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 DBG2("Receiving code from kconsumerd_err_sock");
880 /* Getting status code from kconsumerd */
881 ret
= lttcomm_recv_unix_sock(sock
, &code
,
882 sizeof(enum lttcomm_return_code
));
887 if (code
== KCONSUMERD_COMMAND_SOCK_READY
) {
888 kconsumerd_cmd_sock
=
889 lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path
);
890 if (kconsumerd_cmd_sock
< 0) {
891 sem_post(&kconsumerd_sem
);
892 perror("kconsumerd connect");
895 /* Signal condition to tell that the kconsumerd is ready */
896 sem_post(&kconsumerd_sem
);
897 DBG("Kconsumerd command socket ready");
899 ERR("Kconsumerd error when waiting for SOCK_READY : %s",
900 lttcomm_get_readable_code(-code
));
904 /* Remove the kconsumerd error sock since we've established a connexion */
905 ret
= lttng_poll_del(&events
, kconsumerd_err_sock
);
910 ret
= lttng_poll_add(&events
, sock
, LPOLLIN
| LPOLLRDHUP
);
915 /* Update number of fd */
916 nb_fd
= LTTNG_POLL_GETNB(&events
);
918 /* Inifinite blocking call, waiting for transmission */
919 ret
= lttng_poll_wait(&events
, -1);
924 for (i
= 0; i
< nb_fd
; i
++) {
925 /* Fetch once the poll data */
926 revents
= LTTNG_POLL_GETEV(&events
, i
);
927 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
929 /* Thread quit pipe has been closed. Killing thread. */
930 ret
= check_thread_quit_pipe(pollfd
, revents
);
935 /* Event on the kconsumerd socket */
936 if (pollfd
== sock
) {
937 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
938 ERR("Kconsumerd err socket second poll error");
944 /* Wait for any kconsumerd error */
945 ret
= lttcomm_recv_unix_sock(sock
, &code
,
946 sizeof(enum lttcomm_return_code
));
948 ERR("Kconsumerd closed the command socket");
952 ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code
));
955 DBG("Kconsumerd thread dying");
956 close(kconsumerd_err_sock
);
957 close(kconsumerd_cmd_sock
);
960 unlink(kconsumerd_err_unix_sock_path
);
961 unlink(kconsumerd_cmd_unix_sock_path
);
964 lttng_poll_clean(&events
);
970 * This thread manage application communication.
972 static void *thread_manage_apps(void *data
)
975 uint32_t revents
, nb_fd
;
976 struct ust_command ust_cmd
;
977 struct lttng_poll_event events
;
979 tracepoint(sessiond_th_apps_start
);
981 DBG("[thread] Manage application started");
983 ret
= create_thread_poll_set(&events
, 2);
988 ret
= lttng_poll_add(&events
, apps_cmd_pipe
[0], LPOLLIN
| LPOLLRDHUP
);
994 /* Zeroed the events structure */
995 lttng_poll_reset(&events
);
997 nb_fd
= LTTNG_POLL_GETNB(&events
);
999 DBG("Apps thread polling on %d fds", nb_fd
);
1001 tracepoint(sessiond_th_apps_poll
);
1003 /* Inifinite blocking call, waiting for transmission */
1004 ret
= lttng_poll_wait(&events
, -1);
1009 for (i
= 0; i
< nb_fd
; i
++) {
1010 /* Fetch once the poll data */
1011 revents
= LTTNG_POLL_GETEV(&events
, i
);
1012 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
1014 /* Thread quit pipe has been closed. Killing thread. */
1015 ret
= check_thread_quit_pipe(pollfd
, revents
);
1020 /* Inspect the apps cmd pipe */
1021 if (pollfd
== apps_cmd_pipe
[0]) {
1022 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1023 ERR("Apps command pipe error");
1025 } else if (revents
& LPOLLIN
) {
1026 tracepoint(ust_register_read_start
);
1028 ret
= read(apps_cmd_pipe
[0], &ust_cmd
, sizeof(ust_cmd
));
1029 if (ret
< 0 || ret
< sizeof(ust_cmd
)) {
1030 perror("read apps cmd pipe");
1033 tracepoint(ust_register_read_stop
);
1035 tracepoint(ust_register_add_start
);
1036 /* Register applicaton to the session daemon */
1037 ret
= ust_app_register(&ust_cmd
.reg_msg
,
1040 /* Only critical ENOMEM error can be returned here */
1043 tracepoint(ust_register_add_stop
);
1045 tracepoint(ust_register_done_start
);
1046 ret
= ustctl_register_done(ust_cmd
.sock
);
1049 * If the registration is not possible, we simply
1050 * unregister the apps and continue
1052 ust_app_unregister(ust_cmd
.sock
);
1055 * We just need here to monitor the close of the UST
1056 * socket and poll set monitor those by default.
1058 ret
= lttng_poll_add(&events
, ust_cmd
.sock
, 0);
1063 DBG("Apps with sock %d added to poll set",
1066 tracepoint(ust_register_done_stop
);
1071 * At this point, we know that a registered application made
1072 * the event at poll_wait.
1074 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1075 /* Removing from the poll set */
1076 ret
= lttng_poll_del(&events
, pollfd
);
1082 ust_app_unregister(pollfd
);
1090 DBG("Application communication apps dying");
1091 close(apps_cmd_pipe
[0]);
1092 close(apps_cmd_pipe
[1]);
1094 lttng_poll_clean(&events
);
1100 * Dispatch request from the registration threads to the application
1101 * communication thread.
1103 static void *thread_dispatch_ust_registration(void *data
)
1106 struct cds_wfq_node
*node
;
1107 struct ust_command
*ust_cmd
= NULL
;
1109 tracepoint(sessiond_th_dispatch_start
);
1111 DBG("[thread] Dispatch UST command started");
1113 while (!dispatch_thread_exit
) {
1114 /* Atomically prepare the queue futex */
1115 futex_nto1_prepare(&ust_cmd_queue
.futex
);
1118 tracepoint(sessiond_th_dispatch_block
);
1120 /* Dequeue command for registration */
1121 node
= cds_wfq_dequeue_blocking(&ust_cmd_queue
.queue
);
1123 DBG("Waked up but nothing in the UST command queue");
1124 /* Continue thread execution */
1128 tracepoint(ust_dispatch_register_start
);
1130 ust_cmd
= caa_container_of(node
, struct ust_command
, node
);
1132 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1133 " gid:%d sock:%d name:%s (version %d.%d)",
1134 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1135 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1136 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1137 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1139 * Inform apps thread of the new application registration. This
1140 * call is blocking so we can be assured that the data will be read
1141 * at some point in time or wait to the end of the world :)
1143 ret
= write(apps_cmd_pipe
[1], ust_cmd
,
1144 sizeof(struct ust_command
));
1146 perror("write apps cmd pipe");
1147 if (errno
== EBADF
) {
1149 * We can't inform the application thread to process
1150 * registration. We will exit or else application
1151 * registration will not occur and tracing will never
1158 } while (node
!= NULL
);
1160 tracepoint(ust_dispatch_register_stop
);
1162 /* Futex wait on queue. Blocking call on futex() */
1163 futex_nto1_wait(&ust_cmd_queue
.futex
);
1167 DBG("Dispatch thread dying");
1172 * This thread manage application registration.
1174 static void *thread_registration_apps(void *data
)
1176 int sock
= 0, i
, ret
, pollfd
;
1177 uint32_t revents
, nb_fd
;
1178 struct lttng_poll_event events
;
1180 * Get allocated in this thread, enqueued to a global queue, dequeued and
1181 * freed in the manage apps thread.
1183 struct ust_command
*ust_cmd
= NULL
;
1185 tracepoint(sessiond_th_reg_start
);
1187 DBG("[thread] Manage application registration started");
1189 ret
= lttcomm_listen_unix_sock(apps_sock
);
1195 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1196 * more will be added to this poll set.
