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"
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 ust_app_clean_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) {
731 * Reset number of fd in the poll set. Always 2 since there is the thread
732 * quit pipe and the kernel pipe.
736 ret
= update_kernel_poll(&events
);
740 update_poll_flag
= 0;
743 nb_fd
= LTTNG_POLL_GETNB(&events
);
745 DBG("Thread kernel polling on %d fds", nb_fd
);
747 /* Zeroed the poll events */
748 lttng_poll_reset(&events
);
750 tracepoint(sessiond_th_kern_poll
);
752 /* Poll infinite value of time */
753 ret
= lttng_poll_wait(&events
, -1);
756 } else if (ret
== 0) {
757 /* Should not happen since timeout is infinite */
758 ERR("Return value of poll is 0 with an infinite timeout.\n"
759 "This should not have happened! Continuing...");
763 for (i
= 0; i
< nb_fd
; i
++) {
764 /* Fetch once the poll data */
765 revents
= LTTNG_POLL_GETEV(&events
, i
);
766 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
768 /* Thread quit pipe has been closed. Killing thread. */
769 ret
= check_thread_quit_pipe(pollfd
, revents
);
774 /* Check for data on kernel pipe */
775 if (pollfd
== kernel_poll_pipe
[0] && (revents
& LPOLLIN
)) {
776 ret
= read(kernel_poll_pipe
[0], &tmp
, 1);
777 update_poll_flag
= 1;
781 * New CPU detected by the kernel. Adding kernel stream to
782 * kernel session and updating the kernel consumer
784 if (revents
& LPOLLIN
) {
785 ret
= update_kernel_stream(pollfd
);
791 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
792 * and unregister kernel stream at this point.
800 DBG("Kernel thread dying");
801 close(kernel_poll_pipe
[0]);
802 close(kernel_poll_pipe
[1]);
804 lttng_poll_clean(&events
);
810 * This thread manage the kconsumerd error sent back to the session daemon.
812 static void *thread_manage_kconsumerd(void *data
)
814 int sock
= 0, i
, ret
, pollfd
;
815 uint32_t revents
, nb_fd
;
816 enum lttcomm_return_code code
;
817 struct lttng_poll_event events
;
819 tracepoint(sessiond_th_kcon_start
);
821 DBG("[thread] Manage kconsumerd started");
823 ret
= lttcomm_listen_unix_sock(kconsumerd_err_sock
);
829 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
830 * Nothing more will be added to this poll set.
832 ret
= create_thread_poll_set(&events
, 2);
837 ret
= lttng_poll_add(&events
, kconsumerd_err_sock
, LPOLLIN
| LPOLLRDHUP
);
842 nb_fd
= LTTNG_POLL_GETNB(&events
);
844 tracepoint(sessiond_th_kcon_poll
);
846 /* Inifinite blocking call, waiting for transmission */
847 ret
= lttng_poll_wait(&events
, -1);
852 for (i
= 0; i
< nb_fd
; i
++) {
853 /* Fetch once the poll data */
854 revents
= LTTNG_POLL_GETEV(&events
, i
);
855 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
857 /* Thread quit pipe has been closed. Killing thread. */
858 ret
= check_thread_quit_pipe(pollfd
, revents
);
863 /* Event on the registration socket */
864 if (pollfd
== kconsumerd_err_sock
) {
865 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
866 ERR("Kconsumerd err socket poll error");
872 sock
= lttcomm_accept_unix_sock(kconsumerd_err_sock
);
877 /* Getting status code from kconsumerd */
878 ret
= lttcomm_recv_unix_sock(sock
, &code
,
879 sizeof(enum lttcomm_return_code
));
884 if (code
== KCONSUMERD_COMMAND_SOCK_READY
) {
885 kconsumerd_cmd_sock
=
886 lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path
);
887 if (kconsumerd_cmd_sock
< 0) {
888 sem_post(&kconsumerd_sem
);
889 perror("kconsumerd connect");
892 /* Signal condition to tell that the kconsumerd is ready */
893 sem_post(&kconsumerd_sem
);
894 DBG("Kconsumerd command socket ready");
896 DBG("Kconsumerd error when waiting for SOCK_READY : %s",
897 lttcomm_get_readable_code(-code
));
901 /* Remove the kconsumerd error sock since we've established a connexion */
902 ret
= lttng_poll_del(&events
, kconsumerd_err_sock
);
907 ret
= lttng_poll_add(&events
, sock
, LPOLLIN
| LPOLLRDHUP
);
912 /* Update number of fd */
913 nb_fd
= LTTNG_POLL_GETNB(&events
);
915 /* Inifinite blocking call, waiting for transmission */
916 ret
= lttng_poll_wait(&events
, -1);
921 for (i
= 0; i
< nb_fd
; i
++) {
922 /* Fetch once the poll data */
923 revents
= LTTNG_POLL_GETEV(&events
, i
);
924 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
926 /* Thread quit pipe has been closed. Killing thread. */
927 ret
= check_thread_quit_pipe(pollfd
, revents
);
932 /* Event on the kconsumerd socket */
933 if (pollfd
== sock
) {
934 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
935 ERR("Kconsumerd err socket second poll error");
941 /* Wait for any kconsumerd error */
942 ret
= lttcomm_recv_unix_sock(sock
, &code
,
943 sizeof(enum lttcomm_return_code
));
945 ERR("Kconsumerd closed the command socket");
949 ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code
));
952 DBG("Kconsumerd thread dying");
953 close(kconsumerd_err_sock
);
954 close(kconsumerd_cmd_sock
);
957 unlink(kconsumerd_err_unix_sock_path
);
958 unlink(kconsumerd_cmd_unix_sock_path
);
961 lttng_poll_clean(&events
);
967 * This thread manage application communication.
969 static void *thread_manage_apps(void *data
)
972 uint32_t revents
, nb_fd
;
973 struct ust_command ust_cmd
;
974 struct lttng_poll_event events
;
976 tracepoint(sessiond_th_apps_start
);
978 DBG("[thread] Manage application started");
980 ret
= create_thread_poll_set(&events
, 2);
985 ret
= lttng_poll_add(&events
, apps_cmd_pipe
[0], LPOLLIN
| LPOLLRDHUP
);
991 /* Zeroed the events structure */
992 lttng_poll_reset(&events
);
994 nb_fd
= LTTNG_POLL_GETNB(&events
);
996 DBG("Apps thread polling on %d fds", nb_fd
);
998 tracepoint(sessiond_th_apps_poll
);
1000 /* Inifinite blocking call, waiting for transmission */
1001 ret
= lttng_poll_wait(&events
, -1);
1006 for (i
= 0; i
< nb_fd
; i
++) {
1007 /* Fetch once the poll data */
1008 revents
= LTTNG_POLL_GETEV(&events
, i
);
1009 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
1011 /* Thread quit pipe has been closed. Killing thread. */
1012 ret
= check_thread_quit_pipe(pollfd
, revents
);
1017 /* Inspect the apps cmd pipe */
1018 if (pollfd
== apps_cmd_pipe
[0]) {
1019 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1020 ERR("Apps command pipe error");
1022 } else if (revents
& LPOLLIN
) {
1023 tracepoint(ust_register_read_start
);
1025 ret
= read(apps_cmd_pipe
[0], &ust_cmd
, sizeof(ust_cmd
));
1026 if (ret
< 0 || ret
< sizeof(ust_cmd
)) {
1027 perror("read apps cmd pipe");
1030 tracepoint(ust_register_read_stop
);
1032 tracepoint(ust_register_add_start
);
1033 /* Register applicaton to the session daemon */
1034 ret
= ust_app_register(&ust_cmd
.reg_msg
,
1037 /* Only critical ENOMEM error can be returned here */
1040 tracepoint(ust_register_add_stop
);
1042 tracepoint(ust_register_done_start
);
1043 ret
= ustctl_register_done(ust_cmd
.sock
);
1046 * If the registration is not possible, we simply
1047 * unregister the apps and continue
1049 ust_app_unregister(ust_cmd
.sock
);
1052 * We just need here to monitor the close of the UST
1053 * socket and poll set monitor those by default.
1055 ret
= lttng_poll_add(&events
, ust_cmd
.sock
, 0);
1060 DBG("Apps with sock %d added to poll set",
1063 tracepoint(ust_register_done_stop
);
1068 * At this point, we know that a registered application made
1069 * the event at poll_wait.
