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Update lttng-ust header copy for disabled UST compilation
[lttng-tools.git] / src / bin / lttng-sessiond / main.c
... / ...
CommitLineData
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
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19#define _GNU_SOURCE
20#include <getopt.h>
21#include <grp.h>
22#include <limits.h>
23#include <pthread.h>
24#include <semaphore.h>
25#include <signal.h>
26#include <stdio.h>
27#include <stdlib.h>
28#include <string.h>
29#include <sys/mman.h>
30#include <sys/mount.h>
31#include <sys/resource.h>
32#include <sys/socket.h>
33#include <sys/stat.h>
34#include <sys/types.h>
35#include <sys/wait.h>
36#include <urcu/uatomic.h>
37#include <unistd.h>
38#include <config.h>
39
40#include <common/common.h>
41#include <common/compat/poll.h>
42#include <common/compat/socket.h>
43#include <common/defaults.h>
44#include <common/kernel-consumer/kernel-consumer.h>
45#include <common/ust-consumer/ust-consumer.h>
46#include <common/futex.h>
47
48#include "lttng-sessiond.h"
49#include "channel.h"
50#include "context.h"
51#include "event.h"
52#include "kernel.h"
53#include "modprobe.h"
54#include "shm.h"
55#include "ust-ctl.h"
56#include "utils.h"
57#include "fd-limit.h"
58
59#define CONSUMERD_FILE "lttng-consumerd"
60
61struct consumer_data {
62 enum lttng_consumer_type type;
63
64 pthread_t thread; /* Worker thread interacting with the consumer */
65 sem_t sem;
66
67 /* Mutex to control consumerd pid assignation */
68 pthread_mutex_t pid_mutex;
69 pid_t pid;
70
71 int err_sock;
72 int cmd_sock;
73
74 /* consumer error and command Unix socket path */
75 char err_unix_sock_path[PATH_MAX];
76 char cmd_unix_sock_path[PATH_MAX];
77};
78
79/* Const values */
80const char default_home_dir[] = DEFAULT_HOME_DIR;
81const char default_tracing_group[] = DEFAULT_TRACING_GROUP;
82const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
83const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
84
85const char *progname;
86const char *opt_tracing_group;
87static int opt_sig_parent;
88static int opt_verbose_consumer;
89static int opt_daemon;
90static int opt_no_kernel;
91static int is_root; /* Set to 1 if the daemon is running as root */
92static pid_t ppid; /* Parent PID for --sig-parent option */
93static char *rundir;
94
95/* Consumer daemon specific control data */
96static struct consumer_data kconsumer_data = {
97 .type = LTTNG_CONSUMER_KERNEL,
98 .err_unix_sock_path = DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
99 .cmd_unix_sock_path = DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
100 .err_sock = -1,
101 .cmd_sock = -1,
102};
103static struct consumer_data ustconsumer64_data = {
104 .type = LTTNG_CONSUMER64_UST,
105 .err_unix_sock_path = DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
106 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
107 .err_sock = -1,
108 .cmd_sock = -1,
109};
110static struct consumer_data ustconsumer32_data = {
111 .type = LTTNG_CONSUMER32_UST,
112 .err_unix_sock_path = DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
113 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
114 .err_sock = -1,
115 .cmd_sock = -1,
116};
117
118static int dispatch_thread_exit;
119
120/* Global application Unix socket path */
121static char apps_unix_sock_path[PATH_MAX];
122/* Global client Unix socket path */
123static char client_unix_sock_path[PATH_MAX];
124/* global wait shm path for UST */
125static char wait_shm_path[PATH_MAX];
126
127/* Sockets and FDs */
128static int client_sock = -1;
129static int apps_sock = -1;
130static int kernel_tracer_fd = -1;
131static int kernel_poll_pipe[2] = { -1, -1 };
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 */
137static int thread_quit_pipe[2] = { -1, -1 };
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 */
143static int apps_cmd_pipe[2] = { -1, -1 };
144
145/* Pthread, Mutexes and Semaphores */
146static pthread_t apps_thread;
147static pthread_t reg_apps_thread;
148static pthread_t client_thread;
149static pthread_t kernel_thread;
150static 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 */
160static 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 */
172static struct ltt_session_list *session_list_ptr;
173
174int ust_consumerd64_fd = -1;
175int ust_consumerd32_fd = -1;
176
177static const char *consumerd32_bin = CONFIG_CONSUMERD32_BIN;
178static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
179static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
180static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
181
182/*
183 * Consumer daemon state which is changed when spawning it, killing it or in
184 * case of a fatal error.
185 */
186enum consumerd_state {
187 CONSUMER_STARTED = 1,
188 CONSUMER_STOPPED = 2,
189 CONSUMER_ERROR = 3,
190};
191
192/*
193 * This consumer daemon state is used to validate if a client command will be
194 * able to reach the consumer. If not, the client is informed. For instance,
195 * doing a "lttng start" when the consumer state is set to ERROR will return an
196 * error to the client.
197 *
198 * The following example shows a possible race condition of this scheme:
199 *
200 * consumer thread error happens
201 * client cmd arrives
202 * client cmd checks state -> still OK
203 * consumer thread exit, sets error
204 * client cmd try to talk to consumer
205 * ...
206 *
207 * However, since the consumer is a different daemon, we have no way of making
208 * sure the command will reach it safely even with this state flag. This is why
209 * we consider that up to the state validation during command processing, the
210 * command is safe. After that, we can not guarantee the correctness of the
211 * client request vis-a-vis the consumer.
212 */
213static enum consumerd_state ust_consumerd_state;
214static enum consumerd_state kernel_consumerd_state;
215
216static
217void setup_consumerd_path(void)
218{
219 const char *bin, *libdir;
220
221 /*
222 * Allow INSTALL_BIN_PATH to be used as a target path for the
223 * native architecture size consumer if CONFIG_CONSUMER*_PATH
224 * has not been defined.
225 */
226#if (CAA_BITS_PER_LONG == 32)
227 if (!consumerd32_bin[0]) {
228 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
229 }
230 if (!consumerd32_libdir[0]) {
231 consumerd32_libdir = INSTALL_LIB_PATH;
232 }
233#elif (CAA_BITS_PER_LONG == 64)
234 if (!consumerd64_bin[0]) {
235 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
236 }
237 if (!consumerd64_libdir[0]) {
238 consumerd64_libdir = INSTALL_LIB_PATH;
239 }
240#else
241#error "Unknown bitness"
242#endif
243
244 /*
245 * runtime env. var. overrides the build default.
246 */
247 bin = getenv("LTTNG_CONSUMERD32_BIN");
248 if (bin) {
249 consumerd32_bin = bin;
250 }
251 bin = getenv("LTTNG_CONSUMERD64_BIN");
252 if (bin) {
253 consumerd64_bin = bin;
254 }
255 libdir = getenv("LTTNG_CONSUMERD32_LIBDIR");
256 if (libdir) {
257 consumerd32_libdir = libdir;
258 }
259 libdir = getenv("LTTNG_CONSUMERD64_LIBDIR");
260 if (libdir) {
261 consumerd64_libdir = libdir;
262 }
263}
264
265/*
266 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
267 */
268static int create_thread_poll_set(struct lttng_poll_event *events,
269 unsigned int size)
270{
271 int ret;
272
273 if (events == NULL || size == 0) {
274 ret = -1;
275 goto error;
276 }
277
278 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
279 if (ret < 0) {
280 goto error;
281 }
282
283 /* Add quit pipe */
284 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
285 if (ret < 0) {
286 goto error;
287 }
288
289 return 0;
290
291error:
292 return ret;
293}
294
295/*
296 * Check if the thread quit pipe was triggered.
297 *
298 * Return 1 if it was triggered else 0;
299 */
300static int check_thread_quit_pipe(int fd, uint32_t events)
301{
302 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
303 return 1;
304 }
305
306 return 0;
307}
308
309/*
310 * Return group ID of the tracing group or -1 if not found.
311 */
312static gid_t allowed_group(void)
313{
314 struct group *grp;
315
316 if (opt_tracing_group) {
317 grp = getgrnam(opt_tracing_group);
318 } else {
319 grp = getgrnam(default_tracing_group);
320 }
321 if (!grp) {
322 return -1;
323 } else {
324 return grp->gr_gid;
325 }
326}
327
328/*
329 * Init thread quit pipe.
330 *
331 * Return -1 on error or 0 if all pipes are created.
332 */
333static int init_thread_quit_pipe(void)
334{
335 int ret, i;
336
337 ret = pipe(thread_quit_pipe);
338 if (ret < 0) {
339 PERROR("thread quit pipe");
340 goto error;
341 }
342
343 for (i = 0; i < 2; i++) {
344 ret = fcntl(thread_quit_pipe[i], F_SETFD, FD_CLOEXEC);
345 if (ret < 0) {
346 PERROR("fcntl");
347 goto error;
348 }
349 }
350
351error:
352 return ret;
353}
354
355/*
356 * Complete teardown of a kernel session. This free all data structure related
357 * to a kernel session and update counter.
358 */
359static void teardown_kernel_session(struct ltt_session *session)
360{
361 if (!session->kernel_session) {
362 DBG3("No kernel session when tearing down session");
363 return;
364 }
365
366 DBG("Tearing down kernel session");
367
368 /*
369 * If a custom kernel consumer was registered, close the socket before
370 * tearing down the complete kernel session structure
371 */
372 if (kconsumer_data.cmd_sock >= 0 &&
373 session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
374 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
375 }
376
377 trace_kernel_destroy_session(session->kernel_session);
378}
379
380/*
381 * Complete teardown of all UST sessions. This will free everything on his path
382 * and destroy the core essence of all ust sessions :)
383 */
384static void teardown_ust_session(struct ltt_session *session)
385{
386 int ret;
387
388 if (!session->ust_session) {
389 DBG3("No UST session when tearing down session");
390 return;
391 }
392
393 DBG("Tearing down UST session(s)");
394
395 ret = ust_app_destroy_trace_all(session->ust_session);
396 if (ret) {
397 ERR("Error in ust_app_destroy_trace_all");
398 }
399
400 trace_ust_destroy_session(session->ust_session);
401}
402
403/*
404 * Stop all threads by closing the thread quit pipe.
405 */
406static void stop_threads(void)
407{
408 int ret;
409
410 /* Stopping all threads */
411 DBG("Terminating all threads");
412 ret = notify_thread_pipe(thread_quit_pipe[1]);
413 if (ret < 0) {
414 ERR("write error on thread quit pipe");
415 }
416
417 /* Dispatch thread */
418 dispatch_thread_exit = 1;
419 futex_nto1_wake(&ust_cmd_queue.futex);
420}
421
422/*
423 * Cleanup the daemon
424 */
425static void cleanup(void)
426{
427 int ret, i;
428 char *cmd;
429 struct ltt_session *sess, *stmp;
430
431 DBG("Cleaning up");
432
433 DBG("Removing %s directory", rundir);
434 ret = asprintf(&cmd, "rm -rf %s", rundir);
435 if (ret < 0) {
436 ERR("asprintf failed. Something is really wrong!");
437 }
438
439 /* Remove lttng run directory */
440 ret = system(cmd);
441 if (ret < 0) {
442 ERR("Unable to clean %s", rundir);
443 }
444 free(cmd);
445
446 DBG("Cleaning up all sessions");
447
448 /* Destroy session list mutex */
449 if (session_list_ptr != NULL) {
450 pthread_mutex_destroy(&session_list_ptr->lock);
451
452 /* Cleanup ALL session */
453 cds_list_for_each_entry_safe(sess, stmp,
454 &session_list_ptr->head, list) {
455 teardown_kernel_session(sess);
456 teardown_ust_session(sess);
457 free(sess);
458 }
459 }
460
461 DBG("Closing all UST sockets");
462 ust_app_clean_list();
463
464 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
465
466 if (is_root && !opt_no_kernel) {
467 DBG2("Closing kernel fd");
468 if (kernel_tracer_fd >= 0) {
469 ret = close(kernel_tracer_fd);
470 if (ret) {
471 PERROR("close");
472 }
473 }
474 DBG("Unloading kernel modules");
475 modprobe_remove_lttng_all();
476 }
477
478 /*
479 * Closing all pipes used for communication between threads.
480 */
481 for (i = 0; i < 2; i++) {
482 if (kernel_poll_pipe[i] >= 0) {
483 ret = close(kernel_poll_pipe[i]);
484 if (ret) {
485 PERROR("close");
486 }
487 }
488 }
489 for (i = 0; i < 2; i++) {
490 if (thread_quit_pipe[i] >= 0) {
491 ret = close(thread_quit_pipe[i]);
492 if (ret) {
493 PERROR("close");
494 }
495 }
496 }
497 for (i = 0; i < 2; i++) {
498 if (apps_cmd_pipe[i] >= 0) {
499 ret = close(apps_cmd_pipe[i]);
500 if (ret) {
501 PERROR("close");
502 }
503 }
504 }
505
506 /* <fun> */
507 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
508 "Matthew, BEET driven development works!%c[%dm",
509 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
510 /* </fun> */
511}
512
513/*
514 * Send data on a unix socket using the liblttsessiondcomm API.
515 *
516 * Return lttcomm error code.
517 */
518static int send_unix_sock(int sock, void *buf, size_t len)
519{
520 /* Check valid length */
521 if (len <= 0) {
522 return -1;
523 }
524
525 return lttcomm_send_unix_sock(sock, buf, len);
526}
527
528/*
529 * Free memory of a command context structure.
530 */
531static void clean_command_ctx(struct command_ctx **cmd_ctx)
532{
533 DBG("Clean command context structure");
534 if (*cmd_ctx) {
535 if ((*cmd_ctx)->llm) {
536 free((*cmd_ctx)->llm);
537 }
538 if ((*cmd_ctx)->lsm) {
539 free((*cmd_ctx)->lsm);
540 }
541 free(*cmd_ctx);
542 *cmd_ctx = NULL;
543 }
544}
545
546/*
547 * Send all stream fds of kernel channel to the consumer.
548 */
549static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
550 int sock, struct ltt_kernel_channel *channel,
551 uid_t uid, gid_t gid)
552{
553 int ret;
554 struct ltt_kernel_stream *stream;
555 struct lttcomm_consumer_msg lkm;
556
557 DBG("Sending streams of channel %s to kernel consumer",
558 channel->channel->name);
559
560 /* Send channel */
561 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
562 lkm.u.channel.channel_key = channel->fd;
563 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
564 lkm.u.channel.mmap_len = 0; /* for kernel */
565 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
566 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
567 if (ret < 0) {
568 PERROR("send consumer channel");
569 goto error;
570 }
571
572 /* Send streams */
573 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
574 if (!stream->fd) {
575 continue;
576 }
577 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
578 lkm.u.stream.channel_key = channel->fd;
579 lkm.u.stream.stream_key = stream->fd;
580 lkm.u.stream.state = stream->state;
581 lkm.u.stream.output = channel->channel->attr.output;
582 lkm.u.stream.mmap_len = 0; /* for kernel */
583 lkm.u.stream.uid = uid;
584 lkm.u.stream.gid = gid;
585 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
586 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
587 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
588 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
589 if (ret < 0) {
590 PERROR("send consumer stream");
591 goto error;
592 }
593 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
594 if (ret < 0) {
595 PERROR("send consumer stream ancillary data");
596 goto error;
597 }
598 }
599
600 DBG("consumer channel streams sent");
601
602 return 0;
603
604error:
605 return ret;
606}
607
608/*
609 * Send all stream fds of the kernel session to the consumer.
610 */
611static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
612 struct ltt_kernel_session *session)
613{
614 int ret;
615 struct ltt_kernel_channel *chan;
616 struct lttcomm_consumer_msg lkm;
617 int sock = session->consumer_fd;
618
619 DBG("Sending metadata stream fd");
620
621 /* Extra protection. It's NOT supposed to be set to -1 at this point */
622 if (session->consumer_fd < 0) {
623 session->consumer_fd = consumer_data->cmd_sock;
624 }
625
626 if (session->metadata_stream_fd >= 0) {
627 /* Send metadata channel fd */
628 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
629 lkm.u.channel.channel_key = session->metadata->fd;
630 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
631 lkm.u.channel.mmap_len = 0; /* for kernel */
632 DBG("Sending metadata channel %d to consumer", lkm.u.channel.channel_key);
633 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
634 if (ret < 0) {
635 PERROR("send consumer channel");
636 goto error;
637 }
638
639 /* Send metadata stream fd */
640 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
641 lkm.u.stream.channel_key = session->metadata->fd;
642 lkm.u.stream.stream_key = session->metadata_stream_fd;
643 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
644 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
645 lkm.u.stream.mmap_len = 0; /* for kernel */
646 lkm.u.stream.uid = session->uid;
647 lkm.u.stream.gid = session->gid;
648 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
649 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
650 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
651 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
652 if (ret < 0) {
653 PERROR("send consumer stream");
654 goto error;
655 }
656 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
657 if (ret < 0) {
658 PERROR("send consumer stream");
659 goto error;
660 }
661 }
662
663 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
664 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
665 session->uid, session->gid);
666 if (ret < 0) {
667 goto error;
668 }
669 }
670
671 DBG("consumer fds (metadata and channel streams) sent");
672
673 return 0;
674
675error:
676 return ret;
677}
678
679/*
680 * Notify UST applications using the shm mmap futex.
