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lttng-sessiond: do not call ustctl_register_done()
[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 <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 =
178 __stringify(CONFIG_CONSUMERD32_BIN);
179 static const char *consumerd64_bin =
180 __stringify(CONFIG_CONSUMERD64_BIN);
181 static const char *consumerd32_libdir =
182 __stringify(CONFIG_CONSUMERD32_LIBDIR);
183 static const char *consumerd64_libdir =
184 __stringify(CONFIG_CONSUMERD64_LIBDIR);
185
186 static
187 void setup_consumerd_path(void)
188 {
189 const char *bin, *libdir;
190
191 /*
192 * Allow INSTALL_BIN_PATH to be used as a target path for the
193 * native architecture size consumer if CONFIG_CONSUMER*_PATH
194 * has not been defined.
195 */
196 #if (CAA_BITS_PER_LONG == 32)
197 if (!consumerd32_bin[0]) {
198 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
199 }
200 if (!consumerd32_libdir[0]) {
201 consumerd32_libdir = INSTALL_LIB_PATH;
202 }
203 #elif (CAA_BITS_PER_LONG == 64)
204 if (!consumerd64_bin[0]) {
205 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
206 }
207 if (!consumerd64_libdir[0]) {
208 consumerd64_libdir = INSTALL_LIB_PATH;
209 }
210 #else
211 #error "Unknown bitness"
212 #endif
213
214 /*
215 * runtime env. var. overrides the build default.
216 */
217 bin = getenv("LTTNG_CONSUMERD32_BIN");
218 if (bin) {
219 consumerd32_bin = bin;
220 }
221 bin = getenv("LTTNG_CONSUMERD64_BIN");
222 if (bin) {
223 consumerd64_bin = bin;
224 }
225 libdir = getenv("LTTNG_TOOLS_CONSUMERD32_LIBDIR");
226 if (libdir) {
227 consumerd32_libdir = libdir;
228 }
229 libdir = getenv("LTTNG_TOOLS_CONSUMERD64_LIBDIR");
230 if (libdir) {
231 consumerd64_libdir = libdir;
232 }
233 }
234
235 /*
236 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
237 */
238 static int create_thread_poll_set(struct lttng_poll_event *events,
239 unsigned int size)
240 {
241 int ret;
242
243 if (events == NULL || size == 0) {
244 ret = -1;
245 goto error;
246 }
247
248 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
249 if (ret < 0) {
250 goto error;
251 }
252
253 /* Add quit pipe */
254 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
255 if (ret < 0) {
256 goto error;
257 }
258
259 return 0;
260
261 error:
262 return ret;
263 }
264
265 /*
266 * Check if the thread quit pipe was triggered.
267 *
268 * Return 1 if it was triggered else 0;
269 */
270 static int check_thread_quit_pipe(int fd, uint32_t events)
271 {
272 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
273 return 1;
274 }
275
276 return 0;
277 }
278
279 /*
280 * Remove modules in reverse load order.
281 */
282 static int modprobe_remove_kernel_modules(void)
283 {
284 int ret = 0, i;
285 char modprobe[256];
286
287 for (i = ARRAY_SIZE(kernel_modules_list) - 1; i >= 0; i--) {
288 ret = snprintf(modprobe, sizeof(modprobe),
289 "/sbin/modprobe -r -q %s",
290 kernel_modules_list[i].name);
291 if (ret < 0) {
292 perror("snprintf modprobe -r");
293 goto error;
294 }
295 modprobe[sizeof(modprobe) - 1] = '\0';
296 ret = system(modprobe);
297 if (ret == -1) {
298 ERR("Unable to launch modprobe -r for module %s",
299 kernel_modules_list[i].name);
300 } else if (kernel_modules_list[i].required
301 && WEXITSTATUS(ret) != 0) {
302 ERR("Unable to remove module %s",
303 kernel_modules_list[i].name);
304 } else {
305 DBG("Modprobe removal successful %s",
306 kernel_modules_list[i].name);
307 }
308 }
309
310 error:
311 return ret;
312 }
313
314 /*
315 * Return group ID of the tracing group or -1 if not found.
316 */
317 static gid_t allowed_group(void)
318 {
319 struct group *grp;
320
321 if (opt_tracing_group) {
322 grp = getgrnam(opt_tracing_group);
323 } else {
324 grp = getgrnam(default_tracing_group);
325 }
326 if (!grp) {
327 return -1;
328 } else {
329 return grp->gr_gid;
330 }
331 }
332
333 /*
334 * Init thread quit pipe.
335 *
336 * Return -1 on error or 0 if all pipes are created.
337 */
338 static int init_thread_quit_pipe(void)
339 {
340 int ret;
341
342 ret = pipe2(thread_quit_pipe, O_CLOEXEC);
343 if (ret < 0) {
344 perror("thread quit pipe");
345 goto error;
346 }
347
348 error:
349 return ret;
350 }
351
352 /*
353 * Complete teardown of a kernel session. This free all data structure related
354 * to a kernel session and update counter.
355 */
356 static void teardown_kernel_session(struct ltt_session *session)
357 {
358 if (!session->kernel_session) {
359 DBG3("No kernel session when tearingdown session");
360 return;
361 }
362
363 DBG("Tearing down kernel session");
364
365 /*
366 * If a custom kernel consumer was registered, close the socket before
367 * tearing down the complete kernel session structure
368 */
369 if (session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
370 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
371 }
372
373 trace_kernel_destroy_session(session->kernel_session);
374 }
375
376 /*
377 * Complete teardown of all UST sessions. This will free everything on his path
378 * and destroy the core essence of all ust sessions :)
379 */
380 static void teardown_ust_session(struct ltt_session *session)
381 {
382 int ret;
383
384 if (!session->ust_session) {
385 DBG3("No UST session when tearingdown session");
386 return;
387 }
388
389 DBG("Tearing down UST session(s)");
390
391 ret = ust_app_destroy_trace_all(session->ust_session);
392 if (ret) {
393 ERR("Error in ust_app_destroy_trace_all");
394 }
395
396 trace_ust_destroy_session(session->ust_session);
397 }
398
399 /*
400 * Stop all threads by closing the thread quit pipe.
401 */
402 static void stop_threads(void)
403 {
404 int ret;
405
406 /* Stopping all threads */
407 DBG("Terminating all threads");
408 ret = notify_thread_pipe(thread_quit_pipe[1]);
409 if (ret < 0) {
410 ERR("write error on thread quit pipe");
411 }
412
413 /* Dispatch thread */
414 dispatch_thread_exit = 1;
415 futex_nto1_wake(&ust_cmd_queue.futex);
416 }
417
418 /*
419 * Cleanup the daemon
420 */
421 static void cleanup(void)
422 {
423 int ret;
424 char *cmd;
425 struct ltt_session *sess, *stmp;
426
427 DBG("Cleaning up");
428
429 DBG("Removing %s directory", rundir);
430 ret = asprintf(&cmd, "rm -rf %s", rundir);
431 if (ret < 0) {
432 ERR("asprintf failed. Something is really wrong!");
433 }
434
435 /* Remove lttng run directory */
436 ret = system(cmd);
437 if (ret < 0) {
438 ERR("Unable to clean %s", rundir);
439 }
440 free(cmd);
441
442 DBG("Cleaning up all session");
443
444 /* Destroy session list mutex */
445 if (session_list_ptr != NULL) {
446 pthread_mutex_destroy(&session_list_ptr->lock);
447
448 /* Cleanup ALL session */
449 cds_list_for_each_entry_safe(sess, stmp,
450 &session_list_ptr->head, list) {
451 teardown_kernel_session(sess);
452 teardown_ust_session(sess);
453 free(sess);
454 }
455 }
456
457 DBG("Closing all UST sockets");
458 ust_app_clean_list();
459
460 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
461
462 if (is_root && !opt_no_kernel) {
463 DBG2("Closing kernel fd");
464 close(kernel_tracer_fd);
465 DBG("Unloading kernel modules");
466 modprobe_remove_kernel_modules();
467 }
468
469 close(thread_quit_pipe[0]);
470 close(thread_quit_pipe[1]);
471
472 /* <fun> */
473 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
474 "Matthew, BEET driven development works!%c[%dm",
475 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
476 /* </fun> */
477 }
478
479 /*
480 * Send data on a unix socket using the liblttsessiondcomm API.
481 *
482 * Return lttcomm error code.
483 */
484 static int send_unix_sock(int sock, void *buf, size_t len)
485 {
486 /* Check valid length */
487 if (len <= 0) {
488 return -1;
489 }
490
491 return lttcomm_send_unix_sock(sock, buf, len);
492 }
493
494 /*
495 * Free memory of a command context structure.
496 */
497 static void clean_command_ctx(struct command_ctx **cmd_ctx)
498 {
499 DBG("Clean command context structure");
500 if (*cmd_ctx) {
501 if ((*cmd_ctx)->llm) {
502 free((*cmd_ctx)->llm);
503 }
504 if ((*cmd_ctx)->lsm) {
505 free((*cmd_ctx)->lsm);
506 }
507 free(*cmd_ctx);
508 *cmd_ctx = NULL;
509 }
510 }
511
512 /*
513 * Send all stream fds of kernel channel to the consumer.
514 */
515 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
516 int sock, struct ltt_kernel_channel *channel,
517 uid_t uid, gid_t gid)
518 {
519 int ret;
520 struct ltt_kernel_stream *stream;
521 struct lttcomm_consumer_msg lkm;
522
523 DBG("Sending streams of channel %s to kernel consumer",
524 channel->channel->name);
525
526 /* Send channel */
527 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
528 lkm.u.channel.channel_key = channel->fd;
529 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
530 lkm.u.channel.mmap_len = 0; /* for kernel */
531 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
532 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
533 if (ret < 0) {
534 perror("send consumer channel");
535 goto error;
536 }
537
538 /* Send streams */
539 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
540 if (!stream->fd) {
541 continue;
542 }
543 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
544 lkm.u.stream.channel_key = channel->fd;
545 lkm.u.stream.stream_key = stream->fd;
546 lkm.u.stream.state = stream->state;
547 lkm.u.stream.output = channel->channel->attr.output;
548 lkm.u.stream.mmap_len = 0; /* for kernel */
549 lkm.u.stream.uid = uid;
550 lkm.u.stream.gid = gid;
551 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
552 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
553 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
554 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
555 if (ret < 0) {
556 perror("send consumer stream");
557 goto error;
558 }
559 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
560 if (ret < 0) {
561 perror("send consumer stream ancillary data");
562 goto error;
563 }
564 }
565
566 DBG("consumer channel streams sent");
567
568 return 0;
569
570 error:
571 return ret;
572 }
573
574 /*
575 * Send all stream fds of the kernel session to the consumer.
