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();
373 bench_print_ust_unregister();
376 if (getenv("BENCH_BOOT_PROCESS")) {
377 bench_print_boot_process();
385 * Send data on a unix socket using the liblttsessiondcomm API.
387 * Return lttcomm error code.
389 static int send_unix_sock(int sock
, void *buf
, size_t len
)
391 /* Check valid length */
396 return lttcomm_send_unix_sock(sock
, buf
, len
);
400 * Free memory of a command context structure.
402 static void clean_command_ctx(struct command_ctx
**cmd_ctx
)
404 DBG("Clean command context structure");
406 if ((*cmd_ctx
)->llm
) {
407 free((*cmd_ctx
)->llm
);
409 if ((*cmd_ctx
)->lsm
) {
410 free((*cmd_ctx
)->lsm
);
418 * Send all stream fds of kernel channel to the consumer.
420 static int send_kconsumerd_channel_fds(int sock
,
421 struct ltt_kernel_channel
*channel
)
425 struct ltt_kernel_stream
*stream
;
426 struct lttcomm_kconsumerd_header lkh
;
427 struct lttcomm_kconsumerd_msg lkm
;
429 DBG("Sending fds of channel %s to kernel consumer",
430 channel
->channel
->name
);
432 nb_fd
= channel
->stream_count
;
435 lkh
.payload_size
= nb_fd
* sizeof(struct lttcomm_kconsumerd_msg
);
436 lkh
.cmd_type
= ADD_STREAM
;
438 DBG("Sending kconsumerd header");
440 ret
= lttcomm_send_unix_sock(sock
, &lkh
,
441 sizeof(struct lttcomm_kconsumerd_header
));
443 perror("send kconsumerd header");
447 cds_list_for_each_entry(stream
, &channel
->stream_list
.head
, list
) {
448 if (stream
->fd
!= 0) {
450 lkm
.state
= stream
->state
;
451 lkm
.max_sb_size
= channel
->channel
->attr
.subbuf_size
;
452 lkm
.output
= channel
->channel
->attr
.output
;
453 strncpy(lkm
.path_name
, stream
->pathname
, PATH_MAX
);
454 lkm
.path_name
[PATH_MAX
- 1] = '\0';
456 DBG("Sending fd %d to kconsumerd", lkm
.fd
);
458 ret
= lttcomm_send_fds_unix_sock(sock
, &lkm
,
459 &lkm
.fd
, 1, sizeof(lkm
));
461 perror("send kconsumerd fd");
467 DBG("Kconsumerd channel fds sent");
476 * Send all stream fds of the kernel session to the consumer.
478 static int send_kconsumerd_fds(struct ltt_kernel_session
*session
)
481 struct ltt_kernel_channel
*chan
;
482 struct lttcomm_kconsumerd_header lkh
;
483 struct lttcomm_kconsumerd_msg lkm
;
486 lkh
.payload_size
= sizeof(struct lttcomm_kconsumerd_msg
);
487 lkh
.cmd_type
= ADD_STREAM
;
489 DBG("Sending kconsumerd header for metadata");
491 ret
= lttcomm_send_unix_sock(session
->consumer_fd
, &lkh
,
492 sizeof(struct lttcomm_kconsumerd_header
));
494 perror("send kconsumerd header");
498 DBG("Sending metadata stream fd");
500 /* Extra protection. It's NOT suppose to be set to 0 at this point */
501 if (session
->consumer_fd
== 0) {
502 session
->consumer_fd
= kconsumerd_cmd_sock
;
505 if (session
->metadata_stream_fd
!= 0) {
506 /* Send metadata stream fd first */
507 lkm
.fd
= session
->metadata_stream_fd
;
508 lkm
.state
= ACTIVE_FD
;
509 lkm
.max_sb_size
= session
->metadata
->conf
->attr
.subbuf_size
;
510 lkm
.output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
511 strncpy(lkm
.path_name
, session
->metadata
->pathname
, PATH_MAX
);
512 lkm
.path_name
[PATH_MAX
- 1] = '\0';
514 ret
= lttcomm_send_fds_unix_sock(session
->consumer_fd
, &lkm
,
515 &lkm
.fd
, 1, sizeof(lkm
));
517 perror("send kconsumerd fd");
522 cds_list_for_each_entry(chan
, &session
->channel_list
.head
, list
) {
523 ret
= send_kconsumerd_channel_fds(session
->consumer_fd
, chan
);
529 DBG("Kconsumerd fds (metadata and channel streams) sent");
538 * Notify UST applications using the shm mmap futex.
540 static int notify_ust_apps(int active
)
544 DBG("Notifying applications of session daemon state: %d", active
);
546 tracepoint(ust_notify_apps_start
);
548 /* See shm.c for this call implying mmap, shm and futex calls */
549 wait_shm_mmap
= shm_ust_get_mmap(wait_shm_path
, is_root
);
550 if (wait_shm_mmap
== NULL
) {
554 /* Wake waiting process */
555 futex_wait_update((int32_t *) wait_shm_mmap
, active
);
557 tracepoint(ust_notify_apps_stop
);
559 /* Apps notified successfully */
567 * Setup the outgoing data buffer for the response (llm) by allocating the
568 * right amount of memory and copying the original information from the lsm
571 * Return total size of the buffer pointed by buf.
573 static int setup_lttng_msg(struct command_ctx
*cmd_ctx
, size_t size
)
579 cmd_ctx
->llm
= malloc(sizeof(struct lttcomm_lttng_msg
) + buf_size
);
580 if (cmd_ctx
->llm
== NULL
) {
586 /* Copy common data */
587 cmd_ctx
->llm
->cmd_type
= cmd_ctx
->lsm
->cmd_type
;
588 cmd_ctx
->llm
->pid
= cmd_ctx
->lsm
->domain
.attr
.pid
;
590 cmd_ctx
->llm
->data_size
= size
;
591 cmd_ctx
->lttng_msg_size
= sizeof(struct lttcomm_lttng_msg
) + buf_size
;
600 * Update the kernel poll set of all channel fd available over all tracing
601 * session. Add the wakeup pipe at the end of the set.
603 static int update_kernel_poll(struct lttng_poll_event
*events
)
606 struct ltt_session
*session
;
607 struct ltt_kernel_channel
*channel
;
609 DBG("Updating kernel poll set");
612 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
613 session_lock(session
);
614 if (session
->kernel_session
== NULL
) {
615 session_unlock(session
);
619 cds_list_for_each_entry(channel
,
620 &session
->kernel_session
->channel_list
.head
, list
) {
621 /* Add channel fd to the kernel poll set */
622 ret
= lttng_poll_add(events
, channel
->fd
, LPOLLIN
| LPOLLRDNORM
);
624 session_unlock(session
);
627 DBG("Channel fd %d added to kernel set", channel
->fd
);
629 session_unlock(session
);
631 session_unlock_list();
636 session_unlock_list();
641 * Find the channel fd from 'fd' over all tracing session. When found, check
642 * for new channel stream and send those stream fds to the kernel consumer.
644 * Useful for CPU hotplug feature.
646 static int update_kernel_stream(int fd
)
649 struct ltt_session
*session
;
650 struct ltt_kernel_channel
*channel
;
652 DBG("Updating kernel streams for channel fd %d", fd
);
655 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
656 session_lock(session
);
657 if (session
->kernel_session
== NULL
) {
658 session_unlock(session
);
662 /* This is not suppose to be 0 but this is an extra security check */
663 if (session
->kernel_session
->consumer_fd
== 0) {
664 session
->kernel_session
->consumer_fd
= kconsumerd_cmd_sock
;
667 cds_list_for_each_entry(channel
,
668 &session
->kernel_session
->channel_list
.head
, list
) {
669 if (channel
->fd
== fd
) {
670 DBG("Channel found, updating kernel streams");
671 ret
= kernel_open_channel_stream(channel
);
677 * Have we already sent fds to the consumer? If yes, it means
678 * that tracing is started so it is safe to send our updated
681 if (session
->kernel_session
->kconsumer_fds_sent
== 1) {
682 ret
= send_kconsumerd_channel_fds(
683 session
->kernel_session
->consumer_fd
, channel
);
691 session_unlock(session
);
693 session_unlock_list();
697 session_unlock(session
);
698 session_unlock_list();
703 * This thread manage event coming from the kernel.
705 * Features supported in this thread:
708 static void *thread_manage_kernel(void *data
)
710 int ret
, i
, pollfd
, update_poll_flag
= 1;
711 uint32_t revents
, nb_fd
;
713 struct lttng_poll_event events
;
715 tracepoint(sessiond_th_kern_start
);
717 DBG("Thread manage kernel started");
719 ret
= create_thread_poll_set(&events
, 2);
724 ret
= lttng_poll_add(&events
, kernel_poll_pipe
[0], LPOLLIN
);
730 if (update_poll_flag
== 1) {
732 * Reset number of fd in the poll set. Always 2 since there is the thread
733 * quit pipe and the kernel pipe.
