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"
59 const char default_home_dir
[] = DEFAULT_HOME_DIR
;
60 const char default_tracing_group
[] = LTTNG_DEFAULT_TRACING_GROUP
;
61 const char default_ust_sock_dir
[] = DEFAULT_UST_SOCK_DIR
;
62 const char default_global_apps_pipe
[] = DEFAULT_GLOBAL_APPS_PIPE
;
65 int opt_verbose
; /* Not static for lttngerr.h */
66 int opt_verbose_kconsumerd
; /* Not static for lttngerr.h */
67 int opt_quiet
; /* Not static for lttngerr.h */
70 const char *opt_tracing_group
;
71 static int opt_sig_parent
;
72 static int opt_daemon
;
73 static int is_root
; /* Set to 1 if the daemon is running as root */
74 static pid_t ppid
; /* Parent PID for --sig-parent option */
75 static pid_t kconsumerd_pid
;
76 static int dispatch_thread_exit
;
78 /* Global application Unix socket path */
79 static char apps_unix_sock_path
[PATH_MAX
];
80 /* Global client Unix socket path */
81 static char client_unix_sock_path
[PATH_MAX
];
82 /* kconsumerd error and command Unix socket path */
83 static char kconsumerd_err_unix_sock_path
[PATH_MAX
];
84 static char kconsumerd_cmd_unix_sock_path
[PATH_MAX
];
85 /* global wait shm path for UST */
86 static char wait_shm_path
[PATH_MAX
];
89 static int client_sock
;
91 static int kconsumerd_err_sock
;
92 static int kconsumerd_cmd_sock
;
93 static int kernel_tracer_fd
;
94 static int kernel_poll_pipe
[2];
97 * Quit pipe for all threads. This permits a single cancellation point
98 * for all threads when receiving an event on the pipe.
100 static int thread_quit_pipe
[2];
103 * This pipe is used to inform the thread managing application communication
104 * that a command is queued and ready to be processed.
106 static int apps_cmd_pipe
[2];
108 /* Pthread, Mutexes and Semaphores */
109 static pthread_t kconsumerd_thread
;
110 static pthread_t apps_thread
;
111 static pthread_t reg_apps_thread
;
112 static pthread_t client_thread
;
113 static pthread_t kernel_thread
;
114 static pthread_t dispatch_thread
;
115 static sem_t kconsumerd_sem
;
118 /* Mutex to control kconsumerd pid assignation */
119 static pthread_mutex_t kconsumerd_pid_mutex
;
122 * UST registration command queue. This queue is tied with a futex and uses a N
123 * wakers / 1 waiter implemented and detailed in futex.c/.h
125 * The thread_manage_apps and thread_dispatch_ust_registration interact with
126 * this queue and the wait/wake scheme.
128 static struct ust_cmd_queue ust_cmd_queue
;
131 * Pointer initialized before thread creation.
133 * This points to the tracing session list containing the session count and a
134 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
135 * MUST NOT be taken if you call a public function in session.c.
137 * The lock is nested inside the structure: session_list_ptr->lock. Please use
138 * session_lock_list and session_unlock_list for lock acquisition.
140 static struct ltt_session_list
*session_list_ptr
;
143 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
145 static int create_thread_poll_set(struct lttng_poll_event
*events
,
150 if (events
== NULL
|| size
== 0) {
155 ret
= lttng_poll_create(events
, size
, LTTNG_CLOEXEC
);
161 ret
= lttng_poll_add(events
, thread_quit_pipe
[0], LPOLLIN
);
173 * Check if the thread quit pipe was triggered.
175 * Return 1 if it was triggered else 0;
177 static int check_thread_quit_pipe(int fd
, uint32_t events
)
179 if (fd
== thread_quit_pipe
[0] && (events
& LPOLLIN
)) {
187 * Remove modules in reverse load order.
189 static int modprobe_remove_kernel_modules(void)
194 for (i
= ARRAY_SIZE(kernel_modules_list
) - 1; i
>= 0; i
--) {
195 ret
= snprintf(modprobe
, sizeof(modprobe
),
196 "/sbin/modprobe --remove --quiet %s",
197 kernel_modules_list
[i
].name
);
199 perror("snprintf modprobe --remove");
202 modprobe
[sizeof(modprobe
) - 1] = '\0';
203 ret
= system(modprobe
);
205 ERR("Unable to launch modprobe --remove for module %s",
206 kernel_modules_list
[i
].name
);
207 } else if (kernel_modules_list
[i
].required
208 && WEXITSTATUS(ret
) != 0) {
209 ERR("Unable to remove module %s",
210 kernel_modules_list
[i
].name
);
212 DBG("Modprobe removal successful %s",
213 kernel_modules_list
[i
].name
);
222 * Return group ID of the tracing group or -1 if not found.
224 static gid_t
allowed_group(void)
228 if (opt_tracing_group
) {
229 grp
= getgrnam(opt_tracing_group
);
231 grp
= getgrnam(default_tracing_group
);
241 * Init thread quit pipe.
243 * Return -1 on error or 0 if all pipes are created.
245 static int init_thread_quit_pipe(void)
249 ret
= pipe2(thread_quit_pipe
, O_CLOEXEC
);
251 perror("thread quit pipe");
260 * Complete teardown of a kernel session. This free all data structure related
261 * to a kernel session and update counter.
263 static void teardown_kernel_session(struct ltt_session
*session
)
265 if (session
->kernel_session
!= NULL
) {
266 DBG("Tearing down kernel session");
269 * If a custom kernel consumer was registered, close the socket before
270 * tearing down the complete kernel session structure
272 if (session
->kernel_session
->consumer_fd
!= kconsumerd_cmd_sock
) {
273 lttcomm_close_unix_sock(session
->kernel_session
->consumer_fd
);
276 trace_kernel_destroy_session(session
->kernel_session
);
277 /* Extra precaution */
278 session
->kernel_session
= NULL
;
283 * Stop all threads by closing the thread quit pipe.
285 static void stop_threads(void)
289 /* Stopping all threads */
290 DBG("Terminating all threads");
291 ret
= notify_thread_pipe(thread_quit_pipe
[1]);
293 ERR("write error on thread quit pipe");
296 /* Dispatch thread */
297 dispatch_thread_exit
= 1;
298 futex_nto1_wake(&ust_cmd_queue
.futex
);
304 static void cleanup(void)
308 struct ltt_session
*sess
, *stmp
;
313 MSG("%c[%d;%dm*** assert failed *** ==> %c[%dm%c[%d;%dm"
314 "Matthew, BEET driven development works!%c[%dm",
315 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
319 DBG("Removing %s directory", LTTNG_RUNDIR
);
320 ret
= asprintf(&cmd
, "rm -rf " LTTNG_RUNDIR
);
322 ERR("asprintf failed. Something is really wrong!");
325 /* Remove lttng run directory */
328 ERR("Unable to clean " LTTNG_RUNDIR
);
332 DBG("Cleaning up all session");
334 /* Destroy session list mutex */
335 if (session_list_ptr
!= NULL
) {
336 pthread_mutex_destroy(&session_list_ptr
->lock
);
338 /* Cleanup ALL session */
339 cds_list_for_each_entry_safe(sess
, stmp
,
340 &session_list_ptr
->head
, list
) {
341 teardown_kernel_session(sess
);
342 // TODO complete session cleanup (including UST)
346 DBG("Closing all UST sockets");
347 ust_app_clean_list();
349 pthread_mutex_destroy(&kconsumerd_pid_mutex
);
351 DBG("Closing kernel fd");
352 close(kernel_tracer_fd
);
355 DBG("Unloading kernel modules");
356 modprobe_remove_kernel_modules();
359 close(thread_quit_pipe
[0]);
360 close(thread_quit_pipe
[1]);
364 * Send data on a unix socket using the liblttsessiondcomm API.
366 * Return lttcomm error code.
368 static int send_unix_sock(int sock
, void *buf
, size_t len
)
370 /* Check valid length */
375 return lttcomm_send_unix_sock(sock
, buf
, len
);
379 * Free memory of a command context structure.
381 static void clean_command_ctx(struct command_ctx
**cmd_ctx
)
383 DBG("Clean command context structure");
385 if ((*cmd_ctx
)->llm
) {
386 free((*cmd_ctx
)->llm
);
388 if ((*cmd_ctx
)->lsm
) {
389 free((*cmd_ctx
)->lsm
);
397 * Send all stream fds of kernel channel to the consumer.
399 static int send_kconsumerd_channel_fds(int sock
,
400 struct ltt_kernel_channel
*channel
)
404 struct ltt_kernel_stream
*stream
;
405 struct lttcomm_kconsumerd_header lkh
;
406 struct lttcomm_kconsumerd_msg lkm
;
408 DBG("Sending fds of channel %s to kernel consumer",
409 channel
->channel
->name
);
411 nb_fd
= channel
->stream_count
;
414 lkh
.payload_size
= nb_fd
* sizeof(struct lttcomm_kconsumerd_msg
);
415 lkh
.cmd_type
= ADD_STREAM
;
417 DBG("Sending kconsumerd header");
419 ret
= lttcomm_send_unix_sock(sock
, &lkh
,
420 sizeof(struct lttcomm_kconsumerd_header
));
422 perror("send kconsumerd header");
426 cds_list_for_each_entry(stream
, &channel
->stream_list
.head
, list
) {
427 if (stream
->fd
!= 0) {
429 lkm
.state
= stream
->state
;
430 lkm
.max_sb_size
= channel
->channel
->attr
.subbuf_size
;
431 lkm
.output
= channel
->channel
->attr
.output
;
432 strncpy(lkm
.path_name
, stream
->pathname
, PATH_MAX
);
433 lkm
.path_name
[PATH_MAX
- 1] = '\0';
435 DBG("Sending fd %d to kconsumerd", lkm
.fd
);
437 ret
= lttcomm_send_fds_unix_sock(sock
, &lkm
,
438 &lkm
.fd
, 1, sizeof(lkm
));
440 perror("send kconsumerd fd");
446 DBG("Kconsumerd channel fds sent");
455 * Send all stream fds of the kernel session to the consumer.