1071 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1072 /* Removing from the poll set */
1073 ret
= lttng_poll_del(&events
, pollfd
);
1079 ust_app_unregister(pollfd
);
1087 DBG("Application communication apps dying");
1088 close(apps_cmd_pipe
[0]);
1089 close(apps_cmd_pipe
[1]);
1091 lttng_poll_clean(&events
);
1097 * Dispatch request from the registration threads to the application
1098 * communication thread.
1100 static void *thread_dispatch_ust_registration(void *data
)
1103 struct cds_wfq_node
*node
;
1104 struct ust_command
*ust_cmd
= NULL
;
1106 tracepoint(sessiond_th_dispatch_start
);
1108 DBG("[thread] Dispatch UST command started");
1110 while (!dispatch_thread_exit
) {
1111 /* Atomically prepare the queue futex */
1112 futex_nto1_prepare(&ust_cmd_queue
.futex
);
1115 tracepoint(sessiond_th_dispatch_block
);
1117 /* Dequeue command for registration */
1118 node
= cds_wfq_dequeue_blocking(&ust_cmd_queue
.queue
);
1120 DBG("Waked up but nothing in the UST command queue");
1121 /* Continue thread execution */
1125 tracepoint(ust_dispatch_register_start
);
1127 ust_cmd
= caa_container_of(node
, struct ust_command
, node
);
1129 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1130 " gid:%d sock:%d name:%s (version %d.%d)",
1131 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1132 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1133 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1134 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1136 * Inform apps thread of the new application registration. This
1137 * call is blocking so we can be assured that the data will be read
1138 * at some point in time or wait to the end of the world :)
1140 ret
= write(apps_cmd_pipe
[1], ust_cmd
,
1141 sizeof(struct ust_command
));
1143 perror("write apps cmd pipe");
1144 if (errno
== EBADF
) {
1146 * We can't inform the application thread to process
1147 * registration. We will exit or else application
1148 * registration will not occur and tracing will never
1155 } while (node
!= NULL
);
1157 tracepoint(ust_dispatch_register_stop
);
1159 /* Futex wait on queue. Blocking call on futex() */
1160 futex_nto1_wait(&ust_cmd_queue
.futex
);
1164 DBG("Dispatch thread dying");
1169 * This thread manage application registration.
1171 static void *thread_registration_apps(void *data
)
1173 int sock
= 0, i
, ret
, pollfd
;
1174 uint32_t revents
, nb_fd
;
1175 struct lttng_poll_event events
;
1177 * Get allocated in this thread, enqueued to a global queue, dequeued and
1178 * freed in the manage apps thread.
1180 struct ust_command
*ust_cmd
= NULL
;
1182 tracepoint(sessiond_th_reg_start
);
1184 DBG("[thread] Manage application registration started");
1186 ret
= lttcomm_listen_unix_sock(apps_sock
);
1192 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1193 * more will be added to this poll set.
1195 ret
= create_thread_poll_set(&events
, 2);
1200 /* Add the application registration socket */
1201 ret
= lttng_poll_add(&events
, apps_sock
, LPOLLIN
| LPOLLRDHUP
);
1206 /* Notify all applications to register */
1207 ret
= notify_ust_apps(1);
1209 ERR("Failed to notify applications or create the wait shared memory.\n"
1210 "Execution continues but there might be problem for already\n"
1211 "running applications that wishes to register.");
1215 DBG("Accepting application registration");
1217 tracepoint(sessiond_th_reg_poll
);
1219 nb_fd
= LTTNG_POLL_GETNB(&events
);
1221 /* Inifinite blocking call, waiting for transmission */
1222 ret
= lttng_poll_wait(&events
, -1);
1227 for (i
= 0; i
< nb_fd
; i
++) {
1228 /* Fetch once the poll data */
1229 revents
= LTTNG_POLL_GETEV(&events
, i
);
1230 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
1232 /* Thread quit pipe has been closed. Killing thread. */
1233 ret
= check_thread_quit_pipe(pollfd
, revents
);
1238 /* Event on the registration socket */
1239 if (pollfd
== apps_sock
) {
1240 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1241 ERR("Register apps socket poll error");
1243 } else if (revents
& LPOLLIN
) {
1244 /* Registration starts here. Recording cycles */
1245 tracepoint(ust_register_start
);
1247 sock
= lttcomm_accept_unix_sock(apps_sock
);
1252 /* Create UST registration command for enqueuing */
1253 ust_cmd
= malloc(sizeof(struct ust_command
));
1254 if (ust_cmd
== NULL
) {
1255 perror("ust command malloc");
1260 * Using message-based transmissions to ensure we don't
1261 * have to deal with partially received messages.
1263 ret
= lttcomm_recv_unix_sock(sock
, &ust_cmd
->reg_msg
,
1264 sizeof(struct ust_register_msg
));
1265 if (ret
< 0 || ret
< sizeof(struct ust_register_msg
)) {
1267 perror("lttcomm_recv_unix_sock register apps");
1269 ERR("Wrong size received on apps register");
1276 ust_cmd
->sock
= sock
;
1278 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1279 " gid:%d sock:%d name:%s (version %d.%d)",
1280 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1281 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1282 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1283 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1286 * Lock free enqueue the registration request. The red pill
1287 * has been taken! This apps will be part of the *system*.
1289 cds_wfq_enqueue(&ust_cmd_queue
.queue
, &ust_cmd
->node
);
1292 * Wake the registration queue futex. Implicit memory
1293 * barrier with the exchange in cds_wfq_enqueue.
1295 futex_nto1_wake(&ust_cmd_queue
.futex
);
1297 tracepoint(ust_register_stop
);
1304 DBG("UST Registration thread dying");
1306 /* Notify that the registration thread is gone */
1311 unlink(apps_unix_sock_path
);
1313 lttng_poll_clean(&events
);
1319 * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
1320 * exec or it will fails.
1322 static int spawn_kconsumerd_thread(void)
1326 /* Setup semaphore */
1327 sem_init(&kconsumerd_sem
, 0, 0);
1329 ret
= pthread_create(&kconsumerd_thread
, NULL
,
1330 thread_manage_kconsumerd
, (void *) NULL
);
1332 perror("pthread_create kconsumerd");
1336 /* Wait for the kconsumerd thread to be ready */
1337 sem_wait(&kconsumerd_sem
);
1339 if (kconsumerd_pid
== 0) {
1340 ERR("Kconsumerd did not start");
1347 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1352 * Join kernel consumer thread
1354 static int join_kconsumerd_thread(void)
1359 if (kconsumerd_pid
!= 0) {
1360 ret
= kill(kconsumerd_pid
, SIGTERM
);
1362 ERR("Error killing kconsumerd");
1365 return pthread_join(kconsumerd_thread
, &status
);
1372 * Fork and exec a kernel consumer daemon (kconsumerd).
1374 * Return pid if successful else -1.
1376 static pid_t
spawn_kconsumerd(void)
1380 const char *verbosity
;
1382 DBG("Spawning kconsumerd");
1389 if (opt_verbose
> 1 || opt_verbose_kconsumerd
) {
1390 verbosity
= "--verbose";
1392 verbosity
= "--quiet";
1394 execl(INSTALL_BIN_PATH
"/ltt-kconsumerd",
1395 "ltt-kconsumerd", verbosity
, NULL
);
1397 perror("kernel start consumer exec");
1400 } else if (pid
> 0) {
1404 perror("kernel start consumer fork");
1414 * Spawn the kconsumerd daemon and session daemon thread.
1416 static int start_kconsumerd(void)
1420 pthread_mutex_lock(&kconsumerd_pid_mutex
);
1421 if (kconsumerd_pid
!= 0) {
1422 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1426 ret
= spawn_kconsumerd();
1428 ERR("Spawning kconsumerd failed");
1429 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1430 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1434 /* Setting up the global kconsumerd_pid */
1435 kconsumerd_pid
= ret
;
1436 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1438 DBG("Kconsumerd pid %d", ret
);
1440 DBG("Spawning kconsumerd thread");
1441 ret
= spawn_kconsumerd_thread();
1443 ERR("Fatal error spawning kconsumerd thread");
1455 * modprobe_kernel_modules
1457 static int modprobe_kernel_modules(void)
1462 for (i
= 0; i
< ARRAY_SIZE(kernel_modules_list
); i
++) {
1463 ret
= snprintf(modprobe
, sizeof(modprobe
),
1464 "/sbin/modprobe %s%s",
1465 kernel_modules_list
[i
].required
? "" : "--quiet ",
1466 kernel_modules_list
[i
].name
);
1468 perror("snprintf modprobe");
1471 modprobe
[sizeof(modprobe
) - 1] = '\0';
1472 ret
= system(modprobe
);
1474 ERR("Unable to launch modprobe for module %s",
1475 kernel_modules_list
[i
].name
);
1476 } else if (kernel_modules_list
[i
].required
1477 && WEXITSTATUS(ret
) != 0) {
1478 ERR("Unable to load module %s",
1479 kernel_modules_list
[i
].name
);
1481 DBG("Modprobe successfully %s",
1482 kernel_modules_list
[i
].name
);
1493 static int mount_debugfs(char *path
)
1496 char *type
= "debugfs";
1498 ret
= mkdir_recursive(path
, S_IRWXU
| S_IRWXG
, geteuid(), getegid());
1500 PERROR("Cannot create debugfs path");
1504 ret
= mount(type
, path
, type
, 0, NULL
);
1506 PERROR("Cannot mount debugfs");
1510 DBG("Mounted debugfs successfully at %s", path
);
1517 * Setup necessary data for kernel tracer action.
