Keep track of FD used for UST applications (v2)
[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/futex.h>
37#include <unistd.h>
38#include <config.h>
39
40#include <common/common.h>
41#include <common/compat/poll.h>
42#include <common/compat/socket.h>
43#include <common/defaults.h>
44#include <common/kernel-consumer/kernel-consumer.h>
45#include <common/ust-consumer/ust-consumer.h>
46
47#include "lttng-sessiond.h"
48#include "channel.h"
49#include "context.h"
50#include "event.h"
51#include "futex.h"
52#include "kernel.h"
53#include "modprobe.h"
54#include "shm.h"
55#include "ust-ctl.h"
56#include "utils.h"
57#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
182static
183void setup_consumerd_path(void)
184{
185 const char *bin, *libdir;
186
187 /*
188 * Allow INSTALL_BIN_PATH to be used as a target path for the
189 * native architecture size consumer if CONFIG_CONSUMER*_PATH
190 * has not been defined.
191 */
192#if (CAA_BITS_PER_LONG == 32)
193 if (!consumerd32_bin[0]) {
194 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
195 }
196 if (!consumerd32_libdir[0]) {
197 consumerd32_libdir = INSTALL_LIB_PATH;
198 }
199#elif (CAA_BITS_PER_LONG == 64)
200 if (!consumerd64_bin[0]) {
201 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
202 }
203 if (!consumerd64_libdir[0]) {
204 consumerd64_libdir = INSTALL_LIB_PATH;
205 }
206#else
207#error "Unknown bitness"
208#endif
209
210 /*
211 * runtime env. var. overrides the build default.
212 */
213 bin = getenv("LTTNG_CONSUMERD32_BIN");
214 if (bin) {
215 consumerd32_bin = bin;
216 }
217 bin = getenv("LTTNG_CONSUMERD64_BIN");
218 if (bin) {
219 consumerd64_bin = bin;
220 }
221 libdir = getenv("LTTNG_CONSUMERD32_LIBDIR");
222 if (libdir) {
223 consumerd32_libdir = libdir;
224 }
225 libdir = getenv("LTTNG_CONSUMERD64_LIBDIR");
226 if (libdir) {
227 consumerd64_libdir = libdir;
228 }
229}
230
231/*
232 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
233 */
234static int create_thread_poll_set(struct lttng_poll_event *events,
235 unsigned int size)
236{
237 int ret;
238
239 if (events == NULL || size == 0) {
240 ret = -1;
241 goto error;
242 }
243
244 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
245 if (ret < 0) {
246 goto error;
247 }
248
249 /* Add quit pipe */
250 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
251 if (ret < 0) {
252 goto error;
253 }
254
255 return 0;
256
257error:
258 return ret;
259}
260
261/*
262 * Check if the thread quit pipe was triggered.
263 *
264 * Return 1 if it was triggered else 0;
265 */
266static int check_thread_quit_pipe(int fd, uint32_t events)
267{
268 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
269 return 1;
270 }
271
272 return 0;
273}
274
275/*
276 * Return group ID of the tracing group or -1 if not found.
277 */
278static gid_t allowed_group(void)
279{
280 struct group *grp;
281
282 if (opt_tracing_group) {
283 grp = getgrnam(opt_tracing_group);
284 } else {
285 grp = getgrnam(default_tracing_group);
286 }
287 if (!grp) {
288 return -1;
289 } else {
290 return grp->gr_gid;
291 }
292}
293
294/*
295 * Init thread quit pipe.
296 *
297 * Return -1 on error or 0 if all pipes are created.
298 */
299static int init_thread_quit_pipe(void)
300{
301 int ret, i;
302
303 ret = pipe(thread_quit_pipe);
304 if (ret < 0) {
305 PERROR("thread quit pipe");
306 goto error;
307 }
308
309 for (i = 0; i < 2; i++) {
310 ret = fcntl(thread_quit_pipe[i], F_SETFD, FD_CLOEXEC);
311 if (ret < 0) {
312 PERROR("fcntl");
313 goto error;
314 }
315 }
316
317error:
318 return ret;
319}
320
321/*
322 * Complete teardown of a kernel session. This free all data structure related
323 * to a kernel session and update counter.
324 */
325static void teardown_kernel_session(struct ltt_session *session)
326{
327 if (!session->kernel_session) {
328 DBG3("No kernel session when tearing down session");
329 return;
330 }
331
332 DBG("Tearing down kernel session");
333
334 /*
335 * If a custom kernel consumer was registered, close the socket before
336 * tearing down the complete kernel session structure
337 */
338 if (kconsumer_data.cmd_sock >= 0 &&
339 session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
340 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
341 }
342
343 trace_kernel_destroy_session(session->kernel_session);
344}
345
346/*
347 * Complete teardown of all UST sessions. This will free everything on his path
348 * and destroy the core essence of all ust sessions :)
349 */
350static void teardown_ust_session(struct ltt_session *session)
351{
352 int ret;
353
354 if (!session->ust_session) {
355 DBG3("No UST session when tearing down session");
356 return;
357 }
358
359 DBG("Tearing down UST session(s)");
360
361 ret = ust_app_destroy_trace_all(session->ust_session);
362 if (ret) {
363 ERR("Error in ust_app_destroy_trace_all");
364 }
365
366 trace_ust_destroy_session(session->ust_session);
367}
368
369/*
370 * Stop all threads by closing the thread quit pipe.
371 */
372static void stop_threads(void)
373{
374 int ret;
375
376 /* Stopping all threads */
377 DBG("Terminating all threads");
378 ret = notify_thread_pipe(thread_quit_pipe[1]);
379 if (ret < 0) {
380 ERR("write error on thread quit pipe");
381 }
382
383 /* Dispatch thread */
384 dispatch_thread_exit = 1;
385 futex_nto1_wake(&ust_cmd_queue.futex);
386}
387
388/*
389 * Cleanup the daemon
390 */
391static void cleanup(void)
392{
393 int ret, i;
394 char *cmd;
395 struct ltt_session *sess, *stmp;
396
397 DBG("Cleaning up");
398
399 DBG("Removing %s directory", rundir);
400 ret = asprintf(&cmd, "rm -rf %s", rundir);
401 if (ret < 0) {
402 ERR("asprintf failed. Something is really wrong!");
403 }
404
405 /* Remove lttng run directory */
406 ret = system(cmd);
407 if (ret < 0) {
408 ERR("Unable to clean %s", rundir);
409 }
410 free(cmd);
411
412 DBG("Cleaning up all sessions");
413
414 /* Destroy session list mutex */
415 if (session_list_ptr != NULL) {
416 pthread_mutex_destroy(&session_list_ptr->lock);
417
418 /* Cleanup ALL session */
419 cds_list_for_each_entry_safe(sess, stmp,
420 &session_list_ptr->head, list) {
421 teardown_kernel_session(sess);
422 teardown_ust_session(sess);
423 free(sess);
424 }
425 }
426
427 DBG("Closing all UST sockets");
428 ust_app_clean_list();
429
430 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
431
432 if (is_root && !opt_no_kernel) {
433 DBG2("Closing kernel fd");
434 if (kernel_tracer_fd >= 0) {
435 ret = close(kernel_tracer_fd);
436 if (ret) {
437 PERROR("close");
438 }
439 }
440 DBG("Unloading kernel modules");
441 modprobe_remove_lttng_all();
442 }
443
444 /*
445 * Closing all pipes used for communication between threads.
446 */
447 for (i = 0; i < 2; i++) {
448 if (kernel_poll_pipe[i] >= 0) {
449 ret = close(kernel_poll_pipe[i]);
450 if (ret) {
451 PERROR("close");
452 }
453
454 }
455 }
456 for (i = 0; i < 2; i++) {
457 if (thread_quit_pipe[i] >= 0) {
458 ret = close(thread_quit_pipe[i]);
459 if (ret) {
460 PERROR("close");
461 }
462 }
463 }
464 for (i = 0; i < 2; i++) {
465 if (apps_cmd_pipe[i] >= 0) {
466 ret = close(apps_cmd_pipe[i]);
467 if (ret) {
468 PERROR("close");
469 }
470 }
471 }
472
473 /* <fun> */
474 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
475 "Matthew, BEET driven development works!%c[%dm",
476 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
477 /* </fun> */
478}
479
480/*
481 * Send data on a unix socket using the liblttsessiondcomm API.
482 *
483 * Return lttcomm error code.
484 */
485static int send_unix_sock(int sock, void *buf, size_t len)
486{
487 /* Check valid length */
488 if (len <= 0) {
489 return -1;
490 }
491
492 return lttcomm_send_unix_sock(sock, buf, len);
493}
494
495/*
496 * Free memory of a command context structure.
497 */
498static void clean_command_ctx(struct command_ctx **cmd_ctx)
499{
500 DBG("Clean command context structure");
501 if (*cmd_ctx) {
502 if ((*cmd_ctx)->llm) {
503 free((*cmd_ctx)->llm);
504 }
505 if ((*cmd_ctx)->lsm) {
506 free((*cmd_ctx)->lsm);
507 }
508 free(*cmd_ctx);
509 *cmd_ctx = NULL;
510 }
511}
512
513/*
514 * Send all stream fds of kernel channel to the consumer.
515 */
516static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
517 int sock, struct ltt_kernel_channel *channel,
518 uid_t uid, gid_t gid)
519{
520 int ret;
521 struct ltt_kernel_stream *stream;
522 struct lttcomm_consumer_msg lkm;
523
524 DBG("Sending streams of channel %s to kernel consumer",
525 channel->channel->name);
526
527 /* Send channel */
528 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
529 lkm.u.channel.channel_key = channel->fd;
530 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
531 lkm.u.channel.mmap_len = 0; /* for kernel */
532 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
533 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
534 if (ret < 0) {
535 PERROR("send consumer channel");
536 goto error;
537 }
538
539 /* Send streams */
540 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
541 if (!stream->fd) {
542 continue;
543 }
544 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
545 lkm.u.stream.channel_key = channel->fd;
546 lkm.u.stream.stream_key = stream->fd;
547 lkm.u.stream.state = stream->state;
548 lkm.u.stream.output = channel->channel->attr.output;
549 lkm.u.stream.mmap_len = 0; /* for kernel */
550 lkm.u.stream.uid = uid;
551 lkm.u.stream.gid = gid;
552 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
553 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
554 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
555 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
556 if (ret < 0) {
557 PERROR("send consumer stream");
558 goto error;
559 }
560 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
561 if (ret < 0) {
562 PERROR("send consumer stream ancillary data");
563 goto error;
564 }
565 }
566
567 DBG("consumer channel streams sent");
568
569 return 0;
570
571error:
572 return ret;
573}
574
575/*
576 * Send all stream fds of the kernel session to the consumer.
577 */
578static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
579 struct ltt_kernel_session *session)
580{
581 int ret;
582 struct ltt_kernel_channel *chan;
583 struct lttcomm_consumer_msg lkm;
584 int sock = session->consumer_fd;
585
586 DBG("Sending metadata stream fd");
587
588 /* Extra protection. It's NOT supposed to be set to -1 at this point */
589 if (session->consumer_fd < 0) {
590 session->consumer_fd = consumer_data->cmd_sock;
591 }
592
593 if (session->metadata_stream_fd >= 0) {
594 /* Send metadata channel fd */
595 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
596 lkm.u.channel.channel_key = session->metadata->fd;
597 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
598 lkm.u.channel.mmap_len = 0; /* for kernel */
599 DBG("Sending metadata channel %d to consumer", lkm.u.channel.channel_key);
600 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
601 if (ret < 0) {
602 PERROR("send consumer channel");
603 goto error;
604 }
605
606 /* Send metadata stream fd */
607 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
608 lkm.u.stream.channel_key = session->metadata->fd;
609 lkm.u.stream.stream_key = session->metadata_stream_fd;
610 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
611 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
612 lkm.u.stream.mmap_len = 0; /* for kernel */
613 lkm.u.stream.uid = session->uid;
614 lkm.u.stream.gid = session->gid;
615 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
616 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
617 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
618 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
619 if (ret < 0) {
620 PERROR("send consumer stream");
621 goto error;
622 }
623 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
624 if (ret < 0) {
625 PERROR("send consumer stream");
626 goto error;
627 }
628 }
629
630 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
631 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
632 session->uid, session->gid);
633 if (ret < 0) {
634 goto error;
635 }
636 }
637
638 DBG("consumer fds (metadata and channel streams) sent");
639
640 return 0;
641
642error:
643 return ret;
644}
645
646/*
647 * Notify UST applications using the shm mmap futex.
648 */
649static int notify_ust_apps(int active)
650{
651 char *wait_shm_mmap;
652
653 DBG("Notifying applications of session daemon state: %d", active);
654
655 /* See shm.c for this call implying mmap, shm and futex calls */
656 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
657 if (wait_shm_mmap == NULL) {
658 goto error;
659 }
660
661 /* Wake waiting process */
662 futex_wait_update((int32_t *) wait_shm_mmap, active);
663
664 /* Apps notified successfully */
665 return 0;
666
667error:
668 return -1;
669}
670
671/*
672 * Setup the outgoing data buffer for the response (llm) by allocating the
673 * right amount of memory and copying the original information from the lsm
674 * structure.
675 *
676 * Return total size of the buffer pointed by buf.
677 */
678static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
679{
680 int ret, buf_size;
681
682 buf_size = size;
683
684 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
685 if (cmd_ctx->llm == NULL) {
686 PERROR("zmalloc");
687 ret = -ENOMEM;
688 goto error;
689 }
690
691 /* Copy common data */
692 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
693 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
694
695 cmd_ctx->llm->data_size = size;
696 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
697
698 return buf_size;
699
700error:
701 return ret;
702}
703
704/*
705 * Update the kernel poll set of all channel fd available over all tracing
706 * session. Add the wakeup pipe at the end of the set.
707 */
708static int update_kernel_poll(struct lttng_poll_event *events)
709{
710 int ret;
711 struct ltt_session *session;
712 struct ltt_kernel_channel *channel;
713
714 DBG("Updating kernel poll set");
715
716 session_lock_list();
717 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
718 session_lock(session);
719 if (session->kernel_session == NULL) {
720 session_unlock(session);
721 continue;
722 }
723
724 cds_list_for_each_entry(channel,
725 &session->kernel_session->channel_list.head, list) {
726 /* Add channel fd to the kernel poll set */
727 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
728 if (ret < 0) {
729 session_unlock(session);
730 goto error;
731 }
732 DBG("Channel fd %d added to kernel set", channel->fd);
733 }
734 session_unlock(session);
735 }
736 session_unlock_list();
737
738 return 0;
739
740error:
741 session_unlock_list();
742 return -1;
743}
744
745/*
746 * Find the channel fd from 'fd' over all tracing session. When found, check
747 * for new channel stream and send those stream fds to the kernel consumer.
748 *
749 * Useful for CPU hotplug feature.
750 */
751static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
752{
753 int ret = 0;
754 struct ltt_session *session;
755 struct ltt_kernel_channel *channel;
756
757 DBG("Updating kernel streams for channel fd %d", fd);
758
759 session_lock_list();
760 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
761 session_lock(session);
762 if (session->kernel_session == NULL) {
763 session_unlock(session);
764 continue;
765 }
766
767 /* This is not suppose to be -1 but this is an extra security check */
768 if (session->kernel_session->consumer_fd < 0) {
769 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
770 }
771
772 cds_list_for_each_entry(channel,
773 &session->kernel_session->channel_list.head, list) {
774 if (channel->fd == fd) {
775 DBG("Channel found, updating kernel streams");
776 ret = kernel_open_channel_stream(channel);
777 if (ret < 0) {
778 goto error;
779 }
780
781 /*
782 * Have we already sent fds to the consumer? If yes, it means
783 * that tracing is started so it is safe to send our updated
784 * stream fds.