576 */
577 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
578 struct ltt_kernel_session *session)
579 {
580 int ret;
581 struct ltt_kernel_channel *chan;
582 struct lttcomm_consumer_msg lkm;
583 int sock = session->consumer_fd;
584
585 DBG("Sending metadata stream fd");
586
587 /* Extra protection. It's NOT supposed to be set to 0 at this point */
588 if (session->consumer_fd == 0) {
589 session->consumer_fd = consumer_data->cmd_sock;
590 }
591
592 if (session->metadata_stream_fd != 0) {
593 /* Send metadata channel fd */
594 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
595 lkm.u.channel.channel_key = session->metadata->fd;
596 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
597 lkm.u.channel.mmap_len = 0; /* for kernel */
598 DBG("Sending metadata channel %d to consumer", lkm.u.stream.stream_key);
599 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
600 if (ret < 0) {
601 perror("send consumer channel");
602 goto error;
603 }
604
605 /* Send metadata stream fd */
606 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
607 lkm.u.stream.channel_key = session->metadata->fd;
608 lkm.u.stream.stream_key = session->metadata_stream_fd;
609 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
610 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
611 lkm.u.stream.mmap_len = 0; /* for kernel */
612 lkm.u.stream.uid = session->uid;
613 lkm.u.stream.gid = session->gid;
614 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
615 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
616 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
617 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
618 if (ret < 0) {
619 perror("send consumer stream");
620 goto error;
621 }
622 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
623 if (ret < 0) {
624 perror("send consumer stream");
625 goto error;
626 }
627 }
628
629 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
630 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
631 session->uid, session->gid);
632 if (ret < 0) {
633 goto error;
634 }
635 }
636
637 DBG("consumer fds (metadata and channel streams) sent");
638
639 return 0;
640
641 error:
642 return ret;
643 }
644
645 /*
646 * Notify UST applications using the shm mmap futex.
647 */
648 static int notify_ust_apps(int active)
649 {
650 char *wait_shm_mmap;
651
652 DBG("Notifying applications of session daemon state: %d", active);
653
654 /* See shm.c for this call implying mmap, shm and futex calls */
655 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
656 if (wait_shm_mmap == NULL) {
657 goto error;
658 }
659
660 /* Wake waiting process */
661 futex_wait_update((int32_t *) wait_shm_mmap, active);
662
663 /* Apps notified successfully */
664 return 0;
665
666 error:
667 return -1;
668 }
669
670 /*
671 * Setup the outgoing data buffer for the response (llm) by allocating the
672 * right amount of memory and copying the original information from the lsm
673 * structure.
674 *
675 * Return total size of the buffer pointed by buf.
676 */
677 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
678 {
679 int ret, buf_size;
680
681 buf_size = size;
682
683 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
684 if (cmd_ctx->llm == NULL) {
685 perror("zmalloc");
686 ret = -ENOMEM;
687 goto error;
688 }
689
690 /* Copy common data */
691 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
692 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
693
694 cmd_ctx->llm->data_size = size;
695 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
696
697 return buf_size;
698
699 error:
700 return ret;
701 }
702
703 /*
704 * Update the kernel poll set of all channel fd available over all tracing
705 * session. Add the wakeup pipe at the end of the set.
706 */
707 static int update_kernel_poll(struct lttng_poll_event *events)
708 {
709 int ret;
710 struct ltt_session *session;
711 struct ltt_kernel_channel *channel;
712
713 DBG("Updating kernel poll set");
714
715 session_lock_list();
716 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
717 session_lock(session);
718 if (session->kernel_session == NULL) {
719 session_unlock(session);
720 continue;
721 }
722
723 cds_list_for_each_entry(channel,
724 &session->kernel_session->channel_list.head, list) {
725 /* Add channel fd to the kernel poll set */
726 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
727 if (ret < 0) {
728 session_unlock(session);
729 goto error;
730 }
731 DBG("Channel fd %d added to kernel set", channel->fd);
732 }
733 session_unlock(session);
734 }
735 session_unlock_list();
736
737 return 0;
738
739 error:
740 session_unlock_list();
741 return -1;
742 }
743
744 /*
745 * Find the channel fd from 'fd' over all tracing session. When found, check
746 * for new channel stream and send those stream fds to the kernel consumer.
747 *
748 * Useful for CPU hotplug feature.
749 */
750 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
751 {
752 int ret = 0;
753 struct ltt_session *session;
754 struct ltt_kernel_channel *channel;
755
756 DBG("Updating kernel streams for channel fd %d", fd);
757
758 session_lock_list();
759 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
760 session_lock(session);
761 if (session->kernel_session == NULL) {
762 session_unlock(session);
763 continue;
764 }
765
766 /* This is not suppose to be 0 but this is an extra security check */
767 if (session->kernel_session->consumer_fd == 0) {
768 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
769 }
770
771 cds_list_for_each_entry(channel,
772 &session->kernel_session->channel_list.head, list) {
773 if (channel->fd == fd) {
774 DBG("Channel found, updating kernel streams");
775 ret = kernel_open_channel_stream(channel);
776 if (ret < 0) {
777 goto error;
778 }
779
780 /*
781 * Have we already sent fds to the consumer? If yes, it means
782 * that tracing is started so it is safe to send our updated
783 * stream fds.
784 */
785 if (session->kernel_session->consumer_fds_sent == 1) {
786 ret = send_kconsumer_channel_streams(consumer_data,
787 session->kernel_session->consumer_fd, channel,
788 session->uid, session->gid);
789 if (ret < 0) {
790 goto error;
791 }
792 }
793 goto error;
794 }
795 }
796 session_unlock(session);
797 }
798 session_unlock_list();
799 return ret;
800
801 error:
802 session_unlock(session);
803 session_unlock_list();
804 return ret;
805 }
806
807 /*
808 * For each tracing session, update newly registered apps.
809 */
810 static void update_ust_app(int app_sock)
811 {
812 struct ltt_session *sess, *stmp;
813
814 /* For all tracing session(s) */
815 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
816 if (sess->ust_session) {
817 ust_app_global_update(sess->ust_session, app_sock);
818 }
819 }
820 }
821
822 /*
823 * This thread manage event coming from the kernel.
824 *
825 * Features supported in this thread:
826 * -) CPU Hotplug
827 */
828 static void *thread_manage_kernel(void *data)
829 {
830 int ret, i, pollfd, update_poll_flag = 1;
831 uint32_t revents, nb_fd;
832 char tmp;
833 struct lttng_poll_event events;
834
835 DBG("Thread manage kernel started");
836
837 ret = create_thread_poll_set(&events, 2);
838 if (ret < 0) {
839 goto error;
840 }
841
842 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
843 if (ret < 0) {
844 goto error;
845 }
846
847 while (1) {
848 if (update_poll_flag == 1) {
849 /*
850 * Reset number of fd in the poll set. Always 2 since there is the thread
851 * quit pipe and the kernel pipe.
852 */
853 events.nb_fd = 2;
854
855 ret = update_kernel_poll(&events);
856 if (ret < 0) {
857 goto error;
858 }
859 update_poll_flag = 0;
860 }
861
862 nb_fd = LTTNG_POLL_GETNB(&events);
863
864 DBG("Thread kernel polling on %d fds", nb_fd);
865
866 /* Zeroed the poll events */
867 lttng_poll_reset(&events);
868
869 /* Poll infinite value of time */
870 ret = lttng_poll_wait(&events, -1);
871 if (ret < 0) {
872 goto error;
873 } else if (ret == 0) {
874 /* Should not happen since timeout is infinite */
875 ERR("Return value of poll is 0 with an infinite timeout.\n"
876 "This should not have happened! Continuing...");
877 continue;
878 }
879
880 for (i = 0; i < nb_fd; i++) {
881 /* Fetch once the poll data */
882 revents = LTTNG_POLL_GETEV(&events, i);
883 pollfd = LTTNG_POLL_GETFD(&events, i);
884
885 /* Thread quit pipe has been closed. Killing thread. */
886 ret = check_thread_quit_pipe(pollfd, revents);
887 if (ret) {
888 goto error;
889 }
890
891 /* Check for data on kernel pipe */
892 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
893 ret = read(kernel_poll_pipe[0], &tmp, 1);
894 update_poll_flag = 1;
895 continue;
896 } else {
897 /*
898 * New CPU detected by the kernel. Adding kernel stream to
899 * kernel session and updating the kernel consumer
900 */
901 if (revents & LPOLLIN) {
902 ret = update_kernel_stream(&kconsumer_data, pollfd);
903 if (ret < 0) {
904 continue;
905 }
906 break;
907 /*
908 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
909 * and unregister kernel stream at this point.
910 */
911 }
912 }
913 }
914 }
915
916 error:
917 DBG("Kernel thread dying");
918 close(kernel_poll_pipe[0]);
919 close(kernel_poll_pipe[1]);
920
921 lttng_poll_clean(&events);
922
923 return NULL;
924 }
925
926 /*
927 * This thread manage the consumer error sent back to the session daemon.
928 */
929 static void *thread_manage_consumer(void *data)
930 {
931 int sock = 0, i, ret, pollfd;
932 uint32_t revents, nb_fd;
933 enum lttcomm_return_code code;
934 struct lttng_poll_event events;
935 struct consumer_data *consumer_data = data;
936
937 DBG("[thread] Manage consumer started");
938
939 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
940 if (ret < 0) {
941 goto error;
942 }
943
944 /*
945 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
946 * Nothing more will be added to this poll set.
947 */
948 ret = create_thread_poll_set(&events, 2);
949 if (ret < 0) {
950 goto error;
951 }
952
953 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
954 if (ret < 0) {
955 goto error;
956 }
957
958 nb_fd = LTTNG_POLL_GETNB(&events);
959
960 /* Inifinite blocking call, waiting for transmission */
961 ret = lttng_poll_wait(&events, -1);
962 if (ret < 0) {
963 goto error;
964 }
965
966 for (i = 0; i < nb_fd; i++) {
967 /* Fetch once the poll data */
968 revents = LTTNG_POLL_GETEV(&events, i);
969 pollfd = LTTNG_POLL_GETFD(&events, i);
970
971 /* Thread quit pipe has been closed. Killing thread. */
972 ret = check_thread_quit_pipe(pollfd, revents);
973 if (ret) {
974 goto error;
975 }
976
977 /* Event on the registration socket */
978 if (pollfd == consumer_data->err_sock) {
979 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
980 ERR("consumer err socket poll error");
981 goto error;
982 }
983 }
984 }
985
986 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
987 if (sock < 0) {
988 goto error;
989 }
990
991 DBG2("Receiving code from consumer err_sock");
992
993 /* Getting status code from kconsumerd */
994 ret = lttcomm_recv_unix_sock(sock, &code,
995 sizeof(enum lttcomm_return_code));
996 if (ret <= 0) {
997 goto error;
998 }
999
1000 if (code == CONSUMERD_COMMAND_SOCK_READY) {
1001 consumer_data->cmd_sock =
1002 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
1003 if (consumer_data->cmd_sock < 0) {
1004 sem_post(&consumer_data->sem);
1005 PERROR("consumer connect");
1006 goto error;
1007 }
1008 /* Signal condition to tell that the kconsumerd is ready */
1009 sem_post(&consumer_data->sem);
1010 DBG("consumer command socket ready");
1011 } else {
1012 ERR("consumer error when waiting for SOCK_READY : %s",
1013 lttcomm_get_readable_code(-code));
1014 goto error;
1015 }
1016
1017 /* Remove the kconsumerd error sock since we've established a connexion */
1018 ret = lttng_poll_del(&events, consumer_data->err_sock);
1019 if (ret < 0) {
1020 goto error;
1021 }
1022
1023 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1024 if (ret < 0) {
1025 goto error;
1026 }
1027
1028 /* Update number of fd */
1029 nb_fd = LTTNG_POLL_GETNB(&events);
1030
1031 /* Inifinite blocking call, waiting for transmission */
1032 ret = lttng_poll_wait(&events, -1);
1033 if (ret < 0) {
1034 goto error;
1035 }
1036
1037 for (i = 0; i < nb_fd; i++) {
1038 /* Fetch once the poll data */
1039 revents = LTTNG_POLL_GETEV(&events, i);
1040 pollfd = LTTNG_POLL_GETFD(&events, i);
1041
1042 /* Thread quit pipe has been closed. Killing thread. */
1043 ret = check_thread_quit_pipe(pollfd, revents);
1044 if (ret) {
1045 goto error;
1046 }
1047
1048 /* Event on the kconsumerd socket */
1049 if (pollfd == sock) {
1050 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1051 ERR("consumer err socket second poll error");
1052 goto error;
1053 }
1054 }
1055 }
1056
1057 /* Wait for any kconsumerd error */
1058 ret = lttcomm_recv_unix_sock(sock, &code,
1059 sizeof(enum lttcomm_return_code));
1060 if (ret <= 0) {
1061 ERR("consumer closed the command socket");
1062 goto error;
1063 }
1064
1065 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1066
1067 error:
1068 DBG("consumer thread dying");
1069 close(consumer_data->err_sock);
1070 close(consumer_data->cmd_sock);
1071 close(sock);
1072
1073 unlink(consumer_data->err_unix_sock_path);
1074 unlink(consumer_data->cmd_unix_sock_path);
1075 consumer_data->pid = 0;
1076
1077 lttng_poll_clean(&events);
1078
1079 return NULL;
1080 }
1081
1082 /*
1083 * This thread manage application communication.
