Merge branch 'master' of git://git.lttng.org/lttng-tools
[lttng-tools.git] / src / bin / lttng-sessiond / main.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the Free
7 * Software Foundation; only version 2 of the License.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
16 * Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18
19 #define _GNU_SOURCE
20 #include <getopt.h>
21 #include <grp.h>
22 #include <limits.h>
23 #include <pthread.h>
24 #include <semaphore.h>
25 #include <signal.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <sys/mman.h>
30 #include <sys/mount.h>
31 #include <sys/resource.h>
32 #include <sys/socket.h>
33 #include <sys/stat.h>
34 #include <sys/types.h>
35 #include <sys/wait.h>
36 #include <urcu/futex.h>
37 #include <unistd.h>
38 #include <config.h>
39
40 #include <common/common.h>
41 #include <common/compat/poll.h>
42 #include <common/compat/socket.h>
43 #include <common/defaults.h>
44 #include <common/kernel-consumer/kernel-consumer.h>
45 #include <common/ust-consumer/ust-consumer.h>
46
47 #include "lttng-sessiond.h"
48 #include "channel.h"
49 #include "context.h"
50 #include "event.h"
51 #include "futex.h"
52 #include "kernel.h"
53 #include "modprobe.h"
54 #include "shm.h"
55 #include "ust-ctl.h"
56 #include "utils.h"
57
58 #define CONSUMERD_FILE "lttng-consumerd"
59
60 struct consumer_data {
61 enum lttng_consumer_type type;
62
63 pthread_t thread; /* Worker thread interacting with the consumer */
64 sem_t sem;
65
66 /* Mutex to control consumerd pid assignation */
67 pthread_mutex_t pid_mutex;
68 pid_t pid;
69
70 int err_sock;
71 int cmd_sock;
72
73 /* consumer error and command Unix socket path */
74 char err_unix_sock_path[PATH_MAX];
75 char cmd_unix_sock_path[PATH_MAX];
76 };
77
78 /* Const values */
79 const char default_home_dir[] = DEFAULT_HOME_DIR;
80 const char default_tracing_group[] = DEFAULT_TRACING_GROUP;
81 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
82 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
83
84 /* Variables */
85 int opt_verbose; /* Not static for lttngerr.h */
86 int opt_verbose_consumer; /* Not static for lttngerr.h */
87 int opt_quiet; /* Not static for lttngerr.h */
88
89 const char *progname;
90 const char *opt_tracing_group;
91 static int opt_sig_parent;
92 static int opt_daemon;
93 static int opt_no_kernel;
94 static int is_root; /* Set to 1 if the daemon is running as root */
95 static pid_t ppid; /* Parent PID for --sig-parent option */
96 static char *rundir;
97
98 /* Consumer daemon specific control data */
99 static struct consumer_data kconsumer_data = {
100 .type = LTTNG_CONSUMER_KERNEL,
101 .err_unix_sock_path = DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
102 .cmd_unix_sock_path = DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
103 };
104 static struct consumer_data ustconsumer64_data = {
105 .type = LTTNG_CONSUMER64_UST,
106 .err_unix_sock_path = DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
107 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
108 };
109 static struct consumer_data ustconsumer32_data = {
110 .type = LTTNG_CONSUMER32_UST,
111 .err_unix_sock_path = DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
112 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
113 };
114
115 static int dispatch_thread_exit;
116
117 /* Global application Unix socket path */
118 static char apps_unix_sock_path[PATH_MAX];
119 /* Global client Unix socket path */
120 static char client_unix_sock_path[PATH_MAX];
121 /* global wait shm path for UST */
122 static char wait_shm_path[PATH_MAX];
123
124 /* Sockets and FDs */
125 static int client_sock = -1;
126 static int apps_sock = -1;
127 static int kernel_tracer_fd = -1;
128 static int kernel_poll_pipe[2] = { -1, -1 };
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] = { -1, -1 };
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] = { -1, -1 };
141
142 /* Pthread, Mutexes and Semaphores */
143 static pthread_t apps_thread;
144 static pthread_t reg_apps_thread;
145 static pthread_t client_thread;
146 static pthread_t kernel_thread;
147 static pthread_t dispatch_thread;
148
149
150 /*
151 * UST registration command queue. This queue is tied with a futex and uses a N
152 * wakers / 1 waiter implemented and detailed in futex.c/.h
153 *
154 * The thread_manage_apps and thread_dispatch_ust_registration interact with
155 * this queue and the wait/wake scheme.
156 */
157 static struct ust_cmd_queue ust_cmd_queue;
158
159 /*
160 * Pointer initialized before thread creation.
161 *
162 * This points to the tracing session list containing the session count and a
163 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
164 * MUST NOT be taken if you call a public function in session.c.
165 *
166 * The lock is nested inside the structure: session_list_ptr->lock. Please use
167 * session_lock_list and session_unlock_list for lock acquisition.
168 */
169 static struct ltt_session_list *session_list_ptr;
170
171 int ust_consumerd64_fd = -1;
172 int ust_consumerd32_fd = -1;
173
174 static const char *consumerd32_bin = CONFIG_CONSUMERD32_BIN;
175 static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
176 static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
177 static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
178
179 static
180 void setup_consumerd_path(void)
181 {
182 const char *bin, *libdir;
183
184 /*
185 * Allow INSTALL_BIN_PATH to be used as a target path for the
186 * native architecture size consumer if CONFIG_CONSUMER*_PATH
187 * has not been defined.
188 */
189 #if (CAA_BITS_PER_LONG == 32)
190 if (!consumerd32_bin[0]) {
191 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
192 }
193 if (!consumerd32_libdir[0]) {
194 consumerd32_libdir = INSTALL_LIB_PATH;
195 }
196 #elif (CAA_BITS_PER_LONG == 64)
197 if (!consumerd64_bin[0]) {
198 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
199 }
200 if (!consumerd64_libdir[0]) {
201 consumerd64_libdir = INSTALL_LIB_PATH;
202 }
203 #else
204 #error "Unknown bitness"
205 #endif
206
207 /*
208 * runtime env. var. overrides the build default.
209 */
210 bin = getenv("LTTNG_CONSUMERD32_BIN");
211 if (bin) {
212 consumerd32_bin = bin;
213 }
214 bin = getenv("LTTNG_CONSUMERD64_BIN");
215 if (bin) {
216 consumerd64_bin = bin;
217 }
218 libdir = getenv("LTTNG_CONSUMERD32_LIBDIR");
219 if (libdir) {
220 consumerd32_libdir = libdir;
221 }
222 libdir = getenv("LTTNG_CONSUMERD64_LIBDIR");
223 if (libdir) {
224 consumerd64_libdir = libdir;
225 }
226 }
227
228 /*
229 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
230 */
231 static int create_thread_poll_set(struct lttng_poll_event *events,
232 unsigned int size)
233 {
234 int ret;
235
236 if (events == NULL || size == 0) {
237 ret = -1;
238 goto error;
239 }
240
241 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
242 if (ret < 0) {
243 goto error;
244 }
245
246 /* Add quit pipe */
247 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
248 if (ret < 0) {
249 goto error;
250 }
251
252 return 0;
253
254 error:
255 return ret;
256 }
257
258 /*
259 * Check if the thread quit pipe was triggered.
260 *
261 * Return 1 if it was triggered else 0;
262 */
263 static int check_thread_quit_pipe(int fd, uint32_t events)
264 {
265 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
266 return 1;
267 }
268
269 return 0;
270 }
271
272 /*
273 * Return group ID of the tracing group or -1 if not found.
274 */
275 static gid_t allowed_group(void)
276 {
277 struct group *grp;
278
279 if (opt_tracing_group) {
280 grp = getgrnam(opt_tracing_group);
281 } else {
282 grp = getgrnam(default_tracing_group);
283 }
284 if (!grp) {
285 return -1;
286 } else {
287 return grp->gr_gid;
288 }
289 }
290
291 /*
292 * Init thread quit pipe.
293 *
294 * Return -1 on error or 0 if all pipes are created.
295 */
296 static int init_thread_quit_pipe(void)
297 {
298 int ret, i;
299
300 ret = pipe(thread_quit_pipe);
301 if (ret < 0) {
302 PERROR("thread quit pipe");
303 goto error;
304 }
305
306 for (i = 0; i < 2; i++) {
307 ret = fcntl(thread_quit_pipe[i], F_SETFD, FD_CLOEXEC);
308 if (ret < 0) {
309 PERROR("fcntl");
310 goto error;
311 }
312 }
313
314 error:
315 return ret;
316 }
317
318 /*
319 * Complete teardown of a kernel session. This free all data structure related
320 * to a kernel session and update counter.
321 */
322 static void teardown_kernel_session(struct ltt_session *session)
323 {
324 if (!session->kernel_session) {
325 DBG3("No kernel session when tearing down session");
326 return;
327 }
328
329 DBG("Tearing down kernel session");
330
331 /*
332 * If a custom kernel consumer was registered, close the socket before
333 * tearing down the complete kernel session structure
334 */
335 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
336 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
337 }
338
339 trace_kernel_destroy_session(session->kernel_session);
340 }
341
342 /*
343 * Complete teardown of all UST sessions. This will free everything on his path
344 * and destroy the core essence of all ust sessions :)
345 */
346 static void teardown_ust_session(struct ltt_session *session)
347 {
348 int ret;
349
350 if (!session->ust_session) {
351 DBG3("No UST session when tearing down session");
352 return;
353 }
354
355 DBG("Tearing down UST session(s)");
356
357 ret = ust_app_destroy_trace_all(session->ust_session);
358 if (ret) {
359 ERR("Error in ust_app_destroy_trace_all");
360 }
361
362 trace_ust_destroy_session(session->ust_session);
363 }
364
365 /*
366 * Stop all threads by closing the thread quit pipe.
367 */
368 static void stop_threads(void)
369 {
370 int ret;
371
372 /* Stopping all threads */
373 DBG("Terminating all threads");
374 ret = notify_thread_pipe(thread_quit_pipe[1]);
375 if (ret < 0) {
376 ERR("write error on thread quit pipe");
377 }
378
379 /* Dispatch thread */
380 dispatch_thread_exit = 1;
381 futex_nto1_wake(&ust_cmd_queue.futex);
382 }
383
384 /*
385 * Cleanup the daemon
386 */
387 static void cleanup(void)
388 {
389 int ret, i;
390 char *cmd;
391 struct ltt_session *sess, *stmp;
392
393 DBG("Cleaning up");
394
395 DBG("Removing %s directory", rundir);
396 ret = asprintf(&cmd, "rm -rf %s", rundir);
397 if (ret < 0) {
398 ERR("asprintf failed. Something is really wrong!");
399 }
400
401 /* Remove lttng run directory */
402 ret = system(cmd);
403 if (ret < 0) {
404 ERR("Unable to clean %s", rundir);
405 }
406 free(cmd);
407
408 DBG("Cleaning up all sessions");
409
410 /* Destroy session list mutex */
411 if (session_list_ptr != NULL) {
412 pthread_mutex_destroy(&session_list_ptr->lock);
413
414 /* Cleanup ALL session */
415 cds_list_for_each_entry_safe(sess, stmp,
416 &session_list_ptr->head, list) {
417 teardown_kernel_session(sess);
418 teardown_ust_session(sess);
419 free(sess);
420 }
421 }
422
423 DBG("Closing all UST sockets");
424 ust_app_clean_list();
425
426 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
427
428 if (is_root && !opt_no_kernel) {
429 DBG2("Closing kernel fd");
430 if (kernel_tracer_fd >= 0) {
431 ret = close(kernel_tracer_fd);
432 if (ret) {
433 PERROR("close");
434 }
435 }
436 DBG("Unloading kernel modules");
437 modprobe_remove_lttng_all();
438 }
439
440 /*
441 * Closing all pipes used for communication between threads.
