kernel_tracer(void)
1761 {
1762 int ret;
1763 char *proc_mounts = "/proc/mounts";
1764 char line[256];
1765 char *debugfs_path = NULL, *lttng_path = NULL;
1766 FILE *fp;
1767
1768 /* Detect debugfs */
1769 fp = fopen(proc_mounts, "r");
1770 if (fp == NULL) {
1771 ERR("Unable to probe %s", proc_mounts);
1772 goto error;
1773 }
1774
1775 while (fgets(line, sizeof(line), fp) != NULL) {
1776 if (strstr(line, "debugfs") != NULL) {
1777 /* Remove first string */
1778 strtok(line, " ");
1779 /* Dup string here so we can reuse line later on */
1780 debugfs_path = strdup(strtok(NULL, " "));
1781 DBG("Got debugfs path : %s", debugfs_path);
1782 break;
1783 }
1784 }
1785
1786 fclose(fp);
1787
1788 /* Mount debugfs if needded */
1789 if (debugfs_path == NULL) {
1790 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1791 if (ret < 0) {
1792 perror("asprintf debugfs path");
1793 goto error;
1794 }
1795 ret = mount_debugfs(debugfs_path);
1796 if (ret < 0) {
1797 perror("Cannot mount debugfs");
1798 goto error;
1799 }
1800 }
1801
1802 /* Modprobe lttng kernel modules */
1803 ret = modprobe_kernel_modules();
1804 if (ret < 0) {
1805 goto error;
1806 }
1807
1808 /* Setup lttng kernel path */
1809 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1810 if (ret < 0) {
1811 perror("asprintf lttng path");
1812 goto error;
1813 }
1814
1815 /* Open debugfs lttng */
1816 kernel_tracer_fd = open(lttng_path, O_RDWR);
1817 if (kernel_tracer_fd < 0) {
1818 DBG("Failed to open %s", lttng_path);
1819 goto error;
1820 }
1821
1822 free(lttng_path);
1823 free(debugfs_path);
1824 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1825 return;
1826
1827 error:
1828 if (lttng_path) {
1829 free(lttng_path);
1830 }
1831 if (debugfs_path) {
1832 free(debugfs_path);
1833 }
1834 WARN("No kernel tracer available");
1835 kernel_tracer_fd = 0;
1836 return;
1837 }
1838
1839 /*
1840 * Init tracing by creating trace directory and sending fds kernel consumer.
1841 */
1842 static int init_kernel_tracing(struct ltt_kernel_session *session)
1843 {
1844 int ret = 0;
1845
1846 if (session->consumer_fds_sent == 0) {
1847 /*
1848 * Assign default kernel consumer socket if no consumer assigned to the
1849 * kernel session. At this point, it's NOT suppose to be 0 but this is
1850 * an extra security check.
1851 */
1852 if (session->consumer_fd == 0) {
1853 session->consumer_fd = kconsumer_data.cmd_sock;
1854 }
1855
1856 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1857 if (ret < 0) {
1858 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1859 goto error;
1860 }
1861
1862 session->consumer_fds_sent = 1;
1863 }
1864
1865 error:
1866 return ret;
1867 }
1868
1869 /*
1870 * Create an UST session and add it to the session ust list.
1871 */
1872 static int create_ust_session(struct ltt_session *session,
1873 struct lttng_domain *domain)
1874 {
1875 int ret;
1876 unsigned int uid;
1877 struct ltt_ust_session *lus = NULL;
1878
1879 switch (domain->type) {
1880 case LTTNG_DOMAIN_UST:
1881 break;
1882 default:
1883 ret = LTTCOMM_UNKNOWN_DOMAIN;
1884 goto error;
1885 }
1886
1887 DBG("Creating UST session");
1888
1889 uid = session->uid;
1890 lus = trace_ust_create_session(session->path, uid, domain);
1891 if (lus == NULL) {
1892 ret = LTTCOMM_UST_SESS_FAIL;
1893 goto error;
1894 }
1895
1896 ret = mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1897 geteuid(), allowed_group());
1898 if (ret < 0) {
1899 if (ret != -EEXIST) {
1900 ERR("Trace directory creation error");
1901 ret = LTTCOMM_UST_SESS_FAIL;
1902 goto error;
1903 }
1904 }
1905
1906 /* The domain type dictate different actions on session creation */
1907 switch (domain->type) {
1908 case LTTNG_DOMAIN_UST:
1909 /* No ustctl for the global UST domain */
1910 break;
1911 default:
1912 ERR("Unknown UST domain on create session %d", domain->type);
1913 goto error;
1914 }
1915 session->ust_session = lus;
1916
1917 return LTTCOMM_OK;
1918
1919 error:
1920 free(lus);
1921 return ret;
1922 }
1923
1924 /*
1925 * Create a kernel tracer session then create the default channel.
1926 */
1927 static int create_kernel_session(struct ltt_session *session)
1928 {
1929 int ret;
1930
1931 DBG("Creating kernel session");
1932
1933 ret = kernel_create_session(session, kernel_tracer_fd);
1934 if (ret < 0) {
1935 ret = LTTCOMM_KERN_SESS_FAIL;
1936 goto error;
1937 }
1938
1939 /* Set kernel consumer socket fd */
1940 if (kconsumer_data.cmd_sock) {
1941 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1942 }
1943
1944 ret = mkdir_recursive(session->kernel_session->trace_path,
1945 S_IRWXU | S_IRWXG, geteuid(), allowed_group());
1946 if (ret < 0) {
1947 if (ret != -EEXIST) {
1948 ERR("Trace directory creation error");
1949 goto error;
1950 }
1951 }
1952
1953 error:
1954 return ret;
1955 }
1956
1957 /*
1958 * Using the session list, filled a lttng_session array to send back to the
1959 * client for session listing.
1960 *
1961 * The session list lock MUST be acquired before calling this function. Use
1962 * session_lock_list() and session_unlock_list().