785 */
786 if (session->kernel_session->consumer_fds_sent == 1) {
787 ret = send_kconsumer_channel_streams(consumer_data,
788 session->kernel_session->consumer_fd, channel,
789 session->uid, session->gid);
790 if (ret < 0) {
791 goto error;
792 }
793 }
794 goto error;
795 }
796 }
797 session_unlock(session);
798 }
799 session_unlock_list();
800 return ret;
801
802error:
803 session_unlock(session);
804 session_unlock_list();
805 return ret;
806}
807
808/*
809 * For each tracing session, update newly registered apps.
810 */
811static void update_ust_app(int app_sock)
812{
813 struct ltt_session *sess, *stmp;
814
815 session_lock_list();
816
817 /* For all tracing session(s) */
818 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
819 session_lock(sess);
820 if (sess->ust_session) {
821 ust_app_global_update(sess->ust_session, app_sock);
822 }
823 session_unlock(sess);
824 }
825
826 session_unlock_list();
827}
828
829/*
830 * This thread manage event coming from the kernel.
831 *
832 * Features supported in this thread:
833 * -) CPU Hotplug
834 */
835static void *thread_manage_kernel(void *data)
836{
837 int ret, i, pollfd, update_poll_flag = 1;
838 uint32_t revents, nb_fd;
839 char tmp;
840 struct lttng_poll_event events;
841
842 DBG("Thread manage kernel started");
843
844 ret = create_thread_poll_set(&events, 2);
845 if (ret < 0) {
846 goto error_poll_create;
847 }
848
849 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
850 if (ret < 0) {
851 goto error;
852 }
853
854 while (1) {
855 if (update_poll_flag == 1) {
856 /*
857 * Reset number of fd in the poll set. Always 2 since there is the thread
858 * quit pipe and the kernel pipe.
859 */
860 events.nb_fd = 2;
861
862 ret = update_kernel_poll(&events);
863 if (ret < 0) {
864 goto error;
865 }
866 update_poll_flag = 0;
867 }
868
869 nb_fd = LTTNG_POLL_GETNB(&events);
870
871 DBG("Thread kernel polling on %d fds", nb_fd);
872
873 /* Zeroed the poll events */
874 lttng_poll_reset(&events);
875
876 /* Poll infinite value of time */
877 restart:
878 ret = lttng_poll_wait(&events, -1);
879 if (ret < 0) {
880 /*
881 * Restart interrupted system call.
882 */
883 if (errno == EINTR) {
884 goto restart;
885 }
886 goto error;
887 } else if (ret == 0) {
888 /* Should not happen since timeout is infinite */
889 ERR("Return value of poll is 0 with an infinite timeout.\n"
890 "This should not have happened! Continuing...");
891 continue;
892 }
893
894 for (i = 0; i < nb_fd; i++) {
895 /* Fetch once the poll data */
896 revents = LTTNG_POLL_GETEV(&events, i);
897 pollfd = LTTNG_POLL_GETFD(&events, i);
898
899 /* Thread quit pipe has been closed. Killing thread. */
900 ret = check_thread_quit_pipe(pollfd, revents);
901 if (ret) {
902 goto error;
903 }
904
905 /* Check for data on kernel pipe */
906 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
907 ret = read(kernel_poll_pipe[0], &tmp, 1);
908 update_poll_flag = 1;
909 continue;
910 } else {
911 /*
912 * New CPU detected by the kernel. Adding kernel stream to
913 * kernel session and updating the kernel consumer
914 */
915 if (revents & LPOLLIN) {
916 ret = update_kernel_stream(&kconsumer_data, pollfd);
917 if (ret < 0) {
918 continue;
919 }
920 break;
921 /*
922 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
923 * and unregister kernel stream at this point.
924 */
925 }
926 }
927 }
928 }
929
930error:
931 lttng_poll_clean(&events);
932error_poll_create:
933 DBG("Kernel thread dying");
934 return NULL;
935}
936
937/*
938 * This thread manage the consumer error sent back to the session daemon.
939 */
940static void *thread_manage_consumer(void *data)
941{
942 int sock = -1, i, ret, pollfd;
943 uint32_t revents, nb_fd;
944 enum lttcomm_return_code code;
945 struct lttng_poll_event events;
946 struct consumer_data *consumer_data = data;
947
948 DBG("[thread] Manage consumer started");
949
950 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
951 if (ret < 0) {
952 goto error_listen;
953 }
954
955 /*
956 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
957 * Nothing more will be added to this poll set.
958 */
959 ret = create_thread_poll_set(&events, 2);
960 if (ret < 0) {
961 goto error_poll;
962 }
963
964 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
965 if (ret < 0) {
966 goto error;
967 }
968
969 nb_fd = LTTNG_POLL_GETNB(&events);
970
971 /* Inifinite blocking call, waiting for transmission */
972restart:
973 ret = lttng_poll_wait(&events, -1);
974 if (ret < 0) {
975 /*
976 * Restart interrupted system call.
977 */
978 if (errno == EINTR) {
979 goto restart;
980 }
981 goto error;
982 }
983
984 for (i = 0; i < nb_fd; i++) {
985 /* Fetch once the poll data */
986 revents = LTTNG_POLL_GETEV(&events, i);
987 pollfd = LTTNG_POLL_GETFD(&events, i);
988
989 /* Thread quit pipe has been closed. Killing thread. */
990 ret = check_thread_quit_pipe(pollfd, revents);
991 if (ret) {
992 goto error;
993 }
994
995 /* Event on the registration socket */
996 if (pollfd == consumer_data->err_sock) {
997 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
998 ERR("consumer err socket poll error");
999 goto error;
1000 }
1001 }
1002 }
1003
1004 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
1005 if (sock < 0) {
1006 goto error;
1007 }
1008
1009 DBG2("Receiving code from consumer err_sock");
1010
1011 /* Getting status code from kconsumerd */
1012 ret = lttcomm_recv_unix_sock(sock, &code,
1013 sizeof(enum lttcomm_return_code));
1014 if (ret <= 0) {
1015 goto error;
1016 }
1017
1018 if (code == CONSUMERD_COMMAND_SOCK_READY) {
1019 consumer_data->cmd_sock =
1020 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
1021 if (consumer_data->cmd_sock < 0) {
1022 sem_post(&consumer_data->sem);
1023 PERROR("consumer connect");
1024 goto error;
1025 }
1026 /* Signal condition to tell that the kconsumerd is ready */
1027 sem_post(&consumer_data->sem);
1028 DBG("consumer command socket ready");
1029 } else {
1030 ERR("consumer error when waiting for SOCK_READY : %s",
1031 lttcomm_get_readable_code(-code));
1032 goto error;
1033 }
1034
1035 /* Remove the kconsumerd error sock since we've established a connexion */
1036 ret = lttng_poll_del(&events, consumer_data->err_sock);
1037 if (ret < 0) {
1038 goto error;
1039 }
1040
1041 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1042 if (ret < 0) {
1043 goto error;
1044 }
1045
1046 /* Update number of fd */
1047 nb_fd = LTTNG_POLL_GETNB(&events);
1048
1049 /* Inifinite blocking call, waiting for transmission */
1050restart_poll:
1051 ret = lttng_poll_wait(&events, -1);
1052 if (ret < 0) {
1053 /*
1054 * Restart interrupted system call.
1055 */
1056 if (errno == EINTR) {
1057 goto restart_poll;
1058 }
1059 goto error;
1060 }
1061
1062 for (i = 0; i < nb_fd; i++) {
1063 /* Fetch once the poll data */
1064 revents = LTTNG_POLL_GETEV(&events, i);
1065 pollfd = LTTNG_POLL_GETFD(&events, i);
1066
1067 /* Thread quit pipe has been closed. Killing thread. */
1068 ret = check_thread_quit_pipe(pollfd, revents);
1069 if (ret) {
1070 goto error;
1071 }
1072
1073 /* Event on the kconsumerd socket */
1074 if (pollfd == sock) {
1075 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1076 ERR("consumer err socket second poll error");
1077 goto error;
1078 }
1079 }
1080 }
1081
1082 /* Wait for any kconsumerd error */
1083 ret = lttcomm_recv_unix_sock(sock, &code,
1084 sizeof(enum lttcomm_return_code));
1085 if (ret <= 0) {
1086 ERR("consumer closed the command socket");
1087 goto error;
1088 }
1089
1090 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1091
1092error:
1093 if (consumer_data->err_sock >= 0) {
1094 ret = close(consumer_data->err_sock);
1095 if (ret) {
1096 PERROR("close");
1097 }
1098 }
1099 if (consumer_data->cmd_sock >= 0) {
1100 ret = close(consumer_data->cmd_sock);
1101 if (ret) {
1102 PERROR("close");
1103 }
1104 }
1105 if (sock >= 0) {
1106 ret = close(sock);
1107 if (ret) {
1108 PERROR("close");
1109 }
1110 }
1111
1112 unlink(consumer_data->err_unix_sock_path);
1113 unlink(consumer_data->cmd_unix_sock_path);
1114 consumer_data->pid = 0;
1115
1116 lttng_poll_clean(&events);
1117error_poll:
1118error_listen:
1119 DBG("consumer thread cleanup completed");
1120
1121 return NULL;
1122}
1123
1124/*
1125 * This thread manage application communication.
1126 */
1127static void *thread_manage_apps(void *data)
1128{
1129 int i, ret, pollfd;
1130 uint32_t revents, nb_fd;
1131 struct ust_command ust_cmd;
1132 struct lttng_poll_event events;
1133
1134 DBG("[thread] Manage application started");
1135
1136 rcu_register_thread();
1137 rcu_thread_online();
1138
1139 ret = create_thread_poll_set(&events, 2);
1140 if (ret < 0) {
1141 goto error_poll_create;
1142 }
1143
1144 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1145 if (ret < 0) {
1146 goto error;
1147 }
1148
1149 while (1) {
1150 /* Zeroed the events structure */
1151 lttng_poll_reset(&events);
1152
1153 nb_fd = LTTNG_POLL_GETNB(&events);
1154
1155 DBG("Apps thread polling on %d fds", nb_fd);
1156
1157 /* Inifinite blocking call, waiting for transmission */
1158 restart:
1159 ret = lttng_poll_wait(&events, -1);
1160 if (ret < 0) {
1161 /*
1162 * Restart interrupted system call.
1163 */
1164 if (errno == EINTR) {
1165 goto restart;
1166 }
1167 goto error;
1168 }
1169
1170 for (i = 0; i < nb_fd; i++) {
1171 /* Fetch once the poll data */
1172 revents = LTTNG_POLL_GETEV(&events, i);
1173 pollfd = LTTNG_POLL_GETFD(&events, i);
1174
1175 /* Thread quit pipe has been closed. Killing thread. */
1176 ret = check_thread_quit_pipe(pollfd, revents);
1177 if (ret) {
1178 goto error;
1179 }
1180
1181 /* Inspect the apps cmd pipe */
1182 if (pollfd == apps_cmd_pipe[0]) {
1183 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1184 ERR("Apps command pipe error");
1185 goto error;
1186 } else if (revents & LPOLLIN) {
1187 /* Empty pipe */
1188 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1189 if (ret < 0 || ret < sizeof(ust_cmd)) {
1190 PERROR("read apps cmd pipe");
1191 goto error;
1192 }
1193
1194 /* Register applicaton to the session daemon */
1195 ret = ust_app_register(&ust_cmd.reg_msg,
1196 ust_cmd.sock);
1197 if (ret == -ENOMEM) {
1198 goto error;
1199 } else if (ret < 0) {
1200 break;
1201 }
1202
1203 /*
1204 * Validate UST version compatibility.
1205 */
1206 ret = ust_app_validate_version(ust_cmd.sock);
1207 if (ret >= 0) {
1208 /*
1209 * Add channel(s) and event(s) to newly registered apps
1210 * from lttng global UST domain.
1211 */
1212 update_ust_app(ust_cmd.sock);
1213 }
1214
1215 ret = ust_app_register_done(ust_cmd.sock);
1216 if (ret < 0) {
1217 /*
1218 * If the registration is not possible, we simply
1219 * unregister the apps and continue
1220 */
1221 ust_app_unregister(ust_cmd.sock);
1222 } else {
1223 /*
1224 * We just need here to monitor the close of the UST
1225 * socket and poll set monitor those by default.
1226 * Listen on POLLIN (even if we never expect any
1227 * data) to ensure that hangup wakes us.
1228 */
1229 ret = lttng_poll_add(&events, ust_cmd.sock, LPOLLIN);
1230 if (ret < 0) {
1231 goto error;
1232 }
1233
1234 DBG("Apps with sock %d added to poll set",
1235 ust_cmd.sock);
1236 }
1237
1238 break;
1239 }
1240 } else {
1241 /*
1242 * At this point, we know that a registered application made
1243 * the event at poll_wait.
1244 */
1245 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1246 /* Removing from the poll set */
1247 ret = lttng_poll_del(&events, pollfd);
1248 if (ret < 0) {
1249 goto error;
1250 }
1251
1252 /* Socket closed on remote end. */
1253 ust_app_unregister(pollfd);
1254 break;
1255 }
1256 }
1257 }
1258 }
1259
1260error:
1261 lttng_poll_clean(&events);
1262error_poll_create:
1263 DBG("Application communication apps thread cleanup complete");
1264 rcu_thread_offline();
1265 rcu_unregister_thread();
1266 return NULL;
1267}
1268
1269/*
1270 * Dispatch request from the registration threads to the application
1271 * communication thread.
1272 */
1273static void *thread_dispatch_ust_registration(void *data)
1274{
1275 int ret;
1276 struct cds_wfq_node *node;
1277 struct ust_command *ust_cmd = NULL;
1278
1279 DBG("[thread] Dispatch UST command started");
1280
1281 while (!dispatch_thread_exit) {
1282 /* Atomically prepare the queue futex */
1283 futex_nto1_prepare(&ust_cmd_queue.futex);
1284
1285 do {
1286 /* Dequeue command for registration */
1287 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1288 if (node == NULL) {
1289 DBG("Woken up but nothing in the UST command queue");
1290 /* Continue thread execution */
1291 break;
1292 }
1293
1294 ust_cmd = caa_container_of(node, struct ust_command, node);
1295
1296 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1297 " gid:%d sock:%d name:%s (version %d.%d)",
1298 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1299 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1300 ust_cmd->sock, ust_cmd->reg_msg.name,
1301 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1302 /*
1303 * Inform apps thread of the new application registration. This
1304 * call is blocking so we can be assured that the data will be read
1305 * at some point in time or wait to the end of the world :)
1306 */
1307 ret = write(apps_cmd_pipe[1], ust_cmd,
1308 sizeof(struct ust_command));
1309 if (ret < 0) {
1310 PERROR("write apps cmd pipe");
1311 if (errno == EBADF) {
1312 /*
1313 * We can't inform the application thread to process
1314 * registration. We will exit or else application
1315 * registration will not occur and tracing will never
1316 * start.
1317 */
1318 goto error;
1319 }
1320 }
1321 free(ust_cmd);
1322 } while (node != NULL);
1323
1324 /* Futex wait on queue. Blocking call on futex() */
1325 futex_nto1_wait(&ust_cmd_queue.futex);
1326 }
1327
1328error:
1329 DBG("Dispatch thread dying");
1330 return NULL;
1331}
1332
1333/*
1334 * This thread manage application registration.
1335 */
1336static void *thread_registration_apps(void *data)
1337{
1338 int sock = -1, i, ret, pollfd;
1339 uint32_t revents, nb_fd;
1340 struct lttng_poll_event events;
1341 /*
1342 * Get allocated in this thread, enqueued to a global queue, dequeued and
1343 * freed in the manage apps thread.
1344 */
1345 struct ust_command *ust_cmd = NULL;
1346
1347 DBG("[thread] Manage application registration started");
1348
1349 ret = lttcomm_listen_unix_sock(apps_sock);
1350 if (ret < 0) {
1351 goto error_listen;
1352 }
1353
1354 /*
1355 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1356 * more will be added to this poll set.