457 static int send_kconsumerd_fds(struct ltt_kernel_session
*session
)
460 struct ltt_kernel_channel
*chan
;
461 struct lttcomm_kconsumerd_header lkh
;
462 struct lttcomm_kconsumerd_msg lkm
;
465 lkh
.payload_size
= sizeof(struct lttcomm_kconsumerd_msg
);
466 lkh
.cmd_type
= ADD_STREAM
;
468 DBG("Sending kconsumerd header for metadata");
470 ret
= lttcomm_send_unix_sock(session
->consumer_fd
, &lkh
,
471 sizeof(struct lttcomm_kconsumerd_header
));
473 perror("send kconsumerd header");
477 DBG("Sending metadata stream fd");
479 /* Extra protection. It's NOT suppose to be set to 0 at this point */
480 if (session
->consumer_fd
== 0) {
481 session
->consumer_fd
= kconsumerd_cmd_sock
;
484 if (session
->metadata_stream_fd
!= 0) {
485 /* Send metadata stream fd first */
486 lkm
.fd
= session
->metadata_stream_fd
;
487 lkm
.state
= ACTIVE_FD
;
488 lkm
.max_sb_size
= session
->metadata
->conf
->attr
.subbuf_size
;
489 lkm
.output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
490 strncpy(lkm
.path_name
, session
->metadata
->pathname
, PATH_MAX
);
491 lkm
.path_name
[PATH_MAX
- 1] = '\0';
493 ret
= lttcomm_send_fds_unix_sock(session
->consumer_fd
, &lkm
,
494 &lkm
.fd
, 1, sizeof(lkm
));
496 perror("send kconsumerd fd");
501 cds_list_for_each_entry(chan
, &session
->channel_list
.head
, list
) {
502 ret
= send_kconsumerd_channel_fds(session
->consumer_fd
, chan
);
508 DBG("Kconsumerd fds (metadata and channel streams) sent");
517 * Notify UST applications using the shm mmap futex.
519 static int notify_ust_apps(int active
)
523 DBG("Notifying applications of session daemon state: %d", active
);
525 /* See shm.c for this call implying mmap, shm and futex calls */
526 wait_shm_mmap
= shm_ust_get_mmap(wait_shm_path
, is_root
);
527 if (wait_shm_mmap
== NULL
) {
531 /* Wake waiting process */
532 futex_wait_update((int32_t *) wait_shm_mmap
, active
);
534 /* Apps notified successfully */
542 * Setup the outgoing data buffer for the response (llm) by allocating the
543 * right amount of memory and copying the original information from the lsm
546 * Return total size of the buffer pointed by buf.
548 static int setup_lttng_msg(struct command_ctx
*cmd_ctx
, size_t size
)
554 cmd_ctx
->llm
= malloc(sizeof(struct lttcomm_lttng_msg
) + buf_size
);
555 if (cmd_ctx
->llm
== NULL
) {
561 /* Copy common data */
562 cmd_ctx
->llm
->cmd_type
= cmd_ctx
->lsm
->cmd_type
;
563 cmd_ctx
->llm
->pid
= cmd_ctx
->lsm
->domain
.attr
.pid
;
565 cmd_ctx
->llm
->data_size
= size
;
566 cmd_ctx
->lttng_msg_size
= sizeof(struct lttcomm_lttng_msg
) + buf_size
;
575 * Update the kernel poll set of all channel fd available over all tracing
576 * session. Add the wakeup pipe at the end of the set.
578 static int update_kernel_poll(struct lttng_poll_event
*events
)
581 struct ltt_session
*session
;
582 struct ltt_kernel_channel
*channel
;
584 DBG("Updating kernel poll set");
587 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
588 session_lock(session
);
589 if (session
->kernel_session
== NULL
) {
590 session_unlock(session
);
594 cds_list_for_each_entry(channel
,
595 &session
->kernel_session
->channel_list
.head
, list
) {
596 /* Add channel fd to the kernel poll set */
597 ret
= lttng_poll_add(events
, channel
->fd
, LPOLLIN
| LPOLLRDNORM
);
599 session_unlock(session
);
602 DBG("Channel fd %d added to kernel set", channel
->fd
);
604 session_unlock(session
);
606 session_unlock_list();
611 session_unlock_list();
616 * Find the channel fd from 'fd' over all tracing session. When found, check
617 * for new channel stream and send those stream fds to the kernel consumer.
619 * Useful for CPU hotplug feature.
621 static int update_kernel_stream(int fd
)
624 struct ltt_session
*session
;
625 struct ltt_kernel_channel
*channel
;
627 DBG("Updating kernel streams for channel fd %d", fd
);
630 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
631 session_lock(session
);
632 if (session
->kernel_session
== NULL
) {
633 session_unlock(session
);
637 /* This is not suppose to be 0 but this is an extra security check */
638 if (session
->kernel_session
->consumer_fd
== 0) {
639 session
->kernel_session
->consumer_fd
= kconsumerd_cmd_sock
;
642 cds_list_for_each_entry(channel
,
643 &session
->kernel_session
->channel_list
.head
, list
) {
644 if (channel
->fd
== fd
) {
645 DBG("Channel found, updating kernel streams");
646 ret
= kernel_open_channel_stream(channel
);
652 * Have we already sent fds to the consumer? If yes, it means
653 * that tracing is started so it is safe to send our updated
656 if (session
->kernel_session
->kconsumer_fds_sent
== 1) {
657 ret
= send_kconsumerd_channel_fds(
658 session
->kernel_session
->consumer_fd
, channel
);
666 session_unlock(session
);
668 session_unlock_list();
672 session_unlock(session
);
673 session_unlock_list();
678 * This thread manage event coming from the kernel.
680 * Features supported in this thread:
683 static void *thread_manage_kernel(void *data
)
685 int ret
, i
, pollfd
, update_poll_flag
= 1;
686 uint32_t revents
, nb_fd
;
688 struct lttng_poll_event events
;
690 DBG("Thread manage kernel started");
692 ret
= create_thread_poll_set(&events
, 2);
697 ret
= lttng_poll_add(&events
, kernel_poll_pipe
[0], LPOLLIN
);
703 if (update_poll_flag
== 1) {
705 * Reset number of fd in the poll set. Always 2 since there is the thread
706 * quit pipe and the kernel pipe.
710 ret
= update_kernel_poll(&events
);
714 update_poll_flag
= 0;
717 nb_fd
= LTTNG_POLL_GETNB(&events
);
719 DBG("Thread kernel polling on %d fds", nb_fd
);
721 /* Zeroed the poll events */
722 lttng_poll_reset(&events
);
724 /* Poll infinite value of time */
725 ret
= lttng_poll_wait(&events
, -1);
728 } else if (ret
== 0) {
729 /* Should not happen since timeout is infinite */
730 ERR("Return value of poll is 0 with an infinite timeout.\n"
731 "This should not have happened! Continuing...");
735 for (i
= 0; i
< nb_fd
; i
++) {
736 /* Fetch once the poll data */
737 revents
= LTTNG_POLL_GETEV(&events
, i
);
738 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
740 /* Thread quit pipe has been closed. Killing thread. */
741 ret
= check_thread_quit_pipe(pollfd
, revents
);
746 /* Check for data on kernel pipe */
747 if (pollfd
== kernel_poll_pipe
[0] && (revents
& LPOLLIN
)) {
748 ret
= read(kernel_poll_pipe
[0], &tmp
, 1);
749 update_poll_flag
= 1;
753 * New CPU detected by the kernel. Adding kernel stream to
754 * kernel session and updating the kernel consumer
756 if (revents
& LPOLLIN
) {
757 ret
= update_kernel_stream(pollfd
);
763 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
764 * and unregister kernel stream at this point.
772 DBG("Kernel thread dying");
773 close(kernel_poll_pipe
[0]);
774 close(kernel_poll_pipe
[1]);
776 lttng_poll_clean(&events
);
782 * This thread manage the kconsumerd error sent back to the session daemon.
784 static void *thread_manage_kconsumerd(void *data
)
786 int sock
= 0, i
, ret
, pollfd
;
787 uint32_t revents
, nb_fd
;
788 enum lttcomm_return_code code
;
789 struct lttng_poll_event events
;
791 DBG("[thread] Manage kconsumerd started");
793 ret
= lttcomm_listen_unix_sock(kconsumerd_err_sock
);
799 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
800 * Nothing more will be added to this poll set.
802 ret
= create_thread_poll_set(&events
, 2);
807 ret
= lttng_poll_add(&events
, kconsumerd_err_sock
, LPOLLIN
| LPOLLRDHUP
);
812 nb_fd
= LTTNG_POLL_GETNB(&events
);
814 /* Inifinite blocking call, waiting for transmission */
815 ret
= lttng_poll_wait(&events
, -1);
820 for (i
= 0; i
< nb_fd
; i
++) {
821 /* Fetch once the poll data */
822 revents
= LTTNG_POLL_GETEV(&events
, i
);
823 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
825 /* Thread quit pipe has been closed. Killing thread. */
826 ret
= check_thread_quit_pipe(pollfd
, revents
);
831 /* Event on the registration socket */
832 if (pollfd
== kconsumerd_err_sock
) {
833 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
834 ERR("Kconsumerd err socket poll error");
840 sock
= lttcomm_accept_unix_sock(kconsumerd_err_sock
);
845 /* Getting status code from kconsumerd */
846 ret
= lttcomm_recv_unix_sock(sock
, &code
,
847 sizeof(enum lttcomm_return_code
));
852 if (code
== KCONSUMERD_COMMAND_SOCK_READY
) {
853 kconsumerd_cmd_sock
=
854 lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path
);
855 if (kconsumerd_cmd_sock
< 0) {
856 sem_post(&kconsumerd_sem
);
857 perror("kconsumerd connect");
860 /* Signal condition to tell that the kconsumerd is ready */
861 sem_post(&kconsumerd_sem
);
862 DBG("Kconsumerd command socket ready");
864 DBG("Kconsumerd error when waiting for SOCK_READY : %s",
865 lttcomm_get_readable_code(-code
));
869 /* Remove the kconsumerd error sock since we've established a connexion */
870 ret
= lttng_poll_del(&events
, kconsumerd_err_sock
);
875 ret
= lttng_poll_add(&events
, sock
, LPOLLIN
| LPOLLRDHUP
);
880 /* Update number of fd */
881 nb_fd
= LTTNG_POLL_GETNB(&events
);
883 /* Inifinite blocking call, waiting for transmission */
884 ret
= lttng_poll_wait(&events
, -1);
889 for (i
= 0; i
< nb_fd
; i
++) {
890 /* Fetch once the poll data */
891 revents
= LTTNG_POLL_GETEV(&events
, i
);
892 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
894 /* Thread quit pipe has been closed. Killing thread. */
895 ret
= check_thread_quit_pipe(pollfd
, revents
);
900 /* Event on the kconsumerd socket */
901 if (pollfd
== sock
) {
902 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
903 ERR("Kconsumerd err socket second poll error");
909 /* Wait for any kconsumerd error */
910 ret
= lttcomm_recv_unix_sock(sock
, &code
,
911 sizeof(enum lttcomm_return_code
));
913 ERR("Kconsumerd closed the command socket");
917 ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code
));
920 DBG("Kconsumerd thread dying");
921 close(kconsumerd_err_sock
);
922 close(kconsumerd_cmd_sock
);
925 unlink(kconsumerd_err_unix_sock_path
);
926 unlink(kconsumerd_cmd_unix_sock_path
);
929 lttng_poll_clean(&events
);
935 * This thread manage application communication.