681 */
682static int notify_ust_apps(int active)
683{
684 char *wait_shm_mmap;
685
686 DBG("Notifying applications of session daemon state: %d", active);
687
688 /* See shm.c for this call implying mmap, shm and futex calls */
689 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
690 if (wait_shm_mmap == NULL) {
691 goto error;
692 }
693
694 /* Wake waiting process */
695 futex_wait_update((int32_t *) wait_shm_mmap, active);
696
697 /* Apps notified successfully */
698 return 0;
699
700error:
701 return -1;
702}
703
704/*
705 * Setup the outgoing data buffer for the response (llm) by allocating the
706 * right amount of memory and copying the original information from the lsm
707 * structure.
708 *
709 * Return total size of the buffer pointed by buf.
710 */
711static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
712{
713 int ret, buf_size;
714
715 buf_size = size;
716
717 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
718 if (cmd_ctx->llm == NULL) {
719 PERROR("zmalloc");
720 ret = -ENOMEM;
721 goto error;
722 }
723
724 /* Copy common data */
725 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
726 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
727
728 cmd_ctx->llm->data_size = size;
729 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
730
731 return buf_size;
732
733error:
734 return ret;
735}
736
737/*
738 * Update the kernel poll set of all channel fd available over all tracing
739 * session. Add the wakeup pipe at the end of the set.
740 */
741static int update_kernel_poll(struct lttng_poll_event *events)
742{
743 int ret;
744 struct ltt_session *session;
745 struct ltt_kernel_channel *channel;
746
747 DBG("Updating kernel poll set");
748
749 session_lock_list();
750 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
751 session_lock(session);
752 if (session->kernel_session == NULL) {
753 session_unlock(session);
754 continue;
755 }
756
757 cds_list_for_each_entry(channel,
758 &session->kernel_session->channel_list.head, list) {
759 /* Add channel fd to the kernel poll set */
760 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
761 if (ret < 0) {
762 session_unlock(session);
763 goto error;
764 }
765 DBG("Channel fd %d added to kernel set", channel->fd);
766 }
767 session_unlock(session);
768 }
769 session_unlock_list();
770
771 return 0;
772
773error:
774 session_unlock_list();
775 return -1;
776}
777
778/*
779 * Find the channel fd from 'fd' over all tracing session. When found, check
780 * for new channel stream and send those stream fds to the kernel consumer.
781 *
782 * Useful for CPU hotplug feature.
783 */
784static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
785{
786 int ret = 0;
787 struct ltt_session *session;
788 struct ltt_kernel_channel *channel;
789
790 DBG("Updating kernel streams for channel fd %d", fd);
791
792 session_lock_list();
793 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
794 session_lock(session);
795 if (session->kernel_session == NULL) {
796 session_unlock(session);
797 continue;
798 }
799
800 /* This is not suppose to be -1 but this is an extra security check */
801 if (session->kernel_session->consumer_fd < 0) {
802 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
803 }
804
805 cds_list_for_each_entry(channel,
806 &session->kernel_session->channel_list.head, list) {
807 if (channel->fd == fd) {
808 DBG("Channel found, updating kernel streams");
809 ret = kernel_open_channel_stream(channel);
810 if (ret < 0) {
811 goto error;
812 }
813
814 /*
815 * Have we already sent fds to the consumer? If yes, it means
816 * that tracing is started so it is safe to send our updated
817 * stream fds.
818 */
819 if (session->kernel_session->consumer_fds_sent == 1) {
820 ret = send_kconsumer_channel_streams(consumer_data,
821 session->kernel_session->consumer_fd, channel,
822 session->uid, session->gid);
823 if (ret < 0) {
824 goto error;
825 }
826 }
827 goto error;
828 }
829 }
830 session_unlock(session);
831 }
832 session_unlock_list();
833 return ret;
834
835error:
836 session_unlock(session);
837 session_unlock_list();
838 return ret;
839}
840
841/*
842 * For each tracing session, update newly registered apps.
843 */
844static void update_ust_app(int app_sock)
845{
846 struct ltt_session *sess, *stmp;
847
848 session_lock_list();
849
850 /* For all tracing session(s) */
851 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
852 session_lock(sess);
853 if (sess->ust_session) {
854 ust_app_global_update(sess->ust_session, app_sock);
855 }
856 session_unlock(sess);
857 }
858
859 session_unlock_list();
860}
861
862/*
863 * This thread manage event coming from the kernel.
864 *
865 * Features supported in this thread:
866 * -) CPU Hotplug
867 */
868static void *thread_manage_kernel(void *data)
869{
870 int ret, i, pollfd, update_poll_flag = 1;
871 uint32_t revents, nb_fd;
872 char tmp;
873 struct lttng_poll_event events;
874
875 DBG("Thread manage kernel started");
876
877 ret = create_thread_poll_set(&events, 2);
878 if (ret < 0) {
879 goto error_poll_create;
880 }
881
882 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
883 if (ret < 0) {
884 goto error;
885 }
886
887 while (1) {
888 if (update_poll_flag == 1) {
889 /*
890 * Reset number of fd in the poll set. Always 2 since there is the thread
891 * quit pipe and the kernel pipe.
892 */
893 events.nb_fd = 2;
894
895 ret = update_kernel_poll(&events);
896 if (ret < 0) {
897 goto error;
898 }
899 update_poll_flag = 0;
900 }
901
902 nb_fd = LTTNG_POLL_GETNB(&events);
903
904 DBG("Thread kernel polling on %d fds", nb_fd);
905
906 /* Zeroed the poll events */
907 lttng_poll_reset(&events);
908
909 /* Poll infinite value of time */
910 restart:
911 ret = lttng_poll_wait(&events, -1);
912 if (ret < 0) {
913 /*
914 * Restart interrupted system call.
915 */
916 if (errno == EINTR) {
917 goto restart;
918 }
919 goto error;
920 } else if (ret == 0) {
921 /* Should not happen since timeout is infinite */
922 ERR("Return value of poll is 0 with an infinite timeout.\n"
923 "This should not have happened! Continuing...");
924 continue;
925 }
926
927 for (i = 0; i < nb_fd; i++) {
928 /* Fetch once the poll data */
929 revents = LTTNG_POLL_GETEV(&events, i);
930 pollfd = LTTNG_POLL_GETFD(&events, i);
931
932 /* Thread quit pipe has been closed. Killing thread. */
933 ret = check_thread_quit_pipe(pollfd, revents);
934 if (ret) {
935 goto error;
936 }
937
938 /* Check for data on kernel pipe */
939 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
940 ret = read(kernel_poll_pipe[0], &tmp, 1);
941 update_poll_flag = 1;
942 continue;
943 } else {
944 /*
945 * New CPU detected by the kernel. Adding kernel stream to
946 * kernel session and updating the kernel consumer
947 */
948 if (revents & LPOLLIN) {
949 ret = update_kernel_stream(&kconsumer_data, pollfd);
950 if (ret < 0) {
951 continue;
952 }
953 break;
954 /*
955 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
956 * and unregister kernel stream at this point.
957 */
958 }
959 }
960 }
961 }
962
963error:
964 lttng_poll_clean(&events);
965error_poll_create:
966 DBG("Kernel thread dying");
967 return NULL;
968}
969
970/*
971 * This thread manage the consumer error sent back to the session daemon.
972 */
973static void *thread_manage_consumer(void *data)
974{
975 int sock = -1, i, ret, pollfd;
976 uint32_t revents, nb_fd;
977 enum lttcomm_return_code code;
978 struct lttng_poll_event events;
979 struct consumer_data *consumer_data = data;
980
981 DBG("[thread] Manage consumer started");
982
983 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
984 if (ret < 0) {
985 goto error_listen;
986 }
987
988 /*
989 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
990 * Nothing more will be added to this poll set.
991 */
992 ret = create_thread_poll_set(&events, 2);
993 if (ret < 0) {
994 goto error_poll;
995 }
996
997 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
998 if (ret < 0) {
999 goto error;
1000 }
1001
1002 nb_fd = LTTNG_POLL_GETNB(&events);
1003
1004 /* Inifinite blocking call, waiting for transmission */
1005restart:
1006 ret = lttng_poll_wait(&events, -1);
1007 if (ret < 0) {
1008 /*
1009 * Restart interrupted system call.
1010 */
1011 if (errno == EINTR) {
1012 goto restart;
1013 }
1014 goto error;
1015 }
1016
1017 for (i = 0; i < nb_fd; i++) {
1018 /* Fetch once the poll data */
1019 revents = LTTNG_POLL_GETEV(&events, i);
1020 pollfd = LTTNG_POLL_GETFD(&events, i);
1021
1022 /* Thread quit pipe has been closed. Killing thread. */
1023 ret = check_thread_quit_pipe(pollfd, revents);
1024 if (ret) {
1025 goto error;
1026 }
1027
1028 /* Event on the registration socket */
1029 if (pollfd == consumer_data->err_sock) {
1030 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1031 ERR("consumer err socket poll error");
1032 goto error;
1033 }
1034 }
1035 }
1036
1037 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
1038 if (sock < 0) {
1039 goto error;
1040 }
1041
1042 DBG2("Receiving code from consumer err_sock");
1043
1044 /* Getting status code from kconsumerd */
1045 ret = lttcomm_recv_unix_sock(sock, &code,
1046 sizeof(enum lttcomm_return_code));
1047 if (ret <= 0) {
1048 goto error;
1049 }
1050
1051 if (code == CONSUMERD_COMMAND_SOCK_READY) {
1052 consumer_data->cmd_sock =
1053 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
1054 if (consumer_data->cmd_sock < 0) {
1055 sem_post(&consumer_data->sem);
1056 PERROR("consumer connect");
1057 goto error;
1058 }
1059 /* Signal condition to tell that the kconsumerd is ready */
1060 sem_post(&consumer_data->sem);
1061 DBG("consumer command socket ready");
1062 } else {
1063 ERR("consumer error when waiting for SOCK_READY : %s",
1064 lttcomm_get_readable_code(-code));
1065 goto error;
1066 }
1067
1068 /* Remove the kconsumerd error sock since we've established a connexion */
1069 ret = lttng_poll_del(&events, consumer_data->err_sock);
1070 if (ret < 0) {
1071 goto error;
1072 }
1073
1074 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1075 if (ret < 0) {
1076 goto error;
1077 }
1078
1079 /* Update number of fd */
1080 nb_fd = LTTNG_POLL_GETNB(&events);
1081
1082 /* Inifinite blocking call, waiting for transmission */
1083restart_poll:
1084 ret = lttng_poll_wait(&events, -1);
1085 if (ret < 0) {
1086 /*
1087 * Restart interrupted system call.
1088 */
1089 if (errno == EINTR) {
1090 goto restart_poll;
1091 }
1092 goto error;
1093 }
1094
1095 for (i = 0; i < nb_fd; i++) {
1096 /* Fetch once the poll data */
1097 revents = LTTNG_POLL_GETEV(&events, i);
1098 pollfd = LTTNG_POLL_GETFD(&events, i);
1099
1100 /* Thread quit pipe has been closed. Killing thread. */
1101 ret = check_thread_quit_pipe(pollfd, revents);
1102 if (ret) {
1103 goto error;
1104 }
1105
1106 /* Event on the kconsumerd socket */
1107 if (pollfd == sock) {
1108 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1109 ERR("consumer err socket second poll error");
1110 goto error;
1111 }
1112 }
1113 }
1114
1115 /* Wait for any kconsumerd error */
1116 ret = lttcomm_recv_unix_sock(sock, &code,
1117 sizeof(enum lttcomm_return_code));
1118 if (ret <= 0) {
1119 ERR("consumer closed the command socket");
1120 goto error;
1121 }
1122
1123 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1124
1125error:
1126 /* Immediately set the consumerd state to stopped */
1127 if (consumer_data->type == LTTNG_CONSUMER_KERNEL) {
1128 uatomic_set(&kernel_consumerd_state, CONSUMER_ERROR);
1129 } else if (consumer_data->type == LTTNG_CONSUMER64_UST ||
1130 consumer_data->type == LTTNG_CONSUMER32_UST) {
1131 uatomic_set(&ust_consumerd_state, CONSUMER_ERROR);
1132 } else {
1133 /* Code flow error... */
1134 assert(0);
1135 }
1136
1137 if (consumer_data->err_sock >= 0) {
1138 ret = close(consumer_data->err_sock);
1139 if (ret) {
1140 PERROR("close");
1141 }
1142 }
1143 if (consumer_data->cmd_sock >= 0) {
1144 ret = close(consumer_data->cmd_sock);
1145 if (ret) {
1146 PERROR("close");
1147 }
1148 }
1149 if (sock >= 0) {
1150 ret = close(sock);
1151 if (ret) {
1152 PERROR("close");
1153 }
1154 }
1155
1156 unlink(consumer_data->err_unix_sock_path);
1157 unlink(consumer_data->cmd_unix_sock_path);
1158 consumer_data->pid = 0;
1159
1160 lttng_poll_clean(&events);
1161error_poll:
1162error_listen:
1163 DBG("consumer thread cleanup completed");
1164
1165 return NULL;
1166}
1167
1168/*
1169 * This thread manage application communication.
1170 */
1171static void *thread_manage_apps(void *data)
1172{
1173 int i, ret, pollfd;
1174 uint32_t revents, nb_fd;
1175 struct ust_command ust_cmd;
1176 struct lttng_poll_event events;
1177
1178 DBG("[thread] Manage application started");
1179
1180 rcu_register_thread();
1181 rcu_thread_online();
1182
1183 ret = create_thread_poll_set(&events, 2);
1184 if (ret < 0) {
1185 goto error_poll_create;
1186 }
1187
1188 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1189 if (ret < 0) {
1190 goto error;
1191 }
1192
1193 while (1) {
1194 /* Zeroed the events structure */
1195 lttng_poll_reset(&events);
1196
1197 nb_fd = LTTNG_POLL_GETNB(&events);
1198
1199 DBG("Apps thread polling on %d fds", nb_fd);
1200
1201 /* Inifinite blocking call, waiting for transmission */
1202 restart:
1203 ret = lttng_poll_wait(&events, -1);
1204 if (ret < 0) {
1205 /*
1206 * Restart interrupted system call.
1207 */
1208 if (errno == EINTR) {
1209 goto restart;
1210 }
1211 goto error;
1212 }
1213
1214 for (i = 0; i < nb_fd; i++) {
1215 /* Fetch once the poll data */
1216 revents = LTTNG_POLL_GETEV(&events, i);
1217 pollfd = LTTNG_POLL_GETFD(&events, i);
1218
1219 /* Thread quit pipe has been closed. Killing thread. */
1220 ret = check_thread_quit_pipe(pollfd, revents);
1221 if (ret) {
1222 goto error;
1223 }
1224
1225 /* Inspect the apps cmd pipe */
1226 if (pollfd == apps_cmd_pipe[0]) {
1227 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1228 ERR("Apps command pipe error");
1229 goto error;
1230 } else if (revents & LPOLLIN) {
1231 /* Empty pipe */
1232 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1233 if (ret < 0 || ret < sizeof(ust_cmd)) {
1234 PERROR("read apps cmd pipe");
1235 goto error;
1236 }
1237
1238 /* Register applicaton to the session daemon */
1239 ret = ust_app_register(&ust_cmd.reg_msg,
1240 ust_cmd.sock);
1241 if (ret == -ENOMEM) {
1242 goto error;
1243 } else if (ret < 0) {
1244 break;
1245 }
1246
1247 /*
1248 * Validate UST version compatibility.
1249 */
1250 ret = ust_app_validate_version(ust_cmd.sock);
1251 if (ret >= 0) {
1252 /*
1253 * Add channel(s) and event(s) to newly registered apps
1254 * from lttng global UST domain.
1255 */
1256 update_ust_app(ust_cmd.sock);
1257 }
1258
1259 ret = ust_app_register_done(ust_cmd.sock);
1260 if (ret < 0) {
1261 /*
1262 * If the registration is not possible, we simply
1263 * unregister the apps and continue
1264 */
1265 ust_app_unregister(ust_cmd.sock);
1266 } else {
1267 /*
1268 * We just need here to monitor the close of the UST
1269 * socket and poll set monitor those by default.
1270 * Listen on POLLIN (even if we never expect any
1271 * data) to ensure that hangup wakes us.
1272 */
1273 ret = lttng_poll_add(&events, ust_cmd.sock, LPOLLIN);
1274 if (ret < 0) {
1275 goto error;
1276 }
1277
1278 DBG("Apps with sock %d added to poll set",
1279 ust_cmd.sock);
1280 }
1281
1282 break;
1283 }
1284 } else {
1285 /*
1286 * At this point, we know that a registered application made
1287 * the event at poll_wait.