1519 static void init_kernel_tracer(void)
1522 char *proc_mounts
= "/proc/mounts";
1524 char *debugfs_path
= NULL
, *lttng_path
= NULL
;
1527 /* Detect debugfs */
1528 fp
= fopen(proc_mounts
, "r");
1530 ERR("Unable to probe %s", proc_mounts
);
1534 while (fgets(line
, sizeof(line
), fp
) != NULL
) {
1535 if (strstr(line
, "debugfs") != NULL
) {
1536 /* Remove first string */
1538 /* Dup string here so we can reuse line later on */
1539 debugfs_path
= strdup(strtok(NULL
, " "));
1540 DBG("Got debugfs path : %s", debugfs_path
);
1547 /* Mount debugfs if needded */
1548 if (debugfs_path
== NULL
) {
1549 ret
= asprintf(&debugfs_path
, "/mnt/debugfs");
1551 perror("asprintf debugfs path");
1554 ret
= mount_debugfs(debugfs_path
);
1556 perror("Cannot mount debugfs");
1561 /* Modprobe lttng kernel modules */
1562 ret
= modprobe_kernel_modules();
1567 /* Setup lttng kernel path */
1568 ret
= asprintf(<tng_path
, "%s/lttng", debugfs_path
);
1570 perror("asprintf lttng path");
1574 /* Open debugfs lttng */
1575 kernel_tracer_fd
= open(lttng_path
, O_RDWR
);
1576 if (kernel_tracer_fd
< 0) {
1577 DBG("Failed to open %s", lttng_path
);
1583 DBG("Kernel tracer fd %d", kernel_tracer_fd
);
1593 WARN("No kernel tracer available");
1594 kernel_tracer_fd
= 0;
1599 * Init tracing by creating trace directory and sending fds kernel consumer.
1601 static int init_kernel_tracing(struct ltt_kernel_session
*session
)
1605 if (session
->kconsumer_fds_sent
== 0) {
1607 * Assign default kernel consumer socket if no consumer assigned to the
1608 * kernel session. At this point, it's NOT suppose to be 0 but this is
1609 * an extra security check.
1611 if (session
->consumer_fd
== 0) {
1612 session
->consumer_fd
= kconsumerd_cmd_sock
;
1615 ret
= send_kconsumerd_fds(session
);
1617 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1621 session
->kconsumer_fds_sent
= 1;
1629 * Create an UST session and add it to the session ust list.
1631 static int create_ust_session(struct ltt_session
*session
,
1632 struct lttng_domain
*domain
)
1635 struct ltt_ust_session
*lus
= NULL
;
1636 struct ust_app
*app
;
1638 switch (domain
->type
) {
1639 case LTTNG_DOMAIN_UST_PID
:
1640 app
= ust_app_get_by_pid(domain
->attr
.pid
);
1642 ret
= LTTCOMM_APP_NOT_FOUND
;
1647 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
1651 DBG("Creating UST session");
1653 lus
= trace_ust_create_session(session
->path
, domain
->attr
.pid
, domain
);
1655 ret
= LTTCOMM_UST_SESS_FAIL
;
1659 ret
= mkdir_recursive(lus
->path
, S_IRWXU
| S_IRWXG
,
1660 geteuid(), allowed_group());
1662 if (ret
!= -EEXIST
) {
1663 ERR("Trace directory creation error");
1664 ret
= LTTCOMM_UST_SESS_FAIL
;
1669 /* Create session on the UST tracer */
1670 ret
= ustctl_create_session(app
->sock
, lus
);
1672 ret
= LTTCOMM_UST_SESS_FAIL
;
1676 cds_list_add(&lus
->list
, &session
->ust_session_list
.head
);
1677 session
->ust_session_list
.count
++;
1687 * Create a kernel tracer session then create the default channel.
1689 static int create_kernel_session(struct ltt_session
*session
)
1693 DBG("Creating kernel session");
1695 ret
= kernel_create_session(session
, kernel_tracer_fd
);
1697 ret
= LTTCOMM_KERN_SESS_FAIL
;
1701 /* Set kernel consumer socket fd */
1702 if (kconsumerd_cmd_sock
) {
1703 session
->kernel_session
->consumer_fd
= kconsumerd_cmd_sock
;
1706 ret
= mkdir_recursive(session
->kernel_session
->trace_path
,
1707 S_IRWXU
| S_IRWXG
, geteuid(), allowed_group());
1709 if (ret
!= -EEXIST
) {
1710 ERR("Trace directory creation error");
1720 * Using the session list, filled a lttng_session array to send back to the
1721 * client for session listing.
1723 * The session list lock MUST be acquired before calling this function. Use
1724 * session_lock_list() and session_unlock_list().
1726 static void list_lttng_sessions(struct lttng_session
*sessions
)
1729 struct ltt_session
*session
;
1731 DBG("Getting all available session");
1733 * Iterate over session list and append data after the control struct in
1736 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
1737 strncpy(sessions
[i
].path
, session
->path
, PATH_MAX
);
1738 sessions
[i
].path
[PATH_MAX
- 1] = '\0';
1739 strncpy(sessions
[i
].name
, session
->name
, NAME_MAX
);
1740 sessions
[i
].name
[NAME_MAX
- 1] = '\0';
1746 * Fill lttng_channel array of all channels.
1748 static void list_lttng_channels(struct ltt_session
*session
,
1749 struct lttng_channel
*channels
)
1752 struct ltt_kernel_channel
*kchan
;
1754 DBG("Listing channels for session %s", session
->name
);
1756 /* Kernel channels */
1757 if (session
->kernel_session
!= NULL
) {
1758 cds_list_for_each_entry(kchan
,
1759 &session
->kernel_session
->channel_list
.head
, list
) {
1760 /* Copy lttng_channel struct to array */
1761 memcpy(&channels
[i
], kchan
->channel
, sizeof(struct lttng_channel
));
1762 channels
[i
].enabled
= kchan
->enabled
;
1767 /* TODO: Missing UST listing */
1771 * Fill lttng_event array of all events in the channel.
1773 static void list_lttng_events(struct ltt_kernel_channel
*kchan
,
1774 struct lttng_event
*events
)
1777 * TODO: This is ONLY kernel. Need UST support.
1780 struct ltt_kernel_event
*event
;
1782 DBG("Listing events for channel %s", kchan
->channel
->name
);
1784 /* Kernel channels */
1785 cds_list_for_each_entry(event
, &kchan
->events_list
.head
, list
) {
1786 strncpy(events
[i
].name
, event
->event
->name
, LTTNG_SYMBOL_NAME_LEN
);
1787 events
[i
].name
[LTTNG_SYMBOL_NAME_LEN
- 1] = '\0';
1788 events
[i
].enabled
= event
->enabled
;
1789 switch (event
->event
->instrumentation
) {
1790 case LTTNG_KERNEL_TRACEPOINT
:
1791 events
[i
].type
= LTTNG_EVENT_TRACEPOINT
;
1793 case LTTNG_KERNEL_KPROBE
:
1794 case LTTNG_KERNEL_KRETPROBE
:
1795 events
[i
].type
= LTTNG_EVENT_PROBE
;
1796 memcpy(&events
[i
].attr
.probe
, &event
->event
->u
.kprobe
,
1797 sizeof(struct lttng_kernel_kprobe
));
1799 case LTTNG_KERNEL_FUNCTION
:
1800 events
[i
].type
= LTTNG_EVENT_FUNCTION
;
1801 memcpy(&events
[i
].attr
.ftrace
, &event
->event
->u
.ftrace
,
1802 sizeof(struct lttng_kernel_function
));
1804 case LTTNG_KERNEL_NOOP
:
1805 events
[i
].type
= LTTNG_EVENT_NOOP
;
1807 case LTTNG_KERNEL_SYSCALL
:
1808 events
[i
].type
= LTTNG_EVENT_SYSCALL
;
1810 case LTTNG_KERNEL_ALL
:
1819 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1821 static int cmd_disable_channel(struct ltt_session
*session
,
1822 int domain
, char *channel_name
)
1827 case LTTNG_DOMAIN_KERNEL
:
1828 ret
= channel_kernel_disable(session
->kernel_session
,
1830 if (ret
!= LTTCOMM_OK
) {
1834 kernel_wait_quiescent(kernel_tracer_fd
);
1836 case LTTNG_DOMAIN_UST_PID
:
1839 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
1850 * Copy channel from attributes and set it in the application channel list.
