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[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 tmp[i].type = LTTNG_EVENT_TRACEPOINT_LOGLEVEL;
2097 break;
2098 }
2099 i++;
2100 }
2101
2102 ret = nb_event;
2103 *events = tmp;
2104
2105 error:
2106 rcu_read_unlock();
2107 return ret;
2108 }
2109
2110 /*
2111 * Fill lttng_event array of all kernel events in the channel.
2112 */
2113 static int list_lttng_kernel_events(char *channel_name,
2114 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2115 {
2116 int i = 0, ret;
2117 unsigned int nb_event;
2118 struct ltt_kernel_event *event;
2119 struct ltt_kernel_channel *kchan;
2120
2121 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2122 if (kchan == NULL) {
2123 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2124 goto error;
2125 }
2126
2127 nb_event = kchan->event_count;
2128
2129 DBG("Listing events for channel %s", kchan->channel->name);
2130
2131 if (nb_event == 0) {
2132 ret = nb_event;
2133 goto error;
2134 }
2135
2136 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2137 if (*events == NULL) {
2138 ret = LTTCOMM_FATAL;
2139 goto error;
2140 }
2141
2142 /* Kernel channels */
2143 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2144 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2145 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2146 (*events)[i].enabled = event->enabled;
2147 switch (event->event->instrumentation) {
2148 case LTTNG_KERNEL_TRACEPOINT:
2149 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2150 break;
2151 case LTTNG_KERNEL_KPROBE:
2152 case LTTNG_KERNEL_KRETPROBE:
2153 (*events)[i].type = LTTNG_EVENT_PROBE;
2154 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2155 sizeof(struct lttng_kernel_kprobe));
2156 break;
2157 case LTTNG_KERNEL_FUNCTION:
2158 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2159 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2160 sizeof(struct lttng_kernel_function));
2161 break;
2162 case LTTNG_KERNEL_NOOP:
2163 (*events)[i].type = LTTNG_EVENT_NOOP;
2164 break;
2165 case LTTNG_KERNEL_SYSCALL:
2166 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2167 break;
2168 case LTTNG_KERNEL_ALL:
2169 assert(0);
2170 break;
2171 }
2172 i++;
2173 }
2174
2175 return nb_event;
2176
2177 error:
2178 return ret;
2179 }
2180
2181 /*
2182 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2183 */
2184 static int cmd_disable_channel(struct ltt_session *session,
2185 int domain, char *channel_name)
2186 {
2187 int ret;
2188 struct ltt_ust_session *usess;
2189
2190 usess = session->ust_session;
2191
2192 switch (domain) {
2193 case LTTNG_DOMAIN_KERNEL:
2194 {
2195 ret = channel_kernel_disable(session->kernel_session,
2196 channel_name);
2197 if (ret != LTTCOMM_OK) {
2198 goto error;
2199 }
2200
2201 kernel_wait_quiescent(kernel_tracer_fd);
2202 break;
2203 }
2204 case LTTNG_DOMAIN_UST:
2205 {
2206 struct ltt_ust_channel *uchan;
2207
2208 /* Get channel in global UST domain HT */
2209 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2210 channel_name);
2211 if (uchan == NULL) {
2212 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2213 goto error;
2214 }
2215
2216 /* Already disabled */
2217 if (!uchan->enabled) {
2218 DBG2("UST channel %s already disabled", channel_name);
2219 break;
2220 }
2221
2222 ret = ust_app_disable_channel_glb(usess, uchan);
2223 if (ret < 0) {
2224 ret = LTTCOMM_UST_DISABLE_FAIL;
2225 goto error;
2226 }
2227
2228 uchan->enabled = 0;
2229
2230 break;
2231 }
2232 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2233 case LTTNG_DOMAIN_UST_EXEC_NAME:
2234 case LTTNG_DOMAIN_UST_PID:
2235 ret = LTTCOMM_NOT_IMPLEMENTED;
2236 goto error;
2237 default:
2238 ret = LTTCOMM_UNKNOWN_DOMAIN;
2239 goto error;
2240 }
2241
2242 ret = LTTCOMM_OK;
2243
2244 error:
2245 return ret;
2246 }
2247
2248 /*
2249 * Copy channel from attributes and set it in the application channel list.