1198 ret
= create_thread_poll_set(&events
, 2);
1203 /* Add the application registration socket */
1204 ret
= lttng_poll_add(&events
, apps_sock
, LPOLLIN
| LPOLLRDHUP
);
1209 /* Notify all applications to register */
1210 ret
= notify_ust_apps(1);
1212 ERR("Failed to notify applications or create the wait shared memory.\n"
1213 "Execution continues but there might be problem for already\n"
1214 "running applications that wishes to register.");
1218 DBG("Accepting application registration");
1220 tracepoint(sessiond_th_reg_poll
);
1222 nb_fd
= LTTNG_POLL_GETNB(&events
);
1224 /* Inifinite blocking call, waiting for transmission */
1225 ret
= lttng_poll_wait(&events
, -1);
1230 for (i
= 0; i
< nb_fd
; i
++) {
1231 /* Fetch once the poll data */
1232 revents
= LTTNG_POLL_GETEV(&events
, i
);
1233 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
1235 /* Thread quit pipe has been closed. Killing thread. */
1236 ret
= check_thread_quit_pipe(pollfd
, revents
);
1241 /* Event on the registration socket */
1242 if (pollfd
== apps_sock
) {
1243 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1244 ERR("Register apps socket poll error");
1246 } else if (revents
& LPOLLIN
) {
1247 /* Registration starts here. Recording cycles */
1248 tracepoint(ust_register_start
);
1250 sock
= lttcomm_accept_unix_sock(apps_sock
);
1255 /* Create UST registration command for enqueuing */
1256 ust_cmd
= malloc(sizeof(struct ust_command
));
1257 if (ust_cmd
== NULL
) {
1258 perror("ust command malloc");
1263 * Using message-based transmissions to ensure we don't
1264 * have to deal with partially received messages.
1266 ret
= lttcomm_recv_unix_sock(sock
, &ust_cmd
->reg_msg
,
1267 sizeof(struct ust_register_msg
));
1268 if (ret
< 0 || ret
< sizeof(struct ust_register_msg
)) {
1270 perror("lttcomm_recv_unix_sock register apps");
1272 ERR("Wrong size received on apps register");
1279 ust_cmd
->sock
= sock
;
1281 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1282 " gid:%d sock:%d name:%s (version %d.%d)",
1283 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1284 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1285 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1286 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1289 * Lock free enqueue the registration request. The red pill
1290 * has been taken! This apps will be part of the *system*.
1292 cds_wfq_enqueue(&ust_cmd_queue
.queue
, &ust_cmd
->node
);
1295 * Wake the registration queue futex. Implicit memory
1296 * barrier with the exchange in cds_wfq_enqueue.
1298 futex_nto1_wake(&ust_cmd_queue
.futex
);
1300 tracepoint(ust_register_stop
);
1307 DBG("UST Registration thread dying");
1309 /* Notify that the registration thread is gone */
1314 unlink(apps_unix_sock_path
);
1316 lttng_poll_clean(&events
);
1322 * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
1323 * exec or it will fails.
1325 static int spawn_kconsumerd_thread(void)
1328 struct timespec timeout
;
1330 timeout
.tv_sec
= DEFAULT_SEM_WAIT_TIMEOUT
;
1331 timeout
.tv_nsec
= 0;
1333 /* Setup semaphore */
1334 ret
= sem_init(&kconsumerd_sem
, 0, 0);
1336 PERROR("sem_init kconsumerd_sem");
1340 ret
= pthread_create(&kconsumerd_thread
, NULL
,
1341 thread_manage_kconsumerd
, (void *) NULL
);
1343 PERROR("pthread_create kconsumerd");
1348 /* Get time for sem_timedwait absolute timeout */
1349 ret
= clock_gettime(CLOCK_REALTIME
, &timeout
);
1351 PERROR("clock_gettime spawn kconsumerd");
1352 /* Infinite wait for the kconsumerd thread to be ready */
1353 ret
= sem_wait(&kconsumerd_sem
);
1355 /* Normal timeout if the gettime was successful */
1356 timeout
.tv_sec
+= DEFAULT_SEM_WAIT_TIMEOUT
;
1357 ret
= sem_timedwait(&kconsumerd_sem
, &timeout
);
1361 if (errno
== ETIMEDOUT
) {
1363 * Call has timed out so we kill the kconsumerd_thread and return
1366 ERR("The kconsumerd thread was never ready. Killing it");
1367 ret
= pthread_cancel(kconsumerd_thread
);
1369 PERROR("pthread_cancel kconsumerd_thread");
1372 PERROR("semaphore wait failed kconsumerd thread");
1377 pthread_mutex_lock(&kconsumerd_pid_mutex
);
1378 if (kconsumerd_pid
== 0) {
1379 ERR("Kconsumerd did not start");
1380 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1383 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1392 * Join kernel consumer thread
1394 static int join_kconsumerd_thread(void)
1399 if (kconsumerd_pid
!= 0) {
1400 ret
= kill(kconsumerd_pid
, SIGTERM
);
1402 ERR("Error killing kconsumerd");
1405 return pthread_join(kconsumerd_thread
, &status
);
1412 * Fork and exec a kernel consumer daemon (kconsumerd).
1414 * Return pid if successful else -1.
1416 static pid_t
spawn_kconsumerd(void)
1420 const char *verbosity
;
1422 DBG("Spawning kconsumerd");
1429 if (opt_verbose
> 1 || opt_verbose_kconsumerd
) {
1430 verbosity
= "--verbose";
1432 verbosity
= "--quiet";
1434 execl(INSTALL_BIN_PATH
"/ltt-kconsumerd",
1435 "ltt-kconsumerd", verbosity
, NULL
);
1437 perror("kernel start consumer exec");
1440 } else if (pid
> 0) {
1444 perror("kernel start consumer fork");
1454 * Spawn the kconsumerd daemon and session daemon thread.
1456 static int start_kconsumerd(void)
1460 pthread_mutex_lock(&kconsumerd_pid_mutex
);
1461 if (kconsumerd_pid
!= 0) {
1462 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1466 ret
= spawn_kconsumerd();
1468 ERR("Spawning kconsumerd failed");
1469 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1473 /* Setting up the global kconsumerd_pid */
1474 kconsumerd_pid
= ret
;
1475 DBG2("Kconsumerd pid %d", kconsumerd_pid
);
1476 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1478 DBG2("Spawning kconsumerd thread");
1479 ret
= spawn_kconsumerd_thread();
1481 ERR("Fatal error spawning kconsumerd thread");
1493 * modprobe_kernel_modules
1495 static int modprobe_kernel_modules(void)
1500 for (i
= 0; i
< ARRAY_SIZE(kernel_modules_list
); i
++) {
1501 ret
= snprintf(modprobe
, sizeof(modprobe
),
1502 "/sbin/modprobe %s%s",
1503 kernel_modules_list
[i
].required
? "" : "--quiet ",
1504 kernel_modules_list
[i
].name
);
1506 perror("snprintf modprobe");
1509 modprobe
[sizeof(modprobe
) - 1] = '\0';
1510 ret
= system(modprobe
);
1512 ERR("Unable to launch modprobe for module %s",
1513 kernel_modules_list
[i
].name
);
1514 } else if (kernel_modules_list
[i
].required
1515 && WEXITSTATUS(ret
) != 0) {
1516 ERR("Unable to load module %s",
1517 kernel_modules_list
[i
].name
);
1519 DBG("Modprobe successfully %s",
1520 kernel_modules_list
[i
].name
);
1531 static int mount_debugfs(char *path
)
1534 char *type
= "debugfs";
1536 ret
= mkdir_recursive(path
, S_IRWXU
| S_IRWXG
, geteuid(), getegid());
1538 PERROR("Cannot create debugfs path");
1542 ret
= mount(type
, path
, type
, 0, NULL
);
1544 PERROR("Cannot mount debugfs");
1548 DBG("Mounted debugfs successfully at %s", path
);
1555 * Setup necessary data for kernel tracer action.