937 static void *thread_manage_apps(void *data
)
940 uint32_t revents
, nb_fd
;
941 struct ust_command ust_cmd
;
942 struct lttng_poll_event events
;
944 DBG("[thread] Manage application started");
946 ret
= create_thread_poll_set(&events
, 2);
951 ret
= lttng_poll_add(&events
, apps_cmd_pipe
[0], LPOLLIN
| LPOLLRDHUP
);
957 /* Zeroed the events structure */
958 lttng_poll_reset(&events
);
960 nb_fd
= LTTNG_POLL_GETNB(&events
);
962 DBG("Apps thread polling on %d fds", nb_fd
);
964 /* Inifinite blocking call, waiting for transmission */
965 ret
= lttng_poll_wait(&events
, -1);
970 for (i
= 0; i
< nb_fd
; i
++) {
971 /* Fetch once the poll data */
972 revents
= LTTNG_POLL_GETEV(&events
, i
);
973 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
975 /* Thread quit pipe has been closed. Killing thread. */
976 ret
= check_thread_quit_pipe(pollfd
, revents
);
981 /* Inspect the apps cmd pipe */
982 if (pollfd
== apps_cmd_pipe
[0]) {
983 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
984 ERR("Apps command pipe error");
986 } else if (revents
& LPOLLIN
) {
988 ret
= read(apps_cmd_pipe
[0], &ust_cmd
, sizeof(ust_cmd
));
989 if (ret
< 0 || ret
< sizeof(ust_cmd
)) {
990 perror("read apps cmd pipe");
994 /* Register applicaton to the session daemon */
995 ret
= ust_app_register(&ust_cmd
.reg_msg
,
998 /* Only critical ENOMEM error can be returned here */
1002 ret
= ustctl_register_done(ust_cmd
.sock
);
1005 * If the registration is not possible, we simply
1006 * unregister the apps and continue
1008 ust_app_unregister(ust_cmd
.sock
);
1011 * We just need here to monitor the close of the UST
1012 * socket and poll set monitor those by default.
1014 ret
= lttng_poll_add(&events
, ust_cmd
.sock
, 0);
1019 DBG("Apps with sock %d added to poll set",
1026 * At this point, we know that a registered application made
1027 * the event at poll_wait.
1029 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1030 /* Removing from the poll set */
1031 ret
= lttng_poll_del(&events
, pollfd
);
1037 ust_app_unregister(pollfd
);
1045 DBG("Application communication apps dying");
1046 close(apps_cmd_pipe
[0]);
1047 close(apps_cmd_pipe
[1]);
1049 lttng_poll_clean(&events
);
1055 * Dispatch request from the registration threads to the application
1056 * communication thread.
1058 static void *thread_dispatch_ust_registration(void *data
)
1061 struct cds_wfq_node
*node
;
1062 struct ust_command
*ust_cmd
= NULL
;
1064 DBG("[thread] Dispatch UST command started");
1066 while (!dispatch_thread_exit
) {
1067 /* Atomically prepare the queue futex */
1068 futex_nto1_prepare(&ust_cmd_queue
.futex
);
1071 /* Dequeue command for registration */
1072 node
= cds_wfq_dequeue_blocking(&ust_cmd_queue
.queue
);
1074 DBG("Waked up but nothing in the UST command queue");
1075 /* Continue thread execution */
1079 ust_cmd
= caa_container_of(node
, struct ust_command
, node
);
1081 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1082 " gid:%d sock:%d name:%s (version %d.%d)",
1083 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1084 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1085 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1086 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1088 * Inform apps thread of the new application registration. This
1089 * call is blocking so we can be assured that the data will be read
1090 * at some point in time or wait to the end of the world :)
1092 ret
= write(apps_cmd_pipe
[1], ust_cmd
,
1093 sizeof(struct ust_command
));
1095 perror("write apps cmd pipe");
1096 if (errno
== EBADF
) {
1098 * We can't inform the application thread to process
1099 * registration. We will exit or else application
1100 * registration will not occur and tracing will never
1107 } while (node
!= NULL
);
1109 /* Futex wait on queue. Blocking call on futex() */
1110 futex_nto1_wait(&ust_cmd_queue
.futex
);
1114 DBG("Dispatch thread dying");
1119 * This thread manage application registration.
1121 static void *thread_registration_apps(void *data
)
1123 int sock
= 0, i
, ret
, pollfd
;
1124 uint32_t revents
, nb_fd
;
1125 struct lttng_poll_event events
;
1127 * Get allocated in this thread, enqueued to a global queue, dequeued and
1128 * freed in the manage apps thread.
1130 struct ust_command
*ust_cmd
= NULL
;
1132 DBG("[thread] Manage application registration started");
1134 ret
= lttcomm_listen_unix_sock(apps_sock
);
1140 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1141 * more will be added to this poll set.
1143 ret
= create_thread_poll_set(&events
, 2);
1148 /* Add the application registration socket */
1149 ret
= lttng_poll_add(&events
, apps_sock
, LPOLLIN
| LPOLLRDHUP
);
1154 /* Notify all applications to register */
1155 ret
= notify_ust_apps(1);
1157 ERR("Failed to notify applications or create the wait shared memory.\n"
1158 "Execution continues but there might be problem for already\n"
1159 "running applications that wishes to register.");
1163 DBG("Accepting application registration");
1165 nb_fd
= LTTNG_POLL_GETNB(&events
);
1167 /* Inifinite blocking call, waiting for transmission */
1168 ret
= lttng_poll_wait(&events
, -1);
1173 for (i
= 0; i
< nb_fd
; i
++) {
1174 /* Fetch once the poll data */
1175 revents
= LTTNG_POLL_GETEV(&events
, i
);
1176 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
1178 /* Thread quit pipe has been closed. Killing thread. */
1179 ret
= check_thread_quit_pipe(pollfd
, revents
);
1184 /* Event on the registration socket */
1185 if (pollfd
== apps_sock
) {
1186 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1187 ERR("Register apps socket poll error");
1189 } else if (revents
& LPOLLIN
) {
1190 sock
= lttcomm_accept_unix_sock(apps_sock
);
1195 /* Create UST registration command for enqueuing */
1196 ust_cmd
= malloc(sizeof(struct ust_command
));
1197 if (ust_cmd
== NULL
) {
1198 perror("ust command malloc");
1203 * Using message-based transmissions to ensure we don't
1204 * have to deal with partially received messages.
1206 ret
= lttcomm_recv_unix_sock(sock
, &ust_cmd
->reg_msg
,
1207 sizeof(struct ust_register_msg
));
1208 if (ret
< 0 || ret
< sizeof(struct ust_register_msg
)) {
1210 perror("lttcomm_recv_unix_sock register apps");
1212 ERR("Wrong size received on apps register");
1219 ust_cmd
->sock
= sock
;
1221 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1222 " gid:%d sock:%d name:%s (version %d.%d)",
1223 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1224 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1225 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1226 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1229 * Lock free enqueue the registration request. The red pill
1230 * has been taken! This apps will be part of the *system*.
1232 cds_wfq_enqueue(&ust_cmd_queue
.queue
, &ust_cmd
->node
);
1235 * Wake the registration queue futex. Implicit memory
1236 * barrier with the exchange in cds_wfq_enqueue.
1238 futex_nto1_wake(&ust_cmd_queue
.futex
);
1245 DBG("UST Registration thread dying");
1247 /* Notify that the registration thread is gone */
1252 unlink(apps_unix_sock_path
);
1254 lttng_poll_clean(&events
);
1260 * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
1261 * exec or it will fails.
1263 static int spawn_kconsumerd_thread(void)
1267 /* Setup semaphore */
1268 sem_init(&kconsumerd_sem
, 0, 0);
1270 ret
= pthread_create(&kconsumerd_thread
, NULL
,
1271 thread_manage_kconsumerd
, (void *) NULL
);
1273 perror("pthread_create kconsumerd");
1277 /* Wait for the kconsumerd thread to be ready */
1278 sem_wait(&kconsumerd_sem
);
1280 if (kconsumerd_pid
== 0) {
1281 ERR("Kconsumerd did not start");
1288 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1293 * Join kernel consumer thread
1295 static int join_kconsumerd_thread(void)
1300 if (kconsumerd_pid
!= 0) {
1301 ret
= kill(kconsumerd_pid
, SIGTERM
);
1303 ERR("Error killing kconsumerd");
1306 return pthread_join(kconsumerd_thread
, &status
);
1313 * Fork and exec a kernel consumer daemon (kconsumerd).
1315 * Return pid if successful else -1.
1317 static pid_t
spawn_kconsumerd(void)
1321 const char *verbosity
;
1323 DBG("Spawning kconsumerd");
1330 if (opt_verbose
> 1 || opt_verbose_kconsumerd
) {
1331 verbosity
= "--verbose";
1333 verbosity
= "--quiet";
1335 execl(INSTALL_BIN_PATH
"/ltt-kconsumerd",
1336 "ltt-kconsumerd", verbosity
, NULL
);
1338 perror("kernel start consumer exec");
1341 } else if (pid
> 0) {
1345 perror("kernel start consumer fork");
1355 * Spawn the kconsumerd daemon and session daemon thread.