1084 */
1085 static void *thread_manage_apps(void *data)
1086 {
1087 int i, ret, pollfd;
1088 uint32_t revents, nb_fd;
1089 struct ust_command ust_cmd;
1090 struct lttng_poll_event events;
1091
1092 DBG("[thread] Manage application started");
1093
1094 rcu_register_thread();
1095 rcu_thread_online();
1096
1097 ret = create_thread_poll_set(&events, 2);
1098 if (ret < 0) {
1099 goto error;
1100 }
1101
1102 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1103 if (ret < 0) {
1104 goto error;
1105 }
1106
1107 while (1) {
1108 /* Zeroed the events structure */
1109 lttng_poll_reset(&events);
1110
1111 nb_fd = LTTNG_POLL_GETNB(&events);
1112
1113 DBG("Apps thread polling on %d fds", nb_fd);
1114
1115 /* Inifinite blocking call, waiting for transmission */
1116 ret = lttng_poll_wait(&events, -1);
1117 if (ret < 0) {
1118 goto error;
1119 }
1120
1121 for (i = 0; i < nb_fd; i++) {
1122 /* Fetch once the poll data */
1123 revents = LTTNG_POLL_GETEV(&events, i);
1124 pollfd = LTTNG_POLL_GETFD(&events, i);
1125
1126 /* Thread quit pipe has been closed. Killing thread. */
1127 ret = check_thread_quit_pipe(pollfd, revents);
1128 if (ret) {
1129 goto error;
1130 }
1131
1132 /* Inspect the apps cmd pipe */
1133 if (pollfd == apps_cmd_pipe[0]) {
1134 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1135 ERR("Apps command pipe error");
1136 goto error;
1137 } else if (revents & LPOLLIN) {
1138 /* Empty pipe */
1139 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1140 if (ret < 0 || ret < sizeof(ust_cmd)) {
1141 perror("read apps cmd pipe");
1142 goto error;
1143 }
1144
1145 /* Register applicaton to the session daemon */
1146 ret = ust_app_register(&ust_cmd.reg_msg,
1147 ust_cmd.sock);
1148 if (ret == -ENOMEM) {
1149 goto error;
1150 } else if (ret < 0) {
1151 break;
1152 }
1153
1154 /*
1155 * Add channel(s) and event(s) to newly registered apps
1156 * from lttng global UST domain.
1157 */
1158 update_ust_app(ust_cmd.sock);
1159
1160 ret = ust_app_register_done(ust_cmd.sock);
1161 if (ret < 0) {
1162 /*
1163 * If the registration is not possible, we simply
1164 * unregister the apps and continue
1165 */
1166 ust_app_unregister(ust_cmd.sock);
1167 } else {
1168 /*
1169 * We just need here to monitor the close of the UST
1170 * socket and poll set monitor those by default.
1171 */
1172 ret = lttng_poll_add(&events, ust_cmd.sock, 0);
1173 if (ret < 0) {
1174 goto error;
1175 }
1176
1177 DBG("Apps with sock %d added to poll set",
1178 ust_cmd.sock);
1179 }
1180
1181 break;
1182 }
1183 } else {
1184 /*
1185 * At this point, we know that a registered application made
1186 * the event at poll_wait.
1187 */
1188 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1189 /* Removing from the poll set */
1190 ret = lttng_poll_del(&events, pollfd);
1191 if (ret < 0) {
1192 goto error;
1193 }
1194
1195 /* Socket closed on remote end. */
1196 ust_app_unregister(pollfd);
1197 break;
1198 }
1199 }
1200 }
1201 }
1202
1203 error:
1204 DBG("Application communication apps dying");
1205 close(apps_cmd_pipe[0]);
1206 close(apps_cmd_pipe[1]);
1207
1208 lttng_poll_clean(&events);
1209
1210 rcu_thread_offline();
1211 rcu_unregister_thread();
1212 return NULL;
1213 }
1214
1215 /*
1216 * Dispatch request from the registration threads to the application
1217 * communication thread.
1218 */
1219 static void *thread_dispatch_ust_registration(void *data)
1220 {
1221 int ret;
1222 struct cds_wfq_node *node;
1223 struct ust_command *ust_cmd = NULL;
1224
1225 DBG("[thread] Dispatch UST command started");
1226
1227 while (!dispatch_thread_exit) {
1228 /* Atomically prepare the queue futex */
1229 futex_nto1_prepare(&ust_cmd_queue.futex);
1230
1231 do {
1232 /* Dequeue command for registration */
1233 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1234 if (node == NULL) {
1235 DBG("Woken up but nothing in the UST command queue");
1236 /* Continue thread execution */
1237 break;
1238 }
1239
1240 ust_cmd = caa_container_of(node, struct ust_command, node);
1241
1242 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1243 " gid:%d sock:%d name:%s (version %d.%d)",
1244 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1245 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1246 ust_cmd->sock, ust_cmd->reg_msg.name,
1247 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1248 /*
1249 * Inform apps thread of the new application registration. This
1250 * call is blocking so we can be assured that the data will be read
1251 * at some point in time or wait to the end of the world :)
1252 */
1253 ret = write(apps_cmd_pipe[1], ust_cmd,
1254 sizeof(struct ust_command));
1255 if (ret < 0) {
1256 perror("write apps cmd pipe");
1257 if (errno == EBADF) {
1258 /*
1259 * We can't inform the application thread to process
1260 * registration. We will exit or else application
1261 * registration will not occur and tracing will never
1262 * start.
1263 */
1264 goto error;
1265 }
1266 }
1267 free(ust_cmd);
1268 } while (node != NULL);
1269
1270 /* Futex wait on queue. Blocking call on futex() */
1271 futex_nto1_wait(&ust_cmd_queue.futex);
1272 }
1273
1274 error:
1275 DBG("Dispatch thread dying");
1276 return NULL;
1277 }
1278
1279 /*
1280 * This thread manage application registration.
1281 */
1282 static void *thread_registration_apps(void *data)
1283 {
1284 int sock = 0, i, ret, pollfd;
1285 uint32_t revents, nb_fd;
1286 struct lttng_poll_event events;
1287 /*
1288 * Get allocated in this thread, enqueued to a global queue, dequeued and
1289 * freed in the manage apps thread.
1290 */
1291 struct ust_command *ust_cmd = NULL;
1292
1293 DBG("[thread] Manage application registration started");
1294
1295 ret = lttcomm_listen_unix_sock(apps_sock);
1296 if (ret < 0) {
1297 goto error;
1298 }
1299
1300 /*
1301 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1302 * more will be added to this poll set.
1303 */
1304 ret = create_thread_poll_set(&events, 2);
1305 if (ret < 0) {
1306 goto error;
1307 }
1308
1309 /* Add the application registration socket */
1310 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1311 if (ret < 0) {
1312 goto error;
1313 }
1314
1315 /* Notify all applications to register */
1316 ret = notify_ust_apps(1);
1317 if (ret < 0) {
1318 ERR("Failed to notify applications or create the wait shared memory.\n"
1319 "Execution continues but there might be problem for already\n"
1320 "running applications that wishes to register.");
1321 }
1322
1323 while (1) {
1324 DBG("Accepting application registration");
1325
1326 nb_fd = LTTNG_POLL_GETNB(&events);
1327
1328 /* Inifinite blocking call, waiting for transmission */
1329 ret = lttng_poll_wait(&events, -1);
1330 if (ret < 0) {
1331 goto error;
1332 }
1333
1334 for (i = 0; i < nb_fd; i++) {
1335 /* Fetch once the poll data */
1336 revents = LTTNG_POLL_GETEV(&events, i);
1337 pollfd = LTTNG_POLL_GETFD(&events, i);
1338
1339 /* Thread quit pipe has been closed. Killing thread. */
1340 ret = check_thread_quit_pipe(pollfd, revents);
1341 if (ret) {
1342 goto error;
1343 }
1344
1345 /* Event on the registration socket */
1346 if (pollfd == apps_sock) {
1347 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1348 ERR("Register apps socket poll error");
1349 goto error;
1350 } else if (revents & LPOLLIN) {
1351 sock = lttcomm_accept_unix_sock(apps_sock);
1352 if (sock < 0) {
1353 goto error;
1354 }
1355
1356 /* Create UST registration command for enqueuing */
1357 ust_cmd = zmalloc(sizeof(struct ust_command));
1358 if (ust_cmd == NULL) {
1359 perror("ust command zmalloc");
1360 goto error;
1361 }
1362
1363 /*
1364 * Using message-based transmissions to ensure we don't
1365 * have to deal with partially received messages.
1366 */
1367 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1368 sizeof(struct ust_register_msg));
1369 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1370 if (ret < 0) {
1371 perror("lttcomm_recv_unix_sock register apps");
1372 } else {
1373 ERR("Wrong size received on apps register");
1374 }
1375 free(ust_cmd);
1376 close(sock);
1377 continue;
1378 }
1379
1380 ust_cmd->sock = sock;
1381
1382 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1383 " gid:%d sock:%d name:%s (version %d.%d)",
1384 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1385 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1386 ust_cmd->sock, ust_cmd->reg_msg.name,
1387 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1388
1389 /*
1390 * Lock free enqueue the registration request. The red pill
1391 * has been taken! This apps will be part of the *system*.