1357 */
1358 ret = create_thread_poll_set(&events, 2);
1359 if (ret < 0) {
1360 goto error_create_poll;
1361 }
1362
1363 /* Add the application registration socket */
1364 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1365 if (ret < 0) {
1366 goto error_poll_add;
1367 }
1368
1369 /* Notify all applications to register */
1370 ret = notify_ust_apps(1);
1371 if (ret < 0) {
1372 ERR("Failed to notify applications or create the wait shared memory.\n"
1373 "Execution continues but there might be problem for already\n"
1374 "running applications that wishes to register.");
1375 }
1376
1377 while (1) {
1378 DBG("Accepting application registration");
1379
1380 nb_fd = LTTNG_POLL_GETNB(&events);
1381
1382 /* Inifinite blocking call, waiting for transmission */
1383 restart:
1384 ret = lttng_poll_wait(&events, -1);
1385 if (ret < 0) {
1386 /*
1387 * Restart interrupted system call.
1388 */
1389 if (errno == EINTR) {
1390 goto restart;
1391 }
1392 goto error;
1393 }
1394
1395 for (i = 0; i < nb_fd; i++) {
1396 /* Fetch once the poll data */
1397 revents = LTTNG_POLL_GETEV(&events, i);
1398 pollfd = LTTNG_POLL_GETFD(&events, i);
1399
1400 /* Thread quit pipe has been closed. Killing thread. */
1401 ret = check_thread_quit_pipe(pollfd, revents);
1402 if (ret) {
1403 goto error;
1404 }
1405
1406 /* Event on the registration socket */
1407 if (pollfd == apps_sock) {
1408 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1409 ERR("Register apps socket poll error");
1410 goto error;
1411 } else if (revents & LPOLLIN) {
1412 sock = lttcomm_accept_unix_sock(apps_sock);
1413 if (sock < 0) {
1414 goto error;
1415 }
1416
1417 /* Create UST registration command for enqueuing */
1418 ust_cmd = zmalloc(sizeof(struct ust_command));
1419 if (ust_cmd == NULL) {
1420 PERROR("ust command zmalloc");
1421 goto error;
1422 }
1423
1424 /*
1425 * Using message-based transmissions to ensure we don't
1426 * have to deal with partially received messages.
1427 */
1428 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
1429 if (ret < 0) {
1430 ERR("Exhausted file descriptors allowed for applications.");
1431 free(ust_cmd);
1432 ret = close(sock);
1433 if (ret) {
1434 PERROR("close");
1435 }
1436 sock = -1;
1437 continue;
1438 }
1439 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1440 sizeof(struct ust_register_msg));
1441 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1442 if (ret < 0) {
1443 PERROR("lttcomm_recv_unix_sock register apps");
1444 } else {
1445 ERR("Wrong size received on apps register");
1446 }
1447 free(ust_cmd);
1448 ret = close(sock);
1449 if (ret) {
1450 PERROR("close");
1451 }
1452 lttng_fd_put(LTTNG_FD_APPS, 1);
1453 sock = -1;
1454 continue;
1455 }
1456
1457 ust_cmd->sock = sock;
1458 sock = -1;
1459
1460 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1461 " gid:%d sock:%d name:%s (version %d.%d)",
1462 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1463 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1464 ust_cmd->sock, ust_cmd->reg_msg.name,
1465 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1466
1467 /*
1468 * Lock free enqueue the registration request. The red pill
1469 * has been taken! This apps will be part of the *system*.
1470 */
1471 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1472
1473 /*
1474 * Wake the registration queue futex. Implicit memory
1475 * barrier with the exchange in cds_wfq_enqueue.
1476 */
1477 futex_nto1_wake(&ust_cmd_queue.futex);
1478 }
1479 }
1480 }
1481 }
1482
1483error:
1484 /* Notify that the registration thread is gone */
1485 notify_ust_apps(0);
1486
1487 if (apps_sock >= 0) {
1488 ret = close(apps_sock);
1489 if (ret) {
1490 PERROR("close");
1491 }
1492 }
1493 if (sock >= 0) {
1494 ret = close(sock);
1495 if (ret) {
1496 PERROR("close");
1497 }
1498 lttng_fd_put(LTTNG_FD_APPS, 1);
1499 }
1500 unlink(apps_unix_sock_path);
1501
1502error_poll_add:
1503 lttng_poll_clean(&events);
1504error_listen:
1505error_create_poll:
1506 DBG("UST Registration thread cleanup complete");
1507
1508 return NULL;
1509}
1510
1511/*
1512 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1513 * exec or it will fails.
1514 */
1515static int spawn_consumer_thread(struct consumer_data *consumer_data)
1516{
1517 int ret;
1518 struct timespec timeout;
1519
1520 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1521 timeout.tv_nsec = 0;
1522
1523 /* Setup semaphore */
1524 ret = sem_init(&consumer_data->sem, 0, 0);
1525 if (ret < 0) {
1526 PERROR("sem_init consumer semaphore");
1527 goto error;
1528 }
1529
1530 ret = pthread_create(&consumer_data->thread, NULL,
1531 thread_manage_consumer, consumer_data);
1532 if (ret != 0) {
1533 PERROR("pthread_create consumer");
1534 ret = -1;
1535 goto error;
1536 }
1537
1538 /* Get time for sem_timedwait absolute timeout */
1539 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1540 if (ret < 0) {
1541 PERROR("clock_gettime spawn consumer");
1542 /* Infinite wait for the kconsumerd thread to be ready */
1543 ret = sem_wait(&consumer_data->sem);
1544 } else {
1545 /* Normal timeout if the gettime was successful */
1546 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1547 ret = sem_timedwait(&consumer_data->sem, &timeout);
1548 }
1549
1550 if (ret < 0) {
1551 if (errno == ETIMEDOUT) {
1552 /*
1553 * Call has timed out so we kill the kconsumerd_thread and return
1554 * an error.
1555 */
1556 ERR("The consumer thread was never ready. Killing it");
1557 ret = pthread_cancel(consumer_data->thread);
1558 if (ret < 0) {
1559 PERROR("pthread_cancel consumer thread");
1560 }
1561 } else {
1562 PERROR("semaphore wait failed consumer thread");
1563 }
1564 goto error;
1565 }
1566
1567 pthread_mutex_lock(&consumer_data->pid_mutex);
1568 if (consumer_data->pid == 0) {
1569 ERR("Kconsumerd did not start");
1570 pthread_mutex_unlock(&consumer_data->pid_mutex);
1571 goto error;
1572 }
1573 pthread_mutex_unlock(&consumer_data->pid_mutex);
1574
1575 return 0;
1576
1577error:
1578 return ret;
1579}
1580
1581/*
1582 * Join consumer thread
1583 */
1584static int join_consumer_thread(struct consumer_data *consumer_data)
1585{
1586 void *status;
1587 int ret;
1588
1589 if (consumer_data->pid != 0) {
1590 ret = kill(consumer_data->pid, SIGTERM);
1591 if (ret) {
1592 ERR("Error killing consumer daemon");
1593 return ret;
1594 }
1595 return pthread_join(consumer_data->thread, &status);
1596 } else {
1597 return 0;
1598 }
1599}
1600
1601/*
1602 * Fork and exec a consumer daemon (consumerd).
1603 *
1604 * Return pid if successful else -1.
1605 */
1606static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1607{
1608 int ret;
1609 pid_t pid;
1610 const char *consumer_to_use;
1611 const char *verbosity;
1612 struct stat st;
1613
1614 DBG("Spawning consumerd");
1615
1616 pid = fork();
1617 if (pid == 0) {
1618 /*
1619 * Exec consumerd.
1620 */
1621 if (opt_verbose_consumer) {
1622 verbosity = "--verbose";
1623 } else {
1624 verbosity = "--quiet";
1625 }
1626 switch (consumer_data->type) {
1627 case LTTNG_CONSUMER_KERNEL:
1628 /*
1629 * Find out which consumerd to execute. We will first try the
1630 * 64-bit path, then the sessiond's installation directory, and
1631 * fallback on the 32-bit one,
1632 */
1633 DBG3("Looking for a kernel consumer at these locations:");
1634 DBG3(" 1) %s", consumerd64_bin);
1635 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1636 DBG3(" 3) %s", consumerd32_bin);
1637 if (stat(consumerd64_bin, &st) == 0) {
1638 DBG3("Found location #1");
1639 consumer_to_use = consumerd64_bin;
1640 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1641 DBG3("Found location #2");
1642 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1643 } else if (stat(consumerd32_bin, &st) == 0) {
1644 DBG3("Found location #3");
1645 consumer_to_use = consumerd32_bin;
1646 } else {
1647 DBG("Could not find any valid consumerd executable");
1648 break;
1649 }
1650 DBG("Using kernel consumer at: %s", consumer_to_use);
1651 execl(consumer_to_use,
1652 "lttng-consumerd", verbosity, "-k",
1653 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1654 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1655 NULL);
1656 break;
1657 case LTTNG_CONSUMER64_UST:
1658 {
1659 char *tmpnew = NULL;
1660
1661 if (consumerd64_libdir[0] != '\0') {
1662 char *tmp;
1663 size_t tmplen;
1664
1665 tmp = getenv("LD_LIBRARY_PATH");
1666 if (!tmp) {
1667 tmp = "";
1668 }
1669 tmplen = strlen("LD_LIBRARY_PATH=")
1670 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1671 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1672 if (!tmpnew) {
1673 ret = -ENOMEM;
1674 goto error;
1675 }
1676 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1677 strcat(tmpnew, consumerd64_libdir);
1678 if (tmp[0] != '\0') {
1679 strcat(tmpnew, ":");
1680 strcat(tmpnew, tmp);
1681 }
1682 ret = putenv(tmpnew);
1683 if (ret) {
1684 ret = -errno;
1685 goto error;
1686 }
1687 }
1688 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1689 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1690 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1691 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1692 NULL);
1693 if (consumerd64_libdir[0] != '\0') {
1694 free(tmpnew);
1695 }
1696 if (ret) {
1697 goto error;
1698 }
1699 break;
1700 }
1701 case LTTNG_CONSUMER32_UST:
1702 {
1703 char *tmpnew = NULL;
1704
1705 if (consumerd32_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(consumerd32_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, consumerd32_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 32-bit UST consumer at: %s", consumerd32_bin);
1733 ret = execl(consumerd32_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 (consumerd32_libdir[0] != '\0') {
1738 free(tmpnew);
1739 }
1740 if (ret) {
1741 goto error;
1742 }
1743 break;
1744 }
1745 default:
1746 PERROR("unknown consumer type");
1747 exit(EXIT_FAILURE);
1748 }
1749 if (errno != 0) {
1750 PERROR("kernel start consumer exec");
1751 }
1752 exit(EXIT_FAILURE);
1753 } else if (pid > 0) {
1754 ret = pid;
1755 } else {
1756 PERROR("start consumer fork");
1757 ret = -errno;
1758 }
1759error:
1760 return ret;
1761}
1762
1763/*
1764 * Spawn the consumerd daemon and session daemon thread.
1765 */
1766static int start_consumerd(struct consumer_data *consumer_data)
1767{
1768 int ret;
1769
1770 pthread_mutex_lock(&consumer_data->pid_mutex);
1771 if (consumer_data->pid != 0) {
1772 pthread_mutex_unlock(&consumer_data->pid_mutex);
1773 goto end;
1774 }
1775
1776 ret = spawn_consumerd(consumer_data);
1777 if (ret < 0) {
1778 ERR("Spawning consumerd failed");
1779 pthread_mutex_unlock(&consumer_data->pid_mutex);
1780 goto error;
1781 }
1782
1783 /* Setting up the consumer_data pid */
1784 consumer_data->pid = ret;
1785 DBG2("Consumer pid %d", consumer_data->pid);
1786 pthread_mutex_unlock(&consumer_data->pid_mutex);
1787
1788 DBG2("Spawning consumer control thread");
1789 ret = spawn_consumer_thread(consumer_data);
1790 if (ret < 0) {
1791 ERR("Fatal error spawning consumer control thread");
1792 goto error;
1793 }
1794
1795end:
1796 return 0;
1797
1798error:
1799 return ret;
1800}
1801
1802/*
1803 * Check version of the lttng-modules.
1804 */
1805static int validate_lttng_modules_version(void)
1806{
1807 return kernel_validate_version(kernel_tracer_fd);
1808}
1809
1810/*
1811 * Setup necessary data for kernel tracer action.
1812 */
1813static int init_kernel_tracer(void)
1814{
1815 int ret;
1816
1817 /* Modprobe lttng kernel modules */
1818 ret = modprobe_lttng_control();
1819 if (ret < 0) {
1820 goto error;
1821 }
1822
1823 /* Open debugfs lttng */
1824 kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
1825 if (kernel_tracer_fd < 0) {
1826 DBG("Failed to open %s", module_proc_lttng);
1827 ret = -1;
1828 goto error_open;
1829 }
1830
1831 /* Validate kernel version */
1832 ret = validate_lttng_modules_version();
1833 if (ret < 0) {
1834 goto error_version;
1835 }
1836
1837 ret = modprobe_lttng_data();
1838 if (ret < 0) {
1839 goto error_modules;
1840 }
1841
1842 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1843 return 0;
1844
1845error_version:
1846 modprobe_remove_lttng_control();
1847 ret = close(kernel_tracer_fd);
1848 if (ret) {
1849 PERROR("close");
1850 }
1851 kernel_tracer_fd = -1;
1852 return LTTCOMM_KERN_VERSION;
1853
1854error_modules:
1855 ret = close(kernel_tracer_fd);
1856 if (ret) {
1857 PERROR("close");
1858 }
1859
1860error_open:
1861 modprobe_remove_lttng_control();
1862
1863error:
1864 WARN("No kernel tracer available");
1865 kernel_tracer_fd = -1;
1866 if (!is_root) {
1867 return LTTCOMM_NEED_ROOT_SESSIOND;
1868 } else {
1869 return LTTCOMM_KERN_NA;
1870 }
1871}
1872
1873/*
1874 * Init tracing by creating trace directory and sending fds kernel consumer.
1875 */
1876static int init_kernel_tracing(struct ltt_kernel_session *session)
1877{
1878 int ret = 0;
1879
1880 if (session->consumer_fds_sent == 0) {
1881 /*
1882 * Assign default kernel consumer socket if no consumer assigned to the
1883 * kernel session. At this point, it's NOT supposed to be -1 but this is
1884 * an extra security check.
1885 */
1886 if (session->consumer_fd < 0) {
1887 session->consumer_fd = kconsumer_data.cmd_sock;
1888 }
1889
1890 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1891 if (ret < 0) {
1892 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1893 goto error;
1894 }
1895
1896 session->consumer_fds_sent = 1;
1897 }
1898
1899error:
1900 return ret;
1901}
1902
1903/*
1904 * Create an UST session and add it to the session ust list.
1905 */
1906static int create_ust_session(struct ltt_session *session,
1907 struct lttng_domain *domain)
1908{
1909 struct ltt_ust_session *lus = NULL;
1910 int ret;
1911
1912 switch (domain->type) {
1913 case LTTNG_DOMAIN_UST:
1914 break;
1915 default:
1916 ret = LTTCOMM_UNKNOWN_DOMAIN;
1917 goto error;
1918 }
1919
1920 DBG("Creating UST session");
1921
1922 lus = trace_ust_create_session(session->path, session->id, domain);
1923 if (lus == NULL) {
1924 ret = LTTCOMM_UST_SESS_FAIL;
1925 goto error;
1926 }
1927
1928 ret = run_as_mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1929 session->uid, session->gid);
1930 if (ret < 0) {
1931 if (ret != -EEXIST) {
1932 ERR("Trace directory creation error");
1933 ret = LTTCOMM_UST_SESS_FAIL;
1934 goto error;
1935 }
1936 }
1937
1938 /* The domain type dictate different actions on session creation */
1939 switch (domain->type) {
1940 case LTTNG_DOMAIN_UST:
1941 /* No ustctl for the global UST domain */
1942 break;
1943 default:
1944 ERR("Unknown UST domain on create session %d", domain->type);
1945 goto error;
1946 }
1947 lus->uid = session->uid;
1948 lus->gid = session->gid;
1949 session->ust_session = lus;
1950
1951 return LTTCOMM_OK;
1952
1953error:
1954 free(lus);
1955 return ret;
1956}
1957
1958/*
1959 * Create a kernel tracer session then create the default channel.