2250 */
2251 /*
2252 static int copy_ust_channel_to_app(struct ltt_ust_session *usess,
2253 struct lttng_channel *attr, struct ust_app *app)
2254 {
2255 int ret;
2256 struct ltt_ust_channel *uchan, *new_chan;
2257
2258 uchan = trace_ust_get_channel_by_key(usess->channels, attr->name);
2259 if (uchan == NULL) {
2260 ret = LTTCOMM_FATAL;
2261 goto error;
2262 }
2263
2264 new_chan = trace_ust_create_channel(attr, usess->path);
2265 if (new_chan == NULL) {
2266 PERROR("malloc ltt_ust_channel");
2267 ret = LTTCOMM_FATAL;
2268 goto error;
2269 }
2270
2271 ret = channel_ust_copy(new_chan, uchan);
2272 if (ret < 0) {
2273 ret = LTTCOMM_FATAL;
2274 goto error;
2275 }
2276
2277 error:
2278 return ret;
2279 }
2280 */
2281
2282 /*
2283 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2284 */
2285 static int cmd_enable_channel(struct ltt_session *session,
2286 int domain, struct lttng_channel *attr)
2287 {
2288 int ret;
2289 struct ltt_ust_session *usess = session->ust_session;
2290
2291 DBG("Enabling channel %s for session %s", attr->name, session->name);
2292
2293 switch (domain) {
2294 case LTTNG_DOMAIN_KERNEL:
2295 {
2296 struct ltt_kernel_channel *kchan;
2297
2298 kchan = trace_kernel_get_channel_by_name(attr->name,
2299 session->kernel_session);
2300 if (kchan == NULL) {
2301 ret = channel_kernel_create(session->kernel_session,
2302 attr, kernel_poll_pipe[1]);
2303 } else {
2304 ret = channel_kernel_enable(session->kernel_session, kchan);
2305 }
2306
2307 if (ret != LTTCOMM_OK) {
2308 goto error;
2309 }
2310
2311 kernel_wait_quiescent(kernel_tracer_fd);
2312 break;
2313 }
2314 case LTTNG_DOMAIN_UST:
2315 {
2316 struct ltt_ust_channel *uchan;
2317
2318 DBG2("Enabling channel for LTTNG_DOMAIN_UST");
2319
2320 /* Get channel in global UST domain HT */
2321 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2322 attr->name);
2323 if (uchan == NULL) {
2324 uchan = trace_ust_create_channel(attr, usess->pathname);
2325 if (uchan == NULL) {
2326 ret = LTTCOMM_UST_CHAN_FAIL;
2327 goto error;
2328 }
2329
2330 /* Add channel to all registered applications */
2331 ret = ust_app_create_channel_glb(usess, uchan);
2332 if (ret != 0) {
2333 ret = LTTCOMM_UST_CHAN_FAIL;
2334 goto error;
2335 }
2336
2337 rcu_read_lock();
2338 hashtable_add_unique(usess->domain_global.channels, &uchan->node);
2339 rcu_read_unlock();
2340
2341 DBG2("UST channel %s added to global domain HT", attr->name);
2342 } else {
2343 /* If already enabled, everything is OK */
2344 if (uchan->enabled) {
2345 break;
2346 }
2347
2348 ret = ust_app_enable_channel_glb(usess, uchan);
2349 if (ret < 0) {
2350 if (ret != -EEXIST) {
2351 ret = LTTCOMM_UST_CHAN_ENABLE_FAIL;
2352 goto error;
2353 } else {
2354 ret = LTTCOMM_OK;
2355 }
2356 }
2357 }
2358
2359 uchan->enabled = 1;
2360
2361 break;
2362 }
2363 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2364 case LTTNG_DOMAIN_UST_EXEC_NAME:
2365 case LTTNG_DOMAIN_UST_PID:
2366 ret = LTTCOMM_NOT_IMPLEMENTED;
2367 goto error;
2368 default:
2369 ret = LTTCOMM_UNKNOWN_DOMAIN;
2370 goto error;
2371 }
2372
2373 ret = LTTCOMM_OK;
2374
2375 error:
2376 return ret;
2377 }
2378
2379 /*
2380 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2381 */
2382 static int cmd_disable_event(struct ltt_session *session, int domain,
2383 char *channel_name, char *event_name)
2384 {
2385 int ret;
2386
2387 switch (domain) {
2388 case LTTNG_DOMAIN_KERNEL:
2389 {
2390 struct ltt_kernel_channel *kchan;
2391 struct ltt_kernel_session *ksess;
2392
2393 ksess = session->kernel_session;
2394
2395 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2396 if (kchan == NULL) {
2397 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2398 goto error;
2399 }
2400
2401 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2402 if (ret != LTTCOMM_OK) {
2403 goto error;
2404 }
2405
2406 kernel_wait_quiescent(kernel_tracer_fd);
2407 break;
2408 }
2409 case LTTNG_DOMAIN_UST:
2410 {
2411 struct ltt_ust_session *usess;