1288 */
1289 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1290 /* Removing from the poll set */
1291 ret = lttng_poll_del(&events, pollfd);
1292 if (ret < 0) {
1293 goto error;
1294 }
1295
1296 /* Socket closed on remote end. */
1297 ust_app_unregister(pollfd);
1298 break;
1299 }
1300 }
1301 }
1302 }
1303
1304error:
1305 lttng_poll_clean(&events);
1306error_poll_create:
1307 DBG("Application communication apps thread cleanup complete");
1308 rcu_thread_offline();
1309 rcu_unregister_thread();
1310 return NULL;
1311}
1312
1313/*
1314 * Dispatch request from the registration threads to the application
1315 * communication thread.
1316 */
1317static void *thread_dispatch_ust_registration(void *data)
1318{
1319 int ret;
1320 struct cds_wfq_node *node;
1321 struct ust_command *ust_cmd = NULL;
1322
1323 DBG("[thread] Dispatch UST command started");
1324
1325 while (!dispatch_thread_exit) {
1326 /* Atomically prepare the queue futex */
1327 futex_nto1_prepare(&ust_cmd_queue.futex);
1328
1329 do {
1330 /* Dequeue command for registration */
1331 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1332 if (node == NULL) {
1333 DBG("Woken up but nothing in the UST command queue");
1334 /* Continue thread execution */
1335 break;
1336 }
1337
1338 ust_cmd = caa_container_of(node, struct ust_command, node);
1339
1340 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1341 " gid:%d sock:%d name:%s (version %d.%d)",
1342 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1343 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1344 ust_cmd->sock, ust_cmd->reg_msg.name,
1345 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1346 /*
1347 * Inform apps thread of the new application registration. This
1348 * call is blocking so we can be assured that the data will be read
1349 * at some point in time or wait to the end of the world :)
1350 */
1351 ret = write(apps_cmd_pipe[1], ust_cmd,
1352 sizeof(struct ust_command));
1353 if (ret < 0) {
1354 PERROR("write apps cmd pipe");
1355 if (errno == EBADF) {
1356 /*
1357 * We can't inform the application thread to process
1358 * registration. We will exit or else application
1359 * registration will not occur and tracing will never
1360 * start.
1361 */
1362 goto error;
1363 }
1364 }
1365 free(ust_cmd);
1366 } while (node != NULL);
1367
1368 /* Futex wait on queue. Blocking call on futex() */
1369 futex_nto1_wait(&ust_cmd_queue.futex);
1370 }
1371
1372error:
1373 DBG("Dispatch thread dying");
1374 return NULL;
1375}
1376
1377/*
1378 * This thread manage application registration.
1379 */
1380static void *thread_registration_apps(void *data)
1381{
1382 int sock = -1, i, ret, pollfd;
1383 uint32_t revents, nb_fd;
1384 struct lttng_poll_event events;
1385 /*
1386 * Get allocated in this thread, enqueued to a global queue, dequeued and
1387 * freed in the manage apps thread.
1388 */
1389 struct ust_command *ust_cmd = NULL;
1390
1391 DBG("[thread] Manage application registration started");
1392
1393 ret = lttcomm_listen_unix_sock(apps_sock);
1394 if (ret < 0) {
1395 goto error_listen;
1396 }
1397
1398 /*
1399 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1400 * more will be added to this poll set.
1401 */
1402 ret = create_thread_poll_set(&events, 2);
1403 if (ret < 0) {
1404 goto error_create_poll;
1405 }
1406
1407 /* Add the application registration socket */
1408 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1409 if (ret < 0) {
1410 goto error_poll_add;
1411 }
1412
1413 /* Notify all applications to register */
1414 ret = notify_ust_apps(1);
1415 if (ret < 0) {
1416 ERR("Failed to notify applications or create the wait shared memory.\n"
1417 "Execution continues but there might be problem for already\n"
1418 "running applications that wishes to register.");
1419 }
1420
1421 while (1) {
1422 DBG("Accepting application registration");
1423
1424 nb_fd = LTTNG_POLL_GETNB(&events);
1425
1426 /* Inifinite blocking call, waiting for transmission */
1427 restart:
1428 ret = lttng_poll_wait(&events, -1);
1429 if (ret < 0) {
1430 /*
1431 * Restart interrupted system call.
1432 */
1433 if (errno == EINTR) {
1434 goto restart;
1435 }
1436 goto error;
1437 }
1438
1439 for (i = 0; i < nb_fd; i++) {
1440 /* Fetch once the poll data */
1441 revents = LTTNG_POLL_GETEV(&events, i);
1442 pollfd = LTTNG_POLL_GETFD(&events, i);
1443
1444 /* Thread quit pipe has been closed. Killing thread. */
1445 ret = check_thread_quit_pipe(pollfd, revents);
1446 if (ret) {
1447 goto error;
1448 }
1449
1450 /* Event on the registration socket */
1451 if (pollfd == apps_sock) {
1452 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1453 ERR("Register apps socket poll error");
1454 goto error;
1455 } else if (revents & LPOLLIN) {
1456 sock = lttcomm_accept_unix_sock(apps_sock);
1457 if (sock < 0) {
1458 goto error;
1459 }
1460
1461 /* Create UST registration command for enqueuing */
1462 ust_cmd = zmalloc(sizeof(struct ust_command));
1463 if (ust_cmd == NULL) {
1464 PERROR("ust command zmalloc");
1465 goto error;
1466 }
1467
1468 /*
1469 * Using message-based transmissions to ensure we don't
1470 * have to deal with partially received messages.
1471 */
1472 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
1473 if (ret < 0) {
1474 ERR("Exhausted file descriptors allowed for applications.");
1475 free(ust_cmd);
1476 ret = close(sock);
1477 if (ret) {
1478 PERROR("close");
1479 }
1480 sock = -1;
1481 continue;
1482 }
1483 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1484 sizeof(struct ust_register_msg));
1485 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1486 if (ret < 0) {
1487 PERROR("lttcomm_recv_unix_sock register apps");
1488 } else {
1489 ERR("Wrong size received on apps register");
1490 }
1491 free(ust_cmd);
1492 ret = close(sock);
1493 if (ret) {
1494 PERROR("close");
1495 }
1496 lttng_fd_put(LTTNG_FD_APPS, 1);
1497 sock = -1;
1498 continue;
1499 }
1500
1501 ust_cmd->sock = sock;
1502 sock = -1;
1503
1504 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1505 " gid:%d sock:%d name:%s (version %d.%d)",
1506 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1507 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1508 ust_cmd->sock, ust_cmd->reg_msg.name,
1509 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1510
1511 /*
1512 * Lock free enqueue the registration request. The red pill
1513 * has been taken! This apps will be part of the *system*.
1514 */
1515 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1516
1517 /*
1518 * Wake the registration queue futex. Implicit memory
1519 * barrier with the exchange in cds_wfq_enqueue.
1520 */
1521 futex_nto1_wake(&ust_cmd_queue.futex);
1522 }
1523 }
1524 }
1525 }
1526
1527error:
1528 /* Notify that the registration thread is gone */
1529 notify_ust_apps(0);
1530
1531 if (apps_sock >= 0) {
1532 ret = close(apps_sock);
1533 if (ret) {
1534 PERROR("close");
1535 }
1536 }
1537 if (sock >= 0) {
1538 ret = close(sock);
1539 if (ret) {
1540 PERROR("close");
1541 }
1542 lttng_fd_put(LTTNG_FD_APPS, 1);
1543 }
1544 unlink(apps_unix_sock_path);
1545
1546error_poll_add:
1547 lttng_poll_clean(&events);
1548error_listen:
1549error_create_poll:
1550 DBG("UST Registration thread cleanup complete");
1551
1552 return NULL;
1553}
1554
1555/*
1556 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1557 * exec or it will fails.
1558 */
1559static int spawn_consumer_thread(struct consumer_data *consumer_data)
1560{
1561 int ret;
1562 struct timespec timeout;
1563
1564 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1565 timeout.tv_nsec = 0;
1566
1567 /* Setup semaphore */
1568 ret = sem_init(&consumer_data->sem, 0, 0);
1569 if (ret < 0) {
1570 PERROR("sem_init consumer semaphore");
1571 goto error;
1572 }
1573
1574 ret = pthread_create(&consumer_data->thread, NULL,
1575 thread_manage_consumer, consumer_data);
1576 if (ret != 0) {
1577 PERROR("pthread_create consumer");
1578 ret = -1;
1579 goto error;
1580 }
1581
1582 /* Get time for sem_timedwait absolute timeout */
1583 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1584 if (ret < 0) {
1585 PERROR("clock_gettime spawn consumer");
1586 /* Infinite wait for the kconsumerd thread to be ready */
1587 ret = sem_wait(&consumer_data->sem);
1588 } else {
1589 /* Normal timeout if the gettime was successful */
1590 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1591 ret = sem_timedwait(&consumer_data->sem, &timeout);
1592 }
1593
1594 if (ret < 0) {
1595 if (errno == ETIMEDOUT) {
1596 /*
1597 * Call has timed out so we kill the kconsumerd_thread and return
1598 * an error.
1599 */
1600 ERR("The consumer thread was never ready. Killing it");
1601 ret = pthread_cancel(consumer_data->thread);
1602 if (ret < 0) {
1603 PERROR("pthread_cancel consumer thread");
1604 }
1605 } else {
1606 PERROR("semaphore wait failed consumer thread");
1607 }
1608 goto error;
1609 }
1610
1611 pthread_mutex_lock(&consumer_data->pid_mutex);
1612 if (consumer_data->pid == 0) {
1613 ERR("Kconsumerd did not start");
1614 pthread_mutex_unlock(&consumer_data->pid_mutex);
1615 goto error;
1616 }
1617 pthread_mutex_unlock(&consumer_data->pid_mutex);
1618
1619 return 0;
1620
1621error:
1622 return ret;
1623}
1624
1625/*
1626 * Join consumer thread
1627 */
1628static int join_consumer_thread(struct consumer_data *consumer_data)
1629{
1630 void *status;
1631 int ret;
1632
1633 if (consumer_data->pid != 0) {
1634 ret = kill(consumer_data->pid, SIGTERM);
1635 if (ret) {
1636 ERR("Error killing consumer daemon");
1637 return ret;
1638 }
1639 return pthread_join(consumer_data->thread, &status);
1640 } else {
1641 return 0;
1642 }
1643}
1644
1645/*
1646 * Fork and exec a consumer daemon (consumerd).
1647 *
1648 * Return pid if successful else -1.
1649 */
1650static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1651{
1652 int ret;
1653 pid_t pid;
1654 const char *consumer_to_use;
1655 const char *verbosity;
1656 struct stat st;
1657
1658 DBG("Spawning consumerd");
1659
1660 pid = fork();
1661 if (pid == 0) {
1662 /*
1663 * Exec consumerd.
1664 */
1665 if (opt_verbose_consumer) {
1666 verbosity = "--verbose";
1667 } else {
1668 verbosity = "--quiet";
1669 }
1670 switch (consumer_data->type) {
1671 case LTTNG_CONSUMER_KERNEL:
1672 /*
1673 * Find out which consumerd to execute. We will first try the
1674 * 64-bit path, then the sessiond's installation directory, and
1675 * fallback on the 32-bit one,
1676 */
1677 DBG3("Looking for a kernel consumer at these locations:");
1678 DBG3(" 1) %s", consumerd64_bin);
1679 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1680 DBG3(" 3) %s", consumerd32_bin);
1681 if (stat(consumerd64_bin, &st) == 0) {
1682 DBG3("Found location #1");
1683 consumer_to_use = consumerd64_bin;
1684 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1685 DBG3("Found location #2");
1686 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1687 } else if (stat(consumerd32_bin, &st) == 0) {
1688 DBG3("Found location #3");
1689 consumer_to_use = consumerd32_bin;
1690 } else {
1691 DBG("Could not find any valid consumerd executable");
1692 break;
1693 }
1694 DBG("Using kernel consumer at: %s", consumer_to_use);
1695 execl(consumer_to_use,
1696 "lttng-consumerd", verbosity, "-k",
1697 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1698 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1699 NULL);
1700 break;
1701 case LTTNG_CONSUMER64_UST:
1702 {
1703 char *tmpnew = NULL;
1704
1705 if (consumerd64_libdir[0] != '\0') {
1706 char *tmp;
1707 size_t tmplen;
1708
1709 tmp = getenv("LD_LIBRARY_PATH");
1710 if (!tmp) {
1711 tmp = "";
1712 }
1713 tmplen = strlen("LD_LIBRARY_PATH=")
1714 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1715 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1716 if (!tmpnew) {
1717 ret = -ENOMEM;
1718 goto error;
1719 }
1720 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1721 strcat(tmpnew, consumerd64_libdir);
1722 if (tmp[0] != '\0') {
1723 strcat(tmpnew, ":");
1724 strcat(tmpnew, tmp);
1725 }
1726 ret = putenv(tmpnew);
1727 if (ret) {
1728 ret = -errno;
1729 goto error;
1730 }
1731 }
1732 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1733 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1734 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1735 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1736 NULL);
1737 if (consumerd64_libdir[0] != '\0') {
1738 free(tmpnew);
1739 }
1740 if (ret) {
1741 goto error;
1742 }
1743 break;
1744 }
1745 case LTTNG_CONSUMER32_UST:
1746 {
1747 char *tmpnew = NULL;
1748
1749 if (consumerd32_libdir[0] != '\0') {
1750 char *tmp;
1751 size_t tmplen;
1752
1753 tmp = getenv("LD_LIBRARY_PATH");
1754 if (!tmp) {
1755 tmp = "";
1756 }
1757 tmplen = strlen("LD_LIBRARY_PATH=")
1758 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1759 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1760 if (!tmpnew) {
1761 ret = -ENOMEM;
1762 goto error;
1763 }
1764 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1765 strcat(tmpnew, consumerd32_libdir);
1766 if (tmp[0] != '\0') {
1767 strcat(tmpnew, ":");
1768 strcat(tmpnew, tmp);
1769 }
1770 ret = putenv(tmpnew);
1771 if (ret) {
1772 ret = -errno;
1773 goto error;
1774 }
1775 }
1776 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1777 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1778 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1779 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1780 NULL);
1781 if (consumerd32_libdir[0] != '\0') {
1782 free(tmpnew);
1783 }
1784 if (ret) {
1785 goto error;
1786 }
1787 break;
1788 }
1789 default:
1790 PERROR("unknown consumer type");
1791 exit(EXIT_FAILURE);
1792 }
1793 if (errno != 0) {
1794 PERROR("kernel start consumer exec");
1795 }
1796 exit(EXIT_FAILURE);
1797 } else if (pid > 0) {
1798 ret = pid;
1799 } else {
1800 PERROR("start consumer fork");
1801 ret = -errno;
1802 }
1803error:
1804 return ret;
1805}
1806
1807/*
1808 * Spawn the consumerd daemon and session daemon thread.
1809 */
1810static int start_consumerd(struct consumer_data *consumer_data)
1811{
1812 int ret;
1813
1814 pthread_mutex_lock(&consumer_data->pid_mutex);
1815 if (consumer_data->pid != 0) {
1816 pthread_mutex_unlock(&consumer_data->pid_mutex);
1817 goto end;
1818 }
1819
1820 ret = spawn_consumerd(consumer_data);
1821 if (ret < 0) {
1822 ERR("Spawning consumerd failed");
1823 pthread_mutex_unlock(&consumer_data->pid_mutex);
1824 goto error;
1825 }
1826
1827 /* Setting up the consumer_data pid */
1828 consumer_data->pid = ret;
1829 DBG2("Consumer pid %d", consumer_data->pid);
1830 pthread_mutex_unlock(&consumer_data->pid_mutex);
1831
1832 DBG2("Spawning consumer control thread");
1833 ret = spawn_consumer_thread(consumer_data);
1834 if (ret < 0) {
1835 ERR("Fatal error spawning consumer control thread");
1836 goto error;
1837 }
1838
1839end:
1840 return 0;
1841
1842error:
1843 return ret;
1844}
1845
1846/*
1847 * Check version of the lttng-modules.
1848 */
1849static int validate_lttng_modules_version(void)
1850{
1851 return kernel_validate_version(kernel_tracer_fd);
1852}
1853
1854/*
1855 * Setup necessary data for kernel tracer action.
1856 */
1857static int init_kernel_tracer(void)
1858{
1859 int ret;
1860
1861 /* Modprobe lttng kernel modules */
1862 ret = modprobe_lttng_control();
1863 if (ret < 0) {
1864 goto error;
1865 }
1866
1867 /* Open debugfs lttng */
1868 kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
1869 if (kernel_tracer_fd < 0) {
1870 DBG("Failed to open %s", module_proc_lttng);
1871 ret = -1;
1872 goto error_open;
1873 }
1874
1875 /* Validate kernel version */
1876 ret = validate_lttng_modules_version();
1877 if (ret < 0) {
1878 goto error_version;
1879 }
1880
1881 ret = modprobe_lttng_data();
1882 if (ret < 0) {
1883 goto error_modules;
1884 }
1885
1886 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1887 return 0;
1888
1889error_version:
1890 modprobe_remove_lttng_control();
1891 ret = close(kernel_tracer_fd);
1892 if (ret) {
1893 PERROR("close");
1894 }
1895 kernel_tracer_fd = -1;
1896 return LTTCOMM_KERN_VERSION;
1897
1898error_modules:
1899 ret = close(kernel_tracer_fd);
1900 if (ret) {
1901 PERROR("close");
1902 }
1903
1904error_open:
1905 modprobe_remove_lttng_control();
1906
1907error:
1908 WARN("No kernel tracer available");
1909 kernel_tracer_fd = -1;
1910 if (!is_root) {
1911 return LTTCOMM_NEED_ROOT_SESSIOND;
1912 } else {
1913 return LTTCOMM_KERN_NA;
1914 }
1915}
1916
1917/*
1918 * Init tracing by creating trace directory and sending fds kernel consumer.