737 ret
= update_kernel_poll(&events
);
741 update_poll_flag
= 0;
744 nb_fd
= LTTNG_POLL_GETNB(&events
);
746 DBG("Thread kernel polling on %d fds", nb_fd
);
748 /* Zeroed the poll events */
749 lttng_poll_reset(&events
);
751 tracepoint(sessiond_th_kern_poll
);
753 /* Poll infinite value of time */
754 ret
= lttng_poll_wait(&events
, -1);
757 } else if (ret
== 0) {
758 /* Should not happen since timeout is infinite */
759 ERR("Return value of poll is 0 with an infinite timeout.\n"
760 "This should not have happened! Continuing...");
764 for (i
= 0; i
< nb_fd
; i
++) {
765 /* Fetch once the poll data */
766 revents
= LTTNG_POLL_GETEV(&events
, i
);
767 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
769 /* Thread quit pipe has been closed. Killing thread. */
770 ret
= check_thread_quit_pipe(pollfd
, revents
);
775 /* Check for data on kernel pipe */
776 if (pollfd
== kernel_poll_pipe
[0] && (revents
& LPOLLIN
)) {
777 ret
= read(kernel_poll_pipe
[0], &tmp
, 1);
778 update_poll_flag
= 1;
782 * New CPU detected by the kernel. Adding kernel stream to
783 * kernel session and updating the kernel consumer
785 if (revents
& LPOLLIN
) {
786 ret
= update_kernel_stream(pollfd
);
792 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
793 * and unregister kernel stream at this point.
801 DBG("Kernel thread dying");
802 close(kernel_poll_pipe
[0]);
803 close(kernel_poll_pipe
[1]);
805 lttng_poll_clean(&events
);
811 * This thread manage the kconsumerd error sent back to the session daemon.
813 static void *thread_manage_kconsumerd(void *data
)
815 int sock
= 0, i
, ret
, pollfd
;
816 uint32_t revents
, nb_fd
;
817 enum lttcomm_return_code code
;
818 struct lttng_poll_event events
;
820 tracepoint(sessiond_th_kcon_start
);
822 DBG("[thread] Manage kconsumerd started");
824 ret
= lttcomm_listen_unix_sock(kconsumerd_err_sock
);
830 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
831 * Nothing more will be added to this poll set.
833 ret
= create_thread_poll_set(&events
, 2);
838 ret
= lttng_poll_add(&events
, kconsumerd_err_sock
, LPOLLIN
| LPOLLRDHUP
);
843 nb_fd
= LTTNG_POLL_GETNB(&events
);
845 tracepoint(sessiond_th_kcon_poll
);
847 /* Inifinite blocking call, waiting for transmission */
848 ret
= lttng_poll_wait(&events
, -1);
853 for (i
= 0; i
< nb_fd
; i
++) {
854 /* Fetch once the poll data */
855 revents
= LTTNG_POLL_GETEV(&events
, i
);
856 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
858 /* Thread quit pipe has been closed. Killing thread. */
859 ret
= check_thread_quit_pipe(pollfd
, revents
);
864 /* Event on the registration socket */
865 if (pollfd
== kconsumerd_err_sock
) {
866 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
867 ERR("Kconsumerd err socket poll error");
873 sock
= lttcomm_accept_unix_sock(kconsumerd_err_sock
);
878 /* Getting status code from kconsumerd */
879 ret
= lttcomm_recv_unix_sock(sock
, &code
,
880 sizeof(enum lttcomm_return_code
));
885 if (code
== KCONSUMERD_COMMAND_SOCK_READY
) {
886 kconsumerd_cmd_sock
=
887 lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path
);
888 if (kconsumerd_cmd_sock
< 0) {
889 sem_post(&kconsumerd_sem
);
890 perror("kconsumerd connect");
893 /* Signal condition to tell that the kconsumerd is ready */
894 sem_post(&kconsumerd_sem
);
895 DBG("Kconsumerd command socket ready");
897 DBG("Kconsumerd error when waiting for SOCK_READY : %s",
898 lttcomm_get_readable_code(-code
));
902 /* Remove the kconsumerd error sock since we've established a connexion */
903 ret
= lttng_poll_del(&events
, kconsumerd_err_sock
);
908 ret
= lttng_poll_add(&events
, sock
, LPOLLIN
| LPOLLRDHUP
);
913 /* Update number of fd */
914 nb_fd
= LTTNG_POLL_GETNB(&events
);
916 /* Inifinite blocking call, waiting for transmission */
917 ret
= lttng_poll_wait(&events
, -1);
922 for (i
= 0; i
< nb_fd
; i
++) {
923 /* Fetch once the poll data */
924 revents
= LTTNG_POLL_GETEV(&events
, i
);
925 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
927 /* Thread quit pipe has been closed. Killing thread. */
928 ret
= check_thread_quit_pipe(pollfd
, revents
);
933 /* Event on the kconsumerd socket */
934 if (pollfd
== sock
) {
935 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
936 ERR("Kconsumerd err socket second poll error");
942 /* Wait for any kconsumerd error */
943 ret
= lttcomm_recv_unix_sock(sock
, &code
,
944 sizeof(enum lttcomm_return_code
));
946 ERR("Kconsumerd closed the command socket");
950 ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code
));
953 DBG("Kconsumerd thread dying");
954 close(kconsumerd_err_sock
);
955 close(kconsumerd_cmd_sock
);
958 unlink(kconsumerd_err_unix_sock_path
);
959 unlink(kconsumerd_cmd_unix_sock_path
);
962 lttng_poll_clean(&events
);
968 * This thread manage application communication.
970 static void *thread_manage_apps(void *data
)
973 uint32_t revents
, nb_fd
;
974 struct ust_command ust_cmd
;
975 struct lttng_poll_event events
;
977 tracepoint(sessiond_th_apps_start
);
979 DBG("[thread] Manage application started");
981 ret
= create_thread_poll_set(&events
, 2);
986 ret
= lttng_poll_add(&events
, apps_cmd_pipe
[0], LPOLLIN
| LPOLLRDHUP
);
992 /* Zeroed the events structure */
993 lttng_poll_reset(&events
);
995 nb_fd
= LTTNG_POLL_GETNB(&events
);
997 DBG("Apps thread polling on %d fds", nb_fd
);
999 tracepoint(sessiond_th_apps_poll
);
1001 /* Inifinite blocking call, waiting for transmission */
1002 ret
= lttng_poll_wait(&events
, -1);
1007 for (i
= 0; i
< nb_fd
; i
++) {
1008 /* Fetch once the poll data */
1009 revents
= LTTNG_POLL_GETEV(&events
, i
);
1010 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
1012 /* Thread quit pipe has been closed. Killing thread. */
1013 ret
= check_thread_quit_pipe(pollfd
, revents
);
1018 /* Inspect the apps cmd pipe */
1019 if (pollfd
== apps_cmd_pipe
[0]) {
1020 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1021 ERR("Apps command pipe error");
1023 } else if (revents
& LPOLLIN
) {
1024 tracepoint(ust_register_read_start
);
1026 ret
= read(apps_cmd_pipe
[0], &ust_cmd
, sizeof(ust_cmd
));
1027 if (ret
< 0 || ret
< sizeof(ust_cmd
)) {
1028 perror("read apps cmd pipe");
1031 tracepoint(ust_register_read_stop
);
1033 tracepoint(ust_register_add_start
);
1034 /* Register applicaton to the session daemon */
1035 ret
= ust_app_register(&ust_cmd
.reg_msg
,
1038 /* Only critical ENOMEM error can be returned here */
1041 tracepoint(ust_register_add_stop
);
1043 tracepoint(ust_register_done_start
);
1044 ret
= ustctl_register_done(ust_cmd
.sock
);
1047 * If the registration is not possible, we simply
1048 * unregister the apps and continue
1050 ust_app_unregister(ust_cmd
.sock
);
1053 * We just need here to monitor the close of the UST
1054 * socket and poll set monitor those by default.
1056 ret
= lttng_poll_add(&events
, ust_cmd
.sock
, 0);
1061 DBG("Apps with sock %d added to poll set",
1064 tracepoint(ust_register_done_stop
);
1069 * At this point, we know that a registered application made
1070 * the event at poll_wait.
1072 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1073 /* Removing from the poll set */
1074 ret
= lttng_poll_del(&events
, pollfd
);
1080 ust_app_unregister(pollfd
);
1088 DBG("Application communication apps dying");
1089 close(apps_cmd_pipe
[0]);
1090 close(apps_cmd_pipe
[1]);
1092 lttng_poll_clean(&events
);
1098 * Dispatch request from the registration threads to the application
1099 * communication thread.
1101 static void *thread_dispatch_ust_registration(void *data
)
1104 struct cds_wfq_node
*node
;
1105 struct ust_command
*ust_cmd
= NULL
;
1107 tracepoint(sessiond_th_dispatch_start
);
1109 DBG("[thread] Dispatch UST command started");
1111 while (!dispatch_thread_exit
) {
1112 /* Atomically prepare the queue futex */
1113 futex_nto1_prepare(&ust_cmd_queue
.futex
);
1116 tracepoint(sessiond_th_dispatch_block
);
1118 /* Dequeue command for registration */
1119 node
= cds_wfq_dequeue_blocking(&ust_cmd_queue
.queue
);
1121 DBG("Waked up but nothing in the UST command queue");
1122 /* Continue thread execution */
1126 tracepoint(ust_dispatch_register_start
);
1128 ust_cmd
= caa_container_of(node
, struct ust_command
, node
);
1130 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1131 " gid:%d sock:%d name:%s (version %d.%d)",
1132 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1133 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1134 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1135 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1137 * Inform apps thread of the new application registration. This
1138 * call is blocking so we can be assured that the data will be read
1139 * at some point in time or wait to the end of the world :)
1141 ret
= write(apps_cmd_pipe
[1], ust_cmd
,
1142 sizeof(struct ust_command
));
1144 perror("write apps cmd pipe");
1145 if (errno
== EBADF
) {
1147 * We can't inform the application thread to process
1148 * registration. We will exit or else application
1149 * registration will not occur and tracing will never
1156 } while (node
!= NULL
);
1158 tracepoint(ust_dispatch_register_stop
);
1160 /* Futex wait on queue. Blocking call on futex() */
1161 futex_nto1_wait(&ust_cmd_queue
.futex
);
1165 DBG("Dispatch thread dying");
1170 * This thread manage application registration.