2412 struct ltt_ust_channel *uchan;
2413 struct ltt_ust_event *uevent;
2414
2415 usess = session->ust_session;
2416
2417 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2418 channel_name);
2419 if (uchan == NULL) {
2420 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2421 goto error;
2422 }
2423
2424 uevent = trace_ust_find_event_by_name(uchan->events, event_name);
2425 if (uevent == NULL) {
2426 ret = LTTCOMM_UST_EVENT_NOT_FOUND;
2427 goto error;
2428 }
2429
2430 ret = ust_app_disable_event_glb(usess, uchan, uevent);
2431 if (ret < 0) {
2432 ret = LTTCOMM_UST_DISABLE_FAIL;
2433 goto error;
2434 }
2435
2436 uevent->enabled = 0;
2437
2438 DBG2("Disable UST event %s in channel %s completed", event_name,
2439 channel_name);
2440
2441 break;
2442 }
2443 case LTTNG_DOMAIN_UST_EXEC_NAME:
2444 case LTTNG_DOMAIN_UST_PID:
2445 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2446 default:
2447 ret = LTTCOMM_NOT_IMPLEMENTED;
2448 goto error;
2449 }
2450
2451 ret = LTTCOMM_OK;
2452
2453 error:
2454 return ret;
2455 }
2456
2457 /*
2458 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2459 */
2460 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2461 char *channel_name)
2462 {
2463 int ret;
2464
2465 switch (domain) {
2466 case LTTNG_DOMAIN_KERNEL:
2467 {
2468 struct ltt_kernel_session *ksess;
2469 struct ltt_kernel_channel *kchan;
2470
2471 ksess = session->kernel_session;
2472
2473 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2474 if (kchan == NULL) {
2475 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2476 goto error;
2477 }
2478
2479 ret = event_kernel_disable_all(ksess, kchan);
2480 if (ret != LTTCOMM_OK) {
2481 goto error;
2482 }
2483
2484 kernel_wait_quiescent(kernel_tracer_fd);
2485 break;
2486 }
2487 case LTTNG_DOMAIN_UST:
2488 {
2489 struct ltt_ust_session *usess;
2490 struct ltt_ust_channel *uchan;
2491
2492 usess = session->ust_session;
2493
2494 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2495 channel_name);
2496 if (uchan == NULL) {
2497 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2498 goto error;
2499 }
2500
2501 ret = ust_app_disable_all_event_glb(usess, uchan);
2502 if (ret < 0) {
2503 ret = LTTCOMM_UST_DISABLE_FAIL;
2504 goto error;
2505 }
2506
2507 DBG2("Disable all UST event in channel %s completed", channel_name);
2508
2509 break;
2510 }
2511 case LTTNG_DOMAIN_UST_EXEC_NAME:
2512 case LTTNG_DOMAIN_UST_PID:
2513 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2514 default:
2515 ret = LTTCOMM_NOT_IMPLEMENTED;
2516 goto error;
2517 }
2518
2519 ret = LTTCOMM_OK;
2520
2521 error:
2522 return ret;
2523 }
2524
2525 /*
2526 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2527 */
2528 static int cmd_add_context(struct ltt_session *session, int domain,
2529 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2530 {
2531 int ret;
2532
2533 switch (domain) {
2534 case LTTNG_DOMAIN_KERNEL:
2535 /* Add kernel context to kernel tracer */
2536 ret = context_kernel_add(session->kernel_session, ctx,
2537 event_name, channel_name);
2538 if (ret != LTTCOMM_OK) {
2539 goto error;
2540 }
2541 break;
2542 case LTTNG_DOMAIN_UST:
2543 {
2544 struct ltt_ust_session *usess = session->ust_session;
2545
2546 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2547 if (ret != LTTCOMM_OK) {
2548 goto error;
2549 }
2550 break;
2551 }
2552 case LTTNG_DOMAIN_UST_EXEC_NAME:
2553 case LTTNG_DOMAIN_UST_PID:
2554 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2555 default:
2556 ret = LTTCOMM_NOT_IMPLEMENTED;
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 * TODO: currently, both events and loglevels are kept within the same
2570 * namespace for UST global registry/app registery, so if an event
2571 * happen to have the same name as the loglevel (very unlikely though),
2572 * and an attempt is made to enable/disable both in the same session,
2573 * the first to be created will be the only one allowed to exist.