1557 static void init_kernel_tracer(void)
1560 char *proc_mounts
= "/proc/mounts";
1562 char *debugfs_path
= NULL
, *lttng_path
= NULL
;
1565 /* Detect debugfs */
1566 fp
= fopen(proc_mounts
, "r");
1568 ERR("Unable to probe %s", proc_mounts
);
1572 while (fgets(line
, sizeof(line
), fp
) != NULL
) {
1573 if (strstr(line
, "debugfs") != NULL
) {
1574 /* Remove first string */
1576 /* Dup string here so we can reuse line later on */
1577 debugfs_path
= strdup(strtok(NULL
, " "));
1578 DBG("Got debugfs path : %s", debugfs_path
);
1585 /* Mount debugfs if needded */
1586 if (debugfs_path
== NULL
) {
1587 ret
= asprintf(&debugfs_path
, "/mnt/debugfs");
1589 perror("asprintf debugfs path");
1592 ret
= mount_debugfs(debugfs_path
);
1594 perror("Cannot mount debugfs");
1599 /* Modprobe lttng kernel modules */
1600 ret
= modprobe_kernel_modules();
1605 /* Setup lttng kernel path */
1606 ret
= asprintf(<tng_path
, "%s/lttng", debugfs_path
);
1608 perror("asprintf lttng path");
1612 /* Open debugfs lttng */
1613 kernel_tracer_fd
= open(lttng_path
, O_RDWR
);
1614 if (kernel_tracer_fd
< 0) {
1615 DBG("Failed to open %s", lttng_path
);
1621 DBG("Kernel tracer fd %d", kernel_tracer_fd
);
1631 WARN("No kernel tracer available");
1632 kernel_tracer_fd
= 0;
1637 * Init tracing by creating trace directory and sending fds kernel consumer.
1639 static int init_kernel_tracing(struct ltt_kernel_session
*session
)
1643 if (session
->kconsumer_fds_sent
== 0) {
1645 * Assign default kernel consumer socket if no consumer assigned to the
1646 * kernel session. At this point, it's NOT suppose to be 0 but this is
1647 * an extra security check.
1649 if (session
->consumer_fd
== 0) {
1650 session
->consumer_fd
= kconsumerd_cmd_sock
;
1653 ret
= send_kconsumerd_fds(session
);
1655 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1659 session
->kconsumer_fds_sent
= 1;
1667 * Create an UST session and add it to the session ust list.
1669 static int create_ust_session(struct ltt_session
*session
,
1670 struct lttng_domain
*domain
)
1673 struct ltt_ust_session
*lus
= NULL
;
1674 struct ust_app
*app
;
1676 switch (domain
->type
) {
1677 case LTTNG_DOMAIN_UST_PID
:
1678 app
= ust_app_get_by_pid(domain
->attr
.pid
);
1680 ret
= LTTCOMM_APP_NOT_FOUND
;
1685 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
1689 DBG("Creating UST session");
1691 lus
= trace_ust_create_session(session
->path
, domain
->attr
.pid
, domain
);
1693 ret
= LTTCOMM_UST_SESS_FAIL
;
1697 ret
= mkdir_recursive(lus
->path
, S_IRWXU
| S_IRWXG
,
1698 geteuid(), allowed_group());
1700 if (ret
!= -EEXIST
) {
1701 ERR("Trace directory creation error");
1702 ret
= LTTCOMM_UST_SESS_FAIL
;
1707 /* Create session on the UST tracer */
1708 ret
= ustctl_create_session(app
->sock
, lus
);
1710 ret
= LTTCOMM_UST_SESS_FAIL
;
1714 cds_list_add(&lus
->list
, &session
->ust_session_list
.head
);
1715 session
->ust_session_list
.count
++;
1725 * Create a kernel tracer session then create the default channel.
1727 static int create_kernel_session(struct ltt_session
*session
)
1731 DBG("Creating kernel session");
1733 ret
= kernel_create_session(session
, kernel_tracer_fd
);
1735 ret
= LTTCOMM_KERN_SESS_FAIL
;
1739 /* Set kernel consumer socket fd */
1740 if (kconsumerd_cmd_sock
) {
1741 session
->kernel_session
->consumer_fd
= kconsumerd_cmd_sock
;
1744 ret
= mkdir_recursive(session
->kernel_session
->trace_path
,
1745 S_IRWXU
| S_IRWXG
, geteuid(), allowed_group());
1747 if (ret
!= -EEXIST
) {
1748 ERR("Trace directory creation error");
1758 * Using the session list, filled a lttng_session array to send back to the
1759 * client for session listing.
1761 * The session list lock MUST be acquired before calling this function. Use
1762 * session_lock_list() and session_unlock_list().
1764 static void list_lttng_sessions(struct lttng_session
*sessions
)
1767 struct ltt_session
*session
;
1769 DBG("Getting all available session");
1771 * Iterate over session list and append data after the control struct in
1774 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
1775 strncpy(sessions
[i
].path
, session
->path
, PATH_MAX
);
1776 sessions
[i
].path
[PATH_MAX
- 1] = '\0';
1777 strncpy(sessions
[i
].name
, session
->name
, NAME_MAX
);
1778 sessions
[i
].name
[NAME_MAX
- 1] = '\0';
1784 * Fill lttng_channel array of all channels.
1786 static void list_lttng_channels(struct ltt_session
*session
,
1787 struct lttng_channel
*channels
)
1790 struct ltt_kernel_channel
*kchan
;
1792 DBG("Listing channels for session %s", session
->name
);
1794 /* Kernel channels */
1795 if (session
->kernel_session
!= NULL
) {
1796 cds_list_for_each_entry(kchan
,
1797 &session
->kernel_session
->channel_list
.head
, list
) {
1798 /* Copy lttng_channel struct to array */
1799 memcpy(&channels
[i
], kchan
->channel
, sizeof(struct lttng_channel
));
1800 channels
[i
].enabled
= kchan
->enabled
;
1805 /* TODO: Missing UST listing */
1809 * Fill lttng_event array of all events in the channel.
1811 static void list_lttng_events(struct ltt_kernel_channel
*kchan
,
1812 struct lttng_event
*events
)
1815 * TODO: This is ONLY kernel. Need UST support.
1818 struct ltt_kernel_event
*event
;
1820 DBG("Listing events for channel %s", kchan
->channel
->name
);
1822 /* Kernel channels */
1823 cds_list_for_each_entry(event
, &kchan
->events_list
.head
, list
) {
1824 strncpy(events
[i
].name
, event
->event
->name
, LTTNG_SYMBOL_NAME_LEN
);
1825 events
[i
].name
[LTTNG_SYMBOL_NAME_LEN
- 1] = '\0';
1826 events
[i
].enabled
= event
->enabled
;
1827 switch (event
->event
->instrumentation
) {
1828 case LTTNG_KERNEL_TRACEPOINT
:
1829 events
[i
].type
= LTTNG_EVENT_TRACEPOINT
;
1831 case LTTNG_KERNEL_KPROBE
:
1832 case LTTNG_KERNEL_KRETPROBE
:
1833 events
[i
].type
= LTTNG_EVENT_PROBE
;
1834 memcpy(&events
[i
].attr
.probe
, &event
->event
->u
.kprobe
,
1835 sizeof(struct lttng_kernel_kprobe
));
1837 case LTTNG_KERNEL_FUNCTION
:
1838 events
[i
].type
= LTTNG_EVENT_FUNCTION
;
1839 memcpy(&events
[i
].attr
.ftrace
, &event
->event
->u
.ftrace
,
1840 sizeof(struct lttng_kernel_function
));
1842 case LTTNG_KERNEL_NOOP
:
1843 events
[i
].type
= LTTNG_EVENT_NOOP
;
1845 case LTTNG_KERNEL_SYSCALL
:
1846 events
[i
].type
= LTTNG_EVENT_SYSCALL
;
1848 case LTTNG_KERNEL_ALL
:
1857 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1859 static int cmd_disable_channel(struct ltt_session
*session
,
1860 int domain
, char *channel_name
)
1865 case LTTNG_DOMAIN_KERNEL
:
1866 ret
= channel_kernel_disable(session
->kernel_session
,
1868 if (ret
!= LTTCOMM_OK
) {
1872 kernel_wait_quiescent(kernel_tracer_fd
);
1874 case LTTNG_DOMAIN_UST_PID
:
1877 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
1888 * Copy channel from attributes and set it in the application channel list.
