2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the Free
7 * Software Foundation; only version 2 of the License.
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
16 * Place - Suite 330, Boston, MA 02111-1307, USA.
25 #include <semaphore.h>
31 #include <sys/mount.h>
32 #include <sys/resource.h>
33 #include <sys/socket.h>
35 #include <sys/types.h>
37 #include <urcu/futex.h>
40 #include <ltt-kconsumerd.h>
41 #include <lttng-sessiond-comm.h>
42 #include <lttng/lttng-kconsumerd.h>
46 #include "compat/poll.h"
50 #include "kernel-ctl.h"
51 #include "ltt-sessiond.h"
53 #include "traceable-app.h"
58 #include "benchmark.h"
61 const char default_home_dir
[] = DEFAULT_HOME_DIR
;
62 const char default_tracing_group
[] = LTTNG_DEFAULT_TRACING_GROUP
;
63 const char default_ust_sock_dir
[] = DEFAULT_UST_SOCK_DIR
;
64 const char default_global_apps_pipe
[] = DEFAULT_GLOBAL_APPS_PIPE
;
67 int opt_verbose
; /* Not static for lttngerr.h */
68 int opt_verbose_kconsumerd
; /* Not static for lttngerr.h */
69 int opt_quiet
; /* Not static for lttngerr.h */
72 const char *opt_tracing_group
;
73 static int opt_sig_parent
;
74 static int opt_daemon
;
75 static int is_root
; /* Set to 1 if the daemon is running as root */
76 static pid_t ppid
; /* Parent PID for --sig-parent option */
77 static pid_t kconsumerd_pid
;
78 static int dispatch_thread_exit
;
80 /* Global application Unix socket path */
81 static char apps_unix_sock_path
[PATH_MAX
];
82 /* Global client Unix socket path */
83 static char client_unix_sock_path
[PATH_MAX
];
84 /* kconsumerd error and command Unix socket path */
85 static char kconsumerd_err_unix_sock_path
[PATH_MAX
];
86 static char kconsumerd_cmd_unix_sock_path
[PATH_MAX
];
87 /* global wait shm path for UST */
88 static char wait_shm_path
[PATH_MAX
];
91 static int client_sock
;
93 static int kconsumerd_err_sock
;
94 static int kconsumerd_cmd_sock
;
95 static int kernel_tracer_fd
;
96 static int kernel_poll_pipe
[2];
99 * Quit pipe for all threads. This permits a single cancellation point
100 * for all threads when receiving an event on the pipe.
102 static int thread_quit_pipe
[2];
105 * This pipe is used to inform the thread managing application communication
106 * that a command is queued and ready to be processed.
108 static int apps_cmd_pipe
[2];
110 /* Pthread, Mutexes and Semaphores */
111 static pthread_t kconsumerd_thread
;
112 static pthread_t apps_thread
;
113 static pthread_t reg_apps_thread
;
114 static pthread_t client_thread
;
115 static pthread_t kernel_thread
;
116 static pthread_t dispatch_thread
;
117 static sem_t kconsumerd_sem
;
120 /* Mutex to control kconsumerd pid assignation */
121 static pthread_mutex_t kconsumerd_pid_mutex
;
124 * UST registration command queue. This queue is tied with a futex and uses a N
125 * wakers / 1 waiter implemented and detailed in futex.c/.h
127 * The thread_manage_apps and thread_dispatch_ust_registration interact with
128 * this queue and the wait/wake scheme.
130 static struct ust_cmd_queue ust_cmd_queue
;
133 * Pointer initialized before thread creation.
135 * This points to the tracing session list containing the session count and a
136 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
137 * MUST NOT be taken if you call a public function in session.c.
139 * The lock is nested inside the structure: session_list_ptr->lock. Please use
140 * session_lock_list and session_unlock_list for lock acquisition.
142 static struct ltt_session_list
*session_list_ptr
;
145 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
147 static int create_thread_poll_set(struct lttng_poll_event
*events
,
152 if (events
== NULL
|| size
== 0) {
157 ret
= lttng_poll_create(events
, size
, LTTNG_CLOEXEC
);
163 ret
= lttng_poll_add(events
, thread_quit_pipe
[0], LPOLLIN
);
175 * Check if the thread quit pipe was triggered.
177 * Return 1 if it was triggered else 0;
179 static int check_thread_quit_pipe(int fd
, uint32_t events
)
181 if (fd
== thread_quit_pipe
[0] && (events
& LPOLLIN
)) {
189 * Remove modules in reverse load order.
191 static int modprobe_remove_kernel_modules(void)
196 for (i
= ARRAY_SIZE(kernel_modules_list
) - 1; i
>= 0; i
--) {
197 ret
= snprintf(modprobe
, sizeof(modprobe
),
198 "/sbin/modprobe --remove --quiet %s",
199 kernel_modules_list
[i
].name
);
201 perror("snprintf modprobe --remove");
204 modprobe
[sizeof(modprobe
) - 1] = '\0';
205 ret
= system(modprobe
);
207 ERR("Unable to launch modprobe --remove for module %s",
208 kernel_modules_list
[i
].name
);
209 } else if (kernel_modules_list
[i
].required
210 && WEXITSTATUS(ret
) != 0) {
211 ERR("Unable to remove module %s",
212 kernel_modules_list
[i
].name
);
214 DBG("Modprobe removal successful %s",
215 kernel_modules_list
[i
].name
);
224 * Return group ID of the tracing group or -1 if not found.
226 static gid_t
allowed_group(void)
230 if (opt_tracing_group
) {
231 grp
= getgrnam(opt_tracing_group
);
233 grp
= getgrnam(default_tracing_group
);
243 * Init thread quit pipe.
245 * Return -1 on error or 0 if all pipes are created.
247 static int init_thread_quit_pipe(void)
251 ret
= pipe2(thread_quit_pipe
, O_CLOEXEC
);
253 perror("thread quit pipe");
262 * Complete teardown of a kernel session. This free all data structure related
263 * to a kernel session and update counter.
265 static void teardown_kernel_session(struct ltt_session
*session
)
267 if (session
->kernel_session
!= NULL
) {
268 DBG("Tearing down kernel session");
271 * If a custom kernel consumer was registered, close the socket before
272 * tearing down the complete kernel session structure
274 if (session
->kernel_session
->consumer_fd
!= kconsumerd_cmd_sock
) {
275 lttcomm_close_unix_sock(session
->kernel_session
->consumer_fd
);
278 trace_kernel_destroy_session(session
->kernel_session
);
279 /* Extra precaution */
280 session
->kernel_session
= NULL
;
285 * Stop all threads by closing the thread quit pipe.
287 static void stop_threads(void)
291 /* Stopping all threads */
292 DBG("Terminating all threads");
293 ret
= notify_thread_pipe(thread_quit_pipe
[1]);
295 ERR("write error on thread quit pipe");
298 /* Dispatch thread */
299 dispatch_thread_exit
= 1;
300 futex_nto1_wake(&ust_cmd_queue
.futex
);
306 static void cleanup(void)
310 struct ltt_session
*sess
, *stmp
;
315 MSG("%c[%d;%dm*** assert failed *** ==> %c[%dm%c[%d;%dm"
316 "Matthew, BEET driven development works!%c[%dm",
317 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
321 DBG("Removing %s directory", LTTNG_RUNDIR
);
322 ret
= asprintf(&cmd
, "rm -rf " LTTNG_RUNDIR
);
324 ERR("asprintf failed. Something is really wrong!");
327 /* Remove lttng run directory */
330 ERR("Unable to clean " LTTNG_RUNDIR
);
334 DBG("Cleaning up all session");
336 /* Destroy session list mutex */
337 if (session_list_ptr
!= NULL
) {
338 pthread_mutex_destroy(&session_list_ptr
->lock
);
340 /* Cleanup ALL session */
341 cds_list_for_each_entry_safe(sess
, stmp
,
342 &session_list_ptr
->head
, list
) {
343 teardown_kernel_session(sess
);
344 // TODO complete session cleanup (including UST)
348 DBG("Closing all UST sockets");
349 clean_traceable_apps_list();
351 pthread_mutex_destroy(&kconsumerd_pid_mutex
);
353 DBG("Closing kernel fd");
354 close(kernel_tracer_fd
);
357 DBG("Unloading kernel modules");
358 modprobe_remove_kernel_modules();
361 close(thread_quit_pipe
[0]);
362 close(thread_quit_pipe
[1]);
364 /* OUTPUT BENCHMARK RESULTS */
367 if (getenv("BENCH_UST_NOTIFY")) {
368 bench_print_ust_notification();
371 if (getenv("BENCH_UST_REGISTER")) {
372 bench_print_ust_register();
375 if (getenv("BENCH_BOOT_PROCESS")) {
376 bench_print_boot_process();
384 * Send data on a unix socket using the liblttsessiondcomm API.
386 * Return lttcomm error code.
388 static int send_unix_sock(int sock
, void *buf
, size_t len
)
390 /* Check valid length */
395 return lttcomm_send_unix_sock(sock
, buf
, len
);
399 * Free memory of a command context structure.
401 static void clean_command_ctx(struct command_ctx
**cmd_ctx
)
403 DBG("Clean command context structure");
405 if ((*cmd_ctx
)->llm
) {
406 free((*cmd_ctx
)->llm
);
408 if ((*cmd_ctx
)->lsm
) {
409 free((*cmd_ctx
)->lsm
);
417 * Send all stream fds of kernel channel to the consumer.