2574 */
2575 static int cmd_enable_event(struct ltt_session *session, int domain,
2576 char *channel_name, struct lttng_event *event)
2577 {
2578 int ret;
2579 struct lttng_channel *attr;
2580 struct ltt_ust_session *usess = session->ust_session;
2581
2582 switch (domain) {
2583 case LTTNG_DOMAIN_KERNEL:
2584 {
2585 struct ltt_kernel_channel *kchan;
2586
2587 kchan = trace_kernel_get_channel_by_name(channel_name,
2588 session->kernel_session);
2589 if (kchan == NULL) {
2590 attr = channel_new_default_attr(domain);
2591 if (attr == NULL) {
2592 ret = LTTCOMM_FATAL;
2593 goto error;
2594 }
2595 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2596
2597 /* This call will notify the kernel thread */
2598 ret = channel_kernel_create(session->kernel_session,
2599 attr, kernel_poll_pipe[1]);
2600 if (ret != LTTCOMM_OK) {
2601 free(attr);
2602 goto error;
2603 }
2604 free(attr);
2605 }
2606
2607 /* Get the newly created kernel channel pointer */
2608 kchan = trace_kernel_get_channel_by_name(channel_name,
2609 session->kernel_session);
2610 if (kchan == NULL) {
2611 /* This sould not happen... */
2612 ret = LTTCOMM_FATAL;
2613 goto error;
2614 }
2615
2616 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2617 event);
2618 if (ret != LTTCOMM_OK) {
2619 goto error;
2620 }
2621
2622 kernel_wait_quiescent(kernel_tracer_fd);
2623 break;
2624 }
2625 case LTTNG_DOMAIN_UST:
2626 {
2627 struct lttng_channel *attr;
2628 struct ltt_ust_channel *uchan;
2629
2630 /* Get channel from global UST domain */
2631 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2632 channel_name);
2633 if (uchan == NULL) {
2634 /* Create default channel */
2635 attr = channel_new_default_attr(domain);
2636 if (attr == NULL) {
2637 ret = LTTCOMM_FATAL;
2638 goto error;
2639 }
2640 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2641 attr->name[NAME_MAX - 1] = '\0';
2642
2643 /* Use the internal command enable channel */
2644 ret = cmd_enable_channel(session, domain, attr);
2645 if (ret != LTTCOMM_OK) {
2646 free(attr);
2647 goto error;
2648 }
2649 free(attr);
2650
2651 /* Get the newly created channel reference back */
2652 uchan = trace_ust_find_channel_by_name(
2653 usess->domain_global.channels, channel_name);
2654 if (uchan == NULL) {
2655 /* Something is really wrong */
2656 ret = LTTCOMM_FATAL;
2657 goto error;
2658 }
2659 }
2660
2661 /* At this point, the session and channel exist on the tracer */
2662
2663 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2664 if (ret != LTTCOMM_OK) {
2665 goto error;
2666 }
2667 break;
2668 }
2669 case LTTNG_DOMAIN_UST_EXEC_NAME:
2670 case LTTNG_DOMAIN_UST_PID:
2671 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2672 default:
2673 ret = LTTCOMM_NOT_IMPLEMENTED;
2674 goto error;
2675 }
2676
2677 ret = LTTCOMM_OK;
2678
2679 error:
2680 return ret;
2681 }
2682
2683 /*
2684 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2685 */
2686 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2687 char *channel_name, int event_type)
2688 {
2689 int ret;
2690 struct ltt_kernel_channel *kchan;
2691
2692 switch (domain) {
2693 case LTTNG_DOMAIN_KERNEL:
2694 kchan = trace_kernel_get_channel_by_name(channel_name,
2695 session->kernel_session);
2696 if (kchan == NULL) {
2697 /* This call will notify the kernel thread */
2698 ret = channel_kernel_create(session->kernel_session, NULL,
2699 kernel_poll_pipe[1]);
2700 if (ret != LTTCOMM_OK) {
2701 goto error;
2702 }
2703
2704 /* Get the newly created kernel channel pointer */
2705 kchan = trace_kernel_get_channel_by_name(channel_name,
2706 session->kernel_session);
2707 if (kchan == NULL) {
2708 /* This sould not happen... */
2709 ret = LTTCOMM_FATAL;
2710 goto error;
2711 }
2712
2713 }
2714
2715 switch (event_type) {
2716 case LTTNG_KERNEL_SYSCALL:
2717 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2718 kchan, kernel_tracer_fd);
2719 break;
2720 case LTTNG_KERNEL_TRACEPOINT:
2721 /*
2722 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2723 * events already registered to the channel.