1852 static int copy_ust_channel_to_app(struct ltt_ust_session
*usess
,
1853 struct lttng_channel
*attr
, struct ust_app
*app
)
1856 struct ltt_ust_channel
*uchan
, *new_chan
;
1858 uchan
= trace_ust_get_channel_by_name(attr
->name
, usess
);
1859 if (uchan
== NULL
) {
1860 ret
= LTTCOMM_FATAL
;
1864 new_chan
= trace_ust_create_channel(attr
, usess
->path
);
1865 if (new_chan
== NULL
) {
1866 PERROR("malloc ltt_ust_channel");
1867 ret
= LTTCOMM_FATAL
;
1871 ret
= channel_ust_copy(new_chan
, uchan
);
1873 ret
= LTTCOMM_FATAL
;
1877 /* Add channel to the ust app channel list */
1878 cds_list_add(&new_chan
->list
, &app
->channels
.head
);
1879 app
->channels
.count
++;
1886 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1888 static int cmd_enable_channel(struct ltt_session
*session
,
1889 struct lttng_domain
*domain
, struct lttng_channel
*attr
)
1893 switch (domain
->type
) {
1894 case LTTNG_DOMAIN_KERNEL
:
1896 struct ltt_kernel_channel
*kchan
;
1898 kchan
= trace_kernel_get_channel_by_name(attr
->name
,
1899 session
->kernel_session
);
1900 if (kchan
== NULL
) {
1901 ret
= channel_kernel_create(session
->kernel_session
,
1902 attr
, kernel_poll_pipe
[1]);
1904 ret
= channel_kernel_enable(session
->kernel_session
, kchan
);
1907 if (ret
!= LTTCOMM_OK
) {
1911 kernel_wait_quiescent(kernel_tracer_fd
);
1914 case LTTNG_DOMAIN_UST_PID
:
1917 struct ltt_ust_channel
*uchan
;
1918 struct ltt_ust_session
*usess
;
1919 struct ust_app
*app
;
1921 usess
= trace_ust_get_session_by_pid(&session
->ust_session_list
,
1923 if (usess
== NULL
) {
1924 ret
= LTTCOMM_UST_CHAN_NOT_FOUND
;
1928 app
= ust_app_get_by_pid(domain
->attr
.pid
);
1930 ret
= LTTCOMM_APP_NOT_FOUND
;
1935 uchan
= trace_ust_get_channel_by_name(attr
->name
, usess
);
1936 if (uchan
== NULL
) {
1937 ret
= channel_ust_create(usess
, attr
, sock
);
1939 ret
= channel_ust_enable(usess
, uchan
, sock
);
1942 if (ret
!= LTTCOMM_OK
) {
1946 ret
= copy_ust_channel_to_app(usess
, attr
, app
);
1947 if (ret
!= LTTCOMM_OK
) {
1951 DBG("UST channel %s created for app sock %d with pid %d",
1952 attr
->name
, app
->sock
, domain
->attr
.pid
);
1956 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
1967 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1969 static int cmd_disable_event(struct ltt_session
*session
, int domain
,
1970 char *channel_name
, char *event_name
)
1973 struct ltt_kernel_channel
*kchan
;
1976 case LTTNG_DOMAIN_KERNEL
:
1977 kchan
= trace_kernel_get_channel_by_name(channel_name
,
1978 session
->kernel_session
);
1979 if (kchan
== NULL
) {
1980 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
1984 ret
= event_kernel_disable_tracepoint(session
->kernel_session
, kchan
, event_name
);
1985 if (ret
!= LTTCOMM_OK
) {
1989 kernel_wait_quiescent(kernel_tracer_fd
);
1992 /* TODO: Userspace tracing */
1993 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2004 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2006 static int cmd_disable_event_all(struct ltt_session
*session
, int domain
,
2010 struct ltt_kernel_channel
*kchan
;
2013 case LTTNG_DOMAIN_KERNEL
:
2014 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2015 session
->kernel_session
);
2016 if (kchan
== NULL
) {
2017 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
2021 ret
= event_kernel_disable_all(session
->kernel_session
, kchan
);
2022 if (ret
!= LTTCOMM_OK
) {
2026 kernel_wait_quiescent(kernel_tracer_fd
);
2029 /* TODO: Userspace tracing */
2030 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2041 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2043 static int cmd_add_context(struct ltt_session
*session
, int domain
,
2044 char *channel_name
, char *event_name
, struct lttng_event_context
*ctx
)
2049 case LTTNG_DOMAIN_KERNEL
:
2050 /* Add kernel context to kernel tracer */
2051 ret
= context_kernel_add(session
->kernel_session
, ctx
,
2052 event_name
, channel_name
);
2053 if (ret
!= LTTCOMM_OK
) {
2059 /* TODO: Userspace tracing */
2060 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2071 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2073 static int cmd_enable_event(struct ltt_session
*session
, int domain
,
2074 char *channel_name
, struct lttng_event
*event
)
2077 struct ltt_kernel_channel
*kchan
;
2080 case LTTNG_DOMAIN_KERNEL
:
2081 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2082 session
->kernel_session
);
2083 if (kchan
== NULL
) {
2084 /* This call will notify the kernel thread */
2085 ret
= channel_kernel_create(session
->kernel_session
,
2086 NULL
, kernel_poll_pipe
[1]);
2087 if (ret
!= LTTCOMM_OK
) {
2092 /* Get the newly created kernel channel pointer */
2093 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2094 session
->kernel_session
);
2095 if (kchan
== NULL
) {
2096 /* This sould not happen... */
2097 ret
= LTTCOMM_FATAL
;
2101 ret
= event_kernel_enable_tracepoint(session
->kernel_session
, kchan
, event
);
2102 if (ret
!= LTTCOMM_OK
) {
2106 kernel_wait_quiescent(kernel_tracer_fd
);
2109 /* TODO: Userspace tracing */
2110 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2121 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2123 static int cmd_enable_event_all(struct ltt_session
*session
, int domain
,
2124 char *channel_name
, int event_type
)
2127 struct ltt_kernel_channel
*kchan
;
2130 case LTTNG_DOMAIN_KERNEL
:
2131 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2132 session
->kernel_session
);
2133 if (kchan
== NULL
) {
2134 /* This call will notify the kernel thread */
2135 ret
= channel_kernel_create(session
->kernel_session
, NULL
,
2136 kernel_poll_pipe
[1]);
2137 if (ret
!= LTTCOMM_OK
) {
2142 /* Get the newly created kernel channel pointer */
2143 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2144 session
->kernel_session
);
2145 if (kchan
== NULL
) {
2146 /* This sould not happen... */
2147 ret
= LTTCOMM_FATAL
;
2151 switch (event_type
) {
2152 case LTTNG_KERNEL_SYSCALL
:
2153 ret
= event_kernel_enable_all_syscalls(session
->kernel_session
,
2154 kchan
, kernel_tracer_fd
);
2156 case LTTNG_KERNEL_TRACEPOINT
:
2158 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2159 * events already registered to the channel.
2161 ret
= event_kernel_enable_all_tracepoints(session
->kernel_session
,
2162 kchan
, kernel_tracer_fd
);
2164 case LTTNG_KERNEL_ALL
:
2165 /* Enable syscalls and tracepoints */
2166 ret
= event_kernel_enable_all(session
->kernel_session
,
2167 kchan
, kernel_tracer_fd
);
2170 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2173 if (ret
!= LTTCOMM_OK
) {
2177 kernel_wait_quiescent(kernel_tracer_fd
);
2180 /* TODO: Userspace tracing */
2181 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2192 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2194 static ssize_t
cmd_list_tracepoints(int domain
, struct lttng_event
**events
)
2197 ssize_t nb_events
= 0;
2200 case LTTNG_DOMAIN_KERNEL
:
2201 nb_events
= kernel_list_events(kernel_tracer_fd
, events
);
2202 if (nb_events
< 0) {
2203 ret
= LTTCOMM_KERN_LIST_FAIL
;
2208 /* TODO: Userspace listing */
2209 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2216 /* Return negative value to differentiate return code */
2221 * Command LTTNG_START_TRACE processed by the client thread.