1172 static void *thread_registration_apps(void *data
)
1174 int sock
= 0, i
, ret
, pollfd
;
1175 uint32_t revents
, nb_fd
;
1176 struct lttng_poll_event events
;
1178 * Get allocated in this thread, enqueued to a global queue, dequeued and
1179 * freed in the manage apps thread.
1181 struct ust_command
*ust_cmd
= NULL
;
1183 tracepoint(sessiond_th_reg_start
);
1185 DBG("[thread] Manage application registration started");
1187 ret
= lttcomm_listen_unix_sock(apps_sock
);
1193 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1194 * more will be added to this poll set.
1196 ret
= create_thread_poll_set(&events
, 2);
1201 /* Add the application registration socket */
1202 ret
= lttng_poll_add(&events
, apps_sock
, LPOLLIN
| LPOLLRDHUP
);
1207 /* Notify all applications to register */
1208 ret
= notify_ust_apps(1);
1210 ERR("Failed to notify applications or create the wait shared memory.\n"
1211 "Execution continues but there might be problem for already\n"
1212 "running applications that wishes to register.");
1216 DBG("Accepting application registration");
1218 tracepoint(sessiond_th_reg_poll
);
1220 nb_fd
= LTTNG_POLL_GETNB(&events
);
1222 /* Inifinite blocking call, waiting for transmission */
1223 ret
= lttng_poll_wait(&events
, -1);
1228 for (i
= 0; i
< nb_fd
; i
++) {
1229 /* Fetch once the poll data */
1230 revents
= LTTNG_POLL_GETEV(&events
, i
);
1231 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
1233 /* Thread quit pipe has been closed. Killing thread. */
1234 ret
= check_thread_quit_pipe(pollfd
, revents
);
1239 /* Event on the registration socket */
1240 if (pollfd
== apps_sock
) {
1241 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1242 ERR("Register apps socket poll error");
1244 } else if (revents
& LPOLLIN
) {
1245 /* Registration starts here. Recording cycles */
1246 tracepoint(ust_register_start
);
1248 sock
= lttcomm_accept_unix_sock(apps_sock
);
1253 /* Create UST registration command for enqueuing */
1254 ust_cmd
= malloc(sizeof(struct ust_command
));
1255 if (ust_cmd
== NULL
) {
1256 perror("ust command malloc");
1261 * Using message-based transmissions to ensure we don't
1262 * have to deal with partially received messages.
1264 ret
= lttcomm_recv_unix_sock(sock
, &ust_cmd
->reg_msg
,
1265 sizeof(struct ust_register_msg
));
1266 if (ret
< 0 || ret
< sizeof(struct ust_register_msg
)) {
1268 perror("lttcomm_recv_unix_sock register apps");
1270 ERR("Wrong size received on apps register");
1277 ust_cmd
->sock
= sock
;
1279 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1280 " gid:%d sock:%d name:%s (version %d.%d)",
1281 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1282 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1283 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1284 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1287 * Lock free enqueue the registration request. The red pill
1288 * has been taken! This apps will be part of the *system*.
1290 cds_wfq_enqueue(&ust_cmd_queue
.queue
, &ust_cmd
->node
);
1293 * Wake the registration queue futex. Implicit memory
1294 * barrier with the exchange in cds_wfq_enqueue.
1296 futex_nto1_wake(&ust_cmd_queue
.futex
);
1298 tracepoint(ust_register_stop
);
1305 DBG("UST Registration thread dying");
1307 /* Notify that the registration thread is gone */
1312 unlink(apps_unix_sock_path
);
1314 lttng_poll_clean(&events
);
1320 * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
1321 * exec or it will fails.
1323 static int spawn_kconsumerd_thread(void)
1327 /* Setup semaphore */
1328 sem_init(&kconsumerd_sem
, 0, 0);
1330 ret
= pthread_create(&kconsumerd_thread
, NULL
,
1331 thread_manage_kconsumerd
, (void *) NULL
);
1333 perror("pthread_create kconsumerd");
1337 /* Wait for the kconsumerd thread to be ready */
1338 sem_wait(&kconsumerd_sem
);
1340 if (kconsumerd_pid
== 0) {
1341 ERR("Kconsumerd did not start");
1348 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1353 * Join kernel consumer thread
1355 static int join_kconsumerd_thread(void)
1360 if (kconsumerd_pid
!= 0) {
1361 ret
= kill(kconsumerd_pid
, SIGTERM
);
1363 ERR("Error killing kconsumerd");
1366 return pthread_join(kconsumerd_thread
, &status
);
1373 * Fork and exec a kernel consumer daemon (kconsumerd).
1375 * Return pid if successful else -1.
1377 static pid_t
spawn_kconsumerd(void)
1381 const char *verbosity
;
1383 DBG("Spawning kconsumerd");
1390 if (opt_verbose
> 1 || opt_verbose_kconsumerd
) {
1391 verbosity
= "--verbose";
1393 verbosity
= "--quiet";
1395 execl(INSTALL_BIN_PATH
"/ltt-kconsumerd",
1396 "ltt-kconsumerd", verbosity
, NULL
);
1398 perror("kernel start consumer exec");
1401 } else if (pid
> 0) {
1405 perror("kernel start consumer fork");
1415 * Spawn the kconsumerd daemon and session daemon thread.
1417 static int start_kconsumerd(void)
1421 pthread_mutex_lock(&kconsumerd_pid_mutex
);
1422 if (kconsumerd_pid
!= 0) {
1423 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1427 ret
= spawn_kconsumerd();
1429 ERR("Spawning kconsumerd failed");
1430 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1431 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1435 /* Setting up the global kconsumerd_pid */
1436 kconsumerd_pid
= ret
;
1437 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1439 DBG("Kconsumerd pid %d", ret
);
1441 DBG("Spawning kconsumerd thread");
1442 ret
= spawn_kconsumerd_thread();
1444 ERR("Fatal error spawning kconsumerd thread");
1456 * modprobe_kernel_modules
1458 static int modprobe_kernel_modules(void)
1463 for (i
= 0; i
< ARRAY_SIZE(kernel_modules_list
); i
++) {
1464 ret
= snprintf(modprobe
, sizeof(modprobe
),
1465 "/sbin/modprobe %s%s",
1466 kernel_modules_list
[i
].required
? "" : "--quiet ",
1467 kernel_modules_list
[i
].name
);
1469 perror("snprintf modprobe");
1472 modprobe
[sizeof(modprobe
) - 1] = '\0';
1473 ret
= system(modprobe
);
1475 ERR("Unable to launch modprobe for module %s",
1476 kernel_modules_list
[i
].name
);
1477 } else if (kernel_modules_list
[i
].required
1478 && WEXITSTATUS(ret
) != 0) {
1479 ERR("Unable to load module %s",
1480 kernel_modules_list
[i
].name
);
1482 DBG("Modprobe successfully %s",
1483 kernel_modules_list
[i
].name
);
1494 static int mount_debugfs(char *path
)
1497 char *type
= "debugfs";
1499 ret
= mkdir_recursive(path
, S_IRWXU
| S_IRWXG
, geteuid(), getegid());
1501 PERROR("Cannot create debugfs path");
1505 ret
= mount(type
, path
, type
, 0, NULL
);
1507 PERROR("Cannot mount debugfs");
1511 DBG("Mounted debugfs successfully at %s", path
);
1518 * Setup necessary data for kernel tracer action.
1520 static void init_kernel_tracer(void)
1523 char *proc_mounts
= "/proc/mounts";
1525 char *debugfs_path
= NULL
, *lttng_path
= NULL
;
1528 /* Detect debugfs */
1529 fp
= fopen(proc_mounts
, "r");
1531 ERR("Unable to probe %s", proc_mounts
);
1535 while (fgets(line
, sizeof(line
), fp
) != NULL
) {
1536 if (strstr(line
, "debugfs") != NULL
) {
1537 /* Remove first string */
1539 /* Dup string here so we can reuse line later on */
1540 debugfs_path
= strdup(strtok(NULL
, " "));
1541 DBG("Got debugfs path : %s", debugfs_path
);
1548 /* Mount debugfs if needded */
1549 if (debugfs_path
== NULL
) {
1550 ret
= asprintf(&debugfs_path
, "/mnt/debugfs");
1552 perror("asprintf debugfs path");
1555 ret
= mount_debugfs(debugfs_path
);
1557 perror("Cannot mount debugfs");
1562 /* Modprobe lttng kernel modules */
1563 ret
= modprobe_kernel_modules();
1568 /* Setup lttng kernel path */
1569 ret
= asprintf(<tng_path
, "%s/lttng", debugfs_path
);
1571 perror("asprintf lttng path");
1575 /* Open debugfs lttng */
1576 kernel_tracer_fd
= open(lttng_path
, O_RDWR
);
1577 if (kernel_tracer_fd
< 0) {
1578 DBG("Failed to open %s", lttng_path
);
1584 DBG("Kernel tracer fd %d", kernel_tracer_fd
);
1594 WARN("No kernel tracer available");
1595 kernel_tracer_fd
= 0;
1600 * Init tracing by creating trace directory and sending fds kernel consumer.
1602 static int init_kernel_tracing(struct ltt_kernel_session
*session
)
1606 if (session
->kconsumer_fds_sent
== 0) {
1608 * Assign default kernel consumer socket if no consumer assigned to the
1609 * kernel session. At this point, it's NOT suppose to be 0 but this is
1610 * an extra security check.
1612 if (session
->consumer_fd
== 0) {
1613 session
->consumer_fd
= kconsumerd_cmd_sock
;
1616 ret
= send_kconsumerd_fds(session
);
1618 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1622 session
->kconsumer_fds_sent
= 1;
1630 * Create an UST session and add it to the session ust list.