2724 */
2725 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2726 kchan, kernel_tracer_fd);
2727 break;
2728 case LTTNG_KERNEL_ALL:
2729 /* Enable syscalls and tracepoints */
2730 ret = event_kernel_enable_all(session->kernel_session,
2731 kchan, kernel_tracer_fd);
2732 break;
2733 default:
2734 ret = LTTCOMM_KERN_ENABLE_FAIL;
2735 goto error;
2736 }
2737
2738 /* Manage return value */
2739 if (ret != LTTCOMM_OK) {
2740 goto error;
2741 }
2742
2743 kernel_wait_quiescent(kernel_tracer_fd);
2744 break;
2745 default:
2746 /* TODO: Userspace tracing */
2747 ret = LTTCOMM_NOT_IMPLEMENTED;
2748 goto error;
2749 }
2750
2751 ret = LTTCOMM_OK;
2752
2753 error:
2754 return ret;
2755 }
2756
2757 /*
2758 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2759 */
2760 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2761 {
2762 int ret;
2763 ssize_t nb_events = 0;
2764
2765 switch (domain) {
2766 case LTTNG_DOMAIN_KERNEL:
2767 nb_events = kernel_list_events(kernel_tracer_fd, events);
2768 if (nb_events < 0) {
2769 ret = LTTCOMM_KERN_LIST_FAIL;
2770 goto error;
2771 }
2772 break;
2773 case LTTNG_DOMAIN_UST:
2774 nb_events = ust_app_list_events(events);
2775 if (nb_events < 0) {
2776 ret = LTTCOMM_UST_LIST_FAIL;
2777 goto error;
2778 }
2779 break;
2780 default:
2781 ret = LTTCOMM_NOT_IMPLEMENTED;
2782 goto error;
2783 }
2784
2785 return nb_events;
2786
2787 error:
2788 /* Return negative value to differentiate return code */
2789 return -ret;
2790 }
2791
2792 /*
2793 * Command LTTNG_START_TRACE processed by the client thread.
2794 */
2795 static int cmd_start_trace(struct ltt_session *session)
2796 {
2797 int ret;
2798 struct ltt_kernel_session *ksession;
2799 struct ltt_ust_session *usess;
2800
2801 /* Short cut */
2802 ksession = session->kernel_session;
2803 usess = session->ust_session;
2804
2805 if (session->enabled)
2806 return LTTCOMM_UST_START_FAIL;
2807 session->enabled = 1;
2808
2809 /* Kernel tracing */
2810 if (ksession != NULL) {
2811 struct ltt_kernel_channel *kchan;
2812
2813 /* Open kernel metadata */
2814 if (ksession->metadata == NULL) {
2815 ret = kernel_open_metadata(ksession, ksession->trace_path);
2816 if (ret < 0) {
2817 ret = LTTCOMM_KERN_META_FAIL;
2818 goto error;
2819 }
2820 }
2821
2822 /* Open kernel metadata stream */
2823 if (ksession->metadata_stream_fd == 0) {
2824 ret = kernel_open_metadata_stream(ksession);
2825 if (ret < 0) {
2826 ERR("Kernel create metadata stream failed");
2827 ret = LTTCOMM_KERN_STREAM_FAIL;
2828 goto error;
2829 }
2830 }
2831
2832 /* For each channel */
2833 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2834 if (kchan->stream_count == 0) {
2835 ret = kernel_open_channel_stream(kchan);
2836 if (ret < 0) {
2837 ret = LTTCOMM_KERN_STREAM_FAIL;
2838 goto error;
2839 }
2840 /* Update the stream global counter */
2841 ksession->stream_count_global += ret;
2842 }
2843 }
2844
2845 /* Setup kernel consumer socket and send fds to it */
2846 ret = init_kernel_tracing(ksession);
2847 if (ret < 0) {
2848 ret = LTTCOMM_KERN_START_FAIL;
2849 goto error;
2850 }
2851
2852 /* This start the kernel tracing */
2853 ret = kernel_start_session(ksession);
2854 if (ret < 0) {
2855 ret = LTTCOMM_KERN_START_FAIL;
2856 goto error;
2857 }
2858
2859 /* Quiescent wait after starting trace */
2860 kernel_wait_quiescent(kernel_tracer_fd);
2861 }
2862
2863 /* Flag session that trace should start automatically */
2864 if (usess) {
2865 usess->start_trace = 1;
2866
2867 ret = ust_app_start_trace_all(usess);
2868 if (ret < 0) {
2869 ret = LTTCOMM_UST_START_FAIL;
2870 goto error;
2871 }
2872 }
2873
2874 ret = LTTCOMM_OK;
2875
2876 error:
2877 return ret;
2878 }
2879
2880 /*
2881 * Command LTTNG_STOP_TRACE processed by the client thread.