419 static int send_kconsumerd_channel_fds(int sock
,
420 struct ltt_kernel_channel
*channel
)
424 struct ltt_kernel_stream
*stream
;
425 struct lttcomm_kconsumerd_header lkh
;
426 struct lttcomm_kconsumerd_msg lkm
;
428 DBG("Sending fds of channel %s to kernel consumer",
429 channel
->channel
->name
);
431 nb_fd
= channel
->stream_count
;
434 lkh
.payload_size
= nb_fd
* sizeof(struct lttcomm_kconsumerd_msg
);
435 lkh
.cmd_type
= ADD_STREAM
;
437 DBG("Sending kconsumerd header");
439 ret
= lttcomm_send_unix_sock(sock
, &lkh
,
440 sizeof(struct lttcomm_kconsumerd_header
));
442 perror("send kconsumerd header");
446 cds_list_for_each_entry(stream
, &channel
->stream_list
.head
, list
) {
447 if (stream
->fd
!= 0) {
449 lkm
.state
= stream
->state
;
450 lkm
.max_sb_size
= channel
->channel
->attr
.subbuf_size
;
451 lkm
.output
= channel
->channel
->attr
.output
;
452 strncpy(lkm
.path_name
, stream
->pathname
, PATH_MAX
);
453 lkm
.path_name
[PATH_MAX
- 1] = '\0';
455 DBG("Sending fd %d to kconsumerd", lkm
.fd
);
457 ret
= lttcomm_send_fds_unix_sock(sock
, &lkm
,
458 &lkm
.fd
, 1, sizeof(lkm
));
460 perror("send kconsumerd fd");
466 DBG("Kconsumerd channel fds sent");
475 * Send all stream fds of the kernel session to the consumer.
477 static int send_kconsumerd_fds(struct ltt_kernel_session
*session
)
480 struct ltt_kernel_channel
*chan
;
481 struct lttcomm_kconsumerd_header lkh
;
482 struct lttcomm_kconsumerd_msg lkm
;
485 lkh
.payload_size
= sizeof(struct lttcomm_kconsumerd_msg
);
486 lkh
.cmd_type
= ADD_STREAM
;
488 DBG("Sending kconsumerd header for metadata");
490 ret
= lttcomm_send_unix_sock(session
->consumer_fd
, &lkh
,
491 sizeof(struct lttcomm_kconsumerd_header
));
493 perror("send kconsumerd header");
497 DBG("Sending metadata stream fd");
499 /* Extra protection. It's NOT suppose to be set to 0 at this point */
500 if (session
->consumer_fd
== 0) {
501 session
->consumer_fd
= kconsumerd_cmd_sock
;
504 if (session
->metadata_stream_fd
!= 0) {
505 /* Send metadata stream fd first */
506 lkm
.fd
= session
->metadata_stream_fd
;
507 lkm
.state
= ACTIVE_FD
;
508 lkm
.max_sb_size
= session
->metadata
->conf
->attr
.subbuf_size
;
509 lkm
.output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
510 strncpy(lkm
.path_name
, session
->metadata
->pathname
, PATH_MAX
);
511 lkm
.path_name
[PATH_MAX
- 1] = '\0';
513 ret
= lttcomm_send_fds_unix_sock(session
->consumer_fd
, &lkm
,
514 &lkm
.fd
, 1, sizeof(lkm
));
516 perror("send kconsumerd fd");
521 cds_list_for_each_entry(chan
, &session
->channel_list
.head
, list
) {
522 ret
= send_kconsumerd_channel_fds(session
->consumer_fd
, chan
);
528 DBG("Kconsumerd fds (metadata and channel streams) sent");
537 * Notify UST applications using the shm mmap futex.
539 static int notify_ust_apps(int active
)
543 DBG("Notifying applications of session daemon state: %d", active
);
545 tracepoint(ust_notify_apps_start
);
547 /* See shm.c for this call implying mmap, shm and futex calls */
548 wait_shm_mmap
= shm_ust_get_mmap(wait_shm_path
, is_root
);
549 if (wait_shm_mmap
== NULL
) {
553 /* Wake waiting process */
554 futex_wait_update((int32_t *) wait_shm_mmap
, active
);
556 tracepoint(ust_notify_apps_stop
);
558 /* Apps notified successfully */
566 * Setup the outgoing data buffer for the response (llm) by allocating the
567 * right amount of memory and copying the original information from the lsm
570 * Return total size of the buffer pointed by buf.
572 static int setup_lttng_msg(struct command_ctx
*cmd_ctx
, size_t size
)
578 cmd_ctx
->llm
= malloc(sizeof(struct lttcomm_lttng_msg
) + buf_size
);
579 if (cmd_ctx
->llm
== NULL
) {
585 /* Copy common data */
586 cmd_ctx
->llm
->cmd_type
= cmd_ctx
->lsm
->cmd_type
;
587 cmd_ctx
->llm
->pid
= cmd_ctx
->lsm
->domain
.attr
.pid
;
589 cmd_ctx
->llm
->data_size
= size
;
590 cmd_ctx
->lttng_msg_size
= sizeof(struct lttcomm_lttng_msg
) + buf_size
;
599 * Update the kernel poll set of all channel fd available over all tracing
600 * session. Add the wakeup pipe at the end of the set.
602 static int update_kernel_poll(struct lttng_poll_event
*events
)
605 struct ltt_session
*session
;
606 struct ltt_kernel_channel
*channel
;
608 DBG("Updating kernel poll set");
611 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
612 session_lock(session
);
613 if (session
->kernel_session
== NULL
) {
614 session_unlock(session
);
618 cds_list_for_each_entry(channel
,
619 &session
->kernel_session
->channel_list
.head
, list
) {
620 /* Add channel fd to the kernel poll set */
621 ret
= lttng_poll_add(events
, channel
->fd
, LPOLLIN
| LPOLLRDNORM
);
623 session_unlock(session
);
626 DBG("Channel fd %d added to kernel set", channel
->fd
);
628 session_unlock(session
);
630 session_unlock_list();
635 session_unlock_list();
640 * Find the channel fd from 'fd' over all tracing session. When found, check
641 * for new channel stream and send those stream fds to the kernel consumer.
643 * Useful for CPU hotplug feature.
645 static int update_kernel_stream(int fd
)
648 struct ltt_session
*session
;
649 struct ltt_kernel_channel
*channel
;
651 DBG("Updating kernel streams for channel fd %d", fd
);
654 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
655 session_lock(session
);
656 if (session
->kernel_session
== NULL
) {
657 session_unlock(session
);
661 /* This is not suppose to be 0 but this is an extra security check */
662 if (session
->kernel_session
->consumer_fd
== 0) {
663 session
->kernel_session
->consumer_fd
= kconsumerd_cmd_sock
;
666 cds_list_for_each_entry(channel
,
667 &session
->kernel_session
->channel_list
.head
, list
) {
668 if (channel
->fd
== fd
) {
669 DBG("Channel found, updating kernel streams");
670 ret
= kernel_open_channel_stream(channel
);
676 * Have we already sent fds to the consumer? If yes, it means
677 * that tracing is started so it is safe to send our updated
680 if (session
->kernel_session
->kconsumer_fds_sent
== 1) {
681 ret
= send_kconsumerd_channel_fds(
682 session
->kernel_session
->consumer_fd
, channel
);
690 session_unlock(session
);
692 session_unlock_list();
696 session_unlock(session
);
697 session_unlock_list();
702 * This thread manage event coming from the kernel.
704 * Features supported in this thread:
707 static void *thread_manage_kernel(void *data
)
709 int ret
, i
, pollfd
, update_poll_flag
= 1;
710 uint32_t revents
, nb_fd
;
712 struct lttng_poll_event events
;
714 tracepoint(sessiond_th_kern_start
);
716 DBG("Thread manage kernel started");
718 ret
= create_thread_poll_set(&events
, 2);
723 ret
= lttng_poll_add(&events
, kernel_poll_pipe
[0], LPOLLIN
);
729 if (update_poll_flag
== 1) {
730 ret
= update_kernel_poll(&events
);
734 update_poll_flag
= 0;
737 nb_fd
= LTTNG_POLL_GETNB(&events
);
739 DBG("Thread kernel polling on %d fds", nb_fd
);
741 /* Zeroed the poll events */
742 lttng_poll_reset(&events
);
744 tracepoint(sessiond_th_kern_poll
);
746 /* Poll infinite value of time */
747 ret
= lttng_poll_wait(&events
, -1);
750 } else if (ret
== 0) {
751 /* Should not happen since timeout is infinite */
752 ERR("Return value of poll is 0 with an infinite timeout.\n"
753 "This should not have happened! Continuing...");
757 for (i
= 0; i
< nb_fd
; i
++) {
758 /* Fetch once the poll data */
759 revents
= LTTNG_POLL_GETEV(&events
, i
);
760 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
762 /* Thread quit pipe has been closed. Killing thread. */
763 ret
= check_thread_quit_pipe(pollfd
, revents
);
768 /* Check for data on kernel pipe */
769 if (pollfd
== kernel_poll_pipe
[0] && (revents
& LPOLLIN
)) {
770 ret
= read(kernel_poll_pipe
[0], &tmp
, 1);
771 update_poll_flag
= 1;
775 * New CPU detected by the kernel. Adding kernel stream to
776 * kernel session and updating the kernel consumer
778 if (revents
& LPOLLIN
) {
779 ret
= update_kernel_stream(pollfd
);
785 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
786 * and unregister kernel stream at this point.
794 DBG("Kernel thread dying");
795 close(kernel_poll_pipe
[0]);
796 close(kernel_poll_pipe
[1]);
798 lttng_poll_clean(&events
);
804 * This thread manage the kconsumerd error sent back to the session daemon.
806 static void *thread_manage_kconsumerd(void *data
)
808 int sock
= 0, i
, ret
, pollfd
;
809 uint32_t revents
, nb_fd
;
810 enum lttcomm_return_code code
;
811 struct lttng_poll_event events
;
813 tracepoint(sessiond_th_kcon_start
);
815 DBG("[thread] Manage kconsumerd started");
817 ret
= lttcomm_listen_unix_sock(kconsumerd_err_sock
);
823 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
824 * Nothing more will be added to this poll set.