1357 static int start_kconsumerd(void)
1361 pthread_mutex_lock(&kconsumerd_pid_mutex
);
1362 if (kconsumerd_pid
!= 0) {
1363 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1367 ret
= spawn_kconsumerd();
1369 ERR("Spawning kconsumerd failed");
1370 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1371 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1375 /* Setting up the global kconsumerd_pid */
1376 kconsumerd_pid
= ret
;
1377 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1379 DBG("Kconsumerd pid %d", ret
);
1381 DBG("Spawning kconsumerd thread");
1382 ret
= spawn_kconsumerd_thread();
1384 ERR("Fatal error spawning kconsumerd thread");
1396 * modprobe_kernel_modules
1398 static int modprobe_kernel_modules(void)
1403 for (i
= 0; i
< ARRAY_SIZE(kernel_modules_list
); i
++) {
1404 ret
= snprintf(modprobe
, sizeof(modprobe
),
1405 "/sbin/modprobe %s%s",
1406 kernel_modules_list
[i
].required
? "" : "--quiet ",
1407 kernel_modules_list
[i
].name
);
1409 perror("snprintf modprobe");
1412 modprobe
[sizeof(modprobe
) - 1] = '\0';
1413 ret
= system(modprobe
);
1415 ERR("Unable to launch modprobe for module %s",
1416 kernel_modules_list
[i
].name
);
1417 } else if (kernel_modules_list
[i
].required
1418 && WEXITSTATUS(ret
) != 0) {
1419 ERR("Unable to load module %s",
1420 kernel_modules_list
[i
].name
);
1422 DBG("Modprobe successfully %s",
1423 kernel_modules_list
[i
].name
);
1434 static int mount_debugfs(char *path
)
1437 char *type
= "debugfs";
1439 ret
= mkdir_recursive(path
, S_IRWXU
| S_IRWXG
, geteuid(), getegid());
1441 PERROR("Cannot create debugfs path");
1445 ret
= mount(type
, path
, type
, 0, NULL
);
1447 PERROR("Cannot mount debugfs");
1451 DBG("Mounted debugfs successfully at %s", path
);
1458 * Setup necessary data for kernel tracer action.
1460 static void init_kernel_tracer(void)
1463 char *proc_mounts
= "/proc/mounts";
1465 char *debugfs_path
= NULL
, *lttng_path
= NULL
;
1468 /* Detect debugfs */
1469 fp
= fopen(proc_mounts
, "r");
1471 ERR("Unable to probe %s", proc_mounts
);
1475 while (fgets(line
, sizeof(line
), fp
) != NULL
) {
1476 if (strstr(line
, "debugfs") != NULL
) {
1477 /* Remove first string */
1479 /* Dup string here so we can reuse line later on */
1480 debugfs_path
= strdup(strtok(NULL
, " "));
1481 DBG("Got debugfs path : %s", debugfs_path
);
1488 /* Mount debugfs if needded */
1489 if (debugfs_path
== NULL
) {
1490 ret
= asprintf(&debugfs_path
, "/mnt/debugfs");
1492 perror("asprintf debugfs path");
1495 ret
= mount_debugfs(debugfs_path
);
1497 perror("Cannot mount debugfs");
1502 /* Modprobe lttng kernel modules */
1503 ret
= modprobe_kernel_modules();
1508 /* Setup lttng kernel path */
1509 ret
= asprintf(<tng_path
, "%s/lttng", debugfs_path
);
1511 perror("asprintf lttng path");
1515 /* Open debugfs lttng */
1516 kernel_tracer_fd
= open(lttng_path
, O_RDWR
);
1517 if (kernel_tracer_fd
< 0) {
1518 DBG("Failed to open %s", lttng_path
);
1524 DBG("Kernel tracer fd %d", kernel_tracer_fd
);
1534 WARN("No kernel tracer available");
1535 kernel_tracer_fd
= 0;
1540 * Init tracing by creating trace directory and sending fds kernel consumer.
1542 static int init_kernel_tracing(struct ltt_kernel_session
*session
)
1546 if (session
->kconsumer_fds_sent
== 0) {
1548 * Assign default kernel consumer socket if no consumer assigned to the
1549 * kernel session. At this point, it's NOT suppose to be 0 but this is
1550 * an extra security check.
1552 if (session
->consumer_fd
== 0) {
1553 session
->consumer_fd
= kconsumerd_cmd_sock
;
1556 ret
= send_kconsumerd_fds(session
);
1558 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1562 session
->kconsumer_fds_sent
= 1;
1570 * Create an UST session and add it to the session ust list.
1572 static int create_ust_session(struct ltt_session
*session
,
1573 struct lttng_domain
*domain
)
1576 struct ltt_ust_session
*lus
;
1577 struct ust_app
*app
;
1579 switch (domain
->type
) {
1580 case LTTNG_DOMAIN_UST_PID
:
1581 app
= ust_app_get_by_pid(domain
->attr
.pid
);
1583 ret
= LTTCOMM_APP_NOT_FOUND
;
1591 DBG("Creating UST session");
1593 lus
= trace_ust_create_session(session
->path
, domain
->attr
.pid
, domain
);
1595 ret
= LTTCOMM_UST_SESS_FAIL
;
1599 ret
= mkdir_recursive(lus
->path
, S_IRWXU
| S_IRWXG
,
1600 geteuid(), allowed_group());
1602 if (ret
!= -EEXIST
) {
1603 ERR("Trace directory creation error");
1604 ret
= LTTCOMM_UST_SESS_FAIL
;
1609 /* Create session on the UST tracer */
1610 ret
= ustctl_create_session(app
->sock
, lus
);
1612 ret
= LTTCOMM_UST_SESS_FAIL
;
1616 cds_list_add(&lus
->list
, &session
->ust_session_list
.head
);
1617 session
->ust_session_list
.count
++;
1627 * Create a kernel tracer session then create the default channel.
1629 static int create_kernel_session(struct ltt_session
*session
)
1633 DBG("Creating kernel session");
1635 ret
= kernel_create_session(session
, kernel_tracer_fd
);
1637 ret
= LTTCOMM_KERN_SESS_FAIL
;
1641 /* Set kernel consumer socket fd */
1642 if (kconsumerd_cmd_sock
) {
1643 session
->kernel_session
->consumer_fd
= kconsumerd_cmd_sock
;
1646 ret
= mkdir_recursive(session
->kernel_session
->trace_path
,
1647 S_IRWXU
| S_IRWXG
, geteuid(), allowed_group());
1649 if (ret
!= -EEXIST
) {
1650 ERR("Trace directory creation error");
1660 * Using the session list, filled a lttng_session array to send back to the
1661 * client for session listing.
1663 * The session list lock MUST be acquired before calling this function. Use
1664 * session_lock_list() and session_unlock_list().
1666 static void list_lttng_sessions(struct lttng_session
*sessions
)
1669 struct ltt_session
*session
;
1671 DBG("Getting all available session");
1673 * Iterate over session list and append data after the control struct in
1676 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
1677 strncpy(sessions
[i
].path
, session
->path
, PATH_MAX
);
1678 sessions
[i
].path
[PATH_MAX
- 1] = '\0';
1679 strncpy(sessions
[i
].name
, session
->name
, NAME_MAX
);
1680 sessions
[i
].name
[NAME_MAX
- 1] = '\0';
1686 * Fill lttng_channel array of all channels.
1688 static void list_lttng_channels(struct ltt_session
*session
,
1689 struct lttng_channel
*channels
)
1692 struct ltt_kernel_channel
*kchan
;
1694 DBG("Listing channels for session %s", session
->name
);
1696 /* Kernel channels */
1697 if (session
->kernel_session
!= NULL
) {
1698 cds_list_for_each_entry(kchan
,
1699 &session
->kernel_session
->channel_list
.head
, list
) {
1700 /* Copy lttng_channel struct to array */
1701 memcpy(&channels
[i
], kchan
->channel
, sizeof(struct lttng_channel
));
1702 channels
[i
].enabled
= kchan
->enabled
;
1707 /* TODO: Missing UST listing */
1711 * Fill lttng_event array of all events in the channel.
1713 static void list_lttng_events(struct ltt_kernel_channel
*kchan
,
1714 struct lttng_event
*events
)
1717 * TODO: This is ONLY kernel. Need UST support.
1720 struct ltt_kernel_event
*event
;
1722 DBG("Listing events for channel %s", kchan
->channel
->name
);
1724 /* Kernel channels */
1725 cds_list_for_each_entry(event
, &kchan
->events_list
.head
, list
) {
1726 strncpy(events
[i
].name
, event
->event
->name
, LTTNG_SYMBOL_NAME_LEN
);
1727 events
[i
].name
[LTTNG_SYMBOL_NAME_LEN
- 1] = '\0';
1728 events
[i
].enabled
= event
->enabled
;
1729 switch (event
->event
->instrumentation
) {
1730 case LTTNG_KERNEL_TRACEPOINT
:
1731 events
[i
].type
= LTTNG_EVENT_TRACEPOINT
;
1733 case LTTNG_KERNEL_KPROBE
:
1734 case LTTNG_KERNEL_KRETPROBE
:
1735 events
[i
].type
= LTTNG_EVENT_PROBE
;
1736 memcpy(&events
[i
].attr
.probe
, &event
->event
->u
.kprobe
,
1737 sizeof(struct lttng_kernel_kprobe
));
1739 case LTTNG_KERNEL_FUNCTION
:
1740 events
[i
].type
= LTTNG_EVENT_FUNCTION
;
1741 memcpy(&events
[i
].attr
.ftrace
, &event
->event
->u
.ftrace
,
1742 sizeof(struct lttng_kernel_function
));
1744 case LTTNG_KERNEL_NOOP
:
1745 events
[i
].type
= LTTNG_EVENT_NOOP
;
1747 case LTTNG_KERNEL_SYSCALL
:
1748 events
[i
].type
= LTTNG_EVENT_SYSCALL
;
1750 case LTTNG_KERNEL_ALL
:
1759 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1761 static int cmd_disable_channel(struct ltt_session
*session
,
1762 int domain
, char *channel_name
)
1767 case LTTNG_DOMAIN_KERNEL
:
1768 ret
= channel_kernel_disable(session
->kernel_session
,
1770 if (ret
!= LTTCOMM_OK
) {
1774 kernel_wait_quiescent(kernel_tracer_fd
);
1776 case LTTNG_DOMAIN_UST_PID
:
1779 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
1790 * Copy channel from attributes and set it in the application channel list.