1890 static int copy_ust_channel_to_app(struct ltt_ust_session
*usess
,
1891 struct lttng_channel
*attr
, struct ust_app
*app
)
1894 struct ltt_ust_channel
*uchan
, *new_chan
;
1896 uchan
= trace_ust_get_channel_by_name(attr
->name
, usess
);
1897 if (uchan
== NULL
) {
1898 ret
= LTTCOMM_FATAL
;
1902 new_chan
= trace_ust_create_channel(attr
, usess
->path
);
1903 if (new_chan
== NULL
) {
1904 PERROR("malloc ltt_ust_channel");
1905 ret
= LTTCOMM_FATAL
;
1909 ret
= channel_ust_copy(new_chan
, uchan
);
1911 ret
= LTTCOMM_FATAL
;
1915 /* Add channel to the ust app channel list */
1916 cds_list_add(&new_chan
->list
, &app
->channels
.head
);
1917 app
->channels
.count
++;
1924 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1926 static int cmd_enable_channel(struct ltt_session
*session
,
1927 struct lttng_domain
*domain
, struct lttng_channel
*attr
)
1931 switch (domain
->type
) {
1932 case LTTNG_DOMAIN_KERNEL
:
1934 struct ltt_kernel_channel
*kchan
;
1936 kchan
= trace_kernel_get_channel_by_name(attr
->name
,
1937 session
->kernel_session
);
1938 if (kchan
== NULL
) {
1939 ret
= channel_kernel_create(session
->kernel_session
,
1940 attr
, kernel_poll_pipe
[1]);
1942 ret
= channel_kernel_enable(session
->kernel_session
, kchan
);
1945 if (ret
!= LTTCOMM_OK
) {
1949 kernel_wait_quiescent(kernel_tracer_fd
);
1952 case LTTNG_DOMAIN_UST_PID
:
1955 struct ltt_ust_channel
*uchan
;
1956 struct ltt_ust_session
*usess
;
1957 struct ust_app
*app
;
1959 usess
= trace_ust_get_session_by_pid(&session
->ust_session_list
,
1961 if (usess
== NULL
) {
1962 ret
= LTTCOMM_UST_CHAN_NOT_FOUND
;
1966 app
= ust_app_get_by_pid(domain
->attr
.pid
);
1968 ret
= LTTCOMM_APP_NOT_FOUND
;
1973 uchan
= trace_ust_get_channel_by_name(attr
->name
, usess
);
1974 if (uchan
== NULL
) {
1975 ret
= channel_ust_create(usess
, attr
, sock
);
1977 ret
= channel_ust_enable(usess
, uchan
, sock
);
1980 if (ret
!= LTTCOMM_OK
) {
1984 ret
= copy_ust_channel_to_app(usess
, attr
, app
);
1985 if (ret
!= LTTCOMM_OK
) {
1989 DBG("UST channel %s created for app sock %d with pid %d",
1990 attr
->name
, app
->sock
, domain
->attr
.pid
);
1994 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
2005 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2007 static int cmd_disable_event(struct ltt_session
*session
, int domain
,
2008 char *channel_name
, char *event_name
)
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_tracepoint(session
->kernel_session
, kchan
, event_name
);
2023 if (ret
!= LTTCOMM_OK
) {
2027 kernel_wait_quiescent(kernel_tracer_fd
);
2030 /* TODO: Userspace tracing */
2031 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2042 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2044 static int cmd_disable_event_all(struct ltt_session
*session
, int domain
,
2048 struct ltt_kernel_channel
*kchan
;
2051 case LTTNG_DOMAIN_KERNEL
:
2052 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2053 session
->kernel_session
);
2054 if (kchan
== NULL
) {
2055 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
2059 ret
= event_kernel_disable_all(session
->kernel_session
, kchan
);
2060 if (ret
!= LTTCOMM_OK
) {
2064 kernel_wait_quiescent(kernel_tracer_fd
);
2067 /* TODO: Userspace tracing */
2068 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2079 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2081 static int cmd_add_context(struct ltt_session
*session
, int domain
,
2082 char *channel_name
, char *event_name
, struct lttng_event_context
*ctx
)
2087 case LTTNG_DOMAIN_KERNEL
:
2088 /* Add kernel context to kernel tracer */
2089 ret
= context_kernel_add(session
->kernel_session
, ctx
,
2090 event_name
, channel_name
);
2091 if (ret
!= LTTCOMM_OK
) {
2097 /* TODO: Userspace tracing */
2098 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2109 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2111 static int cmd_enable_event(struct ltt_session
*session
, int domain
,
2112 char *channel_name
, struct lttng_event
*event
)
2115 struct ltt_kernel_channel
*kchan
;
2116 struct lttng_channel
*attr
;
2119 case LTTNG_DOMAIN_KERNEL
:
2120 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2121 session
->kernel_session
);
2122 if (kchan
== NULL
) {
2123 attr
= channel_new_default_attr(domain
);
2125 ret
= LTTCOMM_FATAL
;
2128 snprintf(attr
->name
, NAME_MAX
, "%s", channel_name
);
2130 /* This call will notify the kernel thread */
2131 ret
= channel_kernel_create(session
->kernel_session
,
2132 attr
, kernel_poll_pipe
[1]);
2133 if (ret
!= LTTCOMM_OK
) {
2138 /* Get the newly created kernel channel pointer */
2139 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2140 session
->kernel_session
);
2141 if (kchan
== NULL
) {
2142 /* This sould not happen... */
2143 ret
= LTTCOMM_FATAL
;
2147 ret
= event_kernel_enable_tracepoint(session
->kernel_session
, kchan
, event
);
2148 if (ret
!= LTTCOMM_OK
) {
2152 kernel_wait_quiescent(kernel_tracer_fd
);
2155 /* TODO: Userspace tracing */
2156 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2167 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2169 static int cmd_enable_event_all(struct ltt_session
*session
, int domain
,
2170 char *channel_name
, int event_type
)
2173 struct ltt_kernel_channel
*kchan
;
2176 case LTTNG_DOMAIN_KERNEL
:
2177 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2178 session
->kernel_session
);
2179 if (kchan
== NULL
) {
2180 /* This call will notify the kernel thread */
2181 ret
= channel_kernel_create(session
->kernel_session
, NULL
,
2182 kernel_poll_pipe
[1]);
2183 if (ret
!= LTTCOMM_OK
) {
2188 /* Get the newly created kernel channel pointer */
2189 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2190 session
->kernel_session
);
2191 if (kchan
== NULL
) {
2192 /* This sould not happen... */
2193 ret
= LTTCOMM_FATAL
;
2197 switch (event_type
) {
2198 case LTTNG_KERNEL_SYSCALL
:
2199 ret
= event_kernel_enable_all_syscalls(session
->kernel_session
,
2200 kchan
, kernel_tracer_fd
);
2202 case LTTNG_KERNEL_TRACEPOINT
:
2204 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2205 * events already registered to the channel.
2207 ret
= event_kernel_enable_all_tracepoints(session
->kernel_session
,
2208 kchan
, kernel_tracer_fd
);
2210 case LTTNG_KERNEL_ALL
:
2211 /* Enable syscalls and tracepoints */
2212 ret
= event_kernel_enable_all(session
->kernel_session
,
2213 kchan
, kernel_tracer_fd
);
2216 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2219 if (ret
!= LTTCOMM_OK
) {
2223 kernel_wait_quiescent(kernel_tracer_fd
);
2226 /* TODO: Userspace tracing */
2227 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2238 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2240 static ssize_t
cmd_list_tracepoints(int domain
, struct lttng_event
**events
)
2243 ssize_t nb_events
= 0;
2246 case LTTNG_DOMAIN_KERNEL
:
2247 nb_events
= kernel_list_events(kernel_tracer_fd
, events
);
2248 if (nb_events
< 0) {
2249 ret
= LTTCOMM_KERN_LIST_FAIL
;
2254 /* TODO: Userspace listing */
2255 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2262 /* Return negative value to differentiate return code */
2267 * Command LTTNG_START_TRACE processed by the client thread.
2269 static int cmd_start_trace(struct ltt_session
*session
)
2272 struct ltt_kernel_channel
*kchan
;
2273 struct ltt_kernel_session
*ksession
;
2276 ksession
= session
->kernel_session
;
2278 /* Kernel tracing */
2279 if (ksession
!= NULL
) {
2280 /* Open kernel metadata */
2281 if (ksession
->metadata
== NULL
) {
2282 ret
= kernel_open_metadata(ksession
, ksession
->trace_path
);
2284 ret
= LTTCOMM_KERN_META_FAIL
;
2289 /* Open kernel metadata stream */
2290 if (ksession
->metadata_stream_fd
== 0) {
2291 ret
= kernel_open_metadata_stream(ksession
);
2293 ERR("Kernel create metadata stream failed");
2294 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2299 /* For each channel */
2300 cds_list_for_each_entry(kchan
, &ksession
->channel_list
.head
, list
) {
2301 if (kchan
->stream_count
== 0) {
2302 ret
= kernel_open_channel_stream(kchan
);
2304 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2307 /* Update the stream global counter */
2308 ksession
->stream_count_global
+= ret
;
2312 /* Setup kernel consumer socket and send fds to it */
2313 ret
= init_kernel_tracing(ksession
);
2315 ret
= LTTCOMM_KERN_START_FAIL
;
2319 /* This start the kernel tracing */
2320 ret
= kernel_start_session(ksession
);
2322 ret
= LTTCOMM_KERN_START_FAIL
;
2326 /* Quiescent wait after starting trace */
2327 kernel_wait_quiescent(kernel_tracer_fd
);
2330 /* TODO: Start all UST traces */
2339 * Command LTTNG_STOP_TRACE processed by the client thread.