1632 static int create_ust_session(struct ltt_session
*session
,
1633 struct lttng_domain
*domain
)
1636 struct ltt_ust_session
*lus
= NULL
;
1637 struct ust_app
*app
;
1639 switch (domain
->type
) {
1640 case LTTNG_DOMAIN_UST_PID
:
1641 app
= ust_app_get_by_pid(domain
->attr
.pid
);
1643 ret
= LTTCOMM_APP_NOT_FOUND
;
1648 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
1652 DBG("Creating UST session");
1654 lus
= trace_ust_create_session(session
->path
, domain
->attr
.pid
, domain
);
1656 ret
= LTTCOMM_UST_SESS_FAIL
;
1660 ret
= mkdir_recursive(lus
->path
, S_IRWXU
| S_IRWXG
,
1661 geteuid(), allowed_group());
1663 if (ret
!= -EEXIST
) {
1664 ERR("Trace directory creation error");
1665 ret
= LTTCOMM_UST_SESS_FAIL
;
1670 /* Create session on the UST tracer */
1671 ret
= ustctl_create_session(app
->sock
, lus
);
1673 ret
= LTTCOMM_UST_SESS_FAIL
;
1677 cds_list_add(&lus
->list
, &session
->ust_session_list
.head
);
1678 session
->ust_session_list
.count
++;
1688 * Create a kernel tracer session then create the default channel.
1690 static int create_kernel_session(struct ltt_session
*session
)
1694 DBG("Creating kernel session");
1696 ret
= kernel_create_session(session
, kernel_tracer_fd
);
1698 ret
= LTTCOMM_KERN_SESS_FAIL
;
1702 /* Set kernel consumer socket fd */
1703 if (kconsumerd_cmd_sock
) {
1704 session
->kernel_session
->consumer_fd
= kconsumerd_cmd_sock
;
1707 ret
= mkdir_recursive(session
->kernel_session
->trace_path
,
1708 S_IRWXU
| S_IRWXG
, geteuid(), allowed_group());
1710 if (ret
!= -EEXIST
) {
1711 ERR("Trace directory creation error");
1721 * Using the session list, filled a lttng_session array to send back to the
1722 * client for session listing.
1724 * The session list lock MUST be acquired before calling this function. Use
1725 * session_lock_list() and session_unlock_list().
1727 static void list_lttng_sessions(struct lttng_session
*sessions
)
1730 struct ltt_session
*session
;
1732 DBG("Getting all available session");
1734 * Iterate over session list and append data after the control struct in
1737 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
1738 strncpy(sessions
[i
].path
, session
->path
, PATH_MAX
);
1739 sessions
[i
].path
[PATH_MAX
- 1] = '\0';
1740 strncpy(sessions
[i
].name
, session
->name
, NAME_MAX
);
1741 sessions
[i
].name
[NAME_MAX
- 1] = '\0';
1747 * Fill lttng_channel array of all channels.
1749 static void list_lttng_channels(struct ltt_session
*session
,
1750 struct lttng_channel
*channels
)
1753 struct ltt_kernel_channel
*kchan
;
1755 DBG("Listing channels for session %s", session
->name
);
1757 /* Kernel channels */
1758 if (session
->kernel_session
!= NULL
) {
1759 cds_list_for_each_entry(kchan
,
1760 &session
->kernel_session
->channel_list
.head
, list
) {
1761 /* Copy lttng_channel struct to array */
1762 memcpy(&channels
[i
], kchan
->channel
, sizeof(struct lttng_channel
));
1763 channels
[i
].enabled
= kchan
->enabled
;
1768 /* TODO: Missing UST listing */
1772 * Fill lttng_event array of all events in the channel.
1774 static void list_lttng_events(struct ltt_kernel_channel
*kchan
,
1775 struct lttng_event
*events
)
1778 * TODO: This is ONLY kernel. Need UST support.
1781 struct ltt_kernel_event
*event
;
1783 DBG("Listing events for channel %s", kchan
->channel
->name
);
1785 /* Kernel channels */
1786 cds_list_for_each_entry(event
, &kchan
->events_list
.head
, list
) {
1787 strncpy(events
[i
].name
, event
->event
->name
, LTTNG_SYMBOL_NAME_LEN
);
1788 events
[i
].name
[LTTNG_SYMBOL_NAME_LEN
- 1] = '\0';
1789 events
[i
].enabled
= event
->enabled
;
1790 switch (event
->event
->instrumentation
) {
1791 case LTTNG_KERNEL_TRACEPOINT
:
1792 events
[i
].type
= LTTNG_EVENT_TRACEPOINT
;
1794 case LTTNG_KERNEL_KPROBE
:
1795 case LTTNG_KERNEL_KRETPROBE
:
1796 events
[i
].type
= LTTNG_EVENT_PROBE
;
1797 memcpy(&events
[i
].attr
.probe
, &event
->event
->u
.kprobe
,
1798 sizeof(struct lttng_kernel_kprobe
));
1800 case LTTNG_KERNEL_FUNCTION
:
1801 events
[i
].type
= LTTNG_EVENT_FUNCTION
;
1802 memcpy(&events
[i
].attr
.ftrace
, &event
->event
->u
.ftrace
,
1803 sizeof(struct lttng_kernel_function
));
1805 case LTTNG_KERNEL_NOOP
:
1806 events
[i
].type
= LTTNG_EVENT_NOOP
;
1808 case LTTNG_KERNEL_SYSCALL
:
1809 events
[i
].type
= LTTNG_EVENT_SYSCALL
;
1811 case LTTNG_KERNEL_ALL
:
1820 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1822 static int cmd_disable_channel(struct ltt_session
*session
,
1823 int domain
, char *channel_name
)
1828 case LTTNG_DOMAIN_KERNEL
:
1829 ret
= channel_kernel_disable(session
->kernel_session
,
1831 if (ret
!= LTTCOMM_OK
) {
1835 kernel_wait_quiescent(kernel_tracer_fd
);
1837 case LTTNG_DOMAIN_UST_PID
:
1840 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
1851 * Copy channel from attributes and set it in the application channel list.
1853 static int copy_ust_channel_to_app(struct ltt_ust_session
*usess
,
1854 struct lttng_channel
*attr
, struct ust_app
*app
)
1857 struct ltt_ust_channel
*uchan
, *new_chan
;
1859 uchan
= trace_ust_get_channel_by_name(attr
->name
, usess
);
1860 if (uchan
== NULL
) {
1861 ret
= LTTCOMM_FATAL
;
1865 new_chan
= trace_ust_create_channel(attr
, usess
->path
);
1866 if (new_chan
== NULL
) {
1867 PERROR("malloc ltt_ust_channel");
1868 ret
= LTTCOMM_FATAL
;
1872 ret
= channel_ust_copy(new_chan
, uchan
);
1874 ret
= LTTCOMM_FATAL
;
1878 /* Add channel to the ust app channel list */
1879 cds_list_add(&new_chan
->list
, &app
->channels
.head
);
1880 app
->channels
.count
++;
1887 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1889 static int cmd_enable_channel(struct ltt_session
*session
,
1890 struct lttng_domain
*domain
, struct lttng_channel
*attr
)
1894 switch (domain
->type
) {
1895 case LTTNG_DOMAIN_KERNEL
:
1897 struct ltt_kernel_channel
*kchan
;
1899 kchan
= trace_kernel_get_channel_by_name(attr
->name
,
1900 session
->kernel_session
);
1901 if (kchan
== NULL
) {
1902 ret
= channel_kernel_create(session
->kernel_session
,
1903 attr
, kernel_poll_pipe
[1]);
1905 ret
= channel_kernel_enable(session
->kernel_session
, kchan
);
1908 if (ret
!= LTTCOMM_OK
) {
1912 kernel_wait_quiescent(kernel_tracer_fd
);
1915 case LTTNG_DOMAIN_UST_PID
:
1918 struct ltt_ust_channel
*uchan
;
1919 struct ltt_ust_session
*usess
;
1920 struct ust_app
*app
;
1922 usess
= trace_ust_get_session_by_pid(&session
->ust_session_list
,
1924 if (usess
== NULL
) {
1925 ret
= LTTCOMM_UST_CHAN_NOT_FOUND
;
1929 app
= ust_app_get_by_pid(domain
->attr
.pid
);
1931 ret
= LTTCOMM_APP_NOT_FOUND
;
1936 uchan
= trace_ust_get_channel_by_name(attr
->name
, usess
);
1937 if (uchan
== NULL
) {
1938 ret
= channel_ust_create(usess
, attr
, sock
);
1940 ret
= channel_ust_enable(usess
, uchan
, sock
);
1943 if (ret
!= LTTCOMM_OK
) {
1947 ret
= copy_ust_channel_to_app(usess
, attr
, app
);
1948 if (ret
!= LTTCOMM_OK
) {
1952 DBG("UST channel %s created for app sock %d with pid %d",
1953 attr
->name
, app
->sock
, domain
->attr
.pid
);
1957 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
1968 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1970 static int cmd_disable_event(struct ltt_session
*session
, int domain
,
1971 char *channel_name
, char *event_name
)
1974 struct ltt_kernel_channel
*kchan
;
1977 case LTTNG_DOMAIN_KERNEL
:
1978 kchan
= trace_kernel_get_channel_by_name(channel_name
,
1979 session
->kernel_session
);
1980 if (kchan
== NULL
) {
1981 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
1985 ret
= event_kernel_disable_tracepoint(session
->kernel_session
, kchan
, event_name
);
1986 if (ret
!= LTTCOMM_OK
) {
1990 kernel_wait_quiescent(kernel_tracer_fd
);
1993 /* TODO: Userspace tracing */
1994 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2005 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2007 static int cmd_disable_event_all(struct ltt_session
*session
, int domain
,
2011 struct ltt_kernel_channel
*kchan
;
2014 case LTTNG_DOMAIN_KERNEL
:
2015 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2016 session
->kernel_session
);
2017 if (kchan
== NULL
) {
2018 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
2022 ret
= event_kernel_disable_all(session
->kernel_session
, kchan
);
2023 if (ret
!= LTTCOMM_OK
) {
2027 kernel_wait_quiescent(kernel_tracer_fd
);
2030 /* TODO: Userspace tracing */
2031 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2042 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2044 static int cmd_add_context(struct ltt_session
*session
, int domain
,
2045 char *channel_name