1919 */
1920static int init_kernel_tracing(struct ltt_kernel_session *session)
1921{
1922 int ret = 0;
1923
1924 if (session->consumer_fds_sent == 0) {
1925 /*
1926 * Assign default kernel consumer socket if no consumer assigned to the
1927 * kernel session. At this point, it's NOT supposed to be -1 but this is
1928 * an extra security check.
1929 */
1930 if (session->consumer_fd < 0) {
1931 session->consumer_fd = kconsumer_data.cmd_sock;
1932 }
1933
1934 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1935 if (ret < 0) {
1936 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1937 goto error;
1938 }
1939
1940 session->consumer_fds_sent = 1;
1941 }
1942
1943error:
1944 return ret;
1945}
1946
1947/*
1948 * Create an UST session and add it to the session ust list.
1949 */
1950static int create_ust_session(struct ltt_session *session,
1951 struct lttng_domain *domain)
1952{
1953 struct ltt_ust_session *lus = NULL;
1954 int ret;
1955
1956 switch (domain->type) {
1957 case LTTNG_DOMAIN_UST:
1958 break;
1959 default:
1960 ret = LTTCOMM_UNKNOWN_DOMAIN;
1961 goto error;
1962 }
1963
1964 DBG("Creating UST session");
1965
1966 lus = trace_ust_create_session(session->path, session->id, domain);
1967 if (lus == NULL) {
1968 ret = LTTCOMM_UST_SESS_FAIL;
1969 goto error;
1970 }
1971
1972 ret = run_as_mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1973 session->uid, session->gid);
1974 if (ret < 0) {
1975 if (ret != -EEXIST) {
1976 ERR("Trace directory creation error");
1977 ret = LTTCOMM_UST_SESS_FAIL;
1978 goto error;
1979 }
1980 }
1981
1982 /* The domain type dictate different actions on session creation */
1983 switch (domain->type) {
1984 case LTTNG_DOMAIN_UST:
1985 /* No ustctl for the global UST domain */
1986 break;
1987 default:
1988 ERR("Unknown UST domain on create session %d", domain->type);
1989 goto error;
1990 }
1991 lus->uid = session->uid;
1992 lus->gid = session->gid;
1993 session->ust_session = lus;
1994
1995 return LTTCOMM_OK;
1996
1997error:
1998 free(lus);
1999 return ret;
2000}
2001
2002/*
2003 * Create a kernel tracer session then create the default channel.
2004 */
2005static int create_kernel_session(struct ltt_session *session)
2006{
2007 int ret;
2008
2009 DBG("Creating kernel session");
2010
2011 ret = kernel_create_session(session, kernel_tracer_fd);
2012 if (ret < 0) {
2013 ret = LTTCOMM_KERN_SESS_FAIL;
2014 goto error;
2015 }
2016
2017 /* Set kernel consumer socket fd */
2018 if (kconsumer_data.cmd_sock >= 0) {
2019 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
2020 }
2021
2022 ret = run_as_mkdir_recursive(session->kernel_session->trace_path,
2023 S_IRWXU | S_IRWXG, session->uid, session->gid);
2024 if (ret < 0) {
2025 if (ret != -EEXIST) {
2026 ERR("Trace directory creation error");
2027 goto error;
2028 }
2029 }
2030 session->kernel_session->uid = session->uid;
2031 session->kernel_session->gid = session->gid;
2032
2033error:
2034 return ret;
2035}
2036
2037/*
2038 * Check if the UID or GID match the session. Root user has access to all
2039 * sessions.
2040 */
2041static int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid)
2042{
2043 if (uid != session->uid && gid != session->gid && uid != 0) {
2044 return 0;
2045 } else {
2046 return 1;
2047 }
2048}
2049
2050static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
2051{
2052 unsigned int i = 0;
2053 struct ltt_session *session;
2054
2055 DBG("Counting number of available session for UID %d GID %d",
2056 uid, gid);
2057 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2058 /*
2059 * Only list the sessions the user can control.
2060 */
2061 if (!session_access_ok(session, uid, gid)) {
2062 continue;
2063 }
2064 i++;
2065 }
2066 return i;
2067}
2068
2069/*
2070 * Using the session list, filled a lttng_session array to send back to the
2071 * client for session listing.
2072 *
2073 * The session list lock MUST be acquired before calling this function. Use
2074 * session_lock_list() and session_unlock_list().
2075 */
2076static void list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2077 gid_t gid)
2078{
2079 unsigned int i = 0;
2080 struct ltt_session *session;
2081
2082 DBG("Getting all available session for UID %d GID %d",
2083 uid, gid);
2084 /*
2085 * Iterate over session list and append data after the control struct in
2086 * the buffer.
2087 */
2088 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2089 /*
2090 * Only list the sessions the user can control.
2091 */
2092 if (!session_access_ok(session, uid, gid)) {
2093 continue;
2094 }
2095 strncpy(sessions[i].path, session->path, PATH_MAX);
2096 sessions[i].path[PATH_MAX - 1] = '\0';
2097 strncpy(sessions[i].name, session->name, NAME_MAX);
2098 sessions[i].name[NAME_MAX - 1] = '\0';
2099 sessions[i].enabled = session->enabled;
2100 i++;
2101 }
2102}
2103
2104/*
2105 * Fill lttng_channel array of all channels.
2106 */
2107static void list_lttng_channels(int domain, struct ltt_session *session,
2108 struct lttng_channel *channels)
2109{
2110 int i = 0;
2111 struct ltt_kernel_channel *kchan;
2112
2113 DBG("Listing channels for session %s", session->name);
2114
2115 switch (domain) {
2116 case LTTNG_DOMAIN_KERNEL:
2117 /* Kernel channels */
2118 if (session->kernel_session != NULL) {
2119 cds_list_for_each_entry(kchan,
2120 &session->kernel_session->channel_list.head, list) {
2121 /* Copy lttng_channel struct to array */
2122 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2123 channels[i].enabled = kchan->enabled;
2124 i++;
2125 }
2126 }
2127 break;
2128 case LTTNG_DOMAIN_UST:
2129 {
2130 struct lttng_ht_iter iter;
2131 struct ltt_ust_channel *uchan;
2132
2133 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
2134 &iter.iter, uchan, node.node) {
2135 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2136 channels[i].attr.overwrite = uchan->attr.overwrite;
2137 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2138 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2139 channels[i].attr.switch_timer_interval =
2140 uchan->attr.switch_timer_interval;
2141 channels[i].attr.read_timer_interval =
2142 uchan->attr.read_timer_interval;
2143 channels[i].enabled = uchan->enabled;
2144 switch (uchan->attr.output) {
2145 case LTTNG_UST_MMAP:
2146 default:
2147 channels[i].attr.output = LTTNG_EVENT_MMAP;
2148 break;
2149 }
2150 i++;
2151 }
2152 break;
2153 }
2154 default:
2155 break;
2156 }
2157}
2158
2159/*
2160 * Create a list of ust global domain events.
2161 */
2162static int list_lttng_ust_global_events(char *channel_name,
2163 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2164{
2165 int i = 0, ret = 0;
2166 unsigned int nb_event = 0;
2167 struct lttng_ht_iter iter;
2168 struct lttng_ht_node_str *node;
2169 struct ltt_ust_channel *uchan;
2170 struct ltt_ust_event *uevent;
2171 struct lttng_event *tmp;
2172
2173 DBG("Listing UST global events for channel %s", channel_name);
2174
2175 rcu_read_lock();
2176
2177 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2178 node = lttng_ht_iter_get_node_str(&iter);
2179 if (node == NULL) {
2180 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2181 goto error;
2182 }
2183
2184 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2185
2186 nb_event += lttng_ht_get_count(uchan->events);
2187
2188 if (nb_event == 0) {
2189 ret = nb_event;
2190 goto error;
2191 }
2192
2193 DBG3("Listing UST global %d events", nb_event);
2194
2195 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2196 if (tmp == NULL) {
2197 ret = -LTTCOMM_FATAL;
2198 goto error;
2199 }
2200
2201 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2202 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2203 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2204 tmp[i].enabled = uevent->enabled;
2205 switch (uevent->attr.instrumentation) {
2206 case LTTNG_UST_TRACEPOINT:
2207 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2208 break;
2209 case LTTNG_UST_PROBE:
2210 tmp[i].type = LTTNG_EVENT_PROBE;
2211 break;
2212 case LTTNG_UST_FUNCTION:
2213 tmp[i].type = LTTNG_EVENT_FUNCTION;
2214 break;
2215 }
2216 tmp[i].loglevel = uevent->attr.loglevel;
2217 switch (uevent->attr.loglevel_type) {
2218 case LTTNG_UST_LOGLEVEL_ALL:
2219 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2220 break;
2221 case LTTNG_UST_LOGLEVEL_RANGE:
2222 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
2223 break;
2224 case LTTNG_UST_LOGLEVEL_SINGLE:
2225 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
2226 break;
2227 }
2228 i++;
2229 }
2230
2231 ret = nb_event;
2232 *events = tmp;
2233
2234error:
2235 rcu_read_unlock();
2236 return ret;
2237}
2238
2239/*
2240 * Fill lttng_event array of all kernel events in the channel.
2241 */
2242static int list_lttng_kernel_events(char *channel_name,
2243 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2244{
2245 int i = 0, ret;
2246 unsigned int nb_event;
2247 struct ltt_kernel_event *event;
2248 struct ltt_kernel_channel *kchan;
2249
2250 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2251 if (kchan == NULL) {
2252 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2253 goto error;
2254 }
2255
2256 nb_event = kchan->event_count;
2257
2258 DBG("Listing events for channel %s", kchan->channel->name);
2259
2260 if (nb_event == 0) {
2261 ret = nb_event;
2262 goto error;
2263 }
2264
2265 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2266 if (*events == NULL) {
2267 ret = LTTCOMM_FATAL;
2268 goto error;
2269 }
2270
2271 /* Kernel channels */
2272 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2273 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2274 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2275 (*events)[i].enabled = event->enabled;
2276 switch (event->event->instrumentation) {
2277 case LTTNG_KERNEL_TRACEPOINT:
2278 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2279 break;
2280 case LTTNG_KERNEL_KPROBE:
2281 case LTTNG_KERNEL_KRETPROBE:
2282 (*events)[i].type = LTTNG_EVENT_PROBE;
2283 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2284 sizeof(struct lttng_kernel_kprobe));
2285 break;
2286 case LTTNG_KERNEL_FUNCTION:
2287 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2288 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2289 sizeof(struct lttng_kernel_function));
2290 break;
2291 case LTTNG_KERNEL_NOOP:
2292 (*events)[i].type = LTTNG_EVENT_NOOP;
2293 break;
2294 case LTTNG_KERNEL_SYSCALL:
2295 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2296 break;
2297 case LTTNG_KERNEL_ALL:
2298 assert(0);
2299 break;
2300 }
2301 i++;
2302 }
2303
2304 return nb_event;
2305
2306error:
2307 return ret;
2308}
2309
2310/*
2311 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2312 */
2313static int cmd_disable_channel(struct ltt_session *session,
2314 int domain, char *channel_name)
2315{
2316 int ret;
2317 struct ltt_ust_session *usess;
2318
2319 usess = session->ust_session;
2320
2321 switch (domain) {
2322 case LTTNG_DOMAIN_KERNEL:
2323 {
2324 ret = channel_kernel_disable(session->kernel_session,
2325 channel_name);
2326 if (ret != LTTCOMM_OK) {
2327 goto error;
2328 }
2329
2330 kernel_wait_quiescent(kernel_tracer_fd);
2331 break;
2332 }
2333 case LTTNG_DOMAIN_UST:
2334 {
2335 struct ltt_ust_channel *uchan;
2336 struct lttng_ht *chan_ht;
2337
2338 chan_ht = usess->domain_global.channels;
2339
2340 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2341 if (uchan == NULL) {
2342 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2343 goto error;
2344 }
2345
2346 ret = channel_ust_disable(usess, domain, uchan);
2347 if (ret != LTTCOMM_OK) {
2348 goto error;
2349 }
2350 break;
2351 }
2352#if 0
2353 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2354 case LTTNG_DOMAIN_UST_EXEC_NAME:
2355 case LTTNG_DOMAIN_UST_PID:
2356#endif
2357 default:
2358 ret = LTTCOMM_UNKNOWN_DOMAIN;
2359 goto error;
2360 }
2361
2362 ret = LTTCOMM_OK;
2363
2364error:
2365 return ret;
2366}
2367
2368/*
2369 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2370 */
2371static int cmd_enable_channel(struct ltt_session *session,
2372 int domain, struct lttng_channel *attr)
2373{
2374 int ret;
2375 struct ltt_ust_session *usess = session->ust_session;
2376 struct lttng_ht *chan_ht;
2377
2378 DBG("Enabling channel %s for session %s", attr->name, session->name);
2379
2380 switch (domain) {
2381 case LTTNG_DOMAIN_KERNEL:
2382 {
2383 struct ltt_kernel_channel *kchan;
2384
2385 kchan = trace_kernel_get_channel_by_name(attr->name,
2386 session->kernel_session);
2387 if (kchan == NULL) {
2388 ret = channel_kernel_create(session->kernel_session,
2389 attr, kernel_poll_pipe[1]);
2390 } else {
2391 ret = channel_kernel_enable(session->kernel_session, kchan);
2392 }
2393
2394 if (ret != LTTCOMM_OK) {
2395 goto error;
2396 }
2397
2398 kernel_wait_quiescent(kernel_tracer_fd);
2399 break;
2400 }
2401 case LTTNG_DOMAIN_UST:
2402 {
2403 struct ltt_ust_channel *uchan;
2404
2405 chan_ht = usess->domain_global.channels;
2406
2407 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2408 if (uchan == NULL) {
2409 ret = channel_ust_create(usess, domain, attr);
2410 } else {
2411 ret = channel_ust_enable(usess, domain, uchan);
2412 }
2413 break;
2414 }
2415#if 0
2416 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2417 case LTTNG_DOMAIN_UST_EXEC_NAME:
2418 case LTTNG_DOMAIN_UST_PID:
2419#endif
2420 default:
2421 ret = LTTCOMM_UNKNOWN_DOMAIN;
2422 goto error;
2423 }
2424
2425error:
2426 return ret;
2427}
2428
2429/*
2430 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2431 */
2432static int cmd_disable_event(struct ltt_session *session, int domain,
2433 char *channel_name, char *event_name)
2434{
2435 int ret;
2436
2437 switch (domain) {
2438 case LTTNG_DOMAIN_KERNEL:
2439 {
2440 struct ltt_kernel_channel *kchan;
2441 struct ltt_kernel_session *ksess;
2442
2443 ksess = session->kernel_session;
2444
2445 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2446 if (kchan == NULL) {
2447 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2448 goto error;
2449 }
2450
2451 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2452 if (ret != LTTCOMM_OK) {
2453 goto error;
2454 }
2455
2456 kernel_wait_quiescent(kernel_tracer_fd);
2457 break;
2458 }
2459 case LTTNG_DOMAIN_UST:
2460 {
2461 struct ltt_ust_channel *uchan;
2462 struct ltt_ust_session *usess;
2463
2464 usess = session->ust_session;
2465
2466 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2467 channel_name);
2468 if (uchan == NULL) {
2469 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2470 goto error;
2471 }
2472
2473 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2474 if (ret != LTTCOMM_OK) {
2475 goto error;
2476 }
2477
2478 DBG3("Disable UST event %s in channel %s completed", event_name,
2479 channel_name);
2480 break;
2481 }
2482#if 0
2483 case LTTNG_DOMAIN_UST_EXEC_NAME:
2484 case LTTNG_DOMAIN_UST_PID:
2485 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2486#endif
2487 default:
2488 ret = LTTCOMM_UND;
2489 goto error;
2490 }
2491
2492 ret = LTTCOMM_OK;
2493
2494error:
2495 return ret;
2496}
2497
2498/*
2499 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2500 */