2341 static int cmd_stop_trace(struct ltt_session
*session
)
2344 struct ltt_kernel_channel
*kchan
;
2345 struct ltt_kernel_session
*ksession
;
2348 ksession
= session
->kernel_session
;
2351 if (ksession
!= NULL
) {
2352 DBG("Stop kernel tracing");
2354 /* Flush all buffers before stopping */
2355 ret
= kernel_metadata_flush_buffer(ksession
->metadata_stream_fd
);
2357 ERR("Kernel metadata flush failed");
2360 cds_list_for_each_entry(kchan
, &ksession
->channel_list
.head
, list
) {
2361 ret
= kernel_flush_buffer(kchan
);
2363 ERR("Kernel flush buffer error");
2367 ret
= kernel_stop_session(ksession
);
2369 ret
= LTTCOMM_KERN_STOP_FAIL
;
2373 kernel_wait_quiescent(kernel_tracer_fd
);
2376 /* TODO : User-space tracer */
2385 * Command LTTNG_CREATE_SESSION processed by the client thread.
2387 static int cmd_create_session(char *name
, char *path
)
2391 ret
= session_create(name
, path
);
2392 if (ret
!= LTTCOMM_OK
) {
2403 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2405 static int cmd_destroy_session(struct ltt_session
*session
, char *name
)
2409 /* Clean kernel session teardown */
2410 teardown_kernel_session(session
);
2413 * Must notify the kernel thread here to update it's poll setin order
2414 * to remove the channel(s)' fd just destroyed.
2416 ret
= notify_thread_pipe(kernel_poll_pipe
[1]);
2418 perror("write kernel poll pipe");
2421 ret
= session_destroy(session
);
2427 * Command LTTNG_CALIBRATE processed by the client thread.
2429 static int cmd_calibrate(int domain
, struct lttng_calibrate
*calibrate
)
2434 case LTTNG_DOMAIN_KERNEL
:
2436 struct lttng_kernel_calibrate kcalibrate
;
2438 kcalibrate
.type
= calibrate
->type
;
2439 ret
= kernel_calibrate(kernel_tracer_fd
, &kcalibrate
);
2441 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2447 /* TODO: Userspace tracing */
2448 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2459 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2461 static int cmd_register_consumer(struct ltt_session
*session
, int domain
,
2467 case LTTNG_DOMAIN_KERNEL
:
2468 /* Can't register a consumer if there is already one */
2469 if (session
->kernel_session
->consumer_fd
!= 0) {
2470 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
2474 sock
= lttcomm_connect_unix_sock(sock_path
);
2476 ret
= LTTCOMM_CONNECT_FAIL
;
2480 session
->kernel_session
->consumer_fd
= sock
;
2483 /* TODO: Userspace tracing */
2484 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2495 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2497 static ssize_t
cmd_list_domains(struct ltt_session
*session
,
2498 struct lttng_domain
**domains
)
2503 if (session
->kernel_session
!= NULL
) {
2507 nb_dom
+= session
->ust_session_list
.count
;
2509 *domains
= malloc(nb_dom
* sizeof(struct lttng_domain
));
2510 if (*domains
== NULL
) {
2511 ret
= -LTTCOMM_FATAL
;
2515 (*domains
)[0].type
= LTTNG_DOMAIN_KERNEL
;
2517 /* TODO: User-space tracer domain support */
2526 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2528 static ssize_t
cmd_list_channels(struct ltt_session
*session
,
2529 struct lttng_channel
**channels
)
2532 ssize_t nb_chan
= 0;
2534 if (session
->kernel_session
!= NULL
) {
2535 nb_chan
+= session
->kernel_session
->channel_count
;
2538 *channels
= malloc(nb_chan
* sizeof(struct lttng_channel
));
2539 if (*channels
== NULL
) {
2540 ret
= -LTTCOMM_FATAL
;
2544 list_lttng_channels(session
, *channels
);
2553 * Command LTTNG_LIST_EVENTS processed by the client thread.
2555 static ssize_t
cmd_list_events(struct ltt_session
*session
,
2556 char *channel_name
, struct lttng_event
**events
)
2559 ssize_t nb_event
= 0;
2560 struct ltt_kernel_channel
*kchan
= NULL
;
2562 if (session
->kernel_session
!= NULL
) {
2563 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2564 session
->kernel_session
);
2565 if (kchan
== NULL
) {
2566 ret
= -LTTCOMM_KERN_CHAN_NOT_FOUND
;
2569 nb_event
+= kchan
->event_count
;
2572 *events
= malloc(nb_event
* sizeof(struct lttng_event
));
2573 if (*events
== NULL
) {
2574 ret
= -LTTCOMM_FATAL
;
2578 list_lttng_events(kchan
, *events
);
2580 /* TODO: User-space tracer support */
2589 * Process the command requested by the lttng client within the command
2590 * context structure. This function make sure that the return structure (llm)
2591 * is set and ready for transmission before returning.
2593 * Return any error encountered or 0 for success.
2595 static int process_client_msg(struct command_ctx
*cmd_ctx
)
2597 int ret
= LTTCOMM_OK
;
2598 int need_tracing_session
= 1;
2600 DBG("Processing client command %d", cmd_ctx
->lsm
->cmd_type
);
2603 * Check for command that don't needs to allocate a returned payload. We do
2604 * this here so we don't have to make the call for no payload at each
2607 switch(cmd_ctx
->lsm
->cmd_type
) {
2608 case LTTNG_LIST_SESSIONS
:
2609 case LTTNG_LIST_TRACEPOINTS
:
2610 case LTTNG_LIST_DOMAINS
:
2611 case LTTNG_LIST_CHANNELS
:
2612 case LTTNG_LIST_EVENTS
:
2615 /* Setup lttng message with no payload */
2616 ret
= setup_lttng_msg(cmd_ctx
, 0);
2618 /* This label does not try to unlock the session */
2619 goto init_setup_error
;
2623 /* Commands that DO NOT need a session. */
2624 switch (cmd_ctx
->lsm
->cmd_type
) {
2625 case LTTNG_CALIBRATE
:
2626 case LTTNG_CREATE_SESSION
:
2627 case LTTNG_LIST_SESSIONS
:
2628 case LTTNG_LIST_TRACEPOINTS
:
2629 need_tracing_session
= 0;
2632 DBG("Getting session %s by name", cmd_ctx
->lsm
->session
.name
);
2633 session_lock_list();
2634 cmd_ctx
->session
= session_find_by_name(cmd_ctx
->lsm
->session
.name
);
2635 session_unlock_list();
2636 if (cmd_ctx
->session
== NULL
) {
2637 if (cmd_ctx
->lsm
->session
.name
!= NULL
) {
2638 ret
= LTTCOMM_SESS_NOT_FOUND
;
2640 /* If no session name specified */
2641 ret
= LTTCOMM_SELECT_SESS
;
2645 /* Acquire lock for the session */
2646 session_lock(cmd_ctx
->session
);
2652 * Check domain type for specific "pre-action".