1792 static int copy_ust_channel_to_app(struct ltt_ust_session
*usess
,
1793 struct lttng_channel
*attr
, struct ust_app
*app
)
1796 struct ltt_ust_channel
*uchan
, *new_chan
;
1798 uchan
= trace_ust_get_channel_by_name(attr
->name
, usess
);
1799 if (uchan
== NULL
) {
1800 ret
= LTTCOMM_FATAL
;
1804 new_chan
= trace_ust_create_channel(attr
, usess
->path
);
1805 if (new_chan
== NULL
) {
1806 PERROR("malloc ltt_ust_channel");
1807 ret
= LTTCOMM_FATAL
;
1811 ret
= channel_ust_copy(new_chan
, uchan
);
1813 ret
= LTTCOMM_FATAL
;
1817 /* Add channel to the ust app channel list */
1818 cds_list_add(&new_chan
->list
, &app
->channels
.head
);
1819 app
->channels
.count
++;
1826 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1828 static int cmd_enable_channel(struct ltt_session
*session
,
1829 struct lttng_domain
*domain
, struct lttng_channel
*attr
)
1833 switch (domain
->type
) {
1834 case LTTNG_DOMAIN_KERNEL
:
1836 struct ltt_kernel_channel
*kchan
;
1838 kchan
= trace_kernel_get_channel_by_name(attr
->name
,
1839 session
->kernel_session
);
1840 if (kchan
== NULL
) {
1841 ret
= channel_kernel_create(session
->kernel_session
,
1842 attr
, kernel_poll_pipe
[1]);
1844 ret
= channel_kernel_enable(session
->kernel_session
, kchan
);
1847 if (ret
!= LTTCOMM_OK
) {
1851 kernel_wait_quiescent(kernel_tracer_fd
);
1854 case LTTNG_DOMAIN_UST_PID
:
1857 struct ltt_ust_channel
*uchan
;
1858 struct ltt_ust_session
*usess
;
1859 struct ust_app
*app
;
1861 usess
= trace_ust_get_session_by_pid(&session
->ust_session_list
,
1863 if (usess
== NULL
) {
1864 ret
= LTTCOMM_UST_CHAN_NOT_FOUND
;
1868 app
= ust_app_get_by_pid(domain
->attr
.pid
);
1870 ret
= LTTCOMM_APP_NOT_FOUND
;
1875 uchan
= trace_ust_get_channel_by_name(attr
->name
, usess
);
1876 if (uchan
== NULL
) {
1877 ret
= channel_ust_create(usess
, attr
, sock
);
1879 ret
= channel_ust_enable(usess
, uchan
, sock
);
1882 if (ret
!= LTTCOMM_OK
) {
1886 ret
= copy_ust_channel_to_app(usess
, attr
, app
);
1887 if (ret
!= LTTCOMM_OK
) {
1891 DBG("UST channel %s created for app sock %d with pid %d",
1892 attr
->name
, app
->sock
, domain
->attr
.pid
);
1896 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
1907 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1909 static int cmd_disable_event(struct ltt_session
*session
, int domain
,
1910 char *channel_name
, char *event_name
)
1913 struct ltt_kernel_channel
*kchan
;
1916 case LTTNG_DOMAIN_KERNEL
:
1917 kchan
= trace_kernel_get_channel_by_name(channel_name
,
1918 session
->kernel_session
);
1919 if (kchan
== NULL
) {
1920 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
1924 ret
= event_kernel_disable_tracepoint(session
->kernel_session
, kchan
, event_name
);
1925 if (ret
!= LTTCOMM_OK
) {
1929 kernel_wait_quiescent(kernel_tracer_fd
);
1932 /* TODO: Userspace tracing */
1933 ret
= LTTCOMM_NOT_IMPLEMENTED
;
1944 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
1946 static int cmd_disable_event_all(struct ltt_session
*session
, int domain
,
1950 struct ltt_kernel_channel
*kchan
;
1953 case LTTNG_DOMAIN_KERNEL
:
1954 kchan
= trace_kernel_get_channel_by_name(channel_name
,
1955 session
->kernel_session
);
1956 if (kchan
== NULL
) {
1957 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
1961 ret
= event_kernel_disable_all(session
->kernel_session
, kchan
);
1962 if (ret
!= LTTCOMM_OK
) {
1966 kernel_wait_quiescent(kernel_tracer_fd
);
1969 /* TODO: Userspace tracing */
1970 ret
= LTTCOMM_NOT_IMPLEMENTED
;
1981 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1983 static int cmd_add_context(struct ltt_session
*session
, int domain
,
1984 char *channel_name
, char *event_name
, struct lttng_event_context
*ctx
)
1989 case LTTNG_DOMAIN_KERNEL
:
1990 /* Add kernel context to kernel tracer */
1991 ret
= context_kernel_add(session
->kernel_session
, ctx
,
1992 event_name
, channel_name
);
1993 if (ret
!= LTTCOMM_OK
) {
1999 /* TODO: Userspace tracing */
2000 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2011 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2013 static int cmd_enable_event(struct ltt_session
*session
, int domain
,
2014 char *channel_name
, struct lttng_event
*event
)
2017 struct ltt_kernel_channel
*kchan
;
2020 case LTTNG_DOMAIN_KERNEL
:
2021 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2022 session
->kernel_session
);
2023 if (kchan
== NULL
) {
2024 /* This call will notify the kernel thread */
2025 ret
= channel_kernel_create(session
->kernel_session
,
2026 NULL
, kernel_poll_pipe
[1]);
2027 if (ret
!= LTTCOMM_OK
) {
2032 /* Get the newly created kernel channel pointer */
2033 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2034 session
->kernel_session
);
2035 if (kchan
== NULL
) {
2036 /* This sould not happen... */
2037 ret
= LTTCOMM_FATAL
;
2041 ret
= event_kernel_enable_tracepoint(session
->kernel_session
, kchan
, event
);
2042 if (ret
!= LTTCOMM_OK
) {
2046 kernel_wait_quiescent(kernel_tracer_fd
);
2049 /* TODO: Userspace tracing */
2050 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2061 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2063 static int cmd_enable_event_all(struct ltt_session
*session
, int domain
,
2064 char *channel_name
, int event_type
)
2067 struct ltt_kernel_channel
*kchan
;
2070 case LTTNG_DOMAIN_KERNEL
:
2071 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2072 session
->kernel_session
);
2073 if (kchan
== NULL
) {
2074 /* This call will notify the kernel thread */
2075 ret
= channel_kernel_create(session
->kernel_session
, NULL
,
2076 kernel_poll_pipe
[1]);
2077 if (ret
!= LTTCOMM_OK
) {
2082 /* Get the newly created kernel channel pointer */
2083 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2084 session
->kernel_session
);
2085 if (kchan
== NULL
) {
2086 /* This sould not happen... */
2087 ret
= LTTCOMM_FATAL
;
2091 switch (event_type
) {
2092 case LTTNG_KERNEL_SYSCALL
:
2093 ret
= event_kernel_enable_all_syscalls(session
->kernel_session
,
2094 kchan
, kernel_tracer_fd
);
2096 case LTTNG_KERNEL_TRACEPOINT
:
2098 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2099 * events already registered to the channel.
2101 ret
= event_kernel_enable_all_tracepoints(session
->kernel_session
,
2102 kchan
, kernel_tracer_fd
);
2104 case LTTNG_KERNEL_ALL
:
2105 /* Enable syscalls and tracepoints */
2106 ret
= event_kernel_enable_all(session
->kernel_session
,
2107 kchan
, kernel_tracer_fd
);
2110 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2113 if (ret
!= LTTCOMM_OK
) {
2117 kernel_wait_quiescent(kernel_tracer_fd
);
2120 /* TODO: Userspace tracing */
2121 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2132 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2134 static ssize_t
cmd_list_tracepoints(int domain
, struct lttng_event
**events
)
2137 ssize_t nb_events
= 0;
2140 case LTTNG_DOMAIN_KERNEL
:
2141 nb_events
= kernel_list_events(kernel_tracer_fd
, events
);
2142 if (nb_events
< 0) {
2143 ret
= LTTCOMM_KERN_LIST_FAIL
;
2148 /* TODO: Userspace listing */
2149 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2156 /* Return negative value to differentiate return code */
2161 * Command LTTNG_START_TRACE processed by the client thread.
2163 static int cmd_start_trace(struct ltt_session
*session
)
2166 struct ltt_kernel_channel
*kchan
;
2167 struct ltt_kernel_session
*ksession
;
2170 ksession
= session
->kernel_session
;
2172 /* Kernel tracing */
2173 if (ksession
!= NULL
) {
2174 /* Open kernel metadata */
2175 if (ksession
->metadata
== NULL
) {
2176 ret
= kernel_open_metadata(ksession
, ksession
->trace_path
);
2178 ret
= LTTCOMM_KERN_META_FAIL
;
2183 /* Open kernel metadata stream */
2184 if (ksession
->metadata_stream_fd
== 0) {
2185 ret
= kernel_open_metadata_stream(ksession
);
2187 ERR("Kernel create metadata stream failed");
2188 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2193 /* For each channel */
2194 cds_list_for_each_entry(kchan
, &ksession
->channel_list
.head
, list
) {
2195 if (kchan
->stream_count
== 0) {
2196 ret
= kernel_open_channel_stream(kchan
);
2198 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2201 /* Update the stream global counter */
2202 ksession
->stream_count_global
+= ret
;
2206 /* Setup kernel consumer socket and send fds to it */
2207 ret
= init_kernel_tracing(ksession
);
2209 ret
= LTTCOMM_KERN_START_FAIL
;
2213 /* This start the kernel tracing */
2214 ret
= kernel_start_session(ksession
);
2216 ret
= LTTCOMM_KERN_START_FAIL
;
2220 /* Quiescent wait after starting trace */
2221 kernel_wait_quiescent(kernel_tracer_fd
);
2224 /* TODO: Start all UST traces */
2233 * Command LTTNG_STOP_TRACE processed by the client thread.
2235 static int cmd_stop_trace(struct ltt_session
*session
)
2238 struct ltt_kernel_channel
*kchan
;
2239 struct ltt_kernel_session
*ksession
;
2242 ksession
= session
->kernel_session
;
2245 if (ksession
!= NULL
) {
2246 DBG("Stop kernel tracing");
2248 /* Flush all buffers before stopping */
2249 ret
= kernel_metadata_flush_buffer(ksession
->metadata_stream_fd
);
2251 ERR("Kernel metadata flush failed");
2254 cds_list_for_each_entry(kchan
, &ksession
->channel_list
.head
, list
) {
2255 ret
= kernel_flush_buffer(kchan
);
2257 ERR("Kernel flush buffer error");
2261 ret
= kernel_stop_session(ksession
);
2263 ret
= LTTCOMM_KERN_STOP_FAIL
;
2267 kernel_wait_quiescent(kernel_tracer_fd
);
2270 /* TODO : User-space tracer */
2279 * Command LTTNG_CREATE_SESSION processed by the client thread.