2501static int cmd_disable_event_all(struct ltt_session *session, int domain,
2502 char *channel_name)
2503{
2504 int ret;
2505
2506 switch (domain) {
2507 case LTTNG_DOMAIN_KERNEL:
2508 {
2509 struct ltt_kernel_session *ksess;
2510 struct ltt_kernel_channel *kchan;
2511
2512 ksess = session->kernel_session;
2513
2514 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2515 if (kchan == NULL) {
2516 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2517 goto error;
2518 }
2519
2520 ret = event_kernel_disable_all(ksess, kchan);
2521 if (ret != LTTCOMM_OK) {
2522 goto error;
2523 }
2524
2525 kernel_wait_quiescent(kernel_tracer_fd);
2526 break;
2527 }
2528 case LTTNG_DOMAIN_UST:
2529 {
2530 struct ltt_ust_session *usess;
2531 struct ltt_ust_channel *uchan;
2532
2533 usess = session->ust_session;
2534
2535 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2536 channel_name);
2537 if (uchan == NULL) {
2538 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2539 goto error;
2540 }
2541
2542 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2543 if (ret != 0) {
2544 goto error;
2545 }
2546
2547 DBG3("Disable all UST events in channel %s completed", channel_name);
2548
2549 break;
2550 }
2551#if 0
2552 case LTTNG_DOMAIN_UST_EXEC_NAME:
2553 case LTTNG_DOMAIN_UST_PID:
2554 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2555#endif
2556 default:
2557 ret = LTTCOMM_UND;
2558 goto error;
2559 }
2560
2561 ret = LTTCOMM_OK;
2562
2563error:
2564 return ret;
2565}
2566
2567/*
2568 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2569 */
2570static int cmd_add_context(struct ltt_session *session, int domain,
2571 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2572{
2573 int ret;
2574
2575 switch (domain) {
2576 case LTTNG_DOMAIN_KERNEL:
2577 /* Add kernel context to kernel tracer */
2578 ret = context_kernel_add(session->kernel_session, ctx,
2579 event_name, channel_name);
2580 if (ret != LTTCOMM_OK) {
2581 goto error;
2582 }
2583 break;
2584 case LTTNG_DOMAIN_UST:
2585 {
2586 struct ltt_ust_session *usess = session->ust_session;
2587
2588 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2589 if (ret != LTTCOMM_OK) {
2590 goto error;
2591 }
2592 break;
2593 }
2594#if 0
2595 case LTTNG_DOMAIN_UST_EXEC_NAME:
2596 case LTTNG_DOMAIN_UST_PID:
2597 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2598#endif
2599 default:
2600 ret = LTTCOMM_UND;
2601 goto error;
2602 }
2603
2604 ret = LTTCOMM_OK;
2605
2606error:
2607 return ret;
2608}
2609
2610/*
2611 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2612 */
2613static int cmd_enable_event(struct ltt_session *session, int domain,
2614 char *channel_name, struct lttng_event *event)
2615{
2616 int ret;
2617 struct lttng_channel *attr;
2618 struct ltt_ust_session *usess = session->ust_session;
2619
2620 switch (domain) {
2621 case LTTNG_DOMAIN_KERNEL:
2622 {
2623 struct ltt_kernel_channel *kchan;
2624
2625 kchan = trace_kernel_get_channel_by_name(channel_name,
2626 session->kernel_session);
2627 if (kchan == NULL) {
2628 attr = channel_new_default_attr(domain);
2629 if (attr == NULL) {
2630 ret = LTTCOMM_FATAL;
2631 goto error;
2632 }
2633 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2634
2635 /* This call will notify the kernel thread */
2636 ret = channel_kernel_create(session->kernel_session,
2637 attr, kernel_poll_pipe[1]);
2638 if (ret != LTTCOMM_OK) {
2639 free(attr);
2640 goto error;
2641 }
2642 free(attr);
2643 }
2644
2645 /* Get the newly created kernel channel pointer */
2646 kchan = trace_kernel_get_channel_by_name(channel_name,
2647 session->kernel_session);
2648 if (kchan == NULL) {
2649 /* This sould not happen... */
2650 ret = LTTCOMM_FATAL;
2651 goto error;
2652 }
2653
2654 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2655 event);
2656 if (ret != LTTCOMM_OK) {
2657 goto error;
2658 }
2659
2660 kernel_wait_quiescent(kernel_tracer_fd);
2661 break;
2662 }
2663 case LTTNG_DOMAIN_UST:
2664 {
2665 struct lttng_channel *attr;
2666 struct ltt_ust_channel *uchan;
2667
2668 /* Get channel from global UST domain */
2669 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2670 channel_name);
2671 if (uchan == NULL) {
2672 /* Create default channel */
2673 attr = channel_new_default_attr(domain);
2674 if (attr == NULL) {
2675 ret = LTTCOMM_FATAL;
2676 goto error;
2677 }
2678 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2679 attr->name[NAME_MAX - 1] = '\0';
2680
2681 ret = channel_ust_create(usess, domain, attr);
2682 if (ret != LTTCOMM_OK) {
2683 free(attr);
2684 goto error;
2685 }
2686 free(attr);
2687
2688 /* Get the newly created channel reference back */
2689 uchan = trace_ust_find_channel_by_name(
2690 usess->domain_global.channels, channel_name);
2691 if (uchan == NULL) {
2692 /* Something is really wrong */
2693 ret = LTTCOMM_FATAL;
2694 goto error;
2695 }
2696 }
2697
2698 /* At this point, the session and channel exist on the tracer */
2699 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2700 if (ret != LTTCOMM_OK) {
2701 goto error;
2702 }
2703 break;
2704 }
2705#if 0
2706 case LTTNG_DOMAIN_UST_EXEC_NAME:
2707 case LTTNG_DOMAIN_UST_PID:
2708 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2709#endif
2710 default:
2711 ret = LTTCOMM_UND;
2712 goto error;
2713 }
2714
2715 ret = LTTCOMM_OK;
2716
2717error:
2718 return ret;
2719}
2720
2721/*
2722 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2723 */
2724static int cmd_enable_event_all(struct ltt_session *session, int domain,
2725 char *channel_name, int event_type)
2726{
2727 int ret;
2728 struct ltt_kernel_channel *kchan;
2729
2730 switch (domain) {
2731 case LTTNG_DOMAIN_KERNEL:
2732 kchan = trace_kernel_get_channel_by_name(channel_name,
2733 session->kernel_session);
2734 if (kchan == NULL) {
2735 /* This call will notify the kernel thread */
2736 ret = channel_kernel_create(session->kernel_session, NULL,
2737 kernel_poll_pipe[1]);
2738 if (ret != LTTCOMM_OK) {
2739 goto error;
2740 }
2741
2742 /* Get the newly created kernel channel pointer */
2743 kchan = trace_kernel_get_channel_by_name(channel_name,
2744 session->kernel_session);
2745 if (kchan == NULL) {
2746 /* This sould not happen... */
2747 ret = LTTCOMM_FATAL;
2748 goto error;
2749 }
2750
2751 }
2752
2753 switch (event_type) {
2754 case LTTNG_EVENT_SYSCALL:
2755 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2756 kchan, kernel_tracer_fd);
2757 break;
2758 case LTTNG_EVENT_TRACEPOINT:
2759 /*
2760 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2761 * events already registered to the channel.
2762 */
2763 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2764 kchan, kernel_tracer_fd);
2765 break;
2766 case LTTNG_EVENT_ALL:
2767 /* Enable syscalls and tracepoints */
2768 ret = event_kernel_enable_all(session->kernel_session,
2769 kchan, kernel_tracer_fd);
2770 break;
2771 default:
2772 ret = LTTCOMM_KERN_ENABLE_FAIL;
2773 goto error;
2774 }
2775
2776 /* Manage return value */
2777 if (ret != LTTCOMM_OK) {
2778 goto error;
2779 }
2780
2781 kernel_wait_quiescent(kernel_tracer_fd);
2782 break;
2783 case LTTNG_DOMAIN_UST:
2784 {
2785 struct lttng_channel *attr;
2786 struct ltt_ust_channel *uchan;
2787 struct ltt_ust_session *usess = session->ust_session;
2788
2789 /* Get channel from global UST domain */
2790 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2791 channel_name);
2792 if (uchan == NULL) {
2793 /* Create default channel */
2794 attr = channel_new_default_attr(domain);
2795 if (attr == NULL) {
2796 ret = LTTCOMM_FATAL;
2797 goto error;
2798 }
2799 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2800 attr->name[NAME_MAX - 1] = '\0';
2801
2802 /* Use the internal command enable channel */
2803 ret = channel_ust_create(usess, domain, attr);
2804 if (ret != LTTCOMM_OK) {
2805 free(attr);
2806 goto error;
2807 }
2808 free(attr);
2809
2810 /* Get the newly created channel reference back */
2811 uchan = trace_ust_find_channel_by_name(
2812 usess->domain_global.channels, channel_name);
2813 if (uchan == NULL) {
2814 /* Something is really wrong */
2815 ret = LTTCOMM_FATAL;
2816 goto error;
2817 }
2818 }
2819
2820 /* At this point, the session and channel exist on the tracer */
2821
2822 switch (event_type) {
2823 case LTTNG_EVENT_ALL:
2824 case LTTNG_EVENT_TRACEPOINT:
2825 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2826 if (ret != LTTCOMM_OK) {
2827 goto error;
2828 }
2829 break;
2830 default:
2831 ret = LTTCOMM_UST_ENABLE_FAIL;
2832 goto error;
2833 }
2834
2835 /* Manage return value */
2836 if (ret != LTTCOMM_OK) {
2837 goto error;
2838 }
2839
2840 break;
2841 }
2842#if 0
2843 case LTTNG_DOMAIN_UST_EXEC_NAME:
2844 case LTTNG_DOMAIN_UST_PID:
2845 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2846#endif
2847 default:
2848 ret = LTTCOMM_UND;
2849 goto error;
2850 }
2851
2852 ret = LTTCOMM_OK;
2853
2854error:
2855 return ret;
2856}
2857
2858/*
2859 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2860 */
2861static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2862{
2863 int ret;
2864 ssize_t nb_events = 0;
2865
2866 switch (domain) {
2867 case LTTNG_DOMAIN_KERNEL:
2868 nb_events = kernel_list_events(kernel_tracer_fd, events);
2869 if (nb_events < 0) {
2870 ret = LTTCOMM_KERN_LIST_FAIL;
2871 goto error;
2872 }
2873 break;
2874 case LTTNG_DOMAIN_UST:
2875 nb_events = ust_app_list_events(events);
2876 if (nb_events < 0) {
2877 ret = LTTCOMM_UST_LIST_FAIL;
2878 goto error;
2879 }
2880 break;
2881 default:
2882 ret = LTTCOMM_UND;
2883 goto error;
2884 }
2885
2886 return nb_events;
2887
2888error:
2889 /* Return negative value to differentiate return code */
2890 return -ret;
2891}
2892
2893/*
2894 * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
2895 */
2896static ssize_t cmd_list_tracepoint_fields(int domain,
2897 struct lttng_event_field **fields)
2898{
2899 int ret;
2900 ssize_t nb_fields = 0;
2901
2902 switch (domain) {
2903 case LTTNG_DOMAIN_UST:
2904 nb_fields = ust_app_list_event_fields(fields);
2905 if (nb_fields < 0) {
2906 ret = LTTCOMM_UST_LIST_FAIL;
2907 goto error;
2908 }
2909 break;
2910 case LTTNG_DOMAIN_KERNEL:
2911 default: /* fall-through */
2912 ret = LTTCOMM_UND;
2913 goto error;
2914 }
2915
2916 return nb_fields;
2917
2918error:
2919 /* Return negative value to differentiate return code */
2920 return -ret;
2921}
2922
2923/*
2924 * Command LTTNG_START_TRACE processed by the client thread.
2925 */
2926static int cmd_start_trace(struct ltt_session *session)
2927{
2928 int ret;
2929 struct ltt_kernel_session *ksession;
2930 struct ltt_ust_session *usess;
2931
2932 /* Short cut */
2933 ksession = session->kernel_session;
2934 usess = session->ust_session;
2935
2936 if (session->enabled) {
2937 /* Already started. */
2938 ret = LTTCOMM_TRACE_ALREADY_STARTED;
2939 goto error;
2940 }
2941
2942 session->enabled = 1;
2943
2944 /* Kernel tracing */
2945 if (ksession != NULL) {
2946 struct ltt_kernel_channel *kchan;
2947
2948 /* Open kernel metadata */
2949 if (ksession->metadata == NULL) {
2950 ret = kernel_open_metadata(ksession, ksession->trace_path);
2951 if (ret < 0) {
2952 ret = LTTCOMM_KERN_META_FAIL;
2953 goto error;
2954 }
2955 }
2956
2957 /* Open kernel metadata stream */
2958 if (ksession->metadata_stream_fd < 0) {
2959 ret = kernel_open_metadata_stream(ksession);
2960 if (ret < 0) {
2961 ERR("Kernel create metadata stream failed");
2962 ret = LTTCOMM_KERN_STREAM_FAIL;
2963 goto error;
2964 }
2965 }
2966
2967 /* For each channel */
2968 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2969 if (kchan->stream_count == 0) {
2970 ret = kernel_open_channel_stream(kchan);
2971 if (ret < 0) {
2972 ret = LTTCOMM_KERN_STREAM_FAIL;
2973 goto error;
2974 }
2975 /* Update the stream global counter */
2976 ksession->stream_count_global += ret;
2977 }
2978 }
2979
2980 /* Setup kernel consumer socket and send fds to it */
2981 ret = init_kernel_tracing(ksession);
2982 if (ret < 0) {
2983 ret = LTTCOMM_KERN_START_FAIL;
2984 goto error;
2985 }
2986
2987 /* This start the kernel tracing */
2988 ret = kernel_start_session(ksession);
2989 if (ret < 0) {
2990 ret = LTTCOMM_KERN_START_FAIL;
2991 goto error;
2992 }
2993
2994 /* Quiescent wait after starting trace */
2995 kernel_wait_quiescent(kernel_tracer_fd);
2996 }
2997
2998 /* Flag session that trace should start automatically */
2999 if (usess) {
3000 usess->start_trace = 1;
3001
3002 ret = ust_app_start_trace_all(usess);
3003 if (ret < 0) {
3004 ret = LTTCOMM_UST_START_FAIL;
3005 goto error;
3006 }
3007 }
3008
3009 ret = LTTCOMM_OK;
3010
3011error:
3012 return ret;
3013}
3014
3015/*
3016 * Command LTTNG_STOP_TRACE processed by the client thread.
3017 */
3018static int cmd_stop_trace(struct ltt_session *session)
3019{
3020 int ret;
3021 struct ltt_kernel_channel *kchan;
3022 struct ltt_kernel_session *ksession;
3023 struct ltt_ust_session *usess;
3024
3025 /* Short cut */
3026 ksession = session->kernel_session;
3027 usess = session->ust_session;
3028
3029 if (!session->enabled) {
3030 ret = LTTCOMM_TRACE_ALREADY_STOPPED;
3031 goto error;
3032 }
3033
3034 session->enabled = 0;
3035
3036 /* Kernel tracer */
3037 if (ksession != NULL) {
3038 DBG("Stop kernel tracing");
3039
3040 /* Flush all buffers before stopping */
3041 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
3042 if (ret < 0) {
3043 ERR("Kernel metadata flush failed");
3044 }
3045
3046 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
3047 ret = kernel_flush_buffer(kchan);
3048 if (ret < 0) {
3049 ERR("Kernel flush buffer error");
3050 }
3051 }
3052
3053 ret = kernel_stop_session(ksession);
3054 if (ret < 0) {
3055 ret = LTTCOMM_KERN_STOP_FAIL;
3056 goto error;
3057 }
3058
3059 kernel_wait_quiescent(kernel_tracer_fd);
3060 }
3061
3062 if (usess) {
3063 usess->start_trace = 0;
3064
3065 ret = ust_app_stop_trace_all(usess);
3066 if (ret < 0) {
3067 ret = LTTCOMM_UST_STOP_FAIL;
3068 goto error;
3069 }
3070 }
3071
3072 ret = LTTCOMM_OK;
3073
3074error:
3075 return ret;
3076}
3077
3078/*
3079 * Command LTTNG_CREATE_SESSION processed by the client thread.
3080 */
3081static int cmd_create_session(char *name, char *path, lttng_sock_cred *creds)
3082{
3083 int ret;
3084
3085 ret = session_create(name, path, LTTNG_SOCK_GET_UID_CRED(creds),
3086 LTTNG_SOCK_GET_GID_CRED(creds));
3087 if (ret != LTTCOMM_OK) {
3088 goto error;
3089 }
3090
3091 ret = LTTCOMM_OK;
3092
3093error:
3094 return ret;
3095}
3096
3097/*
3098 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3099 */
3100static int cmd_destroy_session(struct ltt_session *session, char *name)
3101{
3102 int ret;
3103
3104 /* Clean kernel session teardown */
3105 teardown_kernel_session(session);
3106 /* UST session teardown */
3107 teardown_ust_session(session);
3108
3109 /*
3110 * Must notify the kernel thread here to update it's poll setin order
3111 * to remove the channel(s)' fd just destroyed.
3112 */
3113 ret = notify_thread_pipe(kernel_poll_pipe[1]);
3114 if (ret < 0) {
3115 PERROR("write kernel poll pipe");
3116 }
3117
3118 ret = session_destroy(session);
3119
3120 return ret;
3121}
3122
3123/*
3124 * Command LTTNG_CALIBRATE processed by the client thread.