1963 */
1964 static void list_lttng_sessions(struct lttng_session *sessions)
1965 {
1966 int i = 0;
1967 struct ltt_session *session;
1968
1969 DBG("Getting all available session");
1970 /*
1971 * Iterate over session list and append data after the control struct in
1972 * the buffer.
1973 */
1974 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1975 strncpy(sessions[i].path, session->path, PATH_MAX);
1976 sessions[i].path[PATH_MAX - 1] = '\0';
1977 strncpy(sessions[i].name, session->name, NAME_MAX);
1978 sessions[i].name[NAME_MAX - 1] = '\0';
1979 sessions[i].enabled = session->enabled;
1980 i++;
1981 }
1982 }
1983
1984 /*
1985 * Fill lttng_channel array of all channels.
1986 */
1987 static void list_lttng_channels(int domain, struct ltt_session *session,
1988 struct lttng_channel *channels)
1989 {
1990 int i = 0;
1991 struct ltt_kernel_channel *kchan;
1992
1993 DBG("Listing channels for session %s", session->name);
1994
1995 switch (domain) {
1996 case LTTNG_DOMAIN_KERNEL:
1997 /* Kernel channels */
1998 if (session->kernel_session != NULL) {
1999 cds_list_for_each_entry(kchan,
2000 &session->kernel_session->channel_list.head, list) {
2001 /* Copy lttng_channel struct to array */
2002 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2003 channels[i].enabled = kchan->enabled;
2004 i++;
2005 }
2006 }
2007 break;
2008 case LTTNG_DOMAIN_UST:
2009 {
2010 struct cds_lfht_iter iter;
2011 struct ltt_ust_channel *uchan;
2012
2013 cds_lfht_for_each_entry(session->ust_session->domain_global.channels,
2014 &iter, uchan, node) {
2015 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2016 channels[i].attr.overwrite = uchan->attr.overwrite;
2017 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2018 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2019 channels[i].attr.switch_timer_interval =
2020 uchan->attr.switch_timer_interval;
2021 channels[i].attr.read_timer_interval =
2022 uchan->attr.read_timer_interval;
2023 channels[i].enabled = uchan->enabled;
2024 switch (uchan->attr.output) {
2025 case LTTNG_UST_MMAP:
2026 default:
2027 channels[i].attr.output = LTTNG_EVENT_MMAP;
2028 break;
2029 }
2030 i++;
2031 }
2032 break;
2033 }
2034 default:
2035 break;
2036 }
2037 }
2038
2039 /*
2040 * Create a list of ust global domain events.
2041 */
2042 static int list_lttng_ust_global_events(char *channel_name,
2043 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2044 {
2045 int i = 0, ret = 0;
2046 unsigned int nb_event = 0;
2047 struct cds_lfht_iter iter;
2048 struct cds_lfht_node *node;
2049 struct ltt_ust_channel *uchan;
2050 struct ltt_ust_event *uevent;
2051 struct lttng_event *tmp;
2052
2053 DBG("Listing UST global events for channel %s", channel_name);
2054
2055 rcu_read_lock();
2056
2057 node = hashtable_lookup(ust_global->channels, (void *) channel_name,
2058 strlen(channel_name), &iter);
2059 if (node == NULL) {
2060 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2061 goto error;
2062 }
2063
2064 uchan = caa_container_of(node, struct ltt_ust_channel, node);
2065
2066 nb_event += hashtable_get_count(uchan->events);
2067
2068 if (nb_event == 0) {
2069 ret = nb_event;
2070 goto error;
2071 }
2072
2073 DBG3("Listing UST global %d events", nb_event);
2074
2075 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2076 if (tmp == NULL) {
2077 ret = -LTTCOMM_FATAL;
2078 goto error;
2079 }
2080
2081 cds_lfht_for_each_entry(uchan->events, &iter, uevent, node) {
2082 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2083 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2084 tmp[i].enabled = uevent->enabled;
2085 switch (uevent->attr.instrumentation) {
2086 case LTTNG_UST_TRACEPOINT:
2087 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2088 break;
2089 case LTTNG_UST_PROBE:
2090 tmp[i].type = LTTNG_EVENT_PROBE;
2091 break;
2092 case LTTNG_UST_FUNCTION:
2093 tmp[i].type = LTTNG_EVENT_FUNCTION;
2094 break;
2095 case LTTNG_UST_TRACEPOINT_LOGLEVEL:
2096 /* TODO */
2097 ret = -LTTCOMM_NOT_IMPLEMENTED;
2098 goto error;
2099 break;
2100 }
2101 i++;
2102 }
2103
2104 ret = nb_event;
2105 *events = tmp;
2106
2107 error:
2108 rcu_read_unlock();
2109 return ret;
2110 }
2111
2112 /*
2113 * Fill lttng_event array of all kernel events in the channel.