442 */
443 for (i = 0; i < 2; i++) {
444 if (kernel_poll_pipe[i] >= 0) {
445 ret = close(kernel_poll_pipe[i]);
446 if (ret) {
447 PERROR("close");
448 }
449
450 }
451 }
452 for (i = 0; i < 2; i++) {
453 if (thread_quit_pipe[i] >= 0) {
454 ret = close(thread_quit_pipe[i]);
455 if (ret) {
456 PERROR("close");
457 }
458 }
459 }
460 for (i = 0; i < 2; i++) {
461 if (apps_cmd_pipe[i] >= 0) {
462 ret = close(apps_cmd_pipe[i]);
463 if (ret) {
464 PERROR("close");
465 }
466 }
467 }
468
469 /* <fun> */
470 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
471 "Matthew, BEET driven development works!%c[%dm",
472 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
473 /* </fun> */
474 }
475
476 /*
477 * Send data on a unix socket using the liblttsessiondcomm API.
478 *
479 * Return lttcomm error code.
480 */
481 static int send_unix_sock(int sock, void *buf, size_t len)
482 {
483 /* Check valid length */
484 if (len <= 0) {
485 return -1;
486 }
487
488 return lttcomm_send_unix_sock(sock, buf, len);
489 }
490
491 /*
492 * Free memory of a command context structure.
493 */
494 static void clean_command_ctx(struct command_ctx **cmd_ctx)
495 {
496 DBG("Clean command context structure");
497 if (*cmd_ctx) {
498 if ((*cmd_ctx)->llm) {
499 free((*cmd_ctx)->llm);
500 }
501 if ((*cmd_ctx)->lsm) {
502 free((*cmd_ctx)->lsm);
503 }
504 free(*cmd_ctx);
505 *cmd_ctx = NULL;
506 }
507 }
508
509 /*
510 * Send all stream fds of kernel channel to the consumer.
511 */
512 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
513 int sock, struct ltt_kernel_channel *channel,
514 uid_t uid, gid_t gid)
515 {
516 int ret;
517 struct ltt_kernel_stream *stream;
518 struct lttcomm_consumer_msg lkm;
519
520 DBG("Sending streams of channel %s to kernel consumer",
521 channel->channel->name);
522
523 /* Send channel */
524 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
525 lkm.u.channel.channel_key = channel->fd;
526 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
527 lkm.u.channel.mmap_len = 0; /* for kernel */
528 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
529 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
530 if (ret < 0) {
531 PERROR("send consumer channel");
532 goto error;
533 }
534
535 /* Send streams */
536 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
537 if (!stream->fd) {
538 continue;
539 }
540 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
541 lkm.u.stream.channel_key = channel->fd;
542 lkm.u.stream.stream_key = stream->fd;
543 lkm.u.stream.state = stream->state;
544 lkm.u.stream.output = channel->channel->attr.output;
545 lkm.u.stream.mmap_len = 0; /* for kernel */
546 lkm.u.stream.uid = uid;
547 lkm.u.stream.gid = gid;
548 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
549 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
550 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
551 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
552 if (ret < 0) {
553 PERROR("send consumer stream");
554 goto error;
555 }
556 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
557 if (ret < 0) {
558 PERROR("send consumer stream ancillary data");
559 goto error;
560 }
561 }
562
563 DBG("consumer channel streams sent");
564
565 return 0;
566
567 error:
568 return ret;
569 }
570
571 /*
572 * Send all stream fds of the kernel session to the consumer.
573 */
574 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
575 struct ltt_kernel_session *session)
576 {
577 int ret;
578 struct ltt_kernel_channel *chan;
579 struct lttcomm_consumer_msg lkm;
580 int sock = session->consumer_fd;
581
582 DBG("Sending metadata stream fd");
583
584 /* Extra protection. It's NOT supposed to be set to 0 at this point */
585 if (session->consumer_fd == 0) {
586 session->consumer_fd = consumer_data->cmd_sock;
587 }
588
589 if (session->metadata_stream_fd != 0) {
590 /* Send metadata channel fd */
591 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
592 lkm.u.channel.channel_key = session->metadata->fd;
593 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
594 lkm.u.channel.mmap_len = 0; /* for kernel */
595 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
596 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
597 if (ret < 0) {
598 PERROR("send consumer channel");
599 goto error;
600 }
601
602 /* Send metadata stream fd */
603 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
604 lkm.u.stream.channel_key = session->metadata->fd;
605 lkm.u.stream.stream_key = session->metadata_stream_fd;
606 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
607 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
608 lkm.u.stream.mmap_len = 0; /* for kernel */
609 lkm.u.stream.uid = session->uid;
610 lkm.u.stream.gid = session->gid;
611 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
612 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
613 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
614 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
615 if (ret < 0) {
616 PERROR("send consumer stream");
617 goto error;
618 }
619 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
620 if (ret < 0) {
621 PERROR("send consumer stream");
622 goto error;
623 }
624 }
625
626 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
627 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
628 session->uid, session->gid);
629 if (ret < 0) {
630 goto error;
631 }
632 }
633
634 DBG("consumer fds (metadata and channel streams) sent");
635
636 return 0;
637
638 error:
639 return ret;
640 }
641
642 /*
643 * Notify UST applications using the shm mmap futex.
644 */
645 static int notify_ust_apps(int active)
646 {
647 char *wait_shm_mmap;
648
649 DBG("Notifying applications of session daemon state: %d", active);
650
651 /* See shm.c for this call implying mmap, shm and futex calls */
652 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
653 if (wait_shm_mmap == NULL) {
654 goto error;
655 }
656
657 /* Wake waiting process */
658 futex_wait_update((int32_t *) wait_shm_mmap, active);
659
660 /* Apps notified successfully */
661 return 0;
662
663 error:
664 return -1;
665 }
666
667 /*
668 * Setup the outgoing data buffer for the response (llm) by allocating the
669 * right amount of memory and copying the original information from the lsm
670 * structure.
671 *
672 * Return total size of the buffer pointed by buf.
673 */
674 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
675 {
676 int ret, buf_size;
677
678 buf_size = size;
679
680 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
681 if (cmd_ctx->llm == NULL) {
682 PERROR("zmalloc");
683 ret = -ENOMEM;
684 goto error;
685 }
686
687 /* Copy common data */
688 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
689 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
690
691 cmd_ctx->llm->data_size = size;
692 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
693
694 return buf_size;
695
696 error:
697 return ret;
698 }
699
700 /*
701 * Update the kernel poll set of all channel fd available over all tracing
702 * session. Add the wakeup pipe at the end of the set.
703 */
704 static int update_kernel_poll(struct lttng_poll_event *events)
705 {
706 int ret;
707 struct ltt_session *session;
708 struct ltt_kernel_channel *channel;
709
710 DBG("Updating kernel poll set");
711
712 session_lock_list();
713 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
714 session_lock(session);
715 if (session->kernel_session == NULL) {
716 session_unlock(session);
717 continue;
718 }
719
720 cds_list_for_each_entry(channel,
721 &session->kernel_session->channel_list.head, list) {
722 /* Add channel fd to the kernel poll set */
723 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
724 if (ret < 0) {
725 session_unlock(session);
726 goto error;
727 }
728 DBG("Channel fd %d added to kernel set", channel->fd);
729 }
730 session_unlock(session);
731 }
732 session_unlock_list();
733
734 return 0;
735
736 error:
737 session_unlock_list();
738 return -1;
739 }
740
741 /*
742 * Find the channel fd from 'fd' over all tracing session. When found, check
743 * for new channel stream and send those stream fds to the kernel consumer.
744 *
745 * Useful for CPU hotplug feature.
746 */
747 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
748 {
749 int ret = 0;
750 struct ltt_session *session;
751 struct ltt_kernel_channel *channel;
752
753 DBG("Updating kernel streams for channel fd %d", fd);
754
755 session_lock_list();
756 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
757 session_lock(session);
758 if (session->kernel_session == NULL) {
759 session_unlock(session);
760 continue;
761 }
762
763 /* This is not suppose to be 0 but this is an extra security check */
764 if (session->kernel_session->consumer_fd == 0) {
765 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
766 }
767
768 cds_list_for_each_entry(channel,
769 &session->kernel_session->channel_list.head, list) {
770 if (channel->fd == fd) {
771 DBG("Channel found, updating kernel streams");
772 ret = kernel_open_channel_stream(channel);
773 if (ret < 0) {
774 goto error;
775 }
776
777 /*
778 * Have we already sent fds to the consumer? If yes, it means
779 * that tracing is started so it is safe to send our updated
780 * stream fds.
781 */
782 if (session->kernel_session->consumer_fds_sent == 1) {
783 ret = send_kconsumer_channel_streams(consumer_data,
784 session->kernel_session->consumer_fd, channel,
785 session->uid, session->gid);
786 if (ret < 0) {
787 goto error;
788 }
789 }
790 goto error;
791 }
792 }
793 session_unlock(session);
794 }
795 session_unlock_list();
796 return ret;
797
798 error:
799 session_unlock(session);
800 session_unlock_list();
801 return ret;
802 }
803
804 /*
805 * For each tracing session, update newly registered apps.
806 */
807 static void update_ust_app(int app_sock)
808 {
809 struct ltt_session *sess, *stmp;
810
811 session_lock_list();
812
813 /* For all tracing session(s) */
814 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
815 session_lock(sess);
816 if (sess->ust_session) {
817 ust_app_global_update(sess->ust_session, app_sock);
818 }
819 session_unlock(sess);
820 }
821
822 session_unlock_list();
823 }
824
825 /*
826 * This thread manage event coming from the kernel.
827 *
828 * Features supported in this thread:
829 * -) CPU Hotplug
830 */
831 static void *thread_manage_kernel(void *data)
832 {
833 int ret, i, pollfd, update_poll_flag = 1;
834 uint32_t revents, nb_fd;
835 char tmp;
836 struct lttng_poll_event events;
837
838 DBG("Thread manage kernel started");
839
840 ret = create_thread_poll_set(&events, 2);
841 if (ret < 0) {
842 goto error_poll_create;
843 }
844
845 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
846 if (ret < 0) {
847 goto error;
848 }
849
850 while (1) {
851 if (update_poll_flag == 1) {
852 /*
853 * Reset number of fd in the poll set. Always 2 since there is the thread
854 * quit pipe and the kernel pipe.
855 */
856 events.nb_fd = 2;
857
858 ret = update_kernel_poll(&events);
859 if (ret < 0) {
860 goto error;
861 }
862 update_poll_flag = 0;
863 }
864
865 nb_fd = LTTNG_POLL_GETNB(&events);
866
867 DBG("Thread kernel polling on %d fds", nb_fd);
868
869 /* Zeroed the poll events */
870 lttng_poll_reset(&events);
871
872 /* Poll infinite value of time */
873 restart:
874 ret = lttng_poll_wait(&events, -1);
875 if (ret < 0) {
876 /*
877 * Restart interrupted system call.