2223 static int cmd_start_trace(struct ltt_session
*session
)
2226 struct ltt_kernel_channel
*kchan
;
2227 struct ltt_kernel_session
*ksession
;
2230 ksession
= session
->kernel_session
;
2232 /* Kernel tracing */
2233 if (ksession
!= NULL
) {
2234 /* Open kernel metadata */
2235 if (ksession
->metadata
== NULL
) {
2236 ret
= kernel_open_metadata(ksession
, ksession
->trace_path
);
2238 ret
= LTTCOMM_KERN_META_FAIL
;
2243 /* Open kernel metadata stream */
2244 if (ksession
->metadata_stream_fd
== 0) {
2245 ret
= kernel_open_metadata_stream(ksession
);
2247 ERR("Kernel create metadata stream failed");
2248 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2253 /* For each channel */
2254 cds_list_for_each_entry(kchan
, &ksession
->channel_list
.head
, list
) {
2255 if (kchan
->stream_count
== 0) {
2256 ret
= kernel_open_channel_stream(kchan
);
2258 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2261 /* Update the stream global counter */
2262 ksession
->stream_count_global
+= ret
;
2266 /* Setup kernel consumer socket and send fds to it */
2267 ret
= init_kernel_tracing(ksession
);
2269 ret
= LTTCOMM_KERN_START_FAIL
;
2273 /* This start the kernel tracing */
2274 ret
= kernel_start_session(ksession
);
2276 ret
= LTTCOMM_KERN_START_FAIL
;
2280 /* Quiescent wait after starting trace */
2281 kernel_wait_quiescent(kernel_tracer_fd
);
2284 /* TODO: Start all UST traces */
2293 * Command LTTNG_STOP_TRACE processed by the client thread.
2295 static int cmd_stop_trace(struct ltt_session
*session
)
2298 struct ltt_kernel_channel
*kchan
;
2299 struct ltt_kernel_session
*ksession
;
2302 ksession
= session
->kernel_session
;
2305 if (ksession
!= NULL
) {
2306 DBG("Stop kernel tracing");
2308 /* Flush all buffers before stopping */
2309 ret
= kernel_metadata_flush_buffer(ksession
->metadata_stream_fd
);
2311 ERR("Kernel metadata flush failed");
2314 cds_list_for_each_entry(kchan
, &ksession
->channel_list
.head
, list
) {
2315 ret
= kernel_flush_buffer(kchan
);
2317 ERR("Kernel flush buffer error");
2321 ret
= kernel_stop_session(ksession
);
2323 ret
= LTTCOMM_KERN_STOP_FAIL
;
2327 kernel_wait_quiescent(kernel_tracer_fd
);
2330 /* TODO : User-space tracer */
2339 * Command LTTNG_CREATE_SESSION processed by the client thread.
2341 static int cmd_create_session(char *name
, char *path
)
2345 ret
= session_create(name
, path
);
2346 if (ret
!= LTTCOMM_OK
) {
2357 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2359 static int cmd_destroy_session(struct ltt_session
*session
, char *name
)
2363 /* Clean kernel session teardown */
2364 teardown_kernel_session(session
);
2367 * Must notify the kernel thread here to update it's poll setin order
2368 * to remove the channel(s)' fd just destroyed.
2370 ret
= notify_thread_pipe(kernel_poll_pipe
[1]);
2372 perror("write kernel poll pipe");
2375 ret
= session_destroy(session
);
2381 * Command LTTNG_CALIBRATE processed by the client thread.
2383 static int cmd_calibrate(int domain
, struct lttng_calibrate
*calibrate
)
2388 case LTTNG_DOMAIN_KERNEL
:
2390 struct lttng_kernel_calibrate kcalibrate
;
2392 kcalibrate
.type
= calibrate
->type
;
2393 ret
= kernel_calibrate(kernel_tracer_fd
, &kcalibrate
);
2395 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2401 /* TODO: Userspace tracing */
2402 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2413 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2415 static int cmd_register_consumer(struct ltt_session
*session
, int domain
,
2421 case LTTNG_DOMAIN_KERNEL
:
2422 /* Can't register a consumer if there is already one */
2423 if (session
->kernel_session
->consumer_fd
!= 0) {
2424 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
2428 sock
= lttcomm_connect_unix_sock(sock_path
);
2430 ret
= LTTCOMM_CONNECT_FAIL
;
2434 session
->kernel_session
->consumer_fd
= sock
;
2437 /* TODO: Userspace tracing */
2438 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2449 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2451 static ssize_t
cmd_list_domains(struct ltt_session
*session
,
2452 struct lttng_domain
**domains
)
2457 if (session
->kernel_session
!= NULL
) {
2461 nb_dom
+= session
->ust_session_list
.count
;
2463 *domains
= malloc(nb_dom
* sizeof(struct lttng_domain
));
2464 if (*domains
== NULL
) {
2465 ret
= -LTTCOMM_FATAL
;
2469 (*domains
)[0].type
= LTTNG_DOMAIN_KERNEL
;
2471 /* TODO: User-space tracer domain support */
2480 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2482 static ssize_t
cmd_list_channels(struct ltt_session
*session
,
2483 struct lttng_channel
**channels
)
2486 ssize_t nb_chan
= 0;
2488 if (session
->kernel_session
!= NULL
) {
2489 nb_chan
+= session
->kernel_session
->channel_count
;
2492 *channels
= malloc(nb_chan
* sizeof(struct lttng_channel
));
2493 if (*channels
== NULL
) {
2494 ret
= -LTTCOMM_FATAL
;
2498 list_lttng_channels(session
, *channels
);
2507 * Command LTTNG_LIST_EVENTS processed by the client thread.
2509 static ssize_t
cmd_list_events(struct ltt_session
*session
,
2510 char *channel_name
, struct lttng_event
**events
)
2513 ssize_t nb_event
= 0;
2514 struct ltt_kernel_channel
*kchan
= NULL
;
2516 if (session
->kernel_session
!= NULL
) {
2517 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2518 session
->kernel_session
);
2519 if (kchan
== NULL
) {
2520 ret
= -LTTCOMM_KERN_CHAN_NOT_FOUND
;
2523 nb_event
+= kchan
->event_count
;
2526 *events
= malloc(nb_event
* sizeof(struct lttng_event
));
2527 if (*events
== NULL
) {
2528 ret
= -LTTCOMM_FATAL
;
2532 list_lttng_events(kchan
, *events
);
2534 /* TODO: User-space tracer support */
2543 * Process the command requested by the lttng client within the command
2544 * context structure. This function make sure that the return structure (llm)
2545 * is set and ready for transmission before returning.
2547 * Return any error encountered or 0 for success.
2549 static int process_client_msg(struct command_ctx
*cmd_ctx
)
2551 int ret
= LTTCOMM_OK
;
2552 int need_tracing_session
= 1;
2554 DBG("Processing client command %d", cmd_ctx
->lsm
->cmd_type
);
2557 * Check for command that don't needs to allocate a returned payload. We do
2558 * this here so we don't have to make the call for no payload at each
2561 switch(cmd_ctx
->lsm
->cmd_type
) {
2562 case LTTNG_LIST_SESSIONS
:
2563 case LTTNG_LIST_TRACEPOINTS
:
2564 case LTTNG_LIST_DOMAINS
:
2565 case LTTNG_LIST_CHANNELS
:
2566 case LTTNG_LIST_EVENTS
:
2569 /* Setup lttng message with no payload */
2570 ret
= setup_lttng_msg(cmd_ctx
, 0);
2572 /* This label does not try to unlock the session */
2573 goto init_setup_error
;
2577 /* Commands that DO NOT need a session. */
2578 switch (cmd_ctx
->lsm
->cmd_type
) {
2579 case LTTNG_CALIBRATE
:
2580 case LTTNG_CREATE_SESSION
:
2581 case LTTNG_LIST_SESSIONS
:
2582 case LTTNG_LIST_TRACEPOINTS
:
2583 need_tracing_session
= 0;
2586 DBG("Getting session %s by name", cmd_ctx
->lsm
->session
.name
);
2587 cmd_ctx
->session
= session_find_by_name(cmd_ctx
->lsm
->session
.name
);
2588 if (cmd_ctx
->session
== NULL
) {
2589 if (cmd_ctx
->lsm
->session
.name
!= NULL
) {
2590 ret
= LTTCOMM_SESS_NOT_FOUND
;
2592 /* If no session name specified */
2593 ret
= LTTCOMM_SELECT_SESS
;
2597 /* Acquire lock for the session */
2598 session_lock(cmd_ctx
->session
);
2604 * Check domain type for specific "pre-action".