2114 */
2115 static int list_lttng_kernel_events(char *channel_name,
2116 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2117 {
2118 int i = 0, ret;
2119 unsigned int nb_event;
2120 struct ltt_kernel_event *event;
2121 struct ltt_kernel_channel *kchan;
2122
2123 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2124 if (kchan == NULL) {
2125 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2126 goto error;
2127 }
2128
2129 nb_event = kchan->event_count;
2130
2131 DBG("Listing events for channel %s", kchan->channel->name);
2132
2133 if (nb_event == 0) {
2134 ret = nb_event;
2135 goto error;
2136 }
2137
2138 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2139 if (*events == NULL) {
2140 ret = LTTCOMM_FATAL;
2141 goto error;
2142 }
2143
2144 /* Kernel channels */
2145 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2146 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2147 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2148 (*events)[i].enabled = event->enabled;
2149 switch (event->event->instrumentation) {
2150 case LTTNG_KERNEL_TRACEPOINT:
2151 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2152 break;
2153 case LTTNG_KERNEL_KPROBE:
2154 case LTTNG_KERNEL_KRETPROBE:
2155 (*events)[i].type = LTTNG_EVENT_PROBE;
2156 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2157 sizeof(struct lttng_kernel_kprobe));
2158 break;
2159 case LTTNG_KERNEL_FUNCTION:
2160 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2161 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2162 sizeof(struct lttng_kernel_function));
2163 break;
2164 case LTTNG_KERNEL_NOOP:
2165 (*events)[i].type = LTTNG_EVENT_NOOP;
2166 break;
2167 case LTTNG_KERNEL_SYSCALL:
2168 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2169 break;
2170 case LTTNG_KERNEL_ALL:
2171 assert(0);
2172 break;
2173 }
2174 i++;
2175 }
2176
2177 return nb_event;
2178
2179 error:
2180 return ret;
2181 }
2182
2183 /*
2184 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2185 */
2186 static int cmd_disable_channel(struct ltt_session *session,
2187 int domain, char *channel_name)
2188 {
2189 int ret;
2190 struct ltt_ust_session *usess;
2191
2192 usess = session->ust_session;
2193
2194 switch (domain) {
2195 case LTTNG_DOMAIN_KERNEL:
2196 {
2197 ret = channel_kernel_disable(session->kernel_session,
2198 channel_name);
2199 if (ret != LTTCOMM_OK) {
2200 goto error;
2201 }
2202
2203 kernel_wait_quiescent(kernel_tracer_fd);
2204 break;
2205 }
2206 case LTTNG_DOMAIN_UST:
2207 {
2208 struct ltt_ust_channel *uchan;
2209
2210 /* Get channel in global UST domain HT */
2211 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2212 channel_name);
2213 if (uchan == NULL) {
2214 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2215 goto error;
2216 }
2217
2218 /* Already disabled */
2219 if (!uchan->enabled) {
2220 DBG2("UST channel %s already disabled", channel_name);
2221 break;
2222 }
2223
2224 ret = ust_app_disable_channel_glb(usess, uchan);
2225 if (ret < 0) {
2226 ret = LTTCOMM_UST_DISABLE_FAIL;
2227 goto error;
2228 }
2229
2230 uchan->enabled = 0;
2231
2232 break;
2233 }
2234 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2235 case LTTNG_DOMAIN_UST_EXEC_NAME:
2236 case LTTNG_DOMAIN_UST_PID:
2237 ret = LTTCOMM_NOT_IMPLEMENTED;
2238 goto error;
2239 default:
2240 ret = LTTCOMM_UNKNOWN_DOMAIN;
2241 goto error;
2242 }
2243
2244 ret = LTTCOMM_OK;
2245
2246 error:
2247 return ret;
2248 }
2249
2250 /*
2251 * Copy channel from attributes and set it in the application channel list.
2252 */
2253 /*
2254 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
2255 struct lttng_channel *attr, struct ust_app *app)
2256 {
2257 int ret;
2258 struct ltt_ust_channel *uchan, *new_chan;
2259
2260 uchan = trace_ust_get_channel_by_key(usess->channels, attr->name);
2261 if (uchan == NULL) {
2262 ret = LTTCOMM_FATAL;
2263 goto error;
2264 }
2265
2266 new_chan = trace_ust_create_channel(attr, usess->path);
2267 if (new_chan == NULL) {
2268 PERROR("malloc ltt_ust_channel");
2269 ret = LTTCOMM_FATAL;
2270 goto error;
2271 }
2272
2273 ret = channel_ust_copy(new_chan, uchan);
2274 if (ret < 0) {
2275 ret = LTTCOMM_FATAL;
2276 goto error;
2277 }
2278
2279 error:
2280 return ret;
2281 }
2282 */
2283
2284 /*
2285 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2286 */
2287 static int cmd_enable_channel(struct ltt_session *session,
2288 int domain, struct lttng_channel *attr)
2289 {
2290 int ret;
2291 struct ltt_ust_session *usess = session->ust_session;
2292
2293 DBG("Enabling channel %s for session %s", attr->name, session->name);
2294
2295 switch (domain) {
2296 case LTTNG_DOMAIN_KERNEL:
2297 {
2298 struct ltt_kernel_channel *kchan;
2299
2300 kchan = trace_kernel_get_channel_by_name(attr->name,
2301 session->kernel_session);
2302 if (kchan == NULL) {
2303 ret = channel_kernel_create(session->kernel_session,
2304 attr, kernel_poll_pipe[1]);
2305 } else {
2306 ret = channel_kernel_enable(session->kernel_session, kchan);
2307 }
2308
2309 if (ret != LTTCOMM_OK) {
2310 goto error;
2311 }
2312
2313 kernel_wait_quiescent(kernel_tracer_fd);
2314 break;
2315 }
2316 case LTTNG_DOMAIN_UST:
2317 {
2318 struct ltt_ust_channel *uchan;
2319
2320 DBG2("Enabling channel for LTTNG_DOMAIN_UST");
2321
2322 /* Get channel in global UST domain HT */
2323 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2324 attr->name);
2325 if (uchan == NULL) {
2326 uchan = trace_ust_create_channel(attr, usess->pathname);
2327 if (uchan == NULL) {
2328 ret = LTTCOMM_UST_CHAN_FAIL;
2329 goto error;
2330 }
2331
2332 /* Add channel to all registered applications */
2333 ret = ust_app_create_channel_glb(usess, uchan);
2334 if (ret != 0) {
2335 ret = LTTCOMM_UST_CHAN_FAIL;
2336 goto error;
2337 }
2338
2339 rcu_read_lock();