1392 */
1393 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1394
1395 /*
1396 * Wake the registration queue futex. Implicit memory
1397 * barrier with the exchange in cds_wfq_enqueue.
1398 */
1399 futex_nto1_wake(&ust_cmd_queue.futex);
1400 }
1401 }
1402 }
1403 }
1404
1405 error:
1406 DBG("UST Registration thread dying");
1407
1408 /* Notify that the registration thread is gone */
1409 notify_ust_apps(0);
1410
1411 close(apps_sock);
1412 close(sock);
1413 unlink(apps_unix_sock_path);
1414
1415 lttng_poll_clean(&events);
1416
1417 return NULL;
1418 }
1419
1420 /*
1421 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1422 * exec or it will fails.
1423 */
1424 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1425 {
1426 int ret;
1427 struct timespec timeout;
1428
1429 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1430 timeout.tv_nsec = 0;
1431
1432 /* Setup semaphore */
1433 ret = sem_init(&consumer_data->sem, 0, 0);
1434 if (ret < 0) {
1435 PERROR("sem_init consumer semaphore");
1436 goto error;
1437 }
1438
1439 ret = pthread_create(&consumer_data->thread, NULL,
1440 thread_manage_consumer, consumer_data);
1441 if (ret != 0) {
1442 PERROR("pthread_create consumer");
1443 ret = -1;
1444 goto error;
1445 }
1446
1447 /* Get time for sem_timedwait absolute timeout */
1448 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1449 if (ret < 0) {
1450 PERROR("clock_gettime spawn consumer");
1451 /* Infinite wait for the kconsumerd thread to be ready */
1452 ret = sem_wait(&consumer_data->sem);
1453 } else {
1454 /* Normal timeout if the gettime was successful */
1455 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1456 ret = sem_timedwait(&consumer_data->sem, &timeout);
1457 }
1458
1459 if (ret < 0) {
1460 if (errno == ETIMEDOUT) {
1461 /*
1462 * Call has timed out so we kill the kconsumerd_thread and return
1463 * an error.
1464 */
1465 ERR("The consumer thread was never ready. Killing it");
1466 ret = pthread_cancel(consumer_data->thread);
1467 if (ret < 0) {
1468 PERROR("pthread_cancel consumer thread");
1469 }
1470 } else {
1471 PERROR("semaphore wait failed consumer thread");
1472 }
1473 goto error;
1474 }
1475
1476 pthread_mutex_lock(&consumer_data->pid_mutex);
1477 if (consumer_data->pid == 0) {
1478 ERR("Kconsumerd did not start");
1479 pthread_mutex_unlock(&consumer_data->pid_mutex);
1480 goto error;
1481 }
1482 pthread_mutex_unlock(&consumer_data->pid_mutex);
1483
1484 return 0;
1485
1486 error:
1487 return ret;
1488 }
1489
1490 /*
1491 * Join consumer thread
1492 */
1493 static int join_consumer_thread(struct consumer_data *consumer_data)
1494 {
1495 void *status;
1496 int ret;
1497
1498 if (consumer_data->pid != 0) {
1499 ret = kill(consumer_data->pid, SIGTERM);
1500 if (ret) {
1501 ERR("Error killing consumer daemon");
1502 return ret;
1503 }
1504 return pthread_join(consumer_data->thread, &status);
1505 } else {
1506 return 0;
1507 }
1508 }
1509
1510 /*
1511 * Fork and exec a consumer daemon (consumerd).
1512 *
1513 * Return pid if successful else -1.
1514 */
1515 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1516 {
1517 int ret;
1518 pid_t pid;
1519 const char *consumer_to_use;
1520 const char *verbosity;
1521 struct stat st;
1522
1523 DBG("Spawning consumerd");
1524
1525 pid = fork();
1526 if (pid == 0) {
1527 /*
1528 * Exec consumerd.
1529 */
1530 if (opt_verbose > 1 || opt_verbose_consumer) {
1531 verbosity = "--verbose";
1532 } else {
1533 verbosity = "--quiet";
1534 }
1535 switch (consumer_data->type) {
1536 case LTTNG_CONSUMER_KERNEL:
1537 /*
1538 * Find out which consumerd to execute. We will
1539 * first try the 64-bit path, then the
1540 * sessiond's installation directory, and
1541 * fallback on the 32-bit one,
1542 */
1543 if (stat(consumerd64_bin, &st) == 0) {
1544 consumer_to_use = consumerd64_bin;
1545 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1546 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1547 } else if (stat(consumerd32_bin, &st) == 0) {
1548 consumer_to_use = consumerd32_bin;
1549 } else {
1550 break;
1551 }
1552 DBG("Using kernel consumer at: %s", consumer_to_use);
1553 execl(consumer_to_use,
1554 "lttng-consumerd", verbosity, "-k",
1555 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1556 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1557 NULL);
1558 break;
1559 case LTTNG_CONSUMER64_UST:
1560 {
1561 char *tmpnew = NULL;
1562
1563 if (consumerd64_libdir[0] != '\0') {
1564 char *tmp;
1565 size_t tmplen;
1566
1567 tmp = getenv("LD_LIBRARY_PATH");
1568 if (!tmp) {
1569 tmp = "";
1570 }
1571 tmplen = strlen("LD_LIBRARY_PATH=")
1572 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1573 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1574 if (!tmpnew) {
1575 ret = -ENOMEM;
1576 goto error;
1577 }
1578 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1579 strcat(tmpnew, consumerd64_libdir);
1580 if (tmp[0] != '\0') {
1581 strcat(tmpnew, ":");
1582 strcat(tmpnew, tmp);
1583 }
1584 ret = putenv(tmpnew);
1585 if (ret) {
1586 ret = -errno;
1587 goto error;
1588 }
1589 }
1590 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1591 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1592 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1593 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1594 NULL);
1595 if (consumerd64_libdir[0] != '\0') {
1596 free(tmpnew);
1597 }
1598 if (ret) {
1599 goto error;
1600 }
1601 break;
1602 }
1603 case LTTNG_CONSUMER32_UST:
1604 {
1605 char *tmpnew = NULL;
1606
1607 if (consumerd32_libdir[0] != '\0') {
1608 char *tmp;
1609 size_t tmplen;
1610
1611 tmp = getenv("LD_LIBRARY_PATH");
1612 if (!tmp) {
1613 tmp = "";
1614 }
1615 tmplen = strlen("LD_LIBRARY_PATH=")
1616 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1617 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1618 if (!tmpnew) {
1619 ret = -ENOMEM;
1620 goto error;
1621 }
1622 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1623 strcat(tmpnew, consumerd32_libdir);
1624 if (tmp[0] != '\0') {
1625 strcat(tmpnew, ":");
1626 strcat(tmpnew, tmp);
1627 }
1628 ret = putenv(tmpnew);
1629 if (ret) {
1630 ret = -errno;
1631 goto error;
1632 }
1633 }
1634 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1635 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1636 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1637 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1638 NULL);
1639 if (consumerd32_libdir[0] != '\0') {
1640 free(tmpnew);
1641 }
1642 if (ret) {
1643 goto error;
1644 }
1645 break;
1646 }
1647 default:
1648 perror("unknown consumer type");
1649 exit(EXIT_FAILURE);
1650 }
1651 if (errno != 0) {
1652 perror("kernel start consumer exec");
1653 }
1654 exit(EXIT_FAILURE);
1655 } else if (pid > 0) {
1656 ret = pid;
1657 } else {
1658 perror("start consumer fork");
1659 ret = -errno;
1660 }
1661 error:
1662 return ret;
1663 }
1664
1665 /*
1666 * Spawn the consumerd daemon and session daemon thread.
1667 */
1668 static int start_consumerd(struct consumer_data *consumer_data)
1669 {
1670 int ret;
1671
1672 pthread_mutex_lock(&consumer_data->pid_mutex);
1673 if (consumer_data->pid != 0) {
1674 pthread_mutex_unlock(&consumer_data->pid_mutex);
1675 goto end;
1676 }
1677
1678 ret = spawn_consumerd(consumer_data);
1679 if (ret < 0) {
1680 ERR("Spawning consumerd failed");
1681 pthread_mutex_unlock(&consumer_data->pid_mutex);
1682 goto error;
1683 }
1684
1685 /* Setting up the consumer_data pid */
1686 consumer_data->pid = ret;
1687 DBG2("Consumer pid %d", consumer_data->pid);
1688 pthread_mutex_unlock(&consumer_data->pid_mutex);
1689
1690 DBG2("Spawning consumer control thread");
1691 ret = spawn_consumer_thread(consumer_data);
1692 if (ret < 0) {
1693 ERR("Fatal error spawning consumer control thread");
1694 goto error;
1695 }
1696
1697 end:
1698 return 0;
1699
1700 error:
1701 return ret;
1702 }
1703
1704 /*
1705 * modprobe_kernel_modules
1706 */
1707 static int modprobe_kernel_modules(void)
1708 {
1709 int ret = 0, i;
1710 char modprobe[256];
1711
1712 for (i = 0; i < ARRAY_SIZE(kernel_modules_list); i++) {
1713 ret = snprintf(modprobe, sizeof(modprobe),
1714 "/sbin/modprobe %s%s",
1715 kernel_modules_list[i].required ? "" : "-q ",
1716 kernel_modules_list[i].name);
1717 if (ret < 0) {
1718 perror("snprintf modprobe");
1719 goto error;
1720 }
1721 modprobe[sizeof(modprobe) - 1] = '\0';
1722 ret = system(modprobe);
1723 if (ret == -1) {
1724 ERR("Unable to launch modprobe for module %s",
1725 kernel_modules_list[i].name);
1726 } else if (kernel_modules_list[i].required
1727 && WEXITSTATUS(ret) != 0) {
1728 ERR("Unable to load module %s",
1729 kernel_modules_list[i].name);
1730 } else {
1731 DBG("Modprobe successfully %s",
1732 kernel_modules_list[i].name);
1733 }
1734 }
1735
1736 error:
1737 return ret;
1738 }
1739
1740 /*
1741 * mount_debugfs
1742 */
1743 static int mount_debugfs(char *path)
1744 {
1745 int ret;
1746 char *type = "debugfs";
1747
1748 ret = mkdir_recursive_run_as(path, S_IRWXU | S_IRWXG, geteuid(), getegid());
1749 if (ret < 0) {
1750 PERROR("Cannot create debugfs path");
1751 goto error;
1752 }
1753
1754 ret = mount(type, path, type, 0, NULL);
1755 if (ret < 0) {
1756 PERROR("Cannot mount debugfs");
1757 goto error;
1758 }
1759
1760 DBG("Mounted debugfs successfully at %s", path);
1761
1762 error:
1763 return ret;
1764 }
1765
1766 /*
1767 * Setup necessary data for kernel tracer action.