1960 */
1961static int create_kernel_session(struct ltt_session *session)
1962{
1963 int ret;
1964
1965 DBG("Creating kernel session");
1966
1967 ret = kernel_create_session(session, kernel_tracer_fd);
1968 if (ret < 0) {
1969 ret = LTTCOMM_KERN_SESS_FAIL;
1970 goto error;
1971 }
1972
1973 /* Set kernel consumer socket fd */
1974 if (kconsumer_data.cmd_sock >= 0) {
1975 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1976 }
1977
1978 ret = run_as_mkdir_recursive(session->kernel_session->trace_path,
1979 S_IRWXU | S_IRWXG, session->uid, session->gid);
1980 if (ret < 0) {
1981 if (ret != -EEXIST) {
1982 ERR("Trace directory creation error");
1983 goto error;
1984 }
1985 }
1986 session->kernel_session->uid = session->uid;
1987 session->kernel_session->gid = session->gid;
1988
1989error:
1990 return ret;
1991}
1992
1993/*
1994 * Check if the UID or GID match the session. Root user has access to all
1995 * sessions.
1996 */
1997static int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid)
1998{
1999 if (uid != session->uid && gid != session->gid && uid != 0) {
2000 return 0;
2001 } else {
2002 return 1;
2003 }
2004}
2005
2006static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
2007{
2008 unsigned int i = 0;
2009 struct ltt_session *session;
2010
2011 DBG("Counting number of available session for UID %d GID %d",
2012 uid, gid);
2013 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2014 /*
2015 * Only list the sessions the user can control.
2016 */
2017 if (!session_access_ok(session, uid, gid)) {
2018 continue;
2019 }
2020 i++;
2021 }
2022 return i;
2023}
2024
2025/*
2026 * Using the session list, filled a lttng_session array to send back to the
2027 * client for session listing.
2028 *
2029 * The session list lock MUST be acquired before calling this function. Use
2030 * session_lock_list() and session_unlock_list().
2031 */
2032static void list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2033 gid_t gid)
2034{
2035 unsigned int i = 0;
2036 struct ltt_session *session;
2037
2038 DBG("Getting all available session for UID %d GID %d",
2039 uid, gid);
2040 /*
2041 * Iterate over session list and append data after the control struct in
2042 * the buffer.
2043 */
2044 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2045 /*
2046 * Only list the sessions the user can control.
2047 */
2048 if (!session_access_ok(session, uid, gid)) {
2049 continue;
2050 }
2051 strncpy(sessions[i].path, session->path, PATH_MAX);
2052 sessions[i].path[PATH_MAX - 1] = '\0';
2053 strncpy(sessions[i].name, session->name, NAME_MAX);
2054 sessions[i].name[NAME_MAX - 1] = '\0';
2055 sessions[i].enabled = session->enabled;
2056 i++;
2057 }
2058}
2059
2060/*
2061 * Fill lttng_channel array of all channels.
2062 */
2063static void list_lttng_channels(int domain, struct ltt_session *session,
2064 struct lttng_channel *channels)
2065{
2066 int i = 0;
2067 struct ltt_kernel_channel *kchan;
2068
2069 DBG("Listing channels for session %s", session->name);
2070
2071 switch (domain) {
2072 case LTTNG_DOMAIN_KERNEL:
2073 /* Kernel channels */
2074 if (session->kernel_session != NULL) {
2075 cds_list_for_each_entry(kchan,
2076 &session->kernel_session->channel_list.head, list) {
2077 /* Copy lttng_channel struct to array */
2078 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2079 channels[i].enabled = kchan->enabled;
2080 i++;
2081 }
2082 }
2083 break;
2084 case LTTNG_DOMAIN_UST:
2085 {
2086 struct lttng_ht_iter iter;
2087 struct ltt_ust_channel *uchan;
2088
2089 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
2090 &iter.iter, uchan, node.node) {
2091 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2092 channels[i].attr.overwrite = uchan->attr.overwrite;
2093 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2094 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2095 channels[i].attr.switch_timer_interval =
2096 uchan->attr.switch_timer_interval;
2097 channels[i].attr.read_timer_interval =
2098 uchan->attr.read_timer_interval;
2099 channels[i].enabled = uchan->enabled;
2100 switch (uchan->attr.output) {
2101 case LTTNG_UST_MMAP:
2102 default:
2103 channels[i].attr.output = LTTNG_EVENT_MMAP;
2104 break;
2105 }
2106 i++;
2107 }
2108 break;
2109 }
2110 default:
2111 break;
2112 }
2113}
2114
2115/*
2116 * Create a list of ust global domain events.
2117 */
2118static int list_lttng_ust_global_events(char *channel_name,
2119 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2120{
2121 int i = 0, ret = 0;
2122 unsigned int nb_event = 0;
2123 struct lttng_ht_iter iter;
2124 struct lttng_ht_node_str *node;
2125 struct ltt_ust_channel *uchan;
2126 struct ltt_ust_event *uevent;
2127 struct lttng_event *tmp;
2128
2129 DBG("Listing UST global events for channel %s", channel_name);
2130
2131 rcu_read_lock();
2132
2133 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2134 node = lttng_ht_iter_get_node_str(&iter);
2135 if (node == NULL) {
2136 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2137 goto error;
2138 }
2139
2140 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2141
2142 nb_event += lttng_ht_get_count(uchan->events);
2143
2144 if (nb_event == 0) {
2145 ret = nb_event;
2146 goto error;
2147 }
2148
2149 DBG3("Listing UST global %d events", nb_event);
2150
2151 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2152 if (tmp == NULL) {
2153 ret = -LTTCOMM_FATAL;
2154 goto error;
2155 }
2156
2157 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2158 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2159 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2160 tmp[i].enabled = uevent->enabled;
2161 switch (uevent->attr.instrumentation) {
2162 case LTTNG_UST_TRACEPOINT:
2163 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2164 break;
2165 case LTTNG_UST_PROBE:
2166 tmp[i].type = LTTNG_EVENT_PROBE;
2167 break;
2168 case LTTNG_UST_FUNCTION:
2169 tmp[i].type = LTTNG_EVENT_FUNCTION;
2170 break;
2171 }
2172 tmp[i].loglevel = uevent->attr.loglevel;
2173 switch (uevent->attr.loglevel_type) {
2174 case LTTNG_UST_LOGLEVEL_ALL:
2175 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2176 break;
2177 case LTTNG_UST_LOGLEVEL_RANGE:
2178 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
2179 break;
2180 case LTTNG_UST_LOGLEVEL_SINGLE:
2181 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
2182 break;
2183 }
2184 i++;
2185 }
2186
2187 ret = nb_event;
2188 *events = tmp;
2189
2190error:
2191 rcu_read_unlock();
2192 return ret;
2193}
2194
2195/*
2196 * Fill lttng_event array of all kernel events in the channel.
2197 */
2198static int list_lttng_kernel_events(char *channel_name,
2199 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2200{
2201 int i = 0, ret;
2202 unsigned int nb_event;
2203 struct ltt_kernel_event *event;
2204 struct ltt_kernel_channel *kchan;
2205
2206 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2207 if (kchan == NULL) {
2208 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2209 goto error;
2210 }
2211
2212 nb_event = kchan->event_count;
2213
2214 DBG("Listing events for channel %s", kchan->channel->name);
2215
2216 if (nb_event == 0) {
2217 ret = nb_event;
2218 goto error;
2219 }
2220
2221 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2222 if (*events == NULL) {
2223 ret = LTTCOMM_FATAL;
2224 goto error;
2225 }
2226
2227 /* Kernel channels */
2228 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2229 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2230 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2231 (*events)[i].enabled = event->enabled;
2232 switch (event->event->instrumentation) {
2233 case LTTNG_KERNEL_TRACEPOINT:
2234 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2235 break;
2236 case LTTNG_KERNEL_KPROBE:
2237 case LTTNG_KERNEL_KRETPROBE:
2238 (*events)[i].type = LTTNG_EVENT_PROBE;
2239 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2240 sizeof(struct lttng_kernel_kprobe));
2241 break;
2242 case LTTNG_KERNEL_FUNCTION:
2243 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2244 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2245 sizeof(struct lttng_kernel_function));
2246 break;
2247 case LTTNG_KERNEL_NOOP:
2248 (*events)[i].type = LTTNG_EVENT_NOOP;
2249 break;
2250 case LTTNG_KERNEL_SYSCALL:
2251 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2252 break;
2253 case LTTNG_KERNEL_ALL:
2254 assert(0);
2255 break;
2256 }
2257 i++;
2258 }
2259
2260 return nb_event;
2261
2262error:
2263 return ret;
2264}
2265
2266/*
2267 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2268 */
2269static int cmd_disable_channel(struct ltt_session *session,
2270 int domain, char *channel_name)
2271{
2272 int ret;
2273 struct ltt_ust_session *usess;
2274
2275 usess = session->ust_session;
2276
2277 switch (domain) {
2278 case LTTNG_DOMAIN_KERNEL:
2279 {
2280 ret = channel_kernel_disable(session->kernel_session,
2281 channel_name);
2282 if (ret != LTTCOMM_OK) {
2283 goto error;
2284 }
2285
2286 kernel_wait_quiescent(kernel_tracer_fd);
2287 break;
2288 }
2289 case LTTNG_DOMAIN_UST:
2290 {
2291 struct ltt_ust_channel *uchan;
2292 struct lttng_ht *chan_ht;
2293
2294 chan_ht = usess->domain_global.channels;
2295
2296 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2297 if (uchan == NULL) {
2298 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2299 goto error;
2300 }
2301
2302 ret = channel_ust_disable(usess, domain, uchan);
2303 if (ret != LTTCOMM_OK) {
2304 goto error;
2305 }
2306 break;
2307 }
2308#if 0
2309 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2310 case LTTNG_DOMAIN_UST_EXEC_NAME:
2311 case LTTNG_DOMAIN_UST_PID:
2312#endif
2313 default:
2314 ret = LTTCOMM_UNKNOWN_DOMAIN;
2315 goto error;
2316 }
2317
2318 ret = LTTCOMM_OK;
2319
2320error:
2321 return ret;
2322}
2323
2324/*
2325 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2326 */
2327static int cmd_enable_channel(struct ltt_session *session,
2328 int domain, struct lttng_channel *attr)
2329{
2330 int ret;
2331 struct ltt_ust_session *usess = session->ust_session;
2332 struct lttng_ht *chan_ht;
2333
2334 DBG("Enabling channel %s for session %s", attr->name, session->name);
2335
2336 switch (domain) {
2337 case LTTNG_DOMAIN_KERNEL:
2338 {
2339 struct ltt_kernel_channel *kchan;
2340
2341 kchan = trace_kernel_get_channel_by_name(attr->name,
2342 session->kernel_session);
2343 if (kchan == NULL) {
2344 ret = channel_kernel_create(session->kernel_session,
2345 attr, kernel_poll_pipe[1]);
2346 } else {
2347 ret = channel_kernel_enable(session->kernel_session, kchan);
2348 }
2349
2350 if (ret != LTTCOMM_OK) {
2351 goto error;
2352 }
2353
2354 kernel_wait_quiescent(kernel_tracer_fd);
2355 break;
2356 }
2357 case LTTNG_DOMAIN_UST:
2358 {
2359 struct ltt_ust_channel *uchan;
2360
2361 chan_ht = usess->domain_global.channels;
2362
2363 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2364 if (uchan == NULL) {
2365 ret = channel_ust_create(usess, domain, attr);
2366 } else {
2367 ret = channel_ust_enable(usess, domain, uchan);
2368 }
2369 break;
2370 }
2371#if 0
2372 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2373 case LTTNG_DOMAIN_UST_EXEC_NAME:
2374 case LTTNG_DOMAIN_UST_PID:
2375#endif
2376 default:
2377 ret = LTTCOMM_UNKNOWN_DOMAIN;
2378 goto error;
2379 }
2380
2381error:
2382 return ret;
2383}
2384
2385/*
2386 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2387 */
2388static int cmd_disable_event(struct ltt_session *session, int domain,
2389 char *channel_name, char *event_name)
2390{
2391 int ret;
2392
2393 switch (domain) {
2394 case LTTNG_DOMAIN_KERNEL:
2395 {
2396 struct ltt_kernel_channel *kchan;
2397 struct ltt_kernel_session *ksess;
2398
2399 ksess = session->kernel_session;
2400
2401 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2402 if (kchan == NULL) {
2403 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2404 goto error;
2405 }
2406
2407 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2408 if (ret != LTTCOMM_OK) {
2409 goto error;
2410 }
2411
2412 kernel_wait_quiescent(kernel_tracer_fd);
2413 break;
2414 }
2415 case LTTNG_DOMAIN_UST:
2416 {
2417 struct ltt_ust_channel *uchan;
2418 struct ltt_ust_session *usess;
2419
2420 usess = session->ust_session;
2421
2422 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2423 channel_name);
2424 if (uchan == NULL) {
2425 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2426 goto error;
2427 }
2428
2429 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2430 if (ret != LTTCOMM_OK) {
2431 goto error;
2432 }
2433
2434 DBG3("Disable UST event %s in channel %s completed", event_name,
2435 channel_name);
2436 break;
2437 }
2438#if 0
2439 case LTTNG_DOMAIN_UST_EXEC_NAME:
2440 case LTTNG_DOMAIN_UST_PID:
2441 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2442#endif
2443 default:
2444 ret = LTTCOMM_UND;
2445 goto error;
2446 }
2447
2448 ret = LTTCOMM_OK;
2449
2450error:
2451 return ret;
2452}
2453
2454/*
2455 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2456 */
2457static int cmd_disable_event_all(struct ltt_session *session, int domain,
2458 char *channel_name)
2459{
2460 int ret;
2461
2462 switch (domain) {
2463 case LTTNG_DOMAIN_KERNEL:
2464 {
2465 struct ltt_kernel_session *ksess;
2466 struct ltt_kernel_channel *kchan;
2467
2468 ksess = session->kernel_session;
2469
2470 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2471 if (kchan == NULL) {
2472 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2473 goto error;
2474 }
2475
2476 ret = event_kernel_disable_all(ksess, kchan);
2477 if (ret != LTTCOMM_OK) {
2478 goto error;
2479 }
2480
2481 kernel_wait_quiescent(kernel_tracer_fd);
2482 break;
2483 }
2484 case LTTNG_DOMAIN_UST:
2485 {
2486 struct ltt_ust_session *usess;