2654 switch (cmd_ctx
->lsm
->domain
.type
) {
2655 case LTTNG_DOMAIN_KERNEL
:
2656 /* Kernel tracer check */
2657 if (kernel_tracer_fd
== 0) {
2658 /* Basically, load kernel tracer modules */
2659 init_kernel_tracer();
2660 if (kernel_tracer_fd
== 0) {
2661 ret
= LTTCOMM_KERN_NA
;
2666 /* Need a session for kernel command */
2667 if (need_tracing_session
) {
2668 if (cmd_ctx
->session
->kernel_session
== NULL
) {
2669 ret
= create_kernel_session(cmd_ctx
->session
);
2671 ret
= LTTCOMM_KERN_SESS_FAIL
;
2676 /* Start the kernel consumer daemon */
2677 pthread_mutex_lock(&kconsumerd_pid_mutex
);
2678 if (kconsumerd_pid
== 0 &&
2679 cmd_ctx
->lsm
->cmd_type
!= LTTNG_REGISTER_CONSUMER
) {
2680 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
2681 ret
= start_kconsumerd();
2683 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
2687 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
2690 case LTTNG_DOMAIN_UST_PID
:
2692 struct ltt_ust_session
*usess
;
2694 if (need_tracing_session
) {
2695 usess
= trace_ust_get_session_by_pid(
2696 &cmd_ctx
->session
->ust_session_list
,
2697 cmd_ctx
->lsm
->domain
.attr
.pid
);
2698 if (usess
== NULL
) {
2699 ret
= create_ust_session(cmd_ctx
->session
,
2700 &cmd_ctx
->lsm
->domain
);
2701 if (ret
!= LTTCOMM_OK
) {
2709 /* TODO Userspace tracer */
2713 /* Process by command type */
2714 switch (cmd_ctx
->lsm
->cmd_type
) {
2715 case LTTNG_ADD_CONTEXT
:
2717 ret
= cmd_add_context(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2718 cmd_ctx
->lsm
->u
.context
.channel_name
,
2719 cmd_ctx
->lsm
->u
.context
.event_name
,
2720 &cmd_ctx
->lsm
->u
.context
.ctx
);
2723 case LTTNG_DISABLE_CHANNEL
:
2725 ret
= cmd_disable_channel(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2726 cmd_ctx
->lsm
->u
.disable
.channel_name
);
2729 case LTTNG_DISABLE_EVENT
:
2731 ret
= cmd_disable_event(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2732 cmd_ctx
->lsm
->u
.disable
.channel_name
,
2733 cmd_ctx
->lsm
->u
.disable
.name
);
2737 case LTTNG_DISABLE_ALL_EVENT
:
2739 DBG("Disabling all kernel event");
2741 ret
= cmd_disable_event_all(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2742 cmd_ctx
->lsm
->u
.disable
.channel_name
);
2745 case LTTNG_ENABLE_CHANNEL
:
2747 ret
= cmd_enable_channel(cmd_ctx
->session
, &cmd_ctx
->lsm
->domain
,
2748 &cmd_ctx
->lsm
->u
.channel
.chan
);
2751 case LTTNG_ENABLE_EVENT
:
2753 ret
= cmd_enable_event(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2754 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2755 &cmd_ctx
->lsm
->u
.enable
.event
);
2758 case LTTNG_ENABLE_ALL_EVENT
:
2760 DBG("Enabling all kernel event");
2762 ret
= cmd_enable_event_all(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2763 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2764 cmd_ctx
->lsm
->u
.enable
.event
.type
);
2767 case LTTNG_LIST_TRACEPOINTS
:
2769 struct lttng_event
*events
;
2772 nb_events
= cmd_list_tracepoints(cmd_ctx
->lsm
->domain
.type
, &events
);
2773 if (nb_events
< 0) {
2779 * Setup lttng message with payload size set to the event list size in
2780 * bytes and then copy list into the llm payload.
2782 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_event
) * nb_events
);
2788 /* Copy event list into message payload */
2789 memcpy(cmd_ctx
->llm
->payload
, events
,
2790 sizeof(struct lttng_event
) * nb_events
);
2797 case LTTNG_START_TRACE
:
2799 ret
= cmd_start_trace(cmd_ctx
->session
);
2802 case LTTNG_STOP_TRACE
:
2804 ret
= cmd_stop_trace(cmd_ctx
->session
);
2807 case LTTNG_CREATE_SESSION
:
2809 tracepoint(create_session_start
);
2810 ret
= cmd_create_session(cmd_ctx
->lsm
->session
.name
,
2811 cmd_ctx
->lsm
->session
.path
);
2812 tracepoint(create_session_end
);
2815 case LTTNG_DESTROY_SESSION
:
2817 tracepoint(destroy_session_start
);
2818 ret
= cmd_destroy_session(cmd_ctx
->session
,
2819 cmd_ctx
->lsm
->session
.name
);
2820 tracepoint(destroy_session_end
);
2823 case LTTNG_LIST_DOMAINS
:
2826 struct lttng_domain
*domains
;
2828 nb_dom
= cmd_list_domains(cmd_ctx
->session
, &domains
);
2834 ret
= setup_lttng_msg(cmd_ctx
, nb_dom
* sizeof(struct lttng_domain
));
2839 /* Copy event list into message payload */
2840 memcpy(cmd_ctx
->llm
->payload
, domains
,
2841 nb_dom
* sizeof(struct lttng_domain
));
2848 case LTTNG_LIST_CHANNELS
:
2851 struct lttng_channel
*channels
;
2853 nb_chan
= cmd_list_channels(cmd_ctx
->session
, &channels
);
2859 ret
= setup_lttng_msg(cmd_ctx
, nb_chan
* sizeof(struct lttng_channel
));
2864 /* Copy event list into message payload */
2865 memcpy(cmd_ctx
->llm
->payload
, channels
,
2866 nb_chan
* sizeof(struct lttng_channel
));
2873 case LTTNG_LIST_EVENTS
:
2876 struct lttng_event
*events
= NULL
;
2878 nb_event
= cmd_list_events(cmd_ctx
->session
,
2879 cmd_ctx
->lsm
->u
.list
.channel_name
, &events
);
2885 ret
= setup_lttng_msg(cmd_ctx
, nb_event
* sizeof(struct lttng_event
));
2890 /* Copy event list into message payload */
2891 memcpy(cmd_ctx
->llm
->payload
, events
,
2892 nb_event
* sizeof(struct lttng_event
));
2899 case LTTNG_LIST_SESSIONS
:
2901 session_lock_list();
2903 if (session_list_ptr
->count
== 0) {
2904 ret
= LTTCOMM_NO_SESSION
;
2905 session_unlock_list();
2909 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_session
) *
2910 session_list_ptr
->count
);
2912 session_unlock_list();
2916 /* Filled the session array */
2917 list_lttng_sessions((struct lttng_session
*)(cmd_ctx
->llm
->payload
));
2919 session_unlock_list();
2924 case LTTNG_CALIBRATE
:
2926 ret
= cmd_calibrate(cmd_ctx
->lsm
->domain
.type
,
2927 &cmd_ctx
->lsm
->u
.calibrate
);
2930 case LTTNG_REGISTER_CONSUMER
:
2932 ret
= cmd_register_consumer(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2933 cmd_ctx
->lsm
->u
.reg
.path
);
2942 if (cmd_ctx
->llm
== NULL
) {
2943 DBG("Missing llm structure. Allocating one.");
2944 if (setup_lttng_msg(cmd_ctx
, 0) < 0) {
2948 /* Set return code */
2949 cmd_ctx
->llm
->ret_code
= ret
;
2951 if (cmd_ctx
->session
) {
2952 session_unlock(cmd_ctx
->session
);
2959 * This thread manage all clients request using the unix client socket for
2962 static void *thread_manage_clients(void *data
)
2964 int sock
= 0, ret
, i
, pollfd
;
2965 uint32_t revents
, nb_fd
;
2966 struct command_ctx
*cmd_ctx
= NULL
;
2967 struct lttng_poll_event events
;
2969 tracepoint(sessiond_th_cli_start
);
2971 DBG("[thread] Manage client started");
2973 ret
= lttcomm_listen_unix_sock(client_sock
);
2979 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2980 * more will be added to this poll set.
2982 ret
= create_thread_poll_set(&events
, 2);
2987 /* Add the application registration socket */
2988 ret
= lttng_poll_add(&events
, client_sock
, LPOLLIN
| LPOLLPRI
);
2994 * Notify parent pid that we are ready to accept command for client side.