826 ret
= create_thread_poll_set(&events
, 2);
831 ret
= lttng_poll_add(&events
, kconsumerd_err_sock
, LPOLLIN
| LPOLLRDHUP
);
836 nb_fd
= LTTNG_POLL_GETNB(&events
);
838 tracepoint(sessiond_th_kcon_poll
);
840 /* Inifinite blocking call, waiting for transmission */
841 ret
= lttng_poll_wait(&events
, -1);
846 for (i
= 0; i
< nb_fd
; i
++) {
847 /* Fetch once the poll data */
848 revents
= LTTNG_POLL_GETEV(&events
, i
);
849 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
851 /* Thread quit pipe has been closed. Killing thread. */
852 ret
= check_thread_quit_pipe(pollfd
, revents
);
857 /* Event on the registration socket */
858 if (pollfd
== kconsumerd_err_sock
) {
859 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
860 ERR("Kconsumerd err socket poll error");
866 sock
= lttcomm_accept_unix_sock(kconsumerd_err_sock
);
871 /* Getting status code from kconsumerd */
872 ret
= lttcomm_recv_unix_sock(sock
, &code
,
873 sizeof(enum lttcomm_return_code
));
878 if (code
== KCONSUMERD_COMMAND_SOCK_READY
) {
879 kconsumerd_cmd_sock
=
880 lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path
);
881 if (kconsumerd_cmd_sock
< 0) {
882 sem_post(&kconsumerd_sem
);
883 perror("kconsumerd connect");
886 /* Signal condition to tell that the kconsumerd is ready */
887 sem_post(&kconsumerd_sem
);
888 DBG("Kconsumerd command socket ready");
890 DBG("Kconsumerd error when waiting for SOCK_READY : %s",
891 lttcomm_get_readable_code(-code
));
895 /* Remove the kconsumerd error sock since we've established a connexion */
896 ret
= lttng_poll_del(&events
, kconsumerd_err_sock
);
901 ret
= lttng_poll_add(&events
, sock
, LPOLLIN
| LPOLLRDHUP
);
906 /* Update number of fd */
907 nb_fd
= LTTNG_POLL_GETNB(&events
);
909 /* Inifinite blocking call, waiting for transmission */
910 ret
= lttng_poll_wait(&events
, -1);
915 for (i
= 0; i
< nb_fd
; i
++) {
916 /* Fetch once the poll data */
917 revents
= LTTNG_POLL_GETEV(&events
, i
);
918 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
920 /* Thread quit pipe has been closed. Killing thread. */
921 ret
= check_thread_quit_pipe(pollfd
, revents
);
926 /* Event on the kconsumerd socket */
927 if (pollfd
== sock
) {
928 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
929 ERR("Kconsumerd err socket second poll error");
935 /* Wait for any kconsumerd error */
936 ret
= lttcomm_recv_unix_sock(sock
, &code
,
937 sizeof(enum lttcomm_return_code
));
939 ERR("Kconsumerd closed the command socket");
943 ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code
));
946 DBG("Kconsumerd thread dying");
947 close(kconsumerd_err_sock
);
948 close(kconsumerd_cmd_sock
);
951 unlink(kconsumerd_err_unix_sock_path
);
952 unlink(kconsumerd_cmd_unix_sock_path
);
955 lttng_poll_clean(&events
);
961 * This thread manage application communication.
963 static void *thread_manage_apps(void *data
)
966 uint32_t revents
, nb_fd
;
967 struct ust_command ust_cmd
;
968 struct lttng_poll_event events
;
970 tracepoint(sessiond_th_apps_start
);
972 DBG("[thread] Manage application started");
974 ret
= create_thread_poll_set(&events
, 2);
979 ret
= lttng_poll_add(&events
, apps_cmd_pipe
[0], LPOLLIN
| LPOLLRDHUP
);
985 /* Zeroed the events structure */
986 lttng_poll_reset(&events
);
988 nb_fd
= LTTNG_POLL_GETNB(&events
);
990 DBG("Apps thread polling on %d fds", nb_fd
);
992 tracepoint(sessiond_th_apps_poll
);
994 /* Inifinite blocking call, waiting for transmission */
995 ret
= lttng_poll_wait(&events
, -1);
1000 for (i
= 0; i
< nb_fd
; i
++) {
1001 /* Fetch once the poll data */
1002 revents
= LTTNG_POLL_GETEV(&events
, i
);
1003 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
1005 /* Thread quit pipe has been closed. Killing thread. */
1006 ret
= check_thread_quit_pipe(pollfd
, revents
);
1011 /* Inspect the apps cmd pipe */
1012 if (pollfd
== apps_cmd_pipe
[0]) {
1013 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1014 ERR("Apps command pipe error");
1016 } else if (revents
& LPOLLIN
) {
1017 tracepoint(ust_register_read_start
);
1019 ret
= read(apps_cmd_pipe
[0], &ust_cmd
, sizeof(ust_cmd
));
1020 if (ret
< 0 || ret
< sizeof(ust_cmd
)) {
1021 perror("read apps cmd pipe");
1024 tracepoint(ust_register_read_stop
);
1026 tracepoint(ust_register_add_start
);
1027 /* Register applicaton to the session daemon */
1028 ret
= register_traceable_app(&ust_cmd
.reg_msg
,
1031 /* Only critical ENOMEM error can be returned here */
1034 tracepoint(ust_register_add_stop
);
1036 tracepoint(ust_register_done_start
);
1037 ret
= ustctl_register_done(ust_cmd
.sock
);
1040 * If the registration is not possible, we simply
1041 * unregister the apps and continue
1043 unregister_traceable_app(ust_cmd
.sock
);
1046 * We just need here to monitor the close of the UST
1047 * socket and poll set monitor those by default.
1049 ret
= lttng_poll_add(&events
, ust_cmd
.sock
, 0);
1054 DBG("Apps with sock %d added to poll set",
1057 tracepoint(ust_register_done_stop
);
1062 * At this point, we know that a registered application made
1063 * the event at poll_wait.
1065 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1066 /* Removing from the poll set */
1067 ret
= lttng_poll_del(&events
, pollfd
);
1073 unregister_traceable_app(pollfd
);
1081 DBG("Application communication apps dying");
1082 close(apps_cmd_pipe
[0]);
1083 close(apps_cmd_pipe
[1]);
1085 lttng_poll_clean(&events
);
1091 * Dispatch request from the registration threads to the application
1092 * communication thread.
1094 static void *thread_dispatch_ust_registration(void *data
)
1097 struct cds_wfq_node
*node
;
1098 struct ust_command
*ust_cmd
= NULL
;
1100 tracepoint(sessiond_th_dispatch_start
);
1102 DBG("[thread] Dispatch UST command started");
1104 while (!dispatch_thread_exit
) {
1105 /* Atomically prepare the queue futex */
1106 futex_nto1_prepare(&ust_cmd_queue
.futex
);
1109 tracepoint(sessiond_th_dispatch_block
);
1111 /* Dequeue command for registration */
1112 node
= cds_wfq_dequeue_blocking(&ust_cmd_queue
.queue
);
1114 DBG("Waked up but nothing in the UST command queue");
1115 /* Continue thread execution */
1119 tracepoint(ust_dispatch_register_start
);
1121 ust_cmd
= caa_container_of(node
, struct ust_command
, node
);
1123 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1124 " gid:%d sock:%d name:%s (version %d.%d)",
1125 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1126 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1127 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1128 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1130 * Inform apps thread of the new application registration. This
1131 * call is blocking so we can be assured that the data will be read
1132 * at some point in time or wait to the end of the world :)
1134 ret
= write(apps_cmd_pipe
[1], ust_cmd
,
1135 sizeof(struct ust_command
));
1137 perror("write apps cmd pipe");
1138 if (errno
== EBADF
) {
1140 * We can't inform the application thread to process
1141 * registration. We will exit or else application
1142 * registration will not occur and tracing will never
1149 } while (node
!= NULL
);
1151 tracepoint(ust_dispatch_register_stop
);
1153 /* Futex wait on queue. Blocking call on futex() */
1154 futex_nto1_wait(&ust_cmd_queue
.futex
);
1158 DBG("Dispatch thread dying");
1163 * This thread manage application registration.
1165 static void *thread_registration_apps(void *data
)
1167 int sock
= 0, i
, ret
, pollfd
;
1168 uint32_t revents
, nb_fd
;
1169 struct lttng_poll_event events
;
1171 * Get allocated in this thread, enqueued to a global queue, dequeued and
1172 * freed in the manage apps thread.
1174 struct ust_command
*ust_cmd
= NULL
;
1176 tracepoint(sessiond_th_reg_start
);
1178 DBG("[thread] Manage application registration started");
1180 ret
= lttcomm_listen_unix_sock(apps_sock
);
1186 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1187 * more will be added to this poll set.
1189 ret
= create_thread_poll_set(&events
, 2);
1194 /* Add the application registration socket */
1195 ret
= lttng_poll_add(&events
, apps_sock
, LPOLLIN
| LPOLLRDHUP
);
1200 /* Notify all applications to register */
1201 ret
= notify_ust_apps(1);
1203 ERR("Failed to notify applications or create the wait shared memory.\n"
1204 "Execution continues but there might be problem for already\n"
1205 "running applications that wishes to register.");
1209 DBG("Accepting application registration");
1211 tracepoint(sessiond_th_reg_poll
);
1213 nb_fd
= LTTNG_POLL_GETNB(&events
);
1215 /* Inifinite blocking call, waiting for transmission */
1216 ret
= lttng_poll_wait(&events
, -1);
1221 for (i
= 0; i
< nb_fd
; i
++) {
1222 /* Fetch once the poll data */
1223 revents
= LTTNG_POLL_GETEV(&events
, i
);
1224 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
1226 /* Thread quit pipe has been closed. Killing thread. */
1227 ret
= check_thread_quit_pipe(pollfd
, revents
);
1232 /* Event on the registration socket */
1233 if (pollfd
== apps_sock
) {
1234 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1235 ERR("Register apps socket poll error");
1237 } else if (revents
& LPOLLIN
) {
1238 /* Registration starts here. Recording cycles */
1239 tracepoint(ust_register_start
);
1241 sock
= lttcomm_accept_unix_sock(apps_sock
);
1246 /* Create UST registration command for enqueuing */
1247 ust_cmd
= malloc(sizeof(struct ust_command
));
1248 if (ust_cmd
== NULL
) {
1249 perror("ust command malloc");
1254 * Using message-based transmissions to ensure we don't
1255 * have to deal with partially received messages.
1257 ret
= lttcomm_recv_unix_sock(sock
, &ust_cmd
->reg_msg
,
1258 sizeof(struct ust_register_msg
));
1259 if (ret
< 0 || ret
< sizeof(struct ust_register_msg
)) {
1261 perror("lttcomm_recv_unix_sock register apps");
1263 ERR("Wrong size received on apps register");
1270 ust_cmd
->sock
= sock
;
1272 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1273 " gid:%d sock:%d name:%s (version %d.%d)",
1274 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1275 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1276 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1277 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1280 * Lock free enqueue the registration request. The red pill
1281 * has been taken! This apps will be part of the *system*.