2487 struct ltt_ust_channel *uchan;
2488
2489 usess = session->ust_session;
2490
2491 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2492 channel_name);
2493 if (uchan == NULL) {
2494 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2495 goto error;
2496 }
2497
2498 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2499 if (ret != 0) {
2500 goto error;
2501 }
2502
2503 DBG3("Disable all UST events in channel %s completed", channel_name);
2504
2505 break;
2506 }
2507#if 0
2508 case LTTNG_DOMAIN_UST_EXEC_NAME:
2509 case LTTNG_DOMAIN_UST_PID:
2510 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2511#endif
2512 default:
2513 ret = LTTCOMM_UND;
2514 goto error;
2515 }
2516
2517 ret = LTTCOMM_OK;
2518
2519error:
2520 return ret;
2521}
2522
2523/*
2524 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2525 */
2526static int cmd_add_context(struct ltt_session *session, int domain,
2527 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2528{
2529 int ret;
2530
2531 switch (domain) {
2532 case LTTNG_DOMAIN_KERNEL:
2533 /* Add kernel context to kernel tracer */
2534 ret = context_kernel_add(session->kernel_session, ctx,
2535 event_name, channel_name);
2536 if (ret != LTTCOMM_OK) {
2537 goto error;
2538 }
2539 break;
2540 case LTTNG_DOMAIN_UST:
2541 {
2542 struct ltt_ust_session *usess = session->ust_session;
2543
2544 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2545 if (ret != LTTCOMM_OK) {
2546 goto error;
2547 }
2548 break;
2549 }
2550#if 0
2551 case LTTNG_DOMAIN_UST_EXEC_NAME:
2552 case LTTNG_DOMAIN_UST_PID:
2553 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2554#endif
2555 default:
2556 ret = LTTCOMM_UND;
2557 goto error;
2558 }
2559
2560 ret = LTTCOMM_OK;
2561
2562error:
2563 return ret;
2564}
2565
2566/*
2567 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2568 */
2569static int cmd_enable_event(struct ltt_session *session, int domain,
2570 char *channel_name, struct lttng_event *event)
2571{
2572 int ret;
2573 struct lttng_channel *attr;
2574 struct ltt_ust_session *usess = session->ust_session;
2575
2576 switch (domain) {
2577 case LTTNG_DOMAIN_KERNEL:
2578 {
2579 struct ltt_kernel_channel *kchan;
2580
2581 kchan = trace_kernel_get_channel_by_name(channel_name,
2582 session->kernel_session);
2583 if (kchan == NULL) {
2584 attr = channel_new_default_attr(domain);
2585 if (attr == NULL) {
2586 ret = LTTCOMM_FATAL;
2587 goto error;
2588 }
2589 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2590
2591 /* This call will notify the kernel thread */
2592 ret = channel_kernel_create(session->kernel_session,
2593 attr, kernel_poll_pipe[1]);
2594 if (ret != LTTCOMM_OK) {
2595 free(attr);
2596 goto error;
2597 }
2598 free(attr);
2599 }
2600
2601 /* Get the newly created kernel channel pointer */
2602 kchan = trace_kernel_get_channel_by_name(channel_name,
2603 session->kernel_session);
2604 if (kchan == NULL) {
2605 /* This sould not happen... */
2606 ret = LTTCOMM_FATAL;
2607 goto error;
2608 }
2609
2610 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2611 event);
2612 if (ret != LTTCOMM_OK) {
2613 goto error;
2614 }
2615
2616 kernel_wait_quiescent(kernel_tracer_fd);
2617 break;
2618 }
2619 case LTTNG_DOMAIN_UST:
2620 {
2621 struct lttng_channel *attr;
2622 struct ltt_ust_channel *uchan;
2623
2624 /* Get channel from global UST domain */
2625 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2626 channel_name);
2627 if (uchan == NULL) {
2628 /* Create default channel */
2629 attr = channel_new_default_attr(domain);
2630 if (attr == NULL) {
2631 ret = LTTCOMM_FATAL;
2632 goto error;
2633 }
2634 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2635 attr->name[NAME_MAX - 1] = '\0';
2636
2637 ret = channel_ust_create(usess, domain, attr);
2638 if (ret != LTTCOMM_OK) {
2639 free(attr);
2640 goto error;
2641 }
2642 free(attr);
2643
2644 /* Get the newly created channel reference back */
2645 uchan = trace_ust_find_channel_by_name(
2646 usess->domain_global.channels, channel_name);
2647 if (uchan == NULL) {
2648 /* Something is really wrong */
2649 ret = LTTCOMM_FATAL;
2650 goto error;
2651 }
2652 }
2653
2654 /* At this point, the session and channel exist on the tracer */
2655 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2656 if (ret != LTTCOMM_OK) {
2657 goto error;
2658 }
2659 break;
2660 }
2661#if 0
2662 case LTTNG_DOMAIN_UST_EXEC_NAME:
2663 case LTTNG_DOMAIN_UST_PID:
2664 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2665#endif
2666 default:
2667 ret = LTTCOMM_UND;
2668 goto error;
2669 }
2670
2671 ret = LTTCOMM_OK;
2672
2673error:
2674 return ret;
2675}
2676
2677/*
2678 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2679 */
2680static int cmd_enable_event_all(struct ltt_session *session, int domain,
2681 char *channel_name, int event_type)
2682{
2683 int ret;
2684 struct ltt_kernel_channel *kchan;
2685
2686 switch (domain) {
2687 case LTTNG_DOMAIN_KERNEL:
2688 kchan = trace_kernel_get_channel_by_name(channel_name,
2689 session->kernel_session);
2690 if (kchan == NULL) {
2691 /* This call will notify the kernel thread */
2692 ret = channel_kernel_create(session->kernel_session, NULL,
2693 kernel_poll_pipe[1]);
2694 if (ret != LTTCOMM_OK) {
2695 goto error;
2696 }
2697
2698 /* Get the newly created kernel channel pointer */
2699 kchan = trace_kernel_get_channel_by_name(channel_name,
2700 session->kernel_session);
2701 if (kchan == NULL) {
2702 /* This sould not happen... */
2703 ret = LTTCOMM_FATAL;
2704 goto error;
2705 }
2706
2707 }
2708
2709 switch (event_type) {
2710 case LTTNG_EVENT_SYSCALL:
2711 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2712 kchan, kernel_tracer_fd);
2713 break;
2714 case LTTNG_EVENT_TRACEPOINT:
2715 /*
2716 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2717 * events already registered to the channel.
2718 */
2719 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2720 kchan, kernel_tracer_fd);
2721 break;
2722 case LTTNG_EVENT_ALL:
2723 /* Enable syscalls and tracepoints */
2724 ret = event_kernel_enable_all(session->kernel_session,
2725 kchan, kernel_tracer_fd);
2726 break;
2727 default:
2728 ret = LTTCOMM_KERN_ENABLE_FAIL;
2729 goto error;
2730 }
2731
2732 /* Manage return value */
2733 if (ret != LTTCOMM_OK) {
2734 goto error;
2735 }
2736
2737 kernel_wait_quiescent(kernel_tracer_fd);
2738 break;
2739 case LTTNG_DOMAIN_UST:
2740 {
2741 struct lttng_channel *attr;
2742 struct ltt_ust_channel *uchan;
2743 struct ltt_ust_session *usess = session->ust_session;
2744
2745 /* Get channel from global UST domain */
2746 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2747 channel_name);
2748 if (uchan == NULL) {
2749 /* Create default channel */
2750 attr = channel_new_default_attr(domain);
2751 if (attr == NULL) {
2752 ret = LTTCOMM_FATAL;
2753 goto error;
2754 }
2755 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2756 attr->name[NAME_MAX - 1] = '\0';
2757
2758 /* Use the internal command enable channel */
2759 ret = channel_ust_create(usess, domain, attr);
2760 if (ret != LTTCOMM_OK) {
2761 free(attr);
2762 goto error;
2763 }
2764 free(attr);
2765
2766 /* Get the newly created channel reference back */
2767 uchan = trace_ust_find_channel_by_name(
2768 usess->domain_global.channels, channel_name);
2769 if (uchan == NULL) {
2770 /* Something is really wrong */
2771 ret = LTTCOMM_FATAL;
2772 goto error;
2773 }
2774 }
2775
2776 /* At this point, the session and channel exist on the tracer */
2777
2778 switch (event_type) {
2779 case LTTNG_EVENT_ALL:
2780 case LTTNG_EVENT_TRACEPOINT:
2781 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2782 if (ret != LTTCOMM_OK) {
2783 goto error;
2784 }
2785 break;
2786 default:
2787 ret = LTTCOMM_UST_ENABLE_FAIL;
2788 goto error;
2789 }
2790
2791 /* Manage return value */
2792 if (ret != LTTCOMM_OK) {
2793 goto error;
2794 }
2795
2796 break;
2797 }
2798#if 0
2799 case LTTNG_DOMAIN_UST_EXEC_NAME:
2800 case LTTNG_DOMAIN_UST_PID:
2801 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2802#endif
2803 default:
2804 ret = LTTCOMM_UND;
2805 goto error;
2806 }
2807
2808 ret = LTTCOMM_OK;
2809
2810error:
2811 return ret;
2812}
2813
2814/*
2815 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2816 */
2817static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2818{
2819 int ret;
2820 ssize_t nb_events = 0;
2821
2822 switch (domain) {
2823 case LTTNG_DOMAIN_KERNEL:
2824 nb_events = kernel_list_events(kernel_tracer_fd, events);
2825 if (nb_events < 0) {
2826 ret = LTTCOMM_KERN_LIST_FAIL;
2827 goto error;
2828 }
2829 break;
2830 case LTTNG_DOMAIN_UST:
2831 nb_events = ust_app_list_events(events);
2832 if (nb_events < 0) {
2833 ret = LTTCOMM_UST_LIST_FAIL;
2834 goto error;
2835 }
2836 break;
2837 default:
2838 ret = LTTCOMM_UND;
2839 goto error;
2840 }
2841
2842 return nb_events;
2843
2844error:
2845 /* Return negative value to differentiate return code */
2846 return -ret;
2847}
2848
2849/*
2850 * Command LTTNG_START_TRACE processed by the client thread.
2851 */
2852static int cmd_start_trace(struct ltt_session *session)
2853{
2854 int ret;
2855 struct ltt_kernel_session *ksession;
2856 struct ltt_ust_session *usess;
2857
2858 /* Short cut */
2859 ksession = session->kernel_session;
2860 usess = session->ust_session;
2861
2862 if (session->enabled) {
2863 /* Already started. */
2864 ret = LTTCOMM_TRACE_ALREADY_STARTED;
2865 goto error;
2866 }
2867
2868 session->enabled = 1;
2869
2870 /* Kernel tracing */
2871 if (ksession != NULL) {
2872 struct ltt_kernel_channel *kchan;
2873
2874 /* Open kernel metadata */
2875 if (ksession->metadata == NULL) {
2876 ret = kernel_open_metadata(ksession, ksession->trace_path);
2877 if (ret < 0) {
2878 ret = LTTCOMM_KERN_META_FAIL;
2879 goto error;
2880 }
2881 }
2882
2883 /* Open kernel metadata stream */
2884 if (ksession->metadata_stream_fd < 0) {
2885 ret = kernel_open_metadata_stream(ksession);
2886 if (ret < 0) {
2887 ERR("Kernel create metadata stream failed");
2888 ret = LTTCOMM_KERN_STREAM_FAIL;
2889 goto error;
2890 }
2891 }
2892
2893 /* For each channel */
2894 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2895 if (kchan->stream_count == 0) {
2896 ret = kernel_open_channel_stream(kchan);
2897 if (ret < 0) {
2898 ret = LTTCOMM_KERN_STREAM_FAIL;
2899 goto error;
2900 }
2901 /* Update the stream global counter */
2902 ksession->stream_count_global += ret;
2903 }
2904 }
2905
2906 /* Setup kernel consumer socket and send fds to it */
2907 ret = init_kernel_tracing(ksession);
2908 if (ret < 0) {
2909 ret = LTTCOMM_KERN_START_FAIL;
2910 goto error;
2911 }
2912
2913 /* This start the kernel tracing */
2914 ret = kernel_start_session(ksession);
2915 if (ret < 0) {
2916 ret = LTTCOMM_KERN_START_FAIL;
2917 goto error;
2918 }
2919
2920 /* Quiescent wait after starting trace */
2921 kernel_wait_quiescent(kernel_tracer_fd);
2922 }
2923
2924 /* Flag session that trace should start automatically */
2925 if (usess) {
2926 usess->start_trace = 1;
2927
2928 ret = ust_app_start_trace_all(usess);
2929 if (ret < 0) {
2930 ret = LTTCOMM_UST_START_FAIL;
2931 goto error;
2932 }
2933 }
2934
2935 ret = LTTCOMM_OK;
2936
2937error:
2938 return ret;
2939}
2940
2941/*
2942 * Command LTTNG_STOP_TRACE processed by the client thread.
2943 */
2944static int cmd_stop_trace(struct ltt_session *session)
2945{
2946 int ret;
2947 struct ltt_kernel_channel *kchan;
2948 struct ltt_kernel_session *ksession;
2949 struct ltt_ust_session *usess;
2950
2951 /* Short cut */
2952 ksession = session->kernel_session;
2953 usess = session->ust_session;
2954
2955 if (!session->enabled) {
2956 ret = LTTCOMM_TRACE_ALREADY_STOPPED;
2957 goto error;
2958 }
2959
2960 session->enabled = 0;
2961
2962 /* Kernel tracer */
2963 if (ksession != NULL) {
2964 DBG("Stop kernel tracing");
2965
2966 /* Flush all buffers before stopping */
2967 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2968 if (ret < 0) {
2969 ERR("Kernel metadata flush failed");
2970 }
2971
2972 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2973 ret = kernel_flush_buffer(kchan);
2974 if (ret < 0) {
2975 ERR("Kernel flush buffer error");
2976 }
2977 }
2978
2979 ret = kernel_stop_session(ksession);
2980 if (ret < 0) {
2981 ret = LTTCOMM_KERN_STOP_FAIL;
2982 goto error;
2983 }
2984
2985 kernel_wait_quiescent(kernel_tracer_fd);
2986 }
2987
2988 if (usess) {
2989 usess->start_trace = 0;
2990
2991 ret = ust_app_stop_trace_all(usess);
2992 if (ret < 0) {
2993 ret = LTTCOMM_UST_STOP_FAIL;
2994 goto error;
2995 }
2996 }
2997
2998 ret = LTTCOMM_OK;
2999
3000error:
3001 return ret;
3002}
3003
3004/*
3005 * Command LTTNG_CREATE_SESSION processed by the client thread.
3006 */
3007static int cmd_create_session(char *name, char *path, lttng_sock_cred *creds)
3008{
3009 int ret;
3010
3011 ret = session_create(name, path, LTTNG_SOCK_GET_UID_CRED(creds),
3012 LTTNG_SOCK_GET_GID_CRED(creds));
3013 if (ret != LTTCOMM_OK) {
3014 goto error;
3015 }
3016
3017 ret = LTTCOMM_OK;
3018
3019error:
3020 return ret;
3021}
3022
3023/*
3024 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3025 */
3026static int cmd_destroy_session(struct ltt_session *session, char *name)
3027{
3028 int ret;
3029
3030 /* Clean kernel session teardown */
3031 teardown_kernel_session(session);
3032 /* UST session teardown */
3033 teardown_ust_session(session);
3034
3035 /*
3036 * Must notify the kernel thread here to update it's poll setin order
3037 * to remove the channel(s)' fd just destroyed.
3038 */
3039 ret = notify_thread_pipe(kernel_poll_pipe[1]);
3040 if (ret < 0) {
3041 PERROR("write kernel poll pipe");
3042 }
3043
3044 ret = session_destroy(session);
3045
3046 return ret;
3047}
3048
3049/*
3050 * Command LTTNG_CALIBRATE processed by the client thread.