, char *event_name
, struct lttng_event_context
*ctx
)
2050 case LTTNG_DOMAIN_KERNEL
:
2051 /* Add kernel context to kernel tracer */
2052 ret
= context_kernel_add(session
->kernel_session
, ctx
,
2053 event_name
, channel_name
);
2054 if (ret
!= LTTCOMM_OK
) {
2060 /* TODO: Userspace tracing */
2061 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2072 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2074 static int cmd_enable_event(struct ltt_session
*session
, int domain
,
2075 char *channel_name
, struct lttng_event
*event
)
2078 struct ltt_kernel_channel
*kchan
;
2081 case LTTNG_DOMAIN_KERNEL
:
2082 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2083 session
->kernel_session
);
2084 if (kchan
== NULL
) {
2085 /* This call will notify the kernel thread */
2086 ret
= channel_kernel_create(session
->kernel_session
,
2087 NULL
, kernel_poll_pipe
[1]);
2088 if (ret
!= LTTCOMM_OK
) {
2093 /* Get the newly created kernel channel pointer */
2094 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2095 session
->kernel_session
);
2096 if (kchan
== NULL
) {
2097 /* This sould not happen... */
2098 ret
= LTTCOMM_FATAL
;
2102 ret
= event_kernel_enable_tracepoint(session
->kernel_session
, kchan
, event
);
2103 if (ret
!= LTTCOMM_OK
) {
2107 kernel_wait_quiescent(kernel_tracer_fd
);
2110 /* TODO: Userspace tracing */
2111 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2122 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2124 static int cmd_enable_event_all(struct ltt_session
*session
, int domain
,
2125 char *channel_name
, int event_type
)
2128 struct ltt_kernel_channel
*kchan
;
2131 case LTTNG_DOMAIN_KERNEL
:
2132 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2133 session
->kernel_session
);
2134 if (kchan
== NULL
) {
2135 /* This call will notify the kernel thread */
2136 ret
= channel_kernel_create(session
->kernel_session
, NULL
,
2137 kernel_poll_pipe
[1]);
2138 if (ret
!= LTTCOMM_OK
) {
2143 /* Get the newly created kernel channel pointer */
2144 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2145 session
->kernel_session
);
2146 if (kchan
== NULL
) {
2147 /* This sould not happen... */
2148 ret
= LTTCOMM_FATAL
;
2152 switch (event_type
) {
2153 case LTTNG_KERNEL_SYSCALL
:
2154 ret
= event_kernel_enable_all_syscalls(session
->kernel_session
,
2155 kchan
, kernel_tracer_fd
);
2157 case LTTNG_KERNEL_TRACEPOINT
:
2159 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2160 * events already registered to the channel.
2162 ret
= event_kernel_enable_all_tracepoints(session
->kernel_session
,
2163 kchan
, kernel_tracer_fd
);
2165 case LTTNG_KERNEL_ALL
:
2166 /* Enable syscalls and tracepoints */
2167 ret
= event_kernel_enable_all(session
->kernel_session
,
2168 kchan
, kernel_tracer_fd
);
2171 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2174 if (ret
!= LTTCOMM_OK
) {
2178 kernel_wait_quiescent(kernel_tracer_fd
);
2181 /* TODO: Userspace tracing */
2182 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2193 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2195 static ssize_t
cmd_list_tracepoints(int domain
, struct lttng_event
**events
)
2198 ssize_t nb_events
= 0;
2201 case LTTNG_DOMAIN_KERNEL
:
2202 nb_events
= kernel_list_events(kernel_tracer_fd
, events
);
2203 if (nb_events
< 0) {
2204 ret
= LTTCOMM_KERN_LIST_FAIL
;
2209 /* TODO: Userspace listing */
2210 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2217 /* Return negative value to differentiate return code */
2222 * Command LTTNG_START_TRACE processed by the client thread.
2224 static int cmd_start_trace(struct ltt_session
*session
)
2227 struct ltt_kernel_channel
*kchan
;
2228 struct ltt_kernel_session
*ksession
;
2231 ksession
= session
->kernel_session
;
2233 /* Kernel tracing */
2234 if (ksession
!= NULL
) {
2235 /* Open kernel metadata */
2236 if (ksession
->metadata
== NULL
) {
2237 ret
= kernel_open_metadata(ksession
, ksession
->trace_path
);
2239 ret
= LTTCOMM_KERN_META_FAIL
;
2244 /* Open kernel metadata stream */
2245 if (ksession
->metadata_stream_fd
== 0) {
2246 ret
= kernel_open_metadata_stream(ksession
);
2248 ERR("Kernel create metadata stream failed");
2249 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2254 /* For each channel */
2255 cds_list_for_each_entry(kchan
, &ksession
->channel_list
.head
, list
) {
2256 if (kchan
->stream_count
== 0) {
2257 ret
= kernel_open_channel_stream(kchan
);
2259 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2262 /* Update the stream global counter */
2263 ksession
->stream_count_global
+= ret
;
2267 /* Setup kernel consumer socket and send fds to it */
2268 ret
= init_kernel_tracing(ksession
);
2270 ret
= LTTCOMM_KERN_START_FAIL
;
2274 /* This start the kernel tracing */
2275 ret
= kernel_start_session(ksession
);
2277 ret
= LTTCOMM_KERN_START_FAIL
;
2281 /* Quiescent wait after starting trace */
2282 kernel_wait_quiescent(kernel_tracer_fd
);
2285 /* TODO: Start all UST traces */
2294 * Command LTTNG_STOP_TRACE processed by the client thread.
2296 static int cmd_stop_trace(struct ltt_session
*session
)
2299 struct ltt_kernel_channel
*kchan
;
2300 struct ltt_kernel_session
*ksession
;
2303 ksession
= session
->kernel_session
;
2306 if (ksession
!= NULL
) {
2307 DBG("Stop kernel tracing");
2309 /* Flush all buffers before stopping */
2310 ret
= kernel_metadata_flush_buffer(ksession
->metadata_stream_fd
);
2312 ERR("Kernel metadata flush failed");
2315 cds_list_for_each_entry(kchan
, &ksession
->channel_list
.head
, list
) {
2316 ret
= kernel_flush_buffer(kchan
);
2318 ERR("Kernel flush buffer error");
2322 ret
= kernel_stop_session(ksession
);
2324 ret
= LTTCOMM_KERN_STOP_FAIL
;
2328 kernel_wait_quiescent(kernel_tracer_fd
);
2331 /* TODO : User-space tracer */
2340 * Command LTTNG_CREATE_SESSION processed by the client thread.
2342 static int cmd_create_session(char *name
, char *path
)
2346 ret
= session_create(name
, path
);
2347 if (ret
!= LTTCOMM_OK
) {
2358 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2360 static int cmd_destroy_session(struct ltt_session
*session
, char *name
)
2364 /* Clean kernel session teardown */
2365 teardown_kernel_session(session
);
2368 * Must notify the kernel thread here to update it's poll setin order
2369 * to remove the channel(s)' fd just destroyed.
2371 ret
= notify_thread_pipe(kernel_poll_pipe
[1]);
2373 perror("write kernel poll pipe");
2376 ret
= session_destroy(session
);
2382 * Command LTTNG_CALIBRATE processed by the client thread.
2384 static int cmd_calibrate(int domain
, struct lttng_calibrate
*calibrate
)
2389 case LTTNG_DOMAIN_KERNEL
:
2391 struct lttng_kernel_calibrate kcalibrate
;
2393 kcalibrate
.type
= calibrate
->type
;
2394 ret
= kernel_calibrate(kernel_tracer_fd
, &kcalibrate
);
2396 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2402 /* TODO: Userspace tracing */
2403 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2414 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2416 static int cmd_register_consumer(struct ltt_session
*session
, int domain
,
2422 case LTTNG_DOMAIN_KERNEL
:
2423 /* Can't register a consumer if there is already one */
2424 if (session
->kernel_session
->consumer_fd
!= 0) {
2425 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
2429 sock
= lttcomm_connect_unix_sock(sock_path
);
2431 ret
= LTTCOMM_CONNECT_FAIL
;
2435 session
->kernel_session
->consumer_fd
= sock
;
2438 /* TODO: Userspace tracing */
2439 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2450 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2452 static ssize_t
cmd_list_domains(struct ltt_session
*session
,
2453 struct lttng_domain
**domains
)
2458 if (session
->kernel_session
!= NULL
) {
2462 nb_dom
+= session
->ust_session_list
.count
;
2464 *domains
= malloc(nb_dom
* sizeof(struct lttng_domain
));
2465 if (*domains
== NULL
) {
2466 ret
= -LTTCOMM_FATAL
;
2470 (*domains
)[0].type
= LTTNG_DOMAIN_KERNEL
;
2472 /* TODO: User-space tracer domain support */
2481 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2483 static ssize_t
cmd_list_channels(struct ltt_session
*session
,
2484 struct lttng_channel
**channels
)
2487 ssize_t nb_chan
= 0;
2489 if (session
->kernel_session
!= NULL
) {
2490 nb_chan
+= session
->kernel_session
->channel_count
;
2493 *channels
= malloc(nb_chan
* sizeof(struct lttng_channel
));
2494 if (*channels
== NULL
) {
2495 ret
= -LTTCOMM_FATAL
;
2499 list_lttng_channels(session
, *channels
);
2508 * Command LTTNG_LIST_EVENTS processed by the client thread.