1283 cds_wfq_enqueue(&ust_cmd_queue
.queue
, &ust_cmd
->node
);
1286 * Wake the registration queue futex. Implicit memory
1287 * barrier with the exchange in cds_wfq_enqueue.
1289 futex_nto1_wake(&ust_cmd_queue
.futex
);
1291 tracepoint(ust_register_stop
);
1298 DBG("UST Registration thread dying");
1300 /* Notify that the registration thread is gone */
1305 unlink(apps_unix_sock_path
);
1307 lttng_poll_clean(&events
);
1313 * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
1314 * exec or it will fails.
1316 static int spawn_kconsumerd_thread(void)
1320 /* Setup semaphore */
1321 sem_init(&kconsumerd_sem
, 0, 0);
1323 ret
= pthread_create(&kconsumerd_thread
, NULL
,
1324 thread_manage_kconsumerd
, (void *) NULL
);
1326 perror("pthread_create kconsumerd");
1330 /* Wait for the kconsumerd thread to be ready */
1331 sem_wait(&kconsumerd_sem
);
1333 if (kconsumerd_pid
== 0) {
1334 ERR("Kconsumerd did not start");
1341 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1346 * Join kernel consumer thread
1348 static int join_kconsumerd_thread(void)
1353 if (kconsumerd_pid
!= 0) {
1354 ret
= kill(kconsumerd_pid
, SIGTERM
);
1356 ERR("Error killing kconsumerd");
1359 return pthread_join(kconsumerd_thread
, &status
);
1366 * Fork and exec a kernel consumer daemon (kconsumerd).
1368 * Return pid if successful else -1.
1370 static pid_t
spawn_kconsumerd(void)
1374 const char *verbosity
;
1376 DBG("Spawning kconsumerd");
1383 if (opt_verbose
> 1 || opt_verbose_kconsumerd
) {
1384 verbosity
= "--verbose";
1386 verbosity
= "--quiet";
1388 execl(INSTALL_BIN_PATH
"/ltt-kconsumerd",
1389 "ltt-kconsumerd", verbosity
, NULL
);
1391 perror("kernel start consumer exec");
1394 } else if (pid
> 0) {
1398 perror("kernel start consumer fork");
1408 * Spawn the kconsumerd daemon and session daemon thread.
1410 static int start_kconsumerd(void)
1414 pthread_mutex_lock(&kconsumerd_pid_mutex
);
1415 if (kconsumerd_pid
!= 0) {
1416 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1420 ret
= spawn_kconsumerd();
1422 ERR("Spawning kconsumerd failed");
1423 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1424 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1428 /* Setting up the global kconsumerd_pid */
1429 kconsumerd_pid
= ret
;
1430 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1432 DBG("Kconsumerd pid %d", ret
);
1434 DBG("Spawning kconsumerd thread");
1435 ret
= spawn_kconsumerd_thread();
1437 ERR("Fatal error spawning kconsumerd thread");
1449 * modprobe_kernel_modules
1451 static int modprobe_kernel_modules(void)
1456 for (i
= 0; i
< ARRAY_SIZE(kernel_modules_list
); i
++) {
1457 ret
= snprintf(modprobe
, sizeof(modprobe
),
1458 "/sbin/modprobe %s%s",
1459 kernel_modules_list
[i
].required
? "" : "--quiet ",
1460 kernel_modules_list
[i
].name
);
1462 perror("snprintf modprobe");
1465 modprobe
[sizeof(modprobe
) - 1] = '\0';
1466 ret
= system(modprobe
);
1468 ERR("Unable to launch modprobe for module %s",
1469 kernel_modules_list
[i
].name
);
1470 } else if (kernel_modules_list
[i
].required
1471 && WEXITSTATUS(ret
) != 0) {
1472 ERR("Unable to load module %s",
1473 kernel_modules_list
[i
].name
);
1475 DBG("Modprobe successfully %s",
1476 kernel_modules_list
[i
].name
);
1487 static int mount_debugfs(char *path
)
1490 char *type
= "debugfs";
1492 ret
= mkdir_recursive(path
, S_IRWXU
| S_IRWXG
, geteuid(), getegid());
1497 ret
= mount(type
, path
, type
, 0, NULL
);
1499 perror("mount debugfs");
1503 DBG("Mounted debugfs successfully at %s", path
);
1510 * Setup necessary data for kernel tracer action.
1512 static void init_kernel_tracer(void)
1515 char *proc_mounts
= "/proc/mounts";
1517 char *debugfs_path
= NULL
, *lttng_path
= NULL
;
1520 /* Detect debugfs */
1521 fp
= fopen(proc_mounts
, "r");
1523 ERR("Unable to probe %s", proc_mounts
);
1527 while (fgets(line
, sizeof(line
), fp
) != NULL
) {
1528 if (strstr(line
, "debugfs") != NULL
) {
1529 /* Remove first string */
1531 /* Dup string here so we can reuse line later on */
1532 debugfs_path
= strdup(strtok(NULL
, " "));
1533 DBG("Got debugfs path : %s", debugfs_path
);
1540 /* Mount debugfs if needded */
1541 if (debugfs_path
== NULL
) {
1542 ret
= asprintf(&debugfs_path
, "/mnt/debugfs");
1544 perror("asprintf debugfs path");
1547 ret
= mount_debugfs(debugfs_path
);
1553 /* Modprobe lttng kernel modules */
1554 ret
= modprobe_kernel_modules();
1559 /* Setup lttng kernel path */
1560 ret
= asprintf(<tng_path
, "%s/lttng", debugfs_path
);
1562 perror("asprintf lttng path");
1566 /* Open debugfs lttng */
1567 kernel_tracer_fd
= open(lttng_path
, O_RDWR
);
1568 if (kernel_tracer_fd
< 0) {
1569 DBG("Failed to open %s", lttng_path
);
1575 DBG("Kernel tracer fd %d", kernel_tracer_fd
);
1585 WARN("No kernel tracer available");
1586 kernel_tracer_fd
= 0;
1591 * Init tracing by creating trace directory and sending fds kernel consumer.
1593 static int init_kernel_tracing(struct ltt_kernel_session
*session
)
1597 if (session
->kconsumer_fds_sent
== 0) {
1599 * Assign default kernel consumer socket if no consumer assigned to the
1600 * kernel session. At this point, it's NOT suppose to be 0 but this is
1601 * an extra security check.
1603 if (session
->consumer_fd
== 0) {
1604 session
->consumer_fd
= kconsumerd_cmd_sock
;
1607 ret
= send_kconsumerd_fds(session
);
1609 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1613 session
->kconsumer_fds_sent
= 1;
1621 * Create an UST session and add it to the session ust list.
1623 static int create_ust_session(pid_t pid
, struct ltt_session
*session
)
1626 struct ltt_ust_session
*lus
;
1628 DBG("Creating UST session");
1630 lus
= trace_ust_create_session(session
->path
, pid
);
1635 ret
= mkdir_recursive(lus
->path
, S_IRWXU
| S_IRWXG
,
1636 geteuid(), allowed_group());
1638 if (ret
!= -EEXIST
) {
1639 ERR("Trace directory creation error");
1644 /* Create session on the UST tracer */
1645 ret
= ustctl_create_session(lus
);
1658 * Create a kernel tracer session then create the default channel.
1660 static int create_kernel_session(struct ltt_session
*session
)
1664 DBG("Creating kernel session");
1666 ret
= kernel_create_session(session
, kernel_tracer_fd
);
1668 ret
= LTTCOMM_KERN_SESS_FAIL
;
1672 /* Set kernel consumer socket fd */
1673 if (kconsumerd_cmd_sock
) {
1674 session
->kernel_session
->consumer_fd
= kconsumerd_cmd_sock
;
1677 ret
= mkdir_recursive(session
->kernel_session
->trace_path
,
1678 S_IRWXU
| S_IRWXG
, geteuid(), allowed_group());
1680 if (ret
!= -EEXIST
) {
1681 ERR("Trace directory creation error");
1691 * Using the session list, filled a lttng_session array to send back to the
1692 * client for session listing.
1694 * The session list lock MUST be acquired before calling this function. Use
1695 * session_lock_list() and session_unlock_list().
1697 static void list_lttng_sessions(struct lttng_session
*sessions
)
1700 struct ltt_session
*session
;
1702 DBG("Getting all available session");
1704 * Iterate over session list and append data after the control struct in
1707 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
1708 strncpy(sessions
[i
].path
, session
->path
, PATH_MAX
);
1709 sessions
[i
].path
[PATH_MAX
- 1] = '\0';
1710 strncpy(sessions
[i
].name
, session
->name
, NAME_MAX
);
1711 sessions
[i
].name
[NAME_MAX
- 1] = '\0';
1717 * Fill lttng_channel array of all channels.
1719 static void list_lttng_channels(struct ltt_session
*session
,
1720 struct lttng_channel
*channels
)
1723 struct ltt_kernel_channel
*kchan
;
1725 DBG("Listing channels for session %s", session
->name
);
1727 /* Kernel channels */
1728 if (session
->kernel_session
!= NULL
) {
1729 cds_list_for_each_entry(kchan
,
1730 &session
->kernel_session
->channel_list
.head
, list
) {
1731 /* Copy lttng_channel struct to array */
1732 memcpy(&channels
[i
], kchan
->channel
, sizeof(struct lttng_channel
));
1733 channels
[i
].enabled
= kchan
->enabled
;
1738 /* TODO: Missing UST listing */
1742 * Fill lttng_event array of all events in the channel.
1744 static void list_lttng_events(struct ltt_kernel_channel
*kchan
,
1745 struct lttng_event
*events
)
1748 * TODO: This is ONLY kernel. Need UST support.