2281 static int cmd_create_session(char *name
, char *path
)
2285 ret
= session_create(name
, path
);
2286 if (ret
!= LTTCOMM_OK
) {
2297 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2299 static int cmd_destroy_session(struct ltt_session
*session
, char *name
)
2303 /* Clean kernel session teardown */
2304 teardown_kernel_session(session
);
2307 * Must notify the kernel thread here to update it's poll setin order
2308 * to remove the channel(s)' fd just destroyed.
2310 ret
= notify_thread_pipe(kernel_poll_pipe
[1]);
2312 perror("write kernel poll pipe");
2315 ret
= session_destroy(name
);
2321 * Command LTTNG_CALIBRATE processed by the client thread.
2323 static int cmd_calibrate(int domain
, struct lttng_calibrate
*calibrate
)
2328 case LTTNG_DOMAIN_KERNEL
:
2330 struct lttng_kernel_calibrate kcalibrate
;
2332 kcalibrate
.type
= calibrate
->type
;
2333 ret
= kernel_calibrate(kernel_tracer_fd
, &kcalibrate
);
2335 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2341 /* TODO: Userspace tracing */
2342 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2353 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2355 static int cmd_register_consumer(struct ltt_session
*session
, int domain
,
2361 case LTTNG_DOMAIN_KERNEL
:
2362 /* Can't register a consumer if there is already one */
2363 if (session
->kernel_session
->consumer_fd
!= 0) {
2364 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
2368 sock
= lttcomm_connect_unix_sock(sock_path
);
2370 ret
= LTTCOMM_CONNECT_FAIL
;
2374 session
->kernel_session
->consumer_fd
= sock
;
2377 /* TODO: Userspace tracing */
2378 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2389 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2391 static ssize_t
cmd_list_domains(struct ltt_session
*session
,
2392 struct lttng_domain
**domains
)
2397 if (session
->kernel_session
!= NULL
) {
2401 nb_dom
+= session
->ust_session_list
.count
;
2403 *domains
= malloc(nb_dom
* sizeof(struct lttng_domain
));
2404 if (*domains
== NULL
) {
2405 ret
= -LTTCOMM_FATAL
;
2409 (*domains
)[0].type
= LTTNG_DOMAIN_KERNEL
;
2411 /* TODO: User-space tracer domain support */
2420 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2422 static ssize_t
cmd_list_channels(struct ltt_session
*session
,
2423 struct lttng_channel
**channels
)
2426 ssize_t nb_chan
= 0;
2428 if (session
->kernel_session
!= NULL
) {
2429 nb_chan
+= session
->kernel_session
->channel_count
;
2432 *channels
= malloc(nb_chan
* sizeof(struct lttng_channel
));
2433 if (*channels
== NULL
) {
2434 ret
= -LTTCOMM_FATAL
;
2438 list_lttng_channels(session
, *channels
);
2447 * Command LTTNG_LIST_EVENTS processed by the client thread.
2449 static ssize_t
cmd_list_events(struct ltt_session
*session
,
2450 char *channel_name
, struct lttng_event
**events
)
2453 ssize_t nb_event
= 0;
2454 struct ltt_kernel_channel
*kchan
= NULL
;
2456 if (session
->kernel_session
!= NULL
) {
2457 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2458 session
->kernel_session
);
2459 if (kchan
== NULL
) {
2460 ret
= -LTTCOMM_KERN_CHAN_NOT_FOUND
;
2463 nb_event
+= kchan
->event_count
;
2466 *events
= malloc(nb_event
* sizeof(struct lttng_event
));
2467 if (*events
== NULL
) {
2468 ret
= -LTTCOMM_FATAL
;
2472 list_lttng_events(kchan
, *events
);
2474 /* TODO: User-space tracer support */
2483 * Process the command requested by the lttng client within the command
2484 * context structure. This function make sure that the return structure (llm)
2485 * is set and ready for transmission before returning.
2487 * Return any error encountered or 0 for success.
2489 static int process_client_msg(struct command_ctx
*cmd_ctx
)
2491 int ret
= LTTCOMM_OK
;
2492 int need_tracing_session
= 1;
2494 DBG("Processing client command %d", cmd_ctx
->lsm
->cmd_type
);
2497 * Check for command that don't needs to allocate a returned payload. We do
2498 * this here so we don't have to make the call for no payload at each
2501 switch(cmd_ctx
->lsm
->cmd_type
) {
2502 case LTTNG_LIST_SESSIONS
:
2503 case LTTNG_LIST_TRACEPOINTS
:
2504 case LTTNG_LIST_DOMAINS
:
2505 case LTTNG_LIST_CHANNELS
:
2506 case LTTNG_LIST_EVENTS
:
2509 /* Setup lttng message with no payload */
2510 ret
= setup_lttng_msg(cmd_ctx
, 0);
2512 /* This label does not try to unlock the session */
2513 goto init_setup_error
;
2517 /* Commands that DO NOT need a session. */
2518 switch (cmd_ctx
->lsm
->cmd_type
) {
2519 case LTTNG_CALIBRATE
:
2520 case LTTNG_CREATE_SESSION
:
2521 case LTTNG_LIST_SESSIONS
:
2522 case LTTNG_LIST_TRACEPOINTS
:
2523 need_tracing_session
= 0;
2526 DBG("Getting session %s by name", cmd_ctx
->lsm
->session
.name
);
2527 cmd_ctx
->session
= session_find_by_name(cmd_ctx
->lsm
->session
.name
);
2528 if (cmd_ctx
->session
== NULL
) {
2529 if (cmd_ctx
->lsm
->session
.name
!= NULL
) {
2530 ret
= LTTCOMM_SESS_NOT_FOUND
;
2532 /* If no session name specified */
2533 ret
= LTTCOMM_SELECT_SESS
;
2537 /* Acquire lock for the session */
2538 session_lock(cmd_ctx
->session
);
2544 * Check domain type for specific "pre-action".
2546 switch (cmd_ctx
->lsm
->domain
.type
) {
2547 case LTTNG_DOMAIN_KERNEL
:
2548 /* Kernel tracer check */
2549 if (kernel_tracer_fd
== 0) {
2550 /* Basically, load kernel tracer modules */
2551 init_kernel_tracer();
2552 if (kernel_tracer_fd
== 0) {
2553 ret
= LTTCOMM_KERN_NA
;
2558 /* Need a session for kernel command */
2559 if (need_tracing_session
) {
2560 if (cmd_ctx
->session
->kernel_session
== NULL
) {
2561 ret
= create_kernel_session(cmd_ctx
->session
);
2563 ret
= LTTCOMM_KERN_SESS_FAIL
;
2568 /* Start the kernel consumer daemon */
2569 if (kconsumerd_pid
== 0 &&
2570 cmd_ctx
->lsm
->cmd_type
!= LTTNG_REGISTER_CONSUMER
) {
2571 ret
= start_kconsumerd();
2573 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
2579 case LTTNG_DOMAIN_UST_PID
:
2581 struct ltt_ust_session
*usess
;
2583 if (need_tracing_session
) {
2584 usess
= trace_ust_get_session_by_pid(
2585 &cmd_ctx
->session
->ust_session_list
,
2586 cmd_ctx
->lsm
->domain
.attr
.pid
);
2587 if (usess
== NULL
) {
2588 ret
= create_ust_session(cmd_ctx
->session
,
2589 &cmd_ctx
->lsm
->domain
);
2590 if (ret
!= LTTCOMM_OK
) {
2598 /* TODO Userspace tracer */
2602 /* Process by command type */
2603 switch (cmd_ctx
->lsm
->cmd_type
) {
2604 case LTTNG_ADD_CONTEXT
:
2606 ret
= cmd_add_context(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2607 cmd_ctx
->lsm
->u
.context
.channel_name
,
2608 cmd_ctx
->lsm
->u
.context
.event_name
,
2609 &cmd_ctx
->lsm
->u
.context
.ctx
);
2612 case LTTNG_DISABLE_CHANNEL
:
2614 ret
= cmd_disable_channel(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2615 cmd_ctx
->lsm
->u
.disable
.channel_name
);
2618 case LTTNG_DISABLE_EVENT
:
2620 ret
= cmd_disable_event(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2621 cmd_ctx
->lsm
->u
.disable
.channel_name
,
2622 cmd_ctx
->lsm
->u
.disable
.name
);
2626 case LTTNG_DISABLE_ALL_EVENT
:
2628 DBG("Disabling all kernel event");
2630 ret
= cmd_disable_event_all(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2631 cmd_ctx
->lsm
->u
.disable
.channel_name
);
2634 case LTTNG_ENABLE_CHANNEL
:
2636 ret
= cmd_enable_channel(cmd_ctx
->session
, &cmd_ctx
->lsm
->domain
,
2637 &cmd_ctx
->lsm
->u
.channel
.chan
);
2640 case LTTNG_ENABLE_EVENT
:
2642 ret
= cmd_enable_event(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2643 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2644 &cmd_ctx
->lsm
->u
.enable
.event
);
2647 case LTTNG_ENABLE_ALL_EVENT
:
2649 DBG("Enabling all kernel event");
2651 ret
= cmd_enable_event_all(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2652 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2653 cmd_ctx
->lsm
->u
.enable
.event
.type
);
2656 case LTTNG_LIST_TRACEPOINTS
:
2658 struct lttng_event
*events
;
2661 nb_events
= cmd_list_tracepoints(cmd_ctx
->lsm
->domain
.type
, &events
);
2662 if (nb_events
< 0) {
2668 * Setup lttng message with payload size set to the event list size in
2669 * bytes and then copy list into the llm payload.