2606 switch (cmd_ctx
->lsm
->domain
.type
) {
2607 case LTTNG_DOMAIN_KERNEL
:
2608 /* Kernel tracer check */
2609 if (kernel_tracer_fd
== 0) {
2610 /* Basically, load kernel tracer modules */
2611 init_kernel_tracer();
2612 if (kernel_tracer_fd
== 0) {
2613 ret
= LTTCOMM_KERN_NA
;
2618 /* Need a session for kernel command */
2619 if (need_tracing_session
) {
2620 if (cmd_ctx
->session
->kernel_session
== NULL
) {
2621 ret
= create_kernel_session(cmd_ctx
->session
);
2623 ret
= LTTCOMM_KERN_SESS_FAIL
;
2628 /* Start the kernel consumer daemon */
2629 if (kconsumerd_pid
== 0 &&
2630 cmd_ctx
->lsm
->cmd_type
!= LTTNG_REGISTER_CONSUMER
) {
2631 ret
= start_kconsumerd();
2633 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
2639 case LTTNG_DOMAIN_UST_PID
:
2641 struct ltt_ust_session
*usess
;
2643 if (need_tracing_session
) {
2644 usess
= trace_ust_get_session_by_pid(
2645 &cmd_ctx
->session
->ust_session_list
,
2646 cmd_ctx
->lsm
->domain
.attr
.pid
);
2647 if (usess
== NULL
) {
2648 ret
= create_ust_session(cmd_ctx
->session
,
2649 &cmd_ctx
->lsm
->domain
);
2650 if (ret
!= LTTCOMM_OK
) {
2658 /* TODO Userspace tracer */
2662 /* Process by command type */
2663 switch (cmd_ctx
->lsm
->cmd_type
) {
2664 case LTTNG_ADD_CONTEXT
:
2666 ret
= cmd_add_context(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2667 cmd_ctx
->lsm
->u
.context
.channel_name
,
2668 cmd_ctx
->lsm
->u
.context
.event_name
,
2669 &cmd_ctx
->lsm
->u
.context
.ctx
);
2672 case LTTNG_DISABLE_CHANNEL
:
2674 ret
= cmd_disable_channel(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2675 cmd_ctx
->lsm
->u
.disable
.channel_name
);
2678 case LTTNG_DISABLE_EVENT
:
2680 ret
= cmd_disable_event(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2681 cmd_ctx
->lsm
->u
.disable
.channel_name
,
2682 cmd_ctx
->lsm
->u
.disable
.name
);
2686 case LTTNG_DISABLE_ALL_EVENT
:
2688 DBG("Disabling all kernel event");
2690 ret
= cmd_disable_event_all(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2691 cmd_ctx
->lsm
->u
.disable
.channel_name
);
2694 case LTTNG_ENABLE_CHANNEL
:
2696 ret
= cmd_enable_channel(cmd_ctx
->session
, &cmd_ctx
->lsm
->domain
,
2697 &cmd_ctx
->lsm
->u
.channel
.chan
);
2700 case LTTNG_ENABLE_EVENT
:
2702 ret
= cmd_enable_event(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2703 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2704 &cmd_ctx
->lsm
->u
.enable
.event
);
2707 case LTTNG_ENABLE_ALL_EVENT
:
2709 DBG("Enabling all kernel event");
2711 ret
= cmd_enable_event_all(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2712 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2713 cmd_ctx
->lsm
->u
.enable
.event
.type
);
2716 case LTTNG_LIST_TRACEPOINTS
:
2718 struct lttng_event
*events
;
2721 nb_events
= cmd_list_tracepoints(cmd_ctx
->lsm
->domain
.type
, &events
);
2722 if (nb_events
< 0) {
2728 * Setup lttng message with payload size set to the event list size in
2729 * bytes and then copy list into the llm payload.
2731 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_event
) * nb_events
);
2737 /* Copy event list into message payload */
2738 memcpy(cmd_ctx
->llm
->payload
, events
,
2739 sizeof(struct lttng_event
) * nb_events
);
2746 case LTTNG_START_TRACE
:
2748 ret
= cmd_start_trace(cmd_ctx
->session
);
2751 case LTTNG_STOP_TRACE
:
2753 ret
= cmd_stop_trace(cmd_ctx
->session
);
2756 case LTTNG_CREATE_SESSION
:
2758 tracepoint(create_session_start
);
2759 ret
= cmd_create_session(cmd_ctx
->lsm
->session
.name
,
2760 cmd_ctx
->lsm
->session
.path
);
2761 tracepoint(create_session_end
);
2764 case LTTNG_DESTROY_SESSION
:
2766 tracepoint(destroy_session_start
);
2767 ret
= cmd_destroy_session(cmd_ctx
->session
,
2768 cmd_ctx
->lsm
->session
.name
);
2769 tracepoint(destroy_session_end
);
2772 case LTTNG_LIST_DOMAINS
:
2775 struct lttng_domain
*domains
;
2777 nb_dom
= cmd_list_domains(cmd_ctx
->session
, &domains
);
2783 ret
= setup_lttng_msg(cmd_ctx
, nb_dom
* sizeof(struct lttng_domain
));
2788 /* Copy event list into message payload */
2789 memcpy(cmd_ctx
->llm
->payload
, domains
,
2790 nb_dom
* sizeof(struct lttng_domain
));
2797 case LTTNG_LIST_CHANNELS
:
2800 struct lttng_channel
*channels
;
2802 nb_chan
= cmd_list_channels(cmd_ctx
->session
, &channels
);
2808 ret
= setup_lttng_msg(cmd_ctx
, nb_chan
* sizeof(struct lttng_channel
));
2813 /* Copy event list into message payload */
2814 memcpy(cmd_ctx
->llm
->payload
, channels
,
2815 nb_chan
* sizeof(struct lttng_channel
));
2822 case LTTNG_LIST_EVENTS
:
2825 struct lttng_event
*events
= NULL
;
2827 nb_event
= cmd_list_events(cmd_ctx
->session
,
2828 cmd_ctx
->lsm
->u
.list
.channel_name
, &events
);
2834 ret
= setup_lttng_msg(cmd_ctx
, nb_event
* sizeof(struct lttng_event
));
2839 /* Copy event list into message payload */
2840 memcpy(cmd_ctx
->llm
->payload
, events
,
2841 nb_event
* sizeof(struct lttng_event
));
2848 case LTTNG_LIST_SESSIONS
:
2850 session_lock_list();
2852 if (session_list_ptr
->count
== 0) {
2853 ret
= LTTCOMM_NO_SESSION
;
2854 session_unlock_list();
2858 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_session
) *
2859 session_list_ptr
->count
);
2861 session_unlock_list();
2865 /* Filled the session array */
2866 list_lttng_sessions((struct lttng_session
*)(cmd_ctx
->llm
->payload
));
2868 session_unlock_list();
2873 case LTTNG_CALIBRATE
:
2875 ret
= cmd_calibrate(cmd_ctx
->lsm
->domain
.type
,
2876 &cmd_ctx
->lsm
->u
.calibrate
);
2879 case LTTNG_REGISTER_CONSUMER
:
2881 ret
= cmd_register_consumer(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2882 cmd_ctx
->lsm
->u
.reg
.path
);
2891 if (cmd_ctx
->llm
== NULL
) {
2892 DBG("Missing llm structure. Allocating one.");
2893 if (setup_lttng_msg(cmd_ctx
, 0) < 0) {
2897 /* Set return code */
2898 cmd_ctx
->llm
->ret_code
= ret
;
2900 if (cmd_ctx
->session
) {
2901 session_unlock(cmd_ctx
->session
);
2908 * This thread manage all clients request using the unix client socket for
2911 static void *thread_manage_clients(void *data
)
2913 int sock
= 0, ret
, i
, pollfd
;
2914 uint32_t revents
, nb_fd
;
2915 struct command_ctx
*cmd_ctx
= NULL
;
2916 struct lttng_poll_event events
;
2918 tracepoint(sessiond_th_cli_start
);
2920 DBG("[thread] Manage client started");
2922 ret
= lttcomm_listen_unix_sock(client_sock
);
2928 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2929 * more will be added to this poll set.
2931 ret
= create_thread_poll_set(&events
, 2);
2936 /* Add the application registration socket */
2937 ret
= lttng_poll_add(&events
, client_sock
, LPOLLIN
| LPOLLPRI
);
2943 * Notify parent pid that we are ready to accept command for client side.