2882 */
2883 static int cmd_stop_trace(struct ltt_session *session)
2884 {
2885 int ret;
2886 struct ltt_kernel_channel *kchan;
2887 struct ltt_kernel_session *ksession;
2888 struct ltt_ust_session *usess;
2889
2890 /* Short cut */
2891 ksession = session->kernel_session;
2892 usess = session->ust_session;
2893
2894 if (!session->enabled)
2895 return LTTCOMM_UST_START_FAIL;
2896 session->enabled = 0;
2897
2898 /* Kernel tracer */
2899 if (ksession != NULL) {
2900 DBG("Stop kernel tracing");
2901
2902 /* Flush all buffers before stopping */
2903 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2904 if (ret < 0) {
2905 ERR("Kernel metadata flush failed");
2906 }
2907
2908 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2909 ret = kernel_flush_buffer(kchan);
2910 if (ret < 0) {
2911 ERR("Kernel flush buffer error");
2912 }
2913 }
2914
2915 ret = kernel_stop_session(ksession);
2916 if (ret < 0) {
2917 ret = LTTCOMM_KERN_STOP_FAIL;
2918 goto error;
2919 }
2920
2921 kernel_wait_quiescent(kernel_tracer_fd);
2922 }
2923
2924 if (usess) {
2925 usess->start_trace = 0;
2926
2927 ret = ust_app_stop_trace_all(usess);
2928 if (ret < 0) {
2929 ret = LTTCOMM_UST_START_FAIL;
2930 goto error;
2931 }
2932 }
2933
2934 ret = LTTCOMM_OK;
2935
2936 error:
2937 return ret;
2938 }
2939
2940 /*
2941 * Command LTTNG_CREATE_SESSION processed by the client thread.
2942 */
2943 static int cmd_create_session(char *name, char *path)
2944 {
2945 int ret;
2946
2947 ret = session_create(name, path);
2948 if (ret != LTTCOMM_OK) {
2949 goto error;
2950 }
2951
2952 ret = LTTCOMM_OK;
2953
2954 error:
2955 return ret;
2956 }
2957
2958 /*
2959 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2960 */
2961 static int cmd_destroy_session(struct ltt_session *session, char *name)
2962 {
2963 int ret;
2964
2965 /* Clean kernel session teardown */
2966 teardown_kernel_session(session);
2967 /* UST session teardown */
2968 teardown_ust_session(session);
2969
2970 /*
2971 * Must notify the kernel thread here to update it's poll setin order
2972 * to remove the channel(s)' fd just destroyed.
2973 */
2974 ret = notify_thread_pipe(kernel_poll_pipe[1]);
2975 if (ret < 0) {
2976 perror("write kernel poll pipe");
2977 }
2978
2979 ret = session_destroy(session);
2980
2981 return ret;
2982 }
2983
2984 /*
2985 * Command LTTNG_CALIBRATE processed by the client thread.
2986 */
2987 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
2988 {
2989 int ret;
2990
2991 switch (domain) {
2992 case LTTNG_DOMAIN_KERNEL:
2993 {
2994 struct lttng_kernel_calibrate kcalibrate;
2995
2996 kcalibrate.type = calibrate->type;
2997 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
2998 if (ret < 0) {
2999 ret = LTTCOMM_KERN_ENABLE_FAIL;
3000 goto error;
3001 }
3002 break;
3003 }
3004 default:
3005 /* TODO: Userspace tracing */
3006 ret = LTTCOMM_NOT_IMPLEMENTED;
3007 goto error;
3008 }
3009
3010 ret = LTTCOMM_OK;
3011
3012 error:
3013 return ret;
3014 }
3015
3016 /*
3017 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3018 */
3019 static int cmd_register_consumer(struct ltt_session *session, int domain,
3020 char *sock_path)
3021 {
3022 int ret, sock;
3023
3024 switch (domain) {
3025 case LTTNG_DOMAIN_KERNEL:
3026 /* Can't register a consumer if there is already one */
3027 if (session->kernel_session->consumer_fd != 0) {
3028 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3029 goto error;
3030 }
3031
3032 sock = lttcomm_connect_unix_sock(sock_path);
3033 if (sock < 0) {
3034 ret = LTTCOMM_CONNECT_FAIL;
3035 goto error;
3036 }
3037
3038 session->kernel_session->consumer_fd = sock;
3039 break;
3040 default:
3041 /* TODO: Userspace tracing */
