Fix runas namespace
[lttng-tools.git] / lttng-sessiond / main.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the Free
7 * Software Foundation; only version 2 of the License.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
16 * Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18
19 #define _GNU_SOURCE
20 #include <fcntl.h>
21 #include <getopt.h>
22 #include <grp.h>
23 #include <limits.h>
24 #include <pthread.h>
25 #include <semaphore.h>
26 #include <signal.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <sys/mman.h>
31 #include <sys/mount.h>
32 #include <sys/resource.h>
33 #include <sys/socket.h>
34 #include <sys/stat.h>
35 #include <sys/types.h>
36 #include <sys/wait.h>
37 #include <urcu/futex.h>
38 #include <unistd.h>
39 #include <config.h>
40
41 #include <lttng-consumerd.h>
42 #include <lttng-ht.h>
43 #include <lttng-sessiond-comm.h>
44 #include <lttng/lttng-consumer.h>
45
46 #include <lttngerr.h>
47 #include "common/runas.h"
48
49 #include "channel.h"
50 #include "compat/poll.h"
51 #include "context.h"
52 #include "event.h"
53 #include "futex.h"
54 #include "kernel.h"
55 #include "lttng-sessiond.h"
56 #include "shm.h"
57 #include "ust-app.h"
58 #include "ust-ctl.h"
59 #include "utils.h"
60
61 #define CONSUMERD_FILE "lttng-consumerd"
62
63 struct consumer_data {
64 enum lttng_consumer_type type;
65
66 pthread_t thread; /* Worker thread interacting with the consumer */
67 sem_t sem;
68
69 /* Mutex to control consumerd pid assignation */
70 pthread_mutex_t pid_mutex;
71 pid_t pid;
72
73 int err_sock;
74 int cmd_sock;
75
76 /* consumer error and command Unix socket path */
77 char err_unix_sock_path[PATH_MAX];
78 char cmd_unix_sock_path[PATH_MAX];
79 };
80
81 /* Const values */
82 const char default_home_dir[] = DEFAULT_HOME_DIR;
83 const char default_tracing_group[] = LTTNG_DEFAULT_TRACING_GROUP;
84 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
85 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
86
87 /* Variables */
88 int opt_verbose; /* Not static for lttngerr.h */
89 int opt_verbose_consumer; /* Not static for lttngerr.h */
90 int opt_quiet; /* Not static for lttngerr.h */
91
92 const char *progname;
93 const char *opt_tracing_group;
94 static int opt_sig_parent;
95 static int opt_daemon;
96 static int opt_no_kernel;
97 static int is_root; /* Set to 1 if the daemon is running as root */
98 static pid_t ppid; /* Parent PID for --sig-parent option */
99 static char *rundir;
100
101 /* Consumer daemon specific control data */
102 static struct consumer_data kconsumer_data = {
103 .type = LTTNG_CONSUMER_KERNEL,
104 .err_unix_sock_path = KCONSUMERD_ERR_SOCK_PATH,
105 .cmd_unix_sock_path = KCONSUMERD_CMD_SOCK_PATH,
106 };
107 static struct consumer_data ustconsumer64_data = {
108 .type = LTTNG_CONSUMER64_UST,
109 .err_unix_sock_path = USTCONSUMERD64_ERR_SOCK_PATH,
110 .cmd_unix_sock_path = USTCONSUMERD64_CMD_SOCK_PATH,
111 };
112 static struct consumer_data ustconsumer32_data = {
113 .type = LTTNG_CONSUMER32_UST,
114 .err_unix_sock_path = USTCONSUMERD32_ERR_SOCK_PATH,
115 .cmd_unix_sock_path = USTCONSUMERD32_CMD_SOCK_PATH,
116 };
117
118 static int dispatch_thread_exit;
119
120 /* Global application Unix socket path */
121 static char apps_unix_sock_path[PATH_MAX];
122 /* Global client Unix socket path */
123 static char client_unix_sock_path[PATH_MAX];
124 /* global wait shm path for UST */
125 static char wait_shm_path[PATH_MAX];
126
127 /* Sockets and FDs */
128 static int client_sock;
129 static int apps_sock;
130 static int kernel_tracer_fd;
131 static int kernel_poll_pipe[2];
132
133 /*
134 * Quit pipe for all threads. This permits a single cancellation point
135 * for all threads when receiving an event on the pipe.
136 */
137 static int thread_quit_pipe[2];
138
139 /*
140 * This pipe is used to inform the thread managing application communication
141 * that a command is queued and ready to be processed.
142 */
143 static int apps_cmd_pipe[2];
144
145 /* Pthread, Mutexes and Semaphores */
146 static pthread_t apps_thread;
147 static pthread_t reg_apps_thread;
148 static pthread_t client_thread;
149 static pthread_t kernel_thread;
150 static pthread_t dispatch_thread;
151
152
153 /*
154 * UST registration command queue. This queue is tied with a futex and uses a N
155 * wakers / 1 waiter implemented and detailed in futex.c/.h
156 *
157 * The thread_manage_apps and thread_dispatch_ust_registration interact with
158 * this queue and the wait/wake scheme.
159 */
160 static struct ust_cmd_queue ust_cmd_queue;
161
162 /*
163 * Pointer initialized before thread creation.
164 *
165 * This points to the tracing session list containing the session count and a
166 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
167 * MUST NOT be taken if you call a public function in session.c.
168 *
169 * The lock is nested inside the structure: session_list_ptr->lock. Please use
170 * session_lock_list and session_unlock_list for lock acquisition.
171 */
172 static struct ltt_session_list *session_list_ptr;
173
174 int ust_consumerd64_fd = -1;
175 int ust_consumerd32_fd = -1;
176
177 static const char *consumerd32_bin = CONFIG_CONSUMERD32_BIN;
178 static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
179 static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
180 static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
181
182 static
183 void setup_consumerd_path(void)
184 {
185 const char *bin, *libdir;
186
187 /*
188 * Allow INSTALL_BIN_PATH to be used as a target path for the
189 * native architecture size consumer if CONFIG_CONSUMER*_PATH
190 * has not been defined.
191 */
192 #if (CAA_BITS_PER_LONG == 32)
193 if (!consumerd32_bin[0]) {
194 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
195 }
196 if (!consumerd32_libdir[0]) {
197 consumerd32_libdir = INSTALL_LIB_PATH;
198 }
199 #elif (CAA_BITS_PER_LONG == 64)
200 if (!consumerd64_bin[0]) {
201 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
202 }
203 if (!consumerd64_libdir[0]) {
204 consumerd64_libdir = INSTALL_LIB_PATH;
205 }
206 #else
207 #error "Unknown bitness"
208 #endif
209
210 /*
211 * runtime env. var. overrides the build default.
212 */
213 bin = getenv("LTTNG_CONSUMERD32_BIN");
214 if (bin) {
215 consumerd32_bin = bin;
216 }
217 bin = getenv("LTTNG_CONSUMERD64_BIN");
218 if (bin) {
219 consumerd64_bin = bin;
220 }
221 libdir = getenv("LTTNG_TOOLS_CONSUMERD32_LIBDIR");
222 if (libdir) {
223 consumerd32_libdir = libdir;
224 }
225 libdir = getenv("LTTNG_TOOLS_CONSUMERD64_LIBDIR");
226 if (libdir) {
227 consumerd64_libdir = libdir;
228 }
229 }
230
231 /*
232 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
233 */
234 static int create_thread_poll_set(struct lttng_poll_event *events,
235 unsigned int size)
236 {
237 int ret;
238
239 if (events == NULL || size == 0) {
240 ret = -1;
241 goto error;
242 }
243
244 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
245 if (ret < 0) {
246 goto error;
247 }
248
249 /* Add quit pipe */
250 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
251 if (ret < 0) {
252 goto error;
253 }
254
255 return 0;
256
257 error:
258 return ret;
259 }
260
261 /*
262 * Check if the thread quit pipe was triggered.
263 *
264 * Return 1 if it was triggered else 0;
265 */
266 static int check_thread_quit_pipe(int fd, uint32_t events)
267 {
268 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
269 return 1;
270 }
271
272 return 0;
273 }
274
275 /*
276 * Remove modules in reverse load order.
277 */
278 static int modprobe_remove_kernel_modules(void)
279 {
280 int ret = 0, i;
281 char modprobe[256];
282
283 for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
284 ret = snprintf(modprobe, sizeof(modprobe),
285 "/sbin/modprobe -r -q %s",
286 kernel_modules_list[i].name);
287 if (ret < 0) {
288 perror("snprintf modprobe -r");
289 goto error;
290 }
291 modprobe[sizeof(modprobe) - 1] = '\0';
292 ret = system(modprobe);
293 if (ret == -1) {
294 ERR("Unable to launch modprobe -r for module %s",
295 kernel_modules_list[i].name);
296 } else if (kernel_modules_list[i].required
297 && WEXITSTATUS(ret) != 0) {
298 ERR("Unable to remove module %s",
299 kernel_modules_list[i].name);
300 } else {
301 DBG("Modprobe removal successful %s",
302 kernel_modules_list[i].name);
303 }
304 }
305
306 error:
307 return ret;
308 }
309
310 /*
311 * Return group ID of the tracing group or -1 if not found.
312 */
313 static gid_t allowed_group(void)
314 {
315 struct group *grp;
316
317 if (opt_tracing_group) {
318 grp = getgrnam(opt_tracing_group);
319 } else {
320 grp = getgrnam(default_tracing_group);
321 }
322 if (!grp) {
323 return -1;
324 } else {
325 return grp->gr_gid;
326 }
327 }
328
329 /*
330 * Init thread quit pipe.
331 *
332 * Return -1 on error or 0 if all pipes are created.
333 */
334 static int init_thread_quit_pipe(void)
335 {
336 int ret;
337
338 ret = pipe2(thread_quit_pipe, O_CLOEXEC);
339 if (ret < 0) {
340 perror("thread quit pipe");
341 goto error;
342 }
343
344 error:
345 return ret;
346 }
347
348 /*
349 * Complete teardown of a kernel session. This free all data structure related
350 * to a kernel session and update counter.
351 */
352 static void teardown_kernel_session(struct ltt_session *session)
353 {
354 if (!session->kernel_session) {
355 DBG3("No kernel session when tearingdown session");
356 return;
357 }
358
359 DBG("Tearing down kernel session");
360
361 /*
362 * If a custom kernel consumer was registered, close the socket before
363 * tearing down the complete kernel session structure
364 */
365 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
366 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
367 }
368
369 trace_kernel_destroy_session(session->kernel_session);
370 }
371
372 /*
373 * Complete teardown of all UST sessions. This will free everything on his path
374 * and destroy the core essence of all ust sessions :)
375 */
376 static void teardown_ust_session(struct ltt_session *session)
377 {
378 int ret;
379
380 if (!session->ust_session) {
381 DBG3("No UST session when tearingdown session");
382 return;
383 }
384
385 DBG("Tearing down UST session(s)");
386
387 ret = ust_app_destroy_trace_all(session->ust_session);
388 if (ret) {
389 ERR("Error in ust_app_destroy_trace_all");
390 }
391
392 trace_ust_destroy_session(session->ust_session);
393 }
394
395 /*
396 * Stop all threads by closing the thread quit pipe.