2340 hashtable_add_unique(usess->domain_global.channels, &uchan->node);
2341 rcu_read_unlock();
2342
2343 DBG2("UST channel %s added to global domain HT", attr->name);
2344 } else {
2345 /* If already enabled, everything is OK */
2346 if (uchan->enabled) {
2347 break;
2348 }
2349
2350 ret = ust_app_enable_channel_glb(usess, uchan);
2351 if (ret < 0) {
2352 if (ret != -EEXIST) {
2353 ret = LTTCOMM_UST_CHAN_ENABLE_FAIL;
2354 goto error;
2355 } else {
2356 ret = LTTCOMM_OK;
2357 }
2358 }
2359 }
2360
2361 uchan->enabled = 1;
2362
2363 break;
2364 }
2365 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2366 case LTTNG_DOMAIN_UST_EXEC_NAME:
2367 case LTTNG_DOMAIN_UST_PID:
2368 ret = LTTCOMM_NOT_IMPLEMENTED;
2369 goto error;
2370 default:
2371 ret = LTTCOMM_UNKNOWN_DOMAIN;
2372 goto error;
2373 }
2374
2375 ret = LTTCOMM_OK;
2376
2377 error:
2378 return ret;
2379 }
2380
2381 /*
2382 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2383 */
2384 static int cmd_disable_event(struct ltt_session *session, int domain,
2385 char *channel_name, char *event_name)
2386 {
2387 int ret;
2388
2389 switch (domain) {
2390 case LTTNG_DOMAIN_KERNEL:
2391 {
2392 struct ltt_kernel_channel *kchan;
2393 struct ltt_kernel_session *ksess;
2394
2395 ksess = session->kernel_session;
2396
2397 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2398 if (kchan == NULL) {
2399 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2400 goto error;
2401 }
2402
2403 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2404 if (ret != LTTCOMM_OK) {
2405 goto error;
2406 }
2407
2408 kernel_wait_quiescent(kernel_tracer_fd);
2409 break;
2410 }
2411 case LTTNG_DOMAIN_UST:
2412 {
2413 struct ltt_ust_session *usess;
2414 struct ltt_ust_channel *uchan;
2415 struct ltt_ust_event *uevent;
2416
2417 usess = session->ust_session;
2418
2419 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2420 channel_name);
2421 if (uchan == NULL) {
2422 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2423 goto error;
2424 }
2425
2426 uevent = trace_ust_find_event_by_name(uchan->events, event_name);
2427 if (uevent == NULL) {
2428 ret = LTTCOMM_UST_EVENT_NOT_FOUND;
2429 goto error;
2430 }
2431
2432 ret = ust_app_disable_event_glb(usess, uchan, uevent);
2433 if (ret < 0) {
2434 ret = LTTCOMM_UST_DISABLE_FAIL;
2435 goto error;
2436 }
2437
2438 uevent->enabled = 0;
2439
2440 DBG2("Disable UST event %s in channel %s completed", event_name,
2441 channel_name);
2442
2443 break;
2444 }
2445 case LTTNG_DOMAIN_UST_EXEC_NAME:
2446 case LTTNG_DOMAIN_UST_PID:
2447 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2448 default:
2449 ret = LTTCOMM_NOT_IMPLEMENTED;
2450 goto error;
2451 }
2452
2453 ret = LTTCOMM_OK;
2454
2455 error:
2456 return ret;
2457 }
2458
2459 /*
2460 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2461 */
2462 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2463 char *channel_name)
2464 {
2465 int ret;
2466
2467 switch (domain) {
2468 case LTTNG_DOMAIN_KERNEL:
2469 {
2470 struct ltt_kernel_session *ksess;
2471 struct ltt_kernel_channel *kchan;
2472
2473 ksess = session->kernel_session;
2474
2475 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2476 if (kchan == NULL) {
2477 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2478 goto error;
2479 }
2480
2481 ret = event_kernel_disable_all(ksess, kchan);
2482 if (ret != LTTCOMM_OK) {
2483 goto error;
2484 }
2485
2486 kernel_wait_quiescent(kernel_tracer_fd);
2487 break;
2488 }
2489 case LTTNG_DOMAIN_UST:
2490 {
2491 struct ltt_ust_session *usess;
2492 struct ltt_ust_channel *uchan;
2493
2494 usess = session->ust_session;
2495
2496 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2497 channel_name);
2498 if (uchan == NULL) {
2499 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2500 goto error;
2501 }
2502
2503 ret = ust_app_disable_all_event_glb(usess, uchan);
2504 if (ret < 0) {
2505 ret = LTTCOMM_UST_DISABLE_FAIL;
2506 goto error;
2507 }
2508
2509 DBG2("Disable all UST event in channel %s completed", channel_name);
2510
2511 break;
2512 }
2513 case LTTNG_DOMAIN_UST_EXEC_NAME:
2514 case LTTNG_DOMAIN_UST_PID:
2515 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2516 default:
2517 ret = LTTCOMM_NOT_IMPLEMENTED;
2518 goto error;
2519 }
2520
2521 ret = LTTCOMM_OK;
2522
2523 error:
2524 return ret;
2525 }
2526
2527 /*
2528 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2529 */
2530 static int cmd_add_context(struct ltt_session *session, int domain,
2531 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2532 {
2533 int ret;
2534
2535 switch (domain) {
2536 case LTTNG_DOMAIN_KERNEL:
2537 /* Add kernel context to kernel tracer */
2538 ret = context_kernel_add(session->kernel_session, ctx,
2539 event_name, channel_name);
2540 if (ret != LTTCOMM_OK) {
2541 goto error;
2542 }
2543 break;
2544 case LTTNG_DOMAIN_UST:
2545 {
2546 struct ltt_ust_session *usess = session->ust_session;
2547
2548 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2549 if (ret != LTTCOMM_OK) {
2550 goto error;
2551 }
2552 break;
2553 }
2554 case LTTNG_DOMAIN_UST_EXEC_NAME:
2555 case LTTNG_DOMAIN_UST_PID:
2556 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2557 default:
2558 ret = LTTCOMM_NOT_IMPLEMENTED;
2559 goto error;
2560 }
2561
2562 ret = LTTCOMM_OK;
2563
2564 error:
2565 return ret;
2566 }
2567
2568 /*
2569 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2570 *
2571 * TODO: currently, both events and loglevels are kept within the same
2572 * namespace for UST global registry/app registery, so if an event
2573 * happen to have the same name as the loglevel (very unlikely though),
2574 * and an attempt is made to enable/disable both in the same session,
2575 * the first to be created will be the only one allowed to exist.