878 */
879 if (errno == EINTR) {
880 goto restart;
881 }
882 goto error;
883 } else if (ret == 0) {
884 /* Should not happen since timeout is infinite */
885 ERR("Return value of poll is 0 with an infinite timeout.\n"
886 "This should not have happened! Continuing...");
887 continue;
888 }
889
890 for (i = 0; i < nb_fd; i++) {
891 /* Fetch once the poll data */
892 revents = LTTNG_POLL_GETEV(&events, i);
893 pollfd = LTTNG_POLL_GETFD(&events, i);
894
895 /* Thread quit pipe has been closed. Killing thread. */
896 ret = check_thread_quit_pipe(pollfd, revents);
897 if (ret) {
898 goto error;
899 }
900
901 /* Check for data on kernel pipe */
902 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
903 ret = read(kernel_poll_pipe[0], &tmp, 1);
904 update_poll_flag = 1;
905 continue;
906 } else {
907 /*
908 * New CPU detected by the kernel. Adding kernel stream to
909 * kernel session and updating the kernel consumer
910 */
911 if (revents & LPOLLIN) {
912 ret = update_kernel_stream(&kconsumer_data, pollfd);
913 if (ret < 0) {
914 continue;
915 }
916 break;
917 /*
918 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
919 * and unregister kernel stream at this point.
920 */
921 }
922 }
923 }
924 }
925
926 error:
927 lttng_poll_clean(&events);
928 error_poll_create:
929 DBG("Kernel thread dying");
930 return NULL;
931 }
932
933 /*
934 * This thread manage the consumer error sent back to the session daemon.
935 */
936 static void *thread_manage_consumer(void *data)
937 {
938 int sock = -1, i, ret, pollfd;
939 uint32_t revents, nb_fd;
940 enum lttcomm_return_code code;
941 struct lttng_poll_event events;
942 struct consumer_data *consumer_data = data;
943
944 DBG("[thread] Manage consumer started");
945
946 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
947 if (ret < 0) {
948 goto error_listen;
949 }
950
951 /*
952 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
953 * Nothing more will be added to this poll set.
954 */
955 ret = create_thread_poll_set(&events, 2);
956 if (ret < 0) {
957 goto error_poll;
958 }
959
960 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
961 if (ret < 0) {
962 goto error;
963 }
964
965 nb_fd = LTTNG_POLL_GETNB(&events);
966
967 /* Inifinite blocking call, waiting for transmission */
968 restart:
969 ret = lttng_poll_wait(&events, -1);
970 if (ret < 0) {
971 /*
972 * Restart interrupted system call.
973 */
974 if (errno == EINTR) {
975 goto restart;
976 }
977 goto error;
978 }
979
980 for (i = 0; i < nb_fd; i++) {
981 /* Fetch once the poll data */
982 revents = LTTNG_POLL_GETEV(&events, i);
983 pollfd = LTTNG_POLL_GETFD(&events, i);
984
985 /* Thread quit pipe has been closed. Killing thread. */
986 ret = check_thread_quit_pipe(pollfd, revents);
987 if (ret) {
988 goto error;
989 }
990
991 /* Event on the registration socket */
992 if (pollfd == consumer_data->err_sock) {
993 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
994 ERR("consumer err socket poll error");
995 goto error;
996 }
997 }
998 }
999
1000 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
1001 if (sock < 0) {
1002 goto error;
1003 }
1004
1005 DBG2("Receiving code from consumer err_sock");
1006
1007 /* Getting status code from kconsumerd */
1008 ret = lttcomm_recv_unix_sock(sock, &code,
1009 sizeof(enum lttcomm_return_code));
1010 if (ret <= 0) {
1011 goto error;
1012 }
1013
1014 if (code == CONSUMERD_COMMAND_SOCK_READY) {
1015 consumer_data->cmd_sock =
1016 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
1017 if (consumer_data->cmd_sock < 0) {
1018 sem_post(&consumer_data->sem);
1019 PERROR("consumer connect");
1020 goto error;
1021 }
1022 /* Signal condition to tell that the kconsumerd is ready */
1023 sem_post(&consumer_data->sem);
1024 DBG("consumer command socket ready");
1025 } else {
1026 ERR("consumer error when waiting for SOCK_READY : %s",
1027 lttcomm_get_readable_code(-code));
1028 goto error;
1029 }
1030
1031 /* Remove the kconsumerd error sock since we've established a connexion */
1032 ret = lttng_poll_del(&events, consumer_data->err_sock);
1033 if (ret < 0) {
1034 goto error;
1035 }
1036
1037 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1038 if (ret < 0) {
1039 goto error;
1040 }
1041
1042 /* Update number of fd */
1043 nb_fd = LTTNG_POLL_GETNB(&events);
1044
1045 /* Inifinite blocking call, waiting for transmission */
1046 restart_poll:
1047 ret = lttng_poll_wait(&events, -1);
1048 if (ret < 0) {
1049 /*
1050 * Restart interrupted system call.
1051 */
1052 if (errno == EINTR) {
1053 goto restart_poll;
1054 }
1055 goto error;
1056 }
1057
1058 for (i = 0; i < nb_fd; i++) {
1059 /* Fetch once the poll data */
1060 revents = LTTNG_POLL_GETEV(&events, i);
1061 pollfd = LTTNG_POLL_GETFD(&events, i);
1062
1063 /* Thread quit pipe has been closed. Killing thread. */
1064 ret = check_thread_quit_pipe(pollfd, revents);
1065 if (ret) {
1066 goto error;
1067 }
1068
1069 /* Event on the kconsumerd socket */
1070 if (pollfd == sock) {
1071 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1072 ERR("consumer err socket second poll error");
1073 goto error;
1074 }
1075 }
1076 }
1077
1078 /* Wait for any kconsumerd error */
1079 ret = lttcomm_recv_unix_sock(sock, &code,
1080 sizeof(enum lttcomm_return_code));
1081 if (ret <= 0) {
1082 ERR("consumer closed the command socket");
1083 goto error;
1084 }
1085
1086 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1087
1088 error:
1089 if (consumer_data->err_sock >= 0) {
1090 ret = close(consumer_data->err_sock);
1091 if (ret) {
1092 PERROR("close");
1093 }
1094 }
1095 if (consumer_data->cmd_sock >= 0) {
1096 ret = close(consumer_data->cmd_sock);
1097 if (ret) {
1098 PERROR("close");
1099 }
1100 }
1101 if (sock >= 0) {
1102 ret = close(sock);
1103 if (ret) {
1104 PERROR("close");
1105 }
1106 }
1107
1108 unlink(consumer_data->err_unix_sock_path);
1109 unlink(consumer_data->cmd_unix_sock_path);
1110 consumer_data->pid = 0;
1111
1112 lttng_poll_clean(&events);
1113 error_poll:
1114 error_listen:
1115 DBG("consumer thread cleanup completed");
1116
1117 return NULL;
1118 }
1119
1120 /*
1121 * This thread manage application communication.
1122 */
1123 static void *thread_manage_apps(void *data)
1124 {
1125 int i, ret, pollfd;
1126 uint32_t revents, nb_fd;
1127 struct ust_command ust_cmd;
1128 struct lttng_poll_event events;
1129
1130 DBG("[thread] Manage application started");
1131
1132 rcu_register_thread();
1133 rcu_thread_online();
1134
1135 ret = create_thread_poll_set(&events, 2);
1136 if (ret < 0) {
1137 goto error_poll_create;
1138 }
1139
1140 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1141 if (ret < 0) {
1142 goto error;
1143 }
1144
1145 while (1) {
1146 /* Zeroed the events structure */
1147 lttng_poll_reset(&events);
1148
1149 nb_fd = LTTNG_POLL_GETNB(&events);
1150
1151 DBG("Apps thread polling on %d fds", nb_fd);
1152
1153 /* Inifinite blocking call, waiting for transmission */
1154 restart:
1155 ret = lttng_poll_wait(&events, -1);
1156 if (ret < 0) {
1157 /*
1158 * Restart interrupted system call.
1159 */
1160 if (errno == EINTR) {
1161 goto restart;
1162 }
1163 goto error;
1164 }
1165
1166 for (i = 0; i < nb_fd; i++) {
1167 /* Fetch once the poll data */
1168 revents = LTTNG_POLL_GETEV(&events, i);
1169 pollfd = LTTNG_POLL_GETFD(&events, i);
1170
1171 /* Thread quit pipe has been closed. Killing thread. */
1172 ret = check_thread_quit_pipe(pollfd, revents);
1173 if (ret) {
1174 goto error;
1175 }
1176
1177 /* Inspect the apps cmd pipe */
1178 if (pollfd == apps_cmd_pipe[0]) {
1179 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1180 ERR("Apps command pipe error");
1181 goto error;
1182 } else if (revents & LPOLLIN) {
1183 /* Empty pipe */
1184 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1185 if (ret < 0 || ret < sizeof(ust_cmd)) {
1186 PERROR("read apps cmd pipe");
1187 goto error;
1188 }
1189
1190 /* Register applicaton to the session daemon */
1191 ret = ust_app_register(&ust_cmd.reg_msg,
1192 ust_cmd.sock);
1193 if (ret == -ENOMEM) {
1194 goto error;
1195 } else if (ret < 0) {
1196 break;
1197 }
1198
1199 /*
1200 * Validate UST version compatibility.
1201 */
1202 ret = ust_app_validate_version(ust_cmd.sock);
1203 if (ret >= 0) {
1204 /*
1205 * Add channel(s) and event(s) to newly registered apps
1206 * from lttng global UST domain.
1207 */
1208 update_ust_app(ust_cmd.sock);
1209 }
1210
1211 ret = ust_app_register_done(ust_cmd.sock);
1212 if (ret < 0) {
1213 /*
1214 * If the registration is not possible, we simply
1215 * unregister the apps and continue
1216 */
1217 ust_app_unregister(ust_cmd.sock);
1218 } else {
1219 /*
1220 * We just need here to monitor the close of the UST
1221 * socket and poll set monitor those by default.
1222 * Listen on POLLIN (even if we never expect any
1223 * data) to ensure that hangup wakes us.
1224 */
1225 ret = lttng_poll_add(&events, ust_cmd.sock, LPOLLIN);
1226 if (ret < 0) {
1227 goto error;
1228 }
1229
1230 DBG("Apps with sock %d added to poll set",
1231 ust_cmd.sock);
1232 }
1233
1234 break;
1235 }
1236 } else {
1237 /*
1238 * At this point, we know that a registered application made
1239 * the event at poll_wait.
1240 */
1241 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1242 /* Removing from the poll set */
1243 ret = lttng_poll_del(&events, pollfd);
1244 if (ret < 0) {
1245 goto error;
1246 }
1247
1248 /* Socket closed on remote end. */
1249 ust_app_unregister(pollfd);
1250 break;
1251 }
1252 }
1253 }
1254 }
1255
1256 error:
1257 lttng_poll_clean(&events);
1258 error_poll_create:
1259 DBG("Application communication apps thread cleanup complete");
1260 rcu_thread_offline();
1261 rcu_unregister_thread();
1262 return NULL;
1263 }
1264
1265 /*
1266 * Dispatch request from the registration threads to the application
1267 * communication thread.