1768 */
1769 static void init_kernel_tracer(void)
1770 {
1771 int ret;
1772 char *proc_mounts = "/proc/mounts";
1773 char line[256];
1774 char *debugfs_path = NULL, *lttng_path = NULL;
1775 FILE *fp;
1776
1777 /* Detect debugfs */
1778 fp = fopen(proc_mounts, "r");
1779 if (fp == NULL) {
1780 ERR("Unable to probe %s", proc_mounts);
1781 goto error;
1782 }
1783
1784 while (fgets(line, sizeof(line), fp) != NULL) {
1785 if (strstr(line, "debugfs") != NULL) {
1786 /* Remove first string */
1787 strtok(line, " ");
1788 /* Dup string here so we can reuse line later on */
1789 debugfs_path = strdup(strtok(NULL, " "));
1790 DBG("Got debugfs path : %s", debugfs_path);
1791 break;
1792 }
1793 }
1794
1795 fclose(fp);
1796
1797 /* Mount debugfs if needded */
1798 if (debugfs_path == NULL) {
1799 ret = asprintf(&debugfs_path, "/mnt/debugfs");
1800 if (ret < 0) {
1801 perror("asprintf debugfs path");
1802 goto error;
1803 }
1804 ret = mount_debugfs(debugfs_path);
1805 if (ret < 0) {
1806 perror("Cannot mount debugfs");
1807 goto error;
1808 }
1809 }
1810
1811 /* Modprobe lttng kernel modules */
1812 ret = modprobe_kernel_modules();
1813 if (ret < 0) {
1814 goto error;
1815 }
1816
1817 /* Setup lttng kernel path */
1818 ret = asprintf(&lttng_path, "%s/lttng", debugfs_path);
1819 if (ret < 0) {
1820 perror("asprintf lttng path");
1821 goto error;
1822 }
1823
1824 /* Open debugfs lttng */
1825 kernel_tracer_fd = open(lttng_path, O_RDWR);
1826 if (kernel_tracer_fd < 0) {
1827 DBG("Failed to open %s", lttng_path);
1828 goto error;
1829 }
1830
1831 free(lttng_path);
1832 free(debugfs_path);
1833 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1834 return;
1835
1836 error:
1837 if (lttng_path) {
1838 free(lttng_path);
1839 }
1840 if (debugfs_path) {
1841 free(debugfs_path);
1842 }
1843 WARN("No kernel tracer available");
1844 kernel_tracer_fd = 0;
1845 return;
1846 }
1847
1848 /*
1849 * Init tracing by creating trace directory and sending fds kernel consumer.
1850 */
1851 static int init_kernel_tracing(struct ltt_kernel_session *session)
1852 {
1853 int ret = 0;
1854
1855 if (session->consumer_fds_sent == 0) {
1856 /*
1857 * Assign default kernel consumer socket if no consumer assigned to the
1858 * kernel session. At this point, it's NOT suppose to be 0 but this is
1859 * an extra security check.
1860 */
1861 if (session->consumer_fd == 0) {
1862 session->consumer_fd = kconsumer_data.cmd_sock;
1863 }
1864
1865 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1866 if (ret < 0) {
1867 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1868 goto error;
1869 }
1870
1871 session->consumer_fds_sent = 1;
1872 }
1873
1874 error:
1875 return ret;
1876 }
1877
1878 /*
1879 * Create an UST session and add it to the session ust list.
1880 */
1881 static int create_ust_session(struct ltt_session *session,
1882 struct lttng_domain *domain)
1883 {
1884 struct ltt_ust_session *lus = NULL;
1885 int ret;
1886
1887 switch (domain->type) {
1888 case LTTNG_DOMAIN_UST:
1889 break;
1890 default:
1891 ret = LTTCOMM_UNKNOWN_DOMAIN;
1892 goto error;
1893 }
1894
1895 DBG("Creating UST session");
1896
1897 lus = trace_ust_create_session(session->path, session->id, domain);
1898 if (lus == NULL) {
1899 ret = LTTCOMM_UST_SESS_FAIL;
1900 goto error;
1901 }
1902
1903 ret = mkdir_recursive_run_as(lus->pathname, S_IRWXU | S_IRWXG,
1904 session->uid, session->gid);
1905 if (ret < 0) {
1906 if (ret != -EEXIST) {
1907 ERR("Trace directory creation error");
1908 ret = LTTCOMM_UST_SESS_FAIL;
1909 goto error;
1910 }
1911 }
1912
1913 /* The domain type dictate different actions on session creation */
1914 switch (domain->type) {
1915 case LTTNG_DOMAIN_UST:
1916 /* No ustctl for the global UST domain */
1917 break;
1918 default:
1919 ERR("Unknown UST domain on create session %d", domain->type);
1920 goto error;
1921 }
1922 lus->uid = session->uid;
1923 lus->gid = session->gid;
1924 session->ust_session = lus;
1925
1926 return LTTCOMM_OK;
1927
1928 error:
1929 free(lus);
1930 return ret;
1931 }
1932
1933 /*
1934 * Create a kernel tracer session then create the default channel.
1935 */
1936 static int create_kernel_session(struct ltt_session *session)
1937 {
1938 int ret;
1939
1940 DBG("Creating kernel session");
1941
1942 ret = kernel_create_session(session, kernel_tracer_fd);
1943 if (ret < 0) {
1944 ret = LTTCOMM_KERN_SESS_FAIL;
1945 goto error;
1946 }
1947
1948 /* Set kernel consumer socket fd */
1949 if (kconsumer_data.cmd_sock) {
1950 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1951 }
1952
1953 ret = mkdir_recursive_run_as(session->kernel_session->trace_path,
1954 S_IRWXU | S_IRWXG, session->uid, session->gid);
1955 if (ret < 0) {
1956 if (ret != -EEXIST) {
1957 ERR("Trace directory creation error");
1958 goto error;
1959 }
1960 }
1961 session->kernel_session->uid = session->uid;
1962 session->kernel_session->gid = session->gid;
1963
1964 error:
1965 return ret;
1966 }
1967
1968 /*
1969 * Check if the UID or GID match the session. Root user has access to
1970 * all sessions.
1971 */
1972 static int session_access_ok(struct ltt_session *session,
1973 uid_t uid, gid_t gid)
1974 {
1975 if (uid != session->uid && gid != session->gid
1976 && uid != 0) {
1977 return 0;
1978 } else {
1979 return 1;
1980 }
1981 }
1982
1983 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
1984 {
1985 unsigned int i = 0;
1986 struct ltt_session *session;
1987
1988 DBG("Counting number of available session for UID %d GID %d",
1989 uid, gid);
1990 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
1991 /*
1992 * Only list the sessions the user can control.
1993 */
1994 if (!session_access_ok(session, uid, gid)) {
1995 continue;
1996 }
1997 i++;
1998 }
1999 return i;
2000 }
2001
2002 /*
2003 * Using the session list, filled a lttng_session array to send back to the
2004 * client for session listing.
2005 *
2006 * The session list lock MUST be acquired before calling this function. Use
2007 * session_lock_list() and session_unlock_list().
2008 */
2009 static void list_lttng_sessions(struct lttng_session *sessions,
2010 uid_t uid, gid_t gid)
2011 {
2012 unsigned int i = 0;
2013 struct ltt_session *session;
2014
2015 DBG("Getting all available session for UID %d GID %d",
2016 uid, gid);
2017 /*
2018 * Iterate over session list and append data after the control struct in
2019 * the buffer.
2020 */
2021 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2022 /*
2023 * Only list the sessions the user can control.
2024 */
2025 if (!session_access_ok(session, uid, gid)) {
2026 continue;
2027 }
2028 strncpy(sessions[i].path, session->path, PATH_MAX);
2029 sessions[i].path[PATH_MAX - 1] = '\0';
2030 strncpy(sessions[i].name, session->name, NAME_MAX);
2031 sessions[i].name[NAME_MAX - 1] = '\0';
2032 sessions[i].enabled = session->enabled;
2033 i++;
2034 }
2035 }
2036
2037 /*
2038 * Fill lttng_channel array of all channels.
2039 */
2040 static void list_lttng_channels(int domain, struct ltt_session *session,
2041 struct lttng_channel *channels)
2042 {
2043 int i = 0;
2044 struct ltt_kernel_channel *kchan;
2045
2046 DBG("Listing channels for session %s", session->name);
2047
2048 switch (domain) {
2049 case LTTNG_DOMAIN_KERNEL:
2050 /* Kernel channels */
2051 if (session->kernel_session != NULL) {
2052 cds_list_for_each_entry(kchan,
2053 &session->kernel_session->channel_list.head, list) {
2054 /* Copy lttng_channel struct to array */
2055 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2056 channels[i].enabled = kchan->enabled;
2057 i++;
2058 }
2059 }
2060 break;
2061 case LTTNG_DOMAIN_UST:
2062 {
2063 struct lttng_ht_iter iter;
2064 struct ltt_ust_channel *uchan;
2065
2066 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
2067 &iter.iter, uchan, node.node) {
2068 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2069 channels[i].attr.overwrite = uchan->attr.overwrite;
2070 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2071 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2072 channels[i].attr.switch_timer_interval =
2073 uchan->attr.switch_timer_interval;
2074 channels[i].attr.read_timer_interval =
2075 uchan->attr.read_timer_interval;
2076 channels[i].enabled = uchan->enabled;
2077 switch (uchan->attr.output) {
2078 case LTTNG_UST_MMAP:
2079 default:
2080 channels[i].attr.output = LTTNG_EVENT_MMAP;
2081 break;
2082 }
2083 i++;
2084 }
2085 break;
2086 }
2087 default:
2088 break;
2089 }
2090 }
2091
2092 /*
2093 * Create a list of ust global domain events.
2094 */
2095 static int list_lttng_ust_global_events(char *channel_name,
2096 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2097 {
2098 int i = 0, ret = 0;
2099 unsigned int nb_event = 0;
2100 struct lttng_ht_iter iter;
2101 struct lttng_ht_node_str *node;
2102 struct ltt_ust_channel *uchan;
2103 struct ltt_ust_event *uevent;
2104 struct lttng_event *tmp;
2105
2106 DBG("Listing UST global events for channel %s", channel_name);
2107
2108 rcu_read_lock();
2109
2110 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2111 node = lttng_ht_iter_get_node_str(&iter);
2112 if (node == NULL) {
2113 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2114 goto error;
2115 }
2116
2117 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2118
2119 nb_event += lttng_ht_get_count(uchan->events);
2120
2121 if (nb_event == 0) {
2122 ret = nb_event;
2123 goto error;
2124 }
2125
2126 DBG3("Listing UST global %d events", nb_event);
2127
2128 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2129 if (tmp == NULL) {
2130 ret = -LTTCOMM_FATAL;
2131 goto error;
2132 }
2133
2134 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2135 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2136 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2137 tmp[i].enabled = uevent->enabled;
2138 switch (uevent->attr.instrumentation) {
2139 case LTTNG_UST_TRACEPOINT:
2140 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2141 break;
2142 case LTTNG_UST_PROBE:
2143 tmp[i].type = LTTNG_EVENT_PROBE;
2144 break;
2145 case LTTNG_UST_FUNCTION:
2146 tmp[i].type = LTTNG_EVENT_FUNCTION;
2147 break;
2148 case LTTNG_UST_TRACEPOINT_LOGLEVEL:
2149 tmp[i].type = LTTNG_EVENT_TRACEPOINT_LOGLEVEL;
2150 break;
2151 }
2152 i++;
2153 }
2154
2155 ret = nb_event;
2156 *events = tmp;
2157
2158 error:
2159 rcu_read_unlock();
2160 return ret;
2161 }
2162
2163 /*
2164 * Fill lttng_event array of all kernel events in the channel.