3125 */
3126static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3127{
3128 int ret;
3129
3130 switch (domain) {
3131 case LTTNG_DOMAIN_KERNEL:
3132 {
3133 struct lttng_kernel_calibrate kcalibrate;
3134
3135 kcalibrate.type = calibrate->type;
3136 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3137 if (ret < 0) {
3138 ret = LTTCOMM_KERN_ENABLE_FAIL;
3139 goto error;
3140 }
3141 break;
3142 }
3143 case LTTNG_DOMAIN_UST:
3144 {
3145 struct lttng_ust_calibrate ucalibrate;
3146
3147 ucalibrate.type = calibrate->type;
3148 ret = ust_app_calibrate_glb(&ucalibrate);
3149 if (ret < 0) {
3150 ret = LTTCOMM_UST_CALIBRATE_FAIL;
3151 goto error;
3152 }
3153 break;
3154 }
3155 default:
3156 ret = LTTCOMM_UND;
3157 goto error;
3158 }
3159
3160 ret = LTTCOMM_OK;
3161
3162error:
3163 return ret;
3164}
3165
3166/*
3167 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3168 */
3169static int cmd_register_consumer(struct ltt_session *session, int domain,
3170 char *sock_path)
3171{
3172 int ret, sock;
3173
3174 switch (domain) {
3175 case LTTNG_DOMAIN_KERNEL:
3176 /* Can't register a consumer if there is already one */
3177 if (session->kernel_session->consumer_fds_sent != 0) {
3178 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3179 goto error;
3180 }
3181
3182 sock = lttcomm_connect_unix_sock(sock_path);
3183 if (sock < 0) {
3184 ret = LTTCOMM_CONNECT_FAIL;
3185 goto error;
3186 }
3187
3188 session->kernel_session->consumer_fd = sock;
3189 break;
3190 default:
3191 /* TODO: Userspace tracing */
3192 ret = LTTCOMM_UND;
3193 goto error;
3194 }
3195
3196 ret = LTTCOMM_OK;
3197
3198error:
3199 return ret;
3200}
3201
3202/*
3203 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3204 */
3205static ssize_t cmd_list_domains(struct ltt_session *session,
3206 struct lttng_domain **domains)
3207{
3208 int ret, index = 0;
3209 ssize_t nb_dom = 0;
3210
3211 if (session->kernel_session != NULL) {
3212 DBG3("Listing domains found kernel domain");
3213 nb_dom++;
3214 }
3215
3216 if (session->ust_session != NULL) {
3217 DBG3("Listing domains found UST global domain");
3218 nb_dom++;
3219 }
3220
3221 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3222 if (*domains == NULL) {
3223 ret = -LTTCOMM_FATAL;
3224 goto error;
3225 }
3226
3227 if (session->kernel_session != NULL) {
3228 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3229 index++;
3230 }
3231
3232 if (session->ust_session != NULL) {
3233 (*domains)[index].type = LTTNG_DOMAIN_UST;
3234 index++;
3235 }
3236
3237 return nb_dom;
3238
3239error:
3240 return ret;
3241}
3242
3243/*
3244 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3245 */
3246static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3247 struct lttng_channel **channels)
3248{
3249 int ret;
3250 ssize_t nb_chan = 0;
3251
3252 switch (domain) {
3253 case LTTNG_DOMAIN_KERNEL:
3254 if (session->kernel_session != NULL) {
3255 nb_chan = session->kernel_session->channel_count;
3256 }
3257 DBG3("Number of kernel channels %zd", nb_chan);
3258 break;
3259 case LTTNG_DOMAIN_UST:
3260 if (session->ust_session != NULL) {
3261 nb_chan = lttng_ht_get_count(
3262 session->ust_session->domain_global.channels);
3263 }
3264 DBG3("Number of UST global channels %zd", nb_chan);
3265 break;
3266 default:
3267 *channels = NULL;
3268 ret = -LTTCOMM_UND;
3269 goto error;
3270 }
3271
3272 if (nb_chan > 0) {
3273 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3274 if (*channels == NULL) {
3275 ret = -LTTCOMM_FATAL;
3276 goto error;
3277 }
3278
3279 list_lttng_channels(domain, session, *channels);
3280 } else {
3281 *channels = NULL;
3282 }
3283
3284 return nb_chan;
3285
3286error:
3287 return ret;
3288}
3289
3290/*
3291 * Command LTTNG_LIST_EVENTS processed by the client thread.
3292 */
3293static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3294 char *channel_name, struct lttng_event **events)
3295{
3296 int ret = 0;
3297 ssize_t nb_event = 0;
3298
3299 switch (domain) {
3300 case LTTNG_DOMAIN_KERNEL:
3301 if (session->kernel_session != NULL) {
3302 nb_event = list_lttng_kernel_events(channel_name,
3303 session->kernel_session, events);
3304 }
3305 break;
3306 case LTTNG_DOMAIN_UST:
3307 {
3308 if (session->ust_session != NULL) {
3309 nb_event = list_lttng_ust_global_events(channel_name,
3310 &session->ust_session->domain_global, events);
3311 }
3312 break;
3313 }
3314 default:
3315 ret = -LTTCOMM_UND;
3316 goto error;
3317 }
3318
3319 ret = nb_event;
3320
3321error:
3322 return ret;
3323}
3324
3325/*
3326 * Process the command requested by the lttng client within the command
3327 * context structure. This function make sure that the return structure (llm)
3328 * is set and ready for transmission before returning.
3329 *
3330 * Return any error encountered or 0 for success.
3331 */
3332static int process_client_msg(struct command_ctx *cmd_ctx)
3333{
3334 int ret = LTTCOMM_OK;
3335 int need_tracing_session = 1;
3336 int need_domain;
3337
3338 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3339
3340 switch (cmd_ctx->lsm->cmd_type) {
3341 case LTTNG_CREATE_SESSION:
3342 case LTTNG_DESTROY_SESSION:
3343 case LTTNG_LIST_SESSIONS:
3344 case LTTNG_LIST_DOMAINS:
3345 case LTTNG_START_TRACE:
3346 case LTTNG_STOP_TRACE:
3347 need_domain = 0;
3348 break;
3349 default:
3350 need_domain = 1;
3351 }
3352
3353 if (opt_no_kernel && need_domain
3354 && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
3355 if (!is_root) {
3356 ret = LTTCOMM_NEED_ROOT_SESSIOND;
3357 } else {
3358 ret = LTTCOMM_KERN_NA;
3359 }
3360 goto error;
3361 }
3362
3363 /*
3364 * Check for command that don't needs to allocate a returned payload. We do
3365 * this here so we don't have to make the call for no payload at each
3366 * command.
3367 */
3368 switch(cmd_ctx->lsm->cmd_type) {
3369 case LTTNG_LIST_SESSIONS:
3370 case LTTNG_LIST_TRACEPOINTS:
3371 case LTTNG_LIST_TRACEPOINT_FIELDS:
3372 case LTTNG_LIST_DOMAINS:
3373 case LTTNG_LIST_CHANNELS:
3374 case LTTNG_LIST_EVENTS:
3375 break;
3376 default:
3377 /* Setup lttng message with no payload */
3378 ret = setup_lttng_msg(cmd_ctx, 0);
3379 if (ret < 0) {
3380 /* This label does not try to unlock the session */
3381 goto init_setup_error;
3382 }
3383 }
3384
3385 /* Commands that DO NOT need a session. */
3386 switch (cmd_ctx->lsm->cmd_type) {
3387 case LTTNG_CREATE_SESSION:
3388 case LTTNG_CALIBRATE:
3389 case LTTNG_LIST_SESSIONS:
3390 case LTTNG_LIST_TRACEPOINTS:
3391 case LTTNG_LIST_TRACEPOINT_FIELDS:
3392 need_tracing_session = 0;
3393 break;
3394 default:
3395 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3396 /*
3397 * We keep the session list lock across _all_ commands
3398 * for now, because the per-session lock does not
3399 * handle teardown properly.
3400 */
3401 session_lock_list();
3402 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3403 if (cmd_ctx->session == NULL) {
3404 if (cmd_ctx->lsm->session.name != NULL) {
3405 ret = LTTCOMM_SESS_NOT_FOUND;
3406 } else {
3407 /* If no session name specified */
3408 ret = LTTCOMM_SELECT_SESS;
3409 }
3410 goto error;
3411 } else {
3412 /* Acquire lock for the session */
3413 session_lock(cmd_ctx->session);
3414 }
3415 break;
3416 }
3417
3418 if (!need_domain) {
3419 goto skip_domain;
3420 }
3421 /*
3422 * Check domain type for specific "pre-action".
3423 */
3424 switch (cmd_ctx->lsm->domain.type) {
3425 case LTTNG_DOMAIN_KERNEL:
3426 if (!is_root) {
3427 ret = LTTCOMM_NEED_ROOT_SESSIOND;
3428 goto error;
3429 }
3430
3431 /* Kernel tracer check */
3432 if (kernel_tracer_fd == -1) {
3433 /* Basically, load kernel tracer modules */
3434 ret = init_kernel_tracer();
3435 if (ret != 0) {
3436 goto error;
3437 }
3438 }
3439
3440 /* Consumer is in an ERROR state. Report back to client */
3441 if (uatomic_read(&kernel_consumerd_state) == CONSUMER_ERROR) {
3442 ret = LTTCOMM_NO_KERNCONSUMERD;
3443 goto error;
3444 }
3445
3446 /* Need a session for kernel command */
3447 if (need_tracing_session) {
3448 if (cmd_ctx->session->kernel_session == NULL) {
3449 ret = create_kernel_session(cmd_ctx->session);
3450 if (ret < 0) {
3451 ret = LTTCOMM_KERN_SESS_FAIL;
3452 goto error;
3453 }
3454 }
3455
3456 /* Start the kernel consumer daemon */
3457 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3458 if (kconsumer_data.pid == 0 &&
3459 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3460 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3461 ret = start_consumerd(&kconsumer_data);
3462 if (ret < 0) {
3463 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3464 goto error;
3465 }
3466 uatomic_set(&kernel_consumerd_state, CONSUMER_STARTED);
3467 } else {
3468 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3469 }
3470 }
3471
3472 break;
3473 case LTTNG_DOMAIN_UST:
3474 {
3475 /* Consumer is in an ERROR state. Report back to client */
3476 if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
3477 ret = LTTCOMM_NO_USTCONSUMERD;
3478 goto error;
3479 }
3480
3481 if (need_tracing_session) {
3482 if (cmd_ctx->session->ust_session == NULL) {
3483 ret = create_ust_session(cmd_ctx->session,
3484 &cmd_ctx->lsm->domain);
3485 if (ret != LTTCOMM_OK) {
3486 goto error;
3487 }
3488 }
3489 /* Start the UST consumer daemons */
3490 /* 64-bit */
3491 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3492 if (consumerd64_bin[0] != '\0' &&
3493 ustconsumer64_data.pid == 0 &&
3494 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3495 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3496 ret = start_consumerd(&ustconsumer64_data);
3497 if (ret < 0) {
3498 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3499 ust_consumerd64_fd = -EINVAL;
3500 goto error;
3501 }
3502
3503 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3504 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
3505 } else {
3506 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3507 }
3508 /* 32-bit */
3509 if (consumerd32_bin[0] != '\0' &&
3510 ustconsumer32_data.pid == 0 &&
3511 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3512 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3513 ret = start_consumerd(&ustconsumer32_data);
3514 if (ret < 0) {
3515 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3516 ust_consumerd32_fd = -EINVAL;
3517 goto error;
3518 }
3519
3520 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3521 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
3522 } else {
3523 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3524 }
3525 }
3526 break;
3527 }
3528 default:
3529 break;
3530 }
3531skip_domain:
3532
3533 /* Validate consumer daemon state when start/stop trace command */
3534 if (cmd_ctx->lsm->cmd_type == LTTNG_START_TRACE ||
3535 cmd_ctx->lsm->cmd_type == LTTNG_STOP_TRACE) {
3536 switch (cmd_ctx->lsm->domain.type) {
3537 case LTTNG_DOMAIN_UST:
3538 if (uatomic_read(&ust_consumerd_state) != CONSUMER_STARTED) {
3539 ret = LTTCOMM_NO_USTCONSUMERD;
3540 goto error;
3541 }
3542 break;
3543 case LTTNG_DOMAIN_KERNEL:
3544 if (uatomic_read(&kernel_consumerd_state) != CONSUMER_STARTED) {
3545 ret = LTTCOMM_NO_KERNCONSUMERD;
3546 goto error;
3547 }
3548 break;
3549 }
3550 }
3551
3552 /*
3553 * Check that the UID or GID match that of the tracing session.
3554 * The root user can interact with all sessions.
3555 */
3556 if (need_tracing_session) {
3557 if (!session_access_ok(cmd_ctx->session,
3558 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
3559 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds))) {
3560 ret = LTTCOMM_EPERM;
3561 goto error;
3562 }
3563 }
3564
3565 /* Process by command type */
3566 switch (cmd_ctx->lsm->cmd_type) {
3567 case LTTNG_ADD_CONTEXT:
3568 {
3569 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3570 cmd_ctx->lsm->u.context.channel_name,
3571 cmd_ctx->lsm->u.context.event_name,
3572 &cmd_ctx->lsm->u.context.ctx);
3573 break;
3574 }
3575 case LTTNG_DISABLE_CHANNEL:
3576 {
3577 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3578 cmd_ctx->lsm->u.disable.channel_name);
3579 break;
3580 }
3581 case LTTNG_DISABLE_EVENT:
3582 {
3583 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3584 cmd_ctx->lsm->u.disable.channel_name,
3585 cmd_ctx->lsm->u.disable.name);
3586 break;
3587 }
3588 case LTTNG_DISABLE_ALL_EVENT:
3589 {
3590 DBG("Disabling all events");
3591
3592 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3593 cmd_ctx->lsm->u.disable.channel_name);
3594 break;
3595 }
3596 case LTTNG_ENABLE_CHANNEL:
3597 {
3598 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3599 &cmd_ctx->lsm->u.channel.chan);
3600 break;
3601 }
3602 case LTTNG_ENABLE_EVENT:
3603 {
3604 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3605 cmd_ctx->lsm->u.enable.channel_name,
3606 &cmd_ctx->lsm->u.enable.event);
3607 break;
3608 }
3609 case LTTNG_ENABLE_ALL_EVENT:
3610 {
3611 DBG("Enabling all events");
3612
3613 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3614 cmd_ctx->lsm->u.enable.channel_name,
3615 cmd_ctx->lsm->u.enable.event.type);
3616 break;
3617 }
3618 case LTTNG_LIST_TRACEPOINTS:
3619 {
3620 struct lttng_event *events;
3621 ssize_t nb_events;
3622
3623 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3624 if (nb_events < 0) {
3625 ret = -nb_events;
3626 goto error;
3627 }
3628
3629 /*
3630 * Setup lttng message with payload size set to the event list size in
3631 * bytes and then copy list into the llm payload.
3632 */
3633 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3634 if (ret < 0) {
3635 free(events);
3636 goto setup_error;
3637 }
3638
3639 /* Copy event list into message payload */
3640 memcpy(cmd_ctx->llm->payload, events,
3641 sizeof(struct lttng_event) * nb_events);
3642
3643 free(events);
3644
3645 ret = LTTCOMM_OK;
3646 break;
3647 }
3648 case LTTNG_LIST_TRACEPOINT_FIELDS:
3649 {
3650 struct lttng_event_field *fields;
3651 ssize_t nb_fields;
3652
3653 nb_fields = cmd_list_tracepoint_fields(cmd_ctx->lsm->domain.type, &fields);
3654 if (nb_fields < 0) {
3655 ret = -nb_fields;
3656 goto error;
3657 }
3658
3659 /*
3660 * Setup lttng message with payload size set to the event list size in
3661 * bytes and then copy list into the llm payload.
3662 */
3663 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event_field) * nb_fields);
3664 if (ret < 0) {
3665 free(fields);
3666 goto setup_error;
3667 }
3668
3669 /* Copy event list into message payload */
3670 memcpy(cmd_ctx->llm->payload, fields,
3671 sizeof(struct lttng_event_field) * nb_fields);
3672
3673 free(fields);
3674
3675 ret = LTTCOMM_OK;
3676 break;
3677 }
3678
3679 case LTTNG_START_TRACE:
3680 {
3681 ret = cmd_start_trace(cmd_ctx->session);
3682 break;
3683 }
3684 case LTTNG_STOP_TRACE:
3685 {
3686 ret = cmd_stop_trace(cmd_ctx->session);
3687 break;
3688 }
3689 case LTTNG_CREATE_SESSION:
3690 {
3691 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3692 cmd_ctx->lsm->session.path, &cmd_ctx->creds);
3693 break;
3694 }
3695 case LTTNG_DESTROY_SESSION:
3696 {
3697 ret = cmd_destroy_session(cmd_ctx->session,
3698 cmd_ctx->lsm->session.name);
3699 /*
3700 * Set session to NULL so we do not unlock it after
3701 * free.