1268 */
1269 static void *thread_dispatch_ust_registration(void *data)
1270 {
1271 int ret;
1272 struct cds_wfq_node *node;
1273 struct ust_command *ust_cmd = NULL;
1274
1275 DBG("[thread] Dispatch UST command started");
1276
1277 while (!dispatch_thread_exit) {
1278 /* Atomically prepare the queue futex */
1279 futex_nto1_prepare(&ust_cmd_queue.futex);
1280
1281 do {
1282 /* Dequeue command for registration */
1283 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1284 if (node == NULL) {
1285 DBG("Woken up but nothing in the UST command queue");
1286 /* Continue thread execution */
1287 break;
1288 }
1289
1290 ust_cmd = caa_container_of(node, struct ust_command, node);
1291
1292 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1293 " gid:%d sock:%d name:%s (version %d.%d)",
1294 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1295 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1296 ust_cmd->sock, ust_cmd->reg_msg.name,
1297 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1298 /*
1299 * Inform apps thread of the new application registration. This
1300 * call is blocking so we can be assured that the data will be read
1301 * at some point in time or wait to the end of the world :)
1302 */
1303 ret = write(apps_cmd_pipe[1], ust_cmd,
1304 sizeof(struct ust_command));
1305 if (ret < 0) {
1306 PERROR("write apps cmd pipe");
1307 if (errno == EBADF) {
1308 /*
1309 * We can't inform the application thread to process
1310 * registration. We will exit or else application
1311 * registration will not occur and tracing will never
1312 * start.
1313 */
1314 goto error;
1315 }
1316 }
1317 free(ust_cmd);
1318 } while (node != NULL);
1319
1320 /* Futex wait on queue. Blocking call on futex() */
1321 futex_nto1_wait(&ust_cmd_queue.futex);
1322 }
1323
1324 error:
1325 DBG("Dispatch thread dying");
1326 return NULL;
1327 }
1328
1329 /*
1330 * This thread manage application registration.
1331 */
1332 static void *thread_registration_apps(void *data)
1333 {
1334 int sock = -1, i, ret, pollfd;
1335 uint32_t revents, nb_fd;
1336 struct lttng_poll_event events;
1337 /*
1338 * Get allocated in this thread, enqueued to a global queue, dequeued and
1339 * freed in the manage apps thread.
1340 */
1341 struct ust_command *ust_cmd = NULL;
1342
1343 DBG("[thread] Manage application registration started");
1344
1345 ret = lttcomm_listen_unix_sock(apps_sock);
1346 if (ret < 0) {
1347 goto error_listen;
1348 }
1349
1350 /*
1351 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1352 * more will be added to this poll set.
1353 */
1354 ret = create_thread_poll_set(&events, 2);
1355 if (ret < 0) {
1356 goto error_create_poll;
1357 }
1358
1359 /* Add the application registration socket */
1360 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1361 if (ret < 0) {
1362 goto error_poll_add;
1363 }
1364
1365 /* Notify all applications to register */
1366 ret = notify_ust_apps(1);
1367 if (ret < 0) {
1368 ERR("Failed to notify applications or create the wait shared memory.\n"
1369 "Execution continues but there might be problem for already\n"
1370 "running applications that wishes to register.");
1371 }
1372
1373 while (1) {
1374 DBG("Accepting application registration");
1375
1376 nb_fd = LTTNG_POLL_GETNB(&events);
1377
1378 /* Inifinite blocking call, waiting for transmission */
1379 restart:
1380 ret = lttng_poll_wait(&events, -1);
1381 if (ret < 0) {
1382 /*
1383 * Restart interrupted system call.
1384 */
1385 if (errno == EINTR) {
1386 goto restart;
1387 }
1388 goto error;
1389 }
1390
1391 for (i = 0; i < nb_fd; i++) {
1392 /* Fetch once the poll data */
1393 revents = LTTNG_POLL_GETEV(&events, i);
1394 pollfd = LTTNG_POLL_GETFD(&events, i);
1395
1396 /* Thread quit pipe has been closed. Killing thread. */
1397 ret = check_thread_quit_pipe(pollfd, revents);
1398 if (ret) {
1399 goto error;
1400 }
1401
1402 /* Event on the registration socket */
1403 if (pollfd == apps_sock) {
1404 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1405 ERR("Register apps socket poll error");
1406 goto error;
1407 } else if (revents & LPOLLIN) {
1408 sock = lttcomm_accept_unix_sock(apps_sock);
1409 if (sock < 0) {
1410 goto error;
1411 }
1412
1413 /* Create UST registration command for enqueuing */
1414 ust_cmd = zmalloc(sizeof(struct ust_command));
1415 if (ust_cmd == NULL) {
1416 PERROR("ust command zmalloc");
1417 goto error;
1418 }
1419
1420 /*
1421 * Using message-based transmissions to ensure we don't
1422 * have to deal with partially received messages.
1423 */
1424 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1425 sizeof(struct ust_register_msg));
1426 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1427 if (ret < 0) {
1428 PERROR("lttcomm_recv_unix_sock register apps");
1429 } else {
1430 ERR("Wrong size received on apps register");
1431 }
1432 free(ust_cmd);
1433 ret = close(sock);
1434 if (ret) {
1435 PERROR("close");
1436 }
1437 sock = -1;
1438 continue;
1439 }
1440
1441 ust_cmd->sock = sock;
1442
1443 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1444 " gid:%d sock:%d name:%s (version %d.%d)",
1445 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1446 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1447 ust_cmd->sock, ust_cmd->reg_msg.name,
1448 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1449
1450 /*
1451 * Lock free enqueue the registration request. The red pill
1452 * has been taken! This apps will be part of the *system*.
1453 */
1454 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1455
1456 /*
1457 * Wake the registration queue futex. Implicit memory
1458 * barrier with the exchange in cds_wfq_enqueue.
1459 */
1460 futex_nto1_wake(&ust_cmd_queue.futex);
1461 }
1462 }
1463 }
1464 }
1465
1466 error:
1467 /* Notify that the registration thread is gone */
1468 notify_ust_apps(0);
1469
1470 if (apps_sock >= 0) {
1471 ret = close(apps_sock);
1472 if (ret) {
1473 PERROR("close");
1474 }
1475 }
1476 if (sock >= 0) {
1477 ret = close(sock);
1478 if (ret) {
1479 PERROR("close");
1480 }
1481 }
1482 unlink(apps_unix_sock_path);
1483
1484 error_poll_add:
1485 lttng_poll_clean(&events);
1486 error_listen:
1487 error_create_poll:
1488 DBG("UST Registration thread cleanup complete");
1489
1490 return NULL;
1491 }
1492
1493 /*
1494 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1495 * exec or it will fails.
1496 */
1497 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1498 {
1499 int ret;
1500 struct timespec timeout;
1501
1502 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1503 timeout.tv_nsec = 0;
1504
1505 /* Setup semaphore */
1506 ret = sem_init(&consumer_data->sem, 0, 0);
1507 if (ret < 0) {
1508 PERROR("sem_init consumer semaphore");
1509 goto error;
1510 }
1511
1512 ret = pthread_create(&consumer_data->thread, NULL,
1513 thread_manage_consumer, consumer_data);
1514 if (ret != 0) {
1515 PERROR("pthread_create consumer");
1516 ret = -1;
1517 goto error;
1518 }
1519
1520 /* Get time for sem_timedwait absolute timeout */
1521 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1522 if (ret < 0) {
1523 PERROR("clock_gettime spawn consumer");
1524 /* Infinite wait for the kconsumerd thread to be ready */
1525 ret = sem_wait(&consumer_data->sem);
1526 } else {
1527 /* Normal timeout if the gettime was successful */
1528 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1529 ret = sem_timedwait(&consumer_data->sem, &timeout);
1530 }
1531
1532 if (ret < 0) {
1533 if (errno == ETIMEDOUT) {
1534 /*
1535 * Call has timed out so we kill the kconsumerd_thread and return
1536 * an error.
1537 */
1538 ERR("The consumer thread was never ready. Killing it");
1539 ret = pthread_cancel(consumer_data->thread);
1540 if (ret < 0) {
1541 PERROR("pthread_cancel consumer thread");
1542 }
1543 } else {
1544 PERROR("semaphore wait failed consumer thread");
1545 }
1546 goto error;
1547 }
1548
1549 pthread_mutex_lock(&consumer_data->pid_mutex);
1550 if (consumer_data->pid == 0) {
1551 ERR("Kconsumerd did not start");
1552 pthread_mutex_unlock(&consumer_data->pid_mutex);
1553 goto error;
1554 }
1555 pthread_mutex_unlock(&consumer_data->pid_mutex);
1556
1557 return 0;
1558
1559 error:
1560 return ret;
1561 }
1562
1563 /*
1564 * Join consumer thread
1565 */
1566 static int join_consumer_thread(struct consumer_data *consumer_data)
1567 {
1568 void *status;
1569 int ret;
1570
1571 if (consumer_data->pid != 0) {
1572 ret = kill(consumer_data->pid, SIGTERM);
1573 if (ret) {
1574 ERR("Error killing consumer daemon");
1575 return ret;
1576 }
1577 return pthread_join(consumer_data->thread, &status);
1578 } else {
1579 return 0;
1580 }
1581 }
1582
1583 /*
1584 * Fork and exec a consumer daemon (consumerd).
1585 *
1586 * Return pid if successful else -1.
1587 */
1588 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1589 {
1590 int ret;
1591 pid_t pid;
1592 const char *consumer_to_use;
1593 const char *verbosity;
1594 struct stat st;
1595
1596 DBG("Spawning consumerd");
1597
1598 pid = fork();
1599 if (pid == 0) {
1600 /*
1601 * Exec consumerd.
1602 */
1603 if (opt_verbose_consumer) {
1604 verbosity = "--verbose";
1605 } else {
1606 verbosity = "--quiet";
1607 }
1608 switch (consumer_data->type) {
1609 case LTTNG_CONSUMER_KERNEL:
1610 /*
1611 * Find out which consumerd to execute. We will first try the
1612 * 64-bit path, then the sessiond's installation directory, and
1613 * fallback on the 32-bit one,
1614 */
1615 DBG3("Looking for a kernel consumer at these locations:");
1616 DBG3(" 1) %s", consumerd64_bin);
1617 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1618 DBG3(" 3) %s", consumerd32_bin);
1619 if (stat(consumerd64_bin, &st) == 0) {
1620 DBG3("Found location #1");
1621 consumer_to_use = consumerd64_bin;
1622 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1623 DBG3("Found location #2");
1624 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1625 } else if (stat(consumerd32_bin, &st) == 0) {
1626 DBG3("Found location #3");
1627 consumer_to_use = consumerd32_bin;
1628 } else {
1629 DBG("Could not find any valid consumerd executable");
1630 break;
1631 }
1632 DBG("Using kernel consumer at: %s", consumer_to_use);
1633 execl(consumer_to_use,
1634 "lttng-consumerd", verbosity, "-k",
1635 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1636 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1637 NULL);
1638 break;
1639 case LTTNG_CONSUMER64_UST:
1640 {
1641 char *tmpnew = NULL;
1642
1643 if (consumerd64_libdir[0] != '\0') {
1644 char *tmp;
1645 size_t tmplen;
1646
1647 tmp = getenv("LD_LIBRARY_PATH");
1648 if (!tmp) {
1649 tmp = "";
1650 }
1651 tmplen = strlen("LD_LIBRARY_PATH=")
1652 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1653 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1654 if (!tmpnew) {
1655 ret = -ENOMEM;
1656 goto error;
1657 }
1658 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1659 strcat(tmpnew, consumerd64_libdir);
1660 if (tmp[0] != '\0') {
1661 strcat(tmpnew, ":");
1662 strcat(tmpnew, tmp);
1663 }
1664 ret = putenv(tmpnew);
1665 if (ret) {
1666 ret = -errno;
1667 goto error;
1668 }
1669 }
1670 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1671 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1672 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1673 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1674 NULL);
1675 if (consumerd64_libdir[0] != '\0') {
1676 free(tmpnew);
1677 }
1678 if (ret) {
1679 goto error;
1680 }
1681 break;
1682 }
1683 case LTTNG_CONSUMER32_UST:
1684 {
1685 char *tmpnew = NULL;
1686
1687 if (consumerd32_libdir[0] != '\0') {
1688 char *tmp;
1689 size_t tmplen;
1690
1691 tmp = getenv("LD_LIBRARY_PATH");
1692 if (!tmp) {
1693 tmp = "";
1694 }
1695 tmplen = strlen("LD_LIBRARY_PATH=")
1696 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1697 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1698 if (!tmpnew) {
1699 ret = -ENOMEM;
1700 goto error;
1701 }
1702 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1703 strcat(tmpnew, consumerd32_libdir);
1704 if (tmp[0] != '\0') {
1705 strcat(tmpnew, ":");
1706 strcat(tmpnew, tmp);
1707 }
1708 ret = putenv(tmpnew);
1709 if (ret) {
1710 ret = -errno;
1711 goto error;
1712 }
1713 }
1714 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1715 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1716 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1717 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1718 NULL);
1719 if (consumerd32_libdir[0] != '\0') {
1720 free(tmpnew);
1721 }
1722 if (ret) {
1723 goto error;
1724 }
1725 break;
1726 }
1727 default:
1728 PERROR("unknown consumer type");
1729 exit(EXIT_FAILURE);
1730 }
1731 if (errno != 0) {
1732 PERROR("kernel start consumer exec");
1733 }
1734 exit(EXIT_FAILURE);
1735 } else if (pid > 0) {
1736 ret = pid;
1737 } else {
1738 PERROR("start consumer fork");
1739 ret = -errno;
1740 }
1741 error:
1742 return ret;
1743 }
1744
1745 /*
1746 * Spawn the consumerd daemon and session daemon thread.
1747 */
1748 static int start_consumerd(struct consumer_data *consumer_data)
1749 {
1750 int ret;
1751
1752 pthread_mutex_lock(&consumer_data->pid_mutex);
1753 if (consumer_data->pid != 0) {
1754 pthread_mutex_unlock(&consumer_data->pid_mutex);
1755 goto end;
1756 }
1757
1758 ret = spawn_consumerd(consumer_data);
1759 if (ret < 0) {
1760 ERR("Spawning consumerd failed");
1761 pthread_mutex_unlock(&consumer_data->pid_mutex);
1762 goto error;
1763 }
1764
1765 /* Setting up the consumer_data pid */
1766 consumer_data->pid = ret;
1767 DBG2("Consumer pid %d", consumer_data->pid);
1768 pthread_mutex_unlock(&consumer_data->pid_mutex);
1769
1770 DBG2("Spawning consumer control thread");
1771 ret = spawn_consumer_thread(consumer_data);
1772 if (ret < 0) {
1773 ERR("Fatal error spawning consumer control thread");
1774 goto error;
1775 }
1776
1777 end:
1778 return 0;
1779
1780 error:
1781 return ret;
1782 }
1783
1784 /*
1785 * Check version of the lttng-modules.
1786 */
1787 static int validate_lttng_modules_version(void)
1788 {
1789 return kernel_validate_version(kernel_tracer_fd);
1790 }
1791
1792 /*
1793 * Setup necessary data for kernel tracer action.
1794 */
1795 static int init_kernel_tracer(void)
1796 {
1797 int ret;
1798
1799 /* Modprobe lttng kernel modules */
1800 ret = modprobe_lttng_control();
1801 if (ret < 0) {
1802 goto error;
1803 }
1804
1805 /* Open debugfs lttng */
1806 kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
1807 if (kernel_tracer_fd < 0) {
1808 DBG("Failed to open %s", module_proc_lttng);
1809 ret = -1;
1810 goto error_open;
1811 }
1812
1813 /* Validate kernel version */
1814 ret = validate_lttng_modules_version();
1815 if (ret < 0) {
1816 goto error_version;
1817 }
1818
1819 ret = modprobe_lttng_data();
1820 if (ret < 0) {
1821 goto error_modules;
1822 }
1823
1824 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1825 return 0;
1826
1827 error_version:
1828 modprobe_remove_lttng_control();
1829 ret = close(kernel_tracer_fd);
1830 if (ret) {
1831 PERROR("close");
1832 }
1833 kernel_tracer_fd = -1;
1834 return LTTCOMM_KERN_VERSION;
1835
1836 error_modules:
1837 ret = close(kernel_tracer_fd);
1838 if (ret) {
1839 PERROR("close");
1840 }
1841
1842 error_open:
1843 modprobe_remove_lttng_control();
1844
1845 error:
1846 WARN("No kernel tracer available");
1847 kernel_tracer_fd = -1;
1848 return LTTCOMM_KERN_NA;
1849 }
1850
1851 /*
1852 * Init tracing by creating trace directory and sending fds kernel consumer.
1853 */
1854 static int init_kernel_tracing(struct ltt_kernel_session *session)
1855 {
1856 int ret = 0;
1857
1858 if (session->consumer_fds_sent == 0) {
1859 /*
1860 * Assign default kernel consumer socket if no consumer assigned to the
1861 * kernel session. At this point, it's NOT suppose to be 0 but this is
1862 * an extra security check.
1863 */
1864 if (session->consumer_fd == 0) {
1865 session->consumer_fd = kconsumer_data.cmd_sock;
1866 }
1867
1868 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1869 if (ret < 0) {
1870 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1871 goto error;
1872 }
1873
1874 session->consumer_fds_sent = 1;
1875 }
1876
1877 error:
1878 return ret;
1879 }
1880
1881 /*
1882 * Create an UST session and add it to the session ust list.
1883 */
1884 static int create_ust_session(struct ltt_session *session,
1885 struct lttng_domain *domain)
1886 {
1887 struct ltt_ust_session *lus = NULL;
1888 int ret;
1889
1890 switch (domain->type) {
1891 case LTTNG_DOMAIN_UST:
1892 break;
1893 default:
1894 ret = LTTCOMM_UNKNOWN_DOMAIN;
1895 goto error;
1896 }
1897
1898 DBG("Creating UST session");
1899
1900 lus = trace_ust_create_session(session->path, session->id, domain);
1901 if (lus == NULL) {
1902 ret = LTTCOMM_UST_SESS_FAIL;
1903 goto error;
1904 }
1905
1906 ret = run_as_mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1907 session->uid, session->gid);
1908 if (ret < 0) {
1909 if (ret != -EEXIST) {
1910 ERR("Trace directory creation error");
1911 ret = LTTCOMM_UST_SESS_FAIL;
1912 goto error;
1913 }
1914 }
1915
1916 /* The domain type dictate different actions on session creation */
1917 switch (domain->type) {
1918 case LTTNG_DOMAIN_UST:
1919 /* No ustctl for the global UST domain */
1920 break;
1921 default:
1922 ERR("Unknown UST domain on create session %d", domain->type);
1923 goto error;
1924 }
1925 lus->uid = session->uid;
1926 lus->gid = session->gid;
1927 session->ust_session = lus;
1928
1929 return LTTCOMM_OK;
1930
1931 error:
1932 free(lus);
1933 return ret;
1934 }
1935
1936 /*
1937 * Create a kernel tracer session then create the default channel.
1938 */
1939 static int create_kernel_session(struct ltt_session *session)
1940 {
1941 int ret;
1942
1943 DBG("Creating kernel session");
1944
1945 ret = kernel_create_session(session, kernel_tracer_fd);
1946 if (ret < 0) {
1947 ret = LTTCOMM_KERN_SESS_FAIL;
1948 goto error;
1949 }
1950
1951 /* Set kernel consumer socket fd */
1952 if (kconsumer_data.cmd_sock) {
1953 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1954 }
1955
1956 ret = run_as_mkdir_recursive(session->kernel_session->trace_path,
1957 S_IRWXU | S_IRWXG, session->uid, session->gid);
1958 if (ret < 0) {
1959 if (ret != -EEXIST) {
1960 ERR("Trace directory creation error");
1961 goto error;
1962 }
1963 }
1964 session->kernel_session->uid = session->uid;
1965 session->kernel_session->gid = session->gid;
1966
1967 error:
1968 return ret;
1969 }
1970
1971 /*
1972 * Check if the UID or GID match the session. Root user has access to all
1973 * sessions.
1974 */
1975 static int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid)
1976 {
1977 if (uid != session->uid && gid != session->gid && uid != 0) {
1978 return 0;
1979 } else {
1980 return 1;
1981 }
1982 }
1983
1984 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
1985 {
1986 unsigned int i = 0;
1987 struct ltt_session *session;
1988
1989 DBG("Counting number of available session for UID %d GID %d",
1990 uid, gid);
1991 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1992 /*
1993 * Only list the sessions the user can control.
1994 */
1995 if (!session_access_ok(session, uid, gid)) {
1996 continue;
1997 }
1998 i++;
1999 }
2000 return i;
2001 }
2002
2003 /*
2004 * Using the session list, filled a lttng_session array to send back to the
2005 * client for session listing.
2006 *
2007 * The session list lock MUST be acquired before calling this function. Use
2008 * session_lock_list() and session_unlock_list().
2009 */
2010 static void list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2011 gid_t gid)
2012 {
2013 unsigned int i = 0;
2014 struct ltt_session *session;
2015
2016 DBG("Getting all available session for UID %d GID %d",
2017 uid, gid);
2018 /*
2019 * Iterate over session list and append data after the control struct in
2020 * the buffer.
2021 */
2022 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2023 /*
2024 * Only list the sessions the user can control.
2025 */
2026 if (!session_access_ok(session, uid, gid)) {
2027 continue;
2028 }
2029 strncpy(sessions[i].path, session->path, PATH_MAX);
2030 sessions[i].path[PATH_MAX - 1] = '\0';
2031 strncpy(sessions[i].name, session->name, NAME_MAX);
2032 sessions[i].name[NAME_MAX - 1] = '\0';
2033 sessions[i].enabled = session->enabled;
2034 i++;
2035 }
2036 }
2037
2038 /*
2039 * Fill lttng_channel array of all channels.
2040 */
2041 static void list_lttng_channels(int domain, struct ltt_session *session,
2042 struct lttng_channel *channels)
2043 {
2044 int i = 0;
2045 struct ltt_kernel_channel *kchan;
2046
2047 DBG("Listing channels for session %s", session->name);
2048
2049 switch (domain) {
2050 case LTTNG_DOMAIN_KERNEL:
2051 /* Kernel channels */
2052 if (session->kernel_session != NULL) {
2053 cds_list_for_each_entry(kchan,
2054 &session->kernel_session->channel_list.head, list) {
2055 /* Copy lttng_channel struct to array */
2056 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2057 channels[i].enabled = kchan->enabled;
2058 i++;
2059 }
2060 }
2061 break;
2062 case LTTNG_DOMAIN_UST:
2063 {
2064 struct lttng_ht_iter iter;
2065 struct ltt_ust_channel *uchan;
2066
2067 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
2068 &iter.iter, uchan, node.node) {
2069 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2070 channels[i].attr.overwrite = uchan->attr.overwrite;
2071 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2072 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2073 channels[i].attr.switch_timer_interval =
2074 uchan->attr.switch_timer_interval;
2075 channels[i].attr.read_timer_interval =
2076 uchan->attr.read_timer_interval;
2077 channels[i].enabled = uchan->enabled;
2078 switch (uchan->attr.output) {
2079 case LTTNG_UST_MMAP:
2080 default:
2081 channels[i].attr.output = LTTNG_EVENT_MMAP;
2082 break;
2083 }
2084 i++;
2085 }
2086 break;
2087 }
2088 default:
2089 break;
2090 }
2091 }
2092
2093 /*
2094 * Create a list of ust global domain events.
2095 */
2096 static int list_lttng_ust_global_events(char *channel_name,
2097 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2098 {
2099 int i = 0, ret = 0;
2100 unsigned int nb_event = 0;
2101 struct lttng_ht_iter iter;
2102 struct lttng_ht_node_str *node;
2103 struct ltt_ust_channel *uchan;
2104 struct ltt_ust_event *uevent;
2105 struct lttng_event *tmp;
2106
2107 DBG("Listing UST global events for channel %s", channel_name);
2108
2109 rcu_read_lock();
2110
2111 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2112 node = lttng_ht_iter_get_node_str(&iter);
2113 if (node == NULL) {
2114 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2115 goto error;
2116 }
2117
2118 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2119
2120 nb_event += lttng_ht_get_count(uchan->events);
2121
2122 if (nb_event == 0) {
2123 ret = nb_event;
2124 goto error;
2125 }
2126
2127 DBG3("Listing UST global %d events", nb_event);
2128
2129 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2130 if (tmp == NULL) {
2131 ret = -LTTCOMM_FATAL;
2132 goto error;
2133 }
2134
2135 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2136 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2137 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2138 tmp[i].enabled = uevent->enabled;
2139 switch (uevent->attr.instrumentation) {
2140 case LTTNG_UST_TRACEPOINT:
2141 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2142 break;
2143 case LTTNG_UST_PROBE:
2144 tmp[i].type = LTTNG_EVENT_PROBE;
2145 break;
2146 case LTTNG_UST_FUNCTION:
2147 tmp[i].type = LTTNG_EVENT_FUNCTION;
2148 break;
2149 }
2150 tmp[i].loglevel = uevent->attr.loglevel;
2151 switch (uevent->attr.loglevel_type) {
2152 case LTTNG_UST_LOGLEVEL_ALL:
2153 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2154 break;
2155 case LTTNG_UST_LOGLEVEL_RANGE:
2156 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
2157 break;
2158 case LTTNG_UST_LOGLEVEL_SINGLE:
2159 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
2160 break;
2161 }
2162 i++;
2163 }
2164
2165 ret = nb_event;
2166 *events = tmp;
2167
2168 error:
2169 rcu_read_unlock();
2170 return ret;
2171 }
2172
2173 /*
2174 * Fill lttng_event array of all kernel events in the channel.
2175 */
2176 static int list_lttng_kernel_events(char *channel_name,
2177 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2178 {
2179 int i = 0, ret;
2180 unsigned int nb_event;
2181 struct ltt_kernel_event *event;
2182 struct ltt_kernel_channel *kchan;
2183
2184 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2185 if (kchan == NULL) {
2186 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2187 goto error;
2188 }
2189
2190 nb_event = kchan->event_count;
2191
2192 DBG("Listing events for channel %s", kchan->channel->name);
2193
2194 if (nb_event == 0) {
2195 ret = nb_event;
2196 goto error;
2197 }
2198
2199 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2200 if (*events == NULL) {
2201 ret = LTTCOMM_FATAL;
2202 goto error;
2203 }
2204
2205 /* Kernel channels */
2206 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2207 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2208 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2209 (*events)[i].enabled = event->enabled;
2210 switch (event->event->instrumentation) {
2211 case LTTNG_KERNEL_TRACEPOINT:
2212 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2213 break;
2214 case LTTNG_KERNEL_KPROBE:
2215 case LTTNG_KERNEL_KRETPROBE:
2216 (*events)[i].type = LTTNG_EVENT_PROBE;
2217 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2218 sizeof(struct lttng_kernel_kprobe));
2219 break;
2220 case LTTNG_KERNEL_FUNCTION:
2221 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2222 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2223 sizeof(struct lttng_kernel_function));
2224 break;
2225 case LTTNG_KERNEL_NOOP:
2226 (*events)[i].type = LTTNG_EVENT_NOOP;
2227 break;
2228 case LTTNG_KERNEL_SYSCALL:
2229 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2230 break;
2231 case LTTNG_KERNEL_ALL:
2232 assert(0);
2233 break;
2234 }
2235 i++;
2236 }
2237
2238 return nb_event;
2239
2240 error:
2241 return ret;
2242 }
2243
2244 /*
2245 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2246 */
2247 static int cmd_disable_channel(struct ltt_session *session,
2248 int domain, char *channel_name)
2249 {
2250 int ret;
2251 struct ltt_ust_session *usess;
2252
2253 usess = session->ust_session;
2254
2255 switch (domain) {
2256 case LTTNG_DOMAIN_KERNEL:
2257 {
2258 ret = channel_kernel_disable(session->kernel_session,
2259 channel_name);
2260 if (ret != LTTCOMM_OK) {
2261 goto error;
2262 }
2263
2264 kernel_wait_quiescent(kernel_tracer_fd);
2265 break;
2266 }
2267 case LTTNG_DOMAIN_UST:
2268 {
2269 struct ltt_ust_channel *uchan;
2270 struct lttng_ht *chan_ht;
2271
2272 chan_ht = usess->domain_global.channels;
2273
2274 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2275 if (uchan == NULL) {
2276 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2277 goto error;
2278 }
2279
2280 ret = channel_ust_disable(usess, domain, uchan);
2281 if (ret != LTTCOMM_OK) {
2282 goto error;
2283 }
2284 break;
2285 }
2286 #if 0
2287 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2288 case LTTNG_DOMAIN_UST_EXEC_NAME:
2289 case LTTNG_DOMAIN_UST_PID:
2290 #endif
2291 default:
2292 ret = LTTCOMM_UNKNOWN_DOMAIN;
2293 goto error;
2294 }
2295
2296 ret = LTTCOMM_OK;
2297
2298 error:
2299 return ret;
2300 }
2301
2302 /*
2303 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2304 */
2305 static int cmd_enable_channel(struct ltt_session *session,
2306 int domain, struct lttng_channel *attr)
2307 {
2308 int ret;
2309 struct ltt_ust_session *usess = session->ust_session;
2310 struct lttng_ht *chan_ht;
2311
2312 DBG("Enabling channel %s for session %s", attr->name, session->name);
2313
2314 switch (domain) {
2315 case LTTNG_DOMAIN_KERNEL:
2316 {
2317 struct ltt_kernel_channel *kchan;
2318
2319 kchan = trace_kernel_get_channel_by_name(attr->name,
2320 session->kernel_session);
2321 if (kchan == NULL) {
2322 ret = channel_kernel_create(session->kernel_session,
2323 attr, kernel_poll_pipe[1]);
2324 } else {
2325 ret = channel_kernel_enable(session->kernel_session, kchan);
2326 }
2327
2328 if (ret != LTTCOMM_OK) {
2329 goto error;
2330 }
2331
2332 kernel_wait_quiescent(kernel_tracer_fd);
2333 break;
2334 }
2335 case LTTNG_DOMAIN_UST:
2336 {
2337 struct ltt_ust_channel *uchan;
2338
2339 chan_ht = usess->domain_global.channels;
2340
2341 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2342 if (uchan == NULL) {
2343 ret = channel_ust_create(usess, domain, attr);
2344 } else {
2345 ret = channel_ust_enable(usess, domain, uchan);
2346 }
2347 break;
2348 }
2349 #if 0
2350 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2351 case LTTNG_DOMAIN_UST_EXEC_NAME:
2352 case LTTNG_DOMAIN_UST_PID:
2353 #endif
2354 default:
2355 ret = LTTCOMM_UNKNOWN_DOMAIN;
2356 goto error;
2357 }
2358
2359 error:
2360 return ret;
2361 }
2362
2363 /*
2364 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2365 */
2366 static int cmd_disable_event(struct ltt_session *session, int domain,
2367 char *channel_name, char *event_name)
2368 {
2369 int ret;
2370
2371 switch (domain) {
2372 case LTTNG_DOMAIN_KERNEL:
2373 {
2374 struct ltt_kernel_channel *kchan;
2375 struct ltt_kernel_session *ksess;
2376
2377 ksess = session->kernel_session;
2378
2379 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2380 if (kchan == NULL) {
2381 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2382 goto error;
2383 }
2384
2385 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2386 if (ret != LTTCOMM_OK) {
2387 goto error;
2388 }
2389
2390 kernel_wait_quiescent(kernel_tracer_fd);
2391 break;
2392 }
2393 case LTTNG_DOMAIN_UST:
2394 {
2395 struct ltt_ust_channel *uchan;
2396 struct ltt_ust_session *usess;
2397
2398 usess = session->ust_session;
2399
2400 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2401 channel_name);
2402 if (uchan == NULL) {
2403 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2404 goto error;
2405 }
2406
2407 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2408 if (ret != LTTCOMM_OK) {
2409 goto error;
2410 }
2411
2412 DBG3("Disable UST event %s in channel %s completed", event_name,
2413 channel_name);
2414 break;
2415 }
2416 #if 0
2417 case LTTNG_DOMAIN_UST_EXEC_NAME:
2418 case LTTNG_DOMAIN_UST_PID:
2419 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2420 #endif
2421 default:
2422 ret = LTTCOMM_UND;
2423 goto error;
2424 }
2425
2426 ret = LTTCOMM_OK;
2427
2428 error:
2429 return ret;
2430 }
2431
2432 /*
2433 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2434 */
2435 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2436 char *channel_name)
2437 {
2438 int ret;
2439
2440 switch (domain) {
2441 case LTTNG_DOMAIN_KERNEL:
2442 {
2443 struct ltt_kernel_session *ksess;
2444 struct ltt_kernel_channel *kchan;
2445
2446 ksess = session->kernel_session;
2447
2448 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2449 if (kchan == NULL) {
2450 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2451 goto error;
2452 }
2453
2454 ret = event_kernel_disable_all(ksess, kchan);
2455 if (ret != LTTCOMM_OK) {
2456 goto error;
2457 }
2458
2459 kernel_wait_quiescent(kernel_tracer_fd);
2460 break;
2461 }
2462 case LTTNG_DOMAIN_UST:
2463 {
2464 struct ltt_ust_session *usess;
2465 struct ltt_ust_channel *uchan;
2466
2467 usess = session->ust_session;
2468
2469 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2470 channel_name);
2471 if (uchan == NULL) {
2472 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2473 goto error;
2474 }
2475
2476 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2477 if (ret != 0) {
2478 goto error;
2479 }
2480
2481 DBG3("Disable all UST events in channel %s completed", channel_name);
2482
2483 break;
2484 }
2485 #if 0
2486 case LTTNG_DOMAIN_UST_EXEC_NAME:
2487 case LTTNG_DOMAIN_UST_PID:
2488 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2489 #endif
2490 default:
2491 ret = LTTCOMM_UND;
2492 goto error;
2493 }
2494
2495 ret = LTTCOMM_OK;
2496
2497 error:
2498 return ret;
2499 }
2500
2501 /*
2502 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2503 */
2504 static int cmd_add_context(struct ltt_session *session, int domain,
2505 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2506 {
2507 int ret;
2508
2509 switch (domain) {
2510 case LTTNG_DOMAIN_KERNEL:
2511 /* Add kernel context to kernel tracer */
2512 ret = context_kernel_add(session->kernel_session, ctx,
2513 event_name, channel_name);
2514 if (ret != LTTCOMM_OK) {
2515 goto error;
2516 }
2517 break;
2518 case LTTNG_DOMAIN_UST:
2519 {
2520 struct ltt_ust_session *usess = session->ust_session;
2521
2522 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2523 if (ret != LTTCOMM_OK) {
2524 goto error;
2525 }
2526 break;
2527 }
2528 #if 0
2529 case LTTNG_DOMAIN_UST_EXEC_NAME:
2530 case LTTNG_DOMAIN_UST_PID:
2531 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2532 #endif
2533 default:
2534 ret = LTTCOMM_UND;
2535 goto error;
2536 }
2537
2538 ret = LTTCOMM_OK;
2539
2540 error:
2541 return ret;
2542 }
2543
2544 /*
2545 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2546 */
2547 static int cmd_enable_event(struct ltt_session *session, int domain,
2548 char *channel_name, struct lttng_event *event)
2549 {
2550 int ret;
2551 struct lttng_channel *attr;
2552 struct ltt_ust_session *usess = session->ust_session;
2553
2554 switch (domain) {
2555 case LTTNG_DOMAIN_KERNEL:
2556 {
2557 struct ltt_kernel_channel *kchan;
2558
2559 kchan = trace_kernel_get_channel_by_name(channel_name,
2560 session->kernel_session);
2561 if (kchan == NULL) {
2562 attr = channel_new_default_attr(domain);
2563 if (attr == NULL) {
2564 ret = LTTCOMM_FATAL;
2565 goto error;
2566 }
2567 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2568
2569 /* This call will notify the kernel thread */
2570 ret = channel_kernel_create(session->kernel_session,
2571 attr, kernel_poll_pipe[1]);
2572 if (ret != LTTCOMM_OK) {
2573 free(attr);
2574 goto error;
2575 }
2576 free(attr);
2577 }
2578
2579 /* Get the newly created kernel channel pointer */
2580 kchan = trace_kernel_get_channel_by_name(channel_name,
2581 session->kernel_session);
2582 if (kchan == NULL) {
2583 /* This sould not happen... */
2584 ret = LTTCOMM_FATAL;
2585 goto error;
2586 }
2587
2588 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2589 event);
2590 if (ret != LTTCOMM_OK) {
2591 goto error;
2592 }
2593
2594 kernel_wait_quiescent(kernel_tracer_fd);
2595 break;
2596 }
2597 case LTTNG_DOMAIN_UST:
2598 {
2599 struct lttng_channel *attr;
2600 struct ltt_ust_channel *uchan;
2601
2602 /* Get channel from global UST domain */
2603 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2604 channel_name);
2605 if (uchan == NULL) {
2606 /* Create default channel */
2607 attr = channel_new_default_attr(domain);
2608 if (attr == NULL) {
2609 ret = LTTCOMM_FATAL;
2610 goto error;
2611 }
2612 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2613 attr->name[NAME_MAX - 1] = '\0';
2614
2615 ret = channel_ust_create(usess, domain, attr);
2616 if (ret != LTTCOMM_OK) {
2617 free(attr);
2618 goto error;
2619 }
2620 free(attr);
2621
2622 /* Get the newly created channel reference back */
2623 uchan = trace_ust_find_channel_by_name(
2624 usess->domain_global.channels, channel_name);
2625 if (uchan == NULL) {
2626 /* Something is really wrong */
2627 ret = LTTCOMM_FATAL;
2628 goto error;
2629 }
2630 }
2631
2632 /* At this point, the session and channel exist on the tracer */
2633 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2634 if (ret != LTTCOMM_OK) {
2635 goto error;
2636 }
2637 break;
2638 }
2639 #if 0
2640 case LTTNG_DOMAIN_UST_EXEC_NAME:
2641 case LTTNG_DOMAIN_UST_PID:
2642 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2643 #endif
2644 default:
2645 ret = LTTCOMM_UND;
2646 goto error;
2647 }
2648
2649 ret = LTTCOMM_OK;
2650
2651 error:
2652 return ret;
2653 }
2654
2655 /*
2656 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2657 */
2658 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2659 char *channel_name, int event_type)
2660 {
2661 int ret;
2662 struct ltt_kernel_channel *kchan;
2663
2664 switch (domain) {
2665 case LTTNG_DOMAIN_KERNEL:
2666 kchan = trace_kernel_get_channel_by_name(channel_name,
2667 session->kernel_session);
2668 if (kchan == NULL) {
2669 /* This call will notify the kernel thread */
2670 ret = channel_kernel_create(session->kernel_session, NULL,
2671 kernel_poll_pipe[1]);
2672 if (ret != LTTCOMM_OK) {
2673 goto error;
2674 }
2675
2676 /* Get the newly created kernel channel pointer */
2677 kchan = trace_kernel_get_channel_by_name(channel_name,
2678 session->kernel_session);
2679 if (kchan == NULL) {
2680 /* This sould not happen... */
2681 ret = LTTCOMM_FATAL;
2682 goto error;
2683 }
2684
2685 }
2686
2687 switch (event_type) {
2688 case LTTNG_EVENT_SYSCALL:
2689 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2690 kchan, kernel_tracer_fd);
2691 break;
2692 case LTTNG_EVENT_TRACEPOINT:
2693 /*
2694 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2695 * events already registered to the channel.
2696 */
2697 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2698 kchan, kernel_tracer_fd);
2699 break;
2700 case LTTNG_EVENT_ALL:
2701 /* Enable syscalls and tracepoints */
2702 ret = event_kernel_enable_all(session->kernel_session,
2703 kchan, kernel_tracer_fd);
2704 break;
2705 default:
2706 ret = LTTCOMM_KERN_ENABLE_FAIL;
2707 goto error;
2708 }
2709
2710 /* Manage return value */
2711 if (ret != LTTCOMM_OK) {
2712 goto error;
2713 }
2714
2715 kernel_wait_quiescent(kernel_tracer_fd);
2716 break;
2717 case LTTNG_DOMAIN_UST:
2718 {
2719 struct lttng_channel *attr;
2720 struct ltt_ust_channel *uchan;
2721 struct ltt_ust_session *usess = session->ust_session;
2722
2723 /* Get channel from global UST domain */
2724 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2725 channel_name);
2726 if (uchan == NULL) {
2727 /* Create default channel */
2728 attr = channel_new_default_attr(domain);
2729 if (attr == NULL) {
2730 ret = LTTCOMM_FATAL;
2731 goto error;
2732 }
2733 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2734 attr->name[NAME_MAX - 1] = '\0';
2735
2736 /* Use the internal command enable channel */
2737 ret = channel_ust_create(usess, domain, attr);
2738 if (ret != LTTCOMM_OK) {
2739 free(attr);
2740 goto error;
2741 }
2742 free(attr);
2743
2744 /* Get the newly created channel reference back */
2745 uchan = trace_ust_find_channel_by_name(
2746 usess->domain_global.channels, channel_name);
2747 if (uchan == NULL) {
2748 /* Something is really wrong */
2749 ret = LTTCOMM_FATAL;
2750 goto error;
2751 }
2752 }
2753
2754 /* At this point, the session and channel exist on the tracer */
2755
2756 switch (event_type) {
2757 case LTTNG_EVENT_ALL:
2758 case LTTNG_EVENT_TRACEPOINT:
2759 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2760 if (ret != LTTCOMM_OK) {
2761 goto error;
2762 }
2763 break;
2764 default:
2765 ret = LTTCOMM_UST_ENABLE_FAIL;
2766 goto error;
2767 }
2768
2769 /* Manage return value */
2770 if (ret != LTTCOMM_OK) {
2771 goto error;
2772 }
2773
2774 break;
2775 }
2776 #if 0
2777 case LTTNG_DOMAIN_UST_EXEC_NAME:
2778 case LTTNG_DOMAIN_UST_PID:
2779 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2780 #endif
2781 default:
2782 ret = LTTCOMM_UND;
2783 goto error;
2784 }
2785
2786 ret = LTTCOMM_OK;
2787
2788 error:
2789 return ret;
2790 }
2791
2792 /*
2793 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2794 */
2795 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2796 {
2797 int ret;
2798 ssize_t nb_events = 0;
2799
2800 switch (domain) {
2801 case LTTNG_DOMAIN_KERNEL:
2802 nb_events = kernel_list_events(kernel_tracer_fd, events);
2803 if (nb_events < 0) {
2804 ret = LTTCOMM_KERN_LIST_FAIL;
2805 goto error;
2806 }
2807 break;
2808 case LTTNG_DOMAIN_UST:
2809 nb_events = ust_app_list_events(events);
2810 if (nb_events < 0) {
2811 ret = LTTCOMM_UST_LIST_FAIL;
2812 goto error;
2813 }
2814 break;
2815 default:
2816 ret = LTTCOMM_UND;
2817 goto error;
2818 }
2819
2820 return nb_events;
2821
2822 error:
2823 /* Return negative value to differentiate return code */
2824 return -ret;
2825 }
2826
2827 /*
2828 * Command LTTNG_START_TRACE processed by the client thread.