2945 if (opt_sig_parent
) {
2946 kill(ppid
, SIGCHLD
);
2950 DBG("Accepting client command ...");
2952 tracepoint(sessiond_th_cli_poll
);
2954 nb_fd
= LTTNG_POLL_GETNB(&events
);
2956 /* Inifinite blocking call, waiting for transmission */
2957 ret
= lttng_poll_wait(&events
, -1);
2962 for (i
= 0; i
< nb_fd
; i
++) {
2963 /* Fetch once the poll data */
2964 revents
= LTTNG_POLL_GETEV(&events
, i
);
2965 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2967 /* Thread quit pipe has been closed. Killing thread. */
2968 ret
= check_thread_quit_pipe(pollfd
, revents
);
2973 /* Event on the registration socket */
2974 if (pollfd
== client_sock
) {
2975 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
2976 ERR("Client socket poll error");
2982 DBG("Wait for client response");
2984 sock
= lttcomm_accept_unix_sock(client_sock
);
2989 /* Allocate context command to process the client request */
2990 cmd_ctx
= malloc(sizeof(struct command_ctx
));
2991 if (cmd_ctx
== NULL
) {
2992 perror("malloc cmd_ctx");
2996 /* Allocate data buffer for reception */
2997 cmd_ctx
->lsm
= malloc(sizeof(struct lttcomm_session_msg
));
2998 if (cmd_ctx
->lsm
== NULL
) {
2999 perror("malloc cmd_ctx->lsm");
3003 cmd_ctx
->llm
= NULL
;
3004 cmd_ctx
->session
= NULL
;
3007 * Data is received from the lttng client. The struct
3008 * lttcomm_session_msg (lsm) contains the command and data request of
3011 DBG("Receiving data from client ...");
3012 ret
= lttcomm_recv_unix_sock(sock
, cmd_ctx
->lsm
,
3013 sizeof(struct lttcomm_session_msg
));
3015 DBG("Nothing recv() from client... continuing");
3021 // TODO: Validate cmd_ctx including sanity check for
3022 // security purpose.
3025 * This function dispatch the work to the kernel or userspace tracer
3026 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3027 * informations for the client. The command context struct contains
3028 * everything this function may needs.
3030 ret
= process_client_msg(cmd_ctx
);
3033 * TODO: Inform client somehow of the fatal error. At
3034 * this point, ret < 0 means that a malloc failed
3035 * (ENOMEM). Error detected but still accept command.
3037 clean_command_ctx(&cmd_ctx
);
3041 DBG("Sending response (size: %d, retcode: %s)",
3042 cmd_ctx
->lttng_msg_size
,
3043 lttng_get_readable_code(-cmd_ctx
->llm
->ret_code
));
3044 ret
= send_unix_sock(sock
, cmd_ctx
->llm
, cmd_ctx
->lttng_msg_size
);
3046 ERR("Failed to send data back to client");
3049 clean_command_ctx(&cmd_ctx
);
3051 /* End of transmission */
3056 DBG("Client thread dying");
3057 unlink(client_unix_sock_path
);
3061 lttng_poll_clean(&events
);
3062 clean_command_ctx(&cmd_ctx
);
3068 * usage function on stderr
3070 static void usage(void)
3072 fprintf(stderr
, "Usage: %s OPTIONS\n\nOptions:\n", progname
);
3073 fprintf(stderr
, " -h, --help Display this usage.\n");
3074 fprintf(stderr
, " -c, --client-sock PATH Specify path for the client unix socket\n");
3075 fprintf(stderr
, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3076 fprintf(stderr
, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3077 fprintf(stderr
, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3078 fprintf(stderr
, " -d, --daemonize Start as a daemon.\n");
3079 fprintf(stderr
, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3080 fprintf(stderr
, " -V, --version Show version number.\n");
3081 fprintf(stderr
, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3082 fprintf(stderr
, " -q, --quiet No output at all.\n");
3083 fprintf(stderr
, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3084 fprintf(stderr
, " --verbose-kconsumerd Verbose mode for kconsumerd. Activate DBG() macro.\n");
3088 * daemon argument parsing
3090 static int parse_args(int argc
, char **argv
)
3094 static struct option long_options
[] = {
3095 { "client-sock", 1, 0, 'c' },
3096 { "apps-sock", 1, 0, 'a' },
3097 { "kconsumerd-cmd-sock", 1, 0, 0 },
3098 { "kconsumerd-err-sock", 1, 0, 0 },
3099 { "daemonize", 0, 0, 'd' },
3100 { "sig-parent", 0, 0, 'S' },
3101 { "help", 0, 0, 'h' },
3102 { "group", 1, 0, 'g' },
3103 { "version", 0, 0, 'V' },
3104 { "quiet", 0, 0, 'q' },
3105 { "verbose", 0, 0, 'v' },
3106 { "verbose-kconsumerd", 0, 0, 'Z' },
3111 int option_index
= 0;
3112 c
= getopt_long(argc
, argv
, "dhqvVS" "a:c:g:s:E:C:Z",
3113 long_options
, &option_index
);
3120 fprintf(stderr
, "option %s", long_options
[option_index
].name
);
3122 fprintf(stderr
, " with arg %s\n", optarg
);
3126 snprintf(client_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3129 snprintf(apps_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3135 opt_tracing_group
= strdup(optarg
);
3141 fprintf(stdout
, "%s\n", VERSION
);
3147 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3150 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3156 /* Verbose level can increase using multiple -v */
3160 opt_verbose_kconsumerd
+= 1;
3163 /* Unknown option or other error.
3164 * Error is printed by getopt, just return */
3173 * Creates the two needed socket by the daemon.
3174 * apps_sock - The communication socket for all UST apps.
3175 * client_sock - The communication of the cli tool (lttng).
3177 static int init_daemon_socket(void)
3182 old_umask
= umask(0);
3184 /* Create client tool unix socket */
3185 client_sock
= lttcomm_create_unix_sock(client_unix_sock_path
);
3186 if (client_sock
< 0) {
3187 ERR("Create unix sock failed: %s", client_unix_sock_path
);
3192 /* File permission MUST be 660 */
3193 ret
= chmod(client_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3195 ERR("Set file permissions failed: %s", client_unix_sock_path
);
3200 /* Create the application unix socket */
3201 apps_sock
= lttcomm_create_unix_sock(apps_unix_sock_path
);
3202 if (apps_sock
< 0) {
3203 ERR("Create unix sock failed: %s", apps_unix_sock_path
);
3208 /* File permission MUST be 666 */
3209 ret
= chmod(apps_unix_sock_path
,
3210 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
| S_IROTH
| S_IWOTH
);
3212 ERR("Set file permissions failed: %s", apps_unix_sock_path
);
3223 * Check if the global socket is available, and if a daemon is answering at the
3224 * other side. If yes, error is returned.
3226 static int check_existing_daemon(void)
3228 if (access(client_unix_sock_path
, F_OK
) < 0 &&
3229 access(apps_unix_sock_path
, F_OK
) < 0) {
3233 /* Is there anybody out there ? */
3234 if (lttng_session_daemon_alive()) {
3242 * Set the tracing group gid onto the client socket.
3244 * Race window between mkdir and chown is OK because we are going from more
3245 * permissive (root.root) to les permissive (root.tracing).
3247 static int set_permissions(void)
3252 gid
= allowed_group();
3255 WARN("No tracing group detected");
3258 ERR("Missing tracing group. Aborting execution.");
3264 /* Set lttng run dir */
3265 ret
= chown(LTTNG_RUNDIR
, 0, gid
);
3267 ERR("Unable to set group on " LTTNG_RUNDIR
);
3271 /* lttng client socket path */
3272 ret
= chown(client_unix_sock_path
, 0, gid
);
3274 ERR("Unable to set group on %s", client_unix_sock_path
);
3278 /* kconsumerd error socket path */
3279 ret
= chown(kconsumerd_err_unix_sock_path
, 0, gid
);
3281 ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path
);
3285 DBG("All permissions are set");
3292 * Create the pipe used to wake up the kernel thread.
3294 static int create_kernel_poll_pipe(void)
3296 return pipe2(kernel_poll_pipe
, O_CLOEXEC
);
3300 * Create the application command pipe to wake thread_manage_apps.
3302 static int create_apps_cmd_pipe(void)
3304 return pipe2(apps_cmd_pipe
, O_CLOEXEC
);
3308 * Create the lttng run directory needed for all global sockets and pipe.