3702 */
3703 cmd_ctx->session = NULL;
3704 break;
3705 }
3706 case LTTNG_LIST_DOMAINS:
3707 {
3708 ssize_t nb_dom;
3709 struct lttng_domain *domains;
3710
3711 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3712 if (nb_dom < 0) {
3713 ret = -nb_dom;
3714 goto error;
3715 }
3716
3717 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3718 if (ret < 0) {
3719 goto setup_error;
3720 }
3721
3722 /* Copy event list into message payload */
3723 memcpy(cmd_ctx->llm->payload, domains,
3724 nb_dom * sizeof(struct lttng_domain));
3725
3726 free(domains);
3727
3728 ret = LTTCOMM_OK;
3729 break;
3730 }
3731 case LTTNG_LIST_CHANNELS:
3732 {
3733 int nb_chan;
3734 struct lttng_channel *channels;
3735
3736 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
3737 cmd_ctx->session, &channels);
3738 if (nb_chan < 0) {
3739 ret = -nb_chan;
3740 goto error;
3741 }
3742
3743 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3744 if (ret < 0) {
3745 goto setup_error;
3746 }
3747
3748 /* Copy event list into message payload */
3749 memcpy(cmd_ctx->llm->payload, channels,
3750 nb_chan * sizeof(struct lttng_channel));
3751
3752 free(channels);
3753
3754 ret = LTTCOMM_OK;
3755 break;
3756 }
3757 case LTTNG_LIST_EVENTS:
3758 {
3759 ssize_t nb_event;
3760 struct lttng_event *events = NULL;
3761
3762 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
3763 cmd_ctx->lsm->u.list.channel_name, &events);
3764 if (nb_event < 0) {
3765 ret = -nb_event;
3766 goto error;
3767 }
3768
3769 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3770 if (ret < 0) {
3771 goto setup_error;
3772 }
3773
3774 /* Copy event list into message payload */
3775 memcpy(cmd_ctx->llm->payload, events,
3776 nb_event * sizeof(struct lttng_event));
3777
3778 free(events);
3779
3780 ret = LTTCOMM_OK;
3781 break;
3782 }
3783 case LTTNG_LIST_SESSIONS:
3784 {
3785 unsigned int nr_sessions;
3786
3787 session_lock_list();
3788 nr_sessions = lttng_sessions_count(
3789 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
3790 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
3791
3792 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * nr_sessions);
3793 if (ret < 0) {
3794 session_unlock_list();
3795 goto setup_error;
3796 }
3797
3798 /* Filled the session array */
3799 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload),
3800 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
3801 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
3802
3803 session_unlock_list();
3804
3805 ret = LTTCOMM_OK;
3806 break;
3807 }
3808 case LTTNG_CALIBRATE:
3809 {
3810 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3811 &cmd_ctx->lsm->u.calibrate);
3812 break;
3813 }
3814 case LTTNG_REGISTER_CONSUMER:
3815 {
3816 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3817 cmd_ctx->lsm->u.reg.path);
3818 break;
3819 }
3820 default:
3821 ret = LTTCOMM_UND;
3822 break;
3823 }
3824
3825error:
3826 if (cmd_ctx->llm == NULL) {
3827 DBG("Missing llm structure. Allocating one.");
3828 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3829 goto setup_error;
3830 }
3831 }
3832 /* Set return code */
3833 cmd_ctx->llm->ret_code = ret;
3834setup_error:
3835 if (cmd_ctx->session) {
3836 session_unlock(cmd_ctx->session);
3837 }
3838 if (need_tracing_session) {
3839 session_unlock_list();
3840 }
3841init_setup_error:
3842 return ret;
3843}
3844
3845/*
3846 * This thread manage all clients request using the unix client socket for
3847 * communication.
3848 */
3849static void *thread_manage_clients(void *data)
3850{
3851 int sock = -1, ret, i, pollfd;
3852 uint32_t revents, nb_fd;
3853 struct command_ctx *cmd_ctx = NULL;
3854 struct lttng_poll_event events;
3855
3856 DBG("[thread] Manage client started");
3857
3858 rcu_register_thread();
3859
3860 ret = lttcomm_listen_unix_sock(client_sock);
3861 if (ret < 0) {
3862 goto error;
3863 }
3864
3865 /*
3866 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3867 * more will be added to this poll set.
3868 */
3869 ret = create_thread_poll_set(&events, 2);
3870 if (ret < 0) {
3871 goto error;
3872 }
3873
3874 /* Add the application registration socket */
3875 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3876 if (ret < 0) {
3877 goto error;
3878 }
3879
3880 /*
3881 * Notify parent pid that we are ready to accept command for client side.
3882 */
3883 if (opt_sig_parent) {
3884 kill(ppid, SIGUSR1);
3885 }
3886
3887 while (1) {
3888 DBG("Accepting client command ...");
3889
3890 nb_fd = LTTNG_POLL_GETNB(&events);
3891
3892 /* Inifinite blocking call, waiting for transmission */
3893 restart:
3894 ret = lttng_poll_wait(&events, -1);
3895 if (ret < 0) {
3896 /*
3897 * Restart interrupted system call.
3898 */
3899 if (errno == EINTR) {
3900 goto restart;
3901 }
3902 goto error;
3903 }
3904
3905 for (i = 0; i < nb_fd; i++) {
3906 /* Fetch once the poll data */
3907 revents = LTTNG_POLL_GETEV(&events, i);
3908 pollfd = LTTNG_POLL_GETFD(&events, i);
3909
3910 /* Thread quit pipe has been closed. Killing thread. */
3911 ret = check_thread_quit_pipe(pollfd, revents);
3912 if (ret) {
3913 goto error;
3914 }
3915
3916 /* Event on the registration socket */
3917 if (pollfd == client_sock) {
3918 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3919 ERR("Client socket poll error");
3920 goto error;
3921 }
3922 }
3923 }
3924
3925 DBG("Wait for client response");
3926
3927 sock = lttcomm_accept_unix_sock(client_sock);
3928 if (sock < 0) {
3929 goto error;
3930 }
3931
3932 /* Set socket option for credentials retrieval */
3933 ret = lttcomm_setsockopt_creds_unix_sock(sock);
3934 if (ret < 0) {
3935 goto error;
3936 }
3937
3938 /* Allocate context command to process the client request */
3939 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3940 if (cmd_ctx == NULL) {
3941 PERROR("zmalloc cmd_ctx");
3942 goto error;
3943 }
3944
3945 /* Allocate data buffer for reception */
3946 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3947 if (cmd_ctx->lsm == NULL) {
3948 PERROR("zmalloc cmd_ctx->lsm");
3949 goto error;
3950 }
3951
3952 cmd_ctx->llm = NULL;
3953 cmd_ctx->session = NULL;
3954
3955 /*
3956 * Data is received from the lttng client. The struct
3957 * lttcomm_session_msg (lsm) contains the command and data request of
3958 * the client.
3959 */
3960 DBG("Receiving data from client ...");
3961 ret = lttcomm_recv_creds_unix_sock(sock, cmd_ctx->lsm,
3962 sizeof(struct lttcomm_session_msg), &cmd_ctx->creds);
3963 if (ret <= 0) {
3964 DBG("Nothing recv() from client... continuing");
3965 ret = close(sock);
3966 if (ret) {
3967 PERROR("close");
3968 }
3969 sock = -1;
3970 clean_command_ctx(&cmd_ctx);
3971 continue;
3972 }
3973
3974 // TODO: Validate cmd_ctx including sanity check for
3975 // security purpose.
3976
3977 rcu_thread_online();
3978 /*
3979 * This function dispatch the work to the kernel or userspace tracer
3980 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3981 * informations for the client. The command context struct contains
3982 * everything this function may needs.
3983 */
3984 ret = process_client_msg(cmd_ctx);
3985 rcu_thread_offline();
3986 if (ret < 0) {
3987 /*
3988 * TODO: Inform client somehow of the fatal error. At
3989 * this point, ret < 0 means that a zmalloc failed
3990 * (ENOMEM). Error detected but still accept command.
3991 */
3992 clean_command_ctx(&cmd_ctx);
3993 continue;
3994 }
3995
3996 DBG("Sending response (size: %d, retcode: %s)",
3997 cmd_ctx->lttng_msg_size,
3998 lttng_strerror(-cmd_ctx->llm->ret_code));
3999 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
4000 if (ret < 0) {
4001 ERR("Failed to send data back to client");
4002 }
4003
4004 /* End of transmission */
4005 ret = close(sock);
4006 if (ret) {
4007 PERROR("close");
4008 }
4009 sock = -1;
4010
4011 clean_command_ctx(&cmd_ctx);
4012 }
4013
4014error:
4015 DBG("Client thread dying");
4016 unlink(client_unix_sock_path);
4017 if (client_sock >= 0) {
4018 ret = close(client_sock);
4019 if (ret) {
4020 PERROR("close");
4021 }
4022 }
4023 if (sock >= 0) {
4024 ret = close(sock);
4025 if (ret) {
4026 PERROR("close");
4027 }
4028 }
4029
4030 lttng_poll_clean(&events);
4031 clean_command_ctx(&cmd_ctx);
4032
4033 rcu_unregister_thread();
4034 return NULL;
4035}
4036
4037
4038/*
4039 * usage function on stderr
4040 */
4041static void usage(void)
4042{
4043 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
4044 fprintf(stderr, " -h, --help Display this usage.\n");
4045 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
4046 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
4047 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
4048 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
4049 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
4050 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
4051 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
4052 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
4053 fprintf(stderr, " --consumerd32-path PATH Specify path for the 32-bit UST consumer daemon binary\n");
4054 fprintf(stderr, " --consumerd32-libdir PATH Specify path for the 32-bit UST consumer daemon libraries\n");
4055 fprintf(stderr, " --consumerd64-path PATH Specify path for the 64-bit UST consumer daemon binary\n");
4056 fprintf(stderr, " --consumerd64-libdir PATH Specify path for the 64-bit UST consumer daemon libraries\n");
4057 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
4058 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
4059 fprintf(stderr, " -V, --version Show version number.\n");
4060 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
4061 fprintf(stderr, " -q, --quiet No output at all.\n");
4062 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
4063 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
4064 fprintf(stderr, " --no-kernel Disable kernel tracer\n");
4065}
4066
4067/*
4068 * daemon argument parsing
4069 */
4070static int parse_args(int argc, char **argv)
4071{
4072 int c;
4073
4074 static struct option long_options[] = {
4075 { "client-sock", 1, 0, 'c' },
4076 { "apps-sock", 1, 0, 'a' },
4077 { "kconsumerd-cmd-sock", 1, 0, 'C' },
4078 { "kconsumerd-err-sock", 1, 0, 'E' },
4079 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
4080 { "ustconsumerd32-err-sock", 1, 0, 'H' },
4081 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
4082 { "ustconsumerd64-err-sock", 1, 0, 'F' },
4083 { "consumerd32-path", 1, 0, 'u' },
4084 { "consumerd32-libdir", 1, 0, 'U' },
4085 { "consumerd64-path", 1, 0, 't' },
4086 { "consumerd64-libdir", 1, 0, 'T' },
4087 { "daemonize", 0, 0, 'd' },
4088 { "sig-parent", 0, 0, 'S' },
4089 { "help", 0, 0, 'h' },
4090 { "group", 1, 0, 'g' },
4091 { "version", 0, 0, 'V' },
4092 { "quiet", 0, 0, 'q' },
4093 { "verbose", 0, 0, 'v' },
4094 { "verbose-consumer", 0, 0, 'Z' },
4095 { "no-kernel", 0, 0, 'N' },
4096 { NULL, 0, 0, 0 }
4097 };
4098
4099 while (1) {
4100 int option_index = 0;
4101 c = getopt_long(argc, argv, "dhqvVSN" "a:c:g:s:C:E:D:F:Z:u:t",
4102 long_options, &option_index);
4103 if (c == -1) {
4104 break;
4105 }
4106
4107 switch (c) {
4108 case 0:
4109 fprintf(stderr, "option %s", long_options[option_index].name);
4110 if (optarg) {
4111 fprintf(stderr, " with arg %s\n", optarg);
4112 }
4113 break;
4114 case 'c':
4115 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
4116 break;
4117 case 'a':
4118 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
4119 break;
4120 case 'd':
4121 opt_daemon = 1;
4122 break;
4123 case 'g':
4124 opt_tracing_group = optarg;
4125 break;
4126 case 'h':
4127 usage();
4128 exit(EXIT_FAILURE);
4129 case 'V':
4130 fprintf(stdout, "%s\n", VERSION);
4131 exit(EXIT_SUCCESS);
4132 case 'S':
4133 opt_sig_parent = 1;
4134 break;
4135 case 'E':
4136 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
4137 break;
4138 case 'C':
4139 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
4140 break;
4141 case 'F':
4142 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
4143 break;
4144 case 'D':
4145 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
4146 break;
4147 case 'H':
4148 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
4149 break;
4150 case 'G':
4151 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
4152 break;
4153 case 'N':
4154 opt_no_kernel = 1;
4155 break;
4156 case 'q':
4157 lttng_opt_quiet = 1;
4158 break;
4159 case 'v':
4160 /* Verbose level can increase using multiple -v */
4161 lttng_opt_verbose += 1;
4162 break;
4163 case 'Z':
4164 opt_verbose_consumer += 1;
4165 break;
4166 case 'u':
4167 consumerd32_bin= optarg;
4168 break;
4169 case 'U':
4170 consumerd32_libdir = optarg;
4171 break;
4172 case 't':
4173 consumerd64_bin = optarg;
4174 break;
4175 case 'T':
4176 consumerd64_libdir = optarg;
4177 break;
4178 default:
4179 /* Unknown option or other error.
4180 * Error is printed by getopt, just return */
4181 return -1;
4182 }
4183 }
4184
4185 return 0;
4186}
4187
4188/*
4189 * Creates the two needed socket by the daemon.
4190 * apps_sock - The communication socket for all UST apps.
4191 * client_sock - The communication of the cli tool (lttng).
4192 */
4193static int init_daemon_socket(void)
4194{
4195 int ret = 0;
4196 mode_t old_umask;
4197
4198 old_umask = umask(0);
4199
4200 /* Create client tool unix socket */
4201 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
4202 if (client_sock < 0) {
4203 ERR("Create unix sock failed: %s", client_unix_sock_path);
4204 ret = -1;
4205 goto end;
4206 }
4207
4208 /* File permission MUST be 660 */
4209 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
4210 if (ret < 0) {
4211 ERR("Set file permissions failed: %s", client_unix_sock_path);
4212 PERROR("chmod");
4213 goto end;
4214 }
4215
4216 /* Create the application unix socket */
4217 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
4218 if (apps_sock < 0) {
4219 ERR("Create unix sock failed: %s", apps_unix_sock_path);
4220 ret = -1;
4221 goto end;
4222 }
4223
4224 /* File permission MUST be 666 */
4225 ret = chmod(apps_unix_sock_path,
4226 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
4227 if (ret < 0) {
4228 ERR("Set file permissions failed: %s", apps_unix_sock_path);
4229 PERROR("chmod");
4230 goto end;
4231 }
4232
4233end:
4234 umask(old_umask);
4235 return ret;
4236}
4237
4238/*
4239 * Check if the global socket is available, and if a daemon is answering at the
4240 * other side. If yes, error is returned.
4241 */
4242static int check_existing_daemon(void)
4243{
4244 /* Is there anybody out there ? */
4245 if (lttng_session_daemon_alive()) {
4246 return -EEXIST;
4247 }
4248
4249 return 0;
4250}
4251
4252/*
4253 * Set the tracing group gid onto the client socket.
4254 *
4255 * Race window between mkdir and chown is OK because we are going from more
4256 * permissive (root.root) to less permissive (root.tracing).
4257 */
4258static int set_permissions(char *rundir)
4259{
4260 int ret;
4261 gid_t gid;
4262
4263 ret = allowed_group();
4264 if (ret < 0) {
4265 WARN("No tracing group detected");
4266 ret = 0;
4267 goto end;
4268 }
4269
4270 gid = ret;
4271
4272 /* Set lttng run dir */
4273 ret = chown(rundir, 0, gid);
4274 if (ret < 0) {
4275 ERR("Unable to set group on %s", rundir);
4276 PERROR("chown");
4277 }
4278
4279 /* Ensure tracing group can search the run dir */
4280 ret = chmod(rundir, S_IRWXU | S_IXGRP | S_IXOTH);
4281 if (ret < 0) {
4282 ERR("Unable to set permissions on %s", rundir);
4283 PERROR("chmod");
4284 }
4285
4286 /* lttng client socket path */
4287 ret = chown(client_unix_sock_path, 0, gid);
4288 if (ret < 0) {
4289 ERR("Unable to set group on %s", client_unix_sock_path);
4290 PERROR("chown");
4291 }
4292
4293 /* kconsumer error socket path */
4294 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
4295 if (ret < 0) {
4296 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
4297 PERROR("chown");
4298 }
4299
4300 /* 64-bit ustconsumer error socket path */
4301 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
4302 if (ret < 0) {
4303 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
4304 PERROR("chown");
4305 }
4306
4307 /* 32-bit ustconsumer compat32 error socket path */
4308 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
4309 if (ret < 0) {
4310 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
4311 PERROR("chown");
4312 }
4313
4314 DBG("All permissions are set");
4315
4316end:
4317 return ret;
4318}
4319
4320/*
4321 * Create the pipe used to wake up the kernel thread.