2165 */
2166 static int list_lttng_kernel_events(char *channel_name,
2167 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2168 {
2169 int i = 0, ret;
2170 unsigned int nb_event;
2171 struct ltt_kernel_event *event;
2172 struct ltt_kernel_channel *kchan;
2173
2174 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2175 if (kchan == NULL) {
2176 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2177 goto error;
2178 }
2179
2180 nb_event = kchan->event_count;
2181
2182 DBG("Listing events for channel %s", kchan->channel->name);
2183
2184 if (nb_event == 0) {
2185 ret = nb_event;
2186 goto error;
2187 }
2188
2189 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2190 if (*events == NULL) {
2191 ret = LTTCOMM_FATAL;
2192 goto error;
2193 }
2194
2195 /* Kernel channels */
2196 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2197 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2198 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2199 (*events)[i].enabled = event->enabled;
2200 switch (event->event->instrumentation) {
2201 case LTTNG_KERNEL_TRACEPOINT:
2202 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2203 break;
2204 case LTTNG_KERNEL_KPROBE:
2205 case LTTNG_KERNEL_KRETPROBE:
2206 (*events)[i].type = LTTNG_EVENT_PROBE;
2207 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2208 sizeof(struct lttng_kernel_kprobe));
2209 break;
2210 case LTTNG_KERNEL_FUNCTION:
2211 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2212 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2213 sizeof(struct lttng_kernel_function));
2214 break;
2215 case LTTNG_KERNEL_NOOP:
2216 (*events)[i].type = LTTNG_EVENT_NOOP;
2217 break;
2218 case LTTNG_KERNEL_SYSCALL:
2219 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2220 break;
2221 case LTTNG_KERNEL_ALL:
2222 assert(0);
2223 break;
2224 }
2225 i++;
2226 }
2227
2228 return nb_event;
2229
2230 error:
2231 return ret;
2232 }
2233
2234 /*
2235 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2236 */
2237 static int cmd_disable_channel(struct ltt_session *session,
2238 int domain, char *channel_name)
2239 {
2240 int ret;
2241 struct ltt_ust_session *usess;
2242
2243 usess = session->ust_session;
2244
2245 switch (domain) {
2246 case LTTNG_DOMAIN_KERNEL:
2247 {
2248 ret = channel_kernel_disable(session->kernel_session,
2249 channel_name);
2250 if (ret != LTTCOMM_OK) {
2251 goto error;
2252 }
2253
2254 kernel_wait_quiescent(kernel_tracer_fd);
2255 break;
2256 }
2257 case LTTNG_DOMAIN_UST:
2258 {
2259 struct ltt_ust_channel *uchan;
2260 struct lttng_ht *chan_ht;
2261
2262 chan_ht = usess->domain_global.channels;
2263
2264 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2265 if (uchan == NULL) {
2266 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2267 goto error;
2268 }
2269
2270 ret = channel_ust_disable(usess, domain, uchan);
2271 if (ret != LTTCOMM_OK) {
2272 goto error;
2273 }
2274 break;
2275 }
2276 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2277 case LTTNG_DOMAIN_UST_EXEC_NAME:
2278 case LTTNG_DOMAIN_UST_PID:
2279 ret = LTTCOMM_NOT_IMPLEMENTED;
2280 goto error;
2281 default:
2282 ret = LTTCOMM_UNKNOWN_DOMAIN;
2283 goto error;
2284 }
2285
2286 ret = LTTCOMM_OK;
2287
2288 error:
2289 return ret;
2290 }
2291
2292 /*
2293 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2294 */
2295 static int cmd_enable_channel(struct ltt_session *session,
2296 int domain, struct lttng_channel *attr)
2297 {
2298 int ret;
2299 struct ltt_ust_session *usess = session->ust_session;
2300 struct lttng_ht *chan_ht;
2301
2302 DBG("Enabling channel %s for session %s", attr->name, session->name);
2303
2304 switch (domain) {
2305 case LTTNG_DOMAIN_KERNEL:
2306 {
2307 struct ltt_kernel_channel *kchan;
2308
2309 kchan = trace_kernel_get_channel_by_name(attr->name,
2310 session->kernel_session);
2311 if (kchan == NULL) {
2312 ret = channel_kernel_create(session->kernel_session,
2313 attr, kernel_poll_pipe[1]);
2314 } else {
2315 ret = channel_kernel_enable(session->kernel_session, kchan);
2316 }
2317
2318 if (ret != LTTCOMM_OK) {
2319 goto error;
2320 }
2321
2322 kernel_wait_quiescent(kernel_tracer_fd);
2323 break;
2324 }
2325 case LTTNG_DOMAIN_UST:
2326 {
2327 struct ltt_ust_channel *uchan;
2328
2329 chan_ht = usess->domain_global.channels;
2330
2331 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2332 if (uchan == NULL) {
2333 ret = channel_ust_create(usess, domain, attr);
2334 } else {
2335 ret = channel_ust_enable(usess, domain, uchan);
2336 }
2337 break;
2338 }
2339 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2340 case LTTNG_DOMAIN_UST_EXEC_NAME:
2341 case LTTNG_DOMAIN_UST_PID:
2342 ret = LTTCOMM_NOT_IMPLEMENTED;
2343 goto error;
2344 default:
2345 ret = LTTCOMM_UNKNOWN_DOMAIN;
2346 goto error;
2347 }
2348
2349 error:
2350 return ret;
2351 }
2352
2353 /*
2354 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2355 */
2356 static int cmd_disable_event(struct ltt_session *session, int domain,
2357 char *channel_name, char *event_name)
2358 {
2359 int ret;
2360
2361 switch (domain) {
2362 case LTTNG_DOMAIN_KERNEL:
2363 {
2364 struct ltt_kernel_channel *kchan;
2365 struct ltt_kernel_session *ksess;
2366
2367 ksess = session->kernel_session;
2368
2369 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2370 if (kchan == NULL) {
2371 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2372 goto error;
2373 }
2374
2375 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2376 if (ret != LTTCOMM_OK) {
2377 goto error;
2378 }
2379
2380 kernel_wait_quiescent(kernel_tracer_fd);
2381 break;
2382 }
2383 case LTTNG_DOMAIN_UST:
2384 {
2385 struct ltt_ust_channel *uchan;
2386 struct ltt_ust_session *usess;
2387
2388 usess = session->ust_session;
2389
2390 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2391 channel_name);
2392 if (uchan == NULL) {
2393 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2394 goto error;
2395 }
2396
2397 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2398 if (ret != LTTCOMM_OK) {
2399 goto error;
2400 }
2401
2402 DBG3("Disable UST event %s in channel %s completed", event_name,
2403 channel_name);
2404 break;
2405 }
2406 case LTTNG_DOMAIN_UST_EXEC_NAME:
2407 case LTTNG_DOMAIN_UST_PID:
2408 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2409 default:
2410 ret = LTTCOMM_NOT_IMPLEMENTED;
2411 goto error;
2412 }
2413
2414 ret = LTTCOMM_OK;
2415
2416 error:
2417 return ret;
2418 }
2419
2420 /*
2421 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2422 */
2423 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2424 char *channel_name)
2425 {
2426 int ret;
2427
2428 switch (domain) {
2429 case LTTNG_DOMAIN_KERNEL:
2430 {
2431 struct ltt_kernel_session *ksess;
2432 struct ltt_kernel_channel *kchan;
2433
2434 ksess = session->kernel_session;
2435
2436 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2437 if (kchan == NULL) {
2438 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2439 goto error;
2440 }
2441
2442 ret = event_kernel_disable_all(ksess, kchan);
2443 if (ret != LTTCOMM_OK) {
2444 goto error;
2445 }
2446
2447 kernel_wait_quiescent(kernel_tracer_fd);
2448 break;
2449 }
2450 case LTTNG_DOMAIN_UST:
2451 {
2452 struct ltt_ust_session *usess;
2453 struct ltt_ust_channel *uchan;
2454
2455 usess = session->ust_session;
2456
2457 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2458 channel_name);
2459 if (uchan == NULL) {
2460 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2461 goto error;
2462 }
2463
2464 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2465 if (ret != 0) {
2466 goto error;
2467 }
2468
2469 DBG3("Disable all UST events in channel %s completed", channel_name);
2470
2471 break;
2472 }
2473 case LTTNG_DOMAIN_UST_EXEC_NAME:
2474 case LTTNG_DOMAIN_UST_PID:
2475 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2476 default:
2477 ret = LTTCOMM_NOT_IMPLEMENTED;
2478 goto error;
2479 }
2480
2481 ret = LTTCOMM_OK;
2482
2483 error:
2484 return ret;
2485 }
2486
2487 /*
2488 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2489 */
2490 static int cmd_add_context(struct ltt_session *session, int domain,
2491 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2492 {
2493 int ret;
2494
2495 switch (domain) {
2496 case LTTNG_DOMAIN_KERNEL:
2497 /* Add kernel context to kernel tracer */
2498 ret = context_kernel_add(session->kernel_session, ctx,
2499 event_name, channel_name);
2500 if (ret != LTTCOMM_OK) {
2501 goto error;
2502 }
2503 break;
2504 case LTTNG_DOMAIN_UST:
2505 {
2506 struct ltt_ust_session *usess = session->ust_session;
2507
2508 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2509 if (ret != LTTCOMM_OK) {
2510 goto error;
2511 }
2512 break;
2513 }
2514 case LTTNG_DOMAIN_UST_EXEC_NAME:
2515 case LTTNG_DOMAIN_UST_PID:
2516 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2517 default:
2518 ret = LTTCOMM_NOT_IMPLEMENTED;
2519 goto error;
2520 }
2521
2522 ret = LTTCOMM_OK;
2523
2524 error:
2525 return ret;
2526 }
2527
2528 /*
2529 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2530 *
2531 * TODO: currently, both events and loglevels are kept within the same
2532 * namespace for UST global registry/app registery, so if an event
2533 * happen to have the same name as the loglevel (very unlikely though),
2534 * and an attempt is made to enable/disable both in the same session,
2535 * the first to be created will be the only one allowed to exist.