2671 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_event
) * nb_events
);
2677 /* Copy event list into message payload */
2678 memcpy(cmd_ctx
->llm
->payload
, events
,
2679 sizeof(struct lttng_event
) * nb_events
);
2686 case LTTNG_START_TRACE
:
2688 ret
= cmd_start_trace(cmd_ctx
->session
);
2691 case LTTNG_STOP_TRACE
:
2693 ret
= cmd_stop_trace(cmd_ctx
->session
);
2696 case LTTNG_CREATE_SESSION
:
2698 ret
= cmd_create_session(cmd_ctx
->lsm
->session
.name
,
2699 cmd_ctx
->lsm
->session
.path
);
2702 case LTTNG_DESTROY_SESSION
:
2704 ret
= cmd_destroy_session(cmd_ctx
->session
,
2705 cmd_ctx
->lsm
->session
.name
);
2708 case LTTNG_LIST_DOMAINS
:
2711 struct lttng_domain
*domains
;
2713 nb_dom
= cmd_list_domains(cmd_ctx
->session
, &domains
);
2719 ret
= setup_lttng_msg(cmd_ctx
, nb_dom
* sizeof(struct lttng_domain
));
2724 /* Copy event list into message payload */
2725 memcpy(cmd_ctx
->llm
->payload
, domains
,
2726 nb_dom
* sizeof(struct lttng_domain
));
2733 case LTTNG_LIST_CHANNELS
:
2736 struct lttng_channel
*channels
;
2738 nb_chan
= cmd_list_channels(cmd_ctx
->session
, &channels
);
2744 ret
= setup_lttng_msg(cmd_ctx
, nb_chan
* sizeof(struct lttng_channel
));
2749 /* Copy event list into message payload */
2750 memcpy(cmd_ctx
->llm
->payload
, channels
,
2751 nb_chan
* sizeof(struct lttng_channel
));
2758 case LTTNG_LIST_EVENTS
:
2761 struct lttng_event
*events
= NULL
;
2763 nb_event
= cmd_list_events(cmd_ctx
->session
,
2764 cmd_ctx
->lsm
->u
.list
.channel_name
, &events
);
2770 ret
= setup_lttng_msg(cmd_ctx
, nb_event
* sizeof(struct lttng_event
));
2775 /* Copy event list into message payload */
2776 memcpy(cmd_ctx
->llm
->payload
, events
,
2777 nb_event
* sizeof(struct lttng_event
));
2784 case LTTNG_LIST_SESSIONS
:
2786 session_lock_list();
2788 if (session_list_ptr
->count
== 0) {
2789 ret
= LTTCOMM_NO_SESSION
;
2790 session_unlock_list();
2794 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_session
) *
2795 session_list_ptr
->count
);
2797 session_unlock_list();
2801 /* Filled the session array */
2802 list_lttng_sessions((struct lttng_session
*)(cmd_ctx
->llm
->payload
));
2804 session_unlock_list();
2809 case LTTNG_CALIBRATE
:
2811 ret
= cmd_calibrate(cmd_ctx
->lsm
->domain
.type
,
2812 &cmd_ctx
->lsm
->u
.calibrate
);
2815 case LTTNG_REGISTER_CONSUMER
:
2817 ret
= cmd_register_consumer(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2818 cmd_ctx
->lsm
->u
.reg
.path
);
2827 if (cmd_ctx
->llm
== NULL
) {
2828 DBG("Missing llm structure. Allocating one.");
2829 if (setup_lttng_msg(cmd_ctx
, 0) < 0) {
2833 /* Set return code */
2834 cmd_ctx
->llm
->ret_code
= ret
;
2836 if (cmd_ctx
->session
) {
2837 session_unlock(cmd_ctx
->session
);
2844 * This thread manage all clients request using the unix client socket for
2847 static void *thread_manage_clients(void *data
)
2849 int sock
= 0, ret
, i
, pollfd
;
2850 uint32_t revents
, nb_fd
;
2851 struct command_ctx
*cmd_ctx
= NULL
;
2852 struct lttng_poll_event events
;
2854 DBG("[thread] Manage client started");
2856 ret
= lttcomm_listen_unix_sock(client_sock
);
2862 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2863 * more will be added to this poll set.
2865 ret
= create_thread_poll_set(&events
, 2);
2870 /* Add the application registration socket */
2871 ret
= lttng_poll_add(&events
, client_sock
, LPOLLIN
| LPOLLPRI
);
2877 * Notify parent pid that we are ready to accept command for client side.
2879 if (opt_sig_parent
) {
2880 kill(ppid
, SIGCHLD
);
2884 DBG("Accepting client command ...");
2886 nb_fd
= LTTNG_POLL_GETNB(&events
);
2888 /* Inifinite blocking call, waiting for transmission */
2889 ret
= lttng_poll_wait(&events
, -1);
2894 for (i
= 0; i
< nb_fd
; i
++) {
2895 /* Fetch once the poll data */
2896 revents
= LTTNG_POLL_GETEV(&events
, i
);
2897 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2899 /* Thread quit pipe has been closed. Killing thread. */
2900 ret
= check_thread_quit_pipe(pollfd
, revents
);
2905 /* Event on the registration socket */
2906 if (pollfd
== client_sock
) {
2907 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
2908 ERR("Client socket poll error");
2914 DBG("Wait for client response");
2916 sock
= lttcomm_accept_unix_sock(client_sock
);
2921 /* Allocate context command to process the client request */
2922 cmd_ctx
= malloc(sizeof(struct command_ctx
));
2923 if (cmd_ctx
== NULL
) {
2924 perror("malloc cmd_ctx");
2928 /* Allocate data buffer for reception */
2929 cmd_ctx
->lsm
= malloc(sizeof(struct lttcomm_session_msg
));
2930 if (cmd_ctx
->lsm
== NULL
) {
2931 perror("malloc cmd_ctx->lsm");
2935 cmd_ctx
->llm
= NULL
;
2936 cmd_ctx
->session
= NULL
;
2939 * Data is received from the lttng client. The struct
2940 * lttcomm_session_msg (lsm) contains the command and data request of
2943 DBG("Receiving data from client ...");
2944 ret
= lttcomm_recv_unix_sock(sock
, cmd_ctx
->lsm
,
2945 sizeof(struct lttcomm_session_msg
));
2947 DBG("Nothing recv() from client... continuing");
2953 // TODO: Validate cmd_ctx including sanity check for
2954 // security purpose.
2957 * This function dispatch the work to the kernel or userspace tracer
2958 * libs and fill the lttcomm_lttng_msg data structure of all the needed
2959 * informations for the client. The command context struct contains
2960 * everything this function may needs.
2962 ret
= process_client_msg(cmd_ctx
);
2965 * TODO: Inform client somehow of the fatal error. At
2966 * this point, ret < 0 means that a malloc failed
2967 * (ENOMEM). Error detected but still accept command.
2969 clean_command_ctx(&cmd_ctx
);
2973 DBG("Sending response (size: %d, retcode: %s)",
2974 cmd_ctx
->lttng_msg_size
,
2975 lttng_get_readable_code(-cmd_ctx
->llm
->ret_code
));
2976 ret
= send_unix_sock(sock
, cmd_ctx
->llm
, cmd_ctx
->lttng_msg_size
);
2978 ERR("Failed to send data back to client");
2981 clean_command_ctx(&cmd_ctx
);
2983 /* End of transmission */
2988 DBG("Client thread dying");
2989 unlink(client_unix_sock_path
);
2993 lttng_poll_clean(&events
);
2994 clean_command_ctx(&cmd_ctx
);
3000 * usage function on stderr
3002 static void usage(void)
3004 fprintf(stderr
, "Usage: %s OPTIONS\n\nOptions:\n", progname
);
3005 fprintf(stderr
, " -h, --help Display this usage.\n");
3006 fprintf(stderr
, " -c, --client-sock PATH Specify path for the client unix socket\n");
3007 fprintf(stderr
, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3008 fprintf(stderr
, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3009 fprintf(stderr
, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3010 fprintf(stderr
, " -d, --daemonize Start as a daemon.\n");
3011 fprintf(stderr
, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3012 fprintf(stderr
, " -V, --version Show version number.\n");
3013 fprintf(stderr
, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3014 fprintf(stderr
, " -q, --quiet No output at all.\n");
3015 fprintf(stderr
, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3016 fprintf(stderr
, " --verbose-kconsumerd Verbose mode for kconsumerd. Activate DBG() macro.\n");
3020 * daemon argument parsing
3022 static int parse_args(int argc
, char **argv
)
3026 static struct option long_options
[] = {
3027 { "client-sock", 1, 0, 'c' },
3028 { "apps-sock", 1, 0, 'a' },
3029 { "kconsumerd-cmd-sock", 1, 0, 0 },
3030 { "kconsumerd-err-sock", 1, 0, 0 },
3031 { "daemonize", 0, 0, 'd' },
3032 { "sig-parent", 0, 0, 'S' },
3033 { "help", 0, 0, 'h' },
3034 { "group", 1, 0, 'g' },
3035 { "version", 0, 0, 'V' },
3036 { "quiet", 0, 0, 'q' },
3037 { "verbose", 0, 0, 'v' },
3038 { "verbose-kconsumerd", 0, 0, 'Z' },
3043 int option_index
= 0;
3044 c
= getopt_long(argc
, argv
, "dhqvVS" "a:c:g:s:E:C:Z",
3045 long_options
, &option_index
);
3052 fprintf(stderr
, "option %s", long_options
[option_index
].name
);
3054 fprintf(stderr
, " with arg %s\n", optarg
);
3058 snprintf(client_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3061 snprintf(apps_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3067 opt_tracing_group
= strdup(optarg
);
3073 fprintf(stdout
, "%s\n", VERSION
);
3079 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3082 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3088 /* Verbose level can increase using multiple -v */
3092 opt_verbose_kconsumerd
+= 1;
3095 /* Unknown option or other error.
3096 * Error is printed by getopt, just return */
3105 * Creates the two needed socket by the daemon.
3106 * apps_sock - The communication socket for all UST apps.
3107 * client_sock - The communication of the cli tool (lttng).
3109 static int init_daemon_socket(void)
3114 old_umask
= umask(0);
3116 /* Create client tool unix socket */
3117 client_sock
= lttcomm_create_unix_sock(client_unix_sock_path
);
3118 if (client_sock
< 0) {
3119 ERR("Create unix sock failed: %s", client_unix_sock_path
);
3124 /* File permission MUST be 660 */
3125 ret
= chmod(client_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3127 ERR("Set file permissions failed: %s", client_unix_sock_path
);
3132 /* Create the application unix socket */
3133 apps_sock
= lttcomm_create_unix_sock(apps_unix_sock_path
);
3134 if (apps_sock
< 0) {
3135 ERR("Create unix sock failed: %s", apps_unix_sock_path
);
3140 /* File permission MUST be 666 */
3141 ret
= chmod(apps_unix_sock_path
,
3142 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
| S_IROTH
| S_IWOTH
);
3144 ERR("Set file permissions failed: %s", apps_unix_sock_path
);
3155 * Check if the global socket is available, and if a daemon is answering at the
3156 * other side. If yes, error is returned.