2996 if (opt_sig_parent
) {
2997 kill(ppid
, SIGCHLD
);
3001 DBG("Accepting client command ...");
3003 tracepoint(sessiond_th_cli_poll
);
3005 nb_fd
= LTTNG_POLL_GETNB(&events
);
3007 /* Inifinite blocking call, waiting for transmission */
3008 ret
= lttng_poll_wait(&events
, -1);
3013 for (i
= 0; i
< nb_fd
; i
++) {
3014 /* Fetch once the poll data */
3015 revents
= LTTNG_POLL_GETEV(&events
, i
);
3016 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
3018 /* Thread quit pipe has been closed. Killing thread. */
3019 ret
= check_thread_quit_pipe(pollfd
, revents
);
3024 /* Event on the registration socket */
3025 if (pollfd
== client_sock
) {
3026 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
3027 ERR("Client socket poll error");
3033 DBG("Wait for client response");
3035 sock
= lttcomm_accept_unix_sock(client_sock
);
3040 /* Allocate context command to process the client request */
3041 cmd_ctx
= malloc(sizeof(struct command_ctx
));
3042 if (cmd_ctx
== NULL
) {
3043 perror("malloc cmd_ctx");
3047 /* Allocate data buffer for reception */
3048 cmd_ctx
->lsm
= malloc(sizeof(struct lttcomm_session_msg
));
3049 if (cmd_ctx
->lsm
== NULL
) {
3050 perror("malloc cmd_ctx->lsm");
3054 cmd_ctx
->llm
= NULL
;
3055 cmd_ctx
->session
= NULL
;
3058 * Data is received from the lttng client. The struct
3059 * lttcomm_session_msg (lsm) contains the command and data request of
3062 DBG("Receiving data from client ...");
3063 ret
= lttcomm_recv_unix_sock(sock
, cmd_ctx
->lsm
,
3064 sizeof(struct lttcomm_session_msg
));
3066 DBG("Nothing recv() from client... continuing");
3072 // TODO: Validate cmd_ctx including sanity check for
3073 // security purpose.
3076 * This function dispatch the work to the kernel or userspace tracer
3077 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3078 * informations for the client. The command context struct contains
3079 * everything this function may needs.
3081 ret
= process_client_msg(cmd_ctx
);
3084 * TODO: Inform client somehow of the fatal error. At
3085 * this point, ret < 0 means that a malloc failed
3086 * (ENOMEM). Error detected but still accept command.
3088 clean_command_ctx(&cmd_ctx
);
3092 DBG("Sending response (size: %d, retcode: %s)",
3093 cmd_ctx
->lttng_msg_size
,
3094 lttng_get_readable_code(-cmd_ctx
->llm
->ret_code
));
3095 ret
= send_unix_sock(sock
, cmd_ctx
->llm
, cmd_ctx
->lttng_msg_size
);
3097 ERR("Failed to send data back to client");
3100 clean_command_ctx(&cmd_ctx
);
3102 /* End of transmission */
3107 DBG("Client thread dying");
3108 unlink(client_unix_sock_path
);
3112 lttng_poll_clean(&events
);
3113 clean_command_ctx(&cmd_ctx
);
3119 * usage function on stderr
3121 static void usage(void)
3123 fprintf(stderr
, "Usage: %s OPTIONS\n\nOptions:\n", progname
);
3124 fprintf(stderr
, " -h, --help Display this usage.\n");
3125 fprintf(stderr
, " -c, --client-sock PATH Specify path for the client unix socket\n");
3126 fprintf(stderr
, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3127 fprintf(stderr
, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3128 fprintf(stderr
, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3129 fprintf(stderr
, " -d, --daemonize Start as a daemon.\n");
3130 fprintf(stderr
, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3131 fprintf(stderr
, " -V, --version Show version number.\n");
3132 fprintf(stderr
, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3133 fprintf(stderr
, " -q, --quiet No output at all.\n");
3134 fprintf(stderr
, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3135 fprintf(stderr
, " --verbose-kconsumerd Verbose mode for kconsumerd. Activate DBG() macro.\n");
3139 * daemon argument parsing
3141 static int parse_args(int argc
, char **argv
)
3145 static struct option long_options
[] = {
3146 { "client-sock", 1, 0, 'c' },
3147 { "apps-sock", 1, 0, 'a' },
3148 { "kconsumerd-cmd-sock", 1, 0, 0 },
3149 { "kconsumerd-err-sock", 1, 0, 0 },
3150 { "daemonize", 0, 0, 'd' },
3151 { "sig-parent", 0, 0, 'S' },
3152 { "help", 0, 0, 'h' },
3153 { "group", 1, 0, 'g' },
3154 { "version", 0, 0, 'V' },
3155 { "quiet", 0, 0, 'q' },
3156 { "verbose", 0, 0, 'v' },
3157 { "verbose-kconsumerd", 0, 0, 'Z' },
3162 int option_index
= 0;
3163 c
= getopt_long(argc
, argv
, "dhqvVS" "a:c:g:s:E:C:Z",
3164 long_options
, &option_index
);
3171 fprintf(stderr
, "option %s", long_options
[option_index
].name
);
3173 fprintf(stderr
, " with arg %s\n", optarg
);
3177 snprintf(client_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3180 snprintf(apps_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3186 opt_tracing_group
= strdup(optarg
);
3192 fprintf(stdout
, "%s\n", VERSION
);
3198 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3201 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3207 /* Verbose level can increase using multiple -v */
3211 opt_verbose_kconsumerd
+= 1;
3214 /* Unknown option or other error.
3215 * Error is printed by getopt, just return */
3224 * Creates the two needed socket by the daemon.
3225 * apps_sock - The communication socket for all UST apps.
3226 * client_sock - The communication of the cli tool (lttng).
3228 static int init_daemon_socket(void)
3233 old_umask
= umask(0);
3235 /* Create client tool unix socket */
3236 client_sock
= lttcomm_create_unix_sock(client_unix_sock_path
);
3237 if (client_sock
< 0) {
3238 ERR("Create unix sock failed: %s", client_unix_sock_path
);
3243 /* File permission MUST be 660 */
3244 ret
= chmod(client_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3246 ERR("Set file permissions failed: %s", client_unix_sock_path
);
3251 /* Create the application unix socket */
3252 apps_sock
= lttcomm_create_unix_sock(apps_unix_sock_path
);
3253 if (apps_sock
< 0) {
3254 ERR("Create unix sock failed: %s", apps_unix_sock_path
);
3259 /* File permission MUST be 666 */
3260 ret
= chmod(apps_unix_sock_path
,
3261 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
| S_IROTH
| S_IWOTH
);
3263 ERR("Set file permissions failed: %s", apps_unix_sock_path
);
3274 * Check if the global socket is available, and if a daemon is answering at the
3275 * other side. If yes, error is returned.
3277 static int check_existing_daemon(void)
3279 if (access(client_unix_sock_path
, F_OK
) < 0 &&
3280 access(apps_unix_sock_path
, F_OK
) < 0) {
3284 /* Is there anybody out there ? */
3285 if (lttng_session_daemon_alive()) {
3293 * Set the tracing group gid onto the client socket.
3295 * Race window between mkdir and chown is OK because we are going from more
3296 * permissive (root.root) to les permissive (root.tracing).
3298 static int set_permissions(void)
3303 gid
= allowed_group();
3306 WARN("No tracing group detected");
3309 ERR("Missing tracing group. Aborting execution.");
3315 /* Set lttng run dir */
3316 ret
= chown(LTTNG_RUNDIR
, 0, gid
);
3318 ERR("Unable to set group on " LTTNG_RUNDIR
);
3322 /* lttng client socket path */
3323 ret
= chown(client_unix_sock_path
, 0, gid
);
3325 ERR("Unable to set group on %s", client_unix_sock_path
);
3329 /* kconsumerd error socket path */
3330 ret
= chown(kconsumerd_err_unix_sock_path
, 0, gid
);
3332 ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path
);
3336 DBG("All permissions are set");
3343 * Create the pipe used to wake up the kernel thread.
3345 static int create_kernel_poll_pipe(void)
3347 return pipe2(kernel_poll_pipe
, O_CLOEXEC
);
3351 * Create the application command pipe to wake thread_manage_apps.
3353 static int create_apps_cmd_pipe(void)
3355 return pipe2(apps_cmd_pipe
, O_CLOEXEC
);
3359 * Create the lttng run directory needed for all global sockets and pipe.