2536 */
2537 static int cmd_enable_event(struct ltt_session *session, int domain,
2538 char *channel_name, struct lttng_event *event)
2539 {
2540 int ret;
2541 struct lttng_channel *attr;
2542 struct ltt_ust_session *usess = session->ust_session;
2543
2544 switch (domain) {
2545 case LTTNG_DOMAIN_KERNEL:
2546 {
2547 struct ltt_kernel_channel *kchan;
2548
2549 kchan = trace_kernel_get_channel_by_name(channel_name,
2550 session->kernel_session);
2551 if (kchan == NULL) {
2552 attr = channel_new_default_attr(domain);
2553 if (attr == NULL) {
2554 ret = LTTCOMM_FATAL;
2555 goto error;
2556 }
2557 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2558
2559 /* This call will notify the kernel thread */
2560 ret = channel_kernel_create(session->kernel_session,
2561 attr, kernel_poll_pipe[1]);
2562 if (ret != LTTCOMM_OK) {
2563 free(attr);
2564 goto error;
2565 }
2566 free(attr);
2567 }
2568
2569 /* Get the newly created kernel channel pointer */
2570 kchan = trace_kernel_get_channel_by_name(channel_name,
2571 session->kernel_session);
2572 if (kchan == NULL) {
2573 /* This sould not happen... */
2574 ret = LTTCOMM_FATAL;
2575 goto error;
2576 }
2577
2578 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2579 event);
2580 if (ret != LTTCOMM_OK) {
2581 goto error;
2582 }
2583
2584 kernel_wait_quiescent(kernel_tracer_fd);
2585 break;
2586 }
2587 case LTTNG_DOMAIN_UST:
2588 {
2589 struct lttng_channel *attr;
2590 struct ltt_ust_channel *uchan;
2591
2592 /* Get channel from global UST domain */
2593 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2594 channel_name);
2595 if (uchan == NULL) {
2596 /* Create default channel */
2597 attr = channel_new_default_attr(domain);
2598 if (attr == NULL) {
2599 ret = LTTCOMM_FATAL;
2600 goto error;
2601 }
2602 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2603 attr->name[NAME_MAX - 1] = '\0';
2604
2605 ret = channel_ust_create(usess, domain, attr);
2606 if (ret != LTTCOMM_OK) {
2607 free(attr);
2608 goto error;
2609 }
2610 free(attr);
2611
2612 /* Get the newly created channel reference back */
2613 uchan = trace_ust_find_channel_by_name(
2614 usess->domain_global.channels, channel_name);
2615 if (uchan == NULL) {
2616 /* Something is really wrong */
2617 ret = LTTCOMM_FATAL;
2618 goto error;
2619 }
2620 }
2621
2622 /* At this point, the session and channel exist on the tracer */
2623 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2624 if (ret != LTTCOMM_OK) {
2625 goto error;
2626 }
2627 break;
2628 }
2629 case LTTNG_DOMAIN_UST_EXEC_NAME:
2630 case LTTNG_DOMAIN_UST_PID:
2631 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2632 default:
2633 ret = LTTCOMM_NOT_IMPLEMENTED;
2634 goto error;
2635 }
2636
2637 ret = LTTCOMM_OK;
2638
2639 error:
2640 return ret;
2641 }
2642
2643 /*
2644 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2645 */
2646 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2647 char *channel_name, int event_type)
2648 {
2649 int ret;
2650 struct ltt_kernel_channel *kchan;
2651
2652 switch (domain) {
2653 case LTTNG_DOMAIN_KERNEL:
2654 kchan = trace_kernel_get_channel_by_name(channel_name,
2655 session->kernel_session);
2656 if (kchan == NULL) {
2657 /* This call will notify the kernel thread */
2658 ret = channel_kernel_create(session->kernel_session, NULL,
2659 kernel_poll_pipe[1]);
2660 if (ret != LTTCOMM_OK) {
2661 goto error;
2662 }
2663
2664 /* Get the newly created kernel channel pointer */
2665 kchan = trace_kernel_get_channel_by_name(channel_name,
2666 session->kernel_session);
2667 if (kchan == NULL) {
2668 /* This sould not happen... */
2669 ret = LTTCOMM_FATAL;
2670 goto error;
2671 }
2672
2673 }
2674
2675 switch (event_type) {
2676 case LTTNG_EVENT_SYSCALL:
2677 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2678 kchan, kernel_tracer_fd);
2679 break;
2680 case LTTNG_EVENT_TRACEPOINT:
2681 /*
2682 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2683 * events already registered to the channel.
2684 */
2685 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2686 kchan, kernel_tracer_fd);
2687 break;
2688 case LTTNG_EVENT_ALL:
2689 /* Enable syscalls and tracepoints */
2690 ret = event_kernel_enable_all(session->kernel_session,
2691 kchan, kernel_tracer_fd);
2692 break;
2693 default:
2694 ret = LTTCOMM_KERN_ENABLE_FAIL;
2695 goto error;
2696 }
2697
2698 /* Manage return value */
2699 if (ret != LTTCOMM_OK) {
2700 goto error;
2701 }
2702
2703 kernel_wait_quiescent(kernel_tracer_fd);
2704 break;
2705 case LTTNG_DOMAIN_UST:
2706 {
2707 struct lttng_channel *attr;
2708 struct ltt_ust_channel *uchan;
2709 struct ltt_ust_session *usess = session->ust_session;
2710
2711 /* Get channel from global UST domain */
2712 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2713 channel_name);
2714 if (uchan == NULL) {
2715 /* Create default channel */
2716 attr = channel_new_default_attr(domain);
2717 if (attr == NULL) {
2718 ret = LTTCOMM_FATAL;
2719 goto error;
2720 }
2721 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2722 attr->name[NAME_MAX - 1] = '\0';
2723
2724 /* Use the internal command enable channel */
2725 ret = channel_ust_create(usess, domain, attr);
2726 if (ret != LTTCOMM_OK) {
2727 free(attr);
2728 goto error;
2729 }
2730 free(attr);
2731
2732 /* Get the newly created channel reference back */
2733 uchan = trace_ust_find_channel_by_name(
2734 usess->domain_global.channels, channel_name);
2735 if (uchan == NULL) {
2736 /* Something is really wrong */
2737 ret = LTTCOMM_FATAL;
2738 goto error;
2739 }
2740 }
2741
2742 /* At this point, the session and channel exist on the tracer */
2743
2744 switch (event_type) {
2745 case LTTNG_EVENT_ALL:
2746 case LTTNG_EVENT_TRACEPOINT:
2747 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2748 if (ret != LTTCOMM_OK) {
2749 goto error;
2750 }
2751 break;
2752 default:
2753 ret = LTTCOMM_UST_ENABLE_FAIL;
2754 goto error;
2755 }
2756
2757 /* Manage return value */
2758 if (ret != LTTCOMM_OK) {
2759 goto error;
2760 }
2761
2762 break;
2763 }
2764 case LTTNG_DOMAIN_UST_EXEC_NAME:
2765 case LTTNG_DOMAIN_UST_PID:
2766 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2767 default:
2768 ret = LTTCOMM_NOT_IMPLEMENTED;
2769 goto error;
2770 }
2771
2772 ret = LTTCOMM_OK;
2773
2774 error:
2775 return ret;
2776 }
2777
2778 /*
2779 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2780 */
2781 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2782 {
2783 int ret;
2784 ssize_t nb_events = 0;
2785
2786 switch (domain) {
2787 case LTTNG_DOMAIN_KERNEL:
2788 nb_events = kernel_list_events(kernel_tracer_fd, events);
2789 if (nb_events < 0) {
2790 ret = LTTCOMM_KERN_LIST_FAIL;
2791 goto error;
2792 }
2793 break;
2794 case LTTNG_DOMAIN_UST:
2795 nb_events = ust_app_list_events(events);
2796 if (nb_events < 0) {
2797 ret = LTTCOMM_UST_LIST_FAIL;
2798 goto error;
2799 }
2800 break;
2801 default:
2802 ret = LTTCOMM_NOT_IMPLEMENTED;
2803 goto error;
2804 }
2805
2806 return nb_events;
2807
2808 error:
2809 /* Return negative value to differentiate return code */
2810 return -ret;
2811 }
2812
2813 /*
2814 * Command LTTNG_START_TRACE processed by the client thread.
2815 */
2816 static int cmd_start_trace(struct ltt_session *session)
2817 {
2818 int ret;
2819 struct ltt_kernel_session *ksession;
2820 struct ltt_ust_session *usess;
2821
2822 /* Short cut */
2823 ksession = session->kernel_session;
2824 usess = session->ust_session;
2825
2826 if (session->enabled) {
2827 ret = LTTCOMM_UST_START_FAIL;
2828 goto error;
2829 }
2830
2831 session->enabled = 1;
2832
2833 /* Kernel tracing */
2834 if (ksession != NULL) {
2835 struct ltt_kernel_channel *kchan;
2836
2837 /* Open kernel metadata */
2838 if (ksession->metadata == NULL) {
2839 ret = kernel_open_metadata(ksession, ksession->trace_path);
2840 if (ret < 0) {
2841 ret = LTTCOMM_KERN_META_FAIL;
2842 goto error;
2843 }
2844 }
2845
2846 /* Open kernel metadata stream */
2847 if (ksession->metadata_stream_fd == 0) {
2848 ret = kernel_open_metadata_stream(ksession);
2849 if (ret < 0) {
2850 ERR("Kernel create metadata stream failed");
2851 ret = LTTCOMM_KERN_STREAM_FAIL;
2852 goto error;
2853 }
2854 }
2855
2856 /* For each channel */
2857 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2858 if (kchan->stream_count == 0) {
2859 ret = kernel_open_channel_stream(kchan);
2860 if (ret < 0) {
2861 ret = LTTCOMM_KERN_STREAM_FAIL;
2862 goto error;
2863 }
2864 /* Update the stream global counter */
2865 ksession->stream_count_global += ret;
2866 }
2867 }
2868
2869 /* Setup kernel consumer socket and send fds to it */
2870 ret = init_kernel_tracing(ksession);
2871 if (ret < 0) {
2872 ret = LTTCOMM_KERN_START_FAIL;
2873 goto error;
2874 }
2875
2876 /* This start the kernel tracing */
2877 ret = kernel_start_session(ksession);
2878 if (ret < 0) {
2879 ret = LTTCOMM_KERN_START_FAIL;
2880 goto error;
2881 }
2882
2883 /* Quiescent wait after starting trace */
2884 kernel_wait_quiescent(kernel_tracer_fd);
2885 }
2886
2887 /* Flag session that trace should start automatically */
2888 if (usess) {
2889 usess->start_trace = 1;
2890
2891 ret = ust_app_start_trace_all(usess);
2892 if (ret < 0) {
2893 ret = LTTCOMM_UST_START_FAIL;
2894 goto error;
2895 }
2896 }
2897
2898 ret = LTTCOMM_OK;
2899
2900 error:
2901 return ret;
2902 }
2903
2904 /*
2905 * Command LTTNG_STOP_TRACE processed by the client thread.
2906 */
2907 static int cmd_stop_trace(struct ltt_session *session)
2908 {
2909 int ret;
2910 struct ltt_kernel_channel *kchan;
2911 struct ltt_kernel_session *ksession;
2912 struct ltt_ust_session *usess;
2913
2914 /* Short cut */
2915 ksession = session->kernel_session;
2916 usess = session->ust_session;
2917
2918 if (!session->enabled) {
2919 ret = LTTCOMM_UST_START_FAIL;
2920 goto error;
2921 }
2922
2923 session->enabled = 0;
2924
2925 /* Kernel tracer */
2926 if (ksession != NULL) {
2927 DBG("Stop kernel tracing");
2928
2929 /* Flush all buffers before stopping */
2930 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2931 if (ret < 0) {
2932 ERR("Kernel metadata flush failed");
2933 }
2934
2935 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2936 ret = kernel_flush_buffer(kchan);
2937 if (ret < 0) {
2938 ERR("Kernel flush buffer error");
2939 }
2940 }
2941
2942 ret = kernel_stop_session(ksession);
2943 if (ret < 0) {
2944 ret = LTTCOMM_KERN_STOP_FAIL;
2945 goto error;
2946 }
2947
2948 kernel_wait_quiescent(kernel_tracer_fd);
2949 }
2950
2951 if (usess) {
2952 usess->start_trace = 0;
2953
2954 ret = ust_app_stop_trace_all(usess);
2955 if (ret < 0) {
2956 ret = LTTCOMM_UST_START_FAIL;
2957 goto error;
2958 }
2959 }
2960
2961 ret = LTTCOMM_OK;
2962
2963 error:
2964 return ret;
2965 }
2966
2967 /*
2968 * Command LTTNG_CREATE_SESSION processed by the client thread.