3310 static int create_lttng_rundir(void)
3314 ret
= mkdir(LTTNG_RUNDIR
, S_IRWXU
| S_IRWXG
);
3316 if (errno
!= EEXIST
) {
3317 ERR("Unable to create " LTTNG_RUNDIR
);
3329 * Setup sockets and directory needed by the kconsumerd communication with the
3332 static int set_kconsumerd_sockets(void)
3336 if (strlen(kconsumerd_err_unix_sock_path
) == 0) {
3337 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
,
3338 KCONSUMERD_ERR_SOCK_PATH
);
3341 if (strlen(kconsumerd_cmd_unix_sock_path
) == 0) {
3342 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
,
3343 KCONSUMERD_CMD_SOCK_PATH
);
3346 ret
= mkdir(KCONSUMERD_PATH
, S_IRWXU
| S_IRWXG
);
3348 if (errno
!= EEXIST
) {
3349 ERR("Failed to create " KCONSUMERD_PATH
);
3355 /* Create the kconsumerd error unix socket */
3356 kconsumerd_err_sock
=
3357 lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path
);
3358 if (kconsumerd_err_sock
< 0) {
3359 ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path
);
3364 /* File permission MUST be 660 */
3365 ret
= chmod(kconsumerd_err_unix_sock_path
,
3366 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3368 ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path
);
3378 * Signal handler for the daemon
3380 * Simply stop all worker threads, leaving main() return gracefully after
3381 * joining all threads and calling cleanup().
3383 static void sighandler(int sig
)
3387 DBG("SIGPIPE catched");
3390 DBG("SIGINT catched");
3394 DBG("SIGTERM catched");
3403 * Setup signal handler for :
3404 * SIGINT, SIGTERM, SIGPIPE
3406 static int set_signal_handler(void)
3409 struct sigaction sa
;
3412 if ((ret
= sigemptyset(&sigset
)) < 0) {
3413 perror("sigemptyset");
3417 sa
.sa_handler
= sighandler
;
3418 sa
.sa_mask
= sigset
;
3420 if ((ret
= sigaction(SIGTERM
, &sa
, NULL
)) < 0) {
3421 perror("sigaction");
3425 if ((ret
= sigaction(SIGINT
, &sa
, NULL
)) < 0) {
3426 perror("sigaction");
3430 if ((ret
= sigaction(SIGPIPE
, &sa
, NULL
)) < 0) {
3431 perror("sigaction");
3435 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3441 * Set open files limit to unlimited. This daemon can open a large number of
3442 * file descriptors in order to consumer multiple kernel traces.
3444 static void set_ulimit(void)
3449 /* The kernel does not allowed an infinite limit for open files */
3450 lim
.rlim_cur
= 65535;
3451 lim
.rlim_max
= 65535;
3453 ret
= setrlimit(RLIMIT_NOFILE
, &lim
);
3455 perror("failed to set open files limit");
3462 int main(int argc
, char **argv
)
3466 const char *home_path
;
3468 tracepoint(sessiond_boot_start
);
3470 /* Create thread quit pipe */
3471 if ((ret
= init_thread_quit_pipe()) < 0) {
3475 /* Parse arguments */
3477 if ((ret
= parse_args(argc
, argv
) < 0)) {
3490 /* Check if daemon is UID = 0 */
3491 is_root
= !getuid();
3494 ret
= create_lttng_rundir();
3499 if (strlen(apps_unix_sock_path
) == 0) {
3500 snprintf(apps_unix_sock_path
, PATH_MAX
,
3501 DEFAULT_GLOBAL_APPS_UNIX_SOCK
);
3504 if (strlen(client_unix_sock_path
) == 0) {
3505 snprintf(client_unix_sock_path
, PATH_MAX
,
3506 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
);
3509 /* Set global SHM for ust */
3510 if (strlen(wait_shm_path
) == 0) {
3511 snprintf(wait_shm_path
, PATH_MAX
,
3512 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH
);
3515 home_path
= get_home_dir();
3516 if (home_path
== NULL
) {
3517 /* TODO: Add --socket PATH option */
3518 ERR("Can't get HOME directory for sockets creation.");
3523 if (strlen(apps_unix_sock_path
) == 0) {
3524 snprintf(apps_unix_sock_path
, PATH_MAX
,
3525 DEFAULT_HOME_APPS_UNIX_SOCK
, home_path
);
3528 /* Set the cli tool unix socket path */
3529 if (strlen(client_unix_sock_path
) == 0) {
3530 snprintf(client_unix_sock_path
, PATH_MAX
,
3531 DEFAULT_HOME_CLIENT_UNIX_SOCK
, home_path
);
3534 /* Set global SHM for ust */
3535 if (strlen(wait_shm_path
) == 0) {
3536 snprintf(wait_shm_path
, PATH_MAX
,
3537 DEFAULT_HOME_APPS_WAIT_SHM_PATH
, geteuid());
3541 DBG("Client socket path %s", client_unix_sock_path
);
3542 DBG("Application socket path %s", apps_unix_sock_path
);
3545 * See if daemon already exist.
3547 if ((ret
= check_existing_daemon()) < 0) {
3548 ERR("Already running daemon.\n");
3550 * We do not goto exit because we must not cleanup()
3551 * because a daemon is already running.
3556 /* After this point, we can safely call cleanup() with "goto exit" */
3559 * These actions must be executed as root. We do that *after* setting up
3560 * the sockets path because we MUST make the check for another daemon using
3561 * those paths *before* trying to set the kernel consumer sockets and init
3565 ret
= set_kconsumerd_sockets();
3570 /* Setup kernel tracer */
3571 init_kernel_tracer();
3573 /* Set ulimit for open files */
3577 if ((ret
= set_signal_handler()) < 0) {
3581 /* Setup the needed unix socket */
3582 if ((ret
= init_daemon_socket()) < 0) {
3586 /* Set credentials to socket */
3587 if (is_root
&& ((ret
= set_permissions()) < 0)) {
3591 /* Get parent pid if -S, --sig-parent is specified. */
3592 if (opt_sig_parent
) {
3596 /* Setup the kernel pipe for waking up the kernel thread */
3597 if ((ret
= create_kernel_poll_pipe()) < 0) {
3601 /* Setup the thread apps communication pipe. */
3602 if ((ret
= create_apps_cmd_pipe()) < 0) {
3606 /* Init UST command queue. */
3607 cds_wfq_init(&ust_cmd_queue
.queue
);
3610 * Get session list pointer. This pointer MUST NOT be free(). This list is
3611 * statically declared in session.c
3613 session_list_ptr
= session_get_list();
3615 /* Set up max poll set size */
3616 lttng_poll_set_max_size();
3618 /* Create thread to manage the client socket */
3619 ret
= pthread_create(&client_thread
, NULL
,
3620 thread_manage_clients
, (void *) NULL
);
3622 perror("pthread_create clients");
3626 /* Create thread to dispatch registration */
3627 ret
= pthread_create(&dispatch_thread
, NULL
,
3628 thread_dispatch_ust_registration
, (void *) NULL
);
3630 perror("pthread_create dispatch");
3634 /* Create thread to manage application registration. */
3635 ret
= pthread_create(®_apps_thread
, NULL
,
3636 thread_registration_apps
, (void *) NULL
);
3638 perror("pthread_create registration");
3642 /* Create thread to manage application socket */
3643 ret
= pthread_create(&apps_thread
, NULL
,
3644 thread_manage_apps
, (void *) NULL
);
3646 perror("pthread_create apps");
3650 /* Create kernel thread to manage kernel event */
3651 ret
= pthread_create(&kernel_thread
, NULL
,
3652 thread_manage_kernel
, (void *) NULL
);
3654 perror("pthread_create kernel");
3658 tracepoint(sessiond_boot_end
);
3660 ret
= pthread_join(kernel_thread
, &status
);
3662 perror("pthread_join");
3663 goto error
; /* join error, exit without cleanup */
3667 ret
= pthread_join(apps_thread
, &status
);
3669 perror("pthread_join");
3670 goto error
; /* join error, exit without cleanup */
3674 ret
= pthread_join(reg_apps_thread
, &status
);
3676 perror("pthread_join");
3677 goto error
; /* join error, exit without cleanup */
3681 ret
= pthread_join(dispatch_thread
, &status
);
3683 perror("pthread_join");
3684 goto error
; /* join error, exit without cleanup */
3688 ret
= pthread_join(client_thread
, &status
);
3690 perror("pthread_join");
3691 goto error
; /* join error, exit without cleanup */
3694 ret
= join_kconsumerd_thread();
3696 perror("join_kconsumerd");
3697 goto error
; /* join error, exit without cleanup */
3703 * cleanup() is called when no other thread is running.