3361 static int create_lttng_rundir(void)
3365 ret
= mkdir(LTTNG_RUNDIR
, S_IRWXU
| S_IRWXG
);
3367 if (errno
!= EEXIST
) {
3368 ERR("Unable to create " LTTNG_RUNDIR
);
3380 * Setup sockets and directory needed by the kconsumerd communication with the
3383 static int set_kconsumerd_sockets(void)
3387 if (strlen(kconsumerd_err_unix_sock_path
) == 0) {
3388 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
,
3389 KCONSUMERD_ERR_SOCK_PATH
);
3392 if (strlen(kconsumerd_cmd_unix_sock_path
) == 0) {
3393 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
,
3394 KCONSUMERD_CMD_SOCK_PATH
);
3397 ret
= mkdir(KCONSUMERD_PATH
, S_IRWXU
| S_IRWXG
);
3399 if (errno
!= EEXIST
) {
3400 ERR("Failed to create " KCONSUMERD_PATH
);
3406 /* Create the kconsumerd error unix socket */
3407 kconsumerd_err_sock
=
3408 lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path
);
3409 if (kconsumerd_err_sock
< 0) {
3410 ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path
);
3415 /* File permission MUST be 660 */
3416 ret
= chmod(kconsumerd_err_unix_sock_path
,
3417 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3419 ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path
);
3429 * Signal handler for the daemon
3431 * Simply stop all worker threads, leaving main() return gracefully after
3432 * joining all threads and calling cleanup().
3434 static void sighandler(int sig
)
3438 DBG("SIGPIPE catched");
3441 DBG("SIGINT catched");
3445 DBG("SIGTERM catched");
3454 * Setup signal handler for :
3455 * SIGINT, SIGTERM, SIGPIPE
3457 static int set_signal_handler(void)
3460 struct sigaction sa
;
3463 if ((ret
= sigemptyset(&sigset
)) < 0) {
3464 perror("sigemptyset");
3468 sa
.sa_handler
= sighandler
;
3469 sa
.sa_mask
= sigset
;
3471 if ((ret
= sigaction(SIGTERM
, &sa
, NULL
)) < 0) {
3472 perror("sigaction");
3476 if ((ret
= sigaction(SIGINT
, &sa
, NULL
)) < 0) {
3477 perror("sigaction");
3481 if ((ret
= sigaction(SIGPIPE
, &sa
, NULL
)) < 0) {
3482 perror("sigaction");
3486 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3492 * Set open files limit to unlimited. This daemon can open a large number of
3493 * file descriptors in order to consumer multiple kernel traces.
3495 static void set_ulimit(void)
3500 /* The kernel does not allowed an infinite limit for open files */
3501 lim
.rlim_cur
= 65535;
3502 lim
.rlim_max
= 65535;
3504 ret
= setrlimit(RLIMIT_NOFILE
, &lim
);
3506 perror("failed to set open files limit");
3513 int main(int argc
, char **argv
)
3517 const char *home_path
;
3519 tracepoint(sessiond_boot_start
);
3521 /* Create thread quit pipe */
3522 if ((ret
= init_thread_quit_pipe()) < 0) {
3526 /* Parse arguments */
3528 if ((ret
= parse_args(argc
, argv
) < 0)) {
3541 /* Check if daemon is UID = 0 */
3542 is_root
= !getuid();
3545 ret
= create_lttng_rundir();
3550 if (strlen(apps_unix_sock_path
) == 0) {
3551 snprintf(apps_unix_sock_path
, PATH_MAX
,
3552 DEFAULT_GLOBAL_APPS_UNIX_SOCK
);
3555 if (strlen(client_unix_sock_path
) == 0) {
3556 snprintf(client_unix_sock_path
, PATH_MAX
,
3557 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
);
3560 /* Set global SHM for ust */
3561 if (strlen(wait_shm_path
) == 0) {
3562 snprintf(wait_shm_path
, PATH_MAX
,
3563 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH
);
3566 home_path
= get_home_dir();
3567 if (home_path
== NULL
) {
3568 /* TODO: Add --socket PATH option */
3569 ERR("Can't get HOME directory for sockets creation.");
3574 if (strlen(apps_unix_sock_path
) == 0) {
3575 snprintf(apps_unix_sock_path
, PATH_MAX
,
3576 DEFAULT_HOME_APPS_UNIX_SOCK
, home_path
);
3579 /* Set the cli tool unix socket path */
3580 if (strlen(client_unix_sock_path
) == 0) {
3581 snprintf(client_unix_sock_path
, PATH_MAX
,
3582 DEFAULT_HOME_CLIENT_UNIX_SOCK
, home_path
);
3585 /* Set global SHM for ust */
3586 if (strlen(wait_shm_path
) == 0) {
3587 snprintf(wait_shm_path
, PATH_MAX
,
3588 DEFAULT_HOME_APPS_WAIT_SHM_PATH
, geteuid());
3592 DBG("Client socket path %s", client_unix_sock_path
);
3593 DBG("Application socket path %s", apps_unix_sock_path
);
3596 * See if daemon already exist.
3598 if ((ret
= check_existing_daemon()) < 0) {
3599 ERR("Already running daemon.\n");
3601 * We do not goto exit because we must not cleanup()
3602 * because a daemon is already running.
3607 /* After this point, we can safely call cleanup() with "goto exit" */
3610 * These actions must be executed as root. We do that *after* setting up
3611 * the sockets path because we MUST make the check for another daemon using
3612 * those paths *before* trying to set the kernel consumer sockets and init
3616 ret
= set_kconsumerd_sockets();
3621 /* Setup kernel tracer */
3622 init_kernel_tracer();
3624 /* Set ulimit for open files */
3628 if ((ret
= set_signal_handler()) < 0) {
3632 /* Setup the needed unix socket */
3633 if ((ret
= init_daemon_socket()) < 0) {
3637 /* Set credentials to socket */
3638 if (is_root
&& ((ret
= set_permissions()) < 0)) {
3642 /* Get parent pid if -S, --sig-parent is specified. */
3643 if (opt_sig_parent
) {
3647 /* Setup the kernel pipe for waking up the kernel thread */
3648 if ((ret
= create_kernel_poll_pipe()) < 0) {
3652 /* Setup the thread apps communication pipe. */
3653 if ((ret
= create_apps_cmd_pipe()) < 0) {
3657 /* Init UST command queue. */
3658 cds_wfq_init(&ust_cmd_queue
.queue
);
3661 * Get session list pointer. This pointer MUST NOT be free(). This list is
3662 * statically declared in session.c
3664 session_list_ptr
= session_get_list();
3666 /* Set up max poll set size */
3667 lttng_poll_set_max_size();
3669 /* Create thread to manage the client socket */
3670 ret
= pthread_create(&client_thread
, NULL
,
3671 thread_manage_clients
, (void *) NULL
);
3673 perror("pthread_create clients");
3677 /* Create thread to dispatch registration */
3678 ret
= pthread_create(&dispatch_thread
, NULL
,
3679 thread_dispatch_ust_registration
, (void *) NULL
);
3681 perror("pthread_create dispatch");
3685 /* Create thread to manage application registration. */
3686 ret
= pthread_create(®_apps_thread
, NULL
,
3687 thread_registration_apps
, (void *) NULL
);
3689 perror("pthread_create registration");
3693 /* Create thread to manage application socket */
3694 ret
= pthread_create(&apps_thread
, NULL
,
3695 thread_manage_apps
, (void *) NULL
);
3697 perror("pthread_create apps");
3701 /* Create kernel thread to manage kernel event */
3702 ret
= pthread_create(&kernel_thread
, NULL
,
3703 thread_manage_kernel
, (void *) NULL
);
3705 perror("pthread_create kernel");
3709 tracepoint(sessiond_boot_end
);
3711 ret
= pthread_join(kernel_thread
, &status
);
3713 perror("pthread_join");
3714 goto error
; /* join error, exit without cleanup */
3718 ret
= pthread_join(apps_thread
, &status
);
3720 perror("pthread_join");
3721 goto error
; /* join error, exit without cleanup */
3725 ret
= pthread_join(reg_apps_thread
, &status
);
3727 perror("pthread_join");
3728 goto error
; /* join error, exit without cleanup */
3732 ret
= pthread_join(dispatch_thread
, &status
);
3734 perror("pthread_join");
3735 goto error
; /* join error, exit without cleanup */
3739 ret
= pthread_join(client_thread
, &status
);
3741 perror("pthread_join");
3742 goto error
; /* join error, exit without cleanup */
3745 ret
= join_kconsumerd_thread();
3747 perror("join_kconsumerd");
3748 goto error
; /* join error, exit without cleanup */
3754 * cleanup() is called when no other thread is running.