397 */
398 static void stop_threads(void)
399 {
400 int ret;
401
402 /* Stopping all threads */
403 DBG("Terminating all threads");
404 ret = notify_thread_pipe(thread_quit_pipe[1]);
405 if (ret < 0) {
406 ERR("write error on thread quit pipe");
407 }
408
409 /* Dispatch thread */
410 dispatch_thread_exit = 1;
411 futex_nto1_wake(&ust_cmd_queue.futex);
412 }
413
414 /*
415 * Cleanup the daemon
416 */
417 static void cleanup(void)
418 {
419 int ret;
420 char *cmd;
421 struct ltt_session *sess, *stmp;
422
423 DBG("Cleaning up");
424
425 DBG("Removing %s directory", rundir);
426 ret = asprintf(&cmd, "rm -rf %s", rundir);
427 if (ret < 0) {
428 ERR("asprintf failed. Something is really wrong!");
429 }
430
431 /* Remove lttng run directory */
432 ret = system(cmd);
433 if (ret < 0) {
434 ERR("Unable to clean %s", rundir);
435 }
436 free(cmd);
437
438 DBG("Cleaning up all session");
439
440 /* Destroy session list mutex */
441 if (session_list_ptr != NULL) {
442 pthread_mutex_destroy(&session_list_ptr->lock);
443
444 /* Cleanup ALL session */
445 cds_list_for_each_entry_safe(sess, stmp,
446 &session_list_ptr->head, list) {
447 teardown_kernel_session(sess);
448 teardown_ust_session(sess);
449 free(sess);
450 }
451 }
452
453 DBG("Closing all UST sockets");
454 ust_app_clean_list();
455
456 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
457
458 if (is_root && !opt_no_kernel) {
459 DBG2("Closing kernel fd");
460 close(kernel_tracer_fd);
461 DBG("Unloading kernel modules");
462 modprobe_remove_kernel_modules();
463 }
464
465 close(thread_quit_pipe[0]);
466 close(thread_quit_pipe[1]);
467
468 /* <fun> */
469 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
470 "Matthew, BEET driven development works!%c[%dm",
471 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
472 /* </fun> */
473 }
474
475 /*
476 * Send data on a unix socket using the liblttsessiondcomm API.
477 *
478 * Return lttcomm error code.
479 */
480 static int send_unix_sock(int sock, void *buf, size_t len)
481 {
482 /* Check valid length */
483 if (len <= 0) {
484 return -1;
485 }
486
487 return lttcomm_send_unix_sock(sock, buf, len);
488 }
489
490 /*
491 * Free memory of a command context structure.
492 */
493 static void clean_command_ctx(struct command_ctx **cmd_ctx)
494 {
495 DBG("Clean command context structure");
496 if (*cmd_ctx) {
497 if ((*cmd_ctx)->llm) {
498 free((*cmd_ctx)->llm);
499 }
500 if ((*cmd_ctx)->lsm) {
501 free((*cmd_ctx)->lsm);
502 }
503 free(*cmd_ctx);
504 *cmd_ctx = NULL;
505 }
506 }
507
508 /*
509 * Send all stream fds of kernel channel to the consumer.
510 */
511 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
512 int sock, struct ltt_kernel_channel *channel,
513 uid_t uid, gid_t gid)
514 {
515 int ret;
516 struct ltt_kernel_stream *stream;
517 struct lttcomm_consumer_msg lkm;
518
519 DBG("Sending streams of channel %s to kernel consumer",
520 channel->channel->name);
521
522 /* Send channel */
523 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
524 lkm.u.channel.channel_key = channel->fd;
525 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
526 lkm.u.channel.mmap_len = 0; /* for kernel */
527 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
528 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
529 if (ret < 0) {
530 perror("send consumer channel");
531 goto error;
532 }
533
534 /* Send streams */
535 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
536 if (!stream->fd) {
537 continue;
538 }
539 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
540 lkm.u.stream.channel_key = channel->fd;
541 lkm.u.stream.stream_key = stream->fd;
542 lkm.u.stream.state = stream->state;
543 lkm.u.stream.output = channel->channel->attr.output;
544 lkm.u.stream.mmap_len = 0; /* for kernel */
545 lkm.u.stream.uid = uid;
546 lkm.u.stream.gid = gid;
547 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
548 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
549 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
550 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
551 if (ret < 0) {
552 perror("send consumer stream");
553 goto error;
554 }
555 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
556 if (ret < 0) {
557 perror("send consumer stream ancillary data");
558 goto error;
559 }
560 }
561
562 DBG("consumer channel streams sent");
563
564 return 0;
565
566 error:
567 return ret;
568 }
569
570 /*
571 * Send all stream fds of the kernel session to the consumer.
572 */
573 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
574 struct ltt_kernel_session *session)
575 {
576 int ret;
577 struct ltt_kernel_channel *chan;
578 struct lttcomm_consumer_msg lkm;
579 int sock = session->consumer_fd;
580
581 DBG("Sending metadata stream fd");
582
583 /* Extra protection. It's NOT supposed to be set to 0 at this point */
584 if (session->consumer_fd == 0) {
585 session->consumer_fd = consumer_data->cmd_sock;
586 }
587
588 if (session->metadata_stream_fd != 0) {
589 /* Send metadata channel fd */
590 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
591 lkm.u.channel.channel_key = session->metadata->fd;
592 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
593 lkm.u.channel.mmap_len = 0; /* for kernel */
594 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
595 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
596 if (ret < 0) {
597 perror("send consumer channel");
598 goto error;
599 }
600
601 /* Send metadata stream fd */
602 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
603 lkm.u.stream.channel_key = session->metadata->fd;
604 lkm.u.stream.stream_key = session->metadata_stream_fd;
605 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
606 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
607 lkm.u.stream.mmap_len = 0; /* for kernel */
608 lkm.u.stream.uid = session->uid;
609 lkm.u.stream.gid = session->gid;
610 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
611 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
612 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
613 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
614 if (ret < 0) {
615 perror("send consumer stream");
616 goto error;
617 }
618 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
619 if (ret < 0) {
620 perror("send consumer stream");
621 goto error;
622 }
623 }
624
625 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
626 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
627 session->uid, session->gid);
628 if (ret < 0) {
629 goto error;
630 }
631 }
632
633 DBG("consumer fds (metadata and channel streams) sent");
634
635 return 0;
636
637 error:
638 return ret;
639 }
640
641 /*
642 * Notify UST applications using the shm mmap futex.
643 */
644 static int notify_ust_apps(int active)
645 {
646 char *wait_shm_mmap;
647
648 DBG("Notifying applications of session daemon state: %d", active);
649
650 /* See shm.c for this call implying mmap, shm and futex calls */
651 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
652 if (wait_shm_mmap == NULL) {
653 goto error;
654 }
655
656 /* Wake waiting process */
657 futex_wait_update((int32_t *) wait_shm_mmap, active);
658
659 /* Apps notified successfully */
660 return 0;
661
662 error:
663 return -1;
664 }
665
666 /*
667 * Setup the outgoing data buffer for the response (llm) by allocating the
668 * right amount of memory and copying the original information from the lsm
669 * structure.
670 *
671 * Return total size of the buffer pointed by buf.
672 */
673 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
674 {
675 int ret, buf_size;
676
677 buf_size = size;
678
679 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
680 if (cmd_ctx->llm == NULL) {
681 perror("zmalloc");
682 ret = -ENOMEM;
683 goto error;
684 }
685
686 /* Copy common data */
687 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
688 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
689
690 cmd_ctx->llm->data_size = size;
691 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
692
693 return buf_size;
694
695 error:
696 return ret;
697 }
698
699 /*
700 * Update the kernel poll set of all channel fd available over all tracing
701 * session. Add the wakeup pipe at the end of the set.
702 */
703 static int update_kernel_poll(struct lttng_poll_event *events)
704 {
705 int ret;
706 struct ltt_session *session;
707 struct ltt_kernel_channel *channel;
708
709 DBG("Updating kernel poll set");
710
711 session_lock_list();
712 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
713 session_lock(session);
714 if (session->kernel_session == NULL) {
715 session_unlock(session);
716 continue;
717 }
718
719 cds_list_for_each_entry(channel,
720 &session->kernel_session->channel_list.head, list) {
721 /* Add channel fd to the kernel poll set */
722 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
723 if (ret < 0) {
724 session_unlock(session);
725 goto error;
726 }
727 DBG("Channel fd %d added to kernel set", channel->fd);
728 }
729 session_unlock(session);
730 }
731 session_unlock_list();
732
733 return 0;
734
735 error:
736 session_unlock_list();
737 return -1;
738 }
739
740 /*
741 * Find the channel fd from 'fd' over all tracing session. When found, check
742 * for new channel stream and send those stream fds to the kernel consumer.
743 *
744 * Useful for CPU hotplug feature.
745 */
746 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
747 {
748 int ret = 0;
749 struct ltt_session *session;
750 struct ltt_kernel_channel *channel;
751
752 DBG("Updating kernel streams for channel fd %d", fd);
753
754 session_lock_list();
755 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
756 session_lock(session);
757 if (session->kernel_session == NULL) {
758 session_unlock(session);
759 continue;
760 }
761
762 /* This is not suppose to be 0 but this is an extra security check */
763 if (session->kernel_session->consumer_fd == 0) {
764 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
765 }
766
767 cds_list_for_each_entry(channel,
768 &session->kernel_session->channel_list.head, list) {
769 if (channel->fd == fd) {
770 DBG("Channel found, updating kernel streams");
771 ret = kernel_open_channel_stream(channel);
772 if (ret < 0) {
773 goto error;
774 }
775
776 /*
777 * Have we already sent fds to the consumer? If yes, it means
778 * that tracing is started so it is safe to send our updated
779 * stream fds.
780 */
781 if (session->kernel_session->consumer_fds_sent == 1) {
782 ret = send_kconsumer_channel_streams(consumer_data,
783 session->kernel_session->consumer_fd, channel,
784 session->uid, session->gid);
785 if (ret < 0) {
786 goto error;
787 }
788 }
789 goto error;
790 }
791 }
792 session_unlock(session);
793 }
794 session_unlock_list();
795 return ret;
796
797 error:
798 session_unlock(session);
799 session_unlock_list();
800 return ret;
801 }
802
803 /*
804 * For each tracing session, update newly registered apps.
805 */
806 static void update_ust_app(int app_sock)
807 {
808 struct ltt_session *sess, *stmp;
809
810 /* For all tracing session(s) */
811 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
812 if (sess->ust_session) {
813 ust_app_global_update(sess->ust_session, app_sock);
814 }
815 }
816 }
817
818 /*
819 * This thread manage event coming from the kernel.
820 *
821 * Features supported in this thread:
822 * -) CPU Hotplug
823 */
824 static void *thread_manage_kernel(void *data)
825 {
826 int ret, i, pollfd, update_poll_flag = 1;
827 uint32_t revents, nb_fd;
828 char tmp;
829 struct lttng_poll_event events;
830
831 DBG("Thread manage kernel started");
832
833 ret = create_thread_poll_set(&events, 2);
834 if (ret < 0) {
835 goto error;
836 }
837
838 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
839 if (ret < 0) {
840 goto error;
841 }
842
843 while (1) {
844 if (update_poll_flag == 1) {
845 /*
846 * Reset number of fd in the poll set. Always 2 since there is the thread
847 * quit pipe and the kernel pipe.
848 */
849 events.nb_fd = 2;
850
851 ret = update_kernel_poll(&events);
852 if (ret < 0) {
853 goto error;
854 }
855 update_poll_flag = 0;
856 }
857
858 nb_fd = LTTNG_POLL_GETNB(&events);
859
860 DBG("Thread kernel polling on %d fds", nb_fd);
861
862 /* Zeroed the poll events */
863 lttng_poll_reset(&events);
864
865 /* Poll infinite value of time */
866 ret = lttng_poll_wait(&events, -1);
867 if (ret < 0) {
868 goto error;
869 } else if (ret == 0) {
870 /* Should not happen since timeout is infinite */
871 ERR("Return value of poll is 0 with an infinite timeout.\n"
872 "This should not have happened! Continuing...");
873 continue;
874 }
875
876 for (i = 0; i < nb_fd; i++) {
877 /* Fetch once the poll data */
878 revents = LTTNG_POLL_GETEV(&events, i);
879 pollfd = LTTNG_POLL_GETFD(&events, i);
880
881 /* Thread quit pipe has been closed. Killing thread. */
882 ret = check_thread_quit_pipe(pollfd, revents);
883 if (ret) {
884 goto error;
885 }
886
887 /* Check for data on kernel pipe */
888 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
889 ret = read(kernel_poll_pipe[0], &tmp, 1);
890 update_poll_flag = 1;
891 continue;
892 } else {
893 /*
894 * New CPU detected by the kernel. Adding kernel stream to
895 * kernel session and updating the kernel consumer
896 */
897 if (revents & LPOLLIN) {
898 ret = update_kernel_stream(&kconsumer_data, pollfd);
899 if (ret < 0) {
900 continue;
901 }
902 break;
903 /*
904 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
905 * and unregister kernel stream at this point.