3051 */
3052static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3053{
3054 int ret;
3055
3056 switch (domain) {
3057 case LTTNG_DOMAIN_KERNEL:
3058 {
3059 struct lttng_kernel_calibrate kcalibrate;
3060
3061 kcalibrate.type = calibrate->type;
3062 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3063 if (ret < 0) {
3064 ret = LTTCOMM_KERN_ENABLE_FAIL;
3065 goto error;
3066 }
3067 break;
3068 }
3069 case LTTNG_DOMAIN_UST:
3070 {
3071 struct lttng_ust_calibrate ucalibrate;
3072
3073 ucalibrate.type = calibrate->type;
3074 ret = ust_app_calibrate_glb(&ucalibrate);
3075 if (ret < 0) {
3076 ret = LTTCOMM_UST_CALIBRATE_FAIL;
3077 goto error;
3078 }
3079 break;
3080 }
3081 default:
3082 ret = LTTCOMM_UND;
3083 goto error;
3084 }
3085
3086 ret = LTTCOMM_OK;
3087
3088error:
3089 return ret;
3090}
3091
3092/*
3093 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3094 */
3095static int cmd_register_consumer(struct ltt_session *session, int domain,
3096 char *sock_path)
3097{
3098 int ret, sock;
3099
3100 switch (domain) {
3101 case LTTNG_DOMAIN_KERNEL:
3102 /* Can't register a consumer if there is already one */
3103 if (session->kernel_session->consumer_fds_sent != 0) {
3104 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3105 goto error;
3106 }
3107
3108 sock = lttcomm_connect_unix_sock(sock_path);
3109 if (sock < 0) {
3110 ret = LTTCOMM_CONNECT_FAIL;
3111 goto error;
3112 }
3113
3114 session->kernel_session->consumer_fd = sock;
3115 break;
3116 default:
3117 /* TODO: Userspace tracing */
3118 ret = LTTCOMM_UND;
3119 goto error;
3120 }
3121
3122 ret = LTTCOMM_OK;
3123
3124error:
3125 return ret;
3126}
3127
3128/*
3129 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3130 */
3131static ssize_t cmd_list_domains(struct ltt_session *session,
3132 struct lttng_domain **domains)
3133{
3134 int ret, index = 0;
3135 ssize_t nb_dom = 0;
3136
3137 if (session->kernel_session != NULL) {
3138 DBG3("Listing domains found kernel domain");
3139 nb_dom++;
3140 }
3141
3142 if (session->ust_session != NULL) {
3143 DBG3("Listing domains found UST global domain");
3144 nb_dom++;
3145 }
3146
3147 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3148 if (*domains == NULL) {
3149 ret = -LTTCOMM_FATAL;
3150 goto error;
3151 }
3152
3153 if (session->kernel_session != NULL) {
3154 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3155 index++;
3156 }
3157
3158 if (session->ust_session != NULL) {
3159 (*domains)[index].type = LTTNG_DOMAIN_UST;
3160 index++;
3161 }
3162
3163 return nb_dom;
3164
3165error:
3166 return ret;
3167}
3168
3169/*
3170 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3171 */
3172static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3173 struct lttng_channel **channels)
3174{
3175 int ret;
3176 ssize_t nb_chan = 0;
3177
3178 switch (domain) {
3179 case LTTNG_DOMAIN_KERNEL:
3180 if (session->kernel_session != NULL) {
3181 nb_chan = session->kernel_session->channel_count;
3182 }
3183 DBG3("Number of kernel channels %zd", nb_chan);
3184 break;
3185 case LTTNG_DOMAIN_UST:
3186 if (session->ust_session != NULL) {
3187 nb_chan = lttng_ht_get_count(
3188 session->ust_session->domain_global.channels);
3189 }
3190 DBG3("Number of UST global channels %zd", nb_chan);
3191 break;
3192 default:
3193 *channels = NULL;
3194 ret = -LTTCOMM_UND;
3195 goto error;
3196 }
3197
3198 if (nb_chan > 0) {
3199 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3200 if (*channels == NULL) {
3201 ret = -LTTCOMM_FATAL;
3202 goto error;
3203 }
3204
3205 list_lttng_channels(domain, session, *channels);
3206 } else {
3207 *channels = NULL;
3208 }
3209
3210 return nb_chan;
3211
3212error:
3213 return ret;
3214}
3215
3216/*
3217 * Command LTTNG_LIST_EVENTS processed by the client thread.
3218 */
3219static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3220 char *channel_name, struct lttng_event **events)
3221{
3222 int ret = 0;
3223 ssize_t nb_event = 0;
3224
3225 switch (domain) {
3226 case LTTNG_DOMAIN_KERNEL:
3227 if (session->kernel_session != NULL) {
3228 nb_event = list_lttng_kernel_events(channel_name,
3229 session->kernel_session, events);
3230 }
3231 break;
3232 case LTTNG_DOMAIN_UST:
3233 {
3234 if (session->ust_session != NULL) {
3235 nb_event = list_lttng_ust_global_events(channel_name,
3236 &session->ust_session->domain_global, events);
3237 }
3238 break;
3239 }
3240 default:
3241 ret = -LTTCOMM_UND;
3242 goto error;
3243 }
3244
3245 ret = nb_event;
3246
3247error:
3248 return ret;
3249}
3250
3251/*
3252 * Process the command requested by the lttng client within the command
3253 * context structure. This function make sure that the return structure (llm)
3254 * is set and ready for transmission before returning.
3255 *
3256 * Return any error encountered or 0 for success.
3257 */
3258static int process_client_msg(struct command_ctx *cmd_ctx)
3259{
3260 int ret = LTTCOMM_OK;
3261 int need_tracing_session = 1;
3262 int need_domain;
3263
3264 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3265
3266 switch (cmd_ctx->lsm->cmd_type) {
3267 case LTTNG_CREATE_SESSION:
3268 case LTTNG_DESTROY_SESSION:
3269 case LTTNG_LIST_SESSIONS:
3270 case LTTNG_LIST_DOMAINS:
3271 case LTTNG_START_TRACE:
3272 case LTTNG_STOP_TRACE:
3273 need_domain = 0;
3274 break;
3275 default:
3276 need_domain = 1;
3277 }
3278
3279 if (opt_no_kernel && need_domain
3280 && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
3281 if (!is_root) {
3282 ret = LTTCOMM_NEED_ROOT_SESSIOND;
3283 } else {
3284 ret = LTTCOMM_KERN_NA;
3285 }
3286 goto error;
3287 }
3288
3289 /*
3290 * Check for command that don't needs to allocate a returned payload. We do
3291 * this here so we don't have to make the call for no payload at each
3292 * command.
3293 */
3294 switch(cmd_ctx->lsm->cmd_type) {
3295 case LTTNG_LIST_SESSIONS:
3296 case LTTNG_LIST_TRACEPOINTS:
3297 case LTTNG_LIST_DOMAINS:
3298 case LTTNG_LIST_CHANNELS:
3299 case LTTNG_LIST_EVENTS:
3300 break;
3301 default:
3302 /* Setup lttng message with no payload */
3303 ret = setup_lttng_msg(cmd_ctx, 0);
3304 if (ret < 0) {
3305 /* This label does not try to unlock the session */
3306 goto init_setup_error;
3307 }
3308 }
3309
3310 /* Commands that DO NOT need a session. */
3311 switch (cmd_ctx->lsm->cmd_type) {
3312 case LTTNG_CREATE_SESSION:
3313 case LTTNG_CALIBRATE:
3314 case LTTNG_LIST_SESSIONS:
3315 case LTTNG_LIST_TRACEPOINTS:
3316 need_tracing_session = 0;
3317 break;
3318 default:
3319 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3320 /*
3321 * We keep the session list lock across _all_ commands
3322 * for now, because the per-session lock does not
3323 * handle teardown properly.
3324 */
3325 session_lock_list();
3326 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3327 if (cmd_ctx->session == NULL) {
3328 if (cmd_ctx->lsm->session.name != NULL) {
3329 ret = LTTCOMM_SESS_NOT_FOUND;
3330 } else {
3331 /* If no session name specified */
3332 ret = LTTCOMM_SELECT_SESS;
3333 }
3334 goto error;
3335 } else {
3336 /* Acquire lock for the session */
3337 session_lock(cmd_ctx->session);
3338 }
3339 break;
3340 }
3341
3342 if (!need_domain) {
3343 goto skip_domain;
3344 }
3345 /*
3346 * Check domain type for specific "pre-action".
3347 */
3348 switch (cmd_ctx->lsm->domain.type) {
3349 case LTTNG_DOMAIN_KERNEL:
3350 if (!is_root) {
3351 ret = LTTCOMM_NEED_ROOT_SESSIOND;
3352 goto error;
3353 }
3354
3355 /* Kernel tracer check */
3356 if (kernel_tracer_fd == -1) {
3357 /* Basically, load kernel tracer modules */
3358 ret = init_kernel_tracer();
3359 if (ret != 0) {
3360 goto error;
3361 }
3362 }
3363
3364 /* Need a session for kernel command */
3365 if (need_tracing_session) {
3366 if (cmd_ctx->session->kernel_session == NULL) {
3367 ret = create_kernel_session(cmd_ctx->session);
3368 if (ret < 0) {
3369 ret = LTTCOMM_KERN_SESS_FAIL;
3370 goto error;
3371 }
3372 }
3373
3374 /* Start the kernel consumer daemon */
3375 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3376 if (kconsumer_data.pid == 0 &&
3377 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3378 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3379 ret = start_consumerd(&kconsumer_data);
3380 if (ret < 0) {
3381 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3382 goto error;
3383 }
3384 } else {
3385 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3386 }
3387 }
3388 break;
3389 case LTTNG_DOMAIN_UST:
3390 {
3391 if (need_tracing_session) {
3392 if (cmd_ctx->session->ust_session == NULL) {
3393 ret = create_ust_session(cmd_ctx->session,
3394 &cmd_ctx->lsm->domain);
3395 if (ret != LTTCOMM_OK) {
3396 goto error;
3397 }
3398 }
3399 /* Start the UST consumer daemons */
3400 /* 64-bit */
3401 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3402 if (consumerd64_bin[0] != '\0' &&
3403 ustconsumer64_data.pid == 0 &&
3404 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3405 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3406 ret = start_consumerd(&ustconsumer64_data);
3407 if (ret < 0) {
3408 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3409 ust_consumerd64_fd = -EINVAL;
3410 goto error;
3411 }
3412
3413 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3414 } else {
3415 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3416 }
3417 /* 32-bit */
3418 if (consumerd32_bin[0] != '\0' &&
3419 ustconsumer32_data.pid == 0 &&
3420 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3421 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3422 ret = start_consumerd(&ustconsumer32_data);
3423 if (ret < 0) {
3424 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3425 ust_consumerd32_fd = -EINVAL;
3426 goto error;
3427 }
3428 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3429 } else {
3430 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3431 }
3432 }
3433 break;
3434 }
3435 default:
3436 break;
3437 }
3438skip_domain:
3439
3440 /*
3441 * Check that the UID or GID match that of the tracing session.
3442 * The root user can interact with all sessions.
3443 */
3444 if (need_tracing_session) {
3445 if (!session_access_ok(cmd_ctx->session,
3446 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
3447 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds))) {
3448 ret = LTTCOMM_EPERM;
3449 goto error;
3450 }
3451 }
3452
3453 /* Process by command type */
3454 switch (cmd_ctx->lsm->cmd_type) {
3455 case LTTNG_ADD_CONTEXT:
3456 {
3457 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3458 cmd_ctx->lsm->u.context.channel_name,
3459 cmd_ctx->lsm->u.context.event_name,
3460 &cmd_ctx->lsm->u.context.ctx);
3461 break;
3462 }
3463 case LTTNG_DISABLE_CHANNEL:
3464 {
3465 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3466 cmd_ctx->lsm->u.disable.channel_name);
3467 break;
3468 }
3469 case LTTNG_DISABLE_EVENT:
3470 {
3471 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3472 cmd_ctx->lsm->u.disable.channel_name,
3473 cmd_ctx->lsm->u.disable.name);
3474 break;
3475 }
3476 case LTTNG_DISABLE_ALL_EVENT:
3477 {
3478 DBG("Disabling all events");
3479
3480 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3481 cmd_ctx->lsm->u.disable.channel_name);
3482 break;
3483 }
3484 case LTTNG_ENABLE_CHANNEL:
3485 {
3486 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3487 &cmd_ctx->lsm->u.channel.chan);
3488 break;
3489 }
3490 case LTTNG_ENABLE_EVENT:
3491 {
3492 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3493 cmd_ctx->lsm->u.enable.channel_name,
3494 &cmd_ctx->lsm->u.enable.event);
3495 break;
3496 }
3497 case LTTNG_ENABLE_ALL_EVENT:
3498 {
3499 DBG("Enabling all events");
3500
3501 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3502 cmd_ctx->lsm->u.enable.channel_name,
3503 cmd_ctx->lsm->u.enable.event.type);
3504 break;
3505 }
3506 case LTTNG_LIST_TRACEPOINTS:
3507 {
3508 struct lttng_event *events;
3509 ssize_t nb_events;
3510
3511 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3512 if (nb_events < 0) {
3513 ret = -nb_events;
3514 goto error;
3515 }
3516
3517 /*
3518 * Setup lttng message with payload size set to the event list size in
3519 * bytes and then copy list into the llm payload.
3520 */
3521 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3522 if (ret < 0) {
3523 free(events);
3524 goto setup_error;
3525 }
3526
3527 /* Copy event list into message payload */
3528 memcpy(cmd_ctx->llm->payload, events,
3529 sizeof(struct lttng_event) * nb_events);
3530
3531 free(events);
3532
3533 ret = LTTCOMM_OK;
3534 break;
3535 }
3536 case LTTNG_START_TRACE:
3537 {
3538 ret = cmd_start_trace(cmd_ctx->session);
3539 break;
3540 }
3541 case LTTNG_STOP_TRACE:
3542 {
3543 ret = cmd_stop_trace(cmd_ctx->session);
3544 break;
3545 }
3546 case LTTNG_CREATE_SESSION:
3547 {
3548 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3549 cmd_ctx->lsm->session.path, &cmd_ctx->creds);
3550 break;
3551 }
3552 case LTTNG_DESTROY_SESSION:
3553 {
3554 ret = cmd_destroy_session(cmd_ctx->session,
3555 cmd_ctx->lsm->session.name);
3556 /*
3557 * Set session to NULL so we do not unlock it after
3558 * free.
3559 */
3560 cmd_ctx->session = NULL;
3561 break;
3562 }
3563 case LTTNG_LIST_DOMAINS:
3564 {
3565 ssize_t nb_dom;
3566 struct lttng_domain *domains;
3567
3568 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3569 if (nb_dom < 0) {
3570 ret = -nb_dom;
3571 goto error;
3572 }
3573
3574 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3575 if (ret < 0) {
3576 goto setup_error;
3577 }
3578
3579 /* Copy event list into message payload */
3580 memcpy(cmd_ctx->llm->payload, domains,
3581 nb_dom * sizeof(struct lttng_domain));
3582
3583 free(domains);
3584
3585 ret = LTTCOMM_OK;
3586 break;
3587 }
3588 case LTTNG_LIST_CHANNELS:
3589 {
3590 size_t nb_chan;
3591 struct lttng_channel *channels;
3592
3593 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
3594 cmd_ctx->session, &channels);
3595 if (nb_chan < 0) {
3596 ret = -nb_chan;
3597 goto error;
3598 }
3599
3600 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3601 if (ret < 0) {
3602 goto setup_error;
3603 }
3604
3605 /* Copy event list into message payload */
3606 memcpy(cmd_ctx->llm->payload, channels,
3607 nb_chan * sizeof(struct lttng_channel));
3608
3609 free(channels);
3610
3611 ret = LTTCOMM_OK;
3612 break;
3613 }
3614 case LTTNG_LIST_EVENTS:
3615 {
3616 ssize_t nb_event;
3617 struct lttng_event *events = NULL;
3618
3619 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
3620 cmd_ctx->lsm->u.list.channel_name, &events);
3621 if (nb_event < 0) {
3622 ret = -nb_event;
3623 goto error;
3624 }
3625
3626 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3627 if (ret < 0) {
3628 goto setup_error;
3629 }
3630
3631 /* Copy event list into message payload */
3632 memcpy(cmd_ctx->llm->payload, events,
3633 nb_event * sizeof(struct lttng_event));
3634
3635 free(events);
3636
3637 ret = LTTCOMM_OK;
3638 break;
3639 }
3640 case LTTNG_LIST_SESSIONS:
3641 {
3642 unsigned int nr_sessions;
3643
3644 session_lock_list();
3645 nr_sessions = lttng_sessions_count(
3646 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
3647 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
3648
3649 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * nr_sessions);
3650 if (ret < 0) {
3651 session_unlock_list();
3652 goto setup_error;
3653 }
3654
3655 /* Filled the session array */
3656 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload),
3657 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
3658 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
3659
3660 session_unlock_list();
3661
3662 ret = LTTCOMM_OK;
3663 break;
3664 }
3665 case LTTNG_CALIBRATE:
3666 {
3667 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3668 &cmd_ctx->lsm->u.calibrate);
3669 break;
3670 }
3671 case LTTNG_REGISTER_CONSUMER:
3672 {
3673 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3674 cmd_ctx->lsm->u.reg.path);
3675 break;
3676 }
3677 default:
3678 ret = LTTCOMM_UND;
3679 break;
3680 }
3681
3682error:
3683 if (cmd_ctx->llm == NULL) {
3684 DBG("Missing llm structure. Allocating one.");
3685 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3686 goto setup_error;
3687 }
3688 }
3689 /* Set return code */
3690 cmd_ctx->llm->ret_code = ret;
3691setup_error:
3692 if (cmd_ctx->session) {
3693 session_unlock(cmd_ctx->session);
3694 }
3695 if (need_tracing_session) {
3696 session_unlock_list();
3697 }
3698init_setup_error:
3699 return ret;
3700}
3701
3702/*
3703 * This thread manage all clients request using the unix client socket for
3704 * communication.