1751 struct ltt_kernel_event
*event
;
1753 DBG("Listing events for channel %s", kchan
->channel
->name
);
1755 /* Kernel channels */
1756 cds_list_for_each_entry(event
, &kchan
->events_list
.head
, list
) {
1757 strncpy(events
[i
].name
, event
->event
->name
, LTTNG_SYMBOL_NAME_LEN
);
1758 events
[i
].name
[LTTNG_SYMBOL_NAME_LEN
- 1] = '\0';
1759 events
[i
].enabled
= event
->enabled
;
1760 switch (event
->event
->instrumentation
) {
1761 case LTTNG_KERNEL_TRACEPOINT
:
1762 events
[i
].type
= LTTNG_EVENT_TRACEPOINT
;
1764 case LTTNG_KERNEL_KPROBE
:
1765 case LTTNG_KERNEL_KRETPROBE
:
1766 events
[i
].type
= LTTNG_EVENT_PROBE
;
1767 memcpy(&events
[i
].attr
.probe
, &event
->event
->u
.kprobe
,
1768 sizeof(struct lttng_kernel_kprobe
));
1770 case LTTNG_KERNEL_FUNCTION
:
1771 events
[i
].type
= LTTNG_EVENT_FUNCTION
;
1772 memcpy(&events
[i
].attr
.ftrace
, &event
->event
->u
.ftrace
,
1773 sizeof(struct lttng_kernel_function
));
1775 case LTTNG_KERNEL_NOOP
:
1776 events
[i
].type
= LTTNG_EVENT_NOOP
;
1778 case LTTNG_KERNEL_SYSCALL
:
1779 events
[i
].type
= LTTNG_EVENT_SYSCALL
;
1787 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1789 static int cmd_disable_channel(struct ltt_session
*session
,
1790 int domain
, char *channel_name
)
1795 case LTTNG_DOMAIN_KERNEL
:
1796 ret
= channel_kernel_disable(session
->kernel_session
,
1798 if (ret
!= LTTCOMM_OK
) {
1802 kernel_wait_quiescent(kernel_tracer_fd
);
1805 /* TODO: Userspace tracing */
1806 ret
= LTTCOMM_NOT_IMPLEMENTED
;
1817 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1819 static int cmd_enable_channel(struct ltt_session
*session
, int domain
,
1820 char *channel_name
, struct lttng_channel
*attr
)
1823 struct ltt_kernel_channel
*kchan
;
1826 case LTTNG_DOMAIN_KERNEL
:
1827 kchan
= trace_kernel_get_channel_by_name(channel_name
,
1828 session
->kernel_session
);
1829 if (kchan
== NULL
) {
1830 ret
= channel_kernel_create(session
->kernel_session
,
1831 channel_name
, attr
, kernel_poll_pipe
[1]);
1833 ret
= channel_kernel_enable(session
->kernel_session
, kchan
);
1836 if (ret
!= LTTCOMM_OK
) {
1840 kernel_wait_quiescent(kernel_tracer_fd
);
1843 /* TODO: Userspace tracing */
1844 ret
= LTTCOMM_NOT_IMPLEMENTED
;
1855 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1857 static int cmd_disable_event(struct ltt_session
*session
, int domain
,
1858 char *channel_name
, char *event_name
)
1861 struct ltt_kernel_channel
*kchan
;
1864 case LTTNG_DOMAIN_KERNEL
:
1865 kchan
= trace_kernel_get_channel_by_name(channel_name
,
1866 session
->kernel_session
);
1867 if (kchan
== NULL
) {
1868 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
1872 ret
= event_kernel_disable(session
->kernel_session
, kchan
, event_name
);
1873 if (ret
!= LTTCOMM_OK
) {
1877 kernel_wait_quiescent(kernel_tracer_fd
);
1880 /* TODO: Userspace tracing */
1881 ret
= LTTCOMM_NOT_IMPLEMENTED
;
1892 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
1894 static int cmd_disable_event_all(struct ltt_session
*session
, int domain
,
1898 struct ltt_kernel_channel
*kchan
;
1901 case LTTNG_DOMAIN_KERNEL
:
1902 kchan
= trace_kernel_get_channel_by_name(channel_name
,
1903 session
->kernel_session
);
1904 if (kchan
== NULL
) {
1905 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
1909 ret
= event_kernel_disable_all(session
->kernel_session
, kchan
);
1910 if (ret
!= LTTCOMM_OK
) {
1914 kernel_wait_quiescent(kernel_tracer_fd
);
1917 /* TODO: Userspace tracing */
1918 ret
= LTTCOMM_NOT_IMPLEMENTED
;
1929 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1931 static int cmd_add_context(struct ltt_session
*session
, int domain
,
1932 char *channel_name
, char *event_name
, struct lttng_event_context
*ctx
)
1937 case LTTNG_DOMAIN_KERNEL
:
1938 /* Add kernel context to kernel tracer */
1939 ret
= context_kernel_add(session
->kernel_session
, ctx
,
1940 event_name
, channel_name
);
1941 if (ret
!= LTTCOMM_OK
) {
1947 /* TODO: Userspace tracing */
1948 ret
= LTTCOMM_NOT_IMPLEMENTED
;
1959 * Command LTTNG_ENABLE_EVENT processed by the client thread.
1961 static int cmd_enable_event(struct ltt_session
*session
, int domain
,
1962 char *channel_name
, struct lttng_event
*event
)
1965 struct ltt_kernel_channel
*kchan
;
1968 case LTTNG_DOMAIN_KERNEL
:
1969 kchan
= trace_kernel_get_channel_by_name(channel_name
,
1970 session
->kernel_session
);
1971 if (kchan
== NULL
) {
1972 /* This call will notify the kernel thread */
1973 ret
= channel_kernel_create(session
->kernel_session
, channel_name
,
1974 NULL
, kernel_poll_pipe
[1]);
1975 if (ret
!= LTTCOMM_OK
) {
1980 /* Get the newly created kernel channel pointer */
1981 kchan
= trace_kernel_get_channel_by_name(channel_name
,
1982 session
->kernel_session
);
1983 if (kchan
== NULL
) {
1984 /* This sould not happen... */
1985 ret
= LTTCOMM_FATAL
;
1989 ret
= event_kernel_enable(session
->kernel_session
, kchan
, event
);
1990 if (ret
!= LTTCOMM_OK
) {
1994 kernel_wait_quiescent(kernel_tracer_fd
);
1997 /* TODO: Userspace tracing */
1998 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2009 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2011 static int cmd_enable_event_all(struct ltt_session
*session
, int domain
,
2015 struct ltt_kernel_channel
*kchan
;
2018 case LTTNG_DOMAIN_KERNEL
:
2019 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2020 session
->kernel_session
);
2021 if (kchan
== NULL
) {
2022 /* This call will notify the kernel thread */
2023 ret
= channel_kernel_create(session
->kernel_session
, channel_name
,
2024 NULL
, kernel_poll_pipe
[1]);
2025 if (ret
!= LTTCOMM_OK
) {
2030 /* Get the newly created kernel channel pointer */
2031 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2032 session
->kernel_session
);
2033 if (kchan
== NULL
) {
2034 /* This sould not happen... */
2035 ret
= LTTCOMM_FATAL
;
2039 ret
= event_kernel_enable_all(session
->kernel_session
,
2040 kchan
, kernel_tracer_fd
);
2041 if (ret
!= LTTCOMM_OK
) {
2045 kernel_wait_quiescent(kernel_tracer_fd
);
2048 /* TODO: Userspace tracing */
2049 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2060 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2062 static ssize_t
cmd_list_tracepoints(int domain
, struct lttng_event
**events
)
2065 ssize_t nb_events
= 0;
2068 case LTTNG_DOMAIN_KERNEL
:
2069 nb_events
= kernel_list_events(kernel_tracer_fd
, events
);
2070 if (nb_events
< 0) {
2071 ret
= LTTCOMM_KERN_LIST_FAIL
;
2076 /* TODO: Userspace listing */
2077 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2084 /* Return negative value to differentiate return code */
2089 * Command LTTNG_START_TRACE processed by the client thread.
2091 static int cmd_start_trace(struct ltt_session
*session
)
2094 struct ltt_kernel_channel
*kchan
;
2095 struct ltt_kernel_session
*ksession
;
2098 ksession
= session
->kernel_session
;
2100 /* Kernel tracing */
2101 if (ksession
!= NULL
) {
2102 /* Open kernel metadata */
2103 if (ksession
->metadata
== NULL
) {
2104 ret
= kernel_open_metadata(ksession
, ksession
->trace_path
);
2106 ret
= LTTCOMM_KERN_META_FAIL
;
2111 /* Open kernel metadata stream */
2112 if (ksession
->metadata_stream_fd
== 0) {
2113 ret
= kernel_open_metadata_stream(ksession
);
2115 ERR("Kernel create metadata stream failed");
2116 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2121 /* For each channel */
2122 cds_list_for_each_entry(kchan
, &ksession
->channel_list
.head
, list
) {
2123 if (kchan
->stream_count
== 0) {
2124 ret
= kernel_open_channel_stream(kchan
);
2126 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2129 /* Update the stream global counter */
2130 ksession
->stream_count_global
+= ret
;
2134 /* Setup kernel consumer socket and send fds to it */
2135 ret
= init_kernel_tracing(ksession
);
2137 ret
= LTTCOMM_KERN_START_FAIL
;
2141 /* This start the kernel tracing */
2142 ret
= kernel_start_session(ksession
);
2144 ret
= LTTCOMM_KERN_START_FAIL
;
2148 /* Quiescent wait after starting trace */
2149 kernel_wait_quiescent(kernel_tracer_fd
);
2152 /* TODO: Start all UST traces */
2161 * Command LTTNG_STOP_TRACE processed by the client thread.
2163 static int cmd_stop_trace(struct ltt_session
*session
)
2166 struct ltt_kernel_channel
*kchan
;
2167 struct ltt_kernel_session
*ksession
;
2170 ksession
= session
->kernel_session
;
2173 if (ksession
!= NULL
) {
2174 DBG("Stop kernel tracing");
2176 /* Flush all buffers before stopping */
2177 ret
= kernel_metadata_flush_buffer(ksession
->metadata_stream_fd
);
2179 ERR("Kernel metadata flush failed");
2182 cds_list_for_each_entry(kchan
, &ksession
->channel_list
.head
, list
) {
2183 ret
= kernel_flush_buffer(kchan
);
2185 ERR("Kernel flush buffer error");
2189 ret
= kernel_stop_session(ksession
);
2191 ret
= LTTCOMM_KERN_STOP_FAIL
;
2195 kernel_wait_quiescent(kernel_tracer_fd
);
2198 /* TODO : User-space tracer */
2207 * Command LTTNG_CREATE_SESSION processed by the client thread.