3042 ret = LTTCOMM_NOT_IMPLEMENTED;
3043 goto error;
3044 }
3045
3046 ret = LTTCOMM_OK;
3047
3048 error:
3049 return ret;
3050 }
3051
3052 /*
3053 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3054 */
3055 static ssize_t cmd_list_domains(struct ltt_session *session,
3056 struct lttng_domain **domains)
3057 {
3058 int ret, index = 0;
3059 ssize_t nb_dom = 0;
3060
3061 if (session->kernel_session != NULL) {
3062 DBG3("Listing domains found kernel domain");
3063 nb_dom++;
3064 }
3065
3066 if (session->ust_session != NULL) {
3067 DBG3("Listing domains found UST global domain");
3068 nb_dom++;
3069 }
3070
3071 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3072 if (*domains == NULL) {
3073 ret = -LTTCOMM_FATAL;
3074 goto error;
3075 }
3076
3077 if (session->kernel_session != NULL) {
3078 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3079 index++;
3080 }
3081
3082 if (session->ust_session != NULL) {
3083 (*domains)[index].type = LTTNG_DOMAIN_UST;
3084 index++;
3085 }
3086
3087 return nb_dom;
3088
3089 error:
3090 return ret;
3091 }
3092
3093 /*
3094 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3095 */
3096 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3097 struct lttng_channel **channels)
3098 {
3099 int ret;
3100 ssize_t nb_chan = 0;
3101
3102 switch (domain) {
3103 case LTTNG_DOMAIN_KERNEL:
3104 if (session->kernel_session != NULL) {
3105 nb_chan = session->kernel_session->channel_count;
3106 }
3107 DBG3("Number of kernel channels %zd", nb_chan);
3108 break;
3109 case LTTNG_DOMAIN_UST:
3110 if (session->ust_session != NULL) {
3111 nb_chan = hashtable_get_count(
3112 session->ust_session->domain_global.channels);
3113 }
3114 DBG3("Number of UST global channels %zd", nb_chan);
3115 break;
3116 default:
3117 *channels = NULL;
3118 ret = -LTTCOMM_NOT_IMPLEMENTED;
3119 goto error;
3120 }
3121
3122 if (nb_chan > 0) {
3123 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3124 if (*channels == NULL) {
3125 ret = -LTTCOMM_FATAL;
3126 goto error;
3127 }
3128
3129 list_lttng_channels(domain, session, *channels);
3130 } else {
3131 *channels = NULL;
3132 }
3133
3134 return nb_chan;
3135
3136 error:
3137 return ret;
3138 }
3139
3140 /*
3141 * Command LTTNG_LIST_EVENTS processed by the client thread.
3142 */
3143 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3144 char *channel_name, struct lttng_event **events)
3145 {
3146 int ret = 0;
3147 ssize_t nb_event = 0;
3148
3149 switch (domain) {
3150 case LTTNG_DOMAIN_KERNEL:
3151 if (session->kernel_session != NULL) {
3152 nb_event = list_lttng_kernel_events(channel_name,
3153 session->kernel_session, events);
3154 }
3155 break;
3156 case LTTNG_DOMAIN_UST:
3157 {
3158 if (session->ust_session != NULL) {
3159 nb_event = list_lttng_ust_global_events(channel_name,
3160 &session->ust_session->domain_global, events);
3161 }
3162 break;
3163 }
3164 default:
3165 ret = -LTTCOMM_NOT_IMPLEMENTED;
3166 goto error;
3167 }
3168
3169 ret = nb_event;
3170
3171 error:
3172 return ret;
3173 }
3174
3175 /*
3176 * Process the command requested by the lttng client within the command
3177 * context structure. This function make sure that the return structure (llm)
3178 * is set and ready for transmission before returning.
3179 *
3180 * Return any error encountered or 0 for success.
3181 */
3182 static int process_client_msg(struct command_ctx *cmd_ctx)
3183 {
3184 int ret = LTTCOMM_OK;
3185 int need_tracing_session = 1;
3186
3187 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3188
3189 /*
3190 * Check for command that don't needs to allocate a returned payload. We do
3191 * this here so we don't have to make the call for no payload at each
3192 * command.