3705 */
3706static void *thread_manage_clients(void *data)
3707{
3708 int sock = -1, ret, i, pollfd;
3709 uint32_t revents, nb_fd;
3710 struct command_ctx *cmd_ctx = NULL;
3711 struct lttng_poll_event events;
3712
3713 DBG("[thread] Manage client started");
3714
3715 rcu_register_thread();
3716
3717 ret = lttcomm_listen_unix_sock(client_sock);
3718 if (ret < 0) {
3719 goto error;
3720 }
3721
3722 /*
3723 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3724 * more will be added to this poll set.
3725 */
3726 ret = create_thread_poll_set(&events, 2);
3727 if (ret < 0) {
3728 goto error;
3729 }
3730
3731 /* Add the application registration socket */
3732 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3733 if (ret < 0) {
3734 goto error;
3735 }
3736
3737 /*
3738 * Notify parent pid that we are ready to accept command for client side.
3739 */
3740 if (opt_sig_parent) {
3741 kill(ppid, SIGUSR1);
3742 }
3743
3744 while (1) {
3745 DBG("Accepting client command ...");
3746
3747 nb_fd = LTTNG_POLL_GETNB(&events);
3748
3749 /* Inifinite blocking call, waiting for transmission */
3750 restart:
3751 ret = lttng_poll_wait(&events, -1);
3752 if (ret < 0) {
3753 /*
3754 * Restart interrupted system call.
3755 */
3756 if (errno == EINTR) {
3757 goto restart;
3758 }
3759 goto error;
3760 }
3761
3762 for (i = 0; i < nb_fd; i++) {
3763 /* Fetch once the poll data */
3764 revents = LTTNG_POLL_GETEV(&events, i);
3765 pollfd = LTTNG_POLL_GETFD(&events, i);
3766
3767 /* Thread quit pipe has been closed. Killing thread. */
3768 ret = check_thread_quit_pipe(pollfd, revents);
3769 if (ret) {
3770 goto error;
3771 }
3772
3773 /* Event on the registration socket */
3774 if (pollfd == client_sock) {
3775 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3776 ERR("Client socket poll error");
3777 goto error;
3778 }
3779 }
3780 }
3781
3782 DBG("Wait for client response");
3783
3784 sock = lttcomm_accept_unix_sock(client_sock);
3785 if (sock < 0) {
3786 goto error;
3787 }
3788
3789 /* Set socket option for credentials retrieval */
3790 ret = lttcomm_setsockopt_creds_unix_sock(sock);
3791 if (ret < 0) {
3792 goto error;
3793 }
3794
3795 /* Allocate context command to process the client request */
3796 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3797 if (cmd_ctx == NULL) {
3798 PERROR("zmalloc cmd_ctx");
3799 goto error;
3800 }
3801
3802 /* Allocate data buffer for reception */
3803 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3804 if (cmd_ctx->lsm == NULL) {
3805 PERROR("zmalloc cmd_ctx->lsm");
3806 goto error;
3807 }
3808
3809 cmd_ctx->llm = NULL;
3810 cmd_ctx->session = NULL;
3811
3812 /*
3813 * Data is received from the lttng client. The struct
3814 * lttcomm_session_msg (lsm) contains the command and data request of
3815 * the client.
3816 */
3817 DBG("Receiving data from client ...");
3818 ret = lttcomm_recv_creds_unix_sock(sock, cmd_ctx->lsm,
3819 sizeof(struct lttcomm_session_msg), &cmd_ctx->creds);
3820 if (ret <= 0) {
3821 DBG("Nothing recv() from client... continuing");
3822 ret = close(sock);
3823 if (ret) {
3824 PERROR("close");
3825 }
3826 sock = -1;
3827 clean_command_ctx(&cmd_ctx);
3828 continue;
3829 }
3830
3831 // TODO: Validate cmd_ctx including sanity check for
3832 // security purpose.
3833
3834 rcu_thread_online();
3835 /*
3836 * This function dispatch the work to the kernel or userspace tracer
3837 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3838 * informations for the client. The command context struct contains
3839 * everything this function may needs.
3840 */
3841 ret = process_client_msg(cmd_ctx);
3842 rcu_thread_offline();
3843 if (ret < 0) {
3844 /*
3845 * TODO: Inform client somehow of the fatal error. At
3846 * this point, ret < 0 means that a zmalloc failed
3847 * (ENOMEM). Error detected but still accept command.
3848 */
3849 clean_command_ctx(&cmd_ctx);
3850 continue;
3851 }
3852
3853 DBG("Sending response (size: %d, retcode: %s)",
3854 cmd_ctx->lttng_msg_size,
3855 lttng_strerror(-cmd_ctx->llm->ret_code));
3856 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3857 if (ret < 0) {
3858 ERR("Failed to send data back to client");
3859 }
3860
3861 /* End of transmission */
3862 ret = close(sock);
3863 if (ret) {
3864 PERROR("close");
3865 }
3866 sock = -1;
3867
3868 clean_command_ctx(&cmd_ctx);
3869 }
3870
3871error:
3872 DBG("Client thread dying");
3873 unlink(client_unix_sock_path);
3874 if (client_sock >= 0) {
3875 ret = close(client_sock);
3876 if (ret) {
3877 PERROR("close");
3878 }
3879 }
3880 if (sock >= 0) {
3881 ret = close(sock);
3882 if (ret) {
3883 PERROR("close");
3884 }
3885 }
3886
3887 lttng_poll_clean(&events);
3888 clean_command_ctx(&cmd_ctx);
3889
3890 rcu_unregister_thread();
3891 return NULL;
3892}
3893
3894
3895/*
3896 * usage function on stderr
3897 */
3898static void usage(void)
3899{
3900 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3901 fprintf(stderr, " -h, --help Display this usage.\n");
3902 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3903 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3904 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3905 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3906 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
3907 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
3908 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
3909 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
3910 fprintf(stderr, " --consumerd32-path PATH Specify path for the 32-bit UST consumer daemon binary\n");
3911 fprintf(stderr, " --consumerd32-libdir PATH Specify path for the 32-bit UST consumer daemon libraries\n");
3912 fprintf(stderr, " --consumerd64-path PATH Specify path for the 64-bit UST consumer daemon binary\n");
3913 fprintf(stderr, " --consumerd64-libdir PATH Specify path for the 64-bit UST consumer daemon libraries\n");
3914 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3915 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3916 fprintf(stderr, " -V, --version Show version number.\n");
3917 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3918 fprintf(stderr, " -q, --quiet No output at all.\n");
3919 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3920 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3921 fprintf(stderr, " --no-kernel Disable kernel tracer\n");
3922}
3923
3924/*
3925 * daemon argument parsing
3926 */
3927static int parse_args(int argc, char **argv)
3928{
3929 int c;
3930
3931 static struct option long_options[] = {
3932 { "client-sock", 1, 0, 'c' },
3933 { "apps-sock", 1, 0, 'a' },
3934 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3935 { "kconsumerd-err-sock", 1, 0, 'E' },
3936 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
3937 { "ustconsumerd32-err-sock", 1, 0, 'H' },
3938 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
3939 { "ustconsumerd64-err-sock", 1, 0, 'F' },
3940 { "consumerd32-path", 1, 0, 'u' },
3941 { "consumerd32-libdir", 1, 0, 'U' },
3942 { "consumerd64-path", 1, 0, 't' },
3943 { "consumerd64-libdir", 1, 0, 'T' },
3944 { "daemonize", 0, 0, 'd' },
3945 { "sig-parent", 0, 0, 'S' },
3946 { "help", 0, 0, 'h' },
3947 { "group", 1, 0, 'g' },
3948 { "version", 0, 0, 'V' },
3949 { "quiet", 0, 0, 'q' },
3950 { "verbose", 0, 0, 'v' },
3951 { "verbose-consumer", 0, 0, 'Z' },
3952 { "no-kernel", 0, 0, 'N' },
3953 { NULL, 0, 0, 0 }
3954 };
3955
3956 while (1) {
3957 int option_index = 0;
3958 c = getopt_long(argc, argv, "dhqvVSN" "a:c:g:s:C:E:D:F:Z:u:t",
3959 long_options, &option_index);
3960 if (c == -1) {
3961 break;
3962 }
3963
3964 switch (c) {
3965 case 0:
3966 fprintf(stderr, "option %s", long_options[option_index].name);
3967 if (optarg) {
3968 fprintf(stderr, " with arg %s\n", optarg);
3969 }
3970 break;
3971 case 'c':
3972 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3973 break;
3974 case 'a':
3975 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3976 break;
3977 case 'd':
3978 opt_daemon = 1;
3979 break;
3980 case 'g':
3981 opt_tracing_group = optarg;
3982 break;
3983 case 'h':
3984 usage();
3985 exit(EXIT_FAILURE);
3986 case 'V':
3987 fprintf(stdout, "%s\n", VERSION);
3988 exit(EXIT_SUCCESS);
3989 case 'S':
3990 opt_sig_parent = 1;
3991 break;
3992 case 'E':
3993 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3994 break;
3995 case 'C':
3996 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3997 break;
3998 case 'F':
3999 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
4000 break;
4001 case 'D':
4002 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
4003 break;
4004 case 'H':
4005 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
4006 break;
4007 case 'G':
4008 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
4009 break;
4010 case 'N':
4011 opt_no_kernel = 1;
4012 break;
4013 case 'q':
4014 lttng_opt_quiet = 1;
4015 break;
4016 case 'v':
4017 /* Verbose level can increase using multiple -v */
4018 lttng_opt_verbose += 1;
4019 break;
4020 case 'Z':
4021 opt_verbose_consumer += 1;
4022 break;
4023 case 'u':
4024 consumerd32_bin= optarg;
4025 break;
4026 case 'U':
4027 consumerd32_libdir = optarg;
4028 break;
4029 case 't':
4030 consumerd64_bin = optarg;
4031 break;
4032 case 'T':
4033 consumerd64_libdir = optarg;
4034 break;
4035 default:
4036 /* Unknown option or other error.
4037 * Error is printed by getopt, just return */
4038 return -1;
4039 }
4040 }
4041
4042 return 0;
4043}
4044
4045/*
4046 * Creates the two needed socket by the daemon.
4047 * apps_sock - The communication socket for all UST apps.
4048 * client_sock - The communication of the cli tool (lttng).
4049 */
4050static int init_daemon_socket(void)
4051{
4052 int ret = 0;
4053 mode_t old_umask;
4054
4055 old_umask = umask(0);
4056
4057 /* Create client tool unix socket */
4058 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
4059 if (client_sock < 0) {
4060 ERR("Create unix sock failed: %s", client_unix_sock_path);
4061 ret = -1;
4062 goto end;
4063 }
4064
4065 /* File permission MUST be 660 */
4066 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
4067 if (ret < 0) {
4068 ERR("Set file permissions failed: %s", client_unix_sock_path);
4069 PERROR("chmod");
4070 goto end;
4071 }
4072
4073 /* Create the application unix socket */
4074 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
4075 if (apps_sock < 0) {
4076 ERR("Create unix sock failed: %s", apps_unix_sock_path);
4077 ret = -1;
4078 goto end;
4079 }
4080
4081 /* File permission MUST be 666 */
4082 ret = chmod(apps_unix_sock_path,
4083 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
4084 if (ret < 0) {
4085 ERR("Set file permissions failed: %s", apps_unix_sock_path);
4086 PERROR("chmod");
4087 goto end;
4088 }
4089
4090end:
4091 umask(old_umask);
4092 return ret;
4093}
4094
4095/*
4096 * Check if the global socket is available, and if a daemon is answering at the
4097 * other side. If yes, error is returned.
4098 */
4099static int check_existing_daemon(void)
4100{
4101 /* Is there anybody out there ? */
4102 if (lttng_session_daemon_alive()) {
4103 return -EEXIST;
4104 }
4105
4106 return 0;
4107}
4108
4109/*
4110 * Set the tracing group gid onto the client socket.
4111 *
4112 * Race window between mkdir and chown is OK because we are going from more
4113 * permissive (root.root) to less permissive (root.tracing).
4114 */
4115static int set_permissions(char *rundir)
4116{
4117 int ret;
4118 gid_t gid;
4119
4120 gid = allowed_group();
4121 if (gid < 0) {
4122 WARN("No tracing group detected");
4123 ret = 0;
4124 goto end;
4125 }
4126
4127 /* Set lttng run dir */
4128 ret = chown(rundir, 0, gid);
4129 if (ret < 0) {
4130 ERR("Unable to set group on %s", rundir);
4131 PERROR("chown");
4132 }
4133
4134 /* Ensure tracing group can search the run dir */
4135 ret = chmod(rundir, S_IRWXU | S_IXGRP | S_IXOTH);
4136 if (ret < 0) {
4137 ERR("Unable to set permissions on %s", rundir);
4138 PERROR("chmod");
4139 }
4140
4141 /* lttng client socket path */
4142 ret = chown(client_unix_sock_path, 0, gid);
4143 if (ret < 0) {
4144 ERR("Unable to set group on %s", client_unix_sock_path);
4145 PERROR("chown");
4146 }
4147
4148 /* kconsumer error socket path */
4149 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
4150 if (ret < 0) {
4151 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
4152 PERROR("chown");
4153 }
4154
4155 /* 64-bit ustconsumer error socket path */
4156 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
4157 if (ret < 0) {
4158 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
4159 PERROR("chown");
4160 }
4161
4162 /* 32-bit ustconsumer compat32 error socket path */
4163 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
4164 if (ret < 0) {
4165 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
4166 PERROR("chown");
4167 }
4168
4169 DBG("All permissions are set");
4170
4171end:
4172 return ret;
4173}
4174
4175/*
4176 * Create the pipe used to wake up the kernel thread.
4177 * Closed in cleanup().
4178 */
4179static int create_kernel_poll_pipe(void)
4180{
4181 int ret, i;
4182
4183 ret = pipe(kernel_poll_pipe);
4184 if (ret < 0) {
4185 PERROR("kernel poll pipe");
4186 goto error;
4187 }
4188
4189 for (i = 0; i < 2; i++) {
4190 ret = fcntl(kernel_poll_pipe[i], F_SETFD, FD_CLOEXEC);
4191 if (ret < 0) {
4192 PERROR("fcntl kernel_poll_pipe");
4193 goto error;
4194 }
4195 }
4196
4197error:
4198 return ret;
4199}
4200
4201/*
4202 * Create the application command pipe to wake thread_manage_apps.