2209 static int cmd_create_session(char *name
, char *path
)
2213 ret
= session_create(name
, path
);
2214 if (ret
!= LTTCOMM_OK
) {
2225 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2227 static int cmd_destroy_session(struct ltt_session
*session
, char *name
)
2231 /* Clean kernel session teardown */
2232 teardown_kernel_session(session
);
2235 * Must notify the kernel thread here to update it's poll setin order
2236 * to remove the channel(s)' fd just destroyed.
2238 ret
= notify_thread_pipe(kernel_poll_pipe
[1]);
2240 perror("write kernel poll pipe");
2243 ret
= session_destroy(name
);
2249 * Command LTTNG_CALIBRATE processed by the client thread.
2251 static int cmd_calibrate(int domain
, struct lttng_calibrate
*calibrate
)
2256 case LTTNG_DOMAIN_KERNEL
:
2258 struct lttng_kernel_calibrate kcalibrate
;
2260 kcalibrate
.type
= calibrate
->type
;
2261 ret
= kernel_calibrate(kernel_tracer_fd
, &kcalibrate
);
2263 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2269 /* TODO: Userspace tracing */
2270 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2281 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2283 static int cmd_register_consumer(struct ltt_session
*session
, int domain
,
2289 case LTTNG_DOMAIN_KERNEL
:
2290 /* Can't register a consumer if there is already one */
2291 if (session
->kernel_session
->consumer_fd
!= 0) {
2292 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
2296 sock
= lttcomm_connect_unix_sock(sock_path
);
2298 ret
= LTTCOMM_CONNECT_FAIL
;
2302 session
->kernel_session
->consumer_fd
= sock
;
2305 /* TODO: Userspace tracing */
2306 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2317 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2319 static ssize_t
cmd_list_domains(struct ltt_session
*session
,
2320 struct lttng_domain
**domains
)
2325 if (session
->kernel_session
!= NULL
) {
2329 nb_dom
+= session
->ust_session_list
.count
;
2331 *domains
= malloc(nb_dom
* sizeof(struct lttng_domain
));
2332 if (*domains
== NULL
) {
2333 ret
= -LTTCOMM_FATAL
;
2337 (*domains
)[0].type
= LTTNG_DOMAIN_KERNEL
;
2339 /* TODO: User-space tracer domain support */
2348 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2350 static ssize_t
cmd_list_channels(struct ltt_session
*session
,
2351 struct lttng_channel
**channels
)
2354 ssize_t nb_chan
= 0;
2356 if (session
->kernel_session
!= NULL
) {
2357 nb_chan
+= session
->kernel_session
->channel_count
;
2360 *channels
= malloc(nb_chan
* sizeof(struct lttng_channel
));
2361 if (*channels
== NULL
) {
2362 ret
= -LTTCOMM_FATAL
;
2366 list_lttng_channels(session
, *channels
);
2375 * Command LTTNG_LIST_EVENTS processed by the client thread.
2377 static ssize_t
cmd_list_events(struct ltt_session
*session
,
2378 char *channel_name
, struct lttng_event
**events
)
2381 ssize_t nb_event
= 0;
2382 struct ltt_kernel_channel
*kchan
= NULL
;
2384 if (session
->kernel_session
!= NULL
) {
2385 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2386 session
->kernel_session
);
2387 if (kchan
== NULL
) {
2388 ret
= -LTTCOMM_KERN_CHAN_NOT_FOUND
;
2391 nb_event
+= kchan
->event_count
;
2394 *events
= malloc(nb_event
* sizeof(struct lttng_event
));
2395 if (*events
== NULL
) {
2396 ret
= -LTTCOMM_FATAL
;
2400 list_lttng_events(kchan
, *events
);
2402 /* TODO: User-space tracer support */
2411 * Process the command requested by the lttng client within the command
2412 * context structure. This function make sure that the return structure (llm)
2413 * is set and ready for transmission before returning.
2415 * Return any error encountered or 0 for success.
2417 static int process_client_msg(struct command_ctx
*cmd_ctx
)
2419 int ret
= LTTCOMM_OK
;
2420 int need_kernel_session
= 1;
2422 DBG("Processing client command %d", cmd_ctx
->lsm
->cmd_type
);
2425 * Check for command that don't needs to allocate a returned payload. We do
2426 * this here so we don't have to make the call for no payload" at each
2429 switch(cmd_ctx
->lsm
->cmd_type
) {
2430 case LTTNG_LIST_SESSIONS
:
2431 case LTTNG_LIST_TRACEPOINTS
:
2432 case LTTNG_LIST_DOMAINS
:
2433 case LTTNG_LIST_CHANNELS
:
2434 case LTTNG_LIST_EVENTS
:
2437 /* Setup lttng message with no payload */
2438 ret
= setup_lttng_msg(cmd_ctx
, 0);
2440 /* This label does not try to unlock the session */
2441 goto init_setup_error
;
2445 /* Commands that DO NOT need a session. */
2446 switch (cmd_ctx
->lsm
->cmd_type
) {
2447 case LTTNG_CALIBRATE
:
2448 case LTTNG_CREATE_SESSION
:
2449 case LTTNG_LIST_SESSIONS
:
2450 case LTTNG_LIST_TRACEPOINTS
:
2451 need_kernel_session
= 0;
2454 DBG("Getting session %s by name", cmd_ctx
->lsm
->session
.name
);
2455 cmd_ctx
->session
= session_find_by_name(cmd_ctx
->lsm
->session
.name
);
2456 if (cmd_ctx
->session
== NULL
) {
2457 if (cmd_ctx
->lsm
->session
.name
!= NULL
) {
2458 ret
= LTTCOMM_SESS_NOT_FOUND
;
2460 /* If no session name specified */
2461 ret
= LTTCOMM_SELECT_SESS
;
2465 /* Acquire lock for the session */
2466 session_lock(cmd_ctx
->session
);
2472 * Check domain type for specific "pre-action".
2474 switch (cmd_ctx
->lsm
->domain
.type
) {
2475 case LTTNG_DOMAIN_KERNEL
:
2476 /* Kernel tracer check */
2477 if (kernel_tracer_fd
== 0) {
2478 /* Basically, load kernel tracer modules */
2479 init_kernel_tracer();
2480 if (kernel_tracer_fd
== 0) {
2481 ret
= LTTCOMM_KERN_NA
;
2486 /* Need a session for kernel command */
2487 if (need_kernel_session
) {
2488 if (cmd_ctx
->session
->kernel_session
== NULL
) {
2489 ret
= create_kernel_session(cmd_ctx
->session
);
2491 ret
= LTTCOMM_KERN_SESS_FAIL
;
2496 /* Start the kernel consumer daemon */
2497 if (kconsumerd_pid
== 0 &&
2498 cmd_ctx
->lsm
->cmd_type
!= LTTNG_REGISTER_CONSUMER
) {
2499 ret
= start_kconsumerd();
2501 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
2508 /* TODO Userspace tracer */
2512 /* Process by command type */
2513 switch (cmd_ctx
->lsm
->cmd_type
) {
2514 case LTTNG_ADD_CONTEXT
:
2516 ret
= cmd_add_context(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2517 cmd_ctx
->lsm
->u
.context
.channel_name
,
2518 cmd_ctx
->lsm
->u
.context
.event_name
,
2519 &cmd_ctx
->lsm
->u
.context
.ctx
);
2522 case LTTNG_DISABLE_CHANNEL
:
2524 ret
= cmd_disable_channel(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2525 cmd_ctx
->lsm
->u
.disable
.channel_name
);
2528 case LTTNG_DISABLE_EVENT
:
2530 ret
= cmd_disable_event(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2531 cmd_ctx
->lsm
->u
.disable
.channel_name
,
2532 cmd_ctx
->lsm
->u
.disable
.name
);
2536 case LTTNG_DISABLE_ALL_EVENT
:
2538 DBG("Disabling all kernel event");
2540 ret
= cmd_disable_event_all(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2541 cmd_ctx
->lsm
->u
.disable
.channel_name
);
2544 case LTTNG_ENABLE_CHANNEL
:
2546 ret
= cmd_enable_channel(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2547 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2548 &cmd_ctx
->lsm
->u
.channel
.chan
);
2551 case LTTNG_ENABLE_EVENT
:
2553 ret
= cmd_enable_event(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2554 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2555 &cmd_ctx
->lsm
->u
.enable
.event
);
2558 case LTTNG_ENABLE_ALL_EVENT
:
2560 DBG("Enabling all kernel event");
2562 ret
= cmd_enable_event_all(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2563 cmd_ctx
->lsm
->u
.enable
.channel_name
);
2566 case LTTNG_LIST_TRACEPOINTS
:
2568 struct lttng_event
*events
;
2571 nb_events
= cmd_list_tracepoints(cmd_ctx
->lsm
->domain
.type
, &events
);
2572 if (nb_events
< 0) {
2578 * Setup lttng message with payload size set to the event list size in
2579 * bytes and then copy list into the llm payload.