906 */
907 }
908 }
909 }
910 }
911
912 error:
913 DBG("Kernel thread dying");
914 close(kernel_poll_pipe[0]);
915 close(kernel_poll_pipe[1]);
916
917 lttng_poll_clean(&events);
918
919 return NULL;
920 }
921
922 /*
923 * This thread manage the consumer error sent back to the session daemon.
924 */
925 static void *thread_manage_consumer(void *data)
926 {
927 int sock = 0, i, ret, pollfd;
928 uint32_t revents, nb_fd;
929 enum lttcomm_return_code code;
930 struct lttng_poll_event events;
931 struct consumer_data *consumer_data = data;
932
933 DBG("[thread] Manage consumer started");
934
935 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
936 if (ret < 0) {
937 goto error;
938 }
939
940 /*
941 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
942 * Nothing more will be added to this poll set.
943 */
944 ret = create_thread_poll_set(&events, 2);
945 if (ret < 0) {
946 goto error;
947 }
948
949 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
950 if (ret < 0) {
951 goto error;
952 }
953
954 nb_fd = LTTNG_POLL_GETNB(&events);
955
956 /* Inifinite blocking call, waiting for transmission */
957 ret = lttng_poll_wait(&events, -1);
958 if (ret < 0) {
959 goto error;
960 }
961
962 for (i = 0; i < nb_fd; i++) {
963 /* Fetch once the poll data */
964 revents = LTTNG_POLL_GETEV(&events, i);
965 pollfd = LTTNG_POLL_GETFD(&events, i);
966
967 /* Thread quit pipe has been closed. Killing thread. */
968 ret = check_thread_quit_pipe(pollfd, revents);
969 if (ret) {
970 goto error;
971 }
972
973 /* Event on the registration socket */
974 if (pollfd == consumer_data->err_sock) {
975 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
976 ERR("consumer err socket poll error");
977 goto error;
978 }
979 }
980 }
981
982 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
983 if (sock < 0) {
984 goto error;
985 }
986
987 DBG2("Receiving code from consumer err_sock");
988
989 /* Getting status code from kconsumerd */
990 ret = lttcomm_recv_unix_sock(sock, &code,
991 sizeof(enum lttcomm_return_code));
992 if (ret <= 0) {
993 goto error;
994 }
995
996 if (code == CONSUMERD_COMMAND_SOCK_READY) {
997 consumer_data->cmd_sock =
998 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
999 if (consumer_data->cmd_sock < 0) {
1000 sem_post(&consumer_data->sem);
1001 PERROR("consumer connect");
1002 goto error;
1003 }
1004 /* Signal condition to tell that the kconsumerd is ready */
1005 sem_post(&consumer_data->sem);
1006 DBG("consumer command socket ready");
1007 } else {
1008 ERR("consumer error when waiting for SOCK_READY : %s",
1009 lttcomm_get_readable_code(-code));
1010 goto error;
1011 }
1012
1013 /* Remove the kconsumerd error sock since we've established a connexion */
1014 ret = lttng_poll_del(&events, consumer_data->err_sock);
1015 if (ret < 0) {
1016 goto error;
1017 }
1018
1019 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1020 if (ret < 0) {
1021 goto error;
1022 }
1023
1024 /* Update number of fd */
1025 nb_fd = LTTNG_POLL_GETNB(&events);
1026
1027 /* Inifinite blocking call, waiting for transmission */
1028 ret = lttng_poll_wait(&events, -1);
1029 if (ret < 0) {
1030 goto error;
1031 }
1032
1033 for (i = 0; i < nb_fd; i++) {
1034 /* Fetch once the poll data */
1035 revents = LTTNG_POLL_GETEV(&events, i);
1036 pollfd = LTTNG_POLL_GETFD(&events, i);
1037
1038 /* Thread quit pipe has been closed. Killing thread. */
1039 ret = check_thread_quit_pipe(pollfd, revents);
1040 if (ret) {
1041 goto error;
1042 }
1043
1044 /* Event on the kconsumerd socket */
1045 if (pollfd == sock) {
1046 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1047 ERR("consumer err socket second poll error");
1048 goto error;
1049 }
1050 }
1051 }
1052
1053 /* Wait for any kconsumerd error */
1054 ret = lttcomm_recv_unix_sock(sock, &code,
1055 sizeof(enum lttcomm_return_code));
1056 if (ret <= 0) {
1057 ERR("consumer closed the command socket");
1058 goto error;
1059 }
1060
1061 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1062
1063 error:
1064 DBG("consumer thread dying");
1065 close(consumer_data->err_sock);
1066 close(consumer_data->cmd_sock);
1067 close(sock);
1068
1069 unlink(consumer_data->err_unix_sock_path);
1070 unlink(consumer_data->cmd_unix_sock_path);
1071 consumer_data->pid = 0;
1072
1073 lttng_poll_clean(&events);
1074
1075 return NULL;
1076 }
1077
1078 /*
1079 * This thread manage application communication.
1080 */
1081 static void *thread_manage_apps(void *data)
1082 {
1083 int i, ret, pollfd;
1084 uint32_t revents, nb_fd;
1085 struct ust_command ust_cmd;
1086 struct lttng_poll_event events;
1087
1088 DBG("[thread] Manage application started");
1089
1090 rcu_register_thread();
1091 rcu_thread_online();
1092
1093 ret = create_thread_poll_set(&events, 2);
1094 if (ret < 0) {
1095 goto error;
1096 }
1097
1098 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1099 if (ret < 0) {
1100 goto error;
1101 }
1102
1103 while (1) {
1104 /* Zeroed the events structure */
1105 lttng_poll_reset(&events);
1106
1107 nb_fd = LTTNG_POLL_GETNB(&events);
1108
1109 DBG("Apps thread polling on %d fds", nb_fd);
1110
1111 /* Inifinite blocking call, waiting for transmission */
1112 ret = lttng_poll_wait(&events, -1);
1113 if (ret < 0) {
1114 goto error;
1115 }
1116
1117 for (i = 0; i < nb_fd; i++) {
1118 /* Fetch once the poll data */
1119 revents = LTTNG_POLL_GETEV(&events, i);
1120 pollfd = LTTNG_POLL_GETFD(&events, i);
1121
1122 /* Thread quit pipe has been closed. Killing thread. */
1123 ret = check_thread_quit_pipe(pollfd, revents);
1124 if (ret) {
1125 goto error;
1126 }
1127
1128 /* Inspect the apps cmd pipe */
1129 if (pollfd == apps_cmd_pipe[0]) {
1130 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1131 ERR("Apps command pipe error");
1132 goto error;
1133 } else if (revents & LPOLLIN) {
1134 /* Empty pipe */
1135 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1136 if (ret < 0 || ret < sizeof(ust_cmd)) {
1137 perror("read apps cmd pipe");
1138 goto error;
1139 }
1140
1141 /* Register applicaton to the session daemon */
1142 ret = ust_app_register(&ust_cmd.reg_msg,
1143 ust_cmd.sock);
1144 if (ret == -ENOMEM) {
1145 goto error;
1146 } else if (ret < 0) {
1147 break;
1148 }
1149
1150 /*
1151 * Add channel(s) and event(s) to newly registered apps
1152 * from lttng global UST domain.
1153 */
1154 update_ust_app(ust_cmd.sock);
1155
1156 ret = ust_app_register_done(ust_cmd.sock);
1157 if (ret < 0) {
1158 /*
1159 * If the registration is not possible, we simply
1160 * unregister the apps and continue
1161 */
1162 ust_app_unregister(ust_cmd.sock);
1163 } else {
1164 /*
1165 * We just need here to monitor the close of the UST
1166 * socket and poll set monitor those by default.
1167 */
1168 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1169 if (ret < 0) {
1170 goto error;
1171 }
1172
1173 DBG("Apps with sock %d added to poll set",
1174 ust_cmd.sock);
1175 }
1176
1177 break;
1178 }
1179 } else {
1180 /*
1181 * At this point, we know that a registered application made
1182 * the event at poll_wait.
1183 */
1184 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1185 /* Removing from the poll set */
1186 ret = lttng_poll_del(&events, pollfd);
1187 if (ret < 0) {
1188 goto error;
1189 }
1190
1191 /* Socket closed on remote end. */
1192 ust_app_unregister(pollfd);
1193 break;
1194 }
1195 }
1196 }
1197 }
1198
1199 error:
1200 DBG("Application communication apps dying");
1201 close(apps_cmd_pipe[0]);
1202 close(apps_cmd_pipe[1]);
1203
1204 lttng_poll_clean(&events);
1205
1206 rcu_thread_offline();
1207 rcu_unregister_thread();
1208 return NULL;
1209 }
1210
1211 /*
1212 * Dispatch request from the registration threads to the application
1213 * communication thread.
1214 */
1215 static void *thread_dispatch_ust_registration(void *data)
1216 {
1217 int ret;
1218 struct cds_wfq_node *node;
1219 struct ust_command *ust_cmd = NULL;
1220
1221 DBG("[thread] Dispatch UST command started");
1222
1223 while (!dispatch_thread_exit) {
1224 /* Atomically prepare the queue futex */
1225 futex_nto1_prepare(&ust_cmd_queue.futex);
1226
1227 do {
1228 /* Dequeue command for registration */
1229 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1230 if (node == NULL) {
1231 DBG("Woken up but nothing in the UST command queue");
1232 /* Continue thread execution */
1233 break;
1234 }
1235
1236 ust_cmd = caa_container_of(node, struct ust_command, node);
1237
1238 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1239 " gid:%d sock:%d name:%s (version %d.%d)",
1240 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1241 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1242 ust_cmd->sock, ust_cmd->reg_msg.name,
1243 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1244 /*
1245 * Inform apps thread of the new application registration. This
1246 * call is blocking so we can be assured that the data will be read
1247 * at some point in time or wait to the end of the world :)
1248 */
1249 ret = write(apps_cmd_pipe[1], ust_cmd,
1250 sizeof(struct ust_command));
1251 if (ret < 0) {
1252 perror("write apps cmd pipe");
1253 if (errno == EBADF) {
1254 /*
1255 * We can't inform the application thread to process
1256 * registration. We will exit or else application
1257 * registration will not occur and tracing will never
1258 * start.
1259 */
1260 goto error;
1261 }
1262 }
1263 free(ust_cmd);
1264 } while (node != NULL);
1265
1266 /* Futex wait on queue. Blocking call on futex() */
1267 futex_nto1_wait(&ust_cmd_queue.futex);
1268 }
1269
1270 error:
1271 DBG("Dispatch thread dying");
1272 return NULL;
1273 }
1274
1275 /*
1276 * This thread manage application registration.
1277 */
1278 static void *thread_registration_apps(void *data)
1279 {
1280 int sock = 0, i, ret, pollfd;
1281 uint32_t revents, nb_fd;
1282 struct lttng_poll_event events;
1283 /*
1284 * Get allocated in this thread, enqueued to a global queue, dequeued and
1285 * freed in the manage apps thread.