2969 */
2970 static int cmd_create_session(char *name, char *path, struct ucred *creds)
2971 {
2972 int ret;
2973
2974 ret = session_create(name, path, creds->uid, creds->gid);
2975 if (ret != LTTCOMM_OK) {
2976 goto error;
2977 }
2978
2979 ret = LTTCOMM_OK;
2980
2981 error:
2982 return ret;
2983 }
2984
2985 /*
2986 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2987 */
2988 static int cmd_destroy_session(struct ltt_session *session, char *name)
2989 {
2990 int ret;
2991
2992 /* Clean kernel session teardown */
2993 teardown_kernel_session(session);
2994 /* UST session teardown */
2995 teardown_ust_session(session);
2996
2997 /*
2998 * Must notify the kernel thread here to update it's poll setin order
2999 * to remove the channel(s)' fd just destroyed.
3000 */
3001 ret = notify_thread_pipe(kernel_poll_pipe[1]);
3002 if (ret < 0) {
3003 perror("write kernel poll pipe");
3004 }
3005
3006 ret = session_destroy(session);
3007
3008 return ret;
3009 }
3010
3011 /*
3012 * Command LTTNG_CALIBRATE processed by the client thread.
3013 */
3014 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3015 {
3016 int ret;
3017
3018 switch (domain) {
3019 case LTTNG_DOMAIN_KERNEL:
3020 {
3021 struct lttng_kernel_calibrate kcalibrate;
3022
3023 kcalibrate.type = calibrate->type;
3024 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3025 if (ret < 0) {
3026 ret = LTTCOMM_KERN_ENABLE_FAIL;
3027 goto error;
3028 }
3029 break;
3030 }
3031 default:
3032 /* TODO: Userspace tracing */
3033 ret = LTTCOMM_NOT_IMPLEMENTED;
3034 goto error;
3035 }
3036
3037 ret = LTTCOMM_OK;
3038
3039 error:
3040 return ret;
3041 }
3042
3043 /*
3044 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3045 */
3046 static int cmd_register_consumer(struct ltt_session *session, int domain,
3047 char *sock_path)
3048 {
3049 int ret, sock;
3050
3051 switch (domain) {
3052 case LTTNG_DOMAIN_KERNEL:
3053 /* Can't register a consumer if there is already one */
3054 if (session->kernel_session->consumer_fds_sent != 0) {
3055 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3056 goto error;
3057 }
3058
3059 sock = lttcomm_connect_unix_sock(sock_path);
3060 if (sock < 0) {
3061 ret = LTTCOMM_CONNECT_FAIL;
3062 goto error;
3063 }
3064
3065 session->kernel_session->consumer_fd = sock;
3066 break;
3067 default:
3068 /* TODO: Userspace tracing */
3069 ret = LTTCOMM_NOT_IMPLEMENTED;
3070 goto error;
3071 }
3072
3073 ret = LTTCOMM_OK;
3074
3075 error:
3076 return ret;
3077 }
3078
3079 /*
3080 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3081 */
3082 static ssize_t cmd_list_domains(struct ltt_session *session,
3083 struct lttng_domain **domains)
3084 {
3085 int ret, index = 0;
3086 ssize_t nb_dom = 0;
3087
3088 if (session->kernel_session != NULL) {
3089 DBG3("Listing domains found kernel domain");
3090 nb_dom++;
3091 }
3092
3093 if (session->ust_session != NULL) {
3094 DBG3("Listing domains found UST global domain");
3095 nb_dom++;
3096 }
3097
3098 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3099 if (*domains == NULL) {
3100 ret = -LTTCOMM_FATAL;
3101 goto error;
3102 }
3103
3104 if (session->kernel_session != NULL) {
3105 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3106 index++;
3107 }
3108
3109 if (session->ust_session != NULL) {
3110 (*domains)[index].type = LTTNG_DOMAIN_UST;
3111 index++;
3112 }
3113
3114 return nb_dom;
3115
3116 error:
3117 return ret;
3118 }
3119
3120 /*
3121 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3122 */
3123 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3124 struct lttng_channel **channels)
3125 {
3126 int ret;
3127 ssize_t nb_chan = 0;
3128
3129 switch (domain) {
3130 case LTTNG_DOMAIN_KERNEL:
3131 if (session->kernel_session != NULL) {
3132 nb_chan = session->kernel_session->channel_count;
3133 }
3134 DBG3("Number of kernel channels %zd", nb_chan);
3135 break;
3136 case LTTNG_DOMAIN_UST:
3137 if (session->ust_session != NULL) {
3138 nb_chan = lttng_ht_get_count(
3139 session->ust_session->domain_global.channels);
3140 }
3141 DBG3("Number of UST global channels %zd", nb_chan);
3142 break;
3143 default:
3144 *channels = NULL;
3145 ret = -LTTCOMM_NOT_IMPLEMENTED;
3146 goto error;
3147 }
3148
3149 if (nb_chan > 0) {
3150 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3151 if (*channels == NULL) {
3152 ret = -LTTCOMM_FATAL;
3153 goto error;
3154 }
3155
3156 list_lttng_channels(domain, session, *channels);
3157 } else {
3158 *channels = NULL;
3159 }
3160
3161 return nb_chan;
3162
3163 error:
3164 return ret;
3165 }
3166
3167 /*
3168 * Command LTTNG_LIST_EVENTS processed by the client thread.
3169 */
3170 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3171 char *channel_name, struct lttng_event **events)
3172 {
3173 int ret = 0;
3174 ssize_t nb_event = 0;
3175
3176 switch (domain) {
3177 case LTTNG_DOMAIN_KERNEL:
3178 if (session->kernel_session != NULL) {
3179 nb_event = list_lttng_kernel_events(channel_name,
3180 session->kernel_session, events);
3181 }
3182 break;
3183 case LTTNG_DOMAIN_UST:
3184 {
3185 if (session->ust_session != NULL) {
3186 nb_event = list_lttng_ust_global_events(channel_name,
3187 &session->ust_session->domain_global, events);
3188 }
3189 break;
3190 }
3191 default:
3192 ret = -LTTCOMM_NOT_IMPLEMENTED;
3193 goto error;
3194 }
3195
3196 ret = nb_event;
3197
3198 error:
3199 return ret;
3200 }
3201
3202 /*
3203 * Process the command requested by the lttng client within the command
3204 * context structure. This function make sure that the return structure (llm)
3205 * is set and ready for transmission before returning.
3206 *
3207 * Return any error encountered or 0 for success.
3208 */
3209 static int process_client_msg(struct command_ctx *cmd_ctx)
3210 {
3211 int ret = LTTCOMM_OK;
3212 int need_tracing_session = 1;
3213
3214 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3215
3216 if (opt_no_kernel && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
3217 ret = LTTCOMM_KERN_NA;
3218 goto error;
3219 }
3220
3221 /*
3222 * Check for command that don't needs to allocate a returned payload. We do
3223 * this here so we don't have to make the call for no payload at each
3224 * command.
3225 */
3226 switch(cmd_ctx->lsm->cmd_type) {
3227 case LTTNG_LIST_SESSIONS:
3228 case LTTNG_LIST_TRACEPOINTS:
3229 case LTTNG_LIST_DOMAINS:
3230 case LTTNG_LIST_CHANNELS:
3231 case LTTNG_LIST_EVENTS:
3232 break;
3233 default:
3234 /* Setup lttng message with no payload */
3235 ret = setup_lttng_msg(cmd_ctx, 0);
3236 if (ret < 0) {
3237 /* This label does not try to unlock the session */
3238 goto init_setup_error;
3239 }
3240 }
3241
3242 /* Commands that DO NOT need a session. */
3243 switch (cmd_ctx->lsm->cmd_type) {
3244 case LTTNG_CALIBRATE:
3245 case LTTNG_CREATE_SESSION:
3246 case LTTNG_LIST_SESSIONS:
3247 case LTTNG_LIST_TRACEPOINTS:
3248 need_tracing_session = 0;
3249 break;
3250 default:
3251 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3252 session_lock_list();
3253 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3254 session_unlock_list();
3255 if (cmd_ctx->session == NULL) {
3256 if (cmd_ctx->lsm->session.name != NULL) {
3257 ret = LTTCOMM_SESS_NOT_FOUND;
3258 } else {
3259 /* If no session name specified */
3260 ret = LTTCOMM_SELECT_SESS;
3261 }
3262 goto error;
3263 } else {
3264 /* Acquire lock for the session */
3265 session_lock(cmd_ctx->session);
3266 }
3267 break;
3268 }
3269
3270 /*
3271 * Check domain type for specific "pre-action".
3272 */
3273 switch (cmd_ctx->lsm->domain.type) {
3274 case LTTNG_DOMAIN_KERNEL:
3275 /* Kernel tracer check */
3276 if (kernel_tracer_fd == 0) {
3277 /* Basically, load kernel tracer modules */
3278 init_kernel_tracer();
3279 if (kernel_tracer_fd == 0) {
3280 ret = LTTCOMM_KERN_NA;
3281 goto error;
3282 }
3283 }
3284
3285 /* Need a session for kernel command */
3286 if (need_tracing_session) {
3287 if (cmd_ctx->session->kernel_session == NULL) {
3288 ret = create_kernel_session(cmd_ctx->session);
3289 if (ret < 0) {
3290 ret = LTTCOMM_KERN_SESS_FAIL;
3291 goto error;
3292 }
3293 }
3294
3295 /* Start the kernel consumer daemon */
3296 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3297 if (kconsumer_data.pid == 0 &&
3298 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3299 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3300 ret = start_consumerd(&kconsumer_data);
3301 if (ret < 0) {
3302 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3303 goto error;
3304 }
3305 } else {
3306 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3307 }
3308 }
3309 break;
3310 case LTTNG_DOMAIN_UST:
3311 {
3312 if (need_tracing_session) {
3313 if (cmd_ctx->session->ust_session == NULL) {
3314 ret = create_ust_session(cmd_ctx->session,
3315 &cmd_ctx->lsm->domain);
3316 if (ret != LTTCOMM_OK) {
3317 goto error;
3318 }
3319 }
3320 /* Start the UST consumer daemons */
3321 /* 64-bit */
3322 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3323 if (consumerd64_bin[0] != '\0' &&
3324 ustconsumer64_data.pid == 0 &&
3325 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3326 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3327 ret = start_consumerd(&ustconsumer64_data);
3328 if (ret < 0) {
3329 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3330 ust_consumerd64_fd = -EINVAL;
3331 goto error;
3332 }
3333
3334 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3335 } else {
3336 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex