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