3158 static int check_existing_daemon(void)
3160 if (access(client_unix_sock_path
, F_OK
) < 0 &&
3161 access(apps_unix_sock_path
, F_OK
) < 0) {
3165 /* Is there anybody out there ? */
3166 if (lttng_session_daemon_alive()) {
3174 * Set the tracing group gid onto the client socket.
3176 * Race window between mkdir and chown is OK because we are going from more
3177 * permissive (root.root) to les permissive (root.tracing).
3179 static int set_permissions(void)
3184 gid
= allowed_group();
3187 WARN("No tracing group detected");
3190 ERR("Missing tracing group. Aborting execution.");
3196 /* Set lttng run dir */
3197 ret
= chown(LTTNG_RUNDIR
, 0, gid
);
3199 ERR("Unable to set group on " LTTNG_RUNDIR
);
3203 /* lttng client socket path */
3204 ret
= chown(client_unix_sock_path
, 0, gid
);
3206 ERR("Unable to set group on %s", client_unix_sock_path
);
3210 /* kconsumerd error socket path */
3211 ret
= chown(kconsumerd_err_unix_sock_path
, 0, gid
);
3213 ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path
);
3217 DBG("All permissions are set");
3224 * Create the pipe used to wake up the kernel thread.
3226 static int create_kernel_poll_pipe(void)
3228 return pipe2(kernel_poll_pipe
, O_CLOEXEC
);
3232 * Create the application command pipe to wake thread_manage_apps.
3234 static int create_apps_cmd_pipe(void)
3236 return pipe2(apps_cmd_pipe
, O_CLOEXEC
);
3240 * Create the lttng run directory needed for all global sockets and pipe.
3242 static int create_lttng_rundir(void)
3246 ret
= mkdir(LTTNG_RUNDIR
, S_IRWXU
| S_IRWXG
);
3248 if (errno
!= EEXIST
) {
3249 ERR("Unable to create " LTTNG_RUNDIR
);
3261 * Setup sockets and directory needed by the kconsumerd communication with the
3264 static int set_kconsumerd_sockets(void)
3268 if (strlen(kconsumerd_err_unix_sock_path
) == 0) {
3269 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
,
3270 KCONSUMERD_ERR_SOCK_PATH
);
3273 if (strlen(kconsumerd_cmd_unix_sock_path
) == 0) {
3274 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
,
3275 KCONSUMERD_CMD_SOCK_PATH
);
3278 ret
= mkdir(KCONSUMERD_PATH
, S_IRWXU
| S_IRWXG
);
3280 if (errno
!= EEXIST
) {
3281 ERR("Failed to create " KCONSUMERD_PATH
);
3287 /* Create the kconsumerd error unix socket */
3288 kconsumerd_err_sock
=
3289 lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path
);
3290 if (kconsumerd_err_sock
< 0) {
3291 ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path
);
3296 /* File permission MUST be 660 */
3297 ret
= chmod(kconsumerd_err_unix_sock_path
,
3298 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3300 ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path
);
3310 * Signal handler for the daemon
3312 * Simply stop all worker threads, leaving main() return gracefully after
3313 * joining all threads and calling cleanup().
3315 static void sighandler(int sig
)
3319 DBG("SIGPIPE catched");
3322 DBG("SIGINT catched");
3326 DBG("SIGTERM catched");
3335 * Setup signal handler for :
3336 * SIGINT, SIGTERM, SIGPIPE
3338 static int set_signal_handler(void)
3341 struct sigaction sa
;
3344 if ((ret
= sigemptyset(&sigset
)) < 0) {
3345 perror("sigemptyset");
3349 sa
.sa_handler
= sighandler
;
3350 sa
.sa_mask
= sigset
;
3352 if ((ret
= sigaction(SIGTERM
, &sa
, NULL
)) < 0) {
3353 perror("sigaction");
3357 if ((ret
= sigaction(SIGINT
, &sa
, NULL
)) < 0) {
3358 perror("sigaction");
3362 if ((ret
= sigaction(SIGPIPE
, &sa
, NULL
)) < 0) {
3363 perror("sigaction");
3367 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3373 * Set open files limit to unlimited. This daemon can open a large number of
3374 * file descriptors in order to consumer multiple kernel traces.
3376 static void set_ulimit(void)
3381 /* The kernel does not allowed an infinite limit for open files */
3382 lim
.rlim_cur
= 65535;
3383 lim
.rlim_max
= 65535;
3385 ret
= setrlimit(RLIMIT_NOFILE
, &lim
);
3387 perror("failed to set open files limit");
3394 int main(int argc
, char **argv
)
3398 const char *home_path
;
3400 /* Create thread quit pipe */
3401 if ((ret
= init_thread_quit_pipe()) < 0) {
3405 /* Parse arguments */
3407 if ((ret
= parse_args(argc
, argv
) < 0)) {
3420 /* Check if daemon is UID = 0 */
3421 is_root
= !getuid();
3424 ret
= create_lttng_rundir();
3429 if (strlen(apps_unix_sock_path
) == 0) {
3430 snprintf(apps_unix_sock_path
, PATH_MAX
,
3431 DEFAULT_GLOBAL_APPS_UNIX_SOCK
);
3434 if (strlen(client_unix_sock_path
) == 0) {
3435 snprintf(client_unix_sock_path
, PATH_MAX
,
3436 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
);
3439 /* Set global SHM for ust */
3440 if (strlen(wait_shm_path
) == 0) {
3441 snprintf(wait_shm_path
, PATH_MAX
,
3442 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH
);
3445 home_path
= get_home_dir();
3446 if (home_path
== NULL
) {
3447 /* TODO: Add --socket PATH option */
3448 ERR("Can't get HOME directory for sockets creation.");
3453 if (strlen(apps_unix_sock_path
) == 0) {
3454 snprintf(apps_unix_sock_path
, PATH_MAX
,
3455 DEFAULT_HOME_APPS_UNIX_SOCK
, home_path
);
3458 /* Set the cli tool unix socket path */
3459 if (strlen(client_unix_sock_path
) == 0) {
3460 snprintf(client_unix_sock_path
, PATH_MAX
,
3461 DEFAULT_HOME_CLIENT_UNIX_SOCK
, home_path
);
3464 /* Set global SHM for ust */
3465 if (strlen(wait_shm_path
) == 0) {
3466 snprintf(wait_shm_path
, PATH_MAX
,
3467 DEFAULT_HOME_APPS_WAIT_SHM_PATH
, geteuid());
3471 DBG("Client socket path %s", client_unix_sock_path
);
3472 DBG("Application socket path %s", apps_unix_sock_path
);
3475 * See if daemon already exist.
3477 if ((ret
= check_existing_daemon()) < 0) {
3478 ERR("Already running daemon.\n");
3480 * We do not goto exit because we must not cleanup()
3481 * because a daemon is already running.
3486 /* After this point, we can safely call cleanup() with "goto exit" */
3489 * These actions must be executed as root. We do that *after* setting up
3490 * the sockets path because we MUST make the check for another daemon using
3491 * those paths *before* trying to set the kernel consumer sockets and init
3495 ret
= set_kconsumerd_sockets();
3500 /* Setup kernel tracer */
3501 init_kernel_tracer();
3503 /* Set ulimit for open files */
3507 if ((ret
= set_signal_handler()) < 0) {
3511 /* Setup the needed unix socket */
3512 if ((ret
= init_daemon_socket()) < 0) {
3516 /* Set credentials to socket */
3517 if (is_root
&& ((ret
= set_permissions()) < 0)) {
3521 /* Get parent pid if -S, --sig-parent is specified. */
3522 if (opt_sig_parent
) {
3526 /* Setup the kernel pipe for waking up the kernel thread */
3527 if ((ret
= create_kernel_poll_pipe()) < 0) {
3531 /* Setup the thread apps communication pipe. */
3532 if ((ret
= create_apps_cmd_pipe()) < 0) {
3536 /* Init UST command queue. */
3537 cds_wfq_init(&ust_cmd_queue
.queue
);
3540 * Get session list pointer. This pointer MUST NOT be free(). This list is
3541 * statically declared in session.c
3543 session_list_ptr
= session_get_list();
3545 /* Set up max poll set size */
3546 lttng_poll_set_max_size();
3548 /* Create thread to manage the client socket */
3549 ret
= pthread_create(&client_thread
, NULL
,
3550 thread_manage_clients
, (void *) NULL
);
3552 perror("pthread_create clients");
3556 /* Create thread to dispatch registration */
3557 ret
= pthread_create(&dispatch_thread
, NULL
,
3558 thread_dispatch_ust_registration
, (void *) NULL
);
3560 perror("pthread_create dispatch");
3564 /* Create thread to manage application registration. */
3565 ret
= pthread_create(®_apps_thread
, NULL
,
3566 thread_registration_apps
, (void *) NULL
);
3568 perror("pthread_create registration");
3572 /* Create thread to manage application socket */
3573 ret
= pthread_create(&apps_thread
, NULL
,
3574 thread_manage_apps
, (void *) NULL
);
3576 perror("pthread_create apps");
3580 /* Create kernel thread to manage kernel event */
3581 ret
= pthread_create(&kernel_thread
, NULL
,
3582 thread_manage_kernel
, (void *) NULL
);
3584 perror("pthread_create kernel");
3588 ret
= pthread_join(kernel_thread
, &status
);
3590 perror("pthread_join");
3591 goto error
; /* join error, exit without cleanup */
3595 ret
= pthread_join(apps_thread
, &status
);
3597 perror("pthread_join");
3598 goto error
; /* join error, exit without cleanup */
3602 ret
= pthread_join(reg_apps_thread
, &status
);
3604 perror("pthread_join");
3605 goto error
; /* join error, exit without cleanup */
3609 ret
= pthread_join(dispatch_thread
, &status
);
3611 perror("pthread_join");
3612 goto error
; /* join error, exit without cleanup */
3616 ret
= pthread_join(client_thread
, &status
);
3618 perror("pthread_join");
3619 goto error
; /* join error, exit without cleanup */
3622 ret
= join_kconsumerd_thread();
3624 perror("join_kconsumerd");
3625 goto error
; /* join error, exit without cleanup */
3631 * cleanup() is called when no other thread is running.