2581 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_event
) * nb_events
);
2587 /* Copy event list into message payload */
2588 memcpy(cmd_ctx
->llm
->payload
, events
,
2589 sizeof(struct lttng_event
) * nb_events
);
2596 case LTTNG_START_TRACE
:
2598 ret
= cmd_start_trace(cmd_ctx
->session
);
2601 case LTTNG_STOP_TRACE
:
2603 ret
= cmd_stop_trace(cmd_ctx
->session
);
2606 case LTTNG_CREATE_SESSION
:
2608 tracepoint(create_session_start
);
2609 ret
= cmd_create_session(cmd_ctx
->lsm
->session
.name
,
2610 cmd_ctx
->lsm
->session
.path
);
2611 tracepoint(create_session_end
);
2614 case LTTNG_DESTROY_SESSION
:
2616 tracepoint(destroy_session_start
);
2617 ret
= cmd_destroy_session(cmd_ctx
->session
,
2618 cmd_ctx
->lsm
->session
.name
);
2619 tracepoint(destroy_session_end
);
2622 case LTTNG_LIST_DOMAINS
:
2625 struct lttng_domain
*domains
;
2627 nb_dom
= cmd_list_domains(cmd_ctx
->session
, &domains
);
2633 ret
= setup_lttng_msg(cmd_ctx
, nb_dom
* sizeof(struct lttng_domain
));
2638 /* Copy event list into message payload */
2639 memcpy(cmd_ctx
->llm
->payload
, domains
,
2640 nb_dom
* sizeof(struct lttng_domain
));
2647 case LTTNG_LIST_CHANNELS
:
2650 struct lttng_channel
*channels
;
2652 nb_chan
= cmd_list_channels(cmd_ctx
->session
, &channels
);
2658 ret
= setup_lttng_msg(cmd_ctx
, nb_chan
* sizeof(struct lttng_channel
));
2663 /* Copy event list into message payload */
2664 memcpy(cmd_ctx
->llm
->payload
, channels
,
2665 nb_chan
* sizeof(struct lttng_channel
));
2672 case LTTNG_LIST_EVENTS
:
2675 struct lttng_event
*events
= NULL
;
2677 nb_event
= cmd_list_events(cmd_ctx
->session
,
2678 cmd_ctx
->lsm
->u
.list
.channel_name
, &events
);
2684 ret
= setup_lttng_msg(cmd_ctx
, nb_event
* sizeof(struct lttng_event
));
2689 /* Copy event list into message payload */
2690 memcpy(cmd_ctx
->llm
->payload
, events
,
2691 nb_event
* sizeof(struct lttng_event
));
2698 case LTTNG_LIST_SESSIONS
:
2700 session_lock_list();
2702 if (session_list_ptr
->count
== 0) {
2703 ret
= LTTCOMM_NO_SESSION
;
2704 session_unlock_list();
2708 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_session
) *
2709 session_list_ptr
->count
);
2711 session_unlock_list();
2715 /* Filled the session array */
2716 list_lttng_sessions((struct lttng_session
*)(cmd_ctx
->llm
->payload
));
2718 session_unlock_list();
2723 case LTTNG_CALIBRATE
:
2725 ret
= cmd_calibrate(cmd_ctx
->lsm
->domain
.type
,
2726 &cmd_ctx
->lsm
->u
.calibrate
);
2729 case LTTNG_REGISTER_CONSUMER
:
2731 ret
= cmd_register_consumer(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2732 cmd_ctx
->lsm
->u
.reg
.path
);
2741 if (cmd_ctx
->llm
== NULL
) {
2742 DBG("Missing llm structure. Allocating one.");
2743 if (setup_lttng_msg(cmd_ctx
, 0) < 0) {
2747 /* Set return code */
2748 cmd_ctx
->llm
->ret_code
= ret
;
2750 if (cmd_ctx
->session
) {
2751 session_unlock(cmd_ctx
->session
);
2758 * This thread manage all clients request using the unix client socket for
2761 static void *thread_manage_clients(void *data
)
2763 int sock
= 0, ret
, i
, pollfd
;
2764 uint32_t revents
, nb_fd
;
2765 struct command_ctx
*cmd_ctx
= NULL
;
2766 struct lttng_poll_event events
;
2768 tracepoint(sessiond_th_cli_start
);
2770 DBG("[thread] Manage client started");
2772 ret
= lttcomm_listen_unix_sock(client_sock
);
2778 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2779 * more will be added to this poll set.
2781 ret
= create_thread_poll_set(&events
, 2);
2786 /* Add the application registration socket */
2787 ret
= lttng_poll_add(&events
, client_sock
, LPOLLIN
| LPOLLPRI
);
2793 * Notify parent pid that we are ready to accept command for client side.
2795 if (opt_sig_parent
) {
2796 kill(ppid
, SIGCHLD
);
2800 DBG("Accepting client command ...");
2802 tracepoint(sessiond_th_cli_poll
);
2804 nb_fd
= LTTNG_POLL_GETNB(&events
);
2806 /* Inifinite blocking call, waiting for transmission */
2807 ret
= lttng_poll_wait(&events
, -1);
2812 for (i
= 0; i
< nb_fd
; i
++) {
2813 /* Fetch once the poll data */
2814 revents
= LTTNG_POLL_GETEV(&events
, i
);
2815 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2817 /* Thread quit pipe has been closed. Killing thread. */
2818 ret
= check_thread_quit_pipe(pollfd
, revents
);
2823 /* Event on the registration socket */
2824 if (pollfd
== client_sock
) {
2825 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
2826 ERR("Client socket poll error");
2832 DBG("Wait for client response");
2834 sock
= lttcomm_accept_unix_sock(client_sock
);
2839 /* Allocate context command to process the client request */
2840 cmd_ctx
= malloc(sizeof(struct command_ctx
));
2841 if (cmd_ctx
== NULL
) {
2842 perror("malloc cmd_ctx");
2846 /* Allocate data buffer for reception */
2847 cmd_ctx
->lsm
= malloc(sizeof(struct lttcomm_session_msg
));
2848 if (cmd_ctx
->lsm
== NULL
) {
2849 perror("malloc cmd_ctx->lsm");
2853 cmd_ctx
->llm
= NULL
;
2854 cmd_ctx
->session
= NULL
;
2857 * Data is received from the lttng client. The struct
2858 * lttcomm_session_msg (lsm) contains the command and data request of
2861 DBG("Receiving data from client ...");
2862 ret
= lttcomm_recv_unix_sock(sock
, cmd_ctx
->lsm
,
2863 sizeof(struct lttcomm_session_msg
));
2865 DBG("Nothing recv() from client... continuing");
2871 // TODO: Validate cmd_ctx including sanity check for
2872 // security purpose.
2875 * This function dispatch the work to the kernel or userspace tracer
2876 * libs and fill the lttcomm_lttng_msg data structure of all the needed
2877 * informations for the client. The command context struct contains
2878 * everything this function may needs.
2880 ret
= process_client_msg(cmd_ctx
);
2883 * TODO: Inform client somehow of the fatal error. At
2884 * this point, ret < 0 means that a malloc failed
2885 * (ENOMEM). Error detected but still accept command.
2887 clean_command_ctx(&cmd_ctx
);
2891 DBG("Sending response (size: %d, retcode: %s)",
2892 cmd_ctx
->lttng_msg_size
,
2893 lttng_get_readable_code(cmd_ctx
->llm
->ret_code
));
2894 ret
= send_unix_sock(sock
, cmd_ctx
->llm
, cmd_ctx
->lttng_msg_size
);
2896 ERR("Failed to send data back to client");
2899 clean_command_ctx(&cmd_ctx
);
2901 /* End of transmission */
2906 DBG("Client thread dying");
2907 unlink(client_unix_sock_path
);
2911 lttng_poll_clean(&events
);
2912 clean_command_ctx(&cmd_ctx
);
2918 * usage function on stderr
2920 static void usage(void)
2922 fprintf(stderr
, "Usage: %s OPTIONS\n\nOptions:\n", progname
);
2923 fprintf(stderr
, " -h, --help Display this usage.\n");
2924 fprintf(stderr
, " -c, --client-sock PATH Specify path for the client unix socket\n");
2925 fprintf(stderr
, " -a, --apps-sock PATH Specify path for apps unix socket\n");
2926 fprintf(stderr
, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
2927 fprintf(stderr
, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
2928 fprintf(stderr
, " -d, --daemonize Start as a daemon.\n");
2929 fprintf(stderr
, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
2930 fprintf(stderr
, " -V, --version Show version number.\n");
2931 fprintf(stderr
, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
2932 fprintf(stderr
, " -q, --quiet No output at all.\n");
2933 fprintf(stderr
, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
2934 fprintf(stderr
, " --verbose-kconsumerd Verbose mode for kconsumerd. Activate DBG() macro.\n");
2938 * daemon argument parsing
2940 static int parse_args(int argc
, char **argv
)
2944 static struct option long_options
[] = {
2945 { "client-sock", 1, 0, 'c' },
2946 { "apps-sock", 1, 0, 'a' },
2947 { "kconsumerd-cmd-sock", 1, 0, 0 },
2948 { "kconsumerd-err-sock", 1, 0, 0 },
2949 { "daemonize", 0, 0, 'd' },
2950 { "sig-parent", 0, 0, 'S' },
2951 { "help", 0, 0, 'h' },
2952 { "group", 1, 0, 'g' },
2953 { "version", 0, 0, 'V' },
2954 { "quiet", 0, 0, 'q' },
2955 { "verbose", 0, 0, 'v' },
2956 { "verbose-kconsumerd", 0, 0, 'Z' },
2961 int option_index
= 0;
2962 c
= getopt_long(argc
, argv
, "dhqvVS" "a:c:g:s:E:C:Z",
2963 long_options
, &option_index
);
2970 fprintf(stderr
, "option %s", long_options
[option_index
].name
);
2972 fprintf(stderr
, " with arg %s\n", optarg
);
2976 snprintf(client_unix_sock_path
, PATH_MAX
, "%s", optarg
);
2979 snprintf(apps_unix_sock_path
, PATH_MAX
, "%s", optarg
);
2985 opt_tracing_group
= strdup(optarg
);
2991 fprintf(stdout
, "%s\n", VERSION
);
2997 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3000 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3006 /* Verbose level can increase using multiple -v */
3010 opt_verbose_kconsumerd
+= 1;
3013 /* Unknown option or other error.
3014 * Error is printed by getopt, just return */
3023 * Creates the two needed socket by the daemon.
3024 * apps_sock - The communication socket for all UST apps.
3025 * client_sock - The communication of the cli tool (lttng).
3027 static int init_daemon_socket(void)
3032 old_umask
= umask(0);
3034 /* Create client tool unix socket */
3035 client_sock
= lttcomm_create_unix_sock(client_unix_sock_path
);
3036 if (client_sock
< 0) {
3037 ERR("Create unix sock failed: %s", client_unix_sock_path
);
3042 /* File permission MUST be 660 */
3043 ret
= chmod(client_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3045 ERR("Set file permissions failed: %s", client_unix_sock_path
);
3050 /* Create the application unix socket */
3051 apps_sock
= lttcomm_create_unix_sock(apps_unix_sock_path
);
3052 if (apps_sock
< 0) {
3053 ERR("Create unix sock failed: %s", apps_unix_sock_path
);
3058 /* File permission MUST be 666 */
3059 ret
= chmod(apps_unix_sock_path
,
3060 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
| S_IROTH
| S_IWOTH
);
3062 ERR("Set file permissions failed: %s", apps_unix_sock_path
);
3073 * Check if the global socket is available, and if a daemon is answering at the
3074 * other side. If yes, error is returned.