2576 */
2577 static int cmd_enable_event(struct ltt_session *session, int domain,
2578 char *channel_name, struct lttng_event *event)
2579 {
2580 int ret;
2581 struct lttng_channel *attr;
2582 struct ltt_ust_session *usess = session->ust_session;
2583
2584 switch (domain) {
2585 case LTTNG_DOMAIN_KERNEL:
2586 {
2587 struct ltt_kernel_channel *kchan;
2588
2589 kchan = trace_kernel_get_channel_by_name(channel_name,
2590 session->kernel_session);
2591 if (kchan == NULL) {
2592 attr = channel_new_default_attr(domain);
2593 if (attr == NULL) {
2594 ret = LTTCOMM_FATAL;
2595 goto error;
2596 }
2597 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2598
2599 /* This call will notify the kernel thread */
2600 ret = channel_kernel_create(session->kernel_session,
2601 attr, kernel_poll_pipe[1]);
2602 if (ret != LTTCOMM_OK) {
2603 free(attr);
2604 goto error;
2605 }
2606 free(attr);
2607 }
2608
2609 /* Get the newly created kernel channel pointer */
2610 kchan = trace_kernel_get_channel_by_name(channel_name,
2611 session->kernel_session);
2612 if (kchan == NULL) {
2613 /* This sould not happen... */
2614 ret = LTTCOMM_FATAL;
2615 goto error;
2616 }
2617
2618 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2619 event);
2620 if (ret != LTTCOMM_OK) {
2621 goto error;
2622 }
2623
2624 kernel_wait_quiescent(kernel_tracer_fd);
2625 break;
2626 }
2627 case LTTNG_DOMAIN_UST:
2628 {
2629 struct lttng_channel *attr;
2630 struct ltt_ust_channel *uchan;
2631
2632 /* Get channel from global UST domain */
2633 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2634 channel_name);
2635 if (uchan == NULL) {
2636 /* Create default channel */
2637 attr = channel_new_default_attr(domain);
2638 if (attr == NULL) {
2639 ret = LTTCOMM_FATAL;
2640 goto error;
2641 }
2642 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2643 attr->name[NAME_MAX - 1] = '\0';
2644
2645 /* Use the internal command enable channel */
2646 ret = cmd_enable_channel(session, domain, attr);
2647 if (ret != LTTCOMM_OK) {
2648 free(attr);
2649 goto error;
2650 }
2651 free(attr);
2652
2653 /* Get the newly created channel reference back */
2654 uchan = trace_ust_find_channel_by_name(
2655 usess->domain_global.channels, channel_name);
2656 if (uchan == NULL) {
2657 /* Something is really wrong */
2658 ret = LTTCOMM_FATAL;
2659 goto error;
2660 }
2661 }
2662
2663 /* At this point, the session and channel exist on the tracer */
2664
2665 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2666 if (ret != LTTCOMM_OK) {
2667 goto error;
2668 }
2669 break;
2670 }
2671 case LTTNG_DOMAIN_UST_EXEC_NAME:
2672 case LTTNG_DOMAIN_UST_PID:
2673 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2674 default:
2675 ret = LTTCOMM_NOT_IMPLEMENTED;
2676 goto error;
2677 }
2678
2679 ret = LTTCOMM_OK;
2680
2681 error:
2682 return ret;
2683 }
2684
2685 /*
2686 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2687 */
2688 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2689 char *channel_name, int event_type)
2690 {
2691 int ret;
2692 struct ltt_kernel_channel *kchan;
2693
2694 switch (domain) {
2695 case LTTNG_DOMAIN_KERNEL:
2696 kchan = trace_kernel_get_channel_by_name(channel_name,
2697 session->kernel_session);
2698 if (kchan == NULL) {
2699 /* This call will notify the kernel thread */
2700 ret = channel_kernel_create(session->kernel_session, NULL,
2701 kernel_poll_pipe[1]);
2702 if (ret != LTTCOMM_OK) {
2703 goto error;
2704 }
2705
2706 /* Get the newly created kernel channel pointer */
2707 kchan = trace_kernel_get_channel_by_name(channel_name,
2708 session->kernel_session);
2709 if (kchan == NULL) {
2710 /* This sould not happen... */
2711 ret = LTTCOMM_FATAL;
2712 goto error;
2713 }
2714
2715 }
2716
2717 switch (event_type) {
2718 case LTTNG_EVENT_SYSCALL:
2719 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2720 kchan, kernel_tracer_fd);
2721 break;
2722 case LTTNG_EVENT_TRACEPOINT:
2723 /*
2724 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2725 * events already registered to the channel.
2726 */
2727 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2728 kchan, kernel_tracer_fd);
2729 break;
2730 case LTTNG_EVENT_ALL:
2731 /* Enable syscalls and tracepoints */
2732 ret = event_kernel_enable_all(session->kernel_session,
2733 kchan, kernel_tracer_fd);
2734 break;
2735 default:
2736 ret = LTTCOMM_KERN_ENABLE_FAIL;
2737 goto error;
2738 }
2739
2740 /* Manage return value */
2741 if (ret != LTTCOMM_OK) {
2742 goto error;
2743 }
2744
2745 kernel_wait_quiescent(kernel_tracer_fd);
2746 break;
2747 case LTTNG_DOMAIN_UST:
2748 {
2749 struct lttng_channel *attr;
2750 struct ltt_ust_channel *uchan;
2751 struct ltt_ust_session *usess = session->ust_session;
2752
2753 /* Get channel from global UST domain */
2754 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2755 channel_name);
2756 if (uchan == NULL) {
2757 /* Create default channel */
2758 attr = channel_new_default_attr(domain);
2759 if (attr == NULL) {
2760 ret = LTTCOMM_FATAL;
2761 goto error;
2762 }
2763 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2764 attr->name[NAME_MAX - 1] = '\0';
2765
2766 /* Use the internal command enable channel */
2767 ret = cmd_enable_channel(session, domain, attr);
2768 if (ret != LTTCOMM_OK) {
2769 free(attr);
2770 goto error;
2771 }
2772 free(attr);
2773
2774 /* Get the newly created channel reference back */
2775 uchan = trace_ust_find_channel_by_name(
2776 usess->domain_global.channels, channel_name);
2777 if (uchan == NULL) {
2778 /* Something is really wrong */
2779 ret = LTTCOMM_FATAL;
2780 goto error;
2781 }
2782 }
2783
2784 /* At this point, the session and channel exist on the tracer */
2785
2786 switch (event_type) {
2787 case LTTNG_EVENT_ALL:
2788 case LTTNG_EVENT_TRACEPOINT:
2789 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2790 if (ret != LTTCOMM_OK) {
2791 goto error;
2792 }
2793 break;
2794 default:
2795 ret = LTTCOMM_UST_ENABLE_FAIL;
2796 goto error;
2797 }
2798
2799 /* Manage return value */
2800 if (ret != LTTCOMM_OK) {
2801 goto error;
2802 }
2803
2804 break;
2805 }
2806 case LTTNG_DOMAIN_UST_EXEC_NAME:
2807 case LTTNG_DOMAIN_UST_PID:
2808 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2809 default:
2810 ret = LTTCOMM_NOT_IMPLEMENTED;
2811 goto error;
2812 }
2813
2814 ret = LTTCOMM_OK;
2815
2816 error:
2817 return ret;
2818 }
2819
2820 /*
2821 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2822 */
2823 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2824 {
2825 int ret;
2826 ssize_t nb_events = 0;
2827
2828 switch (domain) {
2829 case LTTNG_DOMAIN_KERNEL:
2830 nb_events = kernel_list_events(kernel_tracer_fd, events);
2831 if (nb_events < 0) {
2832 ret = LTTCOMM_KERN_LIST_FAIL;
2833 goto error;
2834 }
2835 break;
2836 case LTTNG_DOMAIN_UST:
2837 nb_events = ust_app_list_events(events);
2838 if (nb_events < 0) {
2839 ret = LTTCOMM_UST_LIST_FAIL;
2840 goto error;
2841 }
2842 break;
2843 default:
2844 ret = LTTCOMM_NOT_IMPLEMENTED;
2845 goto error;
2846 }
2847
2848 return nb_events;
2849
2850 error:
2851 /* Return negative value to differentiate return code */
2852 return -ret;
2853 }
2854
2855 /*
2856 * Command LTTNG_START_TRACE processed by the client thread.
2857 */
2858 static int cmd_start_trace(struct ltt_session *session)
2859 {
2860 int ret;
2861 struct ltt_kernel_session *ksession;
2862 struct ltt_ust_session *usess;
2863
2864 /* Short cut */
2865 ksession = session->kernel_session;
2866 usess = session->ust_session;
2867
2868 if (session->enabled)
2869 return LTTCOMM_UST_START_FAIL;
2870 session->enabled = 1;
2871
2872 /* Kernel tracing */
2873 if (ksession != NULL) {
2874 struct ltt_kernel_channel *kchan;
2875
2876 /* Open kernel metadata */
2877 if (ksession->metadata == NULL) {
2878 ret = kernel_open_metadata(ksession, ksession->trace_path);
2879 if (ret < 0) {
2880 ret = LTTCOMM_KERN_META_FAIL;
2881 goto error;
2882 }
2883 }
2884
2885 /* Open kernel metadata stream */
2886 if (ksession->metadata_stream_fd == 0) {
2887 ret = kernel_open_metadata_stream(ksession);
2888 if (ret < 0) {
2889 ERR("Kernel create metadata stream failed");
2890 ret = LTTCOMM_KERN_STREAM_FAIL;
2891 goto error;
2892 }
2893 }
2894
2895 /* For each channel */
2896 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2897 if (kchan->stream_count == 0) {
2898 ret = kernel_open_channel_stream(kchan);
2899 if (ret < 0) {
2900 ret = LTTCOMM_KERN_STREAM_FAIL;
2901 goto error;
2902 }
2903 /* Update the stream global counter */
2904 ksession->stream_count_global += ret;
2905 }
2906 }
2907
2908 /* Setup kernel consumer socket and send fds to it */
2909 ret = init_kernel_tracing(ksession);
2910 if (ret < 0) {
2911 ret = LTTCOMM_KERN_START_FAIL;
2912 goto error;
2913 }
2914
2915 /* This start the kernel tracing */
2916 ret = kernel_start_session(ksession);
2917 if (ret < 0) {
2918 ret = LTTCOMM_KERN_START_FAIL;
2919 goto error;
2920 }
2921
2922 /* Quiescent wait after starting trace */
2923 kernel_wait_quiescent(kernel_tracer_fd);
2924 }
2925
2926 /* Flag session that trace should start automatically */
2927 if (usess) {
2928 usess->start_trace = 1;
2929
2930 ret = ust_app_start_trace_all(usess);
2931 if (ret < 0) {
2932 ret = LTTCOMM_UST_START_FAIL;
2933 goto error;
2934 }
2935 }
2936
2937 ret = LTTCOMM_OK;
2938
2939 error:
2940 return ret;
2941 }
2942
2943 /*
2944 * Command LTTNG_STOP_TRACE processed by the client thread.