3193 */
3194 switch(cmd_ctx->lsm->cmd_type) {
3195 case LTTNG_LIST_SESSIONS:
3196 case LTTNG_LIST_TRACEPOINTS:
3197 case LTTNG_LIST_DOMAINS:
3198 case LTTNG_LIST_CHANNELS:
3199 case LTTNG_LIST_EVENTS:
3200 break;
3201 default:
3202 /* Setup lttng message with no payload */
3203 ret = setup_lttng_msg(cmd_ctx, 0);
3204 if (ret < 0) {
3205 /* This label does not try to unlock the session */
3206 goto init_setup_error;
3207 }
3208 }
3209
3210 /* Commands that DO NOT need a session. */
3211 switch (cmd_ctx->lsm->cmd_type) {
3212 case LTTNG_CALIBRATE:
3213 case LTTNG_CREATE_SESSION:
3214 case LTTNG_LIST_SESSIONS:
3215 case LTTNG_LIST_TRACEPOINTS:
3216 need_tracing_session = 0;
3217 break;
3218 default:
3219 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3220 session_lock_list();
3221 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3222 session_unlock_list();
3223 if (cmd_ctx->session == NULL) {
3224 if (cmd_ctx->lsm->session.name != NULL) {
3225 ret = LTTCOMM_SESS_NOT_FOUND;
3226 } else {
3227 /* If no session name specified */
3228 ret = LTTCOMM_SELECT_SESS;
3229 }
3230 goto error;
3231 } else {
3232 /* Acquire lock for the session */
3233 session_lock(cmd_ctx->session);
3234 }
3235 break;
3236 }
3237
3238 /*
3239 * Check domain type for specific "pre-action".
3240 */
3241 switch (cmd_ctx->lsm->domain.type) {
3242 case LTTNG_DOMAIN_KERNEL:
3243 /* Kernel tracer check */
3244 if (kernel_tracer_fd == 0) {
3245 /* Basically, load kernel tracer modules */
3246 init_kernel_tracer();
3247 if (kernel_tracer_fd == 0) {
3248 ret = LTTCOMM_KERN_NA;
3249 goto error;
3250 }
3251 }
3252
3253 /* Need a session for kernel command */
3254 if (need_tracing_session) {
3255 if (cmd_ctx->session->kernel_session == NULL) {
3256 ret = create_kernel_session(cmd_ctx->session);
3257 if (ret < 0) {
3258 ret = LTTCOMM_KERN_SESS_FAIL;
3259 goto error;
3260 }
3261 }
3262
3263 /* Start the kernel consumer daemon */
3264 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3265 if (kconsumer_data.pid == 0 &&
3266 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3267 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3268 ret = start_consumerd(&kconsumer_data);
3269 if (ret < 0) {
3270 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3271 goto error;
3272 }
3273 } else {
3274 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3275 }
3276 }
3277 break;
3278 case LTTNG_DOMAIN_UST:
3279 {
3280 if (need_tracing_session) {
3281 if (cmd_ctx->session->ust_session == NULL) {
3282 ret = create_ust_session(cmd_ctx->session,
3283 &cmd_ctx->lsm->domain);
3284 if (ret != LTTCOMM_OK) {
3285 goto error;
3286 }
3287 }
3288 /* Start the UST consumer daemons */
3289 /* 64-bit */
3290 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3291 if (consumerd64_bin[0] != '\0' &&
3292 ustconsumer64_data.pid == 0 &&
3293 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3294 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3295 ret = start_consumerd(&ustconsumer64_data);
3296 if (ret < 0) {
3297 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3298 ust_consumerd64_fd = -EINVAL;
3299 goto error;
3300 }
3301
3302 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3303 } else {
3304 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3305 }
3306 /* 32-bit */
3307 if (consumerd32_bin[0] != '\0' &&
3308 ustconsumer32_data.pid == 0 &&
3309 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3310 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3311 ret = start_consumerd(&ustconsumer32_data);
3312 if (ret < 0) {
3313 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3314 ust_consumerd32_fd = -EINVAL;
3315 goto error;
3316 }
3317 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3318 } else {
3319 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3320 }
3321 }
3322 break;
3323 }
3324 default:
3325 break;
3326 }
3327
3328 /* Process by command type */
3329 switch (cmd_ctx->lsm->cmd_type) {
3330 case LTTNG_ADD_CONTEXT:
3331 {
3332 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3333 cmd_ctx->lsm->u.context.channel_name,
3334 cmd_ctx->lsm->u.context.event_name,
3335 &cmd_ctx->lsm->u.context.ctx);
3336 break;
3337 }
3338 case LTTNG_DISABLE_CHANNEL:
3339 {
3340 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3341 cmd_ctx->lsm->u.disable.channel_name);
3342 break;
3343 }