2510 static ssize_t
cmd_list_events(struct ltt_session
*session
,
2511 char *channel_name
, struct lttng_event
**events
)
2514 ssize_t nb_event
= 0;
2515 struct ltt_kernel_channel
*kchan
= NULL
;
2517 if (session
->kernel_session
!= NULL
) {
2518 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2519 session
->kernel_session
);
2520 if (kchan
== NULL
) {
2521 ret
= -LTTCOMM_KERN_CHAN_NOT_FOUND
;
2524 nb_event
+= kchan
->event_count
;
2527 *events
= malloc(nb_event
* sizeof(struct lttng_event
));
2528 if (*events
== NULL
) {
2529 ret
= -LTTCOMM_FATAL
;
2533 list_lttng_events(kchan
, *events
);
2535 /* TODO: User-space tracer support */
2544 * Process the command requested by the lttng client within the command
2545 * context structure. This function make sure that the return structure (llm)
2546 * is set and ready for transmission before returning.
2548 * Return any error encountered or 0 for success.
2550 static int process_client_msg(struct command_ctx
*cmd_ctx
)
2552 int ret
= LTTCOMM_OK
;
2553 int need_tracing_session
= 1;
2555 DBG("Processing client command %d", cmd_ctx
->lsm
->cmd_type
);
2558 * Check for command that don't needs to allocate a returned payload. We do
2559 * this here so we don't have to make the call for no payload at each
2562 switch(cmd_ctx
->lsm
->cmd_type
) {
2563 case LTTNG_LIST_SESSIONS
:
2564 case LTTNG_LIST_TRACEPOINTS
:
2565 case LTTNG_LIST_DOMAINS
:
2566 case LTTNG_LIST_CHANNELS
:
2567 case LTTNG_LIST_EVENTS
:
2570 /* Setup lttng message with no payload */
2571 ret
= setup_lttng_msg(cmd_ctx
, 0);
2573 /* This label does not try to unlock the session */
2574 goto init_setup_error
;
2578 /* Commands that DO NOT need a session. */
2579 switch (cmd_ctx
->lsm
->cmd_type
) {
2580 case LTTNG_CALIBRATE
:
2581 case LTTNG_CREATE_SESSION
:
2582 case LTTNG_LIST_SESSIONS
:
2583 case LTTNG_LIST_TRACEPOINTS
:
2584 need_tracing_session
= 0;
2587 DBG("Getting session %s by name", cmd_ctx
->lsm
->session
.name
);
2588 cmd_ctx
->session
= session_find_by_name(cmd_ctx
->lsm
->session
.name
);
2589 if (cmd_ctx
->session
== NULL
) {
2590 if (cmd_ctx
->lsm
->session
.name
!= NULL
) {
2591 ret
= LTTCOMM_SESS_NOT_FOUND
;
2593 /* If no session name specified */
2594 ret
= LTTCOMM_SELECT_SESS
;
2598 /* Acquire lock for the session */
2599 session_lock(cmd_ctx
->session
);
2605 * Check domain type for specific "pre-action".
2607 switch (cmd_ctx
->lsm
->domain
.type
) {
2608 case LTTNG_DOMAIN_KERNEL
:
2609 /* Kernel tracer check */
2610 if (kernel_tracer_fd
== 0) {
2611 /* Basically, load kernel tracer modules */
2612 init_kernel_tracer();
2613 if (kernel_tracer_fd
== 0) {
2614 ret
= LTTCOMM_KERN_NA
;
2619 /* Need a session for kernel command */
2620 if (need_tracing_session
) {
2621 if (cmd_ctx
->session
->kernel_session
== NULL
) {
2622 ret
= create_kernel_session(cmd_ctx
->session
);
2624 ret
= LTTCOMM_KERN_SESS_FAIL
;
2629 /* Start the kernel consumer daemon */
2630 if (kconsumerd_pid
== 0 &&
2631 cmd_ctx
->lsm
->cmd_type
!= LTTNG_REGISTER_CONSUMER
) {
2632 ret
= start_kconsumerd();
2634 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
2640 case LTTNG_DOMAIN_UST_PID
:
2642 struct ltt_ust_session
*usess
;
2644 if (need_tracing_session
) {
2645 usess
= trace_ust_get_session_by_pid(
2646 &cmd_ctx
->session
->ust_session_list
,
2647 cmd_ctx
->lsm
->domain
.attr
.pid
);
2648 if (usess
== NULL
) {
2649 ret
= create_ust_session(cmd_ctx
->session
,
2650 &cmd_ctx
->lsm
->domain
);
2651 if (ret
!= LTTCOMM_OK
) {
2659 /* TODO Userspace tracer */
2663 /* Process by command type */
2664 switch (cmd_ctx
->lsm
->cmd_type
) {
2665 case LTTNG_ADD_CONTEXT
:
2667 ret
= cmd_add_context(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2668 cmd_ctx
->lsm
->u
.context
.channel_name
,
2669 cmd_ctx
->lsm
->u
.context
.event_name
,
2670 &cmd_ctx
->lsm
->u
.context
.ctx
);
2673 case LTTNG_DISABLE_CHANNEL
:
2675 ret
= cmd_disable_channel(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2676 cmd_ctx
->lsm
->u
.disable
.channel_name
);
2679 case LTTNG_DISABLE_EVENT
:
2681 ret
= cmd_disable_event(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2682 cmd_ctx
->lsm
->u
.disable
.channel_name
,
2683 cmd_ctx
->lsm
->u
.disable
.name
);
2687 case LTTNG_DISABLE_ALL_EVENT
:
2689 DBG("Disabling all kernel event");
2691 ret
= cmd_disable_event_all(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2692 cmd_ctx
->lsm
->u
.disable
.channel_name
);
2695 case LTTNG_ENABLE_CHANNEL
:
2697 ret
= cmd_enable_channel(cmd_ctx
->session
, &cmd_ctx
->lsm
->domain
,
2698 &cmd_ctx
->lsm
->u
.channel
.chan
);
2701 case LTTNG_ENABLE_EVENT
:
2703 ret
= cmd_enable_event(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2704 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2705 &cmd_ctx
->lsm
->u
.enable
.event
);
2708 case LTTNG_ENABLE_ALL_EVENT
:
2710 DBG("Enabling all kernel event");
2712 ret
= cmd_enable_event_all(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2713 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2714 cmd_ctx
->lsm
->u
.enable
.event
.type
);
2717 case LTTNG_LIST_TRACEPOINTS
:
2719 struct lttng_event
*events
;
2722 nb_events
= cmd_list_tracepoints(cmd_ctx
->lsm
->domain
.type
, &events
);
2723 if (nb_events
< 0) {
2729 * Setup lttng message with payload size set to the event list size in
2730 * bytes and then copy list into the llm payload.
2732 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_event
) * nb_events
);
2738 /* Copy event list into message payload */
2739 memcpy(cmd_ctx
->llm
->payload
, events
,
2740 sizeof(struct lttng_event
) * nb_events
);
2747 case LTTNG_START_TRACE
:
2749 ret
= cmd_start_trace(cmd_ctx
->session
);
2752 case LTTNG_STOP_TRACE
:
2754 ret
= cmd_stop_trace(cmd_ctx
->session
);
2757 case LTTNG_CREATE_SESSION
:
2759 tracepoint(create_session_start
);
2760 ret
= cmd_create_session(cmd_ctx
->lsm
->session
.name
,
2761 cmd_ctx
->lsm
->session
.path
);
2762 tracepoint(create_session_end
);
2765 case LTTNG_DESTROY_SESSION
:
2767 tracepoint(destroy_session_start
);
2768 ret
= cmd_destroy_session(cmd_ctx
->session
,
2769 cmd_ctx
->lsm
->session
.name
);
2770 tracepoint(destroy_session_end
);
2773 case LTTNG_LIST_DOMAINS
:
2776 struct lttng_domain
*domains
;
2778 nb_dom
= cmd_list_domains(cmd_ctx
->session
, &domains
);
2784 ret
= setup_lttng_msg(cmd_ctx
, nb_dom
* sizeof(struct lttng_domain
));
2789 /* Copy event list into message payload */
2790 memcpy(cmd_ctx
->llm
->payload
, domains
,
2791 nb_dom
* sizeof(struct lttng_domain
));
2798 case LTTNG_LIST_CHANNELS
:
2801 struct lttng_channel
*channels
;
2803 nb_chan
= cmd_list_channels(cmd_ctx
->session
, &channels
);
2809 ret
= setup_lttng_msg(cmd_ctx
, nb_chan
* sizeof(struct lttng_channel
));
2814 /* Copy event list into message payload */
2815 memcpy(cmd_ctx
->llm
->payload
, channels
,
2816 nb_chan
* sizeof(struct lttng_channel
));
2823 case LTTNG_LIST_EVENTS
:
2826 struct lttng_event
*events
= NULL
;
2828 nb_event
= cmd_list_events(cmd_ctx
->session
,
2829 cmd_ctx
->lsm
->u
.list
.channel_name
, &events
);
2835 ret
= setup_lttng_msg(cmd_ctx
, nb_event
* sizeof(struct lttng_event
));
2840 /* Copy event list into message payload */
2841 memcpy(cmd_ctx
->llm
->payload
, events
,
2842 nb_event
* sizeof(struct lttng_event
));
2849 case LTTNG_LIST_SESSIONS
:
2851 session_lock_list();
2853 if (session_list_ptr
->count
== 0) {
2854 ret
= LTTCOMM_NO_SESSION
;
2855 session_unlock_list();
2859 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_session
) *
2860 session_list_ptr
->count
);
2862 session_unlock_list();
2866 /* Filled the session array */
2867 list_lttng_sessions((struct lttng_session
*)(cmd_ctx
->llm
->payload
));
2869 session_unlock_list();
2874 case LTTNG_CALIBRATE
:
2876 ret
= cmd_calibrate(cmd_ctx
->lsm
->domain
.type
,
2877 &cmd_ctx
->lsm
->u
.calibrate
);
2880 case LTTNG_REGISTER_CONSUMER
:
2882 ret
= cmd_register_consumer(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2883 cmd_ctx
->lsm
->u
.reg
.path
);
2892 if (cmd_ctx
->llm
== NULL
) {
2893 DBG("Missing llm structure. Allocating one.");
2894 if (setup_lttng_msg(cmd_ctx
, 0) < 0) {
2898 /* Set return code */
2899 cmd_ctx
->llm
->ret_code
= ret
;
2901 if (cmd_ctx
->session
) {
2902 session_unlock(cmd_ctx
->session
);
2909 * This thread manage all clients request using the unix client socket for
2912 static void *thread_manage_clients(void *data
)
2914 int sock
= 0, ret
, i
, pollfd
;
2915 uint32_t revents
, nb_fd
;
2916 struct command_ctx
*cmd_ctx
= NULL
;
2917 struct lttng_poll_event events
;
2919 tracepoint(sessiond_th_cli_start
);
2921 DBG("[thread] Manage client started");
2923 ret
= lttcomm_listen_unix_sock(client_sock
);
2929 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2930 * more will be added to this poll set.