4322 * Closed in cleanup().
4323 */
4324static int create_kernel_poll_pipe(void)
4325{
4326 int ret, i;
4327
4328 ret = pipe(kernel_poll_pipe);
4329 if (ret < 0) {
4330 PERROR("kernel poll pipe");
4331 goto error;
4332 }
4333
4334 for (i = 0; i < 2; i++) {
4335 ret = fcntl(kernel_poll_pipe[i], F_SETFD, FD_CLOEXEC);
4336 if (ret < 0) {
4337 PERROR("fcntl kernel_poll_pipe");
4338 goto error;
4339 }
4340 }
4341
4342error:
4343 return ret;
4344}
4345
4346/*
4347 * Create the application command pipe to wake thread_manage_apps.
4348 * Closed in cleanup().
4349 */
4350static int create_apps_cmd_pipe(void)
4351{
4352 int ret, i;
4353
4354 ret = pipe(apps_cmd_pipe);
4355 if (ret < 0) {
4356 PERROR("apps cmd pipe");
4357 goto error;
4358 }
4359
4360 for (i = 0; i < 2; i++) {
4361 ret = fcntl(apps_cmd_pipe[i], F_SETFD, FD_CLOEXEC);
4362 if (ret < 0) {
4363 PERROR("fcntl apps_cmd_pipe");
4364 goto error;
4365 }
4366 }
4367
4368error:
4369 return ret;
4370}
4371
4372/*
4373 * Create the lttng run directory needed for all global sockets and pipe.
4374 */
4375static int create_lttng_rundir(const char *rundir)
4376{
4377 int ret;
4378
4379 DBG3("Creating LTTng run directory: %s", rundir);
4380
4381 ret = mkdir(rundir, S_IRWXU);
4382 if (ret < 0) {
4383 if (errno != EEXIST) {
4384 ERR("Unable to create %s", rundir);
4385 goto error;
4386 } else {
4387 ret = 0;
4388 }
4389 }
4390
4391error:
4392 return ret;
4393}
4394
4395/*
4396 * Setup sockets and directory needed by the kconsumerd communication with the
4397 * session daemon.
4398 */
4399static int set_consumer_sockets(struct consumer_data *consumer_data,
4400 const char *rundir)
4401{
4402 int ret;
4403 char path[PATH_MAX];
4404
4405 switch (consumer_data->type) {
4406 case LTTNG_CONSUMER_KERNEL:
4407 snprintf(path, PATH_MAX, DEFAULT_KCONSUMERD_PATH, rundir);
4408 break;
4409 case LTTNG_CONSUMER64_UST:
4410 snprintf(path, PATH_MAX, DEFAULT_USTCONSUMERD64_PATH, rundir);
4411 break;
4412 case LTTNG_CONSUMER32_UST:
4413 snprintf(path, PATH_MAX, DEFAULT_USTCONSUMERD32_PATH, rundir);
4414 break;
4415 default:
4416 ERR("Consumer type unknown");
4417 ret = -EINVAL;
4418 goto error;
4419 }
4420
4421 DBG2("Creating consumer directory: %s", path);
4422
4423 ret = mkdir(path, S_IRWXU);
4424 if (ret < 0) {
4425 if (errno != EEXIST) {
4426 PERROR("mkdir");
4427 ERR("Failed to create %s", path);
4428 goto error;
4429 }
4430 ret = -1;
4431 }
4432
4433 /* Create the kconsumerd error unix socket */
4434 consumer_data->err_sock =
4435 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
4436 if (consumer_data->err_sock < 0) {
4437 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
4438 ret = -1;
4439 goto error;
4440 }
4441
4442 /* File permission MUST be 660 */
4443 ret = chmod(consumer_data->err_unix_sock_path,
4444 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
4445 if (ret < 0) {
4446 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
4447 PERROR("chmod");
4448 goto error;
4449 }
4450
4451error:
4452 return ret;
4453}
4454
4455/*
4456 * Signal handler for the daemon
4457 *
4458 * Simply stop all worker threads, leaving main() return gracefully after
4459 * joining all threads and calling cleanup().
4460 */
4461static void sighandler(int sig)
4462{
4463 switch (sig) {
4464 case SIGPIPE:
4465 DBG("SIGPIPE caught");
4466 return;
4467 case SIGINT:
4468 DBG("SIGINT caught");
4469 stop_threads();
4470 break;
4471 case SIGTERM:
4472 DBG("SIGTERM caught");
4473 stop_threads();
4474 break;
4475 default:
4476 break;
4477 }
4478}
4479
4480/*
4481 * Setup signal handler for :
4482 * SIGINT, SIGTERM, SIGPIPE
4483 */
4484static int set_signal_handler(void)
4485{
4486 int ret = 0;
4487 struct sigaction sa;
4488 sigset_t sigset;
4489
4490 if ((ret = sigemptyset(&sigset)) < 0) {
4491 PERROR("sigemptyset");
4492 return ret;
4493 }
4494
4495 sa.sa_handler = sighandler;
4496 sa.sa_mask = sigset;
4497 sa.sa_flags = 0;
4498 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
4499 PERROR("sigaction");
4500 return ret;
4501 }
4502
4503 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
4504 PERROR("sigaction");
4505 return ret;
4506 }
4507
4508 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
4509 PERROR("sigaction");
4510 return ret;
4511 }
4512
4513 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
4514
4515 return ret;
4516}
4517
4518/*
4519 * Set open files limit to unlimited. This daemon can open a large number of
4520 * file descriptors in order to consumer multiple kernel traces.
4521 */
4522static void set_ulimit(void)
4523{
4524 int ret;
4525 struct rlimit lim;
4526
4527 /* The kernel does not allowed an infinite limit for open files */
4528 lim.rlim_cur = 65535;
4529 lim.rlim_max = 65535;
4530
4531 ret = setrlimit(RLIMIT_NOFILE, &lim);
4532 if (ret < 0) {
4533 PERROR("failed to set open files limit");
4534 }
4535}
4536
4537/*
4538 * main
4539 */
4540int main(int argc, char **argv)
4541{
4542 int ret = 0;
4543 void *status;
4544 const char *home_path;
4545
4546 init_kernel_workarounds();
4547
4548 rcu_register_thread();
4549
4550 /* Create thread quit pipe */
4551 if ((ret = init_thread_quit_pipe()) < 0) {
4552 goto error;
4553 }
4554
4555 setup_consumerd_path();
4556
4557 /* Parse arguments */
4558 progname = argv[0];
4559 if ((ret = parse_args(argc, argv) < 0)) {
4560 goto error;
4561 }
4562
4563 /* Daemonize */
4564 if (opt_daemon) {
4565 ret = daemon(0, 0);
4566 if (ret < 0) {
4567 PERROR("daemon");
4568 goto error;
4569 }
4570 }
4571
4572 /* Check if daemon is UID = 0 */
4573 is_root = !getuid();
4574
4575 if (is_root) {
4576 rundir = strdup(DEFAULT_LTTNG_RUNDIR);
4577
4578 /* Create global run dir with root access */
4579 ret = create_lttng_rundir(rundir);
4580 if (ret < 0) {
4581 goto error;
4582 }
4583
4584 if (strlen(apps_unix_sock_path) == 0) {
4585 snprintf(apps_unix_sock_path, PATH_MAX,
4586 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
4587 }
4588
4589 if (strlen(client_unix_sock_path) == 0) {
4590 snprintf(client_unix_sock_path, PATH_MAX,
4591 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
4592 }
4593
4594 /* Set global SHM for ust */
4595 if (strlen(wait_shm_path) == 0) {
4596 snprintf(wait_shm_path, PATH_MAX,
4597 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
4598 }
4599
4600 /* Setup kernel consumerd path */
4601 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX,
4602 DEFAULT_KCONSUMERD_ERR_SOCK_PATH, rundir);
4603 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX,
4604 DEFAULT_KCONSUMERD_CMD_SOCK_PATH, rundir);
4605
4606 DBG2("Kernel consumer err path: %s",
4607 kconsumer_data.err_unix_sock_path);
4608 DBG2("Kernel consumer cmd path: %s",
4609 kconsumer_data.cmd_unix_sock_path);
4610 } else {
4611 home_path = get_home_dir();
4612 if (home_path == NULL) {
4613 /* TODO: Add --socket PATH option */
4614 ERR("Can't get HOME directory for sockets creation.");
4615 ret = -EPERM;
4616 goto error;
4617 }
4618
4619 /*
4620 * Create rundir from home path. This will create something like
4621 * $HOME/.lttng
4622 */
4623 ret = asprintf(&rundir, DEFAULT_LTTNG_HOME_RUNDIR, home_path);
4624 if (ret < 0) {
4625 ret = -ENOMEM;
4626 goto error;
4627 }
4628
4629 ret = create_lttng_rundir(rundir);
4630 if (ret < 0) {
4631 goto error;
4632 }
4633
4634 if (strlen(apps_unix_sock_path) == 0) {
4635 snprintf(apps_unix_sock_path, PATH_MAX,
4636 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
4637 }
4638
4639 /* Set the cli tool unix socket path */
4640 if (strlen(client_unix_sock_path) == 0) {
4641 snprintf(client_unix_sock_path, PATH_MAX,
4642 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
4643 }
4644
4645 /* Set global SHM for ust */
4646 if (strlen(wait_shm_path) == 0) {
4647 snprintf(wait_shm_path, PATH_MAX,
4648 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
4649 }
4650 }
4651
4652 /* Set consumer initial state */
4653 kernel_consumerd_state = CONSUMER_STOPPED;
4654 ust_consumerd_state = CONSUMER_STOPPED;
4655
4656 DBG("Client socket path %s", client_unix_sock_path);
4657 DBG("Application socket path %s", apps_unix_sock_path);
4658 DBG("LTTng run directory path: %s", rundir);
4659
4660 /* 32 bits consumerd path setup */
4661 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX,
4662 DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH, rundir);
4663 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX,
4664 DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH, rundir);
4665
4666 DBG2("UST consumer 32 bits err path: %s",
4667 ustconsumer32_data.err_unix_sock_path);
4668 DBG2("UST consumer 32 bits cmd path: %s",
4669 ustconsumer32_data.cmd_unix_sock_path);
4670
4671 /* 64 bits consumerd path setup */
4672 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX,
4673 DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH, rundir);
4674 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX,
4675 DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH, rundir);
4676
4677 DBG2("UST consumer 64 bits err path: %s",
4678 ustconsumer64_data.err_unix_sock_path);
4679 DBG2("UST consumer 64 bits cmd path: %s",
4680 ustconsumer64_data.cmd_unix_sock_path);
4681
4682 /*
4683 * See if daemon already exist.
4684 */
4685 if ((ret = check_existing_daemon()) < 0) {
4686 ERR("Already running daemon.\n");
4687 /*
4688 * We do not goto exit because we must not cleanup()
4689 * because a daemon is already running.
4690 */
4691 goto error;
4692 }
4693
4694 /*
4695 * Init UST app hash table. Alloc hash table before this point since
4696 * cleanup() can get called after that point.
4697 */
4698 ust_app_ht_alloc();
4699
4700 /* After this point, we can safely call cleanup() with "goto exit" */
4701
4702 /*
4703 * These actions must be executed as root. We do that *after* setting up
4704 * the sockets path because we MUST make the check for another daemon using
4705 * those paths *before* trying to set the kernel consumer sockets and init
4706 * kernel tracer.
4707 */
4708 if (is_root) {
4709 ret = set_consumer_sockets(&kconsumer_data, rundir);
4710 if (ret < 0) {
4711 goto exit;
4712 }
4713
4714 /* Setup kernel tracer */
4715 if (!opt_no_kernel) {
4716 init_kernel_tracer();
4717 }
4718
4719 /* Set ulimit for open files */
4720 set_ulimit();
4721 }
4722 /* init lttng_fd tracking must be done after set_ulimit. */
4723 lttng_fd_init();
4724
4725 ret = set_consumer_sockets(&ustconsumer64_data, rundir);
4726 if (ret < 0) {
4727 goto exit;
4728 }
4729
4730 ret = set_consumer_sockets(&ustconsumer32_data, rundir);
4731 if (ret < 0) {
4732 goto exit;
4733 }
4734
4735 if ((ret = set_signal_handler()) < 0) {
4736 goto exit;
4737 }
4738
4739 /* Setup the needed unix socket */
4740 if ((ret = init_daemon_socket()) < 0) {
4741 goto exit;
4742 }
4743
4744 /* Set credentials to socket */
4745 if (is_root && ((ret = set_permissions(rundir)) < 0)) {
4746 goto exit;
4747 }
4748
4749 /* Get parent pid if -S, --sig-parent is specified. */
4750 if (opt_sig_parent) {
4751 ppid = getppid();
4752 }
4753
4754 /* Setup the kernel pipe for waking up the kernel thread */
4755 if ((ret = create_kernel_poll_pipe()) < 0) {
4756 goto exit;
4757 }
4758
4759 /* Setup the thread apps communication pipe. */
4760 if ((ret = create_apps_cmd_pipe()) < 0) {
4761 goto exit;
4762 }
4763
4764 /* Init UST command queue. */
4765 cds_wfq_init(&ust_cmd_queue.queue);
4766
4767 /*
4768 * Get session list pointer. This pointer MUST NOT be free(). This list is
4769 * statically declared in session.c
4770 */
4771 session_list_ptr = session_get_list();
4772
4773 /* Set up max poll set size */
4774 lttng_poll_set_max_size();
4775
4776 /* Create thread to manage the client socket */
4777 ret = pthread_create(&client_thread, NULL,
4778 thread_manage_clients, (void *) NULL);
4779 if (ret != 0) {
4780 PERROR("pthread_create clients");
4781 goto exit_client;
4782 }
4783
4784 /* Create thread to dispatch registration */
4785 ret = pthread_create(&dispatch_thread, NULL,
4786 thread_dispatch_ust_registration, (void *) NULL);
4787 if (ret != 0) {
4788 PERROR("pthread_create dispatch");
4789 goto exit_dispatch;
4790 }
4791
4792 /* Create thread to manage application registration. */
4793 ret = pthread_create(&reg_apps_thread, NULL,
4794 thread_registration_apps, (void *) NULL);
4795 if (ret != 0) {
4796 PERROR("pthread_create registration");
4797 goto exit_reg_apps;
4798 }
4799
4800 /* Create thread to manage application socket */
4801 ret = pthread_create(&apps_thread, NULL,
4802 thread_manage_apps, (void *) NULL);
4803 if (ret != 0) {
4804 PERROR("pthread_create apps");
4805 goto exit_apps;
4806 }
4807
4808 /* Create kernel thread to manage kernel event */
4809 ret = pthread_create(&kernel_thread, NULL,
4810 thread_manage_kernel, (void *) NULL);
4811 if (ret != 0) {
4812 PERROR("pthread_create kernel");
4813 goto exit_kernel;
4814 }
4815
4816 ret = pthread_join(kernel_thread, &status);
4817 if (ret != 0) {
4818 PERROR("pthread_join");
4819 goto error; /* join error, exit without cleanup */
4820 }
4821
4822exit_kernel:
4823 ret = pthread_join(apps_thread, &status);
4824 if (ret != 0) {
4825 PERROR("pthread_join");
4826 goto error; /* join error, exit without cleanup */
4827 }
4828
4829exit_apps:
4830 ret = pthread_join(reg_apps_thread, &status);
4831 if (ret != 0) {
4832 PERROR("pthread_join");
4833 goto error; /* join error, exit without cleanup */
4834 }
4835
4836exit_reg_apps:
4837 ret = pthread_join(dispatch_thread, &status);
4838 if (ret != 0) {
4839 PERROR("pthread_join");
4840 goto error; /* join error, exit without cleanup */
4841 }
4842
4843exit_dispatch:
4844 ret = pthread_join(client_thread, &status);
4845 if (ret != 0) {
4846 PERROR("pthread_join");
4847 goto error; /* join error, exit without cleanup */
4848 }
4849
4850 ret = join_consumer_thread(&kconsumer_data);
4851 if (ret != 0) {
4852 PERROR("join_consumer");
4853 goto error; /* join error, exit without cleanup */
4854 }
4855
4856exit_client:
4857exit:
4858 /*
4859 * cleanup() is called when no other thread is running.
4860 */
4861 rcu_thread_online();
4862 cleanup();
4863 rcu_thread_offline();
4864 rcu_unregister_thread();
4865 if (!ret) {
4866 exit(EXIT_SUCCESS);
4867 }
4868error:
4869 exit(EXIT_FAILURE);
4870}
LTTng 2.0 tools and control repository
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