1286 */
1287 struct ust_command *ust_cmd = NULL;
1288
1289 DBG("[thread] Manage application registration started");
1290
1291 ret = lttcomm_listen_unix_sock(apps_sock);
1292 if (ret < 0) {
1293 goto error;
1294 }
1295
1296 /*
1297 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1298 * more will be added to this poll set.
1299 */
1300 ret = create_thread_poll_set(&events, 2);
1301 if (ret < 0) {
1302 goto error;
1303 }
1304
1305 /* Add the application registration socket */
1306 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1307 if (ret < 0) {
1308 goto error;
1309 }
1310
1311 /* Notify all applications to register */
1312 ret = notify_ust_apps(1);
1313 if (ret < 0) {
1314 ERR("Failed to notify applications or create the wait shared memory.\n"
1315 "Execution continues but there might be problem for already\n"
1316 "running applications that wishes to register.");
1317 }
1318
1319 while (1) {
1320 DBG("Accepting application registration");
1321
1322 nb_fd = LTTNG_POLL_GETNB(&events);
1323
1324 /* Inifinite blocking call, waiting for transmission */
1325 ret = lttng_poll_wait(&events, -1);
1326 if (ret < 0) {
1327 goto error;
1328 }
1329
1330 for (i = 0; i < nb_fd; i++) {
1331 /* Fetch once the poll data */
1332 revents = LTTNG_POLL_GETEV(&events, i);
1333 pollfd = LTTNG_POLL_GETFD(&events, i);
1334
1335 /* Thread quit pipe has been closed. Killing thread. */
1336 ret = check_thread_quit_pipe(pollfd, revents);
1337 if (ret) {
1338 goto error;
1339 }
1340
1341 /* Event on the registration socket */
1342 if (pollfd == apps_sock) {
1343 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1344 ERR("Register apps socket poll error");
1345 goto error;
1346 } else if (revents & LPOLLIN) {
1347 sock = lttcomm_accept_unix_sock(apps_sock);
1348 if (sock < 0) {
1349 goto error;
1350 }
1351
1352 /* Create UST registration command for enqueuing */
1353 ust_cmd = zmalloc(sizeof(struct ust_command));
1354 if (ust_cmd == NULL) {
1355 perror("ust command zmalloc");
1356 goto error;
1357 }
1358
1359 /*
1360 * Using message-based transmissions to ensure we don't
1361 * have to deal with partially received messages.
1362 */
1363 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1364 sizeof(struct ust_register_msg));
1365 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1366 if (ret < 0) {
1367 perror("lttcomm_recv_unix_sock register apps");
1368 } else {
1369 ERR("Wrong size received on apps register");
1370 }
1371 free(ust_cmd);
1372 close(sock);
1373 continue;
1374 }
1375
1376 ust_cmd->sock = sock;
1377
1378 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1379 " gid:%d sock:%d name:%s (version %d.%d)",
1380 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1381 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1382 ust_cmd->sock, ust_cmd->reg_msg.name,
1383 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1384
1385 /*
1386 * Lock free enqueue the registration request. The red pill
1387 * has been taken! This apps will be part of the *system*.
1388 */
1389 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1390
1391 /*
1392 * Wake the registration queue futex. Implicit memory
1393 * barrier with the exchange in cds_wfq_enqueue.
1394 */
1395 futex_nto1_wake(&ust_cmd_queue.futex);
1396 }
1397 }
1398 }
1399 }
1400
1401 error:
1402 DBG("UST Registration thread dying");
1403
1404 /* Notify that the registration thread is gone */
1405 notify_ust_apps(0);
1406
1407 close(apps_sock);
1408 close(sock);
1409 unlink(apps_unix_sock_path);
1410
1411 lttng_poll_clean(&events);
1412
1413 return NULL;
1414 }
1415
1416 /*
1417 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1418 * exec or it will fails.
1419 */
1420 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1421 {
1422 int ret;
1423 struct timespec timeout;
1424
1425 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1426 timeout.tv_nsec = 0;
1427
1428 /* Setup semaphore */
1429 ret = sem_init(&consumer_data->sem, 0, 0);
1430 if (ret < 0) {
1431 PERROR("sem_init consumer semaphore");
1432 goto error;
1433 }
1434
1435 ret = pthread_create(&consumer_data->thread, NULL,
1436 thread_manage_consumer, consumer_data);
1437 if (ret != 0) {
1438 PERROR("pthread_create consumer");
1439 ret = -1;
1440 goto error;
1441 }
1442
1443 /* Get time for sem_timedwait absolute timeout */
1444 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1445 if (ret < 0) {
1446 PERROR("clock_gettime spawn consumer");
1447 /* Infinite wait for the kconsumerd thread to be ready */
1448 ret = sem_wait(&consumer_data->sem);
1449 } else {
1450 /* Normal timeout if the gettime was successful */
1451 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1452 ret = sem_timedwait(&consumer_data->sem, &timeout);
1453 }
1454
1455 if (ret < 0) {
1456 if (errno == ETIMEDOUT) {
1457 /*
1458 * Call has timed out so we kill the kconsumerd_thread and return
1459 * an error.
1460 */
1461 ERR("The consumer thread was never ready. Killing it");
1462 ret = pthread_cancel(consumer_data->thread);
1463 if (ret < 0) {
1464 PERROR("pthread_cancel consumer thread");
1465 }
1466 } else {
1467 PERROR("semaphore wait failed consumer thread");
1468 }
1469 goto error;
1470 }
1471
1472 pthread_mutex_lock(&consumer_data->pid_mutex);
1473 if (consumer_data->pid == 0) {
1474 ERR("Kconsumerd did not start");
1475 pthread_mutex_unlock(&consumer_data->pid_mutex);
1476 goto error;
1477 }
1478 pthread_mutex_unlock(&consumer_data->pid_mutex);
1479
1480 return 0;
1481
1482 error:
1483 return ret;
1484 }
1485
1486 /*
1487 * Join consumer thread
1488 */
1489 static int join_consumer_thread(struct consumer_data *consumer_data)
1490 {
1491 void *status;
1492 int ret;
1493
1494 if (consumer_data->pid != 0) {
1495 ret = kill(consumer_data->pid, SIGTERM);
1496 if (ret) {
1497 ERR("Error killing consumer daemon");
1498 return ret;
1499 }
1500 return pthread_join(consumer_data->thread, &status);
1501 } else {
1502 return 0;
1503 }
1504 }
1505
1506 /*
1507 * Fork and exec a consumer daemon (consumerd).
1508 *
1509 * Return pid if successful else -1.
1510 */
1511 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1512 {
1513 int ret;
1514 pid_t pid;
1515 const char *consumer_to_use;
1516 const char *verbosity;
1517 struct stat st;
1518
1519 DBG("Spawning consumerd");
1520
1521 pid = fork();
1522 if (pid == 0) {
1523 /*
1524 * Exec consumerd.
1525 */
1526 if (opt_verbose_consumer) {
1527 verbosity = "--verbose";
1528 } else {
1529 verbosity = "--quiet";
1530 }
1531 switch (consumer_data->type) {
1532 case LTTNG_CONSUMER_KERNEL:
1533 /*
1534 * Find out which consumerd to execute. We will
1535 * first try the 64-bit path, then the
1536 * sessiond's installation directory, and
1537 * fallback on the 32-bit one,
1538 */
1539 DBG3("Looking for a kernel consumer at these locations:");
1540 DBG3(" 1) %s", consumerd64_bin);
1541 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1542 DBG3(" 3) %s", consumerd32_bin);
1543 if (stat(consumerd64_bin, &st) == 0) {
1544 DBG3("Found location #1");
1545 consumer_to_use = consumerd64_bin;
1546 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1547 DBG3("Found location #2");
1548 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1549 } else if (stat(consumerd32_bin, &st) == 0) {
1550 DBG3("Found location #3");
1551 consumer_to_use = consumerd32_bin;
1552 } else {
1553 DBG("Could not find any valid consumerd executable");
1554 break;
1555 }
1556 DBG("Using kernel consumer at: %s", consumer_to_use);
1557 execl(consumer_to_use,
1558 "lttng-consumerd", verbosity, "-k",
1559 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1560 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1561 NULL);
1562 break;
1563 case LTTNG_CONSUMER64_UST:
1564 {
1565 char *tmpnew = NULL;
1566
1567 if (consumerd64_libdir[0] != '\0') {
1568 char *tmp;
1569 size_t tmplen;
1570
1571 tmp = getenv("LD_LIBRARY_PATH");
1572 if (!tmp) {
1573 tmp = "";
1574 }
1575 tmplen = strlen("LD_LIBRARY_PATH=")
1576 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1577 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1578 if (!tmpnew) {
1579 ret = -ENOMEM;
1580 goto error;
1581 }
1582 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1583 strcat(tmpnew, consumerd64_libdir);
1584 if (tmp[0] != '\0') {
1585 strcat(tmpnew, ":");
1586 strcat(tmpnew, tmp);
1587 }
1588 ret = putenv(tmpnew);
1589 if (ret) {
1590 ret = -errno;
1591 goto error;
1592 }
1593 }
1594 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1595 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1596 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1597 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1598 NULL);
1599 if (consumerd64_libdir[0] != '\0') {
1600 free(tmpnew);
1601 }
1602 if (ret) {
1603 goto error;
1604 }
1605 break;
1606 }
1607 case LTTNG_CONSUMER32_UST:
1608 {
1609 char *tmpnew = NULL;
1610
1611 if (consumerd32_libdir[0] != '\0') {
1612 char *tmp;
1613 size_t tmplen;
1614
1615 tmp = getenv("LD_LIBRARY_PATH");
1616 if (!tmp) {
1617 tmp = "";
1618 }
1619 tmplen = strlen("LD_LIBRARY_PATH=")
1620 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1621 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1622 if (!tmpnew) {
1623 ret = -ENOMEM;
1624 goto error;
1625 }
1626 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1627 strcat(tmpnew, consumerd32_libdir);
1628 if (tmp[0] != '\0') {
1629 strcat(tmpnew, ":");
1630 strcat(tmpnew, tmp);
1631 }
1632 ret = putenv(tmpnew);
1633 if (ret) {
1634 ret = -errno;
1635 goto error;
1636 }
1637 }
1638 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1639 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1640 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1641 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1642 NULL);
1643 if (consumerd32_libdir[0] != '\0') {
1644 free(tmpnew);
1645 }
1646 if (ret) {
1647 goto error;
1648 }
1649 break;
1650 }
1651 default:
1652 perror("unknown consumer type");
1653 exit(EXIT_FAILURE);
1654 }
1655 if (errno != 0) {
1656 perror("kernel start consumer exec");
1657 }
1658 exit(EXIT_FAILURE);
1659 } else if (pid > 0) {
1660 ret = pid;
1661 } else {
1662 perror("start consumer fork");
1663 ret = -errno;
1664 }
1665 error:
1666 return ret;
1667 }
1668
1669 /*
1670 * Spawn the consumerd daemon and session daemon thread.
1671 */
1672 static int start_consumerd(struct consumer_data *consumer_data)
1673 {
1674 int ret;
1675
1676 pthread_mutex_lock(&consumer_data->pid_mutex);
1677 if (consumer_data->pid != 0) {
1678 pthread_mutex_unlock(&consumer_data->pid_mutex);
1679 goto end;
1680 }
1681
1682 ret = spawn_consumerd(consumer_data);
1683 if (ret < 0) {
1684 ERR("Spawning consumerd failed");
1685 pthread_mutex_unlock(&consumer_data->pid_mutex);
1686 goto error;
1687 }
1688
1689 /* Setting up the consumer_data pid */
1690 consumer_data->pid = ret;
1691 DBG2("Consumer pid %d", consumer_data->pid);
1692 pthread_mutex_unlock(&consumer_data->pid_mutex);
1693
1694 DBG2("Spawning consumer control thread");
1695 ret = spawn_consumer_thread(consumer_data);
1696 if (ret < 0) {
1697 ERR("Fatal error spawning consumer control thread");
1698 goto error;
1699 }
1700
1701 end:
1702 return 0;
1703
1704 error:
1705 return ret;
1706 }
1707
1708 /*
1709 * modprobe_kernel_modules
1710 */
1711 static int modprobe_kernel_modules(void)
1712 {
1713 int ret = 0, i;
1714 char modprobe[256];
1715
1716 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1717 ret = snprintf(modprobe, sizeof(modprobe),
1718 "/sbin/modprobe %s%s",
1719 kernel_modules_list[i].required ? "" : "-q ",
1720 kernel_modules_list[i].name);
1721 if (ret < 0) {
1722 perror("snprintf modprobe");
1723 goto error;
1724 }
1725 modprobe[sizeof(modprobe) - 1] = '\0';
1726 ret = system(modprobe);
1727 if (ret == -1) {
1728 ERR("Unable to launch modprobe for module %s",
1729 kernel_modules_list[i].name);
1730 } else if (kernel_modules_list[i].required
1731 && WEXITSTATUS(ret) != 0) {
1732 ERR("Unable to load module %s",
1733 kernel_modules_list[i].name);
1734 } else {
1735 DBG("Modprobe successfully %s",
1736 kernel_modules_list[i].name);
1737 }
1738 }
1739
1740 error:
1741 return ret;
1742 }
1743
1744 /*
1745 * mount_debugfs
1746 */
1747 static int mount_debugfs(char *path)
1748 {
1749 int ret;
1750 char *type = "debugfs";
1751
1752 ret = run_as_mkdir_recursive(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1753 if (ret < 0) {
1754 PERROR("Cannot create debugfs path");
1755 goto error;
1756 }
1757
1758 ret = mount(type, path, type, 0, NULL);
1759 if (ret < 0) {
1760 PERROR("Cannot mount debugfs");
1761 goto error;
1762 }
1763
1764 DBG("Mounted debugfs successfully at %s", path);
1765
1766 error:
1767 return ret;
1768 }
1769
1770 /*
1771 * Setup necessary data for kernel tracer action.
1772 */
1773 static void init_kernel_tracer(void)
1774 {
1775 int ret;
1776 char *proc_mounts = "/proc/mounts";
1777 char line[256];
1778 char *debugfs_path = NULL, *lttng_path = NULL;
1779 FILE *fp;
1780
1781 /* Detect debugfs */
1782 fp = fopen(proc_mounts, "r");
1783 if (fp == NULL) {
1784 ERR("Unable to probe %s", proc_mounts);
1785 goto error;
1786 }
1787
1788 while (fgets(line, sizeof(line), fp) != NULL) {
1789 if (strstr(line, "debugfs") != NULL) {
1790 /* Remove first string */
1791 strtok(line, " ");
1792 /* Dup string here so we can reuse line later on */
1793 debugfs_path = strdup(strtok(NULL, " "));
1794 DBG("Got debugfs path : %s", debugfs_path);
1795 break;
1796 }
1797 }
1798
1799 fclose(fp);
1800
1801 /* Mount debugfs if needded */
1802 if (debugfs_path == NULL) {
1803 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1804 if (ret < 0) {
1805 perror("asprintf debugfs path");
1806 goto error;
1807 }
1808 ret = mount_debugfs(debugfs_path);
1809 if (ret < 0) {
1810 perror("Cannot mount debugfs");
1811 goto error;
1812 }
1813 }
1814
1815 /* Modprobe lttng kernel modules */
1816 ret = modprobe_kernel_modules();
1817 if (ret < 0) {
1818 goto error;
1819 }
1820
1821 /* Setup lttng kernel path */
1822 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1823 if (ret < 0) {
1824 perror("asprintf lttng path");
1825 goto error;
1826 }
1827
1828 /* Open debugfs lttng */
1829 kernel_tracer_fd = open(lttng_path, O_RDWR);
1830 if (kernel_tracer_fd < 0) {
1831 DBG("Failed to open %s", lttng_path);
1832 goto error;
1833 }
1834
1835 free(lttng_path);
1836 free(debugfs_path);
1837 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1838 return;
1839
1840 error:
1841 if (lttng_path) {
1842 free(lttng_path);
1843 }
1844 if (debugfs_path) {
1845 free(debugfs_path);
1846 }
1847 WARN("No kernel tracer available");
1848 kernel_tracer_fd = 0;
1849 return;
1850 }
1851
1852 /*
1853 * Init tracing by creating trace directory and sending fds kernel consumer.
1854 */
1855 static int init_kernel_tracing(struct ltt_kernel_session *session)
1856 {
1857 int ret = 0;
1858
1859 if (session->consumer_fds_sent == 0) {
1860 /*
1861 * Assign default kernel consumer socket if no consumer assigned to the
1862 * kernel session. At this point, it's NOT suppose to be 0 but this is
1863 * an extra security check.
1864 */
1865 if (session->consumer_fd == 0) {
1866 session->consumer_fd = kconsumer_data.cmd_sock;
1867 }
1868
1869 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1870 if (ret < 0) {
1871 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1872 goto error;
1873 }
1874
1875 session->consumer_fds_sent = 1;
1876 }
1877
1878 error:
1879 return ret;
1880 }
1881
1882 /*
1883 * Create an UST session and add it to the session ust list.
1884 */
1885 static int create_ust_session(struct ltt_session *session,
1886 struct lttng_domain *domain)
1887 {
1888 struct ltt_ust_session *lus = NULL;
1889 int ret;
1890
1891 switch (domain->type) {
1892 case LTTNG_DOMAIN_UST:
1893 break;
1894 default:
1895 ret = LTTCOMM_UNKNOWN_DOMAIN;
1896 goto error;
1897 }
1898
1899 DBG("Creating UST session");
1900
1901 lus = trace_ust_create_session(session->path, session->id, domain);
1902 if (lus == NULL) {
1903 ret = LTTCOMM_UST_SESS_FAIL;
1904 goto error;
1905 }
1906
1907 ret = run_as_mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1908 session->uid, session->gid);
1909 if (ret < 0) {
1910 if (ret != -EEXIST) {
1911 ERR("Trace directory creation error");
1912 ret = LTTCOMM_UST_SESS_FAIL;
1913 goto error;
1914 }
1915 }
1916
1917 /* The domain type dictate different actions on session creation */
1918 switch (domain->type) {
1919 case LTTNG_DOMAIN_UST:
1920 /* No ustctl for the global UST domain */
1921 break;
1922 default:
1923 ERR("Unknown UST domain on create session %d", domain->type);
1924 goto error;
1925 }
1926 lus->uid = session->uid;
1927 lus->gid = session->gid;
1928 session->ust_session = lus;
1929
1930 return LTTCOMM_OK;
1931
1932 error:
1933 free(lus);
1934 return ret;
1935 }
1936
1937 /*
1938 * Create a kernel tracer session then create the default channel.
1939 */
1940 static int create_kernel_session(struct ltt_session *session)
1941 {
1942 int ret;
1943
1944 DBG("Creating kernel session");
1945
1946 ret = kernel_create_session(session, kernel_tracer_fd);
1947 if (ret < 0) {
1948 ret = LTTCOMM_KERN_SESS_FAIL;
1949 goto error;
1950 }
1951
1952 /* Set kernel consumer socket fd */
1953 if (kconsumer_data.cmd_sock) {
1954 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1955 }
1956
1957 ret = run_as_mkdir_recursive(session->kernel_session->trace_path,
1958 S_IRWXU | S_IRWXG, session->uid, session->gid);
1959 if (ret < 0) {
1960 if (ret != -EEXIST) {
1961 ERR("Trace directory creation error");
1962 goto error;
1963 }
1964 }
1965 session->kernel_session->uid = session->uid;
1966 session->kernel_session->gid = session->gid;
1967
1968 error:
1969 return ret;
1970 }
1971
1972 /*
1973 * Check if the UID or GID match the session. Root user has access to
1974 * all sessions.
1975 */
1976 static int session_access_ok(struct ltt_session *session,
1977 uid_t uid, gid_t gid)
1978 {
1979 if (uid != session->uid && gid != session->gid
1980 && uid != 0) {
1981 return 0;
1982 } else {
1983 return 1;
1984 }
1985 }
1986
1987 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
1988 {
1989 unsigned int i = 0;
1990 struct ltt_session *session;
1991
1992 DBG("Counting number of available session for UID %d GID %d",
1993 uid, gid);
1994 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1995 /*
1996 * Only list the sessions the user can control.
1997 */
1998 if (!session_access_ok(session, uid, gid)) {
1999 continue;
2000 }
2001 i++;
2002 }
2003 return i;
2004 }
2005
2006 /*
2007 * Using the session list, filled a lttng_session array to send back to the
2008 * client for session listing.
2009 *
2010 * The session list lock MUST be acquired before calling this function. Use
2011 * session_lock_list() and session_unlock_list().
2012 */
2013 static void list_lttng_sessions(struct lttng_session *sessions,
2014 uid_t uid, gid_t gid)
2015 {
2016 unsigned int i = 0;
2017 struct ltt_session *session;
2018
2019 DBG("Getting all available session for UID %d GID %d",
2020 uid, gid);
2021 /*
2022 * Iterate over session list and append data after the control struct in
2023 * the buffer.
2024 */
2025 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2026 /*
2027 * Only list the sessions the user can control.
2028 */
2029 if (!session_access_ok(session, uid, gid)) {
2030 continue;
2031 }
2032 strncpy(sessions[i].path, session->path, PATH_MAX);
2033 sessions[i].path[PATH_MAX - 1] = '\0';
2034 strncpy(sessions[i].name, session->name, NAME_MAX);
2035 sessions[i].name[NAME_MAX - 1] = '\0';
2036 sessions[i].enabled = session->enabled;
2037 i++;
2038 }
2039 }
2040
2041 /*
2042 * Fill lttng_channel array of all channels.
2043 */
2044 static void list_lttng_channels(int domain, struct ltt_session *session,
2045 struct lttng_channel *channels)
2046 {
2047 int i = 0;
2048 struct ltt_kernel_channel *kchan;
2049
2050 DBG("Listing channels for session %s", session->name);
2051
2052 switch (domain) {
2053 case LTTNG_DOMAIN_KERNEL:
2054 /* Kernel channels */
2055 if (session->kernel_session != NULL) {
2056 cds_list_for_each_entry(kchan,
2057 &session->kernel_session->channel_list.head, list) {
2058 /* Copy lttng_channel struct to array */
2059 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2060 channels[i].enabled = kchan->enabled;
2061 i++;
2062 }
2063 }
2064 break;
2065 case LTTNG_DOMAIN_UST:
2066 {
2067 struct lttng_ht_iter iter;
2068 struct ltt_ust_channel *uchan;
2069
2070 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
2071 &iter.iter, uchan, node.node) {
2072 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2073 channels[i].attr.overwrite = uchan->attr.overwrite;
2074 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2075 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2076 channels[i].attr.switch_timer_interval =
2077 uchan->attr.switch_timer_interval;
2078 channels[i].attr.read_timer_interval =
2079 uchan->attr.read_timer_interval;
2080 channels[i].enabled = uchan->enabled;
2081 switch (uchan->attr.output) {
2082 case LTTNG_UST_MMAP:
2083 default:
2084 channels[i].attr.output = LTTNG_EVENT_MMAP;
2085 break;
2086 }
2087 i++;
2088 }
2089 break;
2090 }
2091 default:
2092 break;
2093 }
2094 }
2095
2096 /*
2097 * Create a list of ust global domain events.
2098 */
2099 static int list_lttng_ust_global_events(char *channel_name,
2100 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2101 {
2102 int i = 0, ret = 0;
2103 unsigned int nb_event = 0;
2104 struct lttng_ht_iter iter;
2105 struct lttng_ht_node_str *node;
2106 struct ltt_ust_channel *uchan;
2107 struct ltt_ust_event *uevent;
2108 struct lttng_event *tmp;
2109
2110 DBG("Listing UST global events for channel %s", channel_name);
2111
2112 rcu_read_lock();
2113
2114 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2115 node = lttng_ht_iter_get_node_str(&iter);
2116 if (node == NULL) {
2117 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2118 goto error;
2119 }
2120
2121 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2122
2123 nb_event += lttng_ht_get_count(uchan->events);
2124
2125 if (nb_event == 0) {
2126 ret = nb_event;
2127 goto error;
2128 }
2129
2130 DBG3("Listing UST global %d events", nb_event);
2131
2132 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2133 if (tmp == NULL) {
2134 ret = -LTTCOMM_FATAL;
2135 goto error;
2136 }
2137
2138 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2139 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2140 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2141 tmp[i].enabled = uevent->enabled;
2142 switch (uevent->attr.instrumentation) {
2143 case LTTNG_UST_TRACEPOINT:
2144 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2145 break;
2146 case LTTNG_UST_PROBE:
2147 tmp[i].type = LTTNG_EVENT_PROBE;
2148 break;
2149 case LTTNG_UST_FUNCTION:
2150 tmp[i].type = LTTNG_EVENT_FUNCTION;
2151 break;
2152 case LTTNG_UST_TRACEPOINT_LOGLEVEL:
2153 tmp[i].type = LTTNG_EVENT_TRACEPOINT_LOGLEVEL;
2154 break;
2155 }
2156 i++;
2157 }
2158
2159 ret = nb_event;
2160 *events = tmp;
2161
2162 error:
2163 rcu_read_unlock();
2164 return ret;
2165 }
2166
2167 /*
2168 * Fill lttng_event array of all kernel events in the channel.
2169 */
2170 static int list_lttng_kernel_events(char *channel_name,
2171 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2172 {
2173 int i = 0, ret;
2174 unsigned int nb_event;
2175 struct ltt_kernel_event *event;
2176 struct ltt_kernel_channel *kchan;
2177
2178 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2179 if (kchan == NULL) {
2180 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2181 goto error;
2182 }
2183
2184 nb_event = kchan->event_count;
2185
2186 DBG("Listing events for channel %s", kchan->channel->name);
2187
2188 if (nb_event == 0) {
2189 ret = nb_event;
2190 goto error;
2191 }
2192
2193 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2194 if (*events == NULL) {
2195 ret = LTTCOMM_FATAL;
2196 goto error;
2197 }
2198
2199 /* Kernel channels */
2200 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2201 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2202 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2203 (*events)[i].enabled = event->enabled;
2204 switch (event->event->instrumentation) {
2205 case LTTNG_KERNEL_TRACEPOINT:
2206 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2207 break;
2208 case LTTNG_KERNEL_KPROBE:
2209 case LTTNG_KERNEL_KRETPROBE:
2210 (*events)[i].type = LTTNG_EVENT_PROBE;
2211 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2212 sizeof(struct lttng_kernel_kprobe));
2213 break;
2214 case LTTNG_KERNEL_FUNCTION:
2215 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2216 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2217 sizeof(struct lttng_kernel_function));
2218 break;
2219 case LTTNG_KERNEL_NOOP:
2220 (*events)[i].type = LTTNG_EVENT_NOOP;
2221 break;
2222 case LTTNG_KERNEL_SYSCALL:
2223 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2224 break;
2225 case LTTNG_KERNEL_ALL:
2226 assert(0);
2227 break;
2228 }
2229 i++;
2230 }
2231
2232 return nb_event;
2233
2234 error:
2235 return ret;
2236 }
2237
2238 /*
2239 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2240 */
2241 static int cmd_disable_channel(struct ltt_session *session,
2242 int domain, char *channel_name)
2243 {
2244 int ret;
2245 struct ltt_ust_session *usess;
2246
2247 usess = session->ust_session;
2248
2249 switch (domain) {
2250 case LTTNG_DOMAIN_KERNEL:
2251 {
2252 ret = channel_kernel_disable(session->kernel_session,
2253 channel_name);
2254 if (ret != LTTCOMM_OK) {
2255 goto error;
2256 }
2257
2258 kernel_wait_quiescent(kernel_tracer_fd);
2259 break;
2260 }
2261 case LTTNG_DOMAIN_UST:
2262 {
2263 struct ltt_ust_channel *uchan;
2264 struct lttng_ht *chan_ht;
2265
2266 chan_ht = usess->domain_global.channels;
2267
2268 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2269 if (uchan == NULL) {
2270 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2271 goto error;
2272 }
2273
2274 ret = channel_ust_disable(usess, domain, uchan);
2275 if (ret != LTTCOMM_OK) {
2276 goto error;
2277 }
2278 break;
2279 }
2280 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2281 case LTTNG_DOMAIN_UST_EXEC_NAME:
2282 case LTTNG_DOMAIN_UST_PID:
2283 ret = LTTCOMM_NOT_IMPLEMENTED;
2284 goto error;
2285 default:
2286 ret = LTTCOMM_UNKNOWN_DOMAIN;
2287 goto error;
2288 }
2289
2290 ret = LTTCOMM_OK;
2291
2292 error:
2293 return ret;
2294 }
2295
2296 /*
2297 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2298 */
2299 static int cmd_enable_channel(struct ltt_session *session,
2300 int domain, struct lttng_channel *attr)
2301 {
2302 int ret;
2303 struct ltt_ust_session *usess = session->ust_session;
2304 struct lttng_ht *chan_ht;
2305
2306 DBG("Enabling channel %s for session %s", attr->name, session->name);
2307
2308 switch (domain) {
2309 case LTTNG_DOMAIN_KERNEL:
2310 {
2311 struct ltt_kernel_channel *kchan;
2312
2313 kchan = trace_kernel_get_channel_by_name(attr->name,
2314 session->kernel_session);
2315 if (kchan == NULL) {
2316 ret = channel_kernel_create(session->kernel_session,
2317 attr, kernel_poll_pipe[1]);
2318 } else {
2319 ret = channel_kernel_enable(session->kernel_session, kchan);
2320 }
2321
2322 if (ret != LTTCOMM_OK) {
2323 goto error;
2324 }
2325
2326 kernel_wait_quiescent(kernel_tracer_fd);
2327 break;
2328 }
2329 case LTTNG_DOMAIN_UST:
2330 {
2331 struct ltt_ust_channel *uchan;
2332
2333 chan_ht = usess->domain_global.channels;
2334
2335 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2336 if (uchan == NULL) {
2337 ret = channel_ust_create(usess, domain, attr);
2338 } else {
2339 ret = channel_ust_enable(usess, domain, uchan);
2340 }
2341 break;
2342 }
2343 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2344 case LTTNG_DOMAIN_UST_EXEC_NAME:
2345 case LTTNG_DOMAIN_UST_PID:
2346 ret = LTTCOMM_NOT_IMPLEMENTED;
2347 goto error;
2348 default:
2349 ret = LTTCOMM_UNKNOWN_DOMAIN;
2350 goto error;
2351 }
2352
2353 error:
2354 return ret;
2355 }
2356
2357 /*
2358 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2359 */
2360 static int cmd_disable_event(struct ltt_session *session, int domain,
2361 char *channel_name, char *event_name)
2362 {
2363 int ret;
2364
2365 switch (domain) {
2366 case LTTNG_DOMAIN_KERNEL:
2367 {
2368 struct ltt_kernel_channel *kchan;
2369 struct ltt_kernel_session *ksess;
2370
2371 ksess = session->kernel_session;
2372
2373 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2374 if (kchan == NULL) {
2375 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2376 goto error;
2377 }
2378
2379 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2380 if (ret != LTTCOMM_OK) {
2381 goto error;
2382 }
2383
2384 kernel_wait_quiescent(kernel_tracer_fd);
2385 break;
2386 }
2387 case LTTNG_DOMAIN_UST:
2388 {
2389 struct ltt_ust_channel *uchan;
2390 struct ltt_ust_session *usess;
2391
2392 usess = session->ust_session;
2393
2394 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2395 channel_name);
2396 if (uchan == NULL) {
2397 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2398 goto error;
2399 }
2400
2401 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2402 if (ret != LTTCOMM_OK) {
2403 goto error;
2404 }
2405
2406 DBG3("Disable UST event %s in channel %s completed", event_name,
2407 channel_name);
2408 break;
2409 }
2410 case LTTNG_DOMAIN_UST_EXEC_NAME:
2411 case LTTNG_DOMAIN_UST_PID:
2412 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2413 default:
2414 ret = LTTCOMM_NOT_IMPLEMENTED;
2415 goto error;
2416 }
2417
2418 ret = LTTCOMM_OK;
2419
2420 error:
2421 return ret;
2422 }
2423
2424 /*
2425 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2426 */
2427 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2428 char *channel_name)
2429 {
2430 int ret;
2431
2432 switch (domain) {
2433 case LTTNG_DOMAIN_KERNEL:
2434 {
2435 struct ltt_kernel_session *ksess;
2436 struct ltt_kernel_channel *kchan;
2437
2438 ksess = session->kernel_session;
2439
2440 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2441 if (kchan == NULL) {
2442 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2443 goto error;
2444 }
2445
2446 ret = event_kernel_disable_all(ksess, kchan);
2447 if (ret != LTTCOMM_OK) {
2448 goto error;
2449 }
2450
2451 kernel_wait_quiescent(kernel_tracer_fd);
2452 break;
2453 }
2454 case LTTNG_DOMAIN_UST:
2455 {
2456 struct ltt_ust_session *usess;
2457 struct ltt_ust_channel *uchan;
2458
2459 usess = session->ust_session;
2460
2461 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2462 channel_name);
2463 if (uchan == NULL) {
2464 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2465 goto error;
2466 }
2467
2468 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2469 if (ret != 0) {
2470 goto error;
2471 }
2472
2473 DBG3("Disable all UST events in channel %s completed", channel_name);
2474
2475 break;
2476 }
2477 case LTTNG_DOMAIN_UST_EXEC_NAME:
2478 case LTTNG_DOMAIN_UST_PID:
2479 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2480 default:
2481 ret = LTTCOMM_NOT_IMPLEMENTED;
2482 goto error;
2483 }
2484
2485 ret = LTTCOMM_OK;
2486
2487 error:
2488 return ret;
2489 }
2490
2491 /*
2492 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2493 */
2494 static int cmd_add_context(struct ltt_session *session, int domain,
2495 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2496 {
2497 int ret;
2498
2499 switch (domain) {
2500 case LTTNG_DOMAIN_KERNEL:
2501 /* Add kernel context to kernel tracer */
2502 ret = context_kernel_add(session->kernel_session, ctx,
2503 event_name, channel_name);
2504 if (ret != LTTCOMM_OK) {
2505 goto error;
2506 }
2507 break;
2508 case LTTNG_DOMAIN_UST:
2509 {
2510 struct ltt_ust_session *usess = session->ust_session;
2511
2512 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2513 if (ret != LTTCOMM_OK) {
2514 goto error;
2515 }
2516 break;
2517 }
2518 case LTTNG_DOMAIN_UST_EXEC_NAME:
2519 case LTTNG_DOMAIN_UST_PID:
2520 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2521 default:
2522 ret = LTTCOMM_NOT_IMPLEMENTED;
2523 goto error;
2524 }
2525
2526 ret = LTTCOMM_OK;
2527
2528 error:
2529 return ret;
2530 }
2531
2532 /*
2533 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2534 *
2535 * TODO: currently, both events and loglevels are kept within the same
2536 * namespace for UST global registry/app registery, so if an event
2537 * happen to have the same name as the loglevel (very unlikely though),
2538 * and an attempt is made to enable/disable both in the same session,
2539 * the first to be created will be the only one allowed to exist.
2540 */
2541 static int cmd_enable_event(struct ltt_session *session, int domain,
2542 char *channel_name, struct lttng_event *event)
2543 {
2544 int ret;
2545 struct lttng_channel *attr;
2546 struct ltt_ust_session *usess = session->ust_session;
2547
2548 switch (domain) {
2549 case LTTNG_DOMAIN_KERNEL:
2550 {
2551 struct ltt_kernel_channel *kchan;
2552
2553 kchan = trace_kernel_get_channel_by_name(channel_name,
2554 session->kernel_session);
2555 if (kchan == NULL) {
2556 attr = channel_new_default_attr(domain);
2557 if (attr == NULL) {
2558 ret = LTTCOMM_FATAL;
2559 goto error;
2560 }
2561 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2562
2563 /* This call will notify the kernel thread */
2564 ret = channel_kernel_create(session->kernel_session,
2565 attr, kernel_poll_pipe[1]);
2566 if (ret != LTTCOMM_OK) {
2567 free(attr);
2568 goto error;
2569 }
2570 free(attr);
2571 }
2572
2573 /* Get the newly created kernel channel pointer */
2574 kchan = trace_kernel_get_channel_by_name(channel_name,
2575 session->kernel_session);
2576 if (kchan == NULL) {
2577 /* This sould not happen... */
2578 ret = LTTCOMM_FATAL;
2579 goto error;
2580 }
2581
2582 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2583 event);
2584 if (ret != LTTCOMM_OK) {
2585 goto error;
2586 }
2587
2588 kernel_wait_quiescent(kernel_tracer_fd);
2589 break;
2590 }
2591 case LTTNG_DOMAIN_UST:
2592 {
2593 struct lttng_channel *attr;
2594 struct ltt_ust_channel *uchan;
2595
2596 /* Get channel from global UST domain */
2597 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2598 channel_name);
2599 if (uchan == NULL) {
2600 /* Create default channel */
2601 attr = channel_new_default_attr(domain);
2602 if (attr == NULL) {
2603 ret = LTTCOMM_FATAL;
2604 goto error;
2605 }
2606 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2607 attr->name[NAME_MAX - 1] = '\0';
2608
2609 ret = channel_ust_create(usess, domain, attr);
2610 if (ret != LTTCOMM_OK) {
2611 free(attr);
2612 goto error;
2613 }
2614 free(attr);
2615
2616 /* Get the newly created channel reference back */
2617 uchan = trace_ust_find_channel_by_name(
2618 usess->domain_global.channels, channel_name);
2619 if (uchan == NULL) {
2620 /* Something is really wrong */
2621 ret = LTTCOMM_FATAL;
2622 goto error;
2623 }
2624 }
2625
2626 /* At this point, the session and channel exist on the tracer */
2627 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2628 if (ret != LTTCOMM_OK) {
2629 goto error;
2630 }
2631 break;
2632 }
2633 case LTTNG_DOMAIN_UST_EXEC_NAME:
2634 case LTTNG_DOMAIN_UST_PID:
2635 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2636 default:
2637 ret = LTTCOMM_NOT_IMPLEMENTED;
2638 goto error;
2639 }
2640
2641 ret = LTTCOMM_OK;
2642
2643 error:
2644 return ret;
2645 }
2646
2647 /*
2648 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2649 */
2650 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2651 char *channel_name, int event_type)
2652 {
2653 int ret;
2654 struct ltt_kernel_channel *kchan;
2655
2656 switch (domain) {
2657 case LTTNG_DOMAIN_KERNEL:
2658 kchan = trace_kernel_get_channel_by_name(channel_name,
2659 session->kernel_session);
2660 if (kchan == NULL) {
2661 /* This call will notify the kernel thread */
2662 ret = channel_kernel_create(session->kernel_session, NULL,
2663 kernel_poll_pipe[1]);
2664 if (ret != LTTCOMM_OK) {
2665 goto error;
2666 }
2667
2668 /* Get the newly created kernel channel pointer */
2669 kchan = trace_kernel_get_channel_by_name(channel_name,
2670 session->kernel_session);
2671 if (kchan == NULL) {
2672 /* This sould not happen... */
2673 ret = LTTCOMM_FATAL;
2674 goto error;
2675 }
2676
2677 }
2678
2679 switch (event_type) {
2680 case LTTNG_EVENT_SYSCALL:
2681 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2682 kchan, kernel_tracer_fd);
2683 break;
2684 case LTTNG_EVENT_TRACEPOINT:
2685 /*
2686 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2687 * events already registered to the channel.
2688 */
2689 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2690 kchan, kernel_tracer_fd);
2691 break;
2692 case LTTNG_EVENT_ALL:
2693 /* Enable syscalls and tracepoints */
2694 ret = event_kernel_enable_all(session->kernel_session,
2695 kchan, kernel_tracer_fd);
2696 break;
2697 default:
2698 ret = LTTCOMM_KERN_ENABLE_FAIL;
2699 goto error;
2700 }
2701
2702 /* Manage return value */
2703 if (ret != LTTCOMM_OK) {
2704 goto error;
2705 }
2706
2707 kernel_wait_quiescent(kernel_tracer_fd);
2708 break;
2709 case LTTNG_DOMAIN_UST:
2710 {
2711 struct lttng_channel *attr;
2712 struct ltt_ust_channel *uchan;
2713 struct ltt_ust_session *usess = session->ust_session;
2714
2715 /* Get channel from global UST domain */
2716 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2717 channel_name);
2718 if (uchan == NULL) {
2719 /* Create default channel */
2720 attr = channel_new_default_attr(domain);
2721 if (attr == NULL) {
2722 ret = LTTCOMM_FATAL;
2723 goto error;
2724 }
2725 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2726 attr->name[NAME_MAX - 1] = '\0';
2727
2728 /* Use the internal command enable channel */
2729 ret = channel_ust_create(usess, domain, attr);
2730 if (ret != LTTCOMM_OK) {
2731 free(attr);
2732 goto error;
2733 }
2734 free(attr);
2735
2736 /* Get the newly created channel reference back */
2737 uchan = trace_ust_find_channel_by_name(
2738 usess->domain_global.channels, channel_name);
2739 if (uchan == NULL) {
2740 /* Something is really wrong */
2741 ret = LTTCOMM_FATAL;
2742 goto error;
2743 }
2744 }
2745
2746 /* At this point, the session and channel exist on the tracer */
2747
2748 switch (event_type) {
2749 case LTTNG_EVENT_ALL:
2750 case LTTNG_EVENT_TRACEPOINT:
2751 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2752 if (ret != LTTCOMM_OK) {
2753 goto error;
2754 }
2755 break;
2756 default:
2757 ret = LTTCOMM_UST_ENABLE_FAIL;
2758 goto error;
2759 }
2760
2761 /* Manage return value */
2762 if (ret != LTTCOMM_OK) {
2763 goto error;
2764 }
2765
2766 break;
2767 }
2768 case LTTNG_DOMAIN_UST_EXEC_NAME:
2769 case LTTNG_DOMAIN_UST_PID:
2770 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2771 default:
2772 ret = LTTCOMM_NOT_IMPLEMENTED;
2773 goto error;
2774 }
2775
2776 ret = LTTCOMM_OK;
2777
2778 error:
2779 return ret;
2780 }
2781
2782 /*
2783 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2784 */
2785 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2786 {
2787 int ret;
2788 ssize_t nb_events = 0;
2789
2790 switch (domain) {
2791 case LTTNG_DOMAIN_KERNEL:
2792 nb_events = kernel_list_events(kernel_tracer_fd, events);
2793 if (nb_events < 0) {
2794 ret = LTTCOMM_KERN_LIST_FAIL;
2795 goto error;
2796 }
2797 break;
2798 case LTTNG_DOMAIN_UST:
2799 nb_events = ust_app_list_events(events);
2800 if (nb_events < 0) {
2801 ret = LTTCOMM_UST_LIST_FAIL;
2802 goto error;
2803 }
2804 break;
2805 default:
2806 ret = LTTCOMM_NOT_IMPLEMENTED;
2807 goto error;
2808 }
2809
2810 return nb_events;
2811
2812 error:
2813 /* Return negative value to differentiate return code */
2814 return -ret;
2815 }
2816
2817 /*
2818 * Command LTTNG_START_TRACE processed by the client thread.
2819 */
2820 static int cmd_start_trace(struct ltt_session *session)
2821 {
2822 int ret;
2823 struct ltt_kernel_session *ksession;
2824 struct ltt_ust_session *usess;
2825
2826 /* Short cut */
2827 ksession = session->kernel_session;
2828 usess = session->ust_session;
2829
2830 if (session->enabled) {
2831 ret = LTTCOMM_UST_START_FAIL;
2832 goto error;
2833 }
2834
2835 session->enabled = 1;
2836
2837 /* Kernel tracing */
2838 if (ksession != NULL) {
2839 struct ltt_kernel_channel *kchan;
2840
2841 /* Open kernel metadata */
2842 if (ksession->metadata == NULL) {
2843 ret = kernel_open_metadata(ksession, ksession->trace_path);
2844 if (ret < 0) {
2845 ret = LTTCOMM_KERN_META_FAIL;
2846 goto error;
2847 }
2848 }
2849
2850 /* Open kernel metadata stream */
2851 if (ksession->metadata_stream_fd == 0) {
2852 ret = kernel_open_metadata_stream(ksession);
2853 if (ret < 0) {
2854 ERR("Kernel create metadata stream failed");
2855 ret = LTTCOMM_KERN_STREAM_FAIL;
2856 goto error;
2857 }
2858 }
2859
2860 /* For each channel */
2861 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2862 if (kchan->stream_count == 0) {
2863 ret = kernel_open_channel_stream(kchan);
2864 if (ret < 0) {
2865 ret = LTTCOMM_KERN_STREAM_FAIL;
2866 goto error;
2867 }
2868 /* Update the stream global counter */
2869 ksession->stream_count_global += ret;
2870 }
2871 }
2872
2873 /* Setup kernel consumer socket and send fds to it */
2874 ret = init_kernel_tracing(ksession);
2875 if (ret < 0) {
2876 ret = LTTCOMM_KERN_START_FAIL;
2877 goto error;
2878 }
2879
2880 /* This start the kernel tracing */
2881 ret = kernel_start_session(ksession);
2882 if (ret < 0) {
2883 ret = LTTCOMM_KERN_START_FAIL;
2884 goto error;
2885 }
2886
2887 /* Quiescent wait after starting trace */
2888 kernel_wait_quiescent(kernel_tracer_fd);
2889 }
2890
2891 /* Flag session that trace should start automatically */
2892 if (usess) {
2893 usess->start_trace = 1;
2894
2895 ret = ust_app_start_trace_all(usess);
2896 if (ret < 0) {
2897 ret = LTTCOMM_UST_START_FAIL;
2898 goto error;
2899 }
2900 }
2901
2902 ret = LTTCOMM_OK;
2903
2904 error:
2905 return ret;
2906 }
2907
2908 /*
2909 * Command LTTNG_STOP_TRACE processed by the client thread.
2910 */
2911 static int cmd_stop_trace(struct ltt_session *session)
2912 {
2913 int ret;
2914 struct ltt_kernel_channel *kchan;
2915 struct ltt_kernel_session *ksession;
2916 struct ltt_ust_session *usess;
2917
2918 /* Short cut */
2919 ksession = session->kernel_session;
2920 usess = session->ust_session;
2921
2922 if (!session->enabled) {
2923 ret = LTTCOMM_UST_STOP_FAIL;
2924 goto error;
2925 }
2926
2927 session->enabled = 0;
2928
2929 /* Kernel tracer */
2930 if (ksession != NULL) {
2931 DBG("Stop kernel tracing");
2932
2933 /* Flush all buffers before stopping */
2934 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2935 if (ret < 0) {
2936 ERR("Kernel metadata flush failed");
2937 }
2938
2939 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2940 ret = kernel_flush_buffer(kchan);
2941 if (ret < 0) {
2942 ERR("Kernel flush buffer error");
2943 }
2944 }
2945
2946 ret = kernel_stop_session(ksession);
2947 if (ret < 0) {
2948 ret = LTTCOMM_KERN_STOP_FAIL;
2949 goto error;
2950 }
2951
2952 kernel_wait_quiescent(kernel_tracer_fd);
2953 }
2954
2955 if (usess) {
2956 usess->start_trace = 0;
2957
2958 ret = ust_app_stop_trace_all(usess);
2959 if (ret < 0) {
2960 ret = LTTCOMM_UST_STOP_FAIL;
2961 goto error;
2962 }
2963 }
2964
2965 ret = LTTCOMM_OK;
2966
2967 error:
2968 return ret;
2969 }
2970
2971 /*
2972 * Command LTTNG_CREATE_SESSION processed by the client thread.
2973 */
2974 static int cmd_create_session(char *name, char *path, struct ucred *creds)
2975 {
2976 int ret;
2977
2978 ret = session_create(name, path, creds->uid, creds->gid);
2979 if (ret != LTTCOMM_OK) {
2980 goto error;
2981 }
2982
2983 ret = LTTCOMM_OK;
2984
2985 error:
2986 return ret;
2987 }
2988
2989 /*
2990 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2991 */
2992 static int cmd_destroy_session(struct ltt_session *session, char *name)
2993 {
2994 int ret;
2995
2996 /* Clean kernel session teardown */
2997 teardown_kernel_session(session);
2998 /* UST session teardown */
2999 teardown_ust_session(session);
3000
3001 /*
3002 * Must notify the kernel thread here to update it's poll setin order
3003 * to remove the channel(s)' fd just destroyed.
3004 */
3005 ret = notify_thread_pipe(kernel_poll_pipe[1]);
3006 if (ret < 0) {
3007 perror("write kernel poll pipe");
3008 }
3009
3010 ret = session_destroy(session);
3011
3012 return ret;
3013 }
3014
3015 /*
3016 * Command LTTNG_CALIBRATE processed by the client thread.
3017 */
3018 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3019 {
3020 int ret;
3021
3022 switch (domain) {
3023 case LTTNG_DOMAIN_KERNEL:
3024 {
3025 struct lttng_kernel_calibrate kcalibrate;
3026
3027 kcalibrate.type = calibrate->type;
3028 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3029 if (ret < 0) {
3030 ret = LTTCOMM_KERN_ENABLE_FAIL;
3031 goto error;
3032 }
3033 break;
3034 }
3035 default:
3036 /* TODO: Userspace tracing */
3037 ret = LTTCOMM_NOT_IMPLEMENTED;
3038 goto error;
3039 }
3040
3041 ret = LTTCOMM_OK;
3042
3043 error:
3044 return ret;
3045 }
3046
3047 /*
3048 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3049 */
3050 static int cmd_register_consumer(struct ltt_session *session, int domain,
3051 char *sock_path)
3052 {
3053 int ret, sock;
3054
3055 switch (domain) {
3056 case LTTNG_DOMAIN_KERNEL:
3057 /* Can't register a consumer if there is already one */
3058 if (session->kernel_session->consumer_fds_sent != 0) {
3059 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3060 goto error;
3061 }
3062
3063 sock = lttcomm_connect_unix_sock(sock_path);
3064 if (sock < 0) {
3065 ret = LTTCOMM_CONNECT_FAIL;
3066 goto error;
3067 }
3068
3069 session->kernel_session->consumer_fd = sock;
3070 break;
3071 default:
3072 /* TODO: Userspace tracing */
3073 ret = LTTCOMM_NOT_IMPLEMENTED;
3074 goto error;
3075 }
3076
3077 ret = LTTCOMM_OK;
3078
3079 error:
3080 return ret;
3081 }
3082
3083 /*
3084 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3085 */
3086 static ssize_t cmd_list_domains(struct ltt_session *session,
3087 struct lttng_domain **domains)
3088 {
3089 int ret, index = 0;
3090 ssize_t nb_dom = 0;
3091
3092 if (session->kernel_session != NULL) {
3093 DBG3("Listing domains found kernel domain");
3094 nb_dom++;
3095 }
3096
3097 if (session->ust_session != NULL) {
3098 DBG3("Listing domains found UST global domain");
3099 nb_dom++;
3100 }
3101
3102 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3103 if (*domains == NULL) {
3104 ret = -LTTCOMM_FATAL;
3105 goto error;
3106 }
3107
3108 if (session->kernel_session != NULL) {
3109 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3110 index++;
3111 }
3112
3113 if (session->ust_session != NULL) {
3114 (*domains)[index].type = LTTNG_DOMAIN_UST;
3115 index++;
3116 }
3117
3118 return nb_dom;
3119
3120 error:
3121 return ret;
3122 }
3123
3124 /*
3125 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3126 */
3127 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3128 struct lttng_channel **channels)
3129 {
3130 int ret;
3131 ssize_t nb_chan = 0;
3132
3133 switch (domain) {
3134 case LTTNG_DOMAIN_KERNEL:
3135 if (session->kernel_session != NULL) {
3136 nb_chan = session->kernel_session->channel_count;
3137 }
3138 DBG3("Number of kernel channels %zd", nb_chan);
3139 break;
3140 case LTTNG_DOMAIN_UST:
3141 if (session->ust_session != NULL) {
3142 nb_chan = lttng_ht_get_count(
3143 session->ust_session->domain_global.channels);
3144 }
3145 DBG3("Number of UST global channels %zd", nb_chan);
3146 break;
3147 default:
3148 *channels = NULL;
3149 ret = -LTTCOMM_NOT_IMPLEMENTED;
3150 goto error;
3151 }
3152
3153 if (nb_chan > 0) {
3154 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3155 if (*channels == NULL) {
3156 ret = -LTTCOMM_FATAL;
3157 goto error;
3158 }
3159
3160 list_lttng_channels(domain, session, *channels);
3161 } else {
3162 *channels = NULL;
3163 }
3164
3165 return nb_chan;
3166
3167 error:
3168 return ret;
3169 }
3170
3171 /*
3172 * Command LTTNG_LIST_EVENTS processed by the client thread.
3173 */
3174 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3175 char *channel_name, struct lttng_event **events)
3176 {
3177 int ret = 0;
3178 ssize_t nb_event = 0;
3179
3180 switch (domain) {
3181 case LTTNG_DOMAIN_KERNEL:
3182 if (session->kernel_session != NULL) {
3183 nb_event = list_lttng_kernel_events(channel_name,
3184 session->kernel_session, events);
3185 }
3186 break;
3187 case LTTNG_DOMAIN_UST:
3188 {
3189 if (session->ust_session != NULL) {
3190 nb_event = list_lttng_ust_global_events(channel_name,
3191 &session->ust_session->domain_global, events);
3192 }
3193 break;
3194 }
3195 default:
3196 ret = -LTTCOMM_NOT_IMPLEMENTED;
3197 goto error;
3198 }
3199
3200 ret = nb_event;
3201
3202 error:
3203 return ret;
3204 }
3205
3206 /*
3207 * Process the command requested by the lttng client within the command
3208 * context structure. This function make sure that the return structure (llm)
3209 * is set and ready for transmission before returning.
3210 *
3211 * Return any error encountered or 0 for success.
3212 */
3213 static int process_client_msg(struct command_ctx *cmd_ctx)
3214 {
3215 int ret = LTTCOMM_OK;
3216 int need_tracing_session = 1;
3217
3218 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3219
3220 if (opt_no_kernel && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
3221 ret = LTTCOMM_KERN_NA;
3222 goto error;
3223 }
3224
3225 /*
3226 * Check for command that don't needs to allocate a returned payload. We do
3227 * this here so we don't have to make the call for no payload at each
3228 * command.
3229 */
3230 switch(cmd_ctx->lsm->cmd_type) {
3231 case LTTNG_LIST_SESSIONS:
3232 case LTTNG_LIST_TRACEPOINTS:
3233 case LTTNG_LIST_DOMAINS:
3234 case LTTNG_LIST_CHANNELS:
3235 case LTTNG_LIST_EVENTS:
3236 break;
3237 default:
3238 /* Setup lttng message with no payload */
3239 ret = setup_lttng_msg(cmd_ctx, 0);
3240 if (ret < 0) {
3241 /* This label does not try to unlock the session */
3242 goto init_setup_error;
3243 }
3244 }
3245
3246 /* Commands that DO NOT need a session. */
3247 switch (cmd_ctx->lsm->cmd_type) {
3248 case LTTNG_CALIBRATE:
3249 case LTTNG_CREATE_SESSION:
3250 case LTTNG_LIST_SESSIONS:
3251 case LTTNG_LIST_TRACEPOINTS:
3252 need_tracing_session = 0;
3253 break;
3254 default:
3255 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3256 session_lock_list();
3257 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3258 session_unlock_list();
3259 if (cmd_ctx->session == NULL) {
3260 if (cmd_ctx->lsm->session.name != NULL) {
3261 ret = LTTCOMM_SESS_NOT_FOUND;
3262 } else {
3263 /* If no session name specified */
3264 ret = LTTCOMM_SELECT_SESS;
3265 }
3266 goto error;
3267 } else {
3268 /* Acquire lock for the session */
3269 session_lock(cmd_ctx->session);
3270 }
3271 break;
3272 }
3273
3274 /*
3275 * Check domain type for specific "pre-action".
3276 */
3277 switch (cmd_ctx->lsm->domain.type) {
3278 case LTTNG_DOMAIN_KERNEL:
3279 /* Kernel tracer check */
3280 if (kernel_tracer_fd == 0) {
3281 /* Basically, load kernel tracer modules */
3282 init_kernel_tracer();
3283 if (kernel_tracer_fd == 0) {
3284 ret = LTTCOMM_KERN_NA;
3285 goto error;
3286 }
3287 }
3288
3289 /* Need a session for kernel command */
3290 if (need_tracing_session) {
3291 if (cmd_ctx->session->kernel_session == NULL) {
3292 ret = create_kernel_session(cmd_ctx->session);
3293 if (ret < 0) {
3294 ret = LTTCOMM_KERN_SESS_FAIL;
3295 goto error;
3296 }
3297 }
3298
3299 /* Start the kernel consumer daemon */
3300 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3301 if (kconsumer_data.pid == 0 &&
3302 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3303 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3304 ret = start_consumerd(&kconsumer_data);
3305 if (ret < 0) {
3306 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3307 goto error;
3308 }
3309 } else {
3310 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3311 }
3312 }
3313 break;
3314 case LTTNG_DOMAIN_UST:
3315 {
3316 if (need_tracing_session) {
3317 if (cmd_ctx->session->ust_session == NULL) {
3318 ret = create_ust_session(cmd_ctx->session,
3319 &cmd_ctx->lsm->domain);
3320 if (ret != LTTCOMM_OK) {
3321 goto error;
3322 }
3323 }
3324 /* Start the UST consumer daemons */
3325 /* 64-bit */
3326 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3327 if (consumerd64_bin[0] != '\0' &&
3328 ustconsumer64_data.pid == 0 &&
3329 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3330 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3331 ret = start_consumerd(&ustconsumer64_data);
3332 if (ret < 0) {
3333 ret = LTTCOMM_UST_CONSUMER64_FAIL;