3076 static int check_existing_daemon(void)
3078 if (access(client_unix_sock_path
, F_OK
) < 0 &&
3079 access(apps_unix_sock_path
, F_OK
) < 0) {
3083 /* Is there anybody out there ? */
3084 if (lttng_session_daemon_alive()) {
3092 * Set the tracing group gid onto the client socket.
3094 * Race window between mkdir and chown is OK because we are going from more
3095 * permissive (root.root) to les permissive (root.tracing).
3097 static int set_permissions(void)
3102 gid
= allowed_group();
3105 WARN("No tracing group detected");
3108 ERR("Missing tracing group. Aborting execution.");
3114 /* Set lttng run dir */
3115 ret
= chown(LTTNG_RUNDIR
, 0, gid
);
3117 ERR("Unable to set group on " LTTNG_RUNDIR
);
3121 /* lttng client socket path */
3122 ret
= chown(client_unix_sock_path
, 0, gid
);
3124 ERR("Unable to set group on %s", client_unix_sock_path
);
3128 /* kconsumerd error socket path */
3129 ret
= chown(kconsumerd_err_unix_sock_path
, 0, gid
);
3131 ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path
);
3135 DBG("All permissions are set");
3142 * Create the pipe used to wake up the kernel thread.
3144 static int create_kernel_poll_pipe(void)
3146 return pipe2(kernel_poll_pipe
, O_CLOEXEC
);
3150 * Create the application command pipe to wake thread_manage_apps.
3152 static int create_apps_cmd_pipe(void)
3154 return pipe2(apps_cmd_pipe
, O_CLOEXEC
);
3158 * Create the lttng run directory needed for all global sockets and pipe.
3160 static int create_lttng_rundir(void)
3164 ret
= mkdir(LTTNG_RUNDIR
, S_IRWXU
| S_IRWXG
);
3166 if (errno
!= EEXIST
) {
3167 ERR("Unable to create " LTTNG_RUNDIR
);
3179 * Setup sockets and directory needed by the kconsumerd communication with the
3182 static int set_kconsumerd_sockets(void)
3186 if (strlen(kconsumerd_err_unix_sock_path
) == 0) {
3187 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
,
3188 KCONSUMERD_ERR_SOCK_PATH
);
3191 if (strlen(kconsumerd_cmd_unix_sock_path
) == 0) {
3192 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
,
3193 KCONSUMERD_CMD_SOCK_PATH
);
3196 ret
= mkdir(KCONSUMERD_PATH
, S_IRWXU
| S_IRWXG
);
3198 if (errno
!= EEXIST
) {
3199 ERR("Failed to create " KCONSUMERD_PATH
);
3205 /* Create the kconsumerd error unix socket */
3206 kconsumerd_err_sock
=
3207 lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path
);
3208 if (kconsumerd_err_sock
< 0) {
3209 ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path
);
3214 /* File permission MUST be 660 */
3215 ret
= chmod(kconsumerd_err_unix_sock_path
,
3216 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3218 ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path
);
3228 * Signal handler for the daemon
3230 * Simply stop all worker threads, leaving main() return gracefully after
3231 * joining all threads and calling cleanup().
3233 static void sighandler(int sig
)
3237 DBG("SIGPIPE catched");
3240 DBG("SIGINT catched");
3244 DBG("SIGTERM catched");
3253 * Setup signal handler for :
3254 * SIGINT, SIGTERM, SIGPIPE
3256 static int set_signal_handler(void)
3259 struct sigaction sa
;
3262 if ((ret
= sigemptyset(&sigset
)) < 0) {
3263 perror("sigemptyset");
3267 sa
.sa_handler
= sighandler
;
3268 sa
.sa_mask
= sigset
;
3270 if ((ret
= sigaction(SIGTERM
, &sa
, NULL
)) < 0) {
3271 perror("sigaction");
3275 if ((ret
= sigaction(SIGINT
, &sa
, NULL
)) < 0) {
3276 perror("sigaction");
3280 if ((ret
= sigaction(SIGPIPE
, &sa
, NULL
)) < 0) {
3281 perror("sigaction");
3285 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3291 * Set open files limit to unlimited. This daemon can open a large number of
3292 * file descriptors in order to consumer multiple kernel traces.
3294 static void set_ulimit(void)
3299 /* The kernel does not allowed an infinite limit for open files */
3300 lim
.rlim_cur
= 65535;
3301 lim
.rlim_max
= 65535;
3303 ret
= setrlimit(RLIMIT_NOFILE
, &lim
);
3305 perror("failed to set open files limit");
3312 int main(int argc
, char **argv
)
3316 const char *home_path
;
3318 tracepoint(sessiond_boot_start
);
3320 /* Create thread quit pipe */
3321 if ((ret
= init_thread_quit_pipe()) < 0) {
3325 /* Parse arguments */
3327 if ((ret
= parse_args(argc
, argv
) < 0)) {
3340 /* Check if daemon is UID = 0 */
3341 is_root
= !getuid();
3344 ret
= create_lttng_rundir();
3349 if (strlen(apps_unix_sock_path
) == 0) {
3350 snprintf(apps_unix_sock_path
, PATH_MAX
,
3351 DEFAULT_GLOBAL_APPS_UNIX_SOCK
);
3354 if (strlen(client_unix_sock_path
) == 0) {
3355 snprintf(client_unix_sock_path
, PATH_MAX
,
3356 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
);
3359 /* Set global SHM for ust */
3360 if (strlen(wait_shm_path
) == 0) {
3361 snprintf(wait_shm_path
, PATH_MAX
,
3362 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH
);
3365 home_path
= get_home_dir();
3366 if (home_path
== NULL
) {
3367 /* TODO: Add --socket PATH option */
3368 ERR("Can't get HOME directory for sockets creation.");
3373 if (strlen(apps_unix_sock_path
) == 0) {
3374 snprintf(apps_unix_sock_path
, PATH_MAX
,
3375 DEFAULT_HOME_APPS_UNIX_SOCK
, home_path
);
3378 /* Set the cli tool unix socket path */
3379 if (strlen(client_unix_sock_path
) == 0) {
3380 snprintf(client_unix_sock_path
, PATH_MAX
,
3381 DEFAULT_HOME_CLIENT_UNIX_SOCK
, home_path
);
3384 /* Set global SHM for ust */
3385 if (strlen(wait_shm_path
) == 0) {
3386 snprintf(wait_shm_path
, PATH_MAX
,
3387 DEFAULT_HOME_APPS_WAIT_SHM_PATH
, geteuid());
3391 DBG("Client socket path %s", client_unix_sock_path
);
3392 DBG("Application socket path %s", apps_unix_sock_path
);
3395 * See if daemon already exist.
3397 if ((ret
= check_existing_daemon()) < 0) {
3398 ERR("Already running daemon.\n");
3400 * We do not goto exit because we must not cleanup()
3401 * because a daemon is already running.
3406 /* After this point, we can safely call cleanup() with "goto exit" */
3409 * These actions must be executed as root. We do that *after* setting up
3410 * the sockets path because we MUST make the check for another daemon using
3411 * those paths *before* trying to set the kernel consumer sockets and init
3415 ret
= set_kconsumerd_sockets();
3420 /* Setup kernel tracer */
3421 init_kernel_tracer();
3423 /* Set ulimit for open files */
3427 if ((ret
= set_signal_handler()) < 0) {
3431 /* Setup the needed unix socket */
3432 if ((ret
= init_daemon_socket()) < 0) {
3436 /* Set credentials to socket */
3437 if (is_root
&& ((ret
= set_permissions()) < 0)) {
3441 /* Get parent pid if -S, --sig-parent is specified. */
3442 if (opt_sig_parent
) {
3446 /* Setup the kernel pipe for waking up the kernel thread */
3447 if ((ret
= create_kernel_poll_pipe()) < 0) {
3451 /* Setup the thread apps communication pipe. */
3452 if ((ret
= create_apps_cmd_pipe()) < 0) {
3456 /* Init UST command queue. */
3457 cds_wfq_init(&ust_cmd_queue
.queue
);
3460 * Get session list pointer. This pointer MUST NOT be free(). This list is
3461 * statically declared in session.c
3463 session_list_ptr
= session_get_list();
3465 /* Set up max poll set size */
3466 lttng_poll_set_max_size();
3468 /* Create thread to manage the client socket */
3469 ret
= pthread_create(&client_thread
, NULL
,
3470 thread_manage_clients
, (void *) NULL
);
3472 perror("pthread_create clients");
3476 /* Create thread to dispatch registration */
3477 ret
= pthread_create(&dispatch_thread
, NULL
,
3478 thread_dispatch_ust_registration
, (void *) NULL
);
3480 perror("pthread_create dispatch");
3484 /* Create thread to manage application registration. */
3485 ret
= pthread_create(®_apps_thread
, NULL
,
3486 thread_registration_apps
, (void *) NULL
);
3488 perror("pthread_create registration");
3492 /* Create thread to manage application socket */
3493 ret
= pthread_create(&apps_thread
, NULL
,
3494 thread_manage_apps
, (void *) NULL
);
3496 perror("pthread_create apps");
3500 /* Create kernel thread to manage kernel event */
3501 ret
= pthread_create(&kernel_thread
, NULL
,
3502 thread_manage_kernel
, (void *) NULL
);
3504 perror("pthread_create kernel");
3508 tracepoint(sessiond_boot_end
);
3510 ret
= pthread_join(kernel_thread
, &status
);
3512 perror("pthread_join");
3513 goto error
; /* join error, exit without cleanup */
3517 ret
= pthread_join(apps_thread
, &status
);
3519 perror("pthread_join");
3520 goto error
; /* join error, exit without cleanup */
3524 ret
= pthread_join(reg_apps_thread
, &status
);
3526 perror("pthread_join");
3527 goto error
; /* join error, exit without cleanup */
3531 ret
= pthread_join(dispatch_thread
, &status
);
3533 perror("pthread_join");
3534 goto error
; /* join error, exit without cleanup */
3538 ret
= pthread_join(client_thread
, &status
);
3540 perror("pthread_join");
3541 goto error
; /* join error, exit without cleanup */
3544 ret
= join_kconsumerd_thread();
3546 perror("join_kconsumerd");
3547 goto error
; /* join error, exit without cleanup */
3553 * cleanup() is called when no other thread is running.