2829 */
2830 static int cmd_start_trace(struct ltt_session *session)
2831 {
2832 int ret;
2833 struct ltt_kernel_session *ksession;
2834 struct ltt_ust_session *usess;
2835
2836 /* Short cut */
2837 ksession = session->kernel_session;
2838 usess = session->ust_session;
2839
2840 if (session->enabled) {
2841 ret = LTTCOMM_UST_START_FAIL;
2842 goto error;
2843 }
2844
2845 session->enabled = 1;
2846
2847 /* Kernel tracing */
2848 if (ksession != NULL) {
2849 struct ltt_kernel_channel *kchan;
2850
2851 /* Open kernel metadata */
2852 if (ksession->metadata == NULL) {
2853 ret = kernel_open_metadata(ksession, ksession->trace_path);
2854 if (ret < 0) {
2855 ret = LTTCOMM_KERN_META_FAIL;
2856 goto error;
2857 }
2858 }
2859
2860 /* Open kernel metadata stream */
2861 if (ksession->metadata_stream_fd == 0) {
2862 ret = kernel_open_metadata_stream(ksession);
2863 if (ret < 0) {
2864 ERR("Kernel create metadata stream failed");
2865 ret = LTTCOMM_KERN_STREAM_FAIL;
2866 goto error;
2867 }
2868 }
2869
2870 /* For each channel */
2871 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2872 if (kchan->stream_count == 0) {
2873 ret = kernel_open_channel_stream(kchan);
2874 if (ret < 0) {
2875 ret = LTTCOMM_KERN_STREAM_FAIL;
2876 goto error;
2877 }
2878 /* Update the stream global counter */
2879 ksession->stream_count_global += ret;
2880 }
2881 }
2882
2883 /* Setup kernel consumer socket and send fds to it */
2884 ret = init_kernel_tracing(ksession);
2885 if (ret < 0) {
2886 ret = LTTCOMM_KERN_START_FAIL;
2887 goto error;
2888 }
2889
2890 /* This start the kernel tracing */
2891 ret = kernel_start_session(ksession);
2892 if (ret < 0) {
2893 ret = LTTCOMM_KERN_START_FAIL;
2894 goto error;
2895 }
2896
2897 /* Quiescent wait after starting trace */
2898 kernel_wait_quiescent(kernel_tracer_fd);
2899 }
2900
2901 /* Flag session that trace should start automatically */
2902 if (usess) {
2903 usess->start_trace = 1;
2904
2905 ret = ust_app_start_trace_all(usess);
2906 if (ret < 0) {
2907 ret = LTTCOMM_UST_START_FAIL;
2908 goto error;
2909 }
2910 }
2911
2912 ret = LTTCOMM_OK;
2913
2914 error:
2915 return ret;
2916 }
2917
2918 /*
2919 * Command LTTNG_STOP_TRACE processed by the client thread.
2920 */
2921 static int cmd_stop_trace(struct ltt_session *session)
2922 {
2923 int ret;
2924 struct ltt_kernel_channel *kchan;
2925 struct ltt_kernel_session *ksession;
2926 struct ltt_ust_session *usess;
2927
2928 /* Short cut */
2929 ksession = session->kernel_session;
2930 usess = session->ust_session;
2931
2932 if (!session->enabled) {
2933 ret = LTTCOMM_UST_STOP_FAIL;
2934 goto error;
2935 }
2936
2937 session->enabled = 0;
2938
2939 /* Kernel tracer */
2940 if (ksession != NULL) {
2941 DBG("Stop kernel tracing");
2942
2943 /* Flush all buffers before stopping */
2944 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2945 if (ret < 0) {
2946 ERR("Kernel metadata flush failed");
2947 }
2948
2949 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2950 ret = kernel_flush_buffer(kchan);
2951 if (ret < 0) {
2952 ERR("Kernel flush buffer error");
2953 }
2954 }
2955
2956 ret = kernel_stop_session(ksession);
2957 if (ret < 0) {
2958 ret = LTTCOMM_KERN_STOP_FAIL;
2959 goto error;
2960 }
2961
2962 kernel_wait_quiescent(kernel_tracer_fd);
2963 }
2964
2965 if (usess) {
2966 usess->start_trace = 0;
2967
2968 ret = ust_app_stop_trace_all(usess);
2969 if (ret < 0) {
2970 ret = LTTCOMM_UST_STOP_FAIL;
2971 goto error;
2972 }
2973 }
2974
2975 ret = LTTCOMM_OK;
2976
2977 error:
2978 return ret;
2979 }
2980
2981 /*
2982 * Command LTTNG_CREATE_SESSION processed by the client thread.
2983 */
2984 static int cmd_create_session(char *name, char *path, lttng_sock_cred *creds)
2985 {
2986 int ret;
2987
2988 ret = session_create(name, path, LTTNG_SOCK_GET_UID_CRED(creds),
2989 LTTNG_SOCK_GET_GID_CRED(creds));
2990 if (ret != LTTCOMM_OK) {
2991 goto error;
2992 }
2993
2994 ret = LTTCOMM_OK;
2995
2996 error:
2997 return ret;
2998 }
2999
3000 /*
3001 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3002 */
3003 static int cmd_destroy_session(struct ltt_session *session, char *name)
3004 {
3005 int ret;
3006
3007 /* Clean kernel session teardown */
3008 teardown_kernel_session(session);
3009 /* UST session teardown */
3010 teardown_ust_session(session);
3011
3012 /*
3013 * Must notify the kernel thread here to update it's poll setin order
3014 * to remove the channel(s)' fd just destroyed.
3015 */
3016 ret = notify_thread_pipe(kernel_poll_pipe[1]);
3017 if (ret < 0) {
3018 PERROR("write kernel poll pipe");
3019 }
3020
3021 ret = session_destroy(session);
3022
3023 return ret;
3024 }
3025
3026 /*
3027 * Command LTTNG_CALIBRATE processed by the client thread.
3028 */
3029 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3030 {
3031 int ret;
3032
3033 switch (domain) {
3034 case LTTNG_DOMAIN_KERNEL:
3035 {
3036 struct lttng_kernel_calibrate kcalibrate;
3037
3038 kcalibrate.type = calibrate->type;
3039 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3040 if (ret < 0) {
3041 ret = LTTCOMM_KERN_ENABLE_FAIL;
3042 goto error;
3043 }
3044 break;
3045 }
3046 case LTTNG_DOMAIN_UST:
3047 {
3048 struct lttng_ust_calibrate ucalibrate;
3049
3050 ucalibrate.type = calibrate->type;
3051 ret = ust_app_calibrate_glb(&ucalibrate);
3052 if (ret < 0) {
3053 ret = LTTCOMM_UST_CALIBRATE_FAIL;
3054 goto error;
3055 }
3056 break;
3057 }
3058 default:
3059 ret = LTTCOMM_UND;
3060 goto error;
3061 }
3062
3063 ret = LTTCOMM_OK;
3064
3065 error:
3066 return ret;
3067 }
3068
3069 /*
3070 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3071 */
3072 static int cmd_register_consumer(struct ltt_session *session, int domain,
3073 char *sock_path)
3074 {
3075 int ret, sock;
3076
3077 switch (domain) {
3078 case LTTNG_DOMAIN_KERNEL:
3079 /* Can't register a consumer if there is already one */
3080 if (session->kernel_session->consumer_fds_sent != 0) {
3081 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3082 goto error;
3083 }
3084
3085 sock = lttcomm_connect_unix_sock(sock_path);
3086 if (sock < 0) {
3087 ret = LTTCOMM_CONNECT_FAIL;
3088 goto error;
3089 }
3090
3091 session->kernel_session->consumer_fd = sock;
3092 break;
3093 default:
3094 /* TODO: Userspace tracing */
3095 ret = LTTCOMM_UND;
3096 goto error;
3097 }
3098
3099 ret = LTTCOMM_OK;
3100
3101 error:
3102 return ret;
3103 }
3104
3105 /*
3106 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3107 */
3108 static ssize_t cmd_list_domains(struct ltt_session *session,
3109 struct lttng_domain **domains)
3110 {
3111 int ret, index = 0;
3112 ssize_t nb_dom = 0;
3113
3114 if (session->kernel_session != NULL) {
3115 DBG3("Listing domains found kernel domain");
3116 nb_dom++;
3117 }
3118
3119 if (session->ust_session != NULL) {
3120 DBG3("Listing domains found UST global domain");
3121 nb_dom++;
3122 }
3123
3124 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3125 if (*domains == NULL) {
3126 ret = -LTTCOMM_FATAL;
3127 goto error;
3128 }
3129
3130 if (session->kernel_session != NULL) {
3131 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3132 index++;
3133 }
3134
3135 if (session->ust_session != NULL) {
3136 (*domains)[index].type = LTTNG_DOMAIN_UST;
3137 index++;
3138 }
3139
3140 return nb_dom;
3141
3142 error:
3143 return ret;
3144 }
3145
3146 /*
3147 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3148 */
3149 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3150 struct lttng_channel **channels)
3151 {
3152 int ret;
3153 ssize_t nb_chan = 0;
3154
3155 switch (domain) {
3156 case LTTNG_DOMAIN_KERNEL:
3157 if (session->kernel_session != NULL) {
3158 nb_chan = session->kernel_session->channel_count;
3159 }
3160 DBG3("Number of kernel channels %zd", nb_chan);
3161 break;
3162 case LTTNG_DOMAIN_UST:
3163 if (session->ust_session != NULL) {
3164 nb_chan = lttng_ht_get_count(
3165 session->ust_session->domain_global.channels);
3166 }
3167 DBG3("Number of UST global channels %zd", nb_chan);
3168 break;
3169 default:
3170 *channels = NULL;
3171 ret = -LTTCOMM_UND;
3172 goto error;
3173 }
3174
3175 if (nb_chan > 0) {
3176 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3177 if (*channels == NULL) {
3178 ret = -LTTCOMM_FATAL;
3179 goto error;
3180 }
3181
3182 list_lttng_channels(domain, session, *channels);
3183 } else {
3184 *channels = NULL;
3185 }
3186
3187 return nb_chan;
3188
3189 error:
3190 return ret;
3191 }
3192
3193 /*
3194 * Command LTTNG_LIST_EVENTS processed by the client thread.
3195 */
3196 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3197 char *channel_name, struct lttng_event **events)
3198 {
3199 int ret = 0;
3200 ssize_t nb_event = 0;
3201
3202 switch (domain) {
3203 case LTTNG_DOMAIN_KERNEL:
3204 if (session->kernel_session != NULL) {
3205 nb_event = list_lttng_kernel_events(channel_name,
3206 session->kernel_session, events);
3207 }
3208 break;
3209 case LTTNG_DOMAIN_UST:
3210 {
3211 if (session->ust_session != NULL) {
3212 nb_event = list_lttng_ust_global_events(channel_name,
3213 &session->ust_session->domain_global, events);
3214 }
3215 break;
3216 }
3217 default:
3218 ret = -LTTCOMM_UND;
3219 goto error;
3220 }
3221
3222 ret = nb_event;
3223
3224 error:
3225 return ret;
3226 }
3227
3228 /*
3229 * Process the command requested by the lttng client within the command
3230 * context structure. This function make sure that the return structure (llm)
3231 * is set and ready for transmission before returning.
3232 *
3233 * Return any error encountered or 0 for success.
3234 */
3235 static int process_client_msg(struct command_ctx *cmd_ctx)
3236 {
3237 int ret = LTTCOMM_OK;
3238 int need_tracing_session = 1;
3239 int need_domain;
3240
3241 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3242
3243 switch (cmd_ctx->lsm->cmd_type) {
3244 case LTTNG_CREATE_SESSION:
3245 case LTTNG_DESTROY_SESSION:
3246 case LTTNG_LIST_SESSIONS:
3247 case LTTNG_LIST_DOMAINS:
3248 case LTTNG_START_TRACE:
3249 case LTTNG_STOP_TRACE:
3250 need_domain = 0;
3251 break;
3252 default:
3253 need_domain = 1;
3254 }
3255
3256 if (opt_no_kernel && need_domain
3257 && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
3258 ret = LTTCOMM_KERN_NA;
3259 goto error;
3260 }
3261
3262 /*
3263 * Check for command that don't needs to allocate a returned payload. We do
3264 * this here so we don't have to make the call for no payload at each