2932 ret
= create_thread_poll_set(&events
, 2);
2937 /* Add the application registration socket */
2938 ret
= lttng_poll_add(&events
, client_sock
, LPOLLIN
| LPOLLPRI
);
2944 * Notify parent pid that we are ready to accept command for client side.
2946 if (opt_sig_parent
) {
2947 kill(ppid
, SIGCHLD
);
2951 DBG("Accepting client command ...");
2953 tracepoint(sessiond_th_cli_poll
);
2955 nb_fd
= LTTNG_POLL_GETNB(&events
);
2957 /* Inifinite blocking call, waiting for transmission */
2958 ret
= lttng_poll_wait(&events
, -1);
2963 for (i
= 0; i
< nb_fd
; i
++) {
2964 /* Fetch once the poll data */
2965 revents
= LTTNG_POLL_GETEV(&events
, i
);
2966 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2968 /* Thread quit pipe has been closed. Killing thread. */
2969 ret
= check_thread_quit_pipe(pollfd
, revents
);
2974 /* Event on the registration socket */
2975 if (pollfd
== client_sock
) {
2976 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
2977 ERR("Client socket poll error");
2983 DBG("Wait for client response");
2985 sock
= lttcomm_accept_unix_sock(client_sock
);
2990 /* Allocate context command to process the client request */
2991 cmd_ctx
= malloc(sizeof(struct command_ctx
));
2992 if (cmd_ctx
== NULL
) {
2993 perror("malloc cmd_ctx");
2997 /* Allocate data buffer for reception */
2998 cmd_ctx
->lsm
= malloc(sizeof(struct lttcomm_session_msg
));
2999 if (cmd_ctx
->lsm
== NULL
) {
3000 perror("malloc cmd_ctx->lsm");
3004 cmd_ctx
->llm
= NULL
;
3005 cmd_ctx
->session
= NULL
;
3008 * Data is received from the lttng client. The struct
3009 * lttcomm_session_msg (lsm) contains the command and data request of
3012 DBG("Receiving data from client ...");
3013 ret
= lttcomm_recv_unix_sock(sock
, cmd_ctx
->lsm
,
3014 sizeof(struct lttcomm_session_msg
));
3016 DBG("Nothing recv() from client... continuing");
3022 // TODO: Validate cmd_ctx including sanity check for
3023 // security purpose.
3026 * This function dispatch the work to the kernel or userspace tracer
3027 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3028 * informations for the client. The command context struct contains
3029 * everything this function may needs.
3031 ret
= process_client_msg(cmd_ctx
);
3034 * TODO: Inform client somehow of the fatal error. At
3035 * this point, ret < 0 means that a malloc failed
3036 * (ENOMEM). Error detected but still accept command.
3038 clean_command_ctx(&cmd_ctx
);
3042 DBG("Sending response (size: %d, retcode: %s)",
3043 cmd_ctx
->lttng_msg_size
,
3044 lttng_get_readable_code(-cmd_ctx
->llm
->ret_code
));
3045 ret
= send_unix_sock(sock
, cmd_ctx
->llm
, cmd_ctx
->lttng_msg_size
);
3047 ERR("Failed to send data back to client");
3050 clean_command_ctx(&cmd_ctx
);
3052 /* End of transmission */
3057 DBG("Client thread dying");
3058 unlink(client_unix_sock_path
);
3062 lttng_poll_clean(&events
);
3063 clean_command_ctx(&cmd_ctx
);
3069 * usage function on stderr
3071 static void usage(void)
3073 fprintf(stderr
, "Usage: %s OPTIONS\n\nOptions:\n", progname
);
3074 fprintf(stderr
, " -h, --help Display this usage.\n");
3075 fprintf(stderr
, " -c, --client-sock PATH Specify path for the client unix socket\n");
3076 fprintf(stderr
, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3077 fprintf(stderr
, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3078 fprintf(stderr
, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3079 fprintf(stderr
, " -d, --daemonize Start as a daemon.\n");
3080 fprintf(stderr
, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3081 fprintf(stderr
, " -V, --version Show version number.\n");
3082 fprintf(stderr
, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3083 fprintf(stderr
, " -q, --quiet No output at all.\n");
3084 fprintf(stderr
, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3085 fprintf(stderr
, " --verbose-kconsumerd Verbose mode for kconsumerd. Activate DBG() macro.\n");
3089 * daemon argument parsing
3091 static int parse_args(int argc
, char **argv
)
3095 static struct option long_options
[] = {
3096 { "client-sock", 1, 0, 'c' },
3097 { "apps-sock", 1, 0, 'a' },
3098 { "kconsumerd-cmd-sock", 1, 0, 0 },
3099 { "kconsumerd-err-sock", 1, 0, 0 },
3100 { "daemonize", 0, 0, 'd' },
3101 { "sig-parent", 0, 0, 'S' },
3102 { "help", 0, 0, 'h' },
3103 { "group", 1, 0, 'g' },
3104 { "version", 0, 0, 'V' },
3105 { "quiet", 0, 0, 'q' },
3106 { "verbose", 0, 0, 'v' },
3107 { "verbose-kconsumerd", 0, 0, 'Z' },
3112 int option_index
= 0;
3113 c
= getopt_long(argc
, argv
, "dhqvVS" "a:c:g:s:E:C:Z",
3114 long_options
, &option_index
);
3121 fprintf(stderr
, "option %s", long_options
[option_index
].name
);
3123 fprintf(stderr
, " with arg %s\n", optarg
);
3127 snprintf(client_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3130 snprintf(apps_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3136 opt_tracing_group
= strdup(optarg
);
3142 fprintf(stdout
, "%s\n", VERSION
);
3148 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3151 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3157 /* Verbose level can increase using multiple -v */
3161 opt_verbose_kconsumerd
+= 1;
3164 /* Unknown option or other error.
3165 * Error is printed by getopt, just return */
3174 * Creates the two needed socket by the daemon.
3175 * apps_sock - The communication socket for all UST apps.
3176 * client_sock - The communication of the cli tool (lttng).
3178 static int init_daemon_socket(void)
3183 old_umask
= umask(0);
3185 /* Create client tool unix socket */
3186 client_sock
= lttcomm_create_unix_sock(client_unix_sock_path
);
3187 if (client_sock
< 0) {
3188 ERR("Create unix sock failed: %s", client_unix_sock_path
);
3193 /* File permission MUST be 660 */
3194 ret
= chmod(client_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3196 ERR("Set file permissions failed: %s", client_unix_sock_path
);
3201 /* Create the application unix socket */
3202 apps_sock
= lttcomm_create_unix_sock(apps_unix_sock_path
);
3203 if (apps_sock
< 0) {
3204 ERR("Create unix sock failed: %s", apps_unix_sock_path
);
3209 /* File permission MUST be 666 */
3210 ret
= chmod(apps_unix_sock_path
,
3211 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
| S_IROTH
| S_IWOTH
);
3213 ERR("Set file permissions failed: %s", apps_unix_sock_path
);
3224 * Check if the global socket is available, and if a daemon is answering at the
3225 * other side. If yes, error is returned.
3227 static int check_existing_daemon(void)
3229 if (access(client_unix_sock_path
, F_OK
) < 0 &&
3230 access(apps_unix_sock_path
, F_OK
) < 0) {
3234 /* Is there anybody out there ? */
3235 if (lttng_session_daemon_alive()) {
3243 * Set the tracing group gid onto the client socket.
3245 * Race window between mkdir and chown is OK because we are going from more
3246 * permissive (root.root) to les permissive (root.tracing).