4203 * Closed in cleanup().
4204 */
4205static int create_apps_cmd_pipe(void)
4206{
4207 int ret, i;
4208
4209 ret = pipe(apps_cmd_pipe);
4210 if (ret < 0) {
4211 PERROR("apps cmd pipe");
4212 goto error;
4213 }
4214
4215 for (i = 0; i < 2; i++) {
4216 ret = fcntl(apps_cmd_pipe[i], F_SETFD, FD_CLOEXEC);
4217 if (ret < 0) {
4218 PERROR("fcntl apps_cmd_pipe");
4219 goto error;
4220 }
4221 }
4222
4223error:
4224 return ret;
4225}
4226
4227/*
4228 * Create the lttng run directory needed for all global sockets and pipe.
4229 */
4230static int create_lttng_rundir(const char *rundir)
4231{
4232 int ret;
4233
4234 DBG3("Creating LTTng run directory: %s", rundir);
4235
4236 ret = mkdir(rundir, S_IRWXU);
4237 if (ret < 0) {
4238 if (errno != EEXIST) {
4239 ERR("Unable to create %s", rundir);
4240 goto error;
4241 } else {
4242 ret = 0;
4243 }
4244 }
4245
4246error:
4247 return ret;
4248}
4249
4250/*
4251 * Setup sockets and directory needed by the kconsumerd communication with the
4252 * session daemon.
4253 */
4254static int set_consumer_sockets(struct consumer_data *consumer_data,
4255 const char *rundir)
4256{
4257 int ret;
4258 char path[PATH_MAX];
4259
4260 switch (consumer_data->type) {
4261 case LTTNG_CONSUMER_KERNEL:
4262 snprintf(path, PATH_MAX, DEFAULT_KCONSUMERD_PATH, rundir);
4263 break;
4264 case LTTNG_CONSUMER64_UST:
4265 snprintf(path, PATH_MAX, DEFAULT_USTCONSUMERD64_PATH, rundir);
4266 break;
4267 case LTTNG_CONSUMER32_UST:
4268 snprintf(path, PATH_MAX, DEFAULT_USTCONSUMERD32_PATH, rundir);
4269 break;
4270 default:
4271 ERR("Consumer type unknown");
4272 ret = -EINVAL;
4273 goto error;
4274 }
4275
4276 DBG2("Creating consumer directory: %s", path);
4277
4278 ret = mkdir(path, S_IRWXU);
4279 if (ret < 0) {
4280 if (errno != EEXIST) {
4281 PERROR("mkdir");
4282 ERR("Failed to create %s", path);
4283 goto error;
4284 }
4285 ret = -1;
4286 }
4287
4288 /* Create the kconsumerd error unix socket */
4289 consumer_data->err_sock =
4290 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
4291 if (consumer_data->err_sock < 0) {
4292 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
4293 ret = -1;
4294 goto error;
4295 }
4296
4297 /* File permission MUST be 660 */
4298 ret = chmod(consumer_data->err_unix_sock_path,
4299 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
4300 if (ret < 0) {
4301 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
4302 PERROR("chmod");
4303 goto error;
4304 }
4305
4306error:
4307 return ret;
4308}
4309
4310/*
4311 * Signal handler for the daemon
4312 *
4313 * Simply stop all worker threads, leaving main() return gracefully after
4314 * joining all threads and calling cleanup().
4315 */
4316static void sighandler(int sig)
4317{
4318 switch (sig) {
4319 case SIGPIPE:
4320 DBG("SIGPIPE caught");
4321 return;
4322 case SIGINT:
4323 DBG("SIGINT caught");
4324 stop_threads();
4325 break;
4326 case SIGTERM:
4327 DBG("SIGTERM caught");
4328 stop_threads();
4329 break;
4330 default:
4331 break;
4332 }
4333}
4334
4335/*
4336 * Setup signal handler for :
4337 * SIGINT, SIGTERM, SIGPIPE
4338 */
4339static int set_signal_handler(void)
4340{
4341 int ret = 0;
4342 struct sigaction sa;
4343 sigset_t sigset;
4344
4345 if ((ret = sigemptyset(&sigset)) < 0) {
4346 PERROR("sigemptyset");
4347 return ret;
4348 }
4349
4350 sa.sa_handler = sighandler;
4351 sa.sa_mask = sigset;
4352 sa.sa_flags = 0;
4353 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
4354 PERROR("sigaction");
4355 return ret;
4356 }
4357
4358 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
4359 PERROR("sigaction");
4360 return ret;
4361 }
4362
4363 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
4364 PERROR("sigaction");
4365 return ret;
4366 }
4367
4368 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
4369
4370 return ret;
4371}
4372
4373/*
4374 * Set open files limit to unlimited. This daemon can open a large number of
4375 * file descriptors in order to consumer multiple kernel traces.
4376 */
4377static void set_ulimit(void)
4378{
4379 int ret;
4380 struct rlimit lim;
4381
4382 /* The kernel does not allowed an infinite limit for open files */
4383 lim.rlim_cur = 65535;
4384 lim.rlim_max = 65535;
4385
4386 ret = setrlimit(RLIMIT_NOFILE, &lim);
4387 if (ret < 0) {
4388 PERROR("failed to set open files limit");
4389 }
4390}
4391
4392/*
4393 * main
4394 */
4395int main(int argc, char **argv)
4396{
4397 int ret = 0;
4398 void *status;
4399 const char *home_path;
4400
4401 init_kernel_workarounds();
4402
4403 rcu_register_thread();
4404
4405 /* Create thread quit pipe */
4406 if ((ret = init_thread_quit_pipe()) < 0) {
4407 goto error;
4408 }
4409
4410 setup_consumerd_path();
4411
4412 /* Parse arguments */
4413 progname = argv[0];
4414 if ((ret = parse_args(argc, argv) < 0)) {
4415 goto error;
4416 }
4417
4418 /* Daemonize */
4419 if (opt_daemon) {
4420 ret = daemon(0, 0);
4421 if (ret < 0) {
4422 PERROR("daemon");
4423 goto error;
4424 }
4425 }
4426
4427 /* Check if daemon is UID = 0 */
4428 is_root = !getuid();
4429
4430 if (is_root) {
4431 rundir = strdup(DEFAULT_LTTNG_RUNDIR);
4432
4433 /* Create global run dir with root access */
4434 ret = create_lttng_rundir(rundir);
4435 if (ret < 0) {
4436 goto error;
4437 }
4438
4439 if (strlen(apps_unix_sock_path) == 0) {
4440 snprintf(apps_unix_sock_path, PATH_MAX,
4441 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
4442 }
4443
4444 if (strlen(client_unix_sock_path) == 0) {
4445 snprintf(client_unix_sock_path, PATH_MAX,
4446 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
4447 }
4448
4449 /* Set global SHM for ust */
4450 if (strlen(wait_shm_path) == 0) {
4451 snprintf(wait_shm_path, PATH_MAX,
4452 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
4453 }
4454
4455 /* Setup kernel consumerd path */
4456 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX,
4457 DEFAULT_KCONSUMERD_ERR_SOCK_PATH, rundir);
4458 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX,
4459 DEFAULT_KCONSUMERD_CMD_SOCK_PATH, rundir);
4460
4461 DBG2("Kernel consumer err path: %s",
4462 kconsumer_data.err_unix_sock_path);
4463 DBG2("Kernel consumer cmd path: %s",
4464 kconsumer_data.cmd_unix_sock_path);
4465 } else {
4466 home_path = get_home_dir();
4467 if (home_path == NULL) {
4468 /* TODO: Add --socket PATH option */
4469 ERR("Can't get HOME directory for sockets creation.");
4470 ret = -EPERM;
4471 goto error;
4472 }
4473
4474 /*
4475 * Create rundir from home path. This will create something like
4476 * $HOME/.lttng
4477 */
4478 ret = asprintf(&rundir, DEFAULT_LTTNG_HOME_RUNDIR, home_path);
4479 if (ret < 0) {
4480 ret = -ENOMEM;
4481 goto error;
4482 }
4483
4484 ret = create_lttng_rundir(rundir);
4485 if (ret < 0) {
4486 goto error;
4487 }
4488
4489 if (strlen(apps_unix_sock_path) == 0) {
4490 snprintf(apps_unix_sock_path, PATH_MAX,
4491 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
4492 }
4493
4494 /* Set the cli tool unix socket path */
4495 if (strlen(client_unix_sock_path) == 0) {
4496 snprintf(client_unix_sock_path, PATH_MAX,
4497 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
4498 }
4499
4500 /* Set global SHM for ust */
4501 if (strlen(wait_shm_path) == 0) {
4502 snprintf(wait_shm_path, PATH_MAX,
4503 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
4504 }
4505 }
4506
4507 DBG("Client socket path %s", client_unix_sock_path);
4508 DBG("Application socket path %s", apps_unix_sock_path);
4509 DBG("LTTng run directory path: %s", rundir);
4510
4511 /* 32 bits consumerd path setup */
4512 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX,
4513 DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH, rundir);
4514 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX,
4515 DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH, rundir);
4516
4517 DBG2("UST consumer 32 bits err path: %s",
4518 ustconsumer32_data.err_unix_sock_path);
4519 DBG2("UST consumer 32 bits cmd path: %s",
4520 ustconsumer32_data.cmd_unix_sock_path);
4521
4522 /* 64 bits consumerd path setup */
4523 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX,
4524 DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH, rundir);
4525 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX,
4526 DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH, rundir);
4527
4528 DBG2("UST consumer 64 bits err path: %s",
4529 ustconsumer64_data.err_unix_sock_path);
4530 DBG2("UST consumer 64 bits cmd path: %s",
4531 ustconsumer64_data.cmd_unix_sock_path);
4532
4533 /*
4534 * See if daemon already exist.
4535 */
4536 if ((ret = check_existing_daemon()) < 0) {
4537 ERR("Already running daemon.\n");
4538 /*
4539 * We do not goto exit because we must not cleanup()
4540 * because a daemon is already running.
4541 */
4542 goto error;
4543 }
4544
4545 /*
4546 * Init UST app hash table. Alloc hash table before this point since
4547 * cleanup() can get called after that point.
4548 */
4549 ust_app_ht_alloc();
4550
4551 /* After this point, we can safely call cleanup() with "goto exit" */
4552
4553 /*
4554 * These actions must be executed as root. We do that *after* setting up
4555 * the sockets path because we MUST make the check for another daemon using
4556 * those paths *before* trying to set the kernel consumer sockets and init
4557 * kernel tracer.
4558 */
4559 if (is_root) {
4560 ret = set_consumer_sockets(&kconsumer_data, rundir);
4561 if (ret < 0) {
4562 goto exit;
4563 }
4564
4565 /* Setup kernel tracer */
4566 if (!opt_no_kernel) {
4567 init_kernel_tracer();
4568 }
4569
4570 /* Set ulimit for open files */
4571 set_ulimit();
4572 }
4573 /* init lttng_fd tracking must be done after set_ulimit. */
4574 lttng_fd_init();
4575
4576 ret = set_consumer_sockets(&ustconsumer64_data, rundir);
4577 if (ret < 0) {
4578 goto exit;
4579 }
4580
4581 ret = set_consumer_sockets(&ustconsumer32_data, rundir);
4582 if (ret < 0) {
4583 goto exit;
4584 }
4585
4586 if ((ret = set_signal_handler()) < 0) {
4587 goto exit;
4588 }
4589
4590 /* Setup the needed unix socket */
4591 if ((ret = init_daemon_socket()) < 0) {
4592 goto exit;
4593 }
4594
4595 /* Set credentials to socket */
4596 if (is_root && ((ret = set_permissions(rundir)) < 0)) {
4597 goto exit;
4598 }
4599
4600 /* Get parent pid if -S, --sig-parent is specified. */
4601 if (opt_sig_parent) {
4602 ppid = getppid();
4603 }
4604
4605 /* Setup the kernel pipe for waking up the kernel thread */
4606 if ((ret = create_kernel_poll_pipe()) < 0) {
4607 goto exit;
4608 }
4609
4610 /* Setup the thread apps communication pipe. */
4611 if ((ret = create_apps_cmd_pipe()) < 0) {
4612 goto exit;
4613 }
4614
4615 /* Init UST command queue. */
4616 cds_wfq_init(&ust_cmd_queue.queue);
4617
4618 /*
4619 * Get session list pointer. This pointer MUST NOT be free(). This list is
4620 * statically declared in session.c
4621 */
4622 session_list_ptr = session_get_list();
4623
4624 /* Set up max poll set size */
4625 lttng_poll_set_max_size();
4626
4627 /* Create thread to manage the client socket */
4628 ret = pthread_create(&client_thread, NULL,
4629 thread_manage_clients, (void *) NULL);
4630 if (ret != 0) {
4631 PERROR("pthread_create clients");
4632 goto exit_client;
4633 }
4634
4635 /* Create thread to dispatch registration */
4636 ret = pthread_create(&dispatch_thread, NULL,
4637 thread_dispatch_ust_registration, (void *) NULL);
4638 if (ret != 0) {
4639 PERROR("pthread_create dispatch");
4640 goto exit_dispatch;
4641 }
4642
4643 /* Create thread to manage application registration. */
4644 ret = pthread_create(&reg_apps_thread, NULL,
4645 thread_registration_apps, (void *) NULL);
4646 if (ret != 0) {
4647 PERROR("pthread_create registration");
4648 goto exit_reg_apps;
4649 }
4650
4651 /* Create thread to manage application socket */
4652 ret = pthread_create(&apps_thread, NULL,
4653 thread_manage_apps, (void *) NULL);
4654 if (ret != 0) {
4655 PERROR("pthread_create apps");
4656 goto exit_apps;
4657 }
4658
4659 /* Create kernel thread to manage kernel event */
4660 ret = pthread_create(&kernel_thread, NULL,
4661 thread_manage_kernel, (void *) NULL);
4662 if (ret != 0) {
4663 PERROR("pthread_create kernel");
4664 goto exit_kernel;
4665 }
4666
4667 ret = pthread_join(kernel_thread, &status);
4668 if (ret != 0) {
4669 PERROR("pthread_join");
4670 goto error; /* join error, exit without cleanup */
4671 }
4672
4673exit_kernel:
4674 ret = pthread_join(apps_thread, &status);
4675 if (ret != 0) {
4676 PERROR("pthread_join");
4677 goto error; /* join error, exit without cleanup */
4678 }
4679
4680exit_apps:
4681 ret = pthread_join(reg_apps_thread, &status);
4682 if (ret != 0) {
4683 PERROR("pthread_join");
4684 goto error; /* join error, exit without cleanup */
4685 }
4686
4687exit_reg_apps:
4688 ret = pthread_join(dispatch_thread, &status);
4689 if (ret != 0) {
4690 PERROR("pthread_join");
4691 goto error; /* join error, exit without cleanup */
4692 }
4693
4694exit_dispatch:
4695 ret = pthread_join(client_thread, &status);
4696 if (ret != 0) {
4697 PERROR("pthread_join");
4698 goto error; /* join error, exit without cleanup */
4699 }
4700
4701 ret = join_consumer_thread(&kconsumer_data);
4702 if (ret != 0) {
4703 PERROR("join_consumer");
4704 goto error; /* join error, exit without cleanup */
4705 }
4706
4707exit_client:
4708exit:
4709 /*
4710 * cleanup() is called when no other thread is running.
4711 */
4712 rcu_thread_online();
4713 cleanup();
4714 rcu_thread_offline();
4715 rcu_unregister_thread();
4716 if (!ret) {
4717 exit(EXIT_SUCCESS);
4718 }
4719error:
4720 exit(EXIT_FAILURE);
4721}
This page took 0.039339 seconds and 4 git commands to generate.