2945 */
2946 static int cmd_stop_trace(struct ltt_session *session)
2947 {
2948 int ret;
2949 struct ltt_kernel_channel *kchan;
2950 struct ltt_kernel_session *ksession;
2951 struct ltt_ust_session *usess;
2952
2953 /* Short cut */
2954 ksession = session->kernel_session;
2955 usess = session->ust_session;
2956
2957 if (!session->enabled)
2958 return LTTCOMM_UST_START_FAIL;
2959 session->enabled = 0;
2960
2961 /* Kernel tracer */
2962 if (ksession != NULL) {
2963 DBG("Stop kernel tracing");
2964
2965 /* Flush all buffers before stopping */
2966 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2967 if (ret < 0) {
2968 ERR("Kernel metadata flush failed");
2969 }
2970
2971 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2972 ret = kernel_flush_buffer(kchan);
2973 if (ret < 0) {
2974 ERR("Kernel flush buffer error");
2975 }
2976 }
2977
2978 ret = kernel_stop_session(ksession);
2979 if (ret < 0) {
2980 ret = LTTCOMM_KERN_STOP_FAIL;
2981 goto error;
2982 }
2983
2984 kernel_wait_quiescent(kernel_tracer_fd);
2985 }
2986
2987 if (usess) {
2988 usess->start_trace = 0;
2989
2990 ret = ust_app_stop_trace_all(usess);
2991 if (ret < 0) {
2992 ret = LTTCOMM_UST_START_FAIL;
2993 goto error;
2994 }
2995 }
2996
2997 ret = LTTCOMM_OK;
2998
2999 error:
3000 return ret;
3001 }
3002
3003 /*
3004 * Command LTTNG_CREATE_SESSION processed by the client thread.
3005 */
3006 static int cmd_create_session(char *name, char *path)
3007 {
3008 int ret;
3009
3010 ret = session_create(name, path);
3011 if (ret != LTTCOMM_OK) {
3012 goto error;
3013 }
3014
3015 ret = LTTCOMM_OK;
3016
3017 error:
3018 return ret;
3019 }
3020
3021 /*
3022 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3023 */
3024 static int cmd_destroy_session(struct ltt_session *session, char *name)
3025 {
3026 int ret;
3027
3028 /* Clean kernel session teardown */
3029 teardown_kernel_session(session);
3030 /* UST session teardown */
3031 teardown_ust_session(session);
3032
3033 /*
3034 * Must notify the kernel thread here to update it's poll setin order
3035 * to remove the channel(s)' fd just destroyed.
3036 */
3037 ret = notify_thread_pipe(kernel_poll_pipe[1]);
3038 if (ret < 0) {
3039 perror("write kernel poll pipe");
3040 }
3041
3042 ret = session_destroy(session);
3043
3044 return ret;
3045 }
3046
3047 /*
3048 * Command LTTNG_CALIBRATE processed by the client thread.
3049 */
3050 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3051 {
3052 int ret;
3053
3054 switch (domain) {
3055 case LTTNG_DOMAIN_KERNEL:
3056 {
3057 struct lttng_kernel_calibrate kcalibrate;
3058
3059 kcalibrate.type = calibrate->type;
3060 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3061 if (ret < 0) {
3062 ret = LTTCOMM_KERN_ENABLE_FAIL;
3063 goto error;
3064 }
3065 break;
3066 }
3067 default:
3068 /* TODO: Userspace tracing */
3069 ret = LTTCOMM_NOT_IMPLEMENTED;
3070 goto error;
3071 }
3072
3073 ret = LTTCOMM_OK;
3074
3075 error:
3076 return ret;
3077 }
3078
3079 /*
3080 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3081 */
3082 static int cmd_register_consumer(struct ltt_session *session, int domain,
3083 char *sock_path)
3084 {
3085 int ret, sock;
3086
3087 switch (domain) {
3088 case LTTNG_DOMAIN_KERNEL:
3089 /* Can't register a consumer if there is already one */
3090 if (session->kernel_session->consumer_fd != 0) {
3091 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3092 goto error;
3093 }
3094
3095 sock = lttcomm_connect_unix_sock(sock_path);
3096 if (sock < 0) {
3097 ret = LTTCOMM_CONNECT_FAIL;
3098 goto error;
3099 }
3100
3101 session->kernel_session->consumer_fd = sock;
3102 break;
3103 default:
3104 /* TODO: Userspace tracing */
3105 ret = LTTCOMM_NOT_IMPLEMENTED;
3106 goto error;
3107 }
3108
3109 ret = LTTCOMM_OK;
3110
3111 error:
3112 return ret;
3113 }
3114
3115 /*
3116 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3117 */
3118 static ssize_t cmd_list_domains(struct ltt_session *session,
3119 struct lttng_domain **domains)
3120 {
3121 int ret, index = 0;
3122 ssize_t nb_dom = 0;
3123
3124 if (session->kernel_session != NULL) {
3125 DBG3("Listing domains found kernel domain");
3126 nb_dom++;
3127 }
3128
3129 if (session->ust_session != NULL) {
3130 DBG3("Listing domains found UST global domain");
3131 nb_dom++;
3132 }
3133
3134 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3135 if (*domains == NULL) {
3136 ret = -LTTCOMM_FATAL;
3137 goto error;
3138 }
3139
3140 if (session->kernel_session != NULL) {
3141 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3142 index++;
3143 }
3144
3145 if (session->ust_session != NULL) {
3146 (*domains)[index].type = LTTNG_DOMAIN_UST;
3147 index++;
3148 }
3149
3150 return nb_dom;
3151
3152 error:
3153 return ret;
3154 }
3155
3156 /*
3157 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3158 */
3159 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3160 struct lttng_channel **channels)
3161 {
3162 int ret;
3163 ssize_t nb_chan = 0;
3164
3165 switch (domain) {
3166 case LTTNG_DOMAIN_KERNEL:
3167 if (session->kernel_session != NULL) {
3168 nb_chan = session->kernel_session->channel_count;
3169 }
3170 DBG3("Number of kernel channels %zd", nb_chan);
3171 break;
3172 case LTTNG_DOMAIN_UST:
3173 if (session->ust_session != NULL) {
3174 nb_chan = hashtable_get_count(
3175 session->ust_session->domain_global.channels);
3176 }
3177 DBG3("Number of UST global channels %zd", nb_chan);
3178 break;
3179 default:
3180 *channels = NULL;
3181 ret = -LTTCOMM_NOT_IMPLEMENTED;
3182 goto error;
3183 }
3184
3185 if (nb_chan > 0) {
3186 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3187 if (*channels == NULL) {
3188 ret = -LTTCOMM_FATAL;
3189 goto error;
3190 }
3191
3192 list_lttng_channels(domain, session, *channels);
3193 } else {
3194 *channels = NULL;
3195 }
3196
3197 return nb_chan;
3198
3199 error:
3200 return ret;
3201 }
3202
3203 /*
3204 * Command LTTNG_LIST_EVENTS processed by the client thread.
3205 */
3206 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3207 char *channel_name, struct lttng_event **events)
3208 {
3209 int ret = 0;
3210 ssize_t nb_event = 0;
3211
3212 switch (domain) {
3213 case LTTNG_DOMAIN_KERNEL:
3214 if (session->kernel_session != NULL) {
3215 nb_event = list_lttng_kernel_events(channel_name,
3216 session->kernel_session, events);
3217 }
3218 break;
3219 case LTTNG_DOMAIN_UST:
3220 {
3221 if (session->ust_session != NULL) {
3222 nb_event = list_lttng_ust_global_events(channel_name,
3223 &session->ust_session->domain_global, events);
3224 }
3225 break;
3226 }
3227 default:
3228 ret = -LTTCOMM_NOT_IMPLEMENTED;
3229 goto error;
3230 }
3231
3232 ret = nb_event;
3233
3234 error:
3235 return ret;
3236 }
3237
3238 /*
3239 * Process the command requested by the lttng client within the command
3240 * context structure. This function make sure that the return structure (llm)
3241 * is set and ready for transmission before returning.
3242 *
3243 * Return any error encountered or 0 for success.
3244 */
3245 static int process_client_msg(struct command_ctx *cmd_ctx)
3246 {
3247 int ret = LTTCOMM_OK;
3248 int need_tracing_session = 1;
3249
3250 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3251
3252 /*
3253 * Check for command that don't needs to allocate a returned payload. We do
3254 * this here so we don't have to make the call for no payload at each
3255 * command.
3256 */
3257 switch(cmd_ctx->lsm->cmd_type) {
3258 case LTTNG_LIST_SESSIONS:
3259 case LTTNG_LIST_TRACEPOINTS:
3260 case LTTNG_LIST_DOMAINS:
3261 case LTTNG_LIST_CHANNELS:
3262 case LTTNG_LIST_EVENTS:
3263 break;
3264 default:
3265 /* Setup lttng message with no payload */
3266 ret = setup_lttng_msg(cmd_ctx, 0);
3267 if (ret < 0) {
3268 /* This label does not try to unlock the session */
3269 goto init_setup_error;
3270 }
3271 }
3272
3273 /* Commands that DO NOT need a session. */
3274 switch (cmd_ctx->lsm->cmd_type) {
3275 case LTTNG_CALIBRATE:
3276 case LTTNG_CREATE_SESSION:
3277 case LTTNG_LIST_SESSIONS:
3278 case LTTNG_LIST_TRACEPOINTS:
3279 need_tracing_session = 0;
3280 break;
3281 default:
3282 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3283 session_lock_list();
3284 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3285 session_unlock_list();
3286 if (cmd_ctx->session == NULL) {
3287 if (cmd_ctx->lsm->session.name != NULL) {
3288 ret = LTTCOMM_SESS_NOT_FOUND;
3289 } else {
3290 /* If no session name specified */
3291 ret = LTTCOMM_SELECT_SESS;
3292 }
3293 goto error;
3294 } else {
3295 /* Acquire lock for the session */
3296 session_lock(cmd_ctx->session);
3297 }
3298 break;
3299 }
3300
3301 /*
3302 * Check domain type for specific "pre-action".
3303 */
3304 switch (cmd_ctx->lsm->domain.type) {
3305 case LTTNG_DOMAIN_KERNEL:
3306 /* Kernel tracer check */
3307 if (kernel_tracer_fd == 0) {
3308 /* Basically, load kernel tracer modules */
3309 init_kernel_tracer();
3310 if (kernel_tracer_fd == 0) {
3311 ret = LTTCOMM_KERN_NA;
3312 goto error;
3313 }
3314 }
3315
3316 /* Need a session for kernel command */
3317 if (need_tracing_session) {
3318 if (cmd_ctx->session->kernel_session == NULL) {
3319 ret = create_kernel_session(cmd_ctx->session);
3320 if (ret < 0) {
3321 ret = LTTCOMM_KERN_SESS_FAIL;
3322 goto error;
3323 }
3324 }
3325
3326 /* Start the kernel consumer daemon */
3327 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3328 if (kconsumer_data.pid == 0 &&
3329 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3330 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3331 ret = start_consumerd(&kconsumer_data);
3332 if (ret < 0) {
3333 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3334 goto error;
3335 }
3336 } else {
3337 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3338 }
3339 }
3340 break;
3341 case LTTNG_DOMAIN_UST:
3342 {
3343 if (need_tracing_session) {
3344 if (cmd_ctx->session->ust_session == NULL) {
3345 ret = create_ust_session(cmd_ctx->session,
3346 &cmd_ctx->lsm->domain);
3347 if (ret != LTTCOMM_OK) {
3348 goto error;