3248 static int set_permissions(void)
3253 gid
= allowed_group();
3256 WARN("No tracing group detected");
3259 ERR("Missing tracing group. Aborting execution.");
3265 /* Set lttng run dir */
3266 ret
= chown(LTTNG_RUNDIR
, 0, gid
);
3268 ERR("Unable to set group on " LTTNG_RUNDIR
);
3272 /* lttng client socket path */
3273 ret
= chown(client_unix_sock_path
, 0, gid
);
3275 ERR("Unable to set group on %s", client_unix_sock_path
);
3279 /* kconsumerd error socket path */
3280 ret
= chown(kconsumerd_err_unix_sock_path
, 0, gid
);
3282 ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path
);
3286 DBG("All permissions are set");
3293 * Create the pipe used to wake up the kernel thread.
3295 static int create_kernel_poll_pipe(void)
3297 return pipe2(kernel_poll_pipe
, O_CLOEXEC
);
3301 * Create the application command pipe to wake thread_manage_apps.
3303 static int create_apps_cmd_pipe(void)
3305 return pipe2(apps_cmd_pipe
, O_CLOEXEC
);
3309 * Create the lttng run directory needed for all global sockets and pipe.
3311 static int create_lttng_rundir(void)
3315 ret
= mkdir(LTTNG_RUNDIR
, S_IRWXU
| S_IRWXG
);
3317 if (errno
!= EEXIST
) {
3318 ERR("Unable to create " LTTNG_RUNDIR
);
3330 * Setup sockets and directory needed by the kconsumerd communication with the
3333 static int set_kconsumerd_sockets(void)
3337 if (strlen(kconsumerd_err_unix_sock_path
) == 0) {
3338 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
,
3339 KCONSUMERD_ERR_SOCK_PATH
);
3342 if (strlen(kconsumerd_cmd_unix_sock_path
) == 0) {
3343 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
,
3344 KCONSUMERD_CMD_SOCK_PATH
);
3347 ret
= mkdir(KCONSUMERD_PATH
, S_IRWXU
| S_IRWXG
);
3349 if (errno
!= EEXIST
) {
3350 ERR("Failed to create " KCONSUMERD_PATH
);
3356 /* Create the kconsumerd error unix socket */
3357 kconsumerd_err_sock
=
3358 lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path
);
3359 if (kconsumerd_err_sock
< 0) {
3360 ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path
);
3365 /* File permission MUST be 660 */
3366 ret
= chmod(kconsumerd_err_unix_sock_path
,
3367 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3369 ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path
);
3379 * Signal handler for the daemon
3381 * Simply stop all worker threads, leaving main() return gracefully after
3382 * joining all threads and calling cleanup().
3384 static void sighandler(int sig
)
3388 DBG("SIGPIPE catched");
3391 DBG("SIGINT catched");
3395 DBG("SIGTERM catched");
3404 * Setup signal handler for :
3405 * SIGINT, SIGTERM, SIGPIPE
3407 static int set_signal_handler(void)
3410 struct sigaction sa
;
3413 if ((ret
= sigemptyset(&sigset
)) < 0) {
3414 perror("sigemptyset");
3418 sa
.sa_handler
= sighandler
;
3419 sa
.sa_mask
= sigset
;
3421 if ((ret
= sigaction(SIGTERM
, &sa
, NULL
)) < 0) {
3422 perror("sigaction");
3426 if ((ret
= sigaction(SIGINT
, &sa
, NULL
)) < 0) {
3427 perror("sigaction");
3431 if ((ret
= sigaction(SIGPIPE
, &sa
, NULL
)) < 0) {
3432 perror("sigaction");
3436 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3442 * Set open files limit to unlimited. This daemon can open a large number of
3443 * file descriptors in order to consumer multiple kernel traces.
3445 static void set_ulimit(void)
3450 /* The kernel does not allowed an infinite limit for open files */
3451 lim
.rlim_cur
= 65535;
3452 lim
.rlim_max
= 65535;
3454 ret
= setrlimit(RLIMIT_NOFILE
, &lim
);
3456 perror("failed to set open files limit");
3463 int main(int argc
, char **argv
)
3467 const char *home_path
;
3469 tracepoint(sessiond_boot_start
);
3471 /* Create thread quit pipe */
3472 if ((ret
= init_thread_quit_pipe()) < 0) {
3476 /* Parse arguments */
3478 if ((ret
= parse_args(argc
, argv
) < 0)) {
3491 /* Check if daemon is UID = 0 */
3492 is_root
= !getuid();
3495 ret
= create_lttng_rundir();
3500 if (strlen(apps_unix_sock_path
) == 0) {
3501 snprintf(apps_unix_sock_path
, PATH_MAX
,
3502 DEFAULT_GLOBAL_APPS_UNIX_SOCK
);
3505 if (strlen(client_unix_sock_path
) == 0) {
3506 snprintf(client_unix_sock_path
, PATH_MAX
,
3507 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
);
3510 /* Set global SHM for ust */
3511 if (strlen(wait_shm_path
) == 0) {
3512 snprintf(wait_shm_path
, PATH_MAX
,
3513 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH
);
3516 home_path
= get_home_dir();
3517 if (home_path
== NULL
) {
3518 /* TODO: Add --socket PATH option */
3519 ERR("Can't get HOME directory for sockets creation.");
3524 if (strlen(apps_unix_sock_path
) == 0) {
3525 snprintf(apps_unix_sock_path
, PATH_MAX
,
3526 DEFAULT_HOME_APPS_UNIX_SOCK
, home_path
);
3529 /* Set the cli tool unix socket path */
3530 if (strlen(client_unix_sock_path
) == 0) {
3531 snprintf(client_unix_sock_path
, PATH_MAX
,
3532 DEFAULT_HOME_CLIENT_UNIX_SOCK
, home_path
);
3535 /* Set global SHM for ust */
3536 if (strlen(wait_shm_path
) == 0) {
3537 snprintf(wait_shm_path
, PATH_MAX
,
3538 DEFAULT_HOME_APPS_WAIT_SHM_PATH
, geteuid());
3542 DBG("Client socket path %s", client_unix_sock_path
);
3543 DBG("Application socket path %s", apps_unix_sock_path
);
3546 * See if daemon already exist.
3548 if ((ret
= check_existing_daemon()) < 0) {
3549 ERR("Already running daemon.\n");
3551 * We do not goto exit because we must not cleanup()
3552 * because a daemon is already running.
3557 /* After this point, we can safely call cleanup() with "goto exit" */
3560 * These actions must be executed as root. We do that *after* setting up
3561 * the sockets path because we MUST make the check for another daemon using
3562 * those paths *before* trying to set the kernel consumer sockets and init
3566 ret
= set_kconsumerd_sockets();
3571 /* Setup kernel tracer */
3572 init_kernel_tracer();
3574 /* Set ulimit for open files */
3578 if ((ret
= set_signal_handler()) < 0) {
3582 /* Setup the needed unix socket */
3583 if ((ret
= init_daemon_socket()) < 0) {
3587 /* Set credentials to socket */
3588 if (is_root
&& ((ret
= set_permissions()) < 0)) {
3592 /* Get parent pid if -S, --sig-parent is specified. */
3593 if (opt_sig_parent
) {
3597 /* Setup the kernel pipe for waking up the kernel thread */
3598 if ((ret
= create_kernel_poll_pipe()) < 0) {
3602 /* Setup the thread apps communication pipe. */
3603 if ((ret
= create_apps_cmd_pipe()) < 0) {
3607 /* Init UST command queue. */
3608 cds_wfq_init(&ust_cmd_queue
.queue
);
3611 * Get session list pointer. This pointer MUST NOT be free(). This list is
3612 * statically declared in session.c
3614 session_list_ptr
= session_get_list();
3616 /* Set up max poll set size */
3617 lttng_poll_set_max_size();
3619 /* Create thread to manage the client socket */
3620 ret
= pthread_create(&client_thread
, NULL
,
3621 thread_manage_clients
, (void *) NULL
);
3623 perror("pthread_create clients");
3627 /* Create thread to dispatch registration */
3628 ret
= pthread_create(&dispatch_thread
, NULL
,
3629 thread_dispatch_ust_registration
, (void *) NULL
);
3631 perror("pthread_create dispatch");
3635 /* Create thread to manage application registration. */
3636 ret
= pthread_create(®_apps_thread
, NULL
,
3637 thread_registration_apps
, (void *) NULL
);
3639 perror("pthread_create registration");
3643 /* Create thread to manage application socket */
3644 ret
= pthread_create(&apps_thread
, NULL
,
3645 thread_manage_apps
, (void *) NULL
);
3647 perror("pthread_create apps");
3651 /* Create kernel thread to manage kernel event */
3652 ret
= pthread_create(&kernel_thread
, NULL
,
3653 thread_manage_kernel
, (void *) NULL
);
3655 perror("pthread_create kernel");
3659 tracepoint(sessiond_boot_end
);
3661 ret
= pthread_join(kernel_thread
, &status
);
3663 perror("pthread_join");
3664 goto error
; /* join error, exit without cleanup */
3668 ret
= pthread_join(apps_thread
, &status
);
3670 perror("pthread_join");
3671 goto error
; /* join error, exit without cleanup */
3675 ret
= pthread_join(reg_apps_thread
, &status
);
3677 perror("pthread_join");
3678 goto error
; /* join error, exit without cleanup */
3682 ret
= pthread_join(dispatch_thread
, &status
);
3684 perror("pthread_join");
3685 goto error
; /* join error, exit without cleanup */
3689 ret
= pthread_join(client_thread
, &status
);
3691 perror("pthread_join");
3692 goto error
; /* join error, exit without cleanup */
3695 ret
= join_kconsumerd_thread();
3697 perror("join_kconsumerd");
3698 goto error
; /* join error, exit without cleanup */
3704 * cleanup